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. */
51 #include "insn-flags.h"
53 #include "insn-codes.h"
55 #include "hard-reg-set.h"
56 #include "insn-config.h"
59 #include "basic-block.h"
62 #ifndef TRAMPOLINE_ALIGNMENT
63 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
66 /* Some systems use __main in a way incompatible with its use in gcc, in these
67 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
68 give the same symbol without quotes for an alternative entry point. You
69 must define both, or neither. */
71 #define NAME__MAIN "__main"
72 #define SYMBOL__MAIN __main
75 /* Round a value to the lowest integer less than it that is a multiple of
76 the required alignment. Avoid using division in case the value is
77 negative. Assume the alignment is a power of two. */
78 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
80 /* Similar, but round to the next highest integer that meets the
82 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
84 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
85 during rtl generation. If they are different register numbers, this is
86 always true. It may also be true if
87 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
88 generation. See fix_lexical_addr for details. */
90 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
91 #define NEED_SEPARATE_AP
94 /* Number of bytes of args popped by function being compiled on its return.
95 Zero if no bytes are to be popped.
96 May affect compilation of return insn or of function epilogue. */
98 int current_function_pops_args
;
100 /* Nonzero if function being compiled needs to be given an address
101 where the value should be stored. */
103 int current_function_returns_struct
;
105 /* Nonzero if function being compiled needs to
106 return the address of where it has put a structure value. */
108 int current_function_returns_pcc_struct
;
110 /* Nonzero if function being compiled needs to be passed a static chain. */
112 int current_function_needs_context
;
114 /* Nonzero if function being compiled can call setjmp. */
116 int current_function_calls_setjmp
;
118 /* Nonzero if function being compiled can call longjmp. */
120 int current_function_calls_longjmp
;
122 /* Nonzero if function being compiled receives nonlocal gotos
123 from nested functions. */
125 int current_function_has_nonlocal_label
;
127 /* Nonzero if function being compiled has nonlocal gotos to parent
130 int current_function_has_nonlocal_goto
;
132 /* Nonzero if function being compiled contains nested functions. */
134 int current_function_contains_functions
;
136 /* Nonzero if the current function is a thunk (a lightweight function that
137 just adjusts one of its arguments and forwards to another function), so
138 we should try to cut corners where we can. */
139 int current_function_is_thunk
;
141 /* Nonzero if function being compiled can call alloca,
142 either as a subroutine or builtin. */
144 int current_function_calls_alloca
;
146 /* Nonzero if the current function returns a pointer type */
148 int current_function_returns_pointer
;
150 /* If some insns can be deferred to the delay slots of the epilogue, the
151 delay list for them is recorded here. */
153 rtx current_function_epilogue_delay_list
;
155 /* If function's args have a fixed size, this is that size, in bytes.
157 May affect compilation of return insn or of function epilogue. */
159 int current_function_args_size
;
161 /* # bytes the prologue should push and pretend that the caller pushed them.
162 The prologue must do this, but only if parms can be passed in registers. */
164 int current_function_pretend_args_size
;
166 /* # of bytes of outgoing arguments. If ACCUMULATE_OUTGOING_ARGS is
167 defined, the needed space is pushed by the prologue. */
169 int current_function_outgoing_args_size
;
171 /* This is the offset from the arg pointer to the place where the first
172 anonymous arg can be found, if there is one. */
174 rtx current_function_arg_offset_rtx
;
176 /* Nonzero if current function uses varargs.h or equivalent.
177 Zero for functions that use stdarg.h. */
179 int current_function_varargs
;
181 /* Nonzero if current function uses stdarg.h or equivalent.
182 Zero for functions that use varargs.h. */
184 int current_function_stdarg
;
186 /* Quantities of various kinds of registers
187 used for the current function's args. */
189 CUMULATIVE_ARGS current_function_args_info
;
191 /* Name of function now being compiled. */
193 char *current_function_name
;
195 /* If non-zero, an RTL expression for the location at which the current
196 function returns its result. If the current function returns its
197 result in a register, current_function_return_rtx will always be
198 the hard register containing the result. */
200 rtx current_function_return_rtx
;
202 /* Nonzero if the current function uses the constant pool. */
204 int current_function_uses_const_pool
;
206 /* Nonzero if the current function uses pic_offset_table_rtx. */
207 int current_function_uses_pic_offset_table
;
209 /* The arg pointer hard register, or the pseudo into which it was copied. */
210 rtx current_function_internal_arg_pointer
;
212 /* The FUNCTION_DECL for an inline function currently being expanded. */
213 tree inline_function_decl
;
215 /* Number of function calls seen so far in current function. */
217 int function_call_count
;
219 /* List (chain of TREE_LIST) of LABEL_DECLs for all nonlocal labels
220 (labels to which there can be nonlocal gotos from nested functions)
223 tree nonlocal_labels
;
225 /* RTX for stack slot that holds the current handler for nonlocal gotos.
226 Zero when function does not have nonlocal labels. */
228 rtx nonlocal_goto_handler_slot
;
230 /* RTX for stack slot that holds the stack pointer value to restore
232 Zero when function does not have nonlocal labels. */
234 rtx nonlocal_goto_stack_level
;
236 /* Label that will go on parm cleanup code, if any.
237 Jumping to this label runs cleanup code for parameters, if
238 such code must be run. Following this code is the logical return label. */
242 /* Label that will go on function epilogue.
243 Jumping to this label serves as a "return" instruction
244 on machines which require execution of the epilogue on all returns. */
248 /* List (chain of EXPR_LISTs) of pseudo-regs of SAVE_EXPRs.
249 So we can mark them all live at the end of the function, if nonopt. */
252 /* List (chain of EXPR_LISTs) of all stack slots in this function.
253 Made for the sake of unshare_all_rtl. */
256 /* Chain of all RTL_EXPRs that have insns in them. */
259 /* Label to jump back to for tail recursion, or 0 if we have
260 not yet needed one for this function. */
261 rtx tail_recursion_label
;
263 /* Place after which to insert the tail_recursion_label if we need one. */
264 rtx tail_recursion_reentry
;
266 /* Location at which to save the argument pointer if it will need to be
267 referenced. There are two cases where this is done: if nonlocal gotos
268 exist, or if vars stored at an offset from the argument pointer will be
269 needed by inner routines. */
271 rtx arg_pointer_save_area
;
273 /* Offset to end of allocated area of stack frame.
274 If stack grows down, this is the address of the last stack slot allocated.
275 If stack grows up, this is the address for the next slot. */
276 HOST_WIDE_INT frame_offset
;
278 /* List (chain of TREE_LISTs) of static chains for containing functions.
279 Each link has a FUNCTION_DECL in the TREE_PURPOSE and a reg rtx
280 in an RTL_EXPR in the TREE_VALUE. */
281 static tree context_display
;
283 /* List (chain of TREE_LISTs) of trampolines for nested functions.
284 The trampoline sets up the static chain and jumps to the function.
285 We supply the trampoline's address when the function's address is requested.
287 Each link has a FUNCTION_DECL in the TREE_PURPOSE and a reg rtx
288 in an RTL_EXPR in the TREE_VALUE. */
289 static tree trampoline_list
;
291 /* Insn after which register parms and SAVE_EXPRs are born, if nonopt. */
292 static rtx parm_birth_insn
;
295 /* Nonzero if a stack slot has been generated whose address is not
296 actually valid. It means that the generated rtl must all be scanned
297 to detect and correct the invalid addresses where they occur. */
298 static int invalid_stack_slot
;
301 /* Last insn of those whose job was to put parms into their nominal homes. */
302 static rtx last_parm_insn
;
304 /* 1 + last pseudo register number possibly used for loading a copy
305 of a parameter of this function. */
308 /* Vector indexed by REGNO, containing location on stack in which
309 to put the parm which is nominally in pseudo register REGNO,
310 if we discover that that parm must go in the stack. The highest
311 element in this vector is one less than MAX_PARM_REG, above. */
312 rtx
*parm_reg_stack_loc
;
314 /* Nonzero once virtual register instantiation has been done.
315 assign_stack_local uses frame_pointer_rtx when this is nonzero. */
316 static int virtuals_instantiated
;
318 /* These variables hold pointers to functions to
319 save and restore machine-specific data,
320 in push_function_context and pop_function_context. */
321 void (*save_machine_status
) PROTO((struct function
*));
322 void (*restore_machine_status
) PROTO((struct function
*));
324 /* Nonzero if we need to distinguish between the return value of this function
325 and the return value of a function called by this function. This helps
328 extern int rtx_equal_function_value_matters
;
329 extern tree sequence_rtl_expr
;
331 /* In order to evaluate some expressions, such as function calls returning
332 structures in memory, we need to temporarily allocate stack locations.
333 We record each allocated temporary in the following structure.
335 Associated with each temporary slot is a nesting level. When we pop up
336 one level, all temporaries associated with the previous level are freed.
337 Normally, all temporaries are freed after the execution of the statement
338 in which they were created. However, if we are inside a ({...}) grouping,
339 the result may be in a temporary and hence must be preserved. If the
340 result could be in a temporary, we preserve it if we can determine which
341 one it is in. If we cannot determine which temporary may contain the
342 result, all temporaries are preserved. A temporary is preserved by
343 pretending it was allocated at the previous nesting level.
345 Automatic variables are also assigned temporary slots, at the nesting
346 level where they are defined. They are marked a "kept" so that
347 free_temp_slots will not free them. */
351 /* Points to next temporary slot. */
352 struct temp_slot
*next
;
353 /* The rtx to used to reference the slot. */
355 /* The rtx used to represent the address if not the address of the
356 slot above. May be an EXPR_LIST if multiple addresses exist. */
358 /* The size, in units, of the slot. */
360 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
362 /* Non-zero if this temporary is currently in use. */
364 /* Non-zero if this temporary has its address taken. */
366 /* Nesting level at which this slot is being used. */
368 /* Non-zero if this should survive a call to free_temp_slots. */
370 /* The offset of the slot from the frame_pointer, including extra space
371 for alignment. This info is for combine_temp_slots. */
373 /* The size of the slot, including extra space for alignment. This
374 info is for combine_temp_slots. */
378 /* List of all temporaries allocated, both available and in use. */
380 struct temp_slot
*temp_slots
;
382 /* Current nesting level for temporaries. */
386 /* This structure is used to record MEMs or pseudos used to replace VAR, any
387 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
388 maintain this list in case two operands of an insn were required to match;
389 in that case we must ensure we use the same replacement. */
391 struct fixup_replacement
395 struct fixup_replacement
*next
;
398 /* Forward declarations. */
400 static struct temp_slot
*find_temp_slot_from_address
PROTO((rtx
));
401 static void put_reg_into_stack
PROTO((struct function
*, rtx
, tree
,
402 enum machine_mode
, enum machine_mode
,
404 static void fixup_var_refs
PROTO((rtx
, enum machine_mode
, int));
405 static struct fixup_replacement
406 *find_fixup_replacement
PROTO((struct fixup_replacement
**, rtx
));
407 static void fixup_var_refs_insns
PROTO((rtx
, enum machine_mode
, int,
409 static void fixup_var_refs_1
PROTO((rtx
, enum machine_mode
, rtx
*, rtx
,
410 struct fixup_replacement
**));
411 static rtx fixup_memory_subreg
PROTO((rtx
, rtx
, int));
412 static rtx walk_fixup_memory_subreg
PROTO((rtx
, rtx
, int));
413 static rtx fixup_stack_1
PROTO((rtx
, rtx
));
414 static void optimize_bit_field
PROTO((rtx
, rtx
, rtx
*));
415 static void instantiate_decls
PROTO((tree
, int));
416 static void instantiate_decls_1
PROTO((tree
, int));
417 static void instantiate_decl
PROTO((rtx
, int, int));
418 static int instantiate_virtual_regs_1
PROTO((rtx
*, rtx
, int));
419 static void delete_handlers
PROTO((void));
420 static void pad_to_arg_alignment
PROTO((struct args_size
*, int));
421 #ifndef ARGS_GROW_DOWNWARD
422 static void pad_below
PROTO((struct args_size
*, enum machine_mode
,
425 static tree round_down
PROTO((tree
, int));
426 static rtx round_trampoline_addr
PROTO((rtx
));
427 static tree blocks_nreverse
PROTO((tree
));
428 static int all_blocks
PROTO((tree
, tree
*));
429 static int *record_insns
PROTO((rtx
));
430 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
431 static int contains
PROTO((rtx
, int *));
432 #endif /* HAVE_prologue || HAVE_epilogue */
433 static void put_addressof_into_stack
PROTO((rtx
));
434 static void purge_addressof_1
PROTO((rtx
*, rtx
, int));
436 /* Pointer to chain of `struct function' for containing functions. */
437 struct function
*outer_function_chain
;
439 /* Given a function decl for a containing function,
440 return the `struct function' for it. */
443 find_function_data (decl
)
447 for (p
= outer_function_chain
; p
; p
= p
->next
)
453 /* Save the current context for compilation of a nested function.
454 This is called from language-specific code.
455 The caller is responsible for saving any language-specific status,
456 since this function knows only about language-independent variables. */
459 push_function_context_to (context
)
462 struct function
*p
= (struct function
*) xmalloc (sizeof (struct function
));
464 p
->next
= outer_function_chain
;
465 outer_function_chain
= p
;
467 p
->name
= current_function_name
;
468 p
->decl
= current_function_decl
;
469 p
->pops_args
= current_function_pops_args
;
470 p
->returns_struct
= current_function_returns_struct
;
471 p
->returns_pcc_struct
= current_function_returns_pcc_struct
;
472 p
->returns_pointer
= current_function_returns_pointer
;
473 p
->needs_context
= current_function_needs_context
;
474 p
->calls_setjmp
= current_function_calls_setjmp
;
475 p
->calls_longjmp
= current_function_calls_longjmp
;
476 p
->calls_alloca
= current_function_calls_alloca
;
477 p
->has_nonlocal_label
= current_function_has_nonlocal_label
;
478 p
->has_nonlocal_goto
= current_function_has_nonlocal_goto
;
479 p
->contains_functions
= current_function_contains_functions
;
480 p
->is_thunk
= current_function_is_thunk
;
481 p
->args_size
= current_function_args_size
;
482 p
->pretend_args_size
= current_function_pretend_args_size
;
483 p
->arg_offset_rtx
= current_function_arg_offset_rtx
;
484 p
->varargs
= current_function_varargs
;
485 p
->stdarg
= current_function_stdarg
;
486 p
->uses_const_pool
= current_function_uses_const_pool
;
487 p
->uses_pic_offset_table
= current_function_uses_pic_offset_table
;
488 p
->internal_arg_pointer
= current_function_internal_arg_pointer
;
489 p
->max_parm_reg
= max_parm_reg
;
490 p
->parm_reg_stack_loc
= parm_reg_stack_loc
;
491 p
->outgoing_args_size
= current_function_outgoing_args_size
;
492 p
->return_rtx
= current_function_return_rtx
;
493 p
->nonlocal_goto_handler_slot
= nonlocal_goto_handler_slot
;
494 p
->nonlocal_goto_stack_level
= nonlocal_goto_stack_level
;
495 p
->nonlocal_labels
= nonlocal_labels
;
496 p
->cleanup_label
= cleanup_label
;
497 p
->return_label
= return_label
;
498 p
->save_expr_regs
= save_expr_regs
;
499 p
->stack_slot_list
= stack_slot_list
;
500 p
->parm_birth_insn
= parm_birth_insn
;
501 p
->frame_offset
= frame_offset
;
502 p
->tail_recursion_label
= tail_recursion_label
;
503 p
->tail_recursion_reentry
= tail_recursion_reentry
;
504 p
->arg_pointer_save_area
= arg_pointer_save_area
;
505 p
->rtl_expr_chain
= rtl_expr_chain
;
506 p
->last_parm_insn
= last_parm_insn
;
507 p
->context_display
= context_display
;
508 p
->trampoline_list
= trampoline_list
;
509 p
->function_call_count
= function_call_count
;
510 p
->temp_slots
= temp_slots
;
511 p
->temp_slot_level
= temp_slot_level
;
512 p
->fixup_var_refs_queue
= 0;
513 p
->epilogue_delay_list
= current_function_epilogue_delay_list
;
514 p
->args_info
= current_function_args_info
;
516 save_tree_status (p
, context
);
517 save_storage_status (p
);
518 save_emit_status (p
);
519 save_expr_status (p
);
520 save_stmt_status (p
);
521 save_varasm_status (p
, context
);
523 if (save_machine_status
)
524 (*save_machine_status
) (p
);
528 push_function_context ()
530 push_function_context_to (current_function_decl
);
533 /* Restore the last saved context, at the end of a nested function.
534 This function is called from language-specific code. */
537 pop_function_context_from (context
)
540 struct function
*p
= outer_function_chain
;
542 outer_function_chain
= p
->next
;
544 current_function_contains_functions
545 = p
->contains_functions
|| p
->inline_obstacks
546 || context
== current_function_decl
;
547 current_function_name
= p
->name
;
548 current_function_decl
= p
->decl
;
549 current_function_pops_args
= p
->pops_args
;
550 current_function_returns_struct
= p
->returns_struct
;
551 current_function_returns_pcc_struct
= p
->returns_pcc_struct
;
552 current_function_returns_pointer
= p
->returns_pointer
;
553 current_function_needs_context
= p
->needs_context
;
554 current_function_calls_setjmp
= p
->calls_setjmp
;
555 current_function_calls_longjmp
= p
->calls_longjmp
;
556 current_function_calls_alloca
= p
->calls_alloca
;
557 current_function_has_nonlocal_label
= p
->has_nonlocal_label
;
558 current_function_has_nonlocal_goto
= p
->has_nonlocal_goto
;
559 current_function_is_thunk
= p
->is_thunk
;
560 current_function_args_size
= p
->args_size
;
561 current_function_pretend_args_size
= p
->pretend_args_size
;
562 current_function_arg_offset_rtx
= p
->arg_offset_rtx
;
563 current_function_varargs
= p
->varargs
;
564 current_function_stdarg
= p
->stdarg
;
565 current_function_uses_const_pool
= p
->uses_const_pool
;
566 current_function_uses_pic_offset_table
= p
->uses_pic_offset_table
;
567 current_function_internal_arg_pointer
= p
->internal_arg_pointer
;
568 max_parm_reg
= p
->max_parm_reg
;
569 parm_reg_stack_loc
= p
->parm_reg_stack_loc
;
570 current_function_outgoing_args_size
= p
->outgoing_args_size
;
571 current_function_return_rtx
= p
->return_rtx
;
572 nonlocal_goto_handler_slot
= p
->nonlocal_goto_handler_slot
;
573 nonlocal_goto_stack_level
= p
->nonlocal_goto_stack_level
;
574 nonlocal_labels
= p
->nonlocal_labels
;
575 cleanup_label
= p
->cleanup_label
;
576 return_label
= p
->return_label
;
577 save_expr_regs
= p
->save_expr_regs
;
578 stack_slot_list
= p
->stack_slot_list
;
579 parm_birth_insn
= p
->parm_birth_insn
;
580 frame_offset
= p
->frame_offset
;
581 tail_recursion_label
= p
->tail_recursion_label
;
582 tail_recursion_reentry
= p
->tail_recursion_reentry
;
583 arg_pointer_save_area
= p
->arg_pointer_save_area
;
584 rtl_expr_chain
= p
->rtl_expr_chain
;
585 last_parm_insn
= p
->last_parm_insn
;
586 context_display
= p
->context_display
;
587 trampoline_list
= p
->trampoline_list
;
588 function_call_count
= p
->function_call_count
;
589 temp_slots
= p
->temp_slots
;
590 temp_slot_level
= p
->temp_slot_level
;
591 current_function_epilogue_delay_list
= p
->epilogue_delay_list
;
593 current_function_args_info
= p
->args_info
;
595 restore_tree_status (p
, context
);
596 restore_storage_status (p
);
597 restore_expr_status (p
);
598 restore_emit_status (p
);
599 restore_stmt_status (p
);
600 restore_varasm_status (p
);
602 if (restore_machine_status
)
603 (*restore_machine_status
) (p
);
605 /* Finish doing put_var_into_stack for any of our variables
606 which became addressable during the nested function. */
608 struct var_refs_queue
*queue
= p
->fixup_var_refs_queue
;
609 for (; queue
; queue
= queue
->next
)
610 fixup_var_refs (queue
->modified
, queue
->promoted_mode
, queue
->unsignedp
);
615 /* Reset variables that have known state during rtx generation. */
616 rtx_equal_function_value_matters
= 1;
617 virtuals_instantiated
= 0;
620 void pop_function_context ()
622 pop_function_context_from (current_function_decl
);
625 /* Allocate fixed slots in the stack frame of the current function. */
627 /* Return size needed for stack frame based on slots so far allocated.
628 This size counts from zero. It is not rounded to STACK_BOUNDARY;
629 the caller may have to do that. */
634 #ifdef FRAME_GROWS_DOWNWARD
635 return -frame_offset
;
641 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
642 with machine mode MODE.
644 ALIGN controls the amount of alignment for the address of the slot:
645 0 means according to MODE,
646 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
647 positive specifies alignment boundary in bits.
649 We do not round to stack_boundary here. */
652 assign_stack_local (mode
, size
, align
)
653 enum machine_mode mode
;
657 register rtx x
, addr
;
658 int bigend_correction
= 0;
663 alignment
= GET_MODE_ALIGNMENT (mode
) / BITS_PER_UNIT
;
665 alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
667 else if (align
== -1)
669 alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
670 size
= CEIL_ROUND (size
, alignment
);
673 alignment
= align
/ BITS_PER_UNIT
;
675 /* Round frame offset to that alignment.
676 We must be careful here, since FRAME_OFFSET might be negative and
677 division with a negative dividend isn't as well defined as we might
678 like. So we instead assume that ALIGNMENT is a power of two and
679 use logical operations which are unambiguous. */
680 #ifdef FRAME_GROWS_DOWNWARD
681 frame_offset
= FLOOR_ROUND (frame_offset
, alignment
);
683 frame_offset
= CEIL_ROUND (frame_offset
, alignment
);
686 /* On a big-endian machine, if we are allocating more space than we will use,
687 use the least significant bytes of those that are allocated. */
688 if (BYTES_BIG_ENDIAN
&& mode
!= BLKmode
)
689 bigend_correction
= size
- GET_MODE_SIZE (mode
);
691 #ifdef FRAME_GROWS_DOWNWARD
692 frame_offset
-= size
;
695 /* If we have already instantiated virtual registers, return the actual
696 address relative to the frame pointer. */
697 if (virtuals_instantiated
)
698 addr
= plus_constant (frame_pointer_rtx
,
699 (frame_offset
+ bigend_correction
700 + STARTING_FRAME_OFFSET
));
702 addr
= plus_constant (virtual_stack_vars_rtx
,
703 frame_offset
+ bigend_correction
);
705 #ifndef FRAME_GROWS_DOWNWARD
706 frame_offset
+= size
;
709 x
= gen_rtx_MEM (mode
, addr
);
711 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, x
, stack_slot_list
);
716 /* Assign a stack slot in a containing function.
717 First three arguments are same as in preceding function.
718 The last argument specifies the function to allocate in. */
721 assign_outer_stack_local (mode
, size
, align
, function
)
722 enum machine_mode mode
;
725 struct function
*function
;
727 register rtx x
, addr
;
728 int bigend_correction
= 0;
731 /* Allocate in the memory associated with the function in whose frame
733 push_obstacks (function
->function_obstack
,
734 function
->function_maybepermanent_obstack
);
738 alignment
= GET_MODE_ALIGNMENT (mode
) / BITS_PER_UNIT
;
740 alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
742 else if (align
== -1)
744 alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
745 size
= CEIL_ROUND (size
, alignment
);
748 alignment
= align
/ BITS_PER_UNIT
;
750 /* Round frame offset to that alignment. */
751 #ifdef FRAME_GROWS_DOWNWARD
752 function
->frame_offset
= FLOOR_ROUND (function
->frame_offset
, alignment
);
754 function
->frame_offset
= CEIL_ROUND (function
->frame_offset
, alignment
);
757 /* On a big-endian machine, if we are allocating more space than we will use,
758 use the least significant bytes of those that are allocated. */
759 if (BYTES_BIG_ENDIAN
&& mode
!= BLKmode
)
760 bigend_correction
= size
- GET_MODE_SIZE (mode
);
762 #ifdef FRAME_GROWS_DOWNWARD
763 function
->frame_offset
-= size
;
765 addr
= plus_constant (virtual_stack_vars_rtx
,
766 function
->frame_offset
+ bigend_correction
);
767 #ifndef FRAME_GROWS_DOWNWARD
768 function
->frame_offset
+= size
;
771 x
= gen_rtx_MEM (mode
, addr
);
773 function
->stack_slot_list
774 = gen_rtx_EXPR_LIST (VOIDmode
, x
, function
->stack_slot_list
);
781 /* Allocate a temporary stack slot and record it for possible later
784 MODE is the machine mode to be given to the returned rtx.
786 SIZE is the size in units of the space required. We do no rounding here
787 since assign_stack_local will do any required rounding.
