1 /* Expands front end tree to back end RTL for GNU C-Compiler
2 Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000 Free Software Foundation, Inc.
5 This file is part of GNU CC.
7 GNU CC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GNU CC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU CC; see the file COPYING. If not, write to
19 the Free Software Foundation, 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
23 /* This file handles the generation of rtl code from tree structure
24 at the level of the function as a whole.
25 It creates the rtl expressions for parameters and auto variables
26 and has full responsibility for allocating stack slots.
28 `expand_function_start' is called at the beginning of a function,
29 before the function body is parsed, and `expand_function_end' is
30 called after parsing the body.
32 Call `assign_stack_local' to allocate a stack slot for a local variable.
33 This is usually done during the RTL generation for the function body,
34 but it can also be done in the reload pass when a pseudo-register does
35 not get a hard register.
37 Call `put_var_into_stack' when you learn, belatedly, that a variable
38 previously given a pseudo-register must in fact go in the stack.
39 This function changes the DECL_RTL to be a stack slot instead of a reg
40 then scans all the RTL instructions so far generated to correct them. */
49 #include "insn-flags.h"
51 #include "insn-codes.h"
53 #include "hard-reg-set.h"
54 #include "insn-config.h"
57 #include "basic-block.h"
64 #ifndef ACCUMULATE_OUTGOING_ARGS
65 #define ACCUMULATE_OUTGOING_ARGS 0
68 #ifndef TRAMPOLINE_ALIGNMENT
69 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
72 #ifndef LOCAL_ALIGNMENT
73 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
76 #if !defined (PREFERRED_STACK_BOUNDARY) && defined (STACK_BOUNDARY)
77 #define PREFERRED_STACK_BOUNDARY STACK_BOUNDARY
80 /* Some systems use __main in a way incompatible with its use in gcc, in these
81 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
82 give the same symbol without quotes for an alternative entry point. You
83 must define both, or neither. */
85 #define NAME__MAIN "__main"
86 #define SYMBOL__MAIN __main
89 /* Round a value to the lowest integer less than it that is a multiple of
90 the required alignment. Avoid using division in case the value is
91 negative. Assume the alignment is a power of two. */
92 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
94 /* Similar, but round to the next highest integer that meets the
96 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
98 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
99 during rtl generation. If they are different register numbers, this is
100 always true. It may also be true if
101 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
102 generation. See fix_lexical_addr for details. */
104 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
105 #define NEED_SEPARATE_AP
108 /* Nonzero if function being compiled doesn't contain any calls
109 (ignoring the prologue and epilogue). This is set prior to
110 local register allocation and is valid for the remaining
112 int current_function_is_leaf
;
114 /* Nonzero if function being compiled doesn't contain any instructions
115 that can throw an exception. This is set prior to final. */
117 int current_function_nothrow
;
119 /* Nonzero if function being compiled doesn't modify the stack pointer
120 (ignoring the prologue and epilogue). This is only valid after
121 life_analysis has run. */
122 int current_function_sp_is_unchanging
;
124 /* Nonzero if the function being compiled is a leaf function which only
125 uses leaf registers. This is valid after reload (specifically after
126 sched2) and is useful only if the port defines LEAF_REGISTERS. */
127 int current_function_uses_only_leaf_regs
;
129 /* Nonzero once virtual register instantiation has been done.
130 assign_stack_local uses frame_pointer_rtx when this is nonzero. */
131 static int virtuals_instantiated
;
133 /* These variables hold pointers to functions to
134 save and restore machine-specific data,
135 in push_function_context and pop_function_context. */
136 void (*init_machine_status
) PARAMS ((struct function
*));
137 void (*save_machine_status
) PARAMS ((struct function
*));
138 void (*restore_machine_status
) PARAMS ((struct function
*));
139 void (*mark_machine_status
) PARAMS ((struct function
*));
140 void (*free_machine_status
) PARAMS ((struct function
*));
142 /* Likewise, but for language-specific data. */
143 void (*init_lang_status
) PARAMS ((struct function
*));
144 void (*save_lang_status
) PARAMS ((struct function
*));
145 void (*restore_lang_status
) PARAMS ((struct function
*));
146 void (*mark_lang_status
) PARAMS ((struct function
*));
147 void (*free_lang_status
) PARAMS ((struct function
*));
149 /* The FUNCTION_DECL for an inline function currently being expanded. */
150 tree inline_function_decl
;
152 /* The currently compiled function. */
153 struct function
*cfun
= 0;
155 /* Global list of all compiled functions. */
156 struct function
*all_functions
= 0;
158 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
159 static varray_type prologue
;
160 static varray_type epilogue
;
162 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
164 static varray_type sibcall_epilogue
;
166 /* In order to evaluate some expressions, such as function calls returning
167 structures in memory, we need to temporarily allocate stack locations.
168 We record each allocated temporary in the following structure.
170 Associated with each temporary slot is a nesting level. When we pop up
171 one level, all temporaries associated with the previous level are freed.
172 Normally, all temporaries are freed after the execution of the statement
173 in which they were created. However, if we are inside a ({...}) grouping,
174 the result may be in a temporary and hence must be preserved. If the
175 result could be in a temporary, we preserve it if we can determine which
176 one it is in. If we cannot determine which temporary may contain the
177 result, all temporaries are preserved. A temporary is preserved by
178 pretending it was allocated at the previous nesting level.
180 Automatic variables are also assigned temporary slots, at the nesting
181 level where they are defined. They are marked a "kept" so that
182 free_temp_slots will not free them. */
186 /* Points to next temporary slot. */
187 struct temp_slot
*next
;
188 /* The rtx to used to reference the slot. */
190 /* The rtx used to represent the address if not the address of the
191 slot above. May be an EXPR_LIST if multiple addresses exist. */
193 /* The alignment (in bits) of the slot. */
195 /* The size, in units, of the slot. */
197 /* The alias set for the slot. If the alias set is zero, we don't
198 know anything about the alias set of the slot. We must only
199 reuse a slot if it is assigned an object of the same alias set.
200 Otherwise, the rest of the compiler may assume that the new use
201 of the slot cannot alias the old use of the slot, which is
202 false. If the slot has alias set zero, then we can't reuse the
203 slot at all, since we have no idea what alias set may have been
204 imposed on the memory. For example, if the stack slot is the
205 call frame for an inline functioned, we have no idea what alias
206 sets will be assigned to various pieces of the call frame. */
208 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
210 /* Non-zero if this temporary is currently in use. */
212 /* Non-zero if this temporary has its address taken. */
214 /* Nesting level at which this slot is being used. */
216 /* Non-zero if this should survive a call to free_temp_slots. */
218 /* The offset of the slot from the frame_pointer, including extra space
219 for alignment. This info is for combine_temp_slots. */
220 HOST_WIDE_INT base_offset
;
221 /* The size of the slot, including extra space for alignment. This
222 info is for combine_temp_slots. */
223 HOST_WIDE_INT full_size
;
226 /* This structure is used to record MEMs or pseudos used to replace VAR, any
227 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
228 maintain this list in case two operands of an insn were required to match;
229 in that case we must ensure we use the same replacement. */
231 struct fixup_replacement
235 struct fixup_replacement
*next
;
238 struct insns_for_mem_entry
{
239 /* The KEY in HE will be a MEM. */
240 struct hash_entry he
;
241 /* These are the INSNS which reference the MEM. */
245 /* Forward declarations. */
247 static rtx assign_stack_local_1
PARAMS ((enum machine_mode
, HOST_WIDE_INT
,
248 int, struct function
*));
249 static rtx assign_stack_temp_for_type
PARAMS ((enum machine_mode
,
250 HOST_WIDE_INT
, int, tree
));
251 static struct temp_slot
*find_temp_slot_from_address
PARAMS ((rtx
));
252 static void put_reg_into_stack
PARAMS ((struct function
*, rtx
, tree
,
253 enum machine_mode
, enum machine_mode
,
254 int, unsigned int, int,
255 struct hash_table
*));
256 static void fixup_var_refs
PARAMS ((rtx
, enum machine_mode
, int,
257 struct hash_table
*));
258 static struct fixup_replacement
259 *find_fixup_replacement
PARAMS ((struct fixup_replacement
**, rtx
));
260 static void fixup_var_refs_insns
PARAMS ((rtx
, enum machine_mode
, int,
261 rtx
, int, struct hash_table
*));
262 static void fixup_var_refs_1
PARAMS ((rtx
, enum machine_mode
, rtx
*, rtx
,
263 struct fixup_replacement
**));
264 static rtx fixup_memory_subreg
PARAMS ((rtx
, rtx
, int));
265 static rtx walk_fixup_memory_subreg
PARAMS ((rtx
, rtx
, int));
266 static rtx fixup_stack_1
PARAMS ((rtx
, rtx
));
267 static void optimize_bit_field
PARAMS ((rtx
, rtx
, rtx
*));
268 static void instantiate_decls
PARAMS ((tree
, int));
269 static void instantiate_decls_1
PARAMS ((tree
, int));
270 static void instantiate_decl
PARAMS ((rtx
, HOST_WIDE_INT
, int));
271 static int instantiate_virtual_regs_1
PARAMS ((rtx
*, rtx
, int));
272 static void delete_handlers
PARAMS ((void));
273 static void pad_to_arg_alignment
PARAMS ((struct args_size
*, int,
274 struct args_size
*));
275 #ifndef ARGS_GROW_DOWNWARD
276 static void pad_below
PARAMS ((struct args_size
*, enum machine_mode
,
279 #ifdef ARGS_GROW_DOWNWARD
280 static tree round_down
PARAMS ((tree
, int));
282 static rtx round_trampoline_addr
PARAMS ((rtx
));
283 static tree
*identify_blocks_1
PARAMS ((rtx
, tree
*, tree
*, tree
*));
284 static void reorder_blocks_1
PARAMS ((rtx
, tree
, varray_type
*));
285 static tree blocks_nreverse
PARAMS ((tree
));
286 static int all_blocks
PARAMS ((tree
, tree
*));
287 static tree
*get_block_vector
PARAMS ((tree
, int *));
288 /* We always define `record_insns' even if its not used so that we
289 can always export `prologue_epilogue_contains'. */
290 static void record_insns
PARAMS ((rtx
, varray_type
*)) ATTRIBUTE_UNUSED
;
291 static int contains
PARAMS ((rtx
, varray_type
));
293 static void emit_return_into_block
PARAMS ((basic_block
));
295 static void put_addressof_into_stack
PARAMS ((rtx
, struct hash_table
*));
296 static boolean purge_addressof_1
PARAMS ((rtx
*, rtx
, int, int,
297 struct hash_table
*));
298 static int is_addressof
PARAMS ((rtx
*, void *));
299 static struct hash_entry
*insns_for_mem_newfunc
PARAMS ((struct hash_entry
*,
302 static unsigned long insns_for_mem_hash
PARAMS ((hash_table_key
));
303 static boolean insns_for_mem_comp
PARAMS ((hash_table_key
, hash_table_key
));
304 static int insns_for_mem_walk
PARAMS ((rtx
*, void *));
305 static void compute_insns_for_mem
PARAMS ((rtx
, rtx
, struct hash_table
*));
306 static void mark_temp_slot
PARAMS ((struct temp_slot
*));
307 static void mark_function_status
PARAMS ((struct function
*));
308 static void mark_function_chain
PARAMS ((void *));
309 static void prepare_function_start
PARAMS ((void));
310 static void do_clobber_return_reg
PARAMS ((rtx
, void *));
311 static void do_use_return_reg
PARAMS ((rtx
, void *));
313 /* Pointer to chain of `struct function' for containing functions. */
314 struct function
*outer_function_chain
;
316 /* Given a function decl for a containing function,
317 return the `struct function' for it. */
320 find_function_data (decl
)
325 for (p
= outer_function_chain
; p
; p
= p
->next
)
332 /* Save the current context for compilation of a nested function.
333 This is called from language-specific code. The caller should use
334 the save_lang_status callback to save any language-specific state,
335 since this function knows only about language-independent
339 push_function_context_to (context
)
342 struct function
*p
, *context_data
;
346 context_data
= (context
== current_function_decl
348 : find_function_data (context
));
349 context_data
->contains_functions
= 1;
353 init_dummy_function_start ();
356 p
->next
= outer_function_chain
;
357 outer_function_chain
= p
;
358 p
->fixup_var_refs_queue
= 0;
360 save_tree_status (p
);
361 if (save_lang_status
)
362 (*save_lang_status
) (p
);
363 if (save_machine_status
)
364 (*save_machine_status
) (p
);
370 push_function_context ()
372 push_function_context_to (current_function_decl
);
375 /* Restore the last saved context, at the end of a nested function.
376 This function is called from language-specific code. */
379 pop_function_context_from (context
)
380 tree context ATTRIBUTE_UNUSED
;
382 struct function
*p
= outer_function_chain
;
383 struct var_refs_queue
*queue
;
384 struct var_refs_queue
*next
;
387 outer_function_chain
= p
->next
;
389 current_function_decl
= p
->decl
;
392 restore_tree_status (p
);
393 restore_emit_status (p
);
395 if (restore_machine_status
)
396 (*restore_machine_status
) (p
);
397 if (restore_lang_status
)
398 (*restore_lang_status
) (p
);
400 /* Finish doing put_var_into_stack for any of our variables
401 which became addressable during the nested function. */
402 for (queue
= p
->fixup_var_refs_queue
; queue
; queue
= next
)
405 fixup_var_refs (queue
->modified
, queue
->promoted_mode
,
406 queue
->unsignedp
, 0);
409 p
->fixup_var_refs_queue
= 0;
411 /* Reset variables that have known state during rtx generation. */
412 rtx_equal_function_value_matters
= 1;
413 virtuals_instantiated
= 0;
417 pop_function_context ()
419 pop_function_context_from (current_function_decl
);
422 /* Clear out all parts of the state in F that can safely be discarded
423 after the function has been parsed, but not compiled, to let
424 garbage collection reclaim the memory. */
427 free_after_parsing (f
)
430 /* f->expr->forced_labels is used by code generation. */
431 /* f->emit->regno_reg_rtx is used by code generation. */
432 /* f->varasm is used by code generation. */
433 /* f->eh->eh_return_stub_label is used by code generation. */
435 if (free_lang_status
)
436 (*free_lang_status
) (f
);
437 free_stmt_status (f
);
440 /* Clear out all parts of the state in F that can safely be discarded
441 after the function has been compiled, to let garbage collection
442 reclaim the memory. */
445 free_after_compilation (f
)
448 struct temp_slot
*ts
;
449 struct temp_slot
*next
;
452 free_expr_status (f
);
453 free_emit_status (f
);
454 free_varasm_status (f
);
456 if (free_machine_status
)
457 (*free_machine_status
) (f
);
459 if (f
->x_parm_reg_stack_loc
)
460 free (f
->x_parm_reg_stack_loc
);
462 for (ts
= f
->x_temp_slots
; ts
; ts
= next
)
467 f
->x_temp_slots
= NULL
;
469 f
->arg_offset_rtx
= NULL
;
470 f
->return_rtx
= NULL
;
471 f
->internal_arg_pointer
= NULL
;
472 f
->x_nonlocal_labels
= NULL
;
473 f
->x_nonlocal_goto_handler_slots
= NULL
;
474 f
->x_nonlocal_goto_handler_labels
= NULL
;
475 f
->x_nonlocal_goto_stack_level
= NULL
;
476 f
->x_cleanup_label
= NULL
;
477 f
->x_return_label
= NULL
;
478 f
->x_save_expr_regs
= NULL
;
479 f
->x_stack_slot_list
= NULL
;
480 f
->x_rtl_expr_chain
= NULL
;
481 f
->x_tail_recursion_label
= NULL
;
482 f
->x_tail_recursion_reentry
= NULL
;
483 f
->x_arg_pointer_save_area
= NULL
;
484 f
->x_context_display
= NULL
;
485 f
->x_trampoline_list
= NULL
;
486 f
->x_parm_birth_insn
= NULL
;
487 f
->x_last_parm_insn
= NULL
;
488 f
->x_parm_reg_stack_loc
= NULL
;
489 f
->fixup_var_refs_queue
= NULL
;
490 f
->original_arg_vector
= NULL
;
491 f
->original_decl_initial
= NULL
;
492 f
->inl_last_parm_insn
= NULL
;
493 f
->epilogue_delay_list
= NULL
;
497 /* Allocate fixed slots in the stack frame of the current function. */
499 /* Return size needed for stack frame based on slots so far allocated in
501 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
502 the caller may have to do that. */
505 get_func_frame_size (f
)
508 #ifdef FRAME_GROWS_DOWNWARD
509 return -f
->x_frame_offset
;
511 return f
->x_frame_offset
;
515 /* Return size needed for stack frame based on slots so far allocated.
516 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
517 the caller may have to do that. */
521 return get_func_frame_size (cfun
);
524 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
525 with machine mode MODE.
527 ALIGN controls the amount of alignment for the address of the slot:
528 0 means according to MODE,
529 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
530 positive specifies alignment boundary in bits.
532 We do not round to stack_boundary here.
534 FUNCTION specifies the function to allocate in. */
537 assign_stack_local_1 (mode
, size
, align
, function
)
538 enum machine_mode mode
;
541 struct function
*function
;
543 register rtx x
, addr
;
544 int bigend_correction
= 0;
547 /* Allocate in the memory associated with the function in whose frame
549 if (function
!= cfun
)
550 push_obstacks (function
->function_obstack
,
551 function
->function_maybepermanent_obstack
);
557 alignment
= GET_MODE_ALIGNMENT (mode
);
559 alignment
= BIGGEST_ALIGNMENT
;
561 /* Allow the target to (possibly) increase the alignment of this
563 type
= type_for_mode (mode
, 0);
565 alignment
= LOCAL_ALIGNMENT (type
, alignment
);
567 alignment
/= BITS_PER_UNIT
;
569 else if (align
== -1)
571 alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
572 size
= CEIL_ROUND (size
, alignment
);
575 alignment
= align
/ BITS_PER_UNIT
;
577 #ifdef FRAME_GROWS_DOWNWARD
578 function
->x_frame_offset
-= size
;
581 /* Ignore alignment we can't do with expected alignment of the boundary. */
582 if (alignment
* BITS_PER_UNIT
> PREFERRED_STACK_BOUNDARY
)
583 alignment
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
585 if (function
->stack_alignment_needed
< alignment
* BITS_PER_UNIT
)
586 function
->stack_alignment_needed
= alignment
* BITS_PER_UNIT
;
588 /* Round frame offset to that alignment.
589 We must be careful here, since FRAME_OFFSET might be negative and
590 division with a negative dividend isn't as well defined as we might
591 like. So we instead assume that ALIGNMENT is a power of two and
592 use logical operations which are unambiguous. */
593 #ifdef FRAME_GROWS_DOWNWARD
594 function
->x_frame_offset
= FLOOR_ROUND (function
->x_frame_offset
, alignment
);
596 function
->x_frame_offset
= CEIL_ROUND (function
->x_frame_offset
, alignment
);
599 /* On a big-endian machine, if we are allocating more space than we will use,
600 use the least significant bytes of those that are allocated. */
601 if (BYTES_BIG_ENDIAN
&& mode
!= BLKmode
)
602 bigend_correction
= size
- GET_MODE_SIZE (mode
);
604 /* If we have already instantiated virtual registers, return the actual
605 address relative to the frame pointer. */
606 if (function
== cfun
&& virtuals_instantiated
)
607 addr
= plus_constant (frame_pointer_rtx
,
608 (frame_offset
+ bigend_correction
609 + STARTING_FRAME_OFFSET
));
611 addr
= plus_constant (virtual_stack_vars_rtx
,
612 function
->x_frame_offset
+ bigend_correction
);
614 #ifndef FRAME_GROWS_DOWNWARD
615 function
->x_frame_offset
+= size
;
618 x
= gen_rtx_MEM (mode
, addr
);
620 function
->x_stack_slot_list
621 = gen_rtx_EXPR_LIST (VOIDmode
, x
, function
->x_stack_slot_list
);
623 if (function
!= cfun
)
629 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
632 assign_stack_local (mode
, size
, align
)
633 enum machine_mode mode
;
637 return assign_stack_local_1 (mode
, size
, align
, cfun
);
640 /* Allocate a temporary stack slot and record it for possible later
643 MODE is the machine mode to be given to the returned rtx.
645 SIZE is the size in units of the space required. We do no rounding here
646 since assign_stack_local will do any required rounding.
648 KEEP is 1 if this slot is to be retained after a call to
649 free_temp_slots. Automatic variables for a block are allocated
650 with this flag. KEEP is 2 if we allocate a longer term temporary,
651 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
652 if we are to allocate something at an inner level to be treated as
653 a variable in the block (e.g., a SAVE_EXPR).
655 TYPE is the type that will be used for the stack slot. */
658 assign_stack_temp_for_type (mode
, size
, keep
, type
)
659 enum machine_mode mode
;
666 struct temp_slot
*p
, *best_p
= 0;
668 /* If SIZE is -1 it means that somebody tried to allocate a temporary
669 of a variable size. */
673 /* If we know the alias set for the memory that will be used, use
674 it. If there's no TYPE, then we don't know anything about the
675 alias set for the memory. */
677 alias_set
= get_alias_set (type
);
681 align
= GET_MODE_ALIGNMENT (mode
);
683 align
= BIGGEST_ALIGNMENT
;
686 type
= type_for_mode (mode
, 0);
688 align
= LOCAL_ALIGNMENT (type
, align
);
690 /* Try to find an available, already-allocated temporary of the proper
691 mode which meets the size and alignment requirements. Choose the
692 smallest one with the closest alignment. */
693 for (p
= temp_slots
; p
; p
= p
->next
)
694 if (p
->align
>= align
&& p
->size
>= size
&& GET_MODE (p
->slot
) == mode
696 && (!flag_strict_aliasing
697 || (alias_set
&& p
->alias_set
== alias_set
))
698 && (best_p
== 0 || best_p
->size
> p
->size
699 || (best_p
->size
== p
->size
&& best_p
->align
> p
->align
)))
701 if (p
->align
== align
&& p
->size
== size
)
709 /* Make our best, if any, the one to use. */
712 /* If there are enough aligned bytes left over, make them into a new
713 temp_slot so that the extra bytes don't get wasted. Do this only
714 for BLKmode slots, so that we can be sure of the alignment. */
715 if (GET_MODE (best_p
->slot
) == BLKmode
716 /* We can't split slots if -fstrict-aliasing because the
717 information about the alias set for the new slot will be
719 && !flag_strict_aliasing
)
721 int alignment
= best_p
->align
/ BITS_PER_UNIT
;
722 HOST_WIDE_INT rounded_size
= CEIL_ROUND (size
, alignment
);
724 if (best_p
->size
- rounded_size
>= alignment
)
726 p
= (struct temp_slot
*) xmalloc (sizeof (struct temp_slot
));
727 p
->in_use
= p
->addr_taken
= 0;
728 p
->size
= best_p
->size
- rounded_size
;
729 p
->base_offset
= best_p
->base_offset
+ rounded_size
;
730 p
->full_size
= best_p
->full_size
- rounded_size
;
731 p
->slot
= gen_rtx_MEM (BLKmode
,
732 plus_constant (XEXP (best_p
->slot
, 0),
734 p
->align
= best_p
->align
;
737 p
->next
= temp_slots
;
740 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, p
->slot
,
743 best_p
->size
= rounded_size
;
744 best_p
->full_size
= rounded_size
;
751 /* If we still didn't find one, make a new temporary. */
754 HOST_WIDE_INT frame_offset_old
= frame_offset
;
756 p
= (struct temp_slot
*) xmalloc (sizeof (struct temp_slot
));
758 /* We are passing an explicit alignment request to assign_stack_local.
759 One side effect of that is assign_stack_local will not round SIZE
760 to ensure the frame offset remains suitably aligned.
762 So for requests which depended on the rounding of SIZE, we go ahead
763 and round it now. We also make sure ALIGNMENT is at least
764 BIGGEST_ALIGNMENT. */
765 if (mode
== BLKmode
&& align
< BIGGEST_ALIGNMENT
)
767 p
->slot
= assign_stack_local (mode
,
769 ? CEIL_ROUND (size
, align
/ BITS_PER_UNIT
)
774 p
->alias_set
= alias_set
;
776 /* The following slot size computation is necessary because we don't
777 know the actual size of the temporary slot until assign_stack_local
778 has performed all the frame alignment and size rounding for the
779 requested temporary. Note that extra space added for alignment
780 can be either above or below this stack slot depending on which
781 way the frame grows. We include the extra space if and only if it
782 is above this slot. */
783 #ifdef FRAME_GROWS_DOWNWARD
784 p
->size
= frame_offset_old
- frame_offset
;
789 /* Now define the fields used by combine_temp_slots. */
790 #ifdef FRAME_GROWS_DOWNWARD
791 p
->base_offset
= frame_offset
;
792 p
->full_size
= frame_offset_old
- frame_offset
;
794 p
->base_offset
= frame_offset_old
;
795 p
->full_size
= frame_offset
- frame_offset_old
;
798 p
->next
= temp_slots
;
804 p
->rtl_expr
= seq_rtl_expr
;
808 p
->level
= target_temp_slot_level
;
813 p
->level
= var_temp_slot_level
;
818 p
->level
= temp_slot_level
;
822 /* We may be reusing an old slot, so clear any MEM flags that may have been
824 RTX_UNCHANGING_P (p
->slot
) = 0;
825 MEM_IN_STRUCT_P (p
->slot
) = 0;
826 MEM_SCALAR_P (p
->slot
) = 0;
827 MEM_ALIAS_SET (p
->slot
) = 0;
831 /* Allocate a temporary stack slot and record it for possible later
832 reuse. First three arguments are same as in preceding function. */
835 assign_stack_temp (mode
, size
, keep
)
836 enum machine_mode mode
;
840 return assign_stack_temp_for_type (mode
, size
, keep
, NULL_TREE
);
843 /* Assign a temporary of given TYPE.
844 KEEP is as for assign_stack_temp.
845 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
846 it is 0 if a register is OK.
847 DONT_PROMOTE is 1 if we should not promote values in register
851 assign_temp (type
, keep
, memory_required
, dont_promote
)
855 int dont_promote ATTRIBUTE_UNUSED
;
857 enum machine_mode mode
= TYPE_MODE (type
);
858 #ifndef PROMOTE_FOR_CALL_ONLY
859 int unsignedp
= TREE_UNSIGNED (type
);
862 if (mode
== BLKmode
|| memory_required
)
864 HOST_WIDE_INT size
= int_size_in_bytes (type
);
867 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
868 problems with allocating the stack space. */
872 /* Unfortunately, we don't yet know how to allocate variable-sized
873 temporaries. However, sometimes we have a fixed upper limit on
874 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
875 instead. This is the case for Chill variable-sized strings. */
876 if (size
== -1 && TREE_CODE (type
) == ARRAY_TYPE
877 && TYPE_ARRAY_MAX_SIZE (type
) != NULL_TREE
878 && TREE_CODE (TYPE_ARRAY_MAX_SIZE (type
)) == INTEGER_CST
)
879 size
= TREE_INT_CST_LOW (TYPE_ARRAY_MAX_SIZE (type
));
881 tmp
= assign_stack_temp_for_type (mode
, size
, keep
, type
);
882 MEM_SET_IN_STRUCT_P (tmp
, AGGREGATE_TYPE_P (type
));
886 #ifndef PROMOTE_FOR_CALL_ONLY
888 mode
= promote_mode (type
, mode
, &unsignedp
, 0);
891 return gen_reg_rtx (mode
);
894 /* Combine temporary stack slots which are adjacent on the stack.
