1 /* Expands front end tree to back end RTL for GNU C-Compiler
2 Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000 Free Software Foundation, Inc.
5 This file is part of GNU CC.
7 GNU CC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GNU CC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU CC; see the file COPYING. If not, write to
19 the Free Software Foundation, 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
23 /* This file handles the generation of rtl code from tree structure
24 at the level of the function as a whole.
25 It creates the rtl expressions for parameters and auto variables
26 and has full responsibility for allocating stack slots.
28 `expand_function_start' is called at the beginning of a function,
29 before the function body is parsed, and `expand_function_end' is
30 called after parsing the body.
32 Call `assign_stack_local' to allocate a stack slot for a local variable.
33 This is usually done during the RTL generation for the function body,
34 but it can also be done in the reload pass when a pseudo-register does
35 not get a hard register.
37 Call `put_var_into_stack' when you learn, belatedly, that a variable
38 previously given a pseudo-register must in fact go in the stack.
39 This function changes the DECL_RTL to be a stack slot instead of a reg
40 then scans all the RTL instructions so far generated to correct them. */
49 #include "insn-flags.h"
51 #include "insn-codes.h"
53 #include "hard-reg-set.h"
54 #include "insn-config.h"
57 #include "basic-block.h"
64 #ifndef TRAMPOLINE_ALIGNMENT
65 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
68 #ifndef LOCAL_ALIGNMENT
69 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
72 #if !defined (PREFERRED_STACK_BOUNDARY) && defined (STACK_BOUNDARY)
73 #define PREFERRED_STACK_BOUNDARY STACK_BOUNDARY
76 /* Some systems use __main in a way incompatible with its use in gcc, in these
77 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
78 give the same symbol without quotes for an alternative entry point. You
79 must define both, or neither. */
81 #define NAME__MAIN "__main"
82 #define SYMBOL__MAIN __main
85 /* Round a value to the lowest integer less than it that is a multiple of
86 the required alignment. Avoid using division in case the value is
87 negative. Assume the alignment is a power of two. */
88 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
90 /* Similar, but round to the next highest integer that meets the
92 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
94 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
95 during rtl generation. If they are different register numbers, this is
96 always true. It may also be true if
97 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
98 generation. See fix_lexical_addr for details. */
100 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
101 #define NEED_SEPARATE_AP
104 /* Nonzero if function being compiled doesn't contain any calls
105 (ignoring the prologue and epilogue). This is set prior to
106 local register allocation and is valid for the remaining
108 int current_function_is_leaf;
110 /* Nonzero if function being compiled doesn't modify the stack pointer
111 (ignoring the prologue and epilogue). This is only valid after
112 life_analysis has run. */
113 int current_function_sp_is_unchanging;
115 /* Nonzero if the function being compiled is a leaf function which only
116 uses leaf registers. This is valid after reload (specifically after
117 sched2) and is useful only if the port defines LEAF_REGISTERS. */
118 int current_function_uses_only_leaf_regs;
120 /* Nonzero once virtual register instantiation has been done.
121 assign_stack_local uses frame_pointer_rtx when this is nonzero. */
122 static int virtuals_instantiated;
124 /* These variables hold pointers to functions to
125 save and restore machine-specific data,
126 in push_function_context and pop_function_context. */
127 void (*init_machine_status) PARAMS ((struct function *));
128 void (*save_machine_status) PARAMS ((struct function *));
129 void (*restore_machine_status) PARAMS ((struct function *));
130 void (*mark_machine_status) PARAMS ((struct function *));
131 void (*free_machine_status) PARAMS ((struct function *));
133 /* Likewise, but for language-specific data. */
134 void (*init_lang_status) PARAMS ((struct function *));
135 void (*save_lang_status) PARAMS ((struct function *));
136 void (*restore_lang_status) PARAMS ((struct function *));
137 void (*mark_lang_status) PARAMS ((struct function *));
138 void (*free_lang_status) PARAMS ((struct function *));
140 /* The FUNCTION_DECL for an inline function currently being expanded. */
141 tree inline_function_decl;
143 /* The currently compiled function. */
144 struct function *cfun = 0;
146 /* Global list of all compiled functions. */
147 struct function *all_functions = 0;
149 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
150 static int *prologue;
151 static int *epilogue;
153 /* In order to evaluate some expressions, such as function calls returning
154 structures in memory, we need to temporarily allocate stack locations.
155 We record each allocated temporary in the following structure.
157 Associated with each temporary slot is a nesting level. When we pop up
158 one level, all temporaries associated with the previous level are freed.
159 Normally, all temporaries are freed after the execution of the statement
160 in which they were created. However, if we are inside a ({...}) grouping,
161 the result may be in a temporary and hence must be preserved. If the
162 result could be in a temporary, we preserve it if we can determine which
163 one it is in. If we cannot determine which temporary may contain the
164 result, all temporaries are preserved. A temporary is preserved by
165 pretending it was allocated at the previous nesting level.
167 Automatic variables are also assigned temporary slots, at the nesting
168 level where they are defined. They are marked a "kept" so that
169 free_temp_slots will not free them. */
173 /* Points to next temporary slot. */
174 struct temp_slot *next;
175 /* The rtx to used to reference the slot. */
177 /* The rtx used to represent the address if not the address of the
178 slot above. May be an EXPR_LIST if multiple addresses exist. */
180 /* The alignment (in bits) of the slot. */
182 /* The size, in units, of the slot. */
184 /* The alias set for the slot. If the alias set is zero, we don't
185 know anything about the alias set of the slot. We must only
186 reuse a slot if it is assigned an object of the same alias set.
187 Otherwise, the rest of the compiler may assume that the new use
188 of the slot cannot alias the old use of the slot, which is
189 false. If the slot has alias set zero, then we can't reuse the
190 slot at all, since we have no idea what alias set may have been
191 imposed on the memory. For example, if the stack slot is the
192 call frame for an inline functioned, we have no idea what alias
193 sets will be assigned to various pieces of the call frame. */
195 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
197 /* Non-zero if this temporary is currently in use. */
199 /* Non-zero if this temporary has its address taken. */
201 /* Nesting level at which this slot is being used. */
203 /* Non-zero if this should survive a call to free_temp_slots. */
205 /* The offset of the slot from the frame_pointer, including extra space
206 for alignment. This info is for combine_temp_slots. */
207 HOST_WIDE_INT base_offset;
208 /* The size of the slot, including extra space for alignment. This
209 info is for combine_temp_slots. */
210 HOST_WIDE_INT full_size;
213 /* This structure is used to record MEMs or pseudos used to replace VAR, any
214 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
215 maintain this list in case two operands of an insn were required to match;
216 in that case we must ensure we use the same replacement. */
218 struct fixup_replacement
222 struct fixup_replacement *next;
225 struct insns_for_mem_entry {
226 /* The KEY in HE will be a MEM. */
227 struct hash_entry he;
228 /* These are the INSNS which reference the MEM. */
232 /* Forward declarations. */
234 static rtx assign_stack_local_1 PARAMS ((enum machine_mode, HOST_WIDE_INT,
235 int, struct function *));
236 static rtx assign_stack_temp_for_type PARAMS ((enum machine_mode,
237 HOST_WIDE_INT, int, tree));
238 static struct temp_slot *find_temp_slot_from_address PARAMS ((rtx));
239 static void put_reg_into_stack PARAMS ((struct function *, rtx, tree,
240 enum machine_mode, enum machine_mode,
241 int, int, int, struct hash_table *));
242 static void fixup_var_refs PARAMS ((rtx, enum machine_mode, int,
243 struct hash_table *));
244 static struct fixup_replacement
245 *find_fixup_replacement PARAMS ((struct fixup_replacement **, rtx));
246 static void fixup_var_refs_insns PARAMS ((rtx, enum machine_mode, int,
247 rtx, int, struct hash_table *));
248 static void fixup_var_refs_1 PARAMS ((rtx, enum machine_mode, rtx *, rtx,
249 struct fixup_replacement **));
250 static rtx fixup_memory_subreg PARAMS ((rtx, rtx, int));
251 static rtx walk_fixup_memory_subreg PARAMS ((rtx, rtx, int));
252 static rtx fixup_stack_1 PARAMS ((rtx, rtx));
253 static void optimize_bit_field PARAMS ((rtx, rtx, rtx *));
254 static void instantiate_decls PARAMS ((tree, int));
255 static void instantiate_decls_1 PARAMS ((tree, int));
256 static void instantiate_decl PARAMS ((rtx, int, int));
257 static int instantiate_virtual_regs_1 PARAMS ((rtx *, rtx, int));
258 static void delete_handlers PARAMS ((void));
259 static void pad_to_arg_alignment PARAMS ((struct args_size *, int,
260 struct args_size *));
261 #ifndef ARGS_GROW_DOWNWARD
262 static void pad_below PARAMS ((struct args_size *, enum machine_mode,
265 #ifdef ARGS_GROW_DOWNWARD
266 static tree round_down PARAMS ((tree, int));
268 static rtx round_trampoline_addr PARAMS ((rtx));
269 static tree blocks_nreverse PARAMS ((tree));
270 static int all_blocks PARAMS ((tree, tree *));
271 /* We always define `record_insns' even if its not used so that we
272 can always export `prologue_epilogue_contains'. */
273 static int *record_insns PARAMS ((rtx)) ATTRIBUTE_UNUSED;
274 static int contains PARAMS ((rtx, int *));
276 static void emit_return_into_block PARAMS ((basic_block));
278 static void put_addressof_into_stack PARAMS ((rtx, struct hash_table *));
279 static boolean purge_addressof_1 PARAMS ((rtx *, rtx, int, int,
280 struct hash_table *));
281 static int is_addressof PARAMS ((rtx *, void *));
282 static struct hash_entry *insns_for_mem_newfunc PARAMS ((struct hash_entry *,
285 static unsigned long insns_for_mem_hash PARAMS ((hash_table_key));
286 static boolean insns_for_mem_comp PARAMS ((hash_table_key, hash_table_key));
287 static int insns_for_mem_walk PARAMS ((rtx *, void *));
288 static void compute_insns_for_mem PARAMS ((rtx, rtx, struct hash_table *));
289 static void mark_temp_slot PARAMS ((struct temp_slot *));
290 static void mark_function_status PARAMS ((struct function *));
291 static void mark_function_chain PARAMS ((void *));
292 static void prepare_function_start PARAMS ((void));
293 static void do_clobber_return_reg PARAMS ((rtx, void *));
294 static void do_use_return_reg PARAMS ((rtx, void *));
296 /* Pointer to chain of `struct function' for containing functions. */
297 struct function *outer_function_chain;
299 /* Given a function decl for a containing function,
300 return the `struct function' for it. */
303 find_function_data (decl)
308 for (p = outer_function_chain; p; p = p->next)
315 /* Save the current context for compilation of a nested function.
316 This is called from language-specific code. The caller should use
317 the save_lang_status callback to save any language-specific state,
318 since this function knows only about language-independent
322 push_function_context_to (context)
325 struct function *p, *context_data;
329 context_data = (context == current_function_decl
331 : find_function_data (context));
332 context_data->contains_functions = 1;
336 init_dummy_function_start ();
339 p->next = outer_function_chain;
340 outer_function_chain = p;
341 p->fixup_var_refs_queue = 0;
343 save_tree_status (p);
344 if (save_lang_status)
345 (*save_lang_status) (p);
346 if (save_machine_status)
347 (*save_machine_status) (p);
353 push_function_context ()
355 push_function_context_to (current_function_decl);
358 /* Restore the last saved context, at the end of a nested function.
359 This function is called from language-specific code. */
362 pop_function_context_from (context)
363 tree context ATTRIBUTE_UNUSED;
365 struct function *p = outer_function_chain;
366 struct var_refs_queue *queue;
367 struct var_refs_queue *next;
370 outer_function_chain = p->next;
372 current_function_decl = p->decl;
375 restore_tree_status (p);
376 restore_emit_status (p);
378 if (restore_machine_status)
379 (*restore_machine_status) (p);
380 if (restore_lang_status)
381 (*restore_lang_status) (p);
383 /* Finish doing put_var_into_stack for any of our variables
384 which became addressable during the nested function. */
385 for (queue = p->fixup_var_refs_queue; queue; queue = next)
388 fixup_var_refs (queue->modified, queue->promoted_mode,
389 queue->unsignedp, 0);
392 p->fixup_var_refs_queue = 0;
394 /* Reset variables that have known state during rtx generation. */
395 rtx_equal_function_value_matters = 1;
396 virtuals_instantiated = 0;
400 pop_function_context ()
402 pop_function_context_from (current_function_decl);
405 /* Clear out all parts of the state in F that can safely be discarded
406 after the function has been parsed, but not compiled, to let
407 garbage collection reclaim the memory. */
410 free_after_parsing (f)
413 /* f->expr->forced_labels is used by code generation. */
414 /* f->emit->regno_reg_rtx is used by code generation. */
415 /* f->varasm is used by code generation. */
416 /* f->eh->eh_return_stub_label is used by code generation. */
418 if (free_lang_status)
419 (*free_lang_status) (f);
420 free_stmt_status (f);
423 /* Clear out all parts of the state in F that can safely be discarded
424 after the function has been compiled, to let garbage collection
425 reclaim the memory. */
428 free_after_compilation (f)
432 free_expr_status (f);
433 free_emit_status (f);
434 free_varasm_status (f);
436 if (free_machine_status)
437 (*free_machine_status) (f);
439 if (f->x_parm_reg_stack_loc)
440 free (f->x_parm_reg_stack_loc);
442 f->arg_offset_rtx = NULL;
443 f->return_rtx = NULL;
444 f->internal_arg_pointer = NULL;
445 f->x_nonlocal_labels = NULL;
446 f->x_nonlocal_goto_handler_slots = NULL;
447 f->x_nonlocal_goto_handler_labels = NULL;
448 f->x_nonlocal_goto_stack_level = NULL;
449 f->x_cleanup_label = NULL;
450 f->x_return_label = NULL;
451 f->x_save_expr_regs = NULL;
452 f->x_stack_slot_list = NULL;
453 f->x_rtl_expr_chain = NULL;
454 f->x_tail_recursion_label = NULL;
455 f->x_tail_recursion_reentry = NULL;
456 f->x_arg_pointer_save_area = NULL;
457 f->x_context_display = NULL;
458 f->x_trampoline_list = NULL;
459 f->x_parm_birth_insn = NULL;
460 f->x_last_parm_insn = NULL;
461 f->x_parm_reg_stack_loc = NULL;
462 f->x_temp_slots = NULL;
463 f->fixup_var_refs_queue = NULL;
464 f->original_arg_vector = NULL;
465 f->original_decl_initial = NULL;
466 f->inl_last_parm_insn = NULL;
467 f->epilogue_delay_list = NULL;
471 /* Allocate fixed slots in the stack frame of the current function. */
473 /* Return size needed for stack frame based on slots so far allocated in
475 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
476 the caller may have to do that. */
479 get_func_frame_size (f)
482 #ifdef FRAME_GROWS_DOWNWARD
483 return -f->x_frame_offset;
485 return f->x_frame_offset;
489 /* Return size needed for stack frame based on slots so far allocated.
490 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
491 the caller may have to do that. */
495 return get_func_frame_size (cfun);
498 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
499 with machine mode MODE.
501 ALIGN controls the amount of alignment for the address of the slot:
502 0 means according to MODE,
503 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
504 positive specifies alignment boundary in bits.
506 We do not round to stack_boundary here.
508 FUNCTION specifies the function to allocate in. */
511 assign_stack_local_1 (mode, size, align, function)
512 enum machine_mode mode;
515 struct function *function;
517 register rtx x, addr;
518 int bigend_correction = 0;
521 /* Allocate in the memory associated with the function in whose frame
523 if (function != cfun)
524 push_obstacks (function->function_obstack,
525 function->function_maybepermanent_obstack);
531 alignment = GET_MODE_ALIGNMENT (mode);
533 alignment = BIGGEST_ALIGNMENT;
535 /* Allow the target to (possibly) increase the alignment of this
537 type = type_for_mode (mode, 0);
539 alignment = LOCAL_ALIGNMENT (type, alignment);
541 alignment /= BITS_PER_UNIT;
543 else if (align == -1)
545 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
546 size = CEIL_ROUND (size, alignment);
549 alignment = align / BITS_PER_UNIT;
551 #ifdef FRAME_GROWS_DOWNWARD
552 function->x_frame_offset -= size;
555 /* Ignore alignment we can't do with expected alignment of the boundary. */
556 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
557 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
559 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
560 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
562 /* Round frame offset to that alignment.
563 We must be careful here, since FRAME_OFFSET might be negative and
564 division with a negative dividend isn't as well defined as we might
565 like. So we instead assume that ALIGNMENT is a power of two and
566 use logical operations which are unambiguous. */
567 #ifdef FRAME_GROWS_DOWNWARD
568 function->x_frame_offset = FLOOR_ROUND (function->x_frame_offset, alignment);
570 function->x_frame_offset = CEIL_ROUND (function->x_frame_offset, alignment);
573 /* On a big-endian machine, if we are allocating more space than we will use,
574 use the least significant bytes of those that are allocated. */
575 if (BYTES_BIG_ENDIAN && mode != BLKmode)
576 bigend_correction = size - GET_MODE_SIZE (mode);
578 /* If we have already instantiated virtual registers, return the actual
579 address relative to the frame pointer. */
580 if (function == cfun && virtuals_instantiated)
581 addr = plus_constant (frame_pointer_rtx,
582 (frame_offset + bigend_correction
583 + STARTING_FRAME_OFFSET));
585 addr = plus_constant (virtual_stack_vars_rtx,
586 function->x_frame_offset + bigend_correction);
588 #ifndef FRAME_GROWS_DOWNWARD
589 function->x_frame_offset += size;
592 x = gen_rtx_MEM (mode, addr);
594 function->x_stack_slot_list
595 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
597 if (function != cfun)
603 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
606 assign_stack_local (mode, size, align)
607 enum machine_mode mode;
611 return assign_stack_local_1 (mode, size, align, cfun);
614 /* Allocate a temporary stack slot and record it for possible later
617 MODE is the machine mode to be given to the returned rtx.
619 SIZE is the size in units of the space required. We do no rounding here
620 since assign_stack_local will do any required rounding.
622 KEEP is 1 if this slot is to be retained after a call to
623 free_temp_slots. Automatic variables for a block are allocated
624 with this flag. KEEP is 2 if we allocate a longer term temporary,
625 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
626 if we are to allocate something at an inner level to be treated as
627 a variable in the block (e.g., a SAVE_EXPR).
629 TYPE is the type that will be used for the stack slot. */
632 assign_stack_temp_for_type (mode, size, keep, type)
633 enum machine_mode mode;
640 struct temp_slot *p, *best_p = 0;
642 /* If SIZE is -1 it means that somebody tried to allocate a temporary
643 of a variable size. */
647 /* If we know the alias set for the memory that will be used, use
648 it. If there's no TYPE, then we don't know anything about the
649 alias set for the memory. */
651 alias_set = get_alias_set (type);
655 align = GET_MODE_ALIGNMENT (mode);
657 align = BIGGEST_ALIGNMENT;
660 type = type_for_mode (mode, 0);
662 align = LOCAL_ALIGNMENT (type, align);
664 /* Try to find an available, already-allocated temporary of the proper
665 mode which meets the size and alignment requirements. Choose the
666 smallest one with the closest alignment. */
667 for (p = temp_slots; p; p = p->next)
668 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
670 && (!flag_strict_aliasing
671 || (alias_set && p->alias_set == alias_set))
672 && (best_p == 0 || best_p->size > p->size
673 || (best_p->size == p->size && best_p->align > p->align)))
675 if (p->align == align && p->size == size)
683 /* Make our best, if any, the one to use. */
686 /* If there are enough aligned bytes left over, make them into a new
687 temp_slot so that the extra bytes don't get wasted. Do this only
688 for BLKmode slots, so that we can be sure of the alignment. */
689 if (GET_MODE (best_p->slot) == BLKmode
690 /* We can't split slots if -fstrict-aliasing because the
691 information about the alias set for the new slot will be
693 && !flag_strict_aliasing)
695 int alignment = best_p->align / BITS_PER_UNIT;
696 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
698 if (best_p->size - rounded_size >= alignment)
700 p = (struct temp_slot *) oballoc (sizeof (struct temp_slot));
701 p->in_use = p->addr_taken = 0;
702 p->size = best_p->size - rounded_size;
703 p->base_offset = best_p->base_offset + rounded_size;
704 p->full_size = best_p->full_size - rounded_size;
705 p->slot = gen_rtx_MEM (BLKmode,
706 plus_constant (XEXP (best_p->slot, 0),
708 p->align = best_p->align;
711 p->next = temp_slots;
714 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
717 best_p->size = rounded_size;
718 best_p->full_size = rounded_size;
725 /* If we still didn't find one, make a new temporary. */
728 HOST_WIDE_INT frame_offset_old = frame_offset;
730 p = (struct temp_slot *) oballoc (sizeof (struct temp_slot));
732 /* We are passing an explicit alignment request to assign_stack_local.
733 One side effect of that is assign_stack_local will not round SIZE
734 to ensure the frame offset remains suitably aligned.
736 So for requests which depended on the rounding of SIZE, we go ahead
737 and round it now. We also make sure ALIGNMENT is at least
738 BIGGEST_ALIGNMENT. */
739 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
741 p->slot = assign_stack_local (mode,
743 ? CEIL_ROUND (size, align / BITS_PER_UNIT)
748 p->alias_set = alias_set;
750 /* The following slot size computation is necessary because we don't
751 know the actual size of the temporary slot until assign_stack_local
752 has performed all the frame alignment and size rounding for the
753 requested temporary. Note that extra space added for alignment
754 can be either above or below this stack slot depending on which
755 way the frame grows. We include the extra space if and only if it
756 is above this slot. */
757 #ifdef FRAME_GROWS_DOWNWARD
758 p->size = frame_offset_old - frame_offset;
763 /* Now define the fields used by combine_temp_slots. */
764 #ifdef FRAME_GROWS_DOWNWARD
765 p->base_offset = frame_offset;
766 p->full_size = frame_offset_old - frame_offset;
768 p->base_offset = frame_offset_old;
769 p->full_size = frame_offset - frame_offset_old;
772 p->next = temp_slots;
778 p->rtl_expr = seq_rtl_expr;
782 p->level = target_temp_slot_level;
787 p->level = var_temp_slot_level;
792 p->level = temp_slot_level;
796 /* We may be reusing an old slot, so clear any MEM flags that may have been
798 RTX_UNCHANGING_P (p->slot) = 0;
799 MEM_IN_STRUCT_P (p->slot) = 0;
800 MEM_SCALAR_P (p->slot) = 0;
801 MEM_ALIAS_SET (p->slot) = 0;
805 /* Allocate a temporary stack slot and record it for possible later
806 reuse. First three arguments are same as in preceding function. */
809 assign_stack_temp (mode, size, keep)
810 enum machine_mode mode;
814 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
817 /* Assign a temporary of given TYPE.
818 KEEP is as for assign_stack_temp.
819 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
820 it is 0 if a register is OK.
