1 /* Expands front end tree to back end RTL for GNU C-Compiler
2 Copyright (C) 1987, 88, 89, 91-97, 1998 Free Software Foundation, Inc.
4 This file is part of GNU CC.
6 GNU CC is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 GNU CC is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GNU CC; see the file COPYING. If not, write to
18 the Free Software Foundation, 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
22 /* This file handles the generation of rtl code from tree structure
23 at the level of the function as a whole.
24 It creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 `expand_function_start' is called at the beginning of a function,
28 before the function body is parsed, and `expand_function_end' is
29 called after parsing the body.
31 Call `assign_stack_local' to allocate a stack slot for a local variable.
32 This is usually done during the RTL generation for the function body,
33 but it can also be done in the reload pass when a pseudo-register does
34 not get a hard register.
36 Call `put_var_into_stack' when you learn, belatedly, that a variable
37 previously given a pseudo-register must in fact go in the stack.
38 This function changes the DECL_RTL to be a stack slot instead of a reg
39 then scans all the RTL instructions so far generated to correct them. */
51 #include "insn-flags.h"
53 #include "insn-codes.h"
55 #include "hard-reg-set.h"
56 #include "insn-config.h"
59 #include "basic-block.h"
62 #ifndef TRAMPOLINE_ALIGNMENT
63 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
66 /* Some systems use __main in a way incompatible with its use in gcc, in these
67 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
68 give the same symbol without quotes for an alternative entry point. You
69 must define both, or neither. */
71 #define NAME__MAIN "__main"
72 #define SYMBOL__MAIN __main
75 /* Round a value to the lowest integer less than it that is a multiple of
76 the required alignment. Avoid using division in case the value is
77 negative. Assume the alignment is a power of two. */
78 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
80 /* Similar, but round to the next highest integer that meets the
82 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
84 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
85 during rtl generation. If they are different register numbers, this is
86 always true. It may also be true if
87 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
88 generation. See fix_lexical_addr for details. */
90 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
91 #define NEED_SEPARATE_AP
94 /* Number of bytes of args popped by function being compiled on its return.
95 Zero if no bytes are to be popped.
96 May affect compilation of return insn or of function epilogue. */
98 int current_function_pops_args;
100 /* Nonzero if function being compiled needs to be given an address
101 where the value should be stored. */
103 int current_function_returns_struct;
105 /* Nonzero if function being compiled needs to
106 return the address of where it has put a structure value. */
108 int current_function_returns_pcc_struct;
110 /* Nonzero if function being compiled needs to be passed a static chain. */
112 int current_function_needs_context;
114 /* Nonzero if function being compiled can call setjmp. */
116 int current_function_calls_setjmp;
118 /* Nonzero if function being compiled can call longjmp. */
120 int current_function_calls_longjmp;
122 /* Nonzero if function being compiled receives nonlocal gotos
123 from nested functions. */
125 int current_function_has_nonlocal_label;
127 /* Nonzero if function being compiled has nonlocal gotos to parent
130 int current_function_has_nonlocal_goto;
132 /* Nonzero if function being compiled contains nested functions. */
134 int current_function_contains_functions;
136 /* Nonzero if the current function is a thunk (a lightweight function that
137 just adjusts one of its arguments and forwards to another function), so
138 we should try to cut corners where we can. */
139 int current_function_is_thunk;
141 /* Nonzero if function being compiled can call alloca,
142 either as a subroutine or builtin. */
144 int current_function_calls_alloca;
146 /* Nonzero if the current function returns a pointer type */
148 int current_function_returns_pointer;
150 /* If some insns can be deferred to the delay slots of the epilogue, the
151 delay list for them is recorded here. */
153 rtx current_function_epilogue_delay_list;
155 /* If function's args have a fixed size, this is that size, in bytes.
157 May affect compilation of return insn or of function epilogue. */
159 int current_function_args_size;
161 /* # bytes the prologue should push and pretend that the caller pushed them.
162 The prologue must do this, but only if parms can be passed in registers. */
164 int current_function_pretend_args_size;
166 /* # of bytes of outgoing arguments. If ACCUMULATE_OUTGOING_ARGS is
167 defined, the needed space is pushed by the prologue. */
169 int current_function_outgoing_args_size;
171 /* This is the offset from the arg pointer to the place where the first
172 anonymous arg can be found, if there is one. */
174 rtx current_function_arg_offset_rtx;
176 /* Nonzero if current function uses varargs.h or equivalent.
177 Zero for functions that use stdarg.h. */
179 int current_function_varargs;
181 /* Nonzero if current function uses stdarg.h or equivalent.
182 Zero for functions that use varargs.h. */
184 int current_function_stdarg;
186 /* Quantities of various kinds of registers
187 used for the current function's args. */
189 CUMULATIVE_ARGS current_function_args_info;
191 /* Name of function now being compiled. */
193 char *current_function_name;
195 /* If non-zero, an RTL expression for the location at which the current
196 function returns its result. If the current function returns its
197 result in a register, current_function_return_rtx will always be
198 the hard register containing the result. */
200 rtx current_function_return_rtx;
202 /* Nonzero if the current function uses the constant pool. */
204 int current_function_uses_const_pool;
206 /* Nonzero if the current function uses pic_offset_table_rtx. */
207 int current_function_uses_pic_offset_table;
209 /* The arg pointer hard register, or the pseudo into which it was copied. */
210 rtx current_function_internal_arg_pointer;
212 /* The FUNCTION_DECL for an inline function currently being expanded. */
213 tree inline_function_decl;
215 /* Number of function calls seen so far in current function. */
217 int function_call_count;
219 /* List (chain of TREE_LIST) of LABEL_DECLs for all nonlocal labels
220 (labels to which there can be nonlocal gotos from nested functions)
223 tree nonlocal_labels;
225 /* RTX for stack slot that holds the current handler for nonlocal gotos.
226 Zero when function does not have nonlocal labels. */
228 rtx nonlocal_goto_handler_slot;
230 /* RTX for stack slot that holds the stack pointer value to restore
232 Zero when function does not have nonlocal labels. */
234 rtx nonlocal_goto_stack_level;
236 /* Label that will go on parm cleanup code, if any.
237 Jumping to this label runs cleanup code for parameters, if
238 such code must be run. Following this code is the logical return label. */
242 /* Label that will go on function epilogue.
243 Jumping to this label serves as a "return" instruction
244 on machines which require execution of the epilogue on all returns. */
248 /* List (chain of EXPR_LISTs) of pseudo-regs of SAVE_EXPRs.
249 So we can mark them all live at the end of the function, if nonopt. */
252 /* List (chain of EXPR_LISTs) of all stack slots in this function.
253 Made for the sake of unshare_all_rtl. */
256 /* Chain of all RTL_EXPRs that have insns in them. */
259 /* Label to jump back to for tail recursion, or 0 if we have
260 not yet needed one for this function. */
261 rtx tail_recursion_label;
263 /* Place after which to insert the tail_recursion_label if we need one. */
264 rtx tail_recursion_reentry;
266 /* Location at which to save the argument pointer if it will need to be
267 referenced. There are two cases where this is done: if nonlocal gotos
268 exist, or if vars stored at an offset from the argument pointer will be
269 needed by inner routines. */
271 rtx arg_pointer_save_area;
273 /* Offset to end of allocated area of stack frame.
274 If stack grows down, this is the address of the last stack slot allocated.
275 If stack grows up, this is the address for the next slot. */
276 HOST_WIDE_INT frame_offset;
278 /* List (chain of TREE_LISTs) of static chains for containing functions.
279 Each link has a FUNCTION_DECL in the TREE_PURPOSE and a reg rtx
280 in an RTL_EXPR in the TREE_VALUE. */
281 static tree context_display;
283 /* List (chain of TREE_LISTs) of trampolines for nested functions.
284 The trampoline sets up the static chain and jumps to the function.
285 We supply the trampoline's address when the function's address is requested.
287 Each link has a FUNCTION_DECL in the TREE_PURPOSE and a reg rtx
288 in an RTL_EXPR in the TREE_VALUE. */
289 static tree trampoline_list;
291 /* Insn after which register parms and SAVE_EXPRs are born, if nonopt. */
292 static rtx parm_birth_insn;
295 /* Nonzero if a stack slot has been generated whose address is not
296 actually valid. It means that the generated rtl must all be scanned
297 to detect and correct the invalid addresses where they occur. */
298 static int invalid_stack_slot;
301 /* Last insn of those whose job was to put parms into their nominal homes. */
302 static rtx last_parm_insn;
304 /* 1 + last pseudo register number possibly used for loading a copy
305 of a parameter of this function. */
308 /* Vector indexed by REGNO, containing location on stack in which
309 to put the parm which is nominally in pseudo register REGNO,
310 if we discover that that parm must go in the stack. The highest
311 element in this vector is one less than MAX_PARM_REG, above. */
312 rtx *parm_reg_stack_loc;
314 /* Nonzero once virtual register instantiation has been done.
315 assign_stack_local uses frame_pointer_rtx when this is nonzero. */
316 static int virtuals_instantiated;
318 /* These variables hold pointers to functions to
319 save and restore machine-specific data,
320 in push_function_context and pop_function_context. */
321 void (*save_machine_status) PROTO((struct function *));
322 void (*restore_machine_status) PROTO((struct function *));
324 /* Nonzero if we need to distinguish between the return value of this function
325 and the return value of a function called by this function. This helps
328 extern int rtx_equal_function_value_matters;
329 extern tree sequence_rtl_expr;
331 /* In order to evaluate some expressions, such as function calls returning
332 structures in memory, we need to temporarily allocate stack locations.
333 We record each allocated temporary in the following structure.
335 Associated with each temporary slot is a nesting level. When we pop up
336 one level, all temporaries associated with the previous level are freed.
337 Normally, all temporaries are freed after the execution of the statement
338 in which they were created. However, if we are inside a ({...}) grouping,
339 the result may be in a temporary and hence must be preserved. If the
340 result could be in a temporary, we preserve it if we can determine which
341 one it is in. If we cannot determine which temporary may contain the
342 result, all temporaries are preserved. A temporary is preserved by
343 pretending it was allocated at the previous nesting level.
345 Automatic variables are also assigned temporary slots, at the nesting
346 level where they are defined. They are marked a "kept" so that
347 free_temp_slots will not free them. */
351 /* Points to next temporary slot. */
352 struct temp_slot *next;
353 /* The rtx to used to reference the slot. */
355 /* The rtx used to represent the address if not the address of the
356 slot above. May be an EXPR_LIST if multiple addresses exist. */
358 /* The size, in units, of the slot. */
360 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
362 /* Non-zero if this temporary is currently in use. */
364 /* Non-zero if this temporary has its address taken. */
366 /* Nesting level at which this slot is being used. */
368 /* Non-zero if this should survive a call to free_temp_slots. */
370 /* The offset of the slot from the frame_pointer, including extra space
371 for alignment. This info is for combine_temp_slots. */
373 /* The size of the slot, including extra space for alignment. This
374 info is for combine_temp_slots. */
378 /* List of all temporaries allocated, both available and in use. */
380 struct temp_slot *temp_slots;
382 /* Current nesting level for temporaries. */
386 /* This structure is used to record MEMs or pseudos used to replace VAR, any
387 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
388 maintain this list in case two operands of an insn were required to match;
389 in that case we must ensure we use the same replacement. */
391 struct fixup_replacement
395 struct fixup_replacement *next;
398 /* Forward declarations. */
400 static struct temp_slot *find_temp_slot_from_address PROTO((rtx));
401 static void put_reg_into_stack PROTO((struct function *, rtx, tree,
402 enum machine_mode, enum machine_mode,
404 static void fixup_var_refs PROTO((rtx, enum machine_mode, int));
405 static struct fixup_replacement
406 *find_fixup_replacement PROTO((struct fixup_replacement **, rtx));
407 static void fixup_var_refs_insns PROTO((rtx, enum machine_mode, int,
409 static void fixup_var_refs_1 PROTO((rtx, enum machine_mode, rtx *, rtx,
410 struct fixup_replacement **));
411 static rtx fixup_memory_subreg PROTO((rtx, rtx, int));
412 static rtx walk_fixup_memory_subreg PROTO((rtx, rtx, int));
413 static rtx fixup_stack_1 PROTO((rtx, rtx));
414 static void optimize_bit_field PROTO((rtx, rtx, rtx *));
415 static void instantiate_decls PROTO((tree, int));
416 static void instantiate_decls_1 PROTO((tree, int));
417 static void instantiate_decl PROTO((rtx, int, int));
418 static int instantiate_virtual_regs_1 PROTO((rtx *, rtx, int));
419 static void delete_handlers PROTO((void));
420 static void pad_to_arg_alignment PROTO((struct args_size *, int));
421 #ifndef ARGS_GROW_DOWNWARD
422 static void pad_below PROTO((struct args_size *, enum machine_mode,
425 static tree round_down PROTO((tree, int));
426 static rtx round_trampoline_addr PROTO((rtx));
427 static tree blocks_nreverse PROTO((tree));
428 static int all_blocks PROTO((tree, tree *));
429 static int *record_insns PROTO((rtx));
430 static int contains PROTO((rtx, int *));
431 static void put_addressof_into_stack PROTO((rtx));
432 static void purge_addressof_1 PROTO((rtx *, rtx, int));
434 /* Pointer to chain of `struct function' for containing functions. */
435 struct function *outer_function_chain;
437 /* Given a function decl for a containing function,
438 return the `struct function' for it. */
441 find_function_data (decl)
445 for (p = outer_function_chain; p; p = p->next)
451 /* Save the current context for compilation of a nested function.
452 This is called from language-specific code.
453 The caller is responsible for saving any language-specific status,
454 since this function knows only about language-independent variables. */
457 push_function_context_to (context)
460 struct function *p = (struct function *) xmalloc (sizeof (struct function));
462 p->next = outer_function_chain;
463 outer_function_chain = p;
465 p->name = current_function_name;
466 p->decl = current_function_decl;
467 p->pops_args = current_function_pops_args;
468 p->returns_struct = current_function_returns_struct;
469 p->returns_pcc_struct = current_function_returns_pcc_struct;
470 p->returns_pointer = current_function_returns_pointer;
471 p->needs_context = current_function_needs_context;
472 p->calls_setjmp = current_function_calls_setjmp;
473 p->calls_longjmp = current_function_calls_longjmp;
474 p->calls_alloca = current_function_calls_alloca;
475 p->has_nonlocal_label = current_function_has_nonlocal_label;
476 p->has_nonlocal_goto = current_function_has_nonlocal_goto;
477 p->contains_functions = current_function_contains_functions;
478 p->is_thunk = current_function_is_thunk;
479 p->args_size = current_function_args_size;
480 p->pretend_args_size = current_function_pretend_args_size;
481 p->arg_offset_rtx = current_function_arg_offset_rtx;
482 p->varargs = current_function_varargs;
483 p->stdarg = current_function_stdarg;
484 p->uses_const_pool = current_function_uses_const_pool;
485 p->uses_pic_offset_table = current_function_uses_pic_offset_table;
486 p->internal_arg_pointer = current_function_internal_arg_pointer;
487 p->max_parm_reg = max_parm_reg;
488 p->parm_reg_stack_loc = parm_reg_stack_loc;
489 p->outgoing_args_size = current_function_outgoing_args_size;
490 p->return_rtx = current_function_return_rtx;
491 p->nonlocal_goto_handler_slot = nonlocal_goto_handler_slot;
492 p->nonlocal_goto_stack_level = nonlocal_goto_stack_level;
493 p->nonlocal_labels = nonlocal_labels;
494 p->cleanup_label = cleanup_label;
495 p->return_label = return_label;
496 p->save_expr_regs = save_expr_regs;
497 p->stack_slot_list = stack_slot_list;
498 p->parm_birth_insn = parm_birth_insn;
499 p->frame_offset = frame_offset;
500 p->tail_recursion_label = tail_recursion_label;
501 p->tail_recursion_reentry = tail_recursion_reentry;
502 p->arg_pointer_save_area = arg_pointer_save_area;
503 p->rtl_expr_chain = rtl_expr_chain;
504 p->last_parm_insn = last_parm_insn;
505 p->context_display = context_display;
506 p->trampoline_list = trampoline_list;
507 p->function_call_count = function_call_count;
508 p->temp_slots = temp_slots;
509 p->temp_slot_level = temp_slot_level;
510 p->fixup_var_refs_queue = 0;
511 p->epilogue_delay_list = current_function_epilogue_delay_list;
512 p->args_info = current_function_args_info;
514 save_tree_status (p, context);
515 save_storage_status (p);
516 save_emit_status (p);
518 save_expr_status (p);
519 save_stmt_status (p);
520 save_varasm_status (p, context);
522 if (save_machine_status)
523 (*save_machine_status) (p);
527 push_function_context ()
529 push_function_context_to (current_function_decl);
532 /* Restore the last saved context, at the end of a nested function.
533 This function is called from language-specific code. */
536 pop_function_context_from (context)
539 struct function *p = outer_function_chain;
541 outer_function_chain = p->next;
543 current_function_contains_functions
544 = p->contains_functions || p->inline_obstacks
545 || context == current_function_decl;
546 current_function_name = p->name;
547 current_function_decl = p->decl;
548 current_function_pops_args = p->pops_args;
549 current_function_returns_struct = p->returns_struct;
550 current_function_returns_pcc_struct = p->returns_pcc_struct;
551 current_function_returns_pointer = p->returns_pointer;
552 current_function_needs_context = p->needs_context;
553 current_function_calls_setjmp = p->calls_setjmp;
554 current_function_calls_longjmp = p->calls_longjmp;
555 current_function_calls_alloca = p->calls_alloca;
556 current_function_has_nonlocal_label = p->has_nonlocal_label;
557 current_function_has_nonlocal_goto = p->has_nonlocal_goto;
558 current_function_is_thunk = p->is_thunk;
559 current_function_args_size = p->args_size;
560 current_function_pretend_args_size = p->pretend_args_size;
561 current_function_arg_offset_rtx = p->arg_offset_rtx;
562 current_function_varargs = p->varargs;
563 current_function_stdarg = p->stdarg;
564 current_function_uses_const_pool = p->uses_const_pool;
565 current_function_uses_pic_offset_table = p->uses_pic_offset_table;
566 current_function_internal_arg_pointer = p->internal_arg_pointer;
567 max_parm_reg = p->max_parm_reg;
568 parm_reg_stack_loc = p->parm_reg_stack_loc;
569 current_function_outgoing_args_size = p->outgoing_args_size;
570 current_function_return_rtx = p->return_rtx;
571 nonlocal_goto_handler_slot = p->nonlocal_goto_handler_slot;
572 nonlocal_goto_stack_level = p->nonlocal_goto_stack_level;
573 nonlocal_labels = p->nonlocal_labels;
574 cleanup_label = p->cleanup_label;
575 return_label = p->return_label;
576 save_expr_regs = p->save_expr_regs;
577 stack_slot_list = p->stack_slot_list;
578 parm_birth_insn = p->parm_birth_insn;
579 frame_offset = p->frame_offset;
580 tail_recursion_label = p->tail_recursion_label;
581 tail_recursion_reentry = p->tail_recursion_reentry;
582 arg_pointer_save_area = p->arg_pointer_save_area;
583 rtl_expr_chain = p->rtl_expr_chain;
584 last_parm_insn = p->last_parm_insn;
585 context_display = p->context_display;
586 trampoline_list = p->trampoline_list;
587 function_call_count = p->function_call_count;
588 temp_slots = p->temp_slots;
589 temp_slot_level = p->temp_slot_level;
590 current_function_epilogue_delay_list = p->epilogue_delay_list;
592 current_function_args_info = p->args_info;
594 restore_tree_status (p, context);
595 restore_storage_status (p);
596 restore_expr_status (p);
597 restore_emit_status (p);
598 restore_stmt_status (p);
599 restore_varasm_status (p);
601 if (restore_machine_status)
602 (*restore_machine_status) (p);
604 /* Finish doing put_var_into_stack for any of our variables
605 which became addressable during the nested function. */
607 struct var_refs_queue *queue = p->fixup_var_refs_queue;
608 for (; queue; queue = queue->next)
609 fixup_var_refs (queue->modified, queue->promoted_mode, queue->unsignedp);
614 /* Reset variables that have known state during rtx generation. */
615 rtx_equal_function_value_matters = 1;
616 virtuals_instantiated = 0;
619 void pop_function_context ()
621 pop_function_context_from (current_function_decl);
624 /* Allocate fixed slots in the stack frame of the current function. */
626 /* Return size needed for stack frame based on slots so far allocated.
627 This size counts from zero. It is not rounded to STACK_BOUNDARY;
628 the caller may have to do that. */
633 #ifdef FRAME_GROWS_DOWNWARD
634 return -frame_offset;
640 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
641 with machine mode MODE.
643 ALIGN controls the amount of alignment for the address of the slot:
644 0 means according to MODE,
645 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
646 positive specifies alignment boundary in bits.
648 We do not round to stack_boundary here. */
651 assign_stack_local (mode, size, align)
652 enum machine_mode mode;
656 register rtx x, addr;
657 int bigend_correction = 0;
662 alignment = GET_MODE_ALIGNMENT (mode) / BITS_PER_UNIT;
664 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
666 else if (align == -1)
668 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
669 size = CEIL_ROUND (size, alignment);
672 alignment = align / BITS_PER_UNIT;
674 /* Round frame offset to that alignment.
