1 /* Expands front end tree to back end RTL for GNU C-Compiler
2 Copyright (C) 1987, 88, 89, 91-98, 1999 Free Software Foundation, Inc.
4 This file is part of GNU CC.
6 GNU CC is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 GNU CC is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GNU CC; see the file COPYING. If not, write to
18 the Free Software Foundation, 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
22 /* This file handles the generation of rtl code from tree structure
23 at the level of the function as a whole.
24 It creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 `expand_function_start' is called at the beginning of a function,
28 before the function body is parsed, and `expand_function_end' is
29 called after parsing the body.
31 Call `assign_stack_local' to allocate a stack slot for a local variable.
32 This is usually done during the RTL generation for the function body,
33 but it can also be done in the reload pass when a pseudo-register does
34 not get a hard register.
36 Call `put_var_into_stack' when you learn, belatedly, that a variable
37 previously given a pseudo-register must in fact go in the stack.
38 This function changes the DECL_RTL to be a stack slot instead of a reg
39 then scans all the RTL instructions so far generated to correct them. */
48 #include "insn-flags.h"
50 #include "insn-codes.h"
52 #include "hard-reg-set.h"
53 #include "insn-config.h"
56 #include "basic-block.h"
60 #if !defined PREFERRED_STACK_BOUNDARY && defined STACK_BOUNDARY
61 #define PREFERRED_STACK_BOUNDARY STACK_BOUNDARY
64 #ifndef TRAMPOLINE_ALIGNMENT
65 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
68 /* Some systems use __main in a way incompatible with its use in gcc, in these
69 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
70 give the same symbol without quotes for an alternative entry point. You
71 must define both, or neither. */
73 #define NAME__MAIN "__main"
74 #define SYMBOL__MAIN __main
77 /* Round a value to the lowest integer less than it that is a multiple of
78 the required alignment. Avoid using division in case the value is
79 negative. Assume the alignment is a power of two. */
80 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
82 /* Similar, but round to the next highest integer that meets the
84 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
86 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
87 during rtl generation. If they are different register numbers, this is
88 always true. It may also be true if
89 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
90 generation. See fix_lexical_addr for details. */
92 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
93 #define NEED_SEPARATE_AP
96 /* Number of bytes of args popped by function being compiled on its return.
97 Zero if no bytes are to be popped.
98 May affect compilation of return insn or of function epilogue. */
100 int current_function_pops_args;
102 /* Nonzero if function being compiled needs to be given an address
103 where the value should be stored. */
105 int current_function_returns_struct;
107 /* Nonzero if function being compiled needs to
108 return the address of where it has put a structure value. */
110 int current_function_returns_pcc_struct;
112 /* Nonzero if function being compiled needs to be passed a static chain. */
114 int current_function_needs_context;
116 /* Nonzero if function being compiled can call setjmp. */
118 int current_function_calls_setjmp;
120 /* Nonzero if function being compiled can call longjmp. */
122 int current_function_calls_longjmp;
124 /* Nonzero if function being compiled receives nonlocal gotos
125 from nested functions. */
127 int current_function_has_nonlocal_label;
129 /* Nonzero if function being compiled has nonlocal gotos to parent
132 int current_function_has_nonlocal_goto;
134 /* Nonzero if this function has a computed goto.
136 It is computed during find_basic_blocks or during stupid life
139 int current_function_has_computed_jump;
141 /* Nonzero if function being compiled contains nested functions. */
143 int current_function_contains_functions;
145 /* Nonzero if function being compiled doesn't modify the stack pointer
146 (ignoring the prologue and epilogue). This is only valid after
147 life_analysis has run. */
149 int current_function_sp_is_unchanging;
151 /* Nonzero if the function being compiled has the address of its
154 int current_function_addresses_labels;
156 /* Nonzero if the current function is a thunk (a lightweight function that
157 just adjusts one of its arguments and forwards to another function), so
158 we should try to cut corners where we can. */
159 int current_function_is_thunk;
161 /* Nonzero if function being compiled can call alloca,
162 either as a subroutine or builtin. */
164 int current_function_calls_alloca;
166 /* Nonzero if the current function returns a pointer type */
168 int current_function_returns_pointer;
170 /* If some insns can be deferred to the delay slots of the epilogue, the
171 delay list for them is recorded here. */
173 rtx current_function_epilogue_delay_list;
175 /* If function's args have a fixed size, this is that size, in bytes.
177 May affect compilation of return insn or of function epilogue. */
179 int current_function_args_size;
181 /* # bytes the prologue should push and pretend that the caller pushed them.
182 The prologue must do this, but only if parms can be passed in registers. */
184 int current_function_pretend_args_size;
186 /* # of bytes of outgoing arguments. If ACCUMULATE_OUTGOING_ARGS is
187 defined, the needed space is pushed by the prologue. */
189 int current_function_outgoing_args_size;
191 /* This is the offset from the arg pointer to the place where the first
192 anonymous arg can be found, if there is one. */
194 rtx current_function_arg_offset_rtx;
196 /* Nonzero if current function uses varargs.h or equivalent.
197 Zero for functions that use stdarg.h. */
199 int current_function_varargs;
201 /* Nonzero if current function uses stdarg.h or equivalent.
202 Zero for functions that use varargs.h. */
204 int current_function_stdarg;
206 /* Quantities of various kinds of registers
207 used for the current function's args. */
209 CUMULATIVE_ARGS current_function_args_info;
211 /* Name of function now being compiled. */
213 char *current_function_name;
215 /* If non-zero, an RTL expression for the location at which the current
216 function returns its result. If the current function returns its
217 result in a register, current_function_return_rtx will always be
218 the hard register containing the result. */
220 rtx current_function_return_rtx;
222 /* Nonzero if the current function uses the constant pool. */
224 int current_function_uses_const_pool;
226 /* Nonzero if the current function uses pic_offset_table_rtx. */
227 int current_function_uses_pic_offset_table;
229 /* The arg pointer hard register, or the pseudo into which it was copied. */
230 rtx current_function_internal_arg_pointer;
232 /* Language-specific reason why the current function cannot be made inline. */
233 char *current_function_cannot_inline;
235 /* Nonzero if instrumentation calls for function entry and exit should be
237 int current_function_instrument_entry_exit;
239 /* Nonzero if memory access checking be enabled in the current function. */
240 int current_function_check_memory_usage;
242 /* The FUNCTION_DECL for an inline function currently being expanded. */
243 tree inline_function_decl;
245 /* Number of function calls seen so far in current function. */
247 int function_call_count;
249 /* List (chain of TREE_LIST) of LABEL_DECLs for all nonlocal labels
250 (labels to which there can be nonlocal gotos from nested functions)
253 tree nonlocal_labels;
255 /* List (chain of EXPR_LIST) of stack slots that hold the current handlers
256 for nonlocal gotos. There is one for every nonlocal label in the function;
257 this list matches the one in nonlocal_labels.
258 Zero when function does not have nonlocal labels. */
260 rtx nonlocal_goto_handler_slots;
262 /* RTX for stack slot that holds the stack pointer value to restore
264 Zero when function does not have nonlocal labels. */
266 rtx nonlocal_goto_stack_level;
268 /* Label that will go on parm cleanup code, if any.
269 Jumping to this label runs cleanup code for parameters, if
270 such code must be run. Following this code is the logical return label. */
274 /* Label that will go on function epilogue.
275 Jumping to this label serves as a "return" instruction
276 on machines which require execution of the epilogue on all returns. */
280 /* List (chain of EXPR_LISTs) of pseudo-regs of SAVE_EXPRs.
281 So we can mark them all live at the end of the function, if nonopt. */
284 /* List (chain of EXPR_LISTs) of all stack slots in this function.
285 Made for the sake of unshare_all_rtl. */
288 /* Chain of all RTL_EXPRs that have insns in them. */
291 /* Label to jump back to for tail recursion, or 0 if we have
292 not yet needed one for this function. */
293 rtx tail_recursion_label;
295 /* Place after which to insert the tail_recursion_label if we need one. */
296 rtx tail_recursion_reentry;
298 /* Location at which to save the argument pointer if it will need to be
299 referenced. There are two cases where this is done: if nonlocal gotos
300 exist, or if vars stored at an offset from the argument pointer will be
301 needed by inner routines. */
303 rtx arg_pointer_save_area;
305 /* Offset to end of allocated area of stack frame.
306 If stack grows down, this is the address of the last stack slot allocated.
307 If stack grows up, this is the address for the next slot. */
308 HOST_WIDE_INT frame_offset;
310 /* List (chain of TREE_LISTs) of static chains for containing functions.
311 Each link has a FUNCTION_DECL in the TREE_PURPOSE and a reg rtx
312 in an RTL_EXPR in the TREE_VALUE. */
313 static tree context_display;
315 /* List (chain of TREE_LISTs) of trampolines for nested functions.
316 The trampoline sets up the static chain and jumps to the function.
317 We supply the trampoline's address when the function's address is requested.
319 Each link has a FUNCTION_DECL in the TREE_PURPOSE and a reg rtx
320 in an RTL_EXPR in the TREE_VALUE. */
321 static tree trampoline_list;
323 /* Insn after which register parms and SAVE_EXPRs are born, if nonopt. */
324 static rtx parm_birth_insn;
327 /* Nonzero if a stack slot has been generated whose address is not
328 actually valid. It means that the generated rtl must all be scanned
329 to detect and correct the invalid addresses where they occur. */
330 static int invalid_stack_slot;
333 /* Last insn of those whose job was to put parms into their nominal homes. */
334 static rtx last_parm_insn;
336 /* 1 + last pseudo register number possibly used for loading a copy
337 of a parameter of this function. */
340 /* Vector indexed by REGNO, containing location on stack in which
341 to put the parm which is nominally in pseudo register REGNO,
342 if we discover that that parm must go in the stack. The highest
343 element in this vector is one less than MAX_PARM_REG, above. */
344 rtx *parm_reg_stack_loc;
346 /* Nonzero once virtual register instantiation has been done.
347 assign_stack_local uses frame_pointer_rtx when this is nonzero. */
348 static int virtuals_instantiated;
350 /* These variables hold pointers to functions to
351 save and restore machine-specific data,
352 in push_function_context and pop_function_context. */
353 void (*save_machine_status) PROTO((struct function *));
354 void (*restore_machine_status) PROTO((struct function *));
356 /* Nonzero if we need to distinguish between the return value of this function
357 and the return value of a function called by this function. This helps
360 extern int rtx_equal_function_value_matters;
361 extern tree sequence_rtl_expr;
363 /* In order to evaluate some expressions, such as function calls returning
364 structures in memory, we need to temporarily allocate stack locations.
365 We record each allocated temporary in the following structure.
367 Associated with each temporary slot is a nesting level. When we pop up
368 one level, all temporaries associated with the previous level are freed.
369 Normally, all temporaries are freed after the execution of the statement
370 in which they were created. However, if we are inside a ({...}) grouping,
371 the result may be in a temporary and hence must be preserved. If the
372 result could be in a temporary, we preserve it if we can determine which
373 one it is in. If we cannot determine which temporary may contain the
374 result, all temporaries are preserved. A temporary is preserved by
375 pretending it was allocated at the previous nesting level.
377 Automatic variables are also assigned temporary slots, at the nesting
378 level where they are defined. They are marked a "kept" so that
379 free_temp_slots will not free them. */
383 /* Points to next temporary slot. */
384 struct temp_slot *next;
385 /* The rtx to used to reference the slot. */
387 /* The rtx used to represent the address if not the address of the
388 slot above. May be an EXPR_LIST if multiple addresses exist. */
390 /* The size, in units, of the slot. */
392 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
394 /* Non-zero if this temporary is currently in use. */
396 /* Non-zero if this temporary has its address taken. */
398 /* Nesting level at which this slot is being used. */
400 /* Non-zero if this should survive a call to free_temp_slots. */
402 /* The offset of the slot from the frame_pointer, including extra space
403 for alignment. This info is for combine_temp_slots. */
404 HOST_WIDE_INT base_offset;
405 /* The size of the slot, including extra space for alignment. This
406 info is for combine_temp_slots. */
407 HOST_WIDE_INT full_size;
410 /* List of all temporaries allocated, both available and in use. */
412 struct temp_slot *temp_slots;
414 /* Current nesting level for temporaries. */
418 /* Current nesting level for variables in a block. */
420 int var_temp_slot_level;
422 /* When temporaries are created by TARGET_EXPRs, they are created at
423 this level of temp_slot_level, so that they can remain allocated
424 until no longer needed. CLEANUP_POINT_EXPRs define the lifetime
426 int target_temp_slot_level;
428 /* This structure is used to record MEMs or pseudos used to replace VAR, any
429 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
430 maintain this list in case two operands of an insn were required to match;
431 in that case we must ensure we use the same replacement. */
433 struct fixup_replacement
437 struct fixup_replacement *next;
440 /* Forward declarations. */
442 static rtx assign_outer_stack_local PROTO ((enum machine_mode, HOST_WIDE_INT,
443 int, struct function *));
444 static struct temp_slot *find_temp_slot_from_address PROTO((rtx));
445 static void put_reg_into_stack PROTO((struct function *, rtx, tree,
446 enum machine_mode, enum machine_mode,
448 static void fixup_var_refs PROTO((rtx, enum machine_mode, int));
449 static struct fixup_replacement
450 *find_fixup_replacement PROTO((struct fixup_replacement **, rtx));
451 static void fixup_var_refs_insns PROTO((rtx, enum machine_mode, int,
453 static void fixup_var_refs_1 PROTO((rtx, enum machine_mode, rtx *, rtx,
454 struct fixup_replacement **));
455 static rtx fixup_memory_subreg PROTO((rtx, rtx, int));
456 static rtx walk_fixup_memory_subreg PROTO((rtx, rtx, int));
457 static rtx fixup_stack_1 PROTO((rtx, rtx));
458 static void optimize_bit_field PROTO((rtx, rtx, rtx *));
459 static void instantiate_decls PROTO((tree, int));
460 static void instantiate_decls_1 PROTO((tree, int));
461 static void instantiate_decl PROTO((rtx, int, int));
462 static int instantiate_virtual_regs_1 PROTO((rtx *, rtx, int));
463 static void delete_handlers PROTO((void));
464 static void pad_to_arg_alignment PROTO((struct args_size *, int));
465 #ifndef ARGS_GROW_DOWNWARD
466 static void pad_below PROTO((struct args_size *, enum machine_mode,
469 #ifdef ARGS_GROW_DOWNWARD
470 static tree round_down PROTO((tree, int));
472 static rtx round_trampoline_addr PROTO((rtx));
473 static tree blocks_nreverse PROTO((tree));
474 static int all_blocks PROTO((tree, tree *));
475 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
476 static int *record_insns PROTO((rtx));
477 static int contains PROTO((rtx, int *));
478 #endif /* HAVE_prologue || HAVE_epilogue */
479 static void put_addressof_into_stack PROTO((rtx));
480 static void purge_addressof_1 PROTO((rtx *, rtx, int, int));
482 /* Pointer to chain of `struct function' for containing functions. */
483 struct function *outer_function_chain;
485 /* Given a function decl for a containing function,
486 return the `struct function' for it. */
489 find_function_data (decl)
494 for (p = outer_function_chain; p; p = p->next)
501 /* Save the current context for compilation of a nested function.
502 This is called from language-specific code.
503 The caller is responsible for saving any language-specific status,
504 since this function knows only about language-independent variables. */
507 push_function_context_to (context)
510 struct function *p = (struct function *) xmalloc (sizeof (struct function));
512 p->next = outer_function_chain;
513 outer_function_chain = p;
515 p->name = current_function_name;
516 p->decl = current_function_decl;
517 p->pops_args = current_function_pops_args;
518 p->returns_struct = current_function_returns_struct;
519 p->returns_pcc_struct = current_function_returns_pcc_struct;
520 p->returns_pointer = current_function_returns_pointer;
521 p->needs_context = current_function_needs_context;
522 p->calls_setjmp = current_function_calls_setjmp;
523 p->calls_longjmp = current_function_calls_longjmp;
524 p->calls_alloca = current_function_calls_alloca;
525 p->has_nonlocal_label = current_function_has_nonlocal_label;
526 p->has_nonlocal_goto = current_function_has_nonlocal_goto;
527 p->contains_functions = current_function_contains_functions;
528 p->addresses_labels = current_function_addresses_labels;
529 p->is_thunk = current_function_is_thunk;
530 p->args_size = current_function_args_size;
531 p->pretend_args_size = current_function_pretend_args_size;
532 p->arg_offset_rtx = current_function_arg_offset_rtx;
533 p->varargs = current_function_varargs;
534 p->stdarg = current_function_stdarg;
535 p->uses_const_pool = current_function_uses_const_pool;
536 p->uses_pic_offset_table = current_function_uses_pic_offset_table;
537 p->internal_arg_pointer = current_function_internal_arg_pointer;
538 p->cannot_inline = current_function_cannot_inline;
539 p->max_parm_reg = max_parm_reg;
540 p->parm_reg_stack_loc = parm_reg_stack_loc;
541 p->outgoing_args_size = current_function_outgoing_args_size;
542 p->return_rtx = current_function_return_rtx;
543 p->nonlocal_goto_handler_slots = nonlocal_goto_handler_slots;
544 p->nonlocal_goto_stack_level = nonlocal_goto_stack_level;
545 p->nonlocal_labels = nonlocal_labels;
546 p->cleanup_label = cleanup_label;
547 p->return_label = return_label;
548 p->save_expr_regs = save_expr_regs;
549 p->stack_slot_list = stack_slot_list;
550 p->parm_birth_insn = parm_birth_insn;
551 p->frame_offset = frame_offset;
552 p->tail_recursion_label = tail_recursion_label;
553 p->tail_recursion_reentry = tail_recursion_reentry;
554 p->arg_pointer_save_area = arg_pointer_save_area;
555 p->rtl_expr_chain = rtl_expr_chain;
556 p->last_parm_insn = last_parm_insn;
557 p->context_display = context_display;
558 p->trampoline_list = trampoline_list;
559 p->function_call_count = function_call_count;
560 p->temp_slots = temp_slots;
561 p->temp_slot_level = temp_slot_level;
562 p->target_temp_slot_level = target_temp_slot_level;
563 p->var_temp_slot_level = var_temp_slot_level;
564 p->fixup_var_refs_queue = 0;
565 p->epilogue_delay_list = current_function_epilogue_delay_list;
566 p->args_info = current_function_args_info;
567 p->check_memory_usage = current_function_check_memory_usage;
568 p->instrument_entry_exit = current_function_instrument_entry_exit;
570 save_tree_status (p, context);
571 save_storage_status (p);
572 save_emit_status (p);
573 save_expr_status (p);
574 save_stmt_status (p);
575 save_varasm_status (p, context);
576 if (save_machine_status)
577 (*save_machine_status) (p);
581 push_function_context ()
583 push_function_context_to (current_function_decl);
586 /* Restore the last saved context, at the end of a nested function.
587 This function is called from language-specific code. */
590 pop_function_context_from (context)
593 struct function *p = outer_function_chain;
594 struct var_refs_queue *queue;
596 outer_function_chain = p->next;
598 current_function_contains_functions
599 = p->contains_functions || p->inline_obstacks
600 || context == current_function_decl;
601 current_function_addresses_labels = p->addresses_labels;
602 current_function_name = p->name;
603 current_function_decl = p->decl;
604 current_function_pops_args = p->pops_args;
605 current_function_returns_struct = p->returns_struct;
606 current_function_returns_pcc_struct = p->returns_pcc_struct;
607 current_function_returns_pointer = p->returns_pointer;
608 current_function_needs_context = p->needs_context;
609 current_function_calls_setjmp = p->calls_setjmp;
610 current_function_calls_longjmp = p->calls_longjmp;
611 current_function_calls_alloca = p->calls_alloca;
612 current_function_has_nonlocal_label = p->has_nonlocal_label;
613 current_function_has_nonlocal_goto = p->has_nonlocal_goto;
614 current_function_is_thunk = p->is_thunk;
615 current_function_args_size = p->args_size;
616 current_function_pretend_args_size = p->pretend_args_size;
617 current_function_arg_offset_rtx = p->arg_offset_rtx;
618 current_function_varargs = p->varargs;
619 current_function_stdarg = p->stdarg;
620 current_function_uses_const_pool = p->uses_const_pool;
621 current_function_uses_pic_offset_table = p->uses_pic_offset_table;
622 current_function_internal_arg_pointer = p->internal_arg_pointer;
623 current_function_cannot_inline = p->cannot_inline;
624 max_parm_reg = p->max_parm_reg;
625 parm_reg_stack_loc = p->parm_reg_stack_loc;
626 current_function_outgoing_args_size = p->outgoing_args_size;
627 current_function_return_rtx = p->return_rtx;
628 nonlocal_goto_handler_slots = p->nonlocal_goto_handler_slots;
629 nonlocal_goto_stack_level = p->nonlocal_goto_stack_level;
630 nonlocal_labels = p->nonlocal_labels;
631 cleanup_label = p->cleanup_label;
632 return_label = p->return_label;
633 save_expr_regs = p->save_expr_regs;
634 stack_slot_list = p->stack_slot_list;
635 parm_birth_insn = p->parm_birth_insn;
636 frame_offset = p->frame_offset;
637 tail_recursion_label = p->tail_recursion_label;
638 tail_recursion_reentry = p->tail_recursion_reentry;
639 arg_pointer_save_area = p->arg_pointer_save_area;
640 rtl_expr_chain = p->rtl_expr_chain;
641 last_parm_insn = p->last_parm_insn;
642 context_display = p->context_display;
643 trampoline_list = p->trampoline_list;
644 function_call_count = p->function_call_count;
645 temp_slots = p->temp_slots;
646 temp_slot_level = p->temp_slot_level;
647 target_temp_slot_level = p->target_temp_slot_level;
648 var_temp_slot_level = p->var_temp_slot_level;
649 current_function_epilogue_delay_list = p->epilogue_delay_list;
651 current_function_args_info = p->args_info;
652 current_function_check_memory_usage = p->check_memory_usage;
653 current_function_instrument_entry_exit = p->instrument_entry_exit;
655 restore_tree_status (p, context);
656 restore_storage_status (p);
657 restore_expr_status (p);
658 restore_emit_status (p);
659 restore_stmt_status (p);
660 restore_varasm_status (p);
662 if (restore_machine_status)
663 (*restore_machine_status) (p);
665 /* Finish doing put_var_into_stack for any of our variables
666 which became addressable during the nested function. */
667 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
668 fixup_var_refs (queue->modified, queue->promoted_mode, queue->unsignedp);
672 /* Reset variables that have known state during rtx generation. */
673 rtx_equal_function_value_matters = 1;
674 virtuals_instantiated = 0;
677 void pop_function_context ()
679 pop_function_context_from (current_function_decl);
682 /* Allocate fixed slots in the stack frame of the current function. */
684 /* Return size needed for stack frame based on slots so far allocated.
