1 /* Expands front end tree to back end RTL for GNU C-Compiler
2 Copyright (C) 1987, 88, 89, 91-97, 1998 Free Software Foundation, Inc.
4 This file is part of GNU CC.
6 GNU CC is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 GNU CC is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GNU CC; see the file COPYING. If not, write to
18 the Free Software Foundation, 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
22 /* This file handles the generation of rtl code from tree structure
23 at the level of the function as a whole.
24 It creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 `expand_function_start' is called at the beginning of a function,
28 before the function body is parsed, and `expand_function_end' is
29 called after parsing the body.
31 Call `assign_stack_local' to allocate a stack slot for a local variable.
32 This is usually done during the RTL generation for the function body,
33 but it can also be done in the reload pass when a pseudo-register does
34 not get a hard register.
36 Call `put_var_into_stack' when you learn, belatedly, that a variable
37 previously given a pseudo-register must in fact go in the stack.
38 This function changes the DECL_RTL to be a stack slot instead of a reg
39 then scans all the RTL instructions so far generated to correct them. */
48 #include "insn-flags.h"
50 #include "insn-codes.h"
52 #include "hard-reg-set.h"
53 #include "insn-config.h"
56 #include "basic-block.h"
60 #ifndef TRAMPOLINE_ALIGNMENT
61 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
64 /* Some systems use __main in a way incompatible with its use in gcc, in these
65 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
66 give the same symbol without quotes for an alternative entry point. You
67 must define both, or neither. */
69 #define NAME__MAIN "__main"
70 #define SYMBOL__MAIN __main
73 /* Round a value to the lowest integer less than it that is a multiple of
74 the required alignment. Avoid using division in case the value is
75 negative. Assume the alignment is a power of two. */
76 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
78 /* Similar, but round to the next highest integer that meets the
80 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
82 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
83 during rtl generation. If they are different register numbers, this is
84 always true. It may also be true if
85 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
86 generation. See fix_lexical_addr for details. */
88 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
89 #define NEED_SEPARATE_AP
92 /* Number of bytes of args popped by function being compiled on its return.
93 Zero if no bytes are to be popped.
94 May affect compilation of return insn or of function epilogue. */
96 int current_function_pops_args;
98 /* Nonzero if function being compiled needs to be given an address
99 where the value should be stored. */
101 int current_function_returns_struct;
103 /* Nonzero if function being compiled needs to
104 return the address of where it has put a structure value. */
106 int current_function_returns_pcc_struct;
108 /* Nonzero if function being compiled needs to be passed a static chain. */
110 int current_function_needs_context;
112 /* Nonzero if function being compiled can call setjmp. */
114 int current_function_calls_setjmp;
116 /* Nonzero if function being compiled can call longjmp. */
118 int current_function_calls_longjmp;
120 /* Nonzero if function being compiled receives nonlocal gotos
121 from nested functions. */
123 int current_function_has_nonlocal_label;
125 /* Nonzero if function being compiled has nonlocal gotos to parent
128 int current_function_has_nonlocal_goto;
130 /* Nonzero if this function has a computed goto.
132 It is computed during find_basic_blocks or during stupid life
135 int current_function_has_computed_jump;
137 /* Nonzero if function being compiled contains nested functions. */
139 int current_function_contains_functions;
141 /* Nonzero if the current function is a thunk (a lightweight function that
142 just adjusts one of its arguments and forwards to another function), so
143 we should try to cut corners where we can. */
144 int current_function_is_thunk;
146 /* Nonzero if function being compiled can call alloca,
147 either as a subroutine or builtin. */
149 int current_function_calls_alloca;
151 /* Nonzero if the current function returns a pointer type */
153 int current_function_returns_pointer;
155 /* If some insns can be deferred to the delay slots of the epilogue, the
156 delay list for them is recorded here. */
158 rtx current_function_epilogue_delay_list;
160 /* If function's args have a fixed size, this is that size, in bytes.
162 May affect compilation of return insn or of function epilogue. */
164 int current_function_args_size;
166 /* # bytes the prologue should push and pretend that the caller pushed them.
167 The prologue must do this, but only if parms can be passed in registers. */
169 int current_function_pretend_args_size;
171 /* # of bytes of outgoing arguments. If ACCUMULATE_OUTGOING_ARGS is
172 defined, the needed space is pushed by the prologue. */
174 int current_function_outgoing_args_size;
176 /* This is the offset from the arg pointer to the place where the first
177 anonymous arg can be found, if there is one. */
179 rtx current_function_arg_offset_rtx;
181 /* Nonzero if current function uses varargs.h or equivalent.
182 Zero for functions that use stdarg.h. */
184 int current_function_varargs;
186 /* Nonzero if current function uses stdarg.h or equivalent.
187 Zero for functions that use varargs.h. */
189 int current_function_stdarg;
191 /* Quantities of various kinds of registers
192 used for the current function's args. */
194 CUMULATIVE_ARGS current_function_args_info;
196 /* Name of function now being compiled. */
198 char *current_function_name;
200 /* If non-zero, an RTL expression for the location at which the current
201 function returns its result. If the current function returns its
202 result in a register, current_function_return_rtx will always be
203 the hard register containing the result. */
205 rtx current_function_return_rtx;
207 /* Nonzero if the current function uses the constant pool. */
209 int current_function_uses_const_pool;
211 /* Nonzero if the current function uses pic_offset_table_rtx. */
212 int current_function_uses_pic_offset_table;
214 /* The arg pointer hard register, or the pseudo into which it was copied. */
215 rtx current_function_internal_arg_pointer;
217 /* Language-specific reason why the current function cannot be made inline. */
218 char *current_function_cannot_inline;
220 /* Nonzero if instrumentation calls for function entry and exit should be
222 int current_function_instrument_entry_exit;
224 /* The FUNCTION_DECL for an inline function currently being expanded. */
225 tree inline_function_decl;
227 /* Number of function calls seen so far in current function. */
229 int function_call_count;
231 /* List (chain of TREE_LIST) of LABEL_DECLs for all nonlocal labels
232 (labels to which there can be nonlocal gotos from nested functions)
235 tree nonlocal_labels;
237 /* RTX for stack slot that holds the current handler for nonlocal gotos.
238 Zero when function does not have nonlocal labels. */
240 rtx nonlocal_goto_handler_slot;
242 /* RTX for stack slot that holds the stack pointer value to restore
244 Zero when function does not have nonlocal labels. */
246 rtx nonlocal_goto_stack_level;
248 /* Label that will go on parm cleanup code, if any.
249 Jumping to this label runs cleanup code for parameters, if
250 such code must be run. Following this code is the logical return label. */
254 /* Label that will go on function epilogue.
255 Jumping to this label serves as a "return" instruction
256 on machines which require execution of the epilogue on all returns. */
260 /* List (chain of EXPR_LISTs) of pseudo-regs of SAVE_EXPRs.
261 So we can mark them all live at the end of the function, if nonopt. */
264 /* List (chain of EXPR_LISTs) of all stack slots in this function.
265 Made for the sake of unshare_all_rtl. */
268 /* Chain of all RTL_EXPRs that have insns in them. */
271 /* Label to jump back to for tail recursion, or 0 if we have
272 not yet needed one for this function. */
273 rtx tail_recursion_label;
275 /* Place after which to insert the tail_recursion_label if we need one. */
276 rtx tail_recursion_reentry;
278 /* Location at which to save the argument pointer if it will need to be
279 referenced. There are two cases where this is done: if nonlocal gotos
280 exist, or if vars stored at an offset from the argument pointer will be
281 needed by inner routines. */
283 rtx arg_pointer_save_area;
285 /* Offset to end of allocated area of stack frame.
286 If stack grows down, this is the address of the last stack slot allocated.
287 If stack grows up, this is the address for the next slot. */
288 HOST_WIDE_INT frame_offset;
290 /* List (chain of TREE_LISTs) of static chains for containing functions.
291 Each link has a FUNCTION_DECL in the TREE_PURPOSE and a reg rtx
292 in an RTL_EXPR in the TREE_VALUE. */
293 static tree context_display;
295 /* List (chain of TREE_LISTs) of trampolines for nested functions.
296 The trampoline sets up the static chain and jumps to the function.
297 We supply the trampoline's address when the function's address is requested.
299 Each link has a FUNCTION_DECL in the TREE_PURPOSE and a reg rtx
300 in an RTL_EXPR in the TREE_VALUE. */
301 static tree trampoline_list;
303 /* Insn after which register parms and SAVE_EXPRs are born, if nonopt. */
304 static rtx parm_birth_insn;
307 /* Nonzero if a stack slot has been generated whose address is not
308 actually valid. It means that the generated rtl must all be scanned
309 to detect and correct the invalid addresses where they occur. */
310 static int invalid_stack_slot;
313 /* Last insn of those whose job was to put parms into their nominal homes. */
314 static rtx last_parm_insn;
316 /* 1 + last pseudo register number possibly used for loading a copy
317 of a parameter of this function. */
320 /* Vector indexed by REGNO, containing location on stack in which
321 to put the parm which is nominally in pseudo register REGNO,
322 if we discover that that parm must go in the stack. The highest
323 element in this vector is one less than MAX_PARM_REG, above. */
324 rtx *parm_reg_stack_loc;
326 /* Nonzero once virtual register instantiation has been done.
327 assign_stack_local uses frame_pointer_rtx when this is nonzero. */
328 static int virtuals_instantiated;
330 /* These variables hold pointers to functions to
331 save and restore machine-specific data,
332 in push_function_context and pop_function_context. */
333 void (*save_machine_status) PROTO((struct function *));
334 void (*restore_machine_status) PROTO((struct function *));
336 /* Nonzero if we need to distinguish between the return value of this function
337 and the return value of a function called by this function. This helps
340 extern int rtx_equal_function_value_matters;
341 extern tree sequence_rtl_expr;
343 /* In order to evaluate some expressions, such as function calls returning
344 structures in memory, we need to temporarily allocate stack locations.
345 We record each allocated temporary in the following structure.
347 Associated with each temporary slot is a nesting level. When we pop up
348 one level, all temporaries associated with the previous level are freed.
349 Normally, all temporaries are freed after the execution of the statement
350 in which they were created. However, if we are inside a ({...}) grouping,
351 the result may be in a temporary and hence must be preserved. If the
352 result could be in a temporary, we preserve it if we can determine which
353 one it is in. If we cannot determine which temporary may contain the
354 result, all temporaries are preserved. A temporary is preserved by
355 pretending it was allocated at the previous nesting level.
357 Automatic variables are also assigned temporary slots, at the nesting
358 level where they are defined. They are marked a "kept" so that
359 free_temp_slots will not free them. */
363 /* Points to next temporary slot. */
364 struct temp_slot *next;
365 /* The rtx to used to reference the slot. */
367 /* The rtx used to represent the address if not the address of the
368 slot above. May be an EXPR_LIST if multiple addresses exist. */
370 /* The size, in units, of the slot. */
372 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
374 /* Non-zero if this temporary is currently in use. */
376 /* Non-zero if this temporary has its address taken. */
378 /* Nesting level at which this slot is being used. */
380 /* Non-zero if this should survive a call to free_temp_slots. */
382 /* The offset of the slot from the frame_pointer, including extra space
383 for alignment. This info is for combine_temp_slots. */
384 HOST_WIDE_INT base_offset;
385 /* The size of the slot, including extra space for alignment. This
386 info is for combine_temp_slots. */
387 HOST_WIDE_INT full_size;
390 /* List of all temporaries allocated, both available and in use. */
392 struct temp_slot *temp_slots;
394 /* Current nesting level for temporaries. */
398 /* Current nesting level for variables in a block. */
400 int var_temp_slot_level;
402 /* When temporaries are created by TARGET_EXPRs, they are created at
403 this level of temp_slot_level, so that they can remain allocated
404 until no longer needed. CLEANUP_POINT_EXPRs define the lifetime
406 int target_temp_slot_level;
408 /* This structure is used to record MEMs or pseudos used to replace VAR, any
409 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
410 maintain this list in case two operands of an insn were required to match;
411 in that case we must ensure we use the same replacement. */
413 struct fixup_replacement
417 struct fixup_replacement *next;
420 /* Forward declarations. */
422 static rtx assign_outer_stack_local PROTO ((enum machine_mode, HOST_WIDE_INT,
423 int, struct function *));
424 static struct temp_slot *find_temp_slot_from_address PROTO((rtx));
425 static void put_reg_into_stack PROTO((struct function *, rtx, tree,
426 enum machine_mode, enum machine_mode,
428 static void fixup_var_refs PROTO((rtx, enum machine_mode, int));
429 static struct fixup_replacement
430 *find_fixup_replacement PROTO((struct fixup_replacement **, rtx));
431 static void fixup_var_refs_insns PROTO((rtx, enum machine_mode, int,
433 static void fixup_var_refs_1 PROTO((rtx, enum machine_mode, rtx *, rtx,
434 struct fixup_replacement **));
435 static rtx fixup_memory_subreg PROTO((rtx, rtx, int));
436 static rtx walk_fixup_memory_subreg PROTO((rtx, rtx, int));
437 static rtx fixup_stack_1 PROTO((rtx, rtx));
438 static void optimize_bit_field PROTO((rtx, rtx, rtx *));
439 static void instantiate_decls PROTO((tree, int));
440 static void instantiate_decls_1 PROTO((tree, int));
441 static void instantiate_decl PROTO((rtx, int, int));
442 static int instantiate_virtual_regs_1 PROTO((rtx *, rtx, int));
443 static void delete_handlers PROTO((void));
444 static void pad_to_arg_alignment PROTO((struct args_size *, int));
445 #ifndef ARGS_GROW_DOWNWARD
446 static void pad_below PROTO((struct args_size *, enum machine_mode,
449 #ifdef ARGS_GROW_DOWNWARD
450 static tree round_down PROTO((tree, int));
452 static rtx round_trampoline_addr PROTO((rtx));
453 static tree blocks_nreverse PROTO((tree));
454 static int all_blocks PROTO((tree, tree *));
455 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
456 static int *record_insns PROTO((rtx));
457 static int contains PROTO((rtx, int *));
458 #endif /* HAVE_prologue || HAVE_epilogue */
459 static void put_addressof_into_stack PROTO((rtx));
460 static void purge_addressof_1 PROTO((rtx *, rtx, int, int));
462 /* Pointer to chain of `struct function' for containing functions. */
463 struct function *outer_function_chain;
465 /* Given a function decl for a containing function,
466 return the `struct function' for it. */
469 find_function_data (decl)
474 for (p = outer_function_chain; p; p = p->next)
481 /* Save the current context for compilation of a nested function.
482 This is called from language-specific code.
483 The caller is responsible for saving any language-specific status,
484 since this function knows only about language-independent variables. */
487 push_function_context_to (context)
490 struct function *p = (struct function *) xmalloc (sizeof (struct function));
492 p->next = outer_function_chain;
493 outer_function_chain = p;
495 p->name = current_function_name;
496 p->decl = current_function_decl;
497 p->pops_args = current_function_pops_args;
498 p->returns_struct = current_function_returns_struct;
499 p->returns_pcc_struct = current_function_returns_pcc_struct;
500 p->returns_pointer = current_function_returns_pointer;
501 p->needs_context = current_function_needs_context;
502 p->calls_setjmp = current_function_calls_setjmp;
503 p->calls_longjmp = current_function_calls_longjmp;
504 p->calls_alloca = current_function_calls_alloca;
505 p->has_nonlocal_label = current_function_has_nonlocal_label;
506 p->has_nonlocal_goto = current_function_has_nonlocal_goto;
507 p->contains_functions = current_function_contains_functions;
508 p->is_thunk = current_function_is_thunk;
509 p->args_size = current_function_args_size;
510 p->pretend_args_size = current_function_pretend_args_size;
511 p->arg_offset_rtx = current_function_arg_offset_rtx;
512 p->varargs = current_function_varargs;
513 p->stdarg = current_function_stdarg;
514 p->uses_const_pool = current_function_uses_const_pool;
515 p->uses_pic_offset_table = current_function_uses_pic_offset_table;
516 p->internal_arg_pointer = current_function_internal_arg_pointer;
517 p->cannot_inline = current_function_cannot_inline;
518 p->max_parm_reg = max_parm_reg;
519 p->parm_reg_stack_loc = parm_reg_stack_loc;
520 p->outgoing_args_size = current_function_outgoing_args_size;
521 p->return_rtx = current_function_return_rtx;
522 p->nonlocal_goto_handler_slot = nonlocal_goto_handler_slot;
523 p->nonlocal_goto_stack_level = nonlocal_goto_stack_level;
524 p->nonlocal_labels = nonlocal_labels;
525 p->cleanup_label = cleanup_label;
526 p->return_label = return_label;
527 p->save_expr_regs = save_expr_regs;
528 p->stack_slot_list = stack_slot_list;
529 p->parm_birth_insn = parm_birth_insn;
530 p->frame_offset = frame_offset;
531 p->tail_recursion_label = tail_recursion_label;
532 p->tail_recursion_reentry = tail_recursion_reentry;
533 p->arg_pointer_save_area = arg_pointer_save_area;
534 p->rtl_expr_chain = rtl_expr_chain;
535 p->last_parm_insn = last_parm_insn;
536 p->context_display = context_display;
537 p->trampoline_list = trampoline_list;
538 p->function_call_count = function_call_count;
539 p->temp_slots = temp_slots;
540 p->temp_slot_level = temp_slot_level;
541 p->target_temp_slot_level = target_temp_slot_level;
542 p->var_temp_slot_level = var_temp_slot_level;
543 p->fixup_var_refs_queue = 0;
544 p->epilogue_delay_list = current_function_epilogue_delay_list;
545 p->args_info = current_function_args_info;
546 p->instrument_entry_exit = current_function_instrument_entry_exit;
548 save_tree_status (p, context);
549 save_storage_status (p);
550 save_emit_status (p);
551 save_expr_status (p);
552 save_stmt_status (p);
553 save_varasm_status (p, context);
554 if (save_machine_status)
555 (*save_machine_status) (p);
559 push_function_context ()
561 push_function_context_to (current_function_decl);
564 /* Restore the last saved context, at the end of a nested function.
565 This function is called from language-specific code. */
568 pop_function_context_from (context)
571 struct function *p = outer_function_chain;
572 struct var_refs_queue *queue;
574 outer_function_chain = p->next;
576 current_function_contains_functions
577 = p->contains_functions || p->inline_obstacks
578 || context == current_function_decl;
579 current_function_name = p->name;
580 current_function_decl = p->decl;
581 current_function_pops_args = p->pops_args;
582 current_function_returns_struct = p->returns_struct;
583 current_function_returns_pcc_struct = p->returns_pcc_struct;
584 current_function_returns_pointer = p->returns_pointer;
585 current_function_needs_context = p->needs_context;
586 current_function_calls_setjmp = p->calls_setjmp;
587 current_function_calls_longjmp = p->calls_longjmp;
588 current_function_calls_alloca = p->calls_alloca;
589 current_function_has_nonlocal_label = p->has_nonlocal_label;
590 current_function_has_nonlocal_goto = p->has_nonlocal_goto;
591 current_function_is_thunk = p->is_thunk;
592 current_function_args_size = p->args_size;
593 current_function_pretend_args_size = p->pretend_args_size;
594 current_function_arg_offset_rtx = p->arg_offset_rtx;
595 current_function_varargs = p->varargs;
596 current_function_stdarg = p->stdarg;
597 current_function_uses_const_pool = p->uses_const_pool;
598 current_function_uses_pic_offset_table = p->uses_pic_offset_table;
599 current_function_internal_arg_pointer = p->internal_arg_pointer;
600 current_function_cannot_inline = p->cannot_inline;
601 max_parm_reg = p->max_parm_reg;
602 parm_reg_stack_loc = p->parm_reg_stack_loc;
603 current_function_outgoing_args_size = p->outgoing_args_size;
604 current_function_return_rtx = p->return_rtx;
605 nonlocal_goto_handler_slot = p->nonlocal_goto_handler_slot;
606 nonlocal_goto_stack_level = p->nonlocal_goto_stack_level;
607 nonlocal_labels = p->nonlocal_labels;
608 cleanup_label = p->cleanup_label;
609 return_label = p->return_label;
610 save_expr_regs = p->save_expr_regs;
611 stack_slot_list = p->stack_slot_list;
612 parm_birth_insn = p->parm_birth_insn;
613 frame_offset = p->frame_offset;
614 tail_recursion_label = p->tail_recursion_label;
615 tail_recursion_reentry = p->tail_recursion_reentry;
616 arg_pointer_save_area = p->arg_pointer_save_area;
617 rtl_expr_chain = p->rtl_expr_chain;
618 last_parm_insn = p->last_parm_insn;
619 context_display = p->context_display;
620 trampoline_list = p->trampoline_list;
621 function_call_count = p->function_call_count;
622 temp_slots = p->temp_slots;
623 temp_slot_level = p->temp_slot_level;
624 target_temp_slot_level = p->target_temp_slot_level;
625 var_temp_slot_level = p->var_temp_slot_level;
626 current_function_epilogue_delay_list = p->epilogue_delay_list;
628 current_function_args_info = p->args_info;
629 current_function_instrument_entry_exit = p->instrument_entry_exit;
631 restore_tree_status (p, context);
632 restore_storage_status (p);
633 restore_expr_status (p);
634 restore_emit_status (p);
635 restore_stmt_status (p);
636 restore_varasm_status (p);
638 if (restore_machine_status)
639 (*restore_machine_status) (p);
641 /* Finish doing put_var_into_stack for any of our variables
642 which became addressable during the nested function. */
643 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
644 fixup_var_refs (queue->modified, queue->promoted_mode, queue->unsignedp);
648 /* Reset variables that have known state during rtx generation. */
649 rtx_equal_function_value_matters = 1;
650 virtuals_instantiated = 0;
653 void pop_function_context ()
655 pop_function_context_from (current_function_decl);
658 /* Allocate fixed slots in the stack frame of the current function. */
660 /* Return size needed for stack frame based on slots so far allocated.
661 This size counts from zero. It is not rounded to STACK_BOUNDARY;
662 the caller may have to do that. */
667 #ifdef FRAME_GROWS_DOWNWARD
668 return -frame_offset;
674 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
675 with machine mode MODE.
