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. */
50 #include "hard-reg-set.h"
51 #include "insn-config.h"
54 #include "basic-block.h"
61 #ifndef TRAMPOLINE_ALIGNMENT
62 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
65 #ifndef LOCAL_ALIGNMENT
66 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
69 #if !defined (PREFERRED_STACK_BOUNDARY) && defined (STACK_BOUNDARY)
70 #define PREFERRED_STACK_BOUNDARY STACK_BOUNDARY
73 /* Some systems use __main in a way incompatible with its use in gcc, in these
74 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
75 give the same symbol without quotes for an alternative entry point. You
76 must define both, or neither. */
78 #define NAME__MAIN "__main"
79 #define SYMBOL__MAIN __main
82 /* Round a value to the lowest integer less than it that is a multiple of
83 the required alignment. Avoid using division in case the value is
84 negative. Assume the alignment is a power of two. */
85 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
87 /* Similar, but round to the next highest integer that meets the
89 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
91 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
92 during rtl generation. If they are different register numbers, this is
93 always true. It may also be true if
94 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
95 generation. See fix_lexical_addr for details. */
97 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
98 #define NEED_SEPARATE_AP
101 /* Nonzero if function being compiled doesn't contain any calls
102 (ignoring the prologue and epilogue). This is set prior to
103 local register allocation and is valid for the remaining
105 int current_function_is_leaf;
107 /* Nonzero if function being compiled doesn't contain any instructions
108 that can throw an exception. This is set prior to final. */
110 int current_function_nothrow;
112 /* Nonzero if function being compiled doesn't modify the stack pointer
113 (ignoring the prologue and epilogue). This is only valid after
114 life_analysis has run. */
115 int current_function_sp_is_unchanging;
117 /* Nonzero if the function being compiled is a leaf function which only
118 uses leaf registers. This is valid after reload (specifically after
119 sched2) and is useful only if the port defines LEAF_REGISTERS. */
120 int current_function_uses_only_leaf_regs;
122 /* Nonzero once virtual register instantiation has been done.
123 assign_stack_local uses frame_pointer_rtx when this is nonzero. */
124 static int virtuals_instantiated;
126 /* These variables hold pointers to functions to create and destroy
127 target specific, per-function data structures. */
128 void (*init_machine_status) PARAMS ((struct function *));
129 void (*free_machine_status) PARAMS ((struct function *));
130 /* This variable holds a pointer to a function to register any
131 data items in the target specific, per-function data structure
132 that will need garbage collection. */
133 void (*mark_machine_status) PARAMS ((struct function *));
135 /* Likewise, but for language-specific data. */
136 void (*init_lang_status) PARAMS ((struct function *));
137 void (*save_lang_status) PARAMS ((struct function *));
138 void (*restore_lang_status) PARAMS ((struct function *));
139 void (*mark_lang_status) PARAMS ((struct function *));
140 void (*free_lang_status) PARAMS ((struct function *));
142 /* The FUNCTION_DECL for an inline function currently being expanded. */
143 tree inline_function_decl;
145 /* The currently compiled function. */
146 struct function *cfun = 0;
148 /* Global list of all compiled functions. */
149 struct function *all_functions = 0;
151 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
152 static varray_type prologue;
153 static varray_type epilogue;
155 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
157 static varray_type sibcall_epilogue;
159 /* In order to evaluate some expressions, such as function calls returning
160 structures in memory, we need to temporarily allocate stack locations.
161 We record each allocated temporary in the following structure.
163 Associated with each temporary slot is a nesting level. When we pop up
164 one level, all temporaries associated with the previous level are freed.
165 Normally, all temporaries are freed after the execution of the statement
166 in which they were created. However, if we are inside a ({...}) grouping,
167 the result may be in a temporary and hence must be preserved. If the
168 result could be in a temporary, we preserve it if we can determine which
169 one it is in. If we cannot determine which temporary may contain the
170 result, all temporaries are preserved. A temporary is preserved by
171 pretending it was allocated at the previous nesting level.
173 Automatic variables are also assigned temporary slots, at the nesting
174 level where they are defined. They are marked a "kept" so that
175 free_temp_slots will not free them. */
179 /* Points to next temporary slot. */
180 struct temp_slot *next;
181 /* The rtx to used to reference the slot. */
183 /* The rtx used to represent the address if not the address of the
184 slot above. May be an EXPR_LIST if multiple addresses exist. */
186 /* The alignment (in bits) of the slot. */
188 /* The size, in units, of the slot. */
190 /* The type of the object in the slot, or zero if it doesn't correspond
191 to a type. We use this to determine whether a slot can be reused.
192 It can be reused if objects of the type of the new slot will always
193 conflict with objects of the type of the old slot. */
195 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
197 /* Non-zero if this temporary is currently in use. */
199 /* Non-zero if this temporary has its address taken. */
201 /* Nesting level at which this slot is being used. */
203 /* Non-zero if this should survive a call to free_temp_slots. */
205 /* The offset of the slot from the frame_pointer, including extra space
206 for alignment. This info is for combine_temp_slots. */
207 HOST_WIDE_INT base_offset;
208 /* The size of the slot, including extra space for alignment. This
209 info is for combine_temp_slots. */
210 HOST_WIDE_INT full_size;
213 /* This structure is used to record MEMs or pseudos used to replace VAR, any
214 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
215 maintain this list in case two operands of an insn were required to match;
216 in that case we must ensure we use the same replacement. */
218 struct fixup_replacement
222 struct fixup_replacement *next;
225 struct insns_for_mem_entry {
226 /* The KEY in HE will be a MEM. */
227 struct hash_entry he;
228 /* These are the INSNS which reference the MEM. */
232 /* Forward declarations. */
234 static rtx assign_stack_local_1 PARAMS ((enum machine_mode, HOST_WIDE_INT,
235 int, struct function *));
236 static rtx assign_stack_temp_for_type PARAMS ((enum machine_mode,
237 HOST_WIDE_INT, int, tree));
238 static struct temp_slot *find_temp_slot_from_address PARAMS ((rtx));
239 static void put_reg_into_stack PARAMS ((struct function *, rtx, tree,
240 enum machine_mode, enum machine_mode,
241 int, unsigned int, int,
242 struct hash_table *));
243 static void schedule_fixup_var_refs PARAMS ((struct function *, rtx, tree,
245 struct hash_table *));
246 static void fixup_var_refs PARAMS ((rtx, enum machine_mode, int,
247 struct hash_table *));
248 static struct fixup_replacement
249 *find_fixup_replacement PARAMS ((struct fixup_replacement **, rtx));
250 static void fixup_var_refs_insns PARAMS ((rtx, rtx, enum machine_mode,
252 static void fixup_var_refs_insns_with_hash
253 PARAMS ((struct hash_table *, rtx,
254 enum machine_mode, int));
255 static void fixup_var_refs_insn PARAMS ((rtx, rtx, enum machine_mode,
257 static void fixup_var_refs_1 PARAMS ((rtx, enum machine_mode, rtx *, rtx,
258 struct fixup_replacement **));
259 static rtx fixup_memory_subreg PARAMS ((rtx, rtx, int));
260 static rtx walk_fixup_memory_subreg PARAMS ((rtx, rtx, int));
261 static rtx fixup_stack_1 PARAMS ((rtx, rtx));
262 static void optimize_bit_field PARAMS ((rtx, rtx, rtx *));
263 static void instantiate_decls PARAMS ((tree, int));
264 static void instantiate_decls_1 PARAMS ((tree, int));
265 static void instantiate_decl PARAMS ((rtx, HOST_WIDE_INT, int));
266 static rtx instantiate_new_reg PARAMS ((rtx, HOST_WIDE_INT *));
267 static int instantiate_virtual_regs_1 PARAMS ((rtx *, rtx, int));
268 static void delete_handlers PARAMS ((void));
269 static void pad_to_arg_alignment PARAMS ((struct args_size *, int,
270 struct args_size *));
271 #ifndef ARGS_GROW_DOWNWARD
272 static void pad_below PARAMS ((struct args_size *, enum machine_mode,
275 static rtx round_trampoline_addr PARAMS ((rtx));
276 static rtx adjust_trampoline_addr PARAMS ((rtx));
277 static tree *identify_blocks_1 PARAMS ((rtx, tree *, tree *, tree *));
278 static void reorder_blocks_0 PARAMS ((rtx));
279 static void reorder_blocks_1 PARAMS ((rtx, tree, varray_type *));
280 static tree blocks_nreverse PARAMS ((tree));
281 static int all_blocks PARAMS ((tree, tree *));
282 static tree *get_block_vector PARAMS ((tree, int *));
283 /* We always define `record_insns' even if its not used so that we
284 can always export `prologue_epilogue_contains'. */
285 static void record_insns PARAMS ((rtx, varray_type *)) ATTRIBUTE_UNUSED;
286 static int contains PARAMS ((rtx, varray_type));
288 static void emit_return_into_block PARAMS ((basic_block, rtx));
290 static void put_addressof_into_stack PARAMS ((rtx, struct hash_table *));
291 static bool purge_addressof_1 PARAMS ((rtx *, rtx, int, int,
292 struct hash_table *));
293 static void purge_single_hard_subreg_set PARAMS ((rtx));
295 static void keep_stack_depressed PARAMS ((rtx));
297 static int is_addressof PARAMS ((rtx *, void *));
298 static struct hash_entry *insns_for_mem_newfunc PARAMS ((struct hash_entry *,
301 static unsigned long insns_for_mem_hash PARAMS ((hash_table_key));
302 static bool insns_for_mem_comp PARAMS ((hash_table_key, hash_table_key));
303 static int insns_for_mem_walk PARAMS ((rtx *, void *));
304 static void compute_insns_for_mem PARAMS ((rtx, rtx, struct hash_table *));
305 static void mark_temp_slot PARAMS ((struct temp_slot *));
306 static void mark_function_status PARAMS ((struct function *));
307 static void mark_function_chain PARAMS ((void *));
308 static void prepare_function_start PARAMS ((void));
309 static void do_clobber_return_reg PARAMS ((rtx, void *));
310 static void do_use_return_reg PARAMS ((rtx, void *));
312 /* Pointer to chain of `struct function' for containing functions. */
313 struct function *outer_function_chain;
315 /* Given a function decl for a containing function,
316 return the `struct function' for it. */
319 find_function_data (decl)
324 for (p = outer_function_chain; p; p = p->next)
331 /* Save the current context for compilation of a nested function.
332 This is called from language-specific code. The caller should use
333 the save_lang_status callback to save any language-specific state,
334 since this function knows only about language-independent
338 push_function_context_to (context)
341 struct function *p, *context_data;
345 context_data = (context == current_function_decl
347 : find_function_data (context));
348 context_data->contains_functions = 1;
352 init_dummy_function_start ();
355 p->next = outer_function_chain;
356 outer_function_chain = p;
357 p->fixup_var_refs_queue = 0;
359 if (save_lang_status)
360 (*save_lang_status) (p);
366 push_function_context ()
368 push_function_context_to (current_function_decl);
371 /* Restore the last saved context, at the end of a nested function.
372 This function is called from language-specific code. */
375 pop_function_context_from (context)
376 tree context ATTRIBUTE_UNUSED;
378 struct function *p = outer_function_chain;
379 struct var_refs_queue *queue;
380 struct var_refs_queue *next;
383 outer_function_chain = p->next;
385 current_function_decl = p->decl;
388 restore_emit_status (p);
390 if (restore_lang_status)
391 (*restore_lang_status) (p);
393 /* Finish doing put_var_into_stack for any of our variables
394 which became addressable during the nested function. */
395 for (queue = p->fixup_var_refs_queue; queue; queue = next)
398 fixup_var_refs (queue->modified, queue->promoted_mode,
399 queue->unsignedp, 0);
402 p->fixup_var_refs_queue = 0;
404 /* Reset variables that have known state during rtx generation. */
405 rtx_equal_function_value_matters = 1;
406 virtuals_instantiated = 0;
407 generating_concat_p = 1;
411 pop_function_context ()
413 pop_function_context_from (current_function_decl);
416 /* Clear out all parts of the state in F that can safely be discarded
417 after the function has been parsed, but not compiled, to let
418 garbage collection reclaim the memory. */
421 free_after_parsing (f)
424 /* f->expr->forced_labels is used by code generation. */
425 /* f->emit->regno_reg_rtx is used by code generation. */
426 /* f->varasm is used by code generation. */
427 /* f->eh->eh_return_stub_label is used by code generation. */
429 if (free_lang_status)
430 (*free_lang_status) (f);
431 free_stmt_status (f);
434 /* Clear out all parts of the state in F that can safely be discarded
435 after the function has been compiled, to let garbage collection
436 reclaim the memory. */
439 free_after_compilation (f)
442 struct temp_slot *ts;
443 struct temp_slot *next;
446 free_expr_status (f);
447 free_emit_status (f);
448 free_varasm_status (f);
450 if (free_machine_status)
451 (*free_machine_status) (f);
453 if (f->x_parm_reg_stack_loc)
454 free (f->x_parm_reg_stack_loc);
456 for (ts = f->x_temp_slots; ts; ts = next)
461 f->x_temp_slots = NULL;
463 f->arg_offset_rtx = NULL;
464 f->return_rtx = NULL;
465 f->internal_arg_pointer = NULL;
466 f->x_nonlocal_labels = NULL;
467 f->x_nonlocal_goto_handler_slots = NULL;
468 f->x_nonlocal_goto_handler_labels = NULL;
469 f->x_nonlocal_goto_stack_level = NULL;
470 f->x_cleanup_label = NULL;
471 f->x_return_label = NULL;
472 f->x_save_expr_regs = NULL;
473 f->x_stack_slot_list = NULL;
474 f->x_rtl_expr_chain = NULL;
475 f->x_tail_recursion_label = NULL;
476 f->x_tail_recursion_reentry = NULL;
477 f->x_arg_pointer_save_area = NULL;
478 f->x_clobber_return_insn = NULL;
479 f->x_context_display = NULL;
480 f->x_trampoline_list = NULL;
481 f->x_parm_birth_insn = NULL;
482 f->x_last_parm_insn = NULL;
483 f->x_parm_reg_stack_loc = NULL;
484 f->fixup_var_refs_queue = NULL;
485 f->original_arg_vector = NULL;
486 f->original_decl_initial = NULL;
487 f->inl_last_parm_insn = NULL;
488 f->epilogue_delay_list = NULL;
491 /* Allocate fixed slots in the stack frame of the current function. */
493 /* Return size needed for stack frame based on slots so far allocated in
495 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
496 the caller may have to do that. */
499 get_func_frame_size (f)
502 #ifdef FRAME_GROWS_DOWNWARD
503 return -f->x_frame_offset;
505 return f->x_frame_offset;
509 /* Return size needed for stack frame based on slots so far allocated.
510 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
511 the caller may have to do that. */
515 return get_func_frame_size (cfun);
518 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
519 with machine mode MODE.
521 ALIGN controls the amount of alignment for the address of the slot:
522 0 means according to MODE,
523 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
524 positive specifies alignment boundary in bits.
526 We do not round to stack_boundary here.
528 FUNCTION specifies the function to allocate in. */
531 assign_stack_local_1 (mode, size, align, function)
532 enum machine_mode mode;
535 struct function *function;
537 register rtx x, addr;
538 int bigend_correction = 0;
546 alignment = BIGGEST_ALIGNMENT;
548 alignment = GET_MODE_ALIGNMENT (mode);
550 /* Allow the target to (possibly) increase the alignment of this
552 type = type_for_mode (mode, 0);
554 alignment = LOCAL_ALIGNMENT (type, alignment);
556 alignment /= BITS_PER_UNIT;
558 else if (align == -1)
560 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
561 size = CEIL_ROUND (size, alignment);
564 alignment = align / BITS_PER_UNIT;
566 #ifdef FRAME_GROWS_DOWNWARD
567 function->x_frame_offset -= size;
570 /* Ignore alignment we can't do with expected alignment of the boundary. */
571 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
572 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
574 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
575 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
577 /* Round frame offset to that alignment.
578 We must be careful here, since FRAME_OFFSET might be negative and
579 division with a negative dividend isn't as well defined as we might
580 like. So we instead assume that ALIGNMENT is a power of two and
581 use logical operations which are unambiguous. */
582 #ifdef FRAME_GROWS_DOWNWARD
583 function->x_frame_offset = FLOOR_ROUND (function->x_frame_offset, alignment);
585 function->x_frame_offset = CEIL_ROUND (function->x_frame_offset, alignment);
588 /* On a big-endian machine, if we are allocating more space than we will use,
589 use the least significant bytes of those that are allocated. */
590 if (BYTES_BIG_ENDIAN && mode != BLKmode)
591 bigend_correction = size - GET_MODE_SIZE (mode);
593 /* If we have already instantiated virtual registers, return the actual
594 address relative to the frame pointer. */
595 if (function == cfun && virtuals_instantiated)
596 addr = plus_constant (frame_pointer_rtx,
597 (frame_offset + bigend_correction
598 + STARTING_FRAME_OFFSET));
600 addr = plus_constant (virtual_stack_vars_rtx,
601 function->x_frame_offset + bigend_correction);
603 #ifndef FRAME_GROWS_DOWNWARD
604 function->x_frame_offset += size;
607 x = gen_rtx_MEM (mode, addr);
609 function->x_stack_slot_list
610 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
615 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
619 assign_stack_local (mode, size, align)
620 enum machine_mode mode;
624 return assign_stack_local_1 (mode, size, align, cfun);
627 /* Allocate a temporary stack slot and record it for possible later
630 MODE is the machine mode to be given to the returned rtx.
632 SIZE is the size in units of the space required. We do no rounding here
633 since assign_stack_local will do any required rounding.
635 KEEP is 1 if this slot is to be retained after a call to
636 free_temp_slots. Automatic variables for a block are allocated
637 with this flag. KEEP is 2 if we allocate a longer term temporary,
638 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
639 if we are to allocate something at an inner level to be treated as
640 a variable in the block (e.g., a SAVE_EXPR).
642 TYPE is the type that will be used for the stack slot. */
645 assign_stack_temp_for_type (mode, size, keep, type)
646 enum machine_mode mode;
652 struct temp_slot *p, *best_p = 0;
654 /* If SIZE is -1 it means that somebody tried to allocate a temporary
655 of a variable size. */
660 align = BIGGEST_ALIGNMENT;
662 align = GET_MODE_ALIGNMENT (mode);
665 type = type_for_mode (mode, 0);
668 align = LOCAL_ALIGNMENT (type, align);
670 /* Try to find an available, already-allocated temporary of the proper
671 mode which meets the size and alignment requirements. Choose the
672 smallest one with the closest alignment. */
673 for (p = temp_slots; p; p = p->next)
674 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
676 && objects_must_conflict_p (p->type, type)
677 && (best_p == 0 || best_p->size > p->size
678 || (best_p->size == p->size && best_p->align > p->align)))
680 if (p->align == align && p->size == size)
688 /* Make our best, if any, the one to use. */
691 /* If there are enough aligned bytes left over, make them into a new
692 temp_slot so that the extra bytes don't get wasted. Do this only
693 for BLKmode slots, so that we can be sure of the alignment. */
694 if (GET_MODE (best_p->slot) == BLKmode)
696 int alignment = best_p->align / BITS_PER_UNIT;
697 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
699 if (best_p->size - rounded_size >= alignment)
701 p = (struct temp_slot *) xmalloc (sizeof (struct temp_slot));
702 p->in_use = p->addr_taken = 0;
703 p->size = best_p->size - rounded_size;
704 p->base_offset = best_p->base_offset + rounded_size;
705 p->full_size = best_p->full_size - rounded_size;
706 p->slot = gen_rtx_MEM (BLKmode,
707 plus_constant (XEXP (best_p->slot, 0),
709 p->align = best_p->align;
712 p->type = best_p->type;
713 p->next = temp_slots;
716 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
719 best_p->size = rounded_size;
720 best_p->full_size = rounded_size;
727 /* If we still didn't find one, make a new temporary. */
730 HOST_WIDE_INT frame_offset_old = frame_offset;
732 p = (struct temp_slot *) xmalloc (sizeof (struct temp_slot));
734 /* We are passing an explicit alignment request to assign_stack_local.
735 One side effect of that is assign_stack_local will not round SIZE
736 to ensure the frame offset remains suitably aligned.
738 So for requests which depended on the rounding of SIZE, we go ahead
739 and round it now. We also make sure ALIGNMENT is at least
740 BIGGEST_ALIGNMENT. */
741 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
743 p->slot = assign_stack_local (mode,
745 ? CEIL_ROUND (size, align / BITS_PER_UNIT)
751 /* The following slot size computation is necessary because we don't
752 know the actual size of the temporary slot until assign_stack_local
753 has performed all the frame alignment and size rounding for the
754 requested temporary. Note that extra space added for alignment
755 can be either above or below this stack slot depending on which
756 way the frame grows. We include the extra space if and only if it
757 is above this slot. */
758 #ifdef FRAME_GROWS_DOWNWARD
759 p->size = frame_offset_old - frame_offset;
764 /* Now define the fields used by combine_temp_slots. */
765 #ifdef FRAME_GROWS_DOWNWARD
766 p->base_offset = frame_offset;
767 p->full_size = frame_offset_old - frame_offset;
769 p->base_offset = frame_offset_old;
770 p->full_size = frame_offset - frame_offset_old;
773 p->next = temp_slots;
779 p->rtl_expr = seq_rtl_expr;
784 p->level = target_temp_slot_level;
789 p->level = var_temp_slot_level;
794 p->level = temp_slot_level;
798 /* We may be reusing an old slot, so clear any MEM flags that may have been
800 RTX_UNCHANGING_P (p->slot) = 0;
801 MEM_IN_STRUCT_P (p->slot) = 0;
802 MEM_SCALAR_P (p->slot) = 0;
803 MEM_VOLATILE_P (p->slot) = 0;
805 /* If we know the alias set for the memory that will be used, use
806 it. If there's no TYPE, then we don't know anything about the
807 alias set for the memory. */
809 MEM_ALIAS_SET (p->slot) = get_alias_set (type);
811 MEM_ALIAS_SET (p->slot) = 0;
813 /* If a type is specified, set the relevant flags. */
816 RTX_UNCHANGING_P (p->slot) = TYPE_READONLY (type);
817 MEM_VOLATILE_P (p->slot) = TYPE_VOLATILE (type);
818 MEM_SET_IN_STRUCT_P (p->slot, AGGREGATE_TYPE_P (type));
824 /* Allocate a temporary stack slot and record it for possible later
825 reuse. First three arguments are same as in preceding function. */
828 assign_stack_temp (mode, size, keep)
829 enum machine_mode mode;
833 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
836 /* Assign a temporary of given TYPE.
837 KEEP is as for assign_stack_temp.
838 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
839 it is 0 if a register is OK.
840 DONT_PROMOTE is 1 if we should not promote values in register
844 assign_temp (type, keep, memory_required, dont_promote)
848 int dont_promote ATTRIBUTE_UNUSED;
850 enum machine_mode mode = TYPE_MODE (type);
851 #ifndef PROMOTE_FOR_CALL_ONLY
852 int unsignedp = TREE_UNSIGNED (type);
855 if (mode == BLKmode || memory_required)
857 HOST_WIDE_INT size = int_size_in_bytes (type);
860 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
861 problems with allocating the stack space. */
865 /* Unfortunately, we don't yet know how to allocate variable-sized
866 temporaries. However, sometimes we have a fixed upper limit on
867 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
868 instead. This is the case for Chill variable-sized strings. */
869 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
870 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
871 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
872 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
874 tmp = assign_stack_temp_for_type (mode, size, keep, type);
878 #ifndef PROMOTE_FOR_CALL_ONLY
880 mode = promote_mode (type, mode, &unsignedp, 0);
883 return gen_reg_rtx (mode);
886 /* Combine temporary stack slots which are adjacent on the stack.