821 DONT_PROMOTE is 1 if we should not promote values in register
825 assign_temp (type, keep, memory_required, dont_promote)
829 int dont_promote ATTRIBUTE_UNUSED;
831 enum machine_mode mode = TYPE_MODE (type);
832 #ifndef PROMOTE_FOR_CALL_ONLY
833 int unsignedp = TREE_UNSIGNED (type);
836 if (mode == BLKmode || memory_required)
838 HOST_WIDE_INT size = int_size_in_bytes (type);
841 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
842 problems with allocating the stack space. */
846 /* Unfortunately, we don't yet know how to allocate variable-sized
847 temporaries. However, sometimes we have a fixed upper limit on
848 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
849 instead. This is the case for Chill variable-sized strings. */
850 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
851 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
852 && TREE_CODE (TYPE_ARRAY_MAX_SIZE (type)) == INTEGER_CST)
853 size = TREE_INT_CST_LOW (TYPE_ARRAY_MAX_SIZE (type));
855 tmp = assign_stack_temp_for_type (mode, size, keep, type);
856 MEM_SET_IN_STRUCT_P (tmp, AGGREGATE_TYPE_P (type));
860 #ifndef PROMOTE_FOR_CALL_ONLY
862 mode = promote_mode (type, mode, &unsignedp, 0);
865 return gen_reg_rtx (mode);
868 /* Combine temporary stack slots which are adjacent on the stack.
870 This allows for better use of already allocated stack space. This is only
871 done for BLKmode slots because we can be sure that we won't have alignment
872 problems in this case. */
875 combine_temp_slots ()
877 struct temp_slot *p, *q;
878 struct temp_slot *prev_p, *prev_q;
881 /* We can't combine slots, because the information about which slot
882 is in which alias set will be lost. */
883 if (flag_strict_aliasing)
886 /* If there are a lot of temp slots, don't do anything unless
887 high levels of optimizaton. */
888 if (! flag_expensive_optimizations)
889 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
890 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
893 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
897 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
898 for (q = p->next, prev_q = p; q; q = prev_q->next)
901 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
903 if (p->base_offset + p->full_size == q->base_offset)
905 /* Q comes after P; combine Q into P. */
907 p->full_size += q->full_size;
910 else if (q->base_offset + q->full_size == p->base_offset)
912 /* P comes after Q; combine P into Q. */
914 q->full_size += p->full_size;
919 /* Either delete Q or advance past it. */
921 prev_q->next = q->next;
925 /* Either delete P or advance past it. */
929 prev_p->next = p->next;
931 temp_slots = p->next;
938 /* Find the temp slot corresponding to the object at address X. */
940 static struct temp_slot *
941 find_temp_slot_from_address (x)
947 for (p = temp_slots; p; p = p->next)
952 else if (XEXP (p->slot, 0) == x
954 || (GET_CODE (x) == PLUS
955 && XEXP (x, 0) == virtual_stack_vars_rtx
956 && GET_CODE (XEXP (x, 1)) == CONST_INT
957 && INTVAL (XEXP (x, 1)) >= p->base_offset
958 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
961 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
962 for (next = p->address; next; next = XEXP (next, 1))
963 if (XEXP (next, 0) == x)
967 /* If we have a sum involving a register, see if it points to a temp
969 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == REG
970 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
972 else if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == REG
973 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
979 /* Indicate that NEW is an alternate way of referring to the temp slot
980 that previously was known by OLD. */
983 update_temp_slot_address (old, new)
988 if (rtx_equal_p (old, new))
991 p = find_temp_slot_from_address (old);
993 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
994 is a register, see if one operand of the PLUS is a temporary
995 location. If so, NEW points into it. Otherwise, if both OLD and
996 NEW are a PLUS and if there is a register in common between them.
997 If so, try a recursive call on those values. */
1000 if (GET_CODE (old) != PLUS)
1003 if (GET_CODE (new) == REG)
1005 update_temp_slot_address (XEXP (old, 0), new);
1006 update_temp_slot_address (XEXP (old, 1), new);
1009 else if (GET_CODE (new) != PLUS)
1012 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
1013 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
1014 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
1015 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
1016 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
1017 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
1018 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
1019 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
1024 /* Otherwise add an alias for the temp's address. */
1025 else if (p->address == 0)
1029 if (GET_CODE (p->address) != EXPR_LIST)
1030 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1032 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1036 /* If X could be a reference to a temporary slot, mark the fact that its
1037 address was taken. */
1040 mark_temp_addr_taken (x)
1043 struct temp_slot *p;
1048 /* If X is not in memory or is at a constant address, it cannot be in
1049 a temporary slot. */
1050 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1053 p = find_temp_slot_from_address (XEXP (x, 0));
1058 /* If X could be a reference to a temporary slot, mark that slot as
1059 belonging to the to one level higher than the current level. If X
1060 matched one of our slots, just mark that one. Otherwise, we can't
1061 easily predict which it is, so upgrade all of them. Kept slots
1062 need not be touched.
1064 This is called when an ({...}) construct occurs and a statement
1065 returns a value in memory. */
1068 preserve_temp_slots (x)
1071 struct temp_slot *p = 0;
1073 /* If there is no result, we still might have some objects whose address
1074 were taken, so we need to make sure they stay around. */
1077 for (p = temp_slots; p; p = p->next)
1078 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1084 /* If X is a register that is being used as a pointer, see if we have
1085 a temporary slot we know it points to. To be consistent with
1086 the code below, we really should preserve all non-kept slots
1087 if we can't find a match, but that seems to be much too costly. */
1088 if (GET_CODE (x) == REG && REGNO_POINTER_FLAG (REGNO (x)))
1089 p = find_temp_slot_from_address (x);
1091 /* If X is not in memory or is at a constant address, it cannot be in
1092 a temporary slot, but it can contain something whose address was
1094 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1096 for (p = temp_slots; p; p = p->next)
1097 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1103 /* First see if we can find a match. */
1105 p = find_temp_slot_from_address (XEXP (x, 0));
1109 /* Move everything at our level whose address was taken to our new
1110 level in case we used its address. */
1111 struct temp_slot *q;
1113 if (p->level == temp_slot_level)
1115 for (q = temp_slots; q; q = q->next)
1116 if (q != p && q->addr_taken && q->level == p->level)
1125 /* Otherwise, preserve all non-kept slots at this level. */
1126 for (p = temp_slots; p; p = p->next)
1127 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1131 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1132 with that RTL_EXPR, promote it into a temporary slot at the present
1133 level so it will not be freed when we free slots made in the
1137 preserve_rtl_expr_result (x)
1140 struct temp_slot *p;
1142 /* If X is not in memory or is at a constant address, it cannot be in
1143 a temporary slot. */
1144 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1147 /* If we can find a match, move it to our level unless it is already at
1149 p = find_temp_slot_from_address (XEXP (x, 0));
1152 p->level = MIN (p->level, temp_slot_level);
1159 /* Free all temporaries used so far. This is normally called at the end
1160 of generating code for a statement. Don't free any temporaries
1161 currently in use for an RTL_EXPR that hasn't yet been emitted.
1162 We could eventually do better than this since it can be reused while
1163 generating the same RTL_EXPR, but this is complex and probably not
1169 struct temp_slot *p;
1171 for (p = temp_slots; p; p = p->next)
1172 if (p->in_use && p->level == temp_slot_level && ! p->keep
1173 && p->rtl_expr == 0)
1176 combine_temp_slots ();
1179 /* Free all temporary slots used in T, an RTL_EXPR node. */
1182 free_temps_for_rtl_expr (t)
1185 struct temp_slot *p;
1187 for (p = temp_slots; p; p = p->next)
1188 if (p->rtl_expr == t)
1191 combine_temp_slots ();
1194 /* Mark all temporaries ever allocated in this function as not suitable
1195 for reuse until the current level is exited. */
1198 mark_all_temps_used ()
1200 struct temp_slot *p;
1202 for (p = temp_slots; p; p = p->next)
1204 p->in_use = p->keep = 1;
1205 p->level = MIN (p->level, temp_slot_level);
1209 /* Push deeper into the nesting level for stack temporaries. */
1217 /* Likewise, but save the new level as the place to allocate variables
1222 push_temp_slots_for_block ()
1226 var_temp_slot_level = temp_slot_level;
1229 /* Likewise, but save the new level as the place to allocate temporaries
1230 for TARGET_EXPRs. */
1233 push_temp_slots_for_target ()
1237 target_temp_slot_level = temp_slot_level;
1240 /* Set and get the value of target_temp_slot_level. The only
1241 permitted use of these functions is to save and restore this value. */
1244 get_target_temp_slot_level ()
1246 return target_temp_slot_level;
1250 set_target_temp_slot_level (level)
1253 target_temp_slot_level = level;
1257 /* Pop a temporary nesting level. All slots in use in the current level
1263 struct temp_slot *p;
1265 for (p = temp_slots; p; p = p->next)
1266 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1269 combine_temp_slots ();
1274 /* Initialize temporary slots. */
1279 /* We have not allocated any temporaries yet. */
1281 temp_slot_level = 0;
1282 var_temp_slot_level = 0;
1283 target_temp_slot_level = 0;
1286 /* Retroactively move an auto variable from a register to a stack slot.
1287 This is done when an address-reference to the variable is seen. */
1290 put_var_into_stack (decl)
1294 enum machine_mode promoted_mode, decl_mode;
1295 struct function *function = 0;
1297 int can_use_addressof;
1299 context = decl_function_context (decl);
1301 /* Get the current rtl used for this object and its original mode. */
1302 reg = TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl) : DECL_RTL (decl);
1304 /* No need to do anything if decl has no rtx yet
1305 since in that case caller is setting TREE_ADDRESSABLE
1306 and a stack slot will be assigned when the rtl is made. */
1310 /* Get the declared mode for this object. */
1311 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1312 : DECL_MODE (decl));
1313 /* Get the mode it's actually stored in. */
1314 promoted_mode = GET_MODE (reg);
1316 /* If this variable comes from an outer function,
1317 find that function's saved context. */
1318 if (context != current_function_decl && context != inline_function_decl)
1319 for (function = outer_function_chain; function; function = function->next)
1320 if (function->decl == context)
1323 /* If this is a variable-size object with a pseudo to address it,
1324 put that pseudo into the stack, if the var is nonlocal. */
1325 if (DECL_NONLOCAL (decl)
1326 && GET_CODE (reg) == MEM
1327 && GET_CODE (XEXP (reg, 0)) == REG
1328 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1330 reg = XEXP (reg, 0);
1331 decl_mode = promoted_mode = GET_MODE (reg);
1337 /* FIXME make it work for promoted modes too */
1338 && decl_mode == promoted_mode
1339 #ifdef NON_SAVING_SETJMP
1340 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1344 /* If we can't use ADDRESSOF, make sure we see through one we already
1346 if (! can_use_addressof && GET_CODE (reg) == MEM
1347 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1348 reg = XEXP (XEXP (reg, 0), 0);
1350 /* Now we should have a value that resides in one or more pseudo regs. */
1352 if (GET_CODE (reg) == REG)
1354 /* If this variable lives in the current function and we don't need
1355 to put things in the stack for the sake of setjmp, try to keep it
1356 in a register until we know we actually need the address. */
1357 if (can_use_addressof)
1358 gen_mem_addressof (reg, decl);
1360 put_reg_into_stack (function, reg, TREE_TYPE (decl),
1361 promoted_mode, decl_mode,
1362 TREE_SIDE_EFFECTS (decl), 0,
1363 TREE_USED (decl) || DECL_INITIAL (decl) != 0,
1366 else if (GET_CODE (reg) == CONCAT)
1368 /* A CONCAT contains two pseudos; put them both in the stack.
1369 We do it so they end up consecutive. */
1370 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1371 tree part_type = TREE_TYPE (TREE_TYPE (decl));
1372 #ifdef FRAME_GROWS_DOWNWARD
1373 /* Since part 0 should have a lower address, do it second. */
1374 put_reg_into_stack (function, XEXP (reg, 1), part_type, part_mode,
1375 part_mode, TREE_SIDE_EFFECTS (decl), 0,
1376 TREE_USED (decl) || DECL_INITIAL (decl) != 0,
1378 put_reg_into_stack (function, XEXP (reg, 0), part_type, part_mode,
1379 part_mode, TREE_SIDE_EFFECTS (decl), 0,
1380 TREE_USED (decl) || DECL_INITIAL (decl) != 0,
1383 put_reg_into_stack (function, XEXP (reg, 0), part_type, part_mode,
1384 part_mode, TREE_SIDE_EFFECTS (decl), 0,
1385 TREE_USED (decl) || DECL_INITIAL (decl) != 0,
1387 put_reg_into_stack (function, XEXP (reg, 1), part_type, part_mode,
1388 part_mode, TREE_SIDE_EFFECTS (decl), 0,
1389 TREE_USED (decl) || DECL_INITIAL (decl) != 0,
1393 /* Change the CONCAT into a combined MEM for both parts. */
1394 PUT_CODE (reg, MEM);
1395 MEM_VOLATILE_P (reg) = MEM_VOLATILE_P (XEXP (reg, 0));
1396 MEM_ALIAS_SET (reg) = get_alias_set (decl);
1398 /* The two parts are in memory order already.
1399 Use the lower parts address as ours. */
1400 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1401 /* Prevent sharing of rtl that might lose. */
1402 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1403 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1408 if (current_function_check_memory_usage)
1409 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
1410 XEXP (reg, 0), Pmode,
1411 GEN_INT (GET_MODE_SIZE (GET_MODE (reg))),
1412 TYPE_MODE (sizetype),
1413 GEN_INT (MEMORY_USE_RW),
1414 TYPE_MODE (integer_type_node));
1417 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1418 into the stack frame of FUNCTION (0 means the current function).
1419 DECL_MODE is the machine mode of the user-level data type.
1420 PROMOTED_MODE is the machine mode of the register.
1421 VOLATILE_P is nonzero if this is for a "volatile" decl.
1422 USED_P is nonzero if this reg might have already been used in an insn. */
1425 put_reg_into_stack (function, reg, type, promoted_mode, decl_mode, volatile_p,
1426 original_regno, used_p, ht)
1427 struct function *function;
1430 enum machine_mode promoted_mode, decl_mode;
1434 struct hash_table *ht;
1436 struct function *func = function ? function : cfun;
1438 int regno = original_regno;
1441 regno = REGNO (reg);
1443 if (regno < func->x_max_parm_reg)
1444 new = func->x_parm_reg_stack_loc[regno];
1446 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode), 0, func);
1448 PUT_CODE (reg, MEM);
1449 PUT_MODE (reg, decl_mode);
1450 XEXP (reg, 0) = XEXP (new, 0);
1451 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1452 MEM_VOLATILE_P (reg) = volatile_p;
1454 /* If this is a memory ref that contains aggregate components,
1455 mark it as such for cse and loop optimize. If we are reusing a
1456 previously generated stack slot, then we need to copy the bit in
1457 case it was set for other reasons. For instance, it is set for
1458 __builtin_va_alist. */
1459 MEM_SET_IN_STRUCT_P (reg,
1460 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1461 MEM_ALIAS_SET (reg) = get_alias_set (type);
1463 /* Now make sure that all refs to the variable, previously made
1464 when it was a register, are fixed up to be valid again. */
1466 if (used_p && function != 0)
1468 struct var_refs_queue *temp;
1471 = (struct var_refs_queue *) xmalloc (sizeof (struct var_refs_queue));
1472 temp->modified = reg;
1473 temp->promoted_mode = promoted_mode;
1474 temp->unsignedp = TREE_UNSIGNED (type);
1475 temp->next = function->fixup_var_refs_queue;
1476 function->fixup_var_refs_queue = temp;
1479 /* Variable is local; fix it up now. */
1480 fixup_var_refs (reg, promoted_mode, TREE_UNSIGNED (type), ht);
1484 fixup_var_refs (var, promoted_mode, unsignedp, ht)
1486 enum machine_mode promoted_mode;
1488 struct hash_table *ht;
1491 rtx first_insn = get_insns ();
1492 struct sequence_stack *stack = seq_stack;
1493 tree rtl_exps = rtl_expr_chain;
1495 /* Must scan all insns for stack-refs that exceed the limit. */
1496 fixup_var_refs_insns (var, promoted_mode, unsignedp, first_insn,
1498 /* If there's a hash table, it must record all uses of VAR. */
1502 /* Scan all pending sequences too. */
1503 for (; stack; stack = stack->next)
1505 push_to_sequence (stack->first);
1506 fixup_var_refs_insns (var, promoted_mode, unsignedp,
1507 stack->first, stack->next != 0, 0);
1508 /* Update remembered end of sequence
1509 in case we added an insn at the end. */
1510 stack->last = get_last_insn ();
1514 /* Scan all waiting RTL_EXPRs too. */
1515 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1517 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1518 if (seq != const0_rtx && seq != 0)
1520 push_to_sequence (seq);
1521 fixup_var_refs_insns (var, promoted_mode, unsignedp, seq, 0,
1527 /* Scan the catch clauses for exception handling too. */
1528 push_to_sequence (catch_clauses);
1529 fixup_var_refs_insns (var, promoted_mode, unsignedp, catch_clauses,
1534 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1535 some part of an insn. Return a struct fixup_replacement whose OLD
1536 value is equal to X. Allocate a new structure if no such entry exists. */
1538 static struct fixup_replacement *
1539 find_fixup_replacement (replacements, x)
1540 struct fixup_replacement **replacements;
1543 struct fixup_replacement *p;
1545 /* See if we have already replaced this. */
1546 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1551 p = (struct fixup_replacement *) oballoc (sizeof (struct fixup_replacement));
1554 p->next = *replacements;
1561 /* Scan the insn-chain starting with INSN for refs to VAR
1562 and fix them up. TOPLEVEL is nonzero if this chain is the
1563 main chain of insns for the current function. */
1566 fixup_var_refs_insns (var, promoted_mode, unsignedp, insn, toplevel, ht)
1568 enum machine_mode promoted_mode;
1572 struct hash_table *ht;
1575 rtx insn_list = NULL_RTX;
1577 /* If we already know which INSNs reference VAR there's no need
1578 to walk the entire instruction chain. */
1581 insn_list = ((struct insns_for_mem_entry *)
1582 hash_lookup (ht, var, /*create=*/0, /*copy=*/0))->insns;
1583 insn = insn_list ? XEXP (insn_list, 0) : NULL_RTX;
1584 insn_list = XEXP (insn_list, 1);
1589 rtx next = NEXT_INSN (insn);
1590 rtx set, prev, prev_set;
1593 if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
1595 /* Remember the notes in case we delete the insn. */
1596 note = REG_NOTES (insn);
1598 /* If this is a CLOBBER of VAR, delete it.
1600 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1601 and REG_RETVAL notes too. */
1602 if (GET_CODE (PATTERN (insn)) == CLOBBER
1603 && (XEXP (PATTERN (insn), 0) == var
1604 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1605 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1606 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1608 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1609 /* The REG_LIBCALL note will go away since we are going to
1610 turn INSN into a NOTE, so just delete the
1611 corresponding REG_RETVAL note. */
1612 remove_note (XEXP (note, 0),
1613 find_reg_note (XEXP (note, 0), REG_RETVAL,
1616 /* In unoptimized compilation, we shouldn't call delete_insn
1617 except in jump.c doing warnings. */
1618 PUT_CODE (insn, NOTE);
1619 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1620 NOTE_SOURCE_FILE (insn) = 0;
1623 /* The insn to load VAR from a home in the arglist
1624 is now a no-op. When we see it, just delete it.
1625 Similarly if this is storing VAR from a register from which
1626 it was loaded in the previous insn. This will occur
1627 when an ADDRESSOF was made for an arglist slot. */
1629 && (set = single_set (insn)) != 0
1630 && SET_DEST (set) == var
1631 /* If this represents the result of an insn group,
1632 don't delete the insn. */
1633 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1634 && (rtx_equal_p (SET_SRC (set), var)
1635 || (GET_CODE (SET_SRC (set)) == REG
1636 && (prev = prev_nonnote_insn (insn)) != 0
1637 && (prev_set = single_set (prev)) != 0
1638 && SET_DEST (prev_set) == SET_SRC (set)
1639 && rtx_equal_p (SET_SRC (prev_set), var))))
1641 /* In unoptimized compilation, we shouldn't call delete_insn
1642 except in jump.c doing warnings. */
1643 PUT_CODE (insn, NOTE);
1644 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1645 NOTE_SOURCE_FILE (insn) = 0;
1646 if (insn == last_parm_insn)
1647 last_parm_insn = PREV_INSN (next);
1651 struct fixup_replacement *replacements = 0;
1652 rtx next_insn = NEXT_INSN (insn);
1654 if (SMALL_REGISTER_CLASSES)
1656 /* If the insn that copies the results of a CALL_INSN
1657 into a pseudo now references VAR, we have to use an
1658 intermediate pseudo since we want the life of the
1659 return value register to be only a single insn.
1661 If we don't use an intermediate pseudo, such things as
1662 address computations to make the address of VAR valid
1663 if it is not can be placed between the CALL_INSN and INSN.
1665 To make sure this doesn't happen, we record the destination
1666 of the CALL_INSN and see if the next insn uses both that
1669 if (call_dest != 0 && GET_CODE (insn) == INSN
1670 && reg_mentioned_p (var, PATTERN (insn))
1671 && reg_mentioned_p (call_dest, PATTERN (insn)))
1673 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1675 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1677 PATTERN (insn) = replace_rtx (PATTERN (insn),
1681 if (GET_CODE (insn) == CALL_INSN
1682 && GET_CODE (PATTERN (insn)) == SET)
1683 call_dest = SET_DEST (PATTERN (insn));
1684 else if (GET_CODE (insn) == CALL_INSN
1685 && GET_CODE (PATTERN (insn)) == PARALLEL
1686 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1687 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1692 /* See if we have to do anything to INSN now that VAR is in
1693 memory. If it needs to be loaded into a pseudo, use a single
1694 pseudo for the entire insn in case there is a MATCH_DUP
1695 between two operands. We pass a pointer to the head of
1696 a list of struct fixup_replacements. If fixup_var_refs_1
1697 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1698 it will record them in this list.
1700 If it allocated a pseudo for any replacement, we copy into
1703 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1706 /* If this is last_parm_insn, and any instructions were output
1707 after it to fix it up, then we must set last_parm_insn to
1708 the last such instruction emitted. */
1709 if (insn == last_parm_insn)
1710 last_parm_insn = PREV_INSN (next_insn);
1712 while (replacements)
1714 if (GET_CODE (replacements->new) == REG)
1719 /* OLD might be a (subreg (mem)). */
1720 if (GET_CODE (replacements->old) == SUBREG)
1722 = fixup_memory_subreg (replacements->old, insn, 0);
1725 = fixup_stack_1 (replacements->old, insn);
1727 insert_before = insn;
1729 /* If we are changing the mode, do a conversion.
1730 This might be wasteful, but combine.c will
1731 eliminate much of the waste. */
1733 if (GET_MODE (replacements->new)
1734 != GET_MODE (replacements->old))
1737 convert_move (replacements->new,
1738 replacements->old, unsignedp);
1739 seq = gen_sequence ();
1743 seq = gen_move_insn (replacements->new,
1746 emit_insn_before (seq, insert_before);
1749 replacements = replacements->next;
1753 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1754 But don't touch other insns referred to by reg-notes;
1755 we will get them elsewhere. */
1758 if (GET_CODE (note) != INSN_LIST)
1760 = walk_fixup_memory_subreg (XEXP (note, 0), insn, 1);
1761 note = XEXP (note, 1);
1769 insn = XEXP (insn_list, 0);
1770 insn_list = XEXP (insn_list, 1);
1777 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1778 See if the rtx expression at *LOC in INSN needs to be changed.