685 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
686 the caller may have to do that. */
691 #ifdef FRAME_GROWS_DOWNWARD
692 return -frame_offset;
698 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
699 with machine mode MODE.
701 ALIGN controls the amount of alignment for the address of the slot:
702 0 means according to MODE,
703 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
704 positive specifies alignment boundary in bits.
706 We do not round to stack_boundary here. */
709 assign_stack_local (mode, size, align)
710 enum machine_mode mode;
714 register rtx x, addr;
715 int bigend_correction = 0;
720 alignment = GET_MODE_ALIGNMENT (mode) / BITS_PER_UNIT;
722 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
724 else if (align == -1)
726 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
727 size = CEIL_ROUND (size, alignment);
730 alignment = align / BITS_PER_UNIT;
732 /* Round frame offset to that alignment.
733 We must be careful here, since FRAME_OFFSET might be negative and
734 division with a negative dividend isn't as well defined as we might
735 like. So we instead assume that ALIGNMENT is a power of two and
736 use logical operations which are unambiguous. */
737 #ifdef FRAME_GROWS_DOWNWARD
738 frame_offset = FLOOR_ROUND (frame_offset, alignment);
740 frame_offset = CEIL_ROUND (frame_offset, alignment);
743 /* On a big-endian machine, if we are allocating more space than we will use,
744 use the least significant bytes of those that are allocated. */
745 if (BYTES_BIG_ENDIAN && mode != BLKmode)
746 bigend_correction = size - GET_MODE_SIZE (mode);
748 #ifdef FRAME_GROWS_DOWNWARD
749 frame_offset -= size;
752 /* If we have already instantiated virtual registers, return the actual
753 address relative to the frame pointer. */
754 if (virtuals_instantiated)
755 addr = plus_constant (frame_pointer_rtx,
756 (frame_offset + bigend_correction
757 + STARTING_FRAME_OFFSET));
759 addr = plus_constant (virtual_stack_vars_rtx,
760 frame_offset + bigend_correction);
762 #ifndef FRAME_GROWS_DOWNWARD
763 frame_offset += size;
766 x = gen_rtx_MEM (mode, addr);
768 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, x, stack_slot_list);
773 /* Assign a stack slot in a containing function.
774 First three arguments are same as in preceding function.
775 The last argument specifies the function to allocate in. */
778 assign_outer_stack_local (mode, size, align, function)
779 enum machine_mode mode;
782 struct function *function;
784 register rtx x, addr;
785 int bigend_correction = 0;
788 /* Allocate in the memory associated with the function in whose frame
790 push_obstacks (function->function_obstack,
791 function->function_maybepermanent_obstack);
795 alignment = GET_MODE_ALIGNMENT (mode) / BITS_PER_UNIT;
797 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
799 else if (align == -1)
801 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
802 size = CEIL_ROUND (size, alignment);
805 alignment = align / BITS_PER_UNIT;
807 /* Round frame offset to that alignment. */
808 #ifdef FRAME_GROWS_DOWNWARD
809 function->frame_offset = FLOOR_ROUND (function->frame_offset, alignment);
811 function->frame_offset = CEIL_ROUND (function->frame_offset, alignment);
814 /* On a big-endian machine, if we are allocating more space than we will use,
815 use the least significant bytes of those that are allocated. */
816 if (BYTES_BIG_ENDIAN && mode != BLKmode)
817 bigend_correction = size - GET_MODE_SIZE (mode);
819 #ifdef FRAME_GROWS_DOWNWARD
820 function->frame_offset -= size;
822 addr = plus_constant (virtual_stack_vars_rtx,
823 function->frame_offset + bigend_correction);
824 #ifndef FRAME_GROWS_DOWNWARD
825 function->frame_offset += size;
828 x = gen_rtx_MEM (mode, addr);
830 function->stack_slot_list
831 = gen_rtx_EXPR_LIST (VOIDmode, x, function->stack_slot_list);
838 /* Allocate a temporary stack slot and record it for possible later
841 MODE is the machine mode to be given to the returned rtx.
843 SIZE is the size in units of the space required. We do no rounding here
844 since assign_stack_local will do any required rounding.
846 KEEP is 1 if this slot is to be retained after a call to
847 free_temp_slots. Automatic variables for a block are allocated
848 with this flag. KEEP is 2 if we allocate a longer term temporary,
849 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
850 if we are to allocate something at an inner level to be treated as
851 a variable in the block (e.g., a SAVE_EXPR). */
854 assign_stack_temp (mode, size, keep)
855 enum machine_mode mode;
859 struct temp_slot *p, *best_p = 0;
861 /* If SIZE is -1 it means that somebody tried to allocate a temporary
862 of a variable size. */
866 /* First try to find an available, already-allocated temporary that is the
867 exact size we require. */
868 for (p = temp_slots; p; p = p->next)
869 if (p->size == size && GET_MODE (p->slot) == mode && ! p->in_use)
872 /* If we didn't find, one, try one that is larger than what we want. We
873 find the smallest such. */
875 for (p = temp_slots; p; p = p->next)
876 if (p->size > size && GET_MODE (p->slot) == mode && ! p->in_use
877 && (best_p == 0 || best_p->size > p->size))
880 /* Make our best, if any, the one to use. */
883 /* If there are enough aligned bytes left over, make them into a new
884 temp_slot so that the extra bytes don't get wasted. Do this only
885 for BLKmode slots, so that we can be sure of the alignment. */
886 if (GET_MODE (best_p->slot) == BLKmode)
888 int alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
889 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
891 if (best_p->size - rounded_size >= alignment)
893 p = (struct temp_slot *) oballoc (sizeof (struct temp_slot));
894 p->in_use = p->addr_taken = 0;
895 p->size = best_p->size - rounded_size;
896 p->base_offset = best_p->base_offset + rounded_size;
897 p->full_size = best_p->full_size - rounded_size;
898 p->slot = gen_rtx_MEM (BLKmode,
899 plus_constant (XEXP (best_p->slot, 0),
903 p->next = temp_slots;
906 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
909 best_p->size = rounded_size;
910 best_p->full_size = rounded_size;
917 /* If we still didn't find one, make a new temporary. */
920 HOST_WIDE_INT frame_offset_old = frame_offset;
922 p = (struct temp_slot *) oballoc (sizeof (struct temp_slot));
924 /* If the temp slot mode doesn't indicate the alignment,
925 use the largest possible, so no one will be disappointed. */
926 p->slot = assign_stack_local (mode, size, mode == BLKmode ? -1 : 0);
928 /* The following slot size computation is necessary because we don't
929 know the actual size of the temporary slot until assign_stack_local
930 has performed all the frame alignment and size rounding for the
931 requested temporary. Note that extra space added for alignment
932 can be either above or below this stack slot depending on which
933 way the frame grows. We include the extra space if and only if it
934 is above this slot. */
935 #ifdef FRAME_GROWS_DOWNWARD
936 p->size = frame_offset_old - frame_offset;
941 /* Now define the fields used by combine_temp_slots. */
942 #ifdef FRAME_GROWS_DOWNWARD
943 p->base_offset = frame_offset;
944 p->full_size = frame_offset_old - frame_offset;
946 p->base_offset = frame_offset_old;
947 p->full_size = frame_offset - frame_offset_old;
950 p->next = temp_slots;
956 p->rtl_expr = sequence_rtl_expr;
960 p->level = target_temp_slot_level;
965 p->level = var_temp_slot_level;
970 p->level = temp_slot_level;
974 /* We may be reusing an old slot, so clear any MEM flags that may have been
976 RTX_UNCHANGING_P (p->slot) = 0;
977 MEM_IN_STRUCT_P (p->slot) = 0;
978 MEM_SCALAR_P (p->slot) = 0;
979 MEM_ALIAS_SET (p->slot) = 0;
983 /* Assign a temporary of given TYPE.
984 KEEP is as for assign_stack_temp.
985 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
986 it is 0 if a register is OK.
987 DONT_PROMOTE is 1 if we should not promote values in register
991 assign_temp (type, keep, memory_required, dont_promote)
997 enum machine_mode mode = TYPE_MODE (type);
998 int unsignedp = TREE_UNSIGNED (type);
1000 if (mode == BLKmode || memory_required)
1002 HOST_WIDE_INT size = int_size_in_bytes (type);
1005 /* Unfortunately, we don't yet know how to allocate variable-sized
1006 temporaries. However, sometimes we have a fixed upper limit on
1007 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
1008 instead. This is the case for Chill variable-sized strings. */
1009 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
1010 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
1011 && TREE_CODE (TYPE_ARRAY_MAX_SIZE (type)) == INTEGER_CST)
1012 size = TREE_INT_CST_LOW (TYPE_ARRAY_MAX_SIZE (type));
1014 tmp = assign_stack_temp (mode, size, keep);
1015 MEM_SET_IN_STRUCT_P (tmp, AGGREGATE_TYPE_P (type));
1019 #ifndef PROMOTE_FOR_CALL_ONLY
1021 mode = promote_mode (type, mode, &unsignedp, 0);
1024 return gen_reg_rtx (mode);
1027 /* Combine temporary stack slots which are adjacent on the stack.
1029 This allows for better use of already allocated stack space. This is only
1030 done for BLKmode slots because we can be sure that we won't have alignment
1031 problems in this case. */
1034 combine_temp_slots ()
1036 struct temp_slot *p, *q;
1037 struct temp_slot *prev_p, *prev_q;
1040 /* If there are a lot of temp slots, don't do anything unless
1041 high levels of optimizaton. */
1042 if (! flag_expensive_optimizations)
1043 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
1044 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
1047 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
1051 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
1052 for (q = p->next, prev_q = p; q; q = prev_q->next)
1055 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
1057 if (p->base_offset + p->full_size == q->base_offset)
1059 /* Q comes after P; combine Q into P. */
1061 p->full_size += q->full_size;
1064 else if (q->base_offset + q->full_size == p->base_offset)
1066 /* P comes after Q; combine P into Q. */
1068 q->full_size += p->full_size;
1073 /* Either delete Q or advance past it. */
1075 prev_q->next = q->next;
1079 /* Either delete P or advance past it. */
1083 prev_p->next = p->next;
1085 temp_slots = p->next;
1092 /* Find the temp slot corresponding to the object at address X. */
1094 static struct temp_slot *
1095 find_temp_slot_from_address (x)
1098 struct temp_slot *p;
1101 for (p = temp_slots; p; p = p->next)
1106 else if (XEXP (p->slot, 0) == x
1108 || (GET_CODE (x) == PLUS
1109 && XEXP (x, 0) == virtual_stack_vars_rtx
1110 && GET_CODE (XEXP (x, 1)) == CONST_INT
1111 && INTVAL (XEXP (x, 1)) >= p->base_offset
1112 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
1115 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
1116 for (next = p->address; next; next = XEXP (next, 1))
1117 if (XEXP (next, 0) == x)
1124 /* Indicate that NEW is an alternate way of referring to the temp slot
1125 that previously was known by OLD. */
1128 update_temp_slot_address (old, new)
1131 struct temp_slot *p = find_temp_slot_from_address (old);
1133 /* If none, return. Else add NEW as an alias. */
1136 else if (p->address == 0)
1140 if (GET_CODE (p->address) != EXPR_LIST)
1141 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1143 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1147 /* If X could be a reference to a temporary slot, mark the fact that its
1148 address was taken. */
1151 mark_temp_addr_taken (x)
1154 struct temp_slot *p;
1159 /* If X is not in memory or is at a constant address, it cannot be in
1160 a temporary slot. */
1161 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1164 p = find_temp_slot_from_address (XEXP (x, 0));
1169 /* If X could be a reference to a temporary slot, mark that slot as
1170 belonging to the to one level higher than the current level. If X
1171 matched one of our slots, just mark that one. Otherwise, we can't
1172 easily predict which it is, so upgrade all of them. Kept slots
1173 need not be touched.
1175 This is called when an ({...}) construct occurs and a statement
1176 returns a value in memory. */
1179 preserve_temp_slots (x)
1182 struct temp_slot *p = 0;
1184 /* If there is no result, we still might have some objects whose address
1185 were taken, so we need to make sure they stay around. */
1188 for (p = temp_slots; p; p = p->next)
1189 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1195 /* If X is a register that is being used as a pointer, see if we have
1196 a temporary slot we know it points to. To be consistent with
1197 the code below, we really should preserve all non-kept slots
1198 if we can't find a match, but that seems to be much too costly. */
1199 if (GET_CODE (x) == REG && REGNO_POINTER_FLAG (REGNO (x)))
1200 p = find_temp_slot_from_address (x);
1202 /* If X is not in memory or is at a constant address, it cannot be in
1203 a temporary slot, but it can contain something whose address was
1205 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1207 for (p = temp_slots; p; p = p->next)
1208 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1214 /* First see if we can find a match. */
1216 p = find_temp_slot_from_address (XEXP (x, 0));
1220 /* Move everything at our level whose address was taken to our new
1221 level in case we used its address. */
1222 struct temp_slot *q;
1224 if (p->level == temp_slot_level)
1226 for (q = temp_slots; q; q = q->next)
1227 if (q != p && q->addr_taken && q->level == p->level)
1236 /* Otherwise, preserve all non-kept slots at this level. */
1237 for (p = temp_slots; p; p = p->next)
1238 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1242 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1243 with that RTL_EXPR, promote it into a temporary slot at the present
1244 level so it will not be freed when we free slots made in the
1248 preserve_rtl_expr_result (x)
1251 struct temp_slot *p;
1253 /* If X is not in memory or is at a constant address, it cannot be in
1254 a temporary slot. */
1255 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1258 /* If we can find a match, move it to our level unless it is already at
1260 p = find_temp_slot_from_address (XEXP (x, 0));
1263 p->level = MIN (p->level, temp_slot_level);
1270 /* Free all temporaries used so far. This is normally called at the end
1271 of generating code for a statement. Don't free any temporaries
1272 currently in use for an RTL_EXPR that hasn't yet been emitted.
1273 We could eventually do better than this since it can be reused while
1274 generating the same RTL_EXPR, but this is complex and probably not
1280 struct temp_slot *p;
1282 for (p = temp_slots; p; p = p->next)
1283 if (p->in_use && p->level == temp_slot_level && ! p->keep
1284 && p->rtl_expr == 0)
1287 combine_temp_slots ();
1290 /* Free all temporary slots used in T, an RTL_EXPR node. */
1293 free_temps_for_rtl_expr (t)
1296 struct temp_slot *p;
1298 for (p = temp_slots; p; p = p->next)
1299 if (p->rtl_expr == t)
1302 combine_temp_slots ();
1305 /* Mark all temporaries ever allocated in this function as not suitable
1306 for reuse until the current level is exited. */
1309 mark_all_temps_used ()
1311 struct temp_slot *p;
1313 for (p = temp_slots; p; p = p->next)
1315 p->in_use = p->keep = 1;
1316 p->level = MIN (p->level, temp_slot_level);
1320 /* Push deeper into the nesting level for stack temporaries. */
1328 /* Likewise, but save the new level as the place to allocate variables
1332 push_temp_slots_for_block ()
1336 var_temp_slot_level = temp_slot_level;
1339 /* Likewise, but save the new level as the place to allocate temporaries
1340 for TARGET_EXPRs. */
1343 push_temp_slots_for_target ()
1347 target_temp_slot_level = temp_slot_level;
1350 /* Set and get the value of target_temp_slot_level. The only
1351 permitted use of these functions is to save and restore this value. */
1354 get_target_temp_slot_level ()
1356 return target_temp_slot_level;
1360 set_target_temp_slot_level (level)
1363 target_temp_slot_level = level;
1366 /* Pop a temporary nesting level. All slots in use in the current level
1372 struct temp_slot *p;
1374 for (p = temp_slots; p; p = p->next)
1375 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1378 combine_temp_slots ();
1383 /* Initialize temporary slots. */
1388 /* We have not allocated any temporaries yet. */
1390 temp_slot_level = 0;
1391 var_temp_slot_level = 0;
1392 target_temp_slot_level = 0;
1395 /* Retroactively move an auto variable from a register to a stack slot.
1396 This is done when an address-reference to the variable is seen. */
1399 put_var_into_stack (decl)
1403 enum machine_mode promoted_mode, decl_mode;
1404 struct function *function = 0;
1406 int can_use_addressof;
1408 context = decl_function_context (decl);
1410 /* Get the current rtl used for this object and its original mode. */
1411 reg = TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl) : DECL_RTL (decl);
1413 /* No need to do anything if decl has no rtx yet
1414 since in that case caller is setting TREE_ADDRESSABLE
1415 and a stack slot will be assigned when the rtl is made. */
1419 /* Get the declared mode for this object. */
1420 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1421 : DECL_MODE (decl));
1422 /* Get the mode it's actually stored in. */
1423 promoted_mode = GET_MODE (reg);
1425 /* If this variable comes from an outer function,
1426 find that function's saved context. */
1427 if (context != current_function_decl && context != inline_function_decl)
1428 for (function = outer_function_chain; function; function = function->next)
1429 if (function->decl == context)
1432 /* If this is a variable-size object with a pseudo to address it,
1433 put that pseudo into the stack, if the var is nonlocal. */
1434 if (DECL_NONLOCAL (decl)
1435 && GET_CODE (reg) == MEM
1436 && GET_CODE (XEXP (reg, 0)) == REG
1437 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1439 reg = XEXP (reg, 0);
1440 decl_mode = promoted_mode = GET_MODE (reg);
1446 /* FIXME make it work for promoted modes too */
1447 && decl_mode == promoted_mode
1448 #ifdef NON_SAVING_SETJMP
1449 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1453 /* If we can't use ADDRESSOF, make sure we see through one we already
1455 if (! can_use_addressof && GET_CODE (reg) == MEM
1456 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1457 reg = XEXP (XEXP (reg, 0), 0);
1459 /* Now we should have a value that resides in one or more pseudo regs. */
1461 if (GET_CODE (reg) == REG)
1463 /* If this variable lives in the current function and we don't need
1464 to put things in the stack for the sake of setjmp, try to keep it
1465 in a register until we know we actually need the address. */
1466 if (can_use_addressof)
1467 gen_mem_addressof (reg, decl);
1469 put_reg_into_stack (function, reg, TREE_TYPE (decl),
1470 promoted_mode, decl_mode,
1471 TREE_SIDE_EFFECTS (decl), 0,
1473 || DECL_INITIAL (decl) != 0);
1475 else if (GET_CODE (reg) == CONCAT)
1477 /* A CONCAT contains two pseudos; put them both in the stack.
1478 We do it so they end up consecutive. */
1479 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1480 tree part_type = TREE_TYPE (TREE_TYPE (decl));
1481 #ifdef FRAME_GROWS_DOWNWARD
1482 /* Since part 0 should have a lower address, do it second. */
1483 put_reg_into_stack (function, XEXP (reg, 1), part_type, part_mode,
1484 part_mode, TREE_SIDE_EFFECTS (decl), 0,
1485 TREE_USED (decl) || DECL_INITIAL (decl) != 0);
1486 put_reg_into_stack (function, XEXP (reg, 0), part_type, part_mode,
1487 part_mode, TREE_SIDE_EFFECTS (decl), 0,
1488 TREE_USED (decl) || DECL_INITIAL (decl) != 0);
1490 put_reg_into_stack (function, XEXP (reg, 0), part_type, part_mode,
1491 part_mode, TREE_SIDE_EFFECTS (decl), 0,
1492 TREE_USED (decl) || DECL_INITIAL (decl) != 0);
1493 put_reg_into_stack (function, XEXP (reg, 1), part_type, part_mode,
1494 part_mode, TREE_SIDE_EFFECTS (decl), 0,
1495 TREE_USED (decl) || DECL_INITIAL (decl) != 0);
1498 /* Change the CONCAT into a combined MEM for both parts. */
1499 PUT_CODE (reg, MEM);
1500 MEM_VOLATILE_P (reg) = MEM_VOLATILE_P (XEXP (reg, 0));
1501 MEM_ALIAS_SET (reg) = get_alias_set (decl);
1503 /* The two parts are in memory order already.
1504 Use the lower parts address as ours. */
1505 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1506 /* Prevent sharing of rtl that might lose. */
1507 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1508 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1513 if (current_function_check_memory_usage)
1514 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
1515 XEXP (reg, 0), ptr_mode,
1516 GEN_INT (GET_MODE_SIZE (GET_MODE (reg))),
1517 TYPE_MODE (sizetype),
1518 GEN_INT (MEMORY_USE_RW),
1519 TYPE_MODE (integer_type_node));
1522 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1523 into the stack frame of FUNCTION (0 means the current function).