677 ALIGN controls the amount of alignment for the address of the slot:
678 0 means according to MODE,
679 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
680 positive specifies alignment boundary in bits.
682 We do not round to stack_boundary here. */
685 assign_stack_local (mode, size, align)
686 enum machine_mode mode;
690 register rtx x, addr;
691 int bigend_correction = 0;
696 alignment = GET_MODE_ALIGNMENT (mode) / BITS_PER_UNIT;
698 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
700 else if (align == -1)
702 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
703 size = CEIL_ROUND (size, alignment);
706 alignment = align / BITS_PER_UNIT;
708 /* Round frame offset to that alignment.
709 We must be careful here, since FRAME_OFFSET might be negative and
710 division with a negative dividend isn't as well defined as we might
711 like. So we instead assume that ALIGNMENT is a power of two and
712 use logical operations which are unambiguous. */
713 #ifdef FRAME_GROWS_DOWNWARD
714 frame_offset = FLOOR_ROUND (frame_offset, alignment);
716 frame_offset = CEIL_ROUND (frame_offset, alignment);
719 /* On a big-endian machine, if we are allocating more space than we will use,
720 use the least significant bytes of those that are allocated. */
721 if (BYTES_BIG_ENDIAN && mode != BLKmode)
722 bigend_correction = size - GET_MODE_SIZE (mode);
724 #ifdef FRAME_GROWS_DOWNWARD
725 frame_offset -= size;
728 /* If we have already instantiated virtual registers, return the actual
729 address relative to the frame pointer. */
730 if (virtuals_instantiated)
731 addr = plus_constant (frame_pointer_rtx,
732 (frame_offset + bigend_correction
733 + STARTING_FRAME_OFFSET));
735 addr = plus_constant (virtual_stack_vars_rtx,
736 frame_offset + bigend_correction);
738 #ifndef FRAME_GROWS_DOWNWARD
739 frame_offset += size;
742 x = gen_rtx_MEM (mode, addr);
744 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, x, stack_slot_list);
749 /* Assign a stack slot in a containing function.
750 First three arguments are same as in preceding function.
751 The last argument specifies the function to allocate in. */
754 assign_outer_stack_local (mode, size, align, function)
755 enum machine_mode mode;
758 struct function *function;
760 register rtx x, addr;
761 int bigend_correction = 0;
764 /* Allocate in the memory associated with the function in whose frame
766 push_obstacks (function->function_obstack,
767 function->function_maybepermanent_obstack);
771 alignment = GET_MODE_ALIGNMENT (mode) / BITS_PER_UNIT;
773 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
775 else if (align == -1)
777 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
778 size = CEIL_ROUND (size, alignment);
781 alignment = align / BITS_PER_UNIT;
783 /* Round frame offset to that alignment. */
784 #ifdef FRAME_GROWS_DOWNWARD
785 function->frame_offset = FLOOR_ROUND (function->frame_offset, alignment);
787 function->frame_offset = CEIL_ROUND (function->frame_offset, alignment);
790 /* On a big-endian machine, if we are allocating more space than we will use,
791 use the least significant bytes of those that are allocated. */
792 if (BYTES_BIG_ENDIAN && mode != BLKmode)
793 bigend_correction = size - GET_MODE_SIZE (mode);
795 #ifdef FRAME_GROWS_DOWNWARD
796 function->frame_offset -= size;
798 addr = plus_constant (virtual_stack_vars_rtx,
799 function->frame_offset + bigend_correction);
800 #ifndef FRAME_GROWS_DOWNWARD
801 function->frame_offset += size;
804 x = gen_rtx_MEM (mode, addr);
806 function->stack_slot_list
807 = gen_rtx_EXPR_LIST (VOIDmode, x, function->stack_slot_list);
814 /* Allocate a temporary stack slot and record it for possible later
817 MODE is the machine mode to be given to the returned rtx.
819 SIZE is the size in units of the space required. We do no rounding here
820 since assign_stack_local will do any required rounding.
822 KEEP is 1 if this slot is to be retained after a call to
823 free_temp_slots. Automatic variables for a block are allocated
824 with this flag. KEEP is 2 if we allocate a longer term temporary,
825 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
826 if we are to allocate something at an inner level to be treated as
827 a variable in the block (e.g., a SAVE_EXPR). */
830 assign_stack_temp (mode, size, keep)
831 enum machine_mode mode;
835 struct temp_slot *p, *best_p = 0;
837 /* If SIZE is -1 it means that somebody tried to allocate a temporary
838 of a variable size. */
842 /* First try to find an available, already-allocated temporary that is the
843 exact size we require. */
844 for (p = temp_slots; p; p = p->next)
845 if (p->size == size && GET_MODE (p->slot) == mode && ! p->in_use)
848 /* If we didn't find, one, try one that is larger than what we want. We
849 find the smallest such. */
851 for (p = temp_slots; p; p = p->next)
852 if (p->size > size && GET_MODE (p->slot) == mode && ! p->in_use
853 && (best_p == 0 || best_p->size > p->size))
856 /* Make our best, if any, the one to use. */
859 /* If there are enough aligned bytes left over, make them into a new
860 temp_slot so that the extra bytes don't get wasted. Do this only
861 for BLKmode slots, so that we can be sure of the alignment. */
862 if (GET_MODE (best_p->slot) == BLKmode)
864 int alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
865 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
867 if (best_p->size - rounded_size >= alignment)
869 p = (struct temp_slot *) oballoc (sizeof (struct temp_slot));
870 p->in_use = p->addr_taken = 0;
871 p->size = best_p->size - rounded_size;
872 p->base_offset = best_p->base_offset + rounded_size;
873 p->full_size = best_p->full_size - rounded_size;
874 p->slot = gen_rtx_MEM (BLKmode,
875 plus_constant (XEXP (best_p->slot, 0),
879 p->next = temp_slots;
882 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
885 best_p->size = rounded_size;
886 best_p->full_size = rounded_size;
893 /* If we still didn't find one, make a new temporary. */
896 HOST_WIDE_INT frame_offset_old = frame_offset;
898 p = (struct temp_slot *) oballoc (sizeof (struct temp_slot));
900 /* If the temp slot mode doesn't indicate the alignment,
901 use the largest possible, so no one will be disappointed. */
902 p->slot = assign_stack_local (mode, size, mode == BLKmode ? -1 : 0);
904 /* The following slot size computation is necessary because we don't
905 know the actual size of the temporary slot until assign_stack_local
906 has performed all the frame alignment and size rounding for the
907 requested temporary. Note that extra space added for alignment
908 can be either above or below this stack slot depending on which
909 way the frame grows. We include the extra space if and only if it
910 is above this slot. */
911 #ifdef FRAME_GROWS_DOWNWARD
912 p->size = frame_offset_old - frame_offset;
917 /* Now define the fields used by combine_temp_slots. */
918 #ifdef FRAME_GROWS_DOWNWARD
919 p->base_offset = frame_offset;
920 p->full_size = frame_offset_old - frame_offset;
922 p->base_offset = frame_offset_old;
923 p->full_size = frame_offset - frame_offset_old;
926 p->next = temp_slots;
932 p->rtl_expr = sequence_rtl_expr;
936 p->level = target_temp_slot_level;
941 p->level = var_temp_slot_level;
946 p->level = temp_slot_level;
950 /* We may be reusing an old slot, so clear any MEM flags that may have been
952 RTX_UNCHANGING_P (p->slot) = 0;
953 MEM_IN_STRUCT_P (p->slot) = 0;
957 /* Assign a temporary of given TYPE.
958 KEEP is as for assign_stack_temp.
959 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
960 it is 0 if a register is OK.
961 DONT_PROMOTE is 1 if we should not promote values in register
965 assign_temp (type, keep, memory_required, dont_promote)
971 enum machine_mode mode = TYPE_MODE (type);
972 int unsignedp = TREE_UNSIGNED (type);
974 if (mode == BLKmode || memory_required)
976 HOST_WIDE_INT size = int_size_in_bytes (type);
979 /* Unfortunately, we don't yet know how to allocate variable-sized
980 temporaries. However, sometimes we have a fixed upper limit on
981 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
982 instead. This is the case for Chill variable-sized strings. */
983 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
984 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
985 && TREE_CODE (TYPE_ARRAY_MAX_SIZE (type)) == INTEGER_CST)
986 size = TREE_INT_CST_LOW (TYPE_ARRAY_MAX_SIZE (type));
988 tmp = assign_stack_temp (mode, size, keep);
989 MEM_IN_STRUCT_P (tmp) = AGGREGATE_TYPE_P (type);
993 #ifndef PROMOTE_FOR_CALL_ONLY
995 mode = promote_mode (type, mode, &unsignedp, 0);
998 return gen_reg_rtx (mode);
1001 /* Combine temporary stack slots which are adjacent on the stack.
1003 This allows for better use of already allocated stack space. This is only
1004 done for BLKmode slots because we can be sure that we won't have alignment
1005 problems in this case. */
1008 combine_temp_slots ()
1010 struct temp_slot *p, *q;
1011 struct temp_slot *prev_p, *prev_q;
1014 /* If there are a lot of temp slots, don't do anything unless
1015 high levels of optimizaton. */
1016 if (! flag_expensive_optimizations)
1017 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
1018 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
1021 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
1025 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
1026 for (q = p->next, prev_q = p; q; q = prev_q->next)
1029 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
1031 if (p->base_offset + p->full_size == q->base_offset)
1033 /* Q comes after P; combine Q into P. */
1035 p->full_size += q->full_size;
1038 else if (q->base_offset + q->full_size == p->base_offset)
1040 /* P comes after Q; combine P into Q. */
1042 q->full_size += p->full_size;
1047 /* Either delete Q or advance past it. */
1049 prev_q->next = q->next;
1053 /* Either delete P or advance past it. */
1057 prev_p->next = p->next;
1059 temp_slots = p->next;
1066 /* Find the temp slot corresponding to the object at address X. */
1068 static struct temp_slot *
1069 find_temp_slot_from_address (x)
1072 struct temp_slot *p;
1075 for (p = temp_slots; p; p = p->next)
1080 else if (XEXP (p->slot, 0) == x
1082 || (GET_CODE (x) == PLUS
1083 && XEXP (x, 0) == virtual_stack_vars_rtx
1084 && GET_CODE (XEXP (x, 1)) == CONST_INT
1085 && INTVAL (XEXP (x, 1)) >= p->base_offset
1086 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
1089 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
1090 for (next = p->address; next; next = XEXP (next, 1))
1091 if (XEXP (next, 0) == x)
1098 /* Indicate that NEW is an alternate way of referring to the temp slot
1099 that previously was known by OLD. */
1102 update_temp_slot_address (old, new)
1105 struct temp_slot *p = find_temp_slot_from_address (old);
1107 /* If none, return. Else add NEW as an alias. */
1110 else if (p->address == 0)
1114 if (GET_CODE (p->address) != EXPR_LIST)
1115 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1117 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1121 /* If X could be a reference to a temporary slot, mark the fact that its
1122 address was taken. */
1125 mark_temp_addr_taken (x)
1128 struct temp_slot *p;
1133 /* If X is not in memory or is at a constant address, it cannot be in
1134 a temporary slot. */
1135 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1138 p = find_temp_slot_from_address (XEXP (x, 0));
1143 /* If X could be a reference to a temporary slot, mark that slot as
1144 belonging to the to one level higher than the current level. If X
1145 matched one of our slots, just mark that one. Otherwise, we can't
1146 easily predict which it is, so upgrade all of them. Kept slots
1147 need not be touched.
1149 This is called when an ({...}) construct occurs and a statement
1150 returns a value in memory. */
1153 preserve_temp_slots (x)
1156 struct temp_slot *p = 0;
1158 /* If there is no result, we still might have some objects whose address
1159 were taken, so we need to make sure they stay around. */
1162 for (p = temp_slots; p; p = p->next)
1163 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1169 /* If X is a register that is being used as a pointer, see if we have
1170 a temporary slot we know it points to. To be consistent with
1171 the code below, we really should preserve all non-kept slots
1172 if we can't find a match, but that seems to be much too costly. */
1173 if (GET_CODE (x) == REG && REGNO_POINTER_FLAG (REGNO (x)))
1174 p = find_temp_slot_from_address (x);
1176 /* If X is not in memory or is at a constant address, it cannot be in
1177 a temporary slot, but it can contain something whose address was
1179 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1181 for (p = temp_slots; p; p = p->next)
1182 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1188 /* First see if we can find a match. */
1190 p = find_temp_slot_from_address (XEXP (x, 0));
1194 /* Move everything at our level whose address was taken to our new
1195 level in case we used its address. */
1196 struct temp_slot *q;
1198 if (p->level == temp_slot_level)
1200 for (q = temp_slots; q; q = q->next)
1201 if (q != p && q->addr_taken && q->level == p->level)
1210 /* Otherwise, preserve all non-kept slots at this level. */
1211 for (p = temp_slots; p; p = p->next)
1212 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1216 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1217 with that RTL_EXPR, promote it into a temporary slot at the present
1218 level so it will not be freed when we free slots made in the
1222 preserve_rtl_expr_result (x)
1225 struct temp_slot *p;
1227 /* If X is not in memory or is at a constant address, it cannot be in
1228 a temporary slot. */
1229 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1232 /* If we can find a match, move it to our level unless it is already at
1234 p = find_temp_slot_from_address (XEXP (x, 0));
1237 p->level = MIN (p->level, temp_slot_level);
1244 /* Free all temporaries used so far. This is normally called at the end
1245 of generating code for a statement. Don't free any temporaries
1246 currently in use for an RTL_EXPR that hasn't yet been emitted.
1247 We could eventually do better than this since it can be reused while
1248 generating the same RTL_EXPR, but this is complex and probably not
1254 struct temp_slot *p;
1256 for (p = temp_slots; p; p = p->next)
1257 if (p->in_use && p->level == temp_slot_level && ! p->keep
1258 && p->rtl_expr == 0)
1261 combine_temp_slots ();
1264 /* Free all temporary slots used in T, an RTL_EXPR node. */
1267 free_temps_for_rtl_expr (t)
1270 struct temp_slot *p;
1272 for (p = temp_slots; p; p = p->next)
1273 if (p->rtl_expr == t)
1276 combine_temp_slots ();
1279 /* Mark all temporaries ever allocated in this function as not suitable
1280 for reuse until the current level is exited. */
1283 mark_all_temps_used ()
1285 struct temp_slot *p;
1287 for (p = temp_slots; p; p = p->next)
1289 p->in_use = p->keep = 1;
1290 p->level = MIN (p->level, temp_slot_level);
1294 /* Push deeper into the nesting level for stack temporaries. */
1302 /* Likewise, but save the new level as the place to allocate variables
1306 push_temp_slots_for_block ()
1310 var_temp_slot_level = temp_slot_level;
1313 /* Likewise, but save the new level as the place to allocate temporaries
1314 for TARGET_EXPRs. */
1317 push_temp_slots_for_target ()
1321 target_temp_slot_level = temp_slot_level;
1324 /* Set and get the value of target_temp_slot_level. The only
1325 permitted use of these functions is to save and restore this value. */
1328 get_target_temp_slot_level ()
1330 return target_temp_slot_level;
1334 set_target_temp_slot_level (level)
1337 target_temp_slot_level = level;
1340 /* Pop a temporary nesting level. All slots in use in the current level
1346 struct temp_slot *p;
1348 for (p = temp_slots; p; p = p->next)
1349 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1352 combine_temp_slots ();
1357 /* Initialize temporary slots. */
1362 /* We have not allocated any temporaries yet. */
1364 temp_slot_level = 0;
1365 var_temp_slot_level = 0;
1366 target_temp_slot_level = 0;
1369 /* Retroactively move an auto variable from a register to a stack slot.
1370 This is done when an address-reference to the variable is seen. */
1373 put_var_into_stack (decl)
1377 enum machine_mode promoted_mode, decl_mode;
1378 struct function *function = 0;
1380 int can_use_addressof;
1382 context = decl_function_context (decl);
1384 /* Get the current rtl used for this object and its original mode. */
1385 reg = TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl) : DECL_RTL (decl);
1387 /* No need to do anything if decl has no rtx yet
1388 since in that case caller is setting TREE_ADDRESSABLE
1389 and a stack slot will be assigned when the rtl is made. */
1393 /* Get the declared mode for this object. */
1394 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1395 : DECL_MODE (decl));
1396 /* Get the mode it's actually stored in. */
1397 promoted_mode = GET_MODE (reg);
1399 /* If this variable comes from an outer function,
1400 find that function's saved context. */
1401 if (context != current_function_decl && context != inline_function_decl)
1402 for (function = outer_function_chain; function; function = function->next)
1403 if (function->decl == context)
1406 /* If this is a variable-size object with a pseudo to address it,
1407 put that pseudo into the stack, if the var is nonlocal. */
1408 if (DECL_NONLOCAL (decl)
1409 && GET_CODE (reg) == MEM
1410 && GET_CODE (XEXP (reg, 0)) == REG
1411 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1413 reg = XEXP (reg, 0);
1414 decl_mode = promoted_mode = GET_MODE (reg);
1420 /* FIXME make it work for promoted modes too */
1421 && decl_mode == promoted_mode
1422 #ifdef NON_SAVING_SETJMP
1423 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1427 /* If we can't use ADDRESSOF, make sure we see through one we already
1429 if (! can_use_addressof && GET_CODE (reg) == MEM
1430 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1431 reg = XEXP (XEXP (reg, 0), 0);
1433 /* Now we should have a value that resides in one or more pseudo regs. */
1435 if (GET_CODE (reg) == REG)
1437 /* If this variable lives in the current function and we don't need
1438 to put things in the stack for the sake of setjmp, try to keep it
1439 in a register until we know we actually need the address. */
1440 if (can_use_addressof)
1441 gen_mem_addressof (reg, decl);
1443 put_reg_into_stack (function, reg, TREE_TYPE (decl),
1444 promoted_mode, decl_mode,
1445 TREE_SIDE_EFFECTS (decl), 0,
1447 || DECL_INITIAL (decl) != 0);
1449 else if (GET_CODE (reg) == CONCAT)
1451 /* A CONCAT contains two pseudos; put them both in the stack.
1452 We do it so they end up consecutive. */
1453 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1454 tree part_type = TREE_TYPE (TREE_TYPE (decl));
1455 #ifdef FRAME_GROWS_DOWNWARD
1456 /* Since part 0 should have a lower address, do it second. */
1457 put_reg_into_stack (function, XEXP (reg, 1), part_type, part_mode,
1458 part_mode, TREE_SIDE_EFFECTS (decl), 0,
1459 TREE_USED (decl) || DECL_INITIAL (decl) != 0);
1460 put_reg_into_stack (function, XEXP (reg, 0), part_type, part_mode,
1461 part_mode, TREE_SIDE_EFFECTS (decl), 0,
1462 TREE_USED (decl) || DECL_INITIAL (decl) != 0);
1464 put_reg_into_stack (function, XEXP (reg, 0), part_type, part_mode,
1465 part_mode, TREE_SIDE_EFFECTS (decl), 0,
1466 TREE_USED (decl) || DECL_INITIAL (decl) != 0);
1467 put_reg_into_stack (function, XEXP (reg, 1), part_type, part_mode,
1468 part_mode, TREE_SIDE_EFFECTS (decl), 0,
1469 TREE_USED (decl) || DECL_INITIAL (decl) != 0);
1472 /* Change the CONCAT into a combined MEM for both parts. */
1473 PUT_CODE (reg, MEM);
1474 MEM_VOLATILE_P (reg) = MEM_VOLATILE_P (XEXP (reg, 0));
1475 MEM_ALIAS_SET (reg) = get_alias_set (decl);
1477 /* The two parts are in memory order already.
1478 Use the lower parts address as ours. */
1479 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1480 /* Prevent sharing of rtl that might lose. */
1481 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1482 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1487 if (flag_check_memory_usage)
1488 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
1489 XEXP (reg, 0), ptr_mode,
1490 GEN_INT (GET_MODE_SIZE (GET_MODE (reg))),
1491 TYPE_MODE (sizetype),
1492 GEN_INT (MEMORY_USE_RW),
1493 TYPE_MODE (integer_type_node));
1496 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1497 into the stack frame of FUNCTION (0 means the current function).
