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"
59 #ifndef TRAMPOLINE_ALIGNMENT
60 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
63 /* Some systems use __main in a way incompatible with its use in gcc, in these
64 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
65 give the same symbol without quotes for an alternative entry point. You
66 must define both, or neither. */
68 #define NAME__MAIN "__main"
69 #define SYMBOL__MAIN __main
72 /* Round a value to the lowest integer less than it that is a multiple of
73 the required alignment. Avoid using division in case the value is
74 negative. Assume the alignment is a power of two. */
75 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
77 /* Similar, but round to the next highest integer that meets the
79 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
81 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
82 during rtl generation. If they are different register numbers, this is
83 always true. It may also be true if
84 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
85 generation. See fix_lexical_addr for details. */
87 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
88 #define NEED_SEPARATE_AP
91 /* Number of bytes of args popped by function being compiled on its return.
92 Zero if no bytes are to be popped.
93 May affect compilation of return insn or of function epilogue. */
95 int current_function_pops_args;
97 /* Nonzero if function being compiled needs to be given an address
98 where the value should be stored. */
100 int current_function_returns_struct;
102 /* Nonzero if function being compiled needs to
103 return the address of where it has put a structure value. */
105 int current_function_returns_pcc_struct;
107 /* Nonzero if function being compiled needs to be passed a static chain. */
109 int current_function_needs_context;
111 /* Nonzero if function being compiled can call setjmp. */
113 int current_function_calls_setjmp;
115 /* Nonzero if function being compiled can call longjmp. */
117 int current_function_calls_longjmp;
119 /* Nonzero if function being compiled receives nonlocal gotos
120 from nested functions. */
122 int current_function_has_nonlocal_label;
124 /* Nonzero if function being compiled has nonlocal gotos to parent
127 int current_function_has_nonlocal_goto;
129 /* Nonzero if this function has a computed goto.
131 It is computed during find_basic_blocks or during stupid life
134 int current_function_has_computed_jump;
136 /* Nonzero if function being compiled contains nested functions. */
138 int current_function_contains_functions;
140 /* Nonzero if the current function is a thunk (a lightweight function that
141 just adjusts one of its arguments and forwards to another function), so
142 we should try to cut corners where we can. */
143 int current_function_is_thunk;
145 /* Nonzero if function being compiled can call alloca,
146 either as a subroutine or builtin. */
148 int current_function_calls_alloca;
150 /* Nonzero if the current function returns a pointer type */
152 int current_function_returns_pointer;
154 /* If some insns can be deferred to the delay slots of the epilogue, the
155 delay list for them is recorded here. */
157 rtx current_function_epilogue_delay_list;
159 /* If function's args have a fixed size, this is that size, in bytes.
161 May affect compilation of return insn or of function epilogue. */
163 int current_function_args_size;
165 /* # bytes the prologue should push and pretend that the caller pushed them.
166 The prologue must do this, but only if parms can be passed in registers. */
168 int current_function_pretend_args_size;
170 /* # of bytes of outgoing arguments. If ACCUMULATE_OUTGOING_ARGS is
171 defined, the needed space is pushed by the prologue. */
173 int current_function_outgoing_args_size;
175 /* This is the offset from the arg pointer to the place where the first
176 anonymous arg can be found, if there is one. */
178 rtx current_function_arg_offset_rtx;
180 /* Nonzero if current function uses varargs.h or equivalent.
181 Zero for functions that use stdarg.h. */
183 int current_function_varargs;
185 /* Nonzero if current function uses stdarg.h or equivalent.
186 Zero for functions that use varargs.h. */
188 int current_function_stdarg;
190 /* Quantities of various kinds of registers
191 used for the current function's args. */
193 CUMULATIVE_ARGS current_function_args_info;
195 /* Name of function now being compiled. */
197 char *current_function_name;
199 /* If non-zero, an RTL expression for the location at which the current
200 function returns its result. If the current function returns its
201 result in a register, current_function_return_rtx will always be
202 the hard register containing the result. */
204 rtx current_function_return_rtx;
206 /* Nonzero if the current function uses the constant pool. */
208 int current_function_uses_const_pool;
210 /* Nonzero if the current function uses pic_offset_table_rtx. */
211 int current_function_uses_pic_offset_table;
213 /* The arg pointer hard register, or the pseudo into which it was copied. */
214 rtx current_function_internal_arg_pointer;
216 /* The FUNCTION_DECL for an inline function currently being expanded. */
217 tree inline_function_decl;
219 /* Number of function calls seen so far in current function. */
221 int function_call_count;
223 /* List (chain of TREE_LIST) of LABEL_DECLs for all nonlocal labels
224 (labels to which there can be nonlocal gotos from nested functions)
227 tree nonlocal_labels;
229 /* RTX for stack slot that holds the current handler for nonlocal gotos.
230 Zero when function does not have nonlocal labels. */
232 rtx nonlocal_goto_handler_slot;
234 /* RTX for stack slot that holds the stack pointer value to restore
236 Zero when function does not have nonlocal labels. */
238 rtx nonlocal_goto_stack_level;
240 /* Label that will go on parm cleanup code, if any.
241 Jumping to this label runs cleanup code for parameters, if
242 such code must be run. Following this code is the logical return label. */
246 /* Label that will go on function epilogue.
247 Jumping to this label serves as a "return" instruction
248 on machines which require execution of the epilogue on all returns. */
252 /* List (chain of EXPR_LISTs) of pseudo-regs of SAVE_EXPRs.
253 So we can mark them all live at the end of the function, if nonopt. */
256 /* List (chain of EXPR_LISTs) of all stack slots in this function.
257 Made for the sake of unshare_all_rtl. */
260 /* Chain of all RTL_EXPRs that have insns in them. */
263 /* Label to jump back to for tail recursion, or 0 if we have
264 not yet needed one for this function. */
265 rtx tail_recursion_label;
267 /* Place after which to insert the tail_recursion_label if we need one. */
268 rtx tail_recursion_reentry;
270 /* Location at which to save the argument pointer if it will need to be
271 referenced. There are two cases where this is done: if nonlocal gotos
272 exist, or if vars stored at an offset from the argument pointer will be
273 needed by inner routines. */
275 rtx arg_pointer_save_area;
277 /* Offset to end of allocated area of stack frame.
278 If stack grows down, this is the address of the last stack slot allocated.
279 If stack grows up, this is the address for the next slot. */
280 HOST_WIDE_INT frame_offset;
282 /* List (chain of TREE_LISTs) of static chains for containing functions.
283 Each link has a FUNCTION_DECL in the TREE_PURPOSE and a reg rtx
284 in an RTL_EXPR in the TREE_VALUE. */
285 static tree context_display;
287 /* List (chain of TREE_LISTs) of trampolines for nested functions.
288 The trampoline sets up the static chain and jumps to the function.
289 We supply the trampoline's address when the function's address is requested.
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 trampoline_list;
295 /* Insn after which register parms and SAVE_EXPRs are born, if nonopt. */
296 static rtx parm_birth_insn;
299 /* Nonzero if a stack slot has been generated whose address is not
300 actually valid. It means that the generated rtl must all be scanned
301 to detect and correct the invalid addresses where they occur. */
302 static int invalid_stack_slot;
305 /* Last insn of those whose job was to put parms into their nominal homes. */
306 static rtx last_parm_insn;
308 /* 1 + last pseudo register number possibly used for loading a copy
309 of a parameter of this function. */
312 /* Vector indexed by REGNO, containing location on stack in which
313 to put the parm which is nominally in pseudo register REGNO,
314 if we discover that that parm must go in the stack. The highest
315 element in this vector is one less than MAX_PARM_REG, above. */
316 rtx *parm_reg_stack_loc;
318 /* Nonzero once virtual register instantiation has been done.
319 assign_stack_local uses frame_pointer_rtx when this is nonzero. */
320 static int virtuals_instantiated;
322 /* These variables hold pointers to functions to
323 save and restore machine-specific data,
324 in push_function_context and pop_function_context. */
325 void (*save_machine_status) PROTO((struct function *));
326 void (*restore_machine_status) PROTO((struct function *));
328 /* Nonzero if we need to distinguish between the return value of this function
329 and the return value of a function called by this function. This helps
332 extern int rtx_equal_function_value_matters;
333 extern tree sequence_rtl_expr;
335 /* In order to evaluate some expressions, such as function calls returning
336 structures in memory, we need to temporarily allocate stack locations.
337 We record each allocated temporary in the following structure.
339 Associated with each temporary slot is a nesting level. When we pop up
340 one level, all temporaries associated with the previous level are freed.
341 Normally, all temporaries are freed after the execution of the statement
342 in which they were created. However, if we are inside a ({...}) grouping,
343 the result may be in a temporary and hence must be preserved. If the
344 result could be in a temporary, we preserve it if we can determine which
345 one it is in. If we cannot determine which temporary may contain the
346 result, all temporaries are preserved. A temporary is preserved by
347 pretending it was allocated at the previous nesting level.
349 Automatic variables are also assigned temporary slots, at the nesting
350 level where they are defined. They are marked a "kept" so that
351 free_temp_slots will not free them. */
355 /* Points to next temporary slot. */
356 struct temp_slot *next;
357 /* The rtx to used to reference the slot. */
359 /* The rtx used to represent the address if not the address of the
360 slot above. May be an EXPR_LIST if multiple addresses exist. */
362 /* The size, in units, of the slot. */
364 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
366 /* Non-zero if this temporary is currently in use. */
368 /* Non-zero if this temporary has its address taken. */
370 /* Nesting level at which this slot is being used. */
372 /* Non-zero if this should survive a call to free_temp_slots. */
374 /* The offset of the slot from the frame_pointer, including extra space
375 for alignment. This info is for combine_temp_slots. */
376 HOST_WIDE_INT base_offset;
377 /* The size of the slot, including extra space for alignment. This
378 info is for combine_temp_slots. */
379 HOST_WIDE_INT full_size;
382 /* List of all temporaries allocated, both available and in use. */
384 struct temp_slot *temp_slots;
386 /* Current nesting level for temporaries. */
390 /* Current nesting level for variables in a block. */
392 int var_temp_slot_level;
394 /* This structure is used to record MEMs or pseudos used to replace VAR, any
395 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
396 maintain this list in case two operands of an insn were required to match;
397 in that case we must ensure we use the same replacement. */
399 struct fixup_replacement
403 struct fixup_replacement *next;
406 /* Forward declarations. */
408 static rtx assign_outer_stack_local PROTO ((enum machine_mode, HOST_WIDE_INT,
409 int, struct function *));
410 static struct temp_slot *find_temp_slot_from_address PROTO((rtx));
411 static void put_reg_into_stack PROTO((struct function *, rtx, tree,
412 enum machine_mode, enum machine_mode,
414 static void fixup_var_refs PROTO((rtx, enum machine_mode, int));
415 static struct fixup_replacement
416 *find_fixup_replacement PROTO((struct fixup_replacement **, rtx));
417 static void fixup_var_refs_insns PROTO((rtx, enum machine_mode, int,
419 static void fixup_var_refs_1 PROTO((rtx, enum machine_mode, rtx *, rtx,
420 struct fixup_replacement **));
421 static rtx fixup_memory_subreg PROTO((rtx, rtx, int));
422 static rtx walk_fixup_memory_subreg PROTO((rtx, rtx, int));
423 static rtx fixup_stack_1 PROTO((rtx, rtx));
424 static void optimize_bit_field PROTO((rtx, rtx, rtx *));
425 static void instantiate_decls PROTO((tree, int));
426 static void instantiate_decls_1 PROTO((tree, int));
427 static void instantiate_decl PROTO((rtx, int, int));
428 static int instantiate_virtual_regs_1 PROTO((rtx *, rtx, int));
429 static void delete_handlers PROTO((void));
430 static void pad_to_arg_alignment PROTO((struct args_size *, int));
431 #ifndef ARGS_GROW_DOWNWARD
432 static void pad_below PROTO((struct args_size *, enum machine_mode,
435 static tree round_down PROTO((tree, int));
436 static rtx round_trampoline_addr PROTO((rtx));
437 static tree blocks_nreverse PROTO((tree));
438 static int all_blocks PROTO((tree, tree *));
439 static int *record_insns PROTO((rtx));
440 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
441 static int contains PROTO((rtx, int *));
442 #endif /* HAVE_prologue || HAVE_epilogue */
443 static void put_addressof_into_stack PROTO((rtx));
444 static void purge_addressof_1 PROTO((rtx *, rtx, int));
446 /* Pointer to chain of `struct function' for containing functions. */
447 struct function *outer_function_chain;
449 /* Given a function decl for a containing function,
450 return the `struct function' for it. */
453 find_function_data (decl)
458 for (p = outer_function_chain; p; p = p->next)
465 /* Save the current context for compilation of a nested function.
466 This is called from language-specific code.
467 The caller is responsible for saving any language-specific status,
468 since this function knows only about language-independent variables. */
471 push_function_context_to (context)
474 struct function *p = (struct function *) xmalloc (sizeof (struct function));
476 p->next = outer_function_chain;
477 outer_function_chain = p;
479 p->name = current_function_name;
480 p->decl = current_function_decl;
481 p->pops_args = current_function_pops_args;
482 p->returns_struct = current_function_returns_struct;
483 p->returns_pcc_struct = current_function_returns_pcc_struct;
484 p->returns_pointer = current_function_returns_pointer;
485 p->needs_context = current_function_needs_context;
486 p->calls_setjmp = current_function_calls_setjmp;
487 p->calls_longjmp = current_function_calls_longjmp;
488 p->calls_alloca = current_function_calls_alloca;
489 p->has_nonlocal_label = current_function_has_nonlocal_label;
490 p->has_nonlocal_goto = current_function_has_nonlocal_goto;
491 p->contains_functions = current_function_contains_functions;
492 p->is_thunk = current_function_is_thunk;
493 p->args_size = current_function_args_size;
494 p->pretend_args_size = current_function_pretend_args_size;
495 p->arg_offset_rtx = current_function_arg_offset_rtx;
496 p->varargs = current_function_varargs;
497 p->stdarg = current_function_stdarg;
498 p->uses_const_pool = current_function_uses_const_pool;
499 p->uses_pic_offset_table = current_function_uses_pic_offset_table;
500 p->internal_arg_pointer = current_function_internal_arg_pointer;
501 p->max_parm_reg = max_parm_reg;
502 p->parm_reg_stack_loc = parm_reg_stack_loc;
503 p->outgoing_args_size = current_function_outgoing_args_size;
504 p->return_rtx = current_function_return_rtx;
505 p->nonlocal_goto_handler_slot = nonlocal_goto_handler_slot;
506 p->nonlocal_goto_stack_level = nonlocal_goto_stack_level;
507 p->nonlocal_labels = nonlocal_labels;
508 p->cleanup_label = cleanup_label;
509 p->return_label = return_label;
510 p->save_expr_regs = save_expr_regs;
511 p->stack_slot_list = stack_slot_list;
512 p->parm_birth_insn = parm_birth_insn;
513 p->frame_offset = frame_offset;
514 p->tail_recursion_label = tail_recursion_label;
515 p->tail_recursion_reentry = tail_recursion_reentry;
516 p->arg_pointer_save_area = arg_pointer_save_area;
517 p->rtl_expr_chain = rtl_expr_chain;
518 p->last_parm_insn = last_parm_insn;
519 p->context_display = context_display;
520 p->trampoline_list = trampoline_list;
521 p->function_call_count = function_call_count;
522 p->temp_slots = temp_slots;
523 p->temp_slot_level = temp_slot_level;
524 p->target_temp_slot_level = target_temp_slot_level;
525 p->var_temp_slot_level = var_temp_slot_level;
526 p->fixup_var_refs_queue = 0;
527 p->epilogue_delay_list = current_function_epilogue_delay_list;
528 p->args_info = current_function_args_info;
530 save_tree_status (p, context);
531 save_storage_status (p);
532 save_emit_status (p);
533 save_expr_status (p);
534 save_stmt_status (p);
535 save_varasm_status (p, context);
536 if (save_machine_status)
537 (*save_machine_status) (p);
541 push_function_context ()
543 push_function_context_to (current_function_decl);
546 /* Restore the last saved context, at the end of a nested function.
547 This function is called from language-specific code. */
550 pop_function_context_from (context)
553 struct function *p = outer_function_chain;
554 struct var_refs_queue *queue;
556 outer_function_chain = p->next;
558 current_function_contains_functions
559 = p->contains_functions || p->inline_obstacks
560 || context == current_function_decl;
561 current_function_name = p->name;
562 current_function_decl = p->decl;
563 current_function_pops_args = p->pops_args;
564 current_function_returns_struct = p->returns_struct;
565 current_function_returns_pcc_struct = p->returns_pcc_struct;
566 current_function_returns_pointer = p->returns_pointer;
567 current_function_needs_context = p->needs_context;
568 current_function_calls_setjmp = p->calls_setjmp;
569 current_function_calls_longjmp = p->calls_longjmp;
570 current_function_calls_alloca = p->calls_alloca;
571 current_function_has_nonlocal_label = p->has_nonlocal_label;
572 current_function_has_nonlocal_goto = p->has_nonlocal_goto;
573 current_function_is_thunk = p->is_thunk;
574 current_function_args_size = p->args_size;
575 current_function_pretend_args_size = p->pretend_args_size;
576 current_function_arg_offset_rtx = p->arg_offset_rtx;
577 current_function_varargs = p->varargs;
578 current_function_stdarg = p->stdarg;
579 current_function_uses_const_pool = p->uses_const_pool;
580 current_function_uses_pic_offset_table = p->uses_pic_offset_table;
581 current_function_internal_arg_pointer = p->internal_arg_pointer;
582 max_parm_reg = p->max_parm_reg;
583 parm_reg_stack_loc = p->parm_reg_stack_loc;
584 current_function_outgoing_args_size = p->outgoing_args_size;
585 current_function_return_rtx = p->return_rtx;
586 nonlocal_goto_handler_slot = p->nonlocal_goto_handler_slot;
587 nonlocal_goto_stack_level = p->nonlocal_goto_stack_level;
588 nonlocal_labels = p->nonlocal_labels;
589 cleanup_label = p->cleanup_label;
590 return_label = p->return_label;
591 save_expr_regs = p->save_expr_regs;
592 stack_slot_list = p->stack_slot_list;
593 parm_birth_insn = p->parm_birth_insn;
594 frame_offset = p->frame_offset;
595 tail_recursion_label = p->tail_recursion_label;
596 tail_recursion_reentry = p->tail_recursion_reentry;
597 arg_pointer_save_area = p->arg_pointer_save_area;
598 rtl_expr_chain = p->rtl_expr_chain;
599 last_parm_insn = p->last_parm_insn;
600 context_display = p->context_display;
601 trampoline_list = p->trampoline_list;
602 function_call_count = p->function_call_count;
603 temp_slots = p->temp_slots;
604 temp_slot_level = p->temp_slot_level;
605 target_temp_slot_level = p->target_temp_slot_level;
606 var_temp_slot_level = p->var_temp_slot_level;
607 current_function_epilogue_delay_list = p->epilogue_delay_list;
609 current_function_args_info = p->args_info;
611 restore_tree_status (p, context);
612 restore_storage_status (p);
613 restore_expr_status (p);
614 restore_emit_status (p);
615 restore_stmt_status (p);
616 restore_varasm_status (p);
618 if (restore_machine_status)
619 (*restore_machine_status) (p);
621 /* Finish doing put_var_into_stack for any of our variables
622 which became addressable during the nested function. */
623 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
624 fixup_var_refs (queue->modified, queue->promoted_mode, queue->unsignedp);
628 /* Reset variables that have known state during rtx generation. */
629 rtx_equal_function_value_matters = 1;
630 virtuals_instantiated = 0;
633 void pop_function_context ()
635 pop_function_context_from (current_function_decl);
638 /* Allocate fixed slots in the stack frame of the current function. */
640 /* Return size needed for stack frame based on slots so far allocated.
641 This size counts from zero. It is not rounded to STACK_BOUNDARY;
642 the caller may have to do that. */
647 #ifdef FRAME_GROWS_DOWNWARD
648 return -frame_offset;
654 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
655 with machine mode MODE.
657 ALIGN controls the amount of alignment for the address of the slot:
658 0 means according to MODE,
659 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
660 positive specifies alignment boundary in bits.
662 We do not round to stack_boundary here. */
665 assign_stack_local (mode, size, align)
666 enum machine_mode mode;
670 register rtx x, addr;
671 int bigend_correction = 0;
676 alignment = GET_MODE_ALIGNMENT (mode) / BITS_PER_UNIT;
678 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
680 else if (align == -1)
682 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
683 size = CEIL_ROUND (size, alignment);
686 alignment = align / BITS_PER_UNIT;
688 /* Round frame offset to that alignment.