1524 DECL_MODE is the machine mode of the user-level data type.
1525 PROMOTED_MODE is the machine mode of the register.
1526 VOLATILE_P is nonzero if this is for a "volatile" decl.
1527 USED_P is nonzero if this reg might have already been used in an insn. */
1530 put_reg_into_stack (function, reg, type, promoted_mode, decl_mode, volatile_p,
1531 original_regno, used_p)
1532 struct function *function;
1535 enum machine_mode promoted_mode, decl_mode;
1541 int regno = original_regno;
1544 regno = REGNO (reg);
1548 if (regno < function->max_parm_reg)
1549 new = function->parm_reg_stack_loc[regno];
1551 new = assign_outer_stack_local (decl_mode, GET_MODE_SIZE (decl_mode),
1556 if (regno < max_parm_reg)
1557 new = parm_reg_stack_loc[regno];
1559 new = assign_stack_local (decl_mode, GET_MODE_SIZE (decl_mode), 0);
1562 PUT_MODE (reg, decl_mode);
1563 XEXP (reg, 0) = XEXP (new, 0);
1564 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1565 MEM_VOLATILE_P (reg) = volatile_p;
1566 PUT_CODE (reg, MEM);
1568 /* If this is a memory ref that contains aggregate components,
1569 mark it as such for cse and loop optimize. If we are reusing a
1570 previously generated stack slot, then we need to copy the bit in
1571 case it was set for other reasons. For instance, it is set for
1572 __builtin_va_alist. */
1573 MEM_SET_IN_STRUCT_P (reg,
1574 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1575 MEM_ALIAS_SET (reg) = get_alias_set (type);
1577 /* Now make sure that all refs to the variable, previously made
1578 when it was a register, are fixed up to be valid again. */
1580 if (used_p && function != 0)
1582 struct var_refs_queue *temp;
1584 /* Variable is inherited; fix it up when we get back to its function. */
1585 push_obstacks (function->function_obstack,
1586 function->function_maybepermanent_obstack);
1588 /* See comment in restore_tree_status in tree.c for why this needs to be
1589 on saveable obstack. */
1591 = (struct var_refs_queue *) savealloc (sizeof (struct var_refs_queue));
1592 temp->modified = reg;
1593 temp->promoted_mode = promoted_mode;
1594 temp->unsignedp = TREE_UNSIGNED (type);
1595 temp->next = function->fixup_var_refs_queue;
1596 function->fixup_var_refs_queue = temp;
1600 /* Variable is local; fix it up now. */
1601 fixup_var_refs (reg, promoted_mode, TREE_UNSIGNED (type));
1605 fixup_var_refs (var, promoted_mode, unsignedp)
1607 enum machine_mode promoted_mode;
1611 rtx first_insn = get_insns ();
1612 struct sequence_stack *stack = sequence_stack;
1613 tree rtl_exps = rtl_expr_chain;
1615 /* Must scan all insns for stack-refs that exceed the limit. */
1616 fixup_var_refs_insns (var, promoted_mode, unsignedp, first_insn, stack == 0);
1618 /* Scan all pending sequences too. */
1619 for (; stack; stack = stack->next)
1621 push_to_sequence (stack->first);
1622 fixup_var_refs_insns (var, promoted_mode, unsignedp,
1623 stack->first, stack->next != 0);
1624 /* Update remembered end of sequence
1625 in case we added an insn at the end. */
1626 stack->last = get_last_insn ();
1630 /* Scan all waiting RTL_EXPRs too. */
1631 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1633 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1634 if (seq != const0_rtx && seq != 0)
1636 push_to_sequence (seq);
1637 fixup_var_refs_insns (var, promoted_mode, unsignedp, seq, 0);
1642 /* Scan the catch clauses for exception handling too. */
1643 push_to_sequence (catch_clauses);
1644 fixup_var_refs_insns (var, promoted_mode, unsignedp, catch_clauses, 0);
1648 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1649 some part of an insn. Return a struct fixup_replacement whose OLD
1650 value is equal to X. Allocate a new structure if no such entry exists. */
1652 static struct fixup_replacement *
1653 find_fixup_replacement (replacements, x)
1654 struct fixup_replacement **replacements;
1657 struct fixup_replacement *p;
1659 /* See if we have already replaced this. */
1660 for (p = *replacements; p && p->old != x; p = p->next)
1665 p = (struct fixup_replacement *) oballoc (sizeof (struct fixup_replacement));
1668 p->next = *replacements;
1675 /* Scan the insn-chain starting with INSN for refs to VAR
1676 and fix them up. TOPLEVEL is nonzero if this chain is the
1677 main chain of insns for the current function. */
1680 fixup_var_refs_insns (var, promoted_mode, unsignedp, insn, toplevel)
1682 enum machine_mode promoted_mode;
1691 rtx next = NEXT_INSN (insn);
1692 rtx set, prev, prev_set;
1695 if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
1697 /* If this is a CLOBBER of VAR, delete it.
1699 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1700 and REG_RETVAL notes too. */
1701 if (GET_CODE (PATTERN (insn)) == CLOBBER
1702 && (XEXP (PATTERN (insn), 0) == var
1703 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1704 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1705 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1707 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1708 /* The REG_LIBCALL note will go away since we are going to
1709 turn INSN into a NOTE, so just delete the
1710 corresponding REG_RETVAL note. */
1711 remove_note (XEXP (note, 0),
1712 find_reg_note (XEXP (note, 0), REG_RETVAL,
1715 /* In unoptimized compilation, we shouldn't call delete_insn
1716 except in jump.c doing warnings. */
1717 PUT_CODE (insn, NOTE);
1718 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1719 NOTE_SOURCE_FILE (insn) = 0;
1722 /* The insn to load VAR from a home in the arglist
1723 is now a no-op. When we see it, just delete it.
1724 Similarly if this is storing VAR from a register from which
1725 it was loaded in the previous insn. This will occur
1726 when an ADDRESSOF was made for an arglist slot. */
1728 && (set = single_set (insn)) != 0
1729 && SET_DEST (set) == var
1730 /* If this represents the result of an insn group,
1731 don't delete the insn. */
1732 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1733 && (rtx_equal_p (SET_SRC (set), var)
1734 || (GET_CODE (SET_SRC (set)) == REG
1735 && (prev = prev_nonnote_insn (insn)) != 0
1736 && (prev_set = single_set (prev)) != 0
1737 && SET_DEST (prev_set) == SET_SRC (set)
1738 && rtx_equal_p (SET_SRC (prev_set), var))))
1740 /* In unoptimized compilation, we shouldn't call delete_insn
1741 except in jump.c doing warnings. */
1742 PUT_CODE (insn, NOTE);
1743 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1744 NOTE_SOURCE_FILE (insn) = 0;
1745 if (insn == last_parm_insn)
1746 last_parm_insn = PREV_INSN (next);
1750 struct fixup_replacement *replacements = 0;
1751 rtx next_insn = NEXT_INSN (insn);
1753 if (SMALL_REGISTER_CLASSES)
1755 /* If the insn that copies the results of a CALL_INSN
1756 into a pseudo now references VAR, we have to use an
1757 intermediate pseudo since we want the life of the
1758 return value register to be only a single insn.
1760 If we don't use an intermediate pseudo, such things as
1761 address computations to make the address of VAR valid
1762 if it is not can be placed between the CALL_INSN and INSN.
1764 To make sure this doesn't happen, we record the destination
1765 of the CALL_INSN and see if the next insn uses both that
1768 if (call_dest != 0 && GET_CODE (insn) == INSN
1769 && reg_mentioned_p (var, PATTERN (insn))
1770 && reg_mentioned_p (call_dest, PATTERN (insn)))
1772 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1774 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1776 PATTERN (insn) = replace_rtx (PATTERN (insn),
1780 if (GET_CODE (insn) == CALL_INSN
1781 && GET_CODE (PATTERN (insn)) == SET)
1782 call_dest = SET_DEST (PATTERN (insn));
1783 else if (GET_CODE (insn) == CALL_INSN
1784 && GET_CODE (PATTERN (insn)) == PARALLEL
1785 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1786 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1791 /* See if we have to do anything to INSN now that VAR is in
1792 memory. If it needs to be loaded into a pseudo, use a single
1793 pseudo for the entire insn in case there is a MATCH_DUP
1794 between two operands. We pass a pointer to the head of
1795 a list of struct fixup_replacements. If fixup_var_refs_1
1796 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1797 it will record them in this list.
1799 If it allocated a pseudo for any replacement, we copy into
1802 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1805 /* If this is last_parm_insn, and any instructions were output
1806 after it to fix it up, then we must set last_parm_insn to
1807 the last such instruction emitted. */
1808 if (insn == last_parm_insn)
1809 last_parm_insn = PREV_INSN (next_insn);
1811 while (replacements)
1813 if (GET_CODE (replacements->new) == REG)
1818 /* OLD might be a (subreg (mem)). */
1819 if (GET_CODE (replacements->old) == SUBREG)
1821 = fixup_memory_subreg (replacements->old, insn, 0);
1824 = fixup_stack_1 (replacements->old, insn);
1826 insert_before = insn;
1828 /* If we are changing the mode, do a conversion.
1829 This might be wasteful, but combine.c will
1830 eliminate much of the waste. */
1832 if (GET_MODE (replacements->new)
1833 != GET_MODE (replacements->old))
1836 convert_move (replacements->new,
1837 replacements->old, unsignedp);
1838 seq = gen_sequence ();
1842 seq = gen_move_insn (replacements->new,
1845 emit_insn_before (seq, insert_before);
1848 replacements = replacements->next;
1852 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1853 But don't touch other insns referred to by reg-notes;
1854 we will get them elsewhere. */
1855 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
1856 if (GET_CODE (note) != INSN_LIST)
1858 = walk_fixup_memory_subreg (XEXP (note, 0), insn, 1);
1864 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1865 See if the rtx expression at *LOC in INSN needs to be changed.
1867 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1868 contain a list of original rtx's and replacements. If we find that we need
1869 to modify this insn by replacing a memory reference with a pseudo or by
1870 making a new MEM to implement a SUBREG, we consult that list to see if
1871 we have already chosen a replacement. If none has already been allocated,
1872 we allocate it and update the list. fixup_var_refs_insns will copy VAR
1873 or the SUBREG, as appropriate, to the pseudo. */
1876 fixup_var_refs_1 (var, promoted_mode, loc, insn, replacements)
1878 enum machine_mode promoted_mode;
1881 struct fixup_replacement **replacements;
1884 register rtx x = *loc;
1885 RTX_CODE code = GET_CODE (x);
1887 register rtx tem, tem1;
1888 struct fixup_replacement *replacement;
1893 if (XEXP (x, 0) == var)
1895 /* Prevent sharing of rtl that might lose. */
1896 rtx sub = copy_rtx (XEXP (var, 0));
1900 if (! validate_change (insn, loc, sub, 0))
1902 rtx y = force_operand (sub, NULL_RTX);
1904 if (! validate_change (insn, loc, y, 0))
1905 *loc = copy_to_reg (y);
1908 emit_insn_before (gen_sequence (), insn);
1916 /* If we already have a replacement, use it. Otherwise,
1917 try to fix up this address in case it is invalid. */
1919 replacement = find_fixup_replacement (replacements, var);
1920 if (replacement->new)
1922 *loc = replacement->new;
1926 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1928 /* Unless we are forcing memory to register or we changed the mode,
1929 we can leave things the way they are if the insn is valid. */
1931 INSN_CODE (insn) = -1;
1932 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1933 && recog_memoized (insn) >= 0)
1936 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1940 /* If X contains VAR, we need to unshare it here so that we update
1941 each occurrence separately. But all identical MEMs in one insn
1942 must be replaced with the same rtx because of the possibility of
1945 if (reg_mentioned_p (var, x))
1947 replacement = find_fixup_replacement (replacements, x);
1948 if (replacement->new == 0)
1949 replacement->new = copy_most_rtx (x, var);
1951 *loc = x = replacement->new;
1967 /* Note that in some cases those types of expressions are altered
1968 by optimize_bit_field, and do not survive to get here. */
1969 if (XEXP (x, 0) == var
1970 || (GET_CODE (XEXP (x, 0)) == SUBREG
1971 && SUBREG_REG (XEXP (x, 0)) == var))
1973 /* Get TEM as a valid MEM in the mode presently in the insn.
1975 We don't worry about the possibility of MATCH_DUP here; it
1976 is highly unlikely and would be tricky to handle. */
1979 if (GET_CODE (tem) == SUBREG)
1981 if (GET_MODE_BITSIZE (GET_MODE (tem))
1982 > GET_MODE_BITSIZE (GET_MODE (var)))
1984 replacement = find_fixup_replacement (replacements, var);
1985 if (replacement->new == 0)
1986 replacement->new = gen_reg_rtx (GET_MODE (var));
1987 SUBREG_REG (tem) = replacement->new;
1990 tem = fixup_memory_subreg (tem, insn, 0);
1993 tem = fixup_stack_1 (tem, insn);
1995 /* Unless we want to load from memory, get TEM into the proper mode
1996 for an extract from memory. This can only be done if the
1997 extract is at a constant position and length. */
1999 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
2000 && GET_CODE (XEXP (x, 2)) == CONST_INT
2001 && ! mode_dependent_address_p (XEXP (tem, 0))
2002 && ! MEM_VOLATILE_P (tem))
2004 enum machine_mode wanted_mode = VOIDmode;
2005 enum machine_mode is_mode = GET_MODE (tem);
2006 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
2009 if (GET_CODE (x) == ZERO_EXTRACT)
2011 wanted_mode = insn_operand_mode[(int) CODE_FOR_extzv][1];
2012 if (wanted_mode == VOIDmode)
2013 wanted_mode = word_mode;
2017 if (GET_CODE (x) == SIGN_EXTRACT)
2019 wanted_mode = insn_operand_mode[(int) CODE_FOR_extv][1];
2020 if (wanted_mode == VOIDmode)
2021 wanted_mode = word_mode;
2024 /* If we have a narrower mode, we can do something. */
2025 if (wanted_mode != VOIDmode
2026 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2028 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2029 rtx old_pos = XEXP (x, 2);
2032 /* If the bytes and bits are counted differently, we
2033 must adjust the offset. */
2034 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2035 offset = (GET_MODE_SIZE (is_mode)
2036 - GET_MODE_SIZE (wanted_mode) - offset);
2038 pos %= GET_MODE_BITSIZE (wanted_mode);
2040 newmem = gen_rtx_MEM (wanted_mode,
2041 plus_constant (XEXP (tem, 0), offset));
2042 RTX_UNCHANGING_P (newmem) = RTX_UNCHANGING_P (tem);
2043 MEM_COPY_ATTRIBUTES (newmem, tem);
2045 /* Make the change and see if the insn remains valid. */
2046 INSN_CODE (insn) = -1;
2047 XEXP (x, 0) = newmem;
2048 XEXP (x, 2) = GEN_INT (pos);
2050 if (recog_memoized (insn) >= 0)
2053 /* Otherwise, restore old position. XEXP (x, 0) will be
2055 XEXP (x, 2) = old_pos;
2059 /* If we get here, the bitfield extract insn can't accept a memory
2060 reference. Copy the input into a register. */
2062 tem1 = gen_reg_rtx (GET_MODE (tem));
2063 emit_insn_before (gen_move_insn (tem1, tem), insn);
2070 if (SUBREG_REG (x) == var)
2072 /* If this is a special SUBREG made because VAR was promoted
2073 from a wider mode, replace it with VAR and call ourself
2074 recursively, this time saying that the object previously
2075 had its current mode (by virtue of the SUBREG). */
2077 if (SUBREG_PROMOTED_VAR_P (x))
2080 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements);
2084 /* If this SUBREG makes VAR wider, it has become a paradoxical
2085 SUBREG with VAR in memory, but these aren't allowed at this
2086 stage of the compilation. So load VAR into a pseudo and take
2087 a SUBREG of that pseudo. */
2088 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2090 replacement = find_fixup_replacement (replacements, var);
2091 if (replacement->new == 0)
2092 replacement->new = gen_reg_rtx (GET_MODE (var));
2093 SUBREG_REG (x) = replacement->new;
2097 /* See if we have already found a replacement for this SUBREG.
2098 If so, use it. Otherwise, make a MEM and see if the insn
2099 is recognized. If not, or if we should force MEM into a register,
2100 make a pseudo for this SUBREG. */
2101 replacement = find_fixup_replacement (replacements, x);
2102 if (replacement->new)
2104 *loc = replacement->new;
2108 replacement->new = *loc = fixup_memory_subreg (x, insn, 0);
2110 INSN_CODE (insn) = -1;
2111 if (! flag_force_mem && recog_memoized (insn) >= 0)
2114 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2120 /* First do special simplification of bit-field references. */
2121 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2122 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2123 optimize_bit_field (x, insn, 0);
2124 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2125 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2126 optimize_bit_field (x, insn, NULL_PTR);
2128 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2129 into a register and then store it back out. */
2130 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2131 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2132 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2133 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2134 > GET_MODE_SIZE (GET_MODE (var))))
2136 replacement = find_fixup_replacement (replacements, var);
2137 if (replacement->new == 0)
2138 replacement->new = gen_reg_rtx (GET_MODE (var));
2140 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2141 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2144 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2145 insn into a pseudo and store the low part of the pseudo into VAR. */
2146 if (GET_CODE (SET_DEST (x)) == SUBREG
2147 && SUBREG_REG (SET_DEST (x)) == var
2148 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2149 > GET_MODE_SIZE (GET_MODE (var))))
2151 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2152 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2159 rtx dest = SET_DEST (x);
2160 rtx src = SET_SRC (x);
2162 rtx outerdest = dest;
2165 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2166 || GET_CODE (dest) == SIGN_EXTRACT
2167 || GET_CODE (dest) == ZERO_EXTRACT)
2168 dest = XEXP (dest, 0);
2170 if (GET_CODE (src) == SUBREG)
2171 src = XEXP (src, 0);
2173 /* If VAR does not appear at the top level of the SET
2174 just scan the lower levels of the tree. */
2176 if (src != var && dest != var)
2179 /* We will need to rerecognize this insn. */
2180 INSN_CODE (insn) = -1;
2183 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var)
2185 /* Since this case will return, ensure we fixup all the
2187 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2188 insn, replacements);
2189 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2190 insn, replacements);
2191 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2192 insn, replacements);
2194 tem = XEXP (outerdest, 0);
2196 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2197 that may appear inside a ZERO_EXTRACT.
2198 This was legitimate when the MEM was a REG. */
2199 if (GET_CODE (tem) == SUBREG
2200 && SUBREG_REG (tem) == var)
2201 tem = fixup_memory_subreg (tem, insn, 0);
2203 tem = fixup_stack_1 (tem, insn);
2205 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2206 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2207 && ! mode_dependent_address_p (XEXP (tem, 0))
2208 && ! MEM_VOLATILE_P (tem))
2210 enum machine_mode wanted_mode;
2211 enum machine_mode is_mode = GET_MODE (tem);
2212 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2214 wanted_mode = insn_operand_mode[(int) CODE_FOR_insv][0];
2215 if (wanted_mode == VOIDmode)
2216 wanted_mode = word_mode;
2218 /* If we have a narrower mode, we can do something. */
2219 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2221 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2222 rtx old_pos = XEXP (outerdest, 2);
2225 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2226 offset = (GET_MODE_SIZE (is_mode)
2227 - GET_MODE_SIZE (wanted_mode) - offset);
2229 pos %= GET_MODE_BITSIZE (wanted_mode);
2231 newmem = gen_rtx_MEM (wanted_mode,
2232 plus_constant (XEXP (tem, 0), offset));
2233 RTX_UNCHANGING_P (newmem) = RTX_UNCHANGING_P (tem);
2234 MEM_COPY_ATTRIBUTES (newmem, tem);
2236 /* Make the change and see if the insn remains valid. */
2237 INSN_CODE (insn) = -1;
2238 XEXP (outerdest, 0) = newmem;
2239 XEXP (outerdest, 2) = GEN_INT (pos);
2241 if (recog_memoized (insn) >= 0)
2244 /* Otherwise, restore old position. XEXP (x, 0) will be
2246 XEXP (outerdest, 2) = old_pos;
2250 /* If we get here, the bit-field store doesn't allow memory
2251 or isn't located at a constant position. Load the value into
2252 a register, do the store, and put it back into memory. */
2254 tem1 = gen_reg_rtx (GET_MODE (tem));
2255 emit_insn_before (gen_move_insn (tem1, tem), insn);
2256 emit_insn_after (gen_move_insn (tem, tem1), insn);
2257 XEXP (outerdest, 0) = tem1;
2262 /* STRICT_LOW_PART is a no-op on memory references
2263 and it can cause combinations to be unrecognizable,
2266 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2267 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2269 /* A valid insn to copy VAR into or out of a register
2270 must be left alone, to avoid an infinite loop here.
2271 If the reference to VAR is by a subreg, fix that up,
2272 since SUBREG is not valid for a memref.
2273 Also fix up the address of the stack slot.
2275 Note that we must not try to recognize the insn until
2276 after we know that we have valid addresses and no
2277 (subreg (mem ...) ...) constructs, since these interfere
2278 with determining the validity of the insn. */
2280 if ((SET_SRC (x) == var
2281 || (GET_CODE (SET_SRC (x)) == SUBREG
2282 && SUBREG_REG (SET_SRC (x)) == var))
2283 && (GET_CODE (SET_DEST (x)) == REG
2284 || (GET_CODE (SET_DEST (x)) == SUBREG
2285 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2286 && GET_MODE (var) == promoted_mode
2287 && x == single_set (insn))
2291 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2292 if (replacement->new)
2293 SET_SRC (x) = replacement->new;
2294 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2295 SET_SRC (x) = replacement->new
2296 = fixup_memory_subreg (SET_SRC (x), insn, 0);
2298 SET_SRC (x) = replacement->new
2299 = fixup_stack_1 (SET_SRC (x), insn);
2301 if (recog_memoized (insn) >= 0)
2304 /* INSN is not valid, but we know that we want to
2305 copy SET_SRC (x) to SET_DEST (x) in some way. So
2306 we generate the move and see whether it requires more
2307 than one insn. If it does, we emit those insns and
2308 delete INSN. Otherwise, we an just replace the pattern
2309 of INSN; we have already verified above that INSN has
2310 no other function that to do X. */
2312 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2313 if (GET_CODE (pat) == SEQUENCE)
2315 emit_insn_after (pat, insn);
2316 PUT_CODE (insn, NOTE);
2317 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
2318 NOTE_SOURCE_FILE (insn) = 0;
2321 PATTERN (insn) = pat;
2326 if ((SET_DEST (x) == var
2327 || (GET_CODE (SET_DEST (x)) == SUBREG
2328 && SUBREG_REG (SET_DEST (x)) == var))
2329 && (GET_CODE (SET_SRC (x)) == REG
2330 || (GET_CODE (SET_SRC (x)) == SUBREG
2331 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2332 && GET_MODE (var) == promoted_mode
2333 && x == single_set (insn))
2337 if (GET_CODE (SET_DEST (x)) == SUBREG)
2338 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn, 0);
2340 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2342 if (recog_memoized (insn) >= 0)
2345 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2346 if (GET_CODE (pat) == SEQUENCE)
2348 emit_insn_after (pat, insn);
2349 PUT_CODE (insn, NOTE);
2350 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
2351 NOTE_SOURCE_FILE (insn) = 0;
2354 PATTERN (insn) = pat;
2359 /* Otherwise, storing into VAR must be handled specially
2360 by storing into a temporary and copying that into VAR
2361 with a new insn after this one. Note that this case
2362 will be used when storing into a promoted scalar since
2363 the insn will now have different modes on the input
2364 and output and hence will be invalid (except for the case
2365 of setting it to a constant, which does not need any
2366 change if it is valid). We generate extra code in that case,
2367 but combine.c will eliminate it. */
2372 rtx fixeddest = SET_DEST (x);
2374 /* STRICT_LOW_PART can be discarded, around a MEM. */
2375 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2376 fixeddest = XEXP (fixeddest, 0);
2377 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2378 if (GET_CODE (fixeddest) == SUBREG)
2380 fixeddest = fixup_memory_subreg (fixeddest, insn, 0);
2381 promoted_mode = GET_MODE (fixeddest);
2384 fixeddest = fixup_stack_1 (fixeddest, insn);
2386 temp = gen_reg_rtx (promoted_mode);
2388 emit_insn_after (gen_move_insn (fixeddest,
2389 gen_lowpart (GET_MODE (fixeddest),
2393 SET_DEST (x) = temp;
2401 /* Nothing special about this RTX; fix its operands. */
2403 fmt = GET_RTX_FORMAT (code);
2404 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2407 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements);
2411 for (j = 0; j < XVECLEN (x, i); j++)
2412 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2413 insn, replacements);
2418 /* Given X, an rtx of the form (SUBREG:m1 (MEM:m2 addr)),
2419 return an rtx (MEM:m1 newaddr) which is equivalent.