1498 DECL_MODE is the machine mode of the user-level data type.
1499 PROMOTED_MODE is the machine mode of the register.
1500 VOLATILE_P is nonzero if this is for a "volatile" decl.
1501 USED_P is nonzero if this reg might have already been used in an insn. */
1504 put_reg_into_stack (function, reg, type, promoted_mode, decl_mode, volatile_p,
1505 original_regno, used_p)
1506 struct function *function;
1509 enum machine_mode promoted_mode, decl_mode;
1515 int regno = original_regno;
1518 regno = REGNO (reg);
1522 if (regno < function->max_parm_reg)
1523 new = function->parm_reg_stack_loc[regno];
1525 new = assign_outer_stack_local (decl_mode, GET_MODE_SIZE (decl_mode),
1530 if (regno < max_parm_reg)
1531 new = parm_reg_stack_loc[regno];
1533 new = assign_stack_local (decl_mode, GET_MODE_SIZE (decl_mode), 0);
1536 PUT_MODE (reg, decl_mode);
1537 XEXP (reg, 0) = XEXP (new, 0);
1538 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1539 MEM_VOLATILE_P (reg) = volatile_p;
1540 PUT_CODE (reg, MEM);
1542 /* If this is a memory ref that contains aggregate components,
1543 mark it as such for cse and loop optimize. If we are reusing a
1544 previously generated stack slot, then we need to copy the bit in
1545 case it was set for other reasons. For instance, it is set for
1546 __builtin_va_alist. */
1547 MEM_IN_STRUCT_P (reg) = AGGREGATE_TYPE_P (type) | MEM_IN_STRUCT_P (new);
1548 MEM_ALIAS_SET (reg) = get_alias_set (type);
1550 /* Now make sure that all refs to the variable, previously made
1551 when it was a register, are fixed up to be valid again. */
1553 if (used_p && function != 0)
1555 struct var_refs_queue *temp;
1557 /* Variable is inherited; fix it up when we get back to its function. */
1558 push_obstacks (function->function_obstack,
1559 function->function_maybepermanent_obstack);
1561 /* See comment in restore_tree_status in tree.c for why this needs to be
1562 on saveable obstack. */
1564 = (struct var_refs_queue *) savealloc (sizeof (struct var_refs_queue));
1565 temp->modified = reg;
1566 temp->promoted_mode = promoted_mode;
1567 temp->unsignedp = TREE_UNSIGNED (type);
1568 temp->next = function->fixup_var_refs_queue;
1569 function->fixup_var_refs_queue = temp;
1573 /* Variable is local; fix it up now. */
1574 fixup_var_refs (reg, promoted_mode, TREE_UNSIGNED (type));
1578 fixup_var_refs (var, promoted_mode, unsignedp)
1580 enum machine_mode promoted_mode;
1584 rtx first_insn = get_insns ();
1585 struct sequence_stack *stack = sequence_stack;
1586 tree rtl_exps = rtl_expr_chain;
1588 /* Must scan all insns for stack-refs that exceed the limit. */
1589 fixup_var_refs_insns (var, promoted_mode, unsignedp, first_insn, stack == 0);
1591 /* Scan all pending sequences too. */
1592 for (; stack; stack = stack->next)
1594 push_to_sequence (stack->first);
1595 fixup_var_refs_insns (var, promoted_mode, unsignedp,
1596 stack->first, stack->next != 0);
1597 /* Update remembered end of sequence
1598 in case we added an insn at the end. */
1599 stack->last = get_last_insn ();
1603 /* Scan all waiting RTL_EXPRs too. */
1604 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1606 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1607 if (seq != const0_rtx && seq != 0)
1609 push_to_sequence (seq);
1610 fixup_var_refs_insns (var, promoted_mode, unsignedp, seq, 0);
1616 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1617 some part of an insn. Return a struct fixup_replacement whose OLD
1618 value is equal to X. Allocate a new structure if no such entry exists. */
1620 static struct fixup_replacement *
1621 find_fixup_replacement (replacements, x)
1622 struct fixup_replacement **replacements;
1625 struct fixup_replacement *p;
1627 /* See if we have already replaced this. */
1628 for (p = *replacements; p && p->old != x; p = p->next)
1633 p = (struct fixup_replacement *) oballoc (sizeof (struct fixup_replacement));
1636 p->next = *replacements;
1643 /* Scan the insn-chain starting with INSN for refs to VAR
1644 and fix them up. TOPLEVEL is nonzero if this chain is the
1645 main chain of insns for the current function. */
1648 fixup_var_refs_insns (var, promoted_mode, unsignedp, insn, toplevel)
1650 enum machine_mode promoted_mode;
1659 rtx next = NEXT_INSN (insn);
1660 rtx set, prev, prev_set;
1663 if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
1665 /* If this is a CLOBBER of VAR, delete it.
1667 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1668 and REG_RETVAL notes too. */
1669 if (GET_CODE (PATTERN (insn)) == CLOBBER
1670 && (XEXP (PATTERN (insn), 0) == var
1671 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1672 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1673 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1675 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1676 /* The REG_LIBCALL note will go away since we are going to
1677 turn INSN into a NOTE, so just delete the
1678 corresponding REG_RETVAL note. */
1679 remove_note (XEXP (note, 0),
1680 find_reg_note (XEXP (note, 0), REG_RETVAL,
1683 /* In unoptimized compilation, we shouldn't call delete_insn
1684 except in jump.c doing warnings. */
1685 PUT_CODE (insn, NOTE);
1686 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1687 NOTE_SOURCE_FILE (insn) = 0;
1690 /* The insn to load VAR from a home in the arglist
1691 is now a no-op. When we see it, just delete it.
1692 Similarly if this is storing VAR from a register from which
1693 it was loaded in the previous insn. This will occur
1694 when an ADDRESSOF was made for an arglist slot. */
1696 && (set = single_set (insn)) != 0
1697 && SET_DEST (set) == var
1698 /* If this represents the result of an insn group,
1699 don't delete the insn. */
1700 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1701 && (rtx_equal_p (SET_SRC (set), var)
1702 || (GET_CODE (SET_SRC (set)) == REG
1703 && (prev = prev_nonnote_insn (insn)) != 0
1704 && (prev_set = single_set (prev)) != 0
1705 && SET_DEST (prev_set) == SET_SRC (set)
1706 && rtx_equal_p (SET_SRC (prev_set), var))))
1708 /* In unoptimized compilation, we shouldn't call delete_insn
1709 except in jump.c doing warnings. */
1710 PUT_CODE (insn, NOTE);
1711 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1712 NOTE_SOURCE_FILE (insn) = 0;
1713 if (insn == last_parm_insn)
1714 last_parm_insn = PREV_INSN (next);
1718 struct fixup_replacement *replacements = 0;
1719 rtx next_insn = NEXT_INSN (insn);
1721 if (SMALL_REGISTER_CLASSES)
1723 /* If the insn that copies the results of a CALL_INSN
1724 into a pseudo now references VAR, we have to use an
1725 intermediate pseudo since we want the life of the
1726 return value register to be only a single insn.
1728 If we don't use an intermediate pseudo, such things as
1729 address computations to make the address of VAR valid
1730 if it is not can be placed between the CALL_INSN and INSN.
1732 To make sure this doesn't happen, we record the destination
1733 of the CALL_INSN and see if the next insn uses both that
1736 if (call_dest != 0 && GET_CODE (insn) == INSN
1737 && reg_mentioned_p (var, PATTERN (insn))
1738 && reg_mentioned_p (call_dest, PATTERN (insn)))
1740 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1742 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1744 PATTERN (insn) = replace_rtx (PATTERN (insn),
1748 if (GET_CODE (insn) == CALL_INSN
1749 && GET_CODE (PATTERN (insn)) == SET)
1750 call_dest = SET_DEST (PATTERN (insn));
1751 else if (GET_CODE (insn) == CALL_INSN
1752 && GET_CODE (PATTERN (insn)) == PARALLEL
1753 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1754 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1759 /* See if we have to do anything to INSN now that VAR is in
1760 memory. If it needs to be loaded into a pseudo, use a single
1761 pseudo for the entire insn in case there is a MATCH_DUP
1762 between two operands. We pass a pointer to the head of
1763 a list of struct fixup_replacements. If fixup_var_refs_1
1764 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1765 it will record them in this list.
1767 If it allocated a pseudo for any replacement, we copy into
1770 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1773 /* If this is last_parm_insn, and any instructions were output
1774 after it to fix it up, then we must set last_parm_insn to
1775 the last such instruction emitted. */
1776 if (insn == last_parm_insn)
1777 last_parm_insn = PREV_INSN (next_insn);
1779 while (replacements)
1781 if (GET_CODE (replacements->new) == REG)
1786 /* OLD might be a (subreg (mem)). */
1787 if (GET_CODE (replacements->old) == SUBREG)
1789 = fixup_memory_subreg (replacements->old, insn, 0);
1792 = fixup_stack_1 (replacements->old, insn);
1794 insert_before = insn;
1796 /* If we are changing the mode, do a conversion.
1797 This might be wasteful, but combine.c will
1798 eliminate much of the waste. */
1800 if (GET_MODE (replacements->new)
1801 != GET_MODE (replacements->old))
1804 convert_move (replacements->new,
1805 replacements->old, unsignedp);
1806 seq = gen_sequence ();
1810 seq = gen_move_insn (replacements->new,
1813 emit_insn_before (seq, insert_before);
1816 replacements = replacements->next;
1820 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1821 But don't touch other insns referred to by reg-notes;
1822 we will get them elsewhere. */
1823 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
1824 if (GET_CODE (note) != INSN_LIST)
1826 = walk_fixup_memory_subreg (XEXP (note, 0), insn, 1);
1832 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1833 See if the rtx expression at *LOC in INSN needs to be changed.
1835 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1836 contain a list of original rtx's and replacements. If we find that we need
1837 to modify this insn by replacing a memory reference with a pseudo or by
1838 making a new MEM to implement a SUBREG, we consult that list to see if
1839 we have already chosen a replacement. If none has already been allocated,
1840 we allocate it and update the list. fixup_var_refs_insns will copy VAR
1841 or the SUBREG, as appropriate, to the pseudo. */
1844 fixup_var_refs_1 (var, promoted_mode, loc, insn, replacements)
1846 enum machine_mode promoted_mode;
1849 struct fixup_replacement **replacements;
1852 register rtx x = *loc;
1853 RTX_CODE code = GET_CODE (x);
1855 register rtx tem, tem1;
1856 struct fixup_replacement *replacement;
1861 if (XEXP (x, 0) == var)
1863 /* Prevent sharing of rtl that might lose. */
1864 rtx sub = copy_rtx (XEXP (var, 0));
1868 if (! validate_change (insn, loc, sub, 0))
1870 rtx y = force_operand (sub, NULL_RTX);
1872 if (! validate_change (insn, loc, y, 0))
1873 *loc = copy_to_reg (y);
1876 emit_insn_before (gen_sequence (), insn);
1884 /* If we already have a replacement, use it. Otherwise,
1885 try to fix up this address in case it is invalid. */
1887 replacement = find_fixup_replacement (replacements, var);
1888 if (replacement->new)
1890 *loc = replacement->new;
1894 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1896 /* Unless we are forcing memory to register or we changed the mode,
1897 we can leave things the way they are if the insn is valid. */
1899 INSN_CODE (insn) = -1;
1900 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1901 && recog_memoized (insn) >= 0)
1904 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1908 /* If X contains VAR, we need to unshare it here so that we update
1909 each occurrence separately. But all identical MEMs in one insn
1910 must be replaced with the same rtx because of the possibility of
1913 if (reg_mentioned_p (var, x))
1915 replacement = find_fixup_replacement (replacements, x);
1916 if (replacement->new == 0)
1917 replacement->new = copy_most_rtx (x, var);
1919 *loc = x = replacement->new;
1935 /* Note that in some cases those types of expressions are altered
1936 by optimize_bit_field, and do not survive to get here. */
1937 if (XEXP (x, 0) == var
1938 || (GET_CODE (XEXP (x, 0)) == SUBREG
1939 && SUBREG_REG (XEXP (x, 0)) == var))
1941 /* Get TEM as a valid MEM in the mode presently in the insn.
1943 We don't worry about the possibility of MATCH_DUP here; it
1944 is highly unlikely and would be tricky to handle. */
1947 if (GET_CODE (tem) == SUBREG)
1949 if (GET_MODE_BITSIZE (GET_MODE (tem))
1950 > GET_MODE_BITSIZE (GET_MODE (var)))
1952 replacement = find_fixup_replacement (replacements, var);
1953 if (replacement->new == 0)
1954 replacement->new = gen_reg_rtx (GET_MODE (var));
1955 SUBREG_REG (tem) = replacement->new;
1958 tem = fixup_memory_subreg (tem, insn, 0);
1961 tem = fixup_stack_1 (tem, insn);
1963 /* Unless we want to load from memory, get TEM into the proper mode
1964 for an extract from memory. This can only be done if the
1965 extract is at a constant position and length. */
1967 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
1968 && GET_CODE (XEXP (x, 2)) == CONST_INT
1969 && ! mode_dependent_address_p (XEXP (tem, 0))
1970 && ! MEM_VOLATILE_P (tem))
1972 enum machine_mode wanted_mode = VOIDmode;
1973 enum machine_mode is_mode = GET_MODE (tem);
1974 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
1977 if (GET_CODE (x) == ZERO_EXTRACT)
1979 wanted_mode = insn_operand_mode[(int) CODE_FOR_extzv][1];
1980 if (wanted_mode == VOIDmode)
1981 wanted_mode = word_mode;
1985 if (GET_CODE (x) == SIGN_EXTRACT)
1987 wanted_mode = insn_operand_mode[(int) CODE_FOR_extv][1];
1988 if (wanted_mode == VOIDmode)
1989 wanted_mode = word_mode;
1992 /* If we have a narrower mode, we can do something. */
1993 if (wanted_mode != VOIDmode
1994 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
1996 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
1997 rtx old_pos = XEXP (x, 2);
2000 /* If the bytes and bits are counted differently, we
2001 must adjust the offset. */
2002 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2003 offset = (GET_MODE_SIZE (is_mode)
2004 - GET_MODE_SIZE (wanted_mode) - offset);
2006 pos %= GET_MODE_BITSIZE (wanted_mode);
2008 newmem = gen_rtx_MEM (wanted_mode,
2009 plus_constant (XEXP (tem, 0), offset));
2010 RTX_UNCHANGING_P (newmem) = RTX_UNCHANGING_P (tem);
2011 MEM_VOLATILE_P (newmem) = MEM_VOLATILE_P (tem);
2012 MEM_IN_STRUCT_P (newmem) = MEM_IN_STRUCT_P (tem);
2014 /* Make the change and see if the insn remains valid. */
2015 INSN_CODE (insn) = -1;
2016 XEXP (x, 0) = newmem;
2017 XEXP (x, 2) = GEN_INT (pos);
2019 if (recog_memoized (insn) >= 0)
2022 /* Otherwise, restore old position. XEXP (x, 0) will be
2024 XEXP (x, 2) = old_pos;
2028 /* If we get here, the bitfield extract insn can't accept a memory
2029 reference. Copy the input into a register. */
2031 tem1 = gen_reg_rtx (GET_MODE (tem));
2032 emit_insn_before (gen_move_insn (tem1, tem), insn);
2039 if (SUBREG_REG (x) == var)
2041 /* If this is a special SUBREG made because VAR was promoted
2042 from a wider mode, replace it with VAR and call ourself
2043 recursively, this time saying that the object previously
2044 had its current mode (by virtue of the SUBREG). */
2046 if (SUBREG_PROMOTED_VAR_P (x))
2049 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements);
2053 /* If this SUBREG makes VAR wider, it has become a paradoxical
2054 SUBREG with VAR in memory, but these aren't allowed at this
2055 stage of the compilation. So load VAR into a pseudo and take
2056 a SUBREG of that pseudo. */
2057 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2059 replacement = find_fixup_replacement (replacements, var);
2060 if (replacement->new == 0)
2061 replacement->new = gen_reg_rtx (GET_MODE (var));
2062 SUBREG_REG (x) = replacement->new;
2066 /* See if we have already found a replacement for this SUBREG.
2067 If so, use it. Otherwise, make a MEM and see if the insn
2068 is recognized. If not, or if we should force MEM into a register,
2069 make a pseudo for this SUBREG. */
2070 replacement = find_fixup_replacement (replacements, x);
2071 if (replacement->new)
2073 *loc = replacement->new;
2077 replacement->new = *loc = fixup_memory_subreg (x, insn, 0);
2079 INSN_CODE (insn) = -1;
2080 if (! flag_force_mem && recog_memoized (insn) >= 0)
2083 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2089 /* First do special simplification of bit-field references. */
2090 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2091 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2092 optimize_bit_field (x, insn, 0);
2093 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2094 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2095 optimize_bit_field (x, insn, NULL_PTR);
2097 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2098 into a register and then store it back out. */
2099 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2100 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2101 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2102 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2103 > GET_MODE_SIZE (GET_MODE (var))))
2105 replacement = find_fixup_replacement (replacements, var);
2106 if (replacement->new == 0)
2107 replacement->new = gen_reg_rtx (GET_MODE (var));
2109 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2110 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2113 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2114 insn into a pseudo and store the low part of the pseudo into VAR. */
2115 if (GET_CODE (SET_DEST (x)) == SUBREG
2116 && SUBREG_REG (SET_DEST (x)) == var
2117 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2118 > GET_MODE_SIZE (GET_MODE (var))))
2120 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2121 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2128 rtx dest = SET_DEST (x);
2129 rtx src = SET_SRC (x);
2131 rtx outerdest = dest;
2134 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2135 || GET_CODE (dest) == SIGN_EXTRACT
2136 || GET_CODE (dest) == ZERO_EXTRACT)
2137 dest = XEXP (dest, 0);
2139 if (GET_CODE (src) == SUBREG)
2140 src = XEXP (src, 0);
2142 /* If VAR does not appear at the top level of the SET
2143 just scan the lower levels of the tree. */
2145 if (src != var && dest != var)
2148 /* We will need to rerecognize this insn. */
2149 INSN_CODE (insn) = -1;
2152 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var)
2154 /* Since this case will return, ensure we fixup all the
2156 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2157 insn, replacements);
2158 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2159 insn, replacements);
2160 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2161 insn, replacements);
2163 tem = XEXP (outerdest, 0);
2165 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2166 that may appear inside a ZERO_EXTRACT.
2167 This was legitimate when the MEM was a REG. */
2168 if (GET_CODE (tem) == SUBREG
2169 && SUBREG_REG (tem) == var)
2170 tem = fixup_memory_subreg (tem, insn, 0);
2172 tem = fixup_stack_1 (tem, insn);
2174 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2175 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2176 && ! mode_dependent_address_p (XEXP (tem, 0))
2177 && ! MEM_VOLATILE_P (tem))
2179 enum machine_mode wanted_mode;
2180 enum machine_mode is_mode = GET_MODE (tem);
2181 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2183 wanted_mode = insn_operand_mode[(int) CODE_FOR_insv][0];
2184 if (wanted_mode == VOIDmode)
2185 wanted_mode = word_mode;
2187 /* If we have a narrower mode, we can do something. */
2188 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2190 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2191 rtx old_pos = XEXP (outerdest, 2);
2194 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2195 offset = (GET_MODE_SIZE (is_mode)
2196 - GET_MODE_SIZE (wanted_mode) - offset);
2198 pos %= GET_MODE_BITSIZE (wanted_mode);
2200 newmem = gen_rtx_MEM (wanted_mode,
2201 plus_constant (XEXP (tem, 0), offset));
2202 RTX_UNCHANGING_P (newmem) = RTX_UNCHANGING_P (tem);
2203 MEM_VOLATILE_P (newmem) = MEM_VOLATILE_P (tem);
2204 MEM_IN_STRUCT_P (newmem) = MEM_IN_STRUCT_P (tem);
2206 /* Make the change and see if the insn remains valid. */
2207 INSN_CODE (insn) = -1;
2208 XEXP (outerdest, 0) = newmem;
2209 XEXP (outerdest, 2) = GEN_INT (pos);
2211 if (recog_memoized (insn) >= 0)
2214 /* Otherwise, restore old position. XEXP (x, 0) will be
2216 XEXP (outerdest, 2) = old_pos;
2220 /* If we get here, the bit-field store doesn't allow memory
2221 or isn't located at a constant position. Load the value into
2222 a register, do the store, and put it back into memory. */
2224 tem1 = gen_reg_rtx (GET_MODE (tem));
2225 emit_insn_before (gen_move_insn (tem1, tem), insn);
2226 emit_insn_after (gen_move_insn (tem, tem1), insn);
2227 XEXP (outerdest, 0) = tem1;
2232 /* STRICT_LOW_PART is a no-op on memory references
2233 and it can cause combinations to be unrecognizable,
2236 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2237 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2239 /* A valid insn to copy VAR into or out of a register
2240 must be left alone, to avoid an infinite loop here.
2241 If the reference to VAR is by a subreg, fix that up,
2242 since SUBREG is not valid for a memref.
2243 Also fix up the address of the stack slot.
2245 Note that we must not try to recognize the insn until
2246 after we know that we have valid addresses and no
2247 (subreg (mem ...) ...) constructs, since these interfere
2248 with determining the validity of the insn. */
2250 if ((SET_SRC (x) == var
2251 || (GET_CODE (SET_SRC (x)) == SUBREG
2252 && SUBREG_REG (SET_SRC (x)) == var))
2253 && (GET_CODE (SET_DEST (x)) == REG
2254 || (GET_CODE (SET_DEST (x)) == SUBREG
2255 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2256 && GET_MODE (var) == promoted_mode
2257 && x == single_set (insn))
2261 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2262 if (replacement->new)
2263 SET_SRC (x) = replacement->new;
2264 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2265 SET_SRC (x) = replacement->new
2266 = fixup_memory_subreg (SET_SRC (x), insn, 0);
2268 SET_SRC (x) = replacement->new
2269 = fixup_stack_1 (SET_SRC (x), insn);
2271 if (recog_memoized (insn) >= 0)
2274 /* INSN is not valid, but we know that we want to
2275 copy SET_SRC (x) to SET_DEST (x) in some way. So
2276 we generate the move and see whether it requires more
2277 than one insn. If it does, we emit those insns and
2278 delete INSN. Otherwise, we an just replace the pattern
2279 of INSN; we have already verified above that INSN has
2280 no other function that to do X. */
2282 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2283 if (GET_CODE (pat) == SEQUENCE)
2285 emit_insn_after (pat, insn);
2286 PUT_CODE (insn, NOTE);
2287 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
2288 NOTE_SOURCE_FILE (insn) = 0;
2291 PATTERN (insn) = pat;
2296 if ((SET_DEST (x) == var
2297 || (GET_CODE (SET_DEST (x)) == SUBREG
2298 && SUBREG_REG (SET_DEST (x)) == var))
2299 && (GET_CODE (SET_SRC (x)) == REG
2300 || (GET_CODE (SET_SRC (x)) == SUBREG
2301 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2302 && GET_MODE (var) == promoted_mode
2303 && x == single_set (insn))
2307 if (GET_CODE (SET_DEST (x)) == SUBREG)
2308 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn, 0);
2310 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2312 if (recog_memoized (insn) >= 0)
2315 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2316 if (GET_CODE (pat) == SEQUENCE)
2318 emit_insn_after (pat, insn);
2319 PUT_CODE (insn, NOTE);
2320 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
2321 NOTE_SOURCE_FILE (insn) = 0;
2324 PATTERN (insn) = pat;
2329 /* Otherwise, storing into VAR must be handled specially
2330 by storing into a temporary and copying that into VAR
2331 with a new insn after this one. Note that this case
2332 will be used when storing into a promoted scalar since
2333 the insn will now have different modes on the input
2334 and output and hence will be invalid (except for the case
2335 of setting it to a constant, which does not need any
2336 change if it is valid). We generate extra code in that case,
2337 but combine.c will eliminate it. */
2342 rtx fixeddest = SET_DEST (x);
2344 /* STRICT_LOW_PART can be discarded, around a MEM. */
2345 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2346 fixeddest = XEXP (fixeddest, 0);
2347 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2348 if (GET_CODE (fixeddest) == SUBREG)
2350 fixeddest = fixup_memory_subreg (fixeddest, insn, 0);
2351 promoted_mode = GET_MODE (fixeddest);
2354 fixeddest = fixup_stack_1 (fixeddest, insn);
2356 temp = gen_reg_rtx (promoted_mode);
2358 emit_insn_after (gen_move_insn (fixeddest,
2359 gen_lowpart (GET_MODE (fixeddest),
2363 SET_DEST (x) = temp;
2371 /* Nothing special about this RTX; fix its operands. */
2373 fmt = GET_RTX_FORMAT (code);
2374 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2377 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements);
2381 for (j = 0; j < XVECLEN (x, i); j++)
2382 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2383 insn, replacements);
2388 /* Given X, an rtx of the form (SUBREG:m1 (MEM:m2 addr)),
2389 return an rtx (MEM:m1 newaddr) which is equivalent.
