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"
62 #include "tree-gimple.h"
63 #include "tree-pass.h"
69 /* So we can assign to cfun in this file. */
72 #ifndef LOCAL_ALIGNMENT
73 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
76 #ifndef STACK_ALIGNMENT_NEEDED
77 #define STACK_ALIGNMENT_NEEDED 1
80 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
82 /* Some systems use __main in a way incompatible with its use in gcc, in these
83 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
84 give the same symbol without quotes for an alternative entry point. You
85 must define both, or neither. */
87 #define NAME__MAIN "__main"
90 /* Round a value to the lowest integer less than it that is a multiple of
91 the required alignment. Avoid using division in case the value is
92 negative. Assume the alignment is a power of two. */
93 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
95 /* Similar, but round to the next highest integer that meets the
97 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
99 /* Nonzero if function being compiled doesn't contain any calls
100 (ignoring the prologue and epilogue). This is set prior to
101 local register allocation and is valid for the remaining
103 int current_function_is_leaf
;
105 /* Nonzero if function being compiled doesn't modify the stack pointer
106 (ignoring the prologue and epilogue). This is only valid after
107 pass_stack_ptr_mod has run. */
108 int current_function_sp_is_unchanging
;
110 /* Nonzero if the function being compiled is a leaf function which only
111 uses leaf registers. This is valid after reload (specifically after
112 sched2) and is useful only if the port defines LEAF_REGISTERS. */
113 int current_function_uses_only_leaf_regs
;
115 /* Nonzero once virtual register instantiation has been done.
116 assign_stack_local uses frame_pointer_rtx when this is nonzero.
117 calls.c:emit_library_call_value_1 uses it to set up
118 post-instantiation libcalls. */
119 int virtuals_instantiated
;
121 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
122 static GTY(()) int funcdef_no
;
124 /* These variables hold pointers to functions to create and destroy
125 target specific, per-function data structures. */
126 struct machine_function
* (*init_machine_status
) (void);
128 /* The currently compiled function. */
129 struct function
*cfun
= 0;
131 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
132 static VEC(int,heap
) *prologue
;
133 static VEC(int,heap
) *epilogue
;
135 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
137 static VEC(int,heap
) *sibcall_epilogue
;
139 /* In order to evaluate some expressions, such as function calls returning
140 structures in memory, we need to temporarily allocate stack locations.
141 We record each allocated temporary in the following structure.
143 Associated with each temporary slot is a nesting level. When we pop up
144 one level, all temporaries associated with the previous level are freed.
145 Normally, all temporaries are freed after the execution of the statement
146 in which they were created. However, if we are inside a ({...}) grouping,
147 the result may be in a temporary and hence must be preserved. If the
148 result could be in a temporary, we preserve it if we can determine which
149 one it is in. If we cannot determine which temporary may contain the
150 result, all temporaries are preserved. A temporary is preserved by
151 pretending it was allocated at the previous nesting level.
153 Automatic variables are also assigned temporary slots, at the nesting
154 level where they are defined. They are marked a "kept" so that
155 free_temp_slots will not free them. */
157 struct temp_slot
GTY(())
159 /* Points to next temporary slot. */
160 struct temp_slot
*next
;
161 /* Points to previous temporary slot. */
162 struct temp_slot
*prev
;
164 /* The rtx to used to reference the slot. */
166 /* The rtx used to represent the address if not the address of the
167 slot above. May be an EXPR_LIST if multiple addresses exist. */
169 /* The alignment (in bits) of the slot. */
171 /* The size, in units, of the slot. */
173 /* The type of the object in the slot, or zero if it doesn't correspond
174 to a type. We use this to determine whether a slot can be reused.
175 It can be reused if objects of the type of the new slot will always
176 conflict with objects of the type of the old slot. */
178 /* Nonzero if this temporary is currently in use. */
180 /* Nonzero if this temporary has its address taken. */
182 /* Nesting level at which this slot is being used. */
184 /* Nonzero if this should survive a call to free_temp_slots. */
186 /* The offset of the slot from the frame_pointer, including extra space
187 for alignment. This info is for combine_temp_slots. */
188 HOST_WIDE_INT base_offset
;
189 /* The size of the slot, including extra space for alignment. This
190 info is for combine_temp_slots. */
191 HOST_WIDE_INT full_size
;
194 /* Forward declarations. */
196 static struct temp_slot
*find_temp_slot_from_address (rtx
);
197 static void pad_to_arg_alignment (struct args_size
*, int, struct args_size
*);
198 static void pad_below (struct args_size
*, enum machine_mode
, tree
);
199 static void reorder_blocks_1 (rtx
, tree
, VEC(tree
,heap
) **);
200 static int all_blocks (tree
, tree
*);
201 static tree
*get_block_vector (tree
, int *);
202 extern tree
debug_find_var_in_block_tree (tree
, tree
);
203 /* We always define `record_insns' even if it's not used so that we
204 can always export `prologue_epilogue_contains'. */
205 static void record_insns (rtx
, VEC(int,heap
) **) ATTRIBUTE_UNUSED
;
206 static int contains (const_rtx
, VEC(int,heap
) **);
208 static void emit_return_into_block (basic_block
);
210 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
211 static rtx
keep_stack_depressed (rtx
);
213 static void prepare_function_start (void);
214 static void do_clobber_return_reg (rtx
, void *);
215 static void do_use_return_reg (rtx
, void *);
216 static void set_insn_locators (rtx
, int) ATTRIBUTE_UNUSED
;
218 /* Pointer to chain of `struct function' for containing functions. */
219 struct function
*outer_function_chain
;
221 /* Given a function decl for a containing function,
222 return the `struct function' for it. */
225 find_function_data (tree decl
)
229 for (p
= outer_function_chain
; p
; p
= p
->outer
)
236 /* Save the current context for compilation of a nested function.
237 This is called from language-specific code. */
240 push_function_context (void)
243 allocate_struct_function (NULL
, false);
245 cfun
->outer
= outer_function_chain
;
246 outer_function_chain
= cfun
;
250 /* Restore the last saved context, at the end of a nested function.
251 This function is called from language-specific code. */
254 pop_function_context (void)
256 struct function
*p
= outer_function_chain
;
259 outer_function_chain
= p
->outer
;
260 current_function_decl
= p
->decl
;
262 /* Reset variables that have known state during rtx generation. */
263 virtuals_instantiated
= 0;
264 generating_concat_p
= 1;
267 /* Clear out all parts of the state in F that can safely be discarded
268 after the function has been parsed, but not compiled, to let
269 garbage collection reclaim the memory. */
272 free_after_parsing (struct function
*f
)
277 /* Clear out all parts of the state in F that can safely be discarded
278 after the function has been compiled, to let garbage collection
279 reclaim the memory. */
282 free_after_compilation (struct function
*f
)
284 VEC_free (int, heap
, prologue
);
285 VEC_free (int, heap
, epilogue
);
286 VEC_free (int, heap
, sibcall_epilogue
);
287 if (rtl
.emit
.regno_pointer_align
)
288 free (rtl
.emit
.regno_pointer_align
);
290 memset (&rtl
, 0, sizeof (rtl
));
295 f
->arg_offset_rtx
= NULL
;
296 f
->return_rtx
= NULL
;
297 f
->internal_arg_pointer
= NULL
;
298 f
->epilogue_delay_list
= NULL
;
301 /* Return size needed for stack frame based on slots so far allocated.
302 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
303 the caller may have to do that. */
306 get_frame_size (void)
308 if (FRAME_GROWS_DOWNWARD
)
309 return -frame_offset
;
314 /* Issue an error message and return TRUE if frame OFFSET overflows in
315 the signed target pointer arithmetics for function FUNC. Otherwise
319 frame_offset_overflow (HOST_WIDE_INT offset
, tree func
)
321 unsigned HOST_WIDE_INT size
= FRAME_GROWS_DOWNWARD
? -offset
: offset
;
323 if (size
> ((unsigned HOST_WIDE_INT
) 1 << (GET_MODE_BITSIZE (Pmode
) - 1))
324 /* Leave room for the fixed part of the frame. */
325 - 64 * UNITS_PER_WORD
)
327 error ("%Jtotal size of local objects too large", func
);
334 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
335 with machine mode MODE.
337 ALIGN controls the amount of alignment for the address of the slot:
338 0 means according to MODE,
339 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
340 -2 means use BITS_PER_UNIT,
341 positive specifies alignment boundary in bits.
343 We do not round to stack_boundary here. */
346 assign_stack_local (enum machine_mode mode
, HOST_WIDE_INT size
, int align
)
349 int bigend_correction
= 0;
350 unsigned int alignment
;
351 int frame_off
, frame_alignment
, frame_phase
;
358 alignment
= BIGGEST_ALIGNMENT
;
360 alignment
= GET_MODE_ALIGNMENT (mode
);
362 /* Allow the target to (possibly) increase the alignment of this
364 type
= lang_hooks
.types
.type_for_mode (mode
, 0);
366 alignment
= LOCAL_ALIGNMENT (type
, alignment
);
368 alignment
/= BITS_PER_UNIT
;
370 else if (align
== -1)
372 alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
373 size
= CEIL_ROUND (size
, alignment
);
375 else if (align
== -2)
376 alignment
= 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
378 alignment
= align
/ BITS_PER_UNIT
;
380 if (FRAME_GROWS_DOWNWARD
)
381 frame_offset
-= size
;
383 /* Ignore alignment we can't do with expected alignment of the boundary. */
384 if (alignment
* BITS_PER_UNIT
> PREFERRED_STACK_BOUNDARY
)
385 alignment
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
387 if (cfun
->stack_alignment_needed
< alignment
* BITS_PER_UNIT
)
388 cfun
->stack_alignment_needed
= alignment
* BITS_PER_UNIT
;
390 /* Calculate how many bytes the start of local variables is off from
392 frame_alignment
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
393 frame_off
= STARTING_FRAME_OFFSET
% frame_alignment
;
394 frame_phase
= frame_off
? frame_alignment
- frame_off
: 0;
396 /* Round the frame offset to the specified alignment. The default is
397 to always honor requests to align the stack but a port may choose to
398 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
399 if (STACK_ALIGNMENT_NEEDED
403 /* We must be careful here, since FRAME_OFFSET might be negative and
404 division with a negative dividend isn't as well defined as we might
405 like. So we instead assume that ALIGNMENT is a power of two and
406 use logical operations which are unambiguous. */
407 if (FRAME_GROWS_DOWNWARD
)
409 = (FLOOR_ROUND (frame_offset
- frame_phase
,
410 (unsigned HOST_WIDE_INT
) alignment
)
414 = (CEIL_ROUND (frame_offset
- frame_phase
,
415 (unsigned HOST_WIDE_INT
) alignment
)
419 /* On a big-endian machine, if we are allocating more space than we will use,
420 use the least significant bytes of those that are allocated. */
421 if (BYTES_BIG_ENDIAN
&& mode
!= BLKmode
&& GET_MODE_SIZE (mode
) < size
)
422 bigend_correction
= size
- GET_MODE_SIZE (mode
);
424 /* If we have already instantiated virtual registers, return the actual
425 address relative to the frame pointer. */
426 if (virtuals_instantiated
)
427 addr
= plus_constant (frame_pointer_rtx
,
429 (frame_offset
+ bigend_correction
430 + STARTING_FRAME_OFFSET
, Pmode
));
432 addr
= plus_constant (virtual_stack_vars_rtx
,
434 (frame_offset
+ bigend_correction
,
437 if (!FRAME_GROWS_DOWNWARD
)
438 frame_offset
+= size
;
440 x
= gen_rtx_MEM (mode
, addr
);
441 MEM_NOTRAP_P (x
) = 1;
444 = gen_rtx_EXPR_LIST (VOIDmode
, x
, stack_slot_list
);
446 if (frame_offset_overflow (frame_offset
, current_function_decl
))
452 /* Removes temporary slot TEMP from LIST. */
455 cut_slot_from_list (struct temp_slot
*temp
, struct temp_slot
**list
)
458 temp
->next
->prev
= temp
->prev
;
460 temp
->prev
->next
= temp
->next
;
464 temp
->prev
= temp
->next
= NULL
;
467 /* Inserts temporary slot TEMP to LIST. */
470 insert_slot_to_list (struct temp_slot
*temp
, struct temp_slot
**list
)
474 (*list
)->prev
= temp
;
479 /* Returns the list of used temp slots at LEVEL. */
481 static struct temp_slot
**
482 temp_slots_at_level (int level
)
484 if (level
>= (int) VEC_length (temp_slot_p
, used_temp_slots
))
485 VEC_safe_grow_cleared (temp_slot_p
, gc
, used_temp_slots
, level
+ 1);
487 return &(VEC_address (temp_slot_p
, used_temp_slots
)[level
]);
490 /* Returns the maximal temporary slot level. */
493 max_slot_level (void)
495 if (!used_temp_slots
)
498 return VEC_length (temp_slot_p
, used_temp_slots
) - 1;
501 /* Moves temporary slot TEMP to LEVEL. */
504 move_slot_to_level (struct temp_slot
*temp
, int level
)
506 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
507 insert_slot_to_list (temp
, temp_slots_at_level (level
));
511 /* Make temporary slot TEMP available. */
514 make_slot_available (struct temp_slot
*temp
)
516 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
517 insert_slot_to_list (temp
, &avail_temp_slots
);
522 /* Allocate a temporary stack slot and record it for possible later
525 MODE is the machine mode to be given to the returned rtx.
527 SIZE is the size in units of the space required. We do no rounding here
528 since assign_stack_local will do any required rounding.
530 KEEP is 1 if this slot is to be retained after a call to
531 free_temp_slots. Automatic variables for a block are allocated
532 with this flag. KEEP values of 2 or 3 were needed respectively
533 for variables whose lifetime is controlled by CLEANUP_POINT_EXPRs
534 or for SAVE_EXPRs, but they are now unused.
536 TYPE is the type that will be used for the stack slot. */
539 assign_stack_temp_for_type (enum machine_mode mode
, HOST_WIDE_INT size
,
543 struct temp_slot
*p
, *best_p
= 0, *selected
= NULL
, **pp
;
546 /* If SIZE is -1 it means that somebody tried to allocate a temporary
547 of a variable size. */
548 gcc_assert (size
!= -1);
550 /* These are now unused. */
551 gcc_assert (keep
<= 1);
554 align
= BIGGEST_ALIGNMENT
;
556 align
= GET_MODE_ALIGNMENT (mode
);
559 type
= lang_hooks
.types
.type_for_mode (mode
, 0);
562 align
= LOCAL_ALIGNMENT (type
, align
);
564 /* Try to find an available, already-allocated temporary of the proper
565 mode which meets the size and alignment requirements. Choose the
566 smallest one with the closest alignment.
568 If assign_stack_temp is called outside of the tree->rtl expansion,
569 we cannot reuse the stack slots (that may still refer to
570 VIRTUAL_STACK_VARS_REGNUM). */
571 if (!virtuals_instantiated
)
573 for (p
= avail_temp_slots
; p
; p
= p
->next
)
575 if (p
->align
>= align
&& p
->size
>= size
576 && GET_MODE (p
->slot
) == mode
577 && objects_must_conflict_p (p
->type
, type
)
578 && (best_p
== 0 || best_p
->size
> p
->size
579 || (best_p
->size
== p
->size
&& best_p
->align
> p
->align
)))
581 if (p
->align
== align
&& p
->size
== size
)
584 cut_slot_from_list (selected
, &avail_temp_slots
);
593 /* Make our best, if any, the one to use. */
597 cut_slot_from_list (selected
, &avail_temp_slots
);
599 /* If there are enough aligned bytes left over, make them into a new
600 temp_slot so that the extra bytes don't get wasted. Do this only
601 for BLKmode slots, so that we can be sure of the alignment. */
602 if (GET_MODE (best_p
->slot
) == BLKmode
)
604 int alignment
= best_p
->align
/ BITS_PER_UNIT
;
605 HOST_WIDE_INT rounded_size
= CEIL_ROUND (size
, alignment
);
607 if (best_p
->size
- rounded_size
>= alignment
)
609 p
= ggc_alloc (sizeof (struct temp_slot
));
610 p
->in_use
= p
->addr_taken
= 0;
611 p
->size
= best_p
->size
- rounded_size
;
612 p
->base_offset
= best_p
->base_offset
+ rounded_size
;
613 p
->full_size
= best_p
->full_size
- rounded_size
;
614 p
->slot
= adjust_address_nv (best_p
->slot
, BLKmode
, rounded_size
);
615 p
->align
= best_p
->align
;
617 p
->type
= best_p
->type
;
618 insert_slot_to_list (p
, &avail_temp_slots
);
620 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, p
->slot
,
623 best_p
->size
= rounded_size
;
624 best_p
->full_size
= rounded_size
;
629 /* If we still didn't find one, make a new temporary. */
632 HOST_WIDE_INT frame_offset_old
= frame_offset
;
634 p
= ggc_alloc (sizeof (struct temp_slot
));
636 /* We are passing an explicit alignment request to assign_stack_local.
637 One side effect of that is assign_stack_local will not round SIZE
638 to ensure the frame offset remains suitably aligned.
640 So for requests which depended on the rounding of SIZE, we go ahead
641 and round it now. We also make sure ALIGNMENT is at least
642 BIGGEST_ALIGNMENT. */
643 gcc_assert (mode
!= BLKmode
|| align
== BIGGEST_ALIGNMENT
);
644 p
->slot
= assign_stack_local (mode
,
646 ? CEIL_ROUND (size
, (int) align
/ BITS_PER_UNIT
)
652 /* The following slot size computation is necessary because we don't
653 know the actual size of the temporary slot until assign_stack_local
654 has performed all the frame alignment and size rounding for the
655 requested temporary. Note that extra space added for alignment
656 can be either above or below this stack slot depending on which
657 way the frame grows. We include the extra space if and only if it
658 is above this slot. */
659 if (FRAME_GROWS_DOWNWARD
)
660 p
->size
= frame_offset_old
- frame_offset
;
664 /* Now define the fields used by combine_temp_slots. */
665 if (FRAME_GROWS_DOWNWARD
)
667 p
->base_offset
= frame_offset
;
668 p
->full_size
= frame_offset_old
- frame_offset
;
672 p
->base_offset
= frame_offset_old
;
673 p
->full_size
= frame_offset
- frame_offset_old
;
684 p
->level
= temp_slot_level
;
687 pp
= temp_slots_at_level (p
->level
);
688 insert_slot_to_list (p
, pp
);
690 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
691 slot
= gen_rtx_MEM (mode
, XEXP (p
->slot
, 0));
692 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, slot
, stack_slot_list
);
694 /* If we know the alias set for the memory that will be used, use
695 it. If there's no TYPE, then we don't know anything about the
696 alias set for the memory. */
697 set_mem_alias_set (slot
, type
? get_alias_set (type
) : 0);
698 set_mem_align (slot
, align
);
700 /* If a type is specified, set the relevant flags. */
703 MEM_VOLATILE_P (slot
) = TYPE_VOLATILE (type
);
704 MEM_SET_IN_STRUCT_P (slot
, (AGGREGATE_TYPE_P (type
)
705 || TREE_CODE (type
) == COMPLEX_TYPE
));
707 MEM_NOTRAP_P (slot
) = 1;
712 /* Allocate a temporary stack slot and record it for possible later
713 reuse. First three arguments are same as in preceding function. */
716 assign_stack_temp (enum machine_mode mode
, HOST_WIDE_INT size
, int keep
)
718 return assign_stack_temp_for_type (mode
, size
, keep
, NULL_TREE
);
721 /* Assign a temporary.
722 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
723 and so that should be used in error messages. In either case, we
724 allocate of the given type.
725 KEEP is as for assign_stack_temp.
726 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
727 it is 0 if a register is OK.
728 DONT_PROMOTE is 1 if we should not promote values in register
732 assign_temp (tree type_or_decl
, int keep
, int memory_required
,
733 int dont_promote ATTRIBUTE_UNUSED
)
736 enum machine_mode mode
;
741 if (DECL_P (type_or_decl
))
742 decl
= type_or_decl
, type
= TREE_TYPE (decl
);
744 decl
= NULL
, type
= type_or_decl
;
746 mode
= TYPE_MODE (type
);
748 unsignedp
= TYPE_UNSIGNED (type
);
751 if (mode
== BLKmode
|| memory_required
)
753 HOST_WIDE_INT size
= int_size_in_bytes (type
);
756 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
757 problems with allocating the stack space. */
761 /* Unfortunately, we don't yet know how to allocate variable-sized
762 temporaries. However, sometimes we can find a fixed upper limit on
763 the size, so try that instead. */
765 size
= max_int_size_in_bytes (type
);
767 /* The size of the temporary may be too large to fit into an integer. */
768 /* ??? Not sure this should happen except for user silliness, so limit
769 this to things that aren't compiler-generated temporaries. The
770 rest of the time we'll die in assign_stack_temp_for_type. */
771 if (decl
&& size
== -1
772 && TREE_CODE (TYPE_SIZE_UNIT (type
)) == INTEGER_CST
)
774 error ("size of variable %q+D is too large", decl
);
778 tmp
= assign_stack_temp_for_type (mode
, size
, keep
, type
);
784 mode
= promote_mode (type
, mode
, &unsignedp
, 0);
787 return gen_reg_rtx (mode
);
790 /* Combine temporary stack slots which are adjacent on the stack.
