1 /* Expands front end tree to back end RTL for GCC.
2 Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007
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"
68 #ifndef LOCAL_ALIGNMENT
69 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
72 #ifndef STACK_ALIGNMENT_NEEDED
73 #define STACK_ALIGNMENT_NEEDED 1
76 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
78 /* Some systems use __main in a way incompatible with its use in gcc, in these
79 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
80 give the same symbol without quotes for an alternative entry point. You
81 must define both, or neither. */
83 #define NAME__MAIN "__main"
86 /* Round a value to the lowest integer less than it that is a multiple of
87 the required alignment. Avoid using division in case the value is
88 negative. Assume the alignment is a power of two. */
89 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
91 /* Similar, but round to the next highest integer that meets the
93 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
95 /* Nonzero if function being compiled doesn't contain any calls
96 (ignoring the prologue and epilogue). This is set prior to
97 local register allocation and is valid for the remaining
99 int current_function_is_leaf
;
101 /* Nonzero if function being compiled doesn't modify the stack pointer
102 (ignoring the prologue and epilogue). This is only valid after
103 life_analysis has run. */
104 int current_function_sp_is_unchanging
;
106 /* Nonzero if the function being compiled is a leaf function which only
107 uses leaf registers. This is valid after reload (specifically after
108 sched2) and is useful only if the port defines LEAF_REGISTERS. */
109 int current_function_uses_only_leaf_regs
;
111 /* Nonzero once virtual register instantiation has been done.
112 assign_stack_local uses frame_pointer_rtx when this is nonzero.
113 calls.c:emit_library_call_value_1 uses it to set up
114 post-instantiation libcalls. */
115 int virtuals_instantiated
;
117 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
118 static GTY(()) int funcdef_no
;
120 /* These variables hold pointers to functions to create and destroy
121 target specific, per-function data structures. */
122 struct machine_function
* (*init_machine_status
) (void);
124 /* The currently compiled function. */
125 struct function
*cfun
= 0;
127 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
128 static VEC(int,heap
) *prologue
;
129 static VEC(int,heap
) *epilogue
;
131 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
133 static VEC(int,heap
) *sibcall_epilogue
;
135 /* In order to evaluate some expressions, such as function calls returning
136 structures in memory, we need to temporarily allocate stack locations.
137 We record each allocated temporary in the following structure.
139 Associated with each temporary slot is a nesting level. When we pop up
140 one level, all temporaries associated with the previous level are freed.
141 Normally, all temporaries are freed after the execution of the statement
142 in which they were created. However, if we are inside a ({...}) grouping,
143 the result may be in a temporary and hence must be preserved. If the
144 result could be in a temporary, we preserve it if we can determine which
145 one it is in. If we cannot determine which temporary may contain the
146 result, all temporaries are preserved. A temporary is preserved by
147 pretending it was allocated at the previous nesting level.
149 Automatic variables are also assigned temporary slots, at the nesting
150 level where they are defined. They are marked a "kept" so that
151 free_temp_slots will not free them. */
153 struct temp_slot
GTY(())
155 /* Points to next temporary slot. */
156 struct temp_slot
*next
;
157 /* Points to previous temporary slot. */
158 struct temp_slot
*prev
;
160 /* The rtx to used to reference the slot. */
162 /* The rtx used to represent the address if not the address of the
163 slot above. May be an EXPR_LIST if multiple addresses exist. */
165 /* The alignment (in bits) of the slot. */
167 /* The size, in units, of the slot. */
169 /* The type of the object in the slot, or zero if it doesn't correspond
170 to a type. We use this to determine whether a slot can be reused.
171 It can be reused if objects of the type of the new slot will always
172 conflict with objects of the type of the old slot. */
174 /* Nonzero if this temporary is currently in use. */
176 /* Nonzero if this temporary has its address taken. */
178 /* Nesting level at which this slot is being used. */
180 /* Nonzero if this should survive a call to free_temp_slots. */
182 /* The offset of the slot from the frame_pointer, including extra space
183 for alignment. This info is for combine_temp_slots. */
184 HOST_WIDE_INT base_offset
;
185 /* The size of the slot, including extra space for alignment. This
186 info is for combine_temp_slots. */
187 HOST_WIDE_INT full_size
;
190 /* Forward declarations. */
192 static rtx
assign_stack_local_1 (enum machine_mode
, HOST_WIDE_INT
, int,
194 static struct temp_slot
*find_temp_slot_from_address (rtx
);
195 static void pad_to_arg_alignment (struct args_size
*, int, struct args_size
*);
196 static void pad_below (struct args_size
*, enum machine_mode
, tree
);
197 static void reorder_blocks_1 (rtx
, tree
, VEC(tree
,heap
) **);
198 static int all_blocks (tree
, tree
*);
199 static tree
*get_block_vector (tree
, int *);
200 extern tree
debug_find_var_in_block_tree (tree
, tree
);
201 /* We always define `record_insns' even if it's not used so that we
202 can always export `prologue_epilogue_contains'. */
203 static void record_insns (rtx
, VEC(int,heap
) **) ATTRIBUTE_UNUSED
;
204 static int contains (rtx
, VEC(int,heap
) **);
206 static void emit_return_into_block (basic_block
);
208 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
209 static rtx
keep_stack_depressed (rtx
);
211 static void prepare_function_start (tree
);
212 static void do_clobber_return_reg (rtx
, void *);
213 static void do_use_return_reg (rtx
, void *);
214 static void set_insn_locators (rtx
, int) ATTRIBUTE_UNUSED
;
216 /* Pointer to chain of `struct function' for containing functions. */
217 struct function
*outer_function_chain
;
219 /* Given a function decl for a containing function,
220 return the `struct function' for it. */
223 find_function_data (tree decl
)
227 for (p
= outer_function_chain
; p
; p
= p
->outer
)
234 /* Save the current context for compilation of a nested function.
235 This is called from language-specific code. The caller should use
236 the enter_nested langhook to save any language-specific state,
237 since this function knows only about language-independent
241 push_function_context_to (tree context ATTRIBUTE_UNUSED
)
246 init_dummy_function_start ();
249 p
->outer
= outer_function_chain
;
250 outer_function_chain
= p
;
252 lang_hooks
.function
.enter_nested (p
);
258 push_function_context (void)
260 push_function_context_to (current_function_decl
);
263 /* Restore the last saved context, at the end of a nested function.
264 This function is called from language-specific code. */
267 pop_function_context_from (tree context ATTRIBUTE_UNUSED
)
269 struct function
*p
= outer_function_chain
;
272 outer_function_chain
= p
->outer
;
274 current_function_decl
= p
->decl
;
276 lang_hooks
.function
.leave_nested (p
);
278 /* Reset variables that have known state during rtx generation. */
279 virtuals_instantiated
= 0;
280 generating_concat_p
= 1;
284 pop_function_context (void)
286 pop_function_context_from (current_function_decl
);
289 /* Clear out all parts of the state in F that can safely be discarded
290 after the function has been parsed, but not compiled, to let
291 garbage collection reclaim the memory. */
294 free_after_parsing (struct function
*f
)
296 /* f->expr->forced_labels is used by code generation. */
297 /* f->emit->regno_reg_rtx is used by code generation. */
298 /* f->varasm is used by code generation. */
299 /* f->eh->eh_return_stub_label is used by code generation. */
301 lang_hooks
.function
.final (f
);
304 /* Clear out all parts of the state in F that can safely be discarded
305 after the function has been compiled, to let garbage collection
306 reclaim the memory. */
309 free_after_compilation (struct function
*f
)
311 VEC_free (int, heap
, prologue
);
312 VEC_free (int, heap
, epilogue
);
313 VEC_free (int, heap
, sibcall_epilogue
);
322 f
->x_avail_temp_slots
= NULL
;
323 f
->x_used_temp_slots
= NULL
;
324 f
->arg_offset_rtx
= NULL
;
325 f
->return_rtx
= NULL
;
326 f
->internal_arg_pointer
= NULL
;
327 f
->x_nonlocal_goto_handler_labels
= NULL
;
328 f
->x_return_label
= NULL
;
329 f
->x_naked_return_label
= NULL
;
330 f
->x_stack_slot_list
= NULL
;
331 f
->x_stack_check_probe_note
= NULL
;
332 f
->x_arg_pointer_save_area
= NULL
;
333 f
->x_parm_birth_insn
= NULL
;
334 f
->epilogue_delay_list
= NULL
;
337 /* Allocate fixed slots in the stack frame of the current function. */
339 /* Return size needed for stack frame based on slots so far allocated in
341 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
342 the caller may have to do that. */
345 get_func_frame_size (struct function
*f
)
347 if (FRAME_GROWS_DOWNWARD
)
348 return -f
->x_frame_offset
;
350 return f
->x_frame_offset
;
353 /* Return size needed for stack frame based on slots so far allocated.
354 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
355 the caller may have to do that. */
358 get_frame_size (void)
360 return get_func_frame_size (cfun
);
363 /* Issue an error message and return TRUE if frame OFFSET overflows in
364 the signed target pointer arithmetics for function FUNC. Otherwise
368 frame_offset_overflow (HOST_WIDE_INT offset
, tree func
)
370 unsigned HOST_WIDE_INT size
= FRAME_GROWS_DOWNWARD
? -offset
: offset
;
372 if (size
> ((unsigned HOST_WIDE_INT
) 1 << (GET_MODE_BITSIZE (Pmode
) - 1))
373 /* Leave room for the fixed part of the frame. */
374 - 64 * UNITS_PER_WORD
)
376 error ("%Jtotal size of local objects too large", func
);
383 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
384 with machine mode MODE.
386 ALIGN controls the amount of alignment for the address of the slot:
387 0 means according to MODE,
388 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
389 -2 means use BITS_PER_UNIT,
390 positive specifies alignment boundary in bits.
392 We do not round to stack_boundary here.
394 FUNCTION specifies the function to allocate in. */
397 assign_stack_local_1 (enum machine_mode mode
, HOST_WIDE_INT size
, int align
,
398 struct function
*function
)
401 int bigend_correction
= 0;
402 unsigned int alignment
;
403 int frame_off
, frame_alignment
, frame_phase
;
410 alignment
= BIGGEST_ALIGNMENT
;
412 alignment
= GET_MODE_ALIGNMENT (mode
);
414 /* Allow the target to (possibly) increase the alignment of this
416 type
= lang_hooks
.types
.type_for_mode (mode
, 0);
418 alignment
= LOCAL_ALIGNMENT (type
, alignment
);
420 alignment
/= BITS_PER_UNIT
;
422 else if (align
== -1)
424 alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
425 size
= CEIL_ROUND (size
, alignment
);
427 else if (align
== -2)
428 alignment
= 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
430 alignment
= align
/ BITS_PER_UNIT
;
432 if (FRAME_GROWS_DOWNWARD
)
433 function
->x_frame_offset
-= size
;
435 /* Ignore alignment we can't do with expected alignment of the boundary. */
436 if (alignment
* BITS_PER_UNIT
> PREFERRED_STACK_BOUNDARY
)
437 alignment
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
439 if (function
->stack_alignment_needed
< alignment
* BITS_PER_UNIT
)
440 function
->stack_alignment_needed
= alignment
* BITS_PER_UNIT
;
442 /* Calculate how many bytes the start of local variables is off from
444 frame_alignment
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
445 frame_off
= STARTING_FRAME_OFFSET
% frame_alignment
;
446 frame_phase
= frame_off
? frame_alignment
- frame_off
: 0;
448 /* Round the frame offset to the specified alignment. The default is
449 to always honor requests to align the stack but a port may choose to
450 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
451 if (STACK_ALIGNMENT_NEEDED
455 /* We must be careful here, since FRAME_OFFSET might be negative and
456 division with a negative dividend isn't as well defined as we might
457 like. So we instead assume that ALIGNMENT is a power of two and
458 use logical operations which are unambiguous. */
459 if (FRAME_GROWS_DOWNWARD
)
460 function
->x_frame_offset
461 = (FLOOR_ROUND (function
->x_frame_offset
- frame_phase
,
462 (unsigned HOST_WIDE_INT
) alignment
)
465 function
->x_frame_offset
466 = (CEIL_ROUND (function
->x_frame_offset
- frame_phase
,
467 (unsigned HOST_WIDE_INT
) alignment
)
471 /* On a big-endian machine, if we are allocating more space than we will use,
472 use the least significant bytes of those that are allocated. */
473 if (BYTES_BIG_ENDIAN
&& mode
!= BLKmode
&& GET_MODE_SIZE (mode
) < size
)
474 bigend_correction
= size
- GET_MODE_SIZE (mode
);
476 /* If we have already instantiated virtual registers, return the actual
477 address relative to the frame pointer. */
478 if (function
== cfun
&& virtuals_instantiated
)
479 addr
= plus_constant (frame_pointer_rtx
,
481 (frame_offset
+ bigend_correction
482 + STARTING_FRAME_OFFSET
, Pmode
));
484 addr
= plus_constant (virtual_stack_vars_rtx
,
486 (function
->x_frame_offset
+ bigend_correction
,
489 if (!FRAME_GROWS_DOWNWARD
)
490 function
->x_frame_offset
+= size
;
492 x
= gen_rtx_MEM (mode
, addr
);
493 MEM_NOTRAP_P (x
) = 1;
495 function
->x_stack_slot_list
496 = gen_rtx_EXPR_LIST (VOIDmode
, x
, function
->x_stack_slot_list
);
498 if (frame_offset_overflow (function
->x_frame_offset
, function
->decl
))
499 function
->x_frame_offset
= 0;
504 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
508 assign_stack_local (enum machine_mode mode
, HOST_WIDE_INT size
, int align
)
510 return assign_stack_local_1 (mode
, size
, align
, cfun
);
514 /* Removes temporary slot TEMP from LIST. */
517 cut_slot_from_list (struct temp_slot
*temp
, struct temp_slot
**list
)
520 temp
->next
->prev
= temp
->prev
;
522 temp
->prev
->next
= temp
->next
;
526 temp
->prev
= temp
->next
= NULL
;
529 /* Inserts temporary slot TEMP to LIST. */
532 insert_slot_to_list (struct temp_slot
*temp
, struct temp_slot
**list
)
536 (*list
)->prev
= temp
;
541 /* Returns the list of used temp slots at LEVEL. */
543 static struct temp_slot
**
544 temp_slots_at_level (int level
)
546 if (level
>= (int) VEC_length (temp_slot_p
, used_temp_slots
))
547 VEC_safe_grow_cleared (temp_slot_p
, gc
, used_temp_slots
, level
+ 1);
549 return &(VEC_address (temp_slot_p
, used_temp_slots
)[level
]);
552 /* Returns the maximal temporary slot level. */
555 max_slot_level (void)
557 if (!used_temp_slots
)
560 return VEC_length (temp_slot_p
, 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.
630 If assign_stack_temp is called outside of the tree->rtl expansion,
631 we cannot reuse the stack slots (that may still refer to
632 VIRTUAL_STACK_VARS_REGNUM). */
633 if (!virtuals_instantiated
)
635 for (p
= avail_temp_slots
; p
; p
= p
->next
)
637 if (p
->align
>= align
&& p
->size
>= size
638 && GET_MODE (p
->slot
) == mode
639 && objects_must_conflict_p (p
->type
, type
)
640 && (best_p
== 0 || best_p
->size
> p
->size
641 || (best_p
->size
== p
->size
&& best_p
->align
> p
->align
)))
643 if (p
->align
== align
&& p
->size
== size
)
646 cut_slot_from_list (selected
, &avail_temp_slots
);
655 /* Make our best, if any, the one to use. */
659 cut_slot_from_list (selected
, &avail_temp_slots
);
661 /* If there are enough aligned bytes left over, make them into a new
662 temp_slot so that the extra bytes don't get wasted. Do this only
663 for BLKmode slots, so that we can be sure of the alignment. */
664 if (GET_MODE (best_p
->slot
) == BLKmode
)
666 int alignment
= best_p
->align
/ BITS_PER_UNIT
;
667 HOST_WIDE_INT rounded_size
= CEIL_ROUND (size
, alignment
);
669 if (best_p
->size
- rounded_size
>= alignment
)
671 p
= ggc_alloc (sizeof (struct temp_slot
));
672 p
->in_use
= p
->addr_taken
= 0;
673 p
->size
= best_p
->size
- rounded_size
;
674 p
->base_offset
= best_p
->base_offset
+ rounded_size
;
675 p
->full_size
= best_p
->full_size
- rounded_size
;
676 p
->slot
= adjust_address_nv (best_p
->slot
, BLKmode
, rounded_size
);
677 p
->align
= best_p
->align
;
679 p
->type
= best_p
->type
;
680 insert_slot_to_list (p
, &avail_temp_slots
);
682 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, p
->slot
,
685 best_p
->size
= rounded_size
;
686 best_p
->full_size
= rounded_size
;
691 /* If we still didn't find one, make a new temporary. */
694 HOST_WIDE_INT frame_offset_old
= frame_offset
;
696 p
= ggc_alloc (sizeof (struct temp_slot
));
698 /* We are passing an explicit alignment request to assign_stack_local.
699 One side effect of that is assign_stack_local will not round SIZE
700 to ensure the frame offset remains suitably aligned.
702 So for requests which depended on the rounding of SIZE, we go ahead
703 and round it now. We also make sure ALIGNMENT is at least
704 BIGGEST_ALIGNMENT. */
705 gcc_assert (mode
!= BLKmode
|| align
== BIGGEST_ALIGNMENT
);
706 p
->slot
= assign_stack_local (mode
,
708 ? CEIL_ROUND (size
, (int) align
/ BITS_PER_UNIT
)
714 /* The following slot size computation is necessary because we don't
715 know the actual size of the temporary slot until assign_stack_local
716 has performed all the frame alignment and size rounding for the
717 requested temporary. Note that extra space added for alignment
718 can be either above or below this stack slot depending on which
719 way the frame grows. We include the extra space if and only if it
720 is above this slot. */
721 if (FRAME_GROWS_DOWNWARD
)
722 p
->size
= frame_offset_old
- frame_offset
;
726 /* Now define the fields used by combine_temp_slots. */
727 if (FRAME_GROWS_DOWNWARD
)
729 p
->base_offset
= frame_offset
;
730 p
->full_size
= frame_offset_old
- frame_offset
;
734 p
->base_offset
= frame_offset_old
;
735 p
->full_size
= frame_offset
- frame_offset_old
;
746 p
->level
= temp_slot_level
;
749 pp
= temp_slots_at_level (p
->level
);
750 insert_slot_to_list (p
, pp
);
752 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
753 slot
= gen_rtx_MEM (mode
, XEXP (p
->slot
, 0));
754 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, slot
, stack_slot_list
);
756 /* If we know the alias set for the memory that will be used, use
757 it. If there's no TYPE, then we don't know anything about the
758 alias set for the memory. */
759 set_mem_alias_set (slot
, type
? get_alias_set (type
) : 0);
760 set_mem_align (slot
, align
);
762 /* If a type is specified, set the relevant flags. */
765 MEM_VOLATILE_P (slot
) = TYPE_VOLATILE (type
);
766 MEM_SET_IN_STRUCT_P (slot
, AGGREGATE_TYPE_P (type
));
768 MEM_NOTRAP_P (slot
) = 1;
773 /* Allocate a temporary stack slot and record it for possible later
774 reuse. First three arguments are same as in preceding function. */
777 assign_stack_temp (enum machine_mode mode
, HOST_WIDE_INT size
, int keep
)
779 return assign_stack_temp_for_type (mode
, size
, keep
, NULL_TREE
);
782 /* Assign a temporary.
783 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
784 and so that should be used in error messages. In either case, we
785 allocate of the given type.
786 KEEP is as for assign_stack_temp.
787 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
788 it is 0 if a register is OK.
789 DONT_PROMOTE is 1 if we should not promote values in register
793 assign_temp (tree type_or_decl
, int keep
, int memory_required
,
794 int dont_promote ATTRIBUTE_UNUSED
)
797 enum machine_mode mode
;
802 if (DECL_P (type_or_decl
))
803 decl
= type_or_decl
, type
= TREE_TYPE (decl
);
805 decl
= NULL
, type
= type_or_decl
;
807 mode
= TYPE_MODE (type
);
809 unsignedp
= TYPE_UNSIGNED (type
);
812 if (mode
== BLKmode
|| memory_required
)
814 HOST_WIDE_INT size
= int_size_in_bytes (type
);
817 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
818 problems with allocating the stack space. */
822 /* Unfortunately, we don't yet know how to allocate variable-sized
823 temporaries. However, sometimes we can find a fixed upper limit on
824 the size, so try that instead. */
826 size
= max_int_size_in_bytes (type
);
828 /* The size of the temporary may be too large to fit into an integer. */
829 /* ??? Not sure this should happen except for user silliness, so limit
830 this to things that aren't compiler-generated temporaries. The
831 rest of the time we'll die in assign_stack_temp_for_type. */
832 if (decl
&& size
== -1
833 && TREE_CODE (TYPE_SIZE_UNIT (type
)) == INTEGER_CST
)
835 error ("size of variable %q+D is too large", decl
);
839 tmp
= assign_stack_temp_for_type (mode
, size
, keep
, type
);
845 mode
= promote_mode (type
, mode
, &unsignedp
, 0);
848 return gen_reg_rtx (mode
);
851 /* Combine temporary stack slots which are adjacent on the stack.
