1 /* Expands front end tree to back end RTL for GNU C-Compiler
2 Copyright (C) 1987, 88, 89, 91, 92, 1993 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, 675 Mass Ave, Cambridge, MA 02139, USA. */
21 /* This file handles the generation of rtl code from tree structure
22 at the level of the function as a whole.
23 It creates the rtl expressions for parameters and auto variables
24 and has full responsibility for allocating stack slots.
26 `expand_function_start' is called at the beginning of a function,
27 before the function body is parsed, and `expand_function_end' is
28 called after parsing the body.
30 Call `assign_stack_local' to allocate a stack slot for a local variable.
31 This is usually done during the RTL generation for the function body,
32 but it can also be done in the reload pass when a pseudo-register does
33 not get a hard register.
35 Call `put_var_into_stack' when you learn, belatedly, that a variable
36 previously given a pseudo-register must in fact go in the stack.
37 This function changes the DECL_RTL to be a stack slot instead of a reg
38 then scans all the RTL instructions so far generated to correct them. */
48 #include "insn-flags.h"
50 #include "insn-codes.h"
52 #include "hard-reg-set.h"
53 #include "insn-config.h"
56 #include "basic-block.h"
60 /* Some systems use __main in a way incompatible with its use in gcc, in these
61 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
62 give the same symbol without quotes for an alternative entry point. You
63 must define both, or niether. */
65 #define NAME__MAIN "__main"
66 #define SYMBOL__MAIN __main
69 /* Round a value to the lowest integer less than it that is a multiple of
70 the required alignment. Avoid using division in case the value is
71 negative. Assume the alignment is a power of two. */
72 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
74 /* Similar, but round to the next highest integer that meets the
76 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
78 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
79 during rtl generation. If they are different register numbers, this is
80 always true. It may also be true if
81 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
82 generation. See fix_lexical_addr for details. */
84 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
85 #define NEED_SEPARATE_AP
88 /* Number of bytes of args popped by function being compiled on its return.
89 Zero if no bytes are to be popped.
90 May affect compilation of return insn or of function epilogue. */
92 int current_function_pops_args;
94 /* Nonzero if function being compiled needs to be given an address
95 where the value should be stored. */
97 int current_function_returns_struct;
99 /* Nonzero if function being compiled needs to
100 return the address of where it has put a structure value. */
102 int current_function_returns_pcc_struct;
104 /* Nonzero if function being compiled needs to be passed a static chain. */
106 int current_function_needs_context;
108 /* Nonzero if function being compiled can call setjmp. */
110 int current_function_calls_setjmp;
112 /* Nonzero if function being compiled can call longjmp. */
114 int current_function_calls_longjmp;
116 /* Nonzero if function being compiled receives nonlocal gotos
117 from nested functions. */
119 int current_function_has_nonlocal_label;
121 /* Nonzero if function being compiled has nonlocal gotos to parent
124 int current_function_has_nonlocal_goto;
126 /* Nonzero if function being compiled contains nested functions. */
128 int current_function_contains_functions;
130 /* Nonzero if function being compiled can call alloca,
131 either as a subroutine or builtin. */
133 int current_function_calls_alloca;
135 /* Nonzero if the current function returns a pointer type */
137 int current_function_returns_pointer;
139 /* If some insns can be deferred to the delay slots of the epilogue, the
140 delay list for them is recorded here. */
142 rtx current_function_epilogue_delay_list;
144 /* If function's args have a fixed size, this is that size, in bytes.
146 May affect compilation of return insn or of function epilogue. */
148 int current_function_args_size;
150 /* # bytes the prologue should push and pretend that the caller pushed them.
151 The prologue must do this, but only if parms can be passed in registers. */
153 int current_function_pretend_args_size;
155 /* # of bytes of outgoing arguments required to be pushed by the prologue.
156 If this is non-zero, it means that ACCUMULATE_OUTGOING_ARGS was defined
157 and no stack adjusts will be done on function calls. */
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 /* Quantities of various kinds of registers
172 used for the current function's args. */
174 CUMULATIVE_ARGS current_function_args_info;
176 /* Name of function now being compiled. */
178 char *current_function_name;
180 /* If non-zero, an RTL expression for that location at which the current
181 function returns its result. Always equal to
182 DECL_RTL (DECL_RESULT (current_function_decl)), but provided
183 independently of the tree structures. */
185 rtx current_function_return_rtx;
187 /* Nonzero if the current function uses the constant pool. */
189 int current_function_uses_const_pool;
191 /* Nonzero if the current function uses pic_offset_table_rtx. */
192 int current_function_uses_pic_offset_table;
194 /* The arg pointer hard register, or the pseudo into which it was copied. */
195 rtx current_function_internal_arg_pointer;
197 /* The FUNCTION_DECL for an inline function currently being expanded. */
198 tree inline_function_decl;
200 /* Number of function calls seen so far in current function. */
202 int function_call_count;
204 /* List (chain of TREE_LIST) of LABEL_DECLs for all nonlocal labels
205 (labels to which there can be nonlocal gotos from nested functions)
208 tree nonlocal_labels;
210 /* RTX for stack slot that holds the current handler for nonlocal gotos.
211 Zero when function does not have nonlocal labels. */
213 rtx nonlocal_goto_handler_slot;
215 /* RTX for stack slot that holds the stack pointer value to restore
217 Zero when function does not have nonlocal labels. */
219 rtx nonlocal_goto_stack_level;
221 /* Label that will go on parm cleanup code, if any.
222 Jumping to this label runs cleanup code for parameters, if
223 such code must be run. Following this code is the logical return label. */
227 /* Label that will go on function epilogue.
228 Jumping to this label serves as a "return" instruction
229 on machines which require execution of the epilogue on all returns. */
233 /* List (chain of EXPR_LISTs) of pseudo-regs of SAVE_EXPRs.
234 So we can mark them all live at the end of the function, if nonopt. */
237 /* List (chain of EXPR_LISTs) of all stack slots in this function.
238 Made for the sake of unshare_all_rtl. */
241 /* Chain of all RTL_EXPRs that have insns in them. */
244 /* Label to jump back to for tail recursion, or 0 if we have
245 not yet needed one for this function. */
246 rtx tail_recursion_label;
248 /* Place after which to insert the tail_recursion_label if we need one. */
249 rtx tail_recursion_reentry;
251 /* Location at which to save the argument pointer if it will need to be
252 referenced. There are two cases where this is done: if nonlocal gotos
253 exist, or if vars stored at an offset from the argument pointer will be
254 needed by inner routines. */
256 rtx arg_pointer_save_area;
258 /* Offset to end of allocated area of stack frame.
259 If stack grows down, this is the address of the last stack slot allocated.
260 If stack grows up, this is the address for the next slot. */
263 /* List (chain of TREE_LISTs) of static chains for containing functions.
264 Each link has a FUNCTION_DECL in the TREE_PURPOSE and a reg rtx
265 in an RTL_EXPR in the TREE_VALUE. */
266 static tree context_display;
268 /* List (chain of TREE_LISTs) of trampolines for nested functions.
269 The trampoline sets up the static chain and jumps to the function.
270 We supply the trampoline's address when the function's address is requested.
272 Each link has a FUNCTION_DECL in the TREE_PURPOSE and a reg rtx
273 in an RTL_EXPR in the TREE_VALUE. */
274 static tree trampoline_list;
276 /* Insn after which register parms and SAVE_EXPRs are born, if nonopt. */
277 static rtx parm_birth_insn;
280 /* Nonzero if a stack slot has been generated whose address is not
281 actually valid. It means that the generated rtl must all be scanned
282 to detect and correct the invalid addresses where they occur. */
283 static int invalid_stack_slot;
286 /* Last insn of those whose job was to put parms into their nominal homes. */
287 static rtx last_parm_insn;
289 /* 1 + last pseudo register number used for loading a copy
290 of a parameter of this function. */
291 static int max_parm_reg;
293 /* Vector indexed by REGNO, containing location on stack in which
294 to put the parm which is nominally in pseudo register REGNO,
295 if we discover that that parm must go in the stack. */
296 static rtx *parm_reg_stack_loc;
298 #if 0 /* Turned off because 0 seems to work just as well. */
299 /* Cleanup lists are required for binding levels regardless of whether
300 that binding level has cleanups or not. This node serves as the
301 cleanup list whenever an empty list is required. */
302 static tree empty_cleanup_list;
305 /* Nonzero once virtual register instantiation has been done.
306 assign_stack_local uses frame_pointer_rtx when this is nonzero. */
307 static int virtuals_instantiated;
309 /* These variables hold pointers to functions to
310 save and restore machine-specific data,
311 in push_function_context and pop_function_context. */
312 void (*save_machine_status) ();
313 void (*restore_machine_status) ();
315 /* Nonzero if we need to distinguish between the return value of this function
316 and the return value of a function called by this function. This helps
319 extern int rtx_equal_function_value_matters;
320 extern tree sequence_rtl_expr;
321 extern tree bc_runtime_type_code ();
322 extern rtx bc_build_calldesc ();
323 extern char *bc_emit_trampoline ();
324 extern char *bc_end_function ();
328 static tree round_down ();
329 static rtx round_trampoline_addr ();
330 static rtx fixup_stack_1 ();
331 static void put_reg_into_stack ();
332 static void fixup_var_refs ();
333 static void fixup_var_refs_insns ();
334 static void fixup_var_refs_1 ();
335 static void optimize_bit_field ();
336 static void instantiate_decls ();
337 static void instantiate_decls_1 ();
338 static void instantiate_decl ();
339 static int instantiate_virtual_regs_1 ();
340 static rtx fixup_memory_subreg ();
341 static rtx walk_fixup_memory_subreg ();
343 /* In order to evaluate some expressions, such as function calls returning
344 structures in memory, we need to temporarily allocate stack locations.
345 We record each allocated temporary in the following structure.
347 Associated with each temporary slot is a nesting level. When we pop up
348 one level, all temporaries associated with the previous level are freed.
349 Normally, all temporaries are freed after the execution of the statement
350 in which they were created. However, if we are inside a ({...}) grouping,
351 the result may be in a temporary and hence must be preserved. If the
352 result could be in a temporary, we preserve it if we can determine which
353 one it is in. If we cannot determine which temporary may contain the
354 result, all temporaries are preserved. A temporary is preserved by
355 pretending it was allocated at the previous nesting level.
357 Automatic variables are also assigned temporary slots, at the nesting
358 level where they are defined. They are marked a "kept" so that
359 free_temp_slots will not free them. */
363 /* Points to next temporary slot. */
364 struct temp_slot *next;
365 /* The rtx to used to reference the slot. */
367 /* The size, in units, of the slot. */
369 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
371 /* Non-zero if this temporary is currently in use. */
373 /* Nesting level at which this slot is being used. */
375 /* Non-zero if this should survive a call to free_temp_slots. */
379 /* List of all temporaries allocated, both available and in use. */
381 struct temp_slot *temp_slots;
383 /* Current nesting level for temporaries. */
387 /* The FUNCTION_DECL node for the current function. */
388 static tree this_function_decl;
390 /* Callinfo pointer for the current function. */
391 static rtx this_function_callinfo;
393 /* The label in the bytecode file of this function's actual bytecode.
395 static char *this_function_bytecode;
397 /* The call description vector for the current function. */
398 static rtx this_function_calldesc;
400 /* Size of the local variables allocated for the current function. */
403 /* Current depth of the bytecode evaluation stack. */
406 /* Maximum depth of the evaluation stack in this function. */
409 /* Current depth in statement expressions. */
410 static int stmt_expr_depth;
412 /* Pointer to chain of `struct function' for containing functions. */
413 struct function *outer_function_chain;
415 /* Given a function decl for a containing function,
416 return the `struct function' for it. */
419 find_function_data (decl)
423 for (p = outer_function_chain; p; p = p->next)
429 /* Save the current context for compilation of a nested function.
430 This is called from language-specific code.
431 The caller is responsible for saving any language-specific status,
432 since this function knows only about language-independent variables. */
435 push_function_context ()
437 struct function *p = (struct function *) xmalloc (sizeof (struct function));
439 p->next = outer_function_chain;
440 outer_function_chain = p;
442 p->name = current_function_name;
443 p->decl = current_function_decl;
444 p->pops_args = current_function_pops_args;
445 p->returns_struct = current_function_returns_struct;
446 p->returns_pcc_struct = current_function_returns_pcc_struct;
447 p->needs_context = current_function_needs_context;
448 p->calls_setjmp = current_function_calls_setjmp;
449 p->calls_longjmp = current_function_calls_longjmp;
450 p->calls_alloca = current_function_calls_alloca;
451 p->has_nonlocal_label = current_function_has_nonlocal_label;
452 p->has_nonlocal_goto = current_function_has_nonlocal_goto;
453 p->args_size = current_function_args_size;
454 p->pretend_args_size = current_function_pretend_args_size;
455 p->arg_offset_rtx = current_function_arg_offset_rtx;
456 p->uses_const_pool = current_function_uses_const_pool;
457 p->uses_pic_offset_table = current_function_uses_pic_offset_table;
458 p->internal_arg_pointer = current_function_internal_arg_pointer;
459 p->max_parm_reg = max_parm_reg;
460 p->parm_reg_stack_loc = parm_reg_stack_loc;
461 p->outgoing_args_size = current_function_outgoing_args_size;
462 p->return_rtx = current_function_return_rtx;
463 p->nonlocal_goto_handler_slot = nonlocal_goto_handler_slot;
464 p->nonlocal_goto_stack_level = nonlocal_goto_stack_level;
465 p->nonlocal_labels = nonlocal_labels;
466 p->cleanup_label = cleanup_label;
467 p->return_label = return_label;
468 p->save_expr_regs = save_expr_regs;
469 p->stack_slot_list = stack_slot_list;
470 p->parm_birth_insn = parm_birth_insn;
471 p->frame_offset = frame_offset;
472 p->tail_recursion_label = tail_recursion_label;
473 p->tail_recursion_reentry = tail_recursion_reentry;
474 p->arg_pointer_save_area = arg_pointer_save_area;
475 p->rtl_expr_chain = rtl_expr_chain;
476 p->last_parm_insn = last_parm_insn;
477 p->context_display = context_display;
478 p->trampoline_list = trampoline_list;
479 p->function_call_count = function_call_count;
480 p->temp_slots = temp_slots;
481 p->temp_slot_level = temp_slot_level;
482 p->fixup_var_refs_queue = 0;
483 p->epilogue_delay_list = current_function_epilogue_delay_list;
485 save_tree_status (p);
486 save_storage_status (p);
487 save_emit_status (p);
489 save_expr_status (p);
490 save_stmt_status (p);
491 save_varasm_status (p);
493 if (save_machine_status)
494 (*save_machine_status) (p);
497 /* Restore the last saved context, at the end of a nested function.
498 This function is called from language-specific code. */
501 pop_function_context ()
503 struct function *p = outer_function_chain;
505 outer_function_chain = p->next;
507 current_function_name = p->name;
508 current_function_decl = p->decl;
509 current_function_pops_args = p->pops_args;
510 current_function_returns_struct = p->returns_struct;
511 current_function_returns_pcc_struct = p->returns_pcc_struct;
512 current_function_needs_context = p->needs_context;
513 current_function_calls_setjmp = p->calls_setjmp;
514 current_function_calls_longjmp = p->calls_longjmp;
515 current_function_calls_alloca = p->calls_alloca;
516 current_function_has_nonlocal_label = p->has_nonlocal_label;
517 current_function_has_nonlocal_goto = p->has_nonlocal_goto;
518 current_function_contains_functions = 1;
519 current_function_args_size = p->args_size;
520 current_function_pretend_args_size = p->pretend_args_size;
521 current_function_arg_offset_rtx = p->arg_offset_rtx;
522 current_function_uses_const_pool = p->uses_const_pool;
523 current_function_uses_pic_offset_table = p->uses_pic_offset_table;
524 current_function_internal_arg_pointer = p->internal_arg_pointer;
525 max_parm_reg = p->max_parm_reg;
526 parm_reg_stack_loc = p->parm_reg_stack_loc;
527 current_function_outgoing_args_size = p->outgoing_args_size;
528 current_function_return_rtx = p->return_rtx;
529 nonlocal_goto_handler_slot = p->nonlocal_goto_handler_slot;
530 nonlocal_goto_stack_level = p->nonlocal_goto_stack_level;
531 nonlocal_labels = p->nonlocal_labels;
532 cleanup_label = p->cleanup_label;
533 return_label = p->return_label;
534 save_expr_regs = p->save_expr_regs;
535 stack_slot_list = p->stack_slot_list;
536 parm_birth_insn = p->parm_birth_insn;
537 frame_offset = p->frame_offset;
538 tail_recursion_label = p->tail_recursion_label;
539 tail_recursion_reentry = p->tail_recursion_reentry;
540 arg_pointer_save_area = p->arg_pointer_save_area;
541 rtl_expr_chain = p->rtl_expr_chain;
542 last_parm_insn = p->last_parm_insn;
543 context_display = p->context_display;
544 trampoline_list = p->trampoline_list;
545 function_call_count = p->function_call_count;
546 temp_slots = p->temp_slots;
547 temp_slot_level = p->temp_slot_level;
548 current_function_epilogue_delay_list = p->epilogue_delay_list;
550 restore_tree_status (p);
551 restore_storage_status (p);
552 restore_expr_status (p);
553 restore_emit_status (p);
554 restore_stmt_status (p);
555 restore_varasm_status (p);
557 if (restore_machine_status)
558 (*restore_machine_status) (p);
560 /* Finish doing put_var_into_stack for any of our variables
561 which became addressable during the nested function. */
563 struct var_refs_queue *queue = p->fixup_var_refs_queue;
564 for (; queue; queue = queue->next)
565 fixup_var_refs (queue->modified, queue->promoted_mode, queue->unsignedp);
570 /* Reset variables that have known state during rtx generation. */
571 rtx_equal_function_value_matters = 1;
572 virtuals_instantiated = 0;
575 /* Allocate fixed slots in the stack frame of the current function. */
577 /* Return size needed for stack frame based on slots so far allocated.
578 This size counts from zero. It is not rounded to STACK_BOUNDARY;
579 the caller may have to do that. */
584 #ifdef FRAME_GROWS_DOWNWARD
585 return -frame_offset;
591 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
592 with machine mode MODE.
594 ALIGN controls the amount of alignment for the address of the slot:
595 0 means according to MODE,
596 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
597 positive specifies alignment boundary in bits.
599 We do not round to stack_boundary here. */
602 assign_stack_local (mode, size, align)
603 enum machine_mode mode;
607 register rtx x, addr;
608 int bigend_correction = 0;
613 alignment = GET_MODE_ALIGNMENT (mode) / BITS_PER_UNIT;
615 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
617 else if (align == -1)
619 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
620 size = CEIL_ROUND (size, alignment);
623 alignment = align / BITS_PER_UNIT;
625 /* Round frame offset to that alignment.
626 We must be careful here, since FRAME_OFFSET might be negative and
627 division with a negative dividend isn't as well defined as we might
628 like. So we instead assume that ALIGNMENT is a power of two and
629 use logical operations which are unambiguous. */
630 #ifdef FRAME_GROWS_DOWNWARD
631 frame_offset = FLOOR_ROUND (frame_offset, alignment);
633 frame_offset = CEIL_ROUND (frame_offset, alignment);
636 /* On a big-endian machine, if we are allocating more space than we will use,
637 use the least significant bytes of those that are allocated. */
640 bigend_correction = size - GET_MODE_SIZE (mode);
643 #ifdef FRAME_GROWS_DOWNWARD
644 frame_offset -= size;
647 /* If we have already instantiated virtual registers, return the actual
648 address relative to the frame pointer. */
649 if (virtuals_instantiated)
650 addr = plus_constant (frame_pointer_rtx,
651 (frame_offset + bigend_correction
652 + STARTING_FRAME_OFFSET));
654 addr = plus_constant (virtual_stack_vars_rtx,
655 frame_offset + bigend_correction);
657 #ifndef FRAME_GROWS_DOWNWARD
658 frame_offset += size;
661 x = gen_rtx (MEM, mode, addr);
663 stack_slot_list = gen_rtx (EXPR_LIST, VOIDmode, x, stack_slot_list);
668 /* Assign a stack slot in a containing function.
