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
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 2, 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 COPYING. If not, write to the Free
20 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
23 /* This file handles the generation of rtl code from tree structure
24 at the level of the function as a whole.
25 It creates the rtl expressions for parameters and auto variables
26 and has full responsibility for allocating stack slots.
28 `expand_function_start' is called at the beginning of a function,
29 before the function body is parsed, and `expand_function_end' is
30 called after parsing the body.
32 Call `assign_stack_local' to allocate a stack slot for a local variable.
33 This is usually done during the RTL generation for the function body,
34 but it can also be done in the reload pass when a pseudo-register does
35 not get a hard register. */
39 #include "coretypes.h"
50 #include "hard-reg-set.h"
51 #include "insn-config.h"
54 #include "basic-block.h"
59 #include "integrate.h"
60 #include "langhooks.h"
62 #include "cfglayout.h"
63 #include "tree-gimple.h"
64 #include "tree-pass.h"
67 #ifndef LOCAL_ALIGNMENT
68 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
71 #ifndef STACK_ALIGNMENT_NEEDED
72 #define STACK_ALIGNMENT_NEEDED 1
75 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
77 /* Some systems use __main in a way incompatible with its use in gcc, in these
78 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
79 give the same symbol without quotes for an alternative entry point. You
80 must define both, or neither. */
82 #define NAME__MAIN "__main"
85 /* Round a value to the lowest integer less than it that is a multiple of
86 the required alignment. Avoid using division in case the value is
87 negative. Assume the alignment is a power of two. */
88 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
90 /* Similar, but round to the next highest integer that meets the
92 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
94 /* Nonzero if function being compiled doesn't contain any calls
95 (ignoring the prologue and epilogue). This is set prior to
96 local register allocation and is valid for the remaining
98 int current_function_is_leaf
;
100 /* Nonzero if function being compiled doesn't modify the stack pointer
101 (ignoring the prologue and epilogue). This is only valid after
102 life_analysis has run. */
103 int current_function_sp_is_unchanging
;
105 /* Nonzero if the function being compiled is a leaf function which only
106 uses leaf registers. This is valid after reload (specifically after
107 sched2) and is useful only if the port defines LEAF_REGISTERS. */
108 int current_function_uses_only_leaf_regs
;
110 /* Nonzero once virtual register instantiation has been done.
111 assign_stack_local uses frame_pointer_rtx when this is nonzero.
112 calls.c:emit_library_call_value_1 uses it to set up
113 post-instantiation libcalls. */
114 int virtuals_instantiated
;
116 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
117 static GTY(()) int funcdef_no
;
119 /* These variables hold pointers to functions to create and destroy
120 target specific, per-function data structures. */
121 struct machine_function
* (*init_machine_status
) (void);
123 /* The currently compiled function. */
124 struct function
*cfun
= 0;
127 DEF_VEC_ALLOC_I(int,heap
);
129 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
130 static VEC(int,heap
) *prologue
;
131 static VEC(int,heap
) *epilogue
;
133 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
135 static VEC(int,heap
) *sibcall_epilogue
;
137 /* In order to evaluate some expressions, such as function calls returning
138 structures in memory, we need to temporarily allocate stack locations.
139 We record each allocated temporary in the following structure.
141 Associated with each temporary slot is a nesting level. When we pop up
142 one level, all temporaries associated with the previous level are freed.
143 Normally, all temporaries are freed after the execution of the statement
144 in which they were created. However, if we are inside a ({...}) grouping,
145 the result may be in a temporary and hence must be preserved. If the
146 result could be in a temporary, we preserve it if we can determine which
147 one it is in. If we cannot determine which temporary may contain the
148 result, all temporaries are preserved. A temporary is preserved by
149 pretending it was allocated at the previous nesting level.
151 Automatic variables are also assigned temporary slots, at the nesting
152 level where they are defined. They are marked a "kept" so that
153 free_temp_slots will not free them. */
155 struct temp_slot
GTY(())
157 /* Points to next temporary slot. */
158 struct temp_slot
*next
;
159 /* Points to previous temporary slot. */
160 struct temp_slot
*prev
;
162 /* The rtx to used to reference the slot. */
164 /* The rtx used to represent the address if not the address of the
165 slot above. May be an EXPR_LIST if multiple addresses exist. */
167 /* The alignment (in bits) of the slot. */
169 /* The size, in units, of the slot. */
171 /* The type of the object in the slot, or zero if it doesn't correspond
172 to a type. We use this to determine whether a slot can be reused.
173 It can be reused if objects of the type of the new slot will always
174 conflict with objects of the type of the old slot. */
176 /* Nonzero if this temporary is currently in use. */
178 /* Nonzero if this temporary has its address taken. */
180 /* Nesting level at which this slot is being used. */
182 /* Nonzero if this should survive a call to free_temp_slots. */
184 /* The offset of the slot from the frame_pointer, including extra space
185 for alignment. This info is for combine_temp_slots. */
186 HOST_WIDE_INT base_offset
;
187 /* The size of the slot, including extra space for alignment. This
188 info is for combine_temp_slots. */
189 HOST_WIDE_INT full_size
;
192 /* Forward declarations. */
194 static rtx
assign_stack_local_1 (enum machine_mode
, HOST_WIDE_INT
, int,
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 void reorder_fix_fragments (tree
);
201 static int all_blocks (tree
, tree
*);
202 static tree
*get_block_vector (tree
, int *);
203 extern tree
debug_find_var_in_block_tree (tree
, tree
);
204 /* We always define `record_insns' even if it's not used so that we
205 can always export `prologue_epilogue_contains'. */
206 static void record_insns (rtx
, VEC(int,heap
) **) ATTRIBUTE_UNUSED
;
207 static int contains (rtx
, VEC(int,heap
) **);
209 static void emit_return_into_block (basic_block
, rtx
);
211 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
212 static rtx
keep_stack_depressed (rtx
);
214 static void prepare_function_start (tree
);
215 static void do_clobber_return_reg (rtx
, void *);
216 static void do_use_return_reg (rtx
, void *);
217 static void set_insn_locators (rtx
, int) ATTRIBUTE_UNUSED
;
219 /* Pointer to chain of `struct function' for containing functions. */
220 struct function
*outer_function_chain
;
222 /* Given a function decl for a containing function,
223 return the `struct function' for it. */
226 find_function_data (tree decl
)
230 for (p
= outer_function_chain
; p
; p
= p
->outer
)
237 /* Save the current context for compilation of a nested function.
238 This is called from language-specific code. The caller should use
239 the enter_nested langhook to save any language-specific state,
240 since this function knows only about language-independent
244 push_function_context_to (tree context ATTRIBUTE_UNUSED
)
249 init_dummy_function_start ();
252 p
->outer
= outer_function_chain
;
253 outer_function_chain
= p
;
255 lang_hooks
.function
.enter_nested (p
);
261 push_function_context (void)
263 push_function_context_to (current_function_decl
);
266 /* Restore the last saved context, at the end of a nested function.
267 This function is called from language-specific code. */
270 pop_function_context_from (tree context ATTRIBUTE_UNUSED
)
272 struct function
*p
= outer_function_chain
;
275 outer_function_chain
= p
->outer
;
277 current_function_decl
= p
->decl
;
279 lang_hooks
.function
.leave_nested (p
);
281 /* Reset variables that have known state during rtx generation. */
282 virtuals_instantiated
= 0;
283 generating_concat_p
= 1;
287 pop_function_context (void)
289 pop_function_context_from (current_function_decl
);
292 /* Clear out all parts of the state in F that can safely be discarded
293 after the function has been parsed, but not compiled, to let
294 garbage collection reclaim the memory. */
297 free_after_parsing (struct function
*f
)
299 /* f->expr->forced_labels is used by code generation. */
300 /* f->emit->regno_reg_rtx is used by code generation. */
301 /* f->varasm is used by code generation. */
302 /* f->eh->eh_return_stub_label is used by code generation. */
304 lang_hooks
.function
.final (f
);
307 /* Clear out all parts of the state in F that can safely be discarded
308 after the function has been compiled, to let garbage collection
309 reclaim the memory. */
312 free_after_compilation (struct function
*f
)
314 VEC_free (int, heap
, prologue
);
315 VEC_free (int, heap
, epilogue
);
316 VEC_free (int, heap
, sibcall_epilogue
);
325 f
->x_avail_temp_slots
= NULL
;
326 f
->x_used_temp_slots
= NULL
;
327 f
->arg_offset_rtx
= NULL
;
328 f
->return_rtx
= NULL
;
329 f
->internal_arg_pointer
= NULL
;
330 f
->x_nonlocal_goto_handler_labels
= NULL
;
331 f
->x_return_label
= NULL
;
332 f
->x_naked_return_label
= NULL
;
333 f
->x_stack_slot_list
= NULL
;
334 f
->x_tail_recursion_reentry
= NULL
;
335 f
->x_arg_pointer_save_area
= NULL
;
336 f
->x_parm_birth_insn
= NULL
;
337 f
->original_arg_vector
= NULL
;
338 f
->original_decl_initial
= NULL
;
339 f
->epilogue_delay_list
= NULL
;
342 /* Allocate fixed slots in the stack frame of the current function. */
344 /* Return size needed for stack frame based on slots so far allocated in
346 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
347 the caller may have to do that. */
350 get_func_frame_size (struct function
*f
)
352 if (FRAME_GROWS_DOWNWARD
)
353 return -f
->x_frame_offset
;
355 return f
->x_frame_offset
;
358 /* Return size needed for stack frame based on slots so far allocated.
359 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
360 the caller may have to do that. */
362 get_frame_size (void)
364 return get_func_frame_size (cfun
);
367 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
368 with machine mode MODE.
370 ALIGN controls the amount of alignment for the address of the slot:
371 0 means according to MODE,
372 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
373 -2 means use BITS_PER_UNIT,
374 positive specifies alignment boundary in bits.
376 We do not round to stack_boundary here.
378 FUNCTION specifies the function to allocate in. */
381 assign_stack_local_1 (enum machine_mode mode
, HOST_WIDE_INT size
, int align
,
382 struct function
*function
)
385 int bigend_correction
= 0;
386 unsigned int alignment
;
387 int frame_off
, frame_alignment
, frame_phase
;
394 alignment
= BIGGEST_ALIGNMENT
;
396 alignment
= GET_MODE_ALIGNMENT (mode
);
398 /* Allow the target to (possibly) increase the alignment of this
400 type
= lang_hooks
.types
.type_for_mode (mode
, 0);
402 alignment
= LOCAL_ALIGNMENT (type
, alignment
);
404 alignment
/= BITS_PER_UNIT
;
406 else if (align
== -1)
408 alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
409 size
= CEIL_ROUND (size
, alignment
);
411 else if (align
== -2)
412 alignment
= 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
414 alignment
= align
/ BITS_PER_UNIT
;
416 if (FRAME_GROWS_DOWNWARD
)
417 function
->x_frame_offset
-= size
;
419 /* Ignore alignment we can't do with expected alignment of the boundary. */
420 if (alignment
* BITS_PER_UNIT
> PREFERRED_STACK_BOUNDARY
)
421 alignment
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
423 if (function
->stack_alignment_needed
< alignment
* BITS_PER_UNIT
)
424 function
->stack_alignment_needed
= alignment
* BITS_PER_UNIT
;
426 /* Calculate how many bytes the start of local variables is off from
428 frame_alignment
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
429 frame_off
= STARTING_FRAME_OFFSET
% frame_alignment
;
430 frame_phase
= frame_off
? frame_alignment
- frame_off
: 0;
432 /* Round the frame offset to the specified alignment. The default is
433 to always honor requests to align the stack but a port may choose to
434 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
435 if (STACK_ALIGNMENT_NEEDED
439 /* We must be careful here, since FRAME_OFFSET might be negative and
440 division with a negative dividend isn't as well defined as we might
441 like. So we instead assume that ALIGNMENT is a power of two and
442 use logical operations which are unambiguous. */
443 if (FRAME_GROWS_DOWNWARD
)
444 function
->x_frame_offset
445 = (FLOOR_ROUND (function
->x_frame_offset
- frame_phase
,
446 (unsigned HOST_WIDE_INT
) alignment
)
449 function
->x_frame_offset
450 = (CEIL_ROUND (function
->x_frame_offset
- frame_phase
,
451 (unsigned HOST_WIDE_INT
) alignment
)
455 /* On a big-endian machine, if we are allocating more space than we will use,
456 use the least significant bytes of those that are allocated. */
457 if (BYTES_BIG_ENDIAN
&& mode
!= BLKmode
&& GET_MODE_SIZE (mode
) < size
)
458 bigend_correction
= size
- GET_MODE_SIZE (mode
);
460 /* If we have already instantiated virtual registers, return the actual
461 address relative to the frame pointer. */
462 if (function
== cfun
&& virtuals_instantiated
)
463 addr
= plus_constant (frame_pointer_rtx
,
465 (frame_offset
+ bigend_correction
466 + STARTING_FRAME_OFFSET
, Pmode
));
468 addr
= plus_constant (virtual_stack_vars_rtx
,
470 (function
->x_frame_offset
+ bigend_correction
,
473 if (!FRAME_GROWS_DOWNWARD
)
474 function
->x_frame_offset
+= size
;
476 x
= gen_rtx_MEM (mode
, addr
);
477 MEM_NOTRAP_P (x
) = 1;
479 function
->x_stack_slot_list
480 = gen_rtx_EXPR_LIST (VOIDmode
, x
, function
->x_stack_slot_list
);
482 /* Try to detect frame size overflows on native platforms. */
483 #if BITS_PER_WORD >= 32
484 if ((FRAME_GROWS_DOWNWARD
485 ? (unsigned HOST_WIDE_INT
) -function
->x_frame_offset
486 : (unsigned HOST_WIDE_INT
) function
->x_frame_offset
)
487 > ((unsigned HOST_WIDE_INT
) 1 << (BITS_PER_WORD
- 1))
488 /* Leave room for the fixed part of the frame. */
489 - 64 * UNITS_PER_WORD
)
491 error ("%Jtotal size of local objects too large", function
->decl
);
492 /* Avoid duplicate error messages as much as possible. */
493 function
->x_frame_offset
= 0;
500 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
504 assign_stack_local (enum machine_mode mode
, HOST_WIDE_INT size
, int align
)
506 return assign_stack_local_1 (mode
, size
, align
, cfun
);
510 /* Removes temporary slot TEMP from LIST. */
513 cut_slot_from_list (struct temp_slot
*temp
, struct temp_slot
**list
)
516 temp
->next
->prev
= temp
->prev
;
518 temp
->prev
->next
= temp
->next
;
522 temp
->prev
= temp
->next
= NULL
;
525 /* Inserts temporary slot TEMP to LIST. */
528 insert_slot_to_list (struct temp_slot
*temp
, struct temp_slot
**list
)
532 (*list
)->prev
= temp
;
537 /* Returns the list of used temp slots at LEVEL. */
539 static struct temp_slot
**
540 temp_slots_at_level (int level
)
543 if (!used_temp_slots
)
544 VARRAY_GENERIC_PTR_INIT (used_temp_slots
, 3, "used_temp_slots");
546 while (level
>= (int) VARRAY_ACTIVE_SIZE (used_temp_slots
))
547 VARRAY_PUSH_GENERIC_PTR (used_temp_slots
, NULL
);
549 return (struct temp_slot
**) &VARRAY_GENERIC_PTR (used_temp_slots
, level
);
552 /* Returns the maximal temporary slot level. */
555 max_slot_level (void)
557 if (!used_temp_slots
)
560 return VARRAY_ACTIVE_SIZE (used_temp_slots
) - 1;
563 /* Moves temporary slot TEMP to LEVEL. */
566 move_slot_to_level (struct temp_slot
*temp
, int level
)
568 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
569 insert_slot_to_list (temp
, temp_slots_at_level (level
));
573 /* Make temporary slot TEMP available. */
576 make_slot_available (struct temp_slot
*temp
)
578 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
579 insert_slot_to_list (temp
, &avail_temp_slots
);
584 /* Allocate a temporary stack slot and record it for possible later
587 MODE is the machine mode to be given to the returned rtx.
589 SIZE is the size in units of the space required. We do no rounding here
590 since assign_stack_local will do any required rounding.
592 KEEP is 1 if this slot is to be retained after a call to
593 free_temp_slots. Automatic variables for a block are allocated
594 with this flag. KEEP values of 2 or 3 were needed respectively
595 for variables whose lifetime is controlled by CLEANUP_POINT_EXPRs
596 or for SAVE_EXPRs, but they are now unused.
598 TYPE is the type that will be used for the stack slot. */
601 assign_stack_temp_for_type (enum machine_mode mode
, HOST_WIDE_INT size
,
605 struct temp_slot
*p
, *best_p
= 0, *selected
= NULL
, **pp
;
608 /* If SIZE is -1 it means that somebody tried to allocate a temporary
609 of a variable size. */
610 gcc_assert (size
!= -1);
612 /* These are now unused. */
613 gcc_assert (keep
<= 1);
616 align
= BIGGEST_ALIGNMENT
;
618 align
= GET_MODE_ALIGNMENT (mode
);
621 type
= lang_hooks
.types
.type_for_mode (mode
, 0);
624 align
= LOCAL_ALIGNMENT (type
, align
);
626 /* Try to find an available, already-allocated temporary of the proper
627 mode which meets the size and alignment requirements. Choose the
628 smallest one with the closest alignment. */
629 for (p
= avail_temp_slots
; p
; p
= p
->next
)
631 if (p
->align
>= align
&& p
->size
>= size
&& GET_MODE (p
->slot
) == mode
632 && objects_must_conflict_p (p
->type
, type
)
633 && (best_p
== 0 || best_p
->size
> p
->size
634 || (best_p
->size
== p
->size
&& best_p
->align
> p
->align
)))
636 if (p
->align
== align
&& p
->size
== size
)
639 cut_slot_from_list (selected
, &avail_temp_slots
);
647 /* Make our best, if any, the one to use. */
651 cut_slot_from_list (selected
, &avail_temp_slots
);
653 /* If there are enough aligned bytes left over, make them into a new
654 temp_slot so that the extra bytes don't get wasted. Do this only
655 for BLKmode slots, so that we can be sure of the alignment. */
656 if (GET_MODE (best_p
->slot
) == BLKmode
)
658 int alignment
= best_p
->align
/ BITS_PER_UNIT
;
659 HOST_WIDE_INT rounded_size
= CEIL_ROUND (size
, alignment
);
661 if (best_p
->size
- rounded_size
>= alignment
)
663 p
= ggc_alloc (sizeof (struct temp_slot
));
664 p
->in_use
= p
->addr_taken
= 0;
665 p
->size
= best_p
->size
- rounded_size
;
666 p
->base_offset
= best_p
->base_offset
+ rounded_size
;
667 p
->full_size
= best_p
->full_size
- rounded_size
;
668 p
->slot
= adjust_address_nv (best_p
->slot
, BLKmode
, rounded_size
);
669 p
->align
= best_p
->align
;
671 p
->type
= best_p
->type
;
672 insert_slot_to_list (p
, &avail_temp_slots
);
674 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, p
->slot
,
677 best_p
->size
= rounded_size
;
678 best_p
->full_size
= rounded_size
;
683 /* If we still didn't find one, make a new temporary. */
686 HOST_WIDE_INT frame_offset_old
= frame_offset
;
688 p
= ggc_alloc (sizeof (struct temp_slot
));
690 /* We are passing an explicit alignment request to assign_stack_local.
691 One side effect of that is assign_stack_local will not round SIZE
692 to ensure the frame offset remains suitably aligned.
694 So for requests which depended on the rounding of SIZE, we go ahead
695 and round it now. We also make sure ALIGNMENT is at least
696 BIGGEST_ALIGNMENT. */
697 gcc_assert (mode
!= BLKmode
|| align
== BIGGEST_ALIGNMENT
);
698 p
->slot
= assign_stack_local (mode
,
700 ? CEIL_ROUND (size
, (int) align
/ BITS_PER_UNIT
)
706 /* The following slot size computation is necessary because we don't
707 know the actual size of the temporary slot until assign_stack_local
708 has performed all the frame alignment and size rounding for the
709 requested temporary. Note that extra space added for alignment
710 can be either above or below this stack slot depending on which
711 way the frame grows. We include the extra space if and only if it
712 is above this slot. */
713 if (FRAME_GROWS_DOWNWARD
)
714 p
->size
= frame_offset_old
- frame_offset
;
718 /* Now define the fields used by combine_temp_slots. */
719 if (FRAME_GROWS_DOWNWARD
)
721 p
->base_offset
= frame_offset
;
722 p
->full_size
= frame_offset_old
- frame_offset
;
726 p
->base_offset
= frame_offset_old
;
727 p
->full_size
= frame_offset
- frame_offset_old
;
738 p
->level
= temp_slot_level
;
741 pp
= temp_slots_at_level (p
->level
);
742 insert_slot_to_list (p
, pp
);
744 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
745 slot
= gen_rtx_MEM (mode
, XEXP (p
->slot
, 0));
746 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, slot
, stack_slot_list
);
748 /* If we know the alias set for the memory that will be used, use
749 it. If there's no TYPE, then we don't know anything about the
750 alias set for the memory. */
751 set_mem_alias_set (slot
, type
? get_alias_set (type
) : 0);
752 set_mem_align (slot
, align
);
754 /* If a type is specified, set the relevant flags. */
757 MEM_VOLATILE_P (slot
) = TYPE_VOLATILE (type
);
758 MEM_SET_IN_STRUCT_P (slot
, AGGREGATE_TYPE_P (type
));
760 MEM_NOTRAP_P (slot
) = 1;
765 /* Allocate a temporary stack slot and record it for possible later
766 reuse. First three arguments are same as in preceding function. */
769 assign_stack_temp (enum machine_mode mode
, HOST_WIDE_INT size
, int keep
)
771 return assign_stack_temp_for_type (mode
, size
, keep
, NULL_TREE
);
774 /* Assign a temporary.