853 This allows for better use of already allocated stack space. This is only
854 done for BLKmode slots because we can be sure that we won't have alignment
855 problems in this case. */
858 combine_temp_slots (void)
860 struct temp_slot
*p
, *q
, *next
, *next_q
;
863 /* We can't combine slots, because the information about which slot
864 is in which alias set will be lost. */
865 if (flag_strict_aliasing
)
868 /* If there are a lot of temp slots, don't do anything unless
869 high levels of optimization. */
870 if (! flag_expensive_optimizations
)
871 for (p
= avail_temp_slots
, num_slots
= 0; p
; p
= p
->next
, num_slots
++)
872 if (num_slots
> 100 || (num_slots
> 10 && optimize
== 0))
875 for (p
= avail_temp_slots
; p
; p
= next
)
881 if (GET_MODE (p
->slot
) != BLKmode
)
884 for (q
= p
->next
; q
; q
= next_q
)
890 if (GET_MODE (q
->slot
) != BLKmode
)
893 if (p
->base_offset
+ p
->full_size
== q
->base_offset
)
895 /* Q comes after P; combine Q into P. */
897 p
->full_size
+= q
->full_size
;
900 else if (q
->base_offset
+ q
->full_size
== p
->base_offset
)
902 /* P comes after Q; combine P into Q. */
904 q
->full_size
+= p
->full_size
;
909 cut_slot_from_list (q
, &avail_temp_slots
);
912 /* Either delete P or advance past it. */
914 cut_slot_from_list (p
, &avail_temp_slots
);
918 /* Find the temp slot corresponding to the object at address X. */
920 static struct temp_slot
*
921 find_temp_slot_from_address (rtx x
)
927 for (i
= max_slot_level (); i
>= 0; i
--)
928 for (p
= *temp_slots_at_level (i
); p
; p
= p
->next
)
930 if (XEXP (p
->slot
, 0) == x
932 || (GET_CODE (x
) == PLUS
933 && XEXP (x
, 0) == virtual_stack_vars_rtx
934 && GET_CODE (XEXP (x
, 1)) == CONST_INT
935 && INTVAL (XEXP (x
, 1)) >= p
->base_offset
936 && INTVAL (XEXP (x
, 1)) < p
->base_offset
+ p
->full_size
))
939 else if (p
->address
!= 0 && GET_CODE (p
->address
) == EXPR_LIST
)
940 for (next
= p
->address
; next
; next
= XEXP (next
, 1))
941 if (XEXP (next
, 0) == x
)
945 /* If we have a sum involving a register, see if it points to a temp
947 if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 0))
948 && (p
= find_temp_slot_from_address (XEXP (x
, 0))) != 0)
950 else if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 1))
951 && (p
= find_temp_slot_from_address (XEXP (x
, 1))) != 0)
957 /* Indicate that NEW is an alternate way of referring to the temp slot
958 that previously was known by OLD. */
961 update_temp_slot_address (rtx old
, rtx
new)
965 if (rtx_equal_p (old
, new))
968 p
= find_temp_slot_from_address (old
);
970 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
971 is a register, see if one operand of the PLUS is a temporary
972 location. If so, NEW points into it. Otherwise, if both OLD and
973 NEW are a PLUS and if there is a register in common between them.
974 If so, try a recursive call on those values. */
977 if (GET_CODE (old
) != PLUS
)
982 update_temp_slot_address (XEXP (old
, 0), new);
983 update_temp_slot_address (XEXP (old
, 1), new);
986 else if (GET_CODE (new) != PLUS
)
989 if (rtx_equal_p (XEXP (old
, 0), XEXP (new, 0)))
990 update_temp_slot_address (XEXP (old
, 1), XEXP (new, 1));
991 else if (rtx_equal_p (XEXP (old
, 1), XEXP (new, 0)))
992 update_temp_slot_address (XEXP (old
, 0), XEXP (new, 1));
993 else if (rtx_equal_p (XEXP (old
, 0), XEXP (new, 1)))
994 update_temp_slot_address (XEXP (old
, 1), XEXP (new, 0));
995 else if (rtx_equal_p (XEXP (old
, 1), XEXP (new, 1)))
996 update_temp_slot_address (XEXP (old
, 0), XEXP (new, 0));
1001 /* Otherwise add an alias for the temp's address. */
1002 else if (p
->address
== 0)
1006 if (GET_CODE (p
->address
) != EXPR_LIST
)
1007 p
->address
= gen_rtx_EXPR_LIST (VOIDmode
, p
->address
, NULL_RTX
);
1009 p
->address
= gen_rtx_EXPR_LIST (VOIDmode
, new, p
->address
);
1013 /* If X could be a reference to a temporary slot, mark the fact that its
1014 address was taken. */
1017 mark_temp_addr_taken (rtx x
)
1019 struct temp_slot
*p
;
1024 /* If X is not in memory or is at a constant address, it cannot be in
1025 a temporary slot. */
1026 if (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0)))
1029 p
= find_temp_slot_from_address (XEXP (x
, 0));
1034 /* If X could be a reference to a temporary slot, mark that slot as
1035 belonging to the to one level higher than the current level. If X
1036 matched one of our slots, just mark that one. Otherwise, we can't
1037 easily predict which it is, so upgrade all of them. Kept slots
1038 need not be touched.
1040 This is called when an ({...}) construct occurs and a statement
1041 returns a value in memory. */
1044 preserve_temp_slots (rtx x
)
1046 struct temp_slot
*p
= 0, *next
;
1048 /* If there is no result, we still might have some objects whose address
1049 were taken, so we need to make sure they stay around. */
1052 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1057 move_slot_to_level (p
, temp_slot_level
- 1);
1063 /* If X is a register that is being used as a pointer, see if we have
1064 a temporary slot we know it points to. To be consistent with
1065 the code below, we really should preserve all non-kept slots
1066 if we can't find a match, but that seems to be much too costly. */
1067 if (REG_P (x
) && REG_POINTER (x
))
1068 p
= find_temp_slot_from_address (x
);
1070 /* If X is not in memory or is at a constant address, it cannot be in
1071 a temporary slot, but it can contain something whose address was
1073 if (p
== 0 && (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0))))
1075 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1080 move_slot_to_level (p
, temp_slot_level
- 1);
1086 /* First see if we can find a match. */
1088 p
= find_temp_slot_from_address (XEXP (x
, 0));
1092 /* Move everything at our level whose address was taken to our new
1093 level in case we used its address. */
1094 struct temp_slot
*q
;
1096 if (p
->level
== temp_slot_level
)
1098 for (q
= *temp_slots_at_level (temp_slot_level
); q
; q
= next
)
1102 if (p
!= q
&& q
->addr_taken
)
1103 move_slot_to_level (q
, temp_slot_level
- 1);
1106 move_slot_to_level (p
, temp_slot_level
- 1);
1112 /* Otherwise, preserve all non-kept slots at this level. */
1113 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1118 move_slot_to_level (p
, temp_slot_level
- 1);
1122 /* Free all temporaries used so far. This is normally called at the
1123 end of generating code for a statement. */
1126 free_temp_slots (void)
1128 struct temp_slot
*p
, *next
;
1130 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1135 make_slot_available (p
);
1138 combine_temp_slots ();
1141 /* Push deeper into the nesting level for stack temporaries. */
1144 push_temp_slots (void)
1149 /* Pop a temporary nesting level. All slots in use in the current level
1153 pop_temp_slots (void)
1155 struct temp_slot
*p
, *next
;
1157 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1160 make_slot_available (p
);
1163 combine_temp_slots ();
1168 /* Initialize temporary slots. */
1171 init_temp_slots (void)
1173 /* We have not allocated any temporaries yet. */
1174 avail_temp_slots
= 0;
1175 used_temp_slots
= 0;
1176 temp_slot_level
= 0;
1179 /* These routines are responsible for converting virtual register references
1180 to the actual hard register references once RTL generation is complete.
1182 The following four variables are used for communication between the
1183 routines. They contain the offsets of the virtual registers from their
1184 respective hard registers. */
1186 static int in_arg_offset
;
1187 static int var_offset
;
1188 static int dynamic_offset
;
1189 static int out_arg_offset
;
1190 static int cfa_offset
;
1192 /* In most machines, the stack pointer register is equivalent to the bottom
1195 #ifndef STACK_POINTER_OFFSET
1196 #define STACK_POINTER_OFFSET 0
1199 /* If not defined, pick an appropriate default for the offset of dynamically
1200 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1201 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1203 #ifndef STACK_DYNAMIC_OFFSET
1205 /* The bottom of the stack points to the actual arguments. If
1206 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1207 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1208 stack space for register parameters is not pushed by the caller, but
1209 rather part of the fixed stack areas and hence not included in
1210 `current_function_outgoing_args_size'. Nevertheless, we must allow
1211 for it when allocating stack dynamic objects. */
1213 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
1214 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1215 ((ACCUMULATE_OUTGOING_ARGS \
1216 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
1217 + (STACK_POINTER_OFFSET)) \
1220 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1221 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
1222 + (STACK_POINTER_OFFSET))
1227 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1228 is a virtual register, return the equivalent hard register and set the
1229 offset indirectly through the pointer. Otherwise, return 0. */
1232 instantiate_new_reg (rtx x
, HOST_WIDE_INT
*poffset
)
1235 HOST_WIDE_INT offset
;
1237 if (x
== virtual_incoming_args_rtx
)
1238 new = arg_pointer_rtx
, offset
= in_arg_offset
;
1239 else if (x
== virtual_stack_vars_rtx
)
1240 new = frame_pointer_rtx
, offset
= var_offset
;
1241 else if (x
== virtual_stack_dynamic_rtx
)
1242 new = stack_pointer_rtx
, offset
= dynamic_offset
;
1243 else if (x
== virtual_outgoing_args_rtx
)
1244 new = stack_pointer_rtx
, offset
= out_arg_offset
;
1245 else if (x
== virtual_cfa_rtx
)
1247 #ifdef FRAME_POINTER_CFA_OFFSET
1248 new = frame_pointer_rtx
;
1250 new = arg_pointer_rtx
;
1252 offset
= cfa_offset
;
1261 /* A subroutine of instantiate_virtual_regs, called via for_each_rtx.
1262 Instantiate any virtual registers present inside of *LOC. The expression
1263 is simplified, as much as possible, but is not to be considered "valid"
1264 in any sense implied by the target. If any change is made, set CHANGED
1268 instantiate_virtual_regs_in_rtx (rtx
*loc
, void *data
)
1270 HOST_WIDE_INT offset
;
1271 bool *changed
= (bool *) data
;
1278 switch (GET_CODE (x
))
1281 new = instantiate_new_reg (x
, &offset
);
1284 *loc
= plus_constant (new, offset
);
1291 new = instantiate_new_reg (XEXP (x
, 0), &offset
);
1294 new = plus_constant (new, offset
);
1295 *loc
= simplify_gen_binary (PLUS
, GET_MODE (x
), new, XEXP (x
, 1));
1301 /* FIXME -- from old code */
1302 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1303 we can commute the PLUS and SUBREG because pointers into the
1304 frame are well-behaved. */
1314 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1315 matches the predicate for insn CODE operand OPERAND. */
1318 safe_insn_predicate (int code
, int operand
, rtx x
)
1320 const struct insn_operand_data
*op_data
;
1325 op_data
= &insn_data
[code
].operand
[operand
];
1326 if (op_data
->predicate
== NULL
)
1329 return op_data
->predicate (x
, op_data
->mode
);
1332 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1333 registers present inside of insn. The result will be a valid insn. */
1336 instantiate_virtual_regs_in_insn (rtx insn
)
1338 HOST_WIDE_INT offset
;
1340 bool any_change
= false;
1341 rtx set
, new, x
, seq
;
1343 /* There are some special cases to be handled first. */
1344 set
= single_set (insn
);
1347 /* We're allowed to assign to a virtual register. This is interpreted
1348 to mean that the underlying register gets assigned the inverse
1349 transformation. This is used, for example, in the handling of
1351 new = instantiate_new_reg (SET_DEST (set
), &offset
);
1356 for_each_rtx (&SET_SRC (set
), instantiate_virtual_regs_in_rtx
, NULL
);
1357 x
= simplify_gen_binary (PLUS
, GET_MODE (new), SET_SRC (set
),
1359 x
= force_operand (x
, new);
1361 emit_move_insn (new, x
);
1366 emit_insn_before (seq
, insn
);
1371 /* Handle a straight copy from a virtual register by generating a
1372 new add insn. The difference between this and falling through
1373 to the generic case is avoiding a new pseudo and eliminating a
1374 move insn in the initial rtl stream. */
1375 new = instantiate_new_reg (SET_SRC (set
), &offset
);
1376 if (new && offset
!= 0
1377 && REG_P (SET_DEST (set
))
1378 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1382 x
= expand_simple_binop (GET_MODE (SET_DEST (set
)), PLUS
,
1383 new, GEN_INT (offset
), SET_DEST (set
),
1384 1, OPTAB_LIB_WIDEN
);
1385 if (x
!= SET_DEST (set
))
1386 emit_move_insn (SET_DEST (set
), x
);
1391 emit_insn_before (seq
, insn
);
1396 extract_insn (insn
);
1397 insn_code
= INSN_CODE (insn
);
1399 /* Handle a plus involving a virtual register by determining if the
1400 operands remain valid if they're modified in place. */
1401 if (GET_CODE (SET_SRC (set
)) == PLUS
1402 && recog_data
.n_operands
>= 3
1403 && recog_data
.operand_loc
[1] == &XEXP (SET_SRC (set
), 0)
1404 && recog_data
.operand_loc
[2] == &XEXP (SET_SRC (set
), 1)
1405 && GET_CODE (recog_data
.operand
[2]) == CONST_INT
1406 && (new = instantiate_new_reg (recog_data
.operand
[1], &offset
)))
1408 offset
+= INTVAL (recog_data
.operand
[2]);
1410 /* If the sum is zero, then replace with a plain move. */
1412 && REG_P (SET_DEST (set
))
1413 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1416 emit_move_insn (SET_DEST (set
), new);
1420 emit_insn_before (seq
, insn
);
1425 x
= gen_int_mode (offset
, recog_data
.operand_mode
[2]);
1427 /* Using validate_change and apply_change_group here leaves
1428 recog_data in an invalid state. Since we know exactly what
1429 we want to check, do those two by hand. */
1430 if (safe_insn_predicate (insn_code
, 1, new)
1431 && safe_insn_predicate (insn_code
, 2, x
))
1433 *recog_data
.operand_loc
[1] = recog_data
.operand
[1] = new;
1434 *recog_data
.operand_loc
[2] = recog_data
.operand
[2] = x
;
1437 /* Fall through into the regular operand fixup loop in
1438 order to take care of operands other than 1 and 2. */
1444 extract_insn (insn
);
1445 insn_code
= INSN_CODE (insn
);
1448 /* In the general case, we expect virtual registers to appear only in
1449 operands, and then only as either bare registers or inside memories. */
1450 for (i
= 0; i
< recog_data
.n_operands
; ++i
)
1452 x
= recog_data
.operand
[i
];
1453 switch (GET_CODE (x
))
1457 rtx addr
= XEXP (x
, 0);
1458 bool changed
= false;
1460 for_each_rtx (&addr
, instantiate_virtual_regs_in_rtx
, &changed
);
1465 x
= replace_equiv_address (x
, addr
);
1469 emit_insn_before (seq
, insn
);
1474 new = instantiate_new_reg (x
, &offset
);
1483 /* Careful, special mode predicates may have stuff in
1484 insn_data[insn_code].operand[i].mode that isn't useful
1485 to us for computing a new value. */
1486 /* ??? Recognize address_operand and/or "p" constraints
1487 to see if (plus new offset) is a valid before we put
1488 this through expand_simple_binop. */
1489 x
= expand_simple_binop (GET_MODE (x
), PLUS
, new,
1490 GEN_INT (offset
), NULL_RTX
,
1491 1, OPTAB_LIB_WIDEN
);
1494 emit_insn_before (seq
, insn
);
1499 new = instantiate_new_reg (SUBREG_REG (x
), &offset
);
1505 new = expand_simple_binop (GET_MODE (new), PLUS
, new,
1506 GEN_INT (offset
), NULL_RTX
,
1507 1, OPTAB_LIB_WIDEN
);
1510 emit_insn_before (seq
, insn
);
1512 x
= simplify_gen_subreg (recog_data
.operand_mode
[i
], new,
1513 GET_MODE (new), SUBREG_BYTE (x
));
1520 /* At this point, X contains the new value for the operand.
1521 Validate the new value vs the insn predicate. Note that
1522 asm insns will have insn_code -1 here. */
1523 if (!safe_insn_predicate (insn_code
, i
, x
))
1526 x
= force_reg (insn_data
[insn_code
].operand
[i
].mode
, x
);
1530 emit_insn_before (seq
, insn
);
1533 *recog_data
.operand_loc
[i
] = recog_data
.operand
[i
] = x
;
1539 /* Propagate operand changes into the duplicates. */
1540 for (i
= 0; i
< recog_data
.n_dups
; ++i
)
1541 *recog_data
.dup_loc
[i
]
1542 = copy_rtx (recog_data
.operand
[(unsigned)recog_data
.dup_num
[i
]]);
1544 /* Force re-recognition of the instruction for validation. */
1545 INSN_CODE (insn
) = -1;
1548 if (asm_noperands (PATTERN (insn
)) >= 0)
1550 if (!check_asm_operands (PATTERN (insn
)))
1552 error_for_asm (insn
, "impossible constraint in %<asm%>");
1558 if (recog_memoized (insn
) < 0)
1559 fatal_insn_not_found (insn
);
1563 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1564 do any instantiation required. */
1567 instantiate_decl (rtx x
)
1574 /* If this is a CONCAT, recurse for the pieces. */
1575 if (GET_CODE (x
) == CONCAT
)
1577 instantiate_decl (XEXP (x
, 0));
1578 instantiate_decl (XEXP (x
, 1));
1582 /* If this is not a MEM, no need to do anything. Similarly if the
1583 address is a constant or a register that is not a virtual register. */
1588 if (CONSTANT_P (addr
)
1590 && (REGNO (addr
) < FIRST_VIRTUAL_REGISTER
1591 || REGNO (addr
) > LAST_VIRTUAL_REGISTER
)))
1594 for_each_rtx (&XEXP (x
, 0), instantiate_virtual_regs_in_rtx
, NULL
);
1597 /* Helper for instantiate_decls called via walk_tree: Process all decls
1598 in the given DECL_VALUE_EXPR. */
1601 instantiate_expr (tree
*tp
, int *walk_subtrees
, void *data ATTRIBUTE_UNUSED
)
1604 if (! EXPR_P (t
) && ! GIMPLE_STMT_P (t
))
1607 if (DECL_P (t
) && DECL_RTL_SET_P (t
))
1608 instantiate_decl (DECL_RTL (t
));
1613 /* Subroutine of instantiate_decls: Process all decls in the given
1614 BLOCK node and all its subblocks. */
1617 instantiate_decls_1 (tree let
)
1621 for (t
= BLOCK_VARS (let
); t
; t
= TREE_CHAIN (t
))
1623 if (DECL_RTL_SET_P (t
))
1624 instantiate_decl (DECL_RTL (t
));
1625 if (TREE_CODE (t
) == VAR_DECL
&& DECL_HAS_VALUE_EXPR_P (t
))
1627 tree v
= DECL_VALUE_EXPR (t
);
1628 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1632 /* Process all subblocks. */
1633 for (t
= BLOCK_SUBBLOCKS (let
); t
; t
= TREE_CHAIN (t
))
1634 instantiate_decls_1 (t
);
1637 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1638 all virtual registers in their DECL_RTL's. */
1641 instantiate_decls (tree fndecl
)
1645 /* Process all parameters of the function. */
1646 for (decl
= DECL_ARGUMENTS (fndecl
); decl
; decl
= TREE_CHAIN (decl
))
1648 instantiate_decl (DECL_RTL (decl
));
1649 instantiate_decl (DECL_INCOMING_RTL (decl
));
1650 if (DECL_HAS_VALUE_EXPR_P (decl
))
1652 tree v
= DECL_VALUE_EXPR (decl
);
1653 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1657 /* Now process all variables defined in the function or its subblocks. */
1658 instantiate_decls_1 (DECL_INITIAL (fndecl
));
1661 /* Pass through the INSNS of function FNDECL and convert virtual register
1662 references to hard register references. */
1665 instantiate_virtual_regs (void)
1669 /* Compute the offsets to use for this function. */
1670 in_arg_offset
= FIRST_PARM_OFFSET (current_function_decl
);
1671 var_offset
= STARTING_FRAME_OFFSET
;
1672 dynamic_offset
= STACK_DYNAMIC_OFFSET (current_function_decl
);
1673 out_arg_offset
= STACK_POINTER_OFFSET
;
1674 #ifdef FRAME_POINTER_CFA_OFFSET
1675 cfa_offset
= FRAME_POINTER_CFA_OFFSET (current_function_decl
);
1677 cfa_offset
= ARG_POINTER_CFA_OFFSET (current_function_decl
);
1680 /* Initialize recognition, indicating that volatile is OK. */
1683 /* Scan through all the insns, instantiating every virtual register still
1685 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
1688 /* These patterns in the instruction stream can never be recognized.