675 We must be careful here, since FRAME_OFFSET might be negative and
676 division with a negative dividend isn't as well defined as we might
677 like. So we instead assume that ALIGNMENT is a power of two and
678 use logical operations which are unambiguous. */
679 #ifdef FRAME_GROWS_DOWNWARD
680 frame_offset = FLOOR_ROUND (frame_offset, alignment);
682 frame_offset = CEIL_ROUND (frame_offset, alignment);
685 /* On a big-endian machine, if we are allocating more space than we will use,
686 use the least significant bytes of those that are allocated. */
687 if (BYTES_BIG_ENDIAN && mode != BLKmode)
688 bigend_correction = size - GET_MODE_SIZE (mode);
690 #ifdef FRAME_GROWS_DOWNWARD
691 frame_offset -= size;
694 /* If we have already instantiated virtual registers, return the actual
695 address relative to the frame pointer. */
696 if (virtuals_instantiated)
697 addr = plus_constant (frame_pointer_rtx,
698 (frame_offset + bigend_correction
699 + STARTING_FRAME_OFFSET));
701 addr = plus_constant (virtual_stack_vars_rtx,
702 frame_offset + bigend_correction);
704 #ifndef FRAME_GROWS_DOWNWARD
705 frame_offset += size;
708 x = gen_rtx_MEM (mode, addr);
710 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, x, stack_slot_list);
715 /* Assign a stack slot in a containing function.
716 First three arguments are same as in preceding function.
717 The last argument specifies the function to allocate in. */
720 assign_outer_stack_local (mode, size, align, function)
721 enum machine_mode mode;
724 struct function *function;
726 register rtx x, addr;
727 int bigend_correction = 0;
730 /* Allocate in the memory associated with the function in whose frame
732 push_obstacks (function->function_obstack,
733 function->function_maybepermanent_obstack);
737 alignment = GET_MODE_ALIGNMENT (mode) / BITS_PER_UNIT;
739 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
741 else if (align == -1)
743 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
744 size = CEIL_ROUND (size, alignment);
747 alignment = align / BITS_PER_UNIT;
749 /* Round frame offset to that alignment. */
750 #ifdef FRAME_GROWS_DOWNWARD
751 function->frame_offset = FLOOR_ROUND (function->frame_offset, alignment);
753 function->frame_offset = CEIL_ROUND (function->frame_offset, alignment);
756 /* On a big-endian machine, if we are allocating more space than we will use,
757 use the least significant bytes of those that are allocated. */
758 if (BYTES_BIG_ENDIAN && mode != BLKmode)
759 bigend_correction = size - GET_MODE_SIZE (mode);
761 #ifdef FRAME_GROWS_DOWNWARD
762 function->frame_offset -= size;
764 addr = plus_constant (virtual_stack_vars_rtx,
765 function->frame_offset + bigend_correction);
766 #ifndef FRAME_GROWS_DOWNWARD
767 function->frame_offset += size;
770 x = gen_rtx_MEM (mode, addr);
772 function->stack_slot_list
773 = gen_rtx_EXPR_LIST (VOIDmode, x, function->stack_slot_list);
780 /* Allocate a temporary stack slot and record it for possible later
783 MODE is the machine mode to be given to the returned rtx.
785 SIZE is the size in units of the space required. We do no rounding here
786 since assign_stack_local will do any required rounding.
788 KEEP is 1 if this slot is to be retained after a call to
789 free_temp_slots. Automatic variables for a block are allocated
790 with this flag. KEEP is 2, if we allocate a longer term temporary,
791 whose lifetime is controlled by CLEANUP_POINT_EXPRs. */
794 assign_stack_temp (mode, size, keep)
795 enum machine_mode mode;
799 struct temp_slot *p, *best_p = 0;
801 /* If SIZE is -1 it means that somebody tried to allocate a temporary
802 of a variable size. */
806 /* First try to find an available, already-allocated temporary that is the
807 exact size we require. */
808 for (p = temp_slots; p; p = p->next)
809 if (p->size == size && GET_MODE (p->slot) == mode && ! p->in_use)
812 /* If we didn't find, one, try one that is larger than what we want. We
813 find the smallest such. */
815 for (p = temp_slots; p; p = p->next)
816 if (p->size > size && GET_MODE (p->slot) == mode && ! p->in_use
817 && (best_p == 0 || best_p->size > p->size))
820 /* Make our best, if any, the one to use. */
823 /* If there are enough aligned bytes left over, make them into a new
824 temp_slot so that the extra bytes don't get wasted. Do this only
825 for BLKmode slots, so that we can be sure of the alignment. */
826 if (GET_MODE (best_p->slot) == BLKmode)
828 int alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
829 int rounded_size = CEIL_ROUND (size, alignment);
831 if (best_p->size - rounded_size >= alignment)
833 p = (struct temp_slot *) oballoc (sizeof (struct temp_slot));
834 p->in_use = p->addr_taken = 0;
835 p->size = best_p->size - rounded_size;
836 p->base_offset = best_p->base_offset + rounded_size;
837 p->full_size = best_p->full_size - rounded_size;
838 p->slot = gen_rtx_MEM (BLKmode,
839 plus_constant (XEXP (best_p->slot, 0),
843 p->next = temp_slots;
846 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
849 best_p->size = rounded_size;
850 best_p->full_size = rounded_size;
857 /* If we still didn't find one, make a new temporary. */
860 int frame_offset_old = frame_offset;
861 p = (struct temp_slot *) oballoc (sizeof (struct temp_slot));
862 /* If the temp slot mode doesn't indicate the alignment,
863 use the largest possible, so no one will be disappointed. */
864 p->slot = assign_stack_local (mode, size, mode == BLKmode ? -1 : 0);
865 /* The following slot size computation is necessary because we don't
866 know the actual size of the temporary slot until assign_stack_local
867 has performed all the frame alignment and size rounding for the
868 requested temporary. Note that extra space added for alignment
869 can be either above or below this stack slot depending on which
870 way the frame grows. We include the extra space if and only if it
871 is above this slot. */
872 #ifdef FRAME_GROWS_DOWNWARD
873 p->size = frame_offset_old - frame_offset;
877 /* Now define the fields used by combine_temp_slots. */
878 #ifdef FRAME_GROWS_DOWNWARD
879 p->base_offset = frame_offset;
880 p->full_size = frame_offset_old - frame_offset;
882 p->base_offset = frame_offset_old;
883 p->full_size = frame_offset - frame_offset_old;
886 p->next = temp_slots;
892 p->rtl_expr = sequence_rtl_expr;
896 p->level = target_temp_slot_level;
901 p->level = temp_slot_level;
905 /* We may be reusing an old slot, so clear any MEM flags that may have been
907 RTX_UNCHANGING_P (p->slot) = 0;
908 MEM_IN_STRUCT_P (p->slot) = 0;
912 /* Assign a temporary of given TYPE.
913 KEEP is as for assign_stack_temp.
914 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
915 it is 0 if a register is OK.
916 DONT_PROMOTE is 1 if we should not promote values in register
920 assign_temp (type, keep, memory_required, dont_promote)
926 enum machine_mode mode = TYPE_MODE (type);
927 int unsignedp = TREE_UNSIGNED (type);
929 if (mode == BLKmode || memory_required)
931 int size = int_size_in_bytes (type);
934 /* Unfortunately, we don't yet know how to allocate variable-sized
935 temporaries. However, sometimes we have a fixed upper limit on
936 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
937 instead. This is the case for Chill variable-sized strings. */
938 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
939 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
940 && TREE_CODE (TYPE_ARRAY_MAX_SIZE (type)) == INTEGER_CST)
941 size = TREE_INT_CST_LOW (TYPE_ARRAY_MAX_SIZE (type));
943 tmp = assign_stack_temp (mode, size, keep);
944 MEM_IN_STRUCT_P (tmp) = AGGREGATE_TYPE_P (type);
948 #ifndef PROMOTE_FOR_CALL_ONLY
950 mode = promote_mode (type, mode, &unsignedp, 0);
953 return gen_reg_rtx (mode);
956 /* Combine temporary stack slots which are adjacent on the stack.
958 This allows for better use of already allocated stack space. This is only
959 done for BLKmode slots because we can be sure that we won't have alignment
960 problems in this case. */
963 combine_temp_slots ()
965 struct temp_slot *p, *q;
966 struct temp_slot *prev_p, *prev_q;
967 /* Determine where to free back to after this function. */
968 rtx free_pointer = rtx_alloc (CONST_INT);
970 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
973 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
974 for (q = p->next, prev_q = p; q; q = prev_q->next)
977 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
979 if (p->base_offset + p->full_size == q->base_offset)
981 /* Q comes after P; combine Q into P. */
983 p->full_size += q->full_size;
986 else if (q->base_offset + q->full_size == p->base_offset)
988 /* P comes after Q; combine P into Q. */
990 q->full_size += p->full_size;
995 /* Either delete Q or advance past it. */
997 prev_q->next = q->next;
1001 /* Either delete P or advance past it. */
1005 prev_p->next = p->next;
1007 temp_slots = p->next;
1013 /* Free all the RTL made by plus_constant. */
1014 rtx_free (free_pointer);
1017 /* Find the temp slot corresponding to the object at address X. */
1019 static struct temp_slot *
1020 find_temp_slot_from_address (x)
1023 struct temp_slot *p;
1026 for (p = temp_slots; p; p = p->next)
1030 else if (XEXP (p->slot, 0) == x
1032 || (GET_CODE (x) == PLUS
1033 && XEXP (x, 0) == virtual_stack_vars_rtx
1034 && GET_CODE (XEXP (x, 1)) == CONST_INT
1035 && INTVAL (XEXP (x, 1)) >= p->base_offset
1036 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
1039 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
1040 for (next = p->address; next; next = XEXP (next, 1))
1041 if (XEXP (next, 0) == x)
1048 /* Indicate that NEW is an alternate way of referring to the temp slot
1049 that previous was known by OLD. */
1052 update_temp_slot_address (old, new)
1055 struct temp_slot *p = find_temp_slot_from_address (old);
1057 /* If none, return. Else add NEW as an alias. */
1060 else if (p->address == 0)
1064 if (GET_CODE (p->address) != EXPR_LIST)
1065 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1067 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1071 /* If X could be a reference to a temporary slot, mark the fact that its
1072 address was taken. */
1075 mark_temp_addr_taken (x)
1078 struct temp_slot *p;
1083 /* If X is not in memory or is at a constant address, it cannot be in
1084 a temporary slot. */
1085 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1088 p = find_temp_slot_from_address (XEXP (x, 0));
1093 /* If X could be a reference to a temporary slot, mark that slot as
1094 belonging to the to one level higher than the current level. If X
1095 matched one of our slots, just mark that one. Otherwise, we can't
1096 easily predict which it is, so upgrade all of them. Kept slots
1097 need not be touched.
1099 This is called when an ({...}) construct occurs and a statement
1100 returns a value in memory. */
1103 preserve_temp_slots (x)
1106 struct temp_slot *p = 0;
1108 /* If there is no result, we still might have some objects whose address
1109 were taken, so we need to make sure they stay around. */
1112 for (p = temp_slots; p; p = p->next)
1113 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1119 /* If X is a register that is being used as a pointer, see if we have
1120 a temporary slot we know it points to. To be consistent with
1121 the code below, we really should preserve all non-kept slots
1122 if we can't find a match, but that seems to be much too costly. */
1123 if (GET_CODE (x) == REG && REGNO_POINTER_FLAG (REGNO (x)))
1124 p = find_temp_slot_from_address (x);
1126 /* If X is not in memory or is at a constant address, it cannot be in
1127 a temporary slot, but it can contain something whose address was
1129 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1131 for (p = temp_slots; p; p = p->next)
1132 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1138 /* First see if we can find a match. */
1140 p = find_temp_slot_from_address (XEXP (x, 0));
1144 /* Move everything at our level whose address was taken to our new
1145 level in case we used its address. */
1146 struct temp_slot *q;
1148 if (p->level == temp_slot_level)
1150 for (q = temp_slots; q; q = q->next)
1151 if (q != p && q->addr_taken && q->level == p->level)
1160 /* Otherwise, preserve all non-kept slots at this level. */
1161 for (p = temp_slots; p; p = p->next)
1162 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1166 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1167 with that RTL_EXPR, promote it into a temporary slot at the present
1168 level so it will not be freed when we free slots made in the
1172 preserve_rtl_expr_result (x)
1175 struct temp_slot *p;
1177 /* If X is not in memory or is at a constant address, it cannot be in
1178 a temporary slot. */
1179 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1182 /* If we can find a match, move it to our level unless it is already at
1184 p = find_temp_slot_from_address (XEXP (x, 0));
1187 p->level = MIN (p->level, temp_slot_level);
1194 /* Free all temporaries used so far. This is normally called at the end
1195 of generating code for a statement. Don't free any temporaries
1196 currently in use for an RTL_EXPR that hasn't yet been emitted.
1197 We could eventually do better than this since it can be reused while
1198 generating the same RTL_EXPR, but this is complex and probably not
1204 struct temp_slot *p;
1206 for (p = temp_slots; p; p = p->next)
1207 if (p->in_use && p->level == temp_slot_level && ! p->keep
1208 && p->rtl_expr == 0)
1211 combine_temp_slots ();
1214 /* Free all temporary slots used in T, an RTL_EXPR node. */
1217 free_temps_for_rtl_expr (t)
1220 struct temp_slot *p;
1222 for (p = temp_slots; p; p = p->next)
1223 if (p->rtl_expr == t)
1226 combine_temp_slots ();
1229 /* Mark all temporaries ever allocated in this function as not suitable
1230 for reuse until the current level is exited. */
1233 mark_all_temps_used ()
1235 struct temp_slot *p;
1237 for (p = temp_slots; p; p = p->next)
1239 p->in_use = p->keep = 1;
1240 p->level = MIN (p->level, temp_slot_level);
1244 /* Push deeper into the nesting level for stack temporaries. */
1252 /* Pop a temporary nesting level. All slots in use in the current level
1258 struct temp_slot *p;
1260 for (p = temp_slots; p; p = p->next)
1261 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1264 combine_temp_slots ();
1269 /* Initialize temporary slots. */
1274 /* We have not allocated any temporaries yet. */
1276 temp_slot_level = 0;
1277 target_temp_slot_level = 0;
1280 /* Retroactively move an auto variable from a register to a stack slot.
1281 This is done when an address-reference to the variable is seen. */
1284 put_var_into_stack (decl)
1288 enum machine_mode promoted_mode, decl_mode;
1289 struct function *function = 0;
1291 int can_use_addressof;
1293 context = decl_function_context (decl);
1295 /* Get the current rtl used for this object and it's original mode. */
1296 reg = TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl) : DECL_RTL (decl);
1298 /* No need to do anything if decl has no rtx yet
1299 since in that case caller is setting TREE_ADDRESSABLE
1300 and a stack slot will be assigned when the rtl is made. */
1304 /* Get the declared mode for this object. */
1305 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1306 : DECL_MODE (decl));
1307 /* Get the mode it's actually stored in. */
1308 promoted_mode = GET_MODE (reg);
1310 /* If this variable comes from an outer function,
1311 find that function's saved context. */
1312 if (context != current_function_decl && context != inline_function_decl)
1313 for (function = outer_function_chain; function; function = function->next)
1314 if (function->decl == context)
1317 /* If this is a variable-size object with a pseudo to address it,
1318 put that pseudo into the stack, if the var is nonlocal. */
1319 if (DECL_NONLOCAL (decl)
1320 && GET_CODE (reg) == MEM
1321 && GET_CODE (XEXP (reg, 0)) == REG
1322 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1324 reg = XEXP (reg, 0);
1325 decl_mode = promoted_mode = GET_MODE (reg);
1330 /* FIXME make it work for promoted modes too */
1331 && decl_mode == promoted_mode
1332 #ifdef NON_SAVING_SETJMP
1333 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1337 /* If we can't use ADDRESSOF, make sure we see through one we already
1339 if (! can_use_addressof && GET_CODE (reg) == MEM
1340 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1341 reg = XEXP (XEXP (reg, 0), 0);
1343 /* Now we should have a value that resides in one or more pseudo regs. */
1345 if (GET_CODE (reg) == REG)
1347 /* If this variable lives in the current function and we don't need
1348 to put things in the stack for the sake of setjmp, try to keep it
1349 in a register until we know we actually need the address. */
1350 if (can_use_addressof)
1351 gen_mem_addressof (reg, decl);
1353 put_reg_into_stack (function, reg, TREE_TYPE (decl),
1354 promoted_mode, decl_mode,
1355 TREE_SIDE_EFFECTS (decl), 0);
1357 else if (GET_CODE (reg) == CONCAT)
1359 /* A CONCAT contains two pseudos; put them both in the stack.
1360 We do it so they end up consecutive. */
1361 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1362 tree part_type = TREE_TYPE (TREE_TYPE (decl));
1363 #ifdef FRAME_GROWS_DOWNWARD
1364 /* Since part 0 should have a lower address, do it second. */
1365 put_reg_into_stack (function, XEXP (reg, 1), part_type, part_mode,
1366 part_mode, TREE_SIDE_EFFECTS (decl), 0);
1367 put_reg_into_stack (function, XEXP (reg, 0), part_type, part_mode,
1368 part_mode, TREE_SIDE_EFFECTS (decl), 0);
1370 put_reg_into_stack (function, XEXP (reg, 0), part_type, part_mode,
1371 part_mode, TREE_SIDE_EFFECTS (decl), 0);
1372 put_reg_into_stack (function, XEXP (reg, 1), part_type, part_mode,
1373 part_mode, TREE_SIDE_EFFECTS (decl), 0);
1376 /* Change the CONCAT into a combined MEM for both parts. */
1377 PUT_CODE (reg, MEM);
1378 MEM_VOLATILE_P (reg) = MEM_VOLATILE_P (XEXP (reg, 0));
1380 /* The two parts are in memory order already.
1381 Use the lower parts address as ours. */
1382 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1383 /* Prevent sharing of rtl that might lose. */
1384 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1385 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1390 if (flag_check_memory_usage)
1391 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
1392 XEXP (reg, 0), ptr_mode,
1393 GEN_INT (GET_MODE_SIZE (GET_MODE (reg))),
1394 TYPE_MODE (sizetype),
1395 GEN_INT (MEMORY_USE_RW),
1396 TYPE_MODE (integer_type_node));
1399 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1400 into the stack frame of FUNCTION (0 means the current function).
1401 DECL_MODE is the machine mode of the user-level data type.
1402 PROMOTED_MODE is the machine mode of the register.
1403 VOLATILE_P is nonzero if this is for a "volatile" decl. */
1406 put_reg_into_stack (function, reg, type, promoted_mode, decl_mode, volatile_p,
1408 struct function *function;
1411 enum machine_mode promoted_mode, decl_mode;
1416 int regno = original_regno;
1419 regno = REGNO (reg);
1423 if (regno < function->max_parm_reg)
1424 new = function->parm_reg_stack_loc[regno];
1426 new = assign_outer_stack_local (decl_mode, GET_MODE_SIZE (decl_mode),
1431 if (regno < max_parm_reg)
1432 new = parm_reg_stack_loc[regno];
1434 new = assign_stack_local (decl_mode, GET_MODE_SIZE (decl_mode), 0);
1437 PUT_MODE (reg, decl_mode);
1438 XEXP (reg, 0) = XEXP (new, 0);
1439 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1440 MEM_VOLATILE_P (reg) = volatile_p;
1441 PUT_CODE (reg, MEM);
1443 /* If this is a memory ref that contains aggregate components,
1444 mark it as such for cse and loop optimize. */
1445 MEM_IN_STRUCT_P (reg) = AGGREGATE_TYPE_P (type);
1447 /* Now make sure that all refs to the variable, previously made
1448 when it was a register, are fixed up to be valid again. */
1451 struct var_refs_queue *temp;
1453 /* Variable is inherited; fix it up when we get back to its function. */
1454 push_obstacks (function->function_obstack,
1455 function->function_maybepermanent_obstack);
1457 /* See comment in restore_tree_status in tree.c for why this needs to be
1458 on saveable obstack. */
1460 = (struct var_refs_queue *) savealloc (sizeof (struct var_refs_queue));
1461 temp->modified = reg;
1462 temp->promoted_mode = promoted_mode;
1463 temp->unsignedp = TREE_UNSIGNED (type);
1464 temp->next = function->fixup_var_refs_queue;
1465 function->fixup_var_refs_queue = temp;
1469 /* Variable is local; fix it up now. */
1470 fixup_var_refs (reg, promoted_mode, TREE_UNSIGNED (type));
1474 fixup_var_refs (var, promoted_mode, unsignedp)
1476 enum machine_mode promoted_mode;
1480 rtx first_insn = get_insns ();
1481 struct sequence_stack *stack = sequence_stack;
1482 tree rtl_exps = rtl_expr_chain;
1484 /* Must scan all insns for stack-refs that exceed the limit. */
1485 fixup_var_refs_insns (var, promoted_mode, unsignedp, first_insn, stack == 0);
1487 /* Scan all pending sequences too. */
1488 for (; stack; stack = stack->next)
1490 push_to_sequence (stack->first);
1491 fixup_var_refs_insns (var, promoted_mode, unsignedp,
1492 stack->first, stack->next != 0);
1493 /* Update remembered end of sequence
1494 in case we added an insn at the end. */
1495 stack->last = get_last_insn ();
1499 /* Scan all waiting RTL_EXPRs too. */
1500 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1502 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1503 if (seq != const0_rtx && seq != 0)
1505 push_to_sequence (seq);
1506 fixup_var_refs_insns (var, promoted_mode, unsignedp, seq, 0);
1512 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1513 some part of an insn. Return a struct fixup_replacement whose OLD
1514 value is equal to X. Allocate a new structure if no such entry exists. */
1516 static struct fixup_replacement *
1517 find_fixup_replacement (replacements, x)
1518 struct fixup_replacement **replacements;
1521 struct fixup_replacement *p;
1523 /* See if we have already replaced this. */
1524 for (p = *replacements; p && p->old != x; p = p->next)
1529 p = (struct fixup_replacement *) oballoc (sizeof (struct fixup_replacement));
1532 p->next = *replacements;
1539 /* Scan the insn-chain starting with INSN for refs to VAR
1540 and fix them up. TOPLEVEL is nonzero if this chain is the
1541 main chain of insns for the current function. */
1544 fixup_var_refs_insns (var, promoted_mode, unsignedp, insn, toplevel)
1546 enum machine_mode promoted_mode;
1555 rtx next = NEXT_INSN (insn);
1557 if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
1559 /* If this is a CLOBBER of VAR, delete it.