896 This allows for better use of already allocated stack space. This is only
897 done for BLKmode slots because we can be sure that we won't have alignment
898 problems in this case. */
901 combine_temp_slots ()
903 struct temp_slot
*p
, *q
;
904 struct temp_slot
*prev_p
, *prev_q
;
907 /* We can't combine slots, because the information about which slot
908 is in which alias set will be lost. */
909 if (flag_strict_aliasing
)
912 /* If there are a lot of temp slots, don't do anything unless
913 high levels of optimizaton. */
914 if (! flag_expensive_optimizations
)
915 for (p
= temp_slots
, num_slots
= 0; p
; p
= p
->next
, num_slots
++)
916 if (num_slots
> 100 || (num_slots
> 10 && optimize
== 0))
919 for (p
= temp_slots
, prev_p
= 0; p
; p
= prev_p
? prev_p
->next
: temp_slots
)
923 if (! p
->in_use
&& GET_MODE (p
->slot
) == BLKmode
)
924 for (q
= p
->next
, prev_q
= p
; q
; q
= prev_q
->next
)
927 if (! q
->in_use
&& GET_MODE (q
->slot
) == BLKmode
)
929 if (p
->base_offset
+ p
->full_size
== q
->base_offset
)
931 /* Q comes after P; combine Q into P. */
933 p
->full_size
+= q
->full_size
;
936 else if (q
->base_offset
+ q
->full_size
== p
->base_offset
)
938 /* P comes after Q; combine P into Q. */
940 q
->full_size
+= p
->full_size
;
945 /* Either delete Q or advance past it. */
948 prev_q
->next
= q
->next
;
954 /* Either delete P or advance past it. */
958 prev_p
->next
= p
->next
;
960 temp_slots
= p
->next
;
967 /* Find the temp slot corresponding to the object at address X. */
969 static struct temp_slot
*
970 find_temp_slot_from_address (x
)
976 for (p
= temp_slots
; p
; p
= p
->next
)
981 else if (XEXP (p
->slot
, 0) == x
983 || (GET_CODE (x
) == PLUS
984 && XEXP (x
, 0) == virtual_stack_vars_rtx
985 && GET_CODE (XEXP (x
, 1)) == CONST_INT
986 && INTVAL (XEXP (x
, 1)) >= p
->base_offset
987 && INTVAL (XEXP (x
, 1)) < p
->base_offset
+ p
->full_size
))
990 else if (p
->address
!= 0 && GET_CODE (p
->address
) == EXPR_LIST
)
991 for (next
= p
->address
; next
; next
= XEXP (next
, 1))
992 if (XEXP (next
, 0) == x
)
996 /* If we have a sum involving a register, see if it points to a temp
998 if (GET_CODE (x
) == PLUS
&& GET_CODE (XEXP (x
, 0)) == REG
999 && (p
= find_temp_slot_from_address (XEXP (x
, 0))) != 0)
1001 else if (GET_CODE (x
) == PLUS
&& GET_CODE (XEXP (x
, 1)) == REG
1002 && (p
= find_temp_slot_from_address (XEXP (x
, 1))) != 0)
1008 /* Indicate that NEW is an alternate way of referring to the temp slot
1009 that previously was known by OLD. */
1012 update_temp_slot_address (old
, new)
1015 struct temp_slot
*p
;
1017 if (rtx_equal_p (old
, new))
1020 p
= find_temp_slot_from_address (old
);
1022 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
1023 is a register, see if one operand of the PLUS is a temporary
1024 location. If so, NEW points into it. Otherwise, if both OLD and
1025 NEW are a PLUS and if there is a register in common between them.
1026 If so, try a recursive call on those values. */
1029 if (GET_CODE (old
) != PLUS
)
1032 if (GET_CODE (new) == REG
)
1034 update_temp_slot_address (XEXP (old
, 0), new);
1035 update_temp_slot_address (XEXP (old
, 1), new);
1038 else if (GET_CODE (new) != PLUS
)
1041 if (rtx_equal_p (XEXP (old
, 0), XEXP (new, 0)))
1042 update_temp_slot_address (XEXP (old
, 1), XEXP (new, 1));
1043 else if (rtx_equal_p (XEXP (old
, 1), XEXP (new, 0)))
1044 update_temp_slot_address (XEXP (old
, 0), XEXP (new, 1));
1045 else if (rtx_equal_p (XEXP (old
, 0), XEXP (new, 1)))
1046 update_temp_slot_address (XEXP (old
, 1), XEXP (new, 0));
1047 else if (rtx_equal_p (XEXP (old
, 1), XEXP (new, 1)))
1048 update_temp_slot_address (XEXP (old
, 0), XEXP (new, 0));
1053 /* Otherwise add an alias for the temp's address. */
1054 else if (p
->address
== 0)
1058 if (GET_CODE (p
->address
) != EXPR_LIST
)
1059 p
->address
= gen_rtx_EXPR_LIST (VOIDmode
, p
->address
, NULL_RTX
);
1061 p
->address
= gen_rtx_EXPR_LIST (VOIDmode
, new, p
->address
);
1065 /* If X could be a reference to a temporary slot, mark the fact that its
1066 address was taken. */
1069 mark_temp_addr_taken (x
)
1072 struct temp_slot
*p
;
1077 /* If X is not in memory or is at a constant address, it cannot be in
1078 a temporary slot. */
1079 if (GET_CODE (x
) != MEM
|| CONSTANT_P (XEXP (x
, 0)))
1082 p
= find_temp_slot_from_address (XEXP (x
, 0));
1087 /* If X could be a reference to a temporary slot, mark that slot as
1088 belonging to the to one level higher than the current level. If X
1089 matched one of our slots, just mark that one. Otherwise, we can't
1090 easily predict which it is, so upgrade all of them. Kept slots
1091 need not be touched.
1093 This is called when an ({...}) construct occurs and a statement
1094 returns a value in memory. */
1097 preserve_temp_slots (x
)
1100 struct temp_slot
*p
= 0;
1102 /* If there is no result, we still might have some objects whose address
1103 were taken, so we need to make sure they stay around. */
1106 for (p
= temp_slots
; p
; p
= p
->next
)
1107 if (p
->in_use
&& p
->level
== temp_slot_level
&& p
->addr_taken
)
1113 /* If X is a register that is being used as a pointer, see if we have
1114 a temporary slot we know it points to. To be consistent with
1115 the code below, we really should preserve all non-kept slots
1116 if we can't find a match, but that seems to be much too costly. */
1117 if (GET_CODE (x
) == REG
&& REGNO_POINTER_FLAG (REGNO (x
)))
1118 p
= find_temp_slot_from_address (x
);
1120 /* If X is not in memory or is at a constant address, it cannot be in
1121 a temporary slot, but it can contain something whose address was
1123 if (p
== 0 && (GET_CODE (x
) != MEM
|| CONSTANT_P (XEXP (x
, 0))))
1125 for (p
= temp_slots
; p
; p
= p
->next
)
1126 if (p
->in_use
&& p
->level
== temp_slot_level
&& p
->addr_taken
)
1132 /* First see if we can find a match. */
1134 p
= find_temp_slot_from_address (XEXP (x
, 0));
1138 /* Move everything at our level whose address was taken to our new
1139 level in case we used its address. */
1140 struct temp_slot
*q
;
1142 if (p
->level
== temp_slot_level
)
1144 for (q
= temp_slots
; q
; q
= q
->next
)
1145 if (q
!= p
&& q
->addr_taken
&& q
->level
== p
->level
)
1154 /* Otherwise, preserve all non-kept slots at this level. */
1155 for (p
= temp_slots
; p
; p
= p
->next
)
1156 if (p
->in_use
&& p
->level
== temp_slot_level
&& ! p
->keep
)
1160 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1161 with that RTL_EXPR, promote it into a temporary slot at the present
1162 level so it will not be freed when we free slots made in the
1166 preserve_rtl_expr_result (x
)
1169 struct temp_slot
*p
;
1171 /* If X is not in memory or is at a constant address, it cannot be in
1172 a temporary slot. */
1173 if (x
== 0 || GET_CODE (x
) != MEM
|| CONSTANT_P (XEXP (x
, 0)))
1176 /* If we can find a match, move it to our level unless it is already at
1178 p
= find_temp_slot_from_address (XEXP (x
, 0));
1181 p
->level
= MIN (p
->level
, temp_slot_level
);
1188 /* Free all temporaries used so far. This is normally called at the end
1189 of generating code for a statement. Don't free any temporaries
1190 currently in use for an RTL_EXPR that hasn't yet been emitted.
1191 We could eventually do better than this since it can be reused while
1192 generating the same RTL_EXPR, but this is complex and probably not
1198 struct temp_slot
*p
;
1200 for (p
= temp_slots
; p
; p
= p
->next
)
1201 if (p
->in_use
&& p
->level
== temp_slot_level
&& ! p
->keep
1202 && p
->rtl_expr
== 0)
1205 combine_temp_slots ();
1208 /* Free all temporary slots used in T, an RTL_EXPR node. */
1211 free_temps_for_rtl_expr (t
)
1214 struct temp_slot
*p
;
1216 for (p
= temp_slots
; p
; p
= p
->next
)
1217 if (p
->rtl_expr
== t
)
1219 /* If this slot is below the current TEMP_SLOT_LEVEL, then it
1220 needs to be preserved. This can happen if a temporary in
1221 the RTL_EXPR was addressed; preserve_temp_slots will move
1222 the temporary into a higher level. */
1223 if (temp_slot_level
<= p
->level
)
1226 p
->rtl_expr
= NULL_TREE
;
1229 combine_temp_slots ();
1232 /* Mark all temporaries ever allocated in this function as not suitable
1233 for reuse until the current level is exited. */
1236 mark_all_temps_used ()
1238 struct temp_slot
*p
;
1240 for (p
= temp_slots
; p
; p
= p
->next
)
1242 p
->in_use
= p
->keep
= 1;
1243 p
->level
= MIN (p
->level
, temp_slot_level
);
1247 /* Push deeper into the nesting level for stack temporaries. */
1255 /* Likewise, but save the new level as the place to allocate variables
1260 push_temp_slots_for_block ()
1264 var_temp_slot_level
= temp_slot_level
;
1267 /* Likewise, but save the new level as the place to allocate temporaries
1268 for TARGET_EXPRs. */
1271 push_temp_slots_for_target ()
1275 target_temp_slot_level
= temp_slot_level
;
1278 /* Set and get the value of target_temp_slot_level. The only
1279 permitted use of these functions is to save and restore this value. */
1282 get_target_temp_slot_level ()
1284 return target_temp_slot_level
;
1288 set_target_temp_slot_level (level
)
1291 target_temp_slot_level
= level
;
1295 /* Pop a temporary nesting level. All slots in use in the current level
1301 struct temp_slot
*p
;
1303 for (p
= temp_slots
; p
; p
= p
->next
)
1304 if (p
->in_use
&& p
->level
== temp_slot_level
&& p
->rtl_expr
== 0)
1307 combine_temp_slots ();
1312 /* Initialize temporary slots. */
1317 /* We have not allocated any temporaries yet. */
1319 temp_slot_level
= 0;
1320 var_temp_slot_level
= 0;
1321 target_temp_slot_level
= 0;
1324 /* Retroactively move an auto variable from a register to a stack slot.
1325 This is done when an address-reference to the variable is seen. */
1328 put_var_into_stack (decl
)
1332 enum machine_mode promoted_mode
, decl_mode
;
1333 struct function
*function
= 0;
1335 int can_use_addressof
;
1337 context
= decl_function_context (decl
);
1339 /* Get the current rtl used for this object and its original mode. */
1340 reg
= TREE_CODE (decl
) == SAVE_EXPR
? SAVE_EXPR_RTL (decl
) : DECL_RTL (decl
);
1342 /* No need to do anything if decl has no rtx yet
1343 since in that case caller is setting TREE_ADDRESSABLE
1344 and a stack slot will be assigned when the rtl is made. */
1348 /* Get the declared mode for this object. */
1349 decl_mode
= (TREE_CODE (decl
) == SAVE_EXPR
? TYPE_MODE (TREE_TYPE (decl
))
1350 : DECL_MODE (decl
));
1351 /* Get the mode it's actually stored in. */
1352 promoted_mode
= GET_MODE (reg
);
1354 /* If this variable comes from an outer function,
1355 find that function's saved context. */
1356 if (context
!= current_function_decl
&& context
!= inline_function_decl
)
1357 for (function
= outer_function_chain
; function
; function
= function
->next
)
1358 if (function
->decl
== context
)
1361 /* If this is a variable-size object with a pseudo to address it,
1362 put that pseudo into the stack, if the var is nonlocal. */
1363 if (DECL_NONLOCAL (decl
)
1364 && GET_CODE (reg
) == MEM
1365 && GET_CODE (XEXP (reg
, 0)) == REG
1366 && REGNO (XEXP (reg
, 0)) > LAST_VIRTUAL_REGISTER
)
1368 reg
= XEXP (reg
, 0);
1369 decl_mode
= promoted_mode
= GET_MODE (reg
);
1375 /* FIXME make it work for promoted modes too */
1376 && decl_mode
== promoted_mode
1377 #ifdef NON_SAVING_SETJMP
1378 && ! (NON_SAVING_SETJMP
&& current_function_calls_setjmp
)
1382 /* If we can't use ADDRESSOF, make sure we see through one we already
1384 if (! can_use_addressof
&& GET_CODE (reg
) == MEM
1385 && GET_CODE (XEXP (reg
, 0)) == ADDRESSOF
)
1386 reg
= XEXP (XEXP (reg
, 0), 0);
1388 /* Now we should have a value that resides in one or more pseudo regs. */
1390 if (GET_CODE (reg
) == REG
)
1392 /* If this variable lives in the current function and we don't need
1393 to put things in the stack for the sake of setjmp, try to keep it
1394 in a register until we know we actually need the address. */
1395 if (can_use_addressof
)
1396 gen_mem_addressof (reg
, decl
);
1398 put_reg_into_stack (function
, reg
, TREE_TYPE (decl
),
1399 promoted_mode
, decl_mode
,
1400 TREE_SIDE_EFFECTS (decl
), 0,
1401 TREE_USED (decl
) || DECL_INITIAL (decl
) != 0,
1404 else if (GET_CODE (reg
) == CONCAT
)
1406 /* A CONCAT contains two pseudos; put them both in the stack.
1407 We do it so they end up consecutive. */
1408 enum machine_mode part_mode
= GET_MODE (XEXP (reg
, 0));
1409 tree part_type
= type_for_mode (part_mode
, 0);
1410 #ifdef FRAME_GROWS_DOWNWARD
1411 /* Since part 0 should have a lower address, do it second. */
1412 put_reg_into_stack (function
, XEXP (reg
, 1), part_type
, part_mode
,
1413 part_mode
, TREE_SIDE_EFFECTS (decl
), 0,
1414 TREE_USED (decl
) || DECL_INITIAL (decl
) != 0,
1416 put_reg_into_stack (function
, XEXP (reg
, 0), part_type
, part_mode
,
1417 part_mode
, TREE_SIDE_EFFECTS (decl
), 0,
1418 TREE_USED (decl
) || DECL_INITIAL (decl
) != 0,
1421 put_reg_into_stack (function
, XEXP (reg
, 0), part_type
, part_mode
,
1422 part_mode
, TREE_SIDE_EFFECTS (decl
), 0,
1423 TREE_USED (decl
) || DECL_INITIAL (decl
) != 0,
1425 put_reg_into_stack (function
, XEXP (reg
, 1), part_type
, part_mode
,
1426 part_mode
, TREE_SIDE_EFFECTS (decl
), 0,
1427 TREE_USED (decl
) || DECL_INITIAL (decl
) != 0,
1431 /* Change the CONCAT into a combined MEM for both parts. */
1432 PUT_CODE (reg
, MEM
);
1433 MEM_VOLATILE_P (reg
) = MEM_VOLATILE_P (XEXP (reg
, 0));
1434 MEM_ALIAS_SET (reg
) = get_alias_set (decl
);
1435 MEM_SET_IN_STRUCT_P (reg
, AGGREGATE_TYPE_P (TREE_TYPE (decl
)));
1437 /* The two parts are in memory order already.
1438 Use the lower parts address as ours. */
1439 XEXP (reg
, 0) = XEXP (XEXP (reg
, 0), 0);
1440 /* Prevent sharing of rtl that might lose. */
1441 if (GET_CODE (XEXP (reg
, 0)) == PLUS
)
1442 XEXP (reg
, 0) = copy_rtx (XEXP (reg
, 0));
1447 if (current_function_check_memory_usage
)
1448 emit_library_call (chkr_set_right_libfunc
, 1, VOIDmode
, 3,
1449 XEXP (reg
, 0), Pmode
,
1450 GEN_INT (GET_MODE_SIZE (GET_MODE (reg
))),
1451 TYPE_MODE (sizetype
),
1452 GEN_INT (MEMORY_USE_RW
),
1453 TYPE_MODE (integer_type_node
));
1456 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1457 into the stack frame of FUNCTION (0 means the current function).
1458 DECL_MODE is the machine mode of the user-level data type.
1459 PROMOTED_MODE is the machine mode of the register.
1460 VOLATILE_P is nonzero if this is for a "volatile" decl.
1461 USED_P is nonzero if this reg might have already been used in an insn. */
1464 put_reg_into_stack (function
, reg
, type
, promoted_mode
, decl_mode
, volatile_p
,
1465 original_regno
, used_p
, ht
)
1466 struct function
*function
;
1469 enum machine_mode promoted_mode
, decl_mode
;
1471 unsigned int original_regno
;
1473 struct hash_table
*ht
;
1475 struct function
*func
= function
? function
: cfun
;
1477 unsigned int regno
= original_regno
;
1480 regno
= REGNO (reg
);
1482 if (regno
< func
->x_max_parm_reg
)
1483 new = func
->x_parm_reg_stack_loc
[regno
];
1486 new = assign_stack_local_1 (decl_mode
, GET_MODE_SIZE (decl_mode
), 0, func
);
1488 PUT_CODE (reg
, MEM
);
1489 PUT_MODE (reg
, decl_mode
);
1490 XEXP (reg
, 0) = XEXP (new, 0);
1491 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1492 MEM_VOLATILE_P (reg
) = volatile_p
;
1494 /* If this is a memory ref that contains aggregate components,
1495 mark it as such for cse and loop optimize. If we are reusing a
1496 previously generated stack slot, then we need to copy the bit in
1497 case it was set for other reasons. For instance, it is set for
1498 __builtin_va_alist. */
1499 MEM_SET_IN_STRUCT_P (reg
,
1500 AGGREGATE_TYPE_P (type
) || MEM_IN_STRUCT_P (new));
1501 MEM_ALIAS_SET (reg
) = get_alias_set (type
);
1503 /* Now make sure that all refs to the variable, previously made
1504 when it was a register, are fixed up to be valid again. */
1506 if (used_p
&& function
!= 0)
1508 struct var_refs_queue
*temp
;
1511 = (struct var_refs_queue
*) xmalloc (sizeof (struct var_refs_queue
));
1512 temp
->modified
= reg
;
1513 temp
->promoted_mode
= promoted_mode
;
1514 temp
->unsignedp
= TREE_UNSIGNED (type
);
1515 temp
->next
= function
->fixup_var_refs_queue
;
1516 function
->fixup_var_refs_queue
= temp
;
1519 /* Variable is local; fix it up now. */
1520 fixup_var_refs (reg
, promoted_mode
, TREE_UNSIGNED (type
), ht
);
1524 fixup_var_refs (var
, promoted_mode
, unsignedp
, ht
)
1526 enum machine_mode promoted_mode
;
1528 struct hash_table
*ht
;
1531 rtx first_insn
= get_insns ();
1532 struct sequence_stack
*stack
= seq_stack
;
1533 tree rtl_exps
= rtl_expr_chain
;
1536 /* Must scan all insns for stack-refs that exceed the limit. */
1537 fixup_var_refs_insns (var
, promoted_mode
, unsignedp
, first_insn
,
1539 /* If there's a hash table, it must record all uses of VAR. */
1543 /* Scan all pending sequences too. */
1544 for (; stack
; stack
= stack
->next
)
1546 push_to_sequence (stack
->first
);
1547 fixup_var_refs_insns (var
, promoted_mode
, unsignedp
,
1548 stack
->first
, stack
->next
!= 0, 0);
1549 /* Update remembered end of sequence
1550 in case we added an insn at the end. */
1551 stack
->last
= get_last_insn ();
1555 /* Scan all waiting RTL_EXPRs too. */
1556 for (pending
= rtl_exps
; pending
; pending
= TREE_CHAIN (pending
))
1558 rtx seq
= RTL_EXPR_SEQUENCE (TREE_VALUE (pending
));
1559 if (seq
!= const0_rtx
&& seq
!= 0)
1561 push_to_sequence (seq
);
1562 fixup_var_refs_insns (var
, promoted_mode
, unsignedp
, seq
, 0,
1568 /* Scan the catch clauses for exception handling too. */
1569 push_to_full_sequence (catch_clauses
, catch_clauses_last
);
1570 fixup_var_refs_insns (var
, promoted_mode
, unsignedp
, catch_clauses
,
1572 end_full_sequence (&catch_clauses
, &catch_clauses_last
);
1574 /* Scan sequences saved in CALL_PLACEHOLDERS too. */
1575 for (insn
= first_insn
; insn
; insn
= NEXT_INSN (insn
))
1577 if (GET_CODE (insn
) == CALL_INSN
1578 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
1582 /* Look at the Normal call, sibling call and tail recursion
1583 sequences attached to the CALL_PLACEHOLDER. */
1584 for (i
= 0; i
< 3; i
++)
1586 rtx seq
= XEXP (PATTERN (insn
), i
);
1589 push_to_sequence (seq
);
1590 fixup_var_refs_insns (var
, promoted_mode
, unsignedp
,
1592 XEXP (PATTERN (insn
), i
) = get_insns ();
1600 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1601 some part of an insn. Return a struct fixup_replacement whose OLD
1602 value is equal to X. Allocate a new structure if no such entry exists. */
1604 static struct fixup_replacement
*
1605 find_fixup_replacement (replacements
, x
)
1606 struct fixup_replacement
**replacements
;
1609 struct fixup_replacement
*p
;
1611 /* See if we have already replaced this. */
1612 for (p
= *replacements
; p
!= 0 && ! rtx_equal_p (p
->old
, x
); p
= p
->next
)
1617 p
= (struct fixup_replacement
*) oballoc (sizeof (struct fixup_replacement
));
1620 p
->next
= *replacements
;
1627 /* Scan the insn-chain starting with INSN for refs to VAR
1628 and fix them up. TOPLEVEL is nonzero if this chain is the
1629 main chain of insns for the current function. */
1632 fixup_var_refs_insns (var
, promoted_mode
, unsignedp
, insn
, toplevel
, ht
)
1634 enum machine_mode promoted_mode
;
1638 struct hash_table
*ht
;
1641 rtx insn_list
= NULL_RTX
;
1643 /* If we already know which INSNs reference VAR there's no need
1644 to walk the entire instruction chain. */
1647 insn_list
= ((struct insns_for_mem_entry
*)
1648 hash_lookup (ht
, var
, /*create=*/0, /*copy=*/0))->insns
;
1649 insn
= insn_list
? XEXP (insn_list
, 0) : NULL_RTX
;
1650 insn_list
= XEXP (insn_list
, 1);
1655 rtx next
= NEXT_INSN (insn
);
1656 rtx set
, prev
, prev_set
;
1659 if (GET_RTX_CLASS (GET_CODE (insn
)) == 'i')
1661 /* Remember the notes in case we delete the insn. */
1662 note
= REG_NOTES (insn
);
1664 /* If this is a CLOBBER of VAR, delete it.
1666 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1667 and REG_RETVAL notes too. */
1668 if (GET_CODE (PATTERN (insn
)) == CLOBBER
1669 && (XEXP (PATTERN (insn
), 0) == var
1670 || (GET_CODE (XEXP (PATTERN (insn
), 0)) == CONCAT
1671 && (XEXP (XEXP (PATTERN (insn
), 0), 0) == var
1672 || XEXP (XEXP (PATTERN (insn
), 0), 1) == var
))))
1674 if ((note
= find_reg_note (insn
, REG_LIBCALL
, NULL_RTX
)) != 0)
1675 /* The REG_LIBCALL note will go away since we are going to
1676 turn INSN into a NOTE, so just delete the
1677 corresponding REG_RETVAL note. */
1678 remove_note (XEXP (note
, 0),
1679 find_reg_note (XEXP (note
, 0), REG_RETVAL
,
1682 /* In unoptimized compilation, we shouldn't call delete_insn
1683 except in jump.c doing warnings. */
1684 PUT_CODE (insn
, NOTE
);
1685 NOTE_LINE_NUMBER (insn
) = NOTE_INSN_DELETED
;
1686 NOTE_SOURCE_FILE (insn
) = 0;
1689 /* The insn to load VAR from a home in the arglist
1690 is now a no-op. When we see it, just delete it.
1691 Similarly if this is storing VAR from a register from which
1692 it was loaded in the previous insn. This will occur
1693 when an ADDRESSOF was made for an arglist slot. */
1695 && (set
= single_set (insn
)) != 0
1696 && SET_DEST (set
) == var
1697 /* If this represents the result of an insn group,
1698 don't delete the insn. */
1699 && find_reg_note (insn
, REG_RETVAL
, NULL_RTX
) == 0
1700 && (rtx_equal_p (SET_SRC (set
), var
)
1701 || (GET_CODE (SET_SRC (set
)) == REG
1702 && (prev
= prev_nonnote_insn (insn
)) != 0
1703 && (prev_set
= single_set (prev
)) != 0
1704 && SET_DEST (prev_set
) == SET_SRC (set
)
1705 && rtx_equal_p (SET_SRC (prev_set
), var
))))
1707 /* In unoptimized compilation, we shouldn't call delete_insn
1708 except in jump.c doing warnings. */
1709 PUT_CODE (insn
, NOTE
);
1710 NOTE_LINE_NUMBER (insn
) = NOTE_INSN_DELETED
;
1711 NOTE_SOURCE_FILE (insn
) = 0;
1712 if (insn
== last_parm_insn
)
1713 last_parm_insn
= PREV_INSN (next
);
1717 struct fixup_replacement
*replacements
= 0;
1718 rtx next_insn
= NEXT_INSN (insn
);
1720 if (SMALL_REGISTER_CLASSES
)
1722 /* If the insn that copies the results of a CALL_INSN
1723 into a pseudo now references VAR, we have to use an
1724 intermediate pseudo since we want the life of the
1725 return value register to be only a single insn.
1727 If we don't use an intermediate pseudo, such things as
1728 address computations to make the address of VAR valid
1729 if it is not can be placed between the CALL_INSN and INSN.
1731 To make sure this doesn't happen, we record the destination
1732 of the CALL_INSN and see if the next insn uses both that
1735 if (call_dest
!= 0 && GET_CODE (insn
) == INSN
1736 && reg_mentioned_p (var
, PATTERN (insn
))
1737 && reg_mentioned_p (call_dest
, PATTERN (insn
)))
1739 rtx temp
= gen_reg_rtx (GET_MODE (call_dest
));
1741 emit_insn_before (gen_move_insn (temp
, call_dest
), insn
);
1743 PATTERN (insn
) = replace_rtx (PATTERN (insn
),
1747 if (GET_CODE (insn
) == CALL_INSN
1748 && GET_CODE (PATTERN (insn
)) == SET
)
1749 call_dest
= SET_DEST (PATTERN (insn
));
1750 else if (GET_CODE (insn
) == CALL_INSN
1751 && GET_CODE (PATTERN (insn
)) == PARALLEL
1752 && GET_CODE (XVECEXP (PATTERN (insn
), 0, 0)) == SET
)
1753 call_dest
= SET_DEST (XVECEXP (PATTERN (insn
), 0, 0));
1758 /* See if we have to do anything to INSN now that VAR is in
1759 memory. If it needs to be loaded into a pseudo, use a single
1760 pseudo for the entire insn in case there is a MATCH_DUP
1761 between two operands. We pass a pointer to the head of
1762 a list of struct fixup_replacements. If fixup_var_refs_1
1763 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1764 it will record them in this list.
1766 If it allocated a pseudo for any replacement, we copy into
1769 fixup_var_refs_1 (var
, promoted_mode
, &PATTERN (insn
), insn
,
1772 /* If this is last_parm_insn, and any instructions were output
1773 after it to fix it up, then we must set last_parm_insn to
1774 the last such instruction emitted. */
1775 if (insn
== last_parm_insn
)
1776 last_parm_insn
= PREV_INSN (next_insn
);
1778 while (replacements
)
1780 if (GET_CODE (replacements
->new) == REG
)
1785 /* OLD might be a (subreg (mem)). */
1786 if (GET_CODE (replacements
->old
) == SUBREG
)
1788 = fixup_memory_subreg (replacements
->old
, insn
, 0);
1791 = fixup_stack_1 (replacements
->old
, insn
);
1793 insert_before
= insn
;
1795 /* If we are changing the mode, do a conversion.
1796 This might be wasteful, but combine.c will
1797 eliminate much of the waste. */
1799 if (GET_MODE (replacements
->new)
1800 != GET_MODE (replacements
->old
))
1803 convert_move (replacements
->new,
1804 replacements
->old
, unsignedp
);
1805 seq
= gen_sequence ();
1809 seq
= gen_move_insn (replacements
->new,
1812 emit_insn_before (seq
, insert_before
);
1815 replacements
= replacements
->next
;
1819 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1820 But don't touch other insns referred to by reg-notes;
1821 we will get them elsewhere. */
1824 if (GET_CODE (note
) != INSN_LIST
)
1826 = walk_fixup_memory_subreg (XEXP (note
, 0), insn
, 1);
1827 note
= XEXP (note
, 1);
1835 insn
= XEXP (insn_list
, 0);
1836 insn_list
= XEXP (insn_list
, 1);
1843 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1844 See if the rtx expression at *LOC in INSN needs to be changed.
1846 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1847 contain a list of original rtx's and replacements. If we find that we need
1848 to modify this insn by replacing a memory reference with a pseudo or by
1849 making a new MEM to implement a SUBREG, we consult that list to see if
1850 we have already chosen a replacement. If none has already been allocated,
1851 we allocate it and update the list. fixup_var_refs_insns will copy VAR
1852 or the SUBREG, as appropriate, to the pseudo. */
1855 fixup_var_refs_1 (var
, promoted_mode
, loc
, insn
, replacements
)
1857 enum machine_mode promoted_mode
;
1860 struct fixup_replacement
**replacements
;
1863 register rtx x
= *loc
;
1864 RTX_CODE code
= GET_CODE (x
);
1865 register const char *fmt
;
1866 register rtx tem
, tem1
;
1867 struct fixup_replacement
*replacement
;
1872 if (XEXP (x
, 0) == var
)
1874 /* Prevent sharing of rtl that might lose. */
1875 rtx sub
= copy_rtx (XEXP (var
, 0));
1877 if (! validate_change (insn
, loc
, sub
, 0))
1879 rtx y
= gen_reg_rtx (GET_MODE (sub
));
1882 /* We should be able to replace with a register or all is lost.
