1 /* Expands front end tree to back end RTL for GNU C-Compiler
2 Copyright (C) 1987, 88, 89, 91-98, 1999 Free Software Foundation, Inc.
4 This file is part of GNU CC.
6 GNU CC is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 GNU CC is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GNU CC; see the file COPYING. If not, write to
18 the Free Software Foundation, 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
22 /* This file handles the generation of rtl code from tree structure
23 at the level of the function as a whole.
24 It creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 `expand_function_start' is called at the beginning of a function,
28 before the function body is parsed, and `expand_function_end' is
29 called after parsing the body.
31 Call `assign_stack_local' to allocate a stack slot for a local variable.
32 This is usually done during the RTL generation for the function body,
33 but it can also be done in the reload pass when a pseudo-register does
34 not get a hard register.
36 Call `put_var_into_stack' when you learn, belatedly, that a variable
37 previously given a pseudo-register must in fact go in the stack.
38 This function changes the DECL_RTL to be a stack slot instead of a reg
39 then scans all the RTL instructions so far generated to correct them. */
48 #include "insn-flags.h"
50 #include "insn-codes.h"
52 #include "hard-reg-set.h"
53 #include "insn-config.h"
56 #include "basic-block.h"
63 #ifndef TRAMPOLINE_ALIGNMENT
64 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
67 #ifndef LOCAL_ALIGNMENT
68 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
71 /* Some systems use __main in a way incompatible with its use in gcc, in these
72 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
73 give the same symbol without quotes for an alternative entry point. You
74 must define both, or neither. */
76 #define NAME__MAIN "__main"
77 #define SYMBOL__MAIN __main
80 /* Round a value to the lowest integer less than it that is a multiple of
81 the required alignment. Avoid using division in case the value is
82 negative. Assume the alignment is a power of two. */
83 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
85 /* Similar, but round to the next highest integer that meets the
87 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
89 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
90 during rtl generation. If they are different register numbers, this is
91 always true. It may also be true if
92 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
93 generation. See fix_lexical_addr for details. */
95 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
96 #define NEED_SEPARATE_AP
99 /* Nonzero if function being compiled doesn't contain any calls
100 (ignoring the prologue and epilogue). This is set prior to
101 local register allocation and is valid for the remaining
103 int current_function_is_leaf;
105 /* Nonzero if function being compiled doesn't modify the stack pointer
106 (ignoring the prologue and epilogue). This is only valid after
107 life_analysis has run. */
108 int current_function_sp_is_unchanging;
110 /* Nonzero if the function being compiled is a leaf function which only
111 uses leaf registers. This is valid after reload (specifically after
112 sched2) and is useful only if the port defines LEAF_REGISTERS. */
113 int current_function_uses_only_leaf_regs;
115 /* Nonzero once virtual register instantiation has been done.
116 assign_stack_local uses frame_pointer_rtx when this is nonzero. */
117 static int virtuals_instantiated;
119 /* These variables hold pointers to functions to
120 save and restore machine-specific data,
121 in push_function_context and pop_function_context. */
122 void (*init_machine_status) PROTO((struct function *));
123 void (*save_machine_status) PROTO((struct function *));
124 void (*restore_machine_status) PROTO((struct function *));
125 void (*mark_machine_status) PROTO((struct function *));
126 void (*free_machine_status) PROTO((struct function *));
128 /* Likewise, but for language-specific data. */
129 void (*init_lang_status) PROTO((struct function *));
130 void (*save_lang_status) PROTO((struct function *));
131 void (*restore_lang_status) PROTO((struct function *));
132 void (*mark_lang_status) PROTO((struct function *));
133 void (*free_lang_status) PROTO((struct function *));
135 /* The FUNCTION_DECL for an inline function currently being expanded. */
136 tree inline_function_decl;
138 /* The currently compiled function. */
139 struct function *current_function = 0;
141 /* Global list of all compiled functions. */
142 struct function *all_functions = 0;
144 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
145 static int *prologue;
146 static int *epilogue;
148 /* In order to evaluate some expressions, such as function calls returning
149 structures in memory, we need to temporarily allocate stack locations.
150 We record each allocated temporary in the following structure.
152 Associated with each temporary slot is a nesting level. When we pop up
153 one level, all temporaries associated with the previous level are freed.
154 Normally, all temporaries are freed after the execution of the statement
155 in which they were created. However, if we are inside a ({...}) grouping,
156 the result may be in a temporary and hence must be preserved. If the
157 result could be in a temporary, we preserve it if we can determine which
158 one it is in. If we cannot determine which temporary may contain the
159 result, all temporaries are preserved. A temporary is preserved by
160 pretending it was allocated at the previous nesting level.
162 Automatic variables are also assigned temporary slots, at the nesting
163 level where they are defined. They are marked a "kept" so that
164 free_temp_slots will not free them. */
168 /* Points to next temporary slot. */
169 struct temp_slot *next;
170 /* The rtx to used to reference the slot. */
172 /* The rtx used to represent the address if not the address of the
173 slot above. May be an EXPR_LIST if multiple addresses exist. */
175 /* The alignment (in bits) of the slot. */
177 /* The size, in units, of the slot. */
179 /* The alias set for the slot. If the alias set is zero, we don't
180 know anything about the alias set of the slot. We must only
181 reuse a slot if it is assigned an object of the same alias set.
182 Otherwise, the rest of the compiler may assume that the new use
183 of the slot cannot alias the old use of the slot, which is
184 false. If the slot has alias set zero, then we can't reuse the
185 slot at all, since we have no idea what alias set may have been
186 imposed on the memory. For example, if the stack slot is the
187 call frame for an inline functioned, we have no idea what alias
188 sets will be assigned to various pieces of the call frame. */
190 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
192 /* Non-zero if this temporary is currently in use. */
194 /* Non-zero if this temporary has its address taken. */
196 /* Nesting level at which this slot is being used. */
198 /* Non-zero if this should survive a call to free_temp_slots. */
200 /* The offset of the slot from the frame_pointer, including extra space
201 for alignment. This info is for combine_temp_slots. */
202 HOST_WIDE_INT base_offset;
203 /* The size of the slot, including extra space for alignment. This
204 info is for combine_temp_slots. */
205 HOST_WIDE_INT full_size;
208 /* This structure is used to record MEMs or pseudos used to replace VAR, any
209 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
210 maintain this list in case two operands of an insn were required to match;
211 in that case we must ensure we use the same replacement. */
213 struct fixup_replacement
217 struct fixup_replacement *next;
220 struct insns_for_mem_entry {
221 /* The KEY in HE will be a MEM. */
222 struct hash_entry he;
223 /* These are the INSNS which reference the MEM. */
227 /* Forward declarations. */
229 static rtx assign_stack_local_1 PROTO ((enum machine_mode, HOST_WIDE_INT,
230 int, struct function *));
231 static rtx assign_stack_temp_for_type PROTO ((enum machine_mode, HOST_WIDE_INT,
233 static struct temp_slot *find_temp_slot_from_address PROTO((rtx));
234 static void put_reg_into_stack PROTO((struct function *, rtx, tree,
235 enum machine_mode, enum machine_mode,
237 struct hash_table *));
238 static void fixup_var_refs PROTO((rtx, enum machine_mode, int,
239 struct hash_table *));
240 static struct fixup_replacement
241 *find_fixup_replacement PROTO((struct fixup_replacement **, rtx));
242 static void fixup_var_refs_insns PROTO((rtx, enum machine_mode, int,
243 rtx, int, struct hash_table *));
244 static void fixup_var_refs_1 PROTO((rtx, enum machine_mode, rtx *, rtx,
245 struct fixup_replacement **));
246 static rtx fixup_memory_subreg PROTO((rtx, rtx, int));
247 static rtx walk_fixup_memory_subreg PROTO((rtx, rtx, int));
248 static rtx fixup_stack_1 PROTO((rtx, rtx));
249 static void optimize_bit_field PROTO((rtx, rtx, rtx *));
250 static void instantiate_decls PROTO((tree, int));
251 static void instantiate_decls_1 PROTO((tree, int));
252 static void instantiate_decl PROTO((rtx, int, int));
253 static int instantiate_virtual_regs_1 PROTO((rtx *, rtx, int));
254 static void delete_handlers PROTO((void));
255 static void pad_to_arg_alignment PROTO((struct args_size *, int));
256 #ifndef ARGS_GROW_DOWNWARD
257 static void pad_below PROTO((struct args_size *, enum machine_mode,
260 #ifdef ARGS_GROW_DOWNWARD
261 static tree round_down PROTO((tree, int));
263 static rtx round_trampoline_addr PROTO((rtx));
264 static tree blocks_nreverse PROTO((tree));
265 static int all_blocks PROTO((tree, tree *));
266 /* We always define `record_insns' even if its not used so that we
267 can always export `prologue_epilogue_contains'. */
268 static int *record_insns PROTO((rtx)) ATTRIBUTE_UNUSED;
269 static int contains PROTO((rtx, int *));
270 static void put_addressof_into_stack PROTO((rtx, struct hash_table *));
271 static void purge_addressof_1 PROTO((rtx *, rtx, int, int,
272 struct hash_table *));
273 static struct hash_entry *insns_for_mem_newfunc PROTO((struct hash_entry *,
276 static unsigned long insns_for_mem_hash PROTO ((hash_table_key));
277 static boolean insns_for_mem_comp PROTO ((hash_table_key, hash_table_key));
278 static int insns_for_mem_walk PROTO ((rtx *, void *));
279 static void compute_insns_for_mem PROTO ((rtx, rtx, struct hash_table *));
280 static void mark_temp_slot PROTO ((struct temp_slot *));
281 static void mark_function_status PROTO ((struct function *));
282 static void mark_function_chain PROTO ((void *));
283 static void prepare_function_start PROTO ((void));
286 /* Pointer to chain of `struct function' for containing functions. */
287 struct function *outer_function_chain;
289 /* Given a function decl for a containing function,
290 return the `struct function' for it. */
293 find_function_data (decl)
298 for (p = outer_function_chain; p; p = p->next)
305 /* Save the current context for compilation of a nested function.
306 This is called from language-specific code. The caller should use
307 the save_lang_status callback to save any language-specific state,
308 since this function knows only about language-independent
312 push_function_context_to (context)
315 struct function *p, *context_data;
319 context_data = (context == current_function_decl
321 : find_function_data (context));
322 context_data->contains_functions = 1;
325 if (current_function == 0)
326 init_dummy_function_start ();
327 p = current_function;
329 p->next = outer_function_chain;
330 outer_function_chain = p;
331 p->fixup_var_refs_queue = 0;
333 save_tree_status (p);
334 if (save_lang_status)
335 (*save_lang_status) (p);
336 if (save_machine_status)
337 (*save_machine_status) (p);
339 current_function = 0;
343 push_function_context ()
345 push_function_context_to (current_function_decl);
348 /* Restore the last saved context, at the end of a nested function.
349 This function is called from language-specific code. */
352 pop_function_context_from (context)
353 tree context ATTRIBUTE_UNUSED;
355 struct function *p = outer_function_chain;
356 struct var_refs_queue *queue;
357 struct var_refs_queue *next;
359 current_function = p;
360 outer_function_chain = p->next;
362 current_function_decl = p->decl;
365 restore_tree_status (p);
366 restore_emit_status (p);
368 if (restore_machine_status)
369 (*restore_machine_status) (p);
370 if (restore_lang_status)
371 (*restore_lang_status) (p);
373 /* Finish doing put_var_into_stack for any of our variables
374 which became addressable during the nested function. */
375 for (queue = p->fixup_var_refs_queue; queue; queue = next)
378 fixup_var_refs (queue->modified, queue->promoted_mode,
379 queue->unsignedp, 0);
382 p->fixup_var_refs_queue = 0;
384 /* Reset variables that have known state during rtx generation. */
385 rtx_equal_function_value_matters = 1;
386 virtuals_instantiated = 0;
390 pop_function_context ()
392 pop_function_context_from (current_function_decl);
395 /* Clear out all parts of the state in F that can safely be discarded
396 after the function has been parsed, but not compiled, to let
397 garbage collection reclaim the memory. */
400 free_after_parsing (f)
403 /* f->expr->forced_labels is used by code generation. */
404 /* f->emit->regno_reg_rtx is used by code generation. */
405 /* f->varasm is used by code generation. */
406 /* f->eh->eh_return_stub_label is used by code generation. */
408 if (free_lang_status)
409 (*free_lang_status) (f);
410 free_stmt_status (f);
413 /* Clear out all parts of the state in F that can safely be discarded
414 after the function has been compiled, to let garbage collection
415 reclaim the memory. */
418 free_after_compilation (f)
422 free_expr_status (f);
423 free_emit_status (f);
424 free_varasm_status (f);
426 if (free_machine_status)
427 (*free_machine_status) (f);
429 if (f->x_parm_reg_stack_loc)
430 free (f->x_parm_reg_stack_loc);
432 f->arg_offset_rtx = NULL;
433 f->return_rtx = NULL;
434 f->internal_arg_pointer = NULL;
435 f->x_nonlocal_labels = NULL;
436 f->x_nonlocal_goto_handler_slots = NULL;
437 f->x_nonlocal_goto_handler_labels = NULL;
438 f->x_nonlocal_goto_stack_level = NULL;
439 f->x_cleanup_label = NULL;
440 f->x_return_label = NULL;
441 f->x_save_expr_regs = NULL;
442 f->x_stack_slot_list = NULL;
443 f->x_rtl_expr_chain = NULL;
444 f->x_tail_recursion_label = NULL;
445 f->x_tail_recursion_reentry = NULL;
446 f->x_arg_pointer_save_area = NULL;
447 f->x_context_display = NULL;
448 f->x_trampoline_list = NULL;
449 f->x_parm_birth_insn = NULL;
450 f->x_last_parm_insn = NULL;
451 f->x_parm_reg_stack_loc = NULL;
452 f->x_temp_slots = NULL;
453 f->fixup_var_refs_queue = NULL;
454 f->original_arg_vector = NULL;
455 f->original_decl_initial = NULL;
456 f->inl_last_parm_insn = NULL;
457 f->epilogue_delay_list = NULL;
461 /* Allocate fixed slots in the stack frame of the current function. */
463 /* Return size needed for stack frame based on slots so far allocated in
465 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
466 the caller may have to do that. */
469 get_func_frame_size (f)
472 #ifdef FRAME_GROWS_DOWNWARD
473 return -f->x_frame_offset;
475 return f->x_frame_offset;
479 /* Return size needed for stack frame based on slots so far allocated.
480 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
481 the caller may have to do that. */
485 return get_func_frame_size (current_function);
488 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
489 with machine mode MODE.
491 ALIGN controls the amount of alignment for the address of the slot:
492 0 means according to MODE,
493 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
494 positive specifies alignment boundary in bits.
496 We do not round to stack_boundary here.
498 FUNCTION specifies the function to allocate in. */
501 assign_stack_local_1 (mode, size, align, function)
502 enum machine_mode mode;
505 struct function *function;
507 register rtx x, addr;
508 int bigend_correction = 0;
511 /* Allocate in the memory associated with the function in whose frame
513 if (function != current_function)
514 push_obstacks (function->function_obstack,
515 function->function_maybepermanent_obstack);
521 alignment = GET_MODE_ALIGNMENT (mode);
523 alignment = BIGGEST_ALIGNMENT;
525 /* Allow the target to (possibly) increase the alignment of this
527 type = type_for_mode (mode, 0);
529 alignment = LOCAL_ALIGNMENT (type, alignment);
531 alignment /= BITS_PER_UNIT;
533 else if (align == -1)
535 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
536 size = CEIL_ROUND (size, alignment);
539 alignment = align / BITS_PER_UNIT;
541 #ifdef FRAME_GROWS_DOWNWARD
542 function->x_frame_offset -= size;
545 /* Round frame offset to that alignment.
546 We must be careful here, since FRAME_OFFSET might be negative and
547 division with a negative dividend isn't as well defined as we might
548 like. So we instead assume that ALIGNMENT is a power of two and
549 use logical operations which are unambiguous. */
550 #ifdef FRAME_GROWS_DOWNWARD
551 function->x_frame_offset = FLOOR_ROUND (function->x_frame_offset, alignment);
553 function->x_frame_offset = CEIL_ROUND (function->x_frame_offset, alignment);
556 /* On a big-endian machine, if we are allocating more space than we will use,
557 use the least significant bytes of those that are allocated. */
558 if (BYTES_BIG_ENDIAN && mode != BLKmode)
559 bigend_correction = size - GET_MODE_SIZE (mode);
561 /* If we have already instantiated virtual registers, return the actual
562 address relative to the frame pointer. */
563 if (function == current_function && virtuals_instantiated)
564 addr = plus_constant (frame_pointer_rtx,
565 (frame_offset + bigend_correction
566 + STARTING_FRAME_OFFSET));
568 addr = plus_constant (virtual_stack_vars_rtx,
569 function->x_frame_offset + bigend_correction);
571 #ifndef FRAME_GROWS_DOWNWARD
572 function->x_frame_offset += size;
575 x = gen_rtx_MEM (mode, addr);
577 function->x_stack_slot_list
578 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
580 if (function != current_function)
586 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
589 assign_stack_local (mode, size, align)
590 enum machine_mode mode;
594 return assign_stack_local_1 (mode, size, align, current_function);
597 /* Allocate a temporary stack slot and record it for possible later
600 MODE is the machine mode to be given to the returned rtx.
602 SIZE is the size in units of the space required. We do no rounding here
603 since assign_stack_local will do any required rounding.
605 KEEP is 1 if this slot is to be retained after a call to
606 free_temp_slots. Automatic variables for a block are allocated
607 with this flag. KEEP is 2 if we allocate a longer term temporary,
608 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
609 if we are to allocate something at an inner level to be treated as
610 a variable in the block (e.g., a SAVE_EXPR).
612 TYPE is the type that will be used for the stack slot. */
615 assign_stack_temp_for_type (mode, size, keep, type)
616 enum machine_mode mode;
623 struct temp_slot *p, *best_p = 0;
625 /* If SIZE is -1 it means that somebody tried to allocate a temporary
626 of a variable size. */
630 /* If we know the alias set for the memory that will be used, use
631 it. If there's no TYPE, then we don't know anything about the
632 alias set for the memory. */
634 alias_set = get_alias_set (type);
638 align = GET_MODE_ALIGNMENT (mode);
640 align = BIGGEST_ALIGNMENT;
643 type = type_for_mode (mode, 0);
645 align = LOCAL_ALIGNMENT (type, align);
647 /* Try to find an available, already-allocated temporary of the proper
648 mode which meets the size and alignment requirements. Choose the
649 smallest one with the closest alignment. */
650 for (p = temp_slots; p; p = p->next)
651 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
653 && (!flag_strict_aliasing
654 || (alias_set && p->alias_set == alias_set))
655 && (best_p == 0 || best_p->size > p->size
656 || (best_p->size == p->size && best_p->align > p->align)))
658 if (p->align == align && p->size == size)
666 /* Make our best, if any, the one to use. */
669 /* If there are enough aligned bytes left over, make them into a new
670 temp_slot so that the extra bytes don't get wasted. Do this only
671 for BLKmode slots, so that we can be sure of the alignment. */
672 if (GET_MODE (best_p->slot) == BLKmode
673 /* We can't split slots if -fstrict-aliasing because the
674 information about the alias set for the new slot will be
676 && !flag_strict_aliasing)
678 int alignment = best_p->align / BITS_PER_UNIT;
679 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
681 if (best_p->size - rounded_size >= alignment)
683 p = (struct temp_slot *) oballoc (sizeof (struct temp_slot));
684 p->in_use = p->addr_taken = 0;
685 p->size = best_p->size - rounded_size;
686 p->base_offset = best_p->base_offset + rounded_size;
687 p->full_size = best_p->full_size - rounded_size;
688 p->slot = gen_rtx_MEM (BLKmode,
689 plus_constant (XEXP (best_p->slot, 0),
691 p->align = best_p->align;
694 p->next = temp_slots;
697 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
700 best_p->size = rounded_size;
701 best_p->full_size = rounded_size;
708 /* If we still didn't find one, make a new temporary. */
711 HOST_WIDE_INT frame_offset_old = frame_offset;
713 p = (struct temp_slot *) oballoc (sizeof (struct temp_slot));
715 /* We are passing an explicit alignment request to assign_stack_local.
716 One side effect of that is assign_stack_local will not round SIZE
717 to ensure the frame offset remains suitably aligned.
719 So for requests which depended on the rounding of SIZE, we go ahead
720 and round it now. We also make sure ALIGNMENT is at least
721 BIGGEST_ALIGNMENT. */
722 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
724 p->slot = assign_stack_local (mode,
726 ? CEIL_ROUND (size, align / BITS_PER_UNIT)
731 p->alias_set = alias_set;
733 /* The following slot size computation is necessary because we don't
734 know the actual size of the temporary slot until assign_stack_local
735 has performed all the frame alignment and size rounding for the
736 requested temporary. Note that extra space added for alignment
737 can be either above or below this stack slot depending on which
738 way the frame grows. We include the extra space if and only if it
739 is above this slot. */
740 #ifdef FRAME_GROWS_DOWNWARD
741 p->size = frame_offset_old - frame_offset;
746 /* Now define the fields used by combine_temp_slots. */
747 #ifdef FRAME_GROWS_DOWNWARD
748 p->base_offset = frame_offset;
749 p->full_size = frame_offset_old - frame_offset;
751 p->base_offset = frame_offset_old;
752 p->full_size = frame_offset - frame_offset_old;
755 p->next = temp_slots;
761 p->rtl_expr = seq_rtl_expr;
765 p->level = target_temp_slot_level;
770 p->level = var_temp_slot_level;
775 p->level = temp_slot_level;
779 /* We may be reusing an old slot, so clear any MEM flags that may have been
781 RTX_UNCHANGING_P (p->slot) = 0;
782 MEM_IN_STRUCT_P (p->slot) = 0;
783 MEM_SCALAR_P (p->slot) = 0;
784 MEM_ALIAS_SET (p->slot) = 0;
788 /* Allocate a temporary stack slot and record it for possible later
789 reuse. First three arguments are same as in preceding function. */
792 assign_stack_temp (mode, size, keep)
793 enum machine_mode mode;
797 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
800 /* Assign a temporary of given TYPE.
801 KEEP is as for assign_stack_temp.
802 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
803 it is 0 if a register is OK.
804 DONT_PROMOTE is 1 if we should not promote values in register
808 assign_temp (type, keep, memory_required, dont_promote)
814 enum machine_mode mode = TYPE_MODE (type);
815 int unsignedp = TREE_UNSIGNED (type);
817 if (mode == BLKmode || memory_required)
819 HOST_WIDE_INT size = int_size_in_bytes (type);
822 /* Unfortunately, we don't yet know how to allocate variable-sized
823 temporaries. However, sometimes we have a fixed upper limit on
824 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
825 instead. This is the case for Chill variable-sized strings. */
826 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
827 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
828 && TREE_CODE (TYPE_ARRAY_MAX_SIZE (type)) == INTEGER_CST)
829 size = TREE_INT_CST_LOW (TYPE_ARRAY_MAX_SIZE (type));
831 tmp = assign_stack_temp_for_type (mode, size, keep, type);
832 MEM_SET_IN_STRUCT_P (tmp, AGGREGATE_TYPE_P (type));
836 #ifndef PROMOTE_FOR_CALL_ONLY
838 mode = promote_mode (type, mode, &unsignedp, 0);
841 return gen_reg_rtx (mode);
844 /* Combine temporary stack slots which are adjacent on the stack.
