1 /* Expands front end tree to back end RTL for GNU C-Compiler
2 Copyright (C) 1987, 88, 89, 91-94, 1995 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. */
49 #include "insn-flags.h"
51 #include "insn-codes.h"
53 #include "hard-reg-set.h"
54 #include "insn-config.h"
57 #include "basic-block.h"
61 /* Some systems use __main in a way incompatible with its use in gcc, in these
62 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
63 give the same symbol without quotes for an alternative entry point. You
64 must define both, or neither. */
66 #define NAME__MAIN "__main"
67 #define SYMBOL__MAIN __main
70 /* Round a value to the lowest integer less than it that is a multiple of
71 the required alignment. Avoid using division in case the value is
72 negative. Assume the alignment is a power of two. */
73 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
75 /* Similar, but round to the next highest integer that meets the
77 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
79 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
80 during rtl generation. If they are different register numbers, this is
81 always true. It may also be true if
82 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
83 generation. See fix_lexical_addr for details. */
85 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
86 #define NEED_SEPARATE_AP
89 /* Number of bytes of args popped by function being compiled on its return.
90 Zero if no bytes are to be popped.
91 May affect compilation of return insn or of function epilogue. */
93 int current_function_pops_args;
95 /* Nonzero if function being compiled needs to be given an address
96 where the value should be stored. */
98 int current_function_returns_struct;
100 /* Nonzero if function being compiled needs to
101 return the address of where it has put a structure value. */
103 int current_function_returns_pcc_struct;
105 /* Nonzero if function being compiled needs to be passed a static chain. */
107 int current_function_needs_context;
109 /* Nonzero if function being compiled can call setjmp. */
111 int current_function_calls_setjmp;
113 /* Nonzero if function being compiled can call longjmp. */
115 int current_function_calls_longjmp;
117 /* Nonzero if function being compiled receives nonlocal gotos
118 from nested functions. */
120 int current_function_has_nonlocal_label;
122 /* Nonzero if function being compiled has nonlocal gotos to parent
125 int current_function_has_nonlocal_goto;
127 /* Nonzero if function being compiled contains nested functions. */
129 int current_function_contains_functions;
131 /* Nonzero if function being compiled can call alloca,
132 either as a subroutine or builtin. */
134 int current_function_calls_alloca;
136 /* Nonzero if the current function returns a pointer type */
138 int current_function_returns_pointer;
140 /* If some insns can be deferred to the delay slots of the epilogue, the
141 delay list for them is recorded here. */
143 rtx current_function_epilogue_delay_list;
145 /* If function's args have a fixed size, this is that size, in bytes.
147 May affect compilation of return insn or of function epilogue. */
149 int current_function_args_size;
151 /* # bytes the prologue should push and pretend that the caller pushed them.
152 The prologue must do this, but only if parms can be passed in registers. */
154 int current_function_pretend_args_size;
156 /* # of bytes of outgoing arguments. If ACCUMULATE_OUTGOING_ARGS is
157 defined, the needed space is pushed by the prologue. */
159 int current_function_outgoing_args_size;
161 /* This is the offset from the arg pointer to the place where the first
162 anonymous arg can be found, if there is one. */
164 rtx current_function_arg_offset_rtx;
166 /* Nonzero if current function uses varargs.h or equivalent.
167 Zero for functions that use stdarg.h. */
169 int current_function_varargs;
171 /* Nonzero if current function uses stdarg.h or equivalent.
172 Zero for functions that use varargs.h. */
174 int current_function_stdarg;
176 /* Quantities of various kinds of registers
177 used for the current function's args. */
179 CUMULATIVE_ARGS current_function_args_info;
181 /* Name of function now being compiled. */
183 char *current_function_name;
185 /* If non-zero, an RTL expression for that location at which the current
186 function returns its result. Always equal to
187 DECL_RTL (DECL_RESULT (current_function_decl)), but provided
188 independently of the tree structures. */
190 rtx current_function_return_rtx;
192 /* Nonzero if the current function uses the constant pool. */
194 int current_function_uses_const_pool;
196 /* Nonzero if the current function uses pic_offset_table_rtx. */
197 int current_function_uses_pic_offset_table;
199 /* The arg pointer hard register, or the pseudo into which it was copied. */
200 rtx current_function_internal_arg_pointer;
202 /* The FUNCTION_DECL for an inline function currently being expanded. */
203 tree inline_function_decl;
205 /* Number of function calls seen so far in current function. */
207 int function_call_count;
209 /* List (chain of TREE_LIST) of LABEL_DECLs for all nonlocal labels
210 (labels to which there can be nonlocal gotos from nested functions)
213 tree nonlocal_labels;
215 /* RTX for stack slot that holds the current handler for nonlocal gotos.
216 Zero when function does not have nonlocal labels. */
218 rtx nonlocal_goto_handler_slot;
220 /* RTX for stack slot that holds the stack pointer value to restore
222 Zero when function does not have nonlocal labels. */
224 rtx nonlocal_goto_stack_level;
226 /* Label that will go on parm cleanup code, if any.
227 Jumping to this label runs cleanup code for parameters, if
228 such code must be run. Following this code is the logical return label. */
232 /* Label that will go on function epilogue.
233 Jumping to this label serves as a "return" instruction
234 on machines which require execution of the epilogue on all returns. */
238 /* List (chain of EXPR_LISTs) of pseudo-regs of SAVE_EXPRs.
239 So we can mark them all live at the end of the function, if nonopt. */
242 /* List (chain of EXPR_LISTs) of all stack slots in this function.
243 Made for the sake of unshare_all_rtl. */
246 /* Chain of all RTL_EXPRs that have insns in them. */
249 /* Label to jump back to for tail recursion, or 0 if we have
250 not yet needed one for this function. */
251 rtx tail_recursion_label;
253 /* Place after which to insert the tail_recursion_label if we need one. */
254 rtx tail_recursion_reentry;
256 /* Location at which to save the argument pointer if it will need to be
257 referenced. There are two cases where this is done: if nonlocal gotos
258 exist, or if vars stored at an offset from the argument pointer will be
259 needed by inner routines. */
261 rtx arg_pointer_save_area;
263 /* Offset to end of allocated area of stack frame.
264 If stack grows down, this is the address of the last stack slot allocated.
265 If stack grows up, this is the address for the next slot. */
268 /* List (chain of TREE_LISTs) of static chains for containing functions.
269 Each link has a FUNCTION_DECL in the TREE_PURPOSE and a reg rtx
270 in an RTL_EXPR in the TREE_VALUE. */
271 static tree context_display;
273 /* List (chain of TREE_LISTs) of trampolines for nested functions.
274 The trampoline sets up the static chain and jumps to the function.
275 We supply the trampoline's address when the function's address is requested.
277 Each link has a FUNCTION_DECL in the TREE_PURPOSE and a reg rtx
278 in an RTL_EXPR in the TREE_VALUE. */
279 static tree trampoline_list;
281 /* Insn after which register parms and SAVE_EXPRs are born, if nonopt. */
282 static rtx parm_birth_insn;
285 /* Nonzero if a stack slot has been generated whose address is not
286 actually valid. It means that the generated rtl must all be scanned
287 to detect and correct the invalid addresses where they occur. */
288 static int invalid_stack_slot;
291 /* Last insn of those whose job was to put parms into their nominal homes. */
292 static rtx last_parm_insn;
294 /* 1 + last pseudo register number used for loading a copy
295 of a parameter of this function. */
296 static int max_parm_reg;
298 /* Vector indexed by REGNO, containing location on stack in which
299 to put the parm which is nominally in pseudo register REGNO,
300 if we discover that that parm must go in the stack. */
301 static rtx *parm_reg_stack_loc;
303 #if 0 /* Turned off because 0 seems to work just as well. */
304 /* Cleanup lists are required for binding levels regardless of whether
305 that binding level has cleanups or not. This node serves as the
306 cleanup list whenever an empty list is required. */
307 static tree empty_cleanup_list;
310 /* Nonzero once virtual register instantiation has been done.
311 assign_stack_local uses frame_pointer_rtx when this is nonzero. */
312 static int virtuals_instantiated;
314 /* These variables hold pointers to functions to
315 save and restore machine-specific data,
316 in push_function_context and pop_function_context. */
317 void (*save_machine_status) ();
318 void (*restore_machine_status) ();
320 /* Nonzero if we need to distinguish between the return value of this function
321 and the return value of a function called by this function. This helps
324 extern int rtx_equal_function_value_matters;
325 extern tree sequence_rtl_expr;
326 extern tree bc_runtime_type_code ();
327 extern rtx bc_build_calldesc ();
328 extern char *bc_emit_trampoline ();
329 extern char *bc_end_function ();
331 /* In order to evaluate some expressions, such as function calls returning
332 structures in memory, we need to temporarily allocate stack locations.
333 We record each allocated temporary in the following structure.
335 Associated with each temporary slot is a nesting level. When we pop up
336 one level, all temporaries associated with the previous level are freed.
337 Normally, all temporaries are freed after the execution of the statement
338 in which they were created. However, if we are inside a ({...}) grouping,
339 the result may be in a temporary and hence must be preserved. If the
340 result could be in a temporary, we preserve it if we can determine which
341 one it is in. If we cannot determine which temporary may contain the
342 result, all temporaries are preserved. A temporary is preserved by
343 pretending it was allocated at the previous nesting level.
345 Automatic variables are also assigned temporary slots, at the nesting
346 level where they are defined. They are marked a "kept" so that
347 free_temp_slots will not free them. */
351 /* Points to next temporary slot. */
352 struct temp_slot *next;
353 /* The rtx to used to reference the slot. */
355 /* The rtx used to represent the address if not the address of the
356 slot above. May be an EXPR_LIST if multiple addresses exist. */
358 /* The size, in units, of the slot. */
360 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
362 /* Non-zero if this temporary is currently in use. */
364 /* Non-zero if this temporary has its address taken. */
366 /* Nesting level at which this slot is being used. */
368 /* Non-zero if this should survive a call to free_temp_slots. */
370 /* The offset of the slot from the frame_pointer, including extra space
371 for alignment. This info is for combine_temp_slots. */
373 /* The size of the slot, including extra space for alignment. This
374 info is for combine_temp_slots. */
378 /* List of all temporaries allocated, both available and in use. */
380 struct temp_slot *temp_slots;
382 /* Current nesting level for temporaries. */
386 /* The FUNCTION_DECL node for the current function. */
387 static tree this_function_decl;
389 /* Callinfo pointer for the current function. */
390 static rtx this_function_callinfo;
392 /* The label in the bytecode file of this function's actual bytecode.
394 static char *this_function_bytecode;
396 /* The call description vector for the current function. */
397 static rtx this_function_calldesc;
399 /* Size of the local variables allocated for the current function. */
402 /* Current depth of the bytecode evaluation stack. */
405 /* Maximum depth of the evaluation stack in this function. */
408 /* Current depth in statement expressions. */
409 static int stmt_expr_depth;
411 /* This structure is used to record MEMs or pseudos used to replace VAR, any
412 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
413 maintain this list in case two operands of an insn were required to match;
414 in that case we must ensure we use the same replacement. */
416 struct fixup_replacement
420 struct fixup_replacement *next;
423 /* Forward declarations. */
425 static struct temp_slot *find_temp_slot_from_address PROTO((rtx));
426 static void put_reg_into_stack PROTO((struct function *, rtx, tree,
427 enum machine_mode, enum machine_mode));
428 static void fixup_var_refs PROTO((rtx, enum machine_mode, int));
429 static struct fixup_replacement
430 *find_fixup_replacement PROTO((struct fixup_replacement **, rtx));
431 static void fixup_var_refs_insns PROTO((rtx, enum machine_mode, int,
433 static void fixup_var_refs_1 PROTO((rtx, enum machine_mode, rtx *, rtx,
434 struct fixup_replacement **));
435 static rtx fixup_memory_subreg PROTO((rtx, rtx, int));
436 static rtx walk_fixup_memory_subreg PROTO((rtx, rtx, int));
437 static rtx fixup_stack_1 PROTO((rtx, rtx));
438 static void optimize_bit_field PROTO((rtx, rtx, rtx *));
439 static void instantiate_decls PROTO((tree, int));
440 static void instantiate_decls_1 PROTO((tree, int));
441 static void instantiate_decl PROTO((rtx, int, int));
442 static int instantiate_virtual_regs_1 PROTO((rtx *, rtx, int));
443 static void delete_handlers PROTO((void));
444 static void pad_to_arg_alignment PROTO((struct args_size *, int));
445 static void pad_below PROTO((struct args_size *, enum machine_mode,
447 static tree round_down PROTO((tree, int));
448 static rtx round_trampoline_addr PROTO((rtx));
449 static tree blocks_nreverse PROTO((tree));
450 static int all_blocks PROTO((tree, tree *));
451 static int *record_insns PROTO((rtx));
452 static int contains PROTO((rtx, int *));
454 /* Pointer to chain of `struct function' for containing functions. */
455 struct function *outer_function_chain;
457 /* Given a function decl for a containing function,
458 return the `struct function' for it. */
461 find_function_data (decl)
465 for (p = outer_function_chain; p; p = p->next)
471 /* Save the current context for compilation of a nested function.
472 This is called from language-specific code.
473 The caller is responsible for saving any language-specific status,
474 since this function knows only about language-independent variables. */
477 push_function_context_to (context)
480 struct function *p = (struct function *) xmalloc (sizeof (struct function));
482 p->next = outer_function_chain;
483 outer_function_chain = p;
485 p->name = current_function_name;
486 p->decl = current_function_decl;
487 p->pops_args = current_function_pops_args;
488 p->returns_struct = current_function_returns_struct;
489 p->returns_pcc_struct = current_function_returns_pcc_struct;
490 p->needs_context = current_function_needs_context;
491 p->calls_setjmp = current_function_calls_setjmp;
492 p->calls_longjmp = current_function_calls_longjmp;
493 p->calls_alloca = current_function_calls_alloca;
494 p->has_nonlocal_label = current_function_has_nonlocal_label;
495 p->has_nonlocal_goto = current_function_has_nonlocal_goto;
496 p->contains_functions = current_function_contains_functions;
497 p->args_size = current_function_args_size;
498 p->pretend_args_size = current_function_pretend_args_size;
499 p->arg_offset_rtx = current_function_arg_offset_rtx;
500 p->varargs = current_function_varargs;
501 p->stdarg = current_function_stdarg;
502 p->uses_const_pool = current_function_uses_const_pool;
503 p->uses_pic_offset_table = current_function_uses_pic_offset_table;
504 p->internal_arg_pointer = current_function_internal_arg_pointer;
505 p->max_parm_reg = max_parm_reg;
506 p->parm_reg_stack_loc = parm_reg_stack_loc;
507 p->outgoing_args_size = current_function_outgoing_args_size;
508 p->return_rtx = current_function_return_rtx;
509 p->nonlocal_goto_handler_slot = nonlocal_goto_handler_slot;
510 p->nonlocal_goto_stack_level = nonlocal_goto_stack_level;
511 p->nonlocal_labels = nonlocal_labels;
512 p->cleanup_label = cleanup_label;
513 p->return_label = return_label;
514 p->save_expr_regs = save_expr_regs;
515 p->stack_slot_list = stack_slot_list;
516 p->parm_birth_insn = parm_birth_insn;
517 p->frame_offset = frame_offset;
518 p->tail_recursion_label = tail_recursion_label;
519 p->tail_recursion_reentry = tail_recursion_reentry;
520 p->arg_pointer_save_area = arg_pointer_save_area;
521 p->rtl_expr_chain = rtl_expr_chain;
522 p->last_parm_insn = last_parm_insn;
523 p->context_display = context_display;
524 p->trampoline_list = trampoline_list;
525 p->function_call_count = function_call_count;
526 p->temp_slots = temp_slots;
527 p->temp_slot_level = temp_slot_level;
528 p->fixup_var_refs_queue = 0;
529 p->epilogue_delay_list = current_function_epilogue_delay_list;
531 save_tree_status (p, context);
532 save_storage_status (p);
533 save_emit_status (p);
535 save_expr_status (p);
536 save_stmt_status (p);
537 save_varasm_status (p);
539 if (save_machine_status)
540 (*save_machine_status) (p);
544 push_function_context ()
546 push_function_context_to (current_function_decl);
549 /* Restore the last saved context, at the end of a nested function.
550 This function is called from language-specific code. */
553 pop_function_context_from (context)
556 struct function *p = outer_function_chain;
558 outer_function_chain = p->next;
560 current_function_contains_functions
561 = p->contains_functions || p->inline_obstacks
562 || context == current_function_decl;
563 current_function_name = p->name;
564 current_function_decl = p->decl;
565 current_function_pops_args = p->pops_args;
566 current_function_returns_struct = p->returns_struct;
567 current_function_returns_pcc_struct = p->returns_pcc_struct;
568 current_function_needs_context = p->needs_context;
569 current_function_calls_setjmp = p->calls_setjmp;
570 current_function_calls_longjmp = p->calls_longjmp;
571 current_function_calls_alloca = p->calls_alloca;
572 current_function_has_nonlocal_label = p->has_nonlocal_label;
573 current_function_has_nonlocal_goto = p->has_nonlocal_goto;
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 current_function_epilogue_delay_list = p->epilogue_delay_list;
608 restore_tree_status (p);
609 restore_storage_status (p);
610 restore_expr_status (p);
611 restore_emit_status (p);
612 restore_stmt_status (p);
613 restore_varasm_status (p);
615 if (restore_machine_status)
616 (*restore_machine_status) (p);
618 /* Finish doing put_var_into_stack for any of our variables
619 which became addressable during the nested function. */
621 struct var_refs_queue *queue = p->fixup_var_refs_queue;
622 for (; queue; queue = queue->next)
623 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. */
808 assign_stack_temp (mode, size, keep)
809 enum machine_mode mode;
813 struct temp_slot *p, *best_p = 0;
815 /* If SIZE is -1 it means that somebody tried to allocate a temporary
816 of a variable size. */
820 /* First try to find an available, already-allocated temporary that is the
821 exact size we require. */
822 for (p = temp_slots; p; p = p->next)
823 if (p->size == size && GET_MODE (p->slot) == mode && ! p->in_use)
826 /* If we didn't find, one, try one that is larger than what we want. We
827 find the smallest such. */
829 for (p = temp_slots; p; p = p->next)
830 if (p->size > size && GET_MODE (p->slot) == mode && ! p->in_use
831 && (best_p == 0 || best_p->size > p->size))
834 /* Make our best, if any, the one to use. */
837 /* If there are enough aligned bytes left over, make them into a new
838 temp_slot so that the extra bytes don't get wasted. Do this only
839 for BLKmode slots, so that we can be sure of the alignment. */
840 if (GET_MODE (best_p->slot) == BLKmode)
842 int alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
843 int rounded_size = CEIL_ROUND (size, alignment);
845 if (best_p->size - rounded_size >= alignment)
847 p = (struct temp_slot *) oballoc (sizeof (struct temp_slot));
848 p->in_use = p->addr_taken = 0;
849 p->size = best_p->size - rounded_size;
850 p->base_offset = best_p->base_offset + rounded_size;
851 p->full_size = best_p->full_size - rounded_size;
852 p->slot = gen_rtx (MEM, BLKmode,
853 plus_constant (XEXP (best_p->slot, 0),
857 p->next = temp_slots;
860 stack_slot_list = gen_rtx (EXPR_LIST, VOIDmode, p->slot,
863 best_p->size = rounded_size;
864 best_p->full_size = rounded_size;
871 /* If we still didn't find one, make a new temporary. */
874 int frame_offset_old = frame_offset;
875 p = (struct temp_slot *) oballoc (sizeof (struct temp_slot));
876 /* If the temp slot mode doesn't indicate the alignment,
877 use the largest possible, so no one will be disappointed. */
878 p->slot = assign_stack_local (mode, size, mode == BLKmode ? -1 : 0);
879 /* The following slot size computation is necessary because we don't
880 know the actual size of the temporary slot until assign_stack_local
881 has performed all the frame alignment and size rounding for the
882 requested temporary. Note that extra space added for alignment
883 can be either above or below this stack slot depending on which
884 way the frame grows. We include the extra space if and only if it
885 is above this slot. */
886 #ifdef FRAME_GROWS_DOWNWARD
887 p->size = frame_offset_old - frame_offset;
891 /* Now define the fields used by combine_temp_slots. */
892 #ifdef FRAME_GROWS_DOWNWARD
893 p->base_offset = frame_offset;
894 p->full_size = frame_offset_old - frame_offset;
896 p->base_offset = frame_offset_old;
897 p->full_size = frame_offset - frame_offset_old;
900 p->next = temp_slots;
906 p->rtl_expr = sequence_rtl_expr;
910 p->level = target_temp_slot_level;
915 p->level = temp_slot_level;
921 /* Combine temporary stack slots which are adjacent on the stack.
