1 /* Expands front end tree to back end RTL for GNU C-Compiler
2 Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000 Free Software Foundation, Inc.
5 This file is part of GNU CC.
7 GNU CC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GNU CC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU CC; see the file COPYING. If not, write to
19 the Free Software Foundation, 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
23 /* This file handles the generation of rtl code from tree structure
24 at the level of the function as a whole.
25 It creates the rtl expressions for parameters and auto variables
26 and has full responsibility for allocating stack slots.
28 `expand_function_start' is called at the beginning of a function,
29 before the function body is parsed, and `expand_function_end' is
30 called after parsing the body.
32 Call `assign_stack_local' to allocate a stack slot for a local variable.
33 This is usually done during the RTL generation for the function body,
34 but it can also be done in the reload pass when a pseudo-register does
35 not get a hard register.
37 Call `put_var_into_stack' when you learn, belatedly, that a variable
38 previously given a pseudo-register must in fact go in the stack.
39 This function changes the DECL_RTL to be a stack slot instead of a reg
40 then scans all the RTL instructions so far generated to correct them. */
49 #include "insn-flags.h"
51 #include "insn-codes.h"
53 #include "hard-reg-set.h"
54 #include "insn-config.h"
57 #include "basic-block.h"
64 #ifndef ACCUMULATE_OUTGOING_ARGS
65 #define ACCUMULATE_OUTGOING_ARGS 0
68 #ifndef TRAMPOLINE_ALIGNMENT
69 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
72 #ifndef LOCAL_ALIGNMENT
73 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
76 #if !defined (PREFERRED_STACK_BOUNDARY) && defined (STACK_BOUNDARY)
77 #define PREFERRED_STACK_BOUNDARY STACK_BOUNDARY
80 /* Some systems use __main in a way incompatible with its use in gcc, in these
81 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
82 give the same symbol without quotes for an alternative entry point. You
83 must define both, or neither. */
85 #define NAME__MAIN "__main"
86 #define SYMBOL__MAIN __main
89 /* Round a value to the lowest integer less than it that is a multiple of
90 the required alignment. Avoid using division in case the value is
91 negative. Assume the alignment is a power of two. */
92 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
94 /* Similar, but round to the next highest integer that meets the
96 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
98 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
99 during rtl generation. If they are different register numbers, this is
100 always true. It may also be true if
101 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
102 generation. See fix_lexical_addr for details. */
104 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
105 #define NEED_SEPARATE_AP
108 /* Nonzero if function being compiled doesn't contain any calls
109 (ignoring the prologue and epilogue). This is set prior to
110 local register allocation and is valid for the remaining
112 int current_function_is_leaf;
114 /* Nonzero if function being compiled doesn't contain any instructions
115 that can throw an exception. This is set prior to final. */
117 int current_function_nothrow;
119 /* Nonzero if function being compiled doesn't modify the stack pointer
120 (ignoring the prologue and epilogue). This is only valid after
121 life_analysis has run. */
122 int current_function_sp_is_unchanging;
124 /* Nonzero if the function being compiled is a leaf function which only
125 uses leaf registers. This is valid after reload (specifically after
126 sched2) and is useful only if the port defines LEAF_REGISTERS. */
127 int current_function_uses_only_leaf_regs;
129 /* Nonzero once virtual register instantiation has been done.
130 assign_stack_local uses frame_pointer_rtx when this is nonzero. */
131 static int virtuals_instantiated;
133 /* These variables hold pointers to functions to
134 save and restore machine-specific data,
135 in push_function_context and pop_function_context. */
136 void (*init_machine_status) PARAMS ((struct function *));
137 void (*save_machine_status) PARAMS ((struct function *));
138 void (*restore_machine_status) PARAMS ((struct function *));
139 void (*mark_machine_status) PARAMS ((struct function *));
140 void (*free_machine_status) PARAMS ((struct function *));
142 /* Likewise, but for language-specific data. */
143 void (*init_lang_status) PARAMS ((struct function *));
144 void (*save_lang_status) PARAMS ((struct function *));
145 void (*restore_lang_status) PARAMS ((struct function *));
146 void (*mark_lang_status) PARAMS ((struct function *));
147 void (*free_lang_status) PARAMS ((struct function *));
149 /* The FUNCTION_DECL for an inline function currently being expanded. */
150 tree inline_function_decl;
152 /* The currently compiled function. */
153 struct function *cfun = 0;
155 /* Global list of all compiled functions. */
156 struct function *all_functions = 0;
158 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
159 static varray_type prologue;
160 static varray_type epilogue;
162 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
164 static varray_type sibcall_epilogue;
166 /* In order to evaluate some expressions, such as function calls returning
167 structures in memory, we need to temporarily allocate stack locations.
168 We record each allocated temporary in the following structure.
170 Associated with each temporary slot is a nesting level. When we pop up
171 one level, all temporaries associated with the previous level are freed.
172 Normally, all temporaries are freed after the execution of the statement
173 in which they were created. However, if we are inside a ({...}) grouping,
174 the result may be in a temporary and hence must be preserved. If the
175 result could be in a temporary, we preserve it if we can determine which
176 one it is in. If we cannot determine which temporary may contain the
177 result, all temporaries are preserved. A temporary is preserved by
178 pretending it was allocated at the previous nesting level.
180 Automatic variables are also assigned temporary slots, at the nesting
181 level where they are defined. They are marked a "kept" so that
182 free_temp_slots will not free them. */
186 /* Points to next temporary slot. */
187 struct temp_slot *next;
188 /* The rtx to used to reference the slot. */
190 /* The rtx used to represent the address if not the address of the
191 slot above. May be an EXPR_LIST if multiple addresses exist. */
193 /* The alignment (in bits) of the slot. */
195 /* The size, in units, of the slot. */
197 /* The alias set for the slot. If the alias set is zero, we don't
198 know anything about the alias set of the slot. We must only
199 reuse a slot if it is assigned an object of the same alias set.
200 Otherwise, the rest of the compiler may assume that the new use
201 of the slot cannot alias the old use of the slot, which is
202 false. If the slot has alias set zero, then we can't reuse the
203 slot at all, since we have no idea what alias set may have been
204 imposed on the memory. For example, if the stack slot is the
205 call frame for an inline functioned, we have no idea what alias
206 sets will be assigned to various pieces of the call frame. */
207 HOST_WIDE_INT alias_set;
208 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
210 /* Non-zero if this temporary is currently in use. */
212 /* Non-zero if this temporary has its address taken. */
214 /* Nesting level at which this slot is being used. */
216 /* Non-zero if this should survive a call to free_temp_slots. */
218 /* The offset of the slot from the frame_pointer, including extra space
219 for alignment. This info is for combine_temp_slots. */
220 HOST_WIDE_INT base_offset;
221 /* The size of the slot, including extra space for alignment. This
222 info is for combine_temp_slots. */
223 HOST_WIDE_INT full_size;
226 /* This structure is used to record MEMs or pseudos used to replace VAR, any
227 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
228 maintain this list in case two operands of an insn were required to match;
229 in that case we must ensure we use the same replacement. */
231 struct fixup_replacement
235 struct fixup_replacement *next;
238 struct insns_for_mem_entry {
239 /* The KEY in HE will be a MEM. */
240 struct hash_entry he;
241 /* These are the INSNS which reference the MEM. */
245 /* Forward declarations. */
247 static rtx assign_stack_local_1 PARAMS ((enum machine_mode, HOST_WIDE_INT,
248 int, struct function *));
249 static rtx assign_stack_temp_for_type PARAMS ((enum machine_mode,
250 HOST_WIDE_INT, int, tree));
251 static struct temp_slot *find_temp_slot_from_address PARAMS ((rtx));
252 static void put_reg_into_stack PARAMS ((struct function *, rtx, tree,
253 enum machine_mode, enum machine_mode,
254 int, unsigned int, int,
255 struct hash_table *));
256 static void fixup_var_refs PARAMS ((rtx, enum machine_mode, int,
257 struct hash_table *));
258 static struct fixup_replacement
259 *find_fixup_replacement PARAMS ((struct fixup_replacement **, rtx));
260 static void fixup_var_refs_insns PARAMS ((rtx, enum machine_mode, int,
261 rtx, int, struct hash_table *));
262 static void fixup_var_refs_1 PARAMS ((rtx, enum machine_mode, rtx *, rtx,
263 struct fixup_replacement **));
264 static rtx fixup_memory_subreg PARAMS ((rtx, rtx, int));
265 static rtx walk_fixup_memory_subreg PARAMS ((rtx, rtx, int));
266 static rtx fixup_stack_1 PARAMS ((rtx, rtx));
267 static void optimize_bit_field PARAMS ((rtx, rtx, rtx *));
268 static void instantiate_decls PARAMS ((tree, int));
269 static void instantiate_decls_1 PARAMS ((tree, int));
270 static void instantiate_decl PARAMS ((rtx, HOST_WIDE_INT, int));
271 static int instantiate_virtual_regs_1 PARAMS ((rtx *, rtx, int));
272 static void delete_handlers PARAMS ((void));
273 static void pad_to_arg_alignment PARAMS ((struct args_size *, int,
274 struct args_size *));
275 #ifndef ARGS_GROW_DOWNWARD
276 static void pad_below PARAMS ((struct args_size *, enum machine_mode,
279 #ifdef ARGS_GROW_DOWNWARD
280 static tree round_down PARAMS ((tree, int));
282 static rtx round_trampoline_addr PARAMS ((rtx));
283 static tree *identify_blocks_1 PARAMS ((rtx, tree *, tree *, tree *));
284 static void reorder_blocks_1 PARAMS ((rtx, tree, varray_type *));
285 static tree blocks_nreverse PARAMS ((tree));
286 static int all_blocks PARAMS ((tree, tree *));
287 static tree *get_block_vector PARAMS ((tree, int *));
288 /* We always define `record_insns' even if its not used so that we
289 can always export `prologue_epilogue_contains'. */
290 static void record_insns PARAMS ((rtx, varray_type *)) ATTRIBUTE_UNUSED;
291 static int contains PARAMS ((rtx, varray_type));
293 static void emit_return_into_block PARAMS ((basic_block, rtx));
295 static void put_addressof_into_stack PARAMS ((rtx, struct hash_table *));
296 static boolean purge_addressof_1 PARAMS ((rtx *, rtx, int, int,
297 struct hash_table *));
298 static int is_addressof PARAMS ((rtx *, void *));
299 static struct hash_entry *insns_for_mem_newfunc PARAMS ((struct hash_entry *,
302 static unsigned long insns_for_mem_hash PARAMS ((hash_table_key));
303 static boolean insns_for_mem_comp PARAMS ((hash_table_key, hash_table_key));
304 static int insns_for_mem_walk PARAMS ((rtx *, void *));
305 static void compute_insns_for_mem PARAMS ((rtx, rtx, struct hash_table *));
306 static void mark_temp_slot PARAMS ((struct temp_slot *));
307 static void mark_function_status PARAMS ((struct function *));
308 static void mark_function_chain PARAMS ((void *));
309 static void prepare_function_start PARAMS ((void));
310 static void do_clobber_return_reg PARAMS ((rtx, void *));
311 static void do_use_return_reg PARAMS ((rtx, void *));
313 /* Pointer to chain of `struct function' for containing functions. */
314 struct function *outer_function_chain;
316 /* Given a function decl for a containing function,
317 return the `struct function' for it. */
320 find_function_data (decl)
325 for (p = outer_function_chain; p; p = p->next)
332 /* Save the current context for compilation of a nested function.
333 This is called from language-specific code. The caller should use
334 the save_lang_status callback to save any language-specific state,
335 since this function knows only about language-independent
339 push_function_context_to (context)
342 struct function *p, *context_data;
346 context_data = (context == current_function_decl
348 : find_function_data (context));
349 context_data->contains_functions = 1;
353 init_dummy_function_start ();
356 p->next = outer_function_chain;
357 outer_function_chain = p;
358 p->fixup_var_refs_queue = 0;
360 save_tree_status (p);
361 if (save_lang_status)
362 (*save_lang_status) (p);
363 if (save_machine_status)
364 (*save_machine_status) (p);
370 push_function_context ()
372 push_function_context_to (current_function_decl);
375 /* Restore the last saved context, at the end of a nested function.
376 This function is called from language-specific code. */
379 pop_function_context_from (context)
380 tree context ATTRIBUTE_UNUSED;
382 struct function *p = outer_function_chain;
383 struct var_refs_queue *queue;
384 struct var_refs_queue *next;
387 outer_function_chain = p->next;
389 current_function_decl = p->decl;
392 restore_tree_status (p);
393 restore_emit_status (p);
395 if (restore_machine_status)
396 (*restore_machine_status) (p);
397 if (restore_lang_status)
398 (*restore_lang_status) (p);
400 /* Finish doing put_var_into_stack for any of our variables
401 which became addressable during the nested function. */
402 for (queue = p->fixup_var_refs_queue; queue; queue = next)
405 fixup_var_refs (queue->modified, queue->promoted_mode,
406 queue->unsignedp, 0);
409 p->fixup_var_refs_queue = 0;
411 /* Reset variables that have known state during rtx generation. */
412 rtx_equal_function_value_matters = 1;
413 virtuals_instantiated = 0;
417 pop_function_context ()
419 pop_function_context_from (current_function_decl);
422 /* Clear out all parts of the state in F that can safely be discarded
423 after the function has been parsed, but not compiled, to let
424 garbage collection reclaim the memory. */
427 free_after_parsing (f)
430 /* f->expr->forced_labels is used by code generation. */
431 /* f->emit->regno_reg_rtx is used by code generation. */
432 /* f->varasm is used by code generation. */
433 /* f->eh->eh_return_stub_label is used by code generation. */
435 if (free_lang_status)
436 (*free_lang_status) (f);
437 free_stmt_status (f);
440 /* Clear out all parts of the state in F that can safely be discarded
441 after the function has been compiled, to let garbage collection
442 reclaim the memory. */
445 free_after_compilation (f)
448 struct temp_slot *ts;
449 struct temp_slot *next;
452 free_expr_status (f);
453 free_emit_status (f);
454 free_varasm_status (f);
456 if (free_machine_status)
457 (*free_machine_status) (f);
459 if (f->x_parm_reg_stack_loc)
460 free (f->x_parm_reg_stack_loc);
462 for (ts = f->x_temp_slots; ts; ts = next)
467 f->x_temp_slots = NULL;
469 f->arg_offset_rtx = NULL;
470 f->return_rtx = NULL;
471 f->internal_arg_pointer = NULL;
472 f->x_nonlocal_labels = NULL;
473 f->x_nonlocal_goto_handler_slots = NULL;
474 f->x_nonlocal_goto_handler_labels = NULL;
475 f->x_nonlocal_goto_stack_level = NULL;
476 f->x_cleanup_label = NULL;
477 f->x_return_label = NULL;
478 f->x_save_expr_regs = NULL;
479 f->x_stack_slot_list = NULL;
480 f->x_rtl_expr_chain = NULL;
481 f->x_tail_recursion_label = NULL;
482 f->x_tail_recursion_reentry = NULL;
483 f->x_arg_pointer_save_area = NULL;
484 f->x_context_display = NULL;
485 f->x_trampoline_list = NULL;
486 f->x_parm_birth_insn = NULL;
487 f->x_last_parm_insn = NULL;
488 f->x_parm_reg_stack_loc = NULL;
489 f->fixup_var_refs_queue = NULL;
490 f->original_arg_vector = NULL;
491 f->original_decl_initial = NULL;
492 f->inl_last_parm_insn = NULL;
493 f->epilogue_delay_list = NULL;
497 /* Allocate fixed slots in the stack frame of the current function. */
499 /* Return size needed for stack frame based on slots so far allocated in
501 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
502 the caller may have to do that. */
505 get_func_frame_size (f)
508 #ifdef FRAME_GROWS_DOWNWARD
509 return -f->x_frame_offset;
511 return f->x_frame_offset;
515 /* Return size needed for stack frame based on slots so far allocated.
516 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
517 the caller may have to do that. */
521 return get_func_frame_size (cfun);
524 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
525 with machine mode MODE.
527 ALIGN controls the amount of alignment for the address of the slot:
528 0 means according to MODE,
529 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
530 positive specifies alignment boundary in bits.
532 We do not round to stack_boundary here.
534 FUNCTION specifies the function to allocate in. */
537 assign_stack_local_1 (mode, size, align, function)
538 enum machine_mode mode;
541 struct function *function;
543 register rtx x, addr;
544 int bigend_correction = 0;
547 /* Allocate in the memory associated with the function in whose frame
549 if (function != cfun)
550 push_obstacks (function->function_obstack,
551 function->function_maybepermanent_obstack);
557 alignment = GET_MODE_ALIGNMENT (mode);
559 alignment = BIGGEST_ALIGNMENT;
561 /* Allow the target to (possibly) increase the alignment of this
563 type = type_for_mode (mode, 0);
565 alignment = LOCAL_ALIGNMENT (type, alignment);
567 alignment /= BITS_PER_UNIT;
569 else if (align == -1)
571 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
572 size = CEIL_ROUND (size, alignment);
575 alignment = align / BITS_PER_UNIT;
577 #ifdef FRAME_GROWS_DOWNWARD
578 function->x_frame_offset -= size;
581 /* Ignore alignment we can't do with expected alignment of the boundary. */
582 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
583 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
585 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
586 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
588 /* Round frame offset to that alignment.
589 We must be careful here, since FRAME_OFFSET might be negative and
590 division with a negative dividend isn't as well defined as we might
591 like. So we instead assume that ALIGNMENT is a power of two and
592 use logical operations which are unambiguous. */
593 #ifdef FRAME_GROWS_DOWNWARD
594 function->x_frame_offset = FLOOR_ROUND (function->x_frame_offset, alignment);
596 function->x_frame_offset = CEIL_ROUND (function->x_frame_offset, alignment);
599 /* On a big-endian machine, if we are allocating more space than we will use,
600 use the least significant bytes of those that are allocated. */
601 if (BYTES_BIG_ENDIAN && mode != BLKmode)
602 bigend_correction = size - GET_MODE_SIZE (mode);
604 /* If we have already instantiated virtual registers, return the actual
605 address relative to the frame pointer. */
606 if (function == cfun && virtuals_instantiated)
607 addr = plus_constant (frame_pointer_rtx,
608 (frame_offset + bigend_correction
609 + STARTING_FRAME_OFFSET));
611 addr = plus_constant (virtual_stack_vars_rtx,
612 function->x_frame_offset + bigend_correction);
614 #ifndef FRAME_GROWS_DOWNWARD
615 function->x_frame_offset += size;
618 x = gen_rtx_MEM (mode, addr);
620 function->x_stack_slot_list
621 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
623 if (function != cfun)
629 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
633 assign_stack_local (mode, size, align)
634 enum machine_mode mode;
638 return assign_stack_local_1 (mode, size, align, cfun);
641 /* Allocate a temporary stack slot and record it for possible later
644 MODE is the machine mode to be given to the returned rtx.
646 SIZE is the size in units of the space required. We do no rounding here
647 since assign_stack_local will do any required rounding.
649 KEEP is 1 if this slot is to be retained after a call to
650 free_temp_slots. Automatic variables for a block are allocated
651 with this flag. KEEP is 2 if we allocate a longer term temporary,
652 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
653 if we are to allocate something at an inner level to be treated as
654 a variable in the block (e.g., a SAVE_EXPR).