846 This allows for better use of already allocated stack space. This is only
847 done for BLKmode slots because we can be sure that we won't have alignment
848 problems in this case. */
851 combine_temp_slots ()
853 struct temp_slot *p, *q;
854 struct temp_slot *prev_p, *prev_q;
857 /* We can't combine slots, because the information about which slot
858 is in which alias set will be lost. */
859 if (flag_strict_aliasing)
862 /* If there are a lot of temp slots, don't do anything unless
863 high levels of optimizaton. */
864 if (! flag_expensive_optimizations)
865 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
866 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
869 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
873 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
874 for (q = p->next, prev_q = p; q; q = prev_q->next)
877 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
879 if (p->base_offset + p->full_size == q->base_offset)
881 /* Q comes after P; combine Q into P. */
883 p->full_size += q->full_size;
886 else if (q->base_offset + q->full_size == p->base_offset)
888 /* P comes after Q; combine P into Q. */
890 q->full_size += p->full_size;
895 /* Either delete Q or advance past it. */
897 prev_q->next = q->next;
901 /* Either delete P or advance past it. */
905 prev_p->next = p->next;
907 temp_slots = p->next;
914 /* Find the temp slot corresponding to the object at address X. */
916 static struct temp_slot *
917 find_temp_slot_from_address (x)
923 for (p = temp_slots; p; p = p->next)
928 else if (XEXP (p->slot, 0) == x
930 || (GET_CODE (x) == PLUS
931 && XEXP (x, 0) == virtual_stack_vars_rtx
932 && GET_CODE (XEXP (x, 1)) == CONST_INT
933 && INTVAL (XEXP (x, 1)) >= p->base_offset
934 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
937 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
938 for (next = p->address; next; next = XEXP (next, 1))
939 if (XEXP (next, 0) == x)
946 /* Indicate that NEW is an alternate way of referring to the temp slot
947 that previously was known by OLD. */
950 update_temp_slot_address (old, new)
953 struct temp_slot *p = find_temp_slot_from_address (old);
955 /* If none, return. Else add NEW as an alias. */
958 else if (p->address == 0)
962 if (GET_CODE (p->address) != EXPR_LIST)
963 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
965 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
969 /* If X could be a reference to a temporary slot, mark the fact that its
970 address was taken. */
973 mark_temp_addr_taken (x)
981 /* If X is not in memory or is at a constant address, it cannot be in
983 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
986 p = find_temp_slot_from_address (XEXP (x, 0));
991 /* If X could be a reference to a temporary slot, mark that slot as
992 belonging to the to one level higher than the current level. If X
993 matched one of our slots, just mark that one. Otherwise, we can't
994 easily predict which it is, so upgrade all of them. Kept slots
997 This is called when an ({...}) construct occurs and a statement
998 returns a value in memory. */
1001 preserve_temp_slots (x)
1004 struct temp_slot *p = 0;
1006 /* If there is no result, we still might have some objects whose address
1007 were taken, so we need to make sure they stay around. */
1010 for (p = temp_slots; p; p = p->next)
1011 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1017 /* If X is a register that is being used as a pointer, see if we have
1018 a temporary slot we know it points to. To be consistent with
1019 the code below, we really should preserve all non-kept slots
1020 if we can't find a match, but that seems to be much too costly. */
1021 if (GET_CODE (x) == REG && REGNO_POINTER_FLAG (REGNO (x)))
1022 p = find_temp_slot_from_address (x);
1024 /* If X is not in memory or is at a constant address, it cannot be in
1025 a temporary slot, but it can contain something whose address was
1027 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1029 for (p = temp_slots; p; p = p->next)
1030 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1036 /* First see if we can find a match. */
1038 p = find_temp_slot_from_address (XEXP (x, 0));
1042 /* Move everything at our level whose address was taken to our new
1043 level in case we used its address. */
1044 struct temp_slot *q;
1046 if (p->level == temp_slot_level)
1048 for (q = temp_slots; q; q = q->next)
1049 if (q != p && q->addr_taken && q->level == p->level)
1058 /* Otherwise, preserve all non-kept slots at this level. */
1059 for (p = temp_slots; p; p = p->next)
1060 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1064 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1065 with that RTL_EXPR, promote it into a temporary slot at the present
1066 level so it will not be freed when we free slots made in the
1070 preserve_rtl_expr_result (x)
1073 struct temp_slot *p;
1075 /* If X is not in memory or is at a constant address, it cannot be in
1076 a temporary slot. */
1077 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1080 /* If we can find a match, move it to our level unless it is already at
1082 p = find_temp_slot_from_address (XEXP (x, 0));
1085 p->level = MIN (p->level, temp_slot_level);
1092 /* Free all temporaries used so far. This is normally called at the end
1093 of generating code for a statement. Don't free any temporaries
1094 currently in use for an RTL_EXPR that hasn't yet been emitted.
1095 We could eventually do better than this since it can be reused while
1096 generating the same RTL_EXPR, but this is complex and probably not
1102 struct temp_slot *p;
1104 for (p = temp_slots; p; p = p->next)
1105 if (p->in_use && p->level == temp_slot_level && ! p->keep
1106 && p->rtl_expr == 0)
1109 combine_temp_slots ();
1112 /* Free all temporary slots used in T, an RTL_EXPR node. */
1115 free_temps_for_rtl_expr (t)
1118 struct temp_slot *p;
1120 for (p = temp_slots; p; p = p->next)
1121 if (p->rtl_expr == t)
1124 combine_temp_slots ();
1127 /* Mark all temporaries ever allocated in this function as not suitable
1128 for reuse until the current level is exited. */
1131 mark_all_temps_used ()
1133 struct temp_slot *p;
1135 for (p = temp_slots; p; p = p->next)
1137 p->in_use = p->keep = 1;
1138 p->level = MIN (p->level, temp_slot_level);
1142 /* Push deeper into the nesting level for stack temporaries. */
1150 /* Likewise, but save the new level as the place to allocate variables
1155 push_temp_slots_for_block ()
1159 var_temp_slot_level = temp_slot_level;
1162 /* Likewise, but save the new level as the place to allocate temporaries
1163 for TARGET_EXPRs. */
1166 push_temp_slots_for_target ()
1170 target_temp_slot_level = temp_slot_level;
1173 /* Set and get the value of target_temp_slot_level. The only
1174 permitted use of these functions is to save and restore this value. */
1177 get_target_temp_slot_level ()
1179 return target_temp_slot_level;
1183 set_target_temp_slot_level (level)
1186 target_temp_slot_level = level;
1190 /* Pop a temporary nesting level. All slots in use in the current level
1196 struct temp_slot *p;
1198 for (p = temp_slots; p; p = p->next)
1199 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1202 combine_temp_slots ();
1207 /* Initialize temporary slots. */
1212 /* We have not allocated any temporaries yet. */
1214 temp_slot_level = 0;
1215 var_temp_slot_level = 0;
1216 target_temp_slot_level = 0;
1219 /* Retroactively move an auto variable from a register to a stack slot.
1220 This is done when an address-reference to the variable is seen. */
1223 put_var_into_stack (decl)
1227 enum machine_mode promoted_mode, decl_mode;
1228 struct function *function = 0;
1230 int can_use_addressof;
1232 context = decl_function_context (decl);
1234 /* Get the current rtl used for this object and its original mode. */
1235 reg = TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl) : DECL_RTL (decl);
1237 /* No need to do anything if decl has no rtx yet
1238 since in that case caller is setting TREE_ADDRESSABLE
1239 and a stack slot will be assigned when the rtl is made. */
1243 /* Get the declared mode for this object. */
1244 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1245 : DECL_MODE (decl));
1246 /* Get the mode it's actually stored in. */
1247 promoted_mode = GET_MODE (reg);
1249 /* If this variable comes from an outer function,
1250 find that function's saved context. */
1251 if (context != current_function_decl && context != inline_function_decl)
1252 for (function = outer_function_chain; function; function = function->next)
1253 if (function->decl == context)
1256 /* If this is a variable-size object with a pseudo to address it,
1257 put that pseudo into the stack, if the var is nonlocal. */
1258 if (DECL_NONLOCAL (decl)
1259 && GET_CODE (reg) == MEM
1260 && GET_CODE (XEXP (reg, 0)) == REG
1261 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1263 reg = XEXP (reg, 0);
1264 decl_mode = promoted_mode = GET_MODE (reg);
1270 /* FIXME make it work for promoted modes too */
1271 && decl_mode == promoted_mode
1272 #ifdef NON_SAVING_SETJMP
1273 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1277 /* If we can't use ADDRESSOF, make sure we see through one we already
1279 if (! can_use_addressof && GET_CODE (reg) == MEM
1280 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1281 reg = XEXP (XEXP (reg, 0), 0);
1283 /* Now we should have a value that resides in one or more pseudo regs. */
1285 if (GET_CODE (reg) == REG)
1287 /* If this variable lives in the current function and we don't need
1288 to put things in the stack for the sake of setjmp, try to keep it
1289 in a register until we know we actually need the address. */
1290 if (can_use_addressof)
1291 gen_mem_addressof (reg, decl);
1293 put_reg_into_stack (function, reg, TREE_TYPE (decl),
1294 promoted_mode, decl_mode,
1295 TREE_SIDE_EFFECTS (decl), 0,
1296 TREE_USED (decl) || DECL_INITIAL (decl) != 0,
1299 else if (GET_CODE (reg) == CONCAT)
1301 /* A CONCAT contains two pseudos; put them both in the stack.
1302 We do it so they end up consecutive. */
1303 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1304 tree part_type = TREE_TYPE (TREE_TYPE (decl));
1305 #ifdef FRAME_GROWS_DOWNWARD
1306 /* Since part 0 should have a lower address, do it second. */
1307 put_reg_into_stack (function, XEXP (reg, 1), part_type, part_mode,
1308 part_mode, TREE_SIDE_EFFECTS (decl), 0,
1309 TREE_USED (decl) || DECL_INITIAL (decl) != 0,
1311 put_reg_into_stack (function, XEXP (reg, 0), part_type, part_mode,
1312 part_mode, TREE_SIDE_EFFECTS (decl), 0,
1313 TREE_USED (decl) || DECL_INITIAL (decl) != 0,
1316 put_reg_into_stack (function, XEXP (reg, 0), part_type, part_mode,
1317 part_mode, TREE_SIDE_EFFECTS (decl), 0,
1318 TREE_USED (decl) || DECL_INITIAL (decl) != 0,
1320 put_reg_into_stack (function, XEXP (reg, 1), part_type, part_mode,
1321 part_mode, TREE_SIDE_EFFECTS (decl), 0,
1322 TREE_USED (decl) || DECL_INITIAL (decl) != 0,
1326 /* Change the CONCAT into a combined MEM for both parts. */
1327 PUT_CODE (reg, MEM);
1328 MEM_VOLATILE_P (reg) = MEM_VOLATILE_P (XEXP (reg, 0));
1329 MEM_ALIAS_SET (reg) = get_alias_set (decl);
1331 /* The two parts are in memory order already.
1332 Use the lower parts address as ours. */
1333 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1334 /* Prevent sharing of rtl that might lose. */
1335 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1336 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1341 if (current_function_check_memory_usage)
1342 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
1343 XEXP (reg, 0), Pmode,
1344 GEN_INT (GET_MODE_SIZE (GET_MODE (reg))),
1345 TYPE_MODE (sizetype),
1346 GEN_INT (MEMORY_USE_RW),
1347 TYPE_MODE (integer_type_node));
1350 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1351 into the stack frame of FUNCTION (0 means the current function).
1352 DECL_MODE is the machine mode of the user-level data type.
1353 PROMOTED_MODE is the machine mode of the register.
1354 VOLATILE_P is nonzero if this is for a "volatile" decl.
1355 USED_P is nonzero if this reg might have already been used in an insn. */
1358 put_reg_into_stack (function, reg, type, promoted_mode, decl_mode, volatile_p,
1359 original_regno, used_p, ht)
1360 struct function *function;
1363 enum machine_mode promoted_mode, decl_mode;
1367 struct hash_table *ht;
1369 struct function *func = function ? function : current_function;
1371 int regno = original_regno;
1374 regno = REGNO (reg);
1376 if (regno < func->x_max_parm_reg)
1377 new = func->x_parm_reg_stack_loc[regno];
1379 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode), 0, func);
1381 PUT_CODE (reg, MEM);
1382 PUT_MODE (reg, decl_mode);
1383 XEXP (reg, 0) = XEXP (new, 0);
1384 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1385 MEM_VOLATILE_P (reg) = volatile_p;
1387 /* If this is a memory ref that contains aggregate components,
1388 mark it as such for cse and loop optimize. If we are reusing a
1389 previously generated stack slot, then we need to copy the bit in
1390 case it was set for other reasons. For instance, it is set for
1391 __builtin_va_alist. */
1392 MEM_SET_IN_STRUCT_P (reg,
1393 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1394 MEM_ALIAS_SET (reg) = get_alias_set (type);
1396 /* Now make sure that all refs to the variable, previously made
1397 when it was a register, are fixed up to be valid again. */
1399 if (used_p && function != 0)
1401 struct var_refs_queue *temp;
1404 = (struct var_refs_queue *) xmalloc (sizeof (struct var_refs_queue));
1405 temp->modified = reg;
1406 temp->promoted_mode = promoted_mode;
1407 temp->unsignedp = TREE_UNSIGNED (type);
1408 temp->next = function->fixup_var_refs_queue;
1409 function->fixup_var_refs_queue = temp;
1412 /* Variable is local; fix it up now. */
1413 fixup_var_refs (reg, promoted_mode, TREE_UNSIGNED (type), ht);
1417 fixup_var_refs (var, promoted_mode, unsignedp, ht)
1419 enum machine_mode promoted_mode;
1421 struct hash_table *ht;
1424 rtx first_insn = get_insns ();
1425 struct sequence_stack *stack = seq_stack;
1426 tree rtl_exps = rtl_expr_chain;
1428 /* Must scan all insns for stack-refs that exceed the limit. */
1429 fixup_var_refs_insns (var, promoted_mode, unsignedp, first_insn,
1431 /* If there's a hash table, it must record all uses of VAR. */
1435 /* Scan all pending sequences too. */
1436 for (; stack; stack = stack->next)
1438 push_to_sequence (stack->first);
1439 fixup_var_refs_insns (var, promoted_mode, unsignedp,
1440 stack->first, stack->next != 0, 0);
1441 /* Update remembered end of sequence
1442 in case we added an insn at the end. */
1443 stack->last = get_last_insn ();
1447 /* Scan all waiting RTL_EXPRs too. */
1448 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1450 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1451 if (seq != const0_rtx && seq != 0)
1453 push_to_sequence (seq);
1454 fixup_var_refs_insns (var, promoted_mode, unsignedp, seq, 0,
1460 /* Scan the catch clauses for exception handling too. */
1461 push_to_sequence (catch_clauses);
1462 fixup_var_refs_insns (var, promoted_mode, unsignedp, catch_clauses,
1467 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1468 some part of an insn. Return a struct fixup_replacement whose OLD
1469 value is equal to X. Allocate a new structure if no such entry exists. */
1471 static struct fixup_replacement *
1472 find_fixup_replacement (replacements, x)
1473 struct fixup_replacement **replacements;
1476 struct fixup_replacement *p;
1478 /* See if we have already replaced this. */
1479 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1484 p = (struct fixup_replacement *) oballoc (sizeof (struct fixup_replacement));
1487 p->next = *replacements;
1494 /* Scan the insn-chain starting with INSN for refs to VAR
1495 and fix them up. TOPLEVEL is nonzero if this chain is the
1496 main chain of insns for the current function. */
1499 fixup_var_refs_insns (var, promoted_mode, unsignedp, insn, toplevel, ht)
1501 enum machine_mode promoted_mode;
1505 struct hash_table *ht;
1508 rtx insn_list = NULL_RTX;
1510 /* If we already know which INSNs reference VAR there's no need
1511 to walk the entire instruction chain. */
1514 insn_list = ((struct insns_for_mem_entry *)
1515 hash_lookup (ht, var, /*create=*/0, /*copy=*/0))->insns;
1516 insn = insn_list ? XEXP (insn_list, 0) : NULL_RTX;
1517 insn_list = XEXP (insn_list, 1);
1522 rtx next = NEXT_INSN (insn);
1523 rtx set, prev, prev_set;
1526 if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
1528 /* Remember the notes in case we delete the insn. */
1529 note = REG_NOTES (insn);
1531 /* If this is a CLOBBER of VAR, delete it.
1533 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1534 and REG_RETVAL notes too. */
1535 if (GET_CODE (PATTERN (insn)) == CLOBBER
1536 && (XEXP (PATTERN (insn), 0) == var
1537 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1538 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1539 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1541 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1542 /* The REG_LIBCALL note will go away since we are going to
1543 turn INSN into a NOTE, so just delete the
1544 corresponding REG_RETVAL note. */
1545 remove_note (XEXP (note, 0),
1546 find_reg_note (XEXP (note, 0), REG_RETVAL,
1549 /* In unoptimized compilation, we shouldn't call delete_insn
1550 except in jump.c doing warnings. */
1551 PUT_CODE (insn, NOTE);
1552 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1553 NOTE_SOURCE_FILE (insn) = 0;
1556 /* The insn to load VAR from a home in the arglist
1557 is now a no-op. When we see it, just delete it.
1558 Similarly if this is storing VAR from a register from which
1559 it was loaded in the previous insn. This will occur
1560 when an ADDRESSOF was made for an arglist slot. */
1562 && (set = single_set (insn)) != 0
1563 && SET_DEST (set) == var
1564 /* If this represents the result of an insn group,
1565 don't delete the insn. */
1566 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1567 && (rtx_equal_p (SET_SRC (set), var)
1568 || (GET_CODE (SET_SRC (set)) == REG
1569 && (prev = prev_nonnote_insn (insn)) != 0
1570 && (prev_set = single_set (prev)) != 0
1571 && SET_DEST (prev_set) == SET_SRC (set)
1572 && rtx_equal_p (SET_SRC (prev_set), var))))
1574 /* In unoptimized compilation, we shouldn't call delete_insn
1575 except in jump.c doing warnings. */
1576 PUT_CODE (insn, NOTE);
1577 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1578 NOTE_SOURCE_FILE (insn) = 0;
1579 if (insn == last_parm_insn)
1580 last_parm_insn = PREV_INSN (next);
1584 struct fixup_replacement *replacements = 0;
1585 rtx next_insn = NEXT_INSN (insn);
1587 if (SMALL_REGISTER_CLASSES)
1589 /* If the insn that copies the results of a CALL_INSN
1590 into a pseudo now references VAR, we have to use an
1591 intermediate pseudo since we want the life of the
1592 return value register to be only a single insn.
1594 If we don't use an intermediate pseudo, such things as
1595 address computations to make the address of VAR valid
1596 if it is not can be placed between the CALL_INSN and INSN.
1598 To make sure this doesn't happen, we record the destination
1599 of the CALL_INSN and see if the next insn uses both that
1602 if (call_dest != 0 && GET_CODE (insn) == INSN
1603 && reg_mentioned_p (var, PATTERN (insn))
1604 && reg_mentioned_p (call_dest, PATTERN (insn)))
1606 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1608 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1610 PATTERN (insn) = replace_rtx (PATTERN (insn),
1614 if (GET_CODE (insn) == CALL_INSN
1615 && GET_CODE (PATTERN (insn)) == SET)
1616 call_dest = SET_DEST (PATTERN (insn));
1617 else if (GET_CODE (insn) == CALL_INSN
1618 && GET_CODE (PATTERN (insn)) == PARALLEL
1619 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1620 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1625 /* See if we have to do anything to INSN now that VAR is in
1626 memory. If it needs to be loaded into a pseudo, use a single
1627 pseudo for the entire insn in case there is a MATCH_DUP
1628 between two operands. We pass a pointer to the head of
1629 a list of struct fixup_replacements. If fixup_var_refs_1
1630 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1631 it will record them in this list.
1633 If it allocated a pseudo for any replacement, we copy into
1636 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1639 /* If this is last_parm_insn, and any instructions were output
1640 after it to fix it up, then we must set last_parm_insn to
1641 the last such instruction emitted. */
1642 if (insn == last_parm_insn)
1643 last_parm_insn = PREV_INSN (next_insn);
1645 while (replacements)
1647 if (GET_CODE (replacements->new) == REG)
1652 /* OLD might be a (subreg (mem)). */
1653 if (GET_CODE (replacements->old) == SUBREG)
1655 = fixup_memory_subreg (replacements->old, insn, 0);
1658 = fixup_stack_1 (replacements->old, insn);
1660 insert_before = insn;
1662 /* If we are changing the mode, do a conversion.
1663 This might be wasteful, but combine.c will
1664 eliminate much of the waste. */
1666 if (GET_MODE (replacements->new)
1667 != GET_MODE (replacements->old))
1670 convert_move (replacements->new,
1671 replacements->old, unsignedp);
1672 seq = gen_sequence ();
1676 seq = gen_move_insn (replacements->new,
1679 emit_insn_before (seq, insert_before);
1682 replacements = replacements->next;
1686 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1687 But don't touch other insns referred to by reg-notes;
1688 we will get them elsewhere. */
1691 if (GET_CODE (note) != INSN_LIST)
1693 = walk_fixup_memory_subreg (XEXP (note, 0), insn, 1);
1694 note = XEXP (note, 1);
1702 insn = XEXP (insn_list, 0);
1703 insn_list = XEXP (insn_list, 1);
1710 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1711 See if the rtx expression at *LOC in INSN needs to be changed.
1713 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1714 contain a list of original rtx's and replacements. If we find that we need
1715 to modify this insn by replacing a memory reference with a pseudo or by
1716 making a new MEM to implement a SUBREG, we consult that list to see if
1717 we have already chosen a replacement. If none has already been allocated,
1718 we allocate it and update the list. fixup_var_refs_insns will copy VAR
1719 or the SUBREG, as appropriate, to the pseudo. */
1722 fixup_var_refs_1 (var, promoted_mode, loc, insn, replacements)
1724 enum machine_mode promoted_mode;
1727 struct fixup_replacement **replacements;
1730 register rtx x = *loc;
1731 RTX_CODE code = GET_CODE (x);
1732 register const char *fmt;
1733 register rtx tem, tem1;
1734 struct fixup_replacement *replacement;
1739 if (XEXP (x, 0) == var)
1741 /* Prevent sharing of rtl that might lose. */
1742 rtx sub = copy_rtx (XEXP (var, 0));
1744 if (! validate_change (insn, loc, sub, 0))
1746 rtx y = gen_reg_rtx (GET_MODE (sub));
1749 /* We should be able to replace with a register or all is lost.