789 KEEP is 1 if this slot is to be retained after a call to
790 free_temp_slots. Automatic variables for a block are allocated
791 with this flag. KEEP is 2, if we allocate a longer term temporary,
792 whose lifetime is controlled by CLEANUP_POINT_EXPRs. */
795 assign_stack_temp (mode
, size
, keep
)
796 enum machine_mode mode
;
800 struct temp_slot
*p
, *best_p
= 0;
802 /* If SIZE is -1 it means that somebody tried to allocate a temporary
803 of a variable size. */
807 /* First try to find an available, already-allocated temporary that is the
808 exact size we require. */
809 for (p
= temp_slots
; p
; p
= p
->next
)
810 if (p
->size
== size
&& GET_MODE (p
->slot
) == mode
&& ! p
->in_use
)
813 /* If we didn't find, one, try one that is larger than what we want. We
814 find the smallest such. */
816 for (p
= temp_slots
; p
; p
= p
->next
)
817 if (p
->size
> size
&& GET_MODE (p
->slot
) == mode
&& ! p
->in_use
818 && (best_p
== 0 || best_p
->size
> p
->size
))
821 /* Make our best, if any, the one to use. */
824 /* If there are enough aligned bytes left over, make them into a new
825 temp_slot so that the extra bytes don't get wasted. Do this only
826 for BLKmode slots, so that we can be sure of the alignment. */
827 if (GET_MODE (best_p
->slot
) == BLKmode
)
829 int alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
830 int rounded_size
= CEIL_ROUND (size
, alignment
);
832 if (best_p
->size
- rounded_size
>= alignment
)
834 p
= (struct temp_slot
*) oballoc (sizeof (struct temp_slot
));
835 p
->in_use
= p
->addr_taken
= 0;
836 p
->size
= best_p
->size
- rounded_size
;
837 p
->base_offset
= best_p
->base_offset
+ rounded_size
;
838 p
->full_size
= best_p
->full_size
- rounded_size
;
839 p
->slot
= gen_rtx_MEM (BLKmode
,
840 plus_constant (XEXP (best_p
->slot
, 0),
844 p
->next
= temp_slots
;
847 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, p
->slot
,
850 best_p
->size
= rounded_size
;
851 best_p
->full_size
= rounded_size
;
858 /* If we still didn't find one, make a new temporary. */
861 int frame_offset_old
= frame_offset
;
862 p
= (struct temp_slot
*) oballoc (sizeof (struct temp_slot
));
863 /* If the temp slot mode doesn't indicate the alignment,
864 use the largest possible, so no one will be disappointed. */
865 p
->slot
= assign_stack_local (mode
, size
, mode
== BLKmode
? -1 : 0);
866 /* The following slot size computation is necessary because we don't
867 know the actual size of the temporary slot until assign_stack_local
868 has performed all the frame alignment and size rounding for the
869 requested temporary. Note that extra space added for alignment
870 can be either above or below this stack slot depending on which
871 way the frame grows. We include the extra space if and only if it
872 is above this slot. */
873 #ifdef FRAME_GROWS_DOWNWARD
874 p
->size
= frame_offset_old
- frame_offset
;
878 /* Now define the fields used by combine_temp_slots. */
879 #ifdef FRAME_GROWS_DOWNWARD
880 p
->base_offset
= frame_offset
;
881 p
->full_size
= frame_offset_old
- frame_offset
;
883 p
->base_offset
= frame_offset_old
;
884 p
->full_size
= frame_offset
- frame_offset_old
;
887 p
->next
= temp_slots
;
893 p
->rtl_expr
= sequence_rtl_expr
;
897 p
->level
= target_temp_slot_level
;
902 p
->level
= temp_slot_level
;
906 /* We may be reusing an old slot, so clear any MEM flags that may have been
908 RTX_UNCHANGING_P (p
->slot
) = 0;
909 MEM_IN_STRUCT_P (p
->slot
) = 0;
913 /* Assign a temporary of given TYPE.
914 KEEP is as for assign_stack_temp.
915 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
916 it is 0 if a register is OK.
917 DONT_PROMOTE is 1 if we should not promote values in register
921 assign_temp (type
, keep
, memory_required
, dont_promote
)
927 enum machine_mode mode
= TYPE_MODE (type
);
928 int unsignedp
= TREE_UNSIGNED (type
);
930 if (mode
== BLKmode
|| memory_required
)
932 int size
= int_size_in_bytes (type
);
935 /* Unfortunately, we don't yet know how to allocate variable-sized
936 temporaries. However, sometimes we have a fixed upper limit on
937 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
938 instead. This is the case for Chill variable-sized strings. */
939 if (size
== -1 && TREE_CODE (type
) == ARRAY_TYPE
940 && TYPE_ARRAY_MAX_SIZE (type
) != NULL_TREE
941 && TREE_CODE (TYPE_ARRAY_MAX_SIZE (type
)) == INTEGER_CST
)
942 size
= TREE_INT_CST_LOW (TYPE_ARRAY_MAX_SIZE (type
));
944 tmp
= assign_stack_temp (mode
, size
, keep
);
945 MEM_IN_STRUCT_P (tmp
) = AGGREGATE_TYPE_P (type
);
949 #ifndef PROMOTE_FOR_CALL_ONLY
951 mode
= promote_mode (type
, mode
, &unsignedp
, 0);
954 return gen_reg_rtx (mode
);
957 /* Combine temporary stack slots which are adjacent on the stack.
959 This allows for better use of already allocated stack space. This is only
960 done for BLKmode slots because we can be sure that we won't have alignment
961 problems in this case. */
964 combine_temp_slots ()
966 struct temp_slot
*p
, *q
;
967 struct temp_slot
*prev_p
, *prev_q
;
968 /* Determine where to free back to after this function. */
969 rtx free_pointer
= rtx_alloc (CONST_INT
);
971 for (p
= temp_slots
, prev_p
= 0; p
; p
= prev_p
? prev_p
->next
: temp_slots
)
974 if (! p
->in_use
&& GET_MODE (p
->slot
) == BLKmode
)
975 for (q
= p
->next
, prev_q
= p
; q
; q
= prev_q
->next
)
978 if (! q
->in_use
&& GET_MODE (q
->slot
) == BLKmode
)
980 if (p
->base_offset
+ p
->full_size
== q
->base_offset
)
982 /* Q comes after P; combine Q into P. */
984 p
->full_size
+= q
->full_size
;
987 else if (q
->base_offset
+ q
->full_size
== p
->base_offset
)
989 /* P comes after Q; combine P into Q. */
991 q
->full_size
+= p
->full_size
;
996 /* Either delete Q or advance past it. */
998 prev_q
->next
= q
->next
;
1002 /* Either delete P or advance past it. */
1006 prev_p
->next
= p
->next
;
1008 temp_slots
= p
->next
;
1014 /* Free all the RTL made by plus_constant. */
1015 rtx_free (free_pointer
);
1018 /* Find the temp slot corresponding to the object at address X. */
1020 static struct temp_slot
*
1021 find_temp_slot_from_address (x
)
1024 struct temp_slot
*p
;
1027 for (p
= temp_slots
; p
; p
= p
->next
)
1031 else if (XEXP (p
->slot
, 0) == x
1033 || (GET_CODE (x
) == PLUS
1034 && XEXP (x
, 0) == virtual_stack_vars_rtx
1035 && GET_CODE (XEXP (x
, 1)) == CONST_INT
1036 && INTVAL (XEXP (x
, 1)) >= p
->base_offset
1037 && INTVAL (XEXP (x
, 1)) < p
->base_offset
+ p
->full_size
))
1040 else if (p
->address
!= 0 && GET_CODE (p
->address
) == EXPR_LIST
)
1041 for (next
= p
->address
; next
; next
= XEXP (next
, 1))
1042 if (XEXP (next
, 0) == x
)
1049 /* Indicate that NEW is an alternate way of referring to the temp slot
1050 that previous was known by OLD. */
1053 update_temp_slot_address (old
, new)
1056 struct temp_slot
*p
= find_temp_slot_from_address (old
);
1058 /* If none, return. Else add NEW as an alias. */
1061 else if (p
->address
== 0)
1065 if (GET_CODE (p
->address
) != EXPR_LIST
)
1066 p
->address
= gen_rtx_EXPR_LIST (VOIDmode
, p
->address
, NULL_RTX
);
1068 p
->address
= gen_rtx_EXPR_LIST (VOIDmode
, new, p
->address
);
1072 /* If X could be a reference to a temporary slot, mark the fact that its
1073 address was taken. */
1076 mark_temp_addr_taken (x
)
1079 struct temp_slot
*p
;
1084 /* If X is not in memory or is at a constant address, it cannot be in
1085 a temporary slot. */
1086 if (GET_CODE (x
) != MEM
|| CONSTANT_P (XEXP (x
, 0)))
1089 p
= find_temp_slot_from_address (XEXP (x
, 0));
1094 /* If X could be a reference to a temporary slot, mark that slot as
1095 belonging to the to one level higher than the current level. If X
1096 matched one of our slots, just mark that one. Otherwise, we can't
1097 easily predict which it is, so upgrade all of them. Kept slots
1098 need not be touched.
1100 This is called when an ({...}) construct occurs and a statement
1101 returns a value in memory. */
1104 preserve_temp_slots (x
)
1107 struct temp_slot
*p
= 0;
1109 /* If there is no result, we still might have some objects whose address
1110 were taken, so we need to make sure they stay around. */
1113 for (p
= temp_slots
; p
; p
= p
->next
)
1114 if (p
->in_use
&& p
->level
== temp_slot_level
&& p
->addr_taken
)
1120 /* If X is a register that is being used as a pointer, see if we have
1121 a temporary slot we know it points to. To be consistent with
1122 the code below, we really should preserve all non-kept slots
1123 if we can't find a match, but that seems to be much too costly. */
1124 if (GET_CODE (x
) == REG
&& REGNO_POINTER_FLAG (REGNO (x
)))
1125 p
= find_temp_slot_from_address (x
);
1127 /* If X is not in memory or is at a constant address, it cannot be in
1128 a temporary slot, but it can contain something whose address was
1130 if (p
== 0 && (GET_CODE (x
) != MEM
|| CONSTANT_P (XEXP (x
, 0))))
1132 for (p
= temp_slots
; p
; p
= p
->next
)
1133 if (p
->in_use
&& p
->level
== temp_slot_level
&& p
->addr_taken
)
1139 /* First see if we can find a match. */
1141 p
= find_temp_slot_from_address (XEXP (x
, 0));
1145 /* Move everything at our level whose address was taken to our new
1146 level in case we used its address. */
1147 struct temp_slot
*q
;
1149 if (p
->level
== temp_slot_level
)
1151 for (q
= temp_slots
; q
; q
= q
->next
)
1152 if (q
!= p
&& q
->addr_taken
&& q
->level
== p
->level
)
1161 /* Otherwise, preserve all non-kept slots at this level. */
1162 for (p
= temp_slots
; p
; p
= p
->next
)
1163 if (p
->in_use
&& p
->level
== temp_slot_level
&& ! p
->keep
)
1167 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1168 with that RTL_EXPR, promote it into a temporary slot at the present
1169 level so it will not be freed when we free slots made in the
1173 preserve_rtl_expr_result (x
)
1176 struct temp_slot
*p
;
1178 /* If X is not in memory or is at a constant address, it cannot be in
1179 a temporary slot. */
1180 if (x
== 0 || GET_CODE (x
) != MEM
|| CONSTANT_P (XEXP (x
, 0)))
1183 /* If we can find a match, move it to our level unless it is already at
1185 p
= find_temp_slot_from_address (XEXP (x
, 0));
1188 p
->level
= MIN (p
->level
, temp_slot_level
);
1195 /* Free all temporaries used so far. This is normally called at the end
1196 of generating code for a statement. Don't free any temporaries
1197 currently in use for an RTL_EXPR that hasn't yet been emitted.
1198 We could eventually do better than this since it can be reused while
1199 generating the same RTL_EXPR, but this is complex and probably not
1205 struct temp_slot
*p
;
1207 for (p
= temp_slots
; p
; p
= p
->next
)
1208 if (p
->in_use
&& p
->level
== temp_slot_level
&& ! p
->keep
1209 && p
->rtl_expr
== 0)
1212 combine_temp_slots ();
1215 /* Free all temporary slots used in T, an RTL_EXPR node. */
1218 free_temps_for_rtl_expr (t
)
1221 struct temp_slot
*p
;
1223 for (p
= temp_slots
; p
; p
= p
->next
)
1224 if (p
->rtl_expr
== t
)
1227 combine_temp_slots ();
1230 /* Mark all temporaries ever allocated in this function as not suitable
1231 for reuse until the current level is exited. */
1234 mark_all_temps_used ()
1236 struct temp_slot
*p
;
1238 for (p
= temp_slots
; p
; p
= p
->next
)
1240 p
->in_use
= p
->keep
= 1;
1241 p
->level
= MIN (p
->level
, temp_slot_level
);
1245 /* Push deeper into the nesting level for stack temporaries. */
1253 /* Pop a temporary nesting level. All slots in use in the current level
1259 struct temp_slot
*p
;
1261 for (p
= temp_slots
; p
; p
= p
->next
)
1262 if (p
->in_use
&& p
->level
== temp_slot_level
&& p
->rtl_expr
== 0)
1265 combine_temp_slots ();
1270 /* Initialize temporary slots. */
1275 /* We have not allocated any temporaries yet. */
1277 temp_slot_level
= 0;
1278 target_temp_slot_level
= 0;
1281 /* Retroactively move an auto variable from a register to a stack slot.
1282 This is done when an address-reference to the variable is seen. */
1285 put_var_into_stack (decl
)
1289 enum machine_mode promoted_mode
, decl_mode
;
1290 struct function
*function
= 0;
1292 int can_use_addressof
;
1294 context
= decl_function_context (decl
);
1296 /* Get the current rtl used for this object and it's original mode. */
1297 reg
= TREE_CODE (decl
) == SAVE_EXPR
? SAVE_EXPR_RTL (decl
) : DECL_RTL (decl
);
1299 /* No need to do anything if decl has no rtx yet
1300 since in that case caller is setting TREE_ADDRESSABLE
1301 and a stack slot will be assigned when the rtl is made. */
1305 /* Get the declared mode for this object. */
1306 decl_mode
= (TREE_CODE (decl
) == SAVE_EXPR
? TYPE_MODE (TREE_TYPE (decl
))
1307 : DECL_MODE (decl
));
1308 /* Get the mode it's actually stored in. */
1309 promoted_mode
= GET_MODE (reg
);
1311 /* If this variable comes from an outer function,
1312 find that function's saved context. */
1313 if (context
!= current_function_decl
&& context
!= inline_function_decl
)
1314 for (function
= outer_function_chain
; function
; function
= function
->next
)
1315 if (function
->decl
== context
)
1318 /* If this is a variable-size object with a pseudo to address it,
1319 put that pseudo into the stack, if the var is nonlocal. */
1320 if (DECL_NONLOCAL (decl
)
1321 && GET_CODE (reg
) == MEM
1322 && GET_CODE (XEXP (reg
, 0)) == REG
1323 && REGNO (XEXP (reg
, 0)) > LAST_VIRTUAL_REGISTER
)
1325 reg
= XEXP (reg
, 0);
1326 decl_mode
= promoted_mode
= GET_MODE (reg
);
1331 /* FIXME make it work for promoted modes too */
1332 && decl_mode
== promoted_mode
1333 #ifdef NON_SAVING_SETJMP
1334 && ! (NON_SAVING_SETJMP
&& current_function_calls_setjmp
)
1338 /* If we can't use ADDRESSOF, make sure we see through one we already
1340 if (! can_use_addressof
&& GET_CODE (reg
) == MEM
1341 && GET_CODE (XEXP (reg
, 0)) == ADDRESSOF
)
1342 reg
= XEXP (XEXP (reg
, 0), 0);
1344 /* Now we should have a value that resides in one or more pseudo regs. */
1346 if (GET_CODE (reg
) == REG
)
1348 /* If this variable lives in the current function and we don't need
1349 to put things in the stack for the sake of setjmp, try to keep it
1350 in a register until we know we actually need the address. */
1351 if (can_use_addressof
)
1352 gen_mem_addressof (reg
, decl
);
1354 put_reg_into_stack (function
, reg
, TREE_TYPE (decl
),
1355 promoted_mode
, decl_mode
,
1356 TREE_SIDE_EFFECTS (decl
), 0);
1358 else if (GET_CODE (reg
) == CONCAT
)
1360 /* A CONCAT contains two pseudos; put them both in the stack.
1361 We do it so they end up consecutive. */
1362 enum machine_mode part_mode
= GET_MODE (XEXP (reg
, 0));
1363 tree part_type
= TREE_TYPE (TREE_TYPE (decl
));
1364 #ifdef FRAME_GROWS_DOWNWARD
1365 /* Since part 0 should have a lower address, do it second. */
1366 put_reg_into_stack (function
, XEXP (reg
, 1), part_type
, part_mode
,
1367 part_mode
, TREE_SIDE_EFFECTS (decl
), 0);
1368 put_reg_into_stack (function
, XEXP (reg
, 0), part_type
, part_mode
,
1369 part_mode
, TREE_SIDE_EFFECTS (decl
), 0);
1371 put_reg_into_stack (function
, XEXP (reg
, 0), part_type
, part_mode
,
1372 part_mode
, TREE_SIDE_EFFECTS (decl
), 0);
1373 put_reg_into_stack (function
, XEXP (reg
, 1), part_type
, part_mode
,
1374 part_mode
, TREE_SIDE_EFFECTS (decl
), 0);
1377 /* Change the CONCAT into a combined MEM for both parts. */
1378 PUT_CODE (reg
, MEM
);
1379 MEM_VOLATILE_P (reg
) = MEM_VOLATILE_P (XEXP (reg
, 0));
1381 /* The two parts are in memory order already.
1382 Use the lower parts address as ours. */
1383 XEXP (reg
, 0) = XEXP (XEXP (reg
, 0), 0);
1384 /* Prevent sharing of rtl that might lose. */
1385 if (GET_CODE (XEXP (reg
, 0)) == PLUS
)
1386 XEXP (reg
, 0) = copy_rtx (XEXP (reg
, 0));
1391 if (flag_check_memory_usage
)
1392 emit_library_call (chkr_set_right_libfunc
, 1, VOIDmode
, 3,
1393 XEXP (reg
, 0), ptr_mode
,
1394 GEN_INT (GET_MODE_SIZE (GET_MODE (reg
))),
1395 TYPE_MODE (sizetype
),
1396 GEN_INT (MEMORY_USE_RW
),
1397 TYPE_MODE (integer_type_node
));
1400 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1401 into the stack frame of FUNCTION (0 means the current function).
1402 DECL_MODE is the machine mode of the user-level data type.
1403 PROMOTED_MODE is the machine mode of the register.
1404 VOLATILE_P is nonzero if this is for a "volatile" decl. */
1407 put_reg_into_stack (function
, reg
, type
, promoted_mode
, decl_mode
, volatile_p
,
1409 struct function
*function
;
1412 enum machine_mode promoted_mode
, decl_mode
;
1417 int regno
= original_regno
;
1420 regno
= REGNO (reg
);
1424 if (regno
< function
->max_parm_reg
)
1425 new = function
->parm_reg_stack_loc
[regno
];
1427 new = assign_outer_stack_local (decl_mode
, GET_MODE_SIZE (decl_mode
),
1432 if (regno
< max_parm_reg
)
1433 new = parm_reg_stack_loc
[regno
];
1435 new = assign_stack_local (decl_mode
, GET_MODE_SIZE (decl_mode
), 0);
1438 PUT_MODE (reg
, decl_mode
);
1439 XEXP (reg
, 0) = XEXP (new, 0);
1440 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1441 MEM_VOLATILE_P (reg
) = volatile_p
;
1442 PUT_CODE (reg
, MEM
);
1444 /* If this is a memory ref that contains aggregate components,
1445 mark it as such for cse and loop optimize. If we are reusing a
1446 previously generated stack slot, then we need to copy the bit in
1447 case it was set for other reasons. For instance, it is set for
1448 __builtin_va_alist. */
1449 MEM_IN_STRUCT_P (reg
) = AGGREGATE_TYPE_P (type
) | MEM_IN_STRUCT_P (new);
1451 /* Now make sure that all refs to the variable, previously made
1452 when it was a register, are fixed up to be valid again. */
1455 struct var_refs_queue
*temp
;
1457 /* Variable is inherited; fix it up when we get back to its function. */
1458 push_obstacks (function
->function_obstack
,
1459 function
->function_maybepermanent_obstack
);
1461 /* See comment in restore_tree_status in tree.c for why this needs to be
1462 on saveable obstack. */
1464 = (struct var_refs_queue
*) savealloc (sizeof (struct var_refs_queue
));
1465 temp
->modified
= reg
;
1466 temp
->promoted_mode
= promoted_mode
;
1467 temp
->unsignedp
= TREE_UNSIGNED (type
);
1468 temp
->next
= function
->fixup_var_refs_queue
;
1469 function
->fixup_var_refs_queue
= temp
;
1473 /* Variable is local; fix it up now. */
1474 fixup_var_refs (reg
, promoted_mode
, TREE_UNSIGNED (type
));
1478 fixup_var_refs (var
, promoted_mode
, unsignedp
)
1480 enum machine_mode promoted_mode
;
1484 rtx first_insn
= get_insns ();
1485 struct sequence_stack
*stack
= sequence_stack
;
1486 tree rtl_exps
= rtl_expr_chain
;
1488 /* Must scan all insns for stack-refs that exceed the limit. */
1489 fixup_var_refs_insns (var
, promoted_mode
, unsignedp
, first_insn
, stack
== 0);
1491 /* Scan all pending sequences too. */
1492 for (; stack
; stack
= stack
->next
)
1494 push_to_sequence (stack
->first
);
1495 fixup_var_refs_insns (var
, promoted_mode
, unsignedp
,
1496 stack
->first
, stack
->next
!= 0);
1497 /* Update remembered end of sequence
1498 in case we added an insn at the end. */
1499 stack
->last
= get_last_insn ();
1503 /* Scan all waiting RTL_EXPRs too. */
1504 for (pending
= rtl_exps
; pending
; pending
= TREE_CHAIN (pending
))
1506 rtx seq
= RTL_EXPR_SEQUENCE (TREE_VALUE (pending
));
1507 if (seq
!= const0_rtx
&& seq
!= 0)
1509 push_to_sequence (seq
);
1510 fixup_var_refs_insns (var
, promoted_mode
, unsignedp
, seq
, 0);
1516 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1517 some part of an insn. Return a struct fixup_replacement whose OLD
1518 value is equal to X. Allocate a new structure if no such entry exists. */
1520 static struct fixup_replacement
*
1521 find_fixup_replacement (replacements
, x
)
1522 struct fixup_replacement
**replacements
;
1525 struct fixup_replacement
*p
;
1527 /* See if we have already replaced this. */
1528 for (p
= *replacements
; p
&& p
->old
!= x
; p
= p
->next
)
1533 p
= (struct fixup_replacement
*) oballoc (sizeof (struct fixup_replacement
));
1536 p
->next
= *replacements
;
1543 /* Scan the insn-chain starting with INSN for refs to VAR
1544 and fix them up. TOPLEVEL is nonzero if this chain is the
1545 main chain of insns for the current function. */
1548 fixup_var_refs_insns (var
, promoted_mode
, unsignedp
, insn
, toplevel
)
1550 enum machine_mode promoted_mode
;
1559 rtx next
= NEXT_INSN (insn
);
1561 if (GET_RTX_CLASS (GET_CODE (insn
)) == 'i')
1563 /* If this is a CLOBBER of VAR, delete it.
1565 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1566 and REG_RETVAL notes too. */
1567 if (GET_CODE (PATTERN (insn
)) == CLOBBER
1568 && XEXP (PATTERN (insn
), 0) == var
)
1570 if ((note
= find_reg_note (insn
, REG_LIBCALL
, NULL_RTX
)) != 0)
1571 /* The REG_LIBCALL note will go away since we are going to
1572 turn INSN into a NOTE, so just delete the
1573 corresponding REG_RETVAL note. */
1574 remove_note (XEXP (note
, 0),
1575 find_reg_note (XEXP (note
, 0), REG_RETVAL
,
1578 /* In unoptimized compilation, we shouldn't call delete_insn
1579 except in jump.c doing warnings. */
1580 PUT_CODE (insn
, NOTE
);
1581 NOTE_LINE_NUMBER (insn
) = NOTE_INSN_DELETED
;
1582 NOTE_SOURCE_FILE (insn
) = 0;
1585 /* The insn to load VAR from a home in the arglist
1586 is now a no-op. When we see it, just delete it. */
1588 && GET_CODE (PATTERN (insn
)) == SET
1589 && SET_DEST (PATTERN (insn
)) == var
1590 /* If this represents the result of an insn group,
1591 don't delete the insn. */
1592 && find_reg_note (insn
, REG_RETVAL
, NULL_RTX
) == 0
1593 && rtx_equal_p (SET_SRC (PATTERN (insn
)), var
))
1595 /* In unoptimized compilation, we shouldn't call delete_insn
1596 except in jump.c doing warnings. */
1597 PUT_CODE (insn
, NOTE
);
1598 NOTE_LINE_NUMBER (insn
) = NOTE_INSN_DELETED
;
1599 NOTE_SOURCE_FILE (insn
) = 0;
1600 if (insn
== last_parm_insn
)
1601 last_parm_insn
= PREV_INSN (next
);
1605 struct fixup_replacement
*replacements
= 0;
1606 rtx next_insn
= NEXT_INSN (insn
);
1608 if (SMALL_REGISTER_CLASSES
)
1610 /* If the insn that copies the results of a CALL_INSN
1611 into a pseudo now references VAR, we have to use an
1612 intermediate pseudo since we want the life of the
1613 return value register to be only a single insn.