656 TYPE is the type that will be used for the stack slot. */
659 assign_stack_temp_for_type (mode, size, keep, type)
660 enum machine_mode mode;
666 HOST_WIDE_INT alias_set;
667 struct temp_slot *p, *best_p = 0;
669 /* If SIZE is -1 it means that somebody tried to allocate a temporary
670 of a variable size. */
674 /* If we know the alias set for the memory that will be used, use
675 it. If there's no TYPE, then we don't know anything about the
676 alias set for the memory. */
678 alias_set = get_alias_set (type);
682 align = GET_MODE_ALIGNMENT (mode);
684 align = BIGGEST_ALIGNMENT;
687 type = type_for_mode (mode, 0);
690 align = LOCAL_ALIGNMENT (type, align);
692 /* Try to find an available, already-allocated temporary of the proper
693 mode which meets the size and alignment requirements. Choose the
694 smallest one with the closest alignment. */
695 for (p = temp_slots; p; p = p->next)
696 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
698 && (! flag_strict_aliasing
699 || (alias_set && p->alias_set == alias_set))
700 && (best_p == 0 || best_p->size > p->size
701 || (best_p->size == p->size && best_p->align > p->align)))
703 if (p->align == align && p->size == size)
711 /* Make our best, if any, the one to use. */
714 /* If there are enough aligned bytes left over, make them into a new
715 temp_slot so that the extra bytes don't get wasted. Do this only
716 for BLKmode slots, so that we can be sure of the alignment. */
717 if (GET_MODE (best_p->slot) == BLKmode)
719 int alignment = best_p->align / BITS_PER_UNIT;
720 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
722 if (best_p->size - rounded_size >= alignment)
724 p = (struct temp_slot *) xmalloc (sizeof (struct temp_slot));
725 p->in_use = p->addr_taken = 0;
726 p->size = best_p->size - rounded_size;
727 p->base_offset = best_p->base_offset + rounded_size;
728 p->full_size = best_p->full_size - rounded_size;
729 p->slot = gen_rtx_MEM (BLKmode,
730 plus_constant (XEXP (best_p->slot, 0),
732 p->align = best_p->align;
735 p->alias_set = best_p->alias_set;
736 p->next = temp_slots;
739 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
742 best_p->size = rounded_size;
743 best_p->full_size = rounded_size;
750 /* If we still didn't find one, make a new temporary. */
753 HOST_WIDE_INT frame_offset_old = frame_offset;
755 p = (struct temp_slot *) xmalloc (sizeof (struct temp_slot));
757 /* We are passing an explicit alignment request to assign_stack_local.
758 One side effect of that is assign_stack_local will not round SIZE
759 to ensure the frame offset remains suitably aligned.
761 So for requests which depended on the rounding of SIZE, we go ahead
762 and round it now. We also make sure ALIGNMENT is at least
763 BIGGEST_ALIGNMENT. */
764 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
766 p->slot = assign_stack_local (mode,
768 ? CEIL_ROUND (size, align / BITS_PER_UNIT)
773 p->alias_set = alias_set;
775 /* The following slot size computation is necessary because we don't
776 know the actual size of the temporary slot until assign_stack_local
777 has performed all the frame alignment and size rounding for the
778 requested temporary. Note that extra space added for alignment
779 can be either above or below this stack slot depending on which
780 way the frame grows. We include the extra space if and only if it
781 is above this slot. */
782 #ifdef FRAME_GROWS_DOWNWARD
783 p->size = frame_offset_old - frame_offset;
788 /* Now define the fields used by combine_temp_slots. */
789 #ifdef FRAME_GROWS_DOWNWARD
790 p->base_offset = frame_offset;
791 p->full_size = frame_offset_old - frame_offset;
793 p->base_offset = frame_offset_old;
794 p->full_size = frame_offset - frame_offset_old;
797 p->next = temp_slots;
803 p->rtl_expr = seq_rtl_expr;
807 p->level = target_temp_slot_level;
812 p->level = var_temp_slot_level;
817 p->level = temp_slot_level;
821 /* We may be reusing an old slot, so clear any MEM flags that may have been
823 RTX_UNCHANGING_P (p->slot) = 0;
824 MEM_IN_STRUCT_P (p->slot) = 0;
825 MEM_SCALAR_P (p->slot) = 0;
826 MEM_ALIAS_SET (p->slot) = alias_set;
829 MEM_SET_IN_STRUCT_P (p->slot, AGGREGATE_TYPE_P (type));
834 /* Allocate a temporary stack slot and record it for possible later
835 reuse. First three arguments are same as in preceding function. */
838 assign_stack_temp (mode, size, keep)
839 enum machine_mode mode;
843 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
846 /* Assign a temporary of given TYPE.
847 KEEP is as for assign_stack_temp.
848 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
849 it is 0 if a register is OK.
850 DONT_PROMOTE is 1 if we should not promote values in register
854 assign_temp (type, keep, memory_required, dont_promote)
858 int dont_promote ATTRIBUTE_UNUSED;
860 enum machine_mode mode = TYPE_MODE (type);
861 #ifndef PROMOTE_FOR_CALL_ONLY
862 int unsignedp = TREE_UNSIGNED (type);
865 if (mode == BLKmode || memory_required)
867 HOST_WIDE_INT size = int_size_in_bytes (type);
870 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
871 problems with allocating the stack space. */
875 /* Unfortunately, we don't yet know how to allocate variable-sized
876 temporaries. However, sometimes we have a fixed upper limit on
877 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
878 instead. This is the case for Chill variable-sized strings. */
879 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
880 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
881 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
882 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
884 tmp = assign_stack_temp_for_type (mode, size, keep, type);
888 #ifndef PROMOTE_FOR_CALL_ONLY
890 mode = promote_mode (type, mode, &unsignedp, 0);
893 return gen_reg_rtx (mode);
896 /* Combine temporary stack slots which are adjacent on the stack.
898 This allows for better use of already allocated stack space. This is only
899 done for BLKmode slots because we can be sure that we won't have alignment
900 problems in this case. */
903 combine_temp_slots ()
905 struct temp_slot *p, *q;
906 struct temp_slot *prev_p, *prev_q;
909 /* We can't combine slots, because the information about which slot
910 is in which alias set will be lost. */
911 if (flag_strict_aliasing)
914 /* If there are a lot of temp slots, don't do anything unless
915 high levels of optimizaton. */
916 if (! flag_expensive_optimizations)
917 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
918 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
921 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
925 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
926 for (q = p->next, prev_q = p; q; q = prev_q->next)
929 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
931 if (p->base_offset + p->full_size == q->base_offset)
933 /* Q comes after P; combine Q into P. */
935 p->full_size += q->full_size;
938 else if (q->base_offset + q->full_size == p->base_offset)
940 /* P comes after Q; combine P into Q. */
942 q->full_size += p->full_size;
947 /* Either delete Q or advance past it. */
950 prev_q->next = q->next;
956 /* Either delete P or advance past it. */
960 prev_p->next = p->next;
962 temp_slots = p->next;
969 /* Find the temp slot corresponding to the object at address X. */
971 static struct temp_slot *
972 find_temp_slot_from_address (x)
978 for (p = temp_slots; p; p = p->next)
983 else if (XEXP (p->slot, 0) == x
985 || (GET_CODE (x) == PLUS
986 && XEXP (x, 0) == virtual_stack_vars_rtx
987 && GET_CODE (XEXP (x, 1)) == CONST_INT
988 && INTVAL (XEXP (x, 1)) >= p->base_offset
989 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
992 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
993 for (next = p->address; next; next = XEXP (next, 1))
994 if (XEXP (next, 0) == x)
998 /* If we have a sum involving a register, see if it points to a temp
1000 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == REG
1001 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
1003 else if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == REG
1004 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
1010 /* Indicate that NEW is an alternate way of referring to the temp slot
1011 that previously was known by OLD. */
1014 update_temp_slot_address (old, new)
1017 struct temp_slot *p;
1019 if (rtx_equal_p (old, new))
1022 p = find_temp_slot_from_address (old);
1024 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
1025 is a register, see if one operand of the PLUS is a temporary
1026 location. If so, NEW points into it. Otherwise, if both OLD and
1027 NEW are a PLUS and if there is a register in common between them.
1028 If so, try a recursive call on those values. */
1031 if (GET_CODE (old) != PLUS)
1034 if (GET_CODE (new) == REG)
1036 update_temp_slot_address (XEXP (old, 0), new);
1037 update_temp_slot_address (XEXP (old, 1), new);
1040 else if (GET_CODE (new) != PLUS)
1043 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
1044 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
1045 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
1046 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
1047 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
1048 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
1049 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
1050 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
1055 /* Otherwise add an alias for the temp's address. */
1056 else if (p->address == 0)
1060 if (GET_CODE (p->address) != EXPR_LIST)
1061 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1063 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1067 /* If X could be a reference to a temporary slot, mark the fact that its
1068 address was taken. */
1071 mark_temp_addr_taken (x)
1074 struct temp_slot *p;
1079 /* If X is not in memory or is at a constant address, it cannot be in
1080 a temporary slot. */
1081 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1084 p = find_temp_slot_from_address (XEXP (x, 0));
1089 /* If X could be a reference to a temporary slot, mark that slot as
1090 belonging to the to one level higher than the current level. If X
1091 matched one of our slots, just mark that one. Otherwise, we can't
1092 easily predict which it is, so upgrade all of them. Kept slots
1093 need not be touched.
1095 This is called when an ({...}) construct occurs and a statement
1096 returns a value in memory. */
1099 preserve_temp_slots (x)
1102 struct temp_slot *p = 0;
1104 /* If there is no result, we still might have some objects whose address
1105 were taken, so we need to make sure they stay around. */
1108 for (p = temp_slots; p; p = p->next)
1109 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1115 /* If X is a register that is being used as a pointer, see if we have
1116 a temporary slot we know it points to. To be consistent with
1117 the code below, we really should preserve all non-kept slots
1118 if we can't find a match, but that seems to be much too costly. */
1119 if (GET_CODE (x) == REG && REGNO_POINTER_FLAG (REGNO (x)))
1120 p = find_temp_slot_from_address (x);
1122 /* If X is not in memory or is at a constant address, it cannot be in
1123 a temporary slot, but it can contain something whose address was
1125 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1127 for (p = temp_slots; p; p = p->next)
1128 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1134 /* First see if we can find a match. */
1136 p = find_temp_slot_from_address (XEXP (x, 0));
1140 /* Move everything at our level whose address was taken to our new
1141 level in case we used its address. */
1142 struct temp_slot *q;
1144 if (p->level == temp_slot_level)
1146 for (q = temp_slots; q; q = q->next)
1147 if (q != p && q->addr_taken && q->level == p->level)
1156 /* Otherwise, preserve all non-kept slots at this level. */
1157 for (p = temp_slots; p; p = p->next)
1158 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1162 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1163 with that RTL_EXPR, promote it into a temporary slot at the present
1164 level so it will not be freed when we free slots made in the
1168 preserve_rtl_expr_result (x)
1171 struct temp_slot *p;
1173 /* If X is not in memory or is at a constant address, it cannot be in
1174 a temporary slot. */
1175 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1178 /* If we can find a match, move it to our level unless it is already at
1180 p = find_temp_slot_from_address (XEXP (x, 0));
1183 p->level = MIN (p->level, temp_slot_level);
1190 /* Free all temporaries used so far. This is normally called at the end
1191 of generating code for a statement. Don't free any temporaries
1192 currently in use for an RTL_EXPR that hasn't yet been emitted.
1193 We could eventually do better than this since it can be reused while
1194 generating the same RTL_EXPR, but this is complex and probably not
1200 struct temp_slot *p;
1202 for (p = temp_slots; p; p = p->next)
1203 if (p->in_use && p->level == temp_slot_level && ! p->keep
1204 && p->rtl_expr == 0)
1207 combine_temp_slots ();
1210 /* Free all temporary slots used in T, an RTL_EXPR node. */
1213 free_temps_for_rtl_expr (t)
1216 struct temp_slot *p;
1218 for (p = temp_slots; p; p = p->next)
1219 if (p->rtl_expr == t)
1221 /* If this slot is below the current TEMP_SLOT_LEVEL, then it
1222 needs to be preserved. This can happen if a temporary in
1223 the RTL_EXPR was addressed; preserve_temp_slots will move
1224 the temporary into a higher level. */
1225 if (temp_slot_level <= p->level)
1228 p->rtl_expr = NULL_TREE;
1231 combine_temp_slots ();
1234 /* Mark all temporaries ever allocated in this function as not suitable
1235 for reuse until the current level is exited. */
1238 mark_all_temps_used ()
1240 struct temp_slot *p;
1242 for (p = temp_slots; p; p = p->next)
1244 p->in_use = p->keep = 1;
1245 p->level = MIN (p->level, temp_slot_level);
1249 /* Push deeper into the nesting level for stack temporaries. */
1257 /* Likewise, but save the new level as the place to allocate variables
1262 push_temp_slots_for_block ()
1266 var_temp_slot_level = temp_slot_level;
1269 /* Likewise, but save the new level as the place to allocate temporaries
1270 for TARGET_EXPRs. */
1273 push_temp_slots_for_target ()
1277 target_temp_slot_level = temp_slot_level;
1280 /* Set and get the value of target_temp_slot_level. The only
1281 permitted use of these functions is to save and restore this value. */
1284 get_target_temp_slot_level ()
1286 return target_temp_slot_level;
1290 set_target_temp_slot_level (level)
1293 target_temp_slot_level = level;
1297 /* Pop a temporary nesting level. All slots in use in the current level
1303 struct temp_slot *p;
1305 for (p = temp_slots; p; p = p->next)
1306 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1309 combine_temp_slots ();
1314 /* Initialize temporary slots. */
1319 /* We have not allocated any temporaries yet. */
1321 temp_slot_level = 0;
1322 var_temp_slot_level = 0;
1323 target_temp_slot_level = 0;
1326 /* Retroactively move an auto variable from a register to a stack slot.
1327 This is done when an address-reference to the variable is seen. */
1330 put_var_into_stack (decl)
1334 enum machine_mode promoted_mode, decl_mode;
1335 struct function *function = 0;
1337 int can_use_addressof;
1338 int volatilep = TREE_CODE (decl) != SAVE_EXPR && TREE_THIS_VOLATILE (decl);
1339 int usedp = (TREE_USED (decl)
1340 || (TREE_CODE (decl) != SAVE_EXPR && DECL_INITIAL (decl) != 0));
1342 context = decl_function_context (decl);
1344 /* Get the current rtl used for this object and its original mode. */
1345 reg = TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl) : DECL_RTL (decl);
1347 /* No need to do anything if decl has no rtx yet
1348 since in that case caller is setting TREE_ADDRESSABLE
1349 and a stack slot will be assigned when the rtl is made. */
1353 /* Get the declared mode for this object. */
1354 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1355 : DECL_MODE (decl));
1356 /* Get the mode it's actually stored in. */
1357 promoted_mode = GET_MODE (reg);
1359 /* If this variable comes from an outer function,
1360 find that function's saved context. */
1361 if (context != current_function_decl && context != inline_function_decl)
1362 for (function = outer_function_chain; function; function = function->next)
1363 if (function->decl == context)
1366 /* If this is a variable-size object with a pseudo to address it,
1367 put that pseudo into the stack, if the var is nonlocal. */
1368 if (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl)
1369 && GET_CODE (reg) == MEM
1370 && GET_CODE (XEXP (reg, 0)) == REG
1371 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1373 reg = XEXP (reg, 0);
1374 decl_mode = promoted_mode = GET_MODE (reg);
1380 /* FIXME make it work for promoted modes too */
1381 && decl_mode == promoted_mode
1382 #ifdef NON_SAVING_SETJMP
1383 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1387 /* If we can't use ADDRESSOF, make sure we see through one we already
1389 if (! can_use_addressof && GET_CODE (reg) == MEM
1390 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1391 reg = XEXP (XEXP (reg, 0), 0);
1393 /* Now we should have a value that resides in one or more pseudo regs. */
1395 if (GET_CODE (reg) == REG)
1397 /* If this variable lives in the current function and we don't need
1398 to put things in the stack for the sake of setjmp, try to keep it
1399 in a register until we know we actually need the address. */
1400 if (can_use_addressof)
1401 gen_mem_addressof (reg, decl);
1403 put_reg_into_stack (function, reg, TREE_TYPE (decl), promoted_mode,
1404 decl_mode, volatilep, 0, usedp, 0);
1406 else if (GET_CODE (reg) == CONCAT)
1408 /* A CONCAT contains two pseudos; put them both in the stack.
1409 We do it so they end up consecutive. */
1410 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1411 tree part_type = type_for_mode (part_mode, 0);
1412 #ifdef FRAME_GROWS_DOWNWARD
1413 /* Since part 0 should have a lower address, do it second. */
1414 put_reg_into_stack (function, XEXP (reg, 1), part_type, part_mode,
1415 part_mode, volatilep, 0, usedp, 0);
1416 put_reg_into_stack (function, XEXP (reg, 0), part_type, part_mode,
1417 part_mode, volatilep, 0, usedp, 0);
1419 put_reg_into_stack (function, XEXP (reg, 0), part_type, part_mode,
1420 part_mode, volatilep, 0, usedp, 0);
1421 put_reg_into_stack (function, XEXP (reg, 1), part_type, part_mode,
1422 part_mode, volatilep, 0, usedp, 0);
1425 /* Change the CONCAT into a combined MEM for both parts. */
1426 PUT_CODE (reg, MEM);
1427 set_mem_attributes (reg, decl, 1);
1429 /* The two parts are in memory order already.
1430 Use the lower parts address as ours. */
1431 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1432 /* Prevent sharing of rtl that might lose. */
1433 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1434 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1439 if (current_function_check_memory_usage)
1440 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
1441 XEXP (reg, 0), Pmode,
1442 GEN_INT (GET_MODE_SIZE (GET_MODE (reg))),
1443 TYPE_MODE (sizetype),
1444 GEN_INT (MEMORY_USE_RW),
1445 TYPE_MODE (integer_type_node));
1448 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1449 into the stack frame of FUNCTION (0 means the current function).