792 This allows for better use of already allocated stack space. This is only
793 done for BLKmode slots because we can be sure that we won't have alignment
794 problems in this case. */
797 combine_temp_slots (void)
799 struct temp_slot
*p
, *q
, *next
, *next_q
;
802 /* We can't combine slots, because the information about which slot
803 is in which alias set will be lost. */
804 if (flag_strict_aliasing
)
807 /* If there are a lot of temp slots, don't do anything unless
808 high levels of optimization. */
809 if (! flag_expensive_optimizations
)
810 for (p
= avail_temp_slots
, num_slots
= 0; p
; p
= p
->next
, num_slots
++)
811 if (num_slots
> 100 || (num_slots
> 10 && optimize
== 0))
814 for (p
= avail_temp_slots
; p
; p
= next
)
820 if (GET_MODE (p
->slot
) != BLKmode
)
823 for (q
= p
->next
; q
; q
= next_q
)
829 if (GET_MODE (q
->slot
) != BLKmode
)
832 if (p
->base_offset
+ p
->full_size
== q
->base_offset
)
834 /* Q comes after P; combine Q into P. */
836 p
->full_size
+= q
->full_size
;
839 else if (q
->base_offset
+ q
->full_size
== p
->base_offset
)
841 /* P comes after Q; combine P into Q. */
843 q
->full_size
+= p
->full_size
;
848 cut_slot_from_list (q
, &avail_temp_slots
);
851 /* Either delete P or advance past it. */
853 cut_slot_from_list (p
, &avail_temp_slots
);
857 /* Find the temp slot corresponding to the object at address X. */
859 static struct temp_slot
*
860 find_temp_slot_from_address (rtx x
)
866 for (i
= max_slot_level (); i
>= 0; i
--)
867 for (p
= *temp_slots_at_level (i
); p
; p
= p
->next
)
869 if (XEXP (p
->slot
, 0) == x
871 || (GET_CODE (x
) == PLUS
872 && XEXP (x
, 0) == virtual_stack_vars_rtx
873 && GET_CODE (XEXP (x
, 1)) == CONST_INT
874 && INTVAL (XEXP (x
, 1)) >= p
->base_offset
875 && INTVAL (XEXP (x
, 1)) < p
->base_offset
+ p
->full_size
))
878 else if (p
->address
!= 0 && GET_CODE (p
->address
) == EXPR_LIST
)
879 for (next
= p
->address
; next
; next
= XEXP (next
, 1))
880 if (XEXP (next
, 0) == x
)
884 /* If we have a sum involving a register, see if it points to a temp
886 if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 0))
887 && (p
= find_temp_slot_from_address (XEXP (x
, 0))) != 0)
889 else if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 1))
890 && (p
= find_temp_slot_from_address (XEXP (x
, 1))) != 0)
896 /* Indicate that NEW is an alternate way of referring to the temp slot
897 that previously was known by OLD. */
900 update_temp_slot_address (rtx old
, rtx
new)
904 if (rtx_equal_p (old
, new))
907 p
= find_temp_slot_from_address (old
);
909 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
910 is a register, see if one operand of the PLUS is a temporary
911 location. If so, NEW points into it. Otherwise, if both OLD and
912 NEW are a PLUS and if there is a register in common between them.
913 If so, try a recursive call on those values. */
916 if (GET_CODE (old
) != PLUS
)
921 update_temp_slot_address (XEXP (old
, 0), new);
922 update_temp_slot_address (XEXP (old
, 1), new);
925 else if (GET_CODE (new) != PLUS
)
928 if (rtx_equal_p (XEXP (old
, 0), XEXP (new, 0)))
929 update_temp_slot_address (XEXP (old
, 1), XEXP (new, 1));
930 else if (rtx_equal_p (XEXP (old
, 1), XEXP (new, 0)))
931 update_temp_slot_address (XEXP (old
, 0), XEXP (new, 1));
932 else if (rtx_equal_p (XEXP (old
, 0), XEXP (new, 1)))
933 update_temp_slot_address (XEXP (old
, 1), XEXP (new, 0));
934 else if (rtx_equal_p (XEXP (old
, 1), XEXP (new, 1)))
935 update_temp_slot_address (XEXP (old
, 0), XEXP (new, 0));
940 /* Otherwise add an alias for the temp's address. */
941 else if (p
->address
== 0)
945 if (GET_CODE (p
->address
) != EXPR_LIST
)
946 p
->address
= gen_rtx_EXPR_LIST (VOIDmode
, p
->address
, NULL_RTX
);
948 p
->address
= gen_rtx_EXPR_LIST (VOIDmode
, new, p
->address
);
952 /* If X could be a reference to a temporary slot, mark the fact that its
953 address was taken. */
956 mark_temp_addr_taken (rtx x
)
963 /* If X is not in memory or is at a constant address, it cannot be in
965 if (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0)))
968 p
= find_temp_slot_from_address (XEXP (x
, 0));
973 /* If X could be a reference to a temporary slot, mark that slot as
974 belonging to the to one level higher than the current level. If X
975 matched one of our slots, just mark that one. Otherwise, we can't
976 easily predict which it is, so upgrade all of them. Kept slots
979 This is called when an ({...}) construct occurs and a statement
980 returns a value in memory. */
983 preserve_temp_slots (rtx x
)
985 struct temp_slot
*p
= 0, *next
;
987 /* If there is no result, we still might have some objects whose address
988 were taken, so we need to make sure they stay around. */
991 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
996 move_slot_to_level (p
, temp_slot_level
- 1);
1002 /* If X is a register that is being used as a pointer, see if we have
1003 a temporary slot we know it points to. To be consistent with
1004 the code below, we really should preserve all non-kept slots
1005 if we can't find a match, but that seems to be much too costly. */
1006 if (REG_P (x
) && REG_POINTER (x
))
1007 p
= find_temp_slot_from_address (x
);
1009 /* If X is not in memory or is at a constant address, it cannot be in
1010 a temporary slot, but it can contain something whose address was
1012 if (p
== 0 && (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0))))
1014 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1019 move_slot_to_level (p
, temp_slot_level
- 1);
1025 /* First see if we can find a match. */
1027 p
= find_temp_slot_from_address (XEXP (x
, 0));
1031 /* Move everything at our level whose address was taken to our new
1032 level in case we used its address. */
1033 struct temp_slot
*q
;
1035 if (p
->level
== temp_slot_level
)
1037 for (q
= *temp_slots_at_level (temp_slot_level
); q
; q
= next
)
1041 if (p
!= q
&& q
->addr_taken
)
1042 move_slot_to_level (q
, temp_slot_level
- 1);
1045 move_slot_to_level (p
, temp_slot_level
- 1);
1051 /* Otherwise, preserve all non-kept slots at this level. */
1052 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1057 move_slot_to_level (p
, temp_slot_level
- 1);
1061 /* Free all temporaries used so far. This is normally called at the
1062 end of generating code for a statement. */
1065 free_temp_slots (void)
1067 struct temp_slot
*p
, *next
;
1069 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1074 make_slot_available (p
);
1077 combine_temp_slots ();
1080 /* Push deeper into the nesting level for stack temporaries. */
1083 push_temp_slots (void)
1088 /* Pop a temporary nesting level. All slots in use in the current level
1092 pop_temp_slots (void)
1094 struct temp_slot
*p
, *next
;
1096 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1099 make_slot_available (p
);
1102 combine_temp_slots ();
1107 /* Initialize temporary slots. */
1110 init_temp_slots (void)
1112 /* We have not allocated any temporaries yet. */
1113 avail_temp_slots
= 0;
1114 used_temp_slots
= 0;
1115 temp_slot_level
= 0;
1118 /* These routines are responsible for converting virtual register references
1119 to the actual hard register references once RTL generation is complete.
1121 The following four variables are used for communication between the
1122 routines. They contain the offsets of the virtual registers from their
1123 respective hard registers. */
1125 static int in_arg_offset
;
1126 static int var_offset
;
1127 static int dynamic_offset
;
1128 static int out_arg_offset
;
1129 static int cfa_offset
;
1131 /* In most machines, the stack pointer register is equivalent to the bottom
1134 #ifndef STACK_POINTER_OFFSET
1135 #define STACK_POINTER_OFFSET 0
1138 /* If not defined, pick an appropriate default for the offset of dynamically
1139 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1140 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1142 #ifndef STACK_DYNAMIC_OFFSET
1144 /* The bottom of the stack points to the actual arguments. If
1145 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1146 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1147 stack space for register parameters is not pushed by the caller, but
1148 rather part of the fixed stack areas and hence not included in
1149 `current_function_outgoing_args_size'. Nevertheless, we must allow
1150 for it when allocating stack dynamic objects. */
1152 #if defined(REG_PARM_STACK_SPACE)
1153 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1154 ((ACCUMULATE_OUTGOING_ARGS \
1155 ? (current_function_outgoing_args_size \
1156 + (OUTGOING_REG_PARM_STACK_SPACE ? 0 : REG_PARM_STACK_SPACE (FNDECL))) \
1157 : 0) + (STACK_POINTER_OFFSET))
1159 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1160 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
1161 + (STACK_POINTER_OFFSET))
1166 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1167 is a virtual register, return the equivalent hard register and set the
1168 offset indirectly through the pointer. Otherwise, return 0. */
1171 instantiate_new_reg (rtx x
, HOST_WIDE_INT
*poffset
)
1174 HOST_WIDE_INT offset
;
1176 if (x
== virtual_incoming_args_rtx
)
1177 new = arg_pointer_rtx
, offset
= in_arg_offset
;
1178 else if (x
== virtual_stack_vars_rtx
)
1179 new = frame_pointer_rtx
, offset
= var_offset
;
1180 else if (x
== virtual_stack_dynamic_rtx
)
1181 new = stack_pointer_rtx
, offset
= dynamic_offset
;
1182 else if (x
== virtual_outgoing_args_rtx
)
1183 new = stack_pointer_rtx
, offset
= out_arg_offset
;
1184 else if (x
== virtual_cfa_rtx
)
1186 #ifdef FRAME_POINTER_CFA_OFFSET
1187 new = frame_pointer_rtx
;
1189 new = arg_pointer_rtx
;
1191 offset
= cfa_offset
;
1200 /* A subroutine of instantiate_virtual_regs, called via for_each_rtx.
1201 Instantiate any virtual registers present inside of *LOC. The expression
1202 is simplified, as much as possible, but is not to be considered "valid"
1203 in any sense implied by the target. If any change is made, set CHANGED
1207 instantiate_virtual_regs_in_rtx (rtx
*loc
, void *data
)
1209 HOST_WIDE_INT offset
;
1210 bool *changed
= (bool *) data
;
1217 switch (GET_CODE (x
))
1220 new = instantiate_new_reg (x
, &offset
);
1223 *loc
= plus_constant (new, offset
);
1230 new = instantiate_new_reg (XEXP (x
, 0), &offset
);
1233 new = plus_constant (new, offset
);
1234 *loc
= simplify_gen_binary (PLUS
, GET_MODE (x
), new, XEXP (x
, 1));
1240 /* FIXME -- from old code */
1241 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1242 we can commute the PLUS and SUBREG because pointers into the
1243 frame are well-behaved. */
1253 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1254 matches the predicate for insn CODE operand OPERAND. */
1257 safe_insn_predicate (int code
, int operand
, rtx x
)
1259 const struct insn_operand_data
*op_data
;
1264 op_data
= &insn_data
[code
].operand
[operand
];
1265 if (op_data
->predicate
== NULL
)
1268 return op_data
->predicate (x
, op_data
->mode
);
1271 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1272 registers present inside of insn. The result will be a valid insn. */
1275 instantiate_virtual_regs_in_insn (rtx insn
)
1277 HOST_WIDE_INT offset
;
1279 bool any_change
= false;
1280 rtx set
, new, x
, seq
;
1282 /* There are some special cases to be handled first. */
1283 set
= single_set (insn
);
1286 /* We're allowed to assign to a virtual register. This is interpreted
1287 to mean that the underlying register gets assigned the inverse
1288 transformation. This is used, for example, in the handling of
1290 new = instantiate_new_reg (SET_DEST (set
), &offset
);
1295 for_each_rtx (&SET_SRC (set
), instantiate_virtual_regs_in_rtx
, NULL
);
1296 x
= simplify_gen_binary (PLUS
, GET_MODE (new), SET_SRC (set
),
1298 x
= force_operand (x
, new);
1300 emit_move_insn (new, x
);
1305 emit_insn_before (seq
, insn
);
1310 /* Handle a straight copy from a virtual register by generating a
1311 new add insn. The difference between this and falling through
1312 to the generic case is avoiding a new pseudo and eliminating a
1313 move insn in the initial rtl stream. */
1314 new = instantiate_new_reg (SET_SRC (set
), &offset
);
1315 if (new && offset
!= 0
1316 && REG_P (SET_DEST (set
))
1317 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1321 x
= expand_simple_binop (GET_MODE (SET_DEST (set
)), PLUS
,
1322 new, GEN_INT (offset
), SET_DEST (set
),
1323 1, OPTAB_LIB_WIDEN
);
1324 if (x
!= SET_DEST (set
))
1325 emit_move_insn (SET_DEST (set
), x
);
1330 emit_insn_before (seq
, insn
);
1335 extract_insn (insn
);
1336 insn_code
= INSN_CODE (insn
);
1338 /* Handle a plus involving a virtual register by determining if the
1339 operands remain valid if they're modified in place. */
1340 if (GET_CODE (SET_SRC (set
)) == PLUS
1341 && recog_data
.n_operands
>= 3
1342 && recog_data
.operand_loc
[1] == &XEXP (SET_SRC (set
), 0)
1343 && recog_data
.operand_loc
[2] == &XEXP (SET_SRC (set
), 1)
1344 && GET_CODE (recog_data
.operand
[2]) == CONST_INT
1345 && (new = instantiate_new_reg (recog_data
.operand
[1], &offset
)))
1347 offset
+= INTVAL (recog_data
.operand
[2]);
1349 /* If the sum is zero, then replace with a plain move. */
1351 && REG_P (SET_DEST (set
))
1352 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1355 emit_move_insn (SET_DEST (set
), new);
1359 emit_insn_before (seq
, insn
);
1364 x
= gen_int_mode (offset
, recog_data
.operand_mode
[2]);
1366 /* Using validate_change and apply_change_group here leaves
1367 recog_data in an invalid state. Since we know exactly what
1368 we want to check, do those two by hand. */
1369 if (safe_insn_predicate (insn_code
, 1, new)
1370 && safe_insn_predicate (insn_code
, 2, x
))
1372 *recog_data
.operand_loc
[1] = recog_data
.operand
[1] = new;
1373 *recog_data
.operand_loc
[2] = recog_data
.operand
[2] = x
;
1376 /* Fall through into the regular operand fixup loop in
1377 order to take care of operands other than 1 and 2. */
1383 extract_insn (insn
);
1384 insn_code
= INSN_CODE (insn
);
1387 /* In the general case, we expect virtual registers to appear only in
1388 operands, and then only as either bare registers or inside memories. */
1389 for (i
= 0; i
< recog_data
.n_operands
; ++i
)
1391 x
= recog_data
.operand
[i
];
1392 switch (GET_CODE (x
))
1396 rtx addr
= XEXP (x
, 0);
1397 bool changed
= false;
1399 for_each_rtx (&addr
, instantiate_virtual_regs_in_rtx
, &changed
);
1404 x
= replace_equiv_address (x
, addr
);
1405 /* It may happen that the address with the virtual reg
1406 was valid (e.g. based on the virtual stack reg, which might
1407 be acceptable to the predicates with all offsets), whereas
1408 the address now isn't anymore, for instance when the address
1409 is still offsetted, but the base reg isn't virtual-stack-reg
1410 anymore. Below we would do a force_reg on the whole operand,
1411 but this insn might actually only accept memory. Hence,
1412 before doing that last resort, try to reload the address into
1413 a register, so this operand stays a MEM. */
1414 if (!safe_insn_predicate (insn_code
, i
, x
))
1416 addr
= force_reg (GET_MODE (addr
), addr
);
1417 x
= replace_equiv_address (x
, addr
);
1422 emit_insn_before (seq
, insn
);
1427 new = instantiate_new_reg (x
, &offset
);
1436 /* Careful, special mode predicates may have stuff in
1437 insn_data[insn_code].operand[i].mode that isn't useful
1438 to us for computing a new value. */
1439 /* ??? Recognize address_operand and/or "p" constraints
1440 to see if (plus new offset) is a valid before we put
1441 this through expand_simple_binop. */
1442 x
= expand_simple_binop (GET_MODE (x
), PLUS
, new,
1443 GEN_INT (offset
), NULL_RTX
,
1444 1, OPTAB_LIB_WIDEN
);
1447 emit_insn_before (seq
, insn
);
1452 new = instantiate_new_reg (SUBREG_REG (x
), &offset
);
1458 new = expand_simple_binop (GET_MODE (new), PLUS
, new,
1459 GEN_INT (offset
), NULL_RTX
,
1460 1, OPTAB_LIB_WIDEN
);
1463 emit_insn_before (seq
, insn
);
1465 x
= simplify_gen_subreg (recog_data
.operand_mode
[i
], new,
1466 GET_MODE (new), SUBREG_BYTE (x
));
1473 /* At this point, X contains the new value for the operand.
1474 Validate the new value vs the insn predicate. Note that
1475 asm insns will have insn_code -1 here. */
1476 if (!safe_insn_predicate (insn_code
, i
, x
))
1479 x
= force_reg (insn_data
[insn_code
].operand
[i
].mode
, x
);
1483 emit_insn_before (seq
, insn
);
1486 *recog_data
.operand_loc
[i
] = recog_data
.operand
[i
] = x
;
1492 /* Propagate operand changes into the duplicates. */
1493 for (i
= 0; i
< recog_data
.n_dups
; ++i
)
1494 *recog_data
.dup_loc
[i
]
1495 = copy_rtx (recog_data
.operand
[(unsigned)recog_data
.dup_num
[i
]]);
1497 /* Force re-recognition of the instruction for validation. */
1498 INSN_CODE (insn
) = -1;
1501 if (asm_noperands (PATTERN (insn
)) >= 0)
1503 if (!check_asm_operands (PATTERN (insn
)))
1505 error_for_asm (insn
, "impossible constraint in %<asm%>");
1511 if (recog_memoized (insn
) < 0)
1512 fatal_insn_not_found (insn
);
1516 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1517 do any instantiation required. */
1520 instantiate_decl_rtl (rtx x
)
1527 /* If this is a CONCAT, recurse for the pieces. */
1528 if (GET_CODE (x
) == CONCAT
)
1530 instantiate_decl_rtl (XEXP (x
, 0));
1531 instantiate_decl_rtl (XEXP (x
, 1));
1535 /* If this is not a MEM, no need to do anything. Similarly if the
1536 address is a constant or a register that is not a virtual register. */
1541 if (CONSTANT_P (addr
)
1543 && (REGNO (addr
) < FIRST_VIRTUAL_REGISTER
1544 || REGNO (addr
) > LAST_VIRTUAL_REGISTER
)))
1547 for_each_rtx (&XEXP (x
, 0), instantiate_virtual_regs_in_rtx
, NULL
);
1550 /* Helper for instantiate_decls called via walk_tree: Process all decls
1551 in the given DECL_VALUE_EXPR. */
1554 instantiate_expr (tree
*tp
, int *walk_subtrees
, void *data ATTRIBUTE_UNUSED
)
1557 if (! EXPR_P (t
) && ! GIMPLE_STMT_P (t
))
1560 if (DECL_P (t
) && DECL_RTL_SET_P (t
))
1561 instantiate_decl_rtl (DECL_RTL (t
));
1566 /* Subroutine of instantiate_decls: Process all decls in the given
1567 BLOCK node and all its subblocks. */
1570 instantiate_decls_1 (tree let
)
1574 for (t
= BLOCK_VARS (let
); t
; t
= TREE_CHAIN (t
))
1576 if (DECL_RTL_SET_P (t
))
1577 instantiate_decl_rtl (DECL_RTL (t
));
1578 if (TREE_CODE (t
) == VAR_DECL
&& DECL_HAS_VALUE_EXPR_P (t
))
1580 tree v
= DECL_VALUE_EXPR (t
);
1581 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1585 /* Process all subblocks. */
1586 for (t
= BLOCK_SUBBLOCKS (let
); t
; t
= BLOCK_CHAIN (t
))
1587 instantiate_decls_1 (t
);
1590 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1591 all virtual registers in their DECL_RTL's. */
1594 instantiate_decls (tree fndecl
)
1598 /* Process all parameters of the function. */
1599 for (decl
= DECL_ARGUMENTS (fndecl
); decl
; decl
= TREE_CHAIN (decl
))
1601 instantiate_decl_rtl (DECL_RTL (decl
));
1602 instantiate_decl_rtl (DECL_INCOMING_RTL (decl
));
1603 if (DECL_HAS_VALUE_EXPR_P (decl
))
1605 tree v
= DECL_VALUE_EXPR (decl
);
1606 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1610 /* Now process all variables defined in the function or its subblocks. */
1611 instantiate_decls_1 (DECL_INITIAL (fndecl
));
1614 /* Pass through the INSNS of function FNDECL and convert virtual register
1615 references to hard register references. */
1618 instantiate_virtual_regs (void)
1622 /* Compute the offsets to use for this function. */
1623 in_arg_offset
= FIRST_PARM_OFFSET (current_function_decl
);
1624 var_offset
= STARTING_FRAME_OFFSET
;
1625 dynamic_offset
= STACK_DYNAMIC_OFFSET (current_function_decl
);
1626 out_arg_offset
= STACK_POINTER_OFFSET
;
1627 #ifdef FRAME_POINTER_CFA_OFFSET
1628 cfa_offset
= FRAME_POINTER_CFA_OFFSET (current_function_decl
);
1630 cfa_offset
= ARG_POINTER_CFA_OFFSET (current_function_decl
);
1633 /* Initialize recognition, indicating that volatile is OK. */
1636 /* Scan through all the insns, instantiating every virtual register still
1638 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
1641 /* These patterns in the instruction stream can never be recognized.
1642 Fortunately, they shouldn't contain virtual registers either. */
1643 if (GET_CODE (PATTERN (insn
)) == USE
1644 || GET_CODE (PATTERN (insn
)) == CLOBBER
1645 || GET_CODE (PATTERN (insn
)) == ADDR_VEC
1646 || GET_CODE (PATTERN (insn
)) == ADDR_DIFF_VEC
1647 || GET_CODE (PATTERN (insn
)) == ASM_INPUT
)
1650 instantiate_virtual_regs_in_insn (insn
);
1652 if (INSN_DELETED_P (insn
))
1655 for_each_rtx (®_NOTES (insn
), instantiate_virtual_regs_in_rtx
, NULL
);
1657 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1658 if (GET_CODE (insn
) == CALL_INSN
)
1659 for_each_rtx (&CALL_INSN_FUNCTION_USAGE (insn
),
1660 instantiate_virtual_regs_in_rtx
, NULL
);
1663 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1664 instantiate_decls (current_function_decl
);
1666 targetm
.instantiate_decls ();
1668 /* Indicate that, from now on, assign_stack_local should use
1669 frame_pointer_rtx. */
1670 virtuals_instantiated
= 1;
1674 struct rtl_opt_pass pass_instantiate_virtual_regs
=
1680 instantiate_virtual_regs
, /* execute */
1683 0, /* static_pass_number */
1685 0, /* properties_required */
1686 0, /* properties_provided */
1687 0, /* properties_destroyed */
1688 0, /* todo_flags_start */
1689 TODO_dump_func
/* todo_flags_finish */
1694 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
1695 This means a type for which function calls must pass an address to the
1696 function or get an address back from the function.