775 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
776 and so that should be used in error messages. In either case, we
777 allocate of the given type.
778 KEEP is as for assign_stack_temp.
779 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
780 it is 0 if a register is OK.
781 DONT_PROMOTE is 1 if we should not promote values in register
785 assign_temp (tree type_or_decl
, int keep
, int memory_required
,
786 int dont_promote ATTRIBUTE_UNUSED
)
789 enum machine_mode mode
;
794 if (DECL_P (type_or_decl
))
795 decl
= type_or_decl
, type
= TREE_TYPE (decl
);
797 decl
= NULL
, type
= type_or_decl
;
799 mode
= TYPE_MODE (type
);
801 unsignedp
= TYPE_UNSIGNED (type
);
804 if (mode
== BLKmode
|| memory_required
)
806 HOST_WIDE_INT size
= int_size_in_bytes (type
);
810 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
811 problems with allocating the stack space. */
815 /* Unfortunately, we don't yet know how to allocate variable-sized
816 temporaries. However, sometimes we have a fixed upper limit on
817 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
818 instead. This is the case for Chill variable-sized strings. */
819 if (size
== -1 && TREE_CODE (type
) == ARRAY_TYPE
820 && TYPE_ARRAY_MAX_SIZE (type
) != NULL_TREE
821 && host_integerp (TYPE_ARRAY_MAX_SIZE (type
), 1))
822 size
= tree_low_cst (TYPE_ARRAY_MAX_SIZE (type
), 1);
824 /* If we still haven't been able to get a size, see if the language
825 can compute a maximum size. */
827 && (size_tree
= lang_hooks
.types
.max_size (type
)) != 0
828 && host_integerp (size_tree
, 1))
829 size
= tree_low_cst (size_tree
, 1);
831 /* The size of the temporary may be too large to fit into an integer. */
832 /* ??? Not sure this should happen except for user silliness, so limit
833 this to things that aren't compiler-generated temporaries. The
834 rest of the time we'll die in assign_stack_temp_for_type. */
835 if (decl
&& size
== -1
836 && TREE_CODE (TYPE_SIZE_UNIT (type
)) == INTEGER_CST
)
838 error ("size of variable %q+D is too large", decl
);
842 tmp
= assign_stack_temp_for_type (mode
, size
, keep
, type
);
848 mode
= promote_mode (type
, mode
, &unsignedp
, 0);
851 return gen_reg_rtx (mode
);
854 /* Combine temporary stack slots which are adjacent on the stack.
856 This allows for better use of already allocated stack space. This is only
857 done for BLKmode slots because we can be sure that we won't have alignment
858 problems in this case. */
861 combine_temp_slots (void)
863 struct temp_slot
*p
, *q
, *next
, *next_q
;
866 /* We can't combine slots, because the information about which slot
867 is in which alias set will be lost. */
868 if (flag_strict_aliasing
)
871 /* If there are a lot of temp slots, don't do anything unless
872 high levels of optimization. */
873 if (! flag_expensive_optimizations
)
874 for (p
= avail_temp_slots
, num_slots
= 0; p
; p
= p
->next
, num_slots
++)
875 if (num_slots
> 100 || (num_slots
> 10 && optimize
== 0))
878 for (p
= avail_temp_slots
; p
; p
= next
)
884 if (GET_MODE (p
->slot
) != BLKmode
)
887 for (q
= p
->next
; q
; q
= next_q
)
893 if (GET_MODE (q
->slot
) != BLKmode
)
896 if (p
->base_offset
+ p
->full_size
== q
->base_offset
)
898 /* Q comes after P; combine Q into P. */
900 p
->full_size
+= q
->full_size
;
903 else if (q
->base_offset
+ q
->full_size
== p
->base_offset
)
905 /* P comes after Q; combine P into Q. */
907 q
->full_size
+= p
->full_size
;
912 cut_slot_from_list (q
, &avail_temp_slots
);
915 /* Either delete P or advance past it. */
917 cut_slot_from_list (p
, &avail_temp_slots
);
921 /* Find the temp slot corresponding to the object at address X. */
923 static struct temp_slot
*
924 find_temp_slot_from_address (rtx x
)
930 for (i
= max_slot_level (); i
>= 0; i
--)
931 for (p
= *temp_slots_at_level (i
); p
; p
= p
->next
)
933 if (XEXP (p
->slot
, 0) == x
935 || (GET_CODE (x
) == PLUS
936 && XEXP (x
, 0) == virtual_stack_vars_rtx
937 && GET_CODE (XEXP (x
, 1)) == CONST_INT
938 && INTVAL (XEXP (x
, 1)) >= p
->base_offset
939 && INTVAL (XEXP (x
, 1)) < p
->base_offset
+ p
->full_size
))
942 else if (p
->address
!= 0 && GET_CODE (p
->address
) == EXPR_LIST
)
943 for (next
= p
->address
; next
; next
= XEXP (next
, 1))
944 if (XEXP (next
, 0) == x
)
948 /* If we have a sum involving a register, see if it points to a temp
950 if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 0))
951 && (p
= find_temp_slot_from_address (XEXP (x
, 0))) != 0)
953 else if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 1))
954 && (p
= find_temp_slot_from_address (XEXP (x
, 1))) != 0)
960 /* Indicate that NEW is an alternate way of referring to the temp slot
961 that previously was known by OLD. */
964 update_temp_slot_address (rtx old
, rtx
new)
968 if (rtx_equal_p (old
, new))
971 p
= find_temp_slot_from_address (old
);
973 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
974 is a register, see if one operand of the PLUS is a temporary
975 location. If so, NEW points into it. Otherwise, if both OLD and
976 NEW are a PLUS and if there is a register in common between them.
977 If so, try a recursive call on those values. */
980 if (GET_CODE (old
) != PLUS
)
985 update_temp_slot_address (XEXP (old
, 0), new);
986 update_temp_slot_address (XEXP (old
, 1), new);
989 else if (GET_CODE (new) != PLUS
)
992 if (rtx_equal_p (XEXP (old
, 0), XEXP (new, 0)))
993 update_temp_slot_address (XEXP (old
, 1), XEXP (new, 1));
994 else if (rtx_equal_p (XEXP (old
, 1), XEXP (new, 0)))
995 update_temp_slot_address (XEXP (old
, 0), XEXP (new, 1));
996 else if (rtx_equal_p (XEXP (old
, 0), XEXP (new, 1)))
997 update_temp_slot_address (XEXP (old
, 1), XEXP (new, 0));
998 else if (rtx_equal_p (XEXP (old
, 1), XEXP (new, 1)))
999 update_temp_slot_address (XEXP (old
, 0), XEXP (new, 0));
1004 /* Otherwise add an alias for the temp's address. */
1005 else if (p
->address
== 0)
1009 if (GET_CODE (p
->address
) != EXPR_LIST
)
1010 p
->address
= gen_rtx_EXPR_LIST (VOIDmode
, p
->address
, NULL_RTX
);
1012 p
->address
= gen_rtx_EXPR_LIST (VOIDmode
, new, p
->address
);
1016 /* If X could be a reference to a temporary slot, mark the fact that its
1017 address was taken. */
1020 mark_temp_addr_taken (rtx x
)
1022 struct temp_slot
*p
;
1027 /* If X is not in memory or is at a constant address, it cannot be in
1028 a temporary slot. */
1029 if (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0)))
1032 p
= find_temp_slot_from_address (XEXP (x
, 0));
1037 /* If X could be a reference to a temporary slot, mark that slot as
1038 belonging to the to one level higher than the current level. If X
1039 matched one of our slots, just mark that one. Otherwise, we can't
1040 easily predict which it is, so upgrade all of them. Kept slots
1041 need not be touched.
1043 This is called when an ({...}) construct occurs and a statement
1044 returns a value in memory. */
1047 preserve_temp_slots (rtx x
)
1049 struct temp_slot
*p
= 0, *next
;
1051 /* If there is no result, we still might have some objects whose address
1052 were taken, so we need to make sure they stay around. */
1055 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1060 move_slot_to_level (p
, temp_slot_level
- 1);
1066 /* If X is a register that is being used as a pointer, see if we have
1067 a temporary slot we know it points to. To be consistent with
1068 the code below, we really should preserve all non-kept slots
1069 if we can't find a match, but that seems to be much too costly. */
1070 if (REG_P (x
) && REG_POINTER (x
))
1071 p
= find_temp_slot_from_address (x
);
1073 /* If X is not in memory or is at a constant address, it cannot be in
1074 a temporary slot, but it can contain something whose address was
1076 if (p
== 0 && (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0))))
1078 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1083 move_slot_to_level (p
, temp_slot_level
- 1);
1089 /* First see if we can find a match. */
1091 p
= find_temp_slot_from_address (XEXP (x
, 0));
1095 /* Move everything at our level whose address was taken to our new
1096 level in case we used its address. */
1097 struct temp_slot
*q
;
1099 if (p
->level
== temp_slot_level
)
1101 for (q
= *temp_slots_at_level (temp_slot_level
); q
; q
= next
)
1105 if (p
!= q
&& q
->addr_taken
)
1106 move_slot_to_level (q
, temp_slot_level
- 1);
1109 move_slot_to_level (p
, temp_slot_level
- 1);
1115 /* Otherwise, preserve all non-kept slots at this level. */
1116 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1121 move_slot_to_level (p
, temp_slot_level
- 1);
1125 /* Free all temporaries used so far. This is normally called at the
1126 end of generating code for a statement. */
1129 free_temp_slots (void)
1131 struct temp_slot
*p
, *next
;
1133 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1138 make_slot_available (p
);
1141 combine_temp_slots ();
1144 /* Push deeper into the nesting level for stack temporaries. */
1147 push_temp_slots (void)
1152 /* Pop a temporary nesting level. All slots in use in the current level
1156 pop_temp_slots (void)
1158 struct temp_slot
*p
, *next
;
1160 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1163 make_slot_available (p
);
1166 combine_temp_slots ();
1171 /* Initialize temporary slots. */
1174 init_temp_slots (void)
1176 /* We have not allocated any temporaries yet. */
1177 avail_temp_slots
= 0;
1178 used_temp_slots
= 0;
1179 temp_slot_level
= 0;
1182 /* These routines are responsible for converting virtual register references
1183 to the actual hard register references once RTL generation is complete.
1185 The following four variables are used for communication between the
1186 routines. They contain the offsets of the virtual registers from their
1187 respective hard registers. */
1189 static int in_arg_offset
;
1190 static int var_offset
;
1191 static int dynamic_offset
;
1192 static int out_arg_offset
;
1193 static int cfa_offset
;
1195 /* In most machines, the stack pointer register is equivalent to the bottom
1198 #ifndef STACK_POINTER_OFFSET
1199 #define STACK_POINTER_OFFSET 0
1202 /* If not defined, pick an appropriate default for the offset of dynamically
1203 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1204 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1206 #ifndef STACK_DYNAMIC_OFFSET
1208 /* The bottom of the stack points to the actual arguments. If
1209 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1210 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1211 stack space for register parameters is not pushed by the caller, but
1212 rather part of the fixed stack areas and hence not included in
1213 `current_function_outgoing_args_size'. Nevertheless, we must allow
1214 for it when allocating stack dynamic objects. */
1216 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
1217 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1218 ((ACCUMULATE_OUTGOING_ARGS \
1219 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
1220 + (STACK_POINTER_OFFSET)) \
1223 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1224 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
1225 + (STACK_POINTER_OFFSET))
1230 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1231 is a virtual register, return the equivalent hard register and set the
1232 offset indirectly through the pointer. Otherwise, return 0. */
1235 instantiate_new_reg (rtx x
, HOST_WIDE_INT
*poffset
)
1238 HOST_WIDE_INT offset
;
1240 if (x
== virtual_incoming_args_rtx
)
1241 new = arg_pointer_rtx
, offset
= in_arg_offset
;
1242 else if (x
== virtual_stack_vars_rtx
)
1243 new = frame_pointer_rtx
, offset
= var_offset
;
1244 else if (x
== virtual_stack_dynamic_rtx
)
1245 new = stack_pointer_rtx
, offset
= dynamic_offset
;
1246 else if (x
== virtual_outgoing_args_rtx
)
1247 new = stack_pointer_rtx
, offset
= out_arg_offset
;
1248 else if (x
== virtual_cfa_rtx
)
1250 #ifdef FRAME_POINTER_CFA_OFFSET
1251 new = frame_pointer_rtx
;
1253 new = arg_pointer_rtx
;
1255 offset
= cfa_offset
;
1264 /* A subroutine of instantiate_virtual_regs, called via for_each_rtx.
1265 Instantiate any virtual registers present inside of *LOC. The expression
1266 is simplified, as much as possible, but is not to be considered "valid"
1267 in any sense implied by the target. If any change is made, set CHANGED
1271 instantiate_virtual_regs_in_rtx (rtx
*loc
, void *data
)
1273 HOST_WIDE_INT offset
;
1274 bool *changed
= (bool *) data
;
1281 switch (GET_CODE (x
))
1284 new = instantiate_new_reg (x
, &offset
);
1287 *loc
= plus_constant (new, offset
);
1294 new = instantiate_new_reg (XEXP (x
, 0), &offset
);
1297 new = plus_constant (new, offset
);
1298 *loc
= simplify_gen_binary (PLUS
, GET_MODE (x
), new, XEXP (x
, 1));
1304 /* FIXME -- from old code */
1305 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1306 we can commute the PLUS and SUBREG because pointers into the
1307 frame are well-behaved. */
1317 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1318 matches the predicate for insn CODE operand OPERAND. */
1321 safe_insn_predicate (int code
, int operand
, rtx x
)
1323 const struct insn_operand_data
*op_data
;
1328 op_data
= &insn_data
[code
].operand
[operand
];
1329 if (op_data
->predicate
== NULL
)
1332 return op_data
->predicate (x
, op_data
->mode
);
1335 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1336 registers present inside of insn. The result will be a valid insn. */
1339 instantiate_virtual_regs_in_insn (rtx insn
)
1341 HOST_WIDE_INT offset
;
1343 bool any_change
= false;
1344 rtx set
, new, x
, seq
;
1346 /* There are some special cases to be handled first. */
1347 set
= single_set (insn
);
1350 /* We're allowed to assign to a virtual register. This is interpreted
1351 to mean that the underlying register gets assigned the inverse
1352 transformation. This is used, for example, in the handling of
1354 new = instantiate_new_reg (SET_DEST (set
), &offset
);
1359 for_each_rtx (&SET_SRC (set
), instantiate_virtual_regs_in_rtx
, NULL
);
1360 x
= simplify_gen_binary (PLUS
, GET_MODE (new), SET_SRC (set
),
1362 x
= force_operand (x
, new);
1364 emit_move_insn (new, x
);
1369 emit_insn_before (seq
, insn
);
1374 /* Handle a straight copy from a virtual register by generating a
1375 new add insn. The difference between this and falling through
1376 to the generic case is avoiding a new pseudo and eliminating a
1377 move insn in the initial rtl stream. */
1378 new = instantiate_new_reg (SET_SRC (set
), &offset
);
1379 if (new && offset
!= 0
1380 && REG_P (SET_DEST (set
))
1381 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1385 x
= expand_simple_binop (GET_MODE (SET_DEST (set
)), PLUS
,
1386 new, GEN_INT (offset
), SET_DEST (set
),
1387 1, OPTAB_LIB_WIDEN
);
1388 if (x
!= SET_DEST (set
))
1389 emit_move_insn (SET_DEST (set
), x
);
1394 emit_insn_before (seq
, insn
);
1399 extract_insn (insn
);
1400 insn_code
= INSN_CODE (insn
);
1402 /* Handle a plus involving a virtual register by determining if the
1403 operands remain valid if they're modified in place. */
1404 if (GET_CODE (SET_SRC (set
)) == PLUS
1405 && recog_data
.n_operands
>= 3
1406 && recog_data
.operand_loc
[1] == &XEXP (SET_SRC (set
), 0)
1407 && recog_data
.operand_loc
[2] == &XEXP (SET_SRC (set
), 1)
1408 && GET_CODE (recog_data
.operand
[2]) == CONST_INT
1409 && (new = instantiate_new_reg (recog_data
.operand
[1], &offset
)))
1411 offset
+= INTVAL (recog_data
.operand
[2]);
1413 /* If the sum is zero, then replace with a plain move. */
1415 && REG_P (SET_DEST (set
))
1416 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1419 emit_move_insn (SET_DEST (set
), new);
1423 emit_insn_before (seq
, insn
);
1428 x
= gen_int_mode (offset
, recog_data
.operand_mode
[2]);
1430 /* Using validate_change and apply_change_group here leaves
1431 recog_data in an invalid state. Since we know exactly what
1432 we want to check, do those two by hand. */
1433 if (safe_insn_predicate (insn_code
, 1, new)
1434 && safe_insn_predicate (insn_code
, 2, x
))
1436 *recog_data
.operand_loc
[1] = recog_data
.operand
[1] = new;
1437 *recog_data
.operand_loc
[2] = recog_data
.operand
[2] = x
;
1440 /* Fall through into the regular operand fixup loop in
1441 order to take care of operands other than 1 and 2. */
1447 extract_insn (insn
);
1448 insn_code
= INSN_CODE (insn
);
1451 /* In the general case, we expect virtual registers to appear only in
1452 operands, and then only as either bare registers or inside memories. */
1453 for (i
= 0; i
< recog_data
.n_operands
; ++i
)
1455 x
= recog_data
.operand
[i
];
1456 switch (GET_CODE (x
))
1460 rtx addr
= XEXP (x
, 0);
1461 bool changed
= false;
1463 for_each_rtx (&addr
, instantiate_virtual_regs_in_rtx
, &changed
);
1468 x
= replace_equiv_address (x
, addr
);
1472 emit_insn_before (seq
, insn
);
1477 new = instantiate_new_reg (x
, &offset
);
1486 /* Careful, special mode predicates may have stuff in
1487 insn_data[insn_code].operand[i].mode that isn't useful
1488 to us for computing a new value. */
1489 /* ??? Recognize address_operand and/or "p" constraints
1490 to see if (plus new offset) is a valid before we put
1491 this through expand_simple_binop. */
1492 x
= expand_simple_binop (GET_MODE (x
), PLUS
, new,
1493 GEN_INT (offset
), NULL_RTX
,
1494 1, OPTAB_LIB_WIDEN
);
1497 emit_insn_before (seq
, insn
);
1502 new = instantiate_new_reg (SUBREG_REG (x
), &offset
);
1508 new = expand_simple_binop (GET_MODE (new), PLUS
, new,
1509 GEN_INT (offset
), NULL_RTX
,
1510 1, OPTAB_LIB_WIDEN
);
1513 emit_insn_before (seq
, insn
);
1515 x
= simplify_gen_subreg (recog_data
.operand_mode
[i
], new,
1516 GET_MODE (new), SUBREG_BYTE (x
));
1523 /* At this point, X contains the new value for the operand.
1524 Validate the new value vs the insn predicate. Note that
1525 asm insns will have insn_code -1 here. */
1526 if (!safe_insn_predicate (insn_code
, i
, x
))
1529 x
= force_reg (insn_data
[insn_code
].operand
[i
].mode
, x
);
1533 emit_insn_before (seq
, insn
);
1536 *recog_data
.operand_loc
[i
] = recog_data
.operand
[i
] = x
;
1542 /* Propagate operand changes into the duplicates. */
1543 for (i
= 0; i
< recog_data
.n_dups
; ++i
)
1544 *recog_data
.dup_loc
[i
]
1545 = recog_data
.operand
[(unsigned)recog_data
.dup_num
[i
]];
1547 /* Force re-recognition of the instruction for validation. */
1548 INSN_CODE (insn
) = -1;
1551 if (asm_noperands (PATTERN (insn
)) >= 0)
1553 if (!check_asm_operands (PATTERN (insn
)))
1555 error_for_asm (insn
, "impossible constraint in %<asm%>");
1561 if (recog_memoized (insn
) < 0)
1562 fatal_insn_not_found (insn
);
1566 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1567 do any instantiation required. */
1570 instantiate_decl (rtx x
)
1577 /* If this is a CONCAT, recurse for the pieces. */
1578 if (GET_CODE (x
) == CONCAT
)
1580 instantiate_decl (XEXP (x
, 0));
1581 instantiate_decl (XEXP (x
, 1));
1585 /* If this is not a MEM, no need to do anything. Similarly if the
1586 address is a constant or a register that is not a virtual register. */
1591 if (CONSTANT_P (addr
)
1593 && (REGNO (addr
) < FIRST_VIRTUAL_REGISTER
1594 || REGNO (addr
) > LAST_VIRTUAL_REGISTER
)))
1597 for_each_rtx (&XEXP (x
, 0), instantiate_virtual_regs_in_rtx
, NULL
);
1600 /* Helper for instantiate_decls called via walk_tree: Process all decls
1601 in the given DECL_VALUE_EXPR. */
1604 instantiate_expr (tree
*tp
, int *walk_subtrees
, void *data ATTRIBUTE_UNUSED
)
1610 if (DECL_P (t
) && DECL_RTL_SET_P (t
))
1611 instantiate_decl (DECL_RTL (t
));
1616 /* Subroutine of instantiate_decls: Process all decls in the given
1617 BLOCK node and all its subblocks. */
1620 instantiate_decls_1 (tree let
)
1624 for (t
= BLOCK_VARS (let
); t
; t
= TREE_CHAIN (t
))
1626 if (DECL_RTL_SET_P (t
))
1627 instantiate_decl (DECL_RTL (t
));
1628 if (TREE_CODE (t
) == VAR_DECL
&& DECL_HAS_VALUE_EXPR_P (t
))
1630 tree v
= DECL_VALUE_EXPR (t
);
1631 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1635 /* Process all subblocks. */
1636 for (t
= BLOCK_SUBBLOCKS (let
); t
; t
= TREE_CHAIN (t
))
1637 instantiate_decls_1 (t
);
1640 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1641 all virtual registers in their DECL_RTL's. */
1644 instantiate_decls (tree fndecl
)
1648 /* Process all parameters of the function. */
1649 for (decl
= DECL_ARGUMENTS (fndecl
); decl
; decl
= TREE_CHAIN (decl
))
1651 instantiate_decl (DECL_RTL (decl
));
1652 instantiate_decl (DECL_INCOMING_RTL (decl
));
1653 if (DECL_HAS_VALUE_EXPR_P (decl
))
1655 tree v
= DECL_VALUE_EXPR (decl
);
1656 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1660 /* Now process all variables defined in the function or its subblocks. */
1661 instantiate_decls_1 (DECL_INITIAL (fndecl
));
1664 /* Pass through the INSNS of function FNDECL and convert virtual register
1665 references to hard register references. */
1668 instantiate_virtual_regs (void)
1672 /* Compute the offsets to use for this function. */
1673 in_arg_offset
= FIRST_PARM_OFFSET (current_function_decl
);
1674 var_offset
= STARTING_FRAME_OFFSET
;
1675 dynamic_offset
= STACK_DYNAMIC_OFFSET (current_function_decl
);
1676 out_arg_offset
= STACK_POINTER_OFFSET
;
1677 #ifdef FRAME_POINTER_CFA_OFFSET
1678 cfa_offset
= FRAME_POINTER_CFA_OFFSET (current_function_decl
);
1680 cfa_offset
= ARG_POINTER_CFA_OFFSET (current_function_decl
);
1683 /* Initialize recognition, indicating that volatile is OK. */
1686 /* Scan through all the insns, instantiating every virtual register still
1688 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
1691 /* These patterns in the instruction stream can never be recognized.
