1 /* Expands front end tree to back end RTL for GNU C-Compiler
2 Copyright (C) 1987, 88, 89, 91-97, 1998 Free Software Foundation, Inc.
4 This file is part of GNU CC.
6 GNU CC is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 GNU CC is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GNU CC; see the file COPYING. If not, write to
18 the Free Software Foundation, 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
22 /* This file handles the generation of rtl code from tree structure
23 at the level of the function as a whole.
24 It creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 `expand_function_start' is called at the beginning of a function,
28 before the function body is parsed, and `expand_function_end' is
29 called after parsing the body.
31 Call `assign_stack_local' to allocate a stack slot for a local variable.
32 This is usually done during the RTL generation for the function body,
33 but it can also be done in the reload pass when a pseudo-register does
34 not get a hard register.
36 Call `put_var_into_stack' when you learn, belatedly, that a variable
37 previously given a pseudo-register must in fact go in the stack.
38 This function changes the DECL_RTL to be a stack slot instead of a reg
39 then scans all the RTL instructions so far generated to correct them. */
48 #include "insn-flags.h"
50 #include "insn-codes.h"
52 #include "hard-reg-set.h"
53 #include "insn-config.h"
56 #include "basic-block.h"
60 #ifndef TRAMPOLINE_ALIGNMENT
61 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
64 /* Some systems use __main in a way incompatible with its use in gcc, in these
65 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
66 give the same symbol without quotes for an alternative entry point. You
67 must define both, or neither. */
69 #define NAME__MAIN "__main"
70 #define SYMBOL__MAIN __main
73 /* Round a value to the lowest integer less than it that is a multiple of
74 the required alignment. Avoid using division in case the value is
75 negative. Assume the alignment is a power of two. */
76 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
78 /* Similar, but round to the next highest integer that meets the
80 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
82 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
83 during rtl generation. If they are different register numbers, this is
84 always true. It may also be true if
85 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
86 generation. See fix_lexical_addr for details. */
88 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
89 #define NEED_SEPARATE_AP
92 /* Number of bytes of args popped by function being compiled on its return.
93 Zero if no bytes are to be popped.
94 May affect compilation of return insn or of function epilogue. */
96 int current_function_pops_args
;
98 /* Nonzero if function being compiled needs to be given an address
99 where the value should be stored. */
101 int current_function_returns_struct
;
103 /* Nonzero if function being compiled needs to
104 return the address of where it has put a structure value. */
106 int current_function_returns_pcc_struct
;
108 /* Nonzero if function being compiled needs to be passed a static chain. */
110 int current_function_needs_context
;
112 /* Nonzero if function being compiled can call setjmp. */
114 int current_function_calls_setjmp
;
116 /* Nonzero if function being compiled can call longjmp. */
118 int current_function_calls_longjmp
;
120 /* Nonzero if function being compiled receives nonlocal gotos
121 from nested functions. */
123 int current_function_has_nonlocal_label
;
125 /* Nonzero if function being compiled has nonlocal gotos to parent
128 int current_function_has_nonlocal_goto
;
130 /* Nonzero if this function has a computed goto.
132 It is computed during find_basic_blocks or during stupid life
135 int current_function_has_computed_jump
;
137 /* Nonzero if function being compiled contains nested functions. */
139 int current_function_contains_functions
;
141 /* Nonzero if the current function is a thunk (a lightweight function that
142 just adjusts one of its arguments and forwards to another function), so
143 we should try to cut corners where we can. */
144 int current_function_is_thunk
;
146 /* Nonzero if function being compiled can call alloca,
147 either as a subroutine or builtin. */
149 int current_function_calls_alloca
;
151 /* Nonzero if the current function returns a pointer type */
153 int current_function_returns_pointer
;
155 /* If some insns can be deferred to the delay slots of the epilogue, the
156 delay list for them is recorded here. */
158 rtx current_function_epilogue_delay_list
;
160 /* If function's args have a fixed size, this is that size, in bytes.
162 May affect compilation of return insn or of function epilogue. */
164 int current_function_args_size
;
166 /* # bytes the prologue should push and pretend that the caller pushed them.
167 The prologue must do this, but only if parms can be passed in registers. */
169 int current_function_pretend_args_size
;
171 /* # of bytes of outgoing arguments. If ACCUMULATE_OUTGOING_ARGS is
172 defined, the needed space is pushed by the prologue. */
174 int current_function_outgoing_args_size
;
176 /* This is the offset from the arg pointer to the place where the first
177 anonymous arg can be found, if there is one. */
179 rtx current_function_arg_offset_rtx
;
181 /* Nonzero if current function uses varargs.h or equivalent.
182 Zero for functions that use stdarg.h. */
184 int current_function_varargs
;
186 /* Nonzero if current function uses stdarg.h or equivalent.
187 Zero for functions that use varargs.h. */
189 int current_function_stdarg
;
191 /* Quantities of various kinds of registers
192 used for the current function's args. */
194 CUMULATIVE_ARGS current_function_args_info
;
196 /* Name of function now being compiled. */
198 char *current_function_name
;
200 /* If non-zero, an RTL expression for the location at which the current
201 function returns its result. If the current function returns its
202 result in a register, current_function_return_rtx will always be
203 the hard register containing the result. */
205 rtx current_function_return_rtx
;
207 /* Nonzero if the current function uses the constant pool. */
209 int current_function_uses_const_pool
;
211 /* Nonzero if the current function uses pic_offset_table_rtx. */
212 int current_function_uses_pic_offset_table
;
214 /* The arg pointer hard register, or the pseudo into which it was copied. */
215 rtx current_function_internal_arg_pointer
;
217 /* Language-specific reason why the current function cannot be made inline. */
218 char *current_function_cannot_inline
;
220 /* Nonzero if instrumentation calls for function entry and exit should be
222 int current_function_instrument_entry_exit
;
224 /* The FUNCTION_DECL for an inline function currently being expanded. */
225 tree inline_function_decl
;
227 /* Number of function calls seen so far in current function. */
229 int function_call_count
;
231 /* List (chain of TREE_LIST) of LABEL_DECLs for all nonlocal labels
232 (labels to which there can be nonlocal gotos from nested functions)
235 tree nonlocal_labels
;
237 /* RTX for stack slot that holds the current handler for nonlocal gotos.
238 Zero when function does not have nonlocal labels. */
240 rtx nonlocal_goto_handler_slot
;
242 /* RTX for stack slot that holds the stack pointer value to restore
244 Zero when function does not have nonlocal labels. */
246 rtx nonlocal_goto_stack_level
;
248 /* Label that will go on parm cleanup code, if any.
249 Jumping to this label runs cleanup code for parameters, if
250 such code must be run. Following this code is the logical return label. */
254 /* Label that will go on function epilogue.
255 Jumping to this label serves as a "return" instruction
256 on machines which require execution of the epilogue on all returns. */
260 /* List (chain of EXPR_LISTs) of pseudo-regs of SAVE_EXPRs.
261 So we can mark them all live at the end of the function, if nonopt. */
264 /* List (chain of EXPR_LISTs) of all stack slots in this function.
265 Made for the sake of unshare_all_rtl. */
268 /* Chain of all RTL_EXPRs that have insns in them. */
271 /* Label to jump back to for tail recursion, or 0 if we have
272 not yet needed one for this function. */
273 rtx tail_recursion_label
;
275 /* Place after which to insert the tail_recursion_label if we need one. */
276 rtx tail_recursion_reentry
;
278 /* Location at which to save the argument pointer if it will need to be
279 referenced. There are two cases where this is done: if nonlocal gotos
280 exist, or if vars stored at an offset from the argument pointer will be
281 needed by inner routines. */
283 rtx arg_pointer_save_area
;
285 /* Offset to end of allocated area of stack frame.
286 If stack grows down, this is the address of the last stack slot allocated.
287 If stack grows up, this is the address for the next slot. */
288 HOST_WIDE_INT frame_offset
;
290 /* List (chain of TREE_LISTs) of static chains for containing functions.
291 Each link has a FUNCTION_DECL in the TREE_PURPOSE and a reg rtx
292 in an RTL_EXPR in the TREE_VALUE. */
293 static tree context_display
;
295 /* List (chain of TREE_LISTs) of trampolines for nested functions.
296 The trampoline sets up the static chain and jumps to the function.
297 We supply the trampoline's address when the function's address is requested.
299 Each link has a FUNCTION_DECL in the TREE_PURPOSE and a reg rtx
300 in an RTL_EXPR in the TREE_VALUE. */
301 static tree trampoline_list
;
303 /* Insn after which register parms and SAVE_EXPRs are born, if nonopt. */
304 static rtx parm_birth_insn
;
307 /* Nonzero if a stack slot has been generated whose address is not
308 actually valid. It means that the generated rtl must all be scanned
309 to detect and correct the invalid addresses where they occur. */
310 static int invalid_stack_slot
;
313 /* Last insn of those whose job was to put parms into their nominal homes. */
314 static rtx last_parm_insn
;
316 /* 1 + last pseudo register number possibly used for loading a copy
317 of a parameter of this function. */
320 /* Vector indexed by REGNO, containing location on stack in which
321 to put the parm which is nominally in pseudo register REGNO,
322 if we discover that that parm must go in the stack. The highest
323 element in this vector is one less than MAX_PARM_REG, above. */
324 rtx
*parm_reg_stack_loc
;
326 /* Nonzero once virtual register instantiation has been done.
327 assign_stack_local uses frame_pointer_rtx when this is nonzero. */
328 static int virtuals_instantiated
;
330 /* These variables hold pointers to functions to
331 save and restore machine-specific data,
332 in push_function_context and pop_function_context. */
333 void (*save_machine_status
) PROTO((struct function
*));
334 void (*restore_machine_status
) PROTO((struct function
*));
336 /* Nonzero if we need to distinguish between the return value of this function
337 and the return value of a function called by this function. This helps
340 extern int rtx_equal_function_value_matters
;
341 extern tree sequence_rtl_expr
;
343 /* In order to evaluate some expressions, such as function calls returning
344 structures in memory, we need to temporarily allocate stack locations.
345 We record each allocated temporary in the following structure.
347 Associated with each temporary slot is a nesting level. When we pop up
348 one level, all temporaries associated with the previous level are freed.
349 Normally, all temporaries are freed after the execution of the statement
350 in which they were created. However, if we are inside a ({...}) grouping,
351 the result may be in a temporary and hence must be preserved. If the
352 result could be in a temporary, we preserve it if we can determine which
353 one it is in. If we cannot determine which temporary may contain the
354 result, all temporaries are preserved. A temporary is preserved by
355 pretending it was allocated at the previous nesting level.
357 Automatic variables are also assigned temporary slots, at the nesting
358 level where they are defined. They are marked a "kept" so that
359 free_temp_slots will not free them. */
363 /* Points to next temporary slot. */
364 struct temp_slot
*next
;
365 /* The rtx to used to reference the slot. */
367 /* The rtx used to represent the address if not the address of the
368 slot above. May be an EXPR_LIST if multiple addresses exist. */
370 /* The size, in units, of the slot. */
372 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
374 /* Non-zero if this temporary is currently in use. */
376 /* Non-zero if this temporary has its address taken. */
378 /* Nesting level at which this slot is being used. */
380 /* Non-zero if this should survive a call to free_temp_slots. */
382 /* The offset of the slot from the frame_pointer, including extra space
383 for alignment. This info is for combine_temp_slots. */
384 HOST_WIDE_INT base_offset
;
385 /* The size of the slot, including extra space for alignment. This
386 info is for combine_temp_slots. */
387 HOST_WIDE_INT full_size
;
390 /* List of all temporaries allocated, both available and in use. */
392 struct temp_slot
*temp_slots
;
394 /* Current nesting level for temporaries. */
398 /* Current nesting level for variables in a block. */
400 int var_temp_slot_level
;
402 /* When temporaries are created by TARGET_EXPRs, they are created at
403 this level of temp_slot_level, so that they can remain allocated
404 until no longer needed. CLEANUP_POINT_EXPRs define the lifetime
406 int target_temp_slot_level
;
408 /* This structure is used to record MEMs or pseudos used to replace VAR, any
409 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
410 maintain this list in case two operands of an insn were required to match;
411 in that case we must ensure we use the same replacement. */
413 struct fixup_replacement
417 struct fixup_replacement
*next
;
420 /* Forward declarations. */
422 static rtx assign_outer_stack_local
PROTO ((enum machine_mode
, HOST_WIDE_INT
,
423 int, struct function
*));
424 static struct temp_slot
*find_temp_slot_from_address
PROTO((rtx
));
425 static void put_reg_into_stack
PROTO((struct function
*, rtx
, tree
,
426 enum machine_mode
, enum machine_mode
,
428 static void fixup_var_refs
PROTO((rtx
, enum machine_mode
, int));
429 static struct fixup_replacement
430 *find_fixup_replacement
PROTO((struct fixup_replacement
**, rtx
));
431 static void fixup_var_refs_insns
PROTO((rtx
, enum machine_mode
, int,
433 static void fixup_var_refs_1
PROTO((rtx
, enum machine_mode
, rtx
*, rtx
,
434 struct fixup_replacement
**));
435 static rtx fixup_memory_subreg
PROTO((rtx
, rtx
, int));
436 static rtx walk_fixup_memory_subreg
PROTO((rtx
, rtx
, int));
437 static rtx fixup_stack_1
PROTO((rtx
, rtx
));
438 static void optimize_bit_field
PROTO((rtx
, rtx
, rtx
*));
439 static void instantiate_decls
PROTO((tree
, int));
440 static void instantiate_decls_1
PROTO((tree
, int));
441 static void instantiate_decl
PROTO((rtx
, int, int));
442 static int instantiate_virtual_regs_1
PROTO((rtx
*, rtx
, int));
443 static void delete_handlers
PROTO((void));
444 static void pad_to_arg_alignment
PROTO((struct args_size
*, int));
445 #ifndef ARGS_GROW_DOWNWARD
446 static void pad_below
PROTO((struct args_size
*, enum machine_mode
,
449 #ifdef ARGS_GROW_DOWNWARD
450 static tree round_down
PROTO((tree
, int));
452 static rtx round_trampoline_addr
PROTO((rtx
));
453 static tree blocks_nreverse
PROTO((tree
));
454 static int all_blocks
PROTO((tree
, tree
*));
455 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
456 static int *record_insns
PROTO((rtx
));
457 static int contains
PROTO((rtx
, int *));
458 #endif /* HAVE_prologue || HAVE_epilogue */
459 static void put_addressof_into_stack
PROTO((rtx
));
460 static void purge_addressof_1
PROTO((rtx
*, rtx
, int));
462 /* Pointer to chain of `struct function' for containing functions. */
463 struct function
*outer_function_chain
;
465 /* Given a function decl for a containing function,
466 return the `struct function' for it. */
469 find_function_data (decl
)
474 for (p
= outer_function_chain
; p
; p
= p
->next
)
481 /* Save the current context for compilation of a nested function.
482 This is called from language-specific code.
483 The caller is responsible for saving any language-specific status,
484 since this function knows only about language-independent variables. */
487 push_function_context_to (context
)
490 struct function
*p
= (struct function
*) xmalloc (sizeof (struct function
));
492 p
->next
= outer_function_chain
;
493 outer_function_chain
= p
;
495 p
->name
= current_function_name
;
496 p
->decl
= current_function_decl
;
497 p
->pops_args
= current_function_pops_args
;
498 p
->returns_struct
= current_function_returns_struct
;
499 p
->returns_pcc_struct
= current_function_returns_pcc_struct
;
500 p
->returns_pointer
= current_function_returns_pointer
;
501 p
->needs_context
= current_function_needs_context
;
502 p
->calls_setjmp
= current_function_calls_setjmp
;
503 p
->calls_longjmp
= current_function_calls_longjmp
;
504 p
->calls_alloca
= current_function_calls_alloca
;
505 p
->has_nonlocal_label
= current_function_has_nonlocal_label
;
506 p
->has_nonlocal_goto
= current_function_has_nonlocal_goto
;
507 p
->contains_functions
= current_function_contains_functions
;
508 p
->is_thunk
= current_function_is_thunk
;
509 p
->args_size
= current_function_args_size
;
510 p
->pretend_args_size
= current_function_pretend_args_size
;
511 p
->arg_offset_rtx
= current_function_arg_offset_rtx
;
512 p
->varargs
= current_function_varargs
;
513 p
->stdarg
= current_function_stdarg
;
514 p
->uses_const_pool
= current_function_uses_const_pool
;
515 p
->uses_pic_offset_table
= current_function_uses_pic_offset_table
;
516 p
->internal_arg_pointer
= current_function_internal_arg_pointer
;
517 p
->cannot_inline
= current_function_cannot_inline
;
518 p
->max_parm_reg
= max_parm_reg
;
519 p
->parm_reg_stack_loc
= parm_reg_stack_loc
;
520 p
->outgoing_args_size
= current_function_outgoing_args_size
;
521 p
->return_rtx
= current_function_return_rtx
;
522 p
->nonlocal_goto_handler_slot
= nonlocal_goto_handler_slot
;
523 p
->nonlocal_goto_stack_level
= nonlocal_goto_stack_level
;
524 p
->nonlocal_labels
= nonlocal_labels
;
525 p
->cleanup_label
= cleanup_label
;
526 p
->return_label
= return_label
;
527 p
->save_expr_regs
= save_expr_regs
;
528 p
->stack_slot_list
= stack_slot_list
;
529 p
->parm_birth_insn
= parm_birth_insn
;
530 p
->frame_offset
= frame_offset
;
531 p
->tail_recursion_label
= tail_recursion_label
;
532 p
->tail_recursion_reentry
= tail_recursion_reentry
;
533 p
->arg_pointer_save_area
= arg_pointer_save_area
;
534 p
->rtl_expr_chain
= rtl_expr_chain
;
535 p
->last_parm_insn
= last_parm_insn
;
536 p
->context_display
= context_display
;
537 p
->trampoline_list
= trampoline_list
;
538 p
->function_call_count
= function_call_count
;
539 p
->temp_slots
= temp_slots
;
540 p
->temp_slot_level
= temp_slot_level
;
541 p
->target_temp_slot_level
= target_temp_slot_level
;
542 p
->var_temp_slot_level
= var_temp_slot_level
;
543 p
->fixup_var_refs_queue
= 0;
544 p
->epilogue_delay_list
= current_function_epilogue_delay_list
;
545 p
->args_info
= current_function_args_info
;
546 p
->instrument_entry_exit
= current_function_instrument_entry_exit
;
548 save_tree_status (p
, context
);
549 save_storage_status (p
);
550 save_emit_status (p
);
551 save_expr_status (p
);
552 save_stmt_status (p
);
553 save_varasm_status (p
, context
);
554 if (save_machine_status
)
555 (*save_machine_status
) (p
);
559 push_function_context ()
561 push_function_context_to (current_function_decl
);
564 /* Restore the last saved context, at the end of a nested function.
565 This function is called from language-specific code. */
568 pop_function_context_from (context
)
571 struct function
*p
= outer_function_chain
;
572 struct var_refs_queue
*queue
;
574 outer_function_chain
= p
->next
;
576 current_function_contains_functions
577 = p
->contains_functions
|| p
->inline_obstacks
578 || context
== current_function_decl
;
579 current_function_name
= p
->name
;
580 current_function_decl
= p
->decl
;
581 current_function_pops_args
= p
->pops_args
;
582 current_function_returns_struct
= p
->returns_struct
;
583 current_function_returns_pcc_struct
= p
->returns_pcc_struct
;
584 current_function_returns_pointer
= p
->returns_pointer
;
585 current_function_needs_context
= p
->needs_context
;
586 current_function_calls_setjmp
= p
->calls_setjmp
;
587 current_function_calls_longjmp
= p
->calls_longjmp
;
588 current_function_calls_alloca
= p
->calls_alloca
;
589 current_function_has_nonlocal_label
= p
->has_nonlocal_label
;
590 current_function_has_nonlocal_goto
= p
->has_nonlocal_goto
;
591 current_function_is_thunk
= p
->is_thunk
;
592 current_function_args_size
= p
->args_size
;
593 current_function_pretend_args_size
= p
->pretend_args_size
;
594 current_function_arg_offset_rtx
= p
->arg_offset_rtx
;
595 current_function_varargs
= p
->varargs
;
596 current_function_stdarg
= p
->stdarg
;
597 current_function_uses_const_pool
= p
->uses_const_pool
;
598 current_function_uses_pic_offset_table
= p
->uses_pic_offset_table
;
599 current_function_internal_arg_pointer
= p
->internal_arg_pointer
;
600 current_function_cannot_inline
= p
->cannot_inline
;
601 max_parm_reg
= p
->max_parm_reg
;
602 parm_reg_stack_loc
= p
->parm_reg_stack_loc
;
603 current_function_outgoing_args_size
= p
->outgoing_args_size
;
604 current_function_return_rtx
= p
->return_rtx
;
605 nonlocal_goto_handler_slot
= p
->nonlocal_goto_handler_slot
;
606 nonlocal_goto_stack_level
= p
->nonlocal_goto_stack_level
;
607 nonlocal_labels
= p
->nonlocal_labels
;
608 cleanup_label
= p
->cleanup_label
;
609 return_label
= p
->return_label
;
610 save_expr_regs
= p
->save_expr_regs
;
611 stack_slot_list
= p
->stack_slot_list
;
612 parm_birth_insn
= p
->parm_birth_insn
;
613 frame_offset
= p
->frame_offset
;
614 tail_recursion_label
= p
->tail_recursion_label
;
615 tail_recursion_reentry
= p
->tail_recursion_reentry
;
616 arg_pointer_save_area
= p
->arg_pointer_save_area
;
617 rtl_expr_chain
= p
->rtl_expr_chain
;
618 last_parm_insn
= p
->last_parm_insn
;
619 context_display
= p
->context_display
;
620 trampoline_list
= p
->trampoline_list
;
621 function_call_count
= p
->function_call_count
;
622 temp_slots
= p
->temp_slots
;
623 temp_slot_level
= p
->temp_slot_level
;
624 target_temp_slot_level
= p
->target_temp_slot_level
;
625 var_temp_slot_level
= p
->var_temp_slot_level
;
626 current_function_epilogue_delay_list
= p
->epilogue_delay_list
;
628 current_function_args_info
= p
->args_info
;
629 current_function_instrument_entry_exit
= p
->instrument_entry_exit
;
631 restore_tree_status (p
, context
);
632 restore_storage_status (p
);
633 restore_expr_status (p
);
634 restore_emit_status (p
);
635 restore_stmt_status (p
);
636 restore_varasm_status (p
);
638 if (restore_machine_status
)
639 (*restore_machine_status
) (p
);
641 /* Finish doing put_var_into_stack for any of our variables
642 which became addressable during the nested function. */
643 for (queue
= p
->fixup_var_refs_queue
; queue
; queue
= queue
->next
)
644 fixup_var_refs (queue
->modified
, queue
->promoted_mode
, queue
->unsignedp
);
648 /* Reset variables that have known state during rtx generation. */
649 rtx_equal_function_value_matters
= 1;
650 virtuals_instantiated
= 0;
653 void pop_function_context ()
655 pop_function_context_from (current_function_decl
);
658 /* Allocate fixed slots in the stack frame of the current function. */
660 /* Return size needed for stack frame based on slots so far allocated.
661 This size counts from zero. It is not rounded to STACK_BOUNDARY;
662 the caller may have to do that. */
667 #ifdef FRAME_GROWS_DOWNWARD
668 return -frame_offset
;
674 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
675 with machine mode MODE.
677 ALIGN controls the amount of alignment for the address of the slot:
678 0 means according to MODE,
679 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
680 positive specifies alignment boundary in bits.
682 We do not round to stack_boundary here. */
685 assign_stack_local (mode
, size
, align
)
686 enum machine_mode mode
;
690 register rtx x
, addr
;
691 int bigend_correction
= 0;
696 alignment
= GET_MODE_ALIGNMENT (mode
) / BITS_PER_UNIT
;
698 alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
700 else if (align
== -1)
702 alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
703 size
= CEIL_ROUND (size
, alignment
);
706 alignment
= align
/ BITS_PER_UNIT
;
708 /* Round frame offset to that alignment.
709 We must be careful here, since FRAME_OFFSET might be negative and
710 division with a negative dividend isn't as well defined as we might
711 like. So we instead assume that ALIGNMENT is a power of two and
712 use logical operations which are unambiguous. */
713 #ifdef FRAME_GROWS_DOWNWARD
714 frame_offset
= FLOOR_ROUND (frame_offset
, alignment
);
716 frame_offset
= CEIL_ROUND (frame_offset
, alignment
);
719 /* On a big-endian machine, if we are allocating more space than we will use,
720 use the least significant bytes of those that are allocated. */
721 if (BYTES_BIG_ENDIAN
&& mode
!= BLKmode
)
722 bigend_correction
= size
- GET_MODE_SIZE (mode
);
724 #ifdef FRAME_GROWS_DOWNWARD
725 frame_offset
-= size
;
728 /* If we have already instantiated virtual registers, return the actual
729 address relative to the frame pointer. */
730 if (virtuals_instantiated
)
731 addr
= plus_constant (frame_pointer_rtx
,
732 (frame_offset
+ bigend_correction
733 + STARTING_FRAME_OFFSET
));
735 addr
= plus_constant (virtual_stack_vars_rtx
,
736 frame_offset
+ bigend_correction
);
738 #ifndef FRAME_GROWS_DOWNWARD
739 frame_offset
+= size
;
742 x
= gen_rtx_MEM (mode
, addr
);
744 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, x
, stack_slot_list
);
749 /* Assign a stack slot in a containing function.