1697 EXP may be a type node or an expression (whose type is tested). */
1700 aggregate_value_p (const_tree exp
, const_tree fntype
)
1702 int i
, regno
, nregs
;
1705 const_tree type
= (TYPE_P (exp
)) ? exp
: TREE_TYPE (exp
);
1707 /* DECL node associated with FNTYPE when relevant, which we might need to
1708 check for by-invisible-reference returns, typically for CALL_EXPR input
1710 const_tree fndecl
= NULL_TREE
;
1713 switch (TREE_CODE (fntype
))
1716 fndecl
= get_callee_fndecl (fntype
);
1717 fntype
= fndecl
? TREE_TYPE (fndecl
) : 0;
1721 fntype
= TREE_TYPE (fndecl
);
1726 case IDENTIFIER_NODE
:
1730 /* We don't expect other rtl types here. */
1734 if (TREE_CODE (type
) == VOID_TYPE
)
1737 /* If the front end has decided that this needs to be passed by
1738 reference, do so. */
1739 if ((TREE_CODE (exp
) == PARM_DECL
|| TREE_CODE (exp
) == RESULT_DECL
)
1740 && DECL_BY_REFERENCE (exp
))
1743 /* If the EXPression is a CALL_EXPR, honor DECL_BY_REFERENCE set on the
1744 called function RESULT_DECL, meaning the function returns in memory by
1745 invisible reference. This check lets front-ends not set TREE_ADDRESSABLE
1746 on the function type, which used to be the way to request such a return
1747 mechanism but might now be causing troubles at gimplification time if
1748 temporaries with the function type need to be created. */
1749 if (TREE_CODE (exp
) == CALL_EXPR
&& fndecl
&& DECL_RESULT (fndecl
)
1750 && DECL_BY_REFERENCE (DECL_RESULT (fndecl
)))
1753 if (targetm
.calls
.return_in_memory (type
, fntype
))
1755 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
1756 and thus can't be returned in registers. */
1757 if (TREE_ADDRESSABLE (type
))
1759 if (flag_pcc_struct_return
&& AGGREGATE_TYPE_P (type
))
1761 /* Make sure we have suitable call-clobbered regs to return
1762 the value in; if not, we must return it in memory. */
1763 reg
= hard_function_value (type
, 0, fntype
, 0);
1765 /* If we have something other than a REG (e.g. a PARALLEL), then assume
1770 regno
= REGNO (reg
);
1771 nregs
= hard_regno_nregs
[regno
][TYPE_MODE (type
)];
1772 for (i
= 0; i
< nregs
; i
++)
1773 if (! call_used_regs
[regno
+ i
])
1778 /* Return true if we should assign DECL a pseudo register; false if it
1779 should live on the local stack. */
1782 use_register_for_decl (const_tree decl
)
1784 /* Honor volatile. */
1785 if (TREE_SIDE_EFFECTS (decl
))
1788 /* Honor addressability. */
1789 if (TREE_ADDRESSABLE (decl
))
1792 /* Only register-like things go in registers. */
1793 if (DECL_MODE (decl
) == BLKmode
)
1796 /* If -ffloat-store specified, don't put explicit float variables
1798 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
1799 propagates values across these stores, and it probably shouldn't. */
1800 if (flag_float_store
&& FLOAT_TYPE_P (TREE_TYPE (decl
)))
1803 /* If we're not interested in tracking debugging information for
1804 this decl, then we can certainly put it in a register. */
1805 if (DECL_IGNORED_P (decl
))
1808 return (optimize
|| DECL_REGISTER (decl
));
1811 /* Return true if TYPE should be passed by invisible reference. */
1814 pass_by_reference (CUMULATIVE_ARGS
*ca
, enum machine_mode mode
,
1815 tree type
, bool named_arg
)
1819 /* If this type contains non-trivial constructors, then it is
1820 forbidden for the middle-end to create any new copies. */
1821 if (TREE_ADDRESSABLE (type
))
1824 /* GCC post 3.4 passes *all* variable sized types by reference. */
1825 if (!TYPE_SIZE (type
) || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
1829 return targetm
.calls
.pass_by_reference (ca
, mode
, type
, named_arg
);
1832 /* Return true if TYPE, which is passed by reference, should be callee
1833 copied instead of caller copied. */
1836 reference_callee_copied (CUMULATIVE_ARGS
*ca
, enum machine_mode mode
,
1837 tree type
, bool named_arg
)
1839 if (type
&& TREE_ADDRESSABLE (type
))
1841 return targetm
.calls
.callee_copies (ca
, mode
, type
, named_arg
);
1844 /* Structures to communicate between the subroutines of assign_parms.
1845 The first holds data persistent across all parameters, the second
1846 is cleared out for each parameter. */
1848 struct assign_parm_data_all
1850 CUMULATIVE_ARGS args_so_far
;
1851 struct args_size stack_args_size
;
1852 tree function_result_decl
;
1854 rtx first_conversion_insn
;
1855 rtx last_conversion_insn
;
1856 HOST_WIDE_INT pretend_args_size
;
1857 HOST_WIDE_INT extra_pretend_bytes
;
1858 int reg_parm_stack_space
;
1861 struct assign_parm_data_one
1867 enum machine_mode nominal_mode
;
1868 enum machine_mode passed_mode
;
1869 enum machine_mode promoted_mode
;
1870 struct locate_and_pad_arg_data locate
;
1872 BOOL_BITFIELD named_arg
: 1;
1873 BOOL_BITFIELD passed_pointer
: 1;
1874 BOOL_BITFIELD on_stack
: 1;
1875 BOOL_BITFIELD loaded_in_reg
: 1;
1878 /* A subroutine of assign_parms. Initialize ALL. */
1881 assign_parms_initialize_all (struct assign_parm_data_all
*all
)
1885 memset (all
, 0, sizeof (*all
));
1887 fntype
= TREE_TYPE (current_function_decl
);
1889 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
1890 INIT_CUMULATIVE_INCOMING_ARGS (all
->args_so_far
, fntype
, NULL_RTX
);
1892 INIT_CUMULATIVE_ARGS (all
->args_so_far
, fntype
, NULL_RTX
,
1893 current_function_decl
, -1);
1896 #ifdef REG_PARM_STACK_SPACE
1897 all
->reg_parm_stack_space
= REG_PARM_STACK_SPACE (current_function_decl
);
1901 /* If ARGS contains entries with complex types, split the entry into two
1902 entries of the component type. Return a new list of substitutions are
1903 needed, else the old list. */
1906 split_complex_args (tree args
)
1910 /* Before allocating memory, check for the common case of no complex. */
1911 for (p
= args
; p
; p
= TREE_CHAIN (p
))
1913 tree type
= TREE_TYPE (p
);
1914 if (TREE_CODE (type
) == COMPLEX_TYPE
1915 && targetm
.calls
.split_complex_arg (type
))
1921 args
= copy_list (args
);
1923 for (p
= args
; p
; p
= TREE_CHAIN (p
))
1925 tree type
= TREE_TYPE (p
);
1926 if (TREE_CODE (type
) == COMPLEX_TYPE
1927 && targetm
.calls
.split_complex_arg (type
))
1930 tree subtype
= TREE_TYPE (type
);
1931 bool addressable
= TREE_ADDRESSABLE (p
);
1933 /* Rewrite the PARM_DECL's type with its component. */
1934 TREE_TYPE (p
) = subtype
;
1935 DECL_ARG_TYPE (p
) = TREE_TYPE (DECL_ARG_TYPE (p
));
1936 DECL_MODE (p
) = VOIDmode
;
1937 DECL_SIZE (p
) = NULL
;
1938 DECL_SIZE_UNIT (p
) = NULL
;
1939 /* If this arg must go in memory, put it in a pseudo here.
1940 We can't allow it to go in memory as per normal parms,
1941 because the usual place might not have the imag part
1942 adjacent to the real part. */
1943 DECL_ARTIFICIAL (p
) = addressable
;
1944 DECL_IGNORED_P (p
) = addressable
;
1945 TREE_ADDRESSABLE (p
) = 0;
1948 /* Build a second synthetic decl. */
1949 decl
= build_decl (PARM_DECL
, NULL_TREE
, subtype
);
1950 DECL_ARG_TYPE (decl
) = DECL_ARG_TYPE (p
);
1951 DECL_ARTIFICIAL (decl
) = addressable
;
1952 DECL_IGNORED_P (decl
) = addressable
;
1953 layout_decl (decl
, 0);
1955 /* Splice it in; skip the new decl. */
1956 TREE_CHAIN (decl
) = TREE_CHAIN (p
);
1957 TREE_CHAIN (p
) = decl
;
1965 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
1966 the hidden struct return argument, and (abi willing) complex args.
1967 Return the new parameter list. */
1970 assign_parms_augmented_arg_list (struct assign_parm_data_all
*all
)
1972 tree fndecl
= current_function_decl
;
1973 tree fntype
= TREE_TYPE (fndecl
);
1974 tree fnargs
= DECL_ARGUMENTS (fndecl
);
1976 /* If struct value address is treated as the first argument, make it so. */
1977 if (aggregate_value_p (DECL_RESULT (fndecl
), fndecl
)
1978 && ! current_function_returns_pcc_struct
1979 && targetm
.calls
.struct_value_rtx (TREE_TYPE (fndecl
), 1) == 0)
1981 tree type
= build_pointer_type (TREE_TYPE (fntype
));
1984 decl
= build_decl (PARM_DECL
, NULL_TREE
, type
);
1985 DECL_ARG_TYPE (decl
) = type
;
1986 DECL_ARTIFICIAL (decl
) = 1;
1987 DECL_IGNORED_P (decl
) = 1;
1989 TREE_CHAIN (decl
) = fnargs
;
1991 all
->function_result_decl
= decl
;
1994 all
->orig_fnargs
= fnargs
;
1996 /* If the target wants to split complex arguments into scalars, do so. */
1997 if (targetm
.calls
.split_complex_arg
)
1998 fnargs
= split_complex_args (fnargs
);
2003 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2004 data for the parameter. Incorporate ABI specifics such as pass-by-
2005 reference and type promotion. */
2008 assign_parm_find_data_types (struct assign_parm_data_all
*all
, tree parm
,
2009 struct assign_parm_data_one
*data
)
2011 tree nominal_type
, passed_type
;
2012 enum machine_mode nominal_mode
, passed_mode
, promoted_mode
;
2014 memset (data
, 0, sizeof (*data
));
2016 /* NAMED_ARG is a mis-nomer. We really mean 'non-varadic'. */
2017 if (!current_function_stdarg
)
2018 data
->named_arg
= 1; /* No varadic parms. */
2019 else if (TREE_CHAIN (parm
))
2020 data
->named_arg
= 1; /* Not the last non-varadic parm. */
2021 else if (targetm
.calls
.strict_argument_naming (&all
->args_so_far
))
2022 data
->named_arg
= 1; /* Only varadic ones are unnamed. */
2024 data
->named_arg
= 0; /* Treat as varadic. */
2026 nominal_type
= TREE_TYPE (parm
);
2027 passed_type
= DECL_ARG_TYPE (parm
);
2029 /* Look out for errors propagating this far. Also, if the parameter's
2030 type is void then its value doesn't matter. */
2031 if (TREE_TYPE (parm
) == error_mark_node
2032 /* This can happen after weird syntax errors
2033 or if an enum type is defined among the parms. */
2034 || TREE_CODE (parm
) != PARM_DECL
2035 || passed_type
== NULL
2036 || VOID_TYPE_P (nominal_type
))
2038 nominal_type
= passed_type
= void_type_node
;
2039 nominal_mode
= passed_mode
= promoted_mode
= VOIDmode
;
2043 /* Find mode of arg as it is passed, and mode of arg as it should be
2044 during execution of this function. */
2045 passed_mode
= TYPE_MODE (passed_type
);
2046 nominal_mode
= TYPE_MODE (nominal_type
);
2048 /* If the parm is to be passed as a transparent union, use the type of
2049 the first field for the tests below. We have already verified that
2050 the modes are the same. */
2051 if (TREE_CODE (passed_type
) == UNION_TYPE
2052 && TYPE_TRANSPARENT_UNION (passed_type
))
2053 passed_type
= TREE_TYPE (TYPE_FIELDS (passed_type
));
2055 /* See if this arg was passed by invisible reference. */
2056 if (pass_by_reference (&all
->args_so_far
, passed_mode
,
2057 passed_type
, data
->named_arg
))
2059 passed_type
= nominal_type
= build_pointer_type (passed_type
);
2060 data
->passed_pointer
= true;
2061 passed_mode
= nominal_mode
= Pmode
;
2064 /* Find mode as it is passed by the ABI. */
2065 promoted_mode
= passed_mode
;
2066 if (targetm
.calls
.promote_function_args (TREE_TYPE (current_function_decl
)))
2068 int unsignedp
= TYPE_UNSIGNED (passed_type
);
2069 promoted_mode
= promote_mode (passed_type
, promoted_mode
,
2074 data
->nominal_type
= nominal_type
;
2075 data
->passed_type
= passed_type
;
2076 data
->nominal_mode
= nominal_mode
;
2077 data
->passed_mode
= passed_mode
;
2078 data
->promoted_mode
= promoted_mode
;
2081 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2084 assign_parms_setup_varargs (struct assign_parm_data_all
*all
,
2085 struct assign_parm_data_one
*data
, bool no_rtl
)
2087 int varargs_pretend_bytes
= 0;
2089 targetm
.calls
.setup_incoming_varargs (&all
->args_so_far
,
2090 data
->promoted_mode
,
2092 &varargs_pretend_bytes
, no_rtl
);
2094 /* If the back-end has requested extra stack space, record how much is
2095 needed. Do not change pretend_args_size otherwise since it may be
2096 nonzero from an earlier partial argument. */
2097 if (varargs_pretend_bytes
> 0)
2098 all
->pretend_args_size
= varargs_pretend_bytes
;
2101 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2102 the incoming location of the current parameter. */
2105 assign_parm_find_entry_rtl (struct assign_parm_data_all
*all
,
2106 struct assign_parm_data_one
*data
)
2108 HOST_WIDE_INT pretend_bytes
= 0;
2112 if (data
->promoted_mode
== VOIDmode
)
2114 data
->entry_parm
= data
->stack_parm
= const0_rtx
;
2118 #ifdef FUNCTION_INCOMING_ARG
2119 entry_parm
= FUNCTION_INCOMING_ARG (all
->args_so_far
, data
->promoted_mode
,
2120 data
->passed_type
, data
->named_arg
);
2122 entry_parm
= FUNCTION_ARG (all
->args_so_far
, data
->promoted_mode
,
2123 data
->passed_type
, data
->named_arg
);
2126 if (entry_parm
== 0)
2127 data
->promoted_mode
= data
->passed_mode
;
2129 /* Determine parm's home in the stack, in case it arrives in the stack
2130 or we should pretend it did. Compute the stack position and rtx where
2131 the argument arrives and its size.
2133 There is one complexity here: If this was a parameter that would
2134 have been passed in registers, but wasn't only because it is
2135 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2136 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2137 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2138 as it was the previous time. */
2139 in_regs
= entry_parm
!= 0;
2140 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2143 if (!in_regs
&& !data
->named_arg
)
2145 if (targetm
.calls
.pretend_outgoing_varargs_named (&all
->args_so_far
))
2148 #ifdef FUNCTION_INCOMING_ARG
2149 tem
= FUNCTION_INCOMING_ARG (all
->args_so_far
, data
->promoted_mode
,
2150 data
->passed_type
, true);
2152 tem
= FUNCTION_ARG (all
->args_so_far
, data
->promoted_mode
,
2153 data
->passed_type
, true);
2155 in_regs
= tem
!= NULL
;
2159 /* If this parameter was passed both in registers and in the stack, use
2160 the copy on the stack. */
2161 if (targetm
.calls
.must_pass_in_stack (data
->promoted_mode
,
2169 partial
= targetm
.calls
.arg_partial_bytes (&all
->args_so_far
,
2170 data
->promoted_mode
,
2173 data
->partial
= partial
;
2175 /* The caller might already have allocated stack space for the
2176 register parameters. */
2177 if (partial
!= 0 && all
->reg_parm_stack_space
== 0)
2179 /* Part of this argument is passed in registers and part
2180 is passed on the stack. Ask the prologue code to extend
2181 the stack part so that we can recreate the full value.
2183 PRETEND_BYTES is the size of the registers we need to store.
2184 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2185 stack space that the prologue should allocate.
2187 Internally, gcc assumes that the argument pointer is aligned
2188 to STACK_BOUNDARY bits. This is used both for alignment
2189 optimizations (see init_emit) and to locate arguments that are
2190 aligned to more than PARM_BOUNDARY bits. We must preserve this
2191 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2192 a stack boundary. */
2194 /* We assume at most one partial arg, and it must be the first
2195 argument on the stack. */
2196 gcc_assert (!all
->extra_pretend_bytes
&& !all
->pretend_args_size
);
2198 pretend_bytes
= partial
;
2199 all
->pretend_args_size
= CEIL_ROUND (pretend_bytes
, STACK_BYTES
);
2201 /* We want to align relative to the actual stack pointer, so
2202 don't include this in the stack size until later. */
2203 all
->extra_pretend_bytes
= all
->pretend_args_size
;
2207 locate_and_pad_parm (data
->promoted_mode
, data
->passed_type
, in_regs
,
2208 entry_parm
? data
->partial
: 0, current_function_decl
,
2209 &all
->stack_args_size
, &data
->locate
);
2211 /* Adjust offsets to include the pretend args. */
2212 pretend_bytes
= all
->extra_pretend_bytes
- pretend_bytes
;
2213 data
->locate
.slot_offset
.constant
+= pretend_bytes
;
2214 data
->locate
.offset
.constant
+= pretend_bytes
;
2216 data
->entry_parm
= entry_parm
;
2219 /* A subroutine of assign_parms. If there is actually space on the stack
2220 for this parm, count it in stack_args_size and return true. */
2223 assign_parm_is_stack_parm (struct assign_parm_data_all
*all
,
2224 struct assign_parm_data_one
*data
)
2226 /* Trivially true if we've no incoming register. */
2227 if (data
->entry_parm
== NULL
)
2229 /* Also true if we're partially in registers and partially not,
2230 since we've arranged to drop the entire argument on the stack. */
2231 else if (data
->partial
!= 0)
2233 /* Also true if the target says that it's passed in both registers
2234 and on the stack. */
2235 else if (GET_CODE (data
->entry_parm
) == PARALLEL
2236 && XEXP (XVECEXP (data
->entry_parm
, 0, 0), 0) == NULL_RTX
)
2238 /* Also true if the target says that there's stack allocated for
2239 all register parameters. */
2240 else if (all
->reg_parm_stack_space
> 0)
2242 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2246 all
->stack_args_size
.constant
+= data
->locate
.size
.constant
;
2247 if (data
->locate
.size
.var
)
2248 ADD_PARM_SIZE (all
->stack_args_size
, data
->locate
.size
.var
);
2253 /* A subroutine of assign_parms. Given that this parameter is allocated
2254 stack space by the ABI, find it. */
2257 assign_parm_find_stack_rtl (tree parm
, struct assign_parm_data_one
*data
)
2259 rtx offset_rtx
, stack_parm
;
2260 unsigned int align
, boundary
;
2262 /* If we're passing this arg using a reg, make its stack home the
2263 aligned stack slot. */
2264 if (data
->entry_parm
)
2265 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.slot_offset
);
2267 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.offset
);
2269 stack_parm
= current_function_internal_arg_pointer
;
2270 if (offset_rtx
!= const0_rtx
)
2271 stack_parm
= gen_rtx_PLUS (Pmode
, stack_parm
, offset_rtx
);
2272 stack_parm
= gen_rtx_MEM (data
->promoted_mode
, stack_parm
);
2274 set_mem_attributes (stack_parm
, parm
, 1);
2276 boundary
= data
->locate
.boundary
;
2277 align
= BITS_PER_UNIT
;
2279 /* If we're padding upward, we know that the alignment of the slot
2280 is FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2281 intentionally forcing upward padding. Otherwise we have to come
2282 up with a guess at the alignment based on OFFSET_RTX. */
2283 if (data
->locate
.where_pad
!= downward
|| data
->entry_parm
)
2285 else if (GET_CODE (offset_rtx
) == CONST_INT
)
2287 align
= INTVAL (offset_rtx
) * BITS_PER_UNIT
| boundary
;
2288 align
= align
& -align
;
2290 set_mem_align (stack_parm
, align
);
2292 if (data
->entry_parm
)
2293 set_reg_attrs_for_parm (data
->entry_parm
, stack_parm
);
2295 data
->stack_parm
= stack_parm
;
2298 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2299 always valid and contiguous. */
2302 assign_parm_adjust_entry_rtl (struct assign_parm_data_one
*data
)
2304 rtx entry_parm
= data
->entry_parm
;
2305 rtx stack_parm
= data
->stack_parm
;
2307 /* If this parm was passed part in regs and part in memory, pretend it
2308 arrived entirely in memory by pushing the register-part onto the stack.