1450 DECL_MODE is the machine mode of the user-level data type.
1451 PROMOTED_MODE is the machine mode of the register.
1452 VOLATILE_P is nonzero if this is for a "volatile" decl.
1453 USED_P is nonzero if this reg might have already been used in an insn. */
1456 put_reg_into_stack (function, reg, type, promoted_mode, decl_mode, volatile_p,
1457 original_regno, used_p, ht)
1458 struct function *function;
1461 enum machine_mode promoted_mode, decl_mode;
1463 unsigned int original_regno;
1465 struct hash_table *ht;
1467 struct function *func = function ? function : cfun;
1469 unsigned int regno = original_regno;
1472 regno = REGNO (reg);
1474 if (regno < func->x_max_parm_reg)
1475 new = func->x_parm_reg_stack_loc[regno];
1478 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode), 0, func);
1480 PUT_CODE (reg, MEM);
1481 PUT_MODE (reg, decl_mode);
1482 XEXP (reg, 0) = XEXP (new, 0);
1483 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1484 MEM_VOLATILE_P (reg) = volatile_p;
1486 /* If this is a memory ref that contains aggregate components,
1487 mark it as such for cse and loop optimize. If we are reusing a
1488 previously generated stack slot, then we need to copy the bit in
1489 case it was set for other reasons. For instance, it is set for
1490 __builtin_va_alist. */
1491 MEM_SET_IN_STRUCT_P (reg,
1492 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1493 MEM_ALIAS_SET (reg) = get_alias_set (type);
1495 /* Now make sure that all refs to the variable, previously made
1496 when it was a register, are fixed up to be valid again. */
1498 if (used_p && function != 0)
1500 struct var_refs_queue *temp;
1503 = (struct var_refs_queue *) xmalloc (sizeof (struct var_refs_queue));
1504 temp->modified = reg;
1505 temp->promoted_mode = promoted_mode;
1506 temp->unsignedp = TREE_UNSIGNED (type);
1507 temp->next = function->fixup_var_refs_queue;
1508 function->fixup_var_refs_queue = temp;
1511 /* Variable is local; fix it up now. */
1512 fixup_var_refs (reg, promoted_mode, TREE_UNSIGNED (type), ht);
1516 fixup_var_refs (var, promoted_mode, unsignedp, ht)
1518 enum machine_mode promoted_mode;
1520 struct hash_table *ht;
1523 rtx first_insn = get_insns ();
1524 struct sequence_stack *stack = seq_stack;
1525 tree rtl_exps = rtl_expr_chain;
1528 /* Must scan all insns for stack-refs that exceed the limit. */
1529 fixup_var_refs_insns (var, promoted_mode, unsignedp, first_insn,
1531 /* If there's a hash table, it must record all uses of VAR. */
1535 /* Scan all pending sequences too. */
1536 for (; stack; stack = stack->next)
1538 push_to_sequence (stack->first);
1539 fixup_var_refs_insns (var, promoted_mode, unsignedp,
1540 stack->first, stack->next != 0, 0);
1541 /* Update remembered end of sequence
1542 in case we added an insn at the end. */
1543 stack->last = get_last_insn ();
1547 /* Scan all waiting RTL_EXPRs too. */
1548 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1550 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1551 if (seq != const0_rtx && seq != 0)
1553 push_to_sequence (seq);
1554 fixup_var_refs_insns (var, promoted_mode, unsignedp, seq, 0,
1560 /* Scan the catch clauses for exception handling too. */
1561 push_to_full_sequence (catch_clauses, catch_clauses_last);
1562 fixup_var_refs_insns (var, promoted_mode, unsignedp, catch_clauses,
1564 end_full_sequence (&catch_clauses, &catch_clauses_last);
1566 /* Scan sequences saved in CALL_PLACEHOLDERS too. */
1567 for (insn = first_insn; insn; insn = NEXT_INSN (insn))
1569 if (GET_CODE (insn) == CALL_INSN
1570 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
1574 /* Look at the Normal call, sibling call and tail recursion
1575 sequences attached to the CALL_PLACEHOLDER. */
1576 for (i = 0; i < 3; i++)
1578 rtx seq = XEXP (PATTERN (insn), i);
1581 push_to_sequence (seq);
1582 fixup_var_refs_insns (var, promoted_mode, unsignedp,
1584 XEXP (PATTERN (insn), i) = get_insns ();
1592 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1593 some part of an insn. Return a struct fixup_replacement whose OLD
1594 value is equal to X. Allocate a new structure if no such entry exists. */
1596 static struct fixup_replacement *
1597 find_fixup_replacement (replacements, x)
1598 struct fixup_replacement **replacements;
1601 struct fixup_replacement *p;
1603 /* See if we have already replaced this. */
1604 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1609 p = (struct fixup_replacement *) oballoc (sizeof (struct fixup_replacement));
1612 p->next = *replacements;
1619 /* Scan the insn-chain starting with INSN for refs to VAR
1620 and fix them up. TOPLEVEL is nonzero if this chain is the
1621 main chain of insns for the current function. */
1624 fixup_var_refs_insns (var, promoted_mode, unsignedp, insn, toplevel, ht)
1626 enum machine_mode promoted_mode;
1630 struct hash_table *ht;
1633 rtx insn_list = NULL_RTX;
1635 /* If we already know which INSNs reference VAR there's no need
1636 to walk the entire instruction chain. */
1639 insn_list = ((struct insns_for_mem_entry *)
1640 hash_lookup (ht, var, /*create=*/0, /*copy=*/0))->insns;
1641 insn = insn_list ? XEXP (insn_list, 0) : NULL_RTX;
1642 insn_list = XEXP (insn_list, 1);
1647 rtx next = NEXT_INSN (insn);
1648 rtx set, prev, prev_set;
1651 if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
1653 /* Remember the notes in case we delete the insn. */
1654 note = REG_NOTES (insn);
1656 /* If this is a CLOBBER of VAR, delete it.
1658 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1659 and REG_RETVAL notes too. */
1660 if (GET_CODE (PATTERN (insn)) == CLOBBER
1661 && (XEXP (PATTERN (insn), 0) == var
1662 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1663 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1664 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1666 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1667 /* The REG_LIBCALL note will go away since we are going to
1668 turn INSN into a NOTE, so just delete the
1669 corresponding REG_RETVAL note. */
1670 remove_note (XEXP (note, 0),
1671 find_reg_note (XEXP (note, 0), REG_RETVAL,
1674 /* In unoptimized compilation, we shouldn't call delete_insn
1675 except in jump.c doing warnings. */
1676 PUT_CODE (insn, NOTE);
1677 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1678 NOTE_SOURCE_FILE (insn) = 0;
1681 /* The insn to load VAR from a home in the arglist
1682 is now a no-op. When we see it, just delete it.
1683 Similarly if this is storing VAR from a register from which
1684 it was loaded in the previous insn. This will occur
1685 when an ADDRESSOF was made for an arglist slot. */
1687 && (set = single_set (insn)) != 0
1688 && SET_DEST (set) == var
1689 /* If this represents the result of an insn group,
1690 don't delete the insn. */
1691 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1692 && (rtx_equal_p (SET_SRC (set), var)
1693 || (GET_CODE (SET_SRC (set)) == REG
1694 && (prev = prev_nonnote_insn (insn)) != 0
1695 && (prev_set = single_set (prev)) != 0
1696 && SET_DEST (prev_set) == SET_SRC (set)
1697 && rtx_equal_p (SET_SRC (prev_set), var))))
1699 /* In unoptimized compilation, we shouldn't call delete_insn
1700 except in jump.c doing warnings. */
1701 PUT_CODE (insn, NOTE);
1702 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1703 NOTE_SOURCE_FILE (insn) = 0;
1704 if (insn == last_parm_insn)
1705 last_parm_insn = PREV_INSN (next);
1709 struct fixup_replacement *replacements = 0;
1710 rtx next_insn = NEXT_INSN (insn);
1712 if (SMALL_REGISTER_CLASSES)
1714 /* If the insn that copies the results of a CALL_INSN
1715 into a pseudo now references VAR, we have to use an
1716 intermediate pseudo since we want the life of the
1717 return value register to be only a single insn.
1719 If we don't use an intermediate pseudo, such things as
1720 address computations to make the address of VAR valid
1721 if it is not can be placed between the CALL_INSN and INSN.
1723 To make sure this doesn't happen, we record the destination
1724 of the CALL_INSN and see if the next insn uses both that
1727 if (call_dest != 0 && GET_CODE (insn) == INSN
1728 && reg_mentioned_p (var, PATTERN (insn))
1729 && reg_mentioned_p (call_dest, PATTERN (insn)))
1731 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1733 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1735 PATTERN (insn) = replace_rtx (PATTERN (insn),
1739 if (GET_CODE (insn) == CALL_INSN
1740 && GET_CODE (PATTERN (insn)) == SET)
1741 call_dest = SET_DEST (PATTERN (insn));
1742 else if (GET_CODE (insn) == CALL_INSN
1743 && GET_CODE (PATTERN (insn)) == PARALLEL
1744 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1745 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1750 /* See if we have to do anything to INSN now that VAR is in
1751 memory. If it needs to be loaded into a pseudo, use a single
1752 pseudo for the entire insn in case there is a MATCH_DUP
1753 between two operands. We pass a pointer to the head of
1754 a list of struct fixup_replacements. If fixup_var_refs_1
1755 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1756 it will record them in this list.
1758 If it allocated a pseudo for any replacement, we copy into
1761 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1764 /* If this is last_parm_insn, and any instructions were output
1765 after it to fix it up, then we must set last_parm_insn to
1766 the last such instruction emitted. */
1767 if (insn == last_parm_insn)
1768 last_parm_insn = PREV_INSN (next_insn);
1770 while (replacements)
1772 if (GET_CODE (replacements->new) == REG)
1777 /* OLD might be a (subreg (mem)). */
1778 if (GET_CODE (replacements->old) == SUBREG)
1780 = fixup_memory_subreg (replacements->old, insn, 0);
1783 = fixup_stack_1 (replacements->old, insn);
1785 insert_before = insn;
1787 /* If we are changing the mode, do a conversion.
1788 This might be wasteful, but combine.c will
1789 eliminate much of the waste. */
1791 if (GET_MODE (replacements->new)
1792 != GET_MODE (replacements->old))
1795 convert_move (replacements->new,
1796 replacements->old, unsignedp);
1797 seq = gen_sequence ();
1801 seq = gen_move_insn (replacements->new,
1804 emit_insn_before (seq, insert_before);
1807 replacements = replacements->next;
1811 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1812 But don't touch other insns referred to by reg-notes;
1813 we will get them elsewhere. */
1816 if (GET_CODE (note) != INSN_LIST)
1818 = walk_fixup_memory_subreg (XEXP (note, 0), insn, 1);
1819 note = XEXP (note, 1);
1827 insn = XEXP (insn_list, 0);
1828 insn_list = XEXP (insn_list, 1);
1835 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1836 See if the rtx expression at *LOC in INSN needs to be changed.
1838 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1839 contain a list of original rtx's and replacements. If we find that we need
1840 to modify this insn by replacing a memory reference with a pseudo or by
1841 making a new MEM to implement a SUBREG, we consult that list to see if
1842 we have already chosen a replacement. If none has already been allocated,
1843 we allocate it and update the list. fixup_var_refs_insns will copy VAR
1844 or the SUBREG, as appropriate, to the pseudo. */
1847 fixup_var_refs_1 (var, promoted_mode, loc, insn, replacements)
1849 enum machine_mode promoted_mode;
1852 struct fixup_replacement **replacements;
1855 register rtx x = *loc;
1856 RTX_CODE code = GET_CODE (x);
1857 register const char *fmt;
1858 register rtx tem, tem1;
1859 struct fixup_replacement *replacement;
1864 if (XEXP (x, 0) == var)
1866 /* Prevent sharing of rtl that might lose. */
1867 rtx sub = copy_rtx (XEXP (var, 0));
1869 if (! validate_change (insn, loc, sub, 0))
1871 rtx y = gen_reg_rtx (GET_MODE (sub));
1874 /* We should be able to replace with a register or all is lost.
1875 Note that we can't use validate_change to verify this, since
1876 we're not caring for replacing all dups simultaneously. */
1877 if (! validate_replace_rtx (*loc, y, insn))
1880 /* Careful! First try to recognize a direct move of the
1881 value, mimicking how things are done in gen_reload wrt
1882 PLUS. Consider what happens when insn is a conditional
1883 move instruction and addsi3 clobbers flags. */
1886 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1887 seq = gen_sequence ();
1890 if (recog_memoized (new_insn) < 0)
1892 /* That failed. Fall back on force_operand and hope. */
1895 force_operand (sub, y);
1896 seq = gen_sequence ();
1901 /* Don't separate setter from user. */
1902 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1903 insn = PREV_INSN (insn);
1906 emit_insn_before (seq, insn);
1914 /* If we already have a replacement, use it. Otherwise,
1915 try to fix up this address in case it is invalid. */
1917 replacement = find_fixup_replacement (replacements, var);
1918 if (replacement->new)
1920 *loc = replacement->new;
1924 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1926 /* Unless we are forcing memory to register or we changed the mode,
1927 we can leave things the way they are if the insn is valid. */
1929 INSN_CODE (insn) = -1;
1930 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1931 && recog_memoized (insn) >= 0)
1934 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1938 /* If X contains VAR, we need to unshare it here so that we update
1939 each occurrence separately. But all identical MEMs in one insn
1940 must be replaced with the same rtx because of the possibility of
1943 if (reg_mentioned_p (var, x))
1945 replacement = find_fixup_replacement (replacements, x);
1946 if (replacement->new == 0)
1947 replacement->new = copy_most_rtx (x, var);
1949 *loc = x = replacement->new;
1965 /* Note that in some cases those types of expressions are altered
1966 by optimize_bit_field, and do not survive to get here. */
1967 if (XEXP (x, 0) == var
1968 || (GET_CODE (XEXP (x, 0)) == SUBREG
1969 && SUBREG_REG (XEXP (x, 0)) == var))
1971 /* Get TEM as a valid MEM in the mode presently in the insn.
1973 We don't worry about the possibility of MATCH_DUP here; it
1974 is highly unlikely and would be tricky to handle. */
1977 if (GET_CODE (tem) == SUBREG)
1979 if (GET_MODE_BITSIZE (GET_MODE (tem))
1980 > GET_MODE_BITSIZE (GET_MODE (var)))
1982 replacement = find_fixup_replacement (replacements, var);
1983 if (replacement->new == 0)
1984 replacement->new = gen_reg_rtx (GET_MODE (var));
1985 SUBREG_REG (tem) = replacement->new;
1988 tem = fixup_memory_subreg (tem, insn, 0);
1991 tem = fixup_stack_1 (tem, insn);
1993 /* Unless we want to load from memory, get TEM into the proper mode
1994 for an extract from memory. This can only be done if the
1995 extract is at a constant position and length. */
1997 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
1998 && GET_CODE (XEXP (x, 2)) == CONST_INT
1999 && ! mode_dependent_address_p (XEXP (tem, 0))
2000 && ! MEM_VOLATILE_P (tem))
2002 enum machine_mode wanted_mode = VOIDmode;
2003 enum machine_mode is_mode = GET_MODE (tem);
2004 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
2007 if (GET_CODE (x) == ZERO_EXTRACT)
2010 = insn_data[(int) CODE_FOR_extzv].operand[1].mode;
2011 if (wanted_mode == VOIDmode)
2012 wanted_mode = word_mode;
2016 if (GET_CODE (x) == SIGN_EXTRACT)
2018 wanted_mode = insn_data[(int) CODE_FOR_extv].operand[1].mode;
2019 if (wanted_mode == VOIDmode)
2020 wanted_mode = word_mode;
2023 /* If we have a narrower mode, we can do something. */
2024 if (wanted_mode != VOIDmode
2025 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2027 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2028 rtx old_pos = XEXP (x, 2);
2031 /* If the bytes and bits are counted differently, we
2032 must adjust the offset. */
2033 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2034 offset = (GET_MODE_SIZE (is_mode)
2035 - GET_MODE_SIZE (wanted_mode) - offset);
2037 pos %= GET_MODE_BITSIZE (wanted_mode);
2039 newmem = gen_rtx_MEM (wanted_mode,
2040 plus_constant (XEXP (tem, 0), offset));
2041 MEM_COPY_ATTRIBUTES (newmem, tem);
2043 /* Make the change and see if the insn remains valid. */
2044 INSN_CODE (insn) = -1;
2045 XEXP (x, 0) = newmem;
2046 XEXP (x, 2) = GEN_INT (pos);
2048 if (recog_memoized (insn) >= 0)
2051 /* Otherwise, restore old position. XEXP (x, 0) will be
2053 XEXP (x, 2) = old_pos;
2057 /* If we get here, the bitfield extract insn can't accept a memory
2058 reference. Copy the input into a register. */
2060 tem1 = gen_reg_rtx (GET_MODE (tem));
2061 emit_insn_before (gen_move_insn (tem1, tem), insn);
2068 if (SUBREG_REG (x) == var)
2070 /* If this is a special SUBREG made because VAR was promoted
2071 from a wider mode, replace it with VAR and call ourself
2072 recursively, this time saying that the object previously
2073 had its current mode (by virtue of the SUBREG). */
2075 if (SUBREG_PROMOTED_VAR_P (x))
2078 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements);
2082 /* If this SUBREG makes VAR wider, it has become a paradoxical
2083 SUBREG with VAR in memory, but these aren't allowed at this
2084 stage of the compilation. So load VAR into a pseudo and take
2085 a SUBREG of that pseudo. */
2086 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2088 replacement = find_fixup_replacement (replacements, var);
2089 if (replacement->new == 0)
2090 replacement->new = gen_reg_rtx (GET_MODE (var));
2091 SUBREG_REG (x) = replacement->new;
2095 /* See if we have already found a replacement for this SUBREG.
2096 If so, use it. Otherwise, make a MEM and see if the insn
2097 is recognized. If not, or if we should force MEM into a register,
2098 make a pseudo for this SUBREG. */
2099 replacement = find_fixup_replacement (replacements, x);
2100 if (replacement->new)
2102 *loc = replacement->new;
2106 replacement->new = *loc = fixup_memory_subreg (x, insn, 0);
2108 INSN_CODE (insn) = -1;
2109 if (! flag_force_mem && recog_memoized (insn) >= 0)
2112 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2118 /* First do special simplification of bit-field references. */
2119 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2120 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2121 optimize_bit_field (x, insn, 0);
2122 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2123 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2124 optimize_bit_field (x, insn, NULL_PTR);
2126 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2127 into a register and then store it back out. */
2128 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2129 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2130 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2131 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2132 > GET_MODE_SIZE (GET_MODE (var))))
2134 replacement = find_fixup_replacement (replacements, var);
2135 if (replacement->new == 0)
2136 replacement->new = gen_reg_rtx (GET_MODE (var));
2138 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2139 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2142 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2143 insn into a pseudo and store the low part of the pseudo into VAR. */
2144 if (GET_CODE (SET_DEST (x)) == SUBREG
2145 && SUBREG_REG (SET_DEST (x)) == var
2146 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2147 > GET_MODE_SIZE (GET_MODE (var))))
2149 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2150 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2157 rtx dest = SET_DEST (x);
2158 rtx src = SET_SRC (x);
2160 rtx outerdest = dest;
2163 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2164 || GET_CODE (dest) == SIGN_EXTRACT
2165 || GET_CODE (dest) == ZERO_EXTRACT)
2166 dest = XEXP (dest, 0);
2168 if (GET_CODE (src) == SUBREG)
2169 src = XEXP (src, 0);
2171 /* If VAR does not appear at the top level of the SET
2172 just scan the lower levels of the tree. */
2174 if (src != var && dest != var)
2177 /* We will need to rerecognize this insn. */
2178 INSN_CODE (insn) = -1;
2181 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var)
2183 /* Since this case will return, ensure we fixup all the
2185 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2186 insn, replacements);
2187 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2188 insn, replacements);
2189 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2190 insn, replacements);
2192 tem = XEXP (outerdest, 0);
2194 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2195 that may appear inside a ZERO_EXTRACT.