1689 Fortunately, they shouldn't contain virtual registers either. */
1690 if (GET_CODE (PATTERN (insn
)) == USE
1691 || GET_CODE (PATTERN (insn
)) == CLOBBER
1692 || GET_CODE (PATTERN (insn
)) == ADDR_VEC
1693 || GET_CODE (PATTERN (insn
)) == ADDR_DIFF_VEC
1694 || GET_CODE (PATTERN (insn
)) == ASM_INPUT
)
1697 instantiate_virtual_regs_in_insn (insn
);
1699 if (INSN_DELETED_P (insn
))
1702 for_each_rtx (®_NOTES (insn
), instantiate_virtual_regs_in_rtx
, NULL
);
1704 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1705 if (GET_CODE (insn
) == CALL_INSN
)
1706 for_each_rtx (&CALL_INSN_FUNCTION_USAGE (insn
),
1707 instantiate_virtual_regs_in_rtx
, NULL
);
1710 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1711 instantiate_decls (current_function_decl
);
1713 /* Indicate that, from now on, assign_stack_local should use
1714 frame_pointer_rtx. */
1715 virtuals_instantiated
= 1;
1719 struct tree_opt_pass pass_instantiate_virtual_regs
=
1723 instantiate_virtual_regs
, /* execute */
1726 0, /* static_pass_number */
1728 0, /* properties_required */
1729 0, /* properties_provided */
1730 0, /* properties_destroyed */
1731 0, /* todo_flags_start */
1732 TODO_dump_func
, /* todo_flags_finish */
1737 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
1738 This means a type for which function calls must pass an address to the
1739 function or get an address back from the function.
1740 EXP may be a type node or an expression (whose type is tested). */
1743 aggregate_value_p (tree exp
, tree fntype
)
1745 int i
, regno
, nregs
;
1748 tree type
= (TYPE_P (exp
)) ? exp
: TREE_TYPE (exp
);
1750 /* DECL node associated with FNTYPE when relevant, which we might need to
1751 check for by-invisible-reference returns, typically for CALL_EXPR input
1753 tree fndecl
= NULL_TREE
;
1756 switch (TREE_CODE (fntype
))
1759 fndecl
= get_callee_fndecl (fntype
);
1760 fntype
= fndecl
? TREE_TYPE (fndecl
) : 0;
1764 fntype
= TREE_TYPE (fndecl
);
1769 case IDENTIFIER_NODE
:
1773 /* We don't expect other rtl types here. */
1777 if (TREE_CODE (type
) == VOID_TYPE
)
1780 /* If the front end has decided that this needs to be passed by
1781 reference, do so. */
1782 if ((TREE_CODE (exp
) == PARM_DECL
|| TREE_CODE (exp
) == RESULT_DECL
)
1783 && DECL_BY_REFERENCE (exp
))
1786 /* If the EXPression is a CALL_EXPR, honor DECL_BY_REFERENCE set on the
1787 called function RESULT_DECL, meaning the function returns in memory by
1788 invisible reference. This check lets front-ends not set TREE_ADDRESSABLE
1789 on the function type, which used to be the way to request such a return
1790 mechanism but might now be causing troubles at gimplification time if
1791 temporaries with the function type need to be created. */
1792 if (TREE_CODE (exp
) == CALL_EXPR
&& fndecl
&& DECL_RESULT (fndecl
)
1793 && DECL_BY_REFERENCE (DECL_RESULT (fndecl
)))
1796 if (targetm
.calls
.return_in_memory (type
, fntype
))
1798 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
1799 and thus can't be returned in registers. */
1800 if (TREE_ADDRESSABLE (type
))
1802 if (flag_pcc_struct_return
&& AGGREGATE_TYPE_P (type
))
1804 /* Make sure we have suitable call-clobbered regs to return
1805 the value in; if not, we must return it in memory. */
1806 reg
= hard_function_value (type
, 0, fntype
, 0);
1808 /* If we have something other than a REG (e.g. a PARALLEL), then assume
1813 regno
= REGNO (reg
);
1814 nregs
= hard_regno_nregs
[regno
][TYPE_MODE (type
)];
1815 for (i
= 0; i
< nregs
; i
++)
1816 if (! call_used_regs
[regno
+ i
])
1821 /* Return true if we should assign DECL a pseudo register; false if it
1822 should live on the local stack. */
1825 use_register_for_decl (tree decl
)
1827 /* Honor volatile. */
1828 if (TREE_SIDE_EFFECTS (decl
))
1831 /* Honor addressability. */
1832 if (TREE_ADDRESSABLE (decl
))
1835 /* Only register-like things go in registers. */
1836 if (DECL_MODE (decl
) == BLKmode
)
1839 /* If -ffloat-store specified, don't put explicit float variables
1841 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
1842 propagates values across these stores, and it probably shouldn't. */
1843 if (flag_float_store
&& FLOAT_TYPE_P (TREE_TYPE (decl
)))
1846 /* If we're not interested in tracking debugging information for
1847 this decl, then we can certainly put it in a register. */
1848 if (DECL_IGNORED_P (decl
))
1851 return (optimize
|| DECL_REGISTER (decl
));
1854 /* Return true if TYPE should be passed by invisible reference. */
1857 pass_by_reference (CUMULATIVE_ARGS
*ca
, enum machine_mode mode
,
1858 tree type
, bool named_arg
)
1862 /* If this type contains non-trivial constructors, then it is
1863 forbidden for the middle-end to create any new copies. */
1864 if (TREE_ADDRESSABLE (type
))
1867 /* GCC post 3.4 passes *all* variable sized types by reference. */
1868 if (!TYPE_SIZE (type
) || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
1872 return targetm
.calls
.pass_by_reference (ca
, mode
, type
, named_arg
);
1875 /* Return true if TYPE, which is passed by reference, should be callee
1876 copied instead of caller copied. */
1879 reference_callee_copied (CUMULATIVE_ARGS
*ca
, enum machine_mode mode
,
1880 tree type
, bool named_arg
)
1882 if (type
&& TREE_ADDRESSABLE (type
))
1884 return targetm
.calls
.callee_copies (ca
, mode
, type
, named_arg
);
1887 /* Structures to communicate between the subroutines of assign_parms.
1888 The first holds data persistent across all parameters, the second
1889 is cleared out for each parameter. */
1891 struct assign_parm_data_all
1893 CUMULATIVE_ARGS args_so_far
;
1894 struct args_size stack_args_size
;
1895 tree function_result_decl
;
1897 rtx conversion_insns
;
1898 HOST_WIDE_INT pretend_args_size
;
1899 HOST_WIDE_INT extra_pretend_bytes
;
1900 int reg_parm_stack_space
;
1903 struct assign_parm_data_one
1909 enum machine_mode nominal_mode
;
1910 enum machine_mode passed_mode
;
1911 enum machine_mode promoted_mode
;
1912 struct locate_and_pad_arg_data locate
;
1914 BOOL_BITFIELD named_arg
: 1;
1915 BOOL_BITFIELD passed_pointer
: 1;
1916 BOOL_BITFIELD on_stack
: 1;
1917 BOOL_BITFIELD loaded_in_reg
: 1;
1920 /* A subroutine of assign_parms. Initialize ALL. */
1923 assign_parms_initialize_all (struct assign_parm_data_all
*all
)
1927 memset (all
, 0, sizeof (*all
));
1929 fntype
= TREE_TYPE (current_function_decl
);
1931 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
1932 INIT_CUMULATIVE_INCOMING_ARGS (all
->args_so_far
, fntype
, NULL_RTX
);
1934 INIT_CUMULATIVE_ARGS (all
->args_so_far
, fntype
, NULL_RTX
,
1935 current_function_decl
, -1);
1938 #ifdef REG_PARM_STACK_SPACE
1939 all
->reg_parm_stack_space
= REG_PARM_STACK_SPACE (current_function_decl
);
1943 /* If ARGS contains entries with complex types, split the entry into two
1944 entries of the component type. Return a new list of substitutions are
1945 needed, else the old list. */
1948 split_complex_args (tree args
)
1952 /* Before allocating memory, check for the common case of no complex. */
1953 for (p
= args
; p
; p
= TREE_CHAIN (p
))
1955 tree type
= TREE_TYPE (p
);
1956 if (TREE_CODE (type
) == COMPLEX_TYPE
1957 && targetm
.calls
.split_complex_arg (type
))
1963 args
= copy_list (args
);
1965 for (p
= args
; p
; p
= TREE_CHAIN (p
))
1967 tree type
= TREE_TYPE (p
);
1968 if (TREE_CODE (type
) == COMPLEX_TYPE
1969 && targetm
.calls
.split_complex_arg (type
))
1972 tree subtype
= TREE_TYPE (type
);
1973 bool addressable
= TREE_ADDRESSABLE (p
);
1975 /* Rewrite the PARM_DECL's type with its component. */
1976 TREE_TYPE (p
) = subtype
;
1977 DECL_ARG_TYPE (p
) = TREE_TYPE (DECL_ARG_TYPE (p
));
1978 DECL_MODE (p
) = VOIDmode
;
1979 DECL_SIZE (p
) = NULL
;
1980 DECL_SIZE_UNIT (p
) = NULL
;
1981 /* If this arg must go in memory, put it in a pseudo here.
1982 We can't allow it to go in memory as per normal parms,
1983 because the usual place might not have the imag part
1984 adjacent to the real part. */
1985 DECL_ARTIFICIAL (p
) = addressable
;
1986 DECL_IGNORED_P (p
) = addressable
;
1987 TREE_ADDRESSABLE (p
) = 0;
1990 /* Build a second synthetic decl. */
1991 decl
= build_decl (PARM_DECL
, NULL_TREE
, subtype
);
1992 DECL_ARG_TYPE (decl
) = DECL_ARG_TYPE (p
);
1993 DECL_ARTIFICIAL (decl
) = addressable
;
1994 DECL_IGNORED_P (decl
) = addressable
;
1995 layout_decl (decl
, 0);
1997 /* Splice it in; skip the new decl. */
1998 TREE_CHAIN (decl
) = TREE_CHAIN (p
);
1999 TREE_CHAIN (p
) = decl
;
2007 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
2008 the hidden struct return argument, and (abi willing) complex args.
2009 Return the new parameter list. */
2012 assign_parms_augmented_arg_list (struct assign_parm_data_all
*all
)
2014 tree fndecl
= current_function_decl
;
2015 tree fntype
= TREE_TYPE (fndecl
);
2016 tree fnargs
= DECL_ARGUMENTS (fndecl
);
2018 /* If struct value address is treated as the first argument, make it so. */
2019 if (aggregate_value_p (DECL_RESULT (fndecl
), fndecl
)
2020 && ! current_function_returns_pcc_struct
2021 && targetm
.calls
.struct_value_rtx (TREE_TYPE (fndecl
), 1) == 0)
2023 tree type
= build_pointer_type (TREE_TYPE (fntype
));
2026 decl
= build_decl (PARM_DECL
, NULL_TREE
, type
);
2027 DECL_ARG_TYPE (decl
) = type
;
2028 DECL_ARTIFICIAL (decl
) = 1;
2029 DECL_IGNORED_P (decl
) = 1;
2031 TREE_CHAIN (decl
) = fnargs
;
2033 all
->function_result_decl
= decl
;
2036 all
->orig_fnargs
= fnargs
;
2038 /* If the target wants to split complex arguments into scalars, do so. */
2039 if (targetm
.calls
.split_complex_arg
)
2040 fnargs
= split_complex_args (fnargs
);
2045 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2046 data for the parameter. Incorporate ABI specifics such as pass-by-
2047 reference and type promotion. */
2050 assign_parm_find_data_types (struct assign_parm_data_all
*all
, tree parm
,
2051 struct assign_parm_data_one
*data
)
2053 tree nominal_type
, passed_type
;
2054 enum machine_mode nominal_mode
, passed_mode
, promoted_mode
;
2056 memset (data
, 0, sizeof (*data
));
2058 /* NAMED_ARG is a mis-nomer. We really mean 'non-varadic'. */
2059 if (!current_function_stdarg
)
2060 data
->named_arg
= 1; /* No varadic parms. */
2061 else if (TREE_CHAIN (parm
))
2062 data
->named_arg
= 1; /* Not the last non-varadic parm. */
2063 else if (targetm
.calls
.strict_argument_naming (&all
->args_so_far
))
2064 data
->named_arg
= 1; /* Only varadic ones are unnamed. */
2066 data
->named_arg
= 0; /* Treat as varadic. */
2068 nominal_type
= TREE_TYPE (parm
);
2069 passed_type
= DECL_ARG_TYPE (parm
);
2071 /* Look out for errors propagating this far. Also, if the parameter's
2072 type is void then its value doesn't matter. */
2073 if (TREE_TYPE (parm
) == error_mark_node
2074 /* This can happen after weird syntax errors
2075 or if an enum type is defined among the parms. */
2076 || TREE_CODE (parm
) != PARM_DECL
2077 || passed_type
== NULL
2078 || VOID_TYPE_P (nominal_type
))
2080 nominal_type
= passed_type
= void_type_node
;
2081 nominal_mode
= passed_mode
= promoted_mode
= VOIDmode
;
2085 /* Find mode of arg as it is passed, and mode of arg as it should be
2086 during execution of this function. */
2087 passed_mode
= TYPE_MODE (passed_type
);
2088 nominal_mode
= TYPE_MODE (nominal_type
);
2090 /* If the parm is to be passed as a transparent union, use the type of
2091 the first field for the tests below. We have already verified that
2092 the modes are the same. */
2093 if (TREE_CODE (passed_type
) == UNION_TYPE
2094 && TYPE_TRANSPARENT_UNION (passed_type
))
2095 passed_type
= TREE_TYPE (TYPE_FIELDS (passed_type
));
2097 /* See if this arg was passed by invisible reference. */
2098 if (pass_by_reference (&all
->args_so_far
, passed_mode
,
2099 passed_type
, data
->named_arg
))
2101 passed_type
= nominal_type
= build_pointer_type (passed_type
);
2102 data
->passed_pointer
= true;
2103 passed_mode
= nominal_mode
= Pmode
;
2106 /* Find mode as it is passed by the ABI. */
2107 promoted_mode
= passed_mode
;
2108 if (targetm
.calls
.promote_function_args (TREE_TYPE (current_function_decl
)))
2110 int unsignedp
= TYPE_UNSIGNED (passed_type
);
2111 promoted_mode
= promote_mode (passed_type
, promoted_mode
,
2116 data
->nominal_type
= nominal_type
;
2117 data
->passed_type
= passed_type
;
2118 data
->nominal_mode
= nominal_mode
;
2119 data
->passed_mode
= passed_mode
;
2120 data
->promoted_mode
= promoted_mode
;
2123 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2126 assign_parms_setup_varargs (struct assign_parm_data_all
*all
,
2127 struct assign_parm_data_one
*data
, bool no_rtl
)
2129 int varargs_pretend_bytes
= 0;
2131 targetm
.calls
.setup_incoming_varargs (&all
->args_so_far
,
2132 data
->promoted_mode
,
2134 &varargs_pretend_bytes
, no_rtl
);
2136 /* If the back-end has requested extra stack space, record how much is
2137 needed. Do not change pretend_args_size otherwise since it may be
2138 nonzero from an earlier partial argument. */
2139 if (varargs_pretend_bytes
> 0)
2140 all
->pretend_args_size
= varargs_pretend_bytes
;
2143 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2144 the incoming location of the current parameter. */
2147 assign_parm_find_entry_rtl (struct assign_parm_data_all
*all
,
2148 struct assign_parm_data_one
*data
)
2150 HOST_WIDE_INT pretend_bytes
= 0;
2154 if (data
->promoted_mode
== VOIDmode
)
2156 data
->entry_parm
= data
->stack_parm
= const0_rtx
;
2160 #ifdef FUNCTION_INCOMING_ARG
2161 entry_parm
= FUNCTION_INCOMING_ARG (all
->args_so_far
, data
->promoted_mode
,
2162 data
->passed_type
, data
->named_arg
);
2164 entry_parm
= FUNCTION_ARG (all
->args_so_far
, data
->promoted_mode
,
2165 data
->passed_type
, data
->named_arg
);
2168 if (entry_parm
== 0)
2169 data
->promoted_mode
= data
->passed_mode
;
2171 /* Determine parm's home in the stack, in case it arrives in the stack
2172 or we should pretend it did. Compute the stack position and rtx where
2173 the argument arrives and its size.
2175 There is one complexity here: If this was a parameter that would
2176 have been passed in registers, but wasn't only because it is
2177 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2178 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2179 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2180 as it was the previous time. */
2181 in_regs
= entry_parm
!= 0;
2182 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2185 if (!in_regs
&& !data
->named_arg
)
2187 if (targetm
.calls
.pretend_outgoing_varargs_named (&all
->args_so_far
))
2190 #ifdef FUNCTION_INCOMING_ARG
2191 tem
= FUNCTION_INCOMING_ARG (all
->args_so_far
, data
->promoted_mode
,
2192 data
->passed_type
, true);
2194 tem
= FUNCTION_ARG (all
->args_so_far
, data
->promoted_mode
,
2195 data
->passed_type
, true);
2197 in_regs
= tem
!= NULL
;
2201 /* If this parameter was passed both in registers and in the stack, use
2202 the copy on the stack. */
2203 if (targetm
.calls
.must_pass_in_stack (data
->promoted_mode
,
2211 partial
= targetm
.calls
.arg_partial_bytes (&all
->args_so_far
,
2212 data
->promoted_mode
,
2215 data
->partial
= partial
;
2217 /* The caller might already have allocated stack space for the
2218 register parameters. */
2219 if (partial
!= 0 && all
->reg_parm_stack_space
== 0)
2221 /* Part of this argument is passed in registers and part
2222 is passed on the stack. Ask the prologue code to extend
2223 the stack part so that we can recreate the full value.
2225 PRETEND_BYTES is the size of the registers we need to store.
2226 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2227 stack space that the prologue should allocate.
2229 Internally, gcc assumes that the argument pointer is aligned
2230 to STACK_BOUNDARY bits. This is used both for alignment
2231 optimizations (see init_emit) and to locate arguments that are
2232 aligned to more than PARM_BOUNDARY bits. We must preserve this
2233 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2234 a stack boundary. */
2236 /* We assume at most one partial arg, and it must be the first
2237 argument on the stack. */
2238 gcc_assert (!all
->extra_pretend_bytes
&& !all
->pretend_args_size
);
2240 pretend_bytes
= partial
;
2241 all
->pretend_args_size
= CEIL_ROUND (pretend_bytes
, STACK_BYTES
);
2243 /* We want to align relative to the actual stack pointer, so
2244 don't include this in the stack size until later. */
2245 all
->extra_pretend_bytes
= all
->pretend_args_size
;
2249 locate_and_pad_parm (data
->promoted_mode
, data
->passed_type
, in_regs
,
2250 entry_parm
? data
->partial
: 0, current_function_decl
,
2251 &all
->stack_args_size
, &data
->locate
);
2253 /* Adjust offsets to include the pretend args. */
2254 pretend_bytes
= all
->extra_pretend_bytes
- pretend_bytes
;
2255 data
->locate
.slot_offset
.constant
+= pretend_bytes
;
2256 data
->locate
.offset
.constant
+= pretend_bytes
;
2258 data
->entry_parm
= entry_parm
;
2261 /* A subroutine of assign_parms. If there is actually space on the stack
2262 for this parm, count it in stack_args_size and return true. */
2265 assign_parm_is_stack_parm (struct assign_parm_data_all
*all
,
2266 struct assign_parm_data_one
*data
)
2268 /* Trivially true if we've no incoming register. */
2269 if (data
->entry_parm
== NULL
)
2271 /* Also true if we're partially in registers and partially not,
2272 since we've arranged to drop the entire argument on the stack. */
2273 else if (data
->partial
!= 0)
2275 /* Also true if the target says that it's passed in both registers
2276 and on the stack. */
2277 else if (GET_CODE (data
->entry_parm
) == PARALLEL
2278 && XEXP (XVECEXP (data
->entry_parm
, 0, 0), 0) == NULL_RTX
)
2280 /* Also true if the target says that there's stack allocated for
2281 all register parameters. */
2282 else if (all
->reg_parm_stack_space
> 0)
2284 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2288 all
->stack_args_size
.constant
+= data
->locate
.size
.constant
;
2289 if (data
->locate
.size
.var
)
2290 ADD_PARM_SIZE (all
->stack_args_size
, data
->locate
.size
.var
);
2295 /* A subroutine of assign_parms. Given that this parameter is allocated
2296 stack space by the ABI, find it. */
2299 assign_parm_find_stack_rtl (tree parm
, struct assign_parm_data_one
*data
)
2301 rtx offset_rtx
, stack_parm
;
2302 unsigned int align
, boundary
;
2304 /* If we're passing this arg using a reg, make its stack home the
2305 aligned stack slot. */
2306 if (data
->entry_parm
)
2307 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.slot_offset
);
2309 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.offset
);
2311 stack_parm
= current_function_internal_arg_pointer
;
2312 if (offset_rtx
!= const0_rtx
)
2313 stack_parm
= gen_rtx_PLUS (Pmode
, stack_parm
, offset_rtx
);
2314 stack_parm
= gen_rtx_MEM (data
->promoted_mode
, stack_parm
);
2316 set_mem_attributes (stack_parm
, parm
, 1);
2318 boundary
= data
->locate
.boundary
;
2319 align
= BITS_PER_UNIT
;
2321 /* If we're padding upward, we know that the alignment of the slot
2322 is FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2323 intentionally forcing upward padding. Otherwise we have to come
2324 up with a guess at the alignment based on OFFSET_RTX. */
2325 if (data
->locate
.where_pad
!= downward
|| data
->entry_parm
)
2327 else if (GET_CODE (offset_rtx
) == CONST_INT
)
2329 align
= INTVAL (offset_rtx
) * BITS_PER_UNIT
| boundary
;
2330 align
= align
& -align
;
2332 set_mem_align (stack_parm
, align
);
2334 if (data
->entry_parm
)
2335 set_reg_attrs_for_parm (data
->entry_parm
, stack_parm
);
2337 data
->stack_parm
= stack_parm
;
2340 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2341 always valid and contiguous. */
2344 assign_parm_adjust_entry_rtl (struct assign_parm_data_one
*data
)
2346 rtx entry_parm
= data
->entry_parm
;
2347 rtx stack_parm
= data
->stack_parm
;
2349 /* If this parm was passed part in regs and part in memory, pretend it
2350 arrived entirely in memory by pushing the register-part onto the stack.