1561 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1562 and REG_RETVAL notes too. */
1563 if (GET_CODE (PATTERN (insn)) == CLOBBER
1564 && XEXP (PATTERN (insn), 0) == var)
1566 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1567 /* The REG_LIBCALL note will go away since we are going to
1568 turn INSN into a NOTE, so just delete the
1569 corresponding REG_RETVAL note. */
1570 remove_note (XEXP (note, 0),
1571 find_reg_note (XEXP (note, 0), REG_RETVAL,
1574 /* In unoptimized compilation, we shouldn't call delete_insn
1575 except in jump.c doing warnings. */
1576 PUT_CODE (insn, NOTE);
1577 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1578 NOTE_SOURCE_FILE (insn) = 0;
1581 /* The insn to load VAR from a home in the arglist
1582 is now a no-op. When we see it, just delete it. */
1584 && GET_CODE (PATTERN (insn)) == SET
1585 && SET_DEST (PATTERN (insn)) == var
1586 /* If this represents the result of an insn group,
1587 don't delete the insn. */
1588 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1589 && rtx_equal_p (SET_SRC (PATTERN (insn)), var))
1591 /* In unoptimized compilation, we shouldn't call delete_insn
1592 except in jump.c doing warnings. */
1593 PUT_CODE (insn, NOTE);
1594 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1595 NOTE_SOURCE_FILE (insn) = 0;
1596 if (insn == last_parm_insn)
1597 last_parm_insn = PREV_INSN (next);
1601 struct fixup_replacement *replacements = 0;
1602 rtx next_insn = NEXT_INSN (insn);
1604 if (SMALL_REGISTER_CLASSES)
1606 /* If the insn that copies the results of a CALL_INSN
1607 into a pseudo now references VAR, we have to use an
1608 intermediate pseudo since we want the life of the
1609 return value register to be only a single insn.
1611 If we don't use an intermediate pseudo, such things as
1612 address computations to make the address of VAR valid
1613 if it is not can be placed between the CALL_INSN and INSN.
1615 To make sure this doesn't happen, we record the destination
1616 of the CALL_INSN and see if the next insn uses both that
1619 if (call_dest != 0 && GET_CODE (insn) == INSN
1620 && reg_mentioned_p (var, PATTERN (insn))
1621 && reg_mentioned_p (call_dest, PATTERN (insn)))
1623 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1625 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1627 PATTERN (insn) = replace_rtx (PATTERN (insn),
1631 if (GET_CODE (insn) == CALL_INSN
1632 && GET_CODE (PATTERN (insn)) == SET)
1633 call_dest = SET_DEST (PATTERN (insn));
1634 else if (GET_CODE (insn) == CALL_INSN
1635 && GET_CODE (PATTERN (insn)) == PARALLEL
1636 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1637 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1642 /* See if we have to do anything to INSN now that VAR is in
1643 memory. If it needs to be loaded into a pseudo, use a single
1644 pseudo for the entire insn in case there is a MATCH_DUP
1645 between two operands. We pass a pointer to the head of
1646 a list of struct fixup_replacements. If fixup_var_refs_1
1647 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1648 it will record them in this list.
1650 If it allocated a pseudo for any replacement, we copy into
1653 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1656 /* If this is last_parm_insn, and any instructions were output
1657 after it to fix it up, then we must set last_parm_insn to
1658 the last such instruction emitted. */
1659 if (insn == last_parm_insn)
1660 last_parm_insn = PREV_INSN (next_insn);
1662 while (replacements)
1664 if (GET_CODE (replacements->new) == REG)
1669 /* OLD might be a (subreg (mem)). */
1670 if (GET_CODE (replacements->old) == SUBREG)
1672 = fixup_memory_subreg (replacements->old, insn, 0);
1675 = fixup_stack_1 (replacements->old, insn);
1677 insert_before = insn;
1679 /* If we are changing the mode, do a conversion.
1680 This might be wasteful, but combine.c will
1681 eliminate much of the waste. */
1683 if (GET_MODE (replacements->new)
1684 != GET_MODE (replacements->old))
1687 convert_move (replacements->new,
1688 replacements->old, unsignedp);
1689 seq = gen_sequence ();
1693 seq = gen_move_insn (replacements->new,
1696 emit_insn_before (seq, insert_before);
1699 replacements = replacements->next;
1703 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1704 But don't touch other insns referred to by reg-notes;
1705 we will get them elsewhere. */
1706 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
1707 if (GET_CODE (note) != INSN_LIST)
1709 = walk_fixup_memory_subreg (XEXP (note, 0), insn, 1);
1715 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1716 See if the rtx expression at *LOC in INSN needs to be changed.
1718 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1719 contain a list of original rtx's and replacements. If we find that we need
1720 to modify this insn by replacing a memory reference with a pseudo or by
1721 making a new MEM to implement a SUBREG, we consult that list to see if
1722 we have already chosen a replacement. If none has already been allocated,
1723 we allocate it and update the list. fixup_var_refs_insns will copy VAR
1724 or the SUBREG, as appropriate, to the pseudo. */
1727 fixup_var_refs_1 (var, promoted_mode, loc, insn, replacements)
1729 enum machine_mode promoted_mode;
1732 struct fixup_replacement **replacements;
1735 register rtx x = *loc;
1736 RTX_CODE code = GET_CODE (x);
1738 register rtx tem, tem1;
1739 struct fixup_replacement *replacement;
1744 if (XEXP (x, 0) == var)
1746 /* Prevent sharing of rtl that might lose. */
1747 rtx sub = copy_rtx (XEXP (var, 0));
1751 if (! validate_change (insn, loc, sub, 0))
1753 rtx y = force_operand (sub, NULL_RTX);
1755 if (! validate_change (insn, loc, y, 0))
1756 *loc = copy_to_reg (y);
1759 emit_insn_before (gen_sequence (), insn);
1767 /* If we already have a replacement, use it. Otherwise,
1768 try to fix up this address in case it is invalid. */
1770 replacement = find_fixup_replacement (replacements, var);
1771 if (replacement->new)
1773 *loc = replacement->new;
1777 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1779 /* Unless we are forcing memory to register or we changed the mode,
1780 we can leave things the way they are if the insn is valid. */
1782 INSN_CODE (insn) = -1;
1783 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1784 && recog_memoized (insn) >= 0)
1787 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1791 /* If X contains VAR, we need to unshare it here so that we update
1792 each occurrence separately. But all identical MEMs in one insn
1793 must be replaced with the same rtx because of the possibility of
1796 if (reg_mentioned_p (var, x))
1798 replacement = find_fixup_replacement (replacements, x);
1799 if (replacement->new == 0)
1800 replacement->new = copy_most_rtx (x, var);
1802 *loc = x = replacement->new;
1818 /* Note that in some cases those types of expressions are altered
1819 by optimize_bit_field, and do not survive to get here. */
1820 if (XEXP (x, 0) == var
1821 || (GET_CODE (XEXP (x, 0)) == SUBREG
1822 && SUBREG_REG (XEXP (x, 0)) == var))
1824 /* Get TEM as a valid MEM in the mode presently in the insn.
1826 We don't worry about the possibility of MATCH_DUP here; it
1827 is highly unlikely and would be tricky to handle. */
1830 if (GET_CODE (tem) == SUBREG)
1832 if (GET_MODE_BITSIZE (GET_MODE (tem))
1833 > GET_MODE_BITSIZE (GET_MODE (var)))
1835 replacement = find_fixup_replacement (replacements, var);
1836 if (replacement->new == 0)
1837 replacement->new = gen_reg_rtx (GET_MODE (var));
1838 SUBREG_REG (tem) = replacement->new;
1841 tem = fixup_memory_subreg (tem, insn, 0);
1844 tem = fixup_stack_1 (tem, insn);
1846 /* Unless we want to load from memory, get TEM into the proper mode
1847 for an extract from memory. This can only be done if the
1848 extract is at a constant position and length. */
1850 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
1851 && GET_CODE (XEXP (x, 2)) == CONST_INT
1852 && ! mode_dependent_address_p (XEXP (tem, 0))
1853 && ! MEM_VOLATILE_P (tem))
1855 enum machine_mode wanted_mode = VOIDmode;
1856 enum machine_mode is_mode = GET_MODE (tem);
1857 int pos = INTVAL (XEXP (x, 2));
1860 if (GET_CODE (x) == ZERO_EXTRACT)
1861 wanted_mode = insn_operand_mode[(int) CODE_FOR_extzv][1];
1864 if (GET_CODE (x) == SIGN_EXTRACT)
1865 wanted_mode = insn_operand_mode[(int) CODE_FOR_extv][1];
1867 /* If we have a narrower mode, we can do something. */
1868 if (wanted_mode != VOIDmode
1869 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
1871 int offset = pos / BITS_PER_UNIT;
1872 rtx old_pos = XEXP (x, 2);
1875 /* If the bytes and bits are counted differently, we
1876 must adjust the offset. */
1877 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
1878 offset = (GET_MODE_SIZE (is_mode)
1879 - GET_MODE_SIZE (wanted_mode) - offset);
1881 pos %= GET_MODE_BITSIZE (wanted_mode);
1883 newmem = gen_rtx_MEM (wanted_mode,
1884 plus_constant (XEXP (tem, 0), offset));
1885 RTX_UNCHANGING_P (newmem) = RTX_UNCHANGING_P (tem);
1886 MEM_VOLATILE_P (newmem) = MEM_VOLATILE_P (tem);
1887 MEM_IN_STRUCT_P (newmem) = MEM_IN_STRUCT_P (tem);
1889 /* Make the change and see if the insn remains valid. */
1890 INSN_CODE (insn) = -1;
1891 XEXP (x, 0) = newmem;
1892 XEXP (x, 2) = GEN_INT (pos);
1894 if (recog_memoized (insn) >= 0)
1897 /* Otherwise, restore old position. XEXP (x, 0) will be
1899 XEXP (x, 2) = old_pos;
1903 /* If we get here, the bitfield extract insn can't accept a memory
1904 reference. Copy the input into a register. */
1906 tem1 = gen_reg_rtx (GET_MODE (tem));
1907 emit_insn_before (gen_move_insn (tem1, tem), insn);
1914 if (SUBREG_REG (x) == var)
1916 /* If this is a special SUBREG made because VAR was promoted
1917 from a wider mode, replace it with VAR and call ourself
1918 recursively, this time saying that the object previously
1919 had its current mode (by virtue of the SUBREG). */
1921 if (SUBREG_PROMOTED_VAR_P (x))
1924 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements);
1928 /* If this SUBREG makes VAR wider, it has become a paradoxical
1929 SUBREG with VAR in memory, but these aren't allowed at this
1930 stage of the compilation. So load VAR into a pseudo and take
1931 a SUBREG of that pseudo. */
1932 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
1934 replacement = find_fixup_replacement (replacements, var);
1935 if (replacement->new == 0)
1936 replacement->new = gen_reg_rtx (GET_MODE (var));
1937 SUBREG_REG (x) = replacement->new;
1941 /* See if we have already found a replacement for this SUBREG.
1942 If so, use it. Otherwise, make a MEM and see if the insn
1943 is recognized. If not, or if we should force MEM into a register,
1944 make a pseudo for this SUBREG. */
1945 replacement = find_fixup_replacement (replacements, x);
1946 if (replacement->new)
1948 *loc = replacement->new;
1952 replacement->new = *loc = fixup_memory_subreg (x, insn, 0);
1954 INSN_CODE (insn) = -1;
1955 if (! flag_force_mem && recog_memoized (insn) >= 0)
1958 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
1964 /* First do special simplification of bit-field references. */
1965 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
1966 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
1967 optimize_bit_field (x, insn, 0);
1968 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
1969 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
1970 optimize_bit_field (x, insn, NULL_PTR);
1972 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
1973 into a register and then store it back out. */
1974 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
1975 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
1976 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
1977 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
1978 > GET_MODE_SIZE (GET_MODE (var))))
1980 replacement = find_fixup_replacement (replacements, var);
1981 if (replacement->new == 0)
1982 replacement->new = gen_reg_rtx (GET_MODE (var));
1984 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
1985 emit_insn_after (gen_move_insn (var, replacement->new), insn);
1988 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
1989 insn into a pseudo and store the low part of the pseudo into VAR. */
1990 if (GET_CODE (SET_DEST (x)) == SUBREG
1991 && SUBREG_REG (SET_DEST (x)) == var
1992 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
1993 > GET_MODE_SIZE (GET_MODE (var))))
1995 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
1996 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2003 rtx dest = SET_DEST (x);
2004 rtx src = SET_SRC (x);
2006 rtx outerdest = dest;
2009 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2010 || GET_CODE (dest) == SIGN_EXTRACT
2011 || GET_CODE (dest) == ZERO_EXTRACT)
2012 dest = XEXP (dest, 0);
2014 if (GET_CODE (src) == SUBREG)
2015 src = XEXP (src, 0);
2017 /* If VAR does not appear at the top level of the SET
2018 just scan the lower levels of the tree. */
2020 if (src != var && dest != var)
2023 /* We will need to rerecognize this insn. */
2024 INSN_CODE (insn) = -1;
2027 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var)
2029 /* Since this case will return, ensure we fixup all the
2031 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2032 insn, replacements);
2033 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2034 insn, replacements);
2035 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2036 insn, replacements);
2038 tem = XEXP (outerdest, 0);
2040 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2041 that may appear inside a ZERO_EXTRACT.
2042 This was legitimate when the MEM was a REG. */
2043 if (GET_CODE (tem) == SUBREG
2044 && SUBREG_REG (tem) == var)
2045 tem = fixup_memory_subreg (tem, insn, 0);
2047 tem = fixup_stack_1 (tem, insn);
2049 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2050 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2051 && ! mode_dependent_address_p (XEXP (tem, 0))
2052 && ! MEM_VOLATILE_P (tem))
2054 enum machine_mode wanted_mode
2055 = insn_operand_mode[(int) CODE_FOR_insv][0];
2056 enum machine_mode is_mode = GET_MODE (tem);
2057 int width = INTVAL (XEXP (outerdest, 1));
2058 int pos = INTVAL (XEXP (outerdest, 2));
2060 /* If we have a narrower mode, we can do something. */
2061 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2063 int offset = pos / BITS_PER_UNIT;
2064 rtx old_pos = XEXP (outerdest, 2);
2067 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2068 offset = (GET_MODE_SIZE (is_mode)
2069 - GET_MODE_SIZE (wanted_mode) - offset);
2071 pos %= GET_MODE_BITSIZE (wanted_mode);
2073 newmem = gen_rtx_MEM (wanted_mode,
2074 plus_constant (XEXP (tem, 0), offset));
2075 RTX_UNCHANGING_P (newmem) = RTX_UNCHANGING_P (tem);
2076 MEM_VOLATILE_P (newmem) = MEM_VOLATILE_P (tem);
2077 MEM_IN_STRUCT_P (newmem) = MEM_IN_STRUCT_P (tem);
2079 /* Make the change and see if the insn remains valid. */
2080 INSN_CODE (insn) = -1;
2081 XEXP (outerdest, 0) = newmem;
2082 XEXP (outerdest, 2) = GEN_INT (pos);
2084 if (recog_memoized (insn) >= 0)
2087 /* Otherwise, restore old position. XEXP (x, 0) will be
2089 XEXP (outerdest, 2) = old_pos;
2093 /* If we get here, the bit-field store doesn't allow memory
2094 or isn't located at a constant position. Load the value into
2095 a register, do the store, and put it back into memory. */
2097 tem1 = gen_reg_rtx (GET_MODE (tem));
2098 emit_insn_before (gen_move_insn (tem1, tem), insn);
2099 emit_insn_after (gen_move_insn (tem, tem1), insn);
2100 XEXP (outerdest, 0) = tem1;
2105 /* STRICT_LOW_PART is a no-op on memory references
2106 and it can cause combinations to be unrecognizable,
2109 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2110 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2112 /* A valid insn to copy VAR into or out of a register
2113 must be left alone, to avoid an infinite loop here.
2114 If the reference to VAR is by a subreg, fix that up,
2115 since SUBREG is not valid for a memref.
2116 Also fix up the address of the stack slot.
2118 Note that we must not try to recognize the insn until
2119 after we know that we have valid addresses and no
2120 (subreg (mem ...) ...) constructs, since these interfere
2121 with determining the validity of the insn. */
2123 if ((SET_SRC (x) == var
2124 || (GET_CODE (SET_SRC (x)) == SUBREG
2125 && SUBREG_REG (SET_SRC (x)) == var))
2126 && (GET_CODE (SET_DEST (x)) == REG
2127 || (GET_CODE (SET_DEST (x)) == SUBREG
2128 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2129 && GET_MODE (var) == promoted_mode
2130 && x == single_set (insn))
2134 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2135 if (replacement->new)
2136 SET_SRC (x) = replacement->new;
2137 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2138 SET_SRC (x) = replacement->new
2139 = fixup_memory_subreg (SET_SRC (x), insn, 0);
2141 SET_SRC (x) = replacement->new
2142 = fixup_stack_1 (SET_SRC (x), insn);
2144 if (recog_memoized (insn) >= 0)
2147 /* INSN is not valid, but we know that we want to
2148 copy SET_SRC (x) to SET_DEST (x) in some way. So
2149 we generate the move and see whether it requires more
2150 than one insn. If it does, we emit those insns and
2151 delete INSN. Otherwise, we an just replace the pattern
2152 of INSN; we have already verified above that INSN has
2153 no other function that to do X. */
2155 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2156 if (GET_CODE (pat) == SEQUENCE)
2158 emit_insn_after (pat, insn);
2159 PUT_CODE (insn, NOTE);
2160 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
2161 NOTE_SOURCE_FILE (insn) = 0;
2164 PATTERN (insn) = pat;
2169 if ((SET_DEST (x) == var
2170 || (GET_CODE (SET_DEST (x)) == SUBREG
2171 && SUBREG_REG (SET_DEST (x)) == var))
2172 && (GET_CODE (SET_SRC (x)) == REG
2173 || (GET_CODE (SET_SRC (x)) == SUBREG
2174 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2175 && GET_MODE (var) == promoted_mode
2176 && x == single_set (insn))
2180 if (GET_CODE (SET_DEST (x)) == SUBREG)
2181 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn, 0);
2183 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2185 if (recog_memoized (insn) >= 0)
2188 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2189 if (GET_CODE (pat) == SEQUENCE)
2191 emit_insn_after (pat, insn);
2192 PUT_CODE (insn, NOTE);
2193 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
2194 NOTE_SOURCE_FILE (insn) = 0;
2197 PATTERN (insn) = pat;
2202 /* Otherwise, storing into VAR must be handled specially
2203 by storing into a temporary and copying that into VAR
2204 with a new insn after this one. Note that this case
2205 will be used when storing into a promoted scalar since
2206 the insn will now have different modes on the input
2207 and output and hence will be invalid (except for the case
2208 of setting it to a constant, which does not need any
2209 change if it is valid). We generate extra code in that case,
2210 but combine.c will eliminate it. */
2215 rtx fixeddest = SET_DEST (x);
2217 /* STRICT_LOW_PART can be discarded, around a MEM. */
2218 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2219 fixeddest = XEXP (fixeddest, 0);
2220 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2221 if (GET_CODE (fixeddest) == SUBREG)
2223 fixeddest = fixup_memory_subreg (fixeddest, insn, 0);
2224 promoted_mode = GET_MODE (fixeddest);
2227 fixeddest = fixup_stack_1 (fixeddest, insn);
2229 temp = gen_reg_rtx (promoted_mode);
2231 emit_insn_after (gen_move_insn (fixeddest,
2232 gen_lowpart (GET_MODE (fixeddest),
2236 SET_DEST (x) = temp;
2244 /* Nothing special about this RTX; fix its operands. */
2246 fmt = GET_RTX_FORMAT (code);
2247 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2250 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements);
2254 for (j = 0; j < XVECLEN (x, i); j++)
2255 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2256 insn, replacements);
2261 /* Given X, an rtx of the form (SUBREG:m1 (MEM:m2 addr)),
2262 return an rtx (MEM:m1 newaddr) which is equivalent.