2309 In the special case of a DImode or DFmode that is split, we could put
2310 it together in a pseudoreg directly, but for now that's not worth
2312 if (data
->partial
!= 0)
2314 /* Handle calls that pass values in multiple non-contiguous
2315 locations. The Irix 6 ABI has examples of this. */
2316 if (GET_CODE (entry_parm
) == PARALLEL
)
2317 emit_group_store (validize_mem (stack_parm
), entry_parm
,
2319 int_size_in_bytes (data
->passed_type
));
2322 gcc_assert (data
->partial
% UNITS_PER_WORD
== 0);
2323 move_block_from_reg (REGNO (entry_parm
), validize_mem (stack_parm
),
2324 data
->partial
/ UNITS_PER_WORD
);
2327 entry_parm
= stack_parm
;
2330 /* If we didn't decide this parm came in a register, by default it came
2332 else if (entry_parm
== NULL
)
2333 entry_parm
= stack_parm
;
2335 /* When an argument is passed in multiple locations, we can't make use
2336 of this information, but we can save some copying if the whole argument
2337 is passed in a single register. */
2338 else if (GET_CODE (entry_parm
) == PARALLEL
2339 && data
->nominal_mode
!= BLKmode
2340 && data
->passed_mode
!= BLKmode
)
2342 size_t i
, len
= XVECLEN (entry_parm
, 0);
2344 for (i
= 0; i
< len
; i
++)
2345 if (XEXP (XVECEXP (entry_parm
, 0, i
), 0) != NULL_RTX
2346 && REG_P (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2347 && (GET_MODE (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2348 == data
->passed_mode
)
2349 && INTVAL (XEXP (XVECEXP (entry_parm
, 0, i
), 1)) == 0)
2351 entry_parm
= XEXP (XVECEXP (entry_parm
, 0, i
), 0);
2356 data
->entry_parm
= entry_parm
;
2359 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2360 always valid and properly aligned. */
2363 assign_parm_adjust_stack_rtl (struct assign_parm_data_one
*data
)
2365 rtx stack_parm
= data
->stack_parm
;
2367 /* If we can't trust the parm stack slot to be aligned enough for its
2368 ultimate type, don't use that slot after entry. We'll make another
2369 stack slot, if we need one. */
2371 && ((STRICT_ALIGNMENT
2372 && GET_MODE_ALIGNMENT (data
->nominal_mode
) > MEM_ALIGN (stack_parm
))
2373 || (data
->nominal_type
2374 && TYPE_ALIGN (data
->nominal_type
) > MEM_ALIGN (stack_parm
)
2375 && MEM_ALIGN (stack_parm
) < PREFERRED_STACK_BOUNDARY
)))
2378 /* If parm was passed in memory, and we need to convert it on entry,
2379 don't store it back in that same slot. */
2380 else if (data
->entry_parm
== stack_parm
2381 && data
->nominal_mode
!= BLKmode
2382 && data
->nominal_mode
!= data
->passed_mode
)
2385 /* If stack protection is in effect for this function, don't leave any
2386 pointers in their passed stack slots. */
2387 else if (cfun
->stack_protect_guard
2388 && (flag_stack_protect
== 2
2389 || data
->passed_pointer
2390 || POINTER_TYPE_P (data
->nominal_type
)))
2393 data
->stack_parm
= stack_parm
;
2396 /* A subroutine of assign_parms. Return true if the current parameter
2397 should be stored as a BLKmode in the current frame. */
2400 assign_parm_setup_block_p (struct assign_parm_data_one
*data
)
2402 if (data
->nominal_mode
== BLKmode
)
2404 if (GET_CODE (data
->entry_parm
) == PARALLEL
)
2407 #ifdef BLOCK_REG_PADDING
2408 /* Only assign_parm_setup_block knows how to deal with register arguments
2409 that are padded at the least significant end. */
2410 if (REG_P (data
->entry_parm
)
2411 && GET_MODE_SIZE (data
->promoted_mode
) < UNITS_PER_WORD
2412 && (BLOCK_REG_PADDING (data
->passed_mode
, data
->passed_type
, 1)
2413 == (BYTES_BIG_ENDIAN
? upward
: downward
)))
2420 /* A subroutine of assign_parms. Arrange for the parameter to be
2421 present and valid in DATA->STACK_RTL. */
2424 assign_parm_setup_block (struct assign_parm_data_all
*all
,
2425 tree parm
, struct assign_parm_data_one
*data
)
2427 rtx entry_parm
= data
->entry_parm
;
2428 rtx stack_parm
= data
->stack_parm
;
2430 HOST_WIDE_INT size_stored
;
2431 rtx orig_entry_parm
= entry_parm
;
2433 if (GET_CODE (entry_parm
) == PARALLEL
)
2434 entry_parm
= emit_group_move_into_temps (entry_parm
);
2436 /* If we've a non-block object that's nevertheless passed in parts,
2437 reconstitute it in register operations rather than on the stack. */
2438 if (GET_CODE (entry_parm
) == PARALLEL
2439 && data
->nominal_mode
!= BLKmode
)
2441 rtx elt0
= XEXP (XVECEXP (orig_entry_parm
, 0, 0), 0);
2443 if ((XVECLEN (entry_parm
, 0) > 1
2444 || hard_regno_nregs
[REGNO (elt0
)][GET_MODE (elt0
)] > 1)
2445 && use_register_for_decl (parm
))
2447 rtx parmreg
= gen_reg_rtx (data
->nominal_mode
);
2449 push_to_sequence2 (all
->first_conversion_insn
,
2450 all
->last_conversion_insn
);
2452 /* For values returned in multiple registers, handle possible
2453 incompatible calls to emit_group_store.
2455 For example, the following would be invalid, and would have to
2456 be fixed by the conditional below:
2458 emit_group_store ((reg:SF), (parallel:DF))
2459 emit_group_store ((reg:SI), (parallel:DI))
2461 An example of this are doubles in e500 v2:
2462 (parallel:DF (expr_list (reg:SI) (const_int 0))
2463 (expr_list (reg:SI) (const_int 4))). */
2464 if (data
->nominal_mode
!= data
->passed_mode
)
2466 rtx t
= gen_reg_rtx (GET_MODE (entry_parm
));
2467 emit_group_store (t
, entry_parm
, NULL_TREE
,
2468 GET_MODE_SIZE (GET_MODE (entry_parm
)));
2469 convert_move (parmreg
, t
, 0);
2472 emit_group_store (parmreg
, entry_parm
, data
->nominal_type
,
2473 int_size_in_bytes (data
->nominal_type
));
2475 all
->first_conversion_insn
= get_insns ();
2476 all
->last_conversion_insn
= get_last_insn ();
2479 SET_DECL_RTL (parm
, parmreg
);
2484 size
= int_size_in_bytes (data
->passed_type
);
2485 size_stored
= CEIL_ROUND (size
, UNITS_PER_WORD
);
2486 if (stack_parm
== 0)
2488 DECL_ALIGN (parm
) = MAX (DECL_ALIGN (parm
), BITS_PER_WORD
);
2489 stack_parm
= assign_stack_local (BLKmode
, size_stored
,
2491 if (GET_MODE_SIZE (GET_MODE (entry_parm
)) == size
)
2492 PUT_MODE (stack_parm
, GET_MODE (entry_parm
));
2493 set_mem_attributes (stack_parm
, parm
, 1);
2496 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2497 calls that pass values in multiple non-contiguous locations. */
2498 if (REG_P (entry_parm
) || GET_CODE (entry_parm
) == PARALLEL
)
2502 /* Note that we will be storing an integral number of words.
2503 So we have to be careful to ensure that we allocate an
2504 integral number of words. We do this above when we call
2505 assign_stack_local if space was not allocated in the argument
2506 list. If it was, this will not work if PARM_BOUNDARY is not
2507 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2508 if it becomes a problem. Exception is when BLKmode arrives
2509 with arguments not conforming to word_mode. */
2511 if (data
->stack_parm
== 0)
2513 else if (GET_CODE (entry_parm
) == PARALLEL
)
2516 gcc_assert (!size
|| !(PARM_BOUNDARY
% BITS_PER_WORD
));
2518 mem
= validize_mem (stack_parm
);
2520 /* Handle values in multiple non-contiguous locations. */
2521 if (GET_CODE (entry_parm
) == PARALLEL
)
2523 push_to_sequence2 (all
->first_conversion_insn
,
2524 all
->last_conversion_insn
);
2525 emit_group_store (mem
, entry_parm
, data
->passed_type
, size
);
2526 all
->first_conversion_insn
= get_insns ();
2527 all
->last_conversion_insn
= get_last_insn ();
2534 /* If SIZE is that of a mode no bigger than a word, just use
2535 that mode's store operation. */
2536 else if (size
<= UNITS_PER_WORD
)
2538 enum machine_mode mode
2539 = mode_for_size (size
* BITS_PER_UNIT
, MODE_INT
, 0);
2542 #ifdef BLOCK_REG_PADDING
2543 && (size
== UNITS_PER_WORD
2544 || (BLOCK_REG_PADDING (mode
, data
->passed_type
, 1)
2545 != (BYTES_BIG_ENDIAN
? upward
: downward
)))
2551 /* We are really truncating a word_mode value containing
2552 SIZE bytes into a value of mode MODE. If such an
2553 operation requires no actual instructions, we can refer
2554 to the value directly in mode MODE, otherwise we must
2555 start with the register in word_mode and explicitly
2557 if (TRULY_NOOP_TRUNCATION (size
* BITS_PER_UNIT
, BITS_PER_WORD
))
2558 reg
= gen_rtx_REG (mode
, REGNO (entry_parm
));
2561 reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
2562 reg
= convert_to_mode (mode
, copy_to_reg (reg
), 1);
2564 emit_move_insn (change_address (mem
, mode
, 0), reg
);
2567 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
2568 machine must be aligned to the left before storing
2569 to memory. Note that the previous test doesn't
2570 handle all cases (e.g. SIZE == 3). */
2571 else if (size
!= UNITS_PER_WORD
2572 #ifdef BLOCK_REG_PADDING
2573 && (BLOCK_REG_PADDING (mode
, data
->passed_type
, 1)
2581 int by
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
2582 rtx reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
2584 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
,
2585 build_int_cst (NULL_TREE
, by
),
2587 tem
= change_address (mem
, word_mode
, 0);
2588 emit_move_insn (tem
, x
);
2591 move_block_from_reg (REGNO (entry_parm
), mem
,
2592 size_stored
/ UNITS_PER_WORD
);
2595 move_block_from_reg (REGNO (entry_parm
), mem
,
2596 size_stored
/ UNITS_PER_WORD
);
2598 else if (data
->stack_parm
== 0)
2600 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2601 emit_block_move (stack_parm
, data
->entry_parm
, GEN_INT (size
),
2603 all
->first_conversion_insn
= get_insns ();
2604 all
->last_conversion_insn
= get_last_insn ();
2608 data
->stack_parm
= stack_parm
;
2609 SET_DECL_RTL (parm
, stack_parm
);
2612 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
2613 parameter. Get it there. Perform all ABI specified conversions. */
2616 assign_parm_setup_reg (struct assign_parm_data_all
*all
, tree parm
,
2617 struct assign_parm_data_one
*data
)
2620 enum machine_mode promoted_nominal_mode
;
2621 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (parm
));
2622 bool did_conversion
= false;
2624 /* Store the parm in a pseudoregister during the function, but we may
2625 need to do it in a wider mode. */
2627 /* This is not really promoting for a call. However we need to be
2628 consistent with assign_parm_find_data_types and expand_expr_real_1. */
2629 promoted_nominal_mode
2630 = promote_mode (data
->nominal_type
, data
->nominal_mode
, &unsignedp
, 1);
2632 parmreg
= gen_reg_rtx (promoted_nominal_mode
);
2634 if (!DECL_ARTIFICIAL (parm
))
2635 mark_user_reg (parmreg
);
2637 /* If this was an item that we received a pointer to,
2638 set DECL_RTL appropriately. */
2639 if (data
->passed_pointer
)
2641 rtx x
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data
->passed_type
)), parmreg
);
2642 set_mem_attributes (x
, parm
, 1);
2643 SET_DECL_RTL (parm
, x
);
2646 SET_DECL_RTL (parm
, parmreg
);
2648 /* Copy the value into the register. */
2649 if (data
->nominal_mode
!= data
->passed_mode
2650 || promoted_nominal_mode
!= data
->promoted_mode
)
2654 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
2655 mode, by the caller. We now have to convert it to
2656 NOMINAL_MODE, if different. However, PARMREG may be in
2657 a different mode than NOMINAL_MODE if it is being stored
2660 If ENTRY_PARM is a hard register, it might be in a register
2661 not valid for operating in its mode (e.g., an odd-numbered
2662 register for a DFmode). In that case, moves are the only
2663 thing valid, so we can't do a convert from there. This
2664 occurs when the calling sequence allow such misaligned
2667 In addition, the conversion may involve a call, which could
2668 clobber parameters which haven't been copied to pseudo
2669 registers yet. Therefore, we must first copy the parm to
2670 a pseudo reg here, and save the conversion until after all
2671 parameters have been moved. */
2673 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
2675 emit_move_insn (tempreg
, validize_mem (data
->entry_parm
));
2677 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2678 tempreg
= convert_to_mode (data
->nominal_mode
, tempreg
, unsignedp
);
2680 if (GET_CODE (tempreg
) == SUBREG
2681 && GET_MODE (tempreg
) == data
->nominal_mode
2682 && REG_P (SUBREG_REG (tempreg
))
2683 && data
->nominal_mode
== data
->passed_mode
2684 && GET_MODE (SUBREG_REG (tempreg
)) == GET_MODE (data
->entry_parm
)
2685 && GET_MODE_SIZE (GET_MODE (tempreg
))
2686 < GET_MODE_SIZE (GET_MODE (data
->entry_parm
)))
2688 /* The argument is already sign/zero extended, so note it
2690 SUBREG_PROMOTED_VAR_P (tempreg
) = 1;
2691 SUBREG_PROMOTED_UNSIGNED_SET (tempreg
, unsignedp
);
2694 /* TREE_USED gets set erroneously during expand_assignment. */
2695 save_tree_used
= TREE_USED (parm
);
2696 expand_assignment (parm
, make_tree (data
->nominal_type
, tempreg
), false);
2697 TREE_USED (parm
) = save_tree_used
;
2698 all
->first_conversion_insn
= get_insns ();
2699 all
->last_conversion_insn
= get_last_insn ();
2702 did_conversion
= true;
2705 emit_move_insn (parmreg
, validize_mem (data
->entry_parm
));
2707 /* If we were passed a pointer but the actual value can safely live
2708 in a register, put it in one. */
2709 if (data
->passed_pointer
2710 && TYPE_MODE (TREE_TYPE (parm
)) != BLKmode
2711 /* If by-reference argument was promoted, demote it. */
2712 && (TYPE_MODE (TREE_TYPE (parm
)) != GET_MODE (DECL_RTL (parm
))
2713 || use_register_for_decl (parm
)))
2715 /* We can't use nominal_mode, because it will have been set to
2716 Pmode above. We must use the actual mode of the parm. */
2717 parmreg
= gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm
)));
2718 mark_user_reg (parmreg
);
2720 if (GET_MODE (parmreg
) != GET_MODE (DECL_RTL (parm
)))
2722 rtx tempreg
= gen_reg_rtx (GET_MODE (DECL_RTL (parm
)));
2723 int unsigned_p
= TYPE_UNSIGNED (TREE_TYPE (parm
));
2725 push_to_sequence2 (all
->first_conversion_insn
,
2726 all
->last_conversion_insn
);
2727 emit_move_insn (tempreg
, DECL_RTL (parm
));
2728 tempreg
= convert_to_mode (GET_MODE (parmreg
), tempreg
, unsigned_p
);
2729 emit_move_insn (parmreg
, tempreg
);
2730 all
->first_conversion_insn
= get_insns ();
2731 all
->last_conversion_insn
= get_last_insn ();
2734 did_conversion
= true;
2737 emit_move_insn (parmreg
, DECL_RTL (parm
));
2739 SET_DECL_RTL (parm
, parmreg
);
2741 /* STACK_PARM is the pointer, not the parm, and PARMREG is
2743 data
->stack_parm
= NULL
;
2746 /* Mark the register as eliminable if we did no conversion and it was
2747 copied from memory at a fixed offset, and the arg pointer was not
2748 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
2749 offset formed an invalid address, such memory-equivalences as we
2750 make here would screw up life analysis for it. */
2751 if (data
->nominal_mode
== data
->passed_mode
2753 && data
->stack_parm
!= 0
2754 && MEM_P (data
->stack_parm
)
2755 && data
->locate
.offset
.var
== 0
2756 && reg_mentioned_p (virtual_incoming_args_rtx
,
2757 XEXP (data
->stack_parm
, 0)))
2759 rtx linsn
= get_last_insn ();
2762 /* Mark complex types separately. */
2763 if (GET_CODE (parmreg
) == CONCAT
)
2765 enum machine_mode submode
2766 = GET_MODE_INNER (GET_MODE (parmreg
));
2767 int regnor
= REGNO (XEXP (parmreg
, 0));
2768 int regnoi
= REGNO (XEXP (parmreg
, 1));
2769 rtx stackr
= adjust_address_nv (data
->stack_parm
, submode
, 0);
2770 rtx stacki
= adjust_address_nv (data
->stack_parm
, submode
,
2771 GET_MODE_SIZE (submode
));
2773 /* Scan backwards for the set of the real and
2775 for (sinsn
= linsn
; sinsn
!= 0;
2776 sinsn
= prev_nonnote_insn (sinsn
))
2778 set
= single_set (sinsn
);
2782 if (SET_DEST (set
) == regno_reg_rtx
[regnoi
])
2783 set_unique_reg_note (sinsn
, REG_EQUIV
, stacki
);
2784 else if (SET_DEST (set
) == regno_reg_rtx
[regnor
])
2785 set_unique_reg_note (sinsn
, REG_EQUIV
, stackr
);
2788 else if ((set
= single_set (linsn
)) != 0
2789 && SET_DEST (set
) == parmreg
)
2790 set_unique_reg_note (linsn
, REG_EQUIV
, data
->stack_parm
);
2793 /* For pointer data type, suggest pointer register. */
2794 if (POINTER_TYPE_P (TREE_TYPE (parm
)))
2795 mark_reg_pointer (parmreg
,
2796 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
2799 /* A subroutine of assign_parms. Allocate stack space to hold the current
2800 parameter. Get it there. Perform all ABI specified conversions. */
2803 assign_parm_setup_stack (struct assign_parm_data_all
*all
, tree parm
,
2804 struct assign_parm_data_one
*data
)
2806 /* Value must be stored in the stack slot STACK_PARM during function
2808 bool to_conversion
= false;
2810 if (data
->promoted_mode
!= data
->nominal_mode
)
2812 /* Conversion is required. */
2813 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
2815 emit_move_insn (tempreg
, validize_mem (data
->entry_parm
));
2817 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2818 to_conversion
= true;
2820 data
->entry_parm
= convert_to_mode (data
->nominal_mode
, tempreg
,
2821 TYPE_UNSIGNED (TREE_TYPE (parm
)));
2823 if (data
->stack_parm
)
2824 /* ??? This may need a big-endian conversion on sparc64. */
2826 = adjust_address (data
->stack_parm
, data
->nominal_mode
, 0);
2829 if (data
->entry_parm
!= data
->stack_parm
)
2833 if (data
->stack_parm
== 0)
2836 = assign_stack_local (GET_MODE (data
->entry_parm
),
2837 GET_MODE_SIZE (GET_MODE (data
->entry_parm
)),
2838 TYPE_ALIGN (data
->passed_type
));
2839 set_mem_attributes (data
->stack_parm
, parm
, 1);
2842 dest
= validize_mem (data
->stack_parm
);
2843 src
= validize_mem (data
->entry_parm
);
2847 /* Use a block move to handle potentially misaligned entry_parm. */
2849 push_to_sequence2 (all
->first_conversion_insn
,
2850 all
->last_conversion_insn
);
2851 to_conversion
= true;
2853 emit_block_move (dest
, src
,
2854 GEN_INT (int_size_in_bytes (data
->passed_type
)),
2858 emit_move_insn (dest
, src
);
2863 all
->first_conversion_insn
= get_insns ();
2864 all
->last_conversion_insn
= get_last_insn ();
2868 SET_DECL_RTL (parm
, data
->stack_parm
);
2871 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
2872 undo the frobbing that we did in assign_parms_augmented_arg_list. */
2875 assign_parms_unsplit_complex (struct assign_parm_data_all
*all
, tree fnargs
)
2878 tree orig_fnargs
= all
->orig_fnargs
;
2880 for (parm
= orig_fnargs
; parm
; parm
= TREE_CHAIN (parm
))
2882 if (TREE_CODE (TREE_TYPE (parm
)) == COMPLEX_TYPE
2883 && targetm
.calls
.split_complex_arg (TREE_TYPE (parm
)))
2885 rtx tmp
, real
, imag
;
2886 enum machine_mode inner
= GET_MODE_INNER (DECL_MODE (parm
));
2888 real
= DECL_RTL (fnargs
);
2889 imag
= DECL_RTL (TREE_CHAIN (fnargs
));
2890 if (inner
!= GET_MODE (real
))
2892 real
= gen_lowpart_SUBREG (inner
, real
);
2893 imag
= gen_lowpart_SUBREG (inner
, imag
);
2896 if (TREE_ADDRESSABLE (parm
))
2899 HOST_WIDE_INT size
= int_size_in_bytes (TREE_TYPE (parm
));
2901 /* split_complex_arg put the real and imag parts in
2902 pseudos. Move them to memory. */
2903 tmp
= assign_stack_local (DECL_MODE (parm
), size
,
2904 TYPE_ALIGN (TREE_TYPE (parm
)));
2905 set_mem_attributes (tmp
, parm
, 1);
2906 rmem
= adjust_address_nv (tmp
, inner
, 0);
2907 imem
= adjust_address_nv (tmp
, inner
, GET_MODE_SIZE (inner
));
2908 push_to_sequence2 (all
->first_conversion_insn
,
2909 all
->last_conversion_insn
);
2910 emit_move_insn (rmem
, real
);
2911 emit_move_insn (imem
, imag
);
2912 all
->first_conversion_insn
= get_insns ();
2913 all
->last_conversion_insn
= get_last_insn ();
