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 ACCUMULATE_OUTGOING_ARGS
65 #define ACCUMULATE_OUTGOING_ARGS 0
68 #ifndef TRAMPOLINE_ALIGNMENT
69 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
72 #ifndef LOCAL_ALIGNMENT
73 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
76 #if !defined (PREFERRED_STACK_BOUNDARY) && defined (STACK_BOUNDARY)
77 #define PREFERRED_STACK_BOUNDARY STACK_BOUNDARY
80 /* Some systems use __main in a way incompatible with its use in gcc, in these
81 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
82 give the same symbol without quotes for an alternative entry point. You
83 must define both, or neither. */
85 #define NAME__MAIN "__main"
86 #define SYMBOL__MAIN __main
89 /* Round a value to the lowest integer less than it that is a multiple of
90 the required alignment. Avoid using division in case the value is
91 negative. Assume the alignment is a power of two. */
92 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
94 /* Similar, but round to the next highest integer that meets the
96 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
98 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
99 during rtl generation. If they are different register numbers, this is
100 always true. It may also be true if
101 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
102 generation. See fix_lexical_addr for details. */
104 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
105 #define NEED_SEPARATE_AP
108 /* Nonzero if function being compiled doesn't contain any calls
109 (ignoring the prologue and epilogue). This is set prior to
110 local register allocation and is valid for the remaining
112 int current_function_is_leaf;
114 /* Nonzero if function being compiled doesn't contain any instructions
115 that can throw an exception. This is set prior to final. */
117 int current_function_nothrow;
119 /* Nonzero if function being compiled doesn't modify the stack pointer
120 (ignoring the prologue and epilogue). This is only valid after
121 life_analysis has run. */
122 int current_function_sp_is_unchanging;
124 /* Nonzero if the function being compiled is a leaf function which only
125 uses leaf registers. This is valid after reload (specifically after
126 sched2) and is useful only if the port defines LEAF_REGISTERS. */
127 int current_function_uses_only_leaf_regs;
129 /* Nonzero once virtual register instantiation has been done.
130 assign_stack_local uses frame_pointer_rtx when this is nonzero. */
131 static int virtuals_instantiated;
133 /* These variables hold pointers to functions to
134 save and restore machine-specific data,
135 in push_function_context and pop_function_context. */
136 void (*init_machine_status) PARAMS ((struct function *));
137 void (*save_machine_status) PARAMS ((struct function *));
138 void (*restore_machine_status) PARAMS ((struct function *));
139 void (*mark_machine_status) PARAMS ((struct function *));
140 void (*free_machine_status) PARAMS ((struct function *));
142 /* Likewise, but for language-specific data. */
143 void (*init_lang_status) PARAMS ((struct function *));
144 void (*save_lang_status) PARAMS ((struct function *));
145 void (*restore_lang_status) PARAMS ((struct function *));
146 void (*mark_lang_status) PARAMS ((struct function *));
147 void (*free_lang_status) PARAMS ((struct function *));
149 /* The FUNCTION_DECL for an inline function currently being expanded. */
150 tree inline_function_decl;
152 /* The currently compiled function. */
153 struct function *cfun = 0;
155 /* Global list of all compiled functions. */
156 struct function *all_functions = 0;
158 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
159 static varray_type prologue;
160 static varray_type epilogue;
162 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
164 static varray_type sibcall_epilogue;
166 /* In order to evaluate some expressions, such as function calls returning
167 structures in memory, we need to temporarily allocate stack locations.
168 We record each allocated temporary in the following structure.
170 Associated with each temporary slot is a nesting level. When we pop up
171 one level, all temporaries associated with the previous level are freed.
172 Normally, all temporaries are freed after the execution of the statement
173 in which they were created. However, if we are inside a ({...}) grouping,
174 the result may be in a temporary and hence must be preserved. If the
175 result could be in a temporary, we preserve it if we can determine which
176 one it is in. If we cannot determine which temporary may contain the
177 result, all temporaries are preserved. A temporary is preserved by
178 pretending it was allocated at the previous nesting level.
180 Automatic variables are also assigned temporary slots, at the nesting
181 level where they are defined. They are marked a "kept" so that
182 free_temp_slots will not free them. */
186 /* Points to next temporary slot. */
187 struct temp_slot *next;
188 /* The rtx to used to reference the slot. */
190 /* The rtx used to represent the address if not the address of the
191 slot above. May be an EXPR_LIST if multiple addresses exist. */
193 /* The alignment (in bits) of the slot. */
195 /* The size, in units, of the slot. */
197 /* The alias set for the slot. If the alias set is zero, we don't
198 know anything about the alias set of the slot. We must only
199 reuse a slot if it is assigned an object of the same alias set.
200 Otherwise, the rest of the compiler may assume that the new use
201 of the slot cannot alias the old use of the slot, which is
202 false. If the slot has alias set zero, then we can't reuse the
203 slot at all, since we have no idea what alias set may have been
204 imposed on the memory. For example, if the stack slot is the
205 call frame for an inline functioned, we have no idea what alias
206 sets will be assigned to various pieces of the call frame. */
207 HOST_WIDE_INT alias_set;
208 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
210 /* Non-zero if this temporary is currently in use. */
212 /* Non-zero if this temporary has its address taken. */
214 /* Nesting level at which this slot is being used. */
216 /* Non-zero if this should survive a call to free_temp_slots. */
218 /* The offset of the slot from the frame_pointer, including extra space
219 for alignment. This info is for combine_temp_slots. */
220 HOST_WIDE_INT base_offset;
221 /* The size of the slot, including extra space for alignment. This
222 info is for combine_temp_slots. */
223 HOST_WIDE_INT full_size;
226 /* This structure is used to record MEMs or pseudos used to replace VAR, any
227 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
228 maintain this list in case two operands of an insn were required to match;
229 in that case we must ensure we use the same replacement. */
231 struct fixup_replacement
235 struct fixup_replacement *next;
238 struct insns_for_mem_entry {
239 /* The KEY in HE will be a MEM. */
240 struct hash_entry he;
241 /* These are the INSNS which reference the MEM. */
245 /* Forward declarations. */
247 static rtx assign_stack_local_1 PARAMS ((enum machine_mode, HOST_WIDE_INT,
248 int, struct function *));
249 static rtx assign_stack_temp_for_type PARAMS ((enum machine_mode,
250 HOST_WIDE_INT, int, tree));
251 static struct temp_slot *find_temp_slot_from_address PARAMS ((rtx));
252 static void put_reg_into_stack PARAMS ((struct function *, rtx, tree,
253 enum machine_mode, enum machine_mode,
254 int, unsigned int, int,
255 struct hash_table *));
256 static void schedule_fixup_var_refs PARAMS ((struct function *, rtx, tree,
258 struct hash_table *));
259 static void fixup_var_refs PARAMS ((rtx, enum machine_mode, int,
260 struct hash_table *));
261 static struct fixup_replacement
262 *find_fixup_replacement PARAMS ((struct fixup_replacement **, rtx));
263 static void fixup_var_refs_insns PARAMS ((rtx, enum machine_mode, int,
264 rtx, int, struct hash_table *));
265 static void fixup_var_refs_1 PARAMS ((rtx, enum machine_mode, rtx *, rtx,
266 struct fixup_replacement **));
267 static rtx fixup_memory_subreg PARAMS ((rtx, rtx, int));
268 static rtx walk_fixup_memory_subreg PARAMS ((rtx, rtx, int));
269 static rtx fixup_stack_1 PARAMS ((rtx, rtx));
270 static void optimize_bit_field PARAMS ((rtx, rtx, rtx *));
271 static void instantiate_decls PARAMS ((tree, int));
272 static void instantiate_decls_1 PARAMS ((tree, int));
273 static void instantiate_decl PARAMS ((rtx, HOST_WIDE_INT, int));
274 static int instantiate_virtual_regs_1 PARAMS ((rtx *, rtx, int));
275 static void delete_handlers PARAMS ((void));
276 static void pad_to_arg_alignment PARAMS ((struct args_size *, int,
277 struct args_size *));
278 #ifndef ARGS_GROW_DOWNWARD
279 static void pad_below PARAMS ((struct args_size *, enum machine_mode,
282 static rtx round_trampoline_addr PARAMS ((rtx));
283 static tree *identify_blocks_1 PARAMS ((rtx, tree *, tree *, tree *));
284 static void reorder_blocks_1 PARAMS ((rtx, tree, varray_type *));
285 static tree blocks_nreverse PARAMS ((tree));
286 static int all_blocks PARAMS ((tree, tree *));
287 static tree *get_block_vector PARAMS ((tree, int *));
288 /* We always define `record_insns' even if its not used so that we
289 can always export `prologue_epilogue_contains'. */
290 static void record_insns PARAMS ((rtx, varray_type *)) ATTRIBUTE_UNUSED;
291 static int contains PARAMS ((rtx, varray_type));
293 static void emit_return_into_block PARAMS ((basic_block, rtx));
295 static void put_addressof_into_stack PARAMS ((rtx, struct hash_table *));
296 static boolean purge_addressof_1 PARAMS ((rtx *, rtx, int, int,
297 struct hash_table *));
298 static int is_addressof PARAMS ((rtx *, void *));
299 static struct hash_entry *insns_for_mem_newfunc PARAMS ((struct hash_entry *,
302 static unsigned long insns_for_mem_hash PARAMS ((hash_table_key));
303 static boolean insns_for_mem_comp PARAMS ((hash_table_key, hash_table_key));
304 static int insns_for_mem_walk PARAMS ((rtx *, void *));
305 static void compute_insns_for_mem PARAMS ((rtx, rtx, struct hash_table *));
306 static void mark_temp_slot PARAMS ((struct temp_slot *));
307 static void mark_function_status PARAMS ((struct function *));
308 static void mark_function_chain PARAMS ((void *));
309 static void prepare_function_start PARAMS ((void));
310 static void do_clobber_return_reg PARAMS ((rtx, void *));
311 static void do_use_return_reg PARAMS ((rtx, void *));
313 /* Pointer to chain of `struct function' for containing functions. */
314 struct function *outer_function_chain;
316 /* Given a function decl for a containing function,
317 return the `struct function' for it. */
320 find_function_data (decl)
325 for (p = outer_function_chain; p; p = p->next)
332 /* Save the current context for compilation of a nested function.
333 This is called from language-specific code. The caller should use
334 the save_lang_status callback to save any language-specific state,
335 since this function knows only about language-independent
339 push_function_context_to (context)
342 struct function *p, *context_data;
346 context_data = (context == current_function_decl
348 : find_function_data (context));
349 context_data->contains_functions = 1;
353 init_dummy_function_start ();
356 p->next = outer_function_chain;
357 outer_function_chain = p;
358 p->fixup_var_refs_queue = 0;
360 save_tree_status (p);
361 if (save_lang_status)
362 (*save_lang_status) (p);
363 if (save_machine_status)
364 (*save_machine_status) (p);
370 push_function_context ()
372 push_function_context_to (current_function_decl);
375 /* Restore the last saved context, at the end of a nested function.
376 This function is called from language-specific code. */
379 pop_function_context_from (context)
380 tree context ATTRIBUTE_UNUSED;
382 struct function *p = outer_function_chain;
383 struct var_refs_queue *queue;
384 struct var_refs_queue *next;
387 outer_function_chain = p->next;
389 current_function_decl = p->decl;
392 restore_tree_status (p);
393 restore_emit_status (p);
395 if (restore_machine_status)
396 (*restore_machine_status) (p);
397 if (restore_lang_status)
398 (*restore_lang_status) (p);
400 /* Finish doing put_var_into_stack for any of our variables
401 which became addressable during the nested function. */
402 for (queue = p->fixup_var_refs_queue; queue; queue = next)
405 fixup_var_refs (queue->modified, queue->promoted_mode,
406 queue->unsignedp, 0);
409 p->fixup_var_refs_queue = 0;
411 /* Reset variables that have known state during rtx generation. */
412 rtx_equal_function_value_matters = 1;
413 virtuals_instantiated = 0;
417 pop_function_context ()
419 pop_function_context_from (current_function_decl);
422 /* Clear out all parts of the state in F that can safely be discarded
423 after the function has been parsed, but not compiled, to let
424 garbage collection reclaim the memory. */
427 free_after_parsing (f)
430 /* f->expr->forced_labels is used by code generation. */
431 /* f->emit->regno_reg_rtx is used by code generation. */
432 /* f->varasm is used by code generation. */
433 /* f->eh->eh_return_stub_label is used by code generation. */
435 if (free_lang_status)
436 (*free_lang_status) (f);
437 free_stmt_status (f);
440 /* Clear out all parts of the state in F that can safely be discarded
441 after the function has been compiled, to let garbage collection
442 reclaim the memory. */
445 free_after_compilation (f)
448 struct temp_slot *ts;
449 struct temp_slot *next;
452 free_expr_status (f);
453 free_emit_status (f);
454 free_varasm_status (f);
456 if (free_machine_status)
457 (*free_machine_status) (f);
459 if (f->x_parm_reg_stack_loc)
460 free (f->x_parm_reg_stack_loc);
462 for (ts = f->x_temp_slots; ts; ts = next)
467 f->x_temp_slots = NULL;
469 f->arg_offset_rtx = NULL;
470 f->return_rtx = NULL;
471 f->internal_arg_pointer = NULL;
472 f->x_nonlocal_labels = NULL;
473 f->x_nonlocal_goto_handler_slots = NULL;
474 f->x_nonlocal_goto_handler_labels = NULL;
475 f->x_nonlocal_goto_stack_level = NULL;
476 f->x_cleanup_label = NULL;
477 f->x_return_label = NULL;
478 f->x_save_expr_regs = NULL;
479 f->x_stack_slot_list = NULL;
480 f->x_rtl_expr_chain = NULL;
481 f->x_tail_recursion_label = NULL;
482 f->x_tail_recursion_reentry = NULL;
483 f->x_arg_pointer_save_area = NULL;
484 f->x_context_display = NULL;
485 f->x_trampoline_list = NULL;
486 f->x_parm_birth_insn = NULL;
487 f->x_last_parm_insn = NULL;
488 f->x_parm_reg_stack_loc = NULL;
489 f->fixup_var_refs_queue = NULL;
490 f->original_arg_vector = NULL;
491 f->original_decl_initial = NULL;
492 f->inl_last_parm_insn = NULL;
493 f->epilogue_delay_list = NULL;
497 /* Allocate fixed slots in the stack frame of the current function. */
499 /* Return size needed for stack frame based on slots so far allocated in
501 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
502 the caller may have to do that. */
505 get_func_frame_size (f)
508 #ifdef FRAME_GROWS_DOWNWARD
509 return -f->x_frame_offset;
511 return f->x_frame_offset;
515 /* Return size needed for stack frame based on slots so far allocated.
516 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
517 the caller may have to do that. */
521 return get_func_frame_size (cfun);
524 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
525 with machine mode MODE.
527 ALIGN controls the amount of alignment for the address of the slot:
528 0 means according to MODE,
529 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
530 positive specifies alignment boundary in bits.
532 We do not round to stack_boundary here.
534 FUNCTION specifies the function to allocate in. */
537 assign_stack_local_1 (mode, size, align, function)
538 enum machine_mode mode;
541 struct function *function;
543 register rtx x, addr;
544 int bigend_correction = 0;
547 /* Allocate in the memory associated with the function in whose frame
549 if (function != cfun)
550 push_obstacks (function->function_obstack,
551 function->function_maybepermanent_obstack);
558 alignment = BIGGEST_ALIGNMENT;
560 alignment = GET_MODE_ALIGNMENT (mode);
562 /* Allow the target to (possibly) increase the alignment of this
564 type = type_for_mode (mode, 0);
566 alignment = LOCAL_ALIGNMENT (type, alignment);
568 alignment /= BITS_PER_UNIT;
570 else if (align == -1)
572 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
573 size = CEIL_ROUND (size, alignment);
576 alignment = align / BITS_PER_UNIT;
578 #ifdef FRAME_GROWS_DOWNWARD
579 function->x_frame_offset -= size;
582 /* Ignore alignment we can't do with expected alignment of the boundary. */
583 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
584 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
586 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
587 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
589 /* Round frame offset to that alignment.
590 We must be careful here, since FRAME_OFFSET might be negative and
591 division with a negative dividend isn't as well defined as we might
592 like. So we instead assume that ALIGNMENT is a power of two and
593 use logical operations which are unambiguous. */
594 #ifdef FRAME_GROWS_DOWNWARD
595 function->x_frame_offset = FLOOR_ROUND (function->x_frame_offset, alignment);
597 function->x_frame_offset = CEIL_ROUND (function->x_frame_offset, alignment);
600 /* On a big-endian machine, if we are allocating more space than we will use,
601 use the least significant bytes of those that are allocated. */
602 if (BYTES_BIG_ENDIAN && mode != BLKmode)
603 bigend_correction = size - GET_MODE_SIZE (mode);
605 /* If we have already instantiated virtual registers, return the actual
606 address relative to the frame pointer. */
607 if (function == cfun && virtuals_instantiated)
608 addr = plus_constant (frame_pointer_rtx,
609 (frame_offset + bigend_correction
610 + STARTING_FRAME_OFFSET));
612 addr = plus_constant (virtual_stack_vars_rtx,
613 function->x_frame_offset + bigend_correction);
615 #ifndef FRAME_GROWS_DOWNWARD
616 function->x_frame_offset += size;
619 x = gen_rtx_MEM (mode, addr);
621 function->x_stack_slot_list
622 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
624 if (function != cfun)
630 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
634 assign_stack_local (mode, size, align)
635 enum machine_mode mode;
639 return assign_stack_local_1 (mode, size, align, cfun);
642 /* Allocate a temporary stack slot and record it for possible later
645 MODE is the machine mode to be given to the returned rtx.
647 SIZE is the size in units of the space required. We do no rounding here
648 since assign_stack_local will do any required rounding.
650 KEEP is 1 if this slot is to be retained after a call to
651 free_temp_slots. Automatic variables for a block are allocated
652 with this flag. KEEP is 2 if we allocate a longer term temporary,
653 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
654 if we are to allocate something at an inner level to be treated as
655 a variable in the block (e.g., a SAVE_EXPR).
657 TYPE is the type that will be used for the stack slot. */
660 assign_stack_temp_for_type (mode, size, keep, type)
661 enum machine_mode mode;
667 HOST_WIDE_INT alias_set;
668 struct temp_slot *p, *best_p = 0;
670 /* If SIZE is -1 it means that somebody tried to allocate a temporary
671 of a variable size. */
675 /* If we know the alias set for the memory that will be used, use
676 it. If there's no TYPE, then we don't know anything about the
677 alias set for the memory. */
679 alias_set = get_alias_set (type);
684 align = BIGGEST_ALIGNMENT;
686 align = GET_MODE_ALIGNMENT (mode);
689 type = type_for_mode (mode, 0);
692 align = LOCAL_ALIGNMENT (type, align);
694 /* Try to find an available, already-allocated temporary of the proper
695 mode which meets the size and alignment requirements. Choose the
696 smallest one with the closest alignment. */
697 for (p = temp_slots; p; p = p->next)
698 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
700 && (! flag_strict_aliasing
701 || (alias_set && p->alias_set == alias_set))
702 && (best_p == 0 || best_p->size > p->size
703 || (best_p->size == p->size && best_p->align > p->align)))
705 if (p->align == align && p->size == size)
713 /* Make our best, if any, the one to use. */
716 /* If there are enough aligned bytes left over, make them into a new
717 temp_slot so that the extra bytes don't get wasted. Do this only
718 for BLKmode slots, so that we can be sure of the alignment. */
719 if (GET_MODE (best_p->slot) == BLKmode)
721 int alignment = best_p->align / BITS_PER_UNIT;
722 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
724 if (best_p->size - rounded_size >= alignment)
726 p = (struct temp_slot *) xmalloc (sizeof (struct temp_slot));
727 p->in_use = p->addr_taken = 0;
728 p->size = best_p->size - rounded_size;
729 p->base_offset = best_p->base_offset + rounded_size;
730 p->full_size = best_p->full_size - rounded_size;
731 p->slot = gen_rtx_MEM (BLKmode,
732 plus_constant (XEXP (best_p->slot, 0),
734 p->align = best_p->align;
737 p->alias_set = best_p->alias_set;
738 p->next = temp_slots;
741 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
744 best_p->size = rounded_size;
745 best_p->full_size = rounded_size;
752 /* If we still didn't find one, make a new temporary. */
755 HOST_WIDE_INT frame_offset_old = frame_offset;
757 p = (struct temp_slot *) xmalloc (sizeof (struct temp_slot));
759 /* We are passing an explicit alignment request to assign_stack_local.
760 One side effect of that is assign_stack_local will not round SIZE
761 to ensure the frame offset remains suitably aligned.
763 So for requests which depended on the rounding of SIZE, we go ahead
764 and round it now. We also make sure ALIGNMENT is at least
765 BIGGEST_ALIGNMENT. */
766 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
768 p->slot = assign_stack_local (mode,
770 ? CEIL_ROUND (size, align / BITS_PER_UNIT)
775 p->alias_set = alias_set;
777 /* The following slot size computation is necessary because we don't
778 know the actual size of the temporary slot until assign_stack_local
779 has performed all the frame alignment and size rounding for the
780 requested temporary. Note that extra space added for alignment
781 can be either above or below this stack slot depending on which
782 way the frame grows. We include the extra space if and only if it
783 is above this slot. */
784 #ifdef FRAME_GROWS_DOWNWARD
785 p->size = frame_offset_old - frame_offset;
790 /* Now define the fields used by combine_temp_slots. */
791 #ifdef FRAME_GROWS_DOWNWARD
792 p->base_offset = frame_offset;
793 p->full_size = frame_offset_old - frame_offset;
795 p->base_offset = frame_offset_old;
796 p->full_size = frame_offset - frame_offset_old;
799 p->next = temp_slots;
805 p->rtl_expr = seq_rtl_expr;
809 p->level = target_temp_slot_level;
814 p->level = var_temp_slot_level;
819 p->level = temp_slot_level;
823 /* We may be reusing an old slot, so clear any MEM flags that may have been
825 RTX_UNCHANGING_P (p->slot) = 0;
826 MEM_IN_STRUCT_P (p->slot) = 0;
827 MEM_SCALAR_P (p->slot) = 0;
828 MEM_ALIAS_SET (p->slot) = alias_set;
831 MEM_SET_IN_STRUCT_P (p->slot, AGGREGATE_TYPE_P (type));
836 /* Allocate a temporary stack slot and record it for possible later
837 reuse. First three arguments are same as in preceding function. */
840 assign_stack_temp (mode, size, keep)
841 enum machine_mode mode;
845 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
848 /* Assign a temporary of given TYPE.
849 KEEP is as for assign_stack_temp.
850 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
851 it is 0 if a register is OK.
852 DONT_PROMOTE is 1 if we should not promote values in register
856 assign_temp (type, keep, memory_required, dont_promote)
860 int dont_promote ATTRIBUTE_UNUSED;
862 enum machine_mode mode = TYPE_MODE (type);
863 #ifndef PROMOTE_FOR_CALL_ONLY
864 int unsignedp = TREE_UNSIGNED (type);
867 if (mode == BLKmode || memory_required)
869 HOST_WIDE_INT size = int_size_in_bytes (type);
872 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
873 problems with allocating the stack space. */
877 /* Unfortunately, we don't yet know how to allocate variable-sized
878 temporaries. However, sometimes we have a fixed upper limit on
879 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
880 instead. This is the case for Chill variable-sized strings. */
881 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
882 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
883 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
884 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
886 tmp = assign_stack_temp_for_type (mode, size, keep, type);
890 #ifndef PROMOTE_FOR_CALL_ONLY
892 mode = promote_mode (type, mode, &unsignedp, 0);
895 return gen_reg_rtx (mode);
898 /* Combine temporary stack slots which are adjacent on the stack.
