1 /* Expands front end tree to back end RTL for GCC.
2 Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
4 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
22 /* This file handles the generation of rtl code from tree structure
23 at the level of the function as a whole.
24 It creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 `expand_function_start' is called at the beginning of a function,
28 before the function body is parsed, and `expand_function_end' is
29 called after parsing the body.
31 Call `assign_stack_local' to allocate a stack slot for a local variable.
32 This is usually done during the RTL generation for the function body,
33 but it can also be done in the reload pass when a pseudo-register does
34 not get a hard register. */
38 #include "coretypes.h"
49 #include "hard-reg-set.h"
50 #include "insn-config.h"
53 #include "basic-block.h"
58 #include "integrate.h"
59 #include "langhooks.h"
61 #include "cfglayout.h"
63 #include "tree-pass.h"
69 /* So we can assign to cfun in this file. */
72 #ifndef STACK_ALIGNMENT_NEEDED
73 #define STACK_ALIGNMENT_NEEDED 1
76 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
78 /* Some systems use __main in a way incompatible with its use in gcc, in these
79 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
80 give the same symbol without quotes for an alternative entry point. You
81 must define both, or neither. */
83 #define NAME__MAIN "__main"
86 /* Round a value to the lowest integer less than it that is a multiple of
87 the required alignment. Avoid using division in case the value is
88 negative. Assume the alignment is a power of two. */
89 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
91 /* Similar, but round to the next highest integer that meets the
93 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
95 /* Nonzero if function being compiled doesn't contain any calls
96 (ignoring the prologue and epilogue). This is set prior to
97 local register allocation and is valid for the remaining
99 int current_function_is_leaf
;
101 /* Nonzero if function being compiled doesn't modify the stack pointer
102 (ignoring the prologue and epilogue). This is only valid after
103 pass_stack_ptr_mod has run. */
104 int current_function_sp_is_unchanging
;
106 /* Nonzero if the function being compiled is a leaf function which only
107 uses leaf registers. This is valid after reload (specifically after
108 sched2) and is useful only if the port defines LEAF_REGISTERS. */
109 int current_function_uses_only_leaf_regs
;
111 /* Nonzero once virtual register instantiation has been done.
112 assign_stack_local uses frame_pointer_rtx when this is nonzero.
113 calls.c:emit_library_call_value_1 uses it to set up
114 post-instantiation libcalls. */
115 int virtuals_instantiated
;
117 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
118 static GTY(()) int funcdef_no
;
120 /* These variables hold pointers to functions to create and destroy
121 target specific, per-function data structures. */
122 struct machine_function
* (*init_machine_status
) (void);
124 /* The currently compiled function. */
125 struct function
*cfun
= 0;
127 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
128 static VEC(int,heap
) *prologue
;
129 static VEC(int,heap
) *epilogue
;
131 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
133 static VEC(int,heap
) *sibcall_epilogue
;
135 /* In order to evaluate some expressions, such as function calls returning
136 structures in memory, we need to temporarily allocate stack locations.
137 We record each allocated temporary in the following structure.
139 Associated with each temporary slot is a nesting level. When we pop up
140 one level, all temporaries associated with the previous level are freed.
141 Normally, all temporaries are freed after the execution of the statement
142 in which they were created. However, if we are inside a ({...}) grouping,
143 the result may be in a temporary and hence must be preserved. If the
144 result could be in a temporary, we preserve it if we can determine which
145 one it is in. If we cannot determine which temporary may contain the
146 result, all temporaries are preserved. A temporary is preserved by
147 pretending it was allocated at the previous nesting level.
149 Automatic variables are also assigned temporary slots, at the nesting
150 level where they are defined. They are marked a "kept" so that
151 free_temp_slots will not free them. */
153 struct temp_slot
GTY(())
155 /* Points to next temporary slot. */
156 struct temp_slot
*next
;
157 /* Points to previous temporary slot. */
158 struct temp_slot
*prev
;
160 /* The rtx to used to reference the slot. */
162 /* The rtx used to represent the address if not the address of the
163 slot above. May be an EXPR_LIST if multiple addresses exist. */
165 /* The alignment (in bits) of the slot. */
167 /* The size, in units, of the slot. */
169 /* The type of the object in the slot, or zero if it doesn't correspond
170 to a type. We use this to determine whether a slot can be reused.
171 It can be reused if objects of the type of the new slot will always
172 conflict with objects of the type of the old slot. */
174 /* Nonzero if this temporary is currently in use. */
176 /* Nonzero if this temporary has its address taken. */
178 /* Nesting level at which this slot is being used. */
180 /* Nonzero if this should survive a call to free_temp_slots. */
182 /* The offset of the slot from the frame_pointer, including extra space
183 for alignment. This info is for combine_temp_slots. */
184 HOST_WIDE_INT base_offset
;
185 /* The size of the slot, including extra space for alignment. This
186 info is for combine_temp_slots. */
187 HOST_WIDE_INT full_size
;
190 /* Forward declarations. */
192 static struct temp_slot
*find_temp_slot_from_address (rtx
);
193 static void pad_to_arg_alignment (struct args_size
*, int, struct args_size
*);
194 static void pad_below (struct args_size
*, enum machine_mode
, tree
);
195 static void reorder_blocks_1 (rtx
, tree
, VEC(tree
,heap
) **);
196 static int all_blocks (tree
, tree
*);
197 static tree
*get_block_vector (tree
, int *);
198 extern tree
debug_find_var_in_block_tree (tree
, tree
);
199 /* We always define `record_insns' even if it's not used so that we
200 can always export `prologue_epilogue_contains'. */
201 static void record_insns (rtx
, VEC(int,heap
) **) ATTRIBUTE_UNUSED
;
202 static int contains (const_rtx
, VEC(int,heap
) **);
204 static void emit_return_into_block (basic_block
);
206 static void prepare_function_start (void);
207 static void do_clobber_return_reg (rtx
, void *);
208 static void do_use_return_reg (rtx
, void *);
209 static void set_insn_locators (rtx
, int) ATTRIBUTE_UNUSED
;
211 /* Stack of nested functions. */
212 /* Keep track of the cfun stack. */
214 typedef struct function
*function_p
;
216 DEF_VEC_P(function_p
);
217 DEF_VEC_ALLOC_P(function_p
,heap
);
218 static VEC(function_p
,heap
) *function_context_stack
;
220 /* Save the current context for compilation of a nested function.
221 This is called from language-specific code. */
224 push_function_context (void)
227 allocate_struct_function (NULL
, false);
229 VEC_safe_push (function_p
, heap
, function_context_stack
, cfun
);
233 /* Restore the last saved context, at the end of a nested function.
234 This function is called from language-specific code. */
237 pop_function_context (void)
239 struct function
*p
= VEC_pop (function_p
, function_context_stack
);
241 current_function_decl
= p
->decl
;
243 /* Reset variables that have known state during rtx generation. */
244 virtuals_instantiated
= 0;
245 generating_concat_p
= 1;
248 /* Clear out all parts of the state in F that can safely be discarded
249 after the function has been parsed, but not compiled, to let
250 garbage collection reclaim the memory. */
253 free_after_parsing (struct function
*f
)
258 /* Clear out all parts of the state in F that can safely be discarded
259 after the function has been compiled, to let garbage collection
260 reclaim the memory. */
263 free_after_compilation (struct function
*f
)
265 VEC_free (int, heap
, prologue
);
266 VEC_free (int, heap
, epilogue
);
267 VEC_free (int, heap
, sibcall_epilogue
);
268 if (crtl
->emit
.regno_pointer_align
)
269 free (crtl
->emit
.regno_pointer_align
);
271 memset (crtl
, 0, sizeof (struct rtl_data
));
276 regno_reg_rtx
= NULL
;
277 insn_locators_free ();
280 /* Return size needed for stack frame based on slots so far allocated.
281 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
282 the caller may have to do that. */
285 get_frame_size (void)
287 if (FRAME_GROWS_DOWNWARD
)
288 return -frame_offset
;
293 /* Issue an error message and return TRUE if frame OFFSET overflows in
294 the signed target pointer arithmetics for function FUNC. Otherwise
298 frame_offset_overflow (HOST_WIDE_INT offset
, tree func
)
300 unsigned HOST_WIDE_INT size
= FRAME_GROWS_DOWNWARD
? -offset
: offset
;
302 if (size
> ((unsigned HOST_WIDE_INT
) 1 << (GET_MODE_BITSIZE (Pmode
) - 1))
303 /* Leave room for the fixed part of the frame. */
304 - 64 * UNITS_PER_WORD
)
306 error ("%Jtotal size of local objects too large", func
);
313 /* Return stack slot alignment in bits for TYPE and MODE. */
316 get_stack_local_alignment (tree type
, enum machine_mode mode
)
318 unsigned int alignment
;
321 alignment
= BIGGEST_ALIGNMENT
;
323 alignment
= GET_MODE_ALIGNMENT (mode
);
325 /* Allow the frond-end to (possibly) increase the alignment of this
328 type
= lang_hooks
.types
.type_for_mode (mode
, 0);
330 return STACK_SLOT_ALIGNMENT (type
, mode
, alignment
);
333 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
334 with machine mode MODE.
336 ALIGN controls the amount of alignment for the address of the slot:
337 0 means according to MODE,
338 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
339 -2 means use BITS_PER_UNIT,
340 positive specifies alignment boundary in bits.
342 If REDUCE_ALIGNMENT_OK is true, it is OK to reduce alignment.
344 We do not round to stack_boundary here. */
347 assign_stack_local_1 (enum machine_mode mode
, HOST_WIDE_INT size
,
349 bool reduce_alignment_ok ATTRIBUTE_UNUSED
)
352 int bigend_correction
= 0;
353 unsigned int alignment
, alignment_in_bits
;
354 int frame_off
, frame_alignment
, frame_phase
;
358 alignment
= get_stack_local_alignment (NULL
, mode
);
359 alignment
/= BITS_PER_UNIT
;
361 else if (align
== -1)
363 alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
364 size
= CEIL_ROUND (size
, alignment
);
366 else if (align
== -2)
367 alignment
= 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
369 alignment
= align
/ BITS_PER_UNIT
;
371 alignment_in_bits
= alignment
* BITS_PER_UNIT
;
373 if (FRAME_GROWS_DOWNWARD
)
374 frame_offset
-= size
;
376 /* Ignore alignment if it exceeds MAX_SUPPORTED_STACK_ALIGNMENT. */
377 if (alignment_in_bits
> MAX_SUPPORTED_STACK_ALIGNMENT
)
379 alignment_in_bits
= MAX_SUPPORTED_STACK_ALIGNMENT
;
380 alignment
= alignment_in_bits
/ BITS_PER_UNIT
;
383 if (SUPPORTS_STACK_ALIGNMENT
)
385 if (crtl
->stack_alignment_estimated
< alignment_in_bits
)
387 if (!crtl
->stack_realign_processed
)
388 crtl
->stack_alignment_estimated
= alignment_in_bits
;
391 /* If stack is realigned and stack alignment value
392 hasn't been finalized, it is OK not to increase
393 stack_alignment_estimated. The bigger alignment
394 requirement is recorded in stack_alignment_needed
396 gcc_assert (!crtl
->stack_realign_finalized
);
397 if (!crtl
->stack_realign_needed
)
399 /* It is OK to reduce the alignment as long as the
400 requested size is 0 or the estimated stack
401 alignment >= mode alignment. */
402 gcc_assert (reduce_alignment_ok
404 || (crtl
->stack_alignment_estimated
405 >= GET_MODE_ALIGNMENT (mode
)));
406 alignment_in_bits
= crtl
->stack_alignment_estimated
;
407 alignment
= alignment_in_bits
/ BITS_PER_UNIT
;
413 if (crtl
->stack_alignment_needed
< alignment_in_bits
)
414 crtl
->stack_alignment_needed
= alignment_in_bits
;
415 if (crtl
->max_used_stack_slot_alignment
< crtl
->stack_alignment_needed
)
416 crtl
->max_used_stack_slot_alignment
= crtl
->stack_alignment_needed
;
418 /* Calculate how many bytes the start of local variables is off from
420 frame_alignment
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
421 frame_off
= STARTING_FRAME_OFFSET
% frame_alignment
;
422 frame_phase
= frame_off
? frame_alignment
- frame_off
: 0;
424 /* Round the frame offset to the specified alignment. The default is
425 to always honor requests to align the stack but a port may choose to
426 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
427 if (STACK_ALIGNMENT_NEEDED
431 /* We must be careful here, since FRAME_OFFSET might be negative and
432 division with a negative dividend isn't as well defined as we might
433 like. So we instead assume that ALIGNMENT is a power of two and
434 use logical operations which are unambiguous. */
435 if (FRAME_GROWS_DOWNWARD
)
437 = (FLOOR_ROUND (frame_offset
- frame_phase
,
438 (unsigned HOST_WIDE_INT
) alignment
)
442 = (CEIL_ROUND (frame_offset
- frame_phase
,
443 (unsigned HOST_WIDE_INT
) alignment
)
447 /* On a big-endian machine, if we are allocating more space than we will use,
448 use the least significant bytes of those that are allocated. */
449 if (BYTES_BIG_ENDIAN
&& mode
!= BLKmode
&& GET_MODE_SIZE (mode
) < size
)
450 bigend_correction
= size
- GET_MODE_SIZE (mode
);
452 /* If we have already instantiated virtual registers, return the actual
453 address relative to the frame pointer. */
454 if (virtuals_instantiated
)
455 addr
= plus_constant (frame_pointer_rtx
,
457 (frame_offset
+ bigend_correction
458 + STARTING_FRAME_OFFSET
, Pmode
));
460 addr
= plus_constant (virtual_stack_vars_rtx
,
462 (frame_offset
+ bigend_correction
,
465 if (!FRAME_GROWS_DOWNWARD
)
466 frame_offset
+= size
;
468 x
= gen_rtx_MEM (mode
, addr
);
469 set_mem_align (x
, alignment_in_bits
);
470 MEM_NOTRAP_P (x
) = 1;
473 = gen_rtx_EXPR_LIST (VOIDmode
, x
, stack_slot_list
);
475 if (frame_offset_overflow (frame_offset
, current_function_decl
))
481 /* Wrap up assign_stack_local_1 with last parameter as false. */
484 assign_stack_local (enum machine_mode mode
, HOST_WIDE_INT size
, int align
)
486 return assign_stack_local_1 (mode
, size
, align
, false);
489 /* Removes temporary slot TEMP from LIST. */
492 cut_slot_from_list (struct temp_slot
*temp
, struct temp_slot
**list
)
495 temp
->next
->prev
= temp
->prev
;
497 temp
->prev
->next
= temp
->next
;
501 temp
->prev
= temp
->next
= NULL
;
504 /* Inserts temporary slot TEMP to LIST. */
507 insert_slot_to_list (struct temp_slot
*temp
, struct temp_slot
**list
)
511 (*list
)->prev
= temp
;
516 /* Returns the list of used temp slots at LEVEL. */
518 static struct temp_slot
**
519 temp_slots_at_level (int level
)
521 if (level
>= (int) VEC_length (temp_slot_p
, used_temp_slots
))
522 VEC_safe_grow_cleared (temp_slot_p
, gc
, used_temp_slots
, level
+ 1);
524 return &(VEC_address (temp_slot_p
, used_temp_slots
)[level
]);
527 /* Returns the maximal temporary slot level. */
530 max_slot_level (void)
532 if (!used_temp_slots
)
535 return VEC_length (temp_slot_p
, used_temp_slots
) - 1;
538 /* Moves temporary slot TEMP to LEVEL. */
541 move_slot_to_level (struct temp_slot
*temp
, int level
)
543 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
544 insert_slot_to_list (temp
, temp_slots_at_level (level
));
548 /* Make temporary slot TEMP available. */
551 make_slot_available (struct temp_slot
*temp
)
553 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
554 insert_slot_to_list (temp
, &avail_temp_slots
);
559 /* Allocate a temporary stack slot and record it for possible later
562 MODE is the machine mode to be given to the returned rtx.
564 SIZE is the size in units of the space required. We do no rounding here
565 since assign_stack_local will do any required rounding.
567 KEEP is 1 if this slot is to be retained after a call to
568 free_temp_slots. Automatic variables for a block are allocated
569 with this flag. KEEP values of 2 or 3 were needed respectively
570 for variables whose lifetime is controlled by CLEANUP_POINT_EXPRs
571 or for SAVE_EXPRs, but they are now unused.
573 TYPE is the type that will be used for the stack slot. */
576 assign_stack_temp_for_type (enum machine_mode mode
, HOST_WIDE_INT size
,
580 struct temp_slot
*p
, *best_p
= 0, *selected
= NULL
, **pp
;
583 /* If SIZE is -1 it means that somebody tried to allocate a temporary
584 of a variable size. */
585 gcc_assert (size
!= -1);
587 /* These are now unused. */
588 gcc_assert (keep
<= 1);
590 align
= get_stack_local_alignment (type
, mode
);
592 /* Try to find an available, already-allocated temporary of the proper
593 mode which meets the size and alignment requirements. Choose the
594 smallest one with the closest alignment.
596 If assign_stack_temp is called outside of the tree->rtl expansion,
597 we cannot reuse the stack slots (that may still refer to
598 VIRTUAL_STACK_VARS_REGNUM). */
599 if (!virtuals_instantiated
)
601 for (p
= avail_temp_slots
; p
; p
= p
->next
)
603 if (p
->align
>= align
&& p
->size
>= size
604 && GET_MODE (p
->slot
) == mode
605 && objects_must_conflict_p (p
->type
, type
)
606 && (best_p
== 0 || best_p
->size
> p
->size
607 || (best_p
->size
== p
->size
&& best_p
->align
> p
->align
)))
609 if (p
->align
== align
&& p
->size
== size
)
612 cut_slot_from_list (selected
, &avail_temp_slots
);
621 /* Make our best, if any, the one to use. */
625 cut_slot_from_list (selected
, &avail_temp_slots
);
627 /* If there are enough aligned bytes left over, make them into a new
628 temp_slot so that the extra bytes don't get wasted. Do this only
629 for BLKmode slots, so that we can be sure of the alignment. */
630 if (GET_MODE (best_p
->slot
) == BLKmode
)
632 int alignment
= best_p
->align
/ BITS_PER_UNIT
;
633 HOST_WIDE_INT rounded_size
= CEIL_ROUND (size
, alignment
);
635 if (best_p
->size
- rounded_size
>= alignment
)
637 p
= GGC_NEW (struct temp_slot
);
638 p
->in_use
= p
->addr_taken
= 0;
639 p
->size
= best_p
->size
- rounded_size
;
640 p
->base_offset
= best_p
->base_offset
+ rounded_size
;
641 p
->full_size
= best_p
->full_size
- rounded_size
;
642 p
->slot
= adjust_address_nv (best_p
->slot
, BLKmode
, rounded_size
);
643 p
->align
= best_p
->align
;
645 p
->type
= best_p
->type
;
646 insert_slot_to_list (p
, &avail_temp_slots
);
648 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, p
->slot
,
651 best_p
->size
= rounded_size
;
652 best_p
->full_size
= rounded_size
;
657 /* If we still didn't find one, make a new temporary. */
660 HOST_WIDE_INT frame_offset_old
= frame_offset
;
662 p
= GGC_NEW (struct temp_slot
);
664 /* We are passing an explicit alignment request to assign_stack_local.
665 One side effect of that is assign_stack_local will not round SIZE
666 to ensure the frame offset remains suitably aligned.
668 So for requests which depended on the rounding of SIZE, we go ahead
669 and round it now. We also make sure ALIGNMENT is at least
670 BIGGEST_ALIGNMENT. */
671 gcc_assert (mode
!= BLKmode
|| align
== BIGGEST_ALIGNMENT
);
672 p
->slot
= assign_stack_local (mode
,
674 ? CEIL_ROUND (size
, (int) align
/ BITS_PER_UNIT
)
680 /* The following slot size computation is necessary because we don't
681 know the actual size of the temporary slot until assign_stack_local
682 has performed all the frame alignment and size rounding for the
683 requested temporary. Note that extra space added for alignment
684 can be either above or below this stack slot depending on which
685 way the frame grows. We include the extra space if and only if it
686 is above this slot. */
687 if (FRAME_GROWS_DOWNWARD
)
688 p
->size
= frame_offset_old
- frame_offset
;
692 /* Now define the fields used by combine_temp_slots. */
693 if (FRAME_GROWS_DOWNWARD
)
695 p
->base_offset
= frame_offset
;
696 p
->full_size
= frame_offset_old
- frame_offset
;
700 p
->base_offset
= frame_offset_old
;
701 p
->full_size
= frame_offset
- frame_offset_old
;
712 p
->level
= temp_slot_level
;
715 pp
= temp_slots_at_level (p
->level
);
716 insert_slot_to_list (p
, pp
);
718 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
719 slot
= gen_rtx_MEM (mode
, XEXP (p
->slot
, 0));
720 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, slot
, stack_slot_list
);
722 /* If we know the alias set for the memory that will be used, use
723 it. If there's no TYPE, then we don't know anything about the
724 alias set for the memory. */
725 set_mem_alias_set (slot
, type
? get_alias_set (type
) : 0);
726 set_mem_align (slot
, align
);
728 /* If a type is specified, set the relevant flags. */
731 MEM_VOLATILE_P (slot
) = TYPE_VOLATILE (type
);
732 MEM_SET_IN_STRUCT_P (slot
, (AGGREGATE_TYPE_P (type
)
733 || TREE_CODE (type
) == COMPLEX_TYPE
));
735 MEM_NOTRAP_P (slot
) = 1;
740 /* Allocate a temporary stack slot and record it for possible later
741 reuse. First three arguments are same as in preceding function. */
744 assign_stack_temp (enum machine_mode mode
, HOST_WIDE_INT size
, int keep
)
746 return assign_stack_temp_for_type (mode
, size
, keep
, NULL_TREE
);
749 /* Assign a temporary.