1615 If we don't use an intermediate pseudo, such things as
1616 address computations to make the address of VAR valid
1617 if it is not can be placed between the CALL_INSN and INSN.
1619 To make sure this doesn't happen, we record the destination
1620 of the CALL_INSN and see if the next insn uses both that
1623 if (call_dest
!= 0 && GET_CODE (insn
) == INSN
1624 && reg_mentioned_p (var
, PATTERN (insn
))
1625 && reg_mentioned_p (call_dest
, PATTERN (insn
)))
1627 rtx temp
= gen_reg_rtx (GET_MODE (call_dest
));
1629 emit_insn_before (gen_move_insn (temp
, call_dest
), insn
);
1631 PATTERN (insn
) = replace_rtx (PATTERN (insn
),
1635 if (GET_CODE (insn
) == CALL_INSN
1636 && GET_CODE (PATTERN (insn
)) == SET
)
1637 call_dest
= SET_DEST (PATTERN (insn
));
1638 else if (GET_CODE (insn
) == CALL_INSN
1639 && GET_CODE (PATTERN (insn
)) == PARALLEL
1640 && GET_CODE (XVECEXP (PATTERN (insn
), 0, 0)) == SET
)
1641 call_dest
= SET_DEST (XVECEXP (PATTERN (insn
), 0, 0));
1646 /* See if we have to do anything to INSN now that VAR is in
1647 memory. If it needs to be loaded into a pseudo, use a single
1648 pseudo for the entire insn in case there is a MATCH_DUP
1649 between two operands. We pass a pointer to the head of
1650 a list of struct fixup_replacements. If fixup_var_refs_1
1651 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1652 it will record them in this list.
1654 If it allocated a pseudo for any replacement, we copy into
1657 fixup_var_refs_1 (var
, promoted_mode
, &PATTERN (insn
), insn
,
1660 /* If this is last_parm_insn, and any instructions were output
1661 after it to fix it up, then we must set last_parm_insn to
1662 the last such instruction emitted. */
1663 if (insn
== last_parm_insn
)
1664 last_parm_insn
= PREV_INSN (next_insn
);
1666 while (replacements
)
1668 if (GET_CODE (replacements
->new) == REG
)
1673 /* OLD might be a (subreg (mem)). */
1674 if (GET_CODE (replacements
->old
) == SUBREG
)
1676 = fixup_memory_subreg (replacements
->old
, insn
, 0);
1679 = fixup_stack_1 (replacements
->old
, insn
);
1681 insert_before
= insn
;
1683 /* If we are changing the mode, do a conversion.
1684 This might be wasteful, but combine.c will
1685 eliminate much of the waste. */
1687 if (GET_MODE (replacements
->new)
1688 != GET_MODE (replacements
->old
))
1691 convert_move (replacements
->new,
1692 replacements
->old
, unsignedp
);
1693 seq
= gen_sequence ();
1697 seq
= gen_move_insn (replacements
->new,
1700 emit_insn_before (seq
, insert_before
);
1703 replacements
= replacements
->next
;
1707 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1708 But don't touch other insns referred to by reg-notes;
1709 we will get them elsewhere. */
1710 for (note
= REG_NOTES (insn
); note
; note
= XEXP (note
, 1))
1711 if (GET_CODE (note
) != INSN_LIST
)
1713 = walk_fixup_memory_subreg (XEXP (note
, 0), insn
, 1);
1719 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1720 See if the rtx expression at *LOC in INSN needs to be changed.
1722 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1723 contain a list of original rtx's and replacements. If we find that we need
1724 to modify this insn by replacing a memory reference with a pseudo or by
1725 making a new MEM to implement a SUBREG, we consult that list to see if
1726 we have already chosen a replacement. If none has already been allocated,
1727 we allocate it and update the list. fixup_var_refs_insns will copy VAR
1728 or the SUBREG, as appropriate, to the pseudo. */
1731 fixup_var_refs_1 (var
, promoted_mode
, loc
, insn
, replacements
)
1733 enum machine_mode promoted_mode
;
1736 struct fixup_replacement
**replacements
;
1739 register rtx x
= *loc
;
1740 RTX_CODE code
= GET_CODE (x
);
1742 register rtx tem
, tem1
;
1743 struct fixup_replacement
*replacement
;
1748 if (XEXP (x
, 0) == var
)
1750 /* Prevent sharing of rtl that might lose. */
1751 rtx sub
= copy_rtx (XEXP (var
, 0));
1755 if (! validate_change (insn
, loc
, sub
, 0))
1757 rtx y
= force_operand (sub
, NULL_RTX
);
1759 if (! validate_change (insn
, loc
, y
, 0))
1760 *loc
= copy_to_reg (y
);
1763 emit_insn_before (gen_sequence (), insn
);
1771 /* If we already have a replacement, use it. Otherwise,
1772 try to fix up this address in case it is invalid. */
1774 replacement
= find_fixup_replacement (replacements
, var
);
1775 if (replacement
->new)
1777 *loc
= replacement
->new;
1781 *loc
= replacement
->new = x
= fixup_stack_1 (x
, insn
);
1783 /* Unless we are forcing memory to register or we changed the mode,
1784 we can leave things the way they are if the insn is valid. */
1786 INSN_CODE (insn
) = -1;
1787 if (! flag_force_mem
&& GET_MODE (x
) == promoted_mode
1788 && recog_memoized (insn
) >= 0)
1791 *loc
= replacement
->new = gen_reg_rtx (promoted_mode
);
1795 /* If X contains VAR, we need to unshare it here so that we update
1796 each occurrence separately. But all identical MEMs in one insn
1797 must be replaced with the same rtx because of the possibility of
1800 if (reg_mentioned_p (var
, x
))
1802 replacement
= find_fixup_replacement (replacements
, x
);
1803 if (replacement
->new == 0)
1804 replacement
->new = copy_most_rtx (x
, var
);
1806 *loc
= x
= replacement
->new;
1822 /* Note that in some cases those types of expressions are altered
1823 by optimize_bit_field, and do not survive to get here. */
1824 if (XEXP (x
, 0) == var
1825 || (GET_CODE (XEXP (x
, 0)) == SUBREG
1826 && SUBREG_REG (XEXP (x
, 0)) == var
))
1828 /* Get TEM as a valid MEM in the mode presently in the insn.
1830 We don't worry about the possibility of MATCH_DUP here; it
1831 is highly unlikely and would be tricky to handle. */
1834 if (GET_CODE (tem
) == SUBREG
)
1836 if (GET_MODE_BITSIZE (GET_MODE (tem
))
1837 > GET_MODE_BITSIZE (GET_MODE (var
)))
1839 replacement
= find_fixup_replacement (replacements
, var
);
1840 if (replacement
->new == 0)
1841 replacement
->new = gen_reg_rtx (GET_MODE (var
));
1842 SUBREG_REG (tem
) = replacement
->new;
1845 tem
= fixup_memory_subreg (tem
, insn
, 0);
1848 tem
= fixup_stack_1 (tem
, insn
);
1850 /* Unless we want to load from memory, get TEM into the proper mode
1851 for an extract from memory. This can only be done if the
1852 extract is at a constant position and length. */
1854 if (! flag_force_mem
&& GET_CODE (XEXP (x
, 1)) == CONST_INT
1855 && GET_CODE (XEXP (x
, 2)) == CONST_INT
1856 && ! mode_dependent_address_p (XEXP (tem
, 0))
1857 && ! MEM_VOLATILE_P (tem
))
1859 enum machine_mode wanted_mode
= VOIDmode
;
1860 enum machine_mode is_mode
= GET_MODE (tem
);
1861 int pos
= INTVAL (XEXP (x
, 2));
1864 if (GET_CODE (x
) == ZERO_EXTRACT
)
1865 wanted_mode
= insn_operand_mode
[(int) CODE_FOR_extzv
][1];
1868 if (GET_CODE (x
) == SIGN_EXTRACT
)
1869 wanted_mode
= insn_operand_mode
[(int) CODE_FOR_extv
][1];
1871 /* If we have a narrower mode, we can do something. */
1872 if (wanted_mode
!= VOIDmode
1873 && GET_MODE_SIZE (wanted_mode
) < GET_MODE_SIZE (is_mode
))
1875 int offset
= pos
/ BITS_PER_UNIT
;
1876 rtx old_pos
= XEXP (x
, 2);
1879 /* If the bytes and bits are counted differently, we
1880 must adjust the offset. */
1881 if (BYTES_BIG_ENDIAN
!= BITS_BIG_ENDIAN
)
1882 offset
= (GET_MODE_SIZE (is_mode
)
1883 - GET_MODE_SIZE (wanted_mode
) - offset
);
1885 pos
%= GET_MODE_BITSIZE (wanted_mode
);
1887 newmem
= gen_rtx_MEM (wanted_mode
,
1888 plus_constant (XEXP (tem
, 0), offset
));
1889 RTX_UNCHANGING_P (newmem
) = RTX_UNCHANGING_P (tem
);
1890 MEM_VOLATILE_P (newmem
) = MEM_VOLATILE_P (tem
);
1891 MEM_IN_STRUCT_P (newmem
) = MEM_IN_STRUCT_P (tem
);
1893 /* Make the change and see if the insn remains valid. */
1894 INSN_CODE (insn
) = -1;
1895 XEXP (x
, 0) = newmem
;
1896 XEXP (x
, 2) = GEN_INT (pos
);
1898 if (recog_memoized (insn
) >= 0)
1901 /* Otherwise, restore old position. XEXP (x, 0) will be
1903 XEXP (x
, 2) = old_pos
;
1907 /* If we get here, the bitfield extract insn can't accept a memory
1908 reference. Copy the input into a register. */
1910 tem1
= gen_reg_rtx (GET_MODE (tem
));
1911 emit_insn_before (gen_move_insn (tem1
, tem
), insn
);
1918 if (SUBREG_REG (x
) == var
)
1920 /* If this is a special SUBREG made because VAR was promoted
1921 from a wider mode, replace it with VAR and call ourself
1922 recursively, this time saying that the object previously
1923 had its current mode (by virtue of the SUBREG). */
1925 if (SUBREG_PROMOTED_VAR_P (x
))
1928 fixup_var_refs_1 (var
, GET_MODE (var
), loc
, insn
, replacements
);
1932 /* If this SUBREG makes VAR wider, it has become a paradoxical
1933 SUBREG with VAR in memory, but these aren't allowed at this
1934 stage of the compilation. So load VAR into a pseudo and take
1935 a SUBREG of that pseudo. */
1936 if (GET_MODE_SIZE (GET_MODE (x
)) > GET_MODE_SIZE (GET_MODE (var
)))
1938 replacement
= find_fixup_replacement (replacements
, var
);
1939 if (replacement
->new == 0)
1940 replacement
->new = gen_reg_rtx (GET_MODE (var
));
1941 SUBREG_REG (x
) = replacement
->new;
1945 /* See if we have already found a replacement for this SUBREG.
1946 If so, use it. Otherwise, make a MEM and see if the insn
1947 is recognized. If not, or if we should force MEM into a register,
1948 make a pseudo for this SUBREG. */
1949 replacement
= find_fixup_replacement (replacements
, x
);
1950 if (replacement
->new)
1952 *loc
= replacement
->new;
1956 replacement
->new = *loc
= fixup_memory_subreg (x
, insn
, 0);
1958 INSN_CODE (insn
) = -1;
1959 if (! flag_force_mem
&& recog_memoized (insn
) >= 0)
1962 *loc
= replacement
->new = gen_reg_rtx (GET_MODE (x
));
1968 /* First do special simplification of bit-field references. */
1969 if (GET_CODE (SET_DEST (x
)) == SIGN_EXTRACT
1970 || GET_CODE (SET_DEST (x
)) == ZERO_EXTRACT
)
1971 optimize_bit_field (x
, insn
, 0);
1972 if (GET_CODE (SET_SRC (x
)) == SIGN_EXTRACT
1973 || GET_CODE (SET_SRC (x
)) == ZERO_EXTRACT
)
1974 optimize_bit_field (x
, insn
, NULL_PTR
);
1976 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
1977 into a register and then store it back out. */
1978 if (GET_CODE (SET_DEST (x
)) == ZERO_EXTRACT
1979 && GET_CODE (XEXP (SET_DEST (x
), 0)) == SUBREG
1980 && SUBREG_REG (XEXP (SET_DEST (x
), 0)) == var
1981 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x
), 0)))
1982 > GET_MODE_SIZE (GET_MODE (var
))))
1984 replacement
= find_fixup_replacement (replacements
, var
);
1985 if (replacement
->new == 0)
1986 replacement
->new = gen_reg_rtx (GET_MODE (var
));
1988 SUBREG_REG (XEXP (SET_DEST (x
), 0)) = replacement
->new;
1989 emit_insn_after (gen_move_insn (var
, replacement
->new), insn
);
1992 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
1993 insn into a pseudo and store the low part of the pseudo into VAR. */
1994 if (GET_CODE (SET_DEST (x
)) == SUBREG
1995 && SUBREG_REG (SET_DEST (x
)) == var
1996 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x
)))
1997 > GET_MODE_SIZE (GET_MODE (var
))))
1999 SET_DEST (x
) = tem
= gen_reg_rtx (GET_MODE (SET_DEST (x
)));
2000 emit_insn_after (gen_move_insn (var
, gen_lowpart (GET_MODE (var
),
2007 rtx dest
= SET_DEST (x
);
2008 rtx src
= SET_SRC (x
);
2010 rtx outerdest
= dest
;
2013 while (GET_CODE (dest
) == SUBREG
|| GET_CODE (dest
) == STRICT_LOW_PART
2014 || GET_CODE (dest
) == SIGN_EXTRACT
2015 || GET_CODE (dest
) == ZERO_EXTRACT
)
2016 dest
= XEXP (dest
, 0);
2018 if (GET_CODE (src
) == SUBREG
)
2019 src
= XEXP (src
, 0);
2021 /* If VAR does not appear at the top level of the SET
2022 just scan the lower levels of the tree. */
2024 if (src
!= var
&& dest
!= var
)
2027 /* We will need to rerecognize this insn. */
2028 INSN_CODE (insn
) = -1;
2031 if (GET_CODE (outerdest
) == ZERO_EXTRACT
&& dest
== var
)
2033 /* Since this case will return, ensure we fixup all the
2035 fixup_var_refs_1 (var
, promoted_mode
, &XEXP (outerdest
, 1),
2036 insn
, replacements
);
2037 fixup_var_refs_1 (var
, promoted_mode
, &XEXP (outerdest
, 2),
2038 insn
, replacements
);
2039 fixup_var_refs_1 (var
, promoted_mode
, &SET_SRC (x
),
2040 insn
, replacements
);
2042 tem
= XEXP (outerdest
, 0);
2044 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2045 that may appear inside a ZERO_EXTRACT.
2046 This was legitimate when the MEM was a REG. */
2047 if (GET_CODE (tem
) == SUBREG
2048 && SUBREG_REG (tem
) == var
)
2049 tem
= fixup_memory_subreg (tem
, insn
, 0);
2051 tem
= fixup_stack_1 (tem
, insn
);
2053 if (GET_CODE (XEXP (outerdest
, 1)) == CONST_INT
2054 && GET_CODE (XEXP (outerdest
, 2)) == CONST_INT
2055 && ! mode_dependent_address_p (XEXP (tem
, 0))
2056 && ! MEM_VOLATILE_P (tem
))
2058 enum machine_mode wanted_mode
2059 = insn_operand_mode
[(int) CODE_FOR_insv
][0];
2060 enum machine_mode is_mode
= GET_MODE (tem
);
2061 int pos
= INTVAL (XEXP (outerdest
, 2));
2063 /* If we have a narrower mode, we can do something. */
2064 if (GET_MODE_SIZE (wanted_mode
) < GET_MODE_SIZE (is_mode
))
2066 int offset
= pos
/ BITS_PER_UNIT
;
2067 rtx old_pos
= XEXP (outerdest
, 2);
2070 if (BYTES_BIG_ENDIAN
!= BITS_BIG_ENDIAN
)
2071 offset
= (GET_MODE_SIZE (is_mode
)
2072 - GET_MODE_SIZE (wanted_mode
) - offset
);
2074 pos
%= GET_MODE_BITSIZE (wanted_mode
);
2076 newmem
= gen_rtx_MEM (wanted_mode
,
2077 plus_constant (XEXP (tem
, 0), offset
));
2078 RTX_UNCHANGING_P (newmem
) = RTX_UNCHANGING_P (tem
);
2079 MEM_VOLATILE_P (newmem
) = MEM_VOLATILE_P (tem
);
2080 MEM_IN_STRUCT_P (newmem
) = MEM_IN_STRUCT_P (tem
);
2082 /* Make the change and see if the insn remains valid. */
2083 INSN_CODE (insn
) = -1;
2084 XEXP (outerdest
, 0) = newmem
;
2085 XEXP (outerdest
, 2) = GEN_INT (pos
);
2087 if (recog_memoized (insn
) >= 0)
2090 /* Otherwise, restore old position. XEXP (x, 0) will be
2092 XEXP (outerdest
, 2) = old_pos
;
2096 /* If we get here, the bit-field store doesn't allow memory
2097 or isn't located at a constant position. Load the value into
2098 a register, do the store, and put it back into memory. */
2100 tem1
= gen_reg_rtx (GET_MODE (tem
));
2101 emit_insn_before (gen_move_insn (tem1
, tem
), insn
);
2102 emit_insn_after (gen_move_insn (tem
, tem1
), insn
);
2103 XEXP (outerdest
, 0) = tem1
;
2108 /* STRICT_LOW_PART is a no-op on memory references
2109 and it can cause combinations to be unrecognizable,
2112 if (dest
== var
&& GET_CODE (SET_DEST (x
)) == STRICT_LOW_PART
)
2113 SET_DEST (x
) = XEXP (SET_DEST (x
), 0);
2115 /* A valid insn to copy VAR into or out of a register
2116 must be left alone, to avoid an infinite loop here.
2117 If the reference to VAR is by a subreg, fix that up,
2118 since SUBREG is not valid for a memref.
2119 Also fix up the address of the stack slot.
2121 Note that we must not try to recognize the insn until
2122 after we know that we have valid addresses and no
2123 (subreg (mem ...) ...) constructs, since these interfere
2124 with determining the validity of the insn. */
2126 if ((SET_SRC (x
) == var
2127 || (GET_CODE (SET_SRC (x
)) == SUBREG
2128 && SUBREG_REG (SET_SRC (x
)) == var
))
2129 && (GET_CODE (SET_DEST (x
)) == REG
2130 || (GET_CODE (SET_DEST (x
)) == SUBREG
2131 && GET_CODE (SUBREG_REG (SET_DEST (x
))) == REG
))
2132 && GET_MODE (var
) == promoted_mode
2133 && x
== single_set (insn
))
2137 replacement
= find_fixup_replacement (replacements
, SET_SRC (x
));
2138 if (replacement
->new)
2139 SET_SRC (x
) = replacement
->new;
2140 else if (GET_CODE (SET_SRC (x
)) == SUBREG
)
2141 SET_SRC (x
) = replacement
->new
2142 = fixup_memory_subreg (SET_SRC (x
), insn
, 0);
2144 SET_SRC (x
) = replacement
->new
2145 = fixup_stack_1 (SET_SRC (x
), insn
);
2147 if (recog_memoized (insn
) >= 0)
2150 /* INSN is not valid, but we know that we want to
2151 copy SET_SRC (x) to SET_DEST (x) in some way. So
2152 we generate the move and see whether it requires more
2153 than one insn. If it does, we emit those insns and
2154 delete INSN. Otherwise, we an just replace the pattern
2155 of INSN; we have already verified above that INSN has
2156 no other function that to do X. */
2158 pat
= gen_move_insn (SET_DEST (x
), SET_SRC (x
));
2159 if (GET_CODE (pat
) == SEQUENCE
)
2161 emit_insn_after (pat
, insn
);
2162 PUT_CODE (insn
, NOTE
);
2163 NOTE_LINE_NUMBER (insn
) = NOTE_INSN_DELETED
;
2164 NOTE_SOURCE_FILE (insn
) = 0;
2167 PATTERN (insn
) = pat
;
2172 if ((SET_DEST (x
) == var
2173 || (GET_CODE (SET_DEST (x
)) == SUBREG
2174 && SUBREG_REG (SET_DEST (x
)) == var
))
2175 && (GET_CODE (SET_SRC (x
)) == REG
2176 || (GET_CODE (SET_SRC (x
)) == SUBREG
2177 && GET_CODE (SUBREG_REG (SET_SRC (x
))) == REG
))
2178 && GET_MODE (var
) == promoted_mode
2179 && x
== single_set (insn
))
2183 if (GET_CODE (SET_DEST (x
)) == SUBREG
)
2184 SET_DEST (x
) = fixup_memory_subreg (SET_DEST (x
), insn
, 0);
2186 SET_DEST (x
) = fixup_stack_1 (SET_DEST (x
), insn
);
2188 if (recog_memoized (insn
) >= 0)
2191 pat
= gen_move_insn (SET_DEST (x
), SET_SRC (x
));
2192 if (GET_CODE (pat
) == SEQUENCE
)
2194 emit_insn_after (pat
, insn
);
2195 PUT_CODE (insn
, NOTE
);
2196 NOTE_LINE_NUMBER (insn
) = NOTE_INSN_DELETED
;
2197 NOTE_SOURCE_FILE (insn
) = 0;
2200 PATTERN (insn
) = pat
;
2205 /* Otherwise, storing into VAR must be handled specially
2206 by storing into a temporary and copying that into VAR
2207 with a new insn after this one. Note that this case
2208 will be used when storing into a promoted scalar since
2209 the insn will now have different modes on the input
2210 and output and hence will be invalid (except for the case
2211 of setting it to a constant, which does not need any
2212 change if it is valid). We generate extra code in that case,
2213 but combine.c will eliminate it. */
2218 rtx fixeddest
= SET_DEST (x
);
2220 /* STRICT_LOW_PART can be discarded, around a MEM. */
2221 if (GET_CODE (fixeddest
) == STRICT_LOW_PART
)
2222 fixeddest
= XEXP (fixeddest
, 0);
2223 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2224 if (GET_CODE (fixeddest
) == SUBREG
)
2226 fixeddest
= fixup_memory_subreg (fixeddest
, insn
, 0);
2227 promoted_mode
= GET_MODE (fixeddest
);
2230 fixeddest
= fixup_stack_1 (fixeddest
, insn
);
2232 temp
= gen_reg_rtx (promoted_mode
);
2234 emit_insn_after (gen_move_insn (fixeddest
,
2235 gen_lowpart (GET_MODE (fixeddest
),
2239 SET_DEST (x
) = temp
;
2247 /* Nothing special about this RTX; fix its operands. */
2249 fmt
= GET_RTX_FORMAT (code
);
2250 for (i
= GET_RTX_LENGTH (code
) - 1; i
>= 0; i
--)
2253 fixup_var_refs_1 (var
, promoted_mode
, &XEXP (x
, i
), insn
, replacements
);
2257 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
2258 fixup_var_refs_1 (var
, promoted_mode
, &XVECEXP (x
, i
, j
),
2259 insn
, replacements
);
2264 /* Given X, an rtx of the form (SUBREG:m1 (MEM:m2 addr)),
2265 return an rtx (MEM:m1 newaddr) which is equivalent.
2266 If any insns must be emitted to compute NEWADDR, put them before INSN.
2268 UNCRITICAL nonzero means accept paradoxical subregs.
2269 This is used for subregs found inside REG_NOTES. */
2272 fixup_memory_subreg (x
, insn
, uncritical
)
2277 int offset
= SUBREG_WORD (x
) * UNITS_PER_WORD
;
2278 rtx addr
= XEXP (SUBREG_REG (x
), 0);
2279 enum machine_mode mode
= GET_MODE (x
);
2282 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2283 if (GET_MODE_SIZE (mode
) > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x
)))
2287 if (BYTES_BIG_ENDIAN
)
2288 offset
+= (MIN (UNITS_PER_WORD
, GET_MODE_SIZE (GET_MODE (SUBREG_REG (x
))))
2289 - MIN (UNITS_PER_WORD
, GET_MODE_SIZE (mode
)));
2290 addr
= plus_constant (addr
, offset
);
2291 if (!flag_force_addr
&& memory_address_p (mode
, addr
))
2292 /* Shortcut if no insns need be emitted. */
2293 return change_address (SUBREG_REG (x
), mode
, addr
);
2295 result
= change_address (SUBREG_REG (x
), mode
, addr
);
2296 emit_insn_before (gen_sequence (), insn
);
2301 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2302 Replace subexpressions of X in place.
