1 /* Expands front end tree to back end RTL for GCC.
2 Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
4 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
22 /* This file handles the generation of rtl code from tree structure
23 at the level of the function as a whole.
24 It creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 `expand_function_start' is called at the beginning of a function,
28 before the function body is parsed, and `expand_function_end' is
29 called after parsing the body.
31 Call `assign_stack_local' to allocate a stack slot for a local variable.
32 This is usually done during the RTL generation for the function body,
33 but it can also be done in the reload pass when a pseudo-register does
34 not get a hard register. */
38 #include "coretypes.h"
49 #include "hard-reg-set.h"
50 #include "insn-config.h"
53 #include "basic-block.h"
58 #include "integrate.h"
59 #include "langhooks.h"
61 #include "cfglayout.h"
62 #include "tree-gimple.h"
63 #include "tree-pass.h"
69 /* So we can assign to cfun in this file. */
72 #ifndef LOCAL_ALIGNMENT
73 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
76 #ifndef STACK_ALIGNMENT_NEEDED
77 #define STACK_ALIGNMENT_NEEDED 1
80 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
82 /* Some systems use __main in a way incompatible with its use in gcc, in these
83 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
84 give the same symbol without quotes for an alternative entry point. You
85 must define both, or neither. */
87 #define NAME__MAIN "__main"
90 /* Round a value to the lowest integer less than it that is a multiple of
91 the required alignment. Avoid using division in case the value is
92 negative. Assume the alignment is a power of two. */
93 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
95 /* Similar, but round to the next highest integer that meets the
97 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
99 /* Nonzero if function being compiled doesn't contain any calls
100 (ignoring the prologue and epilogue). This is set prior to
101 local register allocation and is valid for the remaining
103 int current_function_is_leaf
;
105 /* Nonzero if function being compiled doesn't modify the stack pointer
106 (ignoring the prologue and epilogue). This is only valid after
107 pass_stack_ptr_mod has run. */
108 int current_function_sp_is_unchanging
;
110 /* Nonzero if the function being compiled is a leaf function which only
111 uses leaf registers. This is valid after reload (specifically after
112 sched2) and is useful only if the port defines LEAF_REGISTERS. */
113 int current_function_uses_only_leaf_regs
;
115 /* Nonzero once virtual register instantiation has been done.
116 assign_stack_local uses frame_pointer_rtx when this is nonzero.
117 calls.c:emit_library_call_value_1 uses it to set up
118 post-instantiation libcalls. */
119 int virtuals_instantiated
;
121 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
122 static GTY(()) int funcdef_no
;
124 /* These variables hold pointers to functions to create and destroy
125 target specific, per-function data structures. */
126 struct machine_function
* (*init_machine_status
) (void);
128 /* The currently compiled function. */
129 struct function
*cfun
= 0;
131 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
132 static VEC(int,heap
) *prologue
;
133 static VEC(int,heap
) *epilogue
;
135 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
137 static VEC(int,heap
) *sibcall_epilogue
;
139 /* In order to evaluate some expressions, such as function calls returning
140 structures in memory, we need to temporarily allocate stack locations.
141 We record each allocated temporary in the following structure.
143 Associated with each temporary slot is a nesting level. When we pop up
144 one level, all temporaries associated with the previous level are freed.
145 Normally, all temporaries are freed after the execution of the statement
146 in which they were created. However, if we are inside a ({...}) grouping,
147 the result may be in a temporary and hence must be preserved. If the
148 result could be in a temporary, we preserve it if we can determine which
149 one it is in. If we cannot determine which temporary may contain the
150 result, all temporaries are preserved. A temporary is preserved by
151 pretending it was allocated at the previous nesting level.
153 Automatic variables are also assigned temporary slots, at the nesting
154 level where they are defined. They are marked a "kept" so that
155 free_temp_slots will not free them. */
157 struct temp_slot
GTY(())
159 /* Points to next temporary slot. */
160 struct temp_slot
*next
;
161 /* Points to previous temporary slot. */
162 struct temp_slot
*prev
;
164 /* The rtx to used to reference the slot. */
166 /* The rtx used to represent the address if not the address of the
167 slot above. May be an EXPR_LIST if multiple addresses exist. */
169 /* The alignment (in bits) of the slot. */
171 /* The size, in units, of the slot. */
173 /* The type of the object in the slot, or zero if it doesn't correspond
174 to a type. We use this to determine whether a slot can be reused.
175 It can be reused if objects of the type of the new slot will always
176 conflict with objects of the type of the old slot. */
178 /* Nonzero if this temporary is currently in use. */
180 /* Nonzero if this temporary has its address taken. */
182 /* Nesting level at which this slot is being used. */
184 /* Nonzero if this should survive a call to free_temp_slots. */
186 /* The offset of the slot from the frame_pointer, including extra space
187 for alignment. This info is for combine_temp_slots. */
188 HOST_WIDE_INT base_offset
;
189 /* The size of the slot, including extra space for alignment. This
190 info is for combine_temp_slots. */
191 HOST_WIDE_INT full_size
;
194 /* Forward declarations. */
196 static struct temp_slot
*find_temp_slot_from_address (rtx
);
197 static void pad_to_arg_alignment (struct args_size
*, int, struct args_size
*);
198 static void pad_below (struct args_size
*, enum machine_mode
, tree
);
199 static void reorder_blocks_1 (rtx
, tree
, VEC(tree
,heap
) **);
200 static int all_blocks (tree
, tree
*);
201 static tree
*get_block_vector (tree
, int *);
202 extern tree
debug_find_var_in_block_tree (tree
, tree
);
203 /* We always define `record_insns' even if it's not used so that we
204 can always export `prologue_epilogue_contains'. */
205 static void record_insns (rtx
, VEC(int,heap
) **) ATTRIBUTE_UNUSED
;
206 static int contains (const_rtx
, VEC(int,heap
) **);
208 static void emit_return_into_block (basic_block
);
210 static void prepare_function_start (void);
211 static void do_clobber_return_reg (rtx
, void *);
212 static void do_use_return_reg (rtx
, void *);
213 static void set_insn_locators (rtx
, int) ATTRIBUTE_UNUSED
;
215 /* Pointer to chain of `struct function' for containing functions. */
216 struct function
*outer_function_chain
;
218 /* Given a function decl for a containing function,
219 return the `struct function' for it. */
222 find_function_data (tree decl
)
226 for (p
= outer_function_chain
; p
; p
= p
->outer
)
233 /* Save the current context for compilation of a nested function.
234 This is called from language-specific code. */
237 push_function_context (void)
240 allocate_struct_function (NULL
, false);
242 cfun
->outer
= outer_function_chain
;
243 outer_function_chain
= cfun
;
247 /* Restore the last saved context, at the end of a nested function.
248 This function is called from language-specific code. */
251 pop_function_context (void)
253 struct function
*p
= outer_function_chain
;
256 outer_function_chain
= p
->outer
;
257 current_function_decl
= p
->decl
;
259 /* Reset variables that have known state during rtx generation. */
260 virtuals_instantiated
= 0;
261 generating_concat_p
= 1;
264 /* Clear out all parts of the state in F that can safely be discarded
265 after the function has been parsed, but not compiled, to let
266 garbage collection reclaim the memory. */
269 free_after_parsing (struct function
*f
)
274 /* Clear out all parts of the state in F that can safely be discarded
275 after the function has been compiled, to let garbage collection
276 reclaim the memory. */
279 free_after_compilation (struct function
*f
)
281 VEC_free (int, heap
, prologue
);
282 VEC_free (int, heap
, epilogue
);
283 VEC_free (int, heap
, sibcall_epilogue
);
284 if (crtl
->emit
.regno_pointer_align
)
285 free (crtl
->emit
.regno_pointer_align
);
287 memset (crtl
, 0, sizeof (struct rtl_data
));
292 f
->epilogue_delay_list
= NULL
;
293 regno_reg_rtx
= NULL
;
296 /* Return size needed for stack frame based on slots so far allocated.
297 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
298 the caller may have to do that. */
301 get_frame_size (void)
303 if (FRAME_GROWS_DOWNWARD
)
304 return -frame_offset
;
309 /* Issue an error message and return TRUE if frame OFFSET overflows in
310 the signed target pointer arithmetics for function FUNC. Otherwise
314 frame_offset_overflow (HOST_WIDE_INT offset
, tree func
)
316 unsigned HOST_WIDE_INT size
= FRAME_GROWS_DOWNWARD
? -offset
: offset
;
318 if (size
> ((unsigned HOST_WIDE_INT
) 1 << (GET_MODE_BITSIZE (Pmode
) - 1))
319 /* Leave room for the fixed part of the frame. */
320 - 64 * UNITS_PER_WORD
)
322 error ("%Jtotal size of local objects too large", func
);
329 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
330 with machine mode MODE.
332 ALIGN controls the amount of alignment for the address of the slot:
333 0 means according to MODE,
334 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
335 -2 means use BITS_PER_UNIT,
336 positive specifies alignment boundary in bits.
338 We do not round to stack_boundary here. */
341 assign_stack_local (enum machine_mode mode
, HOST_WIDE_INT size
, int align
)
344 int bigend_correction
= 0;
345 unsigned int alignment
;
346 int frame_off
, frame_alignment
, frame_phase
;
353 alignment
= BIGGEST_ALIGNMENT
;
355 alignment
= GET_MODE_ALIGNMENT (mode
);
357 /* Allow the target to (possibly) increase the alignment of this
359 type
= lang_hooks
.types
.type_for_mode (mode
, 0);
361 alignment
= LOCAL_ALIGNMENT (type
, alignment
);
363 alignment
/= BITS_PER_UNIT
;
365 else if (align
== -1)
367 alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
368 size
= CEIL_ROUND (size
, alignment
);
370 else if (align
== -2)
371 alignment
= 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
373 alignment
= align
/ BITS_PER_UNIT
;
375 if (FRAME_GROWS_DOWNWARD
)
376 frame_offset
-= size
;
378 /* Ignore alignment we can't do with expected alignment of the boundary. */
379 if (alignment
* BITS_PER_UNIT
> PREFERRED_STACK_BOUNDARY
)
380 alignment
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
382 if (cfun
->stack_alignment_needed
< alignment
* BITS_PER_UNIT
)
383 cfun
->stack_alignment_needed
= alignment
* BITS_PER_UNIT
;
385 /* Calculate how many bytes the start of local variables is off from
387 frame_alignment
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
388 frame_off
= STARTING_FRAME_OFFSET
% frame_alignment
;
389 frame_phase
= frame_off
? frame_alignment
- frame_off
: 0;
391 /* Round the frame offset to the specified alignment. The default is
392 to always honor requests to align the stack but a port may choose to
393 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
394 if (STACK_ALIGNMENT_NEEDED
398 /* We must be careful here, since FRAME_OFFSET might be negative and
399 division with a negative dividend isn't as well defined as we might
400 like. So we instead assume that ALIGNMENT is a power of two and
401 use logical operations which are unambiguous. */
402 if (FRAME_GROWS_DOWNWARD
)
404 = (FLOOR_ROUND (frame_offset
- frame_phase
,
405 (unsigned HOST_WIDE_INT
) alignment
)
409 = (CEIL_ROUND (frame_offset
- frame_phase
,
410 (unsigned HOST_WIDE_INT
) alignment
)
414 /* On a big-endian machine, if we are allocating more space than we will use,
415 use the least significant bytes of those that are allocated. */
416 if (BYTES_BIG_ENDIAN
&& mode
!= BLKmode
&& GET_MODE_SIZE (mode
) < size
)
417 bigend_correction
= size
- GET_MODE_SIZE (mode
);
419 /* If we have already instantiated virtual registers, return the actual
420 address relative to the frame pointer. */
421 if (virtuals_instantiated
)
422 addr
= plus_constant (frame_pointer_rtx
,
424 (frame_offset
+ bigend_correction
425 + STARTING_FRAME_OFFSET
, Pmode
));
427 addr
= plus_constant (virtual_stack_vars_rtx
,
429 (frame_offset
+ bigend_correction
,
432 if (!FRAME_GROWS_DOWNWARD
)
433 frame_offset
+= size
;
435 x
= gen_rtx_MEM (mode
, addr
);
436 MEM_NOTRAP_P (x
) = 1;
439 = gen_rtx_EXPR_LIST (VOIDmode
, x
, stack_slot_list
);
441 if (frame_offset_overflow (frame_offset
, current_function_decl
))
447 /* Removes temporary slot TEMP from LIST. */
450 cut_slot_from_list (struct temp_slot
*temp
, struct temp_slot
**list
)
453 temp
->next
->prev
= temp
->prev
;
455 temp
->prev
->next
= temp
->next
;
459 temp
->prev
= temp
->next
= NULL
;
462 /* Inserts temporary slot TEMP to LIST. */
465 insert_slot_to_list (struct temp_slot
*temp
, struct temp_slot
**list
)
469 (*list
)->prev
= temp
;
474 /* Returns the list of used temp slots at LEVEL. */
476 static struct temp_slot
**
477 temp_slots_at_level (int level
)
479 if (level
>= (int) VEC_length (temp_slot_p
, used_temp_slots
))
480 VEC_safe_grow_cleared (temp_slot_p
, gc
, used_temp_slots
, level
+ 1);
482 return &(VEC_address (temp_slot_p
, used_temp_slots
)[level
]);
485 /* Returns the maximal temporary slot level. */
488 max_slot_level (void)
490 if (!used_temp_slots
)
493 return VEC_length (temp_slot_p
, used_temp_slots
) - 1;
496 /* Moves temporary slot TEMP to LEVEL. */
499 move_slot_to_level (struct temp_slot
*temp
, int level
)
501 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
502 insert_slot_to_list (temp
, temp_slots_at_level (level
));
506 /* Make temporary slot TEMP available. */
509 make_slot_available (struct temp_slot
*temp
)
511 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
512 insert_slot_to_list (temp
, &avail_temp_slots
);
517 /* Allocate a temporary stack slot and record it for possible later
520 MODE is the machine mode to be given to the returned rtx.
522 SIZE is the size in units of the space required. We do no rounding here
523 since assign_stack_local will do any required rounding.
525 KEEP is 1 if this slot is to be retained after a call to
526 free_temp_slots. Automatic variables for a block are allocated
527 with this flag. KEEP values of 2 or 3 were needed respectively
528 for variables whose lifetime is controlled by CLEANUP_POINT_EXPRs
529 or for SAVE_EXPRs, but they are now unused.
531 TYPE is the type that will be used for the stack slot. */
534 assign_stack_temp_for_type (enum machine_mode mode
, HOST_WIDE_INT size
,
538 struct temp_slot
*p
, *best_p
= 0, *selected
= NULL
, **pp
;
541 /* If SIZE is -1 it means that somebody tried to allocate a temporary
542 of a variable size. */
543 gcc_assert (size
!= -1);
545 /* These are now unused. */
546 gcc_assert (keep
<= 1);
549 align
= BIGGEST_ALIGNMENT
;
551 align
= GET_MODE_ALIGNMENT (mode
);
554 type
= lang_hooks
.types
.type_for_mode (mode
, 0);
557 align
= LOCAL_ALIGNMENT (type
, align
);
559 /* Try to find an available, already-allocated temporary of the proper
560 mode which meets the size and alignment requirements. Choose the
561 smallest one with the closest alignment.
563 If assign_stack_temp is called outside of the tree->rtl expansion,
564 we cannot reuse the stack slots (that may still refer to
565 VIRTUAL_STACK_VARS_REGNUM). */
566 if (!virtuals_instantiated
)
568 for (p
= avail_temp_slots
; p
; p
= p
->next
)
570 if (p
->align
>= align
&& p
->size
>= size
571 && GET_MODE (p
->slot
) == mode
572 && objects_must_conflict_p (p
->type
, type
)
573 && (best_p
== 0 || best_p
->size
> p
->size
574 || (best_p
->size
== p
->size
&& best_p
->align
> p
->align
)))
576 if (p
->align
== align
&& p
->size
== size
)
579 cut_slot_from_list (selected
, &avail_temp_slots
);
588 /* Make our best, if any, the one to use. */
592 cut_slot_from_list (selected
, &avail_temp_slots
);
594 /* If there are enough aligned bytes left over, make them into a new
595 temp_slot so that the extra bytes don't get wasted. Do this only
596 for BLKmode slots, so that we can be sure of the alignment. */
597 if (GET_MODE (best_p
->slot
) == BLKmode
)
599 int alignment
= best_p
->align
/ BITS_PER_UNIT
;
600 HOST_WIDE_INT rounded_size
= CEIL_ROUND (size
, alignment
);
602 if (best_p
->size
- rounded_size
>= alignment
)
604 p
= ggc_alloc (sizeof (struct temp_slot
));
605 p
->in_use
= p
->addr_taken
= 0;
606 p
->size
= best_p
->size
- rounded_size
;
607 p
->base_offset
= best_p
->base_offset
+ rounded_size
;
608 p
->full_size
= best_p
->full_size
- rounded_size
;
609 p
->slot
= adjust_address_nv (best_p
->slot
, BLKmode
, rounded_size
);
610 p
->align
= best_p
->align
;
612 p
->type
= best_p
->type
;
613 insert_slot_to_list (p
, &avail_temp_slots
);
615 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, p
->slot
,
618 best_p
->size
= rounded_size
;
619 best_p
->full_size
= rounded_size
;
624 /* If we still didn't find one, make a new temporary. */
627 HOST_WIDE_INT frame_offset_old
= frame_offset
;
629 p
= ggc_alloc (sizeof (struct temp_slot
));
631 /* We are passing an explicit alignment request to assign_stack_local.
632 One side effect of that is assign_stack_local will not round SIZE
633 to ensure the frame offset remains suitably aligned.
635 So for requests which depended on the rounding of SIZE, we go ahead
636 and round it now. We also make sure ALIGNMENT is at least
637 BIGGEST_ALIGNMENT. */
638 gcc_assert (mode
!= BLKmode
|| align
== BIGGEST_ALIGNMENT
);
639 p
->slot
= assign_stack_local (mode
,
641 ? CEIL_ROUND (size
, (int) align
/ BITS_PER_UNIT
)
647 /* The following slot size computation is necessary because we don't
648 know the actual size of the temporary slot until assign_stack_local
649 has performed all the frame alignment and size rounding for the
650 requested temporary. Note that extra space added for alignment
651 can be either above or below this stack slot depending on which
652 way the frame grows. We include the extra space if and only if it
653 is above this slot. */
654 if (FRAME_GROWS_DOWNWARD
)
655 p
->size
= frame_offset_old
- frame_offset
;
659 /* Now define the fields used by combine_temp_slots. */
660 if (FRAME_GROWS_DOWNWARD
)
662 p
->base_offset
= frame_offset
;
663 p
->full_size
= frame_offset_old
- frame_offset
;
667 p
->base_offset
= frame_offset_old
;
668 p
->full_size
= frame_offset
- frame_offset_old
;
679 p
->level
= temp_slot_level
;
682 pp
= temp_slots_at_level (p
->level
);
683 insert_slot_to_list (p
, pp
);
685 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
686 slot
= gen_rtx_MEM (mode
, XEXP (p
->slot
, 0));
687 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, slot
, stack_slot_list
);
689 /* If we know the alias set for the memory that will be used, use
690 it. If there's no TYPE, then we don't know anything about the
691 alias set for the memory. */
692 set_mem_alias_set (slot
, type
? get_alias_set (type
) : 0);
693 set_mem_align (slot
, align
);
695 /* If a type is specified, set the relevant flags. */
698 MEM_VOLATILE_P (slot
) = TYPE_VOLATILE (type
);
699 MEM_SET_IN_STRUCT_P (slot
, (AGGREGATE_TYPE_P (type
)
700 || TREE_CODE (type
) == COMPLEX_TYPE
));
702 MEM_NOTRAP_P (slot
) = 1;
707 /* Allocate a temporary stack slot and record it for possible later
708 reuse. First three arguments are same as in preceding function. */
711 assign_stack_temp (enum machine_mode mode
, HOST_WIDE_INT size
, int keep
)
713 return assign_stack_temp_for_type (mode
, size
, keep
, NULL_TREE
);
716 /* Assign a temporary.
717 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
718 and so that should be used in error messages. In either case, we
719 allocate of the given type.
720 KEEP is as for assign_stack_temp.
721 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
722 it is 0 if a register is OK.