750 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
751 and so that should be used in error messages. In either case, we
752 allocate of the given type.
753 KEEP is as for assign_stack_temp.
754 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
755 it is 0 if a register is OK.
756 DONT_PROMOTE is 1 if we should not promote values in register
760 assign_temp (tree type_or_decl
, int keep
, int memory_required
,
761 int dont_promote ATTRIBUTE_UNUSED
)
764 enum machine_mode mode
;
769 if (DECL_P (type_or_decl
))
770 decl
= type_or_decl
, type
= TREE_TYPE (decl
);
772 decl
= NULL
, type
= type_or_decl
;
774 mode
= TYPE_MODE (type
);
776 unsignedp
= TYPE_UNSIGNED (type
);
779 if (mode
== BLKmode
|| memory_required
)
781 HOST_WIDE_INT size
= int_size_in_bytes (type
);
784 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
785 problems with allocating the stack space. */
789 /* Unfortunately, we don't yet know how to allocate variable-sized
790 temporaries. However, sometimes we can find a fixed upper limit on
791 the size, so try that instead. */
793 size
= max_int_size_in_bytes (type
);
795 /* The size of the temporary may be too large to fit into an integer. */
796 /* ??? Not sure this should happen except for user silliness, so limit
797 this to things that aren't compiler-generated temporaries. The
798 rest of the time we'll die in assign_stack_temp_for_type. */
799 if (decl
&& size
== -1
800 && TREE_CODE (TYPE_SIZE_UNIT (type
)) == INTEGER_CST
)
802 error ("size of variable %q+D is too large", decl
);
806 tmp
= assign_stack_temp_for_type (mode
, size
, keep
, type
);
812 mode
= promote_mode (type
, mode
, &unsignedp
, 0);
815 return gen_reg_rtx (mode
);
818 /* Combine temporary stack slots which are adjacent on the stack.
820 This allows for better use of already allocated stack space. This is only
821 done for BLKmode slots because we can be sure that we won't have alignment
822 problems in this case. */
825 combine_temp_slots (void)
827 struct temp_slot
*p
, *q
, *next
, *next_q
;
830 /* We can't combine slots, because the information about which slot
831 is in which alias set will be lost. */
832 if (flag_strict_aliasing
)
835 /* If there are a lot of temp slots, don't do anything unless
836 high levels of optimization. */
837 if (! flag_expensive_optimizations
)
838 for (p
= avail_temp_slots
, num_slots
= 0; p
; p
= p
->next
, num_slots
++)
839 if (num_slots
> 100 || (num_slots
> 10 && optimize
== 0))
842 for (p
= avail_temp_slots
; p
; p
= next
)
848 if (GET_MODE (p
->slot
) != BLKmode
)
851 for (q
= p
->next
; q
; q
= next_q
)
857 if (GET_MODE (q
->slot
) != BLKmode
)
860 if (p
->base_offset
+ p
->full_size
== q
->base_offset
)
862 /* Q comes after P; combine Q into P. */
864 p
->full_size
+= q
->full_size
;
867 else if (q
->base_offset
+ q
->full_size
== p
->base_offset
)
869 /* P comes after Q; combine P into Q. */
871 q
->full_size
+= p
->full_size
;
876 cut_slot_from_list (q
, &avail_temp_slots
);
879 /* Either delete P or advance past it. */
881 cut_slot_from_list (p
, &avail_temp_slots
);
885 /* Find the temp slot corresponding to the object at address X. */
887 static struct temp_slot
*
888 find_temp_slot_from_address (rtx x
)
894 for (i
= max_slot_level (); i
>= 0; i
--)
895 for (p
= *temp_slots_at_level (i
); p
; p
= p
->next
)
897 if (XEXP (p
->slot
, 0) == x
899 || (GET_CODE (x
) == PLUS
900 && XEXP (x
, 0) == virtual_stack_vars_rtx
901 && GET_CODE (XEXP (x
, 1)) == CONST_INT
902 && INTVAL (XEXP (x
, 1)) >= p
->base_offset
903 && INTVAL (XEXP (x
, 1)) < p
->base_offset
+ p
->full_size
))
906 else if (p
->address
!= 0 && GET_CODE (p
->address
) == EXPR_LIST
)
907 for (next
= p
->address
; next
; next
= XEXP (next
, 1))
908 if (XEXP (next
, 0) == x
)
912 /* If we have a sum involving a register, see if it points to a temp
914 if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 0))
915 && (p
= find_temp_slot_from_address (XEXP (x
, 0))) != 0)
917 else if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 1))
918 && (p
= find_temp_slot_from_address (XEXP (x
, 1))) != 0)
924 /* Indicate that NEW_RTX is an alternate way of referring to the temp
925 slot that previously was known by OLD_RTX. */
928 update_temp_slot_address (rtx old_rtx
, rtx new_rtx
)
932 if (rtx_equal_p (old_rtx
, new_rtx
))
935 p
= find_temp_slot_from_address (old_rtx
);
937 /* If we didn't find one, see if both OLD_RTX is a PLUS. If so, and
938 NEW_RTX is a register, see if one operand of the PLUS is a
939 temporary location. If so, NEW_RTX points into it. Otherwise,
940 if both OLD_RTX and NEW_RTX are a PLUS and if there is a register
941 in common between them. If so, try a recursive call on those
945 if (GET_CODE (old_rtx
) != PLUS
)
950 update_temp_slot_address (XEXP (old_rtx
, 0), new_rtx
);
951 update_temp_slot_address (XEXP (old_rtx
, 1), new_rtx
);
954 else if (GET_CODE (new_rtx
) != PLUS
)
957 if (rtx_equal_p (XEXP (old_rtx
, 0), XEXP (new_rtx
, 0)))
958 update_temp_slot_address (XEXP (old_rtx
, 1), XEXP (new_rtx
, 1));
959 else if (rtx_equal_p (XEXP (old_rtx
, 1), XEXP (new_rtx
, 0)))
960 update_temp_slot_address (XEXP (old_rtx
, 0), XEXP (new_rtx
, 1));
961 else if (rtx_equal_p (XEXP (old_rtx
, 0), XEXP (new_rtx
, 1)))
962 update_temp_slot_address (XEXP (old_rtx
, 1), XEXP (new_rtx
, 0));
963 else if (rtx_equal_p (XEXP (old_rtx
, 1), XEXP (new_rtx
, 1)))
964 update_temp_slot_address (XEXP (old_rtx
, 0), XEXP (new_rtx
, 0));
969 /* Otherwise add an alias for the temp's address. */
970 else if (p
->address
== 0)
971 p
->address
= new_rtx
;
974 if (GET_CODE (p
->address
) != EXPR_LIST
)
975 p
->address
= gen_rtx_EXPR_LIST (VOIDmode
, p
->address
, NULL_RTX
);
977 p
->address
= gen_rtx_EXPR_LIST (VOIDmode
, new_rtx
, p
->address
);
981 /* If X could be a reference to a temporary slot, mark the fact that its
982 address was taken. */
985 mark_temp_addr_taken (rtx x
)
992 /* If X is not in memory or is at a constant address, it cannot be in
994 if (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0)))
997 p
= find_temp_slot_from_address (XEXP (x
, 0));
1002 /* If X could be a reference to a temporary slot, mark that slot as
1003 belonging to the to one level higher than the current level. If X
1004 matched one of our slots, just mark that one. Otherwise, we can't
1005 easily predict which it is, so upgrade all of them. Kept slots
1006 need not be touched.
1008 This is called when an ({...}) construct occurs and a statement
1009 returns a value in memory. */
1012 preserve_temp_slots (rtx x
)
1014 struct temp_slot
*p
= 0, *next
;
1016 /* If there is no result, we still might have some objects whose address
1017 were taken, so we need to make sure they stay around. */
1020 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1025 move_slot_to_level (p
, temp_slot_level
- 1);
1031 /* If X is a register that is being used as a pointer, see if we have
1032 a temporary slot we know it points to. To be consistent with
1033 the code below, we really should preserve all non-kept slots
1034 if we can't find a match, but that seems to be much too costly. */
1035 if (REG_P (x
) && REG_POINTER (x
))
1036 p
= find_temp_slot_from_address (x
);
1038 /* If X is not in memory or is at a constant address, it cannot be in
1039 a temporary slot, but it can contain something whose address was
1041 if (p
== 0 && (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0))))
1043 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1048 move_slot_to_level (p
, temp_slot_level
- 1);
1054 /* First see if we can find a match. */
1056 p
= find_temp_slot_from_address (XEXP (x
, 0));
1060 /* Move everything at our level whose address was taken to our new
1061 level in case we used its address. */
1062 struct temp_slot
*q
;
1064 if (p
->level
== temp_slot_level
)
1066 for (q
= *temp_slots_at_level (temp_slot_level
); q
; q
= next
)
1070 if (p
!= q
&& q
->addr_taken
)
1071 move_slot_to_level (q
, temp_slot_level
- 1);
1074 move_slot_to_level (p
, temp_slot_level
- 1);
1080 /* Otherwise, preserve all non-kept slots at this level. */
1081 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1086 move_slot_to_level (p
, temp_slot_level
- 1);
1090 /* Free all temporaries used so far. This is normally called at the
1091 end of generating code for a statement. */
1094 free_temp_slots (void)
1096 struct temp_slot
*p
, *next
;
1098 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1103 make_slot_available (p
);
1106 combine_temp_slots ();
1109 /* Push deeper into the nesting level for stack temporaries. */
1112 push_temp_slots (void)
1117 /* Pop a temporary nesting level. All slots in use in the current level
1121 pop_temp_slots (void)
1123 struct temp_slot
*p
, *next
;
1125 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1128 make_slot_available (p
);
1131 combine_temp_slots ();
1136 /* Initialize temporary slots. */
1139 init_temp_slots (void)
1141 /* We have not allocated any temporaries yet. */
1142 avail_temp_slots
= 0;
1143 used_temp_slots
= 0;
1144 temp_slot_level
= 0;
1147 /* These routines are responsible for converting virtual register references
1148 to the actual hard register references once RTL generation is complete.
1150 The following four variables are used for communication between the
1151 routines. They contain the offsets of the virtual registers from their
1152 respective hard registers. */
1154 static int in_arg_offset
;
1155 static int var_offset
;
1156 static int dynamic_offset
;
1157 static int out_arg_offset
;
1158 static int cfa_offset
;
1160 /* In most machines, the stack pointer register is equivalent to the bottom
1163 #ifndef STACK_POINTER_OFFSET
1164 #define STACK_POINTER_OFFSET 0
1167 /* If not defined, pick an appropriate default for the offset of dynamically
1168 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1169 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1171 #ifndef STACK_DYNAMIC_OFFSET
1173 /* The bottom of the stack points to the actual arguments. If
1174 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1175 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1176 stack space for register parameters is not pushed by the caller, but
1177 rather part of the fixed stack areas and hence not included in
1178 `crtl->outgoing_args_size'. Nevertheless, we must allow
1179 for it when allocating stack dynamic objects. */
1181 #if defined(REG_PARM_STACK_SPACE)
1182 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1183 ((ACCUMULATE_OUTGOING_ARGS \
1184 ? (crtl->outgoing_args_size \
1185 + (OUTGOING_REG_PARM_STACK_SPACE ((!(FNDECL) ? NULL_TREE : TREE_TYPE (FNDECL))) ? 0 \
1186 : REG_PARM_STACK_SPACE (FNDECL))) \
1187 : 0) + (STACK_POINTER_OFFSET))
1189 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1190 ((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : 0) \
1191 + (STACK_POINTER_OFFSET))
1196 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1197 is a virtual register, return the equivalent hard register and set the
1198 offset indirectly through the pointer. Otherwise, return 0. */
1201 instantiate_new_reg (rtx x
, HOST_WIDE_INT
*poffset
)
1204 HOST_WIDE_INT offset
;
1206 if (x
== virtual_incoming_args_rtx
)
1208 if (stack_realign_drap
)
1210 /* Replace virtual_incoming_args_rtx with internal arg
1211 pointer if DRAP is used to realign stack. */
1212 new_rtx
= crtl
->args
.internal_arg_pointer
;
1216 new_rtx
= arg_pointer_rtx
, offset
= in_arg_offset
;
1218 else if (x
== virtual_stack_vars_rtx
)
1219 new_rtx
= frame_pointer_rtx
, offset
= var_offset
;
1220 else if (x
== virtual_stack_dynamic_rtx
)
1221 new_rtx
= stack_pointer_rtx
, offset
= dynamic_offset
;
1222 else if (x
== virtual_outgoing_args_rtx
)
1223 new_rtx
= stack_pointer_rtx
, offset
= out_arg_offset
;
1224 else if (x
== virtual_cfa_rtx
)
1226 #ifdef FRAME_POINTER_CFA_OFFSET
1227 new_rtx
= frame_pointer_rtx
;
1229 new_rtx
= arg_pointer_rtx
;
1231 offset
= cfa_offset
;
1240 /* A subroutine of instantiate_virtual_regs, called via for_each_rtx.
1241 Instantiate any virtual registers present inside of *LOC. The expression
1242 is simplified, as much as possible, but is not to be considered "valid"
1243 in any sense implied by the target. If any change is made, set CHANGED
1247 instantiate_virtual_regs_in_rtx (rtx
*loc
, void *data
)
1249 HOST_WIDE_INT offset
;
1250 bool *changed
= (bool *) data
;
1257 switch (GET_CODE (x
))
1260 new_rtx
= instantiate_new_reg (x
, &offset
);
1263 *loc
= plus_constant (new_rtx
, offset
);
1270 new_rtx
= instantiate_new_reg (XEXP (x
, 0), &offset
);
1273 new_rtx
= plus_constant (new_rtx
, offset
);
1274 *loc
= simplify_gen_binary (PLUS
, GET_MODE (x
), new_rtx
, XEXP (x
, 1));
1280 /* FIXME -- from old code */
1281 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1282 we can commute the PLUS and SUBREG because pointers into the
1283 frame are well-behaved. */
1293 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1294 matches the predicate for insn CODE operand OPERAND. */
1297 safe_insn_predicate (int code
, int operand
, rtx x
)
1299 const struct insn_operand_data
*op_data
;
1304 op_data
= &insn_data
[code
].operand
[operand
];
1305 if (op_data
->predicate
== NULL
)
1308 return op_data
->predicate (x
, op_data
->mode
);
1311 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1312 registers present inside of insn. The result will be a valid insn. */
1315 instantiate_virtual_regs_in_insn (rtx insn
)
1317 HOST_WIDE_INT offset
;
1319 bool any_change
= false;
1320 rtx set
, new_rtx
, x
, seq
;
1322 /* There are some special cases to be handled first. */
1323 set
= single_set (insn
);
1326 /* We're allowed to assign to a virtual register. This is interpreted
1327 to mean that the underlying register gets assigned the inverse
1328 transformation. This is used, for example, in the handling of
1330 new_rtx
= instantiate_new_reg (SET_DEST (set
), &offset
);
1335 for_each_rtx (&SET_SRC (set
), instantiate_virtual_regs_in_rtx
, NULL
);
1336 x
= simplify_gen_binary (PLUS
, GET_MODE (new_rtx
), SET_SRC (set
),
1338 x
= force_operand (x
, new_rtx
);
1340 emit_move_insn (new_rtx
, x
);
1345 emit_insn_before (seq
, insn
);
1350 /* Handle a straight copy from a virtual register by generating a
1351 new add insn. The difference between this and falling through
1352 to the generic case is avoiding a new pseudo and eliminating a
1353 move insn in the initial rtl stream. */
1354 new_rtx
= instantiate_new_reg (SET_SRC (set
), &offset
);
1355 if (new_rtx
&& offset
!= 0
1356 && REG_P (SET_DEST (set
))
1357 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1361 x
= expand_simple_binop (GET_MODE (SET_DEST (set
)), PLUS
,
1362 new_rtx
, GEN_INT (offset
), SET_DEST (set
),
1363 1, OPTAB_LIB_WIDEN
);
1364 if (x
!= SET_DEST (set
))
1365 emit_move_insn (SET_DEST (set
), x
);
1370 emit_insn_before (seq
, insn
);
1375 extract_insn (insn
);
1376 insn_code
= INSN_CODE (insn
);
1378 /* Handle a plus involving a virtual register by determining if the
1379 operands remain valid if they're modified in place. */
1380 if (GET_CODE (SET_SRC (set
)) == PLUS
1381 && recog_data
.n_operands
>= 3
1382 && recog_data
.operand_loc
[1] == &XEXP (SET_SRC (set
), 0)
1383 && recog_data
.operand_loc
[2] == &XEXP (SET_SRC (set
), 1)
1384 && GET_CODE (recog_data
.operand
[2]) == CONST_INT
1385 && (new_rtx
= instantiate_new_reg (recog_data
.operand
[1], &offset
)))
1387 offset
+= INTVAL (recog_data
.operand
[2]);
1389 /* If the sum is zero, then replace with a plain move. */
1391 && REG_P (SET_DEST (set
))
1392 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1395 emit_move_insn (SET_DEST (set
), new_rtx
);
1399 emit_insn_before (seq
, insn
);
1404 x
= gen_int_mode (offset
, recog_data
.operand_mode
[2]);
1406 /* Using validate_change and apply_change_group here leaves
1407 recog_data in an invalid state. Since we know exactly what
1408 we want to check, do those two by hand. */
1409 if (safe_insn_predicate (insn_code
, 1, new_rtx
)
1410 && safe_insn_predicate (insn_code
, 2, x
))
1412 *recog_data
.operand_loc
[1] = recog_data
.operand
[1] = new_rtx
;
1413 *recog_data
.operand_loc
[2] = recog_data
.operand
[2] = x
;
1416 /* Fall through into the regular operand fixup loop in
1417 order to take care of operands other than 1 and 2. */
1423 extract_insn (insn
);
1424 insn_code
= INSN_CODE (insn
);
1427 /* In the general case, we expect virtual registers to appear only in
1428 operands, and then only as either bare registers or inside memories. */
1429 for (i
= 0; i
< recog_data
.n_operands
; ++i
)
1431 x
= recog_data
.operand
[i
];
1432 switch (GET_CODE (x
))
1436 rtx addr
= XEXP (x
, 0);
1437 bool changed
= false;
1439 for_each_rtx (&addr
, instantiate_virtual_regs_in_rtx
, &changed
);
1444 x
= replace_equiv_address (x
, addr
);
1445 /* It may happen that the address with the virtual reg
1446 was valid (e.g. based on the virtual stack reg, which might
1447 be acceptable to the predicates with all offsets), whereas
1448 the address now isn't anymore, for instance when the address
1449 is still offsetted, but the base reg isn't virtual-stack-reg
1450 anymore. Below we would do a force_reg on the whole operand,
1451 but this insn might actually only accept memory. Hence,
1452 before doing that last resort, try to reload the address into
1453 a register, so this operand stays a MEM. */
1454 if (!safe_insn_predicate (insn_code
, i
, x
))
1456 addr
= force_reg (GET_MODE (addr
), addr
);
1457 x
= replace_equiv_address (x
, addr
);
1462 emit_insn_before (seq
, insn
);
1467 new_rtx
= instantiate_new_reg (x
, &offset
);
1468 if (new_rtx
== NULL
)
1476 /* Careful, special mode predicates may have stuff in
1477 insn_data[insn_code].operand[i].mode that isn't useful
1478 to us for computing a new value. */
1479 /* ??? Recognize address_operand and/or "p" constraints
1480 to see if (plus new offset) is a valid before we put
1481 this through expand_simple_binop. */
1482 x
= expand_simple_binop (GET_MODE (x
), PLUS
, new_rtx
,
1483 GEN_INT (offset
), NULL_RTX
,
1484 1, OPTAB_LIB_WIDEN
);
1487 emit_insn_before (seq
, insn
);
1492 new_rtx
= instantiate_new_reg (SUBREG_REG (x
), &offset
);
1493 if (new_rtx
== NULL
)
1498 new_rtx
= expand_simple_binop (GET_MODE (new_rtx
), PLUS
, new_rtx
,
1499 GEN_INT (offset
), NULL_RTX
,
1500 1, OPTAB_LIB_WIDEN
);
1503 emit_insn_before (seq
, insn
);
1505 x
= simplify_gen_subreg (recog_data
.operand_mode
[i
], new_rtx
,
1506 GET_MODE (new_rtx
), SUBREG_BYTE (x
));
1514 /* At this point, X contains the new value for the operand.