689 We must be careful here, since FRAME_OFFSET might be negative and
690 division with a negative dividend isn't as well defined as we might
691 like. So we instead assume that ALIGNMENT is a power of two and
692 use logical operations which are unambiguous. */
693 #ifdef FRAME_GROWS_DOWNWARD
694 frame_offset = FLOOR_ROUND (frame_offset, alignment);
696 frame_offset = CEIL_ROUND (frame_offset, alignment);
699 /* On a big-endian machine, if we are allocating more space than we will use,
700 use the least significant bytes of those that are allocated. */
701 if (BYTES_BIG_ENDIAN && mode != BLKmode)
702 bigend_correction = size - GET_MODE_SIZE (mode);
704 #ifdef FRAME_GROWS_DOWNWARD
705 frame_offset -= size;
708 /* If we have already instantiated virtual registers, return the actual
709 address relative to the frame pointer. */
710 if (virtuals_instantiated)
711 addr = plus_constant (frame_pointer_rtx,
712 (frame_offset + bigend_correction
713 + STARTING_FRAME_OFFSET));
715 addr = plus_constant (virtual_stack_vars_rtx,
716 frame_offset + bigend_correction);
718 #ifndef FRAME_GROWS_DOWNWARD
719 frame_offset += size;
722 x = gen_rtx_MEM (mode, addr);
724 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, x, stack_slot_list);
729 /* Assign a stack slot in a containing function.
730 First three arguments are same as in preceding function.
731 The last argument specifies the function to allocate in. */
734 assign_outer_stack_local (mode, size, align, function)
735 enum machine_mode mode;
738 struct function *function;
740 register rtx x, addr;
741 int bigend_correction = 0;
744 /* Allocate in the memory associated with the function in whose frame
746 push_obstacks (function->function_obstack,
747 function->function_maybepermanent_obstack);
751 alignment = GET_MODE_ALIGNMENT (mode) / BITS_PER_UNIT;
753 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
755 else if (align == -1)
757 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
758 size = CEIL_ROUND (size, alignment);
761 alignment = align / BITS_PER_UNIT;
763 /* Round frame offset to that alignment. */
764 #ifdef FRAME_GROWS_DOWNWARD
765 function->frame_offset = FLOOR_ROUND (function->frame_offset, alignment);
767 function->frame_offset = CEIL_ROUND (function->frame_offset, alignment);
770 /* On a big-endian machine, if we are allocating more space than we will use,
771 use the least significant bytes of those that are allocated. */
772 if (BYTES_BIG_ENDIAN && mode != BLKmode)
773 bigend_correction = size - GET_MODE_SIZE (mode);
775 #ifdef FRAME_GROWS_DOWNWARD
776 function->frame_offset -= size;
778 addr = plus_constant (virtual_stack_vars_rtx,
779 function->frame_offset + bigend_correction);
780 #ifndef FRAME_GROWS_DOWNWARD
781 function->frame_offset += size;
784 x = gen_rtx_MEM (mode, addr);
786 function->stack_slot_list
787 = gen_rtx_EXPR_LIST (VOIDmode, x, function->stack_slot_list);
794 /* Allocate a temporary stack slot and record it for possible later
797 MODE is the machine mode to be given to the returned rtx.
799 SIZE is the size in units of the space required. We do no rounding here
800 since assign_stack_local will do any required rounding.
802 KEEP is 1 if this slot is to be retained after a call to
803 free_temp_slots. Automatic variables for a block are allocated
804 with this flag. KEEP is 2 if we allocate a longer term temporary,
805 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
806 if we are to allocate something at an inner level to be treated as
807 a variable in the block (e.g., a SAVE_EXPR). */
810 assign_stack_temp (mode, size, keep)
811 enum machine_mode mode;
815 struct temp_slot *p, *best_p = 0;
817 /* If SIZE is -1 it means that somebody tried to allocate a temporary
818 of a variable size. */
822 /* First try to find an available, already-allocated temporary that is the
823 exact size we require. */
824 for (p = temp_slots; p; p = p->next)
825 if (p->size == size && GET_MODE (p->slot) == mode && ! p->in_use)
828 /* If we didn't find, one, try one that is larger than what we want. We
829 find the smallest such. */
831 for (p = temp_slots; p; p = p->next)
832 if (p->size > size && GET_MODE (p->slot) == mode && ! p->in_use
833 && (best_p == 0 || best_p->size > p->size))
836 /* Make our best, if any, the one to use. */
839 /* If there are enough aligned bytes left over, make them into a new
840 temp_slot so that the extra bytes don't get wasted. Do this only
841 for BLKmode slots, so that we can be sure of the alignment. */
842 if (GET_MODE (best_p->slot) == BLKmode)
844 int alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
845 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
847 if (best_p->size - rounded_size >= alignment)
849 p = (struct temp_slot *) oballoc (sizeof (struct temp_slot));
850 p->in_use = p->addr_taken = 0;
851 p->size = best_p->size - rounded_size;
852 p->base_offset = best_p->base_offset + rounded_size;
853 p->full_size = best_p->full_size - rounded_size;
854 p->slot = gen_rtx_MEM (BLKmode,
855 plus_constant (XEXP (best_p->slot, 0),
859 p->next = temp_slots;
862 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
865 best_p->size = rounded_size;
866 best_p->full_size = rounded_size;
873 /* If we still didn't find one, make a new temporary. */
876 HOST_WIDE_INT frame_offset_old = frame_offset;
878 p = (struct temp_slot *) oballoc (sizeof (struct temp_slot));
880 /* If the temp slot mode doesn't indicate the alignment,
881 use the largest possible, so no one will be disappointed. */
882 p->slot = assign_stack_local (mode, size, mode == BLKmode ? -1 : 0);
884 /* The following slot size computation is necessary because we don't
885 know the actual size of the temporary slot until assign_stack_local
886 has performed all the frame alignment and size rounding for the
887 requested temporary. Note that extra space added for alignment
888 can be either above or below this stack slot depending on which
889 way the frame grows. We include the extra space if and only if it
890 is above this slot. */
891 #ifdef FRAME_GROWS_DOWNWARD
892 p->size = frame_offset_old - frame_offset;
897 /* Now define the fields used by combine_temp_slots. */
898 #ifdef FRAME_GROWS_DOWNWARD
899 p->base_offset = frame_offset;
900 p->full_size = frame_offset_old - frame_offset;
902 p->base_offset = frame_offset_old;
903 p->full_size = frame_offset - frame_offset_old;
906 p->next = temp_slots;
912 p->rtl_expr = sequence_rtl_expr;
916 p->level = target_temp_slot_level;
921 p->level = var_temp_slot_level;
926 p->level = temp_slot_level;
930 /* We may be reusing an old slot, so clear any MEM flags that may have been
932 RTX_UNCHANGING_P (p->slot) = 0;
933 MEM_IN_STRUCT_P (p->slot) = 0;
937 /* Assign a temporary of given TYPE.
938 KEEP is as for assign_stack_temp.
939 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
940 it is 0 if a register is OK.
941 DONT_PROMOTE is 1 if we should not promote values in register
945 assign_temp (type, keep, memory_required, dont_promote)
951 enum machine_mode mode = TYPE_MODE (type);
952 int unsignedp = TREE_UNSIGNED (type);
954 if (mode == BLKmode || memory_required)
956 HOST_WIDE_INT size = int_size_in_bytes (type);
959 /* Unfortunately, we don't yet know how to allocate variable-sized
960 temporaries. However, sometimes we have a fixed upper limit on
961 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
962 instead. This is the case for Chill variable-sized strings. */
963 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
964 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
965 && TREE_CODE (TYPE_ARRAY_MAX_SIZE (type)) == INTEGER_CST)
966 size = TREE_INT_CST_LOW (TYPE_ARRAY_MAX_SIZE (type));
968 tmp = assign_stack_temp (mode, size, keep);
969 MEM_IN_STRUCT_P (tmp) = AGGREGATE_TYPE_P (type);
973 #ifndef PROMOTE_FOR_CALL_ONLY
975 mode = promote_mode (type, mode, &unsignedp, 0);
978 return gen_reg_rtx (mode);
981 /* Combine temporary stack slots which are adjacent on the stack.
983 This allows for better use of already allocated stack space. This is only
984 done for BLKmode slots because we can be sure that we won't have alignment
985 problems in this case. */
988 combine_temp_slots ()
990 struct temp_slot *p, *q;
991 struct temp_slot *prev_p, *prev_q;
994 /* If there are a lot of temp slots, don't do anything unless
995 high levels of optimizaton. */
996 if (! flag_expensive_optimizations)
997 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
998 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
1001 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
1005 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
1006 for (q = p->next, prev_q = p; q; q = prev_q->next)
1009 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
1011 if (p->base_offset + p->full_size == q->base_offset)
1013 /* Q comes after P; combine Q into P. */
1015 p->full_size += q->full_size;
1018 else if (q->base_offset + q->full_size == p->base_offset)
1020 /* P comes after Q; combine P into Q. */
1022 q->full_size += p->full_size;
1027 /* Either delete Q or advance past it. */
1029 prev_q->next = q->next;
1033 /* Either delete P or advance past it. */
1037 prev_p->next = p->next;
1039 temp_slots = p->next;
1046 /* Find the temp slot corresponding to the object at address X. */
1048 static struct temp_slot *
1049 find_temp_slot_from_address (x)
1052 struct temp_slot *p;
1055 for (p = temp_slots; p; p = p->next)
1060 else if (XEXP (p->slot, 0) == x
1062 || (GET_CODE (x) == PLUS
1063 && XEXP (x, 0) == virtual_stack_vars_rtx
1064 && GET_CODE (XEXP (x, 1)) == CONST_INT
1065 && INTVAL (XEXP (x, 1)) >= p->base_offset
1066 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
1069 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
1070 for (next = p->address; next; next = XEXP (next, 1))
1071 if (XEXP (next, 0) == x)
1078 /* Indicate that NEW is an alternate way of referring to the temp slot
1079 that previously was known by OLD. */
1082 update_temp_slot_address (old, new)
1085 struct temp_slot *p = find_temp_slot_from_address (old);
1087 /* If none, return. Else add NEW as an alias. */
1090 else if (p->address == 0)
1094 if (GET_CODE (p->address) != EXPR_LIST)
1095 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1097 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1101 /* If X could be a reference to a temporary slot, mark the fact that its
1102 address was taken. */
1105 mark_temp_addr_taken (x)
1108 struct temp_slot *p;
1113 /* If X is not in memory or is at a constant address, it cannot be in
1114 a temporary slot. */
1115 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1118 p = find_temp_slot_from_address (XEXP (x, 0));
1123 /* If X could be a reference to a temporary slot, mark that slot as
1124 belonging to the to one level higher than the current level. If X
1125 matched one of our slots, just mark that one. Otherwise, we can't
1126 easily predict which it is, so upgrade all of them. Kept slots
1127 need not be touched.
1129 This is called when an ({...}) construct occurs and a statement
1130 returns a value in memory. */
1133 preserve_temp_slots (x)
1136 struct temp_slot *p = 0;
1138 /* If there is no result, we still might have some objects whose address
1139 were taken, so we need to make sure they stay around. */
1142 for (p = temp_slots; p; p = p->next)
1143 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1149 /* If X is a register that is being used as a pointer, see if we have
1150 a temporary slot we know it points to. To be consistent with
1151 the code below, we really should preserve all non-kept slots
1152 if we can't find a match, but that seems to be much too costly. */
1153 if (GET_CODE (x) == REG && REGNO_POINTER_FLAG (REGNO (x)))
1154 p = find_temp_slot_from_address (x);
1156 /* If X is not in memory or is at a constant address, it cannot be in
1157 a temporary slot, but it can contain something whose address was
1159 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1161 for (p = temp_slots; p; p = p->next)
1162 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1168 /* First see if we can find a match. */
1170 p = find_temp_slot_from_address (XEXP (x, 0));
1174 /* Move everything at our level whose address was taken to our new
1175 level in case we used its address. */
1176 struct temp_slot *q;
1178 if (p->level == temp_slot_level)
1180 for (q = temp_slots; q; q = q->next)
1181 if (q != p && q->addr_taken && q->level == p->level)
1190 /* Otherwise, preserve all non-kept slots at this level. */
1191 for (p = temp_slots; p; p = p->next)
1192 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1196 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1197 with that RTL_EXPR, promote it into a temporary slot at the present
1198 level so it will not be freed when we free slots made in the
1202 preserve_rtl_expr_result (x)
1205 struct temp_slot *p;
1207 /* If X is not in memory or is at a constant address, it cannot be in
1208 a temporary slot. */
1209 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1212 /* If we can find a match, move it to our level unless it is already at
1214 p = find_temp_slot_from_address (XEXP (x, 0));
1217 p->level = MIN (p->level, temp_slot_level);
1224 /* Free all temporaries used so far. This is normally called at the end
1225 of generating code for a statement. Don't free any temporaries
1226 currently in use for an RTL_EXPR that hasn't yet been emitted.
1227 We could eventually do better than this since it can be reused while
1228 generating the same RTL_EXPR, but this is complex and probably not
1234 struct temp_slot *p;
1236 for (p = temp_slots; p; p = p->next)
1237 if (p->in_use && p->level == temp_slot_level && ! p->keep
1238 && p->rtl_expr == 0)
1241 combine_temp_slots ();
1244 /* Free all temporary slots used in T, an RTL_EXPR node. */
1247 free_temps_for_rtl_expr (t)
1250 struct temp_slot *p;
1252 for (p = temp_slots; p; p = p->next)
1253 if (p->rtl_expr == t)
1256 combine_temp_slots ();
1259 /* Mark all temporaries ever allocated in this function as not suitable
1260 for reuse until the current level is exited. */
1263 mark_all_temps_used ()
1265 struct temp_slot *p;
1267 for (p = temp_slots; p; p = p->next)
1269 p->in_use = p->keep = 1;
1270 p->level = MIN (p->level, temp_slot_level);
1274 /* Push deeper into the nesting level for stack temporaries. */
1282 /* Likewise, but save the new level as the place to allocate variables
1286 push_temp_slots_for_block ()
1290 var_temp_slot_level = temp_slot_level;
1293 /* Pop a temporary nesting level. All slots in use in the current level
1299 struct temp_slot *p;
1301 for (p = temp_slots; p; p = p->next)
1302 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1305 combine_temp_slots ();
1310 /* Initialize temporary slots. */
1315 /* We have not allocated any temporaries yet. */
1317 temp_slot_level = 0;
1318 var_temp_slot_level = 0;
1319 target_temp_slot_level = 0;
1322 /* Retroactively move an auto variable from a register to a stack slot.
1323 This is done when an address-reference to the variable is seen. */
1326 put_var_into_stack (decl)
1330 enum machine_mode promoted_mode, decl_mode;
1331 struct function *function = 0;
1333 int can_use_addressof;
1335 context = decl_function_context (decl);
1337 /* Get the current rtl used for this object and it's original mode. */
1338 reg = TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl) : DECL_RTL (decl);
1340 /* No need to do anything if decl has no rtx yet
1341 since in that case caller is setting TREE_ADDRESSABLE
1342 and a stack slot will be assigned when the rtl is made. */
1346 /* Get the declared mode for this object. */
1347 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1348 : DECL_MODE (decl));
1349 /* Get the mode it's actually stored in. */
1350 promoted_mode = GET_MODE (reg);
1352 /* If this variable comes from an outer function,
1353 find that function's saved context. */
1354 if (context != current_function_decl && context != inline_function_decl)
1355 for (function = outer_function_chain; function; function = function->next)
1356 if (function->decl == context)
1359 /* If this is a variable-size object with a pseudo to address it,
1360 put that pseudo into the stack, if the var is nonlocal. */
1361 if (DECL_NONLOCAL (decl)
1362 && GET_CODE (reg) == MEM
1363 && GET_CODE (XEXP (reg, 0)) == REG
1364 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1366 reg = XEXP (reg, 0);
1367 decl_mode = promoted_mode = GET_MODE (reg);
1373 /* FIXME make it work for promoted modes too */
1374 && decl_mode == promoted_mode
1375 #ifdef NON_SAVING_SETJMP
1376 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1380 /* If we can't use ADDRESSOF, make sure we see through one we already
1382 if (! can_use_addressof && GET_CODE (reg) == MEM
1383 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1384 reg = XEXP (XEXP (reg, 0), 0);
1386 /* Now we should have a value that resides in one or more pseudo regs. */
1388 if (GET_CODE (reg) == REG)
1390 /* If this variable lives in the current function and we don't need
1391 to put things in the stack for the sake of setjmp, try to keep it
1392 in a register until we know we actually need the address. */
1393 if (can_use_addressof)
1394 gen_mem_addressof (reg, decl);
1396 put_reg_into_stack (function, reg, TREE_TYPE (decl),
1397 promoted_mode, decl_mode,
1398 TREE_SIDE_EFFECTS (decl), 0,
1400 || DECL_INITIAL (decl) != 0);
1402 else if (GET_CODE (reg) == CONCAT)
1404 /* A CONCAT contains two pseudos; put them both in the stack.
1405 We do it so they end up consecutive. */
1406 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1407 tree part_type = TREE_TYPE (TREE_TYPE (decl));
1408 #ifdef FRAME_GROWS_DOWNWARD
1409 /* Since part 0 should have a lower address, do it second. */
1410 put_reg_into_stack (function, XEXP (reg, 1), part_type, part_mode,
1411 part_mode, TREE_SIDE_EFFECTS (decl), 0,
1412 TREE_USED (decl) || DECL_INITIAL (decl) != 0);
1413 put_reg_into_stack (function, XEXP (reg, 0), part_type, part_mode,
1414 part_mode, TREE_SIDE_EFFECTS (decl), 0,
1415 TREE_USED (decl) || DECL_INITIAL (decl) != 0);
1417 put_reg_into_stack (function, XEXP (reg, 0), part_type, part_mode,
1418 part_mode, TREE_SIDE_EFFECTS (decl), 0,
1419 TREE_USED (decl) || DECL_INITIAL (decl) != 0);
1420 put_reg_into_stack (function, XEXP (reg, 1), part_type, part_mode,
1421 part_mode, TREE_SIDE_EFFECTS (decl), 0,
1422 TREE_USED (decl) || DECL_INITIAL (decl) != 0);
1425 /* Change the CONCAT into a combined MEM for both parts. */
1426 PUT_CODE (reg, MEM);
1427 MEM_VOLATILE_P (reg) = MEM_VOLATILE_P (XEXP (reg, 0));
1429 /* The two parts are in memory order already.
1430 Use the lower parts address as ours. */
1431 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1432 /* Prevent sharing of rtl that might lose. */
1433 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1434 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1439 if (flag_check_memory_usage)
1440 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
1441 XEXP (reg, 0), ptr_mode,
1442 GEN_INT (GET_MODE_SIZE (GET_MODE (reg))),
1443 TYPE_MODE (sizetype),
1444 GEN_INT (MEMORY_USE_RW),
1445 TYPE_MODE (integer_type_node));
1448 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1449 into the stack frame of FUNCTION (0 means the current function).
1450 DECL_MODE is the machine mode of the user-level data type.
1451 PROMOTED_MODE is the machine mode of the register.
1452 VOLATILE_P is nonzero if this is for a "volatile" decl.
1453 USED_P is nonzero if this reg might have already been used in an insn. */
1456 put_reg_into_stack (function, reg, type, promoted_mode, decl_mode, volatile_p,
1457 original_regno, used_p)
1458 struct function *function;
1461 enum machine_mode promoted_mode, decl_mode;
1467 int regno = original_regno;
1470 regno = REGNO (reg);
1474 if (regno < function->max_parm_reg)
1475 new = function->parm_reg_stack_loc[regno];
1477 new = assign_outer_stack_local (decl_mode, GET_MODE_SIZE (decl_mode),
1482 if (regno < max_parm_reg)
1483 new = parm_reg_stack_loc[regno];
1485 new = assign_stack_local (decl_mode, GET_MODE_SIZE (decl_mode), 0);
1488 PUT_MODE (reg, decl_mode);
1489 XEXP (reg, 0) = XEXP (new, 0);
1490 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1491 MEM_VOLATILE_P (reg) = volatile_p;
1492 PUT_CODE (reg, MEM);
1494 /* If this is a memory ref that contains aggregate components,
1495 mark it as such for cse and loop optimize. If we are reusing a
1496 previously generated stack slot, then we need to copy the bit in
1497 case it was set for other reasons. For instance, it is set for
1498 __builtin_va_alist. */
1499 MEM_IN_STRUCT_P (reg) = AGGREGATE_TYPE_P (type) | MEM_IN_STRUCT_P (new);
1501 /* Now make sure that all refs to the variable, previously made
1502 when it was a register, are fixed up to be valid again. */
1504 if (used_p && function != 0)
1506 struct var_refs_queue *temp;
1508 /* Variable is inherited; fix it up when we get back to its function. */
1509 push_obstacks (function->function_obstack,
1510 function->function_maybepermanent_obstack);
1512 /* See comment in restore_tree_status in tree.c for why this needs to be
1513 on saveable obstack. */
1515 = (struct var_refs_queue *) savealloc (sizeof (struct var_refs_queue));
1516 temp->modified = reg;
1517 temp->promoted_mode = promoted_mode;
1518 temp->unsignedp = TREE_UNSIGNED (type);
1519 temp->next = function->fixup_var_refs_queue;
1520 function->fixup_var_refs_queue = temp;
1524 /* Variable is local; fix it up now. */
1525 fixup_var_refs (reg, promoted_mode, TREE_UNSIGNED (type));
1529 fixup_var_refs (var, promoted_mode, unsignedp)
1531 enum machine_mode promoted_mode;
1535 rtx first_insn = get_insns ();
1536 struct sequence_stack *stack = sequence_stack;
1537 tree rtl_exps = rtl_expr_chain;
1539 /* Must scan all insns for stack-refs that exceed the limit. */
1540 fixup_var_refs_insns (var, promoted_mode, unsignedp, first_insn, stack == 0);
1542 /* Scan all pending sequences too. */
1543 for (; stack; stack = stack->next)
1545 push_to_sequence (stack->first);
1546 fixup_var_refs_insns (var, promoted_mode, unsignedp,
1547 stack->first, stack->next != 0);
1548 /* Update remembered end of sequence
1549 in case we added an insn at the end. */
1550 stack->last = get_last_insn ();
1554 /* Scan all waiting RTL_EXPRs too. */
1555 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1557 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1558 if (seq != const0_rtx && seq != 0)
1560 push_to_sequence (seq);
1561 fixup_var_refs_insns (var, promoted_mode, unsignedp, seq, 0);
1567 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1568 some part of an insn. Return a struct fixup_replacement whose OLD
1569 value is equal to X. Allocate a new structure if no such entry exists. */
1571 static struct fixup_replacement *
1572 find_fixup_replacement (replacements, x)
1573 struct fixup_replacement **replacements;
1576 struct fixup_replacement *p;
1578 /* See if we have already replaced this. */
1579 for (p = *replacements; p && p->old != x; p = p->next)
1584 p = (struct fixup_replacement *) oballoc (sizeof (struct fixup_replacement));
1587 p->next = *replacements;
1594 /* Scan the insn-chain starting with INSN for refs to VAR
1595 and fix them up. TOPLEVEL is nonzero if this chain is the
1596 main chain of insns for the current function. */
1599 fixup_var_refs_insns (var, promoted_mode, unsignedp, insn, toplevel)
1601 enum machine_mode promoted_mode;
1610 rtx next = NEXT_INSN (insn);
1611 rtx set, prev, prev_set;
1614 if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
1616 /* If this is a CLOBBER of VAR, delete it.