723 DONT_PROMOTE is 1 if we should not promote values in register
727 assign_temp (tree type_or_decl
, int keep
, int memory_required
,
728 int dont_promote ATTRIBUTE_UNUSED
)
731 enum machine_mode mode
;
736 if (DECL_P (type_or_decl
))
737 decl
= type_or_decl
, type
= TREE_TYPE (decl
);
739 decl
= NULL
, type
= type_or_decl
;
741 mode
= TYPE_MODE (type
);
743 unsignedp
= TYPE_UNSIGNED (type
);
746 if (mode
== BLKmode
|| memory_required
)
748 HOST_WIDE_INT size
= int_size_in_bytes (type
);
751 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
752 problems with allocating the stack space. */
756 /* Unfortunately, we don't yet know how to allocate variable-sized
757 temporaries. However, sometimes we can find a fixed upper limit on
758 the size, so try that instead. */
760 size
= max_int_size_in_bytes (type
);
762 /* The size of the temporary may be too large to fit into an integer. */
763 /* ??? Not sure this should happen except for user silliness, so limit
764 this to things that aren't compiler-generated temporaries. The
765 rest of the time we'll die in assign_stack_temp_for_type. */
766 if (decl
&& size
== -1
767 && TREE_CODE (TYPE_SIZE_UNIT (type
)) == INTEGER_CST
)
769 error ("size of variable %q+D is too large", decl
);
773 tmp
= assign_stack_temp_for_type (mode
, size
, keep
, type
);
779 mode
= promote_mode (type
, mode
, &unsignedp
, 0);
782 return gen_reg_rtx (mode
);
785 /* Combine temporary stack slots which are adjacent on the stack.
787 This allows for better use of already allocated stack space. This is only
788 done for BLKmode slots because we can be sure that we won't have alignment
789 problems in this case. */
792 combine_temp_slots (void)
794 struct temp_slot
*p
, *q
, *next
, *next_q
;
797 /* We can't combine slots, because the information about which slot
798 is in which alias set will be lost. */
799 if (flag_strict_aliasing
)
802 /* If there are a lot of temp slots, don't do anything unless
803 high levels of optimization. */
804 if (! flag_expensive_optimizations
)
805 for (p
= avail_temp_slots
, num_slots
= 0; p
; p
= p
->next
, num_slots
++)
806 if (num_slots
> 100 || (num_slots
> 10 && optimize
== 0))
809 for (p
= avail_temp_slots
; p
; p
= next
)
815 if (GET_MODE (p
->slot
) != BLKmode
)
818 for (q
= p
->next
; q
; q
= next_q
)
824 if (GET_MODE (q
->slot
) != BLKmode
)
827 if (p
->base_offset
+ p
->full_size
== q
->base_offset
)
829 /* Q comes after P; combine Q into P. */
831 p
->full_size
+= q
->full_size
;
834 else if (q
->base_offset
+ q
->full_size
== p
->base_offset
)
836 /* P comes after Q; combine P into Q. */
838 q
->full_size
+= p
->full_size
;
843 cut_slot_from_list (q
, &avail_temp_slots
);
846 /* Either delete P or advance past it. */
848 cut_slot_from_list (p
, &avail_temp_slots
);
852 /* Find the temp slot corresponding to the object at address X. */
854 static struct temp_slot
*
855 find_temp_slot_from_address (rtx x
)
861 for (i
= max_slot_level (); i
>= 0; i
--)
862 for (p
= *temp_slots_at_level (i
); p
; p
= p
->next
)
864 if (XEXP (p
->slot
, 0) == x
866 || (GET_CODE (x
) == PLUS
867 && XEXP (x
, 0) == virtual_stack_vars_rtx
868 && GET_CODE (XEXP (x
, 1)) == CONST_INT
869 && INTVAL (XEXP (x
, 1)) >= p
->base_offset
870 && INTVAL (XEXP (x
, 1)) < p
->base_offset
+ p
->full_size
))
873 else if (p
->address
!= 0 && GET_CODE (p
->address
) == EXPR_LIST
)
874 for (next
= p
->address
; next
; next
= XEXP (next
, 1))
875 if (XEXP (next
, 0) == x
)
879 /* If we have a sum involving a register, see if it points to a temp
881 if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 0))
882 && (p
= find_temp_slot_from_address (XEXP (x
, 0))) != 0)
884 else if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 1))
885 && (p
= find_temp_slot_from_address (XEXP (x
, 1))) != 0)
891 /* Indicate that NEW is an alternate way of referring to the temp slot
892 that previously was known by OLD. */
895 update_temp_slot_address (rtx old
, rtx
new)
899 if (rtx_equal_p (old
, new))
902 p
= find_temp_slot_from_address (old
);
904 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
905 is a register, see if one operand of the PLUS is a temporary
906 location. If so, NEW points into it. Otherwise, if both OLD and
907 NEW are a PLUS and if there is a register in common between them.
908 If so, try a recursive call on those values. */
911 if (GET_CODE (old
) != PLUS
)
916 update_temp_slot_address (XEXP (old
, 0), new);
917 update_temp_slot_address (XEXP (old
, 1), new);
920 else if (GET_CODE (new) != PLUS
)
923 if (rtx_equal_p (XEXP (old
, 0), XEXP (new, 0)))
924 update_temp_slot_address (XEXP (old
, 1), XEXP (new, 1));
925 else if (rtx_equal_p (XEXP (old
, 1), XEXP (new, 0)))
926 update_temp_slot_address (XEXP (old
, 0), XEXP (new, 1));
927 else if (rtx_equal_p (XEXP (old
, 0), XEXP (new, 1)))
928 update_temp_slot_address (XEXP (old
, 1), XEXP (new, 0));
929 else if (rtx_equal_p (XEXP (old
, 1), XEXP (new, 1)))
930 update_temp_slot_address (XEXP (old
, 0), XEXP (new, 0));
935 /* Otherwise add an alias for the temp's address. */
936 else if (p
->address
== 0)
940 if (GET_CODE (p
->address
) != EXPR_LIST
)
941 p
->address
= gen_rtx_EXPR_LIST (VOIDmode
, p
->address
, NULL_RTX
);
943 p
->address
= gen_rtx_EXPR_LIST (VOIDmode
, new, p
->address
);
947 /* If X could be a reference to a temporary slot, mark the fact that its
948 address was taken. */
951 mark_temp_addr_taken (rtx x
)
958 /* If X is not in memory or is at a constant address, it cannot be in
960 if (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0)))
963 p
= find_temp_slot_from_address (XEXP (x
, 0));
968 /* If X could be a reference to a temporary slot, mark that slot as
969 belonging to the to one level higher than the current level. If X
970 matched one of our slots, just mark that one. Otherwise, we can't
971 easily predict which it is, so upgrade all of them. Kept slots
974 This is called when an ({...}) construct occurs and a statement
975 returns a value in memory. */
978 preserve_temp_slots (rtx x
)
980 struct temp_slot
*p
= 0, *next
;
982 /* If there is no result, we still might have some objects whose address
983 were taken, so we need to make sure they stay around. */
986 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
991 move_slot_to_level (p
, temp_slot_level
- 1);
997 /* If X is a register that is being used as a pointer, see if we have
998 a temporary slot we know it points to. To be consistent with
999 the code below, we really should preserve all non-kept slots
1000 if we can't find a match, but that seems to be much too costly. */
1001 if (REG_P (x
) && REG_POINTER (x
))
1002 p
= find_temp_slot_from_address (x
);
1004 /* If X is not in memory or is at a constant address, it cannot be in
1005 a temporary slot, but it can contain something whose address was
1007 if (p
== 0 && (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0))))
1009 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1014 move_slot_to_level (p
, temp_slot_level
- 1);
1020 /* First see if we can find a match. */
1022 p
= find_temp_slot_from_address (XEXP (x
, 0));
1026 /* Move everything at our level whose address was taken to our new
1027 level in case we used its address. */
1028 struct temp_slot
*q
;
1030 if (p
->level
== temp_slot_level
)
1032 for (q
= *temp_slots_at_level (temp_slot_level
); q
; q
= next
)
1036 if (p
!= q
&& q
->addr_taken
)
1037 move_slot_to_level (q
, temp_slot_level
- 1);
1040 move_slot_to_level (p
, temp_slot_level
- 1);
1046 /* Otherwise, preserve all non-kept slots at this level. */
1047 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1052 move_slot_to_level (p
, temp_slot_level
- 1);
1056 /* Free all temporaries used so far. This is normally called at the
1057 end of generating code for a statement. */
1060 free_temp_slots (void)
1062 struct temp_slot
*p
, *next
;
1064 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1069 make_slot_available (p
);
1072 combine_temp_slots ();
1075 /* Push deeper into the nesting level for stack temporaries. */
1078 push_temp_slots (void)
1083 /* Pop a temporary nesting level. All slots in use in the current level
1087 pop_temp_slots (void)
1089 struct temp_slot
*p
, *next
;
1091 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1094 make_slot_available (p
);
1097 combine_temp_slots ();
1102 /* Initialize temporary slots. */
1105 init_temp_slots (void)
1107 /* We have not allocated any temporaries yet. */
1108 avail_temp_slots
= 0;
1109 used_temp_slots
= 0;
1110 temp_slot_level
= 0;
1113 /* These routines are responsible for converting virtual register references
1114 to the actual hard register references once RTL generation is complete.
1116 The following four variables are used for communication between the
1117 routines. They contain the offsets of the virtual registers from their
1118 respective hard registers. */
1120 static int in_arg_offset
;
1121 static int var_offset
;
1122 static int dynamic_offset
;
1123 static int out_arg_offset
;
1124 static int cfa_offset
;
1126 /* In most machines, the stack pointer register is equivalent to the bottom
1129 #ifndef STACK_POINTER_OFFSET
1130 #define STACK_POINTER_OFFSET 0
1133 /* If not defined, pick an appropriate default for the offset of dynamically
1134 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1135 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1137 #ifndef STACK_DYNAMIC_OFFSET
1139 /* The bottom of the stack points to the actual arguments. If
1140 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1141 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1142 stack space for register parameters is not pushed by the caller, but
1143 rather part of the fixed stack areas and hence not included in
1144 `crtl->outgoing_args_size'. Nevertheless, we must allow
1145 for it when allocating stack dynamic objects. */
1147 #if defined(REG_PARM_STACK_SPACE)
1148 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1149 ((ACCUMULATE_OUTGOING_ARGS \
1150 ? (crtl->outgoing_args_size \
1151 + (OUTGOING_REG_PARM_STACK_SPACE ? 0 : REG_PARM_STACK_SPACE (FNDECL))) \
1152 : 0) + (STACK_POINTER_OFFSET))
1154 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1155 ((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : 0) \
1156 + (STACK_POINTER_OFFSET))
1161 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1162 is a virtual register, return the equivalent hard register and set the
1163 offset indirectly through the pointer. Otherwise, return 0. */
1166 instantiate_new_reg (rtx x
, HOST_WIDE_INT
*poffset
)
1169 HOST_WIDE_INT offset
;
1171 if (x
== virtual_incoming_args_rtx
)
1172 new = arg_pointer_rtx
, offset
= in_arg_offset
;
1173 else if (x
== virtual_stack_vars_rtx
)
1174 new = frame_pointer_rtx
, offset
= var_offset
;
1175 else if (x
== virtual_stack_dynamic_rtx
)
1176 new = stack_pointer_rtx
, offset
= dynamic_offset
;
1177 else if (x
== virtual_outgoing_args_rtx
)
1178 new = stack_pointer_rtx
, offset
= out_arg_offset
;
1179 else if (x
== virtual_cfa_rtx
)
1181 #ifdef FRAME_POINTER_CFA_OFFSET
1182 new = frame_pointer_rtx
;
1184 new = arg_pointer_rtx
;
1186 offset
= cfa_offset
;
1195 /* A subroutine of instantiate_virtual_regs, called via for_each_rtx.
1196 Instantiate any virtual registers present inside of *LOC. The expression
1197 is simplified, as much as possible, but is not to be considered "valid"
1198 in any sense implied by the target. If any change is made, set CHANGED
1202 instantiate_virtual_regs_in_rtx (rtx
*loc
, void *data
)
1204 HOST_WIDE_INT offset
;
1205 bool *changed
= (bool *) data
;
1212 switch (GET_CODE (x
))
1215 new = instantiate_new_reg (x
, &offset
);
1218 *loc
= plus_constant (new, offset
);
1225 new = instantiate_new_reg (XEXP (x
, 0), &offset
);
1228 new = plus_constant (new, offset
);
1229 *loc
= simplify_gen_binary (PLUS
, GET_MODE (x
), new, XEXP (x
, 1));
1235 /* FIXME -- from old code */
1236 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1237 we can commute the PLUS and SUBREG because pointers into the
1238 frame are well-behaved. */
1248 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1249 matches the predicate for insn CODE operand OPERAND. */
1252 safe_insn_predicate (int code
, int operand
, rtx x
)
1254 const struct insn_operand_data
*op_data
;
1259 op_data
= &insn_data
[code
].operand
[operand
];
1260 if (op_data
->predicate
== NULL
)
1263 return op_data
->predicate (x
, op_data
->mode
);
1266 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1267 registers present inside of insn. The result will be a valid insn. */
1270 instantiate_virtual_regs_in_insn (rtx insn
)
1272 HOST_WIDE_INT offset
;
1274 bool any_change
= false;
1275 rtx set
, new, x
, seq
;
1277 /* There are some special cases to be handled first. */
1278 set
= single_set (insn
);
1281 /* We're allowed to assign to a virtual register. This is interpreted
1282 to mean that the underlying register gets assigned the inverse
1283 transformation. This is used, for example, in the handling of
1285 new = instantiate_new_reg (SET_DEST (set
), &offset
);
1290 for_each_rtx (&SET_SRC (set
), instantiate_virtual_regs_in_rtx
, NULL
);
1291 x
= simplify_gen_binary (PLUS
, GET_MODE (new), SET_SRC (set
),
1293 x
= force_operand (x
, new);
1295 emit_move_insn (new, x
);
1300 emit_insn_before (seq
, insn
);
1305 /* Handle a straight copy from a virtual register by generating a
1306 new add insn. The difference between this and falling through
1307 to the generic case is avoiding a new pseudo and eliminating a
1308 move insn in the initial rtl stream. */
1309 new = instantiate_new_reg (SET_SRC (set
), &offset
);
1310 if (new && offset
!= 0
1311 && REG_P (SET_DEST (set
))
1312 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1316 x
= expand_simple_binop (GET_MODE (SET_DEST (set
)), PLUS
,
1317 new, GEN_INT (offset
), SET_DEST (set
),
1318 1, OPTAB_LIB_WIDEN
);
1319 if (x
!= SET_DEST (set
))
1320 emit_move_insn (SET_DEST (set
), x
);
1325 emit_insn_before (seq
, insn
);
1330 extract_insn (insn
);
1331 insn_code
= INSN_CODE (insn
);
1333 /* Handle a plus involving a virtual register by determining if the
1334 operands remain valid if they're modified in place. */
1335 if (GET_CODE (SET_SRC (set
)) == PLUS
1336 && recog_data
.n_operands
>= 3
1337 && recog_data
.operand_loc
[1] == &XEXP (SET_SRC (set
), 0)
1338 && recog_data
.operand_loc
[2] == &XEXP (SET_SRC (set
), 1)
1339 && GET_CODE (recog_data
.operand
[2]) == CONST_INT
1340 && (new = instantiate_new_reg (recog_data
.operand
[1], &offset
)))
1342 offset
+= INTVAL (recog_data
.operand
[2]);
1344 /* If the sum is zero, then replace with a plain move. */
1346 && REG_P (SET_DEST (set
))
1347 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1350 emit_move_insn (SET_DEST (set
), new);
1354 emit_insn_before (seq
, insn
);
1359 x
= gen_int_mode (offset
, recog_data
.operand_mode
[2]);
1361 /* Using validate_change and apply_change_group here leaves
1362 recog_data in an invalid state. Since we know exactly what
1363 we want to check, do those two by hand. */
1364 if (safe_insn_predicate (insn_code
, 1, new)
1365 && safe_insn_predicate (insn_code
, 2, x
))
1367 *recog_data
.operand_loc
[1] = recog_data
.operand
[1] = new;
1368 *recog_data
.operand_loc
[2] = recog_data
.operand
[2] = x
;
1371 /* Fall through into the regular operand fixup loop in
1372 order to take care of operands other than 1 and 2. */
1378 extract_insn (insn
);
1379 insn_code
= INSN_CODE (insn
);
1382 /* In the general case, we expect virtual registers to appear only in
1383 operands, and then only as either bare registers or inside memories. */
1384 for (i
= 0; i
< recog_data
.n_operands
; ++i
)
1386 x
= recog_data
.operand
[i
];
1387 switch (GET_CODE (x
))
1391 rtx addr
= XEXP (x
, 0);
1392 bool changed
= false;
1394 for_each_rtx (&addr
, instantiate_virtual_regs_in_rtx
, &changed
);
1399 x
= replace_equiv_address (x
, addr
);
1400 /* It may happen that the address with the virtual reg
1401 was valid (e.g. based on the virtual stack reg, which might
1402 be acceptable to the predicates with all offsets), whereas
1403 the address now isn't anymore, for instance when the address
1404 is still offsetted, but the base reg isn't virtual-stack-reg
1405 anymore. Below we would do a force_reg on the whole operand,
1406 but this insn might actually only accept memory. Hence,
1407 before doing that last resort, try to reload the address into
1408 a register, so this operand stays a MEM. */
1409 if (!safe_insn_predicate (insn_code
, i
, x
))
1411 addr
= force_reg (GET_MODE (addr
), addr
);
1412 x
= replace_equiv_address (x
, addr
);
1417 emit_insn_before (seq
, insn
);
1422 new = instantiate_new_reg (x
, &offset
);
1431 /* Careful, special mode predicates may have stuff in
1432 insn_data[insn_code].operand[i].mode that isn't useful
1433 to us for computing a new value. */
1434 /* ??? Recognize address_operand and/or "p" constraints
1435 to see if (plus new offset) is a valid before we put
1436 this through expand_simple_binop. */
1437 x
= expand_simple_binop (GET_MODE (x
), PLUS
, new,
1438 GEN_INT (offset
), NULL_RTX
,
1439 1, OPTAB_LIB_WIDEN
);
1442 emit_insn_before (seq
, insn
);
1447 new = instantiate_new_reg (SUBREG_REG (x
), &offset
);
1453 new = expand_simple_binop (GET_MODE (new), PLUS
, new,
1454 GEN_INT (offset
), NULL_RTX
,
1455 1, OPTAB_LIB_WIDEN
);
1458 emit_insn_before (seq
, insn
);
1460 x
= simplify_gen_subreg (recog_data
.operand_mode
[i
], new,
1461 GET_MODE (new), SUBREG_BYTE (x
));
1468 /* At this point, X contains the new value for the operand.
