1 /* Expands front end tree to back end RTL for GCC.
2 Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
4 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
22 /* This file handles the generation of rtl code from tree structure
23 at the level of the function as a whole.
24 It creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 `expand_function_start' is called at the beginning of a function,
28 before the function body is parsed, and `expand_function_end' is
29 called after parsing the body.
31 Call `assign_stack_local' to allocate a stack slot for a local variable.
32 This is usually done during the RTL generation for the function body,
33 but it can also be done in the reload pass when a pseudo-register does
34 not get a hard register. */
38 #include "coretypes.h"
49 #include "hard-reg-set.h"
50 #include "insn-config.h"
53 #include "basic-block.h"
58 #include "integrate.h"
59 #include "langhooks.h"
61 #include "cfglayout.h"
63 #include "tree-pass.h"
69 /* So we can assign to cfun in this file. */
72 #ifndef STACK_ALIGNMENT_NEEDED
73 #define STACK_ALIGNMENT_NEEDED 1
76 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
78 /* Some systems use __main in a way incompatible with its use in gcc, in these
79 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
80 give the same symbol without quotes for an alternative entry point. You
81 must define both, or neither. */
83 #define NAME__MAIN "__main"
86 /* Round a value to the lowest integer less than it that is a multiple of
87 the required alignment. Avoid using division in case the value is
88 negative. Assume the alignment is a power of two. */
89 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
91 /* Similar, but round to the next highest integer that meets the
93 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
95 /* Nonzero if function being compiled doesn't contain any calls
96 (ignoring the prologue and epilogue). This is set prior to
97 local register allocation and is valid for the remaining
99 int current_function_is_leaf
;
101 /* Nonzero if function being compiled doesn't modify the stack pointer
102 (ignoring the prologue and epilogue). This is only valid after
103 pass_stack_ptr_mod has run. */
104 int current_function_sp_is_unchanging
;
106 /* Nonzero if the function being compiled is a leaf function which only
107 uses leaf registers. This is valid after reload (specifically after
108 sched2) and is useful only if the port defines LEAF_REGISTERS. */
109 int current_function_uses_only_leaf_regs
;
111 /* Nonzero once virtual register instantiation has been done.
112 assign_stack_local uses frame_pointer_rtx when this is nonzero.
113 calls.c:emit_library_call_value_1 uses it to set up
114 post-instantiation libcalls. */
115 int virtuals_instantiated
;
117 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
118 static GTY(()) int funcdef_no
;
120 /* These variables hold pointers to functions to create and destroy
121 target specific, per-function data structures. */
122 struct machine_function
* (*init_machine_status
) (void);
124 /* The currently compiled function. */
125 struct function
*cfun
= 0;
127 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
128 static VEC(int,heap
) *prologue
;
129 static VEC(int,heap
) *epilogue
;
131 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
133 static VEC(int,heap
) *sibcall_epilogue
;
135 /* In order to evaluate some expressions, such as function calls returning
136 structures in memory, we need to temporarily allocate stack locations.
137 We record each allocated temporary in the following structure.
139 Associated with each temporary slot is a nesting level. When we pop up
140 one level, all temporaries associated with the previous level are freed.
141 Normally, all temporaries are freed after the execution of the statement
142 in which they were created. However, if we are inside a ({...}) grouping,
143 the result may be in a temporary and hence must be preserved. If the
144 result could be in a temporary, we preserve it if we can determine which
145 one it is in. If we cannot determine which temporary may contain the
146 result, all temporaries are preserved. A temporary is preserved by
147 pretending it was allocated at the previous nesting level.
149 Automatic variables are also assigned temporary slots, at the nesting
150 level where they are defined. They are marked a "kept" so that
151 free_temp_slots will not free them. */
153 struct temp_slot
GTY(())
155 /* Points to next temporary slot. */
156 struct temp_slot
*next
;
157 /* Points to previous temporary slot. */
158 struct temp_slot
*prev
;
160 /* The rtx to used to reference the slot. */
162 /* The rtx used to represent the address if not the address of the
163 slot above. May be an EXPR_LIST if multiple addresses exist. */
165 /* The alignment (in bits) of the slot. */
167 /* The size, in units, of the slot. */
169 /* The type of the object in the slot, or zero if it doesn't correspond
170 to a type. We use this to determine whether a slot can be reused.
171 It can be reused if objects of the type of the new slot will always
172 conflict with objects of the type of the old slot. */
174 /* Nonzero if this temporary is currently in use. */
176 /* Nonzero if this temporary has its address taken. */
178 /* Nesting level at which this slot is being used. */
180 /* Nonzero if this should survive a call to free_temp_slots. */
182 /* The offset of the slot from the frame_pointer, including extra space
183 for alignment. This info is for combine_temp_slots. */
184 HOST_WIDE_INT base_offset
;
185 /* The size of the slot, including extra space for alignment. This
186 info is for combine_temp_slots. */
187 HOST_WIDE_INT full_size
;
190 /* Forward declarations. */
192 static struct temp_slot
*find_temp_slot_from_address (rtx
);
193 static void pad_to_arg_alignment (struct args_size
*, int, struct args_size
*);
194 static void pad_below (struct args_size
*, enum machine_mode
, tree
);
195 static void reorder_blocks_1 (rtx
, tree
, VEC(tree
,heap
) **);
196 static int all_blocks (tree
, tree
*);
197 static tree
*get_block_vector (tree
, int *);
198 extern tree
debug_find_var_in_block_tree (tree
, tree
);
199 /* We always define `record_insns' even if it's not used so that we
200 can always export `prologue_epilogue_contains'. */
201 static void record_insns (rtx
, VEC(int,heap
) **) ATTRIBUTE_UNUSED
;
202 static int contains (const_rtx
, VEC(int,heap
) **);
204 static void emit_return_into_block (basic_block
);
206 static void prepare_function_start (void);
207 static void do_clobber_return_reg (rtx
, void *);
208 static void do_use_return_reg (rtx
, void *);
209 static void set_insn_locators (rtx
, int) ATTRIBUTE_UNUSED
;
211 /* Pointer to chain of `struct function' for containing functions. */
212 struct function
*outer_function_chain
;
214 /* Given a function decl for a containing function,
215 return the `struct function' for it. */
218 find_function_data (tree decl
)
222 for (p
= outer_function_chain
; p
; p
= p
->outer
)
229 /* Save the current context for compilation of a nested function.
230 This is called from language-specific code. */
233 push_function_context (void)
236 allocate_struct_function (NULL
, false);
238 cfun
->outer
= outer_function_chain
;
239 outer_function_chain
= cfun
;
243 /* Restore the last saved context, at the end of a nested function.
244 This function is called from language-specific code. */
247 pop_function_context (void)
249 struct function
*p
= outer_function_chain
;
252 outer_function_chain
= p
->outer
;
253 current_function_decl
= p
->decl
;
255 /* Reset variables that have known state during rtx generation. */
256 virtuals_instantiated
= 0;
257 generating_concat_p
= 1;
260 /* Clear out all parts of the state in F that can safely be discarded
261 after the function has been parsed, but not compiled, to let
262 garbage collection reclaim the memory. */
265 free_after_parsing (struct function
*f
)
270 /* Clear out all parts of the state in F that can safely be discarded
271 after the function has been compiled, to let garbage collection
272 reclaim the memory. */
275 free_after_compilation (struct function
*f
)
277 VEC_free (int, heap
, prologue
);
278 VEC_free (int, heap
, epilogue
);
279 VEC_free (int, heap
, sibcall_epilogue
);
280 if (crtl
->emit
.regno_pointer_align
)
281 free (crtl
->emit
.regno_pointer_align
);
283 memset (crtl
, 0, sizeof (struct rtl_data
));
288 regno_reg_rtx
= NULL
;
289 insn_locators_free ();
292 /* Return size needed for stack frame based on slots so far allocated.
293 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
294 the caller may have to do that. */
297 get_frame_size (void)
299 if (FRAME_GROWS_DOWNWARD
)
300 return -frame_offset
;
305 /* Issue an error message and return TRUE if frame OFFSET overflows in
306 the signed target pointer arithmetics for function FUNC. Otherwise
310 frame_offset_overflow (HOST_WIDE_INT offset
, tree func
)
312 unsigned HOST_WIDE_INT size
= FRAME_GROWS_DOWNWARD
? -offset
: offset
;
314 if (size
> ((unsigned HOST_WIDE_INT
) 1 << (GET_MODE_BITSIZE (Pmode
) - 1))
315 /* Leave room for the fixed part of the frame. */
316 - 64 * UNITS_PER_WORD
)
318 error ("%Jtotal size of local objects too large", func
);
325 /* Return stack slot alignment in bits for TYPE and MODE. */
328 get_stack_local_alignment (tree type
, enum machine_mode mode
)
330 unsigned int alignment
;
333 alignment
= BIGGEST_ALIGNMENT
;
335 alignment
= GET_MODE_ALIGNMENT (mode
);
337 /* Allow the frond-end to (possibly) increase the alignment of this
340 type
= lang_hooks
.types
.type_for_mode (mode
, 0);
342 return STACK_SLOT_ALIGNMENT (type
, mode
, alignment
);
345 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
346 with machine mode MODE.
348 ALIGN controls the amount of alignment for the address of the slot:
349 0 means according to MODE,
350 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
351 -2 means use BITS_PER_UNIT,
352 positive specifies alignment boundary in bits.
354 If REDUCE_ALIGNMENT_OK is true, it is OK to reduce alignment.
356 We do not round to stack_boundary here. */
359 assign_stack_local_1 (enum machine_mode mode
, HOST_WIDE_INT size
,
361 bool reduce_alignment_ok ATTRIBUTE_UNUSED
)
364 int bigend_correction
= 0;
365 unsigned int alignment
, alignment_in_bits
;
366 int frame_off
, frame_alignment
, frame_phase
;
370 alignment
= get_stack_local_alignment (NULL
, mode
);
371 alignment
/= BITS_PER_UNIT
;
373 else if (align
== -1)
375 alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
376 size
= CEIL_ROUND (size
, alignment
);
378 else if (align
== -2)
379 alignment
= 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
381 alignment
= align
/ BITS_PER_UNIT
;
383 alignment_in_bits
= alignment
* BITS_PER_UNIT
;
385 if (FRAME_GROWS_DOWNWARD
)
386 frame_offset
-= size
;
388 /* Ignore alignment if it exceeds MAX_SUPPORTED_STACK_ALIGNMENT. */
389 if (alignment_in_bits
> MAX_SUPPORTED_STACK_ALIGNMENT
)
391 alignment_in_bits
= MAX_SUPPORTED_STACK_ALIGNMENT
;
392 alignment
= alignment_in_bits
/ BITS_PER_UNIT
;
395 if (SUPPORTS_STACK_ALIGNMENT
)
397 if (crtl
->stack_alignment_estimated
< alignment_in_bits
)
399 if (!crtl
->stack_realign_processed
)
400 crtl
->stack_alignment_estimated
= alignment_in_bits
;
403 /* If stack is realigned and stack alignment value
404 hasn't been finalized, it is OK not to increase
405 stack_alignment_estimated. The bigger alignment
406 requirement is recorded in stack_alignment_needed
408 gcc_assert (!crtl
->stack_realign_finalized
);
409 if (!crtl
->stack_realign_needed
)
411 /* It is OK to reduce the alignment as long as the
412 requested size is 0 or the estimated stack
413 alignment >= mode alignment. */
414 gcc_assert (reduce_alignment_ok
416 || (crtl
->stack_alignment_estimated
417 >= GET_MODE_ALIGNMENT (mode
)));
418 alignment_in_bits
= crtl
->stack_alignment_estimated
;
419 alignment
= alignment_in_bits
/ BITS_PER_UNIT
;
425 if (crtl
->stack_alignment_needed
< alignment_in_bits
)
426 crtl
->stack_alignment_needed
= alignment_in_bits
;
427 if (crtl
->max_used_stack_slot_alignment
< crtl
->stack_alignment_needed
)
428 crtl
->max_used_stack_slot_alignment
= crtl
->stack_alignment_needed
;
430 /* Calculate how many bytes the start of local variables is off from
432 frame_alignment
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
433 frame_off
= STARTING_FRAME_OFFSET
% frame_alignment
;
434 frame_phase
= frame_off
? frame_alignment
- frame_off
: 0;
436 /* Round the frame offset to the specified alignment. The default is
437 to always honor requests to align the stack but a port may choose to
438 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
439 if (STACK_ALIGNMENT_NEEDED
443 /* We must be careful here, since FRAME_OFFSET might be negative and
444 division with a negative dividend isn't as well defined as we might
445 like. So we instead assume that ALIGNMENT is a power of two and
446 use logical operations which are unambiguous. */
447 if (FRAME_GROWS_DOWNWARD
)
449 = (FLOOR_ROUND (frame_offset
- frame_phase
,
450 (unsigned HOST_WIDE_INT
) alignment
)
454 = (CEIL_ROUND (frame_offset
- frame_phase
,
455 (unsigned HOST_WIDE_INT
) alignment
)
459 /* On a big-endian machine, if we are allocating more space than we will use,
460 use the least significant bytes of those that are allocated. */
461 if (BYTES_BIG_ENDIAN
&& mode
!= BLKmode
&& GET_MODE_SIZE (mode
) < size
)
462 bigend_correction
= size
- GET_MODE_SIZE (mode
);
464 /* If we have already instantiated virtual registers, return the actual
465 address relative to the frame pointer. */
466 if (virtuals_instantiated
)
467 addr
= plus_constant (frame_pointer_rtx
,
469 (frame_offset
+ bigend_correction
470 + STARTING_FRAME_OFFSET
, Pmode
));
472 addr
= plus_constant (virtual_stack_vars_rtx
,
474 (frame_offset
+ bigend_correction
,
477 if (!FRAME_GROWS_DOWNWARD
)
478 frame_offset
+= size
;
480 x
= gen_rtx_MEM (mode
, addr
);
481 set_mem_align (x
, alignment_in_bits
);
482 MEM_NOTRAP_P (x
) = 1;
485 = gen_rtx_EXPR_LIST (VOIDmode
, x
, stack_slot_list
);
487 if (frame_offset_overflow (frame_offset
, current_function_decl
))
493 /* Wrap up assign_stack_local_1 with last parameter as false. */
496 assign_stack_local (enum machine_mode mode
, HOST_WIDE_INT size
, int align
)
498 return assign_stack_local_1 (mode
, size
, align
, false);
501 /* Removes temporary slot TEMP from LIST. */
504 cut_slot_from_list (struct temp_slot
*temp
, struct temp_slot
**list
)
507 temp
->next
->prev
= temp
->prev
;
509 temp
->prev
->next
= temp
->next
;
513 temp
->prev
= temp
->next
= NULL
;
516 /* Inserts temporary slot TEMP to LIST. */
519 insert_slot_to_list (struct temp_slot
*temp
, struct temp_slot
**list
)
523 (*list
)->prev
= temp
;
528 /* Returns the list of used temp slots at LEVEL. */
530 static struct temp_slot
**
531 temp_slots_at_level (int level
)
533 if (level
>= (int) VEC_length (temp_slot_p
, used_temp_slots
))
534 VEC_safe_grow_cleared (temp_slot_p
, gc
, used_temp_slots
, level
+ 1);
536 return &(VEC_address (temp_slot_p
, used_temp_slots
)[level
]);
539 /* Returns the maximal temporary slot level. */
542 max_slot_level (void)
544 if (!used_temp_slots
)
547 return VEC_length (temp_slot_p
, used_temp_slots
) - 1;
550 /* Moves temporary slot TEMP to LEVEL. */
553 move_slot_to_level (struct temp_slot
*temp
, int level
)
555 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
556 insert_slot_to_list (temp
, temp_slots_at_level (level
));
560 /* Make temporary slot TEMP available. */
563 make_slot_available (struct temp_slot
*temp
)
565 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
566 insert_slot_to_list (temp
, &avail_temp_slots
);
571 /* Allocate a temporary stack slot and record it for possible later
574 MODE is the machine mode to be given to the returned rtx.
576 SIZE is the size in units of the space required. We do no rounding here
577 since assign_stack_local will do any required rounding.
579 KEEP is 1 if this slot is to be retained after a call to
580 free_temp_slots. Automatic variables for a block are allocated
581 with this flag. KEEP values of 2 or 3 were needed respectively
582 for variables whose lifetime is controlled by CLEANUP_POINT_EXPRs
583 or for SAVE_EXPRs, but they are now unused.
585 TYPE is the type that will be used for the stack slot. */
588 assign_stack_temp_for_type (enum machine_mode mode
, HOST_WIDE_INT size
,
592 struct temp_slot
*p
, *best_p
= 0, *selected
= NULL
, **pp
;
595 /* If SIZE is -1 it means that somebody tried to allocate a temporary
596 of a variable size. */
597 gcc_assert (size
!= -1);
599 /* These are now unused. */
600 gcc_assert (keep
<= 1);
602 align
= get_stack_local_alignment (type
, mode
);
604 /* Try to find an available, already-allocated temporary of the proper
605 mode which meets the size and alignment requirements. Choose the
606 smallest one with the closest alignment.
608 If assign_stack_temp is called outside of the tree->rtl expansion,
609 we cannot reuse the stack slots (that may still refer to
610 VIRTUAL_STACK_VARS_REGNUM). */
611 if (!virtuals_instantiated
)
613 for (p
= avail_temp_slots
; p
; p
= p
->next
)
615 if (p
->align
>= align
&& p
->size
>= size
616 && GET_MODE (p
->slot
) == mode
617 && objects_must_conflict_p (p
->type
, type
)
618 && (best_p
== 0 || best_p
->size
> p
->size
619 || (best_p
->size
== p
->size
&& best_p
->align
> p
->align
)))
621 if (p
->align
== align
&& p
->size
== size
)
624 cut_slot_from_list (selected
, &avail_temp_slots
);
633 /* Make our best, if any, the one to use. */
637 cut_slot_from_list (selected
, &avail_temp_slots
);
639 /* If there are enough aligned bytes left over, make them into a new
640 temp_slot so that the extra bytes don't get wasted. Do this only
641 for BLKmode slots, so that we can be sure of the alignment. */
642 if (GET_MODE (best_p
->slot
) == BLKmode
)
644 int alignment
= best_p
->align
/ BITS_PER_UNIT
;
645 HOST_WIDE_INT rounded_size
= CEIL_ROUND (size
, alignment
);
647 if (best_p
->size
- rounded_size
>= alignment
)
649 p
= GGC_NEW (struct temp_slot
);
650 p
->in_use
= p
->addr_taken
= 0;
651 p
->size
= best_p
->size
- rounded_size
;
652 p
->base_offset
= best_p
->base_offset
+ rounded_size
;
653 p
->full_size
= best_p
->full_size
- rounded_size
;
654 p
->slot
= adjust_address_nv (best_p
->slot
, BLKmode
, rounded_size
);
655 p
->align
= best_p
->align
;
657 p
->type
= best_p
->type
;
658 insert_slot_to_list (p
, &avail_temp_slots
);
660 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, p
->slot
,
663 best_p
->size
= rounded_size
;
664 best_p
->full_size
= rounded_size
;
669 /* If we still didn't find one, make a new temporary. */
672 HOST_WIDE_INT frame_offset_old
= frame_offset
;
674 p
= GGC_NEW (struct temp_slot
);
676 /* We are passing an explicit alignment request to assign_stack_local.
677 One side effect of that is assign_stack_local will not round SIZE
678 to ensure the frame offset remains suitably aligned.
680 So for requests which depended on the rounding of SIZE, we go ahead
681 and round it now. We also make sure ALIGNMENT is at least
682 BIGGEST_ALIGNMENT. */
683 gcc_assert (mode
!= BLKmode
|| align
== BIGGEST_ALIGNMENT
);
684 p
->slot
= assign_stack_local (mode
,
686 ? CEIL_ROUND (size
, (int) align
/ BITS_PER_UNIT
)
692 /* The following slot size computation is necessary because we don't
693 know the actual size of the temporary slot until assign_stack_local
694 has performed all the frame alignment and size rounding for the
695 requested temporary. Note that extra space added for alignment
696 can be either above or below this stack slot depending on which
697 way the frame grows. We include the extra space if and only if it
698 is above this slot. */
699 if (FRAME_GROWS_DOWNWARD
)
700 p
->size
= frame_offset_old
- frame_offset
;
704 /* Now define the fields used by combine_temp_slots. */
705 if (FRAME_GROWS_DOWNWARD
)
707 p
->base_offset
= frame_offset
;
708 p
->full_size
= frame_offset_old
- frame_offset
;
712 p
->base_offset
= frame_offset_old
;
713 p
->full_size
= frame_offset
- frame_offset_old
;
724 p
->level
= temp_slot_level
;
727 pp
= temp_slots_at_level (p
->level
);
728 insert_slot_to_list (p
, pp
);
730 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
731 slot
= gen_rtx_MEM (mode
, XEXP (p
->slot
, 0));
732 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, slot
, stack_slot_list
);
734 /* If we know the alias set for the memory that will be used, use
735 it. If there's no TYPE, then we don't know anything about the
736 alias set for the memory. */
737 set_mem_alias_set (slot
, type
? get_alias_set (type
) : 0);
738 set_mem_align (slot
, align
);
740 /* If a type is specified, set the relevant flags. */
743 MEM_VOLATILE_P (slot
) = TYPE_VOLATILE (type
);
744 MEM_SET_IN_STRUCT_P (slot
, (AGGREGATE_TYPE_P (type
)
745 || TREE_CODE (type
) == COMPLEX_TYPE
));
747 MEM_NOTRAP_P (slot
) = 1;
752 /* Allocate a temporary stack slot and record it for possible later
753 reuse. First three arguments are same as in preceding function. */
756 assign_stack_temp (enum machine_mode mode
, HOST_WIDE_INT size
, int keep
)
758 return assign_stack_temp_for_type (mode
, size
, keep
, NULL_TREE
);
761 /* Assign a temporary.