2303 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2304 Otherwise return X, with its contents possibly altered.
2306 If any insns must be emitted to compute NEWADDR, put them before INSN.
2308 UNCRITICAL is as in fixup_memory_subreg. */
2311 walk_fixup_memory_subreg (x
, insn
, uncritical
)
2316 register enum rtx_code code
;
2323 code
= GET_CODE (x
);
2325 if (code
== SUBREG
&& GET_CODE (SUBREG_REG (x
)) == MEM
)
2326 return fixup_memory_subreg (x
, insn
, uncritical
);
2328 /* Nothing special about this RTX; fix its operands. */
2330 fmt
= GET_RTX_FORMAT (code
);
2331 for (i
= GET_RTX_LENGTH (code
) - 1; i
>= 0; i
--)
2334 XEXP (x
, i
) = walk_fixup_memory_subreg (XEXP (x
, i
), insn
, uncritical
);
2338 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
2340 = walk_fixup_memory_subreg (XVECEXP (x
, i
, j
), insn
, uncritical
);
2346 /* For each memory ref within X, if it refers to a stack slot
2347 with an out of range displacement, put the address in a temp register
2348 (emitting new insns before INSN to load these registers)
2349 and alter the memory ref to use that register.
2350 Replace each such MEM rtx with a copy, to avoid clobberage. */
2353 fixup_stack_1 (x
, insn
)
2358 register RTX_CODE code
= GET_CODE (x
);
2363 register rtx ad
= XEXP (x
, 0);
2364 /* If we have address of a stack slot but it's not valid
2365 (displacement is too large), compute the sum in a register. */
2366 if (GET_CODE (ad
) == PLUS
2367 && GET_CODE (XEXP (ad
, 0)) == REG
2368 && ((REGNO (XEXP (ad
, 0)) >= FIRST_VIRTUAL_REGISTER
2369 && REGNO (XEXP (ad
, 0)) <= LAST_VIRTUAL_REGISTER
)
2370 || REGNO (XEXP (ad
, 0)) == FRAME_POINTER_REGNUM
2371 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2372 || REGNO (XEXP (ad
, 0)) == HARD_FRAME_POINTER_REGNUM
2374 || REGNO (XEXP (ad
, 0)) == STACK_POINTER_REGNUM
2375 || REGNO (XEXP (ad
, 0)) == ARG_POINTER_REGNUM
2376 || XEXP (ad
, 0) == current_function_internal_arg_pointer
)
2377 && GET_CODE (XEXP (ad
, 1)) == CONST_INT
)
2380 if (memory_address_p (GET_MODE (x
), ad
))
2384 temp
= copy_to_reg (ad
);
2385 seq
= gen_sequence ();
2387 emit_insn_before (seq
, insn
);
2388 return change_address (x
, VOIDmode
, temp
);
2393 fmt
= GET_RTX_FORMAT (code
);
2394 for (i
= GET_RTX_LENGTH (code
) - 1; i
>= 0; i
--)
2397 XEXP (x
, i
) = fixup_stack_1 (XEXP (x
, i
), insn
);
2401 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
2402 XVECEXP (x
, i
, j
) = fixup_stack_1 (XVECEXP (x
, i
, j
), insn
);
2408 /* Optimization: a bit-field instruction whose field
2409 happens to be a byte or halfword in memory
2410 can be changed to a move instruction.
2412 We call here when INSN is an insn to examine or store into a bit-field.
2413 BODY is the SET-rtx to be altered.
2415 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2416 (Currently this is called only from function.c, and EQUIV_MEM
2420 optimize_bit_field (body
, insn
, equiv_mem
)
2425 register rtx bitfield
;
2428 enum machine_mode mode
;
2430 if (GET_CODE (SET_DEST (body
)) == SIGN_EXTRACT
2431 || GET_CODE (SET_DEST (body
)) == ZERO_EXTRACT
)
2432 bitfield
= SET_DEST (body
), destflag
= 1;
2434 bitfield
= SET_SRC (body
), destflag
= 0;
2436 /* First check that the field being stored has constant size and position
2437 and is in fact a byte or halfword suitably aligned. */
2439 if (GET_CODE (XEXP (bitfield
, 1)) == CONST_INT
2440 && GET_CODE (XEXP (bitfield
, 2)) == CONST_INT
2441 && ((mode
= mode_for_size (INTVAL (XEXP (bitfield
, 1)), MODE_INT
, 1))
2443 && INTVAL (XEXP (bitfield
, 2)) % INTVAL (XEXP (bitfield
, 1)) == 0)
2445 register rtx memref
= 0;
2447 /* Now check that the containing word is memory, not a register,
2448 and that it is safe to change the machine mode. */
2450 if (GET_CODE (XEXP (bitfield
, 0)) == MEM
)
2451 memref
= XEXP (bitfield
, 0);
2452 else if (GET_CODE (XEXP (bitfield
, 0)) == REG
2454 memref
= equiv_mem
[REGNO (XEXP (bitfield
, 0))];
2455 else if (GET_CODE (XEXP (bitfield
, 0)) == SUBREG
2456 && GET_CODE (SUBREG_REG (XEXP (bitfield
, 0))) == MEM
)
2457 memref
= SUBREG_REG (XEXP (bitfield
, 0));
2458 else if (GET_CODE (XEXP (bitfield
, 0)) == SUBREG
2460 && GET_CODE (SUBREG_REG (XEXP (bitfield
, 0))) == REG
)
2461 memref
= equiv_mem
[REGNO (SUBREG_REG (XEXP (bitfield
, 0)))];
2464 && ! mode_dependent_address_p (XEXP (memref
, 0))
2465 && ! MEM_VOLATILE_P (memref
))
2467 /* Now adjust the address, first for any subreg'ing
2468 that we are now getting rid of,
2469 and then for which byte of the word is wanted. */
2471 register int offset
= INTVAL (XEXP (bitfield
, 2));
2474 /* Adjust OFFSET to count bits from low-address byte. */
2475 if (BITS_BIG_ENDIAN
!= BYTES_BIG_ENDIAN
)
2476 offset
= (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield
, 0)))
2477 - offset
- INTVAL (XEXP (bitfield
, 1)));
2479 /* Adjust OFFSET to count bytes from low-address byte. */
2480 offset
/= BITS_PER_UNIT
;
2481 if (GET_CODE (XEXP (bitfield
, 0)) == SUBREG
)
2483 offset
+= SUBREG_WORD (XEXP (bitfield
, 0)) * UNITS_PER_WORD
;
2484 if (BYTES_BIG_ENDIAN
)
2485 offset
-= (MIN (UNITS_PER_WORD
,
2486 GET_MODE_SIZE (GET_MODE (XEXP (bitfield
, 0))))
2487 - MIN (UNITS_PER_WORD
,
2488 GET_MODE_SIZE (GET_MODE (memref
))));
2492 memref
= change_address (memref
, mode
,
2493 plus_constant (XEXP (memref
, 0), offset
));
2494 insns
= get_insns ();
2496 emit_insns_before (insns
, insn
);
2498 /* Store this memory reference where
2499 we found the bit field reference. */
2503 validate_change (insn
, &SET_DEST (body
), memref
, 1);
2504 if (! CONSTANT_ADDRESS_P (SET_SRC (body
)))
2506 rtx src
= SET_SRC (body
);
2507 while (GET_CODE (src
) == SUBREG
2508 && SUBREG_WORD (src
) == 0)
2509 src
= SUBREG_REG (src
);
2510 if (GET_MODE (src
) != GET_MODE (memref
))
2511 src
= gen_lowpart (GET_MODE (memref
), SET_SRC (body
));
2512 validate_change (insn
, &SET_SRC (body
), src
, 1);
2514 else if (GET_MODE (SET_SRC (body
)) != VOIDmode
2515 && GET_MODE (SET_SRC (body
)) != GET_MODE (memref
))
2516 /* This shouldn't happen because anything that didn't have
2517 one of these modes should have got converted explicitly
2518 and then referenced through a subreg.
2519 This is so because the original bit-field was
2520 handled by agg_mode and so its tree structure had
2521 the same mode that memref now has. */
2526 rtx dest
= SET_DEST (body
);
2528 while (GET_CODE (dest
) == SUBREG
2529 && SUBREG_WORD (dest
) == 0
2530 && (GET_MODE_CLASS (GET_MODE (dest
))
2531 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest
)))))
2532 dest
= SUBREG_REG (dest
);
2534 validate_change (insn
, &SET_DEST (body
), dest
, 1);
2536 if (GET_MODE (dest
) == GET_MODE (memref
))
2537 validate_change (insn
, &SET_SRC (body
), memref
, 1);
2540 /* Convert the mem ref to the destination mode. */
2541 rtx newreg
= gen_reg_rtx (GET_MODE (dest
));
2544 convert_move (newreg
, memref
,
2545 GET_CODE (SET_SRC (body
)) == ZERO_EXTRACT
);
2549 validate_change (insn
, &SET_SRC (body
), newreg
, 1);
2553 /* See if we can convert this extraction or insertion into
2554 a simple move insn. We might not be able to do so if this
2555 was, for example, part of a PARALLEL.
2557 If we succeed, write out any needed conversions. If we fail,
2558 it is hard to guess why we failed, so don't do anything
2559 special; just let the optimization be suppressed. */
2561 if (apply_change_group () && seq
)
2562 emit_insns_before (seq
, insn
);
2567 /* These routines are responsible for converting virtual register references
2568 to the actual hard register references once RTL generation is complete.
2570 The following four variables are used for communication between the
2571 routines. They contain the offsets of the virtual registers from their
2572 respective hard registers. */
2574 static int in_arg_offset
;
2575 static int var_offset
;
2576 static int dynamic_offset
;
2577 static int out_arg_offset
;
2579 /* In most machines, the stack pointer register is equivalent to the bottom
2582 #ifndef STACK_POINTER_OFFSET
2583 #define STACK_POINTER_OFFSET 0
2586 /* If not defined, pick an appropriate default for the offset of dynamically
2587 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2588 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2590 #ifndef STACK_DYNAMIC_OFFSET
2592 #ifdef ACCUMULATE_OUTGOING_ARGS
2593 /* The bottom of the stack points to the actual arguments. If
2594 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2595 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2596 stack space for register parameters is not pushed by the caller, but
2597 rather part of the fixed stack areas and hence not included in
2598 `current_function_outgoing_args_size'. Nevertheless, we must allow
2599 for it when allocating stack dynamic objects. */
2601 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2602 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2603 (current_function_outgoing_args_size \
2604 + REG_PARM_STACK_SPACE (FNDECL) + (STACK_POINTER_OFFSET))
2607 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2608 (current_function_outgoing_args_size + (STACK_POINTER_OFFSET))
2612 #define STACK_DYNAMIC_OFFSET(FNDECL) STACK_POINTER_OFFSET
2616 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just had
2617 its address taken. DECL is the decl for the object stored in the
2618 register, for later use if we do need to force REG into the stack.
2619 REG is overwritten by the MEM like in put_reg_into_stack. */
2622 gen_mem_addressof (reg
, decl
)
2626 tree type
= TREE_TYPE (decl
);
2628 rtx r
= gen_rtx_ADDRESSOF (Pmode
, gen_reg_rtx (GET_MODE (reg
)), REGNO (reg
));
2629 SET_ADDRESSOF_DECL (r
, decl
);
2632 PUT_CODE (reg
, MEM
);
2633 PUT_MODE (reg
, DECL_MODE (decl
));
2634 MEM_VOLATILE_P (reg
) = TREE_SIDE_EFFECTS (decl
);
2635 MEM_IN_STRUCT_P (reg
) = AGGREGATE_TYPE_P (type
);
2637 fixup_var_refs (reg
, GET_MODE (reg
), TREE_UNSIGNED (type
));
2641 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2644 flush_addressof (decl
)
2647 if ((TREE_CODE (decl
) == PARM_DECL
|| TREE_CODE (decl
) == VAR_DECL
)
2648 && DECL_RTL (decl
) != 0
2649 && GET_CODE (DECL_RTL (decl
)) == MEM
2650 && GET_CODE (XEXP (DECL_RTL (decl
), 0)) == ADDRESSOF
2651 && GET_CODE (XEXP (XEXP (DECL_RTL (decl
), 0), 0)) == REG
)
2652 put_addressof_into_stack (XEXP (DECL_RTL (decl
), 0));
2655 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2658 put_addressof_into_stack (r
)
2661 tree decl
= ADDRESSOF_DECL (r
);
2662 rtx reg
= XEXP (r
, 0);
2664 if (GET_CODE (reg
) != REG
)
2667 put_reg_into_stack (0, reg
, TREE_TYPE (decl
), GET_MODE (reg
),
2668 DECL_MODE (decl
), TREE_SIDE_EFFECTS (decl
),
2669 ADDRESSOF_REGNO (r
));
2672 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2673 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2677 purge_addressof_1 (loc
, insn
, force
)
2687 /* Re-start here to avoid recursion in common cases. */
2694 code
= GET_CODE (x
);
2696 if (code
== ADDRESSOF
&& GET_CODE (XEXP (x
, 0)) == MEM
)
2699 /* We must create a copy of the rtx because it was created by
2700 overwriting a REG rtx which is always shared. */
2701 rtx sub
= copy_rtx (XEXP (XEXP (x
, 0), 0));
2703 if (validate_change (insn
, loc
, sub
, 0))
2707 if (! validate_change (insn
, loc
,
2708 force_operand (sub
, NULL_RTX
),
2712 insns
= get_insns ();
2714 emit_insns_before (insns
, insn
);
2717 else if (code
== MEM
&& GET_CODE (XEXP (x
, 0)) == ADDRESSOF
&& ! force
)
2719 rtx sub
= XEXP (XEXP (x
, 0), 0);
2720 if (GET_CODE (sub
) == MEM
)
2721 sub
= gen_rtx_MEM (GET_MODE (x
), copy_rtx (XEXP (sub
, 0)));
2722 if (GET_CODE (sub
) == REG
&& GET_MODE (x
) != GET_MODE (sub
))
2724 if (! BYTES_BIG_ENDIAN
&& ! WORDS_BIG_ENDIAN
)
2726 rtx sub2
= gen_rtx_SUBREG (GET_MODE (x
), sub
, 0);
2727 if (validate_change (insn
, loc
, sub2
, 0))
2731 else if (validate_change (insn
, loc
, sub
, 0))
2733 /* else give up and put it into the stack */
2735 else if (code
== ADDRESSOF
)
2737 put_addressof_into_stack (x
);
2741 /* Scan all subexpressions. */
2742 fmt
= GET_RTX_FORMAT (code
);
2743 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
2746 purge_addressof_1 (&XEXP (x
, i
), insn
, force
);
2747 else if (*fmt
== 'E')
2748 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
2749 purge_addressof_1 (&XVECEXP (x
, i
, j
), insn
, force
);
2753 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
2754 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
2758 purge_addressof (insns
)
2762 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
2763 if (GET_CODE (insn
) == INSN
|| GET_CODE (insn
) == JUMP_INSN
2764 || GET_CODE (insn
) == CALL_INSN
)
2766 purge_addressof_1 (&PATTERN (insn
), insn
,
2767 asm_noperands (PATTERN (insn
)) > 0);
2768 purge_addressof_1 (®_NOTES (insn
), NULL_RTX
, 0);
2772 /* Pass through the INSNS of function FNDECL and convert virtual register
2773 references to hard register references. */
2776 instantiate_virtual_regs (fndecl
, insns
)
2783 /* Compute the offsets to use for this function. */
2784 in_arg_offset
= FIRST_PARM_OFFSET (fndecl
);
2785 var_offset
= STARTING_FRAME_OFFSET
;
2786 dynamic_offset
= STACK_DYNAMIC_OFFSET (fndecl
);
2787 out_arg_offset
= STACK_POINTER_OFFSET
;
2789 /* Scan all variables and parameters of this function. For each that is
2790 in memory, instantiate all virtual registers if the result is a valid
2791 address. If not, we do it later. That will handle most uses of virtual
2792 regs on many machines. */
2793 instantiate_decls (fndecl
, 1);
2795 /* Initialize recognition, indicating that volatile is OK. */
2798 /* Scan through all the insns, instantiating every virtual register still
2800 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
2801 if (GET_CODE (insn
) == INSN
|| GET_CODE (insn
) == JUMP_INSN
2802 || GET_CODE (insn
) == CALL_INSN
)
2804 instantiate_virtual_regs_1 (&PATTERN (insn
), insn
, 1);
2805 instantiate_virtual_regs_1 (®_NOTES (insn
), NULL_RTX
, 0);
2808 /* Instantiate the stack slots for the parm registers, for later use in
2809 addressof elimination. */
2810 for (i
= 0; i
< max_parm_reg
; ++i
)
2811 if (parm_reg_stack_loc
[i
])
2812 instantiate_virtual_regs_1 (&parm_reg_stack_loc
[i
], NULL_RTX
, 0);
2814 /* Now instantiate the remaining register equivalences for debugging info.
2815 These will not be valid addresses. */
2816 instantiate_decls (fndecl
, 0);
2818 /* Indicate that, from now on, assign_stack_local should use
2819 frame_pointer_rtx. */
2820 virtuals_instantiated
= 1;
2823 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
2824 all virtual registers in their DECL_RTL's.
2826 If VALID_ONLY, do this only if the resulting address is still valid.
2827 Otherwise, always do it. */
2830 instantiate_decls (fndecl
, valid_only
)
2836 if (DECL_SAVED_INSNS (fndecl
))
2837 /* When compiling an inline function, the obstack used for
2838 rtl allocation is the maybepermanent_obstack. Calling
2839 `resume_temporary_allocation' switches us back to that
2840 obstack while we process this function's parameters. */
2841 resume_temporary_allocation ();
2843 /* Process all parameters of the function. */
2844 for (decl
= DECL_ARGUMENTS (fndecl
); decl
; decl
= TREE_CHAIN (decl
))
2846 int size
= int_size_in_bytes (TREE_TYPE (decl
));
2847 instantiate_decl (DECL_RTL (decl
), size
, valid_only
);
2849 /* If the parameter was promoted, then the incoming RTL mode may be
2850 larger than the declared type size. We must use the larger of
2852 size
= MAX (GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl
))), size
);
2853 instantiate_decl (DECL_INCOMING_RTL (decl
), size
, valid_only
);
2856 /* Now process all variables defined in the function or its subblocks. */
2857 instantiate_decls_1 (DECL_INITIAL (fndecl
), valid_only
);
2859 if (DECL_INLINE (fndecl
) || DECL_DEFER_OUTPUT (fndecl
))
2861 /* Save all rtl allocated for this function by raising the
2862 high-water mark on the maybepermanent_obstack. */
2864 /* All further rtl allocation is now done in the current_obstack. */
2865 rtl_in_current_obstack ();
2869 /* Subroutine of instantiate_decls: Process all decls in the given
2870 BLOCK node and all its subblocks. */
2873 instantiate_decls_1 (let
, valid_only
)
2879 for (t
= BLOCK_VARS (let
); t
; t
= TREE_CHAIN (t
))
2880 instantiate_decl (DECL_RTL (t
), int_size_in_bytes (TREE_TYPE (t
)),
2883 /* Process all subblocks. */
2884 for (t
= BLOCK_SUBBLOCKS (let
); t
; t
= TREE_CHAIN (t
))
2885 instantiate_decls_1 (t
, valid_only
);
2888 /* Subroutine of the preceding procedures: Given RTL representing a
2889 decl and the size of the object, do any instantiation required.
2891 If VALID_ONLY is non-zero, it means that the RTL should only be
2892 changed if the new address is valid. */
2895 instantiate_decl (x
, size
, valid_only
)
2900 enum machine_mode mode
;
2903 /* If this is not a MEM, no need to do anything. Similarly if the
2904 address is a constant or a register that is not a virtual register. */
2906 if (x
== 0 || GET_CODE (x
) != MEM
)
2910 if (CONSTANT_P (addr
)
2911 || (GET_CODE (addr
) == ADDRESSOF
&& GET_CODE (XEXP (addr
, 0)) == REG
)
2912 || (GET_CODE (addr
) == REG
2913 && (REGNO (addr
) < FIRST_VIRTUAL_REGISTER
2914 || REGNO (addr
) > LAST_VIRTUAL_REGISTER
)))
2917 /* If we should only do this if the address is valid, copy the address.
2918 We need to do this so we can undo any changes that might make the
2919 address invalid. This copy is unfortunate, but probably can't be
2923 addr
= copy_rtx (addr
);
2925 instantiate_virtual_regs_1 (&addr
, NULL_RTX
, 0);
2929 /* Now verify that the resulting address is valid for every integer or
2930 floating-point mode up to and including SIZE bytes long. We do this
2931 since the object might be accessed in any mode and frame addresses
2934 for (mode
= GET_CLASS_NARROWEST_MODE (MODE_INT
);
2935 mode
!= VOIDmode
&& GET_MODE_SIZE (mode
) <= size
;
2936 mode
= GET_MODE_WIDER_MODE (mode
))
2937 if (! memory_address_p (mode
, addr
))
2940 for (mode
= GET_CLASS_NARROWEST_MODE (MODE_FLOAT
);
2941 mode
!= VOIDmode
&& GET_MODE_SIZE (mode
) <= size
;
2942 mode
= GET_MODE_WIDER_MODE (mode
))
2943 if (! memory_address_p (mode
, addr
))
2947 /* Put back the address now that we have updated it and we either know
2948 it is valid or we don't care whether it is valid. */
2953 /* Given a pointer to a piece of rtx and an optional pointer to the
2954 containing object, instantiate any virtual registers present in it.
2956 If EXTRA_INSNS, we always do the replacement and generate
2957 any extra insns before OBJECT. If it zero, we do nothing if replacement
2960 Return 1 if we either had nothing to do or if we were able to do the
2961 needed replacement. Return 0 otherwise; we only return zero if
2962 EXTRA_INSNS is zero.
2964 We first try some simple transformations to avoid the creation of extra
2968 instantiate_virtual_regs_1 (loc
, object
, extra_insns
)
2982 /* Re-start here to avoid recursion in common cases. */
2989 code
= GET_CODE (x
);
2991 /* Check for some special cases. */
3008 /* We are allowed to set the virtual registers. This means that
3009 that the actual register should receive the source minus the
3010 appropriate offset. This is used, for example, in the handling
3011 of non-local gotos. */
3012 if (SET_DEST (x
) == virtual_incoming_args_rtx
)
3013 new = arg_pointer_rtx
, offset
= - in_arg_offset
;
3014 else if (SET_DEST (x
) == virtual_stack_vars_rtx
)
3015 new = frame_pointer_rtx
, offset
= - var_offset
;
3016 else if (SET_DEST (x
) == virtual_stack_dynamic_rtx
)
3017 new = stack_pointer_rtx
, offset
= - dynamic_offset
;
3018 else if (SET_DEST (x
) == virtual_outgoing_args_rtx
)
3019 new = stack_pointer_rtx
, offset
= - out_arg_offset
;
3023 /* The only valid sources here are PLUS or REG. Just do
3024 the simplest possible thing to handle them. */
3025 if (GET_CODE (SET_SRC (x
)) != REG
3026 && GET_CODE (SET_SRC (x
)) != PLUS
)
3030 if (GET_CODE (SET_SRC (x
)) != REG
)
3031 temp
= force_operand (SET_SRC (x
), NULL_RTX
);
3034 temp
= force_operand (plus_constant (temp
, offset
), NULL_RTX
);
3038 emit_insns_before (seq
, object
);
3041 if (! validate_change (object
, &SET_SRC (x
), temp
, 0)
3048 instantiate_virtual_regs_1 (&SET_DEST (x
), object
, extra_insns
);
3053 /* Handle special case of virtual register plus constant. */
3054 if (CONSTANT_P (XEXP (x
, 1)))
3056 rtx old
, new_offset
;
3058 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3059 if (GET_CODE (XEXP (x
, 0)) == PLUS
)
3061 rtx inner
= XEXP (XEXP (x
, 0), 0);
3063 if (inner
== virtual_incoming_args_rtx
)
3064 new = arg_pointer_rtx
, offset
= in_arg_offset
;
3065 else if (inner
== virtual_stack_vars_rtx
)
3066 new = frame_pointer_rtx
, offset
= var_offset
;
3067 else if (inner
== virtual_stack_dynamic_rtx
)
3068 new = stack_pointer_rtx
, offset
= dynamic_offset
;
3069 else if (inner
== virtual_outgoing_args_rtx
)
3070 new = stack_pointer_rtx
, offset
= out_arg_offset
;
3077 instantiate_virtual_regs_1 (&XEXP (XEXP (x
, 0), 1), object
,
3079 new = gen_rtx_PLUS (Pmode
, new, XEXP (XEXP (x
, 0), 1));
3082 else if (XEXP (x
, 0) == virtual_incoming_args_rtx
)
3083 new = arg_pointer_rtx
, offset
= in_arg_offset
;
3084 else if (XEXP (x
, 0) == virtual_stack_vars_rtx
)
3085 new = frame_pointer_rtx
, offset
= var_offset
;
3086 else if (XEXP (x
, 0) == virtual_stack_dynamic_rtx
)
3087 new = stack_pointer_rtx
, offset
= dynamic_offset
;
3088 else if (XEXP (x
, 0) == virtual_outgoing_args_rtx
)
3089 new = stack_pointer_rtx
, offset
= out_arg_offset
;
3092 /* We know the second operand is a constant. Unless the
3093 first operand is a REG (which has been already checked),
3094 it needs to be checked. */
3095 if (GET_CODE (XEXP (x
, 0)) != REG
)
3103 new_offset
= plus_constant (XEXP (x
, 1), offset
);
3105 /* If the new constant is zero, try to replace the sum with just
3107 if (new_offset
== const0_rtx
3108 && validate_change (object
, loc
, new, 0))
3111 /* Next try to replace the register and new offset.