900 This allows for better use of already allocated stack space. This is only
901 done for BLKmode slots because we can be sure that we won't have alignment
902 problems in this case. */
905 combine_temp_slots ()
907 struct temp_slot *p, *q;
908 struct temp_slot *prev_p, *prev_q;
911 /* We can't combine slots, because the information about which slot
912 is in which alias set will be lost. */
913 if (flag_strict_aliasing)
916 /* If there are a lot of temp slots, don't do anything unless
917 high levels of optimizaton. */
918 if (! flag_expensive_optimizations)
919 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
920 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
923 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
927 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
928 for (q = p->next, prev_q = p; q; q = prev_q->next)
931 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
933 if (p->base_offset + p->full_size == q->base_offset)
935 /* Q comes after P; combine Q into P. */
937 p->full_size += q->full_size;
940 else if (q->base_offset + q->full_size == p->base_offset)
942 /* P comes after Q; combine P into Q. */
944 q->full_size += p->full_size;
949 /* Either delete Q or advance past it. */
952 prev_q->next = q->next;
958 /* Either delete P or advance past it. */
962 prev_p->next = p->next;
964 temp_slots = p->next;
971 /* Find the temp slot corresponding to the object at address X. */
973 static struct temp_slot *
974 find_temp_slot_from_address (x)
980 for (p = temp_slots; p; p = p->next)
985 else if (XEXP (p->slot, 0) == x
987 || (GET_CODE (x) == PLUS
988 && XEXP (x, 0) == virtual_stack_vars_rtx
989 && GET_CODE (XEXP (x, 1)) == CONST_INT
990 && INTVAL (XEXP (x, 1)) >= p->base_offset
991 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
994 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
995 for (next = p->address; next; next = XEXP (next, 1))
996 if (XEXP (next, 0) == x)
1000 /* If we have a sum involving a register, see if it points to a temp
1002 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == REG
1003 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
1005 else if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == REG
1006 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
1012 /* Indicate that NEW is an alternate way of referring to the temp slot
1013 that previously was known by OLD. */
1016 update_temp_slot_address (old, new)
1019 struct temp_slot *p;
1021 if (rtx_equal_p (old, new))
1024 p = find_temp_slot_from_address (old);
1026 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
1027 is a register, see if one operand of the PLUS is a temporary
1028 location. If so, NEW points into it. Otherwise, if both OLD and
1029 NEW are a PLUS and if there is a register in common between them.
1030 If so, try a recursive call on those values. */
1033 if (GET_CODE (old) != PLUS)
1036 if (GET_CODE (new) == REG)
1038 update_temp_slot_address (XEXP (old, 0), new);
1039 update_temp_slot_address (XEXP (old, 1), new);
1042 else if (GET_CODE (new) != PLUS)
1045 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
1046 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
1047 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
1048 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
1049 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
1050 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
1051 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
1052 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
1057 /* Otherwise add an alias for the temp's address. */
1058 else if (p->address == 0)
1062 if (GET_CODE (p->address) != EXPR_LIST)
1063 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1065 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1069 /* If X could be a reference to a temporary slot, mark the fact that its
1070 address was taken. */
1073 mark_temp_addr_taken (x)
1076 struct temp_slot *p;
1081 /* If X is not in memory or is at a constant address, it cannot be in
1082 a temporary slot. */
1083 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1086 p = find_temp_slot_from_address (XEXP (x, 0));
1091 /* If X could be a reference to a temporary slot, mark that slot as
1092 belonging to the to one level higher than the current level. If X
1093 matched one of our slots, just mark that one. Otherwise, we can't
1094 easily predict which it is, so upgrade all of them. Kept slots
1095 need not be touched.
1097 This is called when an ({...}) construct occurs and a statement
1098 returns a value in memory. */
1101 preserve_temp_slots (x)
1104 struct temp_slot *p = 0;
1106 /* If there is no result, we still might have some objects whose address
1107 were taken, so we need to make sure they stay around. */
1110 for (p = temp_slots; p; p = p->next)
1111 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1117 /* If X is a register that is being used as a pointer, see if we have
1118 a temporary slot we know it points to. To be consistent with
1119 the code below, we really should preserve all non-kept slots
1120 if we can't find a match, but that seems to be much too costly. */
1121 if (GET_CODE (x) == REG && REGNO_POINTER_FLAG (REGNO (x)))
1122 p = find_temp_slot_from_address (x);
1124 /* If X is not in memory or is at a constant address, it cannot be in
1125 a temporary slot, but it can contain something whose address was
1127 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1129 for (p = temp_slots; p; p = p->next)
1130 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1136 /* First see if we can find a match. */
1138 p = find_temp_slot_from_address (XEXP (x, 0));
1142 /* Move everything at our level whose address was taken to our new
1143 level in case we used its address. */
1144 struct temp_slot *q;
1146 if (p->level == temp_slot_level)
1148 for (q = temp_slots; q; q = q->next)
1149 if (q != p && q->addr_taken && q->level == p->level)
1158 /* Otherwise, preserve all non-kept slots at this level. */
1159 for (p = temp_slots; p; p = p->next)
1160 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1164 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1165 with that RTL_EXPR, promote it into a temporary slot at the present
1166 level so it will not be freed when we free slots made in the
1170 preserve_rtl_expr_result (x)
1173 struct temp_slot *p;
1175 /* If X is not in memory or is at a constant address, it cannot be in
1176 a temporary slot. */
1177 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1180 /* If we can find a match, move it to our level unless it is already at
1182 p = find_temp_slot_from_address (XEXP (x, 0));
1185 p->level = MIN (p->level, temp_slot_level);
1192 /* Free all temporaries used so far. This is normally called at the end
1193 of generating code for a statement. Don't free any temporaries
1194 currently in use for an RTL_EXPR that hasn't yet been emitted.
1195 We could eventually do better than this since it can be reused while
1196 generating the same RTL_EXPR, but this is complex and probably not
1202 struct temp_slot *p;
1204 for (p = temp_slots; p; p = p->next)
1205 if (p->in_use && p->level == temp_slot_level && ! p->keep
1206 && p->rtl_expr == 0)
1209 combine_temp_slots ();
1212 /* Free all temporary slots used in T, an RTL_EXPR node. */
1215 free_temps_for_rtl_expr (t)
1218 struct temp_slot *p;
1220 for (p = temp_slots; p; p = p->next)
1221 if (p->rtl_expr == t)
1223 /* If this slot is below the current TEMP_SLOT_LEVEL, then it
1224 needs to be preserved. This can happen if a temporary in
1225 the RTL_EXPR was addressed; preserve_temp_slots will move
1226 the temporary into a higher level. */
1227 if (temp_slot_level <= p->level)
1230 p->rtl_expr = NULL_TREE;
1233 combine_temp_slots ();
1236 /* Mark all temporaries ever allocated in this function as not suitable
1237 for reuse until the current level is exited. */
1240 mark_all_temps_used ()
1242 struct temp_slot *p;
1244 for (p = temp_slots; p; p = p->next)
1246 p->in_use = p->keep = 1;
1247 p->level = MIN (p->level, temp_slot_level);
1251 /* Push deeper into the nesting level for stack temporaries. */
1259 /* Likewise, but save the new level as the place to allocate variables
1264 push_temp_slots_for_block ()
1268 var_temp_slot_level = temp_slot_level;
1271 /* Likewise, but save the new level as the place to allocate temporaries
1272 for TARGET_EXPRs. */
1275 push_temp_slots_for_target ()
1279 target_temp_slot_level = temp_slot_level;
1282 /* Set and get the value of target_temp_slot_level. The only
1283 permitted use of these functions is to save and restore this value. */
1286 get_target_temp_slot_level ()
1288 return target_temp_slot_level;
1292 set_target_temp_slot_level (level)
1295 target_temp_slot_level = level;
1299 /* Pop a temporary nesting level. All slots in use in the current level
1305 struct temp_slot *p;
1307 for (p = temp_slots; p; p = p->next)
1308 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1311 combine_temp_slots ();
1316 /* Initialize temporary slots. */
1321 /* We have not allocated any temporaries yet. */
1323 temp_slot_level = 0;
1324 var_temp_slot_level = 0;
1325 target_temp_slot_level = 0;
1328 /* Retroactively move an auto variable from a register to a stack slot.
1329 This is done when an address-reference to the variable is seen. */
1332 put_var_into_stack (decl)
1336 enum machine_mode promoted_mode, decl_mode;
1337 struct function *function = 0;
1339 int can_use_addressof;
1340 int volatilep = TREE_CODE (decl) != SAVE_EXPR && TREE_THIS_VOLATILE (decl);
1341 int usedp = (TREE_USED (decl)
1342 || (TREE_CODE (decl) != SAVE_EXPR && DECL_INITIAL (decl) != 0));
1344 context = decl_function_context (decl);
1346 /* Get the current rtl used for this object and its original mode. */
1347 reg = TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl) : DECL_RTL (decl);
1349 /* No need to do anything if decl has no rtx yet
1350 since in that case caller is setting TREE_ADDRESSABLE
1351 and a stack slot will be assigned when the rtl is made. */
1355 /* Get the declared mode for this object. */
1356 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1357 : DECL_MODE (decl));
1358 /* Get the mode it's actually stored in. */
1359 promoted_mode = GET_MODE (reg);
1361 /* If this variable comes from an outer function,
1362 find that function's saved context. */
1363 if (context != current_function_decl && context != inline_function_decl)
1364 for (function = outer_function_chain; function; function = function->next)
1365 if (function->decl == context)
1368 /* If this is a variable-size object with a pseudo to address it,
1369 put that pseudo into the stack, if the var is nonlocal. */
1370 if (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl)
1371 && GET_CODE (reg) == MEM
1372 && GET_CODE (XEXP (reg, 0)) == REG
1373 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1375 reg = XEXP (reg, 0);
1376 decl_mode = promoted_mode = GET_MODE (reg);
1382 /* FIXME make it work for promoted modes too */
1383 && decl_mode == promoted_mode
1384 #ifdef NON_SAVING_SETJMP
1385 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1389 /* If we can't use ADDRESSOF, make sure we see through one we already
1391 if (! can_use_addressof && GET_CODE (reg) == MEM
1392 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1393 reg = XEXP (XEXP (reg, 0), 0);
1395 /* Now we should have a value that resides in one or more pseudo regs. */
1397 if (GET_CODE (reg) == REG)
1399 /* If this variable lives in the current function and we don't need
1400 to put things in the stack for the sake of setjmp, try to keep it
1401 in a register until we know we actually need the address. */
1402 if (can_use_addressof)
1403 gen_mem_addressof (reg, decl);
1405 put_reg_into_stack (function, reg, TREE_TYPE (decl), promoted_mode,
1406 decl_mode, volatilep, 0, usedp, 0);
1408 else if (GET_CODE (reg) == CONCAT)
1410 /* A CONCAT contains two pseudos; put them both in the stack.
1411 We do it so they end up consecutive.
1412 We fixup references to the parts only after we fixup references
1413 to the whole CONCAT, lest we do double fixups for the latter
1415 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1416 tree part_type = type_for_mode (part_mode, 0);
1417 rtx lopart = XEXP (reg, 0);
1418 rtx hipart = XEXP (reg, 1);
1419 #ifdef FRAME_GROWS_DOWNWARD
1420 /* Since part 0 should have a lower address, do it second. */
1421 put_reg_into_stack (function, hipart, part_type, part_mode,
1422 part_mode, volatilep, 0, 0, 0);
1423 put_reg_into_stack (function, lopart, part_type, part_mode,
1424 part_mode, volatilep, 0, 0, 0);
1426 put_reg_into_stack (function, lopart, part_type, part_mode,
1427 part_mode, volatilep, 0, 0, 0);
1428 put_reg_into_stack (function, hipart, part_type, part_mode,
1429 part_mode, volatilep, 0, 0, 0);
1432 /* Change the CONCAT into a combined MEM for both parts. */
1433 PUT_CODE (reg, MEM);
1434 set_mem_attributes (reg, decl, 1);
1436 /* The two parts are in memory order already.
1437 Use the lower parts address as ours. */
1438 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1439 /* Prevent sharing of rtl that might lose. */
1440 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1441 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1444 schedule_fixup_var_refs (function, reg, TREE_TYPE (decl),
1446 schedule_fixup_var_refs (function, lopart, part_type, part_mode, 0);
1447 schedule_fixup_var_refs (function, hipart, part_type, part_mode, 0);
1453 if (current_function_check_memory_usage)
1454 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
1455 XEXP (reg, 0), Pmode,
1456 GEN_INT (GET_MODE_SIZE (GET_MODE (reg))),
1457 TYPE_MODE (sizetype),
1458 GEN_INT (MEMORY_USE_RW),
1459 TYPE_MODE (integer_type_node));
1462 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1463 into the stack frame of FUNCTION (0 means the current function).
1464 DECL_MODE is the machine mode of the user-level data type.
1465 PROMOTED_MODE is the machine mode of the register.
1466 VOLATILE_P is nonzero if this is for a "volatile" decl.
1467 USED_P is nonzero if this reg might have already been used in an insn. */
1470 put_reg_into_stack (function, reg, type, promoted_mode, decl_mode, volatile_p,
1471 original_regno, used_p, ht)
1472 struct function *function;
1475 enum machine_mode promoted_mode, decl_mode;
1477 unsigned int original_regno;
1479 struct hash_table *ht;
1481 struct function *func = function ? function : cfun;
1483 unsigned int regno = original_regno;
1486 regno = REGNO (reg);
1488 if (regno < func->x_max_parm_reg)
1489 new = func->x_parm_reg_stack_loc[regno];
1492 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode), 0, func);
1494 PUT_CODE (reg, MEM);
1495 PUT_MODE (reg, decl_mode);
1496 XEXP (reg, 0) = XEXP (new, 0);
1497 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1498 MEM_VOLATILE_P (reg) = volatile_p;
1500 /* If this is a memory ref that contains aggregate components,
1501 mark it as such for cse and loop optimize. If we are reusing a
1502 previously generated stack slot, then we need to copy the bit in
1503 case it was set for other reasons. For instance, it is set for
1504 __builtin_va_alist. */
1505 MEM_SET_IN_STRUCT_P (reg,
1506 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1507 MEM_ALIAS_SET (reg) = get_alias_set (type);
1509 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht);
1512 /* Make sure that all refs to the variable, previously made
1513 when it was a register, are fixed up to be valid again.
1514 See function above for meaning of arguments. */
1516 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht)
1517 struct function *function;
1520 enum machine_mode promoted_mode;
1521 struct hash_table *ht;
1525 struct var_refs_queue *temp;
1528 = (struct var_refs_queue *) xmalloc (sizeof (struct var_refs_queue));
1529 temp->modified = reg;
1530 temp->promoted_mode = promoted_mode;
1531 temp->unsignedp = TREE_UNSIGNED (type);
1532 temp->next = function->fixup_var_refs_queue;
1533 function->fixup_var_refs_queue = temp;
1536 /* Variable is local; fix it up now. */
1537 fixup_var_refs (reg, promoted_mode, TREE_UNSIGNED (type), ht);
1541 fixup_var_refs (var, promoted_mode, unsignedp, ht)
1543 enum machine_mode promoted_mode;
1545 struct hash_table *ht;
1548 rtx first_insn = get_insns ();
1549 struct sequence_stack *stack = seq_stack;
1550 tree rtl_exps = rtl_expr_chain;
1553 /* Must scan all insns for stack-refs that exceed the limit. */
1554 fixup_var_refs_insns (var, promoted_mode, unsignedp, first_insn,
1556 /* If there's a hash table, it must record all uses of VAR. */
1560 /* Scan all pending sequences too. */
1561 for (; stack; stack = stack->next)
1563 push_to_sequence (stack->first);
1564 fixup_var_refs_insns (var, promoted_mode, unsignedp,
1565 stack->first, stack->next != 0, 0);
1566 /* Update remembered end of sequence
1567 in case we added an insn at the end. */
1568 stack->last = get_last_insn ();
1572 /* Scan all waiting RTL_EXPRs too. */
1573 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1575 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1576 if (seq != const0_rtx && seq != 0)
1578 push_to_sequence (seq);
1579 fixup_var_refs_insns (var, promoted_mode, unsignedp, seq, 0,
1585 /* Scan the catch clauses for exception handling too. */
1586 push_to_full_sequence (catch_clauses, catch_clauses_last);
1587 fixup_var_refs_insns (var, promoted_mode, unsignedp, catch_clauses,
1589 end_full_sequence (&catch_clauses, &catch_clauses_last);
1591 /* Scan sequences saved in CALL_PLACEHOLDERS too. */
1592 for (insn = first_insn; insn; insn = NEXT_INSN (insn))
1594 if (GET_CODE (insn) == CALL_INSN
1595 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
1599 /* Look at the Normal call, sibling call and tail recursion
1600 sequences attached to the CALL_PLACEHOLDER. */
1601 for (i = 0; i < 3; i++)
1603 rtx seq = XEXP (PATTERN (insn), i);
1606 push_to_sequence (seq);
1607 fixup_var_refs_insns (var, promoted_mode, unsignedp,
1609 XEXP (PATTERN (insn), i) = get_insns ();
1617 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1618 some part of an insn. Return a struct fixup_replacement whose OLD
1619 value is equal to X. Allocate a new structure if no such entry exists. */
1621 static struct fixup_replacement *
1622 find_fixup_replacement (replacements, x)
1623 struct fixup_replacement **replacements;
1626 struct fixup_replacement *p;
1628 /* See if we have already replaced this. */
1629 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1634 p = (struct fixup_replacement *) oballoc (sizeof (struct fixup_replacement));
1637 p->next = *replacements;
1644 /* Scan the insn-chain starting with INSN for refs to VAR
1645 and fix them up. TOPLEVEL is nonzero if this chain is the
1646 main chain of insns for the current function. */
1649 fixup_var_refs_insns (var, promoted_mode, unsignedp, insn, toplevel, ht)
1651 enum machine_mode promoted_mode;
1655 struct hash_table *ht;
1658 rtx insn_list = NULL_RTX;
1660 /* If we already know which INSNs reference VAR there's no need
1661 to walk the entire instruction chain. */
1664 insn_list = ((struct insns_for_mem_entry *)
1665 hash_lookup (ht, var, /*create=*/0, /*copy=*/0))->insns;
1666 insn = insn_list ? XEXP (insn_list, 0) : NULL_RTX;
1667 insn_list = XEXP (insn_list, 1);
1672 rtx next = NEXT_INSN (insn);
1673 rtx set, prev, prev_set;
1678 /* Remember the notes in case we delete the insn. */
1679 note = REG_NOTES (insn);
1681 /* If this is a CLOBBER of VAR, delete it.
1683 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1684 and REG_RETVAL notes too. */
1685 if (GET_CODE (PATTERN (insn)) == CLOBBER
1686 && (XEXP (PATTERN (insn), 0) == var
1687 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1688 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1689 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1691 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1692 /* The REG_LIBCALL note will go away since we are going to
1693 turn INSN into a NOTE, so just delete the
1694 corresponding REG_RETVAL note. */
1695 remove_note (XEXP (note, 0),
1696 find_reg_note (XEXP (note, 0), REG_RETVAL,
1699 /* In unoptimized compilation, we shouldn't call delete_insn
1700 except in jump.c doing warnings. */
1701 PUT_CODE (insn, NOTE);
1702 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1703 NOTE_SOURCE_FILE (insn) = 0;
1706 /* The insn to load VAR from a home in the arglist
1707 is now a no-op. When we see it, just delete it.
1708 Similarly if this is storing VAR from a register from which
1709 it was loaded in the previous insn. This will occur
1710 when an ADDRESSOF was made for an arglist slot. */
1712 && (set = single_set (insn)) != 0
1713 && SET_DEST (set) == var
1714 /* If this represents the result of an insn group,
1715 don't delete the insn. */
1716 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1717 && (rtx_equal_p (SET_SRC (set), var)
1718 || (GET_CODE (SET_SRC (set)) == REG
1719 && (prev = prev_nonnote_insn (insn)) != 0
1720 && (prev_set = single_set (prev)) != 0
1721 && SET_DEST (prev_set) == SET_SRC (set)
1722 && rtx_equal_p (SET_SRC (prev_set), var))))
1724 /* In unoptimized compilation, we shouldn't call delete_insn
1725 except in jump.c doing warnings. */
1726 PUT_CODE (insn, NOTE);
1727 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1728 NOTE_SOURCE_FILE (insn) = 0;
1729 if (insn == last_parm_insn)
1730 last_parm_insn = PREV_INSN (next);
1734 struct fixup_replacement *replacements = 0;
1735 rtx next_insn = NEXT_INSN (insn);
1737 if (SMALL_REGISTER_CLASSES)
1739 /* If the insn that copies the results of a CALL_INSN
1740 into a pseudo now references VAR, we have to use an
1741 intermediate pseudo since we want the life of the
1742 return value register to be only a single insn.
1744 If we don't use an intermediate pseudo, such things as
1745 address computations to make the address of VAR valid
1746 if it is not can be placed between the CALL_INSN and INSN.
1748 To make sure this doesn't happen, we record the destination
1749 of the CALL_INSN and see if the next insn uses both that
1752 if (call_dest != 0 && GET_CODE (insn) == INSN
1753 && reg_mentioned_p (var, PATTERN (insn))
1754 && reg_mentioned_p (call_dest, PATTERN (insn)))
1756 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1758 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1760 PATTERN (insn) = replace_rtx (PATTERN (insn),
1764 if (GET_CODE (insn) == CALL_INSN
1765 && GET_CODE (PATTERN (insn)) == SET)
1766 call_dest = SET_DEST (PATTERN (insn));
1767 else if (GET_CODE (insn) == CALL_INSN
1768 && GET_CODE (PATTERN (insn)) == PARALLEL
1769 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1770 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1775 /* See if we have to do anything to INSN now that VAR is in
1776 memory. If it needs to be loaded into a pseudo, use a single
1777 pseudo for the entire insn in case there is a MATCH_DUP
1778 between two operands. We pass a pointer to the head of
1779 a list of struct fixup_replacements. If fixup_var_refs_1
1780 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1781 it will record them in this list.
1783 If it allocated a pseudo for any replacement, we copy into
1786 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1789 /* If this is last_parm_insn, and any instructions were output
1790 after it to fix it up, then we must set last_parm_insn to
1791 the last such instruction emitted. */
1792 if (insn == last_parm_insn)
1793 last_parm_insn = PREV_INSN (next_insn);
1795 while (replacements)
1797 if (GET_CODE (replacements->new) == REG)
1802 /* OLD might be a (subreg (mem)). */
1803 if (GET_CODE (replacements->old) == SUBREG)
1805 = fixup_memory_subreg (replacements->old, insn, 0);
1808 = fixup_stack_1 (replacements->old, insn);
1810 insert_before = insn;
1812 /* If we are changing the mode, do a conversion.
1813 This might be wasteful, but combine.c will
1814 eliminate much of the waste. */
1816 if (GET_MODE (replacements->new)
1817 != GET_MODE (replacements->old))
1820 convert_move (replacements->new,
1821 replacements->old, unsignedp);
1822 seq = gen_sequence ();
1826 seq = gen_move_insn (replacements->new,
1829 emit_insn_before (seq, insert_before);
1832 replacements = replacements->next;
1836 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1837 But don't touch other insns referred to by reg-notes;
1838 we will get them elsewhere. */
1841 if (GET_CODE (note) != INSN_LIST)
1843 = walk_fixup_memory_subreg (XEXP (note, 0), insn, 1);
1844 note = XEXP (note, 1);
1852 insn = XEXP (insn_list, 0);
1853 insn_list = XEXP (insn_list, 1);
1860 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1861 See if the rtx expression at *LOC in INSN needs to be changed.