1883 Note that we can't use validate_change to verify this, since
1884 we're not caring for replacing all dups simultaneously. */
1885 if (! validate_replace_rtx (*loc
, y
, insn
))
1888 /* Careful! First try to recognize a direct move of the
1889 value, mimicking how things are done in gen_reload wrt
1890 PLUS. Consider what happens when insn is a conditional
1891 move instruction and addsi3 clobbers flags. */
1894 new_insn
= emit_insn (gen_rtx_SET (VOIDmode
, y
, sub
));
1895 seq
= gen_sequence ();
1898 if (recog_memoized (new_insn
) < 0)
1900 /* That failed. Fall back on force_operand and hope. */
1903 force_operand (sub
, y
);
1904 seq
= gen_sequence ();
1909 /* Don't separate setter from user. */
1910 if (PREV_INSN (insn
) && sets_cc0_p (PREV_INSN (insn
)))
1911 insn
= PREV_INSN (insn
);
1914 emit_insn_before (seq
, insn
);
1922 /* If we already have a replacement, use it. Otherwise,
1923 try to fix up this address in case it is invalid. */
1925 replacement
= find_fixup_replacement (replacements
, var
);
1926 if (replacement
->new)
1928 *loc
= replacement
->new;
1932 *loc
= replacement
->new = x
= fixup_stack_1 (x
, insn
);
1934 /* Unless we are forcing memory to register or we changed the mode,
1935 we can leave things the way they are if the insn is valid. */
1937 INSN_CODE (insn
) = -1;
1938 if (! flag_force_mem
&& GET_MODE (x
) == promoted_mode
1939 && recog_memoized (insn
) >= 0)
1942 *loc
= replacement
->new = gen_reg_rtx (promoted_mode
);
1946 /* If X contains VAR, we need to unshare it here so that we update
1947 each occurrence separately. But all identical MEMs in one insn
1948 must be replaced with the same rtx because of the possibility of
1951 if (reg_mentioned_p (var
, x
))
1953 replacement
= find_fixup_replacement (replacements
, x
);
1954 if (replacement
->new == 0)
1955 replacement
->new = copy_most_rtx (x
, var
);
1957 *loc
= x
= replacement
->new;
1973 /* Note that in some cases those types of expressions are altered
1974 by optimize_bit_field, and do not survive to get here. */
1975 if (XEXP (x
, 0) == var
1976 || (GET_CODE (XEXP (x
, 0)) == SUBREG
1977 && SUBREG_REG (XEXP (x
, 0)) == var
))
1979 /* Get TEM as a valid MEM in the mode presently in the insn.
1981 We don't worry about the possibility of MATCH_DUP here; it
1982 is highly unlikely and would be tricky to handle. */
1985 if (GET_CODE (tem
) == SUBREG
)
1987 if (GET_MODE_BITSIZE (GET_MODE (tem
))
1988 > GET_MODE_BITSIZE (GET_MODE (var
)))
1990 replacement
= find_fixup_replacement (replacements
, var
);
1991 if (replacement
->new == 0)
1992 replacement
->new = gen_reg_rtx (GET_MODE (var
));
1993 SUBREG_REG (tem
) = replacement
->new;
1996 tem
= fixup_memory_subreg (tem
, insn
, 0);
1999 tem
= fixup_stack_1 (tem
, insn
);
2001 /* Unless we want to load from memory, get TEM into the proper mode
2002 for an extract from memory. This can only be done if the
2003 extract is at a constant position and length. */
2005 if (! flag_force_mem
&& GET_CODE (XEXP (x
, 1)) == CONST_INT
2006 && GET_CODE (XEXP (x
, 2)) == CONST_INT
2007 && ! mode_dependent_address_p (XEXP (tem
, 0))
2008 && ! MEM_VOLATILE_P (tem
))
2010 enum machine_mode wanted_mode
= VOIDmode
;
2011 enum machine_mode is_mode
= GET_MODE (tem
);
2012 HOST_WIDE_INT pos
= INTVAL (XEXP (x
, 2));
2015 if (GET_CODE (x
) == ZERO_EXTRACT
)
2018 = insn_data
[(int) CODE_FOR_extzv
].operand
[1].mode
;
2019 if (wanted_mode
== VOIDmode
)
2020 wanted_mode
= word_mode
;
2024 if (GET_CODE (x
) == SIGN_EXTRACT
)
2026 wanted_mode
= insn_data
[(int) CODE_FOR_extv
].operand
[1].mode
;
2027 if (wanted_mode
== VOIDmode
)
2028 wanted_mode
= word_mode
;
2031 /* If we have a narrower mode, we can do something. */
2032 if (wanted_mode
!= VOIDmode
2033 && GET_MODE_SIZE (wanted_mode
) < GET_MODE_SIZE (is_mode
))
2035 HOST_WIDE_INT offset
= pos
/ BITS_PER_UNIT
;
2036 rtx old_pos
= XEXP (x
, 2);
2039 /* If the bytes and bits are counted differently, we
2040 must adjust the offset. */
2041 if (BYTES_BIG_ENDIAN
!= BITS_BIG_ENDIAN
)
2042 offset
= (GET_MODE_SIZE (is_mode
)
2043 - GET_MODE_SIZE (wanted_mode
) - offset
);
2045 pos
%= GET_MODE_BITSIZE (wanted_mode
);
2047 newmem
= gen_rtx_MEM (wanted_mode
,
2048 plus_constant (XEXP (tem
, 0), offset
));
2049 RTX_UNCHANGING_P (newmem
) = RTX_UNCHANGING_P (tem
);
2050 MEM_COPY_ATTRIBUTES (newmem
, tem
);
2052 /* Make the change and see if the insn remains valid. */
2053 INSN_CODE (insn
) = -1;
2054 XEXP (x
, 0) = newmem
;
2055 XEXP (x
, 2) = GEN_INT (pos
);
2057 if (recog_memoized (insn
) >= 0)
2060 /* Otherwise, restore old position. XEXP (x, 0) will be
2062 XEXP (x
, 2) = old_pos
;
2066 /* If we get here, the bitfield extract insn can't accept a memory
2067 reference. Copy the input into a register. */
2069 tem1
= gen_reg_rtx (GET_MODE (tem
));
2070 emit_insn_before (gen_move_insn (tem1
, tem
), insn
);
2077 if (SUBREG_REG (x
) == var
)
2079 /* If this is a special SUBREG made because VAR was promoted
2080 from a wider mode, replace it with VAR and call ourself
2081 recursively, this time saying that the object previously
2082 had its current mode (by virtue of the SUBREG). */
2084 if (SUBREG_PROMOTED_VAR_P (x
))
2087 fixup_var_refs_1 (var
, GET_MODE (var
), loc
, insn
, replacements
);
2091 /* If this SUBREG makes VAR wider, it has become a paradoxical
2092 SUBREG with VAR in memory, but these aren't allowed at this
2093 stage of the compilation. So load VAR into a pseudo and take
2094 a SUBREG of that pseudo. */
2095 if (GET_MODE_SIZE (GET_MODE (x
)) > GET_MODE_SIZE (GET_MODE (var
)))
2097 replacement
= find_fixup_replacement (replacements
, var
);
2098 if (replacement
->new == 0)
2099 replacement
->new = gen_reg_rtx (GET_MODE (var
));
2100 SUBREG_REG (x
) = replacement
->new;
2104 /* See if we have already found a replacement for this SUBREG.
2105 If so, use it. Otherwise, make a MEM and see if the insn
2106 is recognized. If not, or if we should force MEM into a register,
2107 make a pseudo for this SUBREG. */
2108 replacement
= find_fixup_replacement (replacements
, x
);
2109 if (replacement
->new)
2111 *loc
= replacement
->new;
2115 replacement
->new = *loc
= fixup_memory_subreg (x
, insn
, 0);
2117 INSN_CODE (insn
) = -1;
2118 if (! flag_force_mem
&& recog_memoized (insn
) >= 0)
2121 *loc
= replacement
->new = gen_reg_rtx (GET_MODE (x
));
2127 /* First do special simplification of bit-field references. */
2128 if (GET_CODE (SET_DEST (x
)) == SIGN_EXTRACT
2129 || GET_CODE (SET_DEST (x
)) == ZERO_EXTRACT
)
2130 optimize_bit_field (x
, insn
, 0);
2131 if (GET_CODE (SET_SRC (x
)) == SIGN_EXTRACT
2132 || GET_CODE (SET_SRC (x
)) == ZERO_EXTRACT
)
2133 optimize_bit_field (x
, insn
, NULL_PTR
);
2135 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2136 into a register and then store it back out. */
2137 if (GET_CODE (SET_DEST (x
)) == ZERO_EXTRACT
2138 && GET_CODE (XEXP (SET_DEST (x
), 0)) == SUBREG
2139 && SUBREG_REG (XEXP (SET_DEST (x
), 0)) == var
2140 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x
), 0)))
2141 > GET_MODE_SIZE (GET_MODE (var
))))
2143 replacement
= find_fixup_replacement (replacements
, var
);
2144 if (replacement
->new == 0)
2145 replacement
->new = gen_reg_rtx (GET_MODE (var
));
2147 SUBREG_REG (XEXP (SET_DEST (x
), 0)) = replacement
->new;
2148 emit_insn_after (gen_move_insn (var
, replacement
->new), insn
);
2151 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2152 insn into a pseudo and store the low part of the pseudo into VAR. */
2153 if (GET_CODE (SET_DEST (x
)) == SUBREG
2154 && SUBREG_REG (SET_DEST (x
)) == var
2155 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x
)))
2156 > GET_MODE_SIZE (GET_MODE (var
))))
2158 SET_DEST (x
) = tem
= gen_reg_rtx (GET_MODE (SET_DEST (x
)));
2159 emit_insn_after (gen_move_insn (var
, gen_lowpart (GET_MODE (var
),
2166 rtx dest
= SET_DEST (x
);
2167 rtx src
= SET_SRC (x
);
2169 rtx outerdest
= dest
;
2172 while (GET_CODE (dest
) == SUBREG
|| GET_CODE (dest
) == STRICT_LOW_PART
2173 || GET_CODE (dest
) == SIGN_EXTRACT
2174 || GET_CODE (dest
) == ZERO_EXTRACT
)
2175 dest
= XEXP (dest
, 0);
2177 if (GET_CODE (src
) == SUBREG
)
2178 src
= XEXP (src
, 0);
2180 /* If VAR does not appear at the top level of the SET
2181 just scan the lower levels of the tree. */
2183 if (src
!= var
&& dest
!= var
)
2186 /* We will need to rerecognize this insn. */
2187 INSN_CODE (insn
) = -1;
2190 if (GET_CODE (outerdest
) == ZERO_EXTRACT
&& dest
== var
)
2192 /* Since this case will return, ensure we fixup all the
2194 fixup_var_refs_1 (var
, promoted_mode
, &XEXP (outerdest
, 1),
2195 insn
, replacements
);
2196 fixup_var_refs_1 (var
, promoted_mode
, &XEXP (outerdest
, 2),
2197 insn
, replacements
);
2198 fixup_var_refs_1 (var
, promoted_mode
, &SET_SRC (x
),
2199 insn
, replacements
);
2201 tem
= XEXP (outerdest
, 0);
2203 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2204 that may appear inside a ZERO_EXTRACT.
2205 This was legitimate when the MEM was a REG. */
2206 if (GET_CODE (tem
) == SUBREG
2207 && SUBREG_REG (tem
) == var
)
2208 tem
= fixup_memory_subreg (tem
, insn
, 0);
2210 tem
= fixup_stack_1 (tem
, insn
);
2212 if (GET_CODE (XEXP (outerdest
, 1)) == CONST_INT
2213 && GET_CODE (XEXP (outerdest
, 2)) == CONST_INT
2214 && ! mode_dependent_address_p (XEXP (tem
, 0))
2215 && ! MEM_VOLATILE_P (tem
))
2217 enum machine_mode wanted_mode
;
2218 enum machine_mode is_mode
= GET_MODE (tem
);
2219 HOST_WIDE_INT pos
= INTVAL (XEXP (outerdest
, 2));
2221 wanted_mode
= insn_data
[(int) CODE_FOR_insv
].operand
[0].mode
;
2222 if (wanted_mode
== VOIDmode
)
2223 wanted_mode
= word_mode
;
2225 /* If we have a narrower mode, we can do something. */
2226 if (GET_MODE_SIZE (wanted_mode
) < GET_MODE_SIZE (is_mode
))
2228 HOST_WIDE_INT offset
= pos
/ BITS_PER_UNIT
;
2229 rtx old_pos
= XEXP (outerdest
, 2);
2232 if (BYTES_BIG_ENDIAN
!= BITS_BIG_ENDIAN
)
2233 offset
= (GET_MODE_SIZE (is_mode
)
2234 - GET_MODE_SIZE (wanted_mode
) - offset
);
2236 pos
%= GET_MODE_BITSIZE (wanted_mode
);
2238 newmem
= gen_rtx_MEM (wanted_mode
,
2239 plus_constant (XEXP (tem
, 0),
2241 RTX_UNCHANGING_P (newmem
) = RTX_UNCHANGING_P (tem
);
2242 MEM_COPY_ATTRIBUTES (newmem
, tem
);
2244 /* Make the change and see if the insn remains valid. */
2245 INSN_CODE (insn
) = -1;
2246 XEXP (outerdest
, 0) = newmem
;
2247 XEXP (outerdest
, 2) = GEN_INT (pos
);
2249 if (recog_memoized (insn
) >= 0)
2252 /* Otherwise, restore old position. XEXP (x, 0) will be
2254 XEXP (outerdest
, 2) = old_pos
;
2258 /* If we get here, the bit-field store doesn't allow memory
2259 or isn't located at a constant position. Load the value into
2260 a register, do the store, and put it back into memory. */
2262 tem1
= gen_reg_rtx (GET_MODE (tem
));
2263 emit_insn_before (gen_move_insn (tem1
, tem
), insn
);
2264 emit_insn_after (gen_move_insn (tem
, tem1
), insn
);
2265 XEXP (outerdest
, 0) = tem1
;
2270 /* STRICT_LOW_PART is a no-op on memory references
2271 and it can cause combinations to be unrecognizable,
2274 if (dest
== var
&& GET_CODE (SET_DEST (x
)) == STRICT_LOW_PART
)
2275 SET_DEST (x
) = XEXP (SET_DEST (x
), 0);
2277 /* A valid insn to copy VAR into or out of a register
2278 must be left alone, to avoid an infinite loop here.
2279 If the reference to VAR is by a subreg, fix that up,
2280 since SUBREG is not valid for a memref.
2281 Also fix up the address of the stack slot.
2283 Note that we must not try to recognize the insn until
2284 after we know that we have valid addresses and no
2285 (subreg (mem ...) ...) constructs, since these interfere
2286 with determining the validity of the insn. */
2288 if ((SET_SRC (x
) == var
2289 || (GET_CODE (SET_SRC (x
)) == SUBREG
2290 && SUBREG_REG (SET_SRC (x
)) == var
))
2291 && (GET_CODE (SET_DEST (x
)) == REG
2292 || (GET_CODE (SET_DEST (x
)) == SUBREG
2293 && GET_CODE (SUBREG_REG (SET_DEST (x
))) == REG
))
2294 && GET_MODE (var
) == promoted_mode
2295 && x
== single_set (insn
))
2299 replacement
= find_fixup_replacement (replacements
, SET_SRC (x
));
2300 if (replacement
->new)
2301 SET_SRC (x
) = replacement
->new;
2302 else if (GET_CODE (SET_SRC (x
)) == SUBREG
)
2303 SET_SRC (x
) = replacement
->new
2304 = fixup_memory_subreg (SET_SRC (x
), insn
, 0);
2306 SET_SRC (x
) = replacement
->new
2307 = fixup_stack_1 (SET_SRC (x
), insn
);
2309 if (recog_memoized (insn
) >= 0)
2312 /* INSN is not valid, but we know that we want to
2313 copy SET_SRC (x) to SET_DEST (x) in some way. So
2314 we generate the move and see whether it requires more
2315 than one insn. If it does, we emit those insns and
2316 delete INSN. Otherwise, we an just replace the pattern
2317 of INSN; we have already verified above that INSN has
2318 no other function that to do X. */
2320 pat
= gen_move_insn (SET_DEST (x
), SET_SRC (x
));
2321 if (GET_CODE (pat
) == SEQUENCE
)
2323 emit_insn_after (pat
, insn
);
2324 PUT_CODE (insn
, NOTE
);
2325 NOTE_LINE_NUMBER (insn
) = NOTE_INSN_DELETED
;
2326 NOTE_SOURCE_FILE (insn
) = 0;
2329 PATTERN (insn
) = pat
;
2334 if ((SET_DEST (x
) == var
2335 || (GET_CODE (SET_DEST (x
)) == SUBREG
2336 && SUBREG_REG (SET_DEST (x
)) == var
))
2337 && (GET_CODE (SET_SRC (x
)) == REG
2338 || (GET_CODE (SET_SRC (x
)) == SUBREG
2339 && GET_CODE (SUBREG_REG (SET_SRC (x
))) == REG
))
2340 && GET_MODE (var
) == promoted_mode
2341 && x
== single_set (insn
))
2345 if (GET_CODE (SET_DEST (x
)) == SUBREG
)
2346 SET_DEST (x
) = fixup_memory_subreg (SET_DEST (x
), insn
, 0);
2348 SET_DEST (x
) = fixup_stack_1 (SET_DEST (x
), insn
);
2350 if (recog_memoized (insn
) >= 0)
2353 pat
= gen_move_insn (SET_DEST (x
), SET_SRC (x
));
2354 if (GET_CODE (pat
) == SEQUENCE
)
2356 emit_insn_after (pat
, insn
);
2357 PUT_CODE (insn
, NOTE
);
2358 NOTE_LINE_NUMBER (insn
) = NOTE_INSN_DELETED
;
2359 NOTE_SOURCE_FILE (insn
) = 0;
2362 PATTERN (insn
) = pat
;
2367 /* Otherwise, storing into VAR must be handled specially
2368 by storing into a temporary and copying that into VAR
2369 with a new insn after this one. Note that this case
2370 will be used when storing into a promoted scalar since
2371 the insn will now have different modes on the input
2372 and output and hence will be invalid (except for the case
2373 of setting it to a constant, which does not need any
2374 change if it is valid). We generate extra code in that case,
2375 but combine.c will eliminate it. */
2380 rtx fixeddest
= SET_DEST (x
);
2382 /* STRICT_LOW_PART can be discarded, around a MEM. */
2383 if (GET_CODE (fixeddest
) == STRICT_LOW_PART
)
2384 fixeddest
= XEXP (fixeddest
, 0);
2385 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2386 if (GET_CODE (fixeddest
) == SUBREG
)
2388 fixeddest
= fixup_memory_subreg (fixeddest
, insn
, 0);
2389 promoted_mode
= GET_MODE (fixeddest
);
2392 fixeddest
= fixup_stack_1 (fixeddest
, insn
);
2394 temp
= gen_reg_rtx (promoted_mode
);
2396 emit_insn_after (gen_move_insn (fixeddest
,
2397 gen_lowpart (GET_MODE (fixeddest
),
2401 SET_DEST (x
) = temp
;
2409 /* Nothing special about this RTX; fix its operands. */
2411 fmt
= GET_RTX_FORMAT (code
);
2412 for (i
= GET_RTX_LENGTH (code
) - 1; i
>= 0; i
--)
2415 fixup_var_refs_1 (var
, promoted_mode
, &XEXP (x
, i
), insn
, replacements
);
2416 else if (fmt
[i
] == 'E')
2419 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
2420 fixup_var_refs_1 (var
, promoted_mode
, &XVECEXP (x
, i
, j
),
2421 insn
, replacements
);
2426 /* Given X, an rtx of the form (SUBREG:m1 (MEM:m2 addr)),
2427 return an rtx (MEM:m1 newaddr) which is equivalent.
2428 If any insns must be emitted to compute NEWADDR, put them before INSN.
2430 UNCRITICAL nonzero means accept paradoxical subregs.
2431 This is used for subregs found inside REG_NOTES. */
2434 fixup_memory_subreg (x
, insn
, uncritical
)
2439 int offset
= SUBREG_WORD (x
) * UNITS_PER_WORD
;
2440 rtx addr
= XEXP (SUBREG_REG (x
), 0);
2441 enum machine_mode mode
= GET_MODE (x
);
2444 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2445 if (GET_MODE_SIZE (mode
) > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x
)))
2449 if (BYTES_BIG_ENDIAN
)
2450 offset
+= (MIN (UNITS_PER_WORD
, GET_MODE_SIZE (GET_MODE (SUBREG_REG (x
))))
2451 - MIN (UNITS_PER_WORD
, GET_MODE_SIZE (mode
)));
2452 addr
= plus_constant (addr
, offset
);
2453 if (!flag_force_addr
&& memory_address_p (mode
, addr
))
2454 /* Shortcut if no insns need be emitted. */
2455 return change_address (SUBREG_REG (x
), mode
, addr
);
2457 result
= change_address (SUBREG_REG (x
), mode
, addr
);
2458 emit_insn_before (gen_sequence (), insn
);
2463 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2464 Replace subexpressions of X in place.
2465 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2466 Otherwise return X, with its contents possibly altered.
2468 If any insns must be emitted to compute NEWADDR, put them before INSN.
2470 UNCRITICAL is as in fixup_memory_subreg. */
2473 walk_fixup_memory_subreg (x
, insn
, uncritical
)
2478 register enum rtx_code code
;
2479 register const char *fmt
;
2485 code
= GET_CODE (x
);
2487 if (code
== SUBREG
&& GET_CODE (SUBREG_REG (x
)) == MEM
)
2488 return fixup_memory_subreg (x
, insn
, uncritical
);
2490 /* Nothing special about this RTX; fix its operands. */
2492 fmt
= GET_RTX_FORMAT (code
);
2493 for (i
= GET_RTX_LENGTH (code
) - 1; i
>= 0; i
--)
2496 XEXP (x
, i
) = walk_fixup_memory_subreg (XEXP (x
, i
), insn
, uncritical
);
2497 else if (fmt
[i
] == 'E')
2500 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
2502 = walk_fixup_memory_subreg (XVECEXP (x
, i
, j
), insn
, uncritical
);
2508 /* For each memory ref within X, if it refers to a stack slot
2509 with an out of range displacement, put the address in a temp register
2510 (emitting new insns before INSN to load these registers)
2511 and alter the memory ref to use that register.
2512 Replace each such MEM rtx with a copy, to avoid clobberage. */
2515 fixup_stack_1 (x
, insn
)
2520 register RTX_CODE code
= GET_CODE (x
);
2521 register const char *fmt
;
2525 register rtx ad
= XEXP (x
, 0);
2526 /* If we have address of a stack slot but it's not valid
2527 (displacement is too large), compute the sum in a register. */
2528 if (GET_CODE (ad
) == PLUS
2529 && GET_CODE (XEXP (ad
, 0)) == REG
2530 && ((REGNO (XEXP (ad
, 0)) >= FIRST_VIRTUAL_REGISTER
2531 && REGNO (XEXP (ad
, 0)) <= LAST_VIRTUAL_REGISTER
)
2532 || REGNO (XEXP (ad
, 0)) == FRAME_POINTER_REGNUM
2533 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2534 || REGNO (XEXP (ad
, 0)) == HARD_FRAME_POINTER_REGNUM
2536 || REGNO (XEXP (ad
, 0)) == STACK_POINTER_REGNUM
2537 || REGNO (XEXP (ad
, 0)) == ARG_POINTER_REGNUM
2538 || XEXP (ad
, 0) == current_function_internal_arg_pointer
)
2539 && GET_CODE (XEXP (ad
, 1)) == CONST_INT
)
2542 if (memory_address_p (GET_MODE (x
), ad
))
2546 temp
= copy_to_reg (ad
);
2547 seq
= gen_sequence ();
2549 emit_insn_before (seq
, insn
);
2550 return change_address (x
, VOIDmode
, temp
);
2555 fmt
= GET_RTX_FORMAT (code
);
2556 for (i
= GET_RTX_LENGTH (code
) - 1; i
>= 0; i
--)
2559 XEXP (x
, i
) = fixup_stack_1 (XEXP (x
, i
), insn
);
2560 else if (fmt
[i
] == 'E')
2563 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
2564 XVECEXP (x
, i
, j
) = fixup_stack_1 (XVECEXP (x
, i
, j
), insn
);
2570 /* Optimization: a bit-field instruction whose field
2571 happens to be a byte or halfword in memory
2572 can be changed to a move instruction.
2574 We call here when INSN is an insn to examine or store into a bit-field.
2575 BODY is the SET-rtx to be altered.
2577 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2578 (Currently this is called only from function.c, and EQUIV_MEM
2582 optimize_bit_field (body
, insn
, equiv_mem
)
2587 register rtx bitfield
;
2590 enum machine_mode mode
;
2592 if (GET_CODE (SET_DEST (body
)) == SIGN_EXTRACT
2593 || GET_CODE (SET_DEST (body
)) == ZERO_EXTRACT
)
2594 bitfield
= SET_DEST (body
), destflag
= 1;
2596 bitfield
= SET_SRC (body
), destflag
= 0;
2598 /* First check that the field being stored has constant size and position
2599 and is in fact a byte or halfword suitably aligned. */
2601 if (GET_CODE (XEXP (bitfield
, 1)) == CONST_INT
2602 && GET_CODE (XEXP (bitfield
, 2)) == CONST_INT
2603 && ((mode
= mode_for_size (INTVAL (XEXP (bitfield
, 1)), MODE_INT
, 1))
2605 && INTVAL (XEXP (bitfield
, 2)) % INTVAL (XEXP (bitfield
, 1)) == 0)
2607 register rtx memref
= 0;
2609 /* Now check that the containing word is memory, not a register,
2610 and that it is safe to change the machine mode. */
2612 if (GET_CODE (XEXP (bitfield
, 0)) == MEM
)
2613 memref
= XEXP (bitfield
, 0);
2614 else if (GET_CODE (XEXP (bitfield
, 0)) == REG
2616 memref
= equiv_mem
[REGNO (XEXP (bitfield
, 0))];
2617 else if (GET_CODE (XEXP (bitfield
, 0)) == SUBREG
2618 && GET_CODE (SUBREG_REG (XEXP (bitfield
, 0))) == MEM
)
2619 memref
= SUBREG_REG (XEXP (bitfield
, 0));
2620 else if (GET_CODE (XEXP (bitfield
, 0)) == SUBREG
2622 && GET_CODE (SUBREG_REG (XEXP (bitfield
, 0))) == REG
)
2623 memref
= equiv_mem
[REGNO (SUBREG_REG (XEXP (bitfield
, 0)))];
2626 && ! mode_dependent_address_p (XEXP (memref
, 0))
2627 && ! MEM_VOLATILE_P (memref
))
2629 /* Now adjust the address, first for any subreg'ing
2630 that we are now getting rid of,
2631 and then for which byte of the word is wanted. */
2633 HOST_WIDE_INT offset
= INTVAL (XEXP (bitfield
, 2));
2636 /* Adjust OFFSET to count bits from low-address byte. */
2637 if (BITS_BIG_ENDIAN
!= BYTES_BIG_ENDIAN
)
2638 offset
= (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield
, 0)))
2639 - offset
- INTVAL (XEXP (bitfield
, 1)));
2641 /* Adjust OFFSET to count bytes from low-address byte. */
2642 offset
/= BITS_PER_UNIT
;
2643 if (GET_CODE (XEXP (bitfield
, 0)) == SUBREG
)
2645 offset
+= SUBREG_WORD (XEXP (bitfield
, 0)) * UNITS_PER_WORD
;
2646 if (BYTES_BIG_ENDIAN
)
2647 offset
-= (MIN (UNITS_PER_WORD
,
2648 GET_MODE_SIZE (GET_MODE (XEXP (bitfield
, 0))))
2649 - MIN (UNITS_PER_WORD
,
2650 GET_MODE_SIZE (GET_MODE (memref
))));
2654 memref
= change_address (memref
, mode
,
2655 plus_constant (XEXP (memref
, 0), offset
));
2656 insns
= get_insns ();
2658 emit_insns_before (insns
, insn
);
2660 /* Store this memory reference where
2661 we found the bit field reference. */
2665 validate_change (insn
, &SET_DEST (body
), memref
, 1);
2666 if (! CONSTANT_ADDRESS_P (SET_SRC (body
)))
2668 rtx src
= SET_SRC (body
);
2669 while (GET_CODE (src
) == SUBREG
2670 && SUBREG_WORD (src
) == 0)
2671 src
= SUBREG_REG (src
);
2672 if (GET_MODE (src
) != GET_MODE (memref
))
2673 src
= gen_lowpart (GET_MODE (memref
), SET_SRC (body
));
2674 validate_change (insn
, &SET_SRC (body
), src
, 1);
2676 else if (GET_MODE (SET_SRC (body
)) != VOIDmode
2677 && GET_MODE (SET_SRC (body
)) != GET_MODE (memref
))
2678 /* This shouldn't happen because anything that didn't have
2679 one of these modes should have got converted explicitly
2680 and then referenced through a subreg.
