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 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
22 /* This file handles the generation of rtl code from tree structure
23 at the level of the function as a whole.
24 It creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 `expand_function_start' is called at the beginning of a function,
28 before the function body is parsed, and `expand_function_end' is
29 called after parsing the body.
31 Call `assign_stack_local' to allocate a stack slot for a local variable.
32 This is usually done during the RTL generation for the function body,
33 but it can also be done in the reload pass when a pseudo-register does
34 not get a hard register. */
38 #include "coretypes.h"
49 #include "hard-reg-set.h"
50 #include "insn-config.h"
53 #include "basic-block.h"
58 #include "integrate.h"
59 #include "langhooks.h"
61 #include "cfglayout.h"
62 #include "tree-gimple.h"
63 #include "tree-pass.h"
69 #ifndef LOCAL_ALIGNMENT
70 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
73 #ifndef STACK_ALIGNMENT_NEEDED
74 #define STACK_ALIGNMENT_NEEDED 1
77 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
79 /* Some systems use __main in a way incompatible with its use in gcc, in these
80 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
81 give the same symbol without quotes for an alternative entry point. You
82 must define both, or neither. */
84 #define NAME__MAIN "__main"
87 /* Round a value to the lowest integer less than it that is a multiple of
88 the required alignment. Avoid using division in case the value is
89 negative. Assume the alignment is a power of two. */
90 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
92 /* Similar, but round to the next highest integer that meets the
94 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
96 /* Nonzero if function being compiled doesn't contain any calls
97 (ignoring the prologue and epilogue). This is set prior to
98 local register allocation and is valid for the remaining
100 int current_function_is_leaf
;
102 /* Nonzero if function being compiled doesn't modify the stack pointer
103 (ignoring the prologue and epilogue). This is only valid after
104 pass_stack_ptr_mod has run. */
105 int current_function_sp_is_unchanging
;
107 /* Nonzero if the function being compiled is a leaf function which only
108 uses leaf registers. This is valid after reload (specifically after
109 sched2) and is useful only if the port defines LEAF_REGISTERS. */
110 int current_function_uses_only_leaf_regs
;
112 /* Nonzero once virtual register instantiation has been done.
113 assign_stack_local uses frame_pointer_rtx when this is nonzero.
114 calls.c:emit_library_call_value_1 uses it to set up
115 post-instantiation libcalls. */
116 int virtuals_instantiated
;
118 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
119 static GTY(()) int funcdef_no
;
121 /* These variables hold pointers to functions to create and destroy
122 target specific, per-function data structures. */
123 struct machine_function
* (*init_machine_status
) (void);
125 /* The currently compiled function. */
126 struct function
*cfun
= 0;
128 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
129 static VEC(int,heap
) *prologue
;
130 static VEC(int,heap
) *epilogue
;
132 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
134 static VEC(int,heap
) *sibcall_epilogue
;
136 /* In order to evaluate some expressions, such as function calls returning
137 structures in memory, we need to temporarily allocate stack locations.
138 We record each allocated temporary in the following structure.
140 Associated with each temporary slot is a nesting level. When we pop up
141 one level, all temporaries associated with the previous level are freed.
142 Normally, all temporaries are freed after the execution of the statement
143 in which they were created. However, if we are inside a ({...}) grouping,
144 the result may be in a temporary and hence must be preserved. If the
145 result could be in a temporary, we preserve it if we can determine which
146 one it is in. If we cannot determine which temporary may contain the
147 result, all temporaries are preserved. A temporary is preserved by
148 pretending it was allocated at the previous nesting level.
150 Automatic variables are also assigned temporary slots, at the nesting
151 level where they are defined. They are marked a "kept" so that
152 free_temp_slots will not free them. */
154 struct temp_slot
GTY(())
156 /* Points to next temporary slot. */
157 struct temp_slot
*next
;
158 /* Points to previous temporary slot. */
159 struct temp_slot
*prev
;
161 /* The rtx to used to reference the slot. */
163 /* The rtx used to represent the address if not the address of the
164 slot above. May be an EXPR_LIST if multiple addresses exist. */
166 /* The alignment (in bits) of the slot. */
168 /* The size, in units, of the slot. */
170 /* The type of the object in the slot, or zero if it doesn't correspond
171 to a type. We use this to determine whether a slot can be reused.
172 It can be reused if objects of the type of the new slot will always
173 conflict with objects of the type of the old slot. */
175 /* Nonzero if this temporary is currently in use. */
177 /* Nonzero if this temporary has its address taken. */
179 /* Nesting level at which this slot is being used. */
181 /* Nonzero if this should survive a call to free_temp_slots. */
183 /* The offset of the slot from the frame_pointer, including extra space
184 for alignment. This info is for combine_temp_slots. */
185 HOST_WIDE_INT base_offset
;
186 /* The size of the slot, including extra space for alignment. This
187 info is for combine_temp_slots. */
188 HOST_WIDE_INT full_size
;
191 /* Forward declarations. */
193 static rtx
assign_stack_local_1 (enum machine_mode
, HOST_WIDE_INT
, int,
195 static struct temp_slot
*find_temp_slot_from_address (rtx
);
196 static void pad_to_arg_alignment (struct args_size
*, int, struct args_size
*);
197 static void pad_below (struct args_size
*, enum machine_mode
, tree
);
198 static void reorder_blocks_1 (rtx
, tree
, VEC(tree
,heap
) **);
199 static int all_blocks (tree
, tree
*);
200 static tree
*get_block_vector (tree
, int *);
201 extern tree
debug_find_var_in_block_tree (tree
, tree
);
202 /* We always define `record_insns' even if it's not used so that we
203 can always export `prologue_epilogue_contains'. */
204 static void record_insns (rtx
, VEC(int,heap
) **) ATTRIBUTE_UNUSED
;
205 static int contains (const_rtx
, VEC(int,heap
) **);
207 static void emit_return_into_block (basic_block
);
209 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
210 static rtx
keep_stack_depressed (rtx
);
212 static void prepare_function_start (void);
213 static void do_clobber_return_reg (rtx
, void *);
214 static void do_use_return_reg (rtx
, void *);
215 static void set_insn_locators (rtx
, int) ATTRIBUTE_UNUSED
;
217 /* Pointer to chain of `struct function' for containing functions. */
218 struct function
*outer_function_chain
;
220 /* Given a function decl for a containing function,
221 return the `struct function' for it. */
224 find_function_data (tree decl
)
228 for (p
= outer_function_chain
; p
; p
= p
->outer
)
235 /* Save the current context for compilation of a nested function.
236 This is called from language-specific code. The caller should use
237 the enter_nested langhook to save any language-specific state,
238 since this function knows only about language-independent
242 push_function_context_to (tree context ATTRIBUTE_UNUSED
)
247 allocate_struct_function (NULL
);
250 p
->outer
= outer_function_chain
;
251 outer_function_chain
= p
;
253 lang_hooks
.function
.enter_nested (p
);
259 push_function_context (void)
261 push_function_context_to (current_function_decl
);
264 /* Restore the last saved context, at the end of a nested function.
265 This function is called from language-specific code. */
268 pop_function_context_from (tree context ATTRIBUTE_UNUSED
)
270 struct function
*p
= outer_function_chain
;
273 outer_function_chain
= p
->outer
;
275 current_function_decl
= p
->decl
;
277 lang_hooks
.function
.leave_nested (p
);
279 /* Reset variables that have known state during rtx generation. */
280 virtuals_instantiated
= 0;
281 generating_concat_p
= 1;
285 pop_function_context (void)
287 pop_function_context_from (current_function_decl
);
290 /* Clear out all parts of the state in F that can safely be discarded
291 after the function has been parsed, but not compiled, to let
292 garbage collection reclaim the memory. */
295 free_after_parsing (struct function
*f
)
297 /* f->expr->forced_labels is used by code generation. */
298 /* f->emit->regno_reg_rtx is used by code generation. */
299 /* f->varasm is used by code generation. */
300 /* f->eh->eh_return_stub_label is used by code generation. */
302 lang_hooks
.function
.final (f
);
305 /* Clear out all parts of the state in F that can safely be discarded
306 after the function has been compiled, to let garbage collection
307 reclaim the memory. */
310 free_after_compilation (struct function
*f
)
312 VEC_free (int, heap
, prologue
);
313 VEC_free (int, heap
, epilogue
);
314 VEC_free (int, heap
, sibcall_epilogue
);
323 f
->x_avail_temp_slots
= NULL
;
324 f
->x_used_temp_slots
= NULL
;
325 f
->arg_offset_rtx
= NULL
;
326 f
->return_rtx
= NULL
;
327 f
->internal_arg_pointer
= NULL
;
328 f
->x_nonlocal_goto_handler_labels
= NULL
;
329 f
->x_return_label
= NULL
;
330 f
->x_naked_return_label
= NULL
;
331 f
->x_stack_slot_list
= NULL
;
332 f
->x_stack_check_probe_note
= NULL
;
333 f
->x_arg_pointer_save_area
= NULL
;
334 f
->x_parm_birth_insn
= NULL
;
335 f
->epilogue_delay_list
= NULL
;
338 /* Allocate fixed slots in the stack frame of the current function. */
340 /* Return size needed for stack frame based on slots so far allocated in
342 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
343 the caller may have to do that. */
346 get_func_frame_size (struct function
*f
)
348 if (FRAME_GROWS_DOWNWARD
)
349 return -f
->x_frame_offset
;
351 return f
->x_frame_offset
;
354 /* Return size needed for stack frame based on slots so far allocated.
355 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
356 the caller may have to do that. */
359 get_frame_size (void)
361 return get_func_frame_size (cfun
);
364 /* Issue an error message and return TRUE if frame OFFSET overflows in
365 the signed target pointer arithmetics for function FUNC. Otherwise
369 frame_offset_overflow (HOST_WIDE_INT offset
, tree func
)
371 unsigned HOST_WIDE_INT size
= FRAME_GROWS_DOWNWARD
? -offset
: offset
;
373 if (size
> ((unsigned HOST_WIDE_INT
) 1 << (GET_MODE_BITSIZE (Pmode
) - 1))
374 /* Leave room for the fixed part of the frame. */
375 - 64 * UNITS_PER_WORD
)
377 error ("%Jtotal size of local objects too large", func
);
384 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
385 with machine mode MODE.
387 ALIGN controls the amount of alignment for the address of the slot:
388 0 means according to MODE,
389 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
390 -2 means use BITS_PER_UNIT,
391 positive specifies alignment boundary in bits.
393 We do not round to stack_boundary here.
395 FUNCTION specifies the function to allocate in. */
398 assign_stack_local_1 (enum machine_mode mode
, HOST_WIDE_INT size
, int align
,
399 struct function
*function
)
402 int bigend_correction
= 0;
403 unsigned int alignment
;
404 int frame_off
, frame_alignment
, frame_phase
;
411 alignment
= BIGGEST_ALIGNMENT
;
413 alignment
= GET_MODE_ALIGNMENT (mode
);
415 /* Allow the target to (possibly) increase the alignment of this
417 type
= lang_hooks
.types
.type_for_mode (mode
, 0);
419 alignment
= LOCAL_ALIGNMENT (type
, alignment
);
421 alignment
/= BITS_PER_UNIT
;
423 else if (align
== -1)
425 alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
426 size
= CEIL_ROUND (size
, alignment
);
428 else if (align
== -2)
429 alignment
= 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
431 alignment
= align
/ BITS_PER_UNIT
;
433 if (FRAME_GROWS_DOWNWARD
)
434 function
->x_frame_offset
-= size
;
436 /* Ignore alignment we can't do with expected alignment of the boundary. */
437 if (alignment
* BITS_PER_UNIT
> PREFERRED_STACK_BOUNDARY
)
438 alignment
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
440 if (function
->stack_alignment_needed
< alignment
* BITS_PER_UNIT
)
441 function
->stack_alignment_needed
= alignment
* BITS_PER_UNIT
;
443 /* Calculate how many bytes the start of local variables is off from
445 frame_alignment
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
446 frame_off
= STARTING_FRAME_OFFSET
% frame_alignment
;
447 frame_phase
= frame_off
? frame_alignment
- frame_off
: 0;
449 /* Round the frame offset to the specified alignment. The default is
450 to always honor requests to align the stack but a port may choose to
451 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
452 if (STACK_ALIGNMENT_NEEDED
456 /* We must be careful here, since FRAME_OFFSET might be negative and
457 division with a negative dividend isn't as well defined as we might
458 like. So we instead assume that ALIGNMENT is a power of two and
459 use logical operations which are unambiguous. */
460 if (FRAME_GROWS_DOWNWARD
)
461 function
->x_frame_offset
462 = (FLOOR_ROUND (function
->x_frame_offset
- frame_phase
,
463 (unsigned HOST_WIDE_INT
) alignment
)
466 function
->x_frame_offset
467 = (CEIL_ROUND (function
->x_frame_offset
- frame_phase
,
468 (unsigned HOST_WIDE_INT
) alignment
)
472 /* On a big-endian machine, if we are allocating more space than we will use,
473 use the least significant bytes of those that are allocated. */
474 if (BYTES_BIG_ENDIAN
&& mode
!= BLKmode
&& GET_MODE_SIZE (mode
) < size
)
475 bigend_correction
= size
- GET_MODE_SIZE (mode
);
477 /* If we have already instantiated virtual registers, return the actual
478 address relative to the frame pointer. */
479 if (function
== cfun
&& virtuals_instantiated
)
480 addr
= plus_constant (frame_pointer_rtx
,
482 (frame_offset
+ bigend_correction
483 + STARTING_FRAME_OFFSET
, Pmode
));
485 addr
= plus_constant (virtual_stack_vars_rtx
,
487 (function
->x_frame_offset
+ bigend_correction
,
490 if (!FRAME_GROWS_DOWNWARD
)
491 function
->x_frame_offset
+= size
;
493 x
= gen_rtx_MEM (mode
, addr
);
494 MEM_NOTRAP_P (x
) = 1;
496 function
->x_stack_slot_list
497 = gen_rtx_EXPR_LIST (VOIDmode
, x
, function
->x_stack_slot_list
);
499 if (frame_offset_overflow (function
->x_frame_offset
, function
->decl
))
500 function
->x_frame_offset
= 0;
505 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
509 assign_stack_local (enum machine_mode mode
, HOST_WIDE_INT size
, int align
)
511 return assign_stack_local_1 (mode
, size
, align
, cfun
);
515 /* Removes temporary slot TEMP from LIST. */
518 cut_slot_from_list (struct temp_slot
*temp
, struct temp_slot
**list
)
521 temp
->next
->prev
= temp
->prev
;
523 temp
->prev
->next
= temp
->next
;
527 temp
->prev
= temp
->next
= NULL
;
530 /* Inserts temporary slot TEMP to LIST. */
533 insert_slot_to_list (struct temp_slot
*temp
, struct temp_slot
**list
)
537 (*list
)->prev
= temp
;
542 /* Returns the list of used temp slots at LEVEL. */
544 static struct temp_slot
**
545 temp_slots_at_level (int level
)
547 if (level
>= (int) VEC_length (temp_slot_p
, used_temp_slots
))
548 VEC_safe_grow_cleared (temp_slot_p
, gc
, used_temp_slots
, level
+ 1);
550 return &(VEC_address (temp_slot_p
, used_temp_slots
)[level
]);
553 /* Returns the maximal temporary slot level. */
556 max_slot_level (void)
558 if (!used_temp_slots
)
561 return VEC_length (temp_slot_p
, used_temp_slots
) - 1;
564 /* Moves temporary slot TEMP to LEVEL. */
567 move_slot_to_level (struct temp_slot
*temp
, int level
)
569 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
570 insert_slot_to_list (temp
, temp_slots_at_level (level
));
574 /* Make temporary slot TEMP available. */
577 make_slot_available (struct temp_slot
*temp
)
579 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
580 insert_slot_to_list (temp
, &avail_temp_slots
);
585 /* Allocate a temporary stack slot and record it for possible later
588 MODE is the machine mode to be given to the returned rtx.
590 SIZE is the size in units of the space required. We do no rounding here
591 since assign_stack_local will do any required rounding.
593 KEEP is 1 if this slot is to be retained after a call to
594 free_temp_slots. Automatic variables for a block are allocated
595 with this flag. KEEP values of 2 or 3 were needed respectively
596 for variables whose lifetime is controlled by CLEANUP_POINT_EXPRs
597 or for SAVE_EXPRs, but they are now unused.
599 TYPE is the type that will be used for the stack slot. */
602 assign_stack_temp_for_type (enum machine_mode mode
, HOST_WIDE_INT size
,
606 struct temp_slot
*p
, *best_p
= 0, *selected
= NULL
, **pp
;
609 /* If SIZE is -1 it means that somebody tried to allocate a temporary
610 of a variable size. */
611 gcc_assert (size
!= -1);
613 /* These are now unused. */
614 gcc_assert (keep
<= 1);
617 align
= BIGGEST_ALIGNMENT
;
619 align
= GET_MODE_ALIGNMENT (mode
);
622 type
= lang_hooks
.types
.type_for_mode (mode
, 0);
625 align
= LOCAL_ALIGNMENT (type
, align
);
627 /* Try to find an available, already-allocated temporary of the proper
628 mode which meets the size and alignment requirements. Choose the
629 smallest one with the closest alignment.
631 If assign_stack_temp is called outside of the tree->rtl expansion,
632 we cannot reuse the stack slots (that may still refer to
633 VIRTUAL_STACK_VARS_REGNUM). */
634 if (!virtuals_instantiated
)
636 for (p
= avail_temp_slots
; p
; p
= p
->next
)
638 if (p
->align
>= align
&& p
->size
>= size
639 && GET_MODE (p
->slot
) == mode
640 && objects_must_conflict_p (p
->type
, type
)
641 && (best_p
== 0 || best_p
->size
> p
->size
642 || (best_p
->size
== p
->size
&& best_p
->align
> p
->align
)))
644 if (p
->align
== align
&& p
->size
== size
)
647 cut_slot_from_list (selected
, &avail_temp_slots
);
656 /* Make our best, if any, the one to use. */
660 cut_slot_from_list (selected
, &avail_temp_slots
);
662 /* If there are enough aligned bytes left over, make them into a new
663 temp_slot so that the extra bytes don't get wasted. Do this only
664 for BLKmode slots, so that we can be sure of the alignment. */
665 if (GET_MODE (best_p
->slot
) == BLKmode
)
667 int alignment
= best_p
->align
/ BITS_PER_UNIT
;
668 HOST_WIDE_INT rounded_size
= CEIL_ROUND (size
, alignment
);
670 if (best_p
->size
- rounded_size
>= alignment
)
672 p
= ggc_alloc (sizeof (struct temp_slot
));
673 p
->in_use
= p
->addr_taken
= 0;
674 p
->size
= best_p
->size
- rounded_size
;
675 p
->base_offset
= best_p
->base_offset
+ rounded_size
;
676 p
->full_size
= best_p
->full_size
- rounded_size
;
677 p
->slot
= adjust_address_nv (best_p
->slot
, BLKmode
, rounded_size
);
678 p
->align
= best_p
->align
;
680 p
->type
= best_p
->type
;
681 insert_slot_to_list (p
, &avail_temp_slots
);
683 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, p
->slot
,
686 best_p
->size
= rounded_size
;
687 best_p
->full_size
= rounded_size
;
692 /* If we still didn't find one, make a new temporary. */
695 HOST_WIDE_INT frame_offset_old
= frame_offset
;
697 p
= ggc_alloc (sizeof (struct temp_slot
));
699 /* We are passing an explicit alignment request to assign_stack_local.
700 One side effect of that is assign_stack_local will not round SIZE
701 to ensure the frame offset remains suitably aligned.
703 So for requests which depended on the rounding of SIZE, we go ahead
704 and round it now. We also make sure ALIGNMENT is at least
705 BIGGEST_ALIGNMENT. */
706 gcc_assert (mode
!= BLKmode
|| align
== BIGGEST_ALIGNMENT
);
707 p
->slot
= assign_stack_local (mode
,
709 ? CEIL_ROUND (size
, (int) align
/ BITS_PER_UNIT
)
715 /* The following slot size computation is necessary because we don't
716 know the actual size of the temporary slot until assign_stack_local
717 has performed all the frame alignment and size rounding for the
718 requested temporary. Note that extra space added for alignment
719 can be either above or below this stack slot depending on which
720 way the frame grows. We include the extra space if and only if it
721 is above this slot. */
722 if (FRAME_GROWS_DOWNWARD
)
723 p
->size
= frame_offset_old
- frame_offset
;
727 /* Now define the fields used by combine_temp_slots. */
728 if (FRAME_GROWS_DOWNWARD
)
730 p
->base_offset
= frame_offset
;
731 p
->full_size
= frame_offset_old
- frame_offset
;
735 p
->base_offset
= frame_offset_old
;
736 p
->full_size
= frame_offset
- frame_offset_old
;
747 p
->level
= temp_slot_level
;
750 pp
= temp_slots_at_level (p
->level
);
751 insert_slot_to_list (p
, pp
);
753 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
754 slot
= gen_rtx_MEM (mode
, XEXP (p
->slot
, 0));
755 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, slot
, stack_slot_list
);
757 /* If we know the alias set for the memory that will be used, use
758 it. If there's no TYPE, then we don't know anything about the
759 alias set for the memory. */
760 set_mem_alias_set (slot
, type
? get_alias_set (type
) : 0);
761 set_mem_align (slot
, align
);
763 /* If a type is specified, set the relevant flags. */
766 MEM_VOLATILE_P (slot
) = TYPE_VOLATILE (type
);
767 MEM_SET_IN_STRUCT_P (slot
, (AGGREGATE_TYPE_P (type
)
768 || TREE_CODE (type
) == COMPLEX_TYPE
));
770 MEM_NOTRAP_P (slot
) = 1;
775 /* Allocate a temporary stack slot and record it for possible later
776 reuse. First three arguments are same as in preceding function. */
779 assign_stack_temp (enum machine_mode mode
, HOST_WIDE_INT size
, int keep
)
781 return assign_stack_temp_for_type (mode
, size
, keep
, NULL_TREE
);
784 /* Assign a temporary.
785 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
786 and so that should be used in error messages. In either case, we
787 allocate of the given type.
788 KEEP is as for assign_stack_temp.
789 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
790 it is 0 if a register is OK.