762 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
763 and so that should be used in error messages. In either case, we
764 allocate of the given type.
765 KEEP is as for assign_stack_temp.
766 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
767 it is 0 if a register is OK.
768 DONT_PROMOTE is 1 if we should not promote values in register
772 assign_temp (tree type_or_decl
, int keep
, int memory_required
,
773 int dont_promote ATTRIBUTE_UNUSED
)
776 enum machine_mode mode
;
781 if (DECL_P (type_or_decl
))
782 decl
= type_or_decl
, type
= TREE_TYPE (decl
);
784 decl
= NULL
, type
= type_or_decl
;
786 mode
= TYPE_MODE (type
);
788 unsignedp
= TYPE_UNSIGNED (type
);
791 if (mode
== BLKmode
|| memory_required
)
793 HOST_WIDE_INT size
= int_size_in_bytes (type
);
796 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
797 problems with allocating the stack space. */
801 /* Unfortunately, we don't yet know how to allocate variable-sized
802 temporaries. However, sometimes we can find a fixed upper limit on
803 the size, so try that instead. */
805 size
= max_int_size_in_bytes (type
);
807 /* The size of the temporary may be too large to fit into an integer. */
808 /* ??? Not sure this should happen except for user silliness, so limit
809 this to things that aren't compiler-generated temporaries. The
810 rest of the time we'll die in assign_stack_temp_for_type. */
811 if (decl
&& size
== -1
812 && TREE_CODE (TYPE_SIZE_UNIT (type
)) == INTEGER_CST
)
814 error ("size of variable %q+D is too large", decl
);
818 tmp
= assign_stack_temp_for_type (mode
, size
, keep
, type
);
824 mode
= promote_mode (type
, mode
, &unsignedp
, 0);
827 return gen_reg_rtx (mode
);
830 /* Combine temporary stack slots which are adjacent on the stack.
832 This allows for better use of already allocated stack space. This is only
833 done for BLKmode slots because we can be sure that we won't have alignment
834 problems in this case. */
837 combine_temp_slots (void)
839 struct temp_slot
*p
, *q
, *next
, *next_q
;
842 /* We can't combine slots, because the information about which slot
843 is in which alias set will be lost. */
844 if (flag_strict_aliasing
)
847 /* If there are a lot of temp slots, don't do anything unless
848 high levels of optimization. */
849 if (! flag_expensive_optimizations
)
850 for (p
= avail_temp_slots
, num_slots
= 0; p
; p
= p
->next
, num_slots
++)
851 if (num_slots
> 100 || (num_slots
> 10 && optimize
== 0))
854 for (p
= avail_temp_slots
; p
; p
= next
)
860 if (GET_MODE (p
->slot
) != BLKmode
)
863 for (q
= p
->next
; q
; q
= next_q
)
869 if (GET_MODE (q
->slot
) != BLKmode
)
872 if (p
->base_offset
+ p
->full_size
== q
->base_offset
)
874 /* Q comes after P; combine Q into P. */
876 p
->full_size
+= q
->full_size
;
879 else if (q
->base_offset
+ q
->full_size
== p
->base_offset
)
881 /* P comes after Q; combine P into Q. */
883 q
->full_size
+= p
->full_size
;
888 cut_slot_from_list (q
, &avail_temp_slots
);
891 /* Either delete P or advance past it. */
893 cut_slot_from_list (p
, &avail_temp_slots
);
897 /* Find the temp slot corresponding to the object at address X. */
899 static struct temp_slot
*
900 find_temp_slot_from_address (rtx x
)
906 for (i
= max_slot_level (); i
>= 0; i
--)
907 for (p
= *temp_slots_at_level (i
); p
; p
= p
->next
)
909 if (XEXP (p
->slot
, 0) == x
911 || (GET_CODE (x
) == PLUS
912 && XEXP (x
, 0) == virtual_stack_vars_rtx
913 && GET_CODE (XEXP (x
, 1)) == CONST_INT
914 && INTVAL (XEXP (x
, 1)) >= p
->base_offset
915 && INTVAL (XEXP (x
, 1)) < p
->base_offset
+ p
->full_size
))
918 else if (p
->address
!= 0 && GET_CODE (p
->address
) == EXPR_LIST
)
919 for (next
= p
->address
; next
; next
= XEXP (next
, 1))
920 if (XEXP (next
, 0) == x
)
924 /* If we have a sum involving a register, see if it points to a temp
926 if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 0))
927 && (p
= find_temp_slot_from_address (XEXP (x
, 0))) != 0)
929 else if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 1))
930 && (p
= find_temp_slot_from_address (XEXP (x
, 1))) != 0)
936 /* Indicate that NEW_RTX is an alternate way of referring to the temp
937 slot that previously was known by OLD_RTX. */
940 update_temp_slot_address (rtx old_rtx
, rtx new_rtx
)
944 if (rtx_equal_p (old_rtx
, new_rtx
))
947 p
= find_temp_slot_from_address (old_rtx
);
949 /* If we didn't find one, see if both OLD_RTX is a PLUS. If so, and
950 NEW_RTX is a register, see if one operand of the PLUS is a
951 temporary location. If so, NEW_RTX points into it. Otherwise,
952 if both OLD_RTX and NEW_RTX are a PLUS and if there is a register
953 in common between them. If so, try a recursive call on those
957 if (GET_CODE (old_rtx
) != PLUS
)
962 update_temp_slot_address (XEXP (old_rtx
, 0), new_rtx
);
963 update_temp_slot_address (XEXP (old_rtx
, 1), new_rtx
);
966 else if (GET_CODE (new_rtx
) != PLUS
)
969 if (rtx_equal_p (XEXP (old_rtx
, 0), XEXP (new_rtx
, 0)))
970 update_temp_slot_address (XEXP (old_rtx
, 1), XEXP (new_rtx
, 1));
971 else if (rtx_equal_p (XEXP (old_rtx
, 1), XEXP (new_rtx
, 0)))
972 update_temp_slot_address (XEXP (old_rtx
, 0), XEXP (new_rtx
, 1));
973 else if (rtx_equal_p (XEXP (old_rtx
, 0), XEXP (new_rtx
, 1)))
974 update_temp_slot_address (XEXP (old_rtx
, 1), XEXP (new_rtx
, 0));
975 else if (rtx_equal_p (XEXP (old_rtx
, 1), XEXP (new_rtx
, 1)))
976 update_temp_slot_address (XEXP (old_rtx
, 0), XEXP (new_rtx
, 0));
981 /* Otherwise add an alias for the temp's address. */
982 else if (p
->address
== 0)
983 p
->address
= new_rtx
;
986 if (GET_CODE (p
->address
) != EXPR_LIST
)
987 p
->address
= gen_rtx_EXPR_LIST (VOIDmode
, p
->address
, NULL_RTX
);
989 p
->address
= gen_rtx_EXPR_LIST (VOIDmode
, new_rtx
, p
->address
);
993 /* If X could be a reference to a temporary slot, mark the fact that its
994 address was taken. */
997 mark_temp_addr_taken (rtx x
)
1004 /* If X is not in memory or is at a constant address, it cannot be in
1005 a temporary slot. */
1006 if (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0)))
1009 p
= find_temp_slot_from_address (XEXP (x
, 0));
1014 /* If X could be a reference to a temporary slot, mark that slot as
1015 belonging to the to one level higher than the current level. If X
1016 matched one of our slots, just mark that one. Otherwise, we can't
1017 easily predict which it is, so upgrade all of them. Kept slots
1018 need not be touched.
1020 This is called when an ({...}) construct occurs and a statement
1021 returns a value in memory. */
1024 preserve_temp_slots (rtx x
)
1026 struct temp_slot
*p
= 0, *next
;
1028 /* If there is no result, we still might have some objects whose address
1029 were taken, so we need to make sure they stay around. */
1032 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1037 move_slot_to_level (p
, temp_slot_level
- 1);
1043 /* If X is a register that is being used as a pointer, see if we have
1044 a temporary slot we know it points to. To be consistent with
1045 the code below, we really should preserve all non-kept slots
1046 if we can't find a match, but that seems to be much too costly. */
1047 if (REG_P (x
) && REG_POINTER (x
))
1048 p
= find_temp_slot_from_address (x
);
1050 /* If X is not in memory or is at a constant address, it cannot be in
1051 a temporary slot, but it can contain something whose address was
1053 if (p
== 0 && (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0))))
1055 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1060 move_slot_to_level (p
, temp_slot_level
- 1);
1066 /* First see if we can find a match. */
1068 p
= find_temp_slot_from_address (XEXP (x
, 0));
1072 /* Move everything at our level whose address was taken to our new
1073 level in case we used its address. */
1074 struct temp_slot
*q
;
1076 if (p
->level
== temp_slot_level
)
1078 for (q
= *temp_slots_at_level (temp_slot_level
); q
; q
= next
)
1082 if (p
!= q
&& q
->addr_taken
)
1083 move_slot_to_level (q
, temp_slot_level
- 1);
1086 move_slot_to_level (p
, temp_slot_level
- 1);
1092 /* Otherwise, preserve all non-kept slots at this level. */
1093 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1098 move_slot_to_level (p
, temp_slot_level
- 1);
1102 /* Free all temporaries used so far. This is normally called at the
1103 end of generating code for a statement. */
1106 free_temp_slots (void)
1108 struct temp_slot
*p
, *next
;
1110 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1115 make_slot_available (p
);
1118 combine_temp_slots ();
1121 /* Push deeper into the nesting level for stack temporaries. */
1124 push_temp_slots (void)
1129 /* Pop a temporary nesting level. All slots in use in the current level
1133 pop_temp_slots (void)
1135 struct temp_slot
*p
, *next
;
1137 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1140 make_slot_available (p
);
1143 combine_temp_slots ();
1148 /* Initialize temporary slots. */
1151 init_temp_slots (void)
1153 /* We have not allocated any temporaries yet. */
1154 avail_temp_slots
= 0;
1155 used_temp_slots
= 0;
1156 temp_slot_level
= 0;
1159 /* These routines are responsible for converting virtual register references
1160 to the actual hard register references once RTL generation is complete.
1162 The following four variables are used for communication between the
1163 routines. They contain the offsets of the virtual registers from their
1164 respective hard registers. */
1166 static int in_arg_offset
;
1167 static int var_offset
;
1168 static int dynamic_offset
;
1169 static int out_arg_offset
;
1170 static int cfa_offset
;
1172 /* In most machines, the stack pointer register is equivalent to the bottom
1175 #ifndef STACK_POINTER_OFFSET
1176 #define STACK_POINTER_OFFSET 0
1179 /* If not defined, pick an appropriate default for the offset of dynamically
1180 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1181 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1183 #ifndef STACK_DYNAMIC_OFFSET
1185 /* The bottom of the stack points to the actual arguments. If
1186 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1187 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1188 stack space for register parameters is not pushed by the caller, but
1189 rather part of the fixed stack areas and hence not included in
1190 `crtl->outgoing_args_size'. Nevertheless, we must allow
1191 for it when allocating stack dynamic objects. */
1193 #if defined(REG_PARM_STACK_SPACE)
1194 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1195 ((ACCUMULATE_OUTGOING_ARGS \
1196 ? (crtl->outgoing_args_size \
1197 + (OUTGOING_REG_PARM_STACK_SPACE ((!(FNDECL) ? NULL_TREE : TREE_TYPE (FNDECL))) ? 0 \
1198 : REG_PARM_STACK_SPACE (FNDECL))) \
1199 : 0) + (STACK_POINTER_OFFSET))
1201 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1202 ((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : 0) \
1203 + (STACK_POINTER_OFFSET))
1208 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1209 is a virtual register, return the equivalent hard register and set the
1210 offset indirectly through the pointer. Otherwise, return 0. */
1213 instantiate_new_reg (rtx x
, HOST_WIDE_INT
*poffset
)
1216 HOST_WIDE_INT offset
;
1218 if (x
== virtual_incoming_args_rtx
)
1220 if (stack_realign_drap
)
1222 /* Replace virtual_incoming_args_rtx with internal arg
1223 pointer if DRAP is used to realign stack. */
1224 new_rtx
= crtl
->args
.internal_arg_pointer
;
1228 new_rtx
= arg_pointer_rtx
, offset
= in_arg_offset
;
1230 else if (x
== virtual_stack_vars_rtx
)
1231 new_rtx
= frame_pointer_rtx
, offset
= var_offset
;
1232 else if (x
== virtual_stack_dynamic_rtx
)
1233 new_rtx
= stack_pointer_rtx
, offset
= dynamic_offset
;
1234 else if (x
== virtual_outgoing_args_rtx
)
1235 new_rtx
= stack_pointer_rtx
, offset
= out_arg_offset
;
1236 else if (x
== virtual_cfa_rtx
)
1238 #ifdef FRAME_POINTER_CFA_OFFSET
1239 new_rtx
= frame_pointer_rtx
;
1241 new_rtx
= arg_pointer_rtx
;
1243 offset
= cfa_offset
;
1252 /* A subroutine of instantiate_virtual_regs, called via for_each_rtx.
1253 Instantiate any virtual registers present inside of *LOC. The expression
1254 is simplified, as much as possible, but is not to be considered "valid"
1255 in any sense implied by the target. If any change is made, set CHANGED
1259 instantiate_virtual_regs_in_rtx (rtx
*loc
, void *data
)
1261 HOST_WIDE_INT offset
;
1262 bool *changed
= (bool *) data
;
1269 switch (GET_CODE (x
))
1272 new_rtx
= instantiate_new_reg (x
, &offset
);
1275 *loc
= plus_constant (new_rtx
, offset
);
1282 new_rtx
= instantiate_new_reg (XEXP (x
, 0), &offset
);
1285 new_rtx
= plus_constant (new_rtx
, offset
);
1286 *loc
= simplify_gen_binary (PLUS
, GET_MODE (x
), new_rtx
, XEXP (x
, 1));
1292 /* FIXME -- from old code */
1293 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1294 we can commute the PLUS and SUBREG because pointers into the
1295 frame are well-behaved. */
1305 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1306 matches the predicate for insn CODE operand OPERAND. */
1309 safe_insn_predicate (int code
, int operand
, rtx x
)
1311 const struct insn_operand_data
*op_data
;
1316 op_data
= &insn_data
[code
].operand
[operand
];
1317 if (op_data
->predicate
== NULL
)
1320 return op_data
->predicate (x
, op_data
->mode
);
1323 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1324 registers present inside of insn. The result will be a valid insn. */
1327 instantiate_virtual_regs_in_insn (rtx insn
)
1329 HOST_WIDE_INT offset
;
1331 bool any_change
= false;
1332 rtx set
, new_rtx
, x
, seq
;
1334 /* There are some special cases to be handled first. */
1335 set
= single_set (insn
);
1338 /* We're allowed to assign to a virtual register. This is interpreted
1339 to mean that the underlying register gets assigned the inverse
1340 transformation. This is used, for example, in the handling of
1342 new_rtx
= instantiate_new_reg (SET_DEST (set
), &offset
);
1347 for_each_rtx (&SET_SRC (set
), instantiate_virtual_regs_in_rtx
, NULL
);
1348 x
= simplify_gen_binary (PLUS
, GET_MODE (new_rtx
), SET_SRC (set
),
1350 x
= force_operand (x
, new_rtx
);
1352 emit_move_insn (new_rtx
, x
);
1357 emit_insn_before (seq
, insn
);
1362 /* Handle a straight copy from a virtual register by generating a
1363 new add insn. The difference between this and falling through
1364 to the generic case is avoiding a new pseudo and eliminating a
1365 move insn in the initial rtl stream. */
1366 new_rtx
= instantiate_new_reg (SET_SRC (set
), &offset
);
1367 if (new_rtx
&& offset
!= 0
1368 && REG_P (SET_DEST (set
))
1369 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1373 x
= expand_simple_binop (GET_MODE (SET_DEST (set
)), PLUS
,
1374 new_rtx
, GEN_INT (offset
), SET_DEST (set
),
1375 1, OPTAB_LIB_WIDEN
);
1376 if (x
!= SET_DEST (set
))
1377 emit_move_insn (SET_DEST (set
), x
);
1382 emit_insn_before (seq
, insn
);
1387 extract_insn (insn
);
1388 insn_code
= INSN_CODE (insn
);
1390 /* Handle a plus involving a virtual register by determining if the
1391 operands remain valid if they're modified in place. */
1392 if (GET_CODE (SET_SRC (set
)) == PLUS
1393 && recog_data
.n_operands
>= 3
1394 && recog_data
.operand_loc
[1] == &XEXP (SET_SRC (set
), 0)
1395 && recog_data
.operand_loc
[2] == &XEXP (SET_SRC (set
), 1)
1396 && GET_CODE (recog_data
.operand
[2]) == CONST_INT
1397 && (new_rtx
= instantiate_new_reg (recog_data
.operand
[1], &offset
)))
1399 offset
+= INTVAL (recog_data
.operand
[2]);
1401 /* If the sum is zero, then replace with a plain move. */
1403 && REG_P (SET_DEST (set
))
1404 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1407 emit_move_insn (SET_DEST (set
), new_rtx
);
1411 emit_insn_before (seq
, insn
);
1416 x
= gen_int_mode (offset
, recog_data
.operand_mode
[2]);
1418 /* Using validate_change and apply_change_group here leaves
1419 recog_data in an invalid state. Since we know exactly what
1420 we want to check, do those two by hand. */
1421 if (safe_insn_predicate (insn_code
, 1, new_rtx
)
1422 && safe_insn_predicate (insn_code
, 2, x
))
1424 *recog_data
.operand_loc
[1] = recog_data
.operand
[1] = new_rtx
;
1425 *recog_data
.operand_loc
[2] = recog_data
.operand
[2] = x
;
1428 /* Fall through into the regular operand fixup loop in
1429 order to take care of operands other than 1 and 2. */
1435 extract_insn (insn
);
1436 insn_code
= INSN_CODE (insn
);
1439 /* In the general case, we expect virtual registers to appear only in
1440 operands, and then only as either bare registers or inside memories. */
1441 for (i
= 0; i
< recog_data
.n_operands
; ++i
)
1443 x
= recog_data
.operand
[i
];
1444 switch (GET_CODE (x
))
1448 rtx addr
= XEXP (x
, 0);
1449 bool changed
= false;
1451 for_each_rtx (&addr
, instantiate_virtual_regs_in_rtx
, &changed
);
1456 x
= replace_equiv_address (x
, addr
);
1457 /* It may happen that the address with the virtual reg
1458 was valid (e.g. based on the virtual stack reg, which might
1459 be acceptable to the predicates with all offsets), whereas
1460 the address now isn't anymore, for instance when the address
1461 is still offsetted, but the base reg isn't virtual-stack-reg
1462 anymore. Below we would do a force_reg on the whole operand,
1463 but this insn might actually only accept memory. Hence,
1464 before doing that last resort, try to reload the address into
1465 a register, so this operand stays a MEM. */
1466 if (!safe_insn_predicate (insn_code
, i
, x
))
1468 addr
= force_reg (GET_MODE (addr
), addr
);
1469 x
= replace_equiv_address (x
, addr
);
1474 emit_insn_before (seq
, insn
);
1479 new_rtx
= instantiate_new_reg (x
, &offset
);
1480 if (new_rtx
== NULL
)
1488 /* Careful, special mode predicates may have stuff in
1489 insn_data[insn_code].operand[i].mode that isn't useful
1490 to us for computing a new value. */
1491 /* ??? Recognize address_operand and/or "p" constraints
1492 to see if (plus new offset) is a valid before we put
1493 this through expand_simple_binop. */
1494 x
= expand_simple_binop (GET_MODE (x
), PLUS
, new_rtx
,
1495 GEN_INT (offset
), NULL_RTX
,
1496 1, OPTAB_LIB_WIDEN
);
1499 emit_insn_before (seq
, insn
);
1504 new_rtx
= instantiate_new_reg (SUBREG_REG (x
), &offset
);
1505 if (new_rtx
== NULL
)
1510 new_rtx
= expand_simple_binop (GET_MODE (new_rtx
), PLUS
, new_rtx
,
1511 GEN_INT (offset
), NULL_RTX
,
1512 1, OPTAB_LIB_WIDEN
);
1515 emit_insn_before (seq
, insn
);
1517 x
= simplify_gen_subreg (recog_data
.operand_mode
[i
], new_rtx
,
1518 GET_MODE (new_rtx
), SUBREG_BYTE (x
));
1526 /* At this point, X contains the new value for the operand.