1692 Fortunately, they shouldn't contain virtual registers either. */
1693 if (GET_CODE (PATTERN (insn
)) == USE
1694 || GET_CODE (PATTERN (insn
)) == CLOBBER
1695 || GET_CODE (PATTERN (insn
)) == ADDR_VEC
1696 || GET_CODE (PATTERN (insn
)) == ADDR_DIFF_VEC
1697 || GET_CODE (PATTERN (insn
)) == ASM_INPUT
)
1700 instantiate_virtual_regs_in_insn (insn
);
1702 if (INSN_DELETED_P (insn
))
1705 for_each_rtx (®_NOTES (insn
), instantiate_virtual_regs_in_rtx
, NULL
);
1707 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1708 if (GET_CODE (insn
) == CALL_INSN
)
1709 for_each_rtx (&CALL_INSN_FUNCTION_USAGE (insn
),
1710 instantiate_virtual_regs_in_rtx
, NULL
);
1713 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1714 instantiate_decls (current_function_decl
);
1716 /* Indicate that, from now on, assign_stack_local should use
1717 frame_pointer_rtx. */
1718 virtuals_instantiated
= 1;
1721 struct tree_opt_pass pass_instantiate_virtual_regs
=
1725 instantiate_virtual_regs
, /* execute */
1728 0, /* static_pass_number */
1730 0, /* properties_required */
1731 0, /* properties_provided */
1732 0, /* properties_destroyed */
1733 0, /* todo_flags_start */
1734 TODO_dump_func
, /* todo_flags_finish */
1739 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
1740 This means a type for which function calls must pass an address to the
1741 function or get an address back from the function.
1742 EXP may be a type node or an expression (whose type is tested). */
1745 aggregate_value_p (tree exp
, tree fntype
)
1747 int i
, regno
, nregs
;
1750 tree type
= (TYPE_P (exp
)) ? exp
: TREE_TYPE (exp
);
1753 switch (TREE_CODE (fntype
))
1756 fntype
= get_callee_fndecl (fntype
);
1757 fntype
= fntype
? TREE_TYPE (fntype
) : 0;
1760 fntype
= TREE_TYPE (fntype
);
1765 case IDENTIFIER_NODE
:
1769 /* We don't expect other rtl types here. */
1773 if (TREE_CODE (type
) == VOID_TYPE
)
1775 /* If the front end has decided that this needs to be passed by
1776 reference, do so. */
1777 if ((TREE_CODE (exp
) == PARM_DECL
|| TREE_CODE (exp
) == RESULT_DECL
)
1778 && DECL_BY_REFERENCE (exp
))
1780 if (targetm
.calls
.return_in_memory (type
, fntype
))
1782 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
1783 and thus can't be returned in registers. */
1784 if (TREE_ADDRESSABLE (type
))
1786 if (flag_pcc_struct_return
&& AGGREGATE_TYPE_P (type
))
1788 /* Make sure we have suitable call-clobbered regs to return
1789 the value in; if not, we must return it in memory. */
1790 reg
= hard_function_value (type
, 0, fntype
, 0);
1792 /* If we have something other than a REG (e.g. a PARALLEL), then assume
1797 regno
= REGNO (reg
);
1798 nregs
= hard_regno_nregs
[regno
][TYPE_MODE (type
)];
1799 for (i
= 0; i
< nregs
; i
++)
1800 if (! call_used_regs
[regno
+ i
])
1805 /* Return true if we should assign DECL a pseudo register; false if it
1806 should live on the local stack. */
1809 use_register_for_decl (tree decl
)
1811 /* Honor volatile. */
1812 if (TREE_SIDE_EFFECTS (decl
))
1815 /* Honor addressability. */
1816 if (TREE_ADDRESSABLE (decl
))
1819 /* Only register-like things go in registers. */
1820 if (DECL_MODE (decl
) == BLKmode
)
1823 /* If -ffloat-store specified, don't put explicit float variables
1825 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
1826 propagates values across these stores, and it probably shouldn't. */
1827 if (flag_float_store
&& FLOAT_TYPE_P (TREE_TYPE (decl
)))
1830 /* If we're not interested in tracking debugging information for
1831 this decl, then we can certainly put it in a register. */
1832 if (DECL_IGNORED_P (decl
))
1835 return (optimize
|| DECL_REGISTER (decl
));
1838 /* Return true if TYPE should be passed by invisible reference. */
1841 pass_by_reference (CUMULATIVE_ARGS
*ca
, enum machine_mode mode
,
1842 tree type
, bool named_arg
)
1846 /* If this type contains non-trivial constructors, then it is
1847 forbidden for the middle-end to create any new copies. */
1848 if (TREE_ADDRESSABLE (type
))
1851 /* GCC post 3.4 passes *all* variable sized types by reference. */
1852 if (!TYPE_SIZE (type
) || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
1856 return targetm
.calls
.pass_by_reference (ca
, mode
, type
, named_arg
);
1859 /* Return true if TYPE, which is passed by reference, should be callee
1860 copied instead of caller copied. */
1863 reference_callee_copied (CUMULATIVE_ARGS
*ca
, enum machine_mode mode
,
1864 tree type
, bool named_arg
)
1866 if (type
&& TREE_ADDRESSABLE (type
))
1868 return targetm
.calls
.callee_copies (ca
, mode
, type
, named_arg
);
1871 /* Structures to communicate between the subroutines of assign_parms.
1872 The first holds data persistent across all parameters, the second
1873 is cleared out for each parameter. */
1875 struct assign_parm_data_all
1877 CUMULATIVE_ARGS args_so_far
;
1878 struct args_size stack_args_size
;
1879 tree function_result_decl
;
1881 rtx conversion_insns
;
1882 HOST_WIDE_INT pretend_args_size
;
1883 HOST_WIDE_INT extra_pretend_bytes
;
1884 int reg_parm_stack_space
;
1887 struct assign_parm_data_one
1893 enum machine_mode nominal_mode
;
1894 enum machine_mode passed_mode
;
1895 enum machine_mode promoted_mode
;
1896 struct locate_and_pad_arg_data locate
;
1898 BOOL_BITFIELD named_arg
: 1;
1899 BOOL_BITFIELD passed_pointer
: 1;
1900 BOOL_BITFIELD on_stack
: 1;
1901 BOOL_BITFIELD loaded_in_reg
: 1;
1904 /* A subroutine of assign_parms. Initialize ALL. */
1907 assign_parms_initialize_all (struct assign_parm_data_all
*all
)
1911 memset (all
, 0, sizeof (*all
));
1913 fntype
= TREE_TYPE (current_function_decl
);
1915 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
1916 INIT_CUMULATIVE_INCOMING_ARGS (all
->args_so_far
, fntype
, NULL_RTX
);
1918 INIT_CUMULATIVE_ARGS (all
->args_so_far
, fntype
, NULL_RTX
,
1919 current_function_decl
, -1);
1922 #ifdef REG_PARM_STACK_SPACE
1923 all
->reg_parm_stack_space
= REG_PARM_STACK_SPACE (current_function_decl
);
1927 /* If ARGS contains entries with complex types, split the entry into two
1928 entries of the component type. Return a new list of substitutions are
1929 needed, else the old list. */
1932 split_complex_args (tree args
)
1936 /* Before allocating memory, check for the common case of no complex. */
1937 for (p
= args
; p
; p
= TREE_CHAIN (p
))
1939 tree type
= TREE_TYPE (p
);
1940 if (TREE_CODE (type
) == COMPLEX_TYPE
1941 && targetm
.calls
.split_complex_arg (type
))
1947 args
= copy_list (args
);
1949 for (p
= args
; p
; p
= TREE_CHAIN (p
))
1951 tree type
= TREE_TYPE (p
);
1952 if (TREE_CODE (type
) == COMPLEX_TYPE
1953 && targetm
.calls
.split_complex_arg (type
))
1956 tree subtype
= TREE_TYPE (type
);
1957 bool addressable
= TREE_ADDRESSABLE (p
);
1959 /* Rewrite the PARM_DECL's type with its component. */
1960 TREE_TYPE (p
) = subtype
;
1961 DECL_ARG_TYPE (p
) = TREE_TYPE (DECL_ARG_TYPE (p
));
1962 DECL_MODE (p
) = VOIDmode
;
1963 DECL_SIZE (p
) = NULL
;
1964 DECL_SIZE_UNIT (p
) = NULL
;
1965 /* If this arg must go in memory, put it in a pseudo here.
1966 We can't allow it to go in memory as per normal parms,
1967 because the usual place might not have the imag part
1968 adjacent to the real part. */
1969 DECL_ARTIFICIAL (p
) = addressable
;
1970 DECL_IGNORED_P (p
) = addressable
;
1971 TREE_ADDRESSABLE (p
) = 0;
1974 /* Build a second synthetic decl. */
1975 decl
= build_decl (PARM_DECL
, NULL_TREE
, subtype
);
1976 DECL_ARG_TYPE (decl
) = DECL_ARG_TYPE (p
);
1977 DECL_ARTIFICIAL (decl
) = addressable
;
1978 DECL_IGNORED_P (decl
) = addressable
;
1979 layout_decl (decl
, 0);
1981 /* Splice it in; skip the new decl. */
1982 TREE_CHAIN (decl
) = TREE_CHAIN (p
);
1983 TREE_CHAIN (p
) = decl
;
1991 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
1992 the hidden struct return argument, and (abi willing) complex args.
1993 Return the new parameter list. */
1996 assign_parms_augmented_arg_list (struct assign_parm_data_all
*all
)
1998 tree fndecl
= current_function_decl
;
1999 tree fntype
= TREE_TYPE (fndecl
);
2000 tree fnargs
= DECL_ARGUMENTS (fndecl
);
2002 /* If struct value address is treated as the first argument, make it so. */
2003 if (aggregate_value_p (DECL_RESULT (fndecl
), fndecl
)
2004 && ! current_function_returns_pcc_struct
2005 && targetm
.calls
.struct_value_rtx (TREE_TYPE (fndecl
), 1) == 0)
2007 tree type
= build_pointer_type (TREE_TYPE (fntype
));
2010 decl
= build_decl (PARM_DECL
, NULL_TREE
, type
);
2011 DECL_ARG_TYPE (decl
) = type
;
2012 DECL_ARTIFICIAL (decl
) = 1;
2013 DECL_IGNORED_P (decl
) = 1;
2015 TREE_CHAIN (decl
) = fnargs
;
2017 all
->function_result_decl
= decl
;
2020 all
->orig_fnargs
= fnargs
;
2022 /* If the target wants to split complex arguments into scalars, do so. */
2023 if (targetm
.calls
.split_complex_arg
)
2024 fnargs
= split_complex_args (fnargs
);
2029 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2030 data for the parameter. Incorporate ABI specifics such as pass-by-
2031 reference and type promotion. */
2034 assign_parm_find_data_types (struct assign_parm_data_all
*all
, tree parm
,
2035 struct assign_parm_data_one
*data
)
2037 tree nominal_type
, passed_type
;
2038 enum machine_mode nominal_mode
, passed_mode
, promoted_mode
;
2040 memset (data
, 0, sizeof (*data
));
2042 /* NAMED_ARG is a mis-nomer. We really mean 'non-varadic'. */
2043 if (!current_function_stdarg
)
2044 data
->named_arg
= 1; /* No varadic parms. */
2045 else if (TREE_CHAIN (parm
))
2046 data
->named_arg
= 1; /* Not the last non-varadic parm. */
2047 else if (targetm
.calls
.strict_argument_naming (&all
->args_so_far
))
2048 data
->named_arg
= 1; /* Only varadic ones are unnamed. */
2050 data
->named_arg
= 0; /* Treat as varadic. */
2052 nominal_type
= TREE_TYPE (parm
);
2053 passed_type
= DECL_ARG_TYPE (parm
);
2055 /* Look out for errors propagating this far. Also, if the parameter's
2056 type is void then its value doesn't matter. */
2057 if (TREE_TYPE (parm
) == error_mark_node
2058 /* This can happen after weird syntax errors
2059 or if an enum type is defined among the parms. */
2060 || TREE_CODE (parm
) != PARM_DECL
2061 || passed_type
== NULL
2062 || VOID_TYPE_P (nominal_type
))
2064 nominal_type
= passed_type
= void_type_node
;
2065 nominal_mode
= passed_mode
= promoted_mode
= VOIDmode
;
2069 /* Find mode of arg as it is passed, and mode of arg as it should be
2070 during execution of this function. */
2071 passed_mode
= TYPE_MODE (passed_type
);
2072 nominal_mode
= TYPE_MODE (nominal_type
);
2074 /* If the parm is to be passed as a transparent union, use the type of
2075 the first field for the tests below. We have already verified that
2076 the modes are the same. */
2077 if (TREE_CODE (passed_type
) == UNION_TYPE
2078 && TYPE_TRANSPARENT_UNION (passed_type
))
2079 passed_type
= TREE_TYPE (TYPE_FIELDS (passed_type
));
2081 /* See if this arg was passed by invisible reference. */
2082 if (pass_by_reference (&all
->args_so_far
, passed_mode
,
2083 passed_type
, data
->named_arg
))
2085 passed_type
= nominal_type
= build_pointer_type (passed_type
);
2086 data
->passed_pointer
= true;
2087 passed_mode
= nominal_mode
= Pmode
;
2090 /* Find mode as it is passed by the ABI. */
2091 promoted_mode
= passed_mode
;
2092 if (targetm
.calls
.promote_function_args (TREE_TYPE (current_function_decl
)))
2094 int unsignedp
= TYPE_UNSIGNED (passed_type
);
2095 promoted_mode
= promote_mode (passed_type
, promoted_mode
,
2100 data
->nominal_type
= nominal_type
;
2101 data
->passed_type
= passed_type
;
2102 data
->nominal_mode
= nominal_mode
;
2103 data
->passed_mode
= passed_mode
;
2104 data
->promoted_mode
= promoted_mode
;
2107 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2110 assign_parms_setup_varargs (struct assign_parm_data_all
*all
,
2111 struct assign_parm_data_one
*data
, bool no_rtl
)
2113 int varargs_pretend_bytes
= 0;
2115 targetm
.calls
.setup_incoming_varargs (&all
->args_so_far
,
2116 data
->promoted_mode
,
2118 &varargs_pretend_bytes
, no_rtl
);
2120 /* If the back-end has requested extra stack space, record how much is
2121 needed. Do not change pretend_args_size otherwise since it may be
2122 nonzero from an earlier partial argument. */
2123 if (varargs_pretend_bytes
> 0)
2124 all
->pretend_args_size
= varargs_pretend_bytes
;
2127 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2128 the incoming location of the current parameter. */
2131 assign_parm_find_entry_rtl (struct assign_parm_data_all
*all
,
2132 struct assign_parm_data_one
*data
)
2134 HOST_WIDE_INT pretend_bytes
= 0;
2138 if (data
->promoted_mode
== VOIDmode
)
2140 data
->entry_parm
= data
->stack_parm
= const0_rtx
;
2144 #ifdef FUNCTION_INCOMING_ARG
2145 entry_parm
= FUNCTION_INCOMING_ARG (all
->args_so_far
, data
->promoted_mode
,
2146 data
->passed_type
, data
->named_arg
);
2148 entry_parm
= FUNCTION_ARG (all
->args_so_far
, data
->promoted_mode
,
2149 data
->passed_type
, data
->named_arg
);
2152 if (entry_parm
== 0)
2153 data
->promoted_mode
= data
->passed_mode
;
2155 /* Determine parm's home in the stack, in case it arrives in the stack
2156 or we should pretend it did. Compute the stack position and rtx where
2157 the argument arrives and its size.
2159 There is one complexity here: If this was a parameter that would
2160 have been passed in registers, but wasn't only because it is
2161 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2162 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2163 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2164 as it was the previous time. */
2165 in_regs
= entry_parm
!= 0;
2166 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2169 if (!in_regs
&& !data
->named_arg
)
2171 if (targetm
.calls
.pretend_outgoing_varargs_named (&all
->args_so_far
))
2174 #ifdef FUNCTION_INCOMING_ARG
2175 tem
= FUNCTION_INCOMING_ARG (all
->args_so_far
, data
->promoted_mode
,
2176 data
->passed_type
, true);
2178 tem
= FUNCTION_ARG (all
->args_so_far
, data
->promoted_mode
,
2179 data
->passed_type
, true);
2181 in_regs
= tem
!= NULL
;
2185 /* If this parameter was passed both in registers and in the stack, use
2186 the copy on the stack. */
2187 if (targetm
.calls
.must_pass_in_stack (data
->promoted_mode
,
2195 partial
= targetm
.calls
.arg_partial_bytes (&all
->args_so_far
,
2196 data
->promoted_mode
,
2199 data
->partial
= partial
;
2201 /* The caller might already have allocated stack space for the
2202 register parameters. */
2203 if (partial
!= 0 && all
->reg_parm_stack_space
== 0)
2205 /* Part of this argument is passed in registers and part
2206 is passed on the stack. Ask the prologue code to extend
2207 the stack part so that we can recreate the full value.
2209 PRETEND_BYTES is the size of the registers we need to store.
2210 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2211 stack space that the prologue should allocate.
2213 Internally, gcc assumes that the argument pointer is aligned
2214 to STACK_BOUNDARY bits. This is used both for alignment
2215 optimizations (see init_emit) and to locate arguments that are
2216 aligned to more than PARM_BOUNDARY bits. We must preserve this
2217 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2218 a stack boundary. */
2220 /* We assume at most one partial arg, and it must be the first
2221 argument on the stack. */
2222 gcc_assert (!all
->extra_pretend_bytes
&& !all
->pretend_args_size
);
2224 pretend_bytes
= partial
;
2225 all
->pretend_args_size
= CEIL_ROUND (pretend_bytes
, STACK_BYTES
);
2227 /* We want to align relative to the actual stack pointer, so
2228 don't include this in the stack size until later. */
2229 all
->extra_pretend_bytes
= all
->pretend_args_size
;
2233 locate_and_pad_parm (data
->promoted_mode
, data
->passed_type
, in_regs
,
2234 entry_parm
? data
->partial
: 0, current_function_decl
,
2235 &all
->stack_args_size
, &data
->locate
);
2237 /* Adjust offsets to include the pretend args. */
2238 pretend_bytes
= all
->extra_pretend_bytes
- pretend_bytes
;
2239 data
->locate
.slot_offset
.constant
+= pretend_bytes
;
2240 data
->locate
.offset
.constant
+= pretend_bytes
;
2242 data
->entry_parm
= entry_parm
;
2245 /* A subroutine of assign_parms. If there is actually space on the stack
2246 for this parm, count it in stack_args_size and return true. */
2249 assign_parm_is_stack_parm (struct assign_parm_data_all
*all
,
2250 struct assign_parm_data_one
*data
)
2252 /* Trivially true if we've no incoming register. */
2253 if (data
->entry_parm
== NULL
)
2255 /* Also true if we're partially in registers and partially not,
2256 since we've arranged to drop the entire argument on the stack. */
2257 else if (data
->partial
!= 0)
2259 /* Also true if the target says that it's passed in both registers
2260 and on the stack. */
2261 else if (GET_CODE (data
->entry_parm
) == PARALLEL
2262 && XEXP (XVECEXP (data
->entry_parm
, 0, 0), 0) == NULL_RTX
)
2264 /* Also true if the target says that there's stack allocated for
2265 all register parameters. */
2266 else if (all
->reg_parm_stack_space
> 0)
2268 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2272 all
->stack_args_size
.constant
+= data
->locate
.size
.constant
;
2273 if (data
->locate
.size
.var
)
2274 ADD_PARM_SIZE (all
->stack_args_size
, data
->locate
.size
.var
);
2279 /* A subroutine of assign_parms. Given that this parameter is allocated
2280 stack space by the ABI, find it. */
2283 assign_parm_find_stack_rtl (tree parm
, struct assign_parm_data_one
*data
)
2285 rtx offset_rtx
, stack_parm
;
2286 unsigned int align
, boundary
;
2288 /* If we're passing this arg using a reg, make its stack home the
2289 aligned stack slot. */
2290 if (data
->entry_parm
)
2291 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.slot_offset
);
2293 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.offset
);
2295 stack_parm
= current_function_internal_arg_pointer
;
2296 if (offset_rtx
!= const0_rtx
)
2297 stack_parm
= gen_rtx_PLUS (Pmode
, stack_parm
, offset_rtx
);
2298 stack_parm
= gen_rtx_MEM (data
->promoted_mode
, stack_parm
);
2300 set_mem_attributes (stack_parm
, parm
, 1);
2302 boundary
= data
->locate
.boundary
;
2303 align
= BITS_PER_UNIT
;
2305 /* If we're padding upward, we know that the alignment of the slot
2306 is FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2307 intentionally forcing upward padding. Otherwise we have to come
2308 up with a guess at the alignment based on OFFSET_RTX. */
2309 if (data
->locate
.where_pad
!= downward
|| data
->entry_parm
)
2311 else if (GET_CODE (offset_rtx
) == CONST_INT
)
2313 align
= INTVAL (offset_rtx
) * BITS_PER_UNIT
| boundary
;
2314 align
= align
& -align
;
2316 set_mem_align (stack_parm
, align
);
2318 if (data
->entry_parm
)
2319 set_reg_attrs_for_parm (data
->entry_parm
, stack_parm
);
2321 data
->stack_parm
= stack_parm
;
2324 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2325 always valid and contiguous. */
2328 assign_parm_adjust_entry_rtl (struct assign_parm_data_one
*data
)
2330 rtx entry_parm
= data
->entry_parm
;
2331 rtx stack_parm
= data
->stack_parm
;
2333 /* If this parm was passed part in regs and part in memory, pretend it
2334 arrived entirely in memory by pushing the register-part onto the stack.
