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 If REDUCE_ALIGNMENT_OK is true, it is OK to reduce alignment.
355 We do not round to stack_boundary here. */
358 assign_stack_local_1 (enum machine_mode mode
, HOST_WIDE_INT size
,
360 bool reduce_alignment_ok ATTRIBUTE_UNUSED
)
363 int bigend_correction
= 0;
364 unsigned int alignment
, alignment_in_bits
;
365 int frame_off
, frame_alignment
, frame_phase
;
369 alignment
= get_stack_local_alignment (NULL
, mode
);
370 alignment
/= BITS_PER_UNIT
;
372 else if (align
== -1)
374 alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
375 size
= CEIL_ROUND (size
, alignment
);
377 else if (align
== -2)
378 alignment
= 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
380 alignment
= align
/ BITS_PER_UNIT
;
382 alignment_in_bits
= alignment
* BITS_PER_UNIT
;
384 if (FRAME_GROWS_DOWNWARD
)
385 frame_offset
-= size
;
387 /* Ignore alignment if it exceeds MAX_SUPPORTED_STACK_ALIGNMENT. */
388 if (alignment_in_bits
> MAX_SUPPORTED_STACK_ALIGNMENT
)
390 alignment_in_bits
= MAX_SUPPORTED_STACK_ALIGNMENT
;
391 alignment
= alignment_in_bits
/ BITS_PER_UNIT
;
394 if (SUPPORTS_STACK_ALIGNMENT
)
396 if (crtl
->stack_alignment_estimated
< alignment_in_bits
)
398 if (!crtl
->stack_realign_processed
)
399 crtl
->stack_alignment_estimated
= alignment_in_bits
;
402 /* If stack is realigned and stack alignment value
403 hasn't been finalized, it is OK not to increase
404 stack_alignment_estimated. The bigger alignment
405 requirement is recorded in stack_alignment_needed
407 gcc_assert (!crtl
->stack_realign_finalized
);
408 if (!crtl
->stack_realign_needed
)
410 /* It is OK to reduce the alignment as long as the
411 requested size is 0 or the estimated stack
412 alignment >= mode alignment. */
413 gcc_assert (reduce_alignment_ok
415 || (crtl
->stack_alignment_estimated
416 >= GET_MODE_ALIGNMENT (mode
)));
417 alignment_in_bits
= crtl
->stack_alignment_estimated
;
418 alignment
= alignment_in_bits
/ BITS_PER_UNIT
;
424 if (crtl
->stack_alignment_needed
< alignment_in_bits
)
425 crtl
->stack_alignment_needed
= alignment_in_bits
;
426 if (crtl
->max_used_stack_slot_alignment
< crtl
->stack_alignment_needed
)
427 crtl
->max_used_stack_slot_alignment
= crtl
->stack_alignment_needed
;
429 /* Calculate how many bytes the start of local variables is off from
431 frame_alignment
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
432 frame_off
= STARTING_FRAME_OFFSET
% frame_alignment
;
433 frame_phase
= frame_off
? frame_alignment
- frame_off
: 0;
435 /* Round the frame offset to the specified alignment. The default is
436 to always honor requests to align the stack but a port may choose to
437 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
438 if (STACK_ALIGNMENT_NEEDED
442 /* We must be careful here, since FRAME_OFFSET might be negative and
443 division with a negative dividend isn't as well defined as we might
444 like. So we instead assume that ALIGNMENT is a power of two and
445 use logical operations which are unambiguous. */
446 if (FRAME_GROWS_DOWNWARD
)
448 = (FLOOR_ROUND (frame_offset
- frame_phase
,
449 (unsigned HOST_WIDE_INT
) alignment
)
453 = (CEIL_ROUND (frame_offset
- frame_phase
,
454 (unsigned HOST_WIDE_INT
) alignment
)
458 /* On a big-endian machine, if we are allocating more space than we will use,
459 use the least significant bytes of those that are allocated. */
460 if (BYTES_BIG_ENDIAN
&& mode
!= BLKmode
&& GET_MODE_SIZE (mode
) < size
)
461 bigend_correction
= size
- GET_MODE_SIZE (mode
);
463 /* If we have already instantiated virtual registers, return the actual
464 address relative to the frame pointer. */
465 if (virtuals_instantiated
)
466 addr
= plus_constant (frame_pointer_rtx
,
468 (frame_offset
+ bigend_correction
469 + STARTING_FRAME_OFFSET
, Pmode
));
471 addr
= plus_constant (virtual_stack_vars_rtx
,
473 (frame_offset
+ bigend_correction
,
476 if (!FRAME_GROWS_DOWNWARD
)
477 frame_offset
+= size
;
479 x
= gen_rtx_MEM (mode
, addr
);
480 set_mem_align (x
, alignment_in_bits
);
481 MEM_NOTRAP_P (x
) = 1;
484 = gen_rtx_EXPR_LIST (VOIDmode
, x
, stack_slot_list
);
486 if (frame_offset_overflow (frame_offset
, current_function_decl
))
492 /* Wrap up assign_stack_local_1 with last parameter as false. */
495 assign_stack_local (enum machine_mode mode
, HOST_WIDE_INT size
, int align
)
497 return assign_stack_local_1 (mode
, size
, align
, false);
500 /* Removes temporary slot TEMP from LIST. */
503 cut_slot_from_list (struct temp_slot
*temp
, struct temp_slot
**list
)
506 temp
->next
->prev
= temp
->prev
;
508 temp
->prev
->next
= temp
->next
;
512 temp
->prev
= temp
->next
= NULL
;
515 /* Inserts temporary slot TEMP to LIST. */
518 insert_slot_to_list (struct temp_slot
*temp
, struct temp_slot
**list
)
522 (*list
)->prev
= temp
;
527 /* Returns the list of used temp slots at LEVEL. */
529 static struct temp_slot
**
530 temp_slots_at_level (int level
)
532 if (level
>= (int) VEC_length (temp_slot_p
, used_temp_slots
))
533 VEC_safe_grow_cleared (temp_slot_p
, gc
, used_temp_slots
, level
+ 1);
535 return &(VEC_address (temp_slot_p
, used_temp_slots
)[level
]);
538 /* Returns the maximal temporary slot level. */
541 max_slot_level (void)
543 if (!used_temp_slots
)
546 return VEC_length (temp_slot_p
, used_temp_slots
) - 1;
549 /* Moves temporary slot TEMP to LEVEL. */
552 move_slot_to_level (struct temp_slot
*temp
, int level
)
554 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
555 insert_slot_to_list (temp
, temp_slots_at_level (level
));
559 /* Make temporary slot TEMP available. */
562 make_slot_available (struct temp_slot
*temp
)
564 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
565 insert_slot_to_list (temp
, &avail_temp_slots
);
570 /* Allocate a temporary stack slot and record it for possible later
573 MODE is the machine mode to be given to the returned rtx.
575 SIZE is the size in units of the space required. We do no rounding here
576 since assign_stack_local will do any required rounding.
578 KEEP is 1 if this slot is to be retained after a call to
579 free_temp_slots. Automatic variables for a block are allocated
580 with this flag. KEEP values of 2 or 3 were needed respectively
581 for variables whose lifetime is controlled by CLEANUP_POINT_EXPRs
582 or for SAVE_EXPRs, but they are now unused.
584 TYPE is the type that will be used for the stack slot. */
587 assign_stack_temp_for_type (enum machine_mode mode
, HOST_WIDE_INT size
,
591 struct temp_slot
*p
, *best_p
= 0, *selected
= NULL
, **pp
;
594 /* If SIZE is -1 it means that somebody tried to allocate a temporary
595 of a variable size. */
596 gcc_assert (size
!= -1);
598 /* These are now unused. */
599 gcc_assert (keep
<= 1);
601 align
= get_stack_local_alignment (type
, mode
);
603 /* Try to find an available, already-allocated temporary of the proper
604 mode which meets the size and alignment requirements. Choose the
605 smallest one with the closest alignment.
607 If assign_stack_temp is called outside of the tree->rtl expansion,
608 we cannot reuse the stack slots (that may still refer to
609 VIRTUAL_STACK_VARS_REGNUM). */
610 if (!virtuals_instantiated
)
612 for (p
= avail_temp_slots
; p
; p
= p
->next
)
614 if (p
->align
>= align
&& p
->size
>= size
615 && GET_MODE (p
->slot
) == mode
616 && objects_must_conflict_p (p
->type
, type
)
617 && (best_p
== 0 || best_p
->size
> p
->size
618 || (best_p
->size
== p
->size
&& best_p
->align
> p
->align
)))
620 if (p
->align
== align
&& p
->size
== size
)
623 cut_slot_from_list (selected
, &avail_temp_slots
);
632 /* Make our best, if any, the one to use. */
636 cut_slot_from_list (selected
, &avail_temp_slots
);
638 /* If there are enough aligned bytes left over, make them into a new
639 temp_slot so that the extra bytes don't get wasted. Do this only
640 for BLKmode slots, so that we can be sure of the alignment. */
641 if (GET_MODE (best_p
->slot
) == BLKmode
)
643 int alignment
= best_p
->align
/ BITS_PER_UNIT
;
644 HOST_WIDE_INT rounded_size
= CEIL_ROUND (size
, alignment
);
646 if (best_p
->size
- rounded_size
>= alignment
)
648 p
= GGC_NEW (struct temp_slot
);
649 p
->in_use
= p
->addr_taken
= 0;
650 p
->size
= best_p
->size
- rounded_size
;
651 p
->base_offset
= best_p
->base_offset
+ rounded_size
;
652 p
->full_size
= best_p
->full_size
- rounded_size
;
653 p
->slot
= adjust_address_nv (best_p
->slot
, BLKmode
, rounded_size
);
654 p
->align
= best_p
->align
;
656 p
->type
= best_p
->type
;
657 insert_slot_to_list (p
, &avail_temp_slots
);
659 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, p
->slot
,
662 best_p
->size
= rounded_size
;
663 best_p
->full_size
= rounded_size
;
668 /* If we still didn't find one, make a new temporary. */
671 HOST_WIDE_INT frame_offset_old
= frame_offset
;
673 p
= GGC_NEW (struct temp_slot
);
675 /* We are passing an explicit alignment request to assign_stack_local.
676 One side effect of that is assign_stack_local will not round SIZE
677 to ensure the frame offset remains suitably aligned.
679 So for requests which depended on the rounding of SIZE, we go ahead
680 and round it now. We also make sure ALIGNMENT is at least
681 BIGGEST_ALIGNMENT. */
682 gcc_assert (mode
!= BLKmode
|| align
== BIGGEST_ALIGNMENT
);
683 p
->slot
= assign_stack_local (mode
,
685 ? CEIL_ROUND (size
, (int) align
/ BITS_PER_UNIT
)
691 /* The following slot size computation is necessary because we don't
692 know the actual size of the temporary slot until assign_stack_local
693 has performed all the frame alignment and size rounding for the
694 requested temporary. Note that extra space added for alignment
695 can be either above or below this stack slot depending on which
696 way the frame grows. We include the extra space if and only if it
697 is above this slot. */
698 if (FRAME_GROWS_DOWNWARD
)
699 p
->size
= frame_offset_old
- frame_offset
;
703 /* Now define the fields used by combine_temp_slots. */
704 if (FRAME_GROWS_DOWNWARD
)
706 p
->base_offset
= frame_offset
;
707 p
->full_size
= frame_offset_old
- frame_offset
;
711 p
->base_offset
= frame_offset_old
;
712 p
->full_size
= frame_offset
- frame_offset_old
;
723 p
->level
= temp_slot_level
;
726 pp
= temp_slots_at_level (p
->level
);
727 insert_slot_to_list (p
, pp
);
729 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
730 slot
= gen_rtx_MEM (mode
, XEXP (p
->slot
, 0));
731 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, slot
, stack_slot_list
);
733 /* If we know the alias set for the memory that will be used, use
734 it. If there's no TYPE, then we don't know anything about the
735 alias set for the memory. */
736 set_mem_alias_set (slot
, type
? get_alias_set (type
) : 0);
737 set_mem_align (slot
, align
);
739 /* If a type is specified, set the relevant flags. */
742 MEM_VOLATILE_P (slot
) = TYPE_VOLATILE (type
);
743 MEM_SET_IN_STRUCT_P (slot
, (AGGREGATE_TYPE_P (type
)
744 || TREE_CODE (type
) == COMPLEX_TYPE
));
746 MEM_NOTRAP_P (slot
) = 1;
751 /* Allocate a temporary stack slot and record it for possible later
752 reuse. First three arguments are same as in preceding function. */
755 assign_stack_temp (enum machine_mode mode
, HOST_WIDE_INT size
, int keep
)
757 return assign_stack_temp_for_type (mode
, size
, keep
, NULL_TREE
);
760 /* Assign a temporary.
761 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
762 and so that should be used in error messages. In either case, we
763 allocate of the given type.
764 KEEP is as for assign_stack_temp.
765 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
766 it is 0 if a register is OK.
767 DONT_PROMOTE is 1 if we should not promote values in register
771 assign_temp (tree type_or_decl
, int keep
, int memory_required
,
772 int dont_promote ATTRIBUTE_UNUSED
)
775 enum machine_mode mode
;
780 if (DECL_P (type_or_decl
))
781 decl
= type_or_decl
, type
= TREE_TYPE (decl
);
783 decl
= NULL
, type
= type_or_decl
;
785 mode
= TYPE_MODE (type
);
787 unsignedp
= TYPE_UNSIGNED (type
);
790 if (mode
== BLKmode
|| memory_required
)
792 HOST_WIDE_INT size
= int_size_in_bytes (type
);
795 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
796 problems with allocating the stack space. */
800 /* Unfortunately, we don't yet know how to allocate variable-sized
801 temporaries. However, sometimes we can find a fixed upper limit on
802 the size, so try that instead. */
804 size
= max_int_size_in_bytes (type
);
806 /* The size of the temporary may be too large to fit into an integer. */
807 /* ??? Not sure this should happen except for user silliness, so limit
808 this to things that aren't compiler-generated temporaries. The
809 rest of the time we'll die in assign_stack_temp_for_type. */
810 if (decl
&& size
== -1
811 && TREE_CODE (TYPE_SIZE_UNIT (type
)) == INTEGER_CST
)
813 error ("size of variable %q+D is too large", decl
);
817 tmp
= assign_stack_temp_for_type (mode
, size
, keep
, type
);
823 mode
= promote_mode (type
, mode
, &unsignedp
, 0);
826 return gen_reg_rtx (mode
);
829 /* Combine temporary stack slots which are adjacent on the stack.
831 This allows for better use of already allocated stack space. This is only
832 done for BLKmode slots because we can be sure that we won't have alignment
833 problems in this case. */
836 combine_temp_slots (void)
838 struct temp_slot
*p
, *q
, *next
, *next_q
;
841 /* We can't combine slots, because the information about which slot
842 is in which alias set will be lost. */
843 if (flag_strict_aliasing
)
846 /* If there are a lot of temp slots, don't do anything unless
847 high levels of optimization. */
848 if (! flag_expensive_optimizations
)
849 for (p
= avail_temp_slots
, num_slots
= 0; p
; p
= p
->next
, num_slots
++)
850 if (num_slots
> 100 || (num_slots
> 10 && optimize
== 0))
853 for (p
= avail_temp_slots
; p
; p
= next
)
859 if (GET_MODE (p
->slot
) != BLKmode
)
862 for (q
= p
->next
; q
; q
= next_q
)
868 if (GET_MODE (q
->slot
) != BLKmode
)
871 if (p
->base_offset
+ p
->full_size
== q
->base_offset
)
873 /* Q comes after P; combine Q into P. */
875 p
->full_size
+= q
->full_size
;
878 else if (q
->base_offset
+ q
->full_size
== p
->base_offset
)
880 /* P comes after Q; combine P into Q. */
882 q
->full_size
+= p
->full_size
;
887 cut_slot_from_list (q
, &avail_temp_slots
);
890 /* Either delete P or advance past it. */
892 cut_slot_from_list (p
, &avail_temp_slots
);
896 /* Find the temp slot corresponding to the object at address X. */
898 static struct temp_slot
*
899 find_temp_slot_from_address (rtx x
)
905 for (i
= max_slot_level (); i
>= 0; i
--)
906 for (p
= *temp_slots_at_level (i
); p
; p
= p
->next
)
908 if (XEXP (p
->slot
, 0) == x
910 || (GET_CODE (x
) == PLUS
911 && XEXP (x
, 0) == virtual_stack_vars_rtx
912 && GET_CODE (XEXP (x
, 1)) == CONST_INT
913 && INTVAL (XEXP (x
, 1)) >= p
->base_offset
914 && INTVAL (XEXP (x
, 1)) < p
->base_offset
+ p
->full_size
))
917 else if (p
->address
!= 0 && GET_CODE (p
->address
) == EXPR_LIST
)
918 for (next
= p
->address
; next
; next
= XEXP (next
, 1))
919 if (XEXP (next
, 0) == x
)
923 /* If we have a sum involving a register, see if it points to a temp
925 if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 0))
926 && (p
= find_temp_slot_from_address (XEXP (x
, 0))) != 0)
928 else if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 1))
929 && (p
= find_temp_slot_from_address (XEXP (x
, 1))) != 0)
935 /* Indicate that NEW_RTX is an alternate way of referring to the temp
936 slot that previously was known by OLD_RTX. */
939 update_temp_slot_address (rtx old_rtx
, rtx new_rtx
)
943 if (rtx_equal_p (old_rtx
, new_rtx
))
946 p
= find_temp_slot_from_address (old_rtx
);
948 /* If we didn't find one, see if both OLD_RTX is a PLUS. If so, and
949 NEW_RTX is a register, see if one operand of the PLUS is a
950 temporary location. If so, NEW_RTX points into it. Otherwise,
951 if both OLD_RTX and NEW_RTX are a PLUS and if there is a register
952 in common between them. If so, try a recursive call on those
956 if (GET_CODE (old_rtx
) != PLUS
)
961 update_temp_slot_address (XEXP (old_rtx
, 0), new_rtx
);
962 update_temp_slot_address (XEXP (old_rtx
, 1), new_rtx
);
965 else if (GET_CODE (new_rtx
) != PLUS
)
968 if (rtx_equal_p (XEXP (old_rtx
, 0), XEXP (new_rtx
, 0)))
969 update_temp_slot_address (XEXP (old_rtx
, 1), XEXP (new_rtx
, 1));
970 else if (rtx_equal_p (XEXP (old_rtx
, 1), XEXP (new_rtx
, 0)))
971 update_temp_slot_address (XEXP (old_rtx
, 0), XEXP (new_rtx
, 1));
972 else if (rtx_equal_p (XEXP (old_rtx
, 0), XEXP (new_rtx
, 1)))
973 update_temp_slot_address (XEXP (old_rtx
, 1), XEXP (new_rtx
, 0));
974 else if (rtx_equal_p (XEXP (old_rtx
, 1), XEXP (new_rtx
, 1)))
975 update_temp_slot_address (XEXP (old_rtx
, 0), XEXP (new_rtx
, 0));
980 /* Otherwise add an alias for the temp's address. */
981 else if (p
->address
== 0)
982 p
->address
= new_rtx
;
985 if (GET_CODE (p
->address
) != EXPR_LIST
)
986 p
->address
= gen_rtx_EXPR_LIST (VOIDmode
, p
->address
, NULL_RTX
);
988 p
->address
= gen_rtx_EXPR_LIST (VOIDmode
, new_rtx
, p
->address
);
992 /* If X could be a reference to a temporary slot, mark the fact that its
993 address was taken. */
996 mark_temp_addr_taken (rtx x
)
1003 /* If X is not in memory or is at a constant address, it cannot be in
1004 a temporary slot. */
1005 if (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0)))
1008 p
= find_temp_slot_from_address (XEXP (x
, 0));
1013 /* If X could be a reference to a temporary slot, mark that slot as
1014 belonging to the to one level higher than the current level. If X
1015 matched one of our slots, just mark that one. Otherwise, we can't
1016 easily predict which it is, so upgrade all of them. Kept slots
1017 need not be touched.