2390 If any insns must be emitted to compute NEWADDR, put them before INSN.
2392 UNCRITICAL nonzero means accept paradoxical subregs.
2393 This is used for subregs found inside REG_NOTES. */
2396 fixup_memory_subreg (x, insn, uncritical)
2401 int offset = SUBREG_WORD (x) * UNITS_PER_WORD;
2402 rtx addr = XEXP (SUBREG_REG (x), 0);
2403 enum machine_mode mode = GET_MODE (x);
2406 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2407 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))
2411 if (BYTES_BIG_ENDIAN)
2412 offset += (MIN (UNITS_PER_WORD, GET_MODE_SIZE (GET_MODE (SUBREG_REG (x))))
2413 - MIN (UNITS_PER_WORD, GET_MODE_SIZE (mode)));
2414 addr = plus_constant (addr, offset);
2415 if (!flag_force_addr && memory_address_p (mode, addr))
2416 /* Shortcut if no insns need be emitted. */
2417 return change_address (SUBREG_REG (x), mode, addr);
2419 result = change_address (SUBREG_REG (x), mode, addr);
2420 emit_insn_before (gen_sequence (), insn);
2425 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2426 Replace subexpressions of X in place.
2427 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2428 Otherwise return X, with its contents possibly altered.
2430 If any insns must be emitted to compute NEWADDR, put them before INSN.
2432 UNCRITICAL is as in fixup_memory_subreg. */
2435 walk_fixup_memory_subreg (x, insn, uncritical)
2440 register enum rtx_code code;
2447 code = GET_CODE (x);
2449 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2450 return fixup_memory_subreg (x, insn, uncritical);
2452 /* Nothing special about this RTX; fix its operands. */
2454 fmt = GET_RTX_FORMAT (code);
2455 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2458 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn, uncritical);
2462 for (j = 0; j < XVECLEN (x, i); j++)
2464 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn, uncritical);
2470 /* For each memory ref within X, if it refers to a stack slot
2471 with an out of range displacement, put the address in a temp register
2472 (emitting new insns before INSN to load these registers)
2473 and alter the memory ref to use that register.
2474 Replace each such MEM rtx with a copy, to avoid clobberage. */
2477 fixup_stack_1 (x, insn)
2482 register RTX_CODE code = GET_CODE (x);
2487 register rtx ad = XEXP (x, 0);
2488 /* If we have address of a stack slot but it's not valid
2489 (displacement is too large), compute the sum in a register. */
2490 if (GET_CODE (ad) == PLUS
2491 && GET_CODE (XEXP (ad, 0)) == REG
2492 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2493 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2494 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2495 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2496 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2498 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2499 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2500 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2501 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2504 if (memory_address_p (GET_MODE (x), ad))
2508 temp = copy_to_reg (ad);
2509 seq = gen_sequence ();
2511 emit_insn_before (seq, insn);
2512 return change_address (x, VOIDmode, temp);
2517 fmt = GET_RTX_FORMAT (code);
2518 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2521 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2525 for (j = 0; j < XVECLEN (x, i); j++)
2526 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2532 /* Optimization: a bit-field instruction whose field
2533 happens to be a byte or halfword in memory
2534 can be changed to a move instruction.
2536 We call here when INSN is an insn to examine or store into a bit-field.
2537 BODY is the SET-rtx to be altered.
2539 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2540 (Currently this is called only from function.c, and EQUIV_MEM
2544 optimize_bit_field (body, insn, equiv_mem)
2549 register rtx bitfield;
2552 enum machine_mode mode;
2554 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2555 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2556 bitfield = SET_DEST (body), destflag = 1;
2558 bitfield = SET_SRC (body), destflag = 0;
2560 /* First check that the field being stored has constant size and position
2561 and is in fact a byte or halfword suitably aligned. */
2563 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2564 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2565 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2567 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2569 register rtx memref = 0;
2571 /* Now check that the containing word is memory, not a register,
2572 and that it is safe to change the machine mode. */
2574 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2575 memref = XEXP (bitfield, 0);
2576 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2578 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2579 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2580 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2581 memref = SUBREG_REG (XEXP (bitfield, 0));
2582 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2584 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2585 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2588 && ! mode_dependent_address_p (XEXP (memref, 0))
2589 && ! MEM_VOLATILE_P (memref))
2591 /* Now adjust the address, first for any subreg'ing
2592 that we are now getting rid of,
2593 and then for which byte of the word is wanted. */
2595 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2598 /* Adjust OFFSET to count bits from low-address byte. */
2599 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2600 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2601 - offset - INTVAL (XEXP (bitfield, 1)));
2603 /* Adjust OFFSET to count bytes from low-address byte. */
2604 offset /= BITS_PER_UNIT;
2605 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2607 offset += SUBREG_WORD (XEXP (bitfield, 0)) * UNITS_PER_WORD;
2608 if (BYTES_BIG_ENDIAN)
2609 offset -= (MIN (UNITS_PER_WORD,
2610 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2611 - MIN (UNITS_PER_WORD,
2612 GET_MODE_SIZE (GET_MODE (memref))));
2616 memref = change_address (memref, mode,
2617 plus_constant (XEXP (memref, 0), offset));
2618 insns = get_insns ();
2620 emit_insns_before (insns, insn);
2622 /* Store this memory reference where
2623 we found the bit field reference. */
2627 validate_change (insn, &SET_DEST (body), memref, 1);
2628 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2630 rtx src = SET_SRC (body);
2631 while (GET_CODE (src) == SUBREG
2632 && SUBREG_WORD (src) == 0)
2633 src = SUBREG_REG (src);
2634 if (GET_MODE (src) != GET_MODE (memref))
2635 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2636 validate_change (insn, &SET_SRC (body), src, 1);
2638 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2639 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2640 /* This shouldn't happen because anything that didn't have
2641 one of these modes should have got converted explicitly
2642 and then referenced through a subreg.
2643 This is so because the original bit-field was
2644 handled by agg_mode and so its tree structure had
2645 the same mode that memref now has. */
2650 rtx dest = SET_DEST (body);
2652 while (GET_CODE (dest) == SUBREG
2653 && SUBREG_WORD (dest) == 0
2654 && (GET_MODE_CLASS (GET_MODE (dest))
2655 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest)))))
2656 dest = SUBREG_REG (dest);
2658 validate_change (insn, &SET_DEST (body), dest, 1);
2660 if (GET_MODE (dest) == GET_MODE (memref))
2661 validate_change (insn, &SET_SRC (body), memref, 1);
2664 /* Convert the mem ref to the destination mode. */
2665 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2668 convert_move (newreg, memref,
2669 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2673 validate_change (insn, &SET_SRC (body), newreg, 1);
2677 /* See if we can convert this extraction or insertion into
2678 a simple move insn. We might not be able to do so if this
2679 was, for example, part of a PARALLEL.
2681 If we succeed, write out any needed conversions. If we fail,
2682 it is hard to guess why we failed, so don't do anything
2683 special; just let the optimization be suppressed. */
2685 if (apply_change_group () && seq)
2686 emit_insns_before (seq, insn);
2691 /* These routines are responsible for converting virtual register references
2692 to the actual hard register references once RTL generation is complete.
2694 The following four variables are used for communication between the
2695 routines. They contain the offsets of the virtual registers from their
2696 respective hard registers. */
2698 static int in_arg_offset;
2699 static int var_offset;
2700 static int dynamic_offset;
2701 static int out_arg_offset;
2702 static int cfa_offset;
2704 /* In most machines, the stack pointer register is equivalent to the bottom
2707 #ifndef STACK_POINTER_OFFSET
2708 #define STACK_POINTER_OFFSET 0
2711 /* If not defined, pick an appropriate default for the offset of dynamically
2712 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2713 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2715 #ifndef STACK_DYNAMIC_OFFSET
2717 #ifdef ACCUMULATE_OUTGOING_ARGS
2718 /* The bottom of the stack points to the actual arguments. If
2719 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2720 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2721 stack space for register parameters is not pushed by the caller, but
2722 rather part of the fixed stack areas and hence not included in
2723 `current_function_outgoing_args_size'. Nevertheless, we must allow
2724 for it when allocating stack dynamic objects. */
2726 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2727 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2728 (current_function_outgoing_args_size \
2729 + REG_PARM_STACK_SPACE (FNDECL) + (STACK_POINTER_OFFSET))
2732 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2733 (current_function_outgoing_args_size + (STACK_POINTER_OFFSET))
2737 #define STACK_DYNAMIC_OFFSET(FNDECL) STACK_POINTER_OFFSET
2741 /* On a few machines, the CFA coincides with the arg pointer. */
2743 #ifndef ARG_POINTER_CFA_OFFSET
2744 #define ARG_POINTER_CFA_OFFSET 0
2748 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just had
2749 its address taken. DECL is the decl for the object stored in the
2750 register, for later use if we do need to force REG into the stack.
2751 REG is overwritten by the MEM like in put_reg_into_stack. */
2754 gen_mem_addressof (reg, decl)
2758 tree type = TREE_TYPE (decl);
2759 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)), REGNO (reg));
2760 SET_ADDRESSOF_DECL (r, decl);
2761 /* If the original REG was a user-variable, then so is the REG whose
2762 address is being taken. */
2763 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2766 PUT_CODE (reg, MEM);
2767 PUT_MODE (reg, DECL_MODE (decl));
2768 MEM_VOLATILE_P (reg) = TREE_SIDE_EFFECTS (decl);
2769 MEM_IN_STRUCT_P (reg) = AGGREGATE_TYPE_P (type);
2770 MEM_ALIAS_SET (reg) = get_alias_set (decl);
2772 if (TREE_USED (decl) || DECL_INITIAL (decl) != 0)
2773 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type));
2778 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2781 flush_addressof (decl)
2784 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2785 && DECL_RTL (decl) != 0
2786 && GET_CODE (DECL_RTL (decl)) == MEM
2787 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2788 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2789 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0));
2792 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2795 put_addressof_into_stack (r)
2798 tree decl = ADDRESSOF_DECL (r);
2799 rtx reg = XEXP (r, 0);
2801 if (GET_CODE (reg) != REG)
2804 put_reg_into_stack (0, reg, TREE_TYPE (decl), GET_MODE (reg),
2805 DECL_MODE (decl), TREE_SIDE_EFFECTS (decl),
2806 ADDRESSOF_REGNO (r),
2807 TREE_USED (decl) || DECL_INITIAL (decl) != 0);
2810 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2811 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2815 purge_addressof_1 (loc, insn, force, store)
2825 /* Re-start here to avoid recursion in common cases. */
2832 code = GET_CODE (x);
2834 if (code == ADDRESSOF && GET_CODE (XEXP (x, 0)) == MEM)
2837 /* We must create a copy of the rtx because it was created by
2838 overwriting a REG rtx which is always shared. */
2839 rtx sub = copy_rtx (XEXP (XEXP (x, 0), 0));
2841 if (validate_change (insn, loc, sub, 0))
2845 if (! validate_change (insn, loc,
2846 force_operand (sub, NULL_RTX),
2850 insns = gen_sequence ();
2852 emit_insns_before (insns, insn);
2855 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
2857 rtx sub = XEXP (XEXP (x, 0), 0);
2859 if (GET_CODE (sub) == MEM)
2860 sub = gen_rtx_MEM (GET_MODE (x), copy_rtx (XEXP (sub, 0)));
2862 if (GET_CODE (sub) == REG
2863 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
2865 put_addressof_into_stack (XEXP (x, 0));
2868 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
2870 int size_x, size_sub;
2872 size_x = GET_MODE_BITSIZE (GET_MODE (x));
2873 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
2875 /* Don't even consider working with paradoxical subregs,
2876 or the moral equivalent seen here. */
2877 if (size_x < size_sub)
2879 /* Do a bitfield insertion to mirror what would happen
2886 /* If we can't replace with a register, be afraid. */
2889 val = gen_reg_rtx (GET_MODE (x));
2890 if (! validate_change (insn, loc, val, 0))
2892 seq = gen_sequence ();
2894 emit_insn_before (seq, insn);
2897 store_bit_field (sub, size_x, 0, GET_MODE (x),
2898 val, GET_MODE_SIZE (GET_MODE (sub)),
2899 GET_MODE_SIZE (GET_MODE (sub)));
2901 seq = gen_sequence ();
2903 emit_insn_after (seq, insn);
2908 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
2909 GET_MODE (x), GET_MODE (x),
2910 GET_MODE_SIZE (GET_MODE (sub)),
2911 GET_MODE_SIZE (GET_MODE (sub)));
2913 /* If we can't replace with a register, be afraid. */
2914 if (! validate_change (insn, loc, val, 0))
2917 seq = gen_sequence ();
2919 emit_insn_before (seq, insn);
2922 /* We replaced with a reg -- all done. */
2926 else if (validate_change (insn, loc, sub, 0))
2928 /* else give up and put it into the stack */
2930 else if (code == ADDRESSOF)
2932 put_addressof_into_stack (x);
2935 else if (code == SET)
2937 purge_addressof_1 (&SET_DEST (x), insn, force, 1);
2938 purge_addressof_1 (&SET_SRC (x), insn, force, 0);
2942 /* Scan all subexpressions. */
2943 fmt = GET_RTX_FORMAT (code);
2944 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
2947 purge_addressof_1 (&XEXP (x, i), insn, force, 0);
2948 else if (*fmt == 'E')
2949 for (j = 0; j < XVECLEN (x, i); j++)
2950 purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0);
2954 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
2955 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
2959 purge_addressof (insns)
2963 for (insn = insns; insn; insn = NEXT_INSN (insn))
2964 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
2965 || GET_CODE (insn) == CALL_INSN)
2967 purge_addressof_1 (&PATTERN (insn), insn,
2968 asm_noperands (PATTERN (insn)) > 0, 0);
2969 purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0);
2973 /* Pass through the INSNS of function FNDECL and convert virtual register
2974 references to hard register references. */
2977 instantiate_virtual_regs (fndecl, insns)
2984 /* Compute the offsets to use for this function. */
2985 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
2986 var_offset = STARTING_FRAME_OFFSET;
2987 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
2988 out_arg_offset = STACK_POINTER_OFFSET;
2989 cfa_offset = ARG_POINTER_CFA_OFFSET;
2991 /* Scan all variables and parameters of this function. For each that is
2992 in memory, instantiate all virtual registers if the result is a valid
2993 address. If not, we do it later. That will handle most uses of virtual
2994 regs on many machines. */
2995 instantiate_decls (fndecl, 1);
2997 /* Initialize recognition, indicating that volatile is OK. */
3000 /* Scan through all the insns, instantiating every virtual register still
3002 for (insn = insns; insn; insn = NEXT_INSN (insn))
3003 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3004 || GET_CODE (insn) == CALL_INSN)
3006 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3007 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3010 /* Instantiate the stack slots for the parm registers, for later use in
3011 addressof elimination. */
3012 for (i = 0; i < max_parm_reg; ++i)
3013 if (parm_reg_stack_loc[i])
3014 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3016 /* Now instantiate the remaining register equivalences for debugging info.
3017 These will not be valid addresses. */
3018 instantiate_decls (fndecl, 0);
3020 /* Indicate that, from now on, assign_stack_local should use
3021 frame_pointer_rtx. */
3022 virtuals_instantiated = 1;
3025 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3026 all virtual registers in their DECL_RTL's.
3028 If VALID_ONLY, do this only if the resulting address is still valid.
3029 Otherwise, always do it. */
3032 instantiate_decls (fndecl, valid_only)
3038 if (DECL_SAVED_INSNS (fndecl))
3039 /* When compiling an inline function, the obstack used for
3040 rtl allocation is the maybepermanent_obstack. Calling
3041 `resume_temporary_allocation' switches us back to that
3042 obstack while we process this function's parameters. */
3043 resume_temporary_allocation ();
3045 /* Process all parameters of the function. */
3046 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3048 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3050 instantiate_decl (DECL_RTL (decl), size, valid_only);
3052 /* If the parameter was promoted, then the incoming RTL mode may be
3053 larger than the declared type size. We must use the larger of
3055 size = MAX (GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl))), size);
3056 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3059 /* Now process all variables defined in the function or its subblocks. */
3060 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3062 if (DECL_INLINE (fndecl) || DECL_DEFER_OUTPUT (fndecl))
3064 /* Save all rtl allocated for this function by raising the
3065 high-water mark on the maybepermanent_obstack. */
3067 /* All further rtl allocation is now done in the current_obstack. */
3068 rtl_in_current_obstack ();
3072 /* Subroutine of instantiate_decls: Process all decls in the given
3073 BLOCK node and all its subblocks. */
3076 instantiate_decls_1 (let, valid_only)
3082 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3083 instantiate_decl (DECL_RTL (t), int_size_in_bytes (TREE_TYPE (t)),
3086 /* Process all subblocks. */
3087 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3088 instantiate_decls_1 (t, valid_only);
3091 /* Subroutine of the preceding procedures: Given RTL representing a
3092 decl and the size of the object, do any instantiation required.
3094 If VALID_ONLY is non-zero, it means that the RTL should only be
3095 changed if the new address is valid. */
3098 instantiate_decl (x, size, valid_only)
3103 enum machine_mode mode;
3106 /* If this is not a MEM, no need to do anything. Similarly if the
3107 address is a constant or a register that is not a virtual register. */
3109 if (x == 0 || GET_CODE (x) != MEM)
3113 if (CONSTANT_P (addr)
3114 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3115 || (GET_CODE (addr) == REG
3116 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3117 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3120 /* If we should only do this if the address is valid, copy the address.
3121 We need to do this so we can undo any changes that might make the
3122 address invalid. This copy is unfortunate, but probably can't be
3126 addr = copy_rtx (addr);
3128 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3132 /* Now verify that the resulting address is valid for every integer or
3133 floating-point mode up to and including SIZE bytes long. We do this
3134 since the object might be accessed in any mode and frame addresses
3137 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3138 mode != VOIDmode && GET_MODE_SIZE (mode) <= size;
3139 mode = GET_MODE_WIDER_MODE (mode))
3140 if (! memory_address_p (mode, addr))
3143 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3144 mode != VOIDmode && GET_MODE_SIZE (mode) <= size;
3145 mode = GET_MODE_WIDER_MODE (mode))
3146 if (! memory_address_p (mode, addr))
3150 /* Put back the address now that we have updated it and we either know
3151 it is valid or we don't care whether it is valid. */
3156 /* Given a pointer to a piece of rtx and an optional pointer to the
3157 containing object, instantiate any virtual registers present in it.
3159 If EXTRA_INSNS, we always do the replacement and generate
3160 any extra insns before OBJECT. If it zero, we do nothing if replacement
3163 Return 1 if we either had nothing to do or if we were able to do the
3164 needed replacement. Return 0 otherwise; we only return zero if
3165 EXTRA_INSNS is zero.
3167 We first try some simple transformations to avoid the creation of extra
3171 instantiate_virtual_regs_1 (loc, object, extra_insns)
3179 HOST_WIDE_INT offset;
3185 /* Re-start here to avoid recursion in common cases. */
3192 code = GET_CODE (x);
3194 /* Check for some special cases. */
3211 /* We are allowed to set the virtual registers. This means that
3212 the actual register should receive the source minus the
3213 appropriate offset. This is used, for example, in the handling
3214 of non-local gotos. */
3215 if (SET_DEST (x) == virtual_incoming_args_rtx)
3216 new = arg_pointer_rtx, offset = - in_arg_offset;
3217 else if (SET_DEST (x) == virtual_stack_vars_rtx)
3218 new = frame_pointer_rtx, offset = - var_offset;
3219 else if (SET_DEST (x) == virtual_stack_dynamic_rtx)
3220 new = stack_pointer_rtx, offset = - dynamic_offset;
3221 else if (SET_DEST (x) == virtual_outgoing_args_rtx)
3222 new = stack_pointer_rtx, offset = - out_arg_offset;
3223 else if (SET_DEST (x) == virtual_cfa_rtx)
3224 new = arg_pointer_rtx, offset = - cfa_offset;
3228 /* The only valid sources here are PLUS or REG. Just do
3229 the simplest possible thing to handle them. */
3230 if (GET_CODE (SET_SRC (x)) != REG
3231 && GET_CODE (SET_SRC (x)) != PLUS)
3235 if (GET_CODE (SET_SRC (x)) != REG)
3236 temp = force_operand (SET_SRC (x), NULL_RTX);
3239 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3243 emit_insns_before (seq, object);
3246 if (! validate_change (object, &SET_SRC (x), temp, 0)
3253 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3258 /* Handle special case of virtual register plus constant. */
3259 if (CONSTANT_P (XEXP (x, 1)))
3261 rtx old, new_offset;
3263 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3264 if (GET_CODE (XEXP (x, 0)) == PLUS)
3266 rtx inner = XEXP (XEXP (x, 0), 0);
3268 if (inner == virtual_incoming_args_rtx)
3269 new = arg_pointer_rtx, offset = in_arg_offset;
3270 else if (inner == virtual_stack_vars_rtx)
3271 new = frame_pointer_rtx, offset = var_offset;
3272 else if (inner == virtual_stack_dynamic_rtx)
3273 new = stack_pointer_rtx, offset = dynamic_offset;
3274 else if (inner == virtual_outgoing_args_rtx)
3275 new = stack_pointer_rtx, offset = out_arg_offset;
3276 else if (inner == virtual_cfa_rtx)
3277 new = arg_pointer_rtx, offset = cfa_offset;
3284 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3286 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3289 else if (XEXP (x, 0) == virtual_incoming_args_rtx)
3290 new = arg_pointer_rtx, offset = in_arg_offset;
3291 else if (XEXP (x, 0) == virtual_stack_vars_rtx)
3292 new = frame_pointer_rtx, offset = var_offset;
3293 else if (XEXP (x, 0) == virtual_stack_dynamic_rtx)
3294 new = stack_pointer_rtx, offset = dynamic_offset;
3295 else if (XEXP (x, 0) == virtual_outgoing_args_rtx)
3296 new = stack_pointer_rtx, offset = out_arg_offset;
3297 else if (XEXP (x, 0) == virtual_cfa_rtx)
3298 new = arg_pointer_rtx, offset = cfa_offset;
3301 /* We know the second operand is a constant. Unless the
3302 first operand is a REG (which has been already checked),
3303 it needs to be checked. */
3304 if (GET_CODE (XEXP (x, 0)) != REG)
3312 new_offset = plus_constant (XEXP (x, 1), offset);
3314 /* If the new constant is zero, try to replace the sum with just
3316 if (new_offset == const0_rtx
3317 && validate_change (object, loc, new, 0))
3320 /* Next try to replace the register and new offset.