2335 In the special case of a DImode or DFmode that is split, we could put
2336 it together in a pseudoreg directly, but for now that's not worth
2338 if (data
->partial
!= 0)
2340 /* Handle calls that pass values in multiple non-contiguous
2341 locations. The Irix 6 ABI has examples of this. */
2342 if (GET_CODE (entry_parm
) == PARALLEL
)
2343 emit_group_store (validize_mem (stack_parm
), entry_parm
,
2345 int_size_in_bytes (data
->passed_type
));
2348 gcc_assert (data
->partial
% UNITS_PER_WORD
== 0);
2349 move_block_from_reg (REGNO (entry_parm
), validize_mem (stack_parm
),
2350 data
->partial
/ UNITS_PER_WORD
);
2353 entry_parm
= stack_parm
;
2356 /* If we didn't decide this parm came in a register, by default it came
2358 else if (entry_parm
== NULL
)
2359 entry_parm
= stack_parm
;
2361 /* When an argument is passed in multiple locations, we can't make use
2362 of this information, but we can save some copying if the whole argument
2363 is passed in a single register. */
2364 else if (GET_CODE (entry_parm
) == PARALLEL
2365 && data
->nominal_mode
!= BLKmode
2366 && data
->passed_mode
!= BLKmode
)
2368 size_t i
, len
= XVECLEN (entry_parm
, 0);
2370 for (i
= 0; i
< len
; i
++)
2371 if (XEXP (XVECEXP (entry_parm
, 0, i
), 0) != NULL_RTX
2372 && REG_P (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2373 && (GET_MODE (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2374 == data
->passed_mode
)
2375 && INTVAL (XEXP (XVECEXP (entry_parm
, 0, i
), 1)) == 0)
2377 entry_parm
= XEXP (XVECEXP (entry_parm
, 0, i
), 0);
2382 data
->entry_parm
= entry_parm
;
2385 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2386 always valid and properly aligned. */
2389 assign_parm_adjust_stack_rtl (struct assign_parm_data_one
*data
)
2391 rtx stack_parm
= data
->stack_parm
;
2393 /* If we can't trust the parm stack slot to be aligned enough for its
2394 ultimate type, don't use that slot after entry. We'll make another
2395 stack slot, if we need one. */
2397 && ((STRICT_ALIGNMENT
2398 && GET_MODE_ALIGNMENT (data
->nominal_mode
) > MEM_ALIGN (stack_parm
))
2399 || (data
->nominal_type
2400 && TYPE_ALIGN (data
->nominal_type
) > MEM_ALIGN (stack_parm
)
2401 && MEM_ALIGN (stack_parm
) < PREFERRED_STACK_BOUNDARY
)))
2404 /* If parm was passed in memory, and we need to convert it on entry,
2405 don't store it back in that same slot. */
2406 else if (data
->entry_parm
== stack_parm
2407 && data
->nominal_mode
!= BLKmode
2408 && data
->nominal_mode
!= data
->passed_mode
)
2411 /* If stack protection is in effect for this function, don't leave any
2412 pointers in their passed stack slots. */
2413 else if (cfun
->stack_protect_guard
2414 && (flag_stack_protect
== 2
2415 || data
->passed_pointer
2416 || POINTER_TYPE_P (data
->nominal_type
)))
2419 data
->stack_parm
= stack_parm
;
2422 /* A subroutine of assign_parms. Return true if the current parameter
2423 should be stored as a BLKmode in the current frame. */
2426 assign_parm_setup_block_p (struct assign_parm_data_one
*data
)
2428 if (data
->nominal_mode
== BLKmode
)
2430 if (GET_CODE (data
->entry_parm
) == PARALLEL
)
2433 #ifdef BLOCK_REG_PADDING
2434 /* Only assign_parm_setup_block knows how to deal with register arguments
2435 that are padded at the least significant end. */
2436 if (REG_P (data
->entry_parm
)
2437 && GET_MODE_SIZE (data
->promoted_mode
) < UNITS_PER_WORD
2438 && (BLOCK_REG_PADDING (data
->passed_mode
, data
->passed_type
, 1)
2439 == (BYTES_BIG_ENDIAN
? upward
: downward
)))
2446 /* A subroutine of assign_parms. Arrange for the parameter to be
2447 present and valid in DATA->STACK_RTL. */
2450 assign_parm_setup_block (struct assign_parm_data_all
*all
,
2451 tree parm
, struct assign_parm_data_one
*data
)
2453 rtx entry_parm
= data
->entry_parm
;
2454 rtx stack_parm
= data
->stack_parm
;
2456 HOST_WIDE_INT size_stored
;
2457 rtx orig_entry_parm
= entry_parm
;
2459 if (GET_CODE (entry_parm
) == PARALLEL
)
2460 entry_parm
= emit_group_move_into_temps (entry_parm
);
2462 /* If we've a non-block object that's nevertheless passed in parts,
2463 reconstitute it in register operations rather than on the stack. */
2464 if (GET_CODE (entry_parm
) == PARALLEL
2465 && data
->nominal_mode
!= BLKmode
)
2467 rtx elt0
= XEXP (XVECEXP (orig_entry_parm
, 0, 0), 0);
2469 if ((XVECLEN (entry_parm
, 0) > 1
2470 || hard_regno_nregs
[REGNO (elt0
)][GET_MODE (elt0
)] > 1)
2471 && use_register_for_decl (parm
))
2473 rtx parmreg
= gen_reg_rtx (data
->nominal_mode
);
2475 push_to_sequence (all
->conversion_insns
);
2477 /* For values returned in multiple registers, handle possible
2478 incompatible calls to emit_group_store.
2480 For example, the following would be invalid, and would have to
2481 be fixed by the conditional below:
2483 emit_group_store ((reg:SF), (parallel:DF))
2484 emit_group_store ((reg:SI), (parallel:DI))
2486 An example of this are doubles in e500 v2:
2487 (parallel:DF (expr_list (reg:SI) (const_int 0))
2488 (expr_list (reg:SI) (const_int 4))). */
2489 if (data
->nominal_mode
!= data
->passed_mode
)
2491 rtx t
= gen_reg_rtx (GET_MODE (entry_parm
));
2492 emit_group_store (t
, entry_parm
, NULL_TREE
,
2493 GET_MODE_SIZE (GET_MODE (entry_parm
)));
2494 convert_move (parmreg
, t
, 0);
2497 emit_group_store (parmreg
, entry_parm
, data
->nominal_type
,
2498 int_size_in_bytes (data
->nominal_type
));
2500 all
->conversion_insns
= get_insns ();
2503 SET_DECL_RTL (parm
, parmreg
);
2508 size
= int_size_in_bytes (data
->passed_type
);
2509 size_stored
= CEIL_ROUND (size
, UNITS_PER_WORD
);
2510 if (stack_parm
== 0)
2512 DECL_ALIGN (parm
) = MAX (DECL_ALIGN (parm
), BITS_PER_WORD
);
2513 stack_parm
= assign_stack_local (BLKmode
, size_stored
,
2515 if (GET_MODE_SIZE (GET_MODE (entry_parm
)) == size
)
2516 PUT_MODE (stack_parm
, GET_MODE (entry_parm
));
2517 set_mem_attributes (stack_parm
, parm
, 1);
2520 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2521 calls that pass values in multiple non-contiguous locations. */
2522 if (REG_P (entry_parm
) || GET_CODE (entry_parm
) == PARALLEL
)
2526 /* Note that we will be storing an integral number of words.
2527 So we have to be careful to ensure that we allocate an
2528 integral number of words. We do this above when we call
2529 assign_stack_local if space was not allocated in the argument
2530 list. If it was, this will not work if PARM_BOUNDARY is not
2531 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2532 if it becomes a problem. Exception is when BLKmode arrives
2533 with arguments not conforming to word_mode. */
2535 if (data
->stack_parm
== 0)
2537 else if (GET_CODE (entry_parm
) == PARALLEL
)
2540 gcc_assert (!size
|| !(PARM_BOUNDARY
% BITS_PER_WORD
));
2542 mem
= validize_mem (stack_parm
);
2544 /* Handle values in multiple non-contiguous locations. */
2545 if (GET_CODE (entry_parm
) == PARALLEL
)
2547 push_to_sequence (all
->conversion_insns
);
2548 emit_group_store (mem
, entry_parm
, data
->passed_type
, size
);
2549 all
->conversion_insns
= get_insns ();
2556 /* If SIZE is that of a mode no bigger than a word, just use
2557 that mode's store operation. */
2558 else if (size
<= UNITS_PER_WORD
)
2560 enum machine_mode mode
2561 = mode_for_size (size
* BITS_PER_UNIT
, MODE_INT
, 0);
2564 #ifdef BLOCK_REG_PADDING
2565 && (size
== UNITS_PER_WORD
2566 || (BLOCK_REG_PADDING (mode
, data
->passed_type
, 1)
2567 != (BYTES_BIG_ENDIAN
? upward
: downward
)))
2571 rtx reg
= gen_rtx_REG (mode
, REGNO (entry_parm
));
2572 emit_move_insn (change_address (mem
, mode
, 0), reg
);
2575 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
2576 machine must be aligned to the left before storing
2577 to memory. Note that the previous test doesn't
2578 handle all cases (e.g. SIZE == 3). */
2579 else if (size
!= UNITS_PER_WORD
2580 #ifdef BLOCK_REG_PADDING
2581 && (BLOCK_REG_PADDING (mode
, data
->passed_type
, 1)
2589 int by
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
2590 rtx reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
2592 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
,
2593 build_int_cst (NULL_TREE
, by
),
2595 tem
= change_address (mem
, word_mode
, 0);
2596 emit_move_insn (tem
, x
);
2599 move_block_from_reg (REGNO (entry_parm
), mem
,
2600 size_stored
/ UNITS_PER_WORD
);
2603 move_block_from_reg (REGNO (entry_parm
), mem
,
2604 size_stored
/ UNITS_PER_WORD
);
2606 else if (data
->stack_parm
== 0)
2608 push_to_sequence (all
->conversion_insns
);
2609 emit_block_move (stack_parm
, data
->entry_parm
, GEN_INT (size
),
2611 all
->conversion_insns
= get_insns ();
2615 data
->stack_parm
= stack_parm
;
2616 SET_DECL_RTL (parm
, stack_parm
);
2619 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
2620 parameter. Get it there. Perform all ABI specified conversions. */
2623 assign_parm_setup_reg (struct assign_parm_data_all
*all
, tree parm
,
2624 struct assign_parm_data_one
*data
)
2627 enum machine_mode promoted_nominal_mode
;
2628 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (parm
));
2629 bool did_conversion
= false;
2631 /* Store the parm in a pseudoregister during the function, but we may
2632 need to do it in a wider mode. */
2634 promoted_nominal_mode
2635 = promote_mode (data
->nominal_type
, data
->nominal_mode
, &unsignedp
, 0);
2637 parmreg
= gen_reg_rtx (promoted_nominal_mode
);
2639 if (!DECL_ARTIFICIAL (parm
))
2640 mark_user_reg (parmreg
);
2642 /* If this was an item that we received a pointer to,
2643 set DECL_RTL appropriately. */
2644 if (data
->passed_pointer
)
2646 rtx x
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data
->passed_type
)), parmreg
);
2647 set_mem_attributes (x
, parm
, 1);
2648 SET_DECL_RTL (parm
, x
);
2651 SET_DECL_RTL (parm
, parmreg
);
2653 /* Copy the value into the register. */
2654 if (data
->nominal_mode
!= data
->passed_mode
2655 || promoted_nominal_mode
!= data
->promoted_mode
)
2659 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
2660 mode, by the caller. We now have to convert it to
2661 NOMINAL_MODE, if different. However, PARMREG may be in
2662 a different mode than NOMINAL_MODE if it is being stored
2665 If ENTRY_PARM is a hard register, it might be in a register
2666 not valid for operating in its mode (e.g., an odd-numbered
2667 register for a DFmode). In that case, moves are the only
2668 thing valid, so we can't do a convert from there. This
2669 occurs when the calling sequence allow such misaligned
2672 In addition, the conversion may involve a call, which could
2673 clobber parameters which haven't been copied to pseudo
2674 registers yet. Therefore, we must first copy the parm to
2675 a pseudo reg here, and save the conversion until after all
2676 parameters have been moved. */
2678 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
2680 emit_move_insn (tempreg
, validize_mem (data
->entry_parm
));
2682 push_to_sequence (all
->conversion_insns
);
2683 tempreg
= convert_to_mode (data
->nominal_mode
, tempreg
, unsignedp
);
2685 if (GET_CODE (tempreg
) == SUBREG
2686 && GET_MODE (tempreg
) == data
->nominal_mode
2687 && REG_P (SUBREG_REG (tempreg
))
2688 && data
->nominal_mode
== data
->passed_mode
2689 && GET_MODE (SUBREG_REG (tempreg
)) == GET_MODE (data
->entry_parm
)
2690 && GET_MODE_SIZE (GET_MODE (tempreg
))
2691 < GET_MODE_SIZE (GET_MODE (data
->entry_parm
)))
2693 /* The argument is already sign/zero extended, so note it
2695 SUBREG_PROMOTED_VAR_P (tempreg
) = 1;
2696 SUBREG_PROMOTED_UNSIGNED_SET (tempreg
, unsignedp
);
2699 /* TREE_USED gets set erroneously during expand_assignment. */
2700 save_tree_used
= TREE_USED (parm
);
2701 expand_assignment (parm
, make_tree (data
->nominal_type
, tempreg
));
2702 TREE_USED (parm
) = save_tree_used
;
2703 all
->conversion_insns
= get_insns ();
2706 did_conversion
= true;
2709 emit_move_insn (parmreg
, validize_mem (data
->entry_parm
));
2711 /* If we were passed a pointer but the actual value can safely live
2712 in a register, put it in one. */
2713 if (data
->passed_pointer
2714 && TYPE_MODE (TREE_TYPE (parm
)) != BLKmode
2715 /* If by-reference argument was promoted, demote it. */
2716 && (TYPE_MODE (TREE_TYPE (parm
)) != GET_MODE (DECL_RTL (parm
))
2717 || use_register_for_decl (parm
)))
2719 /* We can't use nominal_mode, because it will have been set to
2720 Pmode above. We must use the actual mode of the parm. */
2721 parmreg
= gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm
)));
2722 mark_user_reg (parmreg
);
2724 if (GET_MODE (parmreg
) != GET_MODE (DECL_RTL (parm
)))
2726 rtx tempreg
= gen_reg_rtx (GET_MODE (DECL_RTL (parm
)));
2727 int unsigned_p
= TYPE_UNSIGNED (TREE_TYPE (parm
));
2729 push_to_sequence (all
->conversion_insns
);
2730 emit_move_insn (tempreg
, DECL_RTL (parm
));
2731 tempreg
= convert_to_mode (GET_MODE (parmreg
), tempreg
, unsigned_p
);
2732 emit_move_insn (parmreg
, tempreg
);
2733 all
->conversion_insns
= get_insns ();
2736 did_conversion
= true;
2739 emit_move_insn (parmreg
, DECL_RTL (parm
));
2741 SET_DECL_RTL (parm
, parmreg
);
2743 /* STACK_PARM is the pointer, not the parm, and PARMREG is
2745 data
->stack_parm
= NULL
;
2748 /* Mark the register as eliminable if we did no conversion and it was
2749 copied from memory at a fixed offset, and the arg pointer was not
2750 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
2751 offset formed an invalid address, such memory-equivalences as we
2752 make here would screw up life analysis for it. */
2753 if (data
->nominal_mode
== data
->passed_mode
2755 && data
->stack_parm
!= 0
2756 && MEM_P (data
->stack_parm
)
2757 && data
->locate
.offset
.var
== 0
2758 && reg_mentioned_p (virtual_incoming_args_rtx
,
2759 XEXP (data
->stack_parm
, 0)))
2761 rtx linsn
= get_last_insn ();
2764 /* Mark complex types separately. */
2765 if (GET_CODE (parmreg
) == CONCAT
)
2767 enum machine_mode submode
2768 = GET_MODE_INNER (GET_MODE (parmreg
));
2769 int regnor
= REGNO (XEXP (parmreg
, 0));
2770 int regnoi
= REGNO (XEXP (parmreg
, 1));
2771 rtx stackr
= adjust_address_nv (data
->stack_parm
, submode
, 0);
2772 rtx stacki
= adjust_address_nv (data
->stack_parm
, submode
,
2773 GET_MODE_SIZE (submode
));
2775 /* Scan backwards for the set of the real and
2777 for (sinsn
= linsn
; sinsn
!= 0;
2778 sinsn
= prev_nonnote_insn (sinsn
))
2780 set
= single_set (sinsn
);
2784 if (SET_DEST (set
) == regno_reg_rtx
[regnoi
])
2786 = gen_rtx_EXPR_LIST (REG_EQUIV
, stacki
,
2788 else if (SET_DEST (set
) == regno_reg_rtx
[regnor
])
2790 = gen_rtx_EXPR_LIST (REG_EQUIV
, stackr
,
2794 else if ((set
= single_set (linsn
)) != 0
2795 && SET_DEST (set
) == parmreg
)
2797 = gen_rtx_EXPR_LIST (REG_EQUIV
,
2798 data
->stack_parm
, REG_NOTES (linsn
));
2801 /* For pointer data type, suggest pointer register. */
2802 if (POINTER_TYPE_P (TREE_TYPE (parm
)))
2803 mark_reg_pointer (parmreg
,
2804 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
2807 /* A subroutine of assign_parms. Allocate stack space to hold the current
2808 parameter. Get it there. Perform all ABI specified conversions. */
2811 assign_parm_setup_stack (struct assign_parm_data_all
*all
, tree parm
,
2812 struct assign_parm_data_one
*data
)
2814 /* Value must be stored in the stack slot STACK_PARM during function
2816 bool to_conversion
= false;
2818 if (data
->promoted_mode
!= data
->nominal_mode
)
2820 /* Conversion is required. */
2821 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
2823 emit_move_insn (tempreg
, validize_mem (data
->entry_parm
));
2825 push_to_sequence (all
->conversion_insns
);
2826 to_conversion
= true;
2828 data
->entry_parm
= convert_to_mode (data
->nominal_mode
, tempreg
,
2829 TYPE_UNSIGNED (TREE_TYPE (parm
)));
2831 if (data
->stack_parm
)
2832 /* ??? This may need a big-endian conversion on sparc64. */
2834 = adjust_address (data
->stack_parm
, data
->nominal_mode
, 0);
2837 if (data
->entry_parm
!= data
->stack_parm
)
2841 if (data
->stack_parm
== 0)
2844 = assign_stack_local (GET_MODE (data
->entry_parm
),
2845 GET_MODE_SIZE (GET_MODE (data
->entry_parm
)),
2846 TYPE_ALIGN (data
->passed_type
));
2847 set_mem_attributes (data
->stack_parm
, parm
, 1);
2850 dest
= validize_mem (data
->stack_parm
);
2851 src
= validize_mem (data
->entry_parm
);
2855 /* Use a block move to handle potentially misaligned entry_parm. */
2857 push_to_sequence (all
->conversion_insns
);
2858 to_conversion
= true;
2860 emit_block_move (dest
, src
,
2861 GEN_INT (int_size_in_bytes (data
->passed_type
)),
2865 emit_move_insn (dest
, src
);
2870 all
->conversion_insns
= get_insns ();
2874 SET_DECL_RTL (parm
, data
->stack_parm
);
2877 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
2878 undo the frobbing that we did in assign_parms_augmented_arg_list. */
2881 assign_parms_unsplit_complex (struct assign_parm_data_all
*all
, tree fnargs
)
2884 tree orig_fnargs
= all
->orig_fnargs
;
2886 for (parm
= orig_fnargs
; parm
; parm
= TREE_CHAIN (parm
))
2888 if (TREE_CODE (TREE_TYPE (parm
)) == COMPLEX_TYPE
2889 && targetm
.calls
.split_complex_arg (TREE_TYPE (parm
)))
2891 rtx tmp
, real
, imag
;
2892 enum machine_mode inner
= GET_MODE_INNER (DECL_MODE (parm
));
2894 real
= DECL_RTL (fnargs
);
2895 imag
= DECL_RTL (TREE_CHAIN (fnargs
));
2896 if (inner
!= GET_MODE (real
))
2898 real
= gen_lowpart_SUBREG (inner
, real
);
2899 imag
= gen_lowpart_SUBREG (inner
, imag
);
2902 if (TREE_ADDRESSABLE (parm
))
2905 HOST_WIDE_INT size
= int_size_in_bytes (TREE_TYPE (parm
));
2907 /* split_complex_arg put the real and imag parts in
2908 pseudos. Move them to memory. */
2909 tmp
= assign_stack_local (DECL_MODE (parm
), size
,
2910 TYPE_ALIGN (TREE_TYPE (parm
)));
2911 set_mem_attributes (tmp
, parm
, 1);
2912 rmem
= adjust_address_nv (tmp
, inner
, 0);
2913 imem
= adjust_address_nv (tmp
, inner
, GET_MODE_SIZE (inner
));
2914 push_to_sequence (all
->conversion_insns
);
2915 emit_move_insn (rmem
, real
);
2916 emit_move_insn (imem
, imag
);
2917 all
->conversion_insns
= get_insns ();
2921 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
2922 SET_DECL_RTL (parm
, tmp
);
2924 real
= DECL_INCOMING_RTL (fnargs
);
2925 imag
= DECL_INCOMING_RTL (TREE_CHAIN (fnargs