1515 Validate the new value vs the insn predicate. Note that
1516 asm insns will have insn_code -1 here. */
1517 if (!safe_insn_predicate (insn_code
, i
, x
))
1520 x
= force_reg (insn_data
[insn_code
].operand
[i
].mode
, x
);
1524 emit_insn_before (seq
, insn
);
1527 *recog_data
.operand_loc
[i
] = recog_data
.operand
[i
] = x
;
1533 /* Propagate operand changes into the duplicates. */
1534 for (i
= 0; i
< recog_data
.n_dups
; ++i
)
1535 *recog_data
.dup_loc
[i
]
1536 = copy_rtx (recog_data
.operand
[(unsigned)recog_data
.dup_num
[i
]]);
1538 /* Force re-recognition of the instruction for validation. */
1539 INSN_CODE (insn
) = -1;
1542 if (asm_noperands (PATTERN (insn
)) >= 0)
1544 if (!check_asm_operands (PATTERN (insn
)))
1546 error_for_asm (insn
, "impossible constraint in %<asm%>");
1552 if (recog_memoized (insn
) < 0)
1553 fatal_insn_not_found (insn
);
1557 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1558 do any instantiation required. */
1561 instantiate_decl_rtl (rtx x
)
1568 /* If this is a CONCAT, recurse for the pieces. */
1569 if (GET_CODE (x
) == CONCAT
)
1571 instantiate_decl_rtl (XEXP (x
, 0));
1572 instantiate_decl_rtl (XEXP (x
, 1));
1576 /* If this is not a MEM, no need to do anything. Similarly if the
1577 address is a constant or a register that is not a virtual register. */
1582 if (CONSTANT_P (addr
)
1584 && (REGNO (addr
) < FIRST_VIRTUAL_REGISTER
1585 || REGNO (addr
) > LAST_VIRTUAL_REGISTER
)))
1588 for_each_rtx (&XEXP (x
, 0), instantiate_virtual_regs_in_rtx
, NULL
);
1591 /* Helper for instantiate_decls called via walk_tree: Process all decls
1592 in the given DECL_VALUE_EXPR. */
1595 instantiate_expr (tree
*tp
, int *walk_subtrees
, void *data ATTRIBUTE_UNUSED
)
1601 if (DECL_P (t
) && DECL_RTL_SET_P (t
))
1602 instantiate_decl_rtl (DECL_RTL (t
));
1607 /* Subroutine of instantiate_decls: Process all decls in the given
1608 BLOCK node and all its subblocks. */
1611 instantiate_decls_1 (tree let
)
1615 for (t
= BLOCK_VARS (let
); t
; t
= TREE_CHAIN (t
))
1617 if (DECL_RTL_SET_P (t
))
1618 instantiate_decl_rtl (DECL_RTL (t
));
1619 if (TREE_CODE (t
) == VAR_DECL
&& DECL_HAS_VALUE_EXPR_P (t
))
1621 tree v
= DECL_VALUE_EXPR (t
);
1622 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1626 /* Process all subblocks. */
1627 for (t
= BLOCK_SUBBLOCKS (let
); t
; t
= BLOCK_CHAIN (t
))
1628 instantiate_decls_1 (t
);
1631 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1632 all virtual registers in their DECL_RTL's. */
1635 instantiate_decls (tree fndecl
)
1639 /* Process all parameters of the function. */
1640 for (decl
= DECL_ARGUMENTS (fndecl
); decl
; decl
= TREE_CHAIN (decl
))
1642 instantiate_decl_rtl (DECL_RTL (decl
));
1643 instantiate_decl_rtl (DECL_INCOMING_RTL (decl
));
1644 if (DECL_HAS_VALUE_EXPR_P (decl
))
1646 tree v
= DECL_VALUE_EXPR (decl
);
1647 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1651 /* Now process all variables defined in the function or its subblocks. */
1652 instantiate_decls_1 (DECL_INITIAL (fndecl
));
1655 /* Pass through the INSNS of function FNDECL and convert virtual register
1656 references to hard register references. */
1659 instantiate_virtual_regs (void)
1663 /* Compute the offsets to use for this function. */
1664 in_arg_offset
= FIRST_PARM_OFFSET (current_function_decl
);
1665 var_offset
= STARTING_FRAME_OFFSET
;
1666 dynamic_offset
= STACK_DYNAMIC_OFFSET (current_function_decl
);
1667 out_arg_offset
= STACK_POINTER_OFFSET
;
1668 #ifdef FRAME_POINTER_CFA_OFFSET
1669 cfa_offset
= FRAME_POINTER_CFA_OFFSET (current_function_decl
);
1671 cfa_offset
= ARG_POINTER_CFA_OFFSET (current_function_decl
);
1674 /* Initialize recognition, indicating that volatile is OK. */
1677 /* Scan through all the insns, instantiating every virtual register still
1679 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
1682 /* These patterns in the instruction stream can never be recognized.
1683 Fortunately, they shouldn't contain virtual registers either. */
1684 if (GET_CODE (PATTERN (insn
)) == USE
1685 || GET_CODE (PATTERN (insn
)) == CLOBBER
1686 || GET_CODE (PATTERN (insn
)) == ADDR_VEC
1687 || GET_CODE (PATTERN (insn
)) == ADDR_DIFF_VEC
1688 || GET_CODE (PATTERN (insn
)) == ASM_INPUT
)
1691 instantiate_virtual_regs_in_insn (insn
);
1693 if (INSN_DELETED_P (insn
))
1696 for_each_rtx (®_NOTES (insn
), instantiate_virtual_regs_in_rtx
, NULL
);
1698 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1699 if (GET_CODE (insn
) == CALL_INSN
)
1700 for_each_rtx (&CALL_INSN_FUNCTION_USAGE (insn
),
1701 instantiate_virtual_regs_in_rtx
, NULL
);
1704 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1705 instantiate_decls (current_function_decl
);
1707 targetm
.instantiate_decls ();
1709 /* Indicate that, from now on, assign_stack_local should use
1710 frame_pointer_rtx. */
1711 virtuals_instantiated
= 1;
1715 struct rtl_opt_pass pass_instantiate_virtual_regs
=
1721 instantiate_virtual_regs
, /* execute */
1724 0, /* static_pass_number */
1726 0, /* properties_required */
1727 0, /* properties_provided */
1728 0, /* properties_destroyed */
1729 0, /* todo_flags_start */
1730 TODO_dump_func
/* todo_flags_finish */
1735 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
1736 This means a type for which function calls must pass an address to the
1737 function or get an address back from the function.
1738 EXP may be a type node or an expression (whose type is tested). */
1741 aggregate_value_p (const_tree exp
, const_tree fntype
)
1743 int i
, regno
, nregs
;
1746 const_tree type
= (TYPE_P (exp
)) ? exp
: TREE_TYPE (exp
);
1748 /* DECL node associated with FNTYPE when relevant, which we might need to
1749 check for by-invisible-reference returns, typically for CALL_EXPR input
1751 const_tree fndecl
= NULL_TREE
;
1754 switch (TREE_CODE (fntype
))
1757 fndecl
= get_callee_fndecl (fntype
);
1758 fntype
= fndecl
? TREE_TYPE (fndecl
) : 0;
1762 fntype
= TREE_TYPE (fndecl
);
1767 case IDENTIFIER_NODE
:
1771 /* We don't expect other rtl types here. */
1775 if (TREE_CODE (type
) == VOID_TYPE
)
1778 /* If the front end has decided that this needs to be passed by
1779 reference, do so. */
1780 if ((TREE_CODE (exp
) == PARM_DECL
|| TREE_CODE (exp
) == RESULT_DECL
)
1781 && DECL_BY_REFERENCE (exp
))
1784 /* If the EXPression is a CALL_EXPR, honor DECL_BY_REFERENCE set on the
1785 called function RESULT_DECL, meaning the function returns in memory by
1786 invisible reference. This check lets front-ends not set TREE_ADDRESSABLE
1787 on the function type, which used to be the way to request such a return
1788 mechanism but might now be causing troubles at gimplification time if
1789 temporaries with the function type need to be created. */
1790 if (TREE_CODE (exp
) == CALL_EXPR
&& fndecl
&& DECL_RESULT (fndecl
)
1791 && DECL_BY_REFERENCE (DECL_RESULT (fndecl
)))
1794 if (targetm
.calls
.return_in_memory (type
, fntype
))
1796 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
1797 and thus can't be returned in registers. */
1798 if (TREE_ADDRESSABLE (type
))
1800 if (flag_pcc_struct_return
&& AGGREGATE_TYPE_P (type
))
1802 /* Make sure we have suitable call-clobbered regs to return
1803 the value in; if not, we must return it in memory. */
1804 reg
= hard_function_value (type
, 0, fntype
, 0);
1806 /* If we have something other than a REG (e.g. a PARALLEL), then assume
1811 regno
= REGNO (reg
);
1812 nregs
= hard_regno_nregs
[regno
][TYPE_MODE (type
)];
1813 for (i
= 0; i
< nregs
; i
++)
1814 if (! call_used_regs
[regno
+ i
])
1819 /* Return true if we should assign DECL a pseudo register; false if it
1820 should live on the local stack. */
1823 use_register_for_decl (const_tree decl
)
1825 if (!targetm
.calls
.allocate_stack_slots_for_args())
1828 /* Honor volatile. */
1829 if (TREE_SIDE_EFFECTS (decl
))
1832 /* Honor addressability. */
1833 if (TREE_ADDRESSABLE (decl
))
1836 /* Only register-like things go in registers. */
1837 if (DECL_MODE (decl
) == BLKmode
)
1840 /* If -ffloat-store specified, don't put explicit float variables
1842 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
1843 propagates values across these stores, and it probably shouldn't. */
1844 if (flag_float_store
&& FLOAT_TYPE_P (TREE_TYPE (decl
)))
1847 /* If we're not interested in tracking debugging information for
1848 this decl, then we can certainly put it in a register. */
1849 if (DECL_IGNORED_P (decl
))
1852 return (optimize
|| DECL_REGISTER (decl
));
1855 /* Return true if TYPE should be passed by invisible reference. */
1858 pass_by_reference (CUMULATIVE_ARGS
*ca
, enum machine_mode mode
,
1859 tree type
, bool named_arg
)
1863 /* If this type contains non-trivial constructors, then it is
1864 forbidden for the middle-end to create any new copies. */
1865 if (TREE_ADDRESSABLE (type
))
1868 /* GCC post 3.4 passes *all* variable sized types by reference. */
1869 if (!TYPE_SIZE (type
) || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
1873 return targetm
.calls
.pass_by_reference (ca
, mode
, type
, named_arg
);
1876 /* Return true if TYPE, which is passed by reference, should be callee
1877 copied instead of caller copied. */
1880 reference_callee_copied (CUMULATIVE_ARGS
*ca
, enum machine_mode mode
,
1881 tree type
, bool named_arg
)
1883 if (type
&& TREE_ADDRESSABLE (type
))
1885 return targetm
.calls
.callee_copies (ca
, mode
, type
, named_arg
);
1888 /* Structures to communicate between the subroutines of assign_parms.
1889 The first holds data persistent across all parameters, the second
1890 is cleared out for each parameter. */
1892 struct assign_parm_data_all
1894 CUMULATIVE_ARGS args_so_far
;
1895 struct args_size stack_args_size
;
1896 tree function_result_decl
;
1898 rtx first_conversion_insn
;
1899 rtx last_conversion_insn
;
1900 HOST_WIDE_INT pretend_args_size
;
1901 HOST_WIDE_INT extra_pretend_bytes
;
1902 int reg_parm_stack_space
;
1905 struct assign_parm_data_one
1911 enum machine_mode nominal_mode
;
1912 enum machine_mode passed_mode
;
1913 enum machine_mode promoted_mode
;
1914 struct locate_and_pad_arg_data locate
;
1916 BOOL_BITFIELD named_arg
: 1;
1917 BOOL_BITFIELD passed_pointer
: 1;
1918 BOOL_BITFIELD on_stack
: 1;
1919 BOOL_BITFIELD loaded_in_reg
: 1;
1922 /* A subroutine of assign_parms. Initialize ALL. */
1925 assign_parms_initialize_all (struct assign_parm_data_all
*all
)
1929 memset (all
, 0, sizeof (*all
));
1931 fntype
= TREE_TYPE (current_function_decl
);
1933 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
1934 INIT_CUMULATIVE_INCOMING_ARGS (all
->args_so_far
, fntype
, NULL_RTX
);
1936 INIT_CUMULATIVE_ARGS (all
->args_so_far
, fntype
, NULL_RTX
,
1937 current_function_decl
, -1);
1940 #ifdef REG_PARM_STACK_SPACE
1941 all
->reg_parm_stack_space
= REG_PARM_STACK_SPACE (current_function_decl
);
1945 /* If ARGS contains entries with complex types, split the entry into two
1946 entries of the component type. Return a new list of substitutions are
1947 needed, else the old list. */
1950 split_complex_args (tree args
)
1954 /* Before allocating memory, check for the common case of no complex. */
1955 for (p
= args
; p
; p
= TREE_CHAIN (p
))
1957 tree type
= TREE_TYPE (p
);
1958 if (TREE_CODE (type
) == COMPLEX_TYPE
1959 && targetm
.calls
.split_complex_arg (type
))
1965 args
= copy_list (args
);
1967 for (p
= args
; p
; p
= TREE_CHAIN (p
))
1969 tree type
= TREE_TYPE (p
);
1970 if (TREE_CODE (type
) == COMPLEX_TYPE
1971 && targetm
.calls
.split_complex_arg (type
))
1974 tree subtype
= TREE_TYPE (type
);
1975 bool addressable
= TREE_ADDRESSABLE (p
);
1977 /* Rewrite the PARM_DECL's type with its component. */
1978 TREE_TYPE (p
) = subtype
;
1979 DECL_ARG_TYPE (p
) = TREE_TYPE (DECL_ARG_TYPE (p
));
1980 DECL_MODE (p
) = VOIDmode
;
1981 DECL_SIZE (p
) = NULL
;
1982 DECL_SIZE_UNIT (p
) = NULL
;
1983 /* If this arg must go in memory, put it in a pseudo here.
1984 We can't allow it to go in memory as per normal parms,
1985 because the usual place might not have the imag part
1986 adjacent to the real part. */
1987 DECL_ARTIFICIAL (p
) = addressable
;
1988 DECL_IGNORED_P (p
) = addressable
;
1989 TREE_ADDRESSABLE (p
) = 0;
1992 /* Build a second synthetic decl. */
1993 decl
= build_decl (PARM_DECL
, NULL_TREE
, subtype
);
1994 DECL_ARG_TYPE (decl
) = DECL_ARG_TYPE (p
);
1995 DECL_ARTIFICIAL (decl
) = addressable
;
1996 DECL_IGNORED_P (decl
) = addressable
;
1997 layout_decl (decl
, 0);
1999 /* Splice it in; skip the new decl. */
2000 TREE_CHAIN (decl
) = TREE_CHAIN (p
);
2001 TREE_CHAIN (p
) = decl
;
2009 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
2010 the hidden struct return argument, and (abi willing) complex args.
2011 Return the new parameter list. */
2014 assign_parms_augmented_arg_list (struct assign_parm_data_all
*all
)
2016 tree fndecl
= current_function_decl
;
2017 tree fntype
= TREE_TYPE (fndecl
);
2018 tree fnargs
= DECL_ARGUMENTS (fndecl
);
2020 /* If struct value address is treated as the first argument, make it so. */
2021 if (aggregate_value_p (DECL_RESULT (fndecl
), fndecl
)
2022 && ! cfun
->returns_pcc_struct
2023 && targetm
.calls
.struct_value_rtx (TREE_TYPE (fndecl
), 1) == 0)
2025 tree type
= build_pointer_type (TREE_TYPE (fntype
));
2028 decl
= build_decl (PARM_DECL
, NULL_TREE
, type
);
2029 DECL_ARG_TYPE (decl
) = type
;
2030 DECL_ARTIFICIAL (decl
) = 1;
2031 DECL_IGNORED_P (decl
) = 1;
2033 TREE_CHAIN (decl
) = fnargs
;
2035 all
->function_result_decl
= decl
;
2038 all
->orig_fnargs
= fnargs
;
2040 /* If the target wants to split complex arguments into scalars, do so. */
2041 if (targetm
.calls
.split_complex_arg
)
2042 fnargs
= split_complex_args (fnargs
);
2047 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2048 data for the parameter. Incorporate ABI specifics such as pass-by-
2049 reference and type promotion. */
2052 assign_parm_find_data_types (struct assign_parm_data_all
*all
, tree parm
,
2053 struct assign_parm_data_one
*data
)
2055 tree nominal_type
, passed_type
;
2056 enum machine_mode nominal_mode
, passed_mode
, promoted_mode
;
2058 memset (data
, 0, sizeof (*data
));
2060 /* NAMED_ARG is a misnomer. We really mean 'non-variadic'. */
2062 data
->named_arg
= 1; /* No variadic parms. */
2063 else if (TREE_CHAIN (parm
))
2064 data
->named_arg
= 1; /* Not the last non-variadic parm. */
2065 else if (targetm
.calls
.strict_argument_naming (&all
->args_so_far
))
2066 data
->named_arg
= 1; /* Only variadic ones are unnamed. */
2068 data
->named_arg
= 0; /* Treat as variadic. */
2070 nominal_type
= TREE_TYPE (parm
);
2071 passed_type
= DECL_ARG_TYPE (parm
);
2073 /* Look out for errors propagating this far. Also, if the parameter's
2074 type is void then its value doesn't matter. */
2075 if (TREE_TYPE (parm
) == error_mark_node
2076 /* This can happen after weird syntax errors
2077 or if an enum type is defined among the parms. */
2078 || TREE_CODE (parm
) != PARM_DECL
2079 || passed_type
== NULL
2080 || VOID_TYPE_P (nominal_type
))
2082 nominal_type
= passed_type
= void_type_node
;
2083 nominal_mode
= passed_mode
= promoted_mode
= VOIDmode
;
2087 /* Find mode of arg as it is passed, and mode of arg as it should be
2088 during execution of this function. */
2089 passed_mode
= TYPE_MODE (passed_type
);
2090 nominal_mode
= TYPE_MODE (nominal_type
);
2092 /* If the parm is to be passed as a transparent union, use the type of
2093 the first field for the tests below. We have already verified that
2094 the modes are the same. */
2095 if (TREE_CODE (passed_type
) == UNION_TYPE
2096 && TYPE_TRANSPARENT_UNION (passed_type
))
2097 passed_type
= TREE_TYPE (TYPE_FIELDS (passed_type
));
2099 /* See if this arg was passed by invisible reference. */
2100 if (pass_by_reference (&all
->args_so_far
, passed_mode
,
2101 passed_type
, data
->named_arg
))
2103 passed_type
= nominal_type
= build_pointer_type (passed_type
);
2104 data
->passed_pointer
= true;
2105 passed_mode
= nominal_mode
= Pmode
;
2108 /* Find mode as it is passed by the ABI. */
2109 promoted_mode
= passed_mode
;
2110 if (targetm
.calls
.promote_function_args (TREE_TYPE (current_function_decl
)))
2112 int unsignedp
= TYPE_UNSIGNED (passed_type
);
2113 promoted_mode
= promote_mode (passed_type
, promoted_mode
,
2118 data
->nominal_type
= nominal_type
;
2119 data
->passed_type
= passed_type
;
2120 data
->nominal_mode
= nominal_mode
;
2121 data
->passed_mode
= passed_mode
;
2122 data
->promoted_mode
= promoted_mode
;
2125 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2128 assign_parms_setup_varargs (struct assign_parm_data_all
*all
,
2129 struct assign_parm_data_one
*data
, bool no_rtl
)
2131 int varargs_pretend_bytes
= 0;
2133 targetm
.calls
.setup_incoming_varargs (&all
->args_so_far
,
2134 data
->promoted_mode
,
2136 &varargs_pretend_bytes
, no_rtl
);
2138 /* If the back-end has requested extra stack space, record how much is
2139 needed. Do not change pretend_args_size otherwise since it may be
2140 nonzero from an earlier partial argument. */
2141 if (varargs_pretend_bytes
> 0)
2142 all
->pretend_args_size
= varargs_pretend_bytes
;
2145 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2146 the incoming location of the current parameter. */
2149 assign_parm_find_entry_rtl (struct assign_parm_data_all
*all
,
2150 struct assign_parm_data_one
*data
)
2152 HOST_WIDE_INT pretend_bytes
= 0;
2156 if (data
->promoted_mode
== VOIDmode
)
2158 data
->entry_parm
= data
->stack_parm
= const0_rtx
;
2162 #ifdef FUNCTION_INCOMING_ARG
2163 entry_parm
= FUNCTION_INCOMING_ARG (all
->args_so_far
, data
->promoted_mode
,
2164 data
->passed_type
, data
->named_arg
);
2166 entry_parm
= FUNCTION_ARG (all
->args_so_far
, data
->promoted_mode
,
2167 data
->passed_type
, data
->named_arg
);
2170 if (entry_parm
== 0)
2171 data
->promoted_mode
= data
->passed_mode
;
2173 /* Determine parm's home in the stack, in case it arrives in the stack
2174 or we should pretend it did. Compute the stack position and rtx where
2175 the argument arrives and its size.