2681 This is so because the original bit-field was
2682 handled by agg_mode and so its tree structure had
2683 the same mode that memref now has. */
2688 rtx dest
= SET_DEST (body
);
2690 while (GET_CODE (dest
) == SUBREG
2691 && SUBREG_WORD (dest
) == 0
2692 && (GET_MODE_CLASS (GET_MODE (dest
))
2693 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest
))))
2694 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest
)))
2696 dest
= SUBREG_REG (dest
);
2698 validate_change (insn
, &SET_DEST (body
), dest
, 1);
2700 if (GET_MODE (dest
) == GET_MODE (memref
))
2701 validate_change (insn
, &SET_SRC (body
), memref
, 1);
2704 /* Convert the mem ref to the destination mode. */
2705 rtx newreg
= gen_reg_rtx (GET_MODE (dest
));
2708 convert_move (newreg
, memref
,
2709 GET_CODE (SET_SRC (body
)) == ZERO_EXTRACT
);
2713 validate_change (insn
, &SET_SRC (body
), newreg
, 1);
2717 /* See if we can convert this extraction or insertion into
2718 a simple move insn. We might not be able to do so if this
2719 was, for example, part of a PARALLEL.
2721 If we succeed, write out any needed conversions. If we fail,
2722 it is hard to guess why we failed, so don't do anything
2723 special; just let the optimization be suppressed. */
2725 if (apply_change_group () && seq
)
2726 emit_insns_before (seq
, insn
);
2731 /* These routines are responsible for converting virtual register references
2732 to the actual hard register references once RTL generation is complete.
2734 The following four variables are used for communication between the
2735 routines. They contain the offsets of the virtual registers from their
2736 respective hard registers. */
2738 static int in_arg_offset
;
2739 static int var_offset
;
2740 static int dynamic_offset
;
2741 static int out_arg_offset
;
2742 static int cfa_offset
;
2744 /* In most machines, the stack pointer register is equivalent to the bottom
2747 #ifndef STACK_POINTER_OFFSET
2748 #define STACK_POINTER_OFFSET 0
2751 /* If not defined, pick an appropriate default for the offset of dynamically
2752 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2753 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2755 #ifndef STACK_DYNAMIC_OFFSET
2757 /* The bottom of the stack points to the actual arguments. If
2758 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2759 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2760 stack space for register parameters is not pushed by the caller, but
2761 rather part of the fixed stack areas and hence not included in
2762 `current_function_outgoing_args_size'. Nevertheless, we must allow
2763 for it when allocating stack dynamic objects. */
2765 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2766 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2767 ((ACCUMULATE_OUTGOING_ARGS \
2768 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2769 + (STACK_POINTER_OFFSET)) \
2772 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2773 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2774 + (STACK_POINTER_OFFSET))
2778 /* On most machines, the CFA coincides with the first incoming parm. */
2780 #ifndef ARG_POINTER_CFA_OFFSET
2781 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2785 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just had
2786 its address taken. DECL is the decl for the object stored in the
2787 register, for later use if we do need to force REG into the stack.
2788 REG is overwritten by the MEM like in put_reg_into_stack. */
2791 gen_mem_addressof (reg
, decl
)
2795 tree type
= TREE_TYPE (decl
);
2796 rtx r
= gen_rtx_ADDRESSOF (Pmode
, gen_reg_rtx (GET_MODE (reg
)),
2799 /* If the original REG was a user-variable, then so is the REG whose
2800 address is being taken. Likewise for unchanging. */
2801 REG_USERVAR_P (XEXP (r
, 0)) = REG_USERVAR_P (reg
);
2802 RTX_UNCHANGING_P (XEXP (r
, 0)) = RTX_UNCHANGING_P (reg
);
2804 PUT_CODE (reg
, MEM
);
2805 PUT_MODE (reg
, DECL_MODE (decl
));
2807 MEM_VOLATILE_P (reg
) = TREE_SIDE_EFFECTS (decl
);
2808 MEM_SET_IN_STRUCT_P (reg
, AGGREGATE_TYPE_P (type
));
2809 MEM_ALIAS_SET (reg
) = get_alias_set (decl
);
2811 if (TREE_USED (decl
) || DECL_INITIAL (decl
) != 0)
2812 fixup_var_refs (reg
, GET_MODE (reg
), TREE_UNSIGNED (type
), 0);
2817 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2820 flush_addressof (decl
)
2823 if ((TREE_CODE (decl
) == PARM_DECL
|| TREE_CODE (decl
) == VAR_DECL
)
2824 && DECL_RTL (decl
) != 0
2825 && GET_CODE (DECL_RTL (decl
)) == MEM
2826 && GET_CODE (XEXP (DECL_RTL (decl
), 0)) == ADDRESSOF
2827 && GET_CODE (XEXP (XEXP (DECL_RTL (decl
), 0), 0)) == REG
)
2828 put_addressof_into_stack (XEXP (DECL_RTL (decl
), 0), 0);
2831 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2834 put_addressof_into_stack (r
, ht
)
2836 struct hash_table
*ht
;
2838 tree decl
= ADDRESSOF_DECL (r
);
2839 rtx reg
= XEXP (r
, 0);
2841 if (GET_CODE (reg
) != REG
)
2844 put_reg_into_stack (0, reg
, TREE_TYPE (decl
), GET_MODE (reg
),
2845 DECL_MODE (decl
), TREE_SIDE_EFFECTS (decl
),
2846 ADDRESSOF_REGNO (r
),
2847 TREE_USED (decl
) || DECL_INITIAL (decl
) != 0, ht
);
2850 /* List of replacements made below in purge_addressof_1 when creating
2851 bitfield insertions. */
2852 static rtx purge_bitfield_addressof_replacements
;
2854 /* List of replacements made below in purge_addressof_1 for patterns
2855 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2856 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2857 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2858 enough in complex cases, e.g. when some field values can be
2859 extracted by usage MEM with narrower mode. */
2860 static rtx purge_addressof_replacements
;
2862 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2863 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2864 the stack. If the function returns FALSE then the replacement could not
2868 purge_addressof_1 (loc
, insn
, force
, store
, ht
)
2872 struct hash_table
*ht
;
2878 boolean result
= true;
2880 /* Re-start here to avoid recursion in common cases. */
2887 code
= GET_CODE (x
);
2889 /* If we don't return in any of the cases below, we will recurse inside
2890 the RTX, which will normally result in any ADDRESSOF being forced into
2894 result
= purge_addressof_1 (&SET_DEST (x
), insn
, force
, 1, ht
);
2895 result
&= purge_addressof_1 (&SET_SRC (x
), insn
, force
, 0, ht
);
2899 else if (code
== ADDRESSOF
&& GET_CODE (XEXP (x
, 0)) == MEM
)
2901 /* We must create a copy of the rtx because it was created by
2902 overwriting a REG rtx which is always shared. */
2903 rtx sub
= copy_rtx (XEXP (XEXP (x
, 0), 0));
2906 if (validate_change (insn
, loc
, sub
, 0)
2907 || validate_replace_rtx (x
, sub
, insn
))
2911 sub
= force_operand (sub
, NULL_RTX
);
2912 if (! validate_change (insn
, loc
, sub
, 0)
2913 && ! validate_replace_rtx (x
, sub
, insn
))
2916 insns
= gen_sequence ();
2918 emit_insn_before (insns
, insn
);
2922 else if (code
== MEM
&& GET_CODE (XEXP (x
, 0)) == ADDRESSOF
&& ! force
)
2924 rtx sub
= XEXP (XEXP (x
, 0), 0);
2927 if (GET_CODE (sub
) == MEM
)
2929 sub2
= gen_rtx_MEM (GET_MODE (x
), copy_rtx (XEXP (sub
, 0)));
2930 MEM_COPY_ATTRIBUTES (sub2
, sub
);
2931 RTX_UNCHANGING_P (sub2
) = RTX_UNCHANGING_P (sub
);
2934 else if (GET_CODE (sub
) == REG
2935 && (MEM_VOLATILE_P (x
) || GET_MODE (x
) == BLKmode
))
2937 else if (GET_CODE (sub
) == REG
&& GET_MODE (x
) != GET_MODE (sub
))
2939 int size_x
, size_sub
;
2943 /* When processing REG_NOTES look at the list of
2944 replacements done on the insn to find the register that X
2948 for (tem
= purge_bitfield_addressof_replacements
;
2950 tem
= XEXP (XEXP (tem
, 1), 1))
2951 if (rtx_equal_p (x
, XEXP (tem
, 0)))
2953 *loc
= XEXP (XEXP (tem
, 1), 0);
2957 /* See comment for purge_addressof_replacements. */
2958 for (tem
= purge_addressof_replacements
;
2960 tem
= XEXP (XEXP (tem
, 1), 1))
2961 if (rtx_equal_p (XEXP (x
, 0), XEXP (tem
, 0)))
2963 rtx z
= XEXP (XEXP (tem
, 1), 0);
2965 if (GET_MODE (x
) == GET_MODE (z
)
2966 || (GET_CODE (XEXP (XEXP (tem
, 1), 0)) != REG
2967 && GET_CODE (XEXP (XEXP (tem
, 1), 0)) != SUBREG
))
2970 /* It can happen that the note may speak of things
2971 in a wider (or just different) mode than the
2972 code did. This is especially true of
2975 if (GET_CODE (z
) == SUBREG
&& SUBREG_WORD (z
) == 0)
2978 if (GET_MODE_SIZE (GET_MODE (x
)) > UNITS_PER_WORD
2979 && (GET_MODE_SIZE (GET_MODE (x
))
2980 > GET_MODE_SIZE (GET_MODE (z
))))
2982 /* This can occur as a result in invalid
2983 pointer casts, e.g. float f; ...
2984 *(long long int *)&f.
2985 ??? We could emit a warning here, but
2986 without a line number that wouldn't be
2988 z
= gen_rtx_SUBREG (GET_MODE (x
), z
, 0);
2991 z
= gen_lowpart (GET_MODE (x
), z
);
2997 /* Sometimes we may not be able to find the replacement. For
2998 example when the original insn was a MEM in a wider mode,
2999 and the note is part of a sign extension of a narrowed
3000 version of that MEM. Gcc testcase compile/990829-1.c can
3001 generate an example of this siutation. Rather than complain
3002 we return false, which will prompt our caller to remove the
3007 size_x
= GET_MODE_BITSIZE (GET_MODE (x
));
3008 size_sub
= GET_MODE_BITSIZE (GET_MODE (sub
));
3010 /* Don't even consider working with paradoxical subregs,
3011 or the moral equivalent seen here. */
3012 if (size_x
<= size_sub
3013 && int_mode_for_mode (GET_MODE (sub
)) != BLKmode
)
3015 /* Do a bitfield insertion to mirror what would happen
3022 rtx p
= PREV_INSN (insn
);
3025 val
= gen_reg_rtx (GET_MODE (x
));
3026 if (! validate_change (insn
, loc
, val
, 0))
3028 /* Discard the current sequence and put the
3029 ADDRESSOF on stack. */
3033 seq
= gen_sequence ();
3035 emit_insn_before (seq
, insn
);
3036 compute_insns_for_mem (p
? NEXT_INSN (p
) : get_insns (),
3040 store_bit_field (sub
, size_x
, 0, GET_MODE (x
),
3041 val
, GET_MODE_SIZE (GET_MODE (sub
)),
3042 GET_MODE_ALIGNMENT (GET_MODE (sub
)));
3044 /* Make sure to unshare any shared rtl that store_bit_field
3045 might have created. */
3046 unshare_all_rtl_again (get_insns ());
3048 seq
= gen_sequence ();
3050 p
= emit_insn_after (seq
, insn
);
3051 if (NEXT_INSN (insn
))
3052 compute_insns_for_mem (NEXT_INSN (insn
),
3053 p
? NEXT_INSN (p
) : NULL_RTX
,
3058 rtx p
= PREV_INSN (insn
);
3061 val
= extract_bit_field (sub
, size_x
, 0, 1, NULL_RTX
,
3062 GET_MODE (x
), GET_MODE (x
),
3063 GET_MODE_SIZE (GET_MODE (sub
)),
3064 GET_MODE_SIZE (GET_MODE (sub
)));
3066 if (! validate_change (insn
, loc
, val
, 0))
3068 /* Discard the current sequence and put the
3069 ADDRESSOF on stack. */
3074 seq
= gen_sequence ();
3076 emit_insn_before (seq
, insn
);
3077 compute_insns_for_mem (p
? NEXT_INSN (p
) : get_insns (),
3081 /* Remember the replacement so that the same one can be done
3082 on the REG_NOTES. */
3083 purge_bitfield_addressof_replacements
3084 = gen_rtx_EXPR_LIST (VOIDmode
, x
,
3087 purge_bitfield_addressof_replacements
));
3089 /* We replaced with a reg -- all done. */
3094 else if (validate_change (insn
, loc
, sub
, 0))
3096 /* Remember the replacement so that the same one can be done
3097 on the REG_NOTES. */
3098 if (GET_CODE (sub
) == REG
|| GET_CODE (sub
) == SUBREG
)
3102 for (tem
= purge_addressof_replacements
;
3104 tem
= XEXP (XEXP (tem
, 1), 1))
3105 if (rtx_equal_p (XEXP (x
, 0), XEXP (tem
, 0)))
3107 XEXP (XEXP (tem
, 1), 0) = sub
;
3110 purge_addressof_replacements
3111 = gen_rtx (EXPR_LIST
, VOIDmode
, XEXP (x
, 0),
3112 gen_rtx_EXPR_LIST (VOIDmode
, sub
,
3113 purge_addressof_replacements
));
3119 /* else give up and put it into the stack */
3122 else if (code
== ADDRESSOF
)
3124 put_addressof_into_stack (x
, ht
);
3127 else if (code
== SET
)
3129 result
= purge_addressof_1 (&SET_DEST (x
), insn
, force
, 1, ht
);
3130 result
&= purge_addressof_1 (&SET_SRC (x
), insn
, force
, 0, ht
);
3134 /* Scan all subexpressions. */
3135 fmt
= GET_RTX_FORMAT (code
);
3136 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
3139 result
&= purge_addressof_1 (&XEXP (x
, i
), insn
, force
, 0, ht
);
3140 else if (*fmt
== 'E')
3141 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
3142 result
&= purge_addressof_1 (&XVECEXP (x
, i
, j
), insn
, force
, 0, ht
);
3148 /* Return a new hash table entry in HT. */
3150 static struct hash_entry
*
3151 insns_for_mem_newfunc (he
, ht
, k
)
3152 struct hash_entry
*he
;
3153 struct hash_table
*ht
;
3154 hash_table_key k ATTRIBUTE_UNUSED
;
3156 struct insns_for_mem_entry
*ifmhe
;
3160 ifmhe
= ((struct insns_for_mem_entry
*)
3161 hash_allocate (ht
, sizeof (struct insns_for_mem_entry
)));
3162 ifmhe
->insns
= NULL_RTX
;
3167 /* Return a hash value for K, a REG. */
3169 static unsigned long
3170 insns_for_mem_hash (k
)
3173 /* K is really a RTX. Just use the address as the hash value. */
3174 return (unsigned long) k
;
3177 /* Return non-zero if K1 and K2 (two REGs) are the same. */
3180 insns_for_mem_comp (k1
, k2
)
3187 struct insns_for_mem_walk_info
{
3188 /* The hash table that we are using to record which INSNs use which
3190 struct hash_table
*ht
;
3192 /* The INSN we are currently proessing. */
3195 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3196 to find the insns that use the REGs in the ADDRESSOFs. */
3200 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3201 that might be used in an ADDRESSOF expression, record this INSN in
3202 the hash table given by DATA (which is really a pointer to an
3203 insns_for_mem_walk_info structure). */
3206 insns_for_mem_walk (r
, data
)
3210 struct insns_for_mem_walk_info
*ifmwi
3211 = (struct insns_for_mem_walk_info
*) data
;
3213 if (ifmwi
->pass
== 0 && *r
&& GET_CODE (*r
) == ADDRESSOF
3214 && GET_CODE (XEXP (*r
, 0)) == REG
)
3215 hash_lookup (ifmwi
->ht
, XEXP (*r
, 0), /*create=*/1, /*copy=*/0);
3216 else if (ifmwi
->pass
== 1 && *r
&& GET_CODE (*r
) == REG
)
3218 /* Lookup this MEM in the hashtable, creating it if necessary. */
3219 struct insns_for_mem_entry
*ifme
3220 = (struct insns_for_mem_entry
*) hash_lookup (ifmwi
->ht
,
3225 /* If we have not already recorded this INSN, do so now. Since
3226 we process the INSNs in order, we know that if we have
3227 recorded it it must be at the front of the list. */
3228 if (ifme
&& (!ifme
->insns
|| XEXP (ifme
->insns
, 0) != ifmwi
->insn
))
3230 /* We do the allocation on the same obstack as is used for
3231 the hash table since this memory will not be used once
3232 the hash table is deallocated. */
3233 push_obstacks (&ifmwi
->ht
->memory
, &ifmwi
->ht
->memory
);
3234 ifme
->insns
= gen_rtx_EXPR_LIST (VOIDmode
, ifmwi
->insn
,
3243 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3244 which REGs in HT. */
3247 compute_insns_for_mem (insns
, last_insn
, ht
)
3250 struct hash_table
*ht
;
3253 struct insns_for_mem_walk_info ifmwi
;
3256 for (ifmwi
.pass
= 0; ifmwi
.pass
< 2; ++ifmwi
.pass
)
3257 for (insn
= insns
; insn
!= last_insn
; insn
= NEXT_INSN (insn
))
3258 if (GET_RTX_CLASS (GET_CODE (insn
)) == 'i')
3261 for_each_rtx (&insn
, insns_for_mem_walk
, &ifmwi
);
3265 /* Helper function for purge_addressof called through for_each_rtx.
3266 Returns true iff the rtl is an ADDRESSOF. */
3268 is_addressof (rtl
, data
)
3270 void * data ATTRIBUTE_UNUSED
;
3272 return GET_CODE (* rtl
) == ADDRESSOF
;
3275 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3276 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3280 purge_addressof (insns
)
3284 struct hash_table ht
;
3286 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3287 requires a fixup pass over the instruction stream to correct
3288 INSNs that depended on the REG being a REG, and not a MEM. But,
3289 these fixup passes are slow. Furthermore, most MEMs are not
3290 mentioned in very many instructions. So, we speed up the process
3291 by pre-calculating which REGs occur in which INSNs; that allows
3292 us to perform the fixup passes much more quickly. */
3293 hash_table_init (&ht
,
3294 insns_for_mem_newfunc
,
3296 insns_for_mem_comp
);
3297 compute_insns_for_mem (insns
, NULL_RTX
, &ht
);
3299 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
3300 if (GET_CODE (insn
) == INSN
|| GET_CODE (insn
) == JUMP_INSN
3301 || GET_CODE (insn
) == CALL_INSN
)
3303 if (! purge_addressof_1 (&PATTERN (insn
), insn
,
3304 asm_noperands (PATTERN (insn
)) > 0, 0, &ht
))
3305 /* If we could not replace the ADDRESSOFs in the insn,
3306 something is wrong. */
3309 if (! purge_addressof_1 (®_NOTES (insn
), NULL_RTX
, 0, 0, &ht
))
3311 /* If we could not replace the ADDRESSOFs in the insn's notes,
3312 we can just remove the offending notes instead. */
3315 for (note
= REG_NOTES (insn
); note
; note
= XEXP (note
, 1))
3317 /* If we find a REG_RETVAL note then the insn is a libcall.
3318 Such insns must have REG_EQUAL notes as well, in order
3319 for later passes of the compiler to work. So it is not
3320 safe to delete the notes here, and instead we abort. */
3321 if (REG_NOTE_KIND (note
) == REG_RETVAL
)
3323 if (for_each_rtx (& note
, is_addressof
, NULL
))
3324 remove_note (insn
, note
);
3330 hash_table_free (&ht
);
3331 purge_bitfield_addressof_replacements
= 0;
3332 purge_addressof_replacements
= 0;
3334 /* REGs are shared. purge_addressof will destructively replace a REG
3335 with a MEM, which creates shared MEMs.
3337 Unfortunately, the children of put_reg_into_stack assume that MEMs
3338 referring to the same stack slot are shared (fixup_var_refs and
3339 the associated hash table code).
3341 So, we have to do another unsharing pass after we have flushed any
3342 REGs that had their address taken into the stack.
3344 It may be worth tracking whether or not we converted any REGs into
3345 MEMs to avoid this overhead when it is not needed. */
3346 unshare_all_rtl_again (get_insns ());
3349 /* Pass through the INSNS of function FNDECL and convert virtual register
3350 references to hard register references. */
3353 instantiate_virtual_regs (fndecl
, insns
)
3360 /* Compute the offsets to use for this function. */
3361 in_arg_offset
= FIRST_PARM_OFFSET (fndecl
);
3362 var_offset
= STARTING_FRAME_OFFSET
;
3363 dynamic_offset
= STACK_DYNAMIC_OFFSET (fndecl
);
3364 out_arg_offset
= STACK_POINTER_OFFSET
;
3365 cfa_offset
= ARG_POINTER_CFA_OFFSET (fndecl
);
3367 /* Scan all variables and parameters of this function. For each that is
3368 in memory, instantiate all virtual registers if the result is a valid
3369 address. If not, we do it later. That will handle most uses of virtual
3370 regs on many machines. */
3371 instantiate_decls (fndecl
, 1);
3373 /* Initialize recognition, indicating that volatile is OK. */
3376 /* Scan through all the insns, instantiating every virtual register still
3378 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
3379 if (GET_CODE (insn
) == INSN
|| GET_CODE (insn
) == JUMP_INSN
3380 || GET_CODE (insn
) == CALL_INSN
)
3382 instantiate_virtual_regs_1 (&PATTERN (insn
), insn
, 1);
3383 instantiate_virtual_regs_1 (®_NOTES (insn
), NULL_RTX
, 0);
3386 /* Instantiate the stack slots for the parm registers, for later use in
3387 addressof elimination. */
3388 for (i
= 0; i
< max_parm_reg
; ++i
)
3389 if (parm_reg_stack_loc
[i
])
3390 instantiate_virtual_regs_1 (&parm_reg_stack_loc
[i
], NULL_RTX
, 0);
3392 /* Now instantiate the remaining register equivalences for debugging info.
3393 These will not be valid addresses. */
3394 instantiate_decls (fndecl
, 0);
3396 /* Indicate that, from now on, assign_stack_local should use
3397 frame_pointer_rtx. */
3398 virtuals_instantiated
= 1;
3401 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3402 all virtual registers in their DECL_RTL's.
3404 If VALID_ONLY, do this only if the resulting address is still valid.
3405 Otherwise, always do it. */
3408 instantiate_decls (fndecl
, valid_only
)
3414 if (DECL_SAVED_INSNS (fndecl
))
3415 /* When compiling an inline function, the obstack used for
3416 rtl allocation is the maybepermanent_obstack. Calling
3417 `resume_temporary_allocation' switches us back to that
3418 obstack while we process this function's parameters. */
3419 resume_temporary_allocation ();
3421 /* Process all parameters of the function. */
3422 for (decl
= DECL_ARGUMENTS (fndecl
); decl
; decl
= TREE_CHAIN (decl
))
3424 HOST_WIDE_INT size
= int_size_in_bytes (TREE_TYPE (decl
));
3426 instantiate_decl (DECL_RTL (decl
), size
, valid_only
);
3428 /* If the parameter was promoted, then the incoming RTL mode may be
3429 larger than the declared type size. We must use the larger of
3431 size
= MAX (GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl
))), size
);
3432 instantiate_decl (DECL_INCOMING_RTL (decl
), size
, valid_only
);
3435 /* Now process all variables defined in the function or its subblocks. */
3436 instantiate_decls_1 (DECL_INITIAL (fndecl
), valid_only
);
3438 if (DECL_INLINE (fndecl
) || DECL_DEFER_OUTPUT (fndecl
))
3440 /* Save all rtl allocated for this function by raising the
3441 high-water mark on the maybepermanent_obstack. */
3443 /* All further rtl allocation is now done in the current_obstack. */
3444 rtl_in_current_obstack ();
3448 /* Subroutine of instantiate_decls: Process all decls in the given
3449 BLOCK node and all its subblocks. */
3452 instantiate_decls_1 (let
, valid_only
)
3458 for (t
= BLOCK_VARS (let
); t
; t
= TREE_CHAIN (t
))
3459 instantiate_decl (DECL_RTL (t
), int_size_in_bytes (TREE_TYPE (t
)),
3462 /* Process all subblocks. */
3463 for (t
= BLOCK_SUBBLOCKS (let
); t
; t
= TREE_CHAIN (t
))
3464 instantiate_decls_1 (t
, valid_only
);
3467 /* Subroutine of the preceding procedures: Given RTL representing a
3468 decl and the size of the object, do any instantiation required.
3470 If VALID_ONLY is non-zero, it means that the RTL should only be
3471 changed if the new address is valid. */
3474 instantiate_decl (x
, size
, valid_only
)
3479 enum machine_mode mode
;
3482 /* If this is not a MEM, no need to do anything. Similarly if the
3483 address is a constant or a register that is not a virtual register. */
3485 if (x
== 0 || GET_CODE (x
) != MEM
)
3489 if (CONSTANT_P (addr
)
3490 || (GET_CODE (addr
) == ADDRESSOF
&& GET_CODE (XEXP (addr
, 0)) == REG
)
3491 || (GET_CODE (addr
) == REG
3492 && (REGNO (addr
) < FIRST_VIRTUAL_REGISTER
3493 || REGNO (addr
) > LAST_VIRTUAL_REGISTER
)))
3496 /* If we should only do this if the address is valid, copy the address.
3497 We need to do this so we can undo any changes that might make the
3498 address invalid. This copy is unfortunate, but probably can't be
3502 addr
= copy_rtx (addr
);
3504 instantiate_virtual_regs_1 (&addr
, NULL_RTX
, 0);
3506 if (valid_only
&& size
>= 0)
3508 unsigned HOST_WIDE_INT decl_size
= size
;
3510 /* Now verify that the resulting address is valid for every integer or
3511 floating-point mode up to and including SIZE bytes long. We do this
3512 since the object might be accessed in any mode and frame addresses
3515 for (mode
= GET_CLASS_NARROWEST_MODE (MODE_INT
);
3516 mode
!= VOIDmode
&& GET_MODE_SIZE (mode
) <= decl_size
;
3517 mode
= GET_MODE_WIDER_MODE (mode
))
3518 if (! memory_address_p (mode
, addr
))
3521 for (mode
= GET_CLASS_NARROWEST_MODE (MODE_FLOAT
);
3522 mode
!= VOIDmode
&& GET_MODE_SIZE (mode
) <= decl_size
;
3523 mode
= GET_MODE_WIDER_MODE (mode
))
3524 if (! memory_address_p (mode
, addr
))
3528 /* Put back the address now that we have updated it and we either know
3529 it is valid or we don't care whether it is valid. */
3534 /* Given a pointer to a piece of rtx and an optional pointer to the
3535 containing object, instantiate any virtual registers present in it.