750 First three arguments are same as in preceding function.
751 The last argument specifies the function to allocate in. */
754 assign_outer_stack_local (mode
, size
, align
, function
)
755 enum machine_mode mode
;
758 struct function
*function
;
760 register rtx x
, addr
;
761 int bigend_correction
= 0;
764 /* Allocate in the memory associated with the function in whose frame
766 push_obstacks (function
->function_obstack
,
767 function
->function_maybepermanent_obstack
);
771 alignment
= GET_MODE_ALIGNMENT (mode
) / BITS_PER_UNIT
;
773 alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
775 else if (align
== -1)
777 alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
778 size
= CEIL_ROUND (size
, alignment
);
781 alignment
= align
/ BITS_PER_UNIT
;
783 /* Round frame offset to that alignment. */
784 #ifdef FRAME_GROWS_DOWNWARD
785 function
->frame_offset
= FLOOR_ROUND (function
->frame_offset
, alignment
);
787 function
->frame_offset
= CEIL_ROUND (function
->frame_offset
, alignment
);
790 /* On a big-endian machine, if we are allocating more space than we will use,
791 use the least significant bytes of those that are allocated. */
792 if (BYTES_BIG_ENDIAN
&& mode
!= BLKmode
)
793 bigend_correction
= size
- GET_MODE_SIZE (mode
);
795 #ifdef FRAME_GROWS_DOWNWARD
796 function
->frame_offset
-= size
;
798 addr
= plus_constant (virtual_stack_vars_rtx
,
799 function
->frame_offset
+ bigend_correction
);
800 #ifndef FRAME_GROWS_DOWNWARD
801 function
->frame_offset
+= size
;
804 x
= gen_rtx_MEM (mode
, addr
);
806 function
->stack_slot_list
807 = gen_rtx_EXPR_LIST (VOIDmode
, x
, function
->stack_slot_list
);
814 /* Allocate a temporary stack slot and record it for possible later
817 MODE is the machine mode to be given to the returned rtx.
819 SIZE is the size in units of the space required. We do no rounding here
820 since assign_stack_local will do any required rounding.
822 KEEP is 1 if this slot is to be retained after a call to
823 free_temp_slots. Automatic variables for a block are allocated
824 with this flag. KEEP is 2 if we allocate a longer term temporary,
825 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
826 if we are to allocate something at an inner level to be treated as
827 a variable in the block (e.g., a SAVE_EXPR). */
830 assign_stack_temp (mode
, size
, keep
)
831 enum machine_mode mode
;
835 struct temp_slot
*p
, *best_p
= 0;
837 /* If SIZE is -1 it means that somebody tried to allocate a temporary
838 of a variable size. */
842 /* First try to find an available, already-allocated temporary that is the
843 exact size we require. */
844 for (p
= temp_slots
; p
; p
= p
->next
)
845 if (p
->size
== size
&& GET_MODE (p
->slot
) == mode
&& ! p
->in_use
)
848 /* If we didn't find, one, try one that is larger than what we want. We
849 find the smallest such. */
851 for (p
= temp_slots
; p
; p
= p
->next
)
852 if (p
->size
> size
&& GET_MODE (p
->slot
) == mode
&& ! p
->in_use
853 && (best_p
== 0 || best_p
->size
> p
->size
))
856 /* Make our best, if any, the one to use. */
859 /* If there are enough aligned bytes left over, make them into a new
860 temp_slot so that the extra bytes don't get wasted. Do this only
861 for BLKmode slots, so that we can be sure of the alignment. */
862 if (GET_MODE (best_p
->slot
) == BLKmode
)
864 int alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
865 HOST_WIDE_INT rounded_size
= CEIL_ROUND (size
, alignment
);
867 if (best_p
->size
- rounded_size
>= alignment
)
869 p
= (struct temp_slot
*) oballoc (sizeof (struct temp_slot
));
870 p
->in_use
= p
->addr_taken
= 0;
871 p
->size
= best_p
->size
- rounded_size
;
872 p
->base_offset
= best_p
->base_offset
+ rounded_size
;
873 p
->full_size
= best_p
->full_size
- rounded_size
;
874 p
->slot
= gen_rtx_MEM (BLKmode
,
875 plus_constant (XEXP (best_p
->slot
, 0),
879 p
->next
= temp_slots
;
882 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, p
->slot
,
885 best_p
->size
= rounded_size
;
886 best_p
->full_size
= rounded_size
;
893 /* If we still didn't find one, make a new temporary. */
896 HOST_WIDE_INT frame_offset_old
= frame_offset
;
898 p
= (struct temp_slot
*) oballoc (sizeof (struct temp_slot
));
900 /* If the temp slot mode doesn't indicate the alignment,
901 use the largest possible, so no one will be disappointed. */
902 p
->slot
= assign_stack_local (mode
, size
, mode
== BLKmode
? -1 : 0);
904 /* The following slot size computation is necessary because we don't
905 know the actual size of the temporary slot until assign_stack_local
906 has performed all the frame alignment and size rounding for the
907 requested temporary. Note that extra space added for alignment
908 can be either above or below this stack slot depending on which
909 way the frame grows. We include the extra space if and only if it
910 is above this slot. */
911 #ifdef FRAME_GROWS_DOWNWARD
912 p
->size
= frame_offset_old
- frame_offset
;
917 /* Now define the fields used by combine_temp_slots. */
918 #ifdef FRAME_GROWS_DOWNWARD
919 p
->base_offset
= frame_offset
;
920 p
->full_size
= frame_offset_old
- frame_offset
;
922 p
->base_offset
= frame_offset_old
;
923 p
->full_size
= frame_offset
- frame_offset_old
;
926 p
->next
= temp_slots
;
932 p
->rtl_expr
= sequence_rtl_expr
;
936 p
->level
= target_temp_slot_level
;
941 p
->level
= var_temp_slot_level
;
946 p
->level
= temp_slot_level
;
950 /* We may be reusing an old slot, so clear any MEM flags that may have been
952 RTX_UNCHANGING_P (p
->slot
) = 0;
953 MEM_IN_STRUCT_P (p
->slot
) = 0;
957 /* Assign a temporary of given TYPE.
958 KEEP is as for assign_stack_temp.
959 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
960 it is 0 if a register is OK.
961 DONT_PROMOTE is 1 if we should not promote values in register
965 assign_temp (type
, keep
, memory_required
, dont_promote
)
971 enum machine_mode mode
= TYPE_MODE (type
);
972 int unsignedp
= TREE_UNSIGNED (type
);
974 if (mode
== BLKmode
|| memory_required
)
976 HOST_WIDE_INT size
= int_size_in_bytes (type
);
979 /* Unfortunately, we don't yet know how to allocate variable-sized
980 temporaries. However, sometimes we have a fixed upper limit on
981 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
982 instead. This is the case for Chill variable-sized strings. */
983 if (size
== -1 && TREE_CODE (type
) == ARRAY_TYPE
984 && TYPE_ARRAY_MAX_SIZE (type
) != NULL_TREE
985 && TREE_CODE (TYPE_ARRAY_MAX_SIZE (type
)) == INTEGER_CST
)
986 size
= TREE_INT_CST_LOW (TYPE_ARRAY_MAX_SIZE (type
));
988 tmp
= assign_stack_temp (mode
, size
, keep
);
989 MEM_IN_STRUCT_P (tmp
) = AGGREGATE_TYPE_P (type
);
993 #ifndef PROMOTE_FOR_CALL_ONLY
995 mode
= promote_mode (type
, mode
, &unsignedp
, 0);
998 return gen_reg_rtx (mode
);
1001 /* Combine temporary stack slots which are adjacent on the stack.
1003 This allows for better use of already allocated stack space. This is only
1004 done for BLKmode slots because we can be sure that we won't have alignment
1005 problems in this case. */
1008 combine_temp_slots ()
1010 struct temp_slot
*p
, *q
;
1011 struct temp_slot
*prev_p
, *prev_q
;
1014 /* If there are a lot of temp slots, don't do anything unless
1015 high levels of optimizaton. */
1016 if (! flag_expensive_optimizations
)
1017 for (p
= temp_slots
, num_slots
= 0; p
; p
= p
->next
, num_slots
++)
1018 if (num_slots
> 100 || (num_slots
> 10 && optimize
== 0))
1021 for (p
= temp_slots
, prev_p
= 0; p
; p
= prev_p
? prev_p
->next
: temp_slots
)
1025 if (! p
->in_use
&& GET_MODE (p
->slot
) == BLKmode
)
1026 for (q
= p
->next
, prev_q
= p
; q
; q
= prev_q
->next
)
1029 if (! q
->in_use
&& GET_MODE (q
->slot
) == BLKmode
)
1031 if (p
->base_offset
+ p
->full_size
== q
->base_offset
)
1033 /* Q comes after P; combine Q into P. */
1035 p
->full_size
+= q
->full_size
;
1038 else if (q
->base_offset
+ q
->full_size
== p
->base_offset
)
1040 /* P comes after Q; combine P into Q. */
1042 q
->full_size
+= p
->full_size
;
1047 /* Either delete Q or advance past it. */
1049 prev_q
->next
= q
->next
;
1053 /* Either delete P or advance past it. */
1057 prev_p
->next
= p
->next
;
1059 temp_slots
= p
->next
;
1066 /* Find the temp slot corresponding to the object at address X. */
1068 static struct temp_slot
*
1069 find_temp_slot_from_address (x
)
1072 struct temp_slot
*p
;
1075 for (p
= temp_slots
; p
; p
= p
->next
)
1080 else if (XEXP (p
->slot
, 0) == x
1082 || (GET_CODE (x
) == PLUS
1083 && XEXP (x
, 0) == virtual_stack_vars_rtx
1084 && GET_CODE (XEXP (x
, 1)) == CONST_INT
1085 && INTVAL (XEXP (x
, 1)) >= p
->base_offset
1086 && INTVAL (XEXP (x
, 1)) < p
->base_offset
+ p
->full_size
))
1089 else if (p
->address
!= 0 && GET_CODE (p
->address
) == EXPR_LIST
)
1090 for (next
= p
->address
; next
; next
= XEXP (next
, 1))
1091 if (XEXP (next
, 0) == x
)
1098 /* Indicate that NEW is an alternate way of referring to the temp slot
1099 that previously was known by OLD. */
1102 update_temp_slot_address (old
, new)
1105 struct temp_slot
*p
= find_temp_slot_from_address (old
);
1107 /* If none, return. Else add NEW as an alias. */
1110 else if (p
->address
== 0)
1114 if (GET_CODE (p
->address
) != EXPR_LIST
)
1115 p
->address
= gen_rtx_EXPR_LIST (VOIDmode
, p
->address
, NULL_RTX
);
1117 p
->address
= gen_rtx_EXPR_LIST (VOIDmode
, new, p
->address
);
1121 /* If X could be a reference to a temporary slot, mark the fact that its
1122 address was taken. */
1125 mark_temp_addr_taken (x
)
1128 struct temp_slot
*p
;
1133 /* If X is not in memory or is at a constant address, it cannot be in
1134 a temporary slot. */
1135 if (GET_CODE (x
) != MEM
|| CONSTANT_P (XEXP (x
, 0)))
1138 p
= find_temp_slot_from_address (XEXP (x
, 0));
1143 /* If X could be a reference to a temporary slot, mark that slot as
1144 belonging to the to one level higher than the current level. If X
1145 matched one of our slots, just mark that one. Otherwise, we can't
1146 easily predict which it is, so upgrade all of them. Kept slots
1147 need not be touched.
1149 This is called when an ({...}) construct occurs and a statement
1150 returns a value in memory. */
1153 preserve_temp_slots (x
)
1156 struct temp_slot
*p
= 0;
1158 /* If there is no result, we still might have some objects whose address
1159 were taken, so we need to make sure they stay around. */
1162 for (p
= temp_slots
; p
; p
= p
->next
)
1163 if (p
->in_use
&& p
->level
== temp_slot_level
&& p
->addr_taken
)
1169 /* If X is a register that is being used as a pointer, see if we have
1170 a temporary slot we know it points to. To be consistent with
1171 the code below, we really should preserve all non-kept slots
1172 if we can't find a match, but that seems to be much too costly. */
1173 if (GET_CODE (x
) == REG
&& REGNO_POINTER_FLAG (REGNO (x
)))
1174 p
= find_temp_slot_from_address (x
);
1176 /* If X is not in memory or is at a constant address, it cannot be in
1177 a temporary slot, but it can contain something whose address was
1179 if (p
== 0 && (GET_CODE (x
) != MEM
|| CONSTANT_P (XEXP (x
, 0))))
1181 for (p
= temp_slots
; p
; p
= p
->next
)
1182 if (p
->in_use
&& p
->level
== temp_slot_level
&& p
->addr_taken
)
1188 /* First see if we can find a match. */
1190 p
= find_temp_slot_from_address (XEXP (x
, 0));
1194 /* Move everything at our level whose address was taken to our new
1195 level in case we used its address. */
1196 struct temp_slot
*q
;
1198 if (p
->level
== temp_slot_level
)
1200 for (q
= temp_slots
; q
; q
= q
->next
)
1201 if (q
!= p
&& q
->addr_taken
&& q
->level
== p
->level
)
1210 /* Otherwise, preserve all non-kept slots at this level. */
1211 for (p
= temp_slots
; p
; p
= p
->next
)
1212 if (p
->in_use
&& p
->level
== temp_slot_level
&& ! p
->keep
)
1216 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1217 with that RTL_EXPR, promote it into a temporary slot at the present
1218 level so it will not be freed when we free slots made in the
1222 preserve_rtl_expr_result (x
)
1225 struct temp_slot
*p
;
1227 /* If X is not in memory or is at a constant address, it cannot be in
1228 a temporary slot. */
1229 if (x
== 0 || GET_CODE (x
) != MEM
|| CONSTANT_P (XEXP (x
, 0)))
1232 /* If we can find a match, move it to our level unless it is already at
1234 p
= find_temp_slot_from_address (XEXP (x
, 0));
1237 p
->level
= MIN (p
->level
, temp_slot_level
);
1244 /* Free all temporaries used so far. This is normally called at the end
1245 of generating code for a statement. Don't free any temporaries
1246 currently in use for an RTL_EXPR that hasn't yet been emitted.
1247 We could eventually do better than this since it can be reused while
1248 generating the same RTL_EXPR, but this is complex and probably not
1254 struct temp_slot
*p
;
1256 for (p
= temp_slots
; p
; p
= p
->next
)
1257 if (p
->in_use
&& p
->level
== temp_slot_level
&& ! p
->keep
1258 && p
->rtl_expr
== 0)
1261 combine_temp_slots ();
1264 /* Free all temporary slots used in T, an RTL_EXPR node. */
1267 free_temps_for_rtl_expr (t
)
1270 struct temp_slot
*p
;
1272 for (p
= temp_slots
; p
; p
= p
->next
)
1273 if (p
->rtl_expr
== t
)
1276 combine_temp_slots ();
1279 /* Mark all temporaries ever allocated in this function as not suitable
1280 for reuse until the current level is exited. */
1283 mark_all_temps_used ()
1285 struct temp_slot
*p
;
1287 for (p
= temp_slots
; p
; p
= p
->next
)
1289 p
->in_use
= p
->keep
= 1;
1290 p
->level
= MIN (p
->level
, temp_slot_level
);
1294 /* Push deeper into the nesting level for stack temporaries. */
1302 /* Likewise, but save the new level as the place to allocate variables
1306 push_temp_slots_for_block ()
1310 var_temp_slot_level
= temp_slot_level
;
1313 /* Likewise, but save the new level as the place to allocate temporaries
1314 for TARGET_EXPRs. */
1317 push_temp_slots_for_target ()
1321 target_temp_slot_level
= temp_slot_level
;
1324 /* Set and get the value of target_temp_slot_level. The only
1325 permitted use of these functions is to save and restore this value. */
1328 get_target_temp_slot_level ()
1330 return target_temp_slot_level
;
1334 set_target_temp_slot_level (level
)
1337 target_temp_slot_level
= level
;
1340 /* Pop a temporary nesting level. All slots in use in the current level
1346 struct temp_slot
*p
;
1348 for (p
= temp_slots
; p
; p
= p
->next
)
1349 if (p
->in_use
&& p
->level
== temp_slot_level
&& p
->rtl_expr
== 0)
1352 combine_temp_slots ();
1357 /* Initialize temporary slots. */
1362 /* We have not allocated any temporaries yet. */
1364 temp_slot_level
= 0;
1365 var_temp_slot_level
= 0;
1366 target_temp_slot_level
= 0;
1369 /* Retroactively move an auto variable from a register to a stack slot.
1370 This is done when an address-reference to the variable is seen. */
1373 put_var_into_stack (decl
)
1377 enum machine_mode promoted_mode
, decl_mode
;
1378 struct function
*function
= 0;
1380 int can_use_addressof
;
1382 context
= decl_function_context (decl
);
1384 /* Get the current rtl used for this object and its original mode. */
1385 reg
= TREE_CODE (decl
) == SAVE_EXPR
? SAVE_EXPR_RTL (decl
) : DECL_RTL (decl
);
1387 /* No need to do anything if decl has no rtx yet
1388 since in that case caller is setting TREE_ADDRESSABLE
1389 and a stack slot will be assigned when the rtl is made. */
1393 /* Get the declared mode for this object. */
1394 decl_mode
= (TREE_CODE (decl
) == SAVE_EXPR
? TYPE_MODE (TREE_TYPE (decl
))
1395 : DECL_MODE (decl
));
1396 /* Get the mode it's actually stored in. */
1397 promoted_mode
= GET_MODE (reg
);
1399 /* If this variable comes from an outer function,
1400 find that function's saved context. */
1401 if (context
!= current_function_decl
&& context
!= inline_function_decl
)
1402 for (function
= outer_function_chain
; function
; function
= function
->next
)
1403 if (function
->decl
== context
)
1406 /* If this is a variable-size object with a pseudo to address it,
1407 put that pseudo into the stack, if the var is nonlocal. */
1408 if (DECL_NONLOCAL (decl
)
1409 && GET_CODE (reg
) == MEM
1410 && GET_CODE (XEXP (reg
, 0)) == REG
1411 && REGNO (XEXP (reg
, 0)) > LAST_VIRTUAL_REGISTER
)
1413 reg
= XEXP (reg
, 0);
1414 decl_mode
= promoted_mode
= GET_MODE (reg
);
1420 /* FIXME make it work for promoted modes too */
1421 && decl_mode
== promoted_mode
1422 #ifdef NON_SAVING_SETJMP
1423 && ! (NON_SAVING_SETJMP
&& current_function_calls_setjmp
)
1427 /* If we can't use ADDRESSOF, make sure we see through one we already
1429 if (! can_use_addressof
&& GET_CODE (reg
) == MEM
1430 && GET_CODE (XEXP (reg
, 0)) == ADDRESSOF
)
1431 reg
= XEXP (XEXP (reg
, 0), 0);
1433 /* Now we should have a value that resides in one or more pseudo regs. */
1435 if (GET_CODE (reg
) == REG
)
1437 /* If this variable lives in the current function and we don't need
1438 to put things in the stack for the sake of setjmp, try to keep it
1439 in a register until we know we actually need the address. */
1440 if (can_use_addressof
)
1441 gen_mem_addressof (reg
, decl
);
1443 put_reg_into_stack (function
, reg
, TREE_TYPE (decl
),
1444 promoted_mode
, decl_mode
,
1445 TREE_SIDE_EFFECTS (decl
), 0,
1447 || DECL_INITIAL (decl
) != 0);
1449 else if (GET_CODE (reg
) == CONCAT
)
1451 /* A CONCAT contains two pseudos; put them both in the stack.
1452 We do it so they end up consecutive. */
1453 enum machine_mode part_mode
= GET_MODE (XEXP (reg
, 0));
1454 tree part_type
= TREE_TYPE (TREE_TYPE (decl
));
1455 #ifdef FRAME_GROWS_DOWNWARD
1456 /* Since part 0 should have a lower address, do it second. */
1457 put_reg_into_stack (function
, XEXP (reg
, 1), part_type
, part_mode
,
1458 part_mode
, TREE_SIDE_EFFECTS (decl
), 0,
1459 TREE_USED (decl
) || DECL_INITIAL (decl
) != 0);
1460 put_reg_into_stack (function
, XEXP (reg
, 0), part_type
, part_mode
,
1461 part_mode
, TREE_SIDE_EFFECTS (decl
), 0,
1462 TREE_USED (decl
) || DECL_INITIAL (decl
) != 0);
1464 put_reg_into_stack (function
, XEXP (reg
, 0), part_type
, part_mode
,
1465 part_mode
, TREE_SIDE_EFFECTS (decl
), 0,
1466 TREE_USED (decl
) || DECL_INITIAL (decl
) != 0);
1467 put_reg_into_stack (function
, XEXP (reg
, 1), part_type
, part_mode
,
1468 part_mode
, TREE_SIDE_EFFECTS (decl
), 0,
1469 TREE_USED (decl
) || DECL_INITIAL (decl
) != 0);
1472 /* Change the CONCAT into a combined MEM for both parts. */
1473 PUT_CODE (reg
, MEM
);
1474 MEM_VOLATILE_P (reg
) = MEM_VOLATILE_P (XEXP (reg
, 0));
1475 MEM_ALIAS_SET (reg
) = get_alias_set (decl
);
1477 /* The two parts are in memory order already.
1478 Use the lower parts address as ours. */
1479 XEXP (reg
, 0) = XEXP (XEXP (reg
, 0), 0);
1480 /* Prevent sharing of rtl that might lose. */
1481 if (GET_CODE (XEXP (reg
, 0)) == PLUS
)
1482 XEXP (reg
, 0) = copy_rtx (XEXP (reg
, 0));
1487 if (flag_check_memory_usage
)
1488 emit_library_call (chkr_set_right_libfunc
, 1, VOIDmode
, 3,
1489 XEXP (reg
, 0), ptr_mode
,
1490 GEN_INT (GET_MODE_SIZE (GET_MODE (reg
))),
1491 TYPE_MODE (sizetype
),
1492 GEN_INT (MEMORY_USE_RW
),
1493 TYPE_MODE (integer_type_node
));
1496 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1497 into the stack frame of FUNCTION (0 means the current function).
1498 DECL_MODE is the machine mode of the user-level data type.
1499 PROMOTED_MODE is the machine mode of the register.
1500 VOLATILE_P is nonzero if this is for a "volatile" decl.
1501 USED_P is nonzero if this reg might have already been used in an insn. */
1504 put_reg_into_stack (function
, reg
, type
, promoted_mode
, decl_mode
, volatile_p
,
1505 original_regno
, used_p
)
1506 struct function
*function
;
1509 enum machine_mode promoted_mode
, decl_mode
;
1515 int regno
= original_regno
;
1518 regno
= REGNO (reg
);
1522 if (regno
< function
->max_parm_reg
)
1523 new = function
->parm_reg_stack_loc
[regno
];
1525 new = assign_outer_stack_local (decl_mode
, GET_MODE_SIZE (decl_mode
),
1530 if (regno
< max_parm_reg
)
1531 new = parm_reg_stack_loc
[regno
];
1533 new = assign_stack_local (decl_mode
, GET_MODE_SIZE (decl_mode
), 0);
1536 PUT_MODE (reg
, decl_mode
);
1537 XEXP (reg
, 0) = XEXP (new, 0);
1538 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1539 MEM_VOLATILE_P (reg
) = volatile_p
;
1540 PUT_CODE (reg
, MEM
);
1542 /* If this is a memory ref that contains aggregate components,
1543 mark it as such for cse and loop optimize. If we are reusing a
1544 previously generated stack slot, then we need to copy the bit in
1545 case it was set for other reasons. For instance, it is set for
1546 __builtin_va_alist. */
1547 MEM_IN_STRUCT_P (reg
) = AGGREGATE_TYPE_P (type
) | MEM_IN_STRUCT_P (new);
1548 MEM_ALIAS_SET (reg
) = get_alias_set (type
);
1550 /* Now make sure that all refs to the variable, previously made
1551 when it was a register, are fixed up to be valid again. */
1553 if (used_p
&& function
!= 0)
1555 struct var_refs_queue
*temp
;
1557 /* Variable is inherited; fix it up when we get back to its function. */
1558 push_obstacks (function
->function_obstack
,
1559 function
->function_maybepermanent_obstack
);
1561 /* See comment in restore_tree_status in tree.c for why this needs to be
1562 on saveable obstack. */
1564 = (struct var_refs_queue
*) savealloc (sizeof (struct var_refs_queue
));
1565 temp
->modified
= reg
;
1566 temp
->promoted_mode
= promoted_mode
;
1567 temp
->unsignedp
= TREE_UNSIGNED (type
);
1568 temp
->next
= function
->fixup_var_refs_queue
;
1569 function
->fixup_var_refs_queue
= temp
;
1573 /* Variable is local; fix it up now. */
1574 fixup_var_refs (reg
, promoted_mode
, TREE_UNSIGNED (type
));
1578 fixup_var_refs (var
, promoted_mode
, unsignedp
)
1580 enum machine_mode promoted_mode
;
1584 rtx first_insn
= get_insns ();
1585 struct sequence_stack
*stack
= sequence_stack
;
1586 tree rtl_exps
= rtl_expr_chain
;
1588 /* Must scan all insns for stack-refs that exceed the limit. */
1589 fixup_var_refs_insns (var
, promoted_mode
, unsignedp
, first_insn
, stack
== 0);
1591 /* Scan all pending sequences too. */
1592 for (; stack
; stack
= stack
->next
)
1594 push_to_sequence (stack
->first
);
1595 fixup_var_refs_insns (var
, promoted_mode
, unsignedp
,
1596 stack
->first
, stack
->next
!= 0);
1597 /* Update remembered end of sequence
1598 in case we added an insn at the end. */
1599 stack
->last
= get_last_insn ();
1603 /* Scan all waiting RTL_EXPRs too. */
1604 for (pending
= rtl_exps
; pending
; pending
= TREE_CHAIN (pending
))
1606 rtx seq
= RTL_EXPR_SEQUENCE (TREE_VALUE (pending
));
1607 if (seq
!= const0_rtx
&& seq
!= 0)
1609 push_to_sequence (seq
);
1610 fixup_var_refs_insns (var
, promoted_mode
, unsignedp
, seq
, 0);
1616 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1617 some part of an insn. Return a struct fixup_replacement whose OLD
1618 value is equal to X. Allocate a new structure if no such entry exists. */
1620 static struct fixup_replacement
*
1621 find_fixup_replacement (replacements
, x
)
1622 struct fixup_replacement
**replacements
;
1625 struct fixup_replacement
*p
;
1627 /* See if we have already replaced this. */
1628 for (p
= *replacements
; p
&& p
->old
!= x
; p
= p
->next
)
1633 p
= (struct fixup_replacement
*) oballoc (sizeof (struct fixup_replacement
));
1636 p
->next
= *replacements
;
1643 /* Scan the insn-chain starting with INSN for refs to VAR
1644 and fix them up. TOPLEVEL is nonzero if this chain is the
1645 main chain of insns for the current function. */
1648 fixup_var_refs_insns (var
, promoted_mode
, unsignedp
, insn
, toplevel
)
1650 enum machine_mode promoted_mode
;
1659 rtx next
= NEXT_INSN (insn
);
1660 rtx set
, prev
, prev_set
;
1663 if (GET_RTX_CLASS (GET_CODE (insn
)) == 'i')
1665 /* If this is a CLOBBER of VAR, delete it.