1618 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1619 and REG_RETVAL notes too. */
1620 if (GET_CODE (PATTERN (insn)) == CLOBBER
1621 && XEXP (PATTERN (insn), 0) == var)
1623 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1624 /* The REG_LIBCALL note will go away since we are going to
1625 turn INSN into a NOTE, so just delete the
1626 corresponding REG_RETVAL note. */
1627 remove_note (XEXP (note, 0),
1628 find_reg_note (XEXP (note, 0), REG_RETVAL,
1631 /* In unoptimized compilation, we shouldn't call delete_insn
1632 except in jump.c doing warnings. */
1633 PUT_CODE (insn, NOTE);
1634 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1635 NOTE_SOURCE_FILE (insn) = 0;
1638 /* The insn to load VAR from a home in the arglist
1639 is now a no-op. When we see it, just delete it.
1640 Similarly if this is storing VAR from a register from which
1641 it was loaded in the previous insn. This will occur
1642 when an ADDRESSOF was made for an arglist slot. */
1644 && (set = single_set (insn)) != 0
1645 && SET_DEST (set) == var
1646 /* If this represents the result of an insn group,
1647 don't delete the insn. */
1648 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1649 && (rtx_equal_p (SET_SRC (set), var)
1650 || (GET_CODE (SET_SRC (set)) == REG
1651 && (prev = prev_nonnote_insn (insn)) != 0
1652 && (prev_set = single_set (prev)) != 0
1653 && SET_DEST (prev_set) == SET_SRC (set)
1654 && rtx_equal_p (SET_SRC (prev_set), var))))
1656 /* In unoptimized compilation, we shouldn't call delete_insn
1657 except in jump.c doing warnings. */
1658 PUT_CODE (insn, NOTE);
1659 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1660 NOTE_SOURCE_FILE (insn) = 0;
1661 if (insn == last_parm_insn)
1662 last_parm_insn = PREV_INSN (next);
1666 struct fixup_replacement *replacements = 0;
1667 rtx next_insn = NEXT_INSN (insn);
1669 if (SMALL_REGISTER_CLASSES)
1671 /* If the insn that copies the results of a CALL_INSN
1672 into a pseudo now references VAR, we have to use an
1673 intermediate pseudo since we want the life of the
1674 return value register to be only a single insn.
1676 If we don't use an intermediate pseudo, such things as
1677 address computations to make the address of VAR valid
1678 if it is not can be placed between the CALL_INSN and INSN.
1680 To make sure this doesn't happen, we record the destination
1681 of the CALL_INSN and see if the next insn uses both that
1684 if (call_dest != 0 && GET_CODE (insn) == INSN
1685 && reg_mentioned_p (var, PATTERN (insn))
1686 && reg_mentioned_p (call_dest, PATTERN (insn)))
1688 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1690 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1692 PATTERN (insn) = replace_rtx (PATTERN (insn),
1696 if (GET_CODE (insn) == CALL_INSN
1697 && GET_CODE (PATTERN (insn)) == SET)
1698 call_dest = SET_DEST (PATTERN (insn));
1699 else if (GET_CODE (insn) == CALL_INSN
1700 && GET_CODE (PATTERN (insn)) == PARALLEL
1701 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1702 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1707 /* See if we have to do anything to INSN now that VAR is in
1708 memory. If it needs to be loaded into a pseudo, use a single
1709 pseudo for the entire insn in case there is a MATCH_DUP
1710 between two operands. We pass a pointer to the head of
1711 a list of struct fixup_replacements. If fixup_var_refs_1
1712 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1713 it will record them in this list.
1715 If it allocated a pseudo for any replacement, we copy into
1718 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1721 /* If this is last_parm_insn, and any instructions were output
1722 after it to fix it up, then we must set last_parm_insn to
1723 the last such instruction emitted. */
1724 if (insn == last_parm_insn)
1725 last_parm_insn = PREV_INSN (next_insn);
1727 while (replacements)
1729 if (GET_CODE (replacements->new) == REG)
1734 /* OLD might be a (subreg (mem)). */
1735 if (GET_CODE (replacements->old) == SUBREG)
1737 = fixup_memory_subreg (replacements->old, insn, 0);
1740 = fixup_stack_1 (replacements->old, insn);
1742 insert_before = insn;
1744 /* If we are changing the mode, do a conversion.
1745 This might be wasteful, but combine.c will
1746 eliminate much of the waste. */
1748 if (GET_MODE (replacements->new)
1749 != GET_MODE (replacements->old))
1752 convert_move (replacements->new,
1753 replacements->old, unsignedp);
1754 seq = gen_sequence ();
1758 seq = gen_move_insn (replacements->new,
1761 emit_insn_before (seq, insert_before);
1764 replacements = replacements->next;
1768 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1769 But don't touch other insns referred to by reg-notes;
1770 we will get them elsewhere. */
1771 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
1772 if (GET_CODE (note) != INSN_LIST)
1774 = walk_fixup_memory_subreg (XEXP (note, 0), insn, 1);
1780 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1781 See if the rtx expression at *LOC in INSN needs to be changed.
1783 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1784 contain a list of original rtx's and replacements. If we find that we need
1785 to modify this insn by replacing a memory reference with a pseudo or by
1786 making a new MEM to implement a SUBREG, we consult that list to see if
1787 we have already chosen a replacement. If none has already been allocated,
1788 we allocate it and update the list. fixup_var_refs_insns will copy VAR
1789 or the SUBREG, as appropriate, to the pseudo. */
1792 fixup_var_refs_1 (var, promoted_mode, loc, insn, replacements)
1794 enum machine_mode promoted_mode;
1797 struct fixup_replacement **replacements;
1800 register rtx x = *loc;
1801 RTX_CODE code = GET_CODE (x);
1803 register rtx tem, tem1;
1804 struct fixup_replacement *replacement;
1809 if (XEXP (x, 0) == var)
1811 /* Prevent sharing of rtl that might lose. */
1812 rtx sub = copy_rtx (XEXP (var, 0));
1816 if (! validate_change (insn, loc, sub, 0))
1818 rtx y = force_operand (sub, NULL_RTX);
1820 if (! validate_change (insn, loc, y, 0))
1821 *loc = copy_to_reg (y);
1824 emit_insn_before (gen_sequence (), insn);
1832 /* If we already have a replacement, use it. Otherwise,
1833 try to fix up this address in case it is invalid. */
1835 replacement = find_fixup_replacement (replacements, var);
1836 if (replacement->new)
1838 *loc = replacement->new;
1842 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1844 /* Unless we are forcing memory to register or we changed the mode,
1845 we can leave things the way they are if the insn is valid. */
1847 INSN_CODE (insn) = -1;
1848 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1849 && recog_memoized (insn) >= 0)
1852 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1856 /* If X contains VAR, we need to unshare it here so that we update
1857 each occurrence separately. But all identical MEMs in one insn
1858 must be replaced with the same rtx because of the possibility of
1861 if (reg_mentioned_p (var, x))
1863 replacement = find_fixup_replacement (replacements, x);
1864 if (replacement->new == 0)
1865 replacement->new = copy_most_rtx (x, var);
1867 *loc = x = replacement->new;
1883 /* Note that in some cases those types of expressions are altered
1884 by optimize_bit_field, and do not survive to get here. */
1885 if (XEXP (x, 0) == var
1886 || (GET_CODE (XEXP (x, 0)) == SUBREG
1887 && SUBREG_REG (XEXP (x, 0)) == var))
1889 /* Get TEM as a valid MEM in the mode presently in the insn.
1891 We don't worry about the possibility of MATCH_DUP here; it
1892 is highly unlikely and would be tricky to handle. */
1895 if (GET_CODE (tem) == SUBREG)
1897 if (GET_MODE_BITSIZE (GET_MODE (tem))
1898 > GET_MODE_BITSIZE (GET_MODE (var)))
1900 replacement = find_fixup_replacement (replacements, var);
1901 if (replacement->new == 0)
1902 replacement->new = gen_reg_rtx (GET_MODE (var));
1903 SUBREG_REG (tem) = replacement->new;
1906 tem = fixup_memory_subreg (tem, insn, 0);
1909 tem = fixup_stack_1 (tem, insn);
1911 /* Unless we want to load from memory, get TEM into the proper mode
1912 for an extract from memory. This can only be done if the
1913 extract is at a constant position and length. */
1915 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
1916 && GET_CODE (XEXP (x, 2)) == CONST_INT
1917 && ! mode_dependent_address_p (XEXP (tem, 0))
1918 && ! MEM_VOLATILE_P (tem))
1920 enum machine_mode wanted_mode = VOIDmode;
1921 enum machine_mode is_mode = GET_MODE (tem);
1922 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
1925 if (GET_CODE (x) == ZERO_EXTRACT)
1926 wanted_mode = insn_operand_mode[(int) CODE_FOR_extzv][1];
1929 if (GET_CODE (x) == SIGN_EXTRACT)
1930 wanted_mode = insn_operand_mode[(int) CODE_FOR_extv][1];
1932 /* If we have a narrower mode, we can do something. */
1933 if (wanted_mode != VOIDmode
1934 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
1936 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
1937 rtx old_pos = XEXP (x, 2);
1940 /* If the bytes and bits are counted differently, we
1941 must adjust the offset. */
1942 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
1943 offset = (GET_MODE_SIZE (is_mode)
1944 - GET_MODE_SIZE (wanted_mode) - offset);
1946 pos %= GET_MODE_BITSIZE (wanted_mode);
1948 newmem = gen_rtx_MEM (wanted_mode,
1949 plus_constant (XEXP (tem, 0), offset));
1950 RTX_UNCHANGING_P (newmem) = RTX_UNCHANGING_P (tem);
1951 MEM_VOLATILE_P (newmem) = MEM_VOLATILE_P (tem);
1952 MEM_IN_STRUCT_P (newmem) = MEM_IN_STRUCT_P (tem);
1954 /* Make the change and see if the insn remains valid. */
1955 INSN_CODE (insn) = -1;
1956 XEXP (x, 0) = newmem;
1957 XEXP (x, 2) = GEN_INT (pos);
1959 if (recog_memoized (insn) >= 0)
1962 /* Otherwise, restore old position. XEXP (x, 0) will be
1964 XEXP (x, 2) = old_pos;
1968 /* If we get here, the bitfield extract insn can't accept a memory
1969 reference. Copy the input into a register. */
1971 tem1 = gen_reg_rtx (GET_MODE (tem));
1972 emit_insn_before (gen_move_insn (tem1, tem), insn);
1979 if (SUBREG_REG (x) == var)
1981 /* If this is a special SUBREG made because VAR was promoted
1982 from a wider mode, replace it with VAR and call ourself
1983 recursively, this time saying that the object previously
1984 had its current mode (by virtue of the SUBREG). */
1986 if (SUBREG_PROMOTED_VAR_P (x))
1989 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements);
1993 /* If this SUBREG makes VAR wider, it has become a paradoxical
1994 SUBREG with VAR in memory, but these aren't allowed at this
1995 stage of the compilation. So load VAR into a pseudo and take
1996 a SUBREG of that pseudo. */
1997 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
1999 replacement = find_fixup_replacement (replacements, var);
2000 if (replacement->new == 0)
2001 replacement->new = gen_reg_rtx (GET_MODE (var));
2002 SUBREG_REG (x) = replacement->new;
2006 /* See if we have already found a replacement for this SUBREG.
2007 If so, use it. Otherwise, make a MEM and see if the insn
2008 is recognized. If not, or if we should force MEM into a register,
2009 make a pseudo for this SUBREG. */
2010 replacement = find_fixup_replacement (replacements, x);
2011 if (replacement->new)
2013 *loc = replacement->new;
2017 replacement->new = *loc = fixup_memory_subreg (x, insn, 0);
2019 INSN_CODE (insn) = -1;
2020 if (! flag_force_mem && recog_memoized (insn) >= 0)
2023 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2029 /* First do special simplification of bit-field references. */
2030 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2031 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2032 optimize_bit_field (x, insn, 0);
2033 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2034 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2035 optimize_bit_field (x, insn, NULL_PTR);
2037 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2038 into a register and then store it back out. */
2039 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2040 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2041 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2042 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2043 > GET_MODE_SIZE (GET_MODE (var))))
2045 replacement = find_fixup_replacement (replacements, var);
2046 if (replacement->new == 0)
2047 replacement->new = gen_reg_rtx (GET_MODE (var));
2049 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2050 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2053 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2054 insn into a pseudo and store the low part of the pseudo into VAR. */
2055 if (GET_CODE (SET_DEST (x)) == SUBREG
2056 && SUBREG_REG (SET_DEST (x)) == var
2057 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2058 > GET_MODE_SIZE (GET_MODE (var))))
2060 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2061 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2068 rtx dest = SET_DEST (x);
2069 rtx src = SET_SRC (x);
2071 rtx outerdest = dest;
2074 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2075 || GET_CODE (dest) == SIGN_EXTRACT
2076 || GET_CODE (dest) == ZERO_EXTRACT)
2077 dest = XEXP (dest, 0);
2079 if (GET_CODE (src) == SUBREG)
2080 src = XEXP (src, 0);
2082 /* If VAR does not appear at the top level of the SET
2083 just scan the lower levels of the tree. */
2085 if (src != var && dest != var)
2088 /* We will need to rerecognize this insn. */
2089 INSN_CODE (insn) = -1;
2092 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var)
2094 /* Since this case will return, ensure we fixup all the
2096 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2097 insn, replacements);
2098 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2099 insn, replacements);
2100 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2101 insn, replacements);
2103 tem = XEXP (outerdest, 0);
2105 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2106 that may appear inside a ZERO_EXTRACT.
2107 This was legitimate when the MEM was a REG. */
2108 if (GET_CODE (tem) == SUBREG
2109 && SUBREG_REG (tem) == var)
2110 tem = fixup_memory_subreg (tem, insn, 0);
2112 tem = fixup_stack_1 (tem, insn);
2114 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2115 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2116 && ! mode_dependent_address_p (XEXP (tem, 0))
2117 && ! MEM_VOLATILE_P (tem))
2119 enum machine_mode wanted_mode
2120 = insn_operand_mode[(int) CODE_FOR_insv][0];
2121 enum machine_mode is_mode = GET_MODE (tem);
2122 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2124 /* If we have a narrower mode, we can do something. */
2125 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2127 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2128 rtx old_pos = XEXP (outerdest, 2);
2131 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2132 offset = (GET_MODE_SIZE (is_mode)
2133 - GET_MODE_SIZE (wanted_mode) - offset);
2135 pos %= GET_MODE_BITSIZE (wanted_mode);
2137 newmem = gen_rtx_MEM (wanted_mode,
2138 plus_constant (XEXP (tem, 0), offset));
2139 RTX_UNCHANGING_P (newmem) = RTX_UNCHANGING_P (tem);
2140 MEM_VOLATILE_P (newmem) = MEM_VOLATILE_P (tem);
2141 MEM_IN_STRUCT_P (newmem) = MEM_IN_STRUCT_P (tem);
2143 /* Make the change and see if the insn remains valid. */
2144 INSN_CODE (insn) = -1;
2145 XEXP (outerdest, 0) = newmem;
2146 XEXP (outerdest, 2) = GEN_INT (pos);
2148 if (recog_memoized (insn) >= 0)
2151 /* Otherwise, restore old position. XEXP (x, 0) will be
2153 XEXP (outerdest, 2) = old_pos;
2157 /* If we get here, the bit-field store doesn't allow memory
2158 or isn't located at a constant position. Load the value into
2159 a register, do the store, and put it back into memory. */
2161 tem1 = gen_reg_rtx (GET_MODE (tem));
2162 emit_insn_before (gen_move_insn (tem1, tem), insn);
2163 emit_insn_after (gen_move_insn (tem, tem1), insn);
2164 XEXP (outerdest, 0) = tem1;
2169 /* STRICT_LOW_PART is a no-op on memory references
2170 and it can cause combinations to be unrecognizable,
2173 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2174 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2176 /* A valid insn to copy VAR into or out of a register
2177 must be left alone, to avoid an infinite loop here.
2178 If the reference to VAR is by a subreg, fix that up,
2179 since SUBREG is not valid for a memref.
2180 Also fix up the address of the stack slot.
2182 Note that we must not try to recognize the insn until
2183 after we know that we have valid addresses and no
2184 (subreg (mem ...) ...) constructs, since these interfere
2185 with determining the validity of the insn. */
2187 if ((SET_SRC (x) == var
2188 || (GET_CODE (SET_SRC (x)) == SUBREG
2189 && SUBREG_REG (SET_SRC (x)) == var))
2190 && (GET_CODE (SET_DEST (x)) == REG
2191 || (GET_CODE (SET_DEST (x)) == SUBREG
2192 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2193 && GET_MODE (var) == promoted_mode
2194 && x == single_set (insn))
2198 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2199 if (replacement->new)
2200 SET_SRC (x) = replacement->new;
2201 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2202 SET_SRC (x) = replacement->new
2203 = fixup_memory_subreg (SET_SRC (x), insn, 0);
2205 SET_SRC (x) = replacement->new
2206 = fixup_stack_1 (SET_SRC (x), insn);
2208 if (recog_memoized (insn) >= 0)
2211 /* INSN is not valid, but we know that we want to
2212 copy SET_SRC (x) to SET_DEST (x) in some way. So
2213 we generate the move and see whether it requires more
2214 than one insn. If it does, we emit those insns and
2215 delete INSN. Otherwise, we an just replace the pattern
2216 of INSN; we have already verified above that INSN has
2217 no other function that to do X. */
2219 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2220 if (GET_CODE (pat) == SEQUENCE)
2222 emit_insn_after (pat, insn);
2223 PUT_CODE (insn, NOTE);
2224 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
2225 NOTE_SOURCE_FILE (insn) = 0;
2228 PATTERN (insn) = pat;
2233 if ((SET_DEST (x) == var
2234 || (GET_CODE (SET_DEST (x)) == SUBREG
2235 && SUBREG_REG (SET_DEST (x)) == var))
2236 && (GET_CODE (SET_SRC (x)) == REG
2237 || (GET_CODE (SET_SRC (x)) == SUBREG
2238 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2239 && GET_MODE (var) == promoted_mode
2240 && x == single_set (insn))
2244 if (GET_CODE (SET_DEST (x)) == SUBREG)
2245 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn, 0);
2247 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2249 if (recog_memoized (insn) >= 0)
2252 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2253 if (GET_CODE (pat) == SEQUENCE)
2255 emit_insn_after (pat, insn);
2256 PUT_CODE (insn, NOTE);
2257 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
2258 NOTE_SOURCE_FILE (insn) = 0;
2261 PATTERN (insn) = pat;
2266 /* Otherwise, storing into VAR must be handled specially
2267 by storing into a temporary and copying that into VAR
2268 with a new insn after this one. Note that this case
2269 will be used when storing into a promoted scalar since
2270 the insn will now have different modes on the input
2271 and output and hence will be invalid (except for the case
2272 of setting it to a constant, which does not need any
2273 change if it is valid). We generate extra code in that case,
2274 but combine.c will eliminate it. */
2279 rtx fixeddest = SET_DEST (x);
2281 /* STRICT_LOW_PART can be discarded, around a MEM. */
2282 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2283 fixeddest = XEXP (fixeddest, 0);
2284 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2285 if (GET_CODE (fixeddest) == SUBREG)
2287 fixeddest = fixup_memory_subreg (fixeddest, insn, 0);
2288 promoted_mode = GET_MODE (fixeddest);
2291 fixeddest = fixup_stack_1 (fixeddest, insn);
2293 temp = gen_reg_rtx (promoted_mode);
2295 emit_insn_after (gen_move_insn (fixeddest,
2296 gen_lowpart (GET_MODE (fixeddest),
2300 SET_DEST (x) = temp;
2308 /* Nothing special about this RTX; fix its operands. */
2310 fmt = GET_RTX_FORMAT (code);
2311 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2314 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements);
2318 for (j = 0; j < XVECLEN (x, i); j++)
2319 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2320 insn, replacements);
2325 /* Given X, an rtx of the form (SUBREG:m1 (MEM:m2 addr)),
2326 return an rtx (MEM:m1 newaddr) which is equivalent.