2177 There is one complexity here: If this was a parameter that would
2178 have been passed in registers, but wasn't only because it is
2179 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2180 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2181 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2182 as it was the previous time. */
2183 in_regs
= entry_parm
!= 0;
2184 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2187 if (!in_regs
&& !data
->named_arg
)
2189 if (targetm
.calls
.pretend_outgoing_varargs_named (&all
->args_so_far
))
2192 #ifdef FUNCTION_INCOMING_ARG
2193 tem
= FUNCTION_INCOMING_ARG (all
->args_so_far
, data
->promoted_mode
,
2194 data
->passed_type
, true);
2196 tem
= FUNCTION_ARG (all
->args_so_far
, data
->promoted_mode
,
2197 data
->passed_type
, true);
2199 in_regs
= tem
!= NULL
;
2203 /* If this parameter was passed both in registers and in the stack, use
2204 the copy on the stack. */
2205 if (targetm
.calls
.must_pass_in_stack (data
->promoted_mode
,
2213 partial
= targetm
.calls
.arg_partial_bytes (&all
->args_so_far
,
2214 data
->promoted_mode
,
2217 data
->partial
= partial
;
2219 /* The caller might already have allocated stack space for the
2220 register parameters. */
2221 if (partial
!= 0 && all
->reg_parm_stack_space
== 0)
2223 /* Part of this argument is passed in registers and part
2224 is passed on the stack. Ask the prologue code to extend
2225 the stack part so that we can recreate the full value.
2227 PRETEND_BYTES is the size of the registers we need to store.
2228 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2229 stack space that the prologue should allocate.
2231 Internally, gcc assumes that the argument pointer is aligned
2232 to STACK_BOUNDARY bits. This is used both for alignment
2233 optimizations (see init_emit) and to locate arguments that are
2234 aligned to more than PARM_BOUNDARY bits. We must preserve this
2235 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2236 a stack boundary. */
2238 /* We assume at most one partial arg, and it must be the first
2239 argument on the stack. */
2240 gcc_assert (!all
->extra_pretend_bytes
&& !all
->pretend_args_size
);
2242 pretend_bytes
= partial
;
2243 all
->pretend_args_size
= CEIL_ROUND (pretend_bytes
, STACK_BYTES
);
2245 /* We want to align relative to the actual stack pointer, so
2246 don't include this in the stack size until later. */
2247 all
->extra_pretend_bytes
= all
->pretend_args_size
;
2251 locate_and_pad_parm (data
->promoted_mode
, data
->passed_type
, in_regs
,
2252 entry_parm
? data
->partial
: 0, current_function_decl
,
2253 &all
->stack_args_size
, &data
->locate
);
2255 /* Update parm_stack_boundary if this parameter is passed in the
2257 if (!in_regs
&& crtl
->parm_stack_boundary
< data
->locate
.boundary
)
2258 crtl
->parm_stack_boundary
= data
->locate
.boundary
;
2260 /* Adjust offsets to include the pretend args. */
2261 pretend_bytes
= all
->extra_pretend_bytes
- pretend_bytes
;
2262 data
->locate
.slot_offset
.constant
+= pretend_bytes
;
2263 data
->locate
.offset
.constant
+= pretend_bytes
;
2265 data
->entry_parm
= entry_parm
;
2268 /* A subroutine of assign_parms. If there is actually space on the stack
2269 for this parm, count it in stack_args_size and return true. */
2272 assign_parm_is_stack_parm (struct assign_parm_data_all
*all
,
2273 struct assign_parm_data_one
*data
)
2275 /* Trivially true if we've no incoming register. */
2276 if (data
->entry_parm
== NULL
)
2278 /* Also true if we're partially in registers and partially not,
2279 since we've arranged to drop the entire argument on the stack. */
2280 else if (data
->partial
!= 0)
2282 /* Also true if the target says that it's passed in both registers
2283 and on the stack. */
2284 else if (GET_CODE (data
->entry_parm
) == PARALLEL
2285 && XEXP (XVECEXP (data
->entry_parm
, 0, 0), 0) == NULL_RTX
)
2287 /* Also true if the target says that there's stack allocated for
2288 all register parameters. */
2289 else if (all
->reg_parm_stack_space
> 0)
2291 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2295 all
->stack_args_size
.constant
+= data
->locate
.size
.constant
;
2296 if (data
->locate
.size
.var
)
2297 ADD_PARM_SIZE (all
->stack_args_size
, data
->locate
.size
.var
);
2302 /* A subroutine of assign_parms. Given that this parameter is allocated
2303 stack space by the ABI, find it. */
2306 assign_parm_find_stack_rtl (tree parm
, struct assign_parm_data_one
*data
)
2308 rtx offset_rtx
, stack_parm
;
2309 unsigned int align
, boundary
;
2311 /* If we're passing this arg using a reg, make its stack home the
2312 aligned stack slot. */
2313 if (data
->entry_parm
)
2314 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.slot_offset
);
2316 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.offset
);
2318 stack_parm
= crtl
->args
.internal_arg_pointer
;
2319 if (offset_rtx
!= const0_rtx
)
2320 stack_parm
= gen_rtx_PLUS (Pmode
, stack_parm
, offset_rtx
);
2321 stack_parm
= gen_rtx_MEM (data
->promoted_mode
, stack_parm
);
2323 set_mem_attributes (stack_parm
, parm
, 1);
2324 /* set_mem_attributes could set MEM_SIZE to the passed mode's size,
2325 while promoted mode's size is needed. */
2326 if (data
->promoted_mode
!= BLKmode
2327 && data
->promoted_mode
!= DECL_MODE (parm
))
2328 set_mem_size (stack_parm
, GEN_INT (GET_MODE_SIZE (data
->promoted_mode
)));
2330 boundary
= data
->locate
.boundary
;
2331 align
= BITS_PER_UNIT
;
2333 /* If we're padding upward, we know that the alignment of the slot
2334 is FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2335 intentionally forcing upward padding. Otherwise we have to come
2336 up with a guess at the alignment based on OFFSET_RTX. */
2337 if (data
->locate
.where_pad
!= downward
|| data
->entry_parm
)
2339 else if (GET_CODE (offset_rtx
) == CONST_INT
)
2341 align
= INTVAL (offset_rtx
) * BITS_PER_UNIT
| boundary
;
2342 align
= align
& -align
;
2344 set_mem_align (stack_parm
, align
);
2346 if (data
->entry_parm
)
2347 set_reg_attrs_for_parm (data
->entry_parm
, stack_parm
);
2349 data
->stack_parm
= stack_parm
;
2352 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2353 always valid and contiguous. */
2356 assign_parm_adjust_entry_rtl (struct assign_parm_data_one
*data
)
2358 rtx entry_parm
= data
->entry_parm
;
2359 rtx stack_parm
= data
->stack_parm
;
2361 /* If this parm was passed part in regs and part in memory, pretend it
2362 arrived entirely in memory by pushing the register-part onto the stack.
2363 In the special case of a DImode or DFmode that is split, we could put
2364 it together in a pseudoreg directly, but for now that's not worth
2366 if (data
->partial
!= 0)
2368 /* Handle calls that pass values in multiple non-contiguous
2369 locations. The Irix 6 ABI has examples of this. */
2370 if (GET_CODE (entry_parm
) == PARALLEL
)
2371 emit_group_store (validize_mem (stack_parm
), entry_parm
,
2373 int_size_in_bytes (data
->passed_type
));
2376 gcc_assert (data
->partial
% UNITS_PER_WORD
== 0);
2377 move_block_from_reg (REGNO (entry_parm
), validize_mem (stack_parm
),
2378 data
->partial
/ UNITS_PER_WORD
);
2381 entry_parm
= stack_parm
;
2384 /* If we didn't decide this parm came in a register, by default it came
2386 else if (entry_parm
== NULL
)
2387 entry_parm
= stack_parm
;
2389 /* When an argument is passed in multiple locations, we can't make use
2390 of this information, but we can save some copying if the whole argument
2391 is passed in a single register. */
2392 else if (GET_CODE (entry_parm
) == PARALLEL
2393 && data
->nominal_mode
!= BLKmode
2394 && data
->passed_mode
!= BLKmode
)
2396 size_t i
, len
= XVECLEN (entry_parm
, 0);
2398 for (i
= 0; i
< len
; i
++)
2399 if (XEXP (XVECEXP (entry_parm
, 0, i
), 0) != NULL_RTX
2400 && REG_P (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2401 && (GET_MODE (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2402 == data
->passed_mode
)
2403 && INTVAL (XEXP (XVECEXP (entry_parm
, 0, i
), 1)) == 0)
2405 entry_parm
= XEXP (XVECEXP (entry_parm
, 0, i
), 0);
2410 data
->entry_parm
= entry_parm
;
2413 /* A subroutine of assign_parms. Reconstitute any values which were
2414 passed in multiple registers and would fit in a single register. */
2417 assign_parm_remove_parallels (struct assign_parm_data_one
*data
)
2419 rtx entry_parm
= data
->entry_parm
;
2421 /* Convert the PARALLEL to a REG of the same mode as the parallel.
2422 This can be done with register operations rather than on the
2423 stack, even if we will store the reconstituted parameter on the
2425 if (GET_CODE (entry_parm
) == PARALLEL
&& GET_MODE (entry_parm
) != BLKmode
)
2427 rtx parmreg
= gen_reg_rtx (GET_MODE (entry_parm
));
2428 emit_group_store (parmreg
, entry_parm
, NULL_TREE
,
2429 GET_MODE_SIZE (GET_MODE (entry_parm
)));
2430 entry_parm
= parmreg
;
2433 data
->entry_parm
= entry_parm
;
2436 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2437 always valid and properly aligned. */
2440 assign_parm_adjust_stack_rtl (struct assign_parm_data_one
*data
)
2442 rtx stack_parm
= data
->stack_parm
;
2444 /* If we can't trust the parm stack slot to be aligned enough for its
2445 ultimate type, don't use that slot after entry. We'll make another
2446 stack slot, if we need one. */
2448 && ((STRICT_ALIGNMENT
2449 && GET_MODE_ALIGNMENT (data
->nominal_mode
) > MEM_ALIGN (stack_parm
))
2450 || (data
->nominal_type
2451 && TYPE_ALIGN (data
->nominal_type
) > MEM_ALIGN (stack_parm
)
2452 && MEM_ALIGN (stack_parm
) < PREFERRED_STACK_BOUNDARY
)))
2455 /* If parm was passed in memory, and we need to convert it on entry,
2456 don't store it back in that same slot. */
2457 else if (data
->entry_parm
== stack_parm
2458 && data
->nominal_mode
!= BLKmode
2459 && data
->nominal_mode
!= data
->passed_mode
)
2462 /* If stack protection is in effect for this function, don't leave any
2463 pointers in their passed stack slots. */
2464 else if (crtl
->stack_protect_guard
2465 && (flag_stack_protect
== 2
2466 || data
->passed_pointer
2467 || POINTER_TYPE_P (data
->nominal_type
)))
2470 data
->stack_parm
= stack_parm
;
2473 /* A subroutine of assign_parms. Return true if the current parameter
2474 should be stored as a BLKmode in the current frame. */
2477 assign_parm_setup_block_p (struct assign_parm_data_one
*data
)
2479 if (data
->nominal_mode
== BLKmode
)
2481 if (GET_MODE (data
->entry_parm
) == BLKmode
)
2484 #ifdef BLOCK_REG_PADDING
2485 /* Only assign_parm_setup_block knows how to deal with register arguments
2486 that are padded at the least significant end. */
2487 if (REG_P (data
->entry_parm
)
2488 && GET_MODE_SIZE (data
->promoted_mode
) < UNITS_PER_WORD
2489 && (BLOCK_REG_PADDING (data
->passed_mode
, data
->passed_type
, 1)
2490 == (BYTES_BIG_ENDIAN
? upward
: downward
)))
2497 /* A subroutine of assign_parms. Arrange for the parameter to be
2498 present and valid in DATA->STACK_RTL. */
2501 assign_parm_setup_block (struct assign_parm_data_all
*all
,
2502 tree parm
, struct assign_parm_data_one
*data
)
2504 rtx entry_parm
= data
->entry_parm
;
2505 rtx stack_parm
= data
->stack_parm
;
2507 HOST_WIDE_INT size_stored
;
2509 if (GET_CODE (entry_parm
) == PARALLEL
)
2510 entry_parm
= emit_group_move_into_temps (entry_parm
);
2512 size
= int_size_in_bytes (data
->passed_type
);
2513 size_stored
= CEIL_ROUND (size
, UNITS_PER_WORD
);
2514 if (stack_parm
== 0)
2516 DECL_ALIGN (parm
) = MAX (DECL_ALIGN (parm
), BITS_PER_WORD
);
2517 stack_parm
= assign_stack_local (BLKmode
, size_stored
,
2519 if (GET_MODE_SIZE (GET_MODE (entry_parm
)) == size
)
2520 PUT_MODE (stack_parm
, GET_MODE (entry_parm
));
2521 set_mem_attributes (stack_parm
, parm
, 1);
2524 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2525 calls that pass values in multiple non-contiguous locations. */
2526 if (REG_P (entry_parm
) || GET_CODE (entry_parm
) == PARALLEL
)
2530 /* Note that we will be storing an integral number of words.
2531 So we have to be careful to ensure that we allocate an
2532 integral number of words. We do this above when we call
2533 assign_stack_local if space was not allocated in the argument
2534 list. If it was, this will not work if PARM_BOUNDARY is not
2535 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2536 if it becomes a problem. Exception is when BLKmode arrives
2537 with arguments not conforming to word_mode. */
2539 if (data
->stack_parm
== 0)
2541 else if (GET_CODE (entry_parm
) == PARALLEL
)
2544 gcc_assert (!size
|| !(PARM_BOUNDARY
% BITS_PER_WORD
));
2546 mem
= validize_mem (stack_parm
);
2548 /* Handle values in multiple non-contiguous locations. */
2549 if (GET_CODE (entry_parm
) == PARALLEL
)
2551 push_to_sequence2 (all
->first_conversion_insn
,
2552 all
->last_conversion_insn
);
2553 emit_group_store (mem
, entry_parm
, data
->passed_type
, size
);
2554 all
->first_conversion_insn
= get_insns ();
2555 all
->last_conversion_insn
= get_last_insn ();
2562 /* If SIZE is that of a mode no bigger than a word, just use
2563 that mode's store operation. */
2564 else if (size
<= UNITS_PER_WORD
)
2566 enum machine_mode mode
2567 = mode_for_size (size
* BITS_PER_UNIT
, MODE_INT
, 0);
2570 #ifdef BLOCK_REG_PADDING
2571 && (size
== UNITS_PER_WORD
2572 || (BLOCK_REG_PADDING (mode
, data
->passed_type
, 1)
2573 != (BYTES_BIG_ENDIAN
? upward
: downward
)))
2579 /* We are really truncating a word_mode value containing
2580 SIZE bytes into a value of mode MODE. If such an
2581 operation requires no actual instructions, we can refer
2582 to the value directly in mode MODE, otherwise we must
2583 start with the register in word_mode and explicitly
2585 if (TRULY_NOOP_TRUNCATION (size
* BITS_PER_UNIT
, BITS_PER_WORD
))
2586 reg
= gen_rtx_REG (mode
, REGNO (entry_parm
));
2589 reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
2590 reg
= convert_to_mode (mode
, copy_to_reg (reg
), 1);
2592 emit_move_insn (change_address (mem
, mode
, 0), reg
);
2595 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
2596 machine must be aligned to the left before storing
2597 to memory. Note that the previous test doesn't
2598 handle all cases (e.g. SIZE == 3). */
2599 else if (size
!= UNITS_PER_WORD
2600 #ifdef BLOCK_REG_PADDING
2601 && (BLOCK_REG_PADDING (mode
, data
->passed_type
, 1)
2609 int by
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
2610 rtx reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
2612 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
,
2613 build_int_cst (NULL_TREE
, by
),
2615 tem
= change_address (mem
, word_mode
, 0);
2616 emit_move_insn (tem
, x
);
2619 move_block_from_reg (REGNO (entry_parm
), mem
,
2620 size_stored
/ UNITS_PER_WORD
);
2623 move_block_from_reg (REGNO (entry_parm
), mem
,
2624 size_stored
/ UNITS_PER_WORD
);
2626 else if (data
->stack_parm
== 0)
2628 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2629 emit_block_move (stack_parm
, data
->entry_parm
, GEN_INT (size
),
2631 all
->first_conversion_insn
= get_insns ();
2632 all
->last_conversion_insn
= get_last_insn ();
2636 data
->stack_parm
= stack_parm
;
2637 SET_DECL_RTL (parm
, stack_parm
);
2640 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
2641 parameter. Get it there. Perform all ABI specified conversions. */
2644 assign_parm_setup_reg (struct assign_parm_data_all
*all
, tree parm
,
2645 struct assign_parm_data_one
*data
)
2648 enum machine_mode promoted_nominal_mode
;
2649 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (parm
));
2650 bool did_conversion
= false;
2652 /* Store the parm in a pseudoregister during the function, but we may
2653 need to do it in a wider mode. */
2655 /* This is not really promoting for a call. However we need to be
2656 consistent with assign_parm_find_data_types and expand_expr_real_1. */
2657 promoted_nominal_mode
2658 = promote_mode (data
->nominal_type
, data
->nominal_mode
, &unsignedp
, 1);
2660 parmreg
= gen_reg_rtx (promoted_nominal_mode
);
2662 if (!DECL_ARTIFICIAL (parm
))
2663 mark_user_reg (parmreg
);
2665 /* If this was an item that we received a pointer to,
2666 set DECL_RTL appropriately. */
2667 if (data
->passed_pointer
)
2669 rtx x
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data
->passed_type
)), parmreg
);
2670 set_mem_attributes (x
, parm
, 1);
2671 SET_DECL_RTL (parm
, x
);
2674 SET_DECL_RTL (parm
, parmreg
);
2676 assign_parm_remove_parallels (data
);
2678 /* Copy the value into the register. */
2679 if (data
->nominal_mode
!= data
->passed_mode
2680 || promoted_nominal_mode
!= data
->promoted_mode
)
2684 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
2685 mode, by the caller. We now have to convert it to
2686 NOMINAL_MODE, if different. However, PARMREG may be in
2687 a different mode than NOMINAL_MODE if it is being stored
2690 If ENTRY_PARM is a hard register, it might be in a register
2691 not valid for operating in its mode (e.g., an odd-numbered
2692 register for a DFmode). In that case, moves are the only
2693 thing valid, so we can't do a convert from there. This
2694 occurs when the calling sequence allow such misaligned
2697 In addition, the conversion may involve a call, which could
2698 clobber parameters which haven't been copied to pseudo
2699 registers yet. Therefore, we must first copy the parm to
2700 a pseudo reg here, and save the conversion until after all
2701 parameters have been moved. */
2703 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
2705 emit_move_insn (tempreg
, validize_mem (data
->entry_parm
));
2707 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2708 tempreg
= convert_to_mode (data
->nominal_mode
, tempreg
, unsignedp
);
2710 if (GET_CODE (tempreg
) == SUBREG
2711 && GET_MODE (tempreg
) == data
->nominal_mode
2712 && REG_P (SUBREG_REG (tempreg
))
2713 && data
->nominal_mode
== data
->passed_mode
2714 && GET_MODE (SUBREG_REG (tempreg
)) == GET_MODE (data
->entry_parm
)
2715 && GET_MODE_SIZE (GET_MODE (tempreg
))
2716 < GET_MODE_SIZE (GET_MODE (data
->entry_parm
)))