3112 There are two changes to validate here and we can't assume that
3113 in the case of old offset equals new just changing the register
3114 will yield a valid insn. In the interests of a little efficiency,
3115 however, we only call validate change once (we don't queue up the
3116 changes and then call apply_change_group). */
3120 ? ! validate_change (object
, &XEXP (x
, 0), new, 0)
3121 : (XEXP (x
, 0) = new,
3122 ! validate_change (object
, &XEXP (x
, 1), new_offset
, 0)))
3130 /* Otherwise copy the new constant into a register and replace
3131 constant with that register. */
3132 temp
= gen_reg_rtx (Pmode
);
3134 if (validate_change (object
, &XEXP (x
, 1), temp
, 0))
3135 emit_insn_before (gen_move_insn (temp
, new_offset
), object
);
3138 /* If that didn't work, replace this expression with a
3139 register containing the sum. */
3142 new = gen_rtx_PLUS (Pmode
, new, new_offset
);
3145 temp
= force_operand (new, NULL_RTX
);
3149 emit_insns_before (seq
, object
);
3150 if (! validate_change (object
, loc
, temp
, 0)
3151 && ! validate_replace_rtx (x
, temp
, object
))
3159 /* Fall through to generic two-operand expression case. */
3165 case DIV
: case UDIV
:
3166 case MOD
: case UMOD
:
3167 case AND
: case IOR
: case XOR
:
3168 case ROTATERT
: case ROTATE
:
3169 case ASHIFTRT
: case LSHIFTRT
: case ASHIFT
:
3171 case GE
: case GT
: case GEU
: case GTU
:
3172 case LE
: case LT
: case LEU
: case LTU
:
3173 if (XEXP (x
, 1) && ! CONSTANT_P (XEXP (x
, 1)))
3174 instantiate_virtual_regs_1 (&XEXP (x
, 1), object
, extra_insns
);
3179 /* Most cases of MEM that convert to valid addresses have already been
3180 handled by our scan of decls. The only special handling we
3181 need here is to make a copy of the rtx to ensure it isn't being
3182 shared if we have to change it to a pseudo.
3184 If the rtx is a simple reference to an address via a virtual register,
3185 it can potentially be shared. In such cases, first try to make it
3186 a valid address, which can also be shared. Otherwise, copy it and
3189 First check for common cases that need no processing. These are
3190 usually due to instantiation already being done on a previous instance
3194 if (CONSTANT_ADDRESS_P (temp
)
3195 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3196 || temp
== arg_pointer_rtx
3198 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3199 || temp
== hard_frame_pointer_rtx
3201 || temp
== frame_pointer_rtx
)
3204 if (GET_CODE (temp
) == PLUS
3205 && CONSTANT_ADDRESS_P (XEXP (temp
, 1))
3206 && (XEXP (temp
, 0) == frame_pointer_rtx
3207 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3208 || XEXP (temp
, 0) == hard_frame_pointer_rtx
3210 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3211 || XEXP (temp
, 0) == arg_pointer_rtx
3216 if (temp
== virtual_stack_vars_rtx
3217 || temp
== virtual_incoming_args_rtx
3218 || (GET_CODE (temp
) == PLUS
3219 && CONSTANT_ADDRESS_P (XEXP (temp
, 1))
3220 && (XEXP (temp
, 0) == virtual_stack_vars_rtx
3221 || XEXP (temp
, 0) == virtual_incoming_args_rtx
)))
3223 /* This MEM may be shared. If the substitution can be done without
3224 the need to generate new pseudos, we want to do it in place
3225 so all copies of the shared rtx benefit. The call below will
3226 only make substitutions if the resulting address is still
3229 Note that we cannot pass X as the object in the recursive call
3230 since the insn being processed may not allow all valid
3231 addresses. However, if we were not passed on object, we can
3232 only modify X without copying it if X will have a valid
3235 ??? Also note that this can still lose if OBJECT is an insn that
3236 has less restrictions on an address that some other insn.
3237 In that case, we will modify the shared address. This case
3238 doesn't seem very likely, though. One case where this could
3239 happen is in the case of a USE or CLOBBER reference, but we
3240 take care of that below. */
3242 if (instantiate_virtual_regs_1 (&XEXP (x
, 0),
3243 object
? object
: x
, 0))
3246 /* Otherwise make a copy and process that copy. We copy the entire
3247 RTL expression since it might be a PLUS which could also be
3249 *loc
= x
= copy_rtx (x
);
3252 /* Fall through to generic unary operation case. */
3254 case STRICT_LOW_PART
:
3256 case PRE_DEC
: case PRE_INC
: case POST_DEC
: case POST_INC
:
3257 case SIGN_EXTEND
: case ZERO_EXTEND
:
3258 case TRUNCATE
: case FLOAT_EXTEND
: case FLOAT_TRUNCATE
:
3259 case FLOAT
: case FIX
:
3260 case UNSIGNED_FIX
: case UNSIGNED_FLOAT
:
3264 /* These case either have just one operand or we know that we need not
3265 check the rest of the operands. */
3271 /* If the operand is a MEM, see if the change is a valid MEM. If not,
3272 go ahead and make the invalid one, but do it to a copy. For a REG,
3273 just make the recursive call, since there's no chance of a problem. */
3275 if ((GET_CODE (XEXP (x
, 0)) == MEM
3276 && instantiate_virtual_regs_1 (&XEXP (XEXP (x
, 0), 0), XEXP (x
, 0),
3278 || (GET_CODE (XEXP (x
, 0)) == REG
3279 && instantiate_virtual_regs_1 (&XEXP (x
, 0), object
, 0)))
3282 XEXP (x
, 0) = copy_rtx (XEXP (x
, 0));
3287 /* Try to replace with a PLUS. If that doesn't work, compute the sum
3288 in front of this insn and substitute the temporary. */
3289 if (x
== virtual_incoming_args_rtx
)
3290 new = arg_pointer_rtx
, offset
= in_arg_offset
;
3291 else if (x
== virtual_stack_vars_rtx
)
3292 new = frame_pointer_rtx
, offset
= var_offset
;
3293 else if (x
== virtual_stack_dynamic_rtx
)
3294 new = stack_pointer_rtx
, offset
= dynamic_offset
;
3295 else if (x
== virtual_outgoing_args_rtx
)
3296 new = stack_pointer_rtx
, offset
= out_arg_offset
;
3300 temp
= plus_constant (new, offset
);
3301 if (!validate_change (object
, loc
, temp
, 0))
3307 temp
= force_operand (temp
, NULL_RTX
);
3311 emit_insns_before (seq
, object
);
3312 if (! validate_change (object
, loc
, temp
, 0)
3313 && ! validate_replace_rtx (x
, temp
, object
))
3321 if (GET_CODE (XEXP (x
, 0)) == REG
)
3324 else if (GET_CODE (XEXP (x
, 0)) == MEM
)
3326 /* If we have a (addressof (mem ..)), do any instantiation inside
3327 since we know we'll be making the inside valid when we finally
3328 remove the ADDRESSOF. */
3329 instantiate_virtual_regs_1 (&XEXP (XEXP (x
, 0), 0), NULL_RTX
, 0);
3338 /* Scan all subexpressions. */
3339 fmt
= GET_RTX_FORMAT (code
);
3340 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
3343 if (!instantiate_virtual_regs_1 (&XEXP (x
, i
), object
, extra_insns
))
3346 else if (*fmt
== 'E')
3347 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
3348 if (! instantiate_virtual_regs_1 (&XVECEXP (x
, i
, j
), object
,
3355 /* Optimization: assuming this function does not receive nonlocal gotos,
3356 delete the handlers for such, as well as the insns to establish
3357 and disestablish them. */
3363 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
3365 /* Delete the handler by turning off the flag that would
3366 prevent jump_optimize from deleting it.
3367 Also permit deletion of the nonlocal labels themselves
3368 if nothing local refers to them. */
3369 if (GET_CODE (insn
) == CODE_LABEL
)
3373 LABEL_PRESERVE_P (insn
) = 0;
3375 /* Remove it from the nonlocal_label list, to avoid confusing
3377 for (t
= nonlocal_labels
, last_t
= 0; t
;
3378 last_t
= t
, t
= TREE_CHAIN (t
))
3379 if (DECL_RTL (TREE_VALUE (t
)) == insn
)
3384 nonlocal_labels
= TREE_CHAIN (nonlocal_labels
);
3386 TREE_CHAIN (last_t
) = TREE_CHAIN (t
);
3389 if (GET_CODE (insn
) == INSN
3390 && ((nonlocal_goto_handler_slot
!= 0
3391 && reg_mentioned_p (nonlocal_goto_handler_slot
, PATTERN (insn
)))
3392 || (nonlocal_goto_stack_level
!= 0
3393 && reg_mentioned_p (nonlocal_goto_stack_level
,
3399 /* Return a list (chain of EXPR_LIST nodes) for the nonlocal labels
3400 of the current function. */
3403 nonlocal_label_rtx_list ()
3408 for (t
= nonlocal_labels
; t
; t
= TREE_CHAIN (t
))
3409 x
= gen_rtx_EXPR_LIST (VOIDmode
, label_rtx (TREE_VALUE (t
)), x
);
3414 /* Output a USE for any register use in RTL.
3415 This is used with -noreg to mark the extent of lifespan
3416 of any registers used in a user-visible variable's DECL_RTL. */
3422 if (GET_CODE (rtl
) == REG
)
3423 /* This is a register variable. */
3424 emit_insn (gen_rtx_USE (VOIDmode
, rtl
));
3425 else if (GET_CODE (rtl
) == MEM
3426 && GET_CODE (XEXP (rtl
, 0)) == REG
3427 && (REGNO (XEXP (rtl
, 0)) < FIRST_VIRTUAL_REGISTER
3428 || REGNO (XEXP (rtl
, 0)) > LAST_VIRTUAL_REGISTER
)
3429 && XEXP (rtl
, 0) != current_function_internal_arg_pointer
)
3430 /* This is a variable-sized structure. */
3431 emit_insn (gen_rtx_USE (VOIDmode
, XEXP (rtl
, 0)));
3434 /* Like use_variable except that it outputs the USEs after INSN
3435 instead of at the end of the insn-chain. */
3438 use_variable_after (rtl
, insn
)
3441 if (GET_CODE (rtl
) == REG
)
3442 /* This is a register variable. */
3443 emit_insn_after (gen_rtx_USE (VOIDmode
, rtl
), insn
);
3444 else if (GET_CODE (rtl
) == MEM
3445 && GET_CODE (XEXP (rtl
, 0)) == REG
3446 && (REGNO (XEXP (rtl
, 0)) < FIRST_VIRTUAL_REGISTER
3447 || REGNO (XEXP (rtl
, 0)) > LAST_VIRTUAL_REGISTER
)
3448 && XEXP (rtl
, 0) != current_function_internal_arg_pointer
)
3449 /* This is a variable-sized structure. */
3450 emit_insn_after (gen_rtx_USE (VOIDmode
, XEXP (rtl
, 0)), insn
);
3456 return max_parm_reg
;
3459 /* Return the first insn following those generated by `assign_parms'. */
3462 get_first_nonparm_insn ()
3465 return NEXT_INSN (last_parm_insn
);
3466 return get_insns ();
3469 /* Return the first NOTE_INSN_BLOCK_BEG note in the function.
3470 Crash if there is none. */
3473 get_first_block_beg ()
3475 register rtx searcher
;
3476 register rtx insn
= get_first_nonparm_insn ();
3478 for (searcher
= insn
; searcher
; searcher
= NEXT_INSN (searcher
))
3479 if (GET_CODE (searcher
) == NOTE
3480 && NOTE_LINE_NUMBER (searcher
) == NOTE_INSN_BLOCK_BEG
)
3483 abort (); /* Invalid call to this function. (See comments above.) */
3487 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
3488 This means a type for which function calls must pass an address to the
3489 function or get an address back from the function.
3490 EXP may be a type node or an expression (whose type is tested). */
3493 aggregate_value_p (exp
)
3496 int i
, regno
, nregs
;
3499 if (TREE_CODE_CLASS (TREE_CODE (exp
)) == 't')
3502 type
= TREE_TYPE (exp
);
3504 if (RETURN_IN_MEMORY (type
))
3506 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
3507 and thus can't be returned in registers. */
3508 if (TREE_ADDRESSABLE (type
))
3510 if (flag_pcc_struct_return
&& AGGREGATE_TYPE_P (type
))
3512 /* Make sure we have suitable call-clobbered regs to return
3513 the value in; if not, we must return it in memory. */
3514 reg
= hard_function_value (type
, 0);
3516 /* If we have something other than a REG (e.g. a PARALLEL), then assume
3518 if (GET_CODE (reg
) != REG
)
3521 regno
= REGNO (reg
);
3522 nregs
= HARD_REGNO_NREGS (regno
, TYPE_MODE (type
));
3523 for (i
= 0; i
< nregs
; i
++)
3524 if (! call_used_regs
[regno
+ i
])
3529 /* Assign RTL expressions to the function's parameters.
3530 This may involve copying them into registers and using
3531 those registers as the RTL for them.
3533 If SECOND_TIME is non-zero it means that this function is being
3534 called a second time. This is done by integrate.c when a function's
3535 compilation is deferred. We need to come back here in case the
3536 FUNCTION_ARG macro computes items needed for the rest of the compilation
3537 (such as changing which registers are fixed or caller-saved). But suppress
3538 writing any insns or setting DECL_RTL of anything in this case. */
3541 assign_parms (fndecl
, second_time
)
3546 register rtx entry_parm
= 0;
3547 register rtx stack_parm
= 0;
3548 CUMULATIVE_ARGS args_so_far
;
3549 enum machine_mode promoted_mode
, passed_mode
;
3550 enum machine_mode nominal_mode
, promoted_nominal_mode
;
3552 /* Total space needed so far for args on the stack,
3553 given as a constant and a tree-expression. */
3554 struct args_size stack_args_size
;
3555 tree fntype
= TREE_TYPE (fndecl
);
3556 tree fnargs
= DECL_ARGUMENTS (fndecl
);
3557 /* This is used for the arg pointer when referring to stack args. */
3558 rtx internal_arg_pointer
;
3559 /* This is a dummy PARM_DECL that we used for the function result if
3560 the function returns a structure. */
3561 tree function_result_decl
= 0;
3562 int varargs_setup
= 0;
3563 rtx conversion_insns
= 0;
3565 /* Nonzero if the last arg is named `__builtin_va_alist',
3566 which is used on some machines for old-fashioned non-ANSI varargs.h;
3567 this should be stuck onto the stack as if it had arrived there. */
3569 = (current_function_varargs
3571 && (parm
= tree_last (fnargs
)) != 0
3573 && (! strcmp (IDENTIFIER_POINTER (DECL_NAME (parm
)),
3574 "__builtin_va_alist")));
3576 /* Nonzero if function takes extra anonymous args.
3577 This means the last named arg must be on the stack
3578 right before the anonymous ones. */
3580 = (TYPE_ARG_TYPES (fntype
) != 0
3581 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype
)))
3582 != void_type_node
));
3584 current_function_stdarg
= stdarg
;
3586 /* If the reg that the virtual arg pointer will be translated into is
3587 not a fixed reg or is the stack pointer, make a copy of the virtual
3588 arg pointer, and address parms via the copy. The frame pointer is
3589 considered fixed even though it is not marked as such.
3591 The second time through, simply use ap to avoid generating rtx. */
3593 if ((ARG_POINTER_REGNUM
== STACK_POINTER_REGNUM
3594 || ! (fixed_regs
[ARG_POINTER_REGNUM
]
3595 || ARG_POINTER_REGNUM
== FRAME_POINTER_REGNUM
))
3597 internal_arg_pointer
= copy_to_reg (virtual_incoming_args_rtx
);
3599 internal_arg_pointer
= virtual_incoming_args_rtx
;
3600 current_function_internal_arg_pointer
= internal_arg_pointer
;
3602 stack_args_size
.constant
= 0;
3603 stack_args_size
.var
= 0;
3605 /* If struct value address is treated as the first argument, make it so. */
3606 if (aggregate_value_p (DECL_RESULT (fndecl
))
3607 && ! current_function_returns_pcc_struct
3608 && struct_value_incoming_rtx
== 0)
3610 tree type
= build_pointer_type (TREE_TYPE (fntype
));
3612 function_result_decl
= build_decl (PARM_DECL
, NULL_TREE
, type
);
3614 DECL_ARG_TYPE (function_result_decl
) = type
;
3615 TREE_CHAIN (function_result_decl
) = fnargs
;
3616 fnargs
= function_result_decl
;
3619 max_parm_reg
= LAST_VIRTUAL_REGISTER
+ 1;
3620 parm_reg_stack_loc
= (rtx
*) savealloc (max_parm_reg
* sizeof (rtx
));
3621 bzero ((char *) parm_reg_stack_loc
, max_parm_reg
* sizeof (rtx
));
3623 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
3624 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far
, fntype
, NULL_RTX
);
3626 INIT_CUMULATIVE_ARGS (args_so_far
, fntype
, NULL_RTX
, 0);
3629 /* We haven't yet found an argument that we must push and pretend the
3631 current_function_pretend_args_size
= 0;
3633 for (parm
= fnargs
; parm
; parm
= TREE_CHAIN (parm
))
3635 int aggregate
= AGGREGATE_TYPE_P (TREE_TYPE (parm
));
3636 struct args_size stack_offset
;
3637 struct args_size arg_size
;
3638 int passed_pointer
= 0;
3639 int did_conversion
= 0;
3640 tree passed_type
= DECL_ARG_TYPE (parm
);
3641 tree nominal_type
= TREE_TYPE (parm
);
3643 /* Set LAST_NAMED if this is last named arg before some
3645 int last_named
= ((TREE_CHAIN (parm
) == 0
3646 || DECL_NAME (TREE_CHAIN (parm
)) == 0)
3647 && (stdarg
|| current_function_varargs
));
3648 /* Set NAMED_ARG if this arg should be treated as a named arg. For
3649 most machines, if this is a varargs/stdarg function, then we treat
3650 the last named arg as if it were anonymous too. */
3651 #ifdef STRICT_ARGUMENT_NAMING
3654 int named_arg
= ! last_named
;
3656 /* If this is a varargs function, then we want to treat the last named
3657 argument as if it was an aggregate, because it might be accessed as
3658 one by the va_arg macros. This is necessary to make the aliasing
3659 code handle this parm correctly. */
3660 if (hide_last_arg
&& last_named
)
3663 if (TREE_TYPE (parm
) == error_mark_node
3664 /* This can happen after weird syntax errors
3665 or if an enum type is defined among the parms. */
3666 || TREE_CODE (parm
) != PARM_DECL
3667 || passed_type
== NULL
)
3669 DECL_INCOMING_RTL (parm
) = DECL_RTL (parm
)
3670 = gen_rtx_MEM (BLKmode
, const0_rtx
);
3671 TREE_USED (parm
) = 1;
3675 /* For varargs.h function, save info about regs and stack space
3676 used by the individual args, not including the va_alist arg. */
3677 if (hide_last_arg
&& last_named
)
3678 current_function_args_info
= args_so_far
;
3680 /* Find mode of arg as it is passed, and mode of arg
3681 as it should be during execution of this function. */
3682 passed_mode
= TYPE_MODE (passed_type
);
3683 nominal_mode
= TYPE_MODE (nominal_type
);
3685 /* If the parm's mode is VOID, its value doesn't matter,
3686 and avoid the usual things like emit_move_insn that could crash. */
3687 if (nominal_mode
== VOIDmode
)
3689 DECL_INCOMING_RTL (parm
) = DECL_RTL (parm
) = const0_rtx
;
3693 /* If the parm is to be passed as a transparent union, use the
3694 type of the first field for the tests below. We have already
3695 verified that the modes are the same. */
3696 if (DECL_TRANSPARENT_UNION (parm
)
3697 || TYPE_TRANSPARENT_UNION (passed_type
))
3698 passed_type
= TREE_TYPE (TYPE_FIELDS (passed_type
));
3700 /* See if this arg was passed by invisible reference. It is if
3701 it is an object whose size depends on the contents of the
3702 object itself or if the machine requires these objects be passed
3705 if ((TREE_CODE (TYPE_SIZE (passed_type
)) != INTEGER_CST
3706 && contains_placeholder_p (TYPE_SIZE (passed_type
)))
3707 || TREE_ADDRESSABLE (passed_type
)
3708 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3709 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far
, passed_mode
,
3710 passed_type
, named_arg
)
3714 passed_type
= nominal_type
= build_pointer_type (passed_type
);
3716 passed_mode
= nominal_mode
= Pmode
;
3719 promoted_mode
= passed_mode
;
3721 #ifdef PROMOTE_FUNCTION_ARGS
3722 /* Compute the mode in which the arg is actually extended to. */
3723 promoted_mode
= promote_mode (passed_type
, promoted_mode
, &unsignedp
, 1);
3726 /* Let machine desc say which reg (if any) the parm arrives in.
3727 0 means it arrives on the stack. */
3728 #ifdef FUNCTION_INCOMING_ARG
3729 entry_parm
= FUNCTION_INCOMING_ARG (args_so_far
, promoted_mode
,
3730 passed_type
, named_arg
);
3732 entry_parm
= FUNCTION_ARG (args_so_far
, promoted_mode
,
3733 passed_type
, named_arg
);
3736 if (entry_parm
== 0)
3737 promoted_mode
= passed_mode
;
3739 #ifdef SETUP_INCOMING_VARARGS
3740 /* If this is the last named parameter, do any required setup for
3741 varargs or stdargs. We need to know about the case of this being an
3742 addressable type, in which case we skip the registers it
3743 would have arrived in.
3745 For stdargs, LAST_NAMED will be set for two parameters, the one that
3746 is actually the last named, and the dummy parameter. We only
3747 want to do this action once.
3749 Also, indicate when RTL generation is to be suppressed. */
3750 if (last_named
&& !varargs_setup
)
3752 SETUP_INCOMING_VARARGS (args_so_far
, promoted_mode
, passed_type
,
3753 current_function_pretend_args_size
,
3759 /* Determine parm's home in the stack,
3760 in case it arrives in the stack or we should pretend it did.
3762 Compute the stack position and rtx where the argument arrives
3765 There is one complexity here: If this was a parameter that would
3766 have been passed in registers, but wasn't only because it is
3767 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
3768 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
3769 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
3770 0 as it was the previous time. */
3772 locate_and_pad_parm (promoted_mode
, passed_type
,
3773 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3776 #ifdef FUNCTION_INCOMING_ARG
3777 FUNCTION_INCOMING_ARG (args_so_far
, promoted_mode
,
3780 || varargs_setup
)) != 0,
3782 FUNCTION_ARG (args_so_far
, promoted_mode
,
3784 named_arg
|| varargs_setup
) != 0,
3787 fndecl
, &stack_args_size
, &stack_offset
, &arg_size
);
3791 rtx offset_rtx
= ARGS_SIZE_RTX (stack_offset
);
3793 if (offset_rtx
== const0_rtx
)
3794 stack_parm
= gen_rtx_MEM (promoted_mode
, internal_arg_pointer
);
3796 stack_parm
= gen_rtx_MEM (promoted_mode
,
3797 gen_rtx_PLUS (Pmode
,
3798 internal_arg_pointer
,
3801 /* If this is a memory ref that contains aggregate components,
3802 mark it as such for cse and loop optimize. Likewise if it
3804 MEM_IN_STRUCT_P (stack_parm
) = aggregate
;
3805 RTX_UNCHANGING_P (stack_parm
) = TREE_READONLY (parm
);
3808 /* If this parameter was passed both in registers and in the stack,
3809 use the copy on the stack. */
3810 if (MUST_PASS_IN_STACK (promoted_mode
, passed_type
))
3813 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3814 /* If this parm was passed part in regs and part in memory,
3815 pretend it arrived entirely in memory
3816 by pushing the register-part onto the stack.