2327 If any insns must be emitted to compute NEWADDR, put them before INSN.
2329 UNCRITICAL nonzero means accept paradoxical subregs.
2330 This is used for subregs found inside REG_NOTES. */
2333 fixup_memory_subreg (x, insn, uncritical)
2338 int offset = SUBREG_WORD (x) * UNITS_PER_WORD;
2339 rtx addr = XEXP (SUBREG_REG (x), 0);
2340 enum machine_mode mode = GET_MODE (x);
2343 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2344 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))
2348 if (BYTES_BIG_ENDIAN)
2349 offset += (MIN (UNITS_PER_WORD, GET_MODE_SIZE (GET_MODE (SUBREG_REG (x))))
2350 - MIN (UNITS_PER_WORD, GET_MODE_SIZE (mode)));
2351 addr = plus_constant (addr, offset);
2352 if (!flag_force_addr && memory_address_p (mode, addr))
2353 /* Shortcut if no insns need be emitted. */
2354 return change_address (SUBREG_REG (x), mode, addr);
2356 result = change_address (SUBREG_REG (x), mode, addr);
2357 emit_insn_before (gen_sequence (), insn);
2362 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2363 Replace subexpressions of X in place.
2364 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2365 Otherwise return X, with its contents possibly altered.
2367 If any insns must be emitted to compute NEWADDR, put them before INSN.
2369 UNCRITICAL is as in fixup_memory_subreg. */
2372 walk_fixup_memory_subreg (x, insn, uncritical)
2377 register enum rtx_code code;
2384 code = GET_CODE (x);
2386 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2387 return fixup_memory_subreg (x, insn, uncritical);
2389 /* Nothing special about this RTX; fix its operands. */
2391 fmt = GET_RTX_FORMAT (code);
2392 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2395 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn, uncritical);
2399 for (j = 0; j < XVECLEN (x, i); j++)
2401 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn, uncritical);
2407 /* For each memory ref within X, if it refers to a stack slot
2408 with an out of range displacement, put the address in a temp register
2409 (emitting new insns before INSN to load these registers)
2410 and alter the memory ref to use that register.
2411 Replace each such MEM rtx with a copy, to avoid clobberage. */
2414 fixup_stack_1 (x, insn)
2419 register RTX_CODE code = GET_CODE (x);
2424 register rtx ad = XEXP (x, 0);
2425 /* If we have address of a stack slot but it's not valid
2426 (displacement is too large), compute the sum in a register. */
2427 if (GET_CODE (ad) == PLUS
2428 && GET_CODE (XEXP (ad, 0)) == REG
2429 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2430 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2431 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2432 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2433 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2435 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2436 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2437 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2438 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2441 if (memory_address_p (GET_MODE (x), ad))
2445 temp = copy_to_reg (ad);
2446 seq = gen_sequence ();
2448 emit_insn_before (seq, insn);
2449 return change_address (x, VOIDmode, temp);
2454 fmt = GET_RTX_FORMAT (code);
2455 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2458 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2462 for (j = 0; j < XVECLEN (x, i); j++)
2463 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2469 /* Optimization: a bit-field instruction whose field
2470 happens to be a byte or halfword in memory
2471 can be changed to a move instruction.
2473 We call here when INSN is an insn to examine or store into a bit-field.
2474 BODY is the SET-rtx to be altered.
2476 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2477 (Currently this is called only from function.c, and EQUIV_MEM
2481 optimize_bit_field (body, insn, equiv_mem)
2486 register rtx bitfield;
2489 enum machine_mode mode;
2491 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2492 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2493 bitfield = SET_DEST (body), destflag = 1;
2495 bitfield = SET_SRC (body), destflag = 0;
2497 /* First check that the field being stored has constant size and position
2498 and is in fact a byte or halfword suitably aligned. */
2500 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2501 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2502 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2504 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2506 register rtx memref = 0;
2508 /* Now check that the containing word is memory, not a register,
2509 and that it is safe to change the machine mode. */
2511 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2512 memref = XEXP (bitfield, 0);
2513 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2515 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2516 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2517 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2518 memref = SUBREG_REG (XEXP (bitfield, 0));
2519 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2521 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2522 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2525 && ! mode_dependent_address_p (XEXP (memref, 0))
2526 && ! MEM_VOLATILE_P (memref))
2528 /* Now adjust the address, first for any subreg'ing
2529 that we are now getting rid of,
2530 and then for which byte of the word is wanted. */
2532 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2535 /* Adjust OFFSET to count bits from low-address byte. */
2536 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2537 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2538 - offset - INTVAL (XEXP (bitfield, 1)));
2540 /* Adjust OFFSET to count bytes from low-address byte. */
2541 offset /= BITS_PER_UNIT;
2542 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2544 offset += SUBREG_WORD (XEXP (bitfield, 0)) * UNITS_PER_WORD;
2545 if (BYTES_BIG_ENDIAN)
2546 offset -= (MIN (UNITS_PER_WORD,
2547 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2548 - MIN (UNITS_PER_WORD,
2549 GET_MODE_SIZE (GET_MODE (memref))));
2553 memref = change_address (memref, mode,
2554 plus_constant (XEXP (memref, 0), offset));
2555 insns = get_insns ();
2557 emit_insns_before (insns, insn);
2559 /* Store this memory reference where
2560 we found the bit field reference. */
2564 validate_change (insn, &SET_DEST (body), memref, 1);
2565 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2567 rtx src = SET_SRC (body);
2568 while (GET_CODE (src) == SUBREG
2569 && SUBREG_WORD (src) == 0)
2570 src = SUBREG_REG (src);
2571 if (GET_MODE (src) != GET_MODE (memref))
2572 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2573 validate_change (insn, &SET_SRC (body), src, 1);
2575 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2576 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2577 /* This shouldn't happen because anything that didn't have
2578 one of these modes should have got converted explicitly
2579 and then referenced through a subreg.
2580 This is so because the original bit-field was
2581 handled by agg_mode and so its tree structure had
2582 the same mode that memref now has. */
2587 rtx dest = SET_DEST (body);
2589 while (GET_CODE (dest) == SUBREG
2590 && SUBREG_WORD (dest) == 0
2591 && (GET_MODE_CLASS (GET_MODE (dest))
2592 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest)))))
2593 dest = SUBREG_REG (dest);
2595 validate_change (insn, &SET_DEST (body), dest, 1);
2597 if (GET_MODE (dest) == GET_MODE (memref))
2598 validate_change (insn, &SET_SRC (body), memref, 1);
2601 /* Convert the mem ref to the destination mode. */
2602 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2605 convert_move (newreg, memref,
2606 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2610 validate_change (insn, &SET_SRC (body), newreg, 1);
2614 /* See if we can convert this extraction or insertion into
2615 a simple move insn. We might not be able to do so if this
2616 was, for example, part of a PARALLEL.
2618 If we succeed, write out any needed conversions. If we fail,
2619 it is hard to guess why we failed, so don't do anything
2620 special; just let the optimization be suppressed. */
2622 if (apply_change_group () && seq)
2623 emit_insns_before (seq, insn);
2628 /* These routines are responsible for converting virtual register references
2629 to the actual hard register references once RTL generation is complete.
2631 The following four variables are used for communication between the
2632 routines. They contain the offsets of the virtual registers from their
2633 respective hard registers. */
2635 static int in_arg_offset;
2636 static int var_offset;
2637 static int dynamic_offset;
2638 static int out_arg_offset;
2640 /* In most machines, the stack pointer register is equivalent to the bottom
2643 #ifndef STACK_POINTER_OFFSET
2644 #define STACK_POINTER_OFFSET 0
2647 /* If not defined, pick an appropriate default for the offset of dynamically
2648 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2649 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2651 #ifndef STACK_DYNAMIC_OFFSET
2653 #ifdef ACCUMULATE_OUTGOING_ARGS
2654 /* The bottom of the stack points to the actual arguments. If
2655 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2656 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2657 stack space for register parameters is not pushed by the caller, but
2658 rather part of the fixed stack areas and hence not included in
2659 `current_function_outgoing_args_size'. Nevertheless, we must allow
2660 for it when allocating stack dynamic objects. */
2662 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2663 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2664 (current_function_outgoing_args_size \
2665 + REG_PARM_STACK_SPACE (FNDECL) + (STACK_POINTER_OFFSET))
2668 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2669 (current_function_outgoing_args_size + (STACK_POINTER_OFFSET))
2673 #define STACK_DYNAMIC_OFFSET(FNDECL) STACK_POINTER_OFFSET
2677 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just had
2678 its address taken. DECL is the decl for the object stored in the
2679 register, for later use if we do need to force REG into the stack.
2680 REG is overwritten by the MEM like in put_reg_into_stack. */
2683 gen_mem_addressof (reg, decl)
2687 tree type = TREE_TYPE (decl);
2689 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)), REGNO (reg));
2690 SET_ADDRESSOF_DECL (r, decl);
2693 PUT_CODE (reg, MEM);
2694 PUT_MODE (reg, DECL_MODE (decl));
2695 MEM_VOLATILE_P (reg) = TREE_SIDE_EFFECTS (decl);
2696 MEM_IN_STRUCT_P (reg) = AGGREGATE_TYPE_P (type);
2698 if (TREE_USED (decl) || DECL_INITIAL (decl) != 0)
2699 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type));
2704 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2707 flush_addressof (decl)
2710 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2711 && DECL_RTL (decl) != 0
2712 && GET_CODE (DECL_RTL (decl)) == MEM
2713 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2714 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2715 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0));
2718 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2721 put_addressof_into_stack (r)
2724 tree decl = ADDRESSOF_DECL (r);
2725 rtx reg = XEXP (r, 0);
2727 if (GET_CODE (reg) != REG)
2730 put_reg_into_stack (0, reg, TREE_TYPE (decl), GET_MODE (reg),
2731 DECL_MODE (decl), TREE_SIDE_EFFECTS (decl),
2732 ADDRESSOF_REGNO (r),
2733 TREE_USED (decl) || DECL_INITIAL (decl) != 0);
2736 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2737 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2741 purge_addressof_1 (loc, insn, force)
2751 /* Re-start here to avoid recursion in common cases. */
2758 code = GET_CODE (x);
2760 if (code == ADDRESSOF && GET_CODE (XEXP (x, 0)) == MEM)
2763 /* We must create a copy of the rtx because it was created by
2764 overwriting a REG rtx which is always shared. */
2765 rtx sub = copy_rtx (XEXP (XEXP (x, 0), 0));
2767 if (validate_change (insn, loc, sub, 0))
2771 if (! validate_change (insn, loc,
2772 force_operand (sub, NULL_RTX),
2776 insns = get_insns ();
2778 emit_insns_before (insns, insn);
2781 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
2783 rtx sub = XEXP (XEXP (x, 0), 0);
2785 if (GET_CODE (sub) == MEM)
2786 sub = gen_rtx_MEM (GET_MODE (x), copy_rtx (XEXP (sub, 0)));
2788 if (GET_CODE (sub) == REG && MEM_VOLATILE_P (x))
2790 put_addressof_into_stack (XEXP (x, 0));
2793 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
2795 if (! BYTES_BIG_ENDIAN && ! WORDS_BIG_ENDIAN)
2797 rtx sub2 = gen_rtx_SUBREG (GET_MODE (x), sub, 0);
2798 if (validate_change (insn, loc, sub2, 0))
2802 else if (validate_change (insn, loc, sub, 0))
2804 /* else give up and put it into the stack */
2806 else if (code == ADDRESSOF)
2808 put_addressof_into_stack (x);
2812 /* Scan all subexpressions. */
2813 fmt = GET_RTX_FORMAT (code);
2814 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
2817 purge_addressof_1 (&XEXP (x, i), insn, force);
2818 else if (*fmt == 'E')
2819 for (j = 0; j < XVECLEN (x, i); j++)
2820 purge_addressof_1 (&XVECEXP (x, i, j), insn, force);
2824 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
2825 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
2829 purge_addressof (insns)
2833 for (insn = insns; insn; insn = NEXT_INSN (insn))
2834 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
2835 || GET_CODE (insn) == CALL_INSN)
2837 purge_addressof_1 (&PATTERN (insn), insn,
2838 asm_noperands (PATTERN (insn)) > 0);
2839 purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0);
2843 /* Pass through the INSNS of function FNDECL and convert virtual register
2844 references to hard register references. */
2847 instantiate_virtual_regs (fndecl, insns)
2854 /* Compute the offsets to use for this function. */
2855 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
2856 var_offset = STARTING_FRAME_OFFSET;
2857 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
2858 out_arg_offset = STACK_POINTER_OFFSET;
2860 /* Scan all variables and parameters of this function. For each that is
2861 in memory, instantiate all virtual registers if the result is a valid
2862 address. If not, we do it later. That will handle most uses of virtual
2863 regs on many machines. */
2864 instantiate_decls (fndecl, 1);
2866 /* Initialize recognition, indicating that volatile is OK. */
2869 /* Scan through all the insns, instantiating every virtual register still
2871 for (insn = insns; insn; insn = NEXT_INSN (insn))
2872 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
2873 || GET_CODE (insn) == CALL_INSN)
2875 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
2876 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
2879 /* Instantiate the stack slots for the parm registers, for later use in
2880 addressof elimination. */
2881 for (i = 0; i < max_parm_reg; ++i)
2882 if (parm_reg_stack_loc[i])
2883 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
2885 /* Now instantiate the remaining register equivalences for debugging info.
2886 These will not be valid addresses. */
2887 instantiate_decls (fndecl, 0);
2889 /* Indicate that, from now on, assign_stack_local should use
2890 frame_pointer_rtx. */
2891 virtuals_instantiated = 1;
2894 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
2895 all virtual registers in their DECL_RTL's.
2897 If VALID_ONLY, do this only if the resulting address is still valid.
2898 Otherwise, always do it. */
2901 instantiate_decls (fndecl, valid_only)
2907 if (DECL_SAVED_INSNS (fndecl))
2908 /* When compiling an inline function, the obstack used for
2909 rtl allocation is the maybepermanent_obstack. Calling
2910 `resume_temporary_allocation' switches us back to that
2911 obstack while we process this function's parameters. */
2912 resume_temporary_allocation ();
2914 /* Process all parameters of the function. */
2915 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
2917 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
2919 instantiate_decl (DECL_RTL (decl), size, valid_only);
2921 /* If the parameter was promoted, then the incoming RTL mode may be
2922 larger than the declared type size. We must use the larger of
2924 size = MAX (GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl))), size);
2925 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
2928 /* Now process all variables defined in the function or its subblocks. */
2929 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
2931 if (DECL_INLINE (fndecl) || DECL_DEFER_OUTPUT (fndecl))
2933 /* Save all rtl allocated for this function by raising the
2934 high-water mark on the maybepermanent_obstack. */
2936 /* All further rtl allocation is now done in the current_obstack. */
2937 rtl_in_current_obstack ();
2941 /* Subroutine of instantiate_decls: Process all decls in the given
2942 BLOCK node and all its subblocks. */
2945 instantiate_decls_1 (let, valid_only)
2951 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
2952 instantiate_decl (DECL_RTL (t), int_size_in_bytes (TREE_TYPE (t)),
2955 /* Process all subblocks. */
2956 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
2957 instantiate_decls_1 (t, valid_only);
2960 /* Subroutine of the preceding procedures: Given RTL representing a
2961 decl and the size of the object, do any instantiation required.
2963 If VALID_ONLY is non-zero, it means that the RTL should only be
2964 changed if the new address is valid. */
2967 instantiate_decl (x, size, valid_only)
2972 enum machine_mode mode;
2975 /* If this is not a MEM, no need to do anything. Similarly if the
2976 address is a constant or a register that is not a virtual register. */
2978 if (x == 0 || GET_CODE (x) != MEM)
2982 if (CONSTANT_P (addr)
2983 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
2984 || (GET_CODE (addr) == REG
2985 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
2986 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
2989 /* If we should only do this if the address is valid, copy the address.
2990 We need to do this so we can undo any changes that might make the
2991 address invalid. This copy is unfortunate, but probably can't be
2995 addr = copy_rtx (addr);
2997 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3001 /* Now verify that the resulting address is valid for every integer or
3002 floating-point mode up to and including SIZE bytes long. We do this
3003 since the object might be accessed in any mode and frame addresses
3006 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3007 mode != VOIDmode && GET_MODE_SIZE (mode) <= size;
3008 mode = GET_MODE_WIDER_MODE (mode))
3009 if (! memory_address_p (mode, addr))
3012 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3013 mode != VOIDmode && GET_MODE_SIZE (mode) <= size;
3014 mode = GET_MODE_WIDER_MODE (mode))
3015 if (! memory_address_p (mode, addr))
3019 /* Put back the address now that we have updated it and we either know
3020 it is valid or we don't care whether it is valid. */
3025 /* Given a pointer to a piece of rtx and an optional pointer to the
3026 containing object, instantiate any virtual registers present in it.
3028 If EXTRA_INSNS, we always do the replacement and generate
3029 any extra insns before OBJECT. If it zero, we do nothing if replacement
3032 Return 1 if we either had nothing to do or if we were able to do the
3033 needed replacement. Return 0 otherwise; we only return zero if
3034 EXTRA_INSNS is zero.
3036 We first try some simple transformations to avoid the creation of extra
3040 instantiate_virtual_regs_1 (loc, object, extra_insns)
3048 HOST_WIDE_INT offset;
3054 /* Re-start here to avoid recursion in common cases. */
3061 code = GET_CODE (x);
3063 /* Check for some special cases. */
3080 /* We are allowed to set the virtual registers. This means that
3081 that the actual register should receive the source minus the
3082 appropriate offset. This is used, for example, in the handling
3083 of non-local gotos. */
3084 if (SET_DEST (x) == virtual_incoming_args_rtx)
3085 new = arg_pointer_rtx, offset = - in_arg_offset;
3086 else if (SET_DEST (x) == virtual_stack_vars_rtx)
3087 new = frame_pointer_rtx, offset = - var_offset;
3088 else if (SET_DEST (x) == virtual_stack_dynamic_rtx)
3089 new = stack_pointer_rtx, offset = - dynamic_offset;
3090 else if (SET_DEST (x) == virtual_outgoing_args_rtx)
3091 new = stack_pointer_rtx, offset = - out_arg_offset;
3095 /* The only valid sources here are PLUS or REG. Just do
3096 the simplest possible thing to handle them. */
3097 if (GET_CODE (SET_SRC (x)) != REG
3098 && GET_CODE (SET_SRC (x)) != PLUS)
3102 if (GET_CODE (SET_SRC (x)) != REG)
3103 temp = force_operand (SET_SRC (x), NULL_RTX);
3106 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3110 emit_insns_before (seq, object);
3113 if (! validate_change (object, &SET_SRC (x), temp, 0)
3120 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3125 /* Handle special case of virtual register plus constant. */
3126 if (CONSTANT_P (XEXP (x, 1)))
3128 rtx old, new_offset;
3130 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3131 if (GET_CODE (XEXP (x, 0)) == PLUS)
3133 rtx inner = XEXP (XEXP (x, 0), 0);
3135 if (inner == virtual_incoming_args_rtx)
3136 new = arg_pointer_rtx, offset = in_arg_offset;
3137 else if (inner == virtual_stack_vars_rtx)
3138 new = frame_pointer_rtx, offset = var_offset;
3139 else if (inner == virtual_stack_dynamic_rtx)
3140 new = stack_pointer_rtx, offset = dynamic_offset;
3141 else if (inner == virtual_outgoing_args_rtx)
3142 new = stack_pointer_rtx, offset = out_arg_offset;
3149 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3151 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3154 else if (XEXP (x, 0) == virtual_incoming_args_rtx)
3155 new = arg_pointer_rtx, offset = in_arg_offset;
3156 else if (XEXP (x, 0) == virtual_stack_vars_rtx)
3157 new = frame_pointer_rtx, offset = var_offset;
3158 else if (XEXP (x, 0) == virtual_stack_dynamic_rtx)
3159 new = stack_pointer_rtx, offset = dynamic_offset;
3160 else if (XEXP (x, 0) == virtual_outgoing_args_rtx)
3161 new = stack_pointer_rtx, offset = out_arg_offset;
3164 /* We know the second operand is a constant. Unless the
3165 first operand is a REG (which has been already checked),
3166 it needs to be checked. */
3167 if (GET_CODE (XEXP (x, 0)) != REG)
3175 new_offset = plus_constant (XEXP (x, 1), offset);
3177 /* If the new constant is zero, try to replace the sum with just
3179 if (new_offset == const0_rtx
3180 && validate_change (object, loc, new, 0))
3183 /* Next try to replace the register and new offset.