669 First three arguments are same as in preceding function.
670 The last argument specifies the function to allocate in. */
673 assign_outer_stack_local (mode, size, align, function)
674 enum machine_mode mode;
677 struct function *function;
679 register rtx x, addr;
680 int bigend_correction = 0;
683 /* Allocate in the memory associated with the function in whose frame
685 push_obstacks (function->function_obstack,
686 function->function_maybepermanent_obstack);
690 alignment = GET_MODE_ALIGNMENT (mode) / BITS_PER_UNIT;
692 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
694 else if (align == -1)
696 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
697 size = CEIL_ROUND (size, alignment);
700 alignment = align / BITS_PER_UNIT;
702 /* Round frame offset to that alignment. */
703 #ifdef FRAME_GROWS_DOWNWARD
704 function->frame_offset = FLOOR_ROUND (function->frame_offset, alignment);
706 function->frame_offset = CEIL_ROUND (function->frame_offset, alignment);
709 /* On a big-endian machine, if we are allocating more space than we will use,
710 use the least significant bytes of those that are allocated. */
713 bigend_correction = size - GET_MODE_SIZE (mode);
716 #ifdef FRAME_GROWS_DOWNWARD
717 function->frame_offset -= size;
719 addr = plus_constant (virtual_stack_vars_rtx,
720 function->frame_offset + bigend_correction);
721 #ifndef FRAME_GROWS_DOWNWARD
722 function->frame_offset += size;
725 x = gen_rtx (MEM, mode, addr);
727 function->stack_slot_list
728 = gen_rtx (EXPR_LIST, VOIDmode, x, function->stack_slot_list);
735 /* Allocate a temporary stack slot and record it for possible later
738 MODE is the machine mode to be given to the returned rtx.
740 SIZE is the size in units of the space required. We do no rounding here
741 since assign_stack_local will do any required rounding.
743 KEEP is non-zero if this slot is to be retained after a call to
744 free_temp_slots. Automatic variables for a block are allocated with this
748 assign_stack_temp (mode, size, keep)
749 enum machine_mode mode;
753 struct temp_slot *p, *best_p = 0;
755 /* First try to find an available, already-allocated temporary that is the
756 exact size we require. */
757 for (p = temp_slots; p; p = p->next)
758 if (p->size == size && GET_MODE (p->slot) == mode && ! p->in_use)
761 /* If we didn't find, one, try one that is larger than what we want. We
762 find the smallest such. */
764 for (p = temp_slots; p; p = p->next)
765 if (p->size > size && GET_MODE (p->slot) == mode && ! p->in_use
766 && (best_p == 0 || best_p->size > p->size))
769 /* Make our best, if any, the one to use. */
772 /* If there are enough aligned bytes left over, make them into a new
773 temp_slot so that the extra bytes don't get wasted. Do this only
774 for BLKmode slots, so that we can be sure of the alignment. */
775 if (GET_MODE (best_p->slot) == BLKmode)
777 int alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
778 int rounded_size = CEIL_ROUND (size, alignment);
780 if (best_p->size - rounded_size >= alignment)
782 p = (struct temp_slot *) oballoc (sizeof (struct temp_slot));
784 p->size = best_p->size - rounded_size;
785 p->slot = gen_rtx (MEM, BLKmode,
786 plus_constant (XEXP (best_p->slot, 0),
788 p->next = temp_slots;
791 stack_slot_list = gen_rtx (EXPR_LIST, VOIDmode, p->slot,
794 best_p->size = rounded_size;
802 /* If we still didn't find one, make a new temporary. */
805 p = (struct temp_slot *) oballoc (sizeof (struct temp_slot));
807 /* If the temp slot mode doesn't indicate the alignment,
808 use the largest possible, so no one will be disappointed. */
809 p->slot = assign_stack_local (mode, size, mode == BLKmode ? -1 : 0);
810 p->next = temp_slots;
815 p->rtl_expr = sequence_rtl_expr;
816 p->level = temp_slot_level;
821 /* Combine temporary stack slots which are adjacent on the stack.
823 This allows for better use of already allocated stack space. This is only
824 done for BLKmode slots because we can be sure that we won't have alignment
825 problems in this case. */
828 combine_temp_slots ()
830 struct temp_slot *p, *q;
831 struct temp_slot *prev_p, *prev_q;
832 /* Determine where to free back to after this function. */
833 rtx free_pointer = rtx_alloc (CONST_INT);
835 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
838 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
839 for (q = p->next, prev_q = p; q; q = prev_q->next)
842 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
844 if (rtx_equal_p (plus_constant (XEXP (p->slot, 0), p->size),
847 /* Q comes after P; combine Q into P. */
851 else if (rtx_equal_p (plus_constant (XEXP (q->slot, 0), q->size),
854 /* P comes after Q; combine P into Q. */
860 /* Either delete Q or advance past it. */
862 prev_q->next = q->next;
866 /* Either delete P or advance past it. */
870 prev_p->next = p->next;
872 temp_slots = p->next;
878 /* Free all the RTL made by plus_constant. */
879 rtx_free (free_pointer);
882 /* If X could be a reference to a temporary slot, mark that slot as belonging
883 to the to one level higher. If X matched one of our slots, just mark that
884 one. Otherwise, we can't easily predict which it is, so upgrade all of
885 them. Kept slots need not be touched.
887 This is called when an ({...}) construct occurs and a statement
888 returns a value in memory. */
891 preserve_temp_slots (x)
896 /* If X is not in memory or is at a constant address, it cannot be in
898 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
901 /* First see if we can find a match. */
902 for (p = temp_slots; p; p = p->next)
903 if (p->in_use && x == p->slot)
909 /* Otherwise, preserve all non-kept slots at this level. */
910 for (p = temp_slots; p; p = p->next)
911 if (p->in_use && p->level == temp_slot_level && ! p->keep)
915 /* Free all temporaries used so far. This is normally called at the end
916 of generating code for a statement. Don't free any temporaries
917 currently in use for an RTL_EXPR that hasn't yet been emitted.
918 We could eventually do better than this since it can be reused while
919 generating the same RTL_EXPR, but this is complex and probably not
927 for (p = temp_slots; p; p = p->next)
928 if (p->in_use && p->level == temp_slot_level && ! p->keep
932 combine_temp_slots ();
935 /* Free all temporary slots used in T, an RTL_EXPR node. */
938 free_temps_for_rtl_expr (t)
943 for (p = temp_slots; p; p = p->next)
944 if (p->rtl_expr == t)
947 combine_temp_slots ();
950 /* Push deeper into the nesting level for stack temporaries. */
958 /* Pop a temporary nesting level. All slots in use in the current level
966 for (p = temp_slots; p; p = p->next)
967 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
970 combine_temp_slots ();
975 /* Retroactively move an auto variable from a register to a stack slot.
976 This is done when an address-reference to the variable is seen. */
979 put_var_into_stack (decl)
983 enum machine_mode promoted_mode, decl_mode;
984 struct function *function = 0;
990 context = decl_function_context (decl);
992 /* Get the current rtl used for this object and it's original mode. */
993 reg = TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl) : DECL_RTL (decl);
995 /* No need to do anything if decl has no rtx yet
996 since in that case caller is setting TREE_ADDRESSABLE
997 and a stack slot will be assigned when the rtl is made. */
1001 /* Get the declared mode for this object. */
1002 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1003 : DECL_MODE (decl));
1004 /* Get the mode it's actually stored in. */
1005 promoted_mode = GET_MODE (reg);
1007 /* If this variable comes from an outer function,
1008 find that function's saved context. */
1009 if (context != current_function_decl)
1010 for (function = outer_function_chain; function; function = function->next)
1011 if (function->decl == context)
1014 /* If this is a variable-size object with a pseudo to address it,
1015 put that pseudo into the stack, if the var is nonlocal. */
1016 if (DECL_NONLOCAL (decl)
1017 && GET_CODE (reg) == MEM
1018 && GET_CODE (XEXP (reg, 0)) == REG
1019 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1021 reg = XEXP (reg, 0);
1022 decl_mode = promoted_mode = GET_MODE (reg);
1025 /* Now we should have a value that resides in one or more pseudo regs. */
1027 if (GET_CODE (reg) == REG)
1028 put_reg_into_stack (function, reg, TREE_TYPE (decl),
1029 promoted_mode, decl_mode);
1030 else if (GET_CODE (reg) == CONCAT)
1032 /* A CONCAT contains two pseudos; put them both in the stack.
1033 We do it so they end up consecutive. */
1034 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1035 tree part_type = TREE_TYPE (TREE_TYPE (decl));
1036 #ifdef STACK_GROWS_DOWNWARD
1037 /* Since part 0 should have a lower address, do it second. */
1038 put_reg_into_stack (function, XEXP (reg, 1),
1039 part_type, part_mode, part_mode);
1040 put_reg_into_stack (function, XEXP (reg, 0),
1041 part_type, part_mode, part_mode);
1043 put_reg_into_stack (function, XEXP (reg, 0),
1044 part_type, part_mode, part_mode);
1045 put_reg_into_stack (function, XEXP (reg, 1),
1046 part_type, part_mode, part_mode);
1049 /* Change the CONCAT into a combined MEM for both parts. */
1050 PUT_CODE (reg, MEM);
1051 /* The two parts are in memory order already.
1052 Use the lower parts address as ours. */
1053 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1054 /* Prevent sharing of rtl that might lose. */
1055 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1056 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1060 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1061 into the stack frame of FUNCTION (0 means the current function).
1062 DECL_MODE is the machine mode of the user-level data type.
1063 PROMOTED_MODE is the machine mode of the register. */
1066 put_reg_into_stack (function, reg, type, promoted_mode, decl_mode)
1067 struct function *function;
1070 enum machine_mode promoted_mode, decl_mode;
1076 if (REGNO (reg) < function->max_parm_reg)
1077 new = function->parm_reg_stack_loc[REGNO (reg)];
1079 new = assign_outer_stack_local (decl_mode, GET_MODE_SIZE (decl_mode),
1084 if (REGNO (reg) < max_parm_reg)
1085 new = parm_reg_stack_loc[REGNO (reg)];
1087 new = assign_stack_local (decl_mode, GET_MODE_SIZE (decl_mode), 0);
1090 XEXP (reg, 0) = XEXP (new, 0);
1091 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1092 REG_USERVAR_P (reg) = 0;
1093 PUT_CODE (reg, MEM);
1094 PUT_MODE (reg, decl_mode);
1096 /* If this is a memory ref that contains aggregate components,
1097 mark it as such for cse and loop optimize. */
1098 MEM_IN_STRUCT_P (reg)
1099 = (TREE_CODE (type) == ARRAY_TYPE
1100 || TREE_CODE (type) == RECORD_TYPE
1101 || TREE_CODE (type) == UNION_TYPE
1102 || TREE_CODE (type) == QUAL_UNION_TYPE);
1104 /* Now make sure that all refs to the variable, previously made
1105 when it was a register, are fixed up to be valid again. */
1108 struct var_refs_queue *temp;
1110 /* Variable is inherited; fix it up when we get back to its function. */
1111 push_obstacks (function->function_obstack,
1112 function->function_maybepermanent_obstack);
1114 /* See comment in restore_tree_status in tree.c for why this needs to be
1115 on saveable obstack. */
1117 = (struct var_refs_queue *) savealloc (sizeof (struct var_refs_queue));
1118 temp->modified = reg;
1119 temp->promoted_mode = promoted_mode;
1120 temp->unsignedp = TREE_UNSIGNED (type);
1121 temp->next = function->fixup_var_refs_queue;
1122 function->fixup_var_refs_queue = temp;
1126 /* Variable is local; fix it up now. */
1127 fixup_var_refs (reg, promoted_mode, TREE_UNSIGNED (type));
1131 fixup_var_refs (var, promoted_mode, unsignedp)
1133 enum machine_mode promoted_mode;
1137 rtx first_insn = get_insns ();
1138 struct sequence_stack *stack = sequence_stack;
1139 tree rtl_exps = rtl_expr_chain;
1141 /* Must scan all insns for stack-refs that exceed the limit. */
1142 fixup_var_refs_insns (var, promoted_mode, unsignedp, first_insn, stack == 0);
1144 /* Scan all pending sequences too. */
1145 for (; stack; stack = stack->next)
1147 push_to_sequence (stack->first);
1148 fixup_var_refs_insns (var, promoted_mode, unsignedp,
1149 stack->first, stack->next != 0);
1150 /* Update remembered end of sequence
1151 in case we added an insn at the end. */
1152 stack->last = get_last_insn ();
1156 /* Scan all waiting RTL_EXPRs too. */
1157 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1159 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1160 if (seq != const0_rtx && seq != 0)
1162 push_to_sequence (seq);
1163 fixup_var_refs_insns (var, promoted_mode, unsignedp, seq, 0);
1169 /* This structure is used by the following two functions to record MEMs or
1170 pseudos used to replace VAR, any SUBREGs of VAR, and any MEMs containing
1171 VAR as an address. We need to maintain this list in case two operands of
1172 an insn were required to match; in that case we must ensure we use the
1173 same replacement. */
1175 struct fixup_replacement
1179 struct fixup_replacement *next;
1182 /* REPLACEMENTS is a pointer to a list of the above structures and X is
1183 some part of an insn. Return a struct fixup_replacement whose OLD
1184 value is equal to X. Allocate a new structure if no such entry exists. */
1186 static struct fixup_replacement *
1187 find_fixup_replacement (replacements, x)
1188 struct fixup_replacement **replacements;
1191 struct fixup_replacement *p;
1193 /* See if we have already replaced this. */
1194 for (p = *replacements; p && p->old != x; p = p->next)
1199 p = (struct fixup_replacement *) oballoc (sizeof (struct fixup_replacement));
1202 p->next = *replacements;
1209 /* Scan the insn-chain starting with INSN for refs to VAR
1210 and fix them up. TOPLEVEL is nonzero if this chain is the
1211 main chain of insns for the current function. */
1214 fixup_var_refs_insns (var, promoted_mode, unsignedp, insn, toplevel)
1216 enum machine_mode promoted_mode;
1225 rtx next = NEXT_INSN (insn);
1227 if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
1229 /* The insn to load VAR from a home in the arglist
1230 is now a no-op. When we see it, just delete it. */
1232 && GET_CODE (PATTERN (insn)) == SET
1233 && SET_DEST (PATTERN (insn)) == var
1234 /* If this represents the result of an insn group,
1235 don't delete the insn. */
1236 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1237 && rtx_equal_p (SET_SRC (PATTERN (insn)), var))
1239 /* In unoptimized compilation, we shouldn't call delete_insn
1240 except in jump.c doing warnings. */
1241 PUT_CODE (insn, NOTE);
1242 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1243 NOTE_SOURCE_FILE (insn) = 0;
1244 if (insn == last_parm_insn)
1245 last_parm_insn = PREV_INSN (next);
1249 struct fixup_replacement *replacements = 0;
1250 rtx next_insn = NEXT_INSN (insn);
1252 #ifdef SMALL_REGISTER_CLASSES
1253 /* If the insn that copies the results of a CALL_INSN
1254 into a pseudo now references VAR, we have to use an
1255 intermediate pseudo since we want the life of the
1256 return value register to be only a single insn.
1258 If we don't use an intermediate pseudo, such things as
1259 address computations to make the address of VAR valid
1260 if it is not can be placed beween the CALL_INSN and INSN.
1262 To make sure this doesn't happen, we record the destination
1263 of the CALL_INSN and see if the next insn uses both that
1266 if (call_dest != 0 && GET_CODE (insn) == INSN
1267 && reg_mentioned_p (var, PATTERN (insn))
1268 && reg_mentioned_p (call_dest, PATTERN (insn)))
1270 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1272 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1274 PATTERN (insn) = replace_rtx (PATTERN (insn),
1278 if (GET_CODE (insn) == CALL_INSN
1279 && GET_CODE (PATTERN (insn)) == SET)
1280 call_dest = SET_DEST (PATTERN (insn));
1281 else if (GET_CODE (insn) == CALL_INSN
1282 && GET_CODE (PATTERN (insn)) == PARALLEL
1283 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1284 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1289 /* See if we have to do anything to INSN now that VAR is in
1290 memory. If it needs to be loaded into a pseudo, use a single
1291 pseudo for the entire insn in case there is a MATCH_DUP
1292 between two operands. We pass a pointer to the head of
1293 a list of struct fixup_replacements. If fixup_var_refs_1
1294 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1295 it will record them in this list.
1297 If it allocated a pseudo for any replacement, we copy into
1300 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1303 /* If this is last_parm_insn, and any instructions were output
1304 after it to fix it up, then we must set last_parm_insn to
1305 the last such instruction emitted. */
1306 if (insn == last_parm_insn)
1307 last_parm_insn = PREV_INSN (next_insn);
1309 while (replacements)
1311 if (GET_CODE (replacements->new) == REG)
1316 /* OLD might be a (subreg (mem)). */
1317 if (GET_CODE (replacements->old) == SUBREG)
1319 = fixup_memory_subreg (replacements->old, insn, 0);
1322 = fixup_stack_1 (replacements->old, insn);
1324 /* We can not separate USE insns from the CALL_INSN
1325 that they belong to. If this is a CALL_INSN, insert
1326 the move insn before the USE insns preceding it
1327 instead of immediately before the insn. */
1328 if (GET_CODE (insn) == CALL_INSN)
1330 insert_before = insn;
1331 while (GET_CODE (PREV_INSN (insert_before)) == INSN
1332 && GET_CODE (PATTERN (PREV_INSN (insert_before))) == USE)
1333 insert_before = PREV_INSN (insert_before);
1336 insert_before = insn;
1338 /* If we are changing the mode, do a conversion.
1339 This might be wasteful, but combine.c will
1340 eliminate much of the waste. */
1342 if (GET_MODE (replacements->new)
1343 != GET_MODE (replacements->old))
1346 convert_move (replacements->new,
1347 replacements->old, unsignedp);
1348 seq = gen_sequence ();
1352 seq = gen_move_insn (replacements->new,
1355 emit_insn_before (seq, insert_before);
1358 replacements = replacements->next;
1362 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1363 But don't touch other insns referred to by reg-notes;
1364 we will get them elsewhere. */
1365 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
1366 if (GET_CODE (note) != INSN_LIST)
1368 = walk_fixup_memory_subreg (XEXP (note, 0), insn, 1);
1374 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1375 See if the rtx expression at *LOC in INSN needs to be changed.