888 This allows for better use of already allocated stack space. This is only
889 done for BLKmode slots because we can be sure that we won't have alignment
890 problems in this case. */
893 combine_temp_slots ()
895 struct temp_slot *p, *q;
896 struct temp_slot *prev_p, *prev_q;
899 /* We can't combine slots, because the information about which slot
900 is in which alias set will be lost. */
901 if (flag_strict_aliasing)
904 /* If there are a lot of temp slots, don't do anything unless
905 high levels of optimizaton. */
906 if (! flag_expensive_optimizations)
907 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
908 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
911 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
915 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
916 for (q = p->next, prev_q = p; q; q = prev_q->next)
919 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
921 if (p->base_offset + p->full_size == q->base_offset)
923 /* Q comes after P; combine Q into P. */
925 p->full_size += q->full_size;
928 else if (q->base_offset + q->full_size == p->base_offset)
930 /* P comes after Q; combine P into Q. */
932 q->full_size += p->full_size;
937 /* Either delete Q or advance past it. */
940 prev_q->next = q->next;
946 /* Either delete P or advance past it. */
950 prev_p->next = p->next;
952 temp_slots = p->next;
959 /* Find the temp slot corresponding to the object at address X. */
961 static struct temp_slot *
962 find_temp_slot_from_address (x)
968 for (p = temp_slots; p; p = p->next)
973 else if (XEXP (p->slot, 0) == x
975 || (GET_CODE (x) == PLUS
976 && XEXP (x, 0) == virtual_stack_vars_rtx
977 && GET_CODE (XEXP (x, 1)) == CONST_INT
978 && INTVAL (XEXP (x, 1)) >= p->base_offset
979 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
982 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
983 for (next = p->address; next; next = XEXP (next, 1))
984 if (XEXP (next, 0) == x)
988 /* If we have a sum involving a register, see if it points to a temp
990 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == REG
991 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
993 else if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == REG
994 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
1000 /* Indicate that NEW is an alternate way of referring to the temp slot
1001 that previously was known by OLD. */
1004 update_temp_slot_address (old, new)
1007 struct temp_slot *p;
1009 if (rtx_equal_p (old, new))
1012 p = find_temp_slot_from_address (old);
1014 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
1015 is a register, see if one operand of the PLUS is a temporary
1016 location. If so, NEW points into it. Otherwise, if both OLD and
1017 NEW are a PLUS and if there is a register in common between them.
1018 If so, try a recursive call on those values. */
1021 if (GET_CODE (old) != PLUS)
1024 if (GET_CODE (new) == REG)
1026 update_temp_slot_address (XEXP (old, 0), new);
1027 update_temp_slot_address (XEXP (old, 1), new);
1030 else if (GET_CODE (new) != PLUS)
1033 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
1034 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
1035 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
1036 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
1037 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
1038 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
1039 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
1040 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
1045 /* Otherwise add an alias for the temp's address. */
1046 else if (p->address == 0)
1050 if (GET_CODE (p->address) != EXPR_LIST)
1051 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1053 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1057 /* If X could be a reference to a temporary slot, mark the fact that its
1058 address was taken. */
1061 mark_temp_addr_taken (x)
1064 struct temp_slot *p;
1069 /* If X is not in memory or is at a constant address, it cannot be in
1070 a temporary slot. */
1071 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1074 p = find_temp_slot_from_address (XEXP (x, 0));
1079 /* If X could be a reference to a temporary slot, mark that slot as
1080 belonging to the to one level higher than the current level. If X
1081 matched one of our slots, just mark that one. Otherwise, we can't
1082 easily predict which it is, so upgrade all of them. Kept slots
1083 need not be touched.
1085 This is called when an ({...}) construct occurs and a statement
1086 returns a value in memory. */
1089 preserve_temp_slots (x)
1092 struct temp_slot *p = 0;
1094 /* If there is no result, we still might have some objects whose address
1095 were taken, so we need to make sure they stay around. */
1098 for (p = temp_slots; p; p = p->next)
1099 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1105 /* If X is a register that is being used as a pointer, see if we have
1106 a temporary slot we know it points to. To be consistent with
1107 the code below, we really should preserve all non-kept slots
1108 if we can't find a match, but that seems to be much too costly. */
1109 if (GET_CODE (x) == REG && REG_POINTER (x))
1110 p = find_temp_slot_from_address (x);
1112 /* If X is not in memory or is at a constant address, it cannot be in
1113 a temporary slot, but it can contain something whose address was
1115 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1117 for (p = temp_slots; p; p = p->next)
1118 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1124 /* First see if we can find a match. */
1126 p = find_temp_slot_from_address (XEXP (x, 0));
1130 /* Move everything at our level whose address was taken to our new
1131 level in case we used its address. */
1132 struct temp_slot *q;
1134 if (p->level == temp_slot_level)
1136 for (q = temp_slots; q; q = q->next)
1137 if (q != p && q->addr_taken && q->level == p->level)
1146 /* Otherwise, preserve all non-kept slots at this level. */
1147 for (p = temp_slots; p; p = p->next)
1148 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1152 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1153 with that RTL_EXPR, promote it into a temporary slot at the present
1154 level so it will not be freed when we free slots made in the
1158 preserve_rtl_expr_result (x)
1161 struct temp_slot *p;
1163 /* If X is not in memory or is at a constant address, it cannot be in
1164 a temporary slot. */
1165 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1168 /* If we can find a match, move it to our level unless it is already at
1170 p = find_temp_slot_from_address (XEXP (x, 0));
1173 p->level = MIN (p->level, temp_slot_level);
1180 /* Free all temporaries used so far. This is normally called at the end
1181 of generating code for a statement. Don't free any temporaries
1182 currently in use for an RTL_EXPR that hasn't yet been emitted.
1183 We could eventually do better than this since it can be reused while
1184 generating the same RTL_EXPR, but this is complex and probably not
1190 struct temp_slot *p;
1192 for (p = temp_slots; p; p = p->next)
1193 if (p->in_use && p->level == temp_slot_level && ! p->keep
1194 && p->rtl_expr == 0)
1197 combine_temp_slots ();
1200 /* Free all temporary slots used in T, an RTL_EXPR node. */
1203 free_temps_for_rtl_expr (t)
1206 struct temp_slot *p;
1208 for (p = temp_slots; p; p = p->next)
1209 if (p->rtl_expr == t)
1211 /* If this slot is below the current TEMP_SLOT_LEVEL, then it
1212 needs to be preserved. This can happen if a temporary in
1213 the RTL_EXPR was addressed; preserve_temp_slots will move
1214 the temporary into a higher level. */
1215 if (temp_slot_level <= p->level)
1218 p->rtl_expr = NULL_TREE;
1221 combine_temp_slots ();
1224 /* Mark all temporaries ever allocated in this function as not suitable
1225 for reuse until the current level is exited. */
1228 mark_all_temps_used ()
1230 struct temp_slot *p;
1232 for (p = temp_slots; p; p = p->next)
1234 p->in_use = p->keep = 1;
1235 p->level = MIN (p->level, temp_slot_level);
1239 /* Push deeper into the nesting level for stack temporaries. */
1247 /* Likewise, but save the new level as the place to allocate variables
1252 push_temp_slots_for_block ()
1256 var_temp_slot_level = temp_slot_level;
1259 /* Likewise, but save the new level as the place to allocate temporaries
1260 for TARGET_EXPRs. */
1263 push_temp_slots_for_target ()
1267 target_temp_slot_level = temp_slot_level;
1270 /* Set and get the value of target_temp_slot_level. The only
1271 permitted use of these functions is to save and restore this value. */
1274 get_target_temp_slot_level ()
1276 return target_temp_slot_level;
1280 set_target_temp_slot_level (level)
1283 target_temp_slot_level = level;
1287 /* Pop a temporary nesting level. All slots in use in the current level
1293 struct temp_slot *p;
1295 for (p = temp_slots; p; p = p->next)
1296 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1299 combine_temp_slots ();
1304 /* Initialize temporary slots. */
1309 /* We have not allocated any temporaries yet. */
1311 temp_slot_level = 0;
1312 var_temp_slot_level = 0;
1313 target_temp_slot_level = 0;
1316 /* Retroactively move an auto variable from a register to a stack slot.
1317 This is done when an address-reference to the variable is seen. */
1320 put_var_into_stack (decl)
1324 enum machine_mode promoted_mode, decl_mode;
1325 struct function *function = 0;
1327 int can_use_addressof;
1328 int volatilep = TREE_CODE (decl) != SAVE_EXPR && TREE_THIS_VOLATILE (decl);
1329 int usedp = (TREE_USED (decl)
1330 || (TREE_CODE (decl) != SAVE_EXPR && DECL_INITIAL (decl) != 0));
1332 context = decl_function_context (decl);
1334 /* Get the current rtl used for this object and its original mode. */
1335 reg = (TREE_CODE (decl) == SAVE_EXPR
1336 ? SAVE_EXPR_RTL (decl)
1337 : DECL_RTL_IF_SET (decl));
1339 /* No need to do anything if decl has no rtx yet
1340 since in that case caller is setting TREE_ADDRESSABLE
1341 and a stack slot will be assigned when the rtl is made. */
1345 /* Get the declared mode for this object. */
1346 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1347 : DECL_MODE (decl));
1348 /* Get the mode it's actually stored in. */
1349 promoted_mode = GET_MODE (reg);
1351 /* If this variable comes from an outer function,
1352 find that function's saved context. */
1353 if (context != current_function_decl && context != inline_function_decl)
1354 for (function = outer_function_chain; function; function = function->next)
1355 if (function->decl == context)
1358 /* If this is a variable-size object with a pseudo to address it,
1359 put that pseudo into the stack, if the var is nonlocal. */
1360 if (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl)
1361 && GET_CODE (reg) == MEM
1362 && GET_CODE (XEXP (reg, 0)) == REG
1363 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1365 reg = XEXP (reg, 0);
1366 decl_mode = promoted_mode = GET_MODE (reg);
1372 /* FIXME make it work for promoted modes too */
1373 && decl_mode == promoted_mode
1374 #ifdef NON_SAVING_SETJMP
1375 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1379 /* If we can't use ADDRESSOF, make sure we see through one we already
1381 if (! can_use_addressof && GET_CODE (reg) == MEM
1382 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1383 reg = XEXP (XEXP (reg, 0), 0);
1385 /* Now we should have a value that resides in one or more pseudo regs. */
1387 if (GET_CODE (reg) == REG)
1389 /* If this variable lives in the current function and we don't need
1390 to put things in the stack for the sake of setjmp, try to keep it
1391 in a register until we know we actually need the address. */
1392 if (can_use_addressof)
1393 gen_mem_addressof (reg, decl);
1395 put_reg_into_stack (function, reg, TREE_TYPE (decl), promoted_mode,
1396 decl_mode, volatilep, 0, usedp, 0);
1398 else if (GET_CODE (reg) == CONCAT)
1400 /* A CONCAT contains two pseudos; put them both in the stack.
1401 We do it so they end up consecutive.
1402 We fixup references to the parts only after we fixup references
1403 to the whole CONCAT, lest we do double fixups for the latter
1405 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1406 tree part_type = type_for_mode (part_mode, 0);
1407 rtx lopart = XEXP (reg, 0);
1408 rtx hipart = XEXP (reg, 1);
1409 #ifdef FRAME_GROWS_DOWNWARD
1410 /* Since part 0 should have a lower address, do it second. */
1411 put_reg_into_stack (function, hipart, part_type, part_mode,
1412 part_mode, volatilep, 0, 0, 0);
1413 put_reg_into_stack (function, lopart, part_type, part_mode,
1414 part_mode, volatilep, 0, 0, 0);
1416 put_reg_into_stack (function, lopart, part_type, part_mode,
1417 part_mode, volatilep, 0, 0, 0);
1418 put_reg_into_stack (function, hipart, part_type, part_mode,
1419 part_mode, volatilep, 0, 0, 0);
1422 /* Change the CONCAT into a combined MEM for both parts. */
1423 PUT_CODE (reg, MEM);
1424 set_mem_attributes (reg, decl, 1);
1426 /* The two parts are in memory order already.
1427 Use the lower parts address as ours. */
1428 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1429 /* Prevent sharing of rtl that might lose. */
1430 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1431 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1434 schedule_fixup_var_refs (function, reg, TREE_TYPE (decl),
1436 schedule_fixup_var_refs (function, lopart, part_type, part_mode, 0);
1437 schedule_fixup_var_refs (function, hipart, part_type, part_mode, 0);
1443 if (current_function_check_memory_usage)
1444 emit_library_call (chkr_set_right_libfunc, LCT_CONST_MAKE_BLOCK, VOIDmode,
1445 3, XEXP (reg, 0), Pmode,
1446 GEN_INT (GET_MODE_SIZE (GET_MODE (reg))),
1447 TYPE_MODE (sizetype),
1448 GEN_INT (MEMORY_USE_RW),
1449 TYPE_MODE (integer_type_node));
1452 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1453 into the stack frame of FUNCTION (0 means the current function).
1454 DECL_MODE is the machine mode of the user-level data type.
1455 PROMOTED_MODE is the machine mode of the register.
1456 VOLATILE_P is nonzero if this is for a "volatile" decl.
1457 USED_P is nonzero if this reg might have already been used in an insn. */
1460 put_reg_into_stack (function, reg, type, promoted_mode, decl_mode, volatile_p,
1461 original_regno, used_p, ht)
1462 struct function *function;
1465 enum machine_mode promoted_mode, decl_mode;
1467 unsigned int original_regno;
1469 struct hash_table *ht;
1471 struct function *func = function ? function : cfun;
1473 unsigned int regno = original_regno;
1476 regno = REGNO (reg);
1478 if (regno < func->x_max_parm_reg)
1479 new = func->x_parm_reg_stack_loc[regno];
1482 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode), 0, func);
1484 PUT_CODE (reg, MEM);
1485 PUT_MODE (reg, decl_mode);
1486 XEXP (reg, 0) = XEXP (new, 0);
1487 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1488 MEM_VOLATILE_P (reg) = volatile_p;
1490 /* If this is a memory ref that contains aggregate components,
1491 mark it as such for cse and loop optimize. If we are reusing a
1492 previously generated stack slot, then we need to copy the bit in
1493 case it was set for other reasons. For instance, it is set for
1494 __builtin_va_alist. */
1497 MEM_SET_IN_STRUCT_P (reg,
1498 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1499 MEM_ALIAS_SET (reg) = get_alias_set (type);
1502 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht);
1505 /* Make sure that all refs to the variable, previously made
1506 when it was a register, are fixed up to be valid again.
1507 See function above for meaning of arguments. */
1510 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht)
1511 struct function *function;
1514 enum machine_mode promoted_mode;
1515 struct hash_table *ht;
1517 int unsigned_p = type ? TREE_UNSIGNED (type) : 0;
1521 struct var_refs_queue *temp;
1524 = (struct var_refs_queue *) xmalloc (sizeof (struct var_refs_queue));
1525 temp->modified = reg;
1526 temp->promoted_mode = promoted_mode;
1527 temp->unsignedp = unsigned_p;
1528 temp->next = function->fixup_var_refs_queue;
1529 function->fixup_var_refs_queue = temp;
1532 /* Variable is local; fix it up now. */
1533 fixup_var_refs (reg, promoted_mode, unsigned_p, ht);
1537 fixup_var_refs (var, promoted_mode, unsignedp, ht)
1539 enum machine_mode promoted_mode;
1541 struct hash_table *ht;
1544 rtx first_insn = get_insns ();
1545 struct sequence_stack *stack = seq_stack;
1546 tree rtl_exps = rtl_expr_chain;
1548 /* If there's a hash table, it must record all uses of VAR. */
1553 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp);
1557 fixup_var_refs_insns (first_insn, var, promoted_mode, unsignedp,
1560 /* Scan all pending sequences too. */
1561 for (; stack; stack = stack->next)
1563 push_to_full_sequence (stack->first, stack->last);
1564 fixup_var_refs_insns (stack->first, var, promoted_mode, unsignedp,
1566 /* Update remembered end of sequence
1567 in case we added an insn at the end. */
1568 stack->last = get_last_insn ();
1572 /* Scan all waiting RTL_EXPRs too. */
1573 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1575 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1576 if (seq != const0_rtx && seq != 0)
1578 push_to_sequence (seq);
1579 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0);
1585 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1586 some part of an insn. Return a struct fixup_replacement whose OLD
1587 value is equal to X. Allocate a new structure if no such entry exists. */
1589 static struct fixup_replacement *
1590 find_fixup_replacement (replacements, x)
1591 struct fixup_replacement **replacements;
1594 struct fixup_replacement *p;
1596 /* See if we have already replaced this. */
1597 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1602 p = (struct fixup_replacement *) xmalloc (sizeof (struct fixup_replacement));
1605 p->next = *replacements;
1612 /* Scan the insn-chain starting with INSN for refs to VAR
1613 and fix them up. TOPLEVEL is nonzero if this chain is the
1614 main chain of insns for the current function. */
1617 fixup_var_refs_insns (insn, var, promoted_mode, unsignedp, toplevel)
1620 enum machine_mode promoted_mode;
1626 /* fixup_var_refs_insn might modify insn, so save its next
1628 rtx next = NEXT_INSN (insn);
1630 /* CALL_PLACEHOLDERs are special; we have to switch into each of
1631 the three sequences they (potentially) contain, and process
1632 them recursively. The CALL_INSN itself is not interesting. */
1634 if (GET_CODE (insn) == CALL_INSN
1635 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
1639 /* Look at the Normal call, sibling call and tail recursion
1640 sequences attached to the CALL_PLACEHOLDER. */
1641 for (i = 0; i < 3; i++)
1643 rtx seq = XEXP (PATTERN (insn), i);
1646 push_to_sequence (seq);
1647 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0);
1648 XEXP (PATTERN (insn), i) = get_insns ();
1654 else if (INSN_P (insn))
1655 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel);
1661 /* Look up the insns which reference VAR in HT and fix them up. Other
1662 arguments are the same as fixup_var_refs_insns.
1664 N.B. No need for special processing of CALL_PLACEHOLDERs here,
1665 because the hash table will point straight to the interesting insn
1666 (inside the CALL_PLACEHOLDER). */
1668 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp)
1669 struct hash_table *ht;
1671 enum machine_mode promoted_mode;
1674 struct insns_for_mem_entry *ime = (struct insns_for_mem_entry *)
1675 hash_lookup (ht, var, /*create=*/0, /*copy=*/0);
1676 rtx insn_list = ime->insns;
1680 rtx insn = XEXP (insn_list, 0);
1683 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, 0);
1685 insn_list = XEXP (insn_list, 1);
1690 /* Per-insn processing by fixup_var_refs_insns(_with_hash). INSN is
1691 the insn under examination, VAR is the variable to fix up
1692 references to, PROMOTED_MODE and UNSIGNEDP describe VAR, and
1693 TOPLEVEL is nonzero if this is the main insn chain for this
1696 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel)
1699 enum machine_mode promoted_mode;
1704 rtx set, prev, prev_set;
1707 /* Remember the notes in case we delete the insn. */
1708 note = REG_NOTES (insn);
1710 /* If this is a CLOBBER of VAR, delete it.
1712 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1713 and REG_RETVAL notes too. */
1714 if (GET_CODE (PATTERN (insn)) == CLOBBER
1715 && (XEXP (PATTERN (insn), 0) == var
1716 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1717 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1718 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1720 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1721 /* The REG_LIBCALL note will go away since we are going to
1722 turn INSN into a NOTE, so just delete the
1723 corresponding REG_RETVAL note. */
1724 remove_note (XEXP (note, 0),
1725 find_reg_note (XEXP (note, 0), REG_RETVAL,
1728 /* In unoptimized compilation, we shouldn't call delete_insn
1729 except in jump.c doing warnings. */
1730 PUT_CODE (insn, NOTE);
1731 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1732 NOTE_SOURCE_FILE (insn) = 0;
1735 /* The insn to load VAR from a home in the arglist
1736 is now a no-op. When we see it, just delete it.
1737 Similarly if this is storing VAR from a register from which
1738 it was loaded in the previous insn. This will occur
1739 when an ADDRESSOF was made for an arglist slot. */
1741 && (set = single_set (insn)) != 0
1742 && SET_DEST (set) == var
1743 /* If this represents the result of an insn group,
1744 don't delete the insn. */
1745 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1746 && (rtx_equal_p (SET_SRC (set), var)
1747 || (GET_CODE (SET_SRC (set)) == REG
1748 && (prev = prev_nonnote_insn (insn)) != 0
1749 && (prev_set = single_set (prev)) != 0
1750 && SET_DEST (prev_set) == SET_SRC (set)
1751 && rtx_equal_p (SET_SRC (prev_set), var))))
1753 /* In unoptimized compilation, we shouldn't call delete_insn
1754 except in jump.c doing warnings. */
1755 PUT_CODE (insn, NOTE);
1756 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1757 NOTE_SOURCE_FILE (insn) = 0;
1761 struct fixup_replacement *replacements = 0;
1762 rtx next_insn = NEXT_INSN (insn);
1764 if (SMALL_REGISTER_CLASSES)
1766 /* If the insn that copies the results of a CALL_INSN
1767 into a pseudo now references VAR, we have to use an
1768 intermediate pseudo since we want the life of the
1769 return value register to be only a single insn.
1771 If we don't use an intermediate pseudo, such things as
1772 address computations to make the address of VAR valid
1773 if it is not can be placed between the CALL_INSN and INSN.
1775 To make sure this doesn't happen, we record the destination
1776 of the CALL_INSN and see if the next insn uses both that
1779 if (call_dest != 0 && GET_CODE (insn) == INSN
1780 && reg_mentioned_p (var, PATTERN (insn))
1781 && reg_mentioned_p (call_dest, PATTERN (insn)))
1783 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1785 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1787 PATTERN (insn) = replace_rtx (PATTERN (insn),
1791 if (GET_CODE (insn) == CALL_INSN
1792 && GET_CODE (PATTERN (insn)) == SET)
1793 call_dest = SET_DEST (PATTERN (insn));
1794 else if (GET_CODE (insn) == CALL_INSN
1795 && GET_CODE (PATTERN (insn)) == PARALLEL
1796 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1797 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1802 /* See if we have to do anything to INSN now that VAR is in
1803 memory. If it needs to be loaded into a pseudo, use a single
1804 pseudo for the entire insn in case there is a MATCH_DUP
1805 between two operands. We pass a pointer to the head of
1806 a list of struct fixup_replacements. If fixup_var_refs_1
1807 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1808 it will record them in this list.
1810 If it allocated a pseudo for any replacement, we copy into
1813 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1816 /* If this is last_parm_insn, and any instructions were output
1817 after it to fix it up, then we must set last_parm_insn to
1818 the last such instruction emitted. */
1819 if (insn == last_parm_insn)
1820 last_parm_insn = PREV_INSN (next_insn);
1822 while (replacements)
1824 struct fixup_replacement *next;
1826 if (GET_CODE (replacements->new) == REG)
1831 /* OLD might be a (subreg (mem)). */
1832 if (GET_CODE (replacements->old) == SUBREG)
1834 = fixup_memory_subreg (replacements->old, insn, 0);
1837 = fixup_stack_1 (replacements->old, insn);
1839 insert_before = insn;
1841 /* If we are changing the mode, do a conversion.
1842 This might be wasteful, but combine.c will
1843 eliminate much of the waste. */
1845 if (GET_MODE (replacements->new)
1846 != GET_MODE (replacements->old))
1849 convert_move (replacements->new,
1850 replacements->old, unsignedp);
1851 seq = gen_sequence ();
1855 seq = gen_move_insn (replacements->new,
1858 emit_insn_before (seq, insert_before);
1861 next = replacements->next;
1862 free (replacements);
1863 replacements = next;
1867 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1868 But don't touch other insns referred to by reg-notes;
1869 we will get them elsewhere. */
1872 if (GET_CODE (note) != INSN_LIST)
1874 = walk_fixup_memory_subreg (XEXP (note, 0), insn, 1);
1875 note = XEXP (note, 1);
1879 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1880 See if the rtx expression at *LOC in INSN needs to be changed.
1882 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1883 contain a list of original rtx's and replacements. If we find that we need
1884 to modify this insn by replacing a memory reference with a pseudo or by
1885 making a new MEM to implement a SUBREG, we consult that list to see if
1886 we have already chosen a replacement. If none has already been allocated,
1887 we allocate it and update the list. fixup_var_refs_insn will copy VAR
1888 or the SUBREG, as appropriate, to the pseudo. */
1891 fixup_var_refs_1 (var, promoted_mode, loc, insn, replacements)
1893 enum machine_mode promoted_mode;
1896 struct fixup_replacement **replacements;
1899 register rtx x = *loc;
1900 RTX_CODE code = GET_CODE (x);
1901 register const char *fmt;
1902 register rtx tem, tem1;
1903 struct fixup_replacement *replacement;
1908 if (XEXP (x, 0) == var)
1910 /* Prevent sharing of rtl that might lose. */
1911 rtx sub = copy_rtx (XEXP (var, 0));
1913 if (! validate_change (insn, loc, sub, 0))
1915 rtx y = gen_reg_rtx (GET_MODE (sub));
1918 /* We should be able to replace with a register or all is lost.