1527 Validate the new value vs the insn predicate. Note that
1528 asm insns will have insn_code -1 here. */
1529 if (!safe_insn_predicate (insn_code
, i
, x
))
1532 x
= force_reg (insn_data
[insn_code
].operand
[i
].mode
, x
);
1536 emit_insn_before (seq
, insn
);
1539 *recog_data
.operand_loc
[i
] = recog_data
.operand
[i
] = x
;
1545 /* Propagate operand changes into the duplicates. */
1546 for (i
= 0; i
< recog_data
.n_dups
; ++i
)
1547 *recog_data
.dup_loc
[i
]
1548 = copy_rtx (recog_data
.operand
[(unsigned)recog_data
.dup_num
[i
]]);
1550 /* Force re-recognition of the instruction for validation. */
1551 INSN_CODE (insn
) = -1;
1554 if (asm_noperands (PATTERN (insn
)) >= 0)
1556 if (!check_asm_operands (PATTERN (insn
)))
1558 error_for_asm (insn
, "impossible constraint in %<asm%>");
1564 if (recog_memoized (insn
) < 0)
1565 fatal_insn_not_found (insn
);
1569 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1570 do any instantiation required. */
1573 instantiate_decl_rtl (rtx x
)
1580 /* If this is a CONCAT, recurse for the pieces. */
1581 if (GET_CODE (x
) == CONCAT
)
1583 instantiate_decl_rtl (XEXP (x
, 0));
1584 instantiate_decl_rtl (XEXP (x
, 1));
1588 /* If this is not a MEM, no need to do anything. Similarly if the
1589 address is a constant or a register that is not a virtual register. */
1594 if (CONSTANT_P (addr
)
1596 && (REGNO (addr
) < FIRST_VIRTUAL_REGISTER
1597 || REGNO (addr
) > LAST_VIRTUAL_REGISTER
)))
1600 for_each_rtx (&XEXP (x
, 0), instantiate_virtual_regs_in_rtx
, NULL
);
1603 /* Helper for instantiate_decls called via walk_tree: Process all decls
1604 in the given DECL_VALUE_EXPR. */
1607 instantiate_expr (tree
*tp
, int *walk_subtrees
, void *data ATTRIBUTE_UNUSED
)
1613 if (DECL_P (t
) && DECL_RTL_SET_P (t
))
1614 instantiate_decl_rtl (DECL_RTL (t
));
1619 /* Subroutine of instantiate_decls: Process all decls in the given
1620 BLOCK node and all its subblocks. */
1623 instantiate_decls_1 (tree let
)
1627 for (t
= BLOCK_VARS (let
); t
; t
= TREE_CHAIN (t
))
1629 if (DECL_RTL_SET_P (t
))
1630 instantiate_decl_rtl (DECL_RTL (t
));
1631 if (TREE_CODE (t
) == VAR_DECL
&& DECL_HAS_VALUE_EXPR_P (t
))
1633 tree v
= DECL_VALUE_EXPR (t
);
1634 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1638 /* Process all subblocks. */
1639 for (t
= BLOCK_SUBBLOCKS (let
); t
; t
= BLOCK_CHAIN (t
))
1640 instantiate_decls_1 (t
);
1643 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1644 all virtual registers in their DECL_RTL's. */
1647 instantiate_decls (tree fndecl
)
1651 /* Process all parameters of the function. */
1652 for (decl
= DECL_ARGUMENTS (fndecl
); decl
; decl
= TREE_CHAIN (decl
))
1654 instantiate_decl_rtl (DECL_RTL (decl
));
1655 instantiate_decl_rtl (DECL_INCOMING_RTL (decl
));
1656 if (DECL_HAS_VALUE_EXPR_P (decl
))
1658 tree v
= DECL_VALUE_EXPR (decl
);
1659 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1663 /* Now process all variables defined in the function or its subblocks. */
1664 instantiate_decls_1 (DECL_INITIAL (fndecl
));
1667 /* Pass through the INSNS of function FNDECL and convert virtual register
1668 references to hard register references. */
1671 instantiate_virtual_regs (void)
1675 /* Compute the offsets to use for this function. */
1676 in_arg_offset
= FIRST_PARM_OFFSET (current_function_decl
);
1677 var_offset
= STARTING_FRAME_OFFSET
;
1678 dynamic_offset
= STACK_DYNAMIC_OFFSET (current_function_decl
);
1679 out_arg_offset
= STACK_POINTER_OFFSET
;
1680 #ifdef FRAME_POINTER_CFA_OFFSET
1681 cfa_offset
= FRAME_POINTER_CFA_OFFSET (current_function_decl
);
1683 cfa_offset
= ARG_POINTER_CFA_OFFSET (current_function_decl
);
1686 /* Initialize recognition, indicating that volatile is OK. */
1689 /* Scan through all the insns, instantiating every virtual register still
1691 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
1694 /* These patterns in the instruction stream can never be recognized.
1695 Fortunately, they shouldn't contain virtual registers either. */
1696 if (GET_CODE (PATTERN (insn
)) == USE
1697 || GET_CODE (PATTERN (insn
)) == CLOBBER
1698 || GET_CODE (PATTERN (insn
)) == ADDR_VEC
1699 || GET_CODE (PATTERN (insn
)) == ADDR_DIFF_VEC
1700 || GET_CODE (PATTERN (insn
)) == ASM_INPUT
)
1703 instantiate_virtual_regs_in_insn (insn
);
1705 if (INSN_DELETED_P (insn
))
1708 for_each_rtx (®_NOTES (insn
), instantiate_virtual_regs_in_rtx
, NULL
);
1710 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1711 if (GET_CODE (insn
) == CALL_INSN
)
1712 for_each_rtx (&CALL_INSN_FUNCTION_USAGE (insn
),
1713 instantiate_virtual_regs_in_rtx
, NULL
);
1716 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1717 instantiate_decls (current_function_decl
);
1719 targetm
.instantiate_decls ();
1721 /* Indicate that, from now on, assign_stack_local should use
1722 frame_pointer_rtx. */
1723 virtuals_instantiated
= 1;
1727 struct rtl_opt_pass pass_instantiate_virtual_regs
=
1733 instantiate_virtual_regs
, /* execute */
1736 0, /* static_pass_number */
1738 0, /* properties_required */
1739 0, /* properties_provided */
1740 0, /* properties_destroyed */
1741 0, /* todo_flags_start */
1742 TODO_dump_func
/* todo_flags_finish */
1747 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
1748 This means a type for which function calls must pass an address to the
1749 function or get an address back from the function.
1750 EXP may be a type node or an expression (whose type is tested). */
1753 aggregate_value_p (const_tree exp
, const_tree fntype
)
1755 int i
, regno
, nregs
;
1758 const_tree type
= (TYPE_P (exp
)) ? exp
: TREE_TYPE (exp
);
1760 /* DECL node associated with FNTYPE when relevant, which we might need to
1761 check for by-invisible-reference returns, typically for CALL_EXPR input
1763 const_tree fndecl
= NULL_TREE
;
1766 switch (TREE_CODE (fntype
))
1769 fndecl
= get_callee_fndecl (fntype
);
1770 fntype
= fndecl
? TREE_TYPE (fndecl
) : 0;
1774 fntype
= TREE_TYPE (fndecl
);
1779 case IDENTIFIER_NODE
:
1783 /* We don't expect other rtl types here. */
1787 if (TREE_CODE (type
) == VOID_TYPE
)
1790 /* If the front end has decided that this needs to be passed by
1791 reference, do so. */
1792 if ((TREE_CODE (exp
) == PARM_DECL
|| TREE_CODE (exp
) == RESULT_DECL
)
1793 && DECL_BY_REFERENCE (exp
))
1796 /* If the EXPression is a CALL_EXPR, honor DECL_BY_REFERENCE set on the
1797 called function RESULT_DECL, meaning the function returns in memory by
1798 invisible reference. This check lets front-ends not set TREE_ADDRESSABLE
1799 on the function type, which used to be the way to request such a return
1800 mechanism but might now be causing troubles at gimplification time if
1801 temporaries with the function type need to be created. */
1802 if (TREE_CODE (exp
) == CALL_EXPR
&& fndecl
&& DECL_RESULT (fndecl
)
1803 && DECL_BY_REFERENCE (DECL_RESULT (fndecl
)))
1806 if (targetm
.calls
.return_in_memory (type
, fntype
))
1808 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
1809 and thus can't be returned in registers. */
1810 if (TREE_ADDRESSABLE (type
))
1812 if (flag_pcc_struct_return
&& AGGREGATE_TYPE_P (type
))
1814 /* Make sure we have suitable call-clobbered regs to return
1815 the value in; if not, we must return it in memory. */
1816 reg
= hard_function_value (type
, 0, fntype
, 0);
1818 /* If we have something other than a REG (e.g. a PARALLEL), then assume
1823 regno
= REGNO (reg
);
1824 nregs
= hard_regno_nregs
[regno
][TYPE_MODE (type
)];
1825 for (i
= 0; i
< nregs
; i
++)
1826 if (! call_used_regs
[regno
+ i
])
1831 /* Return true if we should assign DECL a pseudo register; false if it
1832 should live on the local stack. */
1835 use_register_for_decl (const_tree decl
)
1837 if (!targetm
.calls
.allocate_stack_slots_for_args())
1840 /* Honor volatile. */
1841 if (TREE_SIDE_EFFECTS (decl
))
1844 /* Honor addressability. */
1845 if (TREE_ADDRESSABLE (decl
))
1848 /* Only register-like things go in registers. */
1849 if (DECL_MODE (decl
) == BLKmode
)
1852 /* If -ffloat-store specified, don't put explicit float variables
1854 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
1855 propagates values across these stores, and it probably shouldn't. */
1856 if (flag_float_store
&& FLOAT_TYPE_P (TREE_TYPE (decl
)))
1859 /* If we're not interested in tracking debugging information for
1860 this decl, then we can certainly put it in a register. */
1861 if (DECL_IGNORED_P (decl
))
1864 return (optimize
|| DECL_REGISTER (decl
));
1867 /* Return true if TYPE should be passed by invisible reference. */
1870 pass_by_reference (CUMULATIVE_ARGS
*ca
, enum machine_mode mode
,
1871 tree type
, bool named_arg
)
1875 /* If this type contains non-trivial constructors, then it is
1876 forbidden for the middle-end to create any new copies. */
1877 if (TREE_ADDRESSABLE (type
))
1880 /* GCC post 3.4 passes *all* variable sized types by reference. */
1881 if (!TYPE_SIZE (type
) || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
1885 return targetm
.calls
.pass_by_reference (ca
, mode
, type
, named_arg
);
1888 /* Return true if TYPE, which is passed by reference, should be callee
1889 copied instead of caller copied. */
1892 reference_callee_copied (CUMULATIVE_ARGS
*ca
, enum machine_mode mode
,
1893 tree type
, bool named_arg
)
1895 if (type
&& TREE_ADDRESSABLE (type
))
1897 return targetm
.calls
.callee_copies (ca
, mode
, type
, named_arg
);
1900 /* Structures to communicate between the subroutines of assign_parms.
1901 The first holds data persistent across all parameters, the second
1902 is cleared out for each parameter. */
1904 struct assign_parm_data_all
1906 CUMULATIVE_ARGS args_so_far
;
1907 struct args_size stack_args_size
;
1908 tree function_result_decl
;
1910 rtx first_conversion_insn
;
1911 rtx last_conversion_insn
;
1912 HOST_WIDE_INT pretend_args_size
;
1913 HOST_WIDE_INT extra_pretend_bytes
;
1914 int reg_parm_stack_space
;
1917 struct assign_parm_data_one
1923 enum machine_mode nominal_mode
;
1924 enum machine_mode passed_mode
;
1925 enum machine_mode promoted_mode
;
1926 struct locate_and_pad_arg_data locate
;
1928 BOOL_BITFIELD named_arg
: 1;
1929 BOOL_BITFIELD passed_pointer
: 1;
1930 BOOL_BITFIELD on_stack
: 1;
1931 BOOL_BITFIELD loaded_in_reg
: 1;
1934 /* A subroutine of assign_parms. Initialize ALL. */
1937 assign_parms_initialize_all (struct assign_parm_data_all
*all
)
1941 memset (all
, 0, sizeof (*all
));
1943 fntype
= TREE_TYPE (current_function_decl
);
1945 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
1946 INIT_CUMULATIVE_INCOMING_ARGS (all
->args_so_far
, fntype
, NULL_RTX
);
1948 INIT_CUMULATIVE_ARGS (all
->args_so_far
, fntype
, NULL_RTX
,
1949 current_function_decl
, -1);
1952 #ifdef REG_PARM_STACK_SPACE
1953 all
->reg_parm_stack_space
= REG_PARM_STACK_SPACE (current_function_decl
);
1957 /* If ARGS contains entries with complex types, split the entry into two
1958 entries of the component type. Return a new list of substitutions are
1959 needed, else the old list. */
1962 split_complex_args (tree args
)
1966 /* Before allocating memory, check for the common case of no complex. */
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
))
1977 args
= copy_list (args
);
1979 for (p
= args
; p
; p
= TREE_CHAIN (p
))
1981 tree type
= TREE_TYPE (p
);
1982 if (TREE_CODE (type
) == COMPLEX_TYPE
1983 && targetm
.calls
.split_complex_arg (type
))
1986 tree subtype
= TREE_TYPE (type
);
1987 bool addressable
= TREE_ADDRESSABLE (p
);
1989 /* Rewrite the PARM_DECL's type with its component. */
1990 TREE_TYPE (p
) = subtype
;
1991 DECL_ARG_TYPE (p
) = TREE_TYPE (DECL_ARG_TYPE (p
));
1992 DECL_MODE (p
) = VOIDmode
;
1993 DECL_SIZE (p
) = NULL
;
1994 DECL_SIZE_UNIT (p
) = NULL
;
1995 /* If this arg must go in memory, put it in a pseudo here.
1996 We can't allow it to go in memory as per normal parms,
1997 because the usual place might not have the imag part
1998 adjacent to the real part. */
1999 DECL_ARTIFICIAL (p
) = addressable
;
2000 DECL_IGNORED_P (p
) = addressable
;
2001 TREE_ADDRESSABLE (p
) = 0;
2004 /* Build a second synthetic decl. */
2005 decl
= build_decl (PARM_DECL
, NULL_TREE
, subtype
);
2006 DECL_ARG_TYPE (decl
) = DECL_ARG_TYPE (p
);
2007 DECL_ARTIFICIAL (decl
) = addressable
;
2008 DECL_IGNORED_P (decl
) = addressable
;
2009 layout_decl (decl
, 0);
2011 /* Splice it in; skip the new decl. */
2012 TREE_CHAIN (decl
) = TREE_CHAIN (p
);
2013 TREE_CHAIN (p
) = decl
;
2021 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
2022 the hidden struct return argument, and (abi willing) complex args.
2023 Return the new parameter list. */
2026 assign_parms_augmented_arg_list (struct assign_parm_data_all
*all
)
2028 tree fndecl
= current_function_decl
;
2029 tree fntype
= TREE_TYPE (fndecl
);
2030 tree fnargs
= DECL_ARGUMENTS (fndecl
);
2032 /* If struct value address is treated as the first argument, make it so. */
2033 if (aggregate_value_p (DECL_RESULT (fndecl
), fndecl
)
2034 && ! cfun
->returns_pcc_struct
2035 && targetm
.calls
.struct_value_rtx (TREE_TYPE (fndecl
), 1) == 0)
2037 tree type
= build_pointer_type (TREE_TYPE (fntype
));
2040 decl
= build_decl (PARM_DECL
, NULL_TREE
, type
);
2041 DECL_ARG_TYPE (decl
) = type
;
2042 DECL_ARTIFICIAL (decl
) = 1;
2043 DECL_IGNORED_P (decl
) = 1;
2045 TREE_CHAIN (decl
) = fnargs
;
2047 all
->function_result_decl
= decl
;
2050 all
->orig_fnargs
= fnargs
;
2052 /* If the target wants to split complex arguments into scalars, do so. */
2053 if (targetm
.calls
.split_complex_arg
)
2054 fnargs
= split_complex_args (fnargs
);
2059 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2060 data for the parameter. Incorporate ABI specifics such as pass-by-
2061 reference and type promotion. */
2064 assign_parm_find_data_types (struct assign_parm_data_all
*all
, tree parm
,
2065 struct assign_parm_data_one
*data
)
2067 tree nominal_type
, passed_type
;
2068 enum machine_mode nominal_mode
, passed_mode
, promoted_mode
;
2070 memset (data
, 0, sizeof (*data
));
2072 /* NAMED_ARG is a misnomer. We really mean 'non-variadic'. */
2074 data
->named_arg
= 1; /* No variadic parms. */
2075 else if (TREE_CHAIN (parm
))
2076 data
->named_arg
= 1; /* Not the last non-variadic parm. */
2077 else if (targetm
.calls
.strict_argument_naming (&all
->args_so_far
))
2078 data
->named_arg
= 1; /* Only variadic ones are unnamed. */
2080 data
->named_arg
= 0; /* Treat as variadic. */
2082 nominal_type
= TREE_TYPE (parm
);
2083 passed_type
= DECL_ARG_TYPE (parm
);
2085 /* Look out for errors propagating this far. Also, if the parameter's
2086 type is void then its value doesn't matter. */
2087 if (TREE_TYPE (parm
) == error_mark_node
2088 /* This can happen after weird syntax errors
2089 or if an enum type is defined among the parms. */
2090 || TREE_CODE (parm
) != PARM_DECL
2091 || passed_type
== NULL
2092 || VOID_TYPE_P (nominal_type
))
2094 nominal_type
= passed_type
= void_type_node
;
2095 nominal_mode
= passed_mode
= promoted_mode
= VOIDmode
;
2099 /* Find mode of arg as it is passed, and mode of arg as it should be
2100 during execution of this function. */
2101 passed_mode
= TYPE_MODE (passed_type
);
2102 nominal_mode
= TYPE_MODE (nominal_type
);
2104 /* If the parm is to be passed as a transparent union, use the type of
2105 the first field for the tests below. We have already verified that
2106 the modes are the same. */
2107 if (TREE_CODE (passed_type
) == UNION_TYPE
2108 && TYPE_TRANSPARENT_UNION (passed_type
))
2109 passed_type
= TREE_TYPE (TYPE_FIELDS (passed_type
));
2111 /* See if this arg was passed by invisible reference. */
2112 if (pass_by_reference (&all
->args_so_far
, passed_mode
,
2113 passed_type
, data
->named_arg
))
2115 passed_type
= nominal_type
= build_pointer_type (passed_type
);
2116 data
->passed_pointer
= true;
2117 passed_mode
= nominal_mode
= Pmode
;
2120 /* Find mode as it is passed by the ABI. */
2121 promoted_mode
= passed_mode
;
2122 if (targetm
.calls
.promote_function_args (TREE_TYPE (current_function_decl
)))
2124 int unsignedp
= TYPE_UNSIGNED (passed_type
);
2125 promoted_mode
= promote_mode (passed_type
, promoted_mode
,
2130 data
->nominal_type
= nominal_type
;
2131 data
->passed_type
= passed_type
;
2132 data
->nominal_mode
= nominal_mode
;
2133 data
->passed_mode
= passed_mode
;
2134 data
->promoted_mode
= promoted_mode
;
2137 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2140 assign_parms_setup_varargs (struct assign_parm_data_all
*all
,
2141 struct assign_parm_data_one
*data
, bool no_rtl
)
2143 int varargs_pretend_bytes
= 0;
2145 targetm
.calls
.setup_incoming_varargs (&all
->args_so_far
,
2146 data
->promoted_mode
,
2148 &varargs_pretend_bytes
, no_rtl
);
2150 /* If the back-end has requested extra stack space, record how much is
2151 needed. Do not change pretend_args_size otherwise since it may be
2152 nonzero from an earlier partial argument. */
2153 if (varargs_pretend_bytes
> 0)
2154 all
->pretend_args_size
= varargs_pretend_bytes
;
2157 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2158 the incoming location of the current parameter. */
2161 assign_parm_find_entry_rtl (struct assign_parm_data_all
*all
,
2162 struct assign_parm_data_one
*data
)
2164 HOST_WIDE_INT pretend_bytes
= 0;
2168 if (data
->promoted_mode
== VOIDmode
)
2170 data
->entry_parm
= data
->stack_parm
= const0_rtx
;
2174 #ifdef FUNCTION_INCOMING_ARG
2175 entry_parm
= FUNCTION_INCOMING_ARG (all
->args_so_far
, data
->promoted_mode
,
2176 data
->passed_type
, data
->named_arg
);
2178 entry_parm
= FUNCTION_ARG (all
->args_so_far
, data
->promoted_mode
,
2179 data
->passed_type
, data
->named_arg
);
2182 if (entry_parm
== 0)
2183 data
->promoted_mode
= data
->passed_mode
;
2185 /* Determine parm's home in the stack, in case it arrives in the stack
2186 or we should pretend it did. Compute the stack position and rtx where
2187 the argument arrives and its size.