2718 /* The argument is already sign/zero extended, so note it
2720 SUBREG_PROMOTED_VAR_P (tempreg
) = 1;
2721 SUBREG_PROMOTED_UNSIGNED_SET (tempreg
, unsignedp
);
2724 /* TREE_USED gets set erroneously during expand_assignment. */
2725 save_tree_used
= TREE_USED (parm
);
2726 expand_assignment (parm
, make_tree (data
->nominal_type
, tempreg
), false);
2727 TREE_USED (parm
) = save_tree_used
;
2728 all
->first_conversion_insn
= get_insns ();
2729 all
->last_conversion_insn
= get_last_insn ();
2732 did_conversion
= true;
2735 emit_move_insn (parmreg
, validize_mem (data
->entry_parm
));
2737 /* If we were passed a pointer but the actual value can safely live
2738 in a register, put it in one. */
2739 if (data
->passed_pointer
2740 && TYPE_MODE (TREE_TYPE (parm
)) != BLKmode
2741 /* If by-reference argument was promoted, demote it. */
2742 && (TYPE_MODE (TREE_TYPE (parm
)) != GET_MODE (DECL_RTL (parm
))
2743 || use_register_for_decl (parm
)))
2745 /* We can't use nominal_mode, because it will have been set to
2746 Pmode above. We must use the actual mode of the parm. */
2747 parmreg
= gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm
)));
2748 mark_user_reg (parmreg
);
2750 if (GET_MODE (parmreg
) != GET_MODE (DECL_RTL (parm
)))
2752 rtx tempreg
= gen_reg_rtx (GET_MODE (DECL_RTL (parm
)));
2753 int unsigned_p
= TYPE_UNSIGNED (TREE_TYPE (parm
));
2755 push_to_sequence2 (all
->first_conversion_insn
,
2756 all
->last_conversion_insn
);
2757 emit_move_insn (tempreg
, DECL_RTL (parm
));
2758 tempreg
= convert_to_mode (GET_MODE (parmreg
), tempreg
, unsigned_p
);
2759 emit_move_insn (parmreg
, tempreg
);
2760 all
->first_conversion_insn
= get_insns ();
2761 all
->last_conversion_insn
= get_last_insn ();
2764 did_conversion
= true;
2767 emit_move_insn (parmreg
, DECL_RTL (parm
));
2769 SET_DECL_RTL (parm
, parmreg
);
2771 /* STACK_PARM is the pointer, not the parm, and PARMREG is
2773 data
->stack_parm
= NULL
;
2776 /* Mark the register as eliminable if we did no conversion and it was
2777 copied from memory at a fixed offset, and the arg pointer was not
2778 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
2779 offset formed an invalid address, such memory-equivalences as we
2780 make here would screw up life analysis for it. */
2781 if (data
->nominal_mode
== data
->passed_mode
2783 && data
->stack_parm
!= 0
2784 && MEM_P (data
->stack_parm
)
2785 && data
->locate
.offset
.var
== 0
2786 && reg_mentioned_p (virtual_incoming_args_rtx
,
2787 XEXP (data
->stack_parm
, 0)))
2789 rtx linsn
= get_last_insn ();
2792 /* Mark complex types separately. */
2793 if (GET_CODE (parmreg
) == CONCAT
)
2795 enum machine_mode submode
2796 = GET_MODE_INNER (GET_MODE (parmreg
));
2797 int regnor
= REGNO (XEXP (parmreg
, 0));
2798 int regnoi
= REGNO (XEXP (parmreg
, 1));
2799 rtx stackr
= adjust_address_nv (data
->stack_parm
, submode
, 0);
2800 rtx stacki
= adjust_address_nv (data
->stack_parm
, submode
,
2801 GET_MODE_SIZE (submode
));
2803 /* Scan backwards for the set of the real and
2805 for (sinsn
= linsn
; sinsn
!= 0;
2806 sinsn
= prev_nonnote_insn (sinsn
))
2808 set
= single_set (sinsn
);
2812 if (SET_DEST (set
) == regno_reg_rtx
[regnoi
])
2813 set_unique_reg_note (sinsn
, REG_EQUIV
, stacki
);
2814 else if (SET_DEST (set
) == regno_reg_rtx
[regnor
])
2815 set_unique_reg_note (sinsn
, REG_EQUIV
, stackr
);
2818 else if ((set
= single_set (linsn
)) != 0
2819 && SET_DEST (set
) == parmreg
)
2820 set_unique_reg_note (linsn
, REG_EQUIV
, data
->stack_parm
);
2823 /* For pointer data type, suggest pointer register. */
2824 if (POINTER_TYPE_P (TREE_TYPE (parm
)))
2825 mark_reg_pointer (parmreg
,
2826 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
2829 /* A subroutine of assign_parms. Allocate stack space to hold the current
2830 parameter. Get it there. Perform all ABI specified conversions. */
2833 assign_parm_setup_stack (struct assign_parm_data_all
*all
, tree parm
,
2834 struct assign_parm_data_one
*data
)
2836 /* Value must be stored in the stack slot STACK_PARM during function
2838 bool to_conversion
= false;
2840 assign_parm_remove_parallels (data
);
2842 if (data
->promoted_mode
!= data
->nominal_mode
)
2844 /* Conversion is required. */
2845 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
2847 emit_move_insn (tempreg
, validize_mem (data
->entry_parm
));
2849 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2850 to_conversion
= true;
2852 data
->entry_parm
= convert_to_mode (data
->nominal_mode
, tempreg
,
2853 TYPE_UNSIGNED (TREE_TYPE (parm
)));
2855 if (data
->stack_parm
)
2856 /* ??? This may need a big-endian conversion on sparc64. */
2858 = adjust_address (data
->stack_parm
, data
->nominal_mode
, 0);
2861 if (data
->entry_parm
!= data
->stack_parm
)
2865 if (data
->stack_parm
== 0)
2868 = assign_stack_local (GET_MODE (data
->entry_parm
),
2869 GET_MODE_SIZE (GET_MODE (data
->entry_parm
)),
2870 TYPE_ALIGN (data
->passed_type
));
2871 set_mem_attributes (data
->stack_parm
, parm
, 1);
2874 dest
= validize_mem (data
->stack_parm
);
2875 src
= validize_mem (data
->entry_parm
);
2879 /* Use a block move to handle potentially misaligned entry_parm. */
2881 push_to_sequence2 (all
->first_conversion_insn
,
2882 all
->last_conversion_insn
);
2883 to_conversion
= true;
2885 emit_block_move (dest
, src
,
2886 GEN_INT (int_size_in_bytes (data
->passed_type
)),
2890 emit_move_insn (dest
, src
);
2895 all
->first_conversion_insn
= get_insns ();
2896 all
->last_conversion_insn
= get_last_insn ();
2900 SET_DECL_RTL (parm
, data
->stack_parm
);
2903 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
2904 undo the frobbing that we did in assign_parms_augmented_arg_list. */
2907 assign_parms_unsplit_complex (struct assign_parm_data_all
*all
, tree fnargs
)
2910 tree orig_fnargs
= all
->orig_fnargs
;
2912 for (parm
= orig_fnargs
; parm
; parm
= TREE_CHAIN (parm
))
2914 if (TREE_CODE (TREE_TYPE (parm
)) == COMPLEX_TYPE
2915 && targetm
.calls
.split_complex_arg (TREE_TYPE (parm
)))
2917 rtx tmp
, real
, imag
;
2918 enum machine_mode inner
= GET_MODE_INNER (DECL_MODE (parm
));
2920 real
= DECL_RTL (fnargs
);
2921 imag
= DECL_RTL (TREE_CHAIN (fnargs
));
2922 if (inner
!= GET_MODE (real
))
2924 real
= gen_lowpart_SUBREG (inner
, real
);
2925 imag
= gen_lowpart_SUBREG (inner
, imag
);
2928 if (TREE_ADDRESSABLE (parm
))
2931 HOST_WIDE_INT size
= int_size_in_bytes (TREE_TYPE (parm
));
2933 /* split_complex_arg put the real and imag parts in
2934 pseudos. Move them to memory. */
2935 tmp
= assign_stack_local (DECL_MODE (parm
), size
,
2936 TYPE_ALIGN (TREE_TYPE (parm
)));
2937 set_mem_attributes (tmp
, parm
, 1);
2938 rmem
= adjust_address_nv (tmp
, inner
, 0);
2939 imem
= adjust_address_nv (tmp
, inner
, GET_MODE_SIZE (inner
));
2940 push_to_sequence2 (all
->first_conversion_insn
,
2941 all
->last_conversion_insn
);
2942 emit_move_insn (rmem
, real
);
2943 emit_move_insn (imem
, imag
);
2944 all
->first_conversion_insn
= get_insns ();
2945 all
->last_conversion_insn
= get_last_insn ();
2949 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
2950 SET_DECL_RTL (parm
, tmp
);
2952 real
= DECL_INCOMING_RTL (fnargs
);
2953 imag
= DECL_INCOMING_RTL (TREE_CHAIN (fnargs
));
2954 if (inner
!= GET_MODE (real
))
2956 real
= gen_lowpart_SUBREG (inner
, real
);
2957 imag
= gen_lowpart_SUBREG (inner
, imag
);
2959 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
2960 set_decl_incoming_rtl (parm
, tmp
, false);
2961 fnargs
= TREE_CHAIN (fnargs
);
2965 SET_DECL_RTL (parm
, DECL_RTL (fnargs
));
2966 set_decl_incoming_rtl (parm
, DECL_INCOMING_RTL (fnargs
), false);
2968 /* Set MEM_EXPR to the original decl, i.e. to PARM,
2969 instead of the copy of decl, i.e. FNARGS. */
2970 if (DECL_INCOMING_RTL (parm
) && MEM_P (DECL_INCOMING_RTL (parm
)))
2971 set_mem_expr (DECL_INCOMING_RTL (parm
), parm
);
2974 fnargs
= TREE_CHAIN (fnargs
);
2978 /* Assign RTL expressions to the function's parameters. This may involve
2979 copying them into registers and using those registers as the DECL_RTL. */
2982 assign_parms (tree fndecl
)
2984 struct assign_parm_data_all all
;
2987 crtl
->args
.internal_arg_pointer
2988 = targetm
.calls
.internal_arg_pointer ();
2990 assign_parms_initialize_all (&all
);
2991 fnargs
= assign_parms_augmented_arg_list (&all
);
2993 for (parm
= fnargs
; parm
; parm
= TREE_CHAIN (parm
))
2995 struct assign_parm_data_one data
;
2997 /* Extract the type of PARM; adjust it according to ABI. */
2998 assign_parm_find_data_types (&all
, parm
, &data
);
3000 /* Early out for errors and void parameters. */
3001 if (data
.passed_mode
== VOIDmode
)
3003 SET_DECL_RTL (parm
, const0_rtx
);
3004 DECL_INCOMING_RTL (parm
) = DECL_RTL (parm
);
3008 /* Estimate stack alignment from parameter alignment. */
3009 if (SUPPORTS_STACK_ALIGNMENT
)
3011 unsigned int align
= FUNCTION_ARG_BOUNDARY (data
.promoted_mode
,
3013 if (TYPE_ALIGN (data
.nominal_type
) > align
)
3014 align
= TYPE_ALIGN (data
.passed_type
);
3015 if (crtl
->stack_alignment_estimated
< align
)
3017 gcc_assert (!crtl
->stack_realign_processed
);
3018 crtl
->stack_alignment_estimated
= align
;
3022 if (cfun
->stdarg
&& !TREE_CHAIN (parm
))
3023 assign_parms_setup_varargs (&all
, &data
, false);
3025 /* Find out where the parameter arrives in this function. */
3026 assign_parm_find_entry_rtl (&all
, &data
);
3028 /* Find out where stack space for this parameter might be. */
3029 if (assign_parm_is_stack_parm (&all
, &data
))
3031 assign_parm_find_stack_rtl (parm
, &data
);
3032 assign_parm_adjust_entry_rtl (&data
);
3035 /* Record permanently how this parm was passed. */
3036 set_decl_incoming_rtl (parm
, data
.entry_parm
, data
.passed_pointer
);
3038 /* Update info on where next arg arrives in registers. */
3039 FUNCTION_ARG_ADVANCE (all
.args_so_far
, data
.promoted_mode
,
3040 data
.passed_type
, data
.named_arg
);
3042 assign_parm_adjust_stack_rtl (&data
);
3044 if (assign_parm_setup_block_p (&data
))
3045 assign_parm_setup_block (&all
, parm
, &data
);
3046 else if (data
.passed_pointer
|| use_register_for_decl (parm
))
3047 assign_parm_setup_reg (&all
, parm
, &data
);
3049 assign_parm_setup_stack (&all
, parm
, &data
);
3052 if (targetm
.calls
.split_complex_arg
&& fnargs
!= all
.orig_fnargs
)
3053 assign_parms_unsplit_complex (&all
, fnargs
);
3055 /* Output all parameter conversion instructions (possibly including calls)
3056 now that all parameters have been copied out of hard registers. */
3057 emit_insn (all
.first_conversion_insn
);
3059 /* Estimate reload stack alignment from scalar return mode. */
3060 if (SUPPORTS_STACK_ALIGNMENT
)
3062 if (DECL_RESULT (fndecl
))
3064 tree type
= TREE_TYPE (DECL_RESULT (fndecl
));
3065 enum machine_mode mode
= TYPE_MODE (type
);
3069 && !AGGREGATE_TYPE_P (type
))
3071 unsigned int align
= GET_MODE_ALIGNMENT (mode
);
3072 if (crtl
->stack_alignment_estimated
< align
)
3074 gcc_assert (!crtl
->stack_realign_processed
);
3075 crtl
->stack_alignment_estimated
= align
;
3081 /* If we are receiving a struct value address as the first argument, set up
3082 the RTL for the function result. As this might require code to convert
3083 the transmitted address to Pmode, we do this here to ensure that possible
3084 preliminary conversions of the address have been emitted already. */
3085 if (all
.function_result_decl
)
3087 tree result
= DECL_RESULT (current_function_decl
);
3088 rtx addr
= DECL_RTL (all
.function_result_decl
);
3091 if (DECL_BY_REFERENCE (result
))
3095 addr
= convert_memory_address (Pmode
, addr
);
3096 x
= gen_rtx_MEM (DECL_MODE (result
), addr
);
3097 set_mem_attributes (x
, result
, 1);
3099 SET_DECL_RTL (result
, x
);
3102 /* We have aligned all the args, so add space for the pretend args. */
3103 crtl
->args
.pretend_args_size
= all
.pretend_args_size
;
3104 all
.stack_args_size
.constant
+= all
.extra_pretend_bytes
;
3105 crtl
->args
.size
= all
.stack_args_size
.constant
;
3107 /* Adjust function incoming argument size for alignment and
3110 #ifdef REG_PARM_STACK_SPACE
3111 crtl
->args
.size
= MAX (crtl
->args
.size
,
3112 REG_PARM_STACK_SPACE (fndecl
));
3115 crtl
->args
.size
= CEIL_ROUND (crtl
->args
.size
,
3116 PARM_BOUNDARY
/ BITS_PER_UNIT
);
3118 #ifdef ARGS_GROW_DOWNWARD
3119 crtl
->args
.arg_offset_rtx
3120 = (all
.stack_args_size
.var
== 0 ? GEN_INT (-all
.stack_args_size
.constant
)
3121 : expand_expr (size_diffop (all
.stack_args_size
.var
,
3122 size_int (-all
.stack_args_size
.constant
)),
3123 NULL_RTX
, VOIDmode
, 0));
3125 crtl
->args
.arg_offset_rtx
= ARGS_SIZE_RTX (all
.stack_args_size
);
3128 /* See how many bytes, if any, of its args a function should try to pop
3131 crtl
->args
.pops_args
= RETURN_POPS_ARGS (fndecl
, TREE_TYPE (fndecl
),
3134 /* For stdarg.h function, save info about
3135 regs and stack space used by the named args. */
3137 crtl
->args
.info
= all
.args_so_far
;
3139 /* Set the rtx used for the function return value. Put this in its
3140 own variable so any optimizers that need this information don't have
3141 to include tree.h. Do this here so it gets done when an inlined
3142 function gets output. */
3145 = (DECL_RTL_SET_P (DECL_RESULT (fndecl
))
3146 ? DECL_RTL (DECL_RESULT (fndecl
)) : NULL_RTX
);
3148 /* If scalar return value was computed in a pseudo-reg, or was a named
3149 return value that got dumped to the stack, copy that to the hard
3151 if (DECL_RTL_SET_P (DECL_RESULT (fndecl
)))
3153 tree decl_result
= DECL_RESULT (fndecl
);
3154 rtx decl_rtl
= DECL_RTL (decl_result
);
3156 if (REG_P (decl_rtl
)
3157 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
3158 : DECL_REGISTER (decl_result
))
3162 real_decl_rtl
= targetm
.calls
.function_value (TREE_TYPE (decl_result
),
3164 REG_FUNCTION_VALUE_P (real_decl_rtl
) = 1;
3165 /* The delay slot scheduler assumes that crtl->return_rtx
3166 holds the hard register containing the return value, not a
3167 temporary pseudo. */
3168 crtl
->return_rtx
= real_decl_rtl
;
3173 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3174 For all seen types, gimplify their sizes. */
3177 gimplify_parm_type (tree
*tp
, int *walk_subtrees
, void *data
)
3184 if (POINTER_TYPE_P (t
))
3186 else if (TYPE_SIZE (t
) && !TREE_CONSTANT (TYPE_SIZE (t
))
3187 && !TYPE_SIZES_GIMPLIFIED (t
))
3189 gimplify_type_sizes (t
, (gimple_seq
*) data
);
3197 /* Gimplify the parameter list for current_function_decl. This involves
3198 evaluating SAVE_EXPRs of variable sized parameters and generating code
3199 to implement callee-copies reference parameters. Returns a sequence of
3200 statements to add to the beginning of the function. */
3203 gimplify_parameters (void)
3205 struct assign_parm_data_all all
;
3207 gimple_seq stmts
= NULL
;
3209 assign_parms_initialize_all (&all
);
3210 fnargs
= assign_parms_augmented_arg_list (&all
);
3212 for (parm
= fnargs
; parm
; parm
= TREE_CHAIN (parm
))
3214 struct assign_parm_data_one data
;
3216 /* Extract the type of PARM; adjust it according to ABI. */
3217 assign_parm_find_data_types (&all
, parm
, &data
);
3219 /* Early out for errors and void parameters. */
3220 if (data
.passed_mode
== VOIDmode
|| DECL_SIZE (parm
) == NULL
)
3223 /* Update info on where next arg arrives in registers. */
3224 FUNCTION_ARG_ADVANCE (all
.args_so_far
, data
.promoted_mode
,
3225 data
.passed_type
, data
.named_arg
);
3227 /* ??? Once upon a time variable_size stuffed parameter list
3228 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3229 turned out to be less than manageable in the gimple world.
3230 Now we have to hunt them down ourselves. */
3231 walk_tree_without_duplicates (&data
.passed_type
,
3232 gimplify_parm_type
, &stmts
);
3234 if (TREE_CODE (DECL_SIZE_UNIT (parm
)) != INTEGER_CST
)
3236 gimplify_one_sizepos (&DECL_SIZE (parm
), &stmts
);
3237 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm
), &stmts
);
3240 if (data
.passed_pointer
)
3242 tree type
= TREE_TYPE (data
.passed_type
);
3243 if (reference_callee_copied (&all
.args_so_far
, TYPE_MODE (type
),
3244 type
, data
.named_arg
))
3248 /* For constant-sized objects, this is trivial; for
3249 variable-sized objects, we have to play games. */
3250 if (TREE_CODE (DECL_SIZE_UNIT (parm
)) == INTEGER_CST
3251 && !(flag_stack_check
== GENERIC_STACK_CHECK
3252 && compare_tree_int (DECL_SIZE_UNIT (parm
),
3253 STACK_CHECK_MAX_VAR_SIZE
) > 0))
3255 local
= create_tmp_var (type
, get_name (parm
));
3256 DECL_IGNORED_P (local
) = 0;
3260 tree ptr_type
, addr
;
3262 ptr_type
= build_pointer_type (type
);
3263 addr
= create_tmp_var (ptr_type
, get_name (parm
));
3264 DECL_IGNORED_P (addr
) = 0;
3265 local
= build_fold_indirect_ref (addr
);
3267 t
= built_in_decls
[BUILT_IN_ALLOCA
];
3268 t
= build_call_expr (t
, 1, DECL_SIZE_UNIT (parm
));
3269 t
= fold_convert (ptr_type
, t
);
3270 t
= build2 (MODIFY_EXPR
, TREE_TYPE (addr
), addr
, t
);
3271 gimplify_and_add (t
, &stmts
);
3274 gimplify_assign (local
, parm
, &stmts
);
3276 SET_DECL_VALUE_EXPR (parm
, local
);
3277 DECL_HAS_VALUE_EXPR_P (parm
) = 1;
3285 /* Compute the size and offset from the start of the stacked arguments for a
3286 parm passed in mode PASSED_MODE and with type TYPE.
3288 INITIAL_OFFSET_PTR points to the current offset into the stacked
3291 The starting offset and size for this parm are returned in
3292 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3293 nonzero, the offset is that of stack slot, which is returned in
3294 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3295 padding required from the initial offset ptr to the stack slot.
3297 IN_REGS is nonzero if the argument will be passed in registers. It will
3298 never be set if REG_PARM_STACK_SPACE is not defined.
3300 FNDECL is the function in which the argument was defined.
3302 There are two types of rounding that are done. The first, controlled by
3303 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
3304 list to be aligned to the specific boundary (in bits). This rounding
3305 affects the initial and starting offsets, but not the argument size.