1750 Note that we can't use validate_change to verify this, since
1751 we're not caring for replacing all dups simultaneously. */
1752 if (! validate_replace_rtx (*loc, y, insn))
1755 /* Careful! First try to recognize a direct move of the
1756 value, mimicking how things are done in gen_reload wrt
1757 PLUS. Consider what happens when insn is a conditional
1758 move instruction and addsi3 clobbers flags. */
1761 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1762 seq = gen_sequence ();
1765 if (recog_memoized (new_insn) < 0)
1767 /* That failed. Fall back on force_operand and hope. */
1770 force_operand (sub, y);
1771 seq = gen_sequence ();
1776 /* Don't separate setter from user. */
1777 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1778 insn = PREV_INSN (insn);
1781 emit_insn_before (seq, insn);
1789 /* If we already have a replacement, use it. Otherwise,
1790 try to fix up this address in case it is invalid. */
1792 replacement = find_fixup_replacement (replacements, var);
1793 if (replacement->new)
1795 *loc = replacement->new;
1799 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1801 /* Unless we are forcing memory to register or we changed the mode,
1802 we can leave things the way they are if the insn is valid. */
1804 INSN_CODE (insn) = -1;
1805 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1806 && recog_memoized (insn) >= 0)
1809 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1813 /* If X contains VAR, we need to unshare it here so that we update
1814 each occurrence separately. But all identical MEMs in one insn
1815 must be replaced with the same rtx because of the possibility of
1818 if (reg_mentioned_p (var, x))
1820 replacement = find_fixup_replacement (replacements, x);
1821 if (replacement->new == 0)
1822 replacement->new = copy_most_rtx (x, var);
1824 *loc = x = replacement->new;
1840 /* Note that in some cases those types of expressions are altered
1841 by optimize_bit_field, and do not survive to get here. */
1842 if (XEXP (x, 0) == var
1843 || (GET_CODE (XEXP (x, 0)) == SUBREG
1844 && SUBREG_REG (XEXP (x, 0)) == var))
1846 /* Get TEM as a valid MEM in the mode presently in the insn.
1848 We don't worry about the possibility of MATCH_DUP here; it
1849 is highly unlikely and would be tricky to handle. */
1852 if (GET_CODE (tem) == SUBREG)
1854 if (GET_MODE_BITSIZE (GET_MODE (tem))
1855 > GET_MODE_BITSIZE (GET_MODE (var)))
1857 replacement = find_fixup_replacement (replacements, var);
1858 if (replacement->new == 0)
1859 replacement->new = gen_reg_rtx (GET_MODE (var));
1860 SUBREG_REG (tem) = replacement->new;
1863 tem = fixup_memory_subreg (tem, insn, 0);
1866 tem = fixup_stack_1 (tem, insn);
1868 /* Unless we want to load from memory, get TEM into the proper mode
1869 for an extract from memory. This can only be done if the
1870 extract is at a constant position and length. */
1872 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
1873 && GET_CODE (XEXP (x, 2)) == CONST_INT
1874 && ! mode_dependent_address_p (XEXP (tem, 0))
1875 && ! MEM_VOLATILE_P (tem))
1877 enum machine_mode wanted_mode = VOIDmode;
1878 enum machine_mode is_mode = GET_MODE (tem);
1879 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
1882 if (GET_CODE (x) == ZERO_EXTRACT)
1885 = insn_data[(int) CODE_FOR_extzv].operand[1].mode;
1886 if (wanted_mode == VOIDmode)
1887 wanted_mode = word_mode;
1891 if (GET_CODE (x) == SIGN_EXTRACT)
1893 wanted_mode = insn_data[(int) CODE_FOR_extv].operand[1].mode;
1894 if (wanted_mode == VOIDmode)
1895 wanted_mode = word_mode;
1898 /* If we have a narrower mode, we can do something. */
1899 if (wanted_mode != VOIDmode
1900 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
1902 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
1903 rtx old_pos = XEXP (x, 2);
1906 /* If the bytes and bits are counted differently, we
1907 must adjust the offset. */
1908 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
1909 offset = (GET_MODE_SIZE (is_mode)
1910 - GET_MODE_SIZE (wanted_mode) - offset);
1912 pos %= GET_MODE_BITSIZE (wanted_mode);
1914 newmem = gen_rtx_MEM (wanted_mode,
1915 plus_constant (XEXP (tem, 0), offset));
1916 RTX_UNCHANGING_P (newmem) = RTX_UNCHANGING_P (tem);
1917 MEM_COPY_ATTRIBUTES (newmem, tem);
1919 /* Make the change and see if the insn remains valid. */
1920 INSN_CODE (insn) = -1;
1921 XEXP (x, 0) = newmem;
1922 XEXP (x, 2) = GEN_INT (pos);
1924 if (recog_memoized (insn) >= 0)
1927 /* Otherwise, restore old position. XEXP (x, 0) will be
1929 XEXP (x, 2) = old_pos;
1933 /* If we get here, the bitfield extract insn can't accept a memory
1934 reference. Copy the input into a register. */
1936 tem1 = gen_reg_rtx (GET_MODE (tem));
1937 emit_insn_before (gen_move_insn (tem1, tem), insn);
1944 if (SUBREG_REG (x) == var)
1946 /* If this is a special SUBREG made because VAR was promoted
1947 from a wider mode, replace it with VAR and call ourself
1948 recursively, this time saying that the object previously
1949 had its current mode (by virtue of the SUBREG). */
1951 if (SUBREG_PROMOTED_VAR_P (x))
1954 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements);
1958 /* If this SUBREG makes VAR wider, it has become a paradoxical
1959 SUBREG with VAR in memory, but these aren't allowed at this
1960 stage of the compilation. So load VAR into a pseudo and take
1961 a SUBREG of that pseudo. */
1962 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
1964 replacement = find_fixup_replacement (replacements, var);
1965 if (replacement->new == 0)
1966 replacement->new = gen_reg_rtx (GET_MODE (var));
1967 SUBREG_REG (x) = replacement->new;
1971 /* See if we have already found a replacement for this SUBREG.
1972 If so, use it. Otherwise, make a MEM and see if the insn
1973 is recognized. If not, or if we should force MEM into a register,
1974 make a pseudo for this SUBREG. */
1975 replacement = find_fixup_replacement (replacements, x);
1976 if (replacement->new)
1978 *loc = replacement->new;
1982 replacement->new = *loc = fixup_memory_subreg (x, insn, 0);
1984 INSN_CODE (insn) = -1;
1985 if (! flag_force_mem && recog_memoized (insn) >= 0)
1988 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
1994 /* First do special simplification of bit-field references. */
1995 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
1996 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
1997 optimize_bit_field (x, insn, 0);
1998 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
1999 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2000 optimize_bit_field (x, insn, NULL_PTR);
2002 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2003 into a register and then store it back out. */
2004 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2005 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2006 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2007 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2008 > GET_MODE_SIZE (GET_MODE (var))))
2010 replacement = find_fixup_replacement (replacements, var);
2011 if (replacement->new == 0)
2012 replacement->new = gen_reg_rtx (GET_MODE (var));
2014 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2015 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2018 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2019 insn into a pseudo and store the low part of the pseudo into VAR. */
2020 if (GET_CODE (SET_DEST (x)) == SUBREG
2021 && SUBREG_REG (SET_DEST (x)) == var
2022 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2023 > GET_MODE_SIZE (GET_MODE (var))))
2025 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2026 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2033 rtx dest = SET_DEST (x);
2034 rtx src = SET_SRC (x);
2036 rtx outerdest = dest;
2039 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2040 || GET_CODE (dest) == SIGN_EXTRACT
2041 || GET_CODE (dest) == ZERO_EXTRACT)
2042 dest = XEXP (dest, 0);
2044 if (GET_CODE (src) == SUBREG)
2045 src = XEXP (src, 0);
2047 /* If VAR does not appear at the top level of the SET
2048 just scan the lower levels of the tree. */
2050 if (src != var && dest != var)
2053 /* We will need to rerecognize this insn. */
2054 INSN_CODE (insn) = -1;
2057 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var)
2059 /* Since this case will return, ensure we fixup all the
2061 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2062 insn, replacements);
2063 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2064 insn, replacements);
2065 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2066 insn, replacements);
2068 tem = XEXP (outerdest, 0);
2070 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2071 that may appear inside a ZERO_EXTRACT.
2072 This was legitimate when the MEM was a REG. */
2073 if (GET_CODE (tem) == SUBREG
2074 && SUBREG_REG (tem) == var)
2075 tem = fixup_memory_subreg (tem, insn, 0);
2077 tem = fixup_stack_1 (tem, insn);
2079 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2080 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2081 && ! mode_dependent_address_p (XEXP (tem, 0))
2082 && ! MEM_VOLATILE_P (tem))
2084 enum machine_mode wanted_mode;
2085 enum machine_mode is_mode = GET_MODE (tem);
2086 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2088 wanted_mode = insn_data[(int) CODE_FOR_insv].operand[0].mode;
2089 if (wanted_mode == VOIDmode)
2090 wanted_mode = word_mode;
2092 /* If we have a narrower mode, we can do something. */
2093 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2095 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2096 rtx old_pos = XEXP (outerdest, 2);
2099 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2100 offset = (GET_MODE_SIZE (is_mode)
2101 - GET_MODE_SIZE (wanted_mode) - offset);
2103 pos %= GET_MODE_BITSIZE (wanted_mode);
2105 newmem = gen_rtx_MEM (wanted_mode,
2106 plus_constant (XEXP (tem, 0),
2108 RTX_UNCHANGING_P (newmem) = RTX_UNCHANGING_P (tem);
2109 MEM_COPY_ATTRIBUTES (newmem, tem);
2111 /* Make the change and see if the insn remains valid. */
2112 INSN_CODE (insn) = -1;
2113 XEXP (outerdest, 0) = newmem;
2114 XEXP (outerdest, 2) = GEN_INT (pos);
2116 if (recog_memoized (insn) >= 0)
2119 /* Otherwise, restore old position. XEXP (x, 0) will be
2121 XEXP (outerdest, 2) = old_pos;
2125 /* If we get here, the bit-field store doesn't allow memory
2126 or isn't located at a constant position. Load the value into
2127 a register, do the store, and put it back into memory. */
2129 tem1 = gen_reg_rtx (GET_MODE (tem));
2130 emit_insn_before (gen_move_insn (tem1, tem), insn);
2131 emit_insn_after (gen_move_insn (tem, tem1), insn);
2132 XEXP (outerdest, 0) = tem1;
2137 /* STRICT_LOW_PART is a no-op on memory references
2138 and it can cause combinations to be unrecognizable,
2141 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2142 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2144 /* A valid insn to copy VAR into or out of a register
2145 must be left alone, to avoid an infinite loop here.
2146 If the reference to VAR is by a subreg, fix that up,
2147 since SUBREG is not valid for a memref.
2148 Also fix up the address of the stack slot.
2150 Note that we must not try to recognize the insn until
2151 after we know that we have valid addresses and no
2152 (subreg (mem ...) ...) constructs, since these interfere
2153 with determining the validity of the insn. */
2155 if ((SET_SRC (x) == var
2156 || (GET_CODE (SET_SRC (x)) == SUBREG
2157 && SUBREG_REG (SET_SRC (x)) == var))
2158 && (GET_CODE (SET_DEST (x)) == REG
2159 || (GET_CODE (SET_DEST (x)) == SUBREG
2160 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2161 && GET_MODE (var) == promoted_mode
2162 && x == single_set (insn))
2166 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2167 if (replacement->new)
2168 SET_SRC (x) = replacement->new;
2169 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2170 SET_SRC (x) = replacement->new
2171 = fixup_memory_subreg (SET_SRC (x), insn, 0);
2173 SET_SRC (x) = replacement->new
2174 = fixup_stack_1 (SET_SRC (x), insn);
2176 if (recog_memoized (insn) >= 0)
2179 /* INSN is not valid, but we know that we want to
2180 copy SET_SRC (x) to SET_DEST (x) in some way. So
2181 we generate the move and see whether it requires more
2182 than one insn. If it does, we emit those insns and
2183 delete INSN. Otherwise, we an just replace the pattern
2184 of INSN; we have already verified above that INSN has
2185 no other function that to do X. */
2187 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2188 if (GET_CODE (pat) == SEQUENCE)
2190 emit_insn_after (pat, insn);
2191 PUT_CODE (insn, NOTE);
2192 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
2193 NOTE_SOURCE_FILE (insn) = 0;
2196 PATTERN (insn) = pat;
2201 if ((SET_DEST (x) == var
2202 || (GET_CODE (SET_DEST (x)) == SUBREG
2203 && SUBREG_REG (SET_DEST (x)) == var))
2204 && (GET_CODE (SET_SRC (x)) == REG
2205 || (GET_CODE (SET_SRC (x)) == SUBREG
2206 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2207 && GET_MODE (var) == promoted_mode
2208 && x == single_set (insn))
2212 if (GET_CODE (SET_DEST (x)) == SUBREG)
2213 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn, 0);
2215 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2217 if (recog_memoized (insn) >= 0)
2220 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2221 if (GET_CODE (pat) == SEQUENCE)
2223 emit_insn_after (pat, insn);
2224 PUT_CODE (insn, NOTE);
2225 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
2226 NOTE_SOURCE_FILE (insn) = 0;
2229 PATTERN (insn) = pat;
2234 /* Otherwise, storing into VAR must be handled specially
2235 by storing into a temporary and copying that into VAR
2236 with a new insn after this one. Note that this case
2237 will be used when storing into a promoted scalar since
2238 the insn will now have different modes on the input
2239 and output and hence will be invalid (except for the case
2240 of setting it to a constant, which does not need any
2241 change if it is valid). We generate extra code in that case,
2242 but combine.c will eliminate it. */
2247 rtx fixeddest = SET_DEST (x);
2249 /* STRICT_LOW_PART can be discarded, around a MEM. */
2250 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2251 fixeddest = XEXP (fixeddest, 0);
2252 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2253 if (GET_CODE (fixeddest) == SUBREG)
2255 fixeddest = fixup_memory_subreg (fixeddest, insn, 0);
2256 promoted_mode = GET_MODE (fixeddest);
2259 fixeddest = fixup_stack_1 (fixeddest, insn);
2261 temp = gen_reg_rtx (promoted_mode);
2263 emit_insn_after (gen_move_insn (fixeddest,
2264 gen_lowpart (GET_MODE (fixeddest),
2268 SET_DEST (x) = temp;
2276 /* Nothing special about this RTX; fix its operands. */
2278 fmt = GET_RTX_FORMAT (code);
2279 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2282 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements);
2286 for (j = 0; j < XVECLEN (x, i); j++)
2287 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2288 insn, replacements);
2293 /* Given X, an rtx of the form (SUBREG:m1 (MEM:m2 addr)),
2294 return an rtx (MEM:m1 newaddr) which is equivalent.
2295 If any insns must be emitted to compute NEWADDR, put them before INSN.
2297 UNCRITICAL nonzero means accept paradoxical subregs.
2298 This is used for subregs found inside REG_NOTES. */
2301 fixup_memory_subreg (x, insn, uncritical)
2306 int offset = SUBREG_WORD (x) * UNITS_PER_WORD;
2307 rtx addr = XEXP (SUBREG_REG (x), 0);
2308 enum machine_mode mode = GET_MODE (x);
2311 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2312 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))
2316 if (BYTES_BIG_ENDIAN)
2317 offset += (MIN (UNITS_PER_WORD, GET_MODE_SIZE (GET_MODE (SUBREG_REG (x))))
2318 - MIN (UNITS_PER_WORD, GET_MODE_SIZE (mode)));
2319 addr = plus_constant (addr, offset);
2320 if (!flag_force_addr && memory_address_p (mode, addr))
2321 /* Shortcut if no insns need be emitted. */
2322 return change_address (SUBREG_REG (x), mode, addr);
2324 result = change_address (SUBREG_REG (x), mode, addr);
2325 emit_insn_before (gen_sequence (), insn);
2330 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2331 Replace subexpressions of X in place.
2332 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2333 Otherwise return X, with its contents possibly altered.
2335 If any insns must be emitted to compute NEWADDR, put them before INSN.
2337 UNCRITICAL is as in fixup_memory_subreg. */
2340 walk_fixup_memory_subreg (x, insn, uncritical)
2345 register enum rtx_code code;
2346 register const char *fmt;
2352 code = GET_CODE (x);
2354 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2355 return fixup_memory_subreg (x, insn, uncritical);
2357 /* Nothing special about this RTX; fix its operands. */
2359 fmt = GET_RTX_FORMAT (code);
2360 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2363 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn, uncritical);
2367 for (j = 0; j < XVECLEN (x, i); j++)
2369 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn, uncritical);
2375 /* For each memory ref within X, if it refers to a stack slot
2376 with an out of range displacement, put the address in a temp register
2377 (emitting new insns before INSN to load these registers)
2378 and alter the memory ref to use that register.
2379 Replace each such MEM rtx with a copy, to avoid clobberage. */
2382 fixup_stack_1 (x, insn)
2387 register RTX_CODE code = GET_CODE (x);
2388 register const char *fmt;
2392 register rtx ad = XEXP (x, 0);
2393 /* If we have address of a stack slot but it's not valid
2394 (displacement is too large), compute the sum in a register. */
2395 if (GET_CODE (ad) == PLUS
2396 && GET_CODE (XEXP (ad, 0)) == REG
2397 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2398 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2399 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2400 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2401 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2403 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2404 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2405 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2406 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2409 if (memory_address_p (GET_MODE (x), ad))
2413 temp = copy_to_reg (ad);
2414 seq = gen_sequence ();
2416 emit_insn_before (seq, insn);
2417 return change_address (x, VOIDmode, temp);
2422 fmt = GET_RTX_FORMAT (code);
2423 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2426 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2430 for (j = 0; j < XVECLEN (x, i); j++)
2431 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2437 /* Optimization: a bit-field instruction whose field
2438 happens to be a byte or halfword in memory
2439 can be changed to a move instruction.
2441 We call here when INSN is an insn to examine or store into a bit-field.
2442 BODY is the SET-rtx to be altered.
2444 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2445 (Currently this is called only from function.c, and EQUIV_MEM
2449 optimize_bit_field (body, insn, equiv_mem)
2454 register rtx bitfield;
2457 enum machine_mode mode;
2459 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2460 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2461 bitfield = SET_DEST (body), destflag = 1;
2463 bitfield = SET_SRC (body), destflag = 0;
2465 /* First check that the field being stored has constant size and position
2466 and is in fact a byte or halfword suitably aligned. */
2468 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2469 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2470 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2472 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2474 register rtx memref = 0;
2476 /* Now check that the containing word is memory, not a register,
2477 and that it is safe to change the machine mode. */
2479 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2480 memref = XEXP (bitfield, 0);
2481 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2483 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2484 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2485 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2486 memref = SUBREG_REG (XEXP (bitfield, 0));
2487 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2489 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2490 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2493 && ! mode_dependent_address_p (XEXP (memref, 0))
2494 && ! MEM_VOLATILE_P (memref))
2496 /* Now adjust the address, first for any subreg'ing
2497 that we are now getting rid of,
2498 and then for which byte of the word is wanted. */
2500 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2503 /* Adjust OFFSET to count bits from low-address byte. */
2504 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2505 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2506 - offset - INTVAL (XEXP (bitfield, 1)));
2508 /* Adjust OFFSET to count bytes from low-address byte. */
2509 offset /= BITS_PER_UNIT;
2510 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2512 offset += SUBREG_WORD (XEXP (bitfield, 0)) * UNITS_PER_WORD;
2513 if (BYTES_BIG_ENDIAN)
2514 offset -= (MIN (UNITS_PER_WORD,
2515 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2516 - MIN (UNITS_PER_WORD,
2517 GET_MODE_SIZE (GET_MODE (memref))));
2521 memref = change_address (memref, mode,
2522 plus_constant (XEXP (memref, 0), offset));
2523 insns = get_insns ();
2525 emit_insns_before (insns, insn);
2527 /* Store this memory reference where
2528 we found the bit field reference. */
2532 validate_change (insn, &SET_DEST (body), memref, 1);
2533 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2535 rtx src = SET_SRC (body);
2536 while (GET_CODE (src) == SUBREG
2537 && SUBREG_WORD (src) == 0)
2538 src = SUBREG_REG (src);
2539 if (GET_MODE (src) != GET_MODE (memref))
2540 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2541 validate_change (insn, &SET_SRC (body), src, 1);
2543 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2544 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2545 /* This shouldn't happen because anything that didn't have
2546 one of these modes should have got converted explicitly
2547 and then referenced through a subreg.
2548 This is so because the original bit-field was
2549 handled by agg_mode and so its tree structure had
2550 the same mode that memref now has. */
2555 rtx dest = SET_DEST (body);
2557 while (GET_CODE (dest) == SUBREG
2558 && SUBREG_WORD (dest) == 0
2559 && (GET_MODE_CLASS (GET_MODE (dest))
2560 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2561 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2563 dest = SUBREG_REG (dest);
2565 validate_change (insn, &SET_DEST (body), dest, 1);
2567 if (GET_MODE (dest) == GET_MODE (memref))
2568 validate_change (insn, &SET_SRC (body), memref, 1);
2571 /* Convert the mem ref to the destination mode. */
2572 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2575 convert_move (newreg, memref,
2576 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2580 validate_change (insn, &SET_SRC (body), newreg, 1);
2584 /* See if we can convert this extraction or insertion into
2585 a simple move insn. We might not be able to do so if this
2586 was, for example, part of a PARALLEL.
2588 If we succeed, write out any needed conversions. If we fail,
2589 it is hard to guess why we failed, so don't do anything
2590 special; just let the optimization be suppressed. */
2592 if (apply_change_group () && seq)
2593 emit_insns_before (seq, insn);
2598 /* These routines are responsible for converting virtual register references
2599 to the actual hard register references once RTL generation is complete.
2601 The following four variables are used for communication between the
2602 routines. They contain the offsets of the virtual registers from their
2603 respective hard registers. */
2605 static int in_arg_offset;
2606 static int var_offset;
2607 static int dynamic_offset;
2608 static int out_arg_offset;
2609 static int cfa_offset;
2611 /* In most machines, the stack pointer register is equivalent to the bottom
2614 #ifndef STACK_POINTER_OFFSET
2615 #define STACK_POINTER_OFFSET 0
2618 /* If not defined, pick an appropriate default for the offset of dynamically
2619 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2620 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2622 #ifndef STACK_DYNAMIC_OFFSET
2624 #ifdef ACCUMULATE_OUTGOING_ARGS
2625 /* The bottom of the stack points to the actual arguments. If
2626 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2627 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2628 stack space for register parameters is not pushed by the caller, but
2629 rather part of the fixed stack areas and hence not included in
2630 `current_function_outgoing_args_size'. Nevertheless, we must allow
2631 for it when allocating stack dynamic objects. */
2633 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2634 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2635 (current_function_outgoing_args_size \
2636 + REG_PARM_STACK_SPACE (FNDECL) + (STACK_POINTER_OFFSET))
2639 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2640 (current_function_outgoing_args_size + (STACK_POINTER_OFFSET))
2644 #define STACK_DYNAMIC_OFFSET(FNDECL) STACK_POINTER_OFFSET
2648 /* On a few machines, the CFA coincides with the arg pointer. */
2650 #ifndef ARG_POINTER_CFA_OFFSET
2651 #define ARG_POINTER_CFA_OFFSET 0
2655 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just had
2656 its address taken. DECL is the decl for the object stored in the
2657 register, for later use if we do need to force REG into the stack.