));
2926 if (inner
!= GET_MODE (real
))
2928 real
= gen_lowpart_SUBREG (inner
, real
);
2929 imag
= gen_lowpart_SUBREG (inner
, imag
);
2931 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
2932 set_decl_incoming_rtl (parm
, tmp
);
2933 fnargs
= TREE_CHAIN (fnargs
);
2937 SET_DECL_RTL (parm
, DECL_RTL (fnargs
));
2938 set_decl_incoming_rtl (parm
, DECL_INCOMING_RTL (fnargs
));
2940 /* Set MEM_EXPR to the original decl, i.e. to PARM,
2941 instead of the copy of decl, i.e. FNARGS. */
2942 if (DECL_INCOMING_RTL (parm
) && MEM_P (DECL_INCOMING_RTL (parm
)))
2943 set_mem_expr (DECL_INCOMING_RTL (parm
), parm
);
2946 fnargs
= TREE_CHAIN (fnargs
);
2950 /* Assign RTL expressions to the function's parameters. This may involve
2951 copying them into registers and using those registers as the DECL_RTL. */
2954 assign_parms (tree fndecl
)
2956 struct assign_parm_data_all all
;
2959 current_function_internal_arg_pointer
2960 = targetm
.calls
.internal_arg_pointer ();
2962 assign_parms_initialize_all (&all
);
2963 fnargs
= assign_parms_augmented_arg_list (&all
);
2965 for (parm
= fnargs
; parm
; parm
= TREE_CHAIN (parm
))
2967 struct assign_parm_data_one data
;
2969 /* Extract the type of PARM; adjust it according to ABI. */
2970 assign_parm_find_data_types (&all
, parm
, &data
);
2972 /* Early out for errors and void parameters. */
2973 if (data
.passed_mode
== VOIDmode
)
2975 SET_DECL_RTL (parm
, const0_rtx
);
2976 DECL_INCOMING_RTL (parm
) = DECL_RTL (parm
);
2980 if (current_function_stdarg
&& !TREE_CHAIN (parm
))
2981 assign_parms_setup_varargs (&all
, &data
, false);
2983 /* Find out where the parameter arrives in this function. */
2984 assign_parm_find_entry_rtl (&all
, &data
);
2986 /* Find out where stack space for this parameter might be. */
2987 if (assign_parm_is_stack_parm (&all
, &data
))
2989 assign_parm_find_stack_rtl (parm
, &data
);
2990 assign_parm_adjust_entry_rtl (&data
);
2993 /* Record permanently how this parm was passed. */
2994 set_decl_incoming_rtl (parm
, data
.entry_parm
);
2996 /* Update info on where next arg arrives in registers. */
2997 FUNCTION_ARG_ADVANCE (all
.args_so_far
, data
.promoted_mode
,
2998 data
.passed_type
, data
.named_arg
);
3000 assign_parm_adjust_stack_rtl (&data
);
3002 if (assign_parm_setup_block_p (&data
))
3003 assign_parm_setup_block (&all
, parm
, &data
);
3004 else if (data
.passed_pointer
|| use_register_for_decl (parm
))
3005 assign_parm_setup_reg (&all
, parm
, &data
);
3007 assign_parm_setup_stack (&all
, parm
, &data
);
3010 if (targetm
.calls
.split_complex_arg
&& fnargs
!= all
.orig_fnargs
)
3011 assign_parms_unsplit_complex (&all
, fnargs
);
3013 /* Output all parameter conversion instructions (possibly including calls)
3014 now that all parameters have been copied out of hard registers. */
3015 emit_insn (all
.conversion_insns
);
3017 /* If we are receiving a struct value address as the first argument, set up
3018 the RTL for the function result. As this might require code to convert
3019 the transmitted address to Pmode, we do this here to ensure that possible
3020 preliminary conversions of the address have been emitted already. */
3021 if (all
.function_result_decl
)
3023 tree result
= DECL_RESULT (current_function_decl
);
3024 rtx addr
= DECL_RTL (all
.function_result_decl
);
3027 if (DECL_BY_REFERENCE (result
))
3031 addr
= convert_memory_address (Pmode
, addr
);
3032 x
= gen_rtx_MEM (DECL_MODE (result
), addr
);
3033 set_mem_attributes (x
, result
, 1);
3035 SET_DECL_RTL (result
, x
);
3038 /* We have aligned all the args, so add space for the pretend args. */
3039 current_function_pretend_args_size
= all
.pretend_args_size
;
3040 all
.stack_args_size
.constant
+= all
.extra_pretend_bytes
;
3041 current_function_args_size
= all
.stack_args_size
.constant
;
3043 /* Adjust function incoming argument size for alignment and
3046 #ifdef REG_PARM_STACK_SPACE
3047 current_function_args_size
= MAX (current_function_args_size
,
3048 REG_PARM_STACK_SPACE (fndecl
));
3051 current_function_args_size
= CEIL_ROUND (current_function_args_size
,
3052 PARM_BOUNDARY
/ BITS_PER_UNIT
);
3054 #ifdef ARGS_GROW_DOWNWARD
3055 current_function_arg_offset_rtx
3056 = (all
.stack_args_size
.var
== 0 ? GEN_INT (-all
.stack_args_size
.constant
)
3057 : expand_expr (size_diffop (all
.stack_args_size
.var
,
3058 size_int (-all
.stack_args_size
.constant
)),
3059 NULL_RTX
, VOIDmode
, 0));
3061 current_function_arg_offset_rtx
= ARGS_SIZE_RTX (all
.stack_args_size
);
3064 /* See how many bytes, if any, of its args a function should try to pop
3067 current_function_pops_args
= RETURN_POPS_ARGS (fndecl
, TREE_TYPE (fndecl
),
3068 current_function_args_size
);
3070 /* For stdarg.h function, save info about
3071 regs and stack space used by the named args. */
3073 current_function_args_info
= all
.args_so_far
;
3075 /* Set the rtx used for the function return value. Put this in its
3076 own variable so any optimizers that need this information don't have
3077 to include tree.h. Do this here so it gets done when an inlined
3078 function gets output. */
3080 current_function_return_rtx
3081 = (DECL_RTL_SET_P (DECL_RESULT (fndecl
))
3082 ? DECL_RTL (DECL_RESULT (fndecl
)) : NULL_RTX
);
3084 /* If scalar return value was computed in a pseudo-reg, or was a named
3085 return value that got dumped to the stack, copy that to the hard
3087 if (DECL_RTL_SET_P (DECL_RESULT (fndecl
)))
3089 tree decl_result
= DECL_RESULT (fndecl
);
3090 rtx decl_rtl
= DECL_RTL (decl_result
);
3092 if (REG_P (decl_rtl
)
3093 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
3094 : DECL_REGISTER (decl_result
))
3098 real_decl_rtl
= targetm
.calls
.function_value (TREE_TYPE (decl_result
),
3100 REG_FUNCTION_VALUE_P (real_decl_rtl
) = 1;
3101 /* The delay slot scheduler assumes that current_function_return_rtx
3102 holds the hard register containing the return value, not a
3103 temporary pseudo. */
3104 current_function_return_rtx
= real_decl_rtl
;
3109 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3110 For all seen types, gimplify their sizes. */
3113 gimplify_parm_type (tree
*tp
, int *walk_subtrees
, void *data
)
3120 if (POINTER_TYPE_P (t
))
3122 else if (TYPE_SIZE (t
) && !TREE_CONSTANT (TYPE_SIZE (t
))
3123 && !TYPE_SIZES_GIMPLIFIED (t
))
3125 gimplify_type_sizes (t
, (tree
*) data
);
3133 /* Gimplify the parameter list for current_function_decl. This involves
3134 evaluating SAVE_EXPRs of variable sized parameters and generating code
3135 to implement callee-copies reference parameters. Returns a list of
3136 statements to add to the beginning of the function, or NULL if nothing
3140 gimplify_parameters (void)
3142 struct assign_parm_data_all all
;
3143 tree fnargs
, parm
, stmts
= NULL
;
3145 assign_parms_initialize_all (&all
);
3146 fnargs
= assign_parms_augmented_arg_list (&all
);
3148 for (parm
= fnargs
; parm
; parm
= TREE_CHAIN (parm
))
3150 struct assign_parm_data_one data
;
3152 /* Extract the type of PARM; adjust it according to ABI. */
3153 assign_parm_find_data_types (&all
, parm
, &data
);
3155 /* Early out for errors and void parameters. */
3156 if (data
.passed_mode
== VOIDmode
|| DECL_SIZE (parm
) == NULL
)
3159 /* Update info on where next arg arrives in registers. */
3160 FUNCTION_ARG_ADVANCE (all
.args_so_far
, data
.promoted_mode
,
3161 data
.passed_type
, data
.named_arg
);
3163 /* ??? Once upon a time variable_size stuffed parameter list
3164 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3165 turned out to be less than manageable in the gimple world.
3166 Now we have to hunt them down ourselves. */
3167 walk_tree_without_duplicates (&data
.passed_type
,
3168 gimplify_parm_type
, &stmts
);
3170 if (!TREE_CONSTANT (DECL_SIZE (parm
)))
3172 gimplify_one_sizepos (&DECL_SIZE (parm
), &stmts
);
3173 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm
), &stmts
);
3176 if (data
.passed_pointer
)
3178 tree type
= TREE_TYPE (data
.passed_type
);
3179 if (reference_callee_copied (&all
.args_so_far
, TYPE_MODE (type
),
3180 type
, data
.named_arg
))
3184 /* For constant sized objects, this is trivial; for
3185 variable-sized objects, we have to play games. */
3186 if (TREE_CONSTANT (DECL_SIZE (parm
)))
3188 local
= create_tmp_var (type
, get_name (parm
));
3189 DECL_IGNORED_P (local
) = 0;
3193 tree ptr_type
, addr
, args
;
3195 ptr_type
= build_pointer_type (type
);
3196 addr
= create_tmp_var (ptr_type
, get_name (parm
));
3197 DECL_IGNORED_P (addr
) = 0;
3198 local
= build_fold_indirect_ref (addr
);
3200 args
= tree_cons (NULL
, DECL_SIZE_UNIT (parm
), NULL
);
3201 t
= built_in_decls
[BUILT_IN_ALLOCA
];
3202 t
= build_function_call_expr (t
, args
);
3203 t
= fold_convert (ptr_type
, t
);
3204 t
= build2 (MODIFY_EXPR
, void_type_node
, addr
, t
);
3205 gimplify_and_add (t
, &stmts
);
3208 t
= build2 (MODIFY_EXPR
, void_type_node
, local
, parm
);
3209 gimplify_and_add (t
, &stmts
);
3211 SET_DECL_VALUE_EXPR (parm
, local
);
3212 DECL_HAS_VALUE_EXPR_P (parm
) = 1;
3220 /* Indicate whether REGNO is an incoming argument to the current function
3221 that was promoted to a wider mode. If so, return the RTX for the
3222 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
3223 that REGNO is promoted from and whether the promotion was signed or
3227 promoted_input_arg (unsigned int regno
, enum machine_mode
*pmode
, int *punsignedp
)
3231 for (arg
= DECL_ARGUMENTS (current_function_decl
); arg
;
3232 arg
= TREE_CHAIN (arg
))
3233 if (REG_P (DECL_INCOMING_RTL (arg
))
3234 && REGNO (DECL_INCOMING_RTL (arg
)) == regno
3235 && TYPE_MODE (DECL_ARG_TYPE (arg
)) == TYPE_MODE (TREE_TYPE (arg
)))
3237 enum machine_mode mode
= TYPE_MODE (TREE_TYPE (arg
));
3238 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (arg
));
3240 mode
= promote_mode (TREE_TYPE (arg
), mode
, &unsignedp
, 1);
3241 if (mode
== GET_MODE (DECL_INCOMING_RTL (arg
))
3242 && mode
!= DECL_MODE (arg
))
3244 *pmode
= DECL_MODE (arg
);
3245 *punsignedp
= unsignedp
;
3246 return DECL_INCOMING_RTL (arg
);
3254 /* Compute the size and offset from the start of the stacked arguments for a
3255 parm passed in mode PASSED_MODE and with type TYPE.
3257 INITIAL_OFFSET_PTR points to the current offset into the stacked
3260 The starting offset and size for this parm are returned in
3261 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3262 nonzero, the offset is that of stack slot, which is returned in
3263 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3264 padding required from the initial offset ptr to the stack slot.
3266 IN_REGS is nonzero if the argument will be passed in registers. It will
3267 never be set if REG_PARM_STACK_SPACE is not defined.
3269 FNDECL is the function in which the argument was defined.
3271 There are two types of rounding that are done. The first, controlled by
3272 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
3273 list to be aligned to the specific boundary (in bits). This rounding
3274 affects the initial and starting offsets, but not the argument size.
3276 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3277 optionally rounds the size of the parm to PARM_BOUNDARY. The
3278 initial offset is not affected by this rounding, while the size always
3279 is and the starting offset may be. */
3281 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3282 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3283 callers pass in the total size of args so far as
3284 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
3287 locate_and_pad_parm (enum machine_mode passed_mode
, tree type
, int in_regs
,
3288 int partial
, tree fndecl ATTRIBUTE_UNUSED
,
3289 struct args_size
*initial_offset_ptr
,
3290 struct locate_and_pad_arg_data
*locate
)
3293 enum direction where_pad
;
3294 unsigned int boundary
;
3295 int reg_parm_stack_space
= 0;
3296 int part_size_in_regs
;
3298 #ifdef REG_PARM_STACK_SPACE
3299 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
3301 /* If we have found a stack parm before we reach the end of the
3302 area reserved for registers, skip that area. */
3305 if (reg_parm_stack_space
> 0)
3307 if (initial_offset_ptr
->var
)
3309 initial_offset_ptr
->var
3310 = size_binop (MAX_EXPR
, ARGS_SIZE_TREE (*initial_offset_ptr
),
3311 ssize_int (reg_parm_stack_space
));
3312 initial_offset_ptr
->constant
= 0;
3314 else if (initial_offset_ptr
->constant
< reg_parm_stack_space
)
3315 initial_offset_ptr
->constant
= reg_parm_stack_space
;
3318 #endif /* REG_PARM_STACK_SPACE */
3320 part_size_in_regs
= (reg_parm_stack_space
== 0 ? partial
: 0);
3323 = type
? size_in_bytes (type
) : size_int (GET_MODE_SIZE (passed_mode
));
3324 where_pad
= FUNCTION_ARG_PADDING (passed_mode
, type
);
3325 boundary
= FUNCTION_ARG_BOUNDARY (passed_mode
, type
);
3326 locate
->where_pad
= where_pad
;
3327 locate
->boundary
= boundary
;
3329 /* Remember if the outgoing parameter requires extra alignment on the
3330 calling function side. */
3331 if (boundary
> PREFERRED_STACK_BOUNDARY
)
3332 boundary
= PREFERRED_STACK_BOUNDARY
;
3333 if (cfun
->stack_alignment_needed
< boundary
)
3334 cfun
->stack_alignment_needed
= boundary
;
3336 #ifdef ARGS_GROW_DOWNWARD
3337 locate
->slot_offset
.constant
= -initial_offset_ptr
->constant
;
3338 if (initial_offset_ptr
->var
)
3339 locate
->slot_offset
.var
= size_binop (MINUS_EXPR
, ssize_int (0),
3340 initial_offset_ptr
->var
);
3344 if (where_pad
!= none
3345 && (!host_integerp (sizetree
, 1)
3346 || (tree_low_cst (sizetree
, 1) * BITS_PER_UNIT
) % PARM_BOUNDARY
))
3347 s2
= round_up (s2
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3348 SUB_PARM_SIZE (locate
->slot_offset
, s2
);
3351 locate
->slot_offset
.constant
+= part_size_in_regs
;
3354 #ifdef REG_PARM_STACK_SPACE
3355 || REG_PARM_STACK_SPACE (fndecl
) > 0
3358 pad_to_arg_alignment (&locate
->slot_offset
, boundary
,
3359 &locate
->alignment_pad
);
3361 locate
->size
.constant
= (-initial_offset_ptr
->constant
3362 - locate
->slot_offset
.constant
);
3363 if (initial_offset_ptr
->var
)
3364 locate
->size
.var
= size_binop (MINUS_EXPR
,
3365 size_binop (MINUS_EXPR
,
3367 initial_offset_ptr
->var
),
3368 locate
->slot_offset
.var
);
3370 /* Pad_below needs the pre-rounded size to know how much to pad
3372 locate
->offset
= locate
->slot_offset
;
3373 if (where_pad
== downward
)
3374 pad_below (&locate
->offset
, passed_mode
, sizetree
);
3376 #else /* !ARGS_GROW_DOWNWARD */
3378 #ifdef REG_PARM_STACK_SPACE
3379 || REG_PARM_STACK_SPACE (fndecl
) > 0
3382 pad_to_arg_alignment (initial_offset_ptr
, boundary
,
3383 &locate
->alignment_pad
);
3384 locate
->slot_offset
= *initial_offset_ptr
;
3386 #ifdef PUSH_ROUNDING
3387 if (passed_mode
!= BLKmode
)
3388 sizetree
= size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree
)));
3391 /* Pad_below needs the pre-rounded size to know how much to pad below
3392 so this must be done before rounding up. */
3393 locate
->offset
= locate
->slot_offset
;
3394 if (where_pad
== downward
)
3395 pad_below (&locate
->offset
, passed_mode
, sizetree
);
3397 if (where_pad
!= none
3398 && (!host_integerp (sizetree
, 1)
3399 || (tree_low_cst (sizetree
, 1) * BITS_PER_UNIT
) % PARM_BOUNDARY
))
3400 sizetree
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3402 ADD_PARM_SIZE (locate
->size
, sizetree
);
3404 locate
->size
.constant
-= part_size_in_regs
;
3405 #endif /* ARGS_GROW_DOWNWARD */
3408 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
3409 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
3412 pad_to_arg_alignment (struct args_size
*offset_ptr
, int boundary
,
3413 struct args_size
*alignment_pad
)
3415 tree save_var
= NULL_TREE
;
3416 HOST_WIDE_INT save_constant
= 0;
3417 int boundary_in_bytes
= boundary
/ BITS_PER_UNIT
;
3418 HOST_WIDE_INT sp_offset
= STACK_POINTER_OFFSET
;
3420 #ifdef SPARC_STACK_BOUNDARY_HACK
3421 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
3422 the real alignment of %sp. However, when it does this, the
3423 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
3424 if (SPARC_STACK_BOUNDARY_HACK
)
3428 if (boundary
> PARM_BOUNDARY
&& boundary
> STACK_BOUNDARY
)
3430 save_var
= offset_ptr
->var
;
3431 save_constant
= offset_ptr
->constant
;
3434 alignment_pad
->var
= NULL_TREE
;
3435 alignment_pad
->constant
= 0;
3437 if (boundary
> BITS_PER_UNIT
)
3439 if (offset_ptr
->var
)
3441 tree sp_offset_tree
= ssize_int (sp_offset
);
3442 tree offset
= size_binop (PLUS_EXPR
,
3443 ARGS_SIZE_TREE (*offset_ptr
),
3445 #ifdef ARGS_GROW_DOWNWARD
3446 tree rounded
= round_down (offset
, boundary
/ BITS_PER_UNIT
);
3448 tree rounded
= round_up (offset
, boundary
/ BITS_PER_UNIT
);
3451 offset_ptr
->var
= size_binop (MINUS_EXPR
, rounded
, sp_offset_tree
);
3452 /* ARGS_SIZE_TREE includes constant term. */
3453 offset_ptr
->constant
= 0;
3454 if (boundary
> PARM_BOUNDARY
&& boundary
> STACK_BOUNDARY
)
3455 alignment_pad
->var
= size_binop (MINUS_EXPR
, offset_ptr
->var
,
3460 offset_ptr
->constant
= -sp_offset
+
3461 #ifdef ARGS_GROW_DOWNWARD
3462 FLOOR_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
3464 CEIL_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
3466 if (boundary
> PARM_BOUNDARY
&& boundary
> STACK_BOUNDARY
)
3467 alignment_pad
->constant
= offset_ptr
->constant
- save_constant
;
3473 pad_below (struct args_size
*offset_ptr
, enum machine_mode passed_mode
, tree sizetree
)
3475 if (passed_mode
!= BLKmode
)
3477 if (GET_MODE_BITSIZE (passed_mode
) % PARM_BOUNDARY
)
3478 offset_ptr
->constant
3479 += (((GET_MODE_BITSIZE (passed_mode
) + PARM_BOUNDARY
- 1)
3480 / PARM_BOUNDARY
* PARM_BOUNDARY
/ BITS_PER_UNIT
)
3481 - GET_MODE_SIZE (passed_mode
));
3485 if (TREE_CODE (sizetree
) != INTEGER_CST
3486 || (TREE_INT_CST_LOW (sizetree
) * BITS_PER_UNIT
) % PARM_BOUNDARY
)
3488 /* Round the size up to multiple of PARM_BOUNDARY bits. */
3489 tree s2
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3491 ADD_PARM_SIZE (*offset_ptr
, s2
);
3492 SUB_PARM_SIZE (*offset_ptr
, sizetree
);
3497 /* Walk the tree of blocks describing the binding levels within a function
3498 and warn about variables the might be killed by setjmp or vfork.