2351 In the special case of a DImode or DFmode that is split, we could put
2352 it together in a pseudoreg directly, but for now that's not worth
2354 if (data
->partial
!= 0)
2356 /* Handle calls that pass values in multiple non-contiguous
2357 locations. The Irix 6 ABI has examples of this. */
2358 if (GET_CODE (entry_parm
) == PARALLEL
)
2359 emit_group_store (validize_mem (stack_parm
), entry_parm
,
2361 int_size_in_bytes (data
->passed_type
));
2364 gcc_assert (data
->partial
% UNITS_PER_WORD
== 0);
2365 move_block_from_reg (REGNO (entry_parm
), validize_mem (stack_parm
),
2366 data
->partial
/ UNITS_PER_WORD
);
2369 entry_parm
= stack_parm
;
2372 /* If we didn't decide this parm came in a register, by default it came
2374 else if (entry_parm
== NULL
)
2375 entry_parm
= stack_parm
;
2377 /* When an argument is passed in multiple locations, we can't make use
2378 of this information, but we can save some copying if the whole argument
2379 is passed in a single register. */
2380 else if (GET_CODE (entry_parm
) == PARALLEL
2381 && data
->nominal_mode
!= BLKmode
2382 && data
->passed_mode
!= BLKmode
)
2384 size_t i
, len
= XVECLEN (entry_parm
, 0);
2386 for (i
= 0; i
< len
; i
++)
2387 if (XEXP (XVECEXP (entry_parm
, 0, i
), 0) != NULL_RTX
2388 && REG_P (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2389 && (GET_MODE (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2390 == data
->passed_mode
)
2391 && INTVAL (XEXP (XVECEXP (entry_parm
, 0, i
), 1)) == 0)
2393 entry_parm
= XEXP (XVECEXP (entry_parm
, 0, i
), 0);
2398 data
->entry_parm
= entry_parm
;
2401 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2402 always valid and properly aligned. */
2405 assign_parm_adjust_stack_rtl (struct assign_parm_data_one
*data
)
2407 rtx stack_parm
= data
->stack_parm
;
2409 /* If we can't trust the parm stack slot to be aligned enough for its
2410 ultimate type, don't use that slot after entry. We'll make another
2411 stack slot, if we need one. */
2413 && ((STRICT_ALIGNMENT
2414 && GET_MODE_ALIGNMENT (data
->nominal_mode
) > MEM_ALIGN (stack_parm
))
2415 || (data
->nominal_type
2416 && TYPE_ALIGN (data
->nominal_type
) > MEM_ALIGN (stack_parm
)
2417 && MEM_ALIGN (stack_parm
) < PREFERRED_STACK_BOUNDARY
)))
2420 /* If parm was passed in memory, and we need to convert it on entry,
2421 don't store it back in that same slot. */
2422 else if (data
->entry_parm
== stack_parm
2423 && data
->nominal_mode
!= BLKmode
2424 && data
->nominal_mode
!= data
->passed_mode
)
2427 /* If stack protection is in effect for this function, don't leave any
2428 pointers in their passed stack slots. */
2429 else if (cfun
->stack_protect_guard
2430 && (flag_stack_protect
== 2
2431 || data
->passed_pointer
2432 || POINTER_TYPE_P (data
->nominal_type
)))
2435 data
->stack_parm
= stack_parm
;
2438 /* A subroutine of assign_parms. Return true if the current parameter
2439 should be stored as a BLKmode in the current frame. */
2442 assign_parm_setup_block_p (struct assign_parm_data_one
*data
)
2444 if (data
->nominal_mode
== BLKmode
)
2446 if (GET_CODE (data
->entry_parm
) == PARALLEL
)
2449 #ifdef BLOCK_REG_PADDING
2450 /* Only assign_parm_setup_block knows how to deal with register arguments
2451 that are padded at the least significant end. */
2452 if (REG_P (data
->entry_parm
)
2453 && GET_MODE_SIZE (data
->promoted_mode
) < UNITS_PER_WORD
2454 && (BLOCK_REG_PADDING (data
->passed_mode
, data
->passed_type
, 1)
2455 == (BYTES_BIG_ENDIAN
? upward
: downward
)))
2462 /* A subroutine of assign_parms. Arrange for the parameter to be
2463 present and valid in DATA->STACK_RTL. */
2466 assign_parm_setup_block (struct assign_parm_data_all
*all
,
2467 tree parm
, struct assign_parm_data_one
*data
)
2469 rtx entry_parm
= data
->entry_parm
;
2470 rtx stack_parm
= data
->stack_parm
;
2472 HOST_WIDE_INT size_stored
;
2473 rtx orig_entry_parm
= entry_parm
;
2475 if (GET_CODE (entry_parm
) == PARALLEL
)
2476 entry_parm
= emit_group_move_into_temps (entry_parm
);
2478 /* If we've a non-block object that's nevertheless passed in parts,
2479 reconstitute it in register operations rather than on the stack. */
2480 if (GET_CODE (entry_parm
) == PARALLEL
2481 && data
->nominal_mode
!= BLKmode
)
2483 rtx elt0
= XEXP (XVECEXP (orig_entry_parm
, 0, 0), 0);
2485 if ((XVECLEN (entry_parm
, 0) > 1
2486 || hard_regno_nregs
[REGNO (elt0
)][GET_MODE (elt0
)] > 1)
2487 && use_register_for_decl (parm
))
2489 rtx parmreg
= gen_reg_rtx (data
->nominal_mode
);
2491 push_to_sequence (all
->conversion_insns
);
2493 /* For values returned in multiple registers, handle possible
2494 incompatible calls to emit_group_store.
2496 For example, the following would be invalid, and would have to
2497 be fixed by the conditional below:
2499 emit_group_store ((reg:SF), (parallel:DF))
2500 emit_group_store ((reg:SI), (parallel:DI))
2502 An example of this are doubles in e500 v2:
2503 (parallel:DF (expr_list (reg:SI) (const_int 0))
2504 (expr_list (reg:SI) (const_int 4))). */
2505 if (data
->nominal_mode
!= data
->passed_mode
)
2507 rtx t
= gen_reg_rtx (GET_MODE (entry_parm
));
2508 emit_group_store (t
, entry_parm
, NULL_TREE
,
2509 GET_MODE_SIZE (GET_MODE (entry_parm
)));
2510 convert_move (parmreg
, t
, 0);
2513 emit_group_store (parmreg
, entry_parm
, data
->nominal_type
,
2514 int_size_in_bytes (data
->nominal_type
));
2516 all
->conversion_insns
= get_insns ();
2519 SET_DECL_RTL (parm
, parmreg
);
2524 size
= int_size_in_bytes (data
->passed_type
);
2525 size_stored
= CEIL_ROUND (size
, UNITS_PER_WORD
);
2526 if (stack_parm
== 0)
2528 DECL_ALIGN (parm
) = MAX (DECL_ALIGN (parm
), BITS_PER_WORD
);
2529 stack_parm
= assign_stack_local (BLKmode
, size_stored
,
2531 if (GET_MODE_SIZE (GET_MODE (entry_parm
)) == size
)
2532 PUT_MODE (stack_parm
, GET_MODE (entry_parm
));
2533 set_mem_attributes (stack_parm
, parm
, 1);
2536 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2537 calls that pass values in multiple non-contiguous locations. */
2538 if (REG_P (entry_parm
) || GET_CODE (entry_parm
) == PARALLEL
)
2542 /* Note that we will be storing an integral number of words.
2543 So we have to be careful to ensure that we allocate an
2544 integral number of words. We do this above when we call
2545 assign_stack_local if space was not allocated in the argument
2546 list. If it was, this will not work if PARM_BOUNDARY is not
2547 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2548 if it becomes a problem. Exception is when BLKmode arrives
2549 with arguments not conforming to word_mode. */
2551 if (data
->stack_parm
== 0)
2553 else if (GET_CODE (entry_parm
) == PARALLEL
)
2556 gcc_assert (!size
|| !(PARM_BOUNDARY
% BITS_PER_WORD
));
2558 mem
= validize_mem (stack_parm
);
2560 /* Handle values in multiple non-contiguous locations. */
2561 if (GET_CODE (entry_parm
) == PARALLEL
)
2563 push_to_sequence (all
->conversion_insns
);
2564 emit_group_store (mem
, entry_parm
, data
->passed_type
, size
);
2565 all
->conversion_insns
= get_insns ();
2572 /* If SIZE is that of a mode no bigger than a word, just use
2573 that mode's store operation. */
2574 else if (size
<= UNITS_PER_WORD
)
2576 enum machine_mode mode
2577 = mode_for_size (size
* BITS_PER_UNIT
, MODE_INT
, 0);
2580 #ifdef BLOCK_REG_PADDING
2581 && (size
== UNITS_PER_WORD
2582 || (BLOCK_REG_PADDING (mode
, data
->passed_type
, 1)
2583 != (BYTES_BIG_ENDIAN
? upward
: downward
)))
2587 rtx reg
= gen_rtx_REG (mode
, REGNO (entry_parm
));
2588 emit_move_insn (change_address (mem
, mode
, 0), reg
);
2591 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
2592 machine must be aligned to the left before storing
2593 to memory. Note that the previous test doesn't
2594 handle all cases (e.g. SIZE == 3). */
2595 else if (size
!= UNITS_PER_WORD
2596 #ifdef BLOCK_REG_PADDING
2597 && (BLOCK_REG_PADDING (mode
, data
->passed_type
, 1)
2605 int by
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
2606 rtx reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
2608 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
,
2609 build_int_cst (NULL_TREE
, by
),
2611 tem
= change_address (mem
, word_mode
, 0);
2612 emit_move_insn (tem
, x
);
2615 move_block_from_reg (REGNO (entry_parm
), mem
,
2616 size_stored
/ UNITS_PER_WORD
);
2619 move_block_from_reg (REGNO (entry_parm
), mem
,
2620 size_stored
/ UNITS_PER_WORD
);
2622 else if (data
->stack_parm
== 0)
2624 push_to_sequence (all
->conversion_insns
);
2625 emit_block_move (stack_parm
, data
->entry_parm
, GEN_INT (size
),
2627 all
->conversion_insns
= get_insns ();
2631 data
->stack_parm
= stack_parm
;
2632 SET_DECL_RTL (parm
, stack_parm
);
2635 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
2636 parameter. Get it there. Perform all ABI specified conversions. */
2639 assign_parm_setup_reg (struct assign_parm_data_all
*all
, tree parm
,
2640 struct assign_parm_data_one
*data
)
2643 enum machine_mode promoted_nominal_mode
;
2644 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (parm
));
2645 bool did_conversion
= false;
2647 /* Store the parm in a pseudoregister during the function, but we may
2648 need to do it in a wider mode. */
2650 /* This is not really promoting for a call. However we need to be
2651 consistent with assign_parm_find_data_types and expand_expr_real_1. */
2652 promoted_nominal_mode
2653 = promote_mode (data
->nominal_type
, data
->nominal_mode
, &unsignedp
, 1);
2655 parmreg
= gen_reg_rtx (promoted_nominal_mode
);
2657 if (!DECL_ARTIFICIAL (parm
))
2658 mark_user_reg (parmreg
);
2660 /* If this was an item that we received a pointer to,
2661 set DECL_RTL appropriately. */
2662 if (data
->passed_pointer
)
2664 rtx x
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data
->passed_type
)), parmreg
);
2665 set_mem_attributes (x
, parm
, 1);
2666 SET_DECL_RTL (parm
, x
);
2669 SET_DECL_RTL (parm
, parmreg
);
2671 /* Copy the value into the register. */
2672 if (data
->nominal_mode
!= data
->passed_mode
2673 || promoted_nominal_mode
!= data
->promoted_mode
)
2677 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
2678 mode, by the caller. We now have to convert it to
2679 NOMINAL_MODE, if different. However, PARMREG may be in
2680 a different mode than NOMINAL_MODE if it is being stored
2683 If ENTRY_PARM is a hard register, it might be in a register
2684 not valid for operating in its mode (e.g., an odd-numbered
2685 register for a DFmode). In that case, moves are the only
2686 thing valid, so we can't do a convert from there. This
2687 occurs when the calling sequence allow such misaligned
2690 In addition, the conversion may involve a call, which could
2691 clobber parameters which haven't been copied to pseudo
2692 registers yet. Therefore, we must first copy the parm to
2693 a pseudo reg here, and save the conversion until after all
2694 parameters have been moved. */
2696 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
2698 emit_move_insn (tempreg
, validize_mem (data
->entry_parm
));
2700 push_to_sequence (all
->conversion_insns
);
2701 tempreg
= convert_to_mode (data
->nominal_mode
, tempreg
, unsignedp
);
2703 if (GET_CODE (tempreg
) == SUBREG
2704 && GET_MODE (tempreg
) == data
->nominal_mode
2705 && REG_P (SUBREG_REG (tempreg
))
2706 && data
->nominal_mode
== data
->passed_mode
2707 && GET_MODE (SUBREG_REG (tempreg
)) == GET_MODE (data
->entry_parm
)
2708 && GET_MODE_SIZE (GET_MODE (tempreg
))
2709 < GET_MODE_SIZE (GET_MODE (data
->entry_parm
)))
2711 /* The argument is already sign/zero extended, so note it
2713 SUBREG_PROMOTED_VAR_P (tempreg
) = 1;
2714 SUBREG_PROMOTED_UNSIGNED_SET (tempreg
, unsignedp
);
2717 /* TREE_USED gets set erroneously during expand_assignment. */
2718 save_tree_used
= TREE_USED (parm
);
2719 expand_assignment (parm
, make_tree (data
->nominal_type
, tempreg
));
2720 TREE_USED (parm
) = save_tree_used
;
2721 all
->conversion_insns
= get_insns ();
2724 did_conversion
= true;
2727 emit_move_insn (parmreg
, validize_mem (data
->entry_parm
));
2729 /* If we were passed a pointer but the actual value can safely live
2730 in a register, put it in one. */
2731 if (data
->passed_pointer
2732 && TYPE_MODE (TREE_TYPE (parm
)) != BLKmode
2733 /* If by-reference argument was promoted, demote it. */
2734 && (TYPE_MODE (TREE_TYPE (parm
)) != GET_MODE (DECL_RTL (parm
))
2735 || use_register_for_decl (parm
)))
2737 /* We can't use nominal_mode, because it will have been set to
2738 Pmode above. We must use the actual mode of the parm. */
2739 parmreg
= gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm
)));
2740 mark_user_reg (parmreg
);
2742 if (GET_MODE (parmreg
) != GET_MODE (DECL_RTL (parm
)))
2744 rtx tempreg
= gen_reg_rtx (GET_MODE (DECL_RTL (parm
)));
2745 int unsigned_p
= TYPE_UNSIGNED (TREE_TYPE (parm
));
2747 push_to_sequence (all
->conversion_insns
);
2748 emit_move_insn (tempreg
, DECL_RTL (parm
));
2749 tempreg
= convert_to_mode (GET_MODE (parmreg
), tempreg
, unsigned_p
);
2750 emit_move_insn (parmreg
, tempreg
);
2751 all
->conversion_insns
= get_insns ();
2754 did_conversion
= true;
2757 emit_move_insn (parmreg
, DECL_RTL (parm
));
2759 SET_DECL_RTL (parm
, parmreg
);
2761 /* STACK_PARM is the pointer, not the parm, and PARMREG is
2763 data
->stack_parm
= NULL
;
2766 /* Mark the register as eliminable if we did no conversion and it was
2767 copied from memory at a fixed offset, and the arg pointer was not
2768 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
2769 offset formed an invalid address, such memory-equivalences as we
2770 make here would screw up life analysis for it. */
2771 if (data
->nominal_mode
== data
->passed_mode
2773 && data
->stack_parm
!= 0
2774 && MEM_P (data
->stack_parm
)
2775 && data
->locate
.offset
.var
== 0
2776 && reg_mentioned_p (virtual_incoming_args_rtx
,
2777 XEXP (data
->stack_parm
, 0)))
2779 rtx linsn
= get_last_insn ();
2782 /* Mark complex types separately. */
2783 if (GET_CODE (parmreg
) == CONCAT
)
2785 enum machine_mode submode
2786 = GET_MODE_INNER (GET_MODE (parmreg
));
2787 int regnor
= REGNO (XEXP (parmreg
, 0));
2788 int regnoi
= REGNO (XEXP (parmreg
, 1));
2789 rtx stackr
= adjust_address_nv (data
->stack_parm
, submode
, 0);
2790 rtx stacki
= adjust_address_nv (data
->stack_parm
, submode
,
2791 GET_MODE_SIZE (submode
));
2793 /* Scan backwards for the set of the real and
2795 for (sinsn
= linsn
; sinsn
!= 0;
2796 sinsn
= prev_nonnote_insn (sinsn
))
2798 set
= single_set (sinsn
);
2802 if (SET_DEST (set
) == regno_reg_rtx
[regnoi
])
2803 set_unique_reg_note (sinsn
, REG_EQUIV
, stacki
);
2804 else if (SET_DEST (set
) == regno_reg_rtx
[regnor
])
2805 set_unique_reg_note (sinsn
, REG_EQUIV
, stackr
);
2808 else if ((set
= single_set (linsn
)) != 0
2809 && SET_DEST (set
) == parmreg
)
2810 set_unique_reg_note (linsn
, REG_EQUIV
, data
->stack_parm
);
2813 /* For pointer data type, suggest pointer register. */
2814 if (POINTER_TYPE_P (TREE_TYPE (parm
)))
2815 mark_reg_pointer (parmreg
,
2816 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
2819 /* A subroutine of assign_parms. Allocate stack space to hold the current
2820 parameter. Get it there. Perform all ABI specified conversions. */
2823 assign_parm_setup_stack (struct assign_parm_data_all
*all
, tree parm
,
2824 struct assign_parm_data_one
*data
)
2826 /* Value must be stored in the stack slot STACK_PARM during function
2828 bool to_conversion
= false;
2830 if (data
->promoted_mode
!= data
->nominal_mode
)
2832 /* Conversion is required. */
2833 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
2835 emit_move_insn (tempreg
, validize_mem (data
->entry_parm
));
2837 push_to_sequence (all
->conversion_insns
);
2838 to_conversion
= true;
2840 data
->entry_parm
= convert_to_mode (data
->nominal_mode
, tempreg
,
2841 TYPE_UNSIGNED (TREE_TYPE (parm
)));
2843 if (data
->stack_parm
)
2844 /* ??? This may need a big-endian conversion on sparc64. */
2846 = adjust_address (data
->stack_parm
, data
->nominal_mode
, 0);
2849 if (data
->entry_parm
!= data
->stack_parm
)
2853 if (data
->stack_parm
== 0)
2856 = assign_stack_local (GET_MODE (data
->entry_parm
),
2857 GET_MODE_SIZE (GET_MODE (data
->entry_parm
)),
2858 TYPE_ALIGN (data
->passed_type
));
2859 set_mem_attributes (data
->stack_parm
, parm
, 1);
2862 dest
= validize_mem (data
->stack_parm
);
2863 src
= validize_mem (data
->entry_parm
);
2867 /* Use a block move to handle potentially misaligned entry_parm. */
2869 push_to_sequence (all
->conversion_insns
);
2870 to_conversion
= true;
2872 emit_block_move (dest
, src
,
2873 GEN_INT (int_size_in_bytes (data
->passed_type
)),
2877 emit_move_insn (dest
, src
);
2882 all
->conversion_insns
= get_insns ();
2886 SET_DECL_RTL (parm
, data
->stack_parm
);
2889 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
2890 undo the frobbing that we did in assign_parms_augmented_arg_list. */
2893 assign_parms_unsplit_complex (struct assign_parm_data_all
*all
, tree fnargs
)
2896 tree orig_fnargs
= all
->orig_fnargs
;
2898 for (parm
= orig_fnargs
; parm
; parm
= TREE_CHAIN (parm
))
2900 if (TREE_CODE (TREE_TYPE (parm
)) == COMPLEX_TYPE
2901 && targetm
.calls
.split_complex_arg (TREE_TYPE (parm
)))
2903 rtx tmp
, real
, imag
;
2904 enum machine_mode inner
= GET_MODE_INNER (DECL_MODE (parm
));
2906 real
= DECL_RTL (fnargs
);
2907 imag
= DECL_RTL (TREE_CHAIN (fnargs
));
2908 if (inner
!= GET_MODE (real
))
2910 real
= gen_lowpart_SUBREG (inner
, real
);
2911 imag
= gen_lowpart_SUBREG (inner
, imag
);
2914 if (TREE_ADDRESSABLE (parm
))
2917 HOST_WIDE_INT size
= int_size_in_bytes (TREE_TYPE (parm
));
2919 /* split_complex_arg put the real and imag parts in
2920 pseudos. Move them to memory. */
2921 tmp
= assign_stack_local (DECL_MODE (parm
), size
,
2922 TYPE_ALIGN (TREE_TYPE (parm
)));
2923 set_mem_attributes (tmp
, parm
, 1);
2924 rmem
= adjust_address_nv (tmp
, inner
, 0);
2925 imem
= adjust_address_nv (tmp
, inner
, GET_MODE_SIZE (inner
));
2926 push_to_sequence (all
->conversion_insns
);
2927 emit_move_insn (rmem
, real
);
2928 emit_move_insn (imem
, imag
);
2929 all
->conversion_insns
= get_insns ();
2933 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
2934 SET_DECL_RTL (parm
, tmp
);
2936 real