2189 There is one complexity here: If this was a parameter that would
2190 have been passed in registers, but wasn't only because it is
2191 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2192 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2193 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2194 as it was the previous time. */
2195 in_regs
= entry_parm
!= 0;
2196 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2199 if (!in_regs
&& !data
->named_arg
)
2201 if (targetm
.calls
.pretend_outgoing_varargs_named (&all
->args_so_far
))
2204 #ifdef FUNCTION_INCOMING_ARG
2205 tem
= FUNCTION_INCOMING_ARG (all
->args_so_far
, data
->promoted_mode
,
2206 data
->passed_type
, true);
2208 tem
= FUNCTION_ARG (all
->args_so_far
, data
->promoted_mode
,
2209 data
->passed_type
, true);
2211 in_regs
= tem
!= NULL
;
2215 /* If this parameter was passed both in registers and in the stack, use
2216 the copy on the stack. */
2217 if (targetm
.calls
.must_pass_in_stack (data
->promoted_mode
,
2225 partial
= targetm
.calls
.arg_partial_bytes (&all
->args_so_far
,
2226 data
->promoted_mode
,
2229 data
->partial
= partial
;
2231 /* The caller might already have allocated stack space for the
2232 register parameters. */
2233 if (partial
!= 0 && all
->reg_parm_stack_space
== 0)
2235 /* Part of this argument is passed in registers and part
2236 is passed on the stack. Ask the prologue code to extend
2237 the stack part so that we can recreate the full value.
2239 PRETEND_BYTES is the size of the registers we need to store.
2240 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2241 stack space that the prologue should allocate.
2243 Internally, gcc assumes that the argument pointer is aligned
2244 to STACK_BOUNDARY bits. This is used both for alignment
2245 optimizations (see init_emit) and to locate arguments that are
2246 aligned to more than PARM_BOUNDARY bits. We must preserve this
2247 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2248 a stack boundary. */
2250 /* We assume at most one partial arg, and it must be the first
2251 argument on the stack. */
2252 gcc_assert (!all
->extra_pretend_bytes
&& !all
->pretend_args_size
);
2254 pretend_bytes
= partial
;
2255 all
->pretend_args_size
= CEIL_ROUND (pretend_bytes
, STACK_BYTES
);
2257 /* We want to align relative to the actual stack pointer, so
2258 don't include this in the stack size until later. */
2259 all
->extra_pretend_bytes
= all
->pretend_args_size
;
2263 locate_and_pad_parm (data
->promoted_mode
, data
->passed_type
, in_regs
,
2264 entry_parm
? data
->partial
: 0, current_function_decl
,
2265 &all
->stack_args_size
, &data
->locate
);
2267 /* Update parm_stack_boundary if this parameter is passed in the
2269 if (!in_regs
&& crtl
->parm_stack_boundary
< data
->locate
.boundary
)
2270 crtl
->parm_stack_boundary
= data
->locate
.boundary
;
2272 /* Adjust offsets to include the pretend args. */
2273 pretend_bytes
= all
->extra_pretend_bytes
- pretend_bytes
;
2274 data
->locate
.slot_offset
.constant
+= pretend_bytes
;
2275 data
->locate
.offset
.constant
+= pretend_bytes
;
2277 data
->entry_parm
= entry_parm
;
2280 /* A subroutine of assign_parms. If there is actually space on the stack
2281 for this parm, count it in stack_args_size and return true. */
2284 assign_parm_is_stack_parm (struct assign_parm_data_all
*all
,
2285 struct assign_parm_data_one
*data
)
2287 /* Trivially true if we've no incoming register. */
2288 if (data
->entry_parm
== NULL
)
2290 /* Also true if we're partially in registers and partially not,
2291 since we've arranged to drop the entire argument on the stack. */
2292 else if (data
->partial
!= 0)
2294 /* Also true if the target says that it's passed in both registers
2295 and on the stack. */
2296 else if (GET_CODE (data
->entry_parm
) == PARALLEL
2297 && XEXP (XVECEXP (data
->entry_parm
, 0, 0), 0) == NULL_RTX
)
2299 /* Also true if the target says that there's stack allocated for
2300 all register parameters. */
2301 else if (all
->reg_parm_stack_space
> 0)
2303 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2307 all
->stack_args_size
.constant
+= data
->locate
.size
.constant
;
2308 if (data
->locate
.size
.var
)
2309 ADD_PARM_SIZE (all
->stack_args_size
, data
->locate
.size
.var
);
2314 /* A subroutine of assign_parms. Given that this parameter is allocated
2315 stack space by the ABI, find it. */
2318 assign_parm_find_stack_rtl (tree parm
, struct assign_parm_data_one
*data
)
2320 rtx offset_rtx
, stack_parm
;
2321 unsigned int align
, boundary
;
2323 /* If we're passing this arg using a reg, make its stack home the
2324 aligned stack slot. */
2325 if (data
->entry_parm
)
2326 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.slot_offset
);
2328 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.offset
);
2330 stack_parm
= crtl
->args
.internal_arg_pointer
;
2331 if (offset_rtx
!= const0_rtx
)
2332 stack_parm
= gen_rtx_PLUS (Pmode
, stack_parm
, offset_rtx
);
2333 stack_parm
= gen_rtx_MEM (data
->promoted_mode
, stack_parm
);
2335 set_mem_attributes (stack_parm
, parm
, 1);
2336 /* set_mem_attributes could set MEM_SIZE to the passed mode's size,
2337 while promoted mode's size is needed. */
2338 if (data
->promoted_mode
!= BLKmode
2339 && data
->promoted_mode
!= DECL_MODE (parm
))
2340 set_mem_size (stack_parm
, GEN_INT (GET_MODE_SIZE (data
->promoted_mode
)));
2342 boundary
= data
->locate
.boundary
;
2343 align
= BITS_PER_UNIT
;
2345 /* If we're padding upward, we know that the alignment of the slot
2346 is FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2347 intentionally forcing upward padding. Otherwise we have to come
2348 up with a guess at the alignment based on OFFSET_RTX. */
2349 if (data
->locate
.where_pad
!= downward
|| data
->entry_parm
)
2351 else if (GET_CODE (offset_rtx
) == CONST_INT
)
2353 align
= INTVAL (offset_rtx
) * BITS_PER_UNIT
| boundary
;
2354 align
= align
& -align
;
2356 set_mem_align (stack_parm
, align
);
2358 if (data
->entry_parm
)
2359 set_reg_attrs_for_parm (data
->entry_parm
, stack_parm
);
2361 data
->stack_parm
= stack_parm
;
2364 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2365 always valid and contiguous. */
2368 assign_parm_adjust_entry_rtl (struct assign_parm_data_one
*data
)
2370 rtx entry_parm
= data
->entry_parm
;
2371 rtx stack_parm
= data
->stack_parm
;
2373 /* If this parm was passed part in regs and part in memory, pretend it
2374 arrived entirely in memory by pushing the register-part onto the stack.
2375 In the special case of a DImode or DFmode that is split, we could put
2376 it together in a pseudoreg directly, but for now that's not worth
2378 if (data
->partial
!= 0)
2380 /* Handle calls that pass values in multiple non-contiguous
2381 locations. The Irix 6 ABI has examples of this. */
2382 if (GET_CODE (entry_parm
) == PARALLEL
)
2383 emit_group_store (validize_mem (stack_parm
), entry_parm
,
2385 int_size_in_bytes (data
->passed_type
));
2388 gcc_assert (data
->partial
% UNITS_PER_WORD
== 0);
2389 move_block_from_reg (REGNO (entry_parm
), validize_mem (stack_parm
),
2390 data
->partial
/ UNITS_PER_WORD
);
2393 entry_parm
= stack_parm
;
2396 /* If we didn't decide this parm came in a register, by default it came
2398 else if (entry_parm
== NULL
)
2399 entry_parm
= stack_parm
;
2401 /* When an argument is passed in multiple locations, we can't make use
2402 of this information, but we can save some copying if the whole argument
2403 is passed in a single register. */
2404 else if (GET_CODE (entry_parm
) == PARALLEL
2405 && data
->nominal_mode
!= BLKmode
2406 && data
->passed_mode
!= BLKmode
)
2408 size_t i
, len
= XVECLEN (entry_parm
, 0);
2410 for (i
= 0; i
< len
; i
++)
2411 if (XEXP (XVECEXP (entry_parm
, 0, i
), 0) != NULL_RTX
2412 && REG_P (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2413 && (GET_MODE (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2414 == data
->passed_mode
)
2415 && INTVAL (XEXP (XVECEXP (entry_parm
, 0, i
), 1)) == 0)
2417 entry_parm
= XEXP (XVECEXP (entry_parm
, 0, i
), 0);
2422 data
->entry_parm
= entry_parm
;
2425 /* A subroutine of assign_parms. Reconstitute any values which were
2426 passed in multiple registers and would fit in a single register. */
2429 assign_parm_remove_parallels (struct assign_parm_data_one
*data
)
2431 rtx entry_parm
= data
->entry_parm
;
2433 /* Convert the PARALLEL to a REG of the same mode as the parallel.
2434 This can be done with register operations rather than on the
2435 stack, even if we will store the reconstituted parameter on the
2437 if (GET_CODE (entry_parm
) == PARALLEL
&& GET_MODE (entry_parm
) != BLKmode
)
2439 rtx parmreg
= gen_reg_rtx (GET_MODE (entry_parm
));
2440 emit_group_store (parmreg
, entry_parm
, NULL_TREE
,
2441 GET_MODE_SIZE (GET_MODE (entry_parm
)));
2442 entry_parm
= parmreg
;
2445 data
->entry_parm
= entry_parm
;
2448 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2449 always valid and properly aligned. */
2452 assign_parm_adjust_stack_rtl (struct assign_parm_data_one
*data
)
2454 rtx stack_parm
= data
->stack_parm
;
2456 /* If we can't trust the parm stack slot to be aligned enough for its
2457 ultimate type, don't use that slot after entry. We'll make another
2458 stack slot, if we need one. */
2460 && ((STRICT_ALIGNMENT
2461 && GET_MODE_ALIGNMENT (data
->nominal_mode
) > MEM_ALIGN (stack_parm
))
2462 || (data
->nominal_type
2463 && TYPE_ALIGN (data
->nominal_type
) > MEM_ALIGN (stack_parm
)
2464 && MEM_ALIGN (stack_parm
) < PREFERRED_STACK_BOUNDARY
)))
2467 /* If parm was passed in memory, and we need to convert it on entry,
2468 don't store it back in that same slot. */
2469 else if (data
->entry_parm
== stack_parm
2470 && data
->nominal_mode
!= BLKmode
2471 && data
->nominal_mode
!= data
->passed_mode
)
2474 /* If stack protection is in effect for this function, don't leave any
2475 pointers in their passed stack slots. */
2476 else if (crtl
->stack_protect_guard
2477 && (flag_stack_protect
== 2
2478 || data
->passed_pointer
2479 || POINTER_TYPE_P (data
->nominal_type
)))
2482 data
->stack_parm
= stack_parm
;
2485 /* A subroutine of assign_parms. Return true if the current parameter
2486 should be stored as a BLKmode in the current frame. */
2489 assign_parm_setup_block_p (struct assign_parm_data_one
*data
)
2491 if (data
->nominal_mode
== BLKmode
)
2493 if (GET_MODE (data
->entry_parm
) == BLKmode
)
2496 #ifdef BLOCK_REG_PADDING
2497 /* Only assign_parm_setup_block knows how to deal with register arguments
2498 that are padded at the least significant end. */
2499 if (REG_P (data
->entry_parm
)
2500 && GET_MODE_SIZE (data
->promoted_mode
) < UNITS_PER_WORD
2501 && (BLOCK_REG_PADDING (data
->passed_mode
, data
->passed_type
, 1)
2502 == (BYTES_BIG_ENDIAN
? upward
: downward
)))
2509 /* A subroutine of assign_parms. Arrange for the parameter to be
2510 present and valid in DATA->STACK_RTL. */
2513 assign_parm_setup_block (struct assign_parm_data_all
*all
,
2514 tree parm
, struct assign_parm_data_one
*data
)
2516 rtx entry_parm
= data
->entry_parm
;
2517 rtx stack_parm
= data
->stack_parm
;
2519 HOST_WIDE_INT size_stored
;
2521 if (GET_CODE (entry_parm
) == PARALLEL
)
2522 entry_parm
= emit_group_move_into_temps (entry_parm
);
2524 size
= int_size_in_bytes (data
->passed_type
);
2525 size_stored
= CEIL_ROUND (size
, UNITS_PER_WORD
);
2526 if (stack_parm
== 0)
2528 DECL_ALIGN (parm
) = MAX (DECL_ALIGN (parm
), BITS_PER_WORD
);
2529 stack_parm
= assign_stack_local (BLKmode
, size_stored
,
2531 if (GET_MODE_SIZE (GET_MODE (entry_parm
)) == size
)
2532 PUT_MODE (stack_parm
, GET_MODE (entry_parm
));
2533 set_mem_attributes (stack_parm
, parm
, 1);
2536 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2537 calls that pass values in multiple non-contiguous locations. */
2538 if (REG_P (entry_parm
) || GET_CODE (entry_parm
) == PARALLEL
)
2542 /* Note that we will be storing an integral number of words.
2543 So we have to be careful to ensure that we allocate an
2544 integral number of words. We do this above when we call
2545 assign_stack_local if space was not allocated in the argument
2546 list. If it was, this will not work if PARM_BOUNDARY is not
2547 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2548 if it becomes a problem. Exception is when BLKmode arrives
2549 with arguments not conforming to word_mode. */
2551 if (data
->stack_parm
== 0)
2553 else if (GET_CODE (entry_parm
) == PARALLEL
)
2556 gcc_assert (!size
|| !(PARM_BOUNDARY
% BITS_PER_WORD
));
2558 mem
= validize_mem (stack_parm
);
2560 /* Handle values in multiple non-contiguous locations. */
2561 if (GET_CODE (entry_parm
) == PARALLEL
)
2563 push_to_sequence2 (all
->first_conversion_insn
,
2564 all
->last_conversion_insn
);
2565 emit_group_store (mem
, entry_parm
, data
->passed_type
, size
);
2566 all
->first_conversion_insn
= get_insns ();
2567 all
->last_conversion_insn
= get_last_insn ();
2574 /* If SIZE is that of a mode no bigger than a word, just use
2575 that mode's store operation. */
2576 else if (size
<= UNITS_PER_WORD
)
2578 enum machine_mode mode
2579 = mode_for_size (size
* BITS_PER_UNIT
, MODE_INT
, 0);
2582 #ifdef BLOCK_REG_PADDING
2583 && (size
== UNITS_PER_WORD
2584 || (BLOCK_REG_PADDING (mode
, data
->passed_type
, 1)
2585 != (BYTES_BIG_ENDIAN
? upward
: downward
)))
2591 /* We are really truncating a word_mode value containing
2592 SIZE bytes into a value of mode MODE. If such an
2593 operation requires no actual instructions, we can refer
2594 to the value directly in mode MODE, otherwise we must
2595 start with the register in word_mode and explicitly
2597 if (TRULY_NOOP_TRUNCATION (size
* BITS_PER_UNIT
, BITS_PER_WORD
))
2598 reg
= gen_rtx_REG (mode
, REGNO (entry_parm
));
2601 reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
2602 reg
= convert_to_mode (mode
, copy_to_reg (reg
), 1);
2604 emit_move_insn (change_address (mem
, mode
, 0), reg
);
2607 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
2608 machine must be aligned to the left before storing
2609 to memory. Note that the previous test doesn't
2610 handle all cases (e.g. SIZE == 3). */
2611 else if (size
!= UNITS_PER_WORD
2612 #ifdef BLOCK_REG_PADDING
2613 && (BLOCK_REG_PADDING (mode
, data
->passed_type
, 1)
2621 int by
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
2622 rtx reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
2624 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
,
2625 build_int_cst (NULL_TREE
, by
),
2627 tem
= change_address (mem
, word_mode
, 0);
2628 emit_move_insn (tem
, x
);
2631 move_block_from_reg (REGNO (entry_parm
), mem
,
2632 size_stored
/ UNITS_PER_WORD
);
2635 move_block_from_reg (REGNO (entry_parm
), mem
,
2636 size_stored
/ UNITS_PER_WORD
);
2638 else if (data
->stack_parm
== 0)
2640 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2641 emit_block_move (stack_parm
, data
->entry_parm
, GEN_INT (size
),
2643 all
->first_conversion_insn
= get_insns ();
2644 all
->last_conversion_insn
= get_last_insn ();
2648 data
->stack_parm
= stack_parm
;
2649 SET_DECL_RTL (parm
, stack_parm
);
2652 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
2653 parameter. Get it there. Perform all ABI specified conversions. */
2656 assign_parm_setup_reg (struct assign_parm_data_all
*all
, tree parm
,
2657 struct assign_parm_data_one
*data
)
2660 enum machine_mode promoted_nominal_mode
;
2661 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (parm
));
2662 bool did_conversion
= false;
2664 /* Store the parm in a pseudoregister during the function, but we may
2665 need to do it in a wider mode. */
2667 /* This is not really promoting for a call. However we need to be
2668 consistent with assign_parm_find_data_types and expand_expr_real_1. */
2669 promoted_nominal_mode
2670 = promote_mode (data
->nominal_type
, data
->nominal_mode
, &unsignedp
, 1);
2672 parmreg
= gen_reg_rtx (promoted_nominal_mode
);
2674 if (!DECL_ARTIFICIAL (parm
))
2675 mark_user_reg (parmreg
);
2677 /* If this was an item that we received a pointer to,
2678 set DECL_RTL appropriately. */
2679 if (data
->passed_pointer
)
2681 rtx x
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data
->passed_type
)), parmreg
);
2682 set_mem_attributes (x
, parm
, 1);
2683 SET_DECL_RTL (parm
, x
);
2686 SET_DECL_RTL (parm
, parmreg
);
2688 assign_parm_remove_parallels (data
);
2690 /* Copy the value into the register. */
2691 if (data
->nominal_mode
!= data
->passed_mode
2692 || promoted_nominal_mode
!= data
->promoted_mode
)
2696 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
2697 mode, by the caller. We now have to convert it to
2698 NOMINAL_MODE, if different. However, PARMREG may be in
2699 a different mode than NOMINAL_MODE if it is being stored
2702 If ENTRY_PARM is a hard register, it might be in a register
2703 not valid for operating in its mode (e.g., an odd-numbered
2704 register for a DFmode). In that case, moves are the only
2705 thing valid, so we can't do a convert from there. This
2706 occurs when the calling sequence allow such misaligned
2709 In addition, the conversion may involve a call, which could
2710 clobber parameters which haven't been copied to pseudo
2711 registers yet. Therefore, we must first copy the parm to
2712 a pseudo reg here, and save the conversion until after all
2713 parameters have been moved. */
2715 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
2717 emit_move_insn (tempreg
, validize_mem (data
->entry_parm
));
2719 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2720 tempreg
= convert_to_mode (data
->nominal_mode
, tempreg
, unsignedp
);
2722 if (GET_CODE (tempreg
) == SUBREG
2723 && GET_MODE (tempreg
) == data
->nominal_mode
2724 && REG_P (SUBREG_REG (tempreg
))
2725 && data
->nominal_mode
== data
->passed_mode
2726 && GET_MODE (SUBREG_REG (tempreg
)) == GET_MODE (data
->entry_parm
)
2727 && GET_MODE_SIZE (GET_MODE (tempreg
))
2728 < GET_MODE_SIZE (GET_MODE (data
->entry_parm
)))