2658 REG is overwritten by the MEM like in put_reg_into_stack. */
2661 gen_mem_addressof (reg, decl)
2665 tree type = TREE_TYPE (decl);
2666 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2668 /* If the original REG was a user-variable, then so is the REG whose
2669 address is being taken. */
2670 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2672 PUT_CODE (reg, MEM);
2673 PUT_MODE (reg, DECL_MODE (decl));
2675 MEM_VOLATILE_P (reg) = TREE_SIDE_EFFECTS (decl);
2676 MEM_SET_IN_STRUCT_P (reg, AGGREGATE_TYPE_P (type));
2677 MEM_ALIAS_SET (reg) = get_alias_set (decl);
2679 if (TREE_USED (decl) || DECL_INITIAL (decl) != 0)
2680 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), 0);
2685 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2689 flush_addressof (decl)
2692 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2693 && DECL_RTL (decl) != 0
2694 && GET_CODE (DECL_RTL (decl)) == MEM
2695 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2696 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2697 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2701 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2704 put_addressof_into_stack (r, ht)
2706 struct hash_table *ht;
2708 tree decl = ADDRESSOF_DECL (r);
2709 rtx reg = XEXP (r, 0);
2711 if (GET_CODE (reg) != REG)
2714 put_reg_into_stack (0, reg, TREE_TYPE (decl), GET_MODE (reg),
2715 DECL_MODE (decl), TREE_SIDE_EFFECTS (decl),
2716 ADDRESSOF_REGNO (r),
2717 TREE_USED (decl) || DECL_INITIAL (decl) != 0, ht);
2720 /* List of replacements made below in purge_addressof_1 when creating
2721 bitfield insertions. */
2722 static rtx purge_bitfield_addressof_replacements;
2724 /* List of replacements made below in purge_addressof_1 for patterns
2725 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2726 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2727 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2728 enough in complex cases, e.g. when some field values can be
2729 extracted by usage MEM with narrower mode. */
2730 static rtx purge_addressof_replacements;
2732 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2733 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2737 purge_addressof_1 (loc, insn, force, store, ht)
2741 struct hash_table *ht;
2748 /* Re-start here to avoid recursion in common cases. */
2755 code = GET_CODE (x);
2757 /* If we don't return in any of the cases below, we will recurse inside
2758 the RTX, which will normally result in any ADDRESSOF being forced into
2762 purge_addressof_1 (&SET_DEST (x), insn, force, 1, ht);
2763 purge_addressof_1 (&SET_SRC (x), insn, force, 0, ht);
2767 else if (code == ADDRESSOF && GET_CODE (XEXP (x, 0)) == MEM)
2769 /* We must create a copy of the rtx because it was created by
2770 overwriting a REG rtx which is always shared. */
2771 rtx sub = copy_rtx (XEXP (XEXP (x, 0), 0));
2774 if (validate_change (insn, loc, sub, 0)
2775 || validate_replace_rtx (x, sub, insn))
2779 sub = force_operand (sub, NULL_RTX);
2780 if (! validate_change (insn, loc, sub, 0)
2781 && ! validate_replace_rtx (x, sub, insn))
2784 insns = gen_sequence ();
2786 emit_insn_before (insns, insn);
2790 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
2792 rtx sub = XEXP (XEXP (x, 0), 0);
2795 if (GET_CODE (sub) == MEM)
2797 sub2 = gen_rtx_MEM (GET_MODE (x), copy_rtx (XEXP (sub, 0)));
2798 MEM_COPY_ATTRIBUTES (sub2, sub);
2799 RTX_UNCHANGING_P (sub2) = RTX_UNCHANGING_P (sub);
2802 else if (GET_CODE (sub) == REG
2803 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
2805 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
2807 int size_x, size_sub;
2811 /* When processing REG_NOTES look at the list of
2812 replacements done on the insn to find the register that X
2816 for (tem = purge_bitfield_addressof_replacements;
2818 tem = XEXP (XEXP (tem, 1), 1))
2819 if (rtx_equal_p (x, XEXP (tem, 0)))
2821 *loc = XEXP (XEXP (tem, 1), 0);
2825 /* See comment for purge_addressof_replacements. */
2826 for (tem = purge_addressof_replacements;
2828 tem = XEXP (XEXP (tem, 1), 1))
2829 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
2831 rtx z = XEXP (XEXP (tem, 1), 0);
2833 if (GET_MODE (x) == GET_MODE (z)
2834 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
2835 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
2838 /* It can happen that the note may speak of things
2839 in a wider (or just different) mode than the
2840 code did. This is especially true of
2843 if (GET_CODE (z) == SUBREG && SUBREG_WORD (z) == 0)
2846 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
2847 && (GET_MODE_SIZE (GET_MODE (x))
2848 > GET_MODE_SIZE (GET_MODE (z))))
2850 /* This can occur as a result in invalid
2851 pointer casts, e.g. float f; ...
2852 *(long long int *)&f.
2853 ??? We could emit a warning here, but
2854 without a line number that wouldn't be
2856 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
2859 z = gen_lowpart (GET_MODE (x), z);
2865 /* There should always be such a replacement. */
2869 size_x = GET_MODE_BITSIZE (GET_MODE (x));
2870 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
2872 /* Don't even consider working with paradoxical subregs,
2873 or the moral equivalent seen here. */
2874 if (size_x <= size_sub
2875 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
2877 /* Do a bitfield insertion to mirror what would happen
2884 rtx p = PREV_INSN (insn);
2887 val = gen_reg_rtx (GET_MODE (x));
2888 if (! validate_change (insn, loc, val, 0))
2890 /* Discard the current sequence and put the
2891 ADDRESSOF on stack. */
2895 seq = gen_sequence ();
2897 emit_insn_before (seq, insn);
2898 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
2902 store_bit_field (sub, size_x, 0, GET_MODE (x),
2903 val, GET_MODE_SIZE (GET_MODE (sub)),
2904 GET_MODE_SIZE (GET_MODE (sub)));
2906 /* Make sure to unshare any shared rtl that store_bit_field
2907 might have created. */
2908 for (p = get_insns(); p; p = NEXT_INSN (p))
2910 reset_used_flags (PATTERN (p));
2911 reset_used_flags (REG_NOTES (p));
2912 reset_used_flags (LOG_LINKS (p));
2914 unshare_all_rtl (get_insns ());
2916 seq = gen_sequence ();
2918 p = emit_insn_after (seq, insn);
2919 if (NEXT_INSN (insn))
2920 compute_insns_for_mem (NEXT_INSN (insn),
2921 p ? NEXT_INSN (p) : NULL_RTX,
2926 rtx p = PREV_INSN (insn);
2929 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
2930 GET_MODE (x), GET_MODE (x),
2931 GET_MODE_SIZE (GET_MODE (sub)),
2932 GET_MODE_SIZE (GET_MODE (sub)));
2934 if (! validate_change (insn, loc, val, 0))
2936 /* Discard the current sequence and put the
2937 ADDRESSOF on stack. */
2942 seq = gen_sequence ();
2944 emit_insn_before (seq, insn);
2945 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
2949 /* Remember the replacement so that the same one can be done
2950 on the REG_NOTES. */
2951 purge_bitfield_addressof_replacements
2952 = gen_rtx_EXPR_LIST (VOIDmode, x,
2955 purge_bitfield_addressof_replacements));
2957 /* We replaced with a reg -- all done. */
2962 else if (validate_change (insn, loc, sub, 0))
2964 /* Remember the replacement so that the same one can be done
2965 on the REG_NOTES. */
2966 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
2970 for (tem = purge_addressof_replacements;
2972 tem = XEXP (XEXP (tem, 1), 1))
2973 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
2975 XEXP (XEXP (tem, 1), 0) = sub;
2978 purge_addressof_replacements
2979 = gen_rtx (EXPR_LIST, VOIDmode, XEXP (x, 0),
2980 gen_rtx_EXPR_LIST (VOIDmode, sub,
2981 purge_addressof_replacements));
2987 /* else give up and put it into the stack */
2990 else if (code == ADDRESSOF)
2992 put_addressof_into_stack (x, ht);
2995 else if (code == SET)
2997 purge_addressof_1 (&SET_DEST (x), insn, force, 1, ht);
2998 purge_addressof_1 (&SET_SRC (x), insn, force, 0, ht);
3002 /* Scan all subexpressions. */
3003 fmt = GET_RTX_FORMAT (code);
3004 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3007 purge_addressof_1 (&XEXP (x, i), insn, force, 0, ht);
3008 else if (*fmt == 'E')
3009 for (j = 0; j < XVECLEN (x, i); j++)
3010 purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0, ht);
3014 /* Return a new hash table entry in HT. */
3016 static struct hash_entry *
3017 insns_for_mem_newfunc (he, ht, k)
3018 struct hash_entry *he;
3019 struct hash_table *ht;
3020 hash_table_key k ATTRIBUTE_UNUSED;
3022 struct insns_for_mem_entry *ifmhe;
3026 ifmhe = ((struct insns_for_mem_entry *)
3027 hash_allocate (ht, sizeof (struct insns_for_mem_entry)));
3028 ifmhe->insns = NULL_RTX;
3033 /* Return a hash value for K, a REG. */
3035 static unsigned long
3036 insns_for_mem_hash (k)
3039 /* K is really a RTX. Just use the address as the hash value. */
3040 return (unsigned long) k;
3043 /* Return non-zero if K1 and K2 (two REGs) are the same. */
3046 insns_for_mem_comp (k1, k2)
3053 struct insns_for_mem_walk_info {
3054 /* The hash table that we are using to record which INSNs use which
3056 struct hash_table *ht;
3058 /* The INSN we are currently proessing. */
3061 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3062 to find the insns that use the REGs in the ADDRESSOFs. */
3066 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3067 that might be used in an ADDRESSOF expression, record this INSN in
3068 the hash table given by DATA (which is really a pointer to an
3069 insns_for_mem_walk_info structure). */
3072 insns_for_mem_walk (r, data)
3076 struct insns_for_mem_walk_info *ifmwi
3077 = (struct insns_for_mem_walk_info *) data;
3079 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3080 && GET_CODE (XEXP (*r, 0)) == REG)
3081 hash_lookup (ifmwi->ht, XEXP (*r, 0), /*create=*/1, /*copy=*/0);
3082 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3084 /* Lookup this MEM in the hashtable, creating it if necessary. */
3085 struct insns_for_mem_entry *ifme
3086 = (struct insns_for_mem_entry *) hash_lookup (ifmwi->ht,
3091 /* If we have not already recorded this INSN, do so now. Since
3092 we process the INSNs in order, we know that if we have
3093 recorded it it must be at the front of the list. */
3094 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3096 /* We do the allocation on the same obstack as is used for
3097 the hash table since this memory will not be used once
3098 the hash table is deallocated. */
3099 push_obstacks (&ifmwi->ht->memory, &ifmwi->ht->memory);
3100 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3109 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3110 which REGs in HT. */
3113 compute_insns_for_mem (insns, last_insn, ht)
3116 struct hash_table *ht;
3119 struct insns_for_mem_walk_info ifmwi;
3122 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3123 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3124 if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
3127 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3131 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3132 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3136 purge_addressof (insns)
3140 struct hash_table ht;
3142 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3143 requires a fixup pass over the instruction stream to correct
3144 INSNs that depended on the REG being a REG, and not a MEM. But,
3145 these fixup passes are slow. Furthermore, more MEMs are not
3146 mentioned in very many instructions. So, we speed up the process
3147 by pre-calculating which REGs occur in which INSNs; that allows
3148 us to perform the fixup passes much more quickly. */
3149 hash_table_init (&ht,
3150 insns_for_mem_newfunc,
3152 insns_for_mem_comp);
3153 compute_insns_for_mem (insns, NULL_RTX, &ht);
3155 for (insn = insns; insn; insn = NEXT_INSN (insn))
3156 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3157 || GET_CODE (insn) == CALL_INSN)
3159 purge_addressof_1 (&PATTERN (insn), insn,
3160 asm_noperands (PATTERN (insn)) > 0, 0, &ht);
3161 purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, &ht);
3165 hash_table_free (&ht);
3166 purge_bitfield_addressof_replacements = 0;
3167 purge_addressof_replacements = 0;
3170 /* Pass through the INSNS of function FNDECL and convert virtual register
3171 references to hard register references. */
3174 instantiate_virtual_regs (fndecl, insns)
3181 /* Compute the offsets to use for this function. */
3182 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3183 var_offset = STARTING_FRAME_OFFSET;
3184 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3185 out_arg_offset = STACK_POINTER_OFFSET;
3186 cfa_offset = ARG_POINTER_CFA_OFFSET;
3188 /* Scan all variables and parameters of this function. For each that is
3189 in memory, instantiate all virtual registers if the result is a valid
3190 address. If not, we do it later. That will handle most uses of virtual
3191 regs on many machines. */
3192 instantiate_decls (fndecl, 1);
3194 /* Initialize recognition, indicating that volatile is OK. */
3197 /* Scan through all the insns, instantiating every virtual register still
3199 for (insn = insns; insn; insn = NEXT_INSN (insn))
3200 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3201 || GET_CODE (insn) == CALL_INSN)
3203 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3204 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3207 /* Instantiate the stack slots for the parm registers, for later use in
3208 addressof elimination. */
3209 for (i = 0; i < max_parm_reg; ++i)
3210 if (parm_reg_stack_loc[i])
3211 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3213 /* Now instantiate the remaining register equivalences for debugging info.
3214 These will not be valid addresses. */
3215 instantiate_decls (fndecl, 0);
3217 /* Indicate that, from now on, assign_stack_local should use
3218 frame_pointer_rtx. */
3219 virtuals_instantiated = 1;
3222 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3223 all virtual registers in their DECL_RTL's.
3225 If VALID_ONLY, do this only if the resulting address is still valid.
3226 Otherwise, always do it. */
3229 instantiate_decls (fndecl, valid_only)
3235 if (DECL_SAVED_INSNS (fndecl))
3236 /* When compiling an inline function, the obstack used for
3237 rtl allocation is the maybepermanent_obstack. Calling
3238 `resume_temporary_allocation' switches us back to that
3239 obstack while we process this function's parameters. */
3240 resume_temporary_allocation ();
3242 /* Process all parameters of the function. */
3243 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3245 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3247 instantiate_decl (DECL_RTL (decl), size, valid_only);
3249 /* If the parameter was promoted, then the incoming RTL mode may be
3250 larger than the declared type size. We must use the larger of
3252 size = MAX (GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl))), size);
3253 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3256 /* Now process all variables defined in the function or its subblocks. */
3257 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3259 if (DECL_INLINE (fndecl) || DECL_DEFER_OUTPUT (fndecl))
3261 /* Save all rtl allocated for this function by raising the
3262 high-water mark on the maybepermanent_obstack. */
3264 /* All further rtl allocation is now done in the current_obstack. */
3265 rtl_in_current_obstack ();
3269 /* Subroutine of instantiate_decls: Process all decls in the given
3270 BLOCK node and all its subblocks. */
3273 instantiate_decls_1 (let, valid_only)
3279 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3280 instantiate_decl (DECL_RTL (t), int_size_in_bytes (TREE_TYPE (t)),
3283 /* Process all subblocks. */
3284 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3285 instantiate_decls_1 (t, valid_only);
3288 /* Subroutine of the preceding procedures: Given RTL representing a
3289 decl and the size of the object, do any instantiation required.
3291 If VALID_ONLY is non-zero, it means that the RTL should only be
3292 changed if the new address is valid. */
3295 instantiate_decl (x, size, valid_only)
3300 enum machine_mode mode;
3303 /* If this is not a MEM, no need to do anything. Similarly if the
3304 address is a constant or a register that is not a virtual register. */
3306 if (x == 0 || GET_CODE (x) != MEM)
3310 if (CONSTANT_P (addr)
3311 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3312 || (GET_CODE (addr) == REG
3313 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3314 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3317 /* If we should only do this if the address is valid, copy the address.
3318 We need to do this so we can undo any changes that might make the
3319 address invalid. This copy is unfortunate, but probably can't be
3323 addr = copy_rtx (addr);
3325 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3329 /* Now verify that the resulting address is valid for every integer or
3330 floating-point mode up to and including SIZE bytes long. We do this
3331 since the object might be accessed in any mode and frame addresses
3334 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3335 mode != VOIDmode && GET_MODE_SIZE (mode) <= size;
3336 mode = GET_MODE_WIDER_MODE (mode))
3337 if (! memory_address_p (mode, addr))
3340 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3341 mode != VOIDmode && GET_MODE_SIZE (mode) <= size;
3342 mode = GET_MODE_WIDER_MODE (mode))
3343 if (! memory_address_p (mode, addr))
3347 /* Put back the address now that we have updated it and we either know
3348 it is valid or we don't care whether it is valid. */
3353 /* Given a pointer to a piece of rtx and an optional pointer to the
3354 containing object, instantiate any virtual registers present in it.
3356 If EXTRA_INSNS, we always do the replacement and generate
3357 any extra insns before OBJECT. If it zero, we do nothing if replacement
3360 Return 1 if we either had nothing to do or if we were able to do the
3361 needed replacement. Return 0 otherwise; we only return zero if
3362 EXTRA_INSNS is zero.
3364 We first try some simple transformations to avoid the creation of extra
3368 instantiate_virtual_regs_1 (loc, object, extra_insns)
3376 HOST_WIDE_INT offset = 0;
3382 /* Re-start here to avoid recursion in common cases. */
3389 code = GET_CODE (x);
3391 /* Check for some special cases. */
3408 /* We are allowed to set the virtual registers. This means that
3409 the actual register should receive the source minus the
3410 appropriate offset. This is used, for example, in the handling
3411 of non-local gotos. */
3412 if (SET_DEST (x) == virtual_incoming_args_rtx)
3413 new = arg_pointer_rtx, offset = - in_arg_offset;
3414 else if (SET_DEST (x) == virtual_stack_vars_rtx)
3415 new = frame_pointer_rtx, offset = - var_offset;
3416 else if (SET_DEST (x) == virtual_stack_dynamic_rtx)
3417 new = stack_pointer_rtx, offset = - dynamic_offset;
3418 else if (SET_DEST (x) == virtual_outgoing_args_rtx)
3419 new = stack_pointer_rtx, offset = - out_arg_offset;
3420 else if (SET_DEST (x) == virtual_cfa_rtx)
3421 new = arg_pointer_rtx, offset = - cfa_offset;
3425 /* The only valid sources here are PLUS or REG. Just do
3426 the simplest possible thing to handle them. */
3427 if (GET_CODE (SET_SRC (x)) != REG
3428 && GET_CODE (SET_SRC (x)) != PLUS)
3432 if (GET_CODE (SET_SRC (x)) != REG)
3433 temp = force_operand (SET_SRC (x), NULL_RTX);
3436 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3440 emit_insns_before (seq, object);
3443 if (! validate_change (object, &SET_SRC (x), temp, 0)
3450 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3455 /* Handle special case of virtual register plus constant. */
3456 if (CONSTANT_P (XEXP (x, 1)))
3458 rtx old, new_offset;
3460 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3461 if (GET_CODE (XEXP (x, 0)) == PLUS)
3463 rtx inner = XEXP (XEXP (x, 0), 0);
3465 if (inner == virtual_incoming_args_rtx)
3466 new = arg_pointer_rtx, offset = in_arg_offset;
3467 else if (inner == virtual_stack_vars_rtx)
3468 new = frame_pointer_rtx, offset = var_offset;
3469 else if (inner == virtual_stack_dynamic_rtx)
3470 new = stack_pointer_rtx, offset = dynamic_offset;
3471 else if (inner == virtual_outgoing_args_rtx)
3472 new = stack_pointer_rtx, offset = out_arg_offset;
3473 else if (inner == virtual_cfa_rtx)
3474 new = arg_pointer_rtx, offset = cfa_offset;
3481 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3483 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3486 else if (XEXP (x, 0) == virtual_incoming_args_rtx)
3487 new = arg_pointer_rtx, offset = in_arg_offset;
3488 else if (XEXP (x, 0) == virtual_stack_vars_rtx)
3489 new = frame_pointer_rtx, offset = var_offset;
3490 else if (XEXP (x, 0) == virtual_stack_dynamic_rtx)
3491 new = stack_pointer_rtx, offset = dynamic_offset;
3492 else if (XEXP (x, 0) == virtual_outgoing_args_rtx)
3493 new = stack_pointer_rtx, offset = out_arg_offset;
3494 else if (XEXP (x, 0) == virtual_cfa_rtx)
3495 new = arg_pointer_rtx, offset = cfa_offset;
3498 /* We know the second operand is a constant. Unless the
3499 first operand is a REG (which has been already checked),
3500 it needs to be checked. */
3501 if (GET_CODE (XEXP (x, 0)) != REG)
3509 new_offset = plus_constant (XEXP (x, 1), offset);
3511 /* If the new constant is zero, try to replace the sum with just
3513 if (new_offset == const0_rtx
3514 && validate_change (object, loc, new, 0))
3517 /* Next try to replace the register and new offset.
3518 There are two changes to validate here and we can't assume that
3519 in the case of old offset equals new just changing the register
3520 will yield a valid insn. In the interests of a little efficiency,
3521 however, we only call validate change once (we don't queue up the
3522 changes and then call apply_change_group). */
3526 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3527 : (XEXP (x, 0) = new,
3528 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3536 /* Otherwise copy the new constant into a register and replace
3537 constant with that register. */
3538 temp = gen_reg_rtx (Pmode);
3540 if (validate_change (object, &XEXP (x, 1), temp, 0))
3541 emit_insn_before (gen_move_insn (temp, new_offset), object);
3544 /* If that didn't work, replace this expression with a
3545 register containing the sum. */
3548 new = gen_rtx_PLUS (Pmode, new, new_offset);
3551 temp = force_operand (new, NULL_RTX);
3555 emit_insns_before (seq, object);
3556 if (! validate_change (object, loc, temp, 0)
3557 && ! validate_replace_rtx (x, temp, object))
3565 /* Fall through to generic two-operand expression case. */
3571 case DIV: case UDIV:
3572 case MOD: case UMOD:
3573 case AND: case IOR: case XOR:
3574 case ROTATERT: case ROTATE:
3575 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3577 case GE: case GT: case GEU: case GTU:
3578 case LE: case LT: case LEU: case LTU:
3579 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3580 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3585 /* Most cases of MEM that convert to valid addresses have already been
3586 handled by our scan of decls. The only special handling we
3587 need here is to make a copy of the rtx to ensure it isn't being
3588 shared if we have to change it to a pseudo.