2917 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
2918 SET_DECL_RTL (parm
, tmp
);
2920 real
= DECL_INCOMING_RTL (fnargs
);
2921 imag
= DECL_INCOMING_RTL (TREE_CHAIN (fnargs
));
2922 if (inner
!= GET_MODE (real
))
2924 real
= gen_lowpart_SUBREG (inner
, real
);
2925 imag
= gen_lowpart_SUBREG (inner
, imag
);
2927 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
2928 set_decl_incoming_rtl (parm
, tmp
, false);
2929 fnargs
= TREE_CHAIN (fnargs
);
2933 SET_DECL_RTL (parm
, DECL_RTL (fnargs
));
2934 set_decl_incoming_rtl (parm
, DECL_INCOMING_RTL (fnargs
), false);
2936 /* Set MEM_EXPR to the original decl, i.e. to PARM,
2937 instead of the copy of decl, i.e. FNARGS. */
2938 if (DECL_INCOMING_RTL (parm
) && MEM_P (DECL_INCOMING_RTL (parm
)))
2939 set_mem_expr (DECL_INCOMING_RTL (parm
), parm
);
2942 fnargs
= TREE_CHAIN (fnargs
);
2946 /* Assign RTL expressions to the function's parameters. This may involve
2947 copying them into registers and using those registers as the DECL_RTL. */
2950 assign_parms (tree fndecl
)
2952 struct assign_parm_data_all all
;
2955 current_function_internal_arg_pointer
2956 = targetm
.calls
.internal_arg_pointer ();
2958 assign_parms_initialize_all (&all
);
2959 fnargs
= assign_parms_augmented_arg_list (&all
);
2961 for (parm
= fnargs
; parm
; parm
= TREE_CHAIN (parm
))
2963 struct assign_parm_data_one data
;
2965 /* Extract the type of PARM; adjust it according to ABI. */
2966 assign_parm_find_data_types (&all
, parm
, &data
);
2968 /* Early out for errors and void parameters. */
2969 if (data
.passed_mode
== VOIDmode
)
2971 SET_DECL_RTL (parm
, const0_rtx
);
2972 DECL_INCOMING_RTL (parm
) = DECL_RTL (parm
);
2976 if (current_function_stdarg
&& !TREE_CHAIN (parm
))
2977 assign_parms_setup_varargs (&all
, &data
, false);
2979 /* Find out where the parameter arrives in this function. */
2980 assign_parm_find_entry_rtl (&all
, &data
);
2982 /* Find out where stack space for this parameter might be. */
2983 if (assign_parm_is_stack_parm (&all
, &data
))
2985 assign_parm_find_stack_rtl (parm
, &data
);
2986 assign_parm_adjust_entry_rtl (&data
);
2989 /* Record permanently how this parm was passed. */
2990 set_decl_incoming_rtl (parm
, data
.entry_parm
, data
.passed_pointer
);
2992 /* Update info on where next arg arrives in registers. */
2993 FUNCTION_ARG_ADVANCE (all
.args_so_far
, data
.promoted_mode
,
2994 data
.passed_type
, data
.named_arg
);
2996 assign_parm_adjust_stack_rtl (&data
);
2998 if (assign_parm_setup_block_p (&data
))
2999 assign_parm_setup_block (&all
, parm
, &data
);
3000 else if (data
.passed_pointer
|| use_register_for_decl (parm
))
3001 assign_parm_setup_reg (&all
, parm
, &data
);
3003 assign_parm_setup_stack (&all
, parm
, &data
);
3006 if (targetm
.calls
.split_complex_arg
&& fnargs
!= all
.orig_fnargs
)
3007 assign_parms_unsplit_complex (&all
, fnargs
);
3009 /* Output all parameter conversion instructions (possibly including calls)
3010 now that all parameters have been copied out of hard registers. */
3011 emit_insn (all
.first_conversion_insn
);
3013 /* If we are receiving a struct value address as the first argument, set up
3014 the RTL for the function result. As this might require code to convert
3015 the transmitted address to Pmode, we do this here to ensure that possible
3016 preliminary conversions of the address have been emitted already. */
3017 if (all
.function_result_decl
)
3019 tree result
= DECL_RESULT (current_function_decl
);
3020 rtx addr
= DECL_RTL (all
.function_result_decl
);
3023 if (DECL_BY_REFERENCE (result
))
3027 addr
= convert_memory_address (Pmode
, addr
);
3028 x
= gen_rtx_MEM (DECL_MODE (result
), addr
);
3029 set_mem_attributes (x
, result
, 1);
3031 SET_DECL_RTL (result
, x
);
3034 /* We have aligned all the args, so add space for the pretend args. */
3035 current_function_pretend_args_size
= all
.pretend_args_size
;
3036 all
.stack_args_size
.constant
+= all
.extra_pretend_bytes
;
3037 current_function_args_size
= all
.stack_args_size
.constant
;
3039 /* Adjust function incoming argument size for alignment and
3042 #ifdef REG_PARM_STACK_SPACE
3043 current_function_args_size
= MAX (current_function_args_size
,
3044 REG_PARM_STACK_SPACE (fndecl
));
3047 current_function_args_size
= CEIL_ROUND (current_function_args_size
,
3048 PARM_BOUNDARY
/ BITS_PER_UNIT
);
3050 #ifdef ARGS_GROW_DOWNWARD
3051 current_function_arg_offset_rtx
3052 = (all
.stack_args_size
.var
== 0 ? GEN_INT (-all
.stack_args_size
.constant
)
3053 : expand_expr (size_diffop (all
.stack_args_size
.var
,
3054 size_int (-all
.stack_args_size
.constant
)),
3055 NULL_RTX
, VOIDmode
, 0));
3057 current_function_arg_offset_rtx
= ARGS_SIZE_RTX (all
.stack_args_size
);
3060 /* See how many bytes, if any, of its args a function should try to pop
3063 current_function_pops_args
= RETURN_POPS_ARGS (fndecl
, TREE_TYPE (fndecl
),
3064 current_function_args_size
);
3066 /* For stdarg.h function, save info about
3067 regs and stack space used by the named args. */
3069 current_function_args_info
= all
.args_so_far
;
3071 /* Set the rtx used for the function return value. Put this in its
3072 own variable so any optimizers that need this information don't have
3073 to include tree.h. Do this here so it gets done when an inlined
3074 function gets output. */
3076 current_function_return_rtx
3077 = (DECL_RTL_SET_P (DECL_RESULT (fndecl
))
3078 ? DECL_RTL (DECL_RESULT (fndecl
)) : NULL_RTX
);
3080 /* If scalar return value was computed in a pseudo-reg, or was a named
3081 return value that got dumped to the stack, copy that to the hard
3083 if (DECL_RTL_SET_P (DECL_RESULT (fndecl
)))
3085 tree decl_result
= DECL_RESULT (fndecl
);
3086 rtx decl_rtl
= DECL_RTL (decl_result
);
3088 if (REG_P (decl_rtl
)
3089 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
3090 : DECL_REGISTER (decl_result
))
3094 real_decl_rtl
= targetm
.calls
.function_value (TREE_TYPE (decl_result
),
3096 REG_FUNCTION_VALUE_P (real_decl_rtl
) = 1;
3097 /* The delay slot scheduler assumes that current_function_return_rtx
3098 holds the hard register containing the return value, not a
3099 temporary pseudo. */
3100 current_function_return_rtx
= real_decl_rtl
;
3105 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3106 For all seen types, gimplify their sizes. */
3109 gimplify_parm_type (tree
*tp
, int *walk_subtrees
, void *data
)
3116 if (POINTER_TYPE_P (t
))
3118 else if (TYPE_SIZE (t
) && !TREE_CONSTANT (TYPE_SIZE (t
))
3119 && !TYPE_SIZES_GIMPLIFIED (t
))
3121 gimplify_type_sizes (t
, (tree
*) data
);
3129 /* Gimplify the parameter list for current_function_decl. This involves
3130 evaluating SAVE_EXPRs of variable sized parameters and generating code
3131 to implement callee-copies reference parameters. Returns a list of
3132 statements to add to the beginning of the function, or NULL if nothing
3136 gimplify_parameters (void)
3138 struct assign_parm_data_all all
;
3139 tree fnargs
, parm
, stmts
= NULL
;
3141 assign_parms_initialize_all (&all
);
3142 fnargs
= assign_parms_augmented_arg_list (&all
);
3144 for (parm
= fnargs
; parm
; parm
= TREE_CHAIN (parm
))
3146 struct assign_parm_data_one data
;
3148 /* Extract the type of PARM; adjust it according to ABI. */
3149 assign_parm_find_data_types (&all
, parm
, &data
);
3151 /* Early out for errors and void parameters. */
3152 if (data
.passed_mode
== VOIDmode
|| DECL_SIZE (parm
) == NULL
)
3155 /* Update info on where next arg arrives in registers. */
3156 FUNCTION_ARG_ADVANCE (all
.args_so_far
, data
.promoted_mode
,
3157 data
.passed_type
, data
.named_arg
);
3159 /* ??? Once upon a time variable_size stuffed parameter list
3160 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3161 turned out to be less than manageable in the gimple world.
3162 Now we have to hunt them down ourselves. */
3163 walk_tree_without_duplicates (&data
.passed_type
,
3164 gimplify_parm_type
, &stmts
);
3166 if (!TREE_CONSTANT (DECL_SIZE (parm
)))
3168 gimplify_one_sizepos (&DECL_SIZE (parm
), &stmts
);
3169 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm
), &stmts
);
3172 if (data
.passed_pointer
)
3174 tree type
= TREE_TYPE (data
.passed_type
);
3175 if (reference_callee_copied (&all
.args_so_far
, TYPE_MODE (type
),
3176 type
, data
.named_arg
))
3180 /* For constant sized objects, this is trivial; for
3181 variable-sized objects, we have to play games. */
3182 if (TREE_CONSTANT (DECL_SIZE (parm
)))
3184 local
= create_tmp_var (type
, get_name (parm
));
3185 DECL_IGNORED_P (local
) = 0;
3189 tree ptr_type
, addr
;
3191 ptr_type
= build_pointer_type (type
);
3192 addr
= create_tmp_var (ptr_type
, get_name (parm
));
3193 DECL_IGNORED_P (addr
) = 0;
3194 local
= build_fold_indirect_ref (addr
);
3196 t
= built_in_decls
[BUILT_IN_ALLOCA
];
3197 t
= build_call_expr (t
, 1, DECL_SIZE_UNIT (parm
));
3198 t
= fold_convert (ptr_type
, t
);
3199 t
= build_gimple_modify_stmt (addr
, t
);
3200 gimplify_and_add (t
, &stmts
);
3203 t
= build_gimple_modify_stmt (local
, parm
);
3204 gimplify_and_add (t
, &stmts
);
3206 SET_DECL_VALUE_EXPR (parm
, local
);
3207 DECL_HAS_VALUE_EXPR_P (parm
) = 1;
3215 /* Compute the size and offset from the start of the stacked arguments for a
3216 parm passed in mode PASSED_MODE and with type TYPE.
3218 INITIAL_OFFSET_PTR points to the current offset into the stacked
3221 The starting offset and size for this parm are returned in
3222 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3223 nonzero, the offset is that of stack slot, which is returned in
3224 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3225 padding required from the initial offset ptr to the stack slot.
3227 IN_REGS is nonzero if the argument will be passed in registers. It will
3228 never be set if REG_PARM_STACK_SPACE is not defined.
3230 FNDECL is the function in which the argument was defined.
3232 There are two types of rounding that are done. The first, controlled by
3233 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
3234 list to be aligned to the specific boundary (in bits). This rounding
3235 affects the initial and starting offsets, but not the argument size.
3237 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3238 optionally rounds the size of the parm to PARM_BOUNDARY. The
3239 initial offset is not affected by this rounding, while the size always
3240 is and the starting offset may be. */
3242 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3243 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3244 callers pass in the total size of args so far as
3245 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
3248 locate_and_pad_parm (enum machine_mode passed_mode
, tree type
, int in_regs
,
3249 int partial
, tree fndecl ATTRIBUTE_UNUSED
,
3250 struct args_size
*initial_offset_ptr
,
3251 struct locate_and_pad_arg_data
*locate
)
3254 enum direction where_pad
;
3255 unsigned int boundary
;
3256 int reg_parm_stack_space
= 0;
3257 int part_size_in_regs
;
3259 #ifdef REG_PARM_STACK_SPACE
3260 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
3262 /* If we have found a stack parm before we reach the end of the
3263 area reserved for registers, skip that area. */
3266 if (reg_parm_stack_space
> 0)
3268 if (initial_offset_ptr
->var
)
3270 initial_offset_ptr
->var
3271 = size_binop (MAX_EXPR
, ARGS_SIZE_TREE (*initial_offset_ptr
),
3272 ssize_int (reg_parm_stack_space
));
3273 initial_offset_ptr
->constant
= 0;
3275 else if (initial_offset_ptr
->constant
< reg_parm_stack_space
)
3276 initial_offset_ptr
->constant
= reg_parm_stack_space
;
3279 #endif /* REG_PARM_STACK_SPACE */
3281 part_size_in_regs
= (reg_parm_stack_space
== 0 ? partial
: 0);
3284 = type
? size_in_bytes (type
) : size_int (GET_MODE_SIZE (passed_mode
));
3285 where_pad
= FUNCTION_ARG_PADDING (passed_mode
, type
);
3286 boundary
= FUNCTION_ARG_BOUNDARY (passed_mode
, type
);
3287 locate
->where_pad
= where_pad
;
3288 locate
->boundary
= boundary
;
3290 /* Remember if the outgoing parameter requires extra alignment on the
3291 calling function side. */
3292 if (boundary
> PREFERRED_STACK_BOUNDARY
)
3293 boundary
= PREFERRED_STACK_BOUNDARY
;
3294 if (cfun
->stack_alignment_needed
< boundary
)
3295 cfun
->stack_alignment_needed
= boundary
;
3297 #ifdef ARGS_GROW_DOWNWARD
3298 locate
->slot_offset
.constant
= -initial_offset_ptr
->constant
;
3299 if (initial_offset_ptr
->var
)
3300 locate
->slot_offset
.var
= size_binop (MINUS_EXPR
, ssize_int (0),
3301 initial_offset_ptr
->var
);
3305 if (where_pad
!= none
3306 && (!host_integerp (sizetree
, 1)
3307 || (tree_low_cst (sizetree
, 1) * BITS_PER_UNIT
) % PARM_BOUNDARY
))
3308 s2
= round_up (s2
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3309 SUB_PARM_SIZE (locate
->slot_offset
, s2
);
3312 locate
->slot_offset
.constant
+= part_size_in_regs
;
3315 #ifdef REG_PARM_STACK_SPACE
3316 || REG_PARM_STACK_SPACE (fndecl
) > 0
3319 pad_to_arg_alignment (&locate
->slot_offset
, boundary
,
3320 &locate
->alignment_pad
);
3322 locate
->size
.constant
= (-initial_offset_ptr
->constant
3323 - locate
->slot_offset
.constant
);
3324 if (initial_offset_ptr
->var
)
3325 locate
->size
.var
= size_binop (MINUS_EXPR
,
3326 size_binop (MINUS_EXPR
,
3328 initial_offset_ptr
->var
),
3329 locate
->slot_offset
.var
);
3331 /* Pad_below needs the pre-rounded size to know how much to pad
3333 locate
->offset
= locate
->slot_offset
;
3334 if (where_pad
== downward
)
3335 pad_below (&locate
->offset
, passed_mode
, sizetree
);
3337 #else /* !ARGS_GROW_DOWNWARD */
3339 #ifdef REG_PARM_STACK_SPACE
3340 || REG_PARM_STACK_SPACE (fndecl
) > 0
3343 pad_to_arg_alignment (initial_offset_ptr
, boundary
,
3344 &locate
->alignment_pad
);
3345 locate
->slot_offset
= *initial_offset_ptr
;
3347 #ifdef PUSH_ROUNDING
3348 if (passed_mode
!= BLKmode
)
3349 sizetree
= size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree
)));
3352 /* Pad_below needs the pre-rounded size to know how much to pad below
3353 so this must be done before rounding up. */
3354 locate
->offset
= locate
->slot_offset
;
3355 if (where_pad
== downward
)
3356 pad_below (&locate
->offset
, passed_mode
, sizetree
);
3358 if (where_pad
!= none
3359 && (!host_integerp (sizetree
, 1)
3360 || (tree_low_cst (sizetree
, 1) * BITS_PER_UNIT
) % PARM_BOUNDARY
))
3361 sizetree
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3363 ADD_PARM_SIZE (locate
->size
, sizetree
);
3365 locate
->size
.constant
-= part_size_in_regs
;
3366 #endif /* ARGS_GROW_DOWNWARD */
3369 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
3370 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
3373 pad_to_arg_alignment (struct args_size
*offset_ptr
, int boundary
,
3374 struct args_size
*alignment_pad
)
3376 tree save_var
= NULL_TREE
;
3377 HOST_WIDE_INT save_constant
= 0;
3378 int boundary_in_bytes
= boundary
/ BITS_PER_UNIT
;
3379 HOST_WIDE_INT sp_offset
= STACK_POINTER_OFFSET
;
3381 #ifdef SPARC_STACK_BOUNDARY_HACK
3382 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
3383 the real alignment of %sp. However, when it does this, the
3384 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
3385 if (SPARC_STACK_BOUNDARY_HACK
)
3389 if (boundary
> PARM_BOUNDARY
)
3391 save_var
= offset_ptr
->var
;
3392 save_constant
= offset_ptr
->constant
;
3395 alignment_pad
->var
= NULL_TREE
;
3396 alignment_pad
->constant
= 0;
3398 if (boundary
> BITS_PER_UNIT
)
3400 if (offset_ptr
->var
)
3402 tree sp_offset_tree
= ssize_int (sp_offset
);
3403 tree offset
= size_binop (PLUS_EXPR
,
3404 ARGS_SIZE_TREE (*offset_ptr
),
3406 #ifdef ARGS_GROW_DOWNWARD
3407 tree rounded
= round_down (offset
, boundary
/ BITS_PER_UNIT
);
3409 tree rounded
= round_up (offset
, boundary
/ BITS_PER_UNIT
);
3412 offset_ptr
->var
= size_binop (MINUS_EXPR
, rounded
, sp_offset_tree
);
3413 /* ARGS_SIZE_TREE includes constant term. */
3414 offset_ptr
->constant
= 0;
3415 if (boundary
> PARM_BOUNDARY
)
3416 alignment_pad
->var
= size_binop (MINUS_EXPR
, offset_ptr
->var
,
3421 offset_ptr
->constant
= -sp_offset
+
3422 #ifdef ARGS_GROW_DOWNWARD
3423 FLOOR_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
3425 CEIL_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
3427 if (boundary
> PARM_BOUNDARY
)
3428 alignment_pad
->constant
= offset_ptr
->constant
- save_constant
;
3434 pad_below (struct args_size
*offset_ptr
, enum machine_mode passed_mode
, tree sizetree
)
3436 if (passed_mode
!= BLKmode
)
3438 if (GET_MODE_BITSIZE (passed_mode
) % PARM_BOUNDARY
)
3439 offset_ptr
->constant
3440 += (((GET_MODE_BITSIZE (passed_mode
) + PARM_BOUNDARY
- 1)
3441 / PARM_BOUNDARY
* PARM_BOUNDARY
/ BITS_PER_UNIT
)
3442 - GET_MODE_SIZE (passed_mode
));
3446 if (TREE_CODE (sizetree
) != INTEGER_CST
3447 || (TREE_INT_CST_LOW (sizetree
) * BITS_PER_UNIT
) % PARM_BOUNDARY
)
3449 /* Round the size up to multiple of PARM_BOUNDARY bits. */
3450 tree s2
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3452 ADD_PARM_SIZE (*offset_ptr
, s2
);
3453 SUB_PARM_SIZE (*offset_ptr
, sizetree
);
3459 /* True if register REGNO was alive at a place where `setjmp' was
3460 called and was set more than once or is an argument. Such regs may
3461 be clobbered by `longjmp'. */
3464 regno_clobbered_at_setjmp (bitmap setjmp_crosses
, int regno
)
3466 /* There appear to be cases where some local vars never reach the
3467 backend but have bogus regnos. */
3468 if (regno
>= max_reg_num ())
3471 return ((REG_N_SETS (regno
) > 1
3472 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR
), regno
))
3473 && REGNO_REG_SET_P (setjmp_crosses
, regno
));
3476 /* Walk the tree of blocks describing the binding levels within a
3477 function and warn about variables the might be killed by setjmp or
3478 vfork. This is done after calling flow_analysis before register
3479 allocation since that will clobber the pseudo-regs to hard
3483 setjmp_vars_warning (bitmap setjmp_crosses
, tree block
)
3487 for (decl
= BLOCK_VARS (block
); decl
; decl
= TREE_CHAIN (decl
))
3489 if (TREE_CODE (decl
) == VAR_DECL
3490 && DECL_RTL_SET_P (decl
)
3491 && REG_P (DECL_RTL (decl
))
3492 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
3493 warning (OPT_Wclobbered
, "variable %q+D might be clobbered by"
3494 " %<longjmp%> or %<vfork%>", decl
);
3497 for (sub
= BLOCK_SUBBLOCKS (block
); sub
; sub
= BLOCK_CHAIN (sub
))
3498 setjmp_vars_warning (setjmp_crosses
, sub
);
3501 /* Do the appropriate part of setjmp_vars_warning
3502 but for arguments instead of local variables. */
3505 setjmp_args_warning (bitmap setjmp_crosses
)
3508 for (decl
= DECL_ARGUMENTS (current_function_decl
);
3509 decl
; decl
= TREE_CHAIN (decl
))
3510 if (DECL_RTL (decl
) != 0
3511 && REG_P (DECL_RTL (decl
))
3512 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
3513 warning (OPT_Wclobbered
,
3514 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
3518 /* Generate warning messages for variables live across setjmp. */
3521 generate_setjmp_warnings (void)
3523 bitmap setjmp_crosses
= regstat_get_setjmp_crosses ();
3525 if (n_basic_blocks
== NUM_FIXED_BLOCKS
3526 || bitmap_empty_p (setjmp_crosses
))
3529 setjmp_vars_warning (setjmp_crosses
, DECL_INITIAL (current_function_decl
));
3530 setjmp_args_warning (setjmp_crosses
);