1667 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1668 and REG_RETVAL notes too. */
1669 if (GET_CODE (PATTERN (insn
)) == CLOBBER
1670 && (XEXP (PATTERN (insn
), 0) == var
1671 || (GET_CODE (XEXP (PATTERN (insn
), 0)) == CONCAT
1672 && (XEXP (XEXP (PATTERN (insn
), 0), 0) == var
1673 || XEXP (XEXP (PATTERN (insn
), 0), 1) == var
))))
1675 if ((note
= find_reg_note (insn
, REG_LIBCALL
, NULL_RTX
)) != 0)
1676 /* The REG_LIBCALL note will go away since we are going to
1677 turn INSN into a NOTE, so just delete the
1678 corresponding REG_RETVAL note. */
1679 remove_note (XEXP (note
, 0),
1680 find_reg_note (XEXP (note
, 0), REG_RETVAL
,
1683 /* In unoptimized compilation, we shouldn't call delete_insn
1684 except in jump.c doing warnings. */
1685 PUT_CODE (insn
, NOTE
);
1686 NOTE_LINE_NUMBER (insn
) = NOTE_INSN_DELETED
;
1687 NOTE_SOURCE_FILE (insn
) = 0;
1690 /* The insn to load VAR from a home in the arglist
1691 is now a no-op. When we see it, just delete it.
1692 Similarly if this is storing VAR from a register from which
1693 it was loaded in the previous insn. This will occur
1694 when an ADDRESSOF was made for an arglist slot. */
1696 && (set
= single_set (insn
)) != 0
1697 && SET_DEST (set
) == var
1698 /* If this represents the result of an insn group,
1699 don't delete the insn. */
1700 && find_reg_note (insn
, REG_RETVAL
, NULL_RTX
) == 0
1701 && (rtx_equal_p (SET_SRC (set
), var
)
1702 || (GET_CODE (SET_SRC (set
)) == REG
1703 && (prev
= prev_nonnote_insn (insn
)) != 0
1704 && (prev_set
= single_set (prev
)) != 0
1705 && SET_DEST (prev_set
) == SET_SRC (set
)
1706 && rtx_equal_p (SET_SRC (prev_set
), var
))))
1708 /* In unoptimized compilation, we shouldn't call delete_insn
1709 except in jump.c doing warnings. */
1710 PUT_CODE (insn
, NOTE
);
1711 NOTE_LINE_NUMBER (insn
) = NOTE_INSN_DELETED
;
1712 NOTE_SOURCE_FILE (insn
) = 0;
1713 if (insn
== last_parm_insn
)
1714 last_parm_insn
= PREV_INSN (next
);
1718 struct fixup_replacement
*replacements
= 0;
1719 rtx next_insn
= NEXT_INSN (insn
);
1721 if (SMALL_REGISTER_CLASSES
)
1723 /* If the insn that copies the results of a CALL_INSN
1724 into a pseudo now references VAR, we have to use an
1725 intermediate pseudo since we want the life of the
1726 return value register to be only a single insn.
1728 If we don't use an intermediate pseudo, such things as
1729 address computations to make the address of VAR valid
1730 if it is not can be placed between the CALL_INSN and INSN.
1732 To make sure this doesn't happen, we record the destination
1733 of the CALL_INSN and see if the next insn uses both that
1736 if (call_dest
!= 0 && GET_CODE (insn
) == INSN
1737 && reg_mentioned_p (var
, PATTERN (insn
))
1738 && reg_mentioned_p (call_dest
, PATTERN (insn
)))
1740 rtx temp
= gen_reg_rtx (GET_MODE (call_dest
));
1742 emit_insn_before (gen_move_insn (temp
, call_dest
), insn
);
1744 PATTERN (insn
) = replace_rtx (PATTERN (insn
),
1748 if (GET_CODE (insn
) == CALL_INSN
1749 && GET_CODE (PATTERN (insn
)) == SET
)
1750 call_dest
= SET_DEST (PATTERN (insn
));
1751 else if (GET_CODE (insn
) == CALL_INSN
1752 && GET_CODE (PATTERN (insn
)) == PARALLEL
1753 && GET_CODE (XVECEXP (PATTERN (insn
), 0, 0)) == SET
)
1754 call_dest
= SET_DEST (XVECEXP (PATTERN (insn
), 0, 0));
1759 /* See if we have to do anything to INSN now that VAR is in
1760 memory. If it needs to be loaded into a pseudo, use a single
1761 pseudo for the entire insn in case there is a MATCH_DUP
1762 between two operands. We pass a pointer to the head of
1763 a list of struct fixup_replacements. If fixup_var_refs_1
1764 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1765 it will record them in this list.
1767 If it allocated a pseudo for any replacement, we copy into
1770 fixup_var_refs_1 (var
, promoted_mode
, &PATTERN (insn
), insn
,
1773 /* If this is last_parm_insn, and any instructions were output
1774 after it to fix it up, then we must set last_parm_insn to
1775 the last such instruction emitted. */
1776 if (insn
== last_parm_insn
)
1777 last_parm_insn
= PREV_INSN (next_insn
);
1779 while (replacements
)
1781 if (GET_CODE (replacements
->new) == REG
)
1786 /* OLD might be a (subreg (mem)). */
1787 if (GET_CODE (replacements
->old
) == SUBREG
)
1789 = fixup_memory_subreg (replacements
->old
, insn
, 0);
1792 = fixup_stack_1 (replacements
->old
, insn
);
1794 insert_before
= insn
;
1796 /* If we are changing the mode, do a conversion.
1797 This might be wasteful, but combine.c will
1798 eliminate much of the waste. */
1800 if (GET_MODE (replacements
->new)
1801 != GET_MODE (replacements
->old
))
1804 convert_move (replacements
->new,
1805 replacements
->old
, unsignedp
);
1806 seq
= gen_sequence ();
1810 seq
= gen_move_insn (replacements
->new,
1813 emit_insn_before (seq
, insert_before
);
1816 replacements
= replacements
->next
;
1820 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1821 But don't touch other insns referred to by reg-notes;
1822 we will get them elsewhere. */
1823 for (note
= REG_NOTES (insn
); note
; note
= XEXP (note
, 1))
1824 if (GET_CODE (note
) != INSN_LIST
)
1826 = walk_fixup_memory_subreg (XEXP (note
, 0), insn
, 1);
1832 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1833 See if the rtx expression at *LOC in INSN needs to be changed.
1835 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1836 contain a list of original rtx's and replacements. If we find that we need
1837 to modify this insn by replacing a memory reference with a pseudo or by
1838 making a new MEM to implement a SUBREG, we consult that list to see if
1839 we have already chosen a replacement. If none has already been allocated,
1840 we allocate it and update the list. fixup_var_refs_insns will copy VAR
1841 or the SUBREG, as appropriate, to the pseudo. */
1844 fixup_var_refs_1 (var
, promoted_mode
, loc
, insn
, replacements
)
1846 enum machine_mode promoted_mode
;
1849 struct fixup_replacement
**replacements
;
1852 register rtx x
= *loc
;
1853 RTX_CODE code
= GET_CODE (x
);
1855 register rtx tem
, tem1
;
1856 struct fixup_replacement
*replacement
;
1861 if (XEXP (x
, 0) == var
)
1863 /* Prevent sharing of rtl that might lose. */
1864 rtx sub
= copy_rtx (XEXP (var
, 0));
1868 if (! validate_change (insn
, loc
, sub
, 0))
1870 rtx y
= force_operand (sub
, NULL_RTX
);
1872 if (! validate_change (insn
, loc
, y
, 0))
1873 *loc
= copy_to_reg (y
);
1876 emit_insn_before (gen_sequence (), insn
);
1884 /* If we already have a replacement, use it. Otherwise,
1885 try to fix up this address in case it is invalid. */
1887 replacement
= find_fixup_replacement (replacements
, var
);
1888 if (replacement
->new)
1890 *loc
= replacement
->new;
1894 *loc
= replacement
->new = x
= fixup_stack_1 (x
, insn
);
1896 /* Unless we are forcing memory to register or we changed the mode,
1897 we can leave things the way they are if the insn is valid. */
1899 INSN_CODE (insn
) = -1;
1900 if (! flag_force_mem
&& GET_MODE (x
) == promoted_mode
1901 && recog_memoized (insn
) >= 0)
1904 *loc
= replacement
->new = gen_reg_rtx (promoted_mode
);
1908 /* If X contains VAR, we need to unshare it here so that we update
1909 each occurrence separately. But all identical MEMs in one insn
1910 must be replaced with the same rtx because of the possibility of
1913 if (reg_mentioned_p (var
, x
))
1915 replacement
= find_fixup_replacement (replacements
, x
);
1916 if (replacement
->new == 0)
1917 replacement
->new = copy_most_rtx (x
, var
);
1919 *loc
= x
= replacement
->new;
1935 /* Note that in some cases those types of expressions are altered
1936 by optimize_bit_field, and do not survive to get here. */
1937 if (XEXP (x
, 0) == var
1938 || (GET_CODE (XEXP (x
, 0)) == SUBREG
1939 && SUBREG_REG (XEXP (x
, 0)) == var
))
1941 /* Get TEM as a valid MEM in the mode presently in the insn.
1943 We don't worry about the possibility of MATCH_DUP here; it
1944 is highly unlikely and would be tricky to handle. */
1947 if (GET_CODE (tem
) == SUBREG
)
1949 if (GET_MODE_BITSIZE (GET_MODE (tem
))
1950 > GET_MODE_BITSIZE (GET_MODE (var
)))
1952 replacement
= find_fixup_replacement (replacements
, var
);
1953 if (replacement
->new == 0)
1954 replacement
->new = gen_reg_rtx (GET_MODE (var
));
1955 SUBREG_REG (tem
) = replacement
->new;
1958 tem
= fixup_memory_subreg (tem
, insn
, 0);
1961 tem
= fixup_stack_1 (tem
, insn
);
1963 /* Unless we want to load from memory, get TEM into the proper mode
1964 for an extract from memory. This can only be done if the
1965 extract is at a constant position and length. */
1967 if (! flag_force_mem
&& GET_CODE (XEXP (x
, 1)) == CONST_INT
1968 && GET_CODE (XEXP (x
, 2)) == CONST_INT
1969 && ! mode_dependent_address_p (XEXP (tem
, 0))
1970 && ! MEM_VOLATILE_P (tem
))
1972 enum machine_mode wanted_mode
= VOIDmode
;
1973 enum machine_mode is_mode
= GET_MODE (tem
);
1974 HOST_WIDE_INT pos
= INTVAL (XEXP (x
, 2));
1977 if (GET_CODE (x
) == ZERO_EXTRACT
)
1979 wanted_mode
= insn_operand_mode
[(int) CODE_FOR_extzv
][1];
1980 if (wanted_mode
== VOIDmode
)
1981 wanted_mode
= word_mode
;
1985 if (GET_CODE (x
) == SIGN_EXTRACT
)
1987 wanted_mode
= insn_operand_mode
[(int) CODE_FOR_extv
][1];
1988 if (wanted_mode
== VOIDmode
)
1989 wanted_mode
= word_mode
;
1992 /* If we have a narrower mode, we can do something. */
1993 if (wanted_mode
!= VOIDmode
1994 && GET_MODE_SIZE (wanted_mode
) < GET_MODE_SIZE (is_mode
))
1996 HOST_WIDE_INT offset
= pos
/ BITS_PER_UNIT
;
1997 rtx old_pos
= XEXP (x
, 2);
2000 /* If the bytes and bits are counted differently, we
2001 must adjust the offset. */
2002 if (BYTES_BIG_ENDIAN
!= BITS_BIG_ENDIAN
)
2003 offset
= (GET_MODE_SIZE (is_mode
)
2004 - GET_MODE_SIZE (wanted_mode
) - offset
);
2006 pos
%= GET_MODE_BITSIZE (wanted_mode
);
2008 newmem
= gen_rtx_MEM (wanted_mode
,
2009 plus_constant (XEXP (tem
, 0), offset
));
2010 RTX_UNCHANGING_P (newmem
) = RTX_UNCHANGING_P (tem
);
2011 MEM_VOLATILE_P (newmem
) = MEM_VOLATILE_P (tem
);
2012 MEM_IN_STRUCT_P (newmem
) = MEM_IN_STRUCT_P (tem
);
2014 /* Make the change and see if the insn remains valid. */
2015 INSN_CODE (insn
) = -1;
2016 XEXP (x
, 0) = newmem
;
2017 XEXP (x
, 2) = GEN_INT (pos
);
2019 if (recog_memoized (insn
) >= 0)
2022 /* Otherwise, restore old position. XEXP (x, 0) will be
2024 XEXP (x
, 2) = old_pos
;
2028 /* If we get here, the bitfield extract insn can't accept a memory
2029 reference. Copy the input into a register. */
2031 tem1
= gen_reg_rtx (GET_MODE (tem
));
2032 emit_insn_before (gen_move_insn (tem1
, tem
), insn
);
2039 if (SUBREG_REG (x
) == var
)
2041 /* If this is a special SUBREG made because VAR was promoted
2042 from a wider mode, replace it with VAR and call ourself
2043 recursively, this time saying that the object previously
2044 had its current mode (by virtue of the SUBREG). */
2046 if (SUBREG_PROMOTED_VAR_P (x
))
2049 fixup_var_refs_1 (var
, GET_MODE (var
), loc
, insn
, replacements
);
2053 /* If this SUBREG makes VAR wider, it has become a paradoxical
2054 SUBREG with VAR in memory, but these aren't allowed at this
2055 stage of the compilation. So load VAR into a pseudo and take
2056 a SUBREG of that pseudo. */
2057 if (GET_MODE_SIZE (GET_MODE (x
)) > GET_MODE_SIZE (GET_MODE (var
)))
2059 replacement
= find_fixup_replacement (replacements
, var
);
2060 if (replacement
->new == 0)
2061 replacement
->new = gen_reg_rtx (GET_MODE (var
));
2062 SUBREG_REG (x
) = replacement
->new;
2066 /* See if we have already found a replacement for this SUBREG.
2067 If so, use it. Otherwise, make a MEM and see if the insn
2068 is recognized. If not, or if we should force MEM into a register,
2069 make a pseudo for this SUBREG. */
2070 replacement
= find_fixup_replacement (replacements
, x
);
2071 if (replacement
->new)
2073 *loc
= replacement
->new;
2077 replacement
->new = *loc
= fixup_memory_subreg (x
, insn
, 0);
2079 INSN_CODE (insn
) = -1;
2080 if (! flag_force_mem
&& recog_memoized (insn
) >= 0)
2083 *loc
= replacement
->new = gen_reg_rtx (GET_MODE (x
));
2089 /* First do special simplification of bit-field references. */
2090 if (GET_CODE (SET_DEST (x
)) == SIGN_EXTRACT
2091 || GET_CODE (SET_DEST (x
)) == ZERO_EXTRACT
)
2092 optimize_bit_field (x
, insn
, 0);
2093 if (GET_CODE (SET_SRC (x
)) == SIGN_EXTRACT
2094 || GET_CODE (SET_SRC (x
)) == ZERO_EXTRACT
)
2095 optimize_bit_field (x
, insn
, NULL_PTR
);
2097 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2098 into a register and then store it back out. */
2099 if (GET_CODE (SET_DEST (x
)) == ZERO_EXTRACT
2100 && GET_CODE (XEXP (SET_DEST (x
), 0)) == SUBREG
2101 && SUBREG_REG (XEXP (SET_DEST (x
), 0)) == var
2102 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x
), 0)))
2103 > GET_MODE_SIZE (GET_MODE (var
))))
2105 replacement
= find_fixup_replacement (replacements
, var
);
2106 if (replacement
->new == 0)
2107 replacement
->new = gen_reg_rtx (GET_MODE (var
));
2109 SUBREG_REG (XEXP (SET_DEST (x
), 0)) = replacement
->new;
2110 emit_insn_after (gen_move_insn (var
, replacement
->new), insn
);
2113 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2114 insn into a pseudo and store the low part of the pseudo into VAR. */
2115 if (GET_CODE (SET_DEST (x
)) == SUBREG
2116 && SUBREG_REG (SET_DEST (x
)) == var
2117 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x
)))
2118 > GET_MODE_SIZE (GET_MODE (var
))))
2120 SET_DEST (x
) = tem
= gen_reg_rtx (GET_MODE (SET_DEST (x
)));
2121 emit_insn_after (gen_move_insn (var
, gen_lowpart (GET_MODE (var
),
2128 rtx dest
= SET_DEST (x
);
2129 rtx src
= SET_SRC (x
);
2131 rtx outerdest
= dest
;
2134 while (GET_CODE (dest
) == SUBREG
|| GET_CODE (dest
) == STRICT_LOW_PART
2135 || GET_CODE (dest
) == SIGN_EXTRACT
2136 || GET_CODE (dest
) == ZERO_EXTRACT
)
2137 dest
= XEXP (dest
, 0);
2139 if (GET_CODE (src
) == SUBREG
)
2140 src
= XEXP (src
, 0);
2142 /* If VAR does not appear at the top level of the SET
2143 just scan the lower levels of the tree. */
2145 if (src
!= var
&& dest
!= var
)
2148 /* We will need to rerecognize this insn. */
2149 INSN_CODE (insn
) = -1;
2152 if (GET_CODE (outerdest
) == ZERO_EXTRACT
&& dest
== var
)
2154 /* Since this case will return, ensure we fixup all the
2156 fixup_var_refs_1 (var
, promoted_mode
, &XEXP (outerdest
, 1),
2157 insn
, replacements
);
2158 fixup_var_refs_1 (var
, promoted_mode
, &XEXP (outerdest
, 2),
2159 insn
, replacements
);
2160 fixup_var_refs_1 (var
, promoted_mode
, &SET_SRC (x
),
2161 insn
, replacements
);
2163 tem
= XEXP (outerdest
, 0);
2165 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2166 that may appear inside a ZERO_EXTRACT.
2167 This was legitimate when the MEM was a REG. */
2168 if (GET_CODE (tem
) == SUBREG
2169 && SUBREG_REG (tem
) == var
)
2170 tem
= fixup_memory_subreg (tem
, insn
, 0);
2172 tem
= fixup_stack_1 (tem
, insn
);
2174 if (GET_CODE (XEXP (outerdest
, 1)) == CONST_INT
2175 && GET_CODE (XEXP (outerdest
, 2)) == CONST_INT
2176 && ! mode_dependent_address_p (XEXP (tem
, 0))
2177 && ! MEM_VOLATILE_P (tem
))
2179 enum machine_mode wanted_mode
;
2180 enum machine_mode is_mode
= GET_MODE (tem
);
2181 HOST_WIDE_INT pos
= INTVAL (XEXP (outerdest
, 2));
2183 wanted_mode
= insn_operand_mode
[(int) CODE_FOR_insv
][0];
2184 if (wanted_mode
== VOIDmode
)
2185 wanted_mode
= word_mode
;
2187 /* If we have a narrower mode, we can do something. */
2188 if (GET_MODE_SIZE (wanted_mode
) < GET_MODE_SIZE (is_mode
))
2190 HOST_WIDE_INT offset
= pos
/ BITS_PER_UNIT
;
2191 rtx old_pos
= XEXP (outerdest
, 2);
2194 if (BYTES_BIG_ENDIAN
!= BITS_BIG_ENDIAN
)
2195 offset
= (GET_MODE_SIZE (is_mode
)
2196 - GET_MODE_SIZE (wanted_mode
) - offset
);
2198 pos
%= GET_MODE_BITSIZE (wanted_mode
);
2200 newmem
= gen_rtx_MEM (wanted_mode
,
2201 plus_constant (XEXP (tem
, 0), offset
));
2202 RTX_UNCHANGING_P (newmem
) = RTX_UNCHANGING_P (tem
);
2203 MEM_VOLATILE_P (newmem
) = MEM_VOLATILE_P (tem
);
2204 MEM_IN_STRUCT_P (newmem
) = MEM_IN_STRUCT_P (tem
);
2206 /* Make the change and see if the insn remains valid. */
2207 INSN_CODE (insn
) = -1;
2208 XEXP (outerdest
, 0) = newmem
;
2209 XEXP (outerdest
, 2) = GEN_INT (pos
);
2211 if (recog_memoized (insn
) >= 0)
2214 /* Otherwise, restore old position. XEXP (x, 0) will be
2216 XEXP (outerdest
, 2) = old_pos
;
2220 /* If we get here, the bit-field store doesn't allow memory
2221 or isn't located at a constant position. Load the value into
2222 a register, do the store, and put it back into memory. */
2224 tem1
= gen_reg_rtx (GET_MODE (tem
));
2225 emit_insn_before (gen_move_insn (tem1
, tem
), insn
);
2226 emit_insn_after (gen_move_insn (tem
, tem1
), insn
);
2227 XEXP (outerdest
, 0) = tem1
;
2232 /* STRICT_LOW_PART is a no-op on memory references
2233 and it can cause combinations to be unrecognizable,
2236 if (dest
== var
&& GET_CODE (SET_DEST (x
)) == STRICT_LOW_PART
)
2237 SET_DEST (x
) = XEXP (SET_DEST (x
), 0);
2239 /* A valid insn to copy VAR into or out of a register
2240 must be left alone, to avoid an infinite loop here.
2241 If the reference to VAR is by a subreg, fix that up,
2242 since SUBREG is not valid for a memref.
2243 Also fix up the address of the stack slot.
2245 Note that we must not try to recognize the insn until
2246 after we know that we have valid addresses and no
2247 (subreg (mem ...) ...) constructs, since these interfere
2248 with determining the validity of the insn. */
2250 if ((SET_SRC (x
) == var
2251 || (GET_CODE (SET_SRC (x
)) == SUBREG
2252 && SUBREG_REG (SET_SRC (x
)) == var
))
2253 && (GET_CODE (SET_DEST (x
)) == REG
2254 || (GET_CODE (SET_DEST (x
)) == SUBREG
2255 && GET_CODE (SUBREG_REG (SET_DEST (x
))) == REG
))
2256 && GET_MODE (var
) == promoted_mode
2257 && x
== single_set (insn
))
2261 replacement
= find_fixup_replacement (replacements
, SET_SRC (x
));
2262 if (replacement
->new)
2263 SET_SRC (x
) = replacement
->new;
2264 else if (GET_CODE (SET_SRC (x
)) == SUBREG
)
2265 SET_SRC (x
) = replacement
->new
2266 = fixup_memory_subreg (SET_SRC (x
), insn
, 0);
2268 SET_SRC (x
) = replacement
->new
2269 = fixup_stack_1 (SET_SRC (x
), insn
);
2271 if (recog_memoized (insn
) >= 0)
2274 /* INSN is not valid, but we know that we want to
2275 copy SET_SRC (x) to SET_DEST (x) in some way. So
2276 we generate the move and see whether it requires more
2277 than one insn. If it does, we emit those insns and
2278 delete INSN. Otherwise, we an just replace the pattern
2279 of INSN; we have already verified above that INSN has
2280 no other function that to do X. */
2282 pat
= gen_move_insn (SET_DEST (x
), SET_SRC (x
));
2283 if (GET_CODE (pat
) == SEQUENCE
)
2285 emit_insn_after (pat
, insn
);
2286 PUT_CODE (insn
, NOTE
);
2287 NOTE_LINE_NUMBER (insn
) = NOTE_INSN_DELETED
;
2288 NOTE_SOURCE_FILE (insn
) = 0;
2291 PATTERN (insn
) = pat
;
2296 if ((SET_DEST (x
) == var
2297 || (GET_CODE (SET_DEST (x
)) == SUBREG
2298 && SUBREG_REG (SET_DEST (x
)) == var
))
2299 && (GET_CODE (SET_SRC (x
)) == REG
2300 || (GET_CODE (SET_SRC (x
)) == SUBREG
2301 && GET_CODE (SUBREG_REG (SET_SRC (x
))) == REG
))
2302 && GET_MODE (var
) == promoted_mode
2303 && x
== single_set (insn
))
2307 if (GET_CODE (SET_DEST (x
)) == SUBREG
)
2308 SET_DEST (x
) = fixup_memory_subreg (SET_DEST (x
), insn
, 0);
2310 SET_DEST (x
) = fixup_stack_1 (SET_DEST (x
), insn
);
2312 if (recog_memoized (insn
) >= 0)
2315 pat
= gen_move_insn (SET_DEST (x
), SET_SRC (x
));
2316 if (GET_CODE (pat
) == SEQUENCE
)
2318 emit_insn_after (pat
, insn
);
2319 PUT_CODE (insn
, NOTE
);
2320 NOTE_LINE_NUMBER (insn
) = NOTE_INSN_DELETED
;
2321 NOTE_SOURCE_FILE (insn
) = 0;
2324 PATTERN (insn
) = pat
;
2329 /* Otherwise, storing into VAR must be handled specially
2330 by storing into a temporary and copying that into VAR
2331 with a new insn after this one. Note that this case
2332 will be used when storing into a promoted scalar since
2333 the insn will now have different modes on the input
2334 and output and hence will be invalid (except for the case
2335 of setting it to a constant, which does not need any
2336 change if it is valid). We generate extra code in that case,
2337 but combine.c will eliminate it. */
2342 rtx fixeddest
= SET_DEST (x
);
2344 /* STRICT_LOW_PART can be discarded, around a MEM. */
2345 if (GET_CODE (fixeddest
) == STRICT_LOW_PART
)
2346 fixeddest
= XEXP (fixeddest
, 0);
2347 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2348 if (GET_CODE (fixeddest
) == SUBREG
)
2350 fixeddest
= fixup_memory_subreg (fixeddest
, insn
, 0);
2351 promoted_mode
= GET_MODE (fixeddest
);
2354 fixeddest
= fixup_stack_1 (fixeddest
, insn
);
2356 temp
= gen_reg_rtx (promoted_mode
);
2358 emit_insn_after (gen_move_insn (fixeddest
,
2359 gen_lowpart (GET_MODE (fixeddest
),
2363 SET_DEST (x
) = temp
;
2371 /* Nothing special about this RTX; fix its operands. */
2373 fmt
= GET_RTX_FORMAT (code
);
2374 for (i
= GET_RTX_LENGTH (code
) - 1; i
>= 0; i
--)
2377 fixup_var_refs_1 (var
, promoted_mode
, &XEXP (x
, i
), insn
, replacements
);
2381 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
2382 fixup_var_refs_1 (var
, promoted_mode
, &XVECEXP (x
, i
, j
),
2383 insn
, replacements
);
2388 /* Given X, an rtx of the form (SUBREG:m1 (MEM:m2 addr)),
2389 return an rtx (MEM:m1 newaddr) which is equivalent.