3590 If the rtx is a simple reference to an address via a virtual register,
3591 it can potentially be shared. In such cases, first try to make it
3592 a valid address, which can also be shared. Otherwise, copy it and
3595 First check for common cases that need no processing. These are
3596 usually due to instantiation already being done on a previous instance
3600 if (CONSTANT_ADDRESS_P (temp)
3601 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3602 || temp == arg_pointer_rtx
3604 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3605 || temp == hard_frame_pointer_rtx
3607 || temp == frame_pointer_rtx)
3610 if (GET_CODE (temp) == PLUS
3611 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3612 && (XEXP (temp, 0) == frame_pointer_rtx
3613 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3614 || XEXP (temp, 0) == hard_frame_pointer_rtx
3616 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3617 || XEXP (temp, 0) == arg_pointer_rtx
3622 if (temp == virtual_stack_vars_rtx
3623 || temp == virtual_incoming_args_rtx
3624 || (GET_CODE (temp) == PLUS
3625 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3626 && (XEXP (temp, 0) == virtual_stack_vars_rtx
3627 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
3629 /* This MEM may be shared. If the substitution can be done without
3630 the need to generate new pseudos, we want to do it in place
3631 so all copies of the shared rtx benefit. The call below will
3632 only make substitutions if the resulting address is still
3635 Note that we cannot pass X as the object in the recursive call
3636 since the insn being processed may not allow all valid
3637 addresses. However, if we were not passed on object, we can
3638 only modify X without copying it if X will have a valid
3641 ??? Also note that this can still lose if OBJECT is an insn that
3642 has less restrictions on an address that some other insn.
3643 In that case, we will modify the shared address. This case
3644 doesn't seem very likely, though. One case where this could
3645 happen is in the case of a USE or CLOBBER reference, but we
3646 take care of that below. */
3648 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
3649 object ? object : x, 0))
3652 /* Otherwise make a copy and process that copy. We copy the entire
3653 RTL expression since it might be a PLUS which could also be
3655 *loc = x = copy_rtx (x);
3658 /* Fall through to generic unary operation case. */
3660 case STRICT_LOW_PART:
3662 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
3663 case SIGN_EXTEND: case ZERO_EXTEND:
3664 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
3665 case FLOAT: case FIX:
3666 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
3670 /* These case either have just one operand or we know that we need not
3671 check the rest of the operands. */
3677 /* If the operand is a MEM, see if the change is a valid MEM. If not,
3678 go ahead and make the invalid one, but do it to a copy. For a REG,
3679 just make the recursive call, since there's no chance of a problem. */
3681 if ((GET_CODE (XEXP (x, 0)) == MEM
3682 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
3684 || (GET_CODE (XEXP (x, 0)) == REG
3685 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
3688 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
3693 /* Try to replace with a PLUS. If that doesn't work, compute the sum
3694 in front of this insn and substitute the temporary. */
3695 if (x == virtual_incoming_args_rtx)
3696 new = arg_pointer_rtx, offset = in_arg_offset;
3697 else if (x == virtual_stack_vars_rtx)
3698 new = frame_pointer_rtx, offset = var_offset;
3699 else if (x == virtual_stack_dynamic_rtx)
3700 new = stack_pointer_rtx, offset = dynamic_offset;
3701 else if (x == virtual_outgoing_args_rtx)
3702 new = stack_pointer_rtx, offset = out_arg_offset;
3703 else if (x == virtual_cfa_rtx)
3704 new = arg_pointer_rtx, offset = cfa_offset;
3708 temp = plus_constant (new, offset);
3709 if (!validate_change (object, loc, temp, 0))
3715 temp = force_operand (temp, NULL_RTX);
3719 emit_insns_before (seq, object);
3720 if (! validate_change (object, loc, temp, 0)
3721 && ! validate_replace_rtx (x, temp, object))
3729 if (GET_CODE (XEXP (x, 0)) == REG)
3732 else if (GET_CODE (XEXP (x, 0)) == MEM)
3734 /* If we have a (addressof (mem ..)), do any instantiation inside
3735 since we know we'll be making the inside valid when we finally
3736 remove the ADDRESSOF. */
3737 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
3746 /* Scan all subexpressions. */
3747 fmt = GET_RTX_FORMAT (code);
3748 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3751 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
3754 else if (*fmt == 'E')
3755 for (j = 0; j < XVECLEN (x, i); j++)
3756 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
3763 /* Optimization: assuming this function does not receive nonlocal gotos,
3764 delete the handlers for such, as well as the insns to establish
3765 and disestablish them. */
3771 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3773 /* Delete the handler by turning off the flag that would
3774 prevent jump_optimize from deleting it.
3775 Also permit deletion of the nonlocal labels themselves
3776 if nothing local refers to them. */
3777 if (GET_CODE (insn) == CODE_LABEL)
3781 LABEL_PRESERVE_P (insn) = 0;
3783 /* Remove it from the nonlocal_label list, to avoid confusing
3785 for (t = nonlocal_labels, last_t = 0; t;
3786 last_t = t, t = TREE_CHAIN (t))
3787 if (DECL_RTL (TREE_VALUE (t)) == insn)
3792 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
3794 TREE_CHAIN (last_t) = TREE_CHAIN (t);
3797 if (GET_CODE (insn) == INSN)
3801 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
3802 if (reg_mentioned_p (t, PATTERN (insn)))
3808 || (nonlocal_goto_stack_level != 0
3809 && reg_mentioned_p (nonlocal_goto_stack_level,
3816 /* Output a USE for any register use in RTL.
3817 This is used with -noreg to mark the extent of lifespan
3818 of any registers used in a user-visible variable's DECL_RTL. */
3824 if (GET_CODE (rtl) == REG)
3825 /* This is a register variable. */
3826 emit_insn (gen_rtx_USE (VOIDmode, rtl));
3827 else if (GET_CODE (rtl) == MEM
3828 && GET_CODE (XEXP (rtl, 0)) == REG
3829 && (REGNO (XEXP (rtl, 0)) < FIRST_VIRTUAL_REGISTER
3830 || REGNO (XEXP (rtl, 0)) > LAST_VIRTUAL_REGISTER)
3831 && XEXP (rtl, 0) != current_function_internal_arg_pointer)
3832 /* This is a variable-sized structure. */
3833 emit_insn (gen_rtx_USE (VOIDmode, XEXP (rtl, 0)));
3836 /* Like use_variable except that it outputs the USEs after INSN
3837 instead of at the end of the insn-chain. */
3840 use_variable_after (rtl, insn)
3843 if (GET_CODE (rtl) == REG)
3844 /* This is a register variable. */
3845 emit_insn_after (gen_rtx_USE (VOIDmode, rtl), insn);
3846 else if (GET_CODE (rtl) == MEM
3847 && GET_CODE (XEXP (rtl, 0)) == REG
3848 && (REGNO (XEXP (rtl, 0)) < FIRST_VIRTUAL_REGISTER
3849 || REGNO (XEXP (rtl, 0)) > LAST_VIRTUAL_REGISTER)
3850 && XEXP (rtl, 0) != current_function_internal_arg_pointer)
3851 /* This is a variable-sized structure. */
3852 emit_insn_after (gen_rtx_USE (VOIDmode, XEXP (rtl, 0)), insn);
3858 return max_parm_reg;
3861 /* Return the first insn following those generated by `assign_parms'. */
3864 get_first_nonparm_insn ()
3867 return NEXT_INSN (last_parm_insn);
3868 return get_insns ();
3871 /* Return the first NOTE_INSN_BLOCK_BEG note in the function.
3872 Crash if there is none. */
3875 get_first_block_beg ()
3877 register rtx searcher;
3878 register rtx insn = get_first_nonparm_insn ();
3880 for (searcher = insn; searcher; searcher = NEXT_INSN (searcher))
3881 if (GET_CODE (searcher) == NOTE
3882 && NOTE_LINE_NUMBER (searcher) == NOTE_INSN_BLOCK_BEG)
3885 abort (); /* Invalid call to this function. (See comments above.) */
3889 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
3890 This means a type for which function calls must pass an address to the
3891 function or get an address back from the function.
3892 EXP may be a type node or an expression (whose type is tested). */
3895 aggregate_value_p (exp)
3898 int i, regno, nregs;
3901 if (TREE_CODE_CLASS (TREE_CODE (exp)) == 't')
3904 type = TREE_TYPE (exp);
3906 if (RETURN_IN_MEMORY (type))
3908 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
3909 and thus can't be returned in registers. */
3910 if (TREE_ADDRESSABLE (type))
3912 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
3914 /* Make sure we have suitable call-clobbered regs to return
3915 the value in; if not, we must return it in memory. */
3916 reg = hard_function_value (type, 0);
3918 /* If we have something other than a REG (e.g. a PARALLEL), then assume
3920 if (GET_CODE (reg) != REG)
3923 regno = REGNO (reg);
3924 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
3925 for (i = 0; i < nregs; i++)
3926 if (! call_used_regs[regno + i])
3931 /* Assign RTL expressions to the function's parameters.
3932 This may involve copying them into registers and using
3933 those registers as the RTL for them. */
3936 assign_parms (fndecl)
3940 register rtx entry_parm = 0;
3941 register rtx stack_parm = 0;
3942 CUMULATIVE_ARGS args_so_far;
3943 enum machine_mode promoted_mode, passed_mode;
3944 enum machine_mode nominal_mode, promoted_nominal_mode;
3946 /* Total space needed so far for args on the stack,
3947 given as a constant and a tree-expression. */
3948 struct args_size stack_args_size;
3949 tree fntype = TREE_TYPE (fndecl);
3950 tree fnargs = DECL_ARGUMENTS (fndecl);
3951 /* This is used for the arg pointer when referring to stack args. */
3952 rtx internal_arg_pointer;
3953 /* This is a dummy PARM_DECL that we used for the function result if
3954 the function returns a structure. */
3955 tree function_result_decl = 0;
3956 #ifdef SETUP_INCOMING_VARARGS
3957 int varargs_setup = 0;
3959 rtx conversion_insns = 0;
3961 /* Nonzero if the last arg is named `__builtin_va_alist',
3962 which is used on some machines for old-fashioned non-ANSI varargs.h;
3963 this should be stuck onto the stack as if it had arrived there. */
3965 = (current_function_varargs
3967 && (parm = tree_last (fnargs)) != 0
3969 && (! strcmp (IDENTIFIER_POINTER (DECL_NAME (parm)),
3970 "__builtin_va_alist")));
3972 /* Nonzero if function takes extra anonymous args.
3973 This means the last named arg must be on the stack
3974 right before the anonymous ones. */
3976 = (TYPE_ARG_TYPES (fntype) != 0
3977 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
3978 != void_type_node));
3980 current_function_stdarg = stdarg;
3982 /* If the reg that the virtual arg pointer will be translated into is
3983 not a fixed reg or is the stack pointer, make a copy of the virtual
3984 arg pointer, and address parms via the copy. The frame pointer is
3985 considered fixed even though it is not marked as such.
3987 The second time through, simply use ap to avoid generating rtx. */
3989 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
3990 || ! (fixed_regs[ARG_POINTER_REGNUM]
3991 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
3992 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
3994 internal_arg_pointer = virtual_incoming_args_rtx;
3995 current_function_internal_arg_pointer = internal_arg_pointer;
3997 stack_args_size.constant = 0;
3998 stack_args_size.var = 0;
4000 /* If struct value address is treated as the first argument, make it so. */
4001 if (aggregate_value_p (DECL_RESULT (fndecl))
4002 && ! current_function_returns_pcc_struct
4003 && struct_value_incoming_rtx == 0)
4005 tree type = build_pointer_type (TREE_TYPE (fntype));
4007 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4009 DECL_ARG_TYPE (function_result_decl) = type;
4010 TREE_CHAIN (function_result_decl) = fnargs;
4011 fnargs = function_result_decl;
4014 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4015 parm_reg_stack_loc = (rtx *) xcalloc (max_parm_reg, sizeof (rtx));
4017 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4018 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4020 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, 0);
4023 /* We haven't yet found an argument that we must push and pretend the
4025 current_function_pretend_args_size = 0;
4027 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4029 int aggregate = AGGREGATE_TYPE_P (TREE_TYPE (parm));
4030 struct args_size stack_offset;
4031 struct args_size arg_size;
4032 int passed_pointer = 0;
4033 int did_conversion = 0;
4034 tree passed_type = DECL_ARG_TYPE (parm);
4035 tree nominal_type = TREE_TYPE (parm);
4038 /* Set LAST_NAMED if this is last named arg before some
4040 int last_named = ((TREE_CHAIN (parm) == 0
4041 || DECL_NAME (TREE_CHAIN (parm)) == 0)
4042 && (stdarg || current_function_varargs));
4043 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4044 most machines, if this is a varargs/stdarg function, then we treat
4045 the last named arg as if it were anonymous too. */
4046 int named_arg = STRICT_ARGUMENT_NAMING ? 1 : ! last_named;
4048 if (TREE_TYPE (parm) == error_mark_node
4049 /* This can happen after weird syntax errors
4050 or if an enum type is defined among the parms. */
4051 || TREE_CODE (parm) != PARM_DECL
4052 || passed_type == NULL)
4054 DECL_INCOMING_RTL (parm) = DECL_RTL (parm)
4055 = gen_rtx_MEM (BLKmode, const0_rtx);
4056 TREE_USED (parm) = 1;
4060 /* For varargs.h function, save info about regs and stack space
4061 used by the individual args, not including the va_alist arg. */
4062 if (hide_last_arg && last_named)
4063 current_function_args_info = args_so_far;
4065 /* Find mode of arg as it is passed, and mode of arg
4066 as it should be during execution of this function. */
4067 passed_mode = TYPE_MODE (passed_type);
4068 nominal_mode = TYPE_MODE (nominal_type);
4070 /* If the parm's mode is VOID, its value doesn't matter,
4071 and avoid the usual things like emit_move_insn that could crash. */
4072 if (nominal_mode == VOIDmode)
4074 DECL_INCOMING_RTL (parm) = DECL_RTL (parm) = const0_rtx;
4078 /* If the parm is to be passed as a transparent union, use the
4079 type of the first field for the tests below. We have already
4080 verified that the modes are the same. */
4081 if (DECL_TRANSPARENT_UNION (parm)
4082 || TYPE_TRANSPARENT_UNION (passed_type))
4083 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4085 /* See if this arg was passed by invisible reference. It is if
4086 it is an object whose size depends on the contents of the
4087 object itself or if the machine requires these objects be passed
4090 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
4091 && contains_placeholder_p (TYPE_SIZE (passed_type)))
4092 || TREE_ADDRESSABLE (passed_type)
4093 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4094 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4095 passed_type, named_arg)
4099 passed_type = nominal_type = build_pointer_type (passed_type);
4101 passed_mode = nominal_mode = Pmode;
4104 promoted_mode = passed_mode;
4106 #ifdef PROMOTE_FUNCTION_ARGS
4107 /* Compute the mode in which the arg is actually extended to. */
4108 unsignedp = TREE_UNSIGNED (passed_type);
4109 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4112 /* Let machine desc say which reg (if any) the parm arrives in.
4113 0 means it arrives on the stack. */
4114 #ifdef FUNCTION_INCOMING_ARG
4115 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4116 passed_type, named_arg);
4118 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4119 passed_type, named_arg);
4122 if (entry_parm == 0)
4123 promoted_mode = passed_mode;
4125 #ifdef SETUP_INCOMING_VARARGS
4126 /* If this is the last named parameter, do any required setup for
4127 varargs or stdargs. We need to know about the case of this being an
4128 addressable type, in which case we skip the registers it
4129 would have arrived in.
4131 For stdargs, LAST_NAMED will be set for two parameters, the one that
4132 is actually the last named, and the dummy parameter. We only
4133 want to do this action once.
4135 Also, indicate when RTL generation is to be suppressed. */
4136 if (last_named && !varargs_setup)
4138 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
4139 current_function_pretend_args_size, 0);
4144 /* Determine parm's home in the stack,
4145 in case it arrives in the stack or we should pretend it did.
4147 Compute the stack position and rtx where the argument arrives
4150 There is one complexity here: If this was a parameter that would
4151 have been passed in registers, but wasn't only because it is
4152 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4153 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4154 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4155 0 as it was the previous time. */
4157 pretend_named = named_arg || PRETEND_OUTGOING_VARARGS_NAMED;
4158 locate_and_pad_parm (promoted_mode, passed_type,
4159 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4162 #ifdef FUNCTION_INCOMING_ARG
4163 FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4165 pretend_named) != 0,
4167 FUNCTION_ARG (args_so_far, promoted_mode,
4169 pretend_named) != 0,
4172 fndecl, &stack_args_size, &stack_offset, &arg_size);
4175 rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
4177 if (offset_rtx == const0_rtx)
4178 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4180 stack_parm = gen_rtx_MEM (promoted_mode,
4181 gen_rtx_PLUS (Pmode,
4182 internal_arg_pointer,
4185 /* If this is a memory ref that contains aggregate components,
4186 mark it as such for cse and loop optimize. Likewise if it
4188 MEM_SET_IN_STRUCT_P (stack_parm, aggregate);
4189 RTX_UNCHANGING_P (stack_parm) = TREE_READONLY (parm);
4190 MEM_ALIAS_SET (stack_parm) = get_alias_set (parm);
4193 /* If this parameter was passed both in registers and in the stack,
4194 use the copy on the stack. */
4195 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4198 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4199 /* If this parm was passed part in regs and part in memory,
4200 pretend it arrived entirely in memory
4201 by pushing the register-part onto the stack.
4203 In the special case of a DImode or DFmode that is split,
4204 we could put it together in a pseudoreg directly,
4205 but for now that's not worth bothering with. */
4209 int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4210 passed_type, named_arg);
4214 current_function_pretend_args_size
4215 = (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
4216 / (PARM_BOUNDARY / BITS_PER_UNIT)
4217 * (PARM_BOUNDARY / BITS_PER_UNIT));
4219 /* Handle calls that pass values in multiple non-contiguous
4220 locations. The Irix 6 ABI has examples of this. */
4221 if (GET_CODE (entry_parm) == PARALLEL)
4222 emit_group_store (validize_mem (stack_parm), entry_parm,
4223 int_size_in_bytes (TREE_TYPE (parm)),
4224 (TYPE_ALIGN (TREE_TYPE (parm))
4227 move_block_from_reg (REGNO (entry_parm),
4228 validize_mem (stack_parm), nregs,
4229 int_size_in_bytes (TREE_TYPE (parm)));
4231 entry_parm = stack_parm;
4236 /* If we didn't decide this parm came in a register,
4237 by default it came on the stack. */
4238 if (entry_parm == 0)
4239 entry_parm = stack_parm;
4241 /* Record permanently how this parm was passed. */
4242 DECL_INCOMING_RTL (parm) = entry_parm;
4244 /* If there is actually space on the stack for this parm,
4245 count it in stack_args_size; otherwise set stack_parm to 0
4246 to indicate there is no preallocated stack slot for the parm. */
4248 if (entry_parm == stack_parm
4249 || (GET_CODE (entry_parm) == PARALLEL
4250 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4251 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4252 /* On some machines, even if a parm value arrives in a register
4253 there is still an (uninitialized) stack slot allocated for it.
4255 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4256 whether this parameter already has a stack slot allocated,
4257 because an arg block exists only if current_function_args_size
4258 is larger than some threshold, and we haven't calculated that
4259 yet. So, for now, we just assume that stack slots never exist
4261 || REG_PARM_STACK_SPACE (fndecl) > 0
4265 stack_args_size.constant += arg_size.constant;
4267 ADD_PARM_SIZE (stack_args_size, arg_size.var);
4270 /* No stack slot was pushed for this parm. */
4273 /* Update info on where next arg arrives in registers. */
4275 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4276 passed_type, named_arg);
4278 /* If we can't trust the parm stack slot to be aligned enough
4279 for its ultimate type, don't use that slot after entry.
4280 We'll make another stack slot, if we need one. */
4282 int thisparm_boundary
4283 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4285 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4289 /* If parm was passed in memory, and we need to convert it on entry,
4290 don't store it back in that same slot. */
4292 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4296 /* Now adjust STACK_PARM to the mode and precise location
4297 where this parameter should live during execution,
4298 if we discover that it must live in the stack during execution.
4299 To make debuggers happier on big-endian machines, we store
4300 the value in the last bytes of the space available. */
4302 if (nominal_mode != BLKmode && nominal_mode != passed_mode
4307 if (BYTES_BIG_ENDIAN
4308 && GET_MODE_SIZE (nominal_mode) < UNITS_PER_WORD)
4309 stack_offset.constant += (GET_MODE_SIZE (passed_mode)
4310 - GET_MODE_SIZE (nominal_mode));
4312 offset_rtx = ARGS_SIZE_RTX (stack_offset);
4313 if (offset_rtx == const0_rtx)
4314 stack_parm = gen_rtx_MEM (nominal_mode, internal_arg_pointer);
4316 stack_parm = gen_rtx_MEM (nominal_mode,
4317 gen_rtx_PLUS (Pmode,
4318 internal_arg_pointer,
4321 /* If this is a memory ref that contains aggregate components,
4322 mark it as such for cse and loop optimize. */
4323 MEM_SET_IN_STRUCT_P (stack_parm, aggregate);
4327 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4328 in the mode in which it arrives.
4329 STACK_PARM is an RTX for a stack slot where the parameter can live
4330 during the function (in case we want to put it there).
4331 STACK_PARM is 0 if no stack slot was pushed for it.
4333 Now output code if necessary to convert ENTRY_PARM to
4334 the type in which this function declares it,
4335 and store that result in an appropriate place,
4336 which may be a pseudo reg, may be STACK_PARM,
4337 or may be a local stack slot if STACK_PARM is 0.
4339 Set DECL_RTL to that place. */
4341 if (nominal_mode == BLKmode || GET_CODE (entry_parm) == PARALLEL)
4343 /* If a BLKmode arrives in registers, copy it to a stack slot.
4344 Handle calls that pass values in multiple non-contiguous
4345 locations. The Irix 6 ABI has examples of this. */
4346 if (GET_CODE (entry_parm) == REG
4347 || GET_CODE (entry_parm) == PARALLEL)
4350 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
4353 /* Note that we will be storing an integral number of words.