1019 This is called when an ({...}) construct occurs and a statement
1020 returns a value in memory. */
1023 preserve_temp_slots (rtx x
)
1025 struct temp_slot
*p
= 0, *next
;
1027 /* If there is no result, we still might have some objects whose address
1028 were taken, so we need to make sure they stay around. */
1031 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1036 move_slot_to_level (p
, temp_slot_level
- 1);
1042 /* If X is a register that is being used as a pointer, see if we have
1043 a temporary slot we know it points to. To be consistent with
1044 the code below, we really should preserve all non-kept slots
1045 if we can't find a match, but that seems to be much too costly. */
1046 if (REG_P (x
) && REG_POINTER (x
))
1047 p
= find_temp_slot_from_address (x
);
1049 /* If X is not in memory or is at a constant address, it cannot be in
1050 a temporary slot, but it can contain something whose address was
1052 if (p
== 0 && (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0))))
1054 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1059 move_slot_to_level (p
, temp_slot_level
- 1);
1065 /* First see if we can find a match. */
1067 p
= find_temp_slot_from_address (XEXP (x
, 0));
1071 /* Move everything at our level whose address was taken to our new
1072 level in case we used its address. */
1073 struct temp_slot
*q
;
1075 if (p
->level
== temp_slot_level
)
1077 for (q
= *temp_slots_at_level (temp_slot_level
); q
; q
= next
)
1081 if (p
!= q
&& q
->addr_taken
)
1082 move_slot_to_level (q
, temp_slot_level
- 1);
1085 move_slot_to_level (p
, temp_slot_level
- 1);
1091 /* Otherwise, preserve all non-kept slots at this level. */
1092 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1097 move_slot_to_level (p
, temp_slot_level
- 1);
1101 /* Free all temporaries used so far. This is normally called at the
1102 end of generating code for a statement. */
1105 free_temp_slots (void)
1107 struct temp_slot
*p
, *next
;
1109 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1114 make_slot_available (p
);
1117 combine_temp_slots ();
1120 /* Push deeper into the nesting level for stack temporaries. */
1123 push_temp_slots (void)
1128 /* Pop a temporary nesting level. All slots in use in the current level
1132 pop_temp_slots (void)
1134 struct temp_slot
*p
, *next
;
1136 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1139 make_slot_available (p
);
1142 combine_temp_slots ();
1147 /* Initialize temporary slots. */
1150 init_temp_slots (void)
1152 /* We have not allocated any temporaries yet. */
1153 avail_temp_slots
= 0;
1154 used_temp_slots
= 0;
1155 temp_slot_level
= 0;
1158 /* These routines are responsible for converting virtual register references
1159 to the actual hard register references once RTL generation is complete.
1161 The following four variables are used for communication between the
1162 routines. They contain the offsets of the virtual registers from their
1163 respective hard registers. */
1165 static int in_arg_offset
;
1166 static int var_offset
;
1167 static int dynamic_offset
;
1168 static int out_arg_offset
;
1169 static int cfa_offset
;
1171 /* In most machines, the stack pointer register is equivalent to the bottom
1174 #ifndef STACK_POINTER_OFFSET
1175 #define STACK_POINTER_OFFSET 0
1178 /* If not defined, pick an appropriate default for the offset of dynamically
1179 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1180 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1182 #ifndef STACK_DYNAMIC_OFFSET
1184 /* The bottom of the stack points to the actual arguments. If
1185 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1186 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1187 stack space for register parameters is not pushed by the caller, but
1188 rather part of the fixed stack areas and hence not included in
1189 `crtl->outgoing_args_size'. Nevertheless, we must allow
1190 for it when allocating stack dynamic objects. */
1192 #if defined(REG_PARM_STACK_SPACE)
1193 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1194 ((ACCUMULATE_OUTGOING_ARGS \
1195 ? (crtl->outgoing_args_size \
1196 + (OUTGOING_REG_PARM_STACK_SPACE ((!(FNDECL) ? NULL_TREE : TREE_TYPE (FNDECL))) ? 0 \
1197 : REG_PARM_STACK_SPACE (FNDECL))) \
1198 : 0) + (STACK_POINTER_OFFSET))
1200 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1201 ((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : 0) \
1202 + (STACK_POINTER_OFFSET))
1207 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1208 is a virtual register, return the equivalent hard register and set the
1209 offset indirectly through the pointer. Otherwise, return 0. */
1212 instantiate_new_reg (rtx x
, HOST_WIDE_INT
*poffset
)
1215 HOST_WIDE_INT offset
;
1217 if (x
== virtual_incoming_args_rtx
)
1219 if (stack_realign_drap
)
1221 /* Replace virtual_incoming_args_rtx with internal arg
1222 pointer if DRAP is used to realign stack. */
1223 new_rtx
= crtl
->args
.internal_arg_pointer
;
1227 new_rtx
= arg_pointer_rtx
, offset
= in_arg_offset
;
1229 else if (x
== virtual_stack_vars_rtx
)
1230 new_rtx
= frame_pointer_rtx
, offset
= var_offset
;
1231 else if (x
== virtual_stack_dynamic_rtx
)
1232 new_rtx
= stack_pointer_rtx
, offset
= dynamic_offset
;
1233 else if (x
== virtual_outgoing_args_rtx
)
1234 new_rtx
= stack_pointer_rtx
, offset
= out_arg_offset
;
1235 else if (x
== virtual_cfa_rtx
)
1237 #ifdef FRAME_POINTER_CFA_OFFSET
1238 new_rtx
= frame_pointer_rtx
;
1240 new_rtx
= arg_pointer_rtx
;
1242 offset
= cfa_offset
;
1251 /* A subroutine of instantiate_virtual_regs, called via for_each_rtx.
1252 Instantiate any virtual registers present inside of *LOC. The expression
1253 is simplified, as much as possible, but is not to be considered "valid"
1254 in any sense implied by the target. If any change is made, set CHANGED
1258 instantiate_virtual_regs_in_rtx (rtx
*loc
, void *data
)
1260 HOST_WIDE_INT offset
;
1261 bool *changed
= (bool *) data
;
1268 switch (GET_CODE (x
))
1271 new_rtx
= instantiate_new_reg (x
, &offset
);
1274 *loc
= plus_constant (new_rtx
, offset
);
1281 new_rtx
= instantiate_new_reg (XEXP (x
, 0), &offset
);
1284 new_rtx
= plus_constant (new_rtx
, offset
);
1285 *loc
= simplify_gen_binary (PLUS
, GET_MODE (x
), new_rtx
, XEXP (x
, 1));
1291 /* FIXME -- from old code */
1292 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1293 we can commute the PLUS and SUBREG because pointers into the
1294 frame are well-behaved. */
1304 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1305 matches the predicate for insn CODE operand OPERAND. */
1308 safe_insn_predicate (int code
, int operand
, rtx x
)
1310 const struct insn_operand_data
*op_data
;
1315 op_data
= &insn_data
[code
].operand
[operand
];
1316 if (op_data
->predicate
== NULL
)
1319 return op_data
->predicate (x
, op_data
->mode
);
1322 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1323 registers present inside of insn. The result will be a valid insn. */
1326 instantiate_virtual_regs_in_insn (rtx insn
)
1328 HOST_WIDE_INT offset
;
1330 bool any_change
= false;
1331 rtx set
, new_rtx
, x
, seq
;
1333 /* There are some special cases to be handled first. */
1334 set
= single_set (insn
);
1337 /* We're allowed to assign to a virtual register. This is interpreted
1338 to mean that the underlying register gets assigned the inverse
1339 transformation. This is used, for example, in the handling of
1341 new_rtx
= instantiate_new_reg (SET_DEST (set
), &offset
);
1346 for_each_rtx (&SET_SRC (set
), instantiate_virtual_regs_in_rtx
, NULL
);
1347 x
= simplify_gen_binary (PLUS
, GET_MODE (new_rtx
), SET_SRC (set
),
1349 x
= force_operand (x
, new_rtx
);
1351 emit_move_insn (new_rtx
, x
);
1356 emit_insn_before (seq
, insn
);
1361 /* Handle a straight copy from a virtual register by generating a
1362 new add insn. The difference between this and falling through
1363 to the generic case is avoiding a new pseudo and eliminating a
1364 move insn in the initial rtl stream. */
1365 new_rtx
= instantiate_new_reg (SET_SRC (set
), &offset
);
1366 if (new_rtx
&& offset
!= 0
1367 && REG_P (SET_DEST (set
))
1368 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1372 x
= expand_simple_binop (GET_MODE (SET_DEST (set
)), PLUS
,
1373 new_rtx
, GEN_INT (offset
), SET_DEST (set
),
1374 1, OPTAB_LIB_WIDEN
);
1375 if (x
!= SET_DEST (set
))
1376 emit_move_insn (SET_DEST (set
), x
);
1381 emit_insn_before (seq
, insn
);
1386 extract_insn (insn
);
1387 insn_code
= INSN_CODE (insn
);
1389 /* Handle a plus involving a virtual register by determining if the
1390 operands remain valid if they're modified in place. */
1391 if (GET_CODE (SET_SRC (set
)) == PLUS
1392 && recog_data
.n_operands
>= 3
1393 && recog_data
.operand_loc
[1] == &XEXP (SET_SRC (set
), 0)
1394 && recog_data
.operand_loc
[2] == &XEXP (SET_SRC (set
), 1)
1395 && GET_CODE (recog_data
.operand
[2]) == CONST_INT
1396 && (new_rtx
= instantiate_new_reg (recog_data
.operand
[1], &offset
)))
1398 offset
+= INTVAL (recog_data
.operand
[2]);
1400 /* If the sum is zero, then replace with a plain move. */
1402 && REG_P (SET_DEST (set
))
1403 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1406 emit_move_insn (SET_DEST (set
), new_rtx
);
1410 emit_insn_before (seq
, insn
);
1415 x
= gen_int_mode (offset
, recog_data
.operand_mode
[2]);
1417 /* Using validate_change and apply_change_group here leaves
1418 recog_data in an invalid state. Since we know exactly what
1419 we want to check, do those two by hand. */
1420 if (safe_insn_predicate (insn_code
, 1, new_rtx
)
1421 && safe_insn_predicate (insn_code
, 2, x
))
1423 *recog_data
.operand_loc
[1] = recog_data
.operand
[1] = new_rtx
;
1424 *recog_data
.operand_loc
[2] = recog_data
.operand
[2] = x
;
1427 /* Fall through into the regular operand fixup loop in
1428 order to take care of operands other than 1 and 2. */
1434 extract_insn (insn
);
1435 insn_code
= INSN_CODE (insn
);
1438 /* In the general case, we expect virtual registers to appear only in
1439 operands, and then only as either bare registers or inside memories. */
1440 for (i
= 0; i
< recog_data
.n_operands
; ++i
)
1442 x
= recog_data
.operand
[i
];
1443 switch (GET_CODE (x
))
1447 rtx addr
= XEXP (x
, 0);
1448 bool changed
= false;
1450 for_each_rtx (&addr
, instantiate_virtual_regs_in_rtx
, &changed
);
1455 x
= replace_equiv_address (x
, addr
);
1456 /* It may happen that the address with the virtual reg
1457 was valid (e.g. based on the virtual stack reg, which might
1458 be acceptable to the predicates with all offsets), whereas
1459 the address now isn't anymore, for instance when the address
1460 is still offsetted, but the base reg isn't virtual-stack-reg
1461 anymore. Below we would do a force_reg on the whole operand,
1462 but this insn might actually only accept memory. Hence,
1463 before doing that last resort, try to reload the address into
1464 a register, so this operand stays a MEM. */
1465 if (!safe_insn_predicate (insn_code
, i
, x
))
1467 addr
= force_reg (GET_MODE (addr
), addr
);
1468 x
= replace_equiv_address (x
, addr
);
1473 emit_insn_before (seq
, insn
);
1478 new_rtx
= instantiate_new_reg (x
, &offset
);
1479 if (new_rtx
== NULL
)
1487 /* Careful, special mode predicates may have stuff in
1488 insn_data[insn_code].operand[i].mode that isn't useful
1489 to us for computing a new value. */
1490 /* ??? Recognize address_operand and/or "p" constraints
1491 to see if (plus new offset) is a valid before we put
1492 this through expand_simple_binop. */
1493 x
= expand_simple_binop (GET_MODE (x
), PLUS
, new_rtx
,
1494 GEN_INT (offset
), NULL_RTX
,
1495 1, OPTAB_LIB_WIDEN
);
1498 emit_insn_before (seq
, insn
);
1503 new_rtx
= instantiate_new_reg (SUBREG_REG (x
), &offset
);
1504 if (new_rtx
== NULL
)
1509 new_rtx
= expand_simple_binop (GET_MODE (new_rtx
), PLUS
, new_rtx
,
1510 GEN_INT (offset
), NULL_RTX
,
1511 1, OPTAB_LIB_WIDEN
);
1514 emit_insn_before (seq
, insn
);
1516 x
= simplify_gen_subreg (recog_data
.operand_mode
[i
], new_rtx
,
1517 GET_MODE (new_rtx
), SUBREG_BYTE (x
));
1524 /* At this point, X contains the new value for the operand.
1525 Validate the new value vs the insn predicate. Note that
1526 asm insns will have insn_code -1 here. */
1527 if (!safe_insn_predicate (insn_code
, i
, x
))
1530 x
= force_reg (insn_data
[insn_code
].operand
[i
].mode
, x
);
1534 emit_insn_before (seq
, insn
);
1537 *recog_data
.operand_loc
[i
] = recog_data
.operand
[i
] = x
;
1543 /* Propagate operand changes into the duplicates. */
1544 for (i
= 0; i
< recog_data
.n_dups
; ++i
)
1545 *recog_data
.dup_loc
[i
]
1546 = copy_rtx (recog_data
.operand
[(unsigned)recog_data
.dup_num
[i
]]);
1548 /* Force re-recognition of the instruction for validation. */
1549 INSN_CODE (insn
) = -1;
1552 if (asm_noperands (PATTERN (insn
)) >= 0)
1554 if (!check_asm_operands (PATTERN (insn
)))
1556 error_for_asm (insn
, "impossible constraint in %<asm%>");
1562 if (recog_memoized (insn
) < 0)
1563 fatal_insn_not_found (insn
);
1567 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1568 do any instantiation required. */
1571 instantiate_decl_rtl (rtx x
)
1578 /* If this is a CONCAT, recurse for the pieces. */
1579 if (GET_CODE (x
) == CONCAT
)
1581 instantiate_decl_rtl (XEXP (x
, 0));
1582 instantiate_decl_rtl (XEXP (x
, 1));
1586 /* If this is not a MEM, no need to do anything. Similarly if the
1587 address is a constant or a register that is not a virtual register. */
1592 if (CONSTANT_P (addr
)
1594 && (REGNO (addr
) < FIRST_VIRTUAL_REGISTER
1595 || REGNO (addr
) > LAST_VIRTUAL_REGISTER
)))
1598 for_each_rtx (&XEXP (x
, 0), instantiate_virtual_regs_in_rtx
, NULL
);
1601 /* Helper for instantiate_decls called via walk_tree: Process all decls
1602 in the given DECL_VALUE_EXPR. */
1605 instantiate_expr (tree
*tp
, int *walk_subtrees
, void *data ATTRIBUTE_UNUSED
)
1611 if (DECL_P (t
) && DECL_RTL_SET_P (t
))
1612 instantiate_decl_rtl (DECL_RTL (t
));
1617 /* Subroutine of instantiate_decls: Process all decls in the given
1618 BLOCK node and all its subblocks. */
1621 instantiate_decls_1 (tree let
)
1625 for (t
= BLOCK_VARS (let
); t
; t
= TREE_CHAIN (t
))
1627 if (DECL_RTL_SET_P (t
))
1628 instantiate_decl_rtl (DECL_RTL (t
));
1629 if (TREE_CODE (t
) == VAR_DECL
&& DECL_HAS_VALUE_EXPR_P (t
))
1631 tree v
= DECL_VALUE_EXPR (t
);
1632 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1636 /* Process all subblocks. */
1637 for (t
= BLOCK_SUBBLOCKS (let
); t
; t
= BLOCK_CHAIN (t
))
1638 instantiate_decls_1 (t
);
1641 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1642 all virtual registers in their DECL_RTL's. */
1645 instantiate_decls (tree fndecl
)
1649 /* Process all parameters of the function. */
1650 for (decl
= DECL_ARGUMENTS (fndecl
); decl
; decl
= TREE_CHAIN (decl
))
1652 instantiate_decl_rtl (DECL_RTL (decl
));
1653 instantiate_decl_rtl (DECL_INCOMING_RTL (decl
));
1654 if (DECL_HAS_VALUE_EXPR_P (decl
))
1656 tree v
= DECL_VALUE_EXPR (decl
);
1657 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1661 /* Now process all variables defined in the function or its subblocks. */
1662 instantiate_decls_1 (DECL_INITIAL (fndecl
));
1665 /* Pass through the INSNS of function FNDECL and convert virtual register
1666 references to hard register references. */
1669 instantiate_virtual_regs (void)
1673 /* Compute the offsets to use for this function. */
1674 in_arg_offset
= FIRST_PARM_OFFSET (current_function_decl
);
1675 var_offset
= STARTING_FRAME_OFFSET
;
1676 dynamic_offset
= STACK_DYNAMIC_OFFSET (current_function_decl
);
1677 out_arg_offset
= STACK_POINTER_OFFSET
;
1678 #ifdef FRAME_POINTER_CFA_OFFSET
1679 cfa_offset
= FRAME_POINTER_CFA_OFFSET (current_function_decl
);
1681 cfa_offset
= ARG_POINTER_CFA_OFFSET (current_function_decl
);
1684 /* Initialize recognition, indicating that volatile is OK. */
1687 /* Scan through all the insns, instantiating every virtual register still
1689 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
1692 /* These patterns in the instruction stream can never be recognized.
1693 Fortunately, they shouldn't contain virtual registers either. */
1694 if (GET_CODE (PATTERN (insn
)) == USE
1695 || GET_CODE (PATTERN (insn
)) == CLOBBER
1696 || GET_CODE (PATTERN (insn
)) == ADDR_VEC
1697 || GET_CODE (PATTERN (insn
)) == ADDR_DIFF_VEC
1698 || GET_CODE (PATTERN (insn
)) == ASM_INPUT
)
1701 instantiate_virtual_regs_in_insn (insn
);
1703 if (INSN_DELETED_P (insn
))
1706 for_each_rtx (®_NOTES (insn
), instantiate_virtual_regs_in_rtx
, NULL
);
1708 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1709 if (GET_CODE (insn
) == CALL_INSN
)
1710 for_each_rtx (&CALL_INSN_FUNCTION_USAGE (insn
),
1711 instantiate_virtual_regs_in_rtx
, NULL
);
1714 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1715 instantiate_decls (current_function_decl
);
1717 targetm
.instantiate_decls ();
1719 /* Indicate that, from now on, assign_stack_local should use
1720 frame_pointer_rtx. */
1721 virtuals_instantiated
= 1;
1725 struct rtl_opt_pass pass_instantiate_virtual_regs
=
1731 instantiate_virtual_regs
, /* execute */
1734 0, /* static_pass_number */
1736 0, /* properties_required */
1737 0, /* properties_provided */
1738 0, /* properties_destroyed */
1739 0, /* todo_flags_start */
1740 TODO_dump_func
/* todo_flags_finish */
1745 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
1746 This means a type for which function calls must pass an address to the
1747 function or get an address back from the function.