791 DONT_PROMOTE is 1 if we should not promote values in register
795 assign_temp (tree type_or_decl
, int keep
, int memory_required
,
796 int dont_promote ATTRIBUTE_UNUSED
)
799 enum machine_mode mode
;
804 if (DECL_P (type_or_decl
))
805 decl
= type_or_decl
, type
= TREE_TYPE (decl
);
807 decl
= NULL
, type
= type_or_decl
;
809 mode
= TYPE_MODE (type
);
811 unsignedp
= TYPE_UNSIGNED (type
);
814 if (mode
== BLKmode
|| memory_required
)
816 HOST_WIDE_INT size
= int_size_in_bytes (type
);
819 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
820 problems with allocating the stack space. */
824 /* Unfortunately, we don't yet know how to allocate variable-sized
825 temporaries. However, sometimes we can find a fixed upper limit on
826 the size, so try that instead. */
828 size
= max_int_size_in_bytes (type
);
830 /* The size of the temporary may be too large to fit into an integer. */
831 /* ??? Not sure this should happen except for user silliness, so limit
832 this to things that aren't compiler-generated temporaries. The
833 rest of the time we'll die in assign_stack_temp_for_type. */
834 if (decl
&& size
== -1
835 && TREE_CODE (TYPE_SIZE_UNIT (type
)) == INTEGER_CST
)
837 error ("size of variable %q+D is too large", decl
);
841 tmp
= assign_stack_temp_for_type (mode
, size
, keep
, type
);
847 mode
= promote_mode (type
, mode
, &unsignedp
, 0);
850 return gen_reg_rtx (mode
);
853 /* Combine temporary stack slots which are adjacent on the stack.
855 This allows for better use of already allocated stack space. This is only
856 done for BLKmode slots because we can be sure that we won't have alignment
857 problems in this case. */
860 combine_temp_slots (void)
862 struct temp_slot
*p
, *q
, *next
, *next_q
;
865 /* We can't combine slots, because the information about which slot
866 is in which alias set will be lost. */
867 if (flag_strict_aliasing
)
870 /* If there are a lot of temp slots, don't do anything unless
871 high levels of optimization. */
872 if (! flag_expensive_optimizations
)
873 for (p
= avail_temp_slots
, num_slots
= 0; p
; p
= p
->next
, num_slots
++)
874 if (num_slots
> 100 || (num_slots
> 10 && optimize
== 0))
877 for (p
= avail_temp_slots
; p
; p
= next
)
883 if (GET_MODE (p
->slot
) != BLKmode
)
886 for (q
= p
->next
; q
; q
= next_q
)
892 if (GET_MODE (q
->slot
) != BLKmode
)
895 if (p
->base_offset
+ p
->full_size
== q
->base_offset
)
897 /* Q comes after P; combine Q into P. */
899 p
->full_size
+= q
->full_size
;
902 else if (q
->base_offset
+ q
->full_size
== p
->base_offset
)
904 /* P comes after Q; combine P into Q. */
906 q
->full_size
+= p
->full_size
;
911 cut_slot_from_list (q
, &avail_temp_slots
);
914 /* Either delete P or advance past it. */
916 cut_slot_from_list (p
, &avail_temp_slots
);
920 /* Find the temp slot corresponding to the object at address X. */
922 static struct temp_slot
*
923 find_temp_slot_from_address (rtx x
)
929 for (i
= max_slot_level (); i
>= 0; i
--)
930 for (p
= *temp_slots_at_level (i
); p
; p
= p
->next
)
932 if (XEXP (p
->slot
, 0) == x
934 || (GET_CODE (x
) == PLUS
935 && XEXP (x
, 0) == virtual_stack_vars_rtx
936 && GET_CODE (XEXP (x
, 1)) == CONST_INT
937 && INTVAL (XEXP (x
, 1)) >= p
->base_offset
938 && INTVAL (XEXP (x
, 1)) < p
->base_offset
+ p
->full_size
))
941 else if (p
->address
!= 0 && GET_CODE (p
->address
) == EXPR_LIST
)
942 for (next
= p
->address
; next
; next
= XEXP (next
, 1))
943 if (XEXP (next
, 0) == x
)
947 /* If we have a sum involving a register, see if it points to a temp
949 if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 0))
950 && (p
= find_temp_slot_from_address (XEXP (x
, 0))) != 0)
952 else if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 1))
953 && (p
= find_temp_slot_from_address (XEXP (x
, 1))) != 0)
959 /* Indicate that NEW is an alternate way of referring to the temp slot
960 that previously was known by OLD. */
963 update_temp_slot_address (rtx old
, rtx
new)
967 if (rtx_equal_p (old
, new))
970 p
= find_temp_slot_from_address (old
);
972 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
973 is a register, see if one operand of the PLUS is a temporary
974 location. If so, NEW points into it. Otherwise, if both OLD and
975 NEW are a PLUS and if there is a register in common between them.
976 If so, try a recursive call on those values. */
979 if (GET_CODE (old
) != PLUS
)
984 update_temp_slot_address (XEXP (old
, 0), new);
985 update_temp_slot_address (XEXP (old
, 1), new);
988 else if (GET_CODE (new) != PLUS
)
991 if (rtx_equal_p (XEXP (old
, 0), XEXP (new, 0)))
992 update_temp_slot_address (XEXP (old
, 1), XEXP (new, 1));
993 else if (rtx_equal_p (XEXP (old
, 1), XEXP (new, 0)))
994 update_temp_slot_address (XEXP (old
, 0), XEXP (new, 1));
995 else if (rtx_equal_p (XEXP (old
, 0), XEXP (new, 1)))
996 update_temp_slot_address (XEXP (old
, 1), XEXP (new, 0));
997 else if (rtx_equal_p (XEXP (old
, 1), XEXP (new, 1)))
998 update_temp_slot_address (XEXP (old
, 0), XEXP (new, 0));
1003 /* Otherwise add an alias for the temp's address. */
1004 else if (p
->address
== 0)
1008 if (GET_CODE (p
->address
) != EXPR_LIST
)
1009 p
->address
= gen_rtx_EXPR_LIST (VOIDmode
, p
->address
, NULL_RTX
);
1011 p
->address
= gen_rtx_EXPR_LIST (VOIDmode
, new, p
->address
);
1015 /* If X could be a reference to a temporary slot, mark the fact that its
1016 address was taken. */
1019 mark_temp_addr_taken (rtx x
)
1021 struct temp_slot
*p
;
1026 /* If X is not in memory or is at a constant address, it cannot be in
1027 a temporary slot. */
1028 if (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0)))
1031 p
= find_temp_slot_from_address (XEXP (x
, 0));
1036 /* If X could be a reference to a temporary slot, mark that slot as
1037 belonging to the to one level higher than the current level. If X
1038 matched one of our slots, just mark that one. Otherwise, we can't
1039 easily predict which it is, so upgrade all of them. Kept slots
1040 need not be touched.
1042 This is called when an ({...}) construct occurs and a statement
1043 returns a value in memory. */
1046 preserve_temp_slots (rtx x
)
1048 struct temp_slot
*p
= 0, *next
;
1050 /* If there is no result, we still might have some objects whose address
1051 were taken, so we need to make sure they stay around. */
1054 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1059 move_slot_to_level (p
, temp_slot_level
- 1);
1065 /* If X is a register that is being used as a pointer, see if we have
1066 a temporary slot we know it points to. To be consistent with
1067 the code below, we really should preserve all non-kept slots
1068 if we can't find a match, but that seems to be much too costly. */
1069 if (REG_P (x
) && REG_POINTER (x
))
1070 p
= find_temp_slot_from_address (x
);
1072 /* If X is not in memory or is at a constant address, it cannot be in
1073 a temporary slot, but it can contain something whose address was
1075 if (p
== 0 && (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0))))
1077 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1082 move_slot_to_level (p
, temp_slot_level
- 1);
1088 /* First see if we can find a match. */
1090 p
= find_temp_slot_from_address (XEXP (x
, 0));
1094 /* Move everything at our level whose address was taken to our new
1095 level in case we used its address. */
1096 struct temp_slot
*q
;
1098 if (p
->level
== temp_slot_level
)
1100 for (q
= *temp_slots_at_level (temp_slot_level
); q
; q
= next
)
1104 if (p
!= q
&& q
->addr_taken
)
1105 move_slot_to_level (q
, temp_slot_level
- 1);
1108 move_slot_to_level (p
, temp_slot_level
- 1);
1114 /* Otherwise, preserve all non-kept slots at this level. */
1115 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1120 move_slot_to_level (p
, temp_slot_level
- 1);
1124 /* Free all temporaries used so far. This is normally called at the
1125 end of generating code for a statement. */
1128 free_temp_slots (void)
1130 struct temp_slot
*p
, *next
;
1132 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1137 make_slot_available (p
);
1140 combine_temp_slots ();
1143 /* Push deeper into the nesting level for stack temporaries. */
1146 push_temp_slots (void)
1151 /* Pop a temporary nesting level. All slots in use in the current level
1155 pop_temp_slots (void)
1157 struct temp_slot
*p
, *next
;
1159 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1162 make_slot_available (p
);
1165 combine_temp_slots ();
1170 /* Initialize temporary slots. */
1173 init_temp_slots (void)
1175 /* We have not allocated any temporaries yet. */
1176 avail_temp_slots
= 0;
1177 used_temp_slots
= 0;
1178 temp_slot_level
= 0;
1181 /* These routines are responsible for converting virtual register references
1182 to the actual hard register references once RTL generation is complete.
1184 The following four variables are used for communication between the
1185 routines. They contain the offsets of the virtual registers from their
1186 respective hard registers. */
1188 static int in_arg_offset
;
1189 static int var_offset
;
1190 static int dynamic_offset
;
1191 static int out_arg_offset
;
1192 static int cfa_offset
;
1194 /* In most machines, the stack pointer register is equivalent to the bottom
1197 #ifndef STACK_POINTER_OFFSET
1198 #define STACK_POINTER_OFFSET 0
1201 /* If not defined, pick an appropriate default for the offset of dynamically
1202 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1203 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1205 #ifndef STACK_DYNAMIC_OFFSET
1207 /* The bottom of the stack points to the actual arguments. If
1208 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1209 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1210 stack space for register parameters is not pushed by the caller, but
1211 rather part of the fixed stack areas and hence not included in
1212 `current_function_outgoing_args_size'. Nevertheless, we must allow
1213 for it when allocating stack dynamic objects. */
1215 #if defined(REG_PARM_STACK_SPACE)
1216 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1217 ((ACCUMULATE_OUTGOING_ARGS \
1218 ? (current_function_outgoing_args_size \
1219 + (OUTGOING_REG_PARM_STACK_SPACE ? 0 : REG_PARM_STACK_SPACE (FNDECL))) \
1220 : 0) + (STACK_POINTER_OFFSET))
1222 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1223 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
1224 + (STACK_POINTER_OFFSET))
1229 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1230 is a virtual register, return the equivalent hard register and set the
1231 offset indirectly through the pointer. Otherwise, return 0. */
1234 instantiate_new_reg (rtx x
, HOST_WIDE_INT
*poffset
)
1237 HOST_WIDE_INT offset
;
1239 if (x
== virtual_incoming_args_rtx
)
1240 new = arg_pointer_rtx
, offset
= in_arg_offset
;
1241 else if (x
== virtual_stack_vars_rtx
)
1242 new = frame_pointer_rtx
, offset
= var_offset
;
1243 else if (x
== virtual_stack_dynamic_rtx
)
1244 new = stack_pointer_rtx
, offset
= dynamic_offset
;
1245 else if (x
== virtual_outgoing_args_rtx
)
1246 new = stack_pointer_rtx
, offset
= out_arg_offset
;
1247 else if (x
== virtual_cfa_rtx
)
1249 #ifdef FRAME_POINTER_CFA_OFFSET
1250 new = frame_pointer_rtx
;
1252 new = arg_pointer_rtx
;
1254 offset
= cfa_offset
;
1263 /* A subroutine of instantiate_virtual_regs, called via for_each_rtx.
1264 Instantiate any virtual registers present inside of *LOC. The expression
1265 is simplified, as much as possible, but is not to be considered "valid"
1266 in any sense implied by the target. If any change is made, set CHANGED
1270 instantiate_virtual_regs_in_rtx (rtx
*loc
, void *data
)
1272 HOST_WIDE_INT offset
;
1273 bool *changed
= (bool *) data
;
1280 switch (GET_CODE (x
))
1283 new = instantiate_new_reg (x
, &offset
);
1286 *loc
= plus_constant (new, offset
);
1293 new = instantiate_new_reg (XEXP (x
, 0), &offset
);
1296 new = plus_constant (new, offset
);
1297 *loc
= simplify_gen_binary (PLUS
, GET_MODE (x
), new, XEXP (x
, 1));
1303 /* FIXME -- from old code */
1304 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1305 we can commute the PLUS and SUBREG because pointers into the
1306 frame are well-behaved. */
1316 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1317 matches the predicate for insn CODE operand OPERAND. */
1320 safe_insn_predicate (int code
, int operand
, rtx x
)
1322 const struct insn_operand_data
*op_data
;
1327 op_data
= &insn_data
[code
].operand
[operand
];
1328 if (op_data
->predicate
== NULL
)
1331 return op_data
->predicate (x
, op_data
->mode
);
1334 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1335 registers present inside of insn. The result will be a valid insn. */
1338 instantiate_virtual_regs_in_insn (rtx insn
)
1340 HOST_WIDE_INT offset
;
1342 bool any_change
= false;
1343 rtx set
, new, x
, seq
;
1345 /* There are some special cases to be handled first. */
1346 set
= single_set (insn
);
1349 /* We're allowed to assign to a virtual register. This is interpreted
1350 to mean that the underlying register gets assigned the inverse
1351 transformation. This is used, for example, in the handling of
1353 new = instantiate_new_reg (SET_DEST (set
), &offset
);
1358 for_each_rtx (&SET_SRC (set
), instantiate_virtual_regs_in_rtx
, NULL
);
1359 x
= simplify_gen_binary (PLUS
, GET_MODE (new), SET_SRC (set
),
1361 x
= force_operand (x
, new);
1363 emit_move_insn (new, x
);
1368 emit_insn_before (seq
, insn
);
1373 /* Handle a straight copy from a virtual register by generating a
1374 new add insn. The difference between this and falling through
1375 to the generic case is avoiding a new pseudo and eliminating a
1376 move insn in the initial rtl stream. */
1377 new = instantiate_new_reg (SET_SRC (set
), &offset
);
1378 if (new && offset
!= 0
1379 && REG_P (SET_DEST (set
))
1380 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1384 x
= expand_simple_binop (GET_MODE (SET_DEST (set
)), PLUS
,
1385 new, GEN_INT (offset
), SET_DEST (set
),
1386 1, OPTAB_LIB_WIDEN
);
1387 if (x
!= SET_DEST (set
))
1388 emit_move_insn (SET_DEST (set
), x
);
1393 emit_insn_before (seq
, insn
);
1398 extract_insn (insn
);
1399 insn_code
= INSN_CODE (insn
);
1401 /* Handle a plus involving a virtual register by determining if the
1402 operands remain valid if they're modified in place. */
1403 if (GET_CODE (SET_SRC (set
)) == PLUS
1404 && recog_data
.n_operands
>= 3
1405 && recog_data
.operand_loc
[1] == &XEXP (SET_SRC (set
), 0)
1406 && recog_data
.operand_loc
[2] == &XEXP (SET_SRC (set
), 1)
1407 && GET_CODE (recog_data
.operand
[2]) == CONST_INT
1408 && (new = instantiate_new_reg (recog_data
.operand
[1], &offset
)))
1410 offset
+= INTVAL (recog_data
.operand
[2]);
1412 /* If the sum is zero, then replace with a plain move. */
1414 && REG_P (SET_DEST (set
))
1415 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1418 emit_move_insn (SET_DEST (set
), new);
1422 emit_insn_before (seq
, insn
);
1427 x
= gen_int_mode (offset
, recog_data
.operand_mode
[2]);
1429 /* Using validate_change and apply_change_group here leaves
1430 recog_data in an invalid state. Since we know exactly what
1431 we want to check, do those two by hand. */
1432 if (safe_insn_predicate (insn_code
, 1, new)
1433 && safe_insn_predicate (insn_code
, 2, x
))
1435 *recog_data
.operand_loc
[1] = recog_data
.operand
[1] = new;
1436 *recog_data
.operand_loc
[2] = recog_data
.operand
[2] = x
;
1439 /* Fall through into the regular operand fixup loop in
1440 order to take care of operands other than 1 and 2. */
1446 extract_insn (insn
);
1447 insn_code
= INSN_CODE (insn
);
1450 /* In the general case, we expect virtual registers to appear only in
1451 operands, and then only as either bare registers or inside memories. */
1452 for (i
= 0; i
< recog_data
.n_operands
; ++i
)
1454 x
= recog_data
.operand
[i
];
1455 switch (GET_CODE (x
))
1459 rtx addr
= XEXP (x
, 0);
1460 bool changed
= false;
1462 for_each_rtx (&addr
, instantiate_virtual_regs_in_rtx
, &changed
);
1467 x
= replace_equiv_address (x
, addr
);
1471 emit_insn_before (seq
, insn
);
1476 new = instantiate_new_reg (x
, &offset
);
1485 /* Careful, special mode predicates may have stuff in
1486 insn_data[insn_code].operand[i].mode that isn't useful
1487 to us for computing a new value. */
1488 /* ??? Recognize address_operand and/or "p" constraints
1489 to see if (plus new offset) is a valid before we put
1490 this through expand_simple_binop. */
1491 x
= expand_simple_binop (GET_MODE (x
), PLUS
, new,
1492 GEN_INT (offset
), NULL_RTX
,
1493 1, OPTAB_LIB_WIDEN
);
1496 emit_insn_before (seq
, insn
);
1501 new = instantiate_new_reg (SUBREG_REG (x
), &offset
);
1507 new = expand_simple_binop (GET_MODE (new), PLUS
, new,
1508 GEN_INT (offset
), NULL_RTX
,
1509 1, OPTAB_LIB_WIDEN
);
1512 emit_insn_before (seq
, insn
);
1514 x
= simplify_gen_subreg (recog_data
.operand_mode
[i
], new,
1515 GET_MODE (new), SUBREG_BYTE (x
));
1522 /* At this point, X contains the new value for the operand.
1523 Validate the new value vs the insn predicate. Note that
1524 asm insns will have insn_code -1 here. */
1525 if (!safe_insn_predicate (insn_code
, i
, x
))
1528 x
= force_reg (insn_data
[insn_code
].operand
[i
].mode
, x
);
1532 emit_insn_before (seq
, insn
);
1535 *recog_data
.operand_loc
[i
] = recog_data
.operand
[i
] = x
;
1541 /* Propagate operand changes into the duplicates. */
1542 for (i
= 0; i
< recog_data
.n_dups
; ++i
)
1543 *recog_data
.dup_loc
[i
]
1544 = copy_rtx (recog_data
.operand
[(unsigned)recog_data
.dup_num
[i
]]);
1546 /* Force re-recognition of the instruction for validation. */
1547 INSN_CODE (insn
) = -1;
1550 if (asm_noperands (PATTERN (insn
)) >= 0)
1552 if (!check_asm_operands (PATTERN (insn
)))
1554 error_for_asm (insn
, "impossible constraint in %<asm%>");
1560 if (recog_memoized (insn
) < 0)
1561 fatal_insn_not_found (insn
);
1565 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1566 do any instantiation required. */
1569 instantiate_decl (rtx x
)
1576 /* If this is a CONCAT, recurse for the pieces. */
1577 if (GET_CODE (x
) == CONCAT
)
1579 instantiate_decl (XEXP (x
, 0));
1580 instantiate_decl (XEXP (x
, 1));
1584 /* If this is not a MEM, no need to do anything. Similarly if the
1585 address is a constant or a register that is not a virtual register. */
1590 if (CONSTANT_P (addr
)
1592 && (REGNO (addr
) < FIRST_VIRTUAL_REGISTER
1593 || REGNO (addr
) > LAST_VIRTUAL_REGISTER
)))
1596 for_each_rtx (&XEXP (x
, 0), instantiate_virtual_regs_in_rtx
, NULL
);
1599 /* Helper for instantiate_decls called via walk_tree: Process all decls
1600 in the given DECL_VALUE_EXPR. */
1603 instantiate_expr (tree
*tp
, int *walk_subtrees
, void *data ATTRIBUTE_UNUSED
)
1606 if (! EXPR_P (t
) && ! GIMPLE_STMT_P (t
))
1609 if (DECL_P (t
) && DECL_RTL_SET_P (t
))
1610 instantiate_decl (DECL_RTL (t
));
1615 /* Subroutine of instantiate_decls: Process all decls in the given
1616 BLOCK node and all its subblocks. */
1619 instantiate_decls_1 (tree let
)
1623 for (t
= BLOCK_VARS (let
); t
; t
= TREE_CHAIN (t
))
1625 if (DECL_RTL_SET_P (t
))
1626 instantiate_decl (DECL_RTL (t
));
1627 if (TREE_CODE (t
) == VAR_DECL
&& DECL_HAS_VALUE_EXPR_P (t
))
1629 tree v
= DECL_VALUE_EXPR (t
);
1630 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1634 /* Process all subblocks. */
1635 for (t
= BLOCK_SUBBLOCKS (let
); t
; t
= TREE_CHAIN (t
))
1636 instantiate_decls_1 (t
);
1639 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1640 all virtual registers in their DECL_RTL's. */
1643 instantiate_decls (tree fndecl
)
1647 /* Process all parameters of the function. */
1648 for (decl
= DECL_ARGUMENTS (fndecl
); decl
; decl
= TREE_CHAIN (decl
))
1650 instantiate_decl (DECL_RTL (decl
));
1651 instantiate_decl (DECL_INCOMING_RTL (decl
));
1652 if (DECL_HAS_VALUE_EXPR_P (decl
))
1654 tree v
= DECL_VALUE_EXPR (decl
);
1655 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1659 /* Now process all variables defined in the function or its subblocks. */
1660 instantiate_decls_1 (DECL_INITIAL (fndecl
));
1663 /* Pass through the INSNS of function FNDECL and convert virtual register
1664 references to hard register references. */
1667 instantiate_virtual_regs (void)
1671 /* Compute the offsets to use for this function. */
1672 in_arg_offset
= FIRST_PARM_OFFSET (current_function_decl
);
1673 var_offset
= STARTING_FRAME_OFFSET
;
1674 dynamic_offset
= STACK_DYNAMIC_OFFSET (current_function_decl
);
1675 out_arg_offset
= STACK_POINTER_OFFSET
;
1676 #ifdef FRAME_POINTER_CFA_OFFSET
1677 cfa_offset
= FRAME_POINTER_CFA_OFFSET (current_function_decl
);
1679 cfa_offset
= ARG_POINTER_CFA_OFFSET (current_function_decl
);
1682 /* Initialize recognition, indicating that volatile is OK. */
1685 /* Scan through all the insns, instantiating every virtual register still
1687 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
1690 /* These patterns in the instruction stream can never be recognized.