4354 So we have to be careful to ensure that we allocate an
4355 integral number of words. We do this below in the
4356 assign_stack_local if space was not allocated in the argument
4357 list. If it was, this will not work if PARM_BOUNDARY is not
4358 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4359 if it becomes a problem. */
4361 if (stack_parm == 0)
4364 = assign_stack_local (GET_MODE (entry_parm),
4367 /* If this is a memory ref that contains aggregate
4368 components, mark it as such for cse and loop optimize. */
4369 MEM_SET_IN_STRUCT_P (stack_parm, aggregate);
4372 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4375 if (TREE_READONLY (parm))
4376 RTX_UNCHANGING_P (stack_parm) = 1;
4378 /* Handle calls that pass values in multiple non-contiguous
4379 locations. The Irix 6 ABI has examples of this. */
4380 if (GET_CODE (entry_parm) == PARALLEL)
4381 emit_group_store (validize_mem (stack_parm), entry_parm,
4382 int_size_in_bytes (TREE_TYPE (parm)),
4383 (TYPE_ALIGN (TREE_TYPE (parm))
4386 move_block_from_reg (REGNO (entry_parm),
4387 validize_mem (stack_parm),
4388 size_stored / UNITS_PER_WORD,
4389 int_size_in_bytes (TREE_TYPE (parm)));
4391 DECL_RTL (parm) = stack_parm;
4393 else if (! ((obey_regdecls && ! DECL_REGISTER (parm)
4394 && ! DECL_INLINE (fndecl))
4395 /* layout_decl may set this. */
4396 || TREE_ADDRESSABLE (parm)
4397 || TREE_SIDE_EFFECTS (parm)
4398 /* If -ffloat-store specified, don't put explicit
4399 float variables into registers. */
4400 || (flag_float_store
4401 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4402 /* Always assign pseudo to structure return or item passed
4403 by invisible reference. */
4404 || passed_pointer || parm == function_result_decl)
4406 /* Store the parm in a pseudoregister during the function, but we
4407 may need to do it in a wider mode. */
4409 register rtx parmreg;
4410 int regno, regnoi = 0, regnor = 0;
4412 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4414 promoted_nominal_mode
4415 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4417 parmreg = gen_reg_rtx (promoted_nominal_mode);
4418 mark_user_reg (parmreg);
4420 /* If this was an item that we received a pointer to, set DECL_RTL
4425 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)), parmreg);
4426 MEM_SET_IN_STRUCT_P (DECL_RTL (parm), aggregate);
4429 DECL_RTL (parm) = parmreg;
4431 /* Copy the value into the register. */
4432 if (nominal_mode != passed_mode
4433 || promoted_nominal_mode != promoted_mode)
4436 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4437 mode, by the caller. We now have to convert it to
4438 NOMINAL_MODE, if different. However, PARMREG may be in
4439 a different mode than NOMINAL_MODE if it is being stored
4442 If ENTRY_PARM is a hard register, it might be in a register
4443 not valid for operating in its mode (e.g., an odd-numbered
4444 register for a DFmode). In that case, moves are the only
4445 thing valid, so we can't do a convert from there. This
4446 occurs when the calling sequence allow such misaligned
4449 In addition, the conversion may involve a call, which could
4450 clobber parameters which haven't been copied to pseudo
4451 registers yet. Therefore, we must first copy the parm to
4452 a pseudo reg here, and save the conversion until after all
4453 parameters have been moved. */
4455 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4457 emit_move_insn (tempreg, validize_mem (entry_parm));
4459 push_to_sequence (conversion_insns);
4460 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4462 /* TREE_USED gets set erroneously during expand_assignment. */
4463 save_tree_used = TREE_USED (parm);
4464 expand_assignment (parm,
4465 make_tree (nominal_type, tempreg), 0, 0);
4466 TREE_USED (parm) = save_tree_used;
4467 conversion_insns = get_insns ();
4472 emit_move_insn (parmreg, validize_mem (entry_parm));
4474 /* If we were passed a pointer but the actual value
4475 can safely live in a register, put it in one. */
4476 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4477 && ! ((obey_regdecls && ! DECL_REGISTER (parm)
4478 && ! DECL_INLINE (fndecl))
4479 /* layout_decl may set this. */
4480 || TREE_ADDRESSABLE (parm)
4481 || TREE_SIDE_EFFECTS (parm)
4482 /* If -ffloat-store specified, don't put explicit
4483 float variables into registers. */
4484 || (flag_float_store
4485 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE)))
4487 /* We can't use nominal_mode, because it will have been set to
4488 Pmode above. We must use the actual mode of the parm. */
4489 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4490 mark_user_reg (parmreg);
4491 emit_move_insn (parmreg, DECL_RTL (parm));
4492 DECL_RTL (parm) = parmreg;
4493 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4497 #ifdef FUNCTION_ARG_CALLEE_COPIES
4498 /* If we are passed an arg by reference and it is our responsibility
4499 to make a copy, do it now.
4500 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4501 original argument, so we must recreate them in the call to
4502 FUNCTION_ARG_CALLEE_COPIES. */
4503 /* ??? Later add code to handle the case that if the argument isn't
4504 modified, don't do the copy. */
4506 else if (passed_pointer
4507 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4508 TYPE_MODE (DECL_ARG_TYPE (parm)),
4509 DECL_ARG_TYPE (parm),
4511 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4514 tree type = DECL_ARG_TYPE (parm);
4516 /* This sequence may involve a library call perhaps clobbering
4517 registers that haven't been copied to pseudos yet. */
4519 push_to_sequence (conversion_insns);
4521 if (TYPE_SIZE (type) == 0
4522 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4523 /* This is a variable sized object. */
4524 copy = gen_rtx_MEM (BLKmode,
4525 allocate_dynamic_stack_space
4526 (expr_size (parm), NULL_RTX,
4527 TYPE_ALIGN (type)));
4529 copy = assign_stack_temp (TYPE_MODE (type),
4530 int_size_in_bytes (type), 1);
4531 MEM_SET_IN_STRUCT_P (copy, AGGREGATE_TYPE_P (type));
4532 RTX_UNCHANGING_P (copy) = TREE_READONLY (parm);
4534 store_expr (parm, copy, 0);
4535 emit_move_insn (parmreg, XEXP (copy, 0));
4536 if (current_function_check_memory_usage)
4537 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
4538 XEXP (copy, 0), Pmode,
4539 GEN_INT (int_size_in_bytes (type)),
4540 TYPE_MODE (sizetype),
4541 GEN_INT (MEMORY_USE_RW),
4542 TYPE_MODE (integer_type_node));
4543 conversion_insns = get_insns ();
4547 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4549 /* In any case, record the parm's desired stack location
4550 in case we later discover it must live in the stack.
4552 If it is a COMPLEX value, store the stack location for both
4555 if (GET_CODE (parmreg) == CONCAT)
4556 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4558 regno = REGNO (parmreg);
4560 if (regno >= max_parm_reg)
4563 int old_max_parm_reg = max_parm_reg;
4565 /* It's slow to expand this one register at a time,
4566 but it's also rare and we need max_parm_reg to be
4567 precisely correct. */
4568 max_parm_reg = regno + 1;
4569 new = (rtx *) xrealloc (parm_reg_stack_loc,
4570 max_parm_reg * sizeof (rtx));
4571 bzero ((char *) (new + old_max_parm_reg),
4572 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4573 parm_reg_stack_loc = new;
4576 if (GET_CODE (parmreg) == CONCAT)
4578 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
4580 regnor = REGNO (gen_realpart (submode, parmreg));
4581 regnoi = REGNO (gen_imagpart (submode, parmreg));
4583 if (stack_parm != 0)
4585 parm_reg_stack_loc[regnor]
4586 = gen_realpart (submode, stack_parm);
4587 parm_reg_stack_loc[regnoi]
4588 = gen_imagpart (submode, stack_parm);
4592 parm_reg_stack_loc[regnor] = 0;
4593 parm_reg_stack_loc[regnoi] = 0;
4597 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
4599 /* Mark the register as eliminable if we did no conversion
4600 and it was copied from memory at a fixed offset,
4601 and the arg pointer was not copied to a pseudo-reg.
4602 If the arg pointer is a pseudo reg or the offset formed
4603 an invalid address, such memory-equivalences
4604 as we make here would screw up life analysis for it. */
4605 if (nominal_mode == passed_mode
4608 && GET_CODE (stack_parm) == MEM
4609 && stack_offset.var == 0
4610 && reg_mentioned_p (virtual_incoming_args_rtx,
4611 XEXP (stack_parm, 0)))
4613 rtx linsn = get_last_insn ();
4616 /* Mark complex types separately. */
4617 if (GET_CODE (parmreg) == CONCAT)
4618 /* Scan backwards for the set of the real and
4620 for (sinsn = linsn; sinsn != 0;
4621 sinsn = prev_nonnote_insn (sinsn))
4623 set = single_set (sinsn);
4625 && SET_DEST (set) == regno_reg_rtx [regnoi])
4627 = gen_rtx_EXPR_LIST (REG_EQUIV,
4628 parm_reg_stack_loc[regnoi],
4631 && SET_DEST (set) == regno_reg_rtx [regnor])
4633 = gen_rtx_EXPR_LIST (REG_EQUIV,
4634 parm_reg_stack_loc[regnor],
4637 else if ((set = single_set (linsn)) != 0
4638 && SET_DEST (set) == parmreg)
4640 = gen_rtx_EXPR_LIST (REG_EQUIV,
4641 stack_parm, REG_NOTES (linsn));
4644 /* For pointer data type, suggest pointer register. */
4645 if (POINTER_TYPE_P (TREE_TYPE (parm)))
4646 mark_reg_pointer (parmreg,
4647 (TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm)))
4652 /* Value must be stored in the stack slot STACK_PARM
4653 during function execution. */
4655 if (promoted_mode != nominal_mode)
4657 /* Conversion is required. */
4658 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4660 emit_move_insn (tempreg, validize_mem (entry_parm));
4662 push_to_sequence (conversion_insns);
4663 entry_parm = convert_to_mode (nominal_mode, tempreg,
4664 TREE_UNSIGNED (TREE_TYPE (parm)));
4667 /* ??? This may need a big-endian conversion on sparc64. */
4668 stack_parm = change_address (stack_parm, nominal_mode,
4671 conversion_insns = get_insns ();
4676 if (entry_parm != stack_parm)
4678 if (stack_parm == 0)
4681 = assign_stack_local (GET_MODE (entry_parm),
4682 GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
4683 /* If this is a memory ref that contains aggregate components,
4684 mark it as such for cse and loop optimize. */
4685 MEM_SET_IN_STRUCT_P (stack_parm, aggregate);
4688 if (promoted_mode != nominal_mode)
4690 push_to_sequence (conversion_insns);
4691 emit_move_insn (validize_mem (stack_parm),
4692 validize_mem (entry_parm));
4693 conversion_insns = get_insns ();
4697 emit_move_insn (validize_mem (stack_parm),
4698 validize_mem (entry_parm));
4700 if (current_function_check_memory_usage)
4702 push_to_sequence (conversion_insns);
4703 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
4704 XEXP (stack_parm, 0), Pmode,
4705 GEN_INT (GET_MODE_SIZE (GET_MODE
4707 TYPE_MODE (sizetype),
4708 GEN_INT (MEMORY_USE_RW),
4709 TYPE_MODE (integer_type_node));
4711 conversion_insns = get_insns ();
4714 DECL_RTL (parm) = stack_parm;
4717 /* If this "parameter" was the place where we are receiving the
4718 function's incoming structure pointer, set up the result. */
4719 if (parm == function_result_decl)
4721 tree result = DECL_RESULT (fndecl);
4722 tree restype = TREE_TYPE (result);
4725 = gen_rtx_MEM (DECL_MODE (result), DECL_RTL (parm));
4727 MEM_SET_IN_STRUCT_P (DECL_RTL (result),
4728 AGGREGATE_TYPE_P (restype));
4731 if (TREE_THIS_VOLATILE (parm))
4732 MEM_VOLATILE_P (DECL_RTL (parm)) = 1;
4733 if (TREE_READONLY (parm))
4734 RTX_UNCHANGING_P (DECL_RTL (parm)) = 1;
4737 /* Output all parameter conversion instructions (possibly including calls)
4738 now that all parameters have been copied out of hard registers. */
4739 emit_insns (conversion_insns);
4741 last_parm_insn = get_last_insn ();
4743 current_function_args_size = stack_args_size.constant;
4745 /* Adjust function incoming argument size for alignment and
4748 #ifdef REG_PARM_STACK_SPACE
4749 #ifndef MAYBE_REG_PARM_STACK_SPACE
4750 current_function_args_size = MAX (current_function_args_size,
4751 REG_PARM_STACK_SPACE (fndecl));
4755 #ifdef STACK_BOUNDARY
4756 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
4758 current_function_args_size
4759 = ((current_function_args_size + STACK_BYTES - 1)
4760 / STACK_BYTES) * STACK_BYTES;
4763 #ifdef ARGS_GROW_DOWNWARD
4764 current_function_arg_offset_rtx
4765 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
4766 : expand_expr (size_binop (MINUS_EXPR, stack_args_size.var,
4767 size_int (-stack_args_size.constant)),
4768 NULL_RTX, VOIDmode, EXPAND_MEMORY_USE_BAD));
4770 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
4773 /* See how many bytes, if any, of its args a function should try to pop
4776 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
4777 current_function_args_size);
4779 /* For stdarg.h function, save info about
4780 regs and stack space used by the named args. */
4783 current_function_args_info = args_so_far;
4785 /* Set the rtx used for the function return value. Put this in its
4786 own variable so any optimizers that need this information don't have
4787 to include tree.h. Do this here so it gets done when an inlined
4788 function gets output. */
4790 current_function_return_rtx = DECL_RTL (DECL_RESULT (fndecl));
4793 /* Indicate whether REGNO is an incoming argument to the current function
4794 that was promoted to a wider mode. If so, return the RTX for the
4795 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
4796 that REGNO is promoted from and whether the promotion was signed or
4799 #ifdef PROMOTE_FUNCTION_ARGS
4802 promoted_input_arg (regno, pmode, punsignedp)
4804 enum machine_mode *pmode;
4809 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
4810 arg = TREE_CHAIN (arg))
4811 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
4812 && REGNO (DECL_INCOMING_RTL (arg)) == regno
4813 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
4815 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
4816 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
4818 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
4819 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
4820 && mode != DECL_MODE (arg))
4822 *pmode = DECL_MODE (arg);
4823 *punsignedp = unsignedp;
4824 return DECL_INCOMING_RTL (arg);
4833 /* Compute the size and offset from the start of the stacked arguments for a
4834 parm passed in mode PASSED_MODE and with type TYPE.
4836 INITIAL_OFFSET_PTR points to the current offset into the stacked
4839 The starting offset and size for this parm are returned in *OFFSET_PTR
4840 and *ARG_SIZE_PTR, respectively.
4842 IN_REGS is non-zero if the argument will be passed in registers. It will
4843 never be set if REG_PARM_STACK_SPACE is not defined.
4845 FNDECL is the function in which the argument was defined.
4847 There are two types of rounding that are done. The first, controlled by
4848 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
4849 list to be aligned to the specific boundary (in bits). This rounding
4850 affects the initial and starting offsets, but not the argument size.
4852 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
4853 optionally rounds the size of the parm to PARM_BOUNDARY. The
4854 initial offset is not affected by this rounding, while the size always
4855 is and the starting offset may be. */
4857 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
4858 initial_offset_ptr is positive because locate_and_pad_parm's
4859 callers pass in the total size of args so far as
4860 initial_offset_ptr. arg_size_ptr is always positive.*/
4863 locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
4864 initial_offset_ptr, offset_ptr, arg_size_ptr)
4865 enum machine_mode passed_mode;
4868 tree fndecl ATTRIBUTE_UNUSED;
4869 struct args_size *initial_offset_ptr;
4870 struct args_size *offset_ptr;
4871 struct args_size *arg_size_ptr;
4874 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
4875 enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
4876 int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
4878 #ifdef REG_PARM_STACK_SPACE
4879 /* If we have found a stack parm before we reach the end of the
4880 area reserved for registers, skip that area. */
4883 int reg_parm_stack_space = 0;
4885 #ifdef MAYBE_REG_PARM_STACK_SPACE
4886 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
4888 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
4890 if (reg_parm_stack_space > 0)
4892 if (initial_offset_ptr->var)
4894 initial_offset_ptr->var
4895 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
4896 size_int (reg_parm_stack_space));
4897 initial_offset_ptr->constant = 0;
4899 else if (initial_offset_ptr->constant < reg_parm_stack_space)
4900 initial_offset_ptr->constant = reg_parm_stack_space;
4903 #endif /* REG_PARM_STACK_SPACE */
4905 arg_size_ptr->var = 0;
4906 arg_size_ptr->constant = 0;
4908 #ifdef ARGS_GROW_DOWNWARD
4909 if (initial_offset_ptr->var)
4911 offset_ptr->constant = 0;
4912 offset_ptr->var = size_binop (MINUS_EXPR, integer_zero_node,
4913 initial_offset_ptr->var);
4917 offset_ptr->constant = - initial_offset_ptr->constant;
4918 offset_ptr->var = 0;
4920 if (where_pad != none
4921 && (TREE_CODE (sizetree) != INTEGER_CST
4922 || ((TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)))
4923 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
4924 SUB_PARM_SIZE (*offset_ptr, sizetree);
4925 if (where_pad != downward)
4926 pad_to_arg_alignment (offset_ptr, boundary);
4927 if (initial_offset_ptr->var)
4929 arg_size_ptr->var = size_binop (MINUS_EXPR,
4930 size_binop (MINUS_EXPR,
4932 initial_offset_ptr->var),
4937 arg_size_ptr->constant = (- initial_offset_ptr->constant
4938 - offset_ptr->constant);
4940 #else /* !ARGS_GROW_DOWNWARD */
4941 pad_to_arg_alignment (initial_offset_ptr, boundary);
4942 *offset_ptr = *initial_offset_ptr;
4944 #ifdef PUSH_ROUNDING
4945 if (passed_mode != BLKmode)
4946 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
4949 /* Pad_below needs the pre-rounded size to know how much to pad below
4950 so this must be done before rounding up. */
4951 if (where_pad == downward
4952 /* However, BLKmode args passed in regs have their padding done elsewhere.
4953 The stack slot must be able to hold the entire register. */
4954 && !(in_regs && passed_mode == BLKmode))
4955 pad_below (offset_ptr, passed_mode, sizetree);
4957 if (where_pad != none
4958 && (TREE_CODE (sizetree) != INTEGER_CST
4959 || ((TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)))
4960 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
4962 ADD_PARM_SIZE (*arg_size_ptr, sizetree);
4963 #endif /* ARGS_GROW_DOWNWARD */
4966 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
4967 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
4970 pad_to_arg_alignment (offset_ptr, boundary)
4971 struct args_size *offset_ptr;
4974 int boundary_in_bytes = boundary / BITS_PER_UNIT;
4976 if (boundary > BITS_PER_UNIT)
4978 if (offset_ptr->var)
4981 #ifdef ARGS_GROW_DOWNWARD
4986 (ARGS_SIZE_TREE (*offset_ptr),
4987 boundary / BITS_PER_UNIT);
4988 offset_ptr->constant = 0; /*?*/
4991 offset_ptr->constant =
4992 #ifdef ARGS_GROW_DOWNWARD
4993 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
4995 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
5000 #ifndef ARGS_GROW_DOWNWARD
5002 pad_below (offset_ptr, passed_mode, sizetree)
5003 struct args_size *offset_ptr;
5004 enum machine_mode passed_mode;
5007 if (passed_mode != BLKmode)
5009 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5010 offset_ptr->constant
5011 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5012 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5013 - GET_MODE_SIZE (passed_mode));
5017 if (TREE_CODE (sizetree) != INTEGER_CST
5018 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5020 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5021 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5023 ADD_PARM_SIZE (*offset_ptr, s2);
5024 SUB_PARM_SIZE (*offset_ptr, sizetree);
5030 #ifdef ARGS_GROW_DOWNWARD
5032 round_down (value, divisor)
5036 return size_binop (MULT_EXPR,
5037 size_binop (FLOOR_DIV_EXPR, value, size_int (divisor)),
5038 size_int (divisor));
5042 /* Walk the tree of blocks describing the binding levels within a function
5043 and warn about uninitialized variables.
5044 This is done after calling flow_analysis and before global_alloc
5045 clobbers the pseudo-regs to hard regs. */
5048 uninitialized_vars_warning (block)
5051 register tree decl, sub;
5052 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5054 if (TREE_CODE (decl) == VAR_DECL
5055 /* These warnings are unreliable for and aggregates
5056 because assigning the fields one by one can fail to convince
5057 flow.c that the entire aggregate was initialized.
5058 Unions are troublesome because members may be shorter. */
5059 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5060 && DECL_RTL (decl) != 0
5061 && GET_CODE (DECL_RTL (decl)) == REG
5062 /* Global optimizations can make it difficult to determine if a
5063 particular variable has been initialized. However, a VAR_DECL
5064 with a nonzero DECL_INITIAL had an initializer, so do not
5065 claim it is potentially uninitialized.
5067 We do not care about the actual value in DECL_INITIAL, so we do
5068 not worry that it may be a dangling pointer. */
5069 && DECL_INITIAL (decl) == NULL_TREE
5070 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5071 warning_with_decl (decl,
5072 "`%s' might be used uninitialized in this function");
5073 if (TREE_CODE (decl) == VAR_DECL
5074 && DECL_RTL (decl) != 0
5075 && GET_CODE (DECL_RTL (decl)) == REG
5076 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5077 warning_with_decl (decl,
5078 "variable `%s' might be clobbered by `longjmp' or `vfork'");
5080 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5081 uninitialized_vars_warning (sub);
5084 /* Do the appropriate part of uninitialized_vars_warning
5085 but for arguments instead of local variables. */
5088 setjmp_args_warning ()
5091 for (decl = DECL_ARGUMENTS (current_function_decl);
5092 decl; decl = TREE_CHAIN (decl))
5093 if (DECL_RTL (decl) != 0
5094 && GET_CODE (DECL_RTL (decl)) == REG
5095 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5096 warning_with_decl (decl, "argument `%s' might be clobbered by `longjmp' or `vfork'");
5099 /* If this function call setjmp, put all vars into the stack
5100 unless they were declared `register'. */
5103 setjmp_protect (block)
5106 register tree decl, sub;
5107 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5108 if ((TREE_CODE (decl) == VAR_DECL
5109 || TREE_CODE (decl) == PARM_DECL)
5110 && DECL_RTL (decl) != 0
5111 && (GET_CODE (DECL_RTL (decl)) == REG
5112 || (GET_CODE (DECL_RTL (decl)) == MEM
5113 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5114 /* If this variable came from an inline function, it must be
5115 that its life doesn't overlap the setjmp. If there was a
5116 setjmp in the function, it would already be in memory. We
5117 must exclude such variable because their DECL_RTL might be
5118 set to strange things such as virtual_stack_vars_rtx. */
5119 && ! DECL_FROM_INLINE (decl)
5121 #ifdef NON_SAVING_SETJMP
5122 /* If longjmp doesn't restore the registers,
5123 don't put anything in them. */
5127 ! DECL_REGISTER (decl)))
5128 put_var_into_stack (decl);
5129 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5130 setjmp_protect (sub);
5133 /* Like the previous function, but for args instead of local variables. */
5136 setjmp_protect_args ()
5139 for (decl = DECL_ARGUMENTS (current_function_decl);
5140 decl; decl = TREE_CHAIN (decl))
5141 if ((TREE_CODE (decl) == VAR_DECL
5142 || TREE_CODE (decl) == PARM_DECL)
5143 && DECL_RTL (decl) != 0
5144 && (GET_CODE (DECL_RTL (decl)) == REG
5145 || (GET_CODE (DECL_RTL (decl)) == MEM
5146 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5148 /* If longjmp doesn't restore the registers,
5149 don't put anything in them. */
5150 #ifdef NON_SAVING_SETJMP
5154 ! DECL_REGISTER (decl)))
5155 put_var_into_stack (decl);
5158 /* Return the context-pointer register corresponding to DECL,
5159 or 0 if it does not need one. */
5162 lookup_static_chain (decl)
5165 tree context = decl_function_context (decl);
5169 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5172 /* We treat inline_function_decl as an alias for the current function
5173 because that is the inline function whose vars, types, etc.