1748 EXP may be a type node or an expression (whose type is tested). */
1751 aggregate_value_p (const_tree exp
, const_tree fntype
)
1753 int i
, regno
, nregs
;
1756 const_tree type
= (TYPE_P (exp
)) ? exp
: TREE_TYPE (exp
);
1758 /* DECL node associated with FNTYPE when relevant, which we might need to
1759 check for by-invisible-reference returns, typically for CALL_EXPR input
1761 const_tree fndecl
= NULL_TREE
;
1764 switch (TREE_CODE (fntype
))
1767 fndecl
= get_callee_fndecl (fntype
);
1768 fntype
= fndecl
? TREE_TYPE (fndecl
) : 0;
1772 fntype
= TREE_TYPE (fndecl
);
1777 case IDENTIFIER_NODE
:
1781 /* We don't expect other rtl types here. */
1785 if (TREE_CODE (type
) == VOID_TYPE
)
1788 /* If the front end has decided that this needs to be passed by
1789 reference, do so. */
1790 if ((TREE_CODE (exp
) == PARM_DECL
|| TREE_CODE (exp
) == RESULT_DECL
)
1791 && DECL_BY_REFERENCE (exp
))
1794 /* If the EXPression is a CALL_EXPR, honor DECL_BY_REFERENCE set on the
1795 called function RESULT_DECL, meaning the function returns in memory by
1796 invisible reference. This check lets front-ends not set TREE_ADDRESSABLE
1797 on the function type, which used to be the way to request such a return
1798 mechanism but might now be causing troubles at gimplification time if
1799 temporaries with the function type need to be created. */
1800 if (TREE_CODE (exp
) == CALL_EXPR
&& fndecl
&& DECL_RESULT (fndecl
)
1801 && DECL_BY_REFERENCE (DECL_RESULT (fndecl
)))
1804 if (targetm
.calls
.return_in_memory (type
, fntype
))
1806 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
1807 and thus can't be returned in registers. */
1808 if (TREE_ADDRESSABLE (type
))
1810 if (flag_pcc_struct_return
&& AGGREGATE_TYPE_P (type
))
1812 /* Make sure we have suitable call-clobbered regs to return
1813 the value in; if not, we must return it in memory. */
1814 reg
= hard_function_value (type
, 0, fntype
, 0);
1816 /* If we have something other than a REG (e.g. a PARALLEL), then assume
1821 regno
= REGNO (reg
);
1822 nregs
= hard_regno_nregs
[regno
][TYPE_MODE (type
)];
1823 for (i
= 0; i
< nregs
; i
++)
1824 if (! call_used_regs
[regno
+ i
])
1829 /* Return true if we should assign DECL a pseudo register; false if it
1830 should live on the local stack. */
1833 use_register_for_decl (const_tree decl
)
1835 if (!targetm
.calls
.allocate_stack_slots_for_args())
1838 /* Honor volatile. */
1839 if (TREE_SIDE_EFFECTS (decl
))
1842 /* Honor addressability. */
1843 if (TREE_ADDRESSABLE (decl
))
1846 /* Only register-like things go in registers. */
1847 if (DECL_MODE (decl
) == BLKmode
)
1850 /* If -ffloat-store specified, don't put explicit float variables
1852 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
1853 propagates values across these stores, and it probably shouldn't. */
1854 if (flag_float_store
&& FLOAT_TYPE_P (TREE_TYPE (decl
)))
1857 /* If we're not interested in tracking debugging information for
1858 this decl, then we can certainly put it in a register. */
1859 if (DECL_IGNORED_P (decl
))
1862 return (optimize
|| DECL_REGISTER (decl
));
1865 /* Return true if TYPE should be passed by invisible reference. */
1868 pass_by_reference (CUMULATIVE_ARGS
*ca
, enum machine_mode mode
,
1869 tree type
, bool named_arg
)
1873 /* If this type contains non-trivial constructors, then it is
1874 forbidden for the middle-end to create any new copies. */
1875 if (TREE_ADDRESSABLE (type
))
1878 /* GCC post 3.4 passes *all* variable sized types by reference. */
1879 if (!TYPE_SIZE (type
) || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
1883 return targetm
.calls
.pass_by_reference (ca
, mode
, type
, named_arg
);
1886 /* Return true if TYPE, which is passed by reference, should be callee
1887 copied instead of caller copied. */
1890 reference_callee_copied (CUMULATIVE_ARGS
*ca
, enum machine_mode mode
,
1891 tree type
, bool named_arg
)
1893 if (type
&& TREE_ADDRESSABLE (type
))
1895 return targetm
.calls
.callee_copies (ca
, mode
, type
, named_arg
);
1898 /* Structures to communicate between the subroutines of assign_parms.
1899 The first holds data persistent across all parameters, the second
1900 is cleared out for each parameter. */
1902 struct assign_parm_data_all
1904 CUMULATIVE_ARGS args_so_far
;
1905 struct args_size stack_args_size
;
1906 tree function_result_decl
;
1908 rtx first_conversion_insn
;
1909 rtx last_conversion_insn
;
1910 HOST_WIDE_INT pretend_args_size
;
1911 HOST_WIDE_INT extra_pretend_bytes
;
1912 int reg_parm_stack_space
;
1915 struct assign_parm_data_one
1921 enum machine_mode nominal_mode
;
1922 enum machine_mode passed_mode
;
1923 enum machine_mode promoted_mode
;
1924 struct locate_and_pad_arg_data locate
;
1926 BOOL_BITFIELD named_arg
: 1;
1927 BOOL_BITFIELD passed_pointer
: 1;
1928 BOOL_BITFIELD on_stack
: 1;
1929 BOOL_BITFIELD loaded_in_reg
: 1;
1932 /* A subroutine of assign_parms. Initialize ALL. */
1935 assign_parms_initialize_all (struct assign_parm_data_all
*all
)
1939 memset (all
, 0, sizeof (*all
));
1941 fntype
= TREE_TYPE (current_function_decl
);
1943 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
1944 INIT_CUMULATIVE_INCOMING_ARGS (all
->args_so_far
, fntype
, NULL_RTX
);
1946 INIT_CUMULATIVE_ARGS (all
->args_so_far
, fntype
, NULL_RTX
,
1947 current_function_decl
, -1);
1950 #ifdef REG_PARM_STACK_SPACE
1951 all
->reg_parm_stack_space
= REG_PARM_STACK_SPACE (current_function_decl
);
1955 /* If ARGS contains entries with complex types, split the entry into two
1956 entries of the component type. Return a new list of substitutions are
1957 needed, else the old list. */
1960 split_complex_args (tree args
)
1964 /* Before allocating memory, check for the common case of no complex. */
1965 for (p
= args
; p
; p
= TREE_CHAIN (p
))
1967 tree type
= TREE_TYPE (p
);
1968 if (TREE_CODE (type
) == COMPLEX_TYPE
1969 && targetm
.calls
.split_complex_arg (type
))
1975 args
= copy_list (args
);
1977 for (p
= args
; p
; p
= TREE_CHAIN (p
))
1979 tree type
= TREE_TYPE (p
);
1980 if (TREE_CODE (type
) == COMPLEX_TYPE
1981 && targetm
.calls
.split_complex_arg (type
))
1984 tree subtype
= TREE_TYPE (type
);
1985 bool addressable
= TREE_ADDRESSABLE (p
);
1987 /* Rewrite the PARM_DECL's type with its component. */
1988 TREE_TYPE (p
) = subtype
;
1989 DECL_ARG_TYPE (p
) = TREE_TYPE (DECL_ARG_TYPE (p
));
1990 DECL_MODE (p
) = VOIDmode
;
1991 DECL_SIZE (p
) = NULL
;
1992 DECL_SIZE_UNIT (p
) = NULL
;
1993 /* If this arg must go in memory, put it in a pseudo here.
1994 We can't allow it to go in memory as per normal parms,
1995 because the usual place might not have the imag part
1996 adjacent to the real part. */
1997 DECL_ARTIFICIAL (p
) = addressable
;
1998 DECL_IGNORED_P (p
) = addressable
;
1999 TREE_ADDRESSABLE (p
) = 0;
2002 /* Build a second synthetic decl. */
2003 decl
= build_decl (PARM_DECL
, NULL_TREE
, subtype
);
2004 DECL_ARG_TYPE (decl
) = DECL_ARG_TYPE (p
);
2005 DECL_ARTIFICIAL (decl
) = addressable
;
2006 DECL_IGNORED_P (decl
) = addressable
;
2007 layout_decl (decl
, 0);
2009 /* Splice it in; skip the new decl. */
2010 TREE_CHAIN (decl
) = TREE_CHAIN (p
);
2011 TREE_CHAIN (p
) = decl
;
2019 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
2020 the hidden struct return argument, and (abi willing) complex args.
2021 Return the new parameter list. */
2024 assign_parms_augmented_arg_list (struct assign_parm_data_all
*all
)
2026 tree fndecl
= current_function_decl
;
2027 tree fntype
= TREE_TYPE (fndecl
);
2028 tree fnargs
= DECL_ARGUMENTS (fndecl
);
2030 /* If struct value address is treated as the first argument, make it so. */
2031 if (aggregate_value_p (DECL_RESULT (fndecl
), fndecl
)
2032 && ! cfun
->returns_pcc_struct
2033 && targetm
.calls
.struct_value_rtx (TREE_TYPE (fndecl
), 1) == 0)
2035 tree type
= build_pointer_type (TREE_TYPE (fntype
));
2038 decl
= build_decl (PARM_DECL
, NULL_TREE
, type
);
2039 DECL_ARG_TYPE (decl
) = type
;
2040 DECL_ARTIFICIAL (decl
) = 1;
2041 DECL_IGNORED_P (decl
) = 1;
2043 TREE_CHAIN (decl
) = fnargs
;
2045 all
->function_result_decl
= decl
;
2048 all
->orig_fnargs
= fnargs
;
2050 /* If the target wants to split complex arguments into scalars, do so. */
2051 if (targetm
.calls
.split_complex_arg
)
2052 fnargs
= split_complex_args (fnargs
);
2057 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2058 data for the parameter. Incorporate ABI specifics such as pass-by-
2059 reference and type promotion. */
2062 assign_parm_find_data_types (struct assign_parm_data_all
*all
, tree parm
,
2063 struct assign_parm_data_one
*data
)
2065 tree nominal_type
, passed_type
;
2066 enum machine_mode nominal_mode
, passed_mode
, promoted_mode
;
2068 memset (data
, 0, sizeof (*data
));
2070 /* NAMED_ARG is a misnomer. We really mean 'non-variadic'. */
2072 data
->named_arg
= 1; /* No variadic parms. */
2073 else if (TREE_CHAIN (parm
))
2074 data
->named_arg
= 1; /* Not the last non-variadic parm. */
2075 else if (targetm
.calls
.strict_argument_naming (&all
->args_so_far
))
2076 data
->named_arg
= 1; /* Only variadic ones are unnamed. */
2078 data
->named_arg
= 0; /* Treat as variadic. */
2080 nominal_type
= TREE_TYPE (parm
);
2081 passed_type
= DECL_ARG_TYPE (parm
);
2083 /* Look out for errors propagating this far. Also, if the parameter's
2084 type is void then its value doesn't matter. */
2085 if (TREE_TYPE (parm
) == error_mark_node
2086 /* This can happen after weird syntax errors
2087 or if an enum type is defined among the parms. */
2088 || TREE_CODE (parm
) != PARM_DECL
2089 || passed_type
== NULL
2090 || VOID_TYPE_P (nominal_type
))
2092 nominal_type
= passed_type
= void_type_node
;
2093 nominal_mode
= passed_mode
= promoted_mode
= VOIDmode
;
2097 /* Find mode of arg as it is passed, and mode of arg as it should be
2098 during execution of this function. */
2099 passed_mode
= TYPE_MODE (passed_type
);
2100 nominal_mode
= TYPE_MODE (nominal_type
);
2102 /* If the parm is to be passed as a transparent union, use the type of
2103 the first field for the tests below. We have already verified that
2104 the modes are the same. */
2105 if (TREE_CODE (passed_type
) == UNION_TYPE
2106 && TYPE_TRANSPARENT_UNION (passed_type
))
2107 passed_type
= TREE_TYPE (TYPE_FIELDS (passed_type
));
2109 /* See if this arg was passed by invisible reference. */
2110 if (pass_by_reference (&all
->args_so_far
, passed_mode
,
2111 passed_type
, data
->named_arg
))
2113 passed_type
= nominal_type
= build_pointer_type (passed_type
);
2114 data
->passed_pointer
= true;
2115 passed_mode
= nominal_mode
= Pmode
;
2118 /* Find mode as it is passed by the ABI. */
2119 promoted_mode
= passed_mode
;
2120 if (targetm
.calls
.promote_function_args (TREE_TYPE (current_function_decl
)))
2122 int unsignedp
= TYPE_UNSIGNED (passed_type
);
2123 promoted_mode
= promote_mode (passed_type
, promoted_mode
,
2128 data
->nominal_type
= nominal_type
;
2129 data
->passed_type
= passed_type
;
2130 data
->nominal_mode
= nominal_mode
;
2131 data
->passed_mode
= passed_mode
;
2132 data
->promoted_mode
= promoted_mode
;
2135 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2138 assign_parms_setup_varargs (struct assign_parm_data_all
*all
,
2139 struct assign_parm_data_one
*data
, bool no_rtl
)
2141 int varargs_pretend_bytes
= 0;
2143 targetm
.calls
.setup_incoming_varargs (&all
->args_so_far
,
2144 data
->promoted_mode
,
2146 &varargs_pretend_bytes
, no_rtl
);
2148 /* If the back-end has requested extra stack space, record how much is
2149 needed. Do not change pretend_args_size otherwise since it may be
2150 nonzero from an earlier partial argument. */
2151 if (varargs_pretend_bytes
> 0)
2152 all
->pretend_args_size
= varargs_pretend_bytes
;
2155 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2156 the incoming location of the current parameter. */
2159 assign_parm_find_entry_rtl (struct assign_parm_data_all
*all
,
2160 struct assign_parm_data_one
*data
)
2162 HOST_WIDE_INT pretend_bytes
= 0;
2166 if (data
->promoted_mode
== VOIDmode
)
2168 data
->entry_parm
= data
->stack_parm
= const0_rtx
;
2172 #ifdef FUNCTION_INCOMING_ARG
2173 entry_parm
= FUNCTION_INCOMING_ARG (all
->args_so_far
, data
->promoted_mode
,
2174 data
->passed_type
, data
->named_arg
);
2176 entry_parm
= FUNCTION_ARG (all
->args_so_far
, data
->promoted_mode
,
2177 data
->passed_type
, data
->named_arg
);
2180 if (entry_parm
== 0)
2181 data
->promoted_mode
= data
->passed_mode
;
2183 /* Determine parm's home in the stack, in case it arrives in the stack
2184 or we should pretend it did. Compute the stack position and rtx where
2185 the argument arrives and its size.
2187 There is one complexity here: If this was a parameter that would
2188 have been passed in registers, but wasn't only because it is
2189 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2190 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2191 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2192 as it was the previous time. */
2193 in_regs
= entry_parm
!= 0;
2194 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2197 if (!in_regs
&& !data
->named_arg
)
2199 if (targetm
.calls
.pretend_outgoing_varargs_named (&all
->args_so_far
))
2202 #ifdef FUNCTION_INCOMING_ARG
2203 tem
= FUNCTION_INCOMING_ARG (all
->args_so_far
, data
->promoted_mode
,
2204 data
->passed_type
, true);
2206 tem
= FUNCTION_ARG (all
->args_so_far
, data
->promoted_mode
,
2207 data
->passed_type
, true);
2209 in_regs
= tem
!= NULL
;
2213 /* If this parameter was passed both in registers and in the stack, use
2214 the copy on the stack. */
2215 if (targetm
.calls
.must_pass_in_stack (data
->promoted_mode
,
2223 partial
= targetm
.calls
.arg_partial_bytes (&all
->args_so_far
,
2224 data
->promoted_mode
,
2227 data
->partial
= partial
;
2229 /* The caller might already have allocated stack space for the
2230 register parameters. */
2231 if (partial
!= 0 && all
->reg_parm_stack_space
== 0)
2233 /* Part of this argument is passed in registers and part
2234 is passed on the stack. Ask the prologue code to extend
2235 the stack part so that we can recreate the full value.
2237 PRETEND_BYTES is the size of the registers we need to store.
2238 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2239 stack space that the prologue should allocate.
2241 Internally, gcc assumes that the argument pointer is aligned
2242 to STACK_BOUNDARY bits. This is used both for alignment
2243 optimizations (see init_emit) and to locate arguments that are
2244 aligned to more than PARM_BOUNDARY bits. We must preserve this
2245 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2246 a stack boundary. */
2248 /* We assume at most one partial arg, and it must be the first
2249 argument on the stack. */
2250 gcc_assert (!all
->extra_pretend_bytes
&& !all
->pretend_args_size
);
2252 pretend_bytes
= partial
;
2253 all
->pretend_args_size
= CEIL_ROUND (pretend_bytes
, STACK_BYTES
);
2255 /* We want to align relative to the actual stack pointer, so
2256 don't include this in the stack size until later. */
2257 all
->extra_pretend_bytes
= all
->pretend_args_size
;
2261 locate_and_pad_parm (data
->promoted_mode
, data
->passed_type
, in_regs
,
2262 entry_parm
? data
->partial
: 0, current_function_decl
,
2263 &all
->stack_args_size
, &data
->locate
);
2265 /* Update parm_stack_boundary if this parameter is passed in the
2267 if (!in_regs
&& crtl
->parm_stack_boundary
< data
->locate
.boundary
)
2268 crtl
->parm_stack_boundary
= data
->locate
.boundary
;
2270 /* Adjust offsets to include the pretend args. */
2271 pretend_bytes
= all
->extra_pretend_bytes
- pretend_bytes
;
2272 data
->locate
.slot_offset
.constant
+= pretend_bytes
;
2273 data
->locate
.offset
.constant
+= pretend_bytes
;
2275 data
->entry_parm
= entry_parm
;
2278 /* A subroutine of assign_parms. If there is actually space on the stack
2279 for this parm, count it in stack_args_size and return true. */
2282 assign_parm_is_stack_parm (struct assign_parm_data_all
*all
,
2283 struct assign_parm_data_one
*data
)
2285 /* Trivially true if we've no incoming register. */
2286 if (data
->entry_parm
== NULL
)
2288 /* Also true if we're partially in registers and partially not,
2289 since we've arranged to drop the entire argument on the stack. */
2290 else if (data
->partial
!= 0)
2292 /* Also true if the target says that it's passed in both registers
2293 and on the stack. */
2294 else if (GET_CODE (data
->entry_parm
) == PARALLEL
2295 && XEXP (XVECEXP (data
->entry_parm
, 0, 0), 0) == NULL_RTX
)
2297 /* Also true if the target says that there's stack allocated for
2298 all register parameters. */
2299 else if (all
->reg_parm_stack_space
> 0)
2301 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2305 all
->stack_args_size
.constant
+= data
->locate
.size
.constant
;
2306 if (data
->locate
.size
.var
)
2307 ADD_PARM_SIZE (all
->stack_args_size
, data
->locate
.size
.var
);
2312 /* A subroutine of assign_parms. Given that this parameter is allocated
2313 stack space by the ABI, find it. */
2316 assign_parm_find_stack_rtl (tree parm
, struct assign_parm_data_one
*data
)
2318 rtx offset_rtx
, stack_parm
;
2319 unsigned int align
, boundary
;
2321 /* If we're passing this arg using a reg, make its stack home the
2322 aligned stack slot. */
2323 if (data
->entry_parm
)
2324 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.slot_offset
);
2326 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.offset
);
2328 stack_parm
= crtl
->args
.internal_arg_pointer
;
2329 if (offset_rtx
!= const0_rtx
)
2330 stack_parm
= gen_rtx_PLUS (Pmode
, stack_parm
, offset_rtx
);
2331 stack_parm
= gen_rtx_MEM (data
->promoted_mode
, stack_parm
);
2333 set_mem_attributes (stack_parm
, parm
, 1);
2335 boundary
= data
->locate
.boundary
;
2336 align
= BITS_PER_UNIT
;
2338 /* If we're padding upward, we know that the alignment of the slot
2339 is FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2340 intentionally forcing upward padding. Otherwise we have to come
2341 up with a guess at the alignment based on OFFSET_RTX. */
2342 if (data
->locate
.where_pad
!= downward
|| data
->entry_parm
)
2344 else if (GET_CODE (offset_rtx
) == CONST_INT
)
2346 align
= INTVAL (offset_rtx
) * BITS_PER_UNIT
| boundary
;
2347 align
= align
& -align
;
2349 set_mem_align (stack_parm
, align
);
2351 if (data
->entry_parm
)
2352 set_reg_attrs_for_parm (data
->entry_parm
, stack_parm
);
2354 data
->stack_parm
= stack_parm
;
2357 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2358 always valid and contiguous. */
2361 assign_parm_adjust_entry_rtl (struct assign_parm_data_one
*data
)
2363 rtx entry_parm
= data
->entry_parm
;
2364 rtx stack_parm
= data
->stack_parm
;
2366 /* If this parm was passed part in regs and part in memory, pretend it
2367 arrived entirely in memory by pushing the register-part onto the stack.
