1 /* Expands front end tree to back end RTL for GNU C-Compiler
2 Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
5 This file is part of GNU CC.
7 GNU CC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GNU CC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU CC; see the file COPYING. If not, write to
19 the Free Software Foundation, 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
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. */
52 #include "hard-reg-set.h"
53 #include "insn-config.h"
56 #include "basic-block.h"
62 #include "integrate.h"
64 #ifndef TRAMPOLINE_ALIGNMENT
65 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
68 #ifndef LOCAL_ALIGNMENT
69 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
72 /* Some systems use __main in a way incompatible with its use in gcc, in these
73 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
74 give the same symbol without quotes for an alternative entry point. You
75 must define both, or neither. */
77 #define NAME__MAIN "__main"
78 #define SYMBOL__MAIN __main
81 /* Round a value to the lowest integer less than it that is a multiple of
82 the required alignment. Avoid using division in case the value is
83 negative. Assume the alignment is a power of two. */
84 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
86 /* Similar, but round to the next highest integer that meets the
88 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
90 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
91 during rtl generation. If they are different register numbers, this is
92 always true. It may also be true if
93 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
94 generation. See fix_lexical_addr for details. */
96 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
97 #define NEED_SEPARATE_AP
100 /* Nonzero if function being compiled doesn't contain any calls
101 (ignoring the prologue and epilogue). This is set prior to
102 local register allocation and is valid for the remaining
104 int current_function_is_leaf;
106 /* Nonzero if function being compiled doesn't contain any instructions
107 that can throw an exception. This is set prior to final. */
109 int current_function_nothrow;
111 /* Nonzero if function being compiled doesn't modify the stack pointer
112 (ignoring the prologue and epilogue). This is only valid after
113 life_analysis has run. */
114 int current_function_sp_is_unchanging;
116 /* Nonzero if the function being compiled is a leaf function which only
117 uses leaf registers. This is valid after reload (specifically after
118 sched2) and is useful only if the port defines LEAF_REGISTERS. */
119 int current_function_uses_only_leaf_regs;
121 /* Nonzero once virtual register instantiation has been done.
122 assign_stack_local uses frame_pointer_rtx when this is nonzero.
123 calls.c:emit_library_call_value_1 uses it to set up
124 post-instantiation libcalls. */
125 int virtuals_instantiated;
127 /* These variables hold pointers to functions to create and destroy
128 target specific, per-function data structures. */
129 void (*init_machine_status) PARAMS ((struct function *));
130 void (*free_machine_status) PARAMS ((struct function *));
131 /* This variable holds a pointer to a function to register any
132 data items in the target specific, per-function data structure
133 that will need garbage collection. */
134 void (*mark_machine_status) PARAMS ((struct function *));
136 /* Likewise, but for language-specific data. */
137 void (*init_lang_status) PARAMS ((struct function *));
138 void (*save_lang_status) PARAMS ((struct function *));
139 void (*restore_lang_status) PARAMS ((struct function *));
140 void (*mark_lang_status) PARAMS ((struct function *));
141 void (*free_lang_status) PARAMS ((struct function *));
143 /* The FUNCTION_DECL for an inline function currently being expanded. */
144 tree inline_function_decl;
146 /* The currently compiled function. */
147 struct function *cfun = 0;
149 /* Global list of all compiled functions. */
150 struct function *all_functions = 0;
152 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
153 static varray_type prologue;
154 static varray_type epilogue;
156 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
158 static varray_type sibcall_epilogue;
160 /* In order to evaluate some expressions, such as function calls returning
161 structures in memory, we need to temporarily allocate stack locations.
162 We record each allocated temporary in the following structure.
164 Associated with each temporary slot is a nesting level. When we pop up
165 one level, all temporaries associated with the previous level are freed.
166 Normally, all temporaries are freed after the execution of the statement
167 in which they were created. However, if we are inside a ({...}) grouping,
168 the result may be in a temporary and hence must be preserved. If the
169 result could be in a temporary, we preserve it if we can determine which
170 one it is in. If we cannot determine which temporary may contain the
171 result, all temporaries are preserved. A temporary is preserved by
172 pretending it was allocated at the previous nesting level.
174 Automatic variables are also assigned temporary slots, at the nesting
175 level where they are defined. They are marked a "kept" so that
176 free_temp_slots will not free them. */
180 /* Points to next temporary slot. */
181 struct temp_slot *next;
182 /* The rtx to used to reference the slot. */
184 /* The rtx used to represent the address if not the address of the
185 slot above. May be an EXPR_LIST if multiple addresses exist. */
187 /* The alignment (in bits) of the slot. */
189 /* The size, in units, of the slot. */
191 /* The type of the object in the slot, or zero if it doesn't correspond
192 to a type. We use this to determine whether a slot can be reused.
193 It can be reused if objects of the type of the new slot will always
194 conflict with objects of the type of the old slot. */
196 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
198 /* Non-zero if this temporary is currently in use. */
200 /* Non-zero if this temporary has its address taken. */
202 /* Nesting level at which this slot is being used. */
204 /* Non-zero if this should survive a call to free_temp_slots. */
206 /* The offset of the slot from the frame_pointer, including extra space
207 for alignment. This info is for combine_temp_slots. */
208 HOST_WIDE_INT base_offset;
209 /* The size of the slot, including extra space for alignment. This
210 info is for combine_temp_slots. */
211 HOST_WIDE_INT full_size;
214 /* This structure is used to record MEMs or pseudos used to replace VAR, any
215 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
216 maintain this list in case two operands of an insn were required to match;
217 in that case we must ensure we use the same replacement. */
219 struct fixup_replacement
223 struct fixup_replacement *next;
226 struct insns_for_mem_entry {
227 /* The KEY in HE will be a MEM. */
228 struct hash_entry he;
229 /* These are the INSNS which reference the MEM. */
233 /* Forward declarations. */
235 static rtx assign_stack_local_1 PARAMS ((enum machine_mode, HOST_WIDE_INT,
236 int, struct function *));
237 static rtx assign_stack_temp_for_type PARAMS ((enum machine_mode,
238 HOST_WIDE_INT, int, tree));
239 static struct temp_slot *find_temp_slot_from_address PARAMS ((rtx));
240 static void put_reg_into_stack PARAMS ((struct function *, rtx, tree,
241 enum machine_mode, enum machine_mode,
242 int, unsigned int, int,
243 struct hash_table *));
244 static void schedule_fixup_var_refs PARAMS ((struct function *, rtx, tree,
246 struct hash_table *));
247 static void fixup_var_refs PARAMS ((rtx, enum machine_mode, int,
248 struct hash_table *));
249 static struct fixup_replacement
250 *find_fixup_replacement PARAMS ((struct fixup_replacement **, rtx));
251 static void fixup_var_refs_insns PARAMS ((rtx, rtx, enum machine_mode,
253 static void fixup_var_refs_insns_with_hash
254 PARAMS ((struct hash_table *, rtx,
255 enum machine_mode, int));
256 static void fixup_var_refs_insn PARAMS ((rtx, rtx, enum machine_mode,
258 static void fixup_var_refs_1 PARAMS ((rtx, enum machine_mode, rtx *, rtx,
259 struct fixup_replacement **));
260 static rtx fixup_memory_subreg PARAMS ((rtx, rtx, int));
261 static rtx walk_fixup_memory_subreg PARAMS ((rtx, rtx, int));
262 static rtx fixup_stack_1 PARAMS ((rtx, rtx));
263 static void optimize_bit_field PARAMS ((rtx, rtx, rtx *));
264 static void instantiate_decls PARAMS ((tree, int));
265 static void instantiate_decls_1 PARAMS ((tree, int));
266 static void instantiate_decl PARAMS ((rtx, HOST_WIDE_INT, int));
267 static rtx instantiate_new_reg PARAMS ((rtx, HOST_WIDE_INT *));
268 static int instantiate_virtual_regs_1 PARAMS ((rtx *, rtx, int));
269 static void delete_handlers PARAMS ((void));
270 static void pad_to_arg_alignment PARAMS ((struct args_size *, int,
271 struct args_size *));
272 #ifndef ARGS_GROW_DOWNWARD
273 static void pad_below PARAMS ((struct args_size *, enum machine_mode,
276 static rtx round_trampoline_addr PARAMS ((rtx));
277 static rtx adjust_trampoline_addr PARAMS ((rtx));
278 static tree *identify_blocks_1 PARAMS ((rtx, tree *, tree *, tree *));
279 static void reorder_blocks_0 PARAMS ((tree));
280 static void reorder_blocks_1 PARAMS ((rtx, tree, varray_type *));
281 static void reorder_fix_fragments PARAMS ((tree));
282 static tree blocks_nreverse PARAMS ((tree));
283 static int all_blocks PARAMS ((tree, tree *));
284 static tree *get_block_vector PARAMS ((tree, int *));
285 /* We always define `record_insns' even if its not used so that we
286 can always export `prologue_epilogue_contains'. */
287 static void record_insns PARAMS ((rtx, varray_type *)) ATTRIBUTE_UNUSED;
288 static int contains PARAMS ((rtx, varray_type));
290 static void emit_return_into_block PARAMS ((basic_block, rtx));
292 static void put_addressof_into_stack PARAMS ((rtx, struct hash_table *));
293 static bool purge_addressof_1 PARAMS ((rtx *, rtx, int, int,
294 struct hash_table *));
295 static void purge_single_hard_subreg_set PARAMS ((rtx));
297 static void keep_stack_depressed PARAMS ((rtx));
299 static int is_addressof PARAMS ((rtx *, void *));
300 static struct hash_entry *insns_for_mem_newfunc PARAMS ((struct hash_entry *,
303 static unsigned long insns_for_mem_hash PARAMS ((hash_table_key));
304 static bool insns_for_mem_comp PARAMS ((hash_table_key, hash_table_key));
305 static int insns_for_mem_walk PARAMS ((rtx *, void *));
306 static void compute_insns_for_mem PARAMS ((rtx, rtx, struct hash_table *));
307 static void mark_temp_slot PARAMS ((struct temp_slot *));
308 static void mark_function_status PARAMS ((struct function *));
309 static void mark_function_chain PARAMS ((void *));
310 static void prepare_function_start PARAMS ((void));
311 static void do_clobber_return_reg PARAMS ((rtx, void *));
312 static void do_use_return_reg PARAMS ((rtx, void *));
314 /* Pointer to chain of `struct function' for containing functions. */
315 struct function *outer_function_chain;
317 /* Given a function decl for a containing function,
318 return the `struct function' for it. */
321 find_function_data (decl)
326 for (p = outer_function_chain; p; p = p->next)
333 /* Save the current context for compilation of a nested function.
334 This is called from language-specific code. The caller should use
335 the save_lang_status callback to save any language-specific state,
336 since this function knows only about language-independent
340 push_function_context_to (context)
343 struct function *p, *context_data;
347 context_data = (context == current_function_decl
349 : find_function_data (context));
350 context_data->contains_functions = 1;
354 init_dummy_function_start ();
357 p->next = outer_function_chain;
358 outer_function_chain = p;
359 p->fixup_var_refs_queue = 0;
361 if (save_lang_status)
362 (*save_lang_status) (p);
368 push_function_context ()
370 push_function_context_to (current_function_decl);
373 /* Restore the last saved context, at the end of a nested function.
374 This function is called from language-specific code. */
377 pop_function_context_from (context)
378 tree context ATTRIBUTE_UNUSED;
380 struct function *p = outer_function_chain;
381 struct var_refs_queue *queue;
382 struct var_refs_queue *next;
385 outer_function_chain = p->next;
387 current_function_decl = p->decl;
390 restore_emit_status (p);
392 if (restore_lang_status)
393 (*restore_lang_status) (p);
395 /* Finish doing put_var_into_stack for any of our variables
396 which became addressable during the nested function. */
397 for (queue = p->fixup_var_refs_queue; queue; queue = next)
400 fixup_var_refs (queue->modified, queue->promoted_mode,
401 queue->unsignedp, 0);
404 p->fixup_var_refs_queue = 0;
406 /* Reset variables that have known state during rtx generation. */
407 rtx_equal_function_value_matters = 1;
408 virtuals_instantiated = 0;
409 generating_concat_p = 1;
413 pop_function_context ()
415 pop_function_context_from (current_function_decl);
418 /* Clear out all parts of the state in F that can safely be discarded
419 after the function has been parsed, but not compiled, to let
420 garbage collection reclaim the memory. */
423 free_after_parsing (f)
426 /* f->expr->forced_labels is used by code generation. */
427 /* f->emit->regno_reg_rtx is used by code generation. */
428 /* f->varasm is used by code generation. */
429 /* f->eh->eh_return_stub_label is used by code generation. */
431 if (free_lang_status)
432 (*free_lang_status) (f);
433 free_stmt_status (f);
436 /* Clear out all parts of the state in F that can safely be discarded
437 after the function has been compiled, to let garbage collection
438 reclaim the memory. */
441 free_after_compilation (f)
444 struct temp_slot *ts;
445 struct temp_slot *next;
448 free_expr_status (f);
449 free_emit_status (f);
450 free_varasm_status (f);
452 if (free_machine_status)
453 (*free_machine_status) (f);
455 if (f->x_parm_reg_stack_loc)
456 free (f->x_parm_reg_stack_loc);
458 for (ts = f->x_temp_slots; ts; ts = next)
463 f->x_temp_slots = NULL;
465 f->arg_offset_rtx = NULL;
466 f->return_rtx = NULL;
467 f->internal_arg_pointer = NULL;
468 f->x_nonlocal_labels = NULL;
469 f->x_nonlocal_goto_handler_slots = NULL;
470 f->x_nonlocal_goto_handler_labels = NULL;
471 f->x_nonlocal_goto_stack_level = NULL;
472 f->x_cleanup_label = NULL;
473 f->x_return_label = NULL;
474 f->x_save_expr_regs = NULL;
475 f->x_stack_slot_list = NULL;
476 f->x_rtl_expr_chain = NULL;
477 f->x_tail_recursion_label = NULL;
478 f->x_tail_recursion_reentry = NULL;
479 f->x_arg_pointer_save_area = NULL;
480 f->x_clobber_return_insn = NULL;
481 f->x_context_display = NULL;
482 f->x_trampoline_list = NULL;
483 f->x_parm_birth_insn = NULL;
484 f->x_last_parm_insn = NULL;
485 f->x_parm_reg_stack_loc = NULL;
486 f->fixup_var_refs_queue = NULL;
487 f->original_arg_vector = NULL;
488 f->original_decl_initial = NULL;
489 f->inl_last_parm_insn = NULL;
490 f->epilogue_delay_list = NULL;
493 /* Allocate fixed slots in the stack frame of the current function. */
495 /* Return size needed for stack frame based on slots so far allocated in
497 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
498 the caller may have to do that. */
501 get_func_frame_size (f)
504 #ifdef FRAME_GROWS_DOWNWARD
505 return -f->x_frame_offset;
507 return f->x_frame_offset;
511 /* Return size needed for stack frame based on slots so far allocated.
512 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
513 the caller may have to do that. */
517 return get_func_frame_size (cfun);
520 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
521 with machine mode MODE.
523 ALIGN controls the amount of alignment for the address of the slot:
524 0 means according to MODE,
525 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
526 positive specifies alignment boundary in bits.
528 We do not round to stack_boundary here.
530 FUNCTION specifies the function to allocate in. */
533 assign_stack_local_1 (mode, size, align, function)
534 enum machine_mode mode;
537 struct function *function;
539 register rtx x, addr;
540 int bigend_correction = 0;
548 alignment = BIGGEST_ALIGNMENT;
550 alignment = GET_MODE_ALIGNMENT (mode);
552 /* Allow the target to (possibly) increase the alignment of this
554 type = type_for_mode (mode, 0);
556 alignment = LOCAL_ALIGNMENT (type, alignment);
558 alignment /= BITS_PER_UNIT;
560 else if (align == -1)
562 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
563 size = CEIL_ROUND (size, alignment);
566 alignment = align / BITS_PER_UNIT;
568 #ifdef FRAME_GROWS_DOWNWARD
569 function->x_frame_offset -= size;
572 /* Ignore alignment we can't do with expected alignment of the boundary. */
573 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
574 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
576 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
577 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
579 /* Round frame offset to that alignment.
580 We must be careful here, since FRAME_OFFSET might be negative and
581 division with a negative dividend isn't as well defined as we might
582 like. So we instead assume that ALIGNMENT is a power of two and
583 use logical operations which are unambiguous. */
584 #ifdef FRAME_GROWS_DOWNWARD
585 function->x_frame_offset = FLOOR_ROUND (function->x_frame_offset, alignment);
587 function->x_frame_offset = CEIL_ROUND (function->x_frame_offset, alignment);
590 /* On a big-endian machine, if we are allocating more space than we will use,
591 use the least significant bytes of those that are allocated. */
592 if (BYTES_BIG_ENDIAN && mode != BLKmode)
593 bigend_correction = size - GET_MODE_SIZE (mode);
595 /* If we have already instantiated virtual registers, return the actual
596 address relative to the frame pointer. */
597 if (function == cfun && virtuals_instantiated)
598 addr = plus_constant (frame_pointer_rtx,
599 (frame_offset + bigend_correction
600 + STARTING_FRAME_OFFSET));
602 addr = plus_constant (virtual_stack_vars_rtx,
603 function->x_frame_offset + bigend_correction);
605 #ifndef FRAME_GROWS_DOWNWARD
606 function->x_frame_offset += size;
609 x = gen_rtx_MEM (mode, addr);
611 function->x_stack_slot_list
612 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
617 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
621 assign_stack_local (mode, size, align)
622 enum machine_mode mode;
626 return assign_stack_local_1 (mode, size, align, cfun);
629 /* Allocate a temporary stack slot and record it for possible later
632 MODE is the machine mode to be given to the returned rtx.
634 SIZE is the size in units of the space required. We do no rounding here
635 since assign_stack_local will do any required rounding.
637 KEEP is 1 if this slot is to be retained after a call to
638 free_temp_slots. Automatic variables for a block are allocated
639 with this flag. KEEP is 2 if we allocate a longer term temporary,
640 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
641 if we are to allocate something at an inner level to be treated as
642 a variable in the block (e.g., a SAVE_EXPR).
644 TYPE is the type that will be used for the stack slot. */
647 assign_stack_temp_for_type (mode, size, keep, type)
648 enum machine_mode mode;
654 struct temp_slot *p, *best_p = 0;
656 /* If SIZE is -1 it means that somebody tried to allocate a temporary
657 of a variable size. */
662 align = BIGGEST_ALIGNMENT;
664 align = GET_MODE_ALIGNMENT (mode);
667 type = type_for_mode (mode, 0);
670 align = LOCAL_ALIGNMENT (type, align);
672 /* Try to find an available, already-allocated temporary of the proper
673 mode which meets the size and alignment requirements. Choose the
674 smallest one with the closest alignment. */
675 for (p = temp_slots; p; p = p->next)
676 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
678 && objects_must_conflict_p (p->type, type)
679 && (best_p == 0 || best_p->size > p->size
680 || (best_p->size == p->size && best_p->align > p->align)))
682 if (p->align == align && p->size == size)
690 /* Make our best, if any, the one to use. */
693 /* If there are enough aligned bytes left over, make them into a new
694 temp_slot so that the extra bytes don't get wasted. Do this only
695 for BLKmode slots, so that we can be sure of the alignment. */
696 if (GET_MODE (best_p->slot) == BLKmode)
698 int alignment = best_p->align / BITS_PER_UNIT;
699 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
701 if (best_p->size - rounded_size >= alignment)
703 p = (struct temp_slot *) xmalloc (sizeof (struct temp_slot));
704 p->in_use = p->addr_taken = 0;
705 p->size = best_p->size - rounded_size;
706 p->base_offset = best_p->base_offset + rounded_size;
707 p->full_size = best_p->full_size - rounded_size;
708 p->slot = gen_rtx_MEM (BLKmode,
709 plus_constant (XEXP (best_p->slot, 0),
711 p->align = best_p->align;
714 p->type = best_p->type;
715 p->next = temp_slots;
718 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
721 best_p->size = rounded_size;
722 best_p->full_size = rounded_size;
729 /* If we still didn't find one, make a new temporary. */
732 HOST_WIDE_INT frame_offset_old = frame_offset;
734 p = (struct temp_slot *) xmalloc (sizeof (struct temp_slot));
736 /* We are passing an explicit alignment request to assign_stack_local.
737 One side effect of that is assign_stack_local will not round SIZE
738 to ensure the frame offset remains suitably aligned.
740 So for requests which depended on the rounding of SIZE, we go ahead
741 and round it now. We also make sure ALIGNMENT is at least
742 BIGGEST_ALIGNMENT. */
743 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
745 p->slot = assign_stack_local (mode,
747 ? CEIL_ROUND (size, align / BITS_PER_UNIT)
753 /* The following slot size computation is necessary because we don't
754 know the actual size of the temporary slot until assign_stack_local
755 has performed all the frame alignment and size rounding for the
756 requested temporary. Note that extra space added for alignment
757 can be either above or below this stack slot depending on which
758 way the frame grows. We include the extra space if and only if it
759 is above this slot. */
760 #ifdef FRAME_GROWS_DOWNWARD
761 p->size = frame_offset_old - frame_offset;
766 /* Now define the fields used by combine_temp_slots. */
767 #ifdef FRAME_GROWS_DOWNWARD
768 p->base_offset = frame_offset;
769 p->full_size = frame_offset_old - frame_offset;
771 p->base_offset = frame_offset_old;
772 p->full_size = frame_offset - frame_offset_old;
775 p->next = temp_slots;
781 p->rtl_expr = seq_rtl_expr;
786 p->level = target_temp_slot_level;
791 p->level = var_temp_slot_level;
796 p->level = temp_slot_level;
800 /* We may be reusing an old slot, so clear any MEM flags that may have been
802 RTX_UNCHANGING_P (p->slot) = 0;
803 MEM_IN_STRUCT_P (p->slot) = 0;
804 MEM_SCALAR_P (p->slot) = 0;
805 MEM_VOLATILE_P (p->slot) = 0;
807 /* If we know the alias set for the memory that will be used, use
808 it. If there's no TYPE, then we don't know anything about the
809 alias set for the memory. */
810 set_mem_alias_set (p->slot, type ? get_alias_set (type) : 0);
812 /* If a type is specified, set the relevant flags. */
815 RTX_UNCHANGING_P (p->slot) = TYPE_READONLY (type);
816 MEM_VOLATILE_P (p->slot) = TYPE_VOLATILE (type);
817 MEM_SET_IN_STRUCT_P (p->slot, AGGREGATE_TYPE_P (type));
823 /* Allocate a temporary stack slot and record it for possible later
824 reuse. First three arguments are same as in preceding function. */
827 assign_stack_temp (mode, size, keep)
828 enum machine_mode mode;
832 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
835 /* Assign a temporary of given TYPE.
836 KEEP is as for assign_stack_temp.
837 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
838 it is 0 if a register is OK.
839 DONT_PROMOTE is 1 if we should not promote values in register
843 assign_temp (type, keep, memory_required, dont_promote)
847 int dont_promote ATTRIBUTE_UNUSED;
849 enum machine_mode mode = TYPE_MODE (type);
850 #ifndef PROMOTE_FOR_CALL_ONLY
851 int unsignedp = TREE_UNSIGNED (type);
854 if (mode == BLKmode || memory_required)
856 HOST_WIDE_INT size = int_size_in_bytes (type);
859 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
860 problems with allocating the stack space. */
864 /* Unfortunately, we don't yet know how to allocate variable-sized
865 temporaries. However, sometimes we have a fixed upper limit on
866 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
867 instead. This is the case for Chill variable-sized strings. */
868 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
869 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
870 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
871 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
873 tmp = assign_stack_temp_for_type (mode, size, keep, type);
877 #ifndef PROMOTE_FOR_CALL_ONLY
879 mode = promote_mode (type, mode, &unsignedp, 0);
882 return gen_reg_rtx (mode);
885 /* Combine temporary stack slots which are adjacent on the stack.