1919 Note that we can't use validate_change to verify this, since
1920 we're not caring for replacing all dups simultaneously. */
1921 if (! validate_replace_rtx (*loc, y, insn))
1924 /* Careful! First try to recognize a direct move of the
1925 value, mimicking how things are done in gen_reload wrt
1926 PLUS. Consider what happens when insn is a conditional
1927 move instruction and addsi3 clobbers flags. */
1930 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1931 seq = gen_sequence ();
1934 if (recog_memoized (new_insn) < 0)
1936 /* That failed. Fall back on force_operand and hope. */
1939 sub = force_operand (sub, y);
1941 emit_insn (gen_move_insn (y, sub));
1942 seq = gen_sequence ();
1947 /* Don't separate setter from user. */
1948 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1949 insn = PREV_INSN (insn);
1952 emit_insn_before (seq, insn);
1960 /* If we already have a replacement, use it. Otherwise,
1961 try to fix up this address in case it is invalid. */
1963 replacement = find_fixup_replacement (replacements, var);
1964 if (replacement->new)
1966 *loc = replacement->new;
1970 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1972 /* Unless we are forcing memory to register or we changed the mode,
1973 we can leave things the way they are if the insn is valid. */
1975 INSN_CODE (insn) = -1;
1976 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1977 && recog_memoized (insn) >= 0)
1980 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1984 /* If X contains VAR, we need to unshare it here so that we update
1985 each occurrence separately. But all identical MEMs in one insn
1986 must be replaced with the same rtx because of the possibility of
1989 if (reg_mentioned_p (var, x))
1991 replacement = find_fixup_replacement (replacements, x);
1992 if (replacement->new == 0)
1993 replacement->new = copy_most_rtx (x, var);
1995 *loc = x = replacement->new;
1996 code = GET_CODE (x);
2012 /* Note that in some cases those types of expressions are altered
2013 by optimize_bit_field, and do not survive to get here. */
2014 if (XEXP (x, 0) == var
2015 || (GET_CODE (XEXP (x, 0)) == SUBREG
2016 && SUBREG_REG (XEXP (x, 0)) == var))
2018 /* Get TEM as a valid MEM in the mode presently in the insn.
2020 We don't worry about the possibility of MATCH_DUP here; it
2021 is highly unlikely and would be tricky to handle. */
2024 if (GET_CODE (tem) == SUBREG)
2026 if (GET_MODE_BITSIZE (GET_MODE (tem))
2027 > GET_MODE_BITSIZE (GET_MODE (var)))
2029 replacement = find_fixup_replacement (replacements, var);
2030 if (replacement->new == 0)
2031 replacement->new = gen_reg_rtx (GET_MODE (var));
2032 SUBREG_REG (tem) = replacement->new;
2034 /* The following code works only if we have a MEM, so we
2035 need to handle the subreg here. We directly substitute
2036 it assuming that a subreg must be OK here. We already
2037 scheduled a replacement to copy the mem into the
2043 tem = fixup_memory_subreg (tem, insn, 0);
2046 tem = fixup_stack_1 (tem, insn);
2048 /* Unless we want to load from memory, get TEM into the proper mode
2049 for an extract from memory. This can only be done if the
2050 extract is at a constant position and length. */
2052 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
2053 && GET_CODE (XEXP (x, 2)) == CONST_INT
2054 && ! mode_dependent_address_p (XEXP (tem, 0))
2055 && ! MEM_VOLATILE_P (tem))
2057 enum machine_mode wanted_mode = VOIDmode;
2058 enum machine_mode is_mode = GET_MODE (tem);
2059 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
2062 if (GET_CODE (x) == ZERO_EXTRACT)
2065 = insn_data[(int) CODE_FOR_extzv].operand[1].mode;
2066 if (wanted_mode == VOIDmode)
2067 wanted_mode = word_mode;
2071 if (GET_CODE (x) == SIGN_EXTRACT)
2073 wanted_mode = insn_data[(int) CODE_FOR_extv].operand[1].mode;
2074 if (wanted_mode == VOIDmode)
2075 wanted_mode = word_mode;
2078 /* If we have a narrower mode, we can do something. */
2079 if (wanted_mode != VOIDmode
2080 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2082 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2083 rtx old_pos = XEXP (x, 2);
2086 /* If the bytes and bits are counted differently, we
2087 must adjust the offset. */
2088 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2089 offset = (GET_MODE_SIZE (is_mode)
2090 - GET_MODE_SIZE (wanted_mode) - offset);
2092 pos %= GET_MODE_BITSIZE (wanted_mode);
2094 newmem = gen_rtx_MEM (wanted_mode,
2095 plus_constant (XEXP (tem, 0), offset));
2096 MEM_COPY_ATTRIBUTES (newmem, tem);
2098 /* Make the change and see if the insn remains valid. */
2099 INSN_CODE (insn) = -1;
2100 XEXP (x, 0) = newmem;
2101 XEXP (x, 2) = GEN_INT (pos);
2103 if (recog_memoized (insn) >= 0)
2106 /* Otherwise, restore old position. XEXP (x, 0) will be
2108 XEXP (x, 2) = old_pos;
2112 /* If we get here, the bitfield extract insn can't accept a memory
2113 reference. Copy the input into a register. */
2115 tem1 = gen_reg_rtx (GET_MODE (tem));
2116 emit_insn_before (gen_move_insn (tem1, tem), insn);
2123 if (SUBREG_REG (x) == var)
2125 /* If this is a special SUBREG made because VAR was promoted
2126 from a wider mode, replace it with VAR and call ourself
2127 recursively, this time saying that the object previously
2128 had its current mode (by virtue of the SUBREG). */
2130 if (SUBREG_PROMOTED_VAR_P (x))
2133 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements);
2137 /* If this SUBREG makes VAR wider, it has become a paradoxical
2138 SUBREG with VAR in memory, but these aren't allowed at this
2139 stage of the compilation. So load VAR into a pseudo and take
2140 a SUBREG of that pseudo. */
2141 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2143 replacement = find_fixup_replacement (replacements, var);
2144 if (replacement->new == 0)
2145 replacement->new = gen_reg_rtx (GET_MODE (var));
2146 SUBREG_REG (x) = replacement->new;
2150 /* See if we have already found a replacement for this SUBREG.
2151 If so, use it. Otherwise, make a MEM and see if the insn
2152 is recognized. If not, or if we should force MEM into a register,
2153 make a pseudo for this SUBREG. */
2154 replacement = find_fixup_replacement (replacements, x);
2155 if (replacement->new)
2157 *loc = replacement->new;
2161 replacement->new = *loc = fixup_memory_subreg (x, insn, 0);
2163 INSN_CODE (insn) = -1;
2164 if (! flag_force_mem && recog_memoized (insn) >= 0)
2167 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2173 /* First do special simplification of bit-field references. */
2174 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2175 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2176 optimize_bit_field (x, insn, 0);
2177 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2178 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2179 optimize_bit_field (x, insn, NULL_PTR);
2181 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2182 into a register and then store it back out. */
2183 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2184 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2185 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2186 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2187 > GET_MODE_SIZE (GET_MODE (var))))
2189 replacement = find_fixup_replacement (replacements, var);
2190 if (replacement->new == 0)
2191 replacement->new = gen_reg_rtx (GET_MODE (var));
2193 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2194 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2197 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2198 insn into a pseudo and store the low part of the pseudo into VAR. */
2199 if (GET_CODE (SET_DEST (x)) == SUBREG
2200 && SUBREG_REG (SET_DEST (x)) == var
2201 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2202 > GET_MODE_SIZE (GET_MODE (var))))
2204 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2205 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2212 rtx dest = SET_DEST (x);
2213 rtx src = SET_SRC (x);
2215 rtx outerdest = dest;
2218 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2219 || GET_CODE (dest) == SIGN_EXTRACT
2220 || GET_CODE (dest) == ZERO_EXTRACT)
2221 dest = XEXP (dest, 0);
2223 if (GET_CODE (src) == SUBREG)
2224 src = SUBREG_REG (src);
2226 /* If VAR does not appear at the top level of the SET
2227 just scan the lower levels of the tree. */
2229 if (src != var && dest != var)
2232 /* We will need to rerecognize this insn. */
2233 INSN_CODE (insn) = -1;
2236 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var)
2238 /* Since this case will return, ensure we fixup all the
2240 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2241 insn, replacements);
2242 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2243 insn, replacements);
2244 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2245 insn, replacements);
2247 tem = XEXP (outerdest, 0);
2249 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2250 that may appear inside a ZERO_EXTRACT.
2251 This was legitimate when the MEM was a REG. */
2252 if (GET_CODE (tem) == SUBREG
2253 && SUBREG_REG (tem) == var)
2254 tem = fixup_memory_subreg (tem, insn, 0);
2256 tem = fixup_stack_1 (tem, insn);
2258 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2259 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2260 && ! mode_dependent_address_p (XEXP (tem, 0))
2261 && ! MEM_VOLATILE_P (tem))
2263 enum machine_mode wanted_mode;
2264 enum machine_mode is_mode = GET_MODE (tem);
2265 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2267 wanted_mode = insn_data[(int) CODE_FOR_insv].operand[0].mode;
2268 if (wanted_mode == VOIDmode)
2269 wanted_mode = word_mode;
2271 /* If we have a narrower mode, we can do something. */
2272 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2274 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2275 rtx old_pos = XEXP (outerdest, 2);
2278 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2279 offset = (GET_MODE_SIZE (is_mode)
2280 - GET_MODE_SIZE (wanted_mode) - offset);
2282 pos %= GET_MODE_BITSIZE (wanted_mode);
2284 newmem = gen_rtx_MEM (wanted_mode,
2285 plus_constant (XEXP (tem, 0),
2287 MEM_COPY_ATTRIBUTES (newmem, tem);
2289 /* Make the change and see if the insn remains valid. */
2290 INSN_CODE (insn) = -1;
2291 XEXP (outerdest, 0) = newmem;
2292 XEXP (outerdest, 2) = GEN_INT (pos);
2294 if (recog_memoized (insn) >= 0)
2297 /* Otherwise, restore old position. XEXP (x, 0) will be
2299 XEXP (outerdest, 2) = old_pos;
2303 /* If we get here, the bit-field store doesn't allow memory
2304 or isn't located at a constant position. Load the value into
2305 a register, do the store, and put it back into memory. */
2307 tem1 = gen_reg_rtx (GET_MODE (tem));
2308 emit_insn_before (gen_move_insn (tem1, tem), insn);
2309 emit_insn_after (gen_move_insn (tem, tem1), insn);
2310 XEXP (outerdest, 0) = tem1;
2315 /* STRICT_LOW_PART is a no-op on memory references
2316 and it can cause combinations to be unrecognizable,
2319 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2320 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2322 /* A valid insn to copy VAR into or out of a register
2323 must be left alone, to avoid an infinite loop here.
2324 If the reference to VAR is by a subreg, fix that up,
2325 since SUBREG is not valid for a memref.
2326 Also fix up the address of the stack slot.
2328 Note that we must not try to recognize the insn until
2329 after we know that we have valid addresses and no
2330 (subreg (mem ...) ...) constructs, since these interfere
2331 with determining the validity of the insn. */
2333 if ((SET_SRC (x) == var
2334 || (GET_CODE (SET_SRC (x)) == SUBREG
2335 && SUBREG_REG (SET_SRC (x)) == var))
2336 && (GET_CODE (SET_DEST (x)) == REG
2337 || (GET_CODE (SET_DEST (x)) == SUBREG
2338 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2339 && GET_MODE (var) == promoted_mode
2340 && x == single_set (insn))
2344 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2345 if (replacement->new)
2346 SET_SRC (x) = replacement->new;
2347 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2348 SET_SRC (x) = replacement->new
2349 = fixup_memory_subreg (SET_SRC (x), insn, 0);
2351 SET_SRC (x) = replacement->new
2352 = fixup_stack_1 (SET_SRC (x), insn);
2354 if (recog_memoized (insn) >= 0)
2357 /* INSN is not valid, but we know that we want to
2358 copy SET_SRC (x) to SET_DEST (x) in some way. So
2359 we generate the move and see whether it requires more
2360 than one insn. If it does, we emit those insns and
2361 delete INSN. Otherwise, we an just replace the pattern
2362 of INSN; we have already verified above that INSN has
2363 no other function that to do X. */
2365 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2366 if (GET_CODE (pat) == SEQUENCE)
2368 last = emit_insn_before (pat, insn);
2370 /* INSN might have REG_RETVAL or other important notes, so
2371 we need to store the pattern of the last insn in the
2372 sequence into INSN similarly to the normal case. LAST
2373 should not have REG_NOTES, but we allow them if INSN has
2375 if (REG_NOTES (last) && REG_NOTES (insn))
2377 if (REG_NOTES (last))
2378 REG_NOTES (insn) = REG_NOTES (last);
2379 PATTERN (insn) = PATTERN (last);
2381 PUT_CODE (last, NOTE);
2382 NOTE_LINE_NUMBER (last) = NOTE_INSN_DELETED;
2383 NOTE_SOURCE_FILE (last) = 0;
2386 PATTERN (insn) = pat;
2391 if ((SET_DEST (x) == var
2392 || (GET_CODE (SET_DEST (x)) == SUBREG
2393 && SUBREG_REG (SET_DEST (x)) == var))
2394 && (GET_CODE (SET_SRC (x)) == REG
2395 || (GET_CODE (SET_SRC (x)) == SUBREG
2396 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2397 && GET_MODE (var) == promoted_mode
2398 && x == single_set (insn))
2402 if (GET_CODE (SET_DEST (x)) == SUBREG)
2403 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn, 0);
2405 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2407 if (recog_memoized (insn) >= 0)
2410 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2411 if (GET_CODE (pat) == SEQUENCE)
2413 last = emit_insn_before (pat, insn);
2415 /* INSN might have REG_RETVAL or other important notes, so
2416 we need to store the pattern of the last insn in the
2417 sequence into INSN similarly to the normal case. LAST
2418 should not have REG_NOTES, but we allow them if INSN has
2420 if (REG_NOTES (last) && REG_NOTES (insn))
2422 if (REG_NOTES (last))
2423 REG_NOTES (insn) = REG_NOTES (last);
2424 PATTERN (insn) = PATTERN (last);
2426 PUT_CODE (last, NOTE);
2427 NOTE_LINE_NUMBER (last) = NOTE_INSN_DELETED;
2428 NOTE_SOURCE_FILE (last) = 0;
2431 PATTERN (insn) = pat;
2436 /* Otherwise, storing into VAR must be handled specially
2437 by storing into a temporary and copying that into VAR
2438 with a new insn after this one. Note that this case
2439 will be used when storing into a promoted scalar since
2440 the insn will now have different modes on the input
2441 and output and hence will be invalid (except for the case
2442 of setting it to a constant, which does not need any
2443 change if it is valid). We generate extra code in that case,
2444 but combine.c will eliminate it. */
2449 rtx fixeddest = SET_DEST (x);
2451 /* STRICT_LOW_PART can be discarded, around a MEM. */
2452 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2453 fixeddest = XEXP (fixeddest, 0);
2454 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2455 if (GET_CODE (fixeddest) == SUBREG)
2457 fixeddest = fixup_memory_subreg (fixeddest, insn, 0);
2458 promoted_mode = GET_MODE (fixeddest);
2461 fixeddest = fixup_stack_1 (fixeddest, insn);
2463 temp = gen_reg_rtx (promoted_mode);
2465 emit_insn_after (gen_move_insn (fixeddest,
2466 gen_lowpart (GET_MODE (fixeddest),
2470 SET_DEST (x) = temp;
2478 /* Nothing special about this RTX; fix its operands. */
2480 fmt = GET_RTX_FORMAT (code);
2481 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2484 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements);
2485 else if (fmt[i] == 'E')
2488 for (j = 0; j < XVECLEN (x, i); j++)
2489 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2490 insn, replacements);
2495 /* Given X, an rtx of the form (SUBREG:m1 (MEM:m2 addr)),
2496 return an rtx (MEM:m1 newaddr) which is equivalent.
2497 If any insns must be emitted to compute NEWADDR, put them before INSN.
2499 UNCRITICAL nonzero means accept paradoxical subregs.
2500 This is used for subregs found inside REG_NOTES. */
2503 fixup_memory_subreg (x, insn, uncritical)
2508 int offset = SUBREG_BYTE (x);
2509 rtx addr = XEXP (SUBREG_REG (x), 0);
2510 enum machine_mode mode = GET_MODE (x);
2513 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2514 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))
2518 addr = plus_constant (addr, offset);
2519 if (!flag_force_addr && memory_address_p (mode, addr))
2520 /* Shortcut if no insns need be emitted. */
2521 return change_address (SUBREG_REG (x), mode, addr);
2523 result = change_address (SUBREG_REG (x), mode, addr);
2524 emit_insn_before (gen_sequence (), insn);
2529 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2530 Replace subexpressions of X in place.
2531 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2532 Otherwise return X, with its contents possibly altered.
2534 If any insns must be emitted to compute NEWADDR, put them before INSN.
2536 UNCRITICAL is as in fixup_memory_subreg. */
2539 walk_fixup_memory_subreg (x, insn, uncritical)
2544 register enum rtx_code code;
2545 register const char *fmt;
2551 code = GET_CODE (x);
2553 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2554 return fixup_memory_subreg (x, insn, uncritical);
2556 /* Nothing special about this RTX; fix its operands. */
2558 fmt = GET_RTX_FORMAT (code);
2559 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2562 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn, uncritical);
2563 else if (fmt[i] == 'E')
2566 for (j = 0; j < XVECLEN (x, i); j++)
2568 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn, uncritical);
2574 /* For each memory ref within X, if it refers to a stack slot
2575 with an out of range displacement, put the address in a temp register
2576 (emitting new insns before INSN to load these registers)
2577 and alter the memory ref to use that register.
2578 Replace each such MEM rtx with a copy, to avoid clobberage. */
2581 fixup_stack_1 (x, insn)
2586 register RTX_CODE code = GET_CODE (x);
2587 register const char *fmt;
2591 register rtx ad = XEXP (x, 0);
2592 /* If we have address of a stack slot but it's not valid
2593 (displacement is too large), compute the sum in a register. */
2594 if (GET_CODE (ad) == PLUS
2595 && GET_CODE (XEXP (ad, 0)) == REG
2596 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2597 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2598 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2599 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2600 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2602 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2603 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2604 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2605 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2608 if (memory_address_p (GET_MODE (x), ad))
2612 temp = copy_to_reg (ad);
2613 seq = gen_sequence ();
2615 emit_insn_before (seq, insn);
2616 return change_address (x, VOIDmode, temp);
2621 fmt = GET_RTX_FORMAT (code);
2622 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2625 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2626 else if (fmt[i] == 'E')
2629 for (j = 0; j < XVECLEN (x, i); j++)
2630 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2636 /* Optimization: a bit-field instruction whose field
2637 happens to be a byte or halfword in memory
2638 can be changed to a move instruction.
2640 We call here when INSN is an insn to examine or store into a bit-field.
2641 BODY is the SET-rtx to be altered.
2643 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2644 (Currently this is called only from function.c, and EQUIV_MEM
2648 optimize_bit_field (body, insn, equiv_mem)
2653 register rtx bitfield;
2656 enum machine_mode mode;
2658 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2659 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2660 bitfield = SET_DEST (body), destflag = 1;
2662 bitfield = SET_SRC (body), destflag = 0;
2664 /* First check that the field being stored has constant size and position
2665 and is in fact a byte or halfword suitably aligned. */
2667 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2668 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2669 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2671 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2673 register rtx memref = 0;
2675 /* Now check that the containing word is memory, not a register,
2676 and that it is safe to change the machine mode. */
2678 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2679 memref = XEXP (bitfield, 0);
2680 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2682 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2683 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2684 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2685 memref = SUBREG_REG (XEXP (bitfield, 0));
2686 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2688 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2689 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2692 && ! mode_dependent_address_p (XEXP (memref, 0))
2693 && ! MEM_VOLATILE_P (memref))
2695 /* Now adjust the address, first for any subreg'ing
2696 that we are now getting rid of,
2697 and then for which byte of the word is wanted. */
2699 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2702 /* Adjust OFFSET to count bits from low-address byte. */
2703 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2704 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2705 - offset - INTVAL (XEXP (bitfield, 1)));
2707 /* Adjust OFFSET to count bytes from low-address byte. */
2708 offset /= BITS_PER_UNIT;
2709 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2711 offset += (SUBREG_BYTE (XEXP (bitfield, 0))
2712 / UNITS_PER_WORD) * UNITS_PER_WORD;
2713 if (BYTES_BIG_ENDIAN)
2714 offset -= (MIN (UNITS_PER_WORD,
2715 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2716 - MIN (UNITS_PER_WORD,
2717 GET_MODE_SIZE (GET_MODE (memref))));
2721 memref = change_address (memref, mode,
2722 plus_constant (XEXP (memref, 0), offset));
2723 insns = get_insns ();
2725 emit_insns_before (insns, insn);
2727 /* Store this memory reference where
2728 we found the bit field reference. */
2732 validate_change (insn, &SET_DEST (body), memref, 1);
2733 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2735 rtx src = SET_SRC (body);
2736 while (GET_CODE (src) == SUBREG
2737 && SUBREG_BYTE (src) == 0)
2738 src = SUBREG_REG (src);
2739 if (GET_MODE (src) != GET_MODE (memref))
2740 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2741 validate_change (insn, &SET_SRC (body), src, 1);
2743 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2744 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2745 /* This shouldn't happen because anything that didn't have
2746 one of these modes should have got converted explicitly
2747 and then referenced through a subreg.
2748 This is so because the original bit-field was
2749 handled by agg_mode and so its tree structure had
2750 the same mode that memref now has. */
2755 rtx dest = SET_DEST (body);
2757 while (GET_CODE (dest) == SUBREG
2758 && SUBREG_BYTE (dest) == 0
2759 && (GET_MODE_CLASS (GET_MODE (dest))
2760 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2761 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2763 dest = SUBREG_REG (dest);
2765 validate_change (insn, &SET_DEST (body), dest, 1);
2767 if (GET_MODE (dest) == GET_MODE (memref))
2768 validate_change (insn, &SET_SRC (body), memref, 1);
2771 /* Convert the mem ref to the destination mode. */
2772 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2775 convert_move (newreg, memref,
2776 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2780 validate_change (insn, &SET_SRC (body), newreg, 1);
2784 /* See if we can convert this extraction or insertion into
2785 a simple move insn. We might not be able to do so if this
2786 was, for example, part of a PARALLEL.
2788 If we succeed, write out any needed conversions. If we fail,
2789 it is hard to guess why we failed, so don't do anything
2790 special; just let the optimization be suppressed. */
2792 if (apply_change_group () && seq)
2793 emit_insns_before (seq, insn);
2798 /* These routines are responsible for converting virtual register references
2799 to the actual hard register references once RTL generation is complete.
2801 The following four variables are used for communication between the
2802 routines. They contain the offsets of the virtual registers from their
2803 respective hard registers. */
2805 static int in_arg_offset;
2806 static int var_offset;
2807 static int dynamic_offset;
2808 static int out_arg_offset;
2809 static int cfa_offset;
2811 /* In most machines, the stack pointer register is equivalent to the bottom
2814 #ifndef STACK_POINTER_OFFSET
2815 #define STACK_POINTER_OFFSET 0
2818 /* If not defined, pick an appropriate default for the offset of dynamically
2819 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2820 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2822 #ifndef STACK_DYNAMIC_OFFSET
2824 /* The bottom of the stack points to the actual arguments. If
2825 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2826 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2827 stack space for register parameters is not pushed by the caller, but
2828 rather part of the fixed stack areas and hence not included in
2829 `current_function_outgoing_args_size'. Nevertheless, we must allow
2830 for it when allocating stack dynamic objects. */
2832 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2833 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2834 ((ACCUMULATE_OUTGOING_ARGS \
2835 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2836 + (STACK_POINTER_OFFSET)) \
2839 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2840 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2841 + (STACK_POINTER_OFFSET))
2845 /* On most machines, the CFA coincides with the first incoming parm. */
2847 #ifndef ARG_POINTER_CFA_OFFSET
2848 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2851 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just had
2852 its address taken. DECL is the decl for the object stored in the
2853 register, for later use if we do need to force REG into the stack.