2368 In the special case of a DImode or DFmode that is split, we could put
2369 it together in a pseudoreg directly, but for now that's not worth
2371 if (data
->partial
!= 0)
2373 /* Handle calls that pass values in multiple non-contiguous
2374 locations. The Irix 6 ABI has examples of this. */
2375 if (GET_CODE (entry_parm
) == PARALLEL
)
2376 emit_group_store (validize_mem (stack_parm
), entry_parm
,
2378 int_size_in_bytes (data
->passed_type
));
2381 gcc_assert (data
->partial
% UNITS_PER_WORD
== 0);
2382 move_block_from_reg (REGNO (entry_parm
), validize_mem (stack_parm
),
2383 data
->partial
/ UNITS_PER_WORD
);
2386 entry_parm
= stack_parm
;
2389 /* If we didn't decide this parm came in a register, by default it came
2391 else if (entry_parm
== NULL
)
2392 entry_parm
= stack_parm
;
2394 /* When an argument is passed in multiple locations, we can't make use
2395 of this information, but we can save some copying if the whole argument
2396 is passed in a single register. */
2397 else if (GET_CODE (entry_parm
) == PARALLEL
2398 && data
->nominal_mode
!= BLKmode
2399 && data
->passed_mode
!= BLKmode
)
2401 size_t i
, len
= XVECLEN (entry_parm
, 0);
2403 for (i
= 0; i
< len
; i
++)
2404 if (XEXP (XVECEXP (entry_parm
, 0, i
), 0) != NULL_RTX
2405 && REG_P (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2406 && (GET_MODE (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2407 == data
->passed_mode
)
2408 && INTVAL (XEXP (XVECEXP (entry_parm
, 0, i
), 1)) == 0)
2410 entry_parm
= XEXP (XVECEXP (entry_parm
, 0, i
), 0);
2415 data
->entry_parm
= entry_parm
;
2418 /* A subroutine of assign_parms. Reconstitute any values which were
2419 passed in multiple registers and would fit in a single register. */
2422 assign_parm_remove_parallels (struct assign_parm_data_one
*data
)
2424 rtx entry_parm
= data
->entry_parm
;
2426 /* Convert the PARALLEL to a REG of the same mode as the parallel.
2427 This can be done with register operations rather than on the
2428 stack, even if we will store the reconstituted parameter on the
2430 if (GET_CODE (entry_parm
) == PARALLEL
&& GET_MODE (entry_parm
) != BLKmode
)
2432 rtx parmreg
= gen_reg_rtx (GET_MODE (entry_parm
));
2433 emit_group_store (parmreg
, entry_parm
, NULL_TREE
,
2434 GET_MODE_SIZE (GET_MODE (entry_parm
)));
2435 entry_parm
= parmreg
;
2438 data
->entry_parm
= entry_parm
;
2441 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2442 always valid and properly aligned. */
2445 assign_parm_adjust_stack_rtl (struct assign_parm_data_one
*data
)
2447 rtx stack_parm
= data
->stack_parm
;
2449 /* If we can't trust the parm stack slot to be aligned enough for its
2450 ultimate type, don't use that slot after entry. We'll make another
2451 stack slot, if we need one. */
2453 && ((STRICT_ALIGNMENT
2454 && GET_MODE_ALIGNMENT (data
->nominal_mode
) > MEM_ALIGN (stack_parm
))
2455 || (data
->nominal_type
2456 && TYPE_ALIGN (data
->nominal_type
) > MEM_ALIGN (stack_parm
)
2457 && MEM_ALIGN (stack_parm
) < PREFERRED_STACK_BOUNDARY
)))
2460 /* If parm was passed in memory, and we need to convert it on entry,
2461 don't store it back in that same slot. */
2462 else if (data
->entry_parm
== stack_parm
2463 && data
->nominal_mode
!= BLKmode
2464 && data
->nominal_mode
!= data
->passed_mode
)
2467 /* If stack protection is in effect for this function, don't leave any
2468 pointers in their passed stack slots. */
2469 else if (crtl
->stack_protect_guard
2470 && (flag_stack_protect
== 2
2471 || data
->passed_pointer
2472 || POINTER_TYPE_P (data
->nominal_type
)))
2475 data
->stack_parm
= stack_parm
;
2478 /* A subroutine of assign_parms. Return true if the current parameter
2479 should be stored as a BLKmode in the current frame. */
2482 assign_parm_setup_block_p (struct assign_parm_data_one
*data
)
2484 if (data
->nominal_mode
== BLKmode
)
2486 if (GET_MODE (data
->entry_parm
) == BLKmode
)
2489 #ifdef BLOCK_REG_PADDING
2490 /* Only assign_parm_setup_block knows how to deal with register arguments
2491 that are padded at the least significant end. */
2492 if (REG_P (data
->entry_parm
)
2493 && GET_MODE_SIZE (data
->promoted_mode
) < UNITS_PER_WORD
2494 && (BLOCK_REG_PADDING (data
->passed_mode
, data
->passed_type
, 1)
2495 == (BYTES_BIG_ENDIAN
? upward
: downward
)))
2502 /* A subroutine of assign_parms. Arrange for the parameter to be
2503 present and valid in DATA->STACK_RTL. */
2506 assign_parm_setup_block (struct assign_parm_data_all
*all
,
2507 tree parm
, struct assign_parm_data_one
*data
)
2509 rtx entry_parm
= data
->entry_parm
;
2510 rtx stack_parm
= data
->stack_parm
;
2512 HOST_WIDE_INT size_stored
;
2514 if (GET_CODE (entry_parm
) == PARALLEL
)
2515 entry_parm
= emit_group_move_into_temps (entry_parm
);
2517 size
= int_size_in_bytes (data
->passed_type
);
2518 size_stored
= CEIL_ROUND (size
, UNITS_PER_WORD
);
2519 if (stack_parm
== 0)
2521 DECL_ALIGN (parm
) = MAX (DECL_ALIGN (parm
), BITS_PER_WORD
);
2522 stack_parm
= assign_stack_local (BLKmode
, size_stored
,
2524 if (GET_MODE_SIZE (GET_MODE (entry_parm
)) == size
)
2525 PUT_MODE (stack_parm
, GET_MODE (entry_parm
));
2526 set_mem_attributes (stack_parm
, parm
, 1);
2529 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2530 calls that pass values in multiple non-contiguous locations. */
2531 if (REG_P (entry_parm
) || GET_CODE (entry_parm
) == PARALLEL
)
2535 /* Note that we will be storing an integral number of words.
2536 So we have to be careful to ensure that we allocate an
2537 integral number of words. We do this above when we call
2538 assign_stack_local if space was not allocated in the argument
2539 list. If it was, this will not work if PARM_BOUNDARY is not
2540 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2541 if it becomes a problem. Exception is when BLKmode arrives
2542 with arguments not conforming to word_mode. */
2544 if (data
->stack_parm
== 0)
2546 else if (GET_CODE (entry_parm
) == PARALLEL
)
2549 gcc_assert (!size
|| !(PARM_BOUNDARY
% BITS_PER_WORD
));
2551 mem
= validize_mem (stack_parm
);
2553 /* Handle values in multiple non-contiguous locations. */
2554 if (GET_CODE (entry_parm
) == PARALLEL
)
2556 push_to_sequence2 (all
->first_conversion_insn
,
2557 all
->last_conversion_insn
);
2558 emit_group_store (mem
, entry_parm
, data
->passed_type
, size
);
2559 all
->first_conversion_insn
= get_insns ();
2560 all
->last_conversion_insn
= get_last_insn ();
2567 /* If SIZE is that of a mode no bigger than a word, just use
2568 that mode's store operation. */
2569 else if (size
<= UNITS_PER_WORD
)
2571 enum machine_mode mode
2572 = mode_for_size (size
* BITS_PER_UNIT
, MODE_INT
, 0);
2575 #ifdef BLOCK_REG_PADDING
2576 && (size
== UNITS_PER_WORD
2577 || (BLOCK_REG_PADDING (mode
, data
->passed_type
, 1)
2578 != (BYTES_BIG_ENDIAN
? upward
: downward
)))
2584 /* We are really truncating a word_mode value containing
2585 SIZE bytes into a value of mode MODE. If such an
2586 operation requires no actual instructions, we can refer
2587 to the value directly in mode MODE, otherwise we must
2588 start with the register in word_mode and explicitly
2590 if (TRULY_NOOP_TRUNCATION (size
* BITS_PER_UNIT
, BITS_PER_WORD
))
2591 reg
= gen_rtx_REG (mode
, REGNO (entry_parm
));
2594 reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
2595 reg
= convert_to_mode (mode
, copy_to_reg (reg
), 1);
2597 emit_move_insn (change_address (mem
, mode
, 0), reg
);
2600 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
2601 machine must be aligned to the left before storing
2602 to memory. Note that the previous test doesn't
2603 handle all cases (e.g. SIZE == 3). */
2604 else if (size
!= UNITS_PER_WORD
2605 #ifdef BLOCK_REG_PADDING
2606 && (BLOCK_REG_PADDING (mode
, data
->passed_type
, 1)
2614 int by
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
2615 rtx reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
2617 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
,
2618 build_int_cst (NULL_TREE
, by
),
2620 tem
= change_address (mem
, word_mode
, 0);
2621 emit_move_insn (tem
, x
);
2624 move_block_from_reg (REGNO (entry_parm
), mem
,
2625 size_stored
/ UNITS_PER_WORD
);
2628 move_block_from_reg (REGNO (entry_parm
), mem
,
2629 size_stored
/ UNITS_PER_WORD
);
2631 else if (data
->stack_parm
== 0)
2633 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2634 emit_block_move (stack_parm
, data
->entry_parm
, GEN_INT (size
),
2636 all
->first_conversion_insn
= get_insns ();
2637 all
->last_conversion_insn
= get_last_insn ();
2641 data
->stack_parm
= stack_parm
;
2642 SET_DECL_RTL (parm
, stack_parm
);
2645 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
2646 parameter. Get it there. Perform all ABI specified conversions. */
2649 assign_parm_setup_reg (struct assign_parm_data_all
*all
, tree parm
,
2650 struct assign_parm_data_one
*data
)
2653 enum machine_mode promoted_nominal_mode
;
2654 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (parm
));
2655 bool did_conversion
= false;
2657 /* Store the parm in a pseudoregister during the function, but we may
2658 need to do it in a wider mode. */
2660 /* This is not really promoting for a call. However we need to be
2661 consistent with assign_parm_find_data_types and expand_expr_real_1. */
2662 promoted_nominal_mode
2663 = promote_mode (data
->nominal_type
, data
->nominal_mode
, &unsignedp
, 1);
2665 parmreg
= gen_reg_rtx (promoted_nominal_mode
);
2667 if (!DECL_ARTIFICIAL (parm
))
2668 mark_user_reg (parmreg
);
2670 /* If this was an item that we received a pointer to,
2671 set DECL_RTL appropriately. */
2672 if (data
->passed_pointer
)
2674 rtx x
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data
->passed_type
)), parmreg
);
2675 set_mem_attributes (x
, parm
, 1);
2676 SET_DECL_RTL (parm
, x
);
2679 SET_DECL_RTL (parm
, parmreg
);
2681 assign_parm_remove_parallels (data
);
2683 /* Copy the value into the register. */
2684 if (data
->nominal_mode
!= data
->passed_mode
2685 || promoted_nominal_mode
!= data
->promoted_mode
)
2689 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
2690 mode, by the caller. We now have to convert it to
2691 NOMINAL_MODE, if different. However, PARMREG may be in
2692 a different mode than NOMINAL_MODE if it is being stored
2695 If ENTRY_PARM is a hard register, it might be in a register
2696 not valid for operating in its mode (e.g., an odd-numbered
2697 register for a DFmode). In that case, moves are the only
2698 thing valid, so we can't do a convert from there. This
2699 occurs when the calling sequence allow such misaligned
2702 In addition, the conversion may involve a call, which could
2703 clobber parameters which haven't been copied to pseudo
2704 registers yet. Therefore, we must first copy the parm to
2705 a pseudo reg here, and save the conversion until after all
2706 parameters have been moved. */
2708 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
2710 emit_move_insn (tempreg
, validize_mem (data
->entry_parm
));
2712 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2713 tempreg
= convert_to_mode (data
->nominal_mode
, tempreg
, unsignedp
);
2715 if (GET_CODE (tempreg
) == SUBREG
2716 && GET_MODE (tempreg
) == data
->nominal_mode
2717 && REG_P (SUBREG_REG (tempreg
))
2718 && data
->nominal_mode
== data
->passed_mode
2719 && GET_MODE (SUBREG_REG (tempreg
)) == GET_MODE (data
->entry_parm
)
2720 && GET_MODE_SIZE (GET_MODE (tempreg
))
2721 < GET_MODE_SIZE (GET_MODE (data
->entry_parm
)))
2723 /* The argument is already sign/zero extended, so note it
2725 SUBREG_PROMOTED_VAR_P (tempreg
) = 1;
2726 SUBREG_PROMOTED_UNSIGNED_SET (tempreg
, unsignedp
);
2729 /* TREE_USED gets set erroneously during expand_assignment. */
2730 save_tree_used
= TREE_USED (parm
);
2731 expand_assignment (parm
, make_tree (data
->nominal_type
, tempreg
), false);
2732 TREE_USED (parm
) = save_tree_used
;
2733 all
->first_conversion_insn
= get_insns ();
2734 all
->last_conversion_insn
= get_last_insn ();
2737 did_conversion
= true;
2740 emit_move_insn (parmreg
, validize_mem (data
->entry_parm
));
2742 /* If we were passed a pointer but the actual value can safely live
2743 in a register, put it in one. */
2744 if (data
->passed_pointer
2745 && TYPE_MODE (TREE_TYPE (parm
)) != BLKmode
2746 /* If by-reference argument was promoted, demote it. */
2747 && (TYPE_MODE (TREE_TYPE (parm
)) != GET_MODE (DECL_RTL (parm
))
2748 || use_register_for_decl (parm
)))
2750 /* We can't use nominal_mode, because it will have been set to
2751 Pmode above. We must use the actual mode of the parm. */
2752 parmreg
= gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm
)));
2753 mark_user_reg (parmreg
);
2755 if (GET_MODE (parmreg
) != GET_MODE (DECL_RTL (parm
)))
2757 rtx tempreg
= gen_reg_rtx (GET_MODE (DECL_RTL (parm
)));
2758 int unsigned_p
= TYPE_UNSIGNED (TREE_TYPE (parm
));
2760 push_to_sequence2 (all
->first_conversion_insn
,
2761 all
->last_conversion_insn
);
2762 emit_move_insn (tempreg
, DECL_RTL (parm
));
2763 tempreg
= convert_to_mode (GET_MODE (parmreg
), tempreg
, unsigned_p
);
2764 emit_move_insn (parmreg
, tempreg
);
2765 all
->first_conversion_insn
= get_insns ();
2766 all
->last_conversion_insn
= get_last_insn ();
2769 did_conversion
= true;
2772 emit_move_insn (parmreg
, DECL_RTL (parm
));
2774 SET_DECL_RTL (parm
, parmreg
);
2776 /* STACK_PARM is the pointer, not the parm, and PARMREG is
2778 data
->stack_parm
= NULL
;
2781 /* Mark the register as eliminable if we did no conversion and it was
2782 copied from memory at a fixed offset, and the arg pointer was not
2783 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
2784 offset formed an invalid address, such memory-equivalences as we
2785 make here would screw up life analysis for it. */
2786 if (data
->nominal_mode
== data
->passed_mode
2788 && data
->stack_parm
!= 0
2789 && MEM_P (data
->stack_parm
)
2790 && data
->locate
.offset
.var
== 0
2791 && reg_mentioned_p (virtual_incoming_args_rtx
,
2792 XEXP (data
->stack_parm
, 0)))
2794 rtx linsn
= get_last_insn ();
2797 /* Mark complex types separately. */
2798 if (GET_CODE (parmreg
) == CONCAT
)
2800 enum machine_mode submode
2801 = GET_MODE_INNER (GET_MODE (parmreg
));
2802 int regnor
= REGNO (XEXP (parmreg
, 0));
2803 int regnoi
= REGNO (XEXP (parmreg
, 1));
2804 rtx stackr
= adjust_address_nv (data
->stack_parm
, submode
, 0);
2805 rtx stacki
= adjust_address_nv (data
->stack_parm
, submode
,
2806 GET_MODE_SIZE (submode
));
2808 /* Scan backwards for the set of the real and
2810 for (sinsn
= linsn
; sinsn
!= 0;
2811 sinsn
= prev_nonnote_insn (sinsn
))
2813 set
= single_set (sinsn
);
2817 if (SET_DEST (set
) == regno_reg_rtx
[regnoi