2390 If any insns must be emitted to compute NEWADDR, put them before INSN.
2392 UNCRITICAL nonzero means accept paradoxical subregs.
2393 This is used for subregs found inside REG_NOTES. */
2396 fixup_memory_subreg (x
, insn
, uncritical
)
2401 int offset
= SUBREG_WORD (x
) * UNITS_PER_WORD
;
2402 rtx addr
= XEXP (SUBREG_REG (x
), 0);
2403 enum machine_mode mode
= GET_MODE (x
);
2406 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2407 if (GET_MODE_SIZE (mode
) > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x
)))
2411 if (BYTES_BIG_ENDIAN
)
2412 offset
+= (MIN (UNITS_PER_WORD
, GET_MODE_SIZE (GET_MODE (SUBREG_REG (x
))))
2413 - MIN (UNITS_PER_WORD
, GET_MODE_SIZE (mode
)));
2414 addr
= plus_constant (addr
, offset
);
2415 if (!flag_force_addr
&& memory_address_p (mode
, addr
))
2416 /* Shortcut if no insns need be emitted. */
2417 return change_address (SUBREG_REG (x
), mode
, addr
);
2419 result
= change_address (SUBREG_REG (x
), mode
, addr
);
2420 emit_insn_before (gen_sequence (), insn
);
2425 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2426 Replace subexpressions of X in place.
2427 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2428 Otherwise return X, with its contents possibly altered.
2430 If any insns must be emitted to compute NEWADDR, put them before INSN.
2432 UNCRITICAL is as in fixup_memory_subreg. */
2435 walk_fixup_memory_subreg (x
, insn
, uncritical
)
2440 register enum rtx_code code
;
2447 code
= GET_CODE (x
);
2449 if (code
== SUBREG
&& GET_CODE (SUBREG_REG (x
)) == MEM
)
2450 return fixup_memory_subreg (x
, insn
, uncritical
);
2452 /* Nothing special about this RTX; fix its operands. */
2454 fmt
= GET_RTX_FORMAT (code
);
2455 for (i
= GET_RTX_LENGTH (code
) - 1; i
>= 0; i
--)
2458 XEXP (x
, i
) = walk_fixup_memory_subreg (XEXP (x
, i
), insn
, uncritical
);
2462 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
2464 = walk_fixup_memory_subreg (XVECEXP (x
, i
, j
), insn
, uncritical
);
2470 /* For each memory ref within X, if it refers to a stack slot
2471 with an out of range displacement, put the address in a temp register
2472 (emitting new insns before INSN to load these registers)
2473 and alter the memory ref to use that register.
2474 Replace each such MEM rtx with a copy, to avoid clobberage. */
2477 fixup_stack_1 (x
, insn
)
2482 register RTX_CODE code
= GET_CODE (x
);
2487 register rtx ad
= XEXP (x
, 0);
2488 /* If we have address of a stack slot but it's not valid
2489 (displacement is too large), compute the sum in a register. */
2490 if (GET_CODE (ad
) == PLUS
2491 && GET_CODE (XEXP (ad
, 0)) == REG
2492 && ((REGNO (XEXP (ad
, 0)) >= FIRST_VIRTUAL_REGISTER
2493 && REGNO (XEXP (ad
, 0)) <= LAST_VIRTUAL_REGISTER
)
2494 || REGNO (XEXP (ad
, 0)) == FRAME_POINTER_REGNUM
2495 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2496 || REGNO (XEXP (ad
, 0)) == HARD_FRAME_POINTER_REGNUM
2498 || REGNO (XEXP (ad
, 0)) == STACK_POINTER_REGNUM
2499 || REGNO (XEXP (ad
, 0)) == ARG_POINTER_REGNUM
2500 || XEXP (ad
, 0) == current_function_internal_arg_pointer
)
2501 && GET_CODE (XEXP (ad
, 1)) == CONST_INT
)
2504 if (memory_address_p (GET_MODE (x
), ad
))
2508 temp
= copy_to_reg (ad
);
2509 seq
= gen_sequence ();
2511 emit_insn_before (seq
, insn
);
2512 return change_address (x
, VOIDmode
, temp
);
2517 fmt
= GET_RTX_FORMAT (code
);
2518 for (i
= GET_RTX_LENGTH (code
) - 1; i
>= 0; i
--)
2521 XEXP (x
, i
) = fixup_stack_1 (XEXP (x
, i
), insn
);
2525 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
2526 XVECEXP (x
, i
, j
) = fixup_stack_1 (XVECEXP (x
, i
, j
), insn
);
2532 /* Optimization: a bit-field instruction whose field
2533 happens to be a byte or halfword in memory
2534 can be changed to a move instruction.
2536 We call here when INSN is an insn to examine or store into a bit-field.
2537 BODY is the SET-rtx to be altered.
2539 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2540 (Currently this is called only from function.c, and EQUIV_MEM
2544 optimize_bit_field (body
, insn
, equiv_mem
)
2549 register rtx bitfield
;
2552 enum machine_mode mode
;
2554 if (GET_CODE (SET_DEST (body
)) == SIGN_EXTRACT
2555 || GET_CODE (SET_DEST (body
)) == ZERO_EXTRACT
)
2556 bitfield
= SET_DEST (body
), destflag
= 1;
2558 bitfield
= SET_SRC (body
), destflag
= 0;
2560 /* First check that the field being stored has constant size and position
2561 and is in fact a byte or halfword suitably aligned. */
2563 if (GET_CODE (XEXP (bitfield
, 1)) == CONST_INT
2564 && GET_CODE (XEXP (bitfield
, 2)) == CONST_INT
2565 && ((mode
= mode_for_size (INTVAL (XEXP (bitfield
, 1)), MODE_INT
, 1))
2567 && INTVAL (XEXP (bitfield
, 2)) % INTVAL (XEXP (bitfield
, 1)) == 0)
2569 register rtx memref
= 0;
2571 /* Now check that the containing word is memory, not a register,
2572 and that it is safe to change the machine mode. */
2574 if (GET_CODE (XEXP (bitfield
, 0)) == MEM
)
2575 memref
= XEXP (bitfield
, 0);
2576 else if (GET_CODE (XEXP (bitfield
, 0)) == REG
2578 memref
= equiv_mem
[REGNO (XEXP (bitfield
, 0))];
2579 else if (GET_CODE (XEXP (bitfield
, 0)) == SUBREG
2580 && GET_CODE (SUBREG_REG (XEXP (bitfield
, 0))) == MEM
)
2581 memref
= SUBREG_REG (XEXP (bitfield
, 0));
2582 else if (GET_CODE (XEXP (bitfield
, 0)) == SUBREG
2584 && GET_CODE (SUBREG_REG (XEXP (bitfield
, 0))) == REG
)
2585 memref
= equiv_mem
[REGNO (SUBREG_REG (XEXP (bitfield
, 0)))];
2588 && ! mode_dependent_address_p (XEXP (memref
, 0))
2589 && ! MEM_VOLATILE_P (memref
))
2591 /* Now adjust the address, first for any subreg'ing
2592 that we are now getting rid of,
2593 and then for which byte of the word is wanted. */
2595 HOST_WIDE_INT offset
= INTVAL (XEXP (bitfield
, 2));
2598 /* Adjust OFFSET to count bits from low-address byte. */
2599 if (BITS_BIG_ENDIAN
!= BYTES_BIG_ENDIAN
)
2600 offset
= (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield
, 0)))
2601 - offset
- INTVAL (XEXP (bitfield
, 1)));
2603 /* Adjust OFFSET to count bytes from low-address byte. */
2604 offset
/= BITS_PER_UNIT
;
2605 if (GET_CODE (XEXP (bitfield
, 0)) == SUBREG
)
2607 offset
+= SUBREG_WORD (XEXP (bitfield
, 0)) * UNITS_PER_WORD
;
2608 if (BYTES_BIG_ENDIAN
)
2609 offset
-= (MIN (UNITS_PER_WORD
,
2610 GET_MODE_SIZE (GET_MODE (XEXP (bitfield
, 0))))
2611 - MIN (UNITS_PER_WORD
,
2612 GET_MODE_SIZE (GET_MODE (memref
))));
2616 memref
= change_address (memref
, mode
,
2617 plus_constant (XEXP (memref
, 0), offset
));
2618 insns
= get_insns ();
2620 emit_insns_before (insns
, insn
);
2622 /* Store this memory reference where
2623 we found the bit field reference. */
2627 validate_change (insn
, &SET_DEST (body
), memref
, 1);
2628 if (! CONSTANT_ADDRESS_P (SET_SRC (body
)))
2630 rtx src
= SET_SRC (body
);
2631 while (GET_CODE (src
) == SUBREG
2632 && SUBREG_WORD (src
) == 0)
2633 src
= SUBREG_REG (src
);
2634 if (GET_MODE (src
) != GET_MODE (memref
))
2635 src
= gen_lowpart (GET_MODE (memref
), SET_SRC (body
));
2636 validate_change (insn
, &SET_SRC (body
), src
, 1);
2638 else if (GET_MODE (SET_SRC (body
)) != VOIDmode
2639 && GET_MODE (SET_SRC (body
)) != GET_MODE (memref
))
2640 /* This shouldn't happen because anything that didn't have
2641 one of these modes should have got converted explicitly
2642 and then referenced through a subreg.
2643 This is so because the original bit-field was
2644 handled by agg_mode and so its tree structure had
2645 the same mode that memref now has. */
2650 rtx dest
= SET_DEST (body
);
2652 while (GET_CODE (dest
) == SUBREG
2653 && SUBREG_WORD (dest
) == 0
2654 && (GET_MODE_CLASS (GET_MODE (dest
))
2655 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest
)))))
2656 dest
= SUBREG_REG (dest
);
2658 validate_change (insn
, &SET_DEST (body
), dest
, 1);
2660 if (GET_MODE (dest
) == GET_MODE (memref
))
2661 validate_change (insn
, &SET_SRC (body
), memref
, 1);
2664 /* Convert the mem ref to the destination mode. */
2665 rtx newreg
= gen_reg_rtx (GET_MODE (dest
));
2668 convert_move (newreg
, memref
,
2669 GET_CODE (SET_SRC (body
)) == ZERO_EXTRACT
);
2673 validate_change (insn
, &SET_SRC (body
), newreg
, 1);
2677 /* See if we can convert this extraction or insertion into
2678 a simple move insn. We might not be able to do so if this
2679 was, for example, part of a PARALLEL.
2681 If we succeed, write out any needed conversions. If we fail,
2682 it is hard to guess why we failed, so don't do anything
2683 special; just let the optimization be suppressed. */
2685 if (apply_change_group () && seq
)
2686 emit_insns_before (seq
, insn
);
2691 /* These routines are responsible for converting virtual register references
2692 to the actual hard register references once RTL generation is complete.
2694 The following four variables are used for communication between the
2695 routines. They contain the offsets of the virtual registers from their
2696 respective hard registers. */
2698 static int in_arg_offset
;
2699 static int var_offset
;
2700 static int dynamic_offset
;
2701 static int out_arg_offset
;
2702 static int cfa_offset
;
2704 /* In most machines, the stack pointer register is equivalent to the bottom
2707 #ifndef STACK_POINTER_OFFSET
2708 #define STACK_POINTER_OFFSET 0
2711 /* If not defined, pick an appropriate default for the offset of dynamically
2712 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2713 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2715 #ifndef STACK_DYNAMIC_OFFSET
2717 #ifdef ACCUMULATE_OUTGOING_ARGS
2718 /* The bottom of the stack points to the actual arguments. If
2719 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2720 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2721 stack space for register parameters is not pushed by the caller, but
2722 rather part of the fixed stack areas and hence not included in
2723 `current_function_outgoing_args_size'. Nevertheless, we must allow
2724 for it when allocating stack dynamic objects. */
2726 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2727 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2728 (current_function_outgoing_args_size \
2729 + REG_PARM_STACK_SPACE (FNDECL) + (STACK_POINTER_OFFSET))
2732 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2733 (current_function_outgoing_args_size + (STACK_POINTER_OFFSET))
2737 #define STACK_DYNAMIC_OFFSET(FNDECL) STACK_POINTER_OFFSET
2741 /* On a few machines, the CFA coincides with the arg pointer. */
2743 #ifndef ARG_POINTER_CFA_OFFSET
2744 #define ARG_POINTER_CFA_OFFSET 0
2748 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just had
2749 its address taken. DECL is the decl for the object stored in the
2750 register, for later use if we do need to force REG into the stack.
2751 REG is overwritten by the MEM like in put_reg_into_stack. */
2754 gen_mem_addressof (reg
, decl
)
2758 tree type
= TREE_TYPE (decl
);
2759 rtx r
= gen_rtx_ADDRESSOF (Pmode
, gen_reg_rtx (GET_MODE (reg
)), REGNO (reg
));
2760 SET_ADDRESSOF_DECL (r
, decl
);
2761 /* If the original REG was a user-variable, then so is the REG whose
2762 address is being taken. */
2763 REG_USERVAR_P (XEXP (r
, 0)) = REG_USERVAR_P (reg
);
2766 PUT_CODE (reg
, MEM
);
2767 PUT_MODE (reg
, DECL_MODE (decl
));
2768 MEM_VOLATILE_P (reg
) = TREE_SIDE_EFFECTS (decl
);
2769 MEM_IN_STRUCT_P (reg
) = AGGREGATE_TYPE_P (type
);
2770 MEM_ALIAS_SET (reg
) = get_alias_set (decl
);
2772 if (TREE_USED (decl
) || DECL_INITIAL (decl
) != 0)
2773 fixup_var_refs (reg
, GET_MODE (reg
), TREE_UNSIGNED (type
));
2778 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2781 flush_addressof (decl
)
2784 if ((TREE_CODE (decl
) == PARM_DECL
|| TREE_CODE (decl
) == VAR_DECL
)
2785 && DECL_RTL (decl
) != 0
2786 && GET_CODE (DECL_RTL (decl
)) == MEM
2787 && GET_CODE (XEXP (DECL_RTL (decl
), 0)) == ADDRESSOF
2788 && GET_CODE (XEXP (XEXP (DECL_RTL (decl
), 0), 0)) == REG
)
2789 put_addressof_into_stack (XEXP (DECL_RTL (decl
), 0));
2792 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2795 put_addressof_into_stack (r
)
2798 tree decl
= ADDRESSOF_DECL (r
);
2799 rtx reg
= XEXP (r
, 0);
2801 if (GET_CODE (reg
) != REG
)
2804 put_reg_into_stack (0, reg
, TREE_TYPE (decl
), GET_MODE (reg
),
2805 DECL_MODE (decl
), TREE_SIDE_EFFECTS (decl
),
2806 ADDRESSOF_REGNO (r
),
2807 TREE_USED (decl
) || DECL_INITIAL (decl
) != 0);
2810 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2811 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2815 purge_addressof_1 (loc
, insn
, force
)
2825 /* Re-start here to avoid recursion in common cases. */
2832 code
= GET_CODE (x
);
2834 if (code
== ADDRESSOF
&& GET_CODE (XEXP (x
, 0)) == MEM
)
2837 /* We must create a copy of the rtx because it was created by
2838 overwriting a REG rtx which is always shared. */
2839 rtx sub
= copy_rtx (XEXP (XEXP (x
, 0), 0));
2841 if (validate_change (insn
, loc
, sub
, 0))
2845 if (! validate_change (insn
, loc
,
2846 force_operand (sub
, NULL_RTX
),
2850 insns
= get_insns ();
2852 emit_insns_before (insns
, insn
);
2855 else if (code
== MEM
&& GET_CODE (XEXP (x
, 0)) == ADDRESSOF
&& ! force
)
2857 rtx sub
= XEXP (XEXP (x
, 0), 0);
2859 if (GET_CODE (sub
) == MEM
)
2860 sub
= gen_rtx_MEM (GET_MODE (x
), copy_rtx (XEXP (sub
, 0)));
2862 if (GET_CODE (sub
) == REG
2863 && (MEM_VOLATILE_P (x
) || GET_MODE (x
) == BLKmode
))
2865 put_addressof_into_stack (XEXP (x
, 0));
2868 else if (GET_CODE (sub
) == REG
&& GET_MODE (x
) != GET_MODE (sub
))
2870 if (! BYTES_BIG_ENDIAN
&& ! WORDS_BIG_ENDIAN
)
2872 rtx sub2
= gen_rtx_SUBREG (GET_MODE (x
), sub
, 0);
2873 if (validate_change (insn
, loc
, sub2
, 0))
2877 else if (validate_change (insn
, loc
, sub
, 0))
2879 /* else give up and put it into the stack */
2881 else if (code
== ADDRESSOF
)
2883 put_addressof_into_stack (x
);
2887 /* Scan all subexpressions. */
2888 fmt
= GET_RTX_FORMAT (code
);
2889 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
2892 purge_addressof_1 (&XEXP (x
, i
), insn
, force
);
2893 else if (*fmt
== 'E')
2894 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
2895 purge_addressof_1 (&XVECEXP (x
, i
, j
), insn
, force
);
2899 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
2900 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
2904 purge_addressof (insns
)
2908 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
2909 if (GET_CODE (insn
) == INSN
|| GET_CODE (insn
) == JUMP_INSN
2910 || GET_CODE (insn
) == CALL_INSN
)
2912 purge_addressof_1 (&PATTERN (insn
), insn
,
2913 asm_noperands (PATTERN (insn
)) > 0);
2914 purge_addressof_1 (®_NOTES (insn
), NULL_RTX
, 0);
2918 /* Pass through the INSNS of function FNDECL and convert virtual register
2919 references to hard register references. */
2922 instantiate_virtual_regs (fndecl
, insns
)
2929 /* Compute the offsets to use for this function. */
2930 in_arg_offset
= FIRST_PARM_OFFSET (fndecl
);
2931 var_offset
= STARTING_FRAME_OFFSET
;
2932 dynamic_offset
= STACK_DYNAMIC_OFFSET (fndecl
);
2933 out_arg_offset
= STACK_POINTER_OFFSET
;
2934 cfa_offset
= ARG_POINTER_CFA_OFFSET
;
2936 /* Scan all variables and parameters of this function. For each that is
2937 in memory, instantiate all virtual registers if the result is a valid
2938 address. If not, we do it later. That will handle most uses of virtual
2939 regs on many machines. */
2940 instantiate_decls (fndecl
, 1);
2942 /* Initialize recognition, indicating that volatile is OK. */
2945 /* Scan through all the insns, instantiating every virtual register still
2947 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
2948 if (GET_CODE (insn
) == INSN
|| GET_CODE (insn
) == JUMP_INSN
2949 || GET_CODE (insn
) == CALL_INSN
)
2951 instantiate_virtual_regs_1 (&PATTERN (insn
), insn
, 1);
2952 instantiate_virtual_regs_1 (®_NOTES (insn
), NULL_RTX
, 0);
2955 /* Instantiate the stack slots for the parm registers, for later use in
2956 addressof elimination. */
2957 for (i
= 0; i
< max_parm_reg
; ++i
)
2958 if (parm_reg_stack_loc
[i
])
2959 instantiate_virtual_regs_1 (&parm_reg_stack_loc
[i
], NULL_RTX
, 0);
2961 /* Now instantiate the remaining register equivalences for debugging info.
2962 These will not be valid addresses. */
2963 instantiate_decls (fndecl
, 0);
2965 /* Indicate that, from now on, assign_stack_local should use
2966 frame_pointer_rtx. */
2967 virtuals_instantiated
= 1;
2970 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
2971 all virtual registers in their DECL_RTL's.
2973 If VALID_ONLY, do this only if the resulting address is still valid.
2974 Otherwise, always do it. */
2977 instantiate_decls (fndecl
, valid_only
)
2983 if (DECL_SAVED_INSNS (fndecl
))
2984 /* When compiling an inline function, the obstack used for
2985 rtl allocation is the maybepermanent_obstack. Calling
2986 `resume_temporary_allocation' switches us back to that
2987 obstack while we process this function's parameters. */
2988 resume_temporary_allocation ();
2990 /* Process all parameters of the function. */
2991 for (decl
= DECL_ARGUMENTS (fndecl
); decl
; decl
= TREE_CHAIN (decl
))
2993 HOST_WIDE_INT size
= int_size_in_bytes (TREE_TYPE (decl
));
2995 instantiate_decl (DECL_RTL (decl
), size
, valid_only
);
2997 /* If the parameter was promoted, then the incoming RTL mode may be
2998 larger than the declared type size. We must use the larger of
3000 size
= MAX (GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl
))), size
);
3001 instantiate_decl (DECL_INCOMING_RTL (decl
), size
, valid_only
);
3004 /* Now process all variables defined in the function or its subblocks. */
3005 instantiate_decls_1 (DECL_INITIAL (fndecl
), valid_only
);
3007 if (DECL_INLINE (fndecl
) || DECL_DEFER_OUTPUT (fndecl
))
3009 /* Save all rtl allocated for this function by raising the
3010 high-water mark on the maybepermanent_obstack. */
3012 /* All further rtl allocation is now done in the current_obstack. */
3013 rtl_in_current_obstack ();
3017 /* Subroutine of instantiate_decls: Process all decls in the given
3018 BLOCK node and all its subblocks. */
3021 instantiate_decls_1 (let
, valid_only
)
3027 for (t
= BLOCK_VARS (let
); t
; t
= TREE_CHAIN (t
))
3028 instantiate_decl (DECL_RTL (t
), int_size_in_bytes (TREE_TYPE (t
)),
3031 /* Process all subblocks. */
3032 for (t
= BLOCK_SUBBLOCKS (let
); t
; t
= TREE_CHAIN (t
))
3033 instantiate_decls_1 (t
, valid_only
);
3036 /* Subroutine of the preceding procedures: Given RTL representing a
3037 decl and the size of the object, do any instantiation required.
3039 If VALID_ONLY is non-zero, it means that the RTL should only be
3040 changed if the new address is valid. */
3043 instantiate_decl (x
, size
, valid_only
)
3048 enum machine_mode mode
;
3051 /* If this is not a MEM, no need to do anything. Similarly if the
3052 address is a constant or a register that is not a virtual register. */
3054 if (x
== 0 || GET_CODE (x
) != MEM
)
3058 if (CONSTANT_P (addr
)
3059 || (GET_CODE (addr
) == ADDRESSOF
&& GET_CODE (XEXP (addr
, 0)) == REG
)
3060 || (GET_CODE (addr
) == REG
3061 && (REGNO (addr
) < FIRST_VIRTUAL_REGISTER
3062 || REGNO (addr
) > LAST_VIRTUAL_REGISTER
)))
3065 /* If we should only do this if the address is valid, copy the address.
3066 We need to do this so we can undo any changes that might make the
3067 address invalid. This copy is unfortunate, but probably can't be
3071 addr
= copy_rtx (addr
);
3073 instantiate_virtual_regs_1 (&addr
, NULL_RTX
, 0);
3077 /* Now verify that the resulting address is valid for every integer or
3078 floating-point mode up to and including SIZE bytes long. We do this
3079 since the object might be accessed in any mode and frame addresses
3082 for (mode
= GET_CLASS_NARROWEST_MODE (MODE_INT
);
3083 mode
!= VOIDmode
&& GET_MODE_SIZE (mode
) <= size
;
3084 mode
= GET_MODE_WIDER_MODE (mode
))
3085 if (! memory_address_p (mode
, addr
))
3088 for (mode
= GET_CLASS_NARROWEST_MODE (MODE_FLOAT
);
3089 mode
!= VOIDmode
&& GET_MODE_SIZE (mode
) <= size
;
3090 mode
= GET_MODE_WIDER_MODE (mode
))
3091 if (! memory_address_p (mode
, addr
))
3095 /* Put back the address now that we have updated it and we either know
3096 it is valid or we don't care whether it is valid. */
3101 /* Given a pointer to a piece of rtx and an optional pointer to the
3102 containing object, instantiate any virtual registers present in it.