= DECL_INCOMING_RTL (fnargs
);
2937 imag
= DECL_INCOMING_RTL (TREE_CHAIN (fnargs
));
2938 if (inner
!= GET_MODE (real
))
2940 real
= gen_lowpart_SUBREG (inner
, real
);
2941 imag
= gen_lowpart_SUBREG (inner
, imag
);
2943 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
2944 set_decl_incoming_rtl (parm
, tmp
);
2945 fnargs
= TREE_CHAIN (fnargs
);
2949 SET_DECL_RTL (parm
, DECL_RTL (fnargs
));
2950 set_decl_incoming_rtl (parm
, DECL_INCOMING_RTL (fnargs
));
2952 /* Set MEM_EXPR to the original decl, i.e. to PARM,
2953 instead of the copy of decl, i.e. FNARGS. */
2954 if (DECL_INCOMING_RTL (parm
) && MEM_P (DECL_INCOMING_RTL (parm
)))
2955 set_mem_expr (DECL_INCOMING_RTL (parm
), parm
);
2958 fnargs
= TREE_CHAIN (fnargs
);
2962 /* Assign RTL expressions to the function's parameters. This may involve
2963 copying them into registers and using those registers as the DECL_RTL. */
2966 assign_parms (tree fndecl
)
2968 struct assign_parm_data_all all
;
2971 current_function_internal_arg_pointer
2972 = targetm
.calls
.internal_arg_pointer ();
2974 assign_parms_initialize_all (&all
);
2975 fnargs
= assign_parms_augmented_arg_list (&all
);
2977 for (parm
= fnargs
; parm
; parm
= TREE_CHAIN (parm
))
2979 struct assign_parm_data_one data
;
2981 /* Extract the type of PARM; adjust it according to ABI. */
2982 assign_parm_find_data_types (&all
, parm
, &data
);
2984 /* Early out for errors and void parameters. */
2985 if (data
.passed_mode
== VOIDmode
)
2987 SET_DECL_RTL (parm
, const0_rtx
);
2988 DECL_INCOMING_RTL (parm
) = DECL_RTL (parm
);
2992 if (current_function_stdarg
&& !TREE_CHAIN (parm
))
2993 assign_parms_setup_varargs (&all
, &data
, false);
2995 /* Find out where the parameter arrives in this function. */
2996 assign_parm_find_entry_rtl (&all
, &data
);
2998 /* Find out where stack space for this parameter might be. */
2999 if (assign_parm_is_stack_parm (&all
, &data
))
3001 assign_parm_find_stack_rtl (parm
, &data
);
3002 assign_parm_adjust_entry_rtl (&data
);
3005 /* Record permanently how this parm was passed. */
3006 set_decl_incoming_rtl (parm
, data
.entry_parm
);
3008 /* Update info on where next arg arrives in registers. */
3009 FUNCTION_ARG_ADVANCE (all
.args_so_far
, data
.promoted_mode
,
3010 data
.passed_type
, data
.named_arg
);
3012 assign_parm_adjust_stack_rtl (&data
);
3014 if (assign_parm_setup_block_p (&data
))
3015 assign_parm_setup_block (&all
, parm
, &data
);
3016 else if (data
.passed_pointer
|| use_register_for_decl (parm
))
3017 assign_parm_setup_reg (&all
, parm
, &data
);
3019 assign_parm_setup_stack (&all
, parm
, &data
);
3022 if (targetm
.calls
.split_complex_arg
&& fnargs
!= all
.orig_fnargs
)
3023 assign_parms_unsplit_complex (&all
, fnargs
);
3025 /* Output all parameter conversion instructions (possibly including calls)
3026 now that all parameters have been copied out of hard registers. */
3027 emit_insn (all
.conversion_insns
);
3029 /* If we are receiving a struct value address as the first argument, set up
3030 the RTL for the function result. As this might require code to convert
3031 the transmitted address to Pmode, we do this here to ensure that possible
3032 preliminary conversions of the address have been emitted already. */
3033 if (all
.function_result_decl
)
3035 tree result
= DECL_RESULT (current_function_decl
);
3036 rtx addr
= DECL_RTL (all
.function_result_decl
);
3039 if (DECL_BY_REFERENCE (result
))
3043 addr
= convert_memory_address (Pmode
, addr
);
3044 x
= gen_rtx_MEM (DECL_MODE (result
), addr
);
3045 set_mem_attributes (x
, result
, 1);
3047 SET_DECL_RTL (result
, x
);
3050 /* We have aligned all the args, so add space for the pretend args. */
3051 current_function_pretend_args_size
= all
.pretend_args_size
;
3052 all
.stack_args_size
.constant
+= all
.extra_pretend_bytes
;
3053 current_function_args_size
= all
.stack_args_size
.constant
;
3055 /* Adjust function incoming argument size for alignment and
3058 #ifdef REG_PARM_STACK_SPACE
3059 current_function_args_size
= MAX (current_function_args_size
,
3060 REG_PARM_STACK_SPACE (fndecl
));
3063 current_function_args_size
= CEIL_ROUND (current_function_args_size
,
3064 PARM_BOUNDARY
/ BITS_PER_UNIT
);
3066 #ifdef ARGS_GROW_DOWNWARD
3067 current_function_arg_offset_rtx
3068 = (all
.stack_args_size
.var
== 0 ? GEN_INT (-all
.stack_args_size
.constant
)
3069 : expand_expr (size_diffop (all
.stack_args_size
.var
,
3070 size_int (-all
.stack_args_size
.constant
)),
3071 NULL_RTX
, VOIDmode
, 0));
3073 current_function_arg_offset_rtx
= ARGS_SIZE_RTX (all
.stack_args_size
);
3076 /* See how many bytes, if any, of its args a function should try to pop
3079 current_function_pops_args
= RETURN_POPS_ARGS (fndecl
, TREE_TYPE (fndecl
),
3080 current_function_args_size
);
3082 /* For stdarg.h function, save info about
3083 regs and stack space used by the named args. */
3085 current_function_args_info
= all
.args_so_far
;
3087 /* Set the rtx used for the function return value. Put this in its
3088 own variable so any optimizers that need this information don't have
3089 to include tree.h. Do this here so it gets done when an inlined
3090 function gets output. */
3092 current_function_return_rtx
3093 = (DECL_RTL_SET_P (DECL_RESULT (fndecl
))
3094 ? DECL_RTL (DECL_RESULT (fndecl
)) : NULL_RTX
);
3096 /* If scalar return value was computed in a pseudo-reg, or was a named
3097 return value that got dumped to the stack, copy that to the hard
3099 if (DECL_RTL_SET_P (DECL_RESULT (fndecl
)))
3101 tree decl_result
= DECL_RESULT (fndecl
);
3102 rtx decl_rtl
= DECL_RTL (decl_result
);
3104 if (REG_P (decl_rtl
)
3105 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
3106 : DECL_REGISTER (decl_result
))
3110 real_decl_rtl
= targetm
.calls
.function_value (TREE_TYPE (decl_result
),
3112 REG_FUNCTION_VALUE_P (real_decl_rtl
) = 1;
3113 /* The delay slot scheduler assumes that current_function_return_rtx
3114 holds the hard register containing the return value, not a
3115 temporary pseudo. */
3116 current_function_return_rtx
= real_decl_rtl
;
3121 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3122 For all seen types, gimplify their sizes. */
3125 gimplify_parm_type (tree
*tp
, int *walk_subtrees
, void *data
)
3132 if (POINTER_TYPE_P (t
))
3134 else if (TYPE_SIZE (t
) && !TREE_CONSTANT (TYPE_SIZE (t
))
3135 && !TYPE_SIZES_GIMPLIFIED (t
))
3137 gimplify_type_sizes (t
, (tree
*) data
);
3145 /* Gimplify the parameter list for current_function_decl. This involves
3146 evaluating SAVE_EXPRs of variable sized parameters and generating code
3147 to implement callee-copies reference parameters. Returns a list of
3148 statements to add to the beginning of the function, or NULL if nothing
3152 gimplify_parameters (void)
3154 struct assign_parm_data_all all
;
3155 tree fnargs
, parm
, stmts
= NULL
;
3157 assign_parms_initialize_all (&all
);
3158 fnargs
= assign_parms_augmented_arg_list (&all
);
3160 for (parm
= fnargs
; parm
; parm
= TREE_CHAIN (parm
))
3162 struct assign_parm_data_one data
;
3164 /* Extract the type of PARM; adjust it according to ABI. */
3165 assign_parm_find_data_types (&all
, parm
, &data
);
3167 /* Early out for errors and void parameters. */
3168 if (data
.passed_mode
== VOIDmode
|| DECL_SIZE (parm
) == NULL
)
3171 /* Update info on where next arg arrives in registers. */
3172 FUNCTION_ARG_ADVANCE (all
.args_so_far
, data
.promoted_mode
,
3173 data
.passed_type
, data
.named_arg
);
3175 /* ??? Once upon a time variable_size stuffed parameter list
3176 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3177 turned out to be less than manageable in the gimple world.
3178 Now we have to hunt them down ourselves. */
3179 walk_tree_without_duplicates (&data
.passed_type
,
3180 gimplify_parm_type
, &stmts
);
3182 if (!TREE_CONSTANT (DECL_SIZE (parm
)))
3184 gimplify_one_sizepos (&DECL_SIZE (parm
), &stmts
);
3185 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm
), &stmts
);
3188 if (data
.passed_pointer
)
3190 tree type
= TREE_TYPE (data
.passed_type
);
3191 if (reference_callee_copied (&all
.args_so_far
, TYPE_MODE (type
),
3192 type
, data
.named_arg
))
3196 /* For constant sized objects, this is trivial; for
3197 variable-sized objects, we have to play games. */
3198 if (TREE_CONSTANT (DECL_SIZE (parm
)))
3200 local
= create_tmp_var (type
, get_name (parm
));
3201 DECL_IGNORED_P (local
) = 0;
3205 tree ptr_type
, addr
, args
;
3207 ptr_type
= build_pointer_type (type
);
3208 addr
= create_tmp_var (ptr_type
, get_name (parm
));
3209 DECL_IGNORED_P (addr
) = 0;
3210 local
= build_fold_indirect_ref (addr
);
3212 args
= tree_cons (NULL
, DECL_SIZE_UNIT (parm
), NULL
);
3213 t
= built_in_decls
[BUILT_IN_ALLOCA
];
3214 t
= build_function_call_expr (t
, args
);
3215 t
= fold_convert (ptr_type
, t
);
3216 t
= build2 (GIMPLE_MODIFY_STMT
, void_type_node
, addr
, t
);
3217 gimplify_and_add (t
, &stmts
);
3220 t
= build2 (GIMPLE_MODIFY_STMT
, void_type_node
, local
, parm
);
3221 gimplify_and_add (t
, &stmts
);
3223 SET_DECL_VALUE_EXPR (parm
, local
);
3224 DECL_HAS_VALUE_EXPR_P (parm
) = 1;
3232 /* Indicate whether REGNO is an incoming argument to the current function
3233 that was promoted to a wider mode. If so, return the RTX for the
3234 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
3235 that REGNO is promoted from and whether the promotion was signed or
3239 promoted_input_arg (unsigned int regno
, enum machine_mode
*pmode
, int *punsignedp
)
3243 for (arg
= DECL_ARGUMENTS (current_function_decl
); arg
;
3244 arg
= TREE_CHAIN (arg
))
3245 if (REG_P (DECL_INCOMING_RTL (arg
))
3246 && REGNO (DECL_INCOMING_RTL (arg
)) == regno
3247 && TYPE_MODE (DECL_ARG_TYPE (arg
)) == TYPE_MODE (TREE_TYPE (arg
)))
3249 enum machine_mode mode
= TYPE_MODE (TREE_TYPE (arg
));
3250 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (arg
));
3252 mode
= promote_mode (TREE_TYPE (arg
), mode
, &unsignedp
, 1);
3253 if (mode
== GET_MODE (DECL_INCOMING_RTL (arg
))
3254 && mode
!= DECL_MODE (arg
))
3256 *pmode
= DECL_MODE (arg
);
3257 *punsignedp
= unsignedp
;
3258 return DECL_INCOMING_RTL (arg
);
3266 /* Compute the size and offset from the start of the stacked arguments for a
3267 parm passed in mode PASSED_MODE and with type TYPE.
3269 INITIAL_OFFSET_PTR points to the current offset into the stacked
3272 The starting offset and size for this parm are returned in
3273 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3274 nonzero, the offset is that of stack slot, which is returned in
3275 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3276 padding required from the initial offset ptr to the stack slot.
3278 IN_REGS is nonzero if the argument will be passed in registers. It will
3279 never be set if REG_PARM_STACK_SPACE is not defined.
3281 FNDECL is the function in which the argument was defined.
3283 There are two types of rounding that are done. The first, controlled by
3284 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
3285 list to be aligned to the specific boundary (in bits). This rounding
3286 affects the initial and starting offsets, but not the argument size.
3288 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3289 optionally rounds the size of the parm to PARM_BOUNDARY. The
3290 initial offset is not affected by this rounding, while the size always
3291 is and the starting offset may be. */
3293 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3294 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3295 callers pass in the total size of args so far as
3296 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
3299 locate_and_pad_parm (enum machine_mode passed_mode
, tree type
, int in_regs
,
3300 int partial
, tree fndecl ATTRIBUTE_UNUSED
,
3301 struct args_size
*initial_offset_ptr
,
3302 struct locate_and_pad_arg_data
*locate
)
3305 enum direction where_pad
;
3306 unsigned int boundary
;
3307 int reg_parm_stack_space
= 0;
3308 int part_size_in_regs
;
3310 #ifdef REG_PARM_STACK_SPACE
3311 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
3313 /* If we have found a stack parm before we reach the end of the
3314 area reserved for registers, skip that area. */
3317 if (reg_parm_stack_space
> 0)
3319 if (initial_offset_ptr
->var
)
3321 initial_offset_ptr
->var
3322 = size_binop (MAX_EXPR
, ARGS_SIZE_TREE (*initial_offset_ptr
),
3323 ssize_int (reg_parm_stack_space
));
3324 initial_offset_ptr
->constant
= 0;
3326 else if (initial_offset_ptr
->constant
< reg_parm_stack_space
)
3327 initial_offset_ptr
->constant
= reg_parm_stack_space
;
3330 #endif /* REG_PARM_STACK_SPACE */
3332 part_size_in_regs
= (reg_parm_stack_space
== 0 ? partial
: 0);
3335 = type
? size_in_bytes (type
) : size_int (GET_MODE_SIZE (passed_mode
));
3336 where_pad
= FUNCTION_ARG_PADDING (passed_mode
, type
);
3337 boundary
= FUNCTION_ARG_BOUNDARY (passed_mode
, type
);
3338 locate
->where_pad
= where_pad
;
3339 locate
->boundary
= boundary
;
3341 /* Remember if the outgoing parameter requires extra alignment on the
3342 calling function side. */
3343 if (boundary
> PREFERRED_STACK_BOUNDARY
)
3344 boundary
= PREFERRED_STACK_BOUNDARY
;
3345 if (cfun
->stack_alignment_needed
< boundary
)
3346 cfun
->stack_alignment_needed
= boundary
;
3348 #ifdef ARGS_GROW_DOWNWARD
3349 locate
->slot_offset
.constant
= -initial_offset_ptr
->constant
;
3350 if (initial_offset_ptr
->var
)
3351 locate
->slot_offset
.var
= size_binop (MINUS_EXPR
, ssize_int (0),
3352 initial_offset_ptr
->var
);
3356 if (where_pad
!= none
3357 && (!host_integerp (sizetree
, 1)
3358 || (tree_low_cst (sizetree
, 1) * BITS_PER_UNIT
) % PARM_BOUNDARY
))
3359 s2
= round_up (s2
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3360 SUB_PARM_SIZE (locate
->slot_offset
, s2
);
3363 locate
->slot_offset
.constant
+= part_size_in_regs
;
3366 #ifdef REG_PARM_STACK_SPACE
3367 || REG_PARM_STACK_SPACE (fndecl
) > 0
3370 pad_to_arg_alignment (&locate
->slot_offset
, boundary
,
3371 &locate
->alignment_pad
);
3373 locate
->size
.constant
= (-initial_offset_ptr
->constant
3374 - locate
->slot_offset
.constant
);
3375 if (initial_offset_ptr
->var
)
3376 locate
->size
.var
= size_binop (MINUS_EXPR
,
3377 size_binop (MINUS_EXPR
,
3379 initial_offset_ptr
->var
),
3380 locate
->slot_offset
.var
);
3382 /* Pad_below needs the pre-rounded size to know how much to pad
3384 locate
->offset
= locate
->slot_offset
;
3385 if (where_pad
== downward
)
3386 pad_below (&locate
->offset
, passed_mode
, sizetree
);
3388 #else /* !ARGS_GROW_DOWNWARD */
3390 #ifdef REG_PARM_STACK_SPACE
3391 || REG_PARM_STACK_SPACE (fndecl
) > 0
3394 pad_to_arg_alignment (initial_offset_ptr
, boundary
,
3395 &locate
->alignment_pad
);
3396 locate
->slot_offset
= *initial_offset_ptr
;
3398 #ifdef PUSH_ROUNDING
3399 if (passed_mode
!= BLKmode
)
3400 sizetree
= size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree
)));
3403 /* Pad_below needs the pre-rounded size to know how much to pad below
3404 so this must be done before rounding up. */
3405 locate
->offset
= locate
->slot_offset
;
3406 if (where_pad
== downward
)
3407 pad_below (&locate
->offset
, passed_mode
, sizetree
);
3409 if (where_pad
!= none
3410 && (!host_integerp (sizetree
, 1)
3411 || (tree_low_cst (sizetree
, 1) * BITS_PER_UNIT
) % PARM_BOUNDARY
))
3412 sizetree
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3414 ADD_PARM_SIZE (locate
->size
, sizetree
);
3416 locate
->size
.constant
-= part_size_in_regs
;
3417 #endif /* ARGS_GROW_DOWNWARD */
3420 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
3421 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
3424 pad_to_arg_alignment (struct args_size
*offset_ptr
, int boundary
,
3425 struct args_size
*alignment_pad
)
3427 tree save_var
= NULL_TREE
;
3428 HOST_WIDE_INT save_constant
= 0;
3429 int boundary_in_bytes
= boundary
/ BITS_PER_UNIT
;
3430 HOST_WIDE_INT sp_offset
= STACK_POINTER_OFFSET
;
3432 #ifdef SPARC_STACK_BOUNDARY_HACK
3433 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
3434 the real alignment of %sp. However, when it does this, the
3435 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
3436 if (SPARC_STACK_BOUNDARY_HACK
)
3440 if (boundary
> PARM_BOUNDARY
&& boundary
> STACK_BOUNDARY
)
3442 save_var
= offset_ptr
->var
;
3443 save_constant
= offset_ptr
->constant
;
3446 alignment_pad
->var
= NULL_TREE
;
3447 alignment_pad
->constant
= 0;
3449 if (boundary
> BITS_PER_UNIT
)
3451 if (offset_ptr
->var
)
3453 tree sp_offset_tree
= ssize_int (sp_offset
);
3454 tree offset
= size_binop (PLUS_EXPR
,
3455 ARGS_SIZE_TREE (*offset_ptr
),
3457 #ifdef ARGS_GROW_DOWNWARD
3458 tree rounded
= round_down (offset
, boundary
/ BITS_PER_UNIT
);
3460 tree rounded
= round_up (offset
, boundary
/ BITS_PER_UNIT
);
3463 offset_ptr
->var
= size_binop (MINUS_EXPR
, rounded
, sp_offset_tree
);
3464 /* ARGS_SIZE_TREE includes constant term. */
3465 offset_ptr
->constant
= 0;
3466 if (boundary
> PARM_BOUNDARY
&& boundary
> STACK_BOUNDARY
)
3467 alignment_pad
->var
= size_binop (MINUS_EXPR
, offset_ptr
->var
,
3472 offset_ptr
->constant
= -sp_offset
+
3473 #ifdef ARGS_GROW_DOWNWARD
3474 FLOOR_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
3476 CEIL_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
3478 if (boundary
> PARM_BOUNDARY
&& boundary
> STACK_BOUNDARY
)
3479 alignment_pad
->constant
= offset_ptr
->constant
- save_constant
;
3485 pad_below (struct args_size
*offset_ptr
, enum machine_mode passed_mode
, tree sizetree
)
3487 if (passed_mode
!= BLKmode
)
3489 if (GET_MODE_BITSIZE (passed_mode
) % PARM_BOUNDARY
)
3490 offset_ptr
->constant
3491 += (((GET_MODE_BITSIZE (passed_mode
) + PARM_BOUNDARY
- 1)
3492 / PARM_BOUNDARY
* PARM_BOUNDARY
/ BITS_PER_UNIT
)
3493 - GET_MODE_SIZE (passed_mode
));
3497 if (TREE_CODE (sizetree
) != INTEGER_CST
3498 || (TREE_INT_CST_LOW (sizetree
) * BITS_PER_UNIT
) % PARM_BOUNDARY
)
3500 /* Round the size up to multiple of PARM_BOUNDARY bits. */
3501 tree s2
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3503 ADD_PARM_SIZE (*offset_ptr
, s2
);
3504 SUB_PARM_SIZE (*offset_ptr
, sizetree
);
3509 /* Walk the tree of blocks describing the binding levels within a function
3510 and warn about variables the might be killed by setjmp or vfork.