1469 Validate the new value vs the insn predicate. Note that
1470 asm insns will have insn_code -1 here. */
1471 if (!safe_insn_predicate (insn_code
, i
, x
))
1474 x
= force_reg (insn_data
[insn_code
].operand
[i
].mode
, x
);
1478 emit_insn_before (seq
, insn
);
1481 *recog_data
.operand_loc
[i
] = recog_data
.operand
[i
] = x
;
1487 /* Propagate operand changes into the duplicates. */
1488 for (i
= 0; i
< recog_data
.n_dups
; ++i
)
1489 *recog_data
.dup_loc
[i
]
1490 = copy_rtx (recog_data
.operand
[(unsigned)recog_data
.dup_num
[i
]]);
1492 /* Force re-recognition of the instruction for validation. */
1493 INSN_CODE (insn
) = -1;
1496 if (asm_noperands (PATTERN (insn
)) >= 0)
1498 if (!check_asm_operands (PATTERN (insn
)))
1500 error_for_asm (insn
, "impossible constraint in %<asm%>");
1506 if (recog_memoized (insn
) < 0)
1507 fatal_insn_not_found (insn
);
1511 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1512 do any instantiation required. */
1515 instantiate_decl_rtl (rtx x
)
1522 /* If this is a CONCAT, recurse for the pieces. */
1523 if (GET_CODE (x
) == CONCAT
)
1525 instantiate_decl_rtl (XEXP (x
, 0));
1526 instantiate_decl_rtl (XEXP (x
, 1));
1530 /* If this is not a MEM, no need to do anything. Similarly if the
1531 address is a constant or a register that is not a virtual register. */
1536 if (CONSTANT_P (addr
)
1538 && (REGNO (addr
) < FIRST_VIRTUAL_REGISTER
1539 || REGNO (addr
) > LAST_VIRTUAL_REGISTER
)))
1542 for_each_rtx (&XEXP (x
, 0), instantiate_virtual_regs_in_rtx
, NULL
);
1545 /* Helper for instantiate_decls called via walk_tree: Process all decls
1546 in the given DECL_VALUE_EXPR. */
1549 instantiate_expr (tree
*tp
, int *walk_subtrees
, void *data ATTRIBUTE_UNUSED
)
1552 if (! EXPR_P (t
) && ! GIMPLE_STMT_P (t
))
1555 if (DECL_P (t
) && DECL_RTL_SET_P (t
))
1556 instantiate_decl_rtl (DECL_RTL (t
));
1561 /* Subroutine of instantiate_decls: Process all decls in the given
1562 BLOCK node and all its subblocks. */
1565 instantiate_decls_1 (tree let
)
1569 for (t
= BLOCK_VARS (let
); t
; t
= TREE_CHAIN (t
))
1571 if (DECL_RTL_SET_P (t
))
1572 instantiate_decl_rtl (DECL_RTL (t
));
1573 if (TREE_CODE (t
) == VAR_DECL
&& DECL_HAS_VALUE_EXPR_P (t
))
1575 tree v
= DECL_VALUE_EXPR (t
);
1576 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1580 /* Process all subblocks. */
1581 for (t
= BLOCK_SUBBLOCKS (let
); t
; t
= BLOCK_CHAIN (t
))
1582 instantiate_decls_1 (t
);
1585 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1586 all virtual registers in their DECL_RTL's. */
1589 instantiate_decls (tree fndecl
)
1593 /* Process all parameters of the function. */
1594 for (decl
= DECL_ARGUMENTS (fndecl
); decl
; decl
= TREE_CHAIN (decl
))
1596 instantiate_decl_rtl (DECL_RTL (decl
));
1597 instantiate_decl_rtl (DECL_INCOMING_RTL (decl
));
1598 if (DECL_HAS_VALUE_EXPR_P (decl
))
1600 tree v
= DECL_VALUE_EXPR (decl
);
1601 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1605 /* Now process all variables defined in the function or its subblocks. */
1606 instantiate_decls_1 (DECL_INITIAL (fndecl
));
1609 /* Pass through the INSNS of function FNDECL and convert virtual register
1610 references to hard register references. */
1613 instantiate_virtual_regs (void)
1617 /* Compute the offsets to use for this function. */
1618 in_arg_offset
= FIRST_PARM_OFFSET (current_function_decl
);
1619 var_offset
= STARTING_FRAME_OFFSET
;
1620 dynamic_offset
= STACK_DYNAMIC_OFFSET (current_function_decl
);
1621 out_arg_offset
= STACK_POINTER_OFFSET
;
1622 #ifdef FRAME_POINTER_CFA_OFFSET
1623 cfa_offset
= FRAME_POINTER_CFA_OFFSET (current_function_decl
);
1625 cfa_offset
= ARG_POINTER_CFA_OFFSET (current_function_decl
);
1628 /* Initialize recognition, indicating that volatile is OK. */
1631 /* Scan through all the insns, instantiating every virtual register still
1633 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
1636 /* These patterns in the instruction stream can never be recognized.
1637 Fortunately, they shouldn't contain virtual registers either. */
1638 if (GET_CODE (PATTERN (insn
)) == USE
1639 || GET_CODE (PATTERN (insn
)) == CLOBBER
1640 || GET_CODE (PATTERN (insn
)) == ADDR_VEC
1641 || GET_CODE (PATTERN (insn
)) == ADDR_DIFF_VEC
1642 || GET_CODE (PATTERN (insn
)) == ASM_INPUT
)
1645 instantiate_virtual_regs_in_insn (insn
);
1647 if (INSN_DELETED_P (insn
))
1650 for_each_rtx (®_NOTES (insn
), instantiate_virtual_regs_in_rtx
, NULL
);
1652 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1653 if (GET_CODE (insn
) == CALL_INSN
)
1654 for_each_rtx (&CALL_INSN_FUNCTION_USAGE (insn
),
1655 instantiate_virtual_regs_in_rtx
, NULL
);
1658 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1659 instantiate_decls (current_function_decl
);
1661 targetm
.instantiate_decls ();
1663 /* Indicate that, from now on, assign_stack_local should use
1664 frame_pointer_rtx. */
1665 virtuals_instantiated
= 1;
1669 struct rtl_opt_pass pass_instantiate_virtual_regs
=
1675 instantiate_virtual_regs
, /* execute */
1678 0, /* static_pass_number */
1680 0, /* properties_required */
1681 0, /* properties_provided */
1682 0, /* properties_destroyed */
1683 0, /* todo_flags_start */
1684 TODO_dump_func
/* todo_flags_finish */
1689 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
1690 This means a type for which function calls must pass an address to the
1691 function or get an address back from the function.
1692 EXP may be a type node or an expression (whose type is tested). */
1695 aggregate_value_p (const_tree exp
, const_tree fntype
)
1697 int i
, regno
, nregs
;
1700 const_tree type
= (TYPE_P (exp
)) ? exp
: TREE_TYPE (exp
);
1702 /* DECL node associated with FNTYPE when relevant, which we might need to
1703 check for by-invisible-reference returns, typically for CALL_EXPR input
1705 const_tree fndecl
= NULL_TREE
;
1708 switch (TREE_CODE (fntype
))
1711 fndecl
= get_callee_fndecl (fntype
);
1712 fntype
= fndecl
? TREE_TYPE (fndecl
) : 0;
1716 fntype
= TREE_TYPE (fndecl
);
1721 case IDENTIFIER_NODE
:
1725 /* We don't expect other rtl types here. */
1729 if (TREE_CODE (type
) == VOID_TYPE
)
1732 /* If the front end has decided that this needs to be passed by
1733 reference, do so. */
1734 if ((TREE_CODE (exp
) == PARM_DECL
|| TREE_CODE (exp
) == RESULT_DECL
)
1735 && DECL_BY_REFERENCE (exp
))
1738 /* If the EXPression is a CALL_EXPR, honor DECL_BY_REFERENCE set on the
1739 called function RESULT_DECL, meaning the function returns in memory by
1740 invisible reference. This check lets front-ends not set TREE_ADDRESSABLE
1741 on the function type, which used to be the way to request such a return
1742 mechanism but might now be causing troubles at gimplification time if
1743 temporaries with the function type need to be created. */
1744 if (TREE_CODE (exp
) == CALL_EXPR
&& fndecl
&& DECL_RESULT (fndecl
)
1745 && DECL_BY_REFERENCE (DECL_RESULT (fndecl
)))
1748 if (targetm
.calls
.return_in_memory (type
, fntype
))
1750 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
1751 and thus can't be returned in registers. */
1752 if (TREE_ADDRESSABLE (type
))
1754 if (flag_pcc_struct_return
&& AGGREGATE_TYPE_P (type
))
1756 /* Make sure we have suitable call-clobbered regs to return
1757 the value in; if not, we must return it in memory. */
1758 reg
= hard_function_value (type
, 0, fntype
, 0);
1760 /* If we have something other than a REG (e.g. a PARALLEL), then assume
1765 regno
= REGNO (reg
);
1766 nregs
= hard_regno_nregs
[regno
][TYPE_MODE (type
)];
1767 for (i
= 0; i
< nregs
; i
++)
1768 if (! call_used_regs
[regno
+ i
])
1773 /* Return true if we should assign DECL a pseudo register; false if it
1774 should live on the local stack. */
1777 use_register_for_decl (const_tree decl
)
1779 /* Honor volatile. */
1780 if (TREE_SIDE_EFFECTS (decl
))
1783 /* Honor addressability. */
1784 if (TREE_ADDRESSABLE (decl
))
1787 /* Only register-like things go in registers. */
1788 if (DECL_MODE (decl
) == BLKmode
)
1791 /* If -ffloat-store specified, don't put explicit float variables
1793 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
1794 propagates values across these stores, and it probably shouldn't. */
1795 if (flag_float_store
&& FLOAT_TYPE_P (TREE_TYPE (decl
)))
1798 /* If we're not interested in tracking debugging information for
1799 this decl, then we can certainly put it in a register. */
1800 if (DECL_IGNORED_P (decl
))
1803 return (optimize
|| DECL_REGISTER (decl
));
1806 /* Return true if TYPE should be passed by invisible reference. */
1809 pass_by_reference (CUMULATIVE_ARGS
*ca
, enum machine_mode mode
,
1810 tree type
, bool named_arg
)
1814 /* If this type contains non-trivial constructors, then it is
1815 forbidden for the middle-end to create any new copies. */
1816 if (TREE_ADDRESSABLE (type
))
1819 /* GCC post 3.4 passes *all* variable sized types by reference. */
1820 if (!TYPE_SIZE (type
) || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
1824 return targetm
.calls
.pass_by_reference (ca
, mode
, type
, named_arg
);
1827 /* Return true if TYPE, which is passed by reference, should be callee
1828 copied instead of caller copied. */
1831 reference_callee_copied (CUMULATIVE_ARGS
*ca
, enum machine_mode mode
,
1832 tree type
, bool named_arg
)
1834 if (type
&& TREE_ADDRESSABLE (type
))
1836 return targetm
.calls
.callee_copies (ca
, mode
, type
, named_arg
);
1839 /* Structures to communicate between the subroutines of assign_parms.
1840 The first holds data persistent across all parameters, the second
1841 is cleared out for each parameter. */
1843 struct assign_parm_data_all
1845 CUMULATIVE_ARGS args_so_far
;
1846 struct args_size stack_args_size
;
1847 tree function_result_decl
;
1849 rtx first_conversion_insn
;
1850 rtx last_conversion_insn
;
1851 HOST_WIDE_INT pretend_args_size
;
1852 HOST_WIDE_INT extra_pretend_bytes
;
1853 int reg_parm_stack_space
;
1856 struct assign_parm_data_one
1862 enum machine_mode nominal_mode
;
1863 enum machine_mode passed_mode
;
1864 enum machine_mode promoted_mode
;
1865 struct locate_and_pad_arg_data locate
;
1867 BOOL_BITFIELD named_arg
: 1;
1868 BOOL_BITFIELD passed_pointer
: 1;
1869 BOOL_BITFIELD on_stack
: 1;
1870 BOOL_BITFIELD loaded_in_reg
: 1;
1873 /* A subroutine of assign_parms. Initialize ALL. */
1876 assign_parms_initialize_all (struct assign_parm_data_all
*all
)
1880 memset (all
, 0, sizeof (*all
));
1882 fntype
= TREE_TYPE (current_function_decl
);
1884 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
1885 INIT_CUMULATIVE_INCOMING_ARGS (all
->args_so_far
, fntype
, NULL_RTX
);
1887 INIT_CUMULATIVE_ARGS (all
->args_so_far
, fntype
, NULL_RTX
,
1888 current_function_decl
, -1);
1891 #ifdef REG_PARM_STACK_SPACE
1892 all
->reg_parm_stack_space
= REG_PARM_STACK_SPACE (current_function_decl
);
1896 /* If ARGS contains entries with complex types, split the entry into two
1897 entries of the component type. Return a new list of substitutions are
1898 needed, else the old list. */
1901 split_complex_args (tree args
)
1905 /* Before allocating memory, check for the common case of no complex. */
1906 for (p
= args
; p
; p
= TREE_CHAIN (p
))
1908 tree type
= TREE_TYPE (p
);
1909 if (TREE_CODE (type
) == COMPLEX_TYPE
1910 && targetm
.calls
.split_complex_arg (type
))
1916 args
= copy_list (args
);
1918 for (p
= args
; p
; p
= TREE_CHAIN (p
))
1920 tree type
= TREE_TYPE (p
);
1921 if (TREE_CODE (type
) == COMPLEX_TYPE
1922 && targetm
.calls
.split_complex_arg (type
))
1925 tree subtype
= TREE_TYPE (type
);
1926 bool addressable
= TREE_ADDRESSABLE (p
);
1928 /* Rewrite the PARM_DECL's type with its component. */
1929 TREE_TYPE (p
) = subtype
;
1930 DECL_ARG_TYPE (p
) = TREE_TYPE (DECL_ARG_TYPE (p
));
1931 DECL_MODE (p
) = VOIDmode
;
1932 DECL_SIZE (p
) = NULL
;
1933 DECL_SIZE_UNIT (p
) = NULL
;
1934 /* If this arg must go in memory, put it in a pseudo here.
1935 We can't allow it to go in memory as per normal parms,
1936 because the usual place might not have the imag part
1937 adjacent to the real part. */
1938 DECL_ARTIFICIAL (p
) = addressable
;
1939 DECL_IGNORED_P (p
) = addressable
;
1940 TREE_ADDRESSABLE (p
) = 0;
1943 /* Build a second synthetic decl. */
1944 decl
= build_decl (PARM_DECL
, NULL_TREE
, subtype
);
1945 DECL_ARG_TYPE (decl
) = DECL_ARG_TYPE (p
);
1946 DECL_ARTIFICIAL (decl
) = addressable
;
1947 DECL_IGNORED_P (decl
) = addressable
;
1948 layout_decl (decl
, 0);
1950 /* Splice it in; skip the new decl. */
1951 TREE_CHAIN (decl
) = TREE_CHAIN (p
);
1952 TREE_CHAIN (p
) = decl
;
1960 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
1961 the hidden struct return argument, and (abi willing) complex args.
1962 Return the new parameter list. */
1965 assign_parms_augmented_arg_list (struct assign_parm_data_all
*all
)
1967 tree fndecl
= current_function_decl
;
1968 tree fntype
= TREE_TYPE (fndecl
);
1969 tree fnargs
= DECL_ARGUMENTS (fndecl
);
1971 /* If struct value address is treated as the first argument, make it so. */
1972 if (aggregate_value_p (DECL_RESULT (fndecl
), fndecl
)
1973 && ! current_function_returns_pcc_struct
1974 && targetm
.calls
.struct_value_rtx (TREE_TYPE (fndecl
), 1) == 0)
1976 tree type
= build_pointer_type (TREE_TYPE (fntype
));
1979 decl
= build_decl (PARM_DECL
, NULL_TREE
, type
);
1980 DECL_ARG_TYPE (decl
) = type
;
1981 DECL_ARTIFICIAL (decl
) = 1;
1982 DECL_IGNORED_P (decl
) = 1;
1984 TREE_CHAIN (decl
) = fnargs
;
1986 all
->function_result_decl
= decl
;
1989 all
->orig_fnargs
= fnargs
;
1991 /* If the target wants to split complex arguments into scalars, do so. */
1992 if (targetm
.calls
.split_complex_arg
)
1993 fnargs
= split_complex_args (fnargs
);
1998 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
1999 data for the parameter. Incorporate ABI specifics such as pass-by-
2000 reference and type promotion. */
2003 assign_parm_find_data_types (struct assign_parm_data_all
*all
, tree parm
,
2004 struct assign_parm_data_one
*data
)
2006 tree nominal_type
, passed_type
;
2007 enum machine_mode nominal_mode
, passed_mode
, promoted_mode
;
2009 memset (data
, 0, sizeof (*data
));
2011 /* NAMED_ARG is a mis-nomer. We really mean 'non-varadic'. */
2012 if (!current_function_stdarg
)
2013 data
->named_arg
= 1; /* No varadic parms. */
2014 else if (TREE_CHAIN (parm
))
2015 data
->named_arg
= 1; /* Not the last non-varadic parm. */
2016 else if (targetm
.calls
.strict_argument_naming (&all
->args_so_far
))
2017 data
->named_arg
= 1; /* Only varadic ones are unnamed. */
2019 data
->named_arg
= 0; /* Treat as varadic. */
2021 nominal_type
= TREE_TYPE (parm
);
2022 passed_type
= DECL_ARG_TYPE (parm
);
2024 /* Look out for errors propagating this far. Also, if the parameter's
2025 type is void then its value doesn't matter. */
2026 if (TREE_TYPE (parm
) == error_mark_node
2027 /* This can happen after weird syntax errors
2028 or if an enum type is defined among the parms. */
2029 || TREE_CODE (parm
) != PARM_DECL
2030 || passed_type
== NULL
2031 || VOID_TYPE_P (nominal_type
))
2033 nominal_type
= passed_type
= void_type_node
;
2034 nominal_mode
= passed_mode
= promoted_mode
= VOIDmode
;
2038 /* Find mode of arg as it is passed, and mode of arg as it should be
2039 during execution of this function. */
2040 passed_mode
= TYPE_MODE (passed_type
);
2041 nominal_mode
= TYPE_MODE (nominal_type
);
2043 /* If the parm is to be passed as a transparent union, use the type of
2044 the first field for the tests below. We have already verified that
2045 the modes are the same. */
2046 if (TREE_CODE (passed_type
) == UNION_TYPE
2047 && TYPE_TRANSPARENT_UNION (passed_type
))
2048 passed_type
= TREE_TYPE (TYPE_FIELDS (passed_type
));
2050 /* See if this arg was passed by invisible reference. */
2051 if (pass_by_reference (&all
->args_so_far
, passed_mode
,
2052 passed_type
, data
->named_arg
))
2054 passed_type
= nominal_type
= build_pointer_type (passed_type
);
2055 data
->passed_pointer
= true;
2056 passed_mode
= nominal_mode
= Pmode
;
2059 /* Find mode as it is passed by the ABI. */
2060 promoted_mode
= passed_mode
;
2061 if (targetm
.calls
.promote_function_args (TREE_TYPE (current_function_decl
)))
2063 int unsignedp
= TYPE_UNSIGNED (passed_type
);
2064 promoted_mode
= promote_mode (passed_type
, promoted_mode
,
2069 data
->nominal_type
= nominal_type
;
2070 data
->passed_type
= passed_type
;
2071 data
->nominal_mode
= nominal_mode
;
2072 data
->passed_mode
= passed_mode
;
2073 data
->promoted_mode
= promoted_mode
;
2076 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2079 assign_parms_setup_varargs (struct assign_parm_data_all
*all
,
2080 struct assign_parm_data_one
*data
, bool no_rtl
)
2082 int varargs_pretend_bytes
= 0;
2084 targetm
.calls
.setup_incoming_varargs (&all
->args_so_far
,
2085 data
->promoted_mode
,
2087 &varargs_pretend_bytes
, no_rtl
);
2089 /* If the back-end has requested extra stack space, record how much is
2090 needed. Do not change pretend_args_size otherwise since it may be
2091 nonzero from an earlier partial argument. */
2092 if (varargs_pretend_bytes
> 0)
2093 all
->pretend_args_size
= varargs_pretend_bytes
;
2096 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2097 the incoming location of the current parameter. */
2100 assign_parm_find_entry_rtl (struct assign_parm_data_all
*all
,
2101 struct assign_parm_data_one
*data
)
2103 HOST_WIDE_INT pretend_bytes
= 0;
2107 if (data
->promoted_mode
== VOIDmode
)
2109 data
->entry_parm
= data
->stack_parm
= const0_rtx
;
2113 #ifdef FUNCTION_INCOMING_ARG
2114 entry_parm
= FUNCTION_INCOMING_ARG (all
->args_so_far
, data
->promoted_mode
,
2115 data
->passed_type
, data
->named_arg
);
2117 entry_parm
= FUNCTION_ARG (all
->args_so_far
, data
->promoted_mode
,
2118 data
->passed_type
, data
->named_arg
);
2121 if (entry_parm
== 0)
2122 data
->promoted_mode
= data
->passed_mode
;
2124 /* Determine parm's home in the stack, in case it arrives in the stack
2125 or we should pretend it did. Compute the stack position and rtx where
2126 the argument arrives and its size.
2128 There is one complexity here: If this was a parameter that would
2129 have been passed in registers, but wasn't only because it is
2130 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2131 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2132 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2133 as it was the previous time. */
2134 in_regs
= entry_parm
!= 0;
2135 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2138 if (!in_regs
&& !data
->named_arg
)
2140 if (targetm
.calls
.pretend_outgoing_varargs_named (&all
->args_so_far
))
2143 #ifdef FUNCTION_INCOMING_ARG
2144 tem
= FUNCTION_INCOMING_ARG (all
->args_so_far
, data
->promoted_mode
,
2145 data
->passed_type
, true);
2147 tem
= FUNCTION_ARG (all
->args_so_far
, data
->promoted_mode
,
2148 data
->passed_type
, true);
2150 in_regs
= tem
!= NULL
;
2154 /* If this parameter was passed both in registers and in the stack, use
2155 the copy on the stack. */
2156 if (targetm
.calls
.must_pass_in_stack (data
->promoted_mode
,
2164 partial
= targetm
.calls
.arg_partial_bytes (&all
->args_so_far
,
2165 data
->promoted_mode
,
2168 data
->partial
= partial
;
2170 /* The caller might already have allocated stack space for the
2171 register parameters. */
2172 if (partial
!= 0 && all
->reg_parm_stack_space
== 0)
2174 /* Part of this argument is passed in registers and part
2175 is passed on the stack. Ask the prologue code to extend
2176 the stack part so that we can recreate the full value.