3818 In the special case of a DImode or DFmode that is split,
3819 we could put it together in a pseudoreg directly,
3820 but for now that's not worth bothering with. */
3824 int nregs
= FUNCTION_ARG_PARTIAL_NREGS (args_so_far
, promoted_mode
,
3825 passed_type
, named_arg
);
3829 current_function_pretend_args_size
3830 = (((nregs
* UNITS_PER_WORD
) + (PARM_BOUNDARY
/ BITS_PER_UNIT
) - 1)
3831 / (PARM_BOUNDARY
/ BITS_PER_UNIT
)
3832 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
3836 /* Handle calls that pass values in multiple non-contiguous
3837 locations. The Irix 6 ABI has examples of this. */
3838 if (GET_CODE (entry_parm
) == PARALLEL
)
3839 emit_group_store (validize_mem (stack_parm
),
3842 move_block_from_reg (REGNO (entry_parm
),
3843 validize_mem (stack_parm
), nregs
,
3844 int_size_in_bytes (TREE_TYPE (parm
)));
3846 entry_parm
= stack_parm
;
3851 /* If we didn't decide this parm came in a register,
3852 by default it came on the stack. */
3853 if (entry_parm
== 0)
3854 entry_parm
= stack_parm
;
3856 /* Record permanently how this parm was passed. */
3858 DECL_INCOMING_RTL (parm
) = entry_parm
;
3860 /* If there is actually space on the stack for this parm,
3861 count it in stack_args_size; otherwise set stack_parm to 0
3862 to indicate there is no preallocated stack slot for the parm. */
3864 if (entry_parm
== stack_parm
3865 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
3866 /* On some machines, even if a parm value arrives in a register
3867 there is still an (uninitialized) stack slot allocated for it.
3869 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
3870 whether this parameter already has a stack slot allocated,
3871 because an arg block exists only if current_function_args_size
3872 is larger than some threshold, and we haven't calculated that
3873 yet. So, for now, we just assume that stack slots never exist
3875 || REG_PARM_STACK_SPACE (fndecl
) > 0
3879 stack_args_size
.constant
+= arg_size
.constant
;
3881 ADD_PARM_SIZE (stack_args_size
, arg_size
.var
);
3884 /* No stack slot was pushed for this parm. */
3887 /* Update info on where next arg arrives in registers. */
3889 FUNCTION_ARG_ADVANCE (args_so_far
, promoted_mode
,
3890 passed_type
, named_arg
);
3892 /* If this is our second time through, we are done with this parm. */
3896 /* If we can't trust the parm stack slot to be aligned enough
3897 for its ultimate type, don't use that slot after entry.
3898 We'll make another stack slot, if we need one. */
3900 int thisparm_boundary
3901 = FUNCTION_ARG_BOUNDARY (promoted_mode
, passed_type
);
3903 if (GET_MODE_ALIGNMENT (nominal_mode
) > thisparm_boundary
)
3907 /* If parm was passed in memory, and we need to convert it on entry,
3908 don't store it back in that same slot. */
3910 && nominal_mode
!= BLKmode
&& nominal_mode
!= passed_mode
)
3914 /* Now adjust STACK_PARM to the mode and precise location
3915 where this parameter should live during execution,
3916 if we discover that it must live in the stack during execution.
3917 To make debuggers happier on big-endian machines, we store
3918 the value in the last bytes of the space available. */
3920 if (nominal_mode
!= BLKmode
&& nominal_mode
!= passed_mode
3925 if (BYTES_BIG_ENDIAN
3926 && GET_MODE_SIZE (nominal_mode
) < UNITS_PER_WORD
)
3927 stack_offset
.constant
+= (GET_MODE_SIZE (passed_mode
)
3928 - GET_MODE_SIZE (nominal_mode
));
3930 offset_rtx
= ARGS_SIZE_RTX (stack_offset
);
3931 if (offset_rtx
== const0_rtx
)
3932 stack_parm
= gen_rtx_MEM (nominal_mode
, internal_arg_pointer
);
3934 stack_parm
= gen_rtx_MEM (nominal_mode
,
3935 gen_rtx_PLUS (Pmode
,
3936 internal_arg_pointer
,
3939 /* If this is a memory ref that contains aggregate components,
3940 mark it as such for cse and loop optimize. */
3941 MEM_IN_STRUCT_P (stack_parm
) = aggregate
;
3946 /* We need this "use" info, because the gcc-register->stack-register
3947 converter in reg-stack.c needs to know which registers are active
3948 at the start of the function call. The actual parameter loading
3949 instructions are not always available then anymore, since they might
3950 have been optimised away. */
3952 if (GET_CODE (entry_parm
) == REG
&& !(hide_last_arg
&& last_named
))
3953 emit_insn (gen_rtx_USE (GET_MODE (entry_parm
), entry_parm
));
3956 /* ENTRY_PARM is an RTX for the parameter as it arrives,
3957 in the mode in which it arrives.
3958 STACK_PARM is an RTX for a stack slot where the parameter can live
3959 during the function (in case we want to put it there).
3960 STACK_PARM is 0 if no stack slot was pushed for it.
3962 Now output code if necessary to convert ENTRY_PARM to
3963 the type in which this function declares it,
3964 and store that result in an appropriate place,
3965 which may be a pseudo reg, may be STACK_PARM,
3966 or may be a local stack slot if STACK_PARM is 0.
3968 Set DECL_RTL to that place. */
3970 if (nominal_mode
== BLKmode
|| GET_CODE (entry_parm
) == PARALLEL
)
3972 /* If a BLKmode arrives in registers, copy it to a stack slot.
3973 Handle calls that pass values in multiple non-contiguous
3974 locations. The Irix 6 ABI has examples of this. */
3975 if (GET_CODE (entry_parm
) == REG
3976 || GET_CODE (entry_parm
) == PARALLEL
)
3979 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm
)),
3982 /* Note that we will be storing an integral number of words.
3983 So we have to be careful to ensure that we allocate an
3984 integral number of words. We do this below in the
3985 assign_stack_local if space was not allocated in the argument
3986 list. If it was, this will not work if PARM_BOUNDARY is not
3987 a multiple of BITS_PER_WORD. It isn't clear how to fix this
3988 if it becomes a problem. */
3990 if (stack_parm
== 0)
3993 = assign_stack_local (GET_MODE (entry_parm
),
3996 /* If this is a memory ref that contains aggregate
3997 components, mark it as such for cse and loop optimize. */
3998 MEM_IN_STRUCT_P (stack_parm
) = aggregate
;
4001 else if (PARM_BOUNDARY
% BITS_PER_WORD
!= 0)
4004 if (TREE_READONLY (parm
))
4005 RTX_UNCHANGING_P (stack_parm
) = 1;
4007 /* Handle calls that pass values in multiple non-contiguous
4008 locations. The Irix 6 ABI has examples of this. */
4009 if (GET_CODE (entry_parm
) == PARALLEL
)
4010 emit_group_store (validize_mem (stack_parm
), entry_parm
);
4012 move_block_from_reg (REGNO (entry_parm
),
4013 validize_mem (stack_parm
),
4014 size_stored
/ UNITS_PER_WORD
,
4015 int_size_in_bytes (TREE_TYPE (parm
)));
4017 DECL_RTL (parm
) = stack_parm
;
4019 else if (! ((obey_regdecls
&& ! DECL_REGISTER (parm
)
4020 && ! DECL_INLINE (fndecl
))
4021 /* layout_decl may set this. */
4022 || TREE_ADDRESSABLE (parm
)
4023 || TREE_SIDE_EFFECTS (parm
)
4024 /* If -ffloat-store specified, don't put explicit
4025 float variables into registers. */
4026 || (flag_float_store
4027 && TREE_CODE (TREE_TYPE (parm
)) == REAL_TYPE
))
4028 /* Always assign pseudo to structure return or item passed
4029 by invisible reference. */
4030 || passed_pointer
|| parm
== function_result_decl
)
4032 /* Store the parm in a pseudoregister during the function, but we
4033 may need to do it in a wider mode. */
4035 register rtx parmreg
;
4036 int regno
, regnoi
, regnor
;
4038 unsignedp
= TREE_UNSIGNED (TREE_TYPE (parm
));
4040 promoted_nominal_mode
4041 = promote_mode (TREE_TYPE (parm
), nominal_mode
, &unsignedp
, 0);
4043 parmreg
= gen_reg_rtx (promoted_nominal_mode
);
4044 mark_user_reg (parmreg
);
4046 /* If this was an item that we received a pointer to, set DECL_RTL
4051 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type
)), parmreg
);
4052 MEM_IN_STRUCT_P (DECL_RTL (parm
)) = aggregate
;
4055 DECL_RTL (parm
) = parmreg
;
4057 /* Copy the value into the register. */
4058 if (nominal_mode
!= passed_mode
4059 || promoted_nominal_mode
!= promoted_mode
)
4061 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4062 mode, by the caller. We now have to convert it to
4063 NOMINAL_MODE, if different. However, PARMREG may be in
4064 a different mode than NOMINAL_MODE if it is being stored
4067 If ENTRY_PARM is a hard register, it might be in a register
4068 not valid for operating in its mode (e.g., an odd-numbered
4069 register for a DFmode). In that case, moves are the only
4070 thing valid, so we can't do a convert from there. This
4071 occurs when the calling sequence allow such misaligned
4074 In addition, the conversion may involve a call, which could
4075 clobber parameters which haven't been copied to pseudo
4076 registers yet. Therefore, we must first copy the parm to
4077 a pseudo reg here, and save the conversion until after all
4078 parameters have been moved. */
4080 rtx tempreg
= gen_reg_rtx (GET_MODE (entry_parm
));
4082 emit_move_insn (tempreg
, validize_mem (entry_parm
));
4084 push_to_sequence (conversion_insns
);
4085 tempreg
= convert_to_mode (nominal_mode
, tempreg
, unsignedp
);
4087 expand_assignment (parm
,
4088 make_tree (nominal_type
, tempreg
), 0, 0);
4089 conversion_insns
= get_insns ();
4094 emit_move_insn (parmreg
, validize_mem (entry_parm
));
4096 /* If we were passed a pointer but the actual value
4097 can safely live in a register, put it in one. */
4098 if (passed_pointer
&& TYPE_MODE (TREE_TYPE (parm
)) != BLKmode
4099 && ! ((obey_regdecls
&& ! DECL_REGISTER (parm
)
4100 && ! DECL_INLINE (fndecl
))
4101 /* layout_decl may set this. */
4102 || TREE_ADDRESSABLE (parm
)
4103 || TREE_SIDE_EFFECTS (parm
)
4104 /* If -ffloat-store specified, don't put explicit
4105 float variables into registers. */
4106 || (flag_float_store
4107 && TREE_CODE (TREE_TYPE (parm
)) == REAL_TYPE
)))
4109 /* We can't use nominal_mode, because it will have been set to
4110 Pmode above. We must use the actual mode of the parm. */
4111 parmreg
= gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm
)));
4112 mark_user_reg (parmreg
);
4113 emit_move_insn (parmreg
, DECL_RTL (parm
));
4114 DECL_RTL (parm
) = parmreg
;
4115 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4119 #ifdef FUNCTION_ARG_CALLEE_COPIES
4120 /* If we are passed an arg by reference and it is our responsibility
4121 to make a copy, do it now.
4122 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4123 original argument, so we must recreate them in the call to
4124 FUNCTION_ARG_CALLEE_COPIES. */
4125 /* ??? Later add code to handle the case that if the argument isn't
4126 modified, don't do the copy. */
4128 else if (passed_pointer
4129 && FUNCTION_ARG_CALLEE_COPIES (args_so_far
,
4130 TYPE_MODE (DECL_ARG_TYPE (parm
)),
4131 DECL_ARG_TYPE (parm
),
4133 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm
)))
4136 tree type
= DECL_ARG_TYPE (parm
);
4138 /* This sequence may involve a library call perhaps clobbering
4139 registers that haven't been copied to pseudos yet. */
4141 push_to_sequence (conversion_insns
);
4143 if (TYPE_SIZE (type
) == 0
4144 || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
4145 /* This is a variable sized object. */
4146 copy
= gen_rtx_MEM (BLKmode
,
4147 allocate_dynamic_stack_space
4148 (expr_size (parm
), NULL_RTX
,
4149 TYPE_ALIGN (type
)));
4151 copy
= assign_stack_temp (TYPE_MODE (type
),
4152 int_size_in_bytes (type
), 1);
4153 MEM_IN_STRUCT_P (copy
) = AGGREGATE_TYPE_P (type
);
4154 RTX_UNCHANGING_P (copy
) = TREE_READONLY (parm
);
4156 store_expr (parm
, copy
, 0);
4157 emit_move_insn (parmreg
, XEXP (copy
, 0));
4158 if (flag_check_memory_usage
)
4159 emit_library_call (chkr_set_right_libfunc
, 1, VOIDmode
, 3,
4160 XEXP (copy
, 0), ptr_mode
,
4161 GEN_INT (int_size_in_bytes (type
)),
4162 TYPE_MODE (sizetype
),
4163 GEN_INT (MEMORY_USE_RW
),
4164 TYPE_MODE (integer_type_node
));
4165 conversion_insns
= get_insns ();
4169 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4171 /* In any case, record the parm's desired stack location
4172 in case we later discover it must live in the stack.
4174 If it is a COMPLEX value, store the stack location for both
4177 if (GET_CODE (parmreg
) == CONCAT
)
4178 regno
= MAX (REGNO (XEXP (parmreg
, 0)), REGNO (XEXP (parmreg
, 1)));
4180 regno
= REGNO (parmreg
);
4182 if (regno
>= max_parm_reg
)
4185 int old_max_parm_reg
= max_parm_reg
;
4187 /* It's slow to expand this one register at a time,
4188 but it's also rare and we need max_parm_reg to be
4189 precisely correct. */
4190 max_parm_reg
= regno
+ 1;
4191 new = (rtx
*) savealloc (max_parm_reg
* sizeof (rtx
));
4192 bcopy ((char *) parm_reg_stack_loc
, (char *) new,
4193 old_max_parm_reg
* sizeof (rtx
));
4194 bzero ((char *) (new + old_max_parm_reg
),
4195 (max_parm_reg
- old_max_parm_reg
) * sizeof (rtx
));
4196 parm_reg_stack_loc
= new;
4199 if (GET_CODE (parmreg
) == CONCAT
)
4201 enum machine_mode submode
= GET_MODE (XEXP (parmreg
, 0));
4203 regnor
= REGNO (gen_realpart (submode
, parmreg
));
4204 regnoi
= REGNO (gen_imagpart (submode
, parmreg
));
4206 if (stack_parm
!= 0)
4208 parm_reg_stack_loc
[regnor
]
4209 = gen_realpart (submode
, stack_parm
);
4210 parm_reg_stack_loc
[regnoi
]
4211 = gen_imagpart (submode
, stack_parm
);
4215 parm_reg_stack_loc
[regnor
] = 0;
4216 parm_reg_stack_loc
[regnoi
] = 0;
4220 parm_reg_stack_loc
[REGNO (parmreg
)] = stack_parm
;
4222 /* Mark the register as eliminable if we did no conversion
4223 and it was copied from memory at a fixed offset,
4224 and the arg pointer was not copied to a pseudo-reg.
4225 If the arg pointer is a pseudo reg or the offset formed
4226 an invalid address, such memory-equivalences
4227 as we make here would screw up life analysis for it. */
4228 if (nominal_mode
== passed_mode
4231 && GET_CODE (stack_parm
) == MEM
4232 && stack_offset
.var
== 0
4233 && reg_mentioned_p (virtual_incoming_args_rtx
,
4234 XEXP (stack_parm
, 0)))
4236 rtx linsn
= get_last_insn ();
4239 /* Mark complex types separately. */
4240 if (GET_CODE (parmreg
) == CONCAT
)
4241 /* Scan backwards for the set of the real and
4243 for (sinsn
= linsn
; sinsn
!= 0;
4244 sinsn
= prev_nonnote_insn (sinsn
))
4246 set
= single_set (sinsn
);
4248 && SET_DEST (set
) == regno_reg_rtx
[regnoi
])
4250 = gen_rtx_EXPR_LIST (REG_EQUIV
,
4251 parm_reg_stack_loc
[regnoi
],
4254 && SET_DEST (set
) == regno_reg_rtx
[regnor
])
4256 = gen_rtx_EXPR_LIST (REG_EQUIV
,
4257 parm_reg_stack_loc
[regnor
],
4260 else if ((set
= single_set (linsn
)) != 0
4261 && SET_DEST (set
) == parmreg
)
4263 = gen_rtx_EXPR_LIST (REG_EQUIV
,
4264 stack_parm
, REG_NOTES (linsn
));
4267 /* For pointer data type, suggest pointer register. */
4268 if (TREE_CODE (TREE_TYPE (parm
)) == POINTER_TYPE
)
4269 mark_reg_pointer (parmreg
,
4270 (TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
)))
4275 /* Value must be stored in the stack slot STACK_PARM
4276 during function execution. */
4278 if (promoted_mode
!= nominal_mode
)
4280 /* Conversion is required. */
4281 rtx tempreg
= gen_reg_rtx (GET_MODE (entry_parm
));
4283 emit_move_insn (tempreg
, validize_mem (entry_parm
));
4285 push_to_sequence (conversion_insns
);
4286 entry_parm
= convert_to_mode (nominal_mode
, tempreg
,
4287 TREE_UNSIGNED (TREE_TYPE (parm
)));
4290 /* ??? This may need a big-endian conversion on sparc64. */
4291 stack_parm
= change_address (stack_parm
, nominal_mode
,
4294 conversion_insns
= get_insns ();
4299 if (entry_parm
!= stack_parm
)
4301 if (stack_parm
== 0)
4304 = assign_stack_local (GET_MODE (entry_parm
),
4305 GET_MODE_SIZE (GET_MODE (entry_parm
)), 0);
4306 /* If this is a memory ref that contains aggregate components,
4307 mark it as such for cse and loop optimize. */
4308 MEM_IN_STRUCT_P (stack_parm
) = aggregate
;
4311 if (promoted_mode
!= nominal_mode
)
4313 push_to_sequence (conversion_insns
);
4314 emit_move_insn (validize_mem (stack_parm
),
4315 validize_mem (entry_parm
));
4316 conversion_insns
= get_insns ();
4320 emit_move_insn (validize_mem (stack_parm
),
4321 validize_mem (entry_parm
));
4323 if (flag_check_memory_usage
4324 && entry_parm
!= stack_parm
4325 && promoted_mode
!= nominal_mode
)
4327 push_to_sequence (conversion_insns
);
4328 emit_library_call (chkr_set_right_libfunc
, 1, VOIDmode
, 3,
4329 XEXP (stack_parm
, 0), ptr_mode
,
4330 GEN_INT (GET_MODE_SIZE (GET_MODE
4332 TYPE_MODE (sizetype
),
4333 GEN_INT (MEMORY_USE_RW
),
4334 TYPE_MODE (integer_type_node
));
4336 conversion_insns
= get_insns ();
4339 DECL_RTL (parm
) = stack_parm
;
4342 /* If this "parameter" was the place where we are receiving the
4343 function's incoming structure pointer, set up the result. */
4344 if (parm
== function_result_decl
)
4346 tree result
= DECL_RESULT (fndecl
);
4347 tree restype
= TREE_TYPE (result
);
4350 = gen_rtx_MEM (DECL_MODE (result
), DECL_RTL (parm
));
4352 MEM_IN_STRUCT_P (DECL_RTL (result
)) = AGGREGATE_TYPE_P (restype
);
4355 if (TREE_THIS_VOLATILE (parm
))
4356 MEM_VOLATILE_P (DECL_RTL (parm
)) = 1;
4357 if (TREE_READONLY (parm
))
4358 RTX_UNCHANGING_P (DECL_RTL (parm
)) = 1;
4361 /* Output all parameter conversion instructions (possibly including calls)
4362 now that all parameters have been copied out of hard registers. */
4363 emit_insns (conversion_insns
);
4365 last_parm_insn
= get_last_insn ();
4367 current_function_args_size
= stack_args_size
.constant
;
4369 /* Adjust function incoming argument size for alignment and
4372 #ifdef REG_PARM_STACK_SPACE
4373 #ifndef MAYBE_REG_PARM_STACK_SPACE
4374 current_function_args_size
= MAX (current_function_args_size
,
4375 REG_PARM_STACK_SPACE (fndecl
));
4379 #ifdef STACK_BOUNDARY
4380 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
4382 current_function_args_size
4383 = ((current_function_args_size
+ STACK_BYTES
- 1)
4384 / STACK_BYTES
) * STACK_BYTES
;
4387 #ifdef ARGS_GROW_DOWNWARD
4388 current_function_arg_offset_rtx
4389 = (stack_args_size
.var
== 0 ? GEN_INT (-stack_args_size
.constant
)
4390 : expand_expr (size_binop (MINUS_EXPR
, stack_args_size
.var
,
4391 size_int (-stack_args_size
.constant
)),
4392 NULL_RTX
, VOIDmode
, EXPAND_MEMORY_USE_BAD
));
4394 current_function_arg_offset_rtx
= ARGS_SIZE_RTX (stack_args_size
);
4397 /* See how many bytes, if any, of its args a function should try to pop
4400 current_function_pops_args
= RETURN_POPS_ARGS (fndecl
, TREE_TYPE (fndecl
),
4401 current_function_args_size
);
4403 /* For stdarg.h function, save info about
4404 regs and stack space used by the named args. */
4407 current_function_args_info
= args_so_far
;
4409 /* Set the rtx used for the function return value. Put this in its
4410 own variable so any optimizers that need this information don't have
4411 to include tree.h. Do this here so it gets done when an inlined
4412 function gets output. */
4414 current_function_return_rtx
= DECL_RTL (DECL_RESULT (fndecl
));
4417 /* Indicate whether REGNO is an incoming argument to the current function
4418 that was promoted to a wider mode. If so, return the RTX for the
4419 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
4420 that REGNO is promoted from and whether the promotion was signed or
4423 #ifdef PROMOTE_FUNCTION_ARGS
4426 promoted_input_arg (regno
, pmode
, punsignedp
)
4428 enum machine_mode
*pmode
;
4433 for (arg
= DECL_ARGUMENTS (current_function_decl
); arg
;
4434 arg
= TREE_CHAIN (arg
))
4435 if (GET_CODE (DECL_INCOMING_RTL (arg
)) == REG
4436 && REGNO (DECL_INCOMING_RTL (arg
)) == regno
4437 && TYPE_MODE (DECL_ARG_TYPE (arg
)) == TYPE_MODE (TREE_TYPE (arg
)))
4439 enum machine_mode mode
= TYPE_MODE (TREE_TYPE (arg
));
4440 int unsignedp
= TREE_UNSIGNED (TREE_TYPE (arg
));
4442 mode
= promote_mode (TREE_TYPE (arg
), mode
, &unsignedp
, 1);
4443 if (mode
== GET_MODE (DECL_INCOMING_RTL (arg
))
4444 && mode
!= DECL_MODE (arg
))
4446 *pmode
= DECL_MODE (arg
);
4447 *punsignedp
= unsignedp
;
4448 return DECL_INCOMING_RTL (arg
);
4457 /* Compute the size and offset from the start of the stacked arguments for a
4458 parm passed in mode PASSED_MODE and with type TYPE.
4460 INITIAL_OFFSET_PTR points to the current offset into the stacked
4463 The starting offset and size for this parm are returned in *OFFSET_PTR
4464 and *ARG_SIZE_PTR, respectively.
4466 IN_REGS is non-zero if the argument will be passed in registers. It will
4467 never be set if REG_PARM_STACK_SPACE is not defined.
4469 FNDECL is the function in which the argument was defined.
4471 There are two types of rounding that are done. The first, controlled by
4472 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
4473 list to be aligned to the specific boundary (in bits). This rounding
4474 affects the initial and starting offsets, but not the argument size.
4476 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
4477 optionally rounds the size of the parm to PARM_BOUNDARY. The
4478 initial offset is not affected by this rounding, while the size always
4479 is and the starting offset may be. */
4481 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
4482 initial_offset_ptr is positive because locate_and_pad_parm's
4483 callers pass in the total size of args so far as
4484 initial_offset_ptr. arg_size_ptr is always positive.*/
4487 locate_and_pad_parm (passed_mode
, type
, in_regs
, fndecl
,
4488 initial_offset_ptr
, offset_ptr
, arg_size_ptr
)
4489 enum machine_mode passed_mode
;
4493 struct args_size
*initial_offset_ptr
;
4494 struct args_size
*offset_ptr
;
4495 struct args_size
*arg_size_ptr
;
4498 = type
? size_in_bytes (type
) : size_int (GET_MODE_SIZE (passed_mode
));
4499 enum direction where_pad
= FUNCTION_ARG_PADDING (passed_mode
, type
);
4500 int boundary
= FUNCTION_ARG_BOUNDARY (passed_mode
, type
);
4502 #ifdef REG_PARM_STACK_SPACE
4503 /* If we have found a stack parm before we reach the end of the
4504 area reserved for registers, skip that area. */
4507 int reg_parm_stack_space
= 0;
4509 #ifdef MAYBE_REG_PARM_STACK_SPACE
4510 reg_parm_stack_space
= MAYBE_REG_PARM_STACK_SPACE
;
4512 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
4514 if (reg_parm_stack_space
> 0)
4516 if (initial_offset_ptr
->var
)
4518 initial_offset_ptr
->var
4519 = size_binop (MAX_EXPR
, ARGS_SIZE_TREE (*initial_offset_ptr
),
4520 size_int (reg_parm_stack_space
));
4521 initial_offset_ptr
->constant
= 0;
4523 else if (initial_offset_ptr
->constant
< reg_parm_stack_space
)
4524 initial_offset_ptr
->constant
= reg_parm_stack_space
;
4527 #endif /* REG_PARM_STACK_SPACE */
4529 arg_size_ptr
->var
= 0;
4530 arg_size_ptr
->constant
= 0;
4532 #ifdef ARGS_GROW_DOWNWARD
4533 if (initial_offset_ptr
->var
)
4535 offset_ptr
->constant
= 0;
4536 offset_ptr
->var
= size_binop (MINUS_EXPR
, integer_zero_node
,
4537 initial_offset_ptr
->var
);
4541 offset_ptr
->constant
= - initial_offset_ptr
->constant
;
4542 offset_ptr
->var
= 0;
4544 if (where_pad
!= none
4545 && (TREE_CODE (sizetree
) != INTEGER_CST
4546 || ((TREE_INT_CST_LOW (sizetree
) * BITS_PER_UNIT
) % PARM_BOUNDARY
)))
4547 sizetree
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
4548 SUB_PARM_SIZE (*offset_ptr
, sizetree
);
4549 if (where_pad
!= downward
)
4550 pad_to_arg_alignment (offset_ptr
, boundary
);
4551 if (initial_offset_ptr
->var
)
4553 arg_size_ptr
->var
= size_binop (MINUS_EXPR
,
4554 size_binop (MINUS_EXPR
,
4556 initial_offset_ptr
->var
),
4561 arg_size_ptr
->constant
= (- initial_offset_ptr
->constant
4562 - offset_ptr
->constant
);
4564 #else /* !ARGS_GROW_DOWNWARD */
4565 pad_to_arg_alignment (initial_offset_ptr
, boundary
);
4566 *offset_ptr
= *initial_offset_ptr
;
4568 #ifdef PUSH_ROUNDING
4569 if (passed_mode
!= BLKmode
)
4570 sizetree
= size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree
)));
4573 /* Pad_below needs the pre-rounded size to know how much to pad below
4574 so this must be done before rounding up. */
4575 if (where_pad
== downward
4576 /* However, BLKmode args passed in regs have their padding done elsewhere.