1863 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1864 contain a list of original rtx's and replacements. If we find that we need
1865 to modify this insn by replacing a memory reference with a pseudo or by
1866 making a new MEM to implement a SUBREG, we consult that list to see if
1867 we have already chosen a replacement. If none has already been allocated,
1868 we allocate it and update the list. fixup_var_refs_insns will copy VAR
1869 or the SUBREG, as appropriate, to the pseudo. */
1872 fixup_var_refs_1 (var, promoted_mode, loc, insn, replacements)
1874 enum machine_mode promoted_mode;
1877 struct fixup_replacement **replacements;
1880 register rtx x = *loc;
1881 RTX_CODE code = GET_CODE (x);
1882 register const char *fmt;
1883 register rtx tem, tem1;
1884 struct fixup_replacement *replacement;
1889 if (XEXP (x, 0) == var)
1891 /* Prevent sharing of rtl that might lose. */
1892 rtx sub = copy_rtx (XEXP (var, 0));
1894 if (! validate_change (insn, loc, sub, 0))
1896 rtx y = gen_reg_rtx (GET_MODE (sub));
1899 /* We should be able to replace with a register or all is lost.
1900 Note that we can't use validate_change to verify this, since
1901 we're not caring for replacing all dups simultaneously. */
1902 if (! validate_replace_rtx (*loc, y, insn))
1905 /* Careful! First try to recognize a direct move of the
1906 value, mimicking how things are done in gen_reload wrt
1907 PLUS. Consider what happens when insn is a conditional
1908 move instruction and addsi3 clobbers flags. */
1911 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1912 seq = gen_sequence ();
1915 if (recog_memoized (new_insn) < 0)
1917 /* That failed. Fall back on force_operand and hope. */
1920 force_operand (sub, y);
1921 seq = gen_sequence ();
1926 /* Don't separate setter from user. */
1927 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1928 insn = PREV_INSN (insn);
1931 emit_insn_before (seq, insn);
1939 /* If we already have a replacement, use it. Otherwise,
1940 try to fix up this address in case it is invalid. */
1942 replacement = find_fixup_replacement (replacements, var);
1943 if (replacement->new)
1945 *loc = replacement->new;
1949 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1951 /* Unless we are forcing memory to register or we changed the mode,
1952 we can leave things the way they are if the insn is valid. */
1954 INSN_CODE (insn) = -1;
1955 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1956 && recog_memoized (insn) >= 0)
1959 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1963 /* If X contains VAR, we need to unshare it here so that we update
1964 each occurrence separately. But all identical MEMs in one insn
1965 must be replaced with the same rtx because of the possibility of
1968 if (reg_mentioned_p (var, x))
1970 replacement = find_fixup_replacement (replacements, x);
1971 if (replacement->new == 0)
1972 replacement->new = copy_most_rtx (x, var);
1974 *loc = x = replacement->new;
1990 /* Note that in some cases those types of expressions are altered
1991 by optimize_bit_field, and do not survive to get here. */
1992 if (XEXP (x, 0) == var
1993 || (GET_CODE (XEXP (x, 0)) == SUBREG
1994 && SUBREG_REG (XEXP (x, 0)) == var))
1996 /* Get TEM as a valid MEM in the mode presently in the insn.
1998 We don't worry about the possibility of MATCH_DUP here; it
1999 is highly unlikely and would be tricky to handle. */
2002 if (GET_CODE (tem) == SUBREG)
2004 if (GET_MODE_BITSIZE (GET_MODE (tem))
2005 > GET_MODE_BITSIZE (GET_MODE (var)))
2007 replacement = find_fixup_replacement (replacements, var);
2008 if (replacement->new == 0)
2009 replacement->new = gen_reg_rtx (GET_MODE (var));
2010 SUBREG_REG (tem) = replacement->new;
2013 tem = fixup_memory_subreg (tem, insn, 0);
2016 tem = fixup_stack_1 (tem, insn);
2018 /* Unless we want to load from memory, get TEM into the proper mode
2019 for an extract from memory. This can only be done if the
2020 extract is at a constant position and length. */
2022 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
2023 && GET_CODE (XEXP (x, 2)) == CONST_INT
2024 && ! mode_dependent_address_p (XEXP (tem, 0))
2025 && ! MEM_VOLATILE_P (tem))
2027 enum machine_mode wanted_mode = VOIDmode;
2028 enum machine_mode is_mode = GET_MODE (tem);
2029 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
2032 if (GET_CODE (x) == ZERO_EXTRACT)
2035 = insn_data[(int) CODE_FOR_extzv].operand[1].mode;
2036 if (wanted_mode == VOIDmode)
2037 wanted_mode = word_mode;
2041 if (GET_CODE (x) == SIGN_EXTRACT)
2043 wanted_mode = insn_data[(int) CODE_FOR_extv].operand[1].mode;
2044 if (wanted_mode == VOIDmode)
2045 wanted_mode = word_mode;
2048 /* If we have a narrower mode, we can do something. */
2049 if (wanted_mode != VOIDmode
2050 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2052 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2053 rtx old_pos = XEXP (x, 2);
2056 /* If the bytes and bits are counted differently, we
2057 must adjust the offset. */
2058 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2059 offset = (GET_MODE_SIZE (is_mode)
2060 - GET_MODE_SIZE (wanted_mode) - offset);
2062 pos %= GET_MODE_BITSIZE (wanted_mode);
2064 newmem = gen_rtx_MEM (wanted_mode,
2065 plus_constant (XEXP (tem, 0), offset));
2066 MEM_COPY_ATTRIBUTES (newmem, tem);
2068 /* Make the change and see if the insn remains valid. */
2069 INSN_CODE (insn) = -1;
2070 XEXP (x, 0) = newmem;
2071 XEXP (x, 2) = GEN_INT (pos);
2073 if (recog_memoized (insn) >= 0)
2076 /* Otherwise, restore old position. XEXP (x, 0) will be
2078 XEXP (x, 2) = old_pos;
2082 /* If we get here, the bitfield extract insn can't accept a memory
2083 reference. Copy the input into a register. */
2085 tem1 = gen_reg_rtx (GET_MODE (tem));
2086 emit_insn_before (gen_move_insn (tem1, tem), insn);
2093 if (SUBREG_REG (x) == var)
2095 /* If this is a special SUBREG made because VAR was promoted
2096 from a wider mode, replace it with VAR and call ourself
2097 recursively, this time saying that the object previously
2098 had its current mode (by virtue of the SUBREG). */
2100 if (SUBREG_PROMOTED_VAR_P (x))
2103 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements);
2107 /* If this SUBREG makes VAR wider, it has become a paradoxical
2108 SUBREG with VAR in memory, but these aren't allowed at this
2109 stage of the compilation. So load VAR into a pseudo and take
2110 a SUBREG of that pseudo. */
2111 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2113 replacement = find_fixup_replacement (replacements, var);
2114 if (replacement->new == 0)
2115 replacement->new = gen_reg_rtx (GET_MODE (var));
2116 SUBREG_REG (x) = replacement->new;
2120 /* See if we have already found a replacement for this SUBREG.
2121 If so, use it. Otherwise, make a MEM and see if the insn
2122 is recognized. If not, or if we should force MEM into a register,
2123 make a pseudo for this SUBREG. */
2124 replacement = find_fixup_replacement (replacements, x);
2125 if (replacement->new)
2127 *loc = replacement->new;
2131 replacement->new = *loc = fixup_memory_subreg (x, insn, 0);
2133 INSN_CODE (insn) = -1;
2134 if (! flag_force_mem && recog_memoized (insn) >= 0)
2137 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2143 /* First do special simplification of bit-field references. */
2144 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2145 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2146 optimize_bit_field (x, insn, 0);
2147 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2148 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2149 optimize_bit_field (x, insn, NULL_PTR);
2151 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2152 into a register and then store it back out. */
2153 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2154 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2155 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2156 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2157 > GET_MODE_SIZE (GET_MODE (var))))
2159 replacement = find_fixup_replacement (replacements, var);
2160 if (replacement->new == 0)
2161 replacement->new = gen_reg_rtx (GET_MODE (var));
2163 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2164 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2167 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2168 insn into a pseudo and store the low part of the pseudo into VAR. */
2169 if (GET_CODE (SET_DEST (x)) == SUBREG
2170 && SUBREG_REG (SET_DEST (x)) == var
2171 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2172 > GET_MODE_SIZE (GET_MODE (var))))
2174 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2175 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2182 rtx dest = SET_DEST (x);
2183 rtx src = SET_SRC (x);
2185 rtx outerdest = dest;
2188 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2189 || GET_CODE (dest) == SIGN_EXTRACT
2190 || GET_CODE (dest) == ZERO_EXTRACT)
2191 dest = XEXP (dest, 0);
2193 if (GET_CODE (src) == SUBREG)
2194 src = XEXP (src, 0);
2196 /* If VAR does not appear at the top level of the SET
2197 just scan the lower levels of the tree. */
2199 if (src != var && dest != var)
2202 /* We will need to rerecognize this insn. */
2203 INSN_CODE (insn) = -1;
2206 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var)
2208 /* Since this case will return, ensure we fixup all the
2210 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2211 insn, replacements);
2212 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2213 insn, replacements);
2214 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2215 insn, replacements);
2217 tem = XEXP (outerdest, 0);
2219 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2220 that may appear inside a ZERO_EXTRACT.
2221 This was legitimate when the MEM was a REG. */
2222 if (GET_CODE (tem) == SUBREG
2223 && SUBREG_REG (tem) == var)
2224 tem = fixup_memory_subreg (tem, insn, 0);
2226 tem = fixup_stack_1 (tem, insn);
2228 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2229 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2230 && ! mode_dependent_address_p (XEXP (tem, 0))
2231 && ! MEM_VOLATILE_P (tem))
2233 enum machine_mode wanted_mode;
2234 enum machine_mode is_mode = GET_MODE (tem);
2235 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2237 wanted_mode = insn_data[(int) CODE_FOR_insv].operand[0].mode;
2238 if (wanted_mode == VOIDmode)
2239 wanted_mode = word_mode;
2241 /* If we have a narrower mode, we can do something. */
2242 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2244 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2245 rtx old_pos = XEXP (outerdest, 2);
2248 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2249 offset = (GET_MODE_SIZE (is_mode)
2250 - GET_MODE_SIZE (wanted_mode) - offset);
2252 pos %= GET_MODE_BITSIZE (wanted_mode);
2254 newmem = gen_rtx_MEM (wanted_mode,
2255 plus_constant (XEXP (tem, 0),
2257 MEM_COPY_ATTRIBUTES (newmem, tem);
2259 /* Make the change and see if the insn remains valid. */
2260 INSN_CODE (insn) = -1;
2261 XEXP (outerdest, 0) = newmem;
2262 XEXP (outerdest, 2) = GEN_INT (pos);
2264 if (recog_memoized (insn) >= 0)
2267 /* Otherwise, restore old position. XEXP (x, 0) will be
2269 XEXP (outerdest, 2) = old_pos;
2273 /* If we get here, the bit-field store doesn't allow memory
2274 or isn't located at a constant position. Load the value into
2275 a register, do the store, and put it back into memory. */
2277 tem1 = gen_reg_rtx (GET_MODE (tem));
2278 emit_insn_before (gen_move_insn (tem1, tem), insn);
2279 emit_insn_after (gen_move_insn (tem, tem1), insn);
2280 XEXP (outerdest, 0) = tem1;
2285 /* STRICT_LOW_PART is a no-op on memory references
2286 and it can cause combinations to be unrecognizable,
2289 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2290 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2292 /* A valid insn to copy VAR into or out of a register
2293 must be left alone, to avoid an infinite loop here.
2294 If the reference to VAR is by a subreg, fix that up,
2295 since SUBREG is not valid for a memref.
2296 Also fix up the address of the stack slot.
2298 Note that we must not try to recognize the insn until
2299 after we know that we have valid addresses and no
2300 (subreg (mem ...) ...) constructs, since these interfere
2301 with determining the validity of the insn. */
2303 if ((SET_SRC (x) == var
2304 || (GET_CODE (SET_SRC (x)) == SUBREG
2305 && SUBREG_REG (SET_SRC (x)) == var))
2306 && (GET_CODE (SET_DEST (x)) == REG
2307 || (GET_CODE (SET_DEST (x)) == SUBREG
2308 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2309 && GET_MODE (var) == promoted_mode
2310 && x == single_set (insn))
2314 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2315 if (replacement->new)
2316 SET_SRC (x) = replacement->new;
2317 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2318 SET_SRC (x) = replacement->new
2319 = fixup_memory_subreg (SET_SRC (x), insn, 0);
2321 SET_SRC (x) = replacement->new
2322 = fixup_stack_1 (SET_SRC (x), insn);
2324 if (recog_memoized (insn) >= 0)
2327 /* INSN is not valid, but we know that we want to
2328 copy SET_SRC (x) to SET_DEST (x) in some way. So
2329 we generate the move and see whether it requires more
2330 than one insn. If it does, we emit those insns and
2331 delete INSN. Otherwise, we an just replace the pattern
2332 of INSN; we have already verified above that INSN has
2333 no other function that to do X. */
2335 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2336 if (GET_CODE (pat) == SEQUENCE)
2338 emit_insn_after (pat, insn);
2339 PUT_CODE (insn, NOTE);
2340 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
2341 NOTE_SOURCE_FILE (insn) = 0;
2344 PATTERN (insn) = pat;
2349 if ((SET_DEST (x) == var
2350 || (GET_CODE (SET_DEST (x)) == SUBREG
2351 && SUBREG_REG (SET_DEST (x)) == var))
2352 && (GET_CODE (SET_SRC (x)) == REG
2353 || (GET_CODE (SET_SRC (x)) == SUBREG
2354 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2355 && GET_MODE (var) == promoted_mode
2356 && x == single_set (insn))
2360 if (GET_CODE (SET_DEST (x)) == SUBREG)
2361 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn, 0);
2363 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2365 if (recog_memoized (insn) >= 0)
2368 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2369 if (GET_CODE (pat) == SEQUENCE)
2371 emit_insn_after (pat, insn);
2372 PUT_CODE (insn, NOTE);
2373 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
2374 NOTE_SOURCE_FILE (insn) = 0;
2377 PATTERN (insn) = pat;
2382 /* Otherwise, storing into VAR must be handled specially
2383 by storing into a temporary and copying that into VAR
2384 with a new insn after this one. Note that this case
2385 will be used when storing into a promoted scalar since
2386 the insn will now have different modes on the input
2387 and output and hence will be invalid (except for the case
2388 of setting it to a constant, which does not need any
2389 change if it is valid). We generate extra code in that case,
2390 but combine.c will eliminate it. */
2395 rtx fixeddest = SET_DEST (x);
2397 /* STRICT_LOW_PART can be discarded, around a MEM. */
2398 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2399 fixeddest = XEXP (fixeddest, 0);
2400 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2401 if (GET_CODE (fixeddest) == SUBREG)
2403 fixeddest = fixup_memory_subreg (fixeddest, insn, 0);
2404 promoted_mode = GET_MODE (fixeddest);
2407 fixeddest = fixup_stack_1 (fixeddest, insn);
2409 temp = gen_reg_rtx (promoted_mode);
2411 emit_insn_after (gen_move_insn (fixeddest,
2412 gen_lowpart (GET_MODE (fixeddest),
2416 SET_DEST (x) = temp;
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 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements);
2431 else if (fmt[i] == 'E')
2434 for (j = 0; j < XVECLEN (x, i); j++)
2435 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2436 insn, replacements);
2441 /* Given X, an rtx of the form (SUBREG:m1 (MEM:m2 addr)),
2442 return an rtx (MEM:m1 newaddr) which is equivalent.
2443 If any insns must be emitted to compute NEWADDR, put them before INSN.
2445 UNCRITICAL nonzero means accept paradoxical subregs.
2446 This is used for subregs found inside REG_NOTES. */
2449 fixup_memory_subreg (x, insn, uncritical)
2454 int offset = SUBREG_WORD (x) * UNITS_PER_WORD;
2455 rtx addr = XEXP (SUBREG_REG (x), 0);
2456 enum machine_mode mode = GET_MODE (x);
2459 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2460 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))
2464 if (BYTES_BIG_ENDIAN)
2465 offset += (MIN (UNITS_PER_WORD, GET_MODE_SIZE (GET_MODE (SUBREG_REG (x))))
2466 - MIN (UNITS_PER_WORD, GET_MODE_SIZE (mode)));
2467 addr = plus_constant (addr, offset);
2468 if (!flag_force_addr && memory_address_p (mode, addr))
2469 /* Shortcut if no insns need be emitted. */
2470 return change_address (SUBREG_REG (x), mode, addr);
2472 result = change_address (SUBREG_REG (x), mode, addr);
2473 emit_insn_before (gen_sequence (), insn);
2478 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2479 Replace subexpressions of X in place.
2480 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2481 Otherwise return X, with its contents possibly altered.
2483 If any insns must be emitted to compute NEWADDR, put them before INSN.
2485 UNCRITICAL is as in fixup_memory_subreg. */
2488 walk_fixup_memory_subreg (x, insn, uncritical)
2493 register enum rtx_code code;
2494 register const char *fmt;
2500 code = GET_CODE (x);
2502 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2503 return fixup_memory_subreg (x, insn, uncritical);
2505 /* Nothing special about this RTX; fix its operands. */
2507 fmt = GET_RTX_FORMAT (code);
2508 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2511 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn, uncritical);
2512 else if (fmt[i] == 'E')
2515 for (j = 0; j < XVECLEN (x, i); j++)
2517 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn, uncritical);
2523 /* For each memory ref within X, if it refers to a stack slot
2524 with an out of range displacement, put the address in a temp register
2525 (emitting new insns before INSN to load these registers)
2526 and alter the memory ref to use that register.
2527 Replace each such MEM rtx with a copy, to avoid clobberage. */
2530 fixup_stack_1 (x, insn)
2535 register RTX_CODE code = GET_CODE (x);
2536 register const char *fmt;
2540 register rtx ad = XEXP (x, 0);
2541 /* If we have address of a stack slot but it's not valid
2542 (displacement is too large), compute the sum in a register. */
2543 if (GET_CODE (ad) == PLUS
2544 && GET_CODE (XEXP (ad, 0)) == REG
2545 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2546 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2547 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2548 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2549 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2551 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2552 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2553 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2554 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2557 if (memory_address_p (GET_MODE (x), ad))
2561 temp = copy_to_reg (ad);
2562 seq = gen_sequence ();
2564 emit_insn_before (seq, insn);
2565 return change_address (x, VOIDmode, temp);
2570 fmt = GET_RTX_FORMAT (code);
2571 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2574 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2575 else if (fmt[i] == 'E')
2578 for (j = 0; j < XVECLEN (x, i); j++)
2579 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2585 /* Optimization: a bit-field instruction whose field
2586 happens to be a byte or halfword in memory
2587 can be changed to a move instruction.
2589 We call here when INSN is an insn to examine or store into a bit-field.
2590 BODY is the SET-rtx to be altered.
2592 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2593 (Currently this is called only from function.c, and EQUIV_MEM
2597 optimize_bit_field (body, insn, equiv_mem)
2602 register rtx bitfield;
2605 enum machine_mode mode;
2607 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2608 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2609 bitfield = SET_DEST (body), destflag = 1;
2611 bitfield = SET_SRC (body), destflag = 0;
2613 /* First check that the field being stored has constant size and position
2614 and is in fact a byte or halfword suitably aligned. */
2616 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2617 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2618 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2620 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2622 register rtx memref = 0;
2624 /* Now check that the containing word is memory, not a register,
2625 and that it is safe to change the machine mode. */
2627 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2628 memref = XEXP (bitfield, 0);
2629 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2631 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2632 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2633 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2634 memref = SUBREG_REG (XEXP (bitfield, 0));
2635 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2637 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2638 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2641 && ! mode_dependent_address_p (XEXP (memref, 0))
2642 && ! MEM_VOLATILE_P (memref))
2644 /* Now adjust the address, first for any subreg'ing
2645 that we are now getting rid of,
2646 and then for which byte of the word is wanted. */
2648 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2651 /* Adjust OFFSET to count bits from low-address byte. */
2652 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2653 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2654 - offset - INTVAL (XEXP (bitfield, 1)));
2656 /* Adjust OFFSET to count bytes from low-address byte. */
2657 offset /= BITS_PER_UNIT;
2658 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2660 offset += SUBREG_WORD (XEXP (bitfield, 0)) * UNITS_PER_WORD;
2661 if (BYTES_BIG_ENDIAN)
2662 offset -= (MIN (UNITS_PER_WORD,
2663 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2664 - MIN (UNITS_PER_WORD,
2665 GET_MODE_SIZE (GET_MODE (memref))));
2669 memref = change_address (memref, mode,
2670 plus_constant (XEXP (memref, 0), offset));
2671 insns = get_insns ();
2673 emit_insns_before (insns, insn);
2675 /* Store this memory reference where
2676 we found the bit field reference. */
2680 validate_change (insn, &SET_DEST (body), memref, 1);
2681 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2683 rtx src = SET_SRC (body);
2684 while (GET_CODE (src) == SUBREG
2685 && SUBREG_WORD (src) == 0)
2686 src = SUBREG_REG (src);
2687 if (GET_MODE (src) != GET_MODE (memref))
2688 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2689 validate_change (insn, &SET_SRC (body), src, 1);
2691 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2692 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2693 /* This shouldn't happen because anything that didn't have
2694 one of these modes should have got converted explicitly
2695 and then referenced through a subreg.
2696 This is so because the original bit-field was
2697 handled by agg_mode and so its tree structure had
2698 the same mode that memref now has. */
2703 rtx dest = SET_DEST (body);
2705 while (GET_CODE (dest) == SUBREG
2706 && SUBREG_WORD (dest) == 0
2707 && (GET_MODE_CLASS (GET_MODE (dest))
2708 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2709 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2711 dest = SUBREG_REG (dest);
2713 validate_change (insn, &SET_DEST (body), dest, 1);
2715 if (GET_MODE (dest) == GET_MODE (memref))
2716 validate_change (insn, &SET_SRC (body), memref, 1);
2719 /* Convert the mem ref to the destination mode. */
2720 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2723 convert_move (newreg, memref,
2724 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2728 validate_change (insn, &SET_SRC (body), newreg, 1);
2732 /* See if we can convert this extraction or insertion into
2733 a simple move insn. We might not be able to do so if this
2734 was, for example, part of a PARALLEL.
2736 If we succeed, write out any needed conversions. If we fail,
2737 it is hard to guess why we failed, so don't do anything
2738 special; just let the optimization be suppressed. */
2740 if (apply_change_group () && seq)
2741 emit_insns_before (seq, insn);
2746 /* These routines are responsible for converting virtual register references
2747 to the actual hard register references once RTL generation is complete.