923 This allows for better use of already allocated stack space. This is only
924 done for BLKmode slots because we can be sure that we won't have alignment
925 problems in this case. */
928 combine_temp_slots ()
930 struct temp_slot *p, *q;
931 struct temp_slot *prev_p, *prev_q;
932 /* Determine where to free back to after this function. */
933 rtx free_pointer = rtx_alloc (CONST_INT);
935 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
938 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
939 for (q = p->next, prev_q = p; q; q = prev_q->next)
942 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
944 if (p->base_offset + p->full_size == q->base_offset)
946 /* Q comes after P; combine Q into P. */
948 p->full_size += q->full_size;
951 else if (q->base_offset + q->full_size == p->base_offset)
953 /* P comes after Q; combine P into Q. */
955 q->full_size += p->full_size;
960 /* Either delete Q or advance past it. */
962 prev_q->next = q->next;
966 /* Either delete P or advance past it. */
970 prev_p->next = p->next;
972 temp_slots = p->next;
978 /* Free all the RTL made by plus_constant. */
979 rtx_free (free_pointer);
982 /* Find the temp slot corresponding to the object at address X. */
984 static struct temp_slot *
985 find_temp_slot_from_address (x)
991 for (p = temp_slots; p; p = p->next)
995 else if (XEXP (p->slot, 0) == x
999 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
1000 for (next = p->address; next; next = XEXP (next, 1))
1001 if (XEXP (next, 0) == x)
1008 /* Indicate that NEW is an alternate way of referring to the temp slot
1009 that previous was known by OLD. */
1012 update_temp_slot_address (old, new)
1015 struct temp_slot *p = find_temp_slot_from_address (old);
1017 /* If none, return. Else add NEW as an alias. */
1020 else if (p->address == 0)
1024 if (GET_CODE (p->address) != EXPR_LIST)
1025 p->address = gen_rtx (EXPR_LIST, VOIDmode, p->address, NULL_RTX);
1027 p->address = gen_rtx (EXPR_LIST, VOIDmode, new, p->address);
1031 /* If X could be a reference to a temporary slot, mark the fact that its
1032 address was taken. */
1035 mark_temp_addr_taken (x)
1038 struct temp_slot *p;
1043 /* If X is not in memory or is at a constant address, it cannot be in
1044 a temporary slot. */
1045 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1048 p = find_temp_slot_from_address (XEXP (x, 0));
1053 /* If X could be a reference to a temporary slot, mark that slot as belonging
1054 to the to one level higher. If X matched one of our slots, just mark that
1055 one. Otherwise, we can't easily predict which it is, so upgrade all of
1056 them. Kept slots need not be touched.
1058 This is called when an ({...}) construct occurs and a statement
1059 returns a value in memory. */
1062 preserve_temp_slots (x)
1065 struct temp_slot *p = 0;
1067 /* If there is no result, we still might have some objects whose address
1068 were taken, so we need to make sure they stay around. */
1071 for (p = temp_slots; p; p = p->next)
1072 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1078 /* If X is a register that is being used as a pointer, see if we have
1079 a temporary slot we know it points to. To be consistent with
1080 the code below, we really should preserve all non-kept slots
1081 if we can't find a match, but that seems to be much too costly. */
1082 if (GET_CODE (x) == REG && REGNO_POINTER_FLAG (REGNO (x)))
1083 p = find_temp_slot_from_address (x);
1085 /* If X is not in memory or is at a constant address, it cannot be in
1086 a temporary slot, but it can contain something whose address was
1088 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1090 for (p = temp_slots; p; p = p->next)
1091 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1097 /* First see if we can find a match. */
1099 p = find_temp_slot_from_address (XEXP (x, 0));
1103 /* Move everything at our level whose address was taken to our new
1104 level in case we used its address. */
1105 struct temp_slot *q;
1107 for (q = temp_slots; q; q = q->next)
1108 if (q != p && q->addr_taken && q->level == p->level)
1116 /* Otherwise, preserve all non-kept slots at this level. */
1117 for (p = temp_slots; p; p = p->next)
1118 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1122 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1123 with that RTL_EXPR, promote it into a temporary slot at the present
1124 level so it will not be freed when we free slots made in the
1128 preserve_rtl_expr_result (x)
1131 struct temp_slot *p;
1133 /* If X is not in memory or is at a constant address, it cannot be in
1134 a temporary slot. */
1135 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1138 /* If we can find a match, move it to our level unless it is already at
1140 p = find_temp_slot_from_address (XEXP (x, 0));
1143 p->level = MIN (p->level, temp_slot_level);
1150 /* Free all temporaries used so far. This is normally called at the end
1151 of generating code for a statement. Don't free any temporaries
1152 currently in use for an RTL_EXPR that hasn't yet been emitted.
1153 We could eventually do better than this since it can be reused while
1154 generating the same RTL_EXPR, but this is complex and probably not
1160 struct temp_slot *p;
1162 for (p = temp_slots; p; p = p->next)
1163 if (p->in_use && p->level == temp_slot_level && ! p->keep
1164 && p->rtl_expr == 0)
1167 combine_temp_slots ();
1170 /* Free all temporary slots used in T, an RTL_EXPR node. */
1173 free_temps_for_rtl_expr (t)
1176 struct temp_slot *p;
1178 for (p = temp_slots; p; p = p->next)
1179 if (p->rtl_expr == t)
1182 combine_temp_slots ();
1185 /* Push deeper into the nesting level for stack temporaries. */
1193 /* Pop a temporary nesting level. All slots in use in the current level
1199 struct temp_slot *p;
1201 for (p = temp_slots; p; p = p->next)
1202 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1205 combine_temp_slots ();
1210 /* Retroactively move an auto variable from a register to a stack slot.
1211 This is done when an address-reference to the variable is seen. */
1214 put_var_into_stack (decl)
1218 enum machine_mode promoted_mode, decl_mode;
1219 struct function *function = 0;
1222 if (output_bytecode)
1225 context = decl_function_context (decl);
1227 /* Get the current rtl used for this object and it's original mode. */
1228 reg = TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl) : DECL_RTL (decl);
1230 /* No need to do anything if decl has no rtx yet
1231 since in that case caller is setting TREE_ADDRESSABLE
1232 and a stack slot will be assigned when the rtl is made. */
1236 /* Get the declared mode for this object. */
1237 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1238 : DECL_MODE (decl));
1239 /* Get the mode it's actually stored in. */
1240 promoted_mode = GET_MODE (reg);
1242 /* If this variable comes from an outer function,
1243 find that function's saved context. */
1244 if (context != current_function_decl)
1245 for (function = outer_function_chain; function; function = function->next)
1246 if (function->decl == context)
1249 /* If this is a variable-size object with a pseudo to address it,
1250 put that pseudo into the stack, if the var is nonlocal. */
1251 if (DECL_NONLOCAL (decl)
1252 && GET_CODE (reg) == MEM
1253 && GET_CODE (XEXP (reg, 0)) == REG
1254 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1256 reg = XEXP (reg, 0);
1257 decl_mode = promoted_mode = GET_MODE (reg);
1260 /* Now we should have a value that resides in one or more pseudo regs. */
1262 if (GET_CODE (reg) == REG)
1263 put_reg_into_stack (function, reg, TREE_TYPE (decl),
1264 promoted_mode, decl_mode);
1265 else if (GET_CODE (reg) == CONCAT)
1267 /* A CONCAT contains two pseudos; put them both in the stack.
1268 We do it so they end up consecutive. */
1269 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1270 tree part_type = TREE_TYPE (TREE_TYPE (decl));
1271 #ifdef FRAME_GROWS_DOWNWARD
1272 /* Since part 0 should have a lower address, do it second. */
1273 put_reg_into_stack (function, XEXP (reg, 1),
1274 part_type, part_mode, part_mode);
1275 put_reg_into_stack (function, XEXP (reg, 0),
1276 part_type, part_mode, part_mode);
1278 put_reg_into_stack (function, XEXP (reg, 0),
1279 part_type, part_mode, part_mode);
1280 put_reg_into_stack (function, XEXP (reg, 1),
1281 part_type, part_mode, part_mode);
1284 /* Change the CONCAT into a combined MEM for both parts. */
1285 PUT_CODE (reg, MEM);
1286 /* The two parts are in memory order already.
1287 Use the lower parts address as ours. */
1288 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1289 /* Prevent sharing of rtl that might lose. */
1290 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1291 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1295 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1296 into the stack frame of FUNCTION (0 means the current function).
1297 DECL_MODE is the machine mode of the user-level data type.
1298 PROMOTED_MODE is the machine mode of the register. */
1301 put_reg_into_stack (function, reg, type, promoted_mode, decl_mode)
1302 struct function *function;
1305 enum machine_mode promoted_mode, decl_mode;
1311 if (REGNO (reg) < function->max_parm_reg)
1312 new = function->parm_reg_stack_loc[REGNO (reg)];
1314 new = assign_outer_stack_local (decl_mode, GET_MODE_SIZE (decl_mode),
1319 if (REGNO (reg) < max_parm_reg)
1320 new = parm_reg_stack_loc[REGNO (reg)];
1322 new = assign_stack_local (decl_mode, GET_MODE_SIZE (decl_mode), 0);
1325 XEXP (reg, 0) = XEXP (new, 0);
1326 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1327 REG_USERVAR_P (reg) = 0;
1328 PUT_CODE (reg, MEM);
1329 PUT_MODE (reg, decl_mode);
1331 /* If this is a memory ref that contains aggregate components,
1332 mark it as such for cse and loop optimize. */
1333 MEM_IN_STRUCT_P (reg) = AGGREGATE_TYPE_P (type);
1335 /* Now make sure that all refs to the variable, previously made
1336 when it was a register, are fixed up to be valid again. */
1339 struct var_refs_queue *temp;
1341 /* Variable is inherited; fix it up when we get back to its function. */
1342 push_obstacks (function->function_obstack,
1343 function->function_maybepermanent_obstack);
1345 /* See comment in restore_tree_status in tree.c for why this needs to be
1346 on saveable obstack. */
1348 = (struct var_refs_queue *) savealloc (sizeof (struct var_refs_queue));
1349 temp->modified = reg;
1350 temp->promoted_mode = promoted_mode;
1351 temp->unsignedp = TREE_UNSIGNED (type);
1352 temp->next = function->fixup_var_refs_queue;
1353 function->fixup_var_refs_queue = temp;
1357 /* Variable is local; fix it up now. */
1358 fixup_var_refs (reg, promoted_mode, TREE_UNSIGNED (type));
1362 fixup_var_refs (var, promoted_mode, unsignedp)
1364 enum machine_mode promoted_mode;
1368 rtx first_insn = get_insns ();
1369 struct sequence_stack *stack = sequence_stack;
1370 tree rtl_exps = rtl_expr_chain;
1372 /* Must scan all insns for stack-refs that exceed the limit. */
1373 fixup_var_refs_insns (var, promoted_mode, unsignedp, first_insn, stack == 0);
1375 /* Scan all pending sequences too. */
1376 for (; stack; stack = stack->next)
1378 push_to_sequence (stack->first);
1379 fixup_var_refs_insns (var, promoted_mode, unsignedp,
1380 stack->first, stack->next != 0);
1381 /* Update remembered end of sequence
1382 in case we added an insn at the end. */
1383 stack->last = get_last_insn ();
1387 /* Scan all waiting RTL_EXPRs too. */
1388 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1390 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1391 if (seq != const0_rtx && seq != 0)
1393 push_to_sequence (seq);
1394 fixup_var_refs_insns (var, promoted_mode, unsignedp, seq, 0);
1400 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1401 some part of an insn. Return a struct fixup_replacement whose OLD
1402 value is equal to X. Allocate a new structure if no such entry exists. */
1404 static struct fixup_replacement *
1405 find_fixup_replacement (replacements, x)
1406 struct fixup_replacement **replacements;
1409 struct fixup_replacement *p;
1411 /* See if we have already replaced this. */
1412 for (p = *replacements; p && p->old != x; p = p->next)
1417 p = (struct fixup_replacement *) oballoc (sizeof (struct fixup_replacement));
1420 p->next = *replacements;
1427 /* Scan the insn-chain starting with INSN for refs to VAR
1428 and fix them up. TOPLEVEL is nonzero if this chain is the
1429 main chain of insns for the current function. */
1432 fixup_var_refs_insns (var, promoted_mode, unsignedp, insn, toplevel)
1434 enum machine_mode promoted_mode;
1443 rtx next = NEXT_INSN (insn);
1445 if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
1447 /* If this is a CLOBBER of VAR, delete it.
1449 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1450 and REG_RETVAL notes too. */
1451 if (GET_CODE (PATTERN (insn)) == CLOBBER
1452 && XEXP (PATTERN (insn), 0) == var)
1454 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1455 /* The REG_LIBCALL note will go away since we are going to
1456 turn INSN into a NOTE, so just delete the
1457 corresponding REG_RETVAL note. */
1458 remove_note (XEXP (note, 0),
1459 find_reg_note (XEXP (note, 0), REG_RETVAL,
1462 /* In unoptimized compilation, we shouldn't call delete_insn
1463 except in jump.c doing warnings. */
1464 PUT_CODE (insn, NOTE);
1465 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1466 NOTE_SOURCE_FILE (insn) = 0;
1469 /* The insn to load VAR from a home in the arglist
1470 is now a no-op. When we see it, just delete it. */
1472 && GET_CODE (PATTERN (insn)) == SET
1473 && SET_DEST (PATTERN (insn)) == var
1474 /* If this represents the result of an insn group,
1475 don't delete the insn. */
1476 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1477 && rtx_equal_p (SET_SRC (PATTERN (insn)), var))
1479 /* In unoptimized compilation, we shouldn't call delete_insn
1480 except in jump.c doing warnings. */
1481 PUT_CODE (insn, NOTE);
1482 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1483 NOTE_SOURCE_FILE (insn) = 0;
1484 if (insn == last_parm_insn)
1485 last_parm_insn = PREV_INSN (next);
1489 struct fixup_replacement *replacements = 0;
1490 rtx next_insn = NEXT_INSN (insn);
1492 #ifdef SMALL_REGISTER_CLASSES
1493 /* If the insn that copies the results of a CALL_INSN
1494 into a pseudo now references VAR, we have to use an
1495 intermediate pseudo since we want the life of the
1496 return value register to be only a single insn.
1498 If we don't use an intermediate pseudo, such things as
1499 address computations to make the address of VAR valid
1500 if it is not can be placed between the CALL_INSN and INSN.
1502 To make sure this doesn't happen, we record the destination
1503 of the CALL_INSN and see if the next insn uses both that
1506 if (call_dest != 0 && GET_CODE (insn) == INSN
1507 && reg_mentioned_p (var, PATTERN (insn))
1508 && reg_mentioned_p (call_dest, PATTERN (insn)))
1510 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1512 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1514 PATTERN (insn) = replace_rtx (PATTERN (insn),
1518 if (GET_CODE (insn) == CALL_INSN
1519 && GET_CODE (PATTERN (insn)) == SET)
1520 call_dest = SET_DEST (PATTERN (insn));
1521 else if (GET_CODE (insn) == CALL_INSN
1522 && GET_CODE (PATTERN (insn)) == PARALLEL
1523 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1524 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1529 /* See if we have to do anything to INSN now that VAR is in
1530 memory. If it needs to be loaded into a pseudo, use a single
1531 pseudo for the entire insn in case there is a MATCH_DUP
1532 between two operands. We pass a pointer to the head of
1533 a list of struct fixup_replacements. If fixup_var_refs_1
1534 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1535 it will record them in this list.
1537 If it allocated a pseudo for any replacement, we copy into
1540 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1543 /* If this is last_parm_insn, and any instructions were output
1544 after it to fix it up, then we must set last_parm_insn to
1545 the last such instruction emitted. */
1546 if (insn == last_parm_insn)
1547 last_parm_insn = PREV_INSN (next_insn);
1549 while (replacements)
1551 if (GET_CODE (replacements->new) == REG)
1556 /* OLD might be a (subreg (mem)). */
1557 if (GET_CODE (replacements->old) == SUBREG)
1559 = fixup_memory_subreg (replacements->old, insn, 0);
1562 = fixup_stack_1 (replacements->old, insn);
1564 insert_before = insn;
1566 /* If we are changing the mode, do a conversion.
1567 This might be wasteful, but combine.c will
1568 eliminate much of the waste. */
1570 if (GET_MODE (replacements->new)
1571 != GET_MODE (replacements->old))
1574 convert_move (replacements->new,
1575 replacements->old, unsignedp);
1576 seq = gen_sequence ();
1580 seq = gen_move_insn (replacements->new,
1583 emit_insn_before (seq, insert_before);
1586 replacements = replacements->next;
1590 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1591 But don't touch other insns referred to by reg-notes;
1592 we will get them elsewhere. */
1593 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
1594 if (GET_CODE (note) != INSN_LIST)
1596 = walk_fixup_memory_subreg (XEXP (note, 0), insn, 1);
1602 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1603 See if the rtx expression at *LOC in INSN needs to be changed.