3184 There are two changes to validate here and we can't assume that
3185 in the case of old offset equals new just changing the register
3186 will yield a valid insn. In the interests of a little efficiency,
3187 however, we only call validate change once (we don't queue up the
3188 changes and then call apply_change_group). */
3192 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3193 : (XEXP (x, 0) = new,
3194 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3202 /* Otherwise copy the new constant into a register and replace
3203 constant with that register. */
3204 temp = gen_reg_rtx (Pmode);
3206 if (validate_change (object, &XEXP (x, 1), temp, 0))
3207 emit_insn_before (gen_move_insn (temp, new_offset), object);
3210 /* If that didn't work, replace this expression with a
3211 register containing the sum. */
3214 new = gen_rtx_PLUS (Pmode, new, new_offset);
3217 temp = force_operand (new, NULL_RTX);
3221 emit_insns_before (seq, object);
3222 if (! validate_change (object, loc, temp, 0)
3223 && ! validate_replace_rtx (x, temp, object))
3231 /* Fall through to generic two-operand expression case. */
3237 case DIV: case UDIV:
3238 case MOD: case UMOD:
3239 case AND: case IOR: case XOR:
3240 case ROTATERT: case ROTATE:
3241 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3243 case GE: case GT: case GEU: case GTU:
3244 case LE: case LT: case LEU: case LTU:
3245 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3246 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3251 /* Most cases of MEM that convert to valid addresses have already been
3252 handled by our scan of decls. The only special handling we
3253 need here is to make a copy of the rtx to ensure it isn't being
3254 shared if we have to change it to a pseudo.
3256 If the rtx is a simple reference to an address via a virtual register,
3257 it can potentially be shared. In such cases, first try to make it
3258 a valid address, which can also be shared. Otherwise, copy it and
3261 First check for common cases that need no processing. These are
3262 usually due to instantiation already being done on a previous instance
3266 if (CONSTANT_ADDRESS_P (temp)
3267 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3268 || temp == arg_pointer_rtx
3270 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3271 || temp == hard_frame_pointer_rtx
3273 || temp == frame_pointer_rtx)
3276 if (GET_CODE (temp) == PLUS
3277 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3278 && (XEXP (temp, 0) == frame_pointer_rtx
3279 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3280 || XEXP (temp, 0) == hard_frame_pointer_rtx
3282 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3283 || XEXP (temp, 0) == arg_pointer_rtx
3288 if (temp == virtual_stack_vars_rtx
3289 || temp == virtual_incoming_args_rtx
3290 || (GET_CODE (temp) == PLUS
3291 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3292 && (XEXP (temp, 0) == virtual_stack_vars_rtx
3293 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
3295 /* This MEM may be shared. If the substitution can be done without
3296 the need to generate new pseudos, we want to do it in place
3297 so all copies of the shared rtx benefit. The call below will
3298 only make substitutions if the resulting address is still
3301 Note that we cannot pass X as the object in the recursive call
3302 since the insn being processed may not allow all valid
3303 addresses. However, if we were not passed on object, we can
3304 only modify X without copying it if X will have a valid
3307 ??? Also note that this can still lose if OBJECT is an insn that
3308 has less restrictions on an address that some other insn.
3309 In that case, we will modify the shared address. This case
3310 doesn't seem very likely, though. One case where this could
3311 happen is in the case of a USE or CLOBBER reference, but we
3312 take care of that below. */
3314 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
3315 object ? object : x, 0))
3318 /* Otherwise make a copy and process that copy. We copy the entire
3319 RTL expression since it might be a PLUS which could also be
3321 *loc = x = copy_rtx (x);
3324 /* Fall through to generic unary operation case. */
3326 case STRICT_LOW_PART:
3328 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
3329 case SIGN_EXTEND: case ZERO_EXTEND:
3330 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
3331 case FLOAT: case FIX:
3332 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
3336 /* These case either have just one operand or we know that we need not
3337 check the rest of the operands. */
3343 /* If the operand is a MEM, see if the change is a valid MEM. If not,
3344 go ahead and make the invalid one, but do it to a copy. For a REG,
3345 just make the recursive call, since there's no chance of a problem. */
3347 if ((GET_CODE (XEXP (x, 0)) == MEM
3348 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
3350 || (GET_CODE (XEXP (x, 0)) == REG
3351 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
3354 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
3359 /* Try to replace with a PLUS. If that doesn't work, compute the sum
3360 in front of this insn and substitute the temporary. */
3361 if (x == virtual_incoming_args_rtx)
3362 new = arg_pointer_rtx, offset = in_arg_offset;
3363 else if (x == virtual_stack_vars_rtx)
3364 new = frame_pointer_rtx, offset = var_offset;
3365 else if (x == virtual_stack_dynamic_rtx)
3366 new = stack_pointer_rtx, offset = dynamic_offset;
3367 else if (x == virtual_outgoing_args_rtx)
3368 new = stack_pointer_rtx, offset = out_arg_offset;
3372 temp = plus_constant (new, offset);
3373 if (!validate_change (object, loc, temp, 0))
3379 temp = force_operand (temp, NULL_RTX);
3383 emit_insns_before (seq, object);
3384 if (! validate_change (object, loc, temp, 0)
3385 && ! validate_replace_rtx (x, temp, object))
3393 if (GET_CODE (XEXP (x, 0)) == REG)
3396 else if (GET_CODE (XEXP (x, 0)) == MEM)
3398 /* If we have a (addressof (mem ..)), do any instantiation inside
3399 since we know we'll be making the inside valid when we finally
3400 remove the ADDRESSOF. */
3401 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
3410 /* Scan all subexpressions. */
3411 fmt = GET_RTX_FORMAT (code);
3412 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3415 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
3418 else if (*fmt == 'E')
3419 for (j = 0; j < XVECLEN (x, i); j++)
3420 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
3427 /* Optimization: assuming this function does not receive nonlocal gotos,
3428 delete the handlers for such, as well as the insns to establish
3429 and disestablish them. */
3435 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3437 /* Delete the handler by turning off the flag that would
3438 prevent jump_optimize from deleting it.
3439 Also permit deletion of the nonlocal labels themselves
3440 if nothing local refers to them. */
3441 if (GET_CODE (insn) == CODE_LABEL)
3445 LABEL_PRESERVE_P (insn) = 0;
3447 /* Remove it from the nonlocal_label list, to avoid confusing
3449 for (t = nonlocal_labels, last_t = 0; t;
3450 last_t = t, t = TREE_CHAIN (t))
3451 if (DECL_RTL (TREE_VALUE (t)) == insn)
3456 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
3458 TREE_CHAIN (last_t) = TREE_CHAIN (t);
3461 if (GET_CODE (insn) == INSN
3462 && ((nonlocal_goto_handler_slot != 0
3463 && reg_mentioned_p (nonlocal_goto_handler_slot, PATTERN (insn)))
3464 || (nonlocal_goto_stack_level != 0
3465 && reg_mentioned_p (nonlocal_goto_stack_level,
3471 /* Return a list (chain of EXPR_LIST nodes) for the nonlocal labels
3472 of the current function. */
3475 nonlocal_label_rtx_list ()
3480 for (t = nonlocal_labels; t; t = TREE_CHAIN (t))
3481 x = gen_rtx_EXPR_LIST (VOIDmode, label_rtx (TREE_VALUE (t)), x);
3486 /* Output a USE for any register use in RTL.
3487 This is used with -noreg to mark the extent of lifespan
3488 of any registers used in a user-visible variable's DECL_RTL. */
3494 if (GET_CODE (rtl) == REG)
3495 /* This is a register variable. */
3496 emit_insn (gen_rtx_USE (VOIDmode, rtl));
3497 else if (GET_CODE (rtl) == MEM
3498 && GET_CODE (XEXP (rtl, 0)) == REG
3499 && (REGNO (XEXP (rtl, 0)) < FIRST_VIRTUAL_REGISTER
3500 || REGNO (XEXP (rtl, 0)) > LAST_VIRTUAL_REGISTER)
3501 && XEXP (rtl, 0) != current_function_internal_arg_pointer)
3502 /* This is a variable-sized structure. */
3503 emit_insn (gen_rtx_USE (VOIDmode, XEXP (rtl, 0)));
3506 /* Like use_variable except that it outputs the USEs after INSN
3507 instead of at the end of the insn-chain. */
3510 use_variable_after (rtl, insn)
3513 if (GET_CODE (rtl) == REG)
3514 /* This is a register variable. */
3515 emit_insn_after (gen_rtx_USE (VOIDmode, rtl), insn);
3516 else if (GET_CODE (rtl) == MEM
3517 && GET_CODE (XEXP (rtl, 0)) == REG
3518 && (REGNO (XEXP (rtl, 0)) < FIRST_VIRTUAL_REGISTER
3519 || REGNO (XEXP (rtl, 0)) > LAST_VIRTUAL_REGISTER)
3520 && XEXP (rtl, 0) != current_function_internal_arg_pointer)
3521 /* This is a variable-sized structure. */
3522 emit_insn_after (gen_rtx_USE (VOIDmode, XEXP (rtl, 0)), insn);
3528 return max_parm_reg;
3531 /* Return the first insn following those generated by `assign_parms'. */
3534 get_first_nonparm_insn ()
3537 return NEXT_INSN (last_parm_insn);
3538 return get_insns ();
3541 /* Return the first NOTE_INSN_BLOCK_BEG note in the function.
3542 Crash if there is none. */
3545 get_first_block_beg ()
3547 register rtx searcher;
3548 register rtx insn = get_first_nonparm_insn ();
3550 for (searcher = insn; searcher; searcher = NEXT_INSN (searcher))
3551 if (GET_CODE (searcher) == NOTE
3552 && NOTE_LINE_NUMBER (searcher) == NOTE_INSN_BLOCK_BEG)
3555 abort (); /* Invalid call to this function. (See comments above.) */
3559 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
3560 This means a type for which function calls must pass an address to the
3561 function or get an address back from the function.
3562 EXP may be a type node or an expression (whose type is tested). */
3565 aggregate_value_p (exp)
3568 int i, regno, nregs;
3571 if (TREE_CODE_CLASS (TREE_CODE (exp)) == 't')
3574 type = TREE_TYPE (exp);
3576 if (RETURN_IN_MEMORY (type))
3578 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
3579 and thus can't be returned in registers. */
3580 if (TREE_ADDRESSABLE (type))
3582 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
3584 /* Make sure we have suitable call-clobbered regs to return
3585 the value in; if not, we must return it in memory. */
3586 reg = hard_function_value (type, 0);
3588 /* If we have something other than a REG (e.g. a PARALLEL), then assume
3590 if (GET_CODE (reg) != REG)
3593 regno = REGNO (reg);
3594 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
3595 for (i = 0; i < nregs; i++)
3596 if (! call_used_regs[regno + i])
3601 /* Assign RTL expressions to the function's parameters.
3602 This may involve copying them into registers and using
3603 those registers as the RTL for them.
3605 If SECOND_TIME is non-zero it means that this function is being
3606 called a second time. This is done by integrate.c when a function's
3607 compilation is deferred. We need to come back here in case the
3608 FUNCTION_ARG macro computes items needed for the rest of the compilation
3609 (such as changing which registers are fixed or caller-saved). But suppress
3610 writing any insns or setting DECL_RTL of anything in this case. */
3613 assign_parms (fndecl, second_time)
3618 register rtx entry_parm = 0;
3619 register rtx stack_parm = 0;
3620 CUMULATIVE_ARGS args_so_far;
3621 enum machine_mode promoted_mode, passed_mode;
3622 enum machine_mode nominal_mode, promoted_nominal_mode;
3624 /* Total space needed so far for args on the stack,
3625 given as a constant and a tree-expression. */
3626 struct args_size stack_args_size;
3627 tree fntype = TREE_TYPE (fndecl);
3628 tree fnargs = DECL_ARGUMENTS (fndecl);
3629 /* This is used for the arg pointer when referring to stack args. */
3630 rtx internal_arg_pointer;
3631 /* This is a dummy PARM_DECL that we used for the function result if
3632 the function returns a structure. */
3633 tree function_result_decl = 0;
3634 int varargs_setup = 0;
3635 rtx conversion_insns = 0;
3637 /* Nonzero if the last arg is named `__builtin_va_alist',
3638 which is used on some machines for old-fashioned non-ANSI varargs.h;
3639 this should be stuck onto the stack as if it had arrived there. */
3641 = (current_function_varargs
3643 && (parm = tree_last (fnargs)) != 0
3645 && (! strcmp (IDENTIFIER_POINTER (DECL_NAME (parm)),
3646 "__builtin_va_alist")));
3648 /* Nonzero if function takes extra anonymous args.
3649 This means the last named arg must be on the stack
3650 right before the anonymous ones. */
3652 = (TYPE_ARG_TYPES (fntype) != 0
3653 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
3654 != void_type_node));
3656 current_function_stdarg = stdarg;
3658 /* If the reg that the virtual arg pointer will be translated into is
3659 not a fixed reg or is the stack pointer, make a copy of the virtual
3660 arg pointer, and address parms via the copy. The frame pointer is
3661 considered fixed even though it is not marked as such.
3663 The second time through, simply use ap to avoid generating rtx. */
3665 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
3666 || ! (fixed_regs[ARG_POINTER_REGNUM]
3667 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM))
3669 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
3671 internal_arg_pointer = virtual_incoming_args_rtx;
3672 current_function_internal_arg_pointer = internal_arg_pointer;
3674 stack_args_size.constant = 0;
3675 stack_args_size.var = 0;
3677 /* If struct value address is treated as the first argument, make it so. */
3678 if (aggregate_value_p (DECL_RESULT (fndecl))
3679 && ! current_function_returns_pcc_struct
3680 && struct_value_incoming_rtx == 0)
3682 tree type = build_pointer_type (TREE_TYPE (fntype));
3684 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
3686 DECL_ARG_TYPE (function_result_decl) = type;
3687 TREE_CHAIN (function_result_decl) = fnargs;
3688 fnargs = function_result_decl;
3691 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
3692 parm_reg_stack_loc = (rtx *) savealloc (max_parm_reg * sizeof (rtx));
3693 bzero ((char *) parm_reg_stack_loc, max_parm_reg * sizeof (rtx));
3695 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
3696 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
3698 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, 0);
3701 /* We haven't yet found an argument that we must push and pretend the
3703 current_function_pretend_args_size = 0;
3705 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
3707 int aggregate = AGGREGATE_TYPE_P (TREE_TYPE (parm));
3708 struct args_size stack_offset;
3709 struct args_size arg_size;
3710 int passed_pointer = 0;
3711 int did_conversion = 0;
3712 tree passed_type = DECL_ARG_TYPE (parm);
3713 tree nominal_type = TREE_TYPE (parm);
3715 /* Set LAST_NAMED if this is last named arg before some
3717 int last_named = ((TREE_CHAIN (parm) == 0
3718 || DECL_NAME (TREE_CHAIN (parm)) == 0)
3719 && (stdarg || current_function_varargs));
3720 /* Set NAMED_ARG if this arg should be treated as a named arg. For
3721 most machines, if this is a varargs/stdarg function, then we treat
3722 the last named arg as if it were anonymous too. */
3723 int named_arg = STRICT_ARGUMENT_NAMING ? 1 : ! last_named;
3725 if (TREE_TYPE (parm) == error_mark_node
3726 /* This can happen after weird syntax errors
3727 or if an enum type is defined among the parms. */
3728 || TREE_CODE (parm) != PARM_DECL
3729 || passed_type == NULL)
3731 DECL_INCOMING_RTL (parm) = DECL_RTL (parm)
3732 = gen_rtx_MEM (BLKmode, const0_rtx);
3733 TREE_USED (parm) = 1;
3737 /* For varargs.h function, save info about regs and stack space
3738 used by the individual args, not including the va_alist arg. */
3739 if (hide_last_arg && last_named)
3740 current_function_args_info = args_so_far;
3742 /* Find mode of arg as it is passed, and mode of arg
3743 as it should be during execution of this function. */
3744 passed_mode = TYPE_MODE (passed_type);
3745 nominal_mode = TYPE_MODE (nominal_type);
3747 /* If the parm's mode is VOID, its value doesn't matter,
3748 and avoid the usual things like emit_move_insn that could crash. */
3749 if (nominal_mode == VOIDmode)
3751 DECL_INCOMING_RTL (parm) = DECL_RTL (parm) = const0_rtx;
3755 /* If the parm is to be passed as a transparent union, use the
3756 type of the first field for the tests below. We have already
3757 verified that the modes are the same. */
3758 if (DECL_TRANSPARENT_UNION (parm)
3759 || TYPE_TRANSPARENT_UNION (passed_type))
3760 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
3762 /* See if this arg was passed by invisible reference. It is if
3763 it is an object whose size depends on the contents of the
3764 object itself or if the machine requires these objects be passed
3767 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
3768 && contains_placeholder_p (TYPE_SIZE (passed_type)))
3769 || TREE_ADDRESSABLE (passed_type)
3770 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3771 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
3772 passed_type, named_arg)
3776 passed_type = nominal_type = build_pointer_type (passed_type);
3778 passed_mode = nominal_mode = Pmode;
3781 promoted_mode = passed_mode;
3783 #ifdef PROMOTE_FUNCTION_ARGS
3784 /* Compute the mode in which the arg is actually extended to. */
3785 unsignedp = TREE_UNSIGNED (passed_type);
3786 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
3789 /* Let machine desc say which reg (if any) the parm arrives in.
3790 0 means it arrives on the stack. */
3791 #ifdef FUNCTION_INCOMING_ARG
3792 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
3793 passed_type, named_arg);
3795 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
3796 passed_type, named_arg);
3799 if (entry_parm == 0)
3800 promoted_mode = passed_mode;
3802 #ifdef SETUP_INCOMING_VARARGS
3803 /* If this is the last named parameter, do any required setup for
3804 varargs or stdargs. We need to know about the case of this being an
3805 addressable type, in which case we skip the registers it
3806 would have arrived in.
3808 For stdargs, LAST_NAMED will be set for two parameters, the one that
3809 is actually the last named, and the dummy parameter. We only
3810 want to do this action once.
3812 Also, indicate when RTL generation is to be suppressed. */
3813 if (last_named && !varargs_setup)
3815 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
3816 current_function_pretend_args_size,
3822 /* Determine parm's home in the stack,
3823 in case it arrives in the stack or we should pretend it did.
3825 Compute the stack position and rtx where the argument arrives
3828 There is one complexity here: If this was a parameter that would
3829 have been passed in registers, but wasn't only because it is
3830 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
3831 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
3832 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
3833 0 as it was the previous time. */
3835 locate_and_pad_parm (promoted_mode, passed_type,
3836 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3839 #ifdef FUNCTION_INCOMING_ARG
3840 FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
3843 || varargs_setup)) != 0,
3845 FUNCTION_ARG (args_so_far, promoted_mode,
3847 named_arg || varargs_setup) != 0,
3850 fndecl, &stack_args_size, &stack_offset, &arg_size);
3854 rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
3856 if (offset_rtx == const0_rtx)
3857 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
3859 stack_parm = gen_rtx_MEM (promoted_mode,
3860 gen_rtx_PLUS (Pmode,
3861 internal_arg_pointer,
3864 /* If this is a memory ref that contains aggregate components,
3865 mark it as such for cse and loop optimize. Likewise if it
3867 MEM_IN_STRUCT_P (stack_parm) = aggregate;
3868 RTX_UNCHANGING_P (stack_parm) = TREE_READONLY (parm);
3871 /* If this parameter was passed both in registers and in the stack,
3872 use the copy on the stack. */
3873 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
3876 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3877 /* If this parm was passed part in regs and part in memory,
3878 pretend it arrived entirely in memory
3879 by pushing the register-part onto the stack.
3881 In the special case of a DImode or DFmode that is split,
3882 we could put it together in a pseudoreg directly,
3883 but for now that's not worth bothering with. */
3887 int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
3888 passed_type, named_arg);
3892 current_function_pretend_args_size
3893 = (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
3894 / (PARM_BOUNDARY / BITS_PER_UNIT)
3895 * (PARM_BOUNDARY / BITS_PER_UNIT));
3899 /* Handle calls that pass values in multiple non-contiguous
3900 locations. The Irix 6 ABI has examples of this. */
3901 if (GET_CODE (entry_parm) == PARALLEL)
3902 emit_group_store (validize_mem (stack_parm),
3905 move_block_from_reg (REGNO (entry_parm),
3906 validize_mem (stack_parm), nregs,
3907 int_size_in_bytes (TREE_TYPE (parm)));
3909 entry_parm = stack_parm;
3914 /* If we didn't decide this parm came in a register,
3915 by default it came on the stack. */
3916 if (entry_parm == 0)
3917 entry_parm = stack_parm;
3919 /* Record permanently how this parm was passed. */
3921 DECL_INCOMING_RTL (parm) = entry_parm;
3923 /* If there is actually space on the stack for this parm,
3924 count it in stack_args_size; otherwise set stack_parm to 0
3925 to indicate there is no preallocated stack slot for the parm. */
3927 if (entry_parm == stack_parm
3928 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
3929 /* On some machines, even if a parm value arrives in a register
3930 there is still an (uninitialized) stack slot allocated for it.