2854 REG is overwritten by the MEM like in put_reg_into_stack. */
2857 gen_mem_addressof (reg, decl)
2861 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2864 /* If the original REG was a user-variable, then so is the REG whose
2865 address is being taken. Likewise for unchanging. */
2866 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2867 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2869 PUT_CODE (reg, MEM);
2873 tree type = TREE_TYPE (decl);
2875 PUT_MODE (reg, DECL_MODE (decl));
2876 MEM_VOLATILE_P (reg) = TREE_SIDE_EFFECTS (decl);
2877 MEM_SET_IN_STRUCT_P (reg, AGGREGATE_TYPE_P (type));
2878 MEM_ALIAS_SET (reg) = get_alias_set (decl);
2880 if (TREE_USED (decl) || DECL_INITIAL (decl) != 0)
2881 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), 0);
2885 /* We have no alias information about this newly created MEM. */
2886 MEM_ALIAS_SET (reg) = 0;
2888 fixup_var_refs (reg, GET_MODE (reg), 0, 0);
2894 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2897 flush_addressof (decl)
2900 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2901 && DECL_RTL (decl) != 0
2902 && GET_CODE (DECL_RTL (decl)) == MEM
2903 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2904 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2905 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2908 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2911 put_addressof_into_stack (r, ht)
2913 struct hash_table *ht;
2916 int volatile_p, used_p;
2918 rtx reg = XEXP (r, 0);
2920 if (GET_CODE (reg) != REG)
2923 decl = ADDRESSOF_DECL (r);
2926 type = TREE_TYPE (decl);
2927 volatile_p = (TREE_CODE (decl) != SAVE_EXPR
2928 && TREE_THIS_VOLATILE (decl));
2929 used_p = (TREE_USED (decl)
2930 || (TREE_CODE (decl) != SAVE_EXPR
2931 && DECL_INITIAL (decl) != 0));
2940 put_reg_into_stack (0, reg, type, GET_MODE (reg), GET_MODE (reg),
2941 volatile_p, ADDRESSOF_REGNO (r), used_p, ht);
2944 /* List of replacements made below in purge_addressof_1 when creating
2945 bitfield insertions. */
2946 static rtx purge_bitfield_addressof_replacements;
2948 /* List of replacements made below in purge_addressof_1 for patterns
2949 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2950 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2951 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2952 enough in complex cases, e.g. when some field values can be
2953 extracted by usage MEM with narrower mode. */
2954 static rtx purge_addressof_replacements;
2956 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2957 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2958 the stack. If the function returns FALSE then the replacement could not
2962 purge_addressof_1 (loc, insn, force, store, ht)
2966 struct hash_table *ht;
2974 /* Re-start here to avoid recursion in common cases. */
2981 code = GET_CODE (x);
2983 /* If we don't return in any of the cases below, we will recurse inside
2984 the RTX, which will normally result in any ADDRESSOF being forced into
2988 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1, ht);
2989 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0, ht);
2993 else if (code == ADDRESSOF && GET_CODE (XEXP (x, 0)) == MEM)
2995 /* We must create a copy of the rtx because it was created by
2996 overwriting a REG rtx which is always shared. */
2997 rtx sub = copy_rtx (XEXP (XEXP (x, 0), 0));
3000 if (validate_change (insn, loc, sub, 0)
3001 || validate_replace_rtx (x, sub, insn))
3005 sub = force_operand (sub, NULL_RTX);
3006 if (! validate_change (insn, loc, sub, 0)
3007 && ! validate_replace_rtx (x, sub, insn))
3010 insns = gen_sequence ();
3012 emit_insn_before (insns, insn);
3016 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
3018 rtx sub = XEXP (XEXP (x, 0), 0);
3021 if (GET_CODE (sub) == MEM)
3023 sub2 = gen_rtx_MEM (GET_MODE (x), copy_rtx (XEXP (sub, 0)));
3024 MEM_COPY_ATTRIBUTES (sub2, sub);
3027 else if (GET_CODE (sub) == REG
3028 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
3030 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
3032 int size_x, size_sub;
3036 /* When processing REG_NOTES look at the list of
3037 replacements done on the insn to find the register that X
3041 for (tem = purge_bitfield_addressof_replacements;
3043 tem = XEXP (XEXP (tem, 1), 1))
3044 if (rtx_equal_p (x, XEXP (tem, 0)))
3046 *loc = XEXP (XEXP (tem, 1), 0);
3050 /* See comment for purge_addressof_replacements. */
3051 for (tem = purge_addressof_replacements;
3053 tem = XEXP (XEXP (tem, 1), 1))
3054 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3056 rtx z = XEXP (XEXP (tem, 1), 0);
3058 if (GET_MODE (x) == GET_MODE (z)
3059 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
3060 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
3063 /* It can happen that the note may speak of things
3064 in a wider (or just different) mode than the
3065 code did. This is especially true of
3068 if (GET_CODE (z) == SUBREG && SUBREG_BYTE (z) == 0)
3071 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3072 && (GET_MODE_SIZE (GET_MODE (x))
3073 > GET_MODE_SIZE (GET_MODE (z))))
3075 /* This can occur as a result in invalid
3076 pointer casts, e.g. float f; ...
3077 *(long long int *)&f.
3078 ??? We could emit a warning here, but
3079 without a line number that wouldn't be
3081 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
3084 z = gen_lowpart (GET_MODE (x), z);
3090 /* Sometimes we may not be able to find the replacement. For
3091 example when the original insn was a MEM in a wider mode,
3092 and the note is part of a sign extension of a narrowed
3093 version of that MEM. Gcc testcase compile/990829-1.c can
3094 generate an example of this siutation. Rather than complain
3095 we return false, which will prompt our caller to remove the
3100 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3101 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3103 /* Don't even consider working with paradoxical subregs,
3104 or the moral equivalent seen here. */
3105 if (size_x <= size_sub
3106 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3108 /* Do a bitfield insertion to mirror what would happen
3115 rtx p = PREV_INSN (insn);
3118 val = gen_reg_rtx (GET_MODE (x));
3119 if (! validate_change (insn, loc, val, 0))
3121 /* Discard the current sequence and put the
3122 ADDRESSOF on stack. */
3126 seq = gen_sequence ();
3128 emit_insn_before (seq, insn);
3129 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3133 store_bit_field (sub, size_x, 0, GET_MODE (x),
3134 val, GET_MODE_SIZE (GET_MODE (sub)),
3135 GET_MODE_ALIGNMENT (GET_MODE (sub)));
3137 /* Make sure to unshare any shared rtl that store_bit_field
3138 might have created. */
3139 unshare_all_rtl_again (get_insns ());
3141 seq = gen_sequence ();
3143 p = emit_insn_after (seq, insn);
3144 if (NEXT_INSN (insn))
3145 compute_insns_for_mem (NEXT_INSN (insn),
3146 p ? NEXT_INSN (p) : NULL_RTX,
3151 rtx p = PREV_INSN (insn);
3154 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3155 GET_MODE (x), GET_MODE (x),
3156 GET_MODE_SIZE (GET_MODE (sub)),
3157 GET_MODE_SIZE (GET_MODE (sub)));
3159 if (! validate_change (insn, loc, val, 0))
3161 /* Discard the current sequence and put the
3162 ADDRESSOF on stack. */
3167 seq = gen_sequence ();
3169 emit_insn_before (seq, insn);
3170 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3174 /* Remember the replacement so that the same one can be done
3175 on the REG_NOTES. */
3176 purge_bitfield_addressof_replacements
3177 = gen_rtx_EXPR_LIST (VOIDmode, x,
3180 purge_bitfield_addressof_replacements));
3182 /* We replaced with a reg -- all done. */
3187 else if (validate_change (insn, loc, sub, 0))
3189 /* Remember the replacement so that the same one can be done
3190 on the REG_NOTES. */
3191 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3195 for (tem = purge_addressof_replacements;
3197 tem = XEXP (XEXP (tem, 1), 1))
3198 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3200 XEXP (XEXP (tem, 1), 0) = sub;
3203 purge_addressof_replacements
3204 = gen_rtx (EXPR_LIST, VOIDmode, XEXP (x, 0),
3205 gen_rtx_EXPR_LIST (VOIDmode, sub,
3206 purge_addressof_replacements));
3212 /* else give up and put it into the stack */
3215 else if (code == ADDRESSOF)
3217 put_addressof_into_stack (x, ht);
3220 else if (code == SET)
3222 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1, ht);
3223 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0, ht);
3227 /* Scan all subexpressions. */
3228 fmt = GET_RTX_FORMAT (code);
3229 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3232 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0, ht);
3233 else if (*fmt == 'E')
3234 for (j = 0; j < XVECLEN (x, i); j++)
3235 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0, ht);
3241 /* Return a new hash table entry in HT. */
3243 static struct hash_entry *
3244 insns_for_mem_newfunc (he, ht, k)
3245 struct hash_entry *he;
3246 struct hash_table *ht;
3247 hash_table_key k ATTRIBUTE_UNUSED;
3249 struct insns_for_mem_entry *ifmhe;
3253 ifmhe = ((struct insns_for_mem_entry *)
3254 hash_allocate (ht, sizeof (struct insns_for_mem_entry)));
3255 ifmhe->insns = NULL_RTX;
3260 /* Return a hash value for K, a REG. */
3262 static unsigned long
3263 insns_for_mem_hash (k)
3266 /* K is really a RTX. Just use the address as the hash value. */
3267 return (unsigned long) k;
3270 /* Return non-zero if K1 and K2 (two REGs) are the same. */
3273 insns_for_mem_comp (k1, k2)
3280 struct insns_for_mem_walk_info {
3281 /* The hash table that we are using to record which INSNs use which
3283 struct hash_table *ht;
3285 /* The INSN we are currently proessing. */
3288 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3289 to find the insns that use the REGs in the ADDRESSOFs. */
3293 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3294 that might be used in an ADDRESSOF expression, record this INSN in
3295 the hash table given by DATA (which is really a pointer to an
3296 insns_for_mem_walk_info structure). */
3299 insns_for_mem_walk (r, data)
3303 struct insns_for_mem_walk_info *ifmwi
3304 = (struct insns_for_mem_walk_info *) data;
3306 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3307 && GET_CODE (XEXP (*r, 0)) == REG)
3308 hash_lookup (ifmwi->ht, XEXP (*r, 0), /*create=*/1, /*copy=*/0);
3309 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3311 /* Lookup this MEM in the hashtable, creating it if necessary. */
3312 struct insns_for_mem_entry *ifme
3313 = (struct insns_for_mem_entry *) hash_lookup (ifmwi->ht,
3318 /* If we have not already recorded this INSN, do so now. Since
3319 we process the INSNs in order, we know that if we have
3320 recorded it it must be at the front of the list. */
3321 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3322 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3329 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3330 which REGs in HT. */
3333 compute_insns_for_mem (insns, last_insn, ht)
3336 struct hash_table *ht;
3339 struct insns_for_mem_walk_info ifmwi;
3342 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3343 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3347 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3351 /* Helper function for purge_addressof called through for_each_rtx.
3352 Returns true iff the rtl is an ADDRESSOF. */
3354 is_addressof (rtl, data)
3356 void *data ATTRIBUTE_UNUSED;
3358 return GET_CODE (*rtl) == ADDRESSOF;
3361 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3362 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3366 purge_addressof (insns)
3370 struct hash_table ht;
3372 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3373 requires a fixup pass over the instruction stream to correct
3374 INSNs that depended on the REG being a REG, and not a MEM. But,
3375 these fixup passes are slow. Furthermore, most MEMs are not
3376 mentioned in very many instructions. So, we speed up the process
3377 by pre-calculating which REGs occur in which INSNs; that allows
3378 us to perform the fixup passes much more quickly. */
3379 hash_table_init (&ht,
3380 insns_for_mem_newfunc,
3382 insns_for_mem_comp);
3383 compute_insns_for_mem (insns, NULL_RTX, &ht);
3385 for (insn = insns; insn; insn = NEXT_INSN (insn))
3386 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3387 || GET_CODE (insn) == CALL_INSN)
3389 if (! purge_addressof_1 (&PATTERN (insn), insn,
3390 asm_noperands (PATTERN (insn)) > 0, 0, &ht))
3391 /* If we could not replace the ADDRESSOFs in the insn,
3392 something is wrong. */
3395 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, &ht))
3397 /* If we could not replace the ADDRESSOFs in the insn's notes,
3398 we can just remove the offending notes instead. */
3401 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3403 /* If we find a REG_RETVAL note then the insn is a libcall.
3404 Such insns must have REG_EQUAL notes as well, in order
3405 for later passes of the compiler to work. So it is not
3406 safe to delete the notes here, and instead we abort. */
3407 if (REG_NOTE_KIND (note) == REG_RETVAL)
3409 if (for_each_rtx (¬e, is_addressof, NULL))
3410 remove_note (insn, note);
3416 hash_table_free (&ht);
3417 purge_bitfield_addressof_replacements = 0;
3418 purge_addressof_replacements = 0;
3420 /* REGs are shared. purge_addressof will destructively replace a REG
3421 with a MEM, which creates shared MEMs.
3423 Unfortunately, the children of put_reg_into_stack assume that MEMs
3424 referring to the same stack slot are shared (fixup_var_refs and
3425 the associated hash table code).
3427 So, we have to do another unsharing pass after we have flushed any
3428 REGs that had their address taken into the stack.
3430 It may be worth tracking whether or not we converted any REGs into
3431 MEMs to avoid this overhead when it is not needed. */
3432 unshare_all_rtl_again (get_insns ());
3435 /* Convert a SET of a hard subreg to a set of the appropriet hard
3436 register. A subroutine of purge_hard_subreg_sets. */
3439 purge_single_hard_subreg_set (pattern)
3442 rtx reg = SET_DEST (pattern);
3443 enum machine_mode mode = GET_MODE (SET_DEST (pattern));
3446 if (GET_CODE (reg) == SUBREG && GET_CODE (SUBREG_REG (reg)) == REG
3447 && REGNO (SUBREG_REG (reg)) < FIRST_PSEUDO_REGISTER)
3449 offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)),
3450 GET_MODE (SUBREG_REG (reg)),
3453 reg = SUBREG_REG (reg);
3457 if (REGNO (reg) < FIRST_PSEUDO_REGISTER)
3459 reg = gen_rtx_REG (mode, REGNO (reg) + offset);
3460 SET_DEST (pattern) = reg;
3464 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The
3465 only such SETs that we expect to see are those left in because
3466 integrate can't handle sets of parts of a return value register.
3468 We don't use alter_subreg because we only want to eliminate subregs
3469 of hard registers. */
3472 purge_hard_subreg_sets (insn)
3475 for (; insn; insn = NEXT_INSN (insn))
3479 rtx pattern = PATTERN (insn);
3480 switch (GET_CODE (pattern))
3483 if (GET_CODE (SET_DEST (pattern)) == SUBREG)
3484 purge_single_hard_subreg_set (pattern);
3489 for (j = XVECLEN (pattern, 0) - 1; j >= 0; j--)
3491 rtx inner_pattern = XVECEXP (pattern, 0, j);
3492 if (GET_CODE (inner_pattern) == SET
3493 && GET_CODE (SET_DEST (inner_pattern)) == SUBREG)
3494 purge_single_hard_subreg_set (inner_pattern);
3505 /* Pass through the INSNS of function FNDECL and convert virtual register
3506 references to hard register references. */
3509 instantiate_virtual_regs (fndecl, insns)
3516 /* Compute the offsets to use for this function. */
3517 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3518 var_offset = STARTING_FRAME_OFFSET;
3519 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3520 out_arg_offset = STACK_POINTER_OFFSET;
3521 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl);
3523 /* Scan all variables and parameters of this function. For each that is
3524 in memory, instantiate all virtual registers if the result is a valid
3525 address. If not, we do it later. That will handle most uses of virtual
3526 regs on many machines. */
3527 instantiate_decls (fndecl, 1);
3529 /* Initialize recognition, indicating that volatile is OK. */
3532 /* Scan through all the insns, instantiating every virtual register still
3534 for (insn = insns; insn; insn = NEXT_INSN (insn))
3535 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3536 || GET_CODE (insn) == CALL_INSN)
3538 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3539 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3540 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
3541 if (GET_CODE (insn) == CALL_INSN)
3542 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn),
3546 /* Instantiate the stack slots for the parm registers, for later use in
3547 addressof elimination. */
3548 for (i = 0; i < max_parm_reg; ++i)
3549 if (parm_reg_stack_loc[i])
3550 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3552 /* Now instantiate the remaining register equivalences for debugging info.
3553 These will not be valid addresses. */
3554 instantiate_decls (fndecl, 0);
3556 /* Indicate that, from now on, assign_stack_local should use
3557 frame_pointer_rtx. */
3558 virtuals_instantiated = 1;
3561 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3562 all virtual registers in their DECL_RTL's.
3564 If VALID_ONLY, do this only if the resulting address is still valid.
3565 Otherwise, always do it. */
3568 instantiate_decls (fndecl, valid_only)
3574 /* Process all parameters of the function. */
3575 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3577 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3579 instantiate_decl (DECL_RTL (decl), size, valid_only);
3581 /* If the parameter was promoted, then the incoming RTL mode may be
3582 larger than the declared type size. We must use the larger of
3584 size = MAX (GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl))), size);
3585 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3588 /* Now process all variables defined in the function or its subblocks. */
3589 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3592 /* Subroutine of instantiate_decls: Process all decls in the given
3593 BLOCK node and all its subblocks. */
3596 instantiate_decls_1 (let, valid_only)
3602 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3603 if (DECL_RTL_SET_P (t))
3604 instantiate_decl (DECL_RTL (t),
3605 int_size_in_bytes (TREE_TYPE (t)),
3608 /* Process all subblocks. */
3609 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3610 instantiate_decls_1 (t, valid_only);
3613 /* Subroutine of the preceding procedures: Given RTL representing a
3614 decl and the size of the object, do any instantiation required.
3616 If VALID_ONLY is non-zero, it means that the RTL should only be
3617 changed if the new address is valid. */
3620 instantiate_decl (x, size, valid_only)
3625 enum machine_mode mode;
3628 /* If this is not a MEM, no need to do anything. Similarly if the
3629 address is a constant or a register that is not a virtual register. */
3631 if (x == 0 || GET_CODE (x) != MEM)
3635 if (CONSTANT_P (addr)
3636 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3637 || (GET_CODE (addr) == REG
3638 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3639 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3642 /* If we should only do this if the address is valid, copy the address.
3643 We need to do this so we can undo any changes that might make the
3644 address invalid. This copy is unfortunate, but probably can't be
3648 addr = copy_rtx (addr);
3650 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3652 if (valid_only && size >= 0)
3654 unsigned HOST_WIDE_INT decl_size = size;
3656 /* Now verify that the resulting address is valid for every integer or
3657 floating-point mode up to and including SIZE bytes long. We do this
3658 since the object might be accessed in any mode and frame addresses
3661 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3662 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3663 mode = GET_MODE_WIDER_MODE (mode))
3664 if (! memory_address_p (mode, addr))
3667 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3668 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3669 mode = GET_MODE_WIDER_MODE (mode))
3670 if (! memory_address_p (mode, addr))
3674 /* Put back the address now that we have updated it and we either know
3675 it is valid or we don't care whether it is valid. */
3680 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
3681 is a virtual register, return the requivalent hard register and set the
3682 offset indirectly through the pointer. Otherwise, return 0. */
3685 instantiate_new_reg (x, poffset)
3687 HOST_WIDE_INT *poffset;
3690 HOST_WIDE_INT offset;
3692 if (x == virtual_incoming_args_rtx)
3693 new = arg_pointer_rtx, offset = in_arg_offset;
3694 else if (x == virtual_stack_vars_rtx)
3695 new = frame_pointer_rtx, offset = var_offset;
3696 else if (x == virtual_stack_dynamic_rtx)
3697 new = stack_pointer_rtx, offset = dynamic_offset;
3698 else if (x == virtual_outgoing_args_rtx)
3699 new = stack_pointer_rtx, offset = out_arg_offset;
3700 else if (x == virtual_cfa_rtx)
3701 new = arg_pointer_rtx, offset = cfa_offset;
3709 /* Given a pointer to a piece of rtx and an optional pointer to the
3710 containing object, instantiate any virtual registers present in it.
3712 If EXTRA_INSNS, we always do the replacement and generate
3713 any extra insns before OBJECT. If it zero, we do nothing if replacement
3716 Return 1 if we either had nothing to do or if we were able to do the
3717 needed replacement. Return 0 otherwise; we only return zero if
3718 EXTRA_INSNS is zero.
3720 We first try some simple transformations to avoid the creation of extra
3724 instantiate_virtual_regs_1 (loc, object, extra_insns)
3732 HOST_WIDE_INT offset = 0;
3738 /* Re-start here to avoid recursion in common cases. */
3745 code = GET_CODE (x);
3747 /* Check for some special cases. */
3764 /* We are allowed to set the virtual registers. This means that
3765 the actual register should receive the source minus the
3766 appropriate offset. This is used, for example, in the handling
3767 of non-local gotos. */
3768 if ((new = instantiate_new_reg (SET_DEST (x), &offset)) != 0)
3770 rtx src = SET_SRC (x);
3772 /* We are setting the register, not using it, so the relevant
3773 offset is the negative of the offset to use were we using
3776 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3778 /* The only valid sources here are PLUS or REG. Just do
3779 the simplest possible thing to handle them. */
3780 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3784 if (GET_CODE (src) != REG)
3785 temp = force_operand (src, NULL_RTX);
3788 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3792 emit_insns_before (seq, object);
3795 if (! validate_change (object, &SET_SRC (x), temp, 0)
3802 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3807 /* Handle special case of virtual register plus constant. */
3808 if (CONSTANT_P (XEXP (x, 1)))
3810 rtx old, new_offset;
3812 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3813 if (GET_CODE (XEXP (x, 0)) == PLUS)
3815 if ((new = instantiate_new_reg (XEXP (XEXP (x, 0), 0), &offset)))
3817 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3819 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3828 #ifdef POINTERS_EXTEND_UNSIGNED
3829 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
3830 we can commute the PLUS and SUBREG because pointers into the
3831 frame are well-behaved. */
3832 else if (GET_CODE (XEXP (x, 0)) == SUBREG && GET_MODE (x) == ptr_mode
3833 && GET_CODE (XEXP (x, 1)) == CONST_INT
3835 = instantiate_new_reg (SUBREG_REG (XEXP (x, 0)),
3837 && validate_change (object, loc,
3838 plus_constant (gen_lowpart (ptr_mode,
3841 + INTVAL (XEXP (x, 1))),
3845 else if ((new = instantiate_new_reg (XEXP (x, 0), &offset)) == 0)
3847 /* We know the second operand is a constant. Unless the
3848 first operand is a REG (which has been already checked),
3849 it needs to be checked. */
3850 if (GET_CODE (XEXP (x, 0)) != REG)
3858 new_offset = plus_constant (XEXP (x, 1), offset);
3860 /* If the new constant is zero, try to replace the sum with just
3862 if (new_offset == const0_rtx
3863 && validate_change (object, loc, new, 0))
3866 /* Next try to replace the register and new offset.
3867 There are two changes to validate here and we can't assume that
3868 in the case of old offset equals new just changing the register
3869 will yield a valid insn. In the interests of a little efficiency,
3870 however, we only call validate change once (we don't queue up the
3871 changes and then call apply_change_group). */
3875 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3876 : (XEXP (x, 0) = new,
3877 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3885 /* Otherwise copy the new constant into a register and replace
3886 constant with that register. */
3887 temp = gen_reg_rtx (Pmode);
3889 if (validate_change (object, &XEXP (x, 1), temp, 0))
3890 emit_insn_before (gen_move_insn (temp, new_offset), object);
3893 /* If that didn't work, replace this expression with a
3894 register containing the sum. */
3897 new = gen_rtx_PLUS (Pmode, new, new_offset);
3900 temp = force_operand (new, NULL_RTX);
3904 emit_insns_before (seq, object);
3905 if (! validate_change (object, loc, temp, 0)
3906 && ! validate_replace_rtx (x, temp, object))
3914 /* Fall through to generic two-operand expression case. */
3920 case DIV: case UDIV:
3921 case MOD: case UMOD:
3922 case AND: case IOR: case XOR:
3923 case ROTATERT: case ROTATE:
3924 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3926 case GE: case GT: case GEU: case GTU:
3927 case LE: case LT: case LEU: case LTU:
3928 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3929 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3934 /* Most cases of MEM that convert to valid addresses have already been
3935 handled by our scan of decls. The only special handling we
3936 need here is to make a copy of the rtx to ensure it isn't being
3937 shared if we have to change it to a pseudo.