2196 This was legitimate when the MEM was a REG. */
2197 if (GET_CODE (tem) == SUBREG
2198 && SUBREG_REG (tem) == var)
2199 tem = fixup_memory_subreg (tem, insn, 0);
2201 tem = fixup_stack_1 (tem, insn);
2203 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2204 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2205 && ! mode_dependent_address_p (XEXP (tem, 0))
2206 && ! MEM_VOLATILE_P (tem))
2208 enum machine_mode wanted_mode;
2209 enum machine_mode is_mode = GET_MODE (tem);
2210 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2212 wanted_mode = insn_data[(int) CODE_FOR_insv].operand[0].mode;
2213 if (wanted_mode == VOIDmode)
2214 wanted_mode = word_mode;
2216 /* If we have a narrower mode, we can do something. */
2217 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2219 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2220 rtx old_pos = XEXP (outerdest, 2);
2223 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2224 offset = (GET_MODE_SIZE (is_mode)
2225 - GET_MODE_SIZE (wanted_mode) - offset);
2227 pos %= GET_MODE_BITSIZE (wanted_mode);
2229 newmem = gen_rtx_MEM (wanted_mode,
2230 plus_constant (XEXP (tem, 0),
2232 MEM_COPY_ATTRIBUTES (newmem, tem);
2234 /* Make the change and see if the insn remains valid. */
2235 INSN_CODE (insn) = -1;
2236 XEXP (outerdest, 0) = newmem;
2237 XEXP (outerdest, 2) = GEN_INT (pos);
2239 if (recog_memoized (insn) >= 0)
2242 /* Otherwise, restore old position. XEXP (x, 0) will be
2244 XEXP (outerdest, 2) = old_pos;
2248 /* If we get here, the bit-field store doesn't allow memory
2249 or isn't located at a constant position. Load the value into
2250 a register, do the store, and put it back into memory. */
2252 tem1 = gen_reg_rtx (GET_MODE (tem));
2253 emit_insn_before (gen_move_insn (tem1, tem), insn);
2254 emit_insn_after (gen_move_insn (tem, tem1), insn);
2255 XEXP (outerdest, 0) = tem1;
2260 /* STRICT_LOW_PART is a no-op on memory references
2261 and it can cause combinations to be unrecognizable,
2264 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2265 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2267 /* A valid insn to copy VAR into or out of a register
2268 must be left alone, to avoid an infinite loop here.
2269 If the reference to VAR is by a subreg, fix that up,
2270 since SUBREG is not valid for a memref.
2271 Also fix up the address of the stack slot.
2273 Note that we must not try to recognize the insn until
2274 after we know that we have valid addresses and no
2275 (subreg (mem ...) ...) constructs, since these interfere
2276 with determining the validity of the insn. */
2278 if ((SET_SRC (x) == var
2279 || (GET_CODE (SET_SRC (x)) == SUBREG
2280 && SUBREG_REG (SET_SRC (x)) == var))
2281 && (GET_CODE (SET_DEST (x)) == REG
2282 || (GET_CODE (SET_DEST (x)) == SUBREG
2283 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2284 && GET_MODE (var) == promoted_mode
2285 && x == single_set (insn))
2289 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2290 if (replacement->new)
2291 SET_SRC (x) = replacement->new;
2292 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2293 SET_SRC (x) = replacement->new
2294 = fixup_memory_subreg (SET_SRC (x), insn, 0);
2296 SET_SRC (x) = replacement->new
2297 = fixup_stack_1 (SET_SRC (x), insn);
2299 if (recog_memoized (insn) >= 0)
2302 /* INSN is not valid, but we know that we want to
2303 copy SET_SRC (x) to SET_DEST (x) in some way. So
2304 we generate the move and see whether it requires more
2305 than one insn. If it does, we emit those insns and
2306 delete INSN. Otherwise, we an just replace the pattern
2307 of INSN; we have already verified above that INSN has
2308 no other function that to do X. */
2310 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2311 if (GET_CODE (pat) == SEQUENCE)
2313 emit_insn_after (pat, insn);
2314 PUT_CODE (insn, NOTE);
2315 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
2316 NOTE_SOURCE_FILE (insn) = 0;
2319 PATTERN (insn) = pat;
2324 if ((SET_DEST (x) == var
2325 || (GET_CODE (SET_DEST (x)) == SUBREG
2326 && SUBREG_REG (SET_DEST (x)) == var))
2327 && (GET_CODE (SET_SRC (x)) == REG
2328 || (GET_CODE (SET_SRC (x)) == SUBREG
2329 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2330 && GET_MODE (var) == promoted_mode
2331 && x == single_set (insn))
2335 if (GET_CODE (SET_DEST (x)) == SUBREG)
2336 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn, 0);
2338 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2340 if (recog_memoized (insn) >= 0)
2343 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2344 if (GET_CODE (pat) == SEQUENCE)
2346 emit_insn_after (pat, insn);
2347 PUT_CODE (insn, NOTE);
2348 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
2349 NOTE_SOURCE_FILE (insn) = 0;
2352 PATTERN (insn) = pat;
2357 /* Otherwise, storing into VAR must be handled specially
2358 by storing into a temporary and copying that into VAR
2359 with a new insn after this one. Note that this case
2360 will be used when storing into a promoted scalar since
2361 the insn will now have different modes on the input
2362 and output and hence will be invalid (except for the case
2363 of setting it to a constant, which does not need any
2364 change if it is valid). We generate extra code in that case,
2365 but combine.c will eliminate it. */
2370 rtx fixeddest = SET_DEST (x);
2372 /* STRICT_LOW_PART can be discarded, around a MEM. */
2373 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2374 fixeddest = XEXP (fixeddest, 0);
2375 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2376 if (GET_CODE (fixeddest) == SUBREG)
2378 fixeddest = fixup_memory_subreg (fixeddest, insn, 0);
2379 promoted_mode = GET_MODE (fixeddest);
2382 fixeddest = fixup_stack_1 (fixeddest, insn);
2384 temp = gen_reg_rtx (promoted_mode);
2386 emit_insn_after (gen_move_insn (fixeddest,
2387 gen_lowpart (GET_MODE (fixeddest),
2391 SET_DEST (x) = temp;
2399 /* Nothing special about this RTX; fix its operands. */
2401 fmt = GET_RTX_FORMAT (code);
2402 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2405 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements);
2406 else if (fmt[i] == 'E')
2409 for (j = 0; j < XVECLEN (x, i); j++)
2410 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2411 insn, replacements);
2416 /* Given X, an rtx of the form (SUBREG:m1 (MEM:m2 addr)),
2417 return an rtx (MEM:m1 newaddr) which is equivalent.
2418 If any insns must be emitted to compute NEWADDR, put them before INSN.
2420 UNCRITICAL nonzero means accept paradoxical subregs.
2421 This is used for subregs found inside REG_NOTES. */
2424 fixup_memory_subreg (x, insn, uncritical)
2429 int offset = SUBREG_WORD (x) * UNITS_PER_WORD;
2430 rtx addr = XEXP (SUBREG_REG (x), 0);
2431 enum machine_mode mode = GET_MODE (x);
2434 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2435 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))
2439 if (BYTES_BIG_ENDIAN)
2440 offset += (MIN (UNITS_PER_WORD, GET_MODE_SIZE (GET_MODE (SUBREG_REG (x))))
2441 - MIN (UNITS_PER_WORD, GET_MODE_SIZE (mode)));
2442 addr = plus_constant (addr, offset);
2443 if (!flag_force_addr && memory_address_p (mode, addr))
2444 /* Shortcut if no insns need be emitted. */
2445 return change_address (SUBREG_REG (x), mode, addr);
2447 result = change_address (SUBREG_REG (x), mode, addr);
2448 emit_insn_before (gen_sequence (), insn);
2453 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2454 Replace subexpressions of X in place.
2455 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2456 Otherwise return X, with its contents possibly altered.
2458 If any insns must be emitted to compute NEWADDR, put them before INSN.
2460 UNCRITICAL is as in fixup_memory_subreg. */
2463 walk_fixup_memory_subreg (x, insn, uncritical)
2468 register enum rtx_code code;
2469 register const char *fmt;
2475 code = GET_CODE (x);
2477 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2478 return fixup_memory_subreg (x, insn, uncritical);
2480 /* Nothing special about this RTX; fix its operands. */
2482 fmt = GET_RTX_FORMAT (code);
2483 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2486 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn, uncritical);
2487 else if (fmt[i] == 'E')
2490 for (j = 0; j < XVECLEN (x, i); j++)
2492 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn, uncritical);
2498 /* For each memory ref within X, if it refers to a stack slot
2499 with an out of range displacement, put the address in a temp register
2500 (emitting new insns before INSN to load these registers)
2501 and alter the memory ref to use that register.
2502 Replace each such MEM rtx with a copy, to avoid clobberage. */
2505 fixup_stack_1 (x, insn)
2510 register RTX_CODE code = GET_CODE (x);
2511 register const char *fmt;
2515 register rtx ad = XEXP (x, 0);
2516 /* If we have address of a stack slot but it's not valid
2517 (displacement is too large), compute the sum in a register. */
2518 if (GET_CODE (ad) == PLUS
2519 && GET_CODE (XEXP (ad, 0)) == REG
2520 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2521 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2522 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2523 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2524 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2526 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2527 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2528 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2529 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2532 if (memory_address_p (GET_MODE (x), ad))
2536 temp = copy_to_reg (ad);
2537 seq = gen_sequence ();
2539 emit_insn_before (seq, insn);
2540 return change_address (x, VOIDmode, temp);
2545 fmt = GET_RTX_FORMAT (code);
2546 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2549 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2550 else if (fmt[i] == 'E')
2553 for (j = 0; j < XVECLEN (x, i); j++)
2554 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2560 /* Optimization: a bit-field instruction whose field
2561 happens to be a byte or halfword in memory
2562 can be changed to a move instruction.
2564 We call here when INSN is an insn to examine or store into a bit-field.
2565 BODY is the SET-rtx to be altered.
2567 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2568 (Currently this is called only from function.c, and EQUIV_MEM
2572 optimize_bit_field (body, insn, equiv_mem)
2577 register rtx bitfield;
2580 enum machine_mode mode;
2582 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2583 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2584 bitfield = SET_DEST (body), destflag = 1;
2586 bitfield = SET_SRC (body), destflag = 0;
2588 /* First check that the field being stored has constant size and position
2589 and is in fact a byte or halfword suitably aligned. */
2591 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2592 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2593 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2595 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2597 register rtx memref = 0;
2599 /* Now check that the containing word is memory, not a register,
2600 and that it is safe to change the machine mode. */
2602 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2603 memref = XEXP (bitfield, 0);
2604 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2606 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2607 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2608 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2609 memref = SUBREG_REG (XEXP (bitfield, 0));
2610 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2612 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2613 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2616 && ! mode_dependent_address_p (XEXP (memref, 0))
2617 && ! MEM_VOLATILE_P (memref))
2619 /* Now adjust the address, first for any subreg'ing
2620 that we are now getting rid of,
2621 and then for which byte of the word is wanted. */
2623 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2626 /* Adjust OFFSET to count bits from low-address byte. */
2627 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2628 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2629 - offset - INTVAL (XEXP (bitfield, 1)));
2631 /* Adjust OFFSET to count bytes from low-address byte. */
2632 offset /= BITS_PER_UNIT;
2633 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2635 offset += SUBREG_WORD (XEXP (bitfield, 0)) * UNITS_PER_WORD;
2636 if (BYTES_BIG_ENDIAN)
2637 offset -= (MIN (UNITS_PER_WORD,
2638 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2639 - MIN (UNITS_PER_WORD,
2640 GET_MODE_SIZE (GET_MODE (memref))));
2644 memref = change_address (memref, mode,
2645 plus_constant (XEXP (memref, 0), offset));
2646 insns = get_insns ();
2648 emit_insns_before (insns, insn);
2650 /* Store this memory reference where
2651 we found the bit field reference. */
2655 validate_change (insn, &SET_DEST (body), memref, 1);
2656 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2658 rtx src = SET_SRC (body);
2659 while (GET_CODE (src) == SUBREG
2660 && SUBREG_WORD (src) == 0)
2661 src = SUBREG_REG (src);
2662 if (GET_MODE (src) != GET_MODE (memref))
2663 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2664 validate_change (insn, &SET_SRC (body), src, 1);
2666 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2667 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2668 /* This shouldn't happen because anything that didn't have
2669 one of these modes should have got converted explicitly
2670 and then referenced through a subreg.
2671 This is so because the original bit-field was
2672 handled by agg_mode and so its tree structure had
2673 the same mode that memref now has. */
2678 rtx dest = SET_DEST (body);
2680 while (GET_CODE (dest) == SUBREG
2681 && SUBREG_WORD (dest) == 0
2682 && (GET_MODE_CLASS (GET_MODE (dest))
2683 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2684 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2686 dest = SUBREG_REG (dest);
2688 validate_change (insn, &SET_DEST (body), dest, 1);
2690 if (GET_MODE (dest) == GET_MODE (memref))
2691 validate_change (insn, &SET_SRC (body), memref, 1);
2694 /* Convert the mem ref to the destination mode. */
2695 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2698 convert_move (newreg, memref,
2699 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2703 validate_change (insn, &SET_SRC (body), newreg, 1);
2707 /* See if we can convert this extraction or insertion into
2708 a simple move insn. We might not be able to do so if this
2709 was, for example, part of a PARALLEL.
2711 If we succeed, write out any needed conversions. If we fail,
2712 it is hard to guess why we failed, so don't do anything
2713 special; just let the optimization be suppressed. */
2715 if (apply_change_group () && seq)
2716 emit_insns_before (seq, insn);
2721 /* These routines are responsible for converting virtual register references
2722 to the actual hard register references once RTL generation is complete.
2724 The following four variables are used for communication between the
2725 routines. They contain the offsets of the virtual registers from their
2726 respective hard registers. */
2728 static int in_arg_offset;
2729 static int var_offset;
2730 static int dynamic_offset;
2731 static int out_arg_offset;
2732 static int cfa_offset;
2734 /* In most machines, the stack pointer register is equivalent to the bottom
2737 #ifndef STACK_POINTER_OFFSET
2738 #define STACK_POINTER_OFFSET 0
2741 /* If not defined, pick an appropriate default for the offset of dynamically
2742 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2743 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2745 #ifndef STACK_DYNAMIC_OFFSET
2747 /* The bottom of the stack points to the actual arguments. If
2748 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2749 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2750 stack space for register parameters is not pushed by the caller, but
2751 rather part of the fixed stack areas and hence not included in
2752 `current_function_outgoing_args_size'. Nevertheless, we must allow
2753 for it when allocating stack dynamic objects. */
2755 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2756 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2757 ((ACCUMULATE_OUTGOING_ARGS \
2758 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2759 + (STACK_POINTER_OFFSET)) \
2762 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2763 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2764 + (STACK_POINTER_OFFSET))
2768 /* On most machines, the CFA coincides with the first incoming parm. */
2770 #ifndef ARG_POINTER_CFA_OFFSET
2771 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2775 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just had
2776 its address taken. DECL is the decl for the object stored in the
2777 register, for later use if we do need to force REG into the stack.
2778 REG is overwritten by the MEM like in put_reg_into_stack. */
2781 gen_mem_addressof (reg, decl)
2785 tree type = TREE_TYPE (decl);
2786 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2789 /* If the original REG was a user-variable, then so is the REG whose
2790 address is being taken. Likewise for unchanging. */
2791 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2792 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2794 PUT_CODE (reg, MEM);
2795 PUT_MODE (reg, DECL_MODE (decl));
2797 MEM_VOLATILE_P (reg) = TREE_SIDE_EFFECTS (decl);
2798 MEM_SET_IN_STRUCT_P (reg, AGGREGATE_TYPE_P (type));
2799 MEM_ALIAS_SET (reg) = get_alias_set (decl);
2801 if (TREE_USED (decl) || DECL_INITIAL (decl) != 0)
2802 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), 0);
2807 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2810 flush_addressof (decl)
2813 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2814 && DECL_RTL (decl) != 0
2815 && GET_CODE (DECL_RTL (decl)) == MEM
2816 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2817 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2818 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2821 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2824 put_addressof_into_stack (r, ht)
2826 struct hash_table *ht;
2828 tree decl = ADDRESSOF_DECL (r);
2829 rtx reg = XEXP (r, 0);
2831 if (GET_CODE (reg) != REG)
2834 put_reg_into_stack (0, reg, TREE_TYPE (decl), GET_MODE (reg),
2836 (TREE_CODE (decl) != SAVE_EXPR
2837 && TREE_THIS_VOLATILE (decl)),
2838 ADDRESSOF_REGNO (r),
2840 || (TREE_CODE (decl) != SAVE_EXPR
2841 && DECL_INITIAL (decl) != 0)),
2845 /* List of replacements made below in purge_addressof_1 when creating
2846 bitfield insertions. */
2847 static rtx purge_bitfield_addressof_replacements;
2849 /* List of replacements made below in purge_addressof_1 for patterns
2850 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2851 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2852 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2853 enough in complex cases, e.g. when some field values can be
2854 extracted by usage MEM with narrower mode. */
2855 static rtx purge_addressof_replacements;
2857 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2858 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2859 the stack. If the function returns FALSE then the replacement could not
2863 purge_addressof_1 (loc, insn, force, store, ht)
2867 struct hash_table *ht;
2873 boolean result = true;
2875 /* Re-start here to avoid recursion in common cases. */
2882 code = GET_CODE (x);
2884 /* If we don't return in any of the cases below, we will recurse inside
2885 the RTX, which will normally result in any ADDRESSOF being forced into
2889 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1, ht);
2890 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0, ht);
2894 else if (code == ADDRESSOF && GET_CODE (XEXP (x, 0)) == MEM)
2896 /* We must create a copy of the rtx because it was created by
2897 overwriting a REG rtx which is always shared. */
2898 rtx sub = copy_rtx (XEXP (XEXP (x, 0), 0));
2901 if (validate_change (insn, loc, sub, 0)
2902 || validate_replace_rtx (x, sub, insn))
2906 sub = force_operand (sub, NULL_RTX);
2907 if (! validate_change (insn, loc, sub, 0)
2908 && ! validate_replace_rtx (x, sub, insn))
2911 insns = gen_sequence ();
2913 emit_insn_before (insns, insn);
2917 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
2919 rtx sub = XEXP (XEXP (x, 0), 0);
2922 if (GET_CODE (sub) == MEM)
2924 sub2 = gen_rtx_MEM (GET_MODE (x), copy_rtx (XEXP (sub, 0)));
2925 MEM_COPY_ATTRIBUTES (sub2, sub);
2928 else if (GET_CODE (sub) == REG
2929 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
2931 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
2933 int size_x, size_sub;
2937 /* When processing REG_NOTES look at the list of
2938 replacements done on the insn to find the register that X
2942 for (tem = purge_bitfield_addressof_replacements;
2944 tem = XEXP (XEXP (tem, 1), 1))
2945 if (rtx_equal_p (x, XEXP (tem, 0)))
2947 *loc = XEXP (XEXP (tem, 1), 0);
2951 /* See comment for purge_addressof_replacements. */
2952 for (tem = purge_addressof_replacements;
2954 tem = XEXP (XEXP (tem, 1), 1))
2955 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
2957 rtx z = XEXP (XEXP (tem, 1), 0);
2959 if (GET_MODE (x) == GET_MODE (z)
2960 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
2961 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
2964 /* It can happen that the note may speak of things
2965 in a wider (or just different) mode than the
2966 code did. This is especially true of
2969 if (GET_CODE (z) == SUBREG && SUBREG_WORD (z) == 0)
2972 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
2973 && (GET_MODE_SIZE (GET_MODE (x))
2974 > GET_MODE_SIZE (GET_MODE (z))))
2976 /* This can occur as a result in invalid
2977 pointer casts, e.g. float f; ...