2730 /* The argument is already sign/zero extended, so note it
2732 SUBREG_PROMOTED_VAR_P (tempreg
) = 1;
2733 SUBREG_PROMOTED_UNSIGNED_SET (tempreg
, unsignedp
);
2736 /* TREE_USED gets set erroneously during expand_assignment. */
2737 save_tree_used
= TREE_USED (parm
);
2738 expand_assignment (parm
, make_tree (data
->nominal_type
, tempreg
), false);
2739 TREE_USED (parm
) = save_tree_used
;
2740 all
->first_conversion_insn
= get_insns ();
2741 all
->last_conversion_insn
= get_last_insn ();
2744 did_conversion
= true;
2747 emit_move_insn (parmreg
, validize_mem (data
->entry_parm
));
2749 /* If we were passed a pointer but the actual value can safely live
2750 in a register, put it in one. */
2751 if (data
->passed_pointer
2752 && TYPE_MODE (TREE_TYPE (parm
)) != BLKmode
2753 /* If by-reference argument was promoted, demote it. */
2754 && (TYPE_MODE (TREE_TYPE (parm
)) != GET_MODE (DECL_RTL (parm
))
2755 || use_register_for_decl (parm
)))
2757 /* We can't use nominal_mode, because it will have been set to
2758 Pmode above. We must use the actual mode of the parm. */
2759 parmreg
= gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm
)));
2760 mark_user_reg (parmreg
);
2762 if (GET_MODE (parmreg
) != GET_MODE (DECL_RTL (parm
)))
2764 rtx tempreg
= gen_reg_rtx (GET_MODE (DECL_RTL (parm
)));
2765 int unsigned_p
= TYPE_UNSIGNED (TREE_TYPE (parm
));
2767 push_to_sequence2 (all
->first_conversion_insn
,
2768 all
->last_conversion_insn
);
2769 emit_move_insn (tempreg
, DECL_RTL (parm
));
2770 tempreg
= convert_to_mode (GET_MODE (parmreg
), tempreg
, unsigned_p
);
2771 emit_move_insn (parmreg
, tempreg
);
2772 all
->first_conversion_insn
= get_insns ();
2773 all
->last_conversion_insn
= get_last_insn ();
2776 did_conversion
= true;
2779 emit_move_insn (parmreg
, DECL_RTL (parm
));
2781 SET_DECL_RTL (parm
, parmreg
);
2783 /* STACK_PARM is the pointer, not the parm, and PARMREG is
2785 data
->stack_parm
= NULL
;
2788 /* Mark the register as eliminable if we did no conversion and it was
2789 copied from memory at a fixed offset, and the arg pointer was not
2790 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
2791 offset formed an invalid address, such memory-equivalences as we
2792 make here would screw up life analysis for it. */
2793 if (data
->nominal_mode
== data
->passed_mode
2795 && data
->stack_parm
!= 0
2796 && MEM_P (data
->stack_parm
)
2797 && data
->locate
.offset
.var
== 0
2798 && reg_mentioned_p (virtual_incoming_args_rtx
,
2799 XEXP (data
->stack_parm
, 0)))
2801 rtx linsn
= get_last_insn ();
2804 /* Mark complex types separately. */
2805 if (GET_CODE (parmreg
) == CONCAT
)
2807 enum machine_mode submode
2808 = GET_MODE_INNER (GET_MODE (parmreg
));
2809 int regnor
= REGNO (XEXP (parmreg
, 0));
2810 int regnoi
= REGNO (XEXP (parmreg
, 1));
2811 rtx stackr
= adjust_address_nv (data
->stack_parm
, submode
, 0);
2812 rtx stacki
= adjust_address_nv (data
->stack_parm
, submode
,
2813 GET_MODE_SIZE (submode
));
2815 /* Scan backwards for the set of the real and
2817 for (sinsn
= linsn
; sinsn
!= 0;
2818 sinsn
= prev_nonnote_insn (sinsn
))
2820 set
= single_set (sinsn
);
2824 if (SET_DEST (set
) == regno_reg_rtx
[regnoi
])
2825 set_unique_reg_note (sinsn
, REG_EQUIV
, stacki
);
2826 else if (SET_DEST (set
) == regno_reg_rtx
[regnor
])
2827 set_unique_reg_note (sinsn
, REG_EQUIV
, stackr
);
2830 else if ((set
= single_set (linsn
)) != 0
2831 && SET_DEST (set
) == parmreg
)
2832 set_unique_reg_note (linsn
, REG_EQUIV
, data
->stack_parm
);
2835 /* For pointer data type, suggest pointer register. */
2836 if (POINTER_TYPE_P (TREE_TYPE (parm
)))
2837 mark_reg_pointer (parmreg
,
2838 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
2841 /* A subroutine of assign_parms. Allocate stack space to hold the current
2842 parameter. Get it there. Perform all ABI specified conversions. */
2845 assign_parm_setup_stack (struct assign_parm_data_all
*all
, tree parm
,
2846 struct assign_parm_data_one
*data
)
2848 /* Value must be stored in the stack slot STACK_PARM during function
2850 bool to_conversion
= false;
2852 assign_parm_remove_parallels (data
);
2854 if (data
->promoted_mode
!= data
->nominal_mode
)
2856 /* Conversion is required. */
2857 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
2859 emit_move_insn (tempreg
, validize_mem (data
->entry_parm
));
2861 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2862 to_conversion
= true;
2864 data
->entry_parm
= convert_to_mode (data
->nominal_mode
, tempreg
,
2865 TYPE_UNSIGNED (TREE_TYPE (parm
)));
2867 if (data
->stack_parm
)
2868 /* ??? This may need a big-endian conversion on sparc64. */
2870 = adjust_address (data
->stack_parm
, data
->nominal_mode
, 0);
2873 if (data
->entry_parm
!= data
->stack_parm
)
2877 if (data
->stack_parm
== 0)
2880 = assign_stack_local (GET_MODE (data
->entry_parm
),
2881 GET_MODE_SIZE (GET_MODE (data
->entry_parm
)),
2882 TYPE_ALIGN (data
->passed_type
));
2883 set_mem_attributes (data
->stack_parm
, parm
, 1);
2886 dest
= validize_mem (data
->stack_parm
);
2887 src
= validize_mem (data
->entry_parm
);
2891 /* Use a block move to handle potentially misaligned entry_parm. */
2893 push_to_sequence2 (all
->first_conversion_insn
,
2894 all
->last_conversion_insn
);
2895 to_conversion
= true;
2897 emit_block_move (dest
, src
,
2898 GEN_INT (int_size_in_bytes (data
->passed_type
)),
2902 emit_move_insn (dest
, src
);
2907 all
->first_conversion_insn
= get_insns ();
2908 all
->last_conversion_insn
= get_last_insn ();
2912 SET_DECL_RTL (parm
, data
->stack_parm
);
2915 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
2916 undo the frobbing that we did in assign_parms_augmented_arg_list. */
2919 assign_parms_unsplit_complex (struct assign_parm_data_all
*all
, tree fnargs
)
2922 tree orig_fnargs
= all
->orig_fnargs
;
2924 for (parm
= orig_fnargs
; parm
; parm
= TREE_CHAIN (parm
))
2926 if (TREE_CODE (TREE_TYPE (parm
)) == COMPLEX_TYPE
2927 && targetm
.calls
.split_complex_arg (TREE_TYPE (parm
)))
2929 rtx tmp
, real
, imag
;
2930 enum machine_mode inner
= GET_MODE_INNER (DECL_MODE (parm
));
2932 real
= DECL_RTL (fnargs
);
2933 imag
= DECL_RTL (TREE_CHAIN (fnargs
));
2934 if (inner
!= GET_MODE (real
))
2936 real
= gen_lowpart_SUBREG (inner
, real
);
2937 imag
= gen_lowpart_SUBREG (inner
, imag
);
2940 if (TREE_ADDRESSABLE (parm
))
2943 HOST_WIDE_INT size
= int_size_in_bytes (TREE_TYPE (parm
));
2945 /* split_complex_arg put the real and imag parts in
2946 pseudos. Move them to memory. */
2947 tmp
= assign_stack_local (DECL_MODE (parm
), size
,
2948 TYPE_ALIGN (TREE_TYPE (parm
)));
2949 set_mem_attributes (tmp
, parm
, 1);
2950 rmem
= adjust_address_nv (tmp
, inner
, 0);
2951 imem
= adjust_address_nv (tmp
, inner
, GET_MODE_SIZE (inner
));
2952 push_to_sequence2 (all
->first_conversion_insn
,
2953 all
->last_conversion_insn
);
2954 emit_move_insn (rmem
, real
);
2955 emit_move_insn (imem
, imag
);
2956 all
->first_conversion_insn
= get_insns ();
2957 all
->last_conversion_insn
= get_last_insn ();
2961 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
2962 SET_DECL_RTL (parm
, tmp
);
2964 real
= DECL_INCOMING_RTL (fnargs
);
2965 imag
= DECL_INCOMING_RTL (TREE_CHAIN (fnargs
));
2966 if (inner
!= GET_MODE (real
))
2968 real
= gen_lowpart_SUBREG (inner
, real
);
2969 imag
= gen_lowpart_SUBREG (inner
, imag
);
2971 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
2972 set_decl_incoming_rtl (parm
, tmp
, false);
2973 fnargs
= TREE_CHAIN (fnargs
);
2977 SET_DECL_RTL (parm
, DECL_RTL (fnargs
));
2978 set_decl_incoming_rtl (parm
, DECL_INCOMING_RTL (fnargs
), false);
2980 /* Set MEM_EXPR to the original decl, i.e. to PARM,
2981 instead of the copy of decl, i.e. FNARGS. */
2982 if (DECL_INCOMING_RTL (parm
) && MEM_P (DECL_INCOMING_RTL (parm
)))
2983 set_mem_expr (DECL_INCOMING_RTL (parm
), parm
);
2986 fnargs
= TREE_CHAIN (fnargs
);
2990 /* Assign RTL expressions to the function's parameters. This may involve
2991 copying them into registers and using those registers as the DECL_RTL. */
2994 assign_parms (tree fndecl
)
2996 struct assign_parm_data_all all
;
2999 crtl
->args
.internal_arg_pointer
3000 = targetm
.calls
.internal_arg_pointer ();
3002 assign_parms_initialize_all (&all
);
3003 fnargs
= assign_parms_augmented_arg_list (&all
);
3005 for (parm
= fnargs
; parm
; parm
= TREE_CHAIN (parm
))
3007 struct assign_parm_data_one data
;
3009 /* Extract the type of PARM; adjust it according to ABI. */
3010 assign_parm_find_data_types (&all
, parm
, &data
);
3012 /* Early out for errors and void parameters. */
3013 if (data
.passed_mode
== VOIDmode
)
3015 SET_DECL_RTL (parm
, const0_rtx
);
3016 DECL_INCOMING_RTL (parm
) = DECL_RTL (parm
);
3020 /* Estimate stack alignment from parameter alignment. */
3021 if (SUPPORTS_STACK_ALIGNMENT
)
3023 unsigned int align
= FUNCTION_ARG_BOUNDARY (data
.promoted_mode
,
3025 if (TYPE_ALIGN (data
.nominal_type
) > align
)
3026 align
= TYPE_ALIGN (data
.passed_type
);
3027 if (crtl
->stack_alignment_estimated
< align
)
3029 gcc_assert (!crtl
->stack_realign_processed
);
3030 crtl
->stack_alignment_estimated
= align
;
3034 if (cfun
->stdarg
&& !TREE_CHAIN (parm
))
3035 assign_parms_setup_varargs (&all
, &data
, false);
3037 /* Find out where the parameter arrives in this function. */
3038 assign_parm_find_entry_rtl (&all
, &data
);
3040 /* Find out where stack space for this parameter might be. */
3041 if (assign_parm_is_stack_parm (&all
, &data
))
3043 assign_parm_find_stack_rtl (parm
, &data
);
3044 assign_parm_adjust_entry_rtl (&data
);
3047 /* Record permanently how this parm was passed. */
3048 set_decl_incoming_rtl (parm
, data
.entry_parm
, data
.passed_pointer
);
3050 /* Update info on where next arg arrives in registers. */
3051 FUNCTION_ARG_ADVANCE (all
.args_so_far
, data
.promoted_mode
,
3052 data
.passed_type
, data
.named_arg
);
3054 assign_parm_adjust_stack_rtl (&data
);
3056 if (assign_parm_setup_block_p (&data
))
3057 assign_parm_setup_block (&all
, parm
, &data
);
3058 else if (data
.passed_pointer
|| use_register_for_decl (parm
))
3059 assign_parm_setup_reg (&all
, parm
, &data
);
3061 assign_parm_setup_stack (&all
, parm
, &data
);
3064 if (targetm
.calls
.split_complex_arg
&& fnargs
!= all
.orig_fnargs
)
3065 assign_parms_unsplit_complex (&all
, fnargs
);
3067 /* Output all parameter conversion instructions (possibly including calls)
3068 now that all parameters have been copied out of hard registers. */
3069 emit_insn (all
.first_conversion_insn
);
3071 /* Estimate reload stack alignment from scalar return mode. */
3072 if (SUPPORTS_STACK_ALIGNMENT
)
3074 if (DECL_RESULT (fndecl
))
3076 tree type
= TREE_TYPE (DECL_RESULT (fndecl
));
3077 enum machine_mode mode
= TYPE_MODE (type
);
3081 && !AGGREGATE_TYPE_P (type
))
3083 unsigned int align
= GET_MODE_ALIGNMENT (mode
);
3084 if (crtl
->stack_alignment_estimated
< align
)
3086 gcc_assert (!crtl
->stack_realign_processed
);
3087 crtl
->stack_alignment_estimated
= align
;
3093 /* If we are receiving a struct value address as the first argument, set up
3094 the RTL for the function result. As this might require code to convert
3095 the transmitted address to Pmode, we do this here to ensure that possible
3096 preliminary conversions of the address have been emitted already. */
3097 if (all
.function_result_decl
)
3099 tree result
= DECL_RESULT (current_function_decl
);
3100 rtx addr
= DECL_RTL (all
.function_result_decl
);
3103 if (DECL_BY_REFERENCE (result
))
3107 addr
= convert_memory_address (Pmode
, addr
);
3108 x
= gen_rtx_MEM (DECL_MODE (result
), addr
);
3109 set_mem_attributes (x
, result
, 1);
3111 SET_DECL_RTL (result
, x
);
3114 /* We have aligned all the args, so add space for the pretend args. */
3115 crtl
->args
.pretend_args_size
= all
.pretend_args_size
;
3116 all
.stack_args_size
.constant
+= all
.extra_pretend_bytes
;
3117 crtl
->args
.size
= all
.stack_args_size
.constant
;
3119 /* Adjust function incoming argument size for alignment and
3122 #ifdef REG_PARM_STACK_SPACE
3123 crtl
->args
.size
= MAX (crtl
->args
.size
,
3124 REG_PARM_STACK_SPACE (fndecl
));
3127 crtl
->args
.size
= CEIL_ROUND (crtl
->args
.size
,
3128 PARM_BOUNDARY
/ BITS_PER_UNIT
);
3130 #ifdef ARGS_GROW_DOWNWARD
3131 crtl
->args
.arg_offset_rtx
3132 = (all
.stack_args_size
.var
== 0 ? GEN_INT (-all
.stack_args_size
.constant
)
3133 : expand_expr (size_diffop (all
.stack_args_size
.var
,
3134 size_int (-all
.stack_args_size
.constant
)),
3135 NULL_RTX
, VOIDmode
, 0));
3137 crtl
->args
.arg_offset_rtx
= ARGS_SIZE_RTX (all
.stack_args_size
);
3140 /* See how many bytes, if any, of its args a function should try to pop
3143 crtl
->args
.pops_args
= RETURN_POPS_ARGS (fndecl
, TREE_TYPE (fndecl
),
3146 /* For stdarg.h function, save info about
3147 regs and stack space used by the named args. */
3149 crtl
->args
.info
= all
.args_so_far
;
3151 /* Set the rtx used for the function return value. Put this in its
3152 own variable so any optimizers that need this information don't have
3153 to include tree.h. Do this here so it gets done when an inlined
3154 function gets output. */
3157 = (DECL_RTL_SET_P (DECL_RESULT (fndecl
))
3158 ? DECL_RTL (DECL_RESULT (fndecl
)) : NULL_RTX
);
3160 /* If scalar return value was computed in a pseudo-reg, or was a named
3161 return value that got dumped to the stack, copy that to the hard
3163 if (DECL_RTL_SET_P (DECL_RESULT (fndecl
)))
3165 tree decl_result
= DECL_RESULT (fndecl
);
3166 rtx decl_rtl
= DECL_RTL (decl_result
);
3168 if (REG_P (decl_rtl
)
3169 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
3170 : DECL_REGISTER (decl_result
))
3174 real_decl_rtl
= targetm
.calls
.function_value (TREE_TYPE (decl_result
),
3176 REG_FUNCTION_VALUE_P (real_decl_rtl
) = 1;
3177 /* The delay slot scheduler assumes that crtl->return_rtx
3178 holds the hard register containing the return value, not a
3179 temporary pseudo. */
3180 crtl
->return_rtx
= real_decl_rtl
;
3185 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3186 For all seen types, gimplify their sizes. */
3189 gimplify_parm_type (tree
*tp
, int *walk_subtrees
, void *data
)
3196 if (POINTER_TYPE_P (t
))
3198 else if (TYPE_SIZE (t
) && !TREE_CONSTANT (TYPE_SIZE (t
))
3199 && !TYPE_SIZES_GIMPLIFIED (t
))
3201 gimplify_type_sizes (t
, (gimple_seq
*) data
);
3209 /* Gimplify the parameter list for current_function_decl. This involves
3210 evaluating SAVE_EXPRs of variable sized parameters and generating code
3211 to implement callee-copies reference parameters. Returns a sequence of
3212 statements to add to the beginning of the function. */
3215 gimplify_parameters (void)
3217 struct assign_parm_data_all all
;
3219 gimple_seq stmts
= NULL
;
3221 assign_parms_initialize_all (&all
);
3222 fnargs
= assign_parms_augmented_arg_list (&all
);
3224 for (parm
= fnargs
; parm
; parm
= TREE_CHAIN (parm
))
3226 struct assign_parm_data_one data
;
3228 /* Extract the type of PARM; adjust it according to ABI. */
3229 assign_parm_find_data_types (&all
, parm
, &data
);
3231 /* Early out for errors and void parameters. */
3232 if (data
.passed_mode
== VOIDmode
|| DECL_SIZE (parm
) == NULL
)
3235 /* Update info on where next arg arrives in registers. */
3236 FUNCTION_ARG_ADVANCE (all
.args_so_far
, data
.promoted_mode
,
3237 data
.passed_type
, data
.named_arg
);
3239 /* ??? Once upon a time variable_size stuffed parameter list
3240 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3241 turned out to be less than manageable in the gimple world.
3242 Now we have to hunt them down ourselves. */
3243 walk_tree_without_duplicates (&data
.passed_type
,
3244 gimplify_parm_type
, &stmts
);
3246 if (TREE_CODE (DECL_SIZE_UNIT (parm
)) != INTEGER_CST
)
3248 gimplify_one_sizepos (&DECL_SIZE (parm
), &stmts
);
3249 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm
), &stmts
);
3252 if (data
.passed_pointer
)
3254 tree type
= TREE_TYPE (data
.passed_type
);
3255 if (reference_callee_copied (&all
.args_so_far
, TYPE_MODE (type
),
3256 type
, data
.named_arg
))
3260 /* For constant-sized objects, this is trivial; for
3261 variable-sized objects, we have to play games. */
3262 if (TREE_CODE (DECL_SIZE_UNIT (parm
)) == INTEGER_CST
3263 && !(flag_stack_check
== GENERIC_STACK_CHECK
3264 && compare_tree_int (DECL_SIZE_UNIT (parm
),
3265 STACK_CHECK_MAX_VAR_SIZE
) > 0))
3267 local
= create_tmp_var (type
, get_name (parm
));
3268 DECL_IGNORED_P (local
) = 0;
3272 tree ptr_type
, addr
;
3274 ptr_type
= build_pointer_type (type
);
3275 addr
= create_tmp_var (ptr_type
, get_name (parm
));
3276 DECL_IGNORED_P (addr
) = 0;
3277 local
= build_fold_indirect_ref (addr
);
3279 t
= built_in_decls
[BUILT_IN_ALLOCA
];
3280 t
= build_call_expr (t
, 1, DECL_SIZE_UNIT (parm
));
3281 t
= fold_convert (ptr_type
, t
);
3282 t
= build2 (MODIFY_EXPR
, TREE_TYPE (addr
), addr
, t
);
3283 gimplify_and_add (t
, &stmts
);
3286 gimplify_assign (local
, parm
, &stmts
);
3288 SET_DECL_VALUE_EXPR (parm
, local
);
3289 DECL_HAS_VALUE_EXPR_P (parm
) = 1;
3297 /* Compute the size and offset from the start of the stacked arguments for a
3298 parm passed in mode PASSED_MODE and with type TYPE.
3300 INITIAL_OFFSET_PTR points to the current offset into the stacked
3303 The starting offset and size for this parm are returned in
3304 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3305 nonzero, the offset is that of stack slot, which is returned in
3306 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3307 padding required from the initial offset ptr to the stack slot.
3309 IN_REGS is nonzero if the argument will be passed in registers. It will
3310 never be set if REG_PARM_STACK_SPACE is not defined.
3312 FNDECL is the function in which the argument was defined.
3314 There are two types of rounding that are done. The first, controlled by
3315 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
3316 list to be aligned to the specific boundary (in bits). This rounding
3317 affects the initial and starting offsets, but not the argument size.