2749 The following four variables are used for communication between the
2750 routines. They contain the offsets of the virtual registers from their
2751 respective hard registers. */
2753 static int in_arg_offset;
2754 static int var_offset;
2755 static int dynamic_offset;
2756 static int out_arg_offset;
2757 static int cfa_offset;
2759 /* In most machines, the stack pointer register is equivalent to the bottom
2762 #ifndef STACK_POINTER_OFFSET
2763 #define STACK_POINTER_OFFSET 0
2766 /* If not defined, pick an appropriate default for the offset of dynamically
2767 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2768 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2770 #ifndef STACK_DYNAMIC_OFFSET
2772 /* The bottom of the stack points to the actual arguments. If
2773 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2774 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2775 stack space for register parameters is not pushed by the caller, but
2776 rather part of the fixed stack areas and hence not included in
2777 `current_function_outgoing_args_size'. Nevertheless, we must allow
2778 for it when allocating stack dynamic objects. */
2780 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2781 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2782 ((ACCUMULATE_OUTGOING_ARGS \
2783 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2784 + (STACK_POINTER_OFFSET)) \
2787 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2788 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2789 + (STACK_POINTER_OFFSET))
2793 /* On most machines, the CFA coincides with the first incoming parm. */
2795 #ifndef ARG_POINTER_CFA_OFFSET
2796 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2800 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just had
2801 its address taken. DECL is the decl for the object stored in the
2802 register, for later use if we do need to force REG into the stack.
2803 REG is overwritten by the MEM like in put_reg_into_stack. */
2806 gen_mem_addressof (reg, decl)
2810 tree type = TREE_TYPE (decl);
2811 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2814 /* If the original REG was a user-variable, then so is the REG whose
2815 address is being taken. Likewise for unchanging. */
2816 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2817 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2819 PUT_CODE (reg, MEM);
2820 PUT_MODE (reg, DECL_MODE (decl));
2822 MEM_VOLATILE_P (reg) = TREE_SIDE_EFFECTS (decl);
2823 MEM_SET_IN_STRUCT_P (reg, AGGREGATE_TYPE_P (type));
2824 MEM_ALIAS_SET (reg) = get_alias_set (decl);
2826 if (TREE_USED (decl) || DECL_INITIAL (decl) != 0)
2827 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), 0);
2832 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2835 flush_addressof (decl)
2838 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2839 && DECL_RTL (decl) != 0
2840 && GET_CODE (DECL_RTL (decl)) == MEM
2841 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2842 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2843 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2846 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2849 put_addressof_into_stack (r, ht)
2851 struct hash_table *ht;
2853 tree decl = ADDRESSOF_DECL (r);
2854 rtx reg = XEXP (r, 0);
2856 if (GET_CODE (reg) != REG)
2859 put_reg_into_stack (0, reg, TREE_TYPE (decl), GET_MODE (reg),
2861 (TREE_CODE (decl) != SAVE_EXPR
2862 && TREE_THIS_VOLATILE (decl)),
2863 ADDRESSOF_REGNO (r),
2865 || (TREE_CODE (decl) != SAVE_EXPR
2866 && DECL_INITIAL (decl) != 0)),
2870 /* List of replacements made below in purge_addressof_1 when creating
2871 bitfield insertions. */
2872 static rtx purge_bitfield_addressof_replacements;
2874 /* List of replacements made below in purge_addressof_1 for patterns
2875 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2876 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2877 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2878 enough in complex cases, e.g. when some field values can be
2879 extracted by usage MEM with narrower mode. */
2880 static rtx purge_addressof_replacements;
2882 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2883 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2884 the stack. If the function returns FALSE then the replacement could not
2888 purge_addressof_1 (loc, insn, force, store, ht)
2892 struct hash_table *ht;
2898 boolean result = true;
2900 /* Re-start here to avoid recursion in common cases. */
2907 code = GET_CODE (x);
2909 /* If we don't return in any of the cases below, we will recurse inside
2910 the RTX, which will normally result in any ADDRESSOF being forced into
2914 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1, ht);
2915 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0, ht);
2919 else if (code == ADDRESSOF && GET_CODE (XEXP (x, 0)) == MEM)
2921 /* We must create a copy of the rtx because it was created by
2922 overwriting a REG rtx which is always shared. */
2923 rtx sub = copy_rtx (XEXP (XEXP (x, 0), 0));
2926 if (validate_change (insn, loc, sub, 0)
2927 || validate_replace_rtx (x, sub, insn))
2931 sub = force_operand (sub, NULL_RTX);
2932 if (! validate_change (insn, loc, sub, 0)
2933 && ! validate_replace_rtx (x, sub, insn))
2936 insns = gen_sequence ();
2938 emit_insn_before (insns, insn);
2942 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
2944 rtx sub = XEXP (XEXP (x, 0), 0);
2947 if (GET_CODE (sub) == MEM)
2949 sub2 = gen_rtx_MEM (GET_MODE (x), copy_rtx (XEXP (sub, 0)));
2950 MEM_COPY_ATTRIBUTES (sub2, sub);
2953 else if (GET_CODE (sub) == REG
2954 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
2956 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
2958 int size_x, size_sub;
2962 /* When processing REG_NOTES look at the list of
2963 replacements done on the insn to find the register that X
2967 for (tem = purge_bitfield_addressof_replacements;
2969 tem = XEXP (XEXP (tem, 1), 1))
2970 if (rtx_equal_p (x, XEXP (tem, 0)))
2972 *loc = XEXP (XEXP (tem, 1), 0);
2976 /* See comment for purge_addressof_replacements. */
2977 for (tem = purge_addressof_replacements;
2979 tem = XEXP (XEXP (tem, 1), 1))
2980 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
2982 rtx z = XEXP (XEXP (tem, 1), 0);
2984 if (GET_MODE (x) == GET_MODE (z)
2985 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
2986 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
2989 /* It can happen that the note may speak of things
2990 in a wider (or just different) mode than the
2991 code did. This is especially true of
2994 if (GET_CODE (z) == SUBREG && SUBREG_WORD (z) == 0)
2997 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
2998 && (GET_MODE_SIZE (GET_MODE (x))
2999 > GET_MODE_SIZE (GET_MODE (z))))
3001 /* This can occur as a result in invalid
3002 pointer casts, e.g. float f; ...
3003 *(long long int *)&f.
3004 ??? We could emit a warning here, but
3005 without a line number that wouldn't be
3007 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
3010 z = gen_lowpart (GET_MODE (x), z);
3016 /* Sometimes we may not be able to find the replacement. For
3017 example when the original insn was a MEM in a wider mode,
3018 and the note is part of a sign extension of a narrowed
3019 version of that MEM. Gcc testcase compile/990829-1.c can
3020 generate an example of this siutation. Rather than complain
3021 we return false, which will prompt our caller to remove the
3026 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3027 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3029 /* Don't even consider working with paradoxical subregs,
3030 or the moral equivalent seen here. */
3031 if (size_x <= size_sub
3032 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3034 /* Do a bitfield insertion to mirror what would happen
3041 rtx p = PREV_INSN (insn);
3044 val = gen_reg_rtx (GET_MODE (x));
3045 if (! validate_change (insn, loc, val, 0))
3047 /* Discard the current sequence and put the
3048 ADDRESSOF on stack. */
3052 seq = gen_sequence ();
3054 emit_insn_before (seq, insn);
3055 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3059 store_bit_field (sub, size_x, 0, GET_MODE (x),
3060 val, GET_MODE_SIZE (GET_MODE (sub)),
3061 GET_MODE_ALIGNMENT (GET_MODE (sub)));
3063 /* Make sure to unshare any shared rtl that store_bit_field
3064 might have created. */
3065 unshare_all_rtl_again (get_insns ());
3067 seq = gen_sequence ();
3069 p = emit_insn_after (seq, insn);
3070 if (NEXT_INSN (insn))
3071 compute_insns_for_mem (NEXT_INSN (insn),
3072 p ? NEXT_INSN (p) : NULL_RTX,
3077 rtx p = PREV_INSN (insn);
3080 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3081 GET_MODE (x), GET_MODE (x),
3082 GET_MODE_SIZE (GET_MODE (sub)),
3083 GET_MODE_SIZE (GET_MODE (sub)));
3085 if (! validate_change (insn, loc, val, 0))
3087 /* Discard the current sequence and put the
3088 ADDRESSOF on stack. */
3093 seq = gen_sequence ();
3095 emit_insn_before (seq, insn);
3096 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3100 /* Remember the replacement so that the same one can be done
3101 on the REG_NOTES. */
3102 purge_bitfield_addressof_replacements
3103 = gen_rtx_EXPR_LIST (VOIDmode, x,
3106 purge_bitfield_addressof_replacements));
3108 /* We replaced with a reg -- all done. */
3113 else if (validate_change (insn, loc, sub, 0))
3115 /* Remember the replacement so that the same one can be done
3116 on the REG_NOTES. */
3117 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3121 for (tem = purge_addressof_replacements;
3123 tem = XEXP (XEXP (tem, 1), 1))
3124 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3126 XEXP (XEXP (tem, 1), 0) = sub;
3129 purge_addressof_replacements
3130 = gen_rtx (EXPR_LIST, VOIDmode, XEXP (x, 0),
3131 gen_rtx_EXPR_LIST (VOIDmode, sub,
3132 purge_addressof_replacements));
3138 /* else give up and put it into the stack */
3141 else if (code == ADDRESSOF)
3143 put_addressof_into_stack (x, ht);
3146 else if (code == SET)
3148 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1, ht);
3149 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0, ht);
3153 /* Scan all subexpressions. */
3154 fmt = GET_RTX_FORMAT (code);
3155 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3158 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0, ht);
3159 else if (*fmt == 'E')
3160 for (j = 0; j < XVECLEN (x, i); j++)
3161 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0, ht);
3167 /* Return a new hash table entry in HT. */
3169 static struct hash_entry *
3170 insns_for_mem_newfunc (he, ht, k)
3171 struct hash_entry *he;
3172 struct hash_table *ht;
3173 hash_table_key k ATTRIBUTE_UNUSED;
3175 struct insns_for_mem_entry *ifmhe;
3179 ifmhe = ((struct insns_for_mem_entry *)
3180 hash_allocate (ht, sizeof (struct insns_for_mem_entry)));
3181 ifmhe->insns = NULL_RTX;
3186 /* Return a hash value for K, a REG. */
3188 static unsigned long
3189 insns_for_mem_hash (k)
3192 /* K is really a RTX. Just use the address as the hash value. */
3193 return (unsigned long) k;
3196 /* Return non-zero if K1 and K2 (two REGs) are the same. */
3199 insns_for_mem_comp (k1, k2)
3206 struct insns_for_mem_walk_info {
3207 /* The hash table that we are using to record which INSNs use which
3209 struct hash_table *ht;
3211 /* The INSN we are currently proessing. */
3214 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3215 to find the insns that use the REGs in the ADDRESSOFs. */
3219 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3220 that might be used in an ADDRESSOF expression, record this INSN in
3221 the hash table given by DATA (which is really a pointer to an
3222 insns_for_mem_walk_info structure). */
3225 insns_for_mem_walk (r, data)
3229 struct insns_for_mem_walk_info *ifmwi
3230 = (struct insns_for_mem_walk_info *) data;
3232 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3233 && GET_CODE (XEXP (*r, 0)) == REG)
3234 hash_lookup (ifmwi->ht, XEXP (*r, 0), /*create=*/1, /*copy=*/0);
3235 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3237 /* Lookup this MEM in the hashtable, creating it if necessary. */
3238 struct insns_for_mem_entry *ifme
3239 = (struct insns_for_mem_entry *) hash_lookup (ifmwi->ht,
3244 /* If we have not already recorded this INSN, do so now. Since
3245 we process the INSNs in order, we know that if we have
3246 recorded it it must be at the front of the list. */
3247 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3249 /* We do the allocation on the same obstack as is used for
3250 the hash table since this memory will not be used once
3251 the hash table is deallocated. */
3252 push_obstacks (&ifmwi->ht->memory, &ifmwi->ht->memory);
3253 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3262 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3263 which REGs in HT. */
3266 compute_insns_for_mem (insns, last_insn, ht)
3269 struct hash_table *ht;
3272 struct insns_for_mem_walk_info ifmwi;
3275 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3276 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3280 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3284 /* Helper function for purge_addressof called through for_each_rtx.
3285 Returns true iff the rtl is an ADDRESSOF. */
3287 is_addressof (rtl, data)
3289 void * data ATTRIBUTE_UNUSED;
3291 return GET_CODE (* rtl) == ADDRESSOF;
3294 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3295 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3299 purge_addressof (insns)
3303 struct hash_table ht;
3305 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3306 requires a fixup pass over the instruction stream to correct
3307 INSNs that depended on the REG being a REG, and not a MEM. But,
3308 these fixup passes are slow. Furthermore, most MEMs are not
3309 mentioned in very many instructions. So, we speed up the process
3310 by pre-calculating which REGs occur in which INSNs; that allows
3311 us to perform the fixup passes much more quickly. */
3312 hash_table_init (&ht,
3313 insns_for_mem_newfunc,
3315 insns_for_mem_comp);
3316 compute_insns_for_mem (insns, NULL_RTX, &ht);
3318 for (insn = insns; insn; insn = NEXT_INSN (insn))
3319 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3320 || GET_CODE (insn) == CALL_INSN)
3322 if (! purge_addressof_1 (&PATTERN (insn), insn,
3323 asm_noperands (PATTERN (insn)) > 0, 0, &ht))
3324 /* If we could not replace the ADDRESSOFs in the insn,
3325 something is wrong. */
3328 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, &ht))
3330 /* If we could not replace the ADDRESSOFs in the insn's notes,
3331 we can just remove the offending notes instead. */
3334 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3336 /* If we find a REG_RETVAL note then the insn is a libcall.
3337 Such insns must have REG_EQUAL notes as well, in order
3338 for later passes of the compiler to work. So it is not
3339 safe to delete the notes here, and instead we abort. */
3340 if (REG_NOTE_KIND (note) == REG_RETVAL)
3342 if (for_each_rtx (& note, is_addressof, NULL))
3343 remove_note (insn, note);
3349 hash_table_free (&ht);
3350 purge_bitfield_addressof_replacements = 0;
3351 purge_addressof_replacements = 0;
3353 /* REGs are shared. purge_addressof will destructively replace a REG
3354 with a MEM, which creates shared MEMs.
3356 Unfortunately, the children of put_reg_into_stack assume that MEMs
3357 referring to the same stack slot are shared (fixup_var_refs and
3358 the associated hash table code).
3360 So, we have to do another unsharing pass after we have flushed any
3361 REGs that had their address taken into the stack.
3363 It may be worth tracking whether or not we converted any REGs into
3364 MEMs to avoid this overhead when it is not needed. */
3365 unshare_all_rtl_again (get_insns ());
3368 /* Pass through the INSNS of function FNDECL and convert virtual register
3369 references to hard register references. */
3372 instantiate_virtual_regs (fndecl, insns)
3379 /* Compute the offsets to use for this function. */
3380 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3381 var_offset = STARTING_FRAME_OFFSET;
3382 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3383 out_arg_offset = STACK_POINTER_OFFSET;
3384 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl);
3386 /* Scan all variables and parameters of this function. For each that is
3387 in memory, instantiate all virtual registers if the result is a valid
3388 address. If not, we do it later. That will handle most uses of virtual
3389 regs on many machines. */
3390 instantiate_decls (fndecl, 1);
3392 /* Initialize recognition, indicating that volatile is OK. */
3395 /* Scan through all the insns, instantiating every virtual register still
3397 for (insn = insns; insn; insn = NEXT_INSN (insn))
3398 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3399 || GET_CODE (insn) == CALL_INSN)
3401 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3402 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3405 /* Instantiate the stack slots for the parm registers, for later use in
3406 addressof elimination. */
3407 for (i = 0; i < max_parm_reg; ++i)
3408 if (parm_reg_stack_loc[i])
3409 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3411 /* Now instantiate the remaining register equivalences for debugging info.
3412 These will not be valid addresses. */
3413 instantiate_decls (fndecl, 0);
3415 /* Indicate that, from now on, assign_stack_local should use
3416 frame_pointer_rtx. */
3417 virtuals_instantiated = 1;
3420 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3421 all virtual registers in their DECL_RTL's.
3423 If VALID_ONLY, do this only if the resulting address is still valid.
3424 Otherwise, always do it. */
3427 instantiate_decls (fndecl, valid_only)
3433 if (DECL_SAVED_INSNS (fndecl))
3434 /* When compiling an inline function, the obstack used for
3435 rtl allocation is the maybepermanent_obstack. Calling
3436 `resume_temporary_allocation' switches us back to that
3437 obstack while we process this function's parameters. */
3438 resume_temporary_allocation ();
3440 /* Process all parameters of the function. */
3441 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3443 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3445 instantiate_decl (DECL_RTL (decl), size, valid_only);
3447 /* If the parameter was promoted, then the incoming RTL mode may be
3448 larger than the declared type size. We must use the larger of
3450 size = MAX (GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl))), size);
3451 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3454 /* Now process all variables defined in the function or its subblocks. */
3455 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3457 if (DECL_INLINE (fndecl) || DECL_DEFER_OUTPUT (fndecl))
3459 /* Save all rtl allocated for this function by raising the
3460 high-water mark on the maybepermanent_obstack. */
3462 /* All further rtl allocation is now done in the current_obstack. */
3463 rtl_in_current_obstack ();
3467 /* Subroutine of instantiate_decls: Process all decls in the given
3468 BLOCK node and all its subblocks. */
3471 instantiate_decls_1 (let, valid_only)
3477 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3478 instantiate_decl (DECL_RTL (t), int_size_in_bytes (TREE_TYPE (t)),
3481 /* Process all subblocks. */
3482 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3483 instantiate_decls_1 (t, valid_only);
3486 /* Subroutine of the preceding procedures: Given RTL representing a
3487 decl and the size of the object, do any instantiation required.
3489 If VALID_ONLY is non-zero, it means that the RTL should only be
3490 changed if the new address is valid. */
3493 instantiate_decl (x, size, valid_only)
3498 enum machine_mode mode;
3501 /* If this is not a MEM, no need to do anything. Similarly if the
3502 address is a constant or a register that is not a virtual register. */
3504 if (x == 0 || GET_CODE (x) != MEM)
3508 if (CONSTANT_P (addr)
3509 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3510 || (GET_CODE (addr) == REG
3511 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3512 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3515 /* If we should only do this if the address is valid, copy the address.
3516 We need to do this so we can undo any changes that might make the
3517 address invalid. This copy is unfortunate, but probably can't be
3521 addr = copy_rtx (addr);
3523 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3525 if (valid_only && size >= 0)
3527 unsigned HOST_WIDE_INT decl_size = size;
3529 /* Now verify that the resulting address is valid for every integer or
3530 floating-point mode up to and including SIZE bytes long. We do this
3531 since the object might be accessed in any mode and frame addresses
3534 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3535 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3536 mode = GET_MODE_WIDER_MODE (mode))
3537 if (! memory_address_p (mode, addr))
3540 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3541 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3542 mode = GET_MODE_WIDER_MODE (mode))
3543 if (! memory_address_p (mode, addr))
3547 /* Put back the address now that we have updated it and we either know
3548 it is valid or we don't care whether it is valid. */
3553 /* Given a pointer to a piece of rtx and an optional pointer to the
3554 containing object, instantiate any virtual registers present in it.
3556 If EXTRA_INSNS, we always do the replacement and generate
3557 any extra insns before OBJECT. If it zero, we do nothing if replacement
3560 Return 1 if we either had nothing to do or if we were able to do the
3561 needed replacement. Return 0 otherwise; we only return zero if
3562 EXTRA_INSNS is zero.
3564 We first try some simple transformations to avoid the creation of extra
3568 instantiate_virtual_regs_1 (loc, object, extra_insns)
3576 HOST_WIDE_INT offset = 0;
3582 /* Re-start here to avoid recursion in common cases. */
3589 code = GET_CODE (x);
3591 /* Check for some special cases. */
3608 /* We are allowed to set the virtual registers. This means that
3609 the actual register should receive the source minus the
3610 appropriate offset. This is used, for example, in the handling
3611 of non-local gotos. */
3612 if (SET_DEST (x) == virtual_incoming_args_rtx)
3613 new = arg_pointer_rtx, offset = - in_arg_offset;
3614 else if (SET_DEST (x) == virtual_stack_vars_rtx)
3615 new = frame_pointer_rtx, offset = - var_offset;
3616 else if (SET_DEST (x) == virtual_stack_dynamic_rtx)
3617 new = stack_pointer_rtx, offset = - dynamic_offset;
3618 else if (SET_DEST (x) == virtual_outgoing_args_rtx)
3619 new = stack_pointer_rtx, offset = - out_arg_offset;
3620 else if (SET_DEST (x) == virtual_cfa_rtx)
3621 new = arg_pointer_rtx, offset = - cfa_offset;
3625 rtx src = SET_SRC (x);
3627 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3629 /* The only valid sources here are PLUS or REG. Just do
3630 the simplest possible thing to handle them. */
3631 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3635 if (GET_CODE (src) != REG)
3636 temp = force_operand (src, NULL_RTX);
3639 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3643 emit_insns_before (seq, object);
3646 if (! validate_change (object, &SET_SRC (x), temp, 0)
3653 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3658 /* Handle special case of virtual register plus constant. */
3659 if (CONSTANT_P (XEXP (x, 1)))
3661 rtx old, new_offset;
3663 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3664 if (GET_CODE (XEXP (x, 0)) == PLUS)
3666 rtx inner = XEXP (XEXP (x, 0), 0);
3668 if (inner == virtual_incoming_args_rtx)
3669 new = arg_pointer_rtx, offset = in_arg_offset;
3670 else if (inner == virtual_stack_vars_rtx)
3671 new = frame_pointer_rtx, offset = var_offset;
3672 else if (inner == virtual_stack_dynamic_rtx)
3673 new = stack_pointer_rtx, offset = dynamic_offset;
3674 else if (inner == virtual_outgoing_args_rtx)
3675 new = stack_pointer_rtx, offset = out_arg_offset;
3676 else if (inner == virtual_cfa_rtx)
3677 new = arg_pointer_rtx, offset = cfa_offset;
3684 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3686 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3689 else if (XEXP (x, 0) == virtual_incoming_args_rtx)
3690 new = arg_pointer_rtx, offset = in_arg_offset;
3691 else if (XEXP (x, 0) == virtual_stack_vars_rtx)
3692 new = frame_pointer_rtx, offset = var_offset;
3693 else if (XEXP (x, 0) == virtual_stack_dynamic_rtx)
3694 new = stack_pointer_rtx, offset = dynamic_offset;
3695 else if (XEXP (x, 0) == virtual_outgoing_args_rtx)
3696 new = stack_pointer_rtx, offset = out_arg_offset;
3697 else if (XEXP (x, 0) == virtual_cfa_rtx)
3698 new = arg_pointer_rtx, offset = cfa_offset;
3701 /* We know the second operand is a constant. Unless the
3702 first operand is a REG (which has been already checked),
3703 it needs to be checked. */
3704 if (GET_CODE (XEXP (x, 0)) != REG)
3712 new_offset = plus_constant (XEXP (x, 1), offset);
3714 /* If the new constant is zero, try to replace the sum with just
3716 if (new_offset == const0_rtx
3717 && validate_change (object, loc, new, 0))
3720 /* Next try to replace the register and new offset.