3104 If EXTRA_INSNS, we always do the replacement and generate
3105 any extra insns before OBJECT. If it zero, we do nothing if replacement
3108 Return 1 if we either had nothing to do or if we were able to do the
3109 needed replacement. Return 0 otherwise; we only return zero if
3110 EXTRA_INSNS is zero.
3112 We first try some simple transformations to avoid the creation of extra
3116 instantiate_virtual_regs_1 (loc
, object
, extra_insns
)
3124 HOST_WIDE_INT offset
;
3130 /* Re-start here to avoid recursion in common cases. */
3137 code
= GET_CODE (x
);
3139 /* Check for some special cases. */
3156 /* We are allowed to set the virtual registers. This means that
3157 the actual register should receive the source minus the
3158 appropriate offset. This is used, for example, in the handling
3159 of non-local gotos. */
3160 if (SET_DEST (x
) == virtual_incoming_args_rtx
)
3161 new = arg_pointer_rtx
, offset
= - in_arg_offset
;
3162 else if (SET_DEST (x
) == virtual_stack_vars_rtx
)
3163 new = frame_pointer_rtx
, offset
= - var_offset
;
3164 else if (SET_DEST (x
) == virtual_stack_dynamic_rtx
)
3165 new = stack_pointer_rtx
, offset
= - dynamic_offset
;
3166 else if (SET_DEST (x
) == virtual_outgoing_args_rtx
)
3167 new = stack_pointer_rtx
, offset
= - out_arg_offset
;
3168 else if (SET_DEST (x
) == virtual_cfa_rtx
)
3169 new = arg_pointer_rtx
, offset
= - cfa_offset
;
3173 /* The only valid sources here are PLUS or REG. Just do
3174 the simplest possible thing to handle them. */
3175 if (GET_CODE (SET_SRC (x
)) != REG
3176 && GET_CODE (SET_SRC (x
)) != PLUS
)
3180 if (GET_CODE (SET_SRC (x
)) != REG
)
3181 temp
= force_operand (SET_SRC (x
), NULL_RTX
);
3184 temp
= force_operand (plus_constant (temp
, offset
), NULL_RTX
);
3188 emit_insns_before (seq
, object
);
3191 if (! validate_change (object
, &SET_SRC (x
), temp
, 0)
3198 instantiate_virtual_regs_1 (&SET_DEST (x
), object
, extra_insns
);
3203 /* Handle special case of virtual register plus constant. */
3204 if (CONSTANT_P (XEXP (x
, 1)))
3206 rtx old
, new_offset
;
3208 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3209 if (GET_CODE (XEXP (x
, 0)) == PLUS
)
3211 rtx inner
= XEXP (XEXP (x
, 0), 0);
3213 if (inner
== virtual_incoming_args_rtx
)
3214 new = arg_pointer_rtx
, offset
= in_arg_offset
;
3215 else if (inner
== virtual_stack_vars_rtx
)
3216 new = frame_pointer_rtx
, offset
= var_offset
;
3217 else if (inner
== virtual_stack_dynamic_rtx
)
3218 new = stack_pointer_rtx
, offset
= dynamic_offset
;
3219 else if (inner
== virtual_outgoing_args_rtx
)
3220 new = stack_pointer_rtx
, offset
= out_arg_offset
;
3221 else if (inner
== virtual_cfa_rtx
)
3222 new = arg_pointer_rtx
, offset
= cfa_offset
;
3229 instantiate_virtual_regs_1 (&XEXP (XEXP (x
, 0), 1), object
,
3231 new = gen_rtx_PLUS (Pmode
, new, XEXP (XEXP (x
, 0), 1));
3234 else if (XEXP (x
, 0) == virtual_incoming_args_rtx
)
3235 new = arg_pointer_rtx
, offset
= in_arg_offset
;
3236 else if (XEXP (x
, 0) == virtual_stack_vars_rtx
)
3237 new = frame_pointer_rtx
, offset
= var_offset
;
3238 else if (XEXP (x
, 0) == virtual_stack_dynamic_rtx
)
3239 new = stack_pointer_rtx
, offset
= dynamic_offset
;
3240 else if (XEXP (x
, 0) == virtual_outgoing_args_rtx
)
3241 new = stack_pointer_rtx
, offset
= out_arg_offset
;
3242 else if (XEXP (x
, 0) == virtual_cfa_rtx
)
3243 new = arg_pointer_rtx
, offset
= cfa_offset
;
3246 /* We know the second operand is a constant. Unless the
3247 first operand is a REG (which has been already checked),
3248 it needs to be checked. */
3249 if (GET_CODE (XEXP (x
, 0)) != REG
)
3257 new_offset
= plus_constant (XEXP (x
, 1), offset
);
3259 /* If the new constant is zero, try to replace the sum with just
3261 if (new_offset
== const0_rtx
3262 && validate_change (object
, loc
, new, 0))
3265 /* Next try to replace the register and new offset.
3266 There are two changes to validate here and we can't assume that
3267 in the case of old offset equals new just changing the register
3268 will yield a valid insn. In the interests of a little efficiency,
3269 however, we only call validate change once (we don't queue up the
3270 changes and then call apply_change_group). */
3274 ? ! validate_change (object
, &XEXP (x
, 0), new, 0)
3275 : (XEXP (x
, 0) = new,
3276 ! validate_change (object
, &XEXP (x
, 1), new_offset
, 0)))
3284 /* Otherwise copy the new constant into a register and replace
3285 constant with that register. */
3286 temp
= gen_reg_rtx (Pmode
);
3288 if (validate_change (object
, &XEXP (x
, 1), temp
, 0))
3289 emit_insn_before (gen_move_insn (temp
, new_offset
), object
);
3292 /* If that didn't work, replace this expression with a
3293 register containing the sum. */
3296 new = gen_rtx_PLUS (Pmode
, new, new_offset
);
3299 temp
= force_operand (new, NULL_RTX
);
3303 emit_insns_before (seq
, object
);
3304 if (! validate_change (object
, loc
, temp
, 0)
3305 && ! validate_replace_rtx (x
, temp
, object
))
3313 /* Fall through to generic two-operand expression case. */
3319 case DIV
: case UDIV
:
3320 case MOD
: case UMOD
:
3321 case AND
: case IOR
: case XOR
:
3322 case ROTATERT
: case ROTATE
:
3323 case ASHIFTRT
: case LSHIFTRT
: case ASHIFT
:
3325 case GE
: case GT
: case GEU
: case GTU
:
3326 case LE
: case LT
: case LEU
: case LTU
:
3327 if (XEXP (x
, 1) && ! CONSTANT_P (XEXP (x
, 1)))
3328 instantiate_virtual_regs_1 (&XEXP (x
, 1), object
, extra_insns
);
3333 /* Most cases of MEM that convert to valid addresses have already been
3334 handled by our scan of decls. The only special handling we
3335 need here is to make a copy of the rtx to ensure it isn't being
3336 shared if we have to change it to a pseudo.
3338 If the rtx is a simple reference to an address via a virtual register,
3339 it can potentially be shared. In such cases, first try to make it
3340 a valid address, which can also be shared. Otherwise, copy it and
3343 First check for common cases that need no processing. These are
3344 usually due to instantiation already being done on a previous instance
3348 if (CONSTANT_ADDRESS_P (temp
)
3349 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3350 || temp
== arg_pointer_rtx
3352 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3353 || temp
== hard_frame_pointer_rtx
3355 || temp
== frame_pointer_rtx
)
3358 if (GET_CODE (temp
) == PLUS
3359 && CONSTANT_ADDRESS_P (XEXP (temp
, 1))
3360 && (XEXP (temp
, 0) == frame_pointer_rtx
3361 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3362 || XEXP (temp
, 0) == hard_frame_pointer_rtx
3364 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3365 || XEXP (temp
, 0) == arg_pointer_rtx
3370 if (temp
== virtual_stack_vars_rtx
3371 || temp
== virtual_incoming_args_rtx
3372 || (GET_CODE (temp
) == PLUS
3373 && CONSTANT_ADDRESS_P (XEXP (temp
, 1))
3374 && (XEXP (temp
, 0) == virtual_stack_vars_rtx
3375 || XEXP (temp
, 0) == virtual_incoming_args_rtx
)))
3377 /* This MEM may be shared. If the substitution can be done without
3378 the need to generate new pseudos, we want to do it in place
3379 so all copies of the shared rtx benefit. The call below will
3380 only make substitutions if the resulting address is still
3383 Note that we cannot pass X as the object in the recursive call
3384 since the insn being processed may not allow all valid
3385 addresses. However, if we were not passed on object, we can
3386 only modify X without copying it if X will have a valid
3389 ??? Also note that this can still lose if OBJECT is an insn that
3390 has less restrictions on an address that some other insn.
3391 In that case, we will modify the shared address. This case
3392 doesn't seem very likely, though. One case where this could
3393 happen is in the case of a USE or CLOBBER reference, but we
3394 take care of that below. */
3396 if (instantiate_virtual_regs_1 (&XEXP (x
, 0),
3397 object
? object
: x
, 0))
3400 /* Otherwise make a copy and process that copy. We copy the entire
3401 RTL expression since it might be a PLUS which could also be
3403 *loc
= x
= copy_rtx (x
);
3406 /* Fall through to generic unary operation case. */
3408 case STRICT_LOW_PART
:
3410 case PRE_DEC
: case PRE_INC
: case POST_DEC
: case POST_INC
:
3411 case SIGN_EXTEND
: case ZERO_EXTEND
:
3412 case TRUNCATE
: case FLOAT_EXTEND
: case FLOAT_TRUNCATE
:
3413 case FLOAT
: case FIX
:
3414 case UNSIGNED_FIX
: case UNSIGNED_FLOAT
:
3418 /* These case either have just one operand or we know that we need not
3419 check the rest of the operands. */
3425 /* If the operand is a MEM, see if the change is a valid MEM. If not,
3426 go ahead and make the invalid one, but do it to a copy. For a REG,
3427 just make the recursive call, since there's no chance of a problem. */
3429 if ((GET_CODE (XEXP (x
, 0)) == MEM
3430 && instantiate_virtual_regs_1 (&XEXP (XEXP (x
, 0), 0), XEXP (x
, 0),
3432 || (GET_CODE (XEXP (x
, 0)) == REG
3433 && instantiate_virtual_regs_1 (&XEXP (x
, 0), object
, 0)))
3436 XEXP (x
, 0) = copy_rtx (XEXP (x
, 0));
3441 /* Try to replace with a PLUS. If that doesn't work, compute the sum
3442 in front of this insn and substitute the temporary. */
3443 if (x
== virtual_incoming_args_rtx
)
3444 new = arg_pointer_rtx
, offset
= in_arg_offset
;
3445 else if (x
== virtual_stack_vars_rtx
)
3446 new = frame_pointer_rtx
, offset
= var_offset
;
3447 else if (x
== virtual_stack_dynamic_rtx
)
3448 new = stack_pointer_rtx
, offset
= dynamic_offset
;
3449 else if (x
== virtual_outgoing_args_rtx
)
3450 new = stack_pointer_rtx
, offset
= out_arg_offset
;
3451 else if (x
== virtual_cfa_rtx
)
3452 new = arg_pointer_rtx
, offset
= cfa_offset
;
3456 temp
= plus_constant (new, offset
);
3457 if (!validate_change (object
, loc
, temp
, 0))
3463 temp
= force_operand (temp
, NULL_RTX
);
3467 emit_insns_before (seq
, object
);
3468 if (! validate_change (object
, loc
, temp
, 0)
3469 && ! validate_replace_rtx (x
, temp
, object
))
3477 if (GET_CODE (XEXP (x
, 0)) == REG
)
3480 else if (GET_CODE (XEXP (x
, 0)) == MEM
)
3482 /* If we have a (addressof (mem ..)), do any instantiation inside
3483 since we know we'll be making the inside valid when we finally
3484 remove the ADDRESSOF. */
3485 instantiate_virtual_regs_1 (&XEXP (XEXP (x
, 0), 0), NULL_RTX
, 0);
3494 /* Scan all subexpressions. */
3495 fmt
= GET_RTX_FORMAT (code
);
3496 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
3499 if (!instantiate_virtual_regs_1 (&XEXP (x
, i
), object
, extra_insns
))
3502 else if (*fmt
== 'E')
3503 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
3504 if (! instantiate_virtual_regs_1 (&XVECEXP (x
, i
, j
), object
,
3511 /* Optimization: assuming this function does not receive nonlocal gotos,
3512 delete the handlers for such, as well as the insns to establish
3513 and disestablish them. */
3519 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
3521 /* Delete the handler by turning off the flag that would
3522 prevent jump_optimize from deleting it.
3523 Also permit deletion of the nonlocal labels themselves
3524 if nothing local refers to them. */
3525 if (GET_CODE (insn
) == CODE_LABEL
)
3529 LABEL_PRESERVE_P (insn
) = 0;
3531 /* Remove it from the nonlocal_label list, to avoid confusing
3533 for (t
= nonlocal_labels
, last_t
= 0; t
;
3534 last_t
= t
, t
= TREE_CHAIN (t
))
3535 if (DECL_RTL (TREE_VALUE (t
)) == insn
)
3540 nonlocal_labels
= TREE_CHAIN (nonlocal_labels
);
3542 TREE_CHAIN (last_t
) = TREE_CHAIN (t
);
3545 if (GET_CODE (insn
) == INSN
3546 && ((nonlocal_goto_handler_slot
!= 0
3547 && reg_mentioned_p (nonlocal_goto_handler_slot
, PATTERN (insn
)))
3548 || (nonlocal_goto_stack_level
!= 0
3549 && reg_mentioned_p (nonlocal_goto_stack_level
,
3555 /* Return a list (chain of EXPR_LIST nodes) for the nonlocal labels
3556 of the current function. */
3559 nonlocal_label_rtx_list ()
3564 for (t
= nonlocal_labels
; t
; t
= TREE_CHAIN (t
))
3565 x
= gen_rtx_EXPR_LIST (VOIDmode
, label_rtx (TREE_VALUE (t
)), x
);
3570 /* Output a USE for any register use in RTL.
3571 This is used with -noreg to mark the extent of lifespan
3572 of any registers used in a user-visible variable's DECL_RTL. */
3578 if (GET_CODE (rtl
) == REG
)
3579 /* This is a register variable. */
3580 emit_insn (gen_rtx_USE (VOIDmode
, rtl
));
3581 else if (GET_CODE (rtl
) == MEM
3582 && GET_CODE (XEXP (rtl
, 0)) == REG
3583 && (REGNO (XEXP (rtl
, 0)) < FIRST_VIRTUAL_REGISTER
3584 || REGNO (XEXP (rtl
, 0)) > LAST_VIRTUAL_REGISTER
)
3585 && XEXP (rtl
, 0) != current_function_internal_arg_pointer
)
3586 /* This is a variable-sized structure. */
3587 emit_insn (gen_rtx_USE (VOIDmode
, XEXP (rtl
, 0)));
3590 /* Like use_variable except that it outputs the USEs after INSN
3591 instead of at the end of the insn-chain. */
3594 use_variable_after (rtl
, insn
)
3597 if (GET_CODE (rtl
) == REG
)
3598 /* This is a register variable. */
3599 emit_insn_after (gen_rtx_USE (VOIDmode
, rtl
), insn
);
3600 else if (GET_CODE (rtl
) == MEM
3601 && GET_CODE (XEXP (rtl
, 0)) == REG
3602 && (REGNO (XEXP (rtl
, 0)) < FIRST_VIRTUAL_REGISTER
3603 || REGNO (XEXP (rtl
, 0)) > LAST_VIRTUAL_REGISTER
)
3604 && XEXP (rtl
, 0) != current_function_internal_arg_pointer
)
3605 /* This is a variable-sized structure. */
3606 emit_insn_after (gen_rtx_USE (VOIDmode
, XEXP (rtl
, 0)), insn
);
3612 return max_parm_reg
;
3615 /* Return the first insn following those generated by `assign_parms'. */
3618 get_first_nonparm_insn ()
3621 return NEXT_INSN (last_parm_insn
);
3622 return get_insns ();
3625 /* Return the first NOTE_INSN_BLOCK_BEG note in the function.
3626 Crash if there is none. */
3629 get_first_block_beg ()
3631 register rtx searcher
;
3632 register rtx insn
= get_first_nonparm_insn ();
3634 for (searcher
= insn
; searcher
; searcher
= NEXT_INSN (searcher
))
3635 if (GET_CODE (searcher
) == NOTE
3636 && NOTE_LINE_NUMBER (searcher
) == NOTE_INSN_BLOCK_BEG
)
3639 abort (); /* Invalid call to this function. (See comments above.) */
3643 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
3644 This means a type for which function calls must pass an address to the
3645 function or get an address back from the function.
3646 EXP may be a type node or an expression (whose type is tested). */
3649 aggregate_value_p (exp
)
3652 int i
, regno
, nregs
;
3655 if (TREE_CODE_CLASS (TREE_CODE (exp
)) == 't')
3658 type
= TREE_TYPE (exp
);
3660 if (RETURN_IN_MEMORY (type
))
3662 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
3663 and thus can't be returned in registers. */
3664 if (TREE_ADDRESSABLE (type
))
3666 if (flag_pcc_struct_return
&& AGGREGATE_TYPE_P (type
))
3668 /* Make sure we have suitable call-clobbered regs to return
3669 the value in; if not, we must return it in memory. */
3670 reg
= hard_function_value (type
, 0);
3672 /* If we have something other than a REG (e.g. a PARALLEL), then assume
3674 if (GET_CODE (reg
) != REG
)
3677 regno
= REGNO (reg
);
3678 nregs
= HARD_REGNO_NREGS (regno
, TYPE_MODE (type
));
3679 for (i
= 0; i
< nregs
; i
++)
3680 if (! call_used_regs
[regno
+ i
])
3685 /* Assign RTL expressions to the function's parameters.
3686 This may involve copying them into registers and using
3687 those registers as the RTL for them.
3689 If SECOND_TIME is non-zero it means that this function is being
3690 called a second time. This is done by integrate.c when a function's
3691 compilation is deferred. We need to come back here in case the
3692 FUNCTION_ARG macro computes items needed for the rest of the compilation
3693 (such as changing which registers are fixed or caller-saved). But suppress
3694 writing any insns or setting DECL_RTL of anything in this case. */
3697 assign_parms (fndecl
, second_time
)
3702 register rtx entry_parm
= 0;
3703 register rtx stack_parm
= 0;
3704 CUMULATIVE_ARGS args_so_far
;
3705 enum machine_mode promoted_mode
, passed_mode
;
3706 enum machine_mode nominal_mode
, promoted_nominal_mode
;
3708 /* Total space needed so far for args on the stack,
3709 given as a constant and a tree-expression. */
3710 struct args_size stack_args_size
;
3711 tree fntype
= TREE_TYPE (fndecl
);
3712 tree fnargs
= DECL_ARGUMENTS (fndecl
);
3713 /* This is used for the arg pointer when referring to stack args. */
3714 rtx internal_arg_pointer
;
3715 /* This is a dummy PARM_DECL that we used for the function result if
3716 the function returns a structure. */
3717 tree function_result_decl
= 0;
3718 int varargs_setup
= 0;
3719 rtx conversion_insns
= 0;
3721 /* Nonzero if the last arg is named `__builtin_va_alist',
3722 which is used on some machines for old-fashioned non-ANSI varargs.h;
3723 this should be stuck onto the stack as if it had arrived there. */
3725 = (current_function_varargs
3727 && (parm
= tree_last (fnargs
)) != 0
3729 && (! strcmp (IDENTIFIER_POINTER (DECL_NAME (parm
)),
3730 "__builtin_va_alist")));
3732 /* Nonzero if function takes extra anonymous args.
3733 This means the last named arg must be on the stack
3734 right before the anonymous ones. */
3736 = (TYPE_ARG_TYPES (fntype
) != 0
3737 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype
)))
3738 != void_type_node
));
3740 current_function_stdarg
= stdarg
;
3742 /* If the reg that the virtual arg pointer will be translated into is
3743 not a fixed reg or is the stack pointer, make a copy of the virtual
3744 arg pointer, and address parms via the copy. The frame pointer is
3745 considered fixed even though it is not marked as such.
3747 The second time through, simply use ap to avoid generating rtx. */
3749 if ((ARG_POINTER_REGNUM
== STACK_POINTER_REGNUM
3750 || ! (fixed_regs
[ARG_POINTER_REGNUM
]
3751 || ARG_POINTER_REGNUM
== FRAME_POINTER_REGNUM
))
3753 internal_arg_pointer
= copy_to_reg (virtual_incoming_args_rtx
);
3755 internal_arg_pointer
= virtual_incoming_args_rtx
;
3756 current_function_internal_arg_pointer
= internal_arg_pointer
;
3758 stack_args_size
.constant
= 0;
3759 stack_args_size
.var
= 0;
3761 /* If struct value address is treated as the first argument, make it so. */
3762 if (aggregate_value_p (DECL_RESULT (fndecl
))
3763 && ! current_function_returns_pcc_struct
3764 && struct_value_incoming_rtx
== 0)
3766 tree type
= build_pointer_type (TREE_TYPE (fntype
));
3768 function_result_decl
= build_decl (PARM_DECL
, NULL_TREE
, type
);
3770 DECL_ARG_TYPE (function_result_decl
) = type
;
3771 TREE_CHAIN (function_result_decl
) = fnargs
;
3772 fnargs
= function_result_decl
;
3775 max_parm_reg
= LAST_VIRTUAL_REGISTER
+ 1;
3776 parm_reg_stack_loc
= (rtx
*) savealloc (max_parm_reg
* sizeof (rtx
));
3777 bzero ((char *) parm_reg_stack_loc
, max_parm_reg
* sizeof (rtx
));
3779 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
3780 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far
, fntype
, NULL_RTX
);
3782 INIT_CUMULATIVE_ARGS (args_so_far
, fntype
, NULL_RTX
, 0);
3785 /* We haven't yet found an argument that we must push and pretend the
3787 current_function_pretend_args_size
= 0;
3789 for (parm
= fnargs
; parm
; parm
= TREE_CHAIN (parm
))
3791 int aggregate
= AGGREGATE_TYPE_P (TREE_TYPE (parm
));
3792 struct args_size stack_offset
;
3793 struct args_size arg_size
;
3794 int passed_pointer
= 0;
3795 int did_conversion
= 0;
3796 tree passed_type
= DECL_ARG_TYPE (parm
);
3797 tree nominal_type
= TREE_TYPE (parm
);
3799 /* Set LAST_NAMED if this is last named arg before some
3801 int last_named
= ((TREE_CHAIN (parm
) == 0
3802 || DECL_NAME (TREE_CHAIN (parm
)) == 0)
3803 && (stdarg
|| current_function_varargs
));
3804 /* Set NAMED_ARG if this arg should be treated as a named arg. For
3805 most machines, if this is a varargs/stdarg function, then we treat
3806 the last named arg as if it were anonymous too. */
3807 int named_arg
= STRICT_ARGUMENT_NAMING
? 1 : ! last_named
;
3809 if (TREE_TYPE (parm
) == error_mark_node
3810 /* This can happen after weird syntax errors
3811 or if an enum type is defined among the parms. */
3812 || TREE_CODE (parm
) != PARM_DECL
3813 || passed_type
== NULL
)
3815 DECL_INCOMING_RTL (parm
) = DECL_RTL (parm
)
3816 = gen_rtx_MEM (BLKmode
, const0_rtx
);
3817 TREE_USED (parm
) = 1;
3821 /* For varargs.h function, save info about regs and stack space
3822 used by the individual args, not including the va_alist arg. */
3823 if (hide_last_arg
&& last_named
)
3824 current_function_args_info
= args_so_far
;
3826 /* Find mode of arg as it is passed, and mode of arg
3827 as it should be during execution of this function. */
3828 passed_mode
= TYPE_MODE (passed_type
);
3829 nominal_mode
= TYPE_MODE (nominal_type
);
3831 /* If the parm's mode is VOID, its value doesn't matter,
3832 and avoid the usual things like emit_move_insn that could crash. */
3833 if (nominal_mode
== VOIDmode
)
3835 DECL_INCOMING_RTL (parm
) = DECL_RTL (parm
) = const0_rtx
;
3839 /* If the parm is to be passed as a transparent union, use the
3840 type of the first field for the tests below. We have already
3841 verified that the modes are the same. */
3842 if (DECL_TRANSPARENT_UNION (parm
)
3843 || TYPE_TRANSPARENT_UNION (passed_type
))
3844 passed_type
= TREE_TYPE (TYPE_FIELDS (passed_type
));
3846 /* See if this arg was passed by invisible reference. It is if
3847 it is an object whose size depends on the contents of the
3848 object itself or if the machine requires these objects be passed
3851 if ((TREE_CODE (TYPE_SIZE (passed_type
)) != INTEGER_CST
3852 && contains_placeholder_p (TYPE_SIZE (passed_type
)))
3853 || TREE_ADDRESSABLE (passed_type
)
3854 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3855 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far
, passed_mode
,
3856 passed_type
, named_arg
)
3860 passed_type
= nominal_type
= build_pointer_type (passed_type
);
3862 passed_mode
= nominal_mode
= Pmode
;
3865 promoted_mode
= passed_mode
;
3867 #ifdef PROMOTE_FUNCTION_ARGS
3868 /* Compute the mode in which the arg is actually extended to. */
3869 unsignedp
= TREE_UNSIGNED (passed_type
);
3870 promoted_mode
= promote_mode (passed_type
, promoted_mode
, &unsignedp
, 1);
3873 /* Let machine desc say which reg (if any) the parm arrives in.
3874 0 means it arrives on the stack. */
3875 #ifdef FUNCTION_INCOMING_ARG
3876 entry_parm
= FUNCTION_INCOMING_ARG (args_so_far
, promoted_mode
,
3877 passed_type
, named_arg
);
3879 entry_parm
= FUNCTION_ARG (args_so_far
, promoted_mode
,
3880 passed_type
, named_arg
);
3883 if (entry_parm
== 0)
3884 promoted_mode
= passed_mode
;
3886 #ifdef SETUP_INCOMING_VARARGS
3887 /* If this is the last named parameter, do any required setup for
3888 varargs or stdargs. We need to know about the case of this being an
3889 addressable type, in which case we skip the registers it
3890 would have arrived in.
3892 For stdargs, LAST_NAMED will be set for two parameters, the one that
3893 is actually the last named, and the dummy parameter. We only
3894 want to do this action once.
3896 Also, indicate when RTL generation is to be suppressed. */
3897 if (last_named
&& !varargs_setup
)
3899 SETUP_INCOMING_VARARGS (args_so_far
, promoted_mode
, passed_type
,
3900 current_function_pretend_args_size
,
3906 /* Determine parm's home in the stack,
3907 in case it arrives in the stack or we should pretend it did.
3909 Compute the stack position and rtx where the argument arrives
3912 There is one complexity here: If this was a parameter that would
3913 have been passed in registers, but wasn't only because it is
3914 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
3915 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
3916 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
3917 0 as it was the previous time. */
3919 locate_and_pad_parm (promoted_mode
, passed_type
,
3920 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3923 #ifdef FUNCTION_INCOMING_ARG
3924 FUNCTION_INCOMING_ARG (args_so_far
, promoted_mode
,
3927 || varargs_setup
)) != 0,
3929 FUNCTION_ARG (args_so_far
, promoted_mode
,
3931 named_arg
|| varargs_setup
) != 0,
3934 fndecl
, &stack_args_size
, &stack_offset
, &arg_size
);
3938 rtx offset_rtx
= ARGS_SIZE_RTX (stack_offset
);
3940 if (offset_rtx
== const0_rtx
)
3941 stack_parm
= gen_rtx_MEM (promoted_mode
, internal_arg_pointer
);
3943 stack_parm
= gen_rtx_MEM (promoted_mode
,
3944 gen_rtx_PLUS (Pmode
,
3945 internal_arg_pointer
,
3948 /* If this is a memory ref that contains aggregate components,
3949 mark it as such for cse and loop optimize. Likewise if it
3951 MEM_IN_STRUCT_P (stack_parm
) = aggregate
;
3952 RTX_UNCHANGING_P (stack_parm
) = TREE_READONLY (parm
);
3953 MEM_ALIAS_SET (stack_parm
) = get_alias_set (parm
);
3956 /* If this parameter was passed both in registers and in the stack,
3957 use the copy on the stack. */
3958 if (MUST_PASS_IN_STACK (promoted_mode
, passed_type
))
3961 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3962 /* If this parm was passed part in regs and part in memory,
3963 pretend it arrived entirely in memory
3964 by pushing the register-part onto the stack.