2178 PRETEND_BYTES is the size of the registers we need to store.
2179 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2180 stack space that the prologue should allocate.
2182 Internally, gcc assumes that the argument pointer is aligned
2183 to STACK_BOUNDARY bits. This is used both for alignment
2184 optimizations (see init_emit) and to locate arguments that are
2185 aligned to more than PARM_BOUNDARY bits. We must preserve this
2186 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2187 a stack boundary. */
2189 /* We assume at most one partial arg, and it must be the first
2190 argument on the stack. */
2191 gcc_assert (!all
->extra_pretend_bytes
&& !all
->pretend_args_size
);
2193 pretend_bytes
= partial
;
2194 all
->pretend_args_size
= CEIL_ROUND (pretend_bytes
, STACK_BYTES
);
2196 /* We want to align relative to the actual stack pointer, so
2197 don't include this in the stack size until later. */
2198 all
->extra_pretend_bytes
= all
->pretend_args_size
;
2202 locate_and_pad_parm (data
->promoted_mode
, data
->passed_type
, in_regs
,
2203 entry_parm
? data
->partial
: 0, current_function_decl
,
2204 &all
->stack_args_size
, &data
->locate
);
2206 /* Adjust offsets to include the pretend args. */
2207 pretend_bytes
= all
->extra_pretend_bytes
- pretend_bytes
;
2208 data
->locate
.slot_offset
.constant
+= pretend_bytes
;
2209 data
->locate
.offset
.constant
+= pretend_bytes
;
2211 data
->entry_parm
= entry_parm
;
2214 /* A subroutine of assign_parms. If there is actually space on the stack
2215 for this parm, count it in stack_args_size and return true. */
2218 assign_parm_is_stack_parm (struct assign_parm_data_all
*all
,
2219 struct assign_parm_data_one
*data
)
2221 /* Trivially true if we've no incoming register. */
2222 if (data
->entry_parm
== NULL
)
2224 /* Also true if we're partially in registers and partially not,
2225 since we've arranged to drop the entire argument on the stack. */
2226 else if (data
->partial
!= 0)
2228 /* Also true if the target says that it's passed in both registers
2229 and on the stack. */
2230 else if (GET_CODE (data
->entry_parm
) == PARALLEL
2231 && XEXP (XVECEXP (data
->entry_parm
, 0, 0), 0) == NULL_RTX
)
2233 /* Also true if the target says that there's stack allocated for
2234 all register parameters. */
2235 else if (all
->reg_parm_stack_space
> 0)
2237 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2241 all
->stack_args_size
.constant
+= data
->locate
.size
.constant
;
2242 if (data
->locate
.size
.var
)
2243 ADD_PARM_SIZE (all
->stack_args_size
, data
->locate
.size
.var
);
2248 /* A subroutine of assign_parms. Given that this parameter is allocated
2249 stack space by the ABI, find it. */
2252 assign_parm_find_stack_rtl (tree parm
, struct assign_parm_data_one
*data
)
2254 rtx offset_rtx
, stack_parm
;
2255 unsigned int align
, boundary
;
2257 /* If we're passing this arg using a reg, make its stack home the
2258 aligned stack slot. */
2259 if (data
->entry_parm
)
2260 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.slot_offset
);
2262 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.offset
);
2264 stack_parm
= crtl
->args
.internal_arg_pointer
;
2265 if (offset_rtx
!= const0_rtx
)
2266 stack_parm
= gen_rtx_PLUS (Pmode
, stack_parm
, offset_rtx
);
2267 stack_parm
= gen_rtx_MEM (data
->promoted_mode
, stack_parm
);
2269 set_mem_attributes (stack_parm
, parm
, 1);
2271 boundary
= data
->locate
.boundary
;
2272 align
= BITS_PER_UNIT
;
2274 /* If we're padding upward, we know that the alignment of the slot
2275 is FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2276 intentionally forcing upward padding. Otherwise we have to come
2277 up with a guess at the alignment based on OFFSET_RTX. */
2278 if (data
->locate
.where_pad
!= downward
|| data
->entry_parm
)
2280 else if (GET_CODE (offset_rtx
) == CONST_INT
)
2282 align
= INTVAL (offset_rtx
) * BITS_PER_UNIT
| boundary
;
2283 align
= align
& -align
;
2285 set_mem_align (stack_parm
, align
);
2287 if (data
->entry_parm
)
2288 set_reg_attrs_for_parm (data
->entry_parm
, stack_parm
);
2290 data
->stack_parm
= stack_parm
;
2293 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2294 always valid and contiguous. */
2297 assign_parm_adjust_entry_rtl (struct assign_parm_data_one
*data
)
2299 rtx entry_parm
= data
->entry_parm
;
2300 rtx stack_parm
= data
->stack_parm
;
2302 /* If this parm was passed part in regs and part in memory, pretend it
2303 arrived entirely in memory by pushing the register-part onto the stack.
2304 In the special case of a DImode or DFmode that is split, we could put
2305 it together in a pseudoreg directly, but for now that's not worth
2307 if (data
->partial
!= 0)
2309 /* Handle calls that pass values in multiple non-contiguous
2310 locations. The Irix 6 ABI has examples of this. */
2311 if (GET_CODE (entry_parm
) == PARALLEL
)
2312 emit_group_store (validize_mem (stack_parm
), entry_parm
,
2314 int_size_in_bytes (data
->passed_type
));
2317 gcc_assert (data
->partial
% UNITS_PER_WORD
== 0);
2318 move_block_from_reg (REGNO (entry_parm
), validize_mem (stack_parm
),
2319 data
->partial
/ UNITS_PER_WORD
);
2322 entry_parm
= stack_parm
;
2325 /* If we didn't decide this parm came in a register, by default it came
2327 else if (entry_parm
== NULL
)
2328 entry_parm
= stack_parm
;
2330 /* When an argument is passed in multiple locations, we can't make use
2331 of this information, but we can save some copying if the whole argument
2332 is passed in a single register. */
2333 else if (GET_CODE (entry_parm
) == PARALLEL
2334 && data
->nominal_mode
!= BLKmode
2335 && data
->passed_mode
!= BLKmode
)
2337 size_t i
, len
= XVECLEN (entry_parm
, 0);
2339 for (i
= 0; i
< len
; i
++)
2340 if (XEXP (XVECEXP (entry_parm
, 0, i
), 0) != NULL_RTX
2341 && REG_P (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2342 && (GET_MODE (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2343 == data
->passed_mode
)
2344 && INTVAL (XEXP (XVECEXP (entry_parm
, 0, i
), 1)) == 0)
2346 entry_parm
= XEXP (XVECEXP (entry_parm
, 0, i
), 0);
2351 data
->entry_parm
= entry_parm
;
2354 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2355 always valid and properly aligned. */
2358 assign_parm_adjust_stack_rtl (struct assign_parm_data_one
*data
)
2360 rtx stack_parm
= data
->stack_parm
;
2362 /* If we can't trust the parm stack slot to be aligned enough for its
2363 ultimate type, don't use that slot after entry. We'll make another
2364 stack slot, if we need one. */
2366 && ((STRICT_ALIGNMENT
2367 && GET_MODE_ALIGNMENT (data
->nominal_mode
) > MEM_ALIGN (stack_parm
))
2368 || (data
->nominal_type
2369 && TYPE_ALIGN (data
->nominal_type
) > MEM_ALIGN (stack_parm
)
2370 && MEM_ALIGN (stack_parm
) < PREFERRED_STACK_BOUNDARY
)))
2373 /* If parm was passed in memory, and we need to convert it on entry,
2374 don't store it back in that same slot. */
2375 else if (data
->entry_parm
== stack_parm
2376 && data
->nominal_mode
!= BLKmode
2377 && data
->nominal_mode
!= data
->passed_mode
)
2380 /* If stack protection is in effect for this function, don't leave any
2381 pointers in their passed stack slots. */
2382 else if (cfun
->stack_protect_guard
2383 && (flag_stack_protect
== 2
2384 || data
->passed_pointer
2385 || POINTER_TYPE_P (data
->nominal_type
)))
2388 data
->stack_parm
= stack_parm
;
2391 /* A subroutine of assign_parms. Return true if the current parameter
2392 should be stored as a BLKmode in the current frame. */
2395 assign_parm_setup_block_p (struct assign_parm_data_one
*data
)
2397 if (data
->nominal_mode
== BLKmode
)
2399 if (GET_CODE (data
->entry_parm
) == PARALLEL
)
2402 #ifdef BLOCK_REG_PADDING
2403 /* Only assign_parm_setup_block knows how to deal with register arguments
2404 that are padded at the least significant end. */
2405 if (REG_P (data
->entry_parm
)
2406 && GET_MODE_SIZE (data
->promoted_mode
) < UNITS_PER_WORD
2407 && (BLOCK_REG_PADDING (data
->passed_mode
, data
->passed_type
, 1)
2408 == (BYTES_BIG_ENDIAN
? upward
: downward
)))
2415 /* A subroutine of assign_parms. Arrange for the parameter to be
2416 present and valid in DATA->STACK_RTL. */
2419 assign_parm_setup_block (struct assign_parm_data_all
*all
,
2420 tree parm
, struct assign_parm_data_one
*data
)
2422 rtx entry_parm
= data
->entry_parm
;
2423 rtx stack_parm
= data
->stack_parm
;
2425 HOST_WIDE_INT size_stored
;
2426 rtx orig_entry_parm
= entry_parm
;
2428 if (GET_CODE (entry_parm
) == PARALLEL
)
2429 entry_parm
= emit_group_move_into_temps (entry_parm
);
2431 /* If we've a non-block object that's nevertheless passed in parts,
2432 reconstitute it in register operations rather than on the stack. */
2433 if (GET_CODE (entry_parm
) == PARALLEL
2434 && data
->nominal_mode
!= BLKmode
)
2436 rtx elt0
= XEXP (XVECEXP (orig_entry_parm
, 0, 0), 0);
2438 if ((XVECLEN (entry_parm
, 0) > 1
2439 || hard_regno_nregs
[REGNO (elt0
)][GET_MODE (elt0
)] > 1)
2440 && use_register_for_decl (parm
))
2442 rtx parmreg
= gen_reg_rtx (data
->nominal_mode
);
2444 push_to_sequence2 (all
->first_conversion_insn
,
2445 all
->last_conversion_insn
);
2447 /* For values returned in multiple registers, handle possible
2448 incompatible calls to emit_group_store.
2450 For example, the following would be invalid, and would have to
2451 be fixed by the conditional below:
2453 emit_group_store ((reg:SF), (parallel:DF))
2454 emit_group_store ((reg:SI), (parallel:DI))
2456 An example of this are doubles in e500 v2:
2457 (parallel:DF (expr_list (reg:SI) (const_int 0))
2458 (expr_list (reg:SI) (const_int 4))). */
2459 if (data
->nominal_mode
!= data
->passed_mode
)
2461 rtx t
= gen_reg_rtx (GET_MODE (entry_parm
));
2462 emit_group_store (t
, entry_parm
, NULL_TREE
,
2463 GET_MODE_SIZE (GET_MODE (entry_parm
)));
2464 convert_move (parmreg
, t
, 0);
2467 emit_group_store (parmreg
, entry_parm
, data
->nominal_type
,
2468 int_size_in_bytes (data
->nominal_type
));
2470 all
->first_conversion_insn
= get_insns ();
2471 all
->last_conversion_insn
= get_last_insn ();
2474 SET_DECL_RTL (parm
, parmreg
);
2479 size
= int_size_in_bytes (data
->passed_type
);
2480 size_stored
= CEIL_ROUND (size
, UNITS_PER_WORD
);
2481 if (stack_parm
== 0)
2483 DECL_ALIGN (parm
) = MAX (DECL_ALIGN (parm
), BITS_PER_WORD
);
2484 stack_parm
= assign_stack_local (BLKmode
, size_stored
,
2486 if (GET_MODE_SIZE (GET_MODE (entry_parm
)) == size
)
2487 PUT_MODE (stack_parm
, GET_MODE (entry_parm
));
2488 set_mem_attributes (stack_parm
, parm
, 1);
2491 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2492 calls that pass values in multiple non-contiguous locations. */
2493 if (REG_P (entry_parm
) || GET_CODE (entry_parm
) == PARALLEL
)
2497 /* Note that we will be storing an integral number of words.
2498 So we have to be careful to ensure that we allocate an
2499 integral number of words. We do this above when we call
2500 assign_stack_local if space was not allocated in the argument
2501 list. If it was, this will not work if PARM_BOUNDARY is not
2502 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2503 if it becomes a problem. Exception is when BLKmode arrives
2504 with arguments not conforming to word_mode. */
2506 if (data
->stack_parm
== 0)
2508 else if (GET_CODE (entry_parm
) == PARALLEL
)
2511 gcc_assert (!size
|| !(PARM_BOUNDARY
% BITS_PER_WORD
));
2513 mem
= validize_mem (stack_parm
);
2515 /* Handle values in multiple non-contiguous locations. */
2516 if (GET_CODE (entry_parm
) == PARALLEL
)
2518 push_to_sequence2 (all
->first_conversion_insn
,
2519 all
->last_conversion_insn
);
2520 emit_group_store (mem
, entry_parm
, data
->passed_type
, size
);
2521 all
->first_conversion_insn
= get_insns ();
2522 all
->last_conversion_insn
= get_last_insn ();
2529 /* If SIZE is that of a mode no bigger than a word, just use
2530 that mode's store operation. */
2531 else if (size
<= UNITS_PER_WORD
)
2533 enum machine_mode mode
2534 = mode_for_size (size
* BITS_PER_UNIT
, MODE_INT
, 0);
2537 #ifdef BLOCK_REG_PADDING
2538 && (size
== UNITS_PER_WORD
2539 || (BLOCK_REG_PADDING (mode
, data
->passed_type
, 1)
2540 != (BYTES_BIG_ENDIAN
? upward
: downward
)))
2546 /* We are really truncating a word_mode value containing
2547 SIZE bytes into a value of mode MODE. If such an
2548 operation requires no actual instructions, we can refer
2549 to the value directly in mode MODE, otherwise we must
2550 start with the register in word_mode and explicitly
2552 if (TRULY_NOOP_TRUNCATION (size
* BITS_PER_UNIT
, BITS_PER_WORD
))
2553 reg
= gen_rtx_REG (mode
, REGNO (entry_parm
));
2556 reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
2557 reg
= convert_to_mode (mode
, copy_to_reg (reg
), 1);
2559 emit_move_insn (change_address (mem
, mode
, 0), reg
);
2562 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
2563 machine must be aligned to the left before storing
2564 to memory. Note that the previous test doesn't
2565 handle all cases (e.g. SIZE == 3). */
2566 else if (size
!= UNITS_PER_WORD
2567 #ifdef BLOCK_REG_PADDING
2568 && (BLOCK_REG_PADDING (mode
, data
->passed_type
, 1)
2576 int by
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
2577 rtx reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
2579 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
,
2580 build_int_cst (NULL_TREE
, by
),
2582 tem
= change_address (mem
, word_mode
, 0);
2583 emit_move_insn (tem
, x
);
2586 move_block_from_reg (REGNO (entry_parm
), mem
,
2587 size_stored
/ UNITS_PER_WORD
);
2590 move_block_from_reg (REGNO (entry_parm
), mem
,
2591 size_stored
/ UNITS_PER_WORD
);
2593 else if (data
->stack_parm
== 0)
2595 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2596 emit_block_move (stack_parm
, data
->entry_parm
, GEN_INT (size
),
2598 all
->first_conversion_insn
= get_insns ();
2599 all
->last_conversion_insn
= get_last_insn ();
2603 data
->stack_parm
= stack_parm
;
2604 SET_DECL_RTL (parm
, stack_parm
);
2607 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
2608 parameter. Get it there. Perform all ABI specified conversions. */
2611 assign_parm_setup_reg (struct assign_parm_data_all
*all
, tree parm
,
2612 struct assign_parm_data_one
*data
)
2615 enum machine_mode promoted_nominal_mode
;
2616 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (parm
));
2617 bool did_conversion
= false;
2619 /* Store the parm in a pseudoregister during the function, but we may
2620 need to do it in a wider mode. */
2622 /* This is not really promoting for a call. However we need to be
2623 consistent with assign_parm_find_data_types and expand_expr_real_1. */
2624 promoted_nominal_mode
2625 = promote_mode (data
->nominal_type
, data
->nominal_mode
, &unsignedp
, 1);
2627 parmreg
= gen_reg_rtx (promoted_nominal_mode
);
2629 if (!DECL_ARTIFICIAL (parm
))
2630 mark_user_reg (parmreg
);
2632 /* If this was an item that we received a pointer to,
2633 set DECL_RTL appropriately. */
2634 if (data
->passed_pointer
)
2636 rtx x
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data
->passed_type
)), parmreg
);
2637 set_mem_attributes (x
, parm
, 1);
2638 SET_DECL_RTL (parm
, x
);
2641 SET_DECL_RTL (parm
, parmreg
);
2643 /* Copy the value into the register. */
2644 if (data
->nominal_mode
!= data
->passed_mode
2645 || promoted_nominal_mode
!= data
->promoted_mode
)
2649 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
2650 mode, by the caller. We now have to convert it to
2651 NOMINAL_MODE, if different. However, PARMREG may be in
2652 a different mode than NOMINAL_MODE if it is being stored
2655 If ENTRY_PARM is a hard register, it might be in a register
2656 not valid for operating in its mode (e.g., an odd-numbered
2657 register for a DFmode). In that case, moves are the only
2658 thing valid, so we can't do a convert from there. This
2659 occurs when the calling sequence allow such misaligned
2662 In addition, the conversion may involve a call, which could
2663 clobber parameters which haven't been copied to pseudo
2664 registers yet. Therefore, we must first copy the parm to
2665 a pseudo reg here, and save the conversion until after all
2666 parameters have been moved. */
2668 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
2670 emit_move_insn (tempreg
, validize_mem (data
->entry_parm
));
2672 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2673 tempreg
= convert_to_mode (data
->nominal_mode
, tempreg
, unsignedp
);
2675 if (GET_CODE (tempreg
) == SUBREG
2676 && GET_MODE (tempreg
) == data
->nominal_mode
2677 && REG_P (SUBREG_REG (tempreg
))
2678 && data
->nominal_mode
== data
->passed_mode
2679 && GET_MODE (SUBREG_REG (tempreg
)) == GET_MODE (data
->entry_parm
)
2680 && GET_MODE_SIZE (GET_MODE (tempreg
))
2681 < GET_MODE_SIZE (GET_MODE (data
->entry_parm
)))
2683 /* The argument is already sign/zero extended, so note it
2685 SUBREG_PROMOTED_VAR_P (tempreg
) = 1;