3721 There are two changes to validate here and we can't assume that
3722 in the case of old offset equals new just changing the register
3723 will yield a valid insn. In the interests of a little efficiency,
3724 however, we only call validate change once (we don't queue up the
3725 changes and then call apply_change_group). */
3729 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3730 : (XEXP (x, 0) = new,
3731 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3739 /* Otherwise copy the new constant into a register and replace
3740 constant with that register. */
3741 temp = gen_reg_rtx (Pmode);
3743 if (validate_change (object, &XEXP (x, 1), temp, 0))
3744 emit_insn_before (gen_move_insn (temp, new_offset), object);
3747 /* If that didn't work, replace this expression with a
3748 register containing the sum. */
3751 new = gen_rtx_PLUS (Pmode, new, new_offset);
3754 temp = force_operand (new, NULL_RTX);
3758 emit_insns_before (seq, object);
3759 if (! validate_change (object, loc, temp, 0)
3760 && ! validate_replace_rtx (x, temp, object))
3768 /* Fall through to generic two-operand expression case. */
3774 case DIV: case UDIV:
3775 case MOD: case UMOD:
3776 case AND: case IOR: case XOR:
3777 case ROTATERT: case ROTATE:
3778 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3780 case GE: case GT: case GEU: case GTU:
3781 case LE: case LT: case LEU: case LTU:
3782 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3783 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3788 /* Most cases of MEM that convert to valid addresses have already been
3789 handled by our scan of decls. The only special handling we
3790 need here is to make a copy of the rtx to ensure it isn't being
3791 shared if we have to change it to a pseudo.
3793 If the rtx is a simple reference to an address via a virtual register,
3794 it can potentially be shared. In such cases, first try to make it
3795 a valid address, which can also be shared. Otherwise, copy it and
3798 First check for common cases that need no processing. These are
3799 usually due to instantiation already being done on a previous instance
3803 if (CONSTANT_ADDRESS_P (temp)
3804 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3805 || temp == arg_pointer_rtx
3807 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3808 || temp == hard_frame_pointer_rtx
3810 || temp == frame_pointer_rtx)
3813 if (GET_CODE (temp) == PLUS
3814 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3815 && (XEXP (temp, 0) == frame_pointer_rtx
3816 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3817 || XEXP (temp, 0) == hard_frame_pointer_rtx
3819 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3820 || XEXP (temp, 0) == arg_pointer_rtx
3825 if (temp == virtual_stack_vars_rtx
3826 || temp == virtual_incoming_args_rtx
3827 || (GET_CODE (temp) == PLUS
3828 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3829 && (XEXP (temp, 0) == virtual_stack_vars_rtx
3830 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
3832 /* This MEM may be shared. If the substitution can be done without
3833 the need to generate new pseudos, we want to do it in place
3834 so all copies of the shared rtx benefit. The call below will
3835 only make substitutions if the resulting address is still
3838 Note that we cannot pass X as the object in the recursive call
3839 since the insn being processed may not allow all valid
3840 addresses. However, if we were not passed on object, we can
3841 only modify X without copying it if X will have a valid
3844 ??? Also note that this can still lose if OBJECT is an insn that
3845 has less restrictions on an address that some other insn.
3846 In that case, we will modify the shared address. This case
3847 doesn't seem very likely, though. One case where this could
3848 happen is in the case of a USE or CLOBBER reference, but we
3849 take care of that below. */
3851 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
3852 object ? object : x, 0))
3855 /* Otherwise make a copy and process that copy. We copy the entire
3856 RTL expression since it might be a PLUS which could also be
3858 *loc = x = copy_rtx (x);
3861 /* Fall through to generic unary operation case. */
3863 case STRICT_LOW_PART:
3865 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
3866 case SIGN_EXTEND: case ZERO_EXTEND:
3867 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
3868 case FLOAT: case FIX:
3869 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
3873 /* These case either have just one operand or we know that we need not
3874 check the rest of the operands. */
3880 /* If the operand is a MEM, see if the change is a valid MEM. If not,
3881 go ahead and make the invalid one, but do it to a copy. For a REG,
3882 just make the recursive call, since there's no chance of a problem. */
3884 if ((GET_CODE (XEXP (x, 0)) == MEM
3885 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
3887 || (GET_CODE (XEXP (x, 0)) == REG
3888 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
3891 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
3896 /* Try to replace with a PLUS. If that doesn't work, compute the sum
3897 in front of this insn and substitute the temporary. */
3898 if (x == virtual_incoming_args_rtx)
3899 new = arg_pointer_rtx, offset = in_arg_offset;
3900 else if (x == virtual_stack_vars_rtx)
3901 new = frame_pointer_rtx, offset = var_offset;
3902 else if (x == virtual_stack_dynamic_rtx)
3903 new = stack_pointer_rtx, offset = dynamic_offset;
3904 else if (x == virtual_outgoing_args_rtx)
3905 new = stack_pointer_rtx, offset = out_arg_offset;
3906 else if (x == virtual_cfa_rtx)
3907 new = arg_pointer_rtx, offset = cfa_offset;
3911 temp = plus_constant (new, offset);
3912 if (!validate_change (object, loc, temp, 0))
3918 temp = force_operand (temp, NULL_RTX);
3922 emit_insns_before (seq, object);
3923 if (! validate_change (object, loc, temp, 0)
3924 && ! validate_replace_rtx (x, temp, object))
3932 if (GET_CODE (XEXP (x, 0)) == REG)
3935 else if (GET_CODE (XEXP (x, 0)) == MEM)
3937 /* If we have a (addressof (mem ..)), do any instantiation inside
3938 since we know we'll be making the inside valid when we finally
3939 remove the ADDRESSOF. */
3940 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
3949 /* Scan all subexpressions. */
3950 fmt = GET_RTX_FORMAT (code);
3951 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3954 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
3957 else if (*fmt == 'E')
3958 for (j = 0; j < XVECLEN (x, i); j++)
3959 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
3966 /* Optimization: assuming this function does not receive nonlocal gotos,
3967 delete the handlers for such, as well as the insns to establish
3968 and disestablish them. */
3974 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3976 /* Delete the handler by turning off the flag that would
3977 prevent jump_optimize from deleting it.
3978 Also permit deletion of the nonlocal labels themselves
3979 if nothing local refers to them. */
3980 if (GET_CODE (insn) == CODE_LABEL)
3984 LABEL_PRESERVE_P (insn) = 0;
3986 /* Remove it from the nonlocal_label list, to avoid confusing
3988 for (t = nonlocal_labels, last_t = 0; t;
3989 last_t = t, t = TREE_CHAIN (t))
3990 if (DECL_RTL (TREE_VALUE (t)) == insn)
3995 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
3997 TREE_CHAIN (last_t) = TREE_CHAIN (t);
4000 if (GET_CODE (insn) == INSN)
4004 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
4005 if (reg_mentioned_p (t, PATTERN (insn)))
4011 || (nonlocal_goto_stack_level != 0
4012 && reg_mentioned_p (nonlocal_goto_stack_level,
4022 return max_parm_reg;
4025 /* Return the first insn following those generated by `assign_parms'. */
4028 get_first_nonparm_insn ()
4031 return NEXT_INSN (last_parm_insn);
4032 return get_insns ();
4035 /* Return the first NOTE_INSN_BLOCK_BEG note in the function.
4036 Crash if there is none. */
4039 get_first_block_beg ()
4041 register rtx searcher;
4042 register rtx insn = get_first_nonparm_insn ();
4044 for (searcher = insn; searcher; searcher = NEXT_INSN (searcher))
4045 if (GET_CODE (searcher) == NOTE
4046 && NOTE_LINE_NUMBER (searcher) == NOTE_INSN_BLOCK_BEG)
4049 abort (); /* Invalid call to this function. (See comments above.) */
4053 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4054 This means a type for which function calls must pass an address to the
4055 function or get an address back from the function.
4056 EXP may be a type node or an expression (whose type is tested). */
4059 aggregate_value_p (exp)
4062 int i, regno, nregs;
4065 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4067 if (TREE_CODE (type) == VOID_TYPE)
4069 if (RETURN_IN_MEMORY (type))
4071 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4072 and thus can't be returned in registers. */
4073 if (TREE_ADDRESSABLE (type))
4075 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4077 /* Make sure we have suitable call-clobbered regs to return
4078 the value in; if not, we must return it in memory. */
4079 reg = hard_function_value (type, 0, 0);
4081 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4083 if (GET_CODE (reg) != REG)
4086 regno = REGNO (reg);
4087 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
4088 for (i = 0; i < nregs; i++)
4089 if (! call_used_regs[regno + i])
4094 /* Assign RTL expressions to the function's parameters.
4095 This may involve copying them into registers and using
4096 those registers as the RTL for them. */
4099 assign_parms (fndecl)
4103 register rtx entry_parm = 0;
4104 register rtx stack_parm = 0;
4105 CUMULATIVE_ARGS args_so_far;
4106 enum machine_mode promoted_mode, passed_mode;
4107 enum machine_mode nominal_mode, promoted_nominal_mode;
4109 /* Total space needed so far for args on the stack,
4110 given as a constant and a tree-expression. */
4111 struct args_size stack_args_size;
4112 tree fntype = TREE_TYPE (fndecl);
4113 tree fnargs = DECL_ARGUMENTS (fndecl);
4114 /* This is used for the arg pointer when referring to stack args. */
4115 rtx internal_arg_pointer;
4116 /* This is a dummy PARM_DECL that we used for the function result if
4117 the function returns a structure. */
4118 tree function_result_decl = 0;
4119 #ifdef SETUP_INCOMING_VARARGS
4120 int varargs_setup = 0;
4122 rtx conversion_insns = 0;
4123 struct args_size alignment_pad;
4125 /* Nonzero if the last arg is named `__builtin_va_alist',
4126 which is used on some machines for old-fashioned non-ANSI varargs.h;
4127 this should be stuck onto the stack as if it had arrived there. */
4129 = (current_function_varargs
4131 && (parm = tree_last (fnargs)) != 0
4133 && (! strcmp (IDENTIFIER_POINTER (DECL_NAME (parm)),
4134 "__builtin_va_alist")));
4136 /* Nonzero if function takes extra anonymous args.
4137 This means the last named arg must be on the stack
4138 right before the anonymous ones. */
4140 = (TYPE_ARG_TYPES (fntype) != 0
4141 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4142 != void_type_node));
4144 current_function_stdarg = stdarg;
4146 /* If the reg that the virtual arg pointer will be translated into is
4147 not a fixed reg or is the stack pointer, make a copy of the virtual
4148 arg pointer, and address parms via the copy. The frame pointer is
4149 considered fixed even though it is not marked as such.
4151 The second time through, simply use ap to avoid generating rtx. */
4153 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4154 || ! (fixed_regs[ARG_POINTER_REGNUM]
4155 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4156 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4158 internal_arg_pointer = virtual_incoming_args_rtx;
4159 current_function_internal_arg_pointer = internal_arg_pointer;
4161 stack_args_size.constant = 0;
4162 stack_args_size.var = 0;
4164 /* If struct value address is treated as the first argument, make it so. */
4165 if (aggregate_value_p (DECL_RESULT (fndecl))
4166 && ! current_function_returns_pcc_struct
4167 && struct_value_incoming_rtx == 0)
4169 tree type = build_pointer_type (TREE_TYPE (fntype));
4171 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4173 DECL_ARG_TYPE (function_result_decl) = type;
4174 TREE_CHAIN (function_result_decl) = fnargs;
4175 fnargs = function_result_decl;
4178 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4179 parm_reg_stack_loc = (rtx *) xcalloc (max_parm_reg, sizeof (rtx));
4181 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4182 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4184 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, 0);
4187 /* We haven't yet found an argument that we must push and pretend the
4189 current_function_pretend_args_size = 0;
4191 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4193 struct args_size stack_offset;
4194 struct args_size arg_size;
4195 int passed_pointer = 0;
4196 int did_conversion = 0;
4197 tree passed_type = DECL_ARG_TYPE (parm);
4198 tree nominal_type = TREE_TYPE (parm);
4201 /* Set LAST_NAMED if this is last named arg before some
4203 int last_named = ((TREE_CHAIN (parm) == 0
4204 || DECL_NAME (TREE_CHAIN (parm)) == 0)
4205 && (stdarg || current_function_varargs));
4206 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4207 most machines, if this is a varargs/stdarg function, then we treat
4208 the last named arg as if it were anonymous too. */
4209 int named_arg = STRICT_ARGUMENT_NAMING ? 1 : ! last_named;
4211 if (TREE_TYPE (parm) == error_mark_node
4212 /* This can happen after weird syntax errors
4213 or if an enum type is defined among the parms. */
4214 || TREE_CODE (parm) != PARM_DECL
4215 || passed_type == NULL)
4217 DECL_INCOMING_RTL (parm) = DECL_RTL (parm)
4218 = gen_rtx_MEM (BLKmode, const0_rtx);
4219 TREE_USED (parm) = 1;
4223 /* For varargs.h function, save info about regs and stack space
4224 used by the individual args, not including the va_alist arg. */
4225 if (hide_last_arg && last_named)
4226 current_function_args_info = args_so_far;
4228 /* Find mode of arg as it is passed, and mode of arg
4229 as it should be during execution of this function. */
4230 passed_mode = TYPE_MODE (passed_type);
4231 nominal_mode = TYPE_MODE (nominal_type);
4233 /* If the parm's mode is VOID, its value doesn't matter,
4234 and avoid the usual things like emit_move_insn that could crash. */
4235 if (nominal_mode == VOIDmode)
4237 DECL_INCOMING_RTL (parm) = DECL_RTL (parm) = const0_rtx;
4241 /* If the parm is to be passed as a transparent union, use the
4242 type of the first field for the tests below. We have already
4243 verified that the modes are the same. */
4244 if (DECL_TRANSPARENT_UNION (parm)
4245 || (TREE_CODE (passed_type) == UNION_TYPE
4246 && TYPE_TRANSPARENT_UNION (passed_type)))
4247 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4249 /* See if this arg was passed by invisible reference. It is if
4250 it is an object whose size depends on the contents of the
4251 object itself or if the machine requires these objects be passed
4254 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
4255 && contains_placeholder_p (TYPE_SIZE (passed_type)))
4256 || TREE_ADDRESSABLE (passed_type)
4257 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4258 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4259 passed_type, named_arg)
4263 passed_type = nominal_type = build_pointer_type (passed_type);
4265 passed_mode = nominal_mode = Pmode;
4268 promoted_mode = passed_mode;
4270 #ifdef PROMOTE_FUNCTION_ARGS
4271 /* Compute the mode in which the arg is actually extended to. */
4272 unsignedp = TREE_UNSIGNED (passed_type);
4273 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4276 /* Let machine desc say which reg (if any) the parm arrives in.
4277 0 means it arrives on the stack. */
4278 #ifdef FUNCTION_INCOMING_ARG
4279 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4280 passed_type, named_arg);
4282 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4283 passed_type, named_arg);
4286 if (entry_parm == 0)
4287 promoted_mode = passed_mode;
4289 #ifdef SETUP_INCOMING_VARARGS
4290 /* If this is the last named parameter, do any required setup for
4291 varargs or stdargs. We need to know about the case of this being an
4292 addressable type, in which case we skip the registers it
4293 would have arrived in.
4295 For stdargs, LAST_NAMED will be set for two parameters, the one that
4296 is actually the last named, and the dummy parameter. We only
4297 want to do this action once.
4299 Also, indicate when RTL generation is to be suppressed. */
4300 if (last_named && !varargs_setup)
4302 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
4303 current_function_pretend_args_size, 0);
4308 /* Determine parm's home in the stack,
4309 in case it arrives in the stack or we should pretend it did.
4311 Compute the stack position and rtx where the argument arrives
4314 There is one complexity here: If this was a parameter that would
4315 have been passed in registers, but wasn't only because it is
4316 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4317 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4318 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4319 0 as it was the previous time. */
4321 pretend_named = named_arg || PRETEND_OUTGOING_VARARGS_NAMED;
4322 locate_and_pad_parm (promoted_mode, passed_type,
4323 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4326 #ifdef FUNCTION_INCOMING_ARG
4327 FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4329 pretend_named) != 0,
4331 FUNCTION_ARG (args_so_far, promoted_mode,
4333 pretend_named) != 0,
4336 fndecl, &stack_args_size, &stack_offset, &arg_size,
4340 rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
4342 if (offset_rtx == const0_rtx)
4343 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4345 stack_parm = gen_rtx_MEM (promoted_mode,
4346 gen_rtx_PLUS (Pmode,
4347 internal_arg_pointer,
4350 set_mem_attributes (stack_parm, parm, 1);
4353 /* If this parameter was passed both in registers and in the stack,
4354 use the copy on the stack. */
4355 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4358 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4359 /* If this parm was passed part in regs and part in memory,
4360 pretend it arrived entirely in memory
4361 by pushing the register-part onto the stack.
4363 In the special case of a DImode or DFmode that is split,
4364 we could put it together in a pseudoreg directly,
4365 but for now that's not worth bothering with. */
4369 int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4370 passed_type, named_arg);
4374 current_function_pretend_args_size
4375 = (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
4376 / (PARM_BOUNDARY / BITS_PER_UNIT)
4377 * (PARM_BOUNDARY / BITS_PER_UNIT));
4379 /* Handle calls that pass values in multiple non-contiguous
4380 locations. The Irix 6 ABI has examples of this. */
4381 if (GET_CODE (entry_parm) == PARALLEL)
4382 emit_group_store (validize_mem (stack_parm), entry_parm,
4383 int_size_in_bytes (TREE_TYPE (parm)),
4384 TYPE_ALIGN (TREE_TYPE (parm)));
4387 move_block_from_reg (REGNO (entry_parm),
4388 validize_mem (stack_parm), nregs,
4389 int_size_in_bytes (TREE_TYPE (parm)));
4391 entry_parm = stack_parm;
4396 /* If we didn't decide this parm came in a register,
4397 by default it came on the stack. */
4398 if (entry_parm == 0)
4399 entry_parm = stack_parm;
4401 /* Record permanently how this parm was passed. */
4402 DECL_INCOMING_RTL (parm) = entry_parm;
4404 /* If there is actually space on the stack for this parm,
4405 count it in stack_args_size; otherwise set stack_parm to 0
4406 to indicate there is no preallocated stack slot for the parm. */
4408 if (entry_parm == stack_parm
4409 || (GET_CODE (entry_parm) == PARALLEL
4410 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4411 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4412 /* On some machines, even if a parm value arrives in a register
4413 there is still an (uninitialized) stack slot allocated for it.
4415 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4416 whether this parameter already has a stack slot allocated,
4417 because an arg block exists only if current_function_args_size
4418 is larger than some threshold, and we haven't calculated that
4419 yet. So, for now, we just assume that stack slots never exist
4421 || REG_PARM_STACK_SPACE (fndecl) > 0
4425 stack_args_size.constant += arg_size.constant;
4427 ADD_PARM_SIZE (stack_args_size, arg_size.var);
4430 /* No stack slot was pushed for this parm. */
4433 /* Update info on where next arg arrives in registers. */
4435 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4436 passed_type, named_arg);
4438 /* If we can't trust the parm stack slot to be aligned enough
4439 for its ultimate type, don't use that slot after entry.
4440 We'll make another stack slot, if we need one. */
4442 unsigned int thisparm_boundary
4443 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4445 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4449 /* If parm was passed in memory, and we need to convert it on entry,
4450 don't store it back in that same slot. */
4452 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4455 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4456 in the mode in which it arrives.
4457 STACK_PARM is an RTX for a stack slot where the parameter can live
4458 during the function (in case we want to put it there).
4459 STACK_PARM is 0 if no stack slot was pushed for it.
4461 Now output code if necessary to convert ENTRY_PARM to
4462 the type in which this function declares it,
4463 and store that result in an appropriate place,
4464 which may be a pseudo reg, may be STACK_PARM,
4465 or may be a local stack slot if STACK_PARM is 0.
4467 Set DECL_RTL to that place. */
4469 if (nominal_mode == BLKmode || GET_CODE (entry_parm) == PARALLEL)
4471 /* If a BLKmode arrives in registers, copy it to a stack slot.
4472 Handle calls that pass values in multiple non-contiguous
4473 locations. The Irix 6 ABI has examples of this. */
4474 if (GET_CODE (entry_parm) == REG
4475 || GET_CODE (entry_parm) == PARALLEL)
4478 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
4481 /* Note that we will be storing an integral number of words.
4482 So we have to be careful to ensure that we allocate an
4483 integral number of words. We do this below in the
4484 assign_stack_local if space was not allocated in the argument
4485 list. If it was, this will not work if PARM_BOUNDARY is not
4486 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4487 if it becomes a problem. */
4489 if (stack_parm == 0)
4492 = assign_stack_local (GET_MODE (entry_parm),
4494 set_mem_attributes (stack_parm, parm, 1);
4497 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4500 /* Handle calls that pass values in multiple non-contiguous
4501 locations. The Irix 6 ABI has examples of this. */
4502 if (GET_CODE (entry_parm) == PARALLEL)
4503 emit_group_store (validize_mem (stack_parm), entry_parm,
4504 int_size_in_bytes (TREE_TYPE (parm)),
4505 TYPE_ALIGN (TREE_TYPE (parm)));
4507 move_block_from_reg (REGNO (entry_parm),
4508 validize_mem (stack_parm),
4509 size_stored / UNITS_PER_WORD,
4510 int_size_in_bytes (TREE_TYPE (parm)));
4512 DECL_RTL (parm) = stack_parm;
4514 else if (! ((! optimize
4515 && ! DECL_REGISTER (parm)
4516 && ! DECL_INLINE (fndecl))
4517 /* layout_decl may set this. */
4518 || TREE_ADDRESSABLE (parm)
4519 || TREE_SIDE_EFFECTS (parm)
4520 /* If -ffloat-store specified, don't put explicit
4521 float variables into registers. */
4522 || (flag_float_store
4523 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4524 /* Always assign pseudo to structure return or item passed
4525 by invisible reference. */
4526 || passed_pointer || parm == function_result_decl)
4528 /* Store the parm in a pseudoregister during the function, but we
4529 may need to do it in a wider mode. */
4531 register rtx parmreg;
4532 unsigned int regno, regnoi = 0, regnor = 0;
4534 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4536 promoted_nominal_mode
4537 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4539 parmreg = gen_reg_rtx (promoted_nominal_mode);
4540 mark_user_reg (parmreg);
4542 /* If this was an item that we received a pointer to, set DECL_RTL
4547 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)), parmreg);
4548 set_mem_attributes (DECL_RTL (parm), parm, 1);
4551 DECL_RTL (parm) = parmreg;
4553 /* Copy the value into the register. */
4554 if (nominal_mode != passed_mode
4555 || promoted_nominal_mode != promoted_mode)
4558 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4559 mode, by the caller. We now have to convert it to
4560 NOMINAL_MODE, if different. However, PARMREG may be in
4561 a different mode than NOMINAL_MODE if it is being stored
4564 If ENTRY_PARM is a hard register, it might be in a register
4565 not valid for operating in its mode (e.g., an odd-numbered
4566 register for a DFmode). In that case, moves are the only
4567 thing valid, so we can't do a convert from there. This
4568 occurs when the calling sequence allow such misaligned
4571 In addition, the conversion may involve a call, which could
4572 clobber parameters which haven't been copied to pseudo
4573 registers yet. Therefore, we must first copy the parm to
4574 a pseudo reg here, and save the conversion until after all
4575 parameters have been moved. */
4577 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4579 emit_move_insn (tempreg, validize_mem (entry_parm));
4581 push_to_sequence (conversion_insns);
4582 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4584 /* TREE_USED gets set erroneously during expand_assignment. */
4585 save_tree_used = TREE_USED (parm);
4586 expand_assignment (parm,
4587 make_tree (nominal_type, tempreg), 0, 0);
4588 TREE_USED (parm) = save_tree_used;
4589 conversion_insns = get_insns ();
4594 emit_move_insn (parmreg, validize_mem (entry_parm));
4596 /* If we were passed a pointer but the actual value
4597 can safely live in a register, put it in one. */
4598 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4600 && ! DECL_REGISTER (parm)
4601 && ! DECL_INLINE (fndecl))
4602 /* layout_decl may set this. */
4603 || TREE_ADDRESSABLE (parm)
4604 || TREE_SIDE_EFFECTS (parm)
4605 /* If -ffloat-store specified, don't put explicit
4606 float variables into registers. */
4607 || (flag_float_store
4608 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE)))
4610 /* We can't use nominal_mode, because it will have been set to
4611 Pmode above. We must use the actual mode of the parm. */
4612 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4613 mark_user_reg (parmreg);
4614 emit_move_insn (parmreg, DECL_RTL (parm));
4615 DECL_RTL (parm) = parmreg;
4616 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4620 #ifdef FUNCTION_ARG_CALLEE_COPIES
4621 /* If we are passed an arg by reference and it is our responsibility
4622 to make a copy, do it now.