887 This allows for better use of already allocated stack space. This is only
888 done for BLKmode slots because we can be sure that we won't have alignment
889 problems in this case. */
892 combine_temp_slots ()
894 struct temp_slot *p, *q;
895 struct temp_slot *prev_p, *prev_q;
898 /* We can't combine slots, because the information about which slot
899 is in which alias set will be lost. */
900 if (flag_strict_aliasing)
903 /* If there are a lot of temp slots, don't do anything unless
904 high levels of optimizaton. */
905 if (! flag_expensive_optimizations)
906 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
907 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
910 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
914 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
915 for (q = p->next, prev_q = p; q; q = prev_q->next)
918 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
920 if (p->base_offset + p->full_size == q->base_offset)
922 /* Q comes after P; combine Q into P. */
924 p->full_size += q->full_size;
927 else if (q->base_offset + q->full_size == p->base_offset)
929 /* P comes after Q; combine P into Q. */
931 q->full_size += p->full_size;
936 /* Either delete Q or advance past it. */
939 prev_q->next = q->next;
945 /* Either delete P or advance past it. */
949 prev_p->next = p->next;
951 temp_slots = p->next;
958 /* Find the temp slot corresponding to the object at address X. */
960 static struct temp_slot *
961 find_temp_slot_from_address (x)
967 for (p = temp_slots; p; p = p->next)
972 else if (XEXP (p->slot, 0) == x
974 || (GET_CODE (x) == PLUS
975 && XEXP (x, 0) == virtual_stack_vars_rtx
976 && GET_CODE (XEXP (x, 1)) == CONST_INT
977 && INTVAL (XEXP (x, 1)) >= p->base_offset
978 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
981 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
982 for (next = p->address; next; next = XEXP (next, 1))
983 if (XEXP (next, 0) == x)
987 /* If we have a sum involving a register, see if it points to a temp
989 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == REG
990 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
992 else if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == REG
993 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
999 /* Indicate that NEW is an alternate way of referring to the temp slot
1000 that previously was known by OLD. */
1003 update_temp_slot_address (old, new)
1006 struct temp_slot *p;
1008 if (rtx_equal_p (old, new))
1011 p = find_temp_slot_from_address (old);
1013 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
1014 is a register, see if one operand of the PLUS is a temporary
1015 location. If so, NEW points into it. Otherwise, if both OLD and
1016 NEW are a PLUS and if there is a register in common between them.
1017 If so, try a recursive call on those values. */
1020 if (GET_CODE (old) != PLUS)
1023 if (GET_CODE (new) == REG)
1025 update_temp_slot_address (XEXP (old, 0), new);
1026 update_temp_slot_address (XEXP (old, 1), new);
1029 else if (GET_CODE (new) != PLUS)
1032 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
1033 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
1034 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
1035 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
1036 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
1037 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
1038 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
1039 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
1044 /* Otherwise add an alias for the temp's address. */
1045 else if (p->address == 0)
1049 if (GET_CODE (p->address) != EXPR_LIST)
1050 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1052 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1056 /* If X could be a reference to a temporary slot, mark the fact that its
1057 address was taken. */
1060 mark_temp_addr_taken (x)
1063 struct temp_slot *p;
1068 /* If X is not in memory or is at a constant address, it cannot be in
1069 a temporary slot. */
1070 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1073 p = find_temp_slot_from_address (XEXP (x, 0));
1078 /* If X could be a reference to a temporary slot, mark that slot as
1079 belonging to the to one level higher than the current level. If X
1080 matched one of our slots, just mark that one. Otherwise, we can't
1081 easily predict which it is, so upgrade all of them. Kept slots
1082 need not be touched.
1084 This is called when an ({...}) construct occurs and a statement
1085 returns a value in memory. */
1088 preserve_temp_slots (x)
1091 struct temp_slot *p = 0;
1093 /* If there is no result, we still might have some objects whose address
1094 were taken, so we need to make sure they stay around. */
1097 for (p = temp_slots; p; p = p->next)
1098 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1104 /* If X is a register that is being used as a pointer, see if we have
1105 a temporary slot we know it points to. To be consistent with
1106 the code below, we really should preserve all non-kept slots
1107 if we can't find a match, but that seems to be much too costly. */
1108 if (GET_CODE (x) == REG && REG_POINTER (x))
1109 p = find_temp_slot_from_address (x);
1111 /* If X is not in memory or is at a constant address, it cannot be in
1112 a temporary slot, but it can contain something whose address was
1114 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1116 for (p = temp_slots; p; p = p->next)
1117 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1123 /* First see if we can find a match. */
1125 p = find_temp_slot_from_address (XEXP (x, 0));
1129 /* Move everything at our level whose address was taken to our new
1130 level in case we used its address. */
1131 struct temp_slot *q;
1133 if (p->level == temp_slot_level)
1135 for (q = temp_slots; q; q = q->next)
1136 if (q != p && q->addr_taken && q->level == p->level)
1145 /* Otherwise, preserve all non-kept slots at this level. */
1146 for (p = temp_slots; p; p = p->next)
1147 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1151 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1152 with that RTL_EXPR, promote it into a temporary slot at the present
1153 level so it will not be freed when we free slots made in the
1157 preserve_rtl_expr_result (x)
1160 struct temp_slot *p;
1162 /* If X is not in memory or is at a constant address, it cannot be in
1163 a temporary slot. */
1164 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1167 /* If we can find a match, move it to our level unless it is already at
1169 p = find_temp_slot_from_address (XEXP (x, 0));
1172 p->level = MIN (p->level, temp_slot_level);
1179 /* Free all temporaries used so far. This is normally called at the end
1180 of generating code for a statement. Don't free any temporaries
1181 currently in use for an RTL_EXPR that hasn't yet been emitted.
1182 We could eventually do better than this since it can be reused while
1183 generating the same RTL_EXPR, but this is complex and probably not
1189 struct temp_slot *p;
1191 for (p = temp_slots; p; p = p->next)
1192 if (p->in_use && p->level == temp_slot_level && ! p->keep
1193 && p->rtl_expr == 0)
1196 combine_temp_slots ();
1199 /* Free all temporary slots used in T, an RTL_EXPR node. */
1202 free_temps_for_rtl_expr (t)
1205 struct temp_slot *p;
1207 for (p = temp_slots; p; p = p->next)
1208 if (p->rtl_expr == t)
1210 /* If this slot is below the current TEMP_SLOT_LEVEL, then it
1211 needs to be preserved. This can happen if a temporary in
1212 the RTL_EXPR was addressed; preserve_temp_slots will move
1213 the temporary into a higher level. */
1214 if (temp_slot_level <= p->level)
1217 p->rtl_expr = NULL_TREE;
1220 combine_temp_slots ();
1223 /* Mark all temporaries ever allocated in this function as not suitable
1224 for reuse until the current level is exited. */
1227 mark_all_temps_used ()
1229 struct temp_slot *p;
1231 for (p = temp_slots; p; p = p->next)
1233 p->in_use = p->keep = 1;
1234 p->level = MIN (p->level, temp_slot_level);
1238 /* Push deeper into the nesting level for stack temporaries. */
1246 /* Likewise, but save the new level as the place to allocate variables
1251 push_temp_slots_for_block ()
1255 var_temp_slot_level = temp_slot_level;
1258 /* Likewise, but save the new level as the place to allocate temporaries
1259 for TARGET_EXPRs. */
1262 push_temp_slots_for_target ()
1266 target_temp_slot_level = temp_slot_level;
1269 /* Set and get the value of target_temp_slot_level. The only
1270 permitted use of these functions is to save and restore this value. */
1273 get_target_temp_slot_level ()
1275 return target_temp_slot_level;
1279 set_target_temp_slot_level (level)
1282 target_temp_slot_level = level;
1286 /* Pop a temporary nesting level. All slots in use in the current level
1292 struct temp_slot *p;
1294 for (p = temp_slots; p; p = p->next)
1295 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1298 combine_temp_slots ();
1303 /* Initialize temporary slots. */
1308 /* We have not allocated any temporaries yet. */
1310 temp_slot_level = 0;
1311 var_temp_slot_level = 0;
1312 target_temp_slot_level = 0;
1315 /* Retroactively move an auto variable from a register to a stack slot.
1316 This is done when an address-reference to the variable is seen. */
1319 put_var_into_stack (decl)
1323 enum machine_mode promoted_mode, decl_mode;
1324 struct function *function = 0;
1326 int can_use_addressof;
1327 int volatilep = TREE_CODE (decl) != SAVE_EXPR && TREE_THIS_VOLATILE (decl);
1328 int usedp = (TREE_USED (decl)
1329 || (TREE_CODE (decl) != SAVE_EXPR && DECL_INITIAL (decl) != 0));
1331 context = decl_function_context (decl);
1333 /* Get the current rtl used for this object and its original mode. */
1334 reg = (TREE_CODE (decl) == SAVE_EXPR
1335 ? SAVE_EXPR_RTL (decl)
1336 : DECL_RTL_IF_SET (decl));
1338 /* No need to do anything if decl has no rtx yet
1339 since in that case caller is setting TREE_ADDRESSABLE
1340 and a stack slot will be assigned when the rtl is made. */
1344 /* Get the declared mode for this object. */
1345 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1346 : DECL_MODE (decl));
1347 /* Get the mode it's actually stored in. */
1348 promoted_mode = GET_MODE (reg);
1350 /* If this variable comes from an outer function,
1351 find that function's saved context. */
1352 if (context != current_function_decl && context != inline_function_decl)
1353 for (function = outer_function_chain; function; function = function->next)
1354 if (function->decl == context)
1357 /* If this is a variable-size object with a pseudo to address it,
1358 put that pseudo into the stack, if the var is nonlocal. */
1359 if (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl)
1360 && GET_CODE (reg) == MEM
1361 && GET_CODE (XEXP (reg, 0)) == REG
1362 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1364 reg = XEXP (reg, 0);
1365 decl_mode = promoted_mode = GET_MODE (reg);
1371 /* FIXME make it work for promoted modes too */
1372 && decl_mode == promoted_mode
1373 #ifdef NON_SAVING_SETJMP
1374 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1378 /* If we can't use ADDRESSOF, make sure we see through one we already
1380 if (! can_use_addressof && GET_CODE (reg) == MEM
1381 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1382 reg = XEXP (XEXP (reg, 0), 0);
1384 /* Now we should have a value that resides in one or more pseudo regs. */
1386 if (GET_CODE (reg) == REG)
1388 /* If this variable lives in the current function and we don't need
1389 to put things in the stack for the sake of setjmp, try to keep it
1390 in a register until we know we actually need the address. */
1391 if (can_use_addressof)
1392 gen_mem_addressof (reg, decl);
1394 put_reg_into_stack (function, reg, TREE_TYPE (decl), promoted_mode,
1395 decl_mode, volatilep, 0, usedp, 0);
1397 else if (GET_CODE (reg) == CONCAT)
1399 /* A CONCAT contains two pseudos; put them both in the stack.
1400 We do it so they end up consecutive.
1401 We fixup references to the parts only after we fixup references
1402 to the whole CONCAT, lest we do double fixups for the latter
1404 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1405 tree part_type = type_for_mode (part_mode, 0);
1406 rtx lopart = XEXP (reg, 0);
1407 rtx hipart = XEXP (reg, 1);
1408 #ifdef FRAME_GROWS_DOWNWARD
1409 /* Since part 0 should have a lower address, do it second. */
1410 put_reg_into_stack (function, hipart, part_type, part_mode,
1411 part_mode, volatilep, 0, 0, 0);
1412 put_reg_into_stack (function, lopart, part_type, part_mode,
1413 part_mode, volatilep, 0, 0, 0);
1415 put_reg_into_stack (function, lopart, part_type, part_mode,
1416 part_mode, volatilep, 0, 0, 0);
1417 put_reg_into_stack (function, hipart, part_type, part_mode,
1418 part_mode, volatilep, 0, 0, 0);
1421 /* Change the CONCAT into a combined MEM for both parts. */
1422 PUT_CODE (reg, MEM);
1424 /* set_mem_attributes uses DECL_RTL to avoid re-generating of
1425 already computed alias sets. Here we want to re-generate. */
1427 SET_DECL_RTL (decl, NULL);
1428 set_mem_attributes (reg, decl, 1);
1430 SET_DECL_RTL (decl, reg);
1432 /* The two parts are in memory order already.
1433 Use the lower parts address as ours. */
1434 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1435 /* Prevent sharing of rtl that might lose. */
1436 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1437 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1440 schedule_fixup_var_refs (function, reg, TREE_TYPE (decl),
1442 schedule_fixup_var_refs (function, lopart, part_type, part_mode, 0);
1443 schedule_fixup_var_refs (function, hipart, part_type, part_mode, 0);
1449 if (current_function_check_memory_usage)
1450 emit_library_call (chkr_set_right_libfunc, LCT_CONST_MAKE_BLOCK, VOIDmode,
1451 3, XEXP (reg, 0), Pmode,
1452 GEN_INT (GET_MODE_SIZE (GET_MODE (reg))),
1453 TYPE_MODE (sizetype),
1454 GEN_INT (MEMORY_USE_RW),
1455 TYPE_MODE (integer_type_node));
1458 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1459 into the stack frame of FUNCTION (0 means the current function).
1460 DECL_MODE is the machine mode of the user-level data type.
1461 PROMOTED_MODE is the machine mode of the register.
1462 VOLATILE_P is nonzero if this is for a "volatile" decl.
1463 USED_P is nonzero if this reg might have already been used in an insn. */
1466 put_reg_into_stack (function, reg, type, promoted_mode, decl_mode, volatile_p,
1467 original_regno, used_p, ht)
1468 struct function *function;
1471 enum machine_mode promoted_mode, decl_mode;
1473 unsigned int original_regno;
1475 struct hash_table *ht;
1477 struct function *func = function ? function : cfun;
1479 unsigned int regno = original_regno;
1482 regno = REGNO (reg);
1484 if (regno < func->x_max_parm_reg)
1485 new = func->x_parm_reg_stack_loc[regno];
1488 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode), 0, func);
1490 PUT_CODE (reg, MEM);
1491 PUT_MODE (reg, decl_mode);
1492 XEXP (reg, 0) = XEXP (new, 0);
1493 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1494 MEM_VOLATILE_P (reg) = volatile_p;
1496 /* If this is a memory ref that contains aggregate components,
1497 mark it as such for cse and loop optimize. If we are reusing a
1498 previously generated stack slot, then we need to copy the bit in
1499 case it was set for other reasons. For instance, it is set for
1500 __builtin_va_alist. */
1503 MEM_SET_IN_STRUCT_P (reg,
1504 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1505 set_mem_alias_set (reg, get_alias_set (type));
1508 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht);
1511 /* Make sure that all refs to the variable, previously made
1512 when it was a register, are fixed up to be valid again.
1513 See function above for meaning of arguments. */
1516 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht)
1517 struct function *function;
1520 enum machine_mode promoted_mode;
1521 struct hash_table *ht;
1523 int unsigned_p = type ? TREE_UNSIGNED (type) : 0;
1527 struct var_refs_queue *temp;
1530 = (struct var_refs_queue *) xmalloc (sizeof (struct var_refs_queue));
1531 temp->modified = reg;
1532 temp->promoted_mode = promoted_mode;
1533 temp->unsignedp = unsigned_p;
1534 temp->next = function->fixup_var_refs_queue;
1535 function->fixup_var_refs_queue = temp;
1538 /* Variable is local; fix it up now. */
1539 fixup_var_refs (reg, promoted_mode, unsigned_p, ht);
1543 fixup_var_refs (var, promoted_mode, unsignedp, ht)
1545 enum machine_mode promoted_mode;
1547 struct hash_table *ht;
1550 rtx first_insn = get_insns ();
1551 struct sequence_stack *stack = seq_stack;
1552 tree rtl_exps = rtl_expr_chain;
1554 /* If there's a hash table, it must record all uses of VAR. */
1559 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp);
1563 fixup_var_refs_insns (first_insn, var, promoted_mode, unsignedp,
1566 /* Scan all pending sequences too. */
1567 for (; stack; stack = stack->next)
1569 push_to_full_sequence (stack->first, stack->last);
1570 fixup_var_refs_insns (stack->first, var, promoted_mode, unsignedp,
1572 /* Update remembered end of sequence
1573 in case we added an insn at the end. */
1574 stack->last = get_last_insn ();
1578 /* Scan all waiting RTL_EXPRs too. */
1579 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1581 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1582 if (seq != const0_rtx && seq != 0)
1584 push_to_sequence (seq);
1585 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0);
1591 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1592 some part of an insn. Return a struct fixup_replacement whose OLD
1593 value is equal to X. Allocate a new structure if no such entry exists. */
1595 static struct fixup_replacement *
1596 find_fixup_replacement (replacements, x)
1597 struct fixup_replacement **replacements;
1600 struct fixup_replacement *p;
1602 /* See if we have already replaced this. */
1603 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1608 p = (struct fixup_replacement *) xmalloc (sizeof (struct fixup_replacement));
1611 p->next = *replacements;
1618 /* Scan the insn-chain starting with INSN for refs to VAR
1619 and fix them up. TOPLEVEL is nonzero if this chain is the
1620 main chain of insns for the current function. */
1623 fixup_var_refs_insns (insn, var, promoted_mode, unsignedp, toplevel)
1626 enum machine_mode promoted_mode;
1632 /* fixup_var_refs_insn might modify insn, so save its next
1634 rtx next = NEXT_INSN (insn);
1636 /* CALL_PLACEHOLDERs are special; we have to switch into each of
1637 the three sequences they (potentially) contain, and process
1638 them recursively. The CALL_INSN itself is not interesting. */
1640 if (GET_CODE (insn) == CALL_INSN
1641 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
1645 /* Look at the Normal call, sibling call and tail recursion
1646 sequences attached to the CALL_PLACEHOLDER. */
1647 for (i = 0; i < 3; i++)
1649 rtx seq = XEXP (PATTERN (insn), i);
1652 push_to_sequence (seq);
1653 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0);
1654 XEXP (PATTERN (insn), i) = get_insns ();
1660 else if (INSN_P (insn))
1661 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel);
1667 /* Look up the insns which reference VAR in HT and fix them up. Other
1668 arguments are the same as fixup_var_refs_insns.
1670 N.B. No need for special processing of CALL_PLACEHOLDERs here,
1671 because the hash table will point straight to the interesting insn
1672 (inside the CALL_PLACEHOLDER). */
1674 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp)
1675 struct hash_table *ht;
1677 enum machine_mode promoted_mode;
1680 struct insns_for_mem_entry *ime = (struct insns_for_mem_entry *)
1681 hash_lookup (ht, var, /*create=*/0, /*copy=*/0);
1682 rtx insn_list = ime->insns;
1686 rtx insn = XEXP (insn_list, 0);
1689 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, 1);
1691 insn_list = XEXP (insn_list, 1);
1696 /* Per-insn processing by fixup_var_refs_insns(_with_hash). INSN is
1697 the insn under examination, VAR is the variable to fix up
1698 references to, PROMOTED_MODE and UNSIGNEDP describe VAR, and
1699 TOPLEVEL is nonzero if this is the main insn chain for this
1702 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel)
1705 enum machine_mode promoted_mode;
1710 rtx set, prev, prev_set;
1713 /* Remember the notes in case we delete the insn. */
1714 note = REG_NOTES (insn);
1716 /* If this is a CLOBBER of VAR, delete it.
1718 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1719 and REG_RETVAL notes too. */
1720 if (GET_CODE (PATTERN (insn)) == CLOBBER
1721 && (XEXP (PATTERN (insn), 0) == var
1722 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1723 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1724 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1726 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1727 /* The REG_LIBCALL note will go away since we are going to
1728 turn INSN into a NOTE, so just delete the
1729 corresponding REG_RETVAL note. */
1730 remove_note (XEXP (note, 0),
1731 find_reg_note (XEXP (note, 0), REG_RETVAL,
1734 /* In unoptimized compilation, we shouldn't call delete_insn
1735 except in jump.c doing warnings. */
1736 PUT_CODE (insn, NOTE);
1737 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1738 NOTE_SOURCE_FILE (insn) = 0;
1741 /* The insn to load VAR from a home in the arglist
1742 is now a no-op. When we see it, just delete it.
1743 Similarly if this is storing VAR from a register from which
1744 it was loaded in the previous insn. This will occur
1745 when an ADDRESSOF was made for an arglist slot. */
1747 && (set = single_set (insn)) != 0
1748 && SET_DEST (set) == var
1749 /* If this represents the result of an insn group,
1750 don't delete the insn. */
1751 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1752 && (rtx_equal_p (SET_SRC (set), var)
1753 || (GET_CODE (SET_SRC (set)) == REG
1754 && (prev = prev_nonnote_insn (insn)) != 0
1755 && (prev_set = single_set (prev)) != 0
1756 && SET_DEST (prev_set) == SET_SRC (set)
1757 && rtx_equal_p (SET_SRC (prev_set), var))))
1759 /* In unoptimized compilation, we shouldn't call delete_insn
1760 except in jump.c doing warnings. */
1761 PUT_CODE (insn, NOTE);
1762 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1763 NOTE_SOURCE_FILE (insn) = 0;
1767 struct fixup_replacement *replacements = 0;
1768 rtx next_insn = NEXT_INSN (insn);
1770 if (SMALL_REGISTER_CLASSES)
1772 /* If the insn that copies the results of a CALL_INSN
1773 into a pseudo now references VAR, we have to use an
1774 intermediate pseudo since we want the life of the
1775 return value register to be only a single insn.
1777 If we don't use an intermediate pseudo, such things as
1778 address computations to make the address of VAR valid
1779 if it is not can be placed between the CALL_INSN and INSN.
1781 To make sure this doesn't happen, we record the destination
1782 of the CALL_INSN and see if the next insn uses both that
1785 if (call_dest != 0 && GET_CODE (insn) == INSN
1786 && reg_mentioned_p (var, PATTERN (insn))
1787 && reg_mentioned_p (call_dest, PATTERN (insn)))
1789 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1791 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1793 PATTERN (insn) = replace_rtx (PATTERN (insn),
1797 if (GET_CODE (insn) == CALL_INSN
1798 && GET_CODE (PATTERN (insn)) == SET)
1799 call_dest = SET_DEST (PATTERN (insn));
1800 else if (GET_CODE (insn) == CALL_INSN
1801 && GET_CODE (PATTERN (insn)) == PARALLEL
1802 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1803 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1808 /* See if we have to do anything to INSN now that VAR is in
1809 memory. If it needs to be loaded into a pseudo, use a single
1810 pseudo for the entire insn in case there is a MATCH_DUP
1811 between two operands. We pass a pointer to the head of
1812 a list of struct fixup_replacements. If fixup_var_refs_1
1813 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1814 it will record them in this list.
1816 If it allocated a pseudo for any replacement, we copy into
1819 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1822 /* If this is last_parm_insn, and any instructions were output
1823 after it to fix it up, then we must set last_parm_insn to
1824 the last such instruction emitted. */
1825 if (insn == last_parm_insn)
1826 last_parm_insn = PREV_INSN (next_insn);
1828 while (replacements)
1830 struct fixup_replacement *next;
1832 if (GET_CODE (replacements->new) == REG)
1837 /* OLD might be a (subreg (mem)). */
1838 if (GET_CODE (replacements->old) == SUBREG)
1840 = fixup_memory_subreg (replacements->old, insn, 0);
1843 = fixup_stack_1 (replacements->old, insn);
1845 insert_before = insn;
1847 /* If we are changing the mode, do a conversion.
1848 This might be wasteful, but combine.c will
1849 eliminate much of the waste. */
1851 if (GET_MODE (replacements->new)
1852 != GET_MODE (replacements->old))
1855 convert_move (replacements->new,
1856 replacements->old, unsignedp);
1857 seq = gen_sequence ();
1861 seq = gen_move_insn (replacements->new,
1864 emit_insn_before (seq, insert_before);
1867 next = replacements->next;
1868 free (replacements);
1869 replacements = next;
1873 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1874 But don't touch other insns referred to by reg-notes;
1875 we will get them elsewhere. */
1878 if (GET_CODE (note) != INSN_LIST)
1880 = walk_fixup_memory_subreg (XEXP (note, 0), insn, 1);
1881 note = XEXP (note, 1);
1885 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1886 See if the rtx expression at *LOC in INSN needs to be changed.
1888 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1889 contain a list of original rtx's and replacements. If we find that we need
1890 to modify this insn by replacing a memory reference with a pseudo or by
1891 making a new MEM to implement a SUBREG, we consult that list to see if
1892 we have already chosen a replacement. If none has already been allocated,
1893 we allocate it and update the list. fixup_var_refs_insn will copy VAR
1894 or the SUBREG, as appropriate, to the pseudo. */
1897 fixup_var_refs_1 (var, promoted_mode, loc, insn, replacements)
1899 enum machine_mode promoted_mode;
1902 struct fixup_replacement **replacements;
1905 register rtx x = *loc;
1906 RTX_CODE code = GET_CODE (x);
1907 register const char *fmt;
1908 register rtx tem, tem1;
1909 struct fixup_replacement *replacement;
1914 if (XEXP (x, 0) == var)
1916 /* Prevent sharing of rtl that might lose. */
1917 rtx sub = copy_rtx (XEXP (var, 0));
1919 if (! validate_change (insn, loc, sub, 0))
1921 rtx y = gen_reg_rtx (GET_MODE (sub));
1924 /* We should be able to replace with a register or all is lost.