2686 SUBREG_PROMOTED_UNSIGNED_SET (tempreg
, unsignedp
);
2689 /* TREE_USED gets set erroneously during expand_assignment. */
2690 save_tree_used
= TREE_USED (parm
);
2691 expand_assignment (parm
, make_tree (data
->nominal_type
, tempreg
), false);
2692 TREE_USED (parm
) = save_tree_used
;
2693 all
->first_conversion_insn
= get_insns ();
2694 all
->last_conversion_insn
= get_last_insn ();
2697 did_conversion
= true;
2700 emit_move_insn (parmreg
, validize_mem (data
->entry_parm
));
2702 /* If we were passed a pointer but the actual value can safely live
2703 in a register, put it in one. */
2704 if (data
->passed_pointer
2705 && TYPE_MODE (TREE_TYPE (parm
)) != BLKmode
2706 /* If by-reference argument was promoted, demote it. */
2707 && (TYPE_MODE (TREE_TYPE (parm
)) != GET_MODE (DECL_RTL (parm
))
2708 || use_register_for_decl (parm
)))
2710 /* We can't use nominal_mode, because it will have been set to
2711 Pmode above. We must use the actual mode of the parm. */
2712 parmreg
= gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm
)));
2713 mark_user_reg (parmreg
);
2715 if (GET_MODE (parmreg
) != GET_MODE (DECL_RTL (parm
)))
2717 rtx tempreg
= gen_reg_rtx (GET_MODE (DECL_RTL (parm
)));
2718 int unsigned_p
= TYPE_UNSIGNED (TREE_TYPE (parm
));
2720 push_to_sequence2 (all
->first_conversion_insn
,
2721 all
->last_conversion_insn
);
2722 emit_move_insn (tempreg
, DECL_RTL (parm
));
2723 tempreg
= convert_to_mode (GET_MODE (parmreg
), tempreg
, unsigned_p
);
2724 emit_move_insn (parmreg
, tempreg
);
2725 all
->first_conversion_insn
= get_insns ();
2726 all
->last_conversion_insn
= get_last_insn ();
2729 did_conversion
= true;
2732 emit_move_insn (parmreg
, DECL_RTL (parm
));
2734 SET_DECL_RTL (parm
, parmreg
);
2736 /* STACK_PARM is the pointer, not the parm, and PARMREG is
2738 data
->stack_parm
= NULL
;
2741 /* Mark the register as eliminable if we did no conversion and it was
2742 copied from memory at a fixed offset, and the arg pointer was not
2743 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
2744 offset formed an invalid address, such memory-equivalences as we
2745 make here would screw up life analysis for it. */
2746 if (data
->nominal_mode
== data
->passed_mode
2748 && data
->stack_parm
!= 0
2749 && MEM_P (data
->stack_parm
)
2750 && data
->locate
.offset
.var
== 0
2751 && reg_mentioned_p (virtual_incoming_args_rtx
,
2752 XEXP (data
->stack_parm
, 0)))
2754 rtx linsn
= get_last_insn ();
2757 /* Mark complex types separately. */
2758 if (GET_CODE (parmreg
) == CONCAT
)
2760 enum machine_mode submode
2761 = GET_MODE_INNER (GET_MODE (parmreg
));
2762 int regnor
= REGNO (XEXP (parmreg
, 0));
2763 int regnoi
= REGNO (XEXP (parmreg
, 1));
2764 rtx stackr
= adjust_address_nv (data
->stack_parm
, submode
, 0);
2765 rtx stacki
= adjust_address_nv (data
->stack_parm
, submode
,
2766 GET_MODE_SIZE (submode
));
2768 /* Scan backwards for the set of the real and
2770 for (sinsn
= linsn
; sinsn
!= 0;
2771 sinsn
= prev_nonnote_insn (sinsn
))
2773 set
= single_set (sinsn
);
2777 if (SET_DEST (set
) == regno_reg_rtx
[regnoi
])
2778 set_unique_reg_note (sinsn
, REG_EQUIV
, stacki
);
2779 else if (SET_DEST (set
) == regno_reg_rtx
[regnor
])
2780 set_unique_reg_note (sinsn
, REG_EQUIV
, stackr
);
2783 else if ((set
= single_set (linsn
)) != 0
2784 && SET_DEST (set
) == parmreg
)
2785 set_unique_reg_note (linsn
, REG_EQUIV
, data
->stack_parm
);
2788 /* For pointer data type, suggest pointer register. */
2789 if (POINTER_TYPE_P (TREE_TYPE (parm
)))
2790 mark_reg_pointer (parmreg
,
2791 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
2794 /* A subroutine of assign_parms. Allocate stack space to hold the current
2795 parameter. Get it there. Perform all ABI specified conversions. */
2798 assign_parm_setup_stack (struct assign_parm_data_all
*all
, tree parm
,
2799 struct assign_parm_data_one
*data
)
2801 /* Value must be stored in the stack slot STACK_PARM during function
2803 bool to_conversion
= false;
2805 if (data
->promoted_mode
!= data
->nominal_mode
)
2807 /* Conversion is required. */
2808 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
2810 emit_move_insn (tempreg
, validize_mem (data
->entry_parm
));
2812 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2813 to_conversion
= true;
2815 data
->entry_parm
= convert_to_mode (data
->nominal_mode
, tempreg
,
2816 TYPE_UNSIGNED (TREE_TYPE (parm
)));
2818 if (data
->stack_parm
)
2819 /* ??? This may need a big-endian conversion on sparc64. */
2821 = adjust_address (data
->stack_parm
, data
->nominal_mode
, 0);
2824 if (data
->entry_parm
!= data
->stack_parm
)
2828 if (data
->stack_parm
== 0)
2831 = assign_stack_local (GET_MODE (data
->entry_parm
),
2832 GET_MODE_SIZE (GET_MODE (data
->entry_parm
)),
2833 TYPE_ALIGN (data
->passed_type
));
2834 set_mem_attributes (data
->stack_parm
, parm
, 1);
2837 dest
= validize_mem (data
->stack_parm
);
2838 src
= validize_mem (data
->entry_parm
);
2842 /* Use a block move to handle potentially misaligned entry_parm. */
2844 push_to_sequence2 (all
->first_conversion_insn
,
2845 all
->last_conversion_insn
);
2846 to_conversion
= true;
2848 emit_block_move (dest
, src
,
2849 GEN_INT (int_size_in_bytes (data
->passed_type
)),
2853 emit_move_insn (dest
, src
);
2858 all
->first_conversion_insn
= get_insns ();
2859 all
->last_conversion_insn
= get_last_insn ();
2863 SET_DECL_RTL (parm
, data
->stack_parm
);
2866 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
2867 undo the frobbing that we did in assign_parms_augmented_arg_list. */
2870 assign_parms_unsplit_complex (struct assign_parm_data_all
*all
, tree fnargs
)
2873 tree orig_fnargs
= all
->orig_fnargs
;
2875 for (parm
= orig_fnargs
; parm
; parm
= TREE_CHAIN (parm
))
2877 if (TREE_CODE (TREE_TYPE (parm
)) == COMPLEX_TYPE
2878 && targetm
.calls
.split_complex_arg (TREE_TYPE (parm
)))
2880 rtx tmp
, real
, imag
;
2881 enum machine_mode inner
= GET_MODE_INNER (DECL_MODE (parm
));
2883 real
= DECL_RTL (fnargs
);
2884 imag
= DECL_RTL (TREE_CHAIN (fnargs
));
2885 if (inner
!= GET_MODE (real
))
2887 real
= gen_lowpart_SUBREG (inner
, real
);
2888 imag
= gen_lowpart_SUBREG (inner
, imag
);
2891 if (TREE_ADDRESSABLE (parm
))
2894 HOST_WIDE_INT size
= int_size_in_bytes (TREE_TYPE (parm
));
2896 /* split_complex_arg put the real and imag parts in
2897 pseudos. Move them to memory. */
2898 tmp
= assign_stack_local (DECL_MODE (parm
), size
,
2899 TYPE_ALIGN (TREE_TYPE (parm
)));
2900 set_mem_attributes (tmp
, parm
, 1);
2901 rmem
= adjust_address_nv (tmp
, inner
, 0);
2902 imem
= adjust_address_nv (tmp
, inner
, GET_MODE_SIZE (inner
));
2903 push_to_sequence2 (all
->first_conversion_insn
,
2904 all
->last_conversion_insn
);
2905 emit_move_insn (rmem
, real
);
2906 emit_move_insn (imem
, imag
);
2907 all
->first_conversion_insn
= get_insns ();
2908 all
->last_conversion_insn
= get_last_insn ();
2912 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
2913 SET_DECL_RTL (parm
, tmp
);
2915 real
= DECL_INCOMING_RTL (fnargs
);
2916 imag
= DECL_INCOMING_RTL (TREE_CHAIN (fnargs
));
2917 if (inner
!= GET_MODE (real
))
2919 real
= gen_lowpart_SUBREG (inner
, real
);
2920 imag
= gen_lowpart_SUBREG (inner
, imag
);
2922 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
2923 set_decl_incoming_rtl (parm
, tmp
, false);
2924 fnargs
= TREE_CHAIN (fnargs
);
2928 SET_DECL_RTL (parm
, DECL_RTL (fnargs
));
2929 set_decl_incoming_rtl (parm
, DECL_INCOMING_RTL (fnargs
), false);
2931 /* Set MEM_EXPR to the original decl, i.e. to PARM,
2932 instead of the copy of decl, i.e. FNARGS. */
2933 if (DECL_INCOMING_RTL (parm
) && MEM_P (DECL_INCOMING_RTL (parm
)))
2934 set_mem_expr (DECL_INCOMING_RTL (parm
), parm
);
2937 fnargs
= TREE_CHAIN (fnargs
);
2941 /* Assign RTL expressions to the function's parameters. This may involve
2942 copying them into registers and using those registers as the DECL_RTL. */
2945 assign_parms (tree fndecl
)
2947 struct assign_parm_data_all all
;
2950 crtl
->args
.internal_arg_pointer
2951 = targetm
.calls
.internal_arg_pointer ();
2953 assign_parms_initialize_all (&all
);
2954 fnargs
= assign_parms_augmented_arg_list (&all
);
2956 for (parm
= fnargs
; parm
; parm
= TREE_CHAIN (parm
))
2958 struct assign_parm_data_one data
;
2960 /* Extract the type of PARM; adjust it according to ABI. */
2961 assign_parm_find_data_types (&all
, parm
, &data
);
2963 /* Early out for errors and void parameters. */
2964 if (data
.passed_mode
== VOIDmode
)
2966 SET_DECL_RTL (parm
, const0_rtx
);
2967 DECL_INCOMING_RTL (parm
) = DECL_RTL (parm
);
2971 if (current_function_stdarg
&& !TREE_CHAIN (parm
))
2972 assign_parms_setup_varargs (&all
, &data
, false);
2974 /* Find out where the parameter arrives in this function. */
2975 assign_parm_find_entry_rtl (&all
, &data
);
2977 /* Find out where stack space for this parameter might be. */
2978 if (assign_parm_is_stack_parm (&all
, &data
))
2980 assign_parm_find_stack_rtl (parm
, &data
);
2981 assign_parm_adjust_entry_rtl (&data
);
2984 /* Record permanently how this parm was passed. */
2985 set_decl_incoming_rtl (parm
, data
.entry_parm
, data
.passed_pointer
);
2987 /* Update info on where next arg arrives in registers. */
2988 FUNCTION_ARG_ADVANCE (all
.args_so_far
, data
.promoted_mode
,
2989 data
.passed_type
, data
.named_arg
);
2991 assign_parm_adjust_stack_rtl (&data
);
2993 if (assign_parm_setup_block_p (&data
))
2994 assign_parm_setup_block (&all
, parm
, &data
);
2995 else if (data
.passed_pointer
|| use_register_for_decl (parm
))
2996 assign_parm_setup_reg (&all
, parm
, &data
);
2998 assign_parm_setup_stack (&all
, parm
, &data
);
3001 if (targetm
.calls
.split_complex_arg
&& fnargs
!= all
.orig_fnargs
)
3002 assign_parms_unsplit_complex (&all
, fnargs
);
3004 /* Output all parameter conversion instructions (possibly including calls)
3005 now that all parameters have been copied out of hard registers. */
3006 emit_insn (all
.first_conversion_insn
);
3008 /* If we are receiving a struct value address as the first argument, set up
3009 the RTL for the function result. As this might require code to convert
3010 the transmitted address to Pmode, we do this here to ensure that possible
3011 preliminary conversions of the address have been emitted already. */
3012 if (all
.function_result_decl
)
3014 tree result
= DECL_RESULT (current_function_decl
);
3015 rtx addr
= DECL_RTL (all
.function_result_decl
);
3018 if (DECL_BY_REFERENCE (result
))
3022 addr
= convert_memory_address (Pmode
, addr
);
3023 x
= gen_rtx_MEM (DECL_MODE (result
), addr
);
3024 set_mem_attributes (x
, result
, 1);
3026 SET_DECL_RTL (result
, x
);
3029 /* We have aligned all the args, so add space for the pretend args. */
3030 crtl
->args
.pretend_args_size
= all
.pretend_args_size
;
3031 all
.stack_args_size
.constant
+= all
.extra_pretend_bytes
;
3032 crtl
->args
.size
= all
.stack_args_size
.constant
;
3034 /* Adjust function incoming argument size for alignment and
3037 #ifdef REG_PARM_STACK_SPACE
3038 crtl
->args
.size
= MAX (crtl
->args
.size
,
3039 REG_PARM_STACK_SPACE (fndecl
));
3042 crtl
->args
.size
= CEIL_ROUND (crtl
->args
.size
,
3043 PARM_BOUNDARY
/ BITS_PER_UNIT
);
3045 #ifdef ARGS_GROW_DOWNWARD
3046 crtl
->args
.arg_offset_rtx
3047 = (all
.stack_args_size
.var
== 0 ? GEN_INT (-all
.stack_args_size
.constant
)
3048 : expand_expr (size_diffop (all
.stack_args_size
.var
,
3049 size_int (-all
.stack_args_size
.constant
)),
3050 NULL_RTX
, VOIDmode
, 0));
3052 crtl
->args
.arg_offset_rtx
= ARGS_SIZE_RTX (all
.stack_args_size
);
3055 /* See how many bytes, if any, of its args a function should try to pop
3058 crtl
->args
.pops_args
= RETURN_POPS_ARGS (fndecl
, TREE_TYPE (fndecl
),
3061 /* For stdarg.h function, save info about
3062 regs and stack space used by the named args. */
3064 crtl
->args
.info
= all
.args_so_far
;
3066 /* Set the rtx used for the function return value. Put this in its
3067 own variable so any optimizers that need this information don't have
3068 to include tree.h. Do this here so it gets done when an inlined
3069 function gets output. */
3072 = (DECL_RTL_SET_P (DECL_RESULT (fndecl
))
3073 ? DECL_RTL (DECL_RESULT (fndecl
)) : NULL_RTX
);
3075 /* If scalar return value was computed in a pseudo-reg, or was a named
3076 return value that got dumped to the stack, copy that to the hard
3078 if (DECL_RTL_SET_P (DECL_RESULT (fndecl
)))
3080 tree decl_result
= DECL_RESULT (fndecl
);
3081 rtx decl_rtl
= DECL_RTL (decl_result
);
3083 if (REG_P (decl_rtl
)
3084 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
3085 : DECL_REGISTER (decl_result
))
3089 real_decl_rtl
= targetm
.calls
.function_value (TREE_TYPE (decl_result
),
3091 REG_FUNCTION_VALUE_P (real_decl_rtl
) = 1;
3092 /* The delay slot scheduler assumes that crtl->return_rtx
3093 holds the hard register containing the return value, not a
3094 temporary pseudo. */
3095 crtl
->return_rtx
= real_decl_rtl
;
3100 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3101 For all seen types, gimplify their sizes. */
3104 gimplify_parm_type (tree
*tp
, int *walk_subtrees
, void *data
)
3111 if (POINTER_TYPE_P (t
))
3113 else if (TYPE_SIZE (t
) && !TREE_CONSTANT (TYPE_SIZE (t
))
3114 && !TYPE_SIZES_GIMPLIFIED (t
))
3116 gimplify_type_sizes (t
, (tree
*) data
);
3124 /* Gimplify the parameter list for current_function_decl. This involves
3125 evaluating SAVE_EXPRs of variable sized parameters and generating code
3126 to implement callee-copies reference parameters. Returns a list of
3127 statements to add to the beginning of the function, or NULL if nothing
3131 gimplify_parameters (void)
3133 struct assign_parm_data_all all
;
3134 tree fnargs
, parm
, stmts
= NULL
;
3136 assign_parms_initialize_all (&all
);
3137 fnargs
= assign_parms_augmented_arg_list (&all
);
3139 for (parm
= fnargs
; parm
; parm
= TREE_CHAIN (parm
))
3141 struct assign_parm_data_one data
;
3143 /* Extract the type of PARM; adjust it according to ABI. */
3144 assign_parm_find_data_types (&all
, parm
, &data
);
3146 /* Early out for errors and void parameters. */
3147 if (data
.passed_mode
== VOIDmode
|| DECL_SIZE (parm
) == NULL
)
3150 /* Update info on where next arg arrives in registers. */
3151 FUNCTION_ARG_ADVANCE (all
.args_so_far
, data
.promoted_mode
,
3152 data
.passed_type
, data
.named_arg
);
3154 /* ??? Once upon a time variable_size stuffed parameter list
3155 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3156 turned out to be less than manageable in the gimple world.
3157 Now we have to hunt them down ourselves. */
3158 walk_tree_without_duplicates (&data
.passed_type
,
3159 gimplify_parm_type
, &stmts
);
3161 if (!TREE_CONSTANT (DECL_SIZE (parm
)))
3163 gimplify_one_sizepos (&DECL_SIZE (parm
), &stmts
);
3164 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm
), &stmts
);
3167 if (data
.passed_pointer
)
3169 tree type
= TREE_TYPE (data
.passed_type
);
3170 if (reference_callee_copied (&all
.args_so_far
, TYPE_MODE (type
),
3171 type
, data
.named_arg
))
3175 /* For constant sized objects, this is trivial; for
3176 variable-sized objects, we have to play games. */
3177 if (TREE_CONSTANT (DECL_SIZE (parm
)))
3179 local
= create_tmp_var (type
, get_name (parm
));
3180 DECL_IGNORED_P (local
) = 0;
3184 tree ptr_type
, addr
;
3186 ptr_type
= build_pointer_type (type
);
3187 addr
= create_tmp_var (ptr_type
, get_name (parm
));
3188 DECL_IGNORED_P (addr
) = 0;
3189 local
= build_fold_indirect_ref (addr
);
3191 t
= built_in_decls
[BUILT_IN_ALLOCA
];
3192 t
= build_call_expr (t
, 1, DECL_SIZE_UNIT (parm
));
3193 t
= fold_convert (ptr_type
, t
);
3194 t
= build_gimple_modify_stmt (addr
, t
);
3195 gimplify_and_add (t
, &stmts
);
3198 t
= build_gimple_modify_stmt (local
, parm
);
3199 gimplify_and_add (t
, &stmts
);
3201 SET_DECL_VALUE_EXPR (parm
, local
);
3202 DECL_HAS_VALUE_EXPR_P (parm
) = 1;
3210 /* Compute the size and offset from the start of the stacked arguments for a
3211 parm passed in mode PASSED_MODE and with type TYPE.
3213 INITIAL_OFFSET_PTR points to the current offset into the stacked
3216 The starting offset and size for this parm are returned in
3217 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3218 nonzero, the offset is that of stack slot, which is returned in
3219 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3220 padding required from the initial offset ptr to the stack slot.
3222 IN_REGS is nonzero if the argument will be passed in registers. It will
3223 never be set if REG_PARM_STACK_SPACE is not defined.
3225 FNDECL is the function in which the argument was defined.
3227 There are two types of rounding that are done. The first, controlled by
3228 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
3229 list to be aligned to the specific boundary (in bits). This rounding
3230 affects the initial and starting offsets, but not the argument size.