4623 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4624 original argument, so we must recreate them in the call to
4625 FUNCTION_ARG_CALLEE_COPIES. */
4626 /* ??? Later add code to handle the case that if the argument isn't
4627 modified, don't do the copy. */
4629 else if (passed_pointer
4630 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4631 TYPE_MODE (DECL_ARG_TYPE (parm)),
4632 DECL_ARG_TYPE (parm),
4634 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4637 tree type = DECL_ARG_TYPE (parm);
4639 /* This sequence may involve a library call perhaps clobbering
4640 registers that haven't been copied to pseudos yet. */
4642 push_to_sequence (conversion_insns);
4644 if (!COMPLETE_TYPE_P (type)
4645 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4646 /* This is a variable sized object. */
4647 copy = gen_rtx_MEM (BLKmode,
4648 allocate_dynamic_stack_space
4649 (expr_size (parm), NULL_RTX,
4650 TYPE_ALIGN (type)));
4652 copy = assign_stack_temp (TYPE_MODE (type),
4653 int_size_in_bytes (type), 1);
4654 set_mem_attributes (copy, parm, 1);
4656 store_expr (parm, copy, 0);
4657 emit_move_insn (parmreg, XEXP (copy, 0));
4658 if (current_function_check_memory_usage)
4659 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
4660 XEXP (copy, 0), Pmode,
4661 GEN_INT (int_size_in_bytes (type)),
4662 TYPE_MODE (sizetype),
4663 GEN_INT (MEMORY_USE_RW),
4664 TYPE_MODE (integer_type_node));
4665 conversion_insns = get_insns ();
4669 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4671 /* In any case, record the parm's desired stack location
4672 in case we later discover it must live in the stack.
4674 If it is a COMPLEX value, store the stack location for both
4677 if (GET_CODE (parmreg) == CONCAT)
4678 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4680 regno = REGNO (parmreg);
4682 if (regno >= max_parm_reg)
4685 int old_max_parm_reg = max_parm_reg;
4687 /* It's slow to expand this one register at a time,
4688 but it's also rare and we need max_parm_reg to be
4689 precisely correct. */
4690 max_parm_reg = regno + 1;
4691 new = (rtx *) xrealloc (parm_reg_stack_loc,
4692 max_parm_reg * sizeof (rtx));
4693 bzero ((char *) (new + old_max_parm_reg),
4694 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4695 parm_reg_stack_loc = new;
4698 if (GET_CODE (parmreg) == CONCAT)
4700 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
4702 regnor = REGNO (gen_realpart (submode, parmreg));
4703 regnoi = REGNO (gen_imagpart (submode, parmreg));
4705 if (stack_parm != 0)
4707 parm_reg_stack_loc[regnor]
4708 = gen_realpart (submode, stack_parm);
4709 parm_reg_stack_loc[regnoi]
4710 = gen_imagpart (submode, stack_parm);
4714 parm_reg_stack_loc[regnor] = 0;
4715 parm_reg_stack_loc[regnoi] = 0;
4719 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
4721 /* Mark the register as eliminable if we did no conversion
4722 and it was copied from memory at a fixed offset,
4723 and the arg pointer was not copied to a pseudo-reg.
4724 If the arg pointer is a pseudo reg or the offset formed
4725 an invalid address, such memory-equivalences
4726 as we make here would screw up life analysis for it. */
4727 if (nominal_mode == passed_mode
4730 && GET_CODE (stack_parm) == MEM
4731 && stack_offset.var == 0
4732 && reg_mentioned_p (virtual_incoming_args_rtx,
4733 XEXP (stack_parm, 0)))
4735 rtx linsn = get_last_insn ();
4738 /* Mark complex types separately. */
4739 if (GET_CODE (parmreg) == CONCAT)
4740 /* Scan backwards for the set of the real and
4742 for (sinsn = linsn; sinsn != 0;
4743 sinsn = prev_nonnote_insn (sinsn))
4745 set = single_set (sinsn);
4747 && SET_DEST (set) == regno_reg_rtx [regnoi])
4749 = gen_rtx_EXPR_LIST (REG_EQUIV,
4750 parm_reg_stack_loc[regnoi],
4753 && SET_DEST (set) == regno_reg_rtx [regnor])
4755 = gen_rtx_EXPR_LIST (REG_EQUIV,
4756 parm_reg_stack_loc[regnor],
4759 else if ((set = single_set (linsn)) != 0
4760 && SET_DEST (set) == parmreg)
4762 = gen_rtx_EXPR_LIST (REG_EQUIV,
4763 stack_parm, REG_NOTES (linsn));
4766 /* For pointer data type, suggest pointer register. */
4767 if (POINTER_TYPE_P (TREE_TYPE (parm)))
4768 mark_reg_pointer (parmreg,
4769 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
4774 /* Value must be stored in the stack slot STACK_PARM
4775 during function execution. */
4777 if (promoted_mode != nominal_mode)
4779 /* Conversion is required. */
4780 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4782 emit_move_insn (tempreg, validize_mem (entry_parm));
4784 push_to_sequence (conversion_insns);
4785 entry_parm = convert_to_mode (nominal_mode, tempreg,
4786 TREE_UNSIGNED (TREE_TYPE (parm)));
4789 /* ??? This may need a big-endian conversion on sparc64. */
4790 stack_parm = change_address (stack_parm, nominal_mode,
4793 conversion_insns = get_insns ();
4798 if (entry_parm != stack_parm)
4800 if (stack_parm == 0)
4803 = assign_stack_local (GET_MODE (entry_parm),
4804 GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
4805 set_mem_attributes (stack_parm, parm, 1);
4808 if (promoted_mode != nominal_mode)
4810 push_to_sequence (conversion_insns);
4811 emit_move_insn (validize_mem (stack_parm),
4812 validize_mem (entry_parm));
4813 conversion_insns = get_insns ();
4817 emit_move_insn (validize_mem (stack_parm),
4818 validize_mem (entry_parm));
4820 if (current_function_check_memory_usage)
4822 push_to_sequence (conversion_insns);
4823 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
4824 XEXP (stack_parm, 0), Pmode,
4825 GEN_INT (GET_MODE_SIZE (GET_MODE
4827 TYPE_MODE (sizetype),
4828 GEN_INT (MEMORY_USE_RW),
4829 TYPE_MODE (integer_type_node));
4831 conversion_insns = get_insns ();
4834 DECL_RTL (parm) = stack_parm;
4837 /* If this "parameter" was the place where we are receiving the
4838 function's incoming structure pointer, set up the result. */
4839 if (parm == function_result_decl)
4841 tree result = DECL_RESULT (fndecl);
4844 = gen_rtx_MEM (DECL_MODE (result), DECL_RTL (parm));
4846 set_mem_attributes (DECL_RTL (result), result, 1);
4850 /* Output all parameter conversion instructions (possibly including calls)
4851 now that all parameters have been copied out of hard registers. */
4852 emit_insns (conversion_insns);
4854 last_parm_insn = get_last_insn ();
4856 current_function_args_size = stack_args_size.constant;
4858 /* Adjust function incoming argument size for alignment and
4861 #ifdef REG_PARM_STACK_SPACE
4862 #ifndef MAYBE_REG_PARM_STACK_SPACE
4863 current_function_args_size = MAX (current_function_args_size,
4864 REG_PARM_STACK_SPACE (fndecl));
4868 #ifdef STACK_BOUNDARY
4869 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
4871 current_function_args_size
4872 = ((current_function_args_size + STACK_BYTES - 1)
4873 / STACK_BYTES) * STACK_BYTES;
4876 #ifdef ARGS_GROW_DOWNWARD
4877 current_function_arg_offset_rtx
4878 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
4879 : expand_expr (size_diffop (stack_args_size.var,
4880 size_int (-stack_args_size.constant)),
4881 NULL_RTX, VOIDmode, EXPAND_MEMORY_USE_BAD));
4883 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
4886 /* See how many bytes, if any, of its args a function should try to pop
4889 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
4890 current_function_args_size);
4892 /* For stdarg.h function, save info about
4893 regs and stack space used by the named args. */
4896 current_function_args_info = args_so_far;
4898 /* Set the rtx used for the function return value. Put this in its
4899 own variable so any optimizers that need this information don't have
4900 to include tree.h. Do this here so it gets done when an inlined
4901 function gets output. */
4903 current_function_return_rtx = DECL_RTL (DECL_RESULT (fndecl));
4906 /* Indicate whether REGNO is an incoming argument to the current function
4907 that was promoted to a wider mode. If so, return the RTX for the
4908 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
4909 that REGNO is promoted from and whether the promotion was signed or
4912 #ifdef PROMOTE_FUNCTION_ARGS
4915 promoted_input_arg (regno, pmode, punsignedp)
4917 enum machine_mode *pmode;
4922 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
4923 arg = TREE_CHAIN (arg))
4924 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
4925 && REGNO (DECL_INCOMING_RTL (arg)) == regno
4926 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
4928 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
4929 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
4931 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
4932 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
4933 && mode != DECL_MODE (arg))
4935 *pmode = DECL_MODE (arg);
4936 *punsignedp = unsignedp;
4937 return DECL_INCOMING_RTL (arg);
4946 /* Compute the size and offset from the start of the stacked arguments for a
4947 parm passed in mode PASSED_MODE and with type TYPE.
4949 INITIAL_OFFSET_PTR points to the current offset into the stacked
4952 The starting offset and size for this parm are returned in *OFFSET_PTR
4953 and *ARG_SIZE_PTR, respectively.
4955 IN_REGS is non-zero if the argument will be passed in registers. It will
4956 never be set if REG_PARM_STACK_SPACE is not defined.
4958 FNDECL is the function in which the argument was defined.
4960 There are two types of rounding that are done. The first, controlled by
4961 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
4962 list to be aligned to the specific boundary (in bits). This rounding
4963 affects the initial and starting offsets, but not the argument size.
4965 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
4966 optionally rounds the size of the parm to PARM_BOUNDARY. The
4967 initial offset is not affected by this rounding, while the size always
4968 is and the starting offset may be. */
4970 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
4971 initial_offset_ptr is positive because locate_and_pad_parm's
4972 callers pass in the total size of args so far as
4973 initial_offset_ptr. arg_size_ptr is always positive.*/
4976 locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
4977 initial_offset_ptr, offset_ptr, arg_size_ptr,
4979 enum machine_mode passed_mode;
4981 int in_regs ATTRIBUTE_UNUSED;
4982 tree fndecl ATTRIBUTE_UNUSED;
4983 struct args_size *initial_offset_ptr;
4984 struct args_size *offset_ptr;
4985 struct args_size *arg_size_ptr;
4986 struct args_size *alignment_pad;
4990 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
4991 enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
4992 int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
4994 #ifdef REG_PARM_STACK_SPACE
4995 /* If we have found a stack parm before we reach the end of the
4996 area reserved for registers, skip that area. */
4999 int reg_parm_stack_space = 0;
5001 #ifdef MAYBE_REG_PARM_STACK_SPACE
5002 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
5004 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5006 if (reg_parm_stack_space > 0)
5008 if (initial_offset_ptr->var)
5010 initial_offset_ptr->var
5011 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5012 ssize_int (reg_parm_stack_space));
5013 initial_offset_ptr->constant = 0;
5015 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5016 initial_offset_ptr->constant = reg_parm_stack_space;
5019 #endif /* REG_PARM_STACK_SPACE */
5021 arg_size_ptr->var = 0;
5022 arg_size_ptr->constant = 0;
5024 #ifdef ARGS_GROW_DOWNWARD
5025 if (initial_offset_ptr->var)
5027 offset_ptr->constant = 0;
5028 offset_ptr->var = size_binop (MINUS_EXPR, ssize_int (0),
5029 initial_offset_ptr->var);
5033 offset_ptr->constant = - initial_offset_ptr->constant;
5034 offset_ptr->var = 0;
5036 if (where_pad != none
5037 && (TREE_CODE (sizetree) != INTEGER_CST
5038 || ((TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)))
5039 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5040 SUB_PARM_SIZE (*offset_ptr, sizetree);
5041 if (where_pad != downward)
5042 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad);
5043 if (initial_offset_ptr->var)
5044 arg_size_ptr->var = size_binop (MINUS_EXPR,
5045 size_binop (MINUS_EXPR,
5047 initial_offset_ptr->var),
5051 arg_size_ptr->constant = (- initial_offset_ptr->constant
5052 - offset_ptr->constant);
5054 #else /* !ARGS_GROW_DOWNWARD */
5055 pad_to_arg_alignment (initial_offset_ptr, boundary, alignment_pad);
5056 *offset_ptr = *initial_offset_ptr;
5058 #ifdef PUSH_ROUNDING
5059 if (passed_mode != BLKmode)
5060 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5063 /* Pad_below needs the pre-rounded size to know how much to pad below
5064 so this must be done before rounding up. */
5065 if (where_pad == downward
5066 /* However, BLKmode args passed in regs have their padding done elsewhere.
5067 The stack slot must be able to hold the entire register. */
5068 && !(in_regs && passed_mode == BLKmode))
5069 pad_below (offset_ptr, passed_mode, sizetree);
5071 if (where_pad != none
5072 && (TREE_CODE (sizetree) != INTEGER_CST
5073 || ((TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)))
5074 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5076 ADD_PARM_SIZE (*arg_size_ptr, sizetree);
5077 #endif /* ARGS_GROW_DOWNWARD */
5080 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5081 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5084 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad)
5085 struct args_size *offset_ptr;
5087 struct args_size *alignment_pad;
5089 tree save_var = NULL_TREE;
5090 HOST_WIDE_INT save_constant = 0;
5092 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5094 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5096 save_var = offset_ptr->var;
5097 save_constant = offset_ptr->constant;
5100 alignment_pad->var = NULL_TREE;
5101 alignment_pad->constant = 0;
5103 if (boundary > BITS_PER_UNIT)
5105 if (offset_ptr->var)
5108 #ifdef ARGS_GROW_DOWNWARD
5113 (ARGS_SIZE_TREE (*offset_ptr),
5114 boundary / BITS_PER_UNIT);
5115 offset_ptr->constant = 0; /*?*/
5116 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5117 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5122 offset_ptr->constant =
5123 #ifdef ARGS_GROW_DOWNWARD
5124 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
5126 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
5128 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5129 alignment_pad->constant = offset_ptr->constant - save_constant;
5134 #ifndef ARGS_GROW_DOWNWARD
5136 pad_below (offset_ptr, passed_mode, sizetree)
5137 struct args_size *offset_ptr;
5138 enum machine_mode passed_mode;
5141 if (passed_mode != BLKmode)
5143 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5144 offset_ptr->constant
5145 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5146 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5147 - GET_MODE_SIZE (passed_mode));
5151 if (TREE_CODE (sizetree) != INTEGER_CST
5152 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5154 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5155 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5157 ADD_PARM_SIZE (*offset_ptr, s2);
5158 SUB_PARM_SIZE (*offset_ptr, sizetree);
5164 /* Walk the tree of blocks describing the binding levels within a function
5165 and warn about uninitialized variables.
5166 This is done after calling flow_analysis and before global_alloc
5167 clobbers the pseudo-regs to hard regs. */
5170 uninitialized_vars_warning (block)
5173 register tree decl, sub;
5174 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5176 if (warn_uninitialized
5177 && TREE_CODE (decl) == VAR_DECL
5178 /* These warnings are unreliable for and aggregates
5179 because assigning the fields one by one can fail to convince
5180 flow.c that the entire aggregate was initialized.
5181 Unions are troublesome because members may be shorter. */
5182 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5183 && DECL_RTL (decl) != 0
5184 && GET_CODE (DECL_RTL (decl)) == REG
5185 /* Global optimizations can make it difficult to determine if a
5186 particular variable has been initialized. However, a VAR_DECL
5187 with a nonzero DECL_INITIAL had an initializer, so do not
5188 claim it is potentially uninitialized.
5190 We do not care about the actual value in DECL_INITIAL, so we do
5191 not worry that it may be a dangling pointer. */
5192 && DECL_INITIAL (decl) == NULL_TREE
5193 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5194 warning_with_decl (decl,
5195 "`%s' might be used uninitialized in this function");
5197 && TREE_CODE (decl) == VAR_DECL
5198 && DECL_RTL (decl) != 0
5199 && GET_CODE (DECL_RTL (decl)) == REG
5200 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5201 warning_with_decl (decl,
5202 "variable `%s' might be clobbered by `longjmp' or `vfork'");
5204 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5205 uninitialized_vars_warning (sub);
5208 /* Do the appropriate part of uninitialized_vars_warning
5209 but for arguments instead of local variables. */
5212 setjmp_args_warning ()
5215 for (decl = DECL_ARGUMENTS (current_function_decl);
5216 decl; decl = TREE_CHAIN (decl))
5217 if (DECL_RTL (decl) != 0
5218 && GET_CODE (DECL_RTL (decl)) == REG
5219 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5220 warning_with_decl (decl, "argument `%s' might be clobbered by `longjmp' or `vfork'");
5223 /* If this function call setjmp, put all vars into the stack
5224 unless they were declared `register'. */
5227 setjmp_protect (block)
5230 register tree decl, sub;
5231 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5232 if ((TREE_CODE (decl) == VAR_DECL
5233 || TREE_CODE (decl) == PARM_DECL)
5234 && DECL_RTL (decl) != 0
5235 && (GET_CODE (DECL_RTL (decl)) == REG
5236 || (GET_CODE (DECL_RTL (decl)) == MEM
5237 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5238 /* If this variable came from an inline function, it must be
5239 that its life doesn't overlap the setjmp. If there was a
5240 setjmp in the function, it would already be in memory. We
5241 must exclude such variable because their DECL_RTL might be
5242 set to strange things such as virtual_stack_vars_rtx. */
5243 && ! DECL_FROM_INLINE (decl)
5245 #ifdef NON_SAVING_SETJMP
5246 /* If longjmp doesn't restore the registers,
5247 don't put anything in them. */
5251 ! DECL_REGISTER (decl)))
5252 put_var_into_stack (decl);
5253 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5254 setjmp_protect (sub);
5257 /* Like the previous function, but for args instead of local variables. */
5260 setjmp_protect_args ()
5263 for (decl = DECL_ARGUMENTS (current_function_decl);
5264 decl; decl = TREE_CHAIN (decl))
5265 if ((TREE_CODE (decl) == VAR_DECL
5266 || TREE_CODE (decl) == PARM_DECL)
5267 && DECL_RTL (decl) != 0
5268 && (GET_CODE (DECL_RTL (decl)) == REG
5269 || (GET_CODE (DECL_RTL (decl)) == MEM
5270 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5272 /* If longjmp doesn't restore the registers,
5273 don't put anything in them. */
5274 #ifdef NON_SAVING_SETJMP
5278 ! DECL_REGISTER (decl)))
5279 put_var_into_stack (decl);
5282 /* Return the context-pointer register corresponding to DECL,
5283 or 0 if it does not need one. */
5286 lookup_static_chain (decl)
5289 tree context = decl_function_context (decl);
5293 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5296 /* We treat inline_function_decl as an alias for the current function
5297 because that is the inline function whose vars, types, etc.
5298 are being merged into the current function.
5299 See expand_inline_function. */
5300 if (context == current_function_decl || context == inline_function_decl)
5301 return virtual_stack_vars_rtx;
5303 for (link = context_display; link; link = TREE_CHAIN (link))
5304 if (TREE_PURPOSE (link) == context)
5305 return RTL_EXPR_RTL (TREE_VALUE (link));
5310 /* Convert a stack slot address ADDR for variable VAR
5311 (from a containing function)
5312 into an address valid in this function (using a static chain). */
5315 fix_lexical_addr (addr, var)
5320 HOST_WIDE_INT displacement;
5321 tree context = decl_function_context (var);
5322 struct function *fp;
5325 /* If this is the present function, we need not do anything. */
5326 if (context == current_function_decl || context == inline_function_decl)
5329 for (fp = outer_function_chain; fp; fp = fp->next)
5330 if (fp->decl == context)
5336 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5337 addr = XEXP (XEXP (addr, 0), 0);
5339 /* Decode given address as base reg plus displacement. */
5340 if (GET_CODE (addr) == REG)
5341 basereg = addr, displacement = 0;
5342 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5343 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5347 /* We accept vars reached via the containing function's
5348 incoming arg pointer and via its stack variables pointer. */
5349 if (basereg == fp->internal_arg_pointer)
5351 /* If reached via arg pointer, get the arg pointer value
5352 out of that function's stack frame.
5354 There are two cases: If a separate ap is needed, allocate a
5355 slot in the outer function for it and dereference it that way.
5356 This is correct even if the real ap is actually a pseudo.
5357 Otherwise, just adjust the offset from the frame pointer to
5360 #ifdef NEED_SEPARATE_AP
5363 if (fp->x_arg_pointer_save_area == 0)
5364 fp->x_arg_pointer_save_area
5365 = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, fp);
5367 addr = fix_lexical_addr (XEXP (fp->x_arg_pointer_save_area, 0), var);
5368 addr = memory_address (Pmode, addr);
5370 base = gen_rtx_MEM (Pmode, addr);
5371 MEM_ALIAS_SET (base) = get_frame_alias_set ();
5372 base = copy_to_reg (base);
5374 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5375 base = lookup_static_chain (var);
5379 else if (basereg == virtual_stack_vars_rtx)
5381 /* This is the same code as lookup_static_chain, duplicated here to
5382 avoid an extra call to decl_function_context. */
5385 for (link = context_display; link; link = TREE_CHAIN (link))
5386 if (TREE_PURPOSE (link) == context)
5388 base = RTL_EXPR_RTL (TREE_VALUE (link));
5396 /* Use same offset, relative to appropriate static chain or argument
5398 return plus_constant (base, displacement);
5401 /* Return the address of the trampoline for entering nested fn FUNCTION.