3932 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
3933 whether this parameter already has a stack slot allocated,
3934 because an arg block exists only if current_function_args_size
3935 is larger than some threshold, and we haven't calculated that
3936 yet. So, for now, we just assume that stack slots never exist
3938 || REG_PARM_STACK_SPACE (fndecl) > 0
3942 stack_args_size.constant += arg_size.constant;
3944 ADD_PARM_SIZE (stack_args_size, arg_size.var);
3947 /* No stack slot was pushed for this parm. */
3950 /* Update info on where next arg arrives in registers. */
3952 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
3953 passed_type, named_arg);
3955 /* If this is our second time through, we are done with this parm. */
3959 /* If we can't trust the parm stack slot to be aligned enough
3960 for its ultimate type, don't use that slot after entry.
3961 We'll make another stack slot, if we need one. */
3963 int thisparm_boundary
3964 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
3966 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
3970 /* If parm was passed in memory, and we need to convert it on entry,
3971 don't store it back in that same slot. */
3973 && nominal_mode != BLKmode && nominal_mode != passed_mode)
3977 /* Now adjust STACK_PARM to the mode and precise location
3978 where this parameter should live during execution,
3979 if we discover that it must live in the stack during execution.
3980 To make debuggers happier on big-endian machines, we store
3981 the value in the last bytes of the space available. */
3983 if (nominal_mode != BLKmode && nominal_mode != passed_mode
3988 if (BYTES_BIG_ENDIAN
3989 && GET_MODE_SIZE (nominal_mode) < UNITS_PER_WORD)
3990 stack_offset.constant += (GET_MODE_SIZE (passed_mode)
3991 - GET_MODE_SIZE (nominal_mode));
3993 offset_rtx = ARGS_SIZE_RTX (stack_offset);
3994 if (offset_rtx == const0_rtx)
3995 stack_parm = gen_rtx_MEM (nominal_mode, internal_arg_pointer);
3997 stack_parm = gen_rtx_MEM (nominal_mode,
3998 gen_rtx_PLUS (Pmode,
3999 internal_arg_pointer,
4002 /* If this is a memory ref that contains aggregate components,
4003 mark it as such for cse and loop optimize. */
4004 MEM_IN_STRUCT_P (stack_parm) = aggregate;
4009 /* We need this "use" info, because the gcc-register->stack-register
4010 converter in reg-stack.c needs to know which registers are active
4011 at the start of the function call. The actual parameter loading
4012 instructions are not always available then anymore, since they might
4013 have been optimised away. */
4015 if (GET_CODE (entry_parm) == REG && !(hide_last_arg && last_named))
4016 emit_insn (gen_rtx_USE (GET_MODE (entry_parm), entry_parm));
4019 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4020 in the mode in which it arrives.
4021 STACK_PARM is an RTX for a stack slot where the parameter can live
4022 during the function (in case we want to put it there).
4023 STACK_PARM is 0 if no stack slot was pushed for it.
4025 Now output code if necessary to convert ENTRY_PARM to
4026 the type in which this function declares it,
4027 and store that result in an appropriate place,
4028 which may be a pseudo reg, may be STACK_PARM,
4029 or may be a local stack slot if STACK_PARM is 0.
4031 Set DECL_RTL to that place. */
4033 if (nominal_mode == BLKmode || GET_CODE (entry_parm) == PARALLEL)
4035 /* If a BLKmode arrives in registers, copy it to a stack slot.
4036 Handle calls that pass values in multiple non-contiguous
4037 locations. The Irix 6 ABI has examples of this. */
4038 if (GET_CODE (entry_parm) == REG
4039 || GET_CODE (entry_parm) == PARALLEL)
4042 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
4045 /* Note that we will be storing an integral number of words.
4046 So we have to be careful to ensure that we allocate an
4047 integral number of words. We do this below in the
4048 assign_stack_local if space was not allocated in the argument
4049 list. If it was, this will not work if PARM_BOUNDARY is not
4050 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4051 if it becomes a problem. */
4053 if (stack_parm == 0)
4056 = assign_stack_local (GET_MODE (entry_parm),
4059 /* If this is a memory ref that contains aggregate
4060 components, mark it as such for cse and loop optimize. */
4061 MEM_IN_STRUCT_P (stack_parm) = aggregate;
4064 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4067 if (TREE_READONLY (parm))
4068 RTX_UNCHANGING_P (stack_parm) = 1;
4070 /* Handle calls that pass values in multiple non-contiguous
4071 locations. The Irix 6 ABI has examples of this. */
4072 if (GET_CODE (entry_parm) == PARALLEL)
4073 emit_group_store (validize_mem (stack_parm), entry_parm);
4075 move_block_from_reg (REGNO (entry_parm),
4076 validize_mem (stack_parm),
4077 size_stored / UNITS_PER_WORD,
4078 int_size_in_bytes (TREE_TYPE (parm)));
4080 DECL_RTL (parm) = stack_parm;
4082 else if (! ((obey_regdecls && ! DECL_REGISTER (parm)
4083 && ! DECL_INLINE (fndecl))
4084 /* layout_decl may set this. */
4085 || TREE_ADDRESSABLE (parm)
4086 || TREE_SIDE_EFFECTS (parm)
4087 /* If -ffloat-store specified, don't put explicit
4088 float variables into registers. */
4089 || (flag_float_store
4090 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4091 /* Always assign pseudo to structure return or item passed
4092 by invisible reference. */
4093 || passed_pointer || parm == function_result_decl)
4095 /* Store the parm in a pseudoregister during the function, but we
4096 may need to do it in a wider mode. */
4098 register rtx parmreg;
4099 int regno, regnoi = 0, regnor = 0;
4101 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4103 promoted_nominal_mode
4104 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4106 parmreg = gen_reg_rtx (promoted_nominal_mode);
4107 mark_user_reg (parmreg);
4109 /* If this was an item that we received a pointer to, set DECL_RTL
4114 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)), parmreg);
4115 MEM_IN_STRUCT_P (DECL_RTL (parm)) = aggregate;
4118 DECL_RTL (parm) = parmreg;
4120 /* Copy the value into the register. */
4121 if (nominal_mode != passed_mode
4122 || promoted_nominal_mode != promoted_mode)
4124 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4125 mode, by the caller. We now have to convert it to
4126 NOMINAL_MODE, if different. However, PARMREG may be in
4127 a different mode than NOMINAL_MODE if it is being stored
4130 If ENTRY_PARM is a hard register, it might be in a register
4131 not valid for operating in its mode (e.g., an odd-numbered
4132 register for a DFmode). In that case, moves are the only
4133 thing valid, so we can't do a convert from there. This
4134 occurs when the calling sequence allow such misaligned
4137 In addition, the conversion may involve a call, which could
4138 clobber parameters which haven't been copied to pseudo
4139 registers yet. Therefore, we must first copy the parm to
4140 a pseudo reg here, and save the conversion until after all
4141 parameters have been moved. */
4143 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4145 emit_move_insn (tempreg, validize_mem (entry_parm));
4147 push_to_sequence (conversion_insns);
4148 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4150 expand_assignment (parm,
4151 make_tree (nominal_type, tempreg), 0, 0);
4152 conversion_insns = get_insns ();
4157 emit_move_insn (parmreg, validize_mem (entry_parm));
4159 /* If we were passed a pointer but the actual value
4160 can safely live in a register, put it in one. */
4161 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4162 && ! ((obey_regdecls && ! DECL_REGISTER (parm)
4163 && ! DECL_INLINE (fndecl))
4164 /* layout_decl may set this. */
4165 || TREE_ADDRESSABLE (parm)
4166 || TREE_SIDE_EFFECTS (parm)
4167 /* If -ffloat-store specified, don't put explicit
4168 float variables into registers. */
4169 || (flag_float_store
4170 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE)))
4172 /* We can't use nominal_mode, because it will have been set to
4173 Pmode above. We must use the actual mode of the parm. */
4174 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4175 mark_user_reg (parmreg);
4176 emit_move_insn (parmreg, DECL_RTL (parm));
4177 DECL_RTL (parm) = parmreg;
4178 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4182 #ifdef FUNCTION_ARG_CALLEE_COPIES
4183 /* If we are passed an arg by reference and it is our responsibility
4184 to make a copy, do it now.
4185 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4186 original argument, so we must recreate them in the call to
4187 FUNCTION_ARG_CALLEE_COPIES. */
4188 /* ??? Later add code to handle the case that if the argument isn't
4189 modified, don't do the copy. */
4191 else if (passed_pointer
4192 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4193 TYPE_MODE (DECL_ARG_TYPE (parm)),
4194 DECL_ARG_TYPE (parm),
4196 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4199 tree type = DECL_ARG_TYPE (parm);
4201 /* This sequence may involve a library call perhaps clobbering
4202 registers that haven't been copied to pseudos yet. */
4204 push_to_sequence (conversion_insns);
4206 if (TYPE_SIZE (type) == 0
4207 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4208 /* This is a variable sized object. */
4209 copy = gen_rtx_MEM (BLKmode,
4210 allocate_dynamic_stack_space
4211 (expr_size (parm), NULL_RTX,
4212 TYPE_ALIGN (type)));
4214 copy = assign_stack_temp (TYPE_MODE (type),
4215 int_size_in_bytes (type), 1);
4216 MEM_IN_STRUCT_P (copy) = AGGREGATE_TYPE_P (type);
4217 RTX_UNCHANGING_P (copy) = TREE_READONLY (parm);
4219 store_expr (parm, copy, 0);
4220 emit_move_insn (parmreg, XEXP (copy, 0));
4221 if (flag_check_memory_usage)
4222 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
4223 XEXP (copy, 0), ptr_mode,
4224 GEN_INT (int_size_in_bytes (type)),
4225 TYPE_MODE (sizetype),
4226 GEN_INT (MEMORY_USE_RW),
4227 TYPE_MODE (integer_type_node));
4228 conversion_insns = get_insns ();
4232 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4234 /* In any case, record the parm's desired stack location
4235 in case we later discover it must live in the stack.
4237 If it is a COMPLEX value, store the stack location for both
4240 if (GET_CODE (parmreg) == CONCAT)
4241 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4243 regno = REGNO (parmreg);
4245 if (regno >= max_parm_reg)
4248 int old_max_parm_reg = max_parm_reg;
4250 /* It's slow to expand this one register at a time,
4251 but it's also rare and we need max_parm_reg to be
4252 precisely correct. */
4253 max_parm_reg = regno + 1;
4254 new = (rtx *) savealloc (max_parm_reg * sizeof (rtx));
4255 bcopy ((char *) parm_reg_stack_loc, (char *) new,
4256 old_max_parm_reg * sizeof (rtx));
4257 bzero ((char *) (new + old_max_parm_reg),
4258 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4259 parm_reg_stack_loc = new;
4262 if (GET_CODE (parmreg) == CONCAT)
4264 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
4266 regnor = REGNO (gen_realpart (submode, parmreg));
4267 regnoi = REGNO (gen_imagpart (submode, parmreg));
4269 if (stack_parm != 0)
4271 parm_reg_stack_loc[regnor]
4272 = gen_realpart (submode, stack_parm);
4273 parm_reg_stack_loc[regnoi]
4274 = gen_imagpart (submode, stack_parm);
4278 parm_reg_stack_loc[regnor] = 0;
4279 parm_reg_stack_loc[regnoi] = 0;
4283 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
4285 /* Mark the register as eliminable if we did no conversion
4286 and it was copied from memory at a fixed offset,
4287 and the arg pointer was not copied to a pseudo-reg.
4288 If the arg pointer is a pseudo reg or the offset formed
4289 an invalid address, such memory-equivalences
4290 as we make here would screw up life analysis for it. */
4291 if (nominal_mode == passed_mode
4294 && GET_CODE (stack_parm) == MEM
4295 && stack_offset.var == 0
4296 && reg_mentioned_p (virtual_incoming_args_rtx,
4297 XEXP (stack_parm, 0)))
4299 rtx linsn = get_last_insn ();
4302 /* Mark complex types separately. */
4303 if (GET_CODE (parmreg) == CONCAT)
4304 /* Scan backwards for the set of the real and
4306 for (sinsn = linsn; sinsn != 0;
4307 sinsn = prev_nonnote_insn (sinsn))
4309 set = single_set (sinsn);
4311 && SET_DEST (set) == regno_reg_rtx [regnoi])
4313 = gen_rtx_EXPR_LIST (REG_EQUIV,
4314 parm_reg_stack_loc[regnoi],
4317 && SET_DEST (set) == regno_reg_rtx [regnor])
4319 = gen_rtx_EXPR_LIST (REG_EQUIV,
4320 parm_reg_stack_loc[regnor],
4323 else if ((set = single_set (linsn)) != 0
4324 && SET_DEST (set) == parmreg)
4326 = gen_rtx_EXPR_LIST (REG_EQUIV,
4327 stack_parm, REG_NOTES (linsn));
4330 /* For pointer data type, suggest pointer register. */
4331 if (POINTER_TYPE_P (TREE_TYPE (parm)))
4332 mark_reg_pointer (parmreg,
4333 (TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm)))
4338 /* Value must be stored in the stack slot STACK_PARM
4339 during function execution. */
4341 if (promoted_mode != nominal_mode)
4343 /* Conversion is required. */
4344 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4346 emit_move_insn (tempreg, validize_mem (entry_parm));
4348 push_to_sequence (conversion_insns);
4349 entry_parm = convert_to_mode (nominal_mode, tempreg,
4350 TREE_UNSIGNED (TREE_TYPE (parm)));
4353 /* ??? This may need a big-endian conversion on sparc64. */
4354 stack_parm = change_address (stack_parm, nominal_mode,
4357 conversion_insns = get_insns ();
4362 if (entry_parm != stack_parm)
4364 if (stack_parm == 0)
4367 = assign_stack_local (GET_MODE (entry_parm),
4368 GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
4369 /* If this is a memory ref that contains aggregate components,
4370 mark it as such for cse and loop optimize. */
4371 MEM_IN_STRUCT_P (stack_parm) = aggregate;
4374 if (promoted_mode != nominal_mode)
4376 push_to_sequence (conversion_insns);
4377 emit_move_insn (validize_mem (stack_parm),
4378 validize_mem (entry_parm));
4379 conversion_insns = get_insns ();
4383 emit_move_insn (validize_mem (stack_parm),
4384 validize_mem (entry_parm));
4386 if (flag_check_memory_usage)
4388 push_to_sequence (conversion_insns);
4389 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
4390 XEXP (stack_parm, 0), ptr_mode,
4391 GEN_INT (GET_MODE_SIZE (GET_MODE
4393 TYPE_MODE (sizetype),
4394 GEN_INT (MEMORY_USE_RW),
4395 TYPE_MODE (integer_type_node));
4397 conversion_insns = get_insns ();
4400 DECL_RTL (parm) = stack_parm;
4403 /* If this "parameter" was the place where we are receiving the
4404 function's incoming structure pointer, set up the result. */
4405 if (parm == function_result_decl)
4407 tree result = DECL_RESULT (fndecl);
4408 tree restype = TREE_TYPE (result);
4411 = gen_rtx_MEM (DECL_MODE (result), DECL_RTL (parm));
4413 MEM_IN_STRUCT_P (DECL_RTL (result)) = AGGREGATE_TYPE_P (restype);
4416 if (TREE_THIS_VOLATILE (parm))
4417 MEM_VOLATILE_P (DECL_RTL (parm)) = 1;
4418 if (TREE_READONLY (parm))
4419 RTX_UNCHANGING_P (DECL_RTL (parm)) = 1;
4422 /* Output all parameter conversion instructions (possibly including calls)
4423 now that all parameters have been copied out of hard registers. */
4424 emit_insns (conversion_insns);
4426 last_parm_insn = get_last_insn ();
4428 current_function_args_size = stack_args_size.constant;
4430 /* Adjust function incoming argument size for alignment and
4433 #ifdef REG_PARM_STACK_SPACE
4434 #ifndef MAYBE_REG_PARM_STACK_SPACE
4435 current_function_args_size = MAX (current_function_args_size,
4436 REG_PARM_STACK_SPACE (fndecl));
4440 #ifdef STACK_BOUNDARY
4441 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
4443 current_function_args_size
4444 = ((current_function_args_size + STACK_BYTES - 1)
4445 / STACK_BYTES) * STACK_BYTES;
4448 #ifdef ARGS_GROW_DOWNWARD
4449 current_function_arg_offset_rtx
4450 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
4451 : expand_expr (size_binop (MINUS_EXPR, stack_args_size.var,
4452 size_int (-stack_args_size.constant)),
4453 NULL_RTX, VOIDmode, EXPAND_MEMORY_USE_BAD));
4455 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
4458 /* See how many bytes, if any, of its args a function should try to pop
4461 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
4462 current_function_args_size);
4464 /* For stdarg.h function, save info about
4465 regs and stack space used by the named args. */
4468 current_function_args_info = args_so_far;
4470 /* Set the rtx used for the function return value. Put this in its
4471 own variable so any optimizers that need this information don't have
4472 to include tree.h. Do this here so it gets done when an inlined
4473 function gets output. */
4475 current_function_return_rtx = DECL_RTL (DECL_RESULT (fndecl));
4478 /* Indicate whether REGNO is an incoming argument to the current function
4479 that was promoted to a wider mode. If so, return the RTX for the
4480 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
4481 that REGNO is promoted from and whether the promotion was signed or
4484 #ifdef PROMOTE_FUNCTION_ARGS
4487 promoted_input_arg (regno, pmode, punsignedp)
4489 enum machine_mode *pmode;
4494 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
4495 arg = TREE_CHAIN (arg))
4496 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
4497 && REGNO (DECL_INCOMING_RTL (arg)) == regno
4498 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
4500 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
4501 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
4503 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
4504 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
4505 && mode != DECL_MODE (arg))
4507 *pmode = DECL_MODE (arg);
4508 *punsignedp = unsignedp;
4509 return DECL_INCOMING_RTL (arg);
4518 /* Compute the size and offset from the start of the stacked arguments for a
4519 parm passed in mode PASSED_MODE and with type TYPE.
4521 INITIAL_OFFSET_PTR points to the current offset into the stacked
4524 The starting offset and size for this parm are returned in *OFFSET_PTR
4525 and *ARG_SIZE_PTR, respectively.
4527 IN_REGS is non-zero if the argument will be passed in registers. It will
4528 never be set if REG_PARM_STACK_SPACE is not defined.
4530 FNDECL is the function in which the argument was defined.
4532 There are two types of rounding that are done. The first, controlled by
4533 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
4534 list to be aligned to the specific boundary (in bits). This rounding
4535 affects the initial and starting offsets, but not the argument size.
4537 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
4538 optionally rounds the size of the parm to PARM_BOUNDARY. The
4539 initial offset is not affected by this rounding, while the size always
4540 is and the starting offset may be. */
4542 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
4543 initial_offset_ptr is positive because locate_and_pad_parm's
4544 callers pass in the total size of args so far as
4545 initial_offset_ptr. arg_size_ptr is always positive.*/
4548 locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
4549 initial_offset_ptr, offset_ptr, arg_size_ptr)
4550 enum machine_mode passed_mode;
4554 struct args_size *initial_offset_ptr;
4555 struct args_size *offset_ptr;
4556 struct args_size *arg_size_ptr;
4559 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
4560 enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
4561 int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
4563 #ifdef REG_PARM_STACK_SPACE
4564 /* If we have found a stack parm before we reach the end of the
4565 area reserved for registers, skip that area. */
4568 int reg_parm_stack_space = 0;
4570 #ifdef MAYBE_REG_PARM_STACK_SPACE
4571 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
4573 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
4575 if (reg_parm_stack_space > 0)
4577 if (initial_offset_ptr->var)
4579 initial_offset_ptr->var
4580 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
4581 size_int (reg_parm_stack_space));
4582 initial_offset_ptr->constant = 0;
4584 else if (initial_offset_ptr->constant < reg_parm_stack_space)
4585 initial_offset_ptr->constant = reg_parm_stack_space;
4588 #endif /* REG_PARM_STACK_SPACE */
4590 arg_size_ptr->var = 0;
4591 arg_size_ptr->constant = 0;
4593 #ifdef ARGS_GROW_DOWNWARD
4594 if (initial_offset_ptr->var)
4596 offset_ptr->constant = 0;
4597 offset_ptr->var = size_binop (MINUS_EXPR, integer_zero_node,
4598 initial_offset_ptr->var);
4602 offset_ptr->constant = - initial_offset_ptr->constant;
4603 offset_ptr->var = 0;
4605 if (where_pad != none
4606 && (TREE_CODE (sizetree) != INTEGER_CST
4607 || ((TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)))
4608 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
4609 SUB_PARM_SIZE (*offset_ptr, sizetree);
4610 if (where_pad != downward)
4611 pad_to_arg_alignment (offset_ptr, boundary);
4612 if (initial_offset_ptr->var)
4614 arg_size_ptr->var = size_binop (MINUS_EXPR,
4615 size_binop (MINUS_EXPR,
4617 initial_offset_ptr->var),
4622 arg_size_ptr->constant = (- initial_offset_ptr->constant
4623 - offset_ptr->constant);
4625 #else /* !ARGS_GROW_DOWNWARD */
4626 pad_to_arg_alignment (initial_offset_ptr, boundary);
4627 *offset_ptr = *initial_offset_ptr;
4629 #ifdef PUSH_ROUNDING
4630 if (passed_mode != BLKmode)
4631 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
4634 /* Pad_below needs the pre-rounded size to know how much to pad below
4635 so this must be done before rounding up. */
4636 if (where_pad == downward
4637 /* However, BLKmode args passed in regs have their padding done elsewhere.