2420 If any insns must be emitted to compute NEWADDR, put them before INSN.
2422 UNCRITICAL nonzero means accept paradoxical subregs.
2423 This is used for subregs found inside REG_NOTES. */
2426 fixup_memory_subreg (x, insn, uncritical)
2431 int offset = SUBREG_WORD (x) * UNITS_PER_WORD;
2432 rtx addr = XEXP (SUBREG_REG (x), 0);
2433 enum machine_mode mode = GET_MODE (x);
2436 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2437 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))
2441 if (BYTES_BIG_ENDIAN)
2442 offset += (MIN (UNITS_PER_WORD, GET_MODE_SIZE (GET_MODE (SUBREG_REG (x))))
2443 - MIN (UNITS_PER_WORD, GET_MODE_SIZE (mode)));
2444 addr = plus_constant (addr, offset);
2445 if (!flag_force_addr && memory_address_p (mode, addr))
2446 /* Shortcut if no insns need be emitted. */
2447 return change_address (SUBREG_REG (x), mode, addr);
2449 result = change_address (SUBREG_REG (x), mode, addr);
2450 emit_insn_before (gen_sequence (), insn);
2455 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2456 Replace subexpressions of X in place.
2457 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2458 Otherwise return X, with its contents possibly altered.
2460 If any insns must be emitted to compute NEWADDR, put them before INSN.
2462 UNCRITICAL is as in fixup_memory_subreg. */
2465 walk_fixup_memory_subreg (x, insn, uncritical)
2470 register enum rtx_code code;
2477 code = GET_CODE (x);
2479 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2480 return fixup_memory_subreg (x, insn, uncritical);
2482 /* Nothing special about this RTX; fix its operands. */
2484 fmt = GET_RTX_FORMAT (code);
2485 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2488 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn, uncritical);
2492 for (j = 0; j < XVECLEN (x, i); j++)
2494 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn, uncritical);
2500 /* For each memory ref within X, if it refers to a stack slot
2501 with an out of range displacement, put the address in a temp register
2502 (emitting new insns before INSN to load these registers)
2503 and alter the memory ref to use that register.
2504 Replace each such MEM rtx with a copy, to avoid clobberage. */
2507 fixup_stack_1 (x, insn)
2512 register RTX_CODE code = GET_CODE (x);
2517 register rtx ad = XEXP (x, 0);
2518 /* If we have address of a stack slot but it's not valid
2519 (displacement is too large), compute the sum in a register. */
2520 if (GET_CODE (ad) == PLUS
2521 && GET_CODE (XEXP (ad, 0)) == REG
2522 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2523 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2524 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2525 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2526 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2528 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2529 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2530 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2531 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2534 if (memory_address_p (GET_MODE (x), ad))
2538 temp = copy_to_reg (ad);
2539 seq = gen_sequence ();
2541 emit_insn_before (seq, insn);
2542 return change_address (x, VOIDmode, temp);
2547 fmt = GET_RTX_FORMAT (code);
2548 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2551 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2555 for (j = 0; j < XVECLEN (x, i); j++)
2556 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2562 /* Optimization: a bit-field instruction whose field
2563 happens to be a byte or halfword in memory
2564 can be changed to a move instruction.
2566 We call here when INSN is an insn to examine or store into a bit-field.
2567 BODY is the SET-rtx to be altered.
2569 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2570 (Currently this is called only from function.c, and EQUIV_MEM
2574 optimize_bit_field (body, insn, equiv_mem)
2579 register rtx bitfield;
2582 enum machine_mode mode;
2584 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2585 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2586 bitfield = SET_DEST (body), destflag = 1;
2588 bitfield = SET_SRC (body), destflag = 0;
2590 /* First check that the field being stored has constant size and position
2591 and is in fact a byte or halfword suitably aligned. */
2593 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2594 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2595 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2597 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2599 register rtx memref = 0;
2601 /* Now check that the containing word is memory, not a register,
2602 and that it is safe to change the machine mode. */
2604 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2605 memref = XEXP (bitfield, 0);
2606 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2608 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2609 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2610 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2611 memref = SUBREG_REG (XEXP (bitfield, 0));
2612 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2614 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2615 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2618 && ! mode_dependent_address_p (XEXP (memref, 0))
2619 && ! MEM_VOLATILE_P (memref))
2621 /* Now adjust the address, first for any subreg'ing
2622 that we are now getting rid of,
2623 and then for which byte of the word is wanted. */
2625 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2628 /* Adjust OFFSET to count bits from low-address byte. */
2629 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2630 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2631 - offset - INTVAL (XEXP (bitfield, 1)));
2633 /* Adjust OFFSET to count bytes from low-address byte. */
2634 offset /= BITS_PER_UNIT;
2635 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2637 offset += SUBREG_WORD (XEXP (bitfield, 0)) * UNITS_PER_WORD;
2638 if (BYTES_BIG_ENDIAN)
2639 offset -= (MIN (UNITS_PER_WORD,
2640 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2641 - MIN (UNITS_PER_WORD,
2642 GET_MODE_SIZE (GET_MODE (memref))));
2646 memref = change_address (memref, mode,
2647 plus_constant (XEXP (memref, 0), offset));
2648 insns = get_insns ();
2650 emit_insns_before (insns, insn);
2652 /* Store this memory reference where
2653 we found the bit field reference. */
2657 validate_change (insn, &SET_DEST (body), memref, 1);
2658 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2660 rtx src = SET_SRC (body);
2661 while (GET_CODE (src) == SUBREG
2662 && SUBREG_WORD (src) == 0)
2663 src = SUBREG_REG (src);
2664 if (GET_MODE (src) != GET_MODE (memref))
2665 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2666 validate_change (insn, &SET_SRC (body), src, 1);
2668 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2669 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2670 /* This shouldn't happen because anything that didn't have
2671 one of these modes should have got converted explicitly
2672 and then referenced through a subreg.
2673 This is so because the original bit-field was
2674 handled by agg_mode and so its tree structure had
2675 the same mode that memref now has. */
2680 rtx dest = SET_DEST (body);
2682 while (GET_CODE (dest) == SUBREG
2683 && SUBREG_WORD (dest) == 0
2684 && (GET_MODE_CLASS (GET_MODE (dest))
2685 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2686 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2688 dest = SUBREG_REG (dest);
2690 validate_change (insn, &SET_DEST (body), dest, 1);
2692 if (GET_MODE (dest) == GET_MODE (memref))
2693 validate_change (insn, &SET_SRC (body), memref, 1);
2696 /* Convert the mem ref to the destination mode. */
2697 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2700 convert_move (newreg, memref,
2701 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2705 validate_change (insn, &SET_SRC (body), newreg, 1);
2709 /* See if we can convert this extraction or insertion into
2710 a simple move insn. We might not be able to do so if this
2711 was, for example, part of a PARALLEL.
2713 If we succeed, write out any needed conversions. If we fail,
2714 it is hard to guess why we failed, so don't do anything
2715 special; just let the optimization be suppressed. */
2717 if (apply_change_group () && seq)
2718 emit_insns_before (seq, insn);
2723 /* These routines are responsible for converting virtual register references
2724 to the actual hard register references once RTL generation is complete.
2726 The following four variables are used for communication between the
2727 routines. They contain the offsets of the virtual registers from their
2728 respective hard registers. */
2730 static int in_arg_offset;
2731 static int var_offset;
2732 static int dynamic_offset;
2733 static int out_arg_offset;
2734 static int cfa_offset;
2736 /* In most machines, the stack pointer register is equivalent to the bottom
2739 #ifndef STACK_POINTER_OFFSET
2740 #define STACK_POINTER_OFFSET 0
2743 /* If not defined, pick an appropriate default for the offset of dynamically
2744 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2745 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2747 #ifndef STACK_DYNAMIC_OFFSET
2749 #ifdef ACCUMULATE_OUTGOING_ARGS
2750 /* The bottom of the stack points to the actual arguments. If
2751 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2752 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2753 stack space for register parameters is not pushed by the caller, but
2754 rather part of the fixed stack areas and hence not included in
2755 `current_function_outgoing_args_size'. Nevertheless, we must allow
2756 for it when allocating stack dynamic objects. */
2758 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2759 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2760 (current_function_outgoing_args_size \
2761 + REG_PARM_STACK_SPACE (FNDECL) + (STACK_POINTER_OFFSET))
2764 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2765 (current_function_outgoing_args_size + (STACK_POINTER_OFFSET))
2769 #define STACK_DYNAMIC_OFFSET(FNDECL) STACK_POINTER_OFFSET
2773 /* On a few machines, the CFA coincides with the arg pointer. */
2775 #ifndef ARG_POINTER_CFA_OFFSET
2776 #define ARG_POINTER_CFA_OFFSET 0
2780 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just had
2781 its address taken. DECL is the decl for the object stored in the
2782 register, for later use if we do need to force REG into the stack.
2783 REG is overwritten by the MEM like in put_reg_into_stack. */
2786 gen_mem_addressof (reg, decl)
2790 tree type = TREE_TYPE (decl);
2791 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)), REGNO (reg));
2792 SET_ADDRESSOF_DECL (r, decl);
2793 /* If the original REG was a user-variable, then so is the REG whose
2794 address is being taken. */
2795 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2798 PUT_CODE (reg, MEM);
2799 PUT_MODE (reg, DECL_MODE (decl));
2800 MEM_VOLATILE_P (reg) = TREE_SIDE_EFFECTS (decl);
2801 MEM_SET_IN_STRUCT_P (reg, AGGREGATE_TYPE_P (type));
2802 MEM_ALIAS_SET (reg) = get_alias_set (decl);
2804 if (TREE_USED (decl) || DECL_INITIAL (decl) != 0)
2805 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type));
2810 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2813 flush_addressof (decl)
2816 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2817 && DECL_RTL (decl) != 0
2818 && GET_CODE (DECL_RTL (decl)) == MEM
2819 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2820 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2821 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0));
2824 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2827 put_addressof_into_stack (r)
2830 tree decl = ADDRESSOF_DECL (r);
2831 rtx reg = XEXP (r, 0);
2833 if (GET_CODE (reg) != REG)
2836 put_reg_into_stack (0, reg, TREE_TYPE (decl), GET_MODE (reg),
2837 DECL_MODE (decl), TREE_SIDE_EFFECTS (decl),
2838 ADDRESSOF_REGNO (r),
2839 TREE_USED (decl) || DECL_INITIAL (decl) != 0);
2842 /* List of replacements made below in purge_addressof_1 when creating
2843 bitfield insertions. */
2844 static rtx purge_addressof_replacements;
2846 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2847 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2851 purge_addressof_1 (loc, insn, force, store)
2861 /* Re-start here to avoid recursion in common cases. */
2868 code = GET_CODE (x);
2870 if (code == ADDRESSOF && GET_CODE (XEXP (x, 0)) == MEM)
2873 /* We must create a copy of the rtx because it was created by
2874 overwriting a REG rtx which is always shared. */
2875 rtx sub = copy_rtx (XEXP (XEXP (x, 0), 0));
2877 if (validate_change (insn, loc, sub, 0)
2878 || validate_replace_rtx (x, sub, insn))
2882 sub = force_operand (sub, NULL_RTX);
2883 if (! validate_change (insn, loc, sub, 0)
2884 && ! validate_replace_rtx (x, sub, insn))
2887 insns = gen_sequence ();
2889 emit_insn_before (insns, insn);
2892 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
2894 rtx sub = XEXP (XEXP (x, 0), 0);
2897 if (GET_CODE (sub) == MEM)
2899 sub2 = gen_rtx_MEM (GET_MODE (x), copy_rtx (XEXP (sub, 0)));
2900 MEM_COPY_ATTRIBUTES (sub2, sub);
2901 RTX_UNCHANGING_P (sub2) = RTX_UNCHANGING_P (sub);
2905 if (GET_CODE (sub) == REG
2906 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
2908 put_addressof_into_stack (XEXP (x, 0));
2911 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
2913 int size_x, size_sub;
2917 /* When processing REG_NOTES look at the list of
2918 replacements done on the insn to find the register that X
2922 for (tem = purge_addressof_replacements; tem != NULL_RTX;
2923 tem = XEXP (XEXP (tem, 1), 1))
2925 rtx y = XEXP (tem, 0);
2926 if (GET_CODE (y) == MEM
2927 && rtx_equal_p (XEXP (x, 0), XEXP (y, 0)))
2929 /* It can happen that the note may speak of things in
2930 a wider (or just different) mode than the code did.
2931 This is especially true of REG_RETVAL. */
2933 rtx z = XEXP (XEXP (tem, 1), 0);
2934 if (GET_MODE (x) != GET_MODE (y))
2936 if (GET_CODE (z) == SUBREG && SUBREG_WORD (z) == 0)
2939 /* ??? If we'd gotten into any of the really complex
2940 cases below, I'm not sure we can do a proper
2941 replacement. Might we be able to delete the
2942 note in some cases? */
2943 if (GET_MODE_SIZE (GET_MODE (x))
2944 < GET_MODE_SIZE (GET_MODE (y)))
2947 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
2948 && (GET_MODE_SIZE (GET_MODE (x))
2949 > GET_MODE_SIZE (GET_MODE (z))))
2951 /* This can occur as a result in invalid
2952 pointer casts, e.g. float f; ...
2953 *(long long int *)&f.
2954 ??? We could emit a warning here, but
2955 without a line number that wouldn't be
2957 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
2960 z = gen_lowpart (GET_MODE (x), z);
2968 /* There should always be such a replacement. */
2972 size_x = GET_MODE_BITSIZE (GET_MODE (x));
2973 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
2975 /* Don't even consider working with paradoxical subregs,
2976 or the moral equivalent seen here. */
2977 if (size_x <= size_sub
2978 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
2980 /* Do a bitfield insertion to mirror what would happen
2990 val = gen_reg_rtx (GET_MODE (x));
2991 if (! validate_change (insn, loc, val, 0))
2993 /* Discard the current sequence and put the
2994 ADDRESSOF on stack. */
2998 seq = gen_sequence ();
3000 emit_insn_before (seq, insn);
3003 store_bit_field (sub, size_x, 0, GET_MODE (x),
3004 val, GET_MODE_SIZE (GET_MODE (sub)),
3005 GET_MODE_SIZE (GET_MODE (sub)));
3007 /* Make sure to unshare any shared rtl that store_bit_field
3008 might have created. */
3009 for (p = get_insns(); p; p = NEXT_INSN (p))
3011 reset_used_flags (PATTERN (p));
3012 reset_used_flags (REG_NOTES (p));
3013 reset_used_flags (LOG_LINKS (p));
3015 unshare_all_rtl (get_insns ());
3017 seq = gen_sequence ();
3019 emit_insn_after (seq, insn);
3024 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3025 GET_MODE (x), GET_MODE (x),
3026 GET_MODE_SIZE (GET_MODE (sub)),
3027 GET_MODE_SIZE (GET_MODE (sub)));
3029 if (! validate_change (insn, loc, val, 0))
3031 /* Discard the current sequence and put the
3032 ADDRESSOF on stack. */
3037 seq = gen_sequence ();
3039 emit_insn_before (seq, insn);
3042 /* Remember the replacement so that the same one can be done
3043 on the REG_NOTES. */
3044 purge_addressof_replacements
3045 = gen_rtx_EXPR_LIST (VOIDmode, x,
3046 gen_rtx_EXPR_LIST (VOIDmode, val,
3047 purge_addressof_replacements));
3049 /* We replaced with a reg -- all done. */
3053 else if (validate_change (insn, loc, sub, 0))
3055 /* Remember the replacement so that the same one can be done
3056 on the REG_NOTES. */
3057 purge_addressof_replacements
3058 = gen_rtx_EXPR_LIST (VOIDmode, x,
3059 gen_rtx_EXPR_LIST (VOIDmode, sub,
3060 purge_addressof_replacements));
3064 /* else give up and put it into the stack */
3066 else if (code == ADDRESSOF)
3068 put_addressof_into_stack (x);
3071 else if (code == SET)
3073 purge_addressof_1 (&SET_DEST (x), insn, force, 1);
3074 purge_addressof_1 (&SET_SRC (x), insn, force, 0);
3078 /* Scan all subexpressions. */
3079 fmt = GET_RTX_FORMAT (code);
3080 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3083 purge_addressof_1 (&XEXP (x, i), insn, force, 0);
3084 else if (*fmt == 'E')
3085 for (j = 0; j < XVECLEN (x, i); j++)
3086 purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0);
3090 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3091 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3095 purge_addressof (insns)
3099 for (insn = insns; insn; insn = NEXT_INSN (insn))
3100 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3101 || GET_CODE (insn) == CALL_INSN)
3103 purge_addressof_1 (&PATTERN (insn), insn,
3104 asm_noperands (PATTERN (insn)) > 0, 0);
3105 purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0);
3107 purge_addressof_replacements = 0;
3110 /* Pass through the INSNS of function FNDECL and convert virtual register
3111 references to hard register references. */
3114 instantiate_virtual_regs (fndecl, insns)
3121 /* Compute the offsets to use for this function. */
3122 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3123 var_offset = STARTING_FRAME_OFFSET;
3124 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3125 out_arg_offset = STACK_POINTER_OFFSET;
3126 cfa_offset = ARG_POINTER_CFA_OFFSET;
3128 /* Scan all variables and parameters of this function. For each that is
3129 in memory, instantiate all virtual registers if the result is a valid
3130 address. If not, we do it later. That will handle most uses of virtual
3131 regs on many machines. */
3132 instantiate_decls (fndecl, 1);
3134 /* Initialize recognition, indicating that volatile is OK. */
3137 /* Scan through all the insns, instantiating every virtual register still
3139 for (insn = insns; insn; insn = NEXT_INSN (insn))
3140 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3141 || GET_CODE (insn) == CALL_INSN)
3143 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3144 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3147 /* Instantiate the stack slots for the parm registers, for later use in
3148 addressof elimination. */
3149 for (i = 0; i < max_parm_reg; ++i)
3150 if (parm_reg_stack_loc[i])
3151 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3153 /* Now instantiate the remaining register equivalences for debugging info.
3154 These will not be valid addresses. */
3155 instantiate_decls (fndecl, 0);
3157 /* Indicate that, from now on, assign_stack_local should use
3158 frame_pointer_rtx. */
3159 virtuals_instantiated = 1;
3162 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3163 all virtual registers in their DECL_RTL's.
3165 If VALID_ONLY, do this only if the resulting address is still valid.
3166 Otherwise, always do it. */
3169 instantiate_decls (fndecl, valid_only)
3175 if (DECL_SAVED_INSNS (fndecl))
3176 /* When compiling an inline function, the obstack used for
3177 rtl allocation is the maybepermanent_obstack. Calling
3178 `resume_temporary_allocation' switches us back to that
3179 obstack while we process this function's parameters. */
3180 resume_temporary_allocation ();
3182 /* Process all parameters of the function. */
3183 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3185 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3187 instantiate_decl (DECL_RTL (decl), size, valid_only);
3189 /* If the parameter was promoted, then the incoming RTL mode may be
3190 larger than the declared type size. We must use the larger of
3192 size = MAX (GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl))), size);
3193 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3196 /* Now process all variables defined in the function or its subblocks. */
3197 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3199 if (DECL_INLINE (fndecl) || DECL_DEFER_OUTPUT (fndecl))
3201 /* Save all rtl allocated for this function by raising the
3202 high-water mark on the maybepermanent_obstack. */
3204 /* All further rtl allocation is now done in the current_obstack. */
3205 rtl_in_current_obstack ();
3209 /* Subroutine of instantiate_decls: Process all decls in the given
3210 BLOCK node and all its subblocks. */
3213 instantiate_decls_1 (let, valid_only)
3219 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3220 instantiate_decl (DECL_RTL (t), int_size_in_bytes (TREE_TYPE (t)),
3223 /* Process all subblocks. */
3224 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3225 instantiate_decls_1 (t, valid_only);
3228 /* Subroutine of the preceding procedures: Given RTL representing a
3229 decl and the size of the object, do any instantiation required.
3231 If VALID_ONLY is non-zero, it means that the RTL should only be
3232 changed if the new address is valid. */
3235 instantiate_decl (x, size, valid_only)
3240 enum machine_mode mode;
3243 /* If this is not a MEM, no need to do anything. Similarly if the
3244 address is a constant or a register that is not a virtual register. */
3246 if (x == 0 || GET_CODE (x) != MEM)
3250 if (CONSTANT_P (addr)
3251 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3252 || (GET_CODE (addr) == REG
3253 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3254 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3257 /* If we should only do this if the address is valid, copy the address.
3258 We need to do this so we can undo any changes that might make the
3259 address invalid. This copy is unfortunate, but probably can't be
3263 addr = copy_rtx (addr);
3265 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3269 /* Now verify that the resulting address is valid for every integer or
3270 floating-point mode up to and including SIZE bytes long. We do this
3271 since the object might be accessed in any mode and frame addresses
3274 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3275 mode != VOIDmode && GET_MODE_SIZE (mode) <= size;
3276 mode = GET_MODE_WIDER_MODE (mode))
3277 if (! memory_address_p (mode, addr))
3280 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3281 mode != VOIDmode && GET_MODE_SIZE (mode) <= size;
3282 mode = GET_MODE_WIDER_MODE (mode))
3283 if (! memory_address_p (mode, addr))
3287 /* Put back the address now that we have updated it and we either know
3288 it is valid or we don't care whether it is valid. */
3293 /* Given a pointer to a piece of rtx and an optional pointer to the
3294 containing object, instantiate any virtual registers present in it.