3319 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3320 optionally rounds the size of the parm to PARM_BOUNDARY. The
3321 initial offset is not affected by this rounding, while the size always
3322 is and the starting offset may be. */
3324 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3325 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3326 callers pass in the total size of args so far as
3327 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
3330 locate_and_pad_parm (enum machine_mode passed_mode
, tree type
, int in_regs
,
3331 int partial
, tree fndecl ATTRIBUTE_UNUSED
,
3332 struct args_size
*initial_offset_ptr
,
3333 struct locate_and_pad_arg_data
*locate
)
3336 enum direction where_pad
;
3337 unsigned int boundary
;
3338 int reg_parm_stack_space
= 0;
3339 int part_size_in_regs
;
3341 #ifdef REG_PARM_STACK_SPACE
3342 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
3344 /* If we have found a stack parm before we reach the end of the
3345 area reserved for registers, skip that area. */
3348 if (reg_parm_stack_space
> 0)
3350 if (initial_offset_ptr
->var
)
3352 initial_offset_ptr
->var
3353 = size_binop (MAX_EXPR
, ARGS_SIZE_TREE (*initial_offset_ptr
),
3354 ssize_int (reg_parm_stack_space
));
3355 initial_offset_ptr
->constant
= 0;
3357 else if (initial_offset_ptr
->constant
< reg_parm_stack_space
)
3358 initial_offset_ptr
->constant
= reg_parm_stack_space
;
3361 #endif /* REG_PARM_STACK_SPACE */
3363 part_size_in_regs
= (reg_parm_stack_space
== 0 ? partial
: 0);
3366 = type
? size_in_bytes (type
) : size_int (GET_MODE_SIZE (passed_mode
));
3367 where_pad
= FUNCTION_ARG_PADDING (passed_mode
, type
);
3368 boundary
= FUNCTION_ARG_BOUNDARY (passed_mode
, type
);
3369 locate
->where_pad
= where_pad
;
3371 /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT. */
3372 if (boundary
> MAX_SUPPORTED_STACK_ALIGNMENT
)
3373 boundary
= MAX_SUPPORTED_STACK_ALIGNMENT
;
3375 locate
->boundary
= boundary
;
3377 if (SUPPORTS_STACK_ALIGNMENT
)
3379 /* stack_alignment_estimated can't change after stack has been
3381 if (crtl
->stack_alignment_estimated
< boundary
)
3383 if (!crtl
->stack_realign_processed
)
3384 crtl
->stack_alignment_estimated
= boundary
;
3387 /* If stack is realigned and stack alignment value
3388 hasn't been finalized, it is OK not to increase
3389 stack_alignment_estimated. The bigger alignment
3390 requirement is recorded in stack_alignment_needed
3392 gcc_assert (!crtl
->stack_realign_finalized
3393 && crtl
->stack_realign_needed
);
3398 /* Remember if the outgoing parameter requires extra alignment on the
3399 calling function side. */
3400 if (crtl
->stack_alignment_needed
< boundary
)
3401 crtl
->stack_alignment_needed
= boundary
;
3402 if (crtl
->max_used_stack_slot_alignment
< crtl
->stack_alignment_needed
)
3403 crtl
->max_used_stack_slot_alignment
= crtl
->stack_alignment_needed
;
3404 if (crtl
->preferred_stack_boundary
< boundary
)
3405 crtl
->preferred_stack_boundary
= boundary
;
3407 #ifdef ARGS_GROW_DOWNWARD
3408 locate
->slot_offset
.constant
= -initial_offset_ptr
->constant
;
3409 if (initial_offset_ptr
->var
)
3410 locate
->slot_offset
.var
= size_binop (MINUS_EXPR
, ssize_int (0),
3411 initial_offset_ptr
->var
);
3415 if (where_pad
!= none
3416 && (!host_integerp (sizetree
, 1)
3417 || (tree_low_cst (sizetree
, 1) * BITS_PER_UNIT
) % PARM_BOUNDARY
))
3418 s2
= round_up (s2
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3419 SUB_PARM_SIZE (locate
->slot_offset
, s2
);
3422 locate
->slot_offset
.constant
+= part_size_in_regs
;
3425 #ifdef REG_PARM_STACK_SPACE
3426 || REG_PARM_STACK_SPACE (fndecl
) > 0
3429 pad_to_arg_alignment (&locate
->slot_offset
, boundary
,
3430 &locate
->alignment_pad
);
3432 locate
->size
.constant
= (-initial_offset_ptr
->constant
3433 - locate
->slot_offset
.constant
);
3434 if (initial_offset_ptr
->var
)
3435 locate
->size
.var
= size_binop (MINUS_EXPR
,
3436 size_binop (MINUS_EXPR
,
3438 initial_offset_ptr
->var
),
3439 locate
->slot_offset
.var
);
3441 /* Pad_below needs the pre-rounded size to know how much to pad
3443 locate
->offset
= locate
->slot_offset
;
3444 if (where_pad
== downward
)
3445 pad_below (&locate
->offset
, passed_mode
, sizetree
);
3447 #else /* !ARGS_GROW_DOWNWARD */
3449 #ifdef REG_PARM_STACK_SPACE
3450 || REG_PARM_STACK_SPACE (fndecl
) > 0
3453 pad_to_arg_alignment (initial_offset_ptr
, boundary
,
3454 &locate
->alignment_pad
);
3455 locate
->slot_offset
= *initial_offset_ptr
;
3457 #ifdef PUSH_ROUNDING
3458 if (passed_mode
!= BLKmode
)
3459 sizetree
= size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree
)));
3462 /* Pad_below needs the pre-rounded size to know how much to pad below
3463 so this must be done before rounding up. */
3464 locate
->offset
= locate
->slot_offset
;
3465 if (where_pad
== downward
)
3466 pad_below (&locate
->offset
, passed_mode
, sizetree
);
3468 if (where_pad
!= none
3469 && (!host_integerp (sizetree
, 1)
3470 || (tree_low_cst (sizetree
, 1) * BITS_PER_UNIT
) % PARM_BOUNDARY
))
3471 sizetree
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3473 ADD_PARM_SIZE (locate
->size
, sizetree
);
3475 locate
->size
.constant
-= part_size_in_regs
;
3476 #endif /* ARGS_GROW_DOWNWARD */
3479 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
3480 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
3483 pad_to_arg_alignment (struct args_size
*offset_ptr
, int boundary
,
3484 struct args_size
*alignment_pad
)
3486 tree save_var
= NULL_TREE
;
3487 HOST_WIDE_INT save_constant
= 0;
3488 int boundary_in_bytes
= boundary
/ BITS_PER_UNIT
;
3489 HOST_WIDE_INT sp_offset
= STACK_POINTER_OFFSET
;
3491 #ifdef SPARC_STACK_BOUNDARY_HACK
3492 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
3493 the real alignment of %sp. However, when it does this, the
3494 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
3495 if (SPARC_STACK_BOUNDARY_HACK
)
3499 if (boundary
> PARM_BOUNDARY
)
3501 save_var
= offset_ptr
->var
;
3502 save_constant
= offset_ptr
->constant
;
3505 alignment_pad
->var
= NULL_TREE
;
3506 alignment_pad
->constant
= 0;
3508 if (boundary
> BITS_PER_UNIT
)
3510 if (offset_ptr
->var
)
3512 tree sp_offset_tree
= ssize_int (sp_offset
);
3513 tree offset
= size_binop (PLUS_EXPR
,
3514 ARGS_SIZE_TREE (*offset_ptr
),
3516 #ifdef ARGS_GROW_DOWNWARD
3517 tree rounded
= round_down (offset
, boundary
/ BITS_PER_UNIT
);
3519 tree rounded
= round_up (offset
, boundary
/ BITS_PER_UNIT
);
3522 offset_ptr
->var
= size_binop (MINUS_EXPR
, rounded
, sp_offset_tree
);
3523 /* ARGS_SIZE_TREE includes constant term. */
3524 offset_ptr
->constant
= 0;
3525 if (boundary
> PARM_BOUNDARY
)
3526 alignment_pad
->var
= size_binop (MINUS_EXPR
, offset_ptr
->var
,
3531 offset_ptr
->constant
= -sp_offset
+
3532 #ifdef ARGS_GROW_DOWNWARD
3533 FLOOR_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
3535 CEIL_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
3537 if (boundary
> PARM_BOUNDARY
)
3538 alignment_pad
->constant
= offset_ptr
->constant
- save_constant
;
3544 pad_below (struct args_size
*offset_ptr
, enum machine_mode passed_mode
, tree sizetree
)
3546 if (passed_mode
!= BLKmode
)
3548 if (GET_MODE_BITSIZE (passed_mode
) % PARM_BOUNDARY
)
3549 offset_ptr
->constant
3550 += (((GET_MODE_BITSIZE (passed_mode
) + PARM_BOUNDARY
- 1)
3551 / PARM_BOUNDARY
* PARM_BOUNDARY
/ BITS_PER_UNIT
)
3552 - GET_MODE_SIZE (passed_mode
));
3556 if (TREE_CODE (sizetree
) != INTEGER_CST
3557 || (TREE_INT_CST_LOW (sizetree
) * BITS_PER_UNIT
) % PARM_BOUNDARY
)
3559 /* Round the size up to multiple of PARM_BOUNDARY bits. */
3560 tree s2
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3562 ADD_PARM_SIZE (*offset_ptr
, s2
);
3563 SUB_PARM_SIZE (*offset_ptr
, sizetree
);
3569 /* True if register REGNO was alive at a place where `setjmp' was
3570 called and was set more than once or is an argument. Such regs may
3571 be clobbered by `longjmp'. */
3574 regno_clobbered_at_setjmp (bitmap setjmp_crosses
, int regno
)
3576 /* There appear to be cases where some local vars never reach the
3577 backend but have bogus regnos. */
3578 if (regno
>= max_reg_num ())
3581 return ((REG_N_SETS (regno
) > 1
3582 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR
), regno
))
3583 && REGNO_REG_SET_P (setjmp_crosses
, regno
));
3586 /* Walk the tree of blocks describing the binding levels within a
3587 function and warn about variables the might be killed by setjmp or
3588 vfork. This is done after calling flow_analysis before register
3589 allocation since that will clobber the pseudo-regs to hard
3593 setjmp_vars_warning (bitmap setjmp_crosses
, tree block
)
3597 for (decl
= BLOCK_VARS (block
); decl
; decl
= TREE_CHAIN (decl
))
3599 if (TREE_CODE (decl
) == VAR_DECL
3600 && DECL_RTL_SET_P (decl
)
3601 && REG_P (DECL_RTL (decl
))
3602 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
3603 warning (OPT_Wclobbered
, "variable %q+D might be clobbered by"
3604 " %<longjmp%> or %<vfork%>", decl
);
3607 for (sub
= BLOCK_SUBBLOCKS (block
); sub
; sub
= BLOCK_CHAIN (sub
))
3608 setjmp_vars_warning (setjmp_crosses
, sub
);
3611 /* Do the appropriate part of setjmp_vars_warning
3612 but for arguments instead of local variables. */
3615 setjmp_args_warning (bitmap setjmp_crosses
)
3618 for (decl
= DECL_ARGUMENTS (current_function_decl
);
3619 decl
; decl
= TREE_CHAIN (decl
))
3620 if (DECL_RTL (decl
) != 0
3621 && REG_P (DECL_RTL (decl
))
3622 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
3623 warning (OPT_Wclobbered
,
3624 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
3628 /* Generate warning messages for variables live across setjmp. */
3631 generate_setjmp_warnings (void)
3633 bitmap setjmp_crosses
= regstat_get_setjmp_crosses ();
3635 if (n_basic_blocks
== NUM_FIXED_BLOCKS
3636 || bitmap_empty_p (setjmp_crosses
))
3639 setjmp_vars_warning (setjmp_crosses
, DECL_INITIAL (current_function_decl
));
3640 setjmp_args_warning (setjmp_crosses
);
3644 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
3645 and create duplicate blocks. */
3646 /* ??? Need an option to either create block fragments or to create
3647 abstract origin duplicates of a source block. It really depends
3648 on what optimization has been performed. */
3651 reorder_blocks (void)
3653 tree block
= DECL_INITIAL (current_function_decl
);
3654 VEC(tree
,heap
) *block_stack
;
3656 if (block
== NULL_TREE
)
3659 block_stack
= VEC_alloc (tree
, heap
, 10);
3661 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
3662 clear_block_marks (block
);
3664 /* Prune the old trees away, so that they don't get in the way. */
3665 BLOCK_SUBBLOCKS (block
) = NULL_TREE
;
3666 BLOCK_CHAIN (block
) = NULL_TREE
;
3668 /* Recreate the block tree from the note nesting. */
3669 reorder_blocks_1 (get_insns (), block
, &block_stack
);
3670 BLOCK_SUBBLOCKS (block
) = blocks_nreverse (BLOCK_SUBBLOCKS (block
));
3672 VEC_free (tree
, heap
, block_stack
);
3675 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
3678 clear_block_marks (tree block
)
3682 TREE_ASM_WRITTEN (block
) = 0;
3683 clear_block_marks (BLOCK_SUBBLOCKS (block
));
3684 block
= BLOCK_CHAIN (block
);
3689 reorder_blocks_1 (rtx insns
, tree current_block
, VEC(tree
,heap
) **p_block_stack
)
3693 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
3697 if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_BEG
)
3699 tree block
= NOTE_BLOCK (insn
);
3702 origin
= (BLOCK_FRAGMENT_ORIGIN (block
)
3703 ? BLOCK_FRAGMENT_ORIGIN (block
)
3706 /* If we have seen this block before, that means it now
3707 spans multiple address regions. Create a new fragment. */
3708 if (TREE_ASM_WRITTEN (block
))
3710 tree new_block
= copy_node (block
);
3712 BLOCK_FRAGMENT_ORIGIN (new_block
) = origin
;
3713 BLOCK_FRAGMENT_CHAIN (new_block
)
3714 = BLOCK_FRAGMENT_CHAIN (origin
);
3715 BLOCK_FRAGMENT_CHAIN (origin
) = new_block
;
3717 NOTE_BLOCK (insn
) = new_block
;
3721 BLOCK_SUBBLOCKS (block
) = 0;
3722 TREE_ASM_WRITTEN (block
) = 1;
3723 /* When there's only one block for the entire function,
3724 current_block == block and we mustn't do this, it
3725 will cause infinite recursion. */
3726 if (block
!= current_block
)
3728 if (block
!= origin
)
3729 gcc_assert (BLOCK_SUPERCONTEXT (origin
) == current_block
);
3731 BLOCK_SUPERCONTEXT (block
) = current_block
;
3732 BLOCK_CHAIN (block
) = BLOCK_SUBBLOCKS (current_block
);
3733 BLOCK_SUBBLOCKS (current_block
) = block
;
3734 current_block
= origin
;
3736 VEC_safe_push (tree
, heap
, *p_block_stack
, block
);
3738 else if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_END
)
3740 NOTE_BLOCK (insn
) = VEC_pop (tree
, *p_block_stack
);
3741 BLOCK_SUBBLOCKS (current_block
)
3742 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block
));
3743 current_block
= BLOCK_SUPERCONTEXT (current_block
);
3749 /* Reverse the order of elements in the chain T of blocks,
3750 and return the new head of the chain (old last element). */
3753 blocks_nreverse (tree t
)
3755 tree prev
= 0, decl
, next
;
3756 for (decl
= t
; decl
; decl
= next
)
3758 next
= BLOCK_CHAIN (decl
);
3759 BLOCK_CHAIN (decl
) = prev
;
3765 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
3766 non-NULL, list them all into VECTOR, in a depth-first preorder
3767 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
3771 all_blocks (tree block
, tree
*vector
)
3777 TREE_ASM_WRITTEN (block
) = 0;
3779 /* Record this block. */
3781 vector
[n_blocks
] = block
;
3785 /* Record the subblocks, and their subblocks... */
3786 n_blocks
+= all_blocks (BLOCK_SUBBLOCKS (block
),
3787 vector
? vector
+ n_blocks
: 0);
3788 block
= BLOCK_CHAIN (block
);
3794 /* Return a vector containing all the blocks rooted at BLOCK. The
3795 number of elements in the vector is stored in N_BLOCKS_P. The
3796 vector is dynamically allocated; it is the caller's responsibility
3797 to call `free' on the pointer returned. */
3800 get_block_vector (tree block
, int *n_blocks_p
)
3804 *n_blocks_p
= all_blocks (block
, NULL
);
3805 block_vector
= XNEWVEC (tree
, *n_blocks_p
);
3806 all_blocks (block
, block_vector
);
3808 return block_vector
;
3811 static GTY(()) int next_block_index
= 2;
3813 /* Set BLOCK_NUMBER for all the blocks in FN. */
3816 number_blocks (tree fn
)
3822 /* For SDB and XCOFF debugging output, we start numbering the blocks
3823 from 1 within each function, rather than keeping a running
3825 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
3826 if (write_symbols
== SDB_DEBUG
|| write_symbols
== XCOFF_DEBUG
)
3827 next_block_index
= 1;
3830 block_vector
= get_block_vector (DECL_INITIAL (fn
), &n_blocks
);
3832 /* The top-level BLOCK isn't numbered at all. */
3833 for (i
= 1; i
< n_blocks
; ++i
)
3834 /* We number the blocks from two. */
3835 BLOCK_NUMBER (block_vector
[i
]) = next_block_index
++;
3837 free (block_vector
);
3842 /* If VAR is present in a subblock of BLOCK, return the subblock. */
3845 debug_find_var_in_block_tree (tree var
, tree block
)
3849 for (t
= BLOCK_VARS (block
); t
; t
= TREE_CHAIN (t
))
3853 for (t
= BLOCK_SUBBLOCKS (block
); t
; t
= TREE_CHAIN (t
))
3855 tree ret
= debug_find_var_in_block_tree (var
, t
);
3863 /* Keep track of whether we're in a dummy function context. If we are,
3864 we don't want to invoke the set_current_function hook, because we'll
3865 get into trouble if the hook calls target_reinit () recursively or
3866 when the initial initialization is not yet complete. */
3868 static bool in_dummy_function
;
3870 /* Invoke the target hook when setting cfun. Update the optimization options
3871 if the function uses different options than the default. */
3874 invoke_set_current_function_hook (tree fndecl
)
3876 if (!in_dummy_function
)
3878 tree opts
= ((fndecl
)
3879 ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl
)
3880 : optimization_default_node
);
3883 opts
= optimization_default_node
;
3885 /* Change optimization options if needed. */
3886 if (optimization_current_node
!= opts
)
3888 optimization_current_node
= opts
;
3889 cl_optimization_restore (TREE_OPTIMIZATION (opts
));
3892 targetm
.set_current_function (fndecl
);
3896 /* cfun should never be set directly; use this function. */
3899 set_cfun (struct function
*new_cfun
)
3901 if (cfun
!= new_cfun
)
3904 invoke_set_current_function_hook (new_cfun
? new_cfun
->decl
: NULL_TREE
);
3908 /* Keep track of the cfun stack. */
3910 typedef struct function
*function_p
;
3912 DEF_VEC_P(function_p
);
3913 DEF_VEC_ALLOC_P(function_p
,heap
);
3915 /* Initialized with NOGC, making this poisonous to the garbage collector. */
3917 static VEC(function_p
,heap
) *cfun_stack
;
3919 /* Push the current cfun onto the stack, and set cfun to new_cfun. */
3922 push_cfun (struct function
*new_cfun
)
3924 VEC_safe_push (function_p
, heap
, cfun_stack
, cfun
);
3925 set_cfun (new_cfun
);
3928 /* Pop cfun from the stack. */
3933 struct function
*new_cfun
= VEC_pop (function_p
, cfun_stack
);
3934 set_cfun (new_cfun
);
3937 /* Return value of funcdef and increase it. */
3939 get_next_funcdef_no (void)
3941 return funcdef_no
++;
3944 /* Allocate a function structure for FNDECL and set its contents
3945 to the defaults. Set cfun to the newly-allocated object.