3321 There are two changes to validate here and we can't assume that
3322 in the case of old offset equals new just changing the register
3323 will yield a valid insn. In the interests of a little efficiency,
3324 however, we only call validate change once (we don't queue up the
3325 changes and then call apply_change_group). */
3329 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3330 : (XEXP (x, 0) = new,
3331 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3339 /* Otherwise copy the new constant into a register and replace
3340 constant with that register. */
3341 temp = gen_reg_rtx (Pmode);
3343 if (validate_change (object, &XEXP (x, 1), temp, 0))
3344 emit_insn_before (gen_move_insn (temp, new_offset), object);
3347 /* If that didn't work, replace this expression with a
3348 register containing the sum. */
3351 new = gen_rtx_PLUS (Pmode, new, new_offset);
3354 temp = force_operand (new, NULL_RTX);
3358 emit_insns_before (seq, object);
3359 if (! validate_change (object, loc, temp, 0)
3360 && ! validate_replace_rtx (x, temp, object))
3368 /* Fall through to generic two-operand expression case. */
3374 case DIV: case UDIV:
3375 case MOD: case UMOD:
3376 case AND: case IOR: case XOR:
3377 case ROTATERT: case ROTATE:
3378 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3380 case GE: case GT: case GEU: case GTU:
3381 case LE: case LT: case LEU: case LTU:
3382 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3383 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3388 /* Most cases of MEM that convert to valid addresses have already been
3389 handled by our scan of decls. The only special handling we
3390 need here is to make a copy of the rtx to ensure it isn't being
3391 shared if we have to change it to a pseudo.
3393 If the rtx is a simple reference to an address via a virtual register,
3394 it can potentially be shared. In such cases, first try to make it
3395 a valid address, which can also be shared. Otherwise, copy it and
3398 First check for common cases that need no processing. These are
3399 usually due to instantiation already being done on a previous instance
3403 if (CONSTANT_ADDRESS_P (temp)
3404 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3405 || temp == arg_pointer_rtx
3407 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3408 || temp == hard_frame_pointer_rtx
3410 || temp == frame_pointer_rtx)
3413 if (GET_CODE (temp) == PLUS
3414 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3415 && (XEXP (temp, 0) == frame_pointer_rtx
3416 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3417 || XEXP (temp, 0) == hard_frame_pointer_rtx
3419 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3420 || XEXP (temp, 0) == arg_pointer_rtx
3425 if (temp == virtual_stack_vars_rtx
3426 || temp == virtual_incoming_args_rtx
3427 || (GET_CODE (temp) == PLUS
3428 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3429 && (XEXP (temp, 0) == virtual_stack_vars_rtx
3430 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
3432 /* This MEM may be shared. If the substitution can be done without
3433 the need to generate new pseudos, we want to do it in place
3434 so all copies of the shared rtx benefit. The call below will
3435 only make substitutions if the resulting address is still
3438 Note that we cannot pass X as the object in the recursive call
3439 since the insn being processed may not allow all valid
3440 addresses. However, if we were not passed on object, we can
3441 only modify X without copying it if X will have a valid
3444 ??? Also note that this can still lose if OBJECT is an insn that
3445 has less restrictions on an address that some other insn.
3446 In that case, we will modify the shared address. This case
3447 doesn't seem very likely, though. One case where this could
3448 happen is in the case of a USE or CLOBBER reference, but we
3449 take care of that below. */
3451 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
3452 object ? object : x, 0))
3455 /* Otherwise make a copy and process that copy. We copy the entire
3456 RTL expression since it might be a PLUS which could also be
3458 *loc = x = copy_rtx (x);
3461 /* Fall through to generic unary operation case. */
3463 case STRICT_LOW_PART:
3465 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
3466 case SIGN_EXTEND: case ZERO_EXTEND:
3467 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
3468 case FLOAT: case FIX:
3469 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
3473 /* These case either have just one operand or we know that we need not
3474 check the rest of the operands. */
3480 /* If the operand is a MEM, see if the change is a valid MEM. If not,
3481 go ahead and make the invalid one, but do it to a copy. For a REG,
3482 just make the recursive call, since there's no chance of a problem. */
3484 if ((GET_CODE (XEXP (x, 0)) == MEM
3485 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
3487 || (GET_CODE (XEXP (x, 0)) == REG
3488 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
3491 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
3496 /* Try to replace with a PLUS. If that doesn't work, compute the sum
3497 in front of this insn and substitute the temporary. */
3498 if (x == virtual_incoming_args_rtx)
3499 new = arg_pointer_rtx, offset = in_arg_offset;
3500 else if (x == virtual_stack_vars_rtx)
3501 new = frame_pointer_rtx, offset = var_offset;
3502 else if (x == virtual_stack_dynamic_rtx)
3503 new = stack_pointer_rtx, offset = dynamic_offset;
3504 else if (x == virtual_outgoing_args_rtx)
3505 new = stack_pointer_rtx, offset = out_arg_offset;
3506 else if (x == virtual_cfa_rtx)
3507 new = arg_pointer_rtx, offset = cfa_offset;
3511 temp = plus_constant (new, offset);
3512 if (!validate_change (object, loc, temp, 0))
3518 temp = force_operand (temp, NULL_RTX);
3522 emit_insns_before (seq, object);
3523 if (! validate_change (object, loc, temp, 0)
3524 && ! validate_replace_rtx (x, temp, object))
3532 if (GET_CODE (XEXP (x, 0)) == REG)
3535 else if (GET_CODE (XEXP (x, 0)) == MEM)
3537 /* If we have a (addressof (mem ..)), do any instantiation inside
3538 since we know we'll be making the inside valid when we finally
3539 remove the ADDRESSOF. */
3540 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
3549 /* Scan all subexpressions. */
3550 fmt = GET_RTX_FORMAT (code);
3551 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3554 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
3557 else if (*fmt == 'E')
3558 for (j = 0; j < XVECLEN (x, i); j++)
3559 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
3566 /* Optimization: assuming this function does not receive nonlocal gotos,
3567 delete the handlers for such, as well as the insns to establish
3568 and disestablish them. */
3574 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3576 /* Delete the handler by turning off the flag that would
3577 prevent jump_optimize from deleting it.
3578 Also permit deletion of the nonlocal labels themselves
3579 if nothing local refers to them. */
3580 if (GET_CODE (insn) == CODE_LABEL)
3584 LABEL_PRESERVE_P (insn) = 0;
3586 /* Remove it from the nonlocal_label list, to avoid confusing
3588 for (t = nonlocal_labels, last_t = 0; t;
3589 last_t = t, t = TREE_CHAIN (t))
3590 if (DECL_RTL (TREE_VALUE (t)) == insn)
3595 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
3597 TREE_CHAIN (last_t) = TREE_CHAIN (t);
3600 if (GET_CODE (insn) == INSN
3601 && ((nonlocal_goto_handler_slot != 0
3602 && reg_mentioned_p (nonlocal_goto_handler_slot, PATTERN (insn)))
3603 || (nonlocal_goto_stack_level != 0
3604 && reg_mentioned_p (nonlocal_goto_stack_level,
3610 /* Return a list (chain of EXPR_LIST nodes) for the nonlocal labels
3611 of the current function. */
3614 nonlocal_label_rtx_list ()
3619 for (t = nonlocal_labels; t; t = TREE_CHAIN (t))
3620 x = gen_rtx_EXPR_LIST (VOIDmode, label_rtx (TREE_VALUE (t)), x);
3625 /* Output a USE for any register use in RTL.
3626 This is used with -noreg to mark the extent of lifespan
3627 of any registers used in a user-visible variable's DECL_RTL. */
3633 if (GET_CODE (rtl) == REG)
3634 /* This is a register variable. */
3635 emit_insn (gen_rtx_USE (VOIDmode, rtl));
3636 else if (GET_CODE (rtl) == MEM
3637 && GET_CODE (XEXP (rtl, 0)) == REG
3638 && (REGNO (XEXP (rtl, 0)) < FIRST_VIRTUAL_REGISTER
3639 || REGNO (XEXP (rtl, 0)) > LAST_VIRTUAL_REGISTER)
3640 && XEXP (rtl, 0) != current_function_internal_arg_pointer)
3641 /* This is a variable-sized structure. */
3642 emit_insn (gen_rtx_USE (VOIDmode, XEXP (rtl, 0)));
3645 /* Like use_variable except that it outputs the USEs after INSN
3646 instead of at the end of the insn-chain. */
3649 use_variable_after (rtl, insn)
3652 if (GET_CODE (rtl) == REG)
3653 /* This is a register variable. */
3654 emit_insn_after (gen_rtx_USE (VOIDmode, rtl), insn);
3655 else if (GET_CODE (rtl) == MEM
3656 && GET_CODE (XEXP (rtl, 0)) == REG
3657 && (REGNO (XEXP (rtl, 0)) < FIRST_VIRTUAL_REGISTER
3658 || REGNO (XEXP (rtl, 0)) > LAST_VIRTUAL_REGISTER)
3659 && XEXP (rtl, 0) != current_function_internal_arg_pointer)
3660 /* This is a variable-sized structure. */
3661 emit_insn_after (gen_rtx_USE (VOIDmode, XEXP (rtl, 0)), insn);
3667 return max_parm_reg;
3670 /* Return the first insn following those generated by `assign_parms'. */
3673 get_first_nonparm_insn ()
3676 return NEXT_INSN (last_parm_insn);
3677 return get_insns ();
3680 /* Return the first NOTE_INSN_BLOCK_BEG note in the function.
3681 Crash if there is none. */
3684 get_first_block_beg ()
3686 register rtx searcher;
3687 register rtx insn = get_first_nonparm_insn ();
3689 for (searcher = insn; searcher; searcher = NEXT_INSN (searcher))
3690 if (GET_CODE (searcher) == NOTE
3691 && NOTE_LINE_NUMBER (searcher) == NOTE_INSN_BLOCK_BEG)
3694 abort (); /* Invalid call to this function. (See comments above.) */
3698 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
3699 This means a type for which function calls must pass an address to the
3700 function or get an address back from the function.
3701 EXP may be a type node or an expression (whose type is tested). */
3704 aggregate_value_p (exp)
3707 int i, regno, nregs;
3710 if (TREE_CODE_CLASS (TREE_CODE (exp)) == 't')
3713 type = TREE_TYPE (exp);
3715 if (RETURN_IN_MEMORY (type))
3717 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
3718 and thus can't be returned in registers. */
3719 if (TREE_ADDRESSABLE (type))
3721 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
3723 /* Make sure we have suitable call-clobbered regs to return
3724 the value in; if not, we must return it in memory. */
3725 reg = hard_function_value (type, 0);
3727 /* If we have something other than a REG (e.g. a PARALLEL), then assume
3729 if (GET_CODE (reg) != REG)
3732 regno = REGNO (reg);
3733 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
3734 for (i = 0; i < nregs; i++)
3735 if (! call_used_regs[regno + i])
3740 /* Assign RTL expressions to the function's parameters.
3741 This may involve copying them into registers and using
3742 those registers as the RTL for them.
3744 If SECOND_TIME is non-zero it means that this function is being
3745 called a second time. This is done by integrate.c when a function's
3746 compilation is deferred. We need to come back here in case the
3747 FUNCTION_ARG macro computes items needed for the rest of the compilation
3748 (such as changing which registers are fixed or caller-saved). But suppress
3749 writing any insns or setting DECL_RTL of anything in this case. */
3752 assign_parms (fndecl, second_time)
3757 register rtx entry_parm = 0;
3758 register rtx stack_parm = 0;
3759 CUMULATIVE_ARGS args_so_far;
3760 enum machine_mode promoted_mode, passed_mode;
3761 enum machine_mode nominal_mode, promoted_nominal_mode;
3763 /* Total space needed so far for args on the stack,
3764 given as a constant and a tree-expression. */
3765 struct args_size stack_args_size;
3766 tree fntype = TREE_TYPE (fndecl);
3767 tree fnargs = DECL_ARGUMENTS (fndecl);
3768 /* This is used for the arg pointer when referring to stack args. */
3769 rtx internal_arg_pointer;
3770 /* This is a dummy PARM_DECL that we used for the function result if
3771 the function returns a structure. */
3772 tree function_result_decl = 0;
3773 int varargs_setup = 0;
3774 rtx conversion_insns = 0;
3776 /* Nonzero if the last arg is named `__builtin_va_alist',
3777 which is used on some machines for old-fashioned non-ANSI varargs.h;
3778 this should be stuck onto the stack as if it had arrived there. */
3780 = (current_function_varargs
3782 && (parm = tree_last (fnargs)) != 0
3784 && (! strcmp (IDENTIFIER_POINTER (DECL_NAME (parm)),
3785 "__builtin_va_alist")));
3787 /* Nonzero if function takes extra anonymous args.
3788 This means the last named arg must be on the stack
3789 right before the anonymous ones. */
3791 = (TYPE_ARG_TYPES (fntype) != 0
3792 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
3793 != void_type_node));
3795 current_function_stdarg = stdarg;
3797 /* If the reg that the virtual arg pointer will be translated into is
3798 not a fixed reg or is the stack pointer, make a copy of the virtual
3799 arg pointer, and address parms via the copy. The frame pointer is
3800 considered fixed even though it is not marked as such.
3802 The second time through, simply use ap to avoid generating rtx. */
3804 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
3805 || ! (fixed_regs[ARG_POINTER_REGNUM]
3806 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM))
3808 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
3810 internal_arg_pointer = virtual_incoming_args_rtx;
3811 current_function_internal_arg_pointer = internal_arg_pointer;
3813 stack_args_size.constant = 0;
3814 stack_args_size.var = 0;
3816 /* If struct value address is treated as the first argument, make it so. */
3817 if (aggregate_value_p (DECL_RESULT (fndecl))
3818 && ! current_function_returns_pcc_struct
3819 && struct_value_incoming_rtx == 0)
3821 tree type = build_pointer_type (TREE_TYPE (fntype));
3823 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
3825 DECL_ARG_TYPE (function_result_decl) = type;
3826 TREE_CHAIN (function_result_decl) = fnargs;
3827 fnargs = function_result_decl;
3830 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
3831 parm_reg_stack_loc = (rtx *) savealloc (max_parm_reg * sizeof (rtx));
3832 bzero ((char *) parm_reg_stack_loc, max_parm_reg * sizeof (rtx));
3834 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
3835 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
3837 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, 0);
3840 /* We haven't yet found an argument that we must push and pretend the
3842 current_function_pretend_args_size = 0;
3844 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
3846 int aggregate = AGGREGATE_TYPE_P (TREE_TYPE (parm));
3847 struct args_size stack_offset;
3848 struct args_size arg_size;
3849 int passed_pointer = 0;
3850 int did_conversion = 0;
3851 tree passed_type = DECL_ARG_TYPE (parm);
3852 tree nominal_type = TREE_TYPE (parm);
3854 /* Set LAST_NAMED if this is last named arg before some
3856 int last_named = ((TREE_CHAIN (parm) == 0
3857 || DECL_NAME (TREE_CHAIN (parm)) == 0)
3858 && (stdarg || current_function_varargs));
3859 /* Set NAMED_ARG if this arg should be treated as a named arg. For
3860 most machines, if this is a varargs/stdarg function, then we treat
3861 the last named arg as if it were anonymous too. */
3862 int named_arg = STRICT_ARGUMENT_NAMING ? 1 : ! last_named;
3864 if (TREE_TYPE (parm) == error_mark_node
3865 /* This can happen after weird syntax errors
3866 or if an enum type is defined among the parms. */
3867 || TREE_CODE (parm) != PARM_DECL
3868 || passed_type == NULL)
3870 DECL_INCOMING_RTL (parm) = DECL_RTL (parm)
3871 = gen_rtx_MEM (BLKmode, const0_rtx);
3872 TREE_USED (parm) = 1;
3876 /* For varargs.h function, save info about regs and stack space
3877 used by the individual args, not including the va_alist arg. */
3878 if (hide_last_arg && last_named)
3879 current_function_args_info = args_so_far;
3881 /* Find mode of arg as it is passed, and mode of arg
3882 as it should be during execution of this function. */
3883 passed_mode = TYPE_MODE (passed_type);
3884 nominal_mode = TYPE_MODE (nominal_type);
3886 /* If the parm's mode is VOID, its value doesn't matter,
3887 and avoid the usual things like emit_move_insn that could crash. */
3888 if (nominal_mode == VOIDmode)
3890 DECL_INCOMING_RTL (parm) = DECL_RTL (parm) = const0_rtx;
3894 /* If the parm is to be passed as a transparent union, use the
3895 type of the first field for the tests below. We have already
3896 verified that the modes are the same. */
3897 if (DECL_TRANSPARENT_UNION (parm)
3898 || TYPE_TRANSPARENT_UNION (passed_type))
3899 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
3901 /* See if this arg was passed by invisible reference. It is if
3902 it is an object whose size depends on the contents of the
3903 object itself or if the machine requires these objects be passed
3906 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
3907 && contains_placeholder_p (TYPE_SIZE (passed_type)))
3908 || TREE_ADDRESSABLE (passed_type)
3909 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3910 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
3911 passed_type, named_arg)
3915 passed_type = nominal_type = build_pointer_type (passed_type);
3917 passed_mode = nominal_mode = Pmode;
3920 promoted_mode = passed_mode;
3922 #ifdef PROMOTE_FUNCTION_ARGS
3923 /* Compute the mode in which the arg is actually extended to. */
3924 unsignedp = TREE_UNSIGNED (passed_type);
3925 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
3928 /* Let machine desc say which reg (if any) the parm arrives in.
3929 0 means it arrives on the stack. */
3930 #ifdef FUNCTION_INCOMING_ARG
3931 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
3932 passed_type, named_arg);
3934 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
3935 passed_type, named_arg);
3938 if (entry_parm == 0)
3939 promoted_mode = passed_mode;
3941 #ifdef SETUP_INCOMING_VARARGS
3942 /* If this is the last named parameter, do any required setup for
3943 varargs or stdargs. We need to know about the case of this being an
3944 addressable type, in which case we skip the registers it
3945 would have arrived in.
3947 For stdargs, LAST_NAMED will be set for two parameters, the one that
3948 is actually the last named, and the dummy parameter. We only
3949 want to do this action once.
3951 Also, indicate when RTL generation is to be suppressed. */
3952 if (last_named && !varargs_setup)
3954 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
3955 current_function_pretend_args_size,
3961 /* Determine parm's home in the stack,
3962 in case it arrives in the stack or we should pretend it did.
3964 Compute the stack position and rtx where the argument arrives
3967 There is one complexity here: If this was a parameter that would
3968 have been passed in registers, but wasn't only because it is
3969 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
3970 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
3971 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
3972 0 as it was the previous time. */
3974 locate_and_pad_parm (promoted_mode, passed_type,
3975 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3978 #ifdef FUNCTION_INCOMING_ARG
3979 FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
3982 || varargs_setup)) != 0,
3984 FUNCTION_ARG (args_so_far, promoted_mode,
3986 named_arg || varargs_setup) != 0,
3989 fndecl, &stack_args_size, &stack_offset, &arg_size);
3993 rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
3995 if (offset_rtx == const0_rtx)
3996 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
3998 stack_parm = gen_rtx_MEM (promoted_mode,
3999 gen_rtx_PLUS (Pmode,
4000 internal_arg_pointer,
4003 /* If this is a memory ref that contains aggregate components,
4004 mark it as such for cse and loop optimize. Likewise if it
4006 MEM_IN_STRUCT_P (stack_parm) = aggregate;
4007 RTX_UNCHANGING_P (stack_parm) = TREE_READONLY (parm);
4008 MEM_ALIAS_SET (stack_parm) = get_alias_set (parm);
4011 /* If this parameter was passed both in registers and in the stack,
4012 use the copy on the stack. */
4013 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4016 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4017 /* If this parm was passed part in regs and part in memory,
4018 pretend it arrived entirely in memory
4019 by pushing the register-part onto the stack.