2978 *(long long int *)&f.
2979 ??? We could emit a warning here, but
2980 without a line number that wouldn't be
2982 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
2985 z = gen_lowpart (GET_MODE (x), z);
2991 /* Sometimes we may not be able to find the replacement. For
2992 example when the original insn was a MEM in a wider mode,
2993 and the note is part of a sign extension of a narrowed
2994 version of that MEM. Gcc testcase compile/990829-1.c can
2995 generate an example of this siutation. Rather than complain
2996 we return false, which will prompt our caller to remove the
3001 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3002 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3004 /* Don't even consider working with paradoxical subregs,
3005 or the moral equivalent seen here. */
3006 if (size_x <= size_sub
3007 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3009 /* Do a bitfield insertion to mirror what would happen
3016 rtx p = PREV_INSN (insn);
3019 val = gen_reg_rtx (GET_MODE (x));
3020 if (! validate_change (insn, loc, val, 0))
3022 /* Discard the current sequence and put the
3023 ADDRESSOF on stack. */
3027 seq = gen_sequence ();
3029 emit_insn_before (seq, insn);
3030 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3034 store_bit_field (sub, size_x, 0, GET_MODE (x),
3035 val, GET_MODE_SIZE (GET_MODE (sub)),
3036 GET_MODE_ALIGNMENT (GET_MODE (sub)));
3038 /* Make sure to unshare any shared rtl that store_bit_field
3039 might have created. */
3040 unshare_all_rtl_again (get_insns ());
3042 seq = gen_sequence ();
3044 p = emit_insn_after (seq, insn);
3045 if (NEXT_INSN (insn))
3046 compute_insns_for_mem (NEXT_INSN (insn),
3047 p ? NEXT_INSN (p) : NULL_RTX,
3052 rtx p = PREV_INSN (insn);
3055 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3056 GET_MODE (x), GET_MODE (x),
3057 GET_MODE_SIZE (GET_MODE (sub)),
3058 GET_MODE_SIZE (GET_MODE (sub)));
3060 if (! validate_change (insn, loc, val, 0))
3062 /* Discard the current sequence and put the
3063 ADDRESSOF on stack. */
3068 seq = gen_sequence ();
3070 emit_insn_before (seq, insn);
3071 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3075 /* Remember the replacement so that the same one can be done
3076 on the REG_NOTES. */
3077 purge_bitfield_addressof_replacements
3078 = gen_rtx_EXPR_LIST (VOIDmode, x,
3081 purge_bitfield_addressof_replacements));
3083 /* We replaced with a reg -- all done. */
3088 else if (validate_change (insn, loc, sub, 0))
3090 /* Remember the replacement so that the same one can be done
3091 on the REG_NOTES. */
3092 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3096 for (tem = purge_addressof_replacements;
3098 tem = XEXP (XEXP (tem, 1), 1))
3099 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3101 XEXP (XEXP (tem, 1), 0) = sub;
3104 purge_addressof_replacements
3105 = gen_rtx (EXPR_LIST, VOIDmode, XEXP (x, 0),
3106 gen_rtx_EXPR_LIST (VOIDmode, sub,
3107 purge_addressof_replacements));
3113 /* else give up and put it into the stack */
3116 else if (code == ADDRESSOF)
3118 put_addressof_into_stack (x, ht);
3121 else if (code == SET)
3123 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1, ht);
3124 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0, ht);
3128 /* Scan all subexpressions. */
3129 fmt = GET_RTX_FORMAT (code);
3130 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3133 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0, ht);
3134 else if (*fmt == 'E')
3135 for (j = 0; j < XVECLEN (x, i); j++)
3136 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0, ht);
3142 /* Return a new hash table entry in HT. */
3144 static struct hash_entry *
3145 insns_for_mem_newfunc (he, ht, k)
3146 struct hash_entry *he;
3147 struct hash_table *ht;
3148 hash_table_key k ATTRIBUTE_UNUSED;
3150 struct insns_for_mem_entry *ifmhe;
3154 ifmhe = ((struct insns_for_mem_entry *)
3155 hash_allocate (ht, sizeof (struct insns_for_mem_entry)));
3156 ifmhe->insns = NULL_RTX;
3161 /* Return a hash value for K, a REG. */
3163 static unsigned long
3164 insns_for_mem_hash (k)
3167 /* K is really a RTX. Just use the address as the hash value. */
3168 return (unsigned long) k;
3171 /* Return non-zero if K1 and K2 (two REGs) are the same. */
3174 insns_for_mem_comp (k1, k2)
3181 struct insns_for_mem_walk_info {
3182 /* The hash table that we are using to record which INSNs use which
3184 struct hash_table *ht;
3186 /* The INSN we are currently proessing. */
3189 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3190 to find the insns that use the REGs in the ADDRESSOFs. */
3194 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3195 that might be used in an ADDRESSOF expression, record this INSN in
3196 the hash table given by DATA (which is really a pointer to an
3197 insns_for_mem_walk_info structure). */
3200 insns_for_mem_walk (r, data)
3204 struct insns_for_mem_walk_info *ifmwi
3205 = (struct insns_for_mem_walk_info *) data;
3207 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3208 && GET_CODE (XEXP (*r, 0)) == REG)
3209 hash_lookup (ifmwi->ht, XEXP (*r, 0), /*create=*/1, /*copy=*/0);
3210 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3212 /* Lookup this MEM in the hashtable, creating it if necessary. */
3213 struct insns_for_mem_entry *ifme
3214 = (struct insns_for_mem_entry *) hash_lookup (ifmwi->ht,
3219 /* If we have not already recorded this INSN, do so now. Since
3220 we process the INSNs in order, we know that if we have
3221 recorded it it must be at the front of the list. */
3222 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3224 /* We do the allocation on the same obstack as is used for
3225 the hash table since this memory will not be used once
3226 the hash table is deallocated. */
3227 push_obstacks (&ifmwi->ht->memory, &ifmwi->ht->memory);
3228 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3237 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3238 which REGs in HT. */
3241 compute_insns_for_mem (insns, last_insn, ht)
3244 struct hash_table *ht;
3247 struct insns_for_mem_walk_info ifmwi;
3250 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3251 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3252 if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
3255 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3259 /* Helper function for purge_addressof called through for_each_rtx.
3260 Returns true iff the rtl is an ADDRESSOF. */
3262 is_addressof (rtl, data)
3264 void * data ATTRIBUTE_UNUSED;
3266 return GET_CODE (* rtl) == ADDRESSOF;
3269 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3270 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3274 purge_addressof (insns)
3278 struct hash_table ht;
3280 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3281 requires a fixup pass over the instruction stream to correct
3282 INSNs that depended on the REG being a REG, and not a MEM. But,
3283 these fixup passes are slow. Furthermore, most MEMs are not
3284 mentioned in very many instructions. So, we speed up the process
3285 by pre-calculating which REGs occur in which INSNs; that allows
3286 us to perform the fixup passes much more quickly. */
3287 hash_table_init (&ht,
3288 insns_for_mem_newfunc,
3290 insns_for_mem_comp);
3291 compute_insns_for_mem (insns, NULL_RTX, &ht);
3293 for (insn = insns; insn; insn = NEXT_INSN (insn))
3294 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3295 || GET_CODE (insn) == CALL_INSN)
3297 if (! purge_addressof_1 (&PATTERN (insn), insn,
3298 asm_noperands (PATTERN (insn)) > 0, 0, &ht))
3299 /* If we could not replace the ADDRESSOFs in the insn,
3300 something is wrong. */
3303 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, &ht))
3305 /* If we could not replace the ADDRESSOFs in the insn's notes,
3306 we can just remove the offending notes instead. */
3309 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3311 /* If we find a REG_RETVAL note then the insn is a libcall.
3312 Such insns must have REG_EQUAL notes as well, in order
3313 for later passes of the compiler to work. So it is not
3314 safe to delete the notes here, and instead we abort. */
3315 if (REG_NOTE_KIND (note) == REG_RETVAL)
3317 if (for_each_rtx (& note, is_addressof, NULL))
3318 remove_note (insn, note);
3324 hash_table_free (&ht);
3325 purge_bitfield_addressof_replacements = 0;
3326 purge_addressof_replacements = 0;
3328 /* REGs are shared. purge_addressof will destructively replace a REG
3329 with a MEM, which creates shared MEMs.
3331 Unfortunately, the children of put_reg_into_stack assume that MEMs
3332 referring to the same stack slot are shared (fixup_var_refs and
3333 the associated hash table code).
3335 So, we have to do another unsharing pass after we have flushed any
3336 REGs that had their address taken into the stack.
3338 It may be worth tracking whether or not we converted any REGs into
3339 MEMs to avoid this overhead when it is not needed. */
3340 unshare_all_rtl_again (get_insns ());
3343 /* Pass through the INSNS of function FNDECL and convert virtual register
3344 references to hard register references. */
3347 instantiate_virtual_regs (fndecl, insns)
3354 /* Compute the offsets to use for this function. */
3355 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3356 var_offset = STARTING_FRAME_OFFSET;
3357 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3358 out_arg_offset = STACK_POINTER_OFFSET;
3359 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl);
3361 /* Scan all variables and parameters of this function. For each that is
3362 in memory, instantiate all virtual registers if the result is a valid
3363 address. If not, we do it later. That will handle most uses of virtual
3364 regs on many machines. */
3365 instantiate_decls (fndecl, 1);
3367 /* Initialize recognition, indicating that volatile is OK. */
3370 /* Scan through all the insns, instantiating every virtual register still
3372 for (insn = insns; insn; insn = NEXT_INSN (insn))
3373 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3374 || GET_CODE (insn) == CALL_INSN)
3376 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3377 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3380 /* Instantiate the stack slots for the parm registers, for later use in
3381 addressof elimination. */
3382 for (i = 0; i < max_parm_reg; ++i)
3383 if (parm_reg_stack_loc[i])
3384 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3386 /* Now instantiate the remaining register equivalences for debugging info.
3387 These will not be valid addresses. */
3388 instantiate_decls (fndecl, 0);
3390 /* Indicate that, from now on, assign_stack_local should use
3391 frame_pointer_rtx. */
3392 virtuals_instantiated = 1;
3395 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3396 all virtual registers in their DECL_RTL's.
3398 If VALID_ONLY, do this only if the resulting address is still valid.
3399 Otherwise, always do it. */
3402 instantiate_decls (fndecl, valid_only)
3408 if (DECL_SAVED_INSNS (fndecl))
3409 /* When compiling an inline function, the obstack used for
3410 rtl allocation is the maybepermanent_obstack. Calling
3411 `resume_temporary_allocation' switches us back to that
3412 obstack while we process this function's parameters. */
3413 resume_temporary_allocation ();
3415 /* Process all parameters of the function. */
3416 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3418 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3420 instantiate_decl (DECL_RTL (decl), size, valid_only);
3422 /* If the parameter was promoted, then the incoming RTL mode may be
3423 larger than the declared type size. We must use the larger of
3425 size = MAX (GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl))), size);
3426 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3429 /* Now process all variables defined in the function or its subblocks. */
3430 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3432 if (DECL_INLINE (fndecl) || DECL_DEFER_OUTPUT (fndecl))
3434 /* Save all rtl allocated for this function by raising the
3435 high-water mark on the maybepermanent_obstack. */
3437 /* All further rtl allocation is now done in the current_obstack. */
3438 rtl_in_current_obstack ();
3442 /* Subroutine of instantiate_decls: Process all decls in the given
3443 BLOCK node and all its subblocks. */
3446 instantiate_decls_1 (let, valid_only)
3452 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3453 instantiate_decl (DECL_RTL (t), int_size_in_bytes (TREE_TYPE (t)),
3456 /* Process all subblocks. */
3457 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3458 instantiate_decls_1 (t, valid_only);
3461 /* Subroutine of the preceding procedures: Given RTL representing a
3462 decl and the size of the object, do any instantiation required.
3464 If VALID_ONLY is non-zero, it means that the RTL should only be
3465 changed if the new address is valid. */
3468 instantiate_decl (x, size, valid_only)
3473 enum machine_mode mode;
3476 /* If this is not a MEM, no need to do anything. Similarly if the
3477 address is a constant or a register that is not a virtual register. */
3479 if (x == 0 || GET_CODE (x) != MEM)
3483 if (CONSTANT_P (addr)
3484 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3485 || (GET_CODE (addr) == REG
3486 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3487 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3490 /* If we should only do this if the address is valid, copy the address.
3491 We need to do this so we can undo any changes that might make the
3492 address invalid. This copy is unfortunate, but probably can't be
3496 addr = copy_rtx (addr);
3498 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3500 if (valid_only && size >= 0)
3502 unsigned HOST_WIDE_INT decl_size = size;
3504 /* Now verify that the resulting address is valid for every integer or
3505 floating-point mode up to and including SIZE bytes long. We do this
3506 since the object might be accessed in any mode and frame addresses
3509 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3510 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3511 mode = GET_MODE_WIDER_MODE (mode))
3512 if (! memory_address_p (mode, addr))
3515 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3516 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3517 mode = GET_MODE_WIDER_MODE (mode))
3518 if (! memory_address_p (mode, addr))
3522 /* Put back the address now that we have updated it and we either know
3523 it is valid or we don't care whether it is valid. */
3528 /* Given a pointer to a piece of rtx and an optional pointer to the
3529 containing object, instantiate any virtual registers present in it.
3531 If EXTRA_INSNS, we always do the replacement and generate
3532 any extra insns before OBJECT. If it zero, we do nothing if replacement
3535 Return 1 if we either had nothing to do or if we were able to do the
3536 needed replacement. Return 0 otherwise; we only return zero if
3537 EXTRA_INSNS is zero.
3539 We first try some simple transformations to avoid the creation of extra
3543 instantiate_virtual_regs_1 (loc, object, extra_insns)
3551 HOST_WIDE_INT offset = 0;
3557 /* Re-start here to avoid recursion in common cases. */
3564 code = GET_CODE (x);
3566 /* Check for some special cases. */
3583 /* We are allowed to set the virtual registers. This means that
3584 the actual register should receive the source minus the
3585 appropriate offset. This is used, for example, in the handling
3586 of non-local gotos. */
3587 if (SET_DEST (x) == virtual_incoming_args_rtx)
3588 new = arg_pointer_rtx, offset = - in_arg_offset;
3589 else if (SET_DEST (x) == virtual_stack_vars_rtx)
3590 new = frame_pointer_rtx, offset = - var_offset;
3591 else if (SET_DEST (x) == virtual_stack_dynamic_rtx)
3592 new = stack_pointer_rtx, offset = - dynamic_offset;
3593 else if (SET_DEST (x) == virtual_outgoing_args_rtx)
3594 new = stack_pointer_rtx, offset = - out_arg_offset;
3595 else if (SET_DEST (x) == virtual_cfa_rtx)
3596 new = arg_pointer_rtx, offset = - cfa_offset;
3600 rtx src = SET_SRC (x);
3602 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3604 /* The only valid sources here are PLUS or REG. Just do
3605 the simplest possible thing to handle them. */
3606 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3610 if (GET_CODE (src) != REG)
3611 temp = force_operand (src, NULL_RTX);
3614 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3618 emit_insns_before (seq, object);
3621 if (! validate_change (object, &SET_SRC (x), temp, 0)
3628 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3633 /* Handle special case of virtual register plus constant. */
3634 if (CONSTANT_P (XEXP (x, 1)))
3636 rtx old, new_offset;
3638 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3639 if (GET_CODE (XEXP (x, 0)) == PLUS)
3641 rtx inner = XEXP (XEXP (x, 0), 0);
3643 if (inner == virtual_incoming_args_rtx)
3644 new = arg_pointer_rtx, offset = in_arg_offset;
3645 else if (inner == virtual_stack_vars_rtx)
3646 new = frame_pointer_rtx, offset = var_offset;
3647 else if (inner == virtual_stack_dynamic_rtx)
3648 new = stack_pointer_rtx, offset = dynamic_offset;
3649 else if (inner == virtual_outgoing_args_rtx)
3650 new = stack_pointer_rtx, offset = out_arg_offset;
3651 else if (inner == virtual_cfa_rtx)
3652 new = arg_pointer_rtx, offset = cfa_offset;
3659 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3661 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3664 else if (XEXP (x, 0) == virtual_incoming_args_rtx)
3665 new = arg_pointer_rtx, offset = in_arg_offset;
3666 else if (XEXP (x, 0) == virtual_stack_vars_rtx)
3667 new = frame_pointer_rtx, offset = var_offset;
3668 else if (XEXP (x, 0) == virtual_stack_dynamic_rtx)
3669 new = stack_pointer_rtx, offset = dynamic_offset;
3670 else if (XEXP (x, 0) == virtual_outgoing_args_rtx)
3671 new = stack_pointer_rtx, offset = out_arg_offset;
3672 else if (XEXP (x, 0) == virtual_cfa_rtx)
3673 new = arg_pointer_rtx, offset = cfa_offset;
3676 /* We know the second operand is a constant. Unless the
3677 first operand is a REG (which has been already checked),
3678 it needs to be checked. */
3679 if (GET_CODE (XEXP (x, 0)) != REG)
3687 new_offset = plus_constant (XEXP (x, 1), offset);
3689 /* If the new constant is zero, try to replace the sum with just
3691 if (new_offset == const0_rtx
3692 && validate_change (object, loc, new, 0))
3695 /* Next try to replace the register and new offset.
3696 There are two changes to validate here and we can't assume that
3697 in the case of old offset equals new just changing the register
3698 will yield a valid insn. In the interests of a little efficiency,
3699 however, we only call validate change once (we don't queue up the
3700 changes and then call apply_change_group). */
3704 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3705 : (XEXP (x, 0) = new,
3706 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3714 /* Otherwise copy the new constant into a register and replace
3715 constant with that register. */
3716 temp = gen_reg_rtx (Pmode);
3718 if (validate_change (object, &XEXP (x, 1), temp, 0))
3719 emit_insn_before (gen_move_insn (temp, new_offset), object);
3722 /* If that didn't work, replace this expression with a
3723 register containing the sum. */
3726 new = gen_rtx_PLUS (Pmode, new, new_offset);
3729 temp = force_operand (new, NULL_RTX);
3733 emit_insns_before (seq, object);
3734 if (! validate_change (object, loc, temp, 0)
3735 && ! validate_replace_rtx (x, temp, object))
3743 /* Fall through to generic two-operand expression case. */
3749 case DIV: case UDIV:
3750 case MOD: case UMOD:
3751 case AND: case IOR: case XOR:
3752 case ROTATERT: case ROTATE:
3753 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3755 case GE: case GT: case GEU: case GTU:
3756 case LE: case LT: case LEU: case LTU:
3757 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3758 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3763 /* Most cases of MEM that convert to valid addresses have already been
3764 handled by our scan of decls. The only special handling we
3765 need here is to make a copy of the rtx to ensure it isn't being
3766 shared if we have to change it to a pseudo.