1377 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1378 contain a list of original rtx's and replacements. If we find that we need
1379 to modify this insn by replacing a memory reference with a pseudo or by
1380 making a new MEM to implement a SUBREG, we consult that list to see if
1381 we have already chosen a replacement. If none has already been allocated,
1382 we allocate it and update the list. fixup_var_refs_insns will copy VAR
1383 or the SUBREG, as appropriate, to the pseudo. */
1386 fixup_var_refs_1 (var, promoted_mode, loc, insn, replacements)
1388 enum machine_mode promoted_mode;
1391 struct fixup_replacement **replacements;
1394 register rtx x = *loc;
1395 RTX_CODE code = GET_CODE (x);
1397 register rtx tem, tem1;
1398 struct fixup_replacement *replacement;
1405 /* If we already have a replacement, use it. Otherwise,
1406 try to fix up this address in case it is invalid. */
1408 replacement = find_fixup_replacement (replacements, var);
1409 if (replacement->new)
1411 *loc = replacement->new;
1415 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1417 /* Unless we are forcing memory to register or we changed the mode,
1418 we can leave things the way they are if the insn is valid. */
1420 INSN_CODE (insn) = -1;
1421 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1422 && recog_memoized (insn) >= 0)
1425 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1429 /* If X contains VAR, we need to unshare it here so that we update
1430 each occurrence separately. But all identical MEMs in one insn
1431 must be replaced with the same rtx because of the possibility of
1434 if (reg_mentioned_p (var, x))
1436 replacement = find_fixup_replacement (replacements, x);
1437 if (replacement->new == 0)
1438 replacement->new = copy_most_rtx (x, var);
1440 *loc = x = replacement->new;
1456 /* Note that in some cases those types of expressions are altered
1457 by optimize_bit_field, and do not survive to get here. */
1458 if (XEXP (x, 0) == var
1459 || (GET_CODE (XEXP (x, 0)) == SUBREG
1460 && SUBREG_REG (XEXP (x, 0)) == var))
1462 /* Get TEM as a valid MEM in the mode presently in the insn.
1464 We don't worry about the possibility of MATCH_DUP here; it
1465 is highly unlikely and would be tricky to handle. */
1468 if (GET_CODE (tem) == SUBREG)
1469 tem = fixup_memory_subreg (tem, insn, 1);
1470 tem = fixup_stack_1 (tem, insn);
1472 /* Unless we want to load from memory, get TEM into the proper mode
1473 for an extract from memory. This can only be done if the
1474 extract is at a constant position and length. */
1476 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
1477 && GET_CODE (XEXP (x, 2)) == CONST_INT
1478 && ! mode_dependent_address_p (XEXP (tem, 0))
1479 && ! MEM_VOLATILE_P (tem))
1481 enum machine_mode wanted_mode = VOIDmode;
1482 enum machine_mode is_mode = GET_MODE (tem);
1483 int width = INTVAL (XEXP (x, 1));
1484 int pos = INTVAL (XEXP (x, 2));
1487 if (GET_CODE (x) == ZERO_EXTRACT)
1488 wanted_mode = insn_operand_mode[(int) CODE_FOR_extzv][1];
1491 if (GET_CODE (x) == SIGN_EXTRACT)
1492 wanted_mode = insn_operand_mode[(int) CODE_FOR_extv][1];
1494 /* If we have a narrower mode, we can do something. */
1495 if (wanted_mode != VOIDmode
1496 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
1498 int offset = pos / BITS_PER_UNIT;
1499 rtx old_pos = XEXP (x, 2);
1502 /* If the bytes and bits are counted differently, we
1503 must adjust the offset. */
1504 #if BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN
1505 offset = (GET_MODE_SIZE (is_mode)
1506 - GET_MODE_SIZE (wanted_mode) - offset);
1509 pos %= GET_MODE_BITSIZE (wanted_mode);
1511 newmem = gen_rtx (MEM, wanted_mode,
1512 plus_constant (XEXP (tem, 0), offset));
1513 RTX_UNCHANGING_P (newmem) = RTX_UNCHANGING_P (tem);
1514 MEM_VOLATILE_P (newmem) = MEM_VOLATILE_P (tem);
1515 MEM_IN_STRUCT_P (newmem) = MEM_IN_STRUCT_P (tem);
1517 /* Make the change and see if the insn remains valid. */
1518 INSN_CODE (insn) = -1;
1519 XEXP (x, 0) = newmem;
1520 XEXP (x, 2) = GEN_INT (pos);
1522 if (recog_memoized (insn) >= 0)
1525 /* Otherwise, restore old position. XEXP (x, 0) will be
1527 XEXP (x, 2) = old_pos;
1531 /* If we get here, the bitfield extract insn can't accept a memory
1532 reference. Copy the input into a register. */
1534 tem1 = gen_reg_rtx (GET_MODE (tem));
1535 emit_insn_before (gen_move_insn (tem1, tem), insn);
1542 if (SUBREG_REG (x) == var)
1544 /* If this is a special SUBREG made because VAR was promoted
1545 from a wider mode, replace it with VAR and call ourself
1546 recursively, this time saying that the object previously
1547 had its current mode (by virtue of the SUBREG). */
1549 if (SUBREG_PROMOTED_VAR_P (x))
1552 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements);
1556 /* If this SUBREG makes VAR wider, it has become a paradoxical
1557 SUBREG with VAR in memory, but these aren't allowed at this
1558 stage of the compilation. So load VAR into a pseudo and take
1559 a SUBREG of that pseudo. */
1560 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
1562 replacement = find_fixup_replacement (replacements, var);
1563 if (replacement->new == 0)
1564 replacement->new = gen_reg_rtx (GET_MODE (var));
1565 SUBREG_REG (x) = replacement->new;
1569 /* See if we have already found a replacement for this SUBREG.
1570 If so, use it. Otherwise, make a MEM and see if the insn
1571 is recognized. If not, or if we should force MEM into a register,
1572 make a pseudo for this SUBREG. */
1573 replacement = find_fixup_replacement (replacements, x);
1574 if (replacement->new)
1576 *loc = replacement->new;
1580 replacement->new = *loc = fixup_memory_subreg (x, insn, 0);
1582 INSN_CODE (insn) = -1;
1583 if (! flag_force_mem && recog_memoized (insn) >= 0)
1586 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
1592 /* First do special simplification of bit-field references. */
1593 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
1594 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
1595 optimize_bit_field (x, insn, 0);
1596 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
1597 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
1598 optimize_bit_field (x, insn, NULL_PTR);
1600 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
1601 insn into a pseudo and store the low part of the pseudo into VAR. */
1602 if (GET_CODE (SET_DEST (x)) == SUBREG
1603 && SUBREG_REG (SET_DEST (x)) == var
1604 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
1605 > GET_MODE_SIZE (GET_MODE (var))))
1607 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
1608 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
1615 rtx dest = SET_DEST (x);
1616 rtx src = SET_SRC (x);
1617 rtx outerdest = dest;
1619 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
1620 || GET_CODE (dest) == SIGN_EXTRACT
1621 || GET_CODE (dest) == ZERO_EXTRACT)
1622 dest = XEXP (dest, 0);
1624 if (GET_CODE (src) == SUBREG)
1625 src = XEXP (src, 0);
1627 /* If VAR does not appear at the top level of the SET
1628 just scan the lower levels of the tree. */
1630 if (src != var && dest != var)
1633 /* We will need to rerecognize this insn. */
1634 INSN_CODE (insn) = -1;
1637 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var)
1639 /* Since this case will return, ensure we fixup all the
1641 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
1642 insn, replacements);
1643 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
1644 insn, replacements);
1645 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
1646 insn, replacements);
1648 tem = XEXP (outerdest, 0);
1650 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
1651 that may appear inside a ZERO_EXTRACT.
1652 This was legitimate when the MEM was a REG. */
1653 if (GET_CODE (tem) == SUBREG
1654 && SUBREG_REG (tem) == var)
1655 tem = fixup_memory_subreg (tem, insn, 1);
1657 tem = fixup_stack_1 (tem, insn);
1659 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
1660 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
1661 && ! mode_dependent_address_p (XEXP (tem, 0))
1662 && ! MEM_VOLATILE_P (tem))
1664 enum machine_mode wanted_mode
1665 = insn_operand_mode[(int) CODE_FOR_insv][0];
1666 enum machine_mode is_mode = GET_MODE (tem);
1667 int width = INTVAL (XEXP (outerdest, 1));
1668 int pos = INTVAL (XEXP (outerdest, 2));
1670 /* If we have a narrower mode, we can do something. */
1671 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
1673 int offset = pos / BITS_PER_UNIT;
1674 rtx old_pos = XEXP (outerdest, 2);
1677 #if BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN
1678 offset = (GET_MODE_SIZE (is_mode)
1679 - GET_MODE_SIZE (wanted_mode) - offset);
1682 pos %= GET_MODE_BITSIZE (wanted_mode);
1684 newmem = gen_rtx (MEM, wanted_mode,
1685 plus_constant (XEXP (tem, 0), offset));
1686 RTX_UNCHANGING_P (newmem) = RTX_UNCHANGING_P (tem);
1687 MEM_VOLATILE_P (newmem) = MEM_VOLATILE_P (tem);
1688 MEM_IN_STRUCT_P (newmem) = MEM_IN_STRUCT_P (tem);
1690 /* Make the change and see if the insn remains valid. */
1691 INSN_CODE (insn) = -1;
1692 XEXP (outerdest, 0) = newmem;
1693 XEXP (outerdest, 2) = GEN_INT (pos);
1695 if (recog_memoized (insn) >= 0)
1698 /* Otherwise, restore old position. XEXP (x, 0) will be
1700 XEXP (outerdest, 2) = old_pos;
1704 /* If we get here, the bit-field store doesn't allow memory
1705 or isn't located at a constant position. Load the value into
1706 a register, do the store, and put it back into memory. */
1708 tem1 = gen_reg_rtx (GET_MODE (tem));
1709 emit_insn_before (gen_move_insn (tem1, tem), insn);
1710 emit_insn_after (gen_move_insn (tem, tem1), insn);
1711 XEXP (outerdest, 0) = tem1;
1716 /* STRICT_LOW_PART is a no-op on memory references
1717 and it can cause combinations to be unrecognizable,
1720 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
1721 SET_DEST (x) = XEXP (SET_DEST (x), 0);
1723 /* A valid insn to copy VAR into or out of a register
1724 must be left alone, to avoid an infinite loop here.
1725 If the reference to VAR is by a subreg, fix that up,
1726 since SUBREG is not valid for a memref.
1727 Also fix up the address of the stack slot.
1729 Note that we must not try to recognize the insn until
1730 after we know that we have valid addresses and no
1731 (subreg (mem ...) ...) constructs, since these interfere
1732 with determining the validity of the insn. */
1734 if ((SET_SRC (x) == var
1735 || (GET_CODE (SET_SRC (x)) == SUBREG
1736 && SUBREG_REG (SET_SRC (x)) == var))
1737 && (GET_CODE (SET_DEST (x)) == REG
1738 || (GET_CODE (SET_DEST (x)) == SUBREG
1739 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
1740 && x == single_set (PATTERN (insn)))
1744 replacement = find_fixup_replacement (replacements, SET_SRC (x));
1745 if (replacement->new)
1746 SET_SRC (x) = replacement->new;
1747 else if (GET_CODE (SET_SRC (x)) == SUBREG)
1748 SET_SRC (x) = replacement->new
1749 = fixup_memory_subreg (SET_SRC (x), insn, 0);
1751 SET_SRC (x) = replacement->new
1752 = fixup_stack_1 (SET_SRC (x), insn);
1754 if (recog_memoized (insn) >= 0)
1757 /* INSN is not valid, but we know that we want to
1758 copy SET_SRC (x) to SET_DEST (x) in some way. So
1759 we generate the move and see whether it requires more
1760 than one insn. If it does, we emit those insns and
1761 delete INSN. Otherwise, we an just replace the pattern
1762 of INSN; we have already verified above that INSN has
1763 no other function that to do X. */
1765 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
1766 if (GET_CODE (pat) == SEQUENCE)
1768 emit_insn_after (pat, insn);
1769 PUT_CODE (insn, NOTE);
1770 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1771 NOTE_SOURCE_FILE (insn) = 0;
1774 PATTERN (insn) = pat;
1779 if ((SET_DEST (x) == var
1780 || (GET_CODE (SET_DEST (x)) == SUBREG
1781 && SUBREG_REG (SET_DEST (x)) == var))
1782 && (GET_CODE (SET_SRC (x)) == REG
1783 || (GET_CODE (SET_SRC (x)) == SUBREG
1784 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
1785 && x == single_set (PATTERN (insn)))
1789 if (GET_CODE (SET_DEST (x)) == SUBREG)
1790 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn, 0);
1792 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
1794 if (recog_memoized (insn) >= 0)
1797 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
1798 if (GET_CODE (pat) == SEQUENCE)
1800 emit_insn_after (pat, insn);
1801 PUT_CODE (insn, NOTE);
1802 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1803 NOTE_SOURCE_FILE (insn) = 0;
1806 PATTERN (insn) = pat;
1811 /* Otherwise, storing into VAR must be handled specially
1812 by storing into a temporary and copying that into VAR
1813 with a new insn after this one. Note that this case
1814 will be used when storing into a promoted scalar since
1815 the insn will now have different modes on the input
1816 and output and hence will be invalid (except for the case
1817 of setting it to a constant, which does not need any
1818 change if it is valid). We generate extra code in that case,
1819 but combine.c will eliminate it. */
1824 rtx fixeddest = SET_DEST (x);
1826 /* STRICT_LOW_PART can be discarded, around a MEM. */
1827 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
1828 fixeddest = XEXP (fixeddest, 0);
1829 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
1830 if (GET_CODE (fixeddest) == SUBREG)
1831 fixeddest = fixup_memory_subreg (fixeddest, insn, 0);
1833 fixeddest = fixup_stack_1 (fixeddest, insn);
1835 temp = gen_reg_rtx (GET_MODE (SET_SRC (x)) == VOIDmode
1836 ? GET_MODE (fixeddest)
1837 : GET_MODE (SET_SRC (x)));
1839 emit_insn_after (gen_move_insn (fixeddest,
1840 gen_lowpart (GET_MODE (fixeddest),
1844 SET_DEST (x) = temp;
1849 /* Nothing special about this RTX; fix its operands. */
1851 fmt = GET_RTX_FORMAT (code);
1852 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
1855 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements);
1859 for (j = 0; j < XVECLEN (x, i); j++)
1860 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
1861 insn, replacements);
1866 /* Given X, an rtx of the form (SUBREG:m1 (MEM:m2 addr)),
1867 return an rtx (MEM:m1 newaddr) which is equivalent.
1868 If any insns must be emitted to compute NEWADDR, put them before INSN.
1870 UNCRITICAL nonzero means accept paradoxical subregs.
1871 This is used for subregs found inside of ZERO_EXTRACTs and in REG_NOTES. */
1874 fixup_memory_subreg (x, insn, uncritical)
1879 int offset = SUBREG_WORD (x) * UNITS_PER_WORD;
1880 rtx addr = XEXP (SUBREG_REG (x), 0);
1881 enum machine_mode mode = GET_MODE (x);
1884 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
1885 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))
1889 #if BYTES_BIG_ENDIAN
1890 offset += (MIN (UNITS_PER_WORD, GET_MODE_SIZE (GET_MODE (SUBREG_REG (x))))
1891 - MIN (UNITS_PER_WORD, GET_MODE_SIZE (mode)));
1893 addr = plus_constant (addr, offset);
1894 if (!flag_force_addr && memory_address_p (mode, addr))
1895 /* Shortcut if no insns need be emitted. */
1896 return change_address (SUBREG_REG (x), mode, addr);
1898 result = change_address (SUBREG_REG (x), mode, addr);
1899 emit_insn_before (gen_sequence (), insn);
1904 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
1905 Replace subexpressions of X in place.
1906 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
1907 Otherwise return X, with its contents possibly altered.
1909 If any insns must be emitted to compute NEWADDR, put them before INSN.
1911 UNCRITICAL is as in fixup_memory_subreg. */
1914 walk_fixup_memory_subreg (x, insn, uncritical)
1919 register enum rtx_code code;
1926 code = GET_CODE (x);
1928 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
1929 return fixup_memory_subreg (x, insn, uncritical);
1931 /* Nothing special about this RTX; fix its operands. */
1933 fmt = GET_RTX_FORMAT (code);
1934 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
1937 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn, uncritical);
1941 for (j = 0; j < XVECLEN (x, i); j++)
1943 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn, uncritical);
1950 /* Fix up any references to stack slots that are invalid memory addresses
1951 because they exceed the maximum range of a displacement. */
1954 fixup_stack_slots ()
1958 /* Did we generate a stack slot that is out of range
1959 or otherwise has an invalid address? */
1960 if (invalid_stack_slot)
1962 /* Yes. Must scan all insns for stack-refs that exceed the limit. */
1963 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
1964 if (GET_CODE (insn) == INSN || GET_CODE (insn) == CALL_INSN
1965 || GET_CODE (insn) == JUMP_INSN)
1966 fixup_stack_1 (PATTERN (insn), insn);
1971 /* For each memory ref within X, if it refers to a stack slot
1972 with an out of range displacement, put the address in a temp register
1973 (emitting new insns before INSN to load these registers)
1974 and alter the memory ref to use that register.
1975 Replace each such MEM rtx with a copy, to avoid clobberage. */
1978 fixup_stack_1 (x, insn)
1983 register RTX_CODE code = GET_CODE (x);
1988 register rtx ad = XEXP (x, 0);
1989 /* If we have address of a stack slot but it's not valid
1990 (displacement is too large), compute the sum in a register. */
1991 if (GET_CODE (ad) == PLUS
1992 && GET_CODE (XEXP (ad, 0)) == REG
1993 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
1994 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
1995 || XEXP (ad, 0) == current_function_internal_arg_pointer)
1996 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
1999 if (memory_address_p (GET_MODE (x), ad))
2003 temp = copy_to_reg (ad);
2004 seq = gen_sequence ();
2006 emit_insn_before (seq, insn);
2007 return change_address (x, VOIDmode, temp);
2012 fmt = GET_RTX_FORMAT (code);
2013 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2016 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2020 for (j = 0; j < XVECLEN (x, i); j++)
2021 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2027 /* Optimization: a bit-field instruction whose field
2028 happens to be a byte or halfword in memory
2029 can be changed to a move instruction.
2031 We call here when INSN is an insn to examine or store into a bit-field.
2032 BODY is the SET-rtx to be altered.
2034 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2035 (Currently this is called only from function.c, and EQUIV_MEM
2039 optimize_bit_field (body, insn, equiv_mem)
2044 register rtx bitfield;
2047 enum machine_mode mode;
2049 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2050 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2051 bitfield = SET_DEST (body), destflag = 1;
2053 bitfield = SET_SRC (body), destflag = 0;
2055 /* First check that the field being stored has constant size and position
2056 and is in fact a byte or halfword suitably aligned. */
2058 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2059 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2060 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2062 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2064 register rtx memref = 0;
2066 /* Now check that the containing word is memory, not a register,
2067 and that it is safe to change the machine mode. */
2069 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2070 memref = XEXP (bitfield, 0);
2071 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2073 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2074 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2075 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2076 memref = SUBREG_REG (XEXP (bitfield, 0));
2077 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2079 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2080 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2083 && ! mode_dependent_address_p (XEXP (memref, 0))
2084 && ! MEM_VOLATILE_P (memref))
2086 /* Now adjust the address, first for any subreg'ing
2087 that we are now getting rid of,
2088 and then for which byte of the word is wanted. */
2090 register int offset = INTVAL (XEXP (bitfield, 2));
2091 /* Adjust OFFSET to count bits from low-address byte. */
2092 #if BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN
2093 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2094 - offset - INTVAL (XEXP (bitfield, 1)));
2096 /* Adjust OFFSET to count bytes from low-address byte. */
2097 offset /= BITS_PER_UNIT;
2098 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2100 offset += SUBREG_WORD (XEXP (bitfield, 0)) * UNITS_PER_WORD;
2101 #if BYTES_BIG_ENDIAN
2102 offset -= (MIN (UNITS_PER_WORD,
2103 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2104 - MIN (UNITS_PER_WORD,
2105 GET_MODE_SIZE (GET_MODE (memref))));
2109 memref = change_address (memref, mode,
2110 plus_constant (XEXP (memref, 0), offset));
2112 /* Store this memory reference where
2113 we found the bit field reference. */
2117 validate_change (insn, &SET_DEST (body), memref, 1);
2118 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2120 rtx src = SET_SRC (body);
2121 while (GET_CODE (src) == SUBREG
2122 && SUBREG_WORD (src) == 0)
2123 src = SUBREG_REG (src);
2124 if (GET_MODE (src) != GET_MODE (memref))
2125 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2126 validate_change (insn, &SET_SRC (body), src, 1);
2128 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2129 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2130 /* This shouldn't happen because anything that didn't have
2131 one of these modes should have got converted explicitly
2132 and then referenced through a subreg.