1925 Note that we can't use validate_change to verify this, since
1926 we're not caring for replacing all dups simultaneously. */
1927 if (! validate_replace_rtx (*loc, y, insn))
1930 /* Careful! First try to recognize a direct move of the
1931 value, mimicking how things are done in gen_reload wrt
1932 PLUS. Consider what happens when insn is a conditional
1933 move instruction and addsi3 clobbers flags. */
1936 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1937 seq = gen_sequence ();
1940 if (recog_memoized (new_insn) < 0)
1942 /* That failed. Fall back on force_operand and hope. */
1945 sub = force_operand (sub, y);
1947 emit_insn (gen_move_insn (y, sub));
1948 seq = gen_sequence ();
1953 /* Don't separate setter from user. */
1954 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1955 insn = PREV_INSN (insn);
1958 emit_insn_before (seq, insn);
1966 /* If we already have a replacement, use it. Otherwise,
1967 try to fix up this address in case it is invalid. */
1969 replacement = find_fixup_replacement (replacements, var);
1970 if (replacement->new)
1972 *loc = replacement->new;
1976 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1978 /* Unless we are forcing memory to register or we changed the mode,
1979 we can leave things the way they are if the insn is valid. */
1981 INSN_CODE (insn) = -1;
1982 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1983 && recog_memoized (insn) >= 0)
1986 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1990 /* If X contains VAR, we need to unshare it here so that we update
1991 each occurrence separately. But all identical MEMs in one insn
1992 must be replaced with the same rtx because of the possibility of
1995 if (reg_mentioned_p (var, x))
1997 replacement = find_fixup_replacement (replacements, x);
1998 if (replacement->new == 0)
1999 replacement->new = copy_most_rtx (x, var);
2001 *loc = x = replacement->new;
2002 code = GET_CODE (x);
2018 /* Note that in some cases those types of expressions are altered
2019 by optimize_bit_field, and do not survive to get here. */
2020 if (XEXP (x, 0) == var
2021 || (GET_CODE (XEXP (x, 0)) == SUBREG
2022 && SUBREG_REG (XEXP (x, 0)) == var))
2024 /* Get TEM as a valid MEM in the mode presently in the insn.
2026 We don't worry about the possibility of MATCH_DUP here; it
2027 is highly unlikely and would be tricky to handle. */
2030 if (GET_CODE (tem) == SUBREG)
2032 if (GET_MODE_BITSIZE (GET_MODE (tem))
2033 > GET_MODE_BITSIZE (GET_MODE (var)))
2035 replacement = find_fixup_replacement (replacements, var);
2036 if (replacement->new == 0)
2037 replacement->new = gen_reg_rtx (GET_MODE (var));
2038 SUBREG_REG (tem) = replacement->new;
2040 /* The following code works only if we have a MEM, so we
2041 need to handle the subreg here. We directly substitute
2042 it assuming that a subreg must be OK here. We already
2043 scheduled a replacement to copy the mem into the
2049 tem = fixup_memory_subreg (tem, insn, 0);
2052 tem = fixup_stack_1 (tem, insn);
2054 /* Unless we want to load from memory, get TEM into the proper mode
2055 for an extract from memory. This can only be done if the
2056 extract is at a constant position and length. */
2058 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
2059 && GET_CODE (XEXP (x, 2)) == CONST_INT
2060 && ! mode_dependent_address_p (XEXP (tem, 0))
2061 && ! MEM_VOLATILE_P (tem))
2063 enum machine_mode wanted_mode = VOIDmode;
2064 enum machine_mode is_mode = GET_MODE (tem);
2065 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
2068 if (GET_CODE (x) == ZERO_EXTRACT)
2071 = insn_data[(int) CODE_FOR_extzv].operand[1].mode;
2072 if (wanted_mode == VOIDmode)
2073 wanted_mode = word_mode;
2077 if (GET_CODE (x) == SIGN_EXTRACT)
2079 wanted_mode = insn_data[(int) CODE_FOR_extv].operand[1].mode;
2080 if (wanted_mode == VOIDmode)
2081 wanted_mode = word_mode;
2084 /* If we have a narrower mode, we can do something. */
2085 if (wanted_mode != VOIDmode
2086 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2088 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2089 rtx old_pos = XEXP (x, 2);
2092 /* If the bytes and bits are counted differently, we
2093 must adjust the offset. */
2094 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2095 offset = (GET_MODE_SIZE (is_mode)
2096 - GET_MODE_SIZE (wanted_mode) - offset);
2098 pos %= GET_MODE_BITSIZE (wanted_mode);
2100 newmem = adjust_address_nv (tem, wanted_mode, offset);
2102 /* Make the change and see if the insn remains valid. */
2103 INSN_CODE (insn) = -1;
2104 XEXP (x, 0) = newmem;
2105 XEXP (x, 2) = GEN_INT (pos);
2107 if (recog_memoized (insn) >= 0)
2110 /* Otherwise, restore old position. XEXP (x, 0) will be
2112 XEXP (x, 2) = old_pos;
2116 /* If we get here, the bitfield extract insn can't accept a memory
2117 reference. Copy the input into a register. */
2119 tem1 = gen_reg_rtx (GET_MODE (tem));
2120 emit_insn_before (gen_move_insn (tem1, tem), insn);
2127 if (SUBREG_REG (x) == var)
2129 /* If this is a special SUBREG made because VAR was promoted
2130 from a wider mode, replace it with VAR and call ourself
2131 recursively, this time saying that the object previously
2132 had its current mode (by virtue of the SUBREG). */
2134 if (SUBREG_PROMOTED_VAR_P (x))
2137 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements);
2141 /* If this SUBREG makes VAR wider, it has become a paradoxical
2142 SUBREG with VAR in memory, but these aren't allowed at this
2143 stage of the compilation. So load VAR into a pseudo and take
2144 a SUBREG of that pseudo. */
2145 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2147 replacement = find_fixup_replacement (replacements, var);
2148 if (replacement->new == 0)
2149 replacement->new = gen_reg_rtx (promoted_mode);
2150 SUBREG_REG (x) = replacement->new;
2154 /* See if we have already found a replacement for this SUBREG.
2155 If so, use it. Otherwise, make a MEM and see if the insn
2156 is recognized. If not, or if we should force MEM into a register,
2157 make a pseudo for this SUBREG. */
2158 replacement = find_fixup_replacement (replacements, x);
2159 if (replacement->new)
2161 *loc = replacement->new;
2165 replacement->new = *loc = fixup_memory_subreg (x, insn, 0);
2167 INSN_CODE (insn) = -1;
2168 if (! flag_force_mem && recog_memoized (insn) >= 0)
2171 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2177 /* First do special simplification of bit-field references. */
2178 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2179 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2180 optimize_bit_field (x, insn, 0);
2181 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2182 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2183 optimize_bit_field (x, insn, 0);
2185 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2186 into a register and then store it back out. */
2187 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2188 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2189 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2190 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2191 > GET_MODE_SIZE (GET_MODE (var))))
2193 replacement = find_fixup_replacement (replacements, var);
2194 if (replacement->new == 0)
2195 replacement->new = gen_reg_rtx (GET_MODE (var));
2197 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2198 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2201 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2202 insn into a pseudo and store the low part of the pseudo into VAR. */
2203 if (GET_CODE (SET_DEST (x)) == SUBREG
2204 && SUBREG_REG (SET_DEST (x)) == var
2205 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2206 > GET_MODE_SIZE (GET_MODE (var))))
2208 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2209 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2216 rtx dest = SET_DEST (x);
2217 rtx src = SET_SRC (x);
2219 rtx outerdest = dest;
2222 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2223 || GET_CODE (dest) == SIGN_EXTRACT
2224 || GET_CODE (dest) == ZERO_EXTRACT)
2225 dest = XEXP (dest, 0);
2227 if (GET_CODE (src) == SUBREG)
2228 src = SUBREG_REG (src);
2230 /* If VAR does not appear at the top level of the SET
2231 just scan the lower levels of the tree. */
2233 if (src != var && dest != var)
2236 /* We will need to rerecognize this insn. */
2237 INSN_CODE (insn) = -1;
2240 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var)
2242 /* Since this case will return, ensure we fixup all the
2244 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2245 insn, replacements);
2246 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2247 insn, replacements);
2248 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2249 insn, replacements);
2251 tem = XEXP (outerdest, 0);
2253 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2254 that may appear inside a ZERO_EXTRACT.
2255 This was legitimate when the MEM was a REG. */
2256 if (GET_CODE (tem) == SUBREG
2257 && SUBREG_REG (tem) == var)
2258 tem = fixup_memory_subreg (tem, insn, 0);
2260 tem = fixup_stack_1 (tem, insn);
2262 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2263 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2264 && ! mode_dependent_address_p (XEXP (tem, 0))
2265 && ! MEM_VOLATILE_P (tem))
2267 enum machine_mode wanted_mode;
2268 enum machine_mode is_mode = GET_MODE (tem);
2269 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2271 wanted_mode = insn_data[(int) CODE_FOR_insv].operand[0].mode;
2272 if (wanted_mode == VOIDmode)
2273 wanted_mode = word_mode;
2275 /* If we have a narrower mode, we can do something. */
2276 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2278 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2279 rtx old_pos = XEXP (outerdest, 2);
2282 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2283 offset = (GET_MODE_SIZE (is_mode)
2284 - GET_MODE_SIZE (wanted_mode) - offset);
2286 pos %= GET_MODE_BITSIZE (wanted_mode);
2288 newmem = adjust_address_nv (tem, wanted_mode, offset);
2290 /* Make the change and see if the insn remains valid. */
2291 INSN_CODE (insn) = -1;
2292 XEXP (outerdest, 0) = newmem;
2293 XEXP (outerdest, 2) = GEN_INT (pos);
2295 if (recog_memoized (insn) >= 0)
2298 /* Otherwise, restore old position. XEXP (x, 0) will be
2300 XEXP (outerdest, 2) = old_pos;
2304 /* If we get here, the bit-field store doesn't allow memory
2305 or isn't located at a constant position. Load the value into
2306 a register, do the store, and put it back into memory. */
2308 tem1 = gen_reg_rtx (GET_MODE (tem));
2309 emit_insn_before (gen_move_insn (tem1, tem), insn);
2310 emit_insn_after (gen_move_insn (tem, tem1), insn);
2311 XEXP (outerdest, 0) = tem1;
2316 /* STRICT_LOW_PART is a no-op on memory references
2317 and it can cause combinations to be unrecognizable,
2320 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2321 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2323 /* A valid insn to copy VAR into or out of a register
2324 must be left alone, to avoid an infinite loop here.
2325 If the reference to VAR is by a subreg, fix that up,
2326 since SUBREG is not valid for a memref.
2327 Also fix up the address of the stack slot.
2329 Note that we must not try to recognize the insn until
2330 after we know that we have valid addresses and no
2331 (subreg (mem ...) ...) constructs, since these interfere
2332 with determining the validity of the insn. */
2334 if ((SET_SRC (x) == var
2335 || (GET_CODE (SET_SRC (x)) == SUBREG
2336 && SUBREG_REG (SET_SRC (x)) == var))
2337 && (GET_CODE (SET_DEST (x)) == REG
2338 || (GET_CODE (SET_DEST (x)) == SUBREG
2339 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2340 && GET_MODE (var) == promoted_mode
2341 && x == single_set (insn))
2345 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2346 if (replacement->new)
2347 SET_SRC (x) = replacement->new;
2348 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2349 SET_SRC (x) = replacement->new
2350 = fixup_memory_subreg (SET_SRC (x), insn, 0);
2352 SET_SRC (x) = replacement->new
2353 = fixup_stack_1 (SET_SRC (x), insn);
2355 if (recog_memoized (insn) >= 0)
2358 /* INSN is not valid, but we know that we want to
2359 copy SET_SRC (x) to SET_DEST (x) in some way. So
2360 we generate the move and see whether it requires more
2361 than one insn. If it does, we emit those insns and
2362 delete INSN. Otherwise, we an just replace the pattern
2363 of INSN; we have already verified above that INSN has
2364 no other function that to do X. */
2366 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2367 if (GET_CODE (pat) == SEQUENCE)
2369 last = emit_insn_before (pat, insn);
2371 /* INSN might have REG_RETVAL or other important notes, so
2372 we need to store the pattern of the last insn in the
2373 sequence into INSN similarly to the normal case. LAST
2374 should not have REG_NOTES, but we allow them if INSN has
2376 if (REG_NOTES (last) && REG_NOTES (insn))
2378 if (REG_NOTES (last))
2379 REG_NOTES (insn) = REG_NOTES (last);
2380 PATTERN (insn) = PATTERN (last);
2382 PUT_CODE (last, NOTE);
2383 NOTE_LINE_NUMBER (last) = NOTE_INSN_DELETED;
2384 NOTE_SOURCE_FILE (last) = 0;
2387 PATTERN (insn) = pat;
2392 if ((SET_DEST (x) == var
2393 || (GET_CODE (SET_DEST (x)) == SUBREG
2394 && SUBREG_REG (SET_DEST (x)) == var))
2395 && (GET_CODE (SET_SRC (x)) == REG
2396 || (GET_CODE (SET_SRC (x)) == SUBREG
2397 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2398 && GET_MODE (var) == promoted_mode
2399 && x == single_set (insn))
2403 if (GET_CODE (SET_DEST (x)) == SUBREG)
2404 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn, 0);
2406 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2408 if (recog_memoized (insn) >= 0)
2411 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2412 if (GET_CODE (pat) == SEQUENCE)
2414 last = emit_insn_before (pat, insn);
2416 /* INSN might have REG_RETVAL or other important notes, so
2417 we need to store the pattern of the last insn in the
2418 sequence into INSN similarly to the normal case. LAST
2419 should not have REG_NOTES, but we allow them if INSN has
2421 if (REG_NOTES (last) && REG_NOTES (insn))
2423 if (REG_NOTES (last))
2424 REG_NOTES (insn) = REG_NOTES (last);
2425 PATTERN (insn) = PATTERN (last);
2427 PUT_CODE (last, NOTE);
2428 NOTE_LINE_NUMBER (last) = NOTE_INSN_DELETED;
2429 NOTE_SOURCE_FILE (last) = 0;
2432 PATTERN (insn) = pat;
2437 /* Otherwise, storing into VAR must be handled specially
2438 by storing into a temporary and copying that into VAR
2439 with a new insn after this one. Note that this case
2440 will be used when storing into a promoted scalar since
2441 the insn will now have different modes on the input
2442 and output and hence will be invalid (except for the case
2443 of setting it to a constant, which does not need any
2444 change if it is valid). We generate extra code in that case,
2445 but combine.c will eliminate it. */
2450 rtx fixeddest = SET_DEST (x);
2452 /* STRICT_LOW_PART can be discarded, around a MEM. */
2453 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2454 fixeddest = XEXP (fixeddest, 0);
2455 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2456 if (GET_CODE (fixeddest) == SUBREG)
2458 fixeddest = fixup_memory_subreg (fixeddest, insn, 0);
2459 promoted_mode = GET_MODE (fixeddest);
2462 fixeddest = fixup_stack_1 (fixeddest, insn);
2464 temp = gen_reg_rtx (promoted_mode);
2466 emit_insn_after (gen_move_insn (fixeddest,
2467 gen_lowpart (GET_MODE (fixeddest),
2471 SET_DEST (x) = temp;
2479 /* Nothing special about this RTX; fix its operands. */
2481 fmt = GET_RTX_FORMAT (code);
2482 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2485 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements);
2486 else if (fmt[i] == 'E')
2489 for (j = 0; j < XVECLEN (x, i); j++)
2490 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2491 insn, replacements);
2496 /* Given X, an rtx of the form (SUBREG:m1 (MEM:m2 addr)),
2497 return an rtx (MEM:m1 newaddr) which is equivalent.
2498 If any insns must be emitted to compute NEWADDR, put them before INSN.
2500 UNCRITICAL nonzero means accept paradoxical subregs.
2501 This is used for subregs found inside REG_NOTES. */
2504 fixup_memory_subreg (x, insn, uncritical)
2509 int offset = SUBREG_BYTE (x);
2510 rtx addr = XEXP (SUBREG_REG (x), 0);
2511 enum machine_mode mode = GET_MODE (x);
2514 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2515 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))
2519 if (!flag_force_addr
2520 && memory_address_p (mode, plus_constant (addr, offset)))
2521 /* Shortcut if no insns need be emitted. */
2522 return adjust_address (SUBREG_REG (x), mode, offset);
2525 result = adjust_address (SUBREG_REG (x), mode, offset);
2526 emit_insn_before (gen_sequence (), insn);
2531 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2532 Replace subexpressions of X in place.
2533 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2534 Otherwise return X, with its contents possibly altered.
2536 If any insns must be emitted to compute NEWADDR, put them before INSN.
2538 UNCRITICAL is as in fixup_memory_subreg. */
2541 walk_fixup_memory_subreg (x, insn, uncritical)
2546 register enum rtx_code code;
2547 register const char *fmt;
2553 code = GET_CODE (x);
2555 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2556 return fixup_memory_subreg (x, insn, uncritical);
2558 /* Nothing special about this RTX; fix its operands. */
2560 fmt = GET_RTX_FORMAT (code);
2561 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2564 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn, uncritical);
2565 else if (fmt[i] == 'E')
2568 for (j = 0; j < XVECLEN (x, i); j++)
2570 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn, uncritical);
2576 /* For each memory ref within X, if it refers to a stack slot
2577 with an out of range displacement, put the address in a temp register
2578 (emitting new insns before INSN to load these registers)
2579 and alter the memory ref to use that register.
2580 Replace each such MEM rtx with a copy, to avoid clobberage. */
2583 fixup_stack_1 (x, insn)
2588 register RTX_CODE code = GET_CODE (x);
2589 register const char *fmt;
2593 register rtx ad = XEXP (x, 0);
2594 /* If we have address of a stack slot but it's not valid
2595 (displacement is too large), compute the sum in a register. */
2596 if (GET_CODE (ad) == PLUS
2597 && GET_CODE (XEXP (ad, 0)) == REG
2598 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2599 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2600 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2601 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2602 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2604 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2605 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2606 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2607 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2610 if (memory_address_p (GET_MODE (x), ad))
2614 temp = copy_to_reg (ad);
2615 seq = gen_sequence ();
2617 emit_insn_before (seq, insn);
2618 return replace_equiv_address (x, temp);
2623 fmt = GET_RTX_FORMAT (code);
2624 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2627 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2628 else if (fmt[i] == 'E')
2631 for (j = 0; j < XVECLEN (x, i); j++)
2632 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2638 /* Optimization: a bit-field instruction whose field
2639 happens to be a byte or halfword in memory
2640 can be changed to a move instruction.
2642 We call here when INSN is an insn to examine or store into a bit-field.
2643 BODY is the SET-rtx to be altered.
2645 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2646 (Currently this is called only from function.c, and EQUIV_MEM
2650 optimize_bit_field (body, insn, equiv_mem)
2655 register rtx bitfield;
2658 enum machine_mode mode;
2660 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2661 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2662 bitfield = SET_DEST (body), destflag = 1;
2664 bitfield = SET_SRC (body), destflag = 0;
2666 /* First check that the field being stored has constant size and position
2667 and is in fact a byte or halfword suitably aligned. */
2669 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2670 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2671 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2673 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2675 register rtx memref = 0;
2677 /* Now check that the containing word is memory, not a register,
2678 and that it is safe to change the machine mode. */
2680 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2681 memref = XEXP (bitfield, 0);
2682 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2684 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2685 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2686 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2687 memref = SUBREG_REG (XEXP (bitfield, 0));
2688 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2690 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2691 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2694 && ! mode_dependent_address_p (XEXP (memref, 0))
2695 && ! MEM_VOLATILE_P (memref))
2697 /* Now adjust the address, first for any subreg'ing
2698 that we are now getting rid of,
2699 and then for which byte of the word is wanted. */
2701 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2704 /* Adjust OFFSET to count bits from low-address byte. */
2705 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2706 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2707 - offset - INTVAL (XEXP (bitfield, 1)));
2709 /* Adjust OFFSET to count bytes from low-address byte. */
2710 offset /= BITS_PER_UNIT;
2711 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2713 offset += (SUBREG_BYTE (XEXP (bitfield, 0))
2714 / UNITS_PER_WORD) * UNITS_PER_WORD;
2715 if (BYTES_BIG_ENDIAN)
2716 offset -= (MIN (UNITS_PER_WORD,
2717 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2718 - MIN (UNITS_PER_WORD,
2719 GET_MODE_SIZE (GET_MODE (memref))));
2723 memref = adjust_address (memref, mode, offset);
2724 insns = get_insns ();
2726 emit_insns_before (insns, insn);
2728 /* Store this memory reference where
2729 we found the bit field reference. */
2733 validate_change (insn, &SET_DEST (body), memref, 1);
2734 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2736 rtx src = SET_SRC (body);
2737 while (GET_CODE (src) == SUBREG
2738 && SUBREG_BYTE (src) == 0)
2739 src = SUBREG_REG (src);
2740 if (GET_MODE (src) != GET_MODE (memref))
2741 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2742 validate_change (insn, &SET_SRC (body), src, 1);
2744 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2745 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2746 /* This shouldn't happen because anything that didn't have
2747 one of these modes should have got converted explicitly
2748 and then referenced through a subreg.
2749 This is so because the original bit-field was
2750 handled by agg_mode and so its tree structure had
2751 the same mode that memref now has. */
2756 rtx dest = SET_DEST (body);
2758 while (GET_CODE (dest) == SUBREG
2759 && SUBREG_BYTE (dest) == 0
2760 && (GET_MODE_CLASS (GET_MODE (dest))
2761 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2762 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2764 dest = SUBREG_REG (dest);
2766 validate_change (insn, &SET_DEST (body), dest, 1);
2768 if (GET_MODE (dest) == GET_MODE (memref))
2769 validate_change (insn, &SET_SRC (body), memref, 1);
2772 /* Convert the mem ref to the destination mode. */
2773 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2776 convert_move (newreg, memref,
2777 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2781 validate_change (insn, &SET_SRC (body), newreg, 1);
2785 /* See if we can convert this extraction or insertion into
2786 a simple move insn. We might not be able to do so if this
2787 was, for example, part of a PARALLEL.
2789 If we succeed, write out any needed conversions. If we fail,
2790 it is hard to guess why we failed, so don't do anything
2791 special; just let the optimization be suppressed. */
2793 if (apply_change_group () && seq)
2794 emit_insns_before (seq, insn);
2799 /* These routines are responsible for converting virtual register references
2800 to the actual hard register references once RTL generation is complete.
2802 The following four variables are used for communication between the
2803 routines. They contain the offsets of the virtual registers from their
2804 respective hard registers. */
2806 static int in_arg_offset;
2807 static int var_offset;
2808 static int dynamic_offset;
2809 static int out_arg_offset;
2810 static int cfa_offset;
2812 /* In most machines, the stack pointer register is equivalent to the bottom
2815 #ifndef STACK_POINTER_OFFSET
2816 #define STACK_POINTER_OFFSET 0
2819 /* If not defined, pick an appropriate default for the offset of dynamically
2820 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2821 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2823 #ifndef STACK_DYNAMIC_OFFSET
2825 /* The bottom of the stack points to the actual arguments. If
2826 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2827 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2828 stack space for register parameters is not pushed by the caller, but
2829 rather part of the fixed stack areas and hence not included in
2830 `current_function_outgoing_args_size'. Nevertheless, we must allow
2831 for it when allocating stack dynamic objects. */
2833 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2834 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2835 ((ACCUMULATE_OUTGOING_ARGS \
2836 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2837 + (STACK_POINTER_OFFSET)) \
2840 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2841 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2842 + (STACK_POINTER_OFFSET))
2846 /* On most machines, the CFA coincides with the first incoming parm. */
2848 #ifndef ARG_POINTER_CFA_OFFSET
2849 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2852 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just had
2853 its address taken. DECL is the decl for the object stored in the
2854 register, for later use if we do need to force REG into the stack.