3307 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3308 optionally rounds the size of the parm to PARM_BOUNDARY. The
3309 initial offset is not affected by this rounding, while the size always
3310 is and the starting offset may be. */
3312 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3313 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3314 callers pass in the total size of args so far as
3315 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
3318 locate_and_pad_parm (enum machine_mode passed_mode
, tree type
, int in_regs
,
3319 int partial
, tree fndecl ATTRIBUTE_UNUSED
,
3320 struct args_size
*initial_offset_ptr
,
3321 struct locate_and_pad_arg_data
*locate
)
3324 enum direction where_pad
;
3325 unsigned int boundary
;
3326 int reg_parm_stack_space
= 0;
3327 int part_size_in_regs
;
3329 #ifdef REG_PARM_STACK_SPACE
3330 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
3332 /* If we have found a stack parm before we reach the end of the
3333 area reserved for registers, skip that area. */
3336 if (reg_parm_stack_space
> 0)
3338 if (initial_offset_ptr
->var
)
3340 initial_offset_ptr
->var
3341 = size_binop (MAX_EXPR
, ARGS_SIZE_TREE (*initial_offset_ptr
),
3342 ssize_int (reg_parm_stack_space
));
3343 initial_offset_ptr
->constant
= 0;
3345 else if (initial_offset_ptr
->constant
< reg_parm_stack_space
)
3346 initial_offset_ptr
->constant
= reg_parm_stack_space
;
3349 #endif /* REG_PARM_STACK_SPACE */
3351 part_size_in_regs
= (reg_parm_stack_space
== 0 ? partial
: 0);
3354 = type
? size_in_bytes (type
) : size_int (GET_MODE_SIZE (passed_mode
));
3355 where_pad
= FUNCTION_ARG_PADDING (passed_mode
, type
);
3356 boundary
= FUNCTION_ARG_BOUNDARY (passed_mode
, type
);
3357 locate
->where_pad
= where_pad
;
3359 /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT. */
3360 if (boundary
> MAX_SUPPORTED_STACK_ALIGNMENT
)
3361 boundary
= MAX_SUPPORTED_STACK_ALIGNMENT
;
3363 locate
->boundary
= boundary
;
3365 if (SUPPORTS_STACK_ALIGNMENT
)
3367 /* stack_alignment_estimated can't change after stack has been
3369 if (crtl
->stack_alignment_estimated
< boundary
)
3371 if (!crtl
->stack_realign_processed
)
3372 crtl
->stack_alignment_estimated
= boundary
;
3375 /* If stack is realigned and stack alignment value
3376 hasn't been finalized, it is OK not to increase
3377 stack_alignment_estimated. The bigger alignment
3378 requirement is recorded in stack_alignment_needed
3380 gcc_assert (!crtl
->stack_realign_finalized
3381 && crtl
->stack_realign_needed
);
3386 /* Remember if the outgoing parameter requires extra alignment on the
3387 calling function side. */
3388 if (crtl
->stack_alignment_needed
< boundary
)
3389 crtl
->stack_alignment_needed
= boundary
;
3390 if (crtl
->max_used_stack_slot_alignment
< crtl
->stack_alignment_needed
)
3391 crtl
->max_used_stack_slot_alignment
= crtl
->stack_alignment_needed
;
3392 if (crtl
->preferred_stack_boundary
< boundary
)
3393 crtl
->preferred_stack_boundary
= boundary
;
3395 #ifdef ARGS_GROW_DOWNWARD
3396 locate
->slot_offset
.constant
= -initial_offset_ptr
->constant
;
3397 if (initial_offset_ptr
->var
)
3398 locate
->slot_offset
.var
= size_binop (MINUS_EXPR
, ssize_int (0),
3399 initial_offset_ptr
->var
);
3403 if (where_pad
!= none
3404 && (!host_integerp (sizetree
, 1)
3405 || (tree_low_cst (sizetree
, 1) * BITS_PER_UNIT
) % PARM_BOUNDARY
))
3406 s2
= round_up (s2
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3407 SUB_PARM_SIZE (locate
->slot_offset
, s2
);
3410 locate
->slot_offset
.constant
+= part_size_in_regs
;
3413 #ifdef REG_PARM_STACK_SPACE
3414 || REG_PARM_STACK_SPACE (fndecl
) > 0
3417 pad_to_arg_alignment (&locate
->slot_offset
, boundary
,
3418 &locate
->alignment_pad
);
3420 locate
->size
.constant
= (-initial_offset_ptr
->constant
3421 - locate
->slot_offset
.constant
);
3422 if (initial_offset_ptr
->var
)
3423 locate
->size
.var
= size_binop (MINUS_EXPR
,
3424 size_binop (MINUS_EXPR
,
3426 initial_offset_ptr
->var
),
3427 locate
->slot_offset
.var
);
3429 /* Pad_below needs the pre-rounded size to know how much to pad
3431 locate
->offset
= locate
->slot_offset
;
3432 if (where_pad
== downward
)
3433 pad_below (&locate
->offset
, passed_mode
, sizetree
);
3435 #else /* !ARGS_GROW_DOWNWARD */
3437 #ifdef REG_PARM_STACK_SPACE
3438 || REG_PARM_STACK_SPACE (fndecl
) > 0
3441 pad_to_arg_alignment (initial_offset_ptr
, boundary
,
3442 &locate
->alignment_pad
);
3443 locate
->slot_offset
= *initial_offset_ptr
;
3445 #ifdef PUSH_ROUNDING
3446 if (passed_mode
!= BLKmode
)
3447 sizetree
= size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree
)));
3450 /* Pad_below needs the pre-rounded size to know how much to pad below
3451 so this must be done before rounding up. */
3452 locate
->offset
= locate
->slot_offset
;
3453 if (where_pad
== downward
)
3454 pad_below (&locate
->offset
, passed_mode
, sizetree
);
3456 if (where_pad
!= none
3457 && (!host_integerp (sizetree
, 1)
3458 || (tree_low_cst (sizetree
, 1) * BITS_PER_UNIT
) % PARM_BOUNDARY
))
3459 sizetree
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3461 ADD_PARM_SIZE (locate
->size
, sizetree
);
3463 locate
->size
.constant
-= part_size_in_regs
;
3464 #endif /* ARGS_GROW_DOWNWARD */
3467 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
3468 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
3471 pad_to_arg_alignment (struct args_size
*offset_ptr
, int boundary
,
3472 struct args_size
*alignment_pad
)
3474 tree save_var
= NULL_TREE
;
3475 HOST_WIDE_INT save_constant
= 0;
3476 int boundary_in_bytes
= boundary
/ BITS_PER_UNIT
;
3477 HOST_WIDE_INT sp_offset
= STACK_POINTER_OFFSET
;
3479 #ifdef SPARC_STACK_BOUNDARY_HACK
3480 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
3481 the real alignment of %sp. However, when it does this, the
3482 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
3483 if (SPARC_STACK_BOUNDARY_HACK
)
3487 if (boundary
> PARM_BOUNDARY
)
3489 save_var
= offset_ptr
->var
;
3490 save_constant
= offset_ptr
->constant
;
3493 alignment_pad
->var
= NULL_TREE
;
3494 alignment_pad
->constant
= 0;
3496 if (boundary
> BITS_PER_UNIT
)
3498 if (offset_ptr
->var
)
3500 tree sp_offset_tree
= ssize_int (sp_offset
);
3501 tree offset
= size_binop (PLUS_EXPR
,
3502 ARGS_SIZE_TREE (*offset_ptr
),
3504 #ifdef ARGS_GROW_DOWNWARD
3505 tree rounded
= round_down (offset
, boundary
/ BITS_PER_UNIT
);
3507 tree rounded
= round_up (offset
, boundary
/ BITS_PER_UNIT
);
3510 offset_ptr
->var
= size_binop (MINUS_EXPR
, rounded
, sp_offset_tree
);
3511 /* ARGS_SIZE_TREE includes constant term. */
3512 offset_ptr
->constant
= 0;
3513 if (boundary
> PARM_BOUNDARY
)
3514 alignment_pad
->var
= size_binop (MINUS_EXPR
, offset_ptr
->var
,
3519 offset_ptr
->constant
= -sp_offset
+
3520 #ifdef ARGS_GROW_DOWNWARD
3521 FLOOR_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
3523 CEIL_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
3525 if (boundary
> PARM_BOUNDARY
)
3526 alignment_pad
->constant
= offset_ptr
->constant
- save_constant
;
3532 pad_below (struct args_size
*offset_ptr
, enum machine_mode passed_mode
, tree sizetree
)
3534 if (passed_mode
!= BLKmode
)
3536 if (GET_MODE_BITSIZE (passed_mode
) % PARM_BOUNDARY
)
3537 offset_ptr
->constant
3538 += (((GET_MODE_BITSIZE (passed_mode
) + PARM_BOUNDARY
- 1)
3539 / PARM_BOUNDARY
* PARM_BOUNDARY
/ BITS_PER_UNIT
)
3540 - GET_MODE_SIZE (passed_mode
));
3544 if (TREE_CODE (sizetree
) != INTEGER_CST
3545 || (TREE_INT_CST_LOW (sizetree
) * BITS_PER_UNIT
) % PARM_BOUNDARY
)
3547 /* Round the size up to multiple of PARM_BOUNDARY bits. */
3548 tree s2
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3550 ADD_PARM_SIZE (*offset_ptr
, s2
);
3551 SUB_PARM_SIZE (*offset_ptr
, sizetree
);
3557 /* True if register REGNO was alive at a place where `setjmp' was
3558 called and was set more than once or is an argument. Such regs may
3559 be clobbered by `longjmp'. */
3562 regno_clobbered_at_setjmp (bitmap setjmp_crosses
, int regno
)
3564 /* There appear to be cases where some local vars never reach the
3565 backend but have bogus regnos. */
3566 if (regno
>= max_reg_num ())
3569 return ((REG_N_SETS (regno
) > 1
3570 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR
), regno
))
3571 && REGNO_REG_SET_P (setjmp_crosses
, regno
));
3574 /* Walk the tree of blocks describing the binding levels within a
3575 function and warn about variables the might be killed by setjmp or
3576 vfork. This is done after calling flow_analysis before register
3577 allocation since that will clobber the pseudo-regs to hard
3581 setjmp_vars_warning (bitmap setjmp_crosses
, tree block
)
3585 for (decl
= BLOCK_VARS (block
); decl
; decl
= TREE_CHAIN (decl
))
3587 if (TREE_CODE (decl
) == VAR_DECL
3588 && DECL_RTL_SET_P (decl
)
3589 && REG_P (DECL_RTL (decl
))
3590 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
3591 warning (OPT_Wclobbered
, "variable %q+D might be clobbered by"
3592 " %<longjmp%> or %<vfork%>", decl
);
3595 for (sub
= BLOCK_SUBBLOCKS (block
); sub
; sub
= BLOCK_CHAIN (sub
))
3596 setjmp_vars_warning (setjmp_crosses
, sub
);
3599 /* Do the appropriate part of setjmp_vars_warning
3600 but for arguments instead of local variables. */
3603 setjmp_args_warning (bitmap setjmp_crosses
)
3606 for (decl
= DECL_ARGUMENTS (current_function_decl
);
3607 decl
; decl
= TREE_CHAIN (decl
))
3608 if (DECL_RTL (decl
) != 0
3609 && REG_P (DECL_RTL (decl
))
3610 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
3611 warning (OPT_Wclobbered
,
3612 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
3616 /* Generate warning messages for variables live across setjmp. */
3619 generate_setjmp_warnings (void)
3621 bitmap setjmp_crosses
= regstat_get_setjmp_crosses ();
3623 if (n_basic_blocks
== NUM_FIXED_BLOCKS
3624 || bitmap_empty_p (setjmp_crosses
))
3627 setjmp_vars_warning (setjmp_crosses
, DECL_INITIAL (current_function_decl
));
3628 setjmp_args_warning (setjmp_crosses
);
3632 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
3633 and create duplicate blocks. */
3634 /* ??? Need an option to either create block fragments or to create
3635 abstract origin duplicates of a source block. It really depends
3636 on what optimization has been performed. */
3639 reorder_blocks (void)
3641 tree block
= DECL_INITIAL (current_function_decl
);
3642 VEC(tree
,heap
) *block_stack
;
3644 if (block
== NULL_TREE
)
3647 block_stack
= VEC_alloc (tree
, heap
, 10);
3649 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
3650 clear_block_marks (block
);
3652 /* Prune the old trees away, so that they don't get in the way. */
3653 BLOCK_SUBBLOCKS (block
) = NULL_TREE
;
3654 BLOCK_CHAIN (block
) = NULL_TREE
;
3656 /* Recreate the block tree from the note nesting. */
3657 reorder_blocks_1 (get_insns (), block
, &block_stack
);
3658 BLOCK_SUBBLOCKS (block
) = blocks_nreverse (BLOCK_SUBBLOCKS (block
));
3660 VEC_free (tree
, heap
, block_stack
);
3663 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
3666 clear_block_marks (tree block
)
3670 TREE_ASM_WRITTEN (block
) = 0;
3671 clear_block_marks (BLOCK_SUBBLOCKS (block
));
3672 block
= BLOCK_CHAIN (block
);
3677 reorder_blocks_1 (rtx insns
, tree current_block
, VEC(tree
,heap
) **p_block_stack
)
3681 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
3685 if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_BEG
)
3687 tree block
= NOTE_BLOCK (insn
);
3690 origin
= (BLOCK_FRAGMENT_ORIGIN (block
)
3691 ? BLOCK_FRAGMENT_ORIGIN (block
)
3694 /* If we have seen this block before, that means it now
3695 spans multiple address regions. Create a new fragment. */
3696 if (TREE_ASM_WRITTEN (block
))
3698 tree new_block
= copy_node (block
);
3700 BLOCK_FRAGMENT_ORIGIN (new_block
) = origin
;
3701 BLOCK_FRAGMENT_CHAIN (new_block
)
3702 = BLOCK_FRAGMENT_CHAIN (origin
);
3703 BLOCK_FRAGMENT_CHAIN (origin
) = new_block
;
3705 NOTE_BLOCK (insn
) = new_block
;
3709 BLOCK_SUBBLOCKS (block
) = 0;
3710 TREE_ASM_WRITTEN (block
) = 1;
3711 /* When there's only one block for the entire function,
3712 current_block == block and we mustn't do this, it
3713 will cause infinite recursion. */
3714 if (block
!= current_block
)
3716 if (block
!= origin
)
3717 gcc_assert (BLOCK_SUPERCONTEXT (origin
) == current_block
);
3719 BLOCK_SUPERCONTEXT (block
) = current_block
;
3720 BLOCK_CHAIN (block
) = BLOCK_SUBBLOCKS (current_block
);
3721 BLOCK_SUBBLOCKS (current_block
) = block
;
3722 current_block
= origin
;
3724 VEC_safe_push (tree
, heap
, *p_block_stack
, block
);
3726 else if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_END
)
3728 NOTE_BLOCK (insn
) = VEC_pop (tree
, *p_block_stack
);
3729 BLOCK_SUBBLOCKS (current_block
)
3730 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block
));
3731 current_block
= BLOCK_SUPERCONTEXT (current_block
);
3737 /* Reverse the order of elements in the chain T of blocks,
3738 and return the new head of the chain (old last element). */
3741 blocks_nreverse (tree t
)
3743 tree prev
= 0, decl
, next
;
3744 for (decl
= t
; decl
; decl
= next
)
3746 next
= BLOCK_CHAIN (decl
);
3747 BLOCK_CHAIN (decl
) = prev
;
3753 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
3754 non-NULL, list them all into VECTOR, in a depth-first preorder
3755 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
3759 all_blocks (tree block
, tree
*vector
)
3765 TREE_ASM_WRITTEN (block
) = 0;
3767 /* Record this block. */
3769 vector
[n_blocks
] = block
;
3773 /* Record the subblocks, and their subblocks... */
3774 n_blocks
+= all_blocks (BLOCK_SUBBLOCKS (block
),
3775 vector
? vector
+ n_blocks
: 0);
3776 block
= BLOCK_CHAIN (block
);
3782 /* Return a vector containing all the blocks rooted at BLOCK. The
3783 number of elements in the vector is stored in N_BLOCKS_P. The
3784 vector is dynamically allocated; it is the caller's responsibility
3785 to call `free' on the pointer returned. */
3788 get_block_vector (tree block
, int *n_blocks_p
)
3792 *n_blocks_p
= all_blocks (block
, NULL
);
3793 block_vector
= XNEWVEC (tree
, *n_blocks_p
);
3794 all_blocks (block
, block_vector
);
3796 return block_vector
;
3799 static GTY(()) int next_block_index
= 2;
3801 /* Set BLOCK_NUMBER for all the blocks in FN. */
3804 number_blocks (tree fn
)
3810 /* For SDB and XCOFF debugging output, we start numbering the blocks
3811 from 1 within each function, rather than keeping a running
3813 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
3814 if (write_symbols
== SDB_DEBUG
|| write_symbols
== XCOFF_DEBUG
)
3815 next_block_index
= 1;
3818 block_vector
= get_block_vector (DECL_INITIAL (fn
), &n_blocks
);
3820 /* The top-level BLOCK isn't numbered at all. */
3821 for (i
= 1; i
< n_blocks
; ++i
)
3822 /* We number the blocks from two. */
3823 BLOCK_NUMBER (block_vector
[i
]) = next_block_index
++;
3825 free (block_vector
);
3830 /* If VAR is present in a subblock of BLOCK, return the subblock. */
3833 debug_find_var_in_block_tree (tree var
, tree block
)
3837 for (t
= BLOCK_VARS (block
); t
; t
= TREE_CHAIN (t
))
3841 for (t
= BLOCK_SUBBLOCKS (block
); t
; t
= TREE_CHAIN (t
))
3843 tree ret
= debug_find_var_in_block_tree (var
, t
);
3851 /* Keep track of whether we're in a dummy function context. If we are,
3852 we don't want to invoke the set_current_function hook, because we'll
3853 get into trouble if the hook calls target_reinit () recursively or
3854 when the initial initialization is not yet complete. */
3856 static bool in_dummy_function
;
3858 /* Invoke the target hook when setting cfun. Update the optimization options
3859 if the function uses different options than the default. */
3862 invoke_set_current_function_hook (tree fndecl
)
3864 if (!in_dummy_function
)
3866 tree opts
= ((fndecl
)
3867 ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl
)
3868 : optimization_default_node
);
3871 opts
= optimization_default_node
;
3873 /* Change optimization options if needed. */
3874 if (optimization_current_node
!= opts
)
3876 optimization_current_node
= opts
;
3877 cl_optimization_restore (TREE_OPTIMIZATION (opts
));
3880 targetm
.set_current_function (fndecl
);
3884 /* cfun should never be set directly; use this function. */
3887 set_cfun (struct function
*new_cfun
)
3889 if (cfun
!= new_cfun
)
3892 invoke_set_current_function_hook (new_cfun
? new_cfun
->decl
: NULL_TREE
);
3896 /* Initialized with NOGC, making this poisonous to the garbage collector. */
3898 static VEC(function_p
,heap
) *cfun_stack
;
3900 /* Push the current cfun onto the stack, and set cfun to new_cfun. */
3903 push_cfun (struct function
*new_cfun
)
3905 VEC_safe_push (function_p
, heap
, cfun_stack
, cfun
);
3906 set_cfun (new_cfun
);
3909 /* Pop cfun from the stack. */
3914 struct function
*new_cfun
= VEC_pop (function_p
, cfun_stack
);
3915 set_cfun (new_cfun
);
3918 /* Return value of funcdef and increase it. */
3920 get_next_funcdef_no (void)
3922 return funcdef_no
++;
3925 /* Allocate a function structure for FNDECL and set its contents
3926 to the defaults. Set cfun to the newly-allocated object.