2133 This is so because the original bit-field was
2134 handled by agg_mode and so its tree structure had
2135 the same mode that memref now has. */
2140 rtx dest = SET_DEST (body);
2142 while (GET_CODE (dest) == SUBREG
2143 && SUBREG_WORD (dest) == 0)
2144 dest = SUBREG_REG (dest);
2146 validate_change (insn, &SET_DEST (body), dest, 1);
2148 if (GET_MODE (dest) == GET_MODE (memref))
2149 validate_change (insn, &SET_SRC (body), memref, 1);
2152 /* Convert the mem ref to the destination mode. */
2153 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2156 convert_move (newreg, memref,
2157 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2161 validate_change (insn, &SET_SRC (body), newreg, 1);
2165 /* See if we can convert this extraction or insertion into
2166 a simple move insn. We might not be able to do so if this
2167 was, for example, part of a PARALLEL.
2169 If we succeed, write out any needed conversions. If we fail,
2170 it is hard to guess why we failed, so don't do anything
2171 special; just let the optimization be suppressed. */
2173 if (apply_change_group () && seq)
2174 emit_insns_before (seq, insn);
2179 /* These routines are responsible for converting virtual register references
2180 to the actual hard register references once RTL generation is complete.
2182 The following four variables are used for communication between the
2183 routines. They contain the offsets of the virtual registers from their
2184 respective hard registers. */
2186 static int in_arg_offset;
2187 static int var_offset;
2188 static int dynamic_offset;
2189 static int out_arg_offset;
2191 /* In most machines, the stack pointer register is equivalent to the bottom
2194 #ifndef STACK_POINTER_OFFSET
2195 #define STACK_POINTER_OFFSET 0
2198 /* If not defined, pick an appropriate default for the offset of dynamically
2199 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2200 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2202 #ifndef STACK_DYNAMIC_OFFSET
2204 #ifdef ACCUMULATE_OUTGOING_ARGS
2205 /* The bottom of the stack points to the actual arguments. If
2206 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2207 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2208 stack space for register parameters is not pushed by the caller, but
2209 rather part of the fixed stack areas and hence not included in
2210 `current_function_outgoing_args_size'. Nevertheless, we must allow
2211 for it when allocating stack dynamic objects. */
2213 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2214 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2215 (current_function_outgoing_args_size \
2216 + REG_PARM_STACK_SPACE (FNDECL) + (STACK_POINTER_OFFSET))
2219 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2220 (current_function_outgoing_args_size + (STACK_POINTER_OFFSET))
2224 #define STACK_DYNAMIC_OFFSET(FNDECL) STACK_POINTER_OFFSET
2228 /* Pass through the INSNS of function FNDECL and convert virtual register
2229 references to hard register references. */
2232 instantiate_virtual_regs (fndecl, insns)
2238 /* Compute the offsets to use for this function. */
2239 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
2240 var_offset = STARTING_FRAME_OFFSET;
2241 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
2242 out_arg_offset = STACK_POINTER_OFFSET;
2244 /* Scan all variables and parameters of this function. For each that is
2245 in memory, instantiate all virtual registers if the result is a valid
2246 address. If not, we do it later. That will handle most uses of virtual
2247 regs on many machines. */
2248 instantiate_decls (fndecl, 1);
2250 /* Initialize recognition, indicating that volatile is OK. */
2253 /* Scan through all the insns, instantiating every virtual register still
2255 for (insn = insns; insn; insn = NEXT_INSN (insn))
2256 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
2257 || GET_CODE (insn) == CALL_INSN)
2259 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
2260 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
2263 /* Now instantiate the remaining register equivalences for debugging info.
2264 These will not be valid addresses. */
2265 instantiate_decls (fndecl, 0);
2267 /* Indicate that, from now on, assign_stack_local should use
2268 frame_pointer_rtx. */
2269 virtuals_instantiated = 1;
2272 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
2273 all virtual registers in their DECL_RTL's.
2275 If VALID_ONLY, do this only if the resulting address is still valid.
2276 Otherwise, always do it. */
2279 instantiate_decls (fndecl, valid_only)
2285 if (DECL_INLINE (fndecl))
2286 /* When compiling an inline function, the obstack used for
2287 rtl allocation is the maybepermanent_obstack. Calling
2288 `resume_temporary_allocation' switches us back to that
2289 obstack while we process this function's parameters. */
2290 resume_temporary_allocation ();
2292 /* Process all parameters of the function. */
2293 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
2295 instantiate_decl (DECL_RTL (decl), int_size_in_bytes (TREE_TYPE (decl)),
2297 instantiate_decl (DECL_INCOMING_RTL (decl),
2298 int_size_in_bytes (TREE_TYPE (decl)), valid_only);
2301 /* Now process all variables defined in the function or its subblocks. */
2302 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
2304 if (DECL_INLINE (fndecl))
2306 /* Save all rtl allocated for this function by raising the
2307 high-water mark on the maybepermanent_obstack. */
2309 /* All further rtl allocation is now done in the current_obstack. */
2310 rtl_in_current_obstack ();
2314 /* Subroutine of instantiate_decls: Process all decls in the given
2315 BLOCK node and all its subblocks. */
2318 instantiate_decls_1 (let, valid_only)
2324 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
2325 instantiate_decl (DECL_RTL (t), int_size_in_bytes (TREE_TYPE (t)),
2328 /* Process all subblocks. */
2329 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
2330 instantiate_decls_1 (t, valid_only);
2333 /* Subroutine of the preceding procedures: Given RTL representing a
2334 decl and the size of the object, do any instantiation required.
2336 If VALID_ONLY is non-zero, it means that the RTL should only be
2337 changed if the new address is valid. */
2340 instantiate_decl (x, size, valid_only)
2345 enum machine_mode mode;
2348 /* If this is not a MEM, no need to do anything. Similarly if the
2349 address is a constant or a register that is not a virtual register. */
2351 if (x == 0 || GET_CODE (x) != MEM)
2355 if (CONSTANT_P (addr)
2356 || (GET_CODE (addr) == REG
2357 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
2358 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
2361 /* If we should only do this if the address is valid, copy the address.
2362 We need to do this so we can undo any changes that might make the
2363 address invalid. This copy is unfortunate, but probably can't be
2367 addr = copy_rtx (addr);
2369 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
2374 /* Now verify that the resulting address is valid for every integer or
2375 floating-point mode up to and including SIZE bytes long. We do this
2376 since the object might be accessed in any mode and frame addresses
2379 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
2380 mode != VOIDmode && GET_MODE_SIZE (mode) <= size;
2381 mode = GET_MODE_WIDER_MODE (mode))
2382 if (! memory_address_p (mode, addr))
2385 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
2386 mode != VOIDmode && GET_MODE_SIZE (mode) <= size;
2387 mode = GET_MODE_WIDER_MODE (mode))
2388 if (! memory_address_p (mode, addr))
2391 /* Otherwise, put back the address, now that we have updated it and we
2392 know it is valid. */
2397 /* Given a pointer to a piece of rtx and an optional pointer to the
2398 containing object, instantiate any virtual registers present in it.
2400 If EXTRA_INSNS, we always do the replacement and generate
2401 any extra insns before OBJECT. If it zero, we do nothing if replacement
2404 Return 1 if we either had nothing to do or if we were able to do the
2405 needed replacement. Return 0 otherwise; we only return zero if
2406 EXTRA_INSNS is zero.
2408 We first try some simple transformations to avoid the creation of extra
2412 instantiate_virtual_regs_1 (loc, object, extra_insns)
2426 /* Re-start here to avoid recursion in common cases. */
2433 code = GET_CODE (x);
2435 /* Check for some special cases. */
2452 /* We are allowed to set the virtual registers. This means that
2453 that the actual register should receive the source minus the
2454 appropriate offset. This is used, for example, in the handling
2455 of non-local gotos. */
2456 if (SET_DEST (x) == virtual_incoming_args_rtx)
2457 new = arg_pointer_rtx, offset = - in_arg_offset;
2458 else if (SET_DEST (x) == virtual_stack_vars_rtx)
2459 new = frame_pointer_rtx, offset = - var_offset;
2460 else if (SET_DEST (x) == virtual_stack_dynamic_rtx)
2461 new = stack_pointer_rtx, offset = - dynamic_offset;
2462 else if (SET_DEST (x) == virtual_outgoing_args_rtx)
2463 new = stack_pointer_rtx, offset = - out_arg_offset;
2467 /* The only valid sources here are PLUS or REG. Just do
2468 the simplest possible thing to handle them. */
2469 if (GET_CODE (SET_SRC (x)) != REG
2470 && GET_CODE (SET_SRC (x)) != PLUS)
2474 if (GET_CODE (SET_SRC (x)) != REG)
2475 temp = force_operand (SET_SRC (x), NULL_RTX);
2478 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
2482 emit_insns_before (seq, object);
2485 if (!validate_change (object, &SET_SRC (x), temp, 0)
2492 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
2497 /* Handle special case of virtual register plus constant. */
2498 if (CONSTANT_P (XEXP (x, 1)))
2502 /* Check for (plus (plus VIRT foo) (const_int)) first. */
2503 if (GET_CODE (XEXP (x, 0)) == PLUS)
2505 rtx inner = XEXP (XEXP (x, 0), 0);
2507 if (inner == virtual_incoming_args_rtx)
2508 new = arg_pointer_rtx, offset = in_arg_offset;
2509 else if (inner == virtual_stack_vars_rtx)
2510 new = frame_pointer_rtx, offset = var_offset;
2511 else if (inner == virtual_stack_dynamic_rtx)
2512 new = stack_pointer_rtx, offset = dynamic_offset;
2513 else if (inner == virtual_outgoing_args_rtx)
2514 new = stack_pointer_rtx, offset = out_arg_offset;
2521 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
2523 new = gen_rtx (PLUS, Pmode, new, XEXP (XEXP (x, 0), 1));
2526 else if (XEXP (x, 0) == virtual_incoming_args_rtx)
2527 new = arg_pointer_rtx, offset = in_arg_offset;
2528 else if (XEXP (x, 0) == virtual_stack_vars_rtx)
2529 new = frame_pointer_rtx, offset = var_offset;
2530 else if (XEXP (x, 0) == virtual_stack_dynamic_rtx)
2531 new = stack_pointer_rtx, offset = dynamic_offset;
2532 else if (XEXP (x, 0) == virtual_outgoing_args_rtx)
2533 new = stack_pointer_rtx, offset = out_arg_offset;
2536 /* We know the second operand is a constant. Unless the
2537 first operand is a REG (which has been already checked),
2538 it needs to be checked. */
2539 if (GET_CODE (XEXP (x, 0)) != REG)
2549 new = plus_constant (XEXP (x, 1), offset);
2551 /* If the new constant is zero, try to replace the sum with its
2553 if (new == const0_rtx
2554 && validate_change (object, loc, XEXP (x, 0), 0))
2557 /* Next try to replace constant with new one. */
2558 if (!validate_change (object, &XEXP (x, 1), new, 0))
2566 /* Otherwise copy the new constant into a register and replace
2567 constant with that register. */
2568 temp = gen_reg_rtx (Pmode);
2569 if (validate_change (object, &XEXP (x, 1), temp, 0))
2570 emit_insn_before (gen_move_insn (temp, new), object);
2573 /* If that didn't work, replace this expression with a
2574 register containing the sum. */
2576 new = gen_rtx (PLUS, Pmode, XEXP (x, 0), new);
2580 temp = force_operand (new, NULL_RTX);
2584 emit_insns_before (seq, object);
2585 if (! validate_change (object, loc, temp, 0)
2586 && ! validate_replace_rtx (x, temp, object))
2594 /* Fall through to generic two-operand expression case. */
2600 case DIV: case UDIV:
2601 case MOD: case UMOD:
2602 case AND: case IOR: case XOR:
2603 case LSHIFT: case ASHIFT: case ROTATE:
2604 case ASHIFTRT: case LSHIFTRT: case ROTATERT:
2606 case GE: case GT: case GEU: case GTU:
2607 case LE: case LT: case LEU: case LTU:
2608 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
2609 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
2614 /* Most cases of MEM that convert to valid addresses have already been
2615 handled by our scan of regno_reg_rtx. The only special handling we
2616 need here is to make a copy of the rtx to ensure it isn't being
2617 shared if we have to change it to a pseudo.
2619 If the rtx is a simple reference to an address via a virtual register,
2620 it can potentially be shared. In such cases, first try to make it
2621 a valid address, which can also be shared. Otherwise, copy it and
2624 First check for common cases that need no processing. These are
2625 usually due to instantiation already being done on a previous instance
2629 if (CONSTANT_ADDRESS_P (temp)
2630 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
2631 || temp == arg_pointer_rtx
2633 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2634 || temp == hard_frame_pointer_rtx
2636 || temp == frame_pointer_rtx)
2639 if (GET_CODE (temp) == PLUS
2640 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
2641 && (XEXP (temp, 0) == frame_pointer_rtx
2642 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2643 || XEXP (temp, 0) == hard_frame_pointer_rtx
2645 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
2646 || XEXP (temp, 0) == arg_pointer_rtx
2651 if (temp == virtual_stack_vars_rtx
2652 || temp == virtual_incoming_args_rtx
2653 || (GET_CODE (temp) == PLUS
2654 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
2655 && (XEXP (temp, 0) == virtual_stack_vars_rtx
2656 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
2658 /* This MEM may be shared. If the substitution can be done without
2659 the need to generate new pseudos, we want to do it in place
2660 so all copies of the shared rtx benefit. The call below will
2661 only make substitutions if the resulting address is still
2664 Note that we cannot pass X as the object in the recursive call
2665 since the insn being processed may not allow all valid
2666 addresses. However, if we were not passed on object, we can
2667 only modify X without copying it if X will have a valid
2670 ??? Also note that this can still lose if OBJECT is an insn that
2671 has less restrictions on an address that some other insn.
2672 In that case, we will modify the shared address. This case
2673 doesn't seem very likely, though. */
2675 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
2676 object ? object : x, 0))
2679 /* Otherwise make a copy and process that copy. We copy the entire
2680 RTL expression since it might be a PLUS which could also be
2682 *loc = x = copy_rtx (x);
2685 /* Fall through to generic unary operation case. */
2689 case STRICT_LOW_PART:
2691 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
2692 case SIGN_EXTEND: case ZERO_EXTEND:
2693 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
2694 case FLOAT: case FIX:
2695 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
2699 /* These case either have just one operand or we know that we need not
2700 check the rest of the operands. */
2705 /* Try to replace with a PLUS. If that doesn't work, compute the sum
2706 in front of this insn and substitute the temporary. */
2707 if (x == virtual_incoming_args_rtx)
2708 new = arg_pointer_rtx, offset = in_arg_offset;
2709 else if (x == virtual_stack_vars_rtx)
2710 new = frame_pointer_rtx, offset = var_offset;
2711 else if (x == virtual_stack_dynamic_rtx)
2712 new = stack_pointer_rtx, offset = dynamic_offset;
2713 else if (x == virtual_outgoing_args_rtx)
2714 new = stack_pointer_rtx, offset = out_arg_offset;
2718 temp = plus_constant (new, offset);
2719 if (!validate_change (object, loc, temp, 0))
2725 temp = force_operand (temp, NULL_RTX);
2729 emit_insns_before (seq, object);
2730 if (! validate_change (object, loc, temp, 0)
2731 && ! validate_replace_rtx (x, temp, object))
2739 /* Scan all subexpressions. */
2740 fmt = GET_RTX_FORMAT (code);
2741 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
2744 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
2747 else if (*fmt == 'E')
2748 for (j = 0; j < XVECLEN (x, i); j++)
2749 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
2756 /* Optimization: assuming this function does not receive nonlocal gotos,
2757 delete the handlers for such, as well as the insns to establish
2758 and disestablish them. */
2764 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
2766 /* Delete the handler by turning off the flag that would
2767 prevent jump_optimize from deleting it.
2768 Also permit deletion of the nonlocal labels themselves
2769 if nothing local refers to them. */
2770 if (GET_CODE (insn) == CODE_LABEL)
2771 LABEL_PRESERVE_P (insn) = 0;
2772 if (GET_CODE (insn) == INSN
2773 && ((nonlocal_goto_handler_slot != 0
2774 && reg_mentioned_p (nonlocal_goto_handler_slot, PATTERN (insn)))
2775 || (nonlocal_goto_stack_level != 0
2776 && reg_mentioned_p (nonlocal_goto_stack_level,
2782 /* Return a list (chain of EXPR_LIST nodes) for the nonlocal labels
2783 of the current function. */
2786 nonlocal_label_rtx_list ()
2791 for (t = nonlocal_labels; t; t = TREE_CHAIN (t))
2792 x = gen_rtx (EXPR_LIST, VOIDmode, label_rtx (TREE_VALUE (t)), x);
2797 /* Output a USE for any register use in RTL.
2798 This is used with -noreg to mark the extent of lifespan
2799 of any registers used in a user-visible variable's DECL_RTL. */
2805 if (GET_CODE (rtl) == REG)
2806 /* This is a register variable. */
2807 emit_insn (gen_rtx (USE, VOIDmode, rtl));
2808 else if (GET_CODE (rtl) == MEM
2809 && GET_CODE (XEXP (rtl, 0)) == REG
2810 && (REGNO (XEXP (rtl, 0)) < FIRST_VIRTUAL_REGISTER
2811 || REGNO (XEXP (rtl, 0)) > LAST_VIRTUAL_REGISTER)
2812 && XEXP (rtl, 0) != current_function_internal_arg_pointer)
2813 /* This is a variable-sized structure. */
2814 emit_insn (gen_rtx (USE, VOIDmode, XEXP (rtl, 0)));
2817 /* Like use_variable except that it outputs the USEs after INSN
2818 instead of at the end of the insn-chain. */
2821 use_variable_after (rtl, insn)
2824 if (GET_CODE (rtl) == REG)
2825 /* This is a register variable. */
2826 emit_insn_after (gen_rtx (USE, VOIDmode, rtl), insn);
2827 else if (GET_CODE (rtl) == MEM
2828 && GET_CODE (XEXP (rtl, 0)) == REG
2829 && (REGNO (XEXP (rtl, 0)) < FIRST_VIRTUAL_REGISTER
2830 || REGNO (XEXP (rtl, 0)) > LAST_VIRTUAL_REGISTER)
2831 && XEXP (rtl, 0) != current_function_internal_arg_pointer)
2832 /* This is a variable-sized structure. */
2833 emit_insn_after (gen_rtx (USE, VOIDmode, XEXP (rtl, 0)), insn);
2839 return max_parm_reg;
2842 /* Return the first insn following those generated by `assign_parms'. */
2845 get_first_nonparm_insn ()
2848 return NEXT_INSN (last_parm_insn);
2849 return get_insns ();
2852 /* Return the first NOTE_INSN_BLOCK_BEG note in the function.