3966 In the special case of a DImode or DFmode that is split,
3967 we could put it together in a pseudoreg directly,
3968 but for now that's not worth bothering with. */
3972 int nregs
= FUNCTION_ARG_PARTIAL_NREGS (args_so_far
, promoted_mode
,
3973 passed_type
, named_arg
);
3977 current_function_pretend_args_size
3978 = (((nregs
* UNITS_PER_WORD
) + (PARM_BOUNDARY
/ BITS_PER_UNIT
) - 1)
3979 / (PARM_BOUNDARY
/ BITS_PER_UNIT
)
3980 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
3984 /* Handle calls that pass values in multiple non-contiguous
3985 locations. The Irix 6 ABI has examples of this. */
3986 if (GET_CODE (entry_parm
) == PARALLEL
)
3987 emit_group_store (validize_mem (stack_parm
), entry_parm
,
3988 int_size_in_bytes (TREE_TYPE (parm
)),
3989 (TYPE_ALIGN (TREE_TYPE (parm
))
3992 move_block_from_reg (REGNO (entry_parm
),
3993 validize_mem (stack_parm
), nregs
,
3994 int_size_in_bytes (TREE_TYPE (parm
)));
3996 entry_parm
= stack_parm
;
4001 /* If we didn't decide this parm came in a register,
4002 by default it came on the stack. */
4003 if (entry_parm
== 0)
4004 entry_parm
= stack_parm
;
4006 /* Record permanently how this parm was passed. */
4008 DECL_INCOMING_RTL (parm
) = entry_parm
;
4010 /* If there is actually space on the stack for this parm,
4011 count it in stack_args_size; otherwise set stack_parm to 0
4012 to indicate there is no preallocated stack slot for the parm. */
4014 if (entry_parm
== stack_parm
4015 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4016 /* On some machines, even if a parm value arrives in a register
4017 there is still an (uninitialized) stack slot allocated for it.
4019 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4020 whether this parameter already has a stack slot allocated,
4021 because an arg block exists only if current_function_args_size
4022 is larger than some threshold, and we haven't calculated that
4023 yet. So, for now, we just assume that stack slots never exist
4025 || REG_PARM_STACK_SPACE (fndecl
) > 0
4029 stack_args_size
.constant
+= arg_size
.constant
;
4031 ADD_PARM_SIZE (stack_args_size
, arg_size
.var
);
4034 /* No stack slot was pushed for this parm. */
4037 /* Update info on where next arg arrives in registers. */
4039 FUNCTION_ARG_ADVANCE (args_so_far
, promoted_mode
,
4040 passed_type
, named_arg
);
4042 /* If this is our second time through, we are done with this parm. */
4046 /* If we can't trust the parm stack slot to be aligned enough
4047 for its ultimate type, don't use that slot after entry.
4048 We'll make another stack slot, if we need one. */
4050 int thisparm_boundary
4051 = FUNCTION_ARG_BOUNDARY (promoted_mode
, passed_type
);
4053 if (GET_MODE_ALIGNMENT (nominal_mode
) > thisparm_boundary
)
4057 /* If parm was passed in memory, and we need to convert it on entry,
4058 don't store it back in that same slot. */
4060 && nominal_mode
!= BLKmode
&& nominal_mode
!= passed_mode
)
4064 /* Now adjust STACK_PARM to the mode and precise location
4065 where this parameter should live during execution,
4066 if we discover that it must live in the stack during execution.
4067 To make debuggers happier on big-endian machines, we store
4068 the value in the last bytes of the space available. */
4070 if (nominal_mode
!= BLKmode
&& nominal_mode
!= passed_mode
4075 if (BYTES_BIG_ENDIAN
4076 && GET_MODE_SIZE (nominal_mode
) < UNITS_PER_WORD
)
4077 stack_offset
.constant
+= (GET_MODE_SIZE (passed_mode
)
4078 - GET_MODE_SIZE (nominal_mode
));
4080 offset_rtx
= ARGS_SIZE_RTX (stack_offset
);
4081 if (offset_rtx
== const0_rtx
)
4082 stack_parm
= gen_rtx_MEM (nominal_mode
, internal_arg_pointer
);
4084 stack_parm
= gen_rtx_MEM (nominal_mode
,
4085 gen_rtx_PLUS (Pmode
,
4086 internal_arg_pointer
,
4089 /* If this is a memory ref that contains aggregate components,
4090 mark it as such for cse and loop optimize. */
4091 MEM_IN_STRUCT_P (stack_parm
) = aggregate
;
4096 /* We need this "use" info, because the gcc-register->stack-register
4097 converter in reg-stack.c needs to know which registers are active
4098 at the start of the function call. The actual parameter loading
4099 instructions are not always available then anymore, since they might
4100 have been optimised away. */
4102 if (GET_CODE (entry_parm
) == REG
&& !(hide_last_arg
&& last_named
))
4103 emit_insn (gen_rtx_USE (GET_MODE (entry_parm
), entry_parm
));
4106 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4107 in the mode in which it arrives.
4108 STACK_PARM is an RTX for a stack slot where the parameter can live
4109 during the function (in case we want to put it there).
4110 STACK_PARM is 0 if no stack slot was pushed for it.
4112 Now output code if necessary to convert ENTRY_PARM to
4113 the type in which this function declares it,
4114 and store that result in an appropriate place,
4115 which may be a pseudo reg, may be STACK_PARM,
4116 or may be a local stack slot if STACK_PARM is 0.
4118 Set DECL_RTL to that place. */
4120 if (nominal_mode
== BLKmode
|| GET_CODE (entry_parm
) == PARALLEL
)
4122 /* If a BLKmode arrives in registers, copy it to a stack slot.
4123 Handle calls that pass values in multiple non-contiguous
4124 locations. The Irix 6 ABI has examples of this. */
4125 if (GET_CODE (entry_parm
) == REG
4126 || GET_CODE (entry_parm
) == PARALLEL
)
4129 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm
)),
4132 /* Note that we will be storing an integral number of words.
4133 So we have to be careful to ensure that we allocate an
4134 integral number of words. We do this below in the
4135 assign_stack_local if space was not allocated in the argument
4136 list. If it was, this will not work if PARM_BOUNDARY is not
4137 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4138 if it becomes a problem. */
4140 if (stack_parm
== 0)
4143 = assign_stack_local (GET_MODE (entry_parm
),
4146 /* If this is a memory ref that contains aggregate
4147 components, mark it as such for cse and loop optimize. */
4148 MEM_IN_STRUCT_P (stack_parm
) = aggregate
;
4151 else if (PARM_BOUNDARY
% BITS_PER_WORD
!= 0)
4154 if (TREE_READONLY (parm
))
4155 RTX_UNCHANGING_P (stack_parm
) = 1;
4157 /* Handle calls that pass values in multiple non-contiguous
4158 locations. The Irix 6 ABI has examples of this. */
4159 if (GET_CODE (entry_parm
) == PARALLEL
)
4160 emit_group_store (validize_mem (stack_parm
), entry_parm
,
4161 int_size_in_bytes (TREE_TYPE (parm
)),
4162 (TYPE_ALIGN (TREE_TYPE (parm
))
4165 move_block_from_reg (REGNO (entry_parm
),
4166 validize_mem (stack_parm
),
4167 size_stored
/ UNITS_PER_WORD
,
4168 int_size_in_bytes (TREE_TYPE (parm
)));
4170 DECL_RTL (parm
) = stack_parm
;
4172 else if (! ((obey_regdecls
&& ! DECL_REGISTER (parm
)
4173 && ! DECL_INLINE (fndecl
))
4174 /* layout_decl may set this. */
4175 || TREE_ADDRESSABLE (parm
)
4176 || TREE_SIDE_EFFECTS (parm
)
4177 /* If -ffloat-store specified, don't put explicit
4178 float variables into registers. */
4179 || (flag_float_store
4180 && TREE_CODE (TREE_TYPE (parm
)) == REAL_TYPE
))
4181 /* Always assign pseudo to structure return or item passed
4182 by invisible reference. */
4183 || passed_pointer
|| parm
== function_result_decl
)
4185 /* Store the parm in a pseudoregister during the function, but we
4186 may need to do it in a wider mode. */
4188 register rtx parmreg
;
4189 int regno
, regnoi
= 0, regnor
= 0;
4191 unsignedp
= TREE_UNSIGNED (TREE_TYPE (parm
));
4193 promoted_nominal_mode
4194 = promote_mode (TREE_TYPE (parm
), nominal_mode
, &unsignedp
, 0);
4196 parmreg
= gen_reg_rtx (promoted_nominal_mode
);
4197 mark_user_reg (parmreg
);
4199 /* If this was an item that we received a pointer to, set DECL_RTL
4204 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type
)), parmreg
);
4205 MEM_IN_STRUCT_P (DECL_RTL (parm
)) = aggregate
;
4208 DECL_RTL (parm
) = parmreg
;
4210 /* Copy the value into the register. */
4211 if (nominal_mode
!= passed_mode
4212 || promoted_nominal_mode
!= promoted_mode
)
4214 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4215 mode, by the caller. We now have to convert it to
4216 NOMINAL_MODE, if different. However, PARMREG may be in
4217 a different mode than NOMINAL_MODE if it is being stored
4220 If ENTRY_PARM is a hard register, it might be in a register
4221 not valid for operating in its mode (e.g., an odd-numbered
4222 register for a DFmode). In that case, moves are the only
4223 thing valid, so we can't do a convert from there. This
4224 occurs when the calling sequence allow such misaligned
4227 In addition, the conversion may involve a call, which could
4228 clobber parameters which haven't been copied to pseudo
4229 registers yet. Therefore, we must first copy the parm to
4230 a pseudo reg here, and save the conversion until after all
4231 parameters have been moved. */
4233 rtx tempreg
= gen_reg_rtx (GET_MODE (entry_parm
));
4235 emit_move_insn (tempreg
, validize_mem (entry_parm
));
4237 push_to_sequence (conversion_insns
);
4238 tempreg
= convert_to_mode (nominal_mode
, tempreg
, unsignedp
);
4240 expand_assignment (parm
,
4241 make_tree (nominal_type
, tempreg
), 0, 0);
4242 conversion_insns
= get_insns ();
4247 emit_move_insn (parmreg
, validize_mem (entry_parm
));
4249 /* If we were passed a pointer but the actual value
4250 can safely live in a register, put it in one. */
4251 if (passed_pointer
&& TYPE_MODE (TREE_TYPE (parm
)) != BLKmode
4252 && ! ((obey_regdecls
&& ! DECL_REGISTER (parm
)
4253 && ! DECL_INLINE (fndecl
))
4254 /* layout_decl may set this. */
4255 || TREE_ADDRESSABLE (parm
)
4256 || TREE_SIDE_EFFECTS (parm
)
4257 /* If -ffloat-store specified, don't put explicit
4258 float variables into registers. */
4259 || (flag_float_store
4260 && TREE_CODE (TREE_TYPE (parm
)) == REAL_TYPE
)))
4262 /* We can't use nominal_mode, because it will have been set to
4263 Pmode above. We must use the actual mode of the parm. */
4264 parmreg
= gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm
)));
4265 mark_user_reg (parmreg
);
4266 emit_move_insn (parmreg
, DECL_RTL (parm
));
4267 DECL_RTL (parm
) = parmreg
;
4268 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4272 #ifdef FUNCTION_ARG_CALLEE_COPIES
4273 /* If we are passed an arg by reference and it is our responsibility
4274 to make a copy, do it now.
4275 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4276 original argument, so we must recreate them in the call to
4277 FUNCTION_ARG_CALLEE_COPIES. */
4278 /* ??? Later add code to handle the case that if the argument isn't
4279 modified, don't do the copy. */
4281 else if (passed_pointer
4282 && FUNCTION_ARG_CALLEE_COPIES (args_so_far
,
4283 TYPE_MODE (DECL_ARG_TYPE (parm
)),
4284 DECL_ARG_TYPE (parm
),
4286 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm
)))
4289 tree type
= DECL_ARG_TYPE (parm
);
4291 /* This sequence may involve a library call perhaps clobbering
4292 registers that haven't been copied to pseudos yet. */
4294 push_to_sequence (conversion_insns
);
4296 if (TYPE_SIZE (type
) == 0
4297 || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
4298 /* This is a variable sized object. */
4299 copy
= gen_rtx_MEM (BLKmode
,
4300 allocate_dynamic_stack_space
4301 (expr_size (parm
), NULL_RTX
,
4302 TYPE_ALIGN (type
)));
4304 copy
= assign_stack_temp (TYPE_MODE (type
),
4305 int_size_in_bytes (type
), 1);
4306 MEM_IN_STRUCT_P (copy
) = AGGREGATE_TYPE_P (type
);
4307 RTX_UNCHANGING_P (copy
) = TREE_READONLY (parm
);
4309 store_expr (parm
, copy
, 0);
4310 emit_move_insn (parmreg
, XEXP (copy
, 0));
4311 if (flag_check_memory_usage
)
4312 emit_library_call (chkr_set_right_libfunc
, 1, VOIDmode
, 3,
4313 XEXP (copy
, 0), ptr_mode
,
4314 GEN_INT (int_size_in_bytes (type
)),
4315 TYPE_MODE (sizetype
),
4316 GEN_INT (MEMORY_USE_RW
),
4317 TYPE_MODE (integer_type_node
));
4318 conversion_insns
= get_insns ();
4322 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4324 /* In any case, record the parm's desired stack location
4325 in case we later discover it must live in the stack.
4327 If it is a COMPLEX value, store the stack location for both
4330 if (GET_CODE (parmreg
) == CONCAT
)
4331 regno
= MAX (REGNO (XEXP (parmreg
, 0)), REGNO (XEXP (parmreg
, 1)));
4333 regno
= REGNO (parmreg
);
4335 if (regno
>= max_parm_reg
)
4338 int old_max_parm_reg
= max_parm_reg
;
4340 /* It's slow to expand this one register at a time,
4341 but it's also rare and we need max_parm_reg to be
4342 precisely correct. */
4343 max_parm_reg
= regno
+ 1;
4344 new = (rtx
*) savealloc (max_parm_reg
* sizeof (rtx
));
4345 bcopy ((char *) parm_reg_stack_loc
, (char *) new,
4346 old_max_parm_reg
* sizeof (rtx
));
4347 bzero ((char *) (new + old_max_parm_reg
),
4348 (max_parm_reg
- old_max_parm_reg
) * sizeof (rtx
));
4349 parm_reg_stack_loc
= new;
4352 if (GET_CODE (parmreg
) == CONCAT
)
4354 enum machine_mode submode
= GET_MODE (XEXP (parmreg
, 0));
4356 regnor
= REGNO (gen_realpart (submode
, parmreg
));
4357 regnoi
= REGNO (gen_imagpart (submode
, parmreg
));
4359 if (stack_parm
!= 0)
4361 parm_reg_stack_loc
[regnor
]
4362 = gen_realpart (submode
, stack_parm
);
4363 parm_reg_stack_loc
[regnoi
]
4364 = gen_imagpart (submode
, stack_parm
);
4368 parm_reg_stack_loc
[regnor
] = 0;
4369 parm_reg_stack_loc
[regnoi
] = 0;
4373 parm_reg_stack_loc
[REGNO (parmreg
)] = stack_parm
;
4375 /* Mark the register as eliminable if we did no conversion
4376 and it was copied from memory at a fixed offset,
4377 and the arg pointer was not copied to a pseudo-reg.
4378 If the arg pointer is a pseudo reg or the offset formed
4379 an invalid address, such memory-equivalences
4380 as we make here would screw up life analysis for it. */
4381 if (nominal_mode
== passed_mode
4384 && GET_CODE (stack_parm
) == MEM
4385 && stack_offset
.var
== 0
4386 && reg_mentioned_p (virtual_incoming_args_rtx
,
4387 XEXP (stack_parm
, 0)))
4389 rtx linsn
= get_last_insn ();
4392 /* Mark complex types separately. */
4393 if (GET_CODE (parmreg
) == CONCAT
)
4394 /* Scan backwards for the set of the real and
4396 for (sinsn
= linsn
; sinsn
!= 0;
4397 sinsn
= prev_nonnote_insn (sinsn
))
4399 set
= single_set (sinsn
);
4401 && SET_DEST (set
) == regno_reg_rtx
[regnoi
])
4403 = gen_rtx_EXPR_LIST (REG_EQUIV
,
4404 parm_reg_stack_loc
[regnoi
],
4407 && SET_DEST (set
) == regno_reg_rtx
[regnor
])
4409 = gen_rtx_EXPR_LIST (REG_EQUIV
,
4410 parm_reg_stack_loc
[regnor
],
4413 else if ((set
= single_set (linsn
)) != 0
4414 && SET_DEST (set
) == parmreg
)
4416 = gen_rtx_EXPR_LIST (REG_EQUIV
,
4417 stack_parm
, REG_NOTES (linsn
));
4420 /* For pointer data type, suggest pointer register. */
4421 if (POINTER_TYPE_P (TREE_TYPE (parm
)))
4422 mark_reg_pointer (parmreg
,
4423 (TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
)))
4428 /* Value must be stored in the stack slot STACK_PARM
4429 during function execution. */
4431 if (promoted_mode
!= nominal_mode
)
4433 /* Conversion is required. */
4434 rtx tempreg
= gen_reg_rtx (GET_MODE (entry_parm
));
4436 emit_move_insn (tempreg
, validize_mem (entry_parm
));
4438 push_to_sequence (conversion_insns
);
4439 entry_parm
= convert_to_mode (nominal_mode
, tempreg
,
4440 TREE_UNSIGNED (TREE_TYPE (parm
)));
4443 /* ??? This may need a big-endian conversion on sparc64. */
4444 stack_parm
= change_address (stack_parm
, nominal_mode
,
4447 conversion_insns
= get_insns ();
4452 if (entry_parm
!= stack_parm
)
4454 if (stack_parm
== 0)
4457 = assign_stack_local (GET_MODE (entry_parm
),
4458 GET_MODE_SIZE (GET_MODE (entry_parm
)), 0);
4459 /* If this is a memory ref that contains aggregate components,
4460 mark it as such for cse and loop optimize. */
4461 MEM_IN_STRUCT_P (stack_parm
) = aggregate
;
4464 if (promoted_mode
!= nominal_mode
)
4466 push_to_sequence (conversion_insns
);
4467 emit_move_insn (validize_mem (stack_parm
),
4468 validize_mem (entry_parm
));
4469 conversion_insns
= get_insns ();
4473 emit_move_insn (validize_mem (stack_parm
),
4474 validize_mem (entry_parm
));
4476 if (flag_check_memory_usage
)
4478 push_to_sequence (conversion_insns
);
4479 emit_library_call (chkr_set_right_libfunc
, 1, VOIDmode
, 3,
4480 XEXP (stack_parm
, 0), ptr_mode
,
4481 GEN_INT (GET_MODE_SIZE (GET_MODE
4483 TYPE_MODE (sizetype
),
4484 GEN_INT (MEMORY_USE_RW
),
4485 TYPE_MODE (integer_type_node
));
4487 conversion_insns
= get_insns ();
4490 DECL_RTL (parm
) = stack_parm
;
4493 /* If this "parameter" was the place where we are receiving the
4494 function's incoming structure pointer, set up the result. */
4495 if (parm
== function_result_decl
)
4497 tree result
= DECL_RESULT (fndecl
);
4498 tree restype
= TREE_TYPE (result
);
4501 = gen_rtx_MEM (DECL_MODE (result
), DECL_RTL (parm
));
4503 MEM_IN_STRUCT_P (DECL_RTL (result
)) = AGGREGATE_TYPE_P (restype
);
4506 if (TREE_THIS_VOLATILE (parm
))
4507 MEM_VOLATILE_P (DECL_RTL (parm
)) = 1;
4508 if (TREE_READONLY (parm
))
4509 RTX_UNCHANGING_P (DECL_RTL (parm
)) = 1;
4512 /* Output all parameter conversion instructions (possibly including calls)
4513 now that all parameters have been copied out of hard registers. */
4514 emit_insns (conversion_insns
);
4516 last_parm_insn
= get_last_insn ();
4518 current_function_args_size
= stack_args_size
.constant
;
4520 /* Adjust function incoming argument size for alignment and
4523 #ifdef REG_PARM_STACK_SPACE
4524 #ifndef MAYBE_REG_PARM_STACK_SPACE
4525 current_function_args_size
= MAX (current_function_args_size
,
4526 REG_PARM_STACK_SPACE (fndecl
));
4530 #ifdef STACK_BOUNDARY
4531 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
4533 current_function_args_size
4534 = ((current_function_args_size
+ STACK_BYTES
- 1)
4535 / STACK_BYTES
) * STACK_BYTES
;
4538 #ifdef ARGS_GROW_DOWNWARD
4539 current_function_arg_offset_rtx
4540 = (stack_args_size
.var
== 0 ? GEN_INT (-stack_args_size
.constant
)
4541 : expand_expr (size_binop (MINUS_EXPR
, stack_args_size
.var
,
4542 size_int (-stack_args_size
.constant
)),
4543 NULL_RTX
, VOIDmode
, EXPAND_MEMORY_USE_BAD
));
4545 current_function_arg_offset_rtx
= ARGS_SIZE_RTX (stack_args_size
);
4548 /* See how many bytes, if any, of its args a function should try to pop
4551 current_function_pops_args
= RETURN_POPS_ARGS (fndecl
, TREE_TYPE (fndecl
),
4552 current_function_args_size
);
4554 /* For stdarg.h function, save info about
4555 regs and stack space used by the named args. */
4558 current_function_args_info
= args_so_far
;
4560 /* Set the rtx used for the function return value. Put this in its
4561 own variable so any optimizers that need this information don't have
4562 to include tree.h. Do this here so it gets done when an inlined
4563 function gets output. */
4565 current_function_return_rtx
= DECL_RTL (DECL_RESULT (fndecl
));
4568 /* Indicate whether REGNO is an incoming argument to the current function
4569 that was promoted to a wider mode. If so, return the RTX for the
4570 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
4571 that REGNO is promoted from and whether the promotion was signed or
4574 #ifdef PROMOTE_FUNCTION_ARGS
4577 promoted_input_arg (regno
, pmode
, punsignedp
)
4579 enum machine_mode
*pmode
;
4584 for (arg
= DECL_ARGUMENTS (current_function_decl
); arg
;
4585 arg
= TREE_CHAIN (arg
))
4586 if (GET_CODE (DECL_INCOMING_RTL (arg
)) == REG
4587 && REGNO (DECL_INCOMING_RTL (arg
)) == regno
4588 && TYPE_MODE (DECL_ARG_TYPE (arg
)) == TYPE_MODE (TREE_TYPE (arg
)))
4590 enum machine_mode mode
= TYPE_MODE (TREE_TYPE (arg
));
4591 int unsignedp
= TREE_UNSIGNED (TREE_TYPE (arg
));
4593 mode
= promote_mode (TREE_TYPE (arg
), mode
, &unsignedp
, 1);
4594 if (mode
== GET_MODE (DECL_INCOMING_RTL (arg
))
4595 && mode
!= DECL_MODE (arg
))
4597 *pmode
= DECL_MODE (arg
);
4598 *punsignedp
= unsignedp
;
4599 return DECL_INCOMING_RTL (arg
);
4608 /* Compute the size and offset from the start of the stacked arguments for a
4609 parm passed in mode PASSED_MODE and with type TYPE.
4611 INITIAL_OFFSET_PTR points to the current offset into the stacked
4614 The starting offset and size for this parm are returned in *OFFSET_PTR
4615 and *ARG_SIZE_PTR, respectively.
4617 IN_REGS is non-zero if the argument will be passed in registers. It will
4618 never be set if REG_PARM_STACK_SPACE is not defined.
4620 FNDECL is the function in which the argument was defined.
4622 There are two types of rounding that are done. The first, controlled by
4623 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
4624 list to be aligned to the specific boundary (in bits). This rounding
4625 affects the initial and starting offsets, but not the argument size.