3296 If EXTRA_INSNS, we always do the replacement and generate
3297 any extra insns before OBJECT. If it zero, we do nothing if replacement
3300 Return 1 if we either had nothing to do or if we were able to do the
3301 needed replacement. Return 0 otherwise; we only return zero if
3302 EXTRA_INSNS is zero.
3304 We first try some simple transformations to avoid the creation of extra
3308 instantiate_virtual_regs_1 (loc, object, extra_insns)
3316 HOST_WIDE_INT offset;
3322 /* Re-start here to avoid recursion in common cases. */
3329 code = GET_CODE (x);
3331 /* Check for some special cases. */
3348 /* We are allowed to set the virtual registers. This means that
3349 the actual register should receive the source minus the
3350 appropriate offset. This is used, for example, in the handling
3351 of non-local gotos. */
3352 if (SET_DEST (x) == virtual_incoming_args_rtx)
3353 new = arg_pointer_rtx, offset = - in_arg_offset;
3354 else if (SET_DEST (x) == virtual_stack_vars_rtx)
3355 new = frame_pointer_rtx, offset = - var_offset;
3356 else if (SET_DEST (x) == virtual_stack_dynamic_rtx)
3357 new = stack_pointer_rtx, offset = - dynamic_offset;
3358 else if (SET_DEST (x) == virtual_outgoing_args_rtx)
3359 new = stack_pointer_rtx, offset = - out_arg_offset;
3360 else if (SET_DEST (x) == virtual_cfa_rtx)
3361 new = arg_pointer_rtx, offset = - cfa_offset;
3365 /* The only valid sources here are PLUS or REG. Just do
3366 the simplest possible thing to handle them. */
3367 if (GET_CODE (SET_SRC (x)) != REG
3368 && GET_CODE (SET_SRC (x)) != PLUS)
3372 if (GET_CODE (SET_SRC (x)) != REG)
3373 temp = force_operand (SET_SRC (x), NULL_RTX);
3376 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3380 emit_insns_before (seq, object);
3383 if (! validate_change (object, &SET_SRC (x), temp, 0)
3390 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3395 /* Handle special case of virtual register plus constant. */
3396 if (CONSTANT_P (XEXP (x, 1)))
3398 rtx old, new_offset;
3400 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3401 if (GET_CODE (XEXP (x, 0)) == PLUS)
3403 rtx inner = XEXP (XEXP (x, 0), 0);
3405 if (inner == virtual_incoming_args_rtx)
3406 new = arg_pointer_rtx, offset = in_arg_offset;
3407 else if (inner == virtual_stack_vars_rtx)
3408 new = frame_pointer_rtx, offset = var_offset;
3409 else if (inner == virtual_stack_dynamic_rtx)
3410 new = stack_pointer_rtx, offset = dynamic_offset;
3411 else if (inner == virtual_outgoing_args_rtx)
3412 new = stack_pointer_rtx, offset = out_arg_offset;
3413 else if (inner == virtual_cfa_rtx)
3414 new = arg_pointer_rtx, offset = cfa_offset;
3421 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3423 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3426 else if (XEXP (x, 0) == virtual_incoming_args_rtx)
3427 new = arg_pointer_rtx, offset = in_arg_offset;
3428 else if (XEXP (x, 0) == virtual_stack_vars_rtx)
3429 new = frame_pointer_rtx, offset = var_offset;
3430 else if (XEXP (x, 0) == virtual_stack_dynamic_rtx)
3431 new = stack_pointer_rtx, offset = dynamic_offset;
3432 else if (XEXP (x, 0) == virtual_outgoing_args_rtx)
3433 new = stack_pointer_rtx, offset = out_arg_offset;
3434 else if (XEXP (x, 0) == virtual_cfa_rtx)
3435 new = arg_pointer_rtx, offset = cfa_offset;
3438 /* We know the second operand is a constant. Unless the
3439 first operand is a REG (which has been already checked),
3440 it needs to be checked. */
3441 if (GET_CODE (XEXP (x, 0)) != REG)
3449 new_offset = plus_constant (XEXP (x, 1), offset);
3451 /* If the new constant is zero, try to replace the sum with just
3453 if (new_offset == const0_rtx
3454 && validate_change (object, loc, new, 0))
3457 /* Next try to replace the register and new offset.
3458 There are two changes to validate here and we can't assume that
3459 in the case of old offset equals new just changing the register
3460 will yield a valid insn. In the interests of a little efficiency,
3461 however, we only call validate change once (we don't queue up the
3462 changes and then call apply_change_group). */
3466 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3467 : (XEXP (x, 0) = new,
3468 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3476 /* Otherwise copy the new constant into a register and replace
3477 constant with that register. */
3478 temp = gen_reg_rtx (Pmode);
3480 if (validate_change (object, &XEXP (x, 1), temp, 0))
3481 emit_insn_before (gen_move_insn (temp, new_offset), object);
3484 /* If that didn't work, replace this expression with a
3485 register containing the sum. */
3488 new = gen_rtx_PLUS (Pmode, new, new_offset);
3491 temp = force_operand (new, NULL_RTX);
3495 emit_insns_before (seq, object);
3496 if (! validate_change (object, loc, temp, 0)
3497 && ! validate_replace_rtx (x, temp, object))
3505 /* Fall through to generic two-operand expression case. */
3511 case DIV: case UDIV:
3512 case MOD: case UMOD:
3513 case AND: case IOR: case XOR:
3514 case ROTATERT: case ROTATE:
3515 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3517 case GE: case GT: case GEU: case GTU:
3518 case LE: case LT: case LEU: case LTU:
3519 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3520 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3525 /* Most cases of MEM that convert to valid addresses have already been
3526 handled by our scan of decls. The only special handling we
3527 need here is to make a copy of the rtx to ensure it isn't being
3528 shared if we have to change it to a pseudo.
3530 If the rtx is a simple reference to an address via a virtual register,
3531 it can potentially be shared. In such cases, first try to make it
3532 a valid address, which can also be shared. Otherwise, copy it and
3535 First check for common cases that need no processing. These are
3536 usually due to instantiation already being done on a previous instance
3540 if (CONSTANT_ADDRESS_P (temp)
3541 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3542 || temp == arg_pointer_rtx
3544 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3545 || temp == hard_frame_pointer_rtx
3547 || temp == frame_pointer_rtx)
3550 if (GET_CODE (temp) == PLUS
3551 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3552 && (XEXP (temp, 0) == frame_pointer_rtx
3553 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3554 || XEXP (temp, 0) == hard_frame_pointer_rtx
3556 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3557 || XEXP (temp, 0) == arg_pointer_rtx
3562 if (temp == virtual_stack_vars_rtx
3563 || temp == virtual_incoming_args_rtx
3564 || (GET_CODE (temp) == PLUS
3565 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3566 && (XEXP (temp, 0) == virtual_stack_vars_rtx
3567 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
3569 /* This MEM may be shared. If the substitution can be done without
3570 the need to generate new pseudos, we want to do it in place
3571 so all copies of the shared rtx benefit. The call below will
3572 only make substitutions if the resulting address is still
3575 Note that we cannot pass X as the object in the recursive call
3576 since the insn being processed may not allow all valid
3577 addresses. However, if we were not passed on object, we can
3578 only modify X without copying it if X will have a valid
3581 ??? Also note that this can still lose if OBJECT is an insn that
3582 has less restrictions on an address that some other insn.
3583 In that case, we will modify the shared address. This case
3584 doesn't seem very likely, though. One case where this could
3585 happen is in the case of a USE or CLOBBER reference, but we
3586 take care of that below. */
3588 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
3589 object ? object : x, 0))
3592 /* Otherwise make a copy and process that copy. We copy the entire
3593 RTL expression since it might be a PLUS which could also be
3595 *loc = x = copy_rtx (x);
3598 /* Fall through to generic unary operation case. */
3600 case STRICT_LOW_PART:
3602 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
3603 case SIGN_EXTEND: case ZERO_EXTEND:
3604 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
3605 case FLOAT: case FIX:
3606 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
3610 /* These case either have just one operand or we know that we need not
3611 check the rest of the operands. */
3617 /* If the operand is a MEM, see if the change is a valid MEM. If not,
3618 go ahead and make the invalid one, but do it to a copy. For a REG,
3619 just make the recursive call, since there's no chance of a problem. */
3621 if ((GET_CODE (XEXP (x, 0)) == MEM
3622 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
3624 || (GET_CODE (XEXP (x, 0)) == REG
3625 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
3628 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
3633 /* Try to replace with a PLUS. If that doesn't work, compute the sum
3634 in front of this insn and substitute the temporary. */
3635 if (x == virtual_incoming_args_rtx)
3636 new = arg_pointer_rtx, offset = in_arg_offset;
3637 else if (x == virtual_stack_vars_rtx)
3638 new = frame_pointer_rtx, offset = var_offset;
3639 else if (x == virtual_stack_dynamic_rtx)
3640 new = stack_pointer_rtx, offset = dynamic_offset;
3641 else if (x == virtual_outgoing_args_rtx)
3642 new = stack_pointer_rtx, offset = out_arg_offset;
3643 else if (x == virtual_cfa_rtx)
3644 new = arg_pointer_rtx, offset = cfa_offset;
3648 temp = plus_constant (new, offset);
3649 if (!validate_change (object, loc, temp, 0))
3655 temp = force_operand (temp, NULL_RTX);
3659 emit_insns_before (seq, object);
3660 if (! validate_change (object, loc, temp, 0)
3661 && ! validate_replace_rtx (x, temp, object))
3669 if (GET_CODE (XEXP (x, 0)) == REG)
3672 else if (GET_CODE (XEXP (x, 0)) == MEM)
3674 /* If we have a (addressof (mem ..)), do any instantiation inside
3675 since we know we'll be making the inside valid when we finally
3676 remove the ADDRESSOF. */
3677 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
3686 /* Scan all subexpressions. */
3687 fmt = GET_RTX_FORMAT (code);
3688 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3691 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
3694 else if (*fmt == 'E')
3695 for (j = 0; j < XVECLEN (x, i); j++)
3696 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
3703 /* Optimization: assuming this function does not receive nonlocal gotos,
3704 delete the handlers for such, as well as the insns to establish
3705 and disestablish them. */
3711 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3713 /* Delete the handler by turning off the flag that would
3714 prevent jump_optimize from deleting it.
3715 Also permit deletion of the nonlocal labels themselves
3716 if nothing local refers to them. */
3717 if (GET_CODE (insn) == CODE_LABEL)
3721 LABEL_PRESERVE_P (insn) = 0;
3723 /* Remove it from the nonlocal_label list, to avoid confusing
3725 for (t = nonlocal_labels, last_t = 0; t;
3726 last_t = t, t = TREE_CHAIN (t))
3727 if (DECL_RTL (TREE_VALUE (t)) == insn)
3732 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
3734 TREE_CHAIN (last_t) = TREE_CHAIN (t);
3737 if (GET_CODE (insn) == INSN)
3741 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
3742 if (reg_mentioned_p (t, PATTERN (insn)))
3748 || (nonlocal_goto_stack_level != 0
3749 && reg_mentioned_p (nonlocal_goto_stack_level,
3756 /* Return a list (chain of EXPR_LIST nodes) for the nonlocal labels
3757 of the current function. */
3760 nonlocal_label_rtx_list ()
3765 for (t = nonlocal_labels; t; t = TREE_CHAIN (t))
3766 x = gen_rtx_EXPR_LIST (VOIDmode, label_rtx (TREE_VALUE (t)), x);
3771 /* Output a USE for any register use in RTL.
3772 This is used with -noreg to mark the extent of lifespan
3773 of any registers used in a user-visible variable's DECL_RTL. */
3779 if (GET_CODE (rtl) == REG)
3780 /* This is a register variable. */
3781 emit_insn (gen_rtx_USE (VOIDmode, rtl));
3782 else if (GET_CODE (rtl) == MEM
3783 && GET_CODE (XEXP (rtl, 0)) == REG
3784 && (REGNO (XEXP (rtl, 0)) < FIRST_VIRTUAL_REGISTER
3785 || REGNO (XEXP (rtl, 0)) > LAST_VIRTUAL_REGISTER)
3786 && XEXP (rtl, 0) != current_function_internal_arg_pointer)
3787 /* This is a variable-sized structure. */
3788 emit_insn (gen_rtx_USE (VOIDmode, XEXP (rtl, 0)));
3791 /* Like use_variable except that it outputs the USEs after INSN
3792 instead of at the end of the insn-chain. */
3795 use_variable_after (rtl, insn)
3798 if (GET_CODE (rtl) == REG)
3799 /* This is a register variable. */
3800 emit_insn_after (gen_rtx_USE (VOIDmode, rtl), insn);
3801 else if (GET_CODE (rtl) == MEM
3802 && GET_CODE (XEXP (rtl, 0)) == REG
3803 && (REGNO (XEXP (rtl, 0)) < FIRST_VIRTUAL_REGISTER
3804 || REGNO (XEXP (rtl, 0)) > LAST_VIRTUAL_REGISTER)
3805 && XEXP (rtl, 0) != current_function_internal_arg_pointer)
3806 /* This is a variable-sized structure. */
3807 emit_insn_after (gen_rtx_USE (VOIDmode, XEXP (rtl, 0)), insn);
3813 return max_parm_reg;
3816 /* Return the first insn following those generated by `assign_parms'. */
3819 get_first_nonparm_insn ()
3822 return NEXT_INSN (last_parm_insn);
3823 return get_insns ();
3826 /* Return the first NOTE_INSN_BLOCK_BEG note in the function.
3827 Crash if there is none. */
3830 get_first_block_beg ()
3832 register rtx searcher;
3833 register rtx insn = get_first_nonparm_insn ();
3835 for (searcher = insn; searcher; searcher = NEXT_INSN (searcher))
3836 if (GET_CODE (searcher) == NOTE
3837 && NOTE_LINE_NUMBER (searcher) == NOTE_INSN_BLOCK_BEG)
3840 abort (); /* Invalid call to this function. (See comments above.) */
3844 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
3845 This means a type for which function calls must pass an address to the
3846 function or get an address back from the function.
3847 EXP may be a type node or an expression (whose type is tested). */
3850 aggregate_value_p (exp)
3853 int i, regno, nregs;
3856 if (TREE_CODE_CLASS (TREE_CODE (exp)) == 't')
3859 type = TREE_TYPE (exp);
3861 if (RETURN_IN_MEMORY (type))
3863 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
3864 and thus can't be returned in registers. */
3865 if (TREE_ADDRESSABLE (type))
3867 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
3869 /* Make sure we have suitable call-clobbered regs to return
3870 the value in; if not, we must return it in memory. */
3871 reg = hard_function_value (type, 0);
3873 /* If we have something other than a REG (e.g. a PARALLEL), then assume
3875 if (GET_CODE (reg) != REG)
3878 regno = REGNO (reg);
3879 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
3880 for (i = 0; i < nregs; i++)
3881 if (! call_used_regs[regno + i])
3886 /* Assign RTL expressions to the function's parameters.
3887 This may involve copying them into registers and using
3888 those registers as the RTL for them.
3890 If SECOND_TIME is non-zero it means that this function is being
3891 called a second time. This is done by integrate.c when a function's
3892 compilation is deferred. We need to come back here in case the
3893 FUNCTION_ARG macro computes items needed for the rest of the compilation
3894 (such as changing which registers are fixed or caller-saved). But suppress
3895 writing any insns or setting DECL_RTL of anything in this case. */
3898 assign_parms (fndecl, second_time)
3903 register rtx entry_parm = 0;
3904 register rtx stack_parm = 0;
3905 CUMULATIVE_ARGS args_so_far;
3906 enum machine_mode promoted_mode, passed_mode;
3907 enum machine_mode nominal_mode, promoted_nominal_mode;
3909 /* Total space needed so far for args on the stack,
3910 given as a constant and a tree-expression. */
3911 struct args_size stack_args_size;
3912 tree fntype = TREE_TYPE (fndecl);
3913 tree fnargs = DECL_ARGUMENTS (fndecl);
3914 /* This is used for the arg pointer when referring to stack args. */
3915 rtx internal_arg_pointer;
3916 /* This is a dummy PARM_DECL that we used for the function result if
3917 the function returns a structure. */
3918 tree function_result_decl = 0;
3919 int varargs_setup = 0;
3920 rtx conversion_insns = 0;
3922 /* Nonzero if the last arg is named `__builtin_va_alist',
3923 which is used on some machines for old-fashioned non-ANSI varargs.h;
3924 this should be stuck onto the stack as if it had arrived there. */
3926 = (current_function_varargs
3928 && (parm = tree_last (fnargs)) != 0
3930 && (! strcmp (IDENTIFIER_POINTER (DECL_NAME (parm)),
3931 "__builtin_va_alist")));
3933 /* Nonzero if function takes extra anonymous args.
3934 This means the last named arg must be on the stack
3935 right before the anonymous ones. */
3937 = (TYPE_ARG_TYPES (fntype) != 0
3938 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
3939 != void_type_node));
3941 current_function_stdarg = stdarg;
3943 /* If the reg that the virtual arg pointer will be translated into is
3944 not a fixed reg or is the stack pointer, make a copy of the virtual
3945 arg pointer, and address parms via the copy. The frame pointer is
3946 considered fixed even though it is not marked as such.
3948 The second time through, simply use ap to avoid generating rtx. */
3950 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
3951 || ! (fixed_regs[ARG_POINTER_REGNUM]
3952 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM))
3954 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
3956 internal_arg_pointer = virtual_incoming_args_rtx;
3957 current_function_internal_arg_pointer = internal_arg_pointer;
3959 stack_args_size.constant = 0;
3960 stack_args_size.var = 0;
3962 /* If struct value address is treated as the first argument, make it so. */
3963 if (aggregate_value_p (DECL_RESULT (fndecl))
3964 && ! current_function_returns_pcc_struct
3965 && struct_value_incoming_rtx == 0)
3967 tree type = build_pointer_type (TREE_TYPE (fntype));
3969 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
3971 DECL_ARG_TYPE (function_result_decl) = type;
3972 TREE_CHAIN (function_result_decl) = fnargs;
3973 fnargs = function_result_decl;
3976 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
3977 parm_reg_stack_loc = (rtx *) savealloc (max_parm_reg * sizeof (rtx));
3978 bzero ((char *) parm_reg_stack_loc, max_parm_reg * sizeof (rtx));
3980 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
3981 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
3983 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, 0);
3986 /* We haven't yet found an argument that we must push and pretend the
3988 current_function_pretend_args_size = 0;
3990 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
3992 int aggregate = AGGREGATE_TYPE_P (TREE_TYPE (parm));
3993 struct args_size stack_offset;
3994 struct args_size arg_size;
3995 int passed_pointer = 0;
3996 int did_conversion = 0;
3997 tree passed_type = DECL_ARG_TYPE (parm);
3998 tree nominal_type = TREE_TYPE (parm);
4000 /* Set LAST_NAMED if this is last named arg before some
4002 int last_named = ((TREE_CHAIN (parm) == 0
4003 || DECL_NAME (TREE_CHAIN (parm)) == 0)
4004 && (stdarg || current_function_varargs));
4005 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4006 most machines, if this is a varargs/stdarg function, then we treat
4007 the last named arg as if it were anonymous too. */
4008 int named_arg = STRICT_ARGUMENT_NAMING ? 1 : ! last_named;
4010 if (TREE_TYPE (parm) == error_mark_node
4011 /* This can happen after weird syntax errors
4012 or if an enum type is defined among the parms. */
4013 || TREE_CODE (parm) != PARM_DECL
4014 || passed_type == NULL)
4016 DECL_INCOMING_RTL (parm) = DECL_RTL (parm)
4017 = gen_rtx_MEM (BLKmode, const0_rtx);
4018 TREE_USED (parm) = 1;
4022 /* For varargs.h function, save info about regs and stack space
4023 used by the individual args, not including the va_alist arg. */
4024 if (hide_last_arg && last_named)
4025 current_function_args_info = args_so_far;
4027 /* Find mode of arg as it is passed, and mode of arg
4028 as it should be during execution of this function. */
4029 passed_mode = TYPE_MODE (passed_type);
4030 nominal_mode = TYPE_MODE (nominal_type);
4032 /* If the parm's mode is VOID, its value doesn't matter,
4033 and avoid the usual things like emit_move_insn that could crash. */
4034 if (nominal_mode == VOIDmode)
4036 DECL_INCOMING_RTL (parm) = DECL_RTL (parm) = const0_rtx;
4040 /* If the parm is to be passed as a transparent union, use the
4041 type of the first field for the tests below. We have already
4042 verified that the modes are the same. */
4043 if (DECL_TRANSPARENT_UNION (parm)
4044 || TYPE_TRANSPARENT_UNION (passed_type))
4045 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4047 /* See if this arg was passed by invisible reference. It is if
4048 it is an object whose size depends on the contents of the
4049 object itself or if the machine requires these objects be passed
4052 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
4053 && contains_placeholder_p (TYPE_SIZE (passed_type)))
4054 || TREE_ADDRESSABLE (passed_type)
4055 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4056 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4057 passed_type, named_arg)
4061 passed_type = nominal_type = build_pointer_type (passed_type);
4063 passed_mode = nominal_mode = Pmode;
4066 promoted_mode = passed_mode;
4068 #ifdef PROMOTE_FUNCTION_ARGS
4069 /* Compute the mode in which the arg is actually extended to. */
4070 unsignedp = TREE_UNSIGNED (passed_type);
4071 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4074 /* Let machine desc say which reg (if any) the parm arrives in.
4075 0 means it arrives on the stack. */
4076 #ifdef FUNCTION_INCOMING_ARG
4077 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4078 passed_type, named_arg);
4080 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4081 passed_type, named_arg);
4084 if (entry_parm == 0)
4085 promoted_mode = passed_mode;
4087 #ifdef SETUP_INCOMING_VARARGS
4088 /* If this is the last named parameter, do any required setup for
4089 varargs or stdargs. We need to know about the case of this being an
4090 addressable type, in which case we skip the registers it
4091 would have arrived in.
4093 For stdargs, LAST_NAMED will be set for two parameters, the one that
4094 is actually the last named, and the dummy parameter. We only
4095 want to do this action once.
4097 Also, indicate when RTL generation is to be suppressed. */
4098 if (last_named && !varargs_setup)
4100 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
4101 current_function_pretend_args_size,
4107 /* Determine parm's home in the stack,
4108 in case it arrives in the stack or we should pretend it did.
4110 Compute the stack position and rtx where the argument arrives
4113 There is one complexity here: If this was a parameter that would
4114 have been passed in registers, but wasn't only because it is
4115 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4116 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4117 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4118 0 as it was the previous time. */
4120 locate_and_pad_parm (nominal_mode, passed_type,
4121 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4124 #ifdef FUNCTION_INCOMING_ARG
4125 FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4128 || varargs_setup)) != 0,
4130 FUNCTION_ARG (args_so_far, promoted_mode,
4132 named_arg || varargs_setup) != 0,
4135 fndecl, &stack_args_size, &stack_offset, &arg_size);
4139 rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
4141 if (offset_rtx == const0_rtx)
4142 stack_parm = gen_rtx_MEM (nominal_mode, internal_arg_pointer);
4144 stack_parm = gen_rtx_MEM (nominal_mode,
4145 gen_rtx_PLUS (Pmode,
4146 internal_arg_pointer,
4149 /* If this is a memory ref that contains aggregate components,
4150 mark it as such for cse and loop optimize. Likewise if it
4152 MEM_SET_IN_STRUCT_P (stack_parm, aggregate);
4153 RTX_UNCHANGING_P (stack_parm) = TREE_READONLY (parm);
4154 MEM_ALIAS_SET (stack_parm) = get_alias_set (parm);
4157 /* If this parameter was passed both in registers and in the stack,
4158 use the copy on the stack. */
4159 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4162 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4163 /* If this parm was passed part in regs and part in memory,
4164 pretend it arrived entirely in memory
4165 by pushing the register-part onto the stack.