4021 In the special case of a DImode or DFmode that is split,
4022 we could put it together in a pseudoreg directly,
4023 but for now that's not worth bothering with. */
4027 int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4028 passed_type, named_arg);
4032 current_function_pretend_args_size
4033 = (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
4034 / (PARM_BOUNDARY / BITS_PER_UNIT)
4035 * (PARM_BOUNDARY / BITS_PER_UNIT));
4039 /* Handle calls that pass values in multiple non-contiguous
4040 locations. The Irix 6 ABI has examples of this. */
4041 if (GET_CODE (entry_parm) == PARALLEL)
4042 emit_group_store (validize_mem (stack_parm), entry_parm,
4043 int_size_in_bytes (TREE_TYPE (parm)),
4044 (TYPE_ALIGN (TREE_TYPE (parm))
4047 move_block_from_reg (REGNO (entry_parm),
4048 validize_mem (stack_parm), nregs,
4049 int_size_in_bytes (TREE_TYPE (parm)));
4051 entry_parm = stack_parm;
4056 /* If we didn't decide this parm came in a register,
4057 by default it came on the stack. */
4058 if (entry_parm == 0)
4059 entry_parm = stack_parm;
4061 /* Record permanently how this parm was passed. */
4063 DECL_INCOMING_RTL (parm) = entry_parm;
4065 /* If there is actually space on the stack for this parm,
4066 count it in stack_args_size; otherwise set stack_parm to 0
4067 to indicate there is no preallocated stack slot for the parm. */
4069 if (entry_parm == stack_parm
4070 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4071 /* On some machines, even if a parm value arrives in a register
4072 there is still an (uninitialized) stack slot allocated for it.
4074 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4075 whether this parameter already has a stack slot allocated,
4076 because an arg block exists only if current_function_args_size
4077 is larger than some threshold, and we haven't calculated that
4078 yet. So, for now, we just assume that stack slots never exist
4080 || REG_PARM_STACK_SPACE (fndecl) > 0
4084 stack_args_size.constant += arg_size.constant;
4086 ADD_PARM_SIZE (stack_args_size, arg_size.var);
4089 /* No stack slot was pushed for this parm. */
4092 /* Update info on where next arg arrives in registers. */
4094 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4095 passed_type, named_arg);
4097 /* If this is our second time through, we are done with this parm. */
4101 /* If we can't trust the parm stack slot to be aligned enough
4102 for its ultimate type, don't use that slot after entry.
4103 We'll make another stack slot, if we need one. */
4105 int thisparm_boundary
4106 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4108 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4112 /* If parm was passed in memory, and we need to convert it on entry,
4113 don't store it back in that same slot. */
4115 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4119 /* Now adjust STACK_PARM to the mode and precise location
4120 where this parameter should live during execution,
4121 if we discover that it must live in the stack during execution.
4122 To make debuggers happier on big-endian machines, we store
4123 the value in the last bytes of the space available. */
4125 if (nominal_mode != BLKmode && nominal_mode != passed_mode
4130 if (BYTES_BIG_ENDIAN
4131 && GET_MODE_SIZE (nominal_mode) < UNITS_PER_WORD)
4132 stack_offset.constant += (GET_MODE_SIZE (passed_mode)
4133 - GET_MODE_SIZE (nominal_mode));
4135 offset_rtx = ARGS_SIZE_RTX (stack_offset);
4136 if (offset_rtx == const0_rtx)
4137 stack_parm = gen_rtx_MEM (nominal_mode, internal_arg_pointer);
4139 stack_parm = gen_rtx_MEM (nominal_mode,
4140 gen_rtx_PLUS (Pmode,
4141 internal_arg_pointer,
4144 /* If this is a memory ref that contains aggregate components,
4145 mark it as such for cse and loop optimize. */
4146 MEM_IN_STRUCT_P (stack_parm) = aggregate;
4151 /* We need this "use" info, because the gcc-register->stack-register
4152 converter in reg-stack.c needs to know which registers are active
4153 at the start of the function call. The actual parameter loading
4154 instructions are not always available then anymore, since they might
4155 have been optimised away. */
4157 if (GET_CODE (entry_parm) == REG && !(hide_last_arg && last_named))
4158 emit_insn (gen_rtx_USE (GET_MODE (entry_parm), entry_parm));
4161 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4162 in the mode in which it arrives.
4163 STACK_PARM is an RTX for a stack slot where the parameter can live
4164 during the function (in case we want to put it there).
4165 STACK_PARM is 0 if no stack slot was pushed for it.
4167 Now output code if necessary to convert ENTRY_PARM to
4168 the type in which this function declares it,
4169 and store that result in an appropriate place,
4170 which may be a pseudo reg, may be STACK_PARM,
4171 or may be a local stack slot if STACK_PARM is 0.
4173 Set DECL_RTL to that place. */
4175 if (nominal_mode == BLKmode || GET_CODE (entry_parm) == PARALLEL)
4177 /* If a BLKmode arrives in registers, copy it to a stack slot.
4178 Handle calls that pass values in multiple non-contiguous
4179 locations. The Irix 6 ABI has examples of this. */
4180 if (GET_CODE (entry_parm) == REG
4181 || GET_CODE (entry_parm) == PARALLEL)
4184 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
4187 /* Note that we will be storing an integral number of words.
4188 So we have to be careful to ensure that we allocate an
4189 integral number of words. We do this below in the
4190 assign_stack_local if space was not allocated in the argument
4191 list. If it was, this will not work if PARM_BOUNDARY is not
4192 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4193 if it becomes a problem. */
4195 if (stack_parm == 0)
4198 = assign_stack_local (GET_MODE (entry_parm),
4201 /* If this is a memory ref that contains aggregate
4202 components, mark it as such for cse and loop optimize. */
4203 MEM_IN_STRUCT_P (stack_parm) = aggregate;
4206 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4209 if (TREE_READONLY (parm))
4210 RTX_UNCHANGING_P (stack_parm) = 1;
4212 /* Handle calls that pass values in multiple non-contiguous
4213 locations. The Irix 6 ABI has examples of this. */
4214 if (GET_CODE (entry_parm) == PARALLEL)
4215 emit_group_store (validize_mem (stack_parm), entry_parm,
4216 int_size_in_bytes (TREE_TYPE (parm)),
4217 (TYPE_ALIGN (TREE_TYPE (parm))
4220 move_block_from_reg (REGNO (entry_parm),
4221 validize_mem (stack_parm),
4222 size_stored / UNITS_PER_WORD,
4223 int_size_in_bytes (TREE_TYPE (parm)));
4225 DECL_RTL (parm) = stack_parm;
4227 else if (! ((obey_regdecls && ! DECL_REGISTER (parm)
4228 && ! DECL_INLINE (fndecl))
4229 /* layout_decl may set this. */
4230 || TREE_ADDRESSABLE (parm)
4231 || TREE_SIDE_EFFECTS (parm)
4232 /* If -ffloat-store specified, don't put explicit
4233 float variables into registers. */
4234 || (flag_float_store
4235 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4236 /* Always assign pseudo to structure return or item passed
4237 by invisible reference. */
4238 || passed_pointer || parm == function_result_decl)
4240 /* Store the parm in a pseudoregister during the function, but we
4241 may need to do it in a wider mode. */
4243 register rtx parmreg;
4244 int regno, regnoi = 0, regnor = 0;
4246 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4248 promoted_nominal_mode
4249 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4251 parmreg = gen_reg_rtx (promoted_nominal_mode);
4252 mark_user_reg (parmreg);
4254 /* If this was an item that we received a pointer to, set DECL_RTL
4259 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)), parmreg);
4260 MEM_IN_STRUCT_P (DECL_RTL (parm)) = aggregate;
4263 DECL_RTL (parm) = parmreg;
4265 /* Copy the value into the register. */
4266 if (nominal_mode != passed_mode
4267 || promoted_nominal_mode != promoted_mode)
4269 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4270 mode, by the caller. We now have to convert it to
4271 NOMINAL_MODE, if different. However, PARMREG may be in
4272 a different mode than NOMINAL_MODE if it is being stored
4275 If ENTRY_PARM is a hard register, it might be in a register
4276 not valid for operating in its mode (e.g., an odd-numbered
4277 register for a DFmode). In that case, moves are the only
4278 thing valid, so we can't do a convert from there. This
4279 occurs when the calling sequence allow such misaligned
4282 In addition, the conversion may involve a call, which could
4283 clobber parameters which haven't been copied to pseudo
4284 registers yet. Therefore, we must first copy the parm to
4285 a pseudo reg here, and save the conversion until after all
4286 parameters have been moved. */
4288 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4290 emit_move_insn (tempreg, validize_mem (entry_parm));
4292 push_to_sequence (conversion_insns);
4293 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4295 expand_assignment (parm,
4296 make_tree (nominal_type, tempreg), 0, 0);
4297 conversion_insns = get_insns ();
4302 emit_move_insn (parmreg, validize_mem (entry_parm));
4304 /* If we were passed a pointer but the actual value
4305 can safely live in a register, put it in one. */
4306 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4307 && ! ((obey_regdecls && ! DECL_REGISTER (parm)
4308 && ! DECL_INLINE (fndecl))
4309 /* layout_decl may set this. */
4310 || TREE_ADDRESSABLE (parm)
4311 || TREE_SIDE_EFFECTS (parm)
4312 /* If -ffloat-store specified, don't put explicit
4313 float variables into registers. */
4314 || (flag_float_store
4315 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE)))
4317 /* We can't use nominal_mode, because it will have been set to
4318 Pmode above. We must use the actual mode of the parm. */
4319 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4320 mark_user_reg (parmreg);
4321 emit_move_insn (parmreg, DECL_RTL (parm));
4322 DECL_RTL (parm) = parmreg;
4323 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4327 #ifdef FUNCTION_ARG_CALLEE_COPIES
4328 /* If we are passed an arg by reference and it is our responsibility
4329 to make a copy, do it now.
4330 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4331 original argument, so we must recreate them in the call to
4332 FUNCTION_ARG_CALLEE_COPIES. */
4333 /* ??? Later add code to handle the case that if the argument isn't
4334 modified, don't do the copy. */
4336 else if (passed_pointer
4337 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4338 TYPE_MODE (DECL_ARG_TYPE (parm)),
4339 DECL_ARG_TYPE (parm),
4341 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4344 tree type = DECL_ARG_TYPE (parm);
4346 /* This sequence may involve a library call perhaps clobbering
4347 registers that haven't been copied to pseudos yet. */
4349 push_to_sequence (conversion_insns);
4351 if (TYPE_SIZE (type) == 0
4352 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4353 /* This is a variable sized object. */
4354 copy = gen_rtx_MEM (BLKmode,
4355 allocate_dynamic_stack_space
4356 (expr_size (parm), NULL_RTX,
4357 TYPE_ALIGN (type)));
4359 copy = assign_stack_temp (TYPE_MODE (type),
4360 int_size_in_bytes (type), 1);
4361 MEM_IN_STRUCT_P (copy) = AGGREGATE_TYPE_P (type);
4362 RTX_UNCHANGING_P (copy) = TREE_READONLY (parm);
4364 store_expr (parm, copy, 0);
4365 emit_move_insn (parmreg, XEXP (copy, 0));
4366 if (flag_check_memory_usage)
4367 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
4368 XEXP (copy, 0), ptr_mode,
4369 GEN_INT (int_size_in_bytes (type)),
4370 TYPE_MODE (sizetype),
4371 GEN_INT (MEMORY_USE_RW),
4372 TYPE_MODE (integer_type_node));
4373 conversion_insns = get_insns ();
4377 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4379 /* In any case, record the parm's desired stack location
4380 in case we later discover it must live in the stack.
4382 If it is a COMPLEX value, store the stack location for both
4385 if (GET_CODE (parmreg) == CONCAT)
4386 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4388 regno = REGNO (parmreg);
4390 if (regno >= max_parm_reg)
4393 int old_max_parm_reg = max_parm_reg;
4395 /* It's slow to expand this one register at a time,
4396 but it's also rare and we need max_parm_reg to be
4397 precisely correct. */
4398 max_parm_reg = regno + 1;
4399 new = (rtx *) savealloc (max_parm_reg * sizeof (rtx));
4400 bcopy ((char *) parm_reg_stack_loc, (char *) new,
4401 old_max_parm_reg * sizeof (rtx));
4402 bzero ((char *) (new + old_max_parm_reg),
4403 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4404 parm_reg_stack_loc = new;
4407 if (GET_CODE (parmreg) == CONCAT)
4409 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
4411 regnor = REGNO (gen_realpart (submode, parmreg));
4412 regnoi = REGNO (gen_imagpart (submode, parmreg));
4414 if (stack_parm != 0)
4416 parm_reg_stack_loc[regnor]
4417 = gen_realpart (submode, stack_parm);
4418 parm_reg_stack_loc[regnoi]
4419 = gen_imagpart (submode, stack_parm);
4423 parm_reg_stack_loc[regnor] = 0;
4424 parm_reg_stack_loc[regnoi] = 0;
4428 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
4430 /* Mark the register as eliminable if we did no conversion
4431 and it was copied from memory at a fixed offset,
4432 and the arg pointer was not copied to a pseudo-reg.
4433 If the arg pointer is a pseudo reg or the offset formed
4434 an invalid address, such memory-equivalences
4435 as we make here would screw up life analysis for it. */
4436 if (nominal_mode == passed_mode
4439 && GET_CODE (stack_parm) == MEM
4440 && stack_offset.var == 0
4441 && reg_mentioned_p (virtual_incoming_args_rtx,
4442 XEXP (stack_parm, 0)))
4444 rtx linsn = get_last_insn ();
4447 /* Mark complex types separately. */
4448 if (GET_CODE (parmreg) == CONCAT)
4449 /* Scan backwards for the set of the real and
4451 for (sinsn = linsn; sinsn != 0;
4452 sinsn = prev_nonnote_insn (sinsn))
4454 set = single_set (sinsn);
4456 && SET_DEST (set) == regno_reg_rtx [regnoi])
4458 = gen_rtx_EXPR_LIST (REG_EQUIV,
4459 parm_reg_stack_loc[regnoi],
4462 && SET_DEST (set) == regno_reg_rtx [regnor])
4464 = gen_rtx_EXPR_LIST (REG_EQUIV,
4465 parm_reg_stack_loc[regnor],
4468 else if ((set = single_set (linsn)) != 0
4469 && SET_DEST (set) == parmreg)
4471 = gen_rtx_EXPR_LIST (REG_EQUIV,
4472 stack_parm, REG_NOTES (linsn));
4475 /* For pointer data type, suggest pointer register. */
4476 if (POINTER_TYPE_P (TREE_TYPE (parm)))
4477 mark_reg_pointer (parmreg,
4478 (TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm)))
4483 /* Value must be stored in the stack slot STACK_PARM
4484 during function execution. */
4486 if (promoted_mode != nominal_mode)
4488 /* Conversion is required. */
4489 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4491 emit_move_insn (tempreg, validize_mem (entry_parm));
4493 push_to_sequence (conversion_insns);
4494 entry_parm = convert_to_mode (nominal_mode, tempreg,
4495 TREE_UNSIGNED (TREE_TYPE (parm)));
4498 /* ??? This may need a big-endian conversion on sparc64. */
4499 stack_parm = change_address (stack_parm, nominal_mode,
4502 conversion_insns = get_insns ();
4507 if (entry_parm != stack_parm)
4509 if (stack_parm == 0)
4512 = assign_stack_local (GET_MODE (entry_parm),
4513 GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
4514 /* If this is a memory ref that contains aggregate components,
4515 mark it as such for cse and loop optimize. */
4516 MEM_IN_STRUCT_P (stack_parm) = aggregate;
4519 if (promoted_mode != nominal_mode)
4521 push_to_sequence (conversion_insns);
4522 emit_move_insn (validize_mem (stack_parm),
4523 validize_mem (entry_parm));
4524 conversion_insns = get_insns ();
4528 emit_move_insn (validize_mem (stack_parm),
4529 validize_mem (entry_parm));
4531 if (flag_check_memory_usage)
4533 push_to_sequence (conversion_insns);
4534 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
4535 XEXP (stack_parm, 0), ptr_mode,
4536 GEN_INT (GET_MODE_SIZE (GET_MODE
4538 TYPE_MODE (sizetype),
4539 GEN_INT (MEMORY_USE_RW),
4540 TYPE_MODE (integer_type_node));
4542 conversion_insns = get_insns ();
4545 DECL_RTL (parm) = stack_parm;
4548 /* If this "parameter" was the place where we are receiving the
4549 function's incoming structure pointer, set up the result. */
4550 if (parm == function_result_decl)
4552 tree result = DECL_RESULT (fndecl);
4553 tree restype = TREE_TYPE (result);
4556 = gen_rtx_MEM (DECL_MODE (result), DECL_RTL (parm));
4558 MEM_IN_STRUCT_P (DECL_RTL (result)) = AGGREGATE_TYPE_P (restype);
4561 if (TREE_THIS_VOLATILE (parm))
4562 MEM_VOLATILE_P (DECL_RTL (parm)) = 1;
4563 if (TREE_READONLY (parm))
4564 RTX_UNCHANGING_P (DECL_RTL (parm)) = 1;
4567 /* Output all parameter conversion instructions (possibly including calls)
4568 now that all parameters have been copied out of hard registers. */
4569 emit_insns (conversion_insns);
4571 last_parm_insn = get_last_insn ();
4573 current_function_args_size = stack_args_size.constant;
4575 /* Adjust function incoming argument size for alignment and
4578 #ifdef REG_PARM_STACK_SPACE
4579 #ifndef MAYBE_REG_PARM_STACK_SPACE
4580 current_function_args_size = MAX (current_function_args_size,
4581 REG_PARM_STACK_SPACE (fndecl));
4585 #ifdef STACK_BOUNDARY
4586 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
4588 current_function_args_size
4589 = ((current_function_args_size + STACK_BYTES - 1)
4590 / STACK_BYTES) * STACK_BYTES;
4593 #ifdef ARGS_GROW_DOWNWARD
4594 current_function_arg_offset_rtx
4595 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
4596 : expand_expr (size_binop (MINUS_EXPR, stack_args_size.var,
4597 size_int (-stack_args_size.constant)),
4598 NULL_RTX, VOIDmode, EXPAND_MEMORY_USE_BAD));
4600 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
4603 /* See how many bytes, if any, of its args a function should try to pop
4606 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
4607 current_function_args_size);
4609 /* For stdarg.h function, save info about
4610 regs and stack space used by the named args. */
4613 current_function_args_info = args_so_far;
4615 /* Set the rtx used for the function return value. Put this in its
4616 own variable so any optimizers that need this information don't have
4617 to include tree.h. Do this here so it gets done when an inlined
4618 function gets output. */
4620 current_function_return_rtx = DECL_RTL (DECL_RESULT (fndecl));
4623 /* Indicate whether REGNO is an incoming argument to the current function
4624 that was promoted to a wider mode. If so, return the RTX for the
4625 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
4626 that REGNO is promoted from and whether the promotion was signed or
4629 #ifdef PROMOTE_FUNCTION_ARGS
4632 promoted_input_arg (regno, pmode, punsignedp)
4634 enum machine_mode *pmode;
4639 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
4640 arg = TREE_CHAIN (arg))
4641 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
4642 && REGNO (DECL_INCOMING_RTL (arg)) == regno
4643 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
4645 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
4646 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
4648 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
4649 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
4650 && mode != DECL_MODE (arg))
4652 *pmode = DECL_MODE (arg);
4653 *punsignedp = unsignedp;
4654 return DECL_INCOMING_RTL (arg);
4663 /* Compute the size and offset from the start of the stacked arguments for a
4664 parm passed in mode PASSED_MODE and with type TYPE.
4666 INITIAL_OFFSET_PTR points to the current offset into the stacked
4669 The starting offset and size for this parm are returned in *OFFSET_PTR
4670 and *ARG_SIZE_PTR, respectively.
4672 IN_REGS is non-zero if the argument will be passed in registers. It will
4673 never be set if REG_PARM_STACK_SPACE is not defined.
4675 FNDECL is the function in which the argument was defined.
4677 There are two types of rounding that are done. The first, controlled by
4678 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
4679 list to be aligned to the specific boundary (in bits). This rounding
4680 affects the initial and starting offsets, but not the argument size.
4682 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
4683 optionally rounds the size of the parm to PARM_BOUNDARY. The
4684 initial offset is not affected by this rounding, while the size always
4685 is and the starting offset may be. */
4687 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
4688 initial_offset_ptr is positive because locate_and_pad_parm's
4689 callers pass in the total size of args so far as
4690 initial_offset_ptr. arg_size_ptr is always positive.*/
4693 locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
4694 initial_offset_ptr, offset_ptr, arg_size_ptr)
4695 enum machine_mode passed_mode;
4699 struct args_size *initial_offset_ptr;
4700 struct args_size *offset_ptr;
4701 struct args_size *arg_size_ptr;
4704 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
4705 enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
4706 int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
4708 #ifdef REG_PARM_STACK_SPACE
4709 /* If we have found a stack parm before we reach the end of the
4710 area reserved for registers, skip that area. */
4713 int reg_parm_stack_space = 0;
4715 #ifdef MAYBE_REG_PARM_STACK_SPACE
4716 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
4718 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
4720 if (reg_parm_stack_space > 0)
4722 if (initial_offset_ptr->var)
4724 initial_offset_ptr->var
4725 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
4726 size_int (reg_parm_stack_space));
4727 initial_offset_ptr->constant = 0;
4729 else if (initial_offset_ptr->constant < reg_parm_stack_space)
4730 initial_offset_ptr->constant = reg_parm_stack_space;
4733 #endif /* REG_PARM_STACK_SPACE */
4735 arg_size_ptr->var = 0;
4736 arg_size_ptr->constant = 0;
4738 #ifdef ARGS_GROW_DOWNWARD
4739 if (initial_offset_ptr->var)
4741 offset_ptr->constant = 0;
4742 offset_ptr->var = size_binop (MINUS_EXPR, integer_zero_node,
4743 initial_offset_ptr->var);
4747 offset_ptr->constant = - initial_offset_ptr->constant;
4748 offset_ptr->var = 0;
4750 if (where_pad != none
4751 && (TREE_CODE (sizetree) != INTEGER_CST
4752 || ((TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)))
4753 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
4754 SUB_PARM_SIZE (*offset_ptr, sizetree);
4755 if (where_pad != downward)
4756 pad_to_arg_alignment (offset_ptr, boundary);
4757 if (initial_offset_ptr->var)
4759 arg_size_ptr->var = size_binop (MINUS_EXPR,
4760 size_binop (MINUS_EXPR,
4762 initial_offset_ptr->var),
4767 arg_size_ptr->constant = (- initial_offset_ptr->constant
4768 - offset_ptr->constant);
4770 #else /* !ARGS_GROW_DOWNWARD */
4771 pad_to_arg_alignment (initial_offset_ptr, boundary);
4772 *offset_ptr = *initial_offset_ptr;
4774 #ifdef PUSH_ROUNDING
4775 if (passed_mode != BLKmode)
4776 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
4779 /* Pad_below needs the pre-rounded size to know how much to pad below
4780 so this must be done before rounding up. */
4781 if (where_pad == downward
4782 /* However, BLKmode args passed in regs have their padding done elsewhere.