3768 If the rtx is a simple reference to an address via a virtual register,
3769 it can potentially be shared. In such cases, first try to make it
3770 a valid address, which can also be shared. Otherwise, copy it and
3773 First check for common cases that need no processing. These are
3774 usually due to instantiation already being done on a previous instance
3778 if (CONSTANT_ADDRESS_P (temp)
3779 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3780 || temp == arg_pointer_rtx
3782 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3783 || temp == hard_frame_pointer_rtx
3785 || temp == frame_pointer_rtx)
3788 if (GET_CODE (temp) == PLUS
3789 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3790 && (XEXP (temp, 0) == frame_pointer_rtx
3791 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3792 || XEXP (temp, 0) == hard_frame_pointer_rtx
3794 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3795 || XEXP (temp, 0) == arg_pointer_rtx
3800 if (temp == virtual_stack_vars_rtx
3801 || temp == virtual_incoming_args_rtx
3802 || (GET_CODE (temp) == PLUS
3803 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3804 && (XEXP (temp, 0) == virtual_stack_vars_rtx
3805 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
3807 /* This MEM may be shared. If the substitution can be done without
3808 the need to generate new pseudos, we want to do it in place
3809 so all copies of the shared rtx benefit. The call below will
3810 only make substitutions if the resulting address is still
3813 Note that we cannot pass X as the object in the recursive call
3814 since the insn being processed may not allow all valid
3815 addresses. However, if we were not passed on object, we can
3816 only modify X without copying it if X will have a valid
3819 ??? Also note that this can still lose if OBJECT is an insn that
3820 has less restrictions on an address that some other insn.
3821 In that case, we will modify the shared address. This case
3822 doesn't seem very likely, though. One case where this could
3823 happen is in the case of a USE or CLOBBER reference, but we
3824 take care of that below. */
3826 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
3827 object ? object : x, 0))
3830 /* Otherwise make a copy and process that copy. We copy the entire
3831 RTL expression since it might be a PLUS which could also be
3833 *loc = x = copy_rtx (x);
3836 /* Fall through to generic unary operation case. */
3838 case STRICT_LOW_PART:
3840 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
3841 case SIGN_EXTEND: case ZERO_EXTEND:
3842 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
3843 case FLOAT: case FIX:
3844 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
3848 /* These case either have just one operand or we know that we need not
3849 check the rest of the operands. */
3855 /* If the operand is a MEM, see if the change is a valid MEM. If not,
3856 go ahead and make the invalid one, but do it to a copy. For a REG,
3857 just make the recursive call, since there's no chance of a problem. */
3859 if ((GET_CODE (XEXP (x, 0)) == MEM
3860 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
3862 || (GET_CODE (XEXP (x, 0)) == REG
3863 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
3866 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
3871 /* Try to replace with a PLUS. If that doesn't work, compute the sum
3872 in front of this insn and substitute the temporary. */
3873 if (x == virtual_incoming_args_rtx)
3874 new = arg_pointer_rtx, offset = in_arg_offset;
3875 else if (x == virtual_stack_vars_rtx)
3876 new = frame_pointer_rtx, offset = var_offset;
3877 else if (x == virtual_stack_dynamic_rtx)
3878 new = stack_pointer_rtx, offset = dynamic_offset;
3879 else if (x == virtual_outgoing_args_rtx)
3880 new = stack_pointer_rtx, offset = out_arg_offset;
3881 else if (x == virtual_cfa_rtx)
3882 new = arg_pointer_rtx, offset = cfa_offset;
3886 temp = plus_constant (new, offset);
3887 if (!validate_change (object, loc, temp, 0))
3893 temp = force_operand (temp, NULL_RTX);
3897 emit_insns_before (seq, object);
3898 if (! validate_change (object, loc, temp, 0)
3899 && ! validate_replace_rtx (x, temp, object))
3907 if (GET_CODE (XEXP (x, 0)) == REG)
3910 else if (GET_CODE (XEXP (x, 0)) == MEM)
3912 /* If we have a (addressof (mem ..)), do any instantiation inside
3913 since we know we'll be making the inside valid when we finally
3914 remove the ADDRESSOF. */
3915 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
3924 /* Scan all subexpressions. */
3925 fmt = GET_RTX_FORMAT (code);
3926 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3929 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
3932 else if (*fmt == 'E')
3933 for (j = 0; j < XVECLEN (x, i); j++)
3934 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
3941 /* Optimization: assuming this function does not receive nonlocal gotos,
3942 delete the handlers for such, as well as the insns to establish
3943 and disestablish them. */
3949 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3951 /* Delete the handler by turning off the flag that would
3952 prevent jump_optimize from deleting it.
3953 Also permit deletion of the nonlocal labels themselves
3954 if nothing local refers to them. */
3955 if (GET_CODE (insn) == CODE_LABEL)
3959 LABEL_PRESERVE_P (insn) = 0;
3961 /* Remove it from the nonlocal_label list, to avoid confusing
3963 for (t = nonlocal_labels, last_t = 0; t;
3964 last_t = t, t = TREE_CHAIN (t))
3965 if (DECL_RTL (TREE_VALUE (t)) == insn)
3970 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
3972 TREE_CHAIN (last_t) = TREE_CHAIN (t);
3975 if (GET_CODE (insn) == INSN)
3979 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
3980 if (reg_mentioned_p (t, PATTERN (insn)))
3986 || (nonlocal_goto_stack_level != 0
3987 && reg_mentioned_p (nonlocal_goto_stack_level,
3997 return max_parm_reg;
4000 /* Return the first insn following those generated by `assign_parms'. */
4003 get_first_nonparm_insn ()
4006 return NEXT_INSN (last_parm_insn);
4007 return get_insns ();
4010 /* Return the first NOTE_INSN_BLOCK_BEG note in the function.
4011 Crash if there is none. */
4014 get_first_block_beg ()
4016 register rtx searcher;
4017 register rtx insn = get_first_nonparm_insn ();
4019 for (searcher = insn; searcher; searcher = NEXT_INSN (searcher))
4020 if (GET_CODE (searcher) == NOTE
4021 && NOTE_LINE_NUMBER (searcher) == NOTE_INSN_BLOCK_BEG)
4024 abort (); /* Invalid call to this function. (See comments above.) */
4028 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4029 This means a type for which function calls must pass an address to the
4030 function or get an address back from the function.
4031 EXP may be a type node or an expression (whose type is tested). */
4034 aggregate_value_p (exp)
4037 int i, regno, nregs;
4040 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4042 if (TREE_CODE (type) == VOID_TYPE)
4044 if (RETURN_IN_MEMORY (type))
4046 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4047 and thus can't be returned in registers. */
4048 if (TREE_ADDRESSABLE (type))
4050 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4052 /* Make sure we have suitable call-clobbered regs to return
4053 the value in; if not, we must return it in memory. */
4054 reg = hard_function_value (type, 0, 0);
4056 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4058 if (GET_CODE (reg) != REG)
4061 regno = REGNO (reg);
4062 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
4063 for (i = 0; i < nregs; i++)
4064 if (! call_used_regs[regno + i])
4069 /* Assign RTL expressions to the function's parameters.
4070 This may involve copying them into registers and using
4071 those registers as the RTL for them. */
4074 assign_parms (fndecl)
4078 register rtx entry_parm = 0;
4079 register rtx stack_parm = 0;
4080 CUMULATIVE_ARGS args_so_far;
4081 enum machine_mode promoted_mode, passed_mode;
4082 enum machine_mode nominal_mode, promoted_nominal_mode;
4084 /* Total space needed so far for args on the stack,
4085 given as a constant and a tree-expression. */
4086 struct args_size stack_args_size;
4087 tree fntype = TREE_TYPE (fndecl);
4088 tree fnargs = DECL_ARGUMENTS (fndecl);
4089 /* This is used for the arg pointer when referring to stack args. */
4090 rtx internal_arg_pointer;
4091 /* This is a dummy PARM_DECL that we used for the function result if
4092 the function returns a structure. */
4093 tree function_result_decl = 0;
4094 #ifdef SETUP_INCOMING_VARARGS
4095 int varargs_setup = 0;
4097 rtx conversion_insns = 0;
4098 struct args_size alignment_pad;
4100 /* Nonzero if the last arg is named `__builtin_va_alist',
4101 which is used on some machines for old-fashioned non-ANSI varargs.h;
4102 this should be stuck onto the stack as if it had arrived there. */
4104 = (current_function_varargs
4106 && (parm = tree_last (fnargs)) != 0
4108 && (! strcmp (IDENTIFIER_POINTER (DECL_NAME (parm)),
4109 "__builtin_va_alist")));
4111 /* Nonzero if function takes extra anonymous args.
4112 This means the last named arg must be on the stack
4113 right before the anonymous ones. */
4115 = (TYPE_ARG_TYPES (fntype) != 0
4116 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4117 != void_type_node));
4119 current_function_stdarg = stdarg;
4121 /* If the reg that the virtual arg pointer will be translated into is
4122 not a fixed reg or is the stack pointer, make a copy of the virtual
4123 arg pointer, and address parms via the copy. The frame pointer is
4124 considered fixed even though it is not marked as such.
4126 The second time through, simply use ap to avoid generating rtx. */
4128 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4129 || ! (fixed_regs[ARG_POINTER_REGNUM]
4130 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4131 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4133 internal_arg_pointer = virtual_incoming_args_rtx;
4134 current_function_internal_arg_pointer = internal_arg_pointer;
4136 stack_args_size.constant = 0;
4137 stack_args_size.var = 0;
4139 /* If struct value address is treated as the first argument, make it so. */
4140 if (aggregate_value_p (DECL_RESULT (fndecl))
4141 && ! current_function_returns_pcc_struct
4142 && struct_value_incoming_rtx == 0)
4144 tree type = build_pointer_type (TREE_TYPE (fntype));
4146 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4148 DECL_ARG_TYPE (function_result_decl) = type;
4149 TREE_CHAIN (function_result_decl) = fnargs;
4150 fnargs = function_result_decl;
4153 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4154 parm_reg_stack_loc = (rtx *) xcalloc (max_parm_reg, sizeof (rtx));
4156 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4157 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4159 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, 0);
4162 /* We haven't yet found an argument that we must push and pretend the
4164 current_function_pretend_args_size = 0;
4166 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4168 struct args_size stack_offset;
4169 struct args_size arg_size;
4170 int passed_pointer = 0;
4171 int did_conversion = 0;
4172 tree passed_type = DECL_ARG_TYPE (parm);
4173 tree nominal_type = TREE_TYPE (parm);
4176 /* Set LAST_NAMED if this is last named arg before some
4178 int last_named = ((TREE_CHAIN (parm) == 0
4179 || DECL_NAME (TREE_CHAIN (parm)) == 0)
4180 && (stdarg || current_function_varargs));
4181 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4182 most machines, if this is a varargs/stdarg function, then we treat
4183 the last named arg as if it were anonymous too. */
4184 int named_arg = STRICT_ARGUMENT_NAMING ? 1 : ! last_named;
4186 if (TREE_TYPE (parm) == error_mark_node
4187 /* This can happen after weird syntax errors
4188 or if an enum type is defined among the parms. */
4189 || TREE_CODE (parm) != PARM_DECL
4190 || passed_type == NULL)
4192 DECL_INCOMING_RTL (parm) = DECL_RTL (parm)
4193 = gen_rtx_MEM (BLKmode, const0_rtx);
4194 TREE_USED (parm) = 1;
4198 /* For varargs.h function, save info about regs and stack space
4199 used by the individual args, not including the va_alist arg. */
4200 if (hide_last_arg && last_named)
4201 current_function_args_info = args_so_far;
4203 /* Find mode of arg as it is passed, and mode of arg
4204 as it should be during execution of this function. */
4205 passed_mode = TYPE_MODE (passed_type);
4206 nominal_mode = TYPE_MODE (nominal_type);
4208 /* If the parm's mode is VOID, its value doesn't matter,
4209 and avoid the usual things like emit_move_insn that could crash. */
4210 if (nominal_mode == VOIDmode)
4212 DECL_INCOMING_RTL (parm) = DECL_RTL (parm) = const0_rtx;
4216 /* If the parm is to be passed as a transparent union, use the
4217 type of the first field for the tests below. We have already
4218 verified that the modes are the same. */
4219 if (DECL_TRANSPARENT_UNION (parm)
4220 || (TREE_CODE (passed_type) == UNION_TYPE
4221 && TYPE_TRANSPARENT_UNION (passed_type)))
4222 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4224 /* See if this arg was passed by invisible reference. It is if
4225 it is an object whose size depends on the contents of the
4226 object itself or if the machine requires these objects be passed
4229 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
4230 && contains_placeholder_p (TYPE_SIZE (passed_type)))
4231 || TREE_ADDRESSABLE (passed_type)
4232 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4233 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4234 passed_type, named_arg)
4238 passed_type = nominal_type = build_pointer_type (passed_type);
4240 passed_mode = nominal_mode = Pmode;
4243 promoted_mode = passed_mode;
4245 #ifdef PROMOTE_FUNCTION_ARGS
4246 /* Compute the mode in which the arg is actually extended to. */
4247 unsignedp = TREE_UNSIGNED (passed_type);
4248 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4251 /* Let machine desc say which reg (if any) the parm arrives in.
4252 0 means it arrives on the stack. */
4253 #ifdef FUNCTION_INCOMING_ARG
4254 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4255 passed_type, named_arg);
4257 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4258 passed_type, named_arg);
4261 if (entry_parm == 0)
4262 promoted_mode = passed_mode;
4264 #ifdef SETUP_INCOMING_VARARGS
4265 /* If this is the last named parameter, do any required setup for
4266 varargs or stdargs. We need to know about the case of this being an
4267 addressable type, in which case we skip the registers it
4268 would have arrived in.
4270 For stdargs, LAST_NAMED will be set for two parameters, the one that
4271 is actually the last named, and the dummy parameter. We only
4272 want to do this action once.
4274 Also, indicate when RTL generation is to be suppressed. */
4275 if (last_named && !varargs_setup)
4277 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
4278 current_function_pretend_args_size, 0);
4283 /* Determine parm's home in the stack,
4284 in case it arrives in the stack or we should pretend it did.
4286 Compute the stack position and rtx where the argument arrives
4289 There is one complexity here: If this was a parameter that would
4290 have been passed in registers, but wasn't only because it is
4291 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4292 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4293 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4294 0 as it was the previous time. */
4296 pretend_named = named_arg || PRETEND_OUTGOING_VARARGS_NAMED;
4297 locate_and_pad_parm (promoted_mode, passed_type,
4298 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4301 #ifdef FUNCTION_INCOMING_ARG
4302 FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4304 pretend_named) != 0,
4306 FUNCTION_ARG (args_so_far, promoted_mode,
4308 pretend_named) != 0,
4311 fndecl, &stack_args_size, &stack_offset, &arg_size,
4315 rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
4317 if (offset_rtx == const0_rtx)
4318 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4320 stack_parm = gen_rtx_MEM (promoted_mode,
4321 gen_rtx_PLUS (Pmode,
4322 internal_arg_pointer,
4325 set_mem_attributes (stack_parm, parm, 1);
4328 /* If this parameter was passed both in registers and in the stack,
4329 use the copy on the stack. */
4330 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4333 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4334 /* If this parm was passed part in regs and part in memory,
4335 pretend it arrived entirely in memory
4336 by pushing the register-part onto the stack.
4338 In the special case of a DImode or DFmode that is split,
4339 we could put it together in a pseudoreg directly,
4340 but for now that's not worth bothering with. */
4344 int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4345 passed_type, named_arg);
4349 current_function_pretend_args_size
4350 = (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
4351 / (PARM_BOUNDARY / BITS_PER_UNIT)
4352 * (PARM_BOUNDARY / BITS_PER_UNIT));
4354 /* Handle calls that pass values in multiple non-contiguous
4355 locations. The Irix 6 ABI has examples of this. */
4356 if (GET_CODE (entry_parm) == PARALLEL)
4357 emit_group_store (validize_mem (stack_parm), entry_parm,
4358 int_size_in_bytes (TREE_TYPE (parm)),
4359 TYPE_ALIGN (TREE_TYPE (parm)));
4362 move_block_from_reg (REGNO (entry_parm),
4363 validize_mem (stack_parm), nregs,
4364 int_size_in_bytes (TREE_TYPE (parm)));
4366 entry_parm = stack_parm;
4371 /* If we didn't decide this parm came in a register,
4372 by default it came on the stack. */
4373 if (entry_parm == 0)
4374 entry_parm = stack_parm;
4376 /* Record permanently how this parm was passed. */
4377 DECL_INCOMING_RTL (parm) = entry_parm;
4379 /* If there is actually space on the stack for this parm,
4380 count it in stack_args_size; otherwise set stack_parm to 0
4381 to indicate there is no preallocated stack slot for the parm. */
4383 if (entry_parm == stack_parm
4384 || (GET_CODE (entry_parm) == PARALLEL
4385 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4386 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4387 /* On some machines, even if a parm value arrives in a register
4388 there is still an (uninitialized) stack slot allocated for it.
4390 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4391 whether this parameter already has a stack slot allocated,
4392 because an arg block exists only if current_function_args_size
4393 is larger than some threshold, and we haven't calculated that
4394 yet. So, for now, we just assume that stack slots never exist
4396 || REG_PARM_STACK_SPACE (fndecl) > 0
4400 stack_args_size.constant += arg_size.constant;
4402 ADD_PARM_SIZE (stack_args_size, arg_size.var);
4405 /* No stack slot was pushed for this parm. */
4408 /* Update info on where next arg arrives in registers. */
4410 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4411 passed_type, named_arg);
4413 /* If we can't trust the parm stack slot to be aligned enough
4414 for its ultimate type, don't use that slot after entry.
4415 We'll make another stack slot, if we need one. */
4417 unsigned int thisparm_boundary
4418 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4420 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4424 /* If parm was passed in memory, and we need to convert it on entry,
4425 don't store it back in that same slot. */
4427 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4430 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4431 in the mode in which it arrives.
4432 STACK_PARM is an RTX for a stack slot where the parameter can live
4433 during the function (in case we want to put it there).
4434 STACK_PARM is 0 if no stack slot was pushed for it.
4436 Now output code if necessary to convert ENTRY_PARM to
4437 the type in which this function declares it,
4438 and store that result in an appropriate place,
4439 which may be a pseudo reg, may be STACK_PARM,
4440 or may be a local stack slot if STACK_PARM is 0.
4442 Set DECL_RTL to that place. */
4444 if (nominal_mode == BLKmode || GET_CODE (entry_parm) == PARALLEL)
4446 /* If a BLKmode arrives in registers, copy it to a stack slot.
4447 Handle calls that pass values in multiple non-contiguous
4448 locations. The Irix 6 ABI has examples of this. */
4449 if (GET_CODE (entry_parm) == REG
4450 || GET_CODE (entry_parm) == PARALLEL)
4453 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
4456 /* Note that we will be storing an integral number of words.