1605 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1606 contain a list of original rtx's and replacements. If we find that we need
1607 to modify this insn by replacing a memory reference with a pseudo or by
1608 making a new MEM to implement a SUBREG, we consult that list to see if
1609 we have already chosen a replacement. If none has already been allocated,
1610 we allocate it and update the list. fixup_var_refs_insns will copy VAR
1611 or the SUBREG, as appropriate, to the pseudo. */
1614 fixup_var_refs_1 (var, promoted_mode, loc, insn, replacements)
1616 enum machine_mode promoted_mode;
1619 struct fixup_replacement **replacements;
1622 register rtx x = *loc;
1623 RTX_CODE code = GET_CODE (x);
1625 register rtx tem, tem1;
1626 struct fixup_replacement *replacement;
1633 /* If we already have a replacement, use it. Otherwise,
1634 try to fix up this address in case it is invalid. */
1636 replacement = find_fixup_replacement (replacements, var);
1637 if (replacement->new)
1639 *loc = replacement->new;
1643 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1645 /* Unless we are forcing memory to register or we changed the mode,
1646 we can leave things the way they are if the insn is valid. */
1648 INSN_CODE (insn) = -1;
1649 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1650 && recog_memoized (insn) >= 0)
1653 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1657 /* If X contains VAR, we need to unshare it here so that we update
1658 each occurrence separately. But all identical MEMs in one insn
1659 must be replaced with the same rtx because of the possibility of
1662 if (reg_mentioned_p (var, x))
1664 replacement = find_fixup_replacement (replacements, x);
1665 if (replacement->new == 0)
1666 replacement->new = copy_most_rtx (x, var);
1668 *loc = x = replacement->new;
1684 /* Note that in some cases those types of expressions are altered
1685 by optimize_bit_field, and do not survive to get here. */
1686 if (XEXP (x, 0) == var
1687 || (GET_CODE (XEXP (x, 0)) == SUBREG
1688 && SUBREG_REG (XEXP (x, 0)) == var))
1690 /* Get TEM as a valid MEM in the mode presently in the insn.
1692 We don't worry about the possibility of MATCH_DUP here; it
1693 is highly unlikely and would be tricky to handle. */
1696 if (GET_CODE (tem) == SUBREG)
1697 tem = fixup_memory_subreg (tem, insn, 1);
1698 tem = fixup_stack_1 (tem, insn);
1700 /* Unless we want to load from memory, get TEM into the proper mode
1701 for an extract from memory. This can only be done if the
1702 extract is at a constant position and length. */
1704 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
1705 && GET_CODE (XEXP (x, 2)) == CONST_INT
1706 && ! mode_dependent_address_p (XEXP (tem, 0))
1707 && ! MEM_VOLATILE_P (tem))
1709 enum machine_mode wanted_mode = VOIDmode;
1710 enum machine_mode is_mode = GET_MODE (tem);
1711 int width = INTVAL (XEXP (x, 1));
1712 int pos = INTVAL (XEXP (x, 2));
1715 if (GET_CODE (x) == ZERO_EXTRACT)
1716 wanted_mode = insn_operand_mode[(int) CODE_FOR_extzv][1];
1719 if (GET_CODE (x) == SIGN_EXTRACT)
1720 wanted_mode = insn_operand_mode[(int) CODE_FOR_extv][1];
1722 /* If we have a narrower mode, we can do something. */
1723 if (wanted_mode != VOIDmode
1724 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
1726 int offset = pos / BITS_PER_UNIT;
1727 rtx old_pos = XEXP (x, 2);
1730 /* If the bytes and bits are counted differently, we
1731 must adjust the offset. */
1732 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
1733 offset = (GET_MODE_SIZE (is_mode)
1734 - GET_MODE_SIZE (wanted_mode) - offset);
1736 pos %= GET_MODE_BITSIZE (wanted_mode);
1738 newmem = gen_rtx (MEM, wanted_mode,
1739 plus_constant (XEXP (tem, 0), offset));
1740 RTX_UNCHANGING_P (newmem) = RTX_UNCHANGING_P (tem);
1741 MEM_VOLATILE_P (newmem) = MEM_VOLATILE_P (tem);
1742 MEM_IN_STRUCT_P (newmem) = MEM_IN_STRUCT_P (tem);
1744 /* Make the change and see if the insn remains valid. */
1745 INSN_CODE (insn) = -1;
1746 XEXP (x, 0) = newmem;
1747 XEXP (x, 2) = GEN_INT (pos);
1749 if (recog_memoized (insn) >= 0)
1752 /* Otherwise, restore old position. XEXP (x, 0) will be
1754 XEXP (x, 2) = old_pos;
1758 /* If we get here, the bitfield extract insn can't accept a memory
1759 reference. Copy the input into a register. */
1761 tem1 = gen_reg_rtx (GET_MODE (tem));
1762 emit_insn_before (gen_move_insn (tem1, tem), insn);
1769 if (SUBREG_REG (x) == var)
1771 /* If this is a special SUBREG made because VAR was promoted
1772 from a wider mode, replace it with VAR and call ourself
1773 recursively, this time saying that the object previously
1774 had its current mode (by virtue of the SUBREG). */
1776 if (SUBREG_PROMOTED_VAR_P (x))
1779 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements);
1783 /* If this SUBREG makes VAR wider, it has become a paradoxical
1784 SUBREG with VAR in memory, but these aren't allowed at this
1785 stage of the compilation. So load VAR into a pseudo and take
1786 a SUBREG of that pseudo. */
1787 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
1789 replacement = find_fixup_replacement (replacements, var);
1790 if (replacement->new == 0)
1791 replacement->new = gen_reg_rtx (GET_MODE (var));
1792 SUBREG_REG (x) = replacement->new;
1796 /* See if we have already found a replacement for this SUBREG.
1797 If so, use it. Otherwise, make a MEM and see if the insn
1798 is recognized. If not, or if we should force MEM into a register,
1799 make a pseudo for this SUBREG. */
1800 replacement = find_fixup_replacement (replacements, x);
1801 if (replacement->new)
1803 *loc = replacement->new;
1807 replacement->new = *loc = fixup_memory_subreg (x, insn, 0);
1809 INSN_CODE (insn) = -1;
1810 if (! flag_force_mem && recog_memoized (insn) >= 0)
1813 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
1819 /* First do special simplification of bit-field references. */
1820 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
1821 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
1822 optimize_bit_field (x, insn, 0);
1823 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
1824 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
1825 optimize_bit_field (x, insn, NULL_PTR);
1827 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
1828 insn into a pseudo and store the low part of the pseudo into VAR. */
1829 if (GET_CODE (SET_DEST (x)) == SUBREG
1830 && SUBREG_REG (SET_DEST (x)) == var
1831 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
1832 > GET_MODE_SIZE (GET_MODE (var))))
1834 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
1835 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
1842 rtx dest = SET_DEST (x);
1843 rtx src = SET_SRC (x);
1844 rtx outerdest = dest;
1846 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
1847 || GET_CODE (dest) == SIGN_EXTRACT
1848 || GET_CODE (dest) == ZERO_EXTRACT)
1849 dest = XEXP (dest, 0);
1851 if (GET_CODE (src) == SUBREG)
1852 src = XEXP (src, 0);
1854 /* If VAR does not appear at the top level of the SET
1855 just scan the lower levels of the tree. */
1857 if (src != var && dest != var)
1860 /* We will need to rerecognize this insn. */
1861 INSN_CODE (insn) = -1;
1864 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var)
1866 /* Since this case will return, ensure we fixup all the
1868 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
1869 insn, replacements);
1870 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
1871 insn, replacements);
1872 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
1873 insn, replacements);
1875 tem = XEXP (outerdest, 0);
1877 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
1878 that may appear inside a ZERO_EXTRACT.
1879 This was legitimate when the MEM was a REG. */
1880 if (GET_CODE (tem) == SUBREG
1881 && SUBREG_REG (tem) == var)
1882 tem = fixup_memory_subreg (tem, insn, 1);
1884 tem = fixup_stack_1 (tem, insn);
1886 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
1887 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
1888 && ! mode_dependent_address_p (XEXP (tem, 0))
1889 && ! MEM_VOLATILE_P (tem))
1891 enum machine_mode wanted_mode
1892 = insn_operand_mode[(int) CODE_FOR_insv][0];
1893 enum machine_mode is_mode = GET_MODE (tem);
1894 int width = INTVAL (XEXP (outerdest, 1));
1895 int pos = INTVAL (XEXP (outerdest, 2));
1897 /* If we have a narrower mode, we can do something. */
1898 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
1900 int offset = pos / BITS_PER_UNIT;
1901 rtx old_pos = XEXP (outerdest, 2);
1904 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
1905 offset = (GET_MODE_SIZE (is_mode)
1906 - GET_MODE_SIZE (wanted_mode) - offset);
1908 pos %= GET_MODE_BITSIZE (wanted_mode);
1910 newmem = gen_rtx (MEM, wanted_mode,
1911 plus_constant (XEXP (tem, 0), offset));
1912 RTX_UNCHANGING_P (newmem) = RTX_UNCHANGING_P (tem);
1913 MEM_VOLATILE_P (newmem) = MEM_VOLATILE_P (tem);
1914 MEM_IN_STRUCT_P (newmem) = MEM_IN_STRUCT_P (tem);
1916 /* Make the change and see if the insn remains valid. */
1917 INSN_CODE (insn) = -1;
1918 XEXP (outerdest, 0) = newmem;
1919 XEXP (outerdest, 2) = GEN_INT (pos);
1921 if (recog_memoized (insn) >= 0)
1924 /* Otherwise, restore old position. XEXP (x, 0) will be
1926 XEXP (outerdest, 2) = old_pos;
1930 /* If we get here, the bit-field store doesn't allow memory
1931 or isn't located at a constant position. Load the value into
1932 a register, do the store, and put it back into memory. */
1934 tem1 = gen_reg_rtx (GET_MODE (tem));
1935 emit_insn_before (gen_move_insn (tem1, tem), insn);
1936 emit_insn_after (gen_move_insn (tem, tem1), insn);
1937 XEXP (outerdest, 0) = tem1;
1942 /* STRICT_LOW_PART is a no-op on memory references
1943 and it can cause combinations to be unrecognizable,
1946 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
1947 SET_DEST (x) = XEXP (SET_DEST (x), 0);
1949 /* A valid insn to copy VAR into or out of a register
1950 must be left alone, to avoid an infinite loop here.
1951 If the reference to VAR is by a subreg, fix that up,
1952 since SUBREG is not valid for a memref.
1953 Also fix up the address of the stack slot.
1955 Note that we must not try to recognize the insn until
1956 after we know that we have valid addresses and no
1957 (subreg (mem ...) ...) constructs, since these interfere
1958 with determining the validity of the insn. */
1960 if ((SET_SRC (x) == var
1961 || (GET_CODE (SET_SRC (x)) == SUBREG
1962 && SUBREG_REG (SET_SRC (x)) == var))
1963 && (GET_CODE (SET_DEST (x)) == REG
1964 || (GET_CODE (SET_DEST (x)) == SUBREG
1965 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
1966 && x == single_set (PATTERN (insn)))
1970 replacement = find_fixup_replacement (replacements, SET_SRC (x));
1971 if (replacement->new)
1972 SET_SRC (x) = replacement->new;
1973 else if (GET_CODE (SET_SRC (x)) == SUBREG)
1974 SET_SRC (x) = replacement->new
1975 = fixup_memory_subreg (SET_SRC (x), insn, 0);
1977 SET_SRC (x) = replacement->new
1978 = fixup_stack_1 (SET_SRC (x), insn);
1980 if (recog_memoized (insn) >= 0)
1983 /* INSN is not valid, but we know that we want to
1984 copy SET_SRC (x) to SET_DEST (x) in some way. So
1985 we generate the move and see whether it requires more
1986 than one insn. If it does, we emit those insns and
1987 delete INSN. Otherwise, we an just replace the pattern
1988 of INSN; we have already verified above that INSN has
1989 no other function that to do X. */
1991 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
1992 if (GET_CODE (pat) == SEQUENCE)
1994 emit_insn_after (pat, insn);
1995 PUT_CODE (insn, NOTE);
1996 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1997 NOTE_SOURCE_FILE (insn) = 0;
2000 PATTERN (insn) = pat;
2005 if ((SET_DEST (x) == var
2006 || (GET_CODE (SET_DEST (x)) == SUBREG
2007 && SUBREG_REG (SET_DEST (x)) == var))
2008 && (GET_CODE (SET_SRC (x)) == REG
2009 || (GET_CODE (SET_SRC (x)) == SUBREG
2010 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2011 && x == single_set (PATTERN (insn)))
2015 if (GET_CODE (SET_DEST (x)) == SUBREG)
2016 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn, 0);
2018 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2020 if (recog_memoized (insn) >= 0)
2023 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2024 if (GET_CODE (pat) == SEQUENCE)
2026 emit_insn_after (pat, insn);
2027 PUT_CODE (insn, NOTE);
2028 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
2029 NOTE_SOURCE_FILE (insn) = 0;
2032 PATTERN (insn) = pat;
2037 /* Otherwise, storing into VAR must be handled specially
2038 by storing into a temporary and copying that into VAR
2039 with a new insn after this one. Note that this case
2040 will be used when storing into a promoted scalar since
2041 the insn will now have different modes on the input
2042 and output and hence will be invalid (except for the case
2043 of setting it to a constant, which does not need any
2044 change if it is valid). We generate extra code in that case,
2045 but combine.c will eliminate it. */
2050 rtx fixeddest = SET_DEST (x);
2052 /* STRICT_LOW_PART can be discarded, around a MEM. */
2053 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2054 fixeddest = XEXP (fixeddest, 0);
2055 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2056 if (GET_CODE (fixeddest) == SUBREG)
2057 fixeddest = fixup_memory_subreg (fixeddest, insn, 0);
2059 fixeddest = fixup_stack_1 (fixeddest, insn);
2061 temp = gen_reg_rtx (GET_MODE (SET_SRC (x)) == VOIDmode
2062 ? GET_MODE (fixeddest)
2063 : GET_MODE (SET_SRC (x)));
2065 emit_insn_after (gen_move_insn (fixeddest,
2066 gen_lowpart (GET_MODE (fixeddest),
2070 SET_DEST (x) = temp;
2075 /* Nothing special about this RTX; fix its operands. */
2077 fmt = GET_RTX_FORMAT (code);
2078 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2081 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements);
2085 for (j = 0; j < XVECLEN (x, i); j++)
2086 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2087 insn, replacements);
2092 /* Given X, an rtx of the form (SUBREG:m1 (MEM:m2 addr)),
2093 return an rtx (MEM:m1 newaddr) which is equivalent.
2094 If any insns must be emitted to compute NEWADDR, put them before INSN.
2096 UNCRITICAL nonzero means accept paradoxical subregs.
2097 This is used for subregs found inside of ZERO_EXTRACTs and in REG_NOTES. */
2100 fixup_memory_subreg (x, insn, uncritical)
2105 int offset = SUBREG_WORD (x) * UNITS_PER_WORD;
2106 rtx addr = XEXP (SUBREG_REG (x), 0);
2107 enum machine_mode mode = GET_MODE (x);
2110 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2111 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))
2115 if (BYTES_BIG_ENDIAN)
2116 offset += (MIN (UNITS_PER_WORD, GET_MODE_SIZE (GET_MODE (SUBREG_REG (x))))
2117 - MIN (UNITS_PER_WORD, GET_MODE_SIZE (mode)));
2118 addr = plus_constant (addr, offset);
2119 if (!flag_force_addr && memory_address_p (mode, addr))
2120 /* Shortcut if no insns need be emitted. */
2121 return change_address (SUBREG_REG (x), mode, addr);
2123 result = change_address (SUBREG_REG (x), mode, addr);
2124 emit_insn_before (gen_sequence (), insn);
2129 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2130 Replace subexpressions of X in place.
2131 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2132 Otherwise return X, with its contents possibly altered.
2134 If any insns must be emitted to compute NEWADDR, put them before INSN.
2136 UNCRITICAL is as in fixup_memory_subreg. */
2139 walk_fixup_memory_subreg (x, insn, uncritical)
2144 register enum rtx_code code;
2151 code = GET_CODE (x);
2153 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2154 return fixup_memory_subreg (x, insn, uncritical);
2156 /* Nothing special about this RTX; fix its operands. */
2158 fmt = GET_RTX_FORMAT (code);
2159 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2162 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn, uncritical);
2166 for (j = 0; j < XVECLEN (x, i); j++)
2168 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn, uncritical);
2174 /* For each memory ref within X, if it refers to a stack slot
2175 with an out of range displacement, put the address in a temp register
2176 (emitting new insns before INSN to load these registers)
2177 and alter the memory ref to use that register.
2178 Replace each such MEM rtx with a copy, to avoid clobberage. */
2181 fixup_stack_1 (x, insn)
2186 register RTX_CODE code = GET_CODE (x);
2191 register rtx ad = XEXP (x, 0);
2192 /* If we have address of a stack slot but it's not valid
2193 (displacement is too large), compute the sum in a register. */
2194 if (GET_CODE (ad) == PLUS
2195 && GET_CODE (XEXP (ad, 0)) == REG
2196 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2197 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2198 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2199 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2202 if (memory_address_p (GET_MODE (x), ad))
2206 temp = copy_to_reg (ad);
2207 seq = gen_sequence ();
2209 emit_insn_before (seq, insn);
2210 return change_address (x, VOIDmode, temp);
2215 fmt = GET_RTX_FORMAT (code);
2216 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2219 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2223 for (j = 0; j < XVECLEN (x, i); j++)
2224 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2230 /* Optimization: a bit-field instruction whose field
2231 happens to be a byte or halfword in memory
2232 can be changed to a move instruction.
2234 We call here when INSN is an insn to examine or store into a bit-field.
2235 BODY is the SET-rtx to be altered.
2237 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2238 (Currently this is called only from function.c, and EQUIV_MEM
2242 optimize_bit_field (body, insn, equiv_mem)
2247 register rtx bitfield;
2250 enum machine_mode mode;
2252 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2253 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2254 bitfield = SET_DEST (body), destflag = 1;
2256 bitfield = SET_SRC (body), destflag = 0;
2258 /* First check that the field being stored has constant size and position
2259 and is in fact a byte or halfword suitably aligned. */
2261 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2262 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2263 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2265 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2267 register rtx memref = 0;
2269 /* Now check that the containing word is memory, not a register,
2270 and that it is safe to change the machine mode. */
2272 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2273 memref = XEXP (bitfield, 0);
2274 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2276 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2277 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2278 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2279 memref = SUBREG_REG (XEXP (bitfield, 0));
2280 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2282 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2283 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2286 && ! mode_dependent_address_p (XEXP (memref, 0))
2287 && ! MEM_VOLATILE_P (memref))
2289 /* Now adjust the address, first for any subreg'ing
2290 that we are now getting rid of,
2291 and then for which byte of the word is wanted. */
2293 register int offset = INTVAL (XEXP (bitfield, 2));
2296 /* Adjust OFFSET to count bits from low-address byte. */
2297 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2298 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2299 - offset - INTVAL (XEXP (bitfield, 1)));
2301 /* Adjust OFFSET to count bytes from low-address byte. */
2302 offset /= BITS_PER_UNIT;
2303 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2305 offset += SUBREG_WORD (XEXP (bitfield, 0)) * UNITS_PER_WORD;
2306 if (BYTES_BIG_ENDIAN)
2307 offset -= (MIN (UNITS_PER_WORD,
2308 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2309 - MIN (UNITS_PER_WORD,
2310 GET_MODE_SIZE (GET_MODE (memref))));
2314 memref = change_address (memref, mode,
2315 plus_constant (XEXP (memref, 0), offset));
2316 insns = get_insns ();
2318 emit_insns_before (insns, insn);
2320 /* Store this memory reference where
2321 we found the bit field reference. */
2325 validate_change (insn, &SET_DEST (body), memref, 1);
2326 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2328 rtx src = SET_SRC (body);
2329 while (GET_CODE (src) == SUBREG
2330 && SUBREG_WORD (src) == 0)
2331 src = SUBREG_REG (src);
2332 if (GET_MODE (src) != GET_MODE (memref))
2333 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2334 validate_change (insn, &SET_SRC (body), src, 1);
2336 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2337 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2338 /* This shouldn't happen because anything that didn't have
2339 one of these modes should have got converted explicitly
2340 and then referenced through a subreg.