2263 If any insns must be emitted to compute NEWADDR, put them before INSN.
2265 UNCRITICAL nonzero means accept paradoxical subregs.
2266 This is used for subregs found inside REG_NOTES. */
2269 fixup_memory_subreg (x, insn, uncritical)
2274 int offset = SUBREG_WORD (x) * UNITS_PER_WORD;
2275 rtx addr = XEXP (SUBREG_REG (x), 0);
2276 enum machine_mode mode = GET_MODE (x);
2279 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2280 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))
2284 if (BYTES_BIG_ENDIAN)
2285 offset += (MIN (UNITS_PER_WORD, GET_MODE_SIZE (GET_MODE (SUBREG_REG (x))))
2286 - MIN (UNITS_PER_WORD, GET_MODE_SIZE (mode)));
2287 addr = plus_constant (addr, offset);
2288 if (!flag_force_addr && memory_address_p (mode, addr))
2289 /* Shortcut if no insns need be emitted. */
2290 return change_address (SUBREG_REG (x), mode, addr);
2292 result = change_address (SUBREG_REG (x), mode, addr);
2293 emit_insn_before (gen_sequence (), insn);
2298 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2299 Replace subexpressions of X in place.
2300 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2301 Otherwise return X, with its contents possibly altered.
2303 If any insns must be emitted to compute NEWADDR, put them before INSN.
2305 UNCRITICAL is as in fixup_memory_subreg. */
2308 walk_fixup_memory_subreg (x, insn, uncritical)
2313 register enum rtx_code code;
2320 code = GET_CODE (x);
2322 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2323 return fixup_memory_subreg (x, insn, uncritical);
2325 /* Nothing special about this RTX; fix its operands. */
2327 fmt = GET_RTX_FORMAT (code);
2328 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2331 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn, uncritical);
2335 for (j = 0; j < XVECLEN (x, i); j++)
2337 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn, uncritical);
2343 /* For each memory ref within X, if it refers to a stack slot
2344 with an out of range displacement, put the address in a temp register
2345 (emitting new insns before INSN to load these registers)
2346 and alter the memory ref to use that register.
2347 Replace each such MEM rtx with a copy, to avoid clobberage. */
2350 fixup_stack_1 (x, insn)
2355 register RTX_CODE code = GET_CODE (x);
2360 register rtx ad = XEXP (x, 0);
2361 /* If we have address of a stack slot but it's not valid
2362 (displacement is too large), compute the sum in a register. */
2363 if (GET_CODE (ad) == PLUS
2364 && GET_CODE (XEXP (ad, 0)) == REG
2365 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2366 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2367 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2368 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2369 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2371 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2372 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2373 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2374 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2377 if (memory_address_p (GET_MODE (x), ad))
2381 temp = copy_to_reg (ad);
2382 seq = gen_sequence ();
2384 emit_insn_before (seq, insn);
2385 return change_address (x, VOIDmode, temp);
2390 fmt = GET_RTX_FORMAT (code);
2391 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2394 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2398 for (j = 0; j < XVECLEN (x, i); j++)
2399 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2405 /* Optimization: a bit-field instruction whose field
2406 happens to be a byte or halfword in memory
2407 can be changed to a move instruction.
2409 We call here when INSN is an insn to examine or store into a bit-field.
2410 BODY is the SET-rtx to be altered.
2412 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2413 (Currently this is called only from function.c, and EQUIV_MEM
2417 optimize_bit_field (body, insn, equiv_mem)
2422 register rtx bitfield;
2425 enum machine_mode mode;
2427 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2428 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2429 bitfield = SET_DEST (body), destflag = 1;
2431 bitfield = SET_SRC (body), destflag = 0;
2433 /* First check that the field being stored has constant size and position
2434 and is in fact a byte or halfword suitably aligned. */
2436 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2437 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2438 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2440 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2442 register rtx memref = 0;
2444 /* Now check that the containing word is memory, not a register,
2445 and that it is safe to change the machine mode. */
2447 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2448 memref = XEXP (bitfield, 0);
2449 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2451 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2452 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2453 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2454 memref = SUBREG_REG (XEXP (bitfield, 0));
2455 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2457 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2458 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2461 && ! mode_dependent_address_p (XEXP (memref, 0))
2462 && ! MEM_VOLATILE_P (memref))
2464 /* Now adjust the address, first for any subreg'ing
2465 that we are now getting rid of,
2466 and then for which byte of the word is wanted. */
2468 register int offset = INTVAL (XEXP (bitfield, 2));
2471 /* Adjust OFFSET to count bits from low-address byte. */
2472 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2473 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2474 - offset - INTVAL (XEXP (bitfield, 1)));
2476 /* Adjust OFFSET to count bytes from low-address byte. */
2477 offset /= BITS_PER_UNIT;
2478 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2480 offset += SUBREG_WORD (XEXP (bitfield, 0)) * UNITS_PER_WORD;
2481 if (BYTES_BIG_ENDIAN)
2482 offset -= (MIN (UNITS_PER_WORD,
2483 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2484 - MIN (UNITS_PER_WORD,
2485 GET_MODE_SIZE (GET_MODE (memref))));
2489 memref = change_address (memref, mode,
2490 plus_constant (XEXP (memref, 0), offset));
2491 insns = get_insns ();
2493 emit_insns_before (insns, insn);
2495 /* Store this memory reference where
2496 we found the bit field reference. */
2500 validate_change (insn, &SET_DEST (body), memref, 1);
2501 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2503 rtx src = SET_SRC (body);
2504 while (GET_CODE (src) == SUBREG
2505 && SUBREG_WORD (src) == 0)
2506 src = SUBREG_REG (src);
2507 if (GET_MODE (src) != GET_MODE (memref))
2508 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2509 validate_change (insn, &SET_SRC (body), src, 1);
2511 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2512 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2513 /* This shouldn't happen because anything that didn't have
2514 one of these modes should have got converted explicitly
2515 and then referenced through a subreg.
2516 This is so because the original bit-field was
2517 handled by agg_mode and so its tree structure had
2518 the same mode that memref now has. */
2523 rtx dest = SET_DEST (body);
2525 while (GET_CODE (dest) == SUBREG
2526 && SUBREG_WORD (dest) == 0
2527 && (GET_MODE_CLASS (GET_MODE (dest))
2528 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest)))))
2529 dest = SUBREG_REG (dest);
2531 validate_change (insn, &SET_DEST (body), dest, 1);
2533 if (GET_MODE (dest) == GET_MODE (memref))
2534 validate_change (insn, &SET_SRC (body), memref, 1);
2537 /* Convert the mem ref to the destination mode. */
2538 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2541 convert_move (newreg, memref,
2542 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2546 validate_change (insn, &SET_SRC (body), newreg, 1);
2550 /* See if we can convert this extraction or insertion into
2551 a simple move insn. We might not be able to do so if this
2552 was, for example, part of a PARALLEL.
2554 If we succeed, write out any needed conversions. If we fail,
2555 it is hard to guess why we failed, so don't do anything
2556 special; just let the optimization be suppressed. */
2558 if (apply_change_group () && seq)
2559 emit_insns_before (seq, insn);
2564 /* These routines are responsible for converting virtual register references
2565 to the actual hard register references once RTL generation is complete.
2567 The following four variables are used for communication between the
2568 routines. They contain the offsets of the virtual registers from their
2569 respective hard registers. */
2571 static int in_arg_offset;
2572 static int var_offset;
2573 static int dynamic_offset;
2574 static int out_arg_offset;
2576 /* In most machines, the stack pointer register is equivalent to the bottom
2579 #ifndef STACK_POINTER_OFFSET
2580 #define STACK_POINTER_OFFSET 0
2583 /* If not defined, pick an appropriate default for the offset of dynamically
2584 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2585 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2587 #ifndef STACK_DYNAMIC_OFFSET
2589 #ifdef ACCUMULATE_OUTGOING_ARGS
2590 /* The bottom of the stack points to the actual arguments. If
2591 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2592 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2593 stack space for register parameters is not pushed by the caller, but
2594 rather part of the fixed stack areas and hence not included in
2595 `current_function_outgoing_args_size'. Nevertheless, we must allow
2596 for it when allocating stack dynamic objects. */
2598 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2599 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2600 (current_function_outgoing_args_size \
2601 + REG_PARM_STACK_SPACE (FNDECL) + (STACK_POINTER_OFFSET))
2604 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2605 (current_function_outgoing_args_size + (STACK_POINTER_OFFSET))
2609 #define STACK_DYNAMIC_OFFSET(FNDECL) STACK_POINTER_OFFSET
2613 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just had
2614 its address taken. DECL is the decl for the object stored in the
2615 register, for later use if we do need to force REG into the stack.
2616 REG is overwritten by the MEM like in put_reg_into_stack. */
2619 gen_mem_addressof (reg, decl)
2623 tree type = TREE_TYPE (decl);
2625 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)), REGNO (reg));
2626 SET_ADDRESSOF_DECL (r, decl);
2629 PUT_CODE (reg, MEM);
2630 PUT_MODE (reg, DECL_MODE (decl));
2631 MEM_VOLATILE_P (reg) = TREE_SIDE_EFFECTS (decl);
2632 MEM_IN_STRUCT_P (reg) = AGGREGATE_TYPE_P (type);
2634 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type));
2638 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2641 flush_addressof (decl)
2644 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2645 && DECL_RTL (decl) != 0
2646 && GET_CODE (DECL_RTL (decl)) == MEM
2647 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2648 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2649 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0));
2652 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2655 put_addressof_into_stack (r)
2658 tree decl = ADDRESSOF_DECL (r);
2659 rtx reg = XEXP (r, 0);
2661 if (GET_CODE (reg) != REG)
2664 put_reg_into_stack (0, reg, TREE_TYPE (decl), GET_MODE (reg),
2665 DECL_MODE (decl), TREE_SIDE_EFFECTS (decl),
2666 ADDRESSOF_REGNO (r));
2669 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2670 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2674 purge_addressof_1 (loc, insn, force)
2684 /* Re-start here to avoid recursion in common cases. */
2691 code = GET_CODE (x);
2693 if (code == ADDRESSOF && GET_CODE (XEXP (x, 0)) == MEM)
2696 /* We must create a copy of the rtx because it was created by
2697 overwriting a REG rtx which is always shared. */
2698 rtx sub = copy_rtx (XEXP (XEXP (x, 0), 0));
2700 if (validate_change (insn, loc, sub, 0))
2704 if (! validate_change (insn, loc,
2705 force_operand (sub, NULL_RTX),
2709 insns = get_insns ();
2711 emit_insns_before (insns, insn);
2714 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
2716 rtx sub = XEXP (XEXP (x, 0), 0);
2717 if (GET_CODE (sub) == MEM)
2718 sub = gen_rtx_MEM (GET_MODE (x), copy_rtx (XEXP (sub, 0)));
2719 if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
2721 if (! BYTES_BIG_ENDIAN && ! WORDS_BIG_ENDIAN)
2723 rtx sub2 = gen_rtx_SUBREG (GET_MODE (x), sub, 0);
2724 if (validate_change (insn, loc, sub2, 0))
2728 else if (validate_change (insn, loc, sub, 0))
2730 /* else give up and put it into the stack */
2732 else if (code == ADDRESSOF)
2734 put_addressof_into_stack (x);
2738 /* Scan all subexpressions. */
2739 fmt = GET_RTX_FORMAT (code);
2740 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
2743 purge_addressof_1 (&XEXP (x, i), insn, force);
2744 else if (*fmt == 'E')
2745 for (j = 0; j < XVECLEN (x, i); j++)
2746 purge_addressof_1 (&XVECEXP (x, i, j), insn, force);
2750 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
2751 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
2755 purge_addressof (insns)
2759 for (insn = insns; insn; insn = NEXT_INSN (insn))
2760 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
2761 || GET_CODE (insn) == CALL_INSN)
2763 purge_addressof_1 (&PATTERN (insn), insn,
2764 asm_noperands (PATTERN (insn)) > 0);
2765 purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0);
2769 /* Pass through the INSNS of function FNDECL and convert virtual register
2770 references to hard register references. */
2773 instantiate_virtual_regs (fndecl, insns)
2780 /* Compute the offsets to use for this function. */
2781 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
2782 var_offset = STARTING_FRAME_OFFSET;
2783 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
2784 out_arg_offset = STACK_POINTER_OFFSET;
2786 /* Scan all variables and parameters of this function. For each that is
2787 in memory, instantiate all virtual registers if the result is a valid
2788 address. If not, we do it later. That will handle most uses of virtual
2789 regs on many machines. */
2790 instantiate_decls (fndecl, 1);
2792 /* Initialize recognition, indicating that volatile is OK. */
2795 /* Scan through all the insns, instantiating every virtual register still
2797 for (insn = insns; insn; insn = NEXT_INSN (insn))
2798 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
2799 || GET_CODE (insn) == CALL_INSN)
2801 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
2802 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
2805 /* Instantiate the stack slots for the parm registers, for later use in
2806 addressof elimination. */
2807 for (i = 0; i < max_parm_reg; ++i)
2808 if (parm_reg_stack_loc[i])
2809 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
2811 /* Now instantiate the remaining register equivalences for debugging info.
2812 These will not be valid addresses. */
2813 instantiate_decls (fndecl, 0);
2815 /* Indicate that, from now on, assign_stack_local should use
2816 frame_pointer_rtx. */
2817 virtuals_instantiated = 1;
2820 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
2821 all virtual registers in their DECL_RTL's.
2823 If VALID_ONLY, do this only if the resulting address is still valid.
2824 Otherwise, always do it. */
2827 instantiate_decls (fndecl, valid_only)
2833 if (DECL_SAVED_INSNS (fndecl))
2834 /* When compiling an inline function, the obstack used for
2835 rtl allocation is the maybepermanent_obstack. Calling
2836 `resume_temporary_allocation' switches us back to that
2837 obstack while we process this function's parameters. */
2838 resume_temporary_allocation ();
2840 /* Process all parameters of the function. */
2841 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
2843 int size = int_size_in_bytes (TREE_TYPE (decl));
2844 instantiate_decl (DECL_RTL (decl), size, valid_only);
2846 /* If the parameter was promoted, then the incoming RTL mode may be
2847 larger than the declared type size. We must use the larger of
2849 size = MAX (GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl))), size);
2850 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
2853 /* Now process all variables defined in the function or its subblocks. */
2854 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
2856 if (DECL_INLINE (fndecl) || DECL_DEFER_OUTPUT (fndecl))
2858 /* Save all rtl allocated for this function by raising the
2859 high-water mark on the maybepermanent_obstack. */
2861 /* All further rtl allocation is now done in the current_obstack. */
2862 rtl_in_current_obstack ();
2866 /* Subroutine of instantiate_decls: Process all decls in the given
2867 BLOCK node and all its subblocks. */
2870 instantiate_decls_1 (let, valid_only)
2876 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
2877 instantiate_decl (DECL_RTL (t), int_size_in_bytes (TREE_TYPE (t)),
2880 /* Process all subblocks. */
2881 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
2882 instantiate_decls_1 (t, valid_only);
2885 /* Subroutine of the preceding procedures: Given RTL representing a
2886 decl and the size of the object, do any instantiation required.
2888 If VALID_ONLY is non-zero, it means that the RTL should only be
2889 changed if the new address is valid. */
2892 instantiate_decl (x, size, valid_only)
2897 enum machine_mode mode;
2900 /* If this is not a MEM, no need to do anything. Similarly if the
2901 address is a constant or a register that is not a virtual register. */
2903 if (x == 0 || GET_CODE (x) != MEM)
2907 if (CONSTANT_P (addr)
2908 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
2909 || (GET_CODE (addr) == REG
2910 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
2911 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
2914 /* If we should only do this if the address is valid, copy the address.
2915 We need to do this so we can undo any changes that might make the
2916 address invalid. This copy is unfortunate, but probably can't be
2920 addr = copy_rtx (addr);
2922 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
2926 /* Now verify that the resulting address is valid for every integer or
2927 floating-point mode up to and including SIZE bytes long. We do this
2928 since the object might be accessed in any mode and frame addresses
2931 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
2932 mode != VOIDmode && GET_MODE_SIZE (mode) <= size;
2933 mode = GET_MODE_WIDER_MODE (mode))
2934 if (! memory_address_p (mode, addr))
2937 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
2938 mode != VOIDmode && GET_MODE_SIZE (mode) <= size;
2939 mode = GET_MODE_WIDER_MODE (mode))
2940 if (! memory_address_p (mode, addr))
2944 /* Put back the address now that we have updated it and we either know
2945 it is valid or we don't care whether it is valid. */
2950 /* Given a pointer to a piece of rtx and an optional pointer to the
2951 containing object, instantiate any virtual registers present in it.
2953 If EXTRA_INSNS, we always do the replacement and generate
2954 any extra insns before OBJECT. If it zero, we do nothing if replacement
2957 Return 1 if we either had nothing to do or if we were able to do the
2958 needed replacement. Return 0 otherwise; we only return zero if
2959 EXTRA_INSNS is zero.
2961 We first try some simple transformations to avoid the creation of extra
2965 instantiate_virtual_regs_1 (loc, object, extra_insns)
2979 /* Re-start here to avoid recursion in common cases. */
2986 code = GET_CODE (x);
2988 /* Check for some special cases. */
3005 /* We are allowed to set the virtual registers. This means that
3006 that the actual register should receive the source minus the
3007 appropriate offset. This is used, for example, in the handling
3008 of non-local gotos. */
3009 if (SET_DEST (x) == virtual_incoming_args_rtx)
3010 new = arg_pointer_rtx, offset = - in_arg_offset;
3011 else if (SET_DEST (x) == virtual_stack_vars_rtx)
3012 new = frame_pointer_rtx, offset = - var_offset;
3013 else if (SET_DEST (x) == virtual_stack_dynamic_rtx)
3014 new = stack_pointer_rtx, offset = - dynamic_offset;
3015 else if (SET_DEST (x) == virtual_outgoing_args_rtx)
3016 new = stack_pointer_rtx, offset = - out_arg_offset;
3020 /* The only valid sources here are PLUS or REG. Just do
3021 the simplest possible thing to handle them. */
3022 if (GET_CODE (SET_SRC (x)) != REG
3023 && GET_CODE (SET_SRC (x)) != PLUS)
3027 if (GET_CODE (SET_SRC (x)) != REG)
3028 temp = force_operand (SET_SRC (x), NULL_RTX);
3031 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3035 emit_insns_before (seq, object);
3038 if (! validate_change (object, &SET_SRC (x), temp, 0)
3045 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3050 /* Handle special case of virtual register plus constant. */
3051 if (CONSTANT_P (XEXP (x, 1)))
3053 rtx old, new_offset;
3055 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3056 if (GET_CODE (XEXP (x, 0)) == PLUS)
3058 rtx inner = XEXP (XEXP (x, 0), 0);
3060 if (inner == virtual_incoming_args_rtx)
3061 new = arg_pointer_rtx, offset = in_arg_offset;
3062 else if (inner == virtual_stack_vars_rtx)
3063 new = frame_pointer_rtx, offset = var_offset;
3064 else if (inner == virtual_stack_dynamic_rtx)
3065 new = stack_pointer_rtx, offset = dynamic_offset;
3066 else if (inner == virtual_outgoing_args_rtx)
3067 new = stack_pointer_rtx, offset = out_arg_offset;
3074 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3076 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3079 else if (XEXP (x, 0) == virtual_incoming_args_rtx)
3080 new = arg_pointer_rtx, offset = in_arg_offset;
3081 else if (XEXP (x, 0) == virtual_stack_vars_rtx)
3082 new = frame_pointer_rtx, offset = var_offset;
3083 else if (XEXP (x, 0) == virtual_stack_dynamic_rtx)
3084 new = stack_pointer_rtx, offset = dynamic_offset;
3085 else if (XEXP (x, 0) == virtual_outgoing_args_rtx)
3086 new = stack_pointer_rtx, offset = out_arg_offset;
3089 /* We know the second operand is a constant. Unless the
3090 first operand is a REG (which has been already checked),
3091 it needs to be checked. */
3092 if (GET_CODE (XEXP (x, 0)) != REG)
3100 new_offset = plus_constant (XEXP (x, 1), offset);
3102 /* If the new constant is zero, try to replace the sum with just
3104 if (new_offset == const0_rtx
3105 && validate_change (object, loc, new, 0))
3108 /* Next try to replace the register and new offset.