5174 are being merged into the current function.
5175 See expand_inline_function. */
5176 if (context == current_function_decl || context == inline_function_decl)
5177 return virtual_stack_vars_rtx;
5179 for (link = context_display; link; link = TREE_CHAIN (link))
5180 if (TREE_PURPOSE (link) == context)
5181 return RTL_EXPR_RTL (TREE_VALUE (link));
5186 /* Convert a stack slot address ADDR for variable VAR
5187 (from a containing function)
5188 into an address valid in this function (using a static chain). */
5191 fix_lexical_addr (addr, var)
5196 HOST_WIDE_INT displacement;
5197 tree context = decl_function_context (var);
5198 struct function *fp;
5201 /* If this is the present function, we need not do anything. */
5202 if (context == current_function_decl || context == inline_function_decl)
5205 for (fp = outer_function_chain; fp; fp = fp->next)
5206 if (fp->decl == context)
5212 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5213 addr = XEXP (XEXP (addr, 0), 0);
5215 /* Decode given address as base reg plus displacement. */
5216 if (GET_CODE (addr) == REG)
5217 basereg = addr, displacement = 0;
5218 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5219 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5223 /* We accept vars reached via the containing function's
5224 incoming arg pointer and via its stack variables pointer. */
5225 if (basereg == fp->internal_arg_pointer)
5227 /* If reached via arg pointer, get the arg pointer value
5228 out of that function's stack frame.
5230 There are two cases: If a separate ap is needed, allocate a
5231 slot in the outer function for it and dereference it that way.
5232 This is correct even if the real ap is actually a pseudo.
5233 Otherwise, just adjust the offset from the frame pointer to
5236 #ifdef NEED_SEPARATE_AP
5239 if (fp->x_arg_pointer_save_area == 0)
5240 fp->x_arg_pointer_save_area
5241 = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, fp);
5243 addr = fix_lexical_addr (XEXP (fp->x_arg_pointer_save_area, 0), var);
5244 addr = memory_address (Pmode, addr);
5246 base = copy_to_reg (gen_rtx_MEM (Pmode, addr));
5248 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5249 base = lookup_static_chain (var);
5253 else if (basereg == virtual_stack_vars_rtx)
5255 /* This is the same code as lookup_static_chain, duplicated here to
5256 avoid an extra call to decl_function_context. */
5259 for (link = context_display; link; link = TREE_CHAIN (link))
5260 if (TREE_PURPOSE (link) == context)
5262 base = RTL_EXPR_RTL (TREE_VALUE (link));
5270 /* Use same offset, relative to appropriate static chain or argument
5272 return plus_constant (base, displacement);
5275 /* Return the address of the trampoline for entering nested fn FUNCTION.
5276 If necessary, allocate a trampoline (in the stack frame)
5277 and emit rtl to initialize its contents (at entry to this function). */
5280 trampoline_address (function)
5286 struct function *fp;
5289 /* Find an existing trampoline and return it. */
5290 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5291 if (TREE_PURPOSE (link) == function)
5293 round_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5295 for (fp = outer_function_chain; fp; fp = fp->next)
5296 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5297 if (TREE_PURPOSE (link) == function)
5299 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5301 return round_trampoline_addr (tramp);
5304 /* None exists; we must make one. */
5306 /* Find the `struct function' for the function containing FUNCTION. */
5308 fn_context = decl_function_context (function);
5309 if (fn_context != current_function_decl
5310 && fn_context != inline_function_decl)
5311 for (fp = outer_function_chain; fp; fp = fp->next)
5312 if (fp->decl == fn_context)
5315 /* Allocate run-time space for this trampoline
5316 (usually in the defining function's stack frame). */
5317 #ifdef ALLOCATE_TRAMPOLINE
5318 tramp = ALLOCATE_TRAMPOLINE (fp);
5320 /* If rounding needed, allocate extra space
5321 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5322 #ifdef TRAMPOLINE_ALIGNMENT
5323 #define TRAMPOLINE_REAL_SIZE \
5324 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5326 #define TRAMPOLINE_REAL_SIZE (TRAMPOLINE_SIZE)
5328 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5329 fp ? fp : current_function);
5332 /* Record the trampoline for reuse and note it for later initialization
5333 by expand_function_end. */
5336 push_obstacks (fp->function_maybepermanent_obstack,
5337 fp->function_maybepermanent_obstack);
5338 rtlexp = make_node (RTL_EXPR);
5339 RTL_EXPR_RTL (rtlexp) = tramp;
5340 fp->x_trampoline_list = tree_cons (function, rtlexp,
5341 fp->x_trampoline_list);
5346 /* Make the RTL_EXPR node temporary, not momentary, so that the
5347 trampoline_list doesn't become garbage. */
5348 int momentary = suspend_momentary ();
5349 rtlexp = make_node (RTL_EXPR);
5350 resume_momentary (momentary);
5352 RTL_EXPR_RTL (rtlexp) = tramp;
5353 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5356 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5357 return round_trampoline_addr (tramp);
5360 /* Given a trampoline address,
5361 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5364 round_trampoline_addr (tramp)
5367 #ifdef TRAMPOLINE_ALIGNMENT
5368 /* Round address up to desired boundary. */
5369 rtx temp = gen_reg_rtx (Pmode);
5370 temp = expand_binop (Pmode, add_optab, tramp,
5371 GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1),
5372 temp, 0, OPTAB_LIB_WIDEN);
5373 tramp = expand_binop (Pmode, and_optab, temp,
5374 GEN_INT (- TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT),
5375 temp, 0, OPTAB_LIB_WIDEN);
5380 /* Insert the BLOCK in the block-tree before LAST_INSN. */
5383 retrofit_block (block, last_insn)
5389 /* Now insert the new BLOCK at the right place in the block trees
5390 for the function which called the inline function. We just look
5391 backwards for a NOTE_INSN_BLOCK_{BEG,END}. If we find the
5392 beginning of a block, then this new block becomes the first
5393 subblock of that block. If we find the end of a block, then this
5394 new block follows that block in the list of blocks. */
5395 for (insn = last_insn; insn; insn = PREV_INSN (insn))
5396 if (GET_CODE (insn) == NOTE
5397 && (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG
5398 || NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END))
5400 if (!insn || NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5405 superblock = NOTE_BLOCK (insn);
5407 superblock = DECL_INITIAL (current_function_decl);
5409 BLOCK_SUPERCONTEXT (block) = superblock;
5410 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (superblock);
5411 BLOCK_SUBBLOCKS (superblock) = block;
5415 tree prevblock = NOTE_BLOCK (insn);
5417 BLOCK_SUPERCONTEXT (block) = BLOCK_SUPERCONTEXT (prevblock);
5418 BLOCK_CHAIN (block) = BLOCK_CHAIN (prevblock);
5419 BLOCK_CHAIN (prevblock) = block;
5423 /* The functions identify_blocks and reorder_blocks provide a way to
5424 reorder the tree of BLOCK nodes, for optimizers that reshuffle or
5425 duplicate portions of the RTL code. Call identify_blocks before
5426 changing the RTL, and call reorder_blocks after. */
5428 /* Put all this function's BLOCK nodes including those that are chained
5429 onto the first block into a vector, and return it.
5430 Also store in each NOTE for the beginning or end of a block
5431 the index of that block in the vector.
5432 The arguments are BLOCK, the chain of top-level blocks of the function,
5433 and INSNS, the insn chain of the function. */
5436 identify_blocks (block, insns)
5444 int current_block_number = 1;
5450 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5451 depth-first order. */
5452 n_blocks = all_blocks (block, 0);
5453 block_vector = (tree *) xmalloc (n_blocks * sizeof (tree));
5454 all_blocks (block, block_vector);
5456 block_stack = (tree *) alloca (n_blocks * sizeof (tree));
5458 for (insn = insns; insn; insn = NEXT_INSN (insn))
5459 if (GET_CODE (insn) == NOTE)
5461 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5465 /* If there are more block notes than BLOCKs, something
5467 if (current_block_number == n_blocks)
5470 b = block_vector[current_block_number++];
5471 NOTE_BLOCK (insn) = b;
5472 block_stack[depth++] = b;
5474 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5477 /* There are more NOTE_INSN_BLOCK_ENDs that
5478 NOTE_INSN_BLOCK_BEGs. Something is badly wrong. */
5481 NOTE_BLOCK (insn) = block_stack[--depth];
5485 /* In whole-function mode, we might not have seen the whole function
5486 yet, so we might not use up all the blocks. */
5487 if (n_blocks != current_block_number
5488 && !current_function->x_whole_function_mode_p)
5491 free (block_vector);
5494 /* Given a revised instruction chain, rebuild the tree structure of
5495 BLOCK nodes to correspond to the new order of RTL. The new block
5496 tree is inserted below TOP_BLOCK. Returns the current top-level
5500 reorder_blocks (block, insns)
5504 tree current_block = block;
5507 if (block == NULL_TREE)
5510 /* Prune the old trees away, so that it doesn't get in the way. */
5511 BLOCK_SUBBLOCKS (current_block) = 0;
5512 BLOCK_CHAIN (current_block) = 0;
5514 for (insn = insns; insn; insn = NEXT_INSN (insn))
5515 if (GET_CODE (insn) == NOTE)
5517 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5519 tree block = NOTE_BLOCK (insn);
5520 /* If we have seen this block before, copy it. */
5521 if (TREE_ASM_WRITTEN (block))
5522 block = copy_node (block);
5523 BLOCK_SUBBLOCKS (block) = 0;
5524 TREE_ASM_WRITTEN (block) = 1;
5525 BLOCK_SUPERCONTEXT (block) = current_block;
5526 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
5527 BLOCK_SUBBLOCKS (current_block) = block;
5528 current_block = block;
5529 NOTE_SOURCE_FILE (insn) = 0;
5531 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5533 BLOCK_SUBBLOCKS (current_block)
5534 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5535 current_block = BLOCK_SUPERCONTEXT (current_block);
5536 NOTE_SOURCE_FILE (insn) = 0;
5540 BLOCK_SUBBLOCKS (current_block)
5541 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5542 return current_block;
5545 /* Reverse the order of elements in the chain T of blocks,
5546 and return the new head of the chain (old last element). */
5552 register tree prev = 0, decl, next;
5553 for (decl = t; decl; decl = next)
5555 next = BLOCK_CHAIN (decl);
5556 BLOCK_CHAIN (decl) = prev;
5562 /* Count the subblocks of the list starting with BLOCK, and list them
5563 all into the vector VECTOR. Also clear TREE_ASM_WRITTEN in all
5567 all_blocks (block, vector)
5575 TREE_ASM_WRITTEN (block) = 0;
5577 /* Record this block. */
5579 vector[n_blocks] = block;
5583 /* Record the subblocks, and their subblocks... */
5584 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
5585 vector ? vector + n_blocks : 0);
5586 block = BLOCK_CHAIN (block);
5592 /* Allocate a function structure and reset its contents to the defaults. */
5594 prepare_function_start ()
5596 current_function = (struct function *) xcalloc (1, sizeof (struct function));
5598 init_stmt_for_function ();
5599 init_eh_for_function ();
5601 cse_not_expected = ! optimize;
5603 /* Caller save not needed yet. */
5604 caller_save_needed = 0;
5606 /* No stack slots have been made yet. */
5607 stack_slot_list = 0;
5609 current_function_has_nonlocal_label = 0;
5610 current_function_has_nonlocal_goto = 0;
5612 /* There is no stack slot for handling nonlocal gotos. */
5613 nonlocal_goto_handler_slots = 0;
5614 nonlocal_goto_stack_level = 0;
5616 /* No labels have been declared for nonlocal use. */
5617 nonlocal_labels = 0;
5618 nonlocal_goto_handler_labels = 0;
5620 /* No function calls so far in this function. */
5621 function_call_count = 0;
5623 /* No parm regs have been allocated.
5624 (This is important for output_inline_function.) */
5625 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
5627 /* Initialize the RTL mechanism. */
5630 /* Initialize the queue of pending postincrement and postdecrements,
5631 and some other info in expr.c. */
5634 /* We haven't done register allocation yet. */
5637 init_varasm_status (current_function);
5639 /* Clear out data used for inlining. */
5640 current_function->inlinable = 0;
5641 current_function->original_decl_initial = 0;
5642 current_function->original_arg_vector = 0;
5644 /* Set if a call to setjmp is seen. */
5645 current_function_calls_setjmp = 0;
5647 /* Set if a call to longjmp is seen. */
5648 current_function_calls_longjmp = 0;
5650 current_function_calls_alloca = 0;
5651 current_function_contains_functions = 0;
5652 current_function_is_leaf = 0;
5653 current_function_sp_is_unchanging = 0;
5654 current_function_uses_only_leaf_regs = 0;
5655 current_function_has_computed_jump = 0;
5656 current_function_is_thunk = 0;
5658 current_function_returns_pcc_struct = 0;
5659 current_function_returns_struct = 0;
5660 current_function_epilogue_delay_list = 0;
5661 current_function_uses_const_pool = 0;
5662 current_function_uses_pic_offset_table = 0;
5663 current_function_cannot_inline = 0;
5665 /* We have not yet needed to make a label to jump to for tail-recursion. */
5666 tail_recursion_label = 0;
5668 /* We haven't had a need to make a save area for ap yet. */
5669 arg_pointer_save_area = 0;
5671 /* No stack slots allocated yet. */
5674 /* No SAVE_EXPRs in this function yet. */
5677 /* No RTL_EXPRs in this function yet. */
5680 /* Set up to allocate temporaries. */
5683 /* Indicate that we need to distinguish between the return value of the
5684 present function and the return value of a function being called. */
5685 rtx_equal_function_value_matters = 1;
5687 /* Indicate that we have not instantiated virtual registers yet. */
5688 virtuals_instantiated = 0;
5690 /* Indicate we have no need of a frame pointer yet. */
5691 frame_pointer_needed = 0;
5693 /* By default assume not varargs or stdarg. */
5694 current_function_varargs = 0;
5695 current_function_stdarg = 0;
5697 /* We haven't made any trampolines for this function yet. */
5698 trampoline_list = 0;
5700 init_pending_stack_adjust ();
5701 inhibit_defer_pop = 0;
5703 current_function_outgoing_args_size = 0;
5705 if (init_lang_status)
5706 (*init_lang_status) (current_function);
5707 if (init_machine_status)
5708 (*init_machine_status) (current_function);
5711 /* Initialize the rtl expansion mechanism so that we can do simple things
5712 like generate sequences. This is used to provide a context during global
5713 initialization of some passes. */
5715 init_dummy_function_start ()
5717 prepare_function_start ();
5720 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
5721 and initialize static variables for generating RTL for the statements
5725 init_function_start (subr, filename, line)
5730 prepare_function_start ();
5732 /* Remember this function for later. */
5733 current_function->next_global = all_functions;
5734 all_functions = current_function;
5736 current_function_name = (*decl_printable_name) (subr, 2);
5737 current_function->decl = subr;
5739 /* Nonzero if this is a nested function that uses a static chain. */
5741 current_function_needs_context
5742 = (decl_function_context (current_function_decl) != 0
5743 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
5745 /* Within function body, compute a type's size as soon it is laid out. */
5746 immediate_size_expand++;
5748 /* Prevent ever trying to delete the first instruction of a function.
5749 Also tell final how to output a linenum before the function prologue.
5750 Note linenums could be missing, e.g. when compiling a Java .class file. */
5752 emit_line_note (filename, line);
5754 /* Make sure first insn is a note even if we don't want linenums.
5755 This makes sure the first insn will never be deleted.
5756 Also, final expects a note to appear there. */
5757 emit_note (NULL_PTR, NOTE_INSN_DELETED);
5759 /* Set flags used by final.c. */
5760 if (aggregate_value_p (DECL_RESULT (subr)))
5762 #ifdef PCC_STATIC_STRUCT_RETURN
5763 current_function_returns_pcc_struct = 1;
5765 current_function_returns_struct = 1;
5768 /* Warn if this value is an aggregate type,
5769 regardless of which calling convention we are using for it. */
5770 if (warn_aggregate_return
5771 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
5772 warning ("function returns an aggregate");
5774 current_function_returns_pointer
5775 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
5778 /* Make sure all values used by the optimization passes have sane
5781 init_function_for_compilation ()
5784 /* No prologue/epilogue insns yet. */
5785 prologue = epilogue = 0;
5788 /* Indicate that the current function uses extra args
5789 not explicitly mentioned in the argument list in any fashion. */
5794 current_function_varargs = 1;
5797 /* Expand a call to __main at the beginning of a possible main function. */
5799 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
5800 #undef HAS_INIT_SECTION
5801 #define HAS_INIT_SECTION
5805 expand_main_function ()
5807 #if !defined (HAS_INIT_SECTION)
5808 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, NAME__MAIN), 0,
5810 #endif /* not HAS_INIT_SECTION */
5813 extern struct obstack permanent_obstack;
5815 /* Start the RTL for a new function, and set variables used for
5817 SUBR is the FUNCTION_DECL node.
5818 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
5819 the function's parameters, which must be run at any return statement. */
5822 expand_function_start (subr, parms_have_cleanups)
5824 int parms_have_cleanups;
5828 rtx last_ptr = NULL_RTX;
5830 /* Make sure volatile mem refs aren't considered
5831 valid operands of arithmetic insns. */
5832 init_recog_no_volatile ();
5834 /* Set this before generating any memory accesses. */
5835 current_function_check_memory_usage
5836 = (flag_check_memory_usage
5837 && ! DECL_NO_CHECK_MEMORY_USAGE (current_function_decl));
5839 current_function_instrument_entry_exit
5840 = (flag_instrument_function_entry_exit
5841 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
5843 /* If function gets a static chain arg, store it in the stack frame.
5844 Do this first, so it gets the first stack slot offset. */
5845 if (current_function_needs_context)
5847 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
5849 /* Delay copying static chain if it is not a register to avoid
5850 conflicts with regs used for parameters. */
5851 if (! SMALL_REGISTER_CLASSES
5852 || GET_CODE (static_chain_incoming_rtx) == REG)
5853 emit_move_insn (last_ptr, static_chain_incoming_rtx);
5856 /* If the parameters of this function need cleaning up, get a label
5857 for the beginning of the code which executes those cleanups. This must
5858 be done before doing anything with return_label. */
5859 if (parms_have_cleanups)
5860 cleanup_label = gen_label_rtx ();
5864 /* Make the label for return statements to jump to, if this machine
5865 does not have a one-instruction return and uses an epilogue,
5866 or if it returns a structure, or if it has parm cleanups. */
5868 if (cleanup_label == 0 && HAVE_return
5869 && ! current_function_instrument_entry_exit
5870 && ! current_function_returns_pcc_struct
5871 && ! (current_function_returns_struct && ! optimize))
5874 return_label = gen_label_rtx ();
5876 return_label = gen_label_rtx ();
5879 /* Initialize rtx used to return the value. */
5880 /* Do this before assign_parms so that we copy the struct value address
5881 before any library calls that assign parms might generate. */
5883 /* Decide whether to return the value in memory or in a register. */
5884 if (aggregate_value_p (DECL_RESULT (subr)))
5886 /* Returning something that won't go in a register. */
5887 register rtx value_address = 0;
5889 #ifdef PCC_STATIC_STRUCT_RETURN
5890 if (current_function_returns_pcc_struct)
5892 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
5893 value_address = assemble_static_space (size);
5898 /* Expect to be passed the address of a place to store the value.
5899 If it is passed as an argument, assign_parms will take care of
5901 if (struct_value_incoming_rtx)
5903 value_address = gen_reg_rtx (Pmode);
5904 emit_move_insn (value_address, struct_value_incoming_rtx);
5909 DECL_RTL (DECL_RESULT (subr))
5910 = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
5911 MEM_SET_IN_STRUCT_P (DECL_RTL (DECL_RESULT (subr)),
5912 AGGREGATE_TYPE_P (TREE_TYPE
5917 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
5918 /* If return mode is void, this decl rtl should not be used. */
5919 DECL_RTL (DECL_RESULT (subr)) = 0;
5920 else if (parms_have_cleanups || current_function_instrument_entry_exit)
5922 /* If function will end with cleanup code for parms,
5923 compute the return values into a pseudo reg,
5924 which we will copy into the true return register
5925 after the cleanups are done. */
5927 enum machine_mode mode = DECL_MODE (DECL_RESULT (subr));
5929 #ifdef PROMOTE_FUNCTION_RETURN
5930 tree type = TREE_TYPE (DECL_RESULT (subr));
5931 int unsignedp = TREE_UNSIGNED (type);
5933 mode = promote_mode (type, mode, &unsignedp, 1);
5936 DECL_RTL (DECL_RESULT (subr)) = gen_reg_rtx (mode);
5939 /* Scalar, returned in a register. */
5941 #ifdef FUNCTION_OUTGOING_VALUE
5942 DECL_RTL (DECL_RESULT (subr))
5943 = FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (subr)), subr);
5945 DECL_RTL (DECL_RESULT (subr))
5946 = FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (subr)), subr);
5949 /* Mark this reg as the function's return value. */
5950 if (GET_CODE (DECL_RTL (DECL_RESULT (subr))) == REG)
5952 REG_FUNCTION_VALUE_P (DECL_RTL (DECL_RESULT (subr))) = 1;
5953 /* Needed because we may need to move this to memory
5954 in case it's a named return value whose address is taken. */
5955 DECL_REGISTER (DECL_RESULT (subr)) = 1;
5959 /* Initialize rtx for parameters and local variables.
5960 In some cases this requires emitting insns. */
5962 assign_parms (subr);
5964 /* Copy the static chain now if it wasn't a register. The delay is to
5965 avoid conflicts with the parameter passing registers. */
5967 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
5968 if (GET_CODE (static_chain_incoming_rtx) != REG)
5969 emit_move_insn (last_ptr, static_chain_incoming_rtx);
5971 /* The following was moved from init_function_start.