2855 REG is overwritten by the MEM like in put_reg_into_stack. */
2858 gen_mem_addressof (reg, decl)
2862 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2865 /* Calculate this before we start messing with decl's RTL. */
2866 HOST_WIDE_INT set = get_alias_set (decl);
2868 /* If the original REG was a user-variable, then so is the REG whose
2869 address is being taken. Likewise for unchanging. */
2870 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2871 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2873 PUT_CODE (reg, MEM);
2877 tree type = TREE_TYPE (decl);
2878 enum machine_mode decl_mode
2879 = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
2880 : DECL_MODE (decl));
2882 PUT_MODE (reg, decl_mode);
2883 MEM_VOLATILE_P (reg) = TREE_SIDE_EFFECTS (decl);
2884 MEM_SET_IN_STRUCT_P (reg, AGGREGATE_TYPE_P (type));
2885 set_mem_alias_set (reg, set);
2887 if (TREE_USED (decl) || DECL_INITIAL (decl) != 0)
2888 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), 0);
2892 /* We have no alias information about this newly created MEM. */
2893 set_mem_alias_set (reg, 0);
2895 fixup_var_refs (reg, GET_MODE (reg), 0, 0);
2901 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2904 flush_addressof (decl)
2907 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2908 && DECL_RTL (decl) != 0
2909 && GET_CODE (DECL_RTL (decl)) == MEM
2910 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2911 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2912 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2915 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2918 put_addressof_into_stack (r, ht)
2920 struct hash_table *ht;
2923 int volatile_p, used_p;
2925 rtx reg = XEXP (r, 0);
2927 if (GET_CODE (reg) != REG)
2930 decl = ADDRESSOF_DECL (r);
2933 type = TREE_TYPE (decl);
2934 volatile_p = (TREE_CODE (decl) != SAVE_EXPR
2935 && TREE_THIS_VOLATILE (decl));
2936 used_p = (TREE_USED (decl)
2937 || (TREE_CODE (decl) != SAVE_EXPR
2938 && DECL_INITIAL (decl) != 0));
2947 put_reg_into_stack (0, reg, type, GET_MODE (reg), GET_MODE (reg),
2948 volatile_p, ADDRESSOF_REGNO (r), used_p, ht);
2951 /* List of replacements made below in purge_addressof_1 when creating
2952 bitfield insertions. */
2953 static rtx purge_bitfield_addressof_replacements;
2955 /* List of replacements made below in purge_addressof_1 for patterns
2956 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2957 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2958 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2959 enough in complex cases, e.g. when some field values can be
2960 extracted by usage MEM with narrower mode. */
2961 static rtx purge_addressof_replacements;
2963 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2964 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2965 the stack. If the function returns FALSE then the replacement could not
2969 purge_addressof_1 (loc, insn, force, store, ht)
2973 struct hash_table *ht;
2981 /* Re-start here to avoid recursion in common cases. */
2988 code = GET_CODE (x);
2990 /* If we don't return in any of the cases below, we will recurse inside
2991 the RTX, which will normally result in any ADDRESSOF being forced into
2995 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1, ht);
2996 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0, ht);
2999 else if (code == ADDRESSOF)
3003 if (GET_CODE (XEXP (x, 0)) != MEM)
3005 put_addressof_into_stack (x, ht);
3009 /* We must create a copy of the rtx because it was created by
3010 overwriting a REG rtx which is always shared. */
3011 sub = copy_rtx (XEXP (XEXP (x, 0), 0));
3012 if (validate_change (insn, loc, sub, 0)
3013 || validate_replace_rtx (x, sub, insn))
3017 sub = force_operand (sub, NULL_RTX);
3018 if (! validate_change (insn, loc, sub, 0)
3019 && ! validate_replace_rtx (x, sub, insn))
3022 insns = gen_sequence ();
3024 emit_insn_before (insns, insn);
3028 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
3030 rtx sub = XEXP (XEXP (x, 0), 0);
3032 if (GET_CODE (sub) == MEM)
3033 sub = adjust_address_nv (sub, GET_MODE (x), 0);
3034 else if (GET_CODE (sub) == REG
3035 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
3037 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
3039 int size_x, size_sub;
3043 /* When processing REG_NOTES look at the list of
3044 replacements done on the insn to find the register that X
3048 for (tem = purge_bitfield_addressof_replacements;
3050 tem = XEXP (XEXP (tem, 1), 1))
3051 if (rtx_equal_p (x, XEXP (tem, 0)))
3053 *loc = XEXP (XEXP (tem, 1), 0);
3057 /* See comment for purge_addressof_replacements. */
3058 for (tem = purge_addressof_replacements;
3060 tem = XEXP (XEXP (tem, 1), 1))
3061 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3063 rtx z = XEXP (XEXP (tem, 1), 0);
3065 if (GET_MODE (x) == GET_MODE (z)
3066 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
3067 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
3070 /* It can happen that the note may speak of things
3071 in a wider (or just different) mode than the
3072 code did. This is especially true of
3075 if (GET_CODE (z) == SUBREG && SUBREG_BYTE (z) == 0)
3078 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3079 && (GET_MODE_SIZE (GET_MODE (x))
3080 > GET_MODE_SIZE (GET_MODE (z))))
3082 /* This can occur as a result in invalid
3083 pointer casts, e.g. float f; ...
3084 *(long long int *)&f.
3085 ??? We could emit a warning here, but
3086 without a line number that wouldn't be
3088 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
3091 z = gen_lowpart (GET_MODE (x), z);
3097 /* Sometimes we may not be able to find the replacement. For
3098 example when the original insn was a MEM in a wider mode,
3099 and the note is part of a sign extension of a narrowed
3100 version of that MEM. Gcc testcase compile/990829-1.c can
3101 generate an example of this siutation. Rather than complain
3102 we return false, which will prompt our caller to remove the
3107 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3108 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3110 /* Don't even consider working with paradoxical subregs,
3111 or the moral equivalent seen here. */
3112 if (size_x <= size_sub
3113 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3115 /* Do a bitfield insertion to mirror what would happen
3122 rtx p = PREV_INSN (insn);
3125 val = gen_reg_rtx (GET_MODE (x));
3126 if (! validate_change (insn, loc, val, 0))
3128 /* Discard the current sequence and put the
3129 ADDRESSOF on stack. */
3133 seq = gen_sequence ();
3135 emit_insn_before (seq, insn);
3136 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3140 store_bit_field (sub, size_x, 0, GET_MODE (x),
3141 val, GET_MODE_SIZE (GET_MODE (sub)),
3142 GET_MODE_ALIGNMENT (GET_MODE (sub)));
3144 /* Make sure to unshare any shared rtl that store_bit_field
3145 might have created. */
3146 unshare_all_rtl_again (get_insns ());
3148 seq = gen_sequence ();
3150 p = emit_insn_after (seq, insn);
3151 if (NEXT_INSN (insn))
3152 compute_insns_for_mem (NEXT_INSN (insn),
3153 p ? NEXT_INSN (p) : NULL_RTX,
3158 rtx p = PREV_INSN (insn);
3161 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3162 GET_MODE (x), GET_MODE (x),
3163 GET_MODE_SIZE (GET_MODE (sub)),
3164 GET_MODE_SIZE (GET_MODE (sub)));
3166 if (! validate_change (insn, loc, val, 0))
3168 /* Discard the current sequence and put the
3169 ADDRESSOF on stack. */
3174 seq = gen_sequence ();
3176 emit_insn_before (seq, insn);
3177 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3181 /* Remember the replacement so that the same one can be done
3182 on the REG_NOTES. */
3183 purge_bitfield_addressof_replacements
3184 = gen_rtx_EXPR_LIST (VOIDmode, x,
3187 purge_bitfield_addressof_replacements));
3189 /* We replaced with a reg -- all done. */
3194 else if (validate_change (insn, loc, sub, 0))
3196 /* Remember the replacement so that the same one can be done
3197 on the REG_NOTES. */
3198 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3202 for (tem = purge_addressof_replacements;
3204 tem = XEXP (XEXP (tem, 1), 1))
3205 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3207 XEXP (XEXP (tem, 1), 0) = sub;
3210 purge_addressof_replacements
3211 = gen_rtx (EXPR_LIST, VOIDmode, XEXP (x, 0),
3212 gen_rtx_EXPR_LIST (VOIDmode, sub,
3213 purge_addressof_replacements));
3221 /* Scan all subexpressions. */
3222 fmt = GET_RTX_FORMAT (code);
3223 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3226 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0, ht);
3227 else if (*fmt == 'E')
3228 for (j = 0; j < XVECLEN (x, i); j++)
3229 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0, ht);
3235 /* Return a new hash table entry in HT. */
3237 static struct hash_entry *
3238 insns_for_mem_newfunc (he, ht, k)
3239 struct hash_entry *he;
3240 struct hash_table *ht;
3241 hash_table_key k ATTRIBUTE_UNUSED;
3243 struct insns_for_mem_entry *ifmhe;
3247 ifmhe = ((struct insns_for_mem_entry *)
3248 hash_allocate (ht, sizeof (struct insns_for_mem_entry)));
3249 ifmhe->insns = NULL_RTX;
3254 /* Return a hash value for K, a REG. */
3256 static unsigned long
3257 insns_for_mem_hash (k)
3260 /* K is really a RTX. Just use the address as the hash value. */
3261 return (unsigned long) k;
3264 /* Return non-zero if K1 and K2 (two REGs) are the same. */
3267 insns_for_mem_comp (k1, k2)
3274 struct insns_for_mem_walk_info {
3275 /* The hash table that we are using to record which INSNs use which
3277 struct hash_table *ht;
3279 /* The INSN we are currently proessing. */
3282 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3283 to find the insns that use the REGs in the ADDRESSOFs. */
3287 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3288 that might be used in an ADDRESSOF expression, record this INSN in
3289 the hash table given by DATA (which is really a pointer to an
3290 insns_for_mem_walk_info structure). */
3293 insns_for_mem_walk (r, data)
3297 struct insns_for_mem_walk_info *ifmwi
3298 = (struct insns_for_mem_walk_info *) data;
3300 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3301 && GET_CODE (XEXP (*r, 0)) == REG)
3302 hash_lookup (ifmwi->ht, XEXP (*r, 0), /*create=*/1, /*copy=*/0);
3303 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3305 /* Lookup this MEM in the hashtable, creating it if necessary. */
3306 struct insns_for_mem_entry *ifme
3307 = (struct insns_for_mem_entry *) hash_lookup (ifmwi->ht,
3312 /* If we have not already recorded this INSN, do so now. Since
3313 we process the INSNs in order, we know that if we have
3314 recorded it it must be at the front of the list. */
3315 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3316 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3323 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3324 which REGs in HT. */
3327 compute_insns_for_mem (insns, last_insn, ht)
3330 struct hash_table *ht;
3333 struct insns_for_mem_walk_info ifmwi;
3336 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3337 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3341 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3345 /* Helper function for purge_addressof called through for_each_rtx.
3346 Returns true iff the rtl is an ADDRESSOF. */
3349 is_addressof (rtl, data)
3351 void *data ATTRIBUTE_UNUSED;
3353 return GET_CODE (*rtl) == ADDRESSOF;
3356 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3357 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3361 purge_addressof (insns)
3365 struct hash_table ht;
3367 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3368 requires a fixup pass over the instruction stream to correct
3369 INSNs that depended on the REG being a REG, and not a MEM. But,
3370 these fixup passes are slow. Furthermore, most MEMs are not
3371 mentioned in very many instructions. So, we speed up the process
3372 by pre-calculating which REGs occur in which INSNs; that allows
3373 us to perform the fixup passes much more quickly. */
3374 hash_table_init (&ht,
3375 insns_for_mem_newfunc,
3377 insns_for_mem_comp);
3378 compute_insns_for_mem (insns, NULL_RTX, &ht);
3380 for (insn = insns; insn; insn = NEXT_INSN (insn))
3381 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3382 || GET_CODE (insn) == CALL_INSN)
3384 if (! purge_addressof_1 (&PATTERN (insn), insn,
3385 asm_noperands (PATTERN (insn)) > 0, 0, &ht))
3386 /* If we could not replace the ADDRESSOFs in the insn,
3387 something is wrong. */
3390 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, &ht))
3392 /* If we could not replace the ADDRESSOFs in the insn's notes,
3393 we can just remove the offending notes instead. */
3396 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3398 /* If we find a REG_RETVAL note then the insn is a libcall.
3399 Such insns must have REG_EQUAL notes as well, in order
3400 for later passes of the compiler to work. So it is not
3401 safe to delete the notes here, and instead we abort. */
3402 if (REG_NOTE_KIND (note) == REG_RETVAL)
3404 if (for_each_rtx (¬e, is_addressof, NULL))
3405 remove_note (insn, note);
3411 hash_table_free (&ht);
3412 purge_bitfield_addressof_replacements = 0;
3413 purge_addressof_replacements = 0;
3415 /* REGs are shared. purge_addressof will destructively replace a REG
3416 with a MEM, which creates shared MEMs.
3418 Unfortunately, the children of put_reg_into_stack assume that MEMs
3419 referring to the same stack slot are shared (fixup_var_refs and
3420 the associated hash table code).
3422 So, we have to do another unsharing pass after we have flushed any
3423 REGs that had their address taken into the stack.
3425 It may be worth tracking whether or not we converted any REGs into
3426 MEMs to avoid this overhead when it is not needed. */
3427 unshare_all_rtl_again (get_insns ());
3430 /* Convert a SET of a hard subreg to a set of the appropriet hard
3431 register. A subroutine of purge_hard_subreg_sets. */
3434 purge_single_hard_subreg_set (pattern)
3437 rtx reg = SET_DEST (pattern);
3438 enum machine_mode mode = GET_MODE (SET_DEST (pattern));
3441 if (GET_CODE (reg) == SUBREG && GET_CODE (SUBREG_REG (reg)) == REG
3442 && REGNO (SUBREG_REG (reg)) < FIRST_PSEUDO_REGISTER)
3444 offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)),
3445 GET_MODE (SUBREG_REG (reg)),
3448 reg = SUBREG_REG (reg);
3452 if (GET_CODE (reg) == REG && REGNO (reg) < FIRST_PSEUDO_REGISTER)
3454 reg = gen_rtx_REG (mode, REGNO (reg) + offset);
3455 SET_DEST (pattern) = reg;
3459 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The
3460 only such SETs that we expect to see are those left in because
3461 integrate can't handle sets of parts of a return value register.
3463 We don't use alter_subreg because we only want to eliminate subregs
3464 of hard registers. */
3467 purge_hard_subreg_sets (insn)
3470 for (; insn; insn = NEXT_INSN (insn))
3474 rtx pattern = PATTERN (insn);
3475 switch (GET_CODE (pattern))
3478 if (GET_CODE (SET_DEST (pattern)) == SUBREG)
3479 purge_single_hard_subreg_set (pattern);
3484 for (j = XVECLEN (pattern, 0) - 1; j >= 0; j--)
3486 rtx inner_pattern = XVECEXP (pattern, 0, j);
3487 if (GET_CODE (inner_pattern) == SET
3488 && GET_CODE (SET_DEST (inner_pattern)) == SUBREG)
3489 purge_single_hard_subreg_set (inner_pattern);
3500 /* Pass through the INSNS of function FNDECL and convert virtual register
3501 references to hard register references. */
3504 instantiate_virtual_regs (fndecl, insns)
3511 /* Compute the offsets to use for this function. */
3512 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3513 var_offset = STARTING_FRAME_OFFSET;
3514 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3515 out_arg_offset = STACK_POINTER_OFFSET;
3516 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl);
3518 /* Scan all variables and parameters of this function. For each that is
3519 in memory, instantiate all virtual registers if the result is a valid
3520 address. If not, we do it later. That will handle most uses of virtual
3521 regs on many machines. */
3522 instantiate_decls (fndecl, 1);
3524 /* Initialize recognition, indicating that volatile is OK. */
3527 /* Scan through all the insns, instantiating every virtual register still
3529 for (insn = insns; insn; insn = NEXT_INSN (insn))
3530 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3531 || GET_CODE (insn) == CALL_INSN)
3533 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3534 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3535 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
3536 if (GET_CODE (insn) == CALL_INSN)
3537 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn),
3541 /* Instantiate the stack slots for the parm registers, for later use in
3542 addressof elimination. */
3543 for (i = 0; i < max_parm_reg; ++i)
3544 if (parm_reg_stack_loc[i])
3545 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3547 /* Now instantiate the remaining register equivalences for debugging info.
3548 These will not be valid addresses. */
3549 instantiate_decls (fndecl, 0);
3551 /* Indicate that, from now on, assign_stack_local should use
3552 frame_pointer_rtx. */
3553 virtuals_instantiated = 1;
3556 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3557 all virtual registers in their DECL_RTL's.
3559 If VALID_ONLY, do this only if the resulting address is still valid.
3560 Otherwise, always do it. */
3563 instantiate_decls (fndecl, valid_only)
3569 /* Process all parameters of the function. */
3570 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3572 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3573 HOST_WIDE_INT size_rtl;
3575 instantiate_decl (DECL_RTL (decl), size, valid_only);
3577 /* If the parameter was promoted, then the incoming RTL mode may be
3578 larger than the declared type size. We must use the larger of
3580 size_rtl = GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl)));
3581 size = MAX (size_rtl, size);
3582 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3585 /* Now process all variables defined in the function or its subblocks. */
3586 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3589 /* Subroutine of instantiate_decls: Process all decls in the given
3590 BLOCK node and all its subblocks. */
3593 instantiate_decls_1 (let, valid_only)
3599 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3600 if (DECL_RTL_SET_P (t))
3601 instantiate_decl (DECL_RTL (t),
3602 int_size_in_bytes (TREE_TYPE (t)),
3605 /* Process all subblocks. */
3606 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3607 instantiate_decls_1 (t, valid_only);
3610 /* Subroutine of the preceding procedures: Given RTL representing a
3611 decl and the size of the object, do any instantiation required.
3613 If VALID_ONLY is non-zero, it means that the RTL should only be
3614 changed if the new address is valid. */
3617 instantiate_decl (x, size, valid_only)
3622 enum machine_mode mode;
3625 /* If this is not a MEM, no need to do anything. Similarly if the
3626 address is a constant or a register that is not a virtual register. */
3628 if (x == 0 || GET_CODE (x) != MEM)
3632 if (CONSTANT_P (addr)
3633 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3634 || (GET_CODE (addr) == REG
3635 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3636 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3639 /* If we should only do this if the address is valid, copy the address.
3640 We need to do this so we can undo any changes that might make the
3641 address invalid. This copy is unfortunate, but probably can't be
3645 addr = copy_rtx (addr);
3647 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3649 if (valid_only && size >= 0)
3651 unsigned HOST_WIDE_INT decl_size = size;
3653 /* Now verify that the resulting address is valid for every integer or
3654 floating-point mode up to and including SIZE bytes long. We do this
3655 since the object might be accessed in any mode and frame addresses
3658 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3659 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3660 mode = GET_MODE_WIDER_MODE (mode))
3661 if (! memory_address_p (mode, addr))
3664 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3665 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3666 mode = GET_MODE_WIDER_MODE (mode))
3667 if (! memory_address_p (mode, addr))
3671 /* Put back the address now that we have updated it and we either know
3672 it is valid or we don't care whether it is valid. */
3677 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
3678 is a virtual register, return the requivalent hard register and set the
3679 offset indirectly through the pointer. Otherwise, return 0. */
3682 instantiate_new_reg (x, poffset)
3684 HOST_WIDE_INT *poffset;
3687 HOST_WIDE_INT offset;
3689 if (x == virtual_incoming_args_rtx)
3690 new = arg_pointer_rtx, offset = in_arg_offset;
3691 else if (x == virtual_stack_vars_rtx)
3692 new = frame_pointer_rtx, offset = var_offset;
3693 else if (x == virtual_stack_dynamic_rtx)
3694 new = stack_pointer_rtx, offset = dynamic_offset;
3695 else if (x == virtual_outgoing_args_rtx)
3696 new = stack_pointer_rtx, offset = out_arg_offset;
3697 else if (x == virtual_cfa_rtx)
3698 new = arg_pointer_rtx, offset = cfa_offset;
3706 /* Given a pointer to a piece of rtx and an optional pointer to the
3707 containing object, instantiate any virtual registers present in it.
3709 If EXTRA_INSNS, we always do the replacement and generate
3710 any extra insns before OBJECT. If it zero, we do nothing if replacement
3713 Return 1 if we either had nothing to do or if we were able to do the
3714 needed replacement. Return 0 otherwise; we only return zero if
3715 EXTRA_INSNS is zero.
3717 We first try some simple transformations to avoid the creation of extra
3721 instantiate_virtual_regs_1 (loc, object, extra_insns)
3729 HOST_WIDE_INT offset = 0;
3735 /* Re-start here to avoid recursion in common cases. */
3742 code = GET_CODE (x);
3744 /* Check for some special cases. */
3761 /* We are allowed to set the virtual registers. This means that
3762 the actual register should receive the source minus the
3763 appropriate offset. This is used, for example, in the handling
3764 of non-local gotos. */
3765 if ((new = instantiate_new_reg (SET_DEST (x), &offset)) != 0)
3767 rtx src = SET_SRC (x);
3769 /* We are setting the register, not using it, so the relevant
3770 offset is the negative of the offset to use were we using
3773 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3775 /* The only valid sources here are PLUS or REG. Just do
3776 the simplest possible thing to handle them. */
3777 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3781 if (GET_CODE (src) != REG)
3782 temp = force_operand (src, NULL_RTX);
3785 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3789 emit_insns_before (seq, object);
3792 if (! validate_change (object, &SET_SRC (x), temp, 0)
3799 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3804 /* Handle special case of virtual register plus constant. */
3805 if (CONSTANT_P (XEXP (x, 1)))
3807 rtx old, new_offset;
3809 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3810 if (GET_CODE (XEXP (x, 0)) == PLUS)
3812 if ((new = instantiate_new_reg (XEXP (XEXP (x, 0), 0), &offset)))
3814 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3816 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3825 #ifdef POINTERS_EXTEND_UNSIGNED
3826 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
3827 we can commute the PLUS and SUBREG because pointers into the
3828 frame are well-behaved. */
3829 else if (GET_CODE (XEXP (x, 0)) == SUBREG && GET_MODE (x) == ptr_mode
3830 && GET_CODE (XEXP (x, 1)) == CONST_INT
3832 = instantiate_new_reg (SUBREG_REG (XEXP (x, 0)),
3834 && validate_change (object, loc,
3835 plus_constant (gen_lowpart (ptr_mode,
3838 + INTVAL (XEXP (x, 1))),
3842 else if ((new = instantiate_new_reg (XEXP (x, 0), &offset)) == 0)
3844 /* We know the second operand is a constant. Unless the
3845 first operand is a REG (which has been already checked),
3846 it needs to be checked. */
3847 if (GET_CODE (XEXP (x, 0)) != REG)
3855 new_offset = plus_constant (XEXP (x, 1), offset);
3857 /* If the new constant is zero, try to replace the sum with just
3859 if (new_offset == const0_rtx
3860 && validate_change (object, loc, new, 0))
3863 /* Next try to replace the register and new offset.
3864 There are two changes to validate here and we can't assume that
3865 in the case of old offset equals new just changing the register
3866 will yield a valid insn. In the interests of a little efficiency,
3867 however, we only call validate change once (we don't queue up the
3868 changes and then call apply_change_group). */
3872 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3873 : (XEXP (x, 0) = new,
3874 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3882 /* Otherwise copy the new constant into a register and replace
3883 constant with that register. */
3884 temp = gen_reg_rtx (Pmode);
3886 if (validate_change (object, &XEXP (x, 1), temp, 0))
3887 emit_insn_before (gen_move_insn (temp, new_offset), object);
3890 /* If that didn't work, replace this expression with a
3891 register containing the sum. */
3894 new = gen_rtx_PLUS (Pmode, new, new_offset);
3897 temp = force_operand (new, NULL_RTX);
3901 emit_insns_before (seq, object);
3902 if (! validate_change (object, loc, temp, 0)
3903 && ! validate_replace_rtx (x, temp, object))
3911 /* Fall through to generic two-operand expression case. */
3917 case DIV: case UDIV:
3918 case MOD: case UMOD:
3919 case AND: case IOR: case XOR:
3920 case ROTATERT: case ROTATE:
3921 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3923 case GE: case GT: case GEU: case GTU:
3924 case LE: case LT: case LEU: case LTU:
3925 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3926 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3931 /* Most cases of MEM that convert to valid addresses have already been
3932 handled by our scan of decls. The only special handling we
3933 need here is to make a copy of the rtx to ensure it isn't being
3934 shared if we have to change it to a pseudo.