1780 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1781 contain a list of original rtx's and replacements. If we find that we need
1782 to modify this insn by replacing a memory reference with a pseudo or by
1783 making a new MEM to implement a SUBREG, we consult that list to see if
1784 we have already chosen a replacement. If none has already been allocated,
1785 we allocate it and update the list. fixup_var_refs_insns will copy VAR
1786 or the SUBREG, as appropriate, to the pseudo. */
1789 fixup_var_refs_1 (var, promoted_mode, loc, insn, replacements)
1791 enum machine_mode promoted_mode;
1794 struct fixup_replacement **replacements;
1797 register rtx x = *loc;
1798 RTX_CODE code = GET_CODE (x);
1799 register const char *fmt;
1800 register rtx tem, tem1;
1801 struct fixup_replacement *replacement;
1806 if (XEXP (x, 0) == var)
1808 /* Prevent sharing of rtl that might lose. */
1809 rtx sub = copy_rtx (XEXP (var, 0));
1811 if (! validate_change (insn, loc, sub, 0))
1813 rtx y = gen_reg_rtx (GET_MODE (sub));
1816 /* We should be able to replace with a register or all is lost.
1817 Note that we can't use validate_change to verify this, since
1818 we're not caring for replacing all dups simultaneously. */
1819 if (! validate_replace_rtx (*loc, y, insn))
1822 /* Careful! First try to recognize a direct move of the
1823 value, mimicking how things are done in gen_reload wrt
1824 PLUS. Consider what happens when insn is a conditional
1825 move instruction and addsi3 clobbers flags. */
1828 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1829 seq = gen_sequence ();
1832 if (recog_memoized (new_insn) < 0)
1834 /* That failed. Fall back on force_operand and hope. */
1837 force_operand (sub, y);
1838 seq = gen_sequence ();
1843 /* Don't separate setter from user. */
1844 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1845 insn = PREV_INSN (insn);
1848 emit_insn_before (seq, insn);
1856 /* If we already have a replacement, use it. Otherwise,
1857 try to fix up this address in case it is invalid. */
1859 replacement = find_fixup_replacement (replacements, var);
1860 if (replacement->new)
1862 *loc = replacement->new;
1866 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1868 /* Unless we are forcing memory to register or we changed the mode,
1869 we can leave things the way they are if the insn is valid. */
1871 INSN_CODE (insn) = -1;
1872 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1873 && recog_memoized (insn) >= 0)
1876 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1880 /* If X contains VAR, we need to unshare it here so that we update
1881 each occurrence separately. But all identical MEMs in one insn
1882 must be replaced with the same rtx because of the possibility of
1885 if (reg_mentioned_p (var, x))
1887 replacement = find_fixup_replacement (replacements, x);
1888 if (replacement->new == 0)
1889 replacement->new = copy_most_rtx (x, var);
1891 *loc = x = replacement->new;
1907 /* Note that in some cases those types of expressions are altered
1908 by optimize_bit_field, and do not survive to get here. */
1909 if (XEXP (x, 0) == var
1910 || (GET_CODE (XEXP (x, 0)) == SUBREG
1911 && SUBREG_REG (XEXP (x, 0)) == var))
1913 /* Get TEM as a valid MEM in the mode presently in the insn.
1915 We don't worry about the possibility of MATCH_DUP here; it
1916 is highly unlikely and would be tricky to handle. */
1919 if (GET_CODE (tem) == SUBREG)
1921 if (GET_MODE_BITSIZE (GET_MODE (tem))
1922 > GET_MODE_BITSIZE (GET_MODE (var)))
1924 replacement = find_fixup_replacement (replacements, var);
1925 if (replacement->new == 0)
1926 replacement->new = gen_reg_rtx (GET_MODE (var));
1927 SUBREG_REG (tem) = replacement->new;
1930 tem = fixup_memory_subreg (tem, insn, 0);
1933 tem = fixup_stack_1 (tem, insn);
1935 /* Unless we want to load from memory, get TEM into the proper mode
1936 for an extract from memory. This can only be done if the
1937 extract is at a constant position and length. */
1939 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
1940 && GET_CODE (XEXP (x, 2)) == CONST_INT
1941 && ! mode_dependent_address_p (XEXP (tem, 0))
1942 && ! MEM_VOLATILE_P (tem))
1944 enum machine_mode wanted_mode = VOIDmode;
1945 enum machine_mode is_mode = GET_MODE (tem);
1946 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
1949 if (GET_CODE (x) == ZERO_EXTRACT)
1952 = insn_data[(int) CODE_FOR_extzv].operand[1].mode;
1953 if (wanted_mode == VOIDmode)
1954 wanted_mode = word_mode;
1958 if (GET_CODE (x) == SIGN_EXTRACT)
1960 wanted_mode = insn_data[(int) CODE_FOR_extv].operand[1].mode;
1961 if (wanted_mode == VOIDmode)
1962 wanted_mode = word_mode;
1965 /* If we have a narrower mode, we can do something. */
1966 if (wanted_mode != VOIDmode
1967 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
1969 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
1970 rtx old_pos = XEXP (x, 2);
1973 /* If the bytes and bits are counted differently, we
1974 must adjust the offset. */
1975 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
1976 offset = (GET_MODE_SIZE (is_mode)
1977 - GET_MODE_SIZE (wanted_mode) - offset);
1979 pos %= GET_MODE_BITSIZE (wanted_mode);
1981 newmem = gen_rtx_MEM (wanted_mode,
1982 plus_constant (XEXP (tem, 0), offset));
1983 RTX_UNCHANGING_P (newmem) = RTX_UNCHANGING_P (tem);
1984 MEM_COPY_ATTRIBUTES (newmem, tem);
1986 /* Make the change and see if the insn remains valid. */
1987 INSN_CODE (insn) = -1;
1988 XEXP (x, 0) = newmem;
1989 XEXP (x, 2) = GEN_INT (pos);
1991 if (recog_memoized (insn) >= 0)
1994 /* Otherwise, restore old position. XEXP (x, 0) will be
1996 XEXP (x, 2) = old_pos;
2000 /* If we get here, the bitfield extract insn can't accept a memory
2001 reference. Copy the input into a register. */
2003 tem1 = gen_reg_rtx (GET_MODE (tem));
2004 emit_insn_before (gen_move_insn (tem1, tem), insn);
2011 if (SUBREG_REG (x) == var)
2013 /* If this is a special SUBREG made because VAR was promoted
2014 from a wider mode, replace it with VAR and call ourself
2015 recursively, this time saying that the object previously
2016 had its current mode (by virtue of the SUBREG). */
2018 if (SUBREG_PROMOTED_VAR_P (x))
2021 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements);
2025 /* If this SUBREG makes VAR wider, it has become a paradoxical
2026 SUBREG with VAR in memory, but these aren't allowed at this
2027 stage of the compilation. So load VAR into a pseudo and take
2028 a SUBREG of that pseudo. */
2029 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2031 replacement = find_fixup_replacement (replacements, var);
2032 if (replacement->new == 0)
2033 replacement->new = gen_reg_rtx (GET_MODE (var));
2034 SUBREG_REG (x) = replacement->new;
2038 /* See if we have already found a replacement for this SUBREG.
2039 If so, use it. Otherwise, make a MEM and see if the insn
2040 is recognized. If not, or if we should force MEM into a register,
2041 make a pseudo for this SUBREG. */
2042 replacement = find_fixup_replacement (replacements, x);
2043 if (replacement->new)
2045 *loc = replacement->new;
2049 replacement->new = *loc = fixup_memory_subreg (x, insn, 0);
2051 INSN_CODE (insn) = -1;
2052 if (! flag_force_mem && recog_memoized (insn) >= 0)
2055 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2061 /* First do special simplification of bit-field references. */
2062 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2063 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2064 optimize_bit_field (x, insn, 0);
2065 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2066 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2067 optimize_bit_field (x, insn, NULL_PTR);
2069 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2070 into a register and then store it back out. */
2071 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2072 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2073 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2074 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2075 > GET_MODE_SIZE (GET_MODE (var))))
2077 replacement = find_fixup_replacement (replacements, var);
2078 if (replacement->new == 0)
2079 replacement->new = gen_reg_rtx (GET_MODE (var));
2081 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2082 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2085 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2086 insn into a pseudo and store the low part of the pseudo into VAR. */
2087 if (GET_CODE (SET_DEST (x)) == SUBREG
2088 && SUBREG_REG (SET_DEST (x)) == var
2089 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2090 > GET_MODE_SIZE (GET_MODE (var))))
2092 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2093 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2100 rtx dest = SET_DEST (x);
2101 rtx src = SET_SRC (x);
2103 rtx outerdest = dest;
2106 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2107 || GET_CODE (dest) == SIGN_EXTRACT
2108 || GET_CODE (dest) == ZERO_EXTRACT)
2109 dest = XEXP (dest, 0);
2111 if (GET_CODE (src) == SUBREG)
2112 src = XEXP (src, 0);
2114 /* If VAR does not appear at the top level of the SET
2115 just scan the lower levels of the tree. */
2117 if (src != var && dest != var)
2120 /* We will need to rerecognize this insn. */
2121 INSN_CODE (insn) = -1;
2124 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var)
2126 /* Since this case will return, ensure we fixup all the
2128 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2129 insn, replacements);
2130 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2131 insn, replacements);
2132 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2133 insn, replacements);
2135 tem = XEXP (outerdest, 0);
2137 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2138 that may appear inside a ZERO_EXTRACT.
2139 This was legitimate when the MEM was a REG. */
2140 if (GET_CODE (tem) == SUBREG
2141 && SUBREG_REG (tem) == var)
2142 tem = fixup_memory_subreg (tem, insn, 0);
2144 tem = fixup_stack_1 (tem, insn);
2146 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2147 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2148 && ! mode_dependent_address_p (XEXP (tem, 0))
2149 && ! MEM_VOLATILE_P (tem))
2151 enum machine_mode wanted_mode;
2152 enum machine_mode is_mode = GET_MODE (tem);
2153 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2155 wanted_mode = insn_data[(int) CODE_FOR_insv].operand[0].mode;
2156 if (wanted_mode == VOIDmode)
2157 wanted_mode = word_mode;
2159 /* If we have a narrower mode, we can do something. */
2160 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2162 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2163 rtx old_pos = XEXP (outerdest, 2);
2166 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2167 offset = (GET_MODE_SIZE (is_mode)
2168 - GET_MODE_SIZE (wanted_mode) - offset);
2170 pos %= GET_MODE_BITSIZE (wanted_mode);
2172 newmem = gen_rtx_MEM (wanted_mode,
2173 plus_constant (XEXP (tem, 0),
2175 RTX_UNCHANGING_P (newmem) = RTX_UNCHANGING_P (tem);
2176 MEM_COPY_ATTRIBUTES (newmem, tem);
2178 /* Make the change and see if the insn remains valid. */
2179 INSN_CODE (insn) = -1;
2180 XEXP (outerdest, 0) = newmem;
2181 XEXP (outerdest, 2) = GEN_INT (pos);
2183 if (recog_memoized (insn) >= 0)
2186 /* Otherwise, restore old position. XEXP (x, 0) will be
2188 XEXP (outerdest, 2) = old_pos;
2192 /* If we get here, the bit-field store doesn't allow memory
2193 or isn't located at a constant position. Load the value into
2194 a register, do the store, and put it back into memory. */
2196 tem1 = gen_reg_rtx (GET_MODE (tem));
2197 emit_insn_before (gen_move_insn (tem1, tem), insn);
2198 emit_insn_after (gen_move_insn (tem, tem1), insn);
2199 XEXP (outerdest, 0) = tem1;
2204 /* STRICT_LOW_PART is a no-op on memory references
2205 and it can cause combinations to be unrecognizable,
2208 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2209 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2211 /* A valid insn to copy VAR into or out of a register
2212 must be left alone, to avoid an infinite loop here.
2213 If the reference to VAR is by a subreg, fix that up,
2214 since SUBREG is not valid for a memref.
2215 Also fix up the address of the stack slot.
2217 Note that we must not try to recognize the insn until
2218 after we know that we have valid addresses and no
2219 (subreg (mem ...) ...) constructs, since these interfere
2220 with determining the validity of the insn. */
2222 if ((SET_SRC (x) == var
2223 || (GET_CODE (SET_SRC (x)) == SUBREG
2224 && SUBREG_REG (SET_SRC (x)) == var))
2225 && (GET_CODE (SET_DEST (x)) == REG
2226 || (GET_CODE (SET_DEST (x)) == SUBREG
2227 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2228 && GET_MODE (var) == promoted_mode
2229 && x == single_set (insn))
2233 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2234 if (replacement->new)
2235 SET_SRC (x) = replacement->new;
2236 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2237 SET_SRC (x) = replacement->new
2238 = fixup_memory_subreg (SET_SRC (x), insn, 0);
2240 SET_SRC (x) = replacement->new
2241 = fixup_stack_1 (SET_SRC (x), insn);
2243 if (recog_memoized (insn) >= 0)
2246 /* INSN is not valid, but we know that we want to
2247 copy SET_SRC (x) to SET_DEST (x) in some way. So
2248 we generate the move and see whether it requires more
2249 than one insn. If it does, we emit those insns and
2250 delete INSN. Otherwise, we an just replace the pattern
2251 of INSN; we have already verified above that INSN has
2252 no other function that to do X. */
2254 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2255 if (GET_CODE (pat) == SEQUENCE)
2257 emit_insn_after (pat, insn);
2258 PUT_CODE (insn, NOTE);
2259 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
2260 NOTE_SOURCE_FILE (insn) = 0;
2263 PATTERN (insn) = pat;
2268 if ((SET_DEST (x) == var
2269 || (GET_CODE (SET_DEST (x)) == SUBREG
2270 && SUBREG_REG (SET_DEST (x)) == var))
2271 && (GET_CODE (SET_SRC (x)) == REG
2272 || (GET_CODE (SET_SRC (x)) == SUBREG
2273 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2274 && GET_MODE (var) == promoted_mode
2275 && x == single_set (insn))
2279 if (GET_CODE (SET_DEST (x)) == SUBREG)
2280 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn, 0);
2282 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2284 if (recog_memoized (insn) >= 0)
2287 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2288 if (GET_CODE (pat) == SEQUENCE)
2290 emit_insn_after (pat, insn);
2291 PUT_CODE (insn, NOTE);
2292 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
2293 NOTE_SOURCE_FILE (insn) = 0;
2296 PATTERN (insn) = pat;
2301 /* Otherwise, storing into VAR must be handled specially
2302 by storing into a temporary and copying that into VAR
2303 with a new insn after this one. Note that this case
2304 will be used when storing into a promoted scalar since
2305 the insn will now have different modes on the input
2306 and output and hence will be invalid (except for the case
2307 of setting it to a constant, which does not need any
2308 change if it is valid). We generate extra code in that case,
2309 but combine.c will eliminate it. */
2314 rtx fixeddest = SET_DEST (x);
2316 /* STRICT_LOW_PART can be discarded, around a MEM. */
2317 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2318 fixeddest = XEXP (fixeddest, 0);
2319 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2320 if (GET_CODE (fixeddest) == SUBREG)
2322 fixeddest = fixup_memory_subreg (fixeddest, insn, 0);
2323 promoted_mode = GET_MODE (fixeddest);
2326 fixeddest = fixup_stack_1 (fixeddest, insn);
2328 temp = gen_reg_rtx (promoted_mode);
2330 emit_insn_after (gen_move_insn (fixeddest,
2331 gen_lowpart (GET_MODE (fixeddest),
2335 SET_DEST (x) = temp;
2343 /* Nothing special about this RTX; fix its operands. */
2345 fmt = GET_RTX_FORMAT (code);
2346 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2349 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements);
2350 else if (fmt[i] == 'E')
2353 for (j = 0; j < XVECLEN (x, i); j++)
2354 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2355 insn, replacements);
2360 /* Given X, an rtx of the form (SUBREG:m1 (MEM:m2 addr)),
2361 return an rtx (MEM:m1 newaddr) which is equivalent.
2362 If any insns must be emitted to compute NEWADDR, put them before INSN.
2364 UNCRITICAL nonzero means accept paradoxical subregs.
2365 This is used for subregs found inside REG_NOTES. */
2368 fixup_memory_subreg (x, insn, uncritical)
2373 int offset = SUBREG_WORD (x) * UNITS_PER_WORD;
2374 rtx addr = XEXP (SUBREG_REG (x), 0);
2375 enum machine_mode mode = GET_MODE (x);
2378 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2379 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))
2383 if (BYTES_BIG_ENDIAN)
2384 offset += (MIN (UNITS_PER_WORD, GET_MODE_SIZE (GET_MODE (SUBREG_REG (x))))
2385 - MIN (UNITS_PER_WORD, GET_MODE_SIZE (mode)));
2386 addr = plus_constant (addr, offset);
2387 if (!flag_force_addr && memory_address_p (mode, addr))
2388 /* Shortcut if no insns need be emitted. */
2389 return change_address (SUBREG_REG (x), mode, addr);
2391 result = change_address (SUBREG_REG (x), mode, addr);
2392 emit_insn_before (gen_sequence (), insn);
2397 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2398 Replace subexpressions of X in place.
2399 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2400 Otherwise return X, with its contents possibly altered.
2402 If any insns must be emitted to compute NEWADDR, put them before INSN.
2404 UNCRITICAL is as in fixup_memory_subreg. */
2407 walk_fixup_memory_subreg (x, insn, uncritical)
2412 register enum rtx_code code;
2413 register const char *fmt;
2419 code = GET_CODE (x);
2421 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2422 return fixup_memory_subreg (x, insn, uncritical);
2424 /* Nothing special about this RTX; fix its operands. */
2426 fmt = GET_RTX_FORMAT (code);
2427 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2430 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn, uncritical);
2431 else if (fmt[i] == 'E')
2434 for (j = 0; j < XVECLEN (x, i); j++)
2436 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn, uncritical);
2442 /* For each memory ref within X, if it refers to a stack slot
2443 with an out of range displacement, put the address in a temp register
2444 (emitting new insns before INSN to load these registers)
2445 and alter the memory ref to use that register.
2446 Replace each such MEM rtx with a copy, to avoid clobberage. */
2449 fixup_stack_1 (x, insn)
2454 register RTX_CODE code = GET_CODE (x);
2455 register const char *fmt;
2459 register rtx ad = XEXP (x, 0);
2460 /* If we have address of a stack slot but it's not valid
2461 (displacement is too large), compute the sum in a register. */
2462 if (GET_CODE (ad) == PLUS
2463 && GET_CODE (XEXP (ad, 0)) == REG
2464 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2465 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2466 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2467 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2468 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2470 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2471 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2472 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2473 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2476 if (memory_address_p (GET_MODE (x), ad))
2480 temp = copy_to_reg (ad);
2481 seq = gen_sequence ();
2483 emit_insn_before (seq, insn);
2484 return change_address (x, VOIDmode, temp);
2489 fmt = GET_RTX_FORMAT (code);
2490 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2493 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2494 else if (fmt[i] == 'E')
2497 for (j = 0; j < XVECLEN (x, i); j++)
2498 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2504 /* Optimization: a bit-field instruction whose field
2505 happens to be a byte or halfword in memory
2506 can be changed to a move instruction.
2508 We call here when INSN is an insn to examine or store into a bit-field.
2509 BODY is the SET-rtx to be altered.
2511 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2512 (Currently this is called only from function.c, and EQUIV_MEM
2516 optimize_bit_field (body, insn, equiv_mem)
2521 register rtx bitfield;
2524 enum machine_mode mode;
2526 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2527 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2528 bitfield = SET_DEST (body), destflag = 1;
2530 bitfield = SET_SRC (body), destflag = 0;
2532 /* First check that the field being stored has constant size and position
2533 and is in fact a byte or halfword suitably aligned. */
2535 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2536 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2537 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2539 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2541 register rtx memref = 0;
2543 /* Now check that the containing word is memory, not a register,
2544 and that it is safe to change the machine mode. */
2546 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2547 memref = XEXP (bitfield, 0);
2548 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2550 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2551 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2552 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2553 memref = SUBREG_REG (XEXP (bitfield, 0));
2554 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2556 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2557 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2560 && ! mode_dependent_address_p (XEXP (memref, 0))
2561 && ! MEM_VOLATILE_P (memref))
2563 /* Now adjust the address, first for any subreg'ing
2564 that we are now getting rid of,
2565 and then for which byte of the word is wanted. */
2567 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2570 /* Adjust OFFSET to count bits from low-address byte. */
2571 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2572 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2573 - offset - INTVAL (XEXP (bitfield, 1)));
2575 /* Adjust OFFSET to count bytes from low-address byte. */
2576 offset /= BITS_PER_UNIT;
2577 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2579 offset += SUBREG_WORD (XEXP (bitfield, 0)) * UNITS_PER_WORD;
2580 if (BYTES_BIG_ENDIAN)
2581 offset -= (MIN (UNITS_PER_WORD,
2582 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2583 - MIN (UNITS_PER_WORD,
2584 GET_MODE_SIZE (GET_MODE (memref))));
2588 memref = change_address (memref, mode,
2589 plus_constant (XEXP (memref, 0), offset));
2590 insns = get_insns ();
2592 emit_insns_before (insns, insn);
2594 /* Store this memory reference where
2595 we found the bit field reference. */
2599 validate_change (insn, &SET_DEST (body), memref, 1);
2600 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2602 rtx src = SET_SRC (body);
2603 while (GET_CODE (src) == SUBREG
2604 && SUBREG_WORD (src) == 0)
2605 src = SUBREG_REG (src);
2606 if (GET_MODE (src) != GET_MODE (memref))
2607 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2608 validate_change (insn, &SET_SRC (body), src, 1);
2610 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2611 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2612 /* This shouldn't happen because anything that didn't have
2613 one of these modes should have got converted explicitly
2614 and then referenced through a subreg.
2615 This is so because the original bit-field was
2616 handled by agg_mode and so its tree structure had
2617 the same mode that memref now has. */
2622 rtx dest = SET_DEST (body);
2624 while (GET_CODE (dest) == SUBREG
2625 && SUBREG_WORD (dest) == 0
2626 && (GET_MODE_CLASS (GET_MODE (dest))
2627 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2628 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2630 dest = SUBREG_REG (dest);
2632 validate_change (insn, &SET_DEST (body), dest, 1);
2634 if (GET_MODE (dest) == GET_MODE (memref))
2635 validate_change (insn, &SET_SRC (body), memref, 1);
2638 /* Convert the mem ref to the destination mode. */
2639 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2642 convert_move (newreg, memref,
2643 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2647 validate_change (insn, &SET_SRC (body), newreg, 1);
2651 /* See if we can convert this extraction or insertion into
2652 a simple move insn. We might not be able to do so if this
2653 was, for example, part of a PARALLEL.