4783 The stack slot must be able to hold the entire register. */
4784 && !(in_regs && passed_mode == BLKmode))
4785 pad_below (offset_ptr, passed_mode, sizetree);
4787 if (where_pad != none
4788 && (TREE_CODE (sizetree) != INTEGER_CST
4789 || ((TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)))
4790 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
4792 ADD_PARM_SIZE (*arg_size_ptr, sizetree);
4793 #endif /* ARGS_GROW_DOWNWARD */
4796 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
4797 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
4800 pad_to_arg_alignment (offset_ptr, boundary)
4801 struct args_size *offset_ptr;
4804 int boundary_in_bytes = boundary / BITS_PER_UNIT;
4806 if (boundary > BITS_PER_UNIT)
4808 if (offset_ptr->var)
4811 #ifdef ARGS_GROW_DOWNWARD
4816 (ARGS_SIZE_TREE (*offset_ptr),
4817 boundary / BITS_PER_UNIT);
4818 offset_ptr->constant = 0; /*?*/
4821 offset_ptr->constant =
4822 #ifdef ARGS_GROW_DOWNWARD
4823 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
4825 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
4830 #ifndef ARGS_GROW_DOWNWARD
4832 pad_below (offset_ptr, passed_mode, sizetree)
4833 struct args_size *offset_ptr;
4834 enum machine_mode passed_mode;
4837 if (passed_mode != BLKmode)
4839 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
4840 offset_ptr->constant
4841 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
4842 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
4843 - GET_MODE_SIZE (passed_mode));
4847 if (TREE_CODE (sizetree) != INTEGER_CST
4848 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
4850 /* Round the size up to multiple of PARM_BOUNDARY bits. */
4851 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
4853 ADD_PARM_SIZE (*offset_ptr, s2);
4854 SUB_PARM_SIZE (*offset_ptr, sizetree);
4860 #ifdef ARGS_GROW_DOWNWARD
4862 round_down (value, divisor)
4866 return size_binop (MULT_EXPR,
4867 size_binop (FLOOR_DIV_EXPR, value, size_int (divisor)),
4868 size_int (divisor));
4872 /* Walk the tree of blocks describing the binding levels within a function
4873 and warn about uninitialized variables.
4874 This is done after calling flow_analysis and before global_alloc
4875 clobbers the pseudo-regs to hard regs. */
4878 uninitialized_vars_warning (block)
4881 register tree decl, sub;
4882 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
4884 if (TREE_CODE (decl) == VAR_DECL
4885 /* These warnings are unreliable for and aggregates
4886 because assigning the fields one by one can fail to convince
4887 flow.c that the entire aggregate was initialized.
4888 Unions are troublesome because members may be shorter. */
4889 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
4890 && DECL_RTL (decl) != 0
4891 && GET_CODE (DECL_RTL (decl)) == REG
4892 && regno_uninitialized (REGNO (DECL_RTL (decl))))
4893 warning_with_decl (decl,
4894 "`%s' might be used uninitialized in this function");
4895 if (TREE_CODE (decl) == VAR_DECL
4896 && DECL_RTL (decl) != 0
4897 && GET_CODE (DECL_RTL (decl)) == REG
4898 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
4899 warning_with_decl (decl,
4900 "variable `%s' might be clobbered by `longjmp' or `vfork'");
4902 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
4903 uninitialized_vars_warning (sub);
4906 /* Do the appropriate part of uninitialized_vars_warning
4907 but for arguments instead of local variables. */
4910 setjmp_args_warning ()
4913 for (decl = DECL_ARGUMENTS (current_function_decl);
4914 decl; decl = TREE_CHAIN (decl))
4915 if (DECL_RTL (decl) != 0
4916 && GET_CODE (DECL_RTL (decl)) == REG
4917 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
4918 warning_with_decl (decl, "argument `%s' might be clobbered by `longjmp' or `vfork'");
4921 /* If this function call setjmp, put all vars into the stack
4922 unless they were declared `register'. */
4925 setjmp_protect (block)
4928 register tree decl, sub;
4929 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
4930 if ((TREE_CODE (decl) == VAR_DECL
4931 || TREE_CODE (decl) == PARM_DECL)
4932 && DECL_RTL (decl) != 0
4933 && (GET_CODE (DECL_RTL (decl)) == REG
4934 || (GET_CODE (DECL_RTL (decl)) == MEM
4935 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
4936 /* If this variable came from an inline function, it must be
4937 that its life doesn't overlap the setjmp. If there was a
4938 setjmp in the function, it would already be in memory. We
4939 must exclude such variable because their DECL_RTL might be
4940 set to strange things such as virtual_stack_vars_rtx. */
4941 && ! DECL_FROM_INLINE (decl)
4943 #ifdef NON_SAVING_SETJMP
4944 /* If longjmp doesn't restore the registers,
4945 don't put anything in them. */
4949 ! DECL_REGISTER (decl)))
4950 put_var_into_stack (decl);
4951 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
4952 setjmp_protect (sub);
4955 /* Like the previous function, but for args instead of local variables. */
4958 setjmp_protect_args ()
4961 for (decl = DECL_ARGUMENTS (current_function_decl);
4962 decl; decl = TREE_CHAIN (decl))
4963 if ((TREE_CODE (decl) == VAR_DECL
4964 || TREE_CODE (decl) == PARM_DECL)
4965 && DECL_RTL (decl) != 0
4966 && (GET_CODE (DECL_RTL (decl)) == REG
4967 || (GET_CODE (DECL_RTL (decl)) == MEM
4968 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
4970 /* If longjmp doesn't restore the registers,
4971 don't put anything in them. */
4972 #ifdef NON_SAVING_SETJMP
4976 ! DECL_REGISTER (decl)))
4977 put_var_into_stack (decl);
4980 /* Return the context-pointer register corresponding to DECL,
4981 or 0 if it does not need one. */
4984 lookup_static_chain (decl)
4987 tree context = decl_function_context (decl);
4991 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
4994 /* We treat inline_function_decl as an alias for the current function
4995 because that is the inline function whose vars, types, etc.
4996 are being merged into the current function.
4997 See expand_inline_function. */
4998 if (context == current_function_decl || context == inline_function_decl)
4999 return virtual_stack_vars_rtx;
5001 for (link = context_display; link; link = TREE_CHAIN (link))
5002 if (TREE_PURPOSE (link) == context)
5003 return RTL_EXPR_RTL (TREE_VALUE (link));
5008 /* Convert a stack slot address ADDR for variable VAR
5009 (from a containing function)
5010 into an address valid in this function (using a static chain). */
5013 fix_lexical_addr (addr, var)
5018 HOST_WIDE_INT displacement;
5019 tree context = decl_function_context (var);
5020 struct function *fp;
5023 /* If this is the present function, we need not do anything. */
5024 if (context == current_function_decl || context == inline_function_decl)
5027 for (fp = outer_function_chain; fp; fp = fp->next)
5028 if (fp->decl == context)
5034 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5035 addr = XEXP (XEXP (addr, 0), 0);
5037 /* Decode given address as base reg plus displacement. */
5038 if (GET_CODE (addr) == REG)
5039 basereg = addr, displacement = 0;
5040 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5041 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5045 /* We accept vars reached via the containing function's
5046 incoming arg pointer and via its stack variables pointer. */
5047 if (basereg == fp->internal_arg_pointer)
5049 /* If reached via arg pointer, get the arg pointer value
5050 out of that function's stack frame.
5052 There are two cases: If a separate ap is needed, allocate a
5053 slot in the outer function for it and dereference it that way.
5054 This is correct even if the real ap is actually a pseudo.
5055 Otherwise, just adjust the offset from the frame pointer to
5058 #ifdef NEED_SEPARATE_AP
5061 if (fp->arg_pointer_save_area == 0)
5062 fp->arg_pointer_save_area
5063 = assign_outer_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0, fp);
5065 addr = fix_lexical_addr (XEXP (fp->arg_pointer_save_area, 0), var);
5066 addr = memory_address (Pmode, addr);
5068 base = copy_to_reg (gen_rtx_MEM (Pmode, addr));
5070 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5071 base = lookup_static_chain (var);
5075 else if (basereg == virtual_stack_vars_rtx)
5077 /* This is the same code as lookup_static_chain, duplicated here to
5078 avoid an extra call to decl_function_context. */
5081 for (link = context_display; link; link = TREE_CHAIN (link))
5082 if (TREE_PURPOSE (link) == context)
5084 base = RTL_EXPR_RTL (TREE_VALUE (link));
5092 /* Use same offset, relative to appropriate static chain or argument
5094 return plus_constant (base, displacement);
5097 /* Return the address of the trampoline for entering nested fn FUNCTION.
5098 If necessary, allocate a trampoline (in the stack frame)
5099 and emit rtl to initialize its contents (at entry to this function). */
5102 trampoline_address (function)
5108 struct function *fp;
5111 /* Find an existing trampoline and return it. */
5112 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5113 if (TREE_PURPOSE (link) == function)
5115 round_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5117 for (fp = outer_function_chain; fp; fp = fp->next)
5118 for (link = fp->trampoline_list; link; link = TREE_CHAIN (link))
5119 if (TREE_PURPOSE (link) == function)
5121 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5123 return round_trampoline_addr (tramp);
5126 /* None exists; we must make one. */
5128 /* Find the `struct function' for the function containing FUNCTION. */
5130 fn_context = decl_function_context (function);
5131 if (fn_context != current_function_decl
5132 && fn_context != inline_function_decl)
5133 for (fp = outer_function_chain; fp; fp = fp->next)
5134 if (fp->decl == fn_context)
5137 /* Allocate run-time space for this trampoline
5138 (usually in the defining function's stack frame). */
5139 #ifdef ALLOCATE_TRAMPOLINE
5140 tramp = ALLOCATE_TRAMPOLINE (fp);
5142 /* If rounding needed, allocate extra space
5143 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5144 #ifdef TRAMPOLINE_ALIGNMENT
5145 #define TRAMPOLINE_REAL_SIZE \
5146 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5148 #define TRAMPOLINE_REAL_SIZE (TRAMPOLINE_SIZE)
5151 tramp = assign_outer_stack_local (BLKmode, TRAMPOLINE_REAL_SIZE, 0, fp);
5153 tramp = assign_stack_local (BLKmode, TRAMPOLINE_REAL_SIZE, 0);
5156 /* Record the trampoline for reuse and note it for later initialization
5157 by expand_function_end. */
5160 push_obstacks (fp->function_maybepermanent_obstack,
5161 fp->function_maybepermanent_obstack);
5162 rtlexp = make_node (RTL_EXPR);
5163 RTL_EXPR_RTL (rtlexp) = tramp;
5164 fp->trampoline_list = tree_cons (function, rtlexp, fp->trampoline_list);
5169 /* Make the RTL_EXPR node temporary, not momentary, so that the
5170 trampoline_list doesn't become garbage. */
5171 int momentary = suspend_momentary ();
5172 rtlexp = make_node (RTL_EXPR);
5173 resume_momentary (momentary);
5175 RTL_EXPR_RTL (rtlexp) = tramp;
5176 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5179 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5180 return round_trampoline_addr (tramp);
5183 /* Given a trampoline address,
5184 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5187 round_trampoline_addr (tramp)
5190 #ifdef TRAMPOLINE_ALIGNMENT
5191 /* Round address up to desired boundary. */
5192 rtx temp = gen_reg_rtx (Pmode);
5193 temp = expand_binop (Pmode, add_optab, tramp,
5194 GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1),
5195 temp, 0, OPTAB_LIB_WIDEN);
5196 tramp = expand_binop (Pmode, and_optab, temp,
5197 GEN_INT (- TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT),
5198 temp, 0, OPTAB_LIB_WIDEN);
5203 /* The functions identify_blocks and reorder_blocks provide a way to
5204 reorder the tree of BLOCK nodes, for optimizers that reshuffle or
5205 duplicate portions of the RTL code. Call identify_blocks before
5206 changing the RTL, and call reorder_blocks after. */
5208 /* Put all this function's BLOCK nodes including those that are chained
5209 onto the first block into a vector, and return it.
5210 Also store in each NOTE for the beginning or end of a block
5211 the index of that block in the vector.
5212 The arguments are BLOCK, the chain of top-level blocks of the function,
5213 and INSNS, the insn chain of the function. */
5216 identify_blocks (block, insns)
5224 int next_block_number = 1;
5225 int current_block_number = 1;
5231 n_blocks = all_blocks (block, 0);
5232 block_vector = (tree *) xmalloc (n_blocks * sizeof (tree));
5233 block_stack = (int *) alloca (n_blocks * sizeof (int));
5235 all_blocks (block, block_vector);
5237 for (insn = insns; insn; insn = NEXT_INSN (insn))
5238 if (GET_CODE (insn) == NOTE)
5240 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5242 block_stack[depth++] = current_block_number;
5243 current_block_number = next_block_number;
5244 NOTE_BLOCK_NUMBER (insn) = next_block_number++;
5246 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5248 NOTE_BLOCK_NUMBER (insn) = current_block_number;
5249 current_block_number = block_stack[--depth];
5253 if (n_blocks != next_block_number)
5256 return block_vector;
5259 /* Given BLOCK_VECTOR which was returned by identify_blocks,
5260 and a revised instruction chain, rebuild the tree structure
5261 of BLOCK nodes to correspond to the new order of RTL.
5262 The new block tree is inserted below TOP_BLOCK.
5263 Returns the current top-level block. */
5266 reorder_blocks (block_vector, block, insns)
5271 tree current_block = block;
5274 if (block_vector == 0)
5277 /* Prune the old trees away, so that it doesn't get in the way. */
5278 BLOCK_SUBBLOCKS (current_block) = 0;
5279 BLOCK_CHAIN (current_block) = 0;
5281 for (insn = insns; insn; insn = NEXT_INSN (insn))
5282 if (GET_CODE (insn) == NOTE)
5284 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5286 tree block = block_vector[NOTE_BLOCK_NUMBER (insn)];
5287 /* If we have seen this block before, copy it. */
5288 if (TREE_ASM_WRITTEN (block))
5289 block = copy_node (block);
5290 BLOCK_SUBBLOCKS (block) = 0;
5291 TREE_ASM_WRITTEN (block) = 1;
5292 BLOCK_SUPERCONTEXT (block) = current_block;
5293 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
5294 BLOCK_SUBBLOCKS (current_block) = block;
5295 current_block = block;
5296 NOTE_SOURCE_FILE (insn) = 0;
5298 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5300 BLOCK_SUBBLOCKS (current_block)
5301 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5302 current_block = BLOCK_SUPERCONTEXT (current_block);
5303 NOTE_SOURCE_FILE (insn) = 0;
5307 BLOCK_SUBBLOCKS (current_block)
5308 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5309 return current_block;
5312 /* Reverse the order of elements in the chain T of blocks,
5313 and return the new head of the chain (old last element). */
5319 register tree prev = 0, decl, next;
5320 for (decl = t; decl; decl = next)
5322 next = BLOCK_CHAIN (decl);
5323 BLOCK_CHAIN (decl) = prev;
5329 /* Count the subblocks of the list starting with BLOCK, and list them
5330 all into the vector VECTOR. Also clear TREE_ASM_WRITTEN in all
5334 all_blocks (block, vector)
5342 TREE_ASM_WRITTEN (block) = 0;
5344 /* Record this block. */
5346 vector[n_blocks] = block;
5350 /* Record the subblocks, and their subblocks... */
5351 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
5352 vector ? vector + n_blocks : 0);
5353 block = BLOCK_CHAIN (block);
5359 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
5360 and initialize static variables for generating RTL for the statements
5364 init_function_start (subr, filename, line)
5369 init_stmt_for_function ();
5371 cse_not_expected = ! optimize;
5373 /* Caller save not needed yet. */
5374 caller_save_needed = 0;
5376 /* No stack slots have been made yet. */
5377 stack_slot_list = 0;
5379 /* There is no stack slot for handling nonlocal gotos. */
5380 nonlocal_goto_handler_slot = 0;
5381 nonlocal_goto_stack_level = 0;
5383 /* No labels have been declared for nonlocal use. */
5384 nonlocal_labels = 0;
5386 /* No function calls so far in this function. */
5387 function_call_count = 0;
5389 /* No parm regs have been allocated.
5390 (This is important for output_inline_function.) */
5391 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
5393 /* Initialize the RTL mechanism. */
5396 /* Initialize the queue of pending postincrement and postdecrements,
5397 and some other info in expr.c. */
5400 /* We haven't done register allocation yet. */
5403 init_const_rtx_hash_table ();
5405 current_function_name = (*decl_printable_name) (subr, 2);
5407 /* Nonzero if this is a nested function that uses a static chain. */
5409 current_function_needs_context
5410 = (decl_function_context (current_function_decl) != 0
5411 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
5413 /* Set if a call to setjmp is seen. */
5414 current_function_calls_setjmp = 0;
5416 /* Set if a call to longjmp is seen. */
5417 current_function_calls_longjmp = 0;
5419 current_function_calls_alloca = 0;
5420 current_function_has_nonlocal_label = 0;
5421 current_function_has_nonlocal_goto = 0;
5422 current_function_contains_functions = 0;
5423 current_function_is_thunk = 0;
5425 current_function_returns_pcc_struct = 0;
5426 current_function_returns_struct = 0;
5427 current_function_epilogue_delay_list = 0;
5428 current_function_uses_const_pool = 0;
5429 current_function_uses_pic_offset_table = 0;
5430 current_function_cannot_inline = 0;
5432 /* We have not yet needed to make a label to jump to for tail-recursion. */
5433 tail_recursion_label = 0;
5435 /* We haven't had a need to make a save area for ap yet. */
5437 arg_pointer_save_area = 0;
5439 /* No stack slots allocated yet. */
5442 /* No SAVE_EXPRs in this function yet. */
5445 /* No RTL_EXPRs in this function yet. */
5448 /* Set up to allocate temporaries. */
5451 /* Within function body, compute a type's size as soon it is laid out. */
5452 immediate_size_expand++;
5454 /* We haven't made any trampolines for this function yet. */
5455 trampoline_list = 0;
5457 init_pending_stack_adjust ();
5458 inhibit_defer_pop = 0;
5460 current_function_outgoing_args_size = 0;
5462 /* Prevent ever trying to delete the first instruction of a function.
5463 Also tell final how to output a linenum before the function prologue.
5464 Note linenums could be missing, e.g. when compiling a Java .class file. */
5466 emit_line_note (filename, line);
5468 /* Make sure first insn is a note even if we don't want linenums.
5469 This makes sure the first insn will never be deleted.
5470 Also, final expects a note to appear there. */
5471 emit_note (NULL_PTR, NOTE_INSN_DELETED);
5473 /* Set flags used by final.c. */
5474 if (aggregate_value_p (DECL_RESULT (subr)))
5476 #ifdef PCC_STATIC_STRUCT_RETURN
5477 current_function_returns_pcc_struct = 1;
5479 current_function_returns_struct = 1;
5482 /* Warn if this value is an aggregate type,
5483 regardless of which calling convention we are using for it. */
5484 if (warn_aggregate_return
5485 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
5486 warning ("function returns an aggregate");
5488 current_function_returns_pointer
5489 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
5491 /* Indicate that we need to distinguish between the return value of the
5492 present function and the return value of a function being called. */
5493 rtx_equal_function_value_matters = 1;
5495 /* Indicate that we have not instantiated virtual registers yet. */
5496 virtuals_instantiated = 0;
5498 /* Indicate we have no need of a frame pointer yet. */
5499 frame_pointer_needed = 0;
5501 /* By default assume not varargs or stdarg. */
5502 current_function_varargs = 0;
5503 current_function_stdarg = 0;
5506 /* Indicate that the current function uses extra args
5507 not explicitly mentioned in the argument list in any fashion. */
5512 current_function_varargs = 1;
5515 /* Expand a call to __main at the beginning of a possible main function. */
5517 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
5518 #undef HAS_INIT_SECTION
5519 #define HAS_INIT_SECTION
5523 expand_main_function ()
5525 #if !defined (HAS_INIT_SECTION)
5526 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, NAME__MAIN), 0,
5528 #endif /* not HAS_INIT_SECTION */
5531 extern struct obstack permanent_obstack;
5533 /* Start the RTL for a new function, and set variables used for
5535 SUBR is the FUNCTION_DECL node.
5536 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
5537 the function's parameters, which must be run at any return statement. */
5540 expand_function_start (subr, parms_have_cleanups)
5542 int parms_have_cleanups;
5546 rtx last_ptr = NULL_RTX;
5548 /* Make sure volatile mem refs aren't considered
5549 valid operands of arithmetic insns. */
5550 init_recog_no_volatile ();
5552 current_function_instrument_entry_exit
5553 = (flag_instrument_function_entry_exit
5554 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
5556 /* If function gets a static chain arg, store it in the stack frame.