4167 In the special case of a DImode or DFmode that is split,
4168 we could put it together in a pseudoreg directly,
4169 but for now that's not worth bothering with. */
4173 int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4174 passed_type, named_arg);
4178 current_function_pretend_args_size
4179 = (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
4180 / (PARM_BOUNDARY / BITS_PER_UNIT)
4181 * (PARM_BOUNDARY / BITS_PER_UNIT));
4185 /* Handle calls that pass values in multiple non-contiguous
4186 locations. The Irix 6 ABI has examples of this. */
4187 if (GET_CODE (entry_parm) == PARALLEL)
4188 emit_group_store (validize_mem (stack_parm), entry_parm,
4189 int_size_in_bytes (TREE_TYPE (parm)),
4190 (TYPE_ALIGN (TREE_TYPE (parm))
4193 move_block_from_reg (REGNO (entry_parm),
4194 validize_mem (stack_parm), nregs,
4195 int_size_in_bytes (TREE_TYPE (parm)));
4197 entry_parm = stack_parm;
4202 /* If we didn't decide this parm came in a register,
4203 by default it came on the stack. */
4204 if (entry_parm == 0)
4205 entry_parm = stack_parm;
4207 /* Record permanently how this parm was passed. */
4209 DECL_INCOMING_RTL (parm) = entry_parm;
4211 /* If there is actually space on the stack for this parm,
4212 count it in stack_args_size; otherwise set stack_parm to 0
4213 to indicate there is no preallocated stack slot for the parm. */
4215 if (entry_parm == stack_parm
4216 || (GET_CODE (entry_parm) == PARALLEL
4217 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4218 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4219 /* On some machines, even if a parm value arrives in a register
4220 there is still an (uninitialized) stack slot allocated for it.
4222 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4223 whether this parameter already has a stack slot allocated,
4224 because an arg block exists only if current_function_args_size
4225 is larger than some threshold, and we haven't calculated that
4226 yet. So, for now, we just assume that stack slots never exist
4228 || REG_PARM_STACK_SPACE (fndecl) > 0
4232 stack_args_size.constant += arg_size.constant;
4234 ADD_PARM_SIZE (stack_args_size, arg_size.var);
4237 /* No stack slot was pushed for this parm. */
4240 /* Update info on where next arg arrives in registers. */
4242 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4243 passed_type, named_arg);
4245 /* If this is our second time through, we are done with this parm. */
4249 /* If we can't trust the parm stack slot to be aligned enough
4250 for its ultimate type, don't use that slot after entry.
4251 We'll make another stack slot, if we need one. */
4253 int thisparm_boundary
4254 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4256 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4260 /* If parm was passed in memory, and we need to convert it on entry,
4261 don't store it back in that same slot. */
4263 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4267 /* Now adjust STACK_PARM to the mode and precise location
4268 where this parameter should live during execution,
4269 if we discover that it must live in the stack during execution.
4270 To make debuggers happier on big-endian machines, we store
4271 the value in the last bytes of the space available. */
4273 if (nominal_mode != BLKmode && nominal_mode != passed_mode
4278 if (BYTES_BIG_ENDIAN
4279 && GET_MODE_SIZE (nominal_mode) < UNITS_PER_WORD)
4280 stack_offset.constant += (GET_MODE_SIZE (passed_mode)
4281 - GET_MODE_SIZE (nominal_mode));
4283 offset_rtx = ARGS_SIZE_RTX (stack_offset);
4284 if (offset_rtx == const0_rtx)
4285 stack_parm = gen_rtx_MEM (nominal_mode, internal_arg_pointer);
4287 stack_parm = gen_rtx_MEM (nominal_mode,
4288 gen_rtx_PLUS (Pmode,
4289 internal_arg_pointer,
4292 /* If this is a memory ref that contains aggregate components,
4293 mark it as such for cse and loop optimize. */
4294 MEM_SET_IN_STRUCT_P (stack_parm, aggregate);
4299 /* We need this "use" info, because the gcc-register->stack-register
4300 converter in reg-stack.c needs to know which registers are active
4301 at the start of the function call. The actual parameter loading
4302 instructions are not always available then anymore, since they might
4303 have been optimised away. */
4305 if (GET_CODE (entry_parm) == REG && !(hide_last_arg && last_named))
4306 emit_insn (gen_rtx_USE (GET_MODE (entry_parm), entry_parm));
4309 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4310 in the mode in which it arrives.
4311 STACK_PARM is an RTX for a stack slot where the parameter can live
4312 during the function (in case we want to put it there).
4313 STACK_PARM is 0 if no stack slot was pushed for it.
4315 Now output code if necessary to convert ENTRY_PARM to
4316 the type in which this function declares it,
4317 and store that result in an appropriate place,
4318 which may be a pseudo reg, may be STACK_PARM,
4319 or may be a local stack slot if STACK_PARM is 0.
4321 Set DECL_RTL to that place. */
4323 if (nominal_mode == BLKmode || GET_CODE (entry_parm) == PARALLEL)
4325 /* If a BLKmode arrives in registers, copy it to a stack slot.
4326 Handle calls that pass values in multiple non-contiguous
4327 locations. The Irix 6 ABI has examples of this. */
4328 if (GET_CODE (entry_parm) == REG
4329 || GET_CODE (entry_parm) == PARALLEL)
4332 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
4335 /* Note that we will be storing an integral number of words.
4336 So we have to be careful to ensure that we allocate an
4337 integral number of words. We do this below in the
4338 assign_stack_local if space was not allocated in the argument
4339 list. If it was, this will not work if PARM_BOUNDARY is not
4340 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4341 if it becomes a problem. */
4343 if (stack_parm == 0)
4346 = assign_stack_local (GET_MODE (entry_parm),
4349 /* If this is a memory ref that contains aggregate
4350 components, mark it as such for cse and loop optimize. */
4351 MEM_SET_IN_STRUCT_P (stack_parm, aggregate);
4354 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4357 if (TREE_READONLY (parm))
4358 RTX_UNCHANGING_P (stack_parm) = 1;
4360 /* Handle calls that pass values in multiple non-contiguous
4361 locations. The Irix 6 ABI has examples of this. */
4362 if (GET_CODE (entry_parm) == PARALLEL)
4363 emit_group_store (validize_mem (stack_parm), entry_parm,
4364 int_size_in_bytes (TREE_TYPE (parm)),
4365 (TYPE_ALIGN (TREE_TYPE (parm))
4368 move_block_from_reg (REGNO (entry_parm),
4369 validize_mem (stack_parm),
4370 size_stored / UNITS_PER_WORD,
4371 int_size_in_bytes (TREE_TYPE (parm)));
4373 DECL_RTL (parm) = stack_parm;
4375 else if (! ((obey_regdecls && ! DECL_REGISTER (parm)
4376 && ! DECL_INLINE (fndecl))
4377 /* layout_decl may set this. */
4378 || TREE_ADDRESSABLE (parm)
4379 || TREE_SIDE_EFFECTS (parm)
4380 /* If -ffloat-store specified, don't put explicit
4381 float variables into registers. */
4382 || (flag_float_store
4383 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4384 /* Always assign pseudo to structure return or item passed
4385 by invisible reference. */
4386 || passed_pointer || parm == function_result_decl)
4388 /* Store the parm in a pseudoregister during the function, but we
4389 may need to do it in a wider mode. */
4391 register rtx parmreg;
4392 int regno, regnoi = 0, regnor = 0;
4394 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4396 promoted_nominal_mode
4397 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4399 parmreg = gen_reg_rtx (promoted_nominal_mode);
4400 mark_user_reg (parmreg);
4402 /* If this was an item that we received a pointer to, set DECL_RTL
4407 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)), parmreg);
4408 MEM_SET_IN_STRUCT_P (DECL_RTL (parm), aggregate);
4411 DECL_RTL (parm) = parmreg;
4413 /* Copy the value into the register. */
4414 if (nominal_mode != passed_mode
4415 || promoted_nominal_mode != promoted_mode)
4418 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4419 mode, by the caller. We now have to convert it to
4420 NOMINAL_MODE, if different. However, PARMREG may be in
4421 a different mode than NOMINAL_MODE if it is being stored
4424 If ENTRY_PARM is a hard register, it might be in a register
4425 not valid for operating in its mode (e.g., an odd-numbered
4426 register for a DFmode). In that case, moves are the only
4427 thing valid, so we can't do a convert from there. This
4428 occurs when the calling sequence allow such misaligned
4431 In addition, the conversion may involve a call, which could
4432 clobber parameters which haven't been copied to pseudo
4433 registers yet. Therefore, we must first copy the parm to
4434 a pseudo reg here, and save the conversion until after all
4435 parameters have been moved. */
4437 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4439 emit_move_insn (tempreg, validize_mem (entry_parm));
4441 push_to_sequence (conversion_insns);
4442 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4444 /* TREE_USED gets set erroneously during expand_assignment. */
4445 save_tree_used = TREE_USED (parm);
4446 expand_assignment (parm,
4447 make_tree (nominal_type, tempreg), 0, 0);
4448 TREE_USED (parm) = save_tree_used;
4449 conversion_insns = get_insns ();
4454 emit_move_insn (parmreg, validize_mem (entry_parm));
4456 /* If we were passed a pointer but the actual value
4457 can safely live in a register, put it in one. */
4458 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4459 && ! ((obey_regdecls && ! DECL_REGISTER (parm)
4460 && ! DECL_INLINE (fndecl))
4461 /* layout_decl may set this. */
4462 || TREE_ADDRESSABLE (parm)
4463 || TREE_SIDE_EFFECTS (parm)
4464 /* If -ffloat-store specified, don't put explicit
4465 float variables into registers. */
4466 || (flag_float_store
4467 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE)))
4469 /* We can't use nominal_mode, because it will have been set to
4470 Pmode above. We must use the actual mode of the parm. */
4471 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4472 mark_user_reg (parmreg);
4473 emit_move_insn (parmreg, DECL_RTL (parm));
4474 DECL_RTL (parm) = parmreg;
4475 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4479 #ifdef FUNCTION_ARG_CALLEE_COPIES
4480 /* If we are passed an arg by reference and it is our responsibility
4481 to make a copy, do it now.
4482 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4483 original argument, so we must recreate them in the call to
4484 FUNCTION_ARG_CALLEE_COPIES. */
4485 /* ??? Later add code to handle the case that if the argument isn't
4486 modified, don't do the copy. */
4488 else if (passed_pointer
4489 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4490 TYPE_MODE (DECL_ARG_TYPE (parm)),
4491 DECL_ARG_TYPE (parm),
4493 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4496 tree type = DECL_ARG_TYPE (parm);
4498 /* This sequence may involve a library call perhaps clobbering
4499 registers that haven't been copied to pseudos yet. */
4501 push_to_sequence (conversion_insns);
4503 if (TYPE_SIZE (type) == 0
4504 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4505 /* This is a variable sized object. */
4506 copy = gen_rtx_MEM (BLKmode,
4507 allocate_dynamic_stack_space
4508 (expr_size (parm), NULL_RTX,
4509 TYPE_ALIGN (type)));
4511 copy = assign_stack_temp (TYPE_MODE (type),
4512 int_size_in_bytes (type), 1);
4513 MEM_SET_IN_STRUCT_P (copy, AGGREGATE_TYPE_P (type));
4514 RTX_UNCHANGING_P (copy) = TREE_READONLY (parm);
4516 store_expr (parm, copy, 0);
4517 emit_move_insn (parmreg, XEXP (copy, 0));
4518 if (current_function_check_memory_usage)
4519 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
4520 XEXP (copy, 0), ptr_mode,
4521 GEN_INT (int_size_in_bytes (type)),
4522 TYPE_MODE (sizetype),
4523 GEN_INT (MEMORY_USE_RW),
4524 TYPE_MODE (integer_type_node));
4525 conversion_insns = get_insns ();
4529 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4531 /* In any case, record the parm's desired stack location
4532 in case we later discover it must live in the stack.
4534 If it is a COMPLEX value, store the stack location for both
4537 if (GET_CODE (parmreg) == CONCAT)
4538 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4540 regno = REGNO (parmreg);
4542 if (regno >= max_parm_reg)
4545 int old_max_parm_reg = max_parm_reg;
4547 /* It's slow to expand this one register at a time,
4548 but it's also rare and we need max_parm_reg to be
4549 precisely correct. */
4550 max_parm_reg = regno + 1;
4551 new = (rtx *) savealloc (max_parm_reg * sizeof (rtx));
4552 bcopy ((char *) parm_reg_stack_loc, (char *) new,
4553 old_max_parm_reg * sizeof (rtx));
4554 bzero ((char *) (new + old_max_parm_reg),
4555 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4556 parm_reg_stack_loc = new;
4559 if (GET_CODE (parmreg) == CONCAT)
4561 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
4563 regnor = REGNO (gen_realpart (submode, parmreg));
4564 regnoi = REGNO (gen_imagpart (submode, parmreg));
4566 if (stack_parm != 0)
4568 parm_reg_stack_loc[regnor]
4569 = gen_realpart (submode, stack_parm);
4570 parm_reg_stack_loc[regnoi]
4571 = gen_imagpart (submode, stack_parm);
4575 parm_reg_stack_loc[regnor] = 0;
4576 parm_reg_stack_loc[regnoi] = 0;
4580 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
4582 /* Mark the register as eliminable if we did no conversion
4583 and it was copied from memory at a fixed offset,
4584 and the arg pointer was not copied to a pseudo-reg.
4585 If the arg pointer is a pseudo reg or the offset formed
4586 an invalid address, such memory-equivalences
4587 as we make here would screw up life analysis for it. */
4588 if (nominal_mode == passed_mode
4591 && GET_CODE (stack_parm) == MEM
4592 && stack_offset.var == 0
4593 && reg_mentioned_p (virtual_incoming_args_rtx,
4594 XEXP (stack_parm, 0)))
4596 rtx linsn = get_last_insn ();
4599 /* Mark complex types separately. */
4600 if (GET_CODE (parmreg) == CONCAT)
4601 /* Scan backwards for the set of the real and
4603 for (sinsn = linsn; sinsn != 0;
4604 sinsn = prev_nonnote_insn (sinsn))
4606 set = single_set (sinsn);
4608 && SET_DEST (set) == regno_reg_rtx [regnoi])
4610 = gen_rtx_EXPR_LIST (REG_EQUIV,
4611 parm_reg_stack_loc[regnoi],
4614 && SET_DEST (set) == regno_reg_rtx [regnor])
4616 = gen_rtx_EXPR_LIST (REG_EQUIV,
4617 parm_reg_stack_loc[regnor],
4620 else if ((set = single_set (linsn)) != 0
4621 && SET_DEST (set) == parmreg)
4623 = gen_rtx_EXPR_LIST (REG_EQUIV,
4624 stack_parm, REG_NOTES (linsn));
4627 /* For pointer data type, suggest pointer register. */
4628 if (POINTER_TYPE_P (TREE_TYPE (parm)))
4629 mark_reg_pointer (parmreg,
4630 (TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm)))
4635 /* Value must be stored in the stack slot STACK_PARM
4636 during function execution. */
4638 if (promoted_mode != nominal_mode)
4640 /* Conversion is required. */
4641 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4643 emit_move_insn (tempreg, validize_mem (entry_parm));
4645 push_to_sequence (conversion_insns);
4646 entry_parm = convert_to_mode (nominal_mode, tempreg,
4647 TREE_UNSIGNED (TREE_TYPE (parm)));
4650 /* ??? This may need a big-endian conversion on sparc64. */
4651 stack_parm = change_address (stack_parm, nominal_mode,
4654 conversion_insns = get_insns ();
4659 if (entry_parm != stack_parm)
4661 if (stack_parm == 0)
4664 = assign_stack_local (GET_MODE (entry_parm),
4665 GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
4666 /* If this is a memory ref that contains aggregate components,
4667 mark it as such for cse and loop optimize. */
4668 MEM_SET_IN_STRUCT_P (stack_parm, aggregate);
4671 if (promoted_mode != nominal_mode)
4673 push_to_sequence (conversion_insns);
4674 emit_move_insn (validize_mem (stack_parm),
4675 validize_mem (entry_parm));
4676 conversion_insns = get_insns ();
4680 emit_move_insn (validize_mem (stack_parm),
4681 validize_mem (entry_parm));
4683 if (current_function_check_memory_usage)
4685 push_to_sequence (conversion_insns);
4686 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
4687 XEXP (stack_parm, 0), ptr_mode,
4688 GEN_INT (GET_MODE_SIZE (GET_MODE
4690 TYPE_MODE (sizetype),
4691 GEN_INT (MEMORY_USE_RW),
4692 TYPE_MODE (integer_type_node));
4694 conversion_insns = get_insns ();
4697 DECL_RTL (parm) = stack_parm;
4700 /* If this "parameter" was the place where we are receiving the
4701 function's incoming structure pointer, set up the result. */
4702 if (parm == function_result_decl)
4704 tree result = DECL_RESULT (fndecl);
4705 tree restype = TREE_TYPE (result);
4708 = gen_rtx_MEM (DECL_MODE (result), DECL_RTL (parm));
4710 MEM_SET_IN_STRUCT_P (DECL_RTL (result),
4711 AGGREGATE_TYPE_P (restype));
4714 if (TREE_THIS_VOLATILE (parm))
4715 MEM_VOLATILE_P (DECL_RTL (parm)) = 1;
4716 if (TREE_READONLY (parm))
4717 RTX_UNCHANGING_P (DECL_RTL (parm)) = 1;
4720 /* Output all parameter conversion instructions (possibly including calls)
4721 now that all parameters have been copied out of hard registers. */
4722 emit_insns (conversion_insns);
4724 last_parm_insn = get_last_insn ();
4726 current_function_args_size = stack_args_size.constant;
4728 /* Adjust function incoming argument size for alignment and
4731 #ifdef REG_PARM_STACK_SPACE
4732 #ifndef MAYBE_REG_PARM_STACK_SPACE
4733 current_function_args_size = MAX (current_function_args_size,
4734 REG_PARM_STACK_SPACE (fndecl));
4738 #ifdef PREFERRED_STACK_BOUNDARY
4739 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
4741 current_function_args_size
4742 = ((current_function_args_size + STACK_BYTES - 1)
4743 / STACK_BYTES) * STACK_BYTES;
4746 #ifdef ARGS_GROW_DOWNWARD
4747 current_function_arg_offset_rtx
4748 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
4749 : expand_expr (size_binop (MINUS_EXPR, stack_args_size.var,
4750 size_int (-stack_args_size.constant)),
4751 NULL_RTX, VOIDmode, EXPAND_MEMORY_USE_BAD));
4753 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
4756 /* See how many bytes, if any, of its args a function should try to pop
4759 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
4760 current_function_args_size);
4762 /* For stdarg.h function, save info about
4763 regs and stack space used by the named args. */
4766 current_function_args_info = args_so_far;
4768 /* Set the rtx used for the function return value. Put this in its
4769 own variable so any optimizers that need this information don't have
4770 to include tree.h. Do this here so it gets done when an inlined
4771 function gets output. */
4773 current_function_return_rtx = DECL_RTL (DECL_RESULT (fndecl));
4776 /* Indicate whether REGNO is an incoming argument to the current function
4777 that was promoted to a wider mode. If so, return the RTX for the
4778 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
4779 that REGNO is promoted from and whether the promotion was signed or
4782 #ifdef PROMOTE_FUNCTION_ARGS
4785 promoted_input_arg (regno, pmode, punsignedp)
4787 enum machine_mode *pmode;
4792 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
4793 arg = TREE_CHAIN (arg))
4794 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
4795 && REGNO (DECL_INCOMING_RTL (arg)) == regno
4796 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
4798 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
4799 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
4801 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
4802 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
4803 && mode != DECL_MODE (arg))
4805 *pmode = DECL_MODE (arg);
4806 *punsignedp = unsignedp;
4807 return DECL_INCOMING_RTL (arg);
4816 /* Compute the size and offset from the start of the stacked arguments for a
4817 parm passed in mode PASSED_MODE and with type TYPE.
4819 INITIAL_OFFSET_PTR points to the current offset into the stacked
4822 The starting offset and size for this parm are returned in *OFFSET_PTR
4823 and *ARG_SIZE_PTR, respectively.
4825 IN_REGS is non-zero if the argument will be passed in registers. It will
4826 never be set if REG_PARM_STACK_SPACE is not defined.
4828 FNDECL is the function in which the argument was defined.
4830 There are two types of rounding that are done. The first, controlled by
4831 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
4832 list to be aligned to the specific boundary (in bits). This rounding
4833 affects the initial and starting offsets, but not the argument size.
4835 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
4836 optionally rounds the size of the parm to PARM_BOUNDARY. The
4837 initial offset is not affected by this rounding, while the size always
4838 is and the starting offset may be. */
4840 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
4841 initial_offset_ptr is positive because locate_and_pad_parm's
4842 callers pass in the total size of args so far as
4843 initial_offset_ptr. arg_size_ptr is always positive.*/
4846 locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
4847 initial_offset_ptr, offset_ptr, arg_size_ptr)
4848 enum machine_mode passed_mode;
4852 struct args_size *initial_offset_ptr;
4853 struct args_size *offset_ptr;
4854 struct args_size *arg_size_ptr;
4857 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
4858 enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
4859 int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
4861 #ifdef REG_PARM_STACK_SPACE
4862 /* If we have found a stack parm before we reach the end of the
4863 area reserved for registers, skip that area. */
4866 int reg_parm_stack_space = 0;
4868 #ifdef MAYBE_REG_PARM_STACK_SPACE
4869 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
4871 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
4873 if (reg_parm_stack_space > 0)
4875 if (initial_offset_ptr->var)
4877 initial_offset_ptr->var
4878 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
4879 size_int (reg_parm_stack_space));
4880 initial_offset_ptr->constant = 0;
4882 else if (initial_offset_ptr->constant < reg_parm_stack_space)
4883 initial_offset_ptr->constant = reg_parm_stack_space;
4886 #endif /* REG_PARM_STACK_SPACE */
4888 arg_size_ptr->var = 0;
4889 arg_size_ptr->constant = 0;
4891 #ifdef ARGS_GROW_DOWNWARD
4892 if (initial_offset_ptr->var)
4894 offset_ptr->constant = 0;
4895 offset_ptr->var = size_binop (MINUS_EXPR, integer_zero_node,
4896 initial_offset_ptr->var);
4900 offset_ptr->constant = - initial_offset_ptr->constant;
4901 offset_ptr->var = 0;
4903 if (where_pad != none
4904 && (TREE_CODE (sizetree) != INTEGER_CST
4905 || ((TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)))
4906 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
4907 SUB_PARM_SIZE (*offset_ptr, sizetree);
4908 if (where_pad != downward)
4909 pad_to_arg_alignment (offset_ptr, boundary);
4910 if (initial_offset_ptr->var)
4912 arg_size_ptr->var = size_binop (MINUS_EXPR,
4913 size_binop (MINUS_EXPR,
4915 initial_offset_ptr->var),
4920 arg_size_ptr->constant = (- initial_offset_ptr->constant
4921 - offset_ptr->constant);
4923 #else /* !ARGS_GROW_DOWNWARD */
4924 pad_to_arg_alignment (initial_offset_ptr, boundary);
4925 *offset_ptr = *initial_offset_ptr;
4927 #ifdef PUSH_ROUNDING
4928 if (passed_mode != BLKmode)
4929 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
4932 /* Pad_below needs the pre-rounded size to know how much to pad below
4933 so this must be done before rounding up. */
4934 if (where_pad == downward
4935 /* However, BLKmode args passed in regs have their padding done elsewhere.