1691 Fortunately, they shouldn't contain virtual registers either. */
1692 if (GET_CODE (PATTERN (insn
)) == USE
1693 || GET_CODE (PATTERN (insn
)) == CLOBBER
1694 || GET_CODE (PATTERN (insn
)) == ADDR_VEC
1695 || GET_CODE (PATTERN (insn
)) == ADDR_DIFF_VEC
1696 || GET_CODE (PATTERN (insn
)) == ASM_INPUT
)
1699 instantiate_virtual_regs_in_insn (insn
);
1701 if (INSN_DELETED_P (insn
))
1704 for_each_rtx (®_NOTES (insn
), instantiate_virtual_regs_in_rtx
, NULL
);
1706 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1707 if (GET_CODE (insn
) == CALL_INSN
)
1708 for_each_rtx (&CALL_INSN_FUNCTION_USAGE (insn
),
1709 instantiate_virtual_regs_in_rtx
, NULL
);
1712 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1713 instantiate_decls (current_function_decl
);
1715 /* Indicate that, from now on, assign_stack_local should use
1716 frame_pointer_rtx. */
1717 virtuals_instantiated
= 1;
1721 struct tree_opt_pass pass_instantiate_virtual_regs
=
1725 instantiate_virtual_regs
, /* execute */
1728 0, /* static_pass_number */
1730 0, /* properties_required */
1731 0, /* properties_provided */
1732 0, /* properties_destroyed */
1733 0, /* todo_flags_start */
1734 TODO_dump_func
, /* todo_flags_finish */
1739 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
1740 This means a type for which function calls must pass an address to the
1741 function or get an address back from the function.
1742 EXP may be a type node or an expression (whose type is tested). */
1745 aggregate_value_p (const_tree exp
, const_tree fntype
)
1747 int i
, regno
, nregs
;
1750 const_tree type
= (TYPE_P (exp
)) ? exp
: TREE_TYPE (exp
);
1752 /* DECL node associated with FNTYPE when relevant, which we might need to
1753 check for by-invisible-reference returns, typically for CALL_EXPR input
1755 const_tree fndecl
= NULL_TREE
;
1758 switch (TREE_CODE (fntype
))
1761 fndecl
= get_callee_fndecl (fntype
);
1762 fntype
= fndecl
? TREE_TYPE (fndecl
) : 0;
1766 fntype
= TREE_TYPE (fndecl
);
1771 case IDENTIFIER_NODE
:
1775 /* We don't expect other rtl types here. */
1779 if (TREE_CODE (type
) == VOID_TYPE
)
1782 /* If the front end has decided that this needs to be passed by
1783 reference, do so. */
1784 if ((TREE_CODE (exp
) == PARM_DECL
|| TREE_CODE (exp
) == RESULT_DECL
)
1785 && DECL_BY_REFERENCE (exp
))
1788 /* If the EXPression is a CALL_EXPR, honor DECL_BY_REFERENCE set on the
1789 called function RESULT_DECL, meaning the function returns in memory by
1790 invisible reference. This check lets front-ends not set TREE_ADDRESSABLE
1791 on the function type, which used to be the way to request such a return
1792 mechanism but might now be causing troubles at gimplification time if
1793 temporaries with the function type need to be created. */
1794 if (TREE_CODE (exp
) == CALL_EXPR
&& fndecl
&& DECL_RESULT (fndecl
)
1795 && DECL_BY_REFERENCE (DECL_RESULT (fndecl
)))
1798 if (targetm
.calls
.return_in_memory (type
, fntype
))
1800 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
1801 and thus can't be returned in registers. */
1802 if (TREE_ADDRESSABLE (type
))
1804 if (flag_pcc_struct_return
&& AGGREGATE_TYPE_P (type
))
1806 /* Make sure we have suitable call-clobbered regs to return
1807 the value in; if not, we must return it in memory. */
1808 reg
= hard_function_value (type
, 0, fntype
, 0);
1810 /* If we have something other than a REG (e.g. a PARALLEL), then assume
1815 regno
= REGNO (reg
);
1816 nregs
= hard_regno_nregs
[regno
][TYPE_MODE (type
)];
1817 for (i
= 0; i
< nregs
; i
++)
1818 if (! call_used_regs
[regno
+ i
])
1823 /* Return true if we should assign DECL a pseudo register; false if it
1824 should live on the local stack. */
1827 use_register_for_decl (const_tree decl
)
1829 /* Honor volatile. */
1830 if (TREE_SIDE_EFFECTS (decl
))
1833 /* Honor addressability. */
1834 if (TREE_ADDRESSABLE (decl
))
1837 /* Only register-like things go in registers. */
1838 if (DECL_MODE (decl
) == BLKmode
)
1841 /* If -ffloat-store specified, don't put explicit float variables
1843 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
1844 propagates values across these stores, and it probably shouldn't. */
1845 if (flag_float_store
&& FLOAT_TYPE_P (TREE_TYPE (decl
)))
1848 /* If we're not interested in tracking debugging information for
1849 this decl, then we can certainly put it in a register. */
1850 if (DECL_IGNORED_P (decl
))
1853 return (optimize
|| DECL_REGISTER (decl
));
1856 /* Return true if TYPE should be passed by invisible reference. */
1859 pass_by_reference (CUMULATIVE_ARGS
*ca
, enum machine_mode mode
,
1860 tree type
, bool named_arg
)
1864 /* If this type contains non-trivial constructors, then it is
1865 forbidden for the middle-end to create any new copies. */
1866 if (TREE_ADDRESSABLE (type
))
1869 /* GCC post 3.4 passes *all* variable sized types by reference. */
1870 if (!TYPE_SIZE (type
) || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
1874 return targetm
.calls
.pass_by_reference (ca
, mode
, type
, named_arg
);
1877 /* Return true if TYPE, which is passed by reference, should be callee
1878 copied instead of caller copied. */
1881 reference_callee_copied (CUMULATIVE_ARGS
*ca
, enum machine_mode mode
,
1882 tree type
, bool named_arg
)
1884 if (type
&& TREE_ADDRESSABLE (type
))
1886 return targetm
.calls
.callee_copies (ca
, mode
, type
, named_arg
);
1889 /* Structures to communicate between the subroutines of assign_parms.
1890 The first holds data persistent across all parameters, the second
1891 is cleared out for each parameter. */
1893 struct assign_parm_data_all
1895 CUMULATIVE_ARGS args_so_far
;
1896 struct args_size stack_args_size
;
1897 tree function_result_decl
;
1899 rtx first_conversion_insn
;
1900 rtx last_conversion_insn
;
1901 HOST_WIDE_INT pretend_args_size
;
1902 HOST_WIDE_INT extra_pretend_bytes
;
1903 int reg_parm_stack_space
;
1906 struct assign_parm_data_one
1912 enum machine_mode nominal_mode
;
1913 enum machine_mode passed_mode
;
1914 enum machine_mode promoted_mode
;
1915 struct locate_and_pad_arg_data locate
;
1917 BOOL_BITFIELD named_arg
: 1;
1918 BOOL_BITFIELD passed_pointer
: 1;
1919 BOOL_BITFIELD on_stack
: 1;
1920 BOOL_BITFIELD loaded_in_reg
: 1;
1923 /* A subroutine of assign_parms. Initialize ALL. */
1926 assign_parms_initialize_all (struct assign_parm_data_all
*all
)
1930 memset (all
, 0, sizeof (*all
));
1932 fntype
= TREE_TYPE (current_function_decl
);
1934 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
1935 INIT_CUMULATIVE_INCOMING_ARGS (all
->args_so_far
, fntype
, NULL_RTX
);
1937 INIT_CUMULATIVE_ARGS (all
->args_so_far
, fntype
, NULL_RTX
,
1938 current_function_decl
, -1);
1941 #ifdef REG_PARM_STACK_SPACE
1942 all
->reg_parm_stack_space
= REG_PARM_STACK_SPACE (current_function_decl
);
1946 /* If ARGS contains entries with complex types, split the entry into two
1947 entries of the component type. Return a new list of substitutions are
1948 needed, else the old list. */
1951 split_complex_args (tree args
)
1955 /* Before allocating memory, check for the common case of no complex. */
1956 for (p
= args
; p
; p
= TREE_CHAIN (p
))
1958 tree type
= TREE_TYPE (p
);
1959 if (TREE_CODE (type
) == COMPLEX_TYPE
1960 && targetm
.calls
.split_complex_arg (type
))
1966 args
= copy_list (args
);
1968 for (p
= args
; p
; p
= TREE_CHAIN (p
))
1970 tree type
= TREE_TYPE (p
);
1971 if (TREE_CODE (type
) == COMPLEX_TYPE
1972 && targetm
.calls
.split_complex_arg (type
))
1975 tree subtype
= TREE_TYPE (type
);
1976 bool addressable
= TREE_ADDRESSABLE (p
);
1978 /* Rewrite the PARM_DECL's type with its component. */
1979 TREE_TYPE (p
) = subtype
;
1980 DECL_ARG_TYPE (p
) = TREE_TYPE (DECL_ARG_TYPE (p
));
1981 DECL_MODE (p
) = VOIDmode
;
1982 DECL_SIZE (p
) = NULL
;
1983 DECL_SIZE_UNIT (p
) = NULL
;
1984 /* If this arg must go in memory, put it in a pseudo here.
1985 We can't allow it to go in memory as per normal parms,
1986 because the usual place might not have the imag part
1987 adjacent to the real part. */
1988 DECL_ARTIFICIAL (p
) = addressable
;
1989 DECL_IGNORED_P (p
) = addressable
;
1990 TREE_ADDRESSABLE (p
) = 0;
1993 /* Build a second synthetic decl. */
1994 decl
= build_decl (PARM_DECL
, NULL_TREE
, subtype
);
1995 DECL_ARG_TYPE (decl
) = DECL_ARG_TYPE (p
);
1996 DECL_ARTIFICIAL (decl
) = addressable
;
1997 DECL_IGNORED_P (decl
) = addressable
;
1998 layout_decl (decl
, 0);
2000 /* Splice it in; skip the new decl. */
2001 TREE_CHAIN (decl
) = TREE_CHAIN (p
);
2002 TREE_CHAIN (p
) = decl
;
2010 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
2011 the hidden struct return argument, and (abi willing) complex args.
2012 Return the new parameter list. */
2015 assign_parms_augmented_arg_list (struct assign_parm_data_all
*all
)
2017 tree fndecl
= current_function_decl
;
2018 tree fntype
= TREE_TYPE (fndecl
);
2019 tree fnargs
= DECL_ARGUMENTS (fndecl
);
2021 /* If struct value address is treated as the first argument, make it so. */
2022 if (aggregate_value_p (DECL_RESULT (fndecl
), fndecl
)
2023 && ! current_function_returns_pcc_struct
2024 && targetm
.calls
.struct_value_rtx (TREE_TYPE (fndecl
), 1) == 0)
2026 tree type
= build_pointer_type (TREE_TYPE (fntype
));
2029 decl
= build_decl (PARM_DECL
, NULL_TREE
, type
);
2030 DECL_ARG_TYPE (decl
) = type
;
2031 DECL_ARTIFICIAL (decl
) = 1;
2032 DECL_IGNORED_P (decl
) = 1;
2034 TREE_CHAIN (decl
) = fnargs
;
2036 all
->function_result_decl
= decl
;
2039 all
->orig_fnargs
= fnargs
;
2041 /* If the target wants to split complex arguments into scalars, do so. */
2042 if (targetm
.calls
.split_complex_arg
)
2043 fnargs
= split_complex_args (fnargs
);
2048 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2049 data for the parameter. Incorporate ABI specifics such as pass-by-
2050 reference and type promotion. */
2053 assign_parm_find_data_types (struct assign_parm_data_all
*all
, tree parm
,
2054 struct assign_parm_data_one
*data
)
2056 tree nominal_type
, passed_type
;
2057 enum machine_mode nominal_mode
, passed_mode
, promoted_mode
;
2059 memset (data
, 0, sizeof (*data
));
2061 /* NAMED_ARG is a mis-nomer. We really mean 'non-varadic'. */
2062 if (!current_function_stdarg
)
2063 data
->named_arg
= 1; /* No varadic parms. */
2064 else if (TREE_CHAIN (parm
))
2065 data
->named_arg
= 1; /* Not the last non-varadic parm. */
2066 else if (targetm
.calls
.strict_argument_naming (&all
->args_so_far
))
2067 data
->named_arg
= 1; /* Only varadic ones are unnamed. */
2069 data
->named_arg
= 0; /* Treat as varadic. */
2071 nominal_type
= TREE_TYPE (parm
);
2072 passed_type
= DECL_ARG_TYPE (parm
);
2074 /* Look out for errors propagating this far. Also, if the parameter's
2075 type is void then its value doesn't matter. */
2076 if (TREE_TYPE (parm
) == error_mark_node
2077 /* This can happen after weird syntax errors
2078 or if an enum type is defined among the parms. */
2079 || TREE_CODE (parm
) != PARM_DECL
2080 || passed_type
== NULL
2081 || VOID_TYPE_P (nominal_type
))
2083 nominal_type
= passed_type
= void_type_node
;
2084 nominal_mode
= passed_mode
= promoted_mode
= VOIDmode
;
2088 /* Find mode of arg as it is passed, and mode of arg as it should be
2089 during execution of this function. */
2090 passed_mode
= TYPE_MODE (passed_type
);
2091 nominal_mode
= TYPE_MODE (nominal_type
);
2093 /* If the parm is to be passed as a transparent union, use the type of
2094 the first field for the tests below. We have already verified that
2095 the modes are the same. */
2096 if (TREE_CODE (passed_type
) == UNION_TYPE
2097 && TYPE_TRANSPARENT_UNION (passed_type
))
2098 passed_type
= TREE_TYPE (TYPE_FIELDS (passed_type
));
2100 /* See if this arg was passed by invisible reference. */
2101 if (pass_by_reference (&all
->args_so_far
, passed_mode
,
2102 passed_type
, data
->named_arg
))
2104 passed_type
= nominal_type
= build_pointer_type (passed_type
);
2105 data
->passed_pointer
= true;
2106 passed_mode
= nominal_mode
= Pmode
;
2109 /* Find mode as it is passed by the ABI. */
2110 promoted_mode
= passed_mode
;
2111 if (targetm
.calls
.promote_function_args (TREE_TYPE (current_function_decl
)))
2113 int unsignedp
= TYPE_UNSIGNED (passed_type
);
2114 promoted_mode
= promote_mode (passed_type
, promoted_mode
,
2119 data
->nominal_type
= nominal_type
;
2120 data
->passed_type
= passed_type
;
2121 data
->nominal_mode
= nominal_mode
;
2122 data
->passed_mode
= passed_mode
;
2123 data
->promoted_mode
= promoted_mode
;
2126 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2129 assign_parms_setup_varargs (struct assign_parm_data_all
*all
,
2130 struct assign_parm_data_one
*data
, bool no_rtl
)
2132 int varargs_pretend_bytes
= 0;
2134 targetm
.calls
.setup_incoming_varargs (&all
->args_so_far
,
2135 data
->promoted_mode
,
2137 &varargs_pretend_bytes
, no_rtl
);
2139 /* If the back-end has requested extra stack space, record how much is
2140 needed. Do not change pretend_args_size otherwise since it may be
2141 nonzero from an earlier partial argument. */
2142 if (varargs_pretend_bytes
> 0)
2143 all
->pretend_args_size
= varargs_pretend_bytes
;
2146 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2147 the incoming location of the current parameter. */
2150 assign_parm_find_entry_rtl (struct assign_parm_data_all
*all
,
2151 struct assign_parm_data_one
*data
)
2153 HOST_WIDE_INT pretend_bytes
= 0;
2157 if (data
->promoted_mode
== VOIDmode
)
2159 data
->entry_parm
= data
->stack_parm
= const0_rtx
;
2163 #ifdef FUNCTION_INCOMING_ARG
2164 entry_parm
= FUNCTION_INCOMING_ARG (all
->args_so_far
, data
->promoted_mode
,
2165 data
->passed_type
, data
->named_arg
);
2167 entry_parm
= FUNCTION_ARG (all
->args_so_far
, data
->promoted_mode
,
2168 data
->passed_type
, data
->named_arg
);
2171 if (entry_parm
== 0)
2172 data
->promoted_mode
= data
->passed_mode
;
2174 /* Determine parm's home in the stack, in case it arrives in the stack
2175 or we should pretend it did. Compute the stack position and rtx where
2176 the argument arrives and its size.
2178 There is one complexity here: If this was a parameter that would
2179 have been passed in registers, but wasn't only because it is
2180 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2181 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2182 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2183 as it was the previous time. */
2184 in_regs
= entry_parm
!= 0;
2185 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2188 if (!in_regs
&& !data
->named_arg
)
2190 if (targetm
.calls
.pretend_outgoing_varargs_named (&all
->args_so_far
))
2193 #ifdef FUNCTION_INCOMING_ARG
2194 tem
= FUNCTION_INCOMING_ARG (all
->args_so_far
, data
->promoted_mode
,
2195 data
->passed_type
, true);
2197 tem
= FUNCTION_ARG (all
->args_so_far
, data
->promoted_mode
,
2198 data
->passed_type
, true);
2200 in_regs
= tem
!= NULL
;
2204 /* If this parameter was passed both in registers and in the stack, use
2205 the copy on the stack. */
2206 if (targetm
.calls
.must_pass_in_stack (data
->promoted_mode
,
2214 partial
= targetm
.calls
.arg_partial_bytes (&all
->args_so_far
,
2215 data
->promoted_mode
,
2218 data
->partial
= partial
;
2220 /* The caller might already have allocated stack space for the
2221 register parameters. */
2222 if (partial
!= 0 && all
->reg_parm_stack_space
== 0)
2224 /* Part of this argument is passed in registers and part
2225 is passed on the stack. Ask the prologue code to extend
2226 the stack part so that we can recreate the full value.
2228 PRETEND_BYTES is the size of the registers we need to store.
2229 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2230 stack space that the prologue should allocate.
2232 Internally, gcc assumes that the argument pointer is aligned
2233 to STACK_BOUNDARY bits. This is used both for alignment
2234 optimizations (see init_emit) and to locate arguments that are
2235 aligned to more than PARM_BOUNDARY bits. We must preserve this
2236 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2237 a stack boundary. */
2239 /* We assume at most one partial arg, and it must be the first
2240 argument on the stack. */
2241 gcc_assert (!all
->extra_pretend_bytes
&& !all
->pretend_args_size
);
2243 pretend_bytes
= partial
;
2244 all
->pretend_args_size
= CEIL_ROUND (pretend_bytes
, STACK_BYTES
);
2246 /* We want to align relative to the actual stack pointer, so
2247 don't include this in the stack size until later. */
2248 all
->extra_pretend_bytes
= all
->pretend_args_size
;
2252 locate_and_pad_parm (data
->promoted_mode
, data
->passed_type
, in_regs
,
2253 entry_parm
? data
->partial
: 0, current_function_decl
,
2254 &all
->stack_args_size
, &data
->locate
);
2256 /* Adjust offsets to include the pretend args. */
2257 pretend_bytes
= all
->extra_pretend_bytes
- pretend_bytes
;
2258 data
->locate
.slot_offset
.constant
+= pretend_bytes
;
2259 data
->locate
.offset
.constant
+= pretend_bytes
;
2261 data
->entry_parm
= entry_parm
;
2264 /* A subroutine of assign_parms. If there is actually space on the stack
2265 for this parm, count it in stack_args_size and return true. */
2268 assign_parm_is_stack_parm (struct assign_parm_data_all
*all
,
2269 struct assign_parm_data_one
*data
)
2271 /* Trivially true if we've no incoming register. */
2272 if (data
->entry_parm
== NULL
)
2274 /* Also true if we're partially in registers and partially not,
2275 since we've arranged to drop the entire argument on the stack. */
2276 else if (data
->partial
!= 0)
2278 /* Also true if the target says that it's passed in both registers
2279 and on the stack. */
2280 else if (GET_CODE (data
->entry_parm
) == PARALLEL
2281 && XEXP (XVECEXP (data
->entry_parm
, 0, 0), 0) == NULL_RTX
)
2283 /* Also true if the target says that there's stack allocated for
2284 all register parameters. */
2285 else if (all
->reg_parm_stack_space
> 0)
2287 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2291 all
->stack_args_size
.constant
+= data
->locate
.size
.constant
;
2292 if (data
->locate
.size
.var
)
2293 ADD_PARM_SIZE (all
->stack_args_size
, data
->locate
.size
.var
);
2298 /* A subroutine of assign_parms. Given that this parameter is allocated
2299 stack space by the ABI, find it. */
2302 assign_parm_find_stack_rtl (tree parm
, struct assign_parm_data_one
*data
)
2304 rtx offset_rtx
, stack_parm
;
2305 unsigned int align
, boundary
;
2307 /* If we're passing this arg using a reg, make its stack home the
2308 aligned stack slot. */
2309 if (data
->entry_parm
)
2310 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.slot_offset
);
2312 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.offset
);
2314 stack_parm
= current_function_internal_arg_pointer
;
2315 if (offset_rtx
!= const0_rtx
)
2316 stack_parm
= gen_rtx_PLUS (Pmode
, stack_parm
, offset_rtx
);
2317 stack_parm
= gen_rtx_MEM (data
->promoted_mode
, stack_parm
);
2319 set_mem_attributes (stack_parm
, parm
, 1);
2321 boundary
= data
->locate
.boundary
;
2322 align
= BITS_PER_UNIT
;
2324 /* If we're padding upward, we know that the alignment of the slot
2325 is FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2326 intentionally forcing upward padding. Otherwise we have to come
2327 up with a guess at the alignment based on OFFSET_RTX. */
2328 if (data
->locate
.where_pad
!= downward
|| data
->entry_parm
)
2330 else if (GET_CODE (offset_rtx
) == CONST_INT
)
2332 align
= INTVAL (offset_rtx
) * BITS_PER_UNIT
| boundary
;
2333 align
= align
& -align
;
2335 set_mem_align (stack_parm
, align
);
2337 if (data
->entry_parm
)
2338 set_reg_attrs_for_parm (data
->entry_parm
, stack_parm
);
2340 data
->stack_parm
= stack_parm
;
2343 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2344 always valid and contiguous. */
2347 assign_parm_adjust_entry_rtl (struct assign_parm_data_one
*data
)
2349 rtx entry_parm
= data
->entry_parm
;
2350 rtx stack_parm
= data
->stack_parm
;
2352 /* If this parm was passed part in regs and part in memory, pretend it
2353 arrived entirely in memory by pushing the register-part onto the stack.