3109 There are two changes to validate here and we can't assume that
3110 in the case of old offset equals new just changing the register
3111 will yield a valid insn. In the interests of a little efficiency,
3112 however, we only call validate change once (we don't queue up the
3113 changes and then call apply_change_group). */
3117 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3118 : (XEXP (x, 0) = new,
3119 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3127 /* Otherwise copy the new constant into a register and replace
3128 constant with that register. */
3129 temp = gen_reg_rtx (Pmode);
3131 if (validate_change (object, &XEXP (x, 1), temp, 0))
3132 emit_insn_before (gen_move_insn (temp, new_offset), object);
3135 /* If that didn't work, replace this expression with a
3136 register containing the sum. */
3139 new = gen_rtx_PLUS (Pmode, new, new_offset);
3142 temp = force_operand (new, NULL_RTX);
3146 emit_insns_before (seq, object);
3147 if (! validate_change (object, loc, temp, 0)
3148 && ! validate_replace_rtx (x, temp, object))
3156 /* Fall through to generic two-operand expression case. */
3162 case DIV: case UDIV:
3163 case MOD: case UMOD:
3164 case AND: case IOR: case XOR:
3165 case ROTATERT: case ROTATE:
3166 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3168 case GE: case GT: case GEU: case GTU:
3169 case LE: case LT: case LEU: case LTU:
3170 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3171 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3176 /* Most cases of MEM that convert to valid addresses have already been
3177 handled by our scan of decls. The only special handling we
3178 need here is to make a copy of the rtx to ensure it isn't being
3179 shared if we have to change it to a pseudo.
3181 If the rtx is a simple reference to an address via a virtual register,
3182 it can potentially be shared. In such cases, first try to make it
3183 a valid address, which can also be shared. Otherwise, copy it and
3186 First check for common cases that need no processing. These are
3187 usually due to instantiation already being done on a previous instance
3191 if (CONSTANT_ADDRESS_P (temp)
3192 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3193 || temp == arg_pointer_rtx
3195 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3196 || temp == hard_frame_pointer_rtx
3198 || temp == frame_pointer_rtx)
3201 if (GET_CODE (temp) == PLUS
3202 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3203 && (XEXP (temp, 0) == frame_pointer_rtx
3204 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3205 || XEXP (temp, 0) == hard_frame_pointer_rtx
3207 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3208 || XEXP (temp, 0) == arg_pointer_rtx
3213 if (temp == virtual_stack_vars_rtx
3214 || temp == virtual_incoming_args_rtx
3215 || (GET_CODE (temp) == PLUS
3216 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3217 && (XEXP (temp, 0) == virtual_stack_vars_rtx
3218 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
3220 /* This MEM may be shared. If the substitution can be done without
3221 the need to generate new pseudos, we want to do it in place
3222 so all copies of the shared rtx benefit. The call below will
3223 only make substitutions if the resulting address is still
3226 Note that we cannot pass X as the object in the recursive call
3227 since the insn being processed may not allow all valid
3228 addresses. However, if we were not passed on object, we can
3229 only modify X without copying it if X will have a valid
3232 ??? Also note that this can still lose if OBJECT is an insn that
3233 has less restrictions on an address that some other insn.
3234 In that case, we will modify the shared address. This case
3235 doesn't seem very likely, though. One case where this could
3236 happen is in the case of a USE or CLOBBER reference, but we
3237 take care of that below. */
3239 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
3240 object ? object : x, 0))
3243 /* Otherwise make a copy and process that copy. We copy the entire
3244 RTL expression since it might be a PLUS which could also be
3246 *loc = x = copy_rtx (x);
3249 /* Fall through to generic unary operation case. */
3251 case STRICT_LOW_PART:
3253 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
3254 case SIGN_EXTEND: case ZERO_EXTEND:
3255 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
3256 case FLOAT: case FIX:
3257 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
3261 /* These case either have just one operand or we know that we need not
3262 check the rest of the operands. */
3268 /* If the operand is a MEM, see if the change is a valid MEM. If not,
3269 go ahead and make the invalid one, but do it to a copy. For a REG,
3270 just make the recursive call, since there's no chance of a problem. */
3272 if ((GET_CODE (XEXP (x, 0)) == MEM
3273 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
3275 || (GET_CODE (XEXP (x, 0)) == REG
3276 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
3279 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
3284 /* Try to replace with a PLUS. If that doesn't work, compute the sum
3285 in front of this insn and substitute the temporary. */
3286 if (x == virtual_incoming_args_rtx)
3287 new = arg_pointer_rtx, offset = in_arg_offset;
3288 else if (x == virtual_stack_vars_rtx)
3289 new = frame_pointer_rtx, offset = var_offset;
3290 else if (x == virtual_stack_dynamic_rtx)
3291 new = stack_pointer_rtx, offset = dynamic_offset;
3292 else if (x == virtual_outgoing_args_rtx)
3293 new = stack_pointer_rtx, offset = out_arg_offset;
3297 temp = plus_constant (new, offset);
3298 if (!validate_change (object, loc, temp, 0))
3304 temp = force_operand (temp, NULL_RTX);
3308 emit_insns_before (seq, object);
3309 if (! validate_change (object, loc, temp, 0)
3310 && ! validate_replace_rtx (x, temp, object))
3318 if (GET_CODE (XEXP (x, 0)) == REG)
3321 else if (GET_CODE (XEXP (x, 0)) == MEM)
3323 /* If we have a (addressof (mem ..)), do any instantiation inside
3324 since we know we'll be making the inside valid when we finally
3325 remove the ADDRESSOF. */
3326 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
3335 /* Scan all subexpressions. */
3336 fmt = GET_RTX_FORMAT (code);
3337 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3340 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
3343 else if (*fmt == 'E')
3344 for (j = 0; j < XVECLEN (x, i); j++)
3345 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
3352 /* Optimization: assuming this function does not receive nonlocal gotos,
3353 delete the handlers for such, as well as the insns to establish
3354 and disestablish them. */
3360 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3362 /* Delete the handler by turning off the flag that would
3363 prevent jump_optimize from deleting it.
3364 Also permit deletion of the nonlocal labels themselves
3365 if nothing local refers to them. */
3366 if (GET_CODE (insn) == CODE_LABEL)
3370 LABEL_PRESERVE_P (insn) = 0;
3372 /* Remove it from the nonlocal_label list, to avoid confusing
3374 for (t = nonlocal_labels, last_t = 0; t;
3375 last_t = t, t = TREE_CHAIN (t))
3376 if (DECL_RTL (TREE_VALUE (t)) == insn)
3381 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
3383 TREE_CHAIN (last_t) = TREE_CHAIN (t);
3386 if (GET_CODE (insn) == INSN
3387 && ((nonlocal_goto_handler_slot != 0
3388 && reg_mentioned_p (nonlocal_goto_handler_slot, PATTERN (insn)))
3389 || (nonlocal_goto_stack_level != 0
3390 && reg_mentioned_p (nonlocal_goto_stack_level,
3396 /* Return a list (chain of EXPR_LIST nodes) for the nonlocal labels
3397 of the current function. */
3400 nonlocal_label_rtx_list ()
3405 for (t = nonlocal_labels; t; t = TREE_CHAIN (t))
3406 x = gen_rtx_EXPR_LIST (VOIDmode, label_rtx (TREE_VALUE (t)), x);
3411 /* Output a USE for any register use in RTL.
3412 This is used with -noreg to mark the extent of lifespan
3413 of any registers used in a user-visible variable's DECL_RTL. */
3419 if (GET_CODE (rtl) == REG)
3420 /* This is a register variable. */
3421 emit_insn (gen_rtx_USE (VOIDmode, rtl));
3422 else if (GET_CODE (rtl) == MEM
3423 && GET_CODE (XEXP (rtl, 0)) == REG
3424 && (REGNO (XEXP (rtl, 0)) < FIRST_VIRTUAL_REGISTER
3425 || REGNO (XEXP (rtl, 0)) > LAST_VIRTUAL_REGISTER)
3426 && XEXP (rtl, 0) != current_function_internal_arg_pointer)
3427 /* This is a variable-sized structure. */
3428 emit_insn (gen_rtx_USE (VOIDmode, XEXP (rtl, 0)));
3431 /* Like use_variable except that it outputs the USEs after INSN
3432 instead of at the end of the insn-chain. */
3435 use_variable_after (rtl, insn)
3438 if (GET_CODE (rtl) == REG)
3439 /* This is a register variable. */
3440 emit_insn_after (gen_rtx_USE (VOIDmode, rtl), insn);
3441 else if (GET_CODE (rtl) == MEM
3442 && GET_CODE (XEXP (rtl, 0)) == REG
3443 && (REGNO (XEXP (rtl, 0)) < FIRST_VIRTUAL_REGISTER
3444 || REGNO (XEXP (rtl, 0)) > LAST_VIRTUAL_REGISTER)
3445 && XEXP (rtl, 0) != current_function_internal_arg_pointer)
3446 /* This is a variable-sized structure. */
3447 emit_insn_after (gen_rtx_USE (VOIDmode, XEXP (rtl, 0)), insn);
3453 return max_parm_reg;
3456 /* Return the first insn following those generated by `assign_parms'. */
3459 get_first_nonparm_insn ()
3462 return NEXT_INSN (last_parm_insn);
3463 return get_insns ();
3466 /* Return the first NOTE_INSN_BLOCK_BEG note in the function.
3467 Crash if there is none. */
3470 get_first_block_beg ()
3472 register rtx searcher;
3473 register rtx insn = get_first_nonparm_insn ();
3475 for (searcher = insn; searcher; searcher = NEXT_INSN (searcher))
3476 if (GET_CODE (searcher) == NOTE
3477 && NOTE_LINE_NUMBER (searcher) == NOTE_INSN_BLOCK_BEG)
3480 abort (); /* Invalid call to this function. (See comments above.) */
3484 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
3485 This means a type for which function calls must pass an address to the
3486 function or get an address back from the function.
3487 EXP may be a type node or an expression (whose type is tested). */
3490 aggregate_value_p (exp)
3493 int i, regno, nregs;
3496 if (TREE_CODE_CLASS (TREE_CODE (exp)) == 't')
3499 type = TREE_TYPE (exp);
3501 if (RETURN_IN_MEMORY (type))
3503 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
3504 and thus can't be returned in registers. */
3505 if (TREE_ADDRESSABLE (type))
3507 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
3509 /* Make sure we have suitable call-clobbered regs to return
3510 the value in; if not, we must return it in memory. */
3511 reg = hard_function_value (type, 0);
3513 /* If we have something other than a REG (e.g. a PARALLEL), then assume
3515 if (GET_CODE (reg) != REG)
3518 regno = REGNO (reg);
3519 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
3520 for (i = 0; i < nregs; i++)
3521 if (! call_used_regs[regno + i])
3526 /* Assign RTL expressions to the function's parameters.
3527 This may involve copying them into registers and using
3528 those registers as the RTL for them.
3530 If SECOND_TIME is non-zero it means that this function is being
3531 called a second time. This is done by integrate.c when a function's
3532 compilation is deferred. We need to come back here in case the
3533 FUNCTION_ARG macro computes items needed for the rest of the compilation
3534 (such as changing which registers are fixed or caller-saved). But suppress
3535 writing any insns or setting DECL_RTL of anything in this case. */
3538 assign_parms (fndecl, second_time)
3543 register rtx entry_parm = 0;
3544 register rtx stack_parm = 0;
3545 CUMULATIVE_ARGS args_so_far;
3546 enum machine_mode promoted_mode, passed_mode;
3547 enum machine_mode nominal_mode, promoted_nominal_mode;
3549 /* Total space needed so far for args on the stack,
3550 given as a constant and a tree-expression. */
3551 struct args_size stack_args_size;
3552 tree fntype = TREE_TYPE (fndecl);
3553 tree fnargs = DECL_ARGUMENTS (fndecl);
3554 /* This is used for the arg pointer when referring to stack args. */
3555 rtx internal_arg_pointer;
3556 /* This is a dummy PARM_DECL that we used for the function result if
3557 the function returns a structure. */
3558 tree function_result_decl = 0;
3559 int varargs_setup = 0;
3560 rtx conversion_insns = 0;
3562 /* Nonzero if the last arg is named `__builtin_va_alist',
3563 which is used on some machines for old-fashioned non-ANSI varargs.h;
3564 this should be stuck onto the stack as if it had arrived there. */
3566 = (current_function_varargs
3568 && (parm = tree_last (fnargs)) != 0
3570 && (! strcmp (IDENTIFIER_POINTER (DECL_NAME (parm)),
3571 "__builtin_va_alist")));
3573 /* Nonzero if function takes extra anonymous args.
3574 This means the last named arg must be on the stack
3575 right before the anonymous ones. */
3577 = (TYPE_ARG_TYPES (fntype) != 0
3578 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
3579 != void_type_node));
3581 current_function_stdarg = stdarg;
3583 /* If the reg that the virtual arg pointer will be translated into is
3584 not a fixed reg or is the stack pointer, make a copy of the virtual
3585 arg pointer, and address parms via the copy. The frame pointer is
3586 considered fixed even though it is not marked as such.
3588 The second time through, simply use ap to avoid generating rtx. */
3590 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
3591 || ! (fixed_regs[ARG_POINTER_REGNUM]
3592 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM))
3594 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
3596 internal_arg_pointer = virtual_incoming_args_rtx;
3597 current_function_internal_arg_pointer = internal_arg_pointer;
3599 stack_args_size.constant = 0;
3600 stack_args_size.var = 0;
3602 /* If struct value address is treated as the first argument, make it so. */
3603 if (aggregate_value_p (DECL_RESULT (fndecl))
3604 && ! current_function_returns_pcc_struct
3605 && struct_value_incoming_rtx == 0)
3607 tree type = build_pointer_type (TREE_TYPE (fntype));
3609 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
3611 DECL_ARG_TYPE (function_result_decl) = type;
3612 TREE_CHAIN (function_result_decl) = fnargs;
3613 fnargs = function_result_decl;
3616 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
3617 parm_reg_stack_loc = (rtx *) savealloc (max_parm_reg * sizeof (rtx));
3618 bzero ((char *) parm_reg_stack_loc, max_parm_reg * sizeof (rtx));
3620 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
3621 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
3623 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, 0);
3626 /* We haven't yet found an argument that we must push and pretend the
3628 current_function_pretend_args_size = 0;
3630 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
3632 int aggregate = AGGREGATE_TYPE_P (TREE_TYPE (parm));
3633 struct args_size stack_offset;
3634 struct args_size arg_size;
3635 int passed_pointer = 0;
3636 int did_conversion = 0;
3637 tree passed_type = DECL_ARG_TYPE (parm);
3638 tree nominal_type = TREE_TYPE (parm);
3640 /* Set LAST_NAMED if this is last named arg before some
3642 int last_named = ((TREE_CHAIN (parm) == 0
3643 || DECL_NAME (TREE_CHAIN (parm)) == 0)
3644 && (stdarg || current_function_varargs));
3645 /* Set NAMED_ARG if this arg should be treated as a named arg. For
3646 most machines, if this is a varargs/stdarg function, then we treat
3647 the last named arg as if it were anonymous too. */
3648 #ifdef STRICT_ARGUMENT_NAMING
3651 int named_arg = ! last_named;
3654 if (TREE_TYPE (parm) == error_mark_node
3655 /* This can happen after weird syntax errors
3656 or if an enum type is defined among the parms. */
3657 || TREE_CODE (parm) != PARM_DECL
3658 || passed_type == NULL)
3660 DECL_INCOMING_RTL (parm) = DECL_RTL (parm)
3661 = gen_rtx_MEM (BLKmode, const0_rtx);
3662 TREE_USED (parm) = 1;
3666 /* For varargs.h function, save info about regs and stack space
3667 used by the individual args, not including the va_alist arg. */
3668 if (hide_last_arg && last_named)
3669 current_function_args_info = args_so_far;
3671 /* Find mode of arg as it is passed, and mode of arg
3672 as it should be during execution of this function. */
3673 passed_mode = TYPE_MODE (passed_type);
3674 nominal_mode = TYPE_MODE (nominal_type);
3676 /* If the parm's mode is VOID, its value doesn't matter,
3677 and avoid the usual things like emit_move_insn that could crash. */
3678 if (nominal_mode == VOIDmode)
3680 DECL_INCOMING_RTL (parm) = DECL_RTL (parm) = const0_rtx;
3684 /* If the parm is to be passed as a transparent union, use the
3685 type of the first field for the tests below. We have already
3686 verified that the modes are the same. */
3687 if (DECL_TRANSPARENT_UNION (parm)
3688 || TYPE_TRANSPARENT_UNION (passed_type))
3689 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
3691 /* See if this arg was passed by invisible reference. It is if
3692 it is an object whose size depends on the contents of the
3693 object itself or if the machine requires these objects be passed
3696 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
3697 && contains_placeholder_p (TYPE_SIZE (passed_type)))
3698 || TREE_ADDRESSABLE (passed_type)
3699 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3700 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
3701 passed_type, named_arg)
3705 passed_type = nominal_type = build_pointer_type (passed_type);
3707 passed_mode = nominal_mode = Pmode;
3710 promoted_mode = passed_mode;
3712 #ifdef PROMOTE_FUNCTION_ARGS
3713 /* Compute the mode in which the arg is actually extended to. */
3714 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
3717 /* Let machine desc say which reg (if any) the parm arrives in.
3718 0 means it arrives on the stack. */
3719 #ifdef FUNCTION_INCOMING_ARG
3720 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
3721 passed_type, named_arg);
3723 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
3724 passed_type, named_arg);
3727 if (entry_parm == 0)
3728 promoted_mode = passed_mode;
3730 #ifdef SETUP_INCOMING_VARARGS
3731 /* If this is the last named parameter, do any required setup for
3732 varargs or stdargs. We need to know about the case of this being an
3733 addressable type, in which case we skip the registers it
3734 would have arrived in.
3736 For stdargs, LAST_NAMED will be set for two parameters, the one that
3737 is actually the last named, and the dummy parameter. We only
3738 want to do this action once.
3740 Also, indicate when RTL generation is to be suppressed. */
3741 if (last_named && !varargs_setup)
3743 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
3744 current_function_pretend_args_size,
3750 /* Determine parm's home in the stack,
3751 in case it arrives in the stack or we should pretend it did.
3753 Compute the stack position and rtx where the argument arrives
3756 There is one complexity here: If this was a parameter that would
3757 have been passed in registers, but wasn't only because it is
3758 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
3759 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
3760 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
3761 0 as it was the previous time. */
3763 locate_and_pad_parm (promoted_mode, passed_type,
3764 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3767 #ifdef FUNCTION_INCOMING_ARG
3768 FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
3771 || varargs_setup)) != 0,
3773 FUNCTION_ARG (args_so_far, promoted_mode,
3775 named_arg || varargs_setup) != 0,
3778 fndecl, &stack_args_size, &stack_offset, &arg_size);
3782 rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
3784 if (offset_rtx == const0_rtx)
3785 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
3787 stack_parm = gen_rtx_MEM (promoted_mode,
3788 gen_rtx_PLUS (Pmode,
3789 internal_arg_pointer,
3792 /* If this is a memory ref that contains aggregate components,
3793 mark it as such for cse and loop optimize. Likewise if it
3795 MEM_IN_STRUCT_P (stack_parm) = aggregate;
3796 RTX_UNCHANGING_P (stack_parm) = TREE_READONLY (parm);
3799 /* If this parameter was passed both in registers and in the stack,
3800 use the copy on the stack. */
3801 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
3804 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3805 /* If this parm was passed part in regs and part in memory,
3806 pretend it arrived entirely in memory
3807 by pushing the register-part onto the stack.
3809 In the special case of a DImode or DFmode that is split,
3810 we could put it together in a pseudoreg directly,
3811 but for now that's not worth bothering with. */
3815 int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
3816 passed_type, named_arg);
3820 current_function_pretend_args_size
3821 = (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
3822 / (PARM_BOUNDARY / BITS_PER_UNIT)
3823 * (PARM_BOUNDARY / BITS_PER_UNIT));
3827 /* Handle calls that pass values in multiple non-contiguous
3828 locations. The Irix 6 ABI has examples of this. */
3829 if (GET_CODE (entry_parm) == PARALLEL)
3830 emit_group_store (validize_mem (stack_parm),
3833 move_block_from_reg (REGNO (entry_parm),
3834 validize_mem (stack_parm), nregs,
3835 int_size_in_bytes (TREE_TYPE (parm)));
3837 entry_parm = stack_parm;
3842 /* If we didn't decide this parm came in a register,
3843 by default it came on the stack. */
3844 if (entry_parm == 0)
3845 entry_parm = stack_parm;
3847 /* Record permanently how this parm was passed. */
3849 DECL_INCOMING_RTL (parm) = entry_parm;
3851 /* If there is actually space on the stack for this parm,
3852 count it in stack_args_size; otherwise set stack_parm to 0
3853 to indicate there is no preallocated stack slot for the parm. */
3855 if (entry_parm == stack_parm
3856 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
3857 /* On some machines, even if a parm value arrives in a register
3858 there is still an (uninitialized) stack slot allocated for it.