3499 This is done after calling flow_analysis and before global_alloc
3500 clobbers the pseudo-regs to hard regs. */
3503 setjmp_vars_warning (tree block
)
3507 for (decl
= BLOCK_VARS (block
); decl
; decl
= TREE_CHAIN (decl
))
3509 if (TREE_CODE (decl
) == VAR_DECL
3510 && DECL_RTL_SET_P (decl
)
3511 && REG_P (DECL_RTL (decl
))
3512 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl
))))
3513 warning (0, "variable %q+D might be clobbered by %<longjmp%>"
3518 for (sub
= BLOCK_SUBBLOCKS (block
); sub
; sub
= TREE_CHAIN (sub
))
3519 setjmp_vars_warning (sub
);
3522 /* Do the appropriate part of setjmp_vars_warning
3523 but for arguments instead of local variables. */
3526 setjmp_args_warning (void)
3529 for (decl
= DECL_ARGUMENTS (current_function_decl
);
3530 decl
; decl
= TREE_CHAIN (decl
))
3531 if (DECL_RTL (decl
) != 0
3532 && REG_P (DECL_RTL (decl
))
3533 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl
))))
3534 warning (0, "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
3539 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
3540 and create duplicate blocks. */
3541 /* ??? Need an option to either create block fragments or to create
3542 abstract origin duplicates of a source block. It really depends
3543 on what optimization has been performed. */
3546 reorder_blocks (void)
3548 tree block
= DECL_INITIAL (current_function_decl
);
3549 VEC(tree
,heap
) *block_stack
;
3551 if (block
== NULL_TREE
)
3554 block_stack
= VEC_alloc (tree
, heap
, 10);
3556 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
3557 clear_block_marks (block
);
3559 /* Prune the old trees away, so that they don't get in the way. */
3560 BLOCK_SUBBLOCKS (block
) = NULL_TREE
;
3561 BLOCK_CHAIN (block
) = NULL_TREE
;
3563 /* Recreate the block tree from the note nesting. */
3564 reorder_blocks_1 (get_insns (), block
, &block_stack
);
3565 BLOCK_SUBBLOCKS (block
) = blocks_nreverse (BLOCK_SUBBLOCKS (block
));
3567 /* Remove deleted blocks from the block fragment chains. */
3568 reorder_fix_fragments (block
);
3570 VEC_free (tree
, heap
, block_stack
);
3573 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
3576 clear_block_marks (tree block
)
3580 TREE_ASM_WRITTEN (block
) = 0;
3581 clear_block_marks (BLOCK_SUBBLOCKS (block
));
3582 block
= BLOCK_CHAIN (block
);
3587 reorder_blocks_1 (rtx insns
, tree current_block
, VEC(tree
,heap
) **p_block_stack
)
3591 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
3595 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_BEG
)
3597 tree block
= NOTE_BLOCK (insn
);
3599 /* If we have seen this block before, that means it now
3600 spans multiple address regions. Create a new fragment. */
3601 if (TREE_ASM_WRITTEN (block
))
3603 tree new_block
= copy_node (block
);
3606 origin
= (BLOCK_FRAGMENT_ORIGIN (block
)
3607 ? BLOCK_FRAGMENT_ORIGIN (block
)
3609 BLOCK_FRAGMENT_ORIGIN (new_block
) = origin
;
3610 BLOCK_FRAGMENT_CHAIN (new_block
)
3611 = BLOCK_FRAGMENT_CHAIN (origin
);
3612 BLOCK_FRAGMENT_CHAIN (origin
) = new_block
;
3614 NOTE_BLOCK (insn
) = new_block
;
3618 BLOCK_SUBBLOCKS (block
) = 0;
3619 TREE_ASM_WRITTEN (block
) = 1;
3620 /* When there's only one block for the entire function,
3621 current_block == block and we mustn't do this, it
3622 will cause infinite recursion. */
3623 if (block
!= current_block
)
3625 BLOCK_SUPERCONTEXT (block
) = current_block
;
3626 BLOCK_CHAIN (block
) = BLOCK_SUBBLOCKS (current_block
);
3627 BLOCK_SUBBLOCKS (current_block
) = block
;
3628 current_block
= block
;
3630 VEC_safe_push (tree
, heap
, *p_block_stack
, block
);
3632 else if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_END
)
3634 NOTE_BLOCK (insn
) = VEC_pop (tree
, *p_block_stack
);
3635 BLOCK_SUBBLOCKS (current_block
)
3636 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block
));
3637 current_block
= BLOCK_SUPERCONTEXT (current_block
);
3643 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
3644 appears in the block tree, select one of the fragments to become
3645 the new origin block. */
3648 reorder_fix_fragments (tree block
)
3652 tree dup_origin
= BLOCK_FRAGMENT_ORIGIN (block
);
3653 tree new_origin
= NULL_TREE
;
3657 if (! TREE_ASM_WRITTEN (dup_origin
))
3659 new_origin
= BLOCK_FRAGMENT_CHAIN (dup_origin
);
3661 /* Find the first of the remaining fragments. There must
3662 be at least one -- the current block. */
3663 while (! TREE_ASM_WRITTEN (new_origin
))
3664 new_origin
= BLOCK_FRAGMENT_CHAIN (new_origin
);
3665 BLOCK_FRAGMENT_ORIGIN (new_origin
) = NULL_TREE
;
3668 else if (! dup_origin
)
3671 /* Re-root the rest of the fragments to the new origin. In the
3672 case that DUP_ORIGIN was null, that means BLOCK was the origin
3673 of a chain of fragments and we want to remove those fragments
3674 that didn't make it to the output. */
3677 tree
*pp
= &BLOCK_FRAGMENT_CHAIN (new_origin
);
3682 if (TREE_ASM_WRITTEN (chain
))
3684 BLOCK_FRAGMENT_ORIGIN (chain
) = new_origin
;
3686 pp
= &BLOCK_FRAGMENT_CHAIN (chain
);
3688 chain
= BLOCK_FRAGMENT_CHAIN (chain
);
3693 reorder_fix_fragments (BLOCK_SUBBLOCKS (block
));
3694 block
= BLOCK_CHAIN (block
);
3698 /* Reverse the order of elements in the chain T of blocks,
3699 and return the new head of the chain (old last element). */
3702 blocks_nreverse (tree t
)
3704 tree prev
= 0, decl
, next
;
3705 for (decl
= t
; decl
; decl
= next
)
3707 next
= BLOCK_CHAIN (decl
);
3708 BLOCK_CHAIN (decl
) = prev
;
3714 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
3715 non-NULL, list them all into VECTOR, in a depth-first preorder
3716 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
3720 all_blocks (tree block
, tree
*vector
)
3726 TREE_ASM_WRITTEN (block
) = 0;
3728 /* Record this block. */
3730 vector
[n_blocks
] = block
;
3734 /* Record the subblocks, and their subblocks... */
3735 n_blocks
+= all_blocks (BLOCK_SUBBLOCKS (block
),
3736 vector
? vector
+ n_blocks
: 0);
3737 block
= BLOCK_CHAIN (block
);
3743 /* Return a vector containing all the blocks rooted at BLOCK. The
3744 number of elements in the vector is stored in N_BLOCKS_P. The
3745 vector is dynamically allocated; it is the caller's responsibility
3746 to call `free' on the pointer returned. */
3749 get_block_vector (tree block
, int *n_blocks_p
)
3753 *n_blocks_p
= all_blocks (block
, NULL
);
3754 block_vector
= xmalloc (*n_blocks_p
* sizeof (tree
));
3755 all_blocks (block
, block_vector
);
3757 return block_vector
;
3760 static GTY(()) int next_block_index
= 2;
3762 /* Set BLOCK_NUMBER for all the blocks in FN. */
3765 number_blocks (tree fn
)
3771 /* For SDB and XCOFF debugging output, we start numbering the blocks
3772 from 1 within each function, rather than keeping a running
3774 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
3775 if (write_symbols
== SDB_DEBUG
|| write_symbols
== XCOFF_DEBUG
)
3776 next_block_index
= 1;
3779 block_vector
= get_block_vector (DECL_INITIAL (fn
), &n_blocks
);
3781 /* The top-level BLOCK isn't numbered at all. */
3782 for (i
= 1; i
< n_blocks
; ++i
)
3783 /* We number the blocks from two. */
3784 BLOCK_NUMBER (block_vector
[i
]) = next_block_index
++;
3786 free (block_vector
);
3791 /* If VAR is present in a subblock of BLOCK, return the subblock. */
3794 debug_find_var_in_block_tree (tree var
, tree block
)
3798 for (t
= BLOCK_VARS (block
); t
; t
= TREE_CHAIN (t
))
3802 for (t
= BLOCK_SUBBLOCKS (block
); t
; t
= TREE_CHAIN (t
))
3804 tree ret
= debug_find_var_in_block_tree (var
, t
);
3812 /* Allocate a function structure for FNDECL and set its contents
3816 allocate_struct_function (tree fndecl
)
3819 tree fntype
= fndecl
? TREE_TYPE (fndecl
) : NULL_TREE
;
3821 cfun
= ggc_alloc_cleared (sizeof (struct function
));
3823 cfun
->stack_alignment_needed
= STACK_BOUNDARY
;
3824 cfun
->preferred_stack_boundary
= STACK_BOUNDARY
;
3826 current_function_funcdef_no
= funcdef_no
++;
3828 cfun
->function_frequency
= FUNCTION_FREQUENCY_NORMAL
;
3830 init_eh_for_function ();
3832 lang_hooks
.function
.init (cfun
);
3833 if (init_machine_status
)
3834 cfun
->machine
= (*init_machine_status
) ();
3839 DECL_STRUCT_FUNCTION (fndecl
) = cfun
;
3840 cfun
->decl
= fndecl
;
3842 result
= DECL_RESULT (fndecl
);
3843 if (aggregate_value_p (result
, fndecl
))
3845 #ifdef PCC_STATIC_STRUCT_RETURN
3846 current_function_returns_pcc_struct
= 1;
3848 current_function_returns_struct
= 1;
3851 current_function_returns_pointer
= POINTER_TYPE_P (TREE_TYPE (result
));
3853 current_function_stdarg
3855 && TYPE_ARG_TYPES (fntype
) != 0
3856 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype
)))
3857 != void_type_node
));
3859 /* Assume all registers in stdarg functions need to be saved. */
3860 cfun
->va_list_gpr_size
= VA_LIST_MAX_GPR_SIZE
;
3861 cfun
->va_list_fpr_size
= VA_LIST_MAX_FPR_SIZE
;
3864 /* Reset cfun, and other non-struct-function variables to defaults as
3865 appropriate for emitting rtl at the start of a function. */
3868 prepare_function_start (tree fndecl
)
3870 if (fndecl
&& DECL_STRUCT_FUNCTION (fndecl
))
3871 cfun
= DECL_STRUCT_FUNCTION (fndecl
);
3873 allocate_struct_function (fndecl
);
3875 init_varasm_status (cfun
);
3878 cse_not_expected
= ! optimize
;
3880 /* Caller save not needed yet. */
3881 caller_save_needed
= 0;
3883 /* We haven't done register allocation yet. */
3886 /* Indicate that we have not instantiated virtual registers yet. */
3887 virtuals_instantiated
= 0;
3889 /* Indicate that we want CONCATs now. */
3890 generating_concat_p
= 1;
3892 /* Indicate we have no need of a frame pointer yet. */
3893 frame_pointer_needed
= 0;
3896 /* Initialize the rtl expansion mechanism so that we can do simple things
3897 like generate sequences. This is used to provide a context during global
3898 initialization of some passes. */
3900 init_dummy_function_start (void)
3902 prepare_function_start (NULL
);
3905 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
3906 and initialize static variables for generating RTL for the statements
3910 init_function_start (tree subr
)
3912 prepare_function_start (subr
);
3914 /* Prevent ever trying to delete the first instruction of a
3915 function. Also tell final how to output a linenum before the
3916 function prologue. Note linenums could be missing, e.g. when
3917 compiling a Java .class file. */
3918 if (! DECL_IS_BUILTIN (subr
))
3919 emit_line_note (DECL_SOURCE_LOCATION (subr
));
3921 /* Make sure first insn is a note even if we don't want linenums.
3922 This makes sure the first insn will never be deleted.
3923 Also, final expects a note to appear there. */
3924 emit_note (NOTE_INSN_DELETED
);
3926 /* Warn if this value is an aggregate type,
3927 regardless of which calling convention we are using for it. */
3928 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr
))))
3929 warning (OPT_Waggregate_return
, "function returns an aggregate");
3932 /* Make sure all values used by the optimization passes have sane
3935 init_function_for_compilation (void)
3939 /* No prologue/epilogue insns yet. Make sure that these vectors are
3941 gcc_assert (VEC_length (int, prologue
) == 0);
3942 gcc_assert (VEC_length (int, epilogue
) == 0);
3943 gcc_assert (VEC_length (int, sibcall_epilogue
) == 0);
3946 struct tree_opt_pass pass_init_function
=
3950 init_function_for_compilation
, /* execute */
3953 0, /* static_pass_number */
3955 0, /* properties_required */
3956 0, /* properties_provided */
3957 0, /* properties_destroyed */
3958 0, /* todo_flags_start */
3959 0, /* todo_flags_finish */
3965 expand_main_function (void)
3967 #if (defined(INVOKE__main) \
3968 || (!defined(HAS_INIT_SECTION) \
3969 && !defined(INIT_SECTION_ASM_OP) \
3970 && !defined(INIT_ARRAY_SECTION_ASM_OP)))
3971 emit_library_call (init_one_libfunc (NAME__MAIN
), LCT_NORMAL
, VOIDmode
, 0);
3975 /* Expand code to initialize the stack_protect_guard. This is invoked at
3976 the beginning of a function to be protected. */
3978 #ifndef HAVE_stack_protect_set
3979 # define HAVE_stack_protect_set 0
3980 # define gen_stack_protect_set(x,y) (gcc_unreachable (), NULL_RTX)
3984 stack_protect_prologue (void)
3986 tree guard_decl
= targetm
.stack_protect_guard ();
3989 /* Avoid expand_expr here, because we don't want guard_decl pulled
3990 into registers unless absolutely necessary. And we know that
3991 cfun->stack_protect_guard is a local stack slot, so this skips
3993 x
= validize_mem (DECL_RTL (cfun
->stack_protect_guard
));
3994 y
= validize_mem (DECL_RTL (guard_decl
));
3996 /* Allow the target to copy from Y to X without leaking Y into a
3998 if (HAVE_stack_protect_set
)
4000 rtx insn
= gen_stack_protect_set (x
, y
);
4008 /* Otherwise do a straight move. */
4009 emit_move_insn (x
, y
);
4012 /* Expand code to verify the stack_protect_guard. This is invoked at
4013 the end of a function to be protected. */
4015 #ifndef HAVE_stack_protect_test
4016 # define HAVE_stack_protect_test 0
4017 # define gen_stack_protect_test(x, y, z) (gcc_unreachable (), NULL_RTX)
4021 stack_protect_epilogue (void)
4023 tree guard_decl
= targetm
.stack_protect_guard ();
4024 rtx label
= gen_label_rtx ();
4027 /* Avoid expand_expr here, because we don't want guard_decl pulled
4028 into registers unless absolutely necessary. And we know that
4029 cfun->stack_protect_guard is a local stack slot, so this skips
4031 x
= validize_mem (DECL_RTL (cfun
->stack_protect_guard
));
4032 y
= validize_mem (DECL_RTL (guard_decl
));
4034 /* Allow the target to compare Y with X without leaking either into
4036 switch (HAVE_stack_protect_test
!= 0)
4039 tmp
= gen_stack_protect_test (x
, y
, label
);
4048 emit_cmp_and_jump_insns (x
, y
, EQ
, NULL_RTX
, ptr_mode
, 1, label
);
4052 /* The noreturn predictor has been moved to the tree level. The rtl-level
4053 predictors estimate this branch about 20%, which isn't enough to get
4054 things moved out of line. Since this is the only extant case of adding
4055 a noreturn function at the rtl level, it doesn't seem worth doing ought
4056 except adding the prediction by hand. */
4057 tmp
= get_last_insn ();
4059 predict_insn_def (tmp
, PRED_NORETURN
, TAKEN
);
4061 expand_expr_stmt (targetm
.stack_protect_fail ());
4065 /* Start the RTL for a new function, and set variables used for
4067 SUBR is the FUNCTION_DECL node.
4068 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4069 the function's parameters, which must be run at any return statement. */
4072 expand_function_start (tree subr
)
4074 /* Make sure volatile mem refs aren't considered
4075 valid operands of arithmetic insns. */
4076 init_recog_no_volatile ();
4078 current_function_profile
4080 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr
));
4082 current_function_limit_stack
4083 = (stack_limit_rtx
!= NULL_RTX
&& ! DECL_NO_LIMIT_STACK (subr
));
4085 /* Make the label for return statements to jump to. Do not special
4086 case machines with special return instructions -- they will be
4087 handled later during jump, ifcvt, or epilogue creation. */
4088 return_label
= gen_label_rtx ();
4090 /* Initialize rtx used to return the value. */
4091 /* Do this before assign_parms so that we copy the struct value address
4092 before any library calls that assign parms might generate. */
4094 /* Decide whether to return the value in memory or in a register. */
4095 if (aggregate_value_p (DECL_RESULT (subr
), subr
))
4097 /* Returning something that won't go in a register. */
4098 rtx value_address
= 0;
4100 #ifdef PCC_STATIC_STRUCT_RETURN
4101 if (current_function_returns_pcc_struct
)
4103 int size
= int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr
)));
4104 value_address
= assemble_static_space (size
);
4109 rtx sv
= targetm
.calls
.struct_value_rtx (TREE_TYPE (subr
), 1);
4110 /* Expect to be passed the address of a place to store the value.
4111 If it is passed as an argument, assign_parms will take care of
4115 value_address
= gen_reg_rtx (Pmode
);
4116 emit_move_insn (value_address
, sv
);
4121 rtx x
= value_address
;
4122 if (!DECL_BY_REFERENCE (DECL_RESULT (subr
)))
4124 x
= gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr
)), x
);
4125 set_mem_attributes (x
, DECL_RESULT (subr
), 1);
4127 SET_DECL_RTL (DECL_RESULT (subr
), x
);
4130 else if (DECL_MODE (DECL_RESULT (subr
)) == VOIDmode
)
4131 /* If return mode is void, this decl rtl should not be used. */
4132 SET_DECL_RTL (DECL_RESULT (subr
), NULL_RTX
);
4135 /* Compute the return values into a pseudo reg, which we will copy
4136 into the true return register after the cleanups are done. */
4137 tree return_type
= TREE_TYPE (DECL_RESULT (subr
));
4138 if (TYPE_MODE (return_type
) != BLKmode
4139 && targetm
.calls
.return_in_msb (return_type
))
4140 /* expand_function_end will insert the appropriate padding in
4141 this case. Use the return value's natural (unpadded) mode
4142 within the function proper. */
4143 SET_DECL_RTL (DECL_RESULT (subr
),
4144 gen_reg_rtx (TYPE_MODE (return_type
)));
4147 /* In order to figure out what mode to use for the pseudo, we
4148 figure out what the mode of the eventual return register will
4149 actually be, and use that. */
4150 rtx hard_reg
= hard_function_value (return_type
, subr
, 0, 1);
4152 /* Structures that are returned in registers are not
4153 aggregate_value_p, so we may see a PARALLEL or a REG. */
4154 if (REG_P (hard_reg
))
4155 SET_DECL_RTL (DECL_RESULT (subr
),
4156 gen_reg_rtx (GET_MODE (hard_reg
)));
4159 gcc_assert (GET_CODE (hard_reg
) == PARALLEL
);
4160 SET_DECL_RTL (DECL_RESULT (subr
), gen_group_rtx (hard_reg
));
4164 /* Set DECL_REGISTER flag so that expand_function_end will copy the
4165 result to the real return register(s). */
4166 DECL_REGISTER (DECL_RESULT (subr
)) = 1;
4169 /* Initialize rtx for parameters and local variables.