2853 Crash if there is none. */
2856 get_first_block_beg ()
2858 register rtx searcher;
2859 register rtx insn = get_first_nonparm_insn ();
2861 for (searcher = insn; searcher; searcher = NEXT_INSN (searcher))
2862 if (GET_CODE (searcher) == NOTE
2863 && NOTE_LINE_NUMBER (searcher) == NOTE_INSN_BLOCK_BEG)
2866 abort (); /* Invalid call to this function. (See comments above.) */
2870 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
2871 This means a type for which function calls must pass an address to the
2872 function or get an address back from the function.
2873 EXP may be a type node or an expression (whose type is tested). */
2876 aggregate_value_p (exp)
2879 int i, regno, nregs;
2882 if (TREE_CODE_CLASS (TREE_CODE (exp)) == 't')
2885 type = TREE_TYPE (exp);
2887 if (RETURN_IN_MEMORY (type))
2889 if (flag_pcc_struct_return
2890 && (TREE_CODE (type) == RECORD_TYPE
2891 || TREE_CODE (type) == UNION_TYPE
2892 || TREE_CODE (type) == QUAL_UNION_TYPE
2893 || TREE_CODE (type) == ARRAY_TYPE))
2895 /* Make sure we have suitable call-clobbered regs to return
2896 the value in; if not, we must return it in memory. */
2897 reg = hard_function_value (type, 0);
2898 regno = REGNO (reg);
2899 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
2900 for (i = 0; i < nregs; i++)
2901 if (! call_used_regs[regno + i])
2906 /* Assign RTL expressions to the function's parameters.
2907 This may involve copying them into registers and using
2908 those registers as the RTL for them.
2910 If SECOND_TIME is non-zero it means that this function is being
2911 called a second time. This is done by integrate.c when a function's
2912 compilation is deferred. We need to come back here in case the
2913 FUNCTION_ARG macro computes items needed for the rest of the compilation
2914 (such as changing which registers are fixed or caller-saved). But suppress
2915 writing any insns or setting DECL_RTL of anything in this case. */
2918 assign_parms (fndecl, second_time)
2923 register rtx entry_parm = 0;
2924 register rtx stack_parm = 0;
2925 CUMULATIVE_ARGS args_so_far;
2926 enum machine_mode promoted_mode, passed_mode, nominal_mode;
2928 /* Total space needed so far for args on the stack,
2929 given as a constant and a tree-expression. */
2930 struct args_size stack_args_size;
2931 tree fntype = TREE_TYPE (fndecl);
2932 tree fnargs = DECL_ARGUMENTS (fndecl);
2933 /* This is used for the arg pointer when referring to stack args. */
2934 rtx internal_arg_pointer;
2935 /* This is a dummy PARM_DECL that we used for the function result if
2936 the function returns a structure. */
2937 tree function_result_decl = 0;
2938 int nparmregs = list_length (fnargs) + LAST_VIRTUAL_REGISTER + 1;
2939 int varargs_setup = 0;
2940 rtx conversion_insns = 0;
2941 /* FUNCTION_ARG may look at this variable. Since this is not
2942 expanding a call it will always be zero in this function. */
2943 int current_call_is_indirect = 0;
2945 /* Nonzero if the last arg is named `__builtin_va_alist',
2946 which is used on some machines for old-fashioned non-ANSI varargs.h;
2947 this should be stuck onto the stack as if it had arrived there. */
2950 && (parm = tree_last (fnargs)) != 0
2952 && (! strcmp (IDENTIFIER_POINTER (DECL_NAME (parm)),
2953 "__builtin_va_alist")));
2955 /* Nonzero if function takes extra anonymous args.
2956 This means the last named arg must be on the stack
2957 right before the anonymous ones. */
2959 = (TYPE_ARG_TYPES (fntype) != 0
2960 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
2961 != void_type_node));
2963 /* If the reg that the virtual arg pointer will be translated into is
2964 not a fixed reg or is the stack pointer, make a copy of the virtual
2965 arg pointer, and address parms via the copy. The frame pointer is
2966 considered fixed even though it is not marked as such.
2968 The second time through, simply use ap to avoid generating rtx. */
2970 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
2971 || ! (fixed_regs[ARG_POINTER_REGNUM]
2972 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM))
2974 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
2976 internal_arg_pointer = virtual_incoming_args_rtx;
2977 current_function_internal_arg_pointer = internal_arg_pointer;
2979 stack_args_size.constant = 0;
2980 stack_args_size.var = 0;
2982 /* If struct value address is treated as the first argument, make it so. */
2983 if (aggregate_value_p (DECL_RESULT (fndecl))
2984 && ! current_function_returns_pcc_struct
2985 && struct_value_incoming_rtx == 0)
2987 tree type = build_pointer_type (fntype);
2989 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
2991 DECL_ARG_TYPE (function_result_decl) = type;
2992 TREE_CHAIN (function_result_decl) = fnargs;
2993 fnargs = function_result_decl;
2996 parm_reg_stack_loc = (rtx *) oballoc (nparmregs * sizeof (rtx));
2997 bzero (parm_reg_stack_loc, nparmregs * sizeof (rtx));
2999 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
3000 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
3002 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX);
3005 /* We haven't yet found an argument that we must push and pretend the
3007 current_function_pretend_args_size = 0;
3009 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
3012 = (TREE_CODE (TREE_TYPE (parm)) == ARRAY_TYPE
3013 || TREE_CODE (TREE_TYPE (parm)) == RECORD_TYPE
3014 || TREE_CODE (TREE_TYPE (parm)) == UNION_TYPE
3015 || TREE_CODE (TREE_TYPE (parm)) == QUAL_UNION_TYPE);
3016 struct args_size stack_offset;
3017 struct args_size arg_size;
3018 int passed_pointer = 0;
3019 tree passed_type = DECL_ARG_TYPE (parm);
3021 /* Set LAST_NAMED if this is last named arg before some
3022 anonymous args. We treat it as if it were anonymous too. */
3023 int last_named = ((TREE_CHAIN (parm) == 0
3024 || DECL_NAME (TREE_CHAIN (parm)) == 0)
3025 && (vararg || stdarg));
3027 if (TREE_TYPE (parm) == error_mark_node
3028 /* This can happen after weird syntax errors
3029 or if an enum type is defined among the parms. */
3030 || TREE_CODE (parm) != PARM_DECL
3031 || passed_type == NULL)
3033 DECL_INCOMING_RTL (parm) = DECL_RTL (parm) = gen_rtx (MEM, BLKmode,
3035 TREE_USED (parm) = 1;
3039 /* For varargs.h function, save info about regs and stack space
3040 used by the individual args, not including the va_alist arg. */
3041 if (vararg && last_named)
3042 current_function_args_info = args_so_far;
3044 /* Find mode of arg as it is passed, and mode of arg
3045 as it should be during execution of this function. */
3046 passed_mode = TYPE_MODE (passed_type);
3047 nominal_mode = TYPE_MODE (TREE_TYPE (parm));
3049 /* If the parm's mode is VOID, its value doesn't matter,
3050 and avoid the usual things like emit_move_insn that could crash. */
3051 if (nominal_mode == VOIDmode)
3053 DECL_INCOMING_RTL (parm) = DECL_RTL (parm) = const0_rtx;
3057 /* See if this arg was passed by invisible reference. It is if
3058 it is an object whose size depends on the contents of the
3059 object itself or if the machine requires these objects be passed
3062 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
3063 && contains_placeholder_p (TYPE_SIZE (passed_type)))
3064 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3065 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
3066 passed_type, ! last_named)
3070 passed_type = build_pointer_type (passed_type);
3072 passed_mode = nominal_mode = Pmode;
3075 promoted_mode = passed_mode;
3077 #ifdef PROMOTE_FUNCTION_ARGS
3078 /* Compute the mode in which the arg is actually extended to. */
3079 if (TREE_CODE (passed_type) == INTEGER_TYPE
3080 || TREE_CODE (passed_type) == ENUMERAL_TYPE
3081 || TREE_CODE (passed_type) == BOOLEAN_TYPE
3082 || TREE_CODE (passed_type) == CHAR_TYPE
3083 || TREE_CODE (passed_type) == REAL_TYPE
3084 || TREE_CODE (passed_type) == POINTER_TYPE
3085 || TREE_CODE (passed_type) == OFFSET_TYPE)
3087 unsignedp = TREE_UNSIGNED (passed_type);
3088 PROMOTE_MODE (promoted_mode, unsignedp, passed_type);
3092 /* Let machine desc say which reg (if any) the parm arrives in.
3093 0 means it arrives on the stack. */
3094 #ifdef FUNCTION_INCOMING_ARG
3095 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
3096 passed_type, ! last_named);
3098 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
3099 passed_type, ! last_named);
3103 passed_mode = promoted_mode;
3105 #ifdef SETUP_INCOMING_VARARGS
3106 /* If this is the last named parameter, do any required setup for
3107 varargs or stdargs. We need to know about the case of this being an
3108 addressable type, in which case we skip the registers it
3109 would have arrived in.
3111 For stdargs, LAST_NAMED will be set for two parameters, the one that
3112 is actually the last named, and the dummy parameter. We only
3113 want to do this action once.
3115 Also, indicate when RTL generation is to be suppressed. */
3116 if (last_named && !varargs_setup)
3118 SETUP_INCOMING_VARARGS (args_so_far, passed_mode, passed_type,
3119 current_function_pretend_args_size,
3125 /* Determine parm's home in the stack,
3126 in case it arrives in the stack or we should pretend it did.
3128 Compute the stack position and rtx where the argument arrives
3131 There is one complexity here: If this was a parameter that would
3132 have been passed in registers, but wasn't only because it is
3133 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
3134 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
3135 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
3136 0 as it was the previous time. */
3138 locate_and_pad_parm (passed_mode, passed_type,
3139 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3142 #ifdef FUNCTION_INCOMING_ARG
3143 FUNCTION_INCOMING_ARG (args_so_far, passed_mode,
3146 || varargs_setup)) != 0,
3148 FUNCTION_ARG (args_so_far, passed_mode,
3150 ! last_named || varargs_setup) != 0,
3153 fndecl, &stack_args_size, &stack_offset, &arg_size);
3157 rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
3159 if (offset_rtx == const0_rtx)
3160 stack_parm = gen_rtx (MEM, passed_mode, internal_arg_pointer);
3162 stack_parm = gen_rtx (MEM, passed_mode,
3163 gen_rtx (PLUS, Pmode,
3164 internal_arg_pointer, offset_rtx));
3166 /* If this is a memory ref that contains aggregate components,
3167 mark it as such for cse and loop optimize. */
3168 MEM_IN_STRUCT_P (stack_parm) = aggregate;
3171 /* If this parameter was passed both in registers and in the stack,
3172 use the copy on the stack. */
3173 if (MUST_PASS_IN_STACK (passed_mode, passed_type))
3176 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3177 /* If this parm was passed part in regs and part in memory,
3178 pretend it arrived entirely in memory
3179 by pushing the register-part onto the stack.
3181 In the special case of a DImode or DFmode that is split,
3182 we could put it together in a pseudoreg directly,
3183 but for now that's not worth bothering with. */
3187 int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, passed_mode,
3188 passed_type, ! last_named);
3192 current_function_pretend_args_size
3193 = (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
3194 / (PARM_BOUNDARY / BITS_PER_UNIT)
3195 * (PARM_BOUNDARY / BITS_PER_UNIT));
3198 move_block_from_reg (REGNO (entry_parm),
3199 validize_mem (stack_parm), nregs,
3200 int_size_in_bytes (TREE_TYPE (parm)));
3201 entry_parm = stack_parm;
3206 /* If we didn't decide this parm came in a register,
3207 by default it came on the stack. */
3208 if (entry_parm == 0)
3209 entry_parm = stack_parm;
3211 /* Record permanently how this parm was passed. */
3213 DECL_INCOMING_RTL (parm) = entry_parm;
3215 /* If there is actually space on the stack for this parm,
3216 count it in stack_args_size; otherwise set stack_parm to 0
3217 to indicate there is no preallocated stack slot for the parm. */
3219 if (entry_parm == stack_parm
3220 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
3221 /* On some machines, even if a parm value arrives in a register
3222 there is still an (uninitialized) stack slot allocated for it.
3224 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
3225 whether this parameter already has a stack slot allocated,
3226 because an arg block exists only if current_function_args_size
3227 is larger than some threshhold, and we haven't calculated that
3228 yet. So, for now, we just assume that stack slots never exist
3230 || REG_PARM_STACK_SPACE (fndecl) > 0
3234 stack_args_size.constant += arg_size.constant;
3236 ADD_PARM_SIZE (stack_args_size, arg_size.var);
3239 /* No stack slot was pushed for this parm. */
3242 /* Update info on where next arg arrives in registers. */
3244 FUNCTION_ARG_ADVANCE (args_so_far, passed_mode,
3245 passed_type, ! last_named);
3247 /* If this is our second time through, we are done with this parm. */
3251 /* If we can't trust the parm stack slot to be aligned enough
3252 for its ultimate type, don't use that slot after entry.
3253 We'll make another stack slot, if we need one. */
3255 int thisparm_boundary
3256 = FUNCTION_ARG_BOUNDARY (passed_mode, passed_type);
3258 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
3262 /* If parm was passed in memory, and we need to convert it on entry,
3263 don't store it back in that same slot. */
3265 && nominal_mode != BLKmode && nominal_mode != passed_mode)
3269 /* Now adjust STACK_PARM to the mode and precise location
3270 where this parameter should live during execution,
3271 if we discover that it must live in the stack during execution.
3272 To make debuggers happier on big-endian machines, we store
3273 the value in the last bytes of the space available. */
3275 if (nominal_mode != BLKmode && nominal_mode != passed_mode
3280 #if BYTES_BIG_ENDIAN
3281 if (GET_MODE_SIZE (nominal_mode) < UNITS_PER_WORD)
3282 stack_offset.constant += (GET_MODE_SIZE (passed_mode)
3283 - GET_MODE_SIZE (nominal_mode));
3286 offset_rtx = ARGS_SIZE_RTX (stack_offset);
3287 if (offset_rtx == const0_rtx)
3288 stack_parm = gen_rtx (MEM, nominal_mode, internal_arg_pointer);
3290 stack_parm = gen_rtx (MEM, nominal_mode,
3291 gen_rtx (PLUS, Pmode,
3292 internal_arg_pointer, offset_rtx));
3294 /* If this is a memory ref that contains aggregate components,
3295 mark it as such for cse and loop optimize. */
3296 MEM_IN_STRUCT_P (stack_parm) = aggregate;
3300 /* ENTRY_PARM is an RTX for the parameter as it arrives,
3301 in the mode in which it arrives.
3302 STACK_PARM is an RTX for a stack slot where the parameter can live
3303 during the function (in case we want to put it there).
3304 STACK_PARM is 0 if no stack slot was pushed for it.
3306 Now output code if necessary to convert ENTRY_PARM to
3307 the type in which this function declares it,
3308 and store that result in an appropriate place,
3309 which may be a pseudo reg, may be STACK_PARM,
3310 or may be a local stack slot if STACK_PARM is 0.
3312 Set DECL_RTL to that place. */
3314 if (nominal_mode == BLKmode)
3316 /* If a BLKmode arrives in registers, copy it to a stack slot. */
3317 if (GET_CODE (entry_parm) == REG)
3319 int size_stored = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
3322 /* Note that we will be storing an integral number of words.
3323 So we have to be careful to ensure that we allocate an
3324 integral number of words. We do this below in the
3325 assign_stack_local if space was not allocated in the argument
3326 list. If it was, this will not work if PARM_BOUNDARY is not
3327 a multiple of BITS_PER_WORD. It isn't clear how to fix this
3328 if it becomes a problem. */
3330 if (stack_parm == 0)
3333 = assign_stack_local (GET_MODE (entry_parm), size_stored, 0);
3334 /* If this is a memory ref that contains aggregate components,
3335 mark it as such for cse and loop optimize. */
3336 MEM_IN_STRUCT_P (stack_parm) = aggregate;
3339 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
3342 move_block_from_reg (REGNO (entry_parm),
3343 validize_mem (stack_parm),
3344 size_stored / UNITS_PER_WORD,
3345 int_size_in_bytes (TREE_TYPE (parm)));
3347 DECL_RTL (parm) = stack_parm;
3349 else if (! ((obey_regdecls && ! DECL_REGISTER (parm)
3350 && ! DECL_INLINE (fndecl))
3351 /* layout_decl may set this. */
3352 || TREE_ADDRESSABLE (parm)
3353 || TREE_SIDE_EFFECTS (parm)
3354 /* If -ffloat-store specified, don't put explicit
3355 float variables into registers. */
3356 || (flag_float_store
3357 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
3358 /* Always assign pseudo to structure return or item passed
3359 by invisible reference. */
3360 || passed_pointer || parm == function_result_decl)
3362 /* Store the parm in a pseudoregister during the function, but we
3363 may need to do it in a wider mode. */
3365 register rtx parmreg;
3368 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
3369 if (TREE_CODE (TREE_TYPE (parm)) == INTEGER_TYPE
3370 || TREE_CODE (TREE_TYPE (parm)) == ENUMERAL_TYPE
3371 || TREE_CODE (TREE_TYPE (parm)) == BOOLEAN_TYPE
3372 || TREE_CODE (TREE_TYPE (parm)) == CHAR_TYPE
3373 || TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE
3374 || TREE_CODE (TREE_TYPE (parm)) == POINTER_TYPE
3375 || TREE_CODE (TREE_TYPE (parm)) == OFFSET_TYPE)
3377 PROMOTE_MODE (nominal_mode, unsignedp, TREE_TYPE (parm));
3380 parmreg = gen_reg_rtx (nominal_mode);
3381 REG_USERVAR_P (parmreg) = 1;
3383 /* If this was an item that we received a pointer to, set DECL_RTL
3387 DECL_RTL (parm) = gen_rtx (MEM, TYPE_MODE (TREE_TYPE (passed_type)), parmreg);
3388 MEM_IN_STRUCT_P (DECL_RTL (parm)) = aggregate;
3391 DECL_RTL (parm) = parmreg;
3393 /* Copy the value into the register. */
3394 if (GET_MODE (parmreg) != GET_MODE (entry_parm))
3396 /* If ENTRY_PARM is a hard register, it might be in a register
3397 not valid for operating in its mode (e.g., an odd-numbered
3398 register for a DFmode). In that case, moves are the only
3399 thing valid, so we can't do a convert from there. This
3400 occurs when the calling sequence allow such misaligned
3403 In addition, the conversion may involve a call, which could
3404 clobber parameters which haven't been copied to pseudo
3405 registers yet. Therefore, we must first copy the parm to
3406 a pseudo reg here, and save the conversion until after all
3407 parameters have been moved. */
3409 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
3411 emit_move_insn (tempreg, validize_mem (entry_parm));
3413 push_to_sequence (conversion_insns);
3414 convert_move (parmreg, tempreg, unsignedp);
3415 conversion_insns = get_insns ();
3419 emit_move_insn (parmreg, validize_mem (entry_parm));
3421 /* If we were passed a pointer but the actual value
3422 can safely live in a register, put it in one. */
3423 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
3424 && ! ((obey_regdecls && ! DECL_REGISTER (parm)
3425 && ! DECL_INLINE (fndecl))
3426 /* layout_decl may set this. */
3427 || TREE_ADDRESSABLE (parm)
3428 || TREE_SIDE_EFFECTS (parm)
3429 /* If -ffloat-store specified, don't put explicit
3430 float variables into registers. */
3431 || (flag_float_store
3432 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE)))
3434 /* We can't use nominal_mode, because it will have been set to
3435 Pmode above. We must use the actual mode of the parm. */
3436 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
3437 emit_move_insn (parmreg, DECL_RTL (parm));
3438 DECL_RTL (parm) = parmreg;
3439 /* STACK_PARM is the pointer, not the parm, and PARMREG is
3443 #ifdef FUNCTION_ARG_CALLEE_COPIES
3444 /* If we are passed an arg by reference and it is our responsibility
3445 to make a copy, do it now.