2341 This is so because the original bit-field was
2342 handled by agg_mode and so its tree structure had
2343 the same mode that memref now has. */
2348 rtx dest = SET_DEST (body);
2350 while (GET_CODE (dest) == SUBREG
2351 && SUBREG_WORD (dest) == 0
2352 && (GET_MODE_CLASS (GET_MODE (dest))
2353 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest)))))
2354 dest = SUBREG_REG (dest);
2356 validate_change (insn, &SET_DEST (body), dest, 1);
2358 if (GET_MODE (dest) == GET_MODE (memref))
2359 validate_change (insn, &SET_SRC (body), memref, 1);
2362 /* Convert the mem ref to the destination mode. */
2363 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2366 convert_move (newreg, memref,
2367 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2371 validate_change (insn, &SET_SRC (body), newreg, 1);
2375 /* See if we can convert this extraction or insertion into
2376 a simple move insn. We might not be able to do so if this
2377 was, for example, part of a PARALLEL.
2379 If we succeed, write out any needed conversions. If we fail,
2380 it is hard to guess why we failed, so don't do anything
2381 special; just let the optimization be suppressed. */
2383 if (apply_change_group () && seq)
2384 emit_insns_before (seq, insn);
2389 /* These routines are responsible for converting virtual register references
2390 to the actual hard register references once RTL generation is complete.
2392 The following four variables are used for communication between the
2393 routines. They contain the offsets of the virtual registers from their
2394 respective hard registers. */
2396 static int in_arg_offset;
2397 static int var_offset;
2398 static int dynamic_offset;
2399 static int out_arg_offset;
2401 /* In most machines, the stack pointer register is equivalent to the bottom
2404 #ifndef STACK_POINTER_OFFSET
2405 #define STACK_POINTER_OFFSET 0
2408 /* If not defined, pick an appropriate default for the offset of dynamically
2409 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2410 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2412 #ifndef STACK_DYNAMIC_OFFSET
2414 #ifdef ACCUMULATE_OUTGOING_ARGS
2415 /* The bottom of the stack points to the actual arguments. If
2416 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2417 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2418 stack space for register parameters is not pushed by the caller, but
2419 rather part of the fixed stack areas and hence not included in
2420 `current_function_outgoing_args_size'. Nevertheless, we must allow
2421 for it when allocating stack dynamic objects. */
2423 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2424 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2425 (current_function_outgoing_args_size \
2426 + REG_PARM_STACK_SPACE (FNDECL) + (STACK_POINTER_OFFSET))
2429 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2430 (current_function_outgoing_args_size + (STACK_POINTER_OFFSET))
2434 #define STACK_DYNAMIC_OFFSET(FNDECL) STACK_POINTER_OFFSET
2438 /* Pass through the INSNS of function FNDECL and convert virtual register
2439 references to hard register references. */
2442 instantiate_virtual_regs (fndecl, insns)
2448 /* Compute the offsets to use for this function. */
2449 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
2450 var_offset = STARTING_FRAME_OFFSET;
2451 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
2452 out_arg_offset = STACK_POINTER_OFFSET;
2454 /* Scan all variables and parameters of this function. For each that is
2455 in memory, instantiate all virtual registers if the result is a valid
2456 address. If not, we do it later. That will handle most uses of virtual
2457 regs on many machines. */
2458 instantiate_decls (fndecl, 1);
2460 /* Initialize recognition, indicating that volatile is OK. */
2463 /* Scan through all the insns, instantiating every virtual register still
2465 for (insn = insns; insn; insn = NEXT_INSN (insn))
2466 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
2467 || GET_CODE (insn) == CALL_INSN)
2469 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
2470 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
2473 /* Now instantiate the remaining register equivalences for debugging info.
2474 These will not be valid addresses. */
2475 instantiate_decls (fndecl, 0);
2477 /* Indicate that, from now on, assign_stack_local should use
2478 frame_pointer_rtx. */
2479 virtuals_instantiated = 1;
2482 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
2483 all virtual registers in their DECL_RTL's.
2485 If VALID_ONLY, do this only if the resulting address is still valid.
2486 Otherwise, always do it. */
2489 instantiate_decls (fndecl, valid_only)
2495 if (DECL_INLINE (fndecl) || DECL_DEFER_OUTPUT (fndecl))
2496 /* When compiling an inline function, the obstack used for
2497 rtl allocation is the maybepermanent_obstack. Calling
2498 `resume_temporary_allocation' switches us back to that
2499 obstack while we process this function's parameters. */
2500 resume_temporary_allocation ();
2502 /* Process all parameters of the function. */
2503 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
2505 instantiate_decl (DECL_RTL (decl), int_size_in_bytes (TREE_TYPE (decl)),
2507 instantiate_decl (DECL_INCOMING_RTL (decl),
2508 int_size_in_bytes (TREE_TYPE (decl)), valid_only);
2511 /* Now process all variables defined in the function or its subblocks. */
2512 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
2514 if (DECL_INLINE (fndecl) || DECL_DEFER_OUTPUT (fndecl))
2516 /* Save all rtl allocated for this function by raising the
2517 high-water mark on the maybepermanent_obstack. */
2519 /* All further rtl allocation is now done in the current_obstack. */
2520 rtl_in_current_obstack ();
2524 /* Subroutine of instantiate_decls: Process all decls in the given
2525 BLOCK node and all its subblocks. */
2528 instantiate_decls_1 (let, valid_only)
2534 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
2535 instantiate_decl (DECL_RTL (t), int_size_in_bytes (TREE_TYPE (t)),
2538 /* Process all subblocks. */
2539 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
2540 instantiate_decls_1 (t, valid_only);
2543 /* Subroutine of the preceding procedures: Given RTL representing a
2544 decl and the size of the object, do any instantiation required.
2546 If VALID_ONLY is non-zero, it means that the RTL should only be
2547 changed if the new address is valid. */
2550 instantiate_decl (x, size, valid_only)
2555 enum machine_mode mode;
2558 /* If this is not a MEM, no need to do anything. Similarly if the
2559 address is a constant or a register that is not a virtual register. */
2561 if (x == 0 || GET_CODE (x) != MEM)
2565 if (CONSTANT_P (addr)
2566 || (GET_CODE (addr) == REG
2567 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
2568 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
2571 /* If we should only do this if the address is valid, copy the address.
2572 We need to do this so we can undo any changes that might make the
2573 address invalid. This copy is unfortunate, but probably can't be
2577 addr = copy_rtx (addr);
2579 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
2584 /* Now verify that the resulting address is valid for every integer or
2585 floating-point mode up to and including SIZE bytes long. We do this
2586 since the object might be accessed in any mode and frame addresses
2589 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
2590 mode != VOIDmode && GET_MODE_SIZE (mode) <= size;
2591 mode = GET_MODE_WIDER_MODE (mode))
2592 if (! memory_address_p (mode, addr))
2595 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
2596 mode != VOIDmode && GET_MODE_SIZE (mode) <= size;
2597 mode = GET_MODE_WIDER_MODE (mode))
2598 if (! memory_address_p (mode, addr))
2601 /* Otherwise, put back the address, now that we have updated it and we
2602 know it is valid. */
2607 /* Given a pointer to a piece of rtx and an optional pointer to the
2608 containing object, instantiate any virtual registers present in it.
2610 If EXTRA_INSNS, we always do the replacement and generate
2611 any extra insns before OBJECT. If it zero, we do nothing if replacement
2614 Return 1 if we either had nothing to do or if we were able to do the
2615 needed replacement. Return 0 otherwise; we only return zero if
2616 EXTRA_INSNS is zero.
2618 We first try some simple transformations to avoid the creation of extra
2622 instantiate_virtual_regs_1 (loc, object, extra_insns)
2636 /* Re-start here to avoid recursion in common cases. */
2643 code = GET_CODE (x);
2645 /* Check for some special cases. */
2662 /* We are allowed to set the virtual registers. This means that
2663 that the actual register should receive the source minus the
2664 appropriate offset. This is used, for example, in the handling
2665 of non-local gotos. */
2666 if (SET_DEST (x) == virtual_incoming_args_rtx)
2667 new = arg_pointer_rtx, offset = - in_arg_offset;
2668 else if (SET_DEST (x) == virtual_stack_vars_rtx)
2669 new = frame_pointer_rtx, offset = - var_offset;
2670 else if (SET_DEST (x) == virtual_stack_dynamic_rtx)
2671 new = stack_pointer_rtx, offset = - dynamic_offset;
2672 else if (SET_DEST (x) == virtual_outgoing_args_rtx)
2673 new = stack_pointer_rtx, offset = - out_arg_offset;
2677 /* The only valid sources here are PLUS or REG. Just do
2678 the simplest possible thing to handle them. */
2679 if (GET_CODE (SET_SRC (x)) != REG
2680 && GET_CODE (SET_SRC (x)) != PLUS)
2684 if (GET_CODE (SET_SRC (x)) != REG)
2685 temp = force_operand (SET_SRC (x), NULL_RTX);
2688 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
2692 emit_insns_before (seq, object);
2695 if (!validate_change (object, &SET_SRC (x), temp, 0)
2702 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
2707 /* Handle special case of virtual register plus constant. */
2708 if (CONSTANT_P (XEXP (x, 1)))
2710 rtx old, new_offset;
2712 /* Check for (plus (plus VIRT foo) (const_int)) first. */
2713 if (GET_CODE (XEXP (x, 0)) == PLUS)
2715 rtx inner = XEXP (XEXP (x, 0), 0);
2717 if (inner == virtual_incoming_args_rtx)
2718 new = arg_pointer_rtx, offset = in_arg_offset;
2719 else if (inner == virtual_stack_vars_rtx)
2720 new = frame_pointer_rtx, offset = var_offset;
2721 else if (inner == virtual_stack_dynamic_rtx)
2722 new = stack_pointer_rtx, offset = dynamic_offset;
2723 else if (inner == virtual_outgoing_args_rtx)
2724 new = stack_pointer_rtx, offset = out_arg_offset;
2731 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
2733 new = gen_rtx (PLUS, Pmode, new, XEXP (XEXP (x, 0), 1));
2736 else if (XEXP (x, 0) == virtual_incoming_args_rtx)
2737 new = arg_pointer_rtx, offset = in_arg_offset;
2738 else if (XEXP (x, 0) == virtual_stack_vars_rtx)
2739 new = frame_pointer_rtx, offset = var_offset;
2740 else if (XEXP (x, 0) == virtual_stack_dynamic_rtx)
2741 new = stack_pointer_rtx, offset = dynamic_offset;
2742 else if (XEXP (x, 0) == virtual_outgoing_args_rtx)
2743 new = stack_pointer_rtx, offset = out_arg_offset;
2746 /* We know the second operand is a constant. Unless the
2747 first operand is a REG (which has been already checked),
2748 it needs to be checked. */
2749 if (GET_CODE (XEXP (x, 0)) != REG)
2757 new_offset = plus_constant (XEXP (x, 1), offset);
2759 /* If the new constant is zero, try to replace the sum with just
2761 if (new_offset == const0_rtx
2762 && validate_change (object, loc, new, 0))
2765 /* Next try to replace the register and new offset.
2766 There are two changes to validate here and we can't assume that
2767 in the case of old offset equals new just changing the register
2768 will yield a valid insn. In the interests of a little efficiency,
2769 however, we only call validate change once (we don't queue up the
2770 changes and then call apply_change_group). */
2774 ? ! validate_change (object, &XEXP (x, 0), new, 0)
2775 : (XEXP (x, 0) = new,
2776 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
2784 /* Otherwise copy the new constant into a register and replace
2785 constant with that register. */
2786 temp = gen_reg_rtx (Pmode);
2788 if (validate_change (object, &XEXP (x, 1), temp, 0))
2789 emit_insn_before (gen_move_insn (temp, new_offset), object);
2792 /* If that didn't work, replace this expression with a
2793 register containing the sum. */
2796 new = gen_rtx (PLUS, Pmode, new, new_offset);
2799 temp = force_operand (new, NULL_RTX);
2803 emit_insns_before (seq, object);
2804 if (! validate_change (object, loc, temp, 0)
2805 && ! validate_replace_rtx (x, temp, object))
2813 /* Fall through to generic two-operand expression case. */
2819 case DIV: case UDIV:
2820 case MOD: case UMOD:
2821 case AND: case IOR: case XOR:
2822 case ROTATERT: case ROTATE:
2823 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
2825 case GE: case GT: case GEU: case GTU:
2826 case LE: case LT: case LEU: case LTU:
2827 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
2828 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
2833 /* Most cases of MEM that convert to valid addresses have already been
2834 handled by our scan of regno_reg_rtx. The only special handling we
2835 need here is to make a copy of the rtx to ensure it isn't being
2836 shared if we have to change it to a pseudo.
2838 If the rtx is a simple reference to an address via a virtual register,
2839 it can potentially be shared. In such cases, first try to make it
2840 a valid address, which can also be shared. Otherwise, copy it and
2843 First check for common cases that need no processing. These are
2844 usually due to instantiation already being done on a previous instance
2848 if (CONSTANT_ADDRESS_P (temp)
2849 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
2850 || temp == arg_pointer_rtx
2852 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2853 || temp == hard_frame_pointer_rtx
2855 || temp == frame_pointer_rtx)
2858 if (GET_CODE (temp) == PLUS
2859 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
2860 && (XEXP (temp, 0) == frame_pointer_rtx
2861 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2862 || XEXP (temp, 0) == hard_frame_pointer_rtx
2864 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
2865 || XEXP (temp, 0) == arg_pointer_rtx
2870 if (temp == virtual_stack_vars_rtx
2871 || temp == virtual_incoming_args_rtx
2872 || (GET_CODE (temp) == PLUS
2873 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
2874 && (XEXP (temp, 0) == virtual_stack_vars_rtx
2875 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
2877 /* This MEM may be shared. If the substitution can be done without
2878 the need to generate new pseudos, we want to do it in place
2879 so all copies of the shared rtx benefit. The call below will
2880 only make substitutions if the resulting address is still
2883 Note that we cannot pass X as the object in the recursive call
2884 since the insn being processed may not allow all valid
2885 addresses. However, if we were not passed on object, we can
2886 only modify X without copying it if X will have a valid
2889 ??? Also note that this can still lose if OBJECT is an insn that
2890 has less restrictions on an address that some other insn.
2891 In that case, we will modify the shared address. This case
2892 doesn't seem very likely, though. */
2894 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
2895 object ? object : x, 0))
2898 /* Otherwise make a copy and process that copy. We copy the entire
2899 RTL expression since it might be a PLUS which could also be
2901 *loc = x = copy_rtx (x);
2904 /* Fall through to generic unary operation case. */
2908 case STRICT_LOW_PART:
2910 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
2911 case SIGN_EXTEND: case ZERO_EXTEND:
2912 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
2913 case FLOAT: case FIX:
2914 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
2918 /* These case either have just one operand or we know that we need not
2919 check the rest of the operands. */
2924 /* Try to replace with a PLUS. If that doesn't work, compute the sum
2925 in front of this insn and substitute the temporary. */
2926 if (x == virtual_incoming_args_rtx)
2927 new = arg_pointer_rtx, offset = in_arg_offset;
2928 else if (x == virtual_stack_vars_rtx)
2929 new = frame_pointer_rtx, offset = var_offset;
2930 else if (x == virtual_stack_dynamic_rtx)
2931 new = stack_pointer_rtx, offset = dynamic_offset;
2932 else if (x == virtual_outgoing_args_rtx)
2933 new = stack_pointer_rtx, offset = out_arg_offset;
2937 temp = plus_constant (new, offset);
2938 if (!validate_change (object, loc, temp, 0))
2944 temp = force_operand (temp, NULL_RTX);
2948 emit_insns_before (seq, object);
2949 if (! validate_change (object, loc, temp, 0)
2950 && ! validate_replace_rtx (x, temp, object))
2958 /* Scan all subexpressions. */
2959 fmt = GET_RTX_FORMAT (code);
2960 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
2963 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
2966 else if (*fmt == 'E')
2967 for (j = 0; j < XVECLEN (x, i); j++)
2968 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
2975 /* Optimization: assuming this function does not receive nonlocal gotos,
2976 delete the handlers for such, as well as the insns to establish
2977 and disestablish them. */
2983 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
2985 /* Delete the handler by turning off the flag that would
2986 prevent jump_optimize from deleting it.
2987 Also permit deletion of the nonlocal labels themselves
2988 if nothing local refers to them. */
2989 if (GET_CODE (insn) == CODE_LABEL)
2993 LABEL_PRESERVE_P (insn) = 0;
2995 /* Remove it from the nonlocal_label list, to avoid confusing
2997 for (t = nonlocal_labels, last_t = 0; t;
2998 last_t = t, t = TREE_CHAIN (t))
2999 if (DECL_RTL (TREE_VALUE (t)) == insn)
3004 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
3006 TREE_CHAIN (last_t) = TREE_CHAIN (t);
3009 if (GET_CODE (insn) == INSN
3010 && ((nonlocal_goto_handler_slot != 0
3011 && reg_mentioned_p (nonlocal_goto_handler_slot, PATTERN (insn)))
3012 || (nonlocal_goto_stack_level != 0
3013 && reg_mentioned_p (nonlocal_goto_stack_level,
3019 /* Return a list (chain of EXPR_LIST nodes) for the nonlocal labels
3020 of the current function. */
3023 nonlocal_label_rtx_list ()
3028 for (t = nonlocal_labels; t; t = TREE_CHAIN (t))
3029 x = gen_rtx (EXPR_LIST, VOIDmode, label_rtx (TREE_VALUE (t)), x);
3034 /* Output a USE for any register use in RTL.
3035 This is used with -noreg to mark the extent of lifespan
3036 of any registers used in a user-visible variable's DECL_RTL. */
3042 if (GET_CODE (rtl) == REG)
3043 /* This is a register variable. */
3044 emit_insn (gen_rtx (USE, VOIDmode, rtl));
3045 else if (GET_CODE (rtl) == MEM
3046 && GET_CODE (XEXP (rtl, 0)) == REG
3047 && (REGNO (XEXP (rtl, 0)) < FIRST_VIRTUAL_REGISTER
3048 || REGNO (XEXP (rtl, 0)) > LAST_VIRTUAL_REGISTER)
3049 && XEXP (rtl, 0) != current_function_internal_arg_pointer)
3050 /* This is a variable-sized structure. */
3051 emit_insn (gen_rtx (USE, VOIDmode, XEXP (rtl, 0)));
3054 /* Like use_variable except that it outputs the USEs after INSN
3055 instead of at the end of the insn-chain. */
3058 use_variable_after (rtl, insn)
3061 if (GET_CODE (rtl) == REG)
3062 /* This is a register variable. */
3063 emit_insn_after (gen_rtx (USE, VOIDmode, rtl), insn);
3064 else if (GET_CODE (rtl) == MEM
3065 && GET_CODE (XEXP (rtl, 0)) == REG
3066 && (REGNO (XEXP (rtl, 0)) < FIRST_VIRTUAL_REGISTER
3067 || REGNO (XEXP (rtl, 0)) > LAST_VIRTUAL_REGISTER)
3068 && XEXP (rtl, 0) != current_function_internal_arg_pointer)
3069 /* This is a variable-sized structure. */
3070 emit_insn_after (gen_rtx (USE, VOIDmode, XEXP (rtl, 0)), insn);
3076 return max_parm_reg;
3079 /* Return the first insn following those generated by `assign_parms'. */
3082 get_first_nonparm_insn ()
3085 return NEXT_INSN (last_parm_insn);
3086 return get_insns ();
3089 /* Return the first NOTE_INSN_BLOCK_BEG note in the function.