4170 In some cases this requires emitting insns. */
4171 assign_parms (subr
);
4173 /* If function gets a static chain arg, store it. */
4174 if (cfun
->static_chain_decl
)
4176 tree parm
= cfun
->static_chain_decl
;
4177 rtx local
= gen_reg_rtx (Pmode
);
4179 set_decl_incoming_rtl (parm
, static_chain_incoming_rtx
);
4180 SET_DECL_RTL (parm
, local
);
4181 mark_reg_pointer (local
, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
4183 emit_move_insn (local
, static_chain_incoming_rtx
);
4186 /* If the function receives a non-local goto, then store the
4187 bits we need to restore the frame pointer. */
4188 if (cfun
->nonlocal_goto_save_area
)
4193 /* ??? We need to do this save early. Unfortunately here is
4194 before the frame variable gets declared. Help out... */
4195 expand_var (TREE_OPERAND (cfun
->nonlocal_goto_save_area
, 0));
4197 t_save
= build4 (ARRAY_REF
, ptr_type_node
,
4198 cfun
->nonlocal_goto_save_area
,
4199 integer_zero_node
, NULL_TREE
, NULL_TREE
);
4200 r_save
= expand_expr (t_save
, NULL_RTX
, VOIDmode
, EXPAND_WRITE
);
4201 r_save
= convert_memory_address (Pmode
, r_save
);
4203 emit_move_insn (r_save
, virtual_stack_vars_rtx
);
4204 update_nonlocal_goto_save_area ();
4207 /* The following was moved from init_function_start.
4208 The move is supposed to make sdb output more accurate. */
4209 /* Indicate the beginning of the function body,
4210 as opposed to parm setup. */
4211 emit_note (NOTE_INSN_FUNCTION_BEG
);
4213 if (!NOTE_P (get_last_insn ()))
4214 emit_note (NOTE_INSN_DELETED
);
4215 parm_birth_insn
= get_last_insn ();
4217 if (current_function_profile
)
4220 PROFILE_HOOK (current_function_funcdef_no
);
4224 /* After the display initializations is where the tail-recursion label
4225 should go, if we end up needing one. Ensure we have a NOTE here
4226 since some things (like trampolines) get placed before this. */
4227 tail_recursion_reentry
= emit_note (NOTE_INSN_DELETED
);
4229 /* Make sure there is a line number after the function entry setup code. */
4230 force_next_line_note ();
4233 /* Undo the effects of init_dummy_function_start. */
4235 expand_dummy_function_end (void)
4237 /* End any sequences that failed to be closed due to syntax errors. */
4238 while (in_sequence_p ())
4241 /* Outside function body, can't compute type's actual size
4242 until next function's body starts. */
4244 free_after_parsing (cfun
);
4245 free_after_compilation (cfun
);
4249 /* Call DOIT for each hard register used as a return value from
4250 the current function. */
4253 diddle_return_value (void (*doit
) (rtx
, void *), void *arg
)
4255 rtx outgoing
= current_function_return_rtx
;
4260 if (REG_P (outgoing
))
4261 (*doit
) (outgoing
, arg
);
4262 else if (GET_CODE (outgoing
) == PARALLEL
)
4266 for (i
= 0; i
< XVECLEN (outgoing
, 0); i
++)
4268 rtx x
= XEXP (XVECEXP (outgoing
, 0, i
), 0);
4270 if (REG_P (x
) && REGNO (x
) < FIRST_PSEUDO_REGISTER
)
4277 do_clobber_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
4279 emit_insn (gen_rtx_CLOBBER (VOIDmode
, reg
));
4283 clobber_return_register (void)
4285 diddle_return_value (do_clobber_return_reg
, NULL
);
4287 /* In case we do use pseudo to return value, clobber it too. */
4288 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
4290 tree decl_result
= DECL_RESULT (current_function_decl
);
4291 rtx decl_rtl
= DECL_RTL (decl_result
);
4292 if (REG_P (decl_rtl
) && REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
)
4294 do_clobber_return_reg (decl_rtl
, NULL
);
4300 do_use_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
4302 emit_insn (gen_rtx_USE (VOIDmode
, reg
));
4306 use_return_register (void)
4308 diddle_return_value (do_use_return_reg
, NULL
);
4311 /* Possibly warn about unused parameters. */
4313 do_warn_unused_parameter (tree fn
)
4317 for (decl
= DECL_ARGUMENTS (fn
);
4318 decl
; decl
= TREE_CHAIN (decl
))
4319 if (!TREE_USED (decl
) && TREE_CODE (decl
) == PARM_DECL
4320 && DECL_NAME (decl
) && !DECL_ARTIFICIAL (decl
))
4321 warning (OPT_Wunused_parameter
, "unused parameter %q+D", decl
);
4324 static GTY(()) rtx initial_trampoline
;
4326 /* Generate RTL for the end of the current function. */
4329 expand_function_end (void)
4333 /* If arg_pointer_save_area was referenced only from a nested
4334 function, we will not have initialized it yet. Do that now. */
4335 if (arg_pointer_save_area
&& ! cfun
->arg_pointer_save_area_init
)
4336 get_arg_pointer_save_area (cfun
);
4338 /* If we are doing stack checking and this function makes calls,
4339 do a stack probe at the start of the function to ensure we have enough
4340 space for another stack frame. */
4341 if (flag_stack_check
&& ! STACK_CHECK_BUILTIN
)
4345 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
4349 probe_stack_range (STACK_CHECK_PROTECT
,
4350 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE
));
4353 emit_insn_before (seq
, tail_recursion_reentry
);
4358 /* Possibly warn about unused parameters.
4359 When frontend does unit-at-a-time, the warning is already
4360 issued at finalization time. */
4361 if (warn_unused_parameter
4362 && !lang_hooks
.callgraph
.expand_function
)
4363 do_warn_unused_parameter (current_function_decl
);
4365 /* End any sequences that failed to be closed due to syntax errors. */
4366 while (in_sequence_p ())
4369 clear_pending_stack_adjust ();
4370 do_pending_stack_adjust ();
4372 /* Mark the end of the function body.
4373 If control reaches this insn, the function can drop through
4374 without returning a value. */
4375 emit_note (NOTE_INSN_FUNCTION_END
);
4377 /* Must mark the last line number note in the function, so that the test
4378 coverage code can avoid counting the last line twice. This just tells
4379 the code to ignore the immediately following line note, since there
4380 already exists a copy of this note somewhere above. This line number
4381 note is still needed for debugging though, so we can't delete it. */
4382 if (flag_test_coverage
)
4383 emit_note (NOTE_INSN_REPEATED_LINE_NUMBER
);
4385 /* Output a linenumber for the end of the function.
4386 SDB depends on this. */
4387 force_next_line_note ();
4388 emit_line_note (input_location
);
4390 /* Before the return label (if any), clobber the return
4391 registers so that they are not propagated live to the rest of
4392 the function. This can only happen with functions that drop
4393 through; if there had been a return statement, there would
4394 have either been a return rtx, or a jump to the return label.
4396 We delay actual code generation after the current_function_value_rtx
4398 clobber_after
= get_last_insn ();
4400 /* Output the label for the actual return from the function. */
4401 emit_label (return_label
);
4403 if (USING_SJLJ_EXCEPTIONS
)
4405 /* Let except.c know where it should emit the call to unregister
4406 the function context for sjlj exceptions. */
4407 if (flag_exceptions
)
4408 sjlj_emit_function_exit_after (get_last_insn ());
4412 /* @@@ This is a kludge. We want to ensure that instructions that
4413 may trap are not moved into the epilogue by scheduling, because
4414 we don't always emit unwind information for the epilogue.
4415 However, not all machine descriptions define a blockage insn, so
4416 emit an ASM_INPUT to act as one. */
4417 if (flag_non_call_exceptions
)
4418 emit_insn (gen_rtx_ASM_INPUT (VOIDmode
, ""));
4421 /* If this is an implementation of throw, do what's necessary to
4422 communicate between __builtin_eh_return and the epilogue. */
4423 expand_eh_return ();
4425 /* If scalar return value was computed in a pseudo-reg, or was a named
4426 return value that got dumped to the stack, copy that to the hard
4428 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
4430 tree decl_result
= DECL_RESULT (current_function_decl
);
4431 rtx decl_rtl
= DECL_RTL (decl_result
);
4433 if (REG_P (decl_rtl
)
4434 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
4435 : DECL_REGISTER (decl_result
))
4437 rtx real_decl_rtl
= current_function_return_rtx
;
4439 /* This should be set in assign_parms. */
4440 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl
));
4442 /* If this is a BLKmode structure being returned in registers,
4443 then use the mode computed in expand_return. Note that if
4444 decl_rtl is memory, then its mode may have been changed,
4445 but that current_function_return_rtx has not. */
4446 if (GET_MODE (real_decl_rtl
) == BLKmode
)
4447 PUT_MODE (real_decl_rtl
, GET_MODE (decl_rtl
));
4449 /* If a non-BLKmode return value should be padded at the least
4450 significant end of the register, shift it left by the appropriate
4451 amount. BLKmode results are handled using the group load/store
4453 if (TYPE_MODE (TREE_TYPE (decl_result
)) != BLKmode
4454 && targetm
.calls
.return_in_msb (TREE_TYPE (decl_result
)))
4456 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl
),
4457 REGNO (real_decl_rtl
)),
4459 shift_return_value (GET_MODE (decl_rtl
), true, real_decl_rtl
);
4461 /* If a named return value dumped decl_return to memory, then
4462 we may need to re-do the PROMOTE_MODE signed/unsigned
4464 else if (GET_MODE (real_decl_rtl
) != GET_MODE (decl_rtl
))
4466 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (decl_result
));
4468 if (targetm
.calls
.promote_function_return (TREE_TYPE (current_function_decl
)))
4469 promote_mode (TREE_TYPE (decl_result
), GET_MODE (decl_rtl
),
4472 convert_move (real_decl_rtl
, decl_rtl
, unsignedp
);
4474 else if (GET_CODE (real_decl_rtl
) == PARALLEL
)
4476 /* If expand_function_start has created a PARALLEL for decl_rtl,
4477 move the result to the real return registers. Otherwise, do
4478 a group load from decl_rtl for a named return. */
4479 if (GET_CODE (decl_rtl
) == PARALLEL
)
4480 emit_group_move (real_decl_rtl
, decl_rtl
);
4482 emit_group_load (real_decl_rtl
, decl_rtl
,
4483 TREE_TYPE (decl_result
),
4484 int_size_in_bytes (TREE_TYPE (decl_result
)));
4486 /* In the case of complex integer modes smaller than a word, we'll
4487 need to generate some non-trivial bitfield insertions. Do that
4488 on a pseudo and not the hard register. */
4489 else if (GET_CODE (decl_rtl
) == CONCAT
4490 && GET_MODE_CLASS (GET_MODE (decl_rtl
)) == MODE_COMPLEX_INT
4491 && GET_MODE_BITSIZE (GET_MODE (decl_rtl
)) <= BITS_PER_WORD
)
4493 int old_generating_concat_p
;
4496 old_generating_concat_p
= generating_concat_p
;
4497 generating_concat_p
= 0;
4498 tmp
= gen_reg_rtx (GET_MODE (decl_rtl
));
4499 generating_concat_p
= old_generating_concat_p
;
4501 emit_move_insn (tmp
, decl_rtl
);
4502 emit_move_insn (real_decl_rtl
, tmp
);
4505 emit_move_insn (real_decl_rtl
, decl_rtl
);
4509 /* If returning a structure, arrange to return the address of the value
4510 in a place where debuggers expect to find it.
4512 If returning a structure PCC style,
4513 the caller also depends on this value.
4514 And current_function_returns_pcc_struct is not necessarily set. */
4515 if (current_function_returns_struct
4516 || current_function_returns_pcc_struct
)
4518 rtx value_address
= DECL_RTL (DECL_RESULT (current_function_decl
));
4519 tree type
= TREE_TYPE (DECL_RESULT (current_function_decl
));
4522 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl
)))
4523 type
= TREE_TYPE (type
);
4525 value_address
= XEXP (value_address
, 0);
4527 outgoing
= targetm
.calls
.function_value (build_pointer_type (type
),
4528 current_function_decl
, true);
4530 /* Mark this as a function return value so integrate will delete the
4531 assignment and USE below when inlining this function. */
4532 REG_FUNCTION_VALUE_P (outgoing
) = 1;
4534 /* The address may be ptr_mode and OUTGOING may be Pmode. */
4535 value_address
= convert_memory_address (GET_MODE (outgoing
),
4538 emit_move_insn (outgoing
, value_address
);
4540 /* Show return register used to hold result (in this case the address
4542 current_function_return_rtx
= outgoing
;
4545 /* Emit the actual code to clobber return register. */
4550 clobber_return_register ();
4551 expand_naked_return ();
4555 emit_insn_after (seq
, clobber_after
);
4558 /* Output the label for the naked return from the function. */
4559 emit_label (naked_return_label
);
4561 /* If stack protection is enabled for this function, check the guard. */
4562 if (cfun
->stack_protect_guard
)
4563 stack_protect_epilogue ();
4565 /* If we had calls to alloca, and this machine needs
4566 an accurate stack pointer to exit the function,
4567 insert some code to save and restore the stack pointer. */
4568 if (! EXIT_IGNORE_STACK
4569 && current_function_calls_alloca
)
4573 emit_stack_save (SAVE_FUNCTION
, &tem
, parm_birth_insn
);
4574 emit_stack_restore (SAVE_FUNCTION
, tem
, NULL_RTX
);
4577 /* ??? This should no longer be necessary since stupid is no longer with
4578 us, but there are some parts of the compiler (eg reload_combine, and
4579 sh mach_dep_reorg) that still try and compute their own lifetime info
4580 instead of using the general framework. */
4581 use_return_register ();
4585 get_arg_pointer_save_area (struct function
*f
)
4587 rtx ret
= f
->x_arg_pointer_save_area
;
4591 ret
= assign_stack_local_1 (Pmode
, GET_MODE_SIZE (Pmode
), 0, f
);
4592 f
->x_arg_pointer_save_area
= ret
;
4595 if (f
== cfun
&& ! f
->arg_pointer_save_area_init
)
4599 /* Save the arg pointer at the beginning of the function. The
4600 generated stack slot may not be a valid memory address, so we
4601 have to check it and fix it if necessary. */
4603 emit_move_insn (validize_mem (ret
), virtual_incoming_args_rtx
);
4607 push_topmost_sequence ();
4608 emit_insn_after (seq
, entry_of_function ());
4609 pop_topmost_sequence ();
4615 /* Extend a vector that records the INSN_UIDs of INSNS
4616 (a list of one or more insns). */
4619 record_insns (rtx insns
, VEC(int,heap
) **vecp
)
4623 for (tmp
= insns
; tmp
!= NULL_RTX
; tmp
= NEXT_INSN (tmp
))
4624 VEC_safe_push (int, heap
, *vecp
, INSN_UID (tmp
));
4627 /* Set the locator of the insn chain starting at INSN to LOC. */
4629 set_insn_locators (rtx insn
, int loc
)
4631 while (insn
!= NULL_RTX
)
4634 INSN_LOCATOR (insn
) = loc
;
4635 insn
= NEXT_INSN (insn
);
4639 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
4640 be running after reorg, SEQUENCE rtl is possible. */
4643 contains (rtx insn
, VEC(int,heap
) **vec
)
4647 if (NONJUMP_INSN_P (insn
)
4648 && GET_CODE (PATTERN (insn
)) == SEQUENCE
)
4651 for (i
= XVECLEN (PATTERN (insn
), 0) - 1; i
>= 0; i
--)
4652 for (j
= VEC_length (int, *vec
) - 1; j
>= 0; --j
)
4653 if (INSN_UID (XVECEXP (PATTERN (insn
), 0, i
))
4654 == VEC_index (int, *vec
, j
))
4660 for (j
= VEC_length (int, *vec
) - 1; j
>= 0; --j
)
4661 if (INSN_UID (insn
) == VEC_index (int, *vec
, j
))
4668 prologue_epilogue_contains (rtx insn
)
4670 if (contains (insn
, &prologue
))
4672 if (contains (insn
, &epilogue
))
4678 sibcall_epilogue_contains (rtx insn
)
4680 if (sibcall_epilogue
)
4681 return contains (insn
, &sibcall_epilogue
);
4686 /* Insert gen_return at the end of block BB. This also means updating
4687 block_for_insn appropriately. */
4690 emit_return_into_block (basic_block bb
, rtx line_note
)
4692 emit_jump_insn_after (gen_return (), BB_END (bb
));
4694 emit_note_copy_after (line_note
, PREV_INSN (BB_END (bb
)));
4696 #endif /* HAVE_return */
4698 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
4700 /* These functions convert the epilogue into a variant that does not
4701 modify the stack pointer. This is used in cases where a function
4702 returns an object whose size is not known until it is computed.
4703 The called function leaves the object on the stack, leaves the
4704 stack depressed, and returns a pointer to the object.
4706 What we need to do is track all modifications and references to the
4707 stack pointer, deleting the modifications and changing the
4708 references to point to the location the stack pointer would have
4709 pointed to had the modifications taken place.
4711 These functions need to be portable so we need to make as few
4712 assumptions about the epilogue as we can. However, the epilogue
4713 basically contains three things: instructions to reset the stack
4714 pointer, instructions to reload registers, possibly including the
4715 frame pointer, and an instruction to return to the caller.
4717 We must be sure of what a relevant epilogue insn is doing. We also
4718 make no attempt to validate the insns we make since if they are
4719 invalid, we probably can't do anything valid. The intent is that
4720 these routines get "smarter" as more and more machines start to use
4721 them and they try operating on different epilogues.