3446 PASSED_TYPE and PASSED mode now refer to the pointer, not the
3447 original argument, so we must recreate them in the call to
3448 FUNCTION_ARG_CALLEE_COPIES. */
3449 /* ??? Later add code to handle the case that if the argument isn't
3450 modified, don't do the copy. */
3452 else if (passed_pointer
3453 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
3454 TYPE_MODE (DECL_ARG_TYPE (parm)),
3455 DECL_ARG_TYPE (parm),
3459 tree type = DECL_ARG_TYPE (parm);
3461 /* This sequence may involve a library call perhaps clobbering
3462 registers that haven't been copied to pseudos yet. */
3464 push_to_sequence (conversion_insns);
3466 if (TYPE_SIZE (type) == 0
3467 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
3469 /* This is a variable sized object. */
3470 /* ??? Can we use expr_size here? */
3471 rtx size_rtx = expand_expr (size_in_bytes (type), NULL_RTX,
3472 TYPE_MODE (sizetype), 0);
3474 copy = gen_rtx (MEM, BLKmode,
3475 allocate_dynamic_stack_space (size_rtx, NULL_RTX,
3476 TYPE_ALIGN (type)));
3480 int size = int_size_in_bytes (type);
3481 copy = assign_stack_temp (TYPE_MODE (type), size, 1);
3484 store_expr (parm, copy, 0);
3485 emit_move_insn (parmreg, XEXP (copy, 0));
3486 conversion_insns = get_insns ();
3489 #endif /* FUNCTION_ARG_CALLEE_COPIES */
3491 /* In any case, record the parm's desired stack location
3492 in case we later discover it must live in the stack.
3494 If it is a COMPLEX value, store the stack location for both
3497 if (GET_CODE (parmreg) == CONCAT)
3498 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
3500 regno = REGNO (parmreg);
3502 if (regno >= nparmregs)
3505 int old_nparmregs = nparmregs;
3507 nparmregs = regno + 5;
3508 new = (rtx *) oballoc (nparmregs * sizeof (rtx));
3509 bcopy (parm_reg_stack_loc, new, old_nparmregs * sizeof (rtx));
3510 bzero (new + old_nparmregs,
3511 (nparmregs - old_nparmregs) * sizeof (rtx));
3512 parm_reg_stack_loc = new;
3515 if (GET_CODE (parmreg) == CONCAT)
3517 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
3519 if (stack_parm != 0)
3521 parm_reg_stack_loc[REGNO (gen_lowpart (submode, parmreg))]
3522 = gen_lowpart (submode, stack_parm);
3523 parm_reg_stack_loc[REGNO (gen_highpart (submode, parmreg))]
3524 = gen_highpart (submode, stack_parm);
3528 parm_reg_stack_loc[REGNO (gen_lowpart (submode, parmreg))]
3530 parm_reg_stack_loc[REGNO (gen_highpart (submode, parmreg))]
3535 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
3537 /* Mark the register as eliminable if we did no conversion
3538 and it was copied from memory at a fixed offset,
3539 and the arg pointer was not copied to a pseudo-reg.
3540 If the arg pointer is a pseudo reg or the offset formed
3541 an invalid address, such memory-equivalences
3542 as we make here would screw up life analysis for it. */
3543 if (nominal_mode == passed_mode
3544 && GET_CODE (entry_parm) == MEM
3545 && entry_parm == stack_parm
3546 && stack_offset.var == 0
3547 && reg_mentioned_p (virtual_incoming_args_rtx,
3548 XEXP (entry_parm, 0)))
3549 REG_NOTES (get_last_insn ())
3550 = gen_rtx (EXPR_LIST, REG_EQUIV,
3551 entry_parm, REG_NOTES (get_last_insn ()));
3553 /* For pointer data type, suggest pointer register. */
3554 if (TREE_CODE (TREE_TYPE (parm)) == POINTER_TYPE)
3555 mark_reg_pointer (parmreg);
3559 /* Value must be stored in the stack slot STACK_PARM
3560 during function execution. */
3562 if (passed_mode != nominal_mode)
3564 /* Conversion is required. */
3565 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
3567 emit_move_insn (tempreg, validize_mem (entry_parm));
3569 push_to_sequence (conversion_insns);
3570 entry_parm = convert_to_mode (nominal_mode, tempreg,
3571 TREE_UNSIGNED (TREE_TYPE (parm)));
3572 conversion_insns = get_insns ();
3576 if (entry_parm != stack_parm)
3578 if (stack_parm == 0)
3581 = assign_stack_local (GET_MODE (entry_parm),
3582 GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
3583 /* If this is a memory ref that contains aggregate components,
3584 mark it as such for cse and loop optimize. */
3585 MEM_IN_STRUCT_P (stack_parm) = aggregate;
3588 if (passed_mode != nominal_mode)
3590 push_to_sequence (conversion_insns);
3591 emit_move_insn (validize_mem (stack_parm),
3592 validize_mem (entry_parm));
3593 conversion_insns = get_insns ();
3597 emit_move_insn (validize_mem (stack_parm),
3598 validize_mem (entry_parm));
3601 DECL_RTL (parm) = stack_parm;
3604 /* If this "parameter" was the place where we are receiving the
3605 function's incoming structure pointer, set up the result. */
3606 if (parm == function_result_decl)
3607 DECL_RTL (DECL_RESULT (fndecl))
3608 = gen_rtx (MEM, DECL_MODE (DECL_RESULT (fndecl)), DECL_RTL (parm));
3610 if (TREE_THIS_VOLATILE (parm))
3611 MEM_VOLATILE_P (DECL_RTL (parm)) = 1;
3612 if (TREE_READONLY (parm))
3613 RTX_UNCHANGING_P (DECL_RTL (parm)) = 1;
3616 /* Output all parameter conversion instructions (possibly including calls)
3617 now that all parameters have been copied out of hard registers. */
3618 emit_insns (conversion_insns);
3620 max_parm_reg = max_reg_num ();
3621 last_parm_insn = get_last_insn ();
3623 current_function_args_size = stack_args_size.constant;
3625 /* Adjust function incoming argument size for alignment and
3628 #ifdef REG_PARM_STACK_SPACE
3629 #ifndef MAYBE_REG_PARM_STACK_SPACE
3630 current_function_args_size = MAX (current_function_args_size,
3631 REG_PARM_STACK_SPACE (fndecl));
3635 #ifdef STACK_BOUNDARY
3636 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
3638 current_function_args_size
3639 = ((current_function_args_size + STACK_BYTES - 1)
3640 / STACK_BYTES) * STACK_BYTES;
3643 #ifdef ARGS_GROW_DOWNWARD
3644 current_function_arg_offset_rtx
3645 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
3646 : expand_expr (size_binop (MINUS_EXPR, stack_args_size.var,
3647 size_int (-stack_args_size.constant)),
3648 NULL_RTX, VOIDmode, 0));
3650 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
3653 /* See how many bytes, if any, of its args a function should try to pop
3656 current_function_pops_args = RETURN_POPS_ARGS (TREE_TYPE (fndecl),
3657 current_function_args_size);
3659 /* For stdarg.h function, save info about regs and stack space
3660 used by the named args. */
3663 current_function_args_info = args_so_far;
3665 /* Set the rtx used for the function return value. Put this in its
3666 own variable so any optimizers that need this information don't have
3667 to include tree.h. Do this here so it gets done when an inlined
3668 function gets output. */
3670 current_function_return_rtx = DECL_RTL (DECL_RESULT (fndecl));
3673 /* Indicate whether REGNO is an incoming argument to the current function
3674 that was promoted to a wider mode. If so, return the RTX for the
3675 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
3676 that REGNO is promoted from and whether the promotion was signed or
3679 #ifdef PROMOTE_FUNCTION_ARGS
3682 promoted_input_arg (regno, pmode, punsignedp)
3684 enum machine_mode *pmode;
3689 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
3690 arg = TREE_CHAIN (arg))
3691 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
3692 && REGNO (DECL_INCOMING_RTL (arg)) == regno
3693 && (TREE_CODE (TREE_TYPE (arg)) == INTEGER_TYPE
3694 || TREE_CODE (TREE_TYPE (arg)) == ENUMERAL_TYPE
3695 || TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE
3696 || TREE_CODE (TREE_TYPE (arg)) == CHAR_TYPE
3697 || TREE_CODE (TREE_TYPE (arg)) == REAL_TYPE
3698 || TREE_CODE (TREE_TYPE (arg)) == POINTER_TYPE
3699 || TREE_CODE (TREE_TYPE (arg)) == OFFSET_TYPE))
3701 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
3702 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
3704 PROMOTE_MODE (mode, unsignedp, TREE_TYPE (arg));
3705 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
3706 && mode != DECL_MODE (arg))
3708 *pmode = DECL_MODE (arg);
3709 *punsignedp = unsignedp;
3710 return DECL_INCOMING_RTL (arg);
3719 /* Compute the size and offset from the start of the stacked arguments for a
3720 parm passed in mode PASSED_MODE and with type TYPE.
3722 INITIAL_OFFSET_PTR points to the current offset into the stacked
3725 The starting offset and size for this parm are returned in *OFFSET_PTR
3726 and *ARG_SIZE_PTR, respectively.
3728 IN_REGS is non-zero if the argument will be passed in registers. It will
3729 never be set if REG_PARM_STACK_SPACE is not defined.
3731 FNDECL is the function in which the argument was defined.
3733 There are two types of rounding that are done. The first, controlled by
3734 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
3735 list to be aligned to the specific boundary (in bits). This rounding
3736 affects the initial and starting offsets, but not the argument size.
3738 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3739 optionally rounds the size of the parm to PARM_BOUNDARY. The
3740 initial offset is not affected by this rounding, while the size always
3741 is and the starting offset may be. */
3743 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
3744 initial_offset_ptr is positive because locate_and_pad_parm's
3745 callers pass in the total size of args so far as
3746 initial_offset_ptr. arg_size_ptr is always positive.*/
3748 static void pad_to_arg_alignment (), pad_below ();
3751 locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
3752 initial_offset_ptr, offset_ptr, arg_size_ptr)
3753 enum machine_mode passed_mode;
3757 struct args_size *initial_offset_ptr;
3758 struct args_size *offset_ptr;
3759 struct args_size *arg_size_ptr;
3762 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
3763 enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
3764 int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
3765 int boundary_in_bytes = boundary / BITS_PER_UNIT;
3766 int reg_parm_stack_space = 0;
3768 #ifdef REG_PARM_STACK_SPACE
3769 /* If we have found a stack parm before we reach the end of the
3770 area reserved for registers, skip that area. */
3773 #ifdef MAYBE_REG_PARM_STACK_SPACE
3774 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
3776 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
3778 if (reg_parm_stack_space > 0)
3780 if (initial_offset_ptr->var)
3782 initial_offset_ptr->var
3783 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
3784 size_int (reg_parm_stack_space));
3785 initial_offset_ptr->constant = 0;
3787 else if (initial_offset_ptr->constant < reg_parm_stack_space)
3788 initial_offset_ptr->constant = reg_parm_stack_space;
3791 #endif /* REG_PARM_STACK_SPACE */
3793 arg_size_ptr->var = 0;
3794 arg_size_ptr->constant = 0;
3796 #ifdef ARGS_GROW_DOWNWARD
3797 if (initial_offset_ptr->var)
3799 offset_ptr->constant = 0;
3800 offset_ptr->var = size_binop (MINUS_EXPR, integer_zero_node,
3801 initial_offset_ptr->var);
3805 offset_ptr->constant = - initial_offset_ptr->constant;
3806 offset_ptr->var = 0;
3808 if (where_pad == upward
3809 && (TREE_CODE (sizetree) != INTEGER_CST
3810 || ((TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)))
3811 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
3812 SUB_PARM_SIZE (*offset_ptr, sizetree);
3813 if (where_pad != downward)
3814 pad_to_arg_alignment (offset_ptr, boundary);
3815 if (initial_offset_ptr->var)
3817 arg_size_ptr->var = size_binop (MINUS_EXPR,
3818 size_binop (MINUS_EXPR,
3820 initial_offset_ptr->var),
3825 arg_size_ptr->constant = (- initial_offset_ptr->constant -
3826 offset_ptr->constant);
3828 /* ADD_PARM_SIZE (*arg_size_ptr, sizetree); */
3829 if (where_pad == downward)
3830 pad_below (arg_size_ptr, passed_mode, sizetree);
3831 #else /* !ARGS_GROW_DOWNWARD */
3832 pad_to_arg_alignment (initial_offset_ptr, boundary);
3833 *offset_ptr = *initial_offset_ptr;
3835 #ifdef PUSH_ROUNDING
3836 if (passed_mode != BLKmode)
3837 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
3840 if (where_pad != none
3841 && (TREE_CODE (sizetree) != INTEGER_CST
3842 || ((TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)))
3843 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
3845 /* This must be done after rounding sizetree, so that it will subtract
3846 the same value that we explicitly add below. */
3847 if (where_pad == downward)
3848 pad_below (offset_ptr, passed_mode, sizetree);
3849 ADD_PARM_SIZE (*arg_size_ptr, sizetree);
3850 #endif /* ARGS_GROW_DOWNWARD */
3853 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
3854 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
3857 pad_to_arg_alignment (offset_ptr, boundary)
3858 struct args_size *offset_ptr;
3861 int boundary_in_bytes = boundary / BITS_PER_UNIT;
3863 if (boundary > BITS_PER_UNIT)
3865 if (offset_ptr->var)
3868 #ifdef ARGS_GROW_DOWNWARD
3873 (ARGS_SIZE_TREE (*offset_ptr),
3874 boundary / BITS_PER_UNIT);
3875 offset_ptr->constant = 0; /*?*/
3878 offset_ptr->constant =
3879 #ifdef ARGS_GROW_DOWNWARD
3880 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
3882 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
3888 pad_below (offset_ptr, passed_mode, sizetree)
3889 struct args_size *offset_ptr;
3890 enum machine_mode passed_mode;
3893 if (passed_mode != BLKmode)
3895 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
3896 offset_ptr->constant
3897 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
3898 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
3899 - GET_MODE_SIZE (passed_mode));
3903 if (TREE_CODE (sizetree) != INTEGER_CST
3904 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
3906 /* Round the size up to multiple of PARM_BOUNDARY bits. */
3907 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
3909 ADD_PARM_SIZE (*offset_ptr, s2);
3910 SUB_PARM_SIZE (*offset_ptr, sizetree);
3916 round_down (value, divisor)
3920 return size_binop (MULT_EXPR,
3921 size_binop (FLOOR_DIV_EXPR, value, size_int (divisor)),
3922 size_int (divisor));
3925 /* Walk the tree of blocks describing the binding levels within a function
3926 and warn about uninitialized variables.
3927 This is done after calling flow_analysis and before global_alloc
3928 clobbers the pseudo-regs to hard regs. */
3931 uninitialized_vars_warning (block)
3934 register tree decl, sub;
3935 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
3937 if (TREE_CODE (decl) == VAR_DECL
3938 /* These warnings are unreliable for and aggregates
3939 because assigning the fields one by one can fail to convince
3940 flow.c that the entire aggregate was initialized.
3941 Unions are troublesome because members may be shorter. */
3942 && TREE_CODE (TREE_TYPE (decl)) != RECORD_TYPE
3943 && TREE_CODE (TREE_TYPE (decl)) != UNION_TYPE
3944 && TREE_CODE (TREE_TYPE (decl)) != QUAL_UNION_TYPE
3945 && TREE_CODE (TREE_TYPE (decl)) != ARRAY_TYPE
3946 && DECL_RTL (decl) != 0
3947 && GET_CODE (DECL_RTL (decl)) == REG
3948 && regno_uninitialized (REGNO (DECL_RTL (decl))))
3949 warning_with_decl (decl,
3950 "`%s' may be used uninitialized in this function");
3951 if (TREE_CODE (decl) == VAR_DECL
3952 && DECL_RTL (decl) != 0
3953 && GET_CODE (DECL_RTL (decl)) == REG
3954 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
3955 warning_with_decl (decl,
3956 "variable `%s' may be clobbered by `longjmp' or `vfork'");
3958 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
3959 uninitialized_vars_warning (sub);
3962 /* Do the appropriate part of uninitialized_vars_warning
3963 but for arguments instead of local variables. */
3966 setjmp_args_warning (block)
3970 for (decl = DECL_ARGUMENTS (current_function_decl);
3971 decl; decl = TREE_CHAIN (decl))
3972 if (DECL_RTL (decl) != 0
3973 && GET_CODE (DECL_RTL (decl)) == REG
3974 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
3975 warning_with_decl (decl, "argument `%s' may be clobbered by `longjmp' or `vfork'");
3978 /* If this function call setjmp, put all vars into the stack
3979 unless they were declared `register'. */
3982 setjmp_protect (block)
3985 register tree decl, sub;
3986 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
3987 if ((TREE_CODE (decl) == VAR_DECL
3988 || TREE_CODE (decl) == PARM_DECL)
3989 && DECL_RTL (decl) != 0
3990 && GET_CODE (DECL_RTL (decl)) == REG
3991 /* If this variable came from an inline function, it must be
3992 that it's life doesn't overlap the setjmp. If there was a
3993 setjmp in the function, it would already be in memory. We
3994 must exclude such variable because their DECL_RTL might be
3995 set to strange things such as virtual_stack_vars_rtx. */
3996 && ! DECL_FROM_INLINE (decl)
3998 #ifdef NON_SAVING_SETJMP
3999 /* If longjmp doesn't restore the registers,
4000 don't put anything in them. */
4004 ! DECL_REGISTER (decl)))
4005 put_var_into_stack (decl);
4006 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
4007 setjmp_protect (sub);
4010 /* Like the previous function, but for args instead of local variables. */
4013 setjmp_protect_args ()
4015 register tree decl, sub;
4016 for (decl = DECL_ARGUMENTS (current_function_decl);
4017 decl; decl = TREE_CHAIN (decl))
4018 if ((TREE_CODE (decl) == VAR_DECL
4019 || TREE_CODE (decl) == PARM_DECL)
4020 && DECL_RTL (decl) != 0
4021 && GET_CODE (DECL_RTL (decl)) == REG
4023 /* If longjmp doesn't restore the registers,
4024 don't put anything in them. */
4025 #ifdef NON_SAVING_SETJMP
4029 ! DECL_REGISTER (decl)))
4030 put_var_into_stack (decl);
4033 /* Return the context-pointer register corresponding to DECL,
4034 or 0 if it does not need one. */
4037 lookup_static_chain (decl)
4040 tree context = decl_function_context (decl);
4046 /* We treat inline_function_decl as an alias for the current function
4047 because that is the inline function whose vars, types, etc.
4048 are being merged into the current function.