3511 This is done after calling flow_analysis and before global_alloc
3512 clobbers the pseudo-regs to hard regs. */
3515 setjmp_vars_warning (tree block
)
3519 for (decl
= BLOCK_VARS (block
); decl
; decl
= TREE_CHAIN (decl
))
3521 if (TREE_CODE (decl
) == VAR_DECL
3522 && DECL_RTL_SET_P (decl
)
3523 && REG_P (DECL_RTL (decl
))
3524 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl
))))
3525 warning (OPT_Wclobbered
, "variable %q+D might be clobbered by"
3526 " %<longjmp%> or %<vfork%>", decl
);
3529 for (sub
= BLOCK_SUBBLOCKS (block
); sub
; sub
= TREE_CHAIN (sub
))
3530 setjmp_vars_warning (sub
);
3533 /* Do the appropriate part of setjmp_vars_warning
3534 but for arguments instead of local variables. */
3537 setjmp_args_warning (void)
3540 for (decl
= DECL_ARGUMENTS (current_function_decl
);
3541 decl
; decl
= TREE_CHAIN (decl
))
3542 if (DECL_RTL (decl
) != 0
3543 && REG_P (DECL_RTL (decl
))
3544 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl
))))
3545 warning (OPT_Wclobbered
,
3546 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
3551 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
3552 and create duplicate blocks. */
3553 /* ??? Need an option to either create block fragments or to create
3554 abstract origin duplicates of a source block. It really depends
3555 on what optimization has been performed. */
3558 reorder_blocks (void)
3560 tree block
= DECL_INITIAL (current_function_decl
);
3561 VEC(tree
,heap
) *block_stack
;
3563 if (block
== NULL_TREE
)
3566 block_stack
= VEC_alloc (tree
, heap
, 10);
3568 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
3569 clear_block_marks (block
);
3571 /* Prune the old trees away, so that they don't get in the way. */
3572 BLOCK_SUBBLOCKS (block
) = NULL_TREE
;
3573 BLOCK_CHAIN (block
) = NULL_TREE
;
3575 /* Recreate the block tree from the note nesting. */
3576 reorder_blocks_1 (get_insns (), block
, &block_stack
);
3577 BLOCK_SUBBLOCKS (block
) = blocks_nreverse (BLOCK_SUBBLOCKS (block
));
3579 VEC_free (tree
, heap
, block_stack
);
3582 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
3585 clear_block_marks (tree block
)
3589 TREE_ASM_WRITTEN (block
) = 0;
3590 clear_block_marks (BLOCK_SUBBLOCKS (block
));
3591 block
= BLOCK_CHAIN (block
);
3596 reorder_blocks_1 (rtx insns
, tree current_block
, VEC(tree
,heap
) **p_block_stack
)
3600 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
3604 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_BEG
)
3606 tree block
= NOTE_BLOCK (insn
);
3609 origin
= (BLOCK_FRAGMENT_ORIGIN (block
)
3610 ? BLOCK_FRAGMENT_ORIGIN (block
)
3613 /* If we have seen this block before, that means it now
3614 spans multiple address regions. Create a new fragment. */
3615 if (TREE_ASM_WRITTEN (block
))
3617 tree new_block
= copy_node (block
);
3619 BLOCK_FRAGMENT_ORIGIN (new_block
) = origin
;
3620 BLOCK_FRAGMENT_CHAIN (new_block
)
3621 = BLOCK_FRAGMENT_CHAIN (origin
);
3622 BLOCK_FRAGMENT_CHAIN (origin
) = new_block
;
3624 NOTE_BLOCK (insn
) = new_block
;
3628 BLOCK_SUBBLOCKS (block
) = 0;
3629 TREE_ASM_WRITTEN (block
) = 1;
3630 /* When there's only one block for the entire function,
3631 current_block == block and we mustn't do this, it
3632 will cause infinite recursion. */
3633 if (block
!= current_block
)
3635 if (block
!= origin
)
3636 gcc_assert (BLOCK_SUPERCONTEXT (origin
) == current_block
);
3638 BLOCK_SUPERCONTEXT (block
) = current_block
;
3639 BLOCK_CHAIN (block
) = BLOCK_SUBBLOCKS (current_block
);
3640 BLOCK_SUBBLOCKS (current_block
) = block
;
3641 current_block
= origin
;
3643 VEC_safe_push (tree
, heap
, *p_block_stack
, block
);
3645 else if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_END
)
3647 NOTE_BLOCK (insn
) = VEC_pop (tree
, *p_block_stack
);
3648 BLOCK_SUBBLOCKS (current_block
)
3649 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block
));
3650 current_block
= BLOCK_SUPERCONTEXT (current_block
);
3656 /* Reverse the order of elements in the chain T of blocks,
3657 and return the new head of the chain (old last element). */
3660 blocks_nreverse (tree t
)
3662 tree prev
= 0, decl
, next
;
3663 for (decl
= t
; decl
; decl
= next
)
3665 next
= BLOCK_CHAIN (decl
);
3666 BLOCK_CHAIN (decl
) = prev
;
3672 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
3673 non-NULL, list them all into VECTOR, in a depth-first preorder
3674 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
3678 all_blocks (tree block
, tree
*vector
)
3684 TREE_ASM_WRITTEN (block
) = 0;
3686 /* Record this block. */
3688 vector
[n_blocks
] = block
;
3692 /* Record the subblocks, and their subblocks... */
3693 n_blocks
+= all_blocks (BLOCK_SUBBLOCKS (block
),
3694 vector
? vector
+ n_blocks
: 0);
3695 block
= BLOCK_CHAIN (block
);
3701 /* Return a vector containing all the blocks rooted at BLOCK. The
3702 number of elements in the vector is stored in N_BLOCKS_P. The
3703 vector is dynamically allocated; it is the caller's responsibility
3704 to call `free' on the pointer returned. */
3707 get_block_vector (tree block
, int *n_blocks_p
)
3711 *n_blocks_p
= all_blocks (block
, NULL
);
3712 block_vector
= XNEWVEC (tree
, *n_blocks_p
);
3713 all_blocks (block
, block_vector
);
3715 return block_vector
;
3718 static GTY(()) int next_block_index
= 2;
3720 /* Set BLOCK_NUMBER for all the blocks in FN. */
3723 number_blocks (tree fn
)
3729 /* For SDB and XCOFF debugging output, we start numbering the blocks
3730 from 1 within each function, rather than keeping a running
3732 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
3733 if (write_symbols
== SDB_DEBUG
|| write_symbols
== XCOFF_DEBUG
)
3734 next_block_index
= 1;
3737 block_vector
= get_block_vector (DECL_INITIAL (fn
), &n_blocks
);
3739 /* The top-level BLOCK isn't numbered at all. */
3740 for (i
= 1; i
< n_blocks
; ++i
)
3741 /* We number the blocks from two. */
3742 BLOCK_NUMBER (block_vector
[i
]) = next_block_index
++;
3744 free (block_vector
);
3749 /* If VAR is present in a subblock of BLOCK, return the subblock. */
3752 debug_find_var_in_block_tree (tree var
, tree block
)
3756 for (t
= BLOCK_VARS (block
); t
; t
= TREE_CHAIN (t
))
3760 for (t
= BLOCK_SUBBLOCKS (block
); t
; t
= TREE_CHAIN (t
))
3762 tree ret
= debug_find_var_in_block_tree (var
, t
);
3771 /* Return value of funcdef and increase it. */
3773 get_next_funcdef_no (void)
3775 return funcdef_no
++;
3778 /* Allocate a function structure for FNDECL and set its contents
3782 allocate_struct_function (tree fndecl
)
3785 tree fntype
= fndecl
? TREE_TYPE (fndecl
) : NULL_TREE
;
3787 cfun
= ggc_alloc_cleared (sizeof (struct function
));
3789 cfun
->stack_alignment_needed
= STACK_BOUNDARY
;
3790 cfun
->preferred_stack_boundary
= STACK_BOUNDARY
;
3792 current_function_funcdef_no
= get_next_funcdef_no ();
3794 cfun
->function_frequency
= FUNCTION_FREQUENCY_NORMAL
;
3796 init_eh_for_function ();
3798 lang_hooks
.function
.init (cfun
);
3799 if (init_machine_status
)
3800 cfun
->machine
= (*init_machine_status
) ();
3805 DECL_STRUCT_FUNCTION (fndecl
) = cfun
;
3806 cfun
->decl
= fndecl
;
3808 result
= DECL_RESULT (fndecl
);
3809 if (aggregate_value_p (result
, fndecl
))
3811 #ifdef PCC_STATIC_STRUCT_RETURN
3812 current_function_returns_pcc_struct
= 1;
3814 current_function_returns_struct
= 1;
3817 current_function_returns_pointer
= POINTER_TYPE_P (TREE_TYPE (result
));
3819 current_function_stdarg
3821 && TYPE_ARG_TYPES (fntype
) != 0
3822 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype
)))
3823 != void_type_node
));
3825 /* Assume all registers in stdarg functions need to be saved. */
3826 cfun
->va_list_gpr_size
= VA_LIST_MAX_GPR_SIZE
;
3827 cfun
->va_list_fpr_size
= VA_LIST_MAX_FPR_SIZE
;
3830 /* Reset cfun, and other non-struct-function variables to defaults as
3831 appropriate for emitting rtl at the start of a function. */
3834 prepare_function_start (tree fndecl
)
3836 if (fndecl
&& DECL_STRUCT_FUNCTION (fndecl
))
3837 cfun
= DECL_STRUCT_FUNCTION (fndecl
);
3839 allocate_struct_function (fndecl
);
3841 init_varasm_status (cfun
);
3844 cse_not_expected
= ! optimize
;
3846 /* Caller save not needed yet. */
3847 caller_save_needed
= 0;
3849 /* We haven't done register allocation yet. */
3852 /* Indicate that we have not instantiated virtual registers yet. */
3853 virtuals_instantiated
= 0;
3855 /* Indicate that we want CONCATs now. */
3856 generating_concat_p
= 1;
3858 /* Indicate we have no need of a frame pointer yet. */
3859 frame_pointer_needed
= 0;
3862 /* Initialize the rtl expansion mechanism so that we can do simple things
3863 like generate sequences. This is used to provide a context during global
3864 initialization of some passes. */
3866 init_dummy_function_start (void)
3868 prepare_function_start (NULL
);
3871 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
3872 and initialize static variables for generating RTL for the statements
3876 init_function_start (tree subr
)
3878 prepare_function_start (subr
);
3880 /* Prevent ever trying to delete the first instruction of a
3881 function. Also tell final how to output a linenum before the
3882 function prologue. Note linenums could be missing, e.g. when
3883 compiling a Java .class file. */
3884 if (! DECL_IS_BUILTIN (subr
))
3885 emit_line_note (DECL_SOURCE_LOCATION (subr
));
3887 /* Make sure first insn is a note even if we don't want linenums.
3888 This makes sure the first insn will never be deleted.
3889 Also, final expects a note to appear there. */
3890 emit_note (NOTE_INSN_DELETED
);
3892 /* Warn if this value is an aggregate type,
3893 regardless of which calling convention we are using for it. */
3894 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr
))))
3895 warning (OPT_Waggregate_return
, "function returns an aggregate");
3898 /* Make sure all values used by the optimization passes have sane
3901 init_function_for_compilation (void)
3905 /* No prologue/epilogue insns yet. Make sure that these vectors are
3907 gcc_assert (VEC_length (int, prologue
) == 0);
3908 gcc_assert (VEC_length (int, epilogue
) == 0);
3909 gcc_assert (VEC_length (int, sibcall_epilogue
) == 0);
3913 struct tree_opt_pass pass_init_function
=
3917 init_function_for_compilation
, /* execute */
3920 0, /* static_pass_number */
3922 0, /* properties_required */
3923 0, /* properties_provided */
3924 0, /* properties_destroyed */
3925 0, /* todo_flags_start */
3926 0, /* todo_flags_finish */
3932 expand_main_function (void)
3934 #if (defined(INVOKE__main) \
3935 || (!defined(HAS_INIT_SECTION) \
3936 && !defined(INIT_SECTION_ASM_OP) \
3937 && !defined(INIT_ARRAY_SECTION_ASM_OP)))
3938 emit_library_call (init_one_libfunc (NAME__MAIN
), LCT_NORMAL
, VOIDmode
, 0);
3942 /* Expand code to initialize the stack_protect_guard. This is invoked at
3943 the beginning of a function to be protected. */
3945 #ifndef HAVE_stack_protect_set
3946 # define HAVE_stack_protect_set 0
3947 # define gen_stack_protect_set(x,y) (gcc_unreachable (), NULL_RTX)
3951 stack_protect_prologue (void)
3953 tree guard_decl
= targetm
.stack_protect_guard ();
3956 /* Avoid expand_expr here, because we don't want guard_decl pulled
3957 into registers unless absolutely necessary. And we know that
3958 cfun->stack_protect_guard is a local stack slot, so this skips
3960 x
= validize_mem (DECL_RTL (cfun
->stack_protect_guard
));
3961 y
= validize_mem (DECL_RTL (guard_decl
));
3963 /* Allow the target to copy from Y to X without leaking Y into a
3965 if (HAVE_stack_protect_set
)
3967 rtx insn
= gen_stack_protect_set (x
, y
);
3975 /* Otherwise do a straight move. */
3976 emit_move_insn (x
, y
);
3979 /* Expand code to verify the stack_protect_guard. This is invoked at
3980 the end of a function to be protected. */
3982 #ifndef HAVE_stack_protect_test
3983 # define HAVE_stack_protect_test 0
3984 # define gen_stack_protect_test(x, y, z) (gcc_unreachable (), NULL_RTX)
3988 stack_protect_epilogue (void)
3990 tree guard_decl
= targetm
.stack_protect_guard ();
3991 rtx label
= gen_label_rtx ();
3994 /* Avoid expand_expr here, because we don't want guard_decl pulled
3995 into registers unless absolutely necessary. And we know that
3996 cfun->stack_protect_guard is a local stack slot, so this skips
3998 x
= validize_mem (DECL_RTL (cfun
->stack_protect_guard
));
3999 y
= validize_mem (DECL_RTL (guard_decl
));
4001 /* Allow the target to compare Y with X without leaking either into
4003 switch (HAVE_stack_protect_test
!= 0)
4006 tmp
= gen_stack_protect_test (x
, y
, label
);
4015 emit_cmp_and_jump_insns (x
, y
, EQ
, NULL_RTX
, ptr_mode
, 1, label
);
4019 /* The noreturn predictor has been moved to the tree level. The rtl-level
4020 predictors estimate this branch about 20%, which isn't enough to get
4021 things moved out of line. Since this is the only extant case of adding
4022 a noreturn function at the rtl level, it doesn't seem worth doing ought
4023 except adding the prediction by hand. */
4024 tmp
= get_last_insn ();
4026 predict_insn_def (tmp
, PRED_NORETURN
, TAKEN
);
4028 expand_expr_stmt (targetm
.stack_protect_fail ());
4032 /* Start the RTL for a new function, and set variables used for
4034 SUBR is the FUNCTION_DECL node.
4035 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4036 the function's parameters, which must be run at any return statement. */
4039 expand_function_start (tree subr
)
4041 /* Make sure volatile mem refs aren't considered
4042 valid operands of arithmetic insns. */
4043 init_recog_no_volatile ();
4045 current_function_profile
4047 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr
));
4049 current_function_limit_stack
4050 = (stack_limit_rtx
!= NULL_RTX
&& ! DECL_NO_LIMIT_STACK (subr
));
4052 /* Make the label for return statements to jump to. Do not special
4053 case machines with special return instructions -- they will be
4054 handled later during jump, ifcvt, or epilogue creation. */
4055 return_label
= gen_label_rtx ();
4057 /* Initialize rtx used to return the value. */
4058 /* Do this before assign_parms so that we copy the struct value address
4059 before any library calls that assign parms might generate. */
4061 /* Decide whether to return the value in memory or in a register. */
4062 if (aggregate_value_p (DECL_RESULT (subr
), subr
))
4064 /* Returning something that won't go in a register. */
4065 rtx value_address
= 0;
4067 #ifdef PCC_STATIC_STRUCT_RETURN
4068 if (current_function_returns_pcc_struct
)
4070 int size
= int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr
)));
4071 value_address
= assemble_static_space (size
);
4076 rtx sv
= targetm
.calls
.struct_value_rtx (TREE_TYPE (subr
), 2);
4077 /* Expect to be passed the address of a place to store the value.
4078 If it is passed as an argument, assign_parms will take care of
4082 value_address
= gen_reg_rtx (Pmode
);
4083 emit_move_insn (value_address
, sv
);
4088 rtx x
= value_address
;
4089 if (!DECL_BY_REFERENCE (DECL_RESULT (subr
)))
4091 x
= gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr
)), x
);
4092 set_mem_attributes (x
, DECL_RESULT (subr
), 1);
4094 SET_DECL_RTL (DECL_RESULT (subr
), x
);
4097 else if (DECL_MODE (DECL_RESULT (subr
)) == VOIDmode
)
4098 /* If return mode is void, this decl rtl should not be used. */
4099 SET_DECL_RTL (DECL_RESULT (subr
), NULL_RTX
);
4102 /* Compute the return values into a pseudo reg, which we will copy
4103 into the true return register after the cleanups are done. */
4104 tree return_type
= TREE_TYPE (DECL_RESULT (subr
));
4105 if (TYPE_MODE (return_type
) != BLKmode
4106 && targetm
.calls
.return_in_msb (return_type
))
4107 /* expand_function_end will insert the appropriate padding in
4108 this case. Use the return value's natural (unpadded) mode
4109 within the function proper. */
4110 SET_DECL_RTL (DECL_RESULT (subr
),
4111 gen_reg_rtx (TYPE_MODE (return_type
)));
4114 /* In order to figure out what mode to use for the pseudo, we
4115 figure out what the mode of the eventual return register will
4116 actually be, and use that. */
4117 rtx hard_reg
= hard_function_value (return_type
, subr
, 0, 1);
4119 /* Structures that are returned in registers are not
4120 aggregate_value_p, so we may see a PARALLEL or a REG. */
4121 if (REG_P (hard_reg
))
4122 SET_DECL_RTL (DECL_RESULT (subr
),
4123 gen_reg_rtx (GET_MODE (hard_reg
)));
4126 gcc_assert (GET_CODE (hard_reg
) == PARALLEL
);
4127 SET_DECL_RTL (DECL_RESULT (subr
), gen_group_rtx (hard_reg
));
4131 /* Set DECL_REGISTER flag so that expand_function_end will copy the
4132 result to the real return register(s). */
4133 DECL_REGISTER (DECL_RESULT (subr
)) = 1;
4136 /* Initialize rtx for parameters and local variables.