2354 In the special case of a DImode or DFmode that is split, we could put
2355 it together in a pseudoreg directly, but for now that's not worth
2357 if (data
->partial
!= 0)
2359 /* Handle calls that pass values in multiple non-contiguous
2360 locations. The Irix 6 ABI has examples of this. */
2361 if (GET_CODE (entry_parm
) == PARALLEL
)
2362 emit_group_store (validize_mem (stack_parm
), entry_parm
,
2364 int_size_in_bytes (data
->passed_type
));
2367 gcc_assert (data
->partial
% UNITS_PER_WORD
== 0);
2368 move_block_from_reg (REGNO (entry_parm
), validize_mem (stack_parm
),
2369 data
->partial
/ UNITS_PER_WORD
);
2372 entry_parm
= stack_parm
;
2375 /* If we didn't decide this parm came in a register, by default it came
2377 else if (entry_parm
== NULL
)
2378 entry_parm
= stack_parm
;
2380 /* When an argument is passed in multiple locations, we can't make use
2381 of this information, but we can save some copying if the whole argument
2382 is passed in a single register. */
2383 else if (GET_CODE (entry_parm
) == PARALLEL
2384 && data
->nominal_mode
!= BLKmode
2385 && data
->passed_mode
!= BLKmode
)
2387 size_t i
, len
= XVECLEN (entry_parm
, 0);
2389 for (i
= 0; i
< len
; i
++)
2390 if (XEXP (XVECEXP (entry_parm
, 0, i
), 0) != NULL_RTX
2391 && REG_P (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2392 && (GET_MODE (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2393 == data
->passed_mode
)
2394 && INTVAL (XEXP (XVECEXP (entry_parm
, 0, i
), 1)) == 0)
2396 entry_parm
= XEXP (XVECEXP (entry_parm
, 0, i
), 0);
2401 data
->entry_parm
= entry_parm
;
2404 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2405 always valid and properly aligned. */
2408 assign_parm_adjust_stack_rtl (struct assign_parm_data_one
*data
)
2410 rtx stack_parm
= data
->stack_parm
;
2412 /* If we can't trust the parm stack slot to be aligned enough for its
2413 ultimate type, don't use that slot after entry. We'll make another
2414 stack slot, if we need one. */
2416 && ((STRICT_ALIGNMENT
2417 && GET_MODE_ALIGNMENT (data
->nominal_mode
) > MEM_ALIGN (stack_parm
))
2418 || (data
->nominal_type
2419 && TYPE_ALIGN (data
->nominal_type
) > MEM_ALIGN (stack_parm
)
2420 && MEM_ALIGN (stack_parm
) < PREFERRED_STACK_BOUNDARY
)))
2423 /* If parm was passed in memory, and we need to convert it on entry,
2424 don't store it back in that same slot. */
2425 else if (data
->entry_parm
== stack_parm
2426 && data
->nominal_mode
!= BLKmode
2427 && data
->nominal_mode
!= data
->passed_mode
)
2430 /* If stack protection is in effect for this function, don't leave any
2431 pointers in their passed stack slots. */
2432 else if (cfun
->stack_protect_guard
2433 && (flag_stack_protect
== 2
2434 || data
->passed_pointer
2435 || POINTER_TYPE_P (data
->nominal_type
)))
2438 data
->stack_parm
= stack_parm
;
2441 /* A subroutine of assign_parms. Return true if the current parameter
2442 should be stored as a BLKmode in the current frame. */
2445 assign_parm_setup_block_p (struct assign_parm_data_one
*data
)
2447 if (data
->nominal_mode
== BLKmode
)
2449 if (GET_CODE (data
->entry_parm
) == PARALLEL
)
2452 #ifdef BLOCK_REG_PADDING
2453 /* Only assign_parm_setup_block knows how to deal with register arguments
2454 that are padded at the least significant end. */
2455 if (REG_P (data
->entry_parm
)
2456 && GET_MODE_SIZE (data
->promoted_mode
) < UNITS_PER_WORD
2457 && (BLOCK_REG_PADDING (data
->passed_mode
, data
->passed_type
, 1)
2458 == (BYTES_BIG_ENDIAN
? upward
: downward
)))
2465 /* A subroutine of assign_parms. Arrange for the parameter to be
2466 present and valid in DATA->STACK_RTL. */
2469 assign_parm_setup_block (struct assign_parm_data_all
*all
,
2470 tree parm
, struct assign_parm_data_one
*data
)
2472 rtx entry_parm
= data
->entry_parm
;
2473 rtx stack_parm
= data
->stack_parm
;
2475 HOST_WIDE_INT size_stored
;
2476 rtx orig_entry_parm
= entry_parm
;
2478 if (GET_CODE (entry_parm
) == PARALLEL
)
2479 entry_parm
= emit_group_move_into_temps (entry_parm
);
2481 /* If we've a non-block object that's nevertheless passed in parts,
2482 reconstitute it in register operations rather than on the stack. */
2483 if (GET_CODE (entry_parm
) == PARALLEL
2484 && data
->nominal_mode
!= BLKmode
)
2486 rtx elt0
= XEXP (XVECEXP (orig_entry_parm
, 0, 0), 0);
2488 if ((XVECLEN (entry_parm
, 0) > 1
2489 || hard_regno_nregs
[REGNO (elt0
)][GET_MODE (elt0
)] > 1)
2490 && use_register_for_decl (parm
))
2492 rtx parmreg
= gen_reg_rtx (data
->nominal_mode
);
2494 push_to_sequence2 (all
->first_conversion_insn
,
2495 all
->last_conversion_insn
);
2497 /* For values returned in multiple registers, handle possible
2498 incompatible calls to emit_group_store.
2500 For example, the following would be invalid, and would have to
2501 be fixed by the conditional below:
2503 emit_group_store ((reg:SF), (parallel:DF))
2504 emit_group_store ((reg:SI), (parallel:DI))
2506 An example of this are doubles in e500 v2:
2507 (parallel:DF (expr_list (reg:SI) (const_int 0))
2508 (expr_list (reg:SI) (const_int 4))). */
2509 if (data
->nominal_mode
!= data
->passed_mode
)
2511 rtx t
= gen_reg_rtx (GET_MODE (entry_parm
));
2512 emit_group_store (t
, entry_parm
, NULL_TREE
,
2513 GET_MODE_SIZE (GET_MODE (entry_parm
)));
2514 convert_move (parmreg
, t
, 0);
2517 emit_group_store (parmreg
, entry_parm
, data
->nominal_type
,
2518 int_size_in_bytes (data
->nominal_type
));
2520 all
->first_conversion_insn
= get_insns ();
2521 all
->last_conversion_insn
= get_last_insn ();
2524 SET_DECL_RTL (parm
, parmreg
);
2529 size
= int_size_in_bytes (data
->passed_type
);
2530 size_stored
= CEIL_ROUND (size
, UNITS_PER_WORD
);
2531 if (stack_parm
== 0)
2533 DECL_ALIGN (parm
) = MAX (DECL_ALIGN (parm
), BITS_PER_WORD
);
2534 stack_parm
= assign_stack_local (BLKmode
, size_stored
,
2536 if (GET_MODE_SIZE (GET_MODE (entry_parm
)) == size
)
2537 PUT_MODE (stack_parm
, GET_MODE (entry_parm
));
2538 set_mem_attributes (stack_parm
, parm
, 1);
2541 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2542 calls that pass values in multiple non-contiguous locations. */
2543 if (REG_P (entry_parm
) || GET_CODE (entry_parm
) == PARALLEL
)
2547 /* Note that we will be storing an integral number of words.
2548 So we have to be careful to ensure that we allocate an
2549 integral number of words. We do this above when we call
2550 assign_stack_local if space was not allocated in the argument
2551 list. If it was, this will not work if PARM_BOUNDARY is not
2552 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2553 if it becomes a problem. Exception is when BLKmode arrives
2554 with arguments not conforming to word_mode. */
2556 if (data
->stack_parm
== 0)
2558 else if (GET_CODE (entry_parm
) == PARALLEL
)
2561 gcc_assert (!size
|| !(PARM_BOUNDARY
% BITS_PER_WORD
));
2563 mem
= validize_mem (stack_parm
);
2565 /* Handle values in multiple non-contiguous locations. */
2566 if (GET_CODE (entry_parm
) == PARALLEL
)
2568 push_to_sequence2 (all
->first_conversion_insn
,
2569 all
->last_conversion_insn
);
2570 emit_group_store (mem
, entry_parm
, data
->passed_type
, size
);
2571 all
->first_conversion_insn
= get_insns ();
2572 all
->last_conversion_insn
= get_last_insn ();
2579 /* If SIZE is that of a mode no bigger than a word, just use
2580 that mode's store operation. */
2581 else if (size
<= UNITS_PER_WORD
)
2583 enum machine_mode mode
2584 = mode_for_size (size
* BITS_PER_UNIT
, MODE_INT
, 0);
2587 #ifdef BLOCK_REG_PADDING
2588 && (size
== UNITS_PER_WORD
2589 || (BLOCK_REG_PADDING (mode
, data
->passed_type
, 1)
2590 != (BYTES_BIG_ENDIAN
? upward
: downward
)))
2596 /* We are really truncating a word_mode value containing
2597 SIZE bytes into a value of mode MODE. If such an
2598 operation requires no actual instructions, we can refer
2599 to the value directly in mode MODE, otherwise we must
2600 start with the register in word_mode and explicitly
2602 if (TRULY_NOOP_TRUNCATION (size
* BITS_PER_UNIT
, BITS_PER_WORD
))
2603 reg
= gen_rtx_REG (mode
, REGNO (entry_parm
));
2606 reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
2607 reg
= convert_to_mode (mode
, copy_to_reg (reg
), 1);
2609 emit_move_insn (change_address (mem
, mode
, 0), reg
);
2612 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
2613 machine must be aligned to the left before storing
2614 to memory. Note that the previous test doesn't
2615 handle all cases (e.g. SIZE == 3). */
2616 else if (size
!= UNITS_PER_WORD
2617 #ifdef BLOCK_REG_PADDING
2618 && (BLOCK_REG_PADDING (mode
, data
->passed_type
, 1)
2626 int by
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
2627 rtx reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
2629 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
,
2630 build_int_cst (NULL_TREE
, by
),
2632 tem
= change_address (mem
, word_mode
, 0);
2633 emit_move_insn (tem
, x
);
2636 move_block_from_reg (REGNO (entry_parm
), mem
,
2637 size_stored
/ UNITS_PER_WORD
);
2640 move_block_from_reg (REGNO (entry_parm
), mem
,
2641 size_stored
/ UNITS_PER_WORD
);
2643 else if (data
->stack_parm
== 0)
2645 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2646 emit_block_move (stack_parm
, data
->entry_parm
, GEN_INT (size
),
2648 all
->first_conversion_insn
= get_insns ();
2649 all
->last_conversion_insn
= get_last_insn ();
2653 data
->stack_parm
= stack_parm
;
2654 SET_DECL_RTL (parm
, stack_parm
);
2657 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
2658 parameter. Get it there. Perform all ABI specified conversions. */
2661 assign_parm_setup_reg (struct assign_parm_data_all
*all
, tree parm
,
2662 struct assign_parm_data_one
*data
)
2665 enum machine_mode promoted_nominal_mode
;
2666 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (parm
));
2667 bool did_conversion
= false;
2669 /* Store the parm in a pseudoregister during the function, but we may
2670 need to do it in a wider mode. */
2672 /* This is not really promoting for a call. However we need to be
2673 consistent with assign_parm_find_data_types and expand_expr_real_1. */
2674 promoted_nominal_mode
2675 = promote_mode (data
->nominal_type
, data
->nominal_mode
, &unsignedp
, 1);
2677 parmreg
= gen_reg_rtx (promoted_nominal_mode
);
2679 if (!DECL_ARTIFICIAL (parm
))
2680 mark_user_reg (parmreg
);
2682 /* If this was an item that we received a pointer to,
2683 set DECL_RTL appropriately. */
2684 if (data
->passed_pointer
)
2686 rtx x
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data
->passed_type
)), parmreg
);
2687 set_mem_attributes (x
, parm
, 1);
2688 SET_DECL_RTL (parm
, x
);
2691 SET_DECL_RTL (parm
, parmreg
);
2693 /* Copy the value into the register. */
2694 if (data
->nominal_mode
!= data
->passed_mode
2695 || promoted_nominal_mode
!= data
->promoted_mode
)
2699 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
2700 mode, by the caller. We now have to convert it to
2701 NOMINAL_MODE, if different. However, PARMREG may be in
2702 a different mode than NOMINAL_MODE if it is being stored
2705 If ENTRY_PARM is a hard register, it might be in a register
2706 not valid for operating in its mode (e.g., an odd-numbered
2707 register for a DFmode). In that case, moves are the only
2708 thing valid, so we can't do a convert from there. This
2709 occurs when the calling sequence allow such misaligned
2712 In addition, the conversion may involve a call, which could
2713 clobber parameters which haven't been copied to pseudo
2714 registers yet. Therefore, we must first copy the parm to
2715 a pseudo reg here, and save the conversion until after all
2716 parameters have been moved. */
2718 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
2720 emit_move_insn (tempreg
, validize_mem (data
->entry_parm
));
2722 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2723 tempreg
= convert_to_mode (data
->nominal_mode
, tempreg
, unsignedp
);
2725 if (GET_CODE (tempreg
) == SUBREG
2726 && GET_MODE (tempreg
) == data
->nominal_mode
2727 && REG_P (SUBREG_REG (tempreg
))
2728 && data
->nominal_mode
== data
->passed_mode
2729 && GET_MODE (SUBREG_REG (tempreg
)) == GET_MODE (data
->entry_parm
)
2730 && GET_MODE_SIZE (GET_MODE (tempreg
))
2731 < GET_MODE_SIZE (GET_MODE (data
->entry_parm
)))
2733 /* The argument is already sign/zero extended, so note it
2735 SUBREG_PROMOTED_VAR_P (tempreg
) = 1;
2736 SUBREG_PROMOTED_UNSIGNED_SET (tempreg
, unsignedp
);
2739 /* TREE_USED gets set erroneously during expand_assignment. */
2740 save_tree_used
= TREE_USED (parm
);
2741 expand_assignment (parm
, make_tree (data
->nominal_type
, tempreg
), false);
2742 TREE_USED (parm
) = save_tree_used
;
2743 all
->first_conversion_insn
= get_insns ();
2744 all
->last_conversion_insn
= get_last_insn ();
2747 did_conversion
= true;
2750 emit_move_insn (parmreg
, validize_mem (data
->entry_parm
));
2752 /* If we were passed a pointer but the actual value can safely live
2753 in a register, put it in one. */
2754 if (data
->passed_pointer
2755 && TYPE_MODE (TREE_TYPE (parm
)) != BLKmode
2756 /* If by-reference argument was promoted, demote it. */
2757 && (TYPE_MODE (TREE_TYPE (parm
)) != GET_MODE (DECL_RTL (parm
))
2758 || use_register_for_decl (parm
)))
2760 /* We can't use nominal_mode, because it will have been set to
2761 Pmode above. We must use the actual mode of the parm. */
2762 parmreg
= gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm
)));
2763 mark_user_reg (parmreg
);
2765 if (GET_MODE (parmreg
) != GET_MODE (DECL_RTL (parm
)))
2767 rtx tempreg
= gen_reg_rtx (GET_MODE (DECL_RTL (parm
)));
2768 int unsigned_p
= TYPE_UNSIGNED (TREE_TYPE (parm
));
2770 push_to_sequence2 (all
->first_conversion_insn
,
2771 all
->last_conversion_insn
);
2772 emit_move_insn (tempreg
, DECL_RTL (parm
));
2773 tempreg
= convert_to_mode (GET_MODE (parmreg
), tempreg
, unsigned_p
);
2774 emit_move_insn (parmreg
, tempreg
);
2775 all
->first_conversion_insn
= get_insns ();
2776 all
->last_conversion_insn
= get_last_insn ();
2779 did_conversion
= true;
2782 emit_move_insn (parmreg
, DECL_RTL (parm
));
2784 SET_DECL_RTL (parm
, parmreg
);
2786 /* STACK_PARM is the pointer, not the parm, and PARMREG is
2788 data
->stack_parm
= NULL
;
2791 /* Mark the register as eliminable if we did no conversion and it was
2792 copied from memory at a fixed offset, and the arg pointer was not
2793 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
2794 offset formed an invalid address, such memory-equivalences as we
2795 make here would screw up life analysis for it. */
2796 if (data
->nominal_mode
== data
->passed_mode
2798 && data
->stack_parm
!= 0
2799 && MEM_P (data
->stack_parm
)
2800 && data
->locate
.offset
.var
== 0
2801 && reg_mentioned_p (virtual_incoming_args_rtx
,
2802 XEXP (data
->stack_parm
, 0)))
2804 rtx linsn
= get_last_insn ();
2807 /* Mark complex types separately. */
2808 if (GET_CODE (parmreg
) == CONCAT
)
2810 enum machine_mode submode
2811 = GET_MODE_INNER (GET_MODE (parmreg
));
2812 int regnor
= REGNO (XEXP (parmreg
, 0));
2813 int regnoi
= REGNO (XEXP (parmreg
, 1));
2814 rtx stackr
= adjust_address_nv (data
->stack_parm
, submode
, 0);
2815 rtx stacki
= adjust_address_nv (data
->stack_parm
, submode
,
2816 GET_MODE_SIZE (submode
));
2818 /* Scan backwards for the set of the real and
2820 for (sinsn
= linsn
; sinsn
!= 0;
2821 sinsn
= prev_nonnote_insn (sinsn
))
2823 set
= single_set (sinsn
);
2827 if (SET_DEST (set
) == regno_reg_rtx
[regnoi
])
2828 set_unique_reg_note (sinsn
, REG_EQUIV
, stacki
);
2829 else if (SET_DEST (set
) == regno_reg_rtx
[regnor
])
2830 set_unique_reg_note (sinsn
, REG_EQUIV
, stackr
);
2833 else if ((set
= single_set (linsn
)) != 0
2834 && SET_DEST (set
) == parmreg
)
2835 set_unique_reg_note (linsn
, REG_EQUIV
, data
->stack_parm
);
2838 /* For pointer data type, suggest pointer register. */
2839 if (POINTER_TYPE_P (TREE_TYPE (parm
)))
2840 mark_reg_pointer (parmreg
,
2841 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
2844 /* A subroutine of assign_parms. Allocate stack space to hold the current
2845 parameter. Get it there. Perform all ABI specified conversions. */
2848 assign_parm_setup_stack (struct assign_parm_data_all
*all
, tree parm
,
2849 struct assign_parm_data_one
*data
)
2851 /* Value must be stored in the stack slot STACK_PARM during function
2853 bool to_conversion
= false;
2855 if (data
->promoted_mode
!= data
->nominal_mode
)
2857 /* Conversion is required. */
2858 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
2860 emit_move_insn (tempreg
, validize_mem (data
->entry_parm
));
2862 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2863 to_conversion
= true;
2865 data
->entry_parm
= convert_to_mode (data
->nominal_mode
, tempreg
,
2866 TYPE_UNSIGNED (TREE_TYPE (parm
)));
2868 if (data
->stack_parm
)
2869 /* ??? This may need a big-endian conversion on sparc64. */
2871 = adjust_address (data
->stack_parm
, data
->nominal_mode
, 0);
2874 if (data
->entry_parm
!= data
->stack_parm
)
2878 if (data
->stack_parm
== 0)
2881 = assign_stack_local (GET_MODE (data
->entry_parm
),
2882 GET_MODE_SIZE (GET_MODE (data
->entry_parm
)),
2883 TYPE_ALIGN (data
->passed_type
));
2884 set_mem_attributes (data
->stack_parm
, parm
, 1);
2887 dest
= validize_mem (data
->stack_parm
);
2888 src
= validize_mem (data
->entry_parm
);
2892 /* Use a block move to handle potentially misaligned entry_parm. */
2894 push_to_sequence2 (all
->first_conversion_insn
,
2895 all
->last_conversion_insn
);
2896 to_conversion
= true;
2898 emit_block_move (dest
, src
,
2899 GEN_INT (int_size_in_bytes (data
->passed_type
)),
2903 emit_move_insn (dest
, src
);
2908 all
->first_conversion_insn
= get_insns ();
2909 all
->last_conversion_insn
= get_last_insn ();
2913 SET_DECL_RTL (parm
, data
->stack_parm
);
2916 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
2917 undo the frobbing that we did in assign_parms_augmented_arg_list. */
2920 assign_parms_unsplit_complex (struct assign_parm_data_all
*all
, tree fnargs
)
2923 tree orig_fnargs
= all
->orig_fnargs
;
2925 for (parm
= orig_fnargs
; parm
; parm
= TREE_CHAIN (parm
))
2927 if (TREE_CODE (TREE_TYPE (parm
)) == COMPLEX_TYPE
2928 && targetm
.calls
.split_complex_arg (TREE_TYPE (parm
)))
2930 rtx tmp
, real
, imag
;
2931 enum machine_mode inner
= GET_MODE_INNER (DECL_MODE (parm
));
2933 real
= DECL_RTL (fnargs
);
2934 imag
= DECL_RTL (TREE_CHAIN (fnargs
));
2935 if (inner
!= GET_MODE (real
))
2937 real
= gen_lowpart_SUBREG (inner
, real
);
2938 imag
= gen_lowpart_SUBREG (inner
, imag
);
2941 if (TREE_ADDRESSABLE (parm
))
2944 HOST_WIDE_INT size
= int_size_in_bytes (TREE_TYPE (parm
));
2946 /* split_complex_arg put the real and imag parts in
2947 pseudos. Move them to memory. */
2948 tmp
= assign_stack_local (DECL_MODE (parm
), size
,
2949 TYPE_ALIGN (TREE_TYPE (parm
)));
2950 set_mem_attributes (tmp
, parm
, 1);
2951 rmem
= adjust_address_nv (tmp
, inner
, 0);
2952 imem
= adjust_address_nv (tmp
, inner