3946 Some of the helper functions invoked during initialization assume
3947 that cfun has already been set. Therefore, assign the new object
3948 directly into cfun and invoke the back end hook explicitly at the
3949 very end, rather than initializing a temporary and calling set_cfun
3952 ABSTRACT_P is true if this is a function that will never be seen by
3953 the middle-end. Such functions are front-end concepts (like C++
3954 function templates) that do not correspond directly to functions
3955 placed in object files. */
3958 allocate_struct_function (tree fndecl
, bool abstract_p
)
3961 tree fntype
= fndecl
? TREE_TYPE (fndecl
) : NULL_TREE
;
3963 cfun
= GGC_CNEW (struct function
);
3965 cfun
->function_frequency
= FUNCTION_FREQUENCY_NORMAL
;
3967 init_eh_for_function ();
3969 if (init_machine_status
)
3970 cfun
->machine
= (*init_machine_status
) ();
3972 #ifdef OVERRIDE_ABI_FORMAT
3973 OVERRIDE_ABI_FORMAT (fndecl
);
3976 if (fndecl
!= NULL_TREE
)
3978 DECL_STRUCT_FUNCTION (fndecl
) = cfun
;
3979 cfun
->decl
= fndecl
;
3980 current_function_funcdef_no
= get_next_funcdef_no ();
3982 result
= DECL_RESULT (fndecl
);
3983 if (!abstract_p
&& aggregate_value_p (result
, fndecl
))
3985 #ifdef PCC_STATIC_STRUCT_RETURN
3986 cfun
->returns_pcc_struct
= 1;
3988 cfun
->returns_struct
= 1;
3993 && TYPE_ARG_TYPES (fntype
) != 0
3994 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype
)))
3995 != void_type_node
));
3997 /* Assume all registers in stdarg functions need to be saved. */
3998 cfun
->va_list_gpr_size
= VA_LIST_MAX_GPR_SIZE
;
3999 cfun
->va_list_fpr_size
= VA_LIST_MAX_FPR_SIZE
;
4002 invoke_set_current_function_hook (fndecl
);
4005 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
4006 instead of just setting it. */
4009 push_struct_function (tree fndecl
)
4011 VEC_safe_push (function_p
, heap
, cfun_stack
, cfun
);
4012 allocate_struct_function (fndecl
, false);
4015 /* Reset cfun, and other non-struct-function variables to defaults as
4016 appropriate for emitting rtl at the start of a function. */
4019 prepare_function_start (void)
4021 gcc_assert (!crtl
->emit
.x_last_insn
);
4023 init_varasm_status ();
4025 default_rtl_profile ();
4027 cse_not_expected
= ! optimize
;
4029 /* Caller save not needed yet. */
4030 caller_save_needed
= 0;
4032 /* We haven't done register allocation yet. */
4035 /* Indicate that we have not instantiated virtual registers yet. */
4036 virtuals_instantiated
= 0;
4038 /* Indicate that we want CONCATs now. */
4039 generating_concat_p
= 1;
4041 /* Indicate we have no need of a frame pointer yet. */
4042 frame_pointer_needed
= 0;
4045 /* Initialize the rtl expansion mechanism so that we can do simple things
4046 like generate sequences. This is used to provide a context during global
4047 initialization of some passes. You must call expand_dummy_function_end
4048 to exit this context. */
4051 init_dummy_function_start (void)
4053 gcc_assert (!in_dummy_function
);
4054 in_dummy_function
= true;
4055 push_struct_function (NULL_TREE
);
4056 prepare_function_start ();
4059 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
4060 and initialize static variables for generating RTL for the statements
4064 init_function_start (tree subr
)
4066 if (subr
&& DECL_STRUCT_FUNCTION (subr
))
4067 set_cfun (DECL_STRUCT_FUNCTION (subr
));
4069 allocate_struct_function (subr
, false);
4070 prepare_function_start ();
4072 /* Warn if this value is an aggregate type,
4073 regardless of which calling convention we are using for it. */
4074 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr
))))
4075 warning (OPT_Waggregate_return
, "function returns an aggregate");
4078 /* Make sure all values used by the optimization passes have sane
4081 init_function_for_compilation (void)
4085 /* No prologue/epilogue insns yet. Make sure that these vectors are
4087 gcc_assert (VEC_length (int, prologue
) == 0);
4088 gcc_assert (VEC_length (int, epilogue
) == 0);
4089 gcc_assert (VEC_length (int, sibcall_epilogue
) == 0);
4093 struct rtl_opt_pass pass_init_function
=
4099 init_function_for_compilation
, /* execute */
4102 0, /* static_pass_number */
4104 0, /* properties_required */
4105 0, /* properties_provided */
4106 0, /* properties_destroyed */
4107 0, /* todo_flags_start */
4108 0 /* todo_flags_finish */
4114 expand_main_function (void)
4116 #if (defined(INVOKE__main) \
4117 || (!defined(HAS_INIT_SECTION) \
4118 && !defined(INIT_SECTION_ASM_OP) \
4119 && !defined(INIT_ARRAY_SECTION_ASM_OP)))
4120 emit_library_call (init_one_libfunc (NAME__MAIN
), LCT_NORMAL
, VOIDmode
, 0);
4124 /* Expand code to initialize the stack_protect_guard. This is invoked at
4125 the beginning of a function to be protected. */
4127 #ifndef HAVE_stack_protect_set
4128 # define HAVE_stack_protect_set 0
4129 # define gen_stack_protect_set(x,y) (gcc_unreachable (), NULL_RTX)
4133 stack_protect_prologue (void)
4135 tree guard_decl
= targetm
.stack_protect_guard ();
4138 /* Avoid expand_expr here, because we don't want guard_decl pulled
4139 into registers unless absolutely necessary. And we know that
4140 crtl->stack_protect_guard is a local stack slot, so this skips
4142 x
= validize_mem (DECL_RTL (crtl
->stack_protect_guard
));
4143 y
= validize_mem (DECL_RTL (guard_decl
));
4145 /* Allow the target to copy from Y to X without leaking Y into a
4147 if (HAVE_stack_protect_set
)
4149 rtx insn
= gen_stack_protect_set (x
, y
);
4157 /* Otherwise do a straight move. */
4158 emit_move_insn (x
, y
);
4161 /* Expand code to verify the stack_protect_guard. This is invoked at
4162 the end of a function to be protected. */
4164 #ifndef HAVE_stack_protect_test
4165 # define HAVE_stack_protect_test 0
4166 # define gen_stack_protect_test(x, y, z) (gcc_unreachable (), NULL_RTX)
4170 stack_protect_epilogue (void)
4172 tree guard_decl
= targetm
.stack_protect_guard ();
4173 rtx label
= gen_label_rtx ();
4176 /* Avoid expand_expr here, because we don't want guard_decl pulled
4177 into registers unless absolutely necessary. And we know that
4178 crtl->stack_protect_guard is a local stack slot, so this skips
4180 x
= validize_mem (DECL_RTL (crtl
->stack_protect_guard
));
4181 y
= validize_mem (DECL_RTL (guard_decl
));
4183 /* Allow the target to compare Y with X without leaking either into
4185 switch (HAVE_stack_protect_test
!= 0)
4188 tmp
= gen_stack_protect_test (x
, y
, label
);
4197 emit_cmp_and_jump_insns (x
, y
, EQ
, NULL_RTX
, ptr_mode
, 1, label
);
4201 /* The noreturn predictor has been moved to the tree level. The rtl-level
4202 predictors estimate this branch about 20%, which isn't enough to get
4203 things moved out of line. Since this is the only extant case of adding
4204 a noreturn function at the rtl level, it doesn't seem worth doing ought
4205 except adding the prediction by hand. */
4206 tmp
= get_last_insn ();
4208 predict_insn_def (tmp
, PRED_NORETURN
, TAKEN
);
4210 expand_expr_stmt (targetm
.stack_protect_fail ());
4214 /* Start the RTL for a new function, and set variables used for
4216 SUBR is the FUNCTION_DECL node.
4217 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4218 the function's parameters, which must be run at any return statement. */
4221 expand_function_start (tree subr
)
4223 /* Make sure volatile mem refs aren't considered
4224 valid operands of arithmetic insns. */
4225 init_recog_no_volatile ();
4229 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr
));
4232 = (stack_limit_rtx
!= NULL_RTX
&& ! DECL_NO_LIMIT_STACK (subr
));
4234 /* Make the label for return statements to jump to. Do not special
4235 case machines with special return instructions -- they will be
4236 handled later during jump, ifcvt, or epilogue creation. */
4237 return_label
= gen_label_rtx ();
4239 /* Initialize rtx used to return the value. */
4240 /* Do this before assign_parms so that we copy the struct value address
4241 before any library calls that assign parms might generate. */
4243 /* Decide whether to return the value in memory or in a register. */
4244 if (aggregate_value_p (DECL_RESULT (subr
), subr
))
4246 /* Returning something that won't go in a register. */
4247 rtx value_address
= 0;
4249 #ifdef PCC_STATIC_STRUCT_RETURN
4250 if (cfun
->returns_pcc_struct
)
4252 int size
= int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr
)));
4253 value_address
= assemble_static_space (size
);
4258 rtx sv
= targetm
.calls
.struct_value_rtx (TREE_TYPE (subr
), 2);
4259 /* Expect to be passed the address of a place to store the value.
4260 If it is passed as an argument, assign_parms will take care of
4264 value_address
= gen_reg_rtx (Pmode
);
4265 emit_move_insn (value_address
, sv
);
4270 rtx x
= value_address
;
4271 if (!DECL_BY_REFERENCE (DECL_RESULT (subr
)))
4273 x
= gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr
)), x
);
4274 set_mem_attributes (x
, DECL_RESULT (subr
), 1);
4276 SET_DECL_RTL (DECL_RESULT (subr
), x
);
4279 else if (DECL_MODE (DECL_RESULT (subr
)) == VOIDmode
)
4280 /* If return mode is void, this decl rtl should not be used. */
4281 SET_DECL_RTL (DECL_RESULT (subr
), NULL_RTX
);
4284 /* Compute the return values into a pseudo reg, which we will copy
4285 into the true return register after the cleanups are done. */
4286 tree return_type
= TREE_TYPE (DECL_RESULT (subr
));
4287 if (TYPE_MODE (return_type
) != BLKmode
4288 && targetm
.calls
.return_in_msb (return_type
))
4289 /* expand_function_end will insert the appropriate padding in
4290 this case. Use the return value's natural (unpadded) mode
4291 within the function proper. */
4292 SET_DECL_RTL (DECL_RESULT (subr
),
4293 gen_reg_rtx (TYPE_MODE (return_type
)));
4296 /* In order to figure out what mode to use for the pseudo, we
4297 figure out what the mode of the eventual return register will
4298 actually be, and use that. */
4299 rtx hard_reg
= hard_function_value (return_type
, subr
, 0, 1);
4301 /* Structures that are returned in registers are not
4302 aggregate_value_p, so we may see a PARALLEL or a REG. */
4303 if (REG_P (hard_reg
))
4304 SET_DECL_RTL (DECL_RESULT (subr
),
4305 gen_reg_rtx (GET_MODE (hard_reg
)));
4308 gcc_assert (GET_CODE (hard_reg
) == PARALLEL
);
4309 SET_DECL_RTL (DECL_RESULT (subr
), gen_group_rtx (hard_reg
));
4313 /* Set DECL_REGISTER flag so that expand_function_end will copy the
4314 result to the real return register(s). */
4315 DECL_REGISTER (DECL_RESULT (subr
)) = 1;
4318 /* Initialize rtx for parameters and local variables.
4319 In some cases this requires emitting insns. */
4320 assign_parms (subr
);
4322 /* If function gets a static chain arg, store it. */
4323 if (cfun
->static_chain_decl
)
4325 tree parm
= cfun
->static_chain_decl
;
4326 rtx local
= gen_reg_rtx (Pmode
);
4328 set_decl_incoming_rtl (parm
, static_chain_incoming_rtx
, false);
4329 SET_DECL_RTL (parm
, local
);
4330 mark_reg_pointer (local
, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
4332 emit_move_insn (local
, static_chain_incoming_rtx
);
4335 /* If the function receives a non-local goto, then store the
4336 bits we need to restore the frame pointer. */
4337 if (cfun
->nonlocal_goto_save_area
)
4342 /* ??? We need to do this save early. Unfortunately here is
4343 before the frame variable gets declared. Help out... */
4344 tree var
= TREE_OPERAND (cfun
->nonlocal_goto_save_area
, 0);
4345 if (!DECL_RTL_SET_P (var
))
4348 t_save
= build4 (ARRAY_REF
, ptr_type_node
,
4349 cfun
->nonlocal_goto_save_area
,
4350 integer_zero_node
, NULL_TREE
, NULL_TREE
);
4351 r_save
= expand_expr (t_save
, NULL_RTX
, VOIDmode
, EXPAND_WRITE
);
4352 r_save
= convert_memory_address (Pmode
, r_save
);
4354 emit_move_insn (r_save
, targetm
.builtin_setjmp_frame_value ());
4355 update_nonlocal_goto_save_area ();
4358 /* The following was moved from init_function_start.
4359 The move is supposed to make sdb output more accurate. */
4360 /* Indicate the beginning of the function body,
4361 as opposed to parm setup. */
4362 emit_note (NOTE_INSN_FUNCTION_BEG
);
4364 gcc_assert (NOTE_P (get_last_insn ()));
4366 parm_birth_insn
= get_last_insn ();
4371 PROFILE_HOOK (current_function_funcdef_no
);
4375 /* After the display initializations is where the stack checking
4377 if(flag_stack_check
)
4378 stack_check_probe_note
= emit_note (NOTE_INSN_DELETED
);
4380 /* Make sure there is a line number after the function entry setup code. */
4381 force_next_line_note ();
4384 /* Undo the effects of init_dummy_function_start. */
4386 expand_dummy_function_end (void)
4388 gcc_assert (in_dummy_function
);
4390 /* End any sequences that failed to be closed due to syntax errors. */
4391 while (in_sequence_p ())
4394 /* Outside function body, can't compute type's actual size
4395 until next function's body starts. */
4397 free_after_parsing (cfun
);
4398 free_after_compilation (cfun
);
4400 in_dummy_function
= false;
4403 /* Call DOIT for each hard register used as a return value from
4404 the current function. */
4407 diddle_return_value (void (*doit
) (rtx
, void *), void *arg
)
4409 rtx outgoing
= crtl
->return_rtx
;
4414 if (REG_P (outgoing
))
4415 (*doit
) (outgoing
, arg
);
4416 else if (GET_CODE (outgoing
) == PARALLEL
)
4420 for (i
= 0; i
< XVECLEN (outgoing
, 0); i
++)
4422 rtx x
= XEXP (XVECEXP (outgoing
, 0, i
), 0);
4424 if (REG_P (x
) && REGNO (x
) < FIRST_PSEUDO_REGISTER
)
4431 do_clobber_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
4437 clobber_return_register (void)
4439 diddle_return_value (do_clobber_return_reg
, NULL
);
4441 /* In case we do use pseudo to return value, clobber it too. */
4442 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
4444 tree decl_result
= DECL_RESULT (current_function_decl
);
4445 rtx decl_rtl
= DECL_RTL (decl_result
);
4446 if (REG_P (decl_rtl
) && REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
)
4448 do_clobber_return_reg (decl_rtl
, NULL
);
4454 do_use_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
4460 use_return_register (void)
4462 diddle_return_value (do_use_return_reg
, NULL
);
4465 /* Possibly warn about unused parameters. */
4467 do_warn_unused_parameter (tree fn
)
4471 for (decl
= DECL_ARGUMENTS (fn
);
4472 decl
; decl
= TREE_CHAIN (decl
))
4473 if (!TREE_USED (decl
) && TREE_CODE (decl
) == PARM_DECL
4474 && DECL_NAME (decl
) && !DECL_ARTIFICIAL (decl
)
4475 && !TREE_NO_WARNING (decl
))
4476 warning (OPT_Wunused_parameter
, "unused parameter %q+D", decl
);
4479 static GTY(()) rtx initial_trampoline
;
4481 /* Generate RTL for the end of the current function. */
4484 expand_function_end (void)
4488 /* If arg_pointer_save_area was referenced only from a nested
4489 function, we will not have initialized it yet. Do that now. */
4490 if (arg_pointer_save_area
&& ! crtl
->arg_pointer_save_area_init
)
4491 get_arg_pointer_save_area ();
4493 /* If we are doing generic stack checking and this function makes calls,
4494 do a stack probe at the start of the function to ensure we have enough
4495 space for another stack frame. */
4496 if (flag_stack_check
== GENERIC_STACK_CHECK
)
4500 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
4504 probe_stack_range (STACK_OLD_CHECK_PROTECT
,
4505 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE
));
4508 emit_insn_before (seq
, stack_check_probe_note
);
4513 /* End any sequences that failed to be closed due to syntax errors. */
4514 while (in_sequence_p ())
4517 clear_pending_stack_adjust ();
4518 do_pending_stack_adjust ();
4520 /* Output a linenumber for the end of the function.
4521 SDB depends on this. */
4522 force_next_line_note ();
4523 set_curr_insn_source_location (input_location
);
4525 /* Before the return label (if any), clobber the return
4526 registers so that they are not propagated live to the rest of
4527 the function. This can only happen with functions that drop
4528 through; if there had been a return statement, there would
4529 have either been a return rtx, or a jump to the return label.
4531 We delay actual code generation after the current_function_value_rtx
4533 clobber_after
= get_last_insn ();
4535 /* Output the label for the actual return from the function. */
4536 emit_label (return_label
);
4538 if (USING_SJLJ_EXCEPTIONS
)
4540 /* Let except.c know where it should emit the call to unregister
4541 the function context for sjlj exceptions. */
4542 if (flag_exceptions
)
4543 sjlj_emit_function_exit_after (get_last_insn ());
4547 /* We want to ensure that instructions that may trap are not
4548 moved into the epilogue by scheduling, because we don't
4549 always emit unwind information for the epilogue. */
4550 if (flag_non_call_exceptions
)
4551 emit_insn (gen_blockage ());
4554 /* If this is an implementation of throw, do what's necessary to
4555 communicate between __builtin_eh_return and the epilogue. */
4556 expand_eh_return ();
4558 /* If scalar return value was computed in a pseudo-reg, or was a named
4559 return value that got dumped to the stack, copy that to the hard
4561 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
4563 tree decl_result
= DECL_RESULT (current_function_decl
);
4564 rtx decl_rtl
= DECL_RTL (decl_result
);
4566 if (REG_P (decl_rtl
)
4567 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
4568 : DECL_REGISTER (decl_result
))
4570 rtx real_decl_rtl
= crtl
->return_rtx
;
4572 /* This should be set in assign_parms. */
4573 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl
));
4575 /* If this is a BLKmode structure being returned in registers,
4576 then use the mode computed in expand_return. Note that if
4577 decl_rtl is memory, then its mode may have been changed,
4578 but that crtl->return_rtx has not. */
4579 if (GET_MODE (real_decl_rtl
) == BLKmode
)
4580 PUT_MODE (real_decl_rtl
, GET_MODE (decl_rtl
));
4582 /* If a non-BLKmode return value should be padded at the least
4583 significant end of the register, shift it left by the appropriate
4584 amount. BLKmode results are handled using the group load/store
4586 if (TYPE_MODE (TREE_TYPE (decl_result
)) != BLKmode
4587 && targetm
.calls
.return_in_msb (TREE_TYPE (decl_result
)))
4589 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl
),
4590 REGNO (real_decl_rtl
)),
4592 shift_return_value (GET_MODE (decl_rtl
), true, real_decl_rtl
);
4594 /* If a named return value dumped decl_return to memory, then
4595 we may need to re-do the PROMOTE_MODE signed/unsigned
4597 else if (GET_MODE (real_decl_rtl
) != GET_MODE (decl_rtl
))
4599 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (decl_result
));
4601 if (targetm
.calls
.promote_function_return (TREE_TYPE (current_function_decl
)))
4602 promote_mode (TREE_TYPE (decl_result
), GET_MODE (decl_rtl
),
4605 convert_move (real_decl_rtl
, decl_rtl
, unsignedp
);
4607 else if (GET_CODE (real_decl_rtl
) == PARALLEL
)
4609 /* If expand_function_start has created a PARALLEL for decl_rtl,
4610 move the result to the real return registers. Otherwise, do
4611 a group load from decl_rtl for a named return. */
4612 if (GET_CODE (decl_rtl
) == PARALLEL
)
4613 emit_group_move (real_decl_rtl
, decl_rtl
);
4615 emit_group_load (real_decl_rtl
, decl_rtl
,
4616 TREE_TYPE (decl_result
),
4617 int_size_in_bytes (TREE_TYPE (decl_result
)));
4619 /* In the case of complex integer modes smaller than a word, we'll
4620 need to generate some non-trivial bitfield insertions. Do that
4621 on a pseudo and not the hard register. */
4622 else if (GET_CODE (decl_rtl
) == CONCAT
4623 && GET_MODE_CLASS (GET_MODE (decl_rtl
)) == MODE_COMPLEX_INT
4624 && GET_MODE_BITSIZE (GET_MODE (decl_rtl
)) <= BITS_PER_WORD
)
4626 int old_generating_concat_p
;
4629 old_generating_concat_p
= generating_concat_p
;
4630 generating_concat_p
= 0;
4631 tmp
= gen_reg_rtx (GET_MODE (decl_rtl
));
4632 generating_concat_p
= old_generating_concat_p
;
4634 emit_move_insn (tmp
, decl_rtl
);
4635 emit_move_insn (real_decl_rtl
, tmp
);
4638 emit_move_insn (real_decl_rtl
, decl_rtl
);
4642 /* If returning a structure, arrange to return the address of the value
4643 in a place where debuggers expect to find it.
4645 If returning a structure PCC style,
4646 the caller also depends on this value.