5402 If necessary, allocate a trampoline (in the stack frame)
5403 and emit rtl to initialize its contents (at entry to this function). */
5406 trampoline_address (function)
5412 struct function *fp;
5415 /* Find an existing trampoline and return it. */
5416 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5417 if (TREE_PURPOSE (link) == function)
5419 round_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5421 for (fp = outer_function_chain; fp; fp = fp->next)
5422 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5423 if (TREE_PURPOSE (link) == function)
5425 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5427 return round_trampoline_addr (tramp);
5430 /* None exists; we must make one. */
5432 /* Find the `struct function' for the function containing FUNCTION. */
5434 fn_context = decl_function_context (function);
5435 if (fn_context != current_function_decl
5436 && fn_context != inline_function_decl)
5437 for (fp = outer_function_chain; fp; fp = fp->next)
5438 if (fp->decl == fn_context)
5441 /* Allocate run-time space for this trampoline
5442 (usually in the defining function's stack frame). */
5443 #ifdef ALLOCATE_TRAMPOLINE
5444 tramp = ALLOCATE_TRAMPOLINE (fp);
5446 /* If rounding needed, allocate extra space
5447 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5448 #ifdef TRAMPOLINE_ALIGNMENT
5449 #define TRAMPOLINE_REAL_SIZE \
5450 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5452 #define TRAMPOLINE_REAL_SIZE (TRAMPOLINE_SIZE)
5454 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5458 /* Record the trampoline for reuse and note it for later initialization
5459 by expand_function_end. */
5462 push_obstacks (fp->function_maybepermanent_obstack,
5463 fp->function_maybepermanent_obstack);
5464 rtlexp = make_node (RTL_EXPR);
5465 RTL_EXPR_RTL (rtlexp) = tramp;
5466 fp->x_trampoline_list = tree_cons (function, rtlexp,
5467 fp->x_trampoline_list);
5472 /* Make the RTL_EXPR node temporary, not momentary, so that the
5473 trampoline_list doesn't become garbage. */
5474 int momentary = suspend_momentary ();
5475 rtlexp = make_node (RTL_EXPR);
5476 resume_momentary (momentary);
5478 RTL_EXPR_RTL (rtlexp) = tramp;
5479 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5482 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5483 return round_trampoline_addr (tramp);
5486 /* Given a trampoline address,
5487 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5490 round_trampoline_addr (tramp)
5493 #ifdef TRAMPOLINE_ALIGNMENT
5494 /* Round address up to desired boundary. */
5495 rtx temp = gen_reg_rtx (Pmode);
5496 temp = expand_binop (Pmode, add_optab, tramp,
5497 GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1),
5498 temp, 0, OPTAB_LIB_WIDEN);
5499 tramp = expand_binop (Pmode, and_optab, temp,
5500 GEN_INT (- TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT),
5501 temp, 0, OPTAB_LIB_WIDEN);
5506 /* Put all this function's BLOCK nodes including those that are chained
5507 onto the first block into a vector, and return it.
5508 Also store in each NOTE for the beginning or end of a block
5509 the index of that block in the vector.
5510 The arguments are BLOCK, the chain of top-level blocks of the function,
5511 and INSNS, the insn chain of the function. */
5517 tree *block_vector, *last_block_vector;
5519 tree block = DECL_INITIAL (current_function_decl);
5524 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5525 depth-first order. */
5526 block_vector = get_block_vector (block, &n_blocks);
5527 block_stack = (tree *) xmalloc (n_blocks * sizeof (tree));
5529 last_block_vector = identify_blocks_1 (get_insns (),
5531 block_vector + n_blocks,
5534 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5535 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5536 if (0 && last_block_vector != block_vector + n_blocks)
5539 free (block_vector);
5543 /* Subroutine of identify_blocks. Do the block substitution on the
5544 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
5546 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5547 BLOCK_VECTOR is incremented for each block seen. */
5550 identify_blocks_1 (insns, block_vector, end_block_vector, orig_block_stack)
5553 tree *end_block_vector;
5554 tree *orig_block_stack;
5557 tree *block_stack = orig_block_stack;
5559 for (insn = insns; insn; insn = NEXT_INSN (insn))
5561 if (GET_CODE (insn) == NOTE)
5563 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5567 /* If there are more block notes than BLOCKs, something
5569 if (block_vector == end_block_vector)
5572 b = *block_vector++;
5573 NOTE_BLOCK (insn) = b;
5576 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5578 /* If there are more NOTE_INSN_BLOCK_ENDs than
5579 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
5580 if (block_stack == orig_block_stack)
5583 NOTE_BLOCK (insn) = *--block_stack;
5586 else if (GET_CODE (insn) == CALL_INSN
5587 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5589 rtx cp = PATTERN (insn);
5591 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
5592 end_block_vector, block_stack);
5594 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
5595 end_block_vector, block_stack);
5597 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
5598 end_block_vector, block_stack);
5602 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
5603 something is badly wrong. */
5604 if (block_stack != orig_block_stack)
5607 return block_vector;
5610 /* Identify BLOCKs referenced by more than one
5611 NOTE_INSN_BLOCK_{BEG,END}, and create duplicate blocks. */
5616 tree block = DECL_INITIAL (current_function_decl);
5617 varray_type block_stack;
5619 if (block == NULL_TREE)
5622 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
5624 /* Prune the old trees away, so that they don't get in the way. */
5625 BLOCK_SUBBLOCKS (block) = NULL_TREE;
5626 BLOCK_CHAIN (block) = NULL_TREE;
5628 reorder_blocks_1 (get_insns (), block, &block_stack);
5630 BLOCK_SUBBLOCKS (block)
5631 = blocks_nreverse (BLOCK_SUBBLOCKS (block));
5633 VARRAY_FREE (block_stack);
5636 /* Helper function for reorder_blocks. Process the insn chain beginning
5637 at INSNS. Recurse for CALL_PLACEHOLDER insns. */
5640 reorder_blocks_1 (insns, current_block, p_block_stack)
5643 varray_type *p_block_stack;
5647 for (insn = insns; insn; insn = NEXT_INSN (insn))
5649 if (GET_CODE (insn) == NOTE)
5651 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5653 tree block = NOTE_BLOCK (insn);
5654 /* If we have seen this block before, copy it. */
5655 if (TREE_ASM_WRITTEN (block))
5657 block = copy_node (block);
5658 NOTE_BLOCK (insn) = block;
5660 BLOCK_SUBBLOCKS (block) = 0;
5661 TREE_ASM_WRITTEN (block) = 1;
5662 BLOCK_SUPERCONTEXT (block) = current_block;
5663 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
5664 BLOCK_SUBBLOCKS (current_block) = block;
5665 current_block = block;
5666 VARRAY_PUSH_TREE (*p_block_stack, block);
5668 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5670 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
5671 VARRAY_POP (*p_block_stack);
5672 BLOCK_SUBBLOCKS (current_block)
5673 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5674 current_block = BLOCK_SUPERCONTEXT (current_block);
5677 else if (GET_CODE (insn) == CALL_INSN
5678 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5680 rtx cp = PATTERN (insn);
5681 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
5683 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
5685 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
5690 /* Reverse the order of elements in the chain T of blocks,
5691 and return the new head of the chain (old last element). */
5697 register tree prev = 0, decl, next;
5698 for (decl = t; decl; decl = next)
5700 next = BLOCK_CHAIN (decl);
5701 BLOCK_CHAIN (decl) = prev;
5707 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
5708 non-NULL, list them all into VECTOR, in a depth-first preorder
5709 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
5713 all_blocks (block, vector)
5721 TREE_ASM_WRITTEN (block) = 0;
5723 /* Record this block. */
5725 vector[n_blocks] = block;
5729 /* Record the subblocks, and their subblocks... */
5730 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
5731 vector ? vector + n_blocks : 0);
5732 block = BLOCK_CHAIN (block);
5738 /* Return a vector containing all the blocks rooted at BLOCK. The
5739 number of elements in the vector is stored in N_BLOCKS_P. The
5740 vector is dynamically allocated; it is the caller's responsibility
5741 to call `free' on the pointer returned. */
5744 get_block_vector (block, n_blocks_p)
5750 *n_blocks_p = all_blocks (block, NULL);
5751 block_vector = (tree *) xmalloc (*n_blocks_p * sizeof (tree));
5752 all_blocks (block, block_vector);
5754 return block_vector;
5757 static int next_block_index = 2;
5759 /* Set BLOCK_NUMBER for all the blocks in FN. */
5769 /* For SDB and XCOFF debugging output, we start numbering the blocks
5770 from 1 within each function, rather than keeping a running
5772 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
5773 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
5774 next_block_index = 1;
5777 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
5779 /* The top-level BLOCK isn't numbered at all. */
5780 for (i = 1; i < n_blocks; ++i)
5781 /* We number the blocks from two. */
5782 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
5784 free (block_vector);
5790 /* Allocate a function structure and reset its contents to the defaults. */
5792 prepare_function_start ()
5794 cfun = (struct function *) xcalloc (1, sizeof (struct function));
5796 init_stmt_for_function ();
5797 init_eh_for_function ();
5799 cse_not_expected = ! optimize;
5801 /* Caller save not needed yet. */
5802 caller_save_needed = 0;
5804 /* No stack slots have been made yet. */
5805 stack_slot_list = 0;
5807 current_function_has_nonlocal_label = 0;
5808 current_function_has_nonlocal_goto = 0;
5810 /* There is no stack slot for handling nonlocal gotos. */
5811 nonlocal_goto_handler_slots = 0;
5812 nonlocal_goto_stack_level = 0;
5814 /* No labels have been declared for nonlocal use. */
5815 nonlocal_labels = 0;
5816 nonlocal_goto_handler_labels = 0;
5818 /* No function calls so far in this function. */
5819 function_call_count = 0;
5821 /* No parm regs have been allocated.
5822 (This is important for output_inline_function.) */
5823 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
5825 /* Initialize the RTL mechanism. */
5828 /* Initialize the queue of pending postincrement and postdecrements,
5829 and some other info in expr.c. */
5832 /* We haven't done register allocation yet. */
5835 init_varasm_status (cfun);
5837 /* Clear out data used for inlining. */
5838 cfun->inlinable = 0;
5839 cfun->original_decl_initial = 0;
5840 cfun->original_arg_vector = 0;
5842 #ifdef STACK_BOUNDARY
5843 cfun->stack_alignment_needed = STACK_BOUNDARY;
5844 cfun->preferred_stack_boundary = STACK_BOUNDARY;
5846 cfun->stack_alignment_needed = 0;
5847 cfun->preferred_stack_boundary = 0;
5850 /* Set if a call to setjmp is seen. */
5851 current_function_calls_setjmp = 0;
5853 /* Set if a call to longjmp is seen. */
5854 current_function_calls_longjmp = 0;
5856 current_function_calls_alloca = 0;
5857 current_function_contains_functions = 0;
5858 current_function_is_leaf = 0;
5859 current_function_nothrow = 0;
5860 current_function_sp_is_unchanging = 0;
5861 current_function_uses_only_leaf_regs = 0;
5862 current_function_has_computed_jump = 0;
5863 current_function_is_thunk = 0;
5865 current_function_returns_pcc_struct = 0;
5866 current_function_returns_struct = 0;
5867 current_function_epilogue_delay_list = 0;
5868 current_function_uses_const_pool = 0;
5869 current_function_uses_pic_offset_table = 0;
5870 current_function_cannot_inline = 0;
5872 /* We have not yet needed to make a label to jump to for tail-recursion. */
5873 tail_recursion_label = 0;
5875 /* We haven't had a need to make a save area for ap yet. */
5876 arg_pointer_save_area = 0;
5878 /* No stack slots allocated yet. */
5881 /* No SAVE_EXPRs in this function yet. */
5884 /* No RTL_EXPRs in this function yet. */
5887 /* Set up to allocate temporaries. */
5890 /* Indicate that we need to distinguish between the return value of the
5891 present function and the return value of a function being called. */
5892 rtx_equal_function_value_matters = 1;
5894 /* Indicate that we have not instantiated virtual registers yet. */
5895 virtuals_instantiated = 0;
5897 /* Indicate we have no need of a frame pointer yet. */
5898 frame_pointer_needed = 0;
5900 /* By default assume not varargs or stdarg. */
5901 current_function_varargs = 0;
5902 current_function_stdarg = 0;
5904 /* We haven't made any trampolines for this function yet. */
5905 trampoline_list = 0;
5907 init_pending_stack_adjust ();
5908 inhibit_defer_pop = 0;
5910 current_function_outgoing_args_size = 0;
5912 if (init_lang_status)
5913 (*init_lang_status) (cfun);
5914 if (init_machine_status)
5915 (*init_machine_status) (cfun);
5918 /* Initialize the rtl expansion mechanism so that we can do simple things
5919 like generate sequences. This is used to provide a context during global
5920 initialization of some passes. */
5922 init_dummy_function_start ()
5924 prepare_function_start ();
5927 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
5928 and initialize static variables for generating RTL for the statements
5932 init_function_start (subr, filename, line)
5934 const char *filename;
5937 prepare_function_start ();
5939 /* Remember this function for later. */
5940 cfun->next_global = all_functions;
5941 all_functions = cfun;
5943 current_function_name = (*decl_printable_name) (subr, 2);
5946 /* Nonzero if this is a nested function that uses a static chain. */
5948 current_function_needs_context
5949 = (decl_function_context (current_function_decl) != 0
5950 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
5952 /* Within function body, compute a type's size as soon it is laid out. */
5953 immediate_size_expand++;
5955 /* Prevent ever trying to delete the first instruction of a function.
5956 Also tell final how to output a linenum before the function prologue.
5957 Note linenums could be missing, e.g. when compiling a Java .class file. */
5959 emit_line_note (filename, line);
5961 /* Make sure first insn is a note even if we don't want linenums.
5962 This makes sure the first insn will never be deleted.
5963 Also, final expects a note to appear there. */
5964 emit_note (NULL_PTR, NOTE_INSN_DELETED);
5966 /* Set flags used by final.c. */
5967 if (aggregate_value_p (DECL_RESULT (subr)))
5969 #ifdef PCC_STATIC_STRUCT_RETURN
5970 current_function_returns_pcc_struct = 1;
5972 current_function_returns_struct = 1;
5975 /* Warn if this value is an aggregate type,
5976 regardless of which calling convention we are using for it. */
5977 if (warn_aggregate_return
5978 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
5979 warning ("function returns an aggregate");
5981 current_function_returns_pointer
5982 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
5985 /* Make sure all values used by the optimization passes have sane
5988 init_function_for_compilation ()
5992 /* No prologue/epilogue insns yet. */
5993 VARRAY_GROW (prologue, 0);
5994 VARRAY_GROW (epilogue, 0);
5995 VARRAY_GROW (sibcall_epilogue, 0);
5998 /* Indicate that the current function uses extra args
5999 not explicitly mentioned in the argument list in any fashion. */
6004 current_function_varargs = 1;
6007 /* Expand a call to __main at the beginning of a possible main function. */
6009 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6010 #undef HAS_INIT_SECTION
6011 #define HAS_INIT_SECTION
6015 expand_main_function ()
6017 #if !defined (HAS_INIT_SECTION)
6018 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, NAME__MAIN), 0,
6020 #endif /* not HAS_INIT_SECTION */
6023 extern struct obstack permanent_obstack;
6025 /* Start the RTL for a new function, and set variables used for
6027 SUBR is the FUNCTION_DECL node.
6028 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6029 the function's parameters, which must be run at any return statement. */
6032 expand_function_start (subr, parms_have_cleanups)
6034 int parms_have_cleanups;
6037 rtx last_ptr = NULL_RTX;
6039 /* Make sure volatile mem refs aren't considered
6040 valid operands of arithmetic insns. */
6041 init_recog_no_volatile ();
6043 /* Set this before generating any memory accesses. */
6044 current_function_check_memory_usage
6045 = (flag_check_memory_usage
6046 && ! DECL_NO_CHECK_MEMORY_USAGE (current_function_decl));
6048 current_function_instrument_entry_exit
6049 = (flag_instrument_function_entry_exit
6050 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6052 current_function_limit_stack
6053 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6055 /* If function gets a static chain arg, store it in the stack frame.
6056 Do this first, so it gets the first stack slot offset. */
6057 if (current_function_needs_context)
6059 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
6061 /* Delay copying static chain if it is not a register to avoid
6062 conflicts with regs used for parameters. */
6063 if (! SMALL_REGISTER_CLASSES
6064 || GET_CODE (static_chain_incoming_rtx) == REG)
6065 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6068 /* If the parameters of this function need cleaning up, get a label
6069 for the beginning of the code which executes those cleanups. This must
6070 be done before doing anything with return_label. */
6071 if (parms_have_cleanups)
6072 cleanup_label = gen_label_rtx ();
6076 /* Make the label for return statements to jump to, if this machine
6077 does not have a one-instruction return and uses an epilogue,
6078 or if it returns a structure, or if it has parm cleanups. */
6080 if (cleanup_label == 0 && HAVE_return
6081 && ! current_function_instrument_entry_exit
6082 && ! current_function_returns_pcc_struct
6083 && ! (current_function_returns_struct && ! optimize))
6086 return_label = gen_label_rtx ();
6088 return_label = gen_label_rtx ();
6091 /* Initialize rtx used to return the value. */
6092 /* Do this before assign_parms so that we copy the struct value address
6093 before any library calls that assign parms might generate. */
6095 /* Decide whether to return the value in memory or in a register. */
6096 if (aggregate_value_p (DECL_RESULT (subr)))
6098 /* Returning something that won't go in a register. */
6099 register rtx value_address = 0;
6101 #ifdef PCC_STATIC_STRUCT_RETURN
6102 if (current_function_returns_pcc_struct)
6104 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6105 value_address = assemble_static_space (size);
6110 /* Expect to be passed the address of a place to store the value.
6111 If it is passed as an argument, assign_parms will take care of
6113 if (struct_value_incoming_rtx)
6115 value_address = gen_reg_rtx (Pmode);
6116 emit_move_insn (value_address, struct_value_incoming_rtx);
6121 DECL_RTL (DECL_RESULT (subr))
6122 = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
6123 set_mem_attributes (DECL_RTL (DECL_RESULT (subr)),
6124 DECL_RESULT (subr), 1);
6127 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6128 /* If return mode is void, this decl rtl should not be used. */
6129 DECL_RTL (DECL_RESULT (subr)) = 0;
6130 else if (parms_have_cleanups || current_function_instrument_entry_exit)
6132 /* If function will end with cleanup code for parms,
6133 compute the return values into a pseudo reg,
6134 which we will copy into the true return register
6135 after the cleanups are done. */
6137 enum machine_mode mode = DECL_MODE (DECL_RESULT (subr));
6139 #ifdef PROMOTE_FUNCTION_RETURN
6140 tree type = TREE_TYPE (DECL_RESULT (subr));
6141 int unsignedp = TREE_UNSIGNED (type);
6143 mode = promote_mode (type, mode, &unsignedp, 1);
6146 DECL_RTL (DECL_RESULT (subr)) = gen_reg_rtx (mode);
6149 /* Scalar, returned in a register. */
6151 DECL_RTL (DECL_RESULT (subr))
6152 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)), subr, 1);
6154 /* Mark this reg as the function's return value. */
6155 if (GET_CODE (DECL_RTL (DECL_RESULT (subr))) == REG)
6157 REG_FUNCTION_VALUE_P (DECL_RTL (DECL_RESULT (subr))) = 1;
6158 /* Needed because we may need to move this to memory
6159 in case it's a named return value whose address is taken. */
6160 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6164 /* Initialize rtx for parameters and local variables.
6165 In some cases this requires emitting insns. */
6167 assign_parms (subr);
6169 /* Copy the static chain now if it wasn't a register. The delay is to
6170 avoid conflicts with the parameter passing registers. */
6172 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6173 if (GET_CODE (static_chain_incoming_rtx) != REG)
6174 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6176 /* The following was moved from init_function_start.
6177 The move is supposed to make sdb output more accurate. */
6178 /* Indicate the beginning of the function body,
6179 as opposed to parm setup. */
6180 emit_note (NULL_PTR, NOTE_INSN_FUNCTION_BEG);
6182 if (GET_CODE (get_last_insn ()) != NOTE)
6183 emit_note (NULL_PTR, NOTE_INSN_DELETED);
6184 parm_birth_insn = get_last_insn ();
6186 context_display = 0;
6187 if (current_function_needs_context)
6189 /* Fetch static chain values for containing functions. */
6190 tem = decl_function_context (current_function_decl);
6191 /* Copy the static chain pointer into a pseudo. If we have
6192 small register classes, copy the value from memory if
6193 static_chain_incoming_rtx is a REG. */
6196 /* If the static chain originally came in a register, put it back
6197 there, then move it out in the next insn. The reason for
6198 this peculiar code is to satisfy function integration. */
6199 if (SMALL_REGISTER_CLASSES
6200 && GET_CODE (static_chain_incoming_rtx) == REG)
6201 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6202 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6207 tree rtlexp = make_node (RTL_EXPR);
6209 RTL_EXPR_RTL (rtlexp) = last_ptr;
6210 context_display = tree_cons (tem, rtlexp, context_display);
6211 tem = decl_function_context (tem);
6214 /* Chain thru stack frames, assuming pointer to next lexical frame
6215 is found at the place we always store it. */
6216 #ifdef FRAME_GROWS_DOWNWARD
6217 last_ptr = plus_constant (last_ptr, - GET_MODE_SIZE (Pmode));
6219 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr));
6220 MEM_ALIAS_SET (last_ptr) = get_frame_alias_set ();
6221 last_ptr = copy_to_reg (last_ptr);
6223 /* If we are not optimizing, ensure that we know that this
6224 piece of context is live over the entire function. */
6226 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6231 if (current_function_instrument_entry_exit)
6233 rtx fun = DECL_RTL (current_function_decl);
6234 if (GET_CODE (fun) == MEM)
6235 fun = XEXP (fun, 0);
6238 emit_library_call (profile_function_entry_libfunc, 0, VOIDmode, 2,
6240 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6242 hard_frame_pointer_rtx),
6246 /* After the display initializations is where the tail-recursion label
6247 should go, if we end up needing one. Ensure we have a NOTE here
6248 since some things (like trampolines) get placed before this. */
6249 tail_recursion_reentry = emit_note (NULL_PTR, NOTE_INSN_DELETED);
6251 /* Evaluate now the sizes of any types declared among the arguments. */
6252 for (tem = nreverse (get_pending_sizes ()); tem; tem = TREE_CHAIN (tem))
6254 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode,
6255 EXPAND_MEMORY_USE_BAD);
6256 /* Flush the queue in case this parameter declaration has
6261 /* Make sure there is a line number after the function entry setup code. */
6262 force_next_line_note ();
6265 /* Undo the effects of init_dummy_function_start. */
6267 expand_dummy_function_end ()
6269 /* End any sequences that failed to be closed due to syntax errors. */
6270 while (in_sequence_p ())
6273 /* Outside function body, can't compute type's actual size
6274 until next function's body starts. */
6276 free_after_parsing (cfun);
6277 free_after_compilation (cfun);
6282 /* Call DOIT for each hard register used as a return value from
6283 the current function. */
6286 diddle_return_value (doit, arg)
6287 void (*doit) PARAMS ((rtx, void *));
6290 rtx outgoing = current_function_return_rtx;
6296 pcc = (current_function_returns_struct
6297 || current_function_returns_pcc_struct);
6299 if ((GET_CODE (outgoing) == REG
6300 && REGNO (outgoing) >= FIRST_PSEUDO_REGISTER)
6303 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
6305 /* A PCC-style return returns a pointer to the memory in which
6306 the structure is stored. */
6308 type = build_pointer_type (type);
6310 #ifdef FUNCTION_OUTGOING_VALUE
6311 outgoing = FUNCTION_OUTGOING_VALUE (type, current_function_decl);
6313 outgoing = FUNCTION_VALUE (type, current_function_decl);
6315 /* If this is a BLKmode structure being returned in registers, then use
6316 the mode computed in expand_return. */
6317 if (GET_MODE (outgoing) == BLKmode)
6319 GET_MODE (DECL_RTL (DECL_RESULT (current_function_decl))));
6320 REG_FUNCTION_VALUE_P (outgoing) = 1;
6323 if (GET_CODE (outgoing) == REG)
6324 (*doit) (outgoing, arg);
6325 else if (GET_CODE (outgoing) == PARALLEL)
6329 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6331 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6333 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6340 do_clobber_return_reg (reg, arg)
6342 void *arg ATTRIBUTE_UNUSED;
6344 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6348 clobber_return_register ()
6350 diddle_return_value (do_clobber_return_reg, NULL);
6354 do_use_return_reg (reg, arg)
6356 void *arg ATTRIBUTE_UNUSED;
6358 emit_insn (gen_rtx_USE (VOIDmode, reg));
6362 use_return_register ()
6364 diddle_return_value (do_use_return_reg, NULL);
6367 /* Generate RTL for the end of the current function.