3936 If the rtx is a simple reference to an address via a virtual register,
3937 it can potentially be shared. In such cases, first try to make it
3938 a valid address, which can also be shared. Otherwise, copy it and
3941 First check for common cases that need no processing. These are
3942 usually due to instantiation already being done on a previous instance
3946 if (CONSTANT_ADDRESS_P (temp)
3947 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3948 || temp == arg_pointer_rtx
3950 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3951 || temp == hard_frame_pointer_rtx
3953 || temp == frame_pointer_rtx)
3956 if (GET_CODE (temp) == PLUS
3957 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3958 && (XEXP (temp, 0) == frame_pointer_rtx
3959 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3960 || XEXP (temp, 0) == hard_frame_pointer_rtx
3962 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3963 || XEXP (temp, 0) == arg_pointer_rtx
3968 if (temp == virtual_stack_vars_rtx
3969 || temp == virtual_incoming_args_rtx
3970 || (GET_CODE (temp) == PLUS
3971 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3972 && (XEXP (temp, 0) == virtual_stack_vars_rtx
3973 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
3975 /* This MEM may be shared. If the substitution can be done without
3976 the need to generate new pseudos, we want to do it in place
3977 so all copies of the shared rtx benefit. The call below will
3978 only make substitutions if the resulting address is still
3981 Note that we cannot pass X as the object in the recursive call
3982 since the insn being processed may not allow all valid
3983 addresses. However, if we were not passed on object, we can
3984 only modify X without copying it if X will have a valid
3987 ??? Also note that this can still lose if OBJECT is an insn that
3988 has less restrictions on an address that some other insn.
3989 In that case, we will modify the shared address. This case
3990 doesn't seem very likely, though. One case where this could
3991 happen is in the case of a USE or CLOBBER reference, but we
3992 take care of that below. */
3994 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
3995 object ? object : x, 0))
3998 /* Otherwise make a copy and process that copy. We copy the entire
3999 RTL expression since it might be a PLUS which could also be
4001 *loc = x = copy_rtx (x);
4004 /* Fall through to generic unary operation case. */
4006 case STRICT_LOW_PART:
4008 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
4009 case SIGN_EXTEND: case ZERO_EXTEND:
4010 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
4011 case FLOAT: case FIX:
4012 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
4016 /* These case either have just one operand or we know that we need not
4017 check the rest of the operands. */
4023 /* If the operand is a MEM, see if the change is a valid MEM. If not,
4024 go ahead and make the invalid one, but do it to a copy. For a REG,
4025 just make the recursive call, since there's no chance of a problem. */
4027 if ((GET_CODE (XEXP (x, 0)) == MEM
4028 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
4030 || (GET_CODE (XEXP (x, 0)) == REG
4031 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
4034 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
4039 /* Try to replace with a PLUS. If that doesn't work, compute the sum
4040 in front of this insn and substitute the temporary. */
4041 if ((new = instantiate_new_reg (x, &offset)) != 0)
4043 temp = plus_constant (new, offset);
4044 if (!validate_change (object, loc, temp, 0))
4050 temp = force_operand (temp, NULL_RTX);
4054 emit_insns_before (seq, object);
4055 if (! validate_change (object, loc, temp, 0)
4056 && ! validate_replace_rtx (x, temp, object))
4064 if (GET_CODE (XEXP (x, 0)) == REG)
4067 else if (GET_CODE (XEXP (x, 0)) == MEM)
4069 /* If we have a (addressof (mem ..)), do any instantiation inside
4070 since we know we'll be making the inside valid when we finally
4071 remove the ADDRESSOF. */
4072 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
4081 /* Scan all subexpressions. */
4082 fmt = GET_RTX_FORMAT (code);
4083 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
4086 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
4089 else if (*fmt == 'E')
4090 for (j = 0; j < XVECLEN (x, i); j++)
4091 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
4098 /* Optimization: assuming this function does not receive nonlocal gotos,
4099 delete the handlers for such, as well as the insns to establish
4100 and disestablish them. */
4106 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4108 /* Delete the handler by turning off the flag that would
4109 prevent jump_optimize from deleting it.
4110 Also permit deletion of the nonlocal labels themselves
4111 if nothing local refers to them. */
4112 if (GET_CODE (insn) == CODE_LABEL)
4116 LABEL_PRESERVE_P (insn) = 0;
4118 /* Remove it from the nonlocal_label list, to avoid confusing
4120 for (t = nonlocal_labels, last_t = 0; t;
4121 last_t = t, t = TREE_CHAIN (t))
4122 if (DECL_RTL (TREE_VALUE (t)) == insn)
4127 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
4129 TREE_CHAIN (last_t) = TREE_CHAIN (t);
4132 if (GET_CODE (insn) == INSN)
4136 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
4137 if (reg_mentioned_p (t, PATTERN (insn)))
4143 || (nonlocal_goto_stack_level != 0
4144 && reg_mentioned_p (nonlocal_goto_stack_level,
4154 return max_parm_reg;
4157 /* Return the first insn following those generated by `assign_parms'. */
4160 get_first_nonparm_insn ()
4163 return NEXT_INSN (last_parm_insn);
4164 return get_insns ();
4167 /* Return the first NOTE_INSN_BLOCK_BEG note in the function.
4168 Crash if there is none. */
4171 get_first_block_beg ()
4173 register rtx searcher;
4174 register rtx insn = get_first_nonparm_insn ();
4176 for (searcher = insn; searcher; searcher = NEXT_INSN (searcher))
4177 if (GET_CODE (searcher) == NOTE
4178 && NOTE_LINE_NUMBER (searcher) == NOTE_INSN_BLOCK_BEG)
4181 abort (); /* Invalid call to this function. (See comments above.) */
4185 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4186 This means a type for which function calls must pass an address to the
4187 function or get an address back from the function.
4188 EXP may be a type node or an expression (whose type is tested). */
4191 aggregate_value_p (exp)
4194 int i, regno, nregs;
4197 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4199 if (TREE_CODE (type) == VOID_TYPE)
4201 if (RETURN_IN_MEMORY (type))
4203 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4204 and thus can't be returned in registers. */
4205 if (TREE_ADDRESSABLE (type))
4207 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4209 /* Make sure we have suitable call-clobbered regs to return
4210 the value in; if not, we must return it in memory. */
4211 reg = hard_function_value (type, 0, 0);
4213 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4215 if (GET_CODE (reg) != REG)
4218 regno = REGNO (reg);
4219 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
4220 for (i = 0; i < nregs; i++)
4221 if (! call_used_regs[regno + i])
4226 /* Assign RTL expressions to the function's parameters.
4227 This may involve copying them into registers and using
4228 those registers as the RTL for them. */
4231 assign_parms (fndecl)
4235 register rtx entry_parm = 0;
4236 register rtx stack_parm = 0;
4237 CUMULATIVE_ARGS args_so_far;
4238 enum machine_mode promoted_mode, passed_mode;
4239 enum machine_mode nominal_mode, promoted_nominal_mode;
4241 /* Total space needed so far for args on the stack,
4242 given as a constant and a tree-expression. */
4243 struct args_size stack_args_size;
4244 tree fntype = TREE_TYPE (fndecl);
4245 tree fnargs = DECL_ARGUMENTS (fndecl);
4246 /* This is used for the arg pointer when referring to stack args. */
4247 rtx internal_arg_pointer;
4248 /* This is a dummy PARM_DECL that we used for the function result if
4249 the function returns a structure. */
4250 tree function_result_decl = 0;
4251 #ifdef SETUP_INCOMING_VARARGS
4252 int varargs_setup = 0;
4254 rtx conversion_insns = 0;
4255 struct args_size alignment_pad;
4257 /* Nonzero if the last arg is named `__builtin_va_alist',
4258 which is used on some machines for old-fashioned non-ANSI varargs.h;
4259 this should be stuck onto the stack as if it had arrived there. */
4261 = (current_function_varargs
4263 && (parm = tree_last (fnargs)) != 0
4265 && (! strcmp (IDENTIFIER_POINTER (DECL_NAME (parm)),
4266 "__builtin_va_alist")));
4268 /* Nonzero if function takes extra anonymous args.
4269 This means the last named arg must be on the stack
4270 right before the anonymous ones. */
4272 = (TYPE_ARG_TYPES (fntype) != 0
4273 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4274 != void_type_node));
4276 current_function_stdarg = stdarg;
4278 /* If the reg that the virtual arg pointer will be translated into is
4279 not a fixed reg or is the stack pointer, make a copy of the virtual
4280 arg pointer, and address parms via the copy. The frame pointer is
4281 considered fixed even though it is not marked as such.
4283 The second time through, simply use ap to avoid generating rtx. */
4285 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4286 || ! (fixed_regs[ARG_POINTER_REGNUM]
4287 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4288 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4290 internal_arg_pointer = virtual_incoming_args_rtx;
4291 current_function_internal_arg_pointer = internal_arg_pointer;
4293 stack_args_size.constant = 0;
4294 stack_args_size.var = 0;
4296 /* If struct value address is treated as the first argument, make it so. */
4297 if (aggregate_value_p (DECL_RESULT (fndecl))
4298 && ! current_function_returns_pcc_struct
4299 && struct_value_incoming_rtx == 0)
4301 tree type = build_pointer_type (TREE_TYPE (fntype));
4303 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4305 DECL_ARG_TYPE (function_result_decl) = type;
4306 TREE_CHAIN (function_result_decl) = fnargs;
4307 fnargs = function_result_decl;
4310 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4311 parm_reg_stack_loc = (rtx *) xcalloc (max_parm_reg, sizeof (rtx));
4313 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4314 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4316 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, 0);
4319 /* We haven't yet found an argument that we must push and pretend the
4321 current_function_pretend_args_size = 0;
4323 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4325 struct args_size stack_offset;
4326 struct args_size arg_size;
4327 int passed_pointer = 0;
4328 int did_conversion = 0;
4329 tree passed_type = DECL_ARG_TYPE (parm);
4330 tree nominal_type = TREE_TYPE (parm);
4333 /* Set LAST_NAMED if this is last named arg before some
4335 int last_named = ((TREE_CHAIN (parm) == 0
4336 || DECL_NAME (TREE_CHAIN (parm)) == 0)
4337 && (stdarg || current_function_varargs));
4338 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4339 most machines, if this is a varargs/stdarg function, then we treat
4340 the last named arg as if it were anonymous too. */
4341 int named_arg = STRICT_ARGUMENT_NAMING ? 1 : ! last_named;
4343 if (TREE_TYPE (parm) == error_mark_node
4344 /* This can happen after weird syntax errors
4345 or if an enum type is defined among the parms. */
4346 || TREE_CODE (parm) != PARM_DECL
4347 || passed_type == NULL)
4349 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx));
4350 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4351 TREE_USED (parm) = 1;
4355 /* For varargs.h function, save info about regs and stack space
4356 used by the individual args, not including the va_alist arg. */
4357 if (hide_last_arg && last_named)
4358 current_function_args_info = args_so_far;
4360 /* Find mode of arg as it is passed, and mode of arg
4361 as it should be during execution of this function. */
4362 passed_mode = TYPE_MODE (passed_type);
4363 nominal_mode = TYPE_MODE (nominal_type);
4365 /* If the parm's mode is VOID, its value doesn't matter,
4366 and avoid the usual things like emit_move_insn that could crash. */
4367 if (nominal_mode == VOIDmode)
4369 SET_DECL_RTL (parm, const0_rtx);
4370 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4374 /* If the parm is to be passed as a transparent union, use the
4375 type of the first field for the tests below. We have already
4376 verified that the modes are the same. */
4377 if (DECL_TRANSPARENT_UNION (parm)
4378 || (TREE_CODE (passed_type) == UNION_TYPE
4379 && TYPE_TRANSPARENT_UNION (passed_type)))
4380 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4382 /* See if this arg was passed by invisible reference. It is if
4383 it is an object whose size depends on the contents of the
4384 object itself or if the machine requires these objects be passed
4387 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
4388 && contains_placeholder_p (TYPE_SIZE (passed_type)))
4389 || TREE_ADDRESSABLE (passed_type)
4390 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4391 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4392 passed_type, named_arg)
4396 passed_type = nominal_type = build_pointer_type (passed_type);
4398 passed_mode = nominal_mode = Pmode;
4401 promoted_mode = passed_mode;
4403 #ifdef PROMOTE_FUNCTION_ARGS
4404 /* Compute the mode in which the arg is actually extended to. */
4405 unsignedp = TREE_UNSIGNED (passed_type);
4406 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4409 /* Let machine desc say which reg (if any) the parm arrives in.
4410 0 means it arrives on the stack. */
4411 #ifdef FUNCTION_INCOMING_ARG
4412 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4413 passed_type, named_arg);
4415 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4416 passed_type, named_arg);
4419 if (entry_parm == 0)
4420 promoted_mode = passed_mode;
4422 #ifdef SETUP_INCOMING_VARARGS
4423 /* If this is the last named parameter, do any required setup for
4424 varargs or stdargs. We need to know about the case of this being an
4425 addressable type, in which case we skip the registers it
4426 would have arrived in.
4428 For stdargs, LAST_NAMED will be set for two parameters, the one that
4429 is actually the last named, and the dummy parameter. We only
4430 want to do this action once.
4432 Also, indicate when RTL generation is to be suppressed. */
4433 if (last_named && !varargs_setup)
4435 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
4436 current_function_pretend_args_size, 0);
4441 /* Determine parm's home in the stack,
4442 in case it arrives in the stack or we should pretend it did.
4444 Compute the stack position and rtx where the argument arrives
4447 There is one complexity here: If this was a parameter that would
4448 have been passed in registers, but wasn't only because it is
4449 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4450 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4451 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4452 0 as it was the previous time. */
4454 pretend_named = named_arg || PRETEND_OUTGOING_VARARGS_NAMED;
4455 locate_and_pad_parm (promoted_mode, passed_type,
4456 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4459 #ifdef FUNCTION_INCOMING_ARG
4460 FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4462 pretend_named) != 0,
4464 FUNCTION_ARG (args_so_far, promoted_mode,
4466 pretend_named) != 0,
4469 fndecl, &stack_args_size, &stack_offset, &arg_size,
4473 rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
4475 if (offset_rtx == const0_rtx)
4476 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4478 stack_parm = gen_rtx_MEM (promoted_mode,
4479 gen_rtx_PLUS (Pmode,
4480 internal_arg_pointer,
4483 set_mem_attributes (stack_parm, parm, 1);
4486 /* If this parameter was passed both in registers and in the stack,
4487 use the copy on the stack. */
4488 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4491 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4492 /* If this parm was passed part in regs and part in memory,
4493 pretend it arrived entirely in memory
4494 by pushing the register-part onto the stack.
4496 In the special case of a DImode or DFmode that is split,
4497 we could put it together in a pseudoreg directly,
4498 but for now that's not worth bothering with. */
4502 int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4503 passed_type, named_arg);
4507 current_function_pretend_args_size
4508 = (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
4509 / (PARM_BOUNDARY / BITS_PER_UNIT)
4510 * (PARM_BOUNDARY / BITS_PER_UNIT));
4512 /* Handle calls that pass values in multiple non-contiguous
4513 locations. The Irix 6 ABI has examples of this. */
4514 if (GET_CODE (entry_parm) == PARALLEL)
4515 emit_group_store (validize_mem (stack_parm), entry_parm,
4516 int_size_in_bytes (TREE_TYPE (parm)),
4517 TYPE_ALIGN (TREE_TYPE (parm)));
4520 move_block_from_reg (REGNO (entry_parm),
4521 validize_mem (stack_parm), nregs,
4522 int_size_in_bytes (TREE_TYPE (parm)));
4524 entry_parm = stack_parm;
4529 /* If we didn't decide this parm came in a register,
4530 by default it came on the stack. */
4531 if (entry_parm == 0)
4532 entry_parm = stack_parm;
4534 /* Record permanently how this parm was passed. */
4535 DECL_INCOMING_RTL (parm) = entry_parm;
4537 /* If there is actually space on the stack for this parm,
4538 count it in stack_args_size; otherwise set stack_parm to 0
4539 to indicate there is no preallocated stack slot for the parm. */
4541 if (entry_parm == stack_parm
4542 || (GET_CODE (entry_parm) == PARALLEL
4543 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4544 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4545 /* On some machines, even if a parm value arrives in a register
4546 there is still an (uninitialized) stack slot allocated for it.
4548 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4549 whether this parameter already has a stack slot allocated,
4550 because an arg block exists only if current_function_args_size
4551 is larger than some threshold, and we haven't calculated that
4552 yet. So, for now, we just assume that stack slots never exist
4554 || REG_PARM_STACK_SPACE (fndecl) > 0
4558 stack_args_size.constant += arg_size.constant;
4560 ADD_PARM_SIZE (stack_args_size, arg_size.var);
4563 /* No stack slot was pushed for this parm. */
4566 /* Update info on where next arg arrives in registers. */
4568 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4569 passed_type, named_arg);
4571 /* If we can't trust the parm stack slot to be aligned enough
4572 for its ultimate type, don't use that slot after entry.
4573 We'll make another stack slot, if we need one. */
4575 unsigned int thisparm_boundary
4576 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4578 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4582 /* If parm was passed in memory, and we need to convert it on entry,
4583 don't store it back in that same slot. */
4585 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4588 /* When an argument is passed in multiple locations, we can't
4589 make use of this information, but we can save some copying if
4590 the whole argument is passed in a single register. */
4591 if (GET_CODE (entry_parm) == PARALLEL
4592 && nominal_mode != BLKmode && passed_mode != BLKmode)
4594 int i, len = XVECLEN (entry_parm, 0);
4596 for (i = 0; i < len; i++)
4597 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
4598 && GET_CODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) == REG
4599 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
4601 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
4603 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
4604 DECL_INCOMING_RTL (parm) = entry_parm;
4609 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4610 in the mode in which it arrives.
4611 STACK_PARM is an RTX for a stack slot where the parameter can live
4612 during the function (in case we want to put it there).
4613 STACK_PARM is 0 if no stack slot was pushed for it.
4615 Now output code if necessary to convert ENTRY_PARM to
4616 the type in which this function declares it,
4617 and store that result in an appropriate place,
4618 which may be a pseudo reg, may be STACK_PARM,
4619 or may be a local stack slot if STACK_PARM is 0.
4621 Set DECL_RTL to that place. */
4623 if (nominal_mode == BLKmode || GET_CODE (entry_parm) == PARALLEL)
4625 /* If a BLKmode arrives in registers, copy it to a stack slot.
4626 Handle calls that pass values in multiple non-contiguous
4627 locations. The Irix 6 ABI has examples of this. */
4628 if (GET_CODE (entry_parm) == REG
4629 || GET_CODE (entry_parm) == PARALLEL)
4632 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
4635 /* Note that we will be storing an integral number of words.
4636 So we have to be careful to ensure that we allocate an
4637 integral number of words. We do this below in the
4638 assign_stack_local if space was not allocated in the argument
4639 list. If it was, this will not work if PARM_BOUNDARY is not
4640 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4641 if it becomes a problem. */
4643 if (stack_parm == 0)
4646 = assign_stack_local (GET_MODE (entry_parm),
4648 set_mem_attributes (stack_parm, parm, 1);
4651 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4654 /* Handle calls that pass values in multiple non-contiguous
4655 locations. The Irix 6 ABI has examples of this. */
4656 if (GET_CODE (entry_parm) == PARALLEL)
4657 emit_group_store (validize_mem (stack_parm), entry_parm,
4658 int_size_in_bytes (TREE_TYPE (parm)),
4659 TYPE_ALIGN (TREE_TYPE (parm)));
4661 move_block_from_reg (REGNO (entry_parm),
4662 validize_mem (stack_parm),
4663 size_stored / UNITS_PER_WORD,
4664 int_size_in_bytes (TREE_TYPE (parm)));
4666 SET_DECL_RTL (parm, stack_parm);
4668 else if (! ((! optimize
4669 && ! DECL_REGISTER (parm)
4670 && ! DECL_INLINE (fndecl))
4671 || TREE_SIDE_EFFECTS (parm)
4672 /* If -ffloat-store specified, don't put explicit
4673 float variables into registers. */
4674 || (flag_float_store
4675 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4676 /* Always assign pseudo to structure return or item passed
4677 by invisible reference. */
4678 || passed_pointer || parm == function_result_decl)
4680 /* Store the parm in a pseudoregister during the function, but we
4681 may need to do it in a wider mode. */
4683 register rtx parmreg;
4684 unsigned int regno, regnoi = 0, regnor = 0;
4686 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4688 promoted_nominal_mode
4689 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4691 parmreg = gen_reg_rtx (promoted_nominal_mode);
4692 mark_user_reg (parmreg);
4694 /* If this was an item that we received a pointer to, set DECL_RTL
4698 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)),
4700 set_mem_attributes (x, parm, 1);
4701 SET_DECL_RTL (parm, x);
4705 SET_DECL_RTL (parm, parmreg);
4706 maybe_set_unchanging (DECL_RTL (parm), parm);
4709 /* Copy the value into the register. */
4710 if (nominal_mode != passed_mode
4711 || promoted_nominal_mode != promoted_mode)
4714 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4715 mode, by the caller. We now have to convert it to
4716 NOMINAL_MODE, if different. However, PARMREG may be in
4717 a different mode than NOMINAL_MODE if it is being stored
4720 If ENTRY_PARM is a hard register, it might be in a register
4721 not valid for operating in its mode (e.g., an odd-numbered
4722 register for a DFmode). In that case, moves are the only
4723 thing valid, so we can't do a convert from there. This
4724 occurs when the calling sequence allow such misaligned
4727 In addition, the conversion may involve a call, which could
4728 clobber parameters which haven't been copied to pseudo
4729 registers yet. Therefore, we must first copy the parm to
4730 a pseudo reg here, and save the conversion until after all
4731 parameters have been moved. */
4733 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4735 emit_move_insn (tempreg, validize_mem (entry_parm));
4737 push_to_sequence (conversion_insns);
4738 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4740 if (GET_CODE (tempreg) == SUBREG
4741 && GET_MODE (tempreg) == nominal_mode
4742 && GET_CODE (SUBREG_REG (tempreg)) == REG
4743 && nominal_mode == passed_mode
4744 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm)
4745 && GET_MODE_SIZE (GET_MODE (tempreg))
4746 < GET_MODE_SIZE (GET_MODE (entry_parm)))
4748 /* The argument is already sign/zero extended, so note it
4750 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
4751 SUBREG_PROMOTED_UNSIGNED_P (tempreg) = unsignedp;
4754 /* TREE_USED gets set erroneously during expand_assignment. */
4755 save_tree_used = TREE_USED (parm);
4756 expand_assignment (parm,
4757 make_tree (nominal_type, tempreg), 0, 0);
4758 TREE_USED (parm) = save_tree_used;
4759 conversion_insns = get_insns ();
4764 emit_move_insn (parmreg, validize_mem (entry_parm));
4766 /* If we were passed a pointer but the actual value
4767 can safely live in a register, put it in one. */
4768 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4770 && ! DECL_REGISTER (parm)
4771 && ! DECL_INLINE (fndecl))
4772 || TREE_SIDE_EFFECTS (parm)
4773 /* If -ffloat-store specified, don't put explicit
4774 float variables into registers. */
4775 || (flag_float_store
4776 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE)))
4778 /* We can't use nominal_mode, because it will have been set to
4779 Pmode above. We must use the actual mode of the parm. */
4780 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4781 mark_user_reg (parmreg);
4782 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
4784 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
4785 int unsigned_p = TREE_UNSIGNED (TREE_TYPE (parm));
4786 push_to_sequence (conversion_insns);
4787 emit_move_insn (tempreg, DECL_RTL (parm));
4789 convert_to_mode (GET_MODE (parmreg),
4792 emit_move_insn (parmreg, DECL_RTL (parm));
4793 conversion_insns = get_insns();
4798 emit_move_insn (parmreg, DECL_RTL (parm));
4799 SET_DECL_RTL (parm, parmreg);
4800 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4804 #ifdef FUNCTION_ARG_CALLEE_COPIES
4805 /* If we are passed an arg by reference and it is our responsibility
4806 to make a copy, do it now.
4807 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4808 original argument, so we must recreate them in the call to
4809 FUNCTION_ARG_CALLEE_COPIES. */
4810 /* ??? Later add code to handle the case that if the argument isn't
4811 modified, don't do the copy. */
4813 else if (passed_pointer
4814 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4815 TYPE_MODE (DECL_ARG_TYPE (parm)),
4816 DECL_ARG_TYPE (parm),
4818 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4821 tree type = DECL_ARG_TYPE (parm);
4823 /* This sequence may involve a library call perhaps clobbering
4824 registers that haven't been copied to pseudos yet. */
4826 push_to_sequence (conversion_insns);
4828 if (!COMPLETE_TYPE_P (type)
4829 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4830 /* This is a variable sized object. */
4831 copy = gen_rtx_MEM (BLKmode,
4832 allocate_dynamic_stack_space
4833 (expr_size (parm), NULL_RTX,
4834 TYPE_ALIGN (type)));
4836 copy = assign_stack_temp (TYPE_MODE (type),
4837 int_size_in_bytes (type), 1);
4838 set_mem_attributes (copy, parm, 1);
4840 store_expr (parm, copy, 0);
4841 emit_move_insn (parmreg, XEXP (copy, 0));
4842 if (current_function_check_memory_usage)
4843 emit_library_call (chkr_set_right_libfunc,
4844 LCT_CONST_MAKE_BLOCK, VOIDmode, 3,
4845 XEXP (copy, 0), Pmode,
4846 GEN_INT (int_size_in_bytes (type)),
4847 TYPE_MODE (sizetype),
4848 GEN_INT (MEMORY_USE_RW),
4849 TYPE_MODE (integer_type_node));
4850 conversion_insns = get_insns ();
4854 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4856 /* In any case, record the parm's desired stack location
4857 in case we later discover it must live in the stack.