4457 So we have to be careful to ensure that we allocate an
4458 integral number of words. We do this below in the
4459 assign_stack_local if space was not allocated in the argument
4460 list. If it was, this will not work if PARM_BOUNDARY is not
4461 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4462 if it becomes a problem. */
4464 if (stack_parm == 0)
4467 = assign_stack_local (GET_MODE (entry_parm),
4469 set_mem_attributes (stack_parm, parm, 1);
4472 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4475 /* Handle calls that pass values in multiple non-contiguous
4476 locations. The Irix 6 ABI has examples of this. */
4477 if (GET_CODE (entry_parm) == PARALLEL)
4478 emit_group_store (validize_mem (stack_parm), entry_parm,
4479 int_size_in_bytes (TREE_TYPE (parm)),
4480 TYPE_ALIGN (TREE_TYPE (parm)));
4482 move_block_from_reg (REGNO (entry_parm),
4483 validize_mem (stack_parm),
4484 size_stored / UNITS_PER_WORD,
4485 int_size_in_bytes (TREE_TYPE (parm)));
4487 DECL_RTL (parm) = stack_parm;
4489 else if (! ((! optimize
4490 && ! DECL_REGISTER (parm)
4491 && ! DECL_INLINE (fndecl))
4492 /* layout_decl may set this. */
4493 || TREE_ADDRESSABLE (parm)
4494 || TREE_SIDE_EFFECTS (parm)
4495 /* If -ffloat-store specified, don't put explicit
4496 float variables into registers. */
4497 || (flag_float_store
4498 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4499 /* Always assign pseudo to structure return or item passed
4500 by invisible reference. */
4501 || passed_pointer || parm == function_result_decl)
4503 /* Store the parm in a pseudoregister during the function, but we
4504 may need to do it in a wider mode. */
4506 register rtx parmreg;
4507 unsigned int regno, regnoi = 0, regnor = 0;
4509 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4511 promoted_nominal_mode
4512 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4514 parmreg = gen_reg_rtx (promoted_nominal_mode);
4515 mark_user_reg (parmreg);
4517 /* If this was an item that we received a pointer to, set DECL_RTL
4522 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)), parmreg);
4523 set_mem_attributes (DECL_RTL (parm), parm, 1);
4526 DECL_RTL (parm) = parmreg;
4528 /* Copy the value into the register. */
4529 if (nominal_mode != passed_mode
4530 || promoted_nominal_mode != promoted_mode)
4533 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4534 mode, by the caller. We now have to convert it to
4535 NOMINAL_MODE, if different. However, PARMREG may be in
4536 a different mode than NOMINAL_MODE if it is being stored
4539 If ENTRY_PARM is a hard register, it might be in a register
4540 not valid for operating in its mode (e.g., an odd-numbered
4541 register for a DFmode). In that case, moves are the only
4542 thing valid, so we can't do a convert from there. This
4543 occurs when the calling sequence allow such misaligned
4546 In addition, the conversion may involve a call, which could
4547 clobber parameters which haven't been copied to pseudo
4548 registers yet. Therefore, we must first copy the parm to
4549 a pseudo reg here, and save the conversion until after all
4550 parameters have been moved. */
4552 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4554 emit_move_insn (tempreg, validize_mem (entry_parm));
4556 push_to_sequence (conversion_insns);
4557 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4559 /* TREE_USED gets set erroneously during expand_assignment. */
4560 save_tree_used = TREE_USED (parm);
4561 expand_assignment (parm,
4562 make_tree (nominal_type, tempreg), 0, 0);
4563 TREE_USED (parm) = save_tree_used;
4564 conversion_insns = get_insns ();
4569 emit_move_insn (parmreg, validize_mem (entry_parm));
4571 /* If we were passed a pointer but the actual value
4572 can safely live in a register, put it in one. */
4573 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4575 && ! DECL_REGISTER (parm)
4576 && ! DECL_INLINE (fndecl))
4577 /* layout_decl may set this. */
4578 || TREE_ADDRESSABLE (parm)
4579 || TREE_SIDE_EFFECTS (parm)
4580 /* If -ffloat-store specified, don't put explicit
4581 float variables into registers. */
4582 || (flag_float_store
4583 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE)))
4585 /* We can't use nominal_mode, because it will have been set to
4586 Pmode above. We must use the actual mode of the parm. */
4587 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4588 mark_user_reg (parmreg);
4589 emit_move_insn (parmreg, DECL_RTL (parm));
4590 DECL_RTL (parm) = parmreg;
4591 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4595 #ifdef FUNCTION_ARG_CALLEE_COPIES
4596 /* If we are passed an arg by reference and it is our responsibility
4597 to make a copy, do it now.
4598 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4599 original argument, so we must recreate them in the call to
4600 FUNCTION_ARG_CALLEE_COPIES. */
4601 /* ??? Later add code to handle the case that if the argument isn't
4602 modified, don't do the copy. */
4604 else if (passed_pointer
4605 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4606 TYPE_MODE (DECL_ARG_TYPE (parm)),
4607 DECL_ARG_TYPE (parm),
4609 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4612 tree type = DECL_ARG_TYPE (parm);
4614 /* This sequence may involve a library call perhaps clobbering
4615 registers that haven't been copied to pseudos yet. */
4617 push_to_sequence (conversion_insns);
4619 if (!COMPLETE_TYPE_P (type)
4620 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4621 /* This is a variable sized object. */
4622 copy = gen_rtx_MEM (BLKmode,
4623 allocate_dynamic_stack_space
4624 (expr_size (parm), NULL_RTX,
4625 TYPE_ALIGN (type)));
4627 copy = assign_stack_temp (TYPE_MODE (type),
4628 int_size_in_bytes (type), 1);
4629 set_mem_attributes (copy, parm, 1);
4631 store_expr (parm, copy, 0);
4632 emit_move_insn (parmreg, XEXP (copy, 0));
4633 if (current_function_check_memory_usage)
4634 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
4635 XEXP (copy, 0), Pmode,
4636 GEN_INT (int_size_in_bytes (type)),
4637 TYPE_MODE (sizetype),
4638 GEN_INT (MEMORY_USE_RW),
4639 TYPE_MODE (integer_type_node));
4640 conversion_insns = get_insns ();
4644 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4646 /* In any case, record the parm's desired stack location
4647 in case we later discover it must live in the stack.
4649 If it is a COMPLEX value, store the stack location for both
4652 if (GET_CODE (parmreg) == CONCAT)
4653 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4655 regno = REGNO (parmreg);
4657 if (regno >= max_parm_reg)
4660 int old_max_parm_reg = max_parm_reg;
4662 /* It's slow to expand this one register at a time,
4663 but it's also rare and we need max_parm_reg to be
4664 precisely correct. */
4665 max_parm_reg = regno + 1;
4666 new = (rtx *) xrealloc (parm_reg_stack_loc,
4667 max_parm_reg * sizeof (rtx));
4668 bzero ((char *) (new + old_max_parm_reg),
4669 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4670 parm_reg_stack_loc = new;
4673 if (GET_CODE (parmreg) == CONCAT)
4675 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
4677 regnor = REGNO (gen_realpart (submode, parmreg));
4678 regnoi = REGNO (gen_imagpart (submode, parmreg));
4680 if (stack_parm != 0)
4682 parm_reg_stack_loc[regnor]
4683 = gen_realpart (submode, stack_parm);
4684 parm_reg_stack_loc[regnoi]
4685 = gen_imagpart (submode, stack_parm);
4689 parm_reg_stack_loc[regnor] = 0;
4690 parm_reg_stack_loc[regnoi] = 0;
4694 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
4696 /* Mark the register as eliminable if we did no conversion
4697 and it was copied from memory at a fixed offset,
4698 and the arg pointer was not copied to a pseudo-reg.
4699 If the arg pointer is a pseudo reg or the offset formed
4700 an invalid address, such memory-equivalences
4701 as we make here would screw up life analysis for it. */
4702 if (nominal_mode == passed_mode
4705 && GET_CODE (stack_parm) == MEM
4706 && stack_offset.var == 0
4707 && reg_mentioned_p (virtual_incoming_args_rtx,
4708 XEXP (stack_parm, 0)))
4710 rtx linsn = get_last_insn ();
4713 /* Mark complex types separately. */
4714 if (GET_CODE (parmreg) == CONCAT)
4715 /* Scan backwards for the set of the real and
4717 for (sinsn = linsn; sinsn != 0;
4718 sinsn = prev_nonnote_insn (sinsn))
4720 set = single_set (sinsn);
4722 && SET_DEST (set) == regno_reg_rtx [regnoi])
4724 = gen_rtx_EXPR_LIST (REG_EQUIV,
4725 parm_reg_stack_loc[regnoi],
4728 && SET_DEST (set) == regno_reg_rtx [regnor])
4730 = gen_rtx_EXPR_LIST (REG_EQUIV,
4731 parm_reg_stack_loc[regnor],
4734 else if ((set = single_set (linsn)) != 0
4735 && SET_DEST (set) == parmreg)
4737 = gen_rtx_EXPR_LIST (REG_EQUIV,
4738 stack_parm, REG_NOTES (linsn));
4741 /* For pointer data type, suggest pointer register. */
4742 if (POINTER_TYPE_P (TREE_TYPE (parm)))
4743 mark_reg_pointer (parmreg,
4744 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
4749 /* Value must be stored in the stack slot STACK_PARM
4750 during function execution. */
4752 if (promoted_mode != nominal_mode)
4754 /* Conversion is required. */
4755 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4757 emit_move_insn (tempreg, validize_mem (entry_parm));
4759 push_to_sequence (conversion_insns);
4760 entry_parm = convert_to_mode (nominal_mode, tempreg,
4761 TREE_UNSIGNED (TREE_TYPE (parm)));
4764 /* ??? This may need a big-endian conversion on sparc64. */
4765 stack_parm = change_address (stack_parm, nominal_mode,
4768 conversion_insns = get_insns ();
4773 if (entry_parm != stack_parm)
4775 if (stack_parm == 0)
4778 = assign_stack_local (GET_MODE (entry_parm),
4779 GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
4780 set_mem_attributes (stack_parm, parm, 1);
4783 if (promoted_mode != nominal_mode)
4785 push_to_sequence (conversion_insns);
4786 emit_move_insn (validize_mem (stack_parm),
4787 validize_mem (entry_parm));
4788 conversion_insns = get_insns ();
4792 emit_move_insn (validize_mem (stack_parm),
4793 validize_mem (entry_parm));
4795 if (current_function_check_memory_usage)
4797 push_to_sequence (conversion_insns);
4798 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
4799 XEXP (stack_parm, 0), Pmode,
4800 GEN_INT (GET_MODE_SIZE (GET_MODE
4802 TYPE_MODE (sizetype),
4803 GEN_INT (MEMORY_USE_RW),
4804 TYPE_MODE (integer_type_node));
4806 conversion_insns = get_insns ();
4809 DECL_RTL (parm) = stack_parm;
4812 /* If this "parameter" was the place where we are receiving the
4813 function's incoming structure pointer, set up the result. */
4814 if (parm == function_result_decl)
4816 tree result = DECL_RESULT (fndecl);
4819 = gen_rtx_MEM (DECL_MODE (result), DECL_RTL (parm));
4821 set_mem_attributes (DECL_RTL (result), result, 1);
4825 /* Output all parameter conversion instructions (possibly including calls)
4826 now that all parameters have been copied out of hard registers. */
4827 emit_insns (conversion_insns);
4829 last_parm_insn = get_last_insn ();
4831 current_function_args_size = stack_args_size.constant;
4833 /* Adjust function incoming argument size for alignment and
4836 #ifdef REG_PARM_STACK_SPACE
4837 #ifndef MAYBE_REG_PARM_STACK_SPACE
4838 current_function_args_size = MAX (current_function_args_size,
4839 REG_PARM_STACK_SPACE (fndecl));
4843 #ifdef STACK_BOUNDARY
4844 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
4846 current_function_args_size
4847 = ((current_function_args_size + STACK_BYTES - 1)
4848 / STACK_BYTES) * STACK_BYTES;
4851 #ifdef ARGS_GROW_DOWNWARD
4852 current_function_arg_offset_rtx
4853 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
4854 : expand_expr (size_diffop (stack_args_size.var,
4855 size_int (-stack_args_size.constant)),
4856 NULL_RTX, VOIDmode, EXPAND_MEMORY_USE_BAD));
4858 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
4861 /* See how many bytes, if any, of its args a function should try to pop
4864 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
4865 current_function_args_size);
4867 /* For stdarg.h function, save info about
4868 regs and stack space used by the named args. */
4871 current_function_args_info = args_so_far;
4873 /* Set the rtx used for the function return value. Put this in its
4874 own variable so any optimizers that need this information don't have
4875 to include tree.h. Do this here so it gets done when an inlined
4876 function gets output. */
4878 current_function_return_rtx = DECL_RTL (DECL_RESULT (fndecl));
4881 /* Indicate whether REGNO is an incoming argument to the current function
4882 that was promoted to a wider mode. If so, return the RTX for the
4883 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
4884 that REGNO is promoted from and whether the promotion was signed or
4887 #ifdef PROMOTE_FUNCTION_ARGS
4890 promoted_input_arg (regno, pmode, punsignedp)
4892 enum machine_mode *pmode;
4897 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
4898 arg = TREE_CHAIN (arg))
4899 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
4900 && REGNO (DECL_INCOMING_RTL (arg)) == regno
4901 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
4903 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
4904 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
4906 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
4907 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
4908 && mode != DECL_MODE (arg))
4910 *pmode = DECL_MODE (arg);
4911 *punsignedp = unsignedp;
4912 return DECL_INCOMING_RTL (arg);
4921 /* Compute the size and offset from the start of the stacked arguments for a
4922 parm passed in mode PASSED_MODE and with type TYPE.
4924 INITIAL_OFFSET_PTR points to the current offset into the stacked
4927 The starting offset and size for this parm are returned in *OFFSET_PTR
4928 and *ARG_SIZE_PTR, respectively.
4930 IN_REGS is non-zero if the argument will be passed in registers. It will
4931 never be set if REG_PARM_STACK_SPACE is not defined.
4933 FNDECL is the function in which the argument was defined.
4935 There are two types of rounding that are done. The first, controlled by
4936 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
4937 list to be aligned to the specific boundary (in bits). This rounding
4938 affects the initial and starting offsets, but not the argument size.
4940 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
4941 optionally rounds the size of the parm to PARM_BOUNDARY. The
4942 initial offset is not affected by this rounding, while the size always
4943 is and the starting offset may be. */
4945 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
4946 initial_offset_ptr is positive because locate_and_pad_parm's
4947 callers pass in the total size of args so far as
4948 initial_offset_ptr. arg_size_ptr is always positive.*/
4951 locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
4952 initial_offset_ptr, offset_ptr, arg_size_ptr,
4954 enum machine_mode passed_mode;
4956 int in_regs ATTRIBUTE_UNUSED;
4957 tree fndecl ATTRIBUTE_UNUSED;
4958 struct args_size *initial_offset_ptr;
4959 struct args_size *offset_ptr;
4960 struct args_size *arg_size_ptr;
4961 struct args_size *alignment_pad;
4965 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
4966 enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
4967 int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
4969 #ifdef REG_PARM_STACK_SPACE
4970 /* If we have found a stack parm before we reach the end of the
4971 area reserved for registers, skip that area. */
4974 int reg_parm_stack_space = 0;
4976 #ifdef MAYBE_REG_PARM_STACK_SPACE
4977 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
4979 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
4981 if (reg_parm_stack_space > 0)
4983 if (initial_offset_ptr->var)
4985 initial_offset_ptr->var
4986 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
4987 ssize_int (reg_parm_stack_space));
4988 initial_offset_ptr->constant = 0;
4990 else if (initial_offset_ptr->constant < reg_parm_stack_space)
4991 initial_offset_ptr->constant = reg_parm_stack_space;
4994 #endif /* REG_PARM_STACK_SPACE */
4996 arg_size_ptr->var = 0;
4997 arg_size_ptr->constant = 0;
4999 #ifdef ARGS_GROW_DOWNWARD
5000 if (initial_offset_ptr->var)
5002 offset_ptr->constant = 0;
5003 offset_ptr->var = size_binop (MINUS_EXPR, ssize_int (0),
5004 initial_offset_ptr->var);
5008 offset_ptr->constant = - initial_offset_ptr->constant;
5009 offset_ptr->var = 0;
5011 if (where_pad != none
5012 && (TREE_CODE (sizetree) != INTEGER_CST
5013 || ((TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)))
5014 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5015 SUB_PARM_SIZE (*offset_ptr, sizetree);
5016 if (where_pad != downward)
5017 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad);
5018 if (initial_offset_ptr->var)
5019 arg_size_ptr->var = size_binop (MINUS_EXPR,
5020 size_binop (MINUS_EXPR,
5022 initial_offset_ptr->var),
5026 arg_size_ptr->constant = (- initial_offset_ptr->constant
5027 - offset_ptr->constant);
5029 #else /* !ARGS_GROW_DOWNWARD */
5030 pad_to_arg_alignment (initial_offset_ptr, boundary, alignment_pad);
5031 *offset_ptr = *initial_offset_ptr;
5033 #ifdef PUSH_ROUNDING
5034 if (passed_mode != BLKmode)
5035 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5038 /* Pad_below needs the pre-rounded size to know how much to pad below
5039 so this must be done before rounding up. */
5040 if (where_pad == downward
5041 /* However, BLKmode args passed in regs have their padding done elsewhere.
5042 The stack slot must be able to hold the entire register. */
5043 && !(in_regs && passed_mode == BLKmode))
5044 pad_below (offset_ptr, passed_mode, sizetree);
5046 if (where_pad != none
5047 && (TREE_CODE (sizetree) != INTEGER_CST
5048 || ((TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)))
5049 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5051 ADD_PARM_SIZE (*arg_size_ptr, sizetree);
5052 #endif /* ARGS_GROW_DOWNWARD */
5055 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5056 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5059 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad)
5060 struct args_size *offset_ptr;
5062 struct args_size *alignment_pad;
5064 tree save_var = NULL_TREE;
5065 HOST_WIDE_INT save_constant = 0;
5067 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5069 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5071 save_var = offset_ptr->var;
5072 save_constant = offset_ptr->constant;
5075 alignment_pad->var = NULL_TREE;
5076 alignment_pad->constant = 0;
5078 if (boundary > BITS_PER_UNIT)
5080 if (offset_ptr->var)
5083 #ifdef ARGS_GROW_DOWNWARD
5088 (ARGS_SIZE_TREE (*offset_ptr),
5089 boundary / BITS_PER_UNIT);
5090 offset_ptr->constant = 0; /*?*/
5091 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5092 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5097 offset_ptr->constant =
5098 #ifdef ARGS_GROW_DOWNWARD
5099 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
5101 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
5103 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5104 alignment_pad->constant = offset_ptr->constant - save_constant;
5109 #ifndef ARGS_GROW_DOWNWARD
5111 pad_below (offset_ptr, passed_mode, sizetree)
5112 struct args_size *offset_ptr;
5113 enum machine_mode passed_mode;
5116 if (passed_mode != BLKmode)
5118 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5119 offset_ptr->constant
5120 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5121 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5122 - GET_MODE_SIZE (passed_mode));
5126 if (TREE_CODE (sizetree) != INTEGER_CST
5127 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5129 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5130 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5132 ADD_PARM_SIZE (*offset_ptr, s2);
5133 SUB_PARM_SIZE (*offset_ptr, sizetree);
5139 /* Walk the tree of blocks describing the binding levels within a function
5140 and warn about uninitialized variables.
5141 This is done after calling flow_analysis and before global_alloc
5142 clobbers the pseudo-regs to hard regs. */
5145 uninitialized_vars_warning (block)
5148 register tree decl, sub;
5149 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5151 if (warn_uninitialized
5152 && TREE_CODE (decl) == VAR_DECL
5153 /* These warnings are unreliable for and aggregates
5154 because assigning the fields one by one can fail to convince
5155 flow.c that the entire aggregate was initialized.