4577 The stack slot must be able to hold the entire register. */
4578 && !(in_regs
&& passed_mode
== BLKmode
))
4579 pad_below (offset_ptr
, passed_mode
, sizetree
);
4581 if (where_pad
!= none
4582 && (TREE_CODE (sizetree
) != INTEGER_CST
4583 || ((TREE_INT_CST_LOW (sizetree
) * BITS_PER_UNIT
) % PARM_BOUNDARY
)))
4584 sizetree
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
4586 ADD_PARM_SIZE (*arg_size_ptr
, sizetree
);
4587 #endif /* ARGS_GROW_DOWNWARD */
4590 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
4591 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
4594 pad_to_arg_alignment (offset_ptr
, boundary
)
4595 struct args_size
*offset_ptr
;
4598 int boundary_in_bytes
= boundary
/ BITS_PER_UNIT
;
4600 if (boundary
> BITS_PER_UNIT
)
4602 if (offset_ptr
->var
)
4605 #ifdef ARGS_GROW_DOWNWARD
4610 (ARGS_SIZE_TREE (*offset_ptr
),
4611 boundary
/ BITS_PER_UNIT
);
4612 offset_ptr
->constant
= 0; /*?*/
4615 offset_ptr
->constant
=
4616 #ifdef ARGS_GROW_DOWNWARD
4617 FLOOR_ROUND (offset_ptr
->constant
, boundary_in_bytes
);
4619 CEIL_ROUND (offset_ptr
->constant
, boundary_in_bytes
);
4624 #ifndef ARGS_GROW_DOWNWARD
4626 pad_below (offset_ptr
, passed_mode
, sizetree
)
4627 struct args_size
*offset_ptr
;
4628 enum machine_mode passed_mode
;
4631 if (passed_mode
!= BLKmode
)
4633 if (GET_MODE_BITSIZE (passed_mode
) % PARM_BOUNDARY
)
4634 offset_ptr
->constant
4635 += (((GET_MODE_BITSIZE (passed_mode
) + PARM_BOUNDARY
- 1)
4636 / PARM_BOUNDARY
* PARM_BOUNDARY
/ BITS_PER_UNIT
)
4637 - GET_MODE_SIZE (passed_mode
));
4641 if (TREE_CODE (sizetree
) != INTEGER_CST
4642 || (TREE_INT_CST_LOW (sizetree
) * BITS_PER_UNIT
) % PARM_BOUNDARY
)
4644 /* Round the size up to multiple of PARM_BOUNDARY bits. */
4645 tree s2
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
4647 ADD_PARM_SIZE (*offset_ptr
, s2
);
4648 SUB_PARM_SIZE (*offset_ptr
, sizetree
);
4655 round_down (value
, divisor
)
4659 return size_binop (MULT_EXPR
,
4660 size_binop (FLOOR_DIV_EXPR
, value
, size_int (divisor
)),
4661 size_int (divisor
));
4664 /* Walk the tree of blocks describing the binding levels within a function
4665 and warn about uninitialized variables.
4666 This is done after calling flow_analysis and before global_alloc
4667 clobbers the pseudo-regs to hard regs. */
4670 uninitialized_vars_warning (block
)
4673 register tree decl
, sub
;
4674 for (decl
= BLOCK_VARS (block
); decl
; decl
= TREE_CHAIN (decl
))
4676 if (TREE_CODE (decl
) == VAR_DECL
4677 /* These warnings are unreliable for and aggregates
4678 because assigning the fields one by one can fail to convince
4679 flow.c that the entire aggregate was initialized.
4680 Unions are troublesome because members may be shorter. */
4681 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl
))
4682 && DECL_RTL (decl
) != 0
4683 && GET_CODE (DECL_RTL (decl
)) == REG
4684 && regno_uninitialized (REGNO (DECL_RTL (decl
))))
4685 warning_with_decl (decl
,
4686 "`%s' might be used uninitialized in this function");
4687 if (TREE_CODE (decl
) == VAR_DECL
4688 && DECL_RTL (decl
) != 0
4689 && GET_CODE (DECL_RTL (decl
)) == REG
4690 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl
))))
4691 warning_with_decl (decl
,
4692 "variable `%s' might be clobbered by `longjmp' or `vfork'");
4694 for (sub
= BLOCK_SUBBLOCKS (block
); sub
; sub
= TREE_CHAIN (sub
))
4695 uninitialized_vars_warning (sub
);
4698 /* Do the appropriate part of uninitialized_vars_warning
4699 but for arguments instead of local variables. */
4702 setjmp_args_warning ()
4705 for (decl
= DECL_ARGUMENTS (current_function_decl
);
4706 decl
; decl
= TREE_CHAIN (decl
))
4707 if (DECL_RTL (decl
) != 0
4708 && GET_CODE (DECL_RTL (decl
)) == REG
4709 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl
))))
4710 warning_with_decl (decl
, "argument `%s' might be clobbered by `longjmp' or `vfork'");
4713 /* If this function call setjmp, put all vars into the stack
4714 unless they were declared `register'. */
4717 setjmp_protect (block
)
4720 register tree decl
, sub
;
4721 for (decl
= BLOCK_VARS (block
); decl
; decl
= TREE_CHAIN (decl
))
4722 if ((TREE_CODE (decl
) == VAR_DECL
4723 || TREE_CODE (decl
) == PARM_DECL
)
4724 && DECL_RTL (decl
) != 0
4725 && (GET_CODE (DECL_RTL (decl
)) == REG
4726 || (GET_CODE (DECL_RTL (decl
)) == MEM
4727 && GET_CODE (XEXP (DECL_RTL (decl
), 0)) == ADDRESSOF
))
4728 /* If this variable came from an inline function, it must be
4729 that it's life doesn't overlap the setjmp. If there was a
4730 setjmp in the function, it would already be in memory. We
4731 must exclude such variable because their DECL_RTL might be
4732 set to strange things such as virtual_stack_vars_rtx. */
4733 && ! DECL_FROM_INLINE (decl
)
4735 #ifdef NON_SAVING_SETJMP
4736 /* If longjmp doesn't restore the registers,
4737 don't put anything in them. */
4741 ! DECL_REGISTER (decl
)))
4742 put_var_into_stack (decl
);
4743 for (sub
= BLOCK_SUBBLOCKS (block
); sub
; sub
= TREE_CHAIN (sub
))
4744 setjmp_protect (sub
);
4747 /* Like the previous function, but for args instead of local variables. */
4750 setjmp_protect_args ()
4753 for (decl
= DECL_ARGUMENTS (current_function_decl
);
4754 decl
; decl
= TREE_CHAIN (decl
))
4755 if ((TREE_CODE (decl
) == VAR_DECL
4756 || TREE_CODE (decl
) == PARM_DECL
)
4757 && DECL_RTL (decl
) != 0
4758 && (GET_CODE (DECL_RTL (decl
)) == REG
4759 || (GET_CODE (DECL_RTL (decl
)) == MEM
4760 && GET_CODE (XEXP (DECL_RTL (decl
), 0)) == ADDRESSOF
))
4762 /* If longjmp doesn't restore the registers,
4763 don't put anything in them. */
4764 #ifdef NON_SAVING_SETJMP
4768 ! DECL_REGISTER (decl
)))
4769 put_var_into_stack (decl
);
4772 /* Return the context-pointer register corresponding to DECL,
4773 or 0 if it does not need one. */
4776 lookup_static_chain (decl
)
4779 tree context
= decl_function_context (decl
);
4783 || (TREE_CODE (decl
) == FUNCTION_DECL
&& DECL_NO_STATIC_CHAIN (decl
)))
4786 /* We treat inline_function_decl as an alias for the current function
4787 because that is the inline function whose vars, types, etc.
4788 are being merged into the current function.
4789 See expand_inline_function. */
4790 if (context
== current_function_decl
|| context
== inline_function_decl
)
4791 return virtual_stack_vars_rtx
;
4793 for (link
= context_display
; link
; link
= TREE_CHAIN (link
))
4794 if (TREE_PURPOSE (link
) == context
)
4795 return RTL_EXPR_RTL (TREE_VALUE (link
));
4800 /* Convert a stack slot address ADDR for variable VAR
4801 (from a containing function)
4802 into an address valid in this function (using a static chain). */
4805 fix_lexical_addr (addr
, var
)
4811 tree context
= decl_function_context (var
);
4812 struct function
*fp
;
4815 /* If this is the present function, we need not do anything. */
4816 if (context
== current_function_decl
|| context
== inline_function_decl
)
4819 for (fp
= outer_function_chain
; fp
; fp
= fp
->next
)
4820 if (fp
->decl
== context
)
4826 if (GET_CODE (addr
) == ADDRESSOF
&& GET_CODE (XEXP (addr
, 0)) == MEM
)
4827 addr
= XEXP (XEXP (addr
, 0), 0);
4829 /* Decode given address as base reg plus displacement. */
4830 if (GET_CODE (addr
) == REG
)
4831 basereg
= addr
, displacement
= 0;
4832 else if (GET_CODE (addr
) == PLUS
&& GET_CODE (XEXP (addr
, 1)) == CONST_INT
)
4833 basereg
= XEXP (addr
, 0), displacement
= INTVAL (XEXP (addr
, 1));
4837 /* We accept vars reached via the containing function's
4838 incoming arg pointer and via its stack variables pointer. */
4839 if (basereg
== fp
->internal_arg_pointer
)
4841 /* If reached via arg pointer, get the arg pointer value
4842 out of that function's stack frame.
4844 There are two cases: If a separate ap is needed, allocate a
4845 slot in the outer function for it and dereference it that way.
4846 This is correct even if the real ap is actually a pseudo.
4847 Otherwise, just adjust the offset from the frame pointer to
4850 #ifdef NEED_SEPARATE_AP
4853 if (fp
->arg_pointer_save_area
== 0)
4854 fp
->arg_pointer_save_area
4855 = assign_outer_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0, fp
);
4857 addr
= fix_lexical_addr (XEXP (fp
->arg_pointer_save_area
, 0), var
);
4858 addr
= memory_address (Pmode
, addr
);
4860 base
= copy_to_reg (gen_rtx_MEM (Pmode
, addr
));
4862 displacement
+= (FIRST_PARM_OFFSET (context
) - STARTING_FRAME_OFFSET
);
4863 base
= lookup_static_chain (var
);
4867 else if (basereg
== virtual_stack_vars_rtx
)
4869 /* This is the same code as lookup_static_chain, duplicated here to
4870 avoid an extra call to decl_function_context. */
4873 for (link
= context_display
; link
; link
= TREE_CHAIN (link
))
4874 if (TREE_PURPOSE (link
) == context
)
4876 base
= RTL_EXPR_RTL (TREE_VALUE (link
));
4884 /* Use same offset, relative to appropriate static chain or argument
4886 return plus_constant (base
, displacement
);
4889 /* Return the address of the trampoline for entering nested fn FUNCTION.
4890 If necessary, allocate a trampoline (in the stack frame)
4891 and emit rtl to initialize its contents (at entry to this function). */
4894 trampoline_address (function
)
4900 struct function
*fp
;
4903 /* Find an existing trampoline and return it. */
4904 for (link
= trampoline_list
; link
; link
= TREE_CHAIN (link
))
4905 if (TREE_PURPOSE (link
) == function
)
4907 round_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link
)), 0));
4909 for (fp
= outer_function_chain
; fp
; fp
= fp
->next
)
4910 for (link
= fp
->trampoline_list
; link
; link
= TREE_CHAIN (link
))
4911 if (TREE_PURPOSE (link
) == function
)
4913 tramp
= fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link
)), 0),
4915 return round_trampoline_addr (tramp
);
4918 /* None exists; we must make one. */
4920 /* Find the `struct function' for the function containing FUNCTION. */
4922 fn_context
= decl_function_context (function
);
4923 if (fn_context
!= current_function_decl
4924 && fn_context
!= inline_function_decl
)
4925 for (fp
= outer_function_chain
; fp
; fp
= fp
->next
)
4926 if (fp
->decl
== fn_context
)
4929 /* Allocate run-time space for this trampoline
4930 (usually in the defining function's stack frame). */
4931 #ifdef ALLOCATE_TRAMPOLINE
4932 tramp
= ALLOCATE_TRAMPOLINE (fp
);
4934 /* If rounding needed, allocate extra space
4935 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
4936 #ifdef TRAMPOLINE_ALIGNMENT
4937 #define TRAMPOLINE_REAL_SIZE \
4938 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
4940 #define TRAMPOLINE_REAL_SIZE (TRAMPOLINE_SIZE)
4943 tramp
= assign_outer_stack_local (BLKmode
, TRAMPOLINE_REAL_SIZE
, 0, fp
);
4945 tramp
= assign_stack_local (BLKmode
, TRAMPOLINE_REAL_SIZE
, 0);
4948 /* Record the trampoline for reuse and note it for later initialization
4949 by expand_function_end. */
4952 push_obstacks (fp
->function_maybepermanent_obstack
,
4953 fp
->function_maybepermanent_obstack
);
4954 rtlexp
= make_node (RTL_EXPR
);
4955 RTL_EXPR_RTL (rtlexp
) = tramp
;
4956 fp
->trampoline_list
= tree_cons (function
, rtlexp
, fp
->trampoline_list
);
4961 /* Make the RTL_EXPR node temporary, not momentary, so that the
4962 trampoline_list doesn't become garbage. */
4963 int momentary
= suspend_momentary ();
4964 rtlexp
= make_node (RTL_EXPR
);
4965 resume_momentary (momentary
);
4967 RTL_EXPR_RTL (rtlexp
) = tramp
;
4968 trampoline_list
= tree_cons (function
, rtlexp
, trampoline_list
);
4971 tramp
= fix_lexical_addr (XEXP (tramp
, 0), function
);
4972 return round_trampoline_addr (tramp
);
4975 /* Given a trampoline address,
4976 round it to multiple of TRAMPOLINE_ALIGNMENT. */
4979 round_trampoline_addr (tramp
)
4982 #ifdef TRAMPOLINE_ALIGNMENT
4983 /* Round address up to desired boundary. */
4984 rtx temp
= gen_reg_rtx (Pmode
);
4985 temp
= expand_binop (Pmode
, add_optab
, tramp
,
4986 GEN_INT (TRAMPOLINE_ALIGNMENT
/ BITS_PER_UNIT
- 1),
4987 temp
, 0, OPTAB_LIB_WIDEN
);
4988 tramp
= expand_binop (Pmode
, and_optab
, temp
,
4989 GEN_INT (- TRAMPOLINE_ALIGNMENT
/ BITS_PER_UNIT
),
4990 temp
, 0, OPTAB_LIB_WIDEN
);
4995 /* The functions identify_blocks and reorder_blocks provide a way to
4996 reorder the tree of BLOCK nodes, for optimizers that reshuffle or
4997 duplicate portions of the RTL code. Call identify_blocks before
4998 changing the RTL, and call reorder_blocks after. */
5000 /* Put all this function's BLOCK nodes including those that are chained
5001 onto the first block into a vector, and return it.
5002 Also store in each NOTE for the beginning or end of a block
5003 the index of that block in the vector.
5004 The arguments are BLOCK, the chain of top-level blocks of the function,
5005 and INSNS, the insn chain of the function. */
5008 identify_blocks (block
, insns
)
5016 int next_block_number
= 1;
5017 int current_block_number
= 1;
5023 n_blocks
= all_blocks (block
, 0);
5024 block_vector
= (tree
*) xmalloc (n_blocks
* sizeof (tree
));
5025 block_stack
= (int *) alloca (n_blocks
* sizeof (int));
5027 all_blocks (block
, block_vector
);
5029 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
5030 if (GET_CODE (insn
) == NOTE
)
5032 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_BEG
)
5034 block_stack
[depth
++] = current_block_number
;
5035 current_block_number
= next_block_number
;
5036 NOTE_BLOCK_NUMBER (insn
) = next_block_number
++;
5038 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_END
)
5040 current_block_number
= block_stack
[--depth
];
5041 NOTE_BLOCK_NUMBER (insn
) = current_block_number
;
5045 if (n_blocks
!= next_block_number
)
5048 return block_vector
;
5051 /* Given BLOCK_VECTOR which was returned by identify_blocks,
5052 and a revised instruction chain, rebuild the tree structure
5053 of BLOCK nodes to correspond to the new order of RTL.
5054 The new block tree is inserted below TOP_BLOCK.
5055 Returns the current top-level block. */
5058 reorder_blocks (block_vector
, block
, insns
)
5063 tree current_block
= block
;
5066 if (block_vector
== 0)
5069 /* Prune the old trees away, so that it doesn't get in the way. */
5070 BLOCK_SUBBLOCKS (current_block
) = 0;
5071 BLOCK_CHAIN (current_block
) = 0;
5073 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
5074 if (GET_CODE (insn
) == NOTE
)
5076 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_BEG
)
5078 tree block
= block_vector
[NOTE_BLOCK_NUMBER (insn
)];
5079 /* If we have seen this block before, copy it. */
5080 if (TREE_ASM_WRITTEN (block
))
5081 block
= copy_node (block
);
5082 BLOCK_SUBBLOCKS (block
) = 0;
5083 TREE_ASM_WRITTEN (block
) = 1;
5084 BLOCK_SUPERCONTEXT (block
) = current_block
;
5085 BLOCK_CHAIN (block
) = BLOCK_SUBBLOCKS (current_block
);
5086 BLOCK_SUBBLOCKS (current_block
) = block
;
5087 current_block
= block
;
5088 NOTE_SOURCE_FILE (insn
) = 0;
5090 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_END
)
5092 BLOCK_SUBBLOCKS (current_block
)
5093 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block
));
5094 current_block
= BLOCK_SUPERCONTEXT (current_block
);
5095 NOTE_SOURCE_FILE (insn
) = 0;
5099 BLOCK_SUBBLOCKS (current_block
)
5100 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block
));
5101 return current_block
;
5104 /* Reverse the order of elements in the chain T of blocks,
5105 and return the new head of the chain (old last element). */
5111 register tree prev
= 0, decl
, next
;
5112 for (decl
= t
; decl
; decl
= next
)
5114 next
= BLOCK_CHAIN (decl
);
5115 BLOCK_CHAIN (decl
) = prev
;
5121 /* Count the subblocks of the list starting with BLOCK, and list them
5122 all into the vector VECTOR. Also clear TREE_ASM_WRITTEN in all
5126 all_blocks (block
, vector
)
5134 TREE_ASM_WRITTEN (block
) = 0;
5136 /* Record this block. */
5138 vector
[n_blocks
] = block
;
5142 /* Record the subblocks, and their subblocks... */
5143 n_blocks
+= all_blocks (BLOCK_SUBBLOCKS (block
),
5144 vector
? vector
+ n_blocks
: 0);
5145 block
= BLOCK_CHAIN (block
);
5151 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
5152 and initialize static variables for generating RTL for the statements
5156 init_function_start (subr
, filename
, line
)
5161 init_stmt_for_function ();
5163 cse_not_expected
= ! optimize
;
5165 /* Caller save not needed yet. */
5166 caller_save_needed
= 0;
5168 /* No stack slots have been made yet. */
5169 stack_slot_list
= 0;
5171 /* There is no stack slot for handling nonlocal gotos. */
5172 nonlocal_goto_handler_slot
= 0;
5173 nonlocal_goto_stack_level
= 0;
5175 /* No labels have been declared for nonlocal use. */
5176 nonlocal_labels
= 0;
5178 /* No function calls so far in this function. */
5179 function_call_count
= 0;
5181 /* No parm regs have been allocated.
5182 (This is important for output_inline_function.) */
5183 max_parm_reg
= LAST_VIRTUAL_REGISTER
+ 1;
5185 /* Initialize the RTL mechanism. */
5188 /* Initialize the queue of pending postincrement and postdecrements,
5189 and some other info in expr.c. */
5192 /* We haven't done register allocation yet. */
5195 init_const_rtx_hash_table ();
5197 current_function_name
= (*decl_printable_name
) (subr
, 2);
5199 /* Nonzero if this is a nested function that uses a static chain. */
5201 current_function_needs_context
5202 = (decl_function_context (current_function_decl
) != 0
5203 && ! DECL_NO_STATIC_CHAIN (current_function_decl
));
5205 /* Set if a call to setjmp is seen. */
5206 current_function_calls_setjmp
= 0;
5208 /* Set if a call to longjmp is seen. */
5209 current_function_calls_longjmp
= 0;
5211 current_function_calls_alloca
= 0;
5212 current_function_has_nonlocal_label
= 0;
5213 current_function_has_nonlocal_goto
= 0;
5214 current_function_contains_functions
= 0;
5215 current_function_is_thunk
= 0;
5217 current_function_returns_pcc_struct
= 0;
5218 current_function_returns_struct
= 0;
5219 current_function_epilogue_delay_list
= 0;
5220 current_function_uses_const_pool
= 0;
5221 current_function_uses_pic_offset_table
= 0;
5223 /* We have not yet needed to make a label to jump to for tail-recursion. */
5224 tail_recursion_label
= 0;
5226 /* We haven't had a need to make a save area for ap yet. */
5228 arg_pointer_save_area
= 0;
5230 /* No stack slots allocated yet. */
5233 /* No SAVE_EXPRs in this function yet. */
5236 /* No RTL_EXPRs in this function yet. */
5239 /* Set up to allocate temporaries. */
5242 /* Within function body, compute a type's size as soon it is laid out. */
5243 immediate_size_expand
++;
5245 /* We haven't made any trampolines for this function yet. */
5246 trampoline_list
= 0;
5248 init_pending_stack_adjust ();
5249 inhibit_defer_pop
= 0;
5251 current_function_outgoing_args_size
= 0;
5253 /* Prevent ever trying to delete the first instruction of a function.
5254 Also tell final how to output a linenum before the function prologue. */
5255 emit_line_note (filename
, line
);
5257 /* Make sure first insn is a note even if we don't want linenums.
5258 This makes sure the first insn will never be deleted.
5259 Also, final expects a note to appear there. */
5260 emit_note (NULL_PTR
, NOTE_INSN_DELETED
);
5262 /* Set flags used by final.c. */
5263 if (aggregate_value_p (DECL_RESULT (subr
)))
5265 #ifdef PCC_STATIC_STRUCT_RETURN
5266 current_function_returns_pcc_struct
= 1;
5268 current_function_returns_struct
= 1;
5271 /* Warn if this value is an aggregate type,
5272 regardless of which calling convention we are using for it. */
5273 if (warn_aggregate_return
5274 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr
))))
5275 warning ("function returns an aggregate");
5277 current_function_returns_pointer
5278 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr
)));
5280 /* Indicate that we need to distinguish between the return value of the
5281 present function and the return value of a function being called. */
5282 rtx_equal_function_value_matters
= 1;
5284 /* Indicate that we have not instantiated virtual registers yet. */
5285 virtuals_instantiated
= 0;
5287 /* Indicate we have no need of a frame pointer yet. */
5288 frame_pointer_needed
= 0;
5290 /* By default assume not varargs or stdarg. */
5291 current_function_varargs
= 0;
5292 current_function_stdarg
= 0;
5295 /* Indicate that the current function uses extra args
5296 not explicitly mentioned in the argument list in any fashion. */
5301 current_function_varargs
= 1;
5304 /* Expand a call to __main at the beginning of a possible main function. */
5306 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
5307 #undef HAS_INIT_SECTION
5308 #define HAS_INIT_SECTION
5312 expand_main_function ()
5314 #if !defined (HAS_INIT_SECTION)
5315 emit_library_call (gen_rtx_SYMBOL_REF (Pmode
, NAME__MAIN
), 0,
5317 #endif /* not HAS_INIT_SECTION */
5320 extern struct obstack permanent_obstack
;
5322 /* Start the RTL for a new function, and set variables used for
5324 SUBR is the FUNCTION_DECL node.
5325 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
5326 the function's parameters, which must be run at any return statement. */
5329 expand_function_start (subr
, parms_have_cleanups
)
5331 int parms_have_cleanups
;
5337 /* Make sure volatile mem refs aren't considered
5338 valid operands of arithmetic insns. */
5339 init_recog_no_volatile ();
5341 /* If function gets a static chain arg, store it in the stack frame.