4859 If it is a COMPLEX value, store the stack location for both
4862 if (GET_CODE (parmreg) == CONCAT)
4863 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4865 regno = REGNO (parmreg);
4867 if (regno >= max_parm_reg)
4870 int old_max_parm_reg = max_parm_reg;
4872 /* It's slow to expand this one register at a time,
4873 but it's also rare and we need max_parm_reg to be
4874 precisely correct. */
4875 max_parm_reg = regno + 1;
4876 new = (rtx *) xrealloc (parm_reg_stack_loc,
4877 max_parm_reg * sizeof (rtx));
4878 memset ((char *) (new + old_max_parm_reg), 0,
4879 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4880 parm_reg_stack_loc = new;
4883 if (GET_CODE (parmreg) == CONCAT)
4885 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
4887 regnor = REGNO (gen_realpart (submode, parmreg));
4888 regnoi = REGNO (gen_imagpart (submode, parmreg));
4890 if (stack_parm != 0)
4892 parm_reg_stack_loc[regnor]
4893 = gen_realpart (submode, stack_parm);
4894 parm_reg_stack_loc[regnoi]
4895 = gen_imagpart (submode, stack_parm);
4899 parm_reg_stack_loc[regnor] = 0;
4900 parm_reg_stack_loc[regnoi] = 0;
4904 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
4906 /* Mark the register as eliminable if we did no conversion
4907 and it was copied from memory at a fixed offset,
4908 and the arg pointer was not copied to a pseudo-reg.
4909 If the arg pointer is a pseudo reg or the offset formed
4910 an invalid address, such memory-equivalences
4911 as we make here would screw up life analysis for it. */
4912 if (nominal_mode == passed_mode
4915 && GET_CODE (stack_parm) == MEM
4916 && stack_offset.var == 0
4917 && reg_mentioned_p (virtual_incoming_args_rtx,
4918 XEXP (stack_parm, 0)))
4920 rtx linsn = get_last_insn ();
4923 /* Mark complex types separately. */
4924 if (GET_CODE (parmreg) == CONCAT)
4925 /* Scan backwards for the set of the real and
4927 for (sinsn = linsn; sinsn != 0;
4928 sinsn = prev_nonnote_insn (sinsn))
4930 set = single_set (sinsn);
4932 && SET_DEST (set) == regno_reg_rtx [regnoi])
4934 = gen_rtx_EXPR_LIST (REG_EQUIV,
4935 parm_reg_stack_loc[regnoi],
4938 && SET_DEST (set) == regno_reg_rtx [regnor])
4940 = gen_rtx_EXPR_LIST (REG_EQUIV,
4941 parm_reg_stack_loc[regnor],
4944 else if ((set = single_set (linsn)) != 0
4945 && SET_DEST (set) == parmreg)
4947 = gen_rtx_EXPR_LIST (REG_EQUIV,
4948 stack_parm, REG_NOTES (linsn));
4951 /* For pointer data type, suggest pointer register. */
4952 if (POINTER_TYPE_P (TREE_TYPE (parm)))
4953 mark_reg_pointer (parmreg,
4954 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
4956 /* If something wants our address, try to use ADDRESSOF. */
4957 if (TREE_ADDRESSABLE (parm))
4959 /* If we end up putting something into the stack,
4960 fixup_var_refs_insns will need to make a pass over
4961 all the instructions. It looks throughs the pending
4962 sequences -- but it can't see the ones in the
4963 CONVERSION_INSNS, if they're not on the sequence
4964 stack. So, we go back to that sequence, just so that
4965 the fixups will happen. */
4966 push_to_sequence (conversion_insns);
4967 put_var_into_stack (parm);
4968 conversion_insns = get_insns ();
4974 /* Value must be stored in the stack slot STACK_PARM
4975 during function execution. */
4977 if (promoted_mode != nominal_mode)
4979 /* Conversion is required. */
4980 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4982 emit_move_insn (tempreg, validize_mem (entry_parm));
4984 push_to_sequence (conversion_insns);
4985 entry_parm = convert_to_mode (nominal_mode, tempreg,
4986 TREE_UNSIGNED (TREE_TYPE (parm)));
4988 /* ??? This may need a big-endian conversion on sparc64. */
4989 stack_parm = adjust_address (stack_parm, nominal_mode, 0);
4991 conversion_insns = get_insns ();
4996 if (entry_parm != stack_parm)
4998 if (stack_parm == 0)
5001 = assign_stack_local (GET_MODE (entry_parm),
5002 GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
5003 set_mem_attributes (stack_parm, parm, 1);
5006 if (promoted_mode != nominal_mode)
5008 push_to_sequence (conversion_insns);
5009 emit_move_insn (validize_mem (stack_parm),
5010 validize_mem (entry_parm));
5011 conversion_insns = get_insns ();
5015 emit_move_insn (validize_mem (stack_parm),
5016 validize_mem (entry_parm));
5018 if (current_function_check_memory_usage)
5020 push_to_sequence (conversion_insns);
5021 emit_library_call (chkr_set_right_libfunc, LCT_CONST_MAKE_BLOCK,
5022 VOIDmode, 3, XEXP (stack_parm, 0), Pmode,
5023 GEN_INT (GET_MODE_SIZE (GET_MODE
5025 TYPE_MODE (sizetype),
5026 GEN_INT (MEMORY_USE_RW),
5027 TYPE_MODE (integer_type_node));
5029 conversion_insns = get_insns ();
5032 SET_DECL_RTL (parm, stack_parm);
5035 /* If this "parameter" was the place where we are receiving the
5036 function's incoming structure pointer, set up the result. */
5037 if (parm == function_result_decl)
5039 tree result = DECL_RESULT (fndecl);
5040 rtx x = gen_rtx_MEM (DECL_MODE (result), DECL_RTL (parm));
5042 set_mem_attributes (x, result, 1);
5043 SET_DECL_RTL (result, x);
5047 /* Output all parameter conversion instructions (possibly including calls)
5048 now that all parameters have been copied out of hard registers. */
5049 emit_insns (conversion_insns);
5051 last_parm_insn = get_last_insn ();
5053 current_function_args_size = stack_args_size.constant;
5055 /* Adjust function incoming argument size for alignment and
5058 #ifdef REG_PARM_STACK_SPACE
5059 #ifndef MAYBE_REG_PARM_STACK_SPACE
5060 current_function_args_size = MAX (current_function_args_size,
5061 REG_PARM_STACK_SPACE (fndecl));
5065 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
5067 current_function_args_size
5068 = ((current_function_args_size + STACK_BYTES - 1)
5069 / STACK_BYTES) * STACK_BYTES;
5071 #ifdef ARGS_GROW_DOWNWARD
5072 current_function_arg_offset_rtx
5073 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
5074 : expand_expr (size_diffop (stack_args_size.var,
5075 size_int (-stack_args_size.constant)),
5076 NULL_RTX, VOIDmode, EXPAND_MEMORY_USE_BAD));
5078 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
5081 /* See how many bytes, if any, of its args a function should try to pop
5084 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
5085 current_function_args_size);
5087 /* For stdarg.h function, save info about
5088 regs and stack space used by the named args. */
5091 current_function_args_info = args_so_far;
5093 /* Set the rtx used for the function return value. Put this in its
5094 own variable so any optimizers that need this information don't have
5095 to include tree.h. Do this here so it gets done when an inlined
5096 function gets output. */
5098 current_function_return_rtx
5099 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
5100 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
5103 /* Indicate whether REGNO is an incoming argument to the current function
5104 that was promoted to a wider mode. If so, return the RTX for the
5105 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5106 that REGNO is promoted from and whether the promotion was signed or
5109 #ifdef PROMOTE_FUNCTION_ARGS
5112 promoted_input_arg (regno, pmode, punsignedp)
5114 enum machine_mode *pmode;
5119 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
5120 arg = TREE_CHAIN (arg))
5121 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
5122 && REGNO (DECL_INCOMING_RTL (arg)) == regno
5123 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
5125 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
5126 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
5128 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
5129 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
5130 && mode != DECL_MODE (arg))
5132 *pmode = DECL_MODE (arg);
5133 *punsignedp = unsignedp;
5134 return DECL_INCOMING_RTL (arg);
5143 /* Compute the size and offset from the start of the stacked arguments for a
5144 parm passed in mode PASSED_MODE and with type TYPE.
5146 INITIAL_OFFSET_PTR points to the current offset into the stacked
5149 The starting offset and size for this parm are returned in *OFFSET_PTR
5150 and *ARG_SIZE_PTR, respectively.
5152 IN_REGS is non-zero if the argument will be passed in registers. It will
5153 never be set if REG_PARM_STACK_SPACE is not defined.
5155 FNDECL is the function in which the argument was defined.
5157 There are two types of rounding that are done. The first, controlled by
5158 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5159 list to be aligned to the specific boundary (in bits). This rounding
5160 affects the initial and starting offsets, but not the argument size.
5162 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5163 optionally rounds the size of the parm to PARM_BOUNDARY. The
5164 initial offset is not affected by this rounding, while the size always
5165 is and the starting offset may be. */
5167 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
5168 initial_offset_ptr is positive because locate_and_pad_parm's
5169 callers pass in the total size of args so far as
5170 initial_offset_ptr. arg_size_ptr is always positive.*/
5173 locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
5174 initial_offset_ptr, offset_ptr, arg_size_ptr,
5176 enum machine_mode passed_mode;
5178 int in_regs ATTRIBUTE_UNUSED;
5179 tree fndecl ATTRIBUTE_UNUSED;
5180 struct args_size *initial_offset_ptr;
5181 struct args_size *offset_ptr;
5182 struct args_size *arg_size_ptr;
5183 struct args_size *alignment_pad;
5187 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5188 enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5189 int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5191 #ifdef REG_PARM_STACK_SPACE
5192 /* If we have found a stack parm before we reach the end of the
5193 area reserved for registers, skip that area. */
5196 int reg_parm_stack_space = 0;
5198 #ifdef MAYBE_REG_PARM_STACK_SPACE
5199 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
5201 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5203 if (reg_parm_stack_space > 0)
5205 if (initial_offset_ptr->var)
5207 initial_offset_ptr->var
5208 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5209 ssize_int (reg_parm_stack_space));
5210 initial_offset_ptr->constant = 0;
5212 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5213 initial_offset_ptr->constant = reg_parm_stack_space;
5216 #endif /* REG_PARM_STACK_SPACE */
5218 arg_size_ptr->var = 0;
5219 arg_size_ptr->constant = 0;
5220 alignment_pad->var = 0;
5221 alignment_pad->constant = 0;
5223 #ifdef ARGS_GROW_DOWNWARD
5224 if (initial_offset_ptr->var)
5226 offset_ptr->constant = 0;
5227 offset_ptr->var = size_binop (MINUS_EXPR, ssize_int (0),
5228 initial_offset_ptr->var);
5232 offset_ptr->constant = -initial_offset_ptr->constant;
5233 offset_ptr->var = 0;
5235 if (where_pad != none
5236 && (!host_integerp (sizetree, 1)
5237 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5238 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5239 SUB_PARM_SIZE (*offset_ptr, sizetree);
5240 if (where_pad != downward)
5241 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad);
5242 if (initial_offset_ptr->var)
5243 arg_size_ptr->var = size_binop (MINUS_EXPR,
5244 size_binop (MINUS_EXPR,
5246 initial_offset_ptr->var),
5250 arg_size_ptr->constant = (-initial_offset_ptr->constant
5251 - offset_ptr->constant);
5253 #else /* !ARGS_GROW_DOWNWARD */
5255 #ifdef REG_PARM_STACK_SPACE
5256 || REG_PARM_STACK_SPACE (fndecl) > 0
5259 pad_to_arg_alignment (initial_offset_ptr, boundary, alignment_pad);
5260 *offset_ptr = *initial_offset_ptr;
5262 #ifdef PUSH_ROUNDING
5263 if (passed_mode != BLKmode)
5264 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5267 /* Pad_below needs the pre-rounded size to know how much to pad below
5268 so this must be done before rounding up. */
5269 if (where_pad == downward
5270 /* However, BLKmode args passed in regs have their padding done elsewhere.
5271 The stack slot must be able to hold the entire register. */
5272 && !(in_regs && passed_mode == BLKmode))
5273 pad_below (offset_ptr, passed_mode, sizetree);
5275 if (where_pad != none
5276 && (!host_integerp (sizetree, 1)
5277 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5278 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5280 ADD_PARM_SIZE (*arg_size_ptr, sizetree);
5281 #endif /* ARGS_GROW_DOWNWARD */
5284 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5285 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5288 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad)
5289 struct args_size *offset_ptr;
5291 struct args_size *alignment_pad;
5293 tree save_var = NULL_TREE;
5294 HOST_WIDE_INT save_constant = 0;
5296 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5298 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5300 save_var = offset_ptr->var;
5301 save_constant = offset_ptr->constant;
5304 alignment_pad->var = NULL_TREE;
5305 alignment_pad->constant = 0;
5307 if (boundary > BITS_PER_UNIT)
5309 if (offset_ptr->var)
5312 #ifdef ARGS_GROW_DOWNWARD
5317 (ARGS_SIZE_TREE (*offset_ptr),
5318 boundary / BITS_PER_UNIT);
5319 offset_ptr->constant = 0; /*?*/
5320 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5321 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5326 offset_ptr->constant =
5327 #ifdef ARGS_GROW_DOWNWARD
5328 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
5330 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
5332 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5333 alignment_pad->constant = offset_ptr->constant - save_constant;
5338 #ifndef ARGS_GROW_DOWNWARD
5340 pad_below (offset_ptr, passed_mode, sizetree)
5341 struct args_size *offset_ptr;
5342 enum machine_mode passed_mode;
5345 if (passed_mode != BLKmode)
5347 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5348 offset_ptr->constant
5349 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5350 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5351 - GET_MODE_SIZE (passed_mode));
5355 if (TREE_CODE (sizetree) != INTEGER_CST
5356 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5358 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5359 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5361 ADD_PARM_SIZE (*offset_ptr, s2);
5362 SUB_PARM_SIZE (*offset_ptr, sizetree);
5368 /* Walk the tree of blocks describing the binding levels within a function
5369 and warn about uninitialized variables.
5370 This is done after calling flow_analysis and before global_alloc
5371 clobbers the pseudo-regs to hard regs. */
5374 uninitialized_vars_warning (block)
5377 register tree decl, sub;
5378 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5380 if (warn_uninitialized
5381 && TREE_CODE (decl) == VAR_DECL
5382 /* These warnings are unreliable for and aggregates
5383 because assigning the fields one by one can fail to convince
5384 flow.c that the entire aggregate was initialized.
5385 Unions are troublesome because members may be shorter. */
5386 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5387 && DECL_RTL (decl) != 0
5388 && GET_CODE (DECL_RTL (decl)) == REG
5389 /* Global optimizations can make it difficult to determine if a
5390 particular variable has been initialized. However, a VAR_DECL
5391 with a nonzero DECL_INITIAL had an initializer, so do not
5392 claim it is potentially uninitialized.
5394 We do not care about the actual value in DECL_INITIAL, so we do
5395 not worry that it may be a dangling pointer. */
5396 && DECL_INITIAL (decl) == NULL_TREE
5397 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5398 warning_with_decl (decl,
5399 "`%s' might be used uninitialized in this function");
5401 && TREE_CODE (decl) == VAR_DECL
5402 && DECL_RTL (decl) != 0
5403 && GET_CODE (DECL_RTL (decl)) == REG
5404 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5405 warning_with_decl (decl,
5406 "variable `%s' might be clobbered by `longjmp' or `vfork'");
5408 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5409 uninitialized_vars_warning (sub);
5412 /* Do the appropriate part of uninitialized_vars_warning
5413 but for arguments instead of local variables. */
5416 setjmp_args_warning ()
5419 for (decl = DECL_ARGUMENTS (current_function_decl);
5420 decl; decl = TREE_CHAIN (decl))
5421 if (DECL_RTL (decl) != 0
5422 && GET_CODE (DECL_RTL (decl)) == REG
5423 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5424 warning_with_decl (decl,
5425 "argument `%s' might be clobbered by `longjmp' or `vfork'");
5428 /* If this function call setjmp, put all vars into the stack
5429 unless they were declared `register'. */
5432 setjmp_protect (block)
5435 register tree decl, sub;
5436 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5437 if ((TREE_CODE (decl) == VAR_DECL
5438 || TREE_CODE (decl) == PARM_DECL)
5439 && DECL_RTL (decl) != 0
5440 && (GET_CODE (DECL_RTL (decl)) == REG
5441 || (GET_CODE (DECL_RTL (decl)) == MEM
5442 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5443 /* If this variable came from an inline function, it must be
5444 that its life doesn't overlap the setjmp. If there was a
5445 setjmp in the function, it would already be in memory. We
5446 must exclude such variable because their DECL_RTL might be
5447 set to strange things such as virtual_stack_vars_rtx. */
5448 && ! DECL_FROM_INLINE (decl)
5450 #ifdef NON_SAVING_SETJMP
5451 /* If longjmp doesn't restore the registers,
5452 don't put anything in them. */
5456 ! DECL_REGISTER (decl)))
5457 put_var_into_stack (decl);
5458 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5459 setjmp_protect (sub);
5462 /* Like the previous function, but for args instead of local variables. */
5465 setjmp_protect_args ()
5468 for (decl = DECL_ARGUMENTS (current_function_decl);
5469 decl; decl = TREE_CHAIN (decl))
5470 if ((TREE_CODE (decl) == VAR_DECL
5471 || TREE_CODE (decl) == PARM_DECL)
5472 && DECL_RTL (decl) != 0
5473 && (GET_CODE (DECL_RTL (decl)) == REG
5474 || (GET_CODE (DECL_RTL (decl)) == MEM
5475 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5477 /* If longjmp doesn't restore the registers,
5478 don't put anything in them. */
5479 #ifdef NON_SAVING_SETJMP
5483 ! DECL_REGISTER (decl)))
5484 put_var_into_stack (decl);
5487 /* Return the context-pointer register corresponding to DECL,
5488 or 0 if it does not need one. */
5491 lookup_static_chain (decl)
5494 tree context = decl_function_context (decl);
5498 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5501 /* We treat inline_function_decl as an alias for the current function
5502 because that is the inline function whose vars, types, etc.
5503 are being merged into the current function.
5504 See expand_inline_function. */
5505 if (context == current_function_decl || context == inline_function_decl)
5506 return virtual_stack_vars_rtx;
5508 for (link = context_display; link; link = TREE_CHAIN (link))
5509 if (TREE_PURPOSE (link) == context)
5510 return RTL_EXPR_RTL (TREE_VALUE (link));
5515 /* Convert a stack slot address ADDR for variable VAR
5516 (from a containing function)
5517 into an address valid in this function (using a static chain). */
5520 fix_lexical_addr (addr, var)
5525 HOST_WIDE_INT displacement;
5526 tree context = decl_function_context (var);
5527 struct function *fp;
5530 /* If this is the present function, we need not do anything. */
5531 if (context == current_function_decl || context == inline_function_decl)
5534 for (fp = outer_function_chain; fp; fp = fp->next)
5535 if (fp->decl == context)
5541 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5542 addr = XEXP (XEXP (addr, 0), 0);
5544 /* Decode given address as base reg plus displacement. */
5545 if (GET_CODE (addr) == REG)
5546 basereg = addr, displacement = 0;
5547 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5548 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5552 /* We accept vars reached via the containing function's
5553 incoming arg pointer and via its stack variables pointer. */
5554 if (basereg == fp->internal_arg_pointer)
5556 /* If reached via arg pointer, get the arg pointer value
5557 out of that function's stack frame.
5559 There are two cases: If a separate ap is needed, allocate a
5560 slot in the outer function for it and dereference it that way.
5561 This is correct even if the real ap is actually a pseudo.
5562 Otherwise, just adjust the offset from the frame pointer to
5565 #ifdef NEED_SEPARATE_AP
5568 if (fp->x_arg_pointer_save_area == 0)
5569 fp->x_arg_pointer_save_area
5570 = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, fp);
5572 addr = fix_lexical_addr (XEXP (fp->x_arg_pointer_save_area, 0), var);
5573 addr = memory_address (Pmode, addr);
5575 base = gen_rtx_MEM (Pmode, addr);
5576 MEM_ALIAS_SET (base) = get_frame_alias_set ();
5577 base = copy_to_reg (base);
5579 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5580 base = lookup_static_chain (var);
5584 else if (basereg == virtual_stack_vars_rtx)
5586 /* This is the same code as lookup_static_chain, duplicated here to
5587 avoid an extra call to decl_function_context. */
5590 for (link = context_display; link; link = TREE_CHAIN (link))
5591 if (TREE_PURPOSE (link) == context)
5593 base = RTL_EXPR_RTL (TREE_VALUE (link));
5601 /* Use same offset, relative to appropriate static chain or argument
5603 return plus_constant (base, displacement);
5606 /* Return the address of the trampoline for entering nested fn FUNCTION.
5607 If necessary, allocate a trampoline (in the stack frame)
5608 and emit rtl to initialize its contents (at entry to this function). */
5611 trampoline_address (function)
5617 struct function *fp;
5620 /* Find an existing trampoline and return it. */
5621 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5622 if (TREE_PURPOSE (link) == function)
5624 adjust_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5626 for (fp = outer_function_chain; fp; fp = fp->next)
5627 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5628 if (TREE_PURPOSE (link) == function)
5630 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5632 return adjust_trampoline_addr (tramp);
5635 /* None exists; we must make one. */
5637 /* Find the `struct function' for the function containing FUNCTION. */
5639 fn_context = decl_function_context (function);
5640 if (fn_context != current_function_decl
5641 && fn_context != inline_function_decl)
5642 for (fp = outer_function_chain; fp; fp = fp->next)
5643 if (fp->decl == fn_context)
5646 /* Allocate run-time space for this trampoline
5647 (usually in the defining function's stack frame). */
5648 #ifdef ALLOCATE_TRAMPOLINE
5649 tramp = ALLOCATE_TRAMPOLINE (fp);
5651 /* If rounding needed, allocate extra space
5652 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5653 #ifdef TRAMPOLINE_ALIGNMENT
5654 #define TRAMPOLINE_REAL_SIZE \
5655 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5657 #define TRAMPOLINE_REAL_SIZE (TRAMPOLINE_SIZE)
5659 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5663 /* Record the trampoline for reuse and note it for later initialization
5664 by expand_function_end. */
5667 rtlexp = make_node (RTL_EXPR);
5668 RTL_EXPR_RTL (rtlexp) = tramp;
5669 fp->x_trampoline_list = tree_cons (function, rtlexp,
5670 fp->x_trampoline_list);
5674 /* Make the RTL_EXPR node temporary, not momentary, so that the
5675 trampoline_list doesn't become garbage. */
5676 rtlexp = make_node (RTL_EXPR);
5678 RTL_EXPR_RTL (rtlexp) = tramp;
5679 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5682 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5683 return adjust_trampoline_addr (tramp);
5686 /* Given a trampoline address,
5687 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5690 round_trampoline_addr (tramp)
5693 #ifdef TRAMPOLINE_ALIGNMENT
5694 /* Round address up to desired boundary. */
5695 rtx temp = gen_reg_rtx (Pmode);
5696 temp = expand_binop (Pmode, add_optab, tramp,
5697 GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1),
5698 temp, 0, OPTAB_LIB_WIDEN);
5699 tramp = expand_binop (Pmode, and_optab, temp,
5700 GEN_INT (-TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT),
5701 temp, 0, OPTAB_LIB_WIDEN);
5706 /* Given a trampoline address, round it then apply any
5707 platform-specific adjustments so that the result can be used for a
5711 adjust_trampoline_addr (tramp)
5714 tramp = round_trampoline_addr (tramp);
5715 #ifdef TRAMPOLINE_ADJUST_ADDRESS
5716 TRAMPOLINE_ADJUST_ADDRESS (tramp);
5721 /* Put all this function's BLOCK nodes including those that are chained
5722 onto the first block into a vector, and return it.