3090 Crash if there is none. */
3093 get_first_block_beg ()
3095 register rtx searcher;
3096 register rtx insn = get_first_nonparm_insn ();
3098 for (searcher = insn; searcher; searcher = NEXT_INSN (searcher))
3099 if (GET_CODE (searcher) == NOTE
3100 && NOTE_LINE_NUMBER (searcher) == NOTE_INSN_BLOCK_BEG)
3103 abort (); /* Invalid call to this function. (See comments above.) */
3107 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
3108 This means a type for which function calls must pass an address to the
3109 function or get an address back from the function.
3110 EXP may be a type node or an expression (whose type is tested). */
3113 aggregate_value_p (exp)
3116 int i, regno, nregs;
3119 if (TREE_CODE_CLASS (TREE_CODE (exp)) == 't')
3122 type = TREE_TYPE (exp);
3124 if (RETURN_IN_MEMORY (type))
3126 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
3128 /* Make sure we have suitable call-clobbered regs to return
3129 the value in; if not, we must return it in memory. */
3130 reg = hard_function_value (type, 0);
3131 regno = REGNO (reg);
3132 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
3133 for (i = 0; i < nregs; i++)
3134 if (! call_used_regs[regno + i])
3139 /* Assign RTL expressions to the function's parameters.
3140 This may involve copying them into registers and using
3141 those registers as the RTL for them.
3143 If SECOND_TIME is non-zero it means that this function is being
3144 called a second time. This is done by integrate.c when a function's
3145 compilation is deferred. We need to come back here in case the
3146 FUNCTION_ARG macro computes items needed for the rest of the compilation
3147 (such as changing which registers are fixed or caller-saved). But suppress
3148 writing any insns or setting DECL_RTL of anything in this case. */
3151 assign_parms (fndecl, second_time)
3156 register rtx entry_parm = 0;
3157 register rtx stack_parm = 0;
3158 CUMULATIVE_ARGS args_so_far;
3159 enum machine_mode promoted_mode, passed_mode;
3160 enum machine_mode nominal_mode, promoted_nominal_mode;
3162 /* Total space needed so far for args on the stack,
3163 given as a constant and a tree-expression. */
3164 struct args_size stack_args_size;
3165 tree fntype = TREE_TYPE (fndecl);
3166 tree fnargs = DECL_ARGUMENTS (fndecl);
3167 /* This is used for the arg pointer when referring to stack args. */
3168 rtx internal_arg_pointer;
3169 /* This is a dummy PARM_DECL that we used for the function result if
3170 the function returns a structure. */
3171 tree function_result_decl = 0;
3172 int nparmregs = list_length (fnargs) + LAST_VIRTUAL_REGISTER + 1;
3173 int varargs_setup = 0;
3174 rtx conversion_insns = 0;
3175 /* FUNCTION_ARG may look at this variable. Since this is not
3176 expanding a call it will always be zero in this function. */
3177 int current_call_is_indirect = 0;
3179 /* Nonzero if the last arg is named `__builtin_va_alist',
3180 which is used on some machines for old-fashioned non-ANSI varargs.h;
3181 this should be stuck onto the stack as if it had arrived there. */
3183 = (current_function_varargs
3185 && (parm = tree_last (fnargs)) != 0
3187 && (! strcmp (IDENTIFIER_POINTER (DECL_NAME (parm)),
3188 "__builtin_va_alist")));
3190 /* Nonzero if function takes extra anonymous args.
3191 This means the last named arg must be on the stack
3192 right before the anonymous ones. */
3194 = (TYPE_ARG_TYPES (fntype) != 0
3195 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
3196 != void_type_node));
3198 current_function_stdarg = stdarg;
3200 /* If the reg that the virtual arg pointer will be translated into is
3201 not a fixed reg or is the stack pointer, make a copy of the virtual
3202 arg pointer, and address parms via the copy. The frame pointer is
3203 considered fixed even though it is not marked as such.
3205 The second time through, simply use ap to avoid generating rtx. */
3207 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
3208 || ! (fixed_regs[ARG_POINTER_REGNUM]
3209 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM))
3211 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
3213 internal_arg_pointer = virtual_incoming_args_rtx;
3214 current_function_internal_arg_pointer = internal_arg_pointer;
3216 stack_args_size.constant = 0;
3217 stack_args_size.var = 0;
3219 /* If struct value address is treated as the first argument, make it so. */
3220 if (aggregate_value_p (DECL_RESULT (fndecl))
3221 && ! current_function_returns_pcc_struct
3222 && struct_value_incoming_rtx == 0)
3224 tree type = build_pointer_type (fntype);
3226 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
3228 DECL_ARG_TYPE (function_result_decl) = type;
3229 TREE_CHAIN (function_result_decl) = fnargs;
3230 fnargs = function_result_decl;
3233 parm_reg_stack_loc = (rtx *) oballoc (nparmregs * sizeof (rtx));
3234 bzero ((char *) parm_reg_stack_loc, nparmregs * sizeof (rtx));
3236 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
3237 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
3239 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX);
3242 /* We haven't yet found an argument that we must push and pretend the
3244 current_function_pretend_args_size = 0;
3246 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
3248 int aggregate = AGGREGATE_TYPE_P (TREE_TYPE (parm));
3249 struct args_size stack_offset;
3250 struct args_size arg_size;
3251 int passed_pointer = 0;
3252 int did_conversion = 0;
3253 tree passed_type = DECL_ARG_TYPE (parm);
3254 tree nominal_type = TREE_TYPE (parm);
3256 /* Set LAST_NAMED if this is last named arg before some
3257 anonymous args. We treat it as if it were anonymous too. */
3258 int last_named = ((TREE_CHAIN (parm) == 0
3259 || DECL_NAME (TREE_CHAIN (parm)) == 0)
3260 && (stdarg || current_function_varargs));
3262 if (TREE_TYPE (parm) == error_mark_node
3263 /* This can happen after weird syntax errors
3264 or if an enum type is defined among the parms. */
3265 || TREE_CODE (parm) != PARM_DECL
3266 || passed_type == NULL)
3268 DECL_INCOMING_RTL (parm) = DECL_RTL (parm) = gen_rtx (MEM, BLKmode,
3270 TREE_USED (parm) = 1;
3274 /* For varargs.h function, save info about regs and stack space
3275 used by the individual args, not including the va_alist arg. */
3276 if (hide_last_arg && last_named)
3277 current_function_args_info = args_so_far;
3279 /* Find mode of arg as it is passed, and mode of arg
3280 as it should be during execution of this function. */
3281 passed_mode = TYPE_MODE (passed_type);
3282 nominal_mode = TYPE_MODE (nominal_type);
3284 /* If the parm's mode is VOID, its value doesn't matter,
3285 and avoid the usual things like emit_move_insn that could crash. */
3286 if (nominal_mode == VOIDmode)
3288 DECL_INCOMING_RTL (parm) = DECL_RTL (parm) = const0_rtx;
3292 /* If the parm is to be passed as a transparent union, use the
3293 type of the first field for the tests below. We have already
3294 verified that the modes are the same. */
3295 if (DECL_TRANSPARENT_UNION (parm)
3296 || TYPE_TRANSPARENT_UNION (passed_type))
3297 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
3299 /* See if this arg was passed by invisible reference. It is if
3300 it is an object whose size depends on the contents of the
3301 object itself or if the machine requires these objects be passed
3304 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
3305 && contains_placeholder_p (TYPE_SIZE (passed_type)))
3306 || TREE_ADDRESSABLE (passed_type)
3307 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3308 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
3309 passed_type, ! last_named)
3313 passed_type = nominal_type = build_pointer_type (passed_type);
3315 passed_mode = nominal_mode = Pmode;
3318 promoted_mode = passed_mode;
3320 #ifdef PROMOTE_FUNCTION_ARGS
3321 /* Compute the mode in which the arg is actually extended to. */
3322 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
3325 /* Let machine desc say which reg (if any) the parm arrives in.
3326 0 means it arrives on the stack. */
3327 #ifdef FUNCTION_INCOMING_ARG
3328 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
3329 passed_type, ! last_named);
3331 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
3332 passed_type, ! last_named);
3335 if (entry_parm == 0)
3336 promoted_mode = passed_mode;
3338 #ifdef SETUP_INCOMING_VARARGS
3339 /* If this is the last named parameter, do any required setup for
3340 varargs or stdargs. We need to know about the case of this being an
3341 addressable type, in which case we skip the registers it
3342 would have arrived in.
3344 For stdargs, LAST_NAMED will be set for two parameters, the one that
3345 is actually the last named, and the dummy parameter. We only
3346 want to do this action once.
3348 Also, indicate when RTL generation is to be suppressed. */
3349 if (last_named && !varargs_setup)
3351 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
3352 current_function_pretend_args_size,
3358 /* Determine parm's home in the stack,
3359 in case it arrives in the stack or we should pretend it did.
3361 Compute the stack position and rtx where the argument arrives
3364 There is one complexity here: If this was a parameter that would
3365 have been passed in registers, but wasn't only because it is
3366 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
3367 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
3368 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
3369 0 as it was the previous time. */
3371 locate_and_pad_parm (promoted_mode, passed_type,
3372 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3375 #ifdef FUNCTION_INCOMING_ARG
3376 FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
3379 || varargs_setup)) != 0,
3381 FUNCTION_ARG (args_so_far, promoted_mode,
3383 ! last_named || varargs_setup) != 0,
3386 fndecl, &stack_args_size, &stack_offset, &arg_size);
3390 rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
3392 if (offset_rtx == const0_rtx)
3393 stack_parm = gen_rtx (MEM, promoted_mode, internal_arg_pointer);
3395 stack_parm = gen_rtx (MEM, promoted_mode,
3396 gen_rtx (PLUS, Pmode,
3397 internal_arg_pointer, offset_rtx));
3399 /* If this is a memory ref that contains aggregate components,
3400 mark it as such for cse and loop optimize. */
3401 MEM_IN_STRUCT_P (stack_parm) = aggregate;
3404 /* If this parameter was passed both in registers and in the stack,
3405 use the copy on the stack. */
3406 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
3409 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3410 /* If this parm was passed part in regs and part in memory,
3411 pretend it arrived entirely in memory
3412 by pushing the register-part onto the stack.
3414 In the special case of a DImode or DFmode that is split,
3415 we could put it together in a pseudoreg directly,
3416 but for now that's not worth bothering with. */
3420 int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
3421 passed_type, ! last_named);
3425 current_function_pretend_args_size
3426 = (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
3427 / (PARM_BOUNDARY / BITS_PER_UNIT)
3428 * (PARM_BOUNDARY / BITS_PER_UNIT));
3431 move_block_from_reg (REGNO (entry_parm),
3432 validize_mem (stack_parm), nregs,
3433 int_size_in_bytes (TREE_TYPE (parm)));
3434 entry_parm = stack_parm;
3439 /* If we didn't decide this parm came in a register,
3440 by default it came on the stack. */
3441 if (entry_parm == 0)
3442 entry_parm = stack_parm;
3444 /* Record permanently how this parm was passed. */
3446 DECL_INCOMING_RTL (parm) = entry_parm;
3448 /* If there is actually space on the stack for this parm,
3449 count it in stack_args_size; otherwise set stack_parm to 0
3450 to indicate there is no preallocated stack slot for the parm. */
3452 if (entry_parm == stack_parm
3453 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
3454 /* On some machines, even if a parm value arrives in a register
3455 there is still an (uninitialized) stack slot allocated for it.
3457 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
3458 whether this parameter already has a stack slot allocated,
3459 because an arg block exists only if current_function_args_size
3460 is larger than some threshold, and we haven't calculated that
3461 yet. So, for now, we just assume that stack slots never exist
3463 || REG_PARM_STACK_SPACE (fndecl) > 0
3467 stack_args_size.constant += arg_size.constant;
3469 ADD_PARM_SIZE (stack_args_size, arg_size.var);
3472 /* No stack slot was pushed for this parm. */
3475 /* Update info on where next arg arrives in registers. */
3477 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
3478 passed_type, ! last_named);
3480 /* If this is our second time through, we are done with this parm. */
3484 /* If we can't trust the parm stack slot to be aligned enough
3485 for its ultimate type, don't use that slot after entry.
3486 We'll make another stack slot, if we need one. */
3488 int thisparm_boundary
3489 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
3491 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
3495 /* If parm was passed in memory, and we need to convert it on entry,
3496 don't store it back in that same slot. */
3498 && nominal_mode != BLKmode && nominal_mode != passed_mode)
3502 /* Now adjust STACK_PARM to the mode and precise location
3503 where this parameter should live during execution,
3504 if we discover that it must live in the stack during execution.
3505 To make debuggers happier on big-endian machines, we store
3506 the value in the last bytes of the space available. */
3508 if (nominal_mode != BLKmode && nominal_mode != passed_mode
3513 if (BYTES_BIG_ENDIAN
3514 && GET_MODE_SIZE (nominal_mode) < UNITS_PER_WORD)
3515 stack_offset.constant += (GET_MODE_SIZE (passed_mode)
3516 - GET_MODE_SIZE (nominal_mode));
3518 offset_rtx = ARGS_SIZE_RTX (stack_offset);
3519 if (offset_rtx == const0_rtx)
3520 stack_parm = gen_rtx (MEM, nominal_mode, internal_arg_pointer);
3522 stack_parm = gen_rtx (MEM, nominal_mode,
3523 gen_rtx (PLUS, Pmode,
3524 internal_arg_pointer, offset_rtx));
3526 /* If this is a memory ref that contains aggregate components,
3527 mark it as such for cse and loop optimize. */
3528 MEM_IN_STRUCT_P (stack_parm) = aggregate;
3533 /* We need this "use" info, because the gcc-register->stack-register
3534 converter in reg-stack.c needs to know which registers are active
3535 at the start of the function call. The actual parameter loading
3536 instructions are not always available then anymore, since they might
3537 have been optimised away. */
3539 if (GET_CODE (entry_parm) == REG && !(hide_last_arg && last_named))
3540 emit_insn (gen_rtx (USE, GET_MODE (entry_parm), entry_parm));
3543 /* ENTRY_PARM is an RTX for the parameter as it arrives,
3544 in the mode in which it arrives.
3545 STACK_PARM is an RTX for a stack slot where the parameter can live
3546 during the function (in case we want to put it there).
3547 STACK_PARM is 0 if no stack slot was pushed for it.
3549 Now output code if necessary to convert ENTRY_PARM to
3550 the type in which this function declares it,
3551 and store that result in an appropriate place,
3552 which may be a pseudo reg, may be STACK_PARM,
3553 or may be a local stack slot if STACK_PARM is 0.
3555 Set DECL_RTL to that place. */
3557 if (nominal_mode == BLKmode)
3559 /* If a BLKmode arrives in registers, copy it to a stack slot. */
3560 if (GET_CODE (entry_parm) == REG)
3563 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
3566 /* Note that we will be storing an integral number of words.
3567 So we have to be careful to ensure that we allocate an
3568 integral number of words. We do this below in the
3569 assign_stack_local if space was not allocated in the argument
3570 list. If it was, this will not work if PARM_BOUNDARY is not
3571 a multiple of BITS_PER_WORD. It isn't clear how to fix this
3572 if it becomes a problem. */
3574 if (stack_parm == 0)
3577 = assign_stack_local (GET_MODE (entry_parm),
3580 /* If this is a memory ref that contains aggregate
3581 components, mark it as such for cse and loop optimize. */
3582 MEM_IN_STRUCT_P (stack_parm) = aggregate;
3585 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
3588 if (TREE_READONLY (parm))
3589 RTX_UNCHANGING_P (stack_parm) = 1;
3591 move_block_from_reg (REGNO (entry_parm),
3592 validize_mem (stack_parm),
3593 size_stored / UNITS_PER_WORD,
3594 int_size_in_bytes (TREE_TYPE (parm)));
3596 DECL_RTL (parm) = stack_parm;
3598 else if (! ((obey_regdecls && ! DECL_REGISTER (parm)
3599 && ! DECL_INLINE (fndecl))
3600 /* layout_decl may set this. */
3601 || TREE_ADDRESSABLE (parm)
3602 || TREE_SIDE_EFFECTS (parm)
3603 /* If -ffloat-store specified, don't put explicit
3604 float variables into registers. */
3605 || (flag_float_store
3606 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
3607 /* Always assign pseudo to structure return or item passed
3608 by invisible reference. */
3609 || passed_pointer || parm == function_result_decl)
3611 /* Store the parm in a pseudoregister during the function, but we
3612 may need to do it in a wider mode. */
3614 register rtx parmreg;
3615 int regno, regnoi, regnor;
3617 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
3619 promoted_nominal_mode
3620 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
3622 parmreg = gen_reg_rtx (promoted_nominal_mode);
3623 REG_USERVAR_P (parmreg) = 1;
3625 /* If this was an item that we received a pointer to, set DECL_RTL
3630 = gen_rtx (MEM, TYPE_MODE (TREE_TYPE (passed_type)), parmreg);
3631 MEM_IN_STRUCT_P (DECL_RTL (parm)) = aggregate;
3634 DECL_RTL (parm) = parmreg;
3636 /* Copy the value into the register. */
3637 if (nominal_mode != passed_mode
3638 || promoted_nominal_mode != promoted_mode)
3640 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
3641 mode, by the caller. We now have to convert it to
3642 NOMINAL_MODE, if different. However, PARMREG may be in
3643 a diffent mode than NOMINAL_MODE if it is being stored
3646 If ENTRY_PARM is a hard register, it might be in a register
3647 not valid for operating in its mode (e.g., an odd-numbered
3648 register for a DFmode). In that case, moves are the only
3649 thing valid, so we can't do a convert from there. This
3650 occurs when the calling sequence allow such misaligned
3653 In addition, the conversion may involve a call, which could
3654 clobber parameters which haven't been copied to pseudo
3655 registers yet. Therefore, we must first copy the parm to
3656 a pseudo reg here, and save the conversion until after all
3657 parameters have been moved. */
3659 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
3661 emit_move_insn (tempreg, validize_mem (entry_parm));
3663 push_to_sequence (conversion_insns);
3664 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
3666 expand_assignment (parm,
3667 make_tree (nominal_type, tempreg), 0, 0);
3668 conversion_insns = get_insns ();
3673 emit_move_insn (parmreg, validize_mem (entry_parm));
3675 /* If we were passed a pointer but the actual value
3676 can safely live in a register, put it in one. */
3677 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
3678 && ! ((obey_regdecls && ! DECL_REGISTER (parm)
3679 && ! DECL_INLINE (fndecl))
3680 /* layout_decl may set this. */
3681 || TREE_ADDRESSABLE (parm)
3682 || TREE_SIDE_EFFECTS (parm)
3683 /* If -ffloat-store specified, don't put explicit
3684 float variables into registers. */
3685 || (flag_float_store
3686 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE)))
3688 /* We can't use nominal_mode, because it will have been set to
3689 Pmode above. We must use the actual mode of the parm. */
3690 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
3691 REG_USERVAR_P (parmreg) = 1;
3692 emit_move_insn (parmreg, DECL_RTL (parm));
3693 DECL_RTL (parm) = parmreg;
3694 /* STACK_PARM is the pointer, not the parm, and PARMREG is
3698 #ifdef FUNCTION_ARG_CALLEE_COPIES
3699 /* If we are passed an arg by reference and it is our responsibility
3700 to make a copy, do it now.