3537 If EXTRA_INSNS, we always do the replacement and generate
3538 any extra insns before OBJECT. If it zero, we do nothing if replacement
3541 Return 1 if we either had nothing to do or if we were able to do the
3542 needed replacement. Return 0 otherwise; we only return zero if
3543 EXTRA_INSNS is zero.
3545 We first try some simple transformations to avoid the creation of extra
3549 instantiate_virtual_regs_1 (loc
, object
, extra_insns
)
3557 HOST_WIDE_INT offset
= 0;
3563 /* Re-start here to avoid recursion in common cases. */
3570 code
= GET_CODE (x
);
3572 /* Check for some special cases. */
3589 /* We are allowed to set the virtual registers. This means that
3590 the actual register should receive the source minus the
3591 appropriate offset. This is used, for example, in the handling
3592 of non-local gotos. */
3593 if (SET_DEST (x
) == virtual_incoming_args_rtx
)
3594 new = arg_pointer_rtx
, offset
= - in_arg_offset
;
3595 else if (SET_DEST (x
) == virtual_stack_vars_rtx
)
3596 new = frame_pointer_rtx
, offset
= - var_offset
;
3597 else if (SET_DEST (x
) == virtual_stack_dynamic_rtx
)
3598 new = stack_pointer_rtx
, offset
= - dynamic_offset
;
3599 else if (SET_DEST (x
) == virtual_outgoing_args_rtx
)
3600 new = stack_pointer_rtx
, offset
= - out_arg_offset
;
3601 else if (SET_DEST (x
) == virtual_cfa_rtx
)
3602 new = arg_pointer_rtx
, offset
= - cfa_offset
;
3606 rtx src
= SET_SRC (x
);
3608 instantiate_virtual_regs_1 (&src
, NULL_RTX
, 0);
3610 /* The only valid sources here are PLUS or REG. Just do
3611 the simplest possible thing to handle them. */
3612 if (GET_CODE (src
) != REG
&& GET_CODE (src
) != PLUS
)
3616 if (GET_CODE (src
) != REG
)
3617 temp
= force_operand (src
, NULL_RTX
);
3620 temp
= force_operand (plus_constant (temp
, offset
), NULL_RTX
);
3624 emit_insns_before (seq
, object
);
3627 if (! validate_change (object
, &SET_SRC (x
), temp
, 0)
3634 instantiate_virtual_regs_1 (&SET_DEST (x
), object
, extra_insns
);
3639 /* Handle special case of virtual register plus constant. */
3640 if (CONSTANT_P (XEXP (x
, 1)))
3642 rtx old
, new_offset
;
3644 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3645 if (GET_CODE (XEXP (x
, 0)) == PLUS
)
3647 rtx inner
= XEXP (XEXP (x
, 0), 0);
3649 if (inner
== virtual_incoming_args_rtx
)
3650 new = arg_pointer_rtx
, offset
= in_arg_offset
;
3651 else if (inner
== virtual_stack_vars_rtx
)
3652 new = frame_pointer_rtx
, offset
= var_offset
;
3653 else if (inner
== virtual_stack_dynamic_rtx
)
3654 new = stack_pointer_rtx
, offset
= dynamic_offset
;
3655 else if (inner
== virtual_outgoing_args_rtx
)
3656 new = stack_pointer_rtx
, offset
= out_arg_offset
;
3657 else if (inner
== virtual_cfa_rtx
)
3658 new = arg_pointer_rtx
, offset
= cfa_offset
;
3665 instantiate_virtual_regs_1 (&XEXP (XEXP (x
, 0), 1), object
,
3667 new = gen_rtx_PLUS (Pmode
, new, XEXP (XEXP (x
, 0), 1));
3670 else if (XEXP (x
, 0) == virtual_incoming_args_rtx
)
3671 new = arg_pointer_rtx
, offset
= in_arg_offset
;
3672 else if (XEXP (x
, 0) == virtual_stack_vars_rtx
)
3673 new = frame_pointer_rtx
, offset
= var_offset
;
3674 else if (XEXP (x
, 0) == virtual_stack_dynamic_rtx
)
3675 new = stack_pointer_rtx
, offset
= dynamic_offset
;
3676 else if (XEXP (x
, 0) == virtual_outgoing_args_rtx
)
3677 new = stack_pointer_rtx
, offset
= out_arg_offset
;
3678 else if (XEXP (x
, 0) == virtual_cfa_rtx
)
3679 new = arg_pointer_rtx
, offset
= cfa_offset
;
3682 /* We know the second operand is a constant. Unless the
3683 first operand is a REG (which has been already checked),
3684 it needs to be checked. */
3685 if (GET_CODE (XEXP (x
, 0)) != REG
)
3693 new_offset
= plus_constant (XEXP (x
, 1), offset
);
3695 /* If the new constant is zero, try to replace the sum with just
3697 if (new_offset
== const0_rtx
3698 && validate_change (object
, loc
, new, 0))
3701 /* Next try to replace the register and new offset.
3702 There are two changes to validate here and we can't assume that
3703 in the case of old offset equals new just changing the register
3704 will yield a valid insn. In the interests of a little efficiency,
3705 however, we only call validate change once (we don't queue up the
3706 changes and then call apply_change_group). */
3710 ? ! validate_change (object
, &XEXP (x
, 0), new, 0)
3711 : (XEXP (x
, 0) = new,
3712 ! validate_change (object
, &XEXP (x
, 1), new_offset
, 0)))
3720 /* Otherwise copy the new constant into a register and replace
3721 constant with that register. */
3722 temp
= gen_reg_rtx (Pmode
);
3724 if (validate_change (object
, &XEXP (x
, 1), temp
, 0))
3725 emit_insn_before (gen_move_insn (temp
, new_offset
), object
);
3728 /* If that didn't work, replace this expression with a
3729 register containing the sum. */
3732 new = gen_rtx_PLUS (Pmode
, new, new_offset
);
3735 temp
= force_operand (new, NULL_RTX
);
3739 emit_insns_before (seq
, object
);
3740 if (! validate_change (object
, loc
, temp
, 0)
3741 && ! validate_replace_rtx (x
, temp
, object
))
3749 /* Fall through to generic two-operand expression case. */
3755 case DIV
: case UDIV
:
3756 case MOD
: case UMOD
:
3757 case AND
: case IOR
: case XOR
:
3758 case ROTATERT
: case ROTATE
:
3759 case ASHIFTRT
: case LSHIFTRT
: case ASHIFT
:
3761 case GE
: case GT
: case GEU
: case GTU
:
3762 case LE
: case LT
: case LEU
: case LTU
:
3763 if (XEXP (x
, 1) && ! CONSTANT_P (XEXP (x
, 1)))
3764 instantiate_virtual_regs_1 (&XEXP (x
, 1), object
, extra_insns
);
3769 /* Most cases of MEM that convert to valid addresses have already been
3770 handled by our scan of decls. The only special handling we
3771 need here is to make a copy of the rtx to ensure it isn't being
3772 shared if we have to change it to a pseudo.
3774 If the rtx is a simple reference to an address via a virtual register,
3775 it can potentially be shared. In such cases, first try to make it
3776 a valid address, which can also be shared. Otherwise, copy it and
3779 First check for common cases that need no processing. These are
3780 usually due to instantiation already being done on a previous instance
3784 if (CONSTANT_ADDRESS_P (temp
)
3785 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3786 || temp
== arg_pointer_rtx
3788 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3789 || temp
== hard_frame_pointer_rtx
3791 || temp
== frame_pointer_rtx
)
3794 if (GET_CODE (temp
) == PLUS
3795 && CONSTANT_ADDRESS_P (XEXP (temp
, 1))
3796 && (XEXP (temp
, 0) == frame_pointer_rtx
3797 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3798 || XEXP (temp
, 0) == hard_frame_pointer_rtx
3800 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3801 || XEXP (temp
, 0) == arg_pointer_rtx
3806 if (temp
== virtual_stack_vars_rtx
3807 || temp
== virtual_incoming_args_rtx
3808 || (GET_CODE (temp
) == PLUS
3809 && CONSTANT_ADDRESS_P (XEXP (temp
, 1))
3810 && (XEXP (temp
, 0) == virtual_stack_vars_rtx
3811 || XEXP (temp
, 0) == virtual_incoming_args_rtx
)))
3813 /* This MEM may be shared. If the substitution can be done without
3814 the need to generate new pseudos, we want to do it in place
3815 so all copies of the shared rtx benefit. The call below will
3816 only make substitutions if the resulting address is still
3819 Note that we cannot pass X as the object in the recursive call
3820 since the insn being processed may not allow all valid
3821 addresses. However, if we were not passed on object, we can
3822 only modify X without copying it if X will have a valid
3825 ??? Also note that this can still lose if OBJECT is an insn that
3826 has less restrictions on an address that some other insn.
3827 In that case, we will modify the shared address. This case
3828 doesn't seem very likely, though. One case where this could
3829 happen is in the case of a USE or CLOBBER reference, but we
3830 take care of that below. */
3832 if (instantiate_virtual_regs_1 (&XEXP (x
, 0),
3833 object
? object
: x
, 0))
3836 /* Otherwise make a copy and process that copy. We copy the entire
3837 RTL expression since it might be a PLUS which could also be
3839 *loc
= x
= copy_rtx (x
);
3842 /* Fall through to generic unary operation case. */
3844 case STRICT_LOW_PART
:
3846 case PRE_DEC
: case PRE_INC
: case POST_DEC
: case POST_INC
:
3847 case SIGN_EXTEND
: case ZERO_EXTEND
:
3848 case TRUNCATE
: case FLOAT_EXTEND
: case FLOAT_TRUNCATE
:
3849 case FLOAT
: case FIX
:
3850 case UNSIGNED_FIX
: case UNSIGNED_FLOAT
:
3854 /* These case either have just one operand or we know that we need not
3855 check the rest of the operands. */
3861 /* If the operand is a MEM, see if the change is a valid MEM. If not,
3862 go ahead and make the invalid one, but do it to a copy. For a REG,
3863 just make the recursive call, since there's no chance of a problem. */
3865 if ((GET_CODE (XEXP (x
, 0)) == MEM
3866 && instantiate_virtual_regs_1 (&XEXP (XEXP (x
, 0), 0), XEXP (x
, 0),
3868 || (GET_CODE (XEXP (x
, 0)) == REG
3869 && instantiate_virtual_regs_1 (&XEXP (x
, 0), object
, 0)))
3872 XEXP (x
, 0) = copy_rtx (XEXP (x
, 0));
3877 /* Try to replace with a PLUS. If that doesn't work, compute the sum
3878 in front of this insn and substitute the temporary. */
3879 if (x
== virtual_incoming_args_rtx
)
3880 new = arg_pointer_rtx
, offset
= in_arg_offset
;
3881 else if (x
== virtual_stack_vars_rtx
)
3882 new = frame_pointer_rtx
, offset
= var_offset
;
3883 else if (x
== virtual_stack_dynamic_rtx
)
3884 new = stack_pointer_rtx
, offset
= dynamic_offset
;
3885 else if (x
== virtual_outgoing_args_rtx
)
3886 new = stack_pointer_rtx
, offset
= out_arg_offset
;
3887 else if (x
== virtual_cfa_rtx
)
3888 new = arg_pointer_rtx
, offset
= cfa_offset
;
3892 temp
= plus_constant (new, offset
);
3893 if (!validate_change (object
, loc
, temp
, 0))
3899 temp
= force_operand (temp
, NULL_RTX
);
3903 emit_insns_before (seq
, object
);
3904 if (! validate_change (object
, loc
, temp
, 0)
3905 && ! validate_replace_rtx (x
, temp
, object
))
3913 if (GET_CODE (XEXP (x
, 0)) == REG
)
3916 else if (GET_CODE (XEXP (x
, 0)) == MEM
)
3918 /* If we have a (addressof (mem ..)), do any instantiation inside
3919 since we know we'll be making the inside valid when we finally
3920 remove the ADDRESSOF. */
3921 instantiate_virtual_regs_1 (&XEXP (XEXP (x
, 0), 0), NULL_RTX
, 0);
3930 /* Scan all subexpressions. */
3931 fmt
= GET_RTX_FORMAT (code
);
3932 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
3935 if (!instantiate_virtual_regs_1 (&XEXP (x
, i
), object
, extra_insns
))
3938 else if (*fmt
== 'E')
3939 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
3940 if (! instantiate_virtual_regs_1 (&XVECEXP (x
, i
, j
), object
,
3947 /* Optimization: assuming this function does not receive nonlocal gotos,
3948 delete the handlers for such, as well as the insns to establish
3949 and disestablish them. */
3955 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
3957 /* Delete the handler by turning off the flag that would
3958 prevent jump_optimize from deleting it.
3959 Also permit deletion of the nonlocal labels themselves
3960 if nothing local refers to them. */
3961 if (GET_CODE (insn
) == CODE_LABEL
)
3965 LABEL_PRESERVE_P (insn
) = 0;
3967 /* Remove it from the nonlocal_label list, to avoid confusing
3969 for (t
= nonlocal_labels
, last_t
= 0; t
;
3970 last_t
= t
, t
= TREE_CHAIN (t
))
3971 if (DECL_RTL (TREE_VALUE (t
)) == insn
)
3976 nonlocal_labels
= TREE_CHAIN (nonlocal_labels
);
3978 TREE_CHAIN (last_t
) = TREE_CHAIN (t
);
3981 if (GET_CODE (insn
) == INSN
)
3985 for (t
= nonlocal_goto_handler_slots
; t
!= 0; t
= XEXP (t
, 1))
3986 if (reg_mentioned_p (t
, PATTERN (insn
)))
3992 || (nonlocal_goto_stack_level
!= 0
3993 && reg_mentioned_p (nonlocal_goto_stack_level
,
4003 return max_parm_reg
;
4006 /* Return the first insn following those generated by `assign_parms'. */
4009 get_first_nonparm_insn ()
4012 return NEXT_INSN (last_parm_insn
);
4013 return get_insns ();
4016 /* Return the first NOTE_INSN_BLOCK_BEG note in the function.
4017 Crash if there is none. */
4020 get_first_block_beg ()
4022 register rtx searcher
;
4023 register rtx insn
= get_first_nonparm_insn ();
4025 for (searcher
= insn
; searcher
; searcher
= NEXT_INSN (searcher
))
4026 if (GET_CODE (searcher
) == NOTE
4027 && NOTE_LINE_NUMBER (searcher
) == NOTE_INSN_BLOCK_BEG
)
4030 abort (); /* Invalid call to this function. (See comments above.) */
4034 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4035 This means a type for which function calls must pass an address to the
4036 function or get an address back from the function.
4037 EXP may be a type node or an expression (whose type is tested). */
4040 aggregate_value_p (exp
)
4043 int i
, regno
, nregs
;
4046 tree type
= (TYPE_P (exp
)) ? exp
: TREE_TYPE (exp
);
4048 if (TREE_CODE (type
) == VOID_TYPE
)
4050 if (RETURN_IN_MEMORY (type
))
4052 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4053 and thus can't be returned in registers. */
4054 if (TREE_ADDRESSABLE (type
))
4056 if (flag_pcc_struct_return
&& AGGREGATE_TYPE_P (type
))
4058 /* Make sure we have suitable call-clobbered regs to return
4059 the value in; if not, we must return it in memory. */
4060 reg
= hard_function_value (type
, 0, 0);
4062 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4064 if (GET_CODE (reg
) != REG
)
4067 regno
= REGNO (reg
);
4068 nregs
= HARD_REGNO_NREGS (regno
, TYPE_MODE (type
));
4069 for (i
= 0; i
< nregs
; i
++)
4070 if (! call_used_regs
[regno
+ i
])
4075 /* Assign RTL expressions to the function's parameters.
4076 This may involve copying them into registers and using
4077 those registers as the RTL for them. */
4080 assign_parms (fndecl
)
4084 register rtx entry_parm
= 0;
4085 register rtx stack_parm
= 0;
4086 CUMULATIVE_ARGS args_so_far
;
4087 enum machine_mode promoted_mode
, passed_mode
;
4088 enum machine_mode nominal_mode
, promoted_nominal_mode
;
4090 /* Total space needed so far for args on the stack,
4091 given as a constant and a tree-expression. */
4092 struct args_size stack_args_size
;
4093 tree fntype
= TREE_TYPE (fndecl
);
4094 tree fnargs
= DECL_ARGUMENTS (fndecl
);
4095 /* This is used for the arg pointer when referring to stack args. */
4096 rtx internal_arg_pointer
;
4097 /* This is a dummy PARM_DECL that we used for the function result if
4098 the function returns a structure. */
4099 tree function_result_decl
= 0;
4100 #ifdef SETUP_INCOMING_VARARGS
4101 int varargs_setup
= 0;
4103 rtx conversion_insns
= 0;
4104 struct args_size alignment_pad
;
4106 /* Nonzero if the last arg is named `__builtin_va_alist',
4107 which is used on some machines for old-fashioned non-ANSI varargs.h;
4108 this should be stuck onto the stack as if it had arrived there. */
4110 = (current_function_varargs
4112 && (parm
= tree_last (fnargs
)) != 0
4114 && (! strcmp (IDENTIFIER_POINTER (DECL_NAME (parm
)),
4115 "__builtin_va_alist")));
4117 /* Nonzero if function takes extra anonymous args.
4118 This means the last named arg must be on the stack
4119 right before the anonymous ones. */
4121 = (TYPE_ARG_TYPES (fntype
) != 0
4122 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype
)))
4123 != void_type_node
));
4125 current_function_stdarg
= stdarg
;
4127 /* If the reg that the virtual arg pointer will be translated into is
4128 not a fixed reg or is the stack pointer, make a copy of the virtual
4129 arg pointer, and address parms via the copy. The frame pointer is
4130 considered fixed even though it is not marked as such.
4132 The second time through, simply use ap to avoid generating rtx. */
4134 if ((ARG_POINTER_REGNUM
== STACK_POINTER_REGNUM
4135 || ! (fixed_regs
[ARG_POINTER_REGNUM
]
4136 || ARG_POINTER_REGNUM
== FRAME_POINTER_REGNUM
)))
4137 internal_arg_pointer
= copy_to_reg (virtual_incoming_args_rtx
);
4139 internal_arg_pointer
= virtual_incoming_args_rtx
;
4140 current_function_internal_arg_pointer
= internal_arg_pointer
;
4142 stack_args_size
.constant
= 0;
4143 stack_args_size
.var
= 0;
4145 /* If struct value address is treated as the first argument, make it so. */
4146 if (aggregate_value_p (DECL_RESULT (fndecl
))
4147 && ! current_function_returns_pcc_struct
4148 && struct_value_incoming_rtx
== 0)
4150 tree type
= build_pointer_type (TREE_TYPE (fntype
));
4152 function_result_decl
= build_decl (PARM_DECL
, NULL_TREE
, type
);
4154 DECL_ARG_TYPE (function_result_decl
) = type
;
4155 TREE_CHAIN (function_result_decl
) = fnargs
;
4156 fnargs
= function_result_decl
;
4159 max_parm_reg
= LAST_VIRTUAL_REGISTER
+ 1;
4160 parm_reg_stack_loc
= (rtx
*) xcalloc (max_parm_reg
, sizeof (rtx
));
4162 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4163 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far
, fntype
, NULL_RTX
);
4165 INIT_CUMULATIVE_ARGS (args_so_far
, fntype
, NULL_RTX
, 0);
4168 /* We haven't yet found an argument that we must push and pretend the
4170 current_function_pretend_args_size
= 0;
4172 for (parm
= fnargs
; parm
; parm
= TREE_CHAIN (parm
))
4174 int aggregate
= AGGREGATE_TYPE_P (TREE_TYPE (parm
));
4175 struct args_size stack_offset
;
4176 struct args_size arg_size
;
4177 int passed_pointer
= 0;
4178 int did_conversion
= 0;
4179 tree passed_type
= DECL_ARG_TYPE (parm
);
4180 tree nominal_type
= TREE_TYPE (parm
);
4183 /* Set LAST_NAMED if this is last named arg before some
4185 int last_named
= ((TREE_CHAIN (parm
) == 0
4186 || DECL_NAME (TREE_CHAIN (parm
)) == 0)
4187 && (stdarg
|| current_function_varargs
));
4188 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4189 most machines, if this is a varargs/stdarg function, then we treat
4190 the last named arg as if it were anonymous too. */
4191 int named_arg
= STRICT_ARGUMENT_NAMING
? 1 : ! last_named
;
4193 if (TREE_TYPE (parm
) == error_mark_node
4194 /* This can happen after weird syntax errors
4195 or if an enum type is defined among the parms. */
4196 || TREE_CODE (parm
) != PARM_DECL
4197 || passed_type
== NULL
)
4199 DECL_INCOMING_RTL (parm
) = DECL_RTL (parm
)
4200 = gen_rtx_MEM (BLKmode
, const0_rtx
);
4201 TREE_USED (parm
) = 1;
4205 /* For varargs.h function, save info about regs and stack space
4206 used by the individual args, not including the va_alist arg. */
4207 if (hide_last_arg
&& last_named
)
4208 current_function_args_info
= args_so_far
;
4210 /* Find mode of arg as it is passed, and mode of arg
4211 as it should be during execution of this function. */
4212 passed_mode
= TYPE_MODE (passed_type
);
4213 nominal_mode
= TYPE_MODE (nominal_type
);
4215 /* If the parm's mode is VOID, its value doesn't matter,
4216 and avoid the usual things like emit_move_insn that could crash. */
4217 if (nominal_mode
== VOIDmode
)
4219 DECL_INCOMING_RTL (parm
) = DECL_RTL (parm
) = const0_rtx
;
4223 /* If the parm is to be passed as a transparent union, use the
4224 type of the first field for the tests below. We have already
4225 verified that the modes are the same. */
4226 if (DECL_TRANSPARENT_UNION (parm
)
4227 || TYPE_TRANSPARENT_UNION (passed_type
))
4228 passed_type
= TREE_TYPE (TYPE_FIELDS (passed_type
));
4230 /* See if this arg was passed by invisible reference. It is if
4231 it is an object whose size depends on the contents of the
4232 object itself or if the machine requires these objects be passed
4235 if ((TREE_CODE (TYPE_SIZE (passed_type
)) != INTEGER_CST
4236 && contains_placeholder_p (TYPE_SIZE (passed_type
)))
4237 || TREE_ADDRESSABLE (passed_type
)
4238 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4239 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far
, passed_mode
,
4240 passed_type
, named_arg
)
4244 passed_type
= nominal_type
= build_pointer_type (passed_type
);
4246 passed_mode
= nominal_mode
= Pmode
;
4249 promoted_mode
= passed_mode
;
4251 #ifdef PROMOTE_FUNCTION_ARGS
4252 /* Compute the mode in which the arg is actually extended to. */
4253 unsignedp
= TREE_UNSIGNED (passed_type
);
4254 promoted_mode
= promote_mode (passed_type
, promoted_mode
, &unsignedp
, 1);
4257 /* Let machine desc say which reg (if any) the parm arrives in.
4258 0 means it arrives on the stack. */
4259 #ifdef FUNCTION_INCOMING_ARG
4260 entry_parm
= FUNCTION_INCOMING_ARG (args_so_far
, promoted_mode
,
4261 passed_type
, named_arg
);
4263 entry_parm
= FUNCTION_ARG (args_so_far
, promoted_mode
,
4264 passed_type
, named_arg
);
4267 if (entry_parm
== 0)
4268 promoted_mode
= passed_mode
;
4270 #ifdef SETUP_INCOMING_VARARGS
4271 /* If this is the last named parameter, do any required setup for
4272 varargs or stdargs. We need to know about the case of this being an
4273 addressable type, in which case we skip the registers it
4274 would have arrived in.
4276 For stdargs, LAST_NAMED will be set for two parameters, the one that
4277 is actually the last named, and the dummy parameter. We only
4278 want to do this action once.
4280 Also, indicate when RTL generation is to be suppressed. */
4281 if (last_named
&& !varargs_setup
)
4283 SETUP_INCOMING_VARARGS (args_so_far
, promoted_mode
, passed_type
,
4284 current_function_pretend_args_size
, 0);
4289 /* Determine parm's home in the stack,
4290 in case it arrives in the stack or we should pretend it did.
4292 Compute the stack position and rtx where the argument arrives
4295 There is one complexity here: If this was a parameter that would
4296 have been passed in registers, but wasn't only because it is
4297 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4298 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4299 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4300 0 as it was the previous time. */
4302 pretend_named
= named_arg
|| PRETEND_OUTGOING_VARARGS_NAMED
;
4303 locate_and_pad_parm (promoted_mode
, passed_type
,
4304 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4307 #ifdef FUNCTION_INCOMING_ARG
4308 FUNCTION_INCOMING_ARG (args_so_far
, promoted_mode
,
4310 pretend_named
) != 0,
4312 FUNCTION_ARG (args_so_far
, promoted_mode
,
4314 pretend_named
) != 0,
4317 fndecl
, &stack_args_size
, &stack_offset
, &arg_size
,
4321 rtx offset_rtx
= ARGS_SIZE_RTX (stack_offset
);
4323 if (offset_rtx
== const0_rtx
)
4324 stack_parm
= gen_rtx_MEM (promoted_mode
, internal_arg_pointer
);
4326 stack_parm
= gen_rtx_MEM (promoted_mode
,
4327 gen_rtx_PLUS (Pmode
,
4328 internal_arg_pointer
,
4331 /* If this is a memory ref that contains aggregate components,
4332 mark it as such for cse and loop optimize. Likewise if it
4334 MEM_SET_IN_STRUCT_P (stack_parm
, aggregate
);
4335 RTX_UNCHANGING_P (stack_parm
) = TREE_READONLY (parm
);
4336 MEM_ALIAS_SET (stack_parm
) = get_alias_set (parm
);
4339 /* If this parameter was passed both in registers and in the stack,
4340 use the copy on the stack. */
4341 if (MUST_PASS_IN_STACK (promoted_mode
, passed_type
))
4344 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4345 /* If this parm was passed part in regs and part in memory,
4346 pretend it arrived entirely in memory
4347 by pushing the register-part onto the stack.
4349 In the special case of a DImode or DFmode that is split,
4350 we could put it together in a pseudoreg directly,
4351 but for now that's not worth bothering with. */
4355 int nregs
= FUNCTION_ARG_PARTIAL_NREGS (args_so_far
, promoted_mode
,
4356 passed_type
, named_arg
);
4360 current_function_pretend_args_size
4361 = (((nregs
* UNITS_PER_WORD
) + (PARM_BOUNDARY
/ BITS_PER_UNIT
) - 1)
4362 / (PARM_BOUNDARY
/ BITS_PER_UNIT
)
4363 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
4365 /* Handle calls that pass values in multiple non-contiguous
4366 locations. The Irix 6 ABI has examples of this. */
4367 if (GET_CODE (entry_parm
) == PARALLEL
)
4368 emit_group_store (validize_mem (stack_parm
), entry_parm
,
4369 int_size_in_bytes (TREE_TYPE (parm
)),
4370 TYPE_ALIGN (TREE_TYPE (parm
)));
4373 move_block_from_reg (REGNO (entry_parm
),
4374 validize_mem (stack_parm
), nregs
,
4375 int_size_in_bytes (TREE_TYPE (parm
)));
4377 entry_parm
= stack_parm
;
4382 /* If we didn't decide this parm came in a register,
4383 by default it came on the stack. */
4384 if (entry_parm
== 0)
4385 entry_parm
= stack_parm
;
4387 /* Record permanently how this parm was passed. */
4388 DECL_INCOMING_RTL (parm
) = entry_parm
;
4390 /* If there is actually space on the stack for this parm,
4391 count it in stack_args_size; otherwise set stack_parm to 0
4392 to indicate there is no preallocated stack slot for the parm. */
4394 if (entry_parm
== stack_parm
4395 || (GET_CODE (entry_parm
) == PARALLEL
4396 && XEXP (XVECEXP (entry_parm
, 0, 0), 0) == NULL_RTX
)
4397 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4398 /* On some machines, even if a parm value arrives in a register
4399 there is still an (uninitialized) stack slot allocated for it.
4401 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4402 whether this parameter already has a stack slot allocated,
4403 because an arg block exists only if current_function_args_size
4404 is larger than some threshold, and we haven't calculated that
4405 yet. So, for now, we just assume that stack slots never exist
4407 || REG_PARM_STACK_SPACE (fndecl
) > 0
4411 stack_args_size
.constant
+= arg_size
.constant
;
4413 ADD_PARM_SIZE (stack_args_size
, arg_size
.var
);
4416 /* No stack slot was pushed for this parm. */
4419 /* Update info on where next arg arrives in registers. */
4421 FUNCTION_ARG_ADVANCE (args_so_far
, promoted_mode
,
4422 passed_type
, named_arg
);
4424 /* If we can't trust the parm stack slot to be aligned enough
4425 for its ultimate type, don't use that slot after entry.
4426 We'll make another stack slot, if we need one. */
4428 unsigned int thisparm_boundary
4429 = FUNCTION_ARG_BOUNDARY (promoted_mode
, passed_type
);
4431 if (GET_MODE_ALIGNMENT (nominal_mode
) > thisparm_boundary
)
4435 /* If parm was passed in memory, and we need to convert it on entry,
4436 don't store it back in that same slot. */
4438 && nominal_mode
!= BLKmode
&& nominal_mode
!= passed_mode
)
4442 /* Now adjust STACK_PARM to the mode and precise location
4443 where this parameter should live during execution,
4444 if we discover that it must live in the stack during execution.
4445 To make debuggers happier on big-endian machines, we store
4446 the value in the last bytes of the space available. */
4448 if (nominal_mode
!= BLKmode
&& nominal_mode
!= passed_mode
4453 if (BYTES_BIG_ENDIAN
4454 && GET_MODE_SIZE (nominal_mode
) < UNITS_PER_WORD
)
4455 stack_offset
.constant
+= (GET_MODE_SIZE (passed_mode
)
4456 - GET_MODE_SIZE (nominal_mode
));
4458 offset_rtx
= ARGS_SIZE_RTX (stack_offset
);
4459 if (offset_rtx
== const0_rtx
)
4460 stack_parm
= gen_rtx_MEM (nominal_mode
, internal_arg_pointer
);
4462 stack_parm
= gen_rtx_MEM (nominal_mode
,
4463 gen_rtx_PLUS (Pmode
,
4464 internal_arg_pointer
,
4467 /* If this is a memory ref that contains aggregate components,
4468 mark it as such for cse and loop optimize. */
4469 MEM_SET_IN_STRUCT_P (stack_parm
, aggregate
);
4473 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4474 in the mode in which it arrives.
4475 STACK_PARM is an RTX for a stack slot where the parameter can live
4476 during the function (in case we want to put it there).
4477 STACK_PARM is 0 if no stack slot was pushed for it.
4479 Now output code if necessary to convert ENTRY_PARM to
4480 the type in which this function declares it,
4481 and store that result in an appropriate place,
4482 which may be a pseudo reg, may be STACK_PARM,
4483 or may be a local stack slot if STACK_PARM is 0.
4485 Set DECL_RTL to that place. */
4487 if (nominal_mode
== BLKmode
|| GET_CODE (entry_parm
) == PARALLEL
)
4489 /* If a BLKmode arrives in registers, copy it to a stack slot.
4490 Handle calls that pass values in multiple non-contiguous
4491 locations. The Irix 6 ABI has examples of this. */
4492 if (GET_CODE (entry_parm
) == REG
4493 || GET_CODE (entry_parm
) == PARALLEL
)
4496 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm
)),
4499 /* Note that we will be storing an integral number of words.