5723 Also store in each NOTE for the beginning or end of a block
5724 the index of that block in the vector.
5725 The arguments are BLOCK, the chain of top-level blocks of the function,
5726 and INSNS, the insn chain of the function. */
5732 tree *block_vector, *last_block_vector;
5734 tree block = DECL_INITIAL (current_function_decl);
5739 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5740 depth-first order. */
5741 block_vector = get_block_vector (block, &n_blocks);
5742 block_stack = (tree *) xmalloc (n_blocks * sizeof (tree));
5744 last_block_vector = identify_blocks_1 (get_insns (),
5746 block_vector + n_blocks,
5749 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5750 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5751 if (0 && last_block_vector != block_vector + n_blocks)
5754 free (block_vector);
5758 /* Subroutine of identify_blocks. Do the block substitution on the
5759 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
5761 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5762 BLOCK_VECTOR is incremented for each block seen. */
5765 identify_blocks_1 (insns, block_vector, end_block_vector, orig_block_stack)
5768 tree *end_block_vector;
5769 tree *orig_block_stack;
5772 tree *block_stack = orig_block_stack;
5774 for (insn = insns; insn; insn = NEXT_INSN (insn))
5776 if (GET_CODE (insn) == NOTE)
5778 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5782 /* If there are more block notes than BLOCKs, something
5784 if (block_vector == end_block_vector)
5787 b = *block_vector++;
5788 NOTE_BLOCK (insn) = b;
5791 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5793 /* If there are more NOTE_INSN_BLOCK_ENDs than
5794 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
5795 if (block_stack == orig_block_stack)
5798 NOTE_BLOCK (insn) = *--block_stack;
5801 else if (GET_CODE (insn) == CALL_INSN
5802 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5804 rtx cp = PATTERN (insn);
5806 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
5807 end_block_vector, block_stack);
5809 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
5810 end_block_vector, block_stack);
5812 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
5813 end_block_vector, block_stack);
5817 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
5818 something is badly wrong. */
5819 if (block_stack != orig_block_stack)
5822 return block_vector;
5825 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
5826 and create duplicate blocks. */
5827 /* ??? Need an option to either create block fragments or to create
5828 abstract origin duplicates of a source block. It really depends
5829 on what optimization has been performed. */
5834 tree block = DECL_INITIAL (current_function_decl);
5835 varray_type block_stack;
5837 if (block == NULL_TREE)
5840 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
5842 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
5843 reorder_blocks_0 (block);
5845 /* Prune the old trees away, so that they don't get in the way. */
5846 BLOCK_SUBBLOCKS (block) = NULL_TREE;
5847 BLOCK_CHAIN (block) = NULL_TREE;
5849 /* Recreate the block tree from the note nesting. */
5850 reorder_blocks_1 (get_insns (), block, &block_stack);
5851 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
5853 /* Remove deleted blocks from the block fragment chains. */
5854 reorder_fix_fragments (block);
5856 VARRAY_FREE (block_stack);
5859 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
5862 reorder_blocks_0 (block)
5867 TREE_ASM_WRITTEN (block) = 0;
5868 reorder_blocks_0 (BLOCK_SUBBLOCKS (block));
5869 block = BLOCK_CHAIN (block);
5874 reorder_blocks_1 (insns, current_block, p_block_stack)
5877 varray_type *p_block_stack;
5881 for (insn = insns; insn; insn = NEXT_INSN (insn))
5883 if (GET_CODE (insn) == NOTE)
5885 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5887 tree block = NOTE_BLOCK (insn);
5889 /* If we have seen this block before, that means it now
5890 spans multiple address regions. Create a new fragment. */
5891 if (TREE_ASM_WRITTEN (block))
5893 tree new_block = copy_node (block);
5896 origin = (BLOCK_FRAGMENT_ORIGIN (block)
5897 ? BLOCK_FRAGMENT_ORIGIN (block)
5899 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
5900 BLOCK_FRAGMENT_CHAIN (new_block)
5901 = BLOCK_FRAGMENT_CHAIN (origin);
5902 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
5904 NOTE_BLOCK (insn) = new_block;
5908 BLOCK_SUBBLOCKS (block) = 0;
5909 TREE_ASM_WRITTEN (block) = 1;
5910 BLOCK_SUPERCONTEXT (block) = current_block;
5911 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
5912 BLOCK_SUBBLOCKS (current_block) = block;
5913 current_block = block;
5914 VARRAY_PUSH_TREE (*p_block_stack, block);
5916 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5918 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
5919 VARRAY_POP (*p_block_stack);
5920 BLOCK_SUBBLOCKS (current_block)
5921 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5922 current_block = BLOCK_SUPERCONTEXT (current_block);
5925 else if (GET_CODE (insn) == CALL_INSN
5926 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5928 rtx cp = PATTERN (insn);
5929 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
5931 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
5933 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
5938 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
5939 appears in the block tree, select one of the fragments to become
5940 the new origin block. */
5943 reorder_fix_fragments (block)
5948 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
5949 tree new_origin = NULL_TREE;
5953 if (! TREE_ASM_WRITTEN (dup_origin))
5955 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
5957 /* Find the first of the remaining fragments. There must
5958 be at least one -- the current block. */
5959 while (! TREE_ASM_WRITTEN (new_origin))
5960 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
5961 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
5964 else if (! dup_origin)
5967 /* Re-root the rest of the fragments to the new origin. In the
5968 case that DUP_ORIGIN was null, that means BLOCK was the origin
5969 of a chain of fragments and we want to remove those fragments
5970 that didn't make it to the output. */
5973 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
5978 if (TREE_ASM_WRITTEN (chain))
5980 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
5982 pp = &BLOCK_FRAGMENT_CHAIN (chain);
5984 chain = BLOCK_FRAGMENT_CHAIN (chain);
5989 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
5990 block = BLOCK_CHAIN (block);
5994 /* Reverse the order of elements in the chain T of blocks,
5995 and return the new head of the chain (old last element). */
6001 register tree prev = 0, decl, next;
6002 for (decl = t; decl; decl = next)
6004 next = BLOCK_CHAIN (decl);
6005 BLOCK_CHAIN (decl) = prev;
6011 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
6012 non-NULL, list them all into VECTOR, in a depth-first preorder
6013 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
6017 all_blocks (block, vector)
6025 TREE_ASM_WRITTEN (block) = 0;
6027 /* Record this block. */
6029 vector[n_blocks] = block;
6033 /* Record the subblocks, and their subblocks... */
6034 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
6035 vector ? vector + n_blocks : 0);
6036 block = BLOCK_CHAIN (block);
6042 /* Return a vector containing all the blocks rooted at BLOCK. The
6043 number of elements in the vector is stored in N_BLOCKS_P. The
6044 vector is dynamically allocated; it is the caller's responsibility
6045 to call `free' on the pointer returned. */
6048 get_block_vector (block, n_blocks_p)
6054 *n_blocks_p = all_blocks (block, NULL);
6055 block_vector = (tree *) xmalloc (*n_blocks_p * sizeof (tree));
6056 all_blocks (block, block_vector);
6058 return block_vector;
6061 static int next_block_index = 2;
6063 /* Set BLOCK_NUMBER for all the blocks in FN. */
6073 /* For SDB and XCOFF debugging output, we start numbering the blocks
6074 from 1 within each function, rather than keeping a running
6076 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6077 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
6078 next_block_index = 1;
6081 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
6083 /* The top-level BLOCK isn't numbered at all. */
6084 for (i = 1; i < n_blocks; ++i)
6085 /* We number the blocks from two. */
6086 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
6088 free (block_vector);
6093 /* Allocate a function structure and reset its contents to the defaults. */
6095 prepare_function_start ()
6097 cfun = (struct function *) xcalloc (1, sizeof (struct function));
6099 init_stmt_for_function ();
6100 init_eh_for_function ();
6102 cse_not_expected = ! optimize;
6104 /* Caller save not needed yet. */
6105 caller_save_needed = 0;
6107 /* No stack slots have been made yet. */
6108 stack_slot_list = 0;
6110 current_function_has_nonlocal_label = 0;
6111 current_function_has_nonlocal_goto = 0;
6113 /* There is no stack slot for handling nonlocal gotos. */
6114 nonlocal_goto_handler_slots = 0;
6115 nonlocal_goto_stack_level = 0;
6117 /* No labels have been declared for nonlocal use. */
6118 nonlocal_labels = 0;
6119 nonlocal_goto_handler_labels = 0;
6121 /* No function calls so far in this function. */
6122 function_call_count = 0;
6124 /* No parm regs have been allocated.
6125 (This is important for output_inline_function.) */
6126 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
6128 /* Initialize the RTL mechanism. */
6131 /* Initialize the queue of pending postincrement and postdecrements,
6132 and some other info in expr.c. */
6135 /* We haven't done register allocation yet. */
6138 init_varasm_status (cfun);
6140 /* Clear out data used for inlining. */
6141 cfun->inlinable = 0;
6142 cfun->original_decl_initial = 0;
6143 cfun->original_arg_vector = 0;
6145 cfun->stack_alignment_needed = STACK_BOUNDARY;
6146 cfun->preferred_stack_boundary = STACK_BOUNDARY;
6148 /* Set if a call to setjmp is seen. */
6149 current_function_calls_setjmp = 0;
6151 /* Set if a call to longjmp is seen. */
6152 current_function_calls_longjmp = 0;
6154 current_function_calls_alloca = 0;
6155 current_function_contains_functions = 0;
6156 current_function_is_leaf = 0;
6157 current_function_nothrow = 0;
6158 current_function_sp_is_unchanging = 0;
6159 current_function_uses_only_leaf_regs = 0;
6160 current_function_has_computed_jump = 0;
6161 current_function_is_thunk = 0;
6163 current_function_returns_pcc_struct = 0;
6164 current_function_returns_struct = 0;
6165 current_function_epilogue_delay_list = 0;
6166 current_function_uses_const_pool = 0;
6167 current_function_uses_pic_offset_table = 0;
6168 current_function_cannot_inline = 0;
6170 /* We have not yet needed to make a label to jump to for tail-recursion. */
6171 tail_recursion_label = 0;
6173 /* We haven't had a need to make a save area for ap yet. */
6174 arg_pointer_save_area = 0;
6176 /* No stack slots allocated yet. */
6179 /* No SAVE_EXPRs in this function yet. */
6182 /* No RTL_EXPRs in this function yet. */
6185 /* Set up to allocate temporaries. */
6188 /* Indicate that we need to distinguish between the return value of the
6189 present function and the return value of a function being called. */
6190 rtx_equal_function_value_matters = 1;
6192 /* Indicate that we have not instantiated virtual registers yet. */
6193 virtuals_instantiated = 0;
6195 /* Indicate that we want CONCATs now. */
6196 generating_concat_p = 1;
6198 /* Indicate we have no need of a frame pointer yet. */
6199 frame_pointer_needed = 0;
6201 /* By default assume not varargs or stdarg. */
6202 current_function_varargs = 0;
6203 current_function_stdarg = 0;
6205 /* We haven't made any trampolines for this function yet. */
6206 trampoline_list = 0;
6208 init_pending_stack_adjust ();
6209 inhibit_defer_pop = 0;
6211 current_function_outgoing_args_size = 0;
6213 if (init_lang_status)
6214 (*init_lang_status) (cfun);
6215 if (init_machine_status)
6216 (*init_machine_status) (cfun);
6219 /* Initialize the rtl expansion mechanism so that we can do simple things
6220 like generate sequences. This is used to provide a context during global
6221 initialization of some passes. */
6223 init_dummy_function_start ()
6225 prepare_function_start ();
6228 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6229 and initialize static variables for generating RTL for the statements
6233 init_function_start (subr, filename, line)
6235 const char *filename;
6238 prepare_function_start ();
6240 /* Remember this function for later. */
6241 cfun->next_global = all_functions;
6242 all_functions = cfun;
6244 current_function_name = (*decl_printable_name) (subr, 2);
6247 /* Nonzero if this is a nested function that uses a static chain. */
6249 current_function_needs_context
6250 = (decl_function_context (current_function_decl) != 0
6251 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
6253 /* Within function body, compute a type's size as soon it is laid out. */
6254 immediate_size_expand++;
6256 /* Prevent ever trying to delete the first instruction of a function.
6257 Also tell final how to output a linenum before the function prologue.
6258 Note linenums could be missing, e.g. when compiling a Java .class file. */
6260 emit_line_note (filename, line);
6262 /* Make sure first insn is a note even if we don't want linenums.
6263 This makes sure the first insn will never be deleted.
6264 Also, final expects a note to appear there. */
6265 emit_note (NULL, NOTE_INSN_DELETED);
6267 /* Set flags used by final.c. */
6268 if (aggregate_value_p (DECL_RESULT (subr)))
6270 #ifdef PCC_STATIC_STRUCT_RETURN
6271 current_function_returns_pcc_struct = 1;
6273 current_function_returns_struct = 1;
6276 /* Warn if this value is an aggregate type,
6277 regardless of which calling convention we are using for it. */
6278 if (warn_aggregate_return
6279 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6280 warning ("function returns an aggregate");
6282 current_function_returns_pointer
6283 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
6286 /* Make sure all values used by the optimization passes have sane
6289 init_function_for_compilation ()
6293 /* No prologue/epilogue insns yet. */
6294 VARRAY_GROW (prologue, 0);
6295 VARRAY_GROW (epilogue, 0);
6296 VARRAY_GROW (sibcall_epilogue, 0);
6299 /* Indicate that the current function uses extra args
6300 not explicitly mentioned in the argument list in any fashion. */
6305 current_function_varargs = 1;
6308 /* Expand a call to __main at the beginning of a possible main function. */
6310 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6311 #undef HAS_INIT_SECTION
6312 #define HAS_INIT_SECTION
6316 expand_main_function ()
6318 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
6319 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
6321 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
6324 /* Forcably align the stack. */
6325 #ifdef STACK_GROWS_DOWNWARD
6326 tmp = expand_binop (Pmode, and_optab, stack_pointer_rtx,
6327 GEN_INT (-align), stack_pointer_rtx, 1, OPTAB_WIDEN);
6329 tmp = expand_binop (Pmode, add_optab, stack_pointer_rtx,
6330 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
6331 tmp = expand_binop (Pmode, and_optab, tmp, GEN_INT (-align),
6332 stack_pointer_rtx, 1, OPTAB_WIDEN);
6334 if (tmp != stack_pointer_rtx)
6335 emit_move_insn (stack_pointer_rtx, tmp);
6337 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
6338 tmp = force_reg (Pmode, const0_rtx);
6339 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
6343 #ifndef HAS_INIT_SECTION
6344 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, NAME__MAIN), 0,
6349 extern struct obstack permanent_obstack;
6351 /* The PENDING_SIZES represent the sizes of variable-sized types.
6352 Create RTL for the various sizes now (using temporary variables),
6353 so that we can refer to the sizes from the RTL we are generating
6354 for the current function. The PENDING_SIZES are a TREE_LIST. The
6355 TREE_VALUE of each node is a SAVE_EXPR. */
6358 expand_pending_sizes (pending_sizes)
6363 /* Evaluate now the sizes of any types declared among the arguments. */
6364 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
6366 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode,
6367 EXPAND_MEMORY_USE_BAD);
6368 /* Flush the queue in case this parameter declaration has
6374 /* Start the RTL for a new function, and set variables used for
6376 SUBR is the FUNCTION_DECL node.
6377 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6378 the function's parameters, which must be run at any return statement. */
6381 expand_function_start (subr, parms_have_cleanups)
6383 int parms_have_cleanups;
6386 rtx last_ptr = NULL_RTX;
6388 /* Make sure volatile mem refs aren't considered
6389 valid operands of arithmetic insns. */
6390 init_recog_no_volatile ();
6392 /* Set this before generating any memory accesses. */
6393 current_function_check_memory_usage
6394 = (flag_check_memory_usage
6395 && ! DECL_NO_CHECK_MEMORY_USAGE (current_function_decl));
6397 current_function_instrument_entry_exit
6398 = (flag_instrument_function_entry_exit
6399 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6401 current_function_limit_stack
6402 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6404 /* If function gets a static chain arg, store it in the stack frame.
6405 Do this first, so it gets the first stack slot offset. */
6406 if (current_function_needs_context)
6408 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
6410 /* Delay copying static chain if it is not a register to avoid
6411 conflicts with regs used for parameters. */
6412 if (! SMALL_REGISTER_CLASSES
6413 || GET_CODE (static_chain_incoming_rtx) == REG)
6414 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6417 /* If the parameters of this function need cleaning up, get a label
6418 for the beginning of the code which executes those cleanups. This must
6419 be done before doing anything with return_label. */
6420 if (parms_have_cleanups)
6421 cleanup_label = gen_label_rtx ();
6425 /* Make the label for return statements to jump to. Do not special
6426 case machines with special return instructions -- they will be
6427 handled later during jump, ifcvt, or epilogue creation. */
6428 return_label = gen_label_rtx ();
6430 /* Initialize rtx used to return the value. */
6431 /* Do this before assign_parms so that we copy the struct value address
6432 before any library calls that assign parms might generate. */
6434 /* Decide whether to return the value in memory or in a register. */
6435 if (aggregate_value_p (DECL_RESULT (subr)))
6437 /* Returning something that won't go in a register. */
6438 register rtx value_address = 0;
6440 #ifdef PCC_STATIC_STRUCT_RETURN
6441 if (current_function_returns_pcc_struct)
6443 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6444 value_address = assemble_static_space (size);
6449 /* Expect to be passed the address of a place to store the value.
6450 If it is passed as an argument, assign_parms will take care of
6452 if (struct_value_incoming_rtx)
6454 value_address = gen_reg_rtx (Pmode);
6455 emit_move_insn (value_address, struct_value_incoming_rtx);
6460 rtx x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
6461 set_mem_attributes (x, DECL_RESULT (subr), 1);
6462 SET_DECL_RTL (DECL_RESULT (subr), x);
6465 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6466 /* If return mode is void, this decl rtl should not be used. */
6467 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
6470 /* Compute the return values into a pseudo reg, which we will copy
6471 into the true return register after the cleanups are done. */
6473 /* In order to figure out what mode to use for the pseudo, we
6474 figure out what the mode of the eventual return register will
6475 actually be, and use that. */
6477 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
6480 /* Structures that are returned in registers are not aggregate_value_p,
6481 so we may see a PARALLEL. Don't play pseudo games with this. */
6482 if (! REG_P (hard_reg))
6483 SET_DECL_RTL (DECL_RESULT (subr), hard_reg);
6486 /* Create the pseudo. */
6487 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg)));
6489 /* Needed because we may need to move this to memory
6490 in case it's a named return value whose address is taken. */
6491 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6495 /* Initialize rtx for parameters and local variables.
6496 In some cases this requires emitting insns. */
6498 assign_parms (subr);
6500 /* Copy the static chain now if it wasn't a register. The delay is to
6501 avoid conflicts with the parameter passing registers. */
6503 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6504 if (GET_CODE (static_chain_incoming_rtx) != REG)
6505 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6507 /* The following was moved from init_function_start.
6508 The move is supposed to make sdb output more accurate. */
6509 /* Indicate the beginning of the function body,
6510 as opposed to parm setup. */
6511 emit_note (NULL, NOTE_INSN_FUNCTION_BEG);
6513 if (GET_CODE (get_last_insn ()) != NOTE)
6514 emit_note (NULL, NOTE_INSN_DELETED);
6515 parm_birth_insn = get_last_insn ();
6517 context_display = 0;
6518 if (current_function_needs_context)
6520 /* Fetch static chain values for containing functions. */
6521 tem = decl_function_context (current_function_decl);
6522 /* Copy the static chain pointer into a pseudo. If we have
6523 small register classes, copy the value from memory if
6524 static_chain_incoming_rtx is a REG. */
6527 /* If the static chain originally came in a register, put it back
6528 there, then move it out in the next insn. The reason for
6529 this peculiar code is to satisfy function integration. */
6530 if (SMALL_REGISTER_CLASSES
6531 && GET_CODE (static_chain_incoming_rtx) == REG)
6532 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6533 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6538 tree rtlexp = make_node (RTL_EXPR);
6540 RTL_EXPR_RTL (rtlexp) = last_ptr;
6541 context_display = tree_cons (tem, rtlexp, context_display);
6542 tem = decl_function_context (tem);
6545 /* Chain thru stack frames, assuming pointer to next lexical frame
6546 is found at the place we always store it. */
6547 #ifdef FRAME_GROWS_DOWNWARD
6548 last_ptr = plus_constant (last_ptr,
6549 -(HOST_WIDE_INT) GET_MODE_SIZE (Pmode));
6551 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr));
6552 MEM_ALIAS_SET (last_ptr) = get_frame_alias_set ();
6553 last_ptr = copy_to_reg (last_ptr);
6555 /* If we are not optimizing, ensure that we know that this
6556 piece of context is live over the entire function. */
6558 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6563 if (current_function_instrument_entry_exit)
6565 rtx fun = DECL_RTL (current_function_decl);
6566 if (GET_CODE (fun) == MEM)
6567 fun = XEXP (fun, 0);
6570 emit_library_call (profile_function_entry_libfunc, 0, VOIDmode, 2,
6572 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6574 hard_frame_pointer_rtx),
6580 PROFILE_HOOK (profile_label_no);
6583 /* After the display initializations is where the tail-recursion label
6584 should go, if we end up needing one. Ensure we have a NOTE here
6585 since some things (like trampolines) get placed before this. */
6586 tail_recursion_reentry = emit_note (NULL, NOTE_INSN_DELETED);
6588 /* Evaluate now the sizes of any types declared among the arguments. */
6589 expand_pending_sizes (nreverse (get_pending_sizes ()));
6591 /* Make sure there is a line number after the function entry setup code. */
6592 force_next_line_note ();
6595 /* Undo the effects of init_dummy_function_start. */
6597 expand_dummy_function_end ()
6599 /* End any sequences that failed to be closed due to syntax errors. */
6600 while (in_sequence_p ())
6603 /* Outside function body, can't compute type's actual size
6604 until next function's body starts. */
6606 free_after_parsing (cfun);
6607 free_after_compilation (cfun);
6612 /* Call DOIT for each hard register used as a return value from
6613 the current function. */
6616 diddle_return_value (doit, arg)
6617 void (*doit) PARAMS ((rtx, void *));
6620 rtx outgoing = current_function_return_rtx;
6625 if (GET_CODE (outgoing) == REG)
6626 (*doit) (outgoing, arg);
6627 else if (GET_CODE (outgoing) == PARALLEL)
6631 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6633 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6635 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6642 do_clobber_return_reg (reg, arg)
6644 void *arg ATTRIBUTE_UNUSED;
6646 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6650 clobber_return_register ()
6652 diddle_return_value (do_clobber_return_reg, NULL);
6654 /* In case we do use pseudo to return value, clobber it too. */
6655 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6657 tree decl_result = DECL_RESULT (current_function_decl);
6658 rtx decl_rtl = DECL_RTL (decl_result);
6659 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
6661 do_clobber_return_reg (decl_rtl, NULL);
6667 do_use_return_reg (reg, arg)
6669 void *arg ATTRIBUTE_UNUSED;
6671 emit_insn (gen_rtx_USE (VOIDmode, reg));
6675 use_return_register ()
6677 diddle_return_value (do_use_return_reg, NULL);
6680 /* Generate RTL for the end of the current function.