5557 Do this first, so it gets the first stack slot offset. */
5558 if (current_function_needs_context)
5560 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
5562 /* Delay copying static chain if it is not a register to avoid
5563 conflicts with regs used for parameters. */
5564 if (! SMALL_REGISTER_CLASSES
5565 || GET_CODE (static_chain_incoming_rtx) == REG)
5566 emit_move_insn (last_ptr, static_chain_incoming_rtx);
5569 /* If the parameters of this function need cleaning up, get a label
5570 for the beginning of the code which executes those cleanups. This must
5571 be done before doing anything with return_label. */
5572 if (parms_have_cleanups)
5573 cleanup_label = gen_label_rtx ();
5577 /* Make the label for return statements to jump to, if this machine
5578 does not have a one-instruction return and uses an epilogue,
5579 or if it returns a structure, or if it has parm cleanups. */
5581 if (cleanup_label == 0 && HAVE_return
5582 && ! current_function_instrument_entry_exit
5583 && ! current_function_returns_pcc_struct
5584 && ! (current_function_returns_struct && ! optimize))
5587 return_label = gen_label_rtx ();
5589 return_label = gen_label_rtx ();
5592 /* Initialize rtx used to return the value. */
5593 /* Do this before assign_parms so that we copy the struct value address
5594 before any library calls that assign parms might generate. */
5596 /* Decide whether to return the value in memory or in a register. */
5597 if (aggregate_value_p (DECL_RESULT (subr)))
5599 /* Returning something that won't go in a register. */
5600 register rtx value_address = 0;
5602 #ifdef PCC_STATIC_STRUCT_RETURN
5603 if (current_function_returns_pcc_struct)
5605 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
5606 value_address = assemble_static_space (size);
5611 /* Expect to be passed the address of a place to store the value.
5612 If it is passed as an argument, assign_parms will take care of
5614 if (struct_value_incoming_rtx)
5616 value_address = gen_reg_rtx (Pmode);
5617 emit_move_insn (value_address, struct_value_incoming_rtx);
5622 DECL_RTL (DECL_RESULT (subr))
5623 = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
5624 MEM_IN_STRUCT_P (DECL_RTL (DECL_RESULT (subr)))
5625 = AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
5628 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
5629 /* If return mode is void, this decl rtl should not be used. */
5630 DECL_RTL (DECL_RESULT (subr)) = 0;
5631 else if (parms_have_cleanups || current_function_instrument_entry_exit)
5633 /* If function will end with cleanup code for parms,
5634 compute the return values into a pseudo reg,
5635 which we will copy into the true return register
5636 after the cleanups are done. */
5638 enum machine_mode mode = DECL_MODE (DECL_RESULT (subr));
5640 #ifdef PROMOTE_FUNCTION_RETURN
5641 tree type = TREE_TYPE (DECL_RESULT (subr));
5642 int unsignedp = TREE_UNSIGNED (type);
5644 mode = promote_mode (type, mode, &unsignedp, 1);
5647 DECL_RTL (DECL_RESULT (subr)) = gen_reg_rtx (mode);
5650 /* Scalar, returned in a register. */
5652 #ifdef FUNCTION_OUTGOING_VALUE
5653 DECL_RTL (DECL_RESULT (subr))
5654 = FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (subr)), subr);
5656 DECL_RTL (DECL_RESULT (subr))
5657 = FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (subr)), subr);
5660 /* Mark this reg as the function's return value. */
5661 if (GET_CODE (DECL_RTL (DECL_RESULT (subr))) == REG)
5663 REG_FUNCTION_VALUE_P (DECL_RTL (DECL_RESULT (subr))) = 1;
5664 /* Needed because we may need to move this to memory
5665 in case it's a named return value whose address is taken. */
5666 DECL_REGISTER (DECL_RESULT (subr)) = 1;
5670 /* Initialize rtx for parameters and local variables.
5671 In some cases this requires emitting insns. */
5673 assign_parms (subr, 0);
5675 /* Copy the static chain now if it wasn't a register. The delay is to
5676 avoid conflicts with the parameter passing registers. */
5678 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
5679 if (GET_CODE (static_chain_incoming_rtx) != REG)
5680 emit_move_insn (last_ptr, static_chain_incoming_rtx);
5682 /* The following was moved from init_function_start.
5683 The move is supposed to make sdb output more accurate. */
5684 /* Indicate the beginning of the function body,
5685 as opposed to parm setup. */
5686 emit_note (NULL_PTR, NOTE_INSN_FUNCTION_BEG);
5688 /* If doing stupid allocation, mark parms as born here. */
5690 if (GET_CODE (get_last_insn ()) != NOTE)
5691 emit_note (NULL_PTR, NOTE_INSN_DELETED);
5692 parm_birth_insn = get_last_insn ();
5696 for (i = LAST_VIRTUAL_REGISTER + 1; i < max_parm_reg; i++)
5697 use_variable (regno_reg_rtx[i]);
5699 if (current_function_internal_arg_pointer != virtual_incoming_args_rtx)
5700 use_variable (current_function_internal_arg_pointer);
5703 context_display = 0;
5704 if (current_function_needs_context)
5706 /* Fetch static chain values for containing functions. */
5707 tem = decl_function_context (current_function_decl);
5708 /* If not doing stupid register allocation copy the static chain
5709 pointer into a pseudo. If we have small register classes, copy
5710 the value from memory if static_chain_incoming_rtx is a REG. If
5711 we do stupid register allocation, we use the stack address
5713 if (tem && ! obey_regdecls)
5715 /* If the static chain originally came in a register, put it back
5716 there, then move it out in the next insn. The reason for
5717 this peculiar code is to satisfy function integration. */
5718 if (SMALL_REGISTER_CLASSES
5719 && GET_CODE (static_chain_incoming_rtx) == REG)
5720 emit_move_insn (static_chain_incoming_rtx, last_ptr);
5721 last_ptr = copy_to_reg (static_chain_incoming_rtx);
5726 tree rtlexp = make_node (RTL_EXPR);
5728 RTL_EXPR_RTL (rtlexp) = last_ptr;
5729 context_display = tree_cons (tem, rtlexp, context_display);
5730 tem = decl_function_context (tem);
5733 /* Chain thru stack frames, assuming pointer to next lexical frame
5734 is found at the place we always store it. */
5735 #ifdef FRAME_GROWS_DOWNWARD
5736 last_ptr = plus_constant (last_ptr, - GET_MODE_SIZE (Pmode));
5738 last_ptr = copy_to_reg (gen_rtx_MEM (Pmode,
5739 memory_address (Pmode, last_ptr)));
5741 /* If we are not optimizing, ensure that we know that this
5742 piece of context is live over the entire function. */
5744 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
5749 if (current_function_instrument_entry_exit)
5751 rtx fun = DECL_RTL (current_function_decl);
5752 if (GET_CODE (fun) == MEM)
5753 fun = XEXP (fun, 0);
5756 emit_library_call (profile_function_entry_libfunc, 0, VOIDmode, 2,
5758 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
5760 hard_frame_pointer_rtx),
5764 /* After the display initializations is where the tail-recursion label
5765 should go, if we end up needing one. Ensure we have a NOTE here
5766 since some things (like trampolines) get placed before this. */
5767 tail_recursion_reentry = emit_note (NULL_PTR, NOTE_INSN_DELETED);
5769 /* Evaluate now the sizes of any types declared among the arguments. */
5770 for (tem = nreverse (get_pending_sizes ()); tem; tem = TREE_CHAIN (tem))
5772 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode,
5773 EXPAND_MEMORY_USE_BAD);
5774 /* Flush the queue in case this parameter declaration has
5779 /* Make sure there is a line number after the function entry setup code. */
5780 force_next_line_note ();
5783 /* Generate RTL for the end of the current function.
5784 FILENAME and LINE are the current position in the source file.
5786 It is up to language-specific callers to do cleanups for parameters--
5787 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
5790 expand_function_end (filename, line, end_bindings)
5798 #ifdef TRAMPOLINE_TEMPLATE
5799 static rtx initial_trampoline;
5802 #ifdef NON_SAVING_SETJMP
5803 /* Don't put any variables in registers if we call setjmp
5804 on a machine that fails to restore the registers. */
5805 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
5807 if (DECL_INITIAL (current_function_decl) != error_mark_node)
5808 setjmp_protect (DECL_INITIAL (current_function_decl));
5810 setjmp_protect_args ();
5814 /* Save the argument pointer if a save area was made for it. */
5815 if (arg_pointer_save_area)
5817 rtx x = gen_move_insn (arg_pointer_save_area, virtual_incoming_args_rtx);
5818 emit_insn_before (x, tail_recursion_reentry);
5821 /* Initialize any trampolines required by this function. */
5822 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5824 tree function = TREE_PURPOSE (link);
5825 rtx context = lookup_static_chain (function);
5826 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
5827 #ifdef TRAMPOLINE_TEMPLATE
5832 #ifdef TRAMPOLINE_TEMPLATE
5833 /* First make sure this compilation has a template for
5834 initializing trampolines. */
5835 if (initial_trampoline == 0)
5837 end_temporary_allocation ();
5839 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
5840 resume_temporary_allocation ();
5844 /* Generate insns to initialize the trampoline. */
5846 tramp = round_trampoline_addr (XEXP (tramp, 0));
5847 #ifdef TRAMPOLINE_TEMPLATE
5848 blktramp = change_address (initial_trampoline, BLKmode, tramp);
5849 emit_block_move (blktramp, initial_trampoline,
5850 GEN_INT (TRAMPOLINE_SIZE),
5851 TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
5853 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
5857 /* Put those insns at entry to the containing function (this one). */
5858 emit_insns_before (seq, tail_recursion_reentry);
5861 /* If we are doing stack checking and this function makes calls,
5862 do a stack probe at the start of the function to ensure we have enough
5863 space for another stack frame. */
5864 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
5868 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
5869 if (GET_CODE (insn) == CALL_INSN)
5872 probe_stack_range (STACK_CHECK_PROTECT,
5873 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
5876 emit_insns_before (seq, tail_recursion_reentry);
5881 /* Warn about unused parms if extra warnings were specified. */
5882 if (warn_unused && extra_warnings)
5886 for (decl = DECL_ARGUMENTS (current_function_decl);
5887 decl; decl = TREE_CHAIN (decl))
5888 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
5889 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
5890 warning_with_decl (decl, "unused parameter `%s'");
5893 /* Delete handlers for nonlocal gotos if nothing uses them. */
5894 if (nonlocal_goto_handler_slot != 0 && !current_function_has_nonlocal_label)
5897 /* End any sequences that failed to be closed due to syntax errors. */
5898 while (in_sequence_p ())
5901 /* Outside function body, can't compute type's actual size
5902 until next function's body starts. */
5903 immediate_size_expand--;
5905 /* If doing stupid register allocation,
5906 mark register parms as dying here. */
5911 for (i = LAST_VIRTUAL_REGISTER + 1; i < max_parm_reg; i++)
5912 use_variable (regno_reg_rtx[i]);
5914 /* Likewise for the regs of all the SAVE_EXPRs in the function. */
5916 for (tem = save_expr_regs; tem; tem = XEXP (tem, 1))
5918 use_variable (XEXP (tem, 0));
5919 use_variable_after (XEXP (tem, 0), parm_birth_insn);
5922 if (current_function_internal_arg_pointer != virtual_incoming_args_rtx)
5923 use_variable (current_function_internal_arg_pointer);
5926 clear_pending_stack_adjust ();
5927 do_pending_stack_adjust ();
5929 /* Mark the end of the function body.
5930 If control reaches this insn, the function can drop through
5931 without returning a value. */
5932 emit_note (NULL_PTR, NOTE_INSN_FUNCTION_END);
5934 /* Must mark the last line number note in the function, so that the test
5935 coverage code can avoid counting the last line twice. This just tells
5936 the code to ignore the immediately following line note, since there
5937 already exists a copy of this note somewhere above. This line number
5938 note is still needed for debugging though, so we can't delete it. */
5939 if (flag_test_coverage)
5940 emit_note (NULL_PTR, NOTE_REPEATED_LINE_NUMBER);
5942 /* Output a linenumber for the end of the function.
5943 SDB depends on this. */
5944 emit_line_note_force (filename, line);
5946 /* Output the label for the actual return from the function,
5947 if one is expected. This happens either because a function epilogue
5948 is used instead of a return instruction, or because a return was done
5949 with a goto in order to run local cleanups, or because of pcc-style
5950 structure returning. */
5953 emit_label (return_label);
5955 /* C++ uses this. */
5957 expand_end_bindings (0, 0, 0);
5959 /* Now handle any leftover exception regions that may have been
5960 created for the parameters. */
5962 rtx last = get_last_insn ();
5965 expand_leftover_cleanups ();
5967 /* If the above emitted any code, may sure we jump around it. */
5968 if (last != get_last_insn ())
5970 label = gen_label_rtx ();
5971 last = emit_jump_insn_after (gen_jump (label), last);
5972 last = emit_barrier_after (last);
5977 if (current_function_instrument_entry_exit)
5979 rtx fun = DECL_RTL (current_function_decl);
5980 if (GET_CODE (fun) == MEM)
5981 fun = XEXP (fun, 0);
5984 emit_library_call (profile_function_exit_libfunc, 0, VOIDmode, 2,
5986 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
5988 hard_frame_pointer_rtx),
5992 /* If we had calls to alloca, and this machine needs
5993 an accurate stack pointer to exit the function,
5994 insert some code to save and restore the stack pointer. */
5995 #ifdef EXIT_IGNORE_STACK
5996 if (! EXIT_IGNORE_STACK)
5998 if (current_function_calls_alloca)
6002 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
6003 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
6006 /* If scalar return value was computed in a pseudo-reg,
6007 copy that to the hard return register. */
6008 if (DECL_RTL (DECL_RESULT (current_function_decl)) != 0
6009 && GET_CODE (DECL_RTL (DECL_RESULT (current_function_decl))) == REG
6010 && (REGNO (DECL_RTL (DECL_RESULT (current_function_decl)))
6011 >= FIRST_PSEUDO_REGISTER))
6013 rtx real_decl_result;
6015 #ifdef FUNCTION_OUTGOING_VALUE
6017 = FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl)),
6018 current_function_decl);
6021 = FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl)),
6022 current_function_decl);
6024 REG_FUNCTION_VALUE_P (real_decl_result) = 1;
6025 /* If this is a BLKmode structure being returned in registers, then use
6026 the mode computed in expand_return. */
6027 if (GET_MODE (real_decl_result) == BLKmode)
6028 PUT_MODE (real_decl_result,
6029 GET_MODE (DECL_RTL (DECL_RESULT (current_function_decl))));
6030 emit_move_insn (real_decl_result,
6031 DECL_RTL (DECL_RESULT (current_function_decl)));
6032 emit_insn (gen_rtx_USE (VOIDmode, real_decl_result));
6034 /* The delay slot scheduler assumes that current_function_return_rtx
6035 holds the hard register containing the return value, not a temporary
6037 current_function_return_rtx = real_decl_result;
6040 /* If returning a structure, arrange to return the address of the value
6041 in a place where debuggers expect to find it.
6043 If returning a structure PCC style,
6044 the caller also depends on this value.
6045 And current_function_returns_pcc_struct is not necessarily set. */
6046 if (current_function_returns_struct
6047 || current_function_returns_pcc_struct)
6049 rtx value_address = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
6050 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
6051 #ifdef FUNCTION_OUTGOING_VALUE
6053 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
6054 current_function_decl);
6057 = FUNCTION_VALUE (build_pointer_type (type),
6058 current_function_decl);
6061 /* Mark this as a function return value so integrate will delete the
6062 assignment and USE below when inlining this function. */
6063 REG_FUNCTION_VALUE_P (outgoing) = 1;
6065 emit_move_insn (outgoing, value_address);
6066 use_variable (outgoing);
6069 /* If this is an implementation of __throw, do what's necessary to
6070 communicate between __builtin_eh_return and the epilogue. */
6071 expand_eh_return ();
6073 /* Output a return insn if we are using one.
6074 Otherwise, let the rtl chain end here, to drop through
6075 into the epilogue. */
6080 emit_jump_insn (gen_return ());
6085 /* Fix up any gotos that jumped out to the outermost
6086 binding level of the function.
6087 Must follow emitting RETURN_LABEL. */
6089 /* If you have any cleanups to do at this point,
6090 and they need to create temporary variables,
6091 then you will lose. */
6092 expand_fixups (get_insns ());
6095 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
6097 static int *prologue;
6098 static int *epilogue;
6100 /* Create an array that records the INSN_UIDs of INSNS (either a sequence
6101 or a single insn). */
6103 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
6105 record_insns (insns)
6110 if (GET_CODE (insns) == SEQUENCE)
6112 int len = XVECLEN (insns, 0);
6113 vec = (int *) oballoc ((len + 1) * sizeof (int));
6116 vec[len] = INSN_UID (XVECEXP (insns, 0, len));
6120 vec = (int *) oballoc (2 * sizeof (int));
6121 vec[0] = INSN_UID (insns);
6127 /* Determine how many INSN_UIDs in VEC are part of INSN. */
6130 contains (insn, vec)
6136 if (GET_CODE (insn) == INSN
6137 && GET_CODE (PATTERN (insn)) == SEQUENCE)
6140 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
6141 for (j = 0; vec[j]; j++)
6142 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == vec[j])
6148 for (j = 0; vec[j]; j++)
6149 if (INSN_UID (insn) == vec[j])
6154 #endif /* HAVE_prologue || HAVE_epilogue */
6156 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
6157 this into place with notes indicating where the prologue ends and where
6158 the epilogue begins. Update the basic block information when possible. */
6161 thread_prologue_and_epilogue_insns (f)
6164 #ifdef HAVE_prologue
6169 /* The first insn (a NOTE_INSN_DELETED) is followed by zero or more
6170 prologue insns and a NOTE_INSN_PROLOGUE_END. */
6171 emit_note_after (NOTE_INSN_PROLOGUE_END, f);
6172 seq = gen_prologue ();
6173 head = emit_insn_after (seq, f);
6175 /* Include the new prologue insns in the first block. Ignore them
6176 if they form a basic block unto themselves. */
6177 if (basic_block_head && n_basic_blocks
6178 && GET_CODE (basic_block_head[0]) != CODE_LABEL)
6179 basic_block_head[0] = NEXT_INSN (f);
6181 /* Retain a map of the prologue insns. */
6182 prologue = record_insns (GET_CODE (seq) == SEQUENCE ? seq : head);
6188 #ifdef HAVE_epilogue
6191 rtx insn = get_last_insn ();
6192 rtx prev = prev_nonnote_insn (insn);
6194 /* If we end with a BARRIER, we don't need an epilogue. */
6195 if (! (prev && GET_CODE (prev) == BARRIER))
6201 /* The last basic block ends with a NOTE_INSN_EPILOGUE_BEG, the
6202 epilogue insns, the USE insns at the end of a function,
6203 the jump insn that returns, and then a BARRIER. */
6205 /* Move the USE insns at the end of a function onto a list. */
6207 && GET_CODE (prev) == INSN
6208 && GET_CODE (PATTERN (prev)) == USE)
6211 prev = prev_nonnote_insn (prev);
6213 NEXT_INSN (PREV_INSN (tem)) = NEXT_INSN (tem);
6214 PREV_INSN (NEXT_INSN (tem)) = PREV_INSN (tem);
6217 NEXT_INSN (tem) = first_use;
6218 PREV_INSN (first_use) = tem;
6225 emit_barrier_after (insn);
6227 seq = gen_epilogue ();
6228 tail = emit_jump_insn_after (seq, insn);
6230 /* Insert the USE insns immediately before the return insn, which
6231 must be the first instruction before the final barrier. */
6234 tem = prev_nonnote_insn (get_last_insn ());
6235 NEXT_INSN (PREV_INSN (tem)) = first_use;
6236 PREV_INSN (first_use) = PREV_INSN (tem);
6237 PREV_INSN (tem) = last_use;
6238 NEXT_INSN (last_use) = tem;
6241 emit_note_after (NOTE_INSN_EPILOGUE_BEG, insn);
6243 /* Include the new epilogue insns in the last block. Ignore
6244 them if they form a basic block unto themselves. */
6245 if (basic_block_end && n_basic_blocks
6246 && GET_CODE (basic_block_end[n_basic_blocks - 1]) != JUMP_INSN)
6247 basic_block_end[n_basic_blocks - 1] = tail;
6249 /* Retain a map of the epilogue insns. */
6250 epilogue = record_insns (GET_CODE (seq) == SEQUENCE ? seq : tail);
6258 /* Reposition the prologue-end and epilogue-begin notes after instruction
6259 scheduling and delayed branch scheduling. */
6262 reposition_prologue_and_epilogue_notes (f)
6265 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
6266 /* Reposition the prologue and epilogue notes. */
6274 register rtx insn, note = 0;
6276 /* Scan from the beginning until we reach the last prologue insn.
6277 We apparently can't depend on basic_block_{head,end} after
6279 for (len = 0; prologue[len]; len++)
6281 for (insn = f; len && insn; insn = NEXT_INSN (insn))
6283 if (GET_CODE (insn) == NOTE)
6285 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
6288 else if ((len -= contains (insn, prologue)) == 0)
6290 /* Find the prologue-end note if we haven't already, and
6291 move it to just after the last prologue insn. */
6294 for (note = insn; (note = NEXT_INSN (note));)
6295 if (GET_CODE (note) == NOTE
6296 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
6300 next = NEXT_INSN (note);
6301 prev = PREV_INSN (note);
6303 NEXT_INSN (prev) = next;
6305 PREV_INSN (next) = prev;
6307 /* Whether or not we can depend on basic_block_head,
6308 attempt to keep it up-to-date. */
6309 if (basic_block_head[0] == note)
6310 basic_block_head[0] = next;
6312 add_insn_after (note, insn);
6319 register rtx insn, note = 0;
6321 /* Scan from the end until we reach the first epilogue insn.
6322 We apparently can't depend on basic_block_{head,end} after
6324 for (len = 0; epilogue[len]; len++)
6326 for (insn = get_last_insn (); len && insn; insn = PREV_INSN (insn))
6328 if (GET_CODE (insn) == NOTE)
6330 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
6333 else if ((len -= contains (insn, epilogue)) == 0)
6335 /* Find the epilogue-begin note if we haven't already, and
6336 move it to just before the first epilogue insn. */
6339 for (note = insn; (note = PREV_INSN (note));)
6340 if (GET_CODE (note) == NOTE
6341 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
6344 next = NEXT_INSN (note);
6345 prev = PREV_INSN (note);
6347 NEXT_INSN (prev) = next;
6349 PREV_INSN (next) = prev;
6351 /* Whether or not we can depend on basic_block_head,
6352 attempt to keep it up-to-date. */
6354 && basic_block_head[n_basic_blocks-1] == insn)
6355 basic_block_head[n_basic_blocks-1] = note;
6357 add_insn_before (note, insn);
6362 #endif /* HAVE_prologue or HAVE_epilogue */