3534 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
3535 and create duplicate blocks. */
3536 /* ??? Need an option to either create block fragments or to create
3537 abstract origin duplicates of a source block. It really depends
3538 on what optimization has been performed. */
3541 reorder_blocks (void)
3543 tree block
= DECL_INITIAL (current_function_decl
);
3544 VEC(tree
,heap
) *block_stack
;
3546 if (block
== NULL_TREE
)
3549 block_stack
= VEC_alloc (tree
, heap
, 10);
3551 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
3552 clear_block_marks (block
);
3554 /* Prune the old trees away, so that they don't get in the way. */
3555 BLOCK_SUBBLOCKS (block
) = NULL_TREE
;
3556 BLOCK_CHAIN (block
) = NULL_TREE
;
3558 /* Recreate the block tree from the note nesting. */
3559 reorder_blocks_1 (get_insns (), block
, &block_stack
);
3560 BLOCK_SUBBLOCKS (block
) = blocks_nreverse (BLOCK_SUBBLOCKS (block
));
3562 VEC_free (tree
, heap
, block_stack
);
3565 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
3568 clear_block_marks (tree block
)
3572 TREE_ASM_WRITTEN (block
) = 0;
3573 clear_block_marks (BLOCK_SUBBLOCKS (block
));
3574 block
= BLOCK_CHAIN (block
);
3579 reorder_blocks_1 (rtx insns
, tree current_block
, VEC(tree
,heap
) **p_block_stack
)
3583 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
3587 if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_BEG
)
3589 tree block
= NOTE_BLOCK (insn
);
3592 origin
= (BLOCK_FRAGMENT_ORIGIN (block
)
3593 ? BLOCK_FRAGMENT_ORIGIN (block
)
3596 /* If we have seen this block before, that means it now
3597 spans multiple address regions. Create a new fragment. */
3598 if (TREE_ASM_WRITTEN (block
))
3600 tree new_block
= copy_node (block
);
3602 BLOCK_FRAGMENT_ORIGIN (new_block
) = origin
;
3603 BLOCK_FRAGMENT_CHAIN (new_block
)
3604 = BLOCK_FRAGMENT_CHAIN (origin
);
3605 BLOCK_FRAGMENT_CHAIN (origin
) = new_block
;
3607 NOTE_BLOCK (insn
) = new_block
;
3611 BLOCK_SUBBLOCKS (block
) = 0;
3612 TREE_ASM_WRITTEN (block
) = 1;
3613 /* When there's only one block for the entire function,
3614 current_block == block and we mustn't do this, it
3615 will cause infinite recursion. */
3616 if (block
!= current_block
)
3618 if (block
!= origin
)
3619 gcc_assert (BLOCK_SUPERCONTEXT (origin
) == current_block
);
3621 BLOCK_SUPERCONTEXT (block
) = current_block
;
3622 BLOCK_CHAIN (block
) = BLOCK_SUBBLOCKS (current_block
);
3623 BLOCK_SUBBLOCKS (current_block
) = block
;
3624 current_block
= origin
;
3626 VEC_safe_push (tree
, heap
, *p_block_stack
, block
);
3628 else if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_END
)
3630 NOTE_BLOCK (insn
) = VEC_pop (tree
, *p_block_stack
);
3631 BLOCK_SUBBLOCKS (current_block
)
3632 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block
));
3633 current_block
= BLOCK_SUPERCONTEXT (current_block
);
3639 /* Reverse the order of elements in the chain T of blocks,
3640 and return the new head of the chain (old last element). */
3643 blocks_nreverse (tree t
)
3645 tree prev
= 0, decl
, next
;
3646 for (decl
= t
; decl
; decl
= next
)
3648 next
= BLOCK_CHAIN (decl
);
3649 BLOCK_CHAIN (decl
) = prev
;
3655 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
3656 non-NULL, list them all into VECTOR, in a depth-first preorder
3657 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
3661 all_blocks (tree block
, tree
*vector
)
3667 TREE_ASM_WRITTEN (block
) = 0;
3669 /* Record this block. */
3671 vector
[n_blocks
] = block
;
3675 /* Record the subblocks, and their subblocks... */
3676 n_blocks
+= all_blocks (BLOCK_SUBBLOCKS (block
),
3677 vector
? vector
+ n_blocks
: 0);
3678 block
= BLOCK_CHAIN (block
);
3684 /* Return a vector containing all the blocks rooted at BLOCK. The
3685 number of elements in the vector is stored in N_BLOCKS_P. The
3686 vector is dynamically allocated; it is the caller's responsibility
3687 to call `free' on the pointer returned. */
3690 get_block_vector (tree block
, int *n_blocks_p
)
3694 *n_blocks_p
= all_blocks (block
, NULL
);
3695 block_vector
= XNEWVEC (tree
, *n_blocks_p
);
3696 all_blocks (block
, block_vector
);
3698 return block_vector
;
3701 static GTY(()) int next_block_index
= 2;
3703 /* Set BLOCK_NUMBER for all the blocks in FN. */
3706 number_blocks (tree fn
)
3712 /* For SDB and XCOFF debugging output, we start numbering the blocks
3713 from 1 within each function, rather than keeping a running
3715 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
3716 if (write_symbols
== SDB_DEBUG
|| write_symbols
== XCOFF_DEBUG
)
3717 next_block_index
= 1;
3720 block_vector
= get_block_vector (DECL_INITIAL (fn
), &n_blocks
);
3722 /* The top-level BLOCK isn't numbered at all. */
3723 for (i
= 1; i
< n_blocks
; ++i
)
3724 /* We number the blocks from two. */
3725 BLOCK_NUMBER (block_vector
[i
]) = next_block_index
++;
3727 free (block_vector
);
3732 /* If VAR is present in a subblock of BLOCK, return the subblock. */
3735 debug_find_var_in_block_tree (tree var
, tree block
)
3739 for (t
= BLOCK_VARS (block
); t
; t
= TREE_CHAIN (t
))
3743 for (t
= BLOCK_SUBBLOCKS (block
); t
; t
= TREE_CHAIN (t
))
3745 tree ret
= debug_find_var_in_block_tree (var
, t
);
3753 /* Keep track of whether we're in a dummy function context. If we are,
3754 we don't want to invoke the set_current_function hook, because we'll
3755 get into trouble if the hook calls target_reinit () recursively or
3756 when the initial initialization is not yet complete. */
3758 static bool in_dummy_function
;
3760 /* Invoke the target hook when setting cfun. */
3763 invoke_set_current_function_hook (tree fndecl
)
3765 if (!in_dummy_function
)
3766 targetm
.set_current_function (fndecl
);
3769 /* cfun should never be set directly; use this function. */
3772 set_cfun (struct function
*new_cfun
)
3774 if (cfun
!= new_cfun
)
3777 invoke_set_current_function_hook (new_cfun
? new_cfun
->decl
: NULL_TREE
);
3781 /* Keep track of the cfun stack. */
3783 typedef struct function
*function_p
;
3785 DEF_VEC_P(function_p
);
3786 DEF_VEC_ALLOC_P(function_p
,heap
);
3788 /* Initialized with NOGC, making this poisonous to the garbage collector. */
3790 static VEC(function_p
,heap
) *cfun_stack
;
3792 /* We save the value of in_system_header here when pushing the first
3793 function on the cfun stack, and we restore it from here when
3794 popping the last function. */
3796 static bool saved_in_system_header
;
3798 /* Push the current cfun onto the stack, and set cfun to new_cfun. */
3801 push_cfun (struct function
*new_cfun
)
3804 saved_in_system_header
= in_system_header
;
3805 VEC_safe_push (function_p
, heap
, cfun_stack
, cfun
);
3807 in_system_header
= DECL_IN_SYSTEM_HEADER (new_cfun
->decl
);
3808 set_cfun (new_cfun
);
3811 /* Pop cfun from the stack. */
3816 struct function
*new_cfun
= VEC_pop (function_p
, cfun_stack
);
3817 in_system_header
= ((new_cfun
== NULL
) ? saved_in_system_header
3818 : DECL_IN_SYSTEM_HEADER (new_cfun
->decl
));
3819 set_cfun (new_cfun
);
3822 /* Return value of funcdef and increase it. */
3824 get_next_funcdef_no (void)
3826 return funcdef_no
++;
3829 /* Allocate a function structure for FNDECL and set its contents
3830 to the defaults. Set cfun to the newly-allocated object.
3831 Some of the helper functions invoked during initialization assume
3832 that cfun has already been set. Therefore, assign the new object
3833 directly into cfun and invoke the back end hook explicitly at the
3834 very end, rather than initializing a temporary and calling set_cfun
3837 ABSTRACT_P is true if this is a function that will never be seen by
3838 the middle-end. Such functions are front-end concepts (like C++
3839 function templates) that do not correspond directly to functions
3840 placed in object files. */
3843 allocate_struct_function (tree fndecl
, bool abstract_p
)
3846 tree fntype
= fndecl
? TREE_TYPE (fndecl
) : NULL_TREE
;
3848 cfun
= ggc_alloc_cleared (sizeof (struct function
));
3850 cfun
->stack_alignment_needed
= STACK_BOUNDARY
;
3851 cfun
->preferred_stack_boundary
= STACK_BOUNDARY
;
3853 current_function_funcdef_no
= get_next_funcdef_no ();
3855 cfun
->function_frequency
= FUNCTION_FREQUENCY_NORMAL
;
3857 init_eh_for_function ();
3859 if (init_machine_status
)
3860 cfun
->machine
= (*init_machine_status
) ();
3864 DECL_STRUCT_FUNCTION (fndecl
) = cfun
;
3865 cfun
->decl
= fndecl
;
3867 result
= DECL_RESULT (fndecl
);
3868 if (!abstract_p
&& aggregate_value_p (result
, fndecl
))
3870 #ifdef PCC_STATIC_STRUCT_RETURN
3871 current_function_returns_pcc_struct
= 1;
3873 current_function_returns_struct
= 1;
3876 current_function_stdarg
3878 && TYPE_ARG_TYPES (fntype
) != 0
3879 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype
)))
3880 != void_type_node
));
3882 /* Assume all registers in stdarg functions need to be saved. */
3883 cfun
->va_list_gpr_size
= VA_LIST_MAX_GPR_SIZE
;
3884 cfun
->va_list_fpr_size
= VA_LIST_MAX_FPR_SIZE
;
3887 invoke_set_current_function_hook (fndecl
);
3890 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
3891 instead of just setting it. */
3894 push_struct_function (tree fndecl
)
3897 saved_in_system_header
= in_system_header
;
3898 VEC_safe_push (function_p
, heap
, cfun_stack
, cfun
);
3900 in_system_header
= DECL_IN_SYSTEM_HEADER (fndecl
);
3901 allocate_struct_function (fndecl
, false);
3904 /* Reset cfun, and other non-struct-function variables to defaults as
3905 appropriate for emitting rtl at the start of a function. */
3908 prepare_function_start (void)
3910 gcc_assert (!rtl
.emit
.x_last_insn
);
3912 init_varasm_status ();
3915 cse_not_expected
= ! optimize
;
3917 /* Caller save not needed yet. */
3918 caller_save_needed
= 0;
3920 /* We haven't done register allocation yet. */
3923 /* Indicate that we have not instantiated virtual registers yet. */
3924 virtuals_instantiated
= 0;
3926 /* Indicate that we want CONCATs now. */
3927 generating_concat_p
= 1;
3929 /* Indicate we have no need of a frame pointer yet. */
3930 frame_pointer_needed
= 0;
3933 /* Initialize the rtl expansion mechanism so that we can do simple things
3934 like generate sequences. This is used to provide a context during global
3935 initialization of some passes. You must call expand_dummy_function_end
3936 to exit this context. */
3939 init_dummy_function_start (void)
3941 gcc_assert (!in_dummy_function
);
3942 in_dummy_function
= true;
3943 push_struct_function (NULL_TREE
);
3944 prepare_function_start ();
3947 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
3948 and initialize static variables for generating RTL for the statements
3952 init_function_start (tree subr
)
3954 if (subr
&& DECL_STRUCT_FUNCTION (subr
))
3955 set_cfun (DECL_STRUCT_FUNCTION (subr
));
3957 allocate_struct_function (subr
, false);
3958 prepare_function_start ();
3960 /* Warn if this value is an aggregate type,
3961 regardless of which calling convention we are using for it. */
3962 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr
))))
3963 warning (OPT_Waggregate_return
, "function returns an aggregate");
3966 /* Make sure all values used by the optimization passes have sane
3969 init_function_for_compilation (void)
3973 /* No prologue/epilogue insns yet. Make sure that these vectors are
3975 gcc_assert (VEC_length (int, prologue
) == 0);
3976 gcc_assert (VEC_length (int, epilogue
) == 0);
3977 gcc_assert (VEC_length (int, sibcall_epilogue
) == 0);
3981 struct rtl_opt_pass pass_init_function
=
3987 init_function_for_compilation
, /* execute */
3990 0, /* static_pass_number */
3992 0, /* properties_required */
3993 0, /* properties_provided */
3994 0, /* properties_destroyed */
3995 0, /* todo_flags_start */
3996 0 /* todo_flags_finish */
4002 expand_main_function (void)
4004 #if (defined(INVOKE__main) \
4005 || (!defined(HAS_INIT_SECTION) \
4006 && !defined(INIT_SECTION_ASM_OP) \
4007 && !defined(INIT_ARRAY_SECTION_ASM_OP)))
4008 emit_library_call (init_one_libfunc (NAME__MAIN
), LCT_NORMAL
, VOIDmode
, 0);
4012 /* Expand code to initialize the stack_protect_guard. This is invoked at
4013 the beginning of a function to be protected. */
4015 #ifndef HAVE_stack_protect_set
4016 # define HAVE_stack_protect_set 0
4017 # define gen_stack_protect_set(x,y) (gcc_unreachable (), NULL_RTX)
4021 stack_protect_prologue (void)
4023 tree guard_decl
= targetm
.stack_protect_guard ();
4026 /* Avoid expand_expr here, because we don't want guard_decl pulled
4027 into registers unless absolutely necessary. And we know that
4028 cfun->stack_protect_guard is a local stack slot, so this skips
4030 x
= validize_mem (DECL_RTL (cfun
->stack_protect_guard
));
4031 y
= validize_mem (DECL_RTL (guard_decl
));
4033 /* Allow the target to copy from Y to X without leaking Y into a
4035 if (HAVE_stack_protect_set
)
4037 rtx insn
= gen_stack_protect_set (x
, y
);
4045 /* Otherwise do a straight move. */
4046 emit_move_insn (x
, y
);
4049 /* Expand code to verify the stack_protect_guard. This is invoked at
4050 the end of a function to be protected. */
4052 #ifndef HAVE_stack_protect_test
4053 # define HAVE_stack_protect_test 0
4054 # define gen_stack_protect_test(x, y, z) (gcc_unreachable (), NULL_RTX)
4058 stack_protect_epilogue (void)
4060 tree guard_decl
= targetm
.stack_protect_guard ();
4061 rtx label
= gen_label_rtx ();
4064 /* Avoid expand_expr here, because we don't want guard_decl pulled
4065 into registers unless absolutely necessary. And we know that
4066 cfun->stack_protect_guard is a local stack slot, so this skips
4068 x
= validize_mem (DECL_RTL (cfun
->stack_protect_guard
));
4069 y
= validize_mem (DECL_RTL (guard_decl
));
4071 /* Allow the target to compare Y with X without leaking either into
4073 switch (HAVE_stack_protect_test
!= 0)
4076 tmp
= gen_stack_protect_test (x
, y
, label
);
4085 emit_cmp_and_jump_insns (x
, y
, EQ
, NULL_RTX
, ptr_mode
, 1, label
);
4089 /* The noreturn predictor has been moved to the tree level. The rtl-level
4090 predictors estimate this branch about 20%, which isn't enough to get
4091 things moved out of line. Since this is the only extant case of adding
4092 a noreturn function at the rtl level, it doesn't seem worth doing ought
4093 except adding the prediction by hand. */
4094 tmp
= get_last_insn ();
4096 predict_insn_def (tmp
, PRED_NORETURN
, TAKEN
);
4098 expand_expr_stmt (targetm
.stack_protect_fail ());
4102 /* Start the RTL for a new function, and set variables used for
4104 SUBR is the FUNCTION_DECL node.
4105 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4106 the function's parameters, which must be run at any return statement. */
4109 expand_function_start (tree subr
)
4111 /* Make sure volatile mem refs aren't considered
4112 valid operands of arithmetic insns. */
4113 init_recog_no_volatile ();
4115 current_function_profile
4117 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr
));
4119 current_function_limit_stack
4120 = (stack_limit_rtx
!= NULL_RTX
&& ! DECL_NO_LIMIT_STACK (subr
));
4122 /* Make the label for return statements to jump to. Do not special
4123 case machines with special return instructions -- they will be
4124 handled later during jump, ifcvt, or epilogue creation. */
4125 return_label
= gen_label_rtx ();
4127 /* Initialize rtx used to return the value. */
4128 /* Do this before assign_parms so that we copy the struct value address
4129 before any library calls that assign parms might generate. */
4131 /* Decide whether to return the value in memory or in a register. */
4132 if (aggregate_value_p (DECL_RESULT (subr
), subr
))
4134 /* Returning something that won't go in a register. */
4135 rtx value_address
= 0;
4137 #ifdef PCC_STATIC_STRUCT_RETURN
4138 if (current_function_returns_pcc_struct
)
4140 int size
= int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr
)));
4141 value_address
= assemble_static_space (size
);
4146 rtx sv
= targetm
.calls
.struct_value_rtx (TREE_TYPE (subr
), 2);
4147 /* Expect to be passed the address of a place to store the value.
4148 If it is passed as an argument, assign_parms will take care of
4152 value_address
= gen_reg_rtx (Pmode
);
4153 emit_move_insn (value_address
, sv
);
4158 rtx x
= value_address
;
4159 if (!DECL_BY_REFERENCE (DECL_RESULT (subr
)))
4161 x
= gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr
)), x
);
4162 set_mem_attributes (x
, DECL_RESULT (subr
), 1);
4164 SET_DECL_RTL (DECL_RESULT (subr
), x
);
4167 else if (DECL_MODE (DECL_RESULT (subr
)) == VOIDmode
)
4168 /* If return mode is void, this decl rtl should not be used. */
4169 SET_DECL_RTL (DECL_RESULT (subr
), NULL_RTX
);
4172 /* Compute the return values into a pseudo reg, which we will copy
4173 into the true return register after the cleanups are done. */
4174 tree return_type
= TREE_TYPE (DECL_RESULT (subr
));
4175 if (TYPE_MODE (return_type
) != BLKmode
4176 && targetm
.calls
.return_in_msb (return_type
))
4177 /* expand_function_end will insert the appropriate padding in
4178 this case. Use the return value's natural (unpadded) mode
4179 within the function proper. */
4180 SET_DECL_RTL (DECL_RESULT (subr
),
4181 gen_reg_rtx (TYPE_MODE (return_type
)));
4184 /* In order to figure out what mode to use for the pseudo, we
4185 figure out what the mode of the eventual return register will
4186 actually be, and use that. */
4187 rtx hard_reg
= hard_function_value (return_type
, subr
, 0, 1);
4189 /* Structures that are returned in registers are not
4190 aggregate_value_p, so we may see a PARALLEL or a REG. */
4191 if (REG_P (hard_reg
))
4192 SET_DECL_RTL (DECL_RESULT (subr
),
4193 gen_reg_rtx (GET_MODE (hard_reg
)));
4196 gcc_assert (GET_CODE (hard_reg
) == PARALLEL
);
4197 SET_DECL_RTL (DECL_RESULT (subr
), gen_group_rtx (hard_reg
));
4201 /* Set DECL_REGISTER flag so that expand_function_end will copy the
4202 result to the real return register(s). */
4203 DECL_REGISTER (DECL_RESULT (subr
)) = 1;
4206 /* Initialize rtx for parameters and local variables.
4207 In some cases this requires emitting insns. */
4208 assign_parms (subr
);
4210 /* If function gets a static chain arg, store it. */
4211 if (cfun
->static_chain_decl
)
4213 tree parm
= cfun
->static_chain_decl
;
4214 rtx local
= gen_reg_rtx (Pmode
);
4216 set_decl_incoming_rtl (parm
, static_chain_incoming_rtx
, false);
4217 SET_DECL_RTL (parm
, local
);
4218 mark_reg_pointer (local
, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
4220 emit_move_insn (local
, static_chain_incoming_rtx
);
4223 /* If the function receives a non-local goto, then store the
4224 bits we need to restore the frame pointer. */
4225 if (cfun
->nonlocal_goto_save_area
)
4230 /* ??? We need to do this save early. Unfortunately here is
4231 before the frame variable gets declared. Help out... */
4232 tree var
= TREE_OPERAND (cfun
->nonlocal_goto_save_area
, 0);
4233 if (!DECL_RTL_SET_P (var
))
4236 t_save
= build4 (ARRAY_REF
, ptr_type_node
,
4237 cfun
->nonlocal_goto_save_area
,
4238 integer_zero_node
, NULL_TREE
, NULL_TREE
);
4239 r_save
= expand_expr (t_save
, NULL_RTX
, VOIDmode
, EXPAND_WRITE
);
4240 r_save
= convert_memory_address (Pmode
, r_save
);
4242 emit_move_insn (r_save
, virtual_stack_vars_rtx
);
4243 update_nonlocal_goto_save_area ();
4246 /* The following was moved from init_function_start.