5972 The move is supposed to make sdb output more accurate. */
5973 /* Indicate the beginning of the function body,
5974 as opposed to parm setup. */
5975 emit_note (NULL_PTR, NOTE_INSN_FUNCTION_BEG);
5977 /* If doing stupid allocation, mark parms as born here. */
5979 if (GET_CODE (get_last_insn ()) != NOTE)
5980 emit_note (NULL_PTR, NOTE_INSN_DELETED);
5981 parm_birth_insn = get_last_insn ();
5985 for (i = LAST_VIRTUAL_REGISTER + 1; i < max_parm_reg; i++)
5986 use_variable (regno_reg_rtx[i]);
5988 if (current_function_internal_arg_pointer != virtual_incoming_args_rtx)
5989 use_variable (current_function_internal_arg_pointer);
5992 context_display = 0;
5993 if (current_function_needs_context)
5995 /* Fetch static chain values for containing functions. */
5996 tem = decl_function_context (current_function_decl);
5997 /* If not doing stupid register allocation copy the static chain
5998 pointer into a pseudo. If we have small register classes, copy
5999 the value from memory if static_chain_incoming_rtx is a REG. If
6000 we do stupid register allocation, we use the stack address
6002 if (tem && ! obey_regdecls)
6004 /* If the static chain originally came in a register, put it back
6005 there, then move it out in the next insn. The reason for
6006 this peculiar code is to satisfy function integration. */
6007 if (SMALL_REGISTER_CLASSES
6008 && GET_CODE (static_chain_incoming_rtx) == REG)
6009 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6010 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6015 tree rtlexp = make_node (RTL_EXPR);
6017 RTL_EXPR_RTL (rtlexp) = last_ptr;
6018 context_display = tree_cons (tem, rtlexp, context_display);
6019 tem = decl_function_context (tem);
6022 /* Chain thru stack frames, assuming pointer to next lexical frame
6023 is found at the place we always store it. */
6024 #ifdef FRAME_GROWS_DOWNWARD
6025 last_ptr = plus_constant (last_ptr, - GET_MODE_SIZE (Pmode));
6027 last_ptr = copy_to_reg (gen_rtx_MEM (Pmode,
6028 memory_address (Pmode,
6031 /* If we are not optimizing, ensure that we know that this
6032 piece of context is live over the entire function. */
6034 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6039 if (current_function_instrument_entry_exit)
6041 rtx fun = DECL_RTL (current_function_decl);
6042 if (GET_CODE (fun) == MEM)
6043 fun = XEXP (fun, 0);
6046 emit_library_call (profile_function_entry_libfunc, 0, VOIDmode, 2,
6048 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6050 hard_frame_pointer_rtx),
6054 /* After the display initializations is where the tail-recursion label
6055 should go, if we end up needing one. Ensure we have a NOTE here
6056 since some things (like trampolines) get placed before this. */
6057 tail_recursion_reentry = emit_note (NULL_PTR, NOTE_INSN_DELETED);
6059 /* Evaluate now the sizes of any types declared among the arguments. */
6060 for (tem = nreverse (get_pending_sizes ()); tem; tem = TREE_CHAIN (tem))
6062 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode,
6063 EXPAND_MEMORY_USE_BAD);
6064 /* Flush the queue in case this parameter declaration has
6069 /* Make sure there is a line number after the function entry setup code. */
6070 force_next_line_note ();
6073 /* Undo the effects of init_dummy_function_start. */
6075 expand_dummy_function_end ()
6077 /* End any sequences that failed to be closed due to syntax errors. */
6078 while (in_sequence_p ())
6081 /* Outside function body, can't compute type's actual size
6082 until next function's body starts. */
6084 free_after_parsing (current_function);
6085 free_after_compilation (current_function);
6086 free (current_function);
6087 current_function = 0;
6090 /* Generate RTL for the end of the current function.
6091 FILENAME and LINE are the current position in the source file.
6093 It is up to language-specific callers to do cleanups for parameters--
6094 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
6097 expand_function_end (filename, line, end_bindings)
6105 #ifdef TRAMPOLINE_TEMPLATE
6106 static rtx initial_trampoline;
6109 finish_expr_for_function ();
6111 #ifdef NON_SAVING_SETJMP
6112 /* Don't put any variables in registers if we call setjmp
6113 on a machine that fails to restore the registers. */
6114 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6116 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6117 setjmp_protect (DECL_INITIAL (current_function_decl));
6119 setjmp_protect_args ();
6123 /* Save the argument pointer if a save area was made for it. */
6124 if (arg_pointer_save_area)
6126 /* arg_pointer_save_area may not be a valid memory address, so we
6127 have to check it and fix it if necessary. */
6130 emit_move_insn (validize_mem (arg_pointer_save_area),
6131 virtual_incoming_args_rtx);
6132 seq = gen_sequence ();
6134 emit_insn_before (seq, tail_recursion_reentry);
6137 /* Initialize any trampolines required by this function. */
6138 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6140 tree function = TREE_PURPOSE (link);
6141 rtx context = lookup_static_chain (function);
6142 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6143 #ifdef TRAMPOLINE_TEMPLATE
6148 #ifdef TRAMPOLINE_TEMPLATE
6149 /* First make sure this compilation has a template for
6150 initializing trampolines. */
6151 if (initial_trampoline == 0)
6153 end_temporary_allocation ();
6155 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6156 resume_temporary_allocation ();
6158 ggc_add_rtx_root (&initial_trampoline, 1);
6162 /* Generate insns to initialize the trampoline. */
6164 tramp = round_trampoline_addr (XEXP (tramp, 0));
6165 #ifdef TRAMPOLINE_TEMPLATE
6166 blktramp = change_address (initial_trampoline, BLKmode, tramp);
6167 emit_block_move (blktramp, initial_trampoline,
6168 GEN_INT (TRAMPOLINE_SIZE),
6169 TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
6171 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6175 /* Put those insns at entry to the containing function (this one). */
6176 emit_insns_before (seq, tail_recursion_reentry);
6179 /* If we are doing stack checking and this function makes calls,
6180 do a stack probe at the start of the function to ensure we have enough
6181 space for another stack frame. */
6182 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6186 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6187 if (GET_CODE (insn) == CALL_INSN)
6190 probe_stack_range (STACK_CHECK_PROTECT,
6191 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6194 emit_insns_before (seq, tail_recursion_reentry);
6199 /* Warn about unused parms if extra warnings were specified. */
6200 if (warn_unused && extra_warnings)
6204 for (decl = DECL_ARGUMENTS (current_function_decl);
6205 decl; decl = TREE_CHAIN (decl))
6206 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6207 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6208 warning_with_decl (decl, "unused parameter `%s'");
6211 /* Delete handlers for nonlocal gotos if nothing uses them. */
6212 if (nonlocal_goto_handler_slots != 0
6213 && ! current_function_has_nonlocal_label)
6216 /* End any sequences that failed to be closed due to syntax errors. */
6217 while (in_sequence_p ())
6220 /* Outside function body, can't compute type's actual size
6221 until next function's body starts. */
6222 immediate_size_expand--;
6224 /* If doing stupid register allocation,
6225 mark register parms as dying here. */
6230 for (i = LAST_VIRTUAL_REGISTER + 1; i < max_parm_reg; i++)
6231 use_variable (regno_reg_rtx[i]);
6233 /* Likewise for the regs of all the SAVE_EXPRs in the function. */
6235 for (tem = save_expr_regs; tem; tem = XEXP (tem, 1))
6237 use_variable (XEXP (tem, 0));
6238 use_variable_after (XEXP (tem, 0), parm_birth_insn);
6241 if (current_function_internal_arg_pointer != virtual_incoming_args_rtx)
6242 use_variable (current_function_internal_arg_pointer);
6245 clear_pending_stack_adjust ();
6246 do_pending_stack_adjust ();
6248 /* Mark the end of the function body.
6249 If control reaches this insn, the function can drop through
6250 without returning a value. */
6251 emit_note (NULL_PTR, NOTE_INSN_FUNCTION_END);
6253 /* Must mark the last line number note in the function, so that the test
6254 coverage code can avoid counting the last line twice. This just tells
6255 the code to ignore the immediately following line note, since there
6256 already exists a copy of this note somewhere above. This line number
6257 note is still needed for debugging though, so we can't delete it. */
6258 if (flag_test_coverage)
6259 emit_note (NULL_PTR, NOTE_REPEATED_LINE_NUMBER);
6261 /* Output a linenumber for the end of the function.
6262 SDB depends on this. */
6263 emit_line_note_force (filename, line);
6265 /* Output the label for the actual return from the function,
6266 if one is expected. This happens either because a function epilogue
6267 is used instead of a return instruction, or because a return was done
6268 with a goto in order to run local cleanups, or because of pcc-style
6269 structure returning. */
6272 emit_label (return_label);
6274 /* C++ uses this. */
6276 expand_end_bindings (0, 0, 0);
6278 /* Now handle any leftover exception regions that may have been
6279 created for the parameters. */
6281 rtx last = get_last_insn ();
6284 expand_leftover_cleanups ();
6286 /* If the above emitted any code, may sure we jump around it. */
6287 if (last != get_last_insn ())
6289 label = gen_label_rtx ();
6290 last = emit_jump_insn_after (gen_jump (label), last);
6291 last = emit_barrier_after (last);
6296 if (current_function_instrument_entry_exit)
6298 rtx fun = DECL_RTL (current_function_decl);
6299 if (GET_CODE (fun) == MEM)
6300 fun = XEXP (fun, 0);
6303 emit_library_call (profile_function_exit_libfunc, 0, VOIDmode, 2,
6305 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6307 hard_frame_pointer_rtx),
6311 /* If we had calls to alloca, and this machine needs
6312 an accurate stack pointer to exit the function,
6313 insert some code to save and restore the stack pointer. */
6314 #ifdef EXIT_IGNORE_STACK
6315 if (! EXIT_IGNORE_STACK)
6317 if (current_function_calls_alloca)
6321 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
6322 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
6325 /* If scalar return value was computed in a pseudo-reg,
6326 copy that to the hard return register. */
6327 if (DECL_RTL (DECL_RESULT (current_function_decl)) != 0
6328 && GET_CODE (DECL_RTL (DECL_RESULT (current_function_decl))) == REG
6329 && (REGNO (DECL_RTL (DECL_RESULT (current_function_decl)))
6330 >= FIRST_PSEUDO_REGISTER))
6332 rtx real_decl_result;
6334 #ifdef FUNCTION_OUTGOING_VALUE
6336 = FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl)),
6337 current_function_decl);
6340 = FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl)),
6341 current_function_decl);
6343 REG_FUNCTION_VALUE_P (real_decl_result) = 1;
6344 /* If this is a BLKmode structure being returned in registers, then use
6345 the mode computed in expand_return. */
6346 if (GET_MODE (real_decl_result) == BLKmode)
6347 PUT_MODE (real_decl_result,
6348 GET_MODE (DECL_RTL (DECL_RESULT (current_function_decl))));
6349 emit_move_insn (real_decl_result,
6350 DECL_RTL (DECL_RESULT (current_function_decl)));
6351 emit_insn (gen_rtx_USE (VOIDmode, real_decl_result));
6353 /* The delay slot scheduler assumes that current_function_return_rtx
6354 holds the hard register containing the return value, not a temporary
6356 current_function_return_rtx = real_decl_result;
6359 /* If returning a structure, arrange to return the address of the value
6360 in a place where debuggers expect to find it.
6362 If returning a structure PCC style,
6363 the caller also depends on this value.
6364 And current_function_returns_pcc_struct is not necessarily set. */
6365 if (current_function_returns_struct
6366 || current_function_returns_pcc_struct)
6368 rtx value_address = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
6369 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
6370 #ifdef FUNCTION_OUTGOING_VALUE
6372 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
6373 current_function_decl);
6376 = FUNCTION_VALUE (build_pointer_type (type),
6377 current_function_decl);
6380 /* Mark this as a function return value so integrate will delete the
6381 assignment and USE below when inlining this function. */
6382 REG_FUNCTION_VALUE_P (outgoing) = 1;
6384 emit_move_insn (outgoing, value_address);
6385 use_variable (outgoing);
6388 /* If this is an implementation of __throw, do what's necessary to
6389 communicate between __builtin_eh_return and the epilogue. */
6390 expand_eh_return ();
6392 /* Output a return insn if we are using one.
6393 Otherwise, let the rtl chain end here, to drop through
6394 into the epilogue. */
6399 emit_jump_insn (gen_return ());
6404 /* Fix up any gotos that jumped out to the outermost
6405 binding level of the function.
6406 Must follow emitting RETURN_LABEL. */
6408 /* If you have any cleanups to do at this point,
6409 and they need to create temporary variables,
6410 then you will lose. */
6411 expand_fixups (get_insns ());
6414 /* Create an array that records the INSN_UIDs of INSNS (either a sequence
6415 or a single insn). */
6418 record_insns (insns)
6423 if (GET_CODE (insns) == SEQUENCE)
6425 int len = XVECLEN (insns, 0);
6426 vec = (int *) oballoc ((len + 1) * sizeof (int));
6429 vec[len] = INSN_UID (XVECEXP (insns, 0, len));
6433 vec = (int *) oballoc (2 * sizeof (int));
6434 vec[0] = INSN_UID (insns);
6440 /* Determine how many INSN_UIDs in VEC are part of INSN. */
6443 contains (insn, vec)
6449 if (GET_CODE (insn) == INSN
6450 && GET_CODE (PATTERN (insn)) == SEQUENCE)
6453 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
6454 for (j = 0; vec[j]; j++)
6455 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == vec[j])
6461 for (j = 0; vec[j]; j++)
6462 if (INSN_UID (insn) == vec[j])
6469 prologue_epilogue_contains (insn)
6472 if (prologue && contains (insn, prologue))
6474 if (epilogue && contains (insn, epilogue))
6479 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
6480 this into place with notes indicating where the prologue ends and where
6481 the epilogue begins. Update the basic block information when possible. */
6484 thread_prologue_and_epilogue_insns (f)
6485 rtx f ATTRIBUTE_UNUSED;
6489 #ifdef HAVE_prologue
6495 seq = gen_prologue();
6498 /* Retain a map of the prologue insns. */
6499 if (GET_CODE (seq) != SEQUENCE)
6501 prologue = record_insns (seq);
6503 emit_note (NULL, NOTE_INSN_PROLOGUE_END);
6504 seq = gen_sequence ();
6507 /* If optimization is off, and perhaps in an empty function,
6508 the entry block will have no successors. */
6509 if (ENTRY_BLOCK_PTR->succ)
6511 /* Can't deal with multiple successsors of the entry block. */
6512 if (ENTRY_BLOCK_PTR->succ->succ_next)
6515 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
6519 emit_insn_after (seq, f);
6523 #ifdef HAVE_epilogue
6528 rtx tail = get_last_insn ();
6530 /* ??? This is gastly. If function returns were not done via uses,
6531 but via mark_regs_live_at_end, we could use insert_insn_on_edge
6532 and all of this uglyness would go away. */
6537 /* If the exit block has no non-fake predecessors, we don't
6538 need an epilogue. Furthermore, only pay attention to the
6539 fallthru predecessors; if (conditional) return insns were
6540 generated, by definition we do not need to emit epilogue
6543 for (e = EXIT_BLOCK_PTR->pred; e ; e = e->pred_next)
6544 if ((e->flags & EDGE_FAKE) == 0
6545 && (e->flags & EDGE_FALLTHRU) != 0)
6550 /* We can't handle multiple epilogues -- if one is needed,
6551 we won't be able to place it multiple times.
6553 ??? Fix epilogue expanders to not assume they are the
6554 last thing done compiling the function. Either that
6555 or copy_rtx each insn.
6557 ??? Blah, it's not a simple expression to assert that
6558 we've exactly one fallthru exit edge. */
6563 /* ??? If the last insn of the basic block is a jump, then we
6564 are creating a new basic block. Wimp out and leave these
6565 insns outside any block. */
6566 if (GET_CODE (tail) == JUMP_INSN)
6572 rtx prev, seq, first_use;
6574 /* Move the USE insns at the end of a function onto a list. */
6576 if (GET_CODE (prev) == BARRIER
6577 || GET_CODE (prev) == NOTE)
6578 prev = prev_nonnote_insn (prev);
6582 && GET_CODE (prev) == INSN
6583 && GET_CODE (PATTERN (prev)) == USE)
6585 /* If the end of the block is the use, grab hold of something
6586 else so that we emit barriers etc in the right place. */
6590 tail = PREV_INSN (tail);
6591 while (GET_CODE (tail) == INSN
6592 && GET_CODE (PATTERN (tail)) == USE);
6598 prev = prev_nonnote_insn (prev);
6603 NEXT_INSN (use) = first_use;
6604 PREV_INSN (first_use) = use;
6607 NEXT_INSN (use) = NULL_RTX;
6611 && GET_CODE (prev) == INSN
6612 && GET_CODE (PATTERN (prev)) == USE);
6615 /* The last basic block ends with a NOTE_INSN_EPILOGUE_BEG, the
6616 epilogue insns, the USE insns at the end of a function,
6617 the jump insn that returns, and then a BARRIER. */
6619 if (GET_CODE (tail) != BARRIER)
6621 prev = next_nonnote_insn (tail);
6622 if (!prev || GET_CODE (prev) != BARRIER)
6623 emit_barrier_after (tail);
6626 seq = gen_epilogue ();
6628 tail = emit_jump_insn_after (seq, tail);
6630 /* Insert the USE insns immediately before the return insn, which
6631 must be the last instruction emitted in the sequence. */
6633 emit_insns_before (first_use, tail);
6634 emit_note_after (NOTE_INSN_EPILOGUE_BEG, prev);
6636 /* Update the tail of the basic block. */
6640 /* Retain a map of the epilogue insns. */
6641 epilogue = record_insns (GET_CODE (seq) == SEQUENCE ? seq : tail);
6648 commit_edge_insertions ();
6651 /* Reposition the prologue-end and epilogue-begin notes after instruction
6652 scheduling and delayed branch scheduling. */
6655 reposition_prologue_and_epilogue_notes (f)
6656 rtx f ATTRIBUTE_UNUSED;
6658 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
6659 /* Reposition the prologue and epilogue notes. */
6666 register rtx insn, note = 0;
6668 /* Scan from the beginning until we reach the last prologue insn.
6669 We apparently can't depend on basic_block_{head,end} after
6671 for (len = 0; prologue[len]; len++)
6673 for (insn = f; len && insn; insn = NEXT_INSN (insn))
6675 if (GET_CODE (insn) == NOTE)
6677 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
6680 else if ((len -= contains (insn, prologue)) == 0)
6683 /* Find the prologue-end note if we haven't already, and
6684 move it to just after the last prologue insn. */
6687 for (note = insn; (note = NEXT_INSN (note));)
6688 if (GET_CODE (note) == NOTE
6689 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
6693 next = NEXT_INSN (note);
6695 /* Whether or not we can depend on BLOCK_HEAD,
6696 attempt to keep it up-to-date. */
6697 if (BLOCK_HEAD (0) == note)
6698 BLOCK_HEAD (0) = next;
6701 add_insn_after (note, insn);
6708 register rtx insn, note = 0;
6710 /* Scan from the end until we reach the first epilogue insn.
6711 We apparently can't depend on basic_block_{head,end} after
6713 for (len = 0; epilogue[len]; len++)
6715 for (insn = get_last_insn (); len && insn; insn = PREV_INSN (insn))
6717 if (GET_CODE (insn) == NOTE)
6719 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
6722 else if ((len -= contains (insn, epilogue)) == 0)
6724 /* Find the epilogue-begin note if we haven't already, and
6725 move it to just before the first epilogue insn. */
6728 for (note = insn; (note = PREV_INSN (note));)
6729 if (GET_CODE (note) == NOTE
6730 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
6734 /* Whether or not we can depend on BLOCK_HEAD,
6735 attempt to keep it up-to-date. */
6737 && BLOCK_HEAD (n_basic_blocks-1) == insn)
6738 BLOCK_HEAD (n_basic_blocks-1) = note;
6741 add_insn_before (note, insn);
6746 #endif /* HAVE_prologue or HAVE_epilogue */
6749 /* Mark T for GC. */
6753 struct temp_slot *t;
6757 ggc_mark_rtx (t->slot);
6758 ggc_mark_rtx (t->address);
6759 ggc_mark_tree (t->rtl_expr);
6765 /* Mark P for GC. */
6768 mark_function_status (p)
6777 ggc_mark_rtx (p->arg_offset_rtx);
6779 if (p->x_parm_reg_stack_loc)
6780 for (i = p->x_max_parm_reg, r = p->x_parm_reg_stack_loc;
6784 ggc_mark_rtx (p->return_rtx);
6785 ggc_mark_rtx (p->x_cleanup_label);
6786 ggc_mark_rtx (p->x_return_label);
6787 ggc_mark_rtx (p->x_save_expr_regs);
6788 ggc_mark_rtx (p->x_stack_slot_list);
6789 ggc_mark_rtx (p->x_parm_birth_insn);
6790 ggc_mark_rtx (p->x_tail_recursion_label);
6791 ggc_mark_rtx (p->x_tail_recursion_reentry);
6792 ggc_mark_rtx (p->internal_arg_pointer);
6793 ggc_mark_rtx (p->x_arg_pointer_save_area);
6794 ggc_mark_tree (p->x_rtl_expr_chain);
6795 ggc_mark_rtx (p->x_last_parm_insn);
6796 ggc_mark_tree (p->x_context_display);
6797 ggc_mark_tree (p->x_trampoline_list);
6798 ggc_mark_rtx (p->epilogue_delay_list);
6800 mark_temp_slot (p->x_temp_slots);
6803 struct var_refs_queue *q = p->fixup_var_refs_queue;
6806 ggc_mark_rtx (q->modified);
6811 ggc_mark_rtx (p->x_nonlocal_goto_handler_slots);
6812 ggc_mark_rtx (p->x_nonlocal_goto_handler_labels);
6813 ggc_mark_rtx (p->x_nonlocal_goto_stack_level);
6814 ggc_mark_tree (p->x_nonlocal_labels);
6817 /* Mark the function chain ARG (which is really a struct function **)
6821 mark_function_chain (arg)
6824 struct function *f = *(struct function **) arg;
6826 for (; f; f = f->next_global)
6828 ggc_mark_tree (f->decl);
6830 mark_function_status (f);
6831 mark_eh_status (f->eh);
6832 mark_stmt_status (f->stmt);
6833 mark_expr_status (f->expr);
6834 mark_emit_status (f->emit);
6835 mark_varasm_status (f->varasm);
6837 if (mark_machine_status)
6838 (*mark_machine_status) (f);
6839 if (mark_lang_status)
6840 (*mark_lang_status) (f);
6842 if (f->original_arg_vector)
6843 ggc_mark_rtvec ((rtvec) f->original_arg_vector);
6844 if (f->original_decl_initial)
6845 ggc_mark_tree (f->original_decl_initial);
6849 /* Called once, at initialization, to initialize function.c. */
6852 init_function_once ()
6854 ggc_add_root (&all_functions, 1, sizeof all_functions,
6855 mark_function_chain);