3939 If the rtx is a simple reference to an address via a virtual register,
3940 it can potentially be shared. In such cases, first try to make it
3941 a valid address, which can also be shared. Otherwise, copy it and
3944 First check for common cases that need no processing. These are
3945 usually due to instantiation already being done on a previous instance
3949 if (CONSTANT_ADDRESS_P (temp)
3950 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3951 || temp == arg_pointer_rtx
3953 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3954 || temp == hard_frame_pointer_rtx
3956 || temp == frame_pointer_rtx)
3959 if (GET_CODE (temp) == PLUS
3960 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3961 && (XEXP (temp, 0) == frame_pointer_rtx
3962 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3963 || XEXP (temp, 0) == hard_frame_pointer_rtx
3965 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3966 || XEXP (temp, 0) == arg_pointer_rtx
3971 if (temp == virtual_stack_vars_rtx
3972 || temp == virtual_incoming_args_rtx
3973 || (GET_CODE (temp) == PLUS
3974 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3975 && (XEXP (temp, 0) == virtual_stack_vars_rtx
3976 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
3978 /* This MEM may be shared. If the substitution can be done without
3979 the need to generate new pseudos, we want to do it in place
3980 so all copies of the shared rtx benefit. The call below will
3981 only make substitutions if the resulting address is still
3984 Note that we cannot pass X as the object in the recursive call
3985 since the insn being processed may not allow all valid
3986 addresses. However, if we were not passed on object, we can
3987 only modify X without copying it if X will have a valid
3990 ??? Also note that this can still lose if OBJECT is an insn that
3991 has less restrictions on an address that some other insn.
3992 In that case, we will modify the shared address. This case
3993 doesn't seem very likely, though. One case where this could
3994 happen is in the case of a USE or CLOBBER reference, but we
3995 take care of that below. */
3997 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
3998 object ? object : x, 0))
4001 /* Otherwise make a copy and process that copy. We copy the entire
4002 RTL expression since it might be a PLUS which could also be
4004 *loc = x = copy_rtx (x);
4007 /* Fall through to generic unary operation case. */
4009 case STRICT_LOW_PART:
4011 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
4012 case SIGN_EXTEND: case ZERO_EXTEND:
4013 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
4014 case FLOAT: case FIX:
4015 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
4019 /* These case either have just one operand or we know that we need not
4020 check the rest of the operands. */
4026 /* If the operand is a MEM, see if the change is a valid MEM. If not,
4027 go ahead and make the invalid one, but do it to a copy. For a REG,
4028 just make the recursive call, since there's no chance of a problem. */
4030 if ((GET_CODE (XEXP (x, 0)) == MEM
4031 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
4033 || (GET_CODE (XEXP (x, 0)) == REG
4034 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
4037 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
4042 /* Try to replace with a PLUS. If that doesn't work, compute the sum
4043 in front of this insn and substitute the temporary. */
4044 if ((new = instantiate_new_reg (x, &offset)) != 0)
4046 temp = plus_constant (new, offset);
4047 if (!validate_change (object, loc, temp, 0))
4053 temp = force_operand (temp, NULL_RTX);
4057 emit_insns_before (seq, object);
4058 if (! validate_change (object, loc, temp, 0)
4059 && ! validate_replace_rtx (x, temp, object))
4067 if (GET_CODE (XEXP (x, 0)) == REG)
4070 else if (GET_CODE (XEXP (x, 0)) == MEM)
4072 /* If we have a (addressof (mem ..)), do any instantiation inside
4073 since we know we'll be making the inside valid when we finally
4074 remove the ADDRESSOF. */
4075 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
4084 /* Scan all subexpressions. */
4085 fmt = GET_RTX_FORMAT (code);
4086 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
4089 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
4092 else if (*fmt == 'E')
4093 for (j = 0; j < XVECLEN (x, i); j++)
4094 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
4101 /* Optimization: assuming this function does not receive nonlocal gotos,
4102 delete the handlers for such, as well as the insns to establish
4103 and disestablish them. */
4109 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4111 /* Delete the handler by turning off the flag that would
4112 prevent jump_optimize from deleting it.
4113 Also permit deletion of the nonlocal labels themselves
4114 if nothing local refers to them. */
4115 if (GET_CODE (insn) == CODE_LABEL)
4119 LABEL_PRESERVE_P (insn) = 0;
4121 /* Remove it from the nonlocal_label list, to avoid confusing
4123 for (t = nonlocal_labels, last_t = 0; t;
4124 last_t = t, t = TREE_CHAIN (t))
4125 if (DECL_RTL (TREE_VALUE (t)) == insn)
4130 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
4132 TREE_CHAIN (last_t) = TREE_CHAIN (t);
4135 if (GET_CODE (insn) == INSN)
4139 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
4140 if (reg_mentioned_p (t, PATTERN (insn)))
4146 || (nonlocal_goto_stack_level != 0
4147 && reg_mentioned_p (nonlocal_goto_stack_level,
4157 return max_parm_reg;
4160 /* Return the first insn following those generated by `assign_parms'. */
4163 get_first_nonparm_insn ()
4166 return NEXT_INSN (last_parm_insn);
4167 return get_insns ();
4170 /* Return the first NOTE_INSN_BLOCK_BEG note in the function.
4171 Crash if there is none. */
4174 get_first_block_beg ()
4176 register rtx searcher;
4177 register rtx insn = get_first_nonparm_insn ();
4179 for (searcher = insn; searcher; searcher = NEXT_INSN (searcher))
4180 if (GET_CODE (searcher) == NOTE
4181 && NOTE_LINE_NUMBER (searcher) == NOTE_INSN_BLOCK_BEG)
4184 abort (); /* Invalid call to this function. (See comments above.) */
4188 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4189 This means a type for which function calls must pass an address to the
4190 function or get an address back from the function.
4191 EXP may be a type node or an expression (whose type is tested). */
4194 aggregate_value_p (exp)
4197 int i, regno, nregs;
4200 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4202 if (TREE_CODE (type) == VOID_TYPE)
4204 if (RETURN_IN_MEMORY (type))
4206 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4207 and thus can't be returned in registers. */
4208 if (TREE_ADDRESSABLE (type))
4210 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4212 /* Make sure we have suitable call-clobbered regs to return
4213 the value in; if not, we must return it in memory. */
4214 reg = hard_function_value (type, 0, 0);
4216 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4218 if (GET_CODE (reg) != REG)
4221 regno = REGNO (reg);
4222 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
4223 for (i = 0; i < nregs; i++)
4224 if (! call_used_regs[regno + i])
4229 /* Assign RTL expressions to the function's parameters.
4230 This may involve copying them into registers and using
4231 those registers as the RTL for them. */
4234 assign_parms (fndecl)
4238 register rtx entry_parm = 0;
4239 register rtx stack_parm = 0;
4240 CUMULATIVE_ARGS args_so_far;
4241 enum machine_mode promoted_mode, passed_mode;
4242 enum machine_mode nominal_mode, promoted_nominal_mode;
4244 /* Total space needed so far for args on the stack,
4245 given as a constant and a tree-expression. */
4246 struct args_size stack_args_size;
4247 tree fntype = TREE_TYPE (fndecl);
4248 tree fnargs = DECL_ARGUMENTS (fndecl);
4249 /* This is used for the arg pointer when referring to stack args. */
4250 rtx internal_arg_pointer;
4251 /* This is a dummy PARM_DECL that we used for the function result if
4252 the function returns a structure. */
4253 tree function_result_decl = 0;
4254 #ifdef SETUP_INCOMING_VARARGS
4255 int varargs_setup = 0;
4257 rtx conversion_insns = 0;
4258 struct args_size alignment_pad;
4260 /* Nonzero if the last arg is named `__builtin_va_alist',
4261 which is used on some machines for old-fashioned non-ANSI varargs.h;
4262 this should be stuck onto the stack as if it had arrived there. */
4264 = (current_function_varargs
4266 && (parm = tree_last (fnargs)) != 0
4268 && (! strcmp (IDENTIFIER_POINTER (DECL_NAME (parm)),
4269 "__builtin_va_alist")));
4271 /* Nonzero if function takes extra anonymous args.
4272 This means the last named arg must be on the stack
4273 right before the anonymous ones. */
4275 = (TYPE_ARG_TYPES (fntype) != 0
4276 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4277 != void_type_node));
4279 current_function_stdarg = stdarg;
4281 /* If the reg that the virtual arg pointer will be translated into is
4282 not a fixed reg or is the stack pointer, make a copy of the virtual
4283 arg pointer, and address parms via the copy. The frame pointer is
4284 considered fixed even though it is not marked as such.
4286 The second time through, simply use ap to avoid generating rtx. */
4288 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4289 || ! (fixed_regs[ARG_POINTER_REGNUM]
4290 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4291 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4293 internal_arg_pointer = virtual_incoming_args_rtx;
4294 current_function_internal_arg_pointer = internal_arg_pointer;
4296 stack_args_size.constant = 0;
4297 stack_args_size.var = 0;
4299 /* If struct value address is treated as the first argument, make it so. */
4300 if (aggregate_value_p (DECL_RESULT (fndecl))
4301 && ! current_function_returns_pcc_struct
4302 && struct_value_incoming_rtx == 0)
4304 tree type = build_pointer_type (TREE_TYPE (fntype));
4306 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4308 DECL_ARG_TYPE (function_result_decl) = type;
4309 TREE_CHAIN (function_result_decl) = fnargs;
4310 fnargs = function_result_decl;
4313 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4314 parm_reg_stack_loc = (rtx *) xcalloc (max_parm_reg, sizeof (rtx));
4316 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4317 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4319 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, 0);
4322 /* We haven't yet found an argument that we must push and pretend the
4324 current_function_pretend_args_size = 0;
4326 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4328 struct args_size stack_offset;
4329 struct args_size arg_size;
4330 int passed_pointer = 0;
4331 int did_conversion = 0;
4332 tree passed_type = DECL_ARG_TYPE (parm);
4333 tree nominal_type = TREE_TYPE (parm);
4336 /* Set LAST_NAMED if this is last named arg before some
4338 int last_named = ((TREE_CHAIN (parm) == 0
4339 || DECL_NAME (TREE_CHAIN (parm)) == 0)
4340 && (stdarg || current_function_varargs));
4341 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4342 most machines, if this is a varargs/stdarg function, then we treat
4343 the last named arg as if it were anonymous too. */
4344 int named_arg = STRICT_ARGUMENT_NAMING ? 1 : ! last_named;
4346 if (TREE_TYPE (parm) == error_mark_node
4347 /* This can happen after weird syntax errors
4348 or if an enum type is defined among the parms. */
4349 || TREE_CODE (parm) != PARM_DECL
4350 || passed_type == NULL)
4352 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx));
4353 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4354 TREE_USED (parm) = 1;
4358 /* For varargs.h function, save info about regs and stack space
4359 used by the individual args, not including the va_alist arg. */
4360 if (hide_last_arg && last_named)
4361 current_function_args_info = args_so_far;
4363 /* Find mode of arg as it is passed, and mode of arg
4364 as it should be during execution of this function. */
4365 passed_mode = TYPE_MODE (passed_type);
4366 nominal_mode = TYPE_MODE (nominal_type);
4368 /* If the parm's mode is VOID, its value doesn't matter,
4369 and avoid the usual things like emit_move_insn that could crash. */
4370 if (nominal_mode == VOIDmode)
4372 SET_DECL_RTL (parm, const0_rtx);
4373 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4377 /* If the parm is to be passed as a transparent union, use the
4378 type of the first field for the tests below. We have already
4379 verified that the modes are the same. */
4380 if (DECL_TRANSPARENT_UNION (parm)
4381 || (TREE_CODE (passed_type) == UNION_TYPE
4382 && TYPE_TRANSPARENT_UNION (passed_type)))
4383 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4385 /* See if this arg was passed by invisible reference. It is if
4386 it is an object whose size depends on the contents of the
4387 object itself or if the machine requires these objects be passed
4390 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
4391 && contains_placeholder_p (TYPE_SIZE (passed_type)))
4392 || TREE_ADDRESSABLE (passed_type)
4393 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4394 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4395 passed_type, named_arg)
4399 passed_type = nominal_type = build_pointer_type (passed_type);
4401 passed_mode = nominal_mode = Pmode;
4404 promoted_mode = passed_mode;
4406 #ifdef PROMOTE_FUNCTION_ARGS
4407 /* Compute the mode in which the arg is actually extended to. */
4408 unsignedp = TREE_UNSIGNED (passed_type);
4409 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4412 /* Let machine desc say which reg (if any) the parm arrives in.
4413 0 means it arrives on the stack. */
4414 #ifdef FUNCTION_INCOMING_ARG
4415 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4416 passed_type, named_arg);
4418 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4419 passed_type, named_arg);
4422 if (entry_parm == 0)
4423 promoted_mode = passed_mode;
4425 #ifdef SETUP_INCOMING_VARARGS
4426 /* If this is the last named parameter, do any required setup for
4427 varargs or stdargs. We need to know about the case of this being an
4428 addressable type, in which case we skip the registers it
4429 would have arrived in.
4431 For stdargs, LAST_NAMED will be set for two parameters, the one that
4432 is actually the last named, and the dummy parameter. We only
4433 want to do this action once.
4435 Also, indicate when RTL generation is to be suppressed. */
4436 if (last_named && !varargs_setup)
4438 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
4439 current_function_pretend_args_size, 0);
4444 /* Determine parm's home in the stack,
4445 in case it arrives in the stack or we should pretend it did.
4447 Compute the stack position and rtx where the argument arrives
4450 There is one complexity here: If this was a parameter that would
4451 have been passed in registers, but wasn't only because it is
4452 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4453 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4454 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4455 0 as it was the previous time. */
4457 pretend_named = named_arg || PRETEND_OUTGOING_VARARGS_NAMED;
4458 locate_and_pad_parm (promoted_mode, passed_type,
4459 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4462 #ifdef FUNCTION_INCOMING_ARG
4463 FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4465 pretend_named) != 0,
4467 FUNCTION_ARG (args_so_far, promoted_mode,
4469 pretend_named) != 0,
4472 fndecl, &stack_args_size, &stack_offset, &arg_size,
4476 rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
4478 if (offset_rtx == const0_rtx)
4479 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4481 stack_parm = gen_rtx_MEM (promoted_mode,
4482 gen_rtx_PLUS (Pmode,
4483 internal_arg_pointer,
4486 set_mem_attributes (stack_parm, parm, 1);
4489 /* If this parameter was passed both in registers and in the stack,
4490 use the copy on the stack. */
4491 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4494 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4495 /* If this parm was passed part in regs and part in memory,
4496 pretend it arrived entirely in memory
4497 by pushing the register-part onto the stack.
4499 In the special case of a DImode or DFmode that is split,
4500 we could put it together in a pseudoreg directly,
4501 but for now that's not worth bothering with. */
4505 int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4506 passed_type, named_arg);
4510 current_function_pretend_args_size
4511 = (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
4512 / (PARM_BOUNDARY / BITS_PER_UNIT)
4513 * (PARM_BOUNDARY / BITS_PER_UNIT));
4515 /* Handle calls that pass values in multiple non-contiguous
4516 locations. The Irix 6 ABI has examples of this. */
4517 if (GET_CODE (entry_parm) == PARALLEL)
4518 emit_group_store (validize_mem (stack_parm), entry_parm,
4519 int_size_in_bytes (TREE_TYPE (parm)),
4520 TYPE_ALIGN (TREE_TYPE (parm)));
4523 move_block_from_reg (REGNO (entry_parm),
4524 validize_mem (stack_parm), nregs,
4525 int_size_in_bytes (TREE_TYPE (parm)));
4527 entry_parm = stack_parm;
4532 /* If we didn't decide this parm came in a register,
4533 by default it came on the stack. */
4534 if (entry_parm == 0)
4535 entry_parm = stack_parm;
4537 /* Record permanently how this parm was passed. */
4538 DECL_INCOMING_RTL (parm) = entry_parm;
4540 /* If there is actually space on the stack for this parm,
4541 count it in stack_args_size; otherwise set stack_parm to 0
4542 to indicate there is no preallocated stack slot for the parm. */
4544 if (entry_parm == stack_parm
4545 || (GET_CODE (entry_parm) == PARALLEL
4546 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4547 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4548 /* On some machines, even if a parm value arrives in a register
4549 there is still an (uninitialized) stack slot allocated for it.
4551 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4552 whether this parameter already has a stack slot allocated,
4553 because an arg block exists only if current_function_args_size
4554 is larger than some threshold, and we haven't calculated that
4555 yet. So, for now, we just assume that stack slots never exist
4557 || REG_PARM_STACK_SPACE (fndecl) > 0
4561 stack_args_size.constant += arg_size.constant;
4563 ADD_PARM_SIZE (stack_args_size, arg_size.var);
4566 /* No stack slot was pushed for this parm. */
4569 /* Update info on where next arg arrives in registers. */
4571 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4572 passed_type, named_arg);
4574 /* If we can't trust the parm stack slot to be aligned enough
4575 for its ultimate type, don't use that slot after entry.
4576 We'll make another stack slot, if we need one. */
4578 unsigned int thisparm_boundary
4579 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4581 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4585 /* If parm was passed in memory, and we need to convert it on entry,
4586 don't store it back in that same slot. */
4588 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4591 /* When an argument is passed in multiple locations, we can't
4592 make use of this information, but we can save some copying if
4593 the whole argument is passed in a single register. */
4594 if (GET_CODE (entry_parm) == PARALLEL
4595 && nominal_mode != BLKmode && passed_mode != BLKmode)
4597 int i, len = XVECLEN (entry_parm, 0);
4599 for (i = 0; i < len; i++)
4600 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
4601 && GET_CODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) == REG
4602 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
4604 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
4606 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
4607 DECL_INCOMING_RTL (parm) = entry_parm;
4612 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4613 in the mode in which it arrives.
4614 STACK_PARM is an RTX for a stack slot where the parameter can live
4615 during the function (in case we want to put it there).
4616 STACK_PARM is 0 if no stack slot was pushed for it.
4618 Now output code if necessary to convert ENTRY_PARM to
4619 the type in which this function declares it,
4620 and store that result in an appropriate place,
4621 which may be a pseudo reg, may be STACK_PARM,
4622 or may be a local stack slot if STACK_PARM is 0.
4624 Set DECL_RTL to that place. */
4626 if (nominal_mode == BLKmode || GET_CODE (entry_parm) == PARALLEL)
4628 /* If a BLKmode arrives in registers, copy it to a stack slot.
4629 Handle calls that pass values in multiple non-contiguous
4630 locations. The Irix 6 ABI has examples of this. */
4631 if (GET_CODE (entry_parm) == REG
4632 || GET_CODE (entry_parm) == PARALLEL)
4635 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
4638 /* Note that we will be storing an integral number of words.
4639 So we have to be careful to ensure that we allocate an
4640 integral number of words. We do this below in the
4641 assign_stack_local if space was not allocated in the argument
4642 list. If it was, this will not work if PARM_BOUNDARY is not
4643 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4644 if it becomes a problem. */
4646 if (stack_parm == 0)
4649 = assign_stack_local (GET_MODE (entry_parm),
4651 set_mem_attributes (stack_parm, parm, 1);
4654 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4657 /* Handle calls that pass values in multiple non-contiguous
4658 locations. The Irix 6 ABI has examples of this. */
4659 if (GET_CODE (entry_parm) == PARALLEL)
4660 emit_group_store (validize_mem (stack_parm), entry_parm,
4661 int_size_in_bytes (TREE_TYPE (parm)),
4662 TYPE_ALIGN (TREE_TYPE (parm)));
4664 move_block_from_reg (REGNO (entry_parm),
4665 validize_mem (stack_parm),
4666 size_stored / UNITS_PER_WORD,
4667 int_size_in_bytes (TREE_TYPE (parm)));
4669 SET_DECL_RTL (parm, stack_parm);
4671 else if (! ((! optimize
4672 && ! DECL_REGISTER (parm)
4673 && ! DECL_INLINE (fndecl))
4674 || TREE_SIDE_EFFECTS (parm)
4675 /* If -ffloat-store specified, don't put explicit
4676 float variables into registers. */
4677 || (flag_float_store
4678 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4679 /* Always assign pseudo to structure return or item passed
4680 by invisible reference. */
4681 || passed_pointer || parm == function_result_decl)
4683 /* Store the parm in a pseudoregister during the function, but we
4684 may need to do it in a wider mode. */
4686 register rtx parmreg;
4687 unsigned int regno, regnoi = 0, regnor = 0;
4689 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4691 promoted_nominal_mode
4692 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4694 parmreg = gen_reg_rtx (promoted_nominal_mode);
4695 mark_user_reg (parmreg);
4697 /* If this was an item that we received a pointer to, set DECL_RTL
4702 gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)),
4704 set_mem_attributes (DECL_RTL (parm), parm, 1);
4708 SET_DECL_RTL (parm, parmreg);
4709 maybe_set_unchanging (DECL_RTL (parm), parm);
4712 /* Copy the value into the register. */
4713 if (nominal_mode != passed_mode
4714 || promoted_nominal_mode != promoted_mode)
4717 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4718 mode, by the caller. We now have to convert it to
4719 NOMINAL_MODE, if different. However, PARMREG may be in
4720 a different mode than NOMINAL_MODE if it is being stored
4723 If ENTRY_PARM is a hard register, it might be in a register
4724 not valid for operating in its mode (e.g., an odd-numbered
4725 register for a DFmode). In that case, moves are the only
4726 thing valid, so we can't do a convert from there. This
4727 occurs when the calling sequence allow such misaligned
4730 In addition, the conversion may involve a call, which could
4731 clobber parameters which haven't been copied to pseudo
4732 registers yet. Therefore, we must first copy the parm to
4733 a pseudo reg here, and save the conversion until after all
4734 parameters have been moved. */
4736 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4738 emit_move_insn (tempreg, validize_mem (entry_parm));
4740 push_to_sequence (conversion_insns);
4741 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4743 if (GET_CODE (tempreg) == SUBREG
4744 && GET_MODE (tempreg) == nominal_mode
4745 && GET_CODE (SUBREG_REG (tempreg)) == REG
4746 && nominal_mode == passed_mode
4747 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm)
4748 && GET_MODE_SIZE (GET_MODE (tempreg))
4749 < GET_MODE_SIZE (GET_MODE (entry_parm)))
4751 /* The argument is already sign/zero extended, so note it
4753 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
4754 SUBREG_PROMOTED_UNSIGNED_P (tempreg) = unsignedp;
4757 /* TREE_USED gets set erroneously during expand_assignment. */
4758 save_tree_used = TREE_USED (parm);
4759 expand_assignment (parm,
4760 make_tree (nominal_type, tempreg), 0, 0);
4761 TREE_USED (parm) = save_tree_used;
4762 conversion_insns = get_insns ();
4767 emit_move_insn (parmreg, validize_mem (entry_parm));
4769 /* If we were passed a pointer but the actual value
4770 can safely live in a register, put it in one. */
4771 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4773 && ! DECL_REGISTER (parm)
4774 && ! DECL_INLINE (fndecl))
4775 || TREE_SIDE_EFFECTS (parm)
4776 /* If -ffloat-store specified, don't put explicit
4777 float variables into registers. */
4778 || (flag_float_store
4779 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE)))
4781 /* We can't use nominal_mode, because it will have been set to
4782 Pmode above. We must use the actual mode of the parm. */
4783 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4784 mark_user_reg (parmreg);
4785 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
4787 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
4788 int unsigned_p = TREE_UNSIGNED (TREE_TYPE (parm));
4789 push_to_sequence (conversion_insns);
4790 emit_move_insn (tempreg, DECL_RTL (parm));
4792 convert_to_mode (GET_MODE (parmreg),
4795 emit_move_insn (parmreg, DECL_RTL (parm));
4796 conversion_insns = get_insns();
4801 emit_move_insn (parmreg, DECL_RTL (parm));
4802 SET_DECL_RTL (parm, parmreg);
4803 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4807 #ifdef FUNCTION_ARG_CALLEE_COPIES
4808 /* If we are passed an arg by reference and it is our responsibility
4809 to make a copy, do it now.