2655 If we succeed, write out any needed conversions. If we fail,
2656 it is hard to guess why we failed, so don't do anything
2657 special; just let the optimization be suppressed. */
2659 if (apply_change_group () && seq)
2660 emit_insns_before (seq, insn);
2665 /* These routines are responsible for converting virtual register references
2666 to the actual hard register references once RTL generation is complete.
2668 The following four variables are used for communication between the
2669 routines. They contain the offsets of the virtual registers from their
2670 respective hard registers. */
2672 static int in_arg_offset;
2673 static int var_offset;
2674 static int dynamic_offset;
2675 static int out_arg_offset;
2676 static int cfa_offset;
2678 /* In most machines, the stack pointer register is equivalent to the bottom
2681 #ifndef STACK_POINTER_OFFSET
2682 #define STACK_POINTER_OFFSET 0
2685 /* If not defined, pick an appropriate default for the offset of dynamically
2686 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2687 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2689 #ifndef STACK_DYNAMIC_OFFSET
2691 #ifdef ACCUMULATE_OUTGOING_ARGS
2692 /* The bottom of the stack points to the actual arguments. If
2693 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2694 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2695 stack space for register parameters is not pushed by the caller, but
2696 rather part of the fixed stack areas and hence not included in
2697 `current_function_outgoing_args_size'. Nevertheless, we must allow
2698 for it when allocating stack dynamic objects. */
2700 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2701 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2702 (current_function_outgoing_args_size \
2703 + REG_PARM_STACK_SPACE (FNDECL) + (STACK_POINTER_OFFSET))
2706 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2707 (current_function_outgoing_args_size + (STACK_POINTER_OFFSET))
2711 #define STACK_DYNAMIC_OFFSET(FNDECL) STACK_POINTER_OFFSET
2715 /* On a few machines, the CFA coincides with the arg pointer. */
2717 #ifndef ARG_POINTER_CFA_OFFSET
2718 #define ARG_POINTER_CFA_OFFSET 0
2722 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just had
2723 its address taken. DECL is the decl for the object stored in the
2724 register, for later use if we do need to force REG into the stack.
2725 REG is overwritten by the MEM like in put_reg_into_stack. */
2728 gen_mem_addressof (reg, decl)
2732 tree type = TREE_TYPE (decl);
2733 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2736 /* If the original REG was a user-variable, then so is the REG whose
2737 address is being taken. Likewise for unchanging. */
2738 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2739 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2741 PUT_CODE (reg, MEM);
2742 PUT_MODE (reg, DECL_MODE (decl));
2744 MEM_VOLATILE_P (reg) = TREE_SIDE_EFFECTS (decl);
2745 MEM_SET_IN_STRUCT_P (reg, AGGREGATE_TYPE_P (type));
2746 MEM_ALIAS_SET (reg) = get_alias_set (decl);
2748 if (TREE_USED (decl) || DECL_INITIAL (decl) != 0)
2749 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), 0);
2754 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2758 flush_addressof (decl)
2761 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2762 && DECL_RTL (decl) != 0
2763 && GET_CODE (DECL_RTL (decl)) == MEM
2764 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2765 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2766 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2770 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2773 put_addressof_into_stack (r, ht)
2775 struct hash_table *ht;
2777 tree decl = ADDRESSOF_DECL (r);
2778 rtx reg = XEXP (r, 0);
2780 if (GET_CODE (reg) != REG)
2783 put_reg_into_stack (0, reg, TREE_TYPE (decl), GET_MODE (reg),
2784 DECL_MODE (decl), TREE_SIDE_EFFECTS (decl),
2785 ADDRESSOF_REGNO (r),
2786 TREE_USED (decl) || DECL_INITIAL (decl) != 0, ht);
2789 /* List of replacements made below in purge_addressof_1 when creating
2790 bitfield insertions. */
2791 static rtx purge_bitfield_addressof_replacements;
2793 /* List of replacements made below in purge_addressof_1 for patterns
2794 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2795 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2796 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2797 enough in complex cases, e.g. when some field values can be
2798 extracted by usage MEM with narrower mode. */
2799 static rtx purge_addressof_replacements;
2801 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2802 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2803 the stack. If the function returns FALSE then the replacement could not
2807 purge_addressof_1 (loc, insn, force, store, ht)
2811 struct hash_table *ht;
2817 boolean result = true;
2819 /* Re-start here to avoid recursion in common cases. */
2826 code = GET_CODE (x);
2828 /* If we don't return in any of the cases below, we will recurse inside
2829 the RTX, which will normally result in any ADDRESSOF being forced into
2833 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1, ht);
2834 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0, ht);
2838 else if (code == ADDRESSOF && GET_CODE (XEXP (x, 0)) == MEM)
2840 /* We must create a copy of the rtx because it was created by
2841 overwriting a REG rtx which is always shared. */
2842 rtx sub = copy_rtx (XEXP (XEXP (x, 0), 0));
2845 if (validate_change (insn, loc, sub, 0)
2846 || validate_replace_rtx (x, sub, insn))
2850 sub = force_operand (sub, NULL_RTX);
2851 if (! validate_change (insn, loc, sub, 0)
2852 && ! validate_replace_rtx (x, sub, insn))
2855 insns = gen_sequence ();
2857 emit_insn_before (insns, insn);
2861 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
2863 rtx sub = XEXP (XEXP (x, 0), 0);
2866 if (GET_CODE (sub) == MEM)
2868 sub2 = gen_rtx_MEM (GET_MODE (x), copy_rtx (XEXP (sub, 0)));
2869 MEM_COPY_ATTRIBUTES (sub2, sub);
2870 RTX_UNCHANGING_P (sub2) = RTX_UNCHANGING_P (sub);
2873 else if (GET_CODE (sub) == REG
2874 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
2876 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
2878 int size_x, size_sub;
2882 /* When processing REG_NOTES look at the list of
2883 replacements done on the insn to find the register that X
2887 for (tem = purge_bitfield_addressof_replacements;
2889 tem = XEXP (XEXP (tem, 1), 1))
2890 if (rtx_equal_p (x, XEXP (tem, 0)))
2892 *loc = XEXP (XEXP (tem, 1), 0);
2896 /* See comment for purge_addressof_replacements. */
2897 for (tem = purge_addressof_replacements;
2899 tem = XEXP (XEXP (tem, 1), 1))
2900 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
2902 rtx z = XEXP (XEXP (tem, 1), 0);
2904 if (GET_MODE (x) == GET_MODE (z)
2905 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
2906 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
2909 /* It can happen that the note may speak of things
2910 in a wider (or just different) mode than the
2911 code did. This is especially true of
2914 if (GET_CODE (z) == SUBREG && SUBREG_WORD (z) == 0)
2917 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
2918 && (GET_MODE_SIZE (GET_MODE (x))
2919 > GET_MODE_SIZE (GET_MODE (z))))
2921 /* This can occur as a result in invalid
2922 pointer casts, e.g. float f; ...
2923 *(long long int *)&f.
2924 ??? We could emit a warning here, but
2925 without a line number that wouldn't be
2927 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
2930 z = gen_lowpart (GET_MODE (x), z);
2936 /* Sometimes we may not be able to find the replacement. For
2937 example when the original insn was a MEM in a wider mode,
2938 and the note is part of a sign extension of a narrowed
2939 version of that MEM. Gcc testcase compile/990829-1.c can
2940 generate an example of this siutation. Rather than complain
2941 we return false, which will prompt our caller to remove the
2946 size_x = GET_MODE_BITSIZE (GET_MODE (x));
2947 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
2949 /* Don't even consider working with paradoxical subregs,
2950 or the moral equivalent seen here. */
2951 if (size_x <= size_sub
2952 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
2954 /* Do a bitfield insertion to mirror what would happen
2961 rtx p = PREV_INSN (insn);
2964 val = gen_reg_rtx (GET_MODE (x));
2965 if (! validate_change (insn, loc, val, 0))
2967 /* Discard the current sequence and put the
2968 ADDRESSOF on stack. */
2972 seq = gen_sequence ();
2974 emit_insn_before (seq, insn);
2975 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
2979 store_bit_field (sub, size_x, 0, GET_MODE (x),
2980 val, GET_MODE_SIZE (GET_MODE (sub)),
2981 GET_MODE_SIZE (GET_MODE (sub)));
2983 /* Make sure to unshare any shared rtl that store_bit_field
2984 might have created. */
2985 unshare_all_rtl_again (get_insns ());
2987 seq = gen_sequence ();
2989 p = emit_insn_after (seq, insn);
2990 if (NEXT_INSN (insn))
2991 compute_insns_for_mem (NEXT_INSN (insn),
2992 p ? NEXT_INSN (p) : NULL_RTX,
2997 rtx p = PREV_INSN (insn);
3000 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3001 GET_MODE (x), GET_MODE (x),
3002 GET_MODE_SIZE (GET_MODE (sub)),
3003 GET_MODE_SIZE (GET_MODE (sub)));
3005 if (! validate_change (insn, loc, val, 0))
3007 /* Discard the current sequence and put the
3008 ADDRESSOF on stack. */
3013 seq = gen_sequence ();
3015 emit_insn_before (seq, insn);
3016 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3020 /* Remember the replacement so that the same one can be done
3021 on the REG_NOTES. */
3022 purge_bitfield_addressof_replacements
3023 = gen_rtx_EXPR_LIST (VOIDmode, x,
3026 purge_bitfield_addressof_replacements));
3028 /* We replaced with a reg -- all done. */
3033 else if (validate_change (insn, loc, sub, 0))
3035 /* Remember the replacement so that the same one can be done
3036 on the REG_NOTES. */
3037 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3041 for (tem = purge_addressof_replacements;
3043 tem = XEXP (XEXP (tem, 1), 1))
3044 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3046 XEXP (XEXP (tem, 1), 0) = sub;
3049 purge_addressof_replacements
3050 = gen_rtx (EXPR_LIST, VOIDmode, XEXP (x, 0),
3051 gen_rtx_EXPR_LIST (VOIDmode, sub,
3052 purge_addressof_replacements));
3058 /* else give up and put it into the stack */
3061 else if (code == ADDRESSOF)
3063 put_addressof_into_stack (x, ht);
3066 else if (code == SET)
3068 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1, ht);
3069 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0, ht);
3073 /* Scan all subexpressions. */
3074 fmt = GET_RTX_FORMAT (code);
3075 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3078 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0, ht);
3079 else if (*fmt == 'E')
3080 for (j = 0; j < XVECLEN (x, i); j++)
3081 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0, ht);
3087 /* Return a new hash table entry in HT. */
3089 static struct hash_entry *
3090 insns_for_mem_newfunc (he, ht, k)
3091 struct hash_entry *he;
3092 struct hash_table *ht;
3093 hash_table_key k ATTRIBUTE_UNUSED;
3095 struct insns_for_mem_entry *ifmhe;
3099 ifmhe = ((struct insns_for_mem_entry *)
3100 hash_allocate (ht, sizeof (struct insns_for_mem_entry)));
3101 ifmhe->insns = NULL_RTX;
3106 /* Return a hash value for K, a REG. */
3108 static unsigned long
3109 insns_for_mem_hash (k)
3112 /* K is really a RTX. Just use the address as the hash value. */
3113 return (unsigned long) k;
3116 /* Return non-zero if K1 and K2 (two REGs) are the same. */
3119 insns_for_mem_comp (k1, k2)
3126 struct insns_for_mem_walk_info {
3127 /* The hash table that we are using to record which INSNs use which
3129 struct hash_table *ht;
3131 /* The INSN we are currently proessing. */
3134 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3135 to find the insns that use the REGs in the ADDRESSOFs. */
3139 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3140 that might be used in an ADDRESSOF expression, record this INSN in
3141 the hash table given by DATA (which is really a pointer to an
3142 insns_for_mem_walk_info structure). */
3145 insns_for_mem_walk (r, data)
3149 struct insns_for_mem_walk_info *ifmwi
3150 = (struct insns_for_mem_walk_info *) data;
3152 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3153 && GET_CODE (XEXP (*r, 0)) == REG)
3154 hash_lookup (ifmwi->ht, XEXP (*r, 0), /*create=*/1, /*copy=*/0);
3155 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3157 /* Lookup this MEM in the hashtable, creating it if necessary. */
3158 struct insns_for_mem_entry *ifme
3159 = (struct insns_for_mem_entry *) hash_lookup (ifmwi->ht,
3164 /* If we have not already recorded this INSN, do so now. Since
3165 we process the INSNs in order, we know that if we have
3166 recorded it it must be at the front of the list. */
3167 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3169 /* We do the allocation on the same obstack as is used for
3170 the hash table since this memory will not be used once
3171 the hash table is deallocated. */
3172 push_obstacks (&ifmwi->ht->memory, &ifmwi->ht->memory);
3173 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3182 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3183 which REGs in HT. */
3186 compute_insns_for_mem (insns, last_insn, ht)
3189 struct hash_table *ht;
3192 struct insns_for_mem_walk_info ifmwi;
3195 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3196 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3197 if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
3200 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3204 /* Helper function for purge_addressof called through for_each_rtx.
3205 Returns true iff the rtl is an ADDRESSOF. */
3207 is_addressof (rtl, data)
3209 void * data ATTRIBUTE_UNUSED;
3211 return GET_CODE (* rtl) == ADDRESSOF;
3214 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3215 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3219 purge_addressof (insns)
3223 struct hash_table ht;
3225 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3226 requires a fixup pass over the instruction stream to correct
3227 INSNs that depended on the REG being a REG, and not a MEM. But,
3228 these fixup passes are slow. Furthermore, more MEMs are not
3229 mentioned in very many instructions. So, we speed up the process
3230 by pre-calculating which REGs occur in which INSNs; that allows
3231 us to perform the fixup passes much more quickly. */
3232 hash_table_init (&ht,
3233 insns_for_mem_newfunc,
3235 insns_for_mem_comp);
3236 compute_insns_for_mem (insns, NULL_RTX, &ht);
3238 for (insn = insns; insn; insn = NEXT_INSN (insn))
3239 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3240 || GET_CODE (insn) == CALL_INSN)
3242 if (! purge_addressof_1 (&PATTERN (insn), insn,
3243 asm_noperands (PATTERN (insn)) > 0, 0, &ht))
3244 /* If we could not replace the ADDRESSOFs in the insn,
3245 something is wrong. */
3248 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, &ht))
3250 /* If we could not replace the ADDRESSOFs in the insn's notes,
3251 we can just remove the offending notes instead. */
3254 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3256 /* If we find a REG_RETVAL note then the insn is a libcall.
3257 Such insns must have REG_EQUAL notes as well, in order
3258 for later passes of the compiler to work. So it is not
3259 safe to delete the notes here, and instead we abort. */
3260 if (REG_NOTE_KIND (note) == REG_RETVAL)
3262 if (for_each_rtx (& note, is_addressof, NULL))
3263 remove_note (insn, note);
3269 hash_table_free (&ht);
3270 purge_bitfield_addressof_replacements = 0;
3271 purge_addressof_replacements = 0;
3274 /* Pass through the INSNS of function FNDECL and convert virtual register
3275 references to hard register references. */
3278 instantiate_virtual_regs (fndecl, insns)
3285 /* Compute the offsets to use for this function. */
3286 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3287 var_offset = STARTING_FRAME_OFFSET;
3288 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3289 out_arg_offset = STACK_POINTER_OFFSET;
3290 cfa_offset = ARG_POINTER_CFA_OFFSET;
3292 /* Scan all variables and parameters of this function. For each that is
3293 in memory, instantiate all virtual registers if the result is a valid
3294 address. If not, we do it later. That will handle most uses of virtual
3295 regs on many machines. */
3296 instantiate_decls (fndecl, 1);
3298 /* Initialize recognition, indicating that volatile is OK. */
3301 /* Scan through all the insns, instantiating every virtual register still
3303 for (insn = insns; insn; insn = NEXT_INSN (insn))
3304 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3305 || GET_CODE (insn) == CALL_INSN)
3307 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3308 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3311 /* Instantiate the stack slots for the parm registers, for later use in
3312 addressof elimination. */
3313 for (i = 0; i < max_parm_reg; ++i)
3314 if (parm_reg_stack_loc[i])
3315 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3317 /* Now instantiate the remaining register equivalences for debugging info.
3318 These will not be valid addresses. */
3319 instantiate_decls (fndecl, 0);
3321 /* Indicate that, from now on, assign_stack_local should use
3322 frame_pointer_rtx. */
3323 virtuals_instantiated = 1;
3326 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3327 all virtual registers in their DECL_RTL's.
3329 If VALID_ONLY, do this only if the resulting address is still valid.
3330 Otherwise, always do it. */
3333 instantiate_decls (fndecl, valid_only)
3339 if (DECL_SAVED_INSNS (fndecl))
3340 /* When compiling an inline function, the obstack used for
3341 rtl allocation is the maybepermanent_obstack. Calling
3342 `resume_temporary_allocation' switches us back to that
3343 obstack while we process this function's parameters. */
3344 resume_temporary_allocation ();
3346 /* Process all parameters of the function. */
3347 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3349 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3351 instantiate_decl (DECL_RTL (decl), size, valid_only);
3353 /* If the parameter was promoted, then the incoming RTL mode may be
3354 larger than the declared type size. We must use the larger of
3356 size = MAX (GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl))), size);
3357 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3360 /* Now process all variables defined in the function or its subblocks. */
3361 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3363 if (DECL_INLINE (fndecl) || DECL_DEFER_OUTPUT (fndecl))
3365 /* Save all rtl allocated for this function by raising the
3366 high-water mark on the maybepermanent_obstack. */
3368 /* All further rtl allocation is now done in the current_obstack. */
3369 rtl_in_current_obstack ();
3373 /* Subroutine of instantiate_decls: Process all decls in the given
3374 BLOCK node and all its subblocks. */
3377 instantiate_decls_1 (let, valid_only)
3383 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3384 instantiate_decl (DECL_RTL (t), int_size_in_bytes (TREE_TYPE (t)),
3387 /* Process all subblocks. */
3388 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3389 instantiate_decls_1 (t, valid_only);
3392 /* Subroutine of the preceding procedures: Given RTL representing a
3393 decl and the size of the object, do any instantiation required.
3395 If VALID_ONLY is non-zero, it means that the RTL should only be
3396 changed if the new address is valid. */
3399 instantiate_decl (x, size, valid_only)
3404 enum machine_mode mode;
3407 /* If this is not a MEM, no need to do anything. Similarly if the
3408 address is a constant or a register that is not a virtual register. */
3410 if (x == 0 || GET_CODE (x) != MEM)
3414 if (CONSTANT_P (addr)
3415 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3416 || (GET_CODE (addr) == REG
3417 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3418 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3421 /* If we should only do this if the address is valid, copy the address.
3422 We need to do this so we can undo any changes that might make the
3423 address invalid. This copy is unfortunate, but probably can't be
3427 addr = copy_rtx (addr);
3429 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3433 /* Now verify that the resulting address is valid for every integer or
3434 floating-point mode up to and including SIZE bytes long. We do this
3435 since the object might be accessed in any mode and frame addresses
3438 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3439 mode != VOIDmode && GET_MODE_SIZE (mode) <= size;
3440 mode = GET_MODE_WIDER_MODE (mode))
3441 if (! memory_address_p (mode, addr))
3444 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3445 mode != VOIDmode && GET_MODE_SIZE (mode) <= size;
3446 mode = GET_MODE_WIDER_MODE (mode))
3447 if (! memory_address_p (mode, addr))
3451 /* Put back the address now that we have updated it and we either know
3452 it is valid or we don't care whether it is valid. */
3457 /* Given a pointer to a piece of rtx and an optional pointer to the
3458 containing object, instantiate any virtual registers present in it.
3460 If EXTRA_INSNS, we always do the replacement and generate
3461 any extra insns before OBJECT. If it zero, we do nothing if replacement
3464 Return 1 if we either had nothing to do or if we were able to do the
3465 needed replacement. Return 0 otherwise; we only return zero if
3466 EXTRA_INSNS is zero.
3468 We first try some simple transformations to avoid the creation of extra
3472 instantiate_virtual_regs_1 (loc, object, extra_insns)
3480 HOST_WIDE_INT offset = 0;
3486 /* Re-start here to avoid recursion in common cases. */
3493 code = GET_CODE (x);
3495 /* Check for some special cases. */
3512 /* We are allowed to set the virtual registers. This means that
3513 the actual register should receive the source minus the
3514 appropriate offset. This is used, for example, in the handling
3515 of non-local gotos. */
3516 if (SET_DEST (x) == virtual_incoming_args_rtx)
3517 new = arg_pointer_rtx, offset = - in_arg_offset;
3518 else if (SET_DEST (x) == virtual_stack_vars_rtx)
3519 new = frame_pointer_rtx, offset = - var_offset;
3520 else if (SET_DEST (x) == virtual_stack_dynamic_rtx)
3521 new = stack_pointer_rtx, offset = - dynamic_offset;
3522 else if (SET_DEST (x) == virtual_outgoing_args_rtx)
3523 new = stack_pointer_rtx, offset = - out_arg_offset;
3524 else if (SET_DEST (x) == virtual_cfa_rtx)
3525 new = arg_pointer_rtx, offset = - cfa_offset;
3529 rtx src = SET_SRC (x);
3531 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3533 /* The only valid sources here are PLUS or REG. Just do
3534 the simplest possible thing to handle them. */
3535 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3539 if (GET_CODE (src) != REG)
3540 temp = force_operand (src, NULL_RTX);
3543 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3547 emit_insns_before (seq, object);
3550 if (! validate_change (object, &SET_SRC (x), temp, 0)
3557 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3562 /* Handle special case of virtual register plus constant. */
3563 if (CONSTANT_P (XEXP (x, 1)))
3565 rtx old, new_offset;
3567 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3568 if (GET_CODE (XEXP (x, 0)) == PLUS)
3570 rtx inner = XEXP (XEXP (x, 0), 0);
3572 if (inner == virtual_incoming_args_rtx)
3573 new = arg_pointer_rtx, offset = in_arg_offset;
3574 else if (inner == virtual_stack_vars_rtx)
3575 new = frame_pointer_rtx, offset = var_offset;
3576 else if (inner == virtual_stack_dynamic_rtx)
3577 new = stack_pointer_rtx, offset = dynamic_offset;
3578 else if (inner == virtual_outgoing_args_rtx)
3579 new = stack_pointer_rtx, offset = out_arg_offset;
3580 else if (inner == virtual_cfa_rtx)
3581 new = arg_pointer_rtx, offset = cfa_offset;
3588 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3590 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3593 else if (XEXP (x, 0) == virtual_incoming_args_rtx)
3594 new = arg_pointer_rtx, offset = in_arg_offset;
3595 else if (XEXP (x, 0) == virtual_stack_vars_rtx)
3596 new = frame_pointer_rtx, offset = var_offset;
3597 else if (XEXP (x, 0) == virtual_stack_dynamic_rtx)
3598 new = stack_pointer_rtx, offset = dynamic_offset;
3599 else if (XEXP (x, 0) == virtual_outgoing_args_rtx)
3600 new = stack_pointer_rtx, offset = out_arg_offset;
3601 else if (XEXP (x, 0) == virtual_cfa_rtx)
3602 new = arg_pointer_rtx, offset = cfa_offset;
3605 /* We know the second operand is a constant. Unless the
3606 first operand is a REG (which has been already checked),
3607 it needs to be checked. */
3608 if (GET_CODE (XEXP (x, 0)) != REG)
3616 new_offset = plus_constant (XEXP (x, 1), offset);
3618 /* If the new constant is zero, try to replace the sum with just
3620 if (new_offset == const0_rtx
3621 && validate_change (object, loc, new, 0))
3624 /* Next try to replace the register and new offset.