4247 The move is supposed to make sdb output more accurate. */
4248 /* Indicate the beginning of the function body,
4249 as opposed to parm setup. */
4250 emit_note (NOTE_INSN_FUNCTION_BEG
);
4252 gcc_assert (NOTE_P (get_last_insn ()));
4254 parm_birth_insn
= get_last_insn ();
4256 if (current_function_profile
)
4259 PROFILE_HOOK (current_function_funcdef_no
);
4263 /* After the display initializations is where the stack checking
4265 if(flag_stack_check
)
4266 stack_check_probe_note
= emit_note (NOTE_INSN_DELETED
);
4268 /* Make sure there is a line number after the function entry setup code. */
4269 force_next_line_note ();
4272 /* Undo the effects of init_dummy_function_start. */
4274 expand_dummy_function_end (void)
4276 gcc_assert (in_dummy_function
);
4278 /* End any sequences that failed to be closed due to syntax errors. */
4279 while (in_sequence_p ())
4282 /* Outside function body, can't compute type's actual size
4283 until next function's body starts. */
4285 free_after_parsing (cfun
);
4286 free_after_compilation (cfun
);
4288 in_dummy_function
= false;
4291 /* Call DOIT for each hard register used as a return value from
4292 the current function. */
4295 diddle_return_value (void (*doit
) (rtx
, void *), void *arg
)
4297 rtx outgoing
= current_function_return_rtx
;
4302 if (REG_P (outgoing
))
4303 (*doit
) (outgoing
, arg
);
4304 else if (GET_CODE (outgoing
) == PARALLEL
)
4308 for (i
= 0; i
< XVECLEN (outgoing
, 0); i
++)
4310 rtx x
= XEXP (XVECEXP (outgoing
, 0, i
), 0);
4312 if (REG_P (x
) && REGNO (x
) < FIRST_PSEUDO_REGISTER
)
4319 do_clobber_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
4321 emit_insn (gen_rtx_CLOBBER (VOIDmode
, reg
));
4325 clobber_return_register (void)
4327 diddle_return_value (do_clobber_return_reg
, NULL
);
4329 /* In case we do use pseudo to return value, clobber it too. */
4330 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
4332 tree decl_result
= DECL_RESULT (current_function_decl
);
4333 rtx decl_rtl
= DECL_RTL (decl_result
);
4334 if (REG_P (decl_rtl
) && REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
)
4336 do_clobber_return_reg (decl_rtl
, NULL
);
4342 do_use_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
4344 emit_insn (gen_rtx_USE (VOIDmode
, reg
));
4348 use_return_register (void)
4350 diddle_return_value (do_use_return_reg
, NULL
);
4353 /* Possibly warn about unused parameters. */
4355 do_warn_unused_parameter (tree fn
)
4359 for (decl
= DECL_ARGUMENTS (fn
);
4360 decl
; decl
= TREE_CHAIN (decl
))
4361 if (!TREE_USED (decl
) && TREE_CODE (decl
) == PARM_DECL
4362 && DECL_NAME (decl
) && !DECL_ARTIFICIAL (decl
)
4363 && !TREE_NO_WARNING (decl
))
4364 warning (OPT_Wunused_parameter
, "unused parameter %q+D", decl
);
4367 static GTY(()) rtx initial_trampoline
;
4369 /* Generate RTL for the end of the current function. */
4372 expand_function_end (void)
4376 /* If arg_pointer_save_area was referenced only from a nested
4377 function, we will not have initialized it yet. Do that now. */
4378 if (arg_pointer_save_area
&& ! cfun
->arg_pointer_save_area_init
)
4379 get_arg_pointer_save_area ();
4381 /* If we are doing stack checking and this function makes calls,
4382 do a stack probe at the start of the function to ensure we have enough
4383 space for another stack frame. */
4384 if (flag_stack_check
&& ! STACK_CHECK_BUILTIN
)
4388 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
4392 probe_stack_range (STACK_CHECK_PROTECT
,
4393 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE
));
4396 emit_insn_before (seq
, stack_check_probe_note
);
4401 /* End any sequences that failed to be closed due to syntax errors. */
4402 while (in_sequence_p ())
4405 clear_pending_stack_adjust ();
4406 do_pending_stack_adjust ();
4408 /* Output a linenumber for the end of the function.
4409 SDB depends on this. */
4410 force_next_line_note ();
4411 set_curr_insn_source_location (input_location
);
4413 /* Before the return label (if any), clobber the return
4414 registers so that they are not propagated live to the rest of
4415 the function. This can only happen with functions that drop
4416 through; if there had been a return statement, there would
4417 have either been a return rtx, or a jump to the return label.
4419 We delay actual code generation after the current_function_value_rtx
4421 clobber_after
= get_last_insn ();
4423 /* Output the label for the actual return from the function. */
4424 emit_label (return_label
);
4426 if (USING_SJLJ_EXCEPTIONS
)
4428 /* Let except.c know where it should emit the call to unregister
4429 the function context for sjlj exceptions. */
4430 if (flag_exceptions
)
4431 sjlj_emit_function_exit_after (get_last_insn ());
4435 /* We want to ensure that instructions that may trap are not
4436 moved into the epilogue by scheduling, because we don't
4437 always emit unwind information for the epilogue. */
4438 if (flag_non_call_exceptions
)
4439 emit_insn (gen_blockage ());
4442 /* If this is an implementation of throw, do what's necessary to
4443 communicate between __builtin_eh_return and the epilogue. */
4444 expand_eh_return ();
4446 /* If scalar return value was computed in a pseudo-reg, or was a named
4447 return value that got dumped to the stack, copy that to the hard
4449 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
4451 tree decl_result
= DECL_RESULT (current_function_decl
);
4452 rtx decl_rtl
= DECL_RTL (decl_result
);
4454 if (REG_P (decl_rtl
)
4455 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
4456 : DECL_REGISTER (decl_result
))
4458 rtx real_decl_rtl
= current_function_return_rtx
;
4460 /* This should be set in assign_parms. */
4461 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl
));
4463 /* If this is a BLKmode structure being returned in registers,
4464 then use the mode computed in expand_return. Note that if
4465 decl_rtl is memory, then its mode may have been changed,
4466 but that current_function_return_rtx has not. */
4467 if (GET_MODE (real_decl_rtl
) == BLKmode
)
4468 PUT_MODE (real_decl_rtl
, GET_MODE (decl_rtl
));
4470 /* If a non-BLKmode return value should be padded at the least
4471 significant end of the register, shift it left by the appropriate
4472 amount. BLKmode results are handled using the group load/store
4474 if (TYPE_MODE (TREE_TYPE (decl_result
)) != BLKmode
4475 && targetm
.calls
.return_in_msb (TREE_TYPE (decl_result
)))
4477 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl
),
4478 REGNO (real_decl_rtl
)),
4480 shift_return_value (GET_MODE (decl_rtl
), true, real_decl_rtl
);
4482 /* If a named return value dumped decl_return to memory, then
4483 we may need to re-do the PROMOTE_MODE signed/unsigned
4485 else if (GET_MODE (real_decl_rtl
) != GET_MODE (decl_rtl
))
4487 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (decl_result
));
4489 if (targetm
.calls
.promote_function_return (TREE_TYPE (current_function_decl
)))
4490 promote_mode (TREE_TYPE (decl_result
), GET_MODE (decl_rtl
),
4493 convert_move (real_decl_rtl
, decl_rtl
, unsignedp
);
4495 else if (GET_CODE (real_decl_rtl
) == PARALLEL
)
4497 /* If expand_function_start has created a PARALLEL for decl_rtl,
4498 move the result to the real return registers. Otherwise, do
4499 a group load from decl_rtl for a named return. */
4500 if (GET_CODE (decl_rtl
) == PARALLEL
)
4501 emit_group_move (real_decl_rtl
, decl_rtl
);
4503 emit_group_load (real_decl_rtl
, decl_rtl
,
4504 TREE_TYPE (decl_result
),
4505 int_size_in_bytes (TREE_TYPE (decl_result
)));
4507 /* In the case of complex integer modes smaller than a word, we'll
4508 need to generate some non-trivial bitfield insertions. Do that
4509 on a pseudo and not the hard register. */
4510 else if (GET_CODE (decl_rtl
) == CONCAT
4511 && GET_MODE_CLASS (GET_MODE (decl_rtl
)) == MODE_COMPLEX_INT
4512 && GET_MODE_BITSIZE (GET_MODE (decl_rtl
)) <= BITS_PER_WORD
)
4514 int old_generating_concat_p
;
4517 old_generating_concat_p
= generating_concat_p
;
4518 generating_concat_p
= 0;
4519 tmp
= gen_reg_rtx (GET_MODE (decl_rtl
));
4520 generating_concat_p
= old_generating_concat_p
;
4522 emit_move_insn (tmp
, decl_rtl
);
4523 emit_move_insn (real_decl_rtl
, tmp
);
4526 emit_move_insn (real_decl_rtl
, decl_rtl
);
4530 /* If returning a structure, arrange to return the address of the value
4531 in a place where debuggers expect to find it.
4533 If returning a structure PCC style,
4534 the caller also depends on this value.
4535 And current_function_returns_pcc_struct is not necessarily set. */
4536 if (current_function_returns_struct
4537 || current_function_returns_pcc_struct
)
4539 rtx value_address
= DECL_RTL (DECL_RESULT (current_function_decl
));
4540 tree type
= TREE_TYPE (DECL_RESULT (current_function_decl
));
4543 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl
)))
4544 type
= TREE_TYPE (type
);
4546 value_address
= XEXP (value_address
, 0);
4548 outgoing
= targetm
.calls
.function_value (build_pointer_type (type
),
4549 current_function_decl
, true);
4551 /* Mark this as a function return value so integrate will delete the
4552 assignment and USE below when inlining this function. */
4553 REG_FUNCTION_VALUE_P (outgoing
) = 1;
4555 /* The address may be ptr_mode and OUTGOING may be Pmode. */
4556 value_address
= convert_memory_address (GET_MODE (outgoing
),
4559 emit_move_insn (outgoing
, value_address
);
4561 /* Show return register used to hold result (in this case the address
4563 current_function_return_rtx
= outgoing
;
4566 /* Emit the actual code to clobber return register. */
4571 clobber_return_register ();
4572 expand_naked_return ();
4576 emit_insn_after (seq
, clobber_after
);
4579 /* Output the label for the naked return from the function. */
4580 emit_label (naked_return_label
);
4582 /* @@@ This is a kludge. We want to ensure that instructions that
4583 may trap are not moved into the epilogue by scheduling, because
4584 we don't always emit unwind information for the epilogue. */
4585 if (! USING_SJLJ_EXCEPTIONS
&& flag_non_call_exceptions
)
4586 emit_insn (gen_blockage ());
4588 /* If stack protection is enabled for this function, check the guard. */
4589 if (cfun
->stack_protect_guard
)
4590 stack_protect_epilogue ();
4592 /* If we had calls to alloca, and this machine needs
4593 an accurate stack pointer to exit the function,
4594 insert some code to save and restore the stack pointer. */
4595 if (! EXIT_IGNORE_STACK
4596 && current_function_calls_alloca
)
4600 emit_stack_save (SAVE_FUNCTION
, &tem
, parm_birth_insn
);
4601 emit_stack_restore (SAVE_FUNCTION
, tem
, NULL_RTX
);
4604 /* ??? This should no longer be necessary since stupid is no longer with
4605 us, but there are some parts of the compiler (eg reload_combine, and
4606 sh mach_dep_reorg) that still try and compute their own lifetime info
4607 instead of using the general framework. */
4608 use_return_register ();
4612 get_arg_pointer_save_area (void)
4614 rtx ret
= arg_pointer_save_area
;
4618 ret
= assign_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0);
4619 arg_pointer_save_area
= ret
;
4622 if (! cfun
->arg_pointer_save_area_init
)
4626 /* Save the arg pointer at the beginning of the function. The
4627 generated stack slot may not be a valid memory address, so we
4628 have to check it and fix it if necessary. */
4630 emit_move_insn (validize_mem (ret
), virtual_incoming_args_rtx
);
4634 push_topmost_sequence ();
4635 emit_insn_after (seq
, entry_of_function ());
4636 pop_topmost_sequence ();
4642 /* Extend a vector that records the INSN_UIDs of INSNS
4643 (a list of one or more insns). */
4646 record_insns (rtx insns
, VEC(int,heap
) **vecp
)
4650 for (tmp
= insns
; tmp
!= NULL_RTX
; tmp
= NEXT_INSN (tmp
))
4651 VEC_safe_push (int, heap
, *vecp
, INSN_UID (tmp
));
4654 /* Set the locator of the insn chain starting at INSN to LOC. */
4656 set_insn_locators (rtx insn
, int loc
)
4658 while (insn
!= NULL_RTX
)
4661 INSN_LOCATOR (insn
) = loc
;
4662 insn
= NEXT_INSN (insn
);
4666 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
4667 be running after reorg, SEQUENCE rtl is possible. */
4670 contains (const_rtx insn
, VEC(int,heap
) **vec
)
4674 if (NONJUMP_INSN_P (insn
)
4675 && GET_CODE (PATTERN (insn
)) == SEQUENCE
)
4678 for (i
= XVECLEN (PATTERN (insn
), 0) - 1; i
>= 0; i
--)
4679 for (j
= VEC_length (int, *vec
) - 1; j
>= 0; --j
)
4680 if (INSN_UID (XVECEXP (PATTERN (insn
), 0, i
))
4681 == VEC_index (int, *vec
, j
))
4687 for (j
= VEC_length (int, *vec
) - 1; j
>= 0; --j
)
4688 if (INSN_UID (insn
) == VEC_index (int, *vec
, j
))
4695 prologue_epilogue_contains (const_rtx insn
)
4697 if (contains (insn
, &prologue
))
4699 if (contains (insn
, &epilogue
))
4705 sibcall_epilogue_contains (const_rtx insn
)
4707 if (sibcall_epilogue
)
4708 return contains (insn
, &sibcall_epilogue
);
4713 /* Insert gen_return at the end of block BB. This also means updating
4714 block_for_insn appropriately. */
4717 emit_return_into_block (basic_block bb
)
4719 emit_jump_insn_after (gen_return (), BB_END (bb
));
4721 #endif /* HAVE_return */
4723 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
4725 /* These functions convert the epilogue into a variant that does not
4726 modify the stack pointer. This is used in cases where a function
4727 returns an object whose size is not known until it is computed.
4728 The called function leaves the object on the stack, leaves the
4729 stack depressed, and returns a pointer to the object.
4731 What we need to do is track all modifications and references to the
4732 stack pointer, deleting the modifications and changing the
4733 references to point to the location the stack pointer would have
4734 pointed to had the modifications taken place.
4736 These functions need to be portable so we need to make as few
4737 assumptions about the epilogue as we can. However, the epilogue
4738 basically contains three things: instructions to reset the stack
4739 pointer, instructions to reload registers, possibly including the
4740 frame pointer, and an instruction to return to the caller.
4742 We must be sure of what a relevant epilogue insn is doing. We also
4743 make no attempt to validate the insns we make since if they are
4744 invalid, we probably can't do anything valid. The intent is that
4745 these routines get "smarter" as more and more machines start to use
4746 them and they try operating on different epilogues.
4748 We use the following structure to track what the part of the
4749 epilogue that we've already processed has done. We keep two copies
4750 of the SP equivalence, one for use during the insn we are
4751 processing and one for use in the next insn. The difference is
4752 because one part of a PARALLEL may adjust SP and the other may use
4757 rtx sp_equiv_reg
; /* REG that SP is set from, perhaps SP. */
4758 HOST_WIDE_INT sp_offset
; /* Offset from SP_EQUIV_REG of present SP. */
4759 rtx new_sp_equiv_reg
; /* REG to be used at end of insn. */
4760 HOST_WIDE_INT new_sp_offset
; /* Offset to be used at end of insn. */
4761 rtx equiv_reg_src
; /* If nonzero, the value that SP_EQUIV_REG
4762 should be set to once we no longer need
4764 rtx const_equiv
[FIRST_PSEUDO_REGISTER
]; /* Any known constant equivalences
4768 static void handle_epilogue_set (rtx
, struct epi_info
*);
4769 static void update_epilogue_consts (rtx
, const_rtx
, void *);
4770 static void emit_equiv_load (struct epi_info
*);
4772 /* Modify INSN, a list of one or more insns that is part of the epilogue, to
4773 no modifications to the stack pointer. Return the new list of insns. */
4776 keep_stack_depressed (rtx insns
)
4779 struct epi_info info
;
4782 /* If the epilogue is just a single instruction, it must be OK as is. */
4783 if (NEXT_INSN (insns
) == NULL_RTX
)
4786 /* Otherwise, start a sequence, initialize the information we have, and
4787 process all the insns we were given. */
4790 info
.sp_equiv_reg
= stack_pointer_rtx
;
4792 info
.equiv_reg_src
= 0;
4794 for (j
= 0; j
< FIRST_PSEUDO_REGISTER
; j
++)
4795 info
.const_equiv
[j
] = 0;
4799 while (insn
!= NULL_RTX
)
4801 next
= NEXT_INSN (insn
);
4810 /* If this insn references the register that SP is equivalent to and
4811 we have a pending load to that register, we must force out the load
4812 first and then indicate we no longer know what SP's equivalent is. */
4813 if (info
.equiv_reg_src
!= 0
4814 && reg_referenced_p (info
.sp_equiv_reg
, PATTERN (insn
)))
4816 emit_equiv_load (&info
);
4817 info
.sp_equiv_reg
= 0;
4820 info
.new_sp_equiv_reg
= info
.sp_equiv_reg
;
4821 info
.new_sp_offset
= info
.sp_offset
;
4823 /* If this is a (RETURN) and the return address is on the stack,
4824 update the address and change to an indirect jump. */
4825 if (GET_CODE (PATTERN (insn
)) == RETURN
4826 || (GET_CODE (PATTERN (insn
)) == PARALLEL
4827 && GET_CODE (XVECEXP (PATTERN (insn
), 0, 0)) == RETURN
))
4829 rtx retaddr
= INCOMING_RETURN_ADDR_RTX
;
4831 HOST_WIDE_INT offset
= 0;
4832 rtx jump_insn
, jump_set
;
4834 /* If the return address is in a register, we can emit the insn
4835 unchanged. Otherwise, it must be a MEM and we see what the
4836 base register and offset are. In any case, we have to emit any
4837 pending load to the equivalent reg of SP, if any. */
4838 if (REG_P (retaddr
))
4840 emit_equiv_load (&info
);
4848 gcc_assert (MEM_P (retaddr
));
4850 ret_ptr
= XEXP (retaddr
, 0);
4852 if (REG_P (ret_ptr
))
4854 base
= gen_rtx_REG (Pmode
, REGNO (ret_ptr
));
4859 gcc_assert (GET_CODE (ret_ptr
) == PLUS
4860 && REG_P (XEXP (ret_ptr
, 0))
4861 && GET_CODE (XEXP (ret_ptr
, 1)) == CONST_INT
);
4862 base
= gen_rtx_REG (Pmode
, REGNO (XEXP (ret_ptr
, 0)));
4863 offset
= INTVAL (XEXP (ret_ptr
, 1));
4867 /* If the base of the location containing the return pointer
4868 is SP, we must update it with the replacement address. Otherwise,
4869 just build the necessary MEM. */
4870 retaddr
= plus_constant (base
, offset
);
4871 if (base
== stack_pointer_rtx
)
4872 retaddr
= simplify_replace_rtx (retaddr
, stack_pointer_rtx
,
4873 plus_constant (info
.sp_equiv_reg
,
4876 retaddr
= gen_rtx_MEM (Pmode
, retaddr
);
4877 MEM_NOTRAP_P (retaddr
) = 1;
4879 /* If there is a pending load to the equivalent register for SP
4880 and we reference that register, we must load our address into
4881 a scratch register and then do that load. */
4882 if (info
.equiv_reg_src
4883 && reg_overlap_mentioned_p (info
.equiv_reg_src
, retaddr
))
4888 for (regno
= 0; regno
< FIRST_PSEUDO_REGISTER
; regno
++)
4889 if (HARD_REGNO_MODE_OK (regno
, Pmode
)
4890 && !fixed_regs
[regno
]
4891 && TEST_HARD_REG_BIT (regs_invalidated_by_call
, regno
)
4893 (DF_LR_IN (EXIT_BLOCK_PTR
), regno
)
4894 && !refers_to_regno_p (regno
,
4895 end_hard_regno (Pmode
, regno
),
4896 info
.equiv_reg_src
, NULL
)
4897 && info
.const_equiv
[regno
] == 0)
4900 gcc_assert (regno
< FIRST_PSEUDO_REGISTER
);
4902 reg
= gen_rtx_REG (Pmode
, regno
);
4903 emit_move_insn (reg
, retaddr
);
4907 emit_equiv_load (&info
);
4908 jump_insn
= emit_jump_insn (gen_indirect_jump (retaddr
));
4910 /* Show the SET in the above insn is a RETURN. */
4911 jump_set
= single_set (jump_insn
);
4912 gcc_assert (jump_set
);
4913 SET_IS_RETURN_P (jump_set
) = 1;
4916 /* If SP is not mentioned in the pattern and its equivalent register, if
4917 any, is not modified, just emit it. Otherwise, if neither is set,
4918 replace the reference to SP and emit the insn. If none of those are
4919 true, handle each SET individually. */
4920 else if (!reg_mentioned_p (stack_pointer_rtx
, PATTERN (insn
))
4921 && (info
.sp_equiv_reg
== stack_pointer_rtx
4922 || !reg_set_p (info
.sp_equiv_reg
, insn
)))
4924 else if (! reg_set_p (stack_pointer_rtx
, insn
)
4925 && (info
.sp_equiv_reg
== stack_pointer_rtx
4926 || !reg_set_p (info
.sp_equiv_reg
, insn
)))
4930 changed
= validate_replace_rtx (stack_pointer_rtx
,
4931 plus_constant (info
.sp_equiv_reg
,
4934 gcc_assert (changed
);
4938 else if (GET_CODE (PATTERN (insn
)) == SET
)
4939 handle_epilogue_set (PATTERN (insn
), &info
);
4940 else if (GET_CODE (PATTERN (insn
)) == PARALLEL
)
4942 for (j
= 0; j
< XVECLEN (PATTERN (insn
), 0); j
++)
4943 if (GET_CODE (XVECEXP (PATTERN (insn
), 0, j
)) == SET
)
4944 handle_epilogue_set (XVECEXP (PATTERN (insn
), 0, j
), &info
);
4949 info
.sp_equiv_reg
= info
.new_sp_equiv_reg
;
4950 info
.sp_offset
= info
.new_sp_offset
;
4952 /* Now update any constants this insn sets. */
4953 note_stores (PATTERN (insn
), update_epilogue_consts
, &info
);
4957 insns
= get_insns ();
4962 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
4963 structure that contains information about what we've seen so far. We
4964 process this SET by either updating that data or by emitting one or
4968 handle_epilogue_set (rtx set
, struct epi_info
*p
)
4970 /* First handle the case where we are setting SP. Record what it is being
4971 set from, which we must be able to determine */
4972 if (reg_set_p (stack_pointer_rtx
, set
))
4974 gcc_assert (SET_DEST (set
) == stack_pointer_rtx
);
4976 if (GET_CODE (SET_SRC (set
)) == PLUS
)
4978 p
->new_sp_equiv_reg
= XEXP (SET_SRC (set
), 0);
4979 if (GET_CODE (XEXP (SET_SRC (set
), 1)) == CONST_INT
)
4980 p
->new_sp_offset
= INTVAL (XEXP (SET_SRC (set
), 1));
4983 gcc_assert (REG_P (XEXP (SET_SRC (set
), 1))
4984 && (REGNO (XEXP (SET_SRC (set
), 1))
4985 < FIRST_PSEUDO_REGISTER
)
4986 && p
->const_equiv
[REGNO (XEXP (SET_SRC (set
), 1))]);
4988 = INTVAL (p
->const_equiv
[REGNO (XEXP (SET_SRC (set
), 1))]);
4992 p
->new_sp_equiv_reg
= SET_SRC (set
), p
->new_sp_offset
= 0;
4994 /* If we are adjusting SP, we adjust from the old data. */
4995 if (p
->new_sp_equiv_reg
== stack_pointer_rtx
)
4997 p
->new_sp_equiv_reg
= p
->sp_equiv_reg
;
4998 p
->new_sp_offset
+= p
->sp_offset
;
5001 gcc_assert (p
->new_sp_equiv_reg
&& REG_P (p
->new_sp_equiv_reg
));
5006 /* Next handle the case where we are setting SP's equivalent
5007 register. We must not already have a value to set it to. We
5008 could update, but there seems little point in handling that case.