4500 So we have to be careful to ensure that we allocate an
4501 integral number of words. We do this below in the
4502 assign_stack_local if space was not allocated in the argument
4503 list. If it was, this will not work if PARM_BOUNDARY is not
4504 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4505 if it becomes a problem. */
4507 if (stack_parm
== 0)
4510 = assign_stack_local (GET_MODE (entry_parm
),
4513 /* If this is a memory ref that contains aggregate
4514 components, mark it as such for cse and loop optimize. */
4515 MEM_SET_IN_STRUCT_P (stack_parm
, aggregate
);
4518 else if (PARM_BOUNDARY
% BITS_PER_WORD
!= 0)
4521 if (TREE_READONLY (parm
))
4522 RTX_UNCHANGING_P (stack_parm
) = 1;
4524 /* Handle calls that pass values in multiple non-contiguous
4525 locations. The Irix 6 ABI has examples of this. */
4526 if (GET_CODE (entry_parm
) == PARALLEL
)
4527 emit_group_store (validize_mem (stack_parm
), entry_parm
,
4528 int_size_in_bytes (TREE_TYPE (parm
)),
4529 TYPE_ALIGN (TREE_TYPE (parm
)));
4531 move_block_from_reg (REGNO (entry_parm
),
4532 validize_mem (stack_parm
),
4533 size_stored
/ UNITS_PER_WORD
,
4534 int_size_in_bytes (TREE_TYPE (parm
)));
4536 DECL_RTL (parm
) = stack_parm
;
4538 else if (! ((! optimize
4539 && ! DECL_REGISTER (parm
)
4540 && ! DECL_INLINE (fndecl
))
4541 /* layout_decl may set this. */
4542 || TREE_ADDRESSABLE (parm
)
4543 || TREE_SIDE_EFFECTS (parm
)
4544 /* If -ffloat-store specified, don't put explicit
4545 float variables into registers. */
4546 || (flag_float_store
4547 && TREE_CODE (TREE_TYPE (parm
)) == REAL_TYPE
))
4548 /* Always assign pseudo to structure return or item passed
4549 by invisible reference. */
4550 || passed_pointer
|| parm
== function_result_decl
)
4552 /* Store the parm in a pseudoregister during the function, but we
4553 may need to do it in a wider mode. */
4555 register rtx parmreg
;
4556 unsigned int regno
, regnoi
= 0, regnor
= 0;
4558 unsignedp
= TREE_UNSIGNED (TREE_TYPE (parm
));
4560 promoted_nominal_mode
4561 = promote_mode (TREE_TYPE (parm
), nominal_mode
, &unsignedp
, 0);
4563 parmreg
= gen_reg_rtx (promoted_nominal_mode
);
4564 mark_user_reg (parmreg
);
4566 /* If this was an item that we received a pointer to, set DECL_RTL
4571 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type
)), parmreg
);
4572 MEM_SET_IN_STRUCT_P (DECL_RTL (parm
), aggregate
);
4575 DECL_RTL (parm
) = parmreg
;
4577 /* Copy the value into the register. */
4578 if (nominal_mode
!= passed_mode
4579 || promoted_nominal_mode
!= promoted_mode
)
4582 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4583 mode, by the caller. We now have to convert it to
4584 NOMINAL_MODE, if different. However, PARMREG may be in
4585 a different mode than NOMINAL_MODE if it is being stored
4588 If ENTRY_PARM is a hard register, it might be in a register
4589 not valid for operating in its mode (e.g., an odd-numbered
4590 register for a DFmode). In that case, moves are the only
4591 thing valid, so we can't do a convert from there. This
4592 occurs when the calling sequence allow such misaligned
4595 In addition, the conversion may involve a call, which could
4596 clobber parameters which haven't been copied to pseudo
4597 registers yet. Therefore, we must first copy the parm to
4598 a pseudo reg here, and save the conversion until after all
4599 parameters have been moved. */
4601 rtx tempreg
= gen_reg_rtx (GET_MODE (entry_parm
));
4603 emit_move_insn (tempreg
, validize_mem (entry_parm
));
4605 push_to_sequence (conversion_insns
);
4606 tempreg
= convert_to_mode (nominal_mode
, tempreg
, unsignedp
);
4608 /* TREE_USED gets set erroneously during expand_assignment. */
4609 save_tree_used
= TREE_USED (parm
);
4610 expand_assignment (parm
,
4611 make_tree (nominal_type
, tempreg
), 0, 0);
4612 TREE_USED (parm
) = save_tree_used
;
4613 conversion_insns
= get_insns ();
4618 emit_move_insn (parmreg
, validize_mem (entry_parm
));
4620 /* If we were passed a pointer but the actual value
4621 can safely live in a register, put it in one. */
4622 if (passed_pointer
&& TYPE_MODE (TREE_TYPE (parm
)) != BLKmode
4624 && ! DECL_REGISTER (parm
)
4625 && ! DECL_INLINE (fndecl
))
4626 /* layout_decl may set this. */
4627 || TREE_ADDRESSABLE (parm
)
4628 || TREE_SIDE_EFFECTS (parm
)
4629 /* If -ffloat-store specified, don't put explicit
4630 float variables into registers. */
4631 || (flag_float_store
4632 && TREE_CODE (TREE_TYPE (parm
)) == REAL_TYPE
)))
4634 /* We can't use nominal_mode, because it will have been set to
4635 Pmode above. We must use the actual mode of the parm. */
4636 parmreg
= gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm
)));
4637 mark_user_reg (parmreg
);
4638 emit_move_insn (parmreg
, DECL_RTL (parm
));
4639 DECL_RTL (parm
) = parmreg
;
4640 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4644 #ifdef FUNCTION_ARG_CALLEE_COPIES
4645 /* If we are passed an arg by reference and it is our responsibility
4646 to make a copy, do it now.
4647 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4648 original argument, so we must recreate them in the call to
4649 FUNCTION_ARG_CALLEE_COPIES. */
4650 /* ??? Later add code to handle the case that if the argument isn't
4651 modified, don't do the copy. */
4653 else if (passed_pointer
4654 && FUNCTION_ARG_CALLEE_COPIES (args_so_far
,
4655 TYPE_MODE (DECL_ARG_TYPE (parm
)),
4656 DECL_ARG_TYPE (parm
),
4658 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm
)))
4661 tree type
= DECL_ARG_TYPE (parm
);
4663 /* This sequence may involve a library call perhaps clobbering
4664 registers that haven't been copied to pseudos yet. */
4666 push_to_sequence (conversion_insns
);
4668 if (!COMPLETE_TYPE_P (type
)
4669 || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
4670 /* This is a variable sized object. */
4671 copy
= gen_rtx_MEM (BLKmode
,
4672 allocate_dynamic_stack_space
4673 (expr_size (parm
), NULL_RTX
,
4674 TYPE_ALIGN (type
)));
4676 copy
= assign_stack_temp (TYPE_MODE (type
),
4677 int_size_in_bytes (type
), 1);
4678 MEM_SET_IN_STRUCT_P (copy
, AGGREGATE_TYPE_P (type
));
4679 RTX_UNCHANGING_P (copy
) = TREE_READONLY (parm
);
4681 store_expr (parm
, copy
, 0);
4682 emit_move_insn (parmreg
, XEXP (copy
, 0));
4683 if (current_function_check_memory_usage
)
4684 emit_library_call (chkr_set_right_libfunc
, 1, VOIDmode
, 3,
4685 XEXP (copy
, 0), Pmode
,
4686 GEN_INT (int_size_in_bytes (type
)),
4687 TYPE_MODE (sizetype
),
4688 GEN_INT (MEMORY_USE_RW
),
4689 TYPE_MODE (integer_type_node
));
4690 conversion_insns
= get_insns ();
4694 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4696 /* In any case, record the parm's desired stack location
4697 in case we later discover it must live in the stack.
4699 If it is a COMPLEX value, store the stack location for both
4702 if (GET_CODE (parmreg
) == CONCAT
)
4703 regno
= MAX (REGNO (XEXP (parmreg
, 0)), REGNO (XEXP (parmreg
, 1)));
4705 regno
= REGNO (parmreg
);
4707 if (regno
>= max_parm_reg
)
4710 int old_max_parm_reg
= max_parm_reg
;
4712 /* It's slow to expand this one register at a time,
4713 but it's also rare and we need max_parm_reg to be
4714 precisely correct. */
4715 max_parm_reg
= regno
+ 1;
4716 new = (rtx
*) xrealloc (parm_reg_stack_loc
,
4717 max_parm_reg
* sizeof (rtx
));
4718 bzero ((char *) (new + old_max_parm_reg
),
4719 (max_parm_reg
- old_max_parm_reg
) * sizeof (rtx
));
4720 parm_reg_stack_loc
= new;
4723 if (GET_CODE (parmreg
) == CONCAT
)
4725 enum machine_mode submode
= GET_MODE (XEXP (parmreg
, 0));
4727 regnor
= REGNO (gen_realpart (submode
, parmreg
));
4728 regnoi
= REGNO (gen_imagpart (submode
, parmreg
));
4730 if (stack_parm
!= 0)
4732 parm_reg_stack_loc
[regnor
]
4733 = gen_realpart (submode
, stack_parm
);
4734 parm_reg_stack_loc
[regnoi
]
4735 = gen_imagpart (submode
, stack_parm
);
4739 parm_reg_stack_loc
[regnor
] = 0;
4740 parm_reg_stack_loc
[regnoi
] = 0;
4744 parm_reg_stack_loc
[REGNO (parmreg
)] = stack_parm
;
4746 /* Mark the register as eliminable if we did no conversion
4747 and it was copied from memory at a fixed offset,
4748 and the arg pointer was not copied to a pseudo-reg.
4749 If the arg pointer is a pseudo reg or the offset formed
4750 an invalid address, such memory-equivalences
4751 as we make here would screw up life analysis for it. */
4752 if (nominal_mode
== passed_mode
4755 && GET_CODE (stack_parm
) == MEM
4756 && stack_offset
.var
== 0
4757 && reg_mentioned_p (virtual_incoming_args_rtx
,
4758 XEXP (stack_parm
, 0)))
4760 rtx linsn
= get_last_insn ();
4763 /* Mark complex types separately. */
4764 if (GET_CODE (parmreg
) == CONCAT
)
4765 /* Scan backwards for the set of the real and
4767 for (sinsn
= linsn
; sinsn
!= 0;
4768 sinsn
= prev_nonnote_insn (sinsn
))
4770 set
= single_set (sinsn
);
4772 && SET_DEST (set
) == regno_reg_rtx
[regnoi
])
4774 = gen_rtx_EXPR_LIST (REG_EQUIV
,
4775 parm_reg_stack_loc
[regnoi
],
4778 && SET_DEST (set
) == regno_reg_rtx
[regnor
])
4780 = gen_rtx_EXPR_LIST (REG_EQUIV
,
4781 parm_reg_stack_loc
[regnor
],
4784 else if ((set
= single_set (linsn
)) != 0
4785 && SET_DEST (set
) == parmreg
)
4787 = gen_rtx_EXPR_LIST (REG_EQUIV
,
4788 stack_parm
, REG_NOTES (linsn
));
4791 /* For pointer data type, suggest pointer register. */
4792 if (POINTER_TYPE_P (TREE_TYPE (parm
)))
4793 mark_reg_pointer (parmreg
,
4794 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
4799 /* Value must be stored in the stack slot STACK_PARM
4800 during function execution. */
4802 if (promoted_mode
!= nominal_mode
)
4804 /* Conversion is required. */
4805 rtx tempreg
= gen_reg_rtx (GET_MODE (entry_parm
));
4807 emit_move_insn (tempreg
, validize_mem (entry_parm
));
4809 push_to_sequence (conversion_insns
);
4810 entry_parm
= convert_to_mode (nominal_mode
, tempreg
,
4811 TREE_UNSIGNED (TREE_TYPE (parm
)));
4814 /* ??? This may need a big-endian conversion on sparc64. */
4815 stack_parm
= change_address (stack_parm
, nominal_mode
,
4818 conversion_insns
= get_insns ();
4823 if (entry_parm
!= stack_parm
)
4825 if (stack_parm
== 0)
4828 = assign_stack_local (GET_MODE (entry_parm
),
4829 GET_MODE_SIZE (GET_MODE (entry_parm
)), 0);
4830 /* If this is a memory ref that contains aggregate components,
4831 mark it as such for cse and loop optimize. */
4832 MEM_SET_IN_STRUCT_P (stack_parm
, aggregate
);
4835 if (promoted_mode
!= nominal_mode
)
4837 push_to_sequence (conversion_insns
);
4838 emit_move_insn (validize_mem (stack_parm
),
4839 validize_mem (entry_parm
));
4840 conversion_insns
= get_insns ();
4844 emit_move_insn (validize_mem (stack_parm
),
4845 validize_mem (entry_parm
));
4847 if (current_function_check_memory_usage
)
4849 push_to_sequence (conversion_insns
);
4850 emit_library_call (chkr_set_right_libfunc
, 1, VOIDmode
, 3,
4851 XEXP (stack_parm
, 0), Pmode
,
4852 GEN_INT (GET_MODE_SIZE (GET_MODE
4854 TYPE_MODE (sizetype
),
4855 GEN_INT (MEMORY_USE_RW
),
4856 TYPE_MODE (integer_type_node
));
4858 conversion_insns
= get_insns ();
4861 DECL_RTL (parm
) = stack_parm
;
4864 /* If this "parameter" was the place where we are receiving the
4865 function's incoming structure pointer, set up the result. */
4866 if (parm
== function_result_decl
)
4868 tree result
= DECL_RESULT (fndecl
);
4869 tree restype
= TREE_TYPE (result
);
4872 = gen_rtx_MEM (DECL_MODE (result
), DECL_RTL (parm
));
4874 MEM_SET_IN_STRUCT_P (DECL_RTL (result
),
4875 AGGREGATE_TYPE_P (restype
));
4878 if (TREE_THIS_VOLATILE (parm
))
4879 MEM_VOLATILE_P (DECL_RTL (parm
)) = 1;
4880 if (TREE_READONLY (parm
))
4881 RTX_UNCHANGING_P (DECL_RTL (parm
)) = 1;
4884 /* Output all parameter conversion instructions (possibly including calls)
4885 now that all parameters have been copied out of hard registers. */
4886 emit_insns (conversion_insns
);
4888 last_parm_insn
= get_last_insn ();
4890 current_function_args_size
= stack_args_size
.constant
;
4892 /* Adjust function incoming argument size for alignment and
4895 #ifdef REG_PARM_STACK_SPACE
4896 #ifndef MAYBE_REG_PARM_STACK_SPACE
4897 current_function_args_size
= MAX (current_function_args_size
,
4898 REG_PARM_STACK_SPACE (fndecl
));
4902 #ifdef STACK_BOUNDARY
4903 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
4905 current_function_args_size
4906 = ((current_function_args_size
+ STACK_BYTES
- 1)
4907 / STACK_BYTES
) * STACK_BYTES
;
4910 #ifdef ARGS_GROW_DOWNWARD
4911 current_function_arg_offset_rtx
4912 = (stack_args_size
.var
== 0 ? GEN_INT (-stack_args_size
.constant
)
4913 : expand_expr (size_diffop (stack_args_size
.var
,
4914 size_int (-stack_args_size
.constant
)),
4915 NULL_RTX
, VOIDmode
, EXPAND_MEMORY_USE_BAD
));
4917 current_function_arg_offset_rtx
= ARGS_SIZE_RTX (stack_args_size
);
4920 /* See how many bytes, if any, of its args a function should try to pop
4923 current_function_pops_args
= RETURN_POPS_ARGS (fndecl
, TREE_TYPE (fndecl
),
4924 current_function_args_size
);
4926 /* For stdarg.h function, save info about
4927 regs and stack space used by the named args. */
4930 current_function_args_info
= args_so_far
;
4932 /* Set the rtx used for the function return value. Put this in its
4933 own variable so any optimizers that need this information don't have
4934 to include tree.h. Do this here so it gets done when an inlined
4935 function gets output. */
4937 current_function_return_rtx
= DECL_RTL (DECL_RESULT (fndecl
));
4940 /* Indicate whether REGNO is an incoming argument to the current function
4941 that was promoted to a wider mode. If so, return the RTX for the
4942 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
4943 that REGNO is promoted from and whether the promotion was signed or
4946 #ifdef PROMOTE_FUNCTION_ARGS
4949 promoted_input_arg (regno
, pmode
, punsignedp
)
4951 enum machine_mode
*pmode
;
4956 for (arg
= DECL_ARGUMENTS (current_function_decl
); arg
;
4957 arg
= TREE_CHAIN (arg
))
4958 if (GET_CODE (DECL_INCOMING_RTL (arg
)) == REG
4959 && REGNO (DECL_INCOMING_RTL (arg
)) == regno
4960 && TYPE_MODE (DECL_ARG_TYPE (arg
)) == TYPE_MODE (TREE_TYPE (arg
)))
4962 enum machine_mode mode
= TYPE_MODE (TREE_TYPE (arg
));
4963 int unsignedp
= TREE_UNSIGNED (TREE_TYPE (arg
));
4965 mode
= promote_mode (TREE_TYPE (arg
), mode
, &unsignedp
, 1);
4966 if (mode
== GET_MODE (DECL_INCOMING_RTL (arg
))
4967 && mode
!= DECL_MODE (arg
))
4969 *pmode
= DECL_MODE (arg
);
4970 *punsignedp
= unsignedp
;
4971 return DECL_INCOMING_RTL (arg
);
4980 /* Compute the size and offset from the start of the stacked arguments for a
4981 parm passed in mode PASSED_MODE and with type TYPE.
4983 INITIAL_OFFSET_PTR points to the current offset into the stacked
4986 The starting offset and size for this parm are returned in *OFFSET_PTR
4987 and *ARG_SIZE_PTR, respectively.
4989 IN_REGS is non-zero if the argument will be passed in registers. It will
4990 never be set if REG_PARM_STACK_SPACE is not defined.
4992 FNDECL is the function in which the argument was defined.
4994 There are two types of rounding that are done. The first, controlled by
4995 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
4996 list to be aligned to the specific boundary (in bits). This rounding
4997 affects the initial and starting offsets, but not the argument size.
4999 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5000 optionally rounds the size of the parm to PARM_BOUNDARY. The
5001 initial offset is not affected by this rounding, while the size always
5002 is and the starting offset may be. */
5004 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
5005 initial_offset_ptr is positive because locate_and_pad_parm's
5006 callers pass in the total size of args so far as
5007 initial_offset_ptr. arg_size_ptr is always positive.*/
5010 locate_and_pad_parm (passed_mode
, type
, in_regs
, fndecl
,
5011 initial_offset_ptr
, offset_ptr
, arg_size_ptr
,
5013 enum machine_mode passed_mode
;
5015 int in_regs ATTRIBUTE_UNUSED
;
5016 tree fndecl ATTRIBUTE_UNUSED
;
5017 struct args_size
*initial_offset_ptr
;
5018 struct args_size
*offset_ptr
;
5019 struct args_size
*arg_size_ptr
;
5020 struct args_size
*alignment_pad
;
5024 = type
? size_in_bytes (type
) : size_int (GET_MODE_SIZE (passed_mode
));
5025 enum direction where_pad
= FUNCTION_ARG_PADDING (passed_mode
, type
);
5026 int boundary
= FUNCTION_ARG_BOUNDARY (passed_mode
, type
);
5028 #ifdef REG_PARM_STACK_SPACE
5029 /* If we have found a stack parm before we reach the end of the
5030 area reserved for registers, skip that area. */
5033 int reg_parm_stack_space
= 0;
5035 #ifdef MAYBE_REG_PARM_STACK_SPACE
5036 reg_parm_stack_space
= MAYBE_REG_PARM_STACK_SPACE
;
5038 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
5040 if (reg_parm_stack_space
> 0)
5042 if (initial_offset_ptr
->var
)
5044 initial_offset_ptr
->var
5045 = size_binop (MAX_EXPR
, ARGS_SIZE_TREE (*initial_offset_ptr
),
5046 ssize_int (reg_parm_stack_space
));
5047 initial_offset_ptr
->constant
= 0;
5049 else if (initial_offset_ptr
->constant
< reg_parm_stack_space
)
5050 initial_offset_ptr
->constant
= reg_parm_stack_space
;
5053 #endif /* REG_PARM_STACK_SPACE */
5055 arg_size_ptr
->var
= 0;
5056 arg_size_ptr
->constant
= 0;
5058 #ifdef ARGS_GROW_DOWNWARD
5059 if (initial_offset_ptr
->var
)
5061 offset_ptr
->constant
= 0;
5062 offset_ptr
->var
= size_binop (MINUS_EXPR
, ssize_int (0),
5063 initial_offset_ptr
->var
);
5067 offset_ptr
->constant
= - initial_offset_ptr
->constant
;
5068 offset_ptr
->var
= 0;
5070 if (where_pad
!= none
5071 && (TREE_CODE (sizetree
) != INTEGER_CST
5072 || ((TREE_INT_CST_LOW (sizetree
) * BITS_PER_UNIT
) % PARM_BOUNDARY
)))
5073 sizetree
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
5074 SUB_PARM_SIZE (*offset_ptr
, sizetree
);
5075 if (where_pad
!= downward
)
5076 pad_to_arg_alignment (offset_ptr
, boundary
, alignment_pad
);
5077 if (initial_offset_ptr
->var
)
5078 arg_size_ptr
->var
= size_binop (MINUS_EXPR
,
5079 size_binop (MINUS_EXPR
,
5081 initial_offset_ptr
->var
),
5085 arg_size_ptr
->constant
= (- initial_offset_ptr
->constant
5086 - offset_ptr
->constant
);
5088 #else /* !ARGS_GROW_DOWNWARD */
5089 pad_to_arg_alignment (initial_offset_ptr
, boundary
, alignment_pad
);
5090 *offset_ptr
= *initial_offset_ptr
;
5092 #ifdef PUSH_ROUNDING
5093 if (passed_mode
!= BLKmode
)
5094 sizetree
= size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree
)));
5097 /* Pad_below needs the pre-rounded size to know how much to pad below
5098 so this must be done before rounding up. */
5099 if (where_pad
== downward
5100 /* However, BLKmode args passed in regs have their padding done elsewhere.
5101 The stack slot must be able to hold the entire register. */
5102 && !(in_regs
&& passed_mode
== BLKmode
))
5103 pad_below (offset_ptr
, passed_mode
, sizetree
);
5105 if (where_pad
!= none
5106 && (TREE_CODE (sizetree
) != INTEGER_CST
5107 || ((TREE_INT_CST_LOW (sizetree
) * BITS_PER_UNIT
) % PARM_BOUNDARY
)))
5108 sizetree
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
5110 ADD_PARM_SIZE (*arg_size_ptr
, sizetree
);
5111 #endif /* ARGS_GROW_DOWNWARD */
5114 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5115 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5118 pad_to_arg_alignment (offset_ptr
, boundary
, alignment_pad
)
5119 struct args_size
*offset_ptr
;
5121 struct args_size
*alignment_pad
;
5123 tree save_var
= NULL_TREE
;
5124 HOST_WIDE_INT save_constant
= 0;
5126 int boundary_in_bytes
= boundary
/ BITS_PER_UNIT
;
5128 if (boundary
> PARM_BOUNDARY
&& boundary
> STACK_BOUNDARY
)
5130 save_var
= offset_ptr
->var
;
5131 save_constant
= offset_ptr
->constant
;
5134 alignment_pad
->var
= NULL_TREE
;
5135 alignment_pad
->constant
= 0;
5137 if (boundary
> BITS_PER_UNIT
)
5139 if (offset_ptr
->var
)
5142 #ifdef ARGS_GROW_DOWNWARD
5147 (ARGS_SIZE_TREE (*offset_ptr
),
5148 boundary
/ BITS_PER_UNIT
);
5149 offset_ptr
->constant
= 0; /*?*/
5150 if (boundary
> PARM_BOUNDARY
&& boundary
> STACK_BOUNDARY
)
5151 alignment_pad
->var
= size_binop (MINUS_EXPR
, offset_ptr
->var
,
5156 offset_ptr
->constant
=
5157 #ifdef ARGS_GROW_DOWNWARD
5158 FLOOR_ROUND (offset_ptr
->constant
, boundary_in_bytes
);
5160 CEIL_ROUND (offset_ptr
->constant
, boundary_in_bytes
);
5162 if (boundary
> PARM_BOUNDARY
&& boundary
> STACK_BOUNDARY
)
5163 alignment_pad
->constant
= offset_ptr
->constant
- save_constant
;
5168 #ifndef ARGS_GROW_DOWNWARD
5170 pad_below (offset_ptr
, passed_mode
, sizetree
)
5171 struct args_size
*offset_ptr
;
5172 enum machine_mode passed_mode
;
5175 if (passed_mode
!= BLKmode
)
5177 if (GET_MODE_BITSIZE (passed_mode
) % PARM_BOUNDARY
)
5178 offset_ptr
->constant
5179 += (((GET_MODE_BITSIZE (passed_mode
) + PARM_BOUNDARY
- 1)
5180 / PARM_BOUNDARY
* PARM_BOUNDARY
/ BITS_PER_UNIT
)
5181 - GET_MODE_SIZE (passed_mode
));
5185 if (TREE_CODE (sizetree
) != INTEGER_CST
5186 || (TREE_INT_CST_LOW (sizetree
) * BITS_PER_UNIT
) % PARM_BOUNDARY
)
5188 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5189 tree s2
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
5191 ADD_PARM_SIZE (*offset_ptr
, s2
);
5192 SUB_PARM_SIZE (*offset_ptr
, sizetree
);
5198 /* Walk the tree of blocks describing the binding levels within a function
5199 and warn about uninitialized variables.
5200 This is done after calling flow_analysis and before global_alloc
5201 clobbers the pseudo-regs to hard regs. */
5204 uninitialized_vars_warning (block
)
5207 register tree decl
, sub
;
5208 for (decl
= BLOCK_VARS (block
); decl
; decl
= TREE_CHAIN (decl
))
5210 if (warn_uninitialized
5211 && TREE_CODE (decl
) == VAR_DECL
5212 /* These warnings are unreliable for and aggregates
5213 because assigning the fields one by one can fail to convince
5214 flow.c that the entire aggregate was initialized.
5215 Unions are troublesome because members may be shorter. */
5216 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl
))
5217 && DECL_RTL (decl
) != 0
5218 && GET_CODE (DECL_RTL (decl
)) == REG
5219 /* Global optimizations can make it difficult to determine if a
5220 particular variable has been initialized. However, a VAR_DECL
5221 with a nonzero DECL_INITIAL had an initializer, so do not
5222 claim it is potentially uninitialized.
5224 We do not care about the actual value in DECL_INITIAL, so we do
5225 not worry that it may be a dangling pointer. */
5226 && DECL_INITIAL (decl
) == NULL_TREE
5227 && regno_uninitialized (REGNO (DECL_RTL (decl
))))
5228 warning_with_decl (decl
,
5229 "`%s' might be used uninitialized in this function");
5231 && TREE_CODE (decl
) == VAR_DECL
5232 && DECL_RTL (decl
) != 0
5233 && GET_CODE (DECL_RTL (decl
)) == REG
5234 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl
))))
5235 warning_with_decl (decl
,
5236 "variable `%s' might be clobbered by `longjmp' or `vfork'");
5238 for (sub
= BLOCK_SUBBLOCKS (block
); sub
; sub
= TREE_CHAIN (sub
))
5239 uninitialized_vars_warning (sub
);
5242 /* Do the appropriate part of uninitialized_vars_warning
5243 but for arguments instead of local variables. */
5246 setjmp_args_warning ()
5249 for (decl
= DECL_ARGUMENTS (current_function_decl
);
5250 decl
; decl
= TREE_CHAIN (decl
))
5251 if (DECL_RTL (decl
) != 0
5252 && GET_CODE (DECL_RTL (decl
)) == REG
5253 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl
))))
5254 warning_with_decl (decl
, "argument `%s' might be clobbered by `longjmp' or `vfork'");
5257 /* If this function call setjmp, put all vars into the stack
5258 unless they were declared `register'. */
5261 setjmp_protect (block
)
5264 register tree decl
, sub
;
5265 for (decl
= BLOCK_VARS (block
); decl
; decl
= TREE_CHAIN (decl
))
5266 if ((TREE_CODE (decl
) == VAR_DECL
5267 || TREE_CODE (decl
) == PARM_DECL
)
5268 && DECL_RTL (decl
) != 0
5269 && (GET_CODE (DECL_RTL (decl
)) == REG
5270 || (GET_CODE (DECL_RTL (decl
)) == MEM
5271 && GET_CODE (XEXP (DECL_RTL (decl
), 0)) == ADDRESSOF
))
5272 /* If this variable came from an inline function, it must be
5273 that its life doesn't overlap the setjmp. If there was a
5274 setjmp in the function, it would already be in memory. We
5275 must exclude such variable because their DECL_RTL might be
5276 set to strange things such as virtual_stack_vars_rtx. */
5277 && ! DECL_FROM_INLINE (decl
)
5279 #ifdef NON_SAVING_SETJMP
5280 /* If longjmp doesn't restore the registers,
5281 don't put anything in them. */
5285 ! DECL_REGISTER (decl
)))
5286 put_var_into_stack (decl
);
5287 for (sub
= BLOCK_SUBBLOCKS (block
); sub
; sub
= TREE_CHAIN (sub
))
5288 setjmp_protect (sub
);
5291 /* Like the previous function, but for args instead of local variables. */
5294 setjmp_protect_args ()
5297 for (decl
= DECL_ARGUMENTS (current_function_decl
);
5298 decl
; decl
= TREE_CHAIN (decl
))
5299 if ((TREE_CODE (decl
) == VAR_DECL
5300 || TREE_CODE (decl
) == PARM_DECL
)
5301 && DECL_RTL (decl
) != 0
5302 && (GET_CODE (DECL_RTL (decl
)) == REG
5303 || (GET_CODE (DECL_RTL (decl
)) == MEM
5304 && GET_CODE (XEXP (DECL_RTL (decl
), 0)) == ADDRESSOF
))
5306 /* If longjmp doesn't restore the registers,
5307 don't put anything in them. */
5308 #ifdef NON_SAVING_SETJMP
5312 ! DECL_REGISTER (decl
)))
5313 put_var_into_stack (decl
);
5316 /* Return the context-pointer register corresponding to DECL,
5317 or 0 if it does not need one. */
5320 lookup_static_chain (decl
)
5323 tree context
= decl_function_context (decl
);
5327 || (TREE_CODE (decl
) == FUNCTION_DECL
&& DECL_NO_STATIC_CHAIN (decl
)))
5330 /* We treat inline_function_decl as an alias for the current function
5331 because that is the inline function whose vars, types, etc.