3625 There are two changes to validate here and we can't assume that
3626 in the case of old offset equals new just changing the register
3627 will yield a valid insn. In the interests of a little efficiency,
3628 however, we only call validate change once (we don't queue up the
3629 changes and then call apply_change_group). */
3633 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3634 : (XEXP (x, 0) = new,
3635 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3643 /* Otherwise copy the new constant into a register and replace
3644 constant with that register. */
3645 temp = gen_reg_rtx (Pmode);
3647 if (validate_change (object, &XEXP (x, 1), temp, 0))
3648 emit_insn_before (gen_move_insn (temp, new_offset), object);
3651 /* If that didn't work, replace this expression with a
3652 register containing the sum. */
3655 new = gen_rtx_PLUS (Pmode, new, new_offset);
3658 temp = force_operand (new, NULL_RTX);
3662 emit_insns_before (seq, object);
3663 if (! validate_change (object, loc, temp, 0)
3664 && ! validate_replace_rtx (x, temp, object))
3672 /* Fall through to generic two-operand expression case. */
3678 case DIV: case UDIV:
3679 case MOD: case UMOD:
3680 case AND: case IOR: case XOR:
3681 case ROTATERT: case ROTATE:
3682 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3684 case GE: case GT: case GEU: case GTU:
3685 case LE: case LT: case LEU: case LTU:
3686 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3687 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3692 /* Most cases of MEM that convert to valid addresses have already been
3693 handled by our scan of decls. The only special handling we
3694 need here is to make a copy of the rtx to ensure it isn't being
3695 shared if we have to change it to a pseudo.
3697 If the rtx is a simple reference to an address via a virtual register,
3698 it can potentially be shared. In such cases, first try to make it
3699 a valid address, which can also be shared. Otherwise, copy it and
3702 First check for common cases that need no processing. These are
3703 usually due to instantiation already being done on a previous instance
3707 if (CONSTANT_ADDRESS_P (temp)
3708 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3709 || temp == arg_pointer_rtx
3711 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3712 || temp == hard_frame_pointer_rtx
3714 || temp == frame_pointer_rtx)
3717 if (GET_CODE (temp) == PLUS
3718 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3719 && (XEXP (temp, 0) == frame_pointer_rtx
3720 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3721 || XEXP (temp, 0) == hard_frame_pointer_rtx
3723 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3724 || XEXP (temp, 0) == arg_pointer_rtx
3729 if (temp == virtual_stack_vars_rtx
3730 || temp == virtual_incoming_args_rtx
3731 || (GET_CODE (temp) == PLUS
3732 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3733 && (XEXP (temp, 0) == virtual_stack_vars_rtx
3734 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
3736 /* This MEM may be shared. If the substitution can be done without
3737 the need to generate new pseudos, we want to do it in place
3738 so all copies of the shared rtx benefit. The call below will
3739 only make substitutions if the resulting address is still
3742 Note that we cannot pass X as the object in the recursive call
3743 since the insn being processed may not allow all valid
3744 addresses. However, if we were not passed on object, we can
3745 only modify X without copying it if X will have a valid
3748 ??? Also note that this can still lose if OBJECT is an insn that
3749 has less restrictions on an address that some other insn.
3750 In that case, we will modify the shared address. This case
3751 doesn't seem very likely, though. One case where this could
3752 happen is in the case of a USE or CLOBBER reference, but we
3753 take care of that below. */
3755 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
3756 object ? object : x, 0))
3759 /* Otherwise make a copy and process that copy. We copy the entire
3760 RTL expression since it might be a PLUS which could also be
3762 *loc = x = copy_rtx (x);
3765 /* Fall through to generic unary operation case. */
3767 case STRICT_LOW_PART:
3769 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
3770 case SIGN_EXTEND: case ZERO_EXTEND:
3771 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
3772 case FLOAT: case FIX:
3773 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
3777 /* These case either have just one operand or we know that we need not
3778 check the rest of the operands. */
3784 /* If the operand is a MEM, see if the change is a valid MEM. If not,
3785 go ahead and make the invalid one, but do it to a copy. For a REG,
3786 just make the recursive call, since there's no chance of a problem. */
3788 if ((GET_CODE (XEXP (x, 0)) == MEM
3789 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
3791 || (GET_CODE (XEXP (x, 0)) == REG
3792 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
3795 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
3800 /* Try to replace with a PLUS. If that doesn't work, compute the sum
3801 in front of this insn and substitute the temporary. */
3802 if (x == virtual_incoming_args_rtx)
3803 new = arg_pointer_rtx, offset = in_arg_offset;
3804 else if (x == virtual_stack_vars_rtx)
3805 new = frame_pointer_rtx, offset = var_offset;
3806 else if (x == virtual_stack_dynamic_rtx)
3807 new = stack_pointer_rtx, offset = dynamic_offset;
3808 else if (x == virtual_outgoing_args_rtx)
3809 new = stack_pointer_rtx, offset = out_arg_offset;
3810 else if (x == virtual_cfa_rtx)
3811 new = arg_pointer_rtx, offset = cfa_offset;
3815 temp = plus_constant (new, offset);
3816 if (!validate_change (object, loc, temp, 0))
3822 temp = force_operand (temp, NULL_RTX);
3826 emit_insns_before (seq, object);
3827 if (! validate_change (object, loc, temp, 0)
3828 && ! validate_replace_rtx (x, temp, object))
3836 if (GET_CODE (XEXP (x, 0)) == REG)
3839 else if (GET_CODE (XEXP (x, 0)) == MEM)
3841 /* If we have a (addressof (mem ..)), do any instantiation inside
3842 since we know we'll be making the inside valid when we finally
3843 remove the ADDRESSOF. */
3844 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
3853 /* Scan all subexpressions. */
3854 fmt = GET_RTX_FORMAT (code);
3855 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3858 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
3861 else if (*fmt == 'E')
3862 for (j = 0; j < XVECLEN (x, i); j++)
3863 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
3870 /* Optimization: assuming this function does not receive nonlocal gotos,
3871 delete the handlers for such, as well as the insns to establish
3872 and disestablish them. */
3878 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3880 /* Delete the handler by turning off the flag that would
3881 prevent jump_optimize from deleting it.
3882 Also permit deletion of the nonlocal labels themselves
3883 if nothing local refers to them. */
3884 if (GET_CODE (insn) == CODE_LABEL)
3888 LABEL_PRESERVE_P (insn) = 0;
3890 /* Remove it from the nonlocal_label list, to avoid confusing
3892 for (t = nonlocal_labels, last_t = 0; t;
3893 last_t = t, t = TREE_CHAIN (t))
3894 if (DECL_RTL (TREE_VALUE (t)) == insn)
3899 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
3901 TREE_CHAIN (last_t) = TREE_CHAIN (t);
3904 if (GET_CODE (insn) == INSN)
3908 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
3909 if (reg_mentioned_p (t, PATTERN (insn)))
3915 || (nonlocal_goto_stack_level != 0
3916 && reg_mentioned_p (nonlocal_goto_stack_level,
3926 return max_parm_reg;
3929 /* Return the first insn following those generated by `assign_parms'. */
3932 get_first_nonparm_insn ()
3935 return NEXT_INSN (last_parm_insn);
3936 return get_insns ();
3939 /* Return the first NOTE_INSN_BLOCK_BEG note in the function.
3940 Crash if there is none. */
3943 get_first_block_beg ()
3945 register rtx searcher;
3946 register rtx insn = get_first_nonparm_insn ();
3948 for (searcher = insn; searcher; searcher = NEXT_INSN (searcher))
3949 if (GET_CODE (searcher) == NOTE
3950 && NOTE_LINE_NUMBER (searcher) == NOTE_INSN_BLOCK_BEG)
3953 abort (); /* Invalid call to this function. (See comments above.) */
3957 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
3958 This means a type for which function calls must pass an address to the
3959 function or get an address back from the function.
3960 EXP may be a type node or an expression (whose type is tested). */
3963 aggregate_value_p (exp)
3966 int i, regno, nregs;
3969 if (TREE_CODE_CLASS (TREE_CODE (exp)) == 't')
3972 type = TREE_TYPE (exp);
3974 if (RETURN_IN_MEMORY (type))
3976 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
3977 and thus can't be returned in registers. */
3978 if (TREE_ADDRESSABLE (type))
3980 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
3982 /* Make sure we have suitable call-clobbered regs to return
3983 the value in; if not, we must return it in memory. */
3984 reg = hard_function_value (type, 0, 0);
3986 /* If we have something other than a REG (e.g. a PARALLEL), then assume
3988 if (GET_CODE (reg) != REG)
3991 regno = REGNO (reg);
3992 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
3993 for (i = 0; i < nregs; i++)
3994 if (! call_used_regs[regno + i])
3999 /* Assign RTL expressions to the function's parameters.
4000 This may involve copying them into registers and using
4001 those registers as the RTL for them. */
4004 assign_parms (fndecl)
4008 register rtx entry_parm = 0;
4009 register rtx stack_parm = 0;
4010 CUMULATIVE_ARGS args_so_far;
4011 enum machine_mode promoted_mode, passed_mode;
4012 enum machine_mode nominal_mode, promoted_nominal_mode;
4014 /* Total space needed so far for args on the stack,
4015 given as a constant and a tree-expression. */
4016 struct args_size stack_args_size;
4017 tree fntype = TREE_TYPE (fndecl);
4018 tree fnargs = DECL_ARGUMENTS (fndecl);
4019 /* This is used for the arg pointer when referring to stack args. */
4020 rtx internal_arg_pointer;
4021 /* This is a dummy PARM_DECL that we used for the function result if
4022 the function returns a structure. */
4023 tree function_result_decl = 0;
4024 #ifdef SETUP_INCOMING_VARARGS
4025 int varargs_setup = 0;
4027 rtx conversion_insns = 0;
4028 struct args_size alignment_pad;
4030 /* Nonzero if the last arg is named `__builtin_va_alist',
4031 which is used on some machines for old-fashioned non-ANSI varargs.h;
4032 this should be stuck onto the stack as if it had arrived there. */
4034 = (current_function_varargs
4036 && (parm = tree_last (fnargs)) != 0
4038 && (! strcmp (IDENTIFIER_POINTER (DECL_NAME (parm)),
4039 "__builtin_va_alist")));
4041 /* Nonzero if function takes extra anonymous args.
4042 This means the last named arg must be on the stack
4043 right before the anonymous ones. */
4045 = (TYPE_ARG_TYPES (fntype) != 0
4046 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4047 != void_type_node));
4049 current_function_stdarg = stdarg;
4051 /* If the reg that the virtual arg pointer will be translated into is
4052 not a fixed reg or is the stack pointer, make a copy of the virtual
4053 arg pointer, and address parms via the copy. The frame pointer is
4054 considered fixed even though it is not marked as such.
4056 The second time through, simply use ap to avoid generating rtx. */
4058 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4059 || ! (fixed_regs[ARG_POINTER_REGNUM]
4060 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4061 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4063 internal_arg_pointer = virtual_incoming_args_rtx;
4064 current_function_internal_arg_pointer = internal_arg_pointer;
4066 stack_args_size.constant = 0;
4067 stack_args_size.var = 0;
4069 /* If struct value address is treated as the first argument, make it so. */
4070 if (aggregate_value_p (DECL_RESULT (fndecl))
4071 && ! current_function_returns_pcc_struct
4072 && struct_value_incoming_rtx == 0)
4074 tree type = build_pointer_type (TREE_TYPE (fntype));
4076 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4078 DECL_ARG_TYPE (function_result_decl) = type;
4079 TREE_CHAIN (function_result_decl) = fnargs;
4080 fnargs = function_result_decl;
4083 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4084 parm_reg_stack_loc = (rtx *) xcalloc (max_parm_reg, sizeof (rtx));
4086 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4087 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4089 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, 0);
4092 /* We haven't yet found an argument that we must push and pretend the
4094 current_function_pretend_args_size = 0;
4096 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4098 int aggregate = AGGREGATE_TYPE_P (TREE_TYPE (parm));
4099 struct args_size stack_offset;
4100 struct args_size arg_size;
4101 int passed_pointer = 0;
4102 int did_conversion = 0;
4103 tree passed_type = DECL_ARG_TYPE (parm);
4104 tree nominal_type = TREE_TYPE (parm);
4107 /* Set LAST_NAMED if this is last named arg before some
4109 int last_named = ((TREE_CHAIN (parm) == 0
4110 || DECL_NAME (TREE_CHAIN (parm)) == 0)
4111 && (stdarg || current_function_varargs));
4112 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4113 most machines, if this is a varargs/stdarg function, then we treat
4114 the last named arg as if it were anonymous too. */
4115 int named_arg = STRICT_ARGUMENT_NAMING ? 1 : ! last_named;
4117 if (TREE_TYPE (parm) == error_mark_node
4118 /* This can happen after weird syntax errors
4119 or if an enum type is defined among the parms. */
4120 || TREE_CODE (parm) != PARM_DECL
4121 || passed_type == NULL)
4123 DECL_INCOMING_RTL (parm) = DECL_RTL (parm)
4124 = gen_rtx_MEM (BLKmode, const0_rtx);
4125 TREE_USED (parm) = 1;
4129 /* For varargs.h function, save info about regs and stack space
4130 used by the individual args, not including the va_alist arg. */
4131 if (hide_last_arg && last_named)
4132 current_function_args_info = args_so_far;
4134 /* Find mode of arg as it is passed, and mode of arg
4135 as it should be during execution of this function. */
4136 passed_mode = TYPE_MODE (passed_type);
4137 nominal_mode = TYPE_MODE (nominal_type);
4139 /* If the parm's mode is VOID, its value doesn't matter,
4140 and avoid the usual things like emit_move_insn that could crash. */
4141 if (nominal_mode == VOIDmode)
4143 DECL_INCOMING_RTL (parm) = DECL_RTL (parm) = const0_rtx;
4147 /* If the parm is to be passed as a transparent union, use the
4148 type of the first field for the tests below. We have already
4149 verified that the modes are the same. */
4150 if (DECL_TRANSPARENT_UNION (parm)
4151 || TYPE_TRANSPARENT_UNION (passed_type))
4152 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4154 /* See if this arg was passed by invisible reference. It is if
4155 it is an object whose size depends on the contents of the
4156 object itself or if the machine requires these objects be passed
4159 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
4160 && contains_placeholder_p (TYPE_SIZE (passed_type)))
4161 || TREE_ADDRESSABLE (passed_type)
4162 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4163 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4164 passed_type, named_arg)
4168 passed_type = nominal_type = build_pointer_type (passed_type);
4170 passed_mode = nominal_mode = Pmode;
4173 promoted_mode = passed_mode;
4175 #ifdef PROMOTE_FUNCTION_ARGS
4176 /* Compute the mode in which the arg is actually extended to. */
4177 unsignedp = TREE_UNSIGNED (passed_type);
4178 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4181 /* Let machine desc say which reg (if any) the parm arrives in.
4182 0 means it arrives on the stack. */
4183 #ifdef FUNCTION_INCOMING_ARG
4184 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4185 passed_type, named_arg);
4187 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4188 passed_type, named_arg);
4191 if (entry_parm == 0)
4192 promoted_mode = passed_mode;
4194 #ifdef SETUP_INCOMING_VARARGS
4195 /* If this is the last named parameter, do any required setup for
4196 varargs or stdargs. We need to know about the case of this being an
4197 addressable type, in which case we skip the registers it
4198 would have arrived in.
4200 For stdargs, LAST_NAMED will be set for two parameters, the one that
4201 is actually the last named, and the dummy parameter. We only
4202 want to do this action once.
4204 Also, indicate when RTL generation is to be suppressed. */
4205 if (last_named && !varargs_setup)
4207 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
4208 current_function_pretend_args_size, 0);
4213 /* Determine parm's home in the stack,
4214 in case it arrives in the stack or we should pretend it did.
4216 Compute the stack position and rtx where the argument arrives
4219 There is one complexity here: If this was a parameter that would
4220 have been passed in registers, but wasn't only because it is
4221 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4222 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4223 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4224 0 as it was the previous time. */
4226 pretend_named = named_arg || PRETEND_OUTGOING_VARARGS_NAMED;
4227 locate_and_pad_parm (promoted_mode, passed_type,
4228 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4231 #ifdef FUNCTION_INCOMING_ARG
4232 FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4234 pretend_named) != 0,
4236 FUNCTION_ARG (args_so_far, promoted_mode,
4238 pretend_named) != 0,
4241 fndecl, &stack_args_size, &stack_offset, &arg_size,
4245 rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
4247 if (offset_rtx == const0_rtx)
4248 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4250 stack_parm = gen_rtx_MEM (promoted_mode,
4251 gen_rtx_PLUS (Pmode,
4252 internal_arg_pointer,
4255 /* If this is a memory ref that contains aggregate components,
4256 mark it as such for cse and loop optimize. Likewise if it
4258 MEM_SET_IN_STRUCT_P (stack_parm, aggregate);
4259 RTX_UNCHANGING_P (stack_parm) = TREE_READONLY (parm);
4260 MEM_ALIAS_SET (stack_parm) = get_alias_set (parm);
4263 /* If this parameter was passed both in registers and in the stack,
4264 use the copy on the stack. */
4265 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4268 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4269 /* If this parm was passed part in regs and part in memory,
4270 pretend it arrived entirely in memory
4271 by pushing the register-part onto the stack.
4273 In the special case of a DImode or DFmode that is split,
4274 we could put it together in a pseudoreg directly,
4275 but for now that's not worth bothering with. */
4279 int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4280 passed_type, named_arg);
4284 current_function_pretend_args_size
4285 = (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
4286 / (PARM_BOUNDARY / BITS_PER_UNIT)
4287 * (PARM_BOUNDARY / BITS_PER_UNIT));
4289 /* Handle calls that pass values in multiple non-contiguous
4290 locations. The Irix 6 ABI has examples of this. */
4291 if (GET_CODE (entry_parm) == PARALLEL)
4292 emit_group_store (validize_mem (stack_parm), entry_parm,
4293 int_size_in_bytes (TREE_TYPE (parm)),
4294 (TYPE_ALIGN (TREE_TYPE (parm))
4297 move_block_from_reg (REGNO (entry_parm),
4298 validize_mem (stack_parm), nregs,
4299 int_size_in_bytes (TREE_TYPE (parm)));
4301 entry_parm = stack_parm;
4306 /* If we didn't decide this parm came in a register,
4307 by default it came on the stack. */
4308 if (entry_parm == 0)
4309 entry_parm = stack_parm;
4311 /* Record permanently how this parm was passed. */
4312 DECL_INCOMING_RTL (parm) = entry_parm;
4314 /* If there is actually space on the stack for this parm,
4315 count it in stack_args_size; otherwise set stack_parm to 0
4316 to indicate there is no preallocated stack slot for the parm. */
4318 if (entry_parm == stack_parm
4319 || (GET_CODE (entry_parm) == PARALLEL
4320 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4321 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4322 /* On some machines, even if a parm value arrives in a register
4323 there is still an (uninitialized) stack slot allocated for it.
4325 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4326 whether this parameter already has a stack slot allocated,
4327 because an arg block exists only if current_function_args_size
4328 is larger than some threshold, and we haven't calculated that
4329 yet. So, for now, we just assume that stack slots never exist
4331 || REG_PARM_STACK_SPACE (fndecl) > 0
4335 stack_args_size.constant += arg_size.constant;
4337 ADD_PARM_SIZE (stack_args_size, arg_size.var);
4340 /* No stack slot was pushed for this parm. */
4343 /* Update info on where next arg arrives in registers. */
4345 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4346 passed_type, named_arg);
4348 /* If we can't trust the parm stack slot to be aligned enough
4349 for its ultimate type, don't use that slot after entry.
4350 We'll make another stack slot, if we need one. */
4352 unsigned int thisparm_boundary
4353 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4355 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4359 /* If parm was passed in memory, and we need to convert it on entry,
4360 don't store it back in that same slot. */
4362 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4366 /* Now adjust STACK_PARM to the mode and precise location
4367 where this parameter should live during execution,
4368 if we discover that it must live in the stack during execution.
4369 To make debuggers happier on big-endian machines, we store
4370 the value in the last bytes of the space available. */
4372 if (nominal_mode != BLKmode && nominal_mode != passed_mode
4377 if (BYTES_BIG_ENDIAN
4378 && GET_MODE_SIZE (nominal_mode) < UNITS_PER_WORD)
4379 stack_offset.constant += (GET_MODE_SIZE (passed_mode)
4380 - GET_MODE_SIZE (nominal_mode));
4382 offset_rtx = ARGS_SIZE_RTX (stack_offset);
4383 if (offset_rtx == const0_rtx)
4384 stack_parm = gen_rtx_MEM (nominal_mode, internal_arg_pointer);
4386 stack_parm = gen_rtx_MEM (nominal_mode,
4387 gen_rtx_PLUS (Pmode,
4388 internal_arg_pointer,
4391 /* If this is a memory ref that contains aggregate components,
4392 mark it as such for cse and loop optimize. */
4393 MEM_SET_IN_STRUCT_P (stack_parm, aggregate);
4397 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4398 in the mode in which it arrives.
4399 STACK_PARM is an RTX for a stack slot where the parameter can live
4400 during the function (in case we want to put it there).
4401 STACK_PARM is 0 if no stack slot was pushed for it.
4403 Now output code if necessary to convert ENTRY_PARM to
4404 the type in which this function declares it,
4405 and store that result in an appropriate place,
4406 which may be a pseudo reg, may be STACK_PARM,
4407 or may be a local stack slot if STACK_PARM is 0.
4409 Set DECL_RTL to that place. */
4411 if (nominal_mode == BLKmode || GET_CODE (entry_parm) == PARALLEL)
4413 /* If a BLKmode arrives in registers, copy it to a stack slot.
4414 Handle calls that pass values in multiple non-contiguous
4415 locations. The Irix 6 ABI has examples of this. */
4416 if (GET_CODE (entry_parm) == REG
4417 || GET_CODE (entry_parm) == PARALLEL)
4420 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
4423 /* Note that we will be storing an integral number of words.