5342 Do this first, so it gets the first stack slot offset. */
5343 if (current_function_needs_context
)
5345 last_ptr
= assign_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0);
5347 /* Delay copying static chain if it is not a register to avoid
5348 conflicts with regs used for parameters. */
5349 if (! SMALL_REGISTER_CLASSES
5350 || GET_CODE (static_chain_incoming_rtx
) == REG
)
5351 emit_move_insn (last_ptr
, static_chain_incoming_rtx
);
5354 /* If the parameters of this function need cleaning up, get a label
5355 for the beginning of the code which executes those cleanups. This must
5356 be done before doing anything with return_label. */
5357 if (parms_have_cleanups
)
5358 cleanup_label
= gen_label_rtx ();
5362 /* Make the label for return statements to jump to, if this machine
5363 does not have a one-instruction return and uses an epilogue,
5364 or if it returns a structure, or if it has parm cleanups. */
5366 if (cleanup_label
== 0 && HAVE_return
5367 && ! current_function_returns_pcc_struct
5368 && ! (current_function_returns_struct
&& ! optimize
))
5371 return_label
= gen_label_rtx ();
5373 return_label
= gen_label_rtx ();
5376 /* Initialize rtx used to return the value. */
5377 /* Do this before assign_parms so that we copy the struct value address
5378 before any library calls that assign parms might generate. */
5380 /* Decide whether to return the value in memory or in a register. */
5381 if (aggregate_value_p (DECL_RESULT (subr
)))
5383 /* Returning something that won't go in a register. */
5384 register rtx value_address
= 0;
5386 #ifdef PCC_STATIC_STRUCT_RETURN
5387 if (current_function_returns_pcc_struct
)
5389 int size
= int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr
)));
5390 value_address
= assemble_static_space (size
);
5395 /* Expect to be passed the address of a place to store the value.
5396 If it is passed as an argument, assign_parms will take care of
5398 if (struct_value_incoming_rtx
)
5400 value_address
= gen_reg_rtx (Pmode
);
5401 emit_move_insn (value_address
, struct_value_incoming_rtx
);
5406 DECL_RTL (DECL_RESULT (subr
))
5407 = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr
)), value_address
);
5408 MEM_IN_STRUCT_P (DECL_RTL (DECL_RESULT (subr
)))
5409 = AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr
)));
5412 else if (DECL_MODE (DECL_RESULT (subr
)) == VOIDmode
)
5413 /* If return mode is void, this decl rtl should not be used. */
5414 DECL_RTL (DECL_RESULT (subr
)) = 0;
5415 else if (parms_have_cleanups
)
5417 /* If function will end with cleanup code for parms,
5418 compute the return values into a pseudo reg,
5419 which we will copy into the true return register
5420 after the cleanups are done. */
5422 enum machine_mode mode
= DECL_MODE (DECL_RESULT (subr
));
5424 #ifdef PROMOTE_FUNCTION_RETURN
5425 tree type
= TREE_TYPE (DECL_RESULT (subr
));
5426 int unsignedp
= TREE_UNSIGNED (type
);
5428 mode
= promote_mode (type
, mode
, &unsignedp
, 1);
5431 DECL_RTL (DECL_RESULT (subr
)) = gen_reg_rtx (mode
);
5434 /* Scalar, returned in a register. */
5436 #ifdef FUNCTION_OUTGOING_VALUE
5437 DECL_RTL (DECL_RESULT (subr
))
5438 = FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (subr
)), subr
);
5440 DECL_RTL (DECL_RESULT (subr
))
5441 = FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (subr
)), subr
);
5444 /* Mark this reg as the function's return value. */
5445 if (GET_CODE (DECL_RTL (DECL_RESULT (subr
))) == REG
)
5447 REG_FUNCTION_VALUE_P (DECL_RTL (DECL_RESULT (subr
))) = 1;
5448 /* Needed because we may need to move this to memory
5449 in case it's a named return value whose address is taken. */
5450 DECL_REGISTER (DECL_RESULT (subr
)) = 1;
5454 /* Initialize rtx for parameters and local variables.
5455 In some cases this requires emitting insns. */
5457 assign_parms (subr
, 0);
5459 /* Copy the static chain now if it wasn't a register. The delay is to
5460 avoid conflicts with the parameter passing registers. */
5462 if (SMALL_REGISTER_CLASSES
&& current_function_needs_context
)
5463 if (GET_CODE (static_chain_incoming_rtx
) != REG
)
5464 emit_move_insn (last_ptr
, static_chain_incoming_rtx
);
5466 /* The following was moved from init_function_start.
5467 The move is supposed to make sdb output more accurate. */
5468 /* Indicate the beginning of the function body,
5469 as opposed to parm setup. */
5470 emit_note (NULL_PTR
, NOTE_INSN_FUNCTION_BEG
);
5472 /* If doing stupid allocation, mark parms as born here. */
5474 if (GET_CODE (get_last_insn ()) != NOTE
)
5475 emit_note (NULL_PTR
, NOTE_INSN_DELETED
);
5476 parm_birth_insn
= get_last_insn ();
5480 for (i
= LAST_VIRTUAL_REGISTER
+ 1; i
< max_parm_reg
; i
++)
5481 use_variable (regno_reg_rtx
[i
]);
5483 if (current_function_internal_arg_pointer
!= virtual_incoming_args_rtx
)
5484 use_variable (current_function_internal_arg_pointer
);
5487 context_display
= 0;
5488 if (current_function_needs_context
)
5490 /* Fetch static chain values for containing functions. */
5491 tem
= decl_function_context (current_function_decl
);
5492 /* If not doing stupid register allocation copy the static chain
5493 pointer into a pseudo. If we have small register classes, copy
5494 the value from memory if static_chain_incoming_rtx is a REG. If
5495 we do stupid register allocation, we use the stack address
5497 if (tem
&& ! obey_regdecls
)
5499 /* If the static chain originally came in a register, put it back
5500 there, then move it out in the next insn. The reason for
5501 this peculiar code is to satisfy function integration. */
5502 if (SMALL_REGISTER_CLASSES
5503 && GET_CODE (static_chain_incoming_rtx
) == REG
)
5504 emit_move_insn (static_chain_incoming_rtx
, last_ptr
);
5505 last_ptr
= copy_to_reg (static_chain_incoming_rtx
);
5510 tree rtlexp
= make_node (RTL_EXPR
);
5512 RTL_EXPR_RTL (rtlexp
) = last_ptr
;
5513 context_display
= tree_cons (tem
, rtlexp
, context_display
);
5514 tem
= decl_function_context (tem
);
5517 /* Chain thru stack frames, assuming pointer to next lexical frame
5518 is found at the place we always store it. */
5519 #ifdef FRAME_GROWS_DOWNWARD
5520 last_ptr
= plus_constant (last_ptr
, - GET_MODE_SIZE (Pmode
));
5522 last_ptr
= copy_to_reg (gen_rtx_MEM (Pmode
,
5523 memory_address (Pmode
, last_ptr
)));
5525 /* If we are not optimizing, ensure that we know that this
5526 piece of context is live over the entire function. */
5528 save_expr_regs
= gen_rtx_EXPR_LIST (VOIDmode
, last_ptr
,
5533 /* After the display initializations is where the tail-recursion label
5534 should go, if we end up needing one. Ensure we have a NOTE here
5535 since some things (like trampolines) get placed before this. */
5536 tail_recursion_reentry
= emit_note (NULL_PTR
, NOTE_INSN_DELETED
);
5538 /* Evaluate now the sizes of any types declared among the arguments. */
5539 for (tem
= nreverse (get_pending_sizes ()); tem
; tem
= TREE_CHAIN (tem
))
5541 expand_expr (TREE_VALUE (tem
), const0_rtx
, VOIDmode
,
5542 EXPAND_MEMORY_USE_BAD
);
5543 /* Flush the queue in case this parameter declaration has
5548 /* Make sure there is a line number after the function entry setup code. */
5549 force_next_line_note ();
5552 /* Generate RTL for the end of the current function.
5553 FILENAME and LINE are the current position in the source file.
5555 It is up to language-specific callers to do cleanups for parameters--
5556 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
5559 expand_function_end (filename
, line
, end_bindings
)
5567 #ifdef TRAMPOLINE_TEMPLATE
5568 static rtx initial_trampoline
;
5571 #ifdef NON_SAVING_SETJMP
5572 /* Don't put any variables in registers if we call setjmp
5573 on a machine that fails to restore the registers. */
5574 if (NON_SAVING_SETJMP
&& current_function_calls_setjmp
)
5576 if (DECL_INITIAL (current_function_decl
) != error_mark_node
)
5577 setjmp_protect (DECL_INITIAL (current_function_decl
));
5579 setjmp_protect_args ();
5583 /* Save the argument pointer if a save area was made for it. */
5584 if (arg_pointer_save_area
)
5586 rtx x
= gen_move_insn (arg_pointer_save_area
, virtual_incoming_args_rtx
);
5587 emit_insn_before (x
, tail_recursion_reentry
);
5590 /* Initialize any trampolines required by this function. */
5591 for (link
= trampoline_list
; link
; link
= TREE_CHAIN (link
))
5593 tree function
= TREE_PURPOSE (link
);
5594 rtx context
= lookup_static_chain (function
);
5595 rtx tramp
= RTL_EXPR_RTL (TREE_VALUE (link
));
5599 #ifdef TRAMPOLINE_TEMPLATE
5600 /* First make sure this compilation has a template for
5601 initializing trampolines. */
5602 if (initial_trampoline
== 0)
5604 end_temporary_allocation ();
5606 = gen_rtx_MEM (BLKmode
, assemble_trampoline_template ());
5607 resume_temporary_allocation ();
5611 /* Generate insns to initialize the trampoline. */
5613 tramp
= round_trampoline_addr (XEXP (tramp
, 0));
5614 #ifdef TRAMPOLINE_TEMPLATE
5615 blktramp
= change_address (initial_trampoline
, BLKmode
, tramp
);
5616 emit_block_move (blktramp
, initial_trampoline
,
5617 GEN_INT (TRAMPOLINE_SIZE
),
5618 TRAMPOLINE_ALIGNMENT
/ BITS_PER_UNIT
);
5620 INITIALIZE_TRAMPOLINE (tramp
, XEXP (DECL_RTL (function
), 0), context
);
5624 /* Put those insns at entry to the containing function (this one). */
5625 emit_insns_before (seq
, tail_recursion_reentry
);
5628 /* If we are doing stack checking and this function makes calls,
5629 do a stack probe at the start of the function to ensure we have enough
5630 space for another stack frame. */
5631 if (flag_stack_check
&& ! STACK_CHECK_BUILTIN
)
5635 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
5636 if (GET_CODE (insn
) == CALL_INSN
)
5639 probe_stack_range (STACK_CHECK_PROTECT
,
5640 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE
));
5643 emit_insns_before (seq
, tail_recursion_reentry
);
5648 /* Warn about unused parms if extra warnings were specified. */
5649 if (warn_unused
&& extra_warnings
)
5653 for (decl
= DECL_ARGUMENTS (current_function_decl
);
5654 decl
; decl
= TREE_CHAIN (decl
))
5655 if (! TREE_USED (decl
) && TREE_CODE (decl
) == PARM_DECL
5656 && DECL_NAME (decl
) && ! DECL_ARTIFICIAL (decl
))
5657 warning_with_decl (decl
, "unused parameter `%s'");
5660 /* Delete handlers for nonlocal gotos if nothing uses them. */
5661 if (nonlocal_goto_handler_slot
!= 0 && !current_function_has_nonlocal_label
)
5664 /* End any sequences that failed to be closed due to syntax errors. */
5665 while (in_sequence_p ())
5668 /* Outside function body, can't compute type's actual size
5669 until next function's body starts. */
5670 immediate_size_expand
--;
5672 /* If doing stupid register allocation,
5673 mark register parms as dying here. */
5678 for (i
= LAST_VIRTUAL_REGISTER
+ 1; i
< max_parm_reg
; i
++)
5679 use_variable (regno_reg_rtx
[i
]);
5681 /* Likewise for the regs of all the SAVE_EXPRs in the function. */
5683 for (tem
= save_expr_regs
; tem
; tem
= XEXP (tem
, 1))
5685 use_variable (XEXP (tem
, 0));
5686 use_variable_after (XEXP (tem
, 0), parm_birth_insn
);
5689 if (current_function_internal_arg_pointer
!= virtual_incoming_args_rtx
)
5690 use_variable (current_function_internal_arg_pointer
);
5693 clear_pending_stack_adjust ();
5694 do_pending_stack_adjust ();
5696 /* Mark the end of the function body.
5697 If control reaches this insn, the function can drop through
5698 without returning a value. */
5699 emit_note (NULL_PTR
, NOTE_INSN_FUNCTION_END
);
5701 /* Must mark the last line number note in the function, so that the test
5702 coverage code can avoid counting the last line twice. This just tells
5703 the code to ignore the immediately following line note, since there
5704 already exists a copy of this note somewhere above. This line number
5705 note is still needed for debugging though, so we can't delete it. */
5706 if (flag_test_coverage
)
5707 emit_note (NULL_PTR
, NOTE_REPEATED_LINE_NUMBER
);
5709 /* Output a linenumber for the end of the function.
5710 SDB depends on this. */
5711 emit_line_note_force (filename
, line
);
5713 /* Output the label for the actual return from the function,
5714 if one is expected. This happens either because a function epilogue
5715 is used instead of a return instruction, or because a return was done
5716 with a goto in order to run local cleanups, or because of pcc-style
5717 structure returning. */
5720 emit_label (return_label
);
5722 /* C++ uses this. */
5724 expand_end_bindings (0, 0, 0);
5726 /* Now handle any leftover exception regions that may have been
5727 created for the parameters. */
5729 rtx last
= get_last_insn ();
5732 expand_leftover_cleanups ();
5734 /* If the above emitted any code, may sure we jump around it. */
5735 if (last
!= get_last_insn ())
5737 label
= gen_label_rtx ();
5738 last
= emit_jump_insn_after (gen_jump (label
), last
);
5739 last
= emit_barrier_after (last
);
5744 /* If we had calls to alloca, and this machine needs
5745 an accurate stack pointer to exit the function,
5746 insert some code to save and restore the stack pointer. */
5747 #ifdef EXIT_IGNORE_STACK
5748 if (! EXIT_IGNORE_STACK
)
5750 if (current_function_calls_alloca
)
5754 emit_stack_save (SAVE_FUNCTION
, &tem
, parm_birth_insn
);
5755 emit_stack_restore (SAVE_FUNCTION
, tem
, NULL_RTX
);
5758 /* If scalar return value was computed in a pseudo-reg,
5759 copy that to the hard return register. */
5760 if (DECL_RTL (DECL_RESULT (current_function_decl
)) != 0
5761 && GET_CODE (DECL_RTL (DECL_RESULT (current_function_decl
))) == REG
5762 && (REGNO (DECL_RTL (DECL_RESULT (current_function_decl
)))
5763 >= FIRST_PSEUDO_REGISTER
))
5765 rtx real_decl_result
;
5767 #ifdef FUNCTION_OUTGOING_VALUE
5769 = FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl
)),
5770 current_function_decl
);
5773 = FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl
)),
5774 current_function_decl
);
5776 REG_FUNCTION_VALUE_P (real_decl_result
) = 1;
5777 /* If this is a BLKmode structure being returned in registers, then use
5778 the mode computed in expand_return. */
5779 if (GET_MODE (real_decl_result
) == BLKmode
)
5780 PUT_MODE (real_decl_result
,
5781 GET_MODE (DECL_RTL (DECL_RESULT (current_function_decl
))));
5782 emit_move_insn (real_decl_result
,
5783 DECL_RTL (DECL_RESULT (current_function_decl
)));
5784 emit_insn (gen_rtx_USE (VOIDmode
, real_decl_result
));
5786 /* The delay slot scheduler assumes that current_function_return_rtx
5787 holds the hard register containing the return value, not a temporary
5789 current_function_return_rtx
= real_decl_result
;
5792 /* If returning a structure, arrange to return the address of the value
5793 in a place where debuggers expect to find it.
5795 If returning a structure PCC style,
5796 the caller also depends on this value.
5797 And current_function_returns_pcc_struct is not necessarily set. */
5798 if (current_function_returns_struct
5799 || current_function_returns_pcc_struct
)
5801 rtx value_address
= XEXP (DECL_RTL (DECL_RESULT (current_function_decl
)), 0);
5802 tree type
= TREE_TYPE (DECL_RESULT (current_function_decl
));
5803 #ifdef FUNCTION_OUTGOING_VALUE
5805 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type
),
5806 current_function_decl
);
5809 = FUNCTION_VALUE (build_pointer_type (type
),
5810 current_function_decl
);
5813 /* Mark this as a function return value so integrate will delete the
5814 assignment and USE below when inlining this function. */
5815 REG_FUNCTION_VALUE_P (outgoing
) = 1;
5817 emit_move_insn (outgoing
, value_address
);
5818 use_variable (outgoing
);
5821 /* Output a return insn if we are using one.
5822 Otherwise, let the rtl chain end here, to drop through
5823 into the epilogue. */
5828 emit_jump_insn (gen_return ());
5833 /* Fix up any gotos that jumped out to the outermost
5834 binding level of the function.
5835 Must follow emitting RETURN_LABEL. */
5837 /* If you have any cleanups to do at this point,
5838 and they need to create temporary variables,
5839 then you will lose. */
5840 expand_fixups (get_insns ());
5843 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
5845 static int *prologue
;
5846 static int *epilogue
;
5848 /* Create an array that records the INSN_UIDs of INSNS (either a sequence
5849 or a single insn). */
5852 record_insns (insns
)
5857 if (GET_CODE (insns
) == SEQUENCE
)
5859 int len
= XVECLEN (insns
, 0);
5860 vec
= (int *) oballoc ((len
+ 1) * sizeof (int));
5863 vec
[len
] = INSN_UID (XVECEXP (insns
, 0, len
));
5867 vec
= (int *) oballoc (2 * sizeof (int));
5868 vec
[0] = INSN_UID (insns
);
5874 /* Determine how many INSN_UIDs in VEC are part of INSN. */
5876 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
5878 contains (insn
, vec
)
5884 if (GET_CODE (insn
) == INSN
5885 && GET_CODE (PATTERN (insn
)) == SEQUENCE
)
5888 for (i
= XVECLEN (PATTERN (insn
), 0) - 1; i
>= 0; i
--)
5889 for (j
= 0; vec
[j
]; j
++)
5890 if (INSN_UID (XVECEXP (PATTERN (insn
), 0, i
)) == vec
[j
])
5896 for (j
= 0; vec
[j
]; j
++)
5897 if (INSN_UID (insn
) == vec
[j
])
5902 #endif /* HAVE_prologue || HAVE_epilogue */
5904 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
5905 this into place with notes indicating where the prologue ends and where
5906 the epilogue begins. Update the basic block information when possible. */
5909 thread_prologue_and_epilogue_insns (f
)
5912 #ifdef HAVE_prologue
5917 /* The first insn (a NOTE_INSN_DELETED) is followed by zero or more
5918 prologue insns and a NOTE_INSN_PROLOGUE_END. */
5919 emit_note_after (NOTE_INSN_PROLOGUE_END
, f
);
5920 seq
= gen_prologue ();
5921 head
= emit_insn_after (seq
, f
);
5923 /* Include the new prologue insns in the first block. Ignore them
5924 if they form a basic block unto themselves. */
5925 if (basic_block_head
&& n_basic_blocks
5926 && GET_CODE (basic_block_head
[0]) != CODE_LABEL
)
5927 basic_block_head
[0] = NEXT_INSN (f
);
5929 /* Retain a map of the prologue insns. */
5930 prologue
= record_insns (GET_CODE (seq
) == SEQUENCE
? seq
: head
);
5936 #ifdef HAVE_epilogue
5939 rtx insn
= get_last_insn ();
5940 rtx prev
= prev_nonnote_insn (insn
);
5942 /* If we end with a BARRIER, we don't need an epilogue. */
5943 if (! (prev
&& GET_CODE (prev
) == BARRIER
))
5949 /* The last basic block ends with a NOTE_INSN_EPILOGUE_BEG, the
5950 epilogue insns, the USE insns at the end of a function,
5951 the jump insn that returns, and then a BARRIER. */
5953 /* Move the USE insns at the end of a function onto a list. */
5955 && GET_CODE (prev
) == INSN
5956 && GET_CODE (PATTERN (prev
)) == USE
)
5959 prev
= prev_nonnote_insn (prev
);
5961 NEXT_INSN (PREV_INSN (tem
)) = NEXT_INSN (tem
);
5962 PREV_INSN (NEXT_INSN (tem
)) = PREV_INSN (tem
);
5965 NEXT_INSN (tem
) = first_use
;
5966 PREV_INSN (first_use
) = tem
;
5973 emit_barrier_after (insn
);
5975 seq
= gen_epilogue ();
5976 tail
= emit_jump_insn_after (seq
, insn
);
5978 /* Insert the USE insns immediately before the return insn, which
5979 must be the first instruction before the final barrier. */
5982 tem
= prev_nonnote_insn (get_last_insn ());
5983 NEXT_INSN (PREV_INSN (tem
)) = first_use
;
5984 PREV_INSN (first_use
) = PREV_INSN (tem
);
5985 PREV_INSN (tem
) = last_use
;
5986 NEXT_INSN (last_use
) = tem
;
5989 emit_note_after (NOTE_INSN_EPILOGUE_BEG
, insn
);
5991 /* Include the new epilogue insns in the last block. Ignore
5992 them if they form a basic block unto themselves. */
5993 if (basic_block_end
&& n_basic_blocks
5994 && GET_CODE (basic_block_end
[n_basic_blocks
- 1]) != JUMP_INSN
)
5995 basic_block_end
[n_basic_blocks
- 1] = tail
;
5997 /* Retain a map of the epilogue insns. */
5998 epilogue
= record_insns (GET_CODE (seq
) == SEQUENCE
? seq
: tail
);
6006 /* Reposition the prologue-end and epilogue-begin notes after instruction
6007 scheduling and delayed branch scheduling. */
6010 reposition_prologue_and_epilogue_notes (f
)
6013 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
6014 /* Reposition the prologue and epilogue notes. */
6022 register rtx insn
, note
= 0;
6024 /* Scan from the beginning until we reach the last prologue insn.
6025 We apparently can't depend on basic_block_{head,end} after
6027 for (len
= 0; prologue
[len
]; len
++)
6029 for (insn
= f
; len
&& insn
; insn
= NEXT_INSN (insn
))
6031 if (GET_CODE (insn
) == NOTE
)
6033 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_PROLOGUE_END
)
6036 else if ((len
-= contains (insn
, prologue
)) == 0)
6038 /* Find the prologue-end note if we haven't already, and
6039 move it to just after the last prologue insn. */
6042 for (note
= insn
; (note
= NEXT_INSN (note
));)
6043 if (GET_CODE (note
) == NOTE
6044 && NOTE_LINE_NUMBER (note
) == NOTE_INSN_PROLOGUE_END
)
6047 next
= NEXT_INSN (note
);
6048 prev
= PREV_INSN (note
);
6050 NEXT_INSN (prev
) = next
;
6052 PREV_INSN (next
) = prev
;
6053 add_insn_after (note
, insn
);
6060 register rtx insn
, note
= 0;
6062 /* Scan from the end until we reach the first epilogue insn.
6063 We apparently can't depend on basic_block_{head,end} after
6065 for (len
= 0; epilogue
[len
]; len
++)
6067 for (insn
= get_last_insn (); len
&& insn
; insn
= PREV_INSN (insn
))
6069 if (GET_CODE (insn
) == NOTE
)
6071 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_EPILOGUE_BEG
)
6074 else if ((len
-= contains (insn
, epilogue
)) == 0)
6076 /* Find the epilogue-begin note if we haven't already, and
6077 move it to just before the first epilogue insn. */
6080 for (note
= insn
; (note
= PREV_INSN (note
));)
6081 if (GET_CODE (note
) == NOTE
6082 && NOTE_LINE_NUMBER (note
) == NOTE_INSN_EPILOGUE_BEG
)
6085 next
= NEXT_INSN (note
);
6086 prev
= PREV_INSN (note
);
6088 NEXT_INSN (prev
) = next
;
6090 PREV_INSN (next
) = prev
;
6091 add_insn_after (note
, PREV_INSN (insn
));
6096 #endif /* HAVE_prologue or HAVE_epilogue */