3232 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3233 optionally rounds the size of the parm to PARM_BOUNDARY. The
3234 initial offset is not affected by this rounding, while the size always
3235 is and the starting offset may be. */
3237 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3238 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3239 callers pass in the total size of args so far as
3240 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
3243 locate_and_pad_parm (enum machine_mode passed_mode
, tree type
, int in_regs
,
3244 int partial
, tree fndecl ATTRIBUTE_UNUSED
,
3245 struct args_size
*initial_offset_ptr
,
3246 struct locate_and_pad_arg_data
*locate
)
3249 enum direction where_pad
;
3250 unsigned int boundary
;
3251 int reg_parm_stack_space
= 0;
3252 int part_size_in_regs
;
3254 #ifdef REG_PARM_STACK_SPACE
3255 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
3257 /* If we have found a stack parm before we reach the end of the
3258 area reserved for registers, skip that area. */
3261 if (reg_parm_stack_space
> 0)
3263 if (initial_offset_ptr
->var
)
3265 initial_offset_ptr
->var
3266 = size_binop (MAX_EXPR
, ARGS_SIZE_TREE (*initial_offset_ptr
),
3267 ssize_int (reg_parm_stack_space
));
3268 initial_offset_ptr
->constant
= 0;
3270 else if (initial_offset_ptr
->constant
< reg_parm_stack_space
)
3271 initial_offset_ptr
->constant
= reg_parm_stack_space
;
3274 #endif /* REG_PARM_STACK_SPACE */
3276 part_size_in_regs
= (reg_parm_stack_space
== 0 ? partial
: 0);
3279 = type
? size_in_bytes (type
) : size_int (GET_MODE_SIZE (passed_mode
));
3280 where_pad
= FUNCTION_ARG_PADDING (passed_mode
, type
);
3281 boundary
= FUNCTION_ARG_BOUNDARY (passed_mode
, type
);
3282 locate
->where_pad
= where_pad
;
3283 locate
->boundary
= boundary
;
3285 /* Remember if the outgoing parameter requires extra alignment on the
3286 calling function side. */
3287 if (boundary
> PREFERRED_STACK_BOUNDARY
)
3288 boundary
= PREFERRED_STACK_BOUNDARY
;
3289 if (cfun
->stack_alignment_needed
< boundary
)
3290 cfun
->stack_alignment_needed
= boundary
;
3292 #ifdef ARGS_GROW_DOWNWARD
3293 locate
->slot_offset
.constant
= -initial_offset_ptr
->constant
;
3294 if (initial_offset_ptr
->var
)
3295 locate
->slot_offset
.var
= size_binop (MINUS_EXPR
, ssize_int (0),
3296 initial_offset_ptr
->var
);
3300 if (where_pad
!= none
3301 && (!host_integerp (sizetree
, 1)
3302 || (tree_low_cst (sizetree
, 1) * BITS_PER_UNIT
) % PARM_BOUNDARY
))
3303 s2
= round_up (s2
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3304 SUB_PARM_SIZE (locate
->slot_offset
, s2
);
3307 locate
->slot_offset
.constant
+= part_size_in_regs
;
3310 #ifdef REG_PARM_STACK_SPACE
3311 || REG_PARM_STACK_SPACE (fndecl
) > 0
3314 pad_to_arg_alignment (&locate
->slot_offset
, boundary
,
3315 &locate
->alignment_pad
);
3317 locate
->size
.constant
= (-initial_offset_ptr
->constant
3318 - locate
->slot_offset
.constant
);
3319 if (initial_offset_ptr
->var
)
3320 locate
->size
.var
= size_binop (MINUS_EXPR
,
3321 size_binop (MINUS_EXPR
,
3323 initial_offset_ptr
->var
),
3324 locate
->slot_offset
.var
);
3326 /* Pad_below needs the pre-rounded size to know how much to pad
3328 locate
->offset
= locate
->slot_offset
;
3329 if (where_pad
== downward
)
3330 pad_below (&locate
->offset
, passed_mode
, sizetree
);
3332 #else /* !ARGS_GROW_DOWNWARD */
3334 #ifdef REG_PARM_STACK_SPACE
3335 || REG_PARM_STACK_SPACE (fndecl
) > 0
3338 pad_to_arg_alignment (initial_offset_ptr
, boundary
,
3339 &locate
->alignment_pad
);
3340 locate
->slot_offset
= *initial_offset_ptr
;
3342 #ifdef PUSH_ROUNDING
3343 if (passed_mode
!= BLKmode
)
3344 sizetree
= size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree
)));
3347 /* Pad_below needs the pre-rounded size to know how much to pad below
3348 so this must be done before rounding up. */
3349 locate
->offset
= locate
->slot_offset
;
3350 if (where_pad
== downward
)
3351 pad_below (&locate
->offset
, passed_mode
, sizetree
);
3353 if (where_pad
!= none
3354 && (!host_integerp (sizetree
, 1)
3355 || (tree_low_cst (sizetree
, 1) * BITS_PER_UNIT
) % PARM_BOUNDARY
))
3356 sizetree
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3358 ADD_PARM_SIZE (locate
->size
, sizetree
);
3360 locate
->size
.constant
-= part_size_in_regs
;
3361 #endif /* ARGS_GROW_DOWNWARD */
3364 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
3365 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
3368 pad_to_arg_alignment (struct args_size
*offset_ptr
, int boundary
,
3369 struct args_size
*alignment_pad
)
3371 tree save_var
= NULL_TREE
;
3372 HOST_WIDE_INT save_constant
= 0;
3373 int boundary_in_bytes
= boundary
/ BITS_PER_UNIT
;
3374 HOST_WIDE_INT sp_offset
= STACK_POINTER_OFFSET
;
3376 #ifdef SPARC_STACK_BOUNDARY_HACK
3377 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
3378 the real alignment of %sp. However, when it does this, the
3379 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
3380 if (SPARC_STACK_BOUNDARY_HACK
)
3384 if (boundary
> PARM_BOUNDARY
)
3386 save_var
= offset_ptr
->var
;
3387 save_constant
= offset_ptr
->constant
;
3390 alignment_pad
->var
= NULL_TREE
;
3391 alignment_pad
->constant
= 0;
3393 if (boundary
> BITS_PER_UNIT
)
3395 if (offset_ptr
->var
)
3397 tree sp_offset_tree
= ssize_int (sp_offset
);
3398 tree offset
= size_binop (PLUS_EXPR
,
3399 ARGS_SIZE_TREE (*offset_ptr
),
3401 #ifdef ARGS_GROW_DOWNWARD
3402 tree rounded
= round_down (offset
, boundary
/ BITS_PER_UNIT
);
3404 tree rounded
= round_up (offset
, boundary
/ BITS_PER_UNIT
);
3407 offset_ptr
->var
= size_binop (MINUS_EXPR
, rounded
, sp_offset_tree
);
3408 /* ARGS_SIZE_TREE includes constant term. */
3409 offset_ptr
->constant
= 0;
3410 if (boundary
> PARM_BOUNDARY
)
3411 alignment_pad
->var
= size_binop (MINUS_EXPR
, offset_ptr
->var
,
3416 offset_ptr
->constant
= -sp_offset
+
3417 #ifdef ARGS_GROW_DOWNWARD
3418 FLOOR_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
3420 CEIL_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
3422 if (boundary
> PARM_BOUNDARY
)
3423 alignment_pad
->constant
= offset_ptr
->constant
- save_constant
;
3429 pad_below (struct args_size
*offset_ptr
, enum machine_mode passed_mode
, tree sizetree
)
3431 if (passed_mode
!= BLKmode
)
3433 if (GET_MODE_BITSIZE (passed_mode
) % PARM_BOUNDARY
)
3434 offset_ptr
->constant
3435 += (((GET_MODE_BITSIZE (passed_mode
) + PARM_BOUNDARY
- 1)
3436 / PARM_BOUNDARY
* PARM_BOUNDARY
/ BITS_PER_UNIT
)
3437 - GET_MODE_SIZE (passed_mode
));
3441 if (TREE_CODE (sizetree
) != INTEGER_CST
3442 || (TREE_INT_CST_LOW (sizetree
) * BITS_PER_UNIT
) % PARM_BOUNDARY
)
3444 /* Round the size up to multiple of PARM_BOUNDARY bits. */
3445 tree s2
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3447 ADD_PARM_SIZE (*offset_ptr
, s2
);
3448 SUB_PARM_SIZE (*offset_ptr
, sizetree
);
3454 /* True if register REGNO was alive at a place where `setjmp' was
3455 called and was set more than once or is an argument. Such regs may
3456 be clobbered by `longjmp'. */
3459 regno_clobbered_at_setjmp (bitmap setjmp_crosses
, int regno
)
3461 /* There appear to be cases where some local vars never reach the
3462 backend but have bogus regnos. */
3463 if (regno
>= max_reg_num ())
3466 return ((REG_N_SETS (regno
) > 1
3467 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR
), regno
))
3468 && REGNO_REG_SET_P (setjmp_crosses
, regno
));
3471 /* Walk the tree of blocks describing the binding levels within a
3472 function and warn about variables the might be killed by setjmp or
3473 vfork. This is done after calling flow_analysis before register
3474 allocation since that will clobber the pseudo-regs to hard
3478 setjmp_vars_warning (bitmap setjmp_crosses
, tree block
)
3482 for (decl
= BLOCK_VARS (block
); decl
; decl
= TREE_CHAIN (decl
))
3484 if (TREE_CODE (decl
) == VAR_DECL
3485 && DECL_RTL_SET_P (decl
)
3486 && REG_P (DECL_RTL (decl
))
3487 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
3488 warning (OPT_Wclobbered
, "variable %q+D might be clobbered by"
3489 " %<longjmp%> or %<vfork%>", decl
);
3492 for (sub
= BLOCK_SUBBLOCKS (block
); sub
; sub
= BLOCK_CHAIN (sub
))
3493 setjmp_vars_warning (setjmp_crosses
, sub
);
3496 /* Do the appropriate part of setjmp_vars_warning
3497 but for arguments instead of local variables. */
3500 setjmp_args_warning (bitmap setjmp_crosses
)
3503 for (decl
= DECL_ARGUMENTS (current_function_decl
);
3504 decl
; decl
= TREE_CHAIN (decl
))
3505 if (DECL_RTL (decl
) != 0
3506 && REG_P (DECL_RTL (decl
))
3507 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
3508 warning (OPT_Wclobbered
,
3509 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
3513 /* Generate warning messages for variables live across setjmp. */
3516 generate_setjmp_warnings (void)
3518 bitmap setjmp_crosses
= regstat_get_setjmp_crosses ();
3520 if (n_basic_blocks
== NUM_FIXED_BLOCKS
3521 || bitmap_empty_p (setjmp_crosses
))
3524 setjmp_vars_warning (setjmp_crosses
, DECL_INITIAL (current_function_decl
));
3525 setjmp_args_warning (setjmp_crosses
);
3529 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
3530 and create duplicate blocks. */
3531 /* ??? Need an option to either create block fragments or to create
3532 abstract origin duplicates of a source block. It really depends
3533 on what optimization has been performed. */
3536 reorder_blocks (void)
3538 tree block
= DECL_INITIAL (current_function_decl
);
3539 VEC(tree
,heap
) *block_stack
;
3541 if (block
== NULL_TREE
)
3544 block_stack
= VEC_alloc (tree
, heap
, 10);
3546 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
3547 clear_block_marks (block
);
3549 /* Prune the old trees away, so that they don't get in the way. */
3550 BLOCK_SUBBLOCKS (block
) = NULL_TREE
;
3551 BLOCK_CHAIN (block
) = NULL_TREE
;
3553 /* Recreate the block tree from the note nesting. */
3554 reorder_blocks_1 (get_insns (), block
, &block_stack
);
3555 BLOCK_SUBBLOCKS (block
) = blocks_nreverse (BLOCK_SUBBLOCKS (block
));
3557 VEC_free (tree
, heap
, block_stack
);
3560 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
3563 clear_block_marks (tree block
)
3567 TREE_ASM_WRITTEN (block
) = 0;
3568 clear_block_marks (BLOCK_SUBBLOCKS (block
));
3569 block
= BLOCK_CHAIN (block
);
3574 reorder_blocks_1 (rtx insns
, tree current_block
, VEC(tree
,heap
) **p_block_stack
)
3578 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
3582 if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_BEG
)
3584 tree block
= NOTE_BLOCK (insn
);
3587 origin
= (BLOCK_FRAGMENT_ORIGIN (block
)
3588 ? BLOCK_FRAGMENT_ORIGIN (block
)
3591 /* If we have seen this block before, that means it now
3592 spans multiple address regions. Create a new fragment. */
3593 if (TREE_ASM_WRITTEN (block
))
3595 tree new_block
= copy_node (block
);
3597 BLOCK_FRAGMENT_ORIGIN (new_block
) = origin
;
3598 BLOCK_FRAGMENT_CHAIN (new_block
)
3599 = BLOCK_FRAGMENT_CHAIN (origin
);
3600 BLOCK_FRAGMENT_CHAIN (origin
) = new_block
;
3602 NOTE_BLOCK (insn
) = new_block
;
3606 BLOCK_SUBBLOCKS (block
) = 0;
3607 TREE_ASM_WRITTEN (block
) = 1;
3608 /* When there's only one block for the entire function,
3609 current_block == block and we mustn't do this, it
3610 will cause infinite recursion. */
3611 if (block
!= current_block
)
3613 if (block
!= origin
)
3614 gcc_assert (BLOCK_SUPERCONTEXT (origin
) == current_block
);
3616 BLOCK_SUPERCONTEXT (block
) = current_block
;
3617 BLOCK_CHAIN (block
) = BLOCK_SUBBLOCKS (current_block
);
3618 BLOCK_SUBBLOCKS (current_block
) = block
;
3619 current_block
= origin
;
3621 VEC_safe_push (tree
, heap
, *p_block_stack
, block
);
3623 else if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_END
)
3625 NOTE_BLOCK (insn
) = VEC_pop (tree
, *p_block_stack
);
3626 BLOCK_SUBBLOCKS (current_block
)
3627 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block
));
3628 current_block
= BLOCK_SUPERCONTEXT (current_block
);
3634 /* Reverse the order of elements in the chain T of blocks,
3635 and return the new head of the chain (old last element). */
3638 blocks_nreverse (tree t
)
3640 tree prev
= 0, decl
, next
;
3641 for (decl
= t
; decl
; decl
= next
)
3643 next
= BLOCK_CHAIN (decl
);
3644 BLOCK_CHAIN (decl
) = prev
;
3650 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
3651 non-NULL, list them all into VECTOR, in a depth-first preorder
3652 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
3656 all_blocks (tree block
, tree
*vector
)
3662 TREE_ASM_WRITTEN (block
) = 0;
3664 /* Record this block. */
3666 vector
[n_blocks
] = block
;
3670 /* Record the subblocks, and their subblocks... */
3671 n_blocks
+= all_blocks (BLOCK_SUBBLOCKS (block
),
3672 vector
? vector
+ n_blocks
: 0);
3673 block
= BLOCK_CHAIN (block
);
3679 /* Return a vector containing all the blocks rooted at BLOCK. The
3680 number of elements in the vector is stored in N_BLOCKS_P. The
3681 vector is dynamically allocated; it is the caller's responsibility
3682 to call `free' on the pointer returned. */
3685 get_block_vector (tree block
, int *n_blocks_p
)
3689 *n_blocks_p
= all_blocks (block
, NULL
);
3690 block_vector
= XNEWVEC (tree
, *n_blocks_p
);
3691 all_blocks (block
, block_vector
);
3693 return block_vector
;
3696 static GTY(()) int next_block_index
= 2;
3698 /* Set BLOCK_NUMBER for all the blocks in FN. */
3701 number_blocks (tree fn
)
3707 /* For SDB and XCOFF debugging output, we start numbering the blocks
3708 from 1 within each function, rather than keeping a running
3710 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
3711 if (write_symbols
== SDB_DEBUG
|| write_symbols
== XCOFF_DEBUG
)
3712 next_block_index
= 1;
3715 block_vector
= get_block_vector (DECL_INITIAL (fn
), &n_blocks
);
3717 /* The top-level BLOCK isn't numbered at all. */
3718 for (i
= 1; i
< n_blocks
; ++i
)
3719 /* We number the blocks from two. */
3720 BLOCK_NUMBER (block_vector
[i
]) = next_block_index
++;
3722 free (block_vector
);
3727 /* If VAR is present in a subblock of BLOCK, return the subblock. */
3730 debug_find_var_in_block_tree (tree var
, tree block
)
3734 for (t
= BLOCK_VARS (block
); t
; t
= TREE_CHAIN (t
))
3738 for (t
= BLOCK_SUBBLOCKS (block
); t
; t
= TREE_CHAIN (t
))
3740 tree ret
= debug_find_var_in_block_tree (var
, t
);
3748 /* Keep track of whether we're in a dummy function context. If we are,
3749 we don't want to invoke the set_current_function hook, because we'll
3750 get into trouble if the hook calls target_reinit () recursively or
3751 when the initial initialization is not yet complete. */
3753 static bool in_dummy_function
;
3755 /* Invoke the target hook when setting cfun. */
3758 invoke_set_current_function_hook (tree fndecl
)
3760 if (!in_dummy_function
)
3761 targetm
.set_current_function (fndecl
);
3764 /* cfun should never be set directly; use this function. */
3767 set_cfun (struct function
*new_cfun
)
3769 if (cfun
!= new_cfun
)
3772 invoke_set_current_function_hook (new_cfun
? new_cfun
->decl
: NULL_TREE
);
3776 /* Keep track of the cfun stack. */
3778 typedef struct function
*function_p
;
3780 DEF_VEC_P(function_p
);
3781 DEF_VEC_ALLOC_P(function_p
,heap
);
3783 /* Initialized with NOGC, making this poisonous to the garbage collector. */
3785 static VEC(function_p
,heap
) *cfun_stack
;
3787 /* We save the value of in_system_header here when pushing the first
3788 function on the cfun stack, and we restore it from here when
3789 popping the last function. */
3791 static bool saved_in_system_header
;
3793 /* Push the current cfun onto the stack, and set cfun to new_cfun. */
3796 push_cfun (struct function
*new_cfun
)
3799 saved_in_system_header
= in_system_header
;
3800 VEC_safe_push (function_p
, heap
, cfun_stack
, cfun
);
3802 in_system_header
= DECL_IN_SYSTEM_HEADER (new_cfun
->decl
);
3803 set_cfun (new_cfun
);
3806 /* Pop cfun from the stack. */
3811 struct function
*new_cfun
= VEC_pop (function_p
, cfun_stack
);
3812 in_system_header
= ((new_cfun
== NULL
) ? saved_in_system_header
3813 : DECL_IN_SYSTEM_HEADER (new_cfun
->decl
));
3814 set_cfun (new_cfun
);
3817 /* Return value of funcdef and increase it. */
3819 get_next_funcdef_no (void)
3821 return funcdef_no
++;
3824 /* Allocate a function structure for FNDECL and set its contents
3825 to the defaults. Set cfun to the newly-allocated object.