4424 So we have to be careful to ensure that we allocate an
4425 integral number of words. We do this below in the
4426 assign_stack_local if space was not allocated in the argument
4427 list. If it was, this will not work if PARM_BOUNDARY is not
4428 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4429 if it becomes a problem. */
4431 if (stack_parm == 0)
4434 = assign_stack_local (GET_MODE (entry_parm),
4437 /* If this is a memory ref that contains aggregate
4438 components, mark it as such for cse and loop optimize. */
4439 MEM_SET_IN_STRUCT_P (stack_parm, aggregate);
4442 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4445 if (TREE_READONLY (parm))
4446 RTX_UNCHANGING_P (stack_parm) = 1;
4448 /* Handle calls that pass values in multiple non-contiguous
4449 locations. The Irix 6 ABI has examples of this. */
4450 if (GET_CODE (entry_parm) == PARALLEL)
4451 emit_group_store (validize_mem (stack_parm), entry_parm,
4452 int_size_in_bytes (TREE_TYPE (parm)),
4453 (TYPE_ALIGN (TREE_TYPE (parm))
4456 move_block_from_reg (REGNO (entry_parm),
4457 validize_mem (stack_parm),
4458 size_stored / UNITS_PER_WORD,
4459 int_size_in_bytes (TREE_TYPE (parm)));
4461 DECL_RTL (parm) = stack_parm;
4463 else if (! ((! optimize
4464 && ! DECL_REGISTER (parm)
4465 && ! DECL_INLINE (fndecl))
4466 /* layout_decl may set this. */
4467 || TREE_ADDRESSABLE (parm)
4468 || TREE_SIDE_EFFECTS (parm)
4469 /* If -ffloat-store specified, don't put explicit
4470 float variables into registers. */
4471 || (flag_float_store
4472 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4473 /* Always assign pseudo to structure return or item passed
4474 by invisible reference. */
4475 || passed_pointer || parm == function_result_decl)
4477 /* Store the parm in a pseudoregister during the function, but we
4478 may need to do it in a wider mode. */
4480 register rtx parmreg;
4481 int regno, regnoi = 0, regnor = 0;
4483 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4485 promoted_nominal_mode
4486 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4488 parmreg = gen_reg_rtx (promoted_nominal_mode);
4489 mark_user_reg (parmreg);
4491 /* If this was an item that we received a pointer to, set DECL_RTL
4496 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)), parmreg);
4497 MEM_SET_IN_STRUCT_P (DECL_RTL (parm), aggregate);
4500 DECL_RTL (parm) = parmreg;
4502 /* Copy the value into the register. */
4503 if (nominal_mode != passed_mode
4504 || promoted_nominal_mode != promoted_mode)
4507 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4508 mode, by the caller. We now have to convert it to
4509 NOMINAL_MODE, if different. However, PARMREG may be in
4510 a different mode than NOMINAL_MODE if it is being stored
4513 If ENTRY_PARM is a hard register, it might be in a register
4514 not valid for operating in its mode (e.g., an odd-numbered
4515 register for a DFmode). In that case, moves are the only
4516 thing valid, so we can't do a convert from there. This
4517 occurs when the calling sequence allow such misaligned
4520 In addition, the conversion may involve a call, which could
4521 clobber parameters which haven't been copied to pseudo
4522 registers yet. Therefore, we must first copy the parm to
4523 a pseudo reg here, and save the conversion until after all
4524 parameters have been moved. */
4526 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4528 emit_move_insn (tempreg, validize_mem (entry_parm));
4530 push_to_sequence (conversion_insns);
4531 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4533 /* TREE_USED gets set erroneously during expand_assignment. */
4534 save_tree_used = TREE_USED (parm);
4535 expand_assignment (parm,
4536 make_tree (nominal_type, tempreg), 0, 0);
4537 TREE_USED (parm) = save_tree_used;
4538 conversion_insns = get_insns ();
4543 emit_move_insn (parmreg, validize_mem (entry_parm));
4545 /* If we were passed a pointer but the actual value
4546 can safely live in a register, put it in one. */
4547 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4549 && ! DECL_REGISTER (parm)
4550 && ! DECL_INLINE (fndecl))
4551 /* layout_decl may set this. */
4552 || TREE_ADDRESSABLE (parm)
4553 || TREE_SIDE_EFFECTS (parm)
4554 /* If -ffloat-store specified, don't put explicit
4555 float variables into registers. */
4556 || (flag_float_store
4557 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE)))
4559 /* We can't use nominal_mode, because it will have been set to
4560 Pmode above. We must use the actual mode of the parm. */
4561 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4562 mark_user_reg (parmreg);
4563 emit_move_insn (parmreg, DECL_RTL (parm));
4564 DECL_RTL (parm) = parmreg;
4565 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4569 #ifdef FUNCTION_ARG_CALLEE_COPIES
4570 /* If we are passed an arg by reference and it is our responsibility
4571 to make a copy, do it now.
4572 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4573 original argument, so we must recreate them in the call to
4574 FUNCTION_ARG_CALLEE_COPIES. */
4575 /* ??? Later add code to handle the case that if the argument isn't
4576 modified, don't do the copy. */
4578 else if (passed_pointer
4579 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4580 TYPE_MODE (DECL_ARG_TYPE (parm)),
4581 DECL_ARG_TYPE (parm),
4583 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4586 tree type = DECL_ARG_TYPE (parm);
4588 /* This sequence may involve a library call perhaps clobbering
4589 registers that haven't been copied to pseudos yet. */
4591 push_to_sequence (conversion_insns);
4593 if (TYPE_SIZE (type) == 0
4594 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4595 /* This is a variable sized object. */
4596 copy = gen_rtx_MEM (BLKmode,
4597 allocate_dynamic_stack_space
4598 (expr_size (parm), NULL_RTX,
4599 TYPE_ALIGN (type)));
4601 copy = assign_stack_temp (TYPE_MODE (type),
4602 int_size_in_bytes (type), 1);
4603 MEM_SET_IN_STRUCT_P (copy, AGGREGATE_TYPE_P (type));
4604 RTX_UNCHANGING_P (copy) = TREE_READONLY (parm);
4606 store_expr (parm, copy, 0);
4607 emit_move_insn (parmreg, XEXP (copy, 0));
4608 if (current_function_check_memory_usage)
4609 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
4610 XEXP (copy, 0), Pmode,
4611 GEN_INT (int_size_in_bytes (type)),
4612 TYPE_MODE (sizetype),
4613 GEN_INT (MEMORY_USE_RW),
4614 TYPE_MODE (integer_type_node));
4615 conversion_insns = get_insns ();
4619 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4621 /* In any case, record the parm's desired stack location
4622 in case we later discover it must live in the stack.
4624 If it is a COMPLEX value, store the stack location for both
4627 if (GET_CODE (parmreg) == CONCAT)
4628 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4630 regno = REGNO (parmreg);
4632 if (regno >= max_parm_reg)
4635 int old_max_parm_reg = max_parm_reg;
4637 /* It's slow to expand this one register at a time,
4638 but it's also rare and we need max_parm_reg to be
4639 precisely correct. */
4640 max_parm_reg = regno + 1;
4641 new = (rtx *) xrealloc (parm_reg_stack_loc,
4642 max_parm_reg * sizeof (rtx));
4643 bzero ((char *) (new + old_max_parm_reg),
4644 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4645 parm_reg_stack_loc = new;
4648 if (GET_CODE (parmreg) == CONCAT)
4650 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
4652 regnor = REGNO (gen_realpart (submode, parmreg));
4653 regnoi = REGNO (gen_imagpart (submode, parmreg));
4655 if (stack_parm != 0)
4657 parm_reg_stack_loc[regnor]
4658 = gen_realpart (submode, stack_parm);
4659 parm_reg_stack_loc[regnoi]
4660 = gen_imagpart (submode, stack_parm);
4664 parm_reg_stack_loc[regnor] = 0;
4665 parm_reg_stack_loc[regnoi] = 0;
4669 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
4671 /* Mark the register as eliminable if we did no conversion
4672 and it was copied from memory at a fixed offset,
4673 and the arg pointer was not copied to a pseudo-reg.
4674 If the arg pointer is a pseudo reg or the offset formed
4675 an invalid address, such memory-equivalences
4676 as we make here would screw up life analysis for it. */
4677 if (nominal_mode == passed_mode
4680 && GET_CODE (stack_parm) == MEM
4681 && stack_offset.var == 0
4682 && reg_mentioned_p (virtual_incoming_args_rtx,
4683 XEXP (stack_parm, 0)))
4685 rtx linsn = get_last_insn ();
4688 /* Mark complex types separately. */
4689 if (GET_CODE (parmreg) == CONCAT)
4690 /* Scan backwards for the set of the real and
4692 for (sinsn = linsn; sinsn != 0;
4693 sinsn = prev_nonnote_insn (sinsn))
4695 set = single_set (sinsn);
4697 && SET_DEST (set) == regno_reg_rtx [regnoi])
4699 = gen_rtx_EXPR_LIST (REG_EQUIV,
4700 parm_reg_stack_loc[regnoi],
4703 && SET_DEST (set) == regno_reg_rtx [regnor])
4705 = gen_rtx_EXPR_LIST (REG_EQUIV,
4706 parm_reg_stack_loc[regnor],
4709 else if ((set = single_set (linsn)) != 0
4710 && SET_DEST (set) == parmreg)
4712 = gen_rtx_EXPR_LIST (REG_EQUIV,
4713 stack_parm, REG_NOTES (linsn));
4716 /* For pointer data type, suggest pointer register. */
4717 if (POINTER_TYPE_P (TREE_TYPE (parm)))
4718 mark_reg_pointer (parmreg,
4719 (TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm)))
4724 /* Value must be stored in the stack slot STACK_PARM
4725 during function execution. */
4727 if (promoted_mode != nominal_mode)
4729 /* Conversion is required. */
4730 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4732 emit_move_insn (tempreg, validize_mem (entry_parm));
4734 push_to_sequence (conversion_insns);
4735 entry_parm = convert_to_mode (nominal_mode, tempreg,
4736 TREE_UNSIGNED (TREE_TYPE (parm)));
4739 /* ??? This may need a big-endian conversion on sparc64. */
4740 stack_parm = change_address (stack_parm, nominal_mode,
4743 conversion_insns = get_insns ();
4748 if (entry_parm != stack_parm)
4750 if (stack_parm == 0)
4753 = assign_stack_local (GET_MODE (entry_parm),
4754 GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
4755 /* If this is a memory ref that contains aggregate components,
4756 mark it as such for cse and loop optimize. */
4757 MEM_SET_IN_STRUCT_P (stack_parm, aggregate);
4760 if (promoted_mode != nominal_mode)
4762 push_to_sequence (conversion_insns);
4763 emit_move_insn (validize_mem (stack_parm),
4764 validize_mem (entry_parm));
4765 conversion_insns = get_insns ();
4769 emit_move_insn (validize_mem (stack_parm),
4770 validize_mem (entry_parm));
4772 if (current_function_check_memory_usage)
4774 push_to_sequence (conversion_insns);
4775 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
4776 XEXP (stack_parm, 0), Pmode,
4777 GEN_INT (GET_MODE_SIZE (GET_MODE
4779 TYPE_MODE (sizetype),
4780 GEN_INT (MEMORY_USE_RW),
4781 TYPE_MODE (integer_type_node));
4783 conversion_insns = get_insns ();
4786 DECL_RTL (parm) = stack_parm;
4789 /* If this "parameter" was the place where we are receiving the
4790 function's incoming structure pointer, set up the result. */
4791 if (parm == function_result_decl)
4793 tree result = DECL_RESULT (fndecl);
4794 tree restype = TREE_TYPE (result);
4797 = gen_rtx_MEM (DECL_MODE (result), DECL_RTL (parm));
4799 MEM_SET_IN_STRUCT_P (DECL_RTL (result),
4800 AGGREGATE_TYPE_P (restype));
4803 if (TREE_THIS_VOLATILE (parm))
4804 MEM_VOLATILE_P (DECL_RTL (parm)) = 1;
4805 if (TREE_READONLY (parm))
4806 RTX_UNCHANGING_P (DECL_RTL (parm)) = 1;
4809 /* Output all parameter conversion instructions (possibly including calls)
4810 now that all parameters have been copied out of hard registers. */
4811 emit_insns (conversion_insns);
4813 last_parm_insn = get_last_insn ();
4815 current_function_args_size = stack_args_size.constant;
4817 /* Adjust function incoming argument size for alignment and
4820 #ifdef REG_PARM_STACK_SPACE
4821 #ifndef MAYBE_REG_PARM_STACK_SPACE
4822 current_function_args_size = MAX (current_function_args_size,
4823 REG_PARM_STACK_SPACE (fndecl));
4827 #ifdef STACK_BOUNDARY
4828 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
4830 current_function_args_size
4831 = ((current_function_args_size + STACK_BYTES - 1)
4832 / STACK_BYTES) * STACK_BYTES;
4835 #ifdef ARGS_GROW_DOWNWARD
4836 current_function_arg_offset_rtx
4837 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
4838 : expand_expr (size_binop (MINUS_EXPR, stack_args_size.var,
4839 size_int (-stack_args_size.constant)),
4840 NULL_RTX, VOIDmode, EXPAND_MEMORY_USE_BAD));
4842 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
4845 /* See how many bytes, if any, of its args a function should try to pop
4848 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
4849 current_function_args_size);
4851 /* For stdarg.h function, save info about
4852 regs and stack space used by the named args. */
4855 current_function_args_info = args_so_far;
4857 /* Set the rtx used for the function return value. Put this in its
4858 own variable so any optimizers that need this information don't have
4859 to include tree.h. Do this here so it gets done when an inlined
4860 function gets output. */
4862 current_function_return_rtx = DECL_RTL (DECL_RESULT (fndecl));
4865 /* Indicate whether REGNO is an incoming argument to the current function
4866 that was promoted to a wider mode. If so, return the RTX for the
4867 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
4868 that REGNO is promoted from and whether the promotion was signed or
4871 #ifdef PROMOTE_FUNCTION_ARGS
4874 promoted_input_arg (regno, pmode, punsignedp)
4876 enum machine_mode *pmode;
4881 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
4882 arg = TREE_CHAIN (arg))
4883 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
4884 && REGNO (DECL_INCOMING_RTL (arg)) == regno
4885 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
4887 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
4888 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
4890 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
4891 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
4892 && mode != DECL_MODE (arg))
4894 *pmode = DECL_MODE (arg);
4895 *punsignedp = unsignedp;
4896 return DECL_INCOMING_RTL (arg);
4905 /* Compute the size and offset from the start of the stacked arguments for a
4906 parm passed in mode PASSED_MODE and with type TYPE.
4908 INITIAL_OFFSET_PTR points to the current offset into the stacked
4911 The starting offset and size for this parm are returned in *OFFSET_PTR
4912 and *ARG_SIZE_PTR, respectively.
4914 IN_REGS is non-zero if the argument will be passed in registers. It will
4915 never be set if REG_PARM_STACK_SPACE is not defined.
4917 FNDECL is the function in which the argument was defined.
4919 There are two types of rounding that are done. The first, controlled by
4920 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
4921 list to be aligned to the specific boundary (in bits). This rounding
4922 affects the initial and starting offsets, but not the argument size.
4924 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
4925 optionally rounds the size of the parm to PARM_BOUNDARY. The
4926 initial offset is not affected by this rounding, while the size always
4927 is and the starting offset may be. */
4929 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
4930 initial_offset_ptr is positive because locate_and_pad_parm's
4931 callers pass in the total size of args so far as
4932 initial_offset_ptr. arg_size_ptr is always positive.*/
4935 locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
4936 initial_offset_ptr, offset_ptr, arg_size_ptr,
4938 enum machine_mode passed_mode;
4940 int in_regs ATTRIBUTE_UNUSED;
4941 tree fndecl ATTRIBUTE_UNUSED;
4942 struct args_size *initial_offset_ptr;
4943 struct args_size *offset_ptr;
4944 struct args_size *arg_size_ptr;
4945 struct args_size *alignment_pad;
4949 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
4950 enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
4951 int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
4953 #ifdef REG_PARM_STACK_SPACE
4954 /* If we have found a stack parm before we reach the end of the
4955 area reserved for registers, skip that area. */
4958 int reg_parm_stack_space = 0;
4960 #ifdef MAYBE_REG_PARM_STACK_SPACE
4961 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
4963 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
4965 if (reg_parm_stack_space > 0)
4967 if (initial_offset_ptr->var)
4969 initial_offset_ptr->var
4970 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
4971 size_int (reg_parm_stack_space));
4972 initial_offset_ptr->constant = 0;
4974 else if (initial_offset_ptr->constant < reg_parm_stack_space)
4975 initial_offset_ptr->constant = reg_parm_stack_space;
4978 #endif /* REG_PARM_STACK_SPACE */
4980 arg_size_ptr->var = 0;
4981 arg_size_ptr->constant = 0;
4983 #ifdef ARGS_GROW_DOWNWARD
4984 if (initial_offset_ptr->var)
4986 offset_ptr->constant = 0;
4987 offset_ptr->var = size_binop (MINUS_EXPR, integer_zero_node,
4988 initial_offset_ptr->var);
4992 offset_ptr->constant = - initial_offset_ptr->constant;
4993 offset_ptr->var = 0;
4995 if (where_pad != none
4996 && (TREE_CODE (sizetree) != INTEGER_CST
4997 || ((TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)))
4998 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
4999 SUB_PARM_SIZE (*offset_ptr, sizetree);
5000 if (where_pad != downward)
5001 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad);
5002 if (initial_offset_ptr->var)
5004 arg_size_ptr->var = size_binop (MINUS_EXPR,
5005 size_binop (MINUS_EXPR,
5007 initial_offset_ptr->var),
5012 arg_size_ptr->constant = (- initial_offset_ptr->constant
5013 - offset_ptr->constant);
5015 #else /* !ARGS_GROW_DOWNWARD */
5016 pad_to_arg_alignment (initial_offset_ptr, boundary, alignment_pad);
5017 *offset_ptr = *initial_offset_ptr;
5019 #ifdef PUSH_ROUNDING
5020 if (passed_mode != BLKmode)
5021 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5024 /* Pad_below needs the pre-rounded size to know how much to pad below
5025 so this must be done before rounding up. */
5026 if (where_pad == downward
5027 /* However, BLKmode args passed in regs have their padding done elsewhere.
5028 The stack slot must be able to hold the entire register. */
5029 && !(in_regs && passed_mode == BLKmode))
5030 pad_below (offset_ptr, passed_mode, sizetree);
5032 if (where_pad != none
5033 && (TREE_CODE (sizetree) != INTEGER_CST
5034 || ((TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)))
5035 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5037 ADD_PARM_SIZE (*arg_size_ptr, sizetree);
5038 #endif /* ARGS_GROW_DOWNWARD */
5041 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5042 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5045 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad)
5046 struct args_size *offset_ptr;
5048 struct args_size *alignment_pad;
5050 tree save_var = NULL_TREE;
5051 HOST_WIDE_INT save_constant = 0;
5053 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5055 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5057 save_var = offset_ptr->var;
5058 save_constant = offset_ptr->constant;
5061 alignment_pad->var = NULL_TREE;
5062 alignment_pad->constant = 0;
5064 if (boundary > BITS_PER_UNIT)
5066 if (offset_ptr->var)
5069 #ifdef ARGS_GROW_DOWNWARD
5074 (ARGS_SIZE_TREE (*offset_ptr),
5075 boundary / BITS_PER_UNIT);
5076 offset_ptr->constant = 0; /*?*/
5077 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5078 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var, save_var);
5082 offset_ptr->constant =
5083 #ifdef ARGS_GROW_DOWNWARD
5084 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
5086 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
5088 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5089 alignment_pad->constant = offset_ptr->constant - save_constant;
5094 #ifndef ARGS_GROW_DOWNWARD
5096 pad_below (offset_ptr, passed_mode, sizetree)
5097 struct args_size *offset_ptr;
5098 enum machine_mode passed_mode;
5101 if (passed_mode != BLKmode)
5103 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5104 offset_ptr->constant
5105 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5106 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5107 - GET_MODE_SIZE (passed_mode));
5111 if (TREE_CODE (sizetree) != INTEGER_CST
5112 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5114 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5115 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5117 ADD_PARM_SIZE (*offset_ptr, s2);
5118 SUB_PARM_SIZE (*offset_ptr, sizetree);
5124 #ifdef ARGS_GROW_DOWNWARD
5126 round_down (value, divisor)
5130 return size_binop (MULT_EXPR,
5131 size_binop (FLOOR_DIV_EXPR, value, size_int (divisor)),
5132 size_int (divisor));
5136 /* Walk the tree of blocks describing the binding levels within a function
5137 and warn about uninitialized variables.
5138 This is done after calling flow_analysis and before global_alloc
5139 clobbers the pseudo-regs to hard regs. */
5142 uninitialized_vars_warning (block)
5145 register tree decl, sub;
5146 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5148 if (warn_uninitialized
5149 && TREE_CODE (decl) == VAR_DECL
5150 /* These warnings are unreliable for and aggregates
5151 because assigning the fields one by one can fail to convince
5152 flow.c that the entire aggregate was initialized.
5153 Unions are troublesome because members may be shorter. */
5154 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5155 && DECL_RTL (decl) != 0
5156 && GET_CODE (DECL_RTL (decl)) == REG
5157 /* Global optimizations can make it difficult to determine if a
5158 particular variable has been initialized. However, a VAR_DECL
5159 with a nonzero DECL_INITIAL had an initializer, so do not
5160 claim it is potentially uninitialized.
5162 We do not care about the actual value in DECL_INITIAL, so we do
5163 not worry that it may be a dangling pointer. */
5164 && DECL_INITIAL (decl) == NULL_TREE
5165 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5166 warning_with_decl (decl,
5167 "`%s' might be used uninitialized in this function");
5169 && TREE_CODE (decl) == VAR_DECL
5170 && DECL_RTL (decl) != 0
5171 && GET_CODE (DECL_RTL (decl)) == REG
5172 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5173 warning_with_decl (decl,
5174 "variable `%s' might be clobbered by `longjmp' or `vfork'");
5176 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5177 uninitialized_vars_warning (sub);
5180 /* Do the appropriate part of uninitialized_vars_warning
5181 but for arguments instead of local variables. */
5184 setjmp_args_warning ()
5187 for (decl = DECL_ARGUMENTS (current_function_decl);
5188 decl; decl = TREE_CHAIN (decl))
5189 if (DECL_RTL (decl) != 0
5190 && GET_CODE (DECL_RTL (decl)) == REG
5191 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5192 warning_with_decl (decl, "argument `%s' might be clobbered by `longjmp' or `vfork'");
5195 /* If this function call setjmp, put all vars into the stack
5196 unless they were declared `register'. */
5199 setjmp_protect (block)
5202 register tree decl, sub;
5203 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5204 if ((TREE_CODE (decl) == VAR_DECL
5205 || TREE_CODE (decl) == PARM_DECL)
5206 && DECL_RTL (decl) != 0
5207 && (GET_CODE (DECL_RTL (decl)) == REG
5208 || (GET_CODE (DECL_RTL (decl)) == MEM
5209 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5210 /* If this variable came from an inline function, it must be
5211 that its life doesn't overlap the setjmp. If there was a
5212 setjmp in the function, it would already be in memory. We
5213 must exclude such variable because their DECL_RTL might be
5214 set to strange things such as virtual_stack_vars_rtx. */
5215 && ! DECL_FROM_INLINE (decl)
5217 #ifdef NON_SAVING_SETJMP
5218 /* If longjmp doesn't restore the registers,
5219 don't put anything in them. */
5223 ! DECL_REGISTER (decl)))
5224 put_var_into_stack (decl);
5225 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5226 setjmp_protect (sub);
5229 /* Like the previous function, but for args instead of local variables. */
5232 setjmp_protect_args ()
5235 for (decl = DECL_ARGUMENTS (current_function_decl);
5236 decl; decl = TREE_CHAIN (decl))
5237 if ((TREE_CODE (decl) == VAR_DECL
5238 || TREE_CODE (decl) == PARM_DECL)
5239 && DECL_RTL (decl) != 0
5240 && (GET_CODE (DECL_RTL (decl)) == REG
5241 || (GET_CODE (DECL_RTL (decl)) == MEM
5242 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5244 /* If longjmp doesn't restore the registers,
5245 don't put anything in them. */
5246 #ifdef NON_SAVING_SETJMP
5250 ! DECL_REGISTER (decl)))
5251 put_var_into_stack (decl);
5254 /* Return the context-pointer register corresponding to DECL,
5255 or 0 if it does not need one. */
5258 lookup_static_chain (decl)
5261 tree context = decl_function_context (decl);
5265 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5268 /* We treat inline_function_decl as an alias for the current function
5269 because that is the inline function whose vars, types, etc.