, GET_MODE_SIZE (inner
));
2953 push_to_sequence2 (all
->first_conversion_insn
,
2954 all
->last_conversion_insn
);
2955 emit_move_insn (rmem
, real
);
2956 emit_move_insn (imem
, imag
);
2957 all
->first_conversion_insn
= get_insns ();
2958 all
->last_conversion_insn
= get_last_insn ();
2962 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
2963 SET_DECL_RTL (parm
, tmp
);
2965 real
= DECL_INCOMING_RTL (fnargs
);
2966 imag
= DECL_INCOMING_RTL (TREE_CHAIN (fnargs
));
2967 if (inner
!= GET_MODE (real
))
2969 real
= gen_lowpart_SUBREG (inner
, real
);
2970 imag
= gen_lowpart_SUBREG (inner
, imag
);
2972 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
2973 set_decl_incoming_rtl (parm
, tmp
);
2974 fnargs
= TREE_CHAIN (fnargs
);
2978 SET_DECL_RTL (parm
, DECL_RTL (fnargs
));
2979 set_decl_incoming_rtl (parm
, DECL_INCOMING_RTL (fnargs
));
2981 /* Set MEM_EXPR to the original decl, i.e. to PARM,
2982 instead of the copy of decl, i.e. FNARGS. */
2983 if (DECL_INCOMING_RTL (parm
) && MEM_P (DECL_INCOMING_RTL (parm
)))
2984 set_mem_expr (DECL_INCOMING_RTL (parm
), parm
);
2987 fnargs
= TREE_CHAIN (fnargs
);
2991 /* Assign RTL expressions to the function's parameters. This may involve
2992 copying them into registers and using those registers as the DECL_RTL. */
2995 assign_parms (tree fndecl
)
2997 struct assign_parm_data_all all
;
3000 current_function_internal_arg_pointer
3001 = targetm
.calls
.internal_arg_pointer ();
3003 assign_parms_initialize_all (&all
);
3004 fnargs
= assign_parms_augmented_arg_list (&all
);
3006 for (parm
= fnargs
; parm
; parm
= TREE_CHAIN (parm
))
3008 struct assign_parm_data_one data
;
3010 /* Extract the type of PARM; adjust it according to ABI. */
3011 assign_parm_find_data_types (&all
, parm
, &data
);
3013 /* Early out for errors and void parameters. */
3014 if (data
.passed_mode
== VOIDmode
)
3016 SET_DECL_RTL (parm
, const0_rtx
);
3017 DECL_INCOMING_RTL (parm
) = DECL_RTL (parm
);
3021 if (current_function_stdarg
&& !TREE_CHAIN (parm
))
3022 assign_parms_setup_varargs (&all
, &data
, false);
3024 /* Find out where the parameter arrives in this function. */
3025 assign_parm_find_entry_rtl (&all
, &data
);
3027 /* Find out where stack space for this parameter might be. */
3028 if (assign_parm_is_stack_parm (&all
, &data
))
3030 assign_parm_find_stack_rtl (parm
, &data
);
3031 assign_parm_adjust_entry_rtl (&data
);
3034 /* Record permanently how this parm was passed. */
3035 set_decl_incoming_rtl (parm
, data
.entry_parm
);
3037 /* Update info on where next arg arrives in registers. */
3038 FUNCTION_ARG_ADVANCE (all
.args_so_far
, data
.promoted_mode
,
3039 data
.passed_type
, data
.named_arg
);
3041 assign_parm_adjust_stack_rtl (&data
);
3043 if (assign_parm_setup_block_p (&data
))
3044 assign_parm_setup_block (&all
, parm
, &data
);
3045 else if (data
.passed_pointer
|| use_register_for_decl (parm
))
3046 assign_parm_setup_reg (&all
, parm
, &data
);
3048 assign_parm_setup_stack (&all
, parm
, &data
);
3051 if (targetm
.calls
.split_complex_arg
&& fnargs
!= all
.orig_fnargs
)
3052 assign_parms_unsplit_complex (&all
, fnargs
);
3054 /* Output all parameter conversion instructions (possibly including calls)
3055 now that all parameters have been copied out of hard registers. */
3056 emit_insn (all
.first_conversion_insn
);
3058 /* If we are receiving a struct value address as the first argument, set up
3059 the RTL for the function result. As this might require code to convert
3060 the transmitted address to Pmode, we do this here to ensure that possible
3061 preliminary conversions of the address have been emitted already. */
3062 if (all
.function_result_decl
)
3064 tree result
= DECL_RESULT (current_function_decl
);
3065 rtx addr
= DECL_RTL (all
.function_result_decl
);
3068 if (DECL_BY_REFERENCE (result
))
3072 addr
= convert_memory_address (Pmode
, addr
);
3073 x
= gen_rtx_MEM (DECL_MODE (result
), addr
);
3074 set_mem_attributes (x
, result
, 1);
3076 SET_DECL_RTL (result
, x
);
3079 /* We have aligned all the args, so add space for the pretend args. */
3080 current_function_pretend_args_size
= all
.pretend_args_size
;
3081 all
.stack_args_size
.constant
+= all
.extra_pretend_bytes
;
3082 current_function_args_size
= all
.stack_args_size
.constant
;
3084 /* Adjust function incoming argument size for alignment and
3087 #ifdef REG_PARM_STACK_SPACE
3088 current_function_args_size
= MAX (current_function_args_size
,
3089 REG_PARM_STACK_SPACE (fndecl
));
3092 current_function_args_size
= CEIL_ROUND (current_function_args_size
,
3093 PARM_BOUNDARY
/ BITS_PER_UNIT
);
3095 #ifdef ARGS_GROW_DOWNWARD
3096 current_function_arg_offset_rtx
3097 = (all
.stack_args_size
.var
== 0 ? GEN_INT (-all
.stack_args_size
.constant
)
3098 : expand_expr (size_diffop (all
.stack_args_size
.var
,
3099 size_int (-all
.stack_args_size
.constant
)),
3100 NULL_RTX
, VOIDmode
, 0));
3102 current_function_arg_offset_rtx
= ARGS_SIZE_RTX (all
.stack_args_size
);
3105 /* See how many bytes, if any, of its args a function should try to pop
3108 current_function_pops_args
= RETURN_POPS_ARGS (fndecl
, TREE_TYPE (fndecl
),
3109 current_function_args_size
);
3111 /* For stdarg.h function, save info about
3112 regs and stack space used by the named args. */
3114 current_function_args_info
= all
.args_so_far
;
3116 /* Set the rtx used for the function return value. Put this in its
3117 own variable so any optimizers that need this information don't have
3118 to include tree.h. Do this here so it gets done when an inlined
3119 function gets output. */
3121 current_function_return_rtx
3122 = (DECL_RTL_SET_P (DECL_RESULT (fndecl
))
3123 ? DECL_RTL (DECL_RESULT (fndecl
)) : NULL_RTX
);
3125 /* If scalar return value was computed in a pseudo-reg, or was a named
3126 return value that got dumped to the stack, copy that to the hard
3128 if (DECL_RTL_SET_P (DECL_RESULT (fndecl
)))
3130 tree decl_result
= DECL_RESULT (fndecl
);
3131 rtx decl_rtl
= DECL_RTL (decl_result
);
3133 if (REG_P (decl_rtl
)
3134 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
3135 : DECL_REGISTER (decl_result
))
3139 real_decl_rtl
= targetm
.calls
.function_value (TREE_TYPE (decl_result
),
3141 REG_FUNCTION_VALUE_P (real_decl_rtl
) = 1;
3142 /* The delay slot scheduler assumes that current_function_return_rtx
3143 holds the hard register containing the return value, not a
3144 temporary pseudo. */
3145 current_function_return_rtx
= real_decl_rtl
;
3150 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3151 For all seen types, gimplify their sizes. */
3154 gimplify_parm_type (tree
*tp
, int *walk_subtrees
, void *data
)
3161 if (POINTER_TYPE_P (t
))
3163 else if (TYPE_SIZE (t
) && !TREE_CONSTANT (TYPE_SIZE (t
))
3164 && !TYPE_SIZES_GIMPLIFIED (t
))
3166 gimplify_type_sizes (t
, (tree
*) data
);
3174 /* Gimplify the parameter list for current_function_decl. This involves
3175 evaluating SAVE_EXPRs of variable sized parameters and generating code
3176 to implement callee-copies reference parameters. Returns a list of
3177 statements to add to the beginning of the function, or NULL if nothing
3181 gimplify_parameters (void)
3183 struct assign_parm_data_all all
;
3184 tree fnargs
, parm
, stmts
= NULL
;
3186 assign_parms_initialize_all (&all
);
3187 fnargs
= assign_parms_augmented_arg_list (&all
);
3189 for (parm
= fnargs
; parm
; parm
= TREE_CHAIN (parm
))
3191 struct assign_parm_data_one data
;
3193 /* Extract the type of PARM; adjust it according to ABI. */
3194 assign_parm_find_data_types (&all
, parm
, &data
);
3196 /* Early out for errors and void parameters. */
3197 if (data
.passed_mode
== VOIDmode
|| DECL_SIZE (parm
) == NULL
)
3200 /* Update info on where next arg arrives in registers. */
3201 FUNCTION_ARG_ADVANCE (all
.args_so_far
, data
.promoted_mode
,
3202 data
.passed_type
, data
.named_arg
);
3204 /* ??? Once upon a time variable_size stuffed parameter list
3205 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3206 turned out to be less than manageable in the gimple world.
3207 Now we have to hunt them down ourselves. */
3208 walk_tree_without_duplicates (&data
.passed_type
,
3209 gimplify_parm_type
, &stmts
);
3211 if (!TREE_CONSTANT (DECL_SIZE (parm
)))
3213 gimplify_one_sizepos (&DECL_SIZE (parm
), &stmts
);
3214 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm
), &stmts
);
3217 if (data
.passed_pointer
)
3219 tree type
= TREE_TYPE (data
.passed_type
);
3220 if (reference_callee_copied (&all
.args_so_far
, TYPE_MODE (type
),
3221 type
, data
.named_arg
))
3225 /* For constant sized objects, this is trivial; for
3226 variable-sized objects, we have to play games. */
3227 if (TREE_CONSTANT (DECL_SIZE (parm
)))
3229 local
= create_tmp_var (type
, get_name (parm
));
3230 DECL_IGNORED_P (local
) = 0;
3234 tree ptr_type
, addr
;
3236 ptr_type
= build_pointer_type (type
);
3237 addr
= create_tmp_var (ptr_type
, get_name (parm
));
3238 DECL_IGNORED_P (addr
) = 0;
3239 local
= build_fold_indirect_ref (addr
);
3241 t
= built_in_decls
[BUILT_IN_ALLOCA
];
3242 t
= build_call_expr (t
, 1, DECL_SIZE_UNIT (parm
));
3243 t
= fold_convert (ptr_type
, t
);
3244 t
= build_gimple_modify_stmt (addr
, t
);
3245 gimplify_and_add (t
, &stmts
);
3248 t
= build_gimple_modify_stmt (local
, parm
);
3249 gimplify_and_add (t
, &stmts
);
3251 SET_DECL_VALUE_EXPR (parm
, local
);
3252 DECL_HAS_VALUE_EXPR_P (parm
) = 1;
3260 /* Compute the size and offset from the start of the stacked arguments for a
3261 parm passed in mode PASSED_MODE and with type TYPE.
3263 INITIAL_OFFSET_PTR points to the current offset into the stacked
3266 The starting offset and size for this parm are returned in
3267 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3268 nonzero, the offset is that of stack slot, which is returned in
3269 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3270 padding required from the initial offset ptr to the stack slot.
3272 IN_REGS is nonzero if the argument will be passed in registers. It will
3273 never be set if REG_PARM_STACK_SPACE is not defined.
3275 FNDECL is the function in which the argument was defined.
3277 There are two types of rounding that are done. The first, controlled by
3278 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
3279 list to be aligned to the specific boundary (in bits). This rounding
3280 affects the initial and starting offsets, but not the argument size.
3282 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3283 optionally rounds the size of the parm to PARM_BOUNDARY. The
3284 initial offset is not affected by this rounding, while the size always
3285 is and the starting offset may be. */
3287 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3288 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3289 callers pass in the total size of args so far as
3290 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
3293 locate_and_pad_parm (enum machine_mode passed_mode
, tree type
, int in_regs
,
3294 int partial
, tree fndecl ATTRIBUTE_UNUSED
,
3295 struct args_size
*initial_offset_ptr
,
3296 struct locate_and_pad_arg_data
*locate
)
3299 enum direction where_pad
;
3300 unsigned int boundary
;
3301 int reg_parm_stack_space
= 0;
3302 int part_size_in_regs
;
3304 #ifdef REG_PARM_STACK_SPACE
3305 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
3307 /* If we have found a stack parm before we reach the end of the
3308 area reserved for registers, skip that area. */
3311 if (reg_parm_stack_space
> 0)
3313 if (initial_offset_ptr
->var
)
3315 initial_offset_ptr
->var
3316 = size_binop (MAX_EXPR
, ARGS_SIZE_TREE (*initial_offset_ptr
),
3317 ssize_int (reg_parm_stack_space
));
3318 initial_offset_ptr
->constant
= 0;
3320 else if (initial_offset_ptr
->constant
< reg_parm_stack_space
)
3321 initial_offset_ptr
->constant
= reg_parm_stack_space
;
3324 #endif /* REG_PARM_STACK_SPACE */
3326 part_size_in_regs
= (reg_parm_stack_space
== 0 ? partial
: 0);
3329 = type
? size_in_bytes (type
) : size_int (GET_MODE_SIZE (passed_mode
));
3330 where_pad
= FUNCTION_ARG_PADDING (passed_mode
, type
);
3331 boundary
= FUNCTION_ARG_BOUNDARY (passed_mode
, type
);
3332 locate
->where_pad
= where_pad
;
3333 locate
->boundary
= boundary
;
3335 /* Remember if the outgoing parameter requires extra alignment on the
3336 calling function side. */
3337 if (boundary
> PREFERRED_STACK_BOUNDARY
)
3338 boundary
= PREFERRED_STACK_BOUNDARY
;
3339 if (cfun
->stack_alignment_needed
< boundary
)
3340 cfun
->stack_alignment_needed
= boundary
;
3342 #ifdef ARGS_GROW_DOWNWARD
3343 locate
->slot_offset
.constant
= -initial_offset_ptr
->constant
;
3344 if (initial_offset_ptr
->var
)
3345 locate
->slot_offset
.var
= size_binop (MINUS_EXPR
, ssize_int (0),
3346 initial_offset_ptr
->var
);
3350 if (where_pad
!= none
3351 && (!host_integerp (sizetree
, 1)
3352 || (tree_low_cst (sizetree
, 1) * BITS_PER_UNIT
) % PARM_BOUNDARY
))
3353 s2
= round_up (s2
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3354 SUB_PARM_SIZE (locate
->slot_offset
, s2
);
3357 locate
->slot_offset
.constant
+= part_size_in_regs
;
3360 #ifdef REG_PARM_STACK_SPACE
3361 || REG_PARM_STACK_SPACE (fndecl
) > 0
3364 pad_to_arg_alignment (&locate
->slot_offset
, boundary
,
3365 &locate
->alignment_pad
);
3367 locate
->size
.constant
= (-initial_offset_ptr
->constant
3368 - locate
->slot_offset
.constant
);
3369 if (initial_offset_ptr
->var
)
3370 locate
->size
.var
= size_binop (MINUS_EXPR
,
3371 size_binop (MINUS_EXPR
,
3373 initial_offset_ptr
->var
),
3374 locate
->slot_offset
.var
);
3376 /* Pad_below needs the pre-rounded size to know how much to pad
3378 locate
->offset
= locate
->slot_offset
;
3379 if (where_pad
== downward
)
3380 pad_below (&locate
->offset
, passed_mode
, sizetree
);
3382 #else /* !ARGS_GROW_DOWNWARD */
3384 #ifdef REG_PARM_STACK_SPACE
3385 || REG_PARM_STACK_SPACE (fndecl
) > 0
3388 pad_to_arg_alignment (initial_offset_ptr
, boundary
,
3389 &locate
->alignment_pad
);
3390 locate
->slot_offset
= *initial_offset_ptr
;
3392 #ifdef PUSH_ROUNDING
3393 if (passed_mode
!= BLKmode
)
3394 sizetree
= size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree
)));
3397 /* Pad_below needs the pre-rounded size to know how much to pad below
3398 so this must be done before rounding up. */
3399 locate
->offset
= locate
->slot_offset
;
3400 if (where_pad
== downward
)
3401 pad_below (&locate
->offset
, passed_mode
, sizetree
);
3403 if (where_pad
!= none
3404 && (!host_integerp (sizetree
, 1)
3405 || (tree_low_cst (sizetree
, 1) * BITS_PER_UNIT
) % PARM_BOUNDARY
))
3406 sizetree
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3408 ADD_PARM_SIZE (locate
->size
, sizetree
);
3410 locate
->size
.constant
-= part_size_in_regs
;
3411 #endif /* ARGS_GROW_DOWNWARD */
3414 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
3415 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
3418 pad_to_arg_alignment (struct args_size
*offset_ptr
, int boundary
,
3419 struct args_size
*alignment_pad
)
3421 tree save_var
= NULL_TREE
;
3422 HOST_WIDE_INT save_constant
= 0;
3423 int boundary_in_bytes
= boundary
/ BITS_PER_UNIT
;
3424 HOST_WIDE_INT sp_offset
= STACK_POINTER_OFFSET
;
3426 #ifdef SPARC_STACK_BOUNDARY_HACK
3427 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
3428 the real alignment of %sp. However, when it does this, the
3429 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
3430 if (SPARC_STACK_BOUNDARY_HACK
)
3434 if (boundary
> PARM_BOUNDARY
&& boundary
> STACK_BOUNDARY
)
3436 save_var
= offset_ptr
->var
;
3437 save_constant
= offset_ptr
->constant
;
3440 alignment_pad
->var
= NULL_TREE
;
3441 alignment_pad
->constant
= 0;
3443 if (boundary
> BITS_PER_UNIT
)
3445 if (offset_ptr
->var
)
3447 tree sp_offset_tree
= ssize_int (sp_offset
);
3448 tree offset
= size_binop (PLUS_EXPR
,
3449 ARGS_SIZE_TREE (*offset_ptr
),
3451 #ifdef ARGS_GROW_DOWNWARD
3452 tree rounded
= round_down (offset
, boundary
/ BITS_PER_UNIT
);
3454 tree rounded
= round_up (offset
, boundary
/ BITS_PER_UNIT
);
3457 offset_ptr
->var
= size_binop (MINUS_EXPR
, rounded
, sp_offset_tree
);
3458 /* ARGS_SIZE_TREE includes constant term. */
3459 offset_ptr
->constant
= 0;
3460 if (boundary
> PARM_BOUNDARY
&& boundary
> STACK_BOUNDARY
)
3461 alignment_pad
->var
= size_binop (MINUS_EXPR
, offset_ptr
->var
,
3466 offset_ptr
->constant
= -sp_offset
+
3467 #ifdef ARGS_GROW_DOWNWARD
3468 FLOOR_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
3470 CEIL_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
3472 if (boundary
> PARM_BOUNDARY
&& boundary
> STACK_BOUNDARY
)
3473 alignment_pad
->constant
= offset_ptr
->constant
- save_constant
;
3479 pad_below (struct args_size
*offset_ptr
, enum machine_mode passed_mode
, tree sizetree
)
3481 if (passed_mode
!= BLKmode
)
3483 if (GET_MODE_BITSIZE (passed_mode
) % PARM_BOUNDARY
)
3484 offset_ptr
->constant
3485 += (((GET_MODE_BITSIZE (passed_mode
) + PARM_BOUNDARY
- 1)
3486 / PARM_BOUNDARY
* PARM_BOUNDARY
/ BITS_PER_UNIT
)
3487 - GET_MODE_SIZE (passed_mode
));
3491 if (TREE_CODE (sizetree
) != INTEGER_CST
3492 || (TREE_INT_CST_LOW (sizetree
) * BITS_PER_UNIT
) % PARM_BOUNDARY
)
3494 /* Round the size up to multiple of PARM_BOUNDARY bits. */
3495 tree s2
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3497 ADD_PARM_SIZE (*offset_ptr
, s2
);
3498 SUB_PARM_SIZE (*offset_ptr
, sizetree
);
3504 /* True if register REGNO was alive at a place where `setjmp' was
3505 called and was set more than once or is an argument. Such regs may
3506 be clobbered by `longjmp'. */
3509 regno_clobbered_at_setjmp (bitmap setjmp_crosses
, int regno
)
3511 /* There appear to be cases where some local vars never reach the
3512 backend but have bogus regnos. */
3513 if (regno
>= max_reg_num ())
3516 return ((REG_N_SETS (regno
) > 1
3517 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR
), regno
))
3518 && REGNO_REG_SET_P (setjmp_crosses
, regno
));
3521 /* Walk the tree of blocks describing the binding levels within a
3522 function and warn about variables the might be killed by setjmp or
3523 vfork. This is done after calling flow_analysis before register
3524 allocation since that will clobber the pseudo-regs to hard
3528 setjmp_vars_warning (bitmap setjmp_crosses
, tree block
)
3532 for (decl
= BLOCK_VARS (block
); decl
; decl
= TREE_CHAIN (decl
))
3534 if (TREE_CODE (decl
) == VAR_DECL
3535 && DECL_RTL_SET_P (decl
)
3536 && REG_P (DECL_RTL (decl
))
3537 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
3538 warning (OPT_Wclobbered
, "variable %q+D might be clobbered by"
3539 " %<longjmp%> or %<vfork%>", decl
);
3542 for (sub
= BLOCK_SUBBLOCKS (block
); sub
; sub
= TREE_CHAIN (sub
))
3543 setjmp_vars_warning (setjmp_crosses
, sub
);
3546 /* Do the appropriate part of setjmp_vars_warning
3547 but for arguments instead of local variables. */
3550 setjmp_args_warning (bitmap setjmp_crosses
)
3553 for (decl
= DECL_ARGUMENTS (current_function_decl
);
3554 decl
; decl