3860 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
3861 whether this parameter already has a stack slot allocated,
3862 because an arg block exists only if current_function_args_size
3863 is larger than some threshold, and we haven't calculated that
3864 yet. So, for now, we just assume that stack slots never exist
3866 || REG_PARM_STACK_SPACE (fndecl) > 0
3870 stack_args_size.constant += arg_size.constant;
3872 ADD_PARM_SIZE (stack_args_size, arg_size.var);
3875 /* No stack slot was pushed for this parm. */
3878 /* Update info on where next arg arrives in registers. */
3880 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
3881 passed_type, named_arg);
3883 /* If this is our second time through, we are done with this parm. */
3887 /* If we can't trust the parm stack slot to be aligned enough
3888 for its ultimate type, don't use that slot after entry.
3889 We'll make another stack slot, if we need one. */
3891 int thisparm_boundary
3892 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
3894 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
3898 /* If parm was passed in memory, and we need to convert it on entry,
3899 don't store it back in that same slot. */
3901 && nominal_mode != BLKmode && nominal_mode != passed_mode)
3905 /* Now adjust STACK_PARM to the mode and precise location
3906 where this parameter should live during execution,
3907 if we discover that it must live in the stack during execution.
3908 To make debuggers happier on big-endian machines, we store
3909 the value in the last bytes of the space available. */
3911 if (nominal_mode != BLKmode && nominal_mode != passed_mode
3916 if (BYTES_BIG_ENDIAN
3917 && GET_MODE_SIZE (nominal_mode) < UNITS_PER_WORD)
3918 stack_offset.constant += (GET_MODE_SIZE (passed_mode)
3919 - GET_MODE_SIZE (nominal_mode));
3921 offset_rtx = ARGS_SIZE_RTX (stack_offset);
3922 if (offset_rtx == const0_rtx)
3923 stack_parm = gen_rtx_MEM (nominal_mode, internal_arg_pointer);
3925 stack_parm = gen_rtx_MEM (nominal_mode,
3926 gen_rtx_PLUS (Pmode,
3927 internal_arg_pointer,
3930 /* If this is a memory ref that contains aggregate components,
3931 mark it as such for cse and loop optimize. */
3932 MEM_IN_STRUCT_P (stack_parm) = aggregate;
3937 /* We need this "use" info, because the gcc-register->stack-register
3938 converter in reg-stack.c needs to know which registers are active
3939 at the start of the function call. The actual parameter loading
3940 instructions are not always available then anymore, since they might
3941 have been optimised away. */
3943 if (GET_CODE (entry_parm) == REG && !(hide_last_arg && last_named))
3944 emit_insn (gen_rtx_USE (GET_MODE (entry_parm), entry_parm));
3947 /* ENTRY_PARM is an RTX for the parameter as it arrives,
3948 in the mode in which it arrives.
3949 STACK_PARM is an RTX for a stack slot where the parameter can live
3950 during the function (in case we want to put it there).
3951 STACK_PARM is 0 if no stack slot was pushed for it.
3953 Now output code if necessary to convert ENTRY_PARM to
3954 the type in which this function declares it,
3955 and store that result in an appropriate place,
3956 which may be a pseudo reg, may be STACK_PARM,
3957 or may be a local stack slot if STACK_PARM is 0.
3959 Set DECL_RTL to that place. */
3961 if (nominal_mode == BLKmode || GET_CODE (entry_parm) == PARALLEL)
3963 /* If a BLKmode arrives in registers, copy it to a stack slot.
3964 Handle calls that pass values in multiple non-contiguous
3965 locations. The Irix 6 ABI has examples of this. */
3966 if (GET_CODE (entry_parm) == REG
3967 || GET_CODE (entry_parm) == PARALLEL)
3970 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
3973 /* Note that we will be storing an integral number of words.
3974 So we have to be careful to ensure that we allocate an
3975 integral number of words. We do this below in the
3976 assign_stack_local if space was not allocated in the argument
3977 list. If it was, this will not work if PARM_BOUNDARY is not
3978 a multiple of BITS_PER_WORD. It isn't clear how to fix this
3979 if it becomes a problem. */
3981 if (stack_parm == 0)
3984 = assign_stack_local (GET_MODE (entry_parm),
3987 /* If this is a memory ref that contains aggregate
3988 components, mark it as such for cse and loop optimize. */
3989 MEM_IN_STRUCT_P (stack_parm) = aggregate;
3992 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
3995 if (TREE_READONLY (parm))
3996 RTX_UNCHANGING_P (stack_parm) = 1;
3998 /* Handle calls that pass values in multiple non-contiguous
3999 locations. The Irix 6 ABI has examples of this. */
4000 if (GET_CODE (entry_parm) == PARALLEL)
4001 emit_group_store (validize_mem (stack_parm), entry_parm);
4003 move_block_from_reg (REGNO (entry_parm),
4004 validize_mem (stack_parm),
4005 size_stored / UNITS_PER_WORD,
4006 int_size_in_bytes (TREE_TYPE (parm)));
4008 DECL_RTL (parm) = stack_parm;
4010 else if (! ((obey_regdecls && ! DECL_REGISTER (parm)
4011 && ! DECL_INLINE (fndecl))
4012 /* layout_decl may set this. */
4013 || TREE_ADDRESSABLE (parm)
4014 || TREE_SIDE_EFFECTS (parm)
4015 /* If -ffloat-store specified, don't put explicit
4016 float variables into registers. */
4017 || (flag_float_store
4018 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4019 /* Always assign pseudo to structure return or item passed
4020 by invisible reference. */
4021 || passed_pointer || parm == function_result_decl)
4023 /* Store the parm in a pseudoregister during the function, but we
4024 may need to do it in a wider mode. */
4026 register rtx parmreg;
4027 int regno, regnoi, regnor;
4029 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4031 promoted_nominal_mode
4032 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4034 parmreg = gen_reg_rtx (promoted_nominal_mode);
4035 mark_user_reg (parmreg);
4037 /* If this was an item that we received a pointer to, set DECL_RTL
4042 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)), parmreg);
4043 MEM_IN_STRUCT_P (DECL_RTL (parm)) = aggregate;
4046 DECL_RTL (parm) = parmreg;
4048 /* Copy the value into the register. */
4049 if (nominal_mode != passed_mode
4050 || promoted_nominal_mode != promoted_mode)
4052 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4053 mode, by the caller. We now have to convert it to
4054 NOMINAL_MODE, if different. However, PARMREG may be in
4055 a different mode than NOMINAL_MODE if it is being stored
4058 If ENTRY_PARM is a hard register, it might be in a register
4059 not valid for operating in its mode (e.g., an odd-numbered
4060 register for a DFmode). In that case, moves are the only
4061 thing valid, so we can't do a convert from there. This
4062 occurs when the calling sequence allow such misaligned
4065 In addition, the conversion may involve a call, which could
4066 clobber parameters which haven't been copied to pseudo
4067 registers yet. Therefore, we must first copy the parm to
4068 a pseudo reg here, and save the conversion until after all
4069 parameters have been moved. */
4071 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4073 emit_move_insn (tempreg, validize_mem (entry_parm));
4075 push_to_sequence (conversion_insns);
4076 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4078 expand_assignment (parm,
4079 make_tree (nominal_type, tempreg), 0, 0);
4080 conversion_insns = get_insns ();
4085 emit_move_insn (parmreg, validize_mem (entry_parm));
4087 /* If we were passed a pointer but the actual value
4088 can safely live in a register, put it in one. */
4089 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4090 && ! ((obey_regdecls && ! DECL_REGISTER (parm)
4091 && ! DECL_INLINE (fndecl))
4092 /* layout_decl may set this. */
4093 || TREE_ADDRESSABLE (parm)
4094 || TREE_SIDE_EFFECTS (parm)
4095 /* If -ffloat-store specified, don't put explicit
4096 float variables into registers. */
4097 || (flag_float_store
4098 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE)))
4100 /* We can't use nominal_mode, because it will have been set to
4101 Pmode above. We must use the actual mode of the parm. */
4102 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4103 mark_user_reg (parmreg);
4104 emit_move_insn (parmreg, DECL_RTL (parm));
4105 DECL_RTL (parm) = parmreg;
4106 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4110 #ifdef FUNCTION_ARG_CALLEE_COPIES
4111 /* If we are passed an arg by reference and it is our responsibility
4112 to make a copy, do it now.
4113 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4114 original argument, so we must recreate them in the call to
4115 FUNCTION_ARG_CALLEE_COPIES. */
4116 /* ??? Later add code to handle the case that if the argument isn't
4117 modified, don't do the copy. */
4119 else if (passed_pointer
4120 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4121 TYPE_MODE (DECL_ARG_TYPE (parm)),
4122 DECL_ARG_TYPE (parm),
4124 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4127 tree type = DECL_ARG_TYPE (parm);
4129 /* This sequence may involve a library call perhaps clobbering
4130 registers that haven't been copied to pseudos yet. */
4132 push_to_sequence (conversion_insns);
4134 if (TYPE_SIZE (type) == 0
4135 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4136 /* This is a variable sized object. */
4137 copy = gen_rtx_MEM (BLKmode,
4138 allocate_dynamic_stack_space
4139 (expr_size (parm), NULL_RTX,
4140 TYPE_ALIGN (type)));
4142 copy = assign_stack_temp (TYPE_MODE (type),
4143 int_size_in_bytes (type), 1);
4144 MEM_IN_STRUCT_P (copy) = AGGREGATE_TYPE_P (type);
4145 RTX_UNCHANGING_P (copy) = TREE_READONLY (parm);
4147 store_expr (parm, copy, 0);
4148 emit_move_insn (parmreg, XEXP (copy, 0));
4149 if (flag_check_memory_usage)
4150 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
4151 XEXP (copy, 0), ptr_mode,
4152 GEN_INT (int_size_in_bytes (type)),
4153 TYPE_MODE (sizetype),
4154 GEN_INT (MEMORY_USE_RW),
4155 TYPE_MODE (integer_type_node));
4156 conversion_insns = get_insns ();
4160 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4162 /* In any case, record the parm's desired stack location
4163 in case we later discover it must live in the stack.
4165 If it is a COMPLEX value, store the stack location for both
4168 if (GET_CODE (parmreg) == CONCAT)
4169 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4171 regno = REGNO (parmreg);
4173 if (regno >= max_parm_reg)
4176 int old_max_parm_reg = max_parm_reg;
4178 /* It's slow to expand this one register at a time,
4179 but it's also rare and we need max_parm_reg to be
4180 precisely correct. */
4181 max_parm_reg = regno + 1;
4182 new = (rtx *) savealloc (max_parm_reg * sizeof (rtx));
4183 bcopy ((char *) parm_reg_stack_loc, (char *) new,
4184 old_max_parm_reg * sizeof (rtx));
4185 bzero ((char *) (new + old_max_parm_reg),
4186 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4187 parm_reg_stack_loc = new;
4190 if (GET_CODE (parmreg) == CONCAT)
4192 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
4194 regnor = REGNO (gen_realpart (submode, parmreg));
4195 regnoi = REGNO (gen_imagpart (submode, parmreg));
4197 if (stack_parm != 0)
4199 parm_reg_stack_loc[regnor]
4200 = gen_realpart (submode, stack_parm);
4201 parm_reg_stack_loc[regnoi]
4202 = gen_imagpart (submode, stack_parm);
4206 parm_reg_stack_loc[regnor] = 0;
4207 parm_reg_stack_loc[regnoi] = 0;
4211 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
4213 /* Mark the register as eliminable if we did no conversion
4214 and it was copied from memory at a fixed offset,
4215 and the arg pointer was not copied to a pseudo-reg.
4216 If the arg pointer is a pseudo reg or the offset formed
4217 an invalid address, such memory-equivalences
4218 as we make here would screw up life analysis for it. */
4219 if (nominal_mode == passed_mode
4222 && GET_CODE (stack_parm) == MEM
4223 && stack_offset.var == 0
4224 && reg_mentioned_p (virtual_incoming_args_rtx,
4225 XEXP (stack_parm, 0)))
4227 rtx linsn = get_last_insn ();
4230 /* Mark complex types separately. */
4231 if (GET_CODE (parmreg) == CONCAT)
4232 /* Scan backwards for the set of the real and
4234 for (sinsn = linsn; sinsn != 0;
4235 sinsn = prev_nonnote_insn (sinsn))
4237 set = single_set (sinsn);
4239 && SET_DEST (set) == regno_reg_rtx [regnoi])
4241 = gen_rtx_EXPR_LIST (REG_EQUIV,
4242 parm_reg_stack_loc[regnoi],
4245 && SET_DEST (set) == regno_reg_rtx [regnor])
4247 = gen_rtx_EXPR_LIST (REG_EQUIV,
4248 parm_reg_stack_loc[regnor],
4251 else if ((set = single_set (linsn)) != 0
4252 && SET_DEST (set) == parmreg)
4254 = gen_rtx_EXPR_LIST (REG_EQUIV,
4255 stack_parm, REG_NOTES (linsn));
4258 /* For pointer data type, suggest pointer register. */
4259 if (TREE_CODE (TREE_TYPE (parm)) == POINTER_TYPE)
4260 mark_reg_pointer (parmreg,
4261 (TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm)))
4266 /* Value must be stored in the stack slot STACK_PARM
4267 during function execution. */
4269 if (promoted_mode != nominal_mode)
4271 /* Conversion is required. */
4272 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4274 emit_move_insn (tempreg, validize_mem (entry_parm));
4276 push_to_sequence (conversion_insns);
4277 entry_parm = convert_to_mode (nominal_mode, tempreg,
4278 TREE_UNSIGNED (TREE_TYPE (parm)));
4281 /* ??? This may need a big-endian conversion on sparc64. */
4282 stack_parm = change_address (stack_parm, nominal_mode,
4285 conversion_insns = get_insns ();
4290 if (entry_parm != stack_parm)
4292 if (stack_parm == 0)
4295 = assign_stack_local (GET_MODE (entry_parm),
4296 GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
4297 /* If this is a memory ref that contains aggregate components,
4298 mark it as such for cse and loop optimize. */
4299 MEM_IN_STRUCT_P (stack_parm) = aggregate;
4302 if (promoted_mode != nominal_mode)
4304 push_to_sequence (conversion_insns);
4305 emit_move_insn (validize_mem (stack_parm),
4306 validize_mem (entry_parm));
4307 conversion_insns = get_insns ();
4311 emit_move_insn (validize_mem (stack_parm),
4312 validize_mem (entry_parm));
4314 if (flag_check_memory_usage
4315 && entry_parm != stack_parm
4316 && promoted_mode != nominal_mode)
4318 push_to_sequence (conversion_insns);
4319 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
4320 XEXP (stack_parm, 0), ptr_mode,
4321 GEN_INT (GET_MODE_SIZE (GET_MODE
4323 TYPE_MODE (sizetype),
4324 GEN_INT (MEMORY_USE_RW),
4325 TYPE_MODE (integer_type_node));
4327 conversion_insns = get_insns ();
4330 DECL_RTL (parm) = stack_parm;
4333 /* If this "parameter" was the place where we are receiving the
4334 function's incoming structure pointer, set up the result. */
4335 if (parm == function_result_decl)
4337 tree result = DECL_RESULT (fndecl);
4338 tree restype = TREE_TYPE (result);
4341 = gen_rtx_MEM (DECL_MODE (result), DECL_RTL (parm));
4343 MEM_IN_STRUCT_P (DECL_RTL (result)) = AGGREGATE_TYPE_P (restype);
4346 if (TREE_THIS_VOLATILE (parm))
4347 MEM_VOLATILE_P (DECL_RTL (parm)) = 1;
4348 if (TREE_READONLY (parm))
4349 RTX_UNCHANGING_P (DECL_RTL (parm)) = 1;
4352 /* Output all parameter conversion instructions (possibly including calls)
4353 now that all parameters have been copied out of hard registers. */
4354 emit_insns (conversion_insns);
4356 last_parm_insn = get_last_insn ();
4358 current_function_args_size = stack_args_size.constant;
4360 /* Adjust function incoming argument size for alignment and
4363 #ifdef REG_PARM_STACK_SPACE
4364 #ifndef MAYBE_REG_PARM_STACK_SPACE
4365 current_function_args_size = MAX (current_function_args_size,
4366 REG_PARM_STACK_SPACE (fndecl));
4370 #ifdef STACK_BOUNDARY
4371 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
4373 current_function_args_size
4374 = ((current_function_args_size + STACK_BYTES - 1)
4375 / STACK_BYTES) * STACK_BYTES;
4378 #ifdef ARGS_GROW_DOWNWARD
4379 current_function_arg_offset_rtx
4380 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
4381 : expand_expr (size_binop (MINUS_EXPR, stack_args_size.var,
4382 size_int (-stack_args_size.constant)),
4383 NULL_RTX, VOIDmode, EXPAND_MEMORY_USE_BAD));
4385 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
4388 /* See how many bytes, if any, of its args a function should try to pop
4391 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
4392 current_function_args_size);
4394 /* For stdarg.h function, save info about
4395 regs and stack space used by the named args. */
4398 current_function_args_info = args_so_far;
4400 /* Set the rtx used for the function return value. Put this in its
4401 own variable so any optimizers that need this information don't have
4402 to include tree.h. Do this here so it gets done when an inlined
4403 function gets output. */
4405 current_function_return_rtx = DECL_RTL (DECL_RESULT (fndecl));
4408 /* Indicate whether REGNO is an incoming argument to the current function
4409 that was promoted to a wider mode. If so, return the RTX for the
4410 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
4411 that REGNO is promoted from and whether the promotion was signed or
4414 #ifdef PROMOTE_FUNCTION_ARGS
4417 promoted_input_arg (regno, pmode, punsignedp)
4419 enum machine_mode *pmode;
4424 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
4425 arg = TREE_CHAIN (arg))
4426 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
4427 && REGNO (DECL_INCOMING_RTL (arg)) == regno
4428 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
4430 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
4431 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
4433 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
4434 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
4435 && mode != DECL_MODE (arg))
4437 *pmode = DECL_MODE (arg);
4438 *punsignedp = unsignedp;
4439 return DECL_INCOMING_RTL (arg);
4448 /* Compute the size and offset from the start of the stacked arguments for a
4449 parm passed in mode PASSED_MODE and with type TYPE.
4451 INITIAL_OFFSET_PTR points to the current offset into the stacked
4454 The starting offset and size for this parm are returned in *OFFSET_PTR
4455 and *ARG_SIZE_PTR, respectively.
4457 IN_REGS is non-zero if the argument will be passed in registers. It will
4458 never be set if REG_PARM_STACK_SPACE is not defined.
4460 FNDECL is the function in which the argument was defined.
4462 There are two types of rounding that are done. The first, controlled by
4463 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
4464 list to be aligned to the specific boundary (in bits). This rounding
4465 affects the initial and starting offsets, but not the argument size.
4467 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
4468 optionally rounds the size of the parm to PARM_BOUNDARY. The
4469 initial offset is not affected by this rounding, while the size always
4470 is and the starting offset may be. */
4472 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
4473 initial_offset_ptr is positive because locate_and_pad_parm's
4474 callers pass in the total size of args so far as
4475 initial_offset_ptr. arg_size_ptr is always positive.*/
4478 locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
4479 initial_offset_ptr, offset_ptr, arg_size_ptr)
4480 enum machine_mode passed_mode;
4484 struct args_size *initial_offset_ptr;
4485 struct args_size *offset_ptr;
4486 struct args_size *arg_size_ptr;
4489 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
4490 enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
4491 int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
4493 #ifdef REG_PARM_STACK_SPACE
4494 /* If we have found a stack parm before we reach the end of the
4495 area reserved for registers, skip that area. */
4498 int reg_parm_stack_space = 0;
4500 #ifdef MAYBE_REG_PARM_STACK_SPACE
4501 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
4503 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
4505 if (reg_parm_stack_space > 0)
4507 if (initial_offset_ptr->var)
4509 initial_offset_ptr->var
4510 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
4511 size_int (reg_parm_stack_space));
4512 initial_offset_ptr->constant = 0;
4514 else if (initial_offset_ptr->constant < reg_parm_stack_space)
4515 initial_offset_ptr->constant = reg_parm_stack_space;
4518 #endif /* REG_PARM_STACK_SPACE */
4520 arg_size_ptr->var = 0;
4521 arg_size_ptr->constant = 0;
4523 #ifdef ARGS_GROW_DOWNWARD
4524 if (initial_offset_ptr->var)
4526 offset_ptr->constant = 0;
4527 offset_ptr->var = size_binop (MINUS_EXPR, integer_zero_node,
4528 initial_offset_ptr->var);
4532 offset_ptr->constant = - initial_offset_ptr->constant;
4533 offset_ptr->var = 0;
4535 if (where_pad != none
4536 && (TREE_CODE (sizetree) != INTEGER_CST
4537 || ((TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)))
4538 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
4539 SUB_PARM_SIZE (*offset_ptr, sizetree);
4540 if (where_pad != downward)
4541 pad_to_arg_alignment (offset_ptr, boundary);
4542 if (initial_offset_ptr->var)
4544 arg_size_ptr->var = size_binop (MINUS_EXPR,
4545 size_binop (MINUS_EXPR,
4547 initial_offset_ptr->var),
4552 arg_size_ptr->constant = (- initial_offset_ptr->constant
4553 - offset_ptr->constant);
4555 #else /* !ARGS_GROW_DOWNWARD */
4556 pad_to_arg_alignment (initial_offset_ptr, boundary);
4557 *offset_ptr = *initial_offset_ptr;
4559 #ifdef PUSH_ROUNDING
4560 if (passed_mode != BLKmode)
4561 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
4564 /* Pad_below needs the pre-rounded size to know how much to pad below
4565 so this must be done before rounding up. */
4566 if (where_pad == downward
4567 /* However, BLKmode args passed in regs have their padding done elsewhere.