4638 The stack slot must be able to hold the entire register. */
4639 && !(in_regs && passed_mode == BLKmode))
4640 pad_below (offset_ptr, passed_mode, sizetree);
4642 if (where_pad != none
4643 && (TREE_CODE (sizetree) != INTEGER_CST
4644 || ((TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)))
4645 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
4647 ADD_PARM_SIZE (*arg_size_ptr, sizetree);
4648 #endif /* ARGS_GROW_DOWNWARD */
4651 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
4652 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
4655 pad_to_arg_alignment (offset_ptr, boundary)
4656 struct args_size *offset_ptr;
4659 int boundary_in_bytes = boundary / BITS_PER_UNIT;
4661 if (boundary > BITS_PER_UNIT)
4663 if (offset_ptr->var)
4666 #ifdef ARGS_GROW_DOWNWARD
4671 (ARGS_SIZE_TREE (*offset_ptr),
4672 boundary / BITS_PER_UNIT);
4673 offset_ptr->constant = 0; /*?*/
4676 offset_ptr->constant =
4677 #ifdef ARGS_GROW_DOWNWARD
4678 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
4680 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
4685 #ifndef ARGS_GROW_DOWNWARD
4687 pad_below (offset_ptr, passed_mode, sizetree)
4688 struct args_size *offset_ptr;
4689 enum machine_mode passed_mode;
4692 if (passed_mode != BLKmode)
4694 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
4695 offset_ptr->constant
4696 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
4697 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
4698 - GET_MODE_SIZE (passed_mode));
4702 if (TREE_CODE (sizetree) != INTEGER_CST
4703 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
4705 /* Round the size up to multiple of PARM_BOUNDARY bits. */
4706 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
4708 ADD_PARM_SIZE (*offset_ptr, s2);
4709 SUB_PARM_SIZE (*offset_ptr, sizetree);
4716 round_down (value, divisor)
4720 return size_binop (MULT_EXPR,
4721 size_binop (FLOOR_DIV_EXPR, value, size_int (divisor)),
4722 size_int (divisor));
4725 /* Walk the tree of blocks describing the binding levels within a function
4726 and warn about uninitialized variables.
4727 This is done after calling flow_analysis and before global_alloc
4728 clobbers the pseudo-regs to hard regs. */
4731 uninitialized_vars_warning (block)
4734 register tree decl, sub;
4735 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
4737 if (TREE_CODE (decl) == VAR_DECL
4738 /* These warnings are unreliable for and aggregates
4739 because assigning the fields one by one can fail to convince
4740 flow.c that the entire aggregate was initialized.
4741 Unions are troublesome because members may be shorter. */
4742 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
4743 && DECL_RTL (decl) != 0
4744 && GET_CODE (DECL_RTL (decl)) == REG
4745 && regno_uninitialized (REGNO (DECL_RTL (decl))))
4746 warning_with_decl (decl,
4747 "`%s' might be used uninitialized in this function");
4748 if (TREE_CODE (decl) == VAR_DECL
4749 && DECL_RTL (decl) != 0
4750 && GET_CODE (DECL_RTL (decl)) == REG
4751 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
4752 warning_with_decl (decl,
4753 "variable `%s' might be clobbered by `longjmp' or `vfork'");
4755 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
4756 uninitialized_vars_warning (sub);
4759 /* Do the appropriate part of uninitialized_vars_warning
4760 but for arguments instead of local variables. */
4763 setjmp_args_warning ()
4766 for (decl = DECL_ARGUMENTS (current_function_decl);
4767 decl; decl = TREE_CHAIN (decl))
4768 if (DECL_RTL (decl) != 0
4769 && GET_CODE (DECL_RTL (decl)) == REG
4770 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
4771 warning_with_decl (decl, "argument `%s' might be clobbered by `longjmp' or `vfork'");
4774 /* If this function call setjmp, put all vars into the stack
4775 unless they were declared `register'. */
4778 setjmp_protect (block)
4781 register tree decl, sub;
4782 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
4783 if ((TREE_CODE (decl) == VAR_DECL
4784 || TREE_CODE (decl) == PARM_DECL)
4785 && DECL_RTL (decl) != 0
4786 && (GET_CODE (DECL_RTL (decl)) == REG
4787 || (GET_CODE (DECL_RTL (decl)) == MEM
4788 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
4789 /* If this variable came from an inline function, it must be
4790 that it's life doesn't overlap the setjmp. If there was a
4791 setjmp in the function, it would already be in memory. We
4792 must exclude such variable because their DECL_RTL might be
4793 set to strange things such as virtual_stack_vars_rtx. */
4794 && ! DECL_FROM_INLINE (decl)
4796 #ifdef NON_SAVING_SETJMP
4797 /* If longjmp doesn't restore the registers,
4798 don't put anything in them. */
4802 ! DECL_REGISTER (decl)))
4803 put_var_into_stack (decl);
4804 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
4805 setjmp_protect (sub);
4808 /* Like the previous function, but for args instead of local variables. */
4811 setjmp_protect_args ()
4814 for (decl = DECL_ARGUMENTS (current_function_decl);
4815 decl; decl = TREE_CHAIN (decl))
4816 if ((TREE_CODE (decl) == VAR_DECL
4817 || TREE_CODE (decl) == PARM_DECL)
4818 && DECL_RTL (decl) != 0
4819 && (GET_CODE (DECL_RTL (decl)) == REG
4820 || (GET_CODE (DECL_RTL (decl)) == MEM
4821 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
4823 /* If longjmp doesn't restore the registers,
4824 don't put anything in them. */
4825 #ifdef NON_SAVING_SETJMP
4829 ! DECL_REGISTER (decl)))
4830 put_var_into_stack (decl);
4833 /* Return the context-pointer register corresponding to DECL,
4834 or 0 if it does not need one. */
4837 lookup_static_chain (decl)
4840 tree context = decl_function_context (decl);
4844 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
4847 /* We treat inline_function_decl as an alias for the current function
4848 because that is the inline function whose vars, types, etc.
4849 are being merged into the current function.
4850 See expand_inline_function. */
4851 if (context == current_function_decl || context == inline_function_decl)
4852 return virtual_stack_vars_rtx;
4854 for (link = context_display; link; link = TREE_CHAIN (link))
4855 if (TREE_PURPOSE (link) == context)
4856 return RTL_EXPR_RTL (TREE_VALUE (link));
4861 /* Convert a stack slot address ADDR for variable VAR
4862 (from a containing function)
4863 into an address valid in this function (using a static chain). */
4866 fix_lexical_addr (addr, var)
4871 HOST_WIDE_INT displacement;
4872 tree context = decl_function_context (var);
4873 struct function *fp;
4876 /* If this is the present function, we need not do anything. */
4877 if (context == current_function_decl || context == inline_function_decl)
4880 for (fp = outer_function_chain; fp; fp = fp->next)
4881 if (fp->decl == context)
4887 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
4888 addr = XEXP (XEXP (addr, 0), 0);
4890 /* Decode given address as base reg plus displacement. */
4891 if (GET_CODE (addr) == REG)
4892 basereg = addr, displacement = 0;
4893 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
4894 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
4898 /* We accept vars reached via the containing function's
4899 incoming arg pointer and via its stack variables pointer. */
4900 if (basereg == fp->internal_arg_pointer)
4902 /* If reached via arg pointer, get the arg pointer value
4903 out of that function's stack frame.
4905 There are two cases: If a separate ap is needed, allocate a
4906 slot in the outer function for it and dereference it that way.
4907 This is correct even if the real ap is actually a pseudo.
4908 Otherwise, just adjust the offset from the frame pointer to
4911 #ifdef NEED_SEPARATE_AP
4914 if (fp->arg_pointer_save_area == 0)
4915 fp->arg_pointer_save_area
4916 = assign_outer_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0, fp);
4918 addr = fix_lexical_addr (XEXP (fp->arg_pointer_save_area, 0), var);
4919 addr = memory_address (Pmode, addr);
4921 base = copy_to_reg (gen_rtx_MEM (Pmode, addr));
4923 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
4924 base = lookup_static_chain (var);
4928 else if (basereg == virtual_stack_vars_rtx)
4930 /* This is the same code as lookup_static_chain, duplicated here to
4931 avoid an extra call to decl_function_context. */
4934 for (link = context_display; link; link = TREE_CHAIN (link))
4935 if (TREE_PURPOSE (link) == context)
4937 base = RTL_EXPR_RTL (TREE_VALUE (link));
4945 /* Use same offset, relative to appropriate static chain or argument
4947 return plus_constant (base, displacement);
4950 /* Return the address of the trampoline for entering nested fn FUNCTION.
4951 If necessary, allocate a trampoline (in the stack frame)
4952 and emit rtl to initialize its contents (at entry to this function). */
4955 trampoline_address (function)
4961 struct function *fp;
4964 /* Find an existing trampoline and return it. */
4965 for (link = trampoline_list; link; link = TREE_CHAIN (link))
4966 if (TREE_PURPOSE (link) == function)
4968 round_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
4970 for (fp = outer_function_chain; fp; fp = fp->next)
4971 for (link = fp->trampoline_list; link; link = TREE_CHAIN (link))
4972 if (TREE_PURPOSE (link) == function)
4974 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
4976 return round_trampoline_addr (tramp);
4979 /* None exists; we must make one. */
4981 /* Find the `struct function' for the function containing FUNCTION. */
4983 fn_context = decl_function_context (function);
4984 if (fn_context != current_function_decl
4985 && fn_context != inline_function_decl)
4986 for (fp = outer_function_chain; fp; fp = fp->next)
4987 if (fp->decl == fn_context)
4990 /* Allocate run-time space for this trampoline
4991 (usually in the defining function's stack frame). */
4992 #ifdef ALLOCATE_TRAMPOLINE
4993 tramp = ALLOCATE_TRAMPOLINE (fp);
4995 /* If rounding needed, allocate extra space
4996 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
4997 #ifdef TRAMPOLINE_ALIGNMENT
4998 #define TRAMPOLINE_REAL_SIZE \
4999 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5001 #define TRAMPOLINE_REAL_SIZE (TRAMPOLINE_SIZE)
5004 tramp = assign_outer_stack_local (BLKmode, TRAMPOLINE_REAL_SIZE, 0, fp);
5006 tramp = assign_stack_local (BLKmode, TRAMPOLINE_REAL_SIZE, 0);
5009 /* Record the trampoline for reuse and note it for later initialization
5010 by expand_function_end. */
5013 push_obstacks (fp->function_maybepermanent_obstack,
5014 fp->function_maybepermanent_obstack);
5015 rtlexp = make_node (RTL_EXPR);
5016 RTL_EXPR_RTL (rtlexp) = tramp;
5017 fp->trampoline_list = tree_cons (function, rtlexp, fp->trampoline_list);
5022 /* Make the RTL_EXPR node temporary, not momentary, so that the
5023 trampoline_list doesn't become garbage. */
5024 int momentary = suspend_momentary ();
5025 rtlexp = make_node (RTL_EXPR);
5026 resume_momentary (momentary);
5028 RTL_EXPR_RTL (rtlexp) = tramp;
5029 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5032 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5033 return round_trampoline_addr (tramp);
5036 /* Given a trampoline address,
5037 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5040 round_trampoline_addr (tramp)
5043 #ifdef TRAMPOLINE_ALIGNMENT
5044 /* Round address up to desired boundary. */
5045 rtx temp = gen_reg_rtx (Pmode);
5046 temp = expand_binop (Pmode, add_optab, tramp,
5047 GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1),
5048 temp, 0, OPTAB_LIB_WIDEN);
5049 tramp = expand_binop (Pmode, and_optab, temp,
5050 GEN_INT (- TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT),
5051 temp, 0, OPTAB_LIB_WIDEN);
5056 /* The functions identify_blocks and reorder_blocks provide a way to
5057 reorder the tree of BLOCK nodes, for optimizers that reshuffle or
5058 duplicate portions of the RTL code. Call identify_blocks before
5059 changing the RTL, and call reorder_blocks after. */
5061 /* Put all this function's BLOCK nodes including those that are chained
5062 onto the first block into a vector, and return it.
5063 Also store in each NOTE for the beginning or end of a block
5064 the index of that block in the vector.
5065 The arguments are BLOCK, the chain of top-level blocks of the function,
5066 and INSNS, the insn chain of the function. */
5069 identify_blocks (block, insns)
5077 int next_block_number = 1;
5078 int current_block_number = 1;
5084 n_blocks = all_blocks (block, 0);
5085 block_vector = (tree *) xmalloc (n_blocks * sizeof (tree));
5086 block_stack = (int *) alloca (n_blocks * sizeof (int));
5088 all_blocks (block, block_vector);
5090 for (insn = insns; insn; insn = NEXT_INSN (insn))
5091 if (GET_CODE (insn) == NOTE)
5093 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5095 block_stack[depth++] = current_block_number;
5096 current_block_number = next_block_number;
5097 NOTE_BLOCK_NUMBER (insn) = next_block_number++;
5099 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5101 current_block_number = block_stack[--depth];
5102 NOTE_BLOCK_NUMBER (insn) = current_block_number;
5106 if (n_blocks != next_block_number)
5109 return block_vector;
5112 /* Given BLOCK_VECTOR which was returned by identify_blocks,
5113 and a revised instruction chain, rebuild the tree structure
5114 of BLOCK nodes to correspond to the new order of RTL.
5115 The new block tree is inserted below TOP_BLOCK.
5116 Returns the current top-level block. */
5119 reorder_blocks (block_vector, block, insns)
5124 tree current_block = block;
5127 if (block_vector == 0)
5130 /* Prune the old trees away, so that it doesn't get in the way. */
5131 BLOCK_SUBBLOCKS (current_block) = 0;
5132 BLOCK_CHAIN (current_block) = 0;
5134 for (insn = insns; insn; insn = NEXT_INSN (insn))
5135 if (GET_CODE (insn) == NOTE)
5137 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5139 tree block = block_vector[NOTE_BLOCK_NUMBER (insn)];
5140 /* If we have seen this block before, copy it. */
5141 if (TREE_ASM_WRITTEN (block))
5142 block = copy_node (block);
5143 BLOCK_SUBBLOCKS (block) = 0;
5144 TREE_ASM_WRITTEN (block) = 1;
5145 BLOCK_SUPERCONTEXT (block) = current_block;
5146 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
5147 BLOCK_SUBBLOCKS (current_block) = block;
5148 current_block = block;
5149 NOTE_SOURCE_FILE (insn) = 0;
5151 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5153 BLOCK_SUBBLOCKS (current_block)
5154 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5155 current_block = BLOCK_SUPERCONTEXT (current_block);
5156 NOTE_SOURCE_FILE (insn) = 0;
5160 BLOCK_SUBBLOCKS (current_block)
5161 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5162 return current_block;
5165 /* Reverse the order of elements in the chain T of blocks,
5166 and return the new head of the chain (old last element). */
5172 register tree prev = 0, decl, next;
5173 for (decl = t; decl; decl = next)
5175 next = BLOCK_CHAIN (decl);
5176 BLOCK_CHAIN (decl) = prev;
5182 /* Count the subblocks of the list starting with BLOCK, and list them
5183 all into the vector VECTOR. Also clear TREE_ASM_WRITTEN in all
5187 all_blocks (block, vector)
5195 TREE_ASM_WRITTEN (block) = 0;
5197 /* Record this block. */
5199 vector[n_blocks] = block;
5203 /* Record the subblocks, and their subblocks... */
5204 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
5205 vector ? vector + n_blocks : 0);
5206 block = BLOCK_CHAIN (block);
5212 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
5213 and initialize static variables for generating RTL for the statements
5217 init_function_start (subr, filename, line)
5222 init_stmt_for_function ();
5224 cse_not_expected = ! optimize;
5226 /* Caller save not needed yet. */
5227 caller_save_needed = 0;
5229 /* No stack slots have been made yet. */
5230 stack_slot_list = 0;
5232 /* There is no stack slot for handling nonlocal gotos. */
5233 nonlocal_goto_handler_slot = 0;
5234 nonlocal_goto_stack_level = 0;
5236 /* No labels have been declared for nonlocal use. */
5237 nonlocal_labels = 0;
5239 /* No function calls so far in this function. */
5240 function_call_count = 0;
5242 /* No parm regs have been allocated.
5243 (This is important for output_inline_function.) */
5244 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
5246 /* Initialize the RTL mechanism. */
5249 /* Initialize the queue of pending postincrement and postdecrements,
5250 and some other info in expr.c. */
5253 /* We haven't done register allocation yet. */
5256 init_const_rtx_hash_table ();
5258 current_function_name = (*decl_printable_name) (subr, 2);
5260 /* Nonzero if this is a nested function that uses a static chain. */
5262 current_function_needs_context
5263 = (decl_function_context (current_function_decl) != 0
5264 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
5266 /* Set if a call to setjmp is seen. */
5267 current_function_calls_setjmp = 0;
5269 /* Set if a call to longjmp is seen. */
5270 current_function_calls_longjmp = 0;
5272 current_function_calls_alloca = 0;
5273 current_function_has_nonlocal_label = 0;
5274 current_function_has_nonlocal_goto = 0;
5275 current_function_contains_functions = 0;
5276 current_function_is_thunk = 0;
5278 current_function_returns_pcc_struct = 0;
5279 current_function_returns_struct = 0;
5280 current_function_epilogue_delay_list = 0;
5281 current_function_uses_const_pool = 0;
5282 current_function_uses_pic_offset_table = 0;
5284 /* We have not yet needed to make a label to jump to for tail-recursion. */
5285 tail_recursion_label = 0;
5287 /* We haven't had a need to make a save area for ap yet. */
5289 arg_pointer_save_area = 0;
5291 /* No stack slots allocated yet. */
5294 /* No SAVE_EXPRs in this function yet. */
5297 /* No RTL_EXPRs in this function yet. */
5300 /* Set up to allocate temporaries. */
5303 /* Within function body, compute a type's size as soon it is laid out. */
5304 immediate_size_expand++;
5306 /* We haven't made any trampolines for this function yet. */
5307 trampoline_list = 0;
5309 init_pending_stack_adjust ();
5310 inhibit_defer_pop = 0;
5312 current_function_outgoing_args_size = 0;
5314 /* Prevent ever trying to delete the first instruction of a function.
5315 Also tell final how to output a linenum before the function prologue. */
5316 emit_line_note (filename, line);
5318 /* Make sure first insn is a note even if we don't want linenums.
5319 This makes sure the first insn will never be deleted.
5320 Also, final expects a note to appear there. */
5321 emit_note (NULL_PTR, NOTE_INSN_DELETED);
5323 /* Set flags used by final.c. */
5324 if (aggregate_value_p (DECL_RESULT (subr)))
5326 #ifdef PCC_STATIC_STRUCT_RETURN
5327 current_function_returns_pcc_struct = 1;
5329 current_function_returns_struct = 1;
5332 /* Warn if this value is an aggregate type,
5333 regardless of which calling convention we are using for it. */
5334 if (warn_aggregate_return
5335 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
5336 warning ("function returns an aggregate");
5338 current_function_returns_pointer
5339 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
5341 /* Indicate that we need to distinguish between the return value of the
5342 present function and the return value of a function being called. */
5343 rtx_equal_function_value_matters = 1;
5345 /* Indicate that we have not instantiated virtual registers yet. */
5346 virtuals_instantiated = 0;
5348 /* Indicate we have no need of a frame pointer yet. */
5349 frame_pointer_needed = 0;
5351 /* By default assume not varargs or stdarg. */
5352 current_function_varargs = 0;
5353 current_function_stdarg = 0;
5356 /* Indicate that the current function uses extra args
5357 not explicitly mentioned in the argument list in any fashion. */
5362 current_function_varargs = 1;
5365 /* Expand a call to __main at the beginning of a possible main function. */
5367 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
5368 #undef HAS_INIT_SECTION
5369 #define HAS_INIT_SECTION
5373 expand_main_function ()
5375 #if !defined (HAS_INIT_SECTION)
5376 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, NAME__MAIN), 0,
5378 #endif /* not HAS_INIT_SECTION */
5381 extern struct obstack permanent_obstack;
5383 /* Start the RTL for a new function, and set variables used for
5385 SUBR is the FUNCTION_DECL node.
5386 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
5387 the function's parameters, which must be run at any return statement. */
5390 expand_function_start (subr, parms_have_cleanups)
5392 int parms_have_cleanups;
5396 rtx last_ptr = NULL_RTX;
5398 /* Make sure volatile mem refs aren't considered
5399 valid operands of arithmetic insns. */
5400 init_recog_no_volatile ();
5402 /* If function gets a static chain arg, store it in the stack frame.