5270 are being merged into the current function.
5271 See expand_inline_function. */
5272 if (context == current_function_decl || context == inline_function_decl)
5273 return virtual_stack_vars_rtx;
5275 for (link = context_display; link; link = TREE_CHAIN (link))
5276 if (TREE_PURPOSE (link) == context)
5277 return RTL_EXPR_RTL (TREE_VALUE (link));
5282 /* Convert a stack slot address ADDR for variable VAR
5283 (from a containing function)
5284 into an address valid in this function (using a static chain). */
5287 fix_lexical_addr (addr, var)
5292 HOST_WIDE_INT displacement;
5293 tree context = decl_function_context (var);
5294 struct function *fp;
5297 /* If this is the present function, we need not do anything. */
5298 if (context == current_function_decl || context == inline_function_decl)
5301 for (fp = outer_function_chain; fp; fp = fp->next)
5302 if (fp->decl == context)
5308 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5309 addr = XEXP (XEXP (addr, 0), 0);
5311 /* Decode given address as base reg plus displacement. */
5312 if (GET_CODE (addr) == REG)
5313 basereg = addr, displacement = 0;
5314 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5315 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5319 /* We accept vars reached via the containing function's
5320 incoming arg pointer and via its stack variables pointer. */
5321 if (basereg == fp->internal_arg_pointer)
5323 /* If reached via arg pointer, get the arg pointer value
5324 out of that function's stack frame.
5326 There are two cases: If a separate ap is needed, allocate a
5327 slot in the outer function for it and dereference it that way.
5328 This is correct even if the real ap is actually a pseudo.
5329 Otherwise, just adjust the offset from the frame pointer to
5332 #ifdef NEED_SEPARATE_AP
5335 if (fp->x_arg_pointer_save_area == 0)
5336 fp->x_arg_pointer_save_area
5337 = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, fp);
5339 addr = fix_lexical_addr (XEXP (fp->x_arg_pointer_save_area, 0), var);
5340 addr = memory_address (Pmode, addr);
5342 base = copy_to_reg (gen_rtx_MEM (Pmode, addr));
5344 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5345 base = lookup_static_chain (var);
5349 else if (basereg == virtual_stack_vars_rtx)
5351 /* This is the same code as lookup_static_chain, duplicated here to
5352 avoid an extra call to decl_function_context. */
5355 for (link = context_display; link; link = TREE_CHAIN (link))
5356 if (TREE_PURPOSE (link) == context)
5358 base = RTL_EXPR_RTL (TREE_VALUE (link));
5366 /* Use same offset, relative to appropriate static chain or argument
5368 return plus_constant (base, displacement);
5371 /* Return the address of the trampoline for entering nested fn FUNCTION.
5372 If necessary, allocate a trampoline (in the stack frame)
5373 and emit rtl to initialize its contents (at entry to this function). */
5376 trampoline_address (function)
5382 struct function *fp;
5385 /* Find an existing trampoline and return it. */
5386 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5387 if (TREE_PURPOSE (link) == function)
5389 round_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5391 for (fp = outer_function_chain; fp; fp = fp->next)
5392 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5393 if (TREE_PURPOSE (link) == function)
5395 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5397 return round_trampoline_addr (tramp);
5400 /* None exists; we must make one. */
5402 /* Find the `struct function' for the function containing FUNCTION. */
5404 fn_context = decl_function_context (function);
5405 if (fn_context != current_function_decl
5406 && fn_context != inline_function_decl)
5407 for (fp = outer_function_chain; fp; fp = fp->next)
5408 if (fp->decl == fn_context)
5411 /* Allocate run-time space for this trampoline
5412 (usually in the defining function's stack frame). */
5413 #ifdef ALLOCATE_TRAMPOLINE
5414 tramp = ALLOCATE_TRAMPOLINE (fp);
5416 /* If rounding needed, allocate extra space
5417 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5418 #ifdef TRAMPOLINE_ALIGNMENT
5419 #define TRAMPOLINE_REAL_SIZE \
5420 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5422 #define TRAMPOLINE_REAL_SIZE (TRAMPOLINE_SIZE)
5424 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5428 /* Record the trampoline for reuse and note it for later initialization
5429 by expand_function_end. */
5432 push_obstacks (fp->function_maybepermanent_obstack,
5433 fp->function_maybepermanent_obstack);
5434 rtlexp = make_node (RTL_EXPR);
5435 RTL_EXPR_RTL (rtlexp) = tramp;
5436 fp->x_trampoline_list = tree_cons (function, rtlexp,
5437 fp->x_trampoline_list);
5442 /* Make the RTL_EXPR node temporary, not momentary, so that the
5443 trampoline_list doesn't become garbage. */
5444 int momentary = suspend_momentary ();
5445 rtlexp = make_node (RTL_EXPR);
5446 resume_momentary (momentary);
5448 RTL_EXPR_RTL (rtlexp) = tramp;
5449 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5452 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5453 return round_trampoline_addr (tramp);
5456 /* Given a trampoline address,
5457 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5460 round_trampoline_addr (tramp)
5463 #ifdef TRAMPOLINE_ALIGNMENT
5464 /* Round address up to desired boundary. */
5465 rtx temp = gen_reg_rtx (Pmode);
5466 temp = expand_binop (Pmode, add_optab, tramp,
5467 GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1),
5468 temp, 0, OPTAB_LIB_WIDEN);
5469 tramp = expand_binop (Pmode, and_optab, temp,
5470 GEN_INT (- TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT),
5471 temp, 0, OPTAB_LIB_WIDEN);
5476 /* The functions identify_blocks and reorder_blocks provide a way to
5477 reorder the tree of BLOCK nodes, for optimizers that reshuffle or
5478 duplicate portions of the RTL code. Call identify_blocks before
5479 changing the RTL, and call reorder_blocks after. */
5481 /* Put all this function's BLOCK nodes including those that are chained
5482 onto the first block into a vector, and return it.
5483 Also store in each NOTE for the beginning or end of a block
5484 the index of that block in the vector.
5485 The arguments are BLOCK, the chain of top-level blocks of the function,
5486 and INSNS, the insn chain of the function. */
5489 identify_blocks (block, insns)
5497 int current_block_number = 1;
5503 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5504 depth-first order. */
5505 n_blocks = all_blocks (block, 0);
5506 block_vector = (tree *) xmalloc (n_blocks * sizeof (tree));
5507 all_blocks (block, block_vector);
5509 block_stack = (tree *) xmalloc (n_blocks * sizeof (tree));
5511 for (insn = insns; insn; insn = NEXT_INSN (insn))
5512 if (GET_CODE (insn) == NOTE)
5514 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5518 /* If there are more block notes than BLOCKs, something
5520 if (current_block_number == n_blocks)
5523 b = block_vector[current_block_number++];
5524 NOTE_BLOCK (insn) = b;
5525 block_stack[depth++] = b;
5527 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5530 /* There are more NOTE_INSN_BLOCK_ENDs that
5531 NOTE_INSN_BLOCK_BEGs. Something is badly wrong. */
5534 NOTE_BLOCK (insn) = block_stack[--depth];
5538 /* In whole-function mode, we might not have seen the whole function
5539 yet, so we might not use up all the blocks. */
5540 if (n_blocks != current_block_number
5541 && !cfun->x_whole_function_mode_p)
5544 free (block_vector);
5548 /* Given a revised instruction chain, rebuild the tree structure of
5549 BLOCK nodes to correspond to the new order of RTL. The new block
5550 tree is inserted below TOP_BLOCK. Returns the current top-level
5554 reorder_blocks (block, insns)
5558 tree current_block = block;
5561 if (block == NULL_TREE)
5564 /* Prune the old trees away, so that it doesn't get in the way. */
5565 BLOCK_SUBBLOCKS (current_block) = 0;
5566 BLOCK_CHAIN (current_block) = 0;
5568 for (insn = insns; insn; insn = NEXT_INSN (insn))
5569 if (GET_CODE (insn) == NOTE)
5571 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5573 tree block = NOTE_BLOCK (insn);
5574 /* If we have seen this block before, copy it. */
5575 if (TREE_ASM_WRITTEN (block))
5576 block = copy_node (block);
5577 BLOCK_SUBBLOCKS (block) = 0;
5578 TREE_ASM_WRITTEN (block) = 1;
5579 BLOCK_SUPERCONTEXT (block) = current_block;
5580 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
5581 BLOCK_SUBBLOCKS (current_block) = block;
5582 current_block = block;
5584 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5586 BLOCK_SUBBLOCKS (current_block)
5587 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5588 current_block = BLOCK_SUPERCONTEXT (current_block);
5592 BLOCK_SUBBLOCKS (current_block)
5593 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5594 return current_block;
5597 /* Reverse the order of elements in the chain T of blocks,
5598 and return the new head of the chain (old last element). */
5604 register tree prev = 0, decl, next;
5605 for (decl = t; decl; decl = next)
5607 next = BLOCK_CHAIN (decl);
5608 BLOCK_CHAIN (decl) = prev;
5614 /* Count the subblocks of the list starting with BLOCK, and list them
5615 all into the vector VECTOR. Also clear TREE_ASM_WRITTEN in all
5619 all_blocks (block, vector)
5627 TREE_ASM_WRITTEN (block) = 0;
5629 /* Record this block. */
5631 vector[n_blocks] = block;
5635 /* Record the subblocks, and their subblocks... */
5636 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
5637 vector ? vector + n_blocks : 0);
5638 block = BLOCK_CHAIN (block);
5644 /* Allocate a function structure and reset its contents to the defaults. */
5646 prepare_function_start ()
5648 cfun = (struct function *) xcalloc (1, sizeof (struct function));
5650 init_stmt_for_function ();
5651 init_eh_for_function ();
5653 cse_not_expected = ! optimize;
5655 /* Caller save not needed yet. */
5656 caller_save_needed = 0;
5658 /* No stack slots have been made yet. */
5659 stack_slot_list = 0;
5661 current_function_has_nonlocal_label = 0;
5662 current_function_has_nonlocal_goto = 0;
5664 /* There is no stack slot for handling nonlocal gotos. */
5665 nonlocal_goto_handler_slots = 0;
5666 nonlocal_goto_stack_level = 0;
5668 /* No labels have been declared for nonlocal use. */
5669 nonlocal_labels = 0;
5670 nonlocal_goto_handler_labels = 0;
5672 /* No function calls so far in this function. */
5673 function_call_count = 0;
5675 /* No parm regs have been allocated.
5676 (This is important for output_inline_function.) */
5677 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
5679 /* Initialize the RTL mechanism. */
5682 /* Initialize the queue of pending postincrement and postdecrements,
5683 and some other info in expr.c. */
5686 /* We haven't done register allocation yet. */
5689 init_varasm_status (cfun);
5691 /* Clear out data used for inlining. */
5692 cfun->inlinable = 0;
5693 cfun->original_decl_initial = 0;
5694 cfun->original_arg_vector = 0;
5696 cfun->stack_alignment_needed = 0;
5697 #ifdef STACK_BOUNDARY
5698 cfun->preferred_stack_boundary = STACK_BOUNDARY;
5701 /* Set if a call to setjmp is seen. */
5702 current_function_calls_setjmp = 0;
5704 /* Set if a call to longjmp is seen. */
5705 current_function_calls_longjmp = 0;
5707 current_function_calls_alloca = 0;
5708 current_function_contains_functions = 0;
5709 current_function_is_leaf = 0;
5710 current_function_sp_is_unchanging = 0;
5711 current_function_uses_only_leaf_regs = 0;
5712 current_function_has_computed_jump = 0;
5713 current_function_is_thunk = 0;
5715 current_function_returns_pcc_struct = 0;
5716 current_function_returns_struct = 0;
5717 current_function_epilogue_delay_list = 0;
5718 current_function_uses_const_pool = 0;
5719 current_function_uses_pic_offset_table = 0;
5720 current_function_cannot_inline = 0;
5722 /* We have not yet needed to make a label to jump to for tail-recursion. */
5723 tail_recursion_label = 0;
5725 /* We haven't had a need to make a save area for ap yet. */
5726 arg_pointer_save_area = 0;
5728 /* No stack slots allocated yet. */
5731 /* No SAVE_EXPRs in this function yet. */
5734 /* No RTL_EXPRs in this function yet. */
5737 /* Set up to allocate temporaries. */
5740 /* Indicate that we need to distinguish between the return value of the
5741 present function and the return value of a function being called. */
5742 rtx_equal_function_value_matters = 1;
5744 /* Indicate that we have not instantiated virtual registers yet. */
5745 virtuals_instantiated = 0;
5747 /* Indicate we have no need of a frame pointer yet. */
5748 frame_pointer_needed = 0;
5750 /* By default assume not varargs or stdarg. */
5751 current_function_varargs = 0;
5752 current_function_stdarg = 0;
5754 /* We haven't made any trampolines for this function yet. */
5755 trampoline_list = 0;
5757 init_pending_stack_adjust ();
5758 inhibit_defer_pop = 0;
5760 current_function_outgoing_args_size = 0;
5762 if (init_lang_status)
5763 (*init_lang_status) (cfun);
5764 if (init_machine_status)
5765 (*init_machine_status) (cfun);
5768 /* Initialize the rtl expansion mechanism so that we can do simple things
5769 like generate sequences. This is used to provide a context during global
5770 initialization of some passes. */
5772 init_dummy_function_start ()
5774 prepare_function_start ();
5777 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
5778 and initialize static variables for generating RTL for the statements
5782 init_function_start (subr, filename, line)
5787 prepare_function_start ();
5789 /* Remember this function for later. */
5790 cfun->next_global = all_functions;
5791 all_functions = cfun;
5793 current_function_name = (*decl_printable_name) (subr, 2);
5796 /* Nonzero if this is a nested function that uses a static chain. */
5798 current_function_needs_context
5799 = (decl_function_context (current_function_decl) != 0
5800 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
5802 /* Within function body, compute a type's size as soon it is laid out. */
5803 immediate_size_expand++;
5805 /* Prevent ever trying to delete the first instruction of a function.
5806 Also tell final how to output a linenum before the function prologue.
5807 Note linenums could be missing, e.g. when compiling a Java .class file. */
5809 emit_line_note (filename, line);
5811 /* Make sure first insn is a note even if we don't want linenums.
5812 This makes sure the first insn will never be deleted.
5813 Also, final expects a note to appear there. */
5814 emit_note (NULL_PTR, NOTE_INSN_DELETED);
5816 /* Set flags used by final.c. */
5817 if (aggregate_value_p (DECL_RESULT (subr)))
5819 #ifdef PCC_STATIC_STRUCT_RETURN
5820 current_function_returns_pcc_struct = 1;
5822 current_function_returns_struct = 1;
5825 /* Warn if this value is an aggregate type,
5826 regardless of which calling convention we are using for it. */
5827 if (warn_aggregate_return
5828 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
5829 warning ("function returns an aggregate");
5831 current_function_returns_pointer
5832 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
5835 /* Make sure all values used by the optimization passes have sane
5838 init_function_for_compilation ()
5841 /* No prologue/epilogue insns yet. */
5842 prologue = epilogue = 0;
5845 /* Indicate that the current function uses extra args
5846 not explicitly mentioned in the argument list in any fashion. */
5851 current_function_varargs = 1;
5854 /* Expand a call to __main at the beginning of a possible main function. */
5856 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
5857 #undef HAS_INIT_SECTION
5858 #define HAS_INIT_SECTION
5862 expand_main_function ()
5864 #if !defined (HAS_INIT_SECTION)
5865 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, NAME__MAIN), 0,
5867 #endif /* not HAS_INIT_SECTION */
5870 extern struct obstack permanent_obstack;
5872 /* Start the RTL for a new function, and set variables used for
5874 SUBR is the FUNCTION_DECL node.
5875 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
5876 the function's parameters, which must be run at any return statement. */
5879 expand_function_start (subr, parms_have_cleanups)
5881 int parms_have_cleanups;
5884 rtx last_ptr = NULL_RTX;
5886 /* Make sure volatile mem refs aren't considered
5887 valid operands of arithmetic insns. */
5888 init_recog_no_volatile ();
5890 /* Set this before generating any memory accesses. */
5891 current_function_check_memory_usage
5892 = (flag_check_memory_usage
5893 && ! DECL_NO_CHECK_MEMORY_USAGE (current_function_decl));
5895 current_function_instrument_entry_exit
5896 = (flag_instrument_function_entry_exit
5897 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
5899 current_function_limit_stack
5900 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
5902 /* If function gets a static chain arg, store it in the stack frame.
5903 Do this first, so it gets the first stack slot offset. */
5904 if (current_function_needs_context)
5906 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
5908 /* Delay copying static chain if it is not a register to avoid
5909 conflicts with regs used for parameters. */
5910 if (! SMALL_REGISTER_CLASSES
5911 || GET_CODE (static_chain_incoming_rtx) == REG)
5912 emit_move_insn (last_ptr, static_chain_incoming_rtx);
5915 /* If the parameters of this function need cleaning up, get a label
5916 for the beginning of the code which executes those cleanups. This must
5917 be done before doing anything with return_label. */
5918 if (parms_have_cleanups)
5919 cleanup_label = gen_label_rtx ();
5923 /* Make the label for return statements to jump to, if this machine
5924 does not have a one-instruction return and uses an epilogue,
5925 or if it returns a structure, or if it has parm cleanups. */
5927 if (cleanup_label == 0 && HAVE_return
5928 && ! current_function_instrument_entry_exit
5929 && ! current_function_returns_pcc_struct
5930 && ! (current_function_returns_struct && ! optimize))
5933 return_label = gen_label_rtx ();
5935 return_label = gen_label_rtx ();
5938 /* Initialize rtx used to return the value. */
5939 /* Do this before assign_parms so that we copy the struct value address
5940 before any library calls that assign parms might generate. */
5942 /* Decide whether to return the value in memory or in a register. */
5943 if (aggregate_value_p (DECL_RESULT (subr)))
5945 /* Returning something that won't go in a register. */
5946 register rtx value_address = 0;
5948 #ifdef PCC_STATIC_STRUCT_RETURN
5949 if (current_function_returns_pcc_struct)
5951 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
5952 value_address = assemble_static_space (size);
5957 /* Expect to be passed the address of a place to store the value.
5958 If it is passed as an argument, assign_parms will take care of
5960 if (struct_value_incoming_rtx)
5962 value_address = gen_reg_rtx (Pmode);
5963 emit_move_insn (value_address, struct_value_incoming_rtx);
5968 DECL_RTL (DECL_RESULT (subr))
5969 = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
5970 MEM_SET_IN_STRUCT_P (DECL_RTL (DECL_RESULT (subr)),
5971 AGGREGATE_TYPE_P (TREE_TYPE
5976 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
5977 /* If return mode is void, this decl rtl should not be used. */
5978 DECL_RTL (DECL_RESULT (subr)) = 0;
5979 else if (parms_have_cleanups || current_function_instrument_entry_exit)
5981 /* If function will end with cleanup code for parms,
5982 compute the return values into a pseudo reg,
5983 which we will copy into the true return register
5984 after the cleanups are done. */
5986 enum machine_mode mode = DECL_MODE (DECL_RESULT (subr));
5988 #ifdef PROMOTE_FUNCTION_RETURN
5989 tree type = TREE_TYPE (DECL_RESULT (subr));
5990 int unsignedp = TREE_UNSIGNED (type);
5992 mode = promote_mode (type, mode, &unsignedp, 1);
5995 DECL_RTL (DECL_RESULT (subr)) = gen_reg_rtx (mode);
5998 /* Scalar, returned in a register. */
6000 #ifdef FUNCTION_OUTGOING_VALUE
6001 DECL_RTL (DECL_RESULT (subr))
6002 = FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (subr)), subr);
6004 DECL_RTL (DECL_RESULT (subr))
6005 = FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (subr)), subr);
6008 /* Mark this reg as the function's return value. */
6009 if (GET_CODE (DECL_RTL (DECL_RESULT (subr))) == REG)
6011 REG_FUNCTION_VALUE_P (DECL_RTL (DECL_RESULT (subr))) = 1;
6012 /* Needed because we may need to move this to memory
6013 in case it's a named return value whose address is taken. */
6014 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6018 /* Initialize rtx for parameters and local variables.
6019 In some cases this requires emitting insns. */
6021 assign_parms (subr);
6023 /* Copy the static chain now if it wasn't a register. The delay is to
6024 avoid conflicts with the parameter passing registers. */
6026 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6027 if (GET_CODE (static_chain_incoming_rtx) != REG)
6028 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6030 /* The following was moved from init_function_start.