6681 FILENAME and LINE are the current position in the source file.
6683 It is up to language-specific callers to do cleanups for parameters--
6684 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
6687 expand_function_end (filename, line, end_bindings)
6688 const char *filename;
6695 #ifdef TRAMPOLINE_TEMPLATE
6696 static rtx initial_trampoline;
6699 finish_expr_for_function ();
6701 #ifdef NON_SAVING_SETJMP
6702 /* Don't put any variables in registers if we call setjmp
6703 on a machine that fails to restore the registers. */
6704 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6706 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6707 setjmp_protect (DECL_INITIAL (current_function_decl));
6709 setjmp_protect_args ();
6713 /* Save the argument pointer if a save area was made for it. */
6714 if (arg_pointer_save_area)
6716 /* arg_pointer_save_area may not be a valid memory address, so we
6717 have to check it and fix it if necessary. */
6720 emit_move_insn (validize_mem (arg_pointer_save_area),
6721 virtual_incoming_args_rtx);
6722 seq = gen_sequence ();
6724 emit_insn_before (seq, tail_recursion_reentry);
6727 /* Initialize any trampolines required by this function. */
6728 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6730 tree function = TREE_PURPOSE (link);
6731 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6732 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6733 #ifdef TRAMPOLINE_TEMPLATE
6738 #ifdef TRAMPOLINE_TEMPLATE
6739 /* First make sure this compilation has a template for
6740 initializing trampolines. */
6741 if (initial_trampoline == 0)
6744 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6746 ggc_add_rtx_root (&initial_trampoline, 1);
6750 /* Generate insns to initialize the trampoline. */
6752 tramp = round_trampoline_addr (XEXP (tramp, 0));
6753 #ifdef TRAMPOLINE_TEMPLATE
6754 blktramp = change_address (initial_trampoline, BLKmode, tramp);
6755 emit_block_move (blktramp, initial_trampoline,
6756 GEN_INT (TRAMPOLINE_SIZE),
6757 TRAMPOLINE_ALIGNMENT);
6759 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6763 /* Put those insns at entry to the containing function (this one). */
6764 emit_insns_before (seq, tail_recursion_reentry);
6767 /* If we are doing stack checking and this function makes calls,
6768 do a stack probe at the start of the function to ensure we have enough
6769 space for another stack frame. */
6770 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6774 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6775 if (GET_CODE (insn) == CALL_INSN)
6778 probe_stack_range (STACK_CHECK_PROTECT,
6779 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6782 emit_insns_before (seq, tail_recursion_reentry);
6787 /* Warn about unused parms if extra warnings were specified. */
6788 /* Either ``-W -Wunused'' or ``-Wunused-parameter'' enables this
6789 warning. WARN_UNUSED_PARAMETER is negative when set by
6791 if (warn_unused_parameter > 0
6792 || (warn_unused_parameter < 0 && extra_warnings))
6796 for (decl = DECL_ARGUMENTS (current_function_decl);
6797 decl; decl = TREE_CHAIN (decl))
6798 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6799 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6800 warning_with_decl (decl, "unused parameter `%s'");
6803 /* Delete handlers for nonlocal gotos if nothing uses them. */
6804 if (nonlocal_goto_handler_slots != 0
6805 && ! current_function_has_nonlocal_label)
6808 /* End any sequences that failed to be closed due to syntax errors. */
6809 while (in_sequence_p ())
6812 /* Outside function body, can't compute type's actual size
6813 until next function's body starts. */
6814 immediate_size_expand--;
6816 clear_pending_stack_adjust ();
6817 do_pending_stack_adjust ();
6819 /* Mark the end of the function body.
6820 If control reaches this insn, the function can drop through
6821 without returning a value. */
6822 emit_note (NULL, NOTE_INSN_FUNCTION_END);
6824 /* Must mark the last line number note in the function, so that the test
6825 coverage code can avoid counting the last line twice. This just tells
6826 the code to ignore the immediately following line note, since there
6827 already exists a copy of this note somewhere above. This line number
6828 note is still needed for debugging though, so we can't delete it. */
6829 if (flag_test_coverage)
6830 emit_note (NULL, NOTE_INSN_REPEATED_LINE_NUMBER);
6832 /* Output a linenumber for the end of the function.
6833 SDB depends on this. */
6834 emit_line_note_force (filename, line);
6836 /* Before the return label (if any), clobber the return
6837 registers so that they are not propogated live to the rest of
6838 the function. This can only happen with functions that drop
6839 through; if there had been a return statement, there would
6840 have either been a return rtx, or a jump to the return label.
6842 We delay actual code generation after the current_function_value_rtx
6844 clobber_after = get_last_insn ();
6846 /* Output the label for the actual return from the function,
6847 if one is expected. This happens either because a function epilogue
6848 is used instead of a return instruction, or because a return was done
6849 with a goto in order to run local cleanups, or because of pcc-style
6850 structure returning. */
6852 emit_label (return_label);
6854 /* C++ uses this. */
6856 expand_end_bindings (0, 0, 0);
6858 if (current_function_instrument_entry_exit)
6860 rtx fun = DECL_RTL (current_function_decl);
6861 if (GET_CODE (fun) == MEM)
6862 fun = XEXP (fun, 0);
6865 emit_library_call (profile_function_exit_libfunc, 0, VOIDmode, 2,
6867 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6869 hard_frame_pointer_rtx),
6873 /* Let except.c know where it should emit the call to unregister
6874 the function context for sjlj exceptions. */
6875 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
6876 sjlj_emit_function_exit_after (get_last_insn ());
6878 /* If we had calls to alloca, and this machine needs
6879 an accurate stack pointer to exit the function,
6880 insert some code to save and restore the stack pointer. */
6881 #ifdef EXIT_IGNORE_STACK
6882 if (! EXIT_IGNORE_STACK)
6884 if (current_function_calls_alloca)
6888 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
6889 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
6892 /* If scalar return value was computed in a pseudo-reg, or was a named
6893 return value that got dumped to the stack, copy that to the hard
6895 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6897 tree decl_result = DECL_RESULT (current_function_decl);
6898 rtx decl_rtl = DECL_RTL (decl_result);
6900 if (REG_P (decl_rtl)
6901 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
6902 : DECL_REGISTER (decl_result))
6906 #ifdef FUNCTION_OUTGOING_VALUE
6907 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
6908 current_function_decl);
6910 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
6911 current_function_decl);
6913 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
6915 /* If this is a BLKmode structure being returned in registers,
6916 then use the mode computed in expand_return. Note that if
6917 decl_rtl is memory, then its mode may have been changed,
6918 but that current_function_return_rtx has not. */
6919 if (GET_MODE (real_decl_rtl) == BLKmode)
6920 PUT_MODE (real_decl_rtl, GET_MODE (current_function_return_rtx));
6922 /* If a named return value dumped decl_return to memory, then
6923 we may need to re-do the PROMOTE_MODE signed/unsigned
6925 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
6927 int unsignedp = TREE_UNSIGNED (TREE_TYPE (decl_result));
6929 #ifdef PROMOTE_FUNCTION_RETURN
6930 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
6934 convert_move (real_decl_rtl, decl_rtl, unsignedp);
6936 else if (GET_CODE (real_decl_rtl) == PARALLEL)
6937 emit_group_load (real_decl_rtl, decl_rtl,
6938 int_size_in_bytes (TREE_TYPE (decl_result)),
6939 TYPE_ALIGN (TREE_TYPE (decl_result)));
6941 emit_move_insn (real_decl_rtl, decl_rtl);
6943 /* The delay slot scheduler assumes that current_function_return_rtx
6944 holds the hard register containing the return value, not a
6945 temporary pseudo. */
6946 current_function_return_rtx = real_decl_rtl;
6950 /* If returning a structure, arrange to return the address of the value
6951 in a place where debuggers expect to find it.
6953 If returning a structure PCC style,
6954 the caller also depends on this value.
6955 And current_function_returns_pcc_struct is not necessarily set. */
6956 if (current_function_returns_struct
6957 || current_function_returns_pcc_struct)
6960 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
6961 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
6962 #ifdef FUNCTION_OUTGOING_VALUE
6964 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
6965 current_function_decl);
6968 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
6971 /* Mark this as a function return value so integrate will delete the
6972 assignment and USE below when inlining this function. */
6973 REG_FUNCTION_VALUE_P (outgoing) = 1;
6975 #ifdef POINTERS_EXTEND_UNSIGNED
6976 /* The address may be ptr_mode and OUTGOING may be Pmode. */
6977 if (GET_MODE (outgoing) != GET_MODE (value_address))
6978 value_address = convert_memory_address (GET_MODE (outgoing),
6982 emit_move_insn (outgoing, value_address);
6984 /* Show return register used to hold result (in this case the address
6986 current_function_return_rtx = outgoing;
6989 /* If this is an implementation of throw, do what's necessary to
6990 communicate between __builtin_eh_return and the epilogue. */
6991 expand_eh_return ();
6993 /* Emit the actual code to clobber return register. */
6998 clobber_return_register ();
6999 seq = gen_sequence ();
7002 after = emit_insn_after (seq, clobber_after);
7004 if (clobber_after != after)
7005 cfun->x_clobber_return_insn = after;
7008 /* ??? This should no longer be necessary since stupid is no longer with
7009 us, but there are some parts of the compiler (eg reload_combine, and
7010 sh mach_dep_reorg) that still try and compute their own lifetime info
7011 instead of using the general framework. */
7012 use_return_register ();
7014 /* Fix up any gotos that jumped out to the outermost
7015 binding level of the function.
7016 Must follow emitting RETURN_LABEL. */
7018 /* If you have any cleanups to do at this point,
7019 and they need to create temporary variables,
7020 then you will lose. */
7021 expand_fixups (get_insns ());
7024 /* Extend a vector that records the INSN_UIDs of INSNS (either a
7025 sequence or a single insn). */
7028 record_insns (insns, vecp)
7032 if (GET_CODE (insns) == SEQUENCE)
7034 int len = XVECLEN (insns, 0);
7035 int i = VARRAY_SIZE (*vecp);
7037 VARRAY_GROW (*vecp, i + len);
7040 VARRAY_INT (*vecp, i) = INSN_UID (XVECEXP (insns, 0, len));
7046 int i = VARRAY_SIZE (*vecp);
7047 VARRAY_GROW (*vecp, i + 1);
7048 VARRAY_INT (*vecp, i) = INSN_UID (insns);
7052 /* Determine how many INSN_UIDs in VEC are part of INSN. */
7055 contains (insn, vec)
7061 if (GET_CODE (insn) == INSN
7062 && GET_CODE (PATTERN (insn)) == SEQUENCE)
7065 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
7066 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7067 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
7073 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7074 if (INSN_UID (insn) == VARRAY_INT (vec, j))
7081 prologue_epilogue_contains (insn)
7084 if (contains (insn, prologue))
7086 if (contains (insn, epilogue))
7092 sibcall_epilogue_contains (insn)
7095 if (sibcall_epilogue)
7096 return contains (insn, sibcall_epilogue);
7101 /* Insert gen_return at the end of block BB. This also means updating
7102 block_for_insn appropriately. */
7105 emit_return_into_block (bb, line_note)
7111 p = NEXT_INSN (bb->end);
7112 end = emit_jump_insn_after (gen_return (), bb->end);
7114 emit_line_note_after (NOTE_SOURCE_FILE (line_note),
7115 NOTE_LINE_NUMBER (line_note), bb->end);
7119 set_block_for_insn (p, bb);
7126 #endif /* HAVE_return */
7128 #ifdef HAVE_epilogue
7130 /* Modify SEQ, a SEQUENCE that is part of the epilogue, to no modifications
7131 to the stack pointer. */
7134 keep_stack_depressed (seq)
7138 rtx sp_from_reg = 0;
7139 int sp_modified_unknown = 0;
7141 /* If the epilogue is just a single instruction, it's OK as is */
7143 if (GET_CODE (seq) != SEQUENCE)
7146 /* Scan all insns in SEQ looking for ones that modified the stack
7147 pointer. Record if it modified the stack pointer by copying it
7148 from the frame pointer or if it modified it in some other way.
7149 Then modify any subsequent stack pointer references to take that
7150 into account. We start by only allowing SP to be copied from a
7151 register (presumably FP) and then be subsequently referenced. */
7153 for (i = 0; i < XVECLEN (seq, 0); i++)
7155 rtx insn = XVECEXP (seq, 0, i);
7157 if (GET_RTX_CLASS (GET_CODE (insn)) != 'i')
7160 if (reg_set_p (stack_pointer_rtx, insn))
7162 rtx set = single_set (insn);
7164 /* If SP is set as a side-effect, we can't support this. */
7168 if (GET_CODE (SET_SRC (set)) == REG)
7169 sp_from_reg = SET_SRC (set);
7171 sp_modified_unknown = 1;
7173 /* Don't allow the SP modification to happen. */
7174 PUT_CODE (insn, NOTE);
7175 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
7176 NOTE_SOURCE_FILE (insn) = 0;
7178 else if (reg_referenced_p (stack_pointer_rtx, PATTERN (insn)))
7180 if (sp_modified_unknown)
7183 else if (sp_from_reg != 0)
7185 = replace_rtx (PATTERN (insn), stack_pointer_rtx, sp_from_reg);
7191 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7192 this into place with notes indicating where the prologue ends and where
7193 the epilogue begins. Update the basic block information when possible. */
7196 thread_prologue_and_epilogue_insns (f)
7197 rtx f ATTRIBUTE_UNUSED;
7202 #ifdef HAVE_prologue
7203 rtx prologue_end = NULL_RTX;
7205 #if defined (HAVE_epilogue) || defined(HAVE_return)
7206 rtx epilogue_end = NULL_RTX;
7209 #ifdef HAVE_prologue
7213 seq = gen_prologue ();
7216 /* Retain a map of the prologue insns. */
7217 if (GET_CODE (seq) != SEQUENCE)
7219 record_insns (seq, &prologue);
7220 prologue_end = emit_note (NULL, NOTE_INSN_PROLOGUE_END);
7222 seq = gen_sequence ();
7225 /* Can't deal with multiple successsors of the entry block
7226 at the moment. Function should always have at least one
7228 if (!ENTRY_BLOCK_PTR->succ || ENTRY_BLOCK_PTR->succ->succ_next)
7231 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
7236 /* If the exit block has no non-fake predecessors, we don't need
7238 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7239 if ((e->flags & EDGE_FAKE) == 0)
7245 if (optimize && HAVE_return)
7247 /* If we're allowed to generate a simple return instruction,
7248 then by definition we don't need a full epilogue. Examine
7249 the block that falls through to EXIT. If it does not
7250 contain any code, examine its predecessors and try to
7251 emit (conditional) return instructions. */
7257 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7258 if (e->flags & EDGE_FALLTHRU)
7264 /* Verify that there are no active instructions in the last block. */
7266 while (label && GET_CODE (label) != CODE_LABEL)
7268 if (active_insn_p (label))
7270 label = PREV_INSN (label);
7273 if (last->head == label && GET_CODE (label) == CODE_LABEL)
7275 rtx epilogue_line_note = NULL_RTX;
7277 /* Locate the line number associated with the closing brace,
7278 if we can find one. */
7279 for (seq = get_last_insn ();
7280 seq && ! active_insn_p (seq);
7281 seq = PREV_INSN (seq))
7282 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
7284 epilogue_line_note = seq;
7288 for (e = last->pred; e; e = e_next)
7290 basic_block bb = e->src;
7293 e_next = e->pred_next;
7294 if (bb == ENTRY_BLOCK_PTR)
7298 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
7301 /* If we have an unconditional jump, we can replace that
7302 with a simple return instruction. */
7303 if (simplejump_p (jump))
7305 emit_return_into_block (bb, epilogue_line_note);
7306 flow_delete_insn (jump);
7309 /* If we have a conditional jump, we can try to replace
7310 that with a conditional return instruction. */
7311 else if (condjump_p (jump))
7315 ret = SET_SRC (PATTERN (jump));
7316 if (GET_CODE (XEXP (ret, 1)) == LABEL_REF)
7317 loc = &XEXP (ret, 1);
7319 loc = &XEXP (ret, 2);
7320 ret = gen_rtx_RETURN (VOIDmode);
7322 if (! validate_change (jump, loc, ret, 0))
7324 if (JUMP_LABEL (jump))
7325 LABEL_NUSES (JUMP_LABEL (jump))--;
7327 /* If this block has only one successor, it both jumps
7328 and falls through to the fallthru block, so we can't
7330 if (bb->succ->succ_next == NULL)
7336 /* Fix up the CFG for the successful change we just made. */
7337 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7340 /* Emit a return insn for the exit fallthru block. Whether
7341 this is still reachable will be determined later. */
7343 emit_barrier_after (last->end);
7344 emit_return_into_block (last, epilogue_line_note);
7345 epilogue_end = last->end;
7350 #ifdef HAVE_epilogue
7353 /* Find the edge that falls through to EXIT. Other edges may exist
7354 due to RETURN instructions, but those don't need epilogues.
7355 There really shouldn't be a mixture -- either all should have
7356 been converted or none, however... */
7358 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7359 if (e->flags & EDGE_FALLTHRU)
7365 epilogue_end = emit_note (NULL, NOTE_INSN_EPILOGUE_BEG);
7367 seq = gen_epilogue ();
7369 /* If this function returns with the stack depressed, massage
7370 the epilogue to actually do that. */
7371 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7372 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7373 keep_stack_depressed (seq);
7375 emit_jump_insn (seq);
7377 /* Retain a map of the epilogue insns. */
7378 if (GET_CODE (seq) != SEQUENCE)
7380 record_insns (seq, &epilogue);
7382 seq = gen_sequence ();
7385 insert_insn_on_edge (seq, e);
7392 commit_edge_insertions ();
7394 #ifdef HAVE_sibcall_epilogue
7395 /* Emit sibling epilogues before any sibling call sites. */
7396 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7398 basic_block bb = e->src;
7403 if (GET_CODE (insn) != CALL_INSN
7404 || ! SIBLING_CALL_P (insn))
7408 seq = gen_sibcall_epilogue ();
7411 i = PREV_INSN (insn);
7412 newinsn = emit_insn_before (seq, insn);
7414 /* Update the UID to basic block map. */
7415 for (i = NEXT_INSN (i); i != insn; i = NEXT_INSN (i))
7416 set_block_for_insn (i, bb);
7418 /* Retain a map of the epilogue insns. Used in life analysis to
7419 avoid getting rid of sibcall epilogue insns. */
7420 record_insns (GET_CODE (seq) == SEQUENCE
7421 ? seq : newinsn, &sibcall_epilogue);
7425 #ifdef HAVE_prologue
7430 /* GDB handles `break f' by setting a breakpoint on the first
7431 line note after the prologue. Which means (1) that if
7432 there are line number notes before where we inserted the
7433 prologue we should move them, and (2) we should generate a
7434 note before the end of the first basic block, if there isn't
7437 ??? This behaviour is completely broken when dealing with
7438 multiple entry functions. We simply place the note always
7439 into first basic block and let alternate entry points
7443 for (insn = prologue_end; insn; insn = prev)
7445 prev = PREV_INSN (insn);
7446 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7448 /* Note that we cannot reorder the first insn in the
7449 chain, since rest_of_compilation relies on that
7450 remaining constant. */
7453 reorder_insns (insn, insn, prologue_end);
7457 /* Find the last line number note in the first block. */
7458 for (insn = BASIC_BLOCK (0)->end;
7459 insn != prologue_end && insn;
7460 insn = PREV_INSN (insn))
7461 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7464 /* If we didn't find one, make a copy of the first line number
7468 for (insn = next_active_insn (prologue_end);
7470 insn = PREV_INSN (insn))
7471 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7473 emit_line_note_after (NOTE_SOURCE_FILE (insn),
7474 NOTE_LINE_NUMBER (insn),
7481 #ifdef HAVE_epilogue
7486 /* Similarly, move any line notes that appear after the epilogue.
7487 There is no need, however, to be quite so anal about the existance
7489 for (insn = epilogue_end; insn; insn = next)
7491 next = NEXT_INSN (insn);
7492 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7493 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7499 /* Reposition the prologue-end and epilogue-begin notes after instruction
7500 scheduling and delayed branch scheduling. */
7503 reposition_prologue_and_epilogue_notes (f)
7504 rtx f ATTRIBUTE_UNUSED;
7506 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7509 if ((len = VARRAY_SIZE (prologue)) > 0)
7511 register rtx insn, note = 0;
7513 /* Scan from the beginning until we reach the last prologue insn.
7514 We apparently can't depend on basic_block_{head,end} after
7516 for (insn = f; len && insn; insn = NEXT_INSN (insn))
7518 if (GET_CODE (insn) == NOTE)
7520 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
7523 else if ((len -= contains (insn, prologue)) == 0)
7526 /* Find the prologue-end note if we haven't already, and
7527 move it to just after the last prologue insn. */
7530 for (note = insn; (note = NEXT_INSN (note));)
7531 if (GET_CODE (note) == NOTE
7532 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
7536 next = NEXT_INSN (note);
7538 /* Whether or not we can depend on BLOCK_HEAD,
7539 attempt to keep it up-to-date. */
7540 if (BLOCK_HEAD (0) == note)
7541 BLOCK_HEAD (0) = next;
7544 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
7545 if (GET_CODE (insn) == CODE_LABEL)
7546 insn = NEXT_INSN (insn);
7547 add_insn_after (note, insn);
7552 if ((len = VARRAY_SIZE (epilogue)) > 0)
7554 register rtx insn, note = 0;
7556 /* Scan from the end until we reach the first epilogue insn.
7557 We apparently can't depend on basic_block_{head,end} after
7559 for (insn = get_last_insn (); len && insn; insn = PREV_INSN (insn))
7561 if (GET_CODE (insn) == NOTE)
7563 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
7566 else if ((len -= contains (insn, epilogue)) == 0)
7568 /* Find the epilogue-begin note if we haven't already, and
7569 move it to just before the first epilogue insn. */
7572 for (note = insn; (note = PREV_INSN (note));)
7573 if (GET_CODE (note) == NOTE
7574 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
7578 /* Whether or not we can depend on BLOCK_HEAD,
7579 attempt to keep it up-to-date. */
7581 && BLOCK_HEAD (n_basic_blocks-1) == insn)
7582 BLOCK_HEAD (n_basic_blocks-1) = note;
7585 add_insn_before (note, insn);
7589 #endif /* HAVE_prologue or HAVE_epilogue */
7592 /* Mark T for GC. */
7596 struct temp_slot *t;
7600 ggc_mark_rtx (t->slot);
7601 ggc_mark_rtx (t->address);
7602 ggc_mark_tree (t->rtl_expr);
7603 ggc_mark_tree (t->type);
7609 /* Mark P for GC. */
7612 mark_function_status (p)
7621 ggc_mark_rtx (p->arg_offset_rtx);
7623 if (p->x_parm_reg_stack_loc)
7624 for (i = p->x_max_parm_reg, r = p->x_parm_reg_stack_loc;
7628 ggc_mark_rtx (p->return_rtx);
7629 ggc_mark_rtx (p->x_cleanup_label);
7630 ggc_mark_rtx (p->x_return_label);
7631 ggc_mark_rtx (p->x_save_expr_regs);
7632 ggc_mark_rtx (p->x_stack_slot_list);
7633 ggc_mark_rtx (p->x_parm_birth_insn);
7634 ggc_mark_rtx (p->x_tail_recursion_label);
7635 ggc_mark_rtx (p->x_tail_recursion_reentry);
7636 ggc_mark_rtx (p->internal_arg_pointer);
7637 ggc_mark_rtx (p->x_arg_pointer_save_area);
7638 ggc_mark_tree (p->x_rtl_expr_chain);
7639 ggc_mark_rtx (p->x_last_parm_insn);
7640 ggc_mark_tree (p->x_context_display);
7641 ggc_mark_tree (p->x_trampoline_list);
7642 ggc_mark_rtx (p->epilogue_delay_list);
7643 ggc_mark_rtx (p->x_clobber_return_insn);
7645 mark_temp_slot (p->x_temp_slots);
7648 struct var_refs_queue *q = p->fixup_var_refs_queue;
7651 ggc_mark_rtx (q->modified);
7656 ggc_mark_rtx (p->x_nonlocal_goto_handler_slots);
7657 ggc_mark_rtx (p->x_nonlocal_goto_handler_labels);
7658 ggc_mark_rtx (p->x_nonlocal_goto_stack_level);
7659 ggc_mark_tree (p->x_nonlocal_labels);
7661 mark_hard_reg_initial_vals (p);
7664 /* Mark the function chain ARG (which is really a struct function **)
7668 mark_function_chain (arg)
7671 struct function *f = *(struct function **) arg;
7673 for (; f; f = f->next_global)
7675 ggc_mark_tree (f->decl);
7677 mark_function_status (f);
7678 mark_eh_status (f->eh);
7679 mark_stmt_status (f->stmt);
7680 mark_expr_status (f->expr);
7681 mark_emit_status (f->emit);
7682 mark_varasm_status (f->varasm);
7684 if (mark_machine_status)
7685 (*mark_machine_status) (f);
7686 if (mark_lang_status)
7687 (*mark_lang_status) (f);
7689 if (f->original_arg_vector)
7690 ggc_mark_rtvec ((rtvec) f->original_arg_vector);
7691 if (f->original_decl_initial)
7692 ggc_mark_tree (f->original_decl_initial);
7696 /* Called once, at initialization, to initialize function.c. */
7699 init_function_once ()
7701 ggc_add_root (&all_functions, 1, sizeof all_functions,
7702 mark_function_chain);
7704 VARRAY_INT_INIT (prologue, 0, "prologue");
7705 VARRAY_INT_INIT (epilogue, 0, "epilogue");
7706 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");