5009 Note that we have to allow for the case where we are setting the
5010 register set in the previous part of a PARALLEL inside a single
5011 insn. But use the old offset for any updates within this insn.
5012 We must allow for the case where the register is being set in a
5013 different (usually wider) mode than Pmode). */
5014 else if (p
->new_sp_equiv_reg
!= 0 && reg_set_p (p
->new_sp_equiv_reg
, set
))
5016 gcc_assert (!p
->equiv_reg_src
5017 && REG_P (p
->new_sp_equiv_reg
)
5018 && REG_P (SET_DEST (set
))
5019 && (GET_MODE_BITSIZE (GET_MODE (SET_DEST (set
)))
5021 && REGNO (p
->new_sp_equiv_reg
) == REGNO (SET_DEST (set
)));
5023 = simplify_replace_rtx (SET_SRC (set
), stack_pointer_rtx
,
5024 plus_constant (p
->sp_equiv_reg
,
5028 /* Otherwise, replace any references to SP in the insn to its new value
5029 and emit the insn. */
5032 SET_SRC (set
) = simplify_replace_rtx (SET_SRC (set
), stack_pointer_rtx
,
5033 plus_constant (p
->sp_equiv_reg
,
5035 SET_DEST (set
) = simplify_replace_rtx (SET_DEST (set
), stack_pointer_rtx
,
5036 plus_constant (p
->sp_equiv_reg
,
5042 /* Update the tracking information for registers set to constants. */
5045 update_epilogue_consts (rtx dest
, const_rtx x
, void *data
)
5047 struct epi_info
*p
= (struct epi_info
*) data
;
5050 if (!REG_P (dest
) || REGNO (dest
) >= FIRST_PSEUDO_REGISTER
)
5053 /* If we are either clobbering a register or doing a partial set,
5054 show we don't know the value. */
5055 else if (GET_CODE (x
) == CLOBBER
|| ! rtx_equal_p (dest
, SET_DEST (x
)))
5056 p
->const_equiv
[REGNO (dest
)] = 0;
5058 /* If we are setting it to a constant, record that constant. */
5059 else if (GET_CODE (SET_SRC (x
)) == CONST_INT
)
5060 p
->const_equiv
[REGNO (dest
)] = SET_SRC (x
);
5062 /* If this is a binary operation between a register we have been tracking
5063 and a constant, see if we can compute a new constant value. */
5064 else if (ARITHMETIC_P (SET_SRC (x
))
5065 && REG_P (XEXP (SET_SRC (x
), 0))
5066 && REGNO (XEXP (SET_SRC (x
), 0)) < FIRST_PSEUDO_REGISTER
5067 && p
->const_equiv
[REGNO (XEXP (SET_SRC (x
), 0))] != 0
5068 && GET_CODE (XEXP (SET_SRC (x
), 1)) == CONST_INT
5069 && 0 != (new = simplify_binary_operation
5070 (GET_CODE (SET_SRC (x
)), GET_MODE (dest
),
5071 p
->const_equiv
[REGNO (XEXP (SET_SRC (x
), 0))],
5072 XEXP (SET_SRC (x
), 1)))
5073 && GET_CODE (new) == CONST_INT
)
5074 p
->const_equiv
[REGNO (dest
)] = new;
5076 /* Otherwise, we can't do anything with this value. */
5078 p
->const_equiv
[REGNO (dest
)] = 0;
5081 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
5084 emit_equiv_load (struct epi_info
*p
)
5086 if (p
->equiv_reg_src
!= 0)
5088 rtx dest
= p
->sp_equiv_reg
;
5090 if (GET_MODE (p
->equiv_reg_src
) != GET_MODE (dest
))
5091 dest
= gen_rtx_REG (GET_MODE (p
->equiv_reg_src
),
5092 REGNO (p
->sp_equiv_reg
));
5094 emit_move_insn (dest
, p
->equiv_reg_src
);
5095 p
->equiv_reg_src
= 0;
5100 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
5101 this into place with notes indicating where the prologue ends and where
5102 the epilogue begins. Update the basic block information when possible. */
5105 thread_prologue_and_epilogue_insns (void)
5109 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
5112 #if defined (HAVE_epilogue) || defined(HAVE_return)
5113 rtx epilogue_end
= NULL_RTX
;
5117 #ifdef HAVE_prologue
5121 seq
= gen_prologue ();
5124 /* Insert an explicit USE for the frame pointer
5125 if the profiling is on and the frame pointer is required. */
5126 if (current_function_profile
&& frame_pointer_needed
)
5127 emit_insn (gen_rtx_USE (VOIDmode
, hard_frame_pointer_rtx
));
5129 /* Retain a map of the prologue insns. */
5130 record_insns (seq
, &prologue
);
5131 emit_note (NOTE_INSN_PROLOGUE_END
);
5133 #ifndef PROFILE_BEFORE_PROLOGUE
5134 /* Ensure that instructions are not moved into the prologue when
5135 profiling is on. The call to the profiling routine can be
5136 emitted within the live range of a call-clobbered register. */
5137 if (current_function_profile
)
5138 emit_insn (gen_blockage ());
5143 set_insn_locators (seq
, prologue_locator
);
5145 /* Can't deal with multiple successors of the entry block
5146 at the moment. Function should always have at least one
5148 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR
));
5150 insert_insn_on_edge (seq
, single_succ_edge (ENTRY_BLOCK_PTR
));
5155 /* If the exit block has no non-fake predecessors, we don't need
5157 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5158 if ((e
->flags
& EDGE_FAKE
) == 0)
5164 if (optimize
&& HAVE_return
)
5166 /* If we're allowed to generate a simple return instruction,
5167 then by definition we don't need a full epilogue. Examine
5168 the block that falls through to EXIT. If it does not
5169 contain any code, examine its predecessors and try to
5170 emit (conditional) return instructions. */
5175 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5176 if (e
->flags
& EDGE_FALLTHRU
)
5182 /* Verify that there are no active instructions in the last block. */
5183 label
= BB_END (last
);
5184 while (label
&& !LABEL_P (label
))
5186 if (active_insn_p (label
))
5188 label
= PREV_INSN (label
);
5191 if (BB_HEAD (last
) == label
&& LABEL_P (label
))
5195 for (ei2
= ei_start (last
->preds
); (e
= ei_safe_edge (ei2
)); )
5197 basic_block bb
= e
->src
;
5200 if (bb
== ENTRY_BLOCK_PTR
)
5207 if (!JUMP_P (jump
) || JUMP_LABEL (jump
) != label
)
5213 /* If we have an unconditional jump, we can replace that
5214 with a simple return instruction. */
5215 if (simplejump_p (jump
))
5217 emit_return_into_block (bb
);
5221 /* If we have a conditional jump, we can try to replace
5222 that with a conditional return instruction. */
5223 else if (condjump_p (jump
))
5225 if (! redirect_jump (jump
, 0, 0))
5231 /* If this block has only one successor, it both jumps
5232 and falls through to the fallthru block, so we can't
5234 if (single_succ_p (bb
))
5246 /* Fix up the CFG for the successful change we just made. */
5247 redirect_edge_succ (e
, EXIT_BLOCK_PTR
);
5250 /* Emit a return insn for the exit fallthru block. Whether
5251 this is still reachable will be determined later. */
5253 emit_barrier_after (BB_END (last
));
5254 emit_return_into_block (last
);
5255 epilogue_end
= BB_END (last
);
5256 single_succ_edge (last
)->flags
&= ~EDGE_FALLTHRU
;
5261 /* Find the edge that falls through to EXIT. Other edges may exist
5262 due to RETURN instructions, but those don't need epilogues.
5263 There really shouldn't be a mixture -- either all should have
5264 been converted or none, however... */
5266 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5267 if (e
->flags
& EDGE_FALLTHRU
)
5272 #ifdef HAVE_epilogue
5276 epilogue_end
= emit_note (NOTE_INSN_EPILOGUE_BEG
);
5278 seq
= gen_epilogue ();
5280 #ifdef INCOMING_RETURN_ADDR_RTX
5281 /* If this function returns with the stack depressed and we can support
5282 it, massage the epilogue to actually do that. */
5283 if (TREE_CODE (TREE_TYPE (current_function_decl
)) == FUNCTION_TYPE
5284 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl
)))
5285 seq
= keep_stack_depressed (seq
);
5288 emit_jump_insn (seq
);
5290 /* Retain a map of the epilogue insns. */
5291 record_insns (seq
, &epilogue
);
5292 set_insn_locators (seq
, epilogue_locator
);
5297 insert_insn_on_edge (seq
, e
);
5305 if (! next_active_insn (BB_END (e
->src
)))
5307 /* We have a fall-through edge to the exit block, the source is not
5308 at the end of the function, and there will be an assembler epilogue
5309 at the end of the function.
5310 We can't use force_nonfallthru here, because that would try to
5311 use return. Inserting a jump 'by hand' is extremely messy, so
5312 we take advantage of cfg_layout_finalize using
5313 fixup_fallthru_exit_predecessor. */
5314 cfg_layout_initialize (0);
5315 FOR_EACH_BB (cur_bb
)
5316 if (cur_bb
->index
>= NUM_FIXED_BLOCKS
5317 && cur_bb
->next_bb
->index
>= NUM_FIXED_BLOCKS
)
5318 cur_bb
->aux
= cur_bb
->next_bb
;
5319 cfg_layout_finalize ();
5325 commit_edge_insertions ();
5327 /* The epilogue insns we inserted may cause the exit edge to no longer
5329 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5331 if (((e
->flags
& EDGE_FALLTHRU
) != 0)
5332 && returnjump_p (BB_END (e
->src
)))
5333 e
->flags
&= ~EDGE_FALLTHRU
;
5337 #ifdef HAVE_sibcall_epilogue
5338 /* Emit sibling epilogues before any sibling call sites. */
5339 for (ei
= ei_start (EXIT_BLOCK_PTR
->preds
); (e
= ei_safe_edge (ei
)); )
5341 basic_block bb
= e
->src
;
5342 rtx insn
= BB_END (bb
);
5345 || ! SIBLING_CALL_P (insn
))
5352 emit_insn (gen_sibcall_epilogue ());
5356 /* Retain a map of the epilogue insns. Used in life analysis to
5357 avoid getting rid of sibcall epilogue insns. Do this before we
5358 actually emit the sequence. */
5359 record_insns (seq
, &sibcall_epilogue
);
5360 set_insn_locators (seq
, epilogue_locator
);
5362 emit_insn_before (seq
, insn
);
5367 #ifdef HAVE_epilogue
5372 /* Similarly, move any line notes that appear after the epilogue.
5373 There is no need, however, to be quite so anal about the existence
5374 of such a note. Also possibly move
5375 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
5377 for (insn
= epilogue_end
; insn
; insn
= next
)
5379 next
= NEXT_INSN (insn
);
5381 && (NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
))
5382 reorder_insns (insn
, insn
, PREV_INSN (epilogue_end
));
5387 /* Threading the prologue and epilogue changes the artificial refs
5388 in the entry and exit blocks. */
5389 epilogue_completed
= 1;
5390 df_update_entry_exit_and_calls ();
5393 /* Reposition the prologue-end and epilogue-begin notes after instruction
5394 scheduling and delayed branch scheduling. */
5397 reposition_prologue_and_epilogue_notes (void)
5399 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
5400 rtx insn
, last
, note
;
5403 if ((len
= VEC_length (int, prologue
)) > 0)
5407 /* Scan from the beginning until we reach the last prologue insn.
5408 We apparently can't depend on basic_block_{head,end} after
5410 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
5414 if (NOTE_KIND (insn
) == NOTE_INSN_PROLOGUE_END
)
5417 else if (contains (insn
, &prologue
))
5427 /* Find the prologue-end note if we haven't already, and
5428 move it to just after the last prologue insn. */
5431 for (note
= last
; (note
= NEXT_INSN (note
));)
5433 && NOTE_KIND (note
) == NOTE_INSN_PROLOGUE_END
)
5437 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
5439 last
= NEXT_INSN (last
);
5440 reorder_insns (note
, note
, last
);
5444 if ((len
= VEC_length (int, epilogue
)) > 0)
5448 /* Scan from the end until we reach the first epilogue insn.
5449 We apparently can't depend on basic_block_{head,end} after
5451 for (insn
= get_last_insn (); insn
; insn
= PREV_INSN (insn
))
5455 if (NOTE_KIND (insn
) == NOTE_INSN_EPILOGUE_BEG
)
5458 else if (contains (insn
, &epilogue
))
5468 /* Find the epilogue-begin note if we haven't already, and
5469 move it to just before the first epilogue insn. */
5472 for (note
= insn
; (note
= PREV_INSN (note
));)
5474 && NOTE_KIND (note
) == NOTE_INSN_EPILOGUE_BEG
)
5478 if (PREV_INSN (last
) != note
)
5479 reorder_insns (note
, note
, PREV_INSN (last
));
5482 #endif /* HAVE_prologue or HAVE_epilogue */
5485 /* Returns the name of the current function. */
5487 current_function_name (void)
5489 return lang_hooks
.decl_printable_name (cfun
->decl
, 2);
5492 /* Returns the raw (mangled) name of the current function. */
5494 current_function_assembler_name (void)
5496 return IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (cfun
->decl
));
5501 rest_of_handle_check_leaf_regs (void)
5503 #ifdef LEAF_REGISTERS
5504 current_function_uses_only_leaf_regs
5505 = optimize
> 0 && only_leaf_regs_used () && leaf_function_p ();
5510 /* Insert a TYPE into the used types hash table of CFUN. */
5512 used_types_insert_helper (tree type
, struct function
*func
)
5514 if (type
!= NULL
&& func
!= NULL
)
5518 if (func
->used_types_hash
== NULL
)
5519 func
->used_types_hash
= htab_create_ggc (37, htab_hash_pointer
,
5520 htab_eq_pointer
, NULL
);
5521 slot
= htab_find_slot (func
->used_types_hash
, type
, INSERT
);
5527 /* Given a type, insert it into the used hash table in cfun. */
5529 used_types_insert (tree t
)
5531 while (POINTER_TYPE_P (t
) || TREE_CODE (t
) == ARRAY_TYPE
)
5533 t
= TYPE_MAIN_VARIANT (t
);
5534 if (debug_info_level
> DINFO_LEVEL_NONE
)
5535 used_types_insert_helper (t
, cfun
);
5538 struct rtl_opt_pass pass_leaf_regs
=
5544 rest_of_handle_check_leaf_regs
, /* execute */
5547 0, /* static_pass_number */
5549 0, /* properties_required */
5550 0, /* properties_provided */
5551 0, /* properties_destroyed */
5552 0, /* todo_flags_start */
5553 0 /* todo_flags_finish */
5558 rest_of_handle_thread_prologue_and_epilogue (void)
5561 cleanup_cfg (CLEANUP_EXPENSIVE
);
5562 /* On some machines, the prologue and epilogue code, or parts thereof,
5563 can be represented as RTL. Doing so lets us schedule insns between
5564 it and the rest of the code and also allows delayed branch
5565 scheduling to operate in the epilogue. */
5567 thread_prologue_and_epilogue_insns ();
5571 struct rtl_opt_pass pass_thread_prologue_and_epilogue
=
5575 "pro_and_epilogue", /* name */
5577 rest_of_handle_thread_prologue_and_epilogue
, /* execute */
5580 0, /* static_pass_number */
5581 TV_THREAD_PROLOGUE_AND_EPILOGUE
, /* tv_id */
5582 0, /* properties_required */
5583 0, /* properties_provided */
5584 0, /* properties_destroyed */
5585 TODO_verify_flow
, /* todo_flags_start */
5588 TODO_df_finish
| TODO_verify_rtl_sharing
|
5589 TODO_ggc_collect
/* todo_flags_finish */
5594 /* This mini-pass fixes fall-out from SSA in asm statements that have
5595 in-out constraints. Say you start with
5598 asm ("": "+mr" (inout));
5601 which is transformed very early to use explicit output and match operands:
5604 asm ("": "=mr" (inout) : "0" (inout));
5607 Or, after SSA and copyprop,
5609 asm ("": "=mr" (inout_2) : "0" (inout_1));
5612 Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
5613 they represent two separate values, so they will get different pseudo
5614 registers during expansion. Then, since the two operands need to match
5615 per the constraints, but use different pseudo registers, reload can
5616 only register a reload for these operands. But reloads can only be
5617 satisfied by hardregs, not by memory, so we need a register for this
5618 reload, just because we are presented with non-matching operands.
5619 So, even though we allow memory for this operand, no memory can be
5620 used for it, just because the two operands don't match. This can
5621 cause reload failures on register-starved targets.
5623 So it's a symptom of reload not being able to use memory for reloads
5624 or, alternatively it's also a symptom of both operands not coming into
5625 reload as matching (in which case the pseudo could go to memory just
5626 fine, as the alternative allows it, and no reload would be necessary).
5627 We fix the latter problem here, by transforming
5629 asm ("": "=mr" (inout_2) : "0" (inout_1));
5634 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
5637 match_asm_constraints_1 (rtx insn
, rtx
*p_sets
, int noutputs
)
5640 bool changed
= false;
5641 rtx op
= SET_SRC (p_sets
[0]);
5642 int ninputs
= ASM_OPERANDS_INPUT_LENGTH (op
);
5643 rtvec inputs
= ASM_OPERANDS_INPUT_VEC (op
);
5644 bool *output_matched
= alloca (noutputs
* sizeof (bool));
5646 memset (output_matched
, 0, noutputs
* sizeof (bool));
5647 for (i
= 0; i
< ninputs
; i
++)
5649 rtx input
, output
, insns
;
5650 const char *constraint
= ASM_OPERANDS_INPUT_CONSTRAINT (op
, i
);
5654 match
= strtoul (constraint
, &end
, 10);
5655 if (end
== constraint
)
5658 gcc_assert (match
< noutputs
);
5659 output
= SET_DEST (p_sets
[match
]);
5660 input
= RTVEC_ELT (inputs
, i
);
5661 /* Only do the transformation for pseudos. */
5662 if (! REG_P (output
)
5663 || rtx_equal_p (output
, input
)
5664 || (GET_MODE (input
) != VOIDmode
5665 && GET_MODE (input
) != GET_MODE (output
)))
5668 /* We can't do anything if the output is also used as input,
5669 as we're going to overwrite it. */
5670 for (j
= 0; j
< ninputs
; j
++)
5671 if (reg_overlap_mentioned_p (output
, RTVEC_ELT (inputs
, j
)))
5676 /* Avoid changing the same input several times. For
5677 asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
5678 only change in once (to out1), rather than changing it
5679 first to out1 and afterwards to out2. */
5682 for (j
= 0; j
< noutputs
; j
++)
5683 if (output_matched
[j
] && input
== SET_DEST (p_sets
[j
]))
5688 output_matched
[match
] = true;
5691 emit_move_insn (output
, input
);
5692 insns
= get_insns ();
5694 emit_insn_before (insns
, insn
);
5696 /* Now replace all mentions of the input with output. We can't
5697 just replace the occurence in inputs[i], as the register might
5698 also be used in some other input (or even in an address of an
5699 output), which would mean possibly increasing the number of
5700 inputs by one (namely 'output' in addition), which might pose
5701 a too complicated problem for reload to solve. E.g. this situation:
5703 asm ("" : "=r" (output), "=m" (input) : "0" (input))
5705 Here 'input' is used in two occurrences as input (once for the
5706 input operand, once for the address in the second output operand).
5707 If we would replace only the occurence of the input operand (to
5708 make the matching) we would be left with this:
5711 asm ("" : "=r" (output), "=m" (input) : "0" (output))
5713 Now we suddenly have two different input values (containing the same
5714 value, but different pseudos) where we formerly had only one.
5715 With more complicated asms this might lead to reload failures
5716 which wouldn't have happen without this pass. So, iterate over
5717 all operands and replace all occurrences of the register used. */
5718 for (j
= 0; j
< noutputs
; j
++)
5719 if (!rtx_equal_p (SET_DEST (p_sets
[j
]), input
)
5720 && reg_overlap_mentioned_p (input
, SET_DEST (p_sets
[j
])))
5721 SET_DEST (p_sets
[j
]) = replace_rtx (SET_DEST (p_sets
[j
]),
5723 for (j
= 0; j
< ninputs
; j
++)
5724 if (reg_overlap_mentioned_p (input
, RTVEC_ELT (inputs
, j
)))
5725 RTVEC_ELT (inputs
, j
) = replace_rtx (RTVEC_ELT (inputs
, j
),
5732 df_insn_rescan (insn
);
5736 rest_of_match_asm_constraints (void)
5739 rtx insn
, pat
, *p_sets
;
5742 if (!cfun
->has_asm_statement
)
5745 df_set_flags (DF_DEFER_INSN_RESCAN
);
5748 FOR_BB_INSNS (bb
, insn
)
5753 pat
= PATTERN (insn
);
5754 if (GET_CODE (pat
) == PARALLEL
)
5755 p_sets
= &XVECEXP (pat
, 0, 0), noutputs
= XVECLEN (pat
, 0);
5756 else if (GET_CODE (pat
) == SET
)
5757 p_sets
= &PATTERN (insn
), noutputs
= 1;
5761 if (GET_CODE (*p_sets
) == SET
5762 && GET_CODE (SET_SRC (*p_sets
)) == ASM_OPERANDS
)
5763 match_asm_constraints_1 (insn
, p_sets
, noutputs
);
5767 return TODO_df_finish
;
5770 struct rtl_opt_pass pass_match_asm_constraints
=
5774 "asmcons", /* name */
5776 rest_of_match_asm_constraints
, /* execute */
5779 0, /* static_pass_number */
5781 0, /* properties_required */
5782 0, /* properties_provided */
5783 0, /* properties_destroyed */
5784 0, /* todo_flags_start */
5785 TODO_dump_func
/* todo_flags_finish */
5790 #include "gt-function.h"