4049 See expand_inline_function. */
4050 if (context == current_function_decl || context == inline_function_decl)
4051 return virtual_stack_vars_rtx;
4053 for (link = context_display; link; link = TREE_CHAIN (link))
4054 if (TREE_PURPOSE (link) == context)
4055 return RTL_EXPR_RTL (TREE_VALUE (link));
4060 /* Convert a stack slot address ADDR for variable VAR
4061 (from a containing function)
4062 into an address valid in this function (using a static chain). */
4065 fix_lexical_addr (addr, var)
4071 tree context = decl_function_context (var);
4072 struct function *fp;
4075 /* If this is the present function, we need not do anything. */
4076 if (context == current_function_decl || context == inline_function_decl)
4079 for (fp = outer_function_chain; fp; fp = fp->next)
4080 if (fp->decl == context)
4086 /* Decode given address as base reg plus displacement. */
4087 if (GET_CODE (addr) == REG)
4088 basereg = addr, displacement = 0;
4089 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
4090 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
4094 /* We accept vars reached via the containing function's
4095 incoming arg pointer and via its stack variables pointer. */
4096 if (basereg == fp->internal_arg_pointer)
4098 /* If reached via arg pointer, get the arg pointer value
4099 out of that function's stack frame.
4101 There are two cases: If a separate ap is needed, allocate a
4102 slot in the outer function for it and dereference it that way.
4103 This is correct even if the real ap is actually a pseudo.
4104 Otherwise, just adjust the offset from the frame pointer to
4107 #ifdef NEED_SEPARATE_AP
4110 if (fp->arg_pointer_save_area == 0)
4111 fp->arg_pointer_save_area
4112 = assign_outer_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0, fp);
4114 addr = fix_lexical_addr (XEXP (fp->arg_pointer_save_area, 0), var);
4115 addr = memory_address (Pmode, addr);
4117 base = copy_to_reg (gen_rtx (MEM, Pmode, addr));
4119 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
4120 base = lookup_static_chain (var);
4124 else if (basereg == virtual_stack_vars_rtx)
4126 /* This is the same code as lookup_static_chain, duplicated here to
4127 avoid an extra call to decl_function_context. */
4130 for (link = context_display; link; link = TREE_CHAIN (link))
4131 if (TREE_PURPOSE (link) == context)
4133 base = RTL_EXPR_RTL (TREE_VALUE (link));
4141 /* Use same offset, relative to appropriate static chain or argument
4143 return plus_constant (base, displacement);
4146 /* Return the address of the trampoline for entering nested fn FUNCTION.
4147 If necessary, allocate a trampoline (in the stack frame)
4148 and emit rtl to initialize its contents (at entry to this function). */
4151 trampoline_address (function)
4157 struct function *fp;
4160 /* Find an existing trampoline and return it. */
4161 for (link = trampoline_list; link; link = TREE_CHAIN (link))
4162 if (TREE_PURPOSE (link) == function)
4163 return XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0);
4164 for (fp = outer_function_chain; fp; fp = fp->next)
4165 for (link = fp->trampoline_list; link; link = TREE_CHAIN (link))
4166 if (TREE_PURPOSE (link) == function)
4168 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
4170 return round_trampoline_addr (tramp);
4173 /* None exists; we must make one. */
4175 /* Find the `struct function' for the function containing FUNCTION. */
4177 fn_context = decl_function_context (function);
4178 if (fn_context != current_function_decl)
4179 for (fp = outer_function_chain; fp; fp = fp->next)
4180 if (fp->decl == fn_context)
4183 /* Allocate run-time space for this trampoline
4184 (usually in the defining function's stack frame). */
4185 #ifdef ALLOCATE_TRAMPOLINE
4186 tramp = ALLOCATE_TRAMPOLINE (fp);
4188 /* If rounding needed, allocate extra space
4189 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
4190 #ifdef TRAMPOLINE_ALIGNMENT
4191 #define TRAMPOLINE_REAL_SIZE (TRAMPOLINE_SIZE + TRAMPOLINE_ALIGNMENT - 1)
4193 #define TRAMPOLINE_REAL_SIZE (TRAMPOLINE_SIZE)
4196 tramp = assign_outer_stack_local (BLKmode, TRAMPOLINE_REAL_SIZE, 0, fp);
4198 tramp = assign_stack_local (BLKmode, TRAMPOLINE_REAL_SIZE, 0);
4201 /* Record the trampoline for reuse and note it for later initialization
4202 by expand_function_end. */
4205 push_obstacks (fp->function_maybepermanent_obstack,
4206 fp->function_maybepermanent_obstack);
4207 rtlexp = make_node (RTL_EXPR);
4208 RTL_EXPR_RTL (rtlexp) = tramp;
4209 fp->trampoline_list = tree_cons (function, rtlexp, fp->trampoline_list);
4214 /* Make the RTL_EXPR node temporary, not momentary, so that the
4215 trampoline_list doesn't become garbage. */
4216 int momentary = suspend_momentary ();
4217 rtlexp = make_node (RTL_EXPR);
4218 resume_momentary (momentary);
4220 RTL_EXPR_RTL (rtlexp) = tramp;
4221 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
4224 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
4225 return round_trampoline_addr (tramp);
4228 /* Given a trampoline address,
4229 round it to multiple of TRAMPOLINE_ALIGNMENT. */
4232 round_trampoline_addr (tramp)
4235 #ifdef TRAMPOLINE_ALIGNMENT
4236 /* Round address up to desired boundary. */
4237 rtx temp = gen_reg_rtx (Pmode);
4238 temp = expand_binop (Pmode, add_optab, tramp,
4239 GEN_INT (TRAMPOLINE_ALIGNMENT - 1),
4240 temp, 0, OPTAB_LIB_WIDEN);
4241 tramp = expand_binop (Pmode, and_optab, temp,
4242 GEN_INT (- TRAMPOLINE_ALIGNMENT),
4243 temp, 0, OPTAB_LIB_WIDEN);
4248 /* The functions identify_blocks and reorder_blocks provide a way to
4249 reorder the tree of BLOCK nodes, for optimizers that reshuffle or
4250 duplicate portions of the RTL code. Call identify_blocks before
4251 changing the RTL, and call reorder_blocks after. */
4253 static int all_blocks ();
4254 static tree blocks_nreverse ();
4256 /* Put all this function's BLOCK nodes into a vector, and return it.
4257 Also store in each NOTE for the beginning or end of a block
4258 the index of that block in the vector.
4259 The arguments are TOP_BLOCK, the top-level block of the function,
4260 and INSNS, the insn chain of the function. */
4263 identify_blocks (top_block, insns)
4271 int next_block_number = 0;
4272 int current_block_number = 0;
4278 n_blocks = all_blocks (top_block, 0);
4279 block_vector = (tree *) xmalloc (n_blocks * sizeof (tree));
4280 block_stack = (int *) alloca (n_blocks * sizeof (int));
4282 all_blocks (top_block, block_vector);
4284 for (insn = insns; insn; insn = NEXT_INSN (insn))
4285 if (GET_CODE (insn) == NOTE)
4287 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
4289 block_stack[depth++] = current_block_number;
4290 current_block_number = next_block_number;
4291 NOTE_BLOCK_NUMBER (insn) = next_block_number++;
4293 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
4295 current_block_number = block_stack[--depth];
4296 NOTE_BLOCK_NUMBER (insn) = current_block_number;
4300 return block_vector;
4303 /* Given BLOCK_VECTOR which was returned by identify_blocks,
4304 and a revised instruction chain, rebuild the tree structure
4305 of BLOCK nodes to correspond to the new order of RTL.
4306 The new block tree is inserted below TOP_BLOCK.
4307 Returns the current top-level block. */
4310 reorder_blocks (block_vector, top_block, insns)
4315 tree current_block = top_block;
4318 if (block_vector == 0)
4321 /* Prune the old tree away, so that it doesn't get in the way. */
4322 BLOCK_SUBBLOCKS (current_block) = 0;
4324 for (insn = insns; insn; insn = NEXT_INSN (insn))
4325 if (GET_CODE (insn) == NOTE)
4327 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
4329 tree block = block_vector[NOTE_BLOCK_NUMBER (insn)];
4330 /* If we have seen this block before, copy it. */
4331 if (TREE_ASM_WRITTEN (block))
4332 block = copy_node (block);
4333 BLOCK_SUBBLOCKS (block) = 0;
4334 TREE_ASM_WRITTEN (block) = 1;
4335 BLOCK_SUPERCONTEXT (block) = current_block;
4336 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
4337 BLOCK_SUBBLOCKS (current_block) = block;
4338 current_block = block;
4339 NOTE_SOURCE_FILE (insn) = 0;
4341 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
4343 BLOCK_SUBBLOCKS (current_block)
4344 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
4345 current_block = BLOCK_SUPERCONTEXT (current_block);
4346 NOTE_SOURCE_FILE (insn) = 0;
4350 return current_block;
4353 /* Reverse the order of elements in the chain T of blocks,
4354 and return the new head of the chain (old last element). */
4360 register tree prev = 0, decl, next;
4361 for (decl = t; decl; decl = next)
4363 next = BLOCK_CHAIN (decl);
4364 BLOCK_CHAIN (decl) = prev;
4370 /* Count the subblocks of BLOCK, and list them all into the vector VECTOR.
4371 Also clear TREE_ASM_WRITTEN in all blocks. */
4374 all_blocks (block, vector)
4381 TREE_ASM_WRITTEN (block) = 0;
4382 /* Record this block. */
4386 /* Record the subblocks, and their subblocks. */
4387 for (subblocks = BLOCK_SUBBLOCKS (block);
4388 subblocks; subblocks = BLOCK_CHAIN (subblocks))
4389 n_blocks += all_blocks (subblocks, vector ? vector + n_blocks : 0);
4394 /* Build bytecode call descriptor for function SUBR. */
4396 bc_build_calldesc (subr)
4399 tree calldesc = 0, arg;
4402 /* Build the argument description vector in reverse order. */
4403 DECL_ARGUMENTS (subr) = nreverse (DECL_ARGUMENTS (subr));
4406 for (arg = DECL_ARGUMENTS (subr); arg; arg = TREE_CHAIN (arg))
4410 calldesc = tree_cons ((tree) 0, size_in_bytes (TREE_TYPE (arg)), calldesc);
4411 calldesc = tree_cons ((tree) 0, bc_runtime_type_code (TREE_TYPE (arg)), calldesc);
4414 DECL_ARGUMENTS (subr) = nreverse (DECL_ARGUMENTS (subr));
4416 /* Prepend the function's return type. */
4417 calldesc = tree_cons ((tree) 0,
4418 size_in_bytes (TREE_TYPE (TREE_TYPE (subr))),
4421 calldesc = tree_cons ((tree) 0,
4422 bc_runtime_type_code (TREE_TYPE (TREE_TYPE (subr))),
4425 /* Prepend the arg count. */
4426 calldesc = tree_cons ((tree) 0, build_int_2 (nargs, 0), calldesc);
4428 /* Output the call description vector and get its address. */
4429 calldesc = build_nt (CONSTRUCTOR, (tree) 0, calldesc);
4430 TREE_TYPE (calldesc) = build_array_type (integer_type_node,
4431 build_index_type (build_int_2 (nargs * 2, 0)));
4433 return output_constant_def (calldesc);
4437 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
4438 and initialize static variables for generating RTL for the statements
4442 init_function_start (subr, filename, line)
4449 if (output_bytecode)
4451 this_function_decl = subr;
4452 this_function_calldesc = bc_build_calldesc (subr);
4453 local_vars_size = 0;
4455 max_stack_depth = 0;
4456 stmt_expr_depth = 0;
4460 init_stmt_for_function ();
4462 cse_not_expected = ! optimize;
4464 /* Caller save not needed yet. */
4465 caller_save_needed = 0;
4467 /* No stack slots have been made yet. */
4468 stack_slot_list = 0;
4470 /* There is no stack slot for handling nonlocal gotos. */
4471 nonlocal_goto_handler_slot = 0;
4472 nonlocal_goto_stack_level = 0;
4474 /* No labels have been declared for nonlocal use. */
4475 nonlocal_labels = 0;
4477 /* No function calls so far in this function. */
4478 function_call_count = 0;
4480 /* No parm regs have been allocated.
4481 (This is important for output_inline_function.) */
4482 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4484 /* Initialize the RTL mechanism. */
4487 /* Initialize the queue of pending postincrement and postdecrements,
4488 and some other info in expr.c. */
4491 /* We haven't done register allocation yet. */
4494 init_const_rtx_hash_table ();
4496 current_function_name = (*decl_printable_name) (subr, &junk);
4498 /* Nonzero if this is a nested function that uses a static chain. */
4500 current_function_needs_context
4501 = (decl_function_context (current_function_decl) != 0);
4503 /* Set if a call to setjmp is seen. */
4504 current_function_calls_setjmp = 0;
4506 /* Set if a call to longjmp is seen. */
4507 current_function_calls_longjmp = 0;
4509 current_function_calls_alloca = 0;
4510 current_function_has_nonlocal_label = 0;
4511 current_function_has_nonlocal_goto = 0;
4512 current_function_contains_functions = 0;
4514 current_function_returns_pcc_struct = 0;
4515 current_function_returns_struct = 0;
4516 current_function_epilogue_delay_list = 0;
4517 current_function_uses_const_pool = 0;
4518 current_function_uses_pic_offset_table = 0;
4520 /* We have not yet needed to make a label to jump to for tail-recursion. */
4521 tail_recursion_label = 0;
4523 /* We haven't had a need to make a save area for ap yet. */
4525 arg_pointer_save_area = 0;
4527 /* No stack slots allocated yet. */
4530 /* No SAVE_EXPRs in this function yet. */
4533 /* No RTL_EXPRs in this function yet. */
4536 /* We have not allocated any temporaries yet. */
4538 temp_slot_level = 0;
4540 /* Within function body, compute a type's size as soon it is laid out. */
4541 immediate_size_expand++;
4543 /* We haven't made any trampolines for this function yet. */
4544 trampoline_list = 0;
4546 init_pending_stack_adjust ();
4547 inhibit_defer_pop = 0;
4549 current_function_outgoing_args_size = 0;
4551 /* Initialize the insn lengths. */
4552 init_insn_lengths ();
4554 /* Prevent ever trying to delete the first instruction of a function.
4555 Also tell final how to output a linenum before the function prologue. */
4556 emit_line_note (filename, line);
4558 /* Make sure first insn is a note even if we don't want linenums.
4559 This makes sure the first insn will never be deleted.
4560 Also, final expects a note to appear there. */
4561 emit_note (NULL_PTR, NOTE_INSN_DELETED);
4563 /* Set flags used by final.c. */
4564 if (aggregate_value_p (DECL_RESULT (subr)))
4566 #ifdef PCC_STATIC_STRUCT_RETURN
4567 current_function_returns_pcc_struct = 1;
4569 current_function_returns_struct = 1;
4572 /* Warn if this value is an aggregate type,
4573 regardless of which calling convention we are using for it. */
4574 if (warn_aggregate_return
4575 && (TREE_CODE (TREE_TYPE (DECL_RESULT (subr))) == RECORD_TYPE
4576 || TREE_CODE (TREE_TYPE (DECL_RESULT (subr))) == UNION_TYPE
4577 || TREE_CODE (TREE_TYPE (DECL_RESULT (subr))) == QUAL_UNION_TYPE
4578 || TREE_CODE (TREE_TYPE (DECL_RESULT (subr))) == ARRAY_TYPE))
4579 warning ("function returns an aggregate");
4581 current_function_returns_pointer
4582 = (TREE_CODE (TREE_TYPE (DECL_RESULT (subr))) == POINTER_TYPE);
4584 /* Indicate that we need to distinguish between the return value of the
4585 present function and the return value of a function being called. */
4586 rtx_equal_function_value_matters = 1;
4588 /* Indicate that we have not instantiated virtual registers yet. */
4589 virtuals_instantiated = 0;
4591 /* Indicate we have no need of a frame pointer yet. */
4592 frame_pointer_needed = 0;
4594 /* By default assume not varargs. */
4595 current_function_varargs = 0;
4598 /* Indicate that the current function uses extra args
4599 not explicitly mentioned in the argument list in any fashion. */
4604 current_function_varargs = 1;
4607 /* Expand a call to __main at the beginning of a possible main function. */
4610 expand_main_function ()
4612 if (!output_bytecode)
4614 /* The zero below avoids a possible parse error */
4616 #if !defined (INIT_SECTION_ASM_OP) || defined (INVOKE__main)
4617 emit_library_call (gen_rtx (SYMBOL_REF, Pmode, NAME__MAIN), 0,
4619 #endif /* not INIT_SECTION_ASM_OP or INVOKE__main */
4623 extern struct obstack permanent_obstack;
4625 /* Expand start of bytecode function. See comment at
4626 expand_function_start below for details. */
4629 bc_expand_function_start (subr, parms_have_cleanups)
4631 int parms_have_cleanups;
4633 char label[20], *name;
4638 if (TREE_PUBLIC (subr))
4639 bc_globalize_label (IDENTIFIER_POINTER (DECL_NAME (subr)));
4641 #ifdef DEBUG_PRINT_CODE
4642 fprintf (stderr, "\n<func %s>\n", IDENTIFIER_POINTER (DECL_NAME (subr)));
4645 for (argsz = 0, thisarg = DECL_ARGUMENTS (subr); thisarg; thisarg = TREE_CHAIN (thisarg))
4647 if (DECL_RTL (thisarg))
4648 abort (); /* Should be NULL here I think. */
4649 else if (TREE_CONSTANT (DECL_SIZE (thisarg)))
4651 DECL_RTL (thisarg) = bc_gen_rtx ((char *) 0, argsz, (struct bc_label *) 0);
4652 argsz += TREE_INT_CST_LOW (DECL_SIZE (thisarg));
4656 /* Variable-sized objects are pointers to their storage. */
4657 DECL_RTL (thisarg) = bc_gen_rtx ((char *) 0, argsz, (struct bc_label *) 0);
4658 argsz += POINTER_SIZE;
4662 bc_begin_function (bc_xstrdup (IDENTIFIER_POINTER (DECL_NAME (subr))));
4664 ASM_GENERATE_INTERNAL_LABEL (label, "LX", nlab);
4667 name = (char *) obstack_copy0 (&permanent_obstack, label, strlen (label));
4668 this_function_callinfo = bc_gen_rtx (name, 0, (struct bc_label *) 0);
4669 this_function_bytecode =
4670 bc_emit_trampoline (BYTECODE_LABEL (this_function_callinfo));
4674 /* Expand end of bytecode function. See details the comment of
4675 expand_function_end(), below. */
4678 bc_expand_function_end ()
4682 expand_null_return ();
4684 /* Emit any fixup code. This must be done before the call to
4685 to BC_END_FUNCTION (), since that will cause the bytecode
4686 segment to be finished off and closed. */
4688 fixup_gotos (0, 0, 0, 0, 0);
4690 ptrconsts = bc_end_function ();
4692 bc_align_const (2 /* INT_ALIGN */);
4694 /* If this changes also make sure to change bc-interp.h! */
4696 bc_emit_const_labeldef (BYTECODE_LABEL (this_function_callinfo));
4697 bc_emit_const ((char *) &max_stack_depth, sizeof max_stack_depth);
4698 bc_emit_const ((char *) &local_vars_size, sizeof local_vars_size);
4699 bc_emit_const_labelref (this_function_bytecode, 0);
4700 bc_emit_const_labelref (ptrconsts, 0);
4701 bc_emit_const_labelref (BYTECODE_LABEL (this_function_calldesc), 0);
4705 /* Start the RTL for a new function, and set variables used for
4707 SUBR is the FUNCTION_DECL node.
4708 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4709 the function's parameters, which must be run at any return statement. */
4712 expand_function_start (subr, parms_have_cleanups)
4714 int parms_have_cleanups;
4720 if (output_bytecode)
4722 bc_expand_function_start (subr, parms_have_cleanups);
4726 /* Make sure volatile mem refs aren't considered
4727 valid operands of arithmetic insns. */
4728 init_recog_no_volatile ();
4730 /* If function gets a static chain arg, store it in the stack frame.