])
2818 set_unique_reg_note (sinsn
, REG_EQUIV
, stacki
);
2819 else if (SET_DEST (set
) == regno_reg_rtx
[regnor
])
2820 set_unique_reg_note (sinsn
, REG_EQUIV
, stackr
);
2823 else if ((set
= single_set (linsn
)) != 0
2824 && SET_DEST (set
) == parmreg
)
2825 set_unique_reg_note (linsn
, REG_EQUIV
, data
->stack_parm
);
2828 /* For pointer data type, suggest pointer register. */
2829 if (POINTER_TYPE_P (TREE_TYPE (parm
)))
2830 mark_reg_pointer (parmreg
,
2831 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
2834 /* A subroutine of assign_parms. Allocate stack space to hold the current
2835 parameter. Get it there. Perform all ABI specified conversions. */
2838 assign_parm_setup_stack (struct assign_parm_data_all
*all
, tree parm
,
2839 struct assign_parm_data_one
*data
)
2841 /* Value must be stored in the stack slot STACK_PARM during function
2843 bool to_conversion
= false;
2845 assign_parm_remove_parallels (data
);
2847 if (data
->promoted_mode
!= data
->nominal_mode
)
2849 /* Conversion is required. */
2850 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
2852 emit_move_insn (tempreg
, validize_mem (data
->entry_parm
));
2854 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2855 to_conversion
= true;
2857 data
->entry_parm
= convert_to_mode (data
->nominal_mode
, tempreg
,
2858 TYPE_UNSIGNED (TREE_TYPE (parm
)));
2860 if (data
->stack_parm
)
2861 /* ??? This may need a big-endian conversion on sparc64. */
2863 = adjust_address (data
->stack_parm
, data
->nominal_mode
, 0);
2866 if (data
->entry_parm
!= data
->stack_parm
)
2870 if (data
->stack_parm
== 0)
2873 = assign_stack_local (GET_MODE (data
->entry_parm
),
2874 GET_MODE_SIZE (GET_MODE (data
->entry_parm
)),
2875 TYPE_ALIGN (data
->passed_type
));
2876 set_mem_attributes (data
->stack_parm
, parm
, 1);
2879 dest
= validize_mem (data
->stack_parm
);
2880 src
= validize_mem (data
->entry_parm
);
2884 /* Use a block move to handle potentially misaligned entry_parm. */
2886 push_to_sequence2 (all
->first_conversion_insn
,
2887 all
->last_conversion_insn
);
2888 to_conversion
= true;
2890 emit_block_move (dest
, src
,
2891 GEN_INT (int_size_in_bytes (data
->passed_type
)),
2895 emit_move_insn (dest
, src
);
2900 all
->first_conversion_insn
= get_insns ();
2901 all
->last_conversion_insn
= get_last_insn ();
2905 SET_DECL_RTL (parm
, data
->stack_parm
);
2908 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
2909 undo the frobbing that we did in assign_parms_augmented_arg_list. */
2912 assign_parms_unsplit_complex (struct assign_parm_data_all
*all
, tree fnargs
)
2915 tree orig_fnargs
= all
->orig_fnargs
;
2917 for (parm
= orig_fnargs
; parm
; parm
= TREE_CHAIN (parm
))
2919 if (TREE_CODE (TREE_TYPE (parm
)) == COMPLEX_TYPE
2920 && targetm
.calls
.split_complex_arg (TREE_TYPE (parm
)))
2922 rtx tmp
, real
, imag
;
2923 enum machine_mode inner
= GET_MODE_INNER (DECL_MODE (parm
));
2925 real
= DECL_RTL (fnargs
);
2926 imag
= DECL_RTL (TREE_CHAIN (fnargs
));
2927 if (inner
!= GET_MODE (real
))
2929 real
= gen_lowpart_SUBREG (inner
, real
);
2930 imag
= gen_lowpart_SUBREG (inner
, imag
);
2933 if (TREE_ADDRESSABLE (parm
))
2936 HOST_WIDE_INT size
= int_size_in_bytes (TREE_TYPE (parm
));
2938 /* split_complex_arg put the real and imag parts in
2939 pseudos. Move them to memory. */
2940 tmp
= assign_stack_local (DECL_MODE (parm
), size
,
2941 TYPE_ALIGN (TREE_TYPE (parm
)));
2942 set_mem_attributes (tmp
, parm
, 1);
2943 rmem
= adjust_address_nv (tmp
, inner
, 0);
2944 imem
= adjust_address_nv (tmp
, inner
, GET_MODE_SIZE (inner
));
2945 push_to_sequence2 (all
->first_conversion_insn
,
2946 all
->last_conversion_insn
);
2947 emit_move_insn (rmem
, real
);
2948 emit_move_insn (imem
, imag
);
2949 all
->first_conversion_insn
= get_insns ();
2950 all
->last_conversion_insn
= get_last_insn ();
2954 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
2955 SET_DECL_RTL (parm
, tmp
);
2957 real
= DECL_INCOMING_RTL (fnargs
);
2958 imag
= DECL_INCOMING_RTL (TREE_CHAIN (fnargs
));
2959 if (inner
!= GET_MODE (real
))
2961 real
= gen_lowpart_SUBREG (inner
, real
);
2962 imag
= gen_lowpart_SUBREG (inner
, imag
);
2964 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
2965 set_decl_incoming_rtl (parm
, tmp
, false);
2966 fnargs
= TREE_CHAIN (fnargs
);
2970 SET_DECL_RTL (parm
, DECL_RTL (fnargs
));
2971 set_decl_incoming_rtl (parm
, DECL_INCOMING_RTL (fnargs
), false);
2973 /* Set MEM_EXPR to the original decl, i.e. to PARM,
2974 instead of the copy of decl, i.e. FNARGS. */
2975 if (DECL_INCOMING_RTL (parm
) && MEM_P (DECL_INCOMING_RTL (parm
)))
2976 set_mem_expr (DECL_INCOMING_RTL (parm
), parm
);
2979 fnargs
= TREE_CHAIN (fnargs
);
2983 /* Assign RTL expressions to the function's parameters. This may involve
2984 copying them into registers and using those registers as the DECL_RTL. */
2987 assign_parms (tree fndecl
)
2989 struct assign_parm_data_all all
;
2992 crtl
->args
.internal_arg_pointer
2993 = targetm
.calls
.internal_arg_pointer ();
2995 assign_parms_initialize_all (&all
);
2996 fnargs
= assign_parms_augmented_arg_list (&all
);
2998 for (parm
= fnargs
; parm
; parm
= TREE_CHAIN (parm
))
3000 struct assign_parm_data_one data
;
3002 /* Extract the type of PARM; adjust it according to ABI. */
3003 assign_parm_find_data_types (&all
, parm
, &data
);
3005 /* Early out for errors and void parameters. */
3006 if (data
.passed_mode
== VOIDmode
)
3008 SET_DECL_RTL (parm
, const0_rtx
);
3009 DECL_INCOMING_RTL (parm
) = DECL_RTL (parm
);
3013 /* Estimate stack alignment from parameter alignment. */
3014 if (SUPPORTS_STACK_ALIGNMENT
)
3016 unsigned int align
= FUNCTION_ARG_BOUNDARY (data
.promoted_mode
,
3018 if (TYPE_ALIGN (data
.nominal_type
) > align
)
3019 align
= TYPE_ALIGN (data
.passed_type
);
3020 if (crtl
->stack_alignment_estimated
< align
)
3022 gcc_assert (!crtl
->stack_realign_processed
);
3023 crtl
->stack_alignment_estimated
= align
;
3027 if (cfun
->stdarg
&& !TREE_CHAIN (parm
))
3028 assign_parms_setup_varargs (&all
, &data
, false);
3030 /* Find out where the parameter arrives in this function. */
3031 assign_parm_find_entry_rtl (&all
, &data
);
3033 /* Find out where stack space for this parameter might be. */
3034 if (assign_parm_is_stack_parm (&all
, &data
))
3036 assign_parm_find_stack_rtl (parm
, &data
);
3037 assign_parm_adjust_entry_rtl (&data
);
3040 /* Record permanently how this parm was passed. */
3041 set_decl_incoming_rtl (parm
, data
.entry_parm
, data
.passed_pointer
);
3043 /* Update info on where next arg arrives in registers. */
3044 FUNCTION_ARG_ADVANCE (all
.args_so_far
, data
.promoted_mode
,
3045 data
.passed_type
, data
.named_arg
);
3047 assign_parm_adjust_stack_rtl (&data
);
3049 if (assign_parm_setup_block_p (&data
))
3050 assign_parm_setup_block (&all
, parm
, &data
);
3051 else if (data
.passed_pointer
|| use_register_for_decl (parm
))
3052 assign_parm_setup_reg (&all
, parm
, &data
);
3054 assign_parm_setup_stack (&all
, parm
, &data
);
3057 if (targetm
.calls
.split_complex_arg
&& fnargs
!= all
.orig_fnargs
)
3058 assign_parms_unsplit_complex (&all
, fnargs
);
3060 /* Output all parameter conversion instructions (possibly including calls)
3061 now that all parameters have been copied out of hard registers. */
3062 emit_insn (all
.first_conversion_insn
);
3064 /* Estimate reload stack alignment from scalar return mode. */
3065 if (SUPPORTS_STACK_ALIGNMENT
)
3067 if (DECL_RESULT (fndecl
))
3069 tree type
= TREE_TYPE (DECL_RESULT (fndecl
));
3070 enum machine_mode mode
= TYPE_MODE (type
);
3074 && !AGGREGATE_TYPE_P (type
))
3076 unsigned int align
= GET_MODE_ALIGNMENT (mode
);
3077 if (crtl
->stack_alignment_estimated
< align
)
3079 gcc_assert (!crtl
->stack_realign_processed
);
3080 crtl
->stack_alignment_estimated
= align
;
3086 /* If we are receiving a struct value address as the first argument, set up
3087 the RTL for the function result. As this might require code to convert
3088 the transmitted address to Pmode, we do this here to ensure that possible
3089 preliminary conversions of the address have been emitted already. */
3090 if (all
.function_result_decl
)
3092 tree result
= DECL_RESULT (current_function_decl
);
3093 rtx addr
= DECL_RTL (all
.function_result_decl
);
3096 if (DECL_BY_REFERENCE (result
))
3100 addr
= convert_memory_address (Pmode
, addr
);
3101 x
= gen_rtx_MEM (DECL_MODE (result
), addr
);
3102 set_mem_attributes (x
, result
, 1);
3104 SET_DECL_RTL (result
, x
);
3107 /* We have aligned all the args, so add space for the pretend args. */
3108 crtl
->args
.pretend_args_size
= all
.pretend_args_size
;
3109 all
.stack_args_size
.constant
+= all
.extra_pretend_bytes
;
3110 crtl
->args
.size
= all
.stack_args_size
.constant
;
3112 /* Adjust function incoming argument size for alignment and
3115 #ifdef REG_PARM_STACK_SPACE
3116 crtl
->args
.size
= MAX (crtl
->args
.size
,
3117 REG_PARM_STACK_SPACE (fndecl
));
3120 crtl
->args
.size
= CEIL_ROUND (crtl
->args
.size
,
3121 PARM_BOUNDARY
/ BITS_PER_UNIT
);
3123 #ifdef ARGS_GROW_DOWNWARD
3124 crtl
->args
.arg_offset_rtx
3125 = (all
.stack_args_size
.var
== 0 ? GEN_INT (-all
.stack_args_size
.constant
)
3126 : expand_expr (size_diffop (all
.stack_args_size
.var
,
3127 size_int (-all
.stack_args_size
.constant
)),
3128 NULL_RTX
, VOIDmode
, 0));
3130 crtl
->args
.arg_offset_rtx
= ARGS_SIZE_RTX (all
.stack_args_size
);
3133 /* See how many bytes, if any, of its args a function should try to pop
3136 crtl
->args
.pops_args
= RETURN_POPS_ARGS (fndecl
, TREE_TYPE (fndecl
),
3139 /* For stdarg.h function, save info about
3140 regs and stack space used by the named args. */
3142 crtl
->args
.info
= all
.args_so_far
;
3144 /* Set the rtx used for the function return value. Put this in its
3145 own variable so any optimizers that need this information don't have
3146 to include tree.h. Do this here so it gets done when an inlined
3147 function gets output. */
3150 = (DECL_RTL_SET_P (DECL_RESULT (fndecl
))
3151 ? DECL_RTL (DECL_RESULT (fndecl
)) : NULL_RTX
);
3153 /* If scalar return value was computed in a pseudo-reg, or was a named
3154 return value that got dumped to the stack, copy that to the hard
3156 if (DECL_RTL_SET_P (DECL_RESULT (fndecl
)))
3158 tree decl_result
= DECL_RESULT (fndecl
);
3159 rtx decl_rtl
= DECL_RTL (decl_result
);
3161 if (REG_P (decl_rtl
)
3162 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
3163 : DECL_REGISTER (decl_result
))
3167 real_decl_rtl
= targetm
.calls
.function_value (TREE_TYPE (decl_result
),
3169 REG_FUNCTION_VALUE_P (real_decl_rtl
) = 1;
3170 /* The delay slot scheduler assumes that crtl->return_rtx
3171 holds the hard register containing the return value, not a
3172 temporary pseudo. */
3173 crtl
->return_rtx
= real_decl_rtl
;
3178 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3179 For all seen types, gimplify their sizes. */
3182 gimplify_parm_type (tree
*tp
, int *walk_subtrees
, void *data
)
3189 if (POINTER_TYPE_P (t
))
3191 else if (TYPE_SIZE (t
) && !TREE_CONSTANT (TYPE_SIZE (t
))
3192 && !TYPE_SIZES_GIMPLIFIED (t
))
3194 gimplify_type_sizes (t
, (gimple_seq
*) data
);
3202 /* Gimplify the parameter list for current_function_decl. This involves
3203 evaluating SAVE_EXPRs of variable sized parameters and generating code
3204 to implement callee-copies reference parameters. Returns a sequence of
3205 statements to add to the beginning of the function. */
3208 gimplify_parameters (void)
3210 struct assign_parm_data_all all
;
3212 gimple_seq stmts
= NULL
;
3214 assign_parms_initialize_all (&all
);
3215 fnargs
= assign_parms_augmented_arg_list (&all
);
3217 for (parm
= fnargs
; parm
; parm
= TREE_CHAIN (parm
))
3219 struct assign_parm_data_one data
;
3221 /* Extract the type of PARM; adjust it according to ABI. */
3222 assign_parm_find_data_types (&all
, parm
, &data
);
3224 /* Early out for errors and void parameters. */
3225 if (data
.passed_mode
== VOIDmode
|| DECL_SIZE (parm
) == NULL
)
3228 /* Update info on where next arg arrives in registers. */
3229 FUNCTION_ARG_ADVANCE (all
.args_so_far
, data
.promoted_mode
,
3230 data
.passed_type
, data
.named_arg
);
3232 /* ??? Once upon a time variable_size stuffed parameter list
3233 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3234 turned out to be less than manageable in the gimple world.
3235 Now we have to hunt them down ourselves. */
3236 walk_tree_without_duplicates (&data
.passed_type
,
3237 gimplify_parm_type
, &stmts
);
3239 if (!TREE_CONSTANT (DECL_SIZE (parm
)))
3241 gimplify_one_sizepos (&DECL_SIZE (parm
), &stmts
);
3242 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm
), &stmts
);
3245 if (data
.passed_pointer
)
3247 tree type
= TREE_TYPE (data
.passed_type
);
3248 if (reference_callee_copied (&all
.args_so_far
, TYPE_MODE (type
),
3249 type
, data
.named_arg
))
3253 /* For constant sized objects, this is trivial; for
3254 variable-sized objects, we have to play games. */
3255 if (TREE_CONSTANT (DECL_SIZE (parm
)))
3257 local
= create_tmp_var (type
, get_name (parm
));
3258 DECL_IGNORED_P (local
) = 0;
3262 tree ptr_type
, addr
;
3264 ptr_type
= build_pointer_type (type
);
3265 addr
= create_tmp_var (ptr_type
, get_name (parm
));
3266 DECL_IGNORED_P (addr
) = 0;
3267 local
= build_fold_indirect_ref (addr
);
3269 t
= built_in_decls
[BUILT_IN_ALLOCA
];
3270 t
= build_call_expr (t
, 1, DECL_SIZE_UNIT (parm
));
3271 t
= fold_convert (ptr_type
, t
);
3272 t
= build2 (MODIFY_EXPR
, TREE_TYPE (addr
), addr
, t
);
3273 gimplify_and_add (t
, &stmts
);
3276 gimplify_assign (local
, parm
, &stmts
);
3278 SET_DECL_VALUE_EXPR (parm
, local
);
3279 DECL_HAS_VALUE_EXPR_P (parm
) = 1;
3287 /* Compute the size and offset from the start of the stacked arguments for a
3288 parm passed in mode PASSED_MODE and with type TYPE.
3290 INITIAL_OFFSET_PTR points to the current offset into the stacked
3293 The starting offset and size for this parm are returned in
3294 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3295 nonzero, the offset is that of stack slot, which is returned in
3296 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3297 padding required from the initial offset ptr to the stack slot.
3299 IN_REGS is nonzero if the argument will be passed in registers. It will
3300 never be set if REG_PARM_STACK_SPACE is not defined.
3302 FNDECL is the function in which the argument was defined.
3304 There are two types of rounding that are done. The first, controlled by
3305 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
3306 list to be aligned to the specific boundary (in bits). This rounding
3307 affects the initial and starting offsets, but not the argument size.