6031 The move is supposed to make sdb output more accurate. */
6032 /* Indicate the beginning of the function body,
6033 as opposed to parm setup. */
6034 emit_note (NULL_PTR, NOTE_INSN_FUNCTION_BEG);
6036 if (GET_CODE (get_last_insn ()) != NOTE)
6037 emit_note (NULL_PTR, NOTE_INSN_DELETED);
6038 parm_birth_insn = get_last_insn ();
6040 context_display = 0;
6041 if (current_function_needs_context)
6043 /* Fetch static chain values for containing functions. */
6044 tem = decl_function_context (current_function_decl);
6045 /* Copy the static chain pointer into a pseudo. If we have
6046 small register classes, copy the value from memory if
6047 static_chain_incoming_rtx is a REG. */
6050 /* If the static chain originally came in a register, put it back
6051 there, then move it out in the next insn. The reason for
6052 this peculiar code is to satisfy function integration. */
6053 if (SMALL_REGISTER_CLASSES
6054 && GET_CODE (static_chain_incoming_rtx) == REG)
6055 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6056 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6061 tree rtlexp = make_node (RTL_EXPR);
6063 RTL_EXPR_RTL (rtlexp) = last_ptr;
6064 context_display = tree_cons (tem, rtlexp, context_display);
6065 tem = decl_function_context (tem);
6068 /* Chain thru stack frames, assuming pointer to next lexical frame
6069 is found at the place we always store it. */
6070 #ifdef FRAME_GROWS_DOWNWARD
6071 last_ptr = plus_constant (last_ptr, - GET_MODE_SIZE (Pmode));
6073 last_ptr = copy_to_reg (gen_rtx_MEM (Pmode,
6074 memory_address (Pmode,
6077 /* If we are not optimizing, ensure that we know that this
6078 piece of context is live over the entire function. */
6080 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6085 if (current_function_instrument_entry_exit)
6087 rtx fun = DECL_RTL (current_function_decl);
6088 if (GET_CODE (fun) == MEM)
6089 fun = XEXP (fun, 0);
6092 emit_library_call (profile_function_entry_libfunc, 0, VOIDmode, 2,
6094 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6096 hard_frame_pointer_rtx),
6100 /* After the display initializations is where the tail-recursion label
6101 should go, if we end up needing one. Ensure we have a NOTE here
6102 since some things (like trampolines) get placed before this. */
6103 tail_recursion_reentry = emit_note (NULL_PTR, NOTE_INSN_DELETED);
6105 /* Evaluate now the sizes of any types declared among the arguments. */
6106 for (tem = nreverse (get_pending_sizes ()); tem; tem = TREE_CHAIN (tem))
6108 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode,
6109 EXPAND_MEMORY_USE_BAD);
6110 /* Flush the queue in case this parameter declaration has
6115 /* Make sure there is a line number after the function entry setup code. */
6116 force_next_line_note ();
6119 /* Undo the effects of init_dummy_function_start. */
6121 expand_dummy_function_end ()
6123 /* End any sequences that failed to be closed due to syntax errors. */
6124 while (in_sequence_p ())
6127 /* Outside function body, can't compute type's actual size
6128 until next function's body starts. */
6130 free_after_parsing (cfun);
6131 free_after_compilation (cfun);
6136 /* Call DOIT for each hard register used as a return value from
6137 the current function. */
6140 diddle_return_value (doit, arg)
6141 void (*doit) PARAMS ((rtx, void *));
6144 rtx outgoing = current_function_return_rtx;
6149 if (GET_CODE (outgoing) == REG
6150 && REGNO (outgoing) >= FIRST_PSEUDO_REGISTER)
6152 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
6153 #ifdef FUNCTION_OUTGOING_VALUE
6154 outgoing = FUNCTION_OUTGOING_VALUE (type, current_function_decl);
6156 outgoing = FUNCTION_VALUE (type, current_function_decl);
6158 /* If this is a BLKmode structure being returned in registers, then use
6159 the mode computed in expand_return. */
6160 if (GET_MODE (outgoing) == BLKmode)
6162 GET_MODE (DECL_RTL (DECL_RESULT (current_function_decl))));
6165 if (GET_CODE (outgoing) == REG)
6166 (*doit) (outgoing, arg);
6167 else if (GET_CODE (outgoing) == PARALLEL)
6171 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6173 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6175 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6182 do_clobber_return_reg (reg, arg)
6184 void *arg ATTRIBUTE_UNUSED;
6186 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6190 clobber_return_register ()
6192 diddle_return_value (do_clobber_return_reg, NULL);
6196 do_use_return_reg (reg, arg)
6198 void *arg ATTRIBUTE_UNUSED;
6200 emit_insn (gen_rtx_USE (VOIDmode, reg));
6204 use_return_register ()
6206 diddle_return_value (do_use_return_reg, NULL);
6209 /* Generate RTL for the end of the current function.
6210 FILENAME and LINE are the current position in the source file.
6212 It is up to language-specific callers to do cleanups for parameters--
6213 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
6216 expand_function_end (filename, line, end_bindings)
6223 #ifdef TRAMPOLINE_TEMPLATE
6224 static rtx initial_trampoline;
6227 finish_expr_for_function ();
6229 #ifdef NON_SAVING_SETJMP
6230 /* Don't put any variables in registers if we call setjmp
6231 on a machine that fails to restore the registers. */
6232 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6234 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6235 setjmp_protect (DECL_INITIAL (current_function_decl));
6237 setjmp_protect_args ();
6241 /* Save the argument pointer if a save area was made for it. */
6242 if (arg_pointer_save_area)
6244 /* arg_pointer_save_area may not be a valid memory address, so we
6245 have to check it and fix it if necessary. */
6248 emit_move_insn (validize_mem (arg_pointer_save_area),
6249 virtual_incoming_args_rtx);
6250 seq = gen_sequence ();
6252 emit_insn_before (seq, tail_recursion_reentry);
6255 /* Initialize any trampolines required by this function. */
6256 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6258 tree function = TREE_PURPOSE (link);
6259 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6260 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6261 #ifdef TRAMPOLINE_TEMPLATE
6266 #ifdef TRAMPOLINE_TEMPLATE
6267 /* First make sure this compilation has a template for
6268 initializing trampolines. */
6269 if (initial_trampoline == 0)
6271 end_temporary_allocation ();
6273 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6274 resume_temporary_allocation ();
6276 ggc_add_rtx_root (&initial_trampoline, 1);
6280 /* Generate insns to initialize the trampoline. */
6282 tramp = round_trampoline_addr (XEXP (tramp, 0));
6283 #ifdef TRAMPOLINE_TEMPLATE
6284 blktramp = change_address (initial_trampoline, BLKmode, tramp);
6285 emit_block_move (blktramp, initial_trampoline,
6286 GEN_INT (TRAMPOLINE_SIZE),
6287 TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
6289 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6293 /* Put those insns at entry to the containing function (this one). */
6294 emit_insns_before (seq, tail_recursion_reentry);
6297 /* If we are doing stack checking and this function makes calls,
6298 do a stack probe at the start of the function to ensure we have enough
6299 space for another stack frame. */
6300 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6304 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6305 if (GET_CODE (insn) == CALL_INSN)
6308 probe_stack_range (STACK_CHECK_PROTECT,
6309 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6312 emit_insns_before (seq, tail_recursion_reentry);
6317 /* Warn about unused parms if extra warnings were specified. */
6318 if (warn_unused && extra_warnings)
6322 for (decl = DECL_ARGUMENTS (current_function_decl);
6323 decl; decl = TREE_CHAIN (decl))
6324 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6325 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6326 warning_with_decl (decl, "unused parameter `%s'");
6329 /* Delete handlers for nonlocal gotos if nothing uses them. */
6330 if (nonlocal_goto_handler_slots != 0
6331 && ! current_function_has_nonlocal_label)
6334 /* End any sequences that failed to be closed due to syntax errors. */
6335 while (in_sequence_p ())
6338 /* Outside function body, can't compute type's actual size
6339 until next function's body starts. */
6340 immediate_size_expand--;
6342 clear_pending_stack_adjust ();
6343 do_pending_stack_adjust ();
6345 /* Mark the end of the function body.
6346 If control reaches this insn, the function can drop through
6347 without returning a value. */
6348 emit_note (NULL_PTR, NOTE_INSN_FUNCTION_END);
6350 /* Must mark the last line number note in the function, so that the test
6351 coverage code can avoid counting the last line twice. This just tells
6352 the code to ignore the immediately following line note, since there
6353 already exists a copy of this note somewhere above. This line number
6354 note is still needed for debugging though, so we can't delete it. */
6355 if (flag_test_coverage)
6356 emit_note (NULL_PTR, NOTE_REPEATED_LINE_NUMBER);
6358 /* Output a linenumber for the end of the function.
6359 SDB depends on this. */
6360 emit_line_note_force (filename, line);
6362 /* Output the label for the actual return from the function,
6363 if one is expected. This happens either because a function epilogue
6364 is used instead of a return instruction, or because a return was done
6365 with a goto in order to run local cleanups, or because of pcc-style
6366 structure returning. */
6370 /* Before the return label, clobber the return registers so that
6371 they are not propogated live to the rest of the function. This
6372 can only happen with functions that drop through; if there had
6373 been a return statement, there would have either been a return
6374 rtx, or a jump to the return label. */
6375 clobber_return_register ();
6377 emit_label (return_label);
6380 /* C++ uses this. */
6382 expand_end_bindings (0, 0, 0);
6384 /* Now handle any leftover exception regions that may have been
6385 created for the parameters. */
6387 rtx last = get_last_insn ();
6390 expand_leftover_cleanups ();
6392 /* If there are any catch_clauses remaining, output them now. */
6393 emit_insns (catch_clauses);
6394 catch_clauses = NULL_RTX;
6395 /* If the above emitted any code, may sure we jump around it. */
6396 if (last != get_last_insn ())
6398 label = gen_label_rtx ();
6399 last = emit_jump_insn_after (gen_jump (label), last);
6400 last = emit_barrier_after (last);
6405 if (current_function_instrument_entry_exit)
6407 rtx fun = DECL_RTL (current_function_decl);
6408 if (GET_CODE (fun) == MEM)
6409 fun = XEXP (fun, 0);
6412 emit_library_call (profile_function_exit_libfunc, 0, VOIDmode, 2,
6414 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6416 hard_frame_pointer_rtx),
6420 /* If we had calls to alloca, and this machine needs
6421 an accurate stack pointer to exit the function,
6422 insert some code to save and restore the stack pointer. */
6423 #ifdef EXIT_IGNORE_STACK
6424 if (! EXIT_IGNORE_STACK)
6426 if (current_function_calls_alloca)
6430 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
6431 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
6434 /* If scalar return value was computed in a pseudo-reg,
6435 copy that to the hard return register. */
6436 if (DECL_RTL (DECL_RESULT (current_function_decl)) != 0
6437 && GET_CODE (DECL_RTL (DECL_RESULT (current_function_decl))) == REG
6438 && (REGNO (DECL_RTL (DECL_RESULT (current_function_decl)))
6439 >= FIRST_PSEUDO_REGISTER))
6441 rtx real_decl_result;
6443 #ifdef FUNCTION_OUTGOING_VALUE
6445 = FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl)),
6446 current_function_decl);
6449 = FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl)),
6450 current_function_decl);
6452 REG_FUNCTION_VALUE_P (real_decl_result) = 1;
6453 /* If this is a BLKmode structure being returned in registers, then use
6454 the mode computed in expand_return. */
6455 if (GET_MODE (real_decl_result) == BLKmode)
6456 PUT_MODE (real_decl_result,
6457 GET_MODE (DECL_RTL (DECL_RESULT (current_function_decl))));
6458 emit_move_insn (real_decl_result,
6459 DECL_RTL (DECL_RESULT (current_function_decl)));
6461 /* The delay slot scheduler assumes that current_function_return_rtx
6462 holds the hard register containing the return value, not a temporary
6464 current_function_return_rtx = real_decl_result;
6467 /* If returning a structure, arrange to return the address of the value
6468 in a place where debuggers expect to find it.
6470 If returning a structure PCC style,
6471 the caller also depends on this value.
6472 And current_function_returns_pcc_struct is not necessarily set. */
6473 if (current_function_returns_struct
6474 || current_function_returns_pcc_struct)
6476 rtx value_address = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
6477 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
6478 #ifdef FUNCTION_OUTGOING_VALUE
6480 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
6481 current_function_decl);
6484 = FUNCTION_VALUE (build_pointer_type (type),
6485 current_function_decl);
6488 /* Mark this as a function return value so integrate will delete the
6489 assignment and USE below when inlining this function. */
6490 REG_FUNCTION_VALUE_P (outgoing) = 1;
6492 emit_move_insn (outgoing, value_address);
6495 /* ??? This should no longer be necessary since stupid is no longer with
6496 us, but there are some parts of the compiler (eg reload_combine, and
6497 sh mach_dep_reorg) that still try and compute their own lifetime info
6498 instead of using the general framework. */
6499 use_return_register ();
6501 /* If this is an implementation of __throw, do what's necessary to
6502 communicate between __builtin_eh_return and the epilogue. */
6503 expand_eh_return ();
6505 /* Output a return insn if we are using one.
6506 Otherwise, let the rtl chain end here, to drop through
6507 into the epilogue. */
6512 emit_jump_insn (gen_return ());
6517 /* Fix up any gotos that jumped out to the outermost
6518 binding level of the function.
6519 Must follow emitting RETURN_LABEL. */
6521 /* If you have any cleanups to do at this point,
6522 and they need to create temporary variables,
6523 then you will lose. */
6524 expand_fixups (get_insns ());
6527 /* Create an array that records the INSN_UIDs of INSNS (either a sequence
6528 or a single insn). */
6531 record_insns (insns)
6536 if (GET_CODE (insns) == SEQUENCE)
6538 int len = XVECLEN (insns, 0);
6539 vec = (int *) oballoc ((len + 1) * sizeof (int));
6542 vec[len] = INSN_UID (XVECEXP (insns, 0, len));
6546 vec = (int *) oballoc (2 * sizeof (int));
6547 vec[0] = INSN_UID (insns);
6553 /* Determine how many INSN_UIDs in VEC are part of INSN. */
6556 contains (insn, vec)
6562 if (GET_CODE (insn) == INSN
6563 && GET_CODE (PATTERN (insn)) == SEQUENCE)
6566 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
6567 for (j = 0; vec[j]; j++)
6568 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == vec[j])
6574 for (j = 0; vec[j]; j++)
6575 if (INSN_UID (insn) == vec[j])
6582 prologue_epilogue_contains (insn)
6585 if (prologue && contains (insn, prologue))
6587 if (epilogue && contains (insn, epilogue))
6593 /* Insert gen_return at the end of block BB. This also means updating
6594 block_for_insn appropriately. */
6597 emit_return_into_block (bb)
6602 end = emit_jump_insn_after (gen_return (), bb->end);
6603 p = NEXT_INSN (bb->end);
6606 set_block_for_insn (p, bb);
6613 #endif /* HAVE_return */
6615 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
6616 this into place with notes indicating where the prologue ends and where
6617 the epilogue begins. Update the basic block information when possible. */
6620 thread_prologue_and_epilogue_insns (f)
6621 rtx f ATTRIBUTE_UNUSED;
6627 #ifdef HAVE_prologue
6633 seq = gen_prologue();
6636 /* Retain a map of the prologue insns. */
6637 if (GET_CODE (seq) != SEQUENCE)
6639 prologue = record_insns (seq);
6640 emit_note (NULL, NOTE_INSN_PROLOGUE_END);
6642 /* GDB handles `break f' by setting a breakpoint on the first
6643 line note *after* the prologue. That means that we should
6644 insert a line note here; otherwise, if the next line note
6645 comes part way into the next block, GDB will skip all the way
6647 insn = next_nonnote_insn (f);
6650 if (GET_CODE (insn) == NOTE
6651 && NOTE_LINE_NUMBER (insn) >= 0)
6653 emit_line_note_force (NOTE_SOURCE_FILE (insn),
6654 NOTE_LINE_NUMBER (insn));
6658 insn = PREV_INSN (insn);
6661 seq = gen_sequence ();
6664 /* If optimization is off, and perhaps in an empty function,
6665 the entry block will have no successors. */
6666 if (ENTRY_BLOCK_PTR->succ)
6668 /* Can't deal with multiple successsors of the entry block. */
6669 if (ENTRY_BLOCK_PTR->succ->succ_next)
6672 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
6676 emit_insn_after (seq, f);
6680 /* If the exit block has no non-fake predecessors, we don't need
6682 for (e = EXIT_BLOCK_PTR->pred; e ; e = e->pred_next)
6683 if ((e->flags & EDGE_FAKE) == 0)
6689 if (optimize && HAVE_return)
6691 /* If we're allowed to generate a simple return instruction,
6692 then by definition we don't need a full epilogue. Examine
6693 the block that falls through to EXIT. If it does not
6694 contain any code, examine its predecessors and try to
6695 emit (conditional) return instructions. */
6701 for (e = EXIT_BLOCK_PTR->pred; e ; e = e->pred_next)
6702 if (e->flags & EDGE_FALLTHRU)
6708 /* Verify that there are no active instructions in the last block. */
6710 while (label && GET_CODE (label) != CODE_LABEL)
6712 if (active_insn_p (label))
6714 label = PREV_INSN (label);
6717 if (last->head == label && GET_CODE (label) == CODE_LABEL)
6719 for (e = last->pred; e ; e = e_next)
6721 basic_block bb = e->src;
6724 e_next = e->pred_next;
6725 if (bb == ENTRY_BLOCK_PTR)
6729 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
6732 /* If we have an unconditional jump, we can replace that
6733 with a simple return instruction. */
6734 if (simplejump_p (jump))
6736 emit_return_into_block (bb);
6737 flow_delete_insn (jump);
6740 /* If we have a conditional jump, we can try to replace
6741 that with a conditional return instruction. */
6742 else if (condjump_p (jump))
6746 ret = SET_SRC (PATTERN (jump));
6747 if (GET_CODE (XEXP (ret, 1)) == LABEL_REF)
6748 loc = &XEXP (ret, 1);
6750 loc = &XEXP (ret, 2);
6751 ret = gen_rtx_RETURN (VOIDmode);
6753 if (! validate_change (jump, loc, ret, 0))
6755 if (JUMP_LABEL (jump))
6756 LABEL_NUSES (JUMP_LABEL (jump))--;
6758 /* If this block has only one successor, it both jumps
6759 and falls through to the fallthru block, so we can't
6761 if (bb->succ->succ_next == NULL)
6767 /* Fix up the CFG for the successful change we just made. */
6769 make_edge (NULL, bb, EXIT_BLOCK_PTR, 0);
6772 /* Emit a return insn for the exit fallthru block. Whether
6773 this is still reachable will be determined later. */
6775 emit_barrier_after (last->end);
6776 emit_return_into_block (last);
6780 /* The exit block wasn't empty. We have to use insert_insn_on_edge,
6781 as it may be the exit block can go elsewhere as well
6784 emit_jump_insn (gen_return ());
6785 seq = gen_sequence ();
6787 insert_insn_on_edge (seq, e);
6793 #ifdef HAVE_epilogue
6796 /* Find the edge that falls through to EXIT. Other edges may exist
6797 due to RETURN instructions, but those don't need epilogues.
6798 There really shouldn't be a mixture -- either all should have
6799 been converted or none, however... */
6801 for (e = EXIT_BLOCK_PTR->pred; e ; e = e->pred_next)
6802 if (e->flags & EDGE_FALLTHRU)
6808 emit_note (NULL, NOTE_INSN_EPILOGUE_BEG);
6810 seq = gen_epilogue ();
6811 emit_jump_insn (seq);
6813 /* Retain a map of the epilogue insns. */
6814 if (GET_CODE (seq) != SEQUENCE)
6816 epilogue = record_insns (seq);
6818 seq = gen_sequence ();
6821 insert_insn_on_edge (seq, e);
6828 commit_edge_insertions ();
6831 /* Reposition the prologue-end and epilogue-begin notes after instruction
6832 scheduling and delayed branch scheduling. */
6835 reposition_prologue_and_epilogue_notes (f)
6836 rtx f ATTRIBUTE_UNUSED;
6838 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
6839 /* Reposition the prologue and epilogue notes. */
6846 register rtx insn, note = 0;
6848 /* Scan from the beginning until we reach the last prologue insn.
6849 We apparently can't depend on basic_block_{head,end} after
6851 for (len = 0; prologue[len]; len++)
6853 for (insn = f; len && insn; insn = NEXT_INSN (insn))
6855 if (GET_CODE (insn) == NOTE)
6857 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
6860 else if ((len -= contains (insn, prologue)) == 0)
6863 /* Find the prologue-end note if we haven't already, and
6864 move it to just after the last prologue insn. */
6867 for (note = insn; (note = NEXT_INSN (note));)
6868 if (GET_CODE (note) == NOTE
6869 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
6873 next = NEXT_INSN (note);
6875 /* Whether or not we can depend on BLOCK_HEAD,
6876 attempt to keep it up-to-date. */
6877 if (BLOCK_HEAD (0) == note)
6878 BLOCK_HEAD (0) = next;
6881 add_insn_after (note, insn);
6888 register rtx insn, note = 0;
6890 /* Scan from the end until we reach the first epilogue insn.
6891 We apparently can't depend on basic_block_{head,end} after
6893 for (len = 0; epilogue[len]; len++)
6895 for (insn = get_last_insn (); len && insn; insn = PREV_INSN (insn))
6897 if (GET_CODE (insn) == NOTE)
6899 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
6902 else if ((len -= contains (insn, epilogue)) == 0)
6904 /* Find the epilogue-begin note if we haven't already, and
6905 move it to just before the first epilogue insn. */
6908 for (note = insn; (note = PREV_INSN (note));)
6909 if (GET_CODE (note) == NOTE
6910 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
6914 /* Whether or not we can depend on BLOCK_HEAD,
6915 attempt to keep it up-to-date. */
6917 && BLOCK_HEAD (n_basic_blocks-1) == insn)
6918 BLOCK_HEAD (n_basic_blocks-1) = note;
6921 add_insn_before (note, insn);
6926 #endif /* HAVE_prologue or HAVE_epilogue */
6929 /* Mark T for GC. */
6933 struct temp_slot *t;
6937 ggc_mark_rtx (t->slot);
6938 ggc_mark_rtx (t->address);
6939 ggc_mark_tree (t->rtl_expr);
6945 /* Mark P for GC. */
6948 mark_function_status (p)
6957 ggc_mark_rtx (p->arg_offset_rtx);
6959 if (p->x_parm_reg_stack_loc)
6960 for (i = p->x_max_parm_reg, r = p->x_parm_reg_stack_loc;
6964 ggc_mark_rtx (p->return_rtx);
6965 ggc_mark_rtx (p->x_cleanup_label);
6966 ggc_mark_rtx (p->x_return_label);
6967 ggc_mark_rtx (p->x_save_expr_regs);
6968 ggc_mark_rtx (p->x_stack_slot_list);
6969 ggc_mark_rtx (p->x_parm_birth_insn);
6970 ggc_mark_rtx (p->x_tail_recursion_label);
6971 ggc_mark_rtx (p->x_tail_recursion_reentry);
6972 ggc_mark_rtx (p->internal_arg_pointer);
6973 ggc_mark_rtx (p->x_arg_pointer_save_area);
6974 ggc_mark_tree (p->x_rtl_expr_chain);
6975 ggc_mark_rtx (p->x_last_parm_insn);
6976 ggc_mark_tree (p->x_context_display);
6977 ggc_mark_tree (p->x_trampoline_list);
6978 ggc_mark_rtx (p->epilogue_delay_list);
6980 mark_temp_slot (p->x_temp_slots);
6983 struct var_refs_queue *q = p->fixup_var_refs_queue;
6986 ggc_mark_rtx (q->modified);
6991 ggc_mark_rtx (p->x_nonlocal_goto_handler_slots);
6992 ggc_mark_rtx (p->x_nonlocal_goto_handler_labels);
6993 ggc_mark_rtx (p->x_nonlocal_goto_stack_level);
6994 ggc_mark_tree (p->x_nonlocal_labels);
6997 /* Mark the function chain ARG (which is really a struct function **)
7001 mark_function_chain (arg)
7004 struct function *f = *(struct function **) arg;
7006 for (; f; f = f->next_global)
7008 ggc_mark_tree (f->decl);
7010 mark_function_status (f);
7011 mark_eh_status (f->eh);
7012 mark_stmt_status (f->stmt);
7013 mark_expr_status (f->expr);
7014 mark_emit_status (f->emit);
7015 mark_varasm_status (f->varasm);
7017 if (mark_machine_status)
7018 (*mark_machine_status) (f);
7019 if (mark_lang_status)
7020 (*mark_lang_status) (f);
7022 if (f->original_arg_vector)
7023 ggc_mark_rtvec ((rtvec) f->original_arg_vector);
7024 if (f->original_decl_initial)
7025 ggc_mark_tree (f->original_decl_initial);
7029 /* Called once, at initialization, to initialize function.c. */
7032 init_function_once ()
7034 ggc_add_root (&all_functions, 1, sizeof all_functions,
7035 mark_function_chain);