3826 Some of the helper functions invoked during initialization assume
3827 that cfun has already been set. Therefore, assign the new object
3828 directly into cfun and invoke the back end hook explicitly at the
3829 very end, rather than initializing a temporary and calling set_cfun
3832 ABSTRACT_P is true if this is a function that will never be seen by
3833 the middle-end. Such functions are front-end concepts (like C++
3834 function templates) that do not correspond directly to functions
3835 placed in object files. */
3838 allocate_struct_function (tree fndecl
, bool abstract_p
)
3841 tree fntype
= fndecl
? TREE_TYPE (fndecl
) : NULL_TREE
;
3843 cfun
= ggc_alloc_cleared (sizeof (struct function
));
3845 cfun
->stack_alignment_needed
= STACK_BOUNDARY
;
3846 cfun
->preferred_stack_boundary
= STACK_BOUNDARY
;
3848 current_function_funcdef_no
= get_next_funcdef_no ();
3850 cfun
->function_frequency
= FUNCTION_FREQUENCY_NORMAL
;
3852 init_eh_for_function ();
3854 if (init_machine_status
)
3855 cfun
->machine
= (*init_machine_status
) ();
3859 DECL_STRUCT_FUNCTION (fndecl
) = cfun
;
3860 cfun
->decl
= fndecl
;
3862 result
= DECL_RESULT (fndecl
);
3863 if (!abstract_p
&& aggregate_value_p (result
, fndecl
))
3865 #ifdef PCC_STATIC_STRUCT_RETURN
3866 current_function_returns_pcc_struct
= 1;
3868 current_function_returns_struct
= 1;
3871 current_function_stdarg
3873 && TYPE_ARG_TYPES (fntype
) != 0
3874 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype
)))
3875 != void_type_node
));
3877 /* Assume all registers in stdarg functions need to be saved. */
3878 cfun
->va_list_gpr_size
= VA_LIST_MAX_GPR_SIZE
;
3879 cfun
->va_list_fpr_size
= VA_LIST_MAX_FPR_SIZE
;
3882 invoke_set_current_function_hook (fndecl
);
3885 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
3886 instead of just setting it. */
3889 push_struct_function (tree fndecl
)
3892 saved_in_system_header
= in_system_header
;
3893 VEC_safe_push (function_p
, heap
, cfun_stack
, cfun
);
3895 in_system_header
= DECL_IN_SYSTEM_HEADER (fndecl
);
3896 allocate_struct_function (fndecl
, false);
3899 /* Reset cfun, and other non-struct-function variables to defaults as
3900 appropriate for emitting rtl at the start of a function. */
3903 prepare_function_start (void)
3905 gcc_assert (!crtl
->emit
.x_last_insn
);
3907 init_varasm_status ();
3910 cse_not_expected
= ! optimize
;
3912 /* Caller save not needed yet. */
3913 caller_save_needed
= 0;
3915 /* We haven't done register allocation yet. */
3918 /* Indicate that we have not instantiated virtual registers yet. */
3919 virtuals_instantiated
= 0;
3921 /* Indicate that we want CONCATs now. */
3922 generating_concat_p
= 1;
3924 /* Indicate we have no need of a frame pointer yet. */
3925 frame_pointer_needed
= 0;
3928 /* Initialize the rtl expansion mechanism so that we can do simple things
3929 like generate sequences. This is used to provide a context during global
3930 initialization of some passes. You must call expand_dummy_function_end
3931 to exit this context. */
3934 init_dummy_function_start (void)
3936 gcc_assert (!in_dummy_function
);
3937 in_dummy_function
= true;
3938 push_struct_function (NULL_TREE
);
3939 prepare_function_start ();
3942 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
3943 and initialize static variables for generating RTL for the statements
3947 init_function_start (tree subr
)
3949 if (subr
&& DECL_STRUCT_FUNCTION (subr
))
3950 set_cfun (DECL_STRUCT_FUNCTION (subr
));
3952 allocate_struct_function (subr
, false);
3953 prepare_function_start ();
3955 /* Warn if this value is an aggregate type,
3956 regardless of which calling convention we are using for it. */
3957 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr
))))
3958 warning (OPT_Waggregate_return
, "function returns an aggregate");
3961 /* Make sure all values used by the optimization passes have sane
3964 init_function_for_compilation (void)
3968 /* No prologue/epilogue insns yet. Make sure that these vectors are
3970 gcc_assert (VEC_length (int, prologue
) == 0);
3971 gcc_assert (VEC_length (int, epilogue
) == 0);
3972 gcc_assert (VEC_length (int, sibcall_epilogue
) == 0);
3976 struct rtl_opt_pass pass_init_function
=
3982 init_function_for_compilation
, /* execute */
3985 0, /* static_pass_number */
3987 0, /* properties_required */
3988 0, /* properties_provided */
3989 0, /* properties_destroyed */
3990 0, /* todo_flags_start */
3991 0 /* todo_flags_finish */
3997 expand_main_function (void)
3999 #if (defined(INVOKE__main) \
4000 || (!defined(HAS_INIT_SECTION) \
4001 && !defined(INIT_SECTION_ASM_OP) \
4002 && !defined(INIT_ARRAY_SECTION_ASM_OP)))
4003 emit_library_call (init_one_libfunc (NAME__MAIN
), LCT_NORMAL
, VOIDmode
, 0);
4007 /* Expand code to initialize the stack_protect_guard. This is invoked at
4008 the beginning of a function to be protected. */
4010 #ifndef HAVE_stack_protect_set
4011 # define HAVE_stack_protect_set 0
4012 # define gen_stack_protect_set(x,y) (gcc_unreachable (), NULL_RTX)
4016 stack_protect_prologue (void)
4018 tree guard_decl
= targetm
.stack_protect_guard ();
4021 /* Avoid expand_expr here, because we don't want guard_decl pulled
4022 into registers unless absolutely necessary. And we know that
4023 cfun->stack_protect_guard is a local stack slot, so this skips
4025 x
= validize_mem (DECL_RTL (cfun
->stack_protect_guard
));
4026 y
= validize_mem (DECL_RTL (guard_decl
));
4028 /* Allow the target to copy from Y to X without leaking Y into a
4030 if (HAVE_stack_protect_set
)
4032 rtx insn
= gen_stack_protect_set (x
, y
);
4040 /* Otherwise do a straight move. */
4041 emit_move_insn (x
, y
);
4044 /* Expand code to verify the stack_protect_guard. This is invoked at
4045 the end of a function to be protected. */
4047 #ifndef HAVE_stack_protect_test
4048 # define HAVE_stack_protect_test 0
4049 # define gen_stack_protect_test(x, y, z) (gcc_unreachable (), NULL_RTX)
4053 stack_protect_epilogue (void)
4055 tree guard_decl
= targetm
.stack_protect_guard ();
4056 rtx label
= gen_label_rtx ();
4059 /* Avoid expand_expr here, because we don't want guard_decl pulled
4060 into registers unless absolutely necessary. And we know that
4061 cfun->stack_protect_guard is a local stack slot, so this skips
4063 x
= validize_mem (DECL_RTL (cfun
->stack_protect_guard
));
4064 y
= validize_mem (DECL_RTL (guard_decl
));
4066 /* Allow the target to compare Y with X without leaking either into
4068 switch (HAVE_stack_protect_test
!= 0)
4071 tmp
= gen_stack_protect_test (x
, y
, label
);
4080 emit_cmp_and_jump_insns (x
, y
, EQ
, NULL_RTX
, ptr_mode
, 1, label
);
4084 /* The noreturn predictor has been moved to the tree level. The rtl-level
4085 predictors estimate this branch about 20%, which isn't enough to get
4086 things moved out of line. Since this is the only extant case of adding
4087 a noreturn function at the rtl level, it doesn't seem worth doing ought
4088 except adding the prediction by hand. */
4089 tmp
= get_last_insn ();
4091 predict_insn_def (tmp
, PRED_NORETURN
, TAKEN
);
4093 expand_expr_stmt (targetm
.stack_protect_fail ());
4097 /* Start the RTL for a new function, and set variables used for
4099 SUBR is the FUNCTION_DECL node.
4100 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4101 the function's parameters, which must be run at any return statement. */
4104 expand_function_start (tree subr
)
4106 /* Make sure volatile mem refs aren't considered
4107 valid operands of arithmetic insns. */
4108 init_recog_no_volatile ();
4110 current_function_profile
4112 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr
));
4114 current_function_limit_stack
4115 = (stack_limit_rtx
!= NULL_RTX
&& ! DECL_NO_LIMIT_STACK (subr
));
4117 /* Make the label for return statements to jump to. Do not special
4118 case machines with special return instructions -- they will be
4119 handled later during jump, ifcvt, or epilogue creation. */
4120 return_label
= gen_label_rtx ();
4122 /* Initialize rtx used to return the value. */
4123 /* Do this before assign_parms so that we copy the struct value address
4124 before any library calls that assign parms might generate. */
4126 /* Decide whether to return the value in memory or in a register. */
4127 if (aggregate_value_p (DECL_RESULT (subr
), subr
))
4129 /* Returning something that won't go in a register. */
4130 rtx value_address
= 0;
4132 #ifdef PCC_STATIC_STRUCT_RETURN
4133 if (current_function_returns_pcc_struct
)
4135 int size
= int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr
)));
4136 value_address
= assemble_static_space (size
);
4141 rtx sv
= targetm
.calls
.struct_value_rtx (TREE_TYPE (subr
), 2);
4142 /* Expect to be passed the address of a place to store the value.
4143 If it is passed as an argument, assign_parms will take care of
4147 value_address
= gen_reg_rtx (Pmode
);
4148 emit_move_insn (value_address
, sv
);
4153 rtx x
= value_address
;
4154 if (!DECL_BY_REFERENCE (DECL_RESULT (subr
)))
4156 x
= gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr
)), x
);
4157 set_mem_attributes (x
, DECL_RESULT (subr
), 1);
4159 SET_DECL_RTL (DECL_RESULT (subr
), x
);
4162 else if (DECL_MODE (DECL_RESULT (subr
)) == VOIDmode
)
4163 /* If return mode is void, this decl rtl should not be used. */
4164 SET_DECL_RTL (DECL_RESULT (subr
), NULL_RTX
);
4167 /* Compute the return values into a pseudo reg, which we will copy
4168 into the true return register after the cleanups are done. */
4169 tree return_type
= TREE_TYPE (DECL_RESULT (subr
));
4170 if (TYPE_MODE (return_type
) != BLKmode
4171 && targetm
.calls
.return_in_msb (return_type
))
4172 /* expand_function_end will insert the appropriate padding in
4173 this case. Use the return value's natural (unpadded) mode
4174 within the function proper. */
4175 SET_DECL_RTL (DECL_RESULT (subr
),
4176 gen_reg_rtx (TYPE_MODE (return_type
)));
4179 /* In order to figure out what mode to use for the pseudo, we
4180 figure out what the mode of the eventual return register will
4181 actually be, and use that. */
4182 rtx hard_reg
= hard_function_value (return_type
, subr
, 0, 1);
4184 /* Structures that are returned in registers are not
4185 aggregate_value_p, so we may see a PARALLEL or a REG. */
4186 if (REG_P (hard_reg
))
4187 SET_DECL_RTL (DECL_RESULT (subr
),
4188 gen_reg_rtx (GET_MODE (hard_reg
)));
4191 gcc_assert (GET_CODE (hard_reg
) == PARALLEL
);
4192 SET_DECL_RTL (DECL_RESULT (subr
), gen_group_rtx (hard_reg
));
4196 /* Set DECL_REGISTER flag so that expand_function_end will copy the
4197 result to the real return register(s). */
4198 DECL_REGISTER (DECL_RESULT (subr
)) = 1;
4201 /* Initialize rtx for parameters and local variables.
4202 In some cases this requires emitting insns. */
4203 assign_parms (subr
);
4205 /* If function gets a static chain arg, store it. */
4206 if (cfun
->static_chain_decl
)
4208 tree parm
= cfun
->static_chain_decl
;
4209 rtx local
= gen_reg_rtx (Pmode
);
4211 set_decl_incoming_rtl (parm
, static_chain_incoming_rtx
, false);
4212 SET_DECL_RTL (parm
, local
);
4213 mark_reg_pointer (local
, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
4215 emit_move_insn (local
, static_chain_incoming_rtx
);
4218 /* If the function receives a non-local goto, then store the
4219 bits we need to restore the frame pointer. */
4220 if (cfun
->nonlocal_goto_save_area
)
4225 /* ??? We need to do this save early. Unfortunately here is
4226 before the frame variable gets declared. Help out... */
4227 tree var
= TREE_OPERAND (cfun
->nonlocal_goto_save_area
, 0);
4228 if (!DECL_RTL_SET_P (var
))
4231 t_save
= build4 (ARRAY_REF
, ptr_type_node
,
4232 cfun
->nonlocal_goto_save_area
,
4233 integer_zero_node
, NULL_TREE
, NULL_TREE
);
4234 r_save
= expand_expr (t_save
, NULL_RTX
, VOIDmode
, EXPAND_WRITE
);
4235 r_save
= convert_memory_address (Pmode
, r_save
);
4237 emit_move_insn (r_save
, virtual_stack_vars_rtx
);
4238 update_nonlocal_goto_save_area ();
4241 /* The following was moved from init_function_start.
4242 The move is supposed to make sdb output more accurate. */
4243 /* Indicate the beginning of the function body,
4244 as opposed to parm setup. */
4245 emit_note (NOTE_INSN_FUNCTION_BEG
);
4247 gcc_assert (NOTE_P (get_last_insn ()));
4249 parm_birth_insn
= get_last_insn ();
4251 if (current_function_profile
)
4254 PROFILE_HOOK (current_function_funcdef_no
);
4258 /* After the display initializations is where the stack checking
4260 if(flag_stack_check
)
4261 stack_check_probe_note
= emit_note (NOTE_INSN_DELETED
);
4263 /* Make sure there is a line number after the function entry setup code. */
4264 force_next_line_note ();
4267 /* Undo the effects of init_dummy_function_start. */
4269 expand_dummy_function_end (void)
4271 gcc_assert (in_dummy_function
);
4273 /* End any sequences that failed to be closed due to syntax errors. */
4274 while (in_sequence_p ())
4277 /* Outside function body, can't compute type's actual size
4278 until next function's body starts. */
4280 free_after_parsing (cfun
);
4281 free_after_compilation (cfun
);
4283 in_dummy_function
= false;
4286 /* Call DOIT for each hard register used as a return value from
4287 the current function. */
4290 diddle_return_value (void (*doit
) (rtx
, void *), void *arg
)
4292 rtx outgoing
= crtl
->return_rtx
;
4297 if (REG_P (outgoing
))
4298 (*doit
) (outgoing
, arg
);
4299 else if (GET_CODE (outgoing
) == PARALLEL
)
4303 for (i
= 0; i
< XVECLEN (outgoing
, 0); i
++)
4305 rtx x
= XEXP (XVECEXP (outgoing
, 0, i
), 0);
4307 if (REG_P (x
) && REGNO (x
) < FIRST_PSEUDO_REGISTER
)
4314 do_clobber_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
4316 emit_insn (gen_rtx_CLOBBER (VOIDmode
, reg
));
4320 clobber_return_register (void)
4322 diddle_return_value (do_clobber_return_reg
, NULL
);
4324 /* In case we do use pseudo to return value, clobber it too. */
4325 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
4327 tree decl_result
= DECL_RESULT (current_function_decl
);
4328 rtx decl_rtl
= DECL_RTL (decl_result
);
4329 if (REG_P (decl_rtl
) && REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
)
4331 do_clobber_return_reg (decl_rtl
, NULL
);
4337 do_use_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
4339 emit_insn (gen_rtx_USE (VOIDmode
, reg
));
4343 use_return_register (void)
4345 diddle_return_value (do_use_return_reg
, NULL
);
4348 /* Possibly warn about unused parameters. */
4350 do_warn_unused_parameter (tree fn
)
4354 for (decl
= DECL_ARGUMENTS (fn
);
4355 decl
; decl
= TREE_CHAIN (decl
))
4356 if (!TREE_USED (decl
) && TREE_CODE (decl
) == PARM_DECL
4357 && DECL_NAME (decl
) && !DECL_ARTIFICIAL (decl
)
4358 && !TREE_NO_WARNING (decl
))
4359 warning (OPT_Wunused_parameter
, "unused parameter %q+D", decl
);
4362 static GTY(()) rtx initial_trampoline
;
4364 /* Generate RTL for the end of the current function. */
4367 expand_function_end (void)
4371 /* If arg_pointer_save_area was referenced only from a nested
4372 function, we will not have initialized it yet. Do that now. */
4373 if (arg_pointer_save_area
&& ! cfun
->arg_pointer_save_area_init
)
4374 get_arg_pointer_save_area ();
4376 /* If we are doing stack checking and this function makes calls,
4377 do a stack probe at the start of the function to ensure we have enough
4378 space for another stack frame. */
4379 if (flag_stack_check
&& ! STACK_CHECK_BUILTIN
)
4383 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
4387 probe_stack_range (STACK_CHECK_PROTECT
,
4388 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE
));
4391 emit_insn_before (seq
, stack_check_probe_note
);
4396 /* End any sequences that failed to be closed due to syntax errors. */
4397 while (in_sequence_p ())
4400 clear_pending_stack_adjust ();
4401 do_pending_stack_adjust ();
4403 /* Output a linenumber for the end of the function.
4404 SDB depends on this. */
4405 force_next_line_note ();
4406 set_curr_insn_source_location (input_location
);
4408 /* Before the return label (if any), clobber the return
4409 registers so that they are not propagated live to the rest of
4410 the function. This can only happen with functions that drop
4411 through; if there had been a return statement, there would
4412 have either been a return rtx, or a jump to the return label.
4414 We delay actual code generation after the current_function_value_rtx
4416 clobber_after
= get_last_insn ();
4418 /* Output the label for the actual return from the function. */
4419 emit_label (return_label
);
4421 if (USING_SJLJ_EXCEPTIONS
)
4423 /* Let except.c know where it should emit the call to unregister
4424 the function context for sjlj exceptions. */
4425 if (flag_exceptions
)
4426 sjlj_emit_function_exit_after (get_last_insn ());
4430 /* We want to ensure that instructions that may trap are not
4431 moved into the epilogue by scheduling, because we don't
4432 always emit unwind information for the epilogue. */
4433 if (flag_non_call_exceptions
)
4434 emit_insn (gen_blockage ());
4437 /* If this is an implementation of throw, do what's necessary to
4438 communicate between __builtin_eh_return and the epilogue. */
4439 expand_eh_return ();
4441 /* If scalar return value was computed in a pseudo-reg, or was a named
4442 return value that got dumped to the stack, copy that to the hard
4444 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
4446 tree decl_result
= DECL_RESULT (current_function_decl
);
4447 rtx decl_rtl
= DECL_RTL (decl_result
);
4449 if (REG_P (decl_rtl
)
4450 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
4451 : DECL_REGISTER (decl_result
))
4453 rtx real_decl_rtl
= crtl
->return_rtx
;
4455 /* This should be set in assign_parms. */
4456 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl
));
4458 /* If this is a BLKmode structure being returned in registers,
4459 then use the mode computed in expand_return. Note that if
4460 decl_rtl is memory, then its mode may have been changed,
4461 but that crtl->return_rtx has not. */
4462 if (GET_MODE (real_decl_rtl
) == BLKmode
)
4463 PUT_MODE (real_decl_rtl
, GET_MODE (decl_rtl
));
4465 /* If a non-BLKmode return value should be padded at the least
4466 significant end of the register, shift it left by the appropriate
4467 amount. BLKmode results are handled using the group load/store
4469 if (TYPE_MODE (TREE_TYPE (decl_result
)) != BLKmode
4470 && targetm
.calls
.return_in_msb (TREE_TYPE (decl_result
)))
4472 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl
),
4473 REGNO (real_decl_rtl
)),
4475 shift_return_value (GET_MODE (decl_rtl
), true, real_decl_rtl
);
4477 /* If a named return value dumped decl_return to memory, then
4478 we may need to re-do the PROMOTE_MODE signed/unsigned
4480 else if (GET_MODE (real_decl_rtl
) != GET_MODE (decl_rtl
))
4482 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (decl_result
));
4484 if (targetm
.calls
.promote_function_return (TREE_TYPE (current_function_decl
)))
4485 promote_mode (TREE_TYPE (decl_result
), GET_MODE (decl_rtl
),
4488 convert_move (real_decl_rtl
, decl_rtl
, unsignedp
);
4490 else if (GET_CODE (real_decl_rtl
) == PARALLEL
)
4492 /* If expand_function_start has created a PARALLEL for decl_rtl,
4493 move the result to the real return registers. Otherwise, do
4494 a group load from decl_rtl for a named return. */
4495 if (GET_CODE (decl_rtl
) == PARALLEL
)
4496 emit_group_move (real_decl_rtl
, decl_rtl
);
4498 emit_group_load (real_decl_rtl
, decl_rtl
,
4499 TREE_TYPE (decl_result
),
4500 int_size_in_bytes (TREE_TYPE (decl_result
)));
4502 /* In the case of complex integer modes smaller than a word, we'll
4503 need to generate some non-trivial bitfield insertions. Do that
4504 on a pseudo and not the hard register. */
4505 else if (GET_CODE (decl_rtl
) == CONCAT
4506 && GET_MODE_CLASS (GET_MODE (decl_rtl
)) == MODE_COMPLEX_INT
4507 && GET_MODE_BITSIZE (GET_MODE (decl_rtl
)) <= BITS_PER_WORD
)
4509 int old_generating_concat_p
;
4512 old_generating_concat_p
= generating_concat_p
;
4513 generating_concat_p
= 0;
4514 tmp
= gen_reg_rtx (GET_MODE (decl_rtl
));
4515 generating_concat_p
= old_generating_concat_p
;
4517 emit_move_insn (tmp
, decl_rtl
);
4518 emit_move_insn (real_decl_rtl
, tmp
);
4521 emit_move_insn (real_decl_rtl
, decl_rtl
);
4525 /* If returning a structure, arrange to return the address of the value
4526 in a place where debuggers expect to find it.
4528 If returning a structure PCC style,
4529 the caller also depends on this value.