3309 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3310 optionally rounds the size of the parm to PARM_BOUNDARY. The
3311 initial offset is not affected by this rounding, while the size always
3312 is and the starting offset may be. */
3314 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3315 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3316 callers pass in the total size of args so far as
3317 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
3320 locate_and_pad_parm (enum machine_mode passed_mode
, tree type
, int in_regs
,
3321 int partial
, tree fndecl ATTRIBUTE_UNUSED
,
3322 struct args_size
*initial_offset_ptr
,
3323 struct locate_and_pad_arg_data
*locate
)
3326 enum direction where_pad
;
3327 unsigned int boundary
;
3328 int reg_parm_stack_space
= 0;
3329 int part_size_in_regs
;
3331 #ifdef REG_PARM_STACK_SPACE
3332 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
3334 /* If we have found a stack parm before we reach the end of the
3335 area reserved for registers, skip that area. */
3338 if (reg_parm_stack_space
> 0)
3340 if (initial_offset_ptr
->var
)
3342 initial_offset_ptr
->var
3343 = size_binop (MAX_EXPR
, ARGS_SIZE_TREE (*initial_offset_ptr
),
3344 ssize_int (reg_parm_stack_space
));
3345 initial_offset_ptr
->constant
= 0;
3347 else if (initial_offset_ptr
->constant
< reg_parm_stack_space
)
3348 initial_offset_ptr
->constant
= reg_parm_stack_space
;
3351 #endif /* REG_PARM_STACK_SPACE */
3353 part_size_in_regs
= (reg_parm_stack_space
== 0 ? partial
: 0);
3356 = type
? size_in_bytes (type
) : size_int (GET_MODE_SIZE (passed_mode
));
3357 where_pad
= FUNCTION_ARG_PADDING (passed_mode
, type
);
3358 boundary
= FUNCTION_ARG_BOUNDARY (passed_mode
, type
);
3359 locate
->where_pad
= where_pad
;
3361 /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT. */
3362 if (boundary
> MAX_SUPPORTED_STACK_ALIGNMENT
)
3363 boundary
= MAX_SUPPORTED_STACK_ALIGNMENT
;
3365 locate
->boundary
= boundary
;
3367 if (SUPPORTS_STACK_ALIGNMENT
)
3369 /* stack_alignment_estimated can't change after stack has been
3371 if (crtl
->stack_alignment_estimated
< boundary
)
3373 if (!crtl
->stack_realign_processed
)
3374 crtl
->stack_alignment_estimated
= boundary
;
3377 /* If stack is realigned and stack alignment value
3378 hasn't been finalized, it is OK not to increase
3379 stack_alignment_estimated. The bigger alignment
3380 requirement is recorded in stack_alignment_needed
3382 gcc_assert (!crtl
->stack_realign_finalized
3383 && crtl
->stack_realign_needed
);
3388 /* Remember if the outgoing parameter requires extra alignment on the
3389 calling function side. */
3390 if (crtl
->stack_alignment_needed
< boundary
)
3391 crtl
->stack_alignment_needed
= boundary
;
3392 if (crtl
->max_used_stack_slot_alignment
< crtl
->stack_alignment_needed
)
3393 crtl
->max_used_stack_slot_alignment
= crtl
->stack_alignment_needed
;
3394 if (crtl
->preferred_stack_boundary
< boundary
)
3395 crtl
->preferred_stack_boundary
= boundary
;
3397 #ifdef ARGS_GROW_DOWNWARD
3398 locate
->slot_offset
.constant
= -initial_offset_ptr
->constant
;
3399 if (initial_offset_ptr
->var
)
3400 locate
->slot_offset
.var
= size_binop (MINUS_EXPR
, ssize_int (0),
3401 initial_offset_ptr
->var
);
3405 if (where_pad
!= none
3406 && (!host_integerp (sizetree
, 1)
3407 || (tree_low_cst (sizetree
, 1) * BITS_PER_UNIT
) % PARM_BOUNDARY
))
3408 s2
= round_up (s2
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3409 SUB_PARM_SIZE (locate
->slot_offset
, s2
);
3412 locate
->slot_offset
.constant
+= part_size_in_regs
;
3415 #ifdef REG_PARM_STACK_SPACE
3416 || REG_PARM_STACK_SPACE (fndecl
) > 0
3419 pad_to_arg_alignment (&locate
->slot_offset
, boundary
,
3420 &locate
->alignment_pad
);
3422 locate
->size
.constant
= (-initial_offset_ptr
->constant
3423 - locate
->slot_offset
.constant
);
3424 if (initial_offset_ptr
->var
)
3425 locate
->size
.var
= size_binop (MINUS_EXPR
,
3426 size_binop (MINUS_EXPR
,
3428 initial_offset_ptr
->var
),
3429 locate
->slot_offset
.var
);
3431 /* Pad_below needs the pre-rounded size to know how much to pad
3433 locate
->offset
= locate
->slot_offset
;
3434 if (where_pad
== downward
)
3435 pad_below (&locate
->offset
, passed_mode
, sizetree
);
3437 #else /* !ARGS_GROW_DOWNWARD */
3439 #ifdef REG_PARM_STACK_SPACE
3440 || REG_PARM_STACK_SPACE (fndecl
) > 0
3443 pad_to_arg_alignment (initial_offset_ptr
, boundary
,
3444 &locate
->alignment_pad
);
3445 locate
->slot_offset
= *initial_offset_ptr
;
3447 #ifdef PUSH_ROUNDING
3448 if (passed_mode
!= BLKmode
)
3449 sizetree
= size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree
)));
3452 /* Pad_below needs the pre-rounded size to know how much to pad below
3453 so this must be done before rounding up. */
3454 locate
->offset
= locate
->slot_offset
;
3455 if (where_pad
== downward
)
3456 pad_below (&locate
->offset
, passed_mode
, sizetree
);
3458 if (where_pad
!= none
3459 && (!host_integerp (sizetree
, 1)
3460 || (tree_low_cst (sizetree
, 1) * BITS_PER_UNIT
) % PARM_BOUNDARY
))
3461 sizetree
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3463 ADD_PARM_SIZE (locate
->size
, sizetree
);
3465 locate
->size
.constant
-= part_size_in_regs
;
3466 #endif /* ARGS_GROW_DOWNWARD */
3469 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
3470 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
3473 pad_to_arg_alignment (struct args_size
*offset_ptr
, int boundary
,
3474 struct args_size
*alignment_pad
)
3476 tree save_var
= NULL_TREE
;
3477 HOST_WIDE_INT save_constant
= 0;
3478 int boundary_in_bytes
= boundary
/ BITS_PER_UNIT
;
3479 HOST_WIDE_INT sp_offset
= STACK_POINTER_OFFSET
;
3481 #ifdef SPARC_STACK_BOUNDARY_HACK
3482 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
3483 the real alignment of %sp. However, when it does this, the
3484 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
3485 if (SPARC_STACK_BOUNDARY_HACK
)
3489 if (boundary
> PARM_BOUNDARY
)
3491 save_var
= offset_ptr
->var
;
3492 save_constant
= offset_ptr
->constant
;
3495 alignment_pad
->var
= NULL_TREE
;
3496 alignment_pad
->constant
= 0;
3498 if (boundary
> BITS_PER_UNIT
)
3500 if (offset_ptr
->var
)
3502 tree sp_offset_tree
= ssize_int (sp_offset
);
3503 tree offset
= size_binop (PLUS_EXPR
,
3504 ARGS_SIZE_TREE (*offset_ptr
),
3506 #ifdef ARGS_GROW_DOWNWARD
3507 tree rounded
= round_down (offset
, boundary
/ BITS_PER_UNIT
);
3509 tree rounded
= round_up (offset
, boundary
/ BITS_PER_UNIT
);
3512 offset_ptr
->var
= size_binop (MINUS_EXPR
, rounded
, sp_offset_tree
);
3513 /* ARGS_SIZE_TREE includes constant term. */
3514 offset_ptr
->constant
= 0;
3515 if (boundary
> PARM_BOUNDARY
)
3516 alignment_pad
->var
= size_binop (MINUS_EXPR
, offset_ptr
->var
,
3521 offset_ptr
->constant
= -sp_offset
+
3522 #ifdef ARGS_GROW_DOWNWARD
3523 FLOOR_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
3525 CEIL_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
3527 if (boundary
> PARM_BOUNDARY
)
3528 alignment_pad
->constant
= offset_ptr
->constant
- save_constant
;
3534 pad_below (struct args_size
*offset_ptr
, enum machine_mode passed_mode
, tree sizetree
)
3536 if (passed_mode
!= BLKmode
)
3538 if (GET_MODE_BITSIZE (passed_mode
) % PARM_BOUNDARY
)
3539 offset_ptr
->constant
3540 += (((GET_MODE_BITSIZE (passed_mode
) + PARM_BOUNDARY
- 1)
3541 / PARM_BOUNDARY
* PARM_BOUNDARY
/ BITS_PER_UNIT
)
3542 - GET_MODE_SIZE (passed_mode
));
3546 if (TREE_CODE (sizetree
) != INTEGER_CST
3547 || (TREE_INT_CST_LOW (sizetree
) * BITS_PER_UNIT
) % PARM_BOUNDARY
)
3549 /* Round the size up to multiple of PARM_BOUNDARY bits. */
3550 tree s2
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3552 ADD_PARM_SIZE (*offset_ptr
, s2
);
3553 SUB_PARM_SIZE (*offset_ptr
, sizetree
);
3559 /* True if register REGNO was alive at a place where `setjmp' was
3560 called and was set more than once or is an argument. Such regs may
3561 be clobbered by `longjmp'. */
3564 regno_clobbered_at_setjmp (bitmap setjmp_crosses
, int regno
)
3566 /* There appear to be cases where some local vars never reach the
3567 backend but have bogus regnos. */
3568 if (regno
>= max_reg_num ())
3571 return ((REG_N_SETS (regno
) > 1
3572 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR
), regno
))
3573 && REGNO_REG_SET_P (setjmp_crosses
, regno
));
3576 /* Walk the tree of blocks describing the binding levels within a
3577 function and warn about variables the might be killed by setjmp or
3578 vfork. This is done after calling flow_analysis before register
3579 allocation since that will clobber the pseudo-regs to hard
3583 setjmp_vars_warning (bitmap setjmp_crosses
, tree block
)
3587 for (decl
= BLOCK_VARS (block
); decl
; decl
= TREE_CHAIN (decl
))
3589 if (TREE_CODE (decl
) == VAR_DECL
3590 && DECL_RTL_SET_P (decl
)
3591 && REG_P (DECL_RTL (decl
))
3592 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
3593 warning (OPT_Wclobbered
, "variable %q+D might be clobbered by"
3594 " %<longjmp%> or %<vfork%>", decl
);
3597 for (sub
= BLOCK_SUBBLOCKS (block
); sub
; sub
= BLOCK_CHAIN (sub
))
3598 setjmp_vars_warning (setjmp_crosses
, sub
);
3601 /* Do the appropriate part of setjmp_vars_warning
3602 but for arguments instead of local variables. */
3605 setjmp_args_warning (bitmap setjmp_crosses
)
3608 for (decl
= DECL_ARGUMENTS (current_function_decl
);
3609 decl
; decl
= TREE_CHAIN (decl
))
3610 if (DECL_RTL (decl
) != 0
3611 && REG_P (DECL_RTL (decl
))
3612 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
3613 warning (OPT_Wclobbered
,
3614 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
3618 /* Generate warning messages for variables live across setjmp. */
3621 generate_setjmp_warnings (void)
3623 bitmap setjmp_crosses
= regstat_get_setjmp_crosses ();
3625 if (n_basic_blocks
== NUM_FIXED_BLOCKS
3626 || bitmap_empty_p (setjmp_crosses
))
3629 setjmp_vars_warning (setjmp_crosses
, DECL_INITIAL (current_function_decl
));
3630 setjmp_args_warning (setjmp_crosses
);
3634 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
3635 and create duplicate blocks. */
3636 /* ??? Need an option to either create block fragments or to create
3637 abstract origin duplicates of a source block. It really depends
3638 on what optimization has been performed. */
3641 reorder_blocks (void)
3643 tree block
= DECL_INITIAL (current_function_decl
);
3644 VEC(tree
,heap
) *block_stack
;
3646 if (block
== NULL_TREE
)
3649 block_stack
= VEC_alloc (tree
, heap
, 10);
3651 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
3652 clear_block_marks (block
);
3654 /* Prune the old trees away, so that they don't get in the way. */
3655 BLOCK_SUBBLOCKS (block
) = NULL_TREE
;
3656 BLOCK_CHAIN (block
) = NULL_TREE
;
3658 /* Recreate the block tree from the note nesting. */
3659 reorder_blocks_1 (get_insns (), block
, &block_stack
);
3660 BLOCK_SUBBLOCKS (block
) = blocks_nreverse (BLOCK_SUBBLOCKS (block
));
3662 VEC_free (tree
, heap
, block_stack
);
3665 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
3668 clear_block_marks (tree block
)
3672 TREE_ASM_WRITTEN (block
) = 0;
3673 clear_block_marks (BLOCK_SUBBLOCKS (block
));
3674 block
= BLOCK_CHAIN (block
);
3679 reorder_blocks_1 (rtx insns
, tree current_block
, VEC(tree
,heap
) **p_block_stack
)
3683 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
3687 if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_BEG
)
3689 tree block
= NOTE_BLOCK (insn
);
3692 origin
= (BLOCK_FRAGMENT_ORIGIN (block
)
3693 ? BLOCK_FRAGMENT_ORIGIN (block
)
3696 /* If we have seen this block before, that means it now
3697 spans multiple address regions. Create a new fragment. */
3698 if (TREE_ASM_WRITTEN (block
))
3700 tree new_block
= copy_node (block
);
3702 BLOCK_FRAGMENT_ORIGIN (new_block
) = origin
;
3703 BLOCK_FRAGMENT_CHAIN (new_block
)
3704 = BLOCK_FRAGMENT_CHAIN (origin
);
3705 BLOCK_FRAGMENT_CHAIN (origin
) = new_block
;
3707 NOTE_BLOCK (insn
) = new_block
;
3711 BLOCK_SUBBLOCKS (block
) = 0;
3712 TREE_ASM_WRITTEN (block
) = 1;
3713 /* When there's only one block for the entire function,
3714 current_block == block and we mustn't do this, it
3715 will cause infinite recursion. */
3716 if (block
!= current_block
)
3718 if (block
!= origin
)
3719 gcc_assert (BLOCK_SUPERCONTEXT (origin
) == current_block
);
3721 BLOCK_SUPERCONTEXT (block
) = current_block
;
3722 BLOCK_CHAIN (block
) = BLOCK_SUBBLOCKS (current_block
);
3723 BLOCK_SUBBLOCKS (current_block
) = block
;
3724 current_block
= origin
;
3726 VEC_safe_push (tree
, heap
, *p_block_stack
, block
);
3728 else if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_END
)
3730 NOTE_BLOCK (insn
) = VEC_pop (tree
, *p_block_stack
);
3731 BLOCK_SUBBLOCKS (current_block
)
3732 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block
));
3733 current_block
= BLOCK_SUPERCONTEXT (current_block
);
3739 /* Reverse the order of elements in the chain T of blocks,
3740 and return the new head of the chain (old last element). */
3743 blocks_nreverse (tree t
)
3745 tree prev
= 0, decl
, next
;
3746 for (decl
= t
; decl
; decl
= next
)
3748 next
= BLOCK_CHAIN (decl
);
3749 BLOCK_CHAIN (decl
) = prev
;
3755 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
3756 non-NULL, list them all into VECTOR, in a depth-first preorder
3757 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
3761 all_blocks (tree block
, tree
*vector
)
3767 TREE_ASM_WRITTEN (block
) = 0;
3769 /* Record this block. */
3771 vector
[n_blocks
] = block
;
3775 /* Record the subblocks, and their subblocks... */
3776 n_blocks
+= all_blocks (BLOCK_SUBBLOCKS (block
),
3777 vector
? vector
+ n_blocks
: 0);
3778 block
= BLOCK_CHAIN (block
);
3784 /* Return a vector containing all the blocks rooted at BLOCK. The
3785 number of elements in the vector is stored in N_BLOCKS_P. The
3786 vector is dynamically allocated; it is the caller's responsibility
3787 to call `free' on the pointer returned. */
3790 get_block_vector (tree block
, int *n_blocks_p
)
3794 *n_blocks_p
= all_blocks (block
, NULL
);
3795 block_vector
= XNEWVEC (tree
, *n_blocks_p
);
3796 all_blocks (block
, block_vector
);
3798 return block_vector
;
3801 static GTY(()) int next_block_index
= 2;
3803 /* Set BLOCK_NUMBER for all the blocks in FN. */
3806 number_blocks (tree fn
)
3812 /* For SDB and XCOFF debugging output, we start numbering the blocks
3813 from 1 within each function, rather than keeping a running
3815 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
3816 if (write_symbols
== SDB_DEBUG
|| write_symbols
== XCOFF_DEBUG
)
3817 next_block_index
= 1;
3820 block_vector
= get_block_vector (DECL_INITIAL (fn
), &n_blocks
);
3822 /* The top-level BLOCK isn't numbered at all. */
3823 for (i
= 1; i
< n_blocks
; ++i
)
3824 /* We number the blocks from two. */
3825 BLOCK_NUMBER (block_vector
[i
]) = next_block_index
++;
3827 free (block_vector
);
3832 /* If VAR is present in a subblock of BLOCK, return the subblock. */
3835 debug_find_var_in_block_tree (tree var
, tree block
)
3839 for (t
= BLOCK_VARS (block
); t
; t
= TREE_CHAIN (t
))
3843 for (t
= BLOCK_SUBBLOCKS (block
); t
; t
= TREE_CHAIN (t
))
3845 tree ret
= debug_find_var_in_block_tree (var
, t
);
3853 /* Keep track of whether we're in a dummy function context. If we are,
3854 we don't want to invoke the set_current_function hook, because we'll
3855 get into trouble if the hook calls target_reinit () recursively or
3856 when the initial initialization is not yet complete. */
3858 static bool in_dummy_function
;
3860 /* Invoke the target hook when setting cfun. Update the optimization options
3861 if the function uses different options than the default. */
3864 invoke_set_current_function_hook (tree fndecl
)
3866 if (!in_dummy_function
)
3868 tree opts
= ((fndecl
)
3869 ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl
)
3870 : optimization_default_node
);
3873 opts
= optimization_default_node
;
3875 /* Change optimization options if needed. */
3876 if (optimization_current_node
!= opts
)
3878 optimization_current_node
= opts
;
3879 cl_optimization_restore (TREE_OPTIMIZATION (opts
));
3882 targetm
.set_current_function (fndecl
);
3886 /* cfun should never be set directly; use this function. */
3889 set_cfun (struct function
*new_cfun
)
3891 if (cfun
!= new_cfun
)
3894 invoke_set_current_function_hook (new_cfun
? new_cfun
->decl
: NULL_TREE
);
3898 /* Keep track of the cfun stack. */
3900 typedef struct function
*function_p
;
3902 DEF_VEC_P(function_p
);
3903 DEF_VEC_ALLOC_P(function_p
,heap
);
3905 /* Initialized with NOGC, making this poisonous to the garbage collector. */
3907 static VEC(function_p
,heap
) *cfun_stack
;
3909 /* Push the current cfun onto the stack, and set cfun to new_cfun. */
3912 push_cfun (struct function
*new_cfun
)
3914 VEC_safe_push (function_p
, heap
, cfun_stack
, cfun
);
3915 set_cfun (new_cfun
);
3918 /* Pop cfun from the stack. */
3923 struct function
*new_cfun
= VEC_pop (function_p
, cfun_stack
);
3924 set_cfun (new_cfun
);
3927 /* Return value of funcdef and increase it. */
3929 get_next_funcdef_no (void)
3931 return funcdef_no
++;
3934 /* Allocate a function structure for FNDECL and set its contents
3935 to the defaults. Set cfun to the newly-allocated object.
3936 Some of the helper functions invoked during initialization assume
3937 that cfun has already been set. Therefore, assign the new object
3938 directly into cfun and invoke the back end hook explicitly at the
3939 very end, rather than initializing a temporary and calling set_cfun
3942 ABSTRACT_P is true if this is a function that will never be seen by
3943 the middle-end. Such functions are front-end concepts (like C++
3944 function templates) that do not correspond directly to functions
3945 placed in object files. */
3948 allocate_struct_function (tree fndecl
, bool abstract_p
)
3951 tree fntype
= fndecl
? TREE_TYPE (fndecl
) : NULL_TREE
;
3953 cfun
= GGC_CNEW (struct function
);
3955 cfun
->function_frequency
= FUNCTION_FREQUENCY_NORMAL
;
3957 init_eh_for_function ();
3959 if (init_machine_status
)
3960 cfun
->machine
= (*init_machine_status
) ();
3962 #ifdef OVERRIDE_ABI_FORMAT
3963 OVERRIDE_ABI_FORMAT (fndecl
);
3966 if (fndecl
!= NULL_TREE
)
3968 DECL_STRUCT_FUNCTION (fndecl
) = cfun
;
3969 cfun
->decl
= fndecl
;
3970 current_function_funcdef_no
= get_next_funcdef_no ();
3972 result
= DECL_RESULT (fndecl
);
3973 if (!abstract_p
&& aggregate_value_p (result
, fndecl
))
3975 #ifdef PCC_STATIC_STRUCT_RETURN
3976 cfun
->returns_pcc_struct
= 1;
3978 cfun
->returns_struct
= 1;
3983 && TYPE_ARG_TYPES (fntype
) != 0
3984 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype
)))
3985 != void_type_node
));
3987 /* Assume all registers in stdarg functions need to be saved. */
3988 cfun
->va_list_gpr_size
= VA_LIST_MAX_GPR_SIZE
;
3989 cfun
->va_list_fpr_size
= VA_LIST_MAX_FPR_SIZE
;
3992 invoke_set_current_function_hook (fndecl
);
3995 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
3996 instead of just setting it. */
3999 push_struct_function (tree fndecl
)
4001 VEC_safe_push (function_p
, heap
, cfun_stack
, cfun
);
4002 allocate_struct_function (fndecl
, false);
4005 /* Reset cfun, and other non-struct-function variables to defaults as
4006 appropriate for emitting rtl at the start of a function. */
4009 prepare_function_start (void)
4011 gcc_assert (!crtl
->emit
.x_last_insn
);
4013 init_varasm_status ();
4015 default_rtl_profile ();
4017 cse_not_expected
= ! optimize
;
4019 /* Caller save not needed yet. */
4020 caller_save_needed
= 0;
4022 /* We haven't done register allocation yet. */
4025 /* Indicate that we have not instantiated virtual registers yet. */
4026 virtuals_instantiated
= 0;
4028 /* Indicate that we want CONCATs now. */
4029 generating_concat_p
= 1;
4031 /* Indicate we have no need of a frame pointer yet. */
4032 frame_pointer_needed
= 0;
4035 /* Initialize the rtl expansion mechanism so that we can do simple things
4036 like generate sequences. This is used to provide a context during global
4037 initialization of some passes. You must call expand_dummy_function_end
4038 to exit this context. */
4041 init_dummy_function_start (void)
4043 gcc_assert (!in_dummy_function
);
4044 in_dummy_function
= true;
4045 push_struct_function (NULL_TREE
);
4046 prepare_function_start ();
4049 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
4050 and initialize static variables for generating RTL for the statements
4054 init_function_start (tree subr
)
4056 if (subr
&& DECL_STRUCT_FUNCTION (subr
))
4057 set_cfun (DECL_STRUCT_FUNCTION (subr
));
4059 allocate_struct_function (subr
, false);
4060 prepare_function_start ();
4062 /* Warn if this value is an aggregate type,
4063 regardless of which calling convention we are using for it. */
4064 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr
))))
4065 warning (OPT_Waggregate_return
, "function returns an aggregate");
4068 /* Make sure all values used by the optimization passes have sane
4071 init_function_for_compilation (void)
4075 /* No prologue/epilogue insns yet. Make sure that these vectors are
4077 gcc_assert (VEC_length (int, prologue
) == 0);
4078 gcc_assert (VEC_length (int, epilogue
) == 0);
4079 gcc_assert (VEC_length (int, sibcall_epilogue
) == 0);
4083 struct rtl_opt_pass pass_init_function
=
4089 init_function_for_compilation
, /* execute */
4092 0, /* static_pass_number */
4094 0, /* properties_required */
4095 0, /* properties_provided */
4096 0, /* properties_destroyed */
4097 0, /* todo_flags_start */
4098 0 /* todo_flags_finish */
4104 expand_main_function (void)
4106 #if (defined(INVOKE__main) \
4107 || (!defined(HAS_INIT_SECTION) \
4108 && !defined(INIT_SECTION_ASM_OP) \
4109 && !defined(INIT_ARRAY_SECTION_ASM_OP)))
4110 emit_library_call (init_one_libfunc (NAME__MAIN
), LCT_NORMAL
, VOIDmode
, 0);
4114 /* Expand code to initialize the stack_protect_guard. This is invoked at
4115 the beginning of a function to be protected. */
4117 #ifndef HAVE_stack_protect_set
4118 # define HAVE_stack_protect_set 0
4119 # define gen_stack_protect_set(x,y) (gcc_unreachable (), NULL_RTX)
4123 stack_protect_prologue (void)
4125 tree guard_decl
= targetm
.stack_protect_guard ();
4128 /* Avoid expand_expr here, because we don't want guard_decl pulled
4129 into registers unless absolutely necessary. And we know that
4130 crtl->stack_protect_guard is a local stack slot, so this skips
4132 x
= validize_mem (DECL_RTL (crtl
->stack_protect_guard
));
4133 y
= validize_mem (DECL_RTL (guard_decl
));
4135 /* Allow the target to copy from Y to X without leaking Y into a
4137 if (HAVE_stack_protect_set
)
4139 rtx insn
= gen_stack_protect_set (x
, y
);
4147 /* Otherwise do a straight move. */
4148 emit_move_insn (x
, y
);
4151 /* Expand code to verify the stack_protect_guard. This is invoked at
4152 the end of a function to be protected. */
4154 #ifndef HAVE_stack_protect_test
4155 # define HAVE_stack_protect_test 0
4156 # define gen_stack_protect_test(x, y, z) (gcc_unreachable (), NULL_RTX)
4160 stack_protect_epilogue (void)
4162 tree guard_decl
= targetm
.stack_protect_guard ();
4163 rtx label
= gen_label_rtx ();
4166 /* Avoid expand_expr here, because we don't want guard_decl pulled
4167 into registers unless absolutely necessary. And we know that
4168 crtl->stack_protect_guard is a local stack slot, so this skips
4170 x
= validize_mem (DECL_RTL (crtl
->stack_protect_guard
));
4171 y
= validize_mem (DECL_RTL (guard_decl
));
4173 /* Allow the target to compare Y with X without leaking either into
4175 switch (HAVE_stack_protect_test
!= 0)
4178 tmp
= gen_stack_protect_test (x
, y
, label
);
4187 emit_cmp_and_jump_insns (x
, y
, EQ
, NULL_RTX
, ptr_mode
, 1, label
);
4191 /* The noreturn predictor has been moved to the tree level. The rtl-level
4192 predictors estimate this branch about 20%, which isn't enough to get
4193 things moved out of line. Since this is the only extant case of adding
4194 a noreturn function at the rtl level, it doesn't seem worth doing ought
4195 except adding the prediction by hand. */
4196 tmp
= get_last_insn ();
4198 predict_insn_def (tmp
, PRED_NORETURN
, TAKEN
);
4200 expand_expr_stmt (targetm
.stack_protect_fail ());