3701 PASSED_TYPE and PASSED mode now refer to the pointer, not the
3702 original argument, so we must recreate them in the call to
3703 FUNCTION_ARG_CALLEE_COPIES. */
3704 /* ??? Later add code to handle the case that if the argument isn't
3705 modified, don't do the copy. */
3707 else if (passed_pointer
3708 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
3709 TYPE_MODE (DECL_ARG_TYPE (parm)),
3710 DECL_ARG_TYPE (parm),
3712 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
3715 tree type = DECL_ARG_TYPE (parm);
3717 /* This sequence may involve a library call perhaps clobbering
3718 registers that haven't been copied to pseudos yet. */
3720 push_to_sequence (conversion_insns);
3722 if (TYPE_SIZE (type) == 0
3723 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
3724 /* This is a variable sized object. */
3725 copy = gen_rtx (MEM, BLKmode,
3726 allocate_dynamic_stack_space
3727 (expr_size (parm), NULL_RTX,
3728 TYPE_ALIGN (type)));
3730 copy = assign_stack_temp (TYPE_MODE (type),
3731 int_size_in_bytes (type), 1);
3732 MEM_IN_STRUCT_P (copy) = AGGREGATE_TYPE_P (type);
3734 store_expr (parm, copy, 0);
3735 emit_move_insn (parmreg, XEXP (copy, 0));
3736 conversion_insns = get_insns ();
3740 #endif /* FUNCTION_ARG_CALLEE_COPIES */
3742 /* In any case, record the parm's desired stack location
3743 in case we later discover it must live in the stack.
3745 If it is a COMPLEX value, store the stack location for both
3748 if (GET_CODE (parmreg) == CONCAT)
3749 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
3751 regno = REGNO (parmreg);
3753 if (regno >= nparmregs)
3756 int old_nparmregs = nparmregs;
3758 nparmregs = regno + 5;
3759 new = (rtx *) oballoc (nparmregs * sizeof (rtx));
3760 bcopy ((char *) parm_reg_stack_loc, (char *) new,
3761 old_nparmregs * sizeof (rtx));
3762 bzero ((char *) (new + old_nparmregs),
3763 (nparmregs - old_nparmregs) * sizeof (rtx));
3764 parm_reg_stack_loc = new;
3767 if (GET_CODE (parmreg) == CONCAT)
3769 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
3771 regnor = REGNO (gen_realpart (submode, parmreg));
3772 regnoi = REGNO (gen_imagpart (submode, parmreg));
3774 if (stack_parm != 0)
3776 parm_reg_stack_loc[regnor]
3777 = gen_realpart (submode, stack_parm);
3778 parm_reg_stack_loc[regnoi]
3779 = gen_imagpart (submode, stack_parm);
3783 parm_reg_stack_loc[regnor] = 0;
3784 parm_reg_stack_loc[regnoi] = 0;
3788 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
3790 /* Mark the register as eliminable if we did no conversion
3791 and it was copied from memory at a fixed offset,
3792 and the arg pointer was not copied to a pseudo-reg.
3793 If the arg pointer is a pseudo reg or the offset formed
3794 an invalid address, such memory-equivalences
3795 as we make here would screw up life analysis for it. */
3796 if (nominal_mode == passed_mode
3798 && GET_CODE (entry_parm) == MEM
3799 && entry_parm == stack_parm
3800 && stack_offset.var == 0
3801 && reg_mentioned_p (virtual_incoming_args_rtx,
3802 XEXP (entry_parm, 0)))
3804 rtx linsn = get_last_insn ();
3806 /* Mark complex types separately. */
3807 if (GET_CODE (parmreg) == CONCAT)
3810 = gen_rtx (EXPR_LIST, REG_EQUIV,
3811 parm_reg_stack_loc[regnoi], REG_NOTES (linsn));
3813 /* Now search backward for where we set the real part. */
3815 && ! reg_referenced_p (parm_reg_stack_loc[regnor],
3817 linsn = prev_nonnote_insn (linsn))
3821 = gen_rtx (EXPR_LIST, REG_EQUIV,
3822 parm_reg_stack_loc[regnor], REG_NOTES (linsn));
3826 = gen_rtx (EXPR_LIST, REG_EQUIV,
3827 entry_parm, REG_NOTES (linsn));
3830 /* For pointer data type, suggest pointer register. */
3831 if (TREE_CODE (TREE_TYPE (parm)) == POINTER_TYPE)
3832 mark_reg_pointer (parmreg);
3836 /* Value must be stored in the stack slot STACK_PARM
3837 during function execution. */
3839 if (promoted_mode != nominal_mode)
3841 /* Conversion is required. */
3842 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
3844 emit_move_insn (tempreg, validize_mem (entry_parm));
3846 push_to_sequence (conversion_insns);
3847 entry_parm = convert_to_mode (nominal_mode, tempreg,
3848 TREE_UNSIGNED (TREE_TYPE (parm)));
3849 conversion_insns = get_insns ();
3854 if (entry_parm != stack_parm)
3856 if (stack_parm == 0)
3859 = assign_stack_local (GET_MODE (entry_parm),
3860 GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
3861 /* If this is a memory ref that contains aggregate components,
3862 mark it as such for cse and loop optimize. */
3863 MEM_IN_STRUCT_P (stack_parm) = aggregate;
3866 if (promoted_mode != nominal_mode)
3868 push_to_sequence (conversion_insns);
3869 emit_move_insn (validize_mem (stack_parm),
3870 validize_mem (entry_parm));
3871 conversion_insns = get_insns ();
3875 emit_move_insn (validize_mem (stack_parm),
3876 validize_mem (entry_parm));
3879 DECL_RTL (parm) = stack_parm;
3882 /* If this "parameter" was the place where we are receiving the
3883 function's incoming structure pointer, set up the result. */
3884 if (parm == function_result_decl)
3886 tree result = DECL_RESULT (fndecl);
3887 tree restype = TREE_TYPE (result);
3890 = gen_rtx (MEM, DECL_MODE (result), DECL_RTL (parm));
3892 MEM_IN_STRUCT_P (DECL_RTL (result)) = AGGREGATE_TYPE_P (restype);
3895 if (TREE_THIS_VOLATILE (parm))
3896 MEM_VOLATILE_P (DECL_RTL (parm)) = 1;
3897 if (TREE_READONLY (parm))
3898 RTX_UNCHANGING_P (DECL_RTL (parm)) = 1;
3901 /* Output all parameter conversion instructions (possibly including calls)
3902 now that all parameters have been copied out of hard registers. */
3903 emit_insns (conversion_insns);
3905 max_parm_reg = max_reg_num ();
3906 last_parm_insn = get_last_insn ();
3908 current_function_args_size = stack_args_size.constant;
3910 /* Adjust function incoming argument size for alignment and
3913 #ifdef REG_PARM_STACK_SPACE
3914 #ifndef MAYBE_REG_PARM_STACK_SPACE
3915 current_function_args_size = MAX (current_function_args_size,
3916 REG_PARM_STACK_SPACE (fndecl));
3920 #ifdef STACK_BOUNDARY
3921 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
3923 current_function_args_size
3924 = ((current_function_args_size + STACK_BYTES - 1)
3925 / STACK_BYTES) * STACK_BYTES;
3928 #ifdef ARGS_GROW_DOWNWARD
3929 current_function_arg_offset_rtx
3930 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
3931 : expand_expr (size_binop (MINUS_EXPR, stack_args_size.var,
3932 size_int (-stack_args_size.constant)),
3933 NULL_RTX, VOIDmode, 0));
3935 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
3938 /* See how many bytes, if any, of its args a function should try to pop
3941 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
3942 current_function_args_size);
3944 /* For stdarg.h function, save info about
3945 regs and stack space used by the named args. */
3948 current_function_args_info = args_so_far;
3950 /* Set the rtx used for the function return value. Put this in its
3951 own variable so any optimizers that need this information don't have
3952 to include tree.h. Do this here so it gets done when an inlined
3953 function gets output. */
3955 current_function_return_rtx = DECL_RTL (DECL_RESULT (fndecl));
3958 /* Indicate whether REGNO is an incoming argument to the current function
3959 that was promoted to a wider mode. If so, return the RTX for the
3960 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
3961 that REGNO is promoted from and whether the promotion was signed or
3964 #ifdef PROMOTE_FUNCTION_ARGS
3967 promoted_input_arg (regno, pmode, punsignedp)
3969 enum machine_mode *pmode;
3974 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
3975 arg = TREE_CHAIN (arg))
3976 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
3977 && REGNO (DECL_INCOMING_RTL (arg)) == regno
3978 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
3980 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
3981 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
3983 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
3984 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
3985 && mode != DECL_MODE (arg))
3987 *pmode = DECL_MODE (arg);
3988 *punsignedp = unsignedp;
3989 return DECL_INCOMING_RTL (arg);
3998 /* Compute the size and offset from the start of the stacked arguments for a
3999 parm passed in mode PASSED_MODE and with type TYPE.
4001 INITIAL_OFFSET_PTR points to the current offset into the stacked
4004 The starting offset and size for this parm are returned in *OFFSET_PTR
4005 and *ARG_SIZE_PTR, respectively.
4007 IN_REGS is non-zero if the argument will be passed in registers. It will
4008 never be set if REG_PARM_STACK_SPACE is not defined.
4010 FNDECL is the function in which the argument was defined.
4012 There are two types of rounding that are done. The first, controlled by
4013 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
4014 list to be aligned to the specific boundary (in bits). This rounding
4015 affects the initial and starting offsets, but not the argument size.
4017 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
4018 optionally rounds the size of the parm to PARM_BOUNDARY. The
4019 initial offset is not affected by this rounding, while the size always
4020 is and the starting offset may be. */
4022 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
4023 initial_offset_ptr is positive because locate_and_pad_parm's
4024 callers pass in the total size of args so far as
4025 initial_offset_ptr. arg_size_ptr is always positive.*/
4028 locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
4029 initial_offset_ptr, offset_ptr, arg_size_ptr)
4030 enum machine_mode passed_mode;
4034 struct args_size *initial_offset_ptr;
4035 struct args_size *offset_ptr;
4036 struct args_size *arg_size_ptr;
4039 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
4040 enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
4041 int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
4042 int boundary_in_bytes = boundary / BITS_PER_UNIT;
4043 int reg_parm_stack_space = 0;
4045 #ifdef REG_PARM_STACK_SPACE
4046 /* If we have found a stack parm before we reach the end of the
4047 area reserved for registers, skip that area. */
4050 #ifdef MAYBE_REG_PARM_STACK_SPACE
4051 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
4053 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
4055 if (reg_parm_stack_space > 0)
4057 if (initial_offset_ptr->var)
4059 initial_offset_ptr->var
4060 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
4061 size_int (reg_parm_stack_space));
4062 initial_offset_ptr->constant = 0;
4064 else if (initial_offset_ptr->constant < reg_parm_stack_space)
4065 initial_offset_ptr->constant = reg_parm_stack_space;
4068 #endif /* REG_PARM_STACK_SPACE */
4070 arg_size_ptr->var = 0;
4071 arg_size_ptr->constant = 0;
4073 #ifdef ARGS_GROW_DOWNWARD
4074 if (initial_offset_ptr->var)
4076 offset_ptr->constant = 0;
4077 offset_ptr->var = size_binop (MINUS_EXPR, integer_zero_node,
4078 initial_offset_ptr->var);
4082 offset_ptr->constant = - initial_offset_ptr->constant;
4083 offset_ptr->var = 0;
4085 if (where_pad != none
4086 && (TREE_CODE (sizetree) != INTEGER_CST
4087 || ((TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)))
4088 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
4089 SUB_PARM_SIZE (*offset_ptr, sizetree);
4090 if (where_pad != downward)
4091 pad_to_arg_alignment (offset_ptr, boundary);
4092 if (initial_offset_ptr->var)
4094 arg_size_ptr->var = size_binop (MINUS_EXPR,
4095 size_binop (MINUS_EXPR,
4097 initial_offset_ptr->var),
4102 arg_size_ptr->constant = (- initial_offset_ptr->constant -
4103 offset_ptr->constant);
4105 #else /* !ARGS_GROW_DOWNWARD */
4106 pad_to_arg_alignment (initial_offset_ptr, boundary);
4107 *offset_ptr = *initial_offset_ptr;
4109 #ifdef PUSH_ROUNDING
4110 if (passed_mode != BLKmode)
4111 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
4114 /* Pad_below needs the pre-rounded size to know how much to pad below
4115 so this must be done before rounding up. */
4116 if (where_pad == downward
4117 /* However, BLKmode args passed in regs have their padding done elsewhere.
4118 The stack slot must be able to hold the entire register. */
4119 && !(in_regs && passed_mode == BLKmode))
4120 pad_below (offset_ptr, passed_mode, sizetree);
4122 if (where_pad != none
4123 && (TREE_CODE (sizetree) != INTEGER_CST
4124 || ((TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)))
4125 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
4127 ADD_PARM_SIZE (*arg_size_ptr, sizetree);
4128 #endif /* ARGS_GROW_DOWNWARD */
4131 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
4132 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
4135 pad_to_arg_alignment (offset_ptr, boundary)
4136 struct args_size *offset_ptr;
4139 int boundary_in_bytes = boundary / BITS_PER_UNIT;
4141 if (boundary > BITS_PER_UNIT)
4143 if (offset_ptr->var)
4146 #ifdef ARGS_GROW_DOWNWARD
4151 (ARGS_SIZE_TREE (*offset_ptr),
4152 boundary / BITS_PER_UNIT);
4153 offset_ptr->constant = 0; /*?*/
4156 offset_ptr->constant =
4157 #ifdef ARGS_GROW_DOWNWARD
4158 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
4160 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
4166 pad_below (offset_ptr, passed_mode, sizetree)
4167 struct args_size *offset_ptr;
4168 enum machine_mode passed_mode;
4171 if (passed_mode != BLKmode)
4173 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
4174 offset_ptr->constant
4175 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
4176 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
4177 - GET_MODE_SIZE (passed_mode));
4181 if (TREE_CODE (sizetree) != INTEGER_CST
4182 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
4184 /* Round the size up to multiple of PARM_BOUNDARY bits. */
4185 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
4187 ADD_PARM_SIZE (*offset_ptr, s2);
4188 SUB_PARM_SIZE (*offset_ptr, sizetree);
4194 round_down (value, divisor)
4198 return size_binop (MULT_EXPR,
4199 size_binop (FLOOR_DIV_EXPR, value, size_int (divisor)),
4200 size_int (divisor));
4203 /* Walk the tree of blocks describing the binding levels within a function
4204 and warn about uninitialized variables.
4205 This is done after calling flow_analysis and before global_alloc
4206 clobbers the pseudo-regs to hard regs. */
4209 uninitialized_vars_warning (block)
4212 register tree decl, sub;
4213 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
4215 if (TREE_CODE (decl) == VAR_DECL
4216 /* These warnings are unreliable for and aggregates
4217 because assigning the fields one by one can fail to convince
4218 flow.c that the entire aggregate was initialized.
4219 Unions are troublesome because members may be shorter. */
4220 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
4221 && DECL_RTL (decl) != 0
4222 && GET_CODE (DECL_RTL (decl)) == REG
4223 && regno_uninitialized (REGNO (DECL_RTL (decl))))
4224 warning_with_decl (decl,
4225 "`%s' might be used uninitialized in this function");
4226 if (TREE_CODE (decl) == VAR_DECL
4227 && DECL_RTL (decl) != 0
4228 && GET_CODE (DECL_RTL (decl)) == REG
4229 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
4230 warning_with_decl (decl,
4231 "variable `%s' might be clobbered by `longjmp' or `vfork'");
4233 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
4234 uninitialized_vars_warning (sub);
4237 /* Do the appropriate part of uninitialized_vars_warning
4238 but for arguments instead of local variables. */
4241 setjmp_args_warning ()
4244 for (decl = DECL_ARGUMENTS (current_function_decl);
4245 decl; decl = TREE_CHAIN (decl))
4246 if (DECL_RTL (decl) != 0
4247 && GET_CODE (DECL_RTL (decl)) == REG
4248 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
4249 warning_with_decl (decl, "argument `%s' might be clobbered by `longjmp' or `vfork'");
4252 /* If this function call setjmp, put all vars into the stack
4253 unless they were declared `register'. */
4256 setjmp_protect (block)
4259 register tree decl, sub;
4260 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
4261 if ((TREE_CODE (decl) == VAR_DECL
4262 || TREE_CODE (decl) == PARM_DECL)
4263 && DECL_RTL (decl) != 0
4264 && GET_CODE (DECL_RTL (decl)) == REG
4265 /* If this variable came from an inline function, it must be
4266 that it's life doesn't overlap the setjmp. If there was a
4267 setjmp in the function, it would already be in memory. We
4268 must exclude such variable because their DECL_RTL might be
4269 set to strange things such as virtual_stack_vars_rtx. */
4270 && ! DECL_FROM_INLINE (decl)
4272 #ifdef NON_SAVING_SETJMP
4273 /* If longjmp doesn't restore the registers,
4274 don't put anything in them. */
4278 ! DECL_REGISTER (decl)))
4279 put_var_into_stack (decl);
4280 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
4281 setjmp_protect (sub);
4284 /* Like the previous function, but for args instead of local variables. */
4287 setjmp_protect_args ()
4289 register tree decl, sub;
4290 for (decl = DECL_ARGUMENTS (current_function_decl);
4291 decl; decl = TREE_CHAIN (decl))
4292 if ((TREE_CODE (decl) == VAR_DECL
4293 || TREE_CODE (decl) == PARM_DECL)
4294 && DECL_RTL (decl) != 0
4295 && GET_CODE (DECL_RTL (decl)) == REG
4297 /* If longjmp doesn't restore the registers,
4298 don't put anything in them. */
4299 #ifdef NON_SAVING_SETJMP
4303 ! DECL_REGISTER (decl)))
4304 put_var_into_stack (decl);
4307 /* Return the context-pointer register corresponding to DECL,
4308 or 0 if it does not need one. */
4311 lookup_static_chain (decl)
4314 tree context = decl_function_context (decl);
4320 /* We treat inline_function_decl as an alias for the current function
4321 because that is the inline function whose vars, types, etc.
4322 are being merged into the current function.
4323 See expand_inline_function. */
4324 if (context == current_function_decl || context == inline_function_decl)
4325 return virtual_stack_vars_rtx;
4327 for (link = context_display; link; link = TREE_CHAIN (link))
4328 if (TREE_PURPOSE (link) == context)
4329 return RTL_EXPR_RTL (TREE_VALUE (link));
4334 /* Convert a stack slot address ADDR for variable VAR
4335 (from a containing function)
4336 into an address valid in this function (using a static chain). */
4339 fix_lexical_addr (addr, var)
4345 tree context = decl_function_context (var);
4346 struct function *fp;
4349 /* If this is the present function, we need not do anything. */
4350 if (context == current_function_decl || context == inline_function_decl)
4353 for (fp = outer_function_chain; fp; fp = fp->next)
4354 if (fp->decl == context)
4360 /* Decode given address as base reg plus displacement. */
4361 if (GET_CODE (addr) == REG)
4362 basereg = addr, displacement = 0;
4363 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
4364 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
4368 /* We accept vars reached via the containing function's
4369 incoming arg pointer and via its stack variables pointer. */
4370 if (basereg == fp->internal_arg_pointer)
4372 /* If reached via arg pointer, get the arg pointer value
4373 out of that function's stack frame.