4731 Do this first, so it gets the first stack slot offset. */
4732 if (current_function_needs_context)
4734 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
4735 emit_move_insn (last_ptr, static_chain_incoming_rtx);
4738 /* If the parameters of this function need cleaning up, get a label
4739 for the beginning of the code which executes those cleanups. This must
4740 be done before doing anything with return_label. */
4741 if (parms_have_cleanups)
4742 cleanup_label = gen_label_rtx ();
4746 /* Make the label for return statements to jump to, if this machine
4747 does not have a one-instruction return and uses an epilogue,
4748 or if it returns a structure, or if it has parm cleanups. */
4750 if (cleanup_label == 0 && HAVE_return
4751 && ! current_function_returns_pcc_struct
4752 && ! (current_function_returns_struct && ! optimize))
4755 return_label = gen_label_rtx ();
4757 return_label = gen_label_rtx ();
4760 /* Initialize rtx used to return the value. */
4761 /* Do this before assign_parms so that we copy the struct value address
4762 before any library calls that assign parms might generate. */
4764 /* Decide whether to return the value in memory or in a register. */
4765 if (aggregate_value_p (DECL_RESULT (subr)))
4767 /* Returning something that won't go in a register. */
4768 register rtx value_address;
4770 #ifdef PCC_STATIC_STRUCT_RETURN
4771 if (current_function_returns_pcc_struct)
4773 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
4774 value_address = assemble_static_space (size);
4779 /* Expect to be passed the address of a place to store the value.
4780 If it is passed as an argument, assign_parms will take care of
4782 if (struct_value_incoming_rtx)
4784 value_address = gen_reg_rtx (Pmode);
4785 emit_move_insn (value_address, struct_value_incoming_rtx);
4789 DECL_RTL (DECL_RESULT (subr))
4790 = gen_rtx (MEM, DECL_MODE (DECL_RESULT (subr)),
4793 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
4794 /* If return mode is void, this decl rtl should not be used. */
4795 DECL_RTL (DECL_RESULT (subr)) = 0;
4796 else if (parms_have_cleanups)
4798 /* If function will end with cleanup code for parms,
4799 compute the return values into a pseudo reg,
4800 which we will copy into the true return register
4801 after the cleanups are done. */
4803 enum machine_mode mode = DECL_MODE (DECL_RESULT (subr));
4804 #ifdef PROMOTE_FUNCTION_RETURN
4805 tree type = TREE_TYPE (DECL_RESULT (subr));
4806 int unsignedp = TREE_UNSIGNED (type);
4808 if (TREE_CODE (type) == INTEGER_TYPE || TREE_CODE (type) == ENUMERAL_TYPE
4809 || TREE_CODE (type) == BOOLEAN_TYPE || TREE_CODE (type) == CHAR_TYPE
4810 || TREE_CODE (type) == REAL_TYPE || TREE_CODE (type) == POINTER_TYPE
4811 || TREE_CODE (type) == OFFSET_TYPE)
4813 PROMOTE_MODE (mode, unsignedp, type);
4817 DECL_RTL (DECL_RESULT (subr)) = gen_reg_rtx (mode);
4820 /* Scalar, returned in a register. */
4822 #ifdef FUNCTION_OUTGOING_VALUE
4823 DECL_RTL (DECL_RESULT (subr))
4824 = FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (subr)), subr);
4826 DECL_RTL (DECL_RESULT (subr))
4827 = FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (subr)), subr);
4830 /* Mark this reg as the function's return value. */
4831 if (GET_CODE (DECL_RTL (DECL_RESULT (subr))) == REG)
4833 REG_FUNCTION_VALUE_P (DECL_RTL (DECL_RESULT (subr))) = 1;
4834 /* Needed because we may need to move this to memory
4835 in case it's a named return value whose address is taken. */
4836 DECL_REGISTER (DECL_RESULT (subr)) = 1;
4840 /* Initialize rtx for parameters and local variables.
4841 In some cases this requires emitting insns. */
4843 assign_parms (subr, 0);
4845 /* The following was moved from init_function_start.
4846 The move is supposed to make sdb output more accurate. */
4847 /* Indicate the beginning of the function body,
4848 as opposed to parm setup. */
4849 emit_note (NULL_PTR, NOTE_INSN_FUNCTION_BEG);
4851 /* If doing stupid allocation, mark parms as born here. */
4853 if (GET_CODE (get_last_insn ()) != NOTE)
4854 emit_note (NULL_PTR, NOTE_INSN_DELETED);
4855 parm_birth_insn = get_last_insn ();
4859 for (i = LAST_VIRTUAL_REGISTER + 1; i < max_parm_reg; i++)
4860 use_variable (regno_reg_rtx[i]);
4862 if (current_function_internal_arg_pointer != virtual_incoming_args_rtx)
4863 use_variable (current_function_internal_arg_pointer);
4866 /* Fetch static chain values for containing functions. */
4867 tem = decl_function_context (current_function_decl);
4868 /* If not doing stupid register allocation, then start off with the static
4869 chain pointer in a pseudo register. Otherwise, we use the stack
4870 address that was generated above. */
4871 if (tem && ! obey_regdecls)
4872 last_ptr = copy_to_reg (static_chain_incoming_rtx);
4873 context_display = 0;
4876 tree rtlexp = make_node (RTL_EXPR);
4878 RTL_EXPR_RTL (rtlexp) = last_ptr;
4879 context_display = tree_cons (tem, rtlexp, context_display);
4880 tem = decl_function_context (tem);
4883 /* Chain thru stack frames, assuming pointer to next lexical frame
4884 is found at the place we always store it. */
4885 #ifdef FRAME_GROWS_DOWNWARD
4886 last_ptr = plus_constant (last_ptr, - GET_MODE_SIZE (Pmode));
4888 last_ptr = copy_to_reg (gen_rtx (MEM, Pmode,
4889 memory_address (Pmode, last_ptr)));
4891 /* If we are not optimizing, ensure that we know that this
4892 piece of context is live over the entire function. */
4894 save_expr_regs = gen_rtx (EXPR_LIST, VOIDmode, last_ptr,
4898 /* After the display initializations is where the tail-recursion label
4899 should go, if we end up needing one. Ensure we have a NOTE here
4900 since some things (like trampolines) get placed before this. */
4901 tail_recursion_reentry = emit_note (NULL_PTR, NOTE_INSN_DELETED);
4903 /* Evaluate now the sizes of any types declared among the arguments. */
4904 for (tem = nreverse (get_pending_sizes ()); tem; tem = TREE_CHAIN (tem))
4905 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode, 0);
4907 /* Make sure there is a line number after the function entry setup code. */
4908 force_next_line_note ();
4911 /* Generate RTL for the end of the current function.
4912 FILENAME and LINE are the current position in the source file.
4914 It is up to language-specific callers to do cleanups for parameters--
4915 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
4918 expand_function_end (filename, line, end_bindings)
4926 static rtx initial_trampoline;
4928 if (output_bytecode)
4930 bc_expand_function_end ();
4934 #ifdef NON_SAVING_SETJMP
4935 /* Don't put any variables in registers if we call setjmp
4936 on a machine that fails to restore the registers. */
4937 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
4939 setjmp_protect (DECL_INITIAL (current_function_decl));
4940 setjmp_protect_args ();
4944 /* Save the argument pointer if a save area was made for it. */
4945 if (arg_pointer_save_area)
4947 rtx x = gen_move_insn (arg_pointer_save_area, virtual_incoming_args_rtx);
4948 emit_insn_before (x, tail_recursion_reentry);
4951 /* Initialize any trampolines required by this function. */
4952 for (link = trampoline_list; link; link = TREE_CHAIN (link))
4954 tree function = TREE_PURPOSE (link);
4955 rtx context = lookup_static_chain (function);
4956 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
4959 /* First make sure this compilation has a template for
4960 initializing trampolines. */
4961 if (initial_trampoline == 0)
4963 end_temporary_allocation ();
4965 = gen_rtx (MEM, BLKmode, assemble_trampoline_template ());
4966 resume_temporary_allocation ();
4969 /* Generate insns to initialize the trampoline. */
4971 tramp = change_address (initial_trampoline, BLKmode,
4972 round_trampoline_addr (XEXP (tramp, 0)));
4973 emit_block_move (tramp, initial_trampoline, GEN_INT (TRAMPOLINE_SIZE),
4974 FUNCTION_BOUNDARY / BITS_PER_UNIT);
4975 INITIALIZE_TRAMPOLINE (XEXP (tramp, 0),
4976 XEXP (DECL_RTL (function), 0), context);
4980 /* Put those insns at entry to the containing function (this one). */
4981 emit_insns_before (seq, tail_recursion_reentry);
4984 #if 0 /* I think unused parms are legitimate enough. */
4985 /* Warn about unused parms. */
4990 for (decl = DECL_ARGUMENTS (current_function_decl);
4991 decl; decl = TREE_CHAIN (decl))
4992 if (! TREE_USED (decl) && TREE_CODE (decl) == VAR_DECL)
4993 warning_with_decl (decl, "unused parameter `%s'");
4997 /* Delete handlers for nonlocal gotos if nothing uses them. */
4998 if (nonlocal_goto_handler_slot != 0 && !current_function_has_nonlocal_label)
5001 /* End any sequences that failed to be closed due to syntax errors. */
5002 while (in_sequence_p ())
5005 /* Outside function body, can't compute type's actual size
5006 until next function's body starts. */
5007 immediate_size_expand--;
5009 /* If doing stupid register allocation,
5010 mark register parms as dying here. */
5015 for (i = LAST_VIRTUAL_REGISTER + 1; i < max_parm_reg; i++)
5016 use_variable (regno_reg_rtx[i]);
5018 /* Likewise for the regs of all the SAVE_EXPRs in the function. */
5020 for (tem = save_expr_regs; tem; tem = XEXP (tem, 1))
5022 use_variable (XEXP (tem, 0));
5023 use_variable_after (XEXP (tem, 0), parm_birth_insn);
5026 if (current_function_internal_arg_pointer != virtual_incoming_args_rtx)
5027 use_variable (current_function_internal_arg_pointer);
5030 clear_pending_stack_adjust ();
5031 do_pending_stack_adjust ();
5033 /* Mark the end of the function body.
5034 If control reaches this insn, the function can drop through
5035 without returning a value. */
5036 emit_note (NULL_PTR, NOTE_INSN_FUNCTION_END);
5038 /* Output a linenumber for the end of the function.
5039 SDB depends on this. */
5040 emit_line_note_force (filename, line);
5042 /* Output the label for the actual return from the function,
5043 if one is expected. This happens either because a function epilogue
5044 is used instead of a return instruction, or because a return was done
5045 with a goto in order to run local cleanups, or because of pcc-style
5046 structure returning. */
5049 emit_label (return_label);
5051 /* C++ uses this. */
5053 expand_end_bindings (0, 0, 0);
5055 /* If we had calls to alloca, and this machine needs
5056 an accurate stack pointer to exit the function,
5057 insert some code to save and restore the stack pointer. */
5058 #ifdef EXIT_IGNORE_STACK
5059 if (! EXIT_IGNORE_STACK)
5061 if (current_function_calls_alloca)
5065 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
5066 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
5069 /* If scalar return value was computed in a pseudo-reg,
5070 copy that to the hard return register. */
5071 if (DECL_RTL (DECL_RESULT (current_function_decl)) != 0
5072 && GET_CODE (DECL_RTL (DECL_RESULT (current_function_decl))) == REG
5073 && (REGNO (DECL_RTL (DECL_RESULT (current_function_decl)))
5074 >= FIRST_PSEUDO_REGISTER))
5076 rtx real_decl_result;
5078 #ifdef FUNCTION_OUTGOING_VALUE
5080 = FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl)),
5081 current_function_decl);
5084 = FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl)),
5085 current_function_decl);
5087 REG_FUNCTION_VALUE_P (real_decl_result) = 1;
5088 emit_move_insn (real_decl_result,
5089 DECL_RTL (DECL_RESULT (current_function_decl)));
5090 emit_insn (gen_rtx (USE, VOIDmode, real_decl_result));
5093 /* If returning a structure, arrange to return the address of the value
5094 in a place where debuggers expect to find it.
5096 If returning a structure PCC style,
5097 the caller also depends on this value.
5098 And current_function_returns_pcc_struct is not necessarily set. */
5099 if (current_function_returns_struct
5100 || current_function_returns_pcc_struct)
5102 rtx value_address = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
5103 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
5104 #ifdef FUNCTION_OUTGOING_VALUE
5106 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
5107 current_function_decl);
5110 = FUNCTION_VALUE (build_pointer_type (type),
5111 current_function_decl);
5114 /* Mark this as a function return value so integrate will delete the
5115 assignment and USE below when inlining this function. */
5116 REG_FUNCTION_VALUE_P (outgoing) = 1;
5118 emit_move_insn (outgoing, value_address);
5119 use_variable (outgoing);
5122 /* Output a return insn if we are using one.
5123 Otherwise, let the rtl chain end here, to drop through
5124 into the epilogue. */
5129 emit_jump_insn (gen_return ());
5134 /* Fix up any gotos that jumped out to the outermost
5135 binding level of the function.
5136 Must follow emitting RETURN_LABEL. */
5138 /* If you have any cleanups to do at this point,
5139 and they need to create temporary variables,
5140 then you will lose. */
5141 fixup_gotos (NULL_PTR, NULL_RTX, NULL_TREE, get_insns (), 0);
5144 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
5146 static int *prologue;
5147 static int *epilogue;
5149 /* Create an array that records the INSN_UIDs of INSNS (either a sequence
5150 or a single insn). */
5153 record_insns (insns)
5158 if (GET_CODE (insns) == SEQUENCE)
5160 int len = XVECLEN (insns, 0);
5161 vec = (int *) oballoc ((len + 1) * sizeof (int));
5164 vec[len] = INSN_UID (XVECEXP (insns, 0, len));
5168 vec = (int *) oballoc (2 * sizeof (int));
5169 vec[0] = INSN_UID (insns);
5175 /* Determine how many INSN_UIDs in VEC are part of INSN. */
5178 contains (insn, vec)
5184 if (GET_CODE (insn) == INSN
5185 && GET_CODE (PATTERN (insn)) == SEQUENCE)
5188 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
5189 for (j = 0; vec[j]; j++)
5190 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == vec[j])
5196 for (j = 0; vec[j]; j++)
5197 if (INSN_UID (insn) == vec[j])
5203 /* Generate the prologe and epilogue RTL if the machine supports it. Thread
5204 this into place with notes indicating where the prologue ends and where
5205 the epilogue begins. Update the basic block information when possible. */
5208 thread_prologue_and_epilogue_insns (f)
5211 #ifdef HAVE_prologue
5214 rtx head, seq, insn;
5216 /* The first insn (a NOTE_INSN_DELETED) is followed by zero or more
5217 prologue insns and a NOTE_INSN_PROLOGUE_END. */
5218 emit_note_after (NOTE_INSN_PROLOGUE_END, f);
5219 seq = gen_prologue ();
5220 head = emit_insn_after (seq, f);
5222 /* Include the new prologue insns in the first block. Ignore them
5223 if they form a basic block unto themselves. */
5224 if (basic_block_head && n_basic_blocks
5225 && GET_CODE (basic_block_head[0]) != CODE_LABEL)
5226 basic_block_head[0] = NEXT_INSN (f);
5228 /* Retain a map of the prologue insns. */
5229 prologue = record_insns (GET_CODE (seq) == SEQUENCE ? seq : head);
5235 #ifdef HAVE_epilogue
5238 rtx insn = get_last_insn ();
5239 rtx prev = prev_nonnote_insn (insn);
5241 /* If we end with a BARRIER, we don't need an epilogue. */
5242 if (! (prev && GET_CODE (prev) == BARRIER))
5248 /* The last basic block ends with a NOTE_INSN_EPILOGUE_BEG, the
5249 epilogue insns, the USE insns at the end of a function,
5250 the jump insn that returns, and then a BARRIER. */
5252 /* Move the USE insns at the end of a function onto a list. */
5254 && GET_CODE (prev) == INSN
5255 && GET_CODE (PATTERN (prev)) == USE)
5258 prev = prev_nonnote_insn (prev);
5260 NEXT_INSN (PREV_INSN (tem)) = NEXT_INSN (tem);
5261 PREV_INSN (NEXT_INSN (tem)) = PREV_INSN (tem);
5265 NEXT_INSN (last_use) = tem;
5270 emit_barrier_after (insn);
5272 seq = gen_epilogue ();
5273 tail = emit_jump_insn_after (seq, insn);
5275 /* Insert the USE insns immediately before the return insn, which
5276 must be the first instruction before the final barrier. */
5279 tem = prev_nonnote_insn (get_last_insn ());
5280 NEXT_INSN (PREV_INSN (tem)) = first_use;
5281 PREV_INSN (first_use) = PREV_INSN (tem);
5282 PREV_INSN (tem) = last_use;
5283 NEXT_INSN (last_use) = tem;
5286 emit_note_after (NOTE_INSN_EPILOGUE_BEG, insn);
5288 /* Include the new epilogue insns in the last block. Ignore
5289 them if they form a basic block unto themselves. */
5290 if (basic_block_end && n_basic_blocks
5291 && GET_CODE (basic_block_end[n_basic_blocks - 1]) != JUMP_INSN)
5292 basic_block_end[n_basic_blocks - 1] = tail;
5294 /* Retain a map of the epilogue insns. */
5295 epilogue = record_insns (GET_CODE (seq) == SEQUENCE ? seq : tail);
5303 /* Reposition the prologue-end and epilogue-begin notes after instruction
5304 scheduling and delayed branch scheduling. */
5307 reposition_prologue_and_epilogue_notes (f)
5310 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
5311 /* Reposition the prologue and epilogue notes. */
5319 register rtx insn, note = 0;
5321 /* Scan from the beginning until we reach the last prologue insn.
5322 We apparently can't depend on basic_block_{head,end} after
5324 for (len = 0; prologue[len]; len++)
5326 for (insn = f; len && insn; insn = NEXT_INSN (insn))
5328 if (GET_CODE (insn) == NOTE)
5330 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
5333 else if ((len -= contains (insn, prologue)) == 0)
5335 /* Find the prologue-end note if we haven't already, and
5336 move it to just after the last prologue insn. */
5339 for (note = insn; note = NEXT_INSN (note);)
5340 if (GET_CODE (note) == NOTE
5341 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
5344 next = NEXT_INSN (note);
5345 prev = PREV_INSN (note);
5347 NEXT_INSN (prev) = next;
5349 PREV_INSN (next) = prev;
5350 add_insn_after (note, insn);
5357 register rtx insn, note = 0;
5359 /* Scan from the end until we reach the first epilogue insn.
5360 We apparently can't depend on basic_block_{head,end} after
5362 for (len = 0; epilogue[len]; len++)
5364 for (insn = get_last_insn (); len && insn; insn = PREV_INSN (insn))
5366 if (GET_CODE (insn) == NOTE)
5368 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
5371 else if ((len -= contains (insn, epilogue)) == 0)
5373 /* Find the epilogue-begin note if we haven't already, and
5374 move it to just before the first epilogue insn. */
5377 for (note = insn; note = PREV_INSN (note);)
5378 if (GET_CODE (note) == NOTE
5379 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
5382 next = NEXT_INSN (note);
5383 prev = PREV_INSN (note);
5385 NEXT_INSN (prev) = next;
5387 PREV_INSN (next) = prev;
5388 add_insn_after (note, PREV_INSN (insn));
5393 #endif /* HAVE_prologue or HAVE_epilogue */