4204 /* Start the RTL for a new function, and set variables used for
4206 SUBR is the FUNCTION_DECL node.
4207 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4208 the function's parameters, which must be run at any return statement. */
4211 expand_function_start (tree subr
)
4213 /* Make sure volatile mem refs aren't considered
4214 valid operands of arithmetic insns. */
4215 init_recog_no_volatile ();
4219 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr
));
4222 = (stack_limit_rtx
!= NULL_RTX
&& ! DECL_NO_LIMIT_STACK (subr
));
4224 /* Make the label for return statements to jump to. Do not special
4225 case machines with special return instructions -- they will be
4226 handled later during jump, ifcvt, or epilogue creation. */
4227 return_label
= gen_label_rtx ();
4229 /* Initialize rtx used to return the value. */
4230 /* Do this before assign_parms so that we copy the struct value address
4231 before any library calls that assign parms might generate. */
4233 /* Decide whether to return the value in memory or in a register. */
4234 if (aggregate_value_p (DECL_RESULT (subr
), subr
))
4236 /* Returning something that won't go in a register. */
4237 rtx value_address
= 0;
4239 #ifdef PCC_STATIC_STRUCT_RETURN
4240 if (cfun
->returns_pcc_struct
)
4242 int size
= int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr
)));
4243 value_address
= assemble_static_space (size
);
4248 rtx sv
= targetm
.calls
.struct_value_rtx (TREE_TYPE (subr
), 2);
4249 /* Expect to be passed the address of a place to store the value.
4250 If it is passed as an argument, assign_parms will take care of
4254 value_address
= gen_reg_rtx (Pmode
);
4255 emit_move_insn (value_address
, sv
);
4260 rtx x
= value_address
;
4261 if (!DECL_BY_REFERENCE (DECL_RESULT (subr
)))
4263 x
= gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr
)), x
);
4264 set_mem_attributes (x
, DECL_RESULT (subr
), 1);
4266 SET_DECL_RTL (DECL_RESULT (subr
), x
);
4269 else if (DECL_MODE (DECL_RESULT (subr
)) == VOIDmode
)
4270 /* If return mode is void, this decl rtl should not be used. */
4271 SET_DECL_RTL (DECL_RESULT (subr
), NULL_RTX
);
4274 /* Compute the return values into a pseudo reg, which we will copy
4275 into the true return register after the cleanups are done. */
4276 tree return_type
= TREE_TYPE (DECL_RESULT (subr
));
4277 if (TYPE_MODE (return_type
) != BLKmode
4278 && targetm
.calls
.return_in_msb (return_type
))
4279 /* expand_function_end will insert the appropriate padding in
4280 this case. Use the return value's natural (unpadded) mode
4281 within the function proper. */
4282 SET_DECL_RTL (DECL_RESULT (subr
),
4283 gen_reg_rtx (TYPE_MODE (return_type
)));
4286 /* In order to figure out what mode to use for the pseudo, we
4287 figure out what the mode of the eventual return register will
4288 actually be, and use that. */
4289 rtx hard_reg
= hard_function_value (return_type
, subr
, 0, 1);
4291 /* Structures that are returned in registers are not
4292 aggregate_value_p, so we may see a PARALLEL or a REG. */
4293 if (REG_P (hard_reg
))
4294 SET_DECL_RTL (DECL_RESULT (subr
),
4295 gen_reg_rtx (GET_MODE (hard_reg
)));
4298 gcc_assert (GET_CODE (hard_reg
) == PARALLEL
);
4299 SET_DECL_RTL (DECL_RESULT (subr
), gen_group_rtx (hard_reg
));
4303 /* Set DECL_REGISTER flag so that expand_function_end will copy the
4304 result to the real return register(s). */
4305 DECL_REGISTER (DECL_RESULT (subr
)) = 1;
4308 /* Initialize rtx for parameters and local variables.
4309 In some cases this requires emitting insns. */
4310 assign_parms (subr
);
4312 /* If function gets a static chain arg, store it. */
4313 if (cfun
->static_chain_decl
)
4315 tree parm
= cfun
->static_chain_decl
;
4316 rtx local
= gen_reg_rtx (Pmode
);
4318 set_decl_incoming_rtl (parm
, static_chain_incoming_rtx
, false);
4319 SET_DECL_RTL (parm
, local
);
4320 mark_reg_pointer (local
, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
4322 emit_move_insn (local
, static_chain_incoming_rtx
);
4325 /* If the function receives a non-local goto, then store the
4326 bits we need to restore the frame pointer. */
4327 if (cfun
->nonlocal_goto_save_area
)
4332 /* ??? We need to do this save early. Unfortunately here is
4333 before the frame variable gets declared. Help out... */
4334 tree var
= TREE_OPERAND (cfun
->nonlocal_goto_save_area
, 0);
4335 if (!DECL_RTL_SET_P (var
))
4338 t_save
= build4 (ARRAY_REF
, ptr_type_node
,
4339 cfun
->nonlocal_goto_save_area
,
4340 integer_zero_node
, NULL_TREE
, NULL_TREE
);
4341 r_save
= expand_expr (t_save
, NULL_RTX
, VOIDmode
, EXPAND_WRITE
);
4342 r_save
= convert_memory_address (Pmode
, r_save
);
4344 emit_move_insn (r_save
, targetm
.builtin_setjmp_frame_value ());
4345 update_nonlocal_goto_save_area ();
4348 /* The following was moved from init_function_start.
4349 The move is supposed to make sdb output more accurate. */
4350 /* Indicate the beginning of the function body,
4351 as opposed to parm setup. */
4352 emit_note (NOTE_INSN_FUNCTION_BEG
);
4354 gcc_assert (NOTE_P (get_last_insn ()));
4356 parm_birth_insn
= get_last_insn ();
4361 PROFILE_HOOK (current_function_funcdef_no
);
4365 /* After the display initializations is where the stack checking
4367 if(flag_stack_check
)
4368 stack_check_probe_note
= emit_note (NOTE_INSN_DELETED
);
4370 /* Make sure there is a line number after the function entry setup code. */
4371 force_next_line_note ();
4374 /* Undo the effects of init_dummy_function_start. */
4376 expand_dummy_function_end (void)
4378 gcc_assert (in_dummy_function
);
4380 /* End any sequences that failed to be closed due to syntax errors. */
4381 while (in_sequence_p ())
4384 /* Outside function body, can't compute type's actual size
4385 until next function's body starts. */
4387 free_after_parsing (cfun
);
4388 free_after_compilation (cfun
);
4390 in_dummy_function
= false;
4393 /* Call DOIT for each hard register used as a return value from
4394 the current function. */
4397 diddle_return_value (void (*doit
) (rtx
, void *), void *arg
)
4399 rtx outgoing
= crtl
->return_rtx
;
4404 if (REG_P (outgoing
))
4405 (*doit
) (outgoing
, arg
);
4406 else if (GET_CODE (outgoing
) == PARALLEL
)
4410 for (i
= 0; i
< XVECLEN (outgoing
, 0); i
++)
4412 rtx x
= XEXP (XVECEXP (outgoing
, 0, i
), 0);
4414 if (REG_P (x
) && REGNO (x
) < FIRST_PSEUDO_REGISTER
)
4421 do_clobber_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
4427 clobber_return_register (void)
4429 diddle_return_value (do_clobber_return_reg
, NULL
);
4431 /* In case we do use pseudo to return value, clobber it too. */
4432 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
4434 tree decl_result
= DECL_RESULT (current_function_decl
);
4435 rtx decl_rtl
= DECL_RTL (decl_result
);
4436 if (REG_P (decl_rtl
) && REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
)
4438 do_clobber_return_reg (decl_rtl
, NULL
);
4444 do_use_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
4450 use_return_register (void)
4452 diddle_return_value (do_use_return_reg
, NULL
);
4455 /* Possibly warn about unused parameters. */
4457 do_warn_unused_parameter (tree fn
)
4461 for (decl
= DECL_ARGUMENTS (fn
);
4462 decl
; decl
= TREE_CHAIN (decl
))
4463 if (!TREE_USED (decl
) && TREE_CODE (decl
) == PARM_DECL
4464 && DECL_NAME (decl
) && !DECL_ARTIFICIAL (decl
)
4465 && !TREE_NO_WARNING (decl
))
4466 warning (OPT_Wunused_parameter
, "unused parameter %q+D", decl
);
4469 static GTY(()) rtx initial_trampoline
;
4471 /* Generate RTL for the end of the current function. */
4474 expand_function_end (void)
4478 /* If arg_pointer_save_area was referenced only from a nested
4479 function, we will not have initialized it yet. Do that now. */
4480 if (arg_pointer_save_area
&& ! crtl
->arg_pointer_save_area_init
)
4481 get_arg_pointer_save_area ();
4483 /* If we are doing stack checking and this function makes calls,
4484 do a stack probe at the start of the function to ensure we have enough
4485 space for another stack frame. */
4486 if (flag_stack_check
&& ! STACK_CHECK_BUILTIN
)
4490 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
4494 probe_stack_range (STACK_CHECK_PROTECT
,
4495 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE
));
4498 emit_insn_before (seq
, stack_check_probe_note
);
4503 /* End any sequences that failed to be closed due to syntax errors. */
4504 while (in_sequence_p ())
4507 clear_pending_stack_adjust ();
4508 do_pending_stack_adjust ();
4510 /* Output a linenumber for the end of the function.
4511 SDB depends on this. */
4512 force_next_line_note ();
4513 set_curr_insn_source_location (input_location
);
4515 /* Before the return label (if any), clobber the return
4516 registers so that they are not propagated live to the rest of
4517 the function. This can only happen with functions that drop
4518 through; if there had been a return statement, there would
4519 have either been a return rtx, or a jump to the return label.
4521 We delay actual code generation after the current_function_value_rtx
4523 clobber_after
= get_last_insn ();
4525 /* Output the label for the actual return from the function. */
4526 emit_label (return_label
);
4528 if (USING_SJLJ_EXCEPTIONS
)
4530 /* Let except.c know where it should emit the call to unregister
4531 the function context for sjlj exceptions. */
4532 if (flag_exceptions
)
4533 sjlj_emit_function_exit_after (get_last_insn ());
4537 /* We want to ensure that instructions that may trap are not
4538 moved into the epilogue by scheduling, because we don't
4539 always emit unwind information for the epilogue. */
4540 if (flag_non_call_exceptions
)
4541 emit_insn (gen_blockage ());
4544 /* If this is an implementation of throw, do what's necessary to
4545 communicate between __builtin_eh_return and the epilogue. */
4546 expand_eh_return ();
4548 /* If scalar return value was computed in a pseudo-reg, or was a named
4549 return value that got dumped to the stack, copy that to the hard
4551 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
4553 tree decl_result
= DECL_RESULT (current_function_decl
);
4554 rtx decl_rtl
= DECL_RTL (decl_result
);
4556 if (REG_P (decl_rtl
)
4557 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
4558 : DECL_REGISTER (decl_result
))
4560 rtx real_decl_rtl
= crtl
->return_rtx
;
4562 /* This should be set in assign_parms. */
4563 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl
));
4565 /* If this is a BLKmode structure being returned in registers,
4566 then use the mode computed in expand_return. Note that if
4567 decl_rtl is memory, then its mode may have been changed,
4568 but that crtl->return_rtx has not. */
4569 if (GET_MODE (real_decl_rtl
) == BLKmode
)
4570 PUT_MODE (real_decl_rtl
, GET_MODE (decl_rtl
));
4572 /* If a non-BLKmode return value should be padded at the least
4573 significant end of the register, shift it left by the appropriate
4574 amount. BLKmode results are handled using the group load/store
4576 if (TYPE_MODE (TREE_TYPE (decl_result
)) != BLKmode
4577 && targetm
.calls
.return_in_msb (TREE_TYPE (decl_result
)))
4579 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl
),
4580 REGNO (real_decl_rtl
)),
4582 shift_return_value (GET_MODE (decl_rtl
), true, real_decl_rtl
);
4584 /* If a named return value dumped decl_return to memory, then
4585 we may need to re-do the PROMOTE_MODE signed/unsigned
4587 else if (GET_MODE (real_decl_rtl
) != GET_MODE (decl_rtl
))
4589 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (decl_result
));
4591 if (targetm
.calls
.promote_function_return (TREE_TYPE (current_function_decl
)))
4592 promote_mode (TREE_TYPE (decl_result
), GET_MODE (decl_rtl
),
4595 convert_move (real_decl_rtl
, decl_rtl
, unsignedp
);
4597 else if (GET_CODE (real_decl_rtl
) == PARALLEL
)
4599 /* If expand_function_start has created a PARALLEL for decl_rtl,
4600 move the result to the real return registers. Otherwise, do
4601 a group load from decl_rtl for a named return. */
4602 if (GET_CODE (decl_rtl
) == PARALLEL
)
4603 emit_group_move (real_decl_rtl
, decl_rtl
);
4605 emit_group_load (real_decl_rtl
, decl_rtl
,
4606 TREE_TYPE (decl_result
),
4607 int_size_in_bytes (TREE_TYPE (decl_result
)));
4609 /* In the case of complex integer modes smaller than a word, we'll
4610 need to generate some non-trivial bitfield insertions. Do that
4611 on a pseudo and not the hard register. */
4612 else if (GET_CODE (decl_rtl
) == CONCAT
4613 && GET_MODE_CLASS (GET_MODE (decl_rtl
)) == MODE_COMPLEX_INT
4614 && GET_MODE_BITSIZE (GET_MODE (decl_rtl
)) <= BITS_PER_WORD
)
4616 int old_generating_concat_p
;
4619 old_generating_concat_p
= generating_concat_p
;
4620 generating_concat_p
= 0;
4621 tmp
= gen_reg_rtx (GET_MODE (decl_rtl
));
4622 generating_concat_p
= old_generating_concat_p
;
4624 emit_move_insn (tmp
, decl_rtl
);
4625 emit_move_insn (real_decl_rtl
, tmp
);
4628 emit_move_insn (real_decl_rtl
, decl_rtl
);
4632 /* If returning a structure, arrange to return the address of the value
4633 in a place where debuggers expect to find it.
4635 If returning a structure PCC style,
4636 the caller also depends on this value.