4936 The stack slot must be able to hold the entire register. */
4937 && !(in_regs && passed_mode == BLKmode))
4938 pad_below (offset_ptr, passed_mode, sizetree);
4940 if (where_pad != none
4941 && (TREE_CODE (sizetree) != INTEGER_CST
4942 || ((TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)))
4943 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
4945 ADD_PARM_SIZE (*arg_size_ptr, sizetree);
4946 #endif /* ARGS_GROW_DOWNWARD */
4949 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
4950 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
4953 pad_to_arg_alignment (offset_ptr, boundary)
4954 struct args_size *offset_ptr;
4957 int boundary_in_bytes = boundary / BITS_PER_UNIT;
4959 if (boundary > BITS_PER_UNIT)
4961 if (offset_ptr->var)
4964 #ifdef ARGS_GROW_DOWNWARD
4969 (ARGS_SIZE_TREE (*offset_ptr),
4970 boundary / BITS_PER_UNIT);
4971 offset_ptr->constant = 0; /*?*/
4974 offset_ptr->constant =
4975 #ifdef ARGS_GROW_DOWNWARD
4976 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
4978 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
4983 #ifndef ARGS_GROW_DOWNWARD
4985 pad_below (offset_ptr, passed_mode, sizetree)
4986 struct args_size *offset_ptr;
4987 enum machine_mode passed_mode;
4990 if (passed_mode != BLKmode)
4992 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
4993 offset_ptr->constant
4994 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
4995 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
4996 - GET_MODE_SIZE (passed_mode));
5000 if (TREE_CODE (sizetree) != INTEGER_CST
5001 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5003 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5004 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5006 ADD_PARM_SIZE (*offset_ptr, s2);
5007 SUB_PARM_SIZE (*offset_ptr, sizetree);
5013 #ifdef ARGS_GROW_DOWNWARD
5015 round_down (value, divisor)
5019 return size_binop (MULT_EXPR,
5020 size_binop (FLOOR_DIV_EXPR, value, size_int (divisor)),
5021 size_int (divisor));
5025 /* Walk the tree of blocks describing the binding levels within a function
5026 and warn about uninitialized variables.
5027 This is done after calling flow_analysis and before global_alloc
5028 clobbers the pseudo-regs to hard regs. */
5031 uninitialized_vars_warning (block)
5034 register tree decl, sub;
5035 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5037 if (TREE_CODE (decl) == VAR_DECL
5038 /* These warnings are unreliable for and aggregates
5039 because assigning the fields one by one can fail to convince
5040 flow.c that the entire aggregate was initialized.
5041 Unions are troublesome because members may be shorter. */
5042 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5043 && DECL_RTL (decl) != 0
5044 && GET_CODE (DECL_RTL (decl)) == REG
5045 /* Global optimizations can make it difficult to determine if a
5046 particular variable has been initialized. However, a VAR_DECL
5047 with a nonzero DECL_INITIAL had an initializer, so do not
5048 claim it is potentially uninitialized.
5050 We do not care about the actual value in DECL_INITIAL, so we do
5051 not worry that it may be a dangling pointer. */
5052 && DECL_INITIAL (decl) == NULL_TREE
5053 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5054 warning_with_decl (decl,
5055 "`%s' might be used uninitialized in this function");
5056 if (TREE_CODE (decl) == VAR_DECL
5057 && DECL_RTL (decl) != 0
5058 && GET_CODE (DECL_RTL (decl)) == REG
5059 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5060 warning_with_decl (decl,
5061 "variable `%s' might be clobbered by `longjmp' or `vfork'");
5063 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5064 uninitialized_vars_warning (sub);
5067 /* Do the appropriate part of uninitialized_vars_warning
5068 but for arguments instead of local variables. */
5071 setjmp_args_warning ()
5074 for (decl = DECL_ARGUMENTS (current_function_decl);
5075 decl; decl = TREE_CHAIN (decl))
5076 if (DECL_RTL (decl) != 0
5077 && GET_CODE (DECL_RTL (decl)) == REG
5078 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5079 warning_with_decl (decl, "argument `%s' might be clobbered by `longjmp' or `vfork'");
5082 /* If this function call setjmp, put all vars into the stack
5083 unless they were declared `register'. */
5086 setjmp_protect (block)
5089 register tree decl, sub;
5090 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5091 if ((TREE_CODE (decl) == VAR_DECL
5092 || TREE_CODE (decl) == PARM_DECL)
5093 && DECL_RTL (decl) != 0
5094 && (GET_CODE (DECL_RTL (decl)) == REG
5095 || (GET_CODE (DECL_RTL (decl)) == MEM
5096 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5097 /* If this variable came from an inline function, it must be
5098 that its life doesn't overlap the setjmp. If there was a
5099 setjmp in the function, it would already be in memory. We
5100 must exclude such variable because their DECL_RTL might be
5101 set to strange things such as virtual_stack_vars_rtx. */
5102 && ! DECL_FROM_INLINE (decl)
5104 #ifdef NON_SAVING_SETJMP
5105 /* If longjmp doesn't restore the registers,
5106 don't put anything in them. */
5110 ! DECL_REGISTER (decl)))
5111 put_var_into_stack (decl);
5112 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5113 setjmp_protect (sub);
5116 /* Like the previous function, but for args instead of local variables. */
5119 setjmp_protect_args ()
5122 for (decl = DECL_ARGUMENTS (current_function_decl);
5123 decl; decl = TREE_CHAIN (decl))
5124 if ((TREE_CODE (decl) == VAR_DECL
5125 || TREE_CODE (decl) == PARM_DECL)
5126 && DECL_RTL (decl) != 0
5127 && (GET_CODE (DECL_RTL (decl)) == REG
5128 || (GET_CODE (DECL_RTL (decl)) == MEM
5129 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5131 /* If longjmp doesn't restore the registers,
5132 don't put anything in them. */
5133 #ifdef NON_SAVING_SETJMP
5137 ! DECL_REGISTER (decl)))
5138 put_var_into_stack (decl);
5141 /* Return the context-pointer register corresponding to DECL,
5142 or 0 if it does not need one. */
5145 lookup_static_chain (decl)
5148 tree context = decl_function_context (decl);
5152 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5155 /* We treat inline_function_decl as an alias for the current function
5156 because that is the inline function whose vars, types, etc.
5157 are being merged into the current function.
5158 See expand_inline_function. */
5159 if (context == current_function_decl || context == inline_function_decl)
5160 return virtual_stack_vars_rtx;
5162 for (link = context_display; link; link = TREE_CHAIN (link))
5163 if (TREE_PURPOSE (link) == context)
5164 return RTL_EXPR_RTL (TREE_VALUE (link));
5169 /* Convert a stack slot address ADDR for variable VAR
5170 (from a containing function)
5171 into an address valid in this function (using a static chain). */
5174 fix_lexical_addr (addr, var)
5179 HOST_WIDE_INT displacement;
5180 tree context = decl_function_context (var);
5181 struct function *fp;
5184 /* If this is the present function, we need not do anything. */
5185 if (context == current_function_decl || context == inline_function_decl)
5188 for (fp = outer_function_chain; fp; fp = fp->next)
5189 if (fp->decl == context)
5195 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5196 addr = XEXP (XEXP (addr, 0), 0);
5198 /* Decode given address as base reg plus displacement. */
5199 if (GET_CODE (addr) == REG)
5200 basereg = addr, displacement = 0;
5201 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5202 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5206 /* We accept vars reached via the containing function's
5207 incoming arg pointer and via its stack variables pointer. */
5208 if (basereg == fp->internal_arg_pointer)
5210 /* If reached via arg pointer, get the arg pointer value
5211 out of that function's stack frame.
5213 There are two cases: If a separate ap is needed, allocate a
5214 slot in the outer function for it and dereference it that way.
5215 This is correct even if the real ap is actually a pseudo.
5216 Otherwise, just adjust the offset from the frame pointer to
5219 #ifdef NEED_SEPARATE_AP
5222 if (fp->arg_pointer_save_area == 0)
5223 fp->arg_pointer_save_area
5224 = assign_outer_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0, fp);
5226 addr = fix_lexical_addr (XEXP (fp->arg_pointer_save_area, 0), var);
5227 addr = memory_address (Pmode, addr);
5229 base = copy_to_reg (gen_rtx_MEM (Pmode, addr));
5231 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5232 base = lookup_static_chain (var);
5236 else if (basereg == virtual_stack_vars_rtx)
5238 /* This is the same code as lookup_static_chain, duplicated here to
5239 avoid an extra call to decl_function_context. */
5242 for (link = context_display; link; link = TREE_CHAIN (link))
5243 if (TREE_PURPOSE (link) == context)
5245 base = RTL_EXPR_RTL (TREE_VALUE (link));
5253 /* Use same offset, relative to appropriate static chain or argument
5255 return plus_constant (base, displacement);
5258 /* Return the address of the trampoline for entering nested fn FUNCTION.
5259 If necessary, allocate a trampoline (in the stack frame)
5260 and emit rtl to initialize its contents (at entry to this function). */
5263 trampoline_address (function)
5269 struct function *fp;
5272 /* Find an existing trampoline and return it. */
5273 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5274 if (TREE_PURPOSE (link) == function)
5276 round_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5278 for (fp = outer_function_chain; fp; fp = fp->next)
5279 for (link = fp->trampoline_list; link; link = TREE_CHAIN (link))
5280 if (TREE_PURPOSE (link) == function)
5282 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5284 return round_trampoline_addr (tramp);
5287 /* None exists; we must make one. */
5289 /* Find the `struct function' for the function containing FUNCTION. */
5291 fn_context = decl_function_context (function);
5292 if (fn_context != current_function_decl
5293 && fn_context != inline_function_decl)
5294 for (fp = outer_function_chain; fp; fp = fp->next)
5295 if (fp->decl == fn_context)
5298 /* Allocate run-time space for this trampoline
5299 (usually in the defining function's stack frame). */
5300 #ifdef ALLOCATE_TRAMPOLINE
5301 tramp = ALLOCATE_TRAMPOLINE (fp);
5303 /* If rounding needed, allocate extra space
5304 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5305 #ifdef TRAMPOLINE_ALIGNMENT
5306 #define TRAMPOLINE_REAL_SIZE \
5307 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5309 #define TRAMPOLINE_REAL_SIZE (TRAMPOLINE_SIZE)
5312 tramp = assign_outer_stack_local (BLKmode, TRAMPOLINE_REAL_SIZE, 0, fp);
5314 tramp = assign_stack_local (BLKmode, TRAMPOLINE_REAL_SIZE, 0);
5317 /* Record the trampoline for reuse and note it for later initialization
5318 by expand_function_end. */
5321 push_obstacks (fp->function_maybepermanent_obstack,
5322 fp->function_maybepermanent_obstack);
5323 rtlexp = make_node (RTL_EXPR);
5324 RTL_EXPR_RTL (rtlexp) = tramp;
5325 fp->trampoline_list = tree_cons (function, rtlexp, fp->trampoline_list);
5330 /* Make the RTL_EXPR node temporary, not momentary, so that the
5331 trampoline_list doesn't become garbage. */
5332 int momentary = suspend_momentary ();
5333 rtlexp = make_node (RTL_EXPR);
5334 resume_momentary (momentary);
5336 RTL_EXPR_RTL (rtlexp) = tramp;
5337 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5340 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5341 return round_trampoline_addr (tramp);
5344 /* Given a trampoline address,
5345 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5348 round_trampoline_addr (tramp)
5351 #ifdef TRAMPOLINE_ALIGNMENT
5352 /* Round address up to desired boundary. */
5353 rtx temp = gen_reg_rtx (Pmode);
5354 temp = expand_binop (Pmode, add_optab, tramp,
5355 GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1),
5356 temp, 0, OPTAB_LIB_WIDEN);
5357 tramp = expand_binop (Pmode, and_optab, temp,
5358 GEN_INT (- TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT),
5359 temp, 0, OPTAB_LIB_WIDEN);
5364 /* The functions identify_blocks and reorder_blocks provide a way to
5365 reorder the tree of BLOCK nodes, for optimizers that reshuffle or
5366 duplicate portions of the RTL code. Call identify_blocks before
5367 changing the RTL, and call reorder_blocks after. */
5369 /* Put all this function's BLOCK nodes including those that are chained
5370 onto the first block into a vector, and return it.
5371 Also store in each NOTE for the beginning or end of a block
5372 the index of that block in the vector.
5373 The arguments are BLOCK, the chain of top-level blocks of the function,
5374 and INSNS, the insn chain of the function. */
5377 identify_blocks (block, insns)
5385 int next_block_number = 1;
5386 int current_block_number = 1;
5392 n_blocks = all_blocks (block, 0);
5393 block_vector = (tree *) xmalloc (n_blocks * sizeof (tree));
5394 block_stack = (int *) alloca (n_blocks * sizeof (int));
5396 all_blocks (block, block_vector);
5398 for (insn = insns; insn; insn = NEXT_INSN (insn))
5399 if (GET_CODE (insn) == NOTE)
5401 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5403 block_stack[depth++] = current_block_number;
5404 current_block_number = next_block_number;
5405 NOTE_BLOCK_NUMBER (insn) = next_block_number++;
5407 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5409 NOTE_BLOCK_NUMBER (insn) = current_block_number;
5410 current_block_number = block_stack[--depth];
5414 if (n_blocks != next_block_number)
5417 return block_vector;
5420 /* Given BLOCK_VECTOR which was returned by identify_blocks,
5421 and a revised instruction chain, rebuild the tree structure
5422 of BLOCK nodes to correspond to the new order of RTL.
5423 The new block tree is inserted below TOP_BLOCK.
5424 Returns the current top-level block. */
5427 reorder_blocks (block_vector, block, insns)
5432 tree current_block = block;
5435 if (block_vector == 0)
5438 /* Prune the old trees away, so that it doesn't get in the way. */
5439 BLOCK_SUBBLOCKS (current_block) = 0;
5440 BLOCK_CHAIN (current_block) = 0;
5442 for (insn = insns; insn; insn = NEXT_INSN (insn))
5443 if (GET_CODE (insn) == NOTE)
5445 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5447 tree block = block_vector[NOTE_BLOCK_NUMBER (insn)];
5448 /* If we have seen this block before, copy it. */
5449 if (TREE_ASM_WRITTEN (block))
5450 block = copy_node (block);
5451 BLOCK_SUBBLOCKS (block) = 0;
5452 TREE_ASM_WRITTEN (block) = 1;
5453 BLOCK_SUPERCONTEXT (block) = current_block;
5454 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
5455 BLOCK_SUBBLOCKS (current_block) = block;
5456 current_block = block;
5457 NOTE_SOURCE_FILE (insn) = 0;
5459 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5461 BLOCK_SUBBLOCKS (current_block)
5462 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5463 current_block = BLOCK_SUPERCONTEXT (current_block);
5464 NOTE_SOURCE_FILE (insn) = 0;
5468 BLOCK_SUBBLOCKS (current_block)
5469 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5470 return current_block;
5473 /* Reverse the order of elements in the chain T of blocks,
5474 and return the new head of the chain (old last element). */
5480 register tree prev = 0, decl, next;
5481 for (decl = t; decl; decl = next)
5483 next = BLOCK_CHAIN (decl);
5484 BLOCK_CHAIN (decl) = prev;
5490 /* Count the subblocks of the list starting with BLOCK, and list them
5491 all into the vector VECTOR. Also clear TREE_ASM_WRITTEN in all
5495 all_blocks (block, vector)
5503 TREE_ASM_WRITTEN (block) = 0;
5505 /* Record this block. */
5507 vector[n_blocks] = block;
5511 /* Record the subblocks, and their subblocks... */
5512 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
5513 vector ? vector + n_blocks : 0);
5514 block = BLOCK_CHAIN (block);
5520 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
5521 and initialize static variables for generating RTL for the statements
5525 init_function_start (subr, filename, line)
5530 init_stmt_for_function ();
5532 cse_not_expected = ! optimize;
5534 /* Caller save not needed yet. */
5535 caller_save_needed = 0;
5537 /* No stack slots have been made yet. */
5538 stack_slot_list = 0;
5540 /* There is no stack slot for handling nonlocal gotos. */
5541 nonlocal_goto_handler_slots = 0;
5542 nonlocal_goto_stack_level = 0;
5544 /* No labels have been declared for nonlocal use. */
5545 nonlocal_labels = 0;
5547 /* No function calls so far in this function. */
5548 function_call_count = 0;
5550 /* No parm regs have been allocated.
5551 (This is important for output_inline_function.) */
5552 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
5554 /* Initialize the RTL mechanism. */
5557 /* Initialize the queue of pending postincrement and postdecrements,
5558 and some other info in expr.c. */
5561 /* We haven't done register allocation yet. */
5564 init_const_rtx_hash_table ();
5566 current_function_name = (*decl_printable_name) (subr, 2);
5568 /* Nonzero if this is a nested function that uses a static chain. */
5570 current_function_needs_context
5571 = (decl_function_context (current_function_decl) != 0
5572 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
5574 /* Set if a call to setjmp is seen. */
5575 current_function_calls_setjmp = 0;
5577 /* Set if a call to longjmp is seen. */
5578 current_function_calls_longjmp = 0;
5580 current_function_calls_alloca = 0;
5581 current_function_has_nonlocal_label = 0;
5582 current_function_has_nonlocal_goto = 0;
5583 current_function_contains_functions = 0;
5584 current_function_sp_is_unchanging = 0;
5585 current_function_addresses_labels = 0;
5586 current_function_is_thunk = 0;
5588 current_function_returns_pcc_struct = 0;
5589 current_function_returns_struct = 0;
5590 current_function_epilogue_delay_list = 0;
5591 current_function_uses_const_pool = 0;
5592 current_function_uses_pic_offset_table = 0;
5593 current_function_cannot_inline = 0;
5595 /* We have not yet needed to make a label to jump to for tail-recursion. */
5596 tail_recursion_label = 0;
5598 /* We haven't had a need to make a save area for ap yet. */
5600 arg_pointer_save_area = 0;
5602 /* No stack slots allocated yet. */
5605 /* No SAVE_EXPRs in this function yet. */
5608 /* No RTL_EXPRs in this function yet. */
5611 /* Set up to allocate temporaries. */
5614 /* Within function body, compute a type's size as soon it is laid out. */
5615 immediate_size_expand++;
5617 /* We haven't made any trampolines for this function yet. */
5618 trampoline_list = 0;
5620 init_pending_stack_adjust ();
5621 inhibit_defer_pop = 0;
5623 current_function_outgoing_args_size = 0;
5625 /* Prevent ever trying to delete the first instruction of a function.
5626 Also tell final how to output a linenum before the function prologue.
5627 Note linenums could be missing, e.g. when compiling a Java .class file. */
5629 emit_line_note (filename, line);
5631 /* Make sure first insn is a note even if we don't want linenums.
5632 This makes sure the first insn will never be deleted.
5633 Also, final expects a note to appear there. */
5634 emit_note (NULL_PTR, NOTE_INSN_DELETED);
5636 /* Set flags used by final.c. */
5637 if (aggregate_value_p (DECL_RESULT (subr)))
5639 #ifdef PCC_STATIC_STRUCT_RETURN
5640 current_function_returns_pcc_struct = 1;
5642 current_function_returns_struct = 1;
5645 /* Warn if this value is an aggregate type,
5646 regardless of which calling convention we are using for it. */
5647 if (warn_aggregate_return
5648 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
5649 warning ("function returns an aggregate");
5651 current_function_returns_pointer
5652 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
5654 /* Indicate that we need to distinguish between the return value of the
5655 present function and the return value of a function being called. */
5656 rtx_equal_function_value_matters = 1;
5658 /* Indicate that we have not instantiated virtual registers yet. */
5659 virtuals_instantiated = 0;
5661 /* Indicate we have no need of a frame pointer yet. */
5662 frame_pointer_needed = 0;
5664 /* By default assume not varargs or stdarg. */
5665 current_function_varargs = 0;
5666 current_function_stdarg = 0;
5669 /* Indicate that the current function uses extra args
5670 not explicitly mentioned in the argument list in any fashion. */
5675 current_function_varargs = 1;
5678 /* Expand a call to __main at the beginning of a possible main function. */
5680 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
5681 #undef HAS_INIT_SECTION
5682 #define HAS_INIT_SECTION
5686 expand_main_function ()
5688 #if !defined (HAS_INIT_SECTION)
5689 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, NAME__MAIN), 0,
5691 #endif /* not HAS_INIT_SECTION */
5694 extern struct obstack permanent_obstack;
5696 /* Start the RTL for a new function, and set variables used for
5698 SUBR is the FUNCTION_DECL node.
5699 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
5700 the function's parameters, which must be run at any return statement. */
5703 expand_function_start (subr, parms_have_cleanups)
5705 int parms_have_cleanups;
5709 rtx last_ptr = NULL_RTX;
5711 /* Make sure volatile mem refs aren't considered
5712 valid operands of arithmetic insns. */
5713 init_recog_no_volatile ();
5715 /* Set this before generating any memory accesses. */
5716 current_function_check_memory_usage
5717 = (flag_check_memory_usage
5718 && ! DECL_NO_CHECK_MEMORY_USAGE (current_function_decl));
5720 current_function_instrument_entry_exit
5721 = (flag_instrument_function_entry_exit
5722 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
5724 /* If function gets a static chain arg, store it in the stack frame.