5332 are being merged into the current function.
5333 See expand_inline_function. */
5334 if (context
== current_function_decl
|| context
== inline_function_decl
)
5335 return virtual_stack_vars_rtx
;
5337 for (link
= context_display
; link
; link
= TREE_CHAIN (link
))
5338 if (TREE_PURPOSE (link
) == context
)
5339 return RTL_EXPR_RTL (TREE_VALUE (link
));
5344 /* Convert a stack slot address ADDR for variable VAR
5345 (from a containing function)
5346 into an address valid in this function (using a static chain). */
5349 fix_lexical_addr (addr
, var
)
5354 HOST_WIDE_INT displacement
;
5355 tree context
= decl_function_context (var
);
5356 struct function
*fp
;
5359 /* If this is the present function, we need not do anything. */
5360 if (context
== current_function_decl
|| context
== inline_function_decl
)
5363 for (fp
= outer_function_chain
; fp
; fp
= fp
->next
)
5364 if (fp
->decl
== context
)
5370 if (GET_CODE (addr
) == ADDRESSOF
&& GET_CODE (XEXP (addr
, 0)) == MEM
)
5371 addr
= XEXP (XEXP (addr
, 0), 0);
5373 /* Decode given address as base reg plus displacement. */
5374 if (GET_CODE (addr
) == REG
)
5375 basereg
= addr
, displacement
= 0;
5376 else if (GET_CODE (addr
) == PLUS
&& GET_CODE (XEXP (addr
, 1)) == CONST_INT
)
5377 basereg
= XEXP (addr
, 0), displacement
= INTVAL (XEXP (addr
, 1));
5381 /* We accept vars reached via the containing function's
5382 incoming arg pointer and via its stack variables pointer. */
5383 if (basereg
== fp
->internal_arg_pointer
)
5385 /* If reached via arg pointer, get the arg pointer value
5386 out of that function's stack frame.
5388 There are two cases: If a separate ap is needed, allocate a
5389 slot in the outer function for it and dereference it that way.
5390 This is correct even if the real ap is actually a pseudo.
5391 Otherwise, just adjust the offset from the frame pointer to
5394 #ifdef NEED_SEPARATE_AP
5397 if (fp
->x_arg_pointer_save_area
== 0)
5398 fp
->x_arg_pointer_save_area
5399 = assign_stack_local_1 (Pmode
, GET_MODE_SIZE (Pmode
), 0, fp
);
5401 addr
= fix_lexical_addr (XEXP (fp
->x_arg_pointer_save_area
, 0), var
);
5402 addr
= memory_address (Pmode
, addr
);
5404 base
= copy_to_reg (gen_rtx_MEM (Pmode
, addr
));
5406 displacement
+= (FIRST_PARM_OFFSET (context
) - STARTING_FRAME_OFFSET
);
5407 base
= lookup_static_chain (var
);
5411 else if (basereg
== virtual_stack_vars_rtx
)
5413 /* This is the same code as lookup_static_chain, duplicated here to
5414 avoid an extra call to decl_function_context. */
5417 for (link
= context_display
; link
; link
= TREE_CHAIN (link
))
5418 if (TREE_PURPOSE (link
) == context
)
5420 base
= RTL_EXPR_RTL (TREE_VALUE (link
));
5428 /* Use same offset, relative to appropriate static chain or argument
5430 return plus_constant (base
, displacement
);
5433 /* Return the address of the trampoline for entering nested fn FUNCTION.
5434 If necessary, allocate a trampoline (in the stack frame)
5435 and emit rtl to initialize its contents (at entry to this function). */
5438 trampoline_address (function
)
5444 struct function
*fp
;
5447 /* Find an existing trampoline and return it. */
5448 for (link
= trampoline_list
; link
; link
= TREE_CHAIN (link
))
5449 if (TREE_PURPOSE (link
) == function
)
5451 round_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link
)), 0));
5453 for (fp
= outer_function_chain
; fp
; fp
= fp
->next
)
5454 for (link
= fp
->x_trampoline_list
; link
; link
= TREE_CHAIN (link
))
5455 if (TREE_PURPOSE (link
) == function
)
5457 tramp
= fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link
)), 0),
5459 return round_trampoline_addr (tramp
);
5462 /* None exists; we must make one. */
5464 /* Find the `struct function' for the function containing FUNCTION. */
5466 fn_context
= decl_function_context (function
);
5467 if (fn_context
!= current_function_decl
5468 && fn_context
!= inline_function_decl
)
5469 for (fp
= outer_function_chain
; fp
; fp
= fp
->next
)
5470 if (fp
->decl
== fn_context
)
5473 /* Allocate run-time space for this trampoline
5474 (usually in the defining function's stack frame). */
5475 #ifdef ALLOCATE_TRAMPOLINE
5476 tramp
= ALLOCATE_TRAMPOLINE (fp
);
5478 /* If rounding needed, allocate extra space
5479 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5480 #ifdef TRAMPOLINE_ALIGNMENT
5481 #define TRAMPOLINE_REAL_SIZE \
5482 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5484 #define TRAMPOLINE_REAL_SIZE (TRAMPOLINE_SIZE)
5486 tramp
= assign_stack_local_1 (BLKmode
, TRAMPOLINE_REAL_SIZE
, 0,
5490 /* Record the trampoline for reuse and note it for later initialization
5491 by expand_function_end. */
5494 push_obstacks (fp
->function_maybepermanent_obstack
,
5495 fp
->function_maybepermanent_obstack
);
5496 rtlexp
= make_node (RTL_EXPR
);
5497 RTL_EXPR_RTL (rtlexp
) = tramp
;
5498 fp
->x_trampoline_list
= tree_cons (function
, rtlexp
,
5499 fp
->x_trampoline_list
);
5504 /* Make the RTL_EXPR node temporary, not momentary, so that the
5505 trampoline_list doesn't become garbage. */
5506 int momentary
= suspend_momentary ();
5507 rtlexp
= make_node (RTL_EXPR
);
5508 resume_momentary (momentary
);
5510 RTL_EXPR_RTL (rtlexp
) = tramp
;
5511 trampoline_list
= tree_cons (function
, rtlexp
, trampoline_list
);
5514 tramp
= fix_lexical_addr (XEXP (tramp
, 0), function
);
5515 return round_trampoline_addr (tramp
);
5518 /* Given a trampoline address,
5519 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5522 round_trampoline_addr (tramp
)
5525 #ifdef TRAMPOLINE_ALIGNMENT
5526 /* Round address up to desired boundary. */
5527 rtx temp
= gen_reg_rtx (Pmode
);
5528 temp
= expand_binop (Pmode
, add_optab
, tramp
,
5529 GEN_INT (TRAMPOLINE_ALIGNMENT
/ BITS_PER_UNIT
- 1),
5530 temp
, 0, OPTAB_LIB_WIDEN
);
5531 tramp
= expand_binop (Pmode
, and_optab
, temp
,
5532 GEN_INT (- TRAMPOLINE_ALIGNMENT
/ BITS_PER_UNIT
),
5533 temp
, 0, OPTAB_LIB_WIDEN
);
5538 /* Put all this function's BLOCK nodes including those that are chained
5539 onto the first block into a vector, and return it.
5540 Also store in each NOTE for the beginning or end of a block
5541 the index of that block in the vector.
5542 The arguments are BLOCK, the chain of top-level blocks of the function,
5543 and INSNS, the insn chain of the function. */
5549 tree
*block_vector
, *last_block_vector
;
5551 tree block
= DECL_INITIAL (current_function_decl
);
5556 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5557 depth-first order. */
5558 block_vector
= get_block_vector (block
, &n_blocks
);
5559 block_stack
= (tree
*) xmalloc (n_blocks
* sizeof (tree
));
5561 last_block_vector
= identify_blocks_1 (get_insns (),
5563 block_vector
+ n_blocks
,
5566 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5567 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5568 if (0 && last_block_vector
!= block_vector
+ n_blocks
)
5571 free (block_vector
);
5575 /* Subroutine of identify_blocks. Do the block substitution on the
5576 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
5578 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5579 BLOCK_VECTOR is incremented for each block seen. */
5582 identify_blocks_1 (insns
, block_vector
, end_block_vector
, orig_block_stack
)
5585 tree
*end_block_vector
;
5586 tree
*orig_block_stack
;
5589 tree
*block_stack
= orig_block_stack
;
5591 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
5593 if (GET_CODE (insn
) == NOTE
)
5595 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_BEG
)
5599 /* If there are more block notes than BLOCKs, something
5601 if (block_vector
== end_block_vector
)
5604 b
= *block_vector
++;
5605 NOTE_BLOCK (insn
) = b
;
5608 else if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_END
)
5610 /* If there are more NOTE_INSN_BLOCK_ENDs than
5611 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
5612 if (block_stack
== orig_block_stack
)
5615 NOTE_BLOCK (insn
) = *--block_stack
;
5618 else if (GET_CODE (insn
) == CALL_INSN
5619 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
5621 rtx cp
= PATTERN (insn
);
5623 block_vector
= identify_blocks_1 (XEXP (cp
, 0), block_vector
,
5624 end_block_vector
, block_stack
);
5626 block_vector
= identify_blocks_1 (XEXP (cp
, 1), block_vector
,
5627 end_block_vector
, block_stack
);
5629 block_vector
= identify_blocks_1 (XEXP (cp
, 2), block_vector
,
5630 end_block_vector
, block_stack
);
5634 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
5635 something is badly wrong. */
5636 if (block_stack
!= orig_block_stack
)
5639 return block_vector
;
5642 /* Identify BLOCKs referenced by more than one
5643 NOTE_INSN_BLOCK_{BEG,END}, and create duplicate blocks. */
5648 tree block
= DECL_INITIAL (current_function_decl
);
5649 varray_type block_stack
;
5651 if (block
== NULL_TREE
)
5654 VARRAY_TREE_INIT (block_stack
, 10, "block_stack");
5656 /* Prune the old trees away, so that they don't get in the way. */
5657 BLOCK_SUBBLOCKS (block
) = NULL_TREE
;
5658 BLOCK_CHAIN (block
) = NULL_TREE
;
5660 reorder_blocks_1 (get_insns (), block
, &block_stack
);
5662 BLOCK_SUBBLOCKS (block
)
5663 = blocks_nreverse (BLOCK_SUBBLOCKS (block
));
5665 VARRAY_FREE (block_stack
);
5668 /* Helper function for reorder_blocks. Process the insn chain beginning
5669 at INSNS. Recurse for CALL_PLACEHOLDER insns. */
5672 reorder_blocks_1 (insns
, current_block
, p_block_stack
)
5675 varray_type
*p_block_stack
;
5679 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
5681 if (GET_CODE (insn
) == NOTE
)
5683 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_BEG
)
5685 tree block
= NOTE_BLOCK (insn
);
5686 /* If we have seen this block before, copy it. */
5687 if (TREE_ASM_WRITTEN (block
))
5689 block
= copy_node (block
);
5690 NOTE_BLOCK (insn
) = block
;
5692 BLOCK_SUBBLOCKS (block
) = 0;
5693 TREE_ASM_WRITTEN (block
) = 1;
5694 BLOCK_SUPERCONTEXT (block
) = current_block
;
5695 BLOCK_CHAIN (block
) = BLOCK_SUBBLOCKS (current_block
);
5696 BLOCK_SUBBLOCKS (current_block
) = block
;
5697 current_block
= block
;
5698 VARRAY_PUSH_TREE (*p_block_stack
, block
);
5700 else if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_END
)
5702 NOTE_BLOCK (insn
) = VARRAY_TOP_TREE (*p_block_stack
);
5703 VARRAY_POP (*p_block_stack
);
5704 BLOCK_SUBBLOCKS (current_block
)
5705 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block
));
5706 current_block
= BLOCK_SUPERCONTEXT (current_block
);
5709 else if (GET_CODE (insn
) == CALL_INSN
5710 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
5712 rtx cp
= PATTERN (insn
);
5713 reorder_blocks_1 (XEXP (cp
, 0), current_block
, p_block_stack
);
5715 reorder_blocks_1 (XEXP (cp
, 1), current_block
, p_block_stack
);
5717 reorder_blocks_1 (XEXP (cp
, 2), current_block
, p_block_stack
);
5722 /* Reverse the order of elements in the chain T of blocks,
5723 and return the new head of the chain (old last element). */
5729 register tree prev
= 0, decl
, next
;
5730 for (decl
= t
; decl
; decl
= next
)
5732 next
= BLOCK_CHAIN (decl
);
5733 BLOCK_CHAIN (decl
) = prev
;
5739 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
5740 non-NULL, list them all into VECTOR, in a depth-first preorder
5741 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
5745 all_blocks (block
, vector
)
5753 TREE_ASM_WRITTEN (block
) = 0;
5755 /* Record this block. */
5757 vector
[n_blocks
] = block
;
5761 /* Record the subblocks, and their subblocks... */
5762 n_blocks
+= all_blocks (BLOCK_SUBBLOCKS (block
),
5763 vector
? vector
+ n_blocks
: 0);
5764 block
= BLOCK_CHAIN (block
);
5770 /* Return a vector containing all the blocks rooted at BLOCK. The
5771 number of elements in the vector is stored in N_BLOCKS_P. The
5772 vector is dynamically allocated; it is the caller's responsibility
5773 to call `free' on the pointer returned. */
5776 get_block_vector (block
, n_blocks_p
)
5782 *n_blocks_p
= all_blocks (block
, NULL
);
5783 block_vector
= (tree
*) xmalloc (*n_blocks_p
* sizeof (tree
));
5784 all_blocks (block
, block_vector
);
5786 return block_vector
;
5789 static int next_block_index
= 2;
5791 /* Set BLOCK_NUMBER for all the blocks in FN. */
5801 /* For SDB and XCOFF debugging output, we start numbering the blocks
5802 from 1 within each function, rather than keeping a running
5804 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
5805 if (write_symbols
== SDB_DEBUG
|| write_symbols
== XCOFF_DEBUG
)
5806 next_block_index
= 1;
5809 block_vector
= get_block_vector (DECL_INITIAL (fn
), &n_blocks
);
5811 /* The top-level BLOCK isn't numbered at all. */
5812 for (i
= 1; i
< n_blocks
; ++i
)
5813 /* We number the blocks from two. */
5814 BLOCK_NUMBER (block_vector
[i
]) = next_block_index
++;
5816 free (block_vector
);
5822 /* Allocate a function structure and reset its contents to the defaults. */
5824 prepare_function_start ()
5826 cfun
= (struct function
*) xcalloc (1, sizeof (struct function
));
5828 init_stmt_for_function ();
5829 init_eh_for_function ();
5831 cse_not_expected
= ! optimize
;
5833 /* Caller save not needed yet. */
5834 caller_save_needed
= 0;
5836 /* No stack slots have been made yet. */
5837 stack_slot_list
= 0;
5839 current_function_has_nonlocal_label
= 0;
5840 current_function_has_nonlocal_goto
= 0;
5842 /* There is no stack slot for handling nonlocal gotos. */
5843 nonlocal_goto_handler_slots
= 0;
5844 nonlocal_goto_stack_level
= 0;
5846 /* No labels have been declared for nonlocal use. */
5847 nonlocal_labels
= 0;
5848 nonlocal_goto_handler_labels
= 0;
5850 /* No function calls so far in this function. */
5851 function_call_count
= 0;
5853 /* No parm regs have been allocated.
5854 (This is important for output_inline_function.) */
5855 max_parm_reg
= LAST_VIRTUAL_REGISTER
+ 1;
5857 /* Initialize the RTL mechanism. */
5860 /* Initialize the queue of pending postincrement and postdecrements,
5861 and some other info in expr.c. */
5864 /* We haven't done register allocation yet. */
5867 init_varasm_status (cfun
);
5869 /* Clear out data used for inlining. */
5870 cfun
->inlinable
= 0;
5871 cfun
->original_decl_initial
= 0;
5872 cfun
->original_arg_vector
= 0;
5874 #ifdef STACK_BOUNDARY
5875 cfun
->stack_alignment_needed
= STACK_BOUNDARY
;
5876 cfun
->preferred_stack_boundary
= STACK_BOUNDARY
;
5878 cfun
->stack_alignment_needed
= 0;
5879 cfun
->preferred_stack_boundary
= 0;
5882 /* Set if a call to setjmp is seen. */
5883 current_function_calls_setjmp
= 0;
5885 /* Set if a call to longjmp is seen. */
5886 current_function_calls_longjmp
= 0;
5888 current_function_calls_alloca
= 0;
5889 current_function_contains_functions
= 0;
5890 current_function_is_leaf
= 0;
5891 current_function_nothrow
= 0;
5892 current_function_sp_is_unchanging
= 0;
5893 current_function_uses_only_leaf_regs
= 0;
5894 current_function_has_computed_jump
= 0;
5895 current_function_is_thunk
= 0;
5897 current_function_returns_pcc_struct
= 0;
5898 current_function_returns_struct
= 0;
5899 current_function_epilogue_delay_list
= 0;
5900 current_function_uses_const_pool
= 0;
5901 current_function_uses_pic_offset_table
= 0;
5902 current_function_cannot_inline
= 0;
5904 /* We have not yet needed to make a label to jump to for tail-recursion. */
5905 tail_recursion_label
= 0;
5907 /* We haven't had a need to make a save area for ap yet. */
5908 arg_pointer_save_area
= 0;
5910 /* No stack slots allocated yet. */
5913 /* No SAVE_EXPRs in this function yet. */
5916 /* No RTL_EXPRs in this function yet. */
5919 /* Set up to allocate temporaries. */
5922 /* Indicate that we need to distinguish between the return value of the
5923 present function and the return value of a function being called. */
5924 rtx_equal_function_value_matters
= 1;
5926 /* Indicate that we have not instantiated virtual registers yet. */
5927 virtuals_instantiated
= 0;
5929 /* Indicate we have no need of a frame pointer yet. */
5930 frame_pointer_needed
= 0;
5932 /* By default assume not varargs or stdarg. */
5933 current_function_varargs
= 0;
5934 current_function_stdarg
= 0;
5936 /* We haven't made any trampolines for this function yet. */
5937 trampoline_list
= 0;
5939 init_pending_stack_adjust ();
5940 inhibit_defer_pop
= 0;
5942 current_function_outgoing_args_size
= 0;
5944 if (init_lang_status
)
5945 (*init_lang_status
) (cfun
);
5946 if (init_machine_status
)
5947 (*init_machine_status
) (cfun
);
5950 /* Initialize the rtl expansion mechanism so that we can do simple things
5951 like generate sequences. This is used to provide a context during global
5952 initialization of some passes. */
5954 init_dummy_function_start ()
5956 prepare_function_start ();
5959 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
5960 and initialize static variables for generating RTL for the statements
5964 init_function_start (subr
, filename
, line
)
5969 prepare_function_start ();
5971 /* Remember this function for later. */
5972 cfun
->next_global
= all_functions
;
5973 all_functions
= cfun
;
5975 current_function_name
= (*decl_printable_name
) (subr
, 2);
5978 /* Nonzero if this is a nested function that uses a static chain. */
5980 current_function_needs_context
5981 = (decl_function_context (current_function_decl
) != 0
5982 && ! DECL_NO_STATIC_CHAIN (current_function_decl
));
5984 /* Within function body, compute a type's size as soon it is laid out. */
5985 immediate_size_expand
++;
5987 /* Prevent ever trying to delete the first instruction of a function.
5988 Also tell final how to output a linenum before the function prologue.
5989 Note linenums could be missing, e.g. when compiling a Java .class file. */
5991 emit_line_note (filename
, line
);
5993 /* Make sure first insn is a note even if we don't want linenums.
5994 This makes sure the first insn will never be deleted.
5995 Also, final expects a note to appear there. */
5996 emit_note (NULL_PTR
, NOTE_INSN_DELETED
);
5998 /* Set flags used by final.c. */
5999 if (aggregate_value_p (DECL_RESULT (subr
)))
6001 #ifdef PCC_STATIC_STRUCT_RETURN
6002 current_function_returns_pcc_struct
= 1;
6004 current_function_returns_struct
= 1;
6007 /* Warn if this value is an aggregate type,
6008 regardless of which calling convention we are using for it. */
6009 if (warn_aggregate_return
6010 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr
))))
6011 warning ("function returns an aggregate");
6013 current_function_returns_pointer
6014 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr
)));
6017 /* Make sure all values used by the optimization passes have sane
6020 init_function_for_compilation ()
6024 /* No prologue/epilogue insns yet. */
6025 VARRAY_GROW (prologue
, 0);
6026 VARRAY_GROW (epilogue
, 0);
6027 VARRAY_GROW (sibcall_epilogue
, 0);
6030 /* Indicate that the current function uses extra args
6031 not explicitly mentioned in the argument list in any fashion. */
6036 current_function_varargs
= 1;
6039 /* Expand a call to __main at the beginning of a possible main function. */
6041 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6042 #undef HAS_INIT_SECTION
6043 #define HAS_INIT_SECTION
6047 expand_main_function ()
6049 #if !defined (HAS_INIT_SECTION)
6050 emit_library_call (gen_rtx_SYMBOL_REF (Pmode
, NAME__MAIN
), 0,
6052 #endif /* not HAS_INIT_SECTION */
6055 extern struct obstack permanent_obstack
;
6057 /* Start the RTL for a new function, and set variables used for
6059 SUBR is the FUNCTION_DECL node.
6060 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6061 the function's parameters, which must be run at any return statement. */
6064 expand_function_start (subr
, parms_have_cleanups
)
6066 int parms_have_cleanups
;
6069 rtx last_ptr
= NULL_RTX
;
6071 /* Make sure volatile mem refs aren't considered
6072 valid operands of arithmetic insns. */
6073 init_recog_no_volatile ();
6075 /* Set this before generating any memory accesses. */
6076 current_function_check_memory_usage
6077 = (flag_check_memory_usage
6078 && ! DECL_NO_CHECK_MEMORY_USAGE (current_function_decl
));
6080 current_function_instrument_entry_exit
6081 = (flag_instrument_function_entry_exit
6082 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr
));
6084 current_function_limit_stack
6085 = (stack_limit_rtx
!= NULL_RTX
&& ! DECL_NO_LIMIT_STACK (subr
));
6087 /* If function gets a static chain arg, store it in the stack frame.
6088 Do this first, so it gets the first stack slot offset. */
6089 if (current_function_needs_context
)
6091 last_ptr
= assign_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0);
6093 /* Delay copying static chain if it is not a register to avoid
6094 conflicts with regs used for parameters. */
6095 if (! SMALL_REGISTER_CLASSES
6096 || GET_CODE (static_chain_incoming_rtx
) == REG
)
6097 emit_move_insn (last_ptr
, static_chain_incoming_rtx
);
6100 /* If the parameters of this function need cleaning up, get a label
6101 for the beginning of the code which executes those cleanups. This must
6102 be done before doing anything with return_label. */
6103 if (parms_have_cleanups
)
6104 cleanup_label
= gen_label_rtx ();
6108 /* Make the label for return statements to jump to, if this machine
6109 does not have a one-instruction return and uses an epilogue,
6110 or if it returns a structure, or if it has parm cleanups. */
6112 if (cleanup_label
== 0 && HAVE_return
6113 && ! current_function_instrument_entry_exit
6114 && ! current_function_returns_pcc_struct
6115 && ! (current_function_returns_struct
&& ! optimize
))
6118 return_label
= gen_label_rtx ();
6120 return_label
= gen_label_rtx ();
6123 /* Initialize rtx used to return the value. */
6124 /* Do this before assign_parms so that we copy the struct value address
6125 before any library calls that assign parms might generate. */
6127 /* Decide whether to return the value in memory or in a register. */
6128 if (aggregate_value_p (DECL_RESULT (subr
)))
6130 /* Returning something that won't go in a register. */
6131 register rtx value_address
= 0;
6133 #ifdef PCC_STATIC_STRUCT_RETURN
6134 if (current_function_returns_pcc_struct
)
6136 int size
= int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr
)));
6137 value_address
= assemble_static_space (size
);
6142 /* Expect to be passed the address of a place to store the value.
6143 If it is passed as an argument, assign_parms will take care of
6145 if (struct_value_incoming_rtx
)
6147 value_address
= gen_reg_rtx (Pmode
);
6148 emit_move_insn (value_address
, struct_value_incoming_rtx
);
6153 DECL_RTL (DECL_RESULT (subr
))
6154 = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr
)), value_address
);
6155 MEM_SET_IN_STRUCT_P (DECL_RTL (DECL_RESULT (subr
)),
6156 AGGREGATE_TYPE_P (TREE_TYPE
6161 else if (DECL_MODE (DECL_RESULT (subr
)) == VOIDmode
)
6162 /* If return mode is void, this decl rtl should not be used. */
6163 DECL_RTL (DECL_RESULT (subr
)) = 0;
6164 else if (parms_have_cleanups
|| current_function_instrument_entry_exit
)
6166 /* If function will end with cleanup code for parms,
6167 compute the return values into a pseudo reg,
6168 which we will copy into the true return register
6169 after the cleanups are done. */
6171 enum machine_mode mode
= DECL_MODE (DECL_RESULT (subr
));
6173 #ifdef PROMOTE_FUNCTION_RETURN
6174 tree type
= TREE_TYPE (DECL_RESULT (subr
));
6175 int unsignedp
= TREE_UNSIGNED (type
);
6177 mode
= promote_mode (type
, mode
, &unsignedp
, 1);
6180 DECL_RTL (DECL_RESULT (subr
)) = gen_reg_rtx (mode
);
6183 /* Scalar, returned in a register. */
6185 DECL_RTL (DECL_RESULT (subr
))
6186 = hard_function_value (TREE_TYPE (DECL_RESULT (subr
)), subr
, 1);
6188 /* Mark this reg as the function's return value. */
6189 if (GET_CODE (DECL_RTL (DECL_RESULT (subr
))) == REG
)
6191 REG_FUNCTION_VALUE_P (DECL_RTL (DECL_RESULT (subr
))) = 1;
6192 /* Needed because we may need to move this to memory
6193 in case it's a named return value whose address is taken. */
6194 DECL_REGISTER (DECL_RESULT (subr
)) = 1;
6198 /* Initialize rtx for parameters and local variables.
6199 In some cases this requires emitting insns. */
6201 assign_parms (subr
);
6203 /* Copy the static chain now if it wasn't a register. The delay is to
6204 avoid conflicts with the parameter passing registers. */
6206 if (SMALL_REGISTER_CLASSES
&& current_function_needs_context
)
6207 if (GET_CODE (static_chain_incoming_rtx
) != REG
)
6208 emit_move_insn (last_ptr
, static_chain_incoming_rtx
);
6210 /* The following was moved from init_function_start.