= TREE_CHAIN (decl
))
3555 if (DECL_RTL (decl
) != 0
3556 && REG_P (DECL_RTL (decl
))
3557 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
3558 warning (OPT_Wclobbered
,
3559 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
3563 /* Generate warning messages for variables live across setjmp. */
3566 generate_setjmp_warnings (void)
3568 bitmap setjmp_crosses
= regstat_get_setjmp_crosses ();
3570 if (n_basic_blocks
== NUM_FIXED_BLOCKS
3571 || bitmap_empty_p (setjmp_crosses
))
3574 setjmp_vars_warning (setjmp_crosses
, DECL_INITIAL (current_function_decl
));
3575 setjmp_args_warning (setjmp_crosses
);
3579 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
3580 and create duplicate blocks. */
3581 /* ??? Need an option to either create block fragments or to create
3582 abstract origin duplicates of a source block. It really depends
3583 on what optimization has been performed. */
3586 reorder_blocks (void)
3588 tree block
= DECL_INITIAL (current_function_decl
);
3589 VEC(tree
,heap
) *block_stack
;
3591 if (block
== NULL_TREE
)
3594 block_stack
= VEC_alloc (tree
, heap
, 10);
3596 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
3597 clear_block_marks (block
);
3599 /* Prune the old trees away, so that they don't get in the way. */
3600 BLOCK_SUBBLOCKS (block
) = NULL_TREE
;
3601 BLOCK_CHAIN (block
) = NULL_TREE
;
3603 /* Recreate the block tree from the note nesting. */
3604 reorder_blocks_1 (get_insns (), block
, &block_stack
);
3605 BLOCK_SUBBLOCKS (block
) = blocks_nreverse (BLOCK_SUBBLOCKS (block
));
3607 VEC_free (tree
, heap
, block_stack
);
3610 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
3613 clear_block_marks (tree block
)
3617 TREE_ASM_WRITTEN (block
) = 0;
3618 clear_block_marks (BLOCK_SUBBLOCKS (block
));
3619 block
= BLOCK_CHAIN (block
);
3624 reorder_blocks_1 (rtx insns
, tree current_block
, VEC(tree
,heap
) **p_block_stack
)
3628 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
3632 if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_BEG
)
3634 tree block
= NOTE_BLOCK (insn
);
3637 origin
= (BLOCK_FRAGMENT_ORIGIN (block
)
3638 ? BLOCK_FRAGMENT_ORIGIN (block
)
3641 /* If we have seen this block before, that means it now
3642 spans multiple address regions. Create a new fragment. */
3643 if (TREE_ASM_WRITTEN (block
))
3645 tree new_block
= copy_node (block
);
3647 BLOCK_FRAGMENT_ORIGIN (new_block
) = origin
;
3648 BLOCK_FRAGMENT_CHAIN (new_block
)
3649 = BLOCK_FRAGMENT_CHAIN (origin
);
3650 BLOCK_FRAGMENT_CHAIN (origin
) = new_block
;
3652 NOTE_BLOCK (insn
) = new_block
;
3656 BLOCK_SUBBLOCKS (block
) = 0;
3657 TREE_ASM_WRITTEN (block
) = 1;
3658 /* When there's only one block for the entire function,
3659 current_block == block and we mustn't do this, it
3660 will cause infinite recursion. */
3661 if (block
!= current_block
)
3663 if (block
!= origin
)
3664 gcc_assert (BLOCK_SUPERCONTEXT (origin
) == current_block
);
3666 BLOCK_SUPERCONTEXT (block
) = current_block
;
3667 BLOCK_CHAIN (block
) = BLOCK_SUBBLOCKS (current_block
);
3668 BLOCK_SUBBLOCKS (current_block
) = block
;
3669 current_block
= origin
;
3671 VEC_safe_push (tree
, heap
, *p_block_stack
, block
);
3673 else if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_END
)
3675 NOTE_BLOCK (insn
) = VEC_pop (tree
, *p_block_stack
);
3676 BLOCK_SUBBLOCKS (current_block
)
3677 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block
));
3678 current_block
= BLOCK_SUPERCONTEXT (current_block
);
3684 /* Reverse the order of elements in the chain T of blocks,
3685 and return the new head of the chain (old last element). */
3688 blocks_nreverse (tree t
)
3690 tree prev
= 0, decl
, next
;
3691 for (decl
= t
; decl
; decl
= next
)
3693 next
= BLOCK_CHAIN (decl
);
3694 BLOCK_CHAIN (decl
) = prev
;
3700 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
3701 non-NULL, list them all into VECTOR, in a depth-first preorder
3702 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
3706 all_blocks (tree block
, tree
*vector
)
3712 TREE_ASM_WRITTEN (block
) = 0;
3714 /* Record this block. */
3716 vector
[n_blocks
] = block
;
3720 /* Record the subblocks, and their subblocks... */
3721 n_blocks
+= all_blocks (BLOCK_SUBBLOCKS (block
),
3722 vector
? vector
+ n_blocks
: 0);
3723 block
= BLOCK_CHAIN (block
);
3729 /* Return a vector containing all the blocks rooted at BLOCK. The
3730 number of elements in the vector is stored in N_BLOCKS_P. The
3731 vector is dynamically allocated; it is the caller's responsibility
3732 to call `free' on the pointer returned. */
3735 get_block_vector (tree block
, int *n_blocks_p
)
3739 *n_blocks_p
= all_blocks (block
, NULL
);
3740 block_vector
= XNEWVEC (tree
, *n_blocks_p
);
3741 all_blocks (block
, block_vector
);
3743 return block_vector
;
3746 static GTY(()) int next_block_index
= 2;
3748 /* Set BLOCK_NUMBER for all the blocks in FN. */
3751 number_blocks (tree fn
)
3757 /* For SDB and XCOFF debugging output, we start numbering the blocks
3758 from 1 within each function, rather than keeping a running
3760 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
3761 if (write_symbols
== SDB_DEBUG
|| write_symbols
== XCOFF_DEBUG
)
3762 next_block_index
= 1;
3765 block_vector
= get_block_vector (DECL_INITIAL (fn
), &n_blocks
);
3767 /* The top-level BLOCK isn't numbered at all. */
3768 for (i
= 1; i
< n_blocks
; ++i
)
3769 /* We number the blocks from two. */
3770 BLOCK_NUMBER (block_vector
[i
]) = next_block_index
++;
3772 free (block_vector
);
3777 /* If VAR is present in a subblock of BLOCK, return the subblock. */
3780 debug_find_var_in_block_tree (tree var
, tree block
)
3784 for (t
= BLOCK_VARS (block
); t
; t
= TREE_CHAIN (t
))
3788 for (t
= BLOCK_SUBBLOCKS (block
); t
; t
= TREE_CHAIN (t
))
3790 tree ret
= debug_find_var_in_block_tree (var
, t
);
3798 /* Keep track of whether we're in a dummy function context. If we are,
3799 we don't want to invoke the set_current_function hook, because we'll
3800 get into trouble if the hook calls target_reinit () recursively or
3801 when the initial initialization is not yet complete. */
3803 static bool in_dummy_function
;
3805 /* Invoke the target hook when setting cfun. */
3808 invoke_set_current_function_hook (tree fndecl
)
3810 if (!in_dummy_function
)
3811 targetm
.set_current_function (fndecl
);
3814 /* cfun should never be set directly; use this function. */
3817 set_cfun (struct function
*new_cfun
)
3819 if (cfun
!= new_cfun
)
3822 invoke_set_current_function_hook (new_cfun
? new_cfun
->decl
: NULL_TREE
);
3826 /* Keep track of the cfun stack. */
3828 typedef struct function
*function_p
;
3830 DEF_VEC_P(function_p
);
3831 DEF_VEC_ALLOC_P(function_p
,heap
);
3833 /* Initialized with NOGC, making this poisonous to the garbage collector. */
3835 static VEC(function_p
,heap
) *cfun_stack
;
3837 /* Push the current cfun onto the stack, and set cfun to new_cfun. */
3840 push_cfun (struct function
*new_cfun
)
3842 VEC_safe_push (function_p
, heap
, cfun_stack
, cfun
);
3843 set_cfun (new_cfun
);
3846 /* Pop cfun from the stack. */
3851 set_cfun (VEC_pop (function_p
, cfun_stack
));
3854 /* Return value of funcdef and increase it. */
3856 get_next_funcdef_no (void)
3858 return funcdef_no
++;
3861 /* Allocate a function structure for FNDECL and set its contents
3862 to the defaults. Set cfun to the newly-allocated object.
3863 Some of the helper functions invoked during initialization assume
3864 that cfun has already been set. Therefore, assign the new object
3865 directly into cfun and invoke the back end hook explicitly at the
3866 very end, rather than initializing a temporary and calling set_cfun
3871 allocate_struct_function (tree fndecl
)
3874 tree fntype
= fndecl
? TREE_TYPE (fndecl
) : NULL_TREE
;
3876 cfun
= ggc_alloc_cleared (sizeof (struct function
));
3878 cfun
->stack_alignment_needed
= STACK_BOUNDARY
;
3879 cfun
->preferred_stack_boundary
= STACK_BOUNDARY
;
3881 current_function_funcdef_no
= get_next_funcdef_no ();
3883 cfun
->function_frequency
= FUNCTION_FREQUENCY_NORMAL
;
3885 init_eh_for_function ();
3887 lang_hooks
.function
.init (cfun
);
3888 if (init_machine_status
)
3889 cfun
->machine
= (*init_machine_status
) ();
3893 DECL_STRUCT_FUNCTION (fndecl
) = cfun
;
3894 cfun
->decl
= fndecl
;
3896 result
= DECL_RESULT (fndecl
);
3897 if (aggregate_value_p (result
, fndecl
))
3899 #ifdef PCC_STATIC_STRUCT_RETURN
3900 current_function_returns_pcc_struct
= 1;
3902 current_function_returns_struct
= 1;
3905 current_function_stdarg
3907 && TYPE_ARG_TYPES (fntype
) != 0
3908 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype
)))
3909 != void_type_node
));
3911 /* Assume all registers in stdarg functions need to be saved. */
3912 cfun
->va_list_gpr_size
= VA_LIST_MAX_GPR_SIZE
;
3913 cfun
->va_list_fpr_size
= VA_LIST_MAX_FPR_SIZE
;
3916 invoke_set_current_function_hook (fndecl
);
3919 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
3920 instead of just setting it. */
3923 push_struct_function (tree fndecl
)
3925 VEC_safe_push (function_p
, heap
, cfun_stack
, cfun
);
3926 allocate_struct_function (fndecl
);
3929 /* Reset cfun, and other non-struct-function variables to defaults as
3930 appropriate for emitting rtl at the start of a function. */
3933 prepare_function_start (void)
3936 init_varasm_status (cfun
);
3939 cse_not_expected
= ! optimize
;
3941 /* Caller save not needed yet. */
3942 caller_save_needed
= 0;
3944 /* We haven't done register allocation yet. */
3947 /* Indicate that we have not instantiated virtual registers yet. */
3948 virtuals_instantiated
= 0;
3950 /* Indicate that we want CONCATs now. */
3951 generating_concat_p
= 1;
3953 /* Indicate we have no need of a frame pointer yet. */
3954 frame_pointer_needed
= 0;
3957 /* Initialize the rtl expansion mechanism so that we can do simple things
3958 like generate sequences. This is used to provide a context during global
3959 initialization of some passes. You must call expand_dummy_function_end
3960 to exit this context. */
3963 init_dummy_function_start (void)
3965 gcc_assert (!in_dummy_function
);
3966 in_dummy_function
= true;
3967 push_struct_function (NULL_TREE
);
3968 prepare_function_start ();
3971 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
3972 and initialize static variables for generating RTL for the statements
3976 init_function_start (tree subr
)
3978 if (subr
&& DECL_STRUCT_FUNCTION (subr
))
3979 set_cfun (DECL_STRUCT_FUNCTION (subr
));
3981 allocate_struct_function (subr
);
3982 prepare_function_start ();
3984 /* Warn if this value is an aggregate type,
3985 regardless of which calling convention we are using for it. */
3986 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr
))))
3987 warning (OPT_Waggregate_return
, "function returns an aggregate");
3990 /* Make sure all values used by the optimization passes have sane
3993 init_function_for_compilation (void)
3997 /* No prologue/epilogue insns yet. Make sure that these vectors are
3999 gcc_assert (VEC_length (int, prologue
) == 0);
4000 gcc_assert (VEC_length (int, epilogue
) == 0);
4001 gcc_assert (VEC_length (int, sibcall_epilogue
) == 0);
4005 struct tree_opt_pass pass_init_function
=
4009 init_function_for_compilation
, /* execute */
4012 0, /* static_pass_number */
4014 0, /* properties_required */
4015 0, /* properties_provided */
4016 0, /* properties_destroyed */
4017 0, /* todo_flags_start */
4018 0, /* todo_flags_finish */
4024 expand_main_function (void)
4026 #if (defined(INVOKE__main) \
4027 || (!defined(HAS_INIT_SECTION) \
4028 && !defined(INIT_SECTION_ASM_OP) \
4029 && !defined(INIT_ARRAY_SECTION_ASM_OP)))
4030 emit_library_call (init_one_libfunc (NAME__MAIN
), LCT_NORMAL
, VOIDmode
, 0);
4034 /* Expand code to initialize the stack_protect_guard. This is invoked at
4035 the beginning of a function to be protected. */
4037 #ifndef HAVE_stack_protect_set
4038 # define HAVE_stack_protect_set 0
4039 # define gen_stack_protect_set(x,y) (gcc_unreachable (), NULL_RTX)
4043 stack_protect_prologue (void)
4045 tree guard_decl
= targetm
.stack_protect_guard ();
4048 /* Avoid expand_expr here, because we don't want guard_decl pulled
4049 into registers unless absolutely necessary. And we know that
4050 cfun->stack_protect_guard is a local stack slot, so this skips
4052 x
= validize_mem (DECL_RTL (cfun
->stack_protect_guard
));
4053 y
= validize_mem (DECL_RTL (guard_decl
));
4055 /* Allow the target to copy from Y to X without leaking Y into a
4057 if (HAVE_stack_protect_set
)
4059 rtx insn
= gen_stack_protect_set (x
, y
);
4067 /* Otherwise do a straight move. */
4068 emit_move_insn (x
, y
);
4071 /* Expand code to verify the stack_protect_guard. This is invoked at
4072 the end of a function to be protected. */
4074 #ifndef HAVE_stack_protect_test
4075 # define HAVE_stack_protect_test 0
4076 # define gen_stack_protect_test(x, y, z) (gcc_unreachable (), NULL_RTX)
4080 stack_protect_epilogue (void)
4082 tree guard_decl
= targetm
.stack_protect_guard ();
4083 rtx label
= gen_label_rtx ();
4086 /* Avoid expand_expr here, because we don't want guard_decl pulled
4087 into registers unless absolutely necessary. And we know that
4088 cfun->stack_protect_guard is a local stack slot, so this skips
4090 x
= validize_mem (DECL_RTL (cfun
->stack_protect_guard
));
4091 y
= validize_mem (DECL_RTL (guard_decl
));
4093 /* Allow the target to compare Y with X without leaking either into
4095 switch (HAVE_stack_protect_test
!= 0)
4098 tmp
= gen_stack_protect_test (x
, y
, label
);
4107 emit_cmp_and_jump_insns (x
, y
, EQ
, NULL_RTX
, ptr_mode
, 1, label
);
4111 /* The noreturn predictor has been moved to the tree level. The rtl-level
4112 predictors estimate this branch about 20%, which isn't enough to get
4113 things moved out of line. Since this is the only extant case of adding
4114 a noreturn function at the rtl level, it doesn't seem worth doing ought
4115 except adding the prediction by hand. */
4116 tmp
= get_last_insn ();
4118 predict_insn_def (tmp
, PRED_NORETURN
, TAKEN
);
4120 expand_expr_stmt (targetm
.stack_protect_fail ());
4124 /* Start the RTL for a new function, and set variables used for
4126 SUBR is the FUNCTION_DECL node.
4127 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4128 the function's parameters, which must be run at any return statement. */
4131 expand_function_start (tree subr
)
4133 /* Make sure volatile mem refs aren't considered
4134 valid operands of arithmetic insns. */
4135 init_recog_no_volatile ();
4137 current_function_profile
4139 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr
));
4141 current_function_limit_stack
4142 = (stack_limit_rtx
!= NULL_RTX
&& ! DECL_NO_LIMIT_STACK (subr
));
4144 /* Make the label for return statements to jump to. Do not special
4145 case machines with special return instructions -- they will be
4146 handled later during jump, ifcvt, or epilogue creation. */
4147 return_label
= gen_label_rtx ();
4149 /* Initialize rtx used to return the value. */
4150 /* Do this before assign_parms so that we copy the struct value address
4151 before any library calls that assign parms might generate. */
4153 /* Decide whether to return the value in memory or in a register. */
4154 if (aggregate_value_p (DECL_RESULT (subr
), subr
))
4156 /* Returning something that won't go in a register. */
4157 rtx value_address
= 0;
4159 #ifdef PCC_STATIC_STRUCT_RETURN
4160 if (current_function_returns_pcc_struct
)
4162 int size
= int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr
)));
4163 value_address
= assemble_static_space (size
);
4168 rtx sv
= targetm
.calls
.struct_value_rtx (TREE_TYPE (subr
), 2);
4169 /* Expect to be passed the address of a place to store the value.
4170 If it is passed as an argument, assign_parms will take care of
4174 value_address
= gen_reg_rtx (Pmode
);
4175 emit_move_insn (value_address
, sv
);
4180 rtx x
= value_address
;
4181 if (!DECL_BY_REFERENCE (DECL_RESULT (subr
)))
4183 x
= gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr
)), x
);
4184 set_mem_attributes (x
, DECL_RESULT (subr
), 1);
4186 SET_DECL_RTL (DECL_RESULT (subr
), x
);
4189 else if (DECL_MODE (DECL_RESULT (subr
)) == VOIDmode
)
4190 /* If return mode is void, this decl rtl should not be used. */
4191 SET_DECL_RTL (DECL_RESULT (subr
), NULL_RTX
);
4194 /* Compute the return values into a pseudo reg, which we will copy
4195 into the true return register after the cleanups are done. */
4196 tree return_type
= TREE_TYPE (DECL_RESULT (subr
));
4197 if (TYPE_MODE (return_type
) != BLKmode
4198 && targetm
.calls
.return_in_msb (return_type
))
4199 /* expand_function_end will insert the appropriate padding in
4200 this case. Use the return value's natural (unpadded) mode
4201 within the function proper. */
4202 SET_DECL_RTL (DECL_RESULT (subr
),
4203 gen_reg_rtx (TYPE_MODE (return_type
)));
4206 /* In order to figure out what mode to use for the pseudo, we
4207 figure out what the mode of the eventual return register will
4208 actually be, and use that. */
4209 rtx hard_reg
= hard_function_value (return_type
, subr
, 0, 1);
4211 /* Structures that are returned in registers are not
4212 aggregate_value_p, so we may see a PARALLEL or a REG. */
4213 if (REG_P (hard_reg
))
4214 SET_DECL_RTL (DECL_RESULT (subr
),
4215 gen_reg_rtx (GET_MODE (hard_reg
)));
4218 gcc_assert (GET_CODE (hard_reg
) == PARALLEL
);
4219 SET_DECL_RTL (DECL_RESULT (subr
), gen_group_rtx (hard_reg
));
4223 /* Set DECL_REGISTER flag so that expand_function_end will copy the
4224 result to the real return register(s). */
4225 DECL_REGISTER (DECL_RESULT (subr
)) = 1;
4228 /* Initialize rtx for parameters and local variables.
4229 In some cases this requires emitting insns. */
4230 assign_parms (subr
);
4232 /* If function gets a static chain arg, store it. */
4233 if (cfun
->static_chain_decl
)
4235 tree parm
= cfun
->static_chain_decl
;
4236 rtx local
= gen_reg_rtx (Pmode
);
4238 set_decl_incoming_rtl (parm
, static_chain_incoming_rtx
);
4239 SET_DECL_RTL (parm
, local
);
4240 mark_reg_pointer (local
, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
4242 emit_move_insn (local
, static_chain_incoming_rtx
);
4245 /* If the function receives a non-local goto, then store the
4246 bits we need to restore the frame pointer. */
4247 if (cfun
->nonlocal_goto_save_area
)
4252 /* ??? We need to do this save early. Unfortunately here is
4253 before the frame variable gets declared. Help out... */
4254 expand_var (TREE_OPERAND (cfun
->nonlocal_goto_save_area
, 0));
4256 t_save
= build4 (ARRAY_REF
, ptr_type_node
,
4257 cfun
->nonlocal_goto_save_area
,
4258 integer_zero_node
, NULL_TREE
, NULL_TREE
);
4259 r_save
= expand_expr (t_save
, NULL_RTX
, VOIDmode
, EXPAND_WRITE
);
4260 r_save
= convert_memory_address (Pmode
, r_save
);
4262 emit_move_insn (r_save
, virtual_stack_vars_rtx
);
4263 update_nonlocal_goto_save_area ();
4266 /* The following was moved from init_function_start.