4627 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
4628 optionally rounds the size of the parm to PARM_BOUNDARY. The
4629 initial offset is not affected by this rounding, while the size always
4630 is and the starting offset may be. */
4632 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
4633 initial_offset_ptr is positive because locate_and_pad_parm's
4634 callers pass in the total size of args so far as
4635 initial_offset_ptr. arg_size_ptr is always positive.*/
4638 locate_and_pad_parm (passed_mode
, type
, in_regs
, fndecl
,
4639 initial_offset_ptr
, offset_ptr
, arg_size_ptr
)
4640 enum machine_mode passed_mode
;
4644 struct args_size
*initial_offset_ptr
;
4645 struct args_size
*offset_ptr
;
4646 struct args_size
*arg_size_ptr
;
4649 = type
? size_in_bytes (type
) : size_int (GET_MODE_SIZE (passed_mode
));
4650 enum direction where_pad
= FUNCTION_ARG_PADDING (passed_mode
, type
);
4651 int boundary
= FUNCTION_ARG_BOUNDARY (passed_mode
, type
);
4653 #ifdef REG_PARM_STACK_SPACE
4654 /* If we have found a stack parm before we reach the end of the
4655 area reserved for registers, skip that area. */
4658 int reg_parm_stack_space
= 0;
4660 #ifdef MAYBE_REG_PARM_STACK_SPACE
4661 reg_parm_stack_space
= MAYBE_REG_PARM_STACK_SPACE
;
4663 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
4665 if (reg_parm_stack_space
> 0)
4667 if (initial_offset_ptr
->var
)
4669 initial_offset_ptr
->var
4670 = size_binop (MAX_EXPR
, ARGS_SIZE_TREE (*initial_offset_ptr
),
4671 size_int (reg_parm_stack_space
));
4672 initial_offset_ptr
->constant
= 0;
4674 else if (initial_offset_ptr
->constant
< reg_parm_stack_space
)
4675 initial_offset_ptr
->constant
= reg_parm_stack_space
;
4678 #endif /* REG_PARM_STACK_SPACE */
4680 arg_size_ptr
->var
= 0;
4681 arg_size_ptr
->constant
= 0;
4683 #ifdef ARGS_GROW_DOWNWARD
4684 if (initial_offset_ptr
->var
)
4686 offset_ptr
->constant
= 0;
4687 offset_ptr
->var
= size_binop (MINUS_EXPR
, integer_zero_node
,
4688 initial_offset_ptr
->var
);
4692 offset_ptr
->constant
= - initial_offset_ptr
->constant
;
4693 offset_ptr
->var
= 0;
4695 if (where_pad
!= none
4696 && (TREE_CODE (sizetree
) != INTEGER_CST
4697 || ((TREE_INT_CST_LOW (sizetree
) * BITS_PER_UNIT
) % PARM_BOUNDARY
)))
4698 sizetree
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
4699 SUB_PARM_SIZE (*offset_ptr
, sizetree
);
4700 if (where_pad
!= downward
)
4701 pad_to_arg_alignment (offset_ptr
, boundary
);
4702 if (initial_offset_ptr
->var
)
4704 arg_size_ptr
->var
= size_binop (MINUS_EXPR
,
4705 size_binop (MINUS_EXPR
,
4707 initial_offset_ptr
->var
),
4712 arg_size_ptr
->constant
= (- initial_offset_ptr
->constant
4713 - offset_ptr
->constant
);
4715 #else /* !ARGS_GROW_DOWNWARD */
4716 pad_to_arg_alignment (initial_offset_ptr
, boundary
);
4717 *offset_ptr
= *initial_offset_ptr
;
4719 #ifdef PUSH_ROUNDING
4720 if (passed_mode
!= BLKmode
)
4721 sizetree
= size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree
)));
4724 /* Pad_below needs the pre-rounded size to know how much to pad below
4725 so this must be done before rounding up. */
4726 if (where_pad
== downward
4727 /* However, BLKmode args passed in regs have their padding done elsewhere.
4728 The stack slot must be able to hold the entire register. */
4729 && !(in_regs
&& passed_mode
== BLKmode
))
4730 pad_below (offset_ptr
, passed_mode
, sizetree
);
4732 if (where_pad
!= none
4733 && (TREE_CODE (sizetree
) != INTEGER_CST
4734 || ((TREE_INT_CST_LOW (sizetree
) * BITS_PER_UNIT
) % PARM_BOUNDARY
)))
4735 sizetree
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
4737 ADD_PARM_SIZE (*arg_size_ptr
, sizetree
);
4738 #endif /* ARGS_GROW_DOWNWARD */
4741 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
4742 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
4745 pad_to_arg_alignment (offset_ptr
, boundary
)
4746 struct args_size
*offset_ptr
;
4749 int boundary_in_bytes
= boundary
/ BITS_PER_UNIT
;
4751 if (boundary
> BITS_PER_UNIT
)
4753 if (offset_ptr
->var
)
4756 #ifdef ARGS_GROW_DOWNWARD
4761 (ARGS_SIZE_TREE (*offset_ptr
),
4762 boundary
/ BITS_PER_UNIT
);
4763 offset_ptr
->constant
= 0; /*?*/
4766 offset_ptr
->constant
=
4767 #ifdef ARGS_GROW_DOWNWARD
4768 FLOOR_ROUND (offset_ptr
->constant
, boundary_in_bytes
);
4770 CEIL_ROUND (offset_ptr
->constant
, boundary_in_bytes
);
4775 #ifndef ARGS_GROW_DOWNWARD
4777 pad_below (offset_ptr
, passed_mode
, sizetree
)
4778 struct args_size
*offset_ptr
;
4779 enum machine_mode passed_mode
;
4782 if (passed_mode
!= BLKmode
)
4784 if (GET_MODE_BITSIZE (passed_mode
) % PARM_BOUNDARY
)
4785 offset_ptr
->constant
4786 += (((GET_MODE_BITSIZE (passed_mode
) + PARM_BOUNDARY
- 1)
4787 / PARM_BOUNDARY
* PARM_BOUNDARY
/ BITS_PER_UNIT
)
4788 - GET_MODE_SIZE (passed_mode
));
4792 if (TREE_CODE (sizetree
) != INTEGER_CST
4793 || (TREE_INT_CST_LOW (sizetree
) * BITS_PER_UNIT
) % PARM_BOUNDARY
)
4795 /* Round the size up to multiple of PARM_BOUNDARY bits. */
4796 tree s2
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
4798 ADD_PARM_SIZE (*offset_ptr
, s2
);
4799 SUB_PARM_SIZE (*offset_ptr
, sizetree
);
4805 #ifdef ARGS_GROW_DOWNWARD
4807 round_down (value
, divisor
)
4811 return size_binop (MULT_EXPR
,
4812 size_binop (FLOOR_DIV_EXPR
, value
, size_int (divisor
)),
4813 size_int (divisor
));
4817 /* Walk the tree of blocks describing the binding levels within a function
4818 and warn about uninitialized variables.
4819 This is done after calling flow_analysis and before global_alloc
4820 clobbers the pseudo-regs to hard regs. */
4823 uninitialized_vars_warning (block
)
4826 register tree decl
, sub
;
4827 for (decl
= BLOCK_VARS (block
); decl
; decl
= TREE_CHAIN (decl
))
4829 if (TREE_CODE (decl
) == VAR_DECL
4830 /* These warnings are unreliable for and aggregates
4831 because assigning the fields one by one can fail to convince
4832 flow.c that the entire aggregate was initialized.
4833 Unions are troublesome because members may be shorter. */
4834 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl
))
4835 && DECL_RTL (decl
) != 0
4836 && GET_CODE (DECL_RTL (decl
)) == REG
4837 && regno_uninitialized (REGNO (DECL_RTL (decl
))))
4838 warning_with_decl (decl
,
4839 "`%s' might be used uninitialized in this function");
4840 if (TREE_CODE (decl
) == VAR_DECL
4841 && DECL_RTL (decl
) != 0
4842 && GET_CODE (DECL_RTL (decl
)) == REG
4843 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl
))))
4844 warning_with_decl (decl
,
4845 "variable `%s' might be clobbered by `longjmp' or `vfork'");
4847 for (sub
= BLOCK_SUBBLOCKS (block
); sub
; sub
= TREE_CHAIN (sub
))
4848 uninitialized_vars_warning (sub
);
4851 /* Do the appropriate part of uninitialized_vars_warning
4852 but for arguments instead of local variables. */
4855 setjmp_args_warning ()
4858 for (decl
= DECL_ARGUMENTS (current_function_decl
);
4859 decl
; decl
= TREE_CHAIN (decl
))
4860 if (DECL_RTL (decl
) != 0
4861 && GET_CODE (DECL_RTL (decl
)) == REG
4862 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl
))))
4863 warning_with_decl (decl
, "argument `%s' might be clobbered by `longjmp' or `vfork'");
4866 /* If this function call setjmp, put all vars into the stack
4867 unless they were declared `register'. */
4870 setjmp_protect (block
)
4873 register tree decl
, sub
;
4874 for (decl
= BLOCK_VARS (block
); decl
; decl
= TREE_CHAIN (decl
))
4875 if ((TREE_CODE (decl
) == VAR_DECL
4876 || TREE_CODE (decl
) == PARM_DECL
)
4877 && DECL_RTL (decl
) != 0
4878 && (GET_CODE (DECL_RTL (decl
)) == REG
4879 || (GET_CODE (DECL_RTL (decl
)) == MEM
4880 && GET_CODE (XEXP (DECL_RTL (decl
), 0)) == ADDRESSOF
))
4881 /* If this variable came from an inline function, it must be
4882 that its life doesn't overlap the setjmp. If there was a
4883 setjmp in the function, it would already be in memory. We
4884 must exclude such variable because their DECL_RTL might be
4885 set to strange things such as virtual_stack_vars_rtx. */
4886 && ! DECL_FROM_INLINE (decl
)
4888 #ifdef NON_SAVING_SETJMP
4889 /* If longjmp doesn't restore the registers,
4890 don't put anything in them. */
4894 ! DECL_REGISTER (decl
)))
4895 put_var_into_stack (decl
);
4896 for (sub
= BLOCK_SUBBLOCKS (block
); sub
; sub
= TREE_CHAIN (sub
))
4897 setjmp_protect (sub
);
4900 /* Like the previous function, but for args instead of local variables. */
4903 setjmp_protect_args ()
4906 for (decl
= DECL_ARGUMENTS (current_function_decl
);
4907 decl
; decl
= TREE_CHAIN (decl
))
4908 if ((TREE_CODE (decl
) == VAR_DECL
4909 || TREE_CODE (decl
) == PARM_DECL
)
4910 && DECL_RTL (decl
) != 0
4911 && (GET_CODE (DECL_RTL (decl
)) == REG
4912 || (GET_CODE (DECL_RTL (decl
)) == MEM
4913 && GET_CODE (XEXP (DECL_RTL (decl
), 0)) == ADDRESSOF
))
4915 /* If longjmp doesn't restore the registers,
4916 don't put anything in them. */
4917 #ifdef NON_SAVING_SETJMP
4921 ! DECL_REGISTER (decl
)))
4922 put_var_into_stack (decl
);
4925 /* Return the context-pointer register corresponding to DECL,
4926 or 0 if it does not need one. */
4929 lookup_static_chain (decl
)
4932 tree context
= decl_function_context (decl
);
4936 || (TREE_CODE (decl
) == FUNCTION_DECL
&& DECL_NO_STATIC_CHAIN (decl
)))
4939 /* We treat inline_function_decl as an alias for the current function
4940 because that is the inline function whose vars, types, etc.
4941 are being merged into the current function.
4942 See expand_inline_function. */
4943 if (context
== current_function_decl
|| context
== inline_function_decl
)
4944 return virtual_stack_vars_rtx
;
4946 for (link
= context_display
; link
; link
= TREE_CHAIN (link
))
4947 if (TREE_PURPOSE (link
) == context
)
4948 return RTL_EXPR_RTL (TREE_VALUE (link
));
4953 /* Convert a stack slot address ADDR for variable VAR
4954 (from a containing function)
4955 into an address valid in this function (using a static chain). */
4958 fix_lexical_addr (addr
, var
)
4963 HOST_WIDE_INT displacement
;
4964 tree context
= decl_function_context (var
);
4965 struct function
*fp
;
4968 /* If this is the present function, we need not do anything. */
4969 if (context
== current_function_decl
|| context
== inline_function_decl
)
4972 for (fp
= outer_function_chain
; fp
; fp
= fp
->next
)
4973 if (fp
->decl
== context
)
4979 if (GET_CODE (addr
) == ADDRESSOF
&& GET_CODE (XEXP (addr
, 0)) == MEM
)
4980 addr
= XEXP (XEXP (addr
, 0), 0);
4982 /* Decode given address as base reg plus displacement. */
4983 if (GET_CODE (addr
) == REG
)
4984 basereg
= addr
, displacement
= 0;
4985 else if (GET_CODE (addr
) == PLUS
&& GET_CODE (XEXP (addr
, 1)) == CONST_INT
)
4986 basereg
= XEXP (addr
, 0), displacement
= INTVAL (XEXP (addr
, 1));
4990 /* We accept vars reached via the containing function's
4991 incoming arg pointer and via its stack variables pointer. */
4992 if (basereg
== fp
->internal_arg_pointer
)
4994 /* If reached via arg pointer, get the arg pointer value
4995 out of that function's stack frame.
4997 There are two cases: If a separate ap is needed, allocate a
4998 slot in the outer function for it and dereference it that way.
4999 This is correct even if the real ap is actually a pseudo.
5000 Otherwise, just adjust the offset from the frame pointer to
5003 #ifdef NEED_SEPARATE_AP
5006 if (fp
->arg_pointer_save_area
== 0)
5007 fp
->arg_pointer_save_area
5008 = assign_outer_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0, fp
);
5010 addr
= fix_lexical_addr (XEXP (fp
->arg_pointer_save_area
, 0), var
);
5011 addr
= memory_address (Pmode
, addr
);
5013 base
= copy_to_reg (gen_rtx_MEM (Pmode
, addr
));
5015 displacement
+= (FIRST_PARM_OFFSET (context
) - STARTING_FRAME_OFFSET
);
5016 base
= lookup_static_chain (var
);
5020 else if (basereg
== virtual_stack_vars_rtx
)
5022 /* This is the same code as lookup_static_chain, duplicated here to
5023 avoid an extra call to decl_function_context. */
5026 for (link
= context_display
; link
; link
= TREE_CHAIN (link
))
5027 if (TREE_PURPOSE (link
) == context
)
5029 base
= RTL_EXPR_RTL (TREE_VALUE (link
));
5037 /* Use same offset, relative to appropriate static chain or argument
5039 return plus_constant (base
, displacement
);
5042 /* Return the address of the trampoline for entering nested fn FUNCTION.
5043 If necessary, allocate a trampoline (in the stack frame)
5044 and emit rtl to initialize its contents (at entry to this function). */
5047 trampoline_address (function
)
5053 struct function
*fp
;
5056 /* Find an existing trampoline and return it. */
5057 for (link
= trampoline_list
; link
; link
= TREE_CHAIN (link
))
5058 if (TREE_PURPOSE (link
) == function
)
5060 round_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link
)), 0));
5062 for (fp
= outer_function_chain
; fp
; fp
= fp
->next
)
5063 for (link
= fp
->trampoline_list
; link
; link
= TREE_CHAIN (link
))
5064 if (TREE_PURPOSE (link
) == function
)
5066 tramp
= fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link
)), 0),
5068 return round_trampoline_addr (tramp
);
5071 /* None exists; we must make one. */
5073 /* Find the `struct function' for the function containing FUNCTION. */
5075 fn_context
= decl_function_context (function
);
5076 if (fn_context
!= current_function_decl
5077 && fn_context
!= inline_function_decl
)
5078 for (fp
= outer_function_chain
; fp
; fp
= fp
->next
)
5079 if (fp
->decl
== fn_context
)
5082 /* Allocate run-time space for this trampoline
5083 (usually in the defining function's stack frame). */
5084 #ifdef ALLOCATE_TRAMPOLINE
5085 tramp
= ALLOCATE_TRAMPOLINE (fp
);
5087 /* If rounding needed, allocate extra space
5088 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5089 #ifdef TRAMPOLINE_ALIGNMENT
5090 #define TRAMPOLINE_REAL_SIZE \
5091 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5093 #define TRAMPOLINE_REAL_SIZE (TRAMPOLINE_SIZE)
5096 tramp
= assign_outer_stack_local (BLKmode
, TRAMPOLINE_REAL_SIZE
, 0, fp
);
5098 tramp
= assign_stack_local (BLKmode
, TRAMPOLINE_REAL_SIZE
, 0);
5101 /* Record the trampoline for reuse and note it for later initialization
5102 by expand_function_end. */
5105 push_obstacks (fp
->function_maybepermanent_obstack
,
5106 fp
->function_maybepermanent_obstack
);
5107 rtlexp
= make_node (RTL_EXPR
);
5108 RTL_EXPR_RTL (rtlexp
) = tramp
;
5109 fp
->trampoline_list
= tree_cons (function
, rtlexp
, fp
->trampoline_list
);
5114 /* Make the RTL_EXPR node temporary, not momentary, so that the
5115 trampoline_list doesn't become garbage. */
5116 int momentary
= suspend_momentary ();
5117 rtlexp
= make_node (RTL_EXPR
);
5118 resume_momentary (momentary
);
5120 RTL_EXPR_RTL (rtlexp
) = tramp
;
5121 trampoline_list
= tree_cons (function
, rtlexp
, trampoline_list
);
5124 tramp
= fix_lexical_addr (XEXP (tramp
, 0), function
);
5125 return round_trampoline_addr (tramp
);
5128 /* Given a trampoline address,
5129 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5132 round_trampoline_addr (tramp
)
5135 #ifdef TRAMPOLINE_ALIGNMENT
5136 /* Round address up to desired boundary. */
5137 rtx temp
= gen_reg_rtx (Pmode
);
5138 temp
= expand_binop (Pmode
, add_optab
, tramp
,
5139 GEN_INT (TRAMPOLINE_ALIGNMENT
/ BITS_PER_UNIT
- 1),
5140 temp
, 0, OPTAB_LIB_WIDEN
);
5141 tramp
= expand_binop (Pmode
, and_optab
, temp
,
5142 GEN_INT (- TRAMPOLINE_ALIGNMENT
/ BITS_PER_UNIT
),
5143 temp
, 0, OPTAB_LIB_WIDEN
);
5148 /* The functions identify_blocks and reorder_blocks provide a way to
5149 reorder the tree of BLOCK nodes, for optimizers that reshuffle or
5150 duplicate portions of the RTL code. Call identify_blocks before
5151 changing the RTL, and call reorder_blocks after. */
5153 /* Put all this function's BLOCK nodes including those that are chained
5154 onto the first block into a vector, and return it.
5155 Also store in each NOTE for the beginning or end of a block
5156 the index of that block in the vector.
5157 The arguments are BLOCK, the chain of top-level blocks of the function,
5158 and INSNS, the insn chain of the function. */
5161 identify_blocks (block
, insns
)
5169 int next_block_number
= 1;
5170 int current_block_number
= 1;
5176 n_blocks
= all_blocks (block
, 0);
5177 block_vector
= (tree
*) xmalloc (n_blocks
* sizeof (tree
));
5178 block_stack
= (int *) alloca (n_blocks
* sizeof (int));
5180 all_blocks (block
, block_vector
);
5182 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
5183 if (GET_CODE (insn
) == NOTE
)
5185 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_BEG
)
5187 block_stack
[depth
++] = current_block_number
;
5188 current_block_number
= next_block_number
;
5189 NOTE_BLOCK_NUMBER (insn
) = next_block_number
++;
5191 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_END
)
5193 NOTE_BLOCK_NUMBER (insn
) = current_block_number
;
5194 current_block_number
= block_stack
[--depth
];
5198 if (n_blocks
!= next_block_number
)
5201 return block_vector
;
5204 /* Given BLOCK_VECTOR which was returned by identify_blocks,
5205 and a revised instruction chain, rebuild the tree structure
5206 of BLOCK nodes to correspond to the new order of RTL.
5207 The new block tree is inserted below TOP_BLOCK.
5208 Returns the current top-level block. */
5211 reorder_blocks (block_vector
, block
, insns
)
5216 tree current_block
= block
;
5219 if (block_vector
== 0)
5222 /* Prune the old trees away, so that it doesn't get in the way. */
5223 BLOCK_SUBBLOCKS (current_block
) = 0;
5224 BLOCK_CHAIN (current_block
) = 0;
5226 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
5227 if (GET_CODE (insn
) == NOTE
)
5229 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_BEG
)
5231 tree block
= block_vector
[NOTE_BLOCK_NUMBER (insn
)];
5232 /* If we have seen this block before, copy it. */
5233 if (TREE_ASM_WRITTEN (block
))
5234 block
= copy_node (block
);
5235 BLOCK_SUBBLOCKS (block
) = 0;
5236 TREE_ASM_WRITTEN (block
) = 1;
5237 BLOCK_SUPERCONTEXT (block
) = current_block
;
5238 BLOCK_CHAIN (block
) = BLOCK_SUBBLOCKS (current_block
);
5239 BLOCK_SUBBLOCKS (current_block
) = block
;
5240 current_block
= block
;
5241 NOTE_SOURCE_FILE (insn
) = 0;
5243 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_END
)
5245 BLOCK_SUBBLOCKS (current_block
)
5246 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block
));
5247 current_block
= BLOCK_SUPERCONTEXT (current_block
);
5248 NOTE_SOURCE_FILE (insn
) = 0;
5252 BLOCK_SUBBLOCKS (current_block
)
5253 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block
));
5254 return current_block
;
5257 /* Reverse the order of elements in the chain T of blocks,
5258 and return the new head of the chain (old last element). */
5264 register tree prev
= 0, decl
, next
;
5265 for (decl
= t
; decl
; decl
= next
)
5267 next
= BLOCK_CHAIN (decl
);
5268 BLOCK_CHAIN (decl
) = prev
;
5274 /* Count the subblocks of the list starting with BLOCK, and list them
5275 all into the vector VECTOR. Also clear TREE_ASM_WRITTEN in all
5279 all_blocks (block
, vector
)
5287 TREE_ASM_WRITTEN (block
) = 0;
5289 /* Record this block. */
5291 vector
[n_blocks
] = block
;
5295 /* Record the subblocks, and their subblocks... */
5296 n_blocks
+= all_blocks (BLOCK_SUBBLOCKS (block
),
5297 vector
? vector
+ n_blocks
: 0);
5298 block
= BLOCK_CHAIN (block
);
5304 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
5305 and initialize static variables for generating RTL for the statements
5309 init_function_start (subr
, filename
, line
)
5314 init_stmt_for_function ();
5316 cse_not_expected
= ! optimize
;
5318 /* Caller save not needed yet. */
5319 caller_save_needed
= 0;
5321 /* No stack slots have been made yet. */
5322 stack_slot_list
= 0;
5324 /* There is no stack slot for handling nonlocal gotos. */
5325 nonlocal_goto_handler_slot
= 0;
5326 nonlocal_goto_stack_level
= 0;
5328 /* No labels have been declared for nonlocal use. */
5329 nonlocal_labels
= 0;
5331 /* No function calls so far in this function. */
5332 function_call_count
= 0;
5334 /* No parm regs have been allocated.
5335 (This is important for output_inline_function.) */
5336 max_parm_reg
= LAST_VIRTUAL_REGISTER
+ 1;
5338 /* Initialize the RTL mechanism. */
5341 /* Initialize the queue of pending postincrement and postdecrements,
5342 and some other info in expr.c. */
5345 /* We haven't done register allocation yet. */
5348 init_const_rtx_hash_table ();
5350 current_function_name
= (*decl_printable_name
) (subr
, 2);
5352 /* Nonzero if this is a nested function that uses a static chain. */
5354 current_function_needs_context
5355 = (decl_function_context (current_function_decl
) != 0
5356 && ! DECL_NO_STATIC_CHAIN (current_function_decl
));
5358 /* Set if a call to setjmp is seen. */
5359 current_function_calls_setjmp
= 0;
5361 /* Set if a call to longjmp is seen. */
5362 current_function_calls_longjmp
= 0;
5364 current_function_calls_alloca
= 0;
5365 current_function_has_nonlocal_label
= 0;
5366 current_function_has_nonlocal_goto
= 0;
5367 current_function_contains_functions
= 0;
5368 current_function_is_thunk
= 0;
5370 current_function_returns_pcc_struct
= 0;
5371 current_function_returns_struct
= 0;
5372 current_function_epilogue_delay_list
= 0;
5373 current_function_uses_const_pool
= 0;
5374 current_function_uses_pic_offset_table
= 0;
5375 current_function_cannot_inline
= 0;
5377 /* We have not yet needed to make a label to jump to for tail-recursion. */
5378 tail_recursion_label
= 0;
5380 /* We haven't had a need to make a save area for ap yet. */
5382 arg_pointer_save_area
= 0;
5384 /* No stack slots allocated yet. */
5387 /* No SAVE_EXPRs in this function yet. */
5390 /* No RTL_EXPRs in this function yet. */
5393 /* Set up to allocate temporaries. */
5396 /* Within function body, compute a type's size as soon it is laid out. */
5397 immediate_size_expand
++;
5399 /* We haven't made any trampolines for this function yet. */
5400 trampoline_list
= 0;
5402 init_pending_stack_adjust ();
5403 inhibit_defer_pop
= 0;
5405 current_function_outgoing_args_size
= 0;
5407 /* Prevent ever trying to delete the first instruction of a function.
5408 Also tell final how to output a linenum before the function prologue.
5409 Note linenums could be missing, e.g. when compiling a Java .class file. */
5411 emit_line_note (filename
, line
);
5413 /* Make sure first insn is a note even if we don't want linenums.
5414 This makes sure the first insn will never be deleted.
5415 Also, final expects a note to appear there. */
5416 emit_note (NULL_PTR
, NOTE_INSN_DELETED
);
5418 /* Set flags used by final.c. */
5419 if (aggregate_value_p (DECL_RESULT (subr
)))
5421 #ifdef PCC_STATIC_STRUCT_RETURN
5422 current_function_returns_pcc_struct
= 1;
5424 current_function_returns_struct
= 1;
5427 /* Warn if this value is an aggregate type,
5428 regardless of which calling convention we are using for it. */
5429 if (warn_aggregate_return
5430 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr
))))
5431 warning ("function returns an aggregate");
5433 current_function_returns_pointer
5434 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr
)));
5436 /* Indicate that we need to distinguish between the return value of the
5437 present function and the return value of a function being called. */
5438 rtx_equal_function_value_matters
= 1;
5440 /* Indicate that we have not instantiated virtual registers yet. */
5441 virtuals_instantiated
= 0;
5443 /* Indicate we have no need of a frame pointer yet. */
5444 frame_pointer_needed
= 0;
5446 /* By default assume not varargs or stdarg. */
5447 current_function_varargs
= 0;
5448 current_function_stdarg
= 0;
5451 /* Indicate that the current function uses extra args
5452 not explicitly mentioned in the argument list in any fashion. */
5457 current_function_varargs
= 1;
5460 /* Expand a call to __main at the beginning of a possible main function. */
5462 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
5463 #undef HAS_INIT_SECTION
5464 #define HAS_INIT_SECTION
5468 expand_main_function ()
5470 #if !defined (HAS_INIT_SECTION)
5471 emit_library_call (gen_rtx_SYMBOL_REF (Pmode
, NAME__MAIN
), 0,
5473 #endif /* not HAS_INIT_SECTION */
5476 extern struct obstack permanent_obstack
;
5478 /* Start the RTL for a new function, and set variables used for
5480 SUBR is the FUNCTION_DECL node.
5481 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
5482 the function's parameters, which must be run at any return statement. */
5485 expand_function_start (subr
, parms_have_cleanups
)
5487 int parms_have_cleanups
;
5491 rtx last_ptr
= NULL_RTX
;
5493 /* Make sure volatile mem refs aren't considered
5494 valid operands of arithmetic insns. */
5495 init_recog_no_volatile ();
5497 current_function_instrument_entry_exit
5498 = (flag_instrument_function_entry_exit
5499 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr
));
5501 /* If function gets a static chain arg, store it in the stack frame.