5725 Do this first, so it gets the first stack slot offset. */
5726 if (current_function_needs_context)
5728 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
5730 /* Delay copying static chain if it is not a register to avoid
5731 conflicts with regs used for parameters. */
5732 if (! SMALL_REGISTER_CLASSES
5733 || GET_CODE (static_chain_incoming_rtx) == REG)
5734 emit_move_insn (last_ptr, static_chain_incoming_rtx);
5737 /* If the parameters of this function need cleaning up, get a label
5738 for the beginning of the code which executes those cleanups. This must
5739 be done before doing anything with return_label. */
5740 if (parms_have_cleanups)
5741 cleanup_label = gen_label_rtx ();
5745 /* Make the label for return statements to jump to, if this machine
5746 does not have a one-instruction return and uses an epilogue,
5747 or if it returns a structure, or if it has parm cleanups. */
5749 if (cleanup_label == 0 && HAVE_return
5750 && ! current_function_instrument_entry_exit
5751 && ! current_function_returns_pcc_struct
5752 && ! (current_function_returns_struct && ! optimize))
5755 return_label = gen_label_rtx ();
5757 return_label = gen_label_rtx ();
5760 /* Initialize rtx used to return the value. */
5761 /* Do this before assign_parms so that we copy the struct value address
5762 before any library calls that assign parms might generate. */
5764 /* Decide whether to return the value in memory or in a register. */
5765 if (aggregate_value_p (DECL_RESULT (subr)))
5767 /* Returning something that won't go in a register. */
5768 register rtx value_address = 0;
5770 #ifdef PCC_STATIC_STRUCT_RETURN
5771 if (current_function_returns_pcc_struct)
5773 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
5774 value_address = assemble_static_space (size);
5779 /* Expect to be passed the address of a place to store the value.
5780 If it is passed as an argument, assign_parms will take care of
5782 if (struct_value_incoming_rtx)
5784 value_address = gen_reg_rtx (Pmode);
5785 emit_move_insn (value_address, struct_value_incoming_rtx);
5790 DECL_RTL (DECL_RESULT (subr))
5791 = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
5792 MEM_SET_IN_STRUCT_P (DECL_RTL (DECL_RESULT (subr)),
5793 AGGREGATE_TYPE_P (TREE_TYPE
5798 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
5799 /* If return mode is void, this decl rtl should not be used. */
5800 DECL_RTL (DECL_RESULT (subr)) = 0;
5801 else if (parms_have_cleanups || current_function_instrument_entry_exit)
5803 /* If function will end with cleanup code for parms,
5804 compute the return values into a pseudo reg,
5805 which we will copy into the true return register
5806 after the cleanups are done. */
5808 enum machine_mode mode = DECL_MODE (DECL_RESULT (subr));
5810 #ifdef PROMOTE_FUNCTION_RETURN
5811 tree type = TREE_TYPE (DECL_RESULT (subr));
5812 int unsignedp = TREE_UNSIGNED (type);
5814 mode = promote_mode (type, mode, &unsignedp, 1);
5817 DECL_RTL (DECL_RESULT (subr)) = gen_reg_rtx (mode);
5820 /* Scalar, returned in a register. */
5822 #ifdef FUNCTION_OUTGOING_VALUE
5823 DECL_RTL (DECL_RESULT (subr))
5824 = FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (subr)), subr);
5826 DECL_RTL (DECL_RESULT (subr))
5827 = FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (subr)), subr);
5830 /* Mark this reg as the function's return value. */
5831 if (GET_CODE (DECL_RTL (DECL_RESULT (subr))) == REG)
5833 REG_FUNCTION_VALUE_P (DECL_RTL (DECL_RESULT (subr))) = 1;
5834 /* Needed because we may need to move this to memory
5835 in case it's a named return value whose address is taken. */
5836 DECL_REGISTER (DECL_RESULT (subr)) = 1;
5840 /* Initialize rtx for parameters and local variables.
5841 In some cases this requires emitting insns. */
5843 assign_parms (subr, 0);
5845 /* Copy the static chain now if it wasn't a register. The delay is to
5846 avoid conflicts with the parameter passing registers. */
5848 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
5849 if (GET_CODE (static_chain_incoming_rtx) != REG)
5850 emit_move_insn (last_ptr, static_chain_incoming_rtx);
5852 /* The following was moved from init_function_start.
5853 The move is supposed to make sdb output more accurate. */
5854 /* Indicate the beginning of the function body,
5855 as opposed to parm setup. */
5856 emit_note (NULL_PTR, NOTE_INSN_FUNCTION_BEG);
5858 /* If doing stupid allocation, mark parms as born here. */
5860 if (GET_CODE (get_last_insn ()) != NOTE)
5861 emit_note (NULL_PTR, NOTE_INSN_DELETED);
5862 parm_birth_insn = get_last_insn ();
5866 for (i = LAST_VIRTUAL_REGISTER + 1; i < max_parm_reg; i++)
5867 use_variable (regno_reg_rtx[i]);
5869 if (current_function_internal_arg_pointer != virtual_incoming_args_rtx)
5870 use_variable (current_function_internal_arg_pointer);
5873 context_display = 0;
5874 if (current_function_needs_context)
5876 /* Fetch static chain values for containing functions. */
5877 tem = decl_function_context (current_function_decl);
5878 /* If not doing stupid register allocation copy the static chain
5879 pointer into a pseudo. If we have small register classes, copy
5880 the value from memory if static_chain_incoming_rtx is a REG. If
5881 we do stupid register allocation, we use the stack address
5883 if (tem && ! obey_regdecls)
5885 /* If the static chain originally came in a register, put it back
5886 there, then move it out in the next insn. The reason for
5887 this peculiar code is to satisfy function integration. */
5888 if (SMALL_REGISTER_CLASSES
5889 && GET_CODE (static_chain_incoming_rtx) == REG)
5890 emit_move_insn (static_chain_incoming_rtx, last_ptr);
5891 last_ptr = copy_to_reg (static_chain_incoming_rtx);
5896 tree rtlexp = make_node (RTL_EXPR);
5898 RTL_EXPR_RTL (rtlexp) = last_ptr;
5899 context_display = tree_cons (tem, rtlexp, context_display);
5900 tem = decl_function_context (tem);
5903 /* Chain thru stack frames, assuming pointer to next lexical frame
5904 is found at the place we always store it. */
5905 #ifdef FRAME_GROWS_DOWNWARD
5906 last_ptr = plus_constant (last_ptr, - GET_MODE_SIZE (Pmode));
5908 last_ptr = copy_to_reg (gen_rtx_MEM (Pmode,
5909 memory_address (Pmode, last_ptr)));
5911 /* If we are not optimizing, ensure that we know that this
5912 piece of context is live over the entire function. */
5914 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
5919 if (current_function_instrument_entry_exit)
5921 rtx fun = DECL_RTL (current_function_decl);
5922 if (GET_CODE (fun) == MEM)
5923 fun = XEXP (fun, 0);
5926 emit_library_call (profile_function_entry_libfunc, 0, VOIDmode, 2,
5928 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
5930 hard_frame_pointer_rtx),
5934 /* After the display initializations is where the tail-recursion label
5935 should go, if we end up needing one. Ensure we have a NOTE here
5936 since some things (like trampolines) get placed before this. */
5937 tail_recursion_reentry = emit_note (NULL_PTR, NOTE_INSN_DELETED);
5939 /* Evaluate now the sizes of any types declared among the arguments. */
5940 for (tem = nreverse (get_pending_sizes ()); tem; tem = TREE_CHAIN (tem))
5942 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode,
5943 EXPAND_MEMORY_USE_BAD);
5944 /* Flush the queue in case this parameter declaration has
5949 /* Make sure there is a line number after the function entry setup code. */
5950 force_next_line_note ();
5953 /* Generate RTL for the end of the current function.
5954 FILENAME and LINE are the current position in the source file.
5956 It is up to language-specific callers to do cleanups for parameters--
5957 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
5960 expand_function_end (filename, line, end_bindings)
5968 #ifdef TRAMPOLINE_TEMPLATE
5969 static rtx initial_trampoline;
5972 #ifdef NON_SAVING_SETJMP
5973 /* Don't put any variables in registers if we call setjmp
5974 on a machine that fails to restore the registers. */
5975 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
5977 if (DECL_INITIAL (current_function_decl) != error_mark_node)
5978 setjmp_protect (DECL_INITIAL (current_function_decl));
5980 setjmp_protect_args ();
5984 /* Save the argument pointer if a save area was made for it. */
5985 if (arg_pointer_save_area)
5987 /* arg_pointer_save_area may not be a valid memory address, so we
5988 have to check it and fix it if necessary. */
5991 emit_move_insn (validize_mem (arg_pointer_save_area),
5992 virtual_incoming_args_rtx);
5993 seq = gen_sequence ();
5995 emit_insn_before (seq, tail_recursion_reentry);
5998 /* Initialize any trampolines required by this function. */
5999 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6001 tree function = TREE_PURPOSE (link);
6002 rtx context = lookup_static_chain (function);
6003 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6004 #ifdef TRAMPOLINE_TEMPLATE
6009 #ifdef TRAMPOLINE_TEMPLATE
6010 /* First make sure this compilation has a template for
6011 initializing trampolines. */
6012 if (initial_trampoline == 0)
6014 end_temporary_allocation ();
6016 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6017 resume_temporary_allocation ();
6021 /* Generate insns to initialize the trampoline. */
6023 tramp = round_trampoline_addr (XEXP (tramp, 0));
6024 #ifdef TRAMPOLINE_TEMPLATE
6025 blktramp = change_address (initial_trampoline, BLKmode, tramp);
6026 emit_block_move (blktramp, initial_trampoline,
6027 GEN_INT (TRAMPOLINE_SIZE),
6028 TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
6030 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6034 /* Put those insns at entry to the containing function (this one). */
6035 emit_insns_before (seq, tail_recursion_reentry);
6038 /* If we are doing stack checking and this function makes calls,
6039 do a stack probe at the start of the function to ensure we have enough
6040 space for another stack frame. */
6041 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6045 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6046 if (GET_CODE (insn) == CALL_INSN)
6049 probe_stack_range (STACK_CHECK_PROTECT,
6050 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6053 emit_insns_before (seq, tail_recursion_reentry);
6058 /* Warn about unused parms if extra warnings were specified. */
6059 if (warn_unused && extra_warnings)
6063 for (decl = DECL_ARGUMENTS (current_function_decl);
6064 decl; decl = TREE_CHAIN (decl))
6065 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6066 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6067 warning_with_decl (decl, "unused parameter `%s'");
6070 /* Delete handlers for nonlocal gotos if nothing uses them. */
6071 if (nonlocal_goto_handler_slots != 0
6072 && ! current_function_has_nonlocal_label)
6075 /* End any sequences that failed to be closed due to syntax errors. */
6076 while (in_sequence_p ())
6079 /* Outside function body, can't compute type's actual size
6080 until next function's body starts. */
6081 immediate_size_expand--;
6083 /* If doing stupid register allocation,
6084 mark register parms as dying here. */
6089 for (i = LAST_VIRTUAL_REGISTER + 1; i < max_parm_reg; i++)
6090 use_variable (regno_reg_rtx[i]);
6092 /* Likewise for the regs of all the SAVE_EXPRs in the function. */
6094 for (tem = save_expr_regs; tem; tem = XEXP (tem, 1))
6096 use_variable (XEXP (tem, 0));
6097 use_variable_after (XEXP (tem, 0), parm_birth_insn);
6100 if (current_function_internal_arg_pointer != virtual_incoming_args_rtx)
6101 use_variable (current_function_internal_arg_pointer);
6104 clear_pending_stack_adjust ();
6105 do_pending_stack_adjust ();
6107 /* Mark the end of the function body.
6108 If control reaches this insn, the function can drop through
6109 without returning a value. */
6110 emit_note (NULL_PTR, NOTE_INSN_FUNCTION_END);
6112 /* Must mark the last line number note in the function, so that the test
6113 coverage code can avoid counting the last line twice. This just tells
6114 the code to ignore the immediately following line note, since there
6115 already exists a copy of this note somewhere above. This line number
6116 note is still needed for debugging though, so we can't delete it. */
6117 if (flag_test_coverage)
6118 emit_note (NULL_PTR, NOTE_REPEATED_LINE_NUMBER);
6120 /* Output a linenumber for the end of the function.
6121 SDB depends on this. */
6122 emit_line_note_force (filename, line);
6124 /* Output the label for the actual return from the function,
6125 if one is expected. This happens either because a function epilogue
6126 is used instead of a return instruction, or because a return was done
6127 with a goto in order to run local cleanups, or because of pcc-style
6128 structure returning. */
6131 emit_label (return_label);
6133 /* C++ uses this. */
6135 expand_end_bindings (0, 0, 0);
6137 /* Now handle any leftover exception regions that may have been
6138 created for the parameters. */
6140 rtx last = get_last_insn ();
6143 expand_leftover_cleanups ();
6145 /* If the above emitted any code, may sure we jump around it. */
6146 if (last != get_last_insn ())
6148 label = gen_label_rtx ();
6149 last = emit_jump_insn_after (gen_jump (label), last);
6150 last = emit_barrier_after (last);
6155 if (current_function_instrument_entry_exit)
6157 rtx fun = DECL_RTL (current_function_decl);
6158 if (GET_CODE (fun) == MEM)
6159 fun = XEXP (fun, 0);
6162 emit_library_call (profile_function_exit_libfunc, 0, VOIDmode, 2,
6164 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6166 hard_frame_pointer_rtx),
6170 /* If we had calls to alloca, and this machine needs
6171 an accurate stack pointer to exit the function,
6172 insert some code to save and restore the stack pointer. */
6173 #ifdef EXIT_IGNORE_STACK
6174 if (! EXIT_IGNORE_STACK)
6176 if (current_function_calls_alloca)
6180 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
6181 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
6184 /* If scalar return value was computed in a pseudo-reg,
6185 copy that to the hard return register. */
6186 if (DECL_RTL (DECL_RESULT (current_function_decl)) != 0
6187 && GET_CODE (DECL_RTL (DECL_RESULT (current_function_decl))) == REG
6188 && (REGNO (DECL_RTL (DECL_RESULT (current_function_decl)))
6189 >= FIRST_PSEUDO_REGISTER))
6191 rtx real_decl_result;
6193 #ifdef FUNCTION_OUTGOING_VALUE
6195 = FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl)),
6196 current_function_decl);
6199 = FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl)),
6200 current_function_decl);
6202 REG_FUNCTION_VALUE_P (real_decl_result) = 1;
6203 /* If this is a BLKmode structure being returned in registers, then use
6204 the mode computed in expand_return. */
6205 if (GET_MODE (real_decl_result) == BLKmode)
6206 PUT_MODE (real_decl_result,
6207 GET_MODE (DECL_RTL (DECL_RESULT (current_function_decl))));
6208 emit_move_insn (real_decl_result,
6209 DECL_RTL (DECL_RESULT (current_function_decl)));
6210 emit_insn (gen_rtx_USE (VOIDmode, real_decl_result));
6212 /* The delay slot scheduler assumes that current_function_return_rtx
6213 holds the hard register containing the return value, not a temporary
6215 current_function_return_rtx = real_decl_result;
6218 /* If returning a structure, arrange to return the address of the value
6219 in a place where debuggers expect to find it.
6221 If returning a structure PCC style,
6222 the caller also depends on this value.
6223 And current_function_returns_pcc_struct is not necessarily set. */
6224 if (current_function_returns_struct
6225 || current_function_returns_pcc_struct)
6227 rtx value_address = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
6228 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
6229 #ifdef FUNCTION_OUTGOING_VALUE
6231 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
6232 current_function_decl);
6235 = FUNCTION_VALUE (build_pointer_type (type),
6236 current_function_decl);
6239 /* Mark this as a function return value so integrate will delete the
6240 assignment and USE below when inlining this function. */
6241 REG_FUNCTION_VALUE_P (outgoing) = 1;
6243 emit_move_insn (outgoing, value_address);
6244 use_variable (outgoing);
6247 /* If this is an implementation of __throw, do what's necessary to
6248 communicate between __builtin_eh_return and the epilogue. */
6249 expand_eh_return ();
6251 /* Output a return insn if we are using one.
6252 Otherwise, let the rtl chain end here, to drop through
6253 into the epilogue. */
6258 emit_jump_insn (gen_return ());
6263 /* Fix up any gotos that jumped out to the outermost
6264 binding level of the function.
6265 Must follow emitting RETURN_LABEL. */
6267 /* If you have any cleanups to do at this point,
6268 and they need to create temporary variables,
6269 then you will lose. */
6270 expand_fixups (get_insns ());
6273 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
6275 static int *prologue;
6276 static int *epilogue;
6278 /* Create an array that records the INSN_UIDs of INSNS (either a sequence
6279 or a single insn). */
6281 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
6283 record_insns (insns)
6288 if (GET_CODE (insns) == SEQUENCE)
6290 int len = XVECLEN (insns, 0);
6291 vec = (int *) oballoc ((len + 1) * sizeof (int));
6294 vec[len] = INSN_UID (XVECEXP (insns, 0, len));
6298 vec = (int *) oballoc (2 * sizeof (int));
6299 vec[0] = INSN_UID (insns);
6305 /* Determine how many INSN_UIDs in VEC are part of INSN. */
6308 contains (insn, vec)
6314 if (GET_CODE (insn) == INSN
6315 && GET_CODE (PATTERN (insn)) == SEQUENCE)
6318 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
6319 for (j = 0; vec[j]; j++)
6320 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == vec[j])
6326 for (j = 0; vec[j]; j++)
6327 if (INSN_UID (insn) == vec[j])
6332 #endif /* HAVE_prologue || HAVE_epilogue */
6334 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
6335 this into place with notes indicating where the prologue ends and where
6336 the epilogue begins. Update the basic block information when possible. */
6339 thread_prologue_and_epilogue_insns (f)
6340 rtx f ATTRIBUTE_UNUSED;
6342 #ifdef HAVE_prologue
6347 /* The first insn (a NOTE_INSN_DELETED) is followed by zero or more
6348 prologue insns and a NOTE_INSN_PROLOGUE_END. */
6349 emit_note_after (NOTE_INSN_PROLOGUE_END, f);
6350 seq = gen_prologue ();
6351 head = emit_insn_after (seq, f);
6353 /* Include the new prologue insns in the first block. Ignore them
6354 if they form a basic block unto themselves. */
6355 if (x_basic_block_head && n_basic_blocks
6356 && GET_CODE (BLOCK_HEAD (0)) != CODE_LABEL)
6357 BLOCK_HEAD (0) = NEXT_INSN (f);
6359 /* Retain a map of the prologue insns. */
6360 prologue = record_insns (GET_CODE (seq) == SEQUENCE ? seq : head);
6366 #ifdef HAVE_epilogue
6369 rtx insn = get_last_insn ();
6370 rtx prev = prev_nonnote_insn (insn);
6372 /* If we end with a BARRIER, we don't need an epilogue. */
6373 if (! (prev && GET_CODE (prev) == BARRIER))
6379 /* The last basic block ends with a NOTE_INSN_EPILOGUE_BEG, the
6380 epilogue insns, the USE insns at the end of a function,
6381 the jump insn that returns, and then a BARRIER. */
6383 /* Move the USE insns at the end of a function onto a list. */
6385 && GET_CODE (prev) == INSN
6386 && GET_CODE (PATTERN (prev)) == USE)
6389 prev = prev_nonnote_insn (prev);
6391 NEXT_INSN (PREV_INSN (tem)) = NEXT_INSN (tem);
6392 PREV_INSN (NEXT_INSN (tem)) = PREV_INSN (tem);
6395 NEXT_INSN (tem) = first_use;
6396 PREV_INSN (first_use) = tem;
6403 emit_barrier_after (insn);
6405 seq = gen_epilogue ();
6406 tail = emit_jump_insn_after (seq, insn);
6408 /* Insert the USE insns immediately before the return insn, which
6409 must be the first instruction before the final barrier. */
6412 tem = prev_nonnote_insn (get_last_insn ());
6413 NEXT_INSN (PREV_INSN (tem)) = first_use;
6414 PREV_INSN (first_use) = PREV_INSN (tem);
6415 PREV_INSN (tem) = last_use;
6416 NEXT_INSN (last_use) = tem;
6419 emit_note_after (NOTE_INSN_EPILOGUE_BEG, insn);
6421 /* Include the new epilogue insns in the last block. Ignore
6422 them if they form a basic block unto themselves. */
6423 if (x_basic_block_end && n_basic_blocks
6424 && GET_CODE (BLOCK_END (n_basic_blocks - 1)) != JUMP_INSN)
6425 BLOCK_END (n_basic_blocks - 1) = tail;
6427 /* Retain a map of the epilogue insns. */
6428 epilogue = record_insns (GET_CODE (seq) == SEQUENCE ? seq : tail);
6436 /* Reposition the prologue-end and epilogue-begin notes after instruction
6437 scheduling and delayed branch scheduling. */
6440 reposition_prologue_and_epilogue_notes (f)
6441 rtx f ATTRIBUTE_UNUSED;
6443 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
6444 /* Reposition the prologue and epilogue notes. */
6451 register rtx insn, note = 0;
6453 /* Scan from the beginning until we reach the last prologue insn.
6454 We apparently can't depend on basic_block_{head,end} after
6456 for (len = 0; prologue[len]; len++)
6458 for (insn = f; len && insn; insn = NEXT_INSN (insn))
6460 if (GET_CODE (insn) == NOTE)
6462 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
6465 else if ((len -= contains (insn, prologue)) == 0)
6468 /* Find the prologue-end note if we haven't already, and
6469 move it to just after the last prologue insn. */
6472 for (note = insn; (note = NEXT_INSN (note));)
6473 if (GET_CODE (note) == NOTE
6474 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
6478 next = NEXT_INSN (note);
6480 /* Whether or not we can depend on BLOCK_HEAD,
6481 attempt to keep it up-to-date. */
6482 if (BLOCK_HEAD (0) == note)
6483 BLOCK_HEAD (0) = next;
6486 add_insn_after (note, insn);
6493 register rtx insn, note = 0;
6495 /* Scan from the end until we reach the first epilogue insn.
6496 We apparently can't depend on basic_block_{head,end} after
6498 for (len = 0; epilogue[len]; len++)
6500 for (insn = get_last_insn (); len && insn; insn = PREV_INSN (insn))
6502 if (GET_CODE (insn) == NOTE)
6504 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
6507 else if ((len -= contains (insn, epilogue)) == 0)
6509 /* Find the epilogue-begin note if we haven't already, and
6510 move it to just before the first epilogue insn. */
6513 for (note = insn; (note = PREV_INSN (note));)
6514 if (GET_CODE (note) == NOTE
6515 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
6519 /* Whether or not we can depend on BLOCK_HEAD,
6520 attempt to keep it up-to-date. */
6522 && BLOCK_HEAD (n_basic_blocks-1) == insn)
6523 BLOCK_HEAD (n_basic_blocks-1) = note;
6526 add_insn_before (note, insn);
6531 #endif /* HAVE_prologue or HAVE_epilogue */