4375 There are two cases: If a separate ap is needed, allocate a
4376 slot in the outer function for it and dereference it that way.
4377 This is correct even if the real ap is actually a pseudo.
4378 Otherwise, just adjust the offset from the frame pointer to
4381 #ifdef NEED_SEPARATE_AP
4384 if (fp->arg_pointer_save_area == 0)
4385 fp->arg_pointer_save_area
4386 = assign_outer_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0, fp);
4388 addr = fix_lexical_addr (XEXP (fp->arg_pointer_save_area, 0), var);
4389 addr = memory_address (Pmode, addr);
4391 base = copy_to_reg (gen_rtx (MEM, Pmode, addr));
4393 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
4394 base = lookup_static_chain (var);
4398 else if (basereg == virtual_stack_vars_rtx)
4400 /* This is the same code as lookup_static_chain, duplicated here to
4401 avoid an extra call to decl_function_context. */
4404 for (link = context_display; link; link = TREE_CHAIN (link))
4405 if (TREE_PURPOSE (link) == context)
4407 base = RTL_EXPR_RTL (TREE_VALUE (link));
4415 /* Use same offset, relative to appropriate static chain or argument
4417 return plus_constant (base, displacement);
4420 /* Return the address of the trampoline for entering nested fn FUNCTION.
4421 If necessary, allocate a trampoline (in the stack frame)
4422 and emit rtl to initialize its contents (at entry to this function). */
4425 trampoline_address (function)
4431 struct function *fp;
4434 /* Find an existing trampoline and return it. */
4435 for (link = trampoline_list; link; link = TREE_CHAIN (link))
4436 if (TREE_PURPOSE (link) == function)
4438 round_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
4440 for (fp = outer_function_chain; fp; fp = fp->next)
4441 for (link = fp->trampoline_list; link; link = TREE_CHAIN (link))
4442 if (TREE_PURPOSE (link) == function)
4444 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
4446 return round_trampoline_addr (tramp);
4449 /* None exists; we must make one. */
4451 /* Find the `struct function' for the function containing FUNCTION. */
4453 fn_context = decl_function_context (function);
4454 if (fn_context != current_function_decl)
4455 for (fp = outer_function_chain; fp; fp = fp->next)
4456 if (fp->decl == fn_context)
4459 /* Allocate run-time space for this trampoline
4460 (usually in the defining function's stack frame). */
4461 #ifdef ALLOCATE_TRAMPOLINE
4462 tramp = ALLOCATE_TRAMPOLINE (fp);
4464 /* If rounding needed, allocate extra space
4465 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
4466 #ifdef TRAMPOLINE_ALIGNMENT
4467 #define TRAMPOLINE_REAL_SIZE (TRAMPOLINE_SIZE + TRAMPOLINE_ALIGNMENT - 1)
4469 #define TRAMPOLINE_REAL_SIZE (TRAMPOLINE_SIZE)
4472 tramp = assign_outer_stack_local (BLKmode, TRAMPOLINE_REAL_SIZE, 0, fp);
4474 tramp = assign_stack_local (BLKmode, TRAMPOLINE_REAL_SIZE, 0);
4477 /* Record the trampoline for reuse and note it for later initialization
4478 by expand_function_end. */
4481 push_obstacks (fp->function_maybepermanent_obstack,
4482 fp->function_maybepermanent_obstack);
4483 rtlexp = make_node (RTL_EXPR);
4484 RTL_EXPR_RTL (rtlexp) = tramp;
4485 fp->trampoline_list = tree_cons (function, rtlexp, fp->trampoline_list);
4490 /* Make the RTL_EXPR node temporary, not momentary, so that the
4491 trampoline_list doesn't become garbage. */
4492 int momentary = suspend_momentary ();
4493 rtlexp = make_node (RTL_EXPR);
4494 resume_momentary (momentary);
4496 RTL_EXPR_RTL (rtlexp) = tramp;
4497 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
4500 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
4501 return round_trampoline_addr (tramp);
4504 /* Given a trampoline address,
4505 round it to multiple of TRAMPOLINE_ALIGNMENT. */
4508 round_trampoline_addr (tramp)
4511 #ifdef TRAMPOLINE_ALIGNMENT
4512 /* Round address up to desired boundary. */
4513 rtx temp = gen_reg_rtx (Pmode);
4514 temp = expand_binop (Pmode, add_optab, tramp,
4515 GEN_INT (TRAMPOLINE_ALIGNMENT - 1),
4516 temp, 0, OPTAB_LIB_WIDEN);
4517 tramp = expand_binop (Pmode, and_optab, temp,
4518 GEN_INT (- TRAMPOLINE_ALIGNMENT),
4519 temp, 0, OPTAB_LIB_WIDEN);
4524 /* The functions identify_blocks and reorder_blocks provide a way to
4525 reorder the tree of BLOCK nodes, for optimizers that reshuffle or
4526 duplicate portions of the RTL code. Call identify_blocks before
4527 changing the RTL, and call reorder_blocks after. */
4529 /* Put all this function's BLOCK nodes into a vector, and return it.
4530 Also store in each NOTE for the beginning or end of a block
4531 the index of that block in the vector.
4532 The arguments are TOP_BLOCK, the top-level block of the function,
4533 and INSNS, the insn chain of the function. */
4536 identify_blocks (top_block, insns)
4544 int next_block_number = 0;
4545 int current_block_number = 0;
4551 n_blocks = all_blocks (top_block, 0);
4552 block_vector = (tree *) xmalloc (n_blocks * sizeof (tree));
4553 block_stack = (int *) alloca (n_blocks * sizeof (int));
4555 all_blocks (top_block, block_vector);
4557 for (insn = insns; insn; insn = NEXT_INSN (insn))
4558 if (GET_CODE (insn) == NOTE)
4560 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
4562 block_stack[depth++] = current_block_number;
4563 current_block_number = next_block_number;
4564 NOTE_BLOCK_NUMBER (insn) = next_block_number++;
4566 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
4568 current_block_number = block_stack[--depth];
4569 NOTE_BLOCK_NUMBER (insn) = current_block_number;
4573 return block_vector;
4576 /* Given BLOCK_VECTOR which was returned by identify_blocks,
4577 and a revised instruction chain, rebuild the tree structure
4578 of BLOCK nodes to correspond to the new order of RTL.
4579 The new block tree is inserted below TOP_BLOCK.
4580 Returns the current top-level block. */
4583 reorder_blocks (block_vector, top_block, insns)
4588 tree current_block = top_block;
4591 if (block_vector == 0)
4594 /* Prune the old tree away, so that it doesn't get in the way. */
4595 BLOCK_SUBBLOCKS (current_block) = 0;
4597 for (insn = insns; insn; insn = NEXT_INSN (insn))
4598 if (GET_CODE (insn) == NOTE)
4600 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
4602 tree block = block_vector[NOTE_BLOCK_NUMBER (insn)];
4603 /* If we have seen this block before, copy it. */
4604 if (TREE_ASM_WRITTEN (block))
4605 block = copy_node (block);
4606 BLOCK_SUBBLOCKS (block) = 0;
4607 TREE_ASM_WRITTEN (block) = 1;
4608 BLOCK_SUPERCONTEXT (block) = current_block;
4609 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
4610 BLOCK_SUBBLOCKS (current_block) = block;
4611 current_block = block;
4612 NOTE_SOURCE_FILE (insn) = 0;
4614 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
4616 BLOCK_SUBBLOCKS (current_block)
4617 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
4618 current_block = BLOCK_SUPERCONTEXT (current_block);
4619 NOTE_SOURCE_FILE (insn) = 0;
4623 return current_block;
4626 /* Reverse the order of elements in the chain T of blocks,
4627 and return the new head of the chain (old last element). */
4633 register tree prev = 0, decl, next;
4634 for (decl = t; decl; decl = next)
4636 next = BLOCK_CHAIN (decl);
4637 BLOCK_CHAIN (decl) = prev;
4643 /* Count the subblocks of BLOCK, and list them all into the vector VECTOR.
4644 Also clear TREE_ASM_WRITTEN in all blocks. */
4647 all_blocks (block, vector)
4654 TREE_ASM_WRITTEN (block) = 0;
4655 /* Record this block. */
4659 /* Record the subblocks, and their subblocks. */
4660 for (subblocks = BLOCK_SUBBLOCKS (block);
4661 subblocks; subblocks = BLOCK_CHAIN (subblocks))
4662 n_blocks += all_blocks (subblocks, vector ? vector + n_blocks : 0);
4667 /* Build bytecode call descriptor for function SUBR. */
4670 bc_build_calldesc (subr)
4673 tree calldesc = 0, arg;
4676 /* Build the argument description vector in reverse order. */
4677 DECL_ARGUMENTS (subr) = nreverse (DECL_ARGUMENTS (subr));
4680 for (arg = DECL_ARGUMENTS (subr); arg; arg = TREE_CHAIN (arg))
4684 calldesc = tree_cons ((tree) 0, size_in_bytes (TREE_TYPE (arg)), calldesc);
4685 calldesc = tree_cons ((tree) 0, bc_runtime_type_code (TREE_TYPE (arg)), calldesc);
4688 DECL_ARGUMENTS (subr) = nreverse (DECL_ARGUMENTS (subr));
4690 /* Prepend the function's return type. */
4691 calldesc = tree_cons ((tree) 0,
4692 size_in_bytes (TREE_TYPE (TREE_TYPE (subr))),
4695 calldesc = tree_cons ((tree) 0,
4696 bc_runtime_type_code (TREE_TYPE (TREE_TYPE (subr))),
4699 /* Prepend the arg count. */
4700 calldesc = tree_cons ((tree) 0, build_int_2 (nargs, 0), calldesc);
4702 /* Output the call description vector and get its address. */
4703 calldesc = build_nt (CONSTRUCTOR, (tree) 0, calldesc);
4704 TREE_TYPE (calldesc) = build_array_type (integer_type_node,
4705 build_index_type (build_int_2 (nargs * 2, 0)));
4707 return output_constant_def (calldesc);
4711 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
4712 and initialize static variables for generating RTL for the statements
4716 init_function_start (subr, filename, line)
4723 if (output_bytecode)
4725 this_function_decl = subr;
4726 this_function_calldesc = bc_build_calldesc (subr);
4727 local_vars_size = 0;
4729 max_stack_depth = 0;
4730 stmt_expr_depth = 0;
4734 init_stmt_for_function ();
4736 cse_not_expected = ! optimize;
4738 /* Caller save not needed yet. */
4739 caller_save_needed = 0;
4741 /* No stack slots have been made yet. */
4742 stack_slot_list = 0;
4744 /* There is no stack slot for handling nonlocal gotos. */
4745 nonlocal_goto_handler_slot = 0;
4746 nonlocal_goto_stack_level = 0;
4748 /* No labels have been declared for nonlocal use. */
4749 nonlocal_labels = 0;
4751 /* No function calls so far in this function. */
4752 function_call_count = 0;
4754 /* No parm regs have been allocated.
4755 (This is important for output_inline_function.) */
4756 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4758 /* Initialize the RTL mechanism. */
4761 /* Initialize the queue of pending postincrement and postdecrements,
4762 and some other info in expr.c. */
4765 /* We haven't done register allocation yet. */
4768 init_const_rtx_hash_table ();
4770 current_function_name = (*decl_printable_name) (subr, &junk);
4772 /* Nonzero if this is a nested function that uses a static chain. */
4774 current_function_needs_context
4775 = (decl_function_context (current_function_decl) != 0);
4777 /* Set if a call to setjmp is seen. */
4778 current_function_calls_setjmp = 0;
4780 /* Set if a call to longjmp is seen. */
4781 current_function_calls_longjmp = 0;
4783 current_function_calls_alloca = 0;
4784 current_function_has_nonlocal_label = 0;
4785 current_function_has_nonlocal_goto = 0;
4786 current_function_contains_functions = 0;
4788 current_function_returns_pcc_struct = 0;
4789 current_function_returns_struct = 0;
4790 current_function_epilogue_delay_list = 0;
4791 current_function_uses_const_pool = 0;
4792 current_function_uses_pic_offset_table = 0;
4794 /* We have not yet needed to make a label to jump to for tail-recursion. */
4795 tail_recursion_label = 0;
4797 /* We haven't had a need to make a save area for ap yet. */
4799 arg_pointer_save_area = 0;
4801 /* No stack slots allocated yet. */
4804 /* No SAVE_EXPRs in this function yet. */
4807 /* No RTL_EXPRs in this function yet. */
4810 /* We have not allocated any temporaries yet. */
4812 temp_slot_level = 0;
4813 target_temp_slot_level = 0;
4815 /* Within function body, compute a type's size as soon it is laid out. */
4816 immediate_size_expand++;
4818 /* We haven't made any trampolines for this function yet. */
4819 trampoline_list = 0;
4821 init_pending_stack_adjust ();
4822 inhibit_defer_pop = 0;
4824 current_function_outgoing_args_size = 0;
4826 /* Prevent ever trying to delete the first instruction of a function.
4827 Also tell final how to output a linenum before the function prologue. */
4828 emit_line_note (filename, line);
4830 /* Make sure first insn is a note even if we don't want linenums.
4831 This makes sure the first insn will never be deleted.
4832 Also, final expects a note to appear there. */
4833 emit_note (NULL_PTR, NOTE_INSN_DELETED);
4835 /* Set flags used by final.c. */
4836 if (aggregate_value_p (DECL_RESULT (subr)))
4838 #ifdef PCC_STATIC_STRUCT_RETURN
4839 current_function_returns_pcc_struct = 1;
4841 current_function_returns_struct = 1;
4844 /* Warn if this value is an aggregate type,
4845 regardless of which calling convention we are using for it. */
4846 if (warn_aggregate_return
4847 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
4848 warning ("function returns an aggregate");
4850 current_function_returns_pointer
4851 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
4853 /* Indicate that we need to distinguish between the return value of the
4854 present function and the return value of a function being called. */
4855 rtx_equal_function_value_matters = 1;
4857 /* Indicate that we have not instantiated virtual registers yet. */
4858 virtuals_instantiated = 0;
4860 /* Indicate we have no need of a frame pointer yet. */
4861 frame_pointer_needed = 0;
4863 /* By default assume not varargs or stdarg. */
4864 current_function_varargs = 0;
4865 current_function_stdarg = 0;
4868 /* Indicate that the current function uses extra args
4869 not explicitly mentioned in the argument list in any fashion. */
4874 current_function_varargs = 1;
4877 /* Expand a call to __main at the beginning of a possible main function. */
4879 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
4880 #undef HAS_INIT_SECTION
4881 #define HAS_INIT_SECTION
4885 expand_main_function ()
4887 if (!output_bytecode)
4889 /* The zero below avoids a possible parse error */
4891 #if !defined (HAS_INIT_SECTION)
4892 emit_library_call (gen_rtx (SYMBOL_REF, Pmode, NAME__MAIN), 0,
4894 #endif /* not HAS_INIT_SECTION */
4898 extern struct obstack permanent_obstack;
4900 /* Expand start of bytecode function. See comment at
4901 expand_function_start below for details. */
4904 bc_expand_function_start (subr, parms_have_cleanups)
4906 int parms_have_cleanups;
4908 char label[20], *name;
4913 if (TREE_PUBLIC (subr))
4914 bc_globalize_label (IDENTIFIER_POINTER (DECL_NAME (subr)));
4916 #ifdef DEBUG_PRINT_CODE
4917 fprintf (stderr, "\n<func %s>\n", IDENTIFIER_POINTER (DECL_NAME (subr)));
4920 for (argsz = 0, thisarg = DECL_ARGUMENTS (subr); thisarg; thisarg = TREE_CHAIN (thisarg))
4922 if (DECL_RTL (thisarg))
4923 abort (); /* Should be NULL here I think. */
4924 else if (TREE_CONSTANT (DECL_SIZE (thisarg)))
4926 DECL_RTL (thisarg) = bc_gen_rtx ((char *) 0, argsz, (struct bc_label *) 0);
4927 argsz += TREE_INT_CST_LOW (DECL_SIZE (thisarg));
4931 /* Variable-sized objects are pointers to their storage. */
4932 DECL_RTL (thisarg) = bc_gen_rtx ((char *) 0, argsz, (struct bc_label *) 0);
4933 argsz += POINTER_SIZE;
4937 bc_begin_function (bc_xstrdup (IDENTIFIER_POINTER (DECL_NAME (subr))));
4939 ASM_GENERATE_INTERNAL_LABEL (label, "LX", nlab);
4942 name = (char *) obstack_copy0 (&permanent_obstack, label, strlen (label));
4943 this_function_callinfo = bc_gen_rtx (name, 0, (struct bc_label *) 0);
4944 this_function_bytecode =
4945 bc_emit_trampoline (BYTECODE_LABEL (this_function_callinfo));
4949 /* Expand end of bytecode function. See details the comment of
4950 expand_function_end(), below. */
4953 bc_expand_function_end ()
4957 expand_null_return ();
4959 /* Emit any fixup code. This must be done before the call to
4960 to BC_END_FUNCTION (), since that will cause the bytecode
4961 segment to be finished off and closed. */
4963 expand_fixups (NULL_RTX);
4965 ptrconsts = bc_end_function ();
4967 bc_align_const (2 /* INT_ALIGN */);
4969 /* If this changes also make sure to change bc-interp.h! */
4971 bc_emit_const_labeldef (BYTECODE_LABEL (this_function_callinfo));
4972 bc_emit_const ((char *) &max_stack_depth, sizeof max_stack_depth);
4973 bc_emit_const ((char *) &local_vars_size, sizeof local_vars_size);
4974 bc_emit_const_labelref (this_function_bytecode, 0);
4975 bc_emit_const_labelref (ptrconsts, 0);
4976 bc_emit_const_labelref (BYTECODE_LABEL (this_function_calldesc), 0);
4980 /* Start the RTL for a new function, and set variables used for
4982 SUBR is the FUNCTION_DECL node.
4983 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4984 the function's parameters, which must be run at any return statement. */
4987 expand_function_start (subr, parms_have_cleanups)
4989 int parms_have_cleanups;
4995 if (output_bytecode)
4997 bc_expand_function_start (subr, parms_have_cleanups);
5001 /* Make sure volatile mem refs aren't considered
5002 valid operands of arithmetic insns. */
5003 init_recog_no_volatile ();
5005 /* If function gets a static chain arg, store it in the stack frame.