3927 Some of the helper functions invoked during initialization assume
3928 that cfun has already been set. Therefore, assign the new object
3929 directly into cfun and invoke the back end hook explicitly at the
3930 very end, rather than initializing a temporary and calling set_cfun
3933 ABSTRACT_P is true if this is a function that will never be seen by
3934 the middle-end. Such functions are front-end concepts (like C++
3935 function templates) that do not correspond directly to functions
3936 placed in object files. */
3939 allocate_struct_function (tree fndecl
, bool abstract_p
)
3942 tree fntype
= fndecl
? TREE_TYPE (fndecl
) : NULL_TREE
;
3944 cfun
= GGC_CNEW (struct function
);
3946 cfun
->function_frequency
= FUNCTION_FREQUENCY_NORMAL
;
3948 init_eh_for_function ();
3950 if (init_machine_status
)
3951 cfun
->machine
= (*init_machine_status
) ();
3953 #ifdef OVERRIDE_ABI_FORMAT
3954 OVERRIDE_ABI_FORMAT (fndecl
);
3957 if (fndecl
!= NULL_TREE
)
3959 DECL_STRUCT_FUNCTION (fndecl
) = cfun
;
3960 cfun
->decl
= fndecl
;
3961 current_function_funcdef_no
= get_next_funcdef_no ();
3963 result
= DECL_RESULT (fndecl
);
3964 if (!abstract_p
&& aggregate_value_p (result
, fndecl
))
3966 #ifdef PCC_STATIC_STRUCT_RETURN
3967 cfun
->returns_pcc_struct
= 1;
3969 cfun
->returns_struct
= 1;
3974 && TYPE_ARG_TYPES (fntype
) != 0
3975 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype
)))
3976 != void_type_node
));
3978 /* Assume all registers in stdarg functions need to be saved. */
3979 cfun
->va_list_gpr_size
= VA_LIST_MAX_GPR_SIZE
;
3980 cfun
->va_list_fpr_size
= VA_LIST_MAX_FPR_SIZE
;
3983 invoke_set_current_function_hook (fndecl
);
3986 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
3987 instead of just setting it. */
3990 push_struct_function (tree fndecl
)
3992 VEC_safe_push (function_p
, heap
, cfun_stack
, cfun
);
3993 allocate_struct_function (fndecl
, false);
3996 /* Reset cfun, and other non-struct-function variables to defaults as
3997 appropriate for emitting rtl at the start of a function. */
4000 prepare_function_start (void)
4002 gcc_assert (!crtl
->emit
.x_last_insn
);
4004 init_varasm_status ();
4006 default_rtl_profile ();
4008 cse_not_expected
= ! optimize
;
4010 /* Caller save not needed yet. */
4011 caller_save_needed
= 0;
4013 /* We haven't done register allocation yet. */
4016 /* Indicate that we have not instantiated virtual registers yet. */
4017 virtuals_instantiated
= 0;
4019 /* Indicate that we want CONCATs now. */
4020 generating_concat_p
= 1;
4022 /* Indicate we have no need of a frame pointer yet. */
4023 frame_pointer_needed
= 0;
4026 /* Initialize the rtl expansion mechanism so that we can do simple things
4027 like generate sequences. This is used to provide a context during global
4028 initialization of some passes. You must call expand_dummy_function_end
4029 to exit this context. */
4032 init_dummy_function_start (void)
4034 gcc_assert (!in_dummy_function
);
4035 in_dummy_function
= true;
4036 push_struct_function (NULL_TREE
);
4037 prepare_function_start ();
4040 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
4041 and initialize static variables for generating RTL for the statements
4045 init_function_start (tree subr
)
4047 if (subr
&& DECL_STRUCT_FUNCTION (subr
))
4048 set_cfun (DECL_STRUCT_FUNCTION (subr
));
4050 allocate_struct_function (subr
, false);
4051 prepare_function_start ();
4053 /* Warn if this value is an aggregate type,
4054 regardless of which calling convention we are using for it. */
4055 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr
))))
4056 warning (OPT_Waggregate_return
, "function returns an aggregate");
4059 /* Make sure all values used by the optimization passes have sane
4062 init_function_for_compilation (void)
4066 /* No prologue/epilogue insns yet. Make sure that these vectors are
4068 gcc_assert (VEC_length (int, prologue
) == 0);
4069 gcc_assert (VEC_length (int, epilogue
) == 0);
4070 gcc_assert (VEC_length (int, sibcall_epilogue
) == 0);
4074 struct rtl_opt_pass pass_init_function
=
4080 init_function_for_compilation
, /* execute */
4083 0, /* static_pass_number */
4085 0, /* properties_required */
4086 0, /* properties_provided */
4087 0, /* properties_destroyed */
4088 0, /* todo_flags_start */
4089 0 /* todo_flags_finish */
4095 expand_main_function (void)
4097 #if (defined(INVOKE__main) \
4098 || (!defined(HAS_INIT_SECTION) \
4099 && !defined(INIT_SECTION_ASM_OP) \
4100 && !defined(INIT_ARRAY_SECTION_ASM_OP)))
4101 emit_library_call (init_one_libfunc (NAME__MAIN
), LCT_NORMAL
, VOIDmode
, 0);
4105 /* Expand code to initialize the stack_protect_guard. This is invoked at
4106 the beginning of a function to be protected. */
4108 #ifndef HAVE_stack_protect_set
4109 # define HAVE_stack_protect_set 0
4110 # define gen_stack_protect_set(x,y) (gcc_unreachable (), NULL_RTX)
4114 stack_protect_prologue (void)
4116 tree guard_decl
= targetm
.stack_protect_guard ();
4119 /* Avoid expand_expr here, because we don't want guard_decl pulled
4120 into registers unless absolutely necessary. And we know that
4121 crtl->stack_protect_guard is a local stack slot, so this skips
4123 x
= validize_mem (DECL_RTL (crtl
->stack_protect_guard
));
4124 y
= validize_mem (DECL_RTL (guard_decl
));
4126 /* Allow the target to copy from Y to X without leaking Y into a
4128 if (HAVE_stack_protect_set
)
4130 rtx insn
= gen_stack_protect_set (x
, y
);
4138 /* Otherwise do a straight move. */
4139 emit_move_insn (x
, y
);
4142 /* Expand code to verify the stack_protect_guard. This is invoked at
4143 the end of a function to be protected. */
4145 #ifndef HAVE_stack_protect_test
4146 # define HAVE_stack_protect_test 0
4147 # define gen_stack_protect_test(x, y, z) (gcc_unreachable (), NULL_RTX)
4151 stack_protect_epilogue (void)
4153 tree guard_decl
= targetm
.stack_protect_guard ();
4154 rtx label
= gen_label_rtx ();
4157 /* Avoid expand_expr here, because we don't want guard_decl pulled
4158 into registers unless absolutely necessary. And we know that
4159 crtl->stack_protect_guard is a local stack slot, so this skips
4161 x
= validize_mem (DECL_RTL (crtl
->stack_protect_guard
));
4162 y
= validize_mem (DECL_RTL (guard_decl
));
4164 /* Allow the target to compare Y with X without leaking either into
4166 switch (HAVE_stack_protect_test
!= 0)
4169 tmp
= gen_stack_protect_test (x
, y
, label
);
4178 emit_cmp_and_jump_insns (x
, y
, EQ
, NULL_RTX
, ptr_mode
, 1, label
);
4182 /* The noreturn predictor has been moved to the tree level. The rtl-level
4183 predictors estimate this branch about 20%, which isn't enough to get
4184 things moved out of line. Since this is the only extant case of adding
4185 a noreturn function at the rtl level, it doesn't seem worth doing ought
4186 except adding the prediction by hand. */
4187 tmp
= get_last_insn ();
4189 predict_insn_def (tmp
, PRED_NORETURN
, TAKEN
);
4191 expand_expr_stmt (targetm
.stack_protect_fail ());
4195 /* Start the RTL for a new function, and set variables used for
4197 SUBR is the FUNCTION_DECL node.
4198 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4199 the function's parameters, which must be run at any return statement. */
4202 expand_function_start (tree subr
)
4204 /* Make sure volatile mem refs aren't considered
4205 valid operands of arithmetic insns. */
4206 init_recog_no_volatile ();
4210 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr
));
4213 = (stack_limit_rtx
!= NULL_RTX
&& ! DECL_NO_LIMIT_STACK (subr
));
4215 /* Make the label for return statements to jump to. Do not special
4216 case machines with special return instructions -- they will be
4217 handled later during jump, ifcvt, or epilogue creation. */
4218 return_label
= gen_label_rtx ();
4220 /* Initialize rtx used to return the value. */
4221 /* Do this before assign_parms so that we copy the struct value address
4222 before any library calls that assign parms might generate. */
4224 /* Decide whether to return the value in memory or in a register. */
4225 if (aggregate_value_p (DECL_RESULT (subr
), subr
))
4227 /* Returning something that won't go in a register. */
4228 rtx value_address
= 0;
4230 #ifdef PCC_STATIC_STRUCT_RETURN
4231 if (cfun
->returns_pcc_struct
)
4233 int size
= int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr
)));
4234 value_address
= assemble_static_space (size
);
4239 rtx sv
= targetm
.calls
.struct_value_rtx (TREE_TYPE (subr
), 2);
4240 /* Expect to be passed the address of a place to store the value.
4241 If it is passed as an argument, assign_parms will take care of
4245 value_address
= gen_reg_rtx (Pmode
);
4246 emit_move_insn (value_address
, sv
);
4251 rtx x
= value_address
;
4252 if (!DECL_BY_REFERENCE (DECL_RESULT (subr
)))
4254 x
= gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr
)), x
);
4255 set_mem_attributes (x
, DECL_RESULT (subr
), 1);
4257 SET_DECL_RTL (DECL_RESULT (subr
), x
);
4260 else if (DECL_MODE (DECL_RESULT (subr
)) == VOIDmode
)
4261 /* If return mode is void, this decl rtl should not be used. */
4262 SET_DECL_RTL (DECL_RESULT (subr
), NULL_RTX
);
4265 /* Compute the return values into a pseudo reg, which we will copy
4266 into the true return register after the cleanups are done. */
4267 tree return_type
= TREE_TYPE (DECL_RESULT (subr
));
4268 if (TYPE_MODE (return_type
) != BLKmode
4269 && targetm
.calls
.return_in_msb (return_type
))
4270 /* expand_function_end will insert the appropriate padding in
4271 this case. Use the return value's natural (unpadded) mode
4272 within the function proper. */
4273 SET_DECL_RTL (DECL_RESULT (subr
),
4274 gen_reg_rtx (TYPE_MODE (return_type
)));
4277 /* In order to figure out what mode to use for the pseudo, we
4278 figure out what the mode of the eventual return register will
4279 actually be, and use that. */
4280 rtx hard_reg
= hard_function_value (return_type
, subr
, 0, 1);
4282 /* Structures that are returned in registers are not
4283 aggregate_value_p, so we may see a PARALLEL or a REG. */
4284 if (REG_P (hard_reg
))
4285 SET_DECL_RTL (DECL_RESULT (subr
),
4286 gen_reg_rtx (GET_MODE (hard_reg
)));
4289 gcc_assert (GET_CODE (hard_reg
) == PARALLEL
);
4290 SET_DECL_RTL (DECL_RESULT (subr
), gen_group_rtx (hard_reg
));
4294 /* Set DECL_REGISTER flag so that expand_function_end will copy the
4295 result to the real return register(s). */
4296 DECL_REGISTER (DECL_RESULT (subr
)) = 1;
4299 /* Initialize rtx for parameters and local variables.
4300 In some cases this requires emitting insns. */
4301 assign_parms (subr
);
4303 /* If function gets a static chain arg, store it. */
4304 if (cfun
->static_chain_decl
)
4306 tree parm
= cfun
->static_chain_decl
;
4307 rtx local
= gen_reg_rtx (Pmode
);
4309 set_decl_incoming_rtl (parm
, static_chain_incoming_rtx
, false);
4310 SET_DECL_RTL (parm
, local
);
4311 mark_reg_pointer (local
, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
4313 emit_move_insn (local
, static_chain_incoming_rtx
);
4316 /* If the function receives a non-local goto, then store the
4317 bits we need to restore the frame pointer. */
4318 if (cfun
->nonlocal_goto_save_area
)
4323 /* ??? We need to do this save early. Unfortunately here is
4324 before the frame variable gets declared. Help out... */
4325 tree var
= TREE_OPERAND (cfun
->nonlocal_goto_save_area
, 0);
4326 if (!DECL_RTL_SET_P (var
))
4329 t_save
= build4 (ARRAY_REF
, ptr_type_node
,
4330 cfun
->nonlocal_goto_save_area
,
4331 integer_zero_node
, NULL_TREE
, NULL_TREE
);
4332 r_save
= expand_expr (t_save
, NULL_RTX
, VOIDmode
, EXPAND_WRITE
);
4333 r_save
= convert_memory_address (Pmode
, r_save
);
4335 emit_move_insn (r_save
, targetm
.builtin_setjmp_frame_value ());
4336 update_nonlocal_goto_save_area ();
4339 /* The following was moved from init_function_start.
4340 The move is supposed to make sdb output more accurate. */
4341 /* Indicate the beginning of the function body,
4342 as opposed to parm setup. */
4343 emit_note (NOTE_INSN_FUNCTION_BEG
);
4345 gcc_assert (NOTE_P (get_last_insn ()));
4347 parm_birth_insn
= get_last_insn ();
4352 PROFILE_HOOK (current_function_funcdef_no
);
4356 /* After the display initializations is where the stack checking
4358 if(flag_stack_check
)
4359 stack_check_probe_note
= emit_note (NOTE_INSN_DELETED
);
4361 /* Make sure there is a line number after the function entry setup code. */
4362 force_next_line_note ();
4365 /* Undo the effects of init_dummy_function_start. */
4367 expand_dummy_function_end (void)
4369 gcc_assert (in_dummy_function
);
4371 /* End any sequences that failed to be closed due to syntax errors. */
4372 while (in_sequence_p ())
4375 /* Outside function body, can't compute type's actual size
4376 until next function's body starts. */
4378 free_after_parsing (cfun
);
4379 free_after_compilation (cfun
);
4381 in_dummy_function
= false;
4384 /* Call DOIT for each hard register used as a return value from
4385 the current function. */
4388 diddle_return_value (void (*doit
) (rtx
, void *), void *arg
)
4390 rtx outgoing
= crtl
->return_rtx
;
4395 if (REG_P (outgoing
))
4396 (*doit
) (outgoing
, arg
);
4397 else if (GET_CODE (outgoing
) == PARALLEL
)
4401 for (i
= 0; i
< XVECLEN (outgoing
, 0); i
++)
4403 rtx x
= XEXP (XVECEXP (outgoing
, 0, i
), 0);
4405 if (REG_P (x
) && REGNO (x
) < FIRST_PSEUDO_REGISTER
)
4412 do_clobber_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
4418 clobber_return_register (void)
4420 diddle_return_value (do_clobber_return_reg
, NULL
);
4422 /* In case we do use pseudo to return value, clobber it too. */
4423 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
4425 tree decl_result
= DECL_RESULT (current_function_decl
);
4426 rtx decl_rtl
= DECL_RTL (decl_result
);
4427 if (REG_P (decl_rtl
) && REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
)
4429 do_clobber_return_reg (decl_rtl
, NULL
);
4435 do_use_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
4441 use_return_register (void)
4443 diddle_return_value (do_use_return_reg
, NULL
);
4446 /* Possibly warn about unused parameters. */
4448 do_warn_unused_parameter (tree fn
)
4452 for (decl
= DECL_ARGUMENTS (fn
);
4453 decl
; decl
= TREE_CHAIN (decl
))
4454 if (!TREE_USED (decl
) && TREE_CODE (decl
) == PARM_DECL
4455 && DECL_NAME (decl
) && !DECL_ARTIFICIAL (decl
)
4456 && !TREE_NO_WARNING (decl
))
4457 warning (OPT_Wunused_parameter
, "unused parameter %q+D", decl
);
4460 static GTY(()) rtx initial_trampoline
;
4462 /* Generate RTL for the end of the current function. */
4465 expand_function_end (void)
4469 /* If arg_pointer_save_area was referenced only from a nested
4470 function, we will not have initialized it yet. Do that now. */
4471 if (arg_pointer_save_area
&& ! crtl
->arg_pointer_save_area_init
)
4472 get_arg_pointer_save_area ();
4474 /* If we are doing generic stack checking and this function makes calls,
4475 do a stack probe at the start of the function to ensure we have enough
4476 space for another stack frame. */
4477 if (flag_stack_check
== GENERIC_STACK_CHECK
)
4481 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
4485 probe_stack_range (STACK_OLD_CHECK_PROTECT
,
4486 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE
));
4489 emit_insn_before (seq
, stack_check_probe_note
);
4494 /* End any sequences that failed to be closed due to syntax errors. */
4495 while (in_sequence_p ())
4498 clear_pending_stack_adjust ();
4499 do_pending_stack_adjust ();
4501 /* Output a linenumber for the end of the function.
4502 SDB depends on this. */
4503 force_next_line_note ();
4504 set_curr_insn_source_location (input_location
);
4506 /* Before the return label (if any), clobber the return
4507 registers so that they are not propagated live to the rest of
4508 the function. This can only happen with functions that drop
4509 through; if there had been a return statement, there would
4510 have either been a return rtx, or a jump to the return label.
4512 We delay actual code generation after the current_function_value_rtx
4514 clobber_after
= get_last_insn ();
4516 /* Output the label for the actual return from the function. */
4517 emit_label (return_label
);
4519 if (USING_SJLJ_EXCEPTIONS
)
4521 /* Let except.c know where it should emit the call to unregister
4522 the function context for sjlj exceptions. */
4523 if (flag_exceptions
)
4524 sjlj_emit_function_exit_after (get_last_insn ());
4528 /* We want to ensure that instructions that may trap are not
4529 moved into the epilogue by scheduling, because we don't
4530 always emit unwind information for the epilogue. */
4531 if (flag_non_call_exceptions
)
4532 emit_insn (gen_blockage ());
4535 /* If this is an implementation of throw, do what's necessary to
4536 communicate between __builtin_eh_return and the epilogue. */
4537 expand_eh_return ();
4539 /* If scalar return value was computed in a pseudo-reg, or was a named
4540 return value that got dumped to the stack, copy that to the hard
4542 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
4544 tree decl_result
= DECL_RESULT (current_function_decl
);
4545 rtx decl_rtl
= DECL_RTL (decl_result
);
4547 if (REG_P (decl_rtl
)
4548 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
4549 : DECL_REGISTER (decl_result
))
4551 rtx real_decl_rtl
= crtl
->return_rtx
;
4553 /* This should be set in assign_parms. */
4554 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl
));
4556 /* If this is a BLKmode structure being returned in registers,
4557 then use the mode computed in expand_return. Note that if
4558 decl_rtl is memory, then its mode may have been changed,
4559 but that crtl->return_rtx has not. */
4560 if (GET_MODE (real_decl_rtl
) == BLKmode
)
4561 PUT_MODE (real_decl_rtl
, GET_MODE (decl_rtl
));
4563 /* If a non-BLKmode return value should be padded at the least
4564 significant end of the register, shift it left by the appropriate
4565 amount. BLKmode results are handled using the group load/store
4567 if (TYPE_MODE (TREE_TYPE (decl_result
)) != BLKmode
4568 && targetm
.calls
.return_in_msb (TREE_TYPE (decl_result
)))
4570 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl
),
4571 REGNO (real_decl_rtl
)),
4573 shift_return_value (GET_MODE (decl_rtl
), true, real_decl_rtl
);
4575 /* If a named return value dumped decl_return to memory, then
4576 we may need to re-do the PROMOTE_MODE signed/unsigned
4578 else if (GET_MODE (real_decl_rtl
) != GET_MODE (decl_rtl
))
4580 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (decl_result
));
4582 if (targetm
.calls
.promote_function_return (TREE_TYPE (current_function_decl
)))
4583 promote_mode (TREE_TYPE (decl_result
), GET_MODE (decl_rtl
),
4586 convert_move (real_decl_rtl
, decl_rtl
, unsignedp
);
4588 else if (GET_CODE (real_decl_rtl
) == PARALLEL
)
4590 /* If expand_function_start has created a PARALLEL for decl_rtl,
4591 move the result to the real return registers. Otherwise, do
4592 a group load from decl_rtl for a named return. */
4593 if (GET_CODE (decl_rtl
) == PARALLEL
)
4594 emit_group_move (real_decl_rtl
, decl_rtl
);
4596 emit_group_load (real_decl_rtl
, decl_rtl
,
4597 TREE_TYPE (decl_result
),
4598 int_size_in_bytes (TREE_TYPE (decl_result
)));
4600 /* In the case of complex integer modes smaller than a word, we'll
4601 need to generate some non-trivial bitfield insertions. Do that
4602 on a pseudo and not the hard register. */
4603 else if (GET_CODE (decl_rtl
) == CONCAT
4604 && GET_MODE_CLASS (GET_MODE (decl_rtl
)) == MODE_COMPLEX_INT
4605 && GET_MODE_BITSIZE (GET_MODE (decl_rtl
)) <= BITS_PER_WORD
)
4607 int old_generating_concat_p
;
4610 old_generating_concat_p
= generating_concat_p
;
4611 generating_concat_p
= 0;
4612 tmp
= gen_reg_rtx (GET_MODE (decl_rtl
));
4613 generating_concat_p
= old_generating_concat_p
;
4615 emit_move_insn (tmp
, decl_rtl
);
4616 emit_move_insn (real_decl_rtl
, tmp
);
4619 emit_move_insn (real_decl_rtl
, decl_rtl
);
4623 /* If returning a structure, arrange to return the address of the value
4624 in a place where debuggers expect to find it.
4626 If returning a structure PCC style,
4627 the caller also depends on this value.