6368 FILENAME and LINE are the current position in the source file.
6370 It is up to language-specific callers to do cleanups for parameters--
6371 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
6374 expand_function_end (filename, line, end_bindings)
6375 const char *filename;
6381 #ifdef TRAMPOLINE_TEMPLATE
6382 static rtx initial_trampoline;
6385 finish_expr_for_function ();
6387 #ifdef NON_SAVING_SETJMP
6388 /* Don't put any variables in registers if we call setjmp
6389 on a machine that fails to restore the registers. */
6390 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6392 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6393 setjmp_protect (DECL_INITIAL (current_function_decl));
6395 setjmp_protect_args ();
6399 /* Save the argument pointer if a save area was made for it. */
6400 if (arg_pointer_save_area)
6402 /* arg_pointer_save_area may not be a valid memory address, so we
6403 have to check it and fix it if necessary. */
6406 emit_move_insn (validize_mem (arg_pointer_save_area),
6407 virtual_incoming_args_rtx);
6408 seq = gen_sequence ();
6410 emit_insn_before (seq, tail_recursion_reentry);
6413 /* Initialize any trampolines required by this function. */
6414 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6416 tree function = TREE_PURPOSE (link);
6417 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6418 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6419 #ifdef TRAMPOLINE_TEMPLATE
6424 #ifdef TRAMPOLINE_TEMPLATE
6425 /* First make sure this compilation has a template for
6426 initializing trampolines. */
6427 if (initial_trampoline == 0)
6429 end_temporary_allocation ();
6431 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6432 resume_temporary_allocation ();
6434 ggc_add_rtx_root (&initial_trampoline, 1);
6438 /* Generate insns to initialize the trampoline. */
6440 tramp = round_trampoline_addr (XEXP (tramp, 0));
6441 #ifdef TRAMPOLINE_TEMPLATE
6442 blktramp = change_address (initial_trampoline, BLKmode, tramp);
6443 emit_block_move (blktramp, initial_trampoline,
6444 GEN_INT (TRAMPOLINE_SIZE),
6445 TRAMPOLINE_ALIGNMENT);
6447 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6451 /* Put those insns at entry to the containing function (this one). */
6452 emit_insns_before (seq, tail_recursion_reentry);
6455 /* If we are doing stack checking and this function makes calls,
6456 do a stack probe at the start of the function to ensure we have enough
6457 space for another stack frame. */
6458 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6462 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6463 if (GET_CODE (insn) == CALL_INSN)
6466 probe_stack_range (STACK_CHECK_PROTECT,
6467 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6470 emit_insns_before (seq, tail_recursion_reentry);
6475 /* Warn about unused parms if extra warnings were specified. */
6476 /* Either ``-W -Wunused'' or ``-Wunused-parameter'' enables this
6477 warning. WARN_UNUSED_PARAMETER is negative when set by
6479 if (warn_unused_parameter > 0
6480 || (warn_unused_parameter < 0 && extra_warnings))
6484 for (decl = DECL_ARGUMENTS (current_function_decl);
6485 decl; decl = TREE_CHAIN (decl))
6486 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6487 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6488 warning_with_decl (decl, "unused parameter `%s'");
6491 /* Delete handlers for nonlocal gotos if nothing uses them. */
6492 if (nonlocal_goto_handler_slots != 0
6493 && ! current_function_has_nonlocal_label)
6496 /* End any sequences that failed to be closed due to syntax errors. */
6497 while (in_sequence_p ())
6500 /* Outside function body, can't compute type's actual size
6501 until next function's body starts. */
6502 immediate_size_expand--;
6504 clear_pending_stack_adjust ();
6505 do_pending_stack_adjust ();
6507 /* Mark the end of the function body.
6508 If control reaches this insn, the function can drop through
6509 without returning a value. */
6510 emit_note (NULL_PTR, NOTE_INSN_FUNCTION_END);
6512 /* Must mark the last line number note in the function, so that the test
6513 coverage code can avoid counting the last line twice. This just tells
6514 the code to ignore the immediately following line note, since there
6515 already exists a copy of this note somewhere above. This line number
6516 note is still needed for debugging though, so we can't delete it. */
6517 if (flag_test_coverage)
6518 emit_note (NULL_PTR, NOTE_INSN_REPEATED_LINE_NUMBER);
6520 /* Output a linenumber for the end of the function.
6521 SDB depends on this. */
6522 emit_line_note_force (filename, line);
6524 /* Output the label for the actual return from the function,
6525 if one is expected. This happens either because a function epilogue
6526 is used instead of a return instruction, or because a return was done
6527 with a goto in order to run local cleanups, or because of pcc-style
6528 structure returning. */
6532 /* Before the return label, clobber the return registers so that
6533 they are not propogated live to the rest of the function. This
6534 can only happen with functions that drop through; if there had
6535 been a return statement, there would have either been a return
6536 rtx, or a jump to the return label. */
6537 clobber_return_register ();
6539 emit_label (return_label);
6542 /* C++ uses this. */
6544 expand_end_bindings (0, 0, 0);
6546 /* Now handle any leftover exception regions that may have been
6547 created for the parameters. */
6549 rtx last = get_last_insn ();
6552 expand_leftover_cleanups ();
6554 /* If there are any catch_clauses remaining, output them now. */
6555 emit_insns (catch_clauses);
6556 catch_clauses = catch_clauses_last = NULL_RTX;
6557 /* If the above emitted any code, may sure we jump around it. */
6558 if (last != get_last_insn ())
6560 label = gen_label_rtx ();
6561 last = emit_jump_insn_after (gen_jump (label), last);
6562 last = emit_barrier_after (last);
6567 if (current_function_instrument_entry_exit)
6569 rtx fun = DECL_RTL (current_function_decl);
6570 if (GET_CODE (fun) == MEM)
6571 fun = XEXP (fun, 0);
6574 emit_library_call (profile_function_exit_libfunc, 0, VOIDmode, 2,
6576 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6578 hard_frame_pointer_rtx),
6582 /* If we had calls to alloca, and this machine needs
6583 an accurate stack pointer to exit the function,
6584 insert some code to save and restore the stack pointer. */
6585 #ifdef EXIT_IGNORE_STACK
6586 if (! EXIT_IGNORE_STACK)
6588 if (current_function_calls_alloca)
6592 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
6593 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
6596 /* If scalar return value was computed in a pseudo-reg,
6597 copy that to the hard return register. */
6598 if (DECL_RTL (DECL_RESULT (current_function_decl)) != 0
6599 && GET_CODE (DECL_RTL (DECL_RESULT (current_function_decl))) == REG
6600 && (REGNO (DECL_RTL (DECL_RESULT (current_function_decl)))
6601 >= FIRST_PSEUDO_REGISTER))
6603 rtx real_decl_result;
6605 #ifdef FUNCTION_OUTGOING_VALUE
6607 = FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl)),
6608 current_function_decl);
6611 = FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl)),
6612 current_function_decl);
6614 REG_FUNCTION_VALUE_P (real_decl_result) = 1;
6615 /* If this is a BLKmode structure being returned in registers, then use
6616 the mode computed in expand_return. */
6617 if (GET_MODE (real_decl_result) == BLKmode)
6618 PUT_MODE (real_decl_result,
6619 GET_MODE (DECL_RTL (DECL_RESULT (current_function_decl))));
6620 emit_move_insn (real_decl_result,
6621 DECL_RTL (DECL_RESULT (current_function_decl)));
6623 /* The delay slot scheduler assumes that current_function_return_rtx
6624 holds the hard register containing the return value, not a temporary
6626 current_function_return_rtx = real_decl_result;
6629 /* If returning a structure, arrange to return the address of the value
6630 in a place where debuggers expect to find it.
6632 If returning a structure PCC style,
6633 the caller also depends on this value.
6634 And current_function_returns_pcc_struct is not necessarily set. */
6635 if (current_function_returns_struct
6636 || current_function_returns_pcc_struct)
6638 rtx value_address = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
6639 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
6640 #ifdef FUNCTION_OUTGOING_VALUE
6642 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
6643 current_function_decl);
6646 = FUNCTION_VALUE (build_pointer_type (type),
6647 current_function_decl);
6650 /* Mark this as a function return value so integrate will delete the
6651 assignment and USE below when inlining this function. */
6652 REG_FUNCTION_VALUE_P (outgoing) = 1;
6654 emit_move_insn (outgoing, value_address);
6657 /* ??? This should no longer be necessary since stupid is no longer with
6658 us, but there are some parts of the compiler (eg reload_combine, and
6659 sh mach_dep_reorg) that still try and compute their own lifetime info
6660 instead of using the general framework. */
6661 use_return_register ();
6663 /* If this is an implementation of __throw, do what's necessary to
6664 communicate between __builtin_eh_return and the epilogue. */
6665 expand_eh_return ();
6667 /* Output a return insn if we are using one.
6668 Otherwise, let the rtl chain end here, to drop through
6669 into the epilogue. */
6674 emit_jump_insn (gen_return ());
6679 /* Fix up any gotos that jumped out to the outermost
6680 binding level of the function.
6681 Must follow emitting RETURN_LABEL. */
6683 /* If you have any cleanups to do at this point,
6684 and they need to create temporary variables,
6685 then you will lose. */
6686 expand_fixups (get_insns ());
6689 /* Extend a vector that records the INSN_UIDs of INSNS (either a
6690 sequence or a single insn). */
6693 record_insns (insns, vecp)
6697 if (GET_CODE (insns) == SEQUENCE)
6699 int len = XVECLEN (insns, 0);
6700 int i = VARRAY_SIZE (*vecp);
6702 VARRAY_GROW (*vecp, i + len);
6705 VARRAY_INT (*vecp, i) = INSN_UID (XVECEXP (insns, 0, len));
6711 int i = VARRAY_SIZE (*vecp);
6712 VARRAY_GROW (*vecp, i + 1);
6713 VARRAY_INT (*vecp, i) = INSN_UID (insns);
6717 /* Determine how many INSN_UIDs in VEC are part of INSN. */
6720 contains (insn, vec)
6726 if (GET_CODE (insn) == INSN
6727 && GET_CODE (PATTERN (insn)) == SEQUENCE)
6730 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
6731 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
6732 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
6738 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
6739 if (INSN_UID (insn) == VARRAY_INT (vec, j))
6746 prologue_epilogue_contains (insn)
6749 if (contains (insn, prologue))
6751 if (contains (insn, epilogue))
6757 sibcall_epilogue_contains (insn)
6760 if (sibcall_epilogue)
6761 return contains (insn, sibcall_epilogue);
6766 /* Insert gen_return at the end of block BB. This also means updating
6767 block_for_insn appropriately. */
6770 emit_return_into_block (bb, line_note)
6776 p = NEXT_INSN (bb->end);
6777 end = emit_jump_insn_after (gen_return (), bb->end);
6779 emit_line_note_after (NOTE_SOURCE_FILE (line_note),
6780 NOTE_LINE_NUMBER (line_note), bb->end);
6784 set_block_for_insn (p, bb);
6791 #endif /* HAVE_return */
6793 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
6794 this into place with notes indicating where the prologue ends and where
6795 the epilogue begins. Update the basic block information when possible. */
6798 thread_prologue_and_epilogue_insns (f)
6799 rtx f ATTRIBUTE_UNUSED;
6804 #ifdef HAVE_prologue
6805 rtx prologue_end = NULL_RTX;
6807 #if defined (HAVE_epilogue) || defined(HAVE_return)
6808 rtx epilogue_end = NULL_RTX;
6811 #ifdef HAVE_prologue
6815 seq = gen_prologue();
6818 /* Retain a map of the prologue insns. */
6819 if (GET_CODE (seq) != SEQUENCE)
6821 record_insns (seq, &prologue);
6822 prologue_end = emit_note (NULL, NOTE_INSN_PROLOGUE_END);
6824 seq = gen_sequence ();
6827 /* If optimization is off, and perhaps in an empty function,
6828 the entry block will have no successors. */
6829 if (ENTRY_BLOCK_PTR->succ)
6831 /* Can't deal with multiple successsors of the entry block. */
6832 if (ENTRY_BLOCK_PTR->succ->succ_next)
6835 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
6839 emit_insn_after (seq, f);
6843 /* If the exit block has no non-fake predecessors, we don't need
6845 for (e = EXIT_BLOCK_PTR->pred; e ; e = e->pred_next)
6846 if ((e->flags & EDGE_FAKE) == 0)
6852 if (optimize && HAVE_return)
6854 /* If we're allowed to generate a simple return instruction,
6855 then by definition we don't need a full epilogue. Examine
6856 the block that falls through to EXIT. If it does not
6857 contain any code, examine its predecessors and try to
6858 emit (conditional) return instructions. */
6864 for (e = EXIT_BLOCK_PTR->pred; e ; e = e->pred_next)
6865 if (e->flags & EDGE_FALLTHRU)
6871 /* Verify that there are no active instructions in the last block. */
6873 while (label && GET_CODE (label) != CODE_LABEL)
6875 if (active_insn_p (label))
6877 label = PREV_INSN (label);
6880 if (last->head == label && GET_CODE (label) == CODE_LABEL)
6882 rtx epilogue_line_note = NULL_RTX;
6884 /* Locate the line number associated with the closing brace,
6885 if we can find one. */
6886 for (seq = get_last_insn ();
6887 seq && ! active_insn_p (seq);
6888 seq = PREV_INSN (seq))
6889 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
6891 epilogue_line_note = seq;
6895 for (e = last->pred; e ; e = e_next)
6897 basic_block bb = e->src;
6900 e_next = e->pred_next;
6901 if (bb == ENTRY_BLOCK_PTR)
6905 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
6908 /* If we have an unconditional jump, we can replace that
6909 with a simple return instruction. */
6910 if (simplejump_p (jump))
6912 emit_return_into_block (bb, epilogue_line_note);
6913 flow_delete_insn (jump);
6916 /* If we have a conditional jump, we can try to replace
6917 that with a conditional return instruction. */
6918 else if (condjump_p (jump))
6922 ret = SET_SRC (PATTERN (jump));
6923 if (GET_CODE (XEXP (ret, 1)) == LABEL_REF)
6924 loc = &XEXP (ret, 1);
6926 loc = &XEXP (ret, 2);
6927 ret = gen_rtx_RETURN (VOIDmode);
6929 if (! validate_change (jump, loc, ret, 0))
6931 if (JUMP_LABEL (jump))
6932 LABEL_NUSES (JUMP_LABEL (jump))--;
6934 /* If this block has only one successor, it both jumps
6935 and falls through to the fallthru block, so we can't
6937 if (bb->succ->succ_next == NULL)
6943 /* Fix up the CFG for the successful change we just made. */
6944 redirect_edge_succ (e, EXIT_BLOCK_PTR);
6947 /* Emit a return insn for the exit fallthru block. Whether
6948 this is still reachable will be determined later. */
6950 emit_barrier_after (last->end);
6951 emit_return_into_block (last, epilogue_line_note);
6952 epilogue_end = last->end;
6957 #ifdef HAVE_epilogue
6960 /* Find the edge that falls through to EXIT. Other edges may exist
6961 due to RETURN instructions, but those don't need epilogues.
6962 There really shouldn't be a mixture -- either all should have
6963 been converted or none, however... */
6965 for (e = EXIT_BLOCK_PTR->pred; e ; e = e->pred_next)
6966 if (e->flags & EDGE_FALLTHRU)
6972 epilogue_end = emit_note (NULL, NOTE_INSN_EPILOGUE_BEG);
6974 seq = gen_epilogue ();
6975 emit_jump_insn (seq);
6977 /* Retain a map of the epilogue insns. */
6978 if (GET_CODE (seq) != SEQUENCE)
6980 record_insns (seq, &epilogue);
6982 seq = gen_sequence ();
6985 insert_insn_on_edge (seq, e);
6992 commit_edge_insertions ();
6994 #ifdef HAVE_sibcall_epilogue
6995 /* Emit sibling epilogues before any sibling call sites. */
6996 for (e = EXIT_BLOCK_PTR->pred; e ; e = e->pred_next)
6998 basic_block bb = e->src;
7003 if (GET_CODE (insn) != CALL_INSN
7004 || ! SIBLING_CALL_P (insn))
7008 seq = gen_sibcall_epilogue ();
7011 i = PREV_INSN (insn);
7012 newinsn = emit_insn_before (seq, insn);
7014 /* Update the UID to basic block map. */
7015 for (i = NEXT_INSN (i); i != insn; i = NEXT_INSN (i))
7016 set_block_for_insn (i, bb);
7018 /* Retain a map of the epilogue insns. Used in life analysis to
7019 avoid getting rid of sibcall epilogue insns. */
7020 record_insns (GET_CODE (seq) == SEQUENCE
7021 ? seq : newinsn, &sibcall_epilogue);
7025 #ifdef HAVE_prologue
7030 /* GDB handles `break f' by setting a breakpoint on the first
7031 line note after the prologue. Which means (1) that if
7032 there are line number notes before where we inserted the
7033 prologue we should move them, and (2) we should generate a
7034 note before the end of the first basic block, if there isn't
7035 one already there. */
7037 for (insn = prologue_end; insn ; insn = prev)
7039 prev = PREV_INSN (insn);
7040 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7042 /* Note that we cannot reorder the first insn in the
7043 chain, since rest_of_compilation relies on that
7044 remaining constant. */
7047 reorder_insns (insn, insn, prologue_end);
7051 /* Find the last line number note in the first block. */
7052 for (insn = BASIC_BLOCK (0)->end;
7053 insn != prologue_end;
7054 insn = PREV_INSN (insn))
7055 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7058 /* If we didn't find one, make a copy of the first line number
7062 for (insn = next_active_insn (prologue_end);
7064 insn = PREV_INSN (insn))
7065 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7067 emit_line_note_after (NOTE_SOURCE_FILE (insn),
7068 NOTE_LINE_NUMBER (insn),
7075 #ifdef HAVE_epilogue
7080 /* Similarly, move any line notes that appear after the epilogue.
7081 There is no need, however, to be quite so anal about the existance
7083 for (insn = epilogue_end; insn ; insn = next)
7085 next = NEXT_INSN (insn);
7086 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7087 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7093 /* Reposition the prologue-end and epilogue-begin notes after instruction
7094 scheduling and delayed branch scheduling. */
7097 reposition_prologue_and_epilogue_notes (f)
7098 rtx f ATTRIBUTE_UNUSED;
7100 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7103 if ((len = VARRAY_SIZE (prologue)) > 0)
7105 register rtx insn, note = 0;
7107 /* Scan from the beginning until we reach the last prologue insn.
7108 We apparently can't depend on basic_block_{head,end} after
7110 for (insn = f; len && insn; insn = NEXT_INSN (insn))
7112 if (GET_CODE (insn) == NOTE)
7114 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
7117 else if ((len -= contains (insn, prologue)) == 0)
7120 /* Find the prologue-end note if we haven't already, and
7121 move it to just after the last prologue insn. */
7124 for (note = insn; (note = NEXT_INSN (note));)
7125 if (GET_CODE (note) == NOTE
7126 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
7130 next = NEXT_INSN (note);
7132 /* Whether or not we can depend on BLOCK_HEAD,
7133 attempt to keep it up-to-date. */
7134 if (BLOCK_HEAD (0) == note)
7135 BLOCK_HEAD (0) = next;
7138 add_insn_after (note, insn);
7143 if ((len = VARRAY_SIZE (epilogue)) > 0)
7145 register rtx insn, note = 0;
7147 /* Scan from the end until we reach the first epilogue insn.
7148 We apparently can't depend on basic_block_{head,end} after
7150 for (insn = get_last_insn (); len && insn; insn = PREV_INSN (insn))
7152 if (GET_CODE (insn) == NOTE)
7154 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
7157 else if ((len -= contains (insn, epilogue)) == 0)
7159 /* Find the epilogue-begin note if we haven't already, and
7160 move it to just before the first epilogue insn. */
7163 for (note = insn; (note = PREV_INSN (note));)
7164 if (GET_CODE (note) == NOTE
7165 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
7169 /* Whether or not we can depend on BLOCK_HEAD,
7170 attempt to keep it up-to-date. */
7172 && BLOCK_HEAD (n_basic_blocks-1) == insn)
7173 BLOCK_HEAD (n_basic_blocks-1) = note;
7176 add_insn_before (note, insn);
7180 #endif /* HAVE_prologue or HAVE_epilogue */
7183 /* Mark T for GC. */
7187 struct temp_slot *t;
7191 ggc_mark_rtx (t->slot);
7192 ggc_mark_rtx (t->address);
7193 ggc_mark_tree (t->rtl_expr);
7199 /* Mark P for GC. */
7202 mark_function_status (p)
7211 ggc_mark_rtx (p->arg_offset_rtx);
7213 if (p->x_parm_reg_stack_loc)
7214 for (i = p->x_max_parm_reg, r = p->x_parm_reg_stack_loc;
7218 ggc_mark_rtx (p->return_rtx);
7219 ggc_mark_rtx (p->x_cleanup_label);
7220 ggc_mark_rtx (p->x_return_label);
7221 ggc_mark_rtx (p->x_save_expr_regs);
7222 ggc_mark_rtx (p->x_stack_slot_list);
7223 ggc_mark_rtx (p->x_parm_birth_insn);
7224 ggc_mark_rtx (p->x_tail_recursion_label);
7225 ggc_mark_rtx (p->x_tail_recursion_reentry);
7226 ggc_mark_rtx (p->internal_arg_pointer);
7227 ggc_mark_rtx (p->x_arg_pointer_save_area);
7228 ggc_mark_tree (p->x_rtl_expr_chain);
7229 ggc_mark_rtx (p->x_last_parm_insn);
7230 ggc_mark_tree (p->x_context_display);
7231 ggc_mark_tree (p->x_trampoline_list);
7232 ggc_mark_rtx (p->epilogue_delay_list);
7234 mark_temp_slot (p->x_temp_slots);
7237 struct var_refs_queue *q = p->fixup_var_refs_queue;
7240 ggc_mark_rtx (q->modified);
7245 ggc_mark_rtx (p->x_nonlocal_goto_handler_slots);
7246 ggc_mark_rtx (p->x_nonlocal_goto_handler_labels);
7247 ggc_mark_rtx (p->x_nonlocal_goto_stack_level);
7248 ggc_mark_tree (p->x_nonlocal_labels);
7251 /* Mark the function chain ARG (which is really a struct function **)
7255 mark_function_chain (arg)
7258 struct function *f = *(struct function **) arg;
7260 for (; f; f = f->next_global)
7262 ggc_mark_tree (f->decl);
7264 mark_function_status (f);
7265 mark_eh_status (f->eh);
7266 mark_stmt_status (f->stmt);
7267 mark_expr_status (f->expr);
7268 mark_emit_status (f->emit);
7269 mark_varasm_status (f->varasm);
7271 if (mark_machine_status)
7272 (*mark_machine_status) (f);
7273 if (mark_lang_status)
7274 (*mark_lang_status) (f);
7276 if (f->original_arg_vector)
7277 ggc_mark_rtvec ((rtvec) f->original_arg_vector);
7278 if (f->original_decl_initial)
7279 ggc_mark_tree (f->original_decl_initial);
7283 /* Called once, at initialization, to initialize function.c. */
7286 init_function_once ()
7288 ggc_add_root (&all_functions, 1, sizeof all_functions,
7289 mark_function_chain);
7291 VARRAY_INT_INIT (prologue, 0, "prologue");
7292 VARRAY_INT_INIT (epilogue, 0, "epilogue");
7293 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");