4723 We use the following structure to track what the part of the
4724 epilogue that we've already processed has done. We keep two copies
4725 of the SP equivalence, one for use during the insn we are
4726 processing and one for use in the next insn. The difference is
4727 because one part of a PARALLEL may adjust SP and the other may use
4732 rtx sp_equiv_reg
; /* REG that SP is set from, perhaps SP. */
4733 HOST_WIDE_INT sp_offset
; /* Offset from SP_EQUIV_REG of present SP. */
4734 rtx new_sp_equiv_reg
; /* REG to be used at end of insn. */
4735 HOST_WIDE_INT new_sp_offset
; /* Offset to be used at end of insn. */
4736 rtx equiv_reg_src
; /* If nonzero, the value that SP_EQUIV_REG
4737 should be set to once we no longer need
4739 rtx const_equiv
[FIRST_PSEUDO_REGISTER
]; /* Any known constant equivalences
4743 static void handle_epilogue_set (rtx
, struct epi_info
*);
4744 static void update_epilogue_consts (rtx
, rtx
, void *);
4745 static void emit_equiv_load (struct epi_info
*);
4747 /* Modify INSN, a list of one or more insns that is part of the epilogue, to
4748 no modifications to the stack pointer. Return the new list of insns. */
4751 keep_stack_depressed (rtx insns
)
4754 struct epi_info info
;
4757 /* If the epilogue is just a single instruction, it must be OK as is. */
4758 if (NEXT_INSN (insns
) == NULL_RTX
)
4761 /* Otherwise, start a sequence, initialize the information we have, and
4762 process all the insns we were given. */
4765 info
.sp_equiv_reg
= stack_pointer_rtx
;
4767 info
.equiv_reg_src
= 0;
4769 for (j
= 0; j
< FIRST_PSEUDO_REGISTER
; j
++)
4770 info
.const_equiv
[j
] = 0;
4774 while (insn
!= NULL_RTX
)
4776 next
= NEXT_INSN (insn
);
4785 /* If this insn references the register that SP is equivalent to and
4786 we have a pending load to that register, we must force out the load
4787 first and then indicate we no longer know what SP's equivalent is. */
4788 if (info
.equiv_reg_src
!= 0
4789 && reg_referenced_p (info
.sp_equiv_reg
, PATTERN (insn
)))
4791 emit_equiv_load (&info
);
4792 info
.sp_equiv_reg
= 0;
4795 info
.new_sp_equiv_reg
= info
.sp_equiv_reg
;
4796 info
.new_sp_offset
= info
.sp_offset
;
4798 /* If this is a (RETURN) and the return address is on the stack,
4799 update the address and change to an indirect jump. */
4800 if (GET_CODE (PATTERN (insn
)) == RETURN
4801 || (GET_CODE (PATTERN (insn
)) == PARALLEL
4802 && GET_CODE (XVECEXP (PATTERN (insn
), 0, 0)) == RETURN
))
4804 rtx retaddr
= INCOMING_RETURN_ADDR_RTX
;
4806 HOST_WIDE_INT offset
= 0;
4807 rtx jump_insn
, jump_set
;
4809 /* If the return address is in a register, we can emit the insn
4810 unchanged. Otherwise, it must be a MEM and we see what the
4811 base register and offset are. In any case, we have to emit any
4812 pending load to the equivalent reg of SP, if any. */
4813 if (REG_P (retaddr
))
4815 emit_equiv_load (&info
);
4823 gcc_assert (MEM_P (retaddr
));
4825 ret_ptr
= XEXP (retaddr
, 0);
4827 if (REG_P (ret_ptr
))
4829 base
= gen_rtx_REG (Pmode
, REGNO (ret_ptr
));
4834 gcc_assert (GET_CODE (ret_ptr
) == PLUS
4835 && REG_P (XEXP (ret_ptr
, 0))
4836 && GET_CODE (XEXP (ret_ptr
, 1)) == CONST_INT
);
4837 base
= gen_rtx_REG (Pmode
, REGNO (XEXP (ret_ptr
, 0)));
4838 offset
= INTVAL (XEXP (ret_ptr
, 1));
4842 /* If the base of the location containing the return pointer
4843 is SP, we must update it with the replacement address. Otherwise,
4844 just build the necessary MEM. */
4845 retaddr
= plus_constant (base
, offset
);
4846 if (base
== stack_pointer_rtx
)
4847 retaddr
= simplify_replace_rtx (retaddr
, stack_pointer_rtx
,
4848 plus_constant (info
.sp_equiv_reg
,
4851 retaddr
= gen_rtx_MEM (Pmode
, retaddr
);
4852 MEM_NOTRAP_P (retaddr
) = 1;
4854 /* If there is a pending load to the equivalent register for SP
4855 and we reference that register, we must load our address into
4856 a scratch register and then do that load. */
4857 if (info
.equiv_reg_src
4858 && reg_overlap_mentioned_p (info
.equiv_reg_src
, retaddr
))
4863 for (regno
= 0; regno
< FIRST_PSEUDO_REGISTER
; regno
++)
4864 if (HARD_REGNO_MODE_OK (regno
, Pmode
)
4865 && !fixed_regs
[regno
]
4866 && TEST_HARD_REG_BIT (regs_invalidated_by_call
, regno
)
4868 (EXIT_BLOCK_PTR
->il
.rtl
->global_live_at_start
, regno
)
4869 && !refers_to_regno_p (regno
,
4870 regno
+ hard_regno_nregs
[regno
]
4872 info
.equiv_reg_src
, NULL
)
4873 && info
.const_equiv
[regno
] == 0)
4876 gcc_assert (regno
< FIRST_PSEUDO_REGISTER
);
4878 reg
= gen_rtx_REG (Pmode
, regno
);
4879 emit_move_insn (reg
, retaddr
);
4883 emit_equiv_load (&info
);
4884 jump_insn
= emit_jump_insn (gen_indirect_jump (retaddr
));
4886 /* Show the SET in the above insn is a RETURN. */
4887 jump_set
= single_set (jump_insn
);
4888 gcc_assert (jump_set
);
4889 SET_IS_RETURN_P (jump_set
) = 1;
4892 /* If SP is not mentioned in the pattern and its equivalent register, if
4893 any, is not modified, just emit it. Otherwise, if neither is set,
4894 replace the reference to SP and emit the insn. If none of those are
4895 true, handle each SET individually. */
4896 else if (!reg_mentioned_p (stack_pointer_rtx
, PATTERN (insn
))
4897 && (info
.sp_equiv_reg
== stack_pointer_rtx
4898 || !reg_set_p (info
.sp_equiv_reg
, insn
)))
4900 else if (! reg_set_p (stack_pointer_rtx
, insn
)
4901 && (info
.sp_equiv_reg
== stack_pointer_rtx
4902 || !reg_set_p (info
.sp_equiv_reg
, insn
)))
4906 changed
= validate_replace_rtx (stack_pointer_rtx
,
4907 plus_constant (info
.sp_equiv_reg
,
4910 gcc_assert (changed
);
4914 else if (GET_CODE (PATTERN (insn
)) == SET
)
4915 handle_epilogue_set (PATTERN (insn
), &info
);
4916 else if (GET_CODE (PATTERN (insn
)) == PARALLEL
)
4918 for (j
= 0; j
< XVECLEN (PATTERN (insn
), 0); j
++)
4919 if (GET_CODE (XVECEXP (PATTERN (insn
), 0, j
)) == SET
)
4920 handle_epilogue_set (XVECEXP (PATTERN (insn
), 0, j
), &info
);
4925 info
.sp_equiv_reg
= info
.new_sp_equiv_reg
;
4926 info
.sp_offset
= info
.new_sp_offset
;
4928 /* Now update any constants this insn sets. */
4929 note_stores (PATTERN (insn
), update_epilogue_consts
, &info
);
4933 insns
= get_insns ();
4938 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
4939 structure that contains information about what we've seen so far. We
4940 process this SET by either updating that data or by emitting one or
4944 handle_epilogue_set (rtx set
, struct epi_info
*p
)
4946 /* First handle the case where we are setting SP. Record what it is being
4947 set from, which we must be able to determine */
4948 if (reg_set_p (stack_pointer_rtx
, set
))
4950 gcc_assert (SET_DEST (set
) == stack_pointer_rtx
);
4952 if (GET_CODE (SET_SRC (set
)) == PLUS
)
4954 p
->new_sp_equiv_reg
= XEXP (SET_SRC (set
), 0);
4955 if (GET_CODE (XEXP (SET_SRC (set
), 1)) == CONST_INT
)
4956 p
->new_sp_offset
= INTVAL (XEXP (SET_SRC (set
), 1));
4959 gcc_assert (REG_P (XEXP (SET_SRC (set
), 1))
4960 && (REGNO (XEXP (SET_SRC (set
), 1))
4961 < FIRST_PSEUDO_REGISTER
)
4962 && p
->const_equiv
[REGNO (XEXP (SET_SRC (set
), 1))]);
4964 = INTVAL (p
->const_equiv
[REGNO (XEXP (SET_SRC (set
), 1))]);
4968 p
->new_sp_equiv_reg
= SET_SRC (set
), p
->new_sp_offset
= 0;
4970 /* If we are adjusting SP, we adjust from the old data. */
4971 if (p
->new_sp_equiv_reg
== stack_pointer_rtx
)
4973 p
->new_sp_equiv_reg
= p
->sp_equiv_reg
;
4974 p
->new_sp_offset
+= p
->sp_offset
;
4977 gcc_assert (p
->new_sp_equiv_reg
&& REG_P (p
->new_sp_equiv_reg
));
4982 /* Next handle the case where we are setting SP's equivalent
4983 register. We must not already have a value to set it to. We
4984 could update, but there seems little point in handling that case.
4985 Note that we have to allow for the case where we are setting the
4986 register set in the previous part of a PARALLEL inside a single
4987 insn. But use the old offset for any updates within this insn.
4988 We must allow for the case where the register is being set in a
4989 different (usually wider) mode than Pmode). */
4990 else if (p
->new_sp_equiv_reg
!= 0 && reg_set_p (p
->new_sp_equiv_reg
, set
))
4992 gcc_assert (!p
->equiv_reg_src
4993 && REG_P (p
->new_sp_equiv_reg
)
4994 && REG_P (SET_DEST (set
))
4995 && (GET_MODE_BITSIZE (GET_MODE (SET_DEST (set
)))
4997 && REGNO (p
->new_sp_equiv_reg
) == REGNO (SET_DEST (set
)));
4999 = simplify_replace_rtx (SET_SRC (set
), stack_pointer_rtx
,
5000 plus_constant (p
->sp_equiv_reg
,
5004 /* Otherwise, replace any references to SP in the insn to its new value
5005 and emit the insn. */
5008 SET_SRC (set
) = simplify_replace_rtx (SET_SRC (set
), stack_pointer_rtx
,
5009 plus_constant (p
->sp_equiv_reg
,
5011 SET_DEST (set
) = simplify_replace_rtx (SET_DEST (set
), stack_pointer_rtx
,
5012 plus_constant (p
->sp_equiv_reg
,
5018 /* Update the tracking information for registers set to constants. */
5021 update_epilogue_consts (rtx dest
, rtx x
, void *data
)
5023 struct epi_info
*p
= (struct epi_info
*) data
;
5026 if (!REG_P (dest
) || REGNO (dest
) >= FIRST_PSEUDO_REGISTER
)
5029 /* If we are either clobbering a register or doing a partial set,
5030 show we don't know the value. */
5031 else if (GET_CODE (x
) == CLOBBER
|| ! rtx_equal_p (dest
, SET_DEST (x
)))
5032 p
->const_equiv
[REGNO (dest
)] = 0;
5034 /* If we are setting it to a constant, record that constant. */
5035 else if (GET_CODE (SET_SRC (x
)) == CONST_INT
)
5036 p
->const_equiv
[REGNO (dest
)] = SET_SRC (x
);
5038 /* If this is a binary operation between a register we have been tracking
5039 and a constant, see if we can compute a new constant value. */
5040 else if (ARITHMETIC_P (SET_SRC (x
))
5041 && REG_P (XEXP (SET_SRC (x
), 0))
5042 && REGNO (XEXP (SET_SRC (x
), 0)) < FIRST_PSEUDO_REGISTER
5043 && p
->const_equiv
[REGNO (XEXP (SET_SRC (x
), 0))] != 0
5044 && GET_CODE (XEXP (SET_SRC (x
), 1)) == CONST_INT
5045 && 0 != (new = simplify_binary_operation
5046 (GET_CODE (SET_SRC (x
)), GET_MODE (dest
),
5047 p
->const_equiv
[REGNO (XEXP (SET_SRC (x
), 0))],
5048 XEXP (SET_SRC (x
), 1)))
5049 && GET_CODE (new) == CONST_INT
)
5050 p
->const_equiv
[REGNO (dest
)] = new;
5052 /* Otherwise, we can't do anything with this value. */
5054 p
->const_equiv
[REGNO (dest
)] = 0;
5057 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
5060 emit_equiv_load (struct epi_info
*p
)
5062 if (p
->equiv_reg_src
!= 0)
5064 rtx dest
= p
->sp_equiv_reg
;
5066 if (GET_MODE (p
->equiv_reg_src
) != GET_MODE (dest
))
5067 dest
= gen_rtx_REG (GET_MODE (p
->equiv_reg_src
),
5068 REGNO (p
->sp_equiv_reg
));
5070 emit_move_insn (dest
, p
->equiv_reg_src
);
5071 p
->equiv_reg_src
= 0;
5076 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
5077 this into place with notes indicating where the prologue ends and where
5078 the epilogue begins. Update the basic block information when possible. */
5081 thread_prologue_and_epilogue_insns (rtx f ATTRIBUTE_UNUSED
)
5085 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
5088 #ifdef HAVE_prologue
5089 rtx prologue_end
= NULL_RTX
;
5091 #if defined (HAVE_epilogue) || defined(HAVE_return)
5092 rtx epilogue_end
= NULL_RTX
;
5096 #ifdef HAVE_prologue
5100 seq
= gen_prologue ();
5103 /* Retain a map of the prologue insns. */
5104 record_insns (seq
, &prologue
);
5105 prologue_end
= emit_note (NOTE_INSN_PROLOGUE_END
);
5109 set_insn_locators (seq
, prologue_locator
);
5111 /* Can't deal with multiple successors of the entry block
5112 at the moment. Function should always have at least one
5114 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR
));
5116 insert_insn_on_edge (seq
, single_succ_edge (ENTRY_BLOCK_PTR
));
5121 /* If the exit block has no non-fake predecessors, we don't need
5123 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5124 if ((e
->flags
& EDGE_FAKE
) == 0)
5130 if (optimize
&& HAVE_return
)
5132 /* If we're allowed to generate a simple return instruction,
5133 then by definition we don't need a full epilogue. Examine
5134 the block that falls through to EXIT. If it does not
5135 contain any code, examine its predecessors and try to
5136 emit (conditional) return instructions. */
5141 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5142 if (e
->flags
& EDGE_FALLTHRU
)
5148 /* Verify that there are no active instructions in the last block. */
5149 label
= BB_END (last
);
5150 while (label
&& !LABEL_P (label
))
5152 if (active_insn_p (label
))
5154 label
= PREV_INSN (label
);
5157 if (BB_HEAD (last
) == label
&& LABEL_P (label
))
5160 rtx epilogue_line_note
= NULL_RTX
;
5162 /* Locate the line number associated with the closing brace,
5163 if we can find one. */
5164 for (seq
= get_last_insn ();
5165 seq
&& ! active_insn_p (seq
);
5166 seq
= PREV_INSN (seq
))
5167 if (NOTE_P (seq
) && NOTE_LINE_NUMBER (seq
) > 0)
5169 epilogue_line_note
= seq
;
5173 for (ei2
= ei_start (last
->preds
); (e
= ei_safe_edge (ei2
)); )
5175 basic_block bb
= e
->src
;
5178 if (bb
== ENTRY_BLOCK_PTR
)
5185 if (!JUMP_P (jump
) || JUMP_LABEL (jump
) != label
)
5191 /* If we have an unconditional jump, we can replace that
5192 with a simple return instruction. */
5193 if (simplejump_p (jump
))
5195 emit_return_into_block (bb
, epilogue_line_note
);
5199 /* If we have a conditional jump, we can try to replace
5200 that with a conditional return instruction. */
5201 else if (condjump_p (jump
))
5203 if (! redirect_jump (jump
, 0, 0))
5209 /* If this block has only one successor, it both jumps
5210 and falls through to the fallthru block, so we can't
5212 if (single_succ_p (bb
))
5224 /* Fix up the CFG for the successful change we just made. */
5225 redirect_edge_succ (e
, EXIT_BLOCK_PTR
);
5228 /* Emit a return insn for the exit fallthru block. Whether
5229 this is still reachable will be determined later. */
5231 emit_barrier_after (BB_END (last
));
5232 emit_return_into_block (last
, epilogue_line_note
);
5233 epilogue_end
= BB_END (last
);
5234 single_succ_edge (last
)->flags
&= ~EDGE_FALLTHRU
;
5239 /* Find the edge that falls through to EXIT. Other edges may exist
5240 due to RETURN instructions, but those don't need epilogues.
5241 There really shouldn't be a mixture -- either all should have
5242 been converted or none, however... */
5244 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5245 if (e
->flags
& EDGE_FALLTHRU
)
5250 #ifdef HAVE_epilogue
5254 epilogue_end
= emit_note (NOTE_INSN_EPILOGUE_BEG
);
5256 seq
= gen_epilogue ();
5258 #ifdef INCOMING_RETURN_ADDR_RTX
5259 /* If this function returns with the stack depressed and we can support
5260 it, massage the epilogue to actually do that. */
5261 if (TREE_CODE (TREE_TYPE (current_function_decl
)) == FUNCTION_TYPE
5262 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl
)))
5263 seq
= keep_stack_depressed (seq
);
5266 emit_jump_insn (seq
);
5268 /* Retain a map of the epilogue insns. */
5269 record_insns (seq
, &epilogue
);
5270 set_insn_locators (seq
, epilogue_locator
);
5275 insert_insn_on_edge (seq
, e
);
5283 if (! next_active_insn (BB_END (e
->src
)))
5285 /* We have a fall-through edge to the exit block, the source is not
5286 at the end of the function, and there will be an assembler epilogue
5287 at the end of the function.
5288 We can't use force_nonfallthru here, because that would try to
5289 use return. Inserting a jump 'by hand' is extremely messy, so
5290 we take advantage of cfg_layout_finalize using
5291 fixup_fallthru_exit_predecessor. */
5292 cfg_layout_initialize (0);
5293 FOR_EACH_BB (cur_bb
)
5294 if (cur_bb
->index
>= 0 && cur_bb
->next_bb
->index
>= 0)
5295 cur_bb
->aux
= cur_bb
->next_bb
;
5296 cfg_layout_finalize ();
5301 commit_edge_insertions ();
5303 #ifdef HAVE_sibcall_epilogue
5304 /* Emit sibling epilogues before any sibling call sites. */
5305 for (ei
= ei_start (EXIT_BLOCK_PTR
->preds
); (e
= ei_safe_edge (ei
)); )
5307 basic_block bb
= e
->src
;
5308 rtx insn
= BB_END (bb
);
5311 || ! SIBLING_CALL_P (insn
))
5318 emit_insn (gen_sibcall_epilogue ());
5322 /* Retain a map of the epilogue insns. Used in life analysis to
5323 avoid getting rid of sibcall epilogue insns. Do this before we
5324 actually emit the sequence. */
5325 record_insns (seq
, &sibcall_epilogue
);
5326 set_insn_locators (seq
, epilogue_locator
);
5328 emit_insn_before (seq
, insn
);
5333 #ifdef HAVE_prologue
5334 /* This is probably all useless now that we use locators. */
5339 /* GDB handles `break f' by setting a breakpoint on the first
5340 line note after the prologue. Which means (1) that if
5341 there are line number notes before where we inserted the
5342 prologue we should move them, and (2) we should generate a
5343 note before the end of the first basic block, if there isn't
5346 ??? This behavior is completely broken when dealing with
5347 multiple entry functions. We simply place the note always
5348 into first basic block and let alternate entry points
5352 for (insn
= prologue_end
; insn
; insn
= prev
)
5354 prev
= PREV_INSN (insn
);
5355 if (NOTE_P (insn
) && NOTE_LINE_NUMBER (insn
) > 0)
5357 /* Note that we cannot reorder the first insn in the
5358 chain, since rest_of_compilation relies on that
5359 remaining constant. */
5362 reorder_insns (insn
, insn
, prologue_end
);
5366 /* Find the last line number note in the first block. */
5367 for (insn
= BB_END (ENTRY_BLOCK_PTR
->next_bb
);
5368 insn
!= prologue_end
&& insn
;
5369 insn
= PREV_INSN (insn
))
5370 if (NOTE_P (insn
) && NOTE_LINE_NUMBER (insn
) > 0)
5373 /* If we didn't find one, make a copy of the first line number
5377 for (insn
= next_active_insn (prologue_end
);
5379 insn
= PREV_INSN (insn
))
5380 if (NOTE_P (insn
) && NOTE_LINE_NUMBER (insn
) > 0)
5382 emit_note_copy_after (insn
, prologue_end
);
5388 #ifdef HAVE_epilogue
5393 /* Similarly, move any line notes that appear after the epilogue.
5394 There is no need, however, to be quite so anal about the existence
5395 of such a note. Also move the NOTE_INSN_FUNCTION_END and (possibly)
5396 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
5398 for (insn
= epilogue_end
; insn
; insn
= next
)
5400 next
= NEXT_INSN (insn
);
5402 && (NOTE_LINE_NUMBER (insn
) > 0
5403 || NOTE_LINE_NUMBER (insn
) == NOTE_INSN_FUNCTION_BEG
5404 || NOTE_LINE_NUMBER (insn
) == NOTE_INSN_FUNCTION_END
))
5405 reorder_insns (insn
, insn
, PREV_INSN (epilogue_end
));
5411 /* Reposition the prologue-end and epilogue-begin notes after instruction
5412 scheduling and delayed branch scheduling. */
5415 reposition_prologue_and_epilogue_notes (rtx f ATTRIBUTE_UNUSED
)
5417 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
5418 rtx insn
, last
, note
;
5421 if ((len
= VEC_length (int, prologue
)) > 0)
5425 /* Scan from the beginning until we reach the last prologue insn.
5426 We apparently can't depend on basic_block_{head,end} after
5428 for (insn
= f
; insn
; insn
= NEXT_INSN (insn
))
5432 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_PROLOGUE_END
)
5435 else if (contains (insn
, &prologue
))
5445 /* Find the prologue-end note if we haven't already, and
5446 move it to just after the last prologue insn. */
5449 for (note
= last
; (note
= NEXT_INSN (note
));)
5451 && NOTE_LINE_NUMBER (note
) == NOTE_INSN_PROLOGUE_END
)
5455 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
5457 last
= NEXT_INSN (last
);
5458 reorder_insns (note
, note
, last
);
5462 if ((len
= VEC_length (int, epilogue
)) > 0)
5466 /* Scan from the end until we reach the first epilogue insn.
5467 We apparently can't depend on basic_block_{head,end} after
5469 for (insn
= get_last_insn (); insn
; insn
= PREV_INSN (insn
))
5473 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_EPILOGUE_BEG
)
5476 else if (contains (insn
, &epilogue
))
5486 /* Find the epilogue-begin note if we haven't already, and
5487 move it to just before the first epilogue insn. */
5490 for (note
= insn
; (note
= PREV_INSN (note
));)
5492 && NOTE_LINE_NUMBER (note
) == NOTE_INSN_EPILOGUE_BEG
)
5496 if (PREV_INSN (last
) != note
)
5497 reorder_insns (note
, note
, PREV_INSN (last
));
5500 #endif /* HAVE_prologue or HAVE_epilogue */
5503 /* Resets insn_block_boundaries array. */
5506 reset_block_changes (void)
5508 VARRAY_TREE_INIT (cfun
->ib_boundaries_block
, 100, "ib_boundaries_block");
5509 VARRAY_PUSH_TREE (cfun
->ib_boundaries_block
, NULL_TREE
);
5512 /* Record the boundary for BLOCK. */
5514 record_block_change (tree block
)
5522 if(!cfun
->ib_boundaries_block
)
5525 last_block
= VARRAY_TOP_TREE (cfun
->ib_boundaries_block
);
5526 VARRAY_POP (cfun
->ib_boundaries_block
);
5528 for (i
= VARRAY_ACTIVE_SIZE (cfun
->ib_boundaries_block
); i
< n
; i
++)
5529 VARRAY_PUSH_TREE (cfun
->ib_boundaries_block
, last_block
);
5531 VARRAY_PUSH_TREE (cfun
->ib_boundaries_block
, block
);
5534 /* Finishes record of boundaries. */
5535 void finalize_block_changes (void)
5537 record_block_change (DECL_INITIAL (current_function_decl
));
5540 /* For INSN return the BLOCK it belongs to. */
5542 check_block_change (rtx insn
, tree
*block
)
5544 unsigned uid
= INSN_UID (insn
);
5546 if (uid
>= VARRAY_ACTIVE_SIZE (cfun
->ib_boundaries_block
))
5549 *block
= VARRAY_TREE (cfun
->ib_boundaries_block
, uid
);
5552 /* Releases the ib_boundaries_block records. */
5554 free_block_changes (void)
5556 cfun
->ib_boundaries_block
= NULL
;
5559 /* Returns the name of the current function. */
5561 current_function_name (void)
5563 return lang_hooks
.decl_printable_name (cfun
->decl
, 2);
5568 rest_of_handle_check_leaf_regs (void)
5570 #ifdef LEAF_REGISTERS
5571 current_function_uses_only_leaf_regs
5572 = optimize
> 0 && only_leaf_regs_used () && leaf_function_p ();
5576 struct tree_opt_pass pass_leaf_regs
=
5580 rest_of_handle_check_leaf_regs
, /* execute */
5583 0, /* static_pass_number */
5585 0, /* properties_required */
5586 0, /* properties_provided */
5587 0, /* properties_destroyed */
5588 0, /* todo_flags_start */
5589 0, /* todo_flags_finish */
5594 #include "gt-function.h"