4530 And current_function_returns_pcc_struct is not necessarily set. */
4531 if (current_function_returns_struct
4532 || current_function_returns_pcc_struct
)
4534 rtx value_address
= DECL_RTL (DECL_RESULT (current_function_decl
));
4535 tree type
= TREE_TYPE (DECL_RESULT (current_function_decl
));
4538 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl
)))
4539 type
= TREE_TYPE (type
);
4541 value_address
= XEXP (value_address
, 0);
4543 outgoing
= targetm
.calls
.function_value (build_pointer_type (type
),
4544 current_function_decl
, true);
4546 /* Mark this as a function return value so integrate will delete the
4547 assignment and USE below when inlining this function. */
4548 REG_FUNCTION_VALUE_P (outgoing
) = 1;
4550 /* The address may be ptr_mode and OUTGOING may be Pmode. */
4551 value_address
= convert_memory_address (GET_MODE (outgoing
),
4554 emit_move_insn (outgoing
, value_address
);
4556 /* Show return register used to hold result (in this case the address
4558 crtl
->return_rtx
= outgoing
;
4561 /* Emit the actual code to clobber return register. */
4566 clobber_return_register ();
4567 expand_naked_return ();
4571 emit_insn_after (seq
, clobber_after
);
4574 /* Output the label for the naked return from the function. */
4575 emit_label (naked_return_label
);
4577 /* @@@ This is a kludge. We want to ensure that instructions that
4578 may trap are not moved into the epilogue by scheduling, because
4579 we don't always emit unwind information for the epilogue. */
4580 if (! USING_SJLJ_EXCEPTIONS
&& flag_non_call_exceptions
)
4581 emit_insn (gen_blockage ());
4583 /* If stack protection is enabled for this function, check the guard. */
4584 if (cfun
->stack_protect_guard
)
4585 stack_protect_epilogue ();
4587 /* If we had calls to alloca, and this machine needs
4588 an accurate stack pointer to exit the function,
4589 insert some code to save and restore the stack pointer. */
4590 if (! EXIT_IGNORE_STACK
4591 && current_function_calls_alloca
)
4595 emit_stack_save (SAVE_FUNCTION
, &tem
, parm_birth_insn
);
4596 emit_stack_restore (SAVE_FUNCTION
, tem
, NULL_RTX
);
4599 /* ??? This should no longer be necessary since stupid is no longer with
4600 us, but there are some parts of the compiler (eg reload_combine, and
4601 sh mach_dep_reorg) that still try and compute their own lifetime info
4602 instead of using the general framework. */
4603 use_return_register ();
4607 get_arg_pointer_save_area (void)
4609 rtx ret
= arg_pointer_save_area
;
4613 ret
= assign_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0);
4614 arg_pointer_save_area
= ret
;
4617 if (! cfun
->arg_pointer_save_area_init
)
4621 /* Save the arg pointer at the beginning of the function. The
4622 generated stack slot may not be a valid memory address, so we
4623 have to check it and fix it if necessary. */
4625 emit_move_insn (validize_mem (ret
), virtual_incoming_args_rtx
);
4629 push_topmost_sequence ();
4630 emit_insn_after (seq
, entry_of_function ());
4631 pop_topmost_sequence ();
4637 /* Extend a vector that records the INSN_UIDs of INSNS
4638 (a list of one or more insns). */
4641 record_insns (rtx insns
, VEC(int,heap
) **vecp
)
4645 for (tmp
= insns
; tmp
!= NULL_RTX
; tmp
= NEXT_INSN (tmp
))
4646 VEC_safe_push (int, heap
, *vecp
, INSN_UID (tmp
));
4649 /* Set the locator of the insn chain starting at INSN to LOC. */
4651 set_insn_locators (rtx insn
, int loc
)
4653 while (insn
!= NULL_RTX
)
4656 INSN_LOCATOR (insn
) = loc
;
4657 insn
= NEXT_INSN (insn
);
4661 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
4662 be running after reorg, SEQUENCE rtl is possible. */
4665 contains (const_rtx insn
, VEC(int,heap
) **vec
)
4669 if (NONJUMP_INSN_P (insn
)
4670 && GET_CODE (PATTERN (insn
)) == SEQUENCE
)
4673 for (i
= XVECLEN (PATTERN (insn
), 0) - 1; i
>= 0; i
--)
4674 for (j
= VEC_length (int, *vec
) - 1; j
>= 0; --j
)
4675 if (INSN_UID (XVECEXP (PATTERN (insn
), 0, i
))
4676 == VEC_index (int, *vec
, j
))
4682 for (j
= VEC_length (int, *vec
) - 1; j
>= 0; --j
)
4683 if (INSN_UID (insn
) == VEC_index (int, *vec
, j
))
4690 prologue_epilogue_contains (const_rtx insn
)
4692 if (contains (insn
, &prologue
))
4694 if (contains (insn
, &epilogue
))
4700 sibcall_epilogue_contains (const_rtx insn
)
4702 if (sibcall_epilogue
)
4703 return contains (insn
, &sibcall_epilogue
);
4708 /* Insert gen_return at the end of block BB. This also means updating
4709 block_for_insn appropriately. */
4712 emit_return_into_block (basic_block bb
)
4714 emit_jump_insn_after (gen_return (), BB_END (bb
));
4716 #endif /* HAVE_return */
4718 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
4719 this into place with notes indicating where the prologue ends and where
4720 the epilogue begins. Update the basic block information when possible. */
4723 thread_prologue_and_epilogue_insns (void)
4727 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
4730 #if defined (HAVE_epilogue) || defined(HAVE_return)
4731 rtx epilogue_end
= NULL_RTX
;
4735 #ifdef HAVE_prologue
4739 seq
= gen_prologue ();
4742 /* Insert an explicit USE for the frame pointer
4743 if the profiling is on and the frame pointer is required. */
4744 if (current_function_profile
&& frame_pointer_needed
)
4745 emit_insn (gen_rtx_USE (VOIDmode
, hard_frame_pointer_rtx
));
4747 /* Retain a map of the prologue insns. */
4748 record_insns (seq
, &prologue
);
4749 emit_note (NOTE_INSN_PROLOGUE_END
);
4751 #ifndef PROFILE_BEFORE_PROLOGUE
4752 /* Ensure that instructions are not moved into the prologue when
4753 profiling is on. The call to the profiling routine can be
4754 emitted within the live range of a call-clobbered register. */
4755 if (current_function_profile
)
4756 emit_insn (gen_blockage ());
4761 set_insn_locators (seq
, prologue_locator
);
4763 /* Can't deal with multiple successors of the entry block
4764 at the moment. Function should always have at least one
4766 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR
));
4768 insert_insn_on_edge (seq
, single_succ_edge (ENTRY_BLOCK_PTR
));
4773 /* If the exit block has no non-fake predecessors, we don't need
4775 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
4776 if ((e
->flags
& EDGE_FAKE
) == 0)
4782 if (optimize
&& HAVE_return
)
4784 /* If we're allowed to generate a simple return instruction,
4785 then by definition we don't need a full epilogue. Examine
4786 the block that falls through to EXIT. If it does not
4787 contain any code, examine its predecessors and try to
4788 emit (conditional) return instructions. */
4793 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
4794 if (e
->flags
& EDGE_FALLTHRU
)
4800 /* Verify that there are no active instructions in the last block. */
4801 label
= BB_END (last
);
4802 while (label
&& !LABEL_P (label
))
4804 if (active_insn_p (label
))
4806 label
= PREV_INSN (label
);
4809 if (BB_HEAD (last
) == label
&& LABEL_P (label
))
4813 for (ei2
= ei_start (last
->preds
); (e
= ei_safe_edge (ei2
)); )
4815 basic_block bb
= e
->src
;
4818 if (bb
== ENTRY_BLOCK_PTR
)
4825 if (!JUMP_P (jump
) || JUMP_LABEL (jump
) != label
)
4831 /* If we have an unconditional jump, we can replace that
4832 with a simple return instruction. */
4833 if (simplejump_p (jump
))
4835 emit_return_into_block (bb
);
4839 /* If we have a conditional jump, we can try to replace
4840 that with a conditional return instruction. */
4841 else if (condjump_p (jump
))
4843 if (! redirect_jump (jump
, 0, 0))
4849 /* If this block has only one successor, it both jumps
4850 and falls through to the fallthru block, so we can't
4852 if (single_succ_p (bb
))
4864 /* Fix up the CFG for the successful change we just made. */
4865 redirect_edge_succ (e
, EXIT_BLOCK_PTR
);
4868 /* Emit a return insn for the exit fallthru block. Whether
4869 this is still reachable will be determined later. */
4871 emit_barrier_after (BB_END (last
));
4872 emit_return_into_block (last
);
4873 epilogue_end
= BB_END (last
);
4874 single_succ_edge (last
)->flags
&= ~EDGE_FALLTHRU
;
4879 /* Find the edge that falls through to EXIT. Other edges may exist
4880 due to RETURN instructions, but those don't need epilogues.
4881 There really shouldn't be a mixture -- either all should have
4882 been converted or none, however... */
4884 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
4885 if (e
->flags
& EDGE_FALLTHRU
)
4890 #ifdef HAVE_epilogue
4894 epilogue_end
= emit_note (NOTE_INSN_EPILOGUE_BEG
);
4895 seq
= gen_epilogue ();
4896 emit_jump_insn (seq
);
4898 /* Retain a map of the epilogue insns. */
4899 record_insns (seq
, &epilogue
);
4900 set_insn_locators (seq
, epilogue_locator
);
4905 insert_insn_on_edge (seq
, e
);
4913 if (! next_active_insn (BB_END (e
->src
)))
4915 /* We have a fall-through edge to the exit block, the source is not
4916 at the end of the function, and there will be an assembler epilogue
4917 at the end of the function.
4918 We can't use force_nonfallthru here, because that would try to
4919 use return. Inserting a jump 'by hand' is extremely messy, so
4920 we take advantage of cfg_layout_finalize using
4921 fixup_fallthru_exit_predecessor. */
4922 cfg_layout_initialize (0);
4923 FOR_EACH_BB (cur_bb
)
4924 if (cur_bb
->index
>= NUM_FIXED_BLOCKS
4925 && cur_bb
->next_bb
->index
>= NUM_FIXED_BLOCKS
)
4926 cur_bb
->aux
= cur_bb
->next_bb
;
4927 cfg_layout_finalize ();
4933 commit_edge_insertions ();
4935 /* The epilogue insns we inserted may cause the exit edge to no longer
4937 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
4939 if (((e
->flags
& EDGE_FALLTHRU
) != 0)
4940 && returnjump_p (BB_END (e
->src
)))
4941 e
->flags
&= ~EDGE_FALLTHRU
;
4945 #ifdef HAVE_sibcall_epilogue
4946 /* Emit sibling epilogues before any sibling call sites. */
4947 for (ei
= ei_start (EXIT_BLOCK_PTR
->preds
); (e
= ei_safe_edge (ei
)); )
4949 basic_block bb
= e
->src
;
4950 rtx insn
= BB_END (bb
);
4953 || ! SIBLING_CALL_P (insn
))
4960 emit_insn (gen_sibcall_epilogue ());
4964 /* Retain a map of the epilogue insns. Used in life analysis to
4965 avoid getting rid of sibcall epilogue insns. Do this before we
4966 actually emit the sequence. */
4967 record_insns (seq
, &sibcall_epilogue
);
4968 set_insn_locators (seq
, epilogue_locator
);
4970 emit_insn_before (seq
, insn
);
4975 #ifdef HAVE_epilogue
4980 /* Similarly, move any line notes that appear after the epilogue.
4981 There is no need, however, to be quite so anal about the existence
4982 of such a note. Also possibly move
4983 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
4985 for (insn
= epilogue_end
; insn
; insn
= next
)
4987 next
= NEXT_INSN (insn
);
4989 && (NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
))
4990 reorder_insns (insn
, insn
, PREV_INSN (epilogue_end
));
4995 /* Threading the prologue and epilogue changes the artificial refs
4996 in the entry and exit blocks. */
4997 epilogue_completed
= 1;
4998 df_update_entry_exit_and_calls ();
5001 /* Reposition the prologue-end and epilogue-begin notes after instruction
5002 scheduling and delayed branch scheduling. */
5005 reposition_prologue_and_epilogue_notes (void)
5007 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
5008 rtx insn
, last
, note
;
5011 if ((len
= VEC_length (int, prologue
)) > 0)
5015 /* Scan from the beginning until we reach the last prologue insn.
5016 We apparently can't depend on basic_block_{head,end} after
5018 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
5022 if (NOTE_KIND (insn
) == NOTE_INSN_PROLOGUE_END
)
5025 else if (contains (insn
, &prologue
))
5035 /* Find the prologue-end note if we haven't already, and
5036 move it to just after the last prologue insn. */
5039 for (note
= last
; (note
= NEXT_INSN (note
));)
5041 && NOTE_KIND (note
) == NOTE_INSN_PROLOGUE_END
)
5045 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
5047 last
= NEXT_INSN (last
);
5048 reorder_insns (note
, note
, last
);
5052 if ((len
= VEC_length (int, epilogue
)) > 0)
5056 /* Scan from the end until we reach the first epilogue insn.
5057 We apparently can't depend on basic_block_{head,end} after
5059 for (insn
= get_last_insn (); insn
; insn
= PREV_INSN (insn
))
5063 if (NOTE_KIND (insn
) == NOTE_INSN_EPILOGUE_BEG
)
5066 else if (contains (insn
, &epilogue
))
5076 /* Find the epilogue-begin note if we haven't already, and
5077 move it to just before the first epilogue insn. */
5080 for (note
= insn
; (note
= PREV_INSN (note
));)
5082 && NOTE_KIND (note
) == NOTE_INSN_EPILOGUE_BEG
)
5086 if (PREV_INSN (last
) != note
)
5087 reorder_insns (note
, note
, PREV_INSN (last
));
5090 #endif /* HAVE_prologue or HAVE_epilogue */
5093 /* Returns the name of the current function. */
5095 current_function_name (void)
5097 return lang_hooks
.decl_printable_name (cfun
->decl
, 2);
5100 /* Returns the raw (mangled) name of the current function. */
5102 current_function_assembler_name (void)
5104 return IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (cfun
->decl
));
5109 rest_of_handle_check_leaf_regs (void)
5111 #ifdef LEAF_REGISTERS
5112 current_function_uses_only_leaf_regs
5113 = optimize
> 0 && only_leaf_regs_used () && leaf_function_p ();
5118 /* Insert a TYPE into the used types hash table of CFUN. */
5120 used_types_insert_helper (tree type
, struct function
*func
)
5122 if (type
!= NULL
&& func
!= NULL
)
5126 if (func
->used_types_hash
== NULL
)
5127 func
->used_types_hash
= htab_create_ggc (37, htab_hash_pointer
,
5128 htab_eq_pointer
, NULL
);
5129 slot
= htab_find_slot (func
->used_types_hash
, type
, INSERT
);
5135 /* Given a type, insert it into the used hash table in cfun. */
5137 used_types_insert (tree t
)
5139 while (POINTER_TYPE_P (t
) || TREE_CODE (t
) == ARRAY_TYPE
)
5141 t
= TYPE_MAIN_VARIANT (t
);
5142 if (debug_info_level
> DINFO_LEVEL_NONE
)
5143 used_types_insert_helper (t
, cfun
);
5146 struct rtl_opt_pass pass_leaf_regs
=
5152 rest_of_handle_check_leaf_regs
, /* execute */
5155 0, /* static_pass_number */
5157 0, /* properties_required */
5158 0, /* properties_provided */
5159 0, /* properties_destroyed */
5160 0, /* todo_flags_start */
5161 0 /* todo_flags_finish */
5166 rest_of_handle_thread_prologue_and_epilogue (void)
5169 cleanup_cfg (CLEANUP_EXPENSIVE
);
5170 /* On some machines, the prologue and epilogue code, or parts thereof,
5171 can be represented as RTL. Doing so lets us schedule insns between
5172 it and the rest of the code and also allows delayed branch
5173 scheduling to operate in the epilogue. */
5175 thread_prologue_and_epilogue_insns ();
5179 struct rtl_opt_pass pass_thread_prologue_and_epilogue
=
5183 "pro_and_epilogue", /* name */
5185 rest_of_handle_thread_prologue_and_epilogue
, /* execute */
5188 0, /* static_pass_number */
5189 TV_THREAD_PROLOGUE_AND_EPILOGUE
, /* tv_id */
5190 0, /* properties_required */
5191 0, /* properties_provided */
5192 0, /* properties_destroyed */
5193 TODO_verify_flow
, /* todo_flags_start */
5196 TODO_df_finish
| TODO_verify_rtl_sharing
|
5197 TODO_ggc_collect
/* todo_flags_finish */
5202 /* This mini-pass fixes fall-out from SSA in asm statements that have
5203 in-out constraints. Say you start with
5206 asm ("": "+mr" (inout));
5209 which is transformed very early to use explicit output and match operands:
5212 asm ("": "=mr" (inout) : "0" (inout));
5215 Or, after SSA and copyprop,
5217 asm ("": "=mr" (inout_2) : "0" (inout_1));
5220 Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
5221 they represent two separate values, so they will get different pseudo
5222 registers during expansion. Then, since the two operands need to match
5223 per the constraints, but use different pseudo registers, reload can
5224 only register a reload for these operands. But reloads can only be
5225 satisfied by hardregs, not by memory, so we need a register for this
5226 reload, just because we are presented with non-matching operands.
5227 So, even though we allow memory for this operand, no memory can be
5228 used for it, just because the two operands don't match. This can
5229 cause reload failures on register-starved targets.
5231 So it's a symptom of reload not being able to use memory for reloads
5232 or, alternatively it's also a symptom of both operands not coming into
5233 reload as matching (in which case the pseudo could go to memory just
5234 fine, as the alternative allows it, and no reload would be necessary).
5235 We fix the latter problem here, by transforming
5237 asm ("": "=mr" (inout_2) : "0" (inout_1));
5242 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
5245 match_asm_constraints_1 (rtx insn
, rtx
*p_sets
, int noutputs
)
5248 bool changed
= false;
5249 rtx op
= SET_SRC (p_sets
[0]);
5250 int ninputs
= ASM_OPERANDS_INPUT_LENGTH (op
);
5251 rtvec inputs
= ASM_OPERANDS_INPUT_VEC (op
);
5252 bool *output_matched
= alloca (noutputs
* sizeof (bool));
5254 memset (output_matched
, 0, noutputs
* sizeof (bool));
5255 for (i
= 0; i
< ninputs
; i
++)
5257 rtx input
, output
, insns
;
5258 const char *constraint
= ASM_OPERANDS_INPUT_CONSTRAINT (op
, i
);
5262 match
= strtoul (constraint
, &end
, 10);
5263 if (end
== constraint
)
5266 gcc_assert (match
< noutputs
);
5267 output
= SET_DEST (p_sets
[match
]);
5268 input
= RTVEC_ELT (inputs
, i
);
5269 /* Only do the transformation for pseudos. */
5270 if (! REG_P (output
)
5271 || rtx_equal_p (output
, input
)
5272 || (GET_MODE (input
) != VOIDmode
5273 && GET_MODE (input
) != GET_MODE (output
)))
5276 /* We can't do anything if the output is also used as input,
5277 as we're going to overwrite it. */
5278 for (j
= 0; j
< ninputs
; j
++)
5279 if (reg_overlap_mentioned_p (output
, RTVEC_ELT (inputs
, j
)))
5284 /* Avoid changing the same input several times. For
5285 asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
5286 only change in once (to out1), rather than changing it
5287 first to out1 and afterwards to out2. */
5290 for (j
= 0; j
< noutputs
; j
++)
5291 if (output_matched
[j
] && input
== SET_DEST (p_sets
[j
]))
5296 output_matched
[match
] = true;
5299 emit_move_insn (output
, input
);
5300 insns
= get_insns ();
5302 emit_insn_before (insns
, insn
);
5304 /* Now replace all mentions of the input with output. We can't
5305 just replace the occurence in inputs[i], as the register might
5306 also be used in some other input (or even in an address of an
5307 output), which would mean possibly increasing the number of
5308 inputs by one (namely 'output' in addition), which might pose
5309 a too complicated problem for reload to solve. E.g. this situation:
5311 asm ("" : "=r" (output), "=m" (input) : "0" (input))
5313 Here 'input' is used in two occurrences as input (once for the
5314 input operand, once for the address in the second output operand).
5315 If we would replace only the occurence of the input operand (to
5316 make the matching) we would be left with this:
5319 asm ("" : "=r" (output), "=m" (input) : "0" (output))
5321 Now we suddenly have two different input values (containing the same
5322 value, but different pseudos) where we formerly had only one.
5323 With more complicated asms this might lead to reload failures
5324 which wouldn't have happen without this pass. So, iterate over
5325 all operands and replace all occurrences of the register used. */
5326 for (j
= 0; j
< noutputs
; j
++)
5327 if (!rtx_equal_p (SET_DEST (p_sets
[j
]), input
)
5328 && reg_overlap_mentioned_p (input
, SET_DEST (p_sets
[j
])))
5329 SET_DEST (p_sets
[j
]) = replace_rtx (SET_DEST (p_sets
[j
]),
5331 for (j
= 0; j
< ninputs
; j
++)
5332 if (reg_overlap_mentioned_p (input
, RTVEC_ELT (inputs
, j
)))
5333 RTVEC_ELT (inputs
, j
) = replace_rtx (RTVEC_ELT (inputs
, j
),
5340 df_insn_rescan (insn
);
5344 rest_of_match_asm_constraints (void)
5347 rtx insn
, pat
, *p_sets
;
5350 if (!cfun
->has_asm_statement
)
5353 df_set_flags (DF_DEFER_INSN_RESCAN
);
5356 FOR_BB_INSNS (bb
, insn
)
5361 pat
= PATTERN (insn
);
5362 if (GET_CODE (pat
) == PARALLEL
)
5363 p_sets
= &XVECEXP (pat
, 0, 0), noutputs
= XVECLEN (pat
, 0);
5364 else if (GET_CODE (pat
) == SET
)
5365 p_sets
= &PATTERN (insn
), noutputs
= 1;
5369 if (GET_CODE (*p_sets
) == SET
5370 && GET_CODE (SET_SRC (*p_sets
)) == ASM_OPERANDS
)
5371 match_asm_constraints_1 (insn
, p_sets
, noutputs
);
5375 return TODO_df_finish
;
5378 struct rtl_opt_pass pass_match_asm_constraints
=
5382 "asmcons", /* name */
5384 rest_of_match_asm_constraints
, /* execute */
5387 0, /* static_pass_number */
5389 0, /* properties_required */
5390 0, /* properties_provided */
5391 0, /* properties_destroyed */
5392 0, /* todo_flags_start */
5393 TODO_dump_func
/* todo_flags_finish */
5398 #include "gt-function.h"