5403 Do this first, so it gets the first stack slot offset. */
5404 if (current_function_needs_context)
5406 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
5408 /* Delay copying static chain if it is not a register to avoid
5409 conflicts with regs used for parameters. */
5410 if (! SMALL_REGISTER_CLASSES
5411 || GET_CODE (static_chain_incoming_rtx) == REG)
5412 emit_move_insn (last_ptr, static_chain_incoming_rtx);
5415 /* If the parameters of this function need cleaning up, get a label
5416 for the beginning of the code which executes those cleanups. This must
5417 be done before doing anything with return_label. */
5418 if (parms_have_cleanups)
5419 cleanup_label = gen_label_rtx ();
5423 /* Make the label for return statements to jump to, if this machine
5424 does not have a one-instruction return and uses an epilogue,
5425 or if it returns a structure, or if it has parm cleanups. */
5427 if (cleanup_label == 0 && HAVE_return
5428 && ! current_function_returns_pcc_struct
5429 && ! (current_function_returns_struct && ! optimize))
5432 return_label = gen_label_rtx ();
5434 return_label = gen_label_rtx ();
5437 /* Initialize rtx used to return the value. */
5438 /* Do this before assign_parms so that we copy the struct value address
5439 before any library calls that assign parms might generate. */
5441 /* Decide whether to return the value in memory or in a register. */
5442 if (aggregate_value_p (DECL_RESULT (subr)))
5444 /* Returning something that won't go in a register. */
5445 register rtx value_address = 0;
5447 #ifdef PCC_STATIC_STRUCT_RETURN
5448 if (current_function_returns_pcc_struct)
5450 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
5451 value_address = assemble_static_space (size);
5456 /* Expect to be passed the address of a place to store the value.
5457 If it is passed as an argument, assign_parms will take care of
5459 if (struct_value_incoming_rtx)
5461 value_address = gen_reg_rtx (Pmode);
5462 emit_move_insn (value_address, struct_value_incoming_rtx);
5467 DECL_RTL (DECL_RESULT (subr))
5468 = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
5469 MEM_IN_STRUCT_P (DECL_RTL (DECL_RESULT (subr)))
5470 = AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
5473 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
5474 /* If return mode is void, this decl rtl should not be used. */
5475 DECL_RTL (DECL_RESULT (subr)) = 0;
5476 else if (parms_have_cleanups)
5478 /* If function will end with cleanup code for parms,
5479 compute the return values into a pseudo reg,
5480 which we will copy into the true return register
5481 after the cleanups are done. */
5483 enum machine_mode mode = DECL_MODE (DECL_RESULT (subr));
5485 #ifdef PROMOTE_FUNCTION_RETURN
5486 tree type = TREE_TYPE (DECL_RESULT (subr));
5487 int unsignedp = TREE_UNSIGNED (type);
5489 mode = promote_mode (type, mode, &unsignedp, 1);
5492 DECL_RTL (DECL_RESULT (subr)) = gen_reg_rtx (mode);
5495 /* Scalar, returned in a register. */
5497 #ifdef FUNCTION_OUTGOING_VALUE
5498 DECL_RTL (DECL_RESULT (subr))
5499 = FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (subr)), subr);
5501 DECL_RTL (DECL_RESULT (subr))
5502 = FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (subr)), subr);
5505 /* Mark this reg as the function's return value. */
5506 if (GET_CODE (DECL_RTL (DECL_RESULT (subr))) == REG)
5508 REG_FUNCTION_VALUE_P (DECL_RTL (DECL_RESULT (subr))) = 1;
5509 /* Needed because we may need to move this to memory
5510 in case it's a named return value whose address is taken. */
5511 DECL_REGISTER (DECL_RESULT (subr)) = 1;
5515 /* Initialize rtx for parameters and local variables.
5516 In some cases this requires emitting insns. */
5518 assign_parms (subr, 0);
5520 /* Copy the static chain now if it wasn't a register. The delay is to
5521 avoid conflicts with the parameter passing registers. */
5523 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
5524 if (GET_CODE (static_chain_incoming_rtx) != REG)
5525 emit_move_insn (last_ptr, static_chain_incoming_rtx);
5527 /* The following was moved from init_function_start.
5528 The move is supposed to make sdb output more accurate. */
5529 /* Indicate the beginning of the function body,
5530 as opposed to parm setup. */
5531 emit_note (NULL_PTR, NOTE_INSN_FUNCTION_BEG);
5533 /* If doing stupid allocation, mark parms as born here. */
5535 if (GET_CODE (get_last_insn ()) != NOTE)
5536 emit_note (NULL_PTR, NOTE_INSN_DELETED);
5537 parm_birth_insn = get_last_insn ();
5541 for (i = LAST_VIRTUAL_REGISTER + 1; i < max_parm_reg; i++)
5542 use_variable (regno_reg_rtx[i]);
5544 if (current_function_internal_arg_pointer != virtual_incoming_args_rtx)
5545 use_variable (current_function_internal_arg_pointer);
5548 context_display = 0;
5549 if (current_function_needs_context)
5551 /* Fetch static chain values for containing functions. */
5552 tem = decl_function_context (current_function_decl);
5553 /* If not doing stupid register allocation copy the static chain
5554 pointer into a pseudo. If we have small register classes, copy
5555 the value from memory if static_chain_incoming_rtx is a REG. If
5556 we do stupid register allocation, we use the stack address
5558 if (tem && ! obey_regdecls)
5560 /* If the static chain originally came in a register, put it back
5561 there, then move it out in the next insn. The reason for
5562 this peculiar code is to satisfy function integration. */
5563 if (SMALL_REGISTER_CLASSES
5564 && GET_CODE (static_chain_incoming_rtx) == REG)
5565 emit_move_insn (static_chain_incoming_rtx, last_ptr);
5566 last_ptr = copy_to_reg (static_chain_incoming_rtx);
5571 tree rtlexp = make_node (RTL_EXPR);
5573 RTL_EXPR_RTL (rtlexp) = last_ptr;
5574 context_display = tree_cons (tem, rtlexp, context_display);
5575 tem = decl_function_context (tem);
5578 /* Chain thru stack frames, assuming pointer to next lexical frame
5579 is found at the place we always store it. */
5580 #ifdef FRAME_GROWS_DOWNWARD
5581 last_ptr = plus_constant (last_ptr, - GET_MODE_SIZE (Pmode));
5583 last_ptr = copy_to_reg (gen_rtx_MEM (Pmode,
5584 memory_address (Pmode, last_ptr)));
5586 /* If we are not optimizing, ensure that we know that this
5587 piece of context is live over the entire function. */
5589 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
5594 /* After the display initializations is where the tail-recursion label
5595 should go, if we end up needing one. Ensure we have a NOTE here
5596 since some things (like trampolines) get placed before this. */
5597 tail_recursion_reentry = emit_note (NULL_PTR, NOTE_INSN_DELETED);
5599 /* Evaluate now the sizes of any types declared among the arguments. */
5600 for (tem = nreverse (get_pending_sizes ()); tem; tem = TREE_CHAIN (tem))
5602 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode,
5603 EXPAND_MEMORY_USE_BAD);
5604 /* Flush the queue in case this parameter declaration has
5609 /* Make sure there is a line number after the function entry setup code. */
5610 force_next_line_note ();
5613 /* Generate RTL for the end of the current function.
5614 FILENAME and LINE are the current position in the source file.
5616 It is up to language-specific callers to do cleanups for parameters--
5617 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
5620 expand_function_end (filename, line, end_bindings)
5628 #ifdef TRAMPOLINE_TEMPLATE
5629 static rtx initial_trampoline;
5632 #ifdef NON_SAVING_SETJMP
5633 /* Don't put any variables in registers if we call setjmp
5634 on a machine that fails to restore the registers. */
5635 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
5637 if (DECL_INITIAL (current_function_decl) != error_mark_node)
5638 setjmp_protect (DECL_INITIAL (current_function_decl));
5640 setjmp_protect_args ();
5644 /* Save the argument pointer if a save area was made for it. */
5645 if (arg_pointer_save_area)
5647 rtx x = gen_move_insn (arg_pointer_save_area, virtual_incoming_args_rtx);
5648 emit_insn_before (x, tail_recursion_reentry);
5651 /* Initialize any trampolines required by this function. */
5652 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5654 tree function = TREE_PURPOSE (link);
5655 rtx context = lookup_static_chain (function);
5656 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
5660 #ifdef TRAMPOLINE_TEMPLATE
5661 /* First make sure this compilation has a template for
5662 initializing trampolines. */
5663 if (initial_trampoline == 0)
5665 end_temporary_allocation ();
5667 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
5668 resume_temporary_allocation ();
5672 /* Generate insns to initialize the trampoline. */
5674 tramp = round_trampoline_addr (XEXP (tramp, 0));
5675 #ifdef TRAMPOLINE_TEMPLATE
5676 blktramp = change_address (initial_trampoline, BLKmode, tramp);
5677 emit_block_move (blktramp, initial_trampoline,
5678 GEN_INT (TRAMPOLINE_SIZE),
5679 TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
5681 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
5685 /* Put those insns at entry to the containing function (this one). */
5686 emit_insns_before (seq, tail_recursion_reentry);
5689 /* If we are doing stack checking and this function makes calls,
5690 do a stack probe at the start of the function to ensure we have enough
5691 space for another stack frame. */
5692 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
5696 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
5697 if (GET_CODE (insn) == CALL_INSN)
5700 probe_stack_range (STACK_CHECK_PROTECT,
5701 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
5704 emit_insns_before (seq, tail_recursion_reentry);
5709 /* Warn about unused parms if extra warnings were specified. */
5710 if (warn_unused && extra_warnings)
5714 for (decl = DECL_ARGUMENTS (current_function_decl);
5715 decl; decl = TREE_CHAIN (decl))
5716 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
5717 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
5718 warning_with_decl (decl, "unused parameter `%s'");
5721 /* Delete handlers for nonlocal gotos if nothing uses them. */
5722 if (nonlocal_goto_handler_slot != 0 && !current_function_has_nonlocal_label)
5725 /* End any sequences that failed to be closed due to syntax errors. */
5726 while (in_sequence_p ())
5729 /* Outside function body, can't compute type's actual size
5730 until next function's body starts. */
5731 immediate_size_expand--;
5733 /* If doing stupid register allocation,
5734 mark register parms as dying here. */
5739 for (i = LAST_VIRTUAL_REGISTER + 1; i < max_parm_reg; i++)
5740 use_variable (regno_reg_rtx[i]);
5742 /* Likewise for the regs of all the SAVE_EXPRs in the function. */
5744 for (tem = save_expr_regs; tem; tem = XEXP (tem, 1))
5746 use_variable (XEXP (tem, 0));
5747 use_variable_after (XEXP (tem, 0), parm_birth_insn);
5750 if (current_function_internal_arg_pointer != virtual_incoming_args_rtx)
5751 use_variable (current_function_internal_arg_pointer);
5754 clear_pending_stack_adjust ();
5755 do_pending_stack_adjust ();
5757 /* Mark the end of the function body.
5758 If control reaches this insn, the function can drop through
5759 without returning a value. */
5760 emit_note (NULL_PTR, NOTE_INSN_FUNCTION_END);
5762 /* Must mark the last line number note in the function, so that the test
5763 coverage code can avoid counting the last line twice. This just tells
5764 the code to ignore the immediately following line note, since there
5765 already exists a copy of this note somewhere above. This line number
5766 note is still needed for debugging though, so we can't delete it. */
5767 if (flag_test_coverage)
5768 emit_note (NULL_PTR, NOTE_REPEATED_LINE_NUMBER);
5770 /* Output a linenumber for the end of the function.
5771 SDB depends on this. */
5772 emit_line_note_force (filename, line);
5774 /* Output the label for the actual return from the function,
5775 if one is expected. This happens either because a function epilogue
5776 is used instead of a return instruction, or because a return was done
5777 with a goto in order to run local cleanups, or because of pcc-style
5778 structure returning. */
5781 emit_label (return_label);
5783 /* C++ uses this. */
5785 expand_end_bindings (0, 0, 0);
5787 /* Now handle any leftover exception regions that may have been
5788 created for the parameters. */
5790 rtx last = get_last_insn ();
5793 expand_leftover_cleanups ();
5795 /* If the above emitted any code, may sure we jump around it. */
5796 if (last != get_last_insn ())
5798 label = gen_label_rtx ();
5799 last = emit_jump_insn_after (gen_jump (label), last);
5800 last = emit_barrier_after (last);
5805 /* If we had calls to alloca, and this machine needs
5806 an accurate stack pointer to exit the function,
5807 insert some code to save and restore the stack pointer. */
5808 #ifdef EXIT_IGNORE_STACK
5809 if (! EXIT_IGNORE_STACK)
5811 if (current_function_calls_alloca)
5815 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
5816 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
5819 /* If scalar return value was computed in a pseudo-reg,
5820 copy that to the hard return register. */
5821 if (DECL_RTL (DECL_RESULT (current_function_decl)) != 0
5822 && GET_CODE (DECL_RTL (DECL_RESULT (current_function_decl))) == REG
5823 && (REGNO (DECL_RTL (DECL_RESULT (current_function_decl)))
5824 >= FIRST_PSEUDO_REGISTER))
5826 rtx real_decl_result;
5828 #ifdef FUNCTION_OUTGOING_VALUE
5830 = FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl)),
5831 current_function_decl);
5834 = FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl)),
5835 current_function_decl);
5837 REG_FUNCTION_VALUE_P (real_decl_result) = 1;
5838 /* If this is a BLKmode structure being returned in registers, then use
5839 the mode computed in expand_return. */
5840 if (GET_MODE (real_decl_result) == BLKmode)
5841 PUT_MODE (real_decl_result,
5842 GET_MODE (DECL_RTL (DECL_RESULT (current_function_decl))));
5843 emit_move_insn (real_decl_result,
5844 DECL_RTL (DECL_RESULT (current_function_decl)));
5845 emit_insn (gen_rtx_USE (VOIDmode, real_decl_result));
5847 /* The delay slot scheduler assumes that current_function_return_rtx
5848 holds the hard register containing the return value, not a temporary
5850 current_function_return_rtx = real_decl_result;
5853 /* If returning a structure, arrange to return the address of the value
5854 in a place where debuggers expect to find it.
5856 If returning a structure PCC style,
5857 the caller also depends on this value.
5858 And current_function_returns_pcc_struct is not necessarily set. */
5859 if (current_function_returns_struct
5860 || current_function_returns_pcc_struct)
5862 rtx value_address = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
5863 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
5864 #ifdef FUNCTION_OUTGOING_VALUE
5866 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
5867 current_function_decl);
5870 = FUNCTION_VALUE (build_pointer_type (type),
5871 current_function_decl);
5874 /* Mark this as a function return value so integrate will delete the
5875 assignment and USE below when inlining this function. */
5876 REG_FUNCTION_VALUE_P (outgoing) = 1;
5878 emit_move_insn (outgoing, value_address);
5879 use_variable (outgoing);
5882 /* Output a return insn if we are using one.
5883 Otherwise, let the rtl chain end here, to drop through
5884 into the epilogue. */
5889 emit_jump_insn (gen_return ());
5894 /* Fix up any gotos that jumped out to the outermost
5895 binding level of the function.
5896 Must follow emitting RETURN_LABEL. */
5898 /* If you have any cleanups to do at this point,
5899 and they need to create temporary variables,
5900 then you will lose. */
5901 expand_fixups (get_insns ());
5904 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
5906 static int *prologue;
5907 static int *epilogue;
5909 /* Create an array that records the INSN_UIDs of INSNS (either a sequence
5910 or a single insn). */
5913 record_insns (insns)
5918 if (GET_CODE (insns) == SEQUENCE)
5920 int len = XVECLEN (insns, 0);
5921 vec = (int *) oballoc ((len + 1) * sizeof (int));
5924 vec[len] = INSN_UID (XVECEXP (insns, 0, len));
5928 vec = (int *) oballoc (2 * sizeof (int));
5929 vec[0] = INSN_UID (insns);
5935 /* Determine how many INSN_UIDs in VEC are part of INSN. */
5937 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
5939 contains (insn, vec)
5945 if (GET_CODE (insn) == INSN
5946 && GET_CODE (PATTERN (insn)) == SEQUENCE)
5949 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
5950 for (j = 0; vec[j]; j++)
5951 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == vec[j])
5957 for (j = 0; vec[j]; j++)
5958 if (INSN_UID (insn) == vec[j])
5963 #endif /* HAVE_prologue || HAVE_epilogue */
5965 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
5966 this into place with notes indicating where the prologue ends and where
5967 the epilogue begins. Update the basic block information when possible. */
5970 thread_prologue_and_epilogue_insns (f)
5973 #ifdef HAVE_prologue
5978 /* The first insn (a NOTE_INSN_DELETED) is followed by zero or more
5979 prologue insns and a NOTE_INSN_PROLOGUE_END. */
5980 emit_note_after (NOTE_INSN_PROLOGUE_END, f);
5981 seq = gen_prologue ();
5982 head = emit_insn_after (seq, f);
5984 /* Include the new prologue insns in the first block. Ignore them
5985 if they form a basic block unto themselves. */
5986 if (basic_block_head && n_basic_blocks
5987 && GET_CODE (basic_block_head[0]) != CODE_LABEL)
5988 basic_block_head[0] = NEXT_INSN (f);
5990 /* Retain a map of the prologue insns. */
5991 prologue = record_insns (GET_CODE (seq) == SEQUENCE ? seq : head);
5997 #ifdef HAVE_epilogue
6000 rtx insn = get_last_insn ();
6001 rtx prev = prev_nonnote_insn (insn);
6003 /* If we end with a BARRIER, we don't need an epilogue. */
6004 if (! (prev && GET_CODE (prev) == BARRIER))
6010 /* The last basic block ends with a NOTE_INSN_EPILOGUE_BEG, the
6011 epilogue insns, the USE insns at the end of a function,
6012 the jump insn that returns, and then a BARRIER. */
6014 /* Move the USE insns at the end of a function onto a list. */
6016 && GET_CODE (prev) == INSN
6017 && GET_CODE (PATTERN (prev)) == USE)
6020 prev = prev_nonnote_insn (prev);
6022 NEXT_INSN (PREV_INSN (tem)) = NEXT_INSN (tem);
6023 PREV_INSN (NEXT_INSN (tem)) = PREV_INSN (tem);
6026 NEXT_INSN (tem) = first_use;
6027 PREV_INSN (first_use) = tem;
6034 emit_barrier_after (insn);
6036 seq = gen_epilogue ();
6037 tail = emit_jump_insn_after (seq, insn);
6039 /* Insert the USE insns immediately before the return insn, which
6040 must be the first instruction before the final barrier. */
6043 tem = prev_nonnote_insn (get_last_insn ());
6044 NEXT_INSN (PREV_INSN (tem)) = first_use;
6045 PREV_INSN (first_use) = PREV_INSN (tem);
6046 PREV_INSN (tem) = last_use;
6047 NEXT_INSN (last_use) = tem;
6050 emit_note_after (NOTE_INSN_EPILOGUE_BEG, insn);
6052 /* Include the new epilogue insns in the last block. Ignore
6053 them if they form a basic block unto themselves. */
6054 if (basic_block_end && n_basic_blocks
6055 && GET_CODE (basic_block_end[n_basic_blocks - 1]) != JUMP_INSN)
6056 basic_block_end[n_basic_blocks - 1] = tail;
6058 /* Retain a map of the epilogue insns. */
6059 epilogue = record_insns (GET_CODE (seq) == SEQUENCE ? seq : tail);
6067 /* Reposition the prologue-end and epilogue-begin notes after instruction
6068 scheduling and delayed branch scheduling. */
6071 reposition_prologue_and_epilogue_notes (f)
6074 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
6075 /* Reposition the prologue and epilogue notes. */
6083 register rtx insn, note = 0;
6085 /* Scan from the beginning until we reach the last prologue insn.
6086 We apparently can't depend on basic_block_{head,end} after
6088 for (len = 0; prologue[len]; len++)
6090 for (insn = f; len && insn; insn = NEXT_INSN (insn))
6092 if (GET_CODE (insn) == NOTE)
6094 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
6097 else if ((len -= contains (insn, prologue)) == 0)
6099 /* Find the prologue-end note if we haven't already, and
6100 move it to just after the last prologue insn. */
6103 for (note = insn; (note = NEXT_INSN (note));)
6104 if (GET_CODE (note) == NOTE
6105 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
6108 next = NEXT_INSN (note);
6109 prev = PREV_INSN (note);
6111 NEXT_INSN (prev) = next;
6113 PREV_INSN (next) = prev;
6114 add_insn_after (note, insn);
6121 register rtx insn, note = 0;
6123 /* Scan from the end until we reach the first epilogue insn.
6124 We apparently can't depend on basic_block_{head,end} after
6126 for (len = 0; epilogue[len]; len++)
6128 for (insn = get_last_insn (); len && insn; insn = PREV_INSN (insn))
6130 if (GET_CODE (insn) == NOTE)
6132 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
6135 else if ((len -= contains (insn, epilogue)) == 0)
6137 /* Find the epilogue-begin note if we haven't already, and
6138 move it to just before the first epilogue insn. */
6141 for (note = insn; (note = PREV_INSN (note));)
6142 if (GET_CODE (note) == NOTE
6143 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
6146 next = NEXT_INSN (note);
6147 prev = PREV_INSN (note);
6149 NEXT_INSN (prev) = next;
6151 PREV_INSN (next) = prev;
6152 add_insn_after (note, PREV_INSN (insn));
6157 #endif /* HAVE_prologue or HAVE_epilogue */