5006 Do this first, so it gets the first stack slot offset. */
5007 if (current_function_needs_context)
5009 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
5011 #ifdef SMALL_REGISTER_CLASSES
5012 /* Delay copying static chain if it is not a register to avoid
5013 conflicts with regs used for parameters. */
5014 if (GET_CODE (static_chain_incoming_rtx) == REG)
5016 emit_move_insn (last_ptr, static_chain_incoming_rtx);
5019 /* If the parameters of this function need cleaning up, get a label
5020 for the beginning of the code which executes those cleanups. This must
5021 be done before doing anything with return_label. */
5022 if (parms_have_cleanups)
5023 cleanup_label = gen_label_rtx ();
5027 /* Make the label for return statements to jump to, if this machine
5028 does not have a one-instruction return and uses an epilogue,
5029 or if it returns a structure, or if it has parm cleanups. */
5031 if (cleanup_label == 0 && HAVE_return
5032 && ! current_function_returns_pcc_struct
5033 && ! (current_function_returns_struct && ! optimize))
5036 return_label = gen_label_rtx ();
5038 return_label = gen_label_rtx ();
5041 /* Initialize rtx used to return the value. */
5042 /* Do this before assign_parms so that we copy the struct value address
5043 before any library calls that assign parms might generate. */
5045 /* Decide whether to return the value in memory or in a register. */
5046 if (aggregate_value_p (DECL_RESULT (subr)))
5048 /* Returning something that won't go in a register. */
5049 register rtx value_address = 0;
5051 #ifdef PCC_STATIC_STRUCT_RETURN
5052 if (current_function_returns_pcc_struct)
5054 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
5055 value_address = assemble_static_space (size);
5060 /* Expect to be passed the address of a place to store the value.
5061 If it is passed as an argument, assign_parms will take care of
5063 if (struct_value_incoming_rtx)
5065 value_address = gen_reg_rtx (Pmode);
5066 emit_move_insn (value_address, struct_value_incoming_rtx);
5071 DECL_RTL (DECL_RESULT (subr))
5072 = gen_rtx (MEM, DECL_MODE (DECL_RESULT (subr)), value_address);
5073 MEM_IN_STRUCT_P (DECL_RTL (DECL_RESULT (subr)))
5074 = AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
5077 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
5078 /* If return mode is void, this decl rtl should not be used. */
5079 DECL_RTL (DECL_RESULT (subr)) = 0;
5080 else if (parms_have_cleanups)
5082 /* If function will end with cleanup code for parms,
5083 compute the return values into a pseudo reg,
5084 which we will copy into the true return register
5085 after the cleanups are done. */
5087 enum machine_mode mode = DECL_MODE (DECL_RESULT (subr));
5089 #ifdef PROMOTE_FUNCTION_RETURN
5090 tree type = TREE_TYPE (DECL_RESULT (subr));
5091 int unsignedp = TREE_UNSIGNED (type);
5093 mode = promote_mode (type, mode, &unsignedp, 1);
5096 DECL_RTL (DECL_RESULT (subr)) = gen_reg_rtx (mode);
5099 /* Scalar, returned in a register. */
5101 #ifdef FUNCTION_OUTGOING_VALUE
5102 DECL_RTL (DECL_RESULT (subr))
5103 = FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (subr)), subr);
5105 DECL_RTL (DECL_RESULT (subr))
5106 = FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (subr)), subr);
5109 /* Mark this reg as the function's return value. */
5110 if (GET_CODE (DECL_RTL (DECL_RESULT (subr))) == REG)
5112 REG_FUNCTION_VALUE_P (DECL_RTL (DECL_RESULT (subr))) = 1;
5113 /* Needed because we may need to move this to memory
5114 in case it's a named return value whose address is taken. */
5115 DECL_REGISTER (DECL_RESULT (subr)) = 1;
5119 /* Initialize rtx for parameters and local variables.
5120 In some cases this requires emitting insns. */
5122 assign_parms (subr, 0);
5124 #ifdef SMALL_REGISTER_CLASSES
5125 /* Copy the static chain now if it wasn't a register. The delay is to
5126 avoid conflicts with the parameter passing registers. */
5128 if (current_function_needs_context)
5129 if (GET_CODE (static_chain_incoming_rtx) != REG)
5130 emit_move_insn (last_ptr, static_chain_incoming_rtx);
5133 /* The following was moved from init_function_start.
5134 The move is supposed to make sdb output more accurate. */
5135 /* Indicate the beginning of the function body,
5136 as opposed to parm setup. */
5137 emit_note (NULL_PTR, NOTE_INSN_FUNCTION_BEG);
5139 /* If doing stupid allocation, mark parms as born here. */
5141 if (GET_CODE (get_last_insn ()) != NOTE)
5142 emit_note (NULL_PTR, NOTE_INSN_DELETED);
5143 parm_birth_insn = get_last_insn ();
5147 for (i = LAST_VIRTUAL_REGISTER + 1; i < max_parm_reg; i++)
5148 use_variable (regno_reg_rtx[i]);
5150 if (current_function_internal_arg_pointer != virtual_incoming_args_rtx)
5151 use_variable (current_function_internal_arg_pointer);
5154 /* Fetch static chain values for containing functions. */
5155 tem = decl_function_context (current_function_decl);
5156 /* If not doing stupid register allocation copy the static chain
5157 pointer into a pseudo. If we have small register classes, copy the
5158 value from memory if static_chain_incoming_rtx is a REG. If we do
5159 stupid register allocation, we use the stack address generated above. */
5160 if (tem && ! obey_regdecls)
5162 #ifdef SMALL_REGISTER_CLASSES
5163 /* If the static chain originally came in a register, put it back
5164 there, then move it out in the next insn. The reason for
5165 this peculiar code is to satisfy function integration. */
5166 if (GET_CODE (static_chain_incoming_rtx) == REG)
5167 emit_move_insn (static_chain_incoming_rtx, last_ptr);
5170 last_ptr = copy_to_reg (static_chain_incoming_rtx);
5173 context_display = 0;
5176 tree rtlexp = make_node (RTL_EXPR);
5178 RTL_EXPR_RTL (rtlexp) = last_ptr;
5179 context_display = tree_cons (tem, rtlexp, context_display);
5180 tem = decl_function_context (tem);
5183 /* Chain thru stack frames, assuming pointer to next lexical frame
5184 is found at the place we always store it. */
5185 #ifdef FRAME_GROWS_DOWNWARD
5186 last_ptr = plus_constant (last_ptr, - GET_MODE_SIZE (Pmode));
5188 last_ptr = copy_to_reg (gen_rtx (MEM, Pmode,
5189 memory_address (Pmode, last_ptr)));
5191 /* If we are not optimizing, ensure that we know that this
5192 piece of context is live over the entire function. */
5194 save_expr_regs = gen_rtx (EXPR_LIST, VOIDmode, last_ptr,
5198 /* After the display initializations is where the tail-recursion label
5199 should go, if we end up needing one. Ensure we have a NOTE here
5200 since some things (like trampolines) get placed before this. */
5201 tail_recursion_reentry = emit_note (NULL_PTR, NOTE_INSN_DELETED);
5203 /* Evaluate now the sizes of any types declared among the arguments. */
5204 for (tem = nreverse (get_pending_sizes ()); tem; tem = TREE_CHAIN (tem))
5205 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode, 0);
5207 /* Make sure there is a line number after the function entry setup code. */
5208 force_next_line_note ();
5211 /* Generate RTL for the end of the current function.
5212 FILENAME and LINE are the current position in the source file.
5214 It is up to language-specific callers to do cleanups for parameters--
5215 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
5218 expand_function_end (filename, line, end_bindings)
5226 static rtx initial_trampoline;
5228 if (output_bytecode)
5230 bc_expand_function_end ();
5234 #ifdef NON_SAVING_SETJMP
5235 /* Don't put any variables in registers if we call setjmp
5236 on a machine that fails to restore the registers. */
5237 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
5239 if (DECL_INITIAL (current_function_decl) != error_mark_node)
5240 setjmp_protect (DECL_INITIAL (current_function_decl));
5242 setjmp_protect_args ();
5246 /* Save the argument pointer if a save area was made for it. */
5247 if (arg_pointer_save_area)
5249 rtx x = gen_move_insn (arg_pointer_save_area, virtual_incoming_args_rtx);
5250 emit_insn_before (x, tail_recursion_reentry);
5253 /* Initialize any trampolines required by this function. */
5254 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5256 tree function = TREE_PURPOSE (link);
5257 rtx context = lookup_static_chain (function);
5258 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
5261 /* First make sure this compilation has a template for
5262 initializing trampolines. */
5263 if (initial_trampoline == 0)
5265 end_temporary_allocation ();
5267 = gen_rtx (MEM, BLKmode, assemble_trampoline_template ());
5268 resume_temporary_allocation ();
5271 /* Generate insns to initialize the trampoline. */
5273 tramp = change_address (initial_trampoline, BLKmode,
5274 round_trampoline_addr (XEXP (tramp, 0)));
5275 emit_block_move (tramp, initial_trampoline, GEN_INT (TRAMPOLINE_SIZE),
5276 FUNCTION_BOUNDARY / BITS_PER_UNIT);
5277 INITIALIZE_TRAMPOLINE (XEXP (tramp, 0),
5278 XEXP (DECL_RTL (function), 0), context);
5282 /* Put those insns at entry to the containing function (this one). */
5283 emit_insns_before (seq, tail_recursion_reentry);
5286 /* Warn about unused parms if extra warnings were specified. */
5287 if (warn_unused && extra_warnings)
5291 for (decl = DECL_ARGUMENTS (current_function_decl);
5292 decl; decl = TREE_CHAIN (decl))
5293 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
5294 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
5295 warning_with_decl (decl, "unused parameter `%s'");
5298 /* Delete handlers for nonlocal gotos if nothing uses them. */
5299 if (nonlocal_goto_handler_slot != 0 && !current_function_has_nonlocal_label)
5302 /* End any sequences that failed to be closed due to syntax errors. */
5303 while (in_sequence_p ())
5306 /* Outside function body, can't compute type's actual size
5307 until next function's body starts. */
5308 immediate_size_expand--;
5310 /* If doing stupid register allocation,
5311 mark register parms as dying here. */
5316 for (i = LAST_VIRTUAL_REGISTER + 1; i < max_parm_reg; i++)
5317 use_variable (regno_reg_rtx[i]);
5319 /* Likewise for the regs of all the SAVE_EXPRs in the function. */
5321 for (tem = save_expr_regs; tem; tem = XEXP (tem, 1))
5323 use_variable (XEXP (tem, 0));
5324 use_variable_after (XEXP (tem, 0), parm_birth_insn);
5327 if (current_function_internal_arg_pointer != virtual_incoming_args_rtx)
5328 use_variable (current_function_internal_arg_pointer);
5331 clear_pending_stack_adjust ();
5332 do_pending_stack_adjust ();
5334 /* Mark the end of the function body.
5335 If control reaches this insn, the function can drop through
5336 without returning a value. */
5337 emit_note (NULL_PTR, NOTE_INSN_FUNCTION_END);
5339 /* Output a linenumber for the end of the function.
5340 SDB depends on this. */
5341 emit_line_note_force (filename, line);
5343 /* Output the label for the actual return from the function,
5344 if one is expected. This happens either because a function epilogue
5345 is used instead of a return instruction, or because a return was done
5346 with a goto in order to run local cleanups, or because of pcc-style
5347 structure returning. */
5350 emit_label (return_label);
5352 /* C++ uses this. */
5354 expand_end_bindings (0, 0, 0);
5356 /* If we had calls to alloca, and this machine needs
5357 an accurate stack pointer to exit the function,
5358 insert some code to save and restore the stack pointer. */
5359 #ifdef EXIT_IGNORE_STACK
5360 if (! EXIT_IGNORE_STACK)
5362 if (current_function_calls_alloca)
5366 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
5367 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
5370 /* If scalar return value was computed in a pseudo-reg,
5371 copy that to the hard return register. */
5372 if (DECL_RTL (DECL_RESULT (current_function_decl)) != 0
5373 && GET_CODE (DECL_RTL (DECL_RESULT (current_function_decl))) == REG
5374 && (REGNO (DECL_RTL (DECL_RESULT (current_function_decl)))
5375 >= FIRST_PSEUDO_REGISTER))
5377 rtx real_decl_result;
5379 #ifdef FUNCTION_OUTGOING_VALUE
5381 = FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl)),
5382 current_function_decl);
5385 = FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl)),
5386 current_function_decl);
5388 REG_FUNCTION_VALUE_P (real_decl_result) = 1;
5389 emit_move_insn (real_decl_result,
5390 DECL_RTL (DECL_RESULT (current_function_decl)));
5391 emit_insn (gen_rtx (USE, VOIDmode, real_decl_result));
5394 /* If returning a structure, arrange to return the address of the value
5395 in a place where debuggers expect to find it.
5397 If returning a structure PCC style,
5398 the caller also depends on this value.
5399 And current_function_returns_pcc_struct is not necessarily set. */
5400 if (current_function_returns_struct
5401 || current_function_returns_pcc_struct)
5403 rtx value_address = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
5404 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
5405 #ifdef FUNCTION_OUTGOING_VALUE
5407 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
5408 current_function_decl);
5411 = FUNCTION_VALUE (build_pointer_type (type),
5412 current_function_decl);
5415 /* Mark this as a function return value so integrate will delete the
5416 assignment and USE below when inlining this function. */
5417 REG_FUNCTION_VALUE_P (outgoing) = 1;
5419 emit_move_insn (outgoing, value_address);
5420 use_variable (outgoing);
5423 /* Output a return insn if we are using one.
5424 Otherwise, let the rtl chain end here, to drop through
5425 into the epilogue. */
5430 emit_jump_insn (gen_return ());
5435 /* Fix up any gotos that jumped out to the outermost
5436 binding level of the function.
5437 Must follow emitting RETURN_LABEL. */
5439 /* If you have any cleanups to do at this point,
5440 and they need to create temporary variables,
5441 then you will lose. */
5442 expand_fixups (get_insns ());
5445 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
5447 static int *prologue;
5448 static int *epilogue;
5450 /* Create an array that records the INSN_UIDs of INSNS (either a sequence
5451 or a single insn). */
5454 record_insns (insns)
5459 if (GET_CODE (insns) == SEQUENCE)
5461 int len = XVECLEN (insns, 0);
5462 vec = (int *) oballoc ((len + 1) * sizeof (int));
5465 vec[len] = INSN_UID (XVECEXP (insns, 0, len));
5469 vec = (int *) oballoc (2 * sizeof (int));
5470 vec[0] = INSN_UID (insns);
5476 /* Determine how many INSN_UIDs in VEC are part of INSN. */
5479 contains (insn, vec)
5485 if (GET_CODE (insn) == INSN
5486 && GET_CODE (PATTERN (insn)) == SEQUENCE)
5489 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
5490 for (j = 0; vec[j]; j++)
5491 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == vec[j])
5497 for (j = 0; vec[j]; j++)
5498 if (INSN_UID (insn) == vec[j])
5504 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
5505 this into place with notes indicating where the prologue ends and where
5506 the epilogue begins. Update the basic block information when possible. */
5509 thread_prologue_and_epilogue_insns (f)
5512 #ifdef HAVE_prologue
5515 rtx head, seq, insn;
5517 /* The first insn (a NOTE_INSN_DELETED) is followed by zero or more
5518 prologue insns and a NOTE_INSN_PROLOGUE_END. */
5519 emit_note_after (NOTE_INSN_PROLOGUE_END, f);
5520 seq = gen_prologue ();
5521 head = emit_insn_after (seq, f);
5523 /* Include the new prologue insns in the first block. Ignore them
5524 if they form a basic block unto themselves. */
5525 if (basic_block_head && n_basic_blocks
5526 && GET_CODE (basic_block_head[0]) != CODE_LABEL)
5527 basic_block_head[0] = NEXT_INSN (f);
5529 /* Retain a map of the prologue insns. */
5530 prologue = record_insns (GET_CODE (seq) == SEQUENCE ? seq : head);
5536 #ifdef HAVE_epilogue
5539 rtx insn = get_last_insn ();
5540 rtx prev = prev_nonnote_insn (insn);
5542 /* If we end with a BARRIER, we don't need an epilogue. */
5543 if (! (prev && GET_CODE (prev) == BARRIER))
5549 /* The last basic block ends with a NOTE_INSN_EPILOGUE_BEG, the
5550 epilogue insns, the USE insns at the end of a function,
5551 the jump insn that returns, and then a BARRIER. */
5553 /* Move the USE insns at the end of a function onto a list. */
5555 && GET_CODE (prev) == INSN
5556 && GET_CODE (PATTERN (prev)) == USE)
5559 prev = prev_nonnote_insn (prev);
5561 NEXT_INSN (PREV_INSN (tem)) = NEXT_INSN (tem);
5562 PREV_INSN (NEXT_INSN (tem)) = PREV_INSN (tem);
5565 NEXT_INSN (tem) = first_use;
5566 PREV_INSN (first_use) = tem;
5573 emit_barrier_after (insn);
5575 seq = gen_epilogue ();
5576 tail = emit_jump_insn_after (seq, insn);
5578 /* Insert the USE insns immediately before the return insn, which
5579 must be the first instruction before the final barrier. */
5582 tem = prev_nonnote_insn (get_last_insn ());
5583 NEXT_INSN (PREV_INSN (tem)) = first_use;
5584 PREV_INSN (first_use) = PREV_INSN (tem);
5585 PREV_INSN (tem) = last_use;
5586 NEXT_INSN (last_use) = tem;
5589 emit_note_after (NOTE_INSN_EPILOGUE_BEG, insn);
5591 /* Include the new epilogue insns in the last block. Ignore
5592 them if they form a basic block unto themselves. */
5593 if (basic_block_end && n_basic_blocks
5594 && GET_CODE (basic_block_end[n_basic_blocks - 1]) != JUMP_INSN)
5595 basic_block_end[n_basic_blocks - 1] = tail;
5597 /* Retain a map of the epilogue insns. */
5598 epilogue = record_insns (GET_CODE (seq) == SEQUENCE ? seq : tail);
5606 /* Reposition the prologue-end and epilogue-begin notes after instruction
5607 scheduling and delayed branch scheduling. */
5610 reposition_prologue_and_epilogue_notes (f)
5613 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
5614 /* Reposition the prologue and epilogue notes. */
5622 register rtx insn, note = 0;
5624 /* Scan from the beginning until we reach the last prologue insn.
5625 We apparently can't depend on basic_block_{head,end} after
5627 for (len = 0; prologue[len]; len++)
5629 for (insn = f; len && insn; insn = NEXT_INSN (insn))
5631 if (GET_CODE (insn) == NOTE)
5633 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
5636 else if ((len -= contains (insn, prologue)) == 0)
5638 /* Find the prologue-end note if we haven't already, and
5639 move it to just after the last prologue insn. */
5642 for (note = insn; note = NEXT_INSN (note);)
5643 if (GET_CODE (note) == NOTE
5644 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
5647 next = NEXT_INSN (note);
5648 prev = PREV_INSN (note);
5650 NEXT_INSN (prev) = next;
5652 PREV_INSN (next) = prev;
5653 add_insn_after (note, insn);
5660 register rtx insn, note = 0;
5662 /* Scan from the end until we reach the first epilogue insn.
5663 We apparently can't depend on basic_block_{head,end} after
5665 for (len = 0; epilogue[len]; len++)
5667 for (insn = get_last_insn (); len && insn; insn = PREV_INSN (insn))
5669 if (GET_CODE (insn) == NOTE)
5671 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
5674 else if ((len -= contains (insn, epilogue)) == 0)
5676 /* Find the epilogue-begin note if we haven't already, and
5677 move it to just before the first epilogue insn. */
5680 for (note = insn; note = PREV_INSN (note);)
5681 if (GET_CODE (note) == NOTE
5682 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
5685 next = NEXT_INSN (note);
5686 prev = PREV_INSN (note);
5688 NEXT_INSN (prev) = next;
5690 PREV_INSN (next) = prev;
5691 add_insn_after (note, PREV_INSN (insn));
5696 #endif /* HAVE_prologue or HAVE_epilogue */