4267 The move is supposed to make sdb output more accurate. */
4268 /* Indicate the beginning of the function body,
4269 as opposed to parm setup. */
4270 emit_note (NOTE_INSN_FUNCTION_BEG
);
4272 gcc_assert (NOTE_P (get_last_insn ()));
4274 parm_birth_insn
= get_last_insn ();
4276 if (current_function_profile
)
4279 PROFILE_HOOK (current_function_funcdef_no
);
4283 /* After the display initializations is where the stack checking
4285 if(flag_stack_check
)
4286 stack_check_probe_note
= emit_note (NOTE_INSN_DELETED
);
4288 /* Make sure there is a line number after the function entry setup code. */
4289 force_next_line_note ();
4292 /* Undo the effects of init_dummy_function_start. */
4294 expand_dummy_function_end (void)
4296 gcc_assert (in_dummy_function
);
4298 /* End any sequences that failed to be closed due to syntax errors. */
4299 while (in_sequence_p ())
4302 /* Outside function body, can't compute type's actual size
4303 until next function's body starts. */
4305 free_after_parsing (cfun
);
4306 free_after_compilation (cfun
);
4308 in_dummy_function
= false;
4311 /* Call DOIT for each hard register used as a return value from
4312 the current function. */
4315 diddle_return_value (void (*doit
) (rtx
, void *), void *arg
)
4317 rtx outgoing
= current_function_return_rtx
;
4322 if (REG_P (outgoing
))
4323 (*doit
) (outgoing
, arg
);
4324 else if (GET_CODE (outgoing
) == PARALLEL
)
4328 for (i
= 0; i
< XVECLEN (outgoing
, 0); i
++)
4330 rtx x
= XEXP (XVECEXP (outgoing
, 0, i
), 0);
4332 if (REG_P (x
) && REGNO (x
) < FIRST_PSEUDO_REGISTER
)
4339 do_clobber_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
4341 emit_insn (gen_rtx_CLOBBER (VOIDmode
, reg
));
4345 clobber_return_register (void)
4347 diddle_return_value (do_clobber_return_reg
, NULL
);
4349 /* In case we do use pseudo to return value, clobber it too. */
4350 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
4352 tree decl_result
= DECL_RESULT (current_function_decl
);
4353 rtx decl_rtl
= DECL_RTL (decl_result
);
4354 if (REG_P (decl_rtl
) && REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
)
4356 do_clobber_return_reg (decl_rtl
, NULL
);
4362 do_use_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
4364 emit_insn (gen_rtx_USE (VOIDmode
, reg
));
4368 use_return_register (void)
4370 diddle_return_value (do_use_return_reg
, NULL
);
4373 /* Possibly warn about unused parameters. */
4375 do_warn_unused_parameter (tree fn
)
4379 for (decl
= DECL_ARGUMENTS (fn
);
4380 decl
; decl
= TREE_CHAIN (decl
))
4381 if (!TREE_USED (decl
) && TREE_CODE (decl
) == PARM_DECL
4382 && DECL_NAME (decl
) && !DECL_ARTIFICIAL (decl
)
4383 && !TREE_NO_WARNING (decl
))
4384 warning (OPT_Wunused_parameter
, "unused parameter %q+D", decl
);
4387 static GTY(()) rtx initial_trampoline
;
4389 /* Generate RTL for the end of the current function. */
4392 expand_function_end (void)
4396 /* If arg_pointer_save_area was referenced only from a nested
4397 function, we will not have initialized it yet. Do that now. */
4398 if (arg_pointer_save_area
&& ! cfun
->arg_pointer_save_area_init
)
4399 get_arg_pointer_save_area (cfun
);
4401 /* If we are doing stack checking and this function makes calls,
4402 do a stack probe at the start of the function to ensure we have enough
4403 space for another stack frame. */
4404 if (flag_stack_check
&& ! STACK_CHECK_BUILTIN
)
4408 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
4412 probe_stack_range (STACK_CHECK_PROTECT
,
4413 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE
));
4416 emit_insn_before (seq
, stack_check_probe_note
);
4421 /* End any sequences that failed to be closed due to syntax errors. */
4422 while (in_sequence_p ())
4425 clear_pending_stack_adjust ();
4426 do_pending_stack_adjust ();
4428 /* Output a linenumber for the end of the function.
4429 SDB depends on this. */
4430 force_next_line_note ();
4431 set_curr_insn_source_location (input_location
);
4433 /* Before the return label (if any), clobber the return
4434 registers so that they are not propagated live to the rest of
4435 the function. This can only happen with functions that drop
4436 through; if there had been a return statement, there would
4437 have either been a return rtx, or a jump to the return label.
4439 We delay actual code generation after the current_function_value_rtx
4441 clobber_after
= get_last_insn ();
4443 /* Output the label for the actual return from the function. */
4444 emit_label (return_label
);
4446 if (USING_SJLJ_EXCEPTIONS
)
4448 /* Let except.c know where it should emit the call to unregister
4449 the function context for sjlj exceptions. */
4450 if (flag_exceptions
)
4451 sjlj_emit_function_exit_after (get_last_insn ());
4455 /* We want to ensure that instructions that may trap are not
4456 moved into the epilogue by scheduling, because we don't
4457 always emit unwind information for the epilogue. */
4458 if (flag_non_call_exceptions
)
4459 emit_insn (gen_blockage ());
4462 /* If this is an implementation of throw, do what's necessary to
4463 communicate between __builtin_eh_return and the epilogue. */
4464 expand_eh_return ();
4466 /* If scalar return value was computed in a pseudo-reg, or was a named
4467 return value that got dumped to the stack, copy that to the hard
4469 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
4471 tree decl_result
= DECL_RESULT (current_function_decl
);
4472 rtx decl_rtl
= DECL_RTL (decl_result
);
4474 if (REG_P (decl_rtl
)
4475 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
4476 : DECL_REGISTER (decl_result
))
4478 rtx real_decl_rtl
= current_function_return_rtx
;
4480 /* This should be set in assign_parms. */
4481 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl
));
4483 /* If this is a BLKmode structure being returned in registers,
4484 then use the mode computed in expand_return. Note that if
4485 decl_rtl is memory, then its mode may have been changed,
4486 but that current_function_return_rtx has not. */
4487 if (GET_MODE (real_decl_rtl
) == BLKmode
)
4488 PUT_MODE (real_decl_rtl
, GET_MODE (decl_rtl
));
4490 /* If a non-BLKmode return value should be padded at the least
4491 significant end of the register, shift it left by the appropriate
4492 amount. BLKmode results are handled using the group load/store
4494 if (TYPE_MODE (TREE_TYPE (decl_result
)) != BLKmode
4495 && targetm
.calls
.return_in_msb (TREE_TYPE (decl_result
)))
4497 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl
),
4498 REGNO (real_decl_rtl
)),
4500 shift_return_value (GET_MODE (decl_rtl
), true, real_decl_rtl
);
4502 /* If a named return value dumped decl_return to memory, then
4503 we may need to re-do the PROMOTE_MODE signed/unsigned
4505 else if (GET_MODE (real_decl_rtl
) != GET_MODE (decl_rtl
))
4507 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (decl_result
));
4509 if (targetm
.calls
.promote_function_return (TREE_TYPE (current_function_decl
)))
4510 promote_mode (TREE_TYPE (decl_result
), GET_MODE (decl_rtl
),
4513 convert_move (real_decl_rtl
, decl_rtl
, unsignedp
);
4515 else if (GET_CODE (real_decl_rtl
) == PARALLEL
)
4517 /* If expand_function_start has created a PARALLEL for decl_rtl,
4518 move the result to the real return registers. Otherwise, do
4519 a group load from decl_rtl for a named return. */
4520 if (GET_CODE (decl_rtl
) == PARALLEL
)
4521 emit_group_move (real_decl_rtl
, decl_rtl
);
4523 emit_group_load (real_decl_rtl
, decl_rtl
,
4524 TREE_TYPE (decl_result
),
4525 int_size_in_bytes (TREE_TYPE (decl_result
)));
4527 /* In the case of complex integer modes smaller than a word, we'll
4528 need to generate some non-trivial bitfield insertions. Do that
4529 on a pseudo and not the hard register. */
4530 else if (GET_CODE (decl_rtl
) == CONCAT
4531 && GET_MODE_CLASS (GET_MODE (decl_rtl
)) == MODE_COMPLEX_INT
4532 && GET_MODE_BITSIZE (GET_MODE (decl_rtl
)) <= BITS_PER_WORD
)
4534 int old_generating_concat_p
;
4537 old_generating_concat_p
= generating_concat_p
;
4538 generating_concat_p
= 0;
4539 tmp
= gen_reg_rtx (GET_MODE (decl_rtl
));
4540 generating_concat_p
= old_generating_concat_p
;
4542 emit_move_insn (tmp
, decl_rtl
);
4543 emit_move_insn (real_decl_rtl
, tmp
);
4546 emit_move_insn (real_decl_rtl
, decl_rtl
);
4550 /* If returning a structure, arrange to return the address of the value
4551 in a place where debuggers expect to find it.
4553 If returning a structure PCC style,
4554 the caller also depends on this value.
4555 And current_function_returns_pcc_struct is not necessarily set. */
4556 if (current_function_returns_struct
4557 || current_function_returns_pcc_struct
)
4559 rtx value_address
= DECL_RTL (DECL_RESULT (current_function_decl
));
4560 tree type
= TREE_TYPE (DECL_RESULT (current_function_decl
));
4563 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl
)))
4564 type
= TREE_TYPE (type
);
4566 value_address
= XEXP (value_address
, 0);
4568 outgoing
= targetm
.calls
.function_value (build_pointer_type (type
),
4569 current_function_decl
, true);
4571 /* Mark this as a function return value so integrate will delete the
4572 assignment and USE below when inlining this function. */
4573 REG_FUNCTION_VALUE_P (outgoing
) = 1;
4575 /* The address may be ptr_mode and OUTGOING may be Pmode. */
4576 value_address
= convert_memory_address (GET_MODE (outgoing
),
4579 emit_move_insn (outgoing
, value_address
);
4581 /* Show return register used to hold result (in this case the address
4583 current_function_return_rtx
= outgoing
;
4586 /* Emit the actual code to clobber return register. */
4591 clobber_return_register ();
4592 expand_naked_return ();
4596 emit_insn_after (seq
, clobber_after
);
4599 /* Output the label for the naked return from the function. */
4600 emit_label (naked_return_label
);
4602 /* @@@ This is a kludge. We want to ensure that instructions that
4603 may trap are not moved into the epilogue by scheduling, because
4604 we don't always emit unwind information for the epilogue. */
4605 if (! USING_SJLJ_EXCEPTIONS
&& flag_non_call_exceptions
)
4606 emit_insn (gen_blockage ());
4608 /* If stack protection is enabled for this function, check the guard. */
4609 if (cfun
->stack_protect_guard
)
4610 stack_protect_epilogue ();
4612 /* If we had calls to alloca, and this machine needs
4613 an accurate stack pointer to exit the function,
4614 insert some code to save and restore the stack pointer. */
4615 if (! EXIT_IGNORE_STACK
4616 && current_function_calls_alloca
)
4620 emit_stack_save (SAVE_FUNCTION
, &tem
, parm_birth_insn
);
4621 emit_stack_restore (SAVE_FUNCTION
, tem
, NULL_RTX
);
4624 /* ??? This should no longer be necessary since stupid is no longer with
4625 us, but there are some parts of the compiler (eg reload_combine, and
4626 sh mach_dep_reorg) that still try and compute their own lifetime info
4627 instead of using the general framework. */
4628 use_return_register ();
4632 get_arg_pointer_save_area (struct function
*f
)
4634 rtx ret
= f
->x_arg_pointer_save_area
;
4638 ret
= assign_stack_local_1 (Pmode
, GET_MODE_SIZE (Pmode
), 0, f
);
4639 f
->x_arg_pointer_save_area
= ret
;
4642 if (f
== cfun
&& ! f
->arg_pointer_save_area_init
)
4646 /* Save the arg pointer at the beginning of the function. The
4647 generated stack slot may not be a valid memory address, so we
4648 have to check it and fix it if necessary. */
4650 emit_move_insn (validize_mem (ret
), virtual_incoming_args_rtx
);
4654 push_topmost_sequence ();
4655 emit_insn_after (seq
, entry_of_function ());
4656 pop_topmost_sequence ();
4662 /* Extend a vector that records the INSN_UIDs of INSNS
4663 (a list of one or more insns). */
4666 record_insns (rtx insns
, VEC(int,heap
) **vecp
)
4670 for (tmp
= insns
; tmp
!= NULL_RTX
; tmp
= NEXT_INSN (tmp
))
4671 VEC_safe_push (int, heap
, *vecp
, INSN_UID (tmp
));
4674 /* Set the locator of the insn chain starting at INSN to LOC. */
4676 set_insn_locators (rtx insn
, int loc
)
4678 while (insn
!= NULL_RTX
)
4681 INSN_LOCATOR (insn
) = loc
;
4682 insn
= NEXT_INSN (insn
);
4686 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
4687 be running after reorg, SEQUENCE rtl is possible. */
4690 contains (const_rtx insn
, VEC(int,heap
) **vec
)
4694 if (NONJUMP_INSN_P (insn
)
4695 && GET_CODE (PATTERN (insn
)) == SEQUENCE
)
4698 for (i
= XVECLEN (PATTERN (insn
), 0) - 1; i
>= 0; i
--)
4699 for (j
= VEC_length (int, *vec
) - 1; j
>= 0; --j
)
4700 if (INSN_UID (XVECEXP (PATTERN (insn
), 0, i
))
4701 == VEC_index (int, *vec
, j
))
4707 for (j
= VEC_length (int, *vec
) - 1; j
>= 0; --j
)
4708 if (INSN_UID (insn
) == VEC_index (int, *vec
, j
))
4715 prologue_epilogue_contains (const_rtx insn
)
4717 if (contains (insn
, &prologue
))
4719 if (contains (insn
, &epilogue
))
4725 sibcall_epilogue_contains (const_rtx insn
)
4727 if (sibcall_epilogue
)
4728 return contains (insn
, &sibcall_epilogue
);
4733 /* Insert gen_return at the end of block BB. This also means updating
4734 block_for_insn appropriately. */
4737 emit_return_into_block (basic_block bb
)
4739 emit_jump_insn_after (gen_return (), BB_END (bb
));
4741 #endif /* HAVE_return */
4743 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
4745 /* These functions convert the epilogue into a variant that does not
4746 modify the stack pointer. This is used in cases where a function
4747 returns an object whose size is not known until it is computed.
4748 The called function leaves the object on the stack, leaves the
4749 stack depressed, and returns a pointer to the object.
4751 What we need to do is track all modifications and references to the
4752 stack pointer, deleting the modifications and changing the
4753 references to point to the location the stack pointer would have
4754 pointed to had the modifications taken place.
4756 These functions need to be portable so we need to make as few
4757 assumptions about the epilogue as we can. However, the epilogue
4758 basically contains three things: instructions to reset the stack
4759 pointer, instructions to reload registers, possibly including the
4760 frame pointer, and an instruction to return to the caller.
4762 We must be sure of what a relevant epilogue insn is doing. We also
4763 make no attempt to validate the insns we make since if they are
4764 invalid, we probably can't do anything valid. The intent is that
4765 these routines get "smarter" as more and more machines start to use
4766 them and they try operating on different epilogues.
4768 We use the following structure to track what the part of the
4769 epilogue that we've already processed has done. We keep two copies
4770 of the SP equivalence, one for use during the insn we are
4771 processing and one for use in the next insn. The difference is
4772 because one part of a PARALLEL may adjust SP and the other may use
4777 rtx sp_equiv_reg
; /* REG that SP is set from, perhaps SP. */
4778 HOST_WIDE_INT sp_offset
; /* Offset from SP_EQUIV_REG of present SP. */
4779 rtx new_sp_equiv_reg
; /* REG to be used at end of insn. */
4780 HOST_WIDE_INT new_sp_offset
; /* Offset to be used at end of insn. */
4781 rtx equiv_reg_src
; /* If nonzero, the value that SP_EQUIV_REG
4782 should be set to once we no longer need
4784 rtx const_equiv
[FIRST_PSEUDO_REGISTER
]; /* Any known constant equivalences
4788 static void handle_epilogue_set (rtx
, struct epi_info
*);
4789 static void update_epilogue_consts (rtx
, const_rtx
, void *);
4790 static void emit_equiv_load (struct epi_info
*);
4792 /* Modify INSN, a list of one or more insns that is part of the epilogue, to
4793 no modifications to the stack pointer. Return the new list of insns. */
4796 keep_stack_depressed (rtx insns
)
4799 struct epi_info info
;
4802 /* If the epilogue is just a single instruction, it must be OK as is. */
4803 if (NEXT_INSN (insns
) == NULL_RTX
)
4806 /* Otherwise, start a sequence, initialize the information we have, and
4807 process all the insns we were given. */
4810 info
.sp_equiv_reg
= stack_pointer_rtx
;
4812 info
.equiv_reg_src
= 0;
4814 for (j
= 0; j
< FIRST_PSEUDO_REGISTER
; j
++)
4815 info
.const_equiv
[j
] = 0;
4819 while (insn
!= NULL_RTX
)
4821 next
= NEXT_INSN (insn
);
4830 /* If this insn references the register that SP is equivalent to and
4831 we have a pending load to that register, we must force out the load
4832 first and then indicate we no longer know what SP's equivalent is. */
4833 if (info
.equiv_reg_src
!= 0
4834 && reg_referenced_p (info
.sp_equiv_reg
, PATTERN (insn
)))
4836 emit_equiv_load (&info
);
4837 info
.sp_equiv_reg
= 0;
4840 info
.new_sp_equiv_reg
= info
.sp_equiv_reg
;
4841 info
.new_sp_offset
= info
.sp_offset
;
4843 /* If this is a (RETURN) and the return address is on the stack,
4844 update the address and change to an indirect jump. */
4845 if (GET_CODE (PATTERN (insn
)) == RETURN
4846 || (GET_CODE (PATTERN (insn
)) == PARALLEL
4847 && GET_CODE (XVECEXP (PATTERN (insn
), 0, 0)) == RETURN
))
4849 rtx retaddr
= INCOMING_RETURN_ADDR_RTX
;
4851 HOST_WIDE_INT offset
= 0;
4852 rtx jump_insn
, jump_set
;
4854 /* If the return address is in a register, we can emit the insn
4855 unchanged. Otherwise, it must be a MEM and we see what the
4856 base register and offset are. In any case, we have to emit any
4857 pending load to the equivalent reg of SP, if any. */
4858 if (REG_P (retaddr
))
4860 emit_equiv_load (&info
);
4868 gcc_assert (MEM_P (retaddr
));
4870 ret_ptr
= XEXP (retaddr
, 0);
4872 if (REG_P (ret_ptr
))
4874 base
= gen_rtx_REG (Pmode
, REGNO (ret_ptr
));
4879 gcc_assert (GET_CODE (ret_ptr
) == PLUS
4880 && REG_P (XEXP (ret_ptr
, 0))
4881 && GET_CODE (XEXP (ret_ptr
, 1)) == CONST_INT
);
4882 base
= gen_rtx_REG (Pmode
, REGNO (XEXP (ret_ptr
, 0)));
4883 offset
= INTVAL (XEXP (ret_ptr
, 1));
4887 /* If the base of the location containing the return pointer
4888 is SP, we must update it with the replacement address. Otherwise,
4889 just build the necessary MEM. */
4890 retaddr
= plus_constant (base
, offset
);
4891 if (base
== stack_pointer_rtx
)
4892 retaddr
= simplify_replace_rtx (retaddr
, stack_pointer_rtx
,
4893 plus_constant (info
.sp_equiv_reg
,
4896 retaddr
= gen_rtx_MEM (Pmode
, retaddr
);
4897 MEM_NOTRAP_P (retaddr
) = 1;
4899 /* If there is a pending load to the equivalent register for SP
4900 and we reference that register, we must load our address into
4901 a scratch register and then do that load. */
4902 if (info
.equiv_reg_src
4903 && reg_overlap_mentioned_p (info
.equiv_reg_src
, retaddr
))
4908 for (regno
= 0; regno
< FIRST_PSEUDO_REGISTER
; regno
++)
4909 if (HARD_REGNO_MODE_OK (regno
, Pmode
)
4910 && !fixed_regs
[regno
]
4911 && TEST_HARD_REG_BIT (regs_invalidated_by_call
, regno
)
4913 (DF_LR_IN (EXIT_BLOCK_PTR
), regno
)
4914 && !refers_to_regno_p (regno
,
4915 end_hard_regno (Pmode
, regno
),
4916 info
.equiv_reg_src
, NULL
)
4917 && info
.const_equiv
[regno
] == 0)
4920 gcc_assert (regno
< FIRST_PSEUDO_REGISTER
);
4922 reg
= gen_rtx_REG (Pmode
, regno
);
4923 emit_move_insn (reg
, retaddr
);
4927 emit_equiv_load (&info
);
4928 jump_insn
= emit_jump_insn (gen_indirect_jump (retaddr
));
4930 /* Show the SET in the above insn is a RETURN. */
4931 jump_set
= single_set (jump_insn
);
4932 gcc_assert (jump_set
);
4933 SET_IS_RETURN_P (jump_set
) = 1;
4936 /* If SP is not mentioned in the pattern and its equivalent register, if
4937 any, is not modified, just emit it. Otherwise, if neither is set,
4938 replace the reference to SP and emit the insn. If none of those are
4939 true, handle each SET individually. */
4940 else if (!reg_mentioned_p (stack_pointer_rtx
, PATTERN (insn
))
4941 && (info
.sp_equiv_reg
== stack_pointer_rtx
4942 || !reg_set_p (info
.sp_equiv_reg
, insn
)))
4944 else if (! reg_set_p (stack_pointer_rtx
, insn
)
4945 && (info
.sp_equiv_reg
== stack_pointer_rtx
4946 || !reg_set_p (info
.sp_equiv_reg
, insn
)))
4950 changed
= validate_replace_rtx (stack_pointer_rtx
,
4951 plus_constant (info
.sp_equiv_reg
,
4954 gcc_assert (changed
);
4958 else if (GET_CODE (PATTERN (insn
)) == SET
)
4959 handle_epilogue_set (PATTERN (insn
), &info
);
4960 else if (GET_CODE (PATTERN (insn
)) == PARALLEL
)
4962 for (j
= 0; j
< XVECLEN (PATTERN (insn
), 0); j
++)
4963 if (GET_CODE (XVECEXP (PATTERN (insn
), 0, j
)) == SET
)
4964 handle_epilogue_set (XVECEXP (PATTERN (insn
), 0, j
), &info
);
4969 info
.sp_equiv_reg
= info
.new_sp_equiv_reg
;
4970 info
.sp_offset
= info
.new_sp_offset
;
4972 /* Now update any constants this insn sets. */
4973 note_stores (PATTERN (insn
), update_epilogue_consts
, &info
);
4977 insns
= get_insns ();
4982 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
4983 structure that contains information about what we've seen so far. We
4984 process this SET by either updating that data or by emitting one or
4988 handle_epilogue_set (rtx set
, struct epi_info
*p
)
4990 /* First handle the case where we are setting SP. Record what it is being
4991 set from, which we must be able to determine */
4992 if (reg_set_p (stack_pointer_rtx
, set
))
4994 gcc_assert (SET_DEST (set
) == stack_pointer_rtx
);
4996 if (GET_CODE (SET_SRC (set
)) == PLUS
)
4998 p
->new_sp_equiv_reg
= XEXP (SET_SRC (set
), 0);
4999 if (GET_CODE (XEXP (SET_SRC (set
), 1)) == CONST_INT
)
5000 p
->new_sp_offset
= INTVAL (XEXP (SET_SRC (set
), 1));
5003 gcc_assert (REG_P (XEXP (SET_SRC (set
), 1))
5004 && (REGNO (XEXP (SET_SRC (set
), 1))
5005 < FIRST_PSEUDO_REGISTER
)
5006 && p
->const_equiv
[REGNO (XEXP (SET_SRC (set
), 1))]);
5008 = INTVAL (p
->const_equiv
[REGNO (XEXP (SET_SRC (set
), 1))]);
5012 p
->new_sp_equiv_reg
= SET_SRC (set
), p
->new_sp_offset
= 0;
5014 /* If we are adjusting SP, we adjust from the old data. */
5015 if (p
->new_sp_equiv_reg
== stack_pointer_rtx
)
5017 p
->new_sp_equiv_reg
= p
->sp_equiv_reg
;
5018 p
->new_sp_offset
+= p
->sp_offset
;
5021 gcc_assert (p
->new_sp_equiv_reg
&& REG_P (p
->new_sp_equiv_reg
));
5026 /* Next handle the case where we are setting SP's equivalent
5027 register. We must not already have a value to set it to. We
5028 could update, but there seems little point in handling that case.