4637 And cfun->returns_pcc_struct is not necessarily set. */
4638 if (cfun
->returns_struct
4639 || cfun
->returns_pcc_struct
)
4641 rtx value_address
= DECL_RTL (DECL_RESULT (current_function_decl
));
4642 tree type
= TREE_TYPE (DECL_RESULT (current_function_decl
));
4645 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl
)))
4646 type
= TREE_TYPE (type
);
4648 value_address
= XEXP (value_address
, 0);
4650 outgoing
= targetm
.calls
.function_value (build_pointer_type (type
),
4651 current_function_decl
, true);
4653 /* Mark this as a function return value so integrate will delete the
4654 assignment and USE below when inlining this function. */
4655 REG_FUNCTION_VALUE_P (outgoing
) = 1;
4657 /* The address may be ptr_mode and OUTGOING may be Pmode. */
4658 value_address
= convert_memory_address (GET_MODE (outgoing
),
4661 emit_move_insn (outgoing
, value_address
);
4663 /* Show return register used to hold result (in this case the address
4665 crtl
->return_rtx
= outgoing
;
4668 /* Emit the actual code to clobber return register. */
4673 clobber_return_register ();
4674 expand_naked_return ();
4678 emit_insn_after (seq
, clobber_after
);
4681 /* Output the label for the naked return from the function. */
4682 emit_label (naked_return_label
);
4684 /* @@@ This is a kludge. We want to ensure that instructions that
4685 may trap are not moved into the epilogue by scheduling, because
4686 we don't always emit unwind information for the epilogue. */
4687 if (! USING_SJLJ_EXCEPTIONS
&& flag_non_call_exceptions
)
4688 emit_insn (gen_blockage ());
4690 /* If stack protection is enabled for this function, check the guard. */
4691 if (crtl
->stack_protect_guard
)
4692 stack_protect_epilogue ();
4694 /* If we had calls to alloca, and this machine needs
4695 an accurate stack pointer to exit the function,
4696 insert some code to save and restore the stack pointer. */
4697 if (! EXIT_IGNORE_STACK
4698 && cfun
->calls_alloca
)
4702 emit_stack_save (SAVE_FUNCTION
, &tem
, parm_birth_insn
);
4703 emit_stack_restore (SAVE_FUNCTION
, tem
, NULL_RTX
);
4706 /* ??? This should no longer be necessary since stupid is no longer with
4707 us, but there are some parts of the compiler (eg reload_combine, and
4708 sh mach_dep_reorg) that still try and compute their own lifetime info
4709 instead of using the general framework. */
4710 use_return_register ();
4714 get_arg_pointer_save_area (void)
4716 rtx ret
= arg_pointer_save_area
;
4720 ret
= assign_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0);
4721 arg_pointer_save_area
= ret
;
4724 if (! crtl
->arg_pointer_save_area_init
)
4728 /* Save the arg pointer at the beginning of the function. The
4729 generated stack slot may not be a valid memory address, so we
4730 have to check it and fix it if necessary. */
4732 emit_move_insn (validize_mem (ret
),
4733 crtl
->args
.internal_arg_pointer
);
4737 push_topmost_sequence ();
4738 emit_insn_after (seq
, entry_of_function ());
4739 pop_topmost_sequence ();
4745 /* Extend a vector that records the INSN_UIDs of INSNS
4746 (a list of one or more insns). */
4749 record_insns (rtx insns
, VEC(int,heap
) **vecp
)
4753 for (tmp
= insns
; tmp
!= NULL_RTX
; tmp
= NEXT_INSN (tmp
))
4754 VEC_safe_push (int, heap
, *vecp
, INSN_UID (tmp
));
4757 /* Set the locator of the insn chain starting at INSN to LOC. */
4759 set_insn_locators (rtx insn
, int loc
)
4761 while (insn
!= NULL_RTX
)
4764 INSN_LOCATOR (insn
) = loc
;
4765 insn
= NEXT_INSN (insn
);
4769 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
4770 be running after reorg, SEQUENCE rtl is possible. */
4773 contains (const_rtx insn
, VEC(int,heap
) **vec
)
4777 if (NONJUMP_INSN_P (insn
)
4778 && GET_CODE (PATTERN (insn
)) == SEQUENCE
)
4781 for (i
= XVECLEN (PATTERN (insn
), 0) - 1; i
>= 0; i
--)
4782 for (j
= VEC_length (int, *vec
) - 1; j
>= 0; --j
)
4783 if (INSN_UID (XVECEXP (PATTERN (insn
), 0, i
))
4784 == VEC_index (int, *vec
, j
))
4790 for (j
= VEC_length (int, *vec
) - 1; j
>= 0; --j
)
4791 if (INSN_UID (insn
) == VEC_index (int, *vec
, j
))
4798 prologue_epilogue_contains (const_rtx insn
)
4800 if (contains (insn
, &prologue
))
4802 if (contains (insn
, &epilogue
))
4808 sibcall_epilogue_contains (const_rtx insn
)
4810 if (sibcall_epilogue
)
4811 return contains (insn
, &sibcall_epilogue
);
4816 /* Insert gen_return at the end of block BB. This also means updating
4817 block_for_insn appropriately. */
4820 emit_return_into_block (basic_block bb
)
4822 emit_jump_insn_after (gen_return (), BB_END (bb
));
4824 #endif /* HAVE_return */
4826 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
4827 this into place with notes indicating where the prologue ends and where
4828 the epilogue begins. Update the basic block information when possible. */
4831 thread_prologue_and_epilogue_insns (void)
4835 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
4838 #if defined (HAVE_epilogue) || defined(HAVE_return)
4839 rtx epilogue_end
= NULL_RTX
;
4843 #ifdef HAVE_prologue
4847 seq
= gen_prologue ();
4850 /* Insert an explicit USE for the frame pointer
4851 if the profiling is on and the frame pointer is required. */
4852 if (crtl
->profile
&& frame_pointer_needed
)
4853 emit_use (hard_frame_pointer_rtx
);
4855 /* Retain a map of the prologue insns. */
4856 record_insns (seq
, &prologue
);
4857 emit_note (NOTE_INSN_PROLOGUE_END
);
4859 #ifndef PROFILE_BEFORE_PROLOGUE
4860 /* Ensure that instructions are not moved into the prologue when
4861 profiling is on. The call to the profiling routine can be
4862 emitted within the live range of a call-clobbered register. */
4864 emit_insn (gen_blockage ());
4869 set_insn_locators (seq
, prologue_locator
);
4871 /* Can't deal with multiple successors of the entry block
4872 at the moment. Function should always have at least one
4874 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR
));
4876 insert_insn_on_edge (seq
, single_succ_edge (ENTRY_BLOCK_PTR
));
4881 /* If the exit block has no non-fake predecessors, we don't need
4883 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
4884 if ((e
->flags
& EDGE_FAKE
) == 0)
4890 if (optimize
&& HAVE_return
)
4892 /* If we're allowed to generate a simple return instruction,
4893 then by definition we don't need a full epilogue. Examine
4894 the block that falls through to EXIT. If it does not
4895 contain any code, examine its predecessors and try to
4896 emit (conditional) return instructions. */
4901 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
4902 if (e
->flags
& EDGE_FALLTHRU
)
4908 /* Verify that there are no active instructions in the last block. */
4909 label
= BB_END (last
);
4910 while (label
&& !LABEL_P (label
))
4912 if (active_insn_p (label
))
4914 label
= PREV_INSN (label
);
4917 if (BB_HEAD (last
) == label
&& LABEL_P (label
))
4921 for (ei2
= ei_start (last
->preds
); (e
= ei_safe_edge (ei2
)); )
4923 basic_block bb
= e
->src
;
4926 if (bb
== ENTRY_BLOCK_PTR
)
4933 if (!JUMP_P (jump
) || JUMP_LABEL (jump
) != label
)
4939 /* If we have an unconditional jump, we can replace that
4940 with a simple return instruction. */
4941 if (simplejump_p (jump
))
4943 emit_return_into_block (bb
);
4947 /* If we have a conditional jump, we can try to replace
4948 that with a conditional return instruction. */
4949 else if (condjump_p (jump
))
4951 if (! redirect_jump (jump
, 0, 0))
4957 /* If this block has only one successor, it both jumps
4958 and falls through to the fallthru block, so we can't
4960 if (single_succ_p (bb
))
4972 /* Fix up the CFG for the successful change we just made. */
4973 redirect_edge_succ (e
, EXIT_BLOCK_PTR
);
4976 /* Emit a return insn for the exit fallthru block. Whether
4977 this is still reachable will be determined later. */
4979 emit_barrier_after (BB_END (last
));
4980 emit_return_into_block (last
);
4981 epilogue_end
= BB_END (last
);
4982 single_succ_edge (last
)->flags
&= ~EDGE_FALLTHRU
;
4987 /* Find the edge that falls through to EXIT. Other edges may exist
4988 due to RETURN instructions, but those don't need epilogues.
4989 There really shouldn't be a mixture -- either all should have
4990 been converted or none, however... */
4992 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
4993 if (e
->flags
& EDGE_FALLTHRU
)
4998 #ifdef HAVE_epilogue
5002 epilogue_end
= emit_note (NOTE_INSN_EPILOGUE_BEG
);
5003 seq
= gen_epilogue ();
5004 emit_jump_insn (seq
);
5006 /* Retain a map of the epilogue insns. */
5007 record_insns (seq
, &epilogue
);
5008 set_insn_locators (seq
, epilogue_locator
);
5013 insert_insn_on_edge (seq
, e
);
5021 if (! next_active_insn (BB_END (e
->src
)))
5023 /* We have a fall-through edge to the exit block, the source is not
5024 at the end of the function, and there will be an assembler epilogue
5025 at the end of the function.
5026 We can't use force_nonfallthru here, because that would try to
5027 use return. Inserting a jump 'by hand' is extremely messy, so
5028 we take advantage of cfg_layout_finalize using
5029 fixup_fallthru_exit_predecessor. */
5030 cfg_layout_initialize (0);
5031 FOR_EACH_BB (cur_bb
)
5032 if (cur_bb
->index
>= NUM_FIXED_BLOCKS
5033 && cur_bb
->next_bb
->index
>= NUM_FIXED_BLOCKS
)
5034 cur_bb
->aux
= cur_bb
->next_bb
;
5035 cfg_layout_finalize ();
5041 commit_edge_insertions ();
5043 /* The epilogue insns we inserted may cause the exit edge to no longer
5045 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5047 if (((e
->flags
& EDGE_FALLTHRU
) != 0)
5048 && returnjump_p (BB_END (e
->src
)))
5049 e
->flags
&= ~EDGE_FALLTHRU
;
5053 #ifdef HAVE_sibcall_epilogue
5054 /* Emit sibling epilogues before any sibling call sites. */
5055 for (ei
= ei_start (EXIT_BLOCK_PTR
->preds
); (e
= ei_safe_edge (ei
)); )
5057 basic_block bb
= e
->src
;
5058 rtx insn
= BB_END (bb
);
5061 || ! SIBLING_CALL_P (insn
))
5068 emit_insn (gen_sibcall_epilogue ());
5072 /* Retain a map of the epilogue insns. Used in life analysis to
5073 avoid getting rid of sibcall epilogue insns. Do this before we
5074 actually emit the sequence. */
5075 record_insns (seq
, &sibcall_epilogue
);
5076 set_insn_locators (seq
, epilogue_locator
);
5078 emit_insn_before (seq
, insn
);
5083 #ifdef HAVE_epilogue
5088 /* Similarly, move any line notes that appear after the epilogue.
5089 There is no need, however, to be quite so anal about the existence
5090 of such a note. Also possibly move
5091 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
5093 for (insn
= epilogue_end
; insn
; insn
= next
)
5095 next
= NEXT_INSN (insn
);
5097 && (NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
))
5098 reorder_insns (insn
, insn
, PREV_INSN (epilogue_end
));
5103 /* Threading the prologue and epilogue changes the artificial refs
5104 in the entry and exit blocks. */
5105 epilogue_completed
= 1;
5106 df_update_entry_exit_and_calls ();
5109 /* Reposition the prologue-end and epilogue-begin notes after instruction
5110 scheduling and delayed branch scheduling. */
5113 reposition_prologue_and_epilogue_notes (void)
5115 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
5116 rtx insn
, last
, note
;
5119 if ((len
= VEC_length (int, prologue
)) > 0)
5123 /* Scan from the beginning until we reach the last prologue insn.
5124 We apparently can't depend on basic_block_{head,end} after
5126 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
5130 if (NOTE_KIND (insn
) == NOTE_INSN_PROLOGUE_END
)
5133 else if (contains (insn
, &prologue
))
5143 /* Find the prologue-end note if we haven't already, and
5144 move it to just after the last prologue insn. */
5147 for (note
= last
; (note
= NEXT_INSN (note
));)
5149 && NOTE_KIND (note
) == NOTE_INSN_PROLOGUE_END
)
5153 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
5155 last
= NEXT_INSN (last
);
5156 reorder_insns (note
, note
, last
);
5160 if ((len
= VEC_length (int, epilogue
)) > 0)
5164 /* Scan from the end until we reach the first epilogue insn.
5165 We apparently can't depend on basic_block_{head,end} after
5167 for (insn
= get_last_insn (); insn
; insn
= PREV_INSN (insn
))
5171 if (NOTE_KIND (insn
) == NOTE_INSN_EPILOGUE_BEG
)
5174 else if (contains (insn
, &epilogue
))
5184 /* Find the epilogue-begin note if we haven't already, and
5185 move it to just before the first epilogue insn. */
5188 for (note
= insn
; (note
= PREV_INSN (note
));)
5190 && NOTE_KIND (note
) == NOTE_INSN_EPILOGUE_BEG
)
5194 if (PREV_INSN (last
) != note
)
5195 reorder_insns (note
, note
, PREV_INSN (last
));
5198 #endif /* HAVE_prologue or HAVE_epilogue */
5201 /* Returns the name of the current function. */
5203 current_function_name (void)
5205 return lang_hooks
.decl_printable_name (cfun
->decl
, 2);
5208 /* Returns the raw (mangled) name of the current function. */
5210 current_function_assembler_name (void)
5212 return IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (cfun
->decl
));
5217 rest_of_handle_check_leaf_regs (void)
5219 #ifdef LEAF_REGISTERS
5220 current_function_uses_only_leaf_regs
5221 = optimize
> 0 && only_leaf_regs_used () && leaf_function_p ();
5226 /* Insert a TYPE into the used types hash table of CFUN. */
5228 used_types_insert_helper (tree type
, struct function
*func
)
5230 if (type
!= NULL
&& func
!= NULL
)
5234 if (func
->used_types_hash
== NULL
)
5235 func
->used_types_hash
= htab_create_ggc (37, htab_hash_pointer
,
5236 htab_eq_pointer
, NULL
);
5237 slot
= htab_find_slot (func
->used_types_hash
, type
, INSERT
);
5243 /* Given a type, insert it into the used hash table in cfun. */
5245 used_types_insert (tree t
)
5247 while (POINTER_TYPE_P (t
) || TREE_CODE (t
) == ARRAY_TYPE
)
5249 t
= TYPE_MAIN_VARIANT (t
);
5250 if (debug_info_level
> DINFO_LEVEL_NONE
)
5251 used_types_insert_helper (t
, cfun
);
5254 struct rtl_opt_pass pass_leaf_regs
=
5260 rest_of_handle_check_leaf_regs
, /* execute */
5263 0, /* static_pass_number */
5265 0, /* properties_required */
5266 0, /* properties_provided */
5267 0, /* properties_destroyed */
5268 0, /* todo_flags_start */
5269 0 /* todo_flags_finish */
5274 rest_of_handle_thread_prologue_and_epilogue (void)
5277 cleanup_cfg (CLEANUP_EXPENSIVE
);
5278 /* On some machines, the prologue and epilogue code, or parts thereof,
5279 can be represented as RTL. Doing so lets us schedule insns between
5280 it and the rest of the code and also allows delayed branch
5281 scheduling to operate in the epilogue. */
5283 thread_prologue_and_epilogue_insns ();
5287 struct rtl_opt_pass pass_thread_prologue_and_epilogue
=
5291 "pro_and_epilogue", /* name */
5293 rest_of_handle_thread_prologue_and_epilogue
, /* execute */
5296 0, /* static_pass_number */
5297 TV_THREAD_PROLOGUE_AND_EPILOGUE
, /* tv_id */
5298 0, /* properties_required */
5299 0, /* properties_provided */
5300 0, /* properties_destroyed */
5301 TODO_verify_flow
, /* todo_flags_start */
5304 TODO_df_finish
| TODO_verify_rtl_sharing
|
5305 TODO_ggc_collect
/* todo_flags_finish */
5310 /* This mini-pass fixes fall-out from SSA in asm statements that have
5311 in-out constraints. Say you start with
5314 asm ("": "+mr" (inout));
5317 which is transformed very early to use explicit output and match operands:
5320 asm ("": "=mr" (inout) : "0" (inout));
5323 Or, after SSA and copyprop,
5325 asm ("": "=mr" (inout_2) : "0" (inout_1));
5328 Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
5329 they represent two separate values, so they will get different pseudo
5330 registers during expansion. Then, since the two operands need to match
5331 per the constraints, but use different pseudo registers, reload can
5332 only register a reload for these operands. But reloads can only be
5333 satisfied by hardregs, not by memory, so we need a register for this
5334 reload, just because we are presented with non-matching operands.
5335 So, even though we allow memory for this operand, no memory can be
5336 used for it, just because the two operands don't match. This can
5337 cause reload failures on register-starved targets.
5339 So it's a symptom of reload not being able to use memory for reloads
5340 or, alternatively it's also a symptom of both operands not coming into
5341 reload as matching (in which case the pseudo could go to memory just
5342 fine, as the alternative allows it, and no reload would be necessary).
5343 We fix the latter problem here, by transforming
5345 asm ("": "=mr" (inout_2) : "0" (inout_1));
5350 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
5353 match_asm_constraints_1 (rtx insn
, rtx
*p_sets
, int noutputs
)
5356 bool changed
= false;
5357 rtx op
= SET_SRC (p_sets
[0]);
5358 int ninputs
= ASM_OPERANDS_INPUT_LENGTH (op
);
5359 rtvec inputs
= ASM_OPERANDS_INPUT_VEC (op
);
5360 bool *output_matched
= XALLOCAVEC (bool, noutputs
);
5362 memset (output_matched
, 0, noutputs
* sizeof (bool));
5363 for (i
= 0; i
< ninputs
; i
++)
5365 rtx input
, output
, insns
;
5366 const char *constraint
= ASM_OPERANDS_INPUT_CONSTRAINT (op
, i
);
5370 match
= strtoul (constraint
, &end
, 10);
5371 if (end
== constraint
)
5374 gcc_assert (match
< noutputs
);
5375 output
= SET_DEST (p_sets
[match
]);
5376 input
= RTVEC_ELT (inputs
, i
);
5377 /* Only do the transformation for pseudos. */
5378 if (! REG_P (output
)
5379 || rtx_equal_p (output
, input
)
5380 || (GET_MODE (input
) != VOIDmode
5381 && GET_MODE (input
) != GET_MODE (output
)))
5384 /* We can't do anything if the output is also used as input,
5385 as we're going to overwrite it. */
5386 for (j
= 0; j
< ninputs
; j
++)
5387 if (reg_overlap_mentioned_p (output
, RTVEC_ELT (inputs
, j
)))
5392 /* Avoid changing the same input several times. For
5393 asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
5394 only change in once (to out1), rather than changing it
5395 first to out1 and afterwards to out2. */
5398 for (j
= 0; j
< noutputs
; j
++)
5399 if (output_matched
[j
] && input
== SET_DEST (p_sets
[j
]))
5404 output_matched
[match
] = true;
5407 emit_move_insn (output
, input
);
5408 insns
= get_insns ();
5410 emit_insn_before (insns
, insn
);
5412 /* Now replace all mentions of the input with output. We can't
5413 just replace the occurrence in inputs[i], as the register might
5414 also be used in some other input (or even in an address of an
5415 output), which would mean possibly increasing the number of
5416 inputs by one (namely 'output' in addition), which might pose
5417 a too complicated problem for reload to solve. E.g. this situation:
5419 asm ("" : "=r" (output), "=m" (input) : "0" (input))
5421 Here 'input' is used in two occurrences as input (once for the
5422 input operand, once for the address in the second output operand).
5423 If we would replace only the occurrence of the input operand (to
5424 make the matching) we would be left with this:
5427 asm ("" : "=r" (output), "=m" (input) : "0" (output))
5429 Now we suddenly have two different input values (containing the same
5430 value, but different pseudos) where we formerly had only one.
5431 With more complicated asms this might lead to reload failures
5432 which wouldn't have happen without this pass. So, iterate over
5433 all operands and replace all occurrences of the register used. */
5434 for (j
= 0; j
< noutputs
; j
++)
5435 if (!rtx_equal_p (SET_DEST (p_sets
[j
]), input
)
5436 && reg_overlap_mentioned_p (input
, SET_DEST (p_sets
[j
])))
5437 SET_DEST (p_sets
[j
]) = replace_rtx (SET_DEST (p_sets
[j
]),
5439 for (j
= 0; j
< ninputs
; j
++)
5440 if (reg_overlap_mentioned_p (input
, RTVEC_ELT (inputs
, j
)))
5441 RTVEC_ELT (inputs
, j
) = replace_rtx (RTVEC_ELT (inputs
, j
),
5448 df_insn_rescan (insn
);
5452 rest_of_match_asm_constraints (void)
5455 rtx insn
, pat
, *p_sets
;
5458 if (!crtl
->has_asm_statement
)
5461 df_set_flags (DF_DEFER_INSN_RESCAN
);
5464 FOR_BB_INSNS (bb
, insn
)
5469 pat
= PATTERN (insn
);
5470 if (GET_CODE (pat
) == PARALLEL
)
5471 p_sets
= &XVECEXP (pat
, 0, 0), noutputs
= XVECLEN (pat
, 0);
5472 else if (GET_CODE (pat
) == SET
)
5473 p_sets
= &PATTERN (insn
), noutputs
= 1;
5477 if (GET_CODE (*p_sets
) == SET
5478 && GET_CODE (SET_SRC (*p_sets
)) == ASM_OPERANDS
)
5479 match_asm_constraints_1 (insn
, p_sets
, noutputs
);
5483 return TODO_df_finish
;
5486 struct rtl_opt_pass pass_match_asm_constraints
=
5490 "asmcons", /* name */
5492 rest_of_match_asm_constraints
, /* execute */
5495 0, /* static_pass_number */
5497 0, /* properties_required */
5498 0, /* properties_provided */
5499 0, /* properties_destroyed */
5500 0, /* todo_flags_start */
5501 TODO_dump_func
/* todo_flags_finish */
5506 #include "gt-function.h"