4810 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4811 original argument, so we must recreate them in the call to
4812 FUNCTION_ARG_CALLEE_COPIES. */
4813 /* ??? Later add code to handle the case that if the argument isn't
4814 modified, don't do the copy. */
4816 else if (passed_pointer
4817 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4818 TYPE_MODE (DECL_ARG_TYPE (parm)),
4819 DECL_ARG_TYPE (parm),
4821 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4824 tree type = DECL_ARG_TYPE (parm);
4826 /* This sequence may involve a library call perhaps clobbering
4827 registers that haven't been copied to pseudos yet. */
4829 push_to_sequence (conversion_insns);
4831 if (!COMPLETE_TYPE_P (type)
4832 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4833 /* This is a variable sized object. */
4834 copy = gen_rtx_MEM (BLKmode,
4835 allocate_dynamic_stack_space
4836 (expr_size (parm), NULL_RTX,
4837 TYPE_ALIGN (type)));
4839 copy = assign_stack_temp (TYPE_MODE (type),
4840 int_size_in_bytes (type), 1);
4841 set_mem_attributes (copy, parm, 1);
4843 store_expr (parm, copy, 0);
4844 emit_move_insn (parmreg, XEXP (copy, 0));
4845 if (current_function_check_memory_usage)
4846 emit_library_call (chkr_set_right_libfunc,
4847 LCT_CONST_MAKE_BLOCK, VOIDmode, 3,
4848 XEXP (copy, 0), Pmode,
4849 GEN_INT (int_size_in_bytes (type)),
4850 TYPE_MODE (sizetype),
4851 GEN_INT (MEMORY_USE_RW),
4852 TYPE_MODE (integer_type_node));
4853 conversion_insns = get_insns ();
4857 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4859 /* In any case, record the parm's desired stack location
4860 in case we later discover it must live in the stack.
4862 If it is a COMPLEX value, store the stack location for both
4865 if (GET_CODE (parmreg) == CONCAT)
4866 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4868 regno = REGNO (parmreg);
4870 if (regno >= max_parm_reg)
4873 int old_max_parm_reg = max_parm_reg;
4875 /* It's slow to expand this one register at a time,
4876 but it's also rare and we need max_parm_reg to be
4877 precisely correct. */
4878 max_parm_reg = regno + 1;
4879 new = (rtx *) xrealloc (parm_reg_stack_loc,
4880 max_parm_reg * sizeof (rtx));
4881 memset ((char *) (new + old_max_parm_reg), 0,
4882 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4883 parm_reg_stack_loc = new;
4886 if (GET_CODE (parmreg) == CONCAT)
4888 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
4890 regnor = REGNO (gen_realpart (submode, parmreg));
4891 regnoi = REGNO (gen_imagpart (submode, parmreg));
4893 if (stack_parm != 0)
4895 parm_reg_stack_loc[regnor]
4896 = gen_realpart (submode, stack_parm);
4897 parm_reg_stack_loc[regnoi]
4898 = gen_imagpart (submode, stack_parm);
4902 parm_reg_stack_loc[regnor] = 0;
4903 parm_reg_stack_loc[regnoi] = 0;
4907 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
4909 /* Mark the register as eliminable if we did no conversion
4910 and it was copied from memory at a fixed offset,
4911 and the arg pointer was not copied to a pseudo-reg.
4912 If the arg pointer is a pseudo reg or the offset formed
4913 an invalid address, such memory-equivalences
4914 as we make here would screw up life analysis for it. */
4915 if (nominal_mode == passed_mode
4918 && GET_CODE (stack_parm) == MEM
4919 && stack_offset.var == 0
4920 && reg_mentioned_p (virtual_incoming_args_rtx,
4921 XEXP (stack_parm, 0)))
4923 rtx linsn = get_last_insn ();
4926 /* Mark complex types separately. */
4927 if (GET_CODE (parmreg) == CONCAT)
4928 /* Scan backwards for the set of the real and
4930 for (sinsn = linsn; sinsn != 0;
4931 sinsn = prev_nonnote_insn (sinsn))
4933 set = single_set (sinsn);
4935 && SET_DEST (set) == regno_reg_rtx [regnoi])
4937 = gen_rtx_EXPR_LIST (REG_EQUIV,
4938 parm_reg_stack_loc[regnoi],
4941 && SET_DEST (set) == regno_reg_rtx [regnor])
4943 = gen_rtx_EXPR_LIST (REG_EQUIV,
4944 parm_reg_stack_loc[regnor],
4947 else if ((set = single_set (linsn)) != 0
4948 && SET_DEST (set) == parmreg)
4950 = gen_rtx_EXPR_LIST (REG_EQUIV,
4951 stack_parm, REG_NOTES (linsn));
4954 /* For pointer data type, suggest pointer register. */
4955 if (POINTER_TYPE_P (TREE_TYPE (parm)))
4956 mark_reg_pointer (parmreg,
4957 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
4959 /* If something wants our address, try to use ADDRESSOF. */
4960 if (TREE_ADDRESSABLE (parm))
4962 /* If we end up putting something into the stack,
4963 fixup_var_refs_insns will need to make a pass over
4964 all the instructions. It looks throughs the pending
4965 sequences -- but it can't see the ones in the
4966 CONVERSION_INSNS, if they're not on the sequence
4967 stack. So, we go back to that sequence, just so that
4968 the fixups will happen. */
4969 push_to_sequence (conversion_insns);
4970 put_var_into_stack (parm);
4971 conversion_insns = get_insns ();
4977 /* Value must be stored in the stack slot STACK_PARM
4978 during function execution. */
4980 if (promoted_mode != nominal_mode)
4982 /* Conversion is required. */
4983 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4985 emit_move_insn (tempreg, validize_mem (entry_parm));
4987 push_to_sequence (conversion_insns);
4988 entry_parm = convert_to_mode (nominal_mode, tempreg,
4989 TREE_UNSIGNED (TREE_TYPE (parm)));
4992 /* ??? This may need a big-endian conversion on sparc64. */
4993 stack_parm = change_address (stack_parm, nominal_mode,
4996 conversion_insns = get_insns ();
5001 if (entry_parm != stack_parm)
5003 if (stack_parm == 0)
5006 = assign_stack_local (GET_MODE (entry_parm),
5007 GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
5008 set_mem_attributes (stack_parm, parm, 1);
5011 if (promoted_mode != nominal_mode)
5013 push_to_sequence (conversion_insns);
5014 emit_move_insn (validize_mem (stack_parm),
5015 validize_mem (entry_parm));
5016 conversion_insns = get_insns ();
5020 emit_move_insn (validize_mem (stack_parm),
5021 validize_mem (entry_parm));
5023 if (current_function_check_memory_usage)
5025 push_to_sequence (conversion_insns);
5026 emit_library_call (chkr_set_right_libfunc, LCT_CONST_MAKE_BLOCK,
5027 VOIDmode, 3, XEXP (stack_parm, 0), Pmode,
5028 GEN_INT (GET_MODE_SIZE (GET_MODE
5030 TYPE_MODE (sizetype),
5031 GEN_INT (MEMORY_USE_RW),
5032 TYPE_MODE (integer_type_node));
5034 conversion_insns = get_insns ();
5037 SET_DECL_RTL (parm, stack_parm);
5040 /* If this "parameter" was the place where we are receiving the
5041 function's incoming structure pointer, set up the result. */
5042 if (parm == function_result_decl)
5044 tree result = DECL_RESULT (fndecl);
5046 SET_DECL_RTL (result,
5047 gen_rtx_MEM (DECL_MODE (result), DECL_RTL (parm)));
5049 set_mem_attributes (DECL_RTL (result), result, 1);
5053 /* Output all parameter conversion instructions (possibly including calls)
5054 now that all parameters have been copied out of hard registers. */
5055 emit_insns (conversion_insns);
5057 last_parm_insn = get_last_insn ();
5059 current_function_args_size = stack_args_size.constant;
5061 /* Adjust function incoming argument size for alignment and
5064 #ifdef REG_PARM_STACK_SPACE
5065 #ifndef MAYBE_REG_PARM_STACK_SPACE
5066 current_function_args_size = MAX (current_function_args_size,
5067 REG_PARM_STACK_SPACE (fndecl));
5071 #ifdef STACK_BOUNDARY
5072 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
5074 current_function_args_size
5075 = ((current_function_args_size + STACK_BYTES - 1)
5076 / STACK_BYTES) * STACK_BYTES;
5079 #ifdef ARGS_GROW_DOWNWARD
5080 current_function_arg_offset_rtx
5081 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
5082 : expand_expr (size_diffop (stack_args_size.var,
5083 size_int (-stack_args_size.constant)),
5084 NULL_RTX, VOIDmode, EXPAND_MEMORY_USE_BAD));
5086 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
5089 /* See how many bytes, if any, of its args a function should try to pop
5092 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
5093 current_function_args_size);
5095 /* For stdarg.h function, save info about
5096 regs and stack space used by the named args. */
5099 current_function_args_info = args_so_far;
5101 /* Set the rtx used for the function return value. Put this in its
5102 own variable so any optimizers that need this information don't have
5103 to include tree.h. Do this here so it gets done when an inlined
5104 function gets output. */
5106 current_function_return_rtx
5107 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
5108 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
5111 /* Indicate whether REGNO is an incoming argument to the current function
5112 that was promoted to a wider mode. If so, return the RTX for the
5113 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5114 that REGNO is promoted from and whether the promotion was signed or
5117 #ifdef PROMOTE_FUNCTION_ARGS
5120 promoted_input_arg (regno, pmode, punsignedp)
5122 enum machine_mode *pmode;
5127 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
5128 arg = TREE_CHAIN (arg))
5129 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
5130 && REGNO (DECL_INCOMING_RTL (arg)) == regno
5131 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
5133 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
5134 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
5136 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
5137 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
5138 && mode != DECL_MODE (arg))
5140 *pmode = DECL_MODE (arg);
5141 *punsignedp = unsignedp;
5142 return DECL_INCOMING_RTL (arg);
5151 /* Compute the size and offset from the start of the stacked arguments for a
5152 parm passed in mode PASSED_MODE and with type TYPE.
5154 INITIAL_OFFSET_PTR points to the current offset into the stacked
5157 The starting offset and size for this parm are returned in *OFFSET_PTR
5158 and *ARG_SIZE_PTR, respectively.
5160 IN_REGS is non-zero if the argument will be passed in registers. It will
5161 never be set if REG_PARM_STACK_SPACE is not defined.
5163 FNDECL is the function in which the argument was defined.
5165 There are two types of rounding that are done. The first, controlled by
5166 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5167 list to be aligned to the specific boundary (in bits). This rounding
5168 affects the initial and starting offsets, but not the argument size.
5170 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5171 optionally rounds the size of the parm to PARM_BOUNDARY. The
5172 initial offset is not affected by this rounding, while the size always
5173 is and the starting offset may be. */
5175 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
5176 initial_offset_ptr is positive because locate_and_pad_parm's
5177 callers pass in the total size of args so far as
5178 initial_offset_ptr. arg_size_ptr is always positive.*/
5181 locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
5182 initial_offset_ptr, offset_ptr, arg_size_ptr,
5184 enum machine_mode passed_mode;
5186 int in_regs ATTRIBUTE_UNUSED;
5187 tree fndecl ATTRIBUTE_UNUSED;
5188 struct args_size *initial_offset_ptr;
5189 struct args_size *offset_ptr;
5190 struct args_size *arg_size_ptr;
5191 struct args_size *alignment_pad;
5195 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5196 enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5197 int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5199 #ifdef REG_PARM_STACK_SPACE
5200 /* If we have found a stack parm before we reach the end of the
5201 area reserved for registers, skip that area. */
5204 int reg_parm_stack_space = 0;
5206 #ifdef MAYBE_REG_PARM_STACK_SPACE
5207 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
5209 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5211 if (reg_parm_stack_space > 0)
5213 if (initial_offset_ptr->var)
5215 initial_offset_ptr->var
5216 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5217 ssize_int (reg_parm_stack_space));
5218 initial_offset_ptr->constant = 0;
5220 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5221 initial_offset_ptr->constant = reg_parm_stack_space;
5224 #endif /* REG_PARM_STACK_SPACE */
5226 arg_size_ptr->var = 0;
5227 arg_size_ptr->constant = 0;
5228 alignment_pad->var = 0;
5229 alignment_pad->constant = 0;
5231 #ifdef ARGS_GROW_DOWNWARD
5232 if (initial_offset_ptr->var)
5234 offset_ptr->constant = 0;
5235 offset_ptr->var = size_binop (MINUS_EXPR, ssize_int (0),
5236 initial_offset_ptr->var);
5240 offset_ptr->constant = -initial_offset_ptr->constant;
5241 offset_ptr->var = 0;
5243 if (where_pad != none
5244 && (!host_integerp (sizetree, 1)
5245 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5246 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5247 SUB_PARM_SIZE (*offset_ptr, sizetree);
5248 if (where_pad != downward)
5249 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad);
5250 if (initial_offset_ptr->var)
5251 arg_size_ptr->var = size_binop (MINUS_EXPR,
5252 size_binop (MINUS_EXPR,
5254 initial_offset_ptr->var),
5258 arg_size_ptr->constant = (-initial_offset_ptr->constant
5259 - offset_ptr->constant);
5261 #else /* !ARGS_GROW_DOWNWARD */
5263 #ifdef REG_PARM_STACK_SPACE
5264 || REG_PARM_STACK_SPACE (fndecl) > 0
5267 pad_to_arg_alignment (initial_offset_ptr, boundary, alignment_pad);
5268 *offset_ptr = *initial_offset_ptr;
5270 #ifdef PUSH_ROUNDING
5271 if (passed_mode != BLKmode)
5272 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5275 /* Pad_below needs the pre-rounded size to know how much to pad below
5276 so this must be done before rounding up. */
5277 if (where_pad == downward
5278 /* However, BLKmode args passed in regs have their padding done elsewhere.
5279 The stack slot must be able to hold the entire register. */
5280 && !(in_regs && passed_mode == BLKmode))
5281 pad_below (offset_ptr, passed_mode, sizetree);
5283 if (where_pad != none
5284 && (!host_integerp (sizetree, 1)
5285 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5286 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5288 ADD_PARM_SIZE (*arg_size_ptr, sizetree);
5289 #endif /* ARGS_GROW_DOWNWARD */
5292 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5293 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5296 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad)
5297 struct args_size *offset_ptr;
5299 struct args_size *alignment_pad;
5301 tree save_var = NULL_TREE;
5302 HOST_WIDE_INT save_constant = 0;
5304 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5306 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5308 save_var = offset_ptr->var;
5309 save_constant = offset_ptr->constant;
5312 alignment_pad->var = NULL_TREE;
5313 alignment_pad->constant = 0;
5315 if (boundary > BITS_PER_UNIT)
5317 if (offset_ptr->var)
5320 #ifdef ARGS_GROW_DOWNWARD
5325 (ARGS_SIZE_TREE (*offset_ptr),
5326 boundary / BITS_PER_UNIT);
5327 offset_ptr->constant = 0; /*?*/
5328 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5329 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5334 offset_ptr->constant =
5335 #ifdef ARGS_GROW_DOWNWARD
5336 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
5338 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
5340 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5341 alignment_pad->constant = offset_ptr->constant - save_constant;
5346 #ifndef ARGS_GROW_DOWNWARD
5348 pad_below (offset_ptr, passed_mode, sizetree)
5349 struct args_size *offset_ptr;
5350 enum machine_mode passed_mode;
5353 if (passed_mode != BLKmode)
5355 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5356 offset_ptr->constant
5357 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5358 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5359 - GET_MODE_SIZE (passed_mode));
5363 if (TREE_CODE (sizetree) != INTEGER_CST
5364 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5366 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5367 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5369 ADD_PARM_SIZE (*offset_ptr, s2);
5370 SUB_PARM_SIZE (*offset_ptr, sizetree);
5376 /* Walk the tree of blocks describing the binding levels within a function
5377 and warn about uninitialized variables.
5378 This is done after calling flow_analysis and before global_alloc
5379 clobbers the pseudo-regs to hard regs. */
5382 uninitialized_vars_warning (block)
5385 register tree decl, sub;
5386 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5388 if (warn_uninitialized
5389 && TREE_CODE (decl) == VAR_DECL
5390 /* These warnings are unreliable for and aggregates
5391 because assigning the fields one by one can fail to convince
5392 flow.c that the entire aggregate was initialized.
5393 Unions are troublesome because members may be shorter. */
5394 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5395 && DECL_RTL (decl) != 0
5396 && GET_CODE (DECL_RTL (decl)) == REG
5397 /* Global optimizations can make it difficult to determine if a
5398 particular variable has been initialized. However, a VAR_DECL
5399 with a nonzero DECL_INITIAL had an initializer, so do not
5400 claim it is potentially uninitialized.
5402 We do not care about the actual value in DECL_INITIAL, so we do
5403 not worry that it may be a dangling pointer. */
5404 && DECL_INITIAL (decl) == NULL_TREE
5405 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5406 warning_with_decl (decl,
5407 "`%s' might be used uninitialized in this function");
5409 && TREE_CODE (decl) == VAR_DECL
5410 && DECL_RTL (decl) != 0
5411 && GET_CODE (DECL_RTL (decl)) == REG
5412 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5413 warning_with_decl (decl,
5414 "variable `%s' might be clobbered by `longjmp' or `vfork'");
5416 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5417 uninitialized_vars_warning (sub);
5420 /* Do the appropriate part of uninitialized_vars_warning
5421 but for arguments instead of local variables. */
5424 setjmp_args_warning ()
5427 for (decl = DECL_ARGUMENTS (current_function_decl);
5428 decl; decl = TREE_CHAIN (decl))
5429 if (DECL_RTL (decl) != 0
5430 && GET_CODE (DECL_RTL (decl)) == REG
5431 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5432 warning_with_decl (decl,
5433 "argument `%s' might be clobbered by `longjmp' or `vfork'");
5436 /* If this function call setjmp, put all vars into the stack
5437 unless they were declared `register'. */
5440 setjmp_protect (block)
5443 register tree decl, sub;
5444 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5445 if ((TREE_CODE (decl) == VAR_DECL
5446 || TREE_CODE (decl) == PARM_DECL)
5447 && DECL_RTL (decl) != 0
5448 && (GET_CODE (DECL_RTL (decl)) == REG
5449 || (GET_CODE (DECL_RTL (decl)) == MEM
5450 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5451 /* If this variable came from an inline function, it must be
5452 that its life doesn't overlap the setjmp. If there was a
5453 setjmp in the function, it would already be in memory. We
5454 must exclude such variable because their DECL_RTL might be
5455 set to strange things such as virtual_stack_vars_rtx. */
5456 && ! DECL_FROM_INLINE (decl)
5458 #ifdef NON_SAVING_SETJMP
5459 /* If longjmp doesn't restore the registers,
5460 don't put anything in them. */
5464 ! DECL_REGISTER (decl)))
5465 put_var_into_stack (decl);
5466 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5467 setjmp_protect (sub);
5470 /* Like the previous function, but for args instead of local variables. */
5473 setjmp_protect_args ()
5476 for (decl = DECL_ARGUMENTS (current_function_decl);
5477 decl; decl = TREE_CHAIN (decl))
5478 if ((TREE_CODE (decl) == VAR_DECL
5479 || TREE_CODE (decl) == PARM_DECL)
5480 && DECL_RTL (decl) != 0
5481 && (GET_CODE (DECL_RTL (decl)) == REG
5482 || (GET_CODE (DECL_RTL (decl)) == MEM
5483 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5485 /* If longjmp doesn't restore the registers,
5486 don't put anything in them. */
5487 #ifdef NON_SAVING_SETJMP
5491 ! DECL_REGISTER (decl)))
5492 put_var_into_stack (decl);
5495 /* Return the context-pointer register corresponding to DECL,
5496 or 0 if it does not need one. */
5499 lookup_static_chain (decl)
5502 tree context = decl_function_context (decl);
5506 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5509 /* We treat inline_function_decl as an alias for the current function
5510 because that is the inline function whose vars, types, etc.
5511 are being merged into the current function.
5512 See expand_inline_function. */
5513 if (context == current_function_decl || context == inline_function_decl)
5514 return virtual_stack_vars_rtx;
5516 for (link = context_display; link; link = TREE_CHAIN (link))
5517 if (TREE_PURPOSE (link) == context)
5518 return RTL_EXPR_RTL (TREE_VALUE (link));
5523 /* Convert a stack slot address ADDR for variable VAR
5524 (from a containing function)
5525 into an address valid in this function (using a static chain). */
5528 fix_lexical_addr (addr, var)
5533 HOST_WIDE_INT displacement;
5534 tree context = decl_function_context (var);
5535 struct function *fp;
5538 /* If this is the present function, we need not do anything. */
5539 if (context == current_function_decl || context == inline_function_decl)
5542 for (fp = outer_function_chain; fp; fp = fp->next)
5543 if (fp->decl == context)
5549 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5550 addr = XEXP (XEXP (addr, 0), 0);
5552 /* Decode given address as base reg plus displacement. */
5553 if (GET_CODE (addr) == REG)
5554 basereg = addr, displacement = 0;
5555 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5556 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5560 /* We accept vars reached via the containing function's
5561 incoming arg pointer and via its stack variables pointer. */
5562 if (basereg == fp->internal_arg_pointer)
5564 /* If reached via arg pointer, get the arg pointer value
5565 out of that function's stack frame.
5567 There are two cases: If a separate ap is needed, allocate a
5568 slot in the outer function for it and dereference it that way.
5569 This is correct even if the real ap is actually a pseudo.
5570 Otherwise, just adjust the offset from the frame pointer to
5573 #ifdef NEED_SEPARATE_AP
5576 if (fp->x_arg_pointer_save_area == 0)
5577 fp->x_arg_pointer_save_area
5578 = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, fp);
5580 addr = fix_lexical_addr (XEXP (fp->x_arg_pointer_save_area, 0), var);
5581 addr = memory_address (Pmode, addr);
5583 base = gen_rtx_MEM (Pmode, addr);
5584 MEM_ALIAS_SET (base) = get_frame_alias_set ();
5585 base = copy_to_reg (base);
5587 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5588 base = lookup_static_chain (var);
5592 else if (basereg == virtual_stack_vars_rtx)
5594 /* This is the same code as lookup_static_chain, duplicated here to
5595 avoid an extra call to decl_function_context. */
5598 for (link = context_display; link; link = TREE_CHAIN (link))
5599 if (TREE_PURPOSE (link) == context)
5601 base = RTL_EXPR_RTL (TREE_VALUE (link));
5609 /* Use same offset, relative to appropriate static chain or argument
5611 return plus_constant (base, displacement);
5614 /* Return the address of the trampoline for entering nested fn FUNCTION.
5615 If necessary, allocate a trampoline (in the stack frame)
5616 and emit rtl to initialize its contents (at entry to this function). */
5619 trampoline_address (function)
5625 struct function *fp;
5628 /* Find an existing trampoline and return it. */
5629 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5630 if (TREE_PURPOSE (link) == function)
5632 adjust_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5634 for (fp = outer_function_chain; fp; fp = fp->next)
5635 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5636 if (TREE_PURPOSE (link) == function)
5638 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5640 return adjust_trampoline_addr (tramp);
5643 /* None exists; we must make one. */
5645 /* Find the `struct function' for the function containing FUNCTION. */
5647 fn_context = decl_function_context (function);
5648 if (fn_context != current_function_decl
5649 && fn_context != inline_function_decl)
5650 for (fp = outer_function_chain; fp; fp = fp->next)
5651 if (fp->decl == fn_context)
5654 /* Allocate run-time space for this trampoline
5655 (usually in the defining function's stack frame). */
5656 #ifdef ALLOCATE_TRAMPOLINE
5657 tramp = ALLOCATE_TRAMPOLINE (fp);
5659 /* If rounding needed, allocate extra space
5660 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5661 #ifdef TRAMPOLINE_ALIGNMENT
5662 #define TRAMPOLINE_REAL_SIZE \
5663 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5665 #define TRAMPOLINE_REAL_SIZE (TRAMPOLINE_SIZE)
5667 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5671 /* Record the trampoline for reuse and note it for later initialization
5672 by expand_function_end. */
5675 rtlexp = make_node (RTL_EXPR);
5676 RTL_EXPR_RTL (rtlexp) = tramp;
5677 fp->x_trampoline_list = tree_cons (function, rtlexp,
5678 fp->x_trampoline_list);
5682 /* Make the RTL_EXPR node temporary, not momentary, so that the
5683 trampoline_list doesn't become garbage. */
5684 rtlexp = make_node (RTL_EXPR);
5686 RTL_EXPR_RTL (rtlexp) = tramp;
5687 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5690 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5691 return adjust_trampoline_addr (tramp);
5694 /* Given a trampoline address,
5695 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5698 round_trampoline_addr (tramp)
5701 #ifdef TRAMPOLINE_ALIGNMENT
5702 /* Round address up to desired boundary. */
5703 rtx temp = gen_reg_rtx (Pmode);
5704 temp = expand_binop (Pmode, add_optab, tramp,
5705 GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1),
5706 temp, 0, OPTAB_LIB_WIDEN);
5707 tramp = expand_binop (Pmode, and_optab, temp,
5708 GEN_INT (-TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT),
5709 temp, 0, OPTAB_LIB_WIDEN);
5714 /* Given a trampoline address, round it then apply any
5715 platform-specific adjustments so that the result can be used for a
5719 adjust_trampoline_addr (tramp)
5722 tramp = round_trampoline_addr (tramp);
5723 #ifdef TRAMPOLINE_ADJUST_ADDRESS
5724 TRAMPOLINE_ADJUST_ADDRESS (tramp);
5729 /* Put all this function's BLOCK nodes including those that are chained
5730 onto the first block into a vector, and return it.