4628 And cfun->returns_pcc_struct is not necessarily set. */
4629 if (cfun
->returns_struct
4630 || cfun
->returns_pcc_struct
)
4632 rtx value_address
= DECL_RTL (DECL_RESULT (current_function_decl
));
4633 tree type
= TREE_TYPE (DECL_RESULT (current_function_decl
));
4636 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl
)))
4637 type
= TREE_TYPE (type
);
4639 value_address
= XEXP (value_address
, 0);
4641 outgoing
= targetm
.calls
.function_value (build_pointer_type (type
),
4642 current_function_decl
, true);
4644 /* Mark this as a function return value so integrate will delete the
4645 assignment and USE below when inlining this function. */
4646 REG_FUNCTION_VALUE_P (outgoing
) = 1;
4648 /* The address may be ptr_mode and OUTGOING may be Pmode. */
4649 value_address
= convert_memory_address (GET_MODE (outgoing
),
4652 emit_move_insn (outgoing
, value_address
);
4654 /* Show return register used to hold result (in this case the address
4656 crtl
->return_rtx
= outgoing
;
4659 /* Emit the actual code to clobber return register. */
4664 clobber_return_register ();
4665 expand_naked_return ();
4669 emit_insn_after (seq
, clobber_after
);
4672 /* Output the label for the naked return from the function. */
4673 emit_label (naked_return_label
);
4675 /* @@@ This is a kludge. We want to ensure that instructions that
4676 may trap are not moved into the epilogue by scheduling, because
4677 we don't always emit unwind information for the epilogue. */
4678 if (! USING_SJLJ_EXCEPTIONS
&& flag_non_call_exceptions
)
4679 emit_insn (gen_blockage ());
4681 /* If stack protection is enabled for this function, check the guard. */
4682 if (crtl
->stack_protect_guard
)
4683 stack_protect_epilogue ();
4685 /* If we had calls to alloca, and this machine needs
4686 an accurate stack pointer to exit the function,
4687 insert some code to save and restore the stack pointer. */
4688 if (! EXIT_IGNORE_STACK
4689 && cfun
->calls_alloca
)
4693 emit_stack_save (SAVE_FUNCTION
, &tem
, parm_birth_insn
);
4694 emit_stack_restore (SAVE_FUNCTION
, tem
, NULL_RTX
);
4697 /* ??? This should no longer be necessary since stupid is no longer with
4698 us, but there are some parts of the compiler (eg reload_combine, and
4699 sh mach_dep_reorg) that still try and compute their own lifetime info
4700 instead of using the general framework. */
4701 use_return_register ();
4705 get_arg_pointer_save_area (void)
4707 rtx ret
= arg_pointer_save_area
;
4711 ret
= assign_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0);
4712 arg_pointer_save_area
= ret
;
4715 if (! crtl
->arg_pointer_save_area_init
)
4719 /* Save the arg pointer at the beginning of the function. The
4720 generated stack slot may not be a valid memory address, so we
4721 have to check it and fix it if necessary. */
4723 emit_move_insn (validize_mem (ret
),
4724 crtl
->args
.internal_arg_pointer
);
4728 push_topmost_sequence ();
4729 emit_insn_after (seq
, entry_of_function ());
4730 pop_topmost_sequence ();
4736 /* Extend a vector that records the INSN_UIDs of INSNS
4737 (a list of one or more insns). */
4740 record_insns (rtx insns
, VEC(int,heap
) **vecp
)
4744 for (tmp
= insns
; tmp
!= NULL_RTX
; tmp
= NEXT_INSN (tmp
))
4745 VEC_safe_push (int, heap
, *vecp
, INSN_UID (tmp
));
4748 /* Set the locator of the insn chain starting at INSN to LOC. */
4750 set_insn_locators (rtx insn
, int loc
)
4752 while (insn
!= NULL_RTX
)
4755 INSN_LOCATOR (insn
) = loc
;
4756 insn
= NEXT_INSN (insn
);
4760 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
4761 be running after reorg, SEQUENCE rtl is possible. */
4764 contains (const_rtx insn
, VEC(int,heap
) **vec
)
4768 if (NONJUMP_INSN_P (insn
)
4769 && GET_CODE (PATTERN (insn
)) == SEQUENCE
)
4772 for (i
= XVECLEN (PATTERN (insn
), 0) - 1; i
>= 0; i
--)
4773 for (j
= VEC_length (int, *vec
) - 1; j
>= 0; --j
)
4774 if (INSN_UID (XVECEXP (PATTERN (insn
), 0, i
))
4775 == VEC_index (int, *vec
, j
))
4781 for (j
= VEC_length (int, *vec
) - 1; j
>= 0; --j
)
4782 if (INSN_UID (insn
) == VEC_index (int, *vec
, j
))
4789 prologue_epilogue_contains (const_rtx insn
)
4791 if (contains (insn
, &prologue
))
4793 if (contains (insn
, &epilogue
))
4799 sibcall_epilogue_contains (const_rtx insn
)
4801 if (sibcall_epilogue
)
4802 return contains (insn
, &sibcall_epilogue
);
4807 /* Insert gen_return at the end of block BB. This also means updating
4808 block_for_insn appropriately. */
4811 emit_return_into_block (basic_block bb
)
4813 emit_jump_insn_after (gen_return (), BB_END (bb
));
4815 #endif /* HAVE_return */
4817 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
4818 this into place with notes indicating where the prologue ends and where
4819 the epilogue begins. Update the basic block information when possible. */
4822 thread_prologue_and_epilogue_insns (void)
4826 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
4829 #if defined (HAVE_epilogue) || defined(HAVE_return)
4830 rtx epilogue_end
= NULL_RTX
;
4834 rtl_profile_for_bb (ENTRY_BLOCK_PTR
);
4835 #ifdef HAVE_prologue
4839 seq
= gen_prologue ();
4842 /* Insert an explicit USE for the frame pointer
4843 if the profiling is on and the frame pointer is required. */
4844 if (crtl
->profile
&& frame_pointer_needed
)
4845 emit_use (hard_frame_pointer_rtx
);
4847 /* Retain a map of the prologue insns. */
4848 record_insns (seq
, &prologue
);
4849 emit_note (NOTE_INSN_PROLOGUE_END
);
4851 #ifndef PROFILE_BEFORE_PROLOGUE
4852 /* Ensure that instructions are not moved into the prologue when
4853 profiling is on. The call to the profiling routine can be
4854 emitted within the live range of a call-clobbered register. */
4856 emit_insn (gen_blockage ());
4861 set_insn_locators (seq
, prologue_locator
);
4863 /* Can't deal with multiple successors of the entry block
4864 at the moment. Function should always have at least one
4866 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR
));
4868 insert_insn_on_edge (seq
, single_succ_edge (ENTRY_BLOCK_PTR
));
4873 /* If the exit block has no non-fake predecessors, we don't need
4875 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
4876 if ((e
->flags
& EDGE_FAKE
) == 0)
4881 rtl_profile_for_bb (EXIT_BLOCK_PTR
);
4883 if (optimize
&& HAVE_return
)
4885 /* If we're allowed to generate a simple return instruction,
4886 then by definition we don't need a full epilogue. Examine
4887 the block that falls through to EXIT. If it does not
4888 contain any code, examine its predecessors and try to
4889 emit (conditional) return instructions. */
4894 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
4895 if (e
->flags
& EDGE_FALLTHRU
)
4901 /* Verify that there are no active instructions in the last block. */
4902 label
= BB_END (last
);
4903 while (label
&& !LABEL_P (label
))
4905 if (active_insn_p (label
))
4907 label
= PREV_INSN (label
);
4910 if (BB_HEAD (last
) == label
&& LABEL_P (label
))
4914 for (ei2
= ei_start (last
->preds
); (e
= ei_safe_edge (ei2
)); )
4916 basic_block bb
= e
->src
;
4919 if (bb
== ENTRY_BLOCK_PTR
)
4926 if (!JUMP_P (jump
) || JUMP_LABEL (jump
) != label
)
4932 /* If we have an unconditional jump, we can replace that
4933 with a simple return instruction. */
4934 if (simplejump_p (jump
))
4936 emit_return_into_block (bb
);
4940 /* If we have a conditional jump, we can try to replace
4941 that with a conditional return instruction. */
4942 else if (condjump_p (jump
))
4944 if (! redirect_jump (jump
, 0, 0))
4950 /* If this block has only one successor, it both jumps
4951 and falls through to the fallthru block, so we can't
4953 if (single_succ_p (bb
))
4965 /* Fix up the CFG for the successful change we just made. */
4966 redirect_edge_succ (e
, EXIT_BLOCK_PTR
);
4969 /* Emit a return insn for the exit fallthru block. Whether
4970 this is still reachable will be determined later. */
4972 emit_barrier_after (BB_END (last
));
4973 emit_return_into_block (last
);
4974 epilogue_end
= BB_END (last
);
4975 single_succ_edge (last
)->flags
&= ~EDGE_FALLTHRU
;
4980 /* Find the edge that falls through to EXIT. Other edges may exist
4981 due to RETURN instructions, but those don't need epilogues.
4982 There really shouldn't be a mixture -- either all should have
4983 been converted or none, however... */
4985 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
4986 if (e
->flags
& EDGE_FALLTHRU
)
4991 #ifdef HAVE_epilogue
4995 epilogue_end
= emit_note (NOTE_INSN_EPILOGUE_BEG
);
4996 seq
= gen_epilogue ();
4997 emit_jump_insn (seq
);
4999 /* Retain a map of the epilogue insns. */
5000 record_insns (seq
, &epilogue
);
5001 set_insn_locators (seq
, epilogue_locator
);
5006 insert_insn_on_edge (seq
, e
);
5014 if (! next_active_insn (BB_END (e
->src
)))
5016 /* We have a fall-through edge to the exit block, the source is not
5017 at the end of the function, and there will be an assembler epilogue
5018 at the end of the function.
5019 We can't use force_nonfallthru here, because that would try to
5020 use return. Inserting a jump 'by hand' is extremely messy, so
5021 we take advantage of cfg_layout_finalize using
5022 fixup_fallthru_exit_predecessor. */
5023 cfg_layout_initialize (0);
5024 FOR_EACH_BB (cur_bb
)
5025 if (cur_bb
->index
>= NUM_FIXED_BLOCKS
5026 && cur_bb
->next_bb
->index
>= NUM_FIXED_BLOCKS
)
5027 cur_bb
->aux
= cur_bb
->next_bb
;
5028 cfg_layout_finalize ();
5031 default_rtl_profile ();
5035 commit_edge_insertions ();
5037 /* The epilogue insns we inserted may cause the exit edge to no longer
5039 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5041 if (((e
->flags
& EDGE_FALLTHRU
) != 0)
5042 && returnjump_p (BB_END (e
->src
)))
5043 e
->flags
&= ~EDGE_FALLTHRU
;
5047 #ifdef HAVE_sibcall_epilogue
5048 /* Emit sibling epilogues before any sibling call sites. */
5049 for (ei
= ei_start (EXIT_BLOCK_PTR
->preds
); (e
= ei_safe_edge (ei
)); )
5051 basic_block bb
= e
->src
;
5052 rtx insn
= BB_END (bb
);
5055 || ! SIBLING_CALL_P (insn
))
5062 emit_insn (gen_sibcall_epilogue ());
5066 /* Retain a map of the epilogue insns. Used in life analysis to
5067 avoid getting rid of sibcall epilogue insns. Do this before we
5068 actually emit the sequence. */
5069 record_insns (seq
, &sibcall_epilogue
);
5070 set_insn_locators (seq
, epilogue_locator
);
5072 emit_insn_before (seq
, insn
);
5077 #ifdef HAVE_epilogue
5082 /* Similarly, move any line notes that appear after the epilogue.
5083 There is no need, however, to be quite so anal about the existence
5084 of such a note. Also possibly move
5085 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
5087 for (insn
= epilogue_end
; insn
; insn
= next
)
5089 next
= NEXT_INSN (insn
);
5091 && (NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
))
5092 reorder_insns (insn
, insn
, PREV_INSN (epilogue_end
));
5097 /* Threading the prologue and epilogue changes the artificial refs
5098 in the entry and exit blocks. */
5099 epilogue_completed
= 1;
5100 df_update_entry_exit_and_calls ();
5103 /* Reposition the prologue-end and epilogue-begin notes after instruction
5104 scheduling and delayed branch scheduling. */
5107 reposition_prologue_and_epilogue_notes (void)
5109 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
5110 rtx insn
, last
, note
;
5113 if ((len
= VEC_length (int, prologue
)) > 0)
5117 /* Scan from the beginning until we reach the last prologue insn.
5118 We apparently can't depend on basic_block_{head,end} after
5120 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
5124 if (NOTE_KIND (insn
) == NOTE_INSN_PROLOGUE_END
)
5127 else if (contains (insn
, &prologue
))
5137 /* Find the prologue-end note if we haven't already, and
5138 move it to just after the last prologue insn. */
5141 for (note
= last
; (note
= NEXT_INSN (note
));)
5143 && NOTE_KIND (note
) == NOTE_INSN_PROLOGUE_END
)
5147 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
5149 last
= NEXT_INSN (last
);
5150 reorder_insns (note
, note
, last
);
5154 if ((len
= VEC_length (int, epilogue
)) > 0)
5158 /* Scan from the end until we reach the first epilogue insn.
5159 We apparently can't depend on basic_block_{head,end} after
5161 for (insn
= get_last_insn (); insn
; insn
= PREV_INSN (insn
))
5165 if (NOTE_KIND (insn
) == NOTE_INSN_EPILOGUE_BEG
)
5168 else if (contains (insn
, &epilogue
))
5178 /* Find the epilogue-begin note if we haven't already, and
5179 move it to just before the first epilogue insn. */
5182 for (note
= insn
; (note
= PREV_INSN (note
));)
5184 && NOTE_KIND (note
) == NOTE_INSN_EPILOGUE_BEG
)
5188 if (PREV_INSN (last
) != note
)
5189 reorder_insns (note
, note
, PREV_INSN (last
));
5192 #endif /* HAVE_prologue or HAVE_epilogue */
5195 /* Returns the name of the current function. */
5197 current_function_name (void)
5199 return lang_hooks
.decl_printable_name (cfun
->decl
, 2);
5202 /* Returns the raw (mangled) name of the current function. */
5204 current_function_assembler_name (void)
5206 return IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (cfun
->decl
));
5211 rest_of_handle_check_leaf_regs (void)
5213 #ifdef LEAF_REGISTERS
5214 current_function_uses_only_leaf_regs
5215 = optimize
> 0 && only_leaf_regs_used () && leaf_function_p ();
5220 /* Insert a TYPE into the used types hash table of CFUN. */
5222 used_types_insert_helper (tree type
, struct function
*func
)
5224 if (type
!= NULL
&& func
!= NULL
)
5228 if (func
->used_types_hash
== NULL
)
5229 func
->used_types_hash
= htab_create_ggc (37, htab_hash_pointer
,
5230 htab_eq_pointer
, NULL
);
5231 slot
= htab_find_slot (func
->used_types_hash
, type
, INSERT
);
5237 /* Given a type, insert it into the used hash table in cfun. */
5239 used_types_insert (tree t
)
5241 while (POINTER_TYPE_P (t
) || TREE_CODE (t
) == ARRAY_TYPE
)
5243 t
= TYPE_MAIN_VARIANT (t
);
5244 if (debug_info_level
> DINFO_LEVEL_NONE
)
5245 used_types_insert_helper (t
, cfun
);
5248 struct rtl_opt_pass pass_leaf_regs
=
5254 rest_of_handle_check_leaf_regs
, /* execute */
5257 0, /* static_pass_number */
5259 0, /* properties_required */
5260 0, /* properties_provided */
5261 0, /* properties_destroyed */
5262 0, /* todo_flags_start */
5263 0 /* todo_flags_finish */
5268 rest_of_handle_thread_prologue_and_epilogue (void)
5271 cleanup_cfg (CLEANUP_EXPENSIVE
);
5272 /* On some machines, the prologue and epilogue code, or parts thereof,
5273 can be represented as RTL. Doing so lets us schedule insns between
5274 it and the rest of the code and also allows delayed branch
5275 scheduling to operate in the epilogue. */
5277 thread_prologue_and_epilogue_insns ();
5281 struct rtl_opt_pass pass_thread_prologue_and_epilogue
=
5285 "pro_and_epilogue", /* name */
5287 rest_of_handle_thread_prologue_and_epilogue
, /* execute */
5290 0, /* static_pass_number */
5291 TV_THREAD_PROLOGUE_AND_EPILOGUE
, /* tv_id */
5292 0, /* properties_required */
5293 0, /* properties_provided */
5294 0, /* properties_destroyed */
5295 TODO_verify_flow
, /* todo_flags_start */
5298 TODO_df_finish
| TODO_verify_rtl_sharing
|
5299 TODO_ggc_collect
/* todo_flags_finish */
5304 /* This mini-pass fixes fall-out from SSA in asm statements that have
5305 in-out constraints. Say you start with
5308 asm ("": "+mr" (inout));
5311 which is transformed very early to use explicit output and match operands:
5314 asm ("": "=mr" (inout) : "0" (inout));
5317 Or, after SSA and copyprop,
5319 asm ("": "=mr" (inout_2) : "0" (inout_1));
5322 Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
5323 they represent two separate values, so they will get different pseudo
5324 registers during expansion. Then, since the two operands need to match
5325 per the constraints, but use different pseudo registers, reload can
5326 only register a reload for these operands. But reloads can only be
5327 satisfied by hardregs, not by memory, so we need a register for this
5328 reload, just because we are presented with non-matching operands.
5329 So, even though we allow memory for this operand, no memory can be
5330 used for it, just because the two operands don't match. This can
5331 cause reload failures on register-starved targets.
5333 So it's a symptom of reload not being able to use memory for reloads
5334 or, alternatively it's also a symptom of both operands not coming into
5335 reload as matching (in which case the pseudo could go to memory just
5336 fine, as the alternative allows it, and no reload would be necessary).
5337 We fix the latter problem here, by transforming
5339 asm ("": "=mr" (inout_2) : "0" (inout_1));
5344 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
5347 match_asm_constraints_1 (rtx insn
, rtx
*p_sets
, int noutputs
)
5350 bool changed
= false;
5351 rtx op
= SET_SRC (p_sets
[0]);
5352 int ninputs
= ASM_OPERANDS_INPUT_LENGTH (op
);
5353 rtvec inputs
= ASM_OPERANDS_INPUT_VEC (op
);
5354 bool *output_matched
= XALLOCAVEC (bool, noutputs
);
5356 memset (output_matched
, 0, noutputs
* sizeof (bool));
5357 for (i
= 0; i
< ninputs
; i
++)
5359 rtx input
, output
, insns
;
5360 const char *constraint
= ASM_OPERANDS_INPUT_CONSTRAINT (op
, i
);
5364 match
= strtoul (constraint
, &end
, 10);
5365 if (end
== constraint
)
5368 gcc_assert (match
< noutputs
);
5369 output
= SET_DEST (p_sets
[match
]);
5370 input
= RTVEC_ELT (inputs
, i
);
5371 /* Only do the transformation for pseudos. */
5372 if (! REG_P (output
)
5373 || rtx_equal_p (output
, input
)
5374 || (GET_MODE (input
) != VOIDmode
5375 && GET_MODE (input
) != GET_MODE (output
)))
5378 /* We can't do anything if the output is also used as input,
5379 as we're going to overwrite it. */
5380 for (j
= 0; j
< ninputs
; j
++)
5381 if (reg_overlap_mentioned_p (output
, RTVEC_ELT (inputs
, j
)))
5386 /* Avoid changing the same input several times. For
5387 asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
5388 only change in once (to out1), rather than changing it
5389 first to out1 and afterwards to out2. */
5392 for (j
= 0; j
< noutputs
; j
++)
5393 if (output_matched
[j
] && input
== SET_DEST (p_sets
[j
]))
5398 output_matched
[match
] = true;
5401 emit_move_insn (output
, input
);
5402 insns
= get_insns ();
5404 emit_insn_before (insns
, insn
);
5406 /* Now replace all mentions of the input with output. We can't
5407 just replace the occurrence in inputs[i], as the register might
5408 also be used in some other input (or even in an address of an
5409 output), which would mean possibly increasing the number of
5410 inputs by one (namely 'output' in addition), which might pose
5411 a too complicated problem for reload to solve. E.g. this situation:
5413 asm ("" : "=r" (output), "=m" (input) : "0" (input))
5415 Here 'input' is used in two occurrences as input (once for the
5416 input operand, once for the address in the second output operand).
5417 If we would replace only the occurrence of the input operand (to
5418 make the matching) we would be left with this:
5421 asm ("" : "=r" (output), "=m" (input) : "0" (output))
5423 Now we suddenly have two different input values (containing the same
5424 value, but different pseudos) where we formerly had only one.
5425 With more complicated asms this might lead to reload failures
5426 which wouldn't have happen without this pass. So, iterate over
5427 all operands and replace all occurrences of the register used. */
5428 for (j
= 0; j
< noutputs
; j
++)
5429 if (!rtx_equal_p (SET_DEST (p_sets
[j
]), input
)
5430 && reg_overlap_mentioned_p (input
, SET_DEST (p_sets
[j
])))
5431 SET_DEST (p_sets
[j
]) = replace_rtx (SET_DEST (p_sets
[j
]),
5433 for (j
= 0; j
< ninputs
; j
++)
5434 if (reg_overlap_mentioned_p (input
, RTVEC_ELT (inputs
, j
)))
5435 RTVEC_ELT (inputs
, j
) = replace_rtx (RTVEC_ELT (inputs
, j
),
5442 df_insn_rescan (insn
);
5446 rest_of_match_asm_constraints (void)
5449 rtx insn
, pat
, *p_sets
;
5452 if (!crtl
->has_asm_statement
)
5455 df_set_flags (DF_DEFER_INSN_RESCAN
);
5458 FOR_BB_INSNS (bb
, insn
)
5463 pat
= PATTERN (insn
);
5464 if (GET_CODE (pat
) == PARALLEL
)
5465 p_sets
= &XVECEXP (pat
, 0, 0), noutputs
= XVECLEN (pat
, 0);
5466 else if (GET_CODE (pat
) == SET
)
5467 p_sets
= &PATTERN (insn
), noutputs
= 1;
5471 if (GET_CODE (*p_sets
) == SET
5472 && GET_CODE (SET_SRC (*p_sets
)) == ASM_OPERANDS
)
5473 match_asm_constraints_1 (insn
, p_sets
, noutputs
);
5477 return TODO_df_finish
;
5480 struct rtl_opt_pass pass_match_asm_constraints
=
5484 "asmcons", /* name */
5486 rest_of_match_asm_constraints
, /* execute */
5489 0, /* static_pass_number */
5491 0, /* properties_required */
5492 0, /* properties_provided */
5493 0, /* properties_destroyed */
5494 0, /* todo_flags_start */
5495 TODO_dump_func
/* todo_flags_finish */
5500 #include "gt-function.h"