5502 Do this first, so it gets the first stack slot offset. */
5503 if (current_function_needs_context
)
5505 last_ptr
= assign_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0);
5507 /* Delay copying static chain if it is not a register to avoid
5508 conflicts with regs used for parameters. */
5509 if (! SMALL_REGISTER_CLASSES
5510 || GET_CODE (static_chain_incoming_rtx
) == REG
)
5511 emit_move_insn (last_ptr
, static_chain_incoming_rtx
);
5514 /* If the parameters of this function need cleaning up, get a label
5515 for the beginning of the code which executes those cleanups. This must
5516 be done before doing anything with return_label. */
5517 if (parms_have_cleanups
)
5518 cleanup_label
= gen_label_rtx ();
5522 /* Make the label for return statements to jump to, if this machine
5523 does not have a one-instruction return and uses an epilogue,
5524 or if it returns a structure, or if it has parm cleanups. */
5526 if (cleanup_label
== 0 && HAVE_return
5527 && ! current_function_instrument_entry_exit
5528 && ! current_function_returns_pcc_struct
5529 && ! (current_function_returns_struct
&& ! optimize
))
5532 return_label
= gen_label_rtx ();
5534 return_label
= gen_label_rtx ();
5537 /* Initialize rtx used to return the value. */
5538 /* Do this before assign_parms so that we copy the struct value address
5539 before any library calls that assign parms might generate. */
5541 /* Decide whether to return the value in memory or in a register. */
5542 if (aggregate_value_p (DECL_RESULT (subr
)))
5544 /* Returning something that won't go in a register. */
5545 register rtx value_address
= 0;
5547 #ifdef PCC_STATIC_STRUCT_RETURN
5548 if (current_function_returns_pcc_struct
)
5550 int size
= int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr
)));
5551 value_address
= assemble_static_space (size
);
5556 /* Expect to be passed the address of a place to store the value.
5557 If it is passed as an argument, assign_parms will take care of
5559 if (struct_value_incoming_rtx
)
5561 value_address
= gen_reg_rtx (Pmode
);
5562 emit_move_insn (value_address
, struct_value_incoming_rtx
);
5567 DECL_RTL (DECL_RESULT (subr
))
5568 = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr
)), value_address
);
5569 MEM_IN_STRUCT_P (DECL_RTL (DECL_RESULT (subr
)))
5570 = AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr
)));
5573 else if (DECL_MODE (DECL_RESULT (subr
)) == VOIDmode
)
5574 /* If return mode is void, this decl rtl should not be used. */
5575 DECL_RTL (DECL_RESULT (subr
)) = 0;
5576 else if (parms_have_cleanups
|| current_function_instrument_entry_exit
)
5578 /* If function will end with cleanup code for parms,
5579 compute the return values into a pseudo reg,
5580 which we will copy into the true return register
5581 after the cleanups are done. */
5583 enum machine_mode mode
= DECL_MODE (DECL_RESULT (subr
));
5585 #ifdef PROMOTE_FUNCTION_RETURN
5586 tree type
= TREE_TYPE (DECL_RESULT (subr
));
5587 int unsignedp
= TREE_UNSIGNED (type
);
5589 mode
= promote_mode (type
, mode
, &unsignedp
, 1);
5592 DECL_RTL (DECL_RESULT (subr
)) = gen_reg_rtx (mode
);
5595 /* Scalar, returned in a register. */
5597 #ifdef FUNCTION_OUTGOING_VALUE
5598 DECL_RTL (DECL_RESULT (subr
))
5599 = FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (subr
)), subr
);
5601 DECL_RTL (DECL_RESULT (subr
))
5602 = FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (subr
)), subr
);
5605 /* Mark this reg as the function's return value. */
5606 if (GET_CODE (DECL_RTL (DECL_RESULT (subr
))) == REG
)
5608 REG_FUNCTION_VALUE_P (DECL_RTL (DECL_RESULT (subr
))) = 1;
5609 /* Needed because we may need to move this to memory
5610 in case it's a named return value whose address is taken. */
5611 DECL_REGISTER (DECL_RESULT (subr
)) = 1;
5615 /* Initialize rtx for parameters and local variables.
5616 In some cases this requires emitting insns. */
5618 assign_parms (subr
, 0);
5620 /* Copy the static chain now if it wasn't a register. The delay is to
5621 avoid conflicts with the parameter passing registers. */
5623 if (SMALL_REGISTER_CLASSES
&& current_function_needs_context
)
5624 if (GET_CODE (static_chain_incoming_rtx
) != REG
)
5625 emit_move_insn (last_ptr
, static_chain_incoming_rtx
);
5627 /* The following was moved from init_function_start.
5628 The move is supposed to make sdb output more accurate. */
5629 /* Indicate the beginning of the function body,
5630 as opposed to parm setup. */
5631 emit_note (NULL_PTR
, NOTE_INSN_FUNCTION_BEG
);
5633 /* If doing stupid allocation, mark parms as born here. */
5635 if (GET_CODE (get_last_insn ()) != NOTE
)
5636 emit_note (NULL_PTR
, NOTE_INSN_DELETED
);
5637 parm_birth_insn
= get_last_insn ();
5641 for (i
= LAST_VIRTUAL_REGISTER
+ 1; i
< max_parm_reg
; i
++)
5642 use_variable (regno_reg_rtx
[i
]);
5644 if (current_function_internal_arg_pointer
!= virtual_incoming_args_rtx
)
5645 use_variable (current_function_internal_arg_pointer
);
5648 context_display
= 0;
5649 if (current_function_needs_context
)
5651 /* Fetch static chain values for containing functions. */
5652 tem
= decl_function_context (current_function_decl
);
5653 /* If not doing stupid register allocation copy the static chain
5654 pointer into a pseudo. If we have small register classes, copy
5655 the value from memory if static_chain_incoming_rtx is a REG. If
5656 we do stupid register allocation, we use the stack address
5658 if (tem
&& ! obey_regdecls
)
5660 /* If the static chain originally came in a register, put it back
5661 there, then move it out in the next insn. The reason for
5662 this peculiar code is to satisfy function integration. */
5663 if (SMALL_REGISTER_CLASSES
5664 && GET_CODE (static_chain_incoming_rtx
) == REG
)
5665 emit_move_insn (static_chain_incoming_rtx
, last_ptr
);
5666 last_ptr
= copy_to_reg (static_chain_incoming_rtx
);
5671 tree rtlexp
= make_node (RTL_EXPR
);
5673 RTL_EXPR_RTL (rtlexp
) = last_ptr
;
5674 context_display
= tree_cons (tem
, rtlexp
, context_display
);
5675 tem
= decl_function_context (tem
);
5678 /* Chain thru stack frames, assuming pointer to next lexical frame
5679 is found at the place we always store it. */
5680 #ifdef FRAME_GROWS_DOWNWARD
5681 last_ptr
= plus_constant (last_ptr
, - GET_MODE_SIZE (Pmode
));
5683 last_ptr
= copy_to_reg (gen_rtx_MEM (Pmode
,
5684 memory_address (Pmode
, last_ptr
)));
5686 /* If we are not optimizing, ensure that we know that this
5687 piece of context is live over the entire function. */
5689 save_expr_regs
= gen_rtx_EXPR_LIST (VOIDmode
, last_ptr
,
5694 if (current_function_instrument_entry_exit
)
5696 rtx fun
= DECL_RTL (current_function_decl
);
5697 if (GET_CODE (fun
) == MEM
)
5698 fun
= XEXP (fun
, 0);
5701 emit_library_call (profile_function_entry_libfunc
, 0, VOIDmode
, 2,
5703 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS
,
5705 hard_frame_pointer_rtx
),
5709 /* After the display initializations is where the tail-recursion label
5710 should go, if we end up needing one. Ensure we have a NOTE here
5711 since some things (like trampolines) get placed before this. */
5712 tail_recursion_reentry
= emit_note (NULL_PTR
, NOTE_INSN_DELETED
);
5714 /* Evaluate now the sizes of any types declared among the arguments. */
5715 for (tem
= nreverse (get_pending_sizes ()); tem
; tem
= TREE_CHAIN (tem
))
5717 expand_expr (TREE_VALUE (tem
), const0_rtx
, VOIDmode
,
5718 EXPAND_MEMORY_USE_BAD
);
5719 /* Flush the queue in case this parameter declaration has
5724 /* Make sure there is a line number after the function entry setup code. */
5725 force_next_line_note ();
5728 /* Generate RTL for the end of the current function.
5729 FILENAME and LINE are the current position in the source file.
5731 It is up to language-specific callers to do cleanups for parameters--
5732 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
5735 expand_function_end (filename
, line
, end_bindings
)
5743 #ifdef TRAMPOLINE_TEMPLATE
5744 static rtx initial_trampoline
;
5747 #ifdef NON_SAVING_SETJMP
5748 /* Don't put any variables in registers if we call setjmp
5749 on a machine that fails to restore the registers. */
5750 if (NON_SAVING_SETJMP
&& current_function_calls_setjmp
)
5752 if (DECL_INITIAL (current_function_decl
) != error_mark_node
)
5753 setjmp_protect (DECL_INITIAL (current_function_decl
));
5755 setjmp_protect_args ();
5759 /* Save the argument pointer if a save area was made for it. */
5760 if (arg_pointer_save_area
)
5762 rtx x
= gen_move_insn (arg_pointer_save_area
, virtual_incoming_args_rtx
);
5763 emit_insn_before (x
, tail_recursion_reentry
);
5766 /* Initialize any trampolines required by this function. */
5767 for (link
= trampoline_list
; link
; link
= TREE_CHAIN (link
))
5769 tree function
= TREE_PURPOSE (link
);
5770 rtx context
= lookup_static_chain (function
);
5771 rtx tramp
= RTL_EXPR_RTL (TREE_VALUE (link
));
5772 #ifdef TRAMPOLINE_TEMPLATE
5777 #ifdef TRAMPOLINE_TEMPLATE
5778 /* First make sure this compilation has a template for
5779 initializing trampolines. */
5780 if (initial_trampoline
== 0)
5782 end_temporary_allocation ();
5784 = gen_rtx_MEM (BLKmode
, assemble_trampoline_template ());
5785 resume_temporary_allocation ();
5789 /* Generate insns to initialize the trampoline. */
5791 tramp
= round_trampoline_addr (XEXP (tramp
, 0));
5792 #ifdef TRAMPOLINE_TEMPLATE
5793 blktramp
= change_address (initial_trampoline
, BLKmode
, tramp
);
5794 emit_block_move (blktramp
, initial_trampoline
,
5795 GEN_INT (TRAMPOLINE_SIZE
),
5796 TRAMPOLINE_ALIGNMENT
/ BITS_PER_UNIT
);
5798 INITIALIZE_TRAMPOLINE (tramp
, XEXP (DECL_RTL (function
), 0), context
);
5802 /* Put those insns at entry to the containing function (this one). */
5803 emit_insns_before (seq
, tail_recursion_reentry
);
5806 /* If we are doing stack checking and this function makes calls,
5807 do a stack probe at the start of the function to ensure we have enough
5808 space for another stack frame. */
5809 if (flag_stack_check
&& ! STACK_CHECK_BUILTIN
)
5813 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
5814 if (GET_CODE (insn
) == CALL_INSN
)
5817 probe_stack_range (STACK_CHECK_PROTECT
,
5818 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE
));
5821 emit_insns_before (seq
, tail_recursion_reentry
);
5826 /* Warn about unused parms if extra warnings were specified. */
5827 if (warn_unused
&& extra_warnings
)
5831 for (decl
= DECL_ARGUMENTS (current_function_decl
);
5832 decl
; decl
= TREE_CHAIN (decl
))
5833 if (! TREE_USED (decl
) && TREE_CODE (decl
) == PARM_DECL
5834 && DECL_NAME (decl
) && ! DECL_ARTIFICIAL (decl
))
5835 warning_with_decl (decl
, "unused parameter `%s'");
5838 /* Delete handlers for nonlocal gotos if nothing uses them. */
5839 if (nonlocal_goto_handler_slot
!= 0 && !current_function_has_nonlocal_label
)
5842 /* End any sequences that failed to be closed due to syntax errors. */
5843 while (in_sequence_p ())
5846 /* Outside function body, can't compute type's actual size
5847 until next function's body starts. */
5848 immediate_size_expand
--;
5850 /* If doing stupid register allocation,
5851 mark register parms as dying here. */
5856 for (i
= LAST_VIRTUAL_REGISTER
+ 1; i
< max_parm_reg
; i
++)
5857 use_variable (regno_reg_rtx
[i
]);
5859 /* Likewise for the regs of all the SAVE_EXPRs in the function. */
5861 for (tem
= save_expr_regs
; tem
; tem
= XEXP (tem
, 1))
5863 use_variable (XEXP (tem
, 0));
5864 use_variable_after (XEXP (tem
, 0), parm_birth_insn
);
5867 if (current_function_internal_arg_pointer
!= virtual_incoming_args_rtx
)
5868 use_variable (current_function_internal_arg_pointer
);
5871 clear_pending_stack_adjust ();
5872 do_pending_stack_adjust ();
5874 /* Mark the end of the function body.
5875 If control reaches this insn, the function can drop through
5876 without returning a value. */
5877 emit_note (NULL_PTR
, NOTE_INSN_FUNCTION_END
);
5879 /* Must mark the last line number note in the function, so that the test
5880 coverage code can avoid counting the last line twice. This just tells
5881 the code to ignore the immediately following line note, since there
5882 already exists a copy of this note somewhere above. This line number
5883 note is still needed for debugging though, so we can't delete it. */
5884 if (flag_test_coverage
)
5885 emit_note (NULL_PTR
, NOTE_REPEATED_LINE_NUMBER
);
5887 /* Output a linenumber for the end of the function.
5888 SDB depends on this. */
5889 emit_line_note_force (filename
, line
);
5891 /* Output the label for the actual return from the function,
5892 if one is expected. This happens either because a function epilogue
5893 is used instead of a return instruction, or because a return was done
5894 with a goto in order to run local cleanups, or because of pcc-style
5895 structure returning. */
5898 emit_label (return_label
);
5900 /* C++ uses this. */
5902 expand_end_bindings (0, 0, 0);
5904 /* Now handle any leftover exception regions that may have been
5905 created for the parameters. */
5907 rtx last
= get_last_insn ();
5910 expand_leftover_cleanups ();
5912 /* If the above emitted any code, may sure we jump around it. */
5913 if (last
!= get_last_insn ())
5915 label
= gen_label_rtx ();
5916 last
= emit_jump_insn_after (gen_jump (label
), last
);
5917 last
= emit_barrier_after (last
);
5922 if (current_function_instrument_entry_exit
)
5924 rtx fun
= DECL_RTL (current_function_decl
);
5925 if (GET_CODE (fun
) == MEM
)
5926 fun
= XEXP (fun
, 0);
5929 emit_library_call (profile_function_exit_libfunc
, 0, VOIDmode
, 2,
5931 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS
,
5933 hard_frame_pointer_rtx
),
5937 /* If we had calls to alloca, and this machine needs
5938 an accurate stack pointer to exit the function,
5939 insert some code to save and restore the stack pointer. */
5940 #ifdef EXIT_IGNORE_STACK
5941 if (! EXIT_IGNORE_STACK
)
5943 if (current_function_calls_alloca
)
5947 emit_stack_save (SAVE_FUNCTION
, &tem
, parm_birth_insn
);
5948 emit_stack_restore (SAVE_FUNCTION
, tem
, NULL_RTX
);
5951 /* If scalar return value was computed in a pseudo-reg,
5952 copy that to the hard return register. */
5953 if (DECL_RTL (DECL_RESULT (current_function_decl
)) != 0
5954 && GET_CODE (DECL_RTL (DECL_RESULT (current_function_decl
))) == REG
5955 && (REGNO (DECL_RTL (DECL_RESULT (current_function_decl
)))
5956 >= FIRST_PSEUDO_REGISTER
))
5958 rtx real_decl_result
;
5960 #ifdef FUNCTION_OUTGOING_VALUE
5962 = FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl
)),
5963 current_function_decl
);
5966 = FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl
)),
5967 current_function_decl
);
5969 REG_FUNCTION_VALUE_P (real_decl_result
) = 1;
5970 /* If this is a BLKmode structure being returned in registers, then use
5971 the mode computed in expand_return. */
5972 if (GET_MODE (real_decl_result
) == BLKmode
)
5973 PUT_MODE (real_decl_result
,
5974 GET_MODE (DECL_RTL (DECL_RESULT (current_function_decl
))));
5975 emit_move_insn (real_decl_result
,
5976 DECL_RTL (DECL_RESULT (current_function_decl
)));
5977 emit_insn (gen_rtx_USE (VOIDmode
, real_decl_result
));
5979 /* The delay slot scheduler assumes that current_function_return_rtx
5980 holds the hard register containing the return value, not a temporary
5982 current_function_return_rtx
= real_decl_result
;
5985 /* If returning a structure, arrange to return the address of the value
5986 in a place where debuggers expect to find it.
5988 If returning a structure PCC style,
5989 the caller also depends on this value.
5990 And current_function_returns_pcc_struct is not necessarily set. */
5991 if (current_function_returns_struct
5992 || current_function_returns_pcc_struct
)
5994 rtx value_address
= XEXP (DECL_RTL (DECL_RESULT (current_function_decl
)), 0);
5995 tree type
= TREE_TYPE (DECL_RESULT (current_function_decl
));
5996 #ifdef FUNCTION_OUTGOING_VALUE
5998 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type
),
5999 current_function_decl
);
6002 = FUNCTION_VALUE (build_pointer_type (type
),
6003 current_function_decl
);
6006 /* Mark this as a function return value so integrate will delete the
6007 assignment and USE below when inlining this function. */
6008 REG_FUNCTION_VALUE_P (outgoing
) = 1;
6010 emit_move_insn (outgoing
, value_address
);
6011 use_variable (outgoing
);
6014 /* If this is an implementation of __throw, do what's necessary to
6015 communicate between __builtin_eh_return and the epilogue. */
6016 expand_eh_return ();
6018 /* Output a return insn if we are using one.
6019 Otherwise, let the rtl chain end here, to drop through
6020 into the epilogue. */
6025 emit_jump_insn (gen_return ());
6030 /* Fix up any gotos that jumped out to the outermost
6031 binding level of the function.
6032 Must follow emitting RETURN_LABEL. */
6034 /* If you have any cleanups to do at this point,
6035 and they need to create temporary variables,
6036 then you will lose. */
6037 expand_fixups (get_insns ());
6040 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
6042 static int *prologue
;
6043 static int *epilogue
;
6045 /* Create an array that records the INSN_UIDs of INSNS (either a sequence
6046 or a single insn). */
6048 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
6050 record_insns (insns
)
6055 if (GET_CODE (insns
) == SEQUENCE
)
6057 int len
= XVECLEN (insns
, 0);
6058 vec
= (int *) oballoc ((len
+ 1) * sizeof (int));
6061 vec
[len
] = INSN_UID (XVECEXP (insns
, 0, len
));
6065 vec
= (int *) oballoc (2 * sizeof (int));
6066 vec
[0] = INSN_UID (insns
);
6072 /* Determine how many INSN_UIDs in VEC are part of INSN. */
6075 contains (insn
, vec
)
6081 if (GET_CODE (insn
) == INSN
6082 && GET_CODE (PATTERN (insn
)) == SEQUENCE
)
6085 for (i
= XVECLEN (PATTERN (insn
), 0) - 1; i
>= 0; i
--)
6086 for (j
= 0; vec
[j
]; j
++)
6087 if (INSN_UID (XVECEXP (PATTERN (insn
), 0, i
)) == vec
[j
])
6093 for (j
= 0; vec
[j
]; j
++)
6094 if (INSN_UID (insn
) == vec
[j
])
6099 #endif /* HAVE_prologue || HAVE_epilogue */
6101 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
6102 this into place with notes indicating where the prologue ends and where
6103 the epilogue begins. Update the basic block information when possible. */
6106 thread_prologue_and_epilogue_insns (f
)
6109 #ifdef HAVE_prologue
6114 /* The first insn (a NOTE_INSN_DELETED) is followed by zero or more
6115 prologue insns and a NOTE_INSN_PROLOGUE_END. */
6116 emit_note_after (NOTE_INSN_PROLOGUE_END
, f
);
6117 seq
= gen_prologue ();
6118 head
= emit_insn_after (seq
, f
);
6120 /* Include the new prologue insns in the first block. Ignore them
6121 if they form a basic block unto themselves. */
6122 if (basic_block_head
&& n_basic_blocks
6123 && GET_CODE (basic_block_head
[0]) != CODE_LABEL
)
6124 basic_block_head
[0] = NEXT_INSN (f
);
6126 /* Retain a map of the prologue insns. */
6127 prologue
= record_insns (GET_CODE (seq
) == SEQUENCE
? seq
: head
);
6133 #ifdef HAVE_epilogue
6136 rtx insn
= get_last_insn ();
6137 rtx prev
= prev_nonnote_insn (insn
);
6139 /* If we end with a BARRIER, we don't need an epilogue. */
6140 if (! (prev
&& GET_CODE (prev
) == BARRIER
))
6146 /* The last basic block ends with a NOTE_INSN_EPILOGUE_BEG, the
6147 epilogue insns, the USE insns at the end of a function,
6148 the jump insn that returns, and then a BARRIER. */
6150 /* Move the USE insns at the end of a function onto a list. */
6152 && GET_CODE (prev
) == INSN
6153 && GET_CODE (PATTERN (prev
)) == USE
)
6156 prev
= prev_nonnote_insn (prev
);
6158 NEXT_INSN (PREV_INSN (tem
)) = NEXT_INSN (tem
);
6159 PREV_INSN (NEXT_INSN (tem
)) = PREV_INSN (tem
);
6162 NEXT_INSN (tem
) = first_use
;
6163 PREV_INSN (first_use
) = tem
;
6170 emit_barrier_after (insn
);
6172 seq
= gen_epilogue ();
6173 tail
= emit_jump_insn_after (seq
, insn
);
6175 /* Insert the USE insns immediately before the return insn, which
6176 must be the first instruction before the final barrier. */
6179 tem
= prev_nonnote_insn (get_last_insn ());
6180 NEXT_INSN (PREV_INSN (tem
)) = first_use
;
6181 PREV_INSN (first_use
) = PREV_INSN (tem
);
6182 PREV_INSN (tem
) = last_use
;
6183 NEXT_INSN (last_use
) = tem
;
6186 emit_note_after (NOTE_INSN_EPILOGUE_BEG
, insn
);
6188 /* Include the new epilogue insns in the last block. Ignore
6189 them if they form a basic block unto themselves. */
6190 if (basic_block_end
&& n_basic_blocks
6191 && GET_CODE (basic_block_end
[n_basic_blocks
- 1]) != JUMP_INSN
)
6192 basic_block_end
[n_basic_blocks
- 1] = tail
;
6194 /* Retain a map of the epilogue insns. */
6195 epilogue
= record_insns (GET_CODE (seq
) == SEQUENCE
? seq
: tail
);
6203 /* Reposition the prologue-end and epilogue-begin notes after instruction
6204 scheduling and delayed branch scheduling. */
6207 reposition_prologue_and_epilogue_notes (f
)
6210 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
6211 /* Reposition the prologue and epilogue notes. */
6219 register rtx insn
, note
= 0;
6221 /* Scan from the beginning until we reach the last prologue insn.
6222 We apparently can't depend on basic_block_{head,end} after
6224 for (len
= 0; prologue
[len
]; len
++)
6226 for (insn
= f
; len
&& insn
; insn
= NEXT_INSN (insn
))
6228 if (GET_CODE (insn
) == NOTE
)
6230 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_PROLOGUE_END
)
6233 else if ((len
-= contains (insn
, prologue
)) == 0)
6235 /* Find the prologue-end note if we haven't already, and
6236 move it to just after the last prologue insn. */
6239 for (note
= insn
; (note
= NEXT_INSN (note
));)
6240 if (GET_CODE (note
) == NOTE
6241 && NOTE_LINE_NUMBER (note
) == NOTE_INSN_PROLOGUE_END
)
6245 next
= NEXT_INSN (note
);
6246 prev
= PREV_INSN (note
);
6248 NEXT_INSN (prev
) = next
;
6250 PREV_INSN (next
) = prev
;
6252 /* Whether or not we can depend on basic_block_head,
6253 attempt to keep it up-to-date. */
6254 if (basic_block_head
[0] == note
)
6255 basic_block_head
[0] = next
;
6257 add_insn_after (note
, insn
);
6264 register rtx insn
, note
= 0;
6266 /* Scan from the end until we reach the first epilogue insn.
6267 We apparently can't depend on basic_block_{head,end} after
6269 for (len
= 0; epilogue
[len
]; len
++)
6271 for (insn
= get_last_insn (); len
&& insn
; insn
= PREV_INSN (insn
))
6273 if (GET_CODE (insn
) == NOTE
)
6275 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_EPILOGUE_BEG
)
6278 else if ((len
-= contains (insn
, epilogue
)) == 0)
6280 /* Find the epilogue-begin note if we haven't already, and
6281 move it to just before the first epilogue insn. */
6284 for (note
= insn
; (note
= PREV_INSN (note
));)
6285 if (GET_CODE (note
) == NOTE
6286 && NOTE_LINE_NUMBER (note
) == NOTE_INSN_EPILOGUE_BEG
)
6289 next
= NEXT_INSN (note
);
6290 prev
= PREV_INSN (note
);
6292 NEXT_INSN (prev
) = next
;
6294 PREV_INSN (next
) = prev
;
6296 /* Whether or not we can depend on basic_block_head,
6297 attempt to keep it up-to-date. */
6299 && basic_block_head
[n_basic_blocks
-1] == insn
)
6300 basic_block_head
[n_basic_blocks
-1] = note
;
6302 add_insn_before (note
, insn
);
6307 #endif /* HAVE_prologue or HAVE_epilogue */