5731 Also store in each NOTE for the beginning or end of a block
5732 the index of that block in the vector.
5733 The arguments are BLOCK, the chain of top-level blocks of the function,
5734 and INSNS, the insn chain of the function. */
5740 tree *block_vector, *last_block_vector;
5742 tree block = DECL_INITIAL (current_function_decl);
5747 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5748 depth-first order. */
5749 block_vector = get_block_vector (block, &n_blocks);
5750 block_stack = (tree *) xmalloc (n_blocks * sizeof (tree));
5752 last_block_vector = identify_blocks_1 (get_insns (),
5754 block_vector + n_blocks,
5757 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5758 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5759 if (0 && last_block_vector != block_vector + n_blocks)
5762 free (block_vector);
5766 /* Subroutine of identify_blocks. Do the block substitution on the
5767 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
5769 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5770 BLOCK_VECTOR is incremented for each block seen. */
5773 identify_blocks_1 (insns, block_vector, end_block_vector, orig_block_stack)
5776 tree *end_block_vector;
5777 tree *orig_block_stack;
5780 tree *block_stack = orig_block_stack;
5782 for (insn = insns; insn; insn = NEXT_INSN (insn))
5784 if (GET_CODE (insn) == NOTE)
5786 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5790 /* If there are more block notes than BLOCKs, something
5792 if (block_vector == end_block_vector)
5795 b = *block_vector++;
5796 NOTE_BLOCK (insn) = b;
5799 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5801 /* If there are more NOTE_INSN_BLOCK_ENDs than
5802 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
5803 if (block_stack == orig_block_stack)
5806 NOTE_BLOCK (insn) = *--block_stack;
5809 else if (GET_CODE (insn) == CALL_INSN
5810 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5812 rtx cp = PATTERN (insn);
5814 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
5815 end_block_vector, block_stack);
5817 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
5818 end_block_vector, block_stack);
5820 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
5821 end_block_vector, block_stack);
5825 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
5826 something is badly wrong. */
5827 if (block_stack != orig_block_stack)
5830 return block_vector;
5833 /* Identify BLOCKs referenced by more than one
5834 NOTE_INSN_BLOCK_{BEG,END}, and create duplicate blocks. */
5839 tree block = DECL_INITIAL (current_function_decl);
5840 varray_type block_stack;
5842 if (block == NULL_TREE)
5845 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
5847 /* Prune the old trees away, so that they don't get in the way. */
5848 BLOCK_SUBBLOCKS (block) = NULL_TREE;
5849 BLOCK_CHAIN (block) = NULL_TREE;
5851 reorder_blocks_0 (get_insns ());
5852 reorder_blocks_1 (get_insns (), block, &block_stack);
5854 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
5856 VARRAY_FREE (block_stack);
5859 /* Helper function for reorder_blocks. Process the insn chain beginning
5860 at INSNS. Recurse for CALL_PLACEHOLDER insns. */
5863 reorder_blocks_0 (insns)
5868 for (insn = insns; insn; insn = NEXT_INSN (insn))
5870 if (GET_CODE (insn) == NOTE)
5872 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5874 tree block = NOTE_BLOCK (insn);
5875 TREE_ASM_WRITTEN (block) = 0;
5878 else if (GET_CODE (insn) == CALL_INSN
5879 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5881 rtx cp = PATTERN (insn);
5882 reorder_blocks_0 (XEXP (cp, 0));
5884 reorder_blocks_0 (XEXP (cp, 1));
5886 reorder_blocks_0 (XEXP (cp, 2));
5892 reorder_blocks_1 (insns, current_block, p_block_stack)
5895 varray_type *p_block_stack;
5899 for (insn = insns; insn; insn = NEXT_INSN (insn))
5901 if (GET_CODE (insn) == NOTE)
5903 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5905 tree block = NOTE_BLOCK (insn);
5906 /* If we have seen this block before, copy it. */
5907 if (TREE_ASM_WRITTEN (block))
5909 block = copy_node (block);
5910 NOTE_BLOCK (insn) = block;
5912 BLOCK_SUBBLOCKS (block) = 0;
5913 TREE_ASM_WRITTEN (block) = 1;
5914 BLOCK_SUPERCONTEXT (block) = current_block;
5915 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
5916 BLOCK_SUBBLOCKS (current_block) = block;
5917 current_block = block;
5918 VARRAY_PUSH_TREE (*p_block_stack, block);
5920 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5922 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
5923 VARRAY_POP (*p_block_stack);
5924 BLOCK_SUBBLOCKS (current_block)
5925 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5926 current_block = BLOCK_SUPERCONTEXT (current_block);
5929 else if (GET_CODE (insn) == CALL_INSN
5930 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5932 rtx cp = PATTERN (insn);
5933 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
5935 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
5937 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
5942 /* Reverse the order of elements in the chain T of blocks,
5943 and return the new head of the chain (old last element). */
5949 register tree prev = 0, decl, next;
5950 for (decl = t; decl; decl = next)
5952 next = BLOCK_CHAIN (decl);
5953 BLOCK_CHAIN (decl) = prev;
5959 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
5960 non-NULL, list them all into VECTOR, in a depth-first preorder
5961 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
5965 all_blocks (block, vector)
5973 TREE_ASM_WRITTEN (block) = 0;
5975 /* Record this block. */
5977 vector[n_blocks] = block;
5981 /* Record the subblocks, and their subblocks... */
5982 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
5983 vector ? vector + n_blocks : 0);
5984 block = BLOCK_CHAIN (block);
5990 /* Return a vector containing all the blocks rooted at BLOCK. The
5991 number of elements in the vector is stored in N_BLOCKS_P. The
5992 vector is dynamically allocated; it is the caller's responsibility
5993 to call `free' on the pointer returned. */
5996 get_block_vector (block, n_blocks_p)
6002 *n_blocks_p = all_blocks (block, NULL);
6003 block_vector = (tree *) xmalloc (*n_blocks_p * sizeof (tree));
6004 all_blocks (block, block_vector);
6006 return block_vector;
6009 static int next_block_index = 2;
6011 /* Set BLOCK_NUMBER for all the blocks in FN. */
6021 /* For SDB and XCOFF debugging output, we start numbering the blocks
6022 from 1 within each function, rather than keeping a running
6024 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6025 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
6026 next_block_index = 1;
6029 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
6031 /* The top-level BLOCK isn't numbered at all. */
6032 for (i = 1; i < n_blocks; ++i)
6033 /* We number the blocks from two. */
6034 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
6036 free (block_vector);
6041 /* Allocate a function structure and reset its contents to the defaults. */
6043 prepare_function_start ()
6045 cfun = (struct function *) xcalloc (1, sizeof (struct function));
6047 init_stmt_for_function ();
6048 init_eh_for_function ();
6050 cse_not_expected = ! optimize;
6052 /* Caller save not needed yet. */
6053 caller_save_needed = 0;
6055 /* No stack slots have been made yet. */
6056 stack_slot_list = 0;
6058 current_function_has_nonlocal_label = 0;
6059 current_function_has_nonlocal_goto = 0;
6061 /* There is no stack slot for handling nonlocal gotos. */
6062 nonlocal_goto_handler_slots = 0;
6063 nonlocal_goto_stack_level = 0;
6065 /* No labels have been declared for nonlocal use. */
6066 nonlocal_labels = 0;
6067 nonlocal_goto_handler_labels = 0;
6069 /* No function calls so far in this function. */
6070 function_call_count = 0;
6072 /* No parm regs have been allocated.
6073 (This is important for output_inline_function.) */
6074 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
6076 /* Initialize the RTL mechanism. */
6079 /* Initialize the queue of pending postincrement and postdecrements,
6080 and some other info in expr.c. */
6083 /* We haven't done register allocation yet. */
6086 init_varasm_status (cfun);
6088 /* Clear out data used for inlining. */
6089 cfun->inlinable = 0;
6090 cfun->original_decl_initial = 0;
6091 cfun->original_arg_vector = 0;
6093 #ifdef STACK_BOUNDARY
6094 cfun->stack_alignment_needed = STACK_BOUNDARY;
6095 cfun->preferred_stack_boundary = STACK_BOUNDARY;
6097 cfun->stack_alignment_needed = 0;
6098 cfun->preferred_stack_boundary = 0;
6101 /* Set if a call to setjmp is seen. */
6102 current_function_calls_setjmp = 0;
6104 /* Set if a call to longjmp is seen. */
6105 current_function_calls_longjmp = 0;
6107 current_function_calls_alloca = 0;
6108 current_function_contains_functions = 0;
6109 current_function_is_leaf = 0;
6110 current_function_nothrow = 0;
6111 current_function_sp_is_unchanging = 0;
6112 current_function_uses_only_leaf_regs = 0;
6113 current_function_has_computed_jump = 0;
6114 current_function_is_thunk = 0;
6116 current_function_returns_pcc_struct = 0;
6117 current_function_returns_struct = 0;
6118 current_function_epilogue_delay_list = 0;
6119 current_function_uses_const_pool = 0;
6120 current_function_uses_pic_offset_table = 0;
6121 current_function_cannot_inline = 0;
6123 /* We have not yet needed to make a label to jump to for tail-recursion. */
6124 tail_recursion_label = 0;
6126 /* We haven't had a need to make a save area for ap yet. */
6127 arg_pointer_save_area = 0;
6129 /* No stack slots allocated yet. */
6132 /* No SAVE_EXPRs in this function yet. */
6135 /* No RTL_EXPRs in this function yet. */
6138 /* Set up to allocate temporaries. */
6141 /* Indicate that we need to distinguish between the return value of the
6142 present function and the return value of a function being called. */
6143 rtx_equal_function_value_matters = 1;
6145 /* Indicate that we have not instantiated virtual registers yet. */
6146 virtuals_instantiated = 0;
6148 /* Indicate that we want CONCATs now. */
6149 generating_concat_p = 1;
6151 /* Indicate we have no need of a frame pointer yet. */
6152 frame_pointer_needed = 0;
6154 /* By default assume not varargs or stdarg. */
6155 current_function_varargs = 0;
6156 current_function_stdarg = 0;
6158 /* We haven't made any trampolines for this function yet. */
6159 trampoline_list = 0;
6161 init_pending_stack_adjust ();
6162 inhibit_defer_pop = 0;
6164 current_function_outgoing_args_size = 0;
6166 if (init_lang_status)
6167 (*init_lang_status) (cfun);
6168 if (init_machine_status)
6169 (*init_machine_status) (cfun);
6172 /* Initialize the rtl expansion mechanism so that we can do simple things
6173 like generate sequences. This is used to provide a context during global
6174 initialization of some passes. */
6176 init_dummy_function_start ()
6178 prepare_function_start ();
6181 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6182 and initialize static variables for generating RTL for the statements
6186 init_function_start (subr, filename, line)
6188 const char *filename;
6191 prepare_function_start ();
6193 /* Remember this function for later. */
6194 cfun->next_global = all_functions;
6195 all_functions = cfun;
6197 current_function_name = (*decl_printable_name) (subr, 2);
6200 /* Nonzero if this is a nested function that uses a static chain. */
6202 current_function_needs_context
6203 = (decl_function_context (current_function_decl) != 0
6204 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
6206 /* Within function body, compute a type's size as soon it is laid out. */
6207 immediate_size_expand++;
6209 /* Prevent ever trying to delete the first instruction of a function.
6210 Also tell final how to output a linenum before the function prologue.
6211 Note linenums could be missing, e.g. when compiling a Java .class file. */
6213 emit_line_note (filename, line);
6215 /* Make sure first insn is a note even if we don't want linenums.
6216 This makes sure the first insn will never be deleted.
6217 Also, final expects a note to appear there. */
6218 emit_note (NULL_PTR, NOTE_INSN_DELETED);
6220 /* Set flags used by final.c. */
6221 if (aggregate_value_p (DECL_RESULT (subr)))
6223 #ifdef PCC_STATIC_STRUCT_RETURN
6224 current_function_returns_pcc_struct = 1;
6226 current_function_returns_struct = 1;
6229 /* Warn if this value is an aggregate type,
6230 regardless of which calling convention we are using for it. */
6231 if (warn_aggregate_return
6232 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6233 warning ("function returns an aggregate");
6235 current_function_returns_pointer
6236 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
6239 /* Make sure all values used by the optimization passes have sane
6242 init_function_for_compilation ()
6246 /* No prologue/epilogue insns yet. */
6247 VARRAY_GROW (prologue, 0);
6248 VARRAY_GROW (epilogue, 0);
6249 VARRAY_GROW (sibcall_epilogue, 0);
6252 /* Indicate that the current function uses extra args
6253 not explicitly mentioned in the argument list in any fashion. */
6258 current_function_varargs = 1;
6261 /* Expand a call to __main at the beginning of a possible main function. */
6263 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6264 #undef HAS_INIT_SECTION
6265 #define HAS_INIT_SECTION
6269 expand_main_function ()
6271 #if !defined (HAS_INIT_SECTION)
6272 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, NAME__MAIN), 0,
6274 #endif /* not HAS_INIT_SECTION */
6277 extern struct obstack permanent_obstack;
6279 /* Start the RTL for a new function, and set variables used for
6281 SUBR is the FUNCTION_DECL node.
6282 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6283 the function's parameters, which must be run at any return statement. */
6286 expand_function_start (subr, parms_have_cleanups)
6288 int parms_have_cleanups;
6291 rtx last_ptr = NULL_RTX;
6293 /* Make sure volatile mem refs aren't considered
6294 valid operands of arithmetic insns. */
6295 init_recog_no_volatile ();
6297 /* Set this before generating any memory accesses. */
6298 current_function_check_memory_usage
6299 = (flag_check_memory_usage
6300 && ! DECL_NO_CHECK_MEMORY_USAGE (current_function_decl));
6302 current_function_instrument_entry_exit
6303 = (flag_instrument_function_entry_exit
6304 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6306 current_function_limit_stack
6307 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6309 /* If function gets a static chain arg, store it in the stack frame.
6310 Do this first, so it gets the first stack slot offset. */
6311 if (current_function_needs_context)
6313 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
6315 /* Delay copying static chain if it is not a register to avoid
6316 conflicts with regs used for parameters. */
6317 if (! SMALL_REGISTER_CLASSES
6318 || GET_CODE (static_chain_incoming_rtx) == REG)
6319 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6322 /* If the parameters of this function need cleaning up, get a label
6323 for the beginning of the code which executes those cleanups. This must
6324 be done before doing anything with return_label. */
6325 if (parms_have_cleanups)
6326 cleanup_label = gen_label_rtx ();
6330 /* Make the label for return statements to jump to. Do not special
6331 case machines with special return instructions -- they will be
6332 handled later during jump, ifcvt, or epilogue creation. */
6333 return_label = gen_label_rtx ();
6335 /* Initialize rtx used to return the value. */
6336 /* Do this before assign_parms so that we copy the struct value address
6337 before any library calls that assign parms might generate. */
6339 /* Decide whether to return the value in memory or in a register. */
6340 if (aggregate_value_p (DECL_RESULT (subr)))
6342 /* Returning something that won't go in a register. */
6343 register rtx value_address = 0;
6345 #ifdef PCC_STATIC_STRUCT_RETURN
6346 if (current_function_returns_pcc_struct)
6348 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6349 value_address = assemble_static_space (size);
6354 /* Expect to be passed the address of a place to store the value.
6355 If it is passed as an argument, assign_parms will take care of
6357 if (struct_value_incoming_rtx)
6359 value_address = gen_reg_rtx (Pmode);
6360 emit_move_insn (value_address, struct_value_incoming_rtx);
6365 SET_DECL_RTL (DECL_RESULT (subr),
6366 gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)),
6368 set_mem_attributes (DECL_RTL (DECL_RESULT (subr)),
6369 DECL_RESULT (subr), 1);
6372 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6373 /* If return mode is void, this decl rtl should not be used. */
6374 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
6375 else if (parms_have_cleanups
6376 || current_function_instrument_entry_exit
6377 || (flag_exceptions && USING_SJLJ_EXCEPTIONS))
6379 /* If function will end with cleanup code for parms,
6380 compute the return values into a pseudo reg,
6381 which we will copy into the true return register
6382 after the cleanups are done. */
6384 enum machine_mode mode = DECL_MODE (DECL_RESULT (subr));
6386 #ifdef PROMOTE_FUNCTION_RETURN
6387 tree type = TREE_TYPE (DECL_RESULT (subr));
6388 int unsignedp = TREE_UNSIGNED (type);
6390 mode = promote_mode (type, mode, &unsignedp, 1);
6393 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (mode));
6394 /* Needed because we may need to move this to memory
6395 in case it's a named return value whose address is taken. */
6396 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6400 /* Scalar, returned in a register. */
6401 SET_DECL_RTL (DECL_RESULT (subr),
6402 hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
6405 /* Mark this reg as the function's return value. */
6406 if (GET_CODE (DECL_RTL (DECL_RESULT (subr))) == REG)
6408 REG_FUNCTION_VALUE_P (DECL_RTL (DECL_RESULT (subr))) = 1;
6409 /* Needed because we may need to move this to memory
6410 in case it's a named return value whose address is taken. */
6411 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6415 /* Initialize rtx for parameters and local variables.
6416 In some cases this requires emitting insns. */
6418 assign_parms (subr);
6420 /* Copy the static chain now if it wasn't a register. The delay is to
6421 avoid conflicts with the parameter passing registers. */
6423 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6424 if (GET_CODE (static_chain_incoming_rtx) != REG)
6425 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6427 /* The following was moved from init_function_start.
6428 The move is supposed to make sdb output more accurate. */
6429 /* Indicate the beginning of the function body,
6430 as opposed to parm setup. */
6431 emit_note (NULL_PTR, NOTE_INSN_FUNCTION_BEG);
6433 if (GET_CODE (get_last_insn ()) != NOTE)
6434 emit_note (NULL_PTR, NOTE_INSN_DELETED);
6435 parm_birth_insn = get_last_insn ();
6437 context_display = 0;
6438 if (current_function_needs_context)
6440 /* Fetch static chain values for containing functions. */
6441 tem = decl_function_context (current_function_decl);
6442 /* Copy the static chain pointer into a pseudo. If we have
6443 small register classes, copy the value from memory if
6444 static_chain_incoming_rtx is a REG. */
6447 /* If the static chain originally came in a register, put it back
6448 there, then move it out in the next insn. The reason for
6449 this peculiar code is to satisfy function integration. */
6450 if (SMALL_REGISTER_CLASSES
6451 && GET_CODE (static_chain_incoming_rtx) == REG)
6452 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6453 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6458 tree rtlexp = make_node (RTL_EXPR);
6460 RTL_EXPR_RTL (rtlexp) = last_ptr;
6461 context_display = tree_cons (tem, rtlexp, context_display);
6462 tem = decl_function_context (tem);
6465 /* Chain thru stack frames, assuming pointer to next lexical frame
6466 is found at the place we always store it. */
6467 #ifdef FRAME_GROWS_DOWNWARD
6468 last_ptr = plus_constant (last_ptr,
6469 -(HOST_WIDE_INT) GET_MODE_SIZE (Pmode));
6471 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr));
6472 MEM_ALIAS_SET (last_ptr) = get_frame_alias_set ();
6473 last_ptr = copy_to_reg (last_ptr);
6475 /* If we are not optimizing, ensure that we know that this
6476 piece of context is live over the entire function. */
6478 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6483 if (current_function_instrument_entry_exit)
6485 rtx fun = DECL_RTL (current_function_decl);
6486 if (GET_CODE (fun) == MEM)
6487 fun = XEXP (fun, 0);
6490 emit_library_call (profile_function_entry_libfunc, 0, VOIDmode, 2,
6492 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6494 hard_frame_pointer_rtx),
6500 PROFILE_HOOK (profile_label_no);
6503 /* After the display initializations is where the tail-recursion label
6504 should go, if we end up needing one. Ensure we have a NOTE here
6505 since some things (like trampolines) get placed before this. */
6506 tail_recursion_reentry = emit_note (NULL_PTR, NOTE_INSN_DELETED);
6508 /* Evaluate now the sizes of any types declared among the arguments. */
6509 for (tem = nreverse (get_pending_sizes ()); tem; tem = TREE_CHAIN (tem))
6511 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode,
6512 EXPAND_MEMORY_USE_BAD);
6513 /* Flush the queue in case this parameter declaration has
6518 /* Make sure there is a line number after the function entry setup code. */
6519 force_next_line_note ();
6522 /* Undo the effects of init_dummy_function_start. */
6524 expand_dummy_function_end ()
6526 /* End any sequences that failed to be closed due to syntax errors. */
6527 while (in_sequence_p ())
6530 /* Outside function body, can't compute type's actual size
6531 until next function's body starts. */
6533 free_after_parsing (cfun);
6534 free_after_compilation (cfun);
6539 /* Call DOIT for each hard register used as a return value from
6540 the current function. */
6543 diddle_return_value (doit, arg)
6544 void (*doit) PARAMS ((rtx, void *));
6547 rtx outgoing = current_function_return_rtx;
6553 pcc = (current_function_returns_struct
6554 || current_function_returns_pcc_struct);
6556 if ((GET_CODE (outgoing) == REG
6557 && REGNO (outgoing) >= FIRST_PSEUDO_REGISTER)
6560 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
6562 /* A PCC-style return returns a pointer to the memory in which
6563 the structure is stored. */
6565 type = build_pointer_type (type);
6567 #ifdef FUNCTION_OUTGOING_VALUE
6568 outgoing = FUNCTION_OUTGOING_VALUE (type, current_function_decl);
6570 outgoing = FUNCTION_VALUE (type, current_function_decl);
6572 /* If this is a BLKmode structure being returned in registers, then use
6573 the mode computed in expand_return. */
6574 if (GET_MODE (outgoing) == BLKmode)
6575 PUT_MODE (outgoing, GET_MODE (current_function_return_rtx));
6576 REG_FUNCTION_VALUE_P (outgoing) = 1;
6579 if (GET_CODE (outgoing) == REG)
6580 (*doit) (outgoing, arg);
6581 else if (GET_CODE (outgoing) == PARALLEL)
6585 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6587 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6589 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6596 do_clobber_return_reg (reg, arg)
6598 void *arg ATTRIBUTE_UNUSED;
6600 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6604 clobber_return_register ()
6606 diddle_return_value (do_clobber_return_reg, NULL);
6610 do_use_return_reg (reg, arg)
6612 void *arg ATTRIBUTE_UNUSED;
6614 emit_insn (gen_rtx_USE (VOIDmode, reg));
6618 use_return_register ()
6620 diddle_return_value (do_use_return_reg, NULL);
6623 /* Generate RTL for the end of the current function.