4568 The stack slot must be able to hold the entire register. */
4569 && !(in_regs && passed_mode == BLKmode))
4570 pad_below (offset_ptr, passed_mode, sizetree);
4572 if (where_pad != none
4573 && (TREE_CODE (sizetree) != INTEGER_CST
4574 || ((TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)))
4575 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
4577 ADD_PARM_SIZE (*arg_size_ptr, sizetree);
4578 #endif /* ARGS_GROW_DOWNWARD */
4581 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
4582 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
4585 pad_to_arg_alignment (offset_ptr, boundary)
4586 struct args_size *offset_ptr;
4589 int boundary_in_bytes = boundary / BITS_PER_UNIT;
4591 if (boundary > BITS_PER_UNIT)
4593 if (offset_ptr->var)
4596 #ifdef ARGS_GROW_DOWNWARD
4601 (ARGS_SIZE_TREE (*offset_ptr),
4602 boundary / BITS_PER_UNIT);
4603 offset_ptr->constant = 0; /*?*/
4606 offset_ptr->constant =
4607 #ifdef ARGS_GROW_DOWNWARD
4608 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
4610 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
4615 #ifndef ARGS_GROW_DOWNWARD
4617 pad_below (offset_ptr, passed_mode, sizetree)
4618 struct args_size *offset_ptr;
4619 enum machine_mode passed_mode;
4622 if (passed_mode != BLKmode)
4624 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
4625 offset_ptr->constant
4626 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
4627 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
4628 - GET_MODE_SIZE (passed_mode));
4632 if (TREE_CODE (sizetree) != INTEGER_CST
4633 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
4635 /* Round the size up to multiple of PARM_BOUNDARY bits. */
4636 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
4638 ADD_PARM_SIZE (*offset_ptr, s2);
4639 SUB_PARM_SIZE (*offset_ptr, sizetree);
4646 round_down (value, divisor)
4650 return size_binop (MULT_EXPR,
4651 size_binop (FLOOR_DIV_EXPR, value, size_int (divisor)),
4652 size_int (divisor));
4655 /* Walk the tree of blocks describing the binding levels within a function
4656 and warn about uninitialized variables.
4657 This is done after calling flow_analysis and before global_alloc
4658 clobbers the pseudo-regs to hard regs. */
4661 uninitialized_vars_warning (block)
4664 register tree decl, sub;
4665 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
4667 if (TREE_CODE (decl) == VAR_DECL
4668 /* These warnings are unreliable for and aggregates
4669 because assigning the fields one by one can fail to convince
4670 flow.c that the entire aggregate was initialized.
4671 Unions are troublesome because members may be shorter. */
4672 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
4673 && DECL_RTL (decl) != 0
4674 && GET_CODE (DECL_RTL (decl)) == REG
4675 && regno_uninitialized (REGNO (DECL_RTL (decl))))
4676 warning_with_decl (decl,
4677 "`%s' might be used uninitialized in this function");
4678 if (TREE_CODE (decl) == VAR_DECL
4679 && DECL_RTL (decl) != 0
4680 && GET_CODE (DECL_RTL (decl)) == REG
4681 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
4682 warning_with_decl (decl,
4683 "variable `%s' might be clobbered by `longjmp' or `vfork'");
4685 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
4686 uninitialized_vars_warning (sub);
4689 /* Do the appropriate part of uninitialized_vars_warning
4690 but for arguments instead of local variables. */
4693 setjmp_args_warning ()
4696 for (decl = DECL_ARGUMENTS (current_function_decl);
4697 decl; decl = TREE_CHAIN (decl))
4698 if (DECL_RTL (decl) != 0
4699 && GET_CODE (DECL_RTL (decl)) == REG
4700 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
4701 warning_with_decl (decl, "argument `%s' might be clobbered by `longjmp' or `vfork'");
4704 /* If this function call setjmp, put all vars into the stack
4705 unless they were declared `register'. */
4708 setjmp_protect (block)
4711 register tree decl, sub;
4712 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
4713 if ((TREE_CODE (decl) == VAR_DECL
4714 || TREE_CODE (decl) == PARM_DECL)
4715 && DECL_RTL (decl) != 0
4716 && (GET_CODE (DECL_RTL (decl)) == REG
4717 || (GET_CODE (DECL_RTL (decl)) == MEM
4718 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
4719 /* If this variable came from an inline function, it must be
4720 that it's life doesn't overlap the setjmp. If there was a
4721 setjmp in the function, it would already be in memory. We
4722 must exclude such variable because their DECL_RTL might be
4723 set to strange things such as virtual_stack_vars_rtx. */
4724 && ! DECL_FROM_INLINE (decl)
4726 #ifdef NON_SAVING_SETJMP
4727 /* If longjmp doesn't restore the registers,
4728 don't put anything in them. */
4732 ! DECL_REGISTER (decl)))
4733 put_var_into_stack (decl);
4734 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
4735 setjmp_protect (sub);
4738 /* Like the previous function, but for args instead of local variables. */
4741 setjmp_protect_args ()
4744 for (decl = DECL_ARGUMENTS (current_function_decl);
4745 decl; decl = TREE_CHAIN (decl))
4746 if ((TREE_CODE (decl) == VAR_DECL
4747 || TREE_CODE (decl) == PARM_DECL)
4748 && DECL_RTL (decl) != 0
4749 && (GET_CODE (DECL_RTL (decl)) == REG
4750 || (GET_CODE (DECL_RTL (decl)) == MEM
4751 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
4753 /* If longjmp doesn't restore the registers,
4754 don't put anything in them. */
4755 #ifdef NON_SAVING_SETJMP
4759 ! DECL_REGISTER (decl)))
4760 put_var_into_stack (decl);
4763 /* Return the context-pointer register corresponding to DECL,
4764 or 0 if it does not need one. */
4767 lookup_static_chain (decl)
4770 tree context = decl_function_context (decl);
4774 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
4777 /* We treat inline_function_decl as an alias for the current function
4778 because that is the inline function whose vars, types, etc.
4779 are being merged into the current function.
4780 See expand_inline_function. */
4781 if (context == current_function_decl || context == inline_function_decl)
4782 return virtual_stack_vars_rtx;
4784 for (link = context_display; link; link = TREE_CHAIN (link))
4785 if (TREE_PURPOSE (link) == context)
4786 return RTL_EXPR_RTL (TREE_VALUE (link));
4791 /* Convert a stack slot address ADDR for variable VAR
4792 (from a containing function)
4793 into an address valid in this function (using a static chain). */
4796 fix_lexical_addr (addr, var)
4802 tree context = decl_function_context (var);
4803 struct function *fp;
4806 /* If this is the present function, we need not do anything. */
4807 if (context == current_function_decl || context == inline_function_decl)
4810 for (fp = outer_function_chain; fp; fp = fp->next)
4811 if (fp->decl == context)
4817 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
4818 addr = XEXP (XEXP (addr, 0), 0);
4820 /* Decode given address as base reg plus displacement. */
4821 if (GET_CODE (addr) == REG)
4822 basereg = addr, displacement = 0;
4823 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
4824 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
4828 /* We accept vars reached via the containing function's
4829 incoming arg pointer and via its stack variables pointer. */
4830 if (basereg == fp->internal_arg_pointer)
4832 /* If reached via arg pointer, get the arg pointer value
4833 out of that function's stack frame.
4835 There are two cases: If a separate ap is needed, allocate a
4836 slot in the outer function for it and dereference it that way.
4837 This is correct even if the real ap is actually a pseudo.
4838 Otherwise, just adjust the offset from the frame pointer to
4841 #ifdef NEED_SEPARATE_AP
4844 if (fp->arg_pointer_save_area == 0)
4845 fp->arg_pointer_save_area
4846 = assign_outer_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0, fp);
4848 addr = fix_lexical_addr (XEXP (fp->arg_pointer_save_area, 0), var);
4849 addr = memory_address (Pmode, addr);
4851 base = copy_to_reg (gen_rtx_MEM (Pmode, addr));
4853 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
4854 base = lookup_static_chain (var);
4858 else if (basereg == virtual_stack_vars_rtx)
4860 /* This is the same code as lookup_static_chain, duplicated here to
4861 avoid an extra call to decl_function_context. */
4864 for (link = context_display; link; link = TREE_CHAIN (link))
4865 if (TREE_PURPOSE (link) == context)
4867 base = RTL_EXPR_RTL (TREE_VALUE (link));
4875 /* Use same offset, relative to appropriate static chain or argument
4877 return plus_constant (base, displacement);
4880 /* Return the address of the trampoline for entering nested fn FUNCTION.
4881 If necessary, allocate a trampoline (in the stack frame)
4882 and emit rtl to initialize its contents (at entry to this function). */
4885 trampoline_address (function)
4891 struct function *fp;
4894 /* Find an existing trampoline and return it. */
4895 for (link = trampoline_list; link; link = TREE_CHAIN (link))
4896 if (TREE_PURPOSE (link) == function)
4898 round_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
4900 for (fp = outer_function_chain; fp; fp = fp->next)
4901 for (link = fp->trampoline_list; link; link = TREE_CHAIN (link))
4902 if (TREE_PURPOSE (link) == function)
4904 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
4906 return round_trampoline_addr (tramp);
4909 /* None exists; we must make one. */
4911 /* Find the `struct function' for the function containing FUNCTION. */
4913 fn_context = decl_function_context (function);
4914 if (fn_context != current_function_decl
4915 && fn_context != inline_function_decl)
4916 for (fp = outer_function_chain; fp; fp = fp->next)
4917 if (fp->decl == fn_context)
4920 /* Allocate run-time space for this trampoline
4921 (usually in the defining function's stack frame). */
4922 #ifdef ALLOCATE_TRAMPOLINE
4923 tramp = ALLOCATE_TRAMPOLINE (fp);
4925 /* If rounding needed, allocate extra space
4926 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
4927 #ifdef TRAMPOLINE_ALIGNMENT
4928 #define TRAMPOLINE_REAL_SIZE \
4929 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
4931 #define TRAMPOLINE_REAL_SIZE (TRAMPOLINE_SIZE)
4934 tramp = assign_outer_stack_local (BLKmode, TRAMPOLINE_REAL_SIZE, 0, fp);
4936 tramp = assign_stack_local (BLKmode, TRAMPOLINE_REAL_SIZE, 0);
4939 /* Record the trampoline for reuse and note it for later initialization
4940 by expand_function_end. */
4943 push_obstacks (fp->function_maybepermanent_obstack,
4944 fp->function_maybepermanent_obstack);
4945 rtlexp = make_node (RTL_EXPR);
4946 RTL_EXPR_RTL (rtlexp) = tramp;
4947 fp->trampoline_list = tree_cons (function, rtlexp, fp->trampoline_list);
4952 /* Make the RTL_EXPR node temporary, not momentary, so that the
4953 trampoline_list doesn't become garbage. */
4954 int momentary = suspend_momentary ();
4955 rtlexp = make_node (RTL_EXPR);
4956 resume_momentary (momentary);
4958 RTL_EXPR_RTL (rtlexp) = tramp;
4959 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
4962 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
4963 return round_trampoline_addr (tramp);
4966 /* Given a trampoline address,
4967 round it to multiple of TRAMPOLINE_ALIGNMENT. */
4970 round_trampoline_addr (tramp)
4973 #ifdef TRAMPOLINE_ALIGNMENT
4974 /* Round address up to desired boundary. */
4975 rtx temp = gen_reg_rtx (Pmode);
4976 temp = expand_binop (Pmode, add_optab, tramp,
4977 GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1),
4978 temp, 0, OPTAB_LIB_WIDEN);
4979 tramp = expand_binop (Pmode, and_optab, temp,
4980 GEN_INT (- TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT),
4981 temp, 0, OPTAB_LIB_WIDEN);
4986 /* The functions identify_blocks and reorder_blocks provide a way to
4987 reorder the tree of BLOCK nodes, for optimizers that reshuffle or
4988 duplicate portions of the RTL code. Call identify_blocks before
4989 changing the RTL, and call reorder_blocks after. */
4991 /* Put all this function's BLOCK nodes including those that are chained
4992 onto the first block into a vector, and return it.
4993 Also store in each NOTE for the beginning or end of a block
4994 the index of that block in the vector.
4995 The arguments are BLOCK, the chain of top-level blocks of the function,
4996 and INSNS, the insn chain of the function. */
4999 identify_blocks (block, insns)
5007 int next_block_number = 1;
5008 int current_block_number = 1;
5014 n_blocks = all_blocks (block, 0);
5015 block_vector = (tree *) xmalloc (n_blocks * sizeof (tree));
5016 block_stack = (int *) alloca (n_blocks * sizeof (int));
5018 all_blocks (block, block_vector);
5020 for (insn = insns; insn; insn = NEXT_INSN (insn))
5021 if (GET_CODE (insn) == NOTE)
5023 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5025 block_stack[depth++] = current_block_number;
5026 current_block_number = next_block_number;
5027 NOTE_BLOCK_NUMBER (insn) = next_block_number++;
5029 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5031 current_block_number = block_stack[--depth];
5032 NOTE_BLOCK_NUMBER (insn) = current_block_number;
5036 if (n_blocks != next_block_number)
5039 return block_vector;
5042 /* Given BLOCK_VECTOR which was returned by identify_blocks,
5043 and a revised instruction chain, rebuild the tree structure
5044 of BLOCK nodes to correspond to the new order of RTL.
5045 The new block tree is inserted below TOP_BLOCK.
5046 Returns the current top-level block. */
5049 reorder_blocks (block_vector, block, insns)
5054 tree current_block = block;
5057 if (block_vector == 0)
5060 /* Prune the old trees away, so that it doesn't get in the way. */
5061 BLOCK_SUBBLOCKS (current_block) = 0;
5062 BLOCK_CHAIN (current_block) = 0;
5064 for (insn = insns; insn; insn = NEXT_INSN (insn))
5065 if (GET_CODE (insn) == NOTE)
5067 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5069 tree block = block_vector[NOTE_BLOCK_NUMBER (insn)];
5070 /* If we have seen this block before, copy it. */
5071 if (TREE_ASM_WRITTEN (block))
5072 block = copy_node (block);
5073 BLOCK_SUBBLOCKS (block) = 0;
5074 TREE_ASM_WRITTEN (block) = 1;
5075 BLOCK_SUPERCONTEXT (block) = current_block;
5076 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
5077 BLOCK_SUBBLOCKS (current_block) = block;
5078 current_block = block;
5079 NOTE_SOURCE_FILE (insn) = 0;
5081 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5083 BLOCK_SUBBLOCKS (current_block)
5084 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5085 current_block = BLOCK_SUPERCONTEXT (current_block);
5086 NOTE_SOURCE_FILE (insn) = 0;
5090 BLOCK_SUBBLOCKS (current_block)
5091 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5092 return current_block;
5095 /* Reverse the order of elements in the chain T of blocks,
5096 and return the new head of the chain (old last element). */
5102 register tree prev = 0, decl, next;
5103 for (decl = t; decl; decl = next)
5105 next = BLOCK_CHAIN (decl);
5106 BLOCK_CHAIN (decl) = prev;
5112 /* Count the subblocks of the list starting with BLOCK, and list them
5113 all into the vector VECTOR. Also clear TREE_ASM_WRITTEN in all
5117 all_blocks (block, vector)
5125 TREE_ASM_WRITTEN (block) = 0;
5127 /* Record this block. */
5129 vector[n_blocks] = block;
5133 /* Record the subblocks, and their subblocks... */
5134 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
5135 vector ? vector + n_blocks : 0);
5136 block = BLOCK_CHAIN (block);
5142 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
5143 and initialize static variables for generating RTL for the statements
5147 init_function_start (subr, filename, line)
5152 init_stmt_for_function ();
5154 cse_not_expected = ! optimize;
5156 /* Caller save not needed yet. */
5157 caller_save_needed = 0;
5159 /* No stack slots have been made yet. */
5160 stack_slot_list = 0;
5162 /* There is no stack slot for handling nonlocal gotos. */
5163 nonlocal_goto_handler_slot = 0;
5164 nonlocal_goto_stack_level = 0;
5166 /* No labels have been declared for nonlocal use. */
5167 nonlocal_labels = 0;
5169 /* No function calls so far in this function. */
5170 function_call_count = 0;
5172 /* No parm regs have been allocated.
5173 (This is important for output_inline_function.) */
5174 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
5176 /* Initialize the RTL mechanism. */
5179 /* Initialize the queue of pending postincrement and postdecrements,
5180 and some other info in expr.c. */
5183 /* We haven't done register allocation yet. */
5186 init_const_rtx_hash_table ();
5188 current_function_name = (*decl_printable_name) (subr, 2);
5190 /* Nonzero if this is a nested function that uses a static chain. */
5192 current_function_needs_context
5193 = (decl_function_context (current_function_decl) != 0
5194 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
5196 /* Set if a call to setjmp is seen. */
5197 current_function_calls_setjmp = 0;
5199 /* Set if a call to longjmp is seen. */
5200 current_function_calls_longjmp = 0;
5202 current_function_calls_alloca = 0;
5203 current_function_has_nonlocal_label = 0;
5204 current_function_has_nonlocal_goto = 0;
5205 current_function_contains_functions = 0;
5206 current_function_is_thunk = 0;
5208 current_function_returns_pcc_struct = 0;
5209 current_function_returns_struct = 0;
5210 current_function_epilogue_delay_list = 0;
5211 current_function_uses_const_pool = 0;
5212 current_function_uses_pic_offset_table = 0;
5214 /* We have not yet needed to make a label to jump to for tail-recursion. */
5215 tail_recursion_label = 0;
5217 /* We haven't had a need to make a save area for ap yet. */
5219 arg_pointer_save_area = 0;
5221 /* No stack slots allocated yet. */
5224 /* No SAVE_EXPRs in this function yet. */
5227 /* No RTL_EXPRs in this function yet. */
5230 /* Set up to allocate temporaries. */
5233 /* Within function body, compute a type's size as soon it is laid out. */
5234 immediate_size_expand++;
5236 /* We haven't made any trampolines for this function yet. */
5237 trampoline_list = 0;
5239 init_pending_stack_adjust ();
5240 inhibit_defer_pop = 0;
5242 current_function_outgoing_args_size = 0;
5244 /* Prevent ever trying to delete the first instruction of a function.
5245 Also tell final how to output a linenum before the function prologue. */
5246 emit_line_note (filename, line);
5248 /* Make sure first insn is a note even if we don't want linenums.
5249 This makes sure the first insn will never be deleted.
5250 Also, final expects a note to appear there. */
5251 emit_note (NULL_PTR, NOTE_INSN_DELETED);
5253 /* Set flags used by final.c. */
5254 if (aggregate_value_p (DECL_RESULT (subr)))
5256 #ifdef PCC_STATIC_STRUCT_RETURN
5257 current_function_returns_pcc_struct = 1;
5259 current_function_returns_struct = 1;
5262 /* Warn if this value is an aggregate type,
5263 regardless of which calling convention we are using for it. */
5264 if (warn_aggregate_return
5265 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
5266 warning ("function returns an aggregate");
5268 current_function_returns_pointer
5269 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
5271 /* Indicate that we need to distinguish between the return value of the
5272 present function and the return value of a function being called. */
5273 rtx_equal_function_value_matters = 1;
5275 /* Indicate that we have not instantiated virtual registers yet. */
5276 virtuals_instantiated = 0;
5278 /* Indicate we have no need of a frame pointer yet. */
5279 frame_pointer_needed = 0;
5281 /* By default assume not varargs or stdarg. */
5282 current_function_varargs = 0;
5283 current_function_stdarg = 0;
5286 /* Indicate that the current function uses extra args
5287 not explicitly mentioned in the argument list in any fashion. */
5292 current_function_varargs = 1;
5295 /* Expand a call to __main at the beginning of a possible main function. */
5297 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
5298 #undef HAS_INIT_SECTION
5299 #define HAS_INIT_SECTION
5303 expand_main_function ()
5305 #if !defined (HAS_INIT_SECTION)
5306 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, NAME__MAIN), 0,
5308 #endif /* not HAS_INIT_SECTION */
5311 extern struct obstack permanent_obstack;
5313 /* Start the RTL for a new function, and set variables used for
5315 SUBR is the FUNCTION_DECL node.
5316 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
5317 the function's parameters, which must be run at any return statement. */
5320 expand_function_start (subr, parms_have_cleanups)
5322 int parms_have_cleanups;
5328 /* Make sure volatile mem refs aren't considered
5329 valid operands of arithmetic insns. */
5330 init_recog_no_volatile ();
5332 /* If function gets a static chain arg, store it in the stack frame.