4137 In some cases this requires emitting insns. */
4138 assign_parms (subr
);
4140 /* If function gets a static chain arg, store it. */
4141 if (cfun
->static_chain_decl
)
4143 tree parm
= cfun
->static_chain_decl
;
4144 rtx local
= gen_reg_rtx (Pmode
);
4146 set_decl_incoming_rtl (parm
, static_chain_incoming_rtx
);
4147 SET_DECL_RTL (parm
, local
);
4148 mark_reg_pointer (local
, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
4150 emit_move_insn (local
, static_chain_incoming_rtx
);
4153 /* If the function receives a non-local goto, then store the
4154 bits we need to restore the frame pointer. */
4155 if (cfun
->nonlocal_goto_save_area
)
4160 /* ??? We need to do this save early. Unfortunately here is
4161 before the frame variable gets declared. Help out... */
4162 expand_var (TREE_OPERAND (cfun
->nonlocal_goto_save_area
, 0));
4164 t_save
= build4 (ARRAY_REF
, ptr_type_node
,
4165 cfun
->nonlocal_goto_save_area
,
4166 integer_zero_node
, NULL_TREE
, NULL_TREE
);
4167 r_save
= expand_expr (t_save
, NULL_RTX
, VOIDmode
, EXPAND_WRITE
);
4168 r_save
= convert_memory_address (Pmode
, r_save
);
4170 emit_move_insn (r_save
, virtual_stack_vars_rtx
);
4171 update_nonlocal_goto_save_area ();
4174 /* The following was moved from init_function_start.
4175 The move is supposed to make sdb output more accurate. */
4176 /* Indicate the beginning of the function body,
4177 as opposed to parm setup. */
4178 emit_note (NOTE_INSN_FUNCTION_BEG
);
4180 gcc_assert (NOTE_P (get_last_insn ()));
4182 parm_birth_insn
= get_last_insn ();
4184 if (current_function_profile
)
4187 PROFILE_HOOK (current_function_funcdef_no
);
4191 /* After the display initializations is where the stack checking
4193 if(flag_stack_check
)
4194 stack_check_probe_note
= emit_note (NOTE_INSN_DELETED
);
4196 /* Make sure there is a line number after the function entry setup code. */
4197 force_next_line_note ();
4200 /* Undo the effects of init_dummy_function_start. */
4202 expand_dummy_function_end (void)
4204 /* End any sequences that failed to be closed due to syntax errors. */
4205 while (in_sequence_p ())
4208 /* Outside function body, can't compute type's actual size
4209 until next function's body starts. */
4211 free_after_parsing (cfun
);
4212 free_after_compilation (cfun
);
4216 /* Call DOIT for each hard register used as a return value from
4217 the current function. */
4220 diddle_return_value (void (*doit
) (rtx
, void *), void *arg
)
4222 rtx outgoing
= current_function_return_rtx
;
4227 if (REG_P (outgoing
))
4228 (*doit
) (outgoing
, arg
);
4229 else if (GET_CODE (outgoing
) == PARALLEL
)
4233 for (i
= 0; i
< XVECLEN (outgoing
, 0); i
++)
4235 rtx x
= XEXP (XVECEXP (outgoing
, 0, i
), 0);
4237 if (REG_P (x
) && REGNO (x
) < FIRST_PSEUDO_REGISTER
)
4244 do_clobber_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
4246 emit_insn (gen_rtx_CLOBBER (VOIDmode
, reg
));
4250 clobber_return_register (void)
4252 diddle_return_value (do_clobber_return_reg
, NULL
);
4254 /* In case we do use pseudo to return value, clobber it too. */
4255 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
4257 tree decl_result
= DECL_RESULT (current_function_decl
);
4258 rtx decl_rtl
= DECL_RTL (decl_result
);
4259 if (REG_P (decl_rtl
) && REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
)
4261 do_clobber_return_reg (decl_rtl
, NULL
);
4267 do_use_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
4269 emit_insn (gen_rtx_USE (VOIDmode
, reg
));
4273 use_return_register (void)
4275 diddle_return_value (do_use_return_reg
, NULL
);
4278 /* Possibly warn about unused parameters. */
4280 do_warn_unused_parameter (tree fn
)
4284 for (decl
= DECL_ARGUMENTS (fn
);
4285 decl
; decl
= TREE_CHAIN (decl
))
4286 if (!TREE_USED (decl
) && TREE_CODE (decl
) == PARM_DECL
4287 && DECL_NAME (decl
) && !DECL_ARTIFICIAL (decl
))
4288 warning (OPT_Wunused_parameter
, "unused parameter %q+D", decl
);
4291 static GTY(()) rtx initial_trampoline
;
4293 /* Generate RTL for the end of the current function. */
4296 expand_function_end (void)
4300 /* If arg_pointer_save_area was referenced only from a nested
4301 function, we will not have initialized it yet. Do that now. */
4302 if (arg_pointer_save_area
&& ! cfun
->arg_pointer_save_area_init
)
4303 get_arg_pointer_save_area (cfun
);
4305 /* If we are doing stack checking and this function makes calls,
4306 do a stack probe at the start of the function to ensure we have enough
4307 space for another stack frame. */
4308 if (flag_stack_check
&& ! STACK_CHECK_BUILTIN
)
4312 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
4316 probe_stack_range (STACK_CHECK_PROTECT
,
4317 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE
));
4320 emit_insn_before (seq
, stack_check_probe_note
);
4325 /* Possibly warn about unused parameters.
4326 When frontend does unit-at-a-time, the warning is already
4327 issued at finalization time. */
4328 if (warn_unused_parameter
4329 && !lang_hooks
.callgraph
.expand_function
)
4330 do_warn_unused_parameter (current_function_decl
);
4332 /* End any sequences that failed to be closed due to syntax errors. */
4333 while (in_sequence_p ())
4336 clear_pending_stack_adjust ();
4337 do_pending_stack_adjust ();
4339 /* Output a linenumber for the end of the function.
4340 SDB depends on this. */
4341 force_next_line_note ();
4342 emit_line_note (input_location
);
4344 /* Before the return label (if any), clobber the return
4345 registers so that they are not propagated live to the rest of
4346 the function. This can only happen with functions that drop
4347 through; if there had been a return statement, there would
4348 have either been a return rtx, or a jump to the return label.
4350 We delay actual code generation after the current_function_value_rtx
4352 clobber_after
= get_last_insn ();
4354 /* Output the label for the actual return from the function. */
4355 emit_label (return_label
);
4357 if (USING_SJLJ_EXCEPTIONS
)
4359 /* Let except.c know where it should emit the call to unregister
4360 the function context for sjlj exceptions. */
4361 if (flag_exceptions
)
4362 sjlj_emit_function_exit_after (get_last_insn ());
4366 /* @@@ This is a kludge. We want to ensure that instructions that
4367 may trap are not moved into the epilogue by scheduling, because
4368 we don't always emit unwind information for the epilogue.
4369 However, not all machine descriptions define a blockage insn, so
4370 emit an ASM_INPUT to act as one. */
4371 if (flag_non_call_exceptions
)
4372 emit_insn (gen_rtx_ASM_INPUT (VOIDmode
, ""));
4375 /* If this is an implementation of throw, do what's necessary to
4376 communicate between __builtin_eh_return and the epilogue. */
4377 expand_eh_return ();
4379 /* If scalar return value was computed in a pseudo-reg, or was a named
4380 return value that got dumped to the stack, copy that to the hard
4382 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
4384 tree decl_result
= DECL_RESULT (current_function_decl
);
4385 rtx decl_rtl
= DECL_RTL (decl_result
);
4387 if (REG_P (decl_rtl
)
4388 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
4389 : DECL_REGISTER (decl_result
))
4391 rtx real_decl_rtl
= current_function_return_rtx
;
4393 /* This should be set in assign_parms. */
4394 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl
));
4396 /* If this is a BLKmode structure being returned in registers,
4397 then use the mode computed in expand_return. Note that if
4398 decl_rtl is memory, then its mode may have been changed,
4399 but that current_function_return_rtx has not. */
4400 if (GET_MODE (real_decl_rtl
) == BLKmode
)
4401 PUT_MODE (real_decl_rtl
, GET_MODE (decl_rtl
));
4403 /* If a non-BLKmode return value should be padded at the least
4404 significant end of the register, shift it left by the appropriate
4405 amount. BLKmode results are handled using the group load/store
4407 if (TYPE_MODE (TREE_TYPE (decl_result
)) != BLKmode
4408 && targetm
.calls
.return_in_msb (TREE_TYPE (decl_result
)))
4410 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl
),
4411 REGNO (real_decl_rtl
)),
4413 shift_return_value (GET_MODE (decl_rtl
), true, real_decl_rtl
);
4415 /* If a named return value dumped decl_return to memory, then
4416 we may need to re-do the PROMOTE_MODE signed/unsigned
4418 else if (GET_MODE (real_decl_rtl
) != GET_MODE (decl_rtl
))
4420 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (decl_result
));
4422 if (targetm
.calls
.promote_function_return (TREE_TYPE (current_function_decl
)))
4423 promote_mode (TREE_TYPE (decl_result
), GET_MODE (decl_rtl
),
4426 convert_move (real_decl_rtl
, decl_rtl
, unsignedp
);
4428 else if (GET_CODE (real_decl_rtl
) == PARALLEL
)
4430 /* If expand_function_start has created a PARALLEL for decl_rtl,
4431 move the result to the real return registers. Otherwise, do
4432 a group load from decl_rtl for a named return. */
4433 if (GET_CODE (decl_rtl
) == PARALLEL
)
4434 emit_group_move (real_decl_rtl
, decl_rtl
);
4436 emit_group_load (real_decl_rtl
, decl_rtl
,
4437 TREE_TYPE (decl_result
),
4438 int_size_in_bytes (TREE_TYPE (decl_result
)));
4440 /* In the case of complex integer modes smaller than a word, we'll
4441 need to generate some non-trivial bitfield insertions. Do that
4442 on a pseudo and not the hard register. */
4443 else if (GET_CODE (decl_rtl
) == CONCAT
4444 && GET_MODE_CLASS (GET_MODE (decl_rtl
)) == MODE_COMPLEX_INT
4445 && GET_MODE_BITSIZE (GET_MODE (decl_rtl
)) <= BITS_PER_WORD
)
4447 int old_generating_concat_p
;
4450 old_generating_concat_p
= generating_concat_p
;
4451 generating_concat_p
= 0;
4452 tmp
= gen_reg_rtx (GET_MODE (decl_rtl
));
4453 generating_concat_p
= old_generating_concat_p
;
4455 emit_move_insn (tmp
, decl_rtl
);
4456 emit_move_insn (real_decl_rtl
, tmp
);
4459 emit_move_insn (real_decl_rtl
, decl_rtl
);
4463 /* If returning a structure, arrange to return the address of the value
4464 in a place where debuggers expect to find it.
4466 If returning a structure PCC style,
4467 the caller also depends on this value.
4468 And current_function_returns_pcc_struct is not necessarily set. */
4469 if (current_function_returns_struct
4470 || current_function_returns_pcc_struct
)
4472 rtx value_address
= DECL_RTL (DECL_RESULT (current_function_decl
));
4473 tree type
= TREE_TYPE (DECL_RESULT (current_function_decl
));
4476 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl
)))
4477 type
= TREE_TYPE (type
);
4479 value_address
= XEXP (value_address
, 0);
4481 outgoing
= targetm
.calls
.function_value (build_pointer_type (type
),
4482 current_function_decl
, true);
4484 /* Mark this as a function return value so integrate will delete the
4485 assignment and USE below when inlining this function. */
4486 REG_FUNCTION_VALUE_P (outgoing
) = 1;
4488 /* The address may be ptr_mode and OUTGOING may be Pmode. */
4489 value_address
= convert_memory_address (GET_MODE (outgoing
),
4492 emit_move_insn (outgoing
, value_address
);
4494 /* Show return register used to hold result (in this case the address
4496 current_function_return_rtx
= outgoing
;
4499 /* Emit the actual code to clobber return register. */
4504 clobber_return_register ();
4505 expand_naked_return ();
4509 emit_insn_after (seq
, clobber_after
);
4512 /* Output the label for the naked return from the function. */
4513 emit_label (naked_return_label
);
4515 /* If stack protection is enabled for this function, check the guard. */
4516 if (cfun
->stack_protect_guard
)
4517 stack_protect_epilogue ();
4519 /* If we had calls to alloca, and this machine needs
4520 an accurate stack pointer to exit the function,
4521 insert some code to save and restore the stack pointer. */
4522 if (! EXIT_IGNORE_STACK
4523 && current_function_calls_alloca
)
4527 emit_stack_save (SAVE_FUNCTION
, &tem
, parm_birth_insn
);
4528 emit_stack_restore (SAVE_FUNCTION
, tem
, NULL_RTX
);
4531 /* ??? This should no longer be necessary since stupid is no longer with
4532 us, but there are some parts of the compiler (eg reload_combine, and
4533 sh mach_dep_reorg) that still try and compute their own lifetime info
4534 instead of using the general framework. */
4535 use_return_register ();
4539 get_arg_pointer_save_area (struct function
*f
)
4541 rtx ret
= f
->x_arg_pointer_save_area
;
4545 ret
= assign_stack_local_1 (Pmode
, GET_MODE_SIZE (Pmode
), 0, f
);
4546 f
->x_arg_pointer_save_area
= ret
;
4549 if (f
== cfun
&& ! f
->arg_pointer_save_area_init
)
4553 /* Save the arg pointer at the beginning of the function. The
4554 generated stack slot may not be a valid memory address, so we
4555 have to check it and fix it if necessary. */
4557 emit_move_insn (validize_mem (ret
), virtual_incoming_args_rtx
);
4561 push_topmost_sequence ();
4562 emit_insn_after (seq
, entry_of_function ());
4563 pop_topmost_sequence ();
4569 /* Extend a vector that records the INSN_UIDs of INSNS
4570 (a list of one or more insns). */
4573 record_insns (rtx insns
, VEC(int,heap
) **vecp
)
4577 for (tmp
= insns
; tmp
!= NULL_RTX
; tmp
= NEXT_INSN (tmp
))
4578 VEC_safe_push (int, heap
, *vecp
, INSN_UID (tmp
));
4581 /* Set the locator of the insn chain starting at INSN to LOC. */
4583 set_insn_locators (rtx insn
, int loc
)
4585 while (insn
!= NULL_RTX
)
4588 INSN_LOCATOR (insn
) = loc
;
4589 insn
= NEXT_INSN (insn
);
4593 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
4594 be running after reorg, SEQUENCE rtl is possible. */
4597 contains (rtx insn
, VEC(int,heap
) **vec
)
4601 if (NONJUMP_INSN_P (insn
)
4602 && GET_CODE (PATTERN (insn
)) == SEQUENCE
)
4605 for (i
= XVECLEN (PATTERN (insn
), 0) - 1; i
>= 0; i
--)
4606 for (j
= VEC_length (int, *vec
) - 1; j
>= 0; --j
)
4607 if (INSN_UID (XVECEXP (PATTERN (insn
), 0, i
))
4608 == VEC_index (int, *vec
, j
))
4614 for (j
= VEC_length (int, *vec
) - 1; j
>= 0; --j
)
4615 if (INSN_UID (insn
) == VEC_index (int, *vec
, j
))
4622 prologue_epilogue_contains (rtx insn
)
4624 if (contains (insn
, &prologue
))
4626 if (contains (insn
, &epilogue
))
4632 sibcall_epilogue_contains (rtx insn
)
4634 if (sibcall_epilogue
)
4635 return contains (insn
, &sibcall_epilogue
);
4640 /* Insert gen_return at the end of block BB. This also means updating
4641 block_for_insn appropriately. */
4644 emit_return_into_block (basic_block bb
)
4646 emit_jump_insn_after (gen_return (), BB_END (bb
));
4648 #endif /* HAVE_return */
4650 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
4652 /* These functions convert the epilogue into a variant that does not
4653 modify the stack pointer. This is used in cases where a function
4654 returns an object whose size is not known until it is computed.
4655 The called function leaves the object on the stack, leaves the
4656 stack depressed, and returns a pointer to the object.
4658 What we need to do is track all modifications and references to the
4659 stack pointer, deleting the modifications and changing the
4660 references to point to the location the stack pointer would have
4661 pointed to had the modifications taken place.
4663 These functions need to be portable so we need to make as few
4664 assumptions about the epilogue as we can. However, the epilogue
4665 basically contains three things: instructions to reset the stack
4666 pointer, instructions to reload registers, possibly including the
4667 frame pointer, and an instruction to return to the caller.
4669 We must be sure of what a relevant epilogue insn is doing. We also
4670 make no attempt to validate the insns we make since if they are
4671 invalid, we probably can't do anything valid. The intent is that
4672 these routines get "smarter" as more and more machines start to use
4673 them and they try operating on different epilogues.