6624 FILENAME and LINE are the current position in the source file.
6626 It is up to language-specific callers to do cleanups for parameters--
6627 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
6630 expand_function_end (filename, line, end_bindings)
6631 const char *filename;
6637 #ifdef TRAMPOLINE_TEMPLATE
6638 static rtx initial_trampoline;
6641 finish_expr_for_function ();
6643 #ifdef NON_SAVING_SETJMP
6644 /* Don't put any variables in registers if we call setjmp
6645 on a machine that fails to restore the registers. */
6646 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6648 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6649 setjmp_protect (DECL_INITIAL (current_function_decl));
6651 setjmp_protect_args ();
6655 /* Save the argument pointer if a save area was made for it. */
6656 if (arg_pointer_save_area)
6658 /* arg_pointer_save_area may not be a valid memory address, so we
6659 have to check it and fix it if necessary. */
6662 emit_move_insn (validize_mem (arg_pointer_save_area),
6663 virtual_incoming_args_rtx);
6664 seq = gen_sequence ();
6666 emit_insn_before (seq, tail_recursion_reentry);
6669 /* Initialize any trampolines required by this function. */
6670 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6672 tree function = TREE_PURPOSE (link);
6673 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6674 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6675 #ifdef TRAMPOLINE_TEMPLATE
6680 #ifdef TRAMPOLINE_TEMPLATE
6681 /* First make sure this compilation has a template for
6682 initializing trampolines. */
6683 if (initial_trampoline == 0)
6686 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6688 ggc_add_rtx_root (&initial_trampoline, 1);
6692 /* Generate insns to initialize the trampoline. */
6694 tramp = round_trampoline_addr (XEXP (tramp, 0));
6695 #ifdef TRAMPOLINE_TEMPLATE
6696 blktramp = change_address (initial_trampoline, BLKmode, tramp);
6697 emit_block_move (blktramp, initial_trampoline,
6698 GEN_INT (TRAMPOLINE_SIZE),
6699 TRAMPOLINE_ALIGNMENT);
6701 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6705 /* Put those insns at entry to the containing function (this one). */
6706 emit_insns_before (seq, tail_recursion_reentry);
6709 /* If we are doing stack checking and this function makes calls,
6710 do a stack probe at the start of the function to ensure we have enough
6711 space for another stack frame. */
6712 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6716 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6717 if (GET_CODE (insn) == CALL_INSN)
6720 probe_stack_range (STACK_CHECK_PROTECT,
6721 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6724 emit_insns_before (seq, tail_recursion_reentry);
6729 /* Warn about unused parms if extra warnings were specified. */
6730 /* Either ``-W -Wunused'' or ``-Wunused-parameter'' enables this
6731 warning. WARN_UNUSED_PARAMETER is negative when set by
6733 if (warn_unused_parameter > 0
6734 || (warn_unused_parameter < 0 && extra_warnings))
6738 for (decl = DECL_ARGUMENTS (current_function_decl);
6739 decl; decl = TREE_CHAIN (decl))
6740 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6741 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6742 warning_with_decl (decl, "unused parameter `%s'");
6745 /* Delete handlers for nonlocal gotos if nothing uses them. */
6746 if (nonlocal_goto_handler_slots != 0
6747 && ! current_function_has_nonlocal_label)
6750 /* End any sequences that failed to be closed due to syntax errors. */
6751 while (in_sequence_p ())
6754 /* Outside function body, can't compute type's actual size
6755 until next function's body starts. */
6756 immediate_size_expand--;
6758 clear_pending_stack_adjust ();
6759 do_pending_stack_adjust ();
6761 /* Mark the end of the function body.
6762 If control reaches this insn, the function can drop through
6763 without returning a value. */
6764 emit_note (NULL_PTR, NOTE_INSN_FUNCTION_END);
6766 /* Must mark the last line number note in the function, so that the test
6767 coverage code can avoid counting the last line twice. This just tells
6768 the code to ignore the immediately following line note, since there
6769 already exists a copy of this note somewhere above. This line number
6770 note is still needed for debugging though, so we can't delete it. */
6771 if (flag_test_coverage)
6772 emit_note (NULL_PTR, NOTE_INSN_REPEATED_LINE_NUMBER);
6774 /* Output a linenumber for the end of the function.
6775 SDB depends on this. */
6776 emit_line_note_force (filename, line);
6778 /* Output the label for the actual return from the function,
6779 if one is expected. This happens either because a function epilogue
6780 is used instead of a return instruction, or because a return was done
6781 with a goto in order to run local cleanups, or because of pcc-style
6782 structure returning. */
6788 /* Before the return label, clobber the return registers so that
6789 they are not propogated live to the rest of the function. This
6790 can only happen with functions that drop through; if there had
6791 been a return statement, there would have either been a return
6792 rtx, or a jump to the return label. */
6794 before = get_last_insn ();
6795 clobber_return_register ();
6796 after = get_last_insn ();
6798 if (before != after)
6799 cfun->x_clobber_return_insn = after;
6801 emit_label (return_label);
6804 /* C++ uses this. */
6806 expand_end_bindings (0, 0, 0);
6808 if (current_function_instrument_entry_exit)
6810 rtx fun = DECL_RTL (current_function_decl);
6811 if (GET_CODE (fun) == MEM)
6812 fun = XEXP (fun, 0);
6815 emit_library_call (profile_function_exit_libfunc, 0, VOIDmode, 2,
6817 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6819 hard_frame_pointer_rtx),
6823 /* Let except.c know where it should emit the call to unregister
6824 the function context for sjlj exceptions. */
6825 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
6826 sjlj_emit_function_exit_after (get_last_insn ());
6828 /* If we had calls to alloca, and this machine needs
6829 an accurate stack pointer to exit the function,
6830 insert some code to save and restore the stack pointer. */
6831 #ifdef EXIT_IGNORE_STACK
6832 if (! EXIT_IGNORE_STACK)
6834 if (current_function_calls_alloca)
6838 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
6839 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
6842 /* If scalar return value was computed in a pseudo-reg, or was a named
6843 return value that got dumped to the stack, copy that to the hard
6845 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6847 tree decl_result = DECL_RESULT (current_function_decl);
6848 rtx decl_rtl = DECL_RTL (decl_result);
6850 if (REG_P (decl_rtl)
6851 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
6852 : DECL_REGISTER (decl_result))
6856 #ifdef FUNCTION_OUTGOING_VALUE
6857 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
6858 current_function_decl);
6860 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
6861 current_function_decl);
6863 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
6865 /* If this is a BLKmode structure being returned in registers,
6866 then use the mode computed in expand_return. Note that if
6867 decl_rtl is memory, then its mode may have been changed,
6868 but that current_function_return_rtx has not. */
6869 if (GET_MODE (real_decl_rtl) == BLKmode)
6870 PUT_MODE (real_decl_rtl, GET_MODE (current_function_return_rtx));
6872 /* If a named return value dumped decl_return to memory, then
6873 we may need to re-do the PROMOTE_MODE signed/unsigned
6875 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
6877 int unsignedp = TREE_UNSIGNED (TREE_TYPE (decl_result));
6879 #ifdef PROMOTE_FUNCTION_RETURN
6880 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
6884 convert_move (real_decl_rtl, decl_rtl, unsignedp);
6887 emit_move_insn (real_decl_rtl, decl_rtl);
6889 /* The delay slot scheduler assumes that current_function_return_rtx
6890 holds the hard register containing the return value, not a
6891 temporary pseudo. */
6892 current_function_return_rtx = real_decl_rtl;
6896 /* If returning a structure, arrange to return the address of the value
6897 in a place where debuggers expect to find it.
6899 If returning a structure PCC style,
6900 the caller also depends on this value.
6901 And current_function_returns_pcc_struct is not necessarily set. */
6902 if (current_function_returns_struct
6903 || current_function_returns_pcc_struct)
6906 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
6907 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
6908 #ifdef FUNCTION_OUTGOING_VALUE
6910 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
6911 current_function_decl);
6914 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
6917 /* Mark this as a function return value so integrate will delete the
6918 assignment and USE below when inlining this function. */
6919 REG_FUNCTION_VALUE_P (outgoing) = 1;
6921 #ifdef POINTERS_EXTEND_UNSIGNED
6922 /* The address may be ptr_mode and OUTGOING may be Pmode. */
6923 if (GET_MODE (outgoing) != GET_MODE (value_address))
6924 value_address = convert_memory_address (GET_MODE (outgoing),
6928 emit_move_insn (outgoing, value_address);
6930 /* Show return register used to hold result (in this case the address
6932 current_function_return_rtx = outgoing;
6935 /* If this is an implementation of throw, do what's necessary to
6936 communicate between __builtin_eh_return and the epilogue. */
6937 expand_eh_return ();
6939 /* ??? This should no longer be necessary since stupid is no longer with
6940 us, but there are some parts of the compiler (eg reload_combine, and
6941 sh mach_dep_reorg) that still try and compute their own lifetime info
6942 instead of using the general framework. */
6943 use_return_register ();
6945 /* Output a return insn if we are using one.
6946 Otherwise, let the rtl chain end here, to drop through
6947 into the epilogue. */
6952 emit_jump_insn (gen_return ());
6957 /* Fix up any gotos that jumped out to the outermost
6958 binding level of the function.
6959 Must follow emitting RETURN_LABEL. */
6961 /* If you have any cleanups to do at this point,
6962 and they need to create temporary variables,
6963 then you will lose. */
6964 expand_fixups (get_insns ());
6967 /* Extend a vector that records the INSN_UIDs of INSNS (either a
6968 sequence or a single insn). */
6971 record_insns (insns, vecp)
6975 if (GET_CODE (insns) == SEQUENCE)
6977 int len = XVECLEN (insns, 0);
6978 int i = VARRAY_SIZE (*vecp);
6980 VARRAY_GROW (*vecp, i + len);
6983 VARRAY_INT (*vecp, i) = INSN_UID (XVECEXP (insns, 0, len));
6989 int i = VARRAY_SIZE (*vecp);
6990 VARRAY_GROW (*vecp, i + 1);
6991 VARRAY_INT (*vecp, i) = INSN_UID (insns);
6995 /* Determine how many INSN_UIDs in VEC are part of INSN. */
6998 contains (insn, vec)
7004 if (GET_CODE (insn) == INSN
7005 && GET_CODE (PATTERN (insn)) == SEQUENCE)
7008 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
7009 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7010 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
7016 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7017 if (INSN_UID (insn) == VARRAY_INT (vec, j))
7024 prologue_epilogue_contains (insn)
7027 if (contains (insn, prologue))
7029 if (contains (insn, epilogue))
7035 sibcall_epilogue_contains (insn)
7038 if (sibcall_epilogue)
7039 return contains (insn, sibcall_epilogue);
7044 /* Insert gen_return at the end of block BB. This also means updating
7045 block_for_insn appropriately. */
7048 emit_return_into_block (bb, line_note)
7054 p = NEXT_INSN (bb->end);
7055 end = emit_jump_insn_after (gen_return (), bb->end);
7057 emit_line_note_after (NOTE_SOURCE_FILE (line_note),
7058 NOTE_LINE_NUMBER (line_note), bb->end);
7062 set_block_for_insn (p, bb);
7069 #endif /* HAVE_return */
7071 #ifdef HAVE_epilogue
7073 /* Modify SEQ, a SEQUENCE that is part of the epilogue, to no modifications
7074 to the stack pointer. */
7077 keep_stack_depressed (seq)
7081 rtx sp_from_reg = 0;
7082 int sp_modified_unknown = 0;
7084 /* If the epilogue is just a single instruction, it's OK as is */
7086 if (GET_CODE (seq) != SEQUENCE)
7089 /* Scan all insns in SEQ looking for ones that modified the stack
7090 pointer. Record if it modified the stack pointer by copying it
7091 from the frame pointer or if it modified it in some other way.
7092 Then modify any subsequent stack pointer references to take that
7093 into account. We start by only allowing SP to be copied from a
7094 register (presumably FP) and then be subsequently referenced. */
7096 for (i = 0; i < XVECLEN (seq, 0); i++)
7098 rtx insn = XVECEXP (seq, 0, i);
7100 if (GET_RTX_CLASS (GET_CODE (insn)) != 'i')
7103 if (reg_set_p (stack_pointer_rtx, insn))
7105 rtx set = single_set (insn);
7107 /* If SP is set as a side-effect, we can't support this. */
7111 if (GET_CODE (SET_SRC (set)) == REG)
7112 sp_from_reg = SET_SRC (set);
7114 sp_modified_unknown = 1;
7116 /* Don't allow the SP modification to happen. */
7117 PUT_CODE (insn, NOTE);
7118 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
7119 NOTE_SOURCE_FILE (insn) = 0;
7121 else if (reg_referenced_p (stack_pointer_rtx, PATTERN (insn)))
7123 if (sp_modified_unknown)
7126 else if (sp_from_reg != 0)
7128 = replace_rtx (PATTERN (insn), stack_pointer_rtx, sp_from_reg);
7134 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7135 this into place with notes indicating where the prologue ends and where
7136 the epilogue begins. Update the basic block information when possible. */
7139 thread_prologue_and_epilogue_insns (f)
7140 rtx f ATTRIBUTE_UNUSED;
7145 #ifdef HAVE_prologue
7146 rtx prologue_end = NULL_RTX;
7148 #if defined (HAVE_epilogue) || defined(HAVE_return)
7149 rtx epilogue_end = NULL_RTX;
7152 #ifdef HAVE_prologue
7156 seq = gen_prologue ();
7159 /* Retain a map of the prologue insns. */
7160 if (GET_CODE (seq) != SEQUENCE)
7162 record_insns (seq, &prologue);
7163 prologue_end = emit_note (NULL, NOTE_INSN_PROLOGUE_END);
7165 seq = gen_sequence ();
7168 /* If optimization is off, and perhaps in an empty function,
7169 the entry block will have no successors. */
7170 if (ENTRY_BLOCK_PTR->succ)
7172 /* Can't deal with multiple successsors of the entry block. */
7173 if (ENTRY_BLOCK_PTR->succ->succ_next)
7176 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
7180 emit_insn_after (seq, f);
7184 /* If the exit block has no non-fake predecessors, we don't need
7186 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7187 if ((e->flags & EDGE_FAKE) == 0)
7193 if (optimize && HAVE_return)
7195 /* If we're allowed to generate a simple return instruction,
7196 then by definition we don't need a full epilogue. Examine
7197 the block that falls through to EXIT. If it does not
7198 contain any code, examine its predecessors and try to
7199 emit (conditional) return instructions. */
7205 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7206 if (e->flags & EDGE_FALLTHRU)
7212 /* Verify that there are no active instructions in the last block. */
7214 while (label && GET_CODE (label) != CODE_LABEL)
7216 if (active_insn_p (label))
7218 label = PREV_INSN (label);
7221 if (last->head == label && GET_CODE (label) == CODE_LABEL)
7223 rtx epilogue_line_note = NULL_RTX;
7225 /* Locate the line number associated with the closing brace,
7226 if we can find one. */
7227 for (seq = get_last_insn ();
7228 seq && ! active_insn_p (seq);
7229 seq = PREV_INSN (seq))
7230 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
7232 epilogue_line_note = seq;
7236 for (e = last->pred; e; e = e_next)
7238 basic_block bb = e->src;
7241 e_next = e->pred_next;
7242 if (bb == ENTRY_BLOCK_PTR)
7246 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
7249 /* If we have an unconditional jump, we can replace that
7250 with a simple return instruction. */
7251 if (simplejump_p (jump))
7253 emit_return_into_block (bb, epilogue_line_note);
7254 flow_delete_insn (jump);
7257 /* If we have a conditional jump, we can try to replace
7258 that with a conditional return instruction. */
7259 else if (condjump_p (jump))
7263 ret = SET_SRC (PATTERN (jump));
7264 if (GET_CODE (XEXP (ret, 1)) == LABEL_REF)
7265 loc = &XEXP (ret, 1);
7267 loc = &XEXP (ret, 2);
7268 ret = gen_rtx_RETURN (VOIDmode);
7270 if (! validate_change (jump, loc, ret, 0))
7272 if (JUMP_LABEL (jump))
7273 LABEL_NUSES (JUMP_LABEL (jump))--;
7275 /* If this block has only one successor, it both jumps
7276 and falls through to the fallthru block, so we can't
7278 if (bb->succ->succ_next == NULL)
7284 /* Fix up the CFG for the successful change we just made. */
7285 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7288 /* Emit a return insn for the exit fallthru block. Whether
7289 this is still reachable will be determined later. */
7291 emit_barrier_after (last->end);
7292 emit_return_into_block (last, epilogue_line_note);
7293 epilogue_end = last->end;
7298 #ifdef HAVE_epilogue
7301 /* Find the edge that falls through to EXIT. Other edges may exist
7302 due to RETURN instructions, but those don't need epilogues.
7303 There really shouldn't be a mixture -- either all should have
7304 been converted or none, however... */
7306 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7307 if (e->flags & EDGE_FALLTHRU)
7313 epilogue_end = emit_note (NULL, NOTE_INSN_EPILOGUE_BEG);
7315 seq = gen_epilogue ();
7317 /* If this function returns with the stack depressed, massage
7318 the epilogue to actually do that. */
7319 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7320 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7321 keep_stack_depressed (seq);
7323 emit_jump_insn (seq);
7325 /* Retain a map of the epilogue insns. */
7326 if (GET_CODE (seq) != SEQUENCE)
7328 record_insns (seq, &epilogue);
7330 seq = gen_sequence ();
7333 insert_insn_on_edge (seq, e);
7340 commit_edge_insertions ();
7342 #ifdef HAVE_sibcall_epilogue
7343 /* Emit sibling epilogues before any sibling call sites. */
7344 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7346 basic_block bb = e->src;
7351 if (GET_CODE (insn) != CALL_INSN
7352 || ! SIBLING_CALL_P (insn))
7356 seq = gen_sibcall_epilogue ();
7359 i = PREV_INSN (insn);
7360 newinsn = emit_insn_before (seq, insn);
7362 /* Update the UID to basic block map. */
7363 for (i = NEXT_INSN (i); i != insn; i = NEXT_INSN (i))
7364 set_block_for_insn (i, bb);
7366 /* Retain a map of the epilogue insns. Used in life analysis to
7367 avoid getting rid of sibcall epilogue insns. */
7368 record_insns (GET_CODE (seq) == SEQUENCE
7369 ? seq : newinsn, &sibcall_epilogue);
7373 #ifdef HAVE_prologue
7378 /* GDB handles `break f' by setting a breakpoint on the first
7379 line note after the prologue. Which means (1) that if
7380 there are line number notes before where we inserted the
7381 prologue we should move them, and (2) we should generate a
7382 note before the end of the first basic block, if there isn't
7385 ??? This behaviour is completely broken when dealing with
7386 multiple entry functions. We simply place the note always
7387 into first basic block and let alternate entry points
7391 for (insn = prologue_end; insn; insn = prev)
7393 prev = PREV_INSN (insn);
7394 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7396 /* Note that we cannot reorder the first insn in the
7397 chain, since rest_of_compilation relies on that
7398 remaining constant. */
7401 reorder_insns (insn, insn, prologue_end);
7405 /* Find the last line number note in the first block. */
7406 for (insn = BASIC_BLOCK (0)->end;
7407 insn != prologue_end && insn;
7408 insn = PREV_INSN (insn))
7409 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7412 /* If we didn't find one, make a copy of the first line number
7416 for (insn = next_active_insn (prologue_end);
7418 insn = PREV_INSN (insn))
7419 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7421 emit_line_note_after (NOTE_SOURCE_FILE (insn),
7422 NOTE_LINE_NUMBER (insn),
7429 #ifdef HAVE_epilogue
7434 /* Similarly, move any line notes that appear after the epilogue.
7435 There is no need, however, to be quite so anal about the existance
7437 for (insn = epilogue_end; insn; insn = next)
7439 next = NEXT_INSN (insn);
7440 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7441 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7447 /* Reposition the prologue-end and epilogue-begin notes after instruction
7448 scheduling and delayed branch scheduling. */
7451 reposition_prologue_and_epilogue_notes (f)
7452 rtx f ATTRIBUTE_UNUSED;
7454 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7457 if ((len = VARRAY_SIZE (prologue)) > 0)
7459 register rtx insn, note = 0;
7461 /* Scan from the beginning until we reach the last prologue insn.
7462 We apparently can't depend on basic_block_{head,end} after
7464 for (insn = f; len && insn; insn = NEXT_INSN (insn))
7466 if (GET_CODE (insn) == NOTE)
7468 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
7471 else if ((len -= contains (insn, prologue)) == 0)
7474 /* Find the prologue-end note if we haven't already, and
7475 move it to just after the last prologue insn. */
7478 for (note = insn; (note = NEXT_INSN (note));)
7479 if (GET_CODE (note) == NOTE
7480 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
7484 next = NEXT_INSN (note);
7486 /* Whether or not we can depend on BLOCK_HEAD,
7487 attempt to keep it up-to-date. */
7488 if (BLOCK_HEAD (0) == note)
7489 BLOCK_HEAD (0) = next;
7492 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
7493 if (GET_CODE (insn) == CODE_LABEL)
7494 insn = NEXT_INSN (insn);
7495 add_insn_after (note, insn);
7500 if ((len = VARRAY_SIZE (epilogue)) > 0)
7502 register rtx insn, note = 0;
7504 /* Scan from the end until we reach the first epilogue insn.
7505 We apparently can't depend on basic_block_{head,end} after
7507 for (insn = get_last_insn (); len && insn; insn = PREV_INSN (insn))
7509 if (GET_CODE (insn) == NOTE)
7511 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
7514 else if ((len -= contains (insn, epilogue)) == 0)
7516 /* Find the epilogue-begin note if we haven't already, and
7517 move it to just before the first epilogue insn. */
7520 for (note = insn; (note = PREV_INSN (note));)
7521 if (GET_CODE (note) == NOTE
7522 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
7526 /* Whether or not we can depend on BLOCK_HEAD,
7527 attempt to keep it up-to-date. */
7529 && BLOCK_HEAD (n_basic_blocks-1) == insn)
7530 BLOCK_HEAD (n_basic_blocks-1) = note;
7533 add_insn_before (note, insn);
7537 #endif /* HAVE_prologue or HAVE_epilogue */
7540 /* Mark T for GC. */
7544 struct temp_slot *t;
7548 ggc_mark_rtx (t->slot);
7549 ggc_mark_rtx (t->address);
7550 ggc_mark_tree (t->rtl_expr);
7551 ggc_mark_tree (t->type);
7557 /* Mark P for GC. */
7560 mark_function_status (p)
7569 ggc_mark_rtx (p->arg_offset_rtx);
7571 if (p->x_parm_reg_stack_loc)
7572 for (i = p->x_max_parm_reg, r = p->x_parm_reg_stack_loc;
7576 ggc_mark_rtx (p->return_rtx);
7577 ggc_mark_rtx (p->x_cleanup_label);
7578 ggc_mark_rtx (p->x_return_label);
7579 ggc_mark_rtx (p->x_save_expr_regs);
7580 ggc_mark_rtx (p->x_stack_slot_list);
7581 ggc_mark_rtx (p->x_parm_birth_insn);
7582 ggc_mark_rtx (p->x_tail_recursion_label);
7583 ggc_mark_rtx (p->x_tail_recursion_reentry);
7584 ggc_mark_rtx (p->internal_arg_pointer);
7585 ggc_mark_rtx (p->x_arg_pointer_save_area);
7586 ggc_mark_tree (p->x_rtl_expr_chain);
7587 ggc_mark_rtx (p->x_last_parm_insn);
7588 ggc_mark_tree (p->x_context_display);
7589 ggc_mark_tree (p->x_trampoline_list);
7590 ggc_mark_rtx (p->epilogue_delay_list);
7591 ggc_mark_rtx (p->x_clobber_return_insn);
7593 mark_temp_slot (p->x_temp_slots);
7596 struct var_refs_queue *q = p->fixup_var_refs_queue;
7599 ggc_mark_rtx (q->modified);
7604 ggc_mark_rtx (p->x_nonlocal_goto_handler_slots);
7605 ggc_mark_rtx (p->x_nonlocal_goto_handler_labels);
7606 ggc_mark_rtx (p->x_nonlocal_goto_stack_level);
7607 ggc_mark_tree (p->x_nonlocal_labels);
7610 /* Mark the function chain ARG (which is really a struct function **)
7614 mark_function_chain (arg)
7617 struct function *f = *(struct function **) arg;
7619 for (; f; f = f->next_global)
7621 ggc_mark_tree (f->decl);
7623 mark_function_status (f);
7624 mark_eh_status (f->eh);
7625 mark_stmt_status (f->stmt);
7626 mark_expr_status (f->expr);
7627 mark_emit_status (f->emit);
7628 mark_varasm_status (f->varasm);
7630 if (mark_machine_status)
7631 (*mark_machine_status) (f);
7632 if (mark_lang_status)
7633 (*mark_lang_status) (f);
7635 if (f->original_arg_vector)
7636 ggc_mark_rtvec ((rtvec) f->original_arg_vector);
7637 if (f->original_decl_initial)
7638 ggc_mark_tree (f->original_decl_initial);
7642 /* Called once, at initialization, to initialize function.c. */
7645 init_function_once ()
7647 ggc_add_root (&all_functions, 1, sizeof all_functions,
7648 mark_function_chain);
7650 VARRAY_INT_INIT (prologue, 0, "prologue");
7651 VARRAY_INT_INIT (epilogue, 0, "epilogue");
7652 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");