5029 Note that we have to allow for the case where we are setting the
5030 register set in the previous part of a PARALLEL inside a single
5031 insn. But use the old offset for any updates within this insn.
5032 We must allow for the case where the register is being set in a
5033 different (usually wider) mode than Pmode). */
5034 else if (p
->new_sp_equiv_reg
!= 0 && reg_set_p (p
->new_sp_equiv_reg
, set
))
5036 gcc_assert (!p
->equiv_reg_src
5037 && REG_P (p
->new_sp_equiv_reg
)
5038 && REG_P (SET_DEST (set
))
5039 && (GET_MODE_BITSIZE (GET_MODE (SET_DEST (set
)))
5041 && REGNO (p
->new_sp_equiv_reg
) == REGNO (SET_DEST (set
)));
5043 = simplify_replace_rtx (SET_SRC (set
), stack_pointer_rtx
,
5044 plus_constant (p
->sp_equiv_reg
,
5048 /* Otherwise, replace any references to SP in the insn to its new value
5049 and emit the insn. */
5052 SET_SRC (set
) = simplify_replace_rtx (SET_SRC (set
), stack_pointer_rtx
,
5053 plus_constant (p
->sp_equiv_reg
,
5055 SET_DEST (set
) = simplify_replace_rtx (SET_DEST (set
), stack_pointer_rtx
,
5056 plus_constant (p
->sp_equiv_reg
,
5062 /* Update the tracking information for registers set to constants. */
5065 update_epilogue_consts (rtx dest
, const_rtx x
, void *data
)
5067 struct epi_info
*p
= (struct epi_info
*) data
;
5070 if (!REG_P (dest
) || REGNO (dest
) >= FIRST_PSEUDO_REGISTER
)
5073 /* If we are either clobbering a register or doing a partial set,
5074 show we don't know the value. */
5075 else if (GET_CODE (x
) == CLOBBER
|| ! rtx_equal_p (dest
, SET_DEST (x
)))
5076 p
->const_equiv
[REGNO (dest
)] = 0;
5078 /* If we are setting it to a constant, record that constant. */
5079 else if (GET_CODE (SET_SRC (x
)) == CONST_INT
)
5080 p
->const_equiv
[REGNO (dest
)] = SET_SRC (x
);
5082 /* If this is a binary operation between a register we have been tracking
5083 and a constant, see if we can compute a new constant value. */
5084 else if (ARITHMETIC_P (SET_SRC (x
))
5085 && REG_P (XEXP (SET_SRC (x
), 0))
5086 && REGNO (XEXP (SET_SRC (x
), 0)) < FIRST_PSEUDO_REGISTER
5087 && p
->const_equiv
[REGNO (XEXP (SET_SRC (x
), 0))] != 0
5088 && GET_CODE (XEXP (SET_SRC (x
), 1)) == CONST_INT
5089 && 0 != (new = simplify_binary_operation
5090 (GET_CODE (SET_SRC (x
)), GET_MODE (dest
),
5091 p
->const_equiv
[REGNO (XEXP (SET_SRC (x
), 0))],
5092 XEXP (SET_SRC (x
), 1)))
5093 && GET_CODE (new) == CONST_INT
)
5094 p
->const_equiv
[REGNO (dest
)] = new;
5096 /* Otherwise, we can't do anything with this value. */
5098 p
->const_equiv
[REGNO (dest
)] = 0;
5101 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
5104 emit_equiv_load (struct epi_info
*p
)
5106 if (p
->equiv_reg_src
!= 0)
5108 rtx dest
= p
->sp_equiv_reg
;
5110 if (GET_MODE (p
->equiv_reg_src
) != GET_MODE (dest
))
5111 dest
= gen_rtx_REG (GET_MODE (p
->equiv_reg_src
),
5112 REGNO (p
->sp_equiv_reg
));
5114 emit_move_insn (dest
, p
->equiv_reg_src
);
5115 p
->equiv_reg_src
= 0;
5120 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
5121 this into place with notes indicating where the prologue ends and where
5122 the epilogue begins. Update the basic block information when possible. */
5125 thread_prologue_and_epilogue_insns (void)
5129 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
5132 #if defined (HAVE_epilogue) || defined(HAVE_return)
5133 rtx epilogue_end
= NULL_RTX
;
5137 #ifdef HAVE_prologue
5141 seq
= gen_prologue ();
5144 /* Insert an explicit USE for the frame pointer
5145 if the profiling is on and the frame pointer is required. */
5146 if (current_function_profile
&& frame_pointer_needed
)
5147 emit_insn (gen_rtx_USE (VOIDmode
, hard_frame_pointer_rtx
));
5149 /* Retain a map of the prologue insns. */
5150 record_insns (seq
, &prologue
);
5151 emit_note (NOTE_INSN_PROLOGUE_END
);
5153 #ifndef PROFILE_BEFORE_PROLOGUE
5154 /* Ensure that instructions are not moved into the prologue when
5155 profiling is on. The call to the profiling routine can be
5156 emitted within the live range of a call-clobbered register. */
5157 if (current_function_profile
)
5158 emit_insn (gen_blockage ());
5163 set_insn_locators (seq
, prologue_locator
);
5165 /* Can't deal with multiple successors of the entry block
5166 at the moment. Function should always have at least one
5168 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR
));
5170 insert_insn_on_edge (seq
, single_succ_edge (ENTRY_BLOCK_PTR
));
5175 /* If the exit block has no non-fake predecessors, we don't need
5177 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5178 if ((e
->flags
& EDGE_FAKE
) == 0)
5184 if (optimize
&& HAVE_return
)
5186 /* If we're allowed to generate a simple return instruction,
5187 then by definition we don't need a full epilogue. Examine
5188 the block that falls through to EXIT. If it does not
5189 contain any code, examine its predecessors and try to
5190 emit (conditional) return instructions. */
5195 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5196 if (e
->flags
& EDGE_FALLTHRU
)
5202 /* Verify that there are no active instructions in the last block. */
5203 label
= BB_END (last
);
5204 while (label
&& !LABEL_P (label
))
5206 if (active_insn_p (label
))
5208 label
= PREV_INSN (label
);
5211 if (BB_HEAD (last
) == label
&& LABEL_P (label
))
5215 for (ei2
= ei_start (last
->preds
); (e
= ei_safe_edge (ei2
)); )
5217 basic_block bb
= e
->src
;
5220 if (bb
== ENTRY_BLOCK_PTR
)
5227 if (!JUMP_P (jump
) || JUMP_LABEL (jump
) != label
)
5233 /* If we have an unconditional jump, we can replace that
5234 with a simple return instruction. */
5235 if (simplejump_p (jump
))
5237 emit_return_into_block (bb
);
5241 /* If we have a conditional jump, we can try to replace
5242 that with a conditional return instruction. */
5243 else if (condjump_p (jump
))
5245 if (! redirect_jump (jump
, 0, 0))
5251 /* If this block has only one successor, it both jumps
5252 and falls through to the fallthru block, so we can't
5254 if (single_succ_p (bb
))
5266 /* Fix up the CFG for the successful change we just made. */
5267 redirect_edge_succ (e
, EXIT_BLOCK_PTR
);
5270 /* Emit a return insn for the exit fallthru block. Whether
5271 this is still reachable will be determined later. */
5273 emit_barrier_after (BB_END (last
));
5274 emit_return_into_block (last
);
5275 epilogue_end
= BB_END (last
);
5276 single_succ_edge (last
)->flags
&= ~EDGE_FALLTHRU
;
5281 /* Find the edge that falls through to EXIT. Other edges may exist
5282 due to RETURN instructions, but those don't need epilogues.
5283 There really shouldn't be a mixture -- either all should have
5284 been converted or none, however... */
5286 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5287 if (e
->flags
& EDGE_FALLTHRU
)
5292 #ifdef HAVE_epilogue
5296 epilogue_end
= emit_note (NOTE_INSN_EPILOGUE_BEG
);
5298 seq
= gen_epilogue ();
5300 #ifdef INCOMING_RETURN_ADDR_RTX
5301 /* If this function returns with the stack depressed and we can support
5302 it, massage the epilogue to actually do that. */
5303 if (TREE_CODE (TREE_TYPE (current_function_decl
)) == FUNCTION_TYPE
5304 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl
)))
5305 seq
= keep_stack_depressed (seq
);
5308 emit_jump_insn (seq
);
5310 /* Retain a map of the epilogue insns. */
5311 record_insns (seq
, &epilogue
);
5312 set_insn_locators (seq
, epilogue_locator
);
5317 insert_insn_on_edge (seq
, e
);
5325 if (! next_active_insn (BB_END (e
->src
)))
5327 /* We have a fall-through edge to the exit block, the source is not
5328 at the end of the function, and there will be an assembler epilogue
5329 at the end of the function.
5330 We can't use force_nonfallthru here, because that would try to
5331 use return. Inserting a jump 'by hand' is extremely messy, so
5332 we take advantage of cfg_layout_finalize using
5333 fixup_fallthru_exit_predecessor. */
5334 cfg_layout_initialize (0);
5335 FOR_EACH_BB (cur_bb
)
5336 if (cur_bb
->index
>= NUM_FIXED_BLOCKS
5337 && cur_bb
->next_bb
->index
>= NUM_FIXED_BLOCKS
)
5338 cur_bb
->aux
= cur_bb
->next_bb
;
5339 cfg_layout_finalize ();
5345 commit_edge_insertions ();
5347 /* The epilogue insns we inserted may cause the exit edge to no longer
5349 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5351 if (((e
->flags
& EDGE_FALLTHRU
) != 0)
5352 && returnjump_p (BB_END (e
->src
)))
5353 e
->flags
&= ~EDGE_FALLTHRU
;
5357 #ifdef HAVE_sibcall_epilogue
5358 /* Emit sibling epilogues before any sibling call sites. */
5359 for (ei
= ei_start (EXIT_BLOCK_PTR
->preds
); (e
= ei_safe_edge (ei
)); )
5361 basic_block bb
= e
->src
;
5362 rtx insn
= BB_END (bb
);
5365 || ! SIBLING_CALL_P (insn
))
5372 emit_insn (gen_sibcall_epilogue ());
5376 /* Retain a map of the epilogue insns. Used in life analysis to
5377 avoid getting rid of sibcall epilogue insns. Do this before we
5378 actually emit the sequence. */
5379 record_insns (seq
, &sibcall_epilogue
);
5380 set_insn_locators (seq
, epilogue_locator
);
5382 emit_insn_before (seq
, insn
);
5387 #ifdef HAVE_epilogue
5392 /* Similarly, move any line notes that appear after the epilogue.
5393 There is no need, however, to be quite so anal about the existence
5394 of such a note. Also possibly move
5395 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
5397 for (insn
= epilogue_end
; insn
; insn
= next
)
5399 next
= NEXT_INSN (insn
);
5401 && (NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
))
5402 reorder_insns (insn
, insn
, PREV_INSN (epilogue_end
));
5407 /* Threading the prologue and epilogue changes the artificial refs
5408 in the entry and exit blocks. */
5409 epilogue_completed
= 1;
5410 df_update_entry_exit_and_calls ();
5413 /* Reposition the prologue-end and epilogue-begin notes after instruction
5414 scheduling and delayed branch scheduling. */
5417 reposition_prologue_and_epilogue_notes (void)
5419 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
5420 rtx insn
, last
, note
;
5423 if ((len
= VEC_length (int, prologue
)) > 0)
5427 /* Scan from the beginning until we reach the last prologue insn.
5428 We apparently can't depend on basic_block_{head,end} after
5430 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
5434 if (NOTE_KIND (insn
) == NOTE_INSN_PROLOGUE_END
)
5437 else if (contains (insn
, &prologue
))
5447 /* Find the prologue-end note if we haven't already, and
5448 move it to just after the last prologue insn. */
5451 for (note
= last
; (note
= NEXT_INSN (note
));)
5453 && NOTE_KIND (note
) == NOTE_INSN_PROLOGUE_END
)
5457 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
5459 last
= NEXT_INSN (last
);
5460 reorder_insns (note
, note
, last
);
5464 if ((len
= VEC_length (int, epilogue
)) > 0)
5468 /* Scan from the end until we reach the first epilogue insn.
5469 We apparently can't depend on basic_block_{head,end} after
5471 for (insn
= get_last_insn (); insn
; insn
= PREV_INSN (insn
))
5475 if (NOTE_KIND (insn
) == NOTE_INSN_EPILOGUE_BEG
)
5478 else if (contains (insn
, &epilogue
))
5488 /* Find the epilogue-begin note if we haven't already, and
5489 move it to just before the first epilogue insn. */
5492 for (note
= insn
; (note
= PREV_INSN (note
));)
5494 && NOTE_KIND (note
) == NOTE_INSN_EPILOGUE_BEG
)
5498 if (PREV_INSN (last
) != note
)
5499 reorder_insns (note
, note
, PREV_INSN (last
));
5502 #endif /* HAVE_prologue or HAVE_epilogue */
5505 /* Returns the name of the current function. */
5507 current_function_name (void)
5509 return lang_hooks
.decl_printable_name (cfun
->decl
, 2);
5512 /* Returns the raw (mangled) name of the current function. */
5514 current_function_assembler_name (void)
5516 return IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (cfun
->decl
));
5521 rest_of_handle_check_leaf_regs (void)
5523 #ifdef LEAF_REGISTERS
5524 current_function_uses_only_leaf_regs
5525 = optimize
> 0 && only_leaf_regs_used () && leaf_function_p ();
5530 /* Insert a TYPE into the used types hash table of CFUN. */
5532 used_types_insert_helper (tree type
, struct function
*func
)
5534 if (type
!= NULL
&& func
!= NULL
)
5538 if (func
->used_types_hash
== NULL
)
5539 func
->used_types_hash
= htab_create_ggc (37, htab_hash_pointer
,
5540 htab_eq_pointer
, NULL
);
5541 slot
= htab_find_slot (func
->used_types_hash
, type
, INSERT
);
5547 /* Given a type, insert it into the used hash table in cfun. */
5549 used_types_insert (tree t
)
5551 while (POINTER_TYPE_P (t
) || TREE_CODE (t
) == ARRAY_TYPE
)
5553 t
= TYPE_MAIN_VARIANT (t
);
5554 if (debug_info_level
> DINFO_LEVEL_NONE
)
5555 used_types_insert_helper (t
, cfun
);
5558 struct tree_opt_pass pass_leaf_regs
=
5562 rest_of_handle_check_leaf_regs
, /* execute */
5565 0, /* static_pass_number */
5567 0, /* properties_required */
5568 0, /* properties_provided */
5569 0, /* properties_destroyed */
5570 0, /* todo_flags_start */
5571 0, /* todo_flags_finish */
5576 rest_of_handle_thread_prologue_and_epilogue (void)
5579 cleanup_cfg (CLEANUP_EXPENSIVE
);
5580 /* On some machines, the prologue and epilogue code, or parts thereof,
5581 can be represented as RTL. Doing so lets us schedule insns between
5582 it and the rest of the code and also allows delayed branch
5583 scheduling to operate in the epilogue. */
5585 thread_prologue_and_epilogue_insns ();
5589 struct tree_opt_pass pass_thread_prologue_and_epilogue
=
5591 "pro_and_epilogue", /* name */
5593 rest_of_handle_thread_prologue_and_epilogue
, /* execute */
5596 0, /* static_pass_number */
5597 TV_THREAD_PROLOGUE_AND_EPILOGUE
, /* tv_id */
5598 0, /* properties_required */
5599 0, /* properties_provided */
5600 0, /* properties_destroyed */
5601 TODO_verify_flow
, /* todo_flags_start */
5604 TODO_df_finish
| TODO_verify_rtl_sharing
|
5605 TODO_ggc_collect
, /* todo_flags_finish */
5610 /* This mini-pass fixes fall-out from SSA in asm statements that have
5611 in-out constraints. Say you start with
5614 asm ("": "+mr" (inout));
5617 which is transformed very early to use explicit output and match operands:
5620 asm ("": "=mr" (inout) : "0" (inout));
5623 Or, after SSA and copyprop,
5625 asm ("": "=mr" (inout_2) : "0" (inout_1));
5628 Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
5629 they represent two separate values, so they will get different pseudo
5630 registers during expansion. Then, since the two operands need to match
5631 per the constraints, but use different pseudo registers, reload can
5632 only register a reload for these operands. But reloads can only be
5633 satisfied by hardregs, not by memory, so we need a register for this
5634 reload, just because we are presented with non-matching operands.
5635 So, even though we allow memory for this operand, no memory can be
5636 used for it, just because the two operands don't match. This can
5637 cause reload failures on register-starved targets.
5639 So it's a symptom of reload not being able to use memory for reloads
5640 or, alternatively it's also a symptom of both operands not coming into
5641 reload as matching (in which case the pseudo could go to memory just
5642 fine, as the alternative allows it, and no reload would be necessary).
5643 We fix the latter problem here, by transforming
5645 asm ("": "=mr" (inout_2) : "0" (inout_1));
5650 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
5653 match_asm_constraints_1 (rtx insn
, rtx
*p_sets
, int noutputs
)
5656 bool changed
= false;
5657 rtx op
= SET_SRC (p_sets
[0]);
5658 int ninputs
= ASM_OPERANDS_INPUT_LENGTH (op
);
5659 rtvec inputs
= ASM_OPERANDS_INPUT_VEC (op
);
5661 for (i
= 0; i
< ninputs
; i
++)
5663 rtx input
, output
, insns
;
5664 const char *constraint
= ASM_OPERANDS_INPUT_CONSTRAINT (op
, i
);
5668 match
= strtoul (constraint
, &end
, 10);
5669 if (end
== constraint
)
5672 gcc_assert (match
< noutputs
);
5673 output
= SET_DEST (p_sets
[match
]);
5674 input
= RTVEC_ELT (inputs
, i
);
5675 /* Only do the transformation for pseudos. */
5676 if (! REG_P (output
)
5677 || rtx_equal_p (output
, input
)
5678 || (GET_MODE (input
) != VOIDmode
5679 && GET_MODE (input
) != GET_MODE (output
)))
5682 /* We can't do anything if the output is also used as input,
5683 as we're going to overwrite it. */
5684 for (j
= 0; j
< ninputs
; j
++)
5685 if (reg_overlap_mentioned_p (output
, RTVEC_ELT (inputs
, j
)))
5691 emit_move_insn (output
, input
);
5692 insns
= get_insns ();
5694 emit_insn_before (insns
, insn
);
5696 /* Now replace all mentions of the input with output. We can't
5697 just replace the occurence in inputs[i], as the register might
5698 also be used in some other input (or even in an address of an
5699 output), which would mean possibly increasing the number of
5700 inputs by one (namely 'output' in addition), which might pose
5701 a too complicated problem for reload to solve. E.g. this situation:
5703 asm ("" : "=r" (output), "=m" (input) : "0" (input))
5705 Here 'input' is used in two occurences as input (once for the
5706 input operand, once for the address in the second output operand).
5707 If we would replace only the occurence of the input operand (to
5708 make the matching) we would be left with this:
5711 asm ("" : "=r" (output), "=m" (input) : "0" (output))
5713 Now we suddenly have two different input values (containing the same
5714 value, but different pseudos) where we formerly had only one.
5715 With more complicated asms this might lead to reload failures
5716 which wouldn't have happen without this pass. So, iterate over
5717 all operands and replace all occurences of the register used. */
5718 for (j
= 0; j
< noutputs
; j
++)
5719 if (!rtx_equal_p (SET_DEST (p_sets
[j
]), input
)
5720 && reg_overlap_mentioned_p (input
, SET_DEST (p_sets
[j
])))
5721 SET_DEST (p_sets
[j
]) = replace_rtx (SET_DEST (p_sets
[j
]),
5723 for (j
= 0; j
< ninputs
; j
++)
5724 if (reg_overlap_mentioned_p (input
, RTVEC_ELT (inputs
, j
)))
5725 RTVEC_ELT (inputs
, j
) = replace_rtx (RTVEC_ELT (inputs
, j
),
5732 df_insn_rescan (insn
);
5736 rest_of_match_asm_constraints (void)
5739 rtx insn
, pat
, *p_sets
;
5742 if (!cfun
->has_asm_statement
)
5745 df_set_flags (DF_DEFER_INSN_RESCAN
);
5748 FOR_BB_INSNS (bb
, insn
)
5753 pat
= PATTERN (insn
);
5754 if (GET_CODE (pat
) == PARALLEL
)
5755 p_sets
= &XVECEXP (pat
, 0, 0), noutputs
= XVECLEN (pat
, 0);
5756 else if (GET_CODE (pat
) == SET
)
5757 p_sets
= &PATTERN (insn
), noutputs
= 1;
5761 if (GET_CODE (*p_sets
) == SET
5762 && GET_CODE (SET_SRC (*p_sets
)) == ASM_OPERANDS
)
5763 match_asm_constraints_1 (insn
, p_sets
, noutputs
);
5767 return TODO_df_finish
;
5770 struct tree_opt_pass pass_match_asm_constraints
=
5772 "asmcons", /* name */
5774 rest_of_match_asm_constraints
, /* execute */
5777 0, /* static_pass_number */
5779 0, /* properties_required */
5780 0, /* properties_provided */
5781 0, /* properties_destroyed */
5782 0, /* todo_flags_start */
5783 TODO_dump_func
, /* todo_flags_finish */
5788 #include "gt-function.h"