6211 The move is supposed to make sdb output more accurate. */
6212 /* Indicate the beginning of the function body,
6213 as opposed to parm setup. */
6214 emit_note (NULL_PTR
, NOTE_INSN_FUNCTION_BEG
);
6216 if (GET_CODE (get_last_insn ()) != NOTE
)
6217 emit_note (NULL_PTR
, NOTE_INSN_DELETED
);
6218 parm_birth_insn
= get_last_insn ();
6220 context_display
= 0;
6221 if (current_function_needs_context
)
6223 /* Fetch static chain values for containing functions. */
6224 tem
= decl_function_context (current_function_decl
);
6225 /* Copy the static chain pointer into a pseudo. If we have
6226 small register classes, copy the value from memory if
6227 static_chain_incoming_rtx is a REG. */
6230 /* If the static chain originally came in a register, put it back
6231 there, then move it out in the next insn. The reason for
6232 this peculiar code is to satisfy function integration. */
6233 if (SMALL_REGISTER_CLASSES
6234 && GET_CODE (static_chain_incoming_rtx
) == REG
)
6235 emit_move_insn (static_chain_incoming_rtx
, last_ptr
);
6236 last_ptr
= copy_to_reg (static_chain_incoming_rtx
);
6241 tree rtlexp
= make_node (RTL_EXPR
);
6243 RTL_EXPR_RTL (rtlexp
) = last_ptr
;
6244 context_display
= tree_cons (tem
, rtlexp
, context_display
);
6245 tem
= decl_function_context (tem
);
6248 /* Chain thru stack frames, assuming pointer to next lexical frame
6249 is found at the place we always store it. */
6250 #ifdef FRAME_GROWS_DOWNWARD
6251 last_ptr
= plus_constant (last_ptr
, - GET_MODE_SIZE (Pmode
));
6253 last_ptr
= copy_to_reg (gen_rtx_MEM (Pmode
,
6254 memory_address (Pmode
,
6257 /* If we are not optimizing, ensure that we know that this
6258 piece of context is live over the entire function. */
6260 save_expr_regs
= gen_rtx_EXPR_LIST (VOIDmode
, last_ptr
,
6265 if (current_function_instrument_entry_exit
)
6267 rtx fun
= DECL_RTL (current_function_decl
);
6268 if (GET_CODE (fun
) == MEM
)
6269 fun
= XEXP (fun
, 0);
6272 emit_library_call (profile_function_entry_libfunc
, 0, VOIDmode
, 2,
6274 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS
,
6276 hard_frame_pointer_rtx
),
6280 /* After the display initializations is where the tail-recursion label
6281 should go, if we end up needing one. Ensure we have a NOTE here
6282 since some things (like trampolines) get placed before this. */
6283 tail_recursion_reentry
= emit_note (NULL_PTR
, NOTE_INSN_DELETED
);
6285 /* Evaluate now the sizes of any types declared among the arguments. */
6286 for (tem
= nreverse (get_pending_sizes ()); tem
; tem
= TREE_CHAIN (tem
))
6288 expand_expr (TREE_VALUE (tem
), const0_rtx
, VOIDmode
,
6289 EXPAND_MEMORY_USE_BAD
);
6290 /* Flush the queue in case this parameter declaration has
6295 /* Make sure there is a line number after the function entry setup code. */
6296 force_next_line_note ();
6299 /* Undo the effects of init_dummy_function_start. */
6301 expand_dummy_function_end ()
6303 /* End any sequences that failed to be closed due to syntax errors. */
6304 while (in_sequence_p ())
6307 /* Outside function body, can't compute type's actual size
6308 until next function's body starts. */
6310 free_after_parsing (cfun
);
6311 free_after_compilation (cfun
);
6316 /* Call DOIT for each hard register used as a return value from
6317 the current function. */
6320 diddle_return_value (doit
, arg
)
6321 void (*doit
) PARAMS ((rtx
, void *));
6324 rtx outgoing
= current_function_return_rtx
;
6329 if (GET_CODE (outgoing
) == REG
6330 && REGNO (outgoing
) >= FIRST_PSEUDO_REGISTER
)
6332 tree type
= TREE_TYPE (DECL_RESULT (current_function_decl
));
6333 #ifdef FUNCTION_OUTGOING_VALUE
6334 outgoing
= FUNCTION_OUTGOING_VALUE (type
, current_function_decl
);
6336 outgoing
= FUNCTION_VALUE (type
, current_function_decl
);
6338 /* If this is a BLKmode structure being returned in registers, then use
6339 the mode computed in expand_return. */
6340 if (GET_MODE (outgoing
) == BLKmode
)
6342 GET_MODE (DECL_RTL (DECL_RESULT (current_function_decl
))));
6345 if (GET_CODE (outgoing
) == REG
)
6346 (*doit
) (outgoing
, arg
);
6347 else if (GET_CODE (outgoing
) == PARALLEL
)
6351 for (i
= 0; i
< XVECLEN (outgoing
, 0); i
++)
6353 rtx x
= XEXP (XVECEXP (outgoing
, 0, i
), 0);
6355 if (GET_CODE (x
) == REG
&& REGNO (x
) < FIRST_PSEUDO_REGISTER
)
6362 do_clobber_return_reg (reg
, arg
)
6364 void *arg ATTRIBUTE_UNUSED
;
6366 emit_insn (gen_rtx_CLOBBER (VOIDmode
, reg
));
6370 clobber_return_register ()
6372 diddle_return_value (do_clobber_return_reg
, NULL
);
6376 do_use_return_reg (reg
, arg
)
6378 void *arg ATTRIBUTE_UNUSED
;
6380 emit_insn (gen_rtx_USE (VOIDmode
, reg
));
6384 use_return_register ()
6386 diddle_return_value (do_use_return_reg
, NULL
);
6389 /* Generate RTL for the end of the current function.
6390 FILENAME and LINE are the current position in the source file.
6392 It is up to language-specific callers to do cleanups for parameters--
6393 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
6396 expand_function_end (filename
, line
, end_bindings
)
6403 #ifdef TRAMPOLINE_TEMPLATE
6404 static rtx initial_trampoline
;
6407 finish_expr_for_function ();
6409 #ifdef NON_SAVING_SETJMP
6410 /* Don't put any variables in registers if we call setjmp
6411 on a machine that fails to restore the registers. */
6412 if (NON_SAVING_SETJMP
&& current_function_calls_setjmp
)
6414 if (DECL_INITIAL (current_function_decl
) != error_mark_node
)
6415 setjmp_protect (DECL_INITIAL (current_function_decl
));
6417 setjmp_protect_args ();
6421 /* Save the argument pointer if a save area was made for it. */
6422 if (arg_pointer_save_area
)
6424 /* arg_pointer_save_area may not be a valid memory address, so we
6425 have to check it and fix it if necessary. */
6428 emit_move_insn (validize_mem (arg_pointer_save_area
),
6429 virtual_incoming_args_rtx
);
6430 seq
= gen_sequence ();
6432 emit_insn_before (seq
, tail_recursion_reentry
);
6435 /* Initialize any trampolines required by this function. */
6436 for (link
= trampoline_list
; link
; link
= TREE_CHAIN (link
))
6438 tree function
= TREE_PURPOSE (link
);
6439 rtx context ATTRIBUTE_UNUSED
= lookup_static_chain (function
);
6440 rtx tramp
= RTL_EXPR_RTL (TREE_VALUE (link
));
6441 #ifdef TRAMPOLINE_TEMPLATE
6446 #ifdef TRAMPOLINE_TEMPLATE
6447 /* First make sure this compilation has a template for
6448 initializing trampolines. */
6449 if (initial_trampoline
== 0)
6451 end_temporary_allocation ();
6453 = gen_rtx_MEM (BLKmode
, assemble_trampoline_template ());
6454 resume_temporary_allocation ();
6456 ggc_add_rtx_root (&initial_trampoline
, 1);
6460 /* Generate insns to initialize the trampoline. */
6462 tramp
= round_trampoline_addr (XEXP (tramp
, 0));
6463 #ifdef TRAMPOLINE_TEMPLATE
6464 blktramp
= change_address (initial_trampoline
, BLKmode
, tramp
);
6465 emit_block_move (blktramp
, initial_trampoline
,
6466 GEN_INT (TRAMPOLINE_SIZE
),
6467 TRAMPOLINE_ALIGNMENT
);
6469 INITIALIZE_TRAMPOLINE (tramp
, XEXP (DECL_RTL (function
), 0), context
);
6473 /* Put those insns at entry to the containing function (this one). */
6474 emit_insns_before (seq
, tail_recursion_reentry
);
6477 /* If we are doing stack checking and this function makes calls,
6478 do a stack probe at the start of the function to ensure we have enough
6479 space for another stack frame. */
6480 if (flag_stack_check
&& ! STACK_CHECK_BUILTIN
)
6484 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
6485 if (GET_CODE (insn
) == CALL_INSN
)
6488 probe_stack_range (STACK_CHECK_PROTECT
,
6489 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE
));
6492 emit_insns_before (seq
, tail_recursion_reentry
);
6497 /* Warn about unused parms if extra warnings were specified. */
6498 if (warn_unused
&& extra_warnings
)
6502 for (decl
= DECL_ARGUMENTS (current_function_decl
);
6503 decl
; decl
= TREE_CHAIN (decl
))
6504 if (! TREE_USED (decl
) && TREE_CODE (decl
) == PARM_DECL
6505 && DECL_NAME (decl
) && ! DECL_ARTIFICIAL (decl
))
6506 warning_with_decl (decl
, "unused parameter `%s'");
6509 /* Delete handlers for nonlocal gotos if nothing uses them. */
6510 if (nonlocal_goto_handler_slots
!= 0
6511 && ! current_function_has_nonlocal_label
)
6514 /* End any sequences that failed to be closed due to syntax errors. */
6515 while (in_sequence_p ())
6518 /* Outside function body, can't compute type's actual size
6519 until next function's body starts. */
6520 immediate_size_expand
--;
6522 clear_pending_stack_adjust ();
6523 do_pending_stack_adjust ();
6525 /* Mark the end of the function body.
6526 If control reaches this insn, the function can drop through
6527 without returning a value. */
6528 emit_note (NULL_PTR
, NOTE_INSN_FUNCTION_END
);
6530 /* Must mark the last line number note in the function, so that the test
6531 coverage code can avoid counting the last line twice. This just tells
6532 the code to ignore the immediately following line note, since there
6533 already exists a copy of this note somewhere above. This line number
6534 note is still needed for debugging though, so we can't delete it. */
6535 if (flag_test_coverage
)
6536 emit_note (NULL_PTR
, NOTE_REPEATED_LINE_NUMBER
);
6538 /* Output a linenumber for the end of the function.
6539 SDB depends on this. */
6540 emit_line_note_force (filename
, line
);
6542 /* Output the label for the actual return from the function,
6543 if one is expected. This happens either because a function epilogue
6544 is used instead of a return instruction, or because a return was done
6545 with a goto in order to run local cleanups, or because of pcc-style
6546 structure returning. */
6550 /* Before the return label, clobber the return registers so that
6551 they are not propogated live to the rest of the function. This
6552 can only happen with functions that drop through; if there had
6553 been a return statement, there would have either been a return
6554 rtx, or a jump to the return label. */
6555 clobber_return_register ();
6557 emit_label (return_label
);
6560 /* C++ uses this. */
6562 expand_end_bindings (0, 0, 0);
6564 /* Now handle any leftover exception regions that may have been
6565 created for the parameters. */
6567 rtx last
= get_last_insn ();
6570 expand_leftover_cleanups ();
6572 /* If there are any catch_clauses remaining, output them now. */
6573 emit_insns (catch_clauses
);
6574 catch_clauses
= catch_clauses_last
= NULL_RTX
;
6575 /* If the above emitted any code, may sure we jump around it. */
6576 if (last
!= get_last_insn ())
6578 label
= gen_label_rtx ();
6579 last
= emit_jump_insn_after (gen_jump (label
), last
);
6580 last
= emit_barrier_after (last
);
6585 if (current_function_instrument_entry_exit
)
6587 rtx fun
= DECL_RTL (current_function_decl
);
6588 if (GET_CODE (fun
) == MEM
)
6589 fun
= XEXP (fun
, 0);
6592 emit_library_call (profile_function_exit_libfunc
, 0, VOIDmode
, 2,
6594 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS
,
6596 hard_frame_pointer_rtx
),
6600 /* If we had calls to alloca, and this machine needs
6601 an accurate stack pointer to exit the function,
6602 insert some code to save and restore the stack pointer. */
6603 #ifdef EXIT_IGNORE_STACK
6604 if (! EXIT_IGNORE_STACK
)
6606 if (current_function_calls_alloca
)
6610 emit_stack_save (SAVE_FUNCTION
, &tem
, parm_birth_insn
);
6611 emit_stack_restore (SAVE_FUNCTION
, tem
, NULL_RTX
);
6614 /* If scalar return value was computed in a pseudo-reg,
6615 copy that to the hard return register. */
6616 if (DECL_RTL (DECL_RESULT (current_function_decl
)) != 0
6617 && GET_CODE (DECL_RTL (DECL_RESULT (current_function_decl
))) == REG
6618 && (REGNO (DECL_RTL (DECL_RESULT (current_function_decl
)))
6619 >= FIRST_PSEUDO_REGISTER
))
6621 rtx real_decl_result
;
6623 #ifdef FUNCTION_OUTGOING_VALUE
6625 = FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl
)),
6626 current_function_decl
);
6629 = FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl
)),
6630 current_function_decl
);
6632 REG_FUNCTION_VALUE_P (real_decl_result
) = 1;
6633 /* If this is a BLKmode structure being returned in registers, then use
6634 the mode computed in expand_return. */
6635 if (GET_MODE (real_decl_result
) == BLKmode
)
6636 PUT_MODE (real_decl_result
,
6637 GET_MODE (DECL_RTL (DECL_RESULT (current_function_decl
))));
6638 emit_move_insn (real_decl_result
,
6639 DECL_RTL (DECL_RESULT (current_function_decl
)));
6641 /* The delay slot scheduler assumes that current_function_return_rtx
6642 holds the hard register containing the return value, not a temporary
6644 current_function_return_rtx
= real_decl_result
;
6647 /* If returning a structure, arrange to return the address of the value
6648 in a place where debuggers expect to find it.
6650 If returning a structure PCC style,
6651 the caller also depends on this value.
6652 And current_function_returns_pcc_struct is not necessarily set. */
6653 if (current_function_returns_struct
6654 || current_function_returns_pcc_struct
)
6656 rtx value_address
= XEXP (DECL_RTL (DECL_RESULT (current_function_decl
)), 0);
6657 tree type
= TREE_TYPE (DECL_RESULT (current_function_decl
));
6658 #ifdef FUNCTION_OUTGOING_VALUE
6660 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type
),
6661 current_function_decl
);
6664 = FUNCTION_VALUE (build_pointer_type (type
),
6665 current_function_decl
);
6668 /* Mark this as a function return value so integrate will delete the
6669 assignment and USE below when inlining this function. */
6670 REG_FUNCTION_VALUE_P (outgoing
) = 1;
6672 emit_move_insn (outgoing
, value_address
);
6675 /* ??? This should no longer be necessary since stupid is no longer with
6676 us, but there are some parts of the compiler (eg reload_combine, and
6677 sh mach_dep_reorg) that still try and compute their own lifetime info
6678 instead of using the general framework. */
6679 use_return_register ();
6681 /* If this is an implementation of __throw, do what's necessary to
6682 communicate between __builtin_eh_return and the epilogue. */
6683 expand_eh_return ();
6685 /* Output a return insn if we are using one.
6686 Otherwise, let the rtl chain end here, to drop through
6687 into the epilogue. */
6692 emit_jump_insn (gen_return ());
6697 /* Fix up any gotos that jumped out to the outermost
6698 binding level of the function.
6699 Must follow emitting RETURN_LABEL. */
6701 /* If you have any cleanups to do at this point,
6702 and they need to create temporary variables,
6703 then you will lose. */
6704 expand_fixups (get_insns ());
6707 /* Extend a vector that records the INSN_UIDs of INSNS (either a
6708 sequence or a single insn). */
6711 record_insns (insns
, vecp
)
6715 if (GET_CODE (insns
) == SEQUENCE
)
6717 int len
= XVECLEN (insns
, 0);
6718 int i
= VARRAY_SIZE (*vecp
);
6720 VARRAY_GROW (*vecp
, i
+ len
);
6723 VARRAY_INT (*vecp
, i
) = INSN_UID (XVECEXP (insns
, 0, len
));
6729 int i
= VARRAY_SIZE (*vecp
);
6730 VARRAY_GROW (*vecp
, i
+ 1);
6731 VARRAY_INT (*vecp
, i
) = INSN_UID (insns
);
6735 /* Determine how many INSN_UIDs in VEC are part of INSN. */
6738 contains (insn
, vec
)
6744 if (GET_CODE (insn
) == INSN
6745 && GET_CODE (PATTERN (insn
)) == SEQUENCE
)
6748 for (i
= XVECLEN (PATTERN (insn
), 0) - 1; i
>= 0; i
--)
6749 for (j
= VARRAY_SIZE (vec
) - 1; j
>= 0; --j
)
6750 if (INSN_UID (XVECEXP (PATTERN (insn
), 0, i
)) == VARRAY_INT (vec
, j
))
6756 for (j
= VARRAY_SIZE (vec
) - 1; j
>= 0; --j
)
6757 if (INSN_UID (insn
) == VARRAY_INT (vec
, j
))
6764 prologue_epilogue_contains (insn
)
6767 if (contains (insn
, prologue
))
6769 if (contains (insn
, epilogue
))
6775 sibcall_epilogue_contains (insn
)
6778 if (sibcall_epilogue
)
6779 return contains (insn
, sibcall_epilogue
);
6784 /* Insert gen_return at the end of block BB. This also means updating
6785 block_for_insn appropriately. */
6788 emit_return_into_block (bb
)
6793 end
= emit_jump_insn_after (gen_return (), bb
->end
);
6794 p
= NEXT_INSN (bb
->end
);
6797 set_block_for_insn (p
, bb
);
6804 #endif /* HAVE_return */
6806 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
6807 this into place with notes indicating where the prologue ends and where
6808 the epilogue begins. Update the basic block information when possible. */
6811 thread_prologue_and_epilogue_insns (f
)
6812 rtx f ATTRIBUTE_UNUSED
;
6818 #ifdef HAVE_prologue
6824 seq
= gen_prologue();
6827 /* Retain a map of the prologue insns. */
6828 if (GET_CODE (seq
) != SEQUENCE
)
6830 record_insns (seq
, &prologue
);
6831 emit_note (NULL
, NOTE_INSN_PROLOGUE_END
);
6833 /* GDB handles `break f' by setting a breakpoint on the first
6834 line note *after* the prologue. That means that we should
6835 insert a line note here; otherwise, if the next line note
6836 comes part way into the next block, GDB will skip all the way
6838 insn
= next_nonnote_insn (f
);
6841 if (GET_CODE (insn
) == NOTE
6842 && NOTE_LINE_NUMBER (insn
) >= 0)
6844 emit_line_note_force (NOTE_SOURCE_FILE (insn
),
6845 NOTE_LINE_NUMBER (insn
));
6849 insn
= PREV_INSN (insn
);
6852 seq
= gen_sequence ();
6855 /* If optimization is off, and perhaps in an empty function,
6856 the entry block will have no successors. */
6857 if (ENTRY_BLOCK_PTR
->succ
)
6859 /* Can't deal with multiple successsors of the entry block. */
6860 if (ENTRY_BLOCK_PTR
->succ
->succ_next
)
6863 insert_insn_on_edge (seq
, ENTRY_BLOCK_PTR
->succ
);
6867 emit_insn_after (seq
, f
);
6871 /* If the exit block has no non-fake predecessors, we don't need
6873 for (e
= EXIT_BLOCK_PTR
->pred
; e
; e
= e
->pred_next
)
6874 if ((e
->flags
& EDGE_FAKE
) == 0)
6880 if (optimize
&& HAVE_return
)
6882 /* If we're allowed to generate a simple return instruction,
6883 then by definition we don't need a full epilogue. Examine
6884 the block that falls through to EXIT. If it does not
6885 contain any code, examine its predecessors and try to
6886 emit (conditional) return instructions. */
6892 for (e
= EXIT_BLOCK_PTR
->pred
; e
; e
= e
->pred_next
)
6893 if (e
->flags
& EDGE_FALLTHRU
)
6899 /* Verify that there are no active instructions in the last block. */
6901 while (label
&& GET_CODE (label
) != CODE_LABEL
)
6903 if (active_insn_p (label
))
6905 label
= PREV_INSN (label
);
6908 if (last
->head
== label
&& GET_CODE (label
) == CODE_LABEL
)
6910 for (e
= last
->pred
; e
; e
= e_next
)
6912 basic_block bb
= e
->src
;
6915 e_next
= e
->pred_next
;
6916 if (bb
== ENTRY_BLOCK_PTR
)
6920 if ((GET_CODE (jump
) != JUMP_INSN
) || JUMP_LABEL (jump
) != label
)
6923 /* If we have an unconditional jump, we can replace that
6924 with a simple return instruction. */
6925 if (simplejump_p (jump
))
6927 emit_return_into_block (bb
);
6928 flow_delete_insn (jump
);
6931 /* If we have a conditional jump, we can try to replace
6932 that with a conditional return instruction. */
6933 else if (condjump_p (jump
))
6937 ret
= SET_SRC (PATTERN (jump
));
6938 if (GET_CODE (XEXP (ret
, 1)) == LABEL_REF
)
6939 loc
= &XEXP (ret
, 1);
6941 loc
= &XEXP (ret
, 2);
6942 ret
= gen_rtx_RETURN (VOIDmode
);
6944 if (! validate_change (jump
, loc
, ret
, 0))
6946 if (JUMP_LABEL (jump
))
6947 LABEL_NUSES (JUMP_LABEL (jump
))--;
6949 /* If this block has only one successor, it both jumps
6950 and falls through to the fallthru block, so we can't
6952 if (bb
->succ
->succ_next
== NULL
)
6958 /* Fix up the CFG for the successful change we just made. */
6960 make_edge (NULL
, bb
, EXIT_BLOCK_PTR
, 0);
6963 /* Emit a return insn for the exit fallthru block. Whether
6964 this is still reachable will be determined later. */
6966 emit_barrier_after (last
->end
);
6967 emit_return_into_block (last
);
6971 /* The exit block wasn't empty. We have to use insert_insn_on_edge,
6972 as it may be the exit block can go elsewhere as well
6975 emit_jump_insn (gen_return ());
6976 seq
= gen_sequence ();
6978 insert_insn_on_edge (seq
, e
);
6984 #ifdef HAVE_epilogue
6987 /* Find the edge that falls through to EXIT. Other edges may exist
6988 due to RETURN instructions, but those don't need epilogues.
6989 There really shouldn't be a mixture -- either all should have
6990 been converted or none, however... */
6992 for (e
= EXIT_BLOCK_PTR
->pred
; e
; e
= e
->pred_next
)
6993 if (e
->flags
& EDGE_FALLTHRU
)
6999 emit_note (NULL
, NOTE_INSN_EPILOGUE_BEG
);
7001 seq
= gen_epilogue ();
7002 emit_jump_insn (seq
);
7004 /* Retain a map of the epilogue insns. */
7005 if (GET_CODE (seq
) != SEQUENCE
)
7007 record_insns (seq
, &epilogue
);
7009 seq
= gen_sequence ();
7012 insert_insn_on_edge (seq
, e
);
7019 commit_edge_insertions ();
7021 #ifdef HAVE_sibcall_epilogue
7022 /* Emit sibling epilogues before any sibling call sites. */
7023 for (e
= EXIT_BLOCK_PTR
->pred
; e
; e
= e
->pred_next
)
7025 basic_block bb
= e
->src
;
7029 if (GET_CODE (insn
) != CALL_INSN
7030 || ! SIBLING_CALL_P (insn
))
7034 seq
= gen_sibcall_epilogue ();
7037 i
= PREV_INSN (insn
);
7038 emit_insn_before (seq
, insn
);
7040 /* Update the UID to basic block map. */
7041 for (i
= NEXT_INSN (i
); i
!= insn
; i
= NEXT_INSN (i
))
7042 set_block_for_insn (i
, bb
);
7044 /* Retain a map of the epilogue insns. Used in life analysis to
7045 avoid getting rid of sibcall epilogue insns. */
7046 record_insns (seq
, &sibcall_epilogue
);
7051 /* Reposition the prologue-end and epilogue-begin notes after instruction
7052 scheduling and delayed branch scheduling. */
7055 reposition_prologue_and_epilogue_notes (f
)
7056 rtx f ATTRIBUTE_UNUSED
;
7058 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7061 if ((len
= VARRAY_SIZE (prologue
)) > 0)
7063 register rtx insn
, note
= 0;
7065 /* Scan from the beginning until we reach the last prologue insn.
7066 We apparently can't depend on basic_block_{head,end} after
7068 for (insn
= f
; len
&& insn
; insn
= NEXT_INSN (insn
))
7070 if (GET_CODE (insn
) == NOTE
)
7072 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_PROLOGUE_END
)
7075 else if ((len
-= contains (insn
, prologue
)) == 0)
7078 /* Find the prologue-end note if we haven't already, and
7079 move it to just after the last prologue insn. */
7082 for (note
= insn
; (note
= NEXT_INSN (note
));)
7083 if (GET_CODE (note
) == NOTE
7084 && NOTE_LINE_NUMBER (note
) == NOTE_INSN_PROLOGUE_END
)
7088 next
= NEXT_INSN (note
);
7090 /* Whether or not we can depend on BLOCK_HEAD,
7091 attempt to keep it up-to-date. */
7092 if (BLOCK_HEAD (0) == note
)
7093 BLOCK_HEAD (0) = next
;
7096 add_insn_after (note
, insn
);
7101 if ((len
= VARRAY_SIZE (epilogue
)) > 0)
7103 register rtx insn
, note
= 0;
7105 /* Scan from the end until we reach the first epilogue insn.
7106 We apparently can't depend on basic_block_{head,end} after
7108 for (insn
= get_last_insn (); len
&& insn
; insn
= PREV_INSN (insn
))
7110 if (GET_CODE (insn
) == NOTE
)
7112 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_EPILOGUE_BEG
)
7115 else if ((len
-= contains (insn
, epilogue
)) == 0)
7117 /* Find the epilogue-begin note if we haven't already, and
7118 move it to just before the first epilogue insn. */
7121 for (note
= insn
; (note
= PREV_INSN (note
));)
7122 if (GET_CODE (note
) == NOTE
7123 && NOTE_LINE_NUMBER (note
) == NOTE_INSN_EPILOGUE_BEG
)
7127 /* Whether or not we can depend on BLOCK_HEAD,
7128 attempt to keep it up-to-date. */
7130 && BLOCK_HEAD (n_basic_blocks
-1) == insn
)
7131 BLOCK_HEAD (n_basic_blocks
-1) = note
;
7134 add_insn_before (note
, insn
);
7138 #endif /* HAVE_prologue or HAVE_epilogue */
7141 /* Mark T for GC. */
7145 struct temp_slot
*t
;
7149 ggc_mark_rtx (t
->slot
);
7150 ggc_mark_rtx (t
->address
);
7151 ggc_mark_tree (t
->rtl_expr
);
7157 /* Mark P for GC. */
7160 mark_function_status (p
)
7169 ggc_mark_rtx (p
->arg_offset_rtx
);
7171 if (p
->x_parm_reg_stack_loc
)
7172 for (i
= p
->x_max_parm_reg
, r
= p
->x_parm_reg_stack_loc
;
7176 ggc_mark_rtx (p
->return_rtx
);
7177 ggc_mark_rtx (p
->x_cleanup_label
);
7178 ggc_mark_rtx (p
->x_return_label
);
7179 ggc_mark_rtx (p
->x_save_expr_regs
);
7180 ggc_mark_rtx (p
->x_stack_slot_list
);
7181 ggc_mark_rtx (p
->x_parm_birth_insn
);
7182 ggc_mark_rtx (p
->x_tail_recursion_label
);
7183 ggc_mark_rtx (p
->x_tail_recursion_reentry
);
7184 ggc_mark_rtx (p
->internal_arg_pointer
);
7185 ggc_mark_rtx (p
->x_arg_pointer_save_area
);
7186 ggc_mark_tree (p
->x_rtl_expr_chain
);
7187 ggc_mark_rtx (p
->x_last_parm_insn
);
7188 ggc_mark_tree (p
->x_context_display
);
7189 ggc_mark_tree (p
->x_trampoline_list
);
7190 ggc_mark_rtx (p
->epilogue_delay_list
);
7192 mark_temp_slot (p
->x_temp_slots
);
7195 struct var_refs_queue
*q
= p
->fixup_var_refs_queue
;
7198 ggc_mark_rtx (q
->modified
);
7203 ggc_mark_rtx (p
->x_nonlocal_goto_handler_slots
);
7204 ggc_mark_rtx (p
->x_nonlocal_goto_handler_labels
);
7205 ggc_mark_rtx (p
->x_nonlocal_goto_stack_level
);
7206 ggc_mark_tree (p
->x_nonlocal_labels
);
7209 /* Mark the function chain ARG (which is really a struct function **)
7213 mark_function_chain (arg
)
7216 struct function
*f
= *(struct function
**) arg
;
7218 for (; f
; f
= f
->next_global
)
7220 ggc_mark_tree (f
->decl
);
7222 mark_function_status (f
);
7223 mark_eh_status (f
->eh
);
7224 mark_stmt_status (f
->stmt
);
7225 mark_expr_status (f
->expr
);
7226 mark_emit_status (f
->emit
);
7227 mark_varasm_status (f
->varasm
);
7229 if (mark_machine_status
)
7230 (*mark_machine_status
) (f
);
7231 if (mark_lang_status
)
7232 (*mark_lang_status
) (f
);
7234 if (f
->original_arg_vector
)
7235 ggc_mark_rtvec ((rtvec
) f
->original_arg_vector
);
7236 if (f
->original_decl_initial
)
7237 ggc_mark_tree (f
->original_decl_initial
);
7241 /* Called once, at initialization, to initialize function.c. */
7244 init_function_once ()
7246 ggc_add_root (&all_functions
, 1, sizeof all_functions
,
7247 mark_function_chain
);
7249 VARRAY_INT_INIT (prologue
, 0, "prologue");
7250 VARRAY_INT_INIT (epilogue
, 0, "epilogue");
7251 VARRAY_INT_INIT (sibcall_epilogue
, 0, "sibcall_epilogue");