4647 And cfun->returns_pcc_struct is not necessarily set. */
4648 if (cfun
->returns_struct
4649 || cfun
->returns_pcc_struct
)
4651 rtx value_address
= DECL_RTL (DECL_RESULT (current_function_decl
));
4652 tree type
= TREE_TYPE (DECL_RESULT (current_function_decl
));
4655 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl
)))
4656 type
= TREE_TYPE (type
);
4658 value_address
= XEXP (value_address
, 0);
4660 outgoing
= targetm
.calls
.function_value (build_pointer_type (type
),
4661 current_function_decl
, true);
4663 /* Mark this as a function return value so integrate will delete the
4664 assignment and USE below when inlining this function. */
4665 REG_FUNCTION_VALUE_P (outgoing
) = 1;
4667 /* The address may be ptr_mode and OUTGOING may be Pmode. */
4668 value_address
= convert_memory_address (GET_MODE (outgoing
),
4671 emit_move_insn (outgoing
, value_address
);
4673 /* Show return register used to hold result (in this case the address
4675 crtl
->return_rtx
= outgoing
;
4678 /* Emit the actual code to clobber return register. */
4683 clobber_return_register ();
4684 expand_naked_return ();
4688 emit_insn_after (seq
, clobber_after
);
4691 /* Output the label for the naked return from the function. */
4692 emit_label (naked_return_label
);
4694 /* @@@ This is a kludge. We want to ensure that instructions that
4695 may trap are not moved into the epilogue by scheduling, because
4696 we don't always emit unwind information for the epilogue. */
4697 if (! USING_SJLJ_EXCEPTIONS
&& flag_non_call_exceptions
)
4698 emit_insn (gen_blockage ());
4700 /* If stack protection is enabled for this function, check the guard. */
4701 if (crtl
->stack_protect_guard
)
4702 stack_protect_epilogue ();
4704 /* If we had calls to alloca, and this machine needs
4705 an accurate stack pointer to exit the function,
4706 insert some code to save and restore the stack pointer. */
4707 if (! EXIT_IGNORE_STACK
4708 && cfun
->calls_alloca
)
4712 emit_stack_save (SAVE_FUNCTION
, &tem
, parm_birth_insn
);
4713 emit_stack_restore (SAVE_FUNCTION
, tem
, NULL_RTX
);
4716 /* ??? This should no longer be necessary since stupid is no longer with
4717 us, but there are some parts of the compiler (eg reload_combine, and
4718 sh mach_dep_reorg) that still try and compute their own lifetime info
4719 instead of using the general framework. */
4720 use_return_register ();
4724 get_arg_pointer_save_area (void)
4726 rtx ret
= arg_pointer_save_area
;
4730 ret
= assign_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0);
4731 arg_pointer_save_area
= ret
;
4734 if (! crtl
->arg_pointer_save_area_init
)
4738 /* Save the arg pointer at the beginning of the function. The
4739 generated stack slot may not be a valid memory address, so we
4740 have to check it and fix it if necessary. */
4742 emit_move_insn (validize_mem (ret
),
4743 crtl
->args
.internal_arg_pointer
);
4747 push_topmost_sequence ();
4748 emit_insn_after (seq
, entry_of_function ());
4749 pop_topmost_sequence ();
4755 /* Extend a vector that records the INSN_UIDs of INSNS
4756 (a list of one or more insns). */
4759 record_insns (rtx insns
, VEC(int,heap
) **vecp
)
4763 for (tmp
= insns
; tmp
!= NULL_RTX
; tmp
= NEXT_INSN (tmp
))
4764 VEC_safe_push (int, heap
, *vecp
, INSN_UID (tmp
));
4767 /* Set the locator of the insn chain starting at INSN to LOC. */
4769 set_insn_locators (rtx insn
, int loc
)
4771 while (insn
!= NULL_RTX
)
4774 INSN_LOCATOR (insn
) = loc
;
4775 insn
= NEXT_INSN (insn
);
4779 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
4780 be running after reorg, SEQUENCE rtl is possible. */
4783 contains (const_rtx insn
, VEC(int,heap
) **vec
)
4787 if (NONJUMP_INSN_P (insn
)
4788 && GET_CODE (PATTERN (insn
)) == SEQUENCE
)
4791 for (i
= XVECLEN (PATTERN (insn
), 0) - 1; i
>= 0; i
--)
4792 for (j
= VEC_length (int, *vec
) - 1; j
>= 0; --j
)
4793 if (INSN_UID (XVECEXP (PATTERN (insn
), 0, i
))
4794 == VEC_index (int, *vec
, j
))
4800 for (j
= VEC_length (int, *vec
) - 1; j
>= 0; --j
)
4801 if (INSN_UID (insn
) == VEC_index (int, *vec
, j
))
4808 prologue_epilogue_contains (const_rtx insn
)
4810 if (contains (insn
, &prologue
))
4812 if (contains (insn
, &epilogue
))
4818 sibcall_epilogue_contains (const_rtx insn
)
4820 if (sibcall_epilogue
)
4821 return contains (insn
, &sibcall_epilogue
);
4826 /* Insert gen_return at the end of block BB. This also means updating
4827 block_for_insn appropriately. */
4830 emit_return_into_block (basic_block bb
)
4832 emit_jump_insn_after (gen_return (), BB_END (bb
));
4834 #endif /* HAVE_return */
4836 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
4837 this into place with notes indicating where the prologue ends and where
4838 the epilogue begins. Update the basic block information when possible. */
4841 thread_prologue_and_epilogue_insns (void)
4845 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
4848 #if defined (HAVE_epilogue) || defined(HAVE_return)
4849 rtx epilogue_end
= NULL_RTX
;
4853 rtl_profile_for_bb (ENTRY_BLOCK_PTR
);
4854 #ifdef HAVE_prologue
4858 seq
= gen_prologue ();
4861 /* Insert an explicit USE for the frame pointer
4862 if the profiling is on and the frame pointer is required. */
4863 if (crtl
->profile
&& frame_pointer_needed
)
4864 emit_use (hard_frame_pointer_rtx
);
4866 /* Retain a map of the prologue insns. */
4867 record_insns (seq
, &prologue
);
4868 emit_note (NOTE_INSN_PROLOGUE_END
);
4870 #ifndef PROFILE_BEFORE_PROLOGUE
4871 /* Ensure that instructions are not moved into the prologue when
4872 profiling is on. The call to the profiling routine can be
4873 emitted within the live range of a call-clobbered register. */
4875 emit_insn (gen_blockage ());
4880 set_insn_locators (seq
, prologue_locator
);
4882 /* Can't deal with multiple successors of the entry block
4883 at the moment. Function should always have at least one
4885 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR
));
4887 insert_insn_on_edge (seq
, single_succ_edge (ENTRY_BLOCK_PTR
));
4892 /* If the exit block has no non-fake predecessors, we don't need
4894 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
4895 if ((e
->flags
& EDGE_FAKE
) == 0)
4900 rtl_profile_for_bb (EXIT_BLOCK_PTR
);
4902 if (optimize
&& HAVE_return
)
4904 /* If we're allowed to generate a simple return instruction,
4905 then by definition we don't need a full epilogue. Examine
4906 the block that falls through to EXIT. If it does not
4907 contain any code, examine its predecessors and try to
4908 emit (conditional) return instructions. */
4913 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
4914 if (e
->flags
& EDGE_FALLTHRU
)
4920 /* Verify that there are no active instructions in the last block. */
4921 label
= BB_END (last
);
4922 while (label
&& !LABEL_P (label
))
4924 if (active_insn_p (label
))
4926 label
= PREV_INSN (label
);
4929 if (BB_HEAD (last
) == label
&& LABEL_P (label
))
4933 for (ei2
= ei_start (last
->preds
); (e
= ei_safe_edge (ei2
)); )
4935 basic_block bb
= e
->src
;
4938 if (bb
== ENTRY_BLOCK_PTR
)
4945 if (!JUMP_P (jump
) || JUMP_LABEL (jump
) != label
)
4951 /* If we have an unconditional jump, we can replace that
4952 with a simple return instruction. */
4953 if (simplejump_p (jump
))
4955 emit_return_into_block (bb
);
4959 /* If we have a conditional jump, we can try to replace
4960 that with a conditional return instruction. */
4961 else if (condjump_p (jump
))
4963 if (! redirect_jump (jump
, 0, 0))
4969 /* If this block has only one successor, it both jumps
4970 and falls through to the fallthru block, so we can't
4972 if (single_succ_p (bb
))
4984 /* Fix up the CFG for the successful change we just made. */
4985 redirect_edge_succ (e
, EXIT_BLOCK_PTR
);
4988 /* Emit a return insn for the exit fallthru block. Whether
4989 this is still reachable will be determined later. */
4991 emit_barrier_after (BB_END (last
));
4992 emit_return_into_block (last
);
4993 epilogue_end
= BB_END (last
);
4994 single_succ_edge (last
)->flags
&= ~EDGE_FALLTHRU
;
4999 /* Find the edge that falls through to EXIT. Other edges may exist
5000 due to RETURN instructions, but those don't need epilogues.
5001 There really shouldn't be a mixture -- either all should have
5002 been converted or none, however... */
5004 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5005 if (e
->flags
& EDGE_FALLTHRU
)
5010 #ifdef HAVE_epilogue
5014 epilogue_end
= emit_note (NOTE_INSN_EPILOGUE_BEG
);
5015 seq
= gen_epilogue ();
5016 emit_jump_insn (seq
);
5018 /* Retain a map of the epilogue insns. */
5019 record_insns (seq
, &epilogue
);
5020 set_insn_locators (seq
, epilogue_locator
);
5025 insert_insn_on_edge (seq
, e
);
5033 if (! next_active_insn (BB_END (e
->src
)))
5035 /* We have a fall-through edge to the exit block, the source is not
5036 at the end of the function, and there will be an assembler epilogue
5037 at the end of the function.
5038 We can't use force_nonfallthru here, because that would try to
5039 use return. Inserting a jump 'by hand' is extremely messy, so
5040 we take advantage of cfg_layout_finalize using
5041 fixup_fallthru_exit_predecessor. */
5042 cfg_layout_initialize (0);
5043 FOR_EACH_BB (cur_bb
)
5044 if (cur_bb
->index
>= NUM_FIXED_BLOCKS
5045 && cur_bb
->next_bb
->index
>= NUM_FIXED_BLOCKS
)
5046 cur_bb
->aux
= cur_bb
->next_bb
;
5047 cfg_layout_finalize ();
5050 default_rtl_profile ();
5054 commit_edge_insertions ();
5056 /* The epilogue insns we inserted may cause the exit edge to no longer
5058 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5060 if (((e
->flags
& EDGE_FALLTHRU
) != 0)
5061 && returnjump_p (BB_END (e
->src
)))
5062 e
->flags
&= ~EDGE_FALLTHRU
;
5066 #ifdef HAVE_sibcall_epilogue
5067 /* Emit sibling epilogues before any sibling call sites. */
5068 for (ei
= ei_start (EXIT_BLOCK_PTR
->preds
); (e
= ei_safe_edge (ei
)); )
5070 basic_block bb
= e
->src
;
5071 rtx insn
= BB_END (bb
);
5074 || ! SIBLING_CALL_P (insn
))
5081 emit_insn (gen_sibcall_epilogue ());
5085 /* Retain a map of the epilogue insns. Used in life analysis to
5086 avoid getting rid of sibcall epilogue insns. Do this before we
5087 actually emit the sequence. */
5088 record_insns (seq
, &sibcall_epilogue
);
5089 set_insn_locators (seq
, epilogue_locator
);
5091 emit_insn_before (seq
, insn
);
5096 #ifdef HAVE_epilogue
5101 /* Similarly, move any line notes that appear after the epilogue.
5102 There is no need, however, to be quite so anal about the existence
5103 of such a note. Also possibly move
5104 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
5106 for (insn
= epilogue_end
; insn
; insn
= next
)
5108 next
= NEXT_INSN (insn
);
5110 && (NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
))
5111 reorder_insns (insn
, insn
, PREV_INSN (epilogue_end
));
5116 /* Threading the prologue and epilogue changes the artificial refs
5117 in the entry and exit blocks. */
5118 epilogue_completed
= 1;
5119 df_update_entry_exit_and_calls ();
5122 /* Reposition the prologue-end and epilogue-begin notes after instruction
5123 scheduling and delayed branch scheduling. */
5126 reposition_prologue_and_epilogue_notes (void)
5128 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
5129 rtx insn
, last
, note
;
5132 if ((len
= VEC_length (int, prologue
)) > 0)
5136 /* Scan from the beginning until we reach the last prologue insn.
5137 We apparently can't depend on basic_block_{head,end} after
5139 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
5143 if (NOTE_KIND (insn
) == NOTE_INSN_PROLOGUE_END
)
5146 else if (contains (insn
, &prologue
))
5156 /* Find the prologue-end note if we haven't already, and
5157 move it to just after the last prologue insn. */
5160 for (note
= last
; (note
= NEXT_INSN (note
));)
5162 && NOTE_KIND (note
) == NOTE_INSN_PROLOGUE_END
)
5166 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
5168 last
= NEXT_INSN (last
);
5169 reorder_insns (note
, note
, last
);
5173 if ((len
= VEC_length (int, epilogue
)) > 0)
5177 /* Scan from the end until we reach the first epilogue insn.
5178 We apparently can't depend on basic_block_{head,end} after
5180 for (insn
= get_last_insn (); insn
; insn
= PREV_INSN (insn
))
5184 if (NOTE_KIND (insn
) == NOTE_INSN_EPILOGUE_BEG
)
5187 else if (contains (insn
, &epilogue
))
5197 /* Find the epilogue-begin note if we haven't already, and
5198 move it to just before the first epilogue insn. */
5201 for (note
= insn
; (note
= PREV_INSN (note
));)
5203 && NOTE_KIND (note
) == NOTE_INSN_EPILOGUE_BEG
)
5207 if (PREV_INSN (last
) != note
)
5208 reorder_insns (note
, note
, PREV_INSN (last
));
5211 #endif /* HAVE_prologue or HAVE_epilogue */
5214 /* Returns the name of the current function. */
5216 current_function_name (void)
5218 return lang_hooks
.decl_printable_name (cfun
->decl
, 2);
5221 /* Returns the raw (mangled) name of the current function. */
5223 current_function_assembler_name (void)
5225 return IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (cfun
->decl
));
5230 rest_of_handle_check_leaf_regs (void)
5232 #ifdef LEAF_REGISTERS
5233 current_function_uses_only_leaf_regs
5234 = optimize
> 0 && only_leaf_regs_used () && leaf_function_p ();
5239 /* Insert a TYPE into the used types hash table of CFUN. */
5241 used_types_insert_helper (tree type
, struct function
*func
)
5243 if (type
!= NULL
&& func
!= NULL
)
5247 if (func
->used_types_hash
== NULL
)
5248 func
->used_types_hash
= htab_create_ggc (37, htab_hash_pointer
,
5249 htab_eq_pointer
, NULL
);
5250 slot
= htab_find_slot (func
->used_types_hash
, type
, INSERT
);
5256 /* Given a type, insert it into the used hash table in cfun. */
5258 used_types_insert (tree t
)
5260 while (POINTER_TYPE_P (t
) || TREE_CODE (t
) == ARRAY_TYPE
)
5262 t
= TYPE_MAIN_VARIANT (t
);
5263 if (debug_info_level
> DINFO_LEVEL_NONE
)
5264 used_types_insert_helper (t
, cfun
);
5267 struct rtl_opt_pass pass_leaf_regs
=
5273 rest_of_handle_check_leaf_regs
, /* execute */
5276 0, /* static_pass_number */
5278 0, /* properties_required */
5279 0, /* properties_provided */
5280 0, /* properties_destroyed */
5281 0, /* todo_flags_start */
5282 0 /* todo_flags_finish */
5287 rest_of_handle_thread_prologue_and_epilogue (void)
5290 cleanup_cfg (CLEANUP_EXPENSIVE
);
5291 /* On some machines, the prologue and epilogue code, or parts thereof,
5292 can be represented as RTL. Doing so lets us schedule insns between
5293 it and the rest of the code and also allows delayed branch
5294 scheduling to operate in the epilogue. */
5296 thread_prologue_and_epilogue_insns ();
5300 struct rtl_opt_pass pass_thread_prologue_and_epilogue
=
5304 "pro_and_epilogue", /* name */
5306 rest_of_handle_thread_prologue_and_epilogue
, /* execute */
5309 0, /* static_pass_number */
5310 TV_THREAD_PROLOGUE_AND_EPILOGUE
, /* tv_id */
5311 0, /* properties_required */
5312 0, /* properties_provided */
5313 0, /* properties_destroyed */
5314 TODO_verify_flow
, /* todo_flags_start */
5317 TODO_df_finish
| TODO_verify_rtl_sharing
|
5318 TODO_ggc_collect
/* todo_flags_finish */
5323 /* This mini-pass fixes fall-out from SSA in asm statements that have
5324 in-out constraints. Say you start with
5327 asm ("": "+mr" (inout));
5330 which is transformed very early to use explicit output and match operands:
5333 asm ("": "=mr" (inout) : "0" (inout));
5336 Or, after SSA and copyprop,
5338 asm ("": "=mr" (inout_2) : "0" (inout_1));
5341 Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
5342 they represent two separate values, so they will get different pseudo
5343 registers during expansion. Then, since the two operands need to match
5344 per the constraints, but use different pseudo registers, reload can
5345 only register a reload for these operands. But reloads can only be
5346 satisfied by hardregs, not by memory, so we need a register for this
5347 reload, just because we are presented with non-matching operands.
5348 So, even though we allow memory for this operand, no memory can be
5349 used for it, just because the two operands don't match. This can
5350 cause reload failures on register-starved targets.
5352 So it's a symptom of reload not being able to use memory for reloads
5353 or, alternatively it's also a symptom of both operands not coming into
5354 reload as matching (in which case the pseudo could go to memory just
5355 fine, as the alternative allows it, and no reload would be necessary).
5356 We fix the latter problem here, by transforming
5358 asm ("": "=mr" (inout_2) : "0" (inout_1));
5363 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
5366 match_asm_constraints_1 (rtx insn
, rtx
*p_sets
, int noutputs
)
5369 bool changed
= false;
5370 rtx op
= SET_SRC (p_sets
[0]);
5371 int ninputs
= ASM_OPERANDS_INPUT_LENGTH (op
);
5372 rtvec inputs
= ASM_OPERANDS_INPUT_VEC (op
);
5373 bool *output_matched
= XALLOCAVEC (bool, noutputs
);
5375 memset (output_matched
, 0, noutputs
* sizeof (bool));
5376 for (i
= 0; i
< ninputs
; i
++)
5378 rtx input
, output
, insns
;
5379 const char *constraint
= ASM_OPERANDS_INPUT_CONSTRAINT (op
, i
);
5383 match
= strtoul (constraint
, &end
, 10);
5384 if (end
== constraint
)
5387 gcc_assert (match
< noutputs
);
5388 output
= SET_DEST (p_sets
[match
]);
5389 input
= RTVEC_ELT (inputs
, i
);
5390 /* Only do the transformation for pseudos. */
5391 if (! REG_P (output
)
5392 || rtx_equal_p (output
, input
)
5393 || (GET_MODE (input
) != VOIDmode
5394 && GET_MODE (input
) != GET_MODE (output
)))
5397 /* We can't do anything if the output is also used as input,
5398 as we're going to overwrite it. */
5399 for (j
= 0; j
< ninputs
; j
++)
5400 if (reg_overlap_mentioned_p (output
, RTVEC_ELT (inputs
, j
)))
5405 /* Avoid changing the same input several times. For
5406 asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
5407 only change in once (to out1), rather than changing it
5408 first to out1 and afterwards to out2. */
5411 for (j
= 0; j
< noutputs
; j
++)
5412 if (output_matched
[j
] && input
== SET_DEST (p_sets
[j
]))
5417 output_matched
[match
] = true;
5420 emit_move_insn (output
, input
);
5421 insns
= get_insns ();
5423 emit_insn_before (insns
, insn
);
5425 /* Now replace all mentions of the input with output. We can't
5426 just replace the occurrence in inputs[i], as the register might
5427 also be used in some other input (or even in an address of an
5428 output), which would mean possibly increasing the number of
5429 inputs by one (namely 'output' in addition), which might pose
5430 a too complicated problem for reload to solve. E.g. this situation:
5432 asm ("" : "=r" (output), "=m" (input) : "0" (input))
5434 Here 'input' is used in two occurrences as input (once for the
5435 input operand, once for the address in the second output operand).
5436 If we would replace only the occurrence of the input operand (to
5437 make the matching) we would be left with this:
5440 asm ("" : "=r" (output), "=m" (input) : "0" (output))
5442 Now we suddenly have two different input values (containing the same
5443 value, but different pseudos) where we formerly had only one.
5444 With more complicated asms this might lead to reload failures
5445 which wouldn't have happen without this pass. So, iterate over
5446 all operands and replace all occurrences of the register used. */
5447 for (j
= 0; j
< noutputs
; j
++)
5448 if (!rtx_equal_p (SET_DEST (p_sets
[j
]), input
)
5449 && reg_overlap_mentioned_p (input
, SET_DEST (p_sets
[j
])))
5450 SET_DEST (p_sets
[j
]) = replace_rtx (SET_DEST (p_sets
[j
]),
5452 for (j
= 0; j
< ninputs
; j
++)
5453 if (reg_overlap_mentioned_p (input
, RTVEC_ELT (inputs
, j
)))
5454 RTVEC_ELT (inputs
, j
) = replace_rtx (RTVEC_ELT (inputs
, j
),
5461 df_insn_rescan (insn
);
5465 rest_of_match_asm_constraints (void)
5468 rtx insn
, pat
, *p_sets
;
5471 if (!crtl
->has_asm_statement
)
5474 df_set_flags (DF_DEFER_INSN_RESCAN
);
5477 FOR_BB_INSNS (bb
, insn
)
5482 pat
= PATTERN (insn
);
5483 if (GET_CODE (pat
) == PARALLEL
)
5484 p_sets
= &XVECEXP (pat
, 0, 0), noutputs
= XVECLEN (pat
, 0);
5485 else if (GET_CODE (pat
) == SET
)
5486 p_sets
= &PATTERN (insn
), noutputs
= 1;
5490 if (GET_CODE (*p_sets
) == SET
5491 && GET_CODE (SET_SRC (*p_sets
)) == ASM_OPERANDS
)
5492 match_asm_constraints_1 (insn
, p_sets
, noutputs
);
5496 return TODO_df_finish
;
5499 struct rtl_opt_pass pass_match_asm_constraints
=
5503 "asmcons", /* name */
5505 rest_of_match_asm_constraints
, /* execute */
5508 0, /* static_pass_number */
5510 0, /* properties_required */
5511 0, /* properties_provided */
5512 0, /* properties_destroyed */
5513 0, /* todo_flags_start */
5514 TODO_dump_func
/* todo_flags_finish */
5519 #include "gt-function.h"