4675 We use the following structure to track what the part of the
4676 epilogue that we've already processed has done. We keep two copies
4677 of the SP equivalence, one for use during the insn we are
4678 processing and one for use in the next insn. The difference is
4679 because one part of a PARALLEL may adjust SP and the other may use
4684 rtx sp_equiv_reg
; /* REG that SP is set from, perhaps SP. */
4685 HOST_WIDE_INT sp_offset
; /* Offset from SP_EQUIV_REG of present SP. */
4686 rtx new_sp_equiv_reg
; /* REG to be used at end of insn. */
4687 HOST_WIDE_INT new_sp_offset
; /* Offset to be used at end of insn. */
4688 rtx equiv_reg_src
; /* If nonzero, the value that SP_EQUIV_REG
4689 should be set to once we no longer need
4691 rtx const_equiv
[FIRST_PSEUDO_REGISTER
]; /* Any known constant equivalences
4695 static void handle_epilogue_set (rtx
, struct epi_info
*);
4696 static void update_epilogue_consts (rtx
, rtx
, void *);
4697 static void emit_equiv_load (struct epi_info
*);
4699 /* Modify INSN, a list of one or more insns that is part of the epilogue, to
4700 no modifications to the stack pointer. Return the new list of insns. */
4703 keep_stack_depressed (rtx insns
)
4706 struct epi_info info
;
4709 /* If the epilogue is just a single instruction, it must be OK as is. */
4710 if (NEXT_INSN (insns
) == NULL_RTX
)
4713 /* Otherwise, start a sequence, initialize the information we have, and
4714 process all the insns we were given. */
4717 info
.sp_equiv_reg
= stack_pointer_rtx
;
4719 info
.equiv_reg_src
= 0;
4721 for (j
= 0; j
< FIRST_PSEUDO_REGISTER
; j
++)
4722 info
.const_equiv
[j
] = 0;
4726 while (insn
!= NULL_RTX
)
4728 next
= NEXT_INSN (insn
);
4737 /* If this insn references the register that SP is equivalent to and
4738 we have a pending load to that register, we must force out the load
4739 first and then indicate we no longer know what SP's equivalent is. */
4740 if (info
.equiv_reg_src
!= 0
4741 && reg_referenced_p (info
.sp_equiv_reg
, PATTERN (insn
)))
4743 emit_equiv_load (&info
);
4744 info
.sp_equiv_reg
= 0;
4747 info
.new_sp_equiv_reg
= info
.sp_equiv_reg
;
4748 info
.new_sp_offset
= info
.sp_offset
;
4750 /* If this is a (RETURN) and the return address is on the stack,
4751 update the address and change to an indirect jump. */
4752 if (GET_CODE (PATTERN (insn
)) == RETURN
4753 || (GET_CODE (PATTERN (insn
)) == PARALLEL
4754 && GET_CODE (XVECEXP (PATTERN (insn
), 0, 0)) == RETURN
))
4756 rtx retaddr
= INCOMING_RETURN_ADDR_RTX
;
4758 HOST_WIDE_INT offset
= 0;
4759 rtx jump_insn
, jump_set
;
4761 /* If the return address is in a register, we can emit the insn
4762 unchanged. Otherwise, it must be a MEM and we see what the
4763 base register and offset are. In any case, we have to emit any
4764 pending load to the equivalent reg of SP, if any. */
4765 if (REG_P (retaddr
))
4767 emit_equiv_load (&info
);
4775 gcc_assert (MEM_P (retaddr
));
4777 ret_ptr
= XEXP (retaddr
, 0);
4779 if (REG_P (ret_ptr
))
4781 base
= gen_rtx_REG (Pmode
, REGNO (ret_ptr
));
4786 gcc_assert (GET_CODE (ret_ptr
) == PLUS
4787 && REG_P (XEXP (ret_ptr
, 0))
4788 && GET_CODE (XEXP (ret_ptr
, 1)) == CONST_INT
);
4789 base
= gen_rtx_REG (Pmode
, REGNO (XEXP (ret_ptr
, 0)));
4790 offset
= INTVAL (XEXP (ret_ptr
, 1));
4794 /* If the base of the location containing the return pointer
4795 is SP, we must update it with the replacement address. Otherwise,
4796 just build the necessary MEM. */
4797 retaddr
= plus_constant (base
, offset
);
4798 if (base
== stack_pointer_rtx
)
4799 retaddr
= simplify_replace_rtx (retaddr
, stack_pointer_rtx
,
4800 plus_constant (info
.sp_equiv_reg
,
4803 retaddr
= gen_rtx_MEM (Pmode
, retaddr
);
4804 MEM_NOTRAP_P (retaddr
) = 1;
4806 /* If there is a pending load to the equivalent register for SP
4807 and we reference that register, we must load our address into
4808 a scratch register and then do that load. */
4809 if (info
.equiv_reg_src
4810 && reg_overlap_mentioned_p (info
.equiv_reg_src
, retaddr
))
4815 for (regno
= 0; regno
< FIRST_PSEUDO_REGISTER
; regno
++)
4816 if (HARD_REGNO_MODE_OK (regno
, Pmode
)
4817 && !fixed_regs
[regno
]
4818 && TEST_HARD_REG_BIT (regs_invalidated_by_call
, regno
)
4820 (EXIT_BLOCK_PTR
->il
.rtl
->global_live_at_start
, regno
)
4821 && !refers_to_regno_p (regno
,
4822 regno
+ hard_regno_nregs
[regno
]
4824 info
.equiv_reg_src
, NULL
)
4825 && info
.const_equiv
[regno
] == 0)
4828 gcc_assert (regno
< FIRST_PSEUDO_REGISTER
);
4830 reg
= gen_rtx_REG (Pmode
, regno
);
4831 emit_move_insn (reg
, retaddr
);
4835 emit_equiv_load (&info
);
4836 jump_insn
= emit_jump_insn (gen_indirect_jump (retaddr
));
4838 /* Show the SET in the above insn is a RETURN. */
4839 jump_set
= single_set (jump_insn
);
4840 gcc_assert (jump_set
);
4841 SET_IS_RETURN_P (jump_set
) = 1;
4844 /* If SP is not mentioned in the pattern and its equivalent register, if
4845 any, is not modified, just emit it. Otherwise, if neither is set,
4846 replace the reference to SP and emit the insn. If none of those are
4847 true, handle each SET individually. */
4848 else if (!reg_mentioned_p (stack_pointer_rtx
, PATTERN (insn
))
4849 && (info
.sp_equiv_reg
== stack_pointer_rtx
4850 || !reg_set_p (info
.sp_equiv_reg
, insn
)))
4852 else if (! reg_set_p (stack_pointer_rtx
, insn
)
4853 && (info
.sp_equiv_reg
== stack_pointer_rtx
4854 || !reg_set_p (info
.sp_equiv_reg
, insn
)))
4858 changed
= validate_replace_rtx (stack_pointer_rtx
,
4859 plus_constant (info
.sp_equiv_reg
,
4862 gcc_assert (changed
);
4866 else if (GET_CODE (PATTERN (insn
)) == SET
)
4867 handle_epilogue_set (PATTERN (insn
), &info
);
4868 else if (GET_CODE (PATTERN (insn
)) == PARALLEL
)
4870 for (j
= 0; j
< XVECLEN (PATTERN (insn
), 0); j
++)
4871 if (GET_CODE (XVECEXP (PATTERN (insn
), 0, j
)) == SET
)
4872 handle_epilogue_set (XVECEXP (PATTERN (insn
), 0, j
), &info
);
4877 info
.sp_equiv_reg
= info
.new_sp_equiv_reg
;
4878 info
.sp_offset
= info
.new_sp_offset
;
4880 /* Now update any constants this insn sets. */
4881 note_stores (PATTERN (insn
), update_epilogue_consts
, &info
);
4885 insns
= get_insns ();
4890 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
4891 structure that contains information about what we've seen so far. We
4892 process this SET by either updating that data or by emitting one or
4896 handle_epilogue_set (rtx set
, struct epi_info
*p
)
4898 /* First handle the case where we are setting SP. Record what it is being
4899 set from, which we must be able to determine */
4900 if (reg_set_p (stack_pointer_rtx
, set
))
4902 gcc_assert (SET_DEST (set
) == stack_pointer_rtx
);
4904 if (GET_CODE (SET_SRC (set
)) == PLUS
)
4906 p
->new_sp_equiv_reg
= XEXP (SET_SRC (set
), 0);
4907 if (GET_CODE (XEXP (SET_SRC (set
), 1)) == CONST_INT
)
4908 p
->new_sp_offset
= INTVAL (XEXP (SET_SRC (set
), 1));
4911 gcc_assert (REG_P (XEXP (SET_SRC (set
), 1))
4912 && (REGNO (XEXP (SET_SRC (set
), 1))
4913 < FIRST_PSEUDO_REGISTER
)
4914 && p
->const_equiv
[REGNO (XEXP (SET_SRC (set
), 1))]);
4916 = INTVAL (p
->const_equiv
[REGNO (XEXP (SET_SRC (set
), 1))]);
4920 p
->new_sp_equiv_reg
= SET_SRC (set
), p
->new_sp_offset
= 0;
4922 /* If we are adjusting SP, we adjust from the old data. */
4923 if (p
->new_sp_equiv_reg
== stack_pointer_rtx
)
4925 p
->new_sp_equiv_reg
= p
->sp_equiv_reg
;
4926 p
->new_sp_offset
+= p
->sp_offset
;
4929 gcc_assert (p
->new_sp_equiv_reg
&& REG_P (p
->new_sp_equiv_reg
));
4934 /* Next handle the case where we are setting SP's equivalent
4935 register. We must not already have a value to set it to. We
4936 could update, but there seems little point in handling that case.
4937 Note that we have to allow for the case where we are setting the
4938 register set in the previous part of a PARALLEL inside a single
4939 insn. But use the old offset for any updates within this insn.
4940 We must allow for the case where the register is being set in a
4941 different (usually wider) mode than Pmode). */
4942 else if (p
->new_sp_equiv_reg
!= 0 && reg_set_p (p
->new_sp_equiv_reg
, set
))
4944 gcc_assert (!p
->equiv_reg_src
4945 && REG_P (p
->new_sp_equiv_reg
)
4946 && REG_P (SET_DEST (set
))
4947 && (GET_MODE_BITSIZE (GET_MODE (SET_DEST (set
)))
4949 && REGNO (p
->new_sp_equiv_reg
) == REGNO (SET_DEST (set
)));
4951 = simplify_replace_rtx (SET_SRC (set
), stack_pointer_rtx
,
4952 plus_constant (p
->sp_equiv_reg
,
4956 /* Otherwise, replace any references to SP in the insn to its new value
4957 and emit the insn. */
4960 SET_SRC (set
) = simplify_replace_rtx (SET_SRC (set
), stack_pointer_rtx
,
4961 plus_constant (p
->sp_equiv_reg
,
4963 SET_DEST (set
) = simplify_replace_rtx (SET_DEST (set
), stack_pointer_rtx
,
4964 plus_constant (p
->sp_equiv_reg
,
4970 /* Update the tracking information for registers set to constants. */
4973 update_epilogue_consts (rtx dest
, rtx x
, void *data
)
4975 struct epi_info
*p
= (struct epi_info
*) data
;
4978 if (!REG_P (dest
) || REGNO (dest
) >= FIRST_PSEUDO_REGISTER
)
4981 /* If we are either clobbering a register or doing a partial set,
4982 show we don't know the value. */
4983 else if (GET_CODE (x
) == CLOBBER
|| ! rtx_equal_p (dest
, SET_DEST (x
)))
4984 p
->const_equiv
[REGNO (dest
)] = 0;
4986 /* If we are setting it to a constant, record that constant. */
4987 else if (GET_CODE (SET_SRC (x
)) == CONST_INT
)
4988 p
->const_equiv
[REGNO (dest
)] = SET_SRC (x
);
4990 /* If this is a binary operation between a register we have been tracking
4991 and a constant, see if we can compute a new constant value. */
4992 else if (ARITHMETIC_P (SET_SRC (x
))
4993 && REG_P (XEXP (SET_SRC (x
), 0))
4994 && REGNO (XEXP (SET_SRC (x
), 0)) < FIRST_PSEUDO_REGISTER
4995 && p
->const_equiv
[REGNO (XEXP (SET_SRC (x
), 0))] != 0
4996 && GET_CODE (XEXP (SET_SRC (x
), 1)) == CONST_INT
4997 && 0 != (new = simplify_binary_operation
4998 (GET_CODE (SET_SRC (x
)), GET_MODE (dest
),
4999 p
->const_equiv
[REGNO (XEXP (SET_SRC (x
), 0))],
5000 XEXP (SET_SRC (x
), 1)))
5001 && GET_CODE (new) == CONST_INT
)
5002 p
->const_equiv
[REGNO (dest
)] = new;
5004 /* Otherwise, we can't do anything with this value. */
5006 p
->const_equiv
[REGNO (dest
)] = 0;
5009 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
5012 emit_equiv_load (struct epi_info
*p
)
5014 if (p
->equiv_reg_src
!= 0)
5016 rtx dest
= p
->sp_equiv_reg
;
5018 if (GET_MODE (p
->equiv_reg_src
) != GET_MODE (dest
))
5019 dest
= gen_rtx_REG (GET_MODE (p
->equiv_reg_src
),
5020 REGNO (p
->sp_equiv_reg
));
5022 emit_move_insn (dest
, p
->equiv_reg_src
);
5023 p
->equiv_reg_src
= 0;
5028 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
5029 this into place with notes indicating where the prologue ends and where
5030 the epilogue begins. Update the basic block information when possible. */
5033 thread_prologue_and_epilogue_insns (rtx f ATTRIBUTE_UNUSED
)
5037 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
5040 #ifdef HAVE_prologue
5041 rtx prologue_end
= NULL_RTX
;
5043 #if defined (HAVE_epilogue) || defined(HAVE_return)
5044 rtx epilogue_end
= NULL_RTX
;
5048 #ifdef HAVE_prologue
5052 seq
= gen_prologue ();
5055 /* Retain a map of the prologue insns. */
5056 record_insns (seq
, &prologue
);
5057 prologue_end
= emit_note (NOTE_INSN_PROLOGUE_END
);
5061 set_insn_locators (seq
, prologue_locator
);
5063 /* Can't deal with multiple successors of the entry block
5064 at the moment. Function should always have at least one
5066 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR
));
5068 insert_insn_on_edge (seq
, single_succ_edge (ENTRY_BLOCK_PTR
));
5073 /* If the exit block has no non-fake predecessors, we don't need
5075 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5076 if ((e
->flags
& EDGE_FAKE
) == 0)
5082 if (optimize
&& HAVE_return
)
5084 /* If we're allowed to generate a simple return instruction,
5085 then by definition we don't need a full epilogue. Examine
5086 the block that falls through to EXIT. If it does not
5087 contain any code, examine its predecessors and try to
5088 emit (conditional) return instructions. */
5093 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5094 if (e
->flags
& EDGE_FALLTHRU
)
5100 /* Verify that there are no active instructions in the last block. */
5101 label
= BB_END (last
);
5102 while (label
&& !LABEL_P (label
))
5104 if (active_insn_p (label
))
5106 label
= PREV_INSN (label
);
5109 if (BB_HEAD (last
) == label
&& LABEL_P (label
))
5113 for (ei2
= ei_start (last
->preds
); (e
= ei_safe_edge (ei2
)); )
5115 basic_block bb
= e
->src
;
5118 if (bb
== ENTRY_BLOCK_PTR
)
5125 if (!JUMP_P (jump
) || JUMP_LABEL (jump
) != label
)
5131 /* If we have an unconditional jump, we can replace that
5132 with a simple return instruction. */
5133 if (simplejump_p (jump
))
5135 emit_return_into_block (bb
);
5139 /* If we have a conditional jump, we can try to replace
5140 that with a conditional return instruction. */
5141 else if (condjump_p (jump
))
5143 if (! redirect_jump (jump
, 0, 0))
5149 /* If this block has only one successor, it both jumps
5150 and falls through to the fallthru block, so we can't
5152 if (single_succ_p (bb
))
5164 /* Fix up the CFG for the successful change we just made. */
5165 redirect_edge_succ (e
, EXIT_BLOCK_PTR
);
5168 /* Emit a return insn for the exit fallthru block. Whether
5169 this is still reachable will be determined later. */
5171 emit_barrier_after (BB_END (last
));
5172 emit_return_into_block (last
);
5173 epilogue_end
= BB_END (last
);
5174 single_succ_edge (last
)->flags
&= ~EDGE_FALLTHRU
;
5179 /* Find the edge that falls through to EXIT. Other edges may exist
5180 due to RETURN instructions, but those don't need epilogues.
5181 There really shouldn't be a mixture -- either all should have
5182 been converted or none, however... */
5184 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5185 if (e
->flags
& EDGE_FALLTHRU
)
5190 #ifdef HAVE_epilogue
5194 epilogue_end
= emit_note (NOTE_INSN_EPILOGUE_BEG
);
5196 seq
= gen_epilogue ();
5198 #ifdef INCOMING_RETURN_ADDR_RTX
5199 /* If this function returns with the stack depressed and we can support
5200 it, massage the epilogue to actually do that. */
5201 if (TREE_CODE (TREE_TYPE (current_function_decl
)) == FUNCTION_TYPE
5202 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl
)))
5203 seq
= keep_stack_depressed (seq
);
5206 emit_jump_insn (seq
);
5208 /* Retain a map of the epilogue insns. */
5209 record_insns (seq
, &epilogue
);
5210 set_insn_locators (seq
, epilogue_locator
);
5215 insert_insn_on_edge (seq
, e
);
5223 if (! next_active_insn (BB_END (e
->src
)))
5225 /* We have a fall-through edge to the exit block, the source is not
5226 at the end of the function, and there will be an assembler epilogue
5227 at the end of the function.
5228 We can't use force_nonfallthru here, because that would try to
5229 use return. Inserting a jump 'by hand' is extremely messy, so
5230 we take advantage of cfg_layout_finalize using
5231 fixup_fallthru_exit_predecessor. */
5232 cfg_layout_initialize (0);
5233 FOR_EACH_BB (cur_bb
)
5234 if (cur_bb
->index
>= NUM_FIXED_BLOCKS
5235 && cur_bb
->next_bb
->index
>= NUM_FIXED_BLOCKS
)
5236 cur_bb
->aux
= cur_bb
->next_bb
;
5237 cfg_layout_finalize ();
5242 commit_edge_insertions ();
5244 #ifdef HAVE_sibcall_epilogue
5245 /* Emit sibling epilogues before any sibling call sites. */
5246 for (ei
= ei_start (EXIT_BLOCK_PTR
->preds
); (e
= ei_safe_edge (ei
)); )
5248 basic_block bb
= e
->src
;
5249 rtx insn
= BB_END (bb
);
5252 || ! SIBLING_CALL_P (insn
))
5259 emit_insn (gen_sibcall_epilogue ());
5263 /* Retain a map of the epilogue insns. Used in life analysis to
5264 avoid getting rid of sibcall epilogue insns. Do this before we
5265 actually emit the sequence. */
5266 record_insns (seq
, &sibcall_epilogue
);
5267 set_insn_locators (seq
, epilogue_locator
);
5269 emit_insn_before (seq
, insn
);
5274 #ifdef HAVE_epilogue
5279 /* Similarly, move any line notes that appear after the epilogue.
5280 There is no need, however, to be quite so anal about the existence
5281 of such a note. Also possibly move
5282 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
5284 for (insn
= epilogue_end
; insn
; insn
= next
)
5286 next
= NEXT_INSN (insn
);
5288 && (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_FUNCTION_BEG
))
5289 reorder_insns (insn
, insn
, PREV_INSN (epilogue_end
));
5295 /* Reposition the prologue-end and epilogue-begin notes after instruction
5296 scheduling and delayed branch scheduling. */
5299 reposition_prologue_and_epilogue_notes (rtx f ATTRIBUTE_UNUSED
)
5301 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
5302 rtx insn
, last
, note
;
5305 if ((len
= VEC_length (int, prologue
)) > 0)
5309 /* Scan from the beginning until we reach the last prologue insn.
5310 We apparently can't depend on basic_block_{head,end} after
5312 for (insn
= f
; insn
; insn
= NEXT_INSN (insn
))
5316 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_PROLOGUE_END
)
5319 else if (contains (insn
, &prologue
))
5329 /* Find the prologue-end note if we haven't already, and
5330 move it to just after the last prologue insn. */
5333 for (note
= last
; (note
= NEXT_INSN (note
));)
5335 && NOTE_LINE_NUMBER (note
) == NOTE_INSN_PROLOGUE_END
)
5339 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
5341 last
= NEXT_INSN (last
);
5342 reorder_insns (note
, note
, last
);
5346 if ((len
= VEC_length (int, epilogue
)) > 0)
5350 /* Scan from the end until we reach the first epilogue insn.
5351 We apparently can't depend on basic_block_{head,end} after
5353 for (insn
= get_last_insn (); insn
; insn
= PREV_INSN (insn
))
5357 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_EPILOGUE_BEG
)
5360 else if (contains (insn
, &epilogue
))
5370 /* Find the epilogue-begin note if we haven't already, and
5371 move it to just before the first epilogue insn. */
5374 for (note
= insn
; (note
= PREV_INSN (note
));)
5376 && NOTE_LINE_NUMBER (note
) == NOTE_INSN_EPILOGUE_BEG
)
5380 if (PREV_INSN (last
) != note
)
5381 reorder_insns (note
, note
, PREV_INSN (last
));
5384 #endif /* HAVE_prologue or HAVE_epilogue */
5387 /* Resets insn_block_boundaries array. */
5390 reset_block_changes (void)
5392 cfun
->ib_boundaries_block
= VEC_alloc (tree
, gc
, 100);
5393 VEC_quick_push (tree
, cfun
->ib_boundaries_block
, NULL_TREE
);
5396 /* Record the boundary for BLOCK. */
5398 record_block_change (tree block
)
5406 if(!cfun
->ib_boundaries_block
)
5409 last_block
= VEC_pop (tree
, cfun
->ib_boundaries_block
);
5411 for (i
= VEC_length (tree
, cfun
->ib_boundaries_block
); i
< n
; i
++)
5412 VEC_safe_push (tree
, gc
, cfun
->ib_boundaries_block
, last_block
);
5414 VEC_safe_push (tree
, gc
, cfun
->ib_boundaries_block
, block
);
5417 /* Finishes record of boundaries. */
5419 finalize_block_changes (void)
5421 record_block_change (DECL_INITIAL (current_function_decl
));
5424 /* For INSN return the BLOCK it belongs to. */
5426 check_block_change (rtx insn
, tree
*block
)
5428 unsigned uid
= INSN_UID (insn
);
5430 if (uid
>= VEC_length (tree
, cfun
->ib_boundaries_block
))
5433 *block
= VEC_index (tree
, cfun
->ib_boundaries_block
, uid
);
5436 /* Releases the ib_boundaries_block records. */
5438 free_block_changes (void)
5440 VEC_free (tree
, gc
, cfun
->ib_boundaries_block
);
5443 /* Returns the name of the current function. */
5445 current_function_name (void)
5447 return lang_hooks
.decl_printable_name (cfun
->decl
, 2);
5452 rest_of_handle_check_leaf_regs (void)
5454 #ifdef LEAF_REGISTERS
5455 current_function_uses_only_leaf_regs
5456 = optimize
> 0 && only_leaf_regs_used () && leaf_function_p ();
5461 /* Insert a TYPE into the used types hash table of CFUN. */
5463 used_types_insert_helper (tree type
, struct function
*func
)
5465 if (type
!= NULL
&& func
!= NULL
)
5469 if (func
->used_types_hash
== NULL
)
5470 func
->used_types_hash
= htab_create_ggc (37, htab_hash_pointer
,
5471 htab_eq_pointer
, NULL
);
5472 slot
= htab_find_slot (func
->used_types_hash
, type
, INSERT
);
5478 /* Given a type, insert it into the used hash table in cfun. */
5480 used_types_insert (tree t
)
5482 while (POINTER_TYPE_P (t
) || TREE_CODE (t
) == ARRAY_TYPE
)
5484 t
= TYPE_MAIN_VARIANT (t
);
5485 if (debug_info_level
> DINFO_LEVEL_NONE
)
5486 used_types_insert_helper (t
, cfun
);
5489 struct tree_opt_pass pass_leaf_regs
=
5493 rest_of_handle_check_leaf_regs
, /* execute */
5496 0, /* static_pass_number */
5498 0, /* properties_required */
5499 0, /* properties_provided */
5500 0, /* properties_destroyed */
5501 0, /* todo_flags_start */
5502 0, /* todo_flags_finish */
5507 #include "gt-function.h"