5333 Do this first, so it gets the first stack slot offset. */
5334 if (current_function_needs_context)
5336 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
5338 /* Delay copying static chain if it is not a register to avoid
5339 conflicts with regs used for parameters. */
5340 if (! SMALL_REGISTER_CLASSES
5341 || GET_CODE (static_chain_incoming_rtx) == REG)
5342 emit_move_insn (last_ptr, static_chain_incoming_rtx);
5345 /* If the parameters of this function need cleaning up, get a label
5346 for the beginning of the code which executes those cleanups. This must
5347 be done before doing anything with return_label. */
5348 if (parms_have_cleanups)
5349 cleanup_label = gen_label_rtx ();
5353 /* Make the label for return statements to jump to, if this machine
5354 does not have a one-instruction return and uses an epilogue,
5355 or if it returns a structure, or if it has parm cleanups. */
5357 if (cleanup_label == 0 && HAVE_return
5358 && ! current_function_returns_pcc_struct
5359 && ! (current_function_returns_struct && ! optimize))
5362 return_label = gen_label_rtx ();
5364 return_label = gen_label_rtx ();
5367 /* Initialize rtx used to return the value. */
5368 /* Do this before assign_parms so that we copy the struct value address
5369 before any library calls that assign parms might generate. */
5371 /* Decide whether to return the value in memory or in a register. */
5372 if (aggregate_value_p (DECL_RESULT (subr)))
5374 /* Returning something that won't go in a register. */
5375 register rtx value_address = 0;
5377 #ifdef PCC_STATIC_STRUCT_RETURN
5378 if (current_function_returns_pcc_struct)
5380 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
5381 value_address = assemble_static_space (size);
5386 /* Expect to be passed the address of a place to store the value.
5387 If it is passed as an argument, assign_parms will take care of
5389 if (struct_value_incoming_rtx)
5391 value_address = gen_reg_rtx (Pmode);
5392 emit_move_insn (value_address, struct_value_incoming_rtx);
5397 DECL_RTL (DECL_RESULT (subr))
5398 = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
5399 MEM_IN_STRUCT_P (DECL_RTL (DECL_RESULT (subr)))
5400 = AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
5403 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
5404 /* If return mode is void, this decl rtl should not be used. */
5405 DECL_RTL (DECL_RESULT (subr)) = 0;
5406 else if (parms_have_cleanups)
5408 /* If function will end with cleanup code for parms,
5409 compute the return values into a pseudo reg,
5410 which we will copy into the true return register
5411 after the cleanups are done. */
5413 enum machine_mode mode = DECL_MODE (DECL_RESULT (subr));
5415 #ifdef PROMOTE_FUNCTION_RETURN
5416 tree type = TREE_TYPE (DECL_RESULT (subr));
5417 int unsignedp = TREE_UNSIGNED (type);
5419 mode = promote_mode (type, mode, &unsignedp, 1);
5422 DECL_RTL (DECL_RESULT (subr)) = gen_reg_rtx (mode);
5425 /* Scalar, returned in a register. */
5427 #ifdef FUNCTION_OUTGOING_VALUE
5428 DECL_RTL (DECL_RESULT (subr))
5429 = FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (subr)), subr);
5431 DECL_RTL (DECL_RESULT (subr))
5432 = FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (subr)), subr);
5435 /* Mark this reg as the function's return value. */
5436 if (GET_CODE (DECL_RTL (DECL_RESULT (subr))) == REG)
5438 REG_FUNCTION_VALUE_P (DECL_RTL (DECL_RESULT (subr))) = 1;
5439 /* Needed because we may need to move this to memory
5440 in case it's a named return value whose address is taken. */
5441 DECL_REGISTER (DECL_RESULT (subr)) = 1;
5445 /* Initialize rtx for parameters and local variables.
5446 In some cases this requires emitting insns. */
5448 assign_parms (subr, 0);
5450 /* Copy the static chain now if it wasn't a register. The delay is to
5451 avoid conflicts with the parameter passing registers. */
5453 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
5454 if (GET_CODE (static_chain_incoming_rtx) != REG)
5455 emit_move_insn (last_ptr, static_chain_incoming_rtx);
5457 /* The following was moved from init_function_start.
5458 The move is supposed to make sdb output more accurate. */
5459 /* Indicate the beginning of the function body,
5460 as opposed to parm setup. */
5461 emit_note (NULL_PTR, NOTE_INSN_FUNCTION_BEG);
5463 /* If doing stupid allocation, mark parms as born here. */
5465 if (GET_CODE (get_last_insn ()) != NOTE)
5466 emit_note (NULL_PTR, NOTE_INSN_DELETED);
5467 parm_birth_insn = get_last_insn ();
5471 for (i = LAST_VIRTUAL_REGISTER + 1; i < max_parm_reg; i++)
5472 use_variable (regno_reg_rtx[i]);
5474 if (current_function_internal_arg_pointer != virtual_incoming_args_rtx)
5475 use_variable (current_function_internal_arg_pointer);
5478 context_display = 0;
5479 if (current_function_needs_context)
5481 /* Fetch static chain values for containing functions. */
5482 tem = decl_function_context (current_function_decl);
5483 /* If not doing stupid register allocation copy the static chain
5484 pointer into a pseudo. If we have small register classes, copy
5485 the value from memory if static_chain_incoming_rtx is a REG. If
5486 we do stupid register allocation, we use the stack address
5488 if (tem && ! obey_regdecls)
5490 /* If the static chain originally came in a register, put it back
5491 there, then move it out in the next insn. The reason for
5492 this peculiar code is to satisfy function integration. */
5493 if (SMALL_REGISTER_CLASSES
5494 && GET_CODE (static_chain_incoming_rtx) == REG)
5495 emit_move_insn (static_chain_incoming_rtx, last_ptr);
5496 last_ptr = copy_to_reg (static_chain_incoming_rtx);
5501 tree rtlexp = make_node (RTL_EXPR);
5503 RTL_EXPR_RTL (rtlexp) = last_ptr;
5504 context_display = tree_cons (tem, rtlexp, context_display);
5505 tem = decl_function_context (tem);
5508 /* Chain thru stack frames, assuming pointer to next lexical frame
5509 is found at the place we always store it. */
5510 #ifdef FRAME_GROWS_DOWNWARD
5511 last_ptr = plus_constant (last_ptr, - GET_MODE_SIZE (Pmode));
5513 last_ptr = copy_to_reg (gen_rtx_MEM (Pmode,
5514 memory_address (Pmode, last_ptr)));
5516 /* If we are not optimizing, ensure that we know that this
5517 piece of context is live over the entire function. */
5519 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
5524 /* After the display initializations is where the tail-recursion label
5525 should go, if we end up needing one. Ensure we have a NOTE here
5526 since some things (like trampolines) get placed before this. */
5527 tail_recursion_reentry = emit_note (NULL_PTR, NOTE_INSN_DELETED);
5529 /* Evaluate now the sizes of any types declared among the arguments. */
5530 for (tem = nreverse (get_pending_sizes ()); tem; tem = TREE_CHAIN (tem))
5532 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode,
5533 EXPAND_MEMORY_USE_BAD);
5534 /* Flush the queue in case this parameter declaration has
5539 /* Make sure there is a line number after the function entry setup code. */
5540 force_next_line_note ();
5543 /* Generate RTL for the end of the current function.
5544 FILENAME and LINE are the current position in the source file.
5546 It is up to language-specific callers to do cleanups for parameters--
5547 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
5550 expand_function_end (filename, line, end_bindings)
5558 #ifdef TRAMPOLINE_TEMPLATE
5559 static rtx initial_trampoline;
5562 #ifdef NON_SAVING_SETJMP
5563 /* Don't put any variables in registers if we call setjmp
5564 on a machine that fails to restore the registers. */
5565 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
5567 if (DECL_INITIAL (current_function_decl) != error_mark_node)
5568 setjmp_protect (DECL_INITIAL (current_function_decl));
5570 setjmp_protect_args ();
5574 /* Save the argument pointer if a save area was made for it. */
5575 if (arg_pointer_save_area)
5577 rtx x = gen_move_insn (arg_pointer_save_area, virtual_incoming_args_rtx);
5578 emit_insn_before (x, tail_recursion_reentry);
5581 /* Initialize any trampolines required by this function. */
5582 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5584 tree function = TREE_PURPOSE (link);
5585 rtx context = lookup_static_chain (function);
5586 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
5590 #ifdef TRAMPOLINE_TEMPLATE
5591 /* First make sure this compilation has a template for
5592 initializing trampolines. */
5593 if (initial_trampoline == 0)
5595 end_temporary_allocation ();
5597 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
5598 resume_temporary_allocation ();
5602 /* Generate insns to initialize the trampoline. */
5604 tramp = round_trampoline_addr (XEXP (tramp, 0));
5605 #ifdef TRAMPOLINE_TEMPLATE
5606 blktramp = change_address (initial_trampoline, BLKmode, tramp);
5607 emit_block_move (blktramp, initial_trampoline,
5608 GEN_INT (TRAMPOLINE_SIZE),
5609 TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
5611 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
5615 /* Put those insns at entry to the containing function (this one). */
5616 emit_insns_before (seq, tail_recursion_reentry);
5619 /* If we are doing stack checking and this function makes calls,
5620 do a stack probe at the start of the function to ensure we have enough
5621 space for another stack frame. */
5622 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
5626 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
5627 if (GET_CODE (insn) == CALL_INSN)
5630 probe_stack_range (STACK_CHECK_PROTECT,
5631 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
5634 emit_insns_before (seq, tail_recursion_reentry);
5639 /* Warn about unused parms if extra warnings were specified. */
5640 if (warn_unused && extra_warnings)
5644 for (decl = DECL_ARGUMENTS (current_function_decl);
5645 decl; decl = TREE_CHAIN (decl))
5646 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
5647 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
5648 warning_with_decl (decl, "unused parameter `%s'");
5651 /* Delete handlers for nonlocal gotos if nothing uses them. */
5652 if (nonlocal_goto_handler_slot != 0 && !current_function_has_nonlocal_label)
5655 /* End any sequences that failed to be closed due to syntax errors. */
5656 while (in_sequence_p ())
5659 /* Outside function body, can't compute type's actual size
5660 until next function's body starts. */
5661 immediate_size_expand--;
5663 /* If doing stupid register allocation,
5664 mark register parms as dying here. */
5669 for (i = LAST_VIRTUAL_REGISTER + 1; i < max_parm_reg; i++)
5670 use_variable (regno_reg_rtx[i]);
5672 /* Likewise for the regs of all the SAVE_EXPRs in the function. */
5674 for (tem = save_expr_regs; tem; tem = XEXP (tem, 1))
5676 use_variable (XEXP (tem, 0));
5677 use_variable_after (XEXP (tem, 0), parm_birth_insn);
5680 if (current_function_internal_arg_pointer != virtual_incoming_args_rtx)
5681 use_variable (current_function_internal_arg_pointer);
5684 clear_pending_stack_adjust ();
5685 do_pending_stack_adjust ();
5687 /* Mark the end of the function body.
5688 If control reaches this insn, the function can drop through
5689 without returning a value. */
5690 emit_note (NULL_PTR, NOTE_INSN_FUNCTION_END);
5692 /* Must mark the last line number note in the function, so that the test
5693 coverage code can avoid counting the last line twice. This just tells
5694 the code to ignore the immediately following line note, since there
5695 already exists a copy of this note somewhere above. This line number
5696 note is still needed for debugging though, so we can't delete it. */
5697 if (flag_test_coverage)
5698 emit_note (NULL_PTR, NOTE_REPEATED_LINE_NUMBER);
5700 /* Output a linenumber for the end of the function.
5701 SDB depends on this. */
5702 emit_line_note_force (filename, line);
5704 /* Output the label for the actual return from the function,
5705 if one is expected. This happens either because a function epilogue
5706 is used instead of a return instruction, or because a return was done
5707 with a goto in order to run local cleanups, or because of pcc-style
5708 structure returning. */
5711 emit_label (return_label);
5713 /* C++ uses this. */
5715 expand_end_bindings (0, 0, 0);
5717 /* Now handle any leftover exception regions that may have been
5718 created for the parameters. */
5720 rtx last = get_last_insn ();
5723 expand_leftover_cleanups ();
5725 /* If the above emitted any code, may sure we jump around it. */
5726 if (last != get_last_insn ())
5728 label = gen_label_rtx ();
5729 last = emit_jump_insn_after (gen_jump (label), last);
5730 last = emit_barrier_after (last);
5735 /* If we had calls to alloca, and this machine needs
5736 an accurate stack pointer to exit the function,
5737 insert some code to save and restore the stack pointer. */
5738 #ifdef EXIT_IGNORE_STACK
5739 if (! EXIT_IGNORE_STACK)
5741 if (current_function_calls_alloca)
5745 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
5746 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
5749 /* If scalar return value was computed in a pseudo-reg,
5750 copy that to the hard return register. */
5751 if (DECL_RTL (DECL_RESULT (current_function_decl)) != 0
5752 && GET_CODE (DECL_RTL (DECL_RESULT (current_function_decl))) == REG
5753 && (REGNO (DECL_RTL (DECL_RESULT (current_function_decl)))
5754 >= FIRST_PSEUDO_REGISTER))
5756 rtx real_decl_result;
5758 #ifdef FUNCTION_OUTGOING_VALUE
5760 = FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl)),
5761 current_function_decl);
5764 = FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl)),
5765 current_function_decl);
5767 REG_FUNCTION_VALUE_P (real_decl_result) = 1;
5768 /* If this is a BLKmode structure being returned in registers, then use
5769 the mode computed in expand_return. */
5770 if (GET_MODE (real_decl_result) == BLKmode)
5771 PUT_MODE (real_decl_result,
5772 GET_MODE (DECL_RTL (DECL_RESULT (current_function_decl))));
5773 emit_move_insn (real_decl_result,
5774 DECL_RTL (DECL_RESULT (current_function_decl)));
5775 emit_insn (gen_rtx_USE (VOIDmode, real_decl_result));
5777 /* The delay slot scheduler assumes that current_function_return_rtx
5778 holds the hard register containing the return value, not a temporary
5780 current_function_return_rtx = real_decl_result;
5783 /* If returning a structure, arrange to return the address of the value
5784 in a place where debuggers expect to find it.
5786 If returning a structure PCC style,
5787 the caller also depends on this value.
5788 And current_function_returns_pcc_struct is not necessarily set. */
5789 if (current_function_returns_struct
5790 || current_function_returns_pcc_struct)
5792 rtx value_address = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
5793 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
5794 #ifdef FUNCTION_OUTGOING_VALUE
5796 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
5797 current_function_decl);
5800 = FUNCTION_VALUE (build_pointer_type (type),
5801 current_function_decl);
5804 /* Mark this as a function return value so integrate will delete the
5805 assignment and USE below when inlining this function. */
5806 REG_FUNCTION_VALUE_P (outgoing) = 1;
5808 emit_move_insn (outgoing, value_address);
5809 use_variable (outgoing);
5812 /* Output a return insn if we are using one.
5813 Otherwise, let the rtl chain end here, to drop through
5814 into the epilogue. */
5819 emit_jump_insn (gen_return ());
5824 /* Fix up any gotos that jumped out to the outermost
5825 binding level of the function.
5826 Must follow emitting RETURN_LABEL. */
5828 /* If you have any cleanups to do at this point,
5829 and they need to create temporary variables,
5830 then you will lose. */
5831 expand_fixups (get_insns ());
5834 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
5836 static int *prologue;
5837 static int *epilogue;
5839 /* Create an array that records the INSN_UIDs of INSNS (either a sequence
5840 or a single insn). */
5843 record_insns (insns)
5848 if (GET_CODE (insns) == SEQUENCE)
5850 int len = XVECLEN (insns, 0);
5851 vec = (int *) oballoc ((len + 1) * sizeof (int));
5854 vec[len] = INSN_UID (XVECEXP (insns, 0, len));
5858 vec = (int *) oballoc (2 * sizeof (int));
5859 vec[0] = INSN_UID (insns);
5865 /* Determine how many INSN_UIDs in VEC are part of INSN. */
5868 contains (insn, vec)
5874 if (GET_CODE (insn) == INSN
5875 && GET_CODE (PATTERN (insn)) == SEQUENCE)
5878 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
5879 for (j = 0; vec[j]; j++)
5880 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == vec[j])
5886 for (j = 0; vec[j]; j++)
5887 if (INSN_UID (insn) == vec[j])
5893 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
5894 this into place with notes indicating where the prologue ends and where
5895 the epilogue begins. Update the basic block information when possible. */
5898 thread_prologue_and_epilogue_insns (f)
5901 #ifdef HAVE_prologue
5906 /* The first insn (a NOTE_INSN_DELETED) is followed by zero or more
5907 prologue insns and a NOTE_INSN_PROLOGUE_END. */
5908 emit_note_after (NOTE_INSN_PROLOGUE_END, f);
5909 seq = gen_prologue ();
5910 head = emit_insn_after (seq, f);
5912 /* Include the new prologue insns in the first block. Ignore them
5913 if they form a basic block unto themselves. */
5914 if (basic_block_head && n_basic_blocks
5915 && GET_CODE (basic_block_head[0]) != CODE_LABEL)
5916 basic_block_head[0] = NEXT_INSN (f);
5918 /* Retain a map of the prologue insns. */
5919 prologue = record_insns (GET_CODE (seq) == SEQUENCE ? seq : head);
5925 #ifdef HAVE_epilogue
5928 rtx insn = get_last_insn ();
5929 rtx prev = prev_nonnote_insn (insn);
5931 /* If we end with a BARRIER, we don't need an epilogue. */
5932 if (! (prev && GET_CODE (prev) == BARRIER))
5938 /* The last basic block ends with a NOTE_INSN_EPILOGUE_BEG, the
5939 epilogue insns, the USE insns at the end of a function,
5940 the jump insn that returns, and then a BARRIER. */
5942 /* Move the USE insns at the end of a function onto a list. */
5944 && GET_CODE (prev) == INSN
5945 && GET_CODE (PATTERN (prev)) == USE)
5948 prev = prev_nonnote_insn (prev);
5950 NEXT_INSN (PREV_INSN (tem)) = NEXT_INSN (tem);
5951 PREV_INSN (NEXT_INSN (tem)) = PREV_INSN (tem);
5954 NEXT_INSN (tem) = first_use;
5955 PREV_INSN (first_use) = tem;
5962 emit_barrier_after (insn);
5964 seq = gen_epilogue ();
5965 tail = emit_jump_insn_after (seq, insn);
5967 /* Insert the USE insns immediately before the return insn, which
5968 must be the first instruction before the final barrier. */
5971 tem = prev_nonnote_insn (get_last_insn ());
5972 NEXT_INSN (PREV_INSN (tem)) = first_use;
5973 PREV_INSN (first_use) = PREV_INSN (tem);
5974 PREV_INSN (tem) = last_use;
5975 NEXT_INSN (last_use) = tem;
5978 emit_note_after (NOTE_INSN_EPILOGUE_BEG, insn);
5980 /* Include the new epilogue insns in the last block. Ignore
5981 them if they form a basic block unto themselves. */
5982 if (basic_block_end && n_basic_blocks
5983 && GET_CODE (basic_block_end[n_basic_blocks - 1]) != JUMP_INSN)
5984 basic_block_end[n_basic_blocks - 1] = tail;
5986 /* Retain a map of the epilogue insns. */
5987 epilogue = record_insns (GET_CODE (seq) == SEQUENCE ? seq : tail);
5995 /* Reposition the prologue-end and epilogue-begin notes after instruction
5996 scheduling and delayed branch scheduling. */
5999 reposition_prologue_and_epilogue_notes (f)
6002 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
6003 /* Reposition the prologue and epilogue notes. */
6011 register rtx insn, note = 0;
6013 /* Scan from the beginning until we reach the last prologue insn.
6014 We apparently can't depend on basic_block_{head,end} after
6016 for (len = 0; prologue[len]; len++)
6018 for (insn = f; len && insn; insn = NEXT_INSN (insn))
6020 if (GET_CODE (insn) == NOTE)
6022 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
6025 else if ((len -= contains (insn, prologue)) == 0)
6027 /* Find the prologue-end note if we haven't already, and
6028 move it to just after the last prologue insn. */
6031 for (note = insn; (note = NEXT_INSN (note));)
6032 if (GET_CODE (note) == NOTE
6033 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
6036 next = NEXT_INSN (note);
6037 prev = PREV_INSN (note);
6039 NEXT_INSN (prev) = next;
6041 PREV_INSN (next) = prev;
6042 add_insn_after (note, insn);
6049 register rtx insn, note = 0;
6051 /* Scan from the end until we reach the first epilogue insn.
6052 We apparently can't depend on basic_block_{head,end} after
6054 for (len = 0; epilogue[len]; len++)
6056 for (insn = get_last_insn (); len && insn; insn = PREV_INSN (insn))
6058 if (GET_CODE (insn) == NOTE)
6060 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
6063 else if ((len -= contains (insn, epilogue)) == 0)
6065 /* Find the epilogue-begin note if we haven't already, and
6066 move it to just before the first epilogue insn. */
6069 for (note = insn; (note = PREV_INSN (note));)
6070 if (GET_CODE (note) == NOTE
6071 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
6074 next = NEXT_INSN (note);
6075 prev = PREV_INSN (note);
6077 NEXT_INSN (prev) = next;
6079 PREV_INSN (next) = prev;
6080 add_insn_after (note, PREV_INSN (insn));
6085 #endif /* HAVE_prologue or HAVE_epilogue */