5156 Unions are troublesome because members may be shorter. */
5157 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5158 && DECL_RTL (decl) != 0
5159 && GET_CODE (DECL_RTL (decl)) == REG
5160 /* Global optimizations can make it difficult to determine if a
5161 particular variable has been initialized. However, a VAR_DECL
5162 with a nonzero DECL_INITIAL had an initializer, so do not
5163 claim it is potentially uninitialized.
5165 We do not care about the actual value in DECL_INITIAL, so we do
5166 not worry that it may be a dangling pointer. */
5167 && DECL_INITIAL (decl) == NULL_TREE
5168 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5169 warning_with_decl (decl,
5170 "`%s' might be used uninitialized in this function");
5172 && TREE_CODE (decl) == VAR_DECL
5173 && DECL_RTL (decl) != 0
5174 && GET_CODE (DECL_RTL (decl)) == REG
5175 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5176 warning_with_decl (decl,
5177 "variable `%s' might be clobbered by `longjmp' or `vfork'");
5179 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5180 uninitialized_vars_warning (sub);
5183 /* Do the appropriate part of uninitialized_vars_warning
5184 but for arguments instead of local variables. */
5187 setjmp_args_warning ()
5190 for (decl = DECL_ARGUMENTS (current_function_decl);
5191 decl; decl = TREE_CHAIN (decl))
5192 if (DECL_RTL (decl) != 0
5193 && GET_CODE (DECL_RTL (decl)) == REG
5194 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5195 warning_with_decl (decl, "argument `%s' might be clobbered by `longjmp' or `vfork'");
5198 /* If this function call setjmp, put all vars into the stack
5199 unless they were declared `register'. */
5202 setjmp_protect (block)
5205 register tree decl, sub;
5206 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5207 if ((TREE_CODE (decl) == VAR_DECL
5208 || TREE_CODE (decl) == PARM_DECL)
5209 && DECL_RTL (decl) != 0
5210 && (GET_CODE (DECL_RTL (decl)) == REG
5211 || (GET_CODE (DECL_RTL (decl)) == MEM
5212 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5213 /* If this variable came from an inline function, it must be
5214 that its life doesn't overlap the setjmp. If there was a
5215 setjmp in the function, it would already be in memory. We
5216 must exclude such variable because their DECL_RTL might be
5217 set to strange things such as virtual_stack_vars_rtx. */
5218 && ! DECL_FROM_INLINE (decl)
5220 #ifdef NON_SAVING_SETJMP
5221 /* If longjmp doesn't restore the registers,
5222 don't put anything in them. */
5226 ! DECL_REGISTER (decl)))
5227 put_var_into_stack (decl);
5228 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5229 setjmp_protect (sub);
5232 /* Like the previous function, but for args instead of local variables. */
5235 setjmp_protect_args ()
5238 for (decl = DECL_ARGUMENTS (current_function_decl);
5239 decl; decl = TREE_CHAIN (decl))
5240 if ((TREE_CODE (decl) == VAR_DECL
5241 || TREE_CODE (decl) == PARM_DECL)
5242 && DECL_RTL (decl) != 0
5243 && (GET_CODE (DECL_RTL (decl)) == REG
5244 || (GET_CODE (DECL_RTL (decl)) == MEM
5245 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5247 /* If longjmp doesn't restore the registers,
5248 don't put anything in them. */
5249 #ifdef NON_SAVING_SETJMP
5253 ! DECL_REGISTER (decl)))
5254 put_var_into_stack (decl);
5257 /* Return the context-pointer register corresponding to DECL,
5258 or 0 if it does not need one. */
5261 lookup_static_chain (decl)
5264 tree context = decl_function_context (decl);
5268 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5271 /* We treat inline_function_decl as an alias for the current function
5272 because that is the inline function whose vars, types, etc.
5273 are being merged into the current function.
5274 See expand_inline_function. */
5275 if (context == current_function_decl || context == inline_function_decl)
5276 return virtual_stack_vars_rtx;
5278 for (link = context_display; link; link = TREE_CHAIN (link))
5279 if (TREE_PURPOSE (link) == context)
5280 return RTL_EXPR_RTL (TREE_VALUE (link));
5285 /* Convert a stack slot address ADDR for variable VAR
5286 (from a containing function)
5287 into an address valid in this function (using a static chain). */
5290 fix_lexical_addr (addr, var)
5295 HOST_WIDE_INT displacement;
5296 tree context = decl_function_context (var);
5297 struct function *fp;
5300 /* If this is the present function, we need not do anything. */
5301 if (context == current_function_decl || context == inline_function_decl)
5304 for (fp = outer_function_chain; fp; fp = fp->next)
5305 if (fp->decl == context)
5311 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5312 addr = XEXP (XEXP (addr, 0), 0);
5314 /* Decode given address as base reg plus displacement. */
5315 if (GET_CODE (addr) == REG)
5316 basereg = addr, displacement = 0;
5317 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5318 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5322 /* We accept vars reached via the containing function's
5323 incoming arg pointer and via its stack variables pointer. */
5324 if (basereg == fp->internal_arg_pointer)
5326 /* If reached via arg pointer, get the arg pointer value
5327 out of that function's stack frame.
5329 There are two cases: If a separate ap is needed, allocate a
5330 slot in the outer function for it and dereference it that way.
5331 This is correct even if the real ap is actually a pseudo.
5332 Otherwise, just adjust the offset from the frame pointer to
5335 #ifdef NEED_SEPARATE_AP
5338 if (fp->x_arg_pointer_save_area == 0)
5339 fp->x_arg_pointer_save_area
5340 = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, fp);
5342 addr = fix_lexical_addr (XEXP (fp->x_arg_pointer_save_area, 0), var);
5343 addr = memory_address (Pmode, addr);
5345 base = gen_rtx_MEM (Pmode, addr);
5346 MEM_ALIAS_SET (base) = get_frame_alias_set ();
5347 base = copy_to_reg (base);
5349 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5350 base = lookup_static_chain (var);
5354 else if (basereg == virtual_stack_vars_rtx)
5356 /* This is the same code as lookup_static_chain, duplicated here to
5357 avoid an extra call to decl_function_context. */
5360 for (link = context_display; link; link = TREE_CHAIN (link))
5361 if (TREE_PURPOSE (link) == context)
5363 base = RTL_EXPR_RTL (TREE_VALUE (link));
5371 /* Use same offset, relative to appropriate static chain or argument
5373 return plus_constant (base, displacement);
5376 /* Return the address of the trampoline for entering nested fn FUNCTION.
5377 If necessary, allocate a trampoline (in the stack frame)
5378 and emit rtl to initialize its contents (at entry to this function). */
5381 trampoline_address (function)
5387 struct function *fp;
5390 /* Find an existing trampoline and return it. */
5391 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5392 if (TREE_PURPOSE (link) == function)
5394 round_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5396 for (fp = outer_function_chain; fp; fp = fp->next)
5397 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5398 if (TREE_PURPOSE (link) == function)
5400 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5402 return round_trampoline_addr (tramp);
5405 /* None exists; we must make one. */
5407 /* Find the `struct function' for the function containing FUNCTION. */
5409 fn_context = decl_function_context (function);
5410 if (fn_context != current_function_decl
5411 && fn_context != inline_function_decl)
5412 for (fp = outer_function_chain; fp; fp = fp->next)
5413 if (fp->decl == fn_context)
5416 /* Allocate run-time space for this trampoline
5417 (usually in the defining function's stack frame). */
5418 #ifdef ALLOCATE_TRAMPOLINE
5419 tramp = ALLOCATE_TRAMPOLINE (fp);
5421 /* If rounding needed, allocate extra space
5422 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5423 #ifdef TRAMPOLINE_ALIGNMENT
5424 #define TRAMPOLINE_REAL_SIZE \
5425 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5427 #define TRAMPOLINE_REAL_SIZE (TRAMPOLINE_SIZE)
5429 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5433 /* Record the trampoline for reuse and note it for later initialization
5434 by expand_function_end. */
5437 push_obstacks (fp->function_maybepermanent_obstack,
5438 fp->function_maybepermanent_obstack);
5439 rtlexp = make_node (RTL_EXPR);
5440 RTL_EXPR_RTL (rtlexp) = tramp;
5441 fp->x_trampoline_list = tree_cons (function, rtlexp,
5442 fp->x_trampoline_list);
5447 /* Make the RTL_EXPR node temporary, not momentary, so that the
5448 trampoline_list doesn't become garbage. */
5449 int momentary = suspend_momentary ();
5450 rtlexp = make_node (RTL_EXPR);
5451 resume_momentary (momentary);
5453 RTL_EXPR_RTL (rtlexp) = tramp;
5454 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5457 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5458 return round_trampoline_addr (tramp);
5461 /* Given a trampoline address,
5462 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5465 round_trampoline_addr (tramp)
5468 #ifdef TRAMPOLINE_ALIGNMENT
5469 /* Round address up to desired boundary. */
5470 rtx temp = gen_reg_rtx (Pmode);
5471 temp = expand_binop (Pmode, add_optab, tramp,
5472 GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1),
5473 temp, 0, OPTAB_LIB_WIDEN);
5474 tramp = expand_binop (Pmode, and_optab, temp,
5475 GEN_INT (- TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT),
5476 temp, 0, OPTAB_LIB_WIDEN);
5481 /* Put all this function's BLOCK nodes including those that are chained
5482 onto the first block into a vector, and return it.
5483 Also store in each NOTE for the beginning or end of a block
5484 the index of that block in the vector.
5485 The arguments are BLOCK, the chain of top-level blocks of the function,
5486 and INSNS, the insn chain of the function. */
5492 tree *block_vector, *last_block_vector;
5494 tree block = DECL_INITIAL (current_function_decl);
5499 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5500 depth-first order. */
5501 block_vector = get_block_vector (block, &n_blocks);
5502 block_stack = (tree *) xmalloc (n_blocks * sizeof (tree));
5504 last_block_vector = identify_blocks_1 (get_insns (),
5506 block_vector + n_blocks,
5509 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5510 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5511 if (0 && last_block_vector != block_vector + n_blocks)
5514 free (block_vector);
5518 /* Subroutine of identify_blocks. Do the block substitution on the
5519 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
5521 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5522 BLOCK_VECTOR is incremented for each block seen. */
5525 identify_blocks_1 (insns, block_vector, end_block_vector, orig_block_stack)
5528 tree *end_block_vector;
5529 tree *orig_block_stack;
5532 tree *block_stack = orig_block_stack;
5534 for (insn = insns; insn; insn = NEXT_INSN (insn))
5536 if (GET_CODE (insn) == NOTE)
5538 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5542 /* If there are more block notes than BLOCKs, something
5544 if (block_vector == end_block_vector)
5547 b = *block_vector++;
5548 NOTE_BLOCK (insn) = b;
5551 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5553 /* If there are more NOTE_INSN_BLOCK_ENDs than
5554 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
5555 if (block_stack == orig_block_stack)
5558 NOTE_BLOCK (insn) = *--block_stack;
5561 else if (GET_CODE (insn) == CALL_INSN
5562 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5564 rtx cp = PATTERN (insn);
5566 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
5567 end_block_vector, block_stack);
5569 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
5570 end_block_vector, block_stack);
5572 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
5573 end_block_vector, block_stack);
5577 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
5578 something is badly wrong. */
5579 if (block_stack != orig_block_stack)
5582 return block_vector;
5585 /* Identify BLOCKs referenced by more than one
5586 NOTE_INSN_BLOCK_{BEG,END}, and create duplicate blocks. */
5591 tree block = DECL_INITIAL (current_function_decl);
5592 varray_type block_stack;
5594 if (block == NULL_TREE)
5597 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
5599 /* Prune the old trees away, so that they don't get in the way. */
5600 BLOCK_SUBBLOCKS (block) = NULL_TREE;
5601 BLOCK_CHAIN (block) = NULL_TREE;
5603 reorder_blocks_1 (get_insns (), block, &block_stack);
5605 BLOCK_SUBBLOCKS (block)
5606 = blocks_nreverse (BLOCK_SUBBLOCKS (block));
5608 VARRAY_FREE (block_stack);
5611 /* Helper function for reorder_blocks. Process the insn chain beginning
5612 at INSNS. Recurse for CALL_PLACEHOLDER insns. */
5615 reorder_blocks_1 (insns, current_block, p_block_stack)
5618 varray_type *p_block_stack;
5622 for (insn = insns; insn; insn = NEXT_INSN (insn))
5624 if (GET_CODE (insn) == NOTE)
5626 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5628 tree block = NOTE_BLOCK (insn);
5629 /* If we have seen this block before, copy it. */
5630 if (TREE_ASM_WRITTEN (block))
5632 block = copy_node (block);
5633 NOTE_BLOCK (insn) = block;
5635 BLOCK_SUBBLOCKS (block) = 0;
5636 TREE_ASM_WRITTEN (block) = 1;
5637 BLOCK_SUPERCONTEXT (block) = current_block;
5638 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
5639 BLOCK_SUBBLOCKS (current_block) = block;
5640 current_block = block;
5641 VARRAY_PUSH_TREE (*p_block_stack, block);
5643 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5645 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
5646 VARRAY_POP (*p_block_stack);
5647 BLOCK_SUBBLOCKS (current_block)
5648 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5649 current_block = BLOCK_SUPERCONTEXT (current_block);
5652 else if (GET_CODE (insn) == CALL_INSN
5653 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5655 rtx cp = PATTERN (insn);
5656 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
5658 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
5660 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
5665 /* Reverse the order of elements in the chain T of blocks,
5666 and return the new head of the chain (old last element). */
5672 register tree prev = 0, decl, next;
5673 for (decl = t; decl; decl = next)
5675 next = BLOCK_CHAIN (decl);
5676 BLOCK_CHAIN (decl) = prev;
5682 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
5683 non-NULL, list them all into VECTOR, in a depth-first preorder
5684 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
5688 all_blocks (block, vector)
5696 TREE_ASM_WRITTEN (block) = 0;
5698 /* Record this block. */
5700 vector[n_blocks] = block;
5704 /* Record the subblocks, and their subblocks... */
5705 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
5706 vector ? vector + n_blocks : 0);
5707 block = BLOCK_CHAIN (block);
5713 /* Return a vector containing all the blocks rooted at BLOCK. The
5714 number of elements in the vector is stored in N_BLOCKS_P. The
5715 vector is dynamically allocated; it is the caller's responsibility
5716 to call `free' on the pointer returned. */
5719 get_block_vector (block, n_blocks_p)
5725 *n_blocks_p = all_blocks (block, NULL);
5726 block_vector = (tree *) xmalloc (*n_blocks_p * sizeof (tree));
5727 all_blocks (block, block_vector);
5729 return block_vector;
5732 static int next_block_index = 2;
5734 /* Set BLOCK_NUMBER for all the blocks in FN. */
5744 /* For SDB and XCOFF debugging output, we start numbering the blocks
5745 from 1 within each function, rather than keeping a running
5747 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
5748 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
5749 next_block_index = 1;
5752 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
5754 /* The top-level BLOCK isn't numbered at all. */
5755 for (i = 1; i < n_blocks; ++i)
5756 /* We number the blocks from two. */
5757 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
5759 free (block_vector);
5765 /* Allocate a function structure and reset its contents to the defaults. */
5767 prepare_function_start ()
5769 cfun = (struct function *) xcalloc (1, sizeof (struct function));
5771 init_stmt_for_function ();
5772 init_eh_for_function ();
5774 cse_not_expected = ! optimize;
5776 /* Caller save not needed yet. */
5777 caller_save_needed = 0;
5779 /* No stack slots have been made yet. */
5780 stack_slot_list = 0;
5782 current_function_has_nonlocal_label = 0;
5783 current_function_has_nonlocal_goto = 0;
5785 /* There is no stack slot for handling nonlocal gotos. */
5786 nonlocal_goto_handler_slots = 0;
5787 nonlocal_goto_stack_level = 0;
5789 /* No labels have been declared for nonlocal use. */
5790 nonlocal_labels = 0;
5791 nonlocal_goto_handler_labels = 0;
5793 /* No function calls so far in this function. */
5794 function_call_count = 0;
5796 /* No parm regs have been allocated.
5797 (This is important for output_inline_function.) */
5798 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
5800 /* Initialize the RTL mechanism. */
5803 /* Initialize the queue of pending postincrement and postdecrements,
5804 and some other info in expr.c. */
5807 /* We haven't done register allocation yet. */
5810 init_varasm_status (cfun);
5812 /* Clear out data used for inlining. */
5813 cfun->inlinable = 0;
5814 cfun->original_decl_initial = 0;
5815 cfun->original_arg_vector = 0;
5817 #ifdef STACK_BOUNDARY
5818 cfun->stack_alignment_needed = STACK_BOUNDARY;
5819 cfun->preferred_stack_boundary = STACK_BOUNDARY;
5821 cfun->stack_alignment_needed = 0;
5822 cfun->preferred_stack_boundary = 0;
5825 /* Set if a call to setjmp is seen. */
5826 current_function_calls_setjmp = 0;
5828 /* Set if a call to longjmp is seen. */
5829 current_function_calls_longjmp = 0;
5831 current_function_calls_alloca = 0;
5832 current_function_contains_functions = 0;
5833 current_function_is_leaf = 0;
5834 current_function_nothrow = 0;
5835 current_function_sp_is_unchanging = 0;
5836 current_function_uses_only_leaf_regs = 0;
5837 current_function_has_computed_jump = 0;
5838 current_function_is_thunk = 0;
5840 current_function_returns_pcc_struct = 0;
5841 current_function_returns_struct = 0;
5842 current_function_epilogue_delay_list = 0;
5843 current_function_uses_const_pool = 0;
5844 current_function_uses_pic_offset_table = 0;
5845 current_function_cannot_inline = 0;
5847 /* We have not yet needed to make a label to jump to for tail-recursion. */
5848 tail_recursion_label = 0;
5850 /* We haven't had a need to make a save area for ap yet. */
5851 arg_pointer_save_area = 0;
5853 /* No stack slots allocated yet. */
5856 /* No SAVE_EXPRs in this function yet. */
5859 /* No RTL_EXPRs in this function yet. */
5862 /* Set up to allocate temporaries. */
5865 /* Indicate that we need to distinguish between the return value of the
5866 present function and the return value of a function being called. */
5867 rtx_equal_function_value_matters = 1;
5869 /* Indicate that we have not instantiated virtual registers yet. */
5870 virtuals_instantiated = 0;
5872 /* Indicate we have no need of a frame pointer yet. */
5873 frame_pointer_needed = 0;
5875 /* By default assume not varargs or stdarg. */
5876 current_function_varargs = 0;
5877 current_function_stdarg = 0;
5879 /* We haven't made any trampolines for this function yet. */
5880 trampoline_list = 0;
5882 init_pending_stack_adjust ();
5883 inhibit_defer_pop = 0;
5885 current_function_outgoing_args_size = 0;
5887 if (init_lang_status)
5888 (*init_lang_status) (cfun);
5889 if (init_machine_status)
5890 (*init_machine_status) (cfun);
5893 /* Initialize the rtl expansion mechanism so that we can do simple things
5894 like generate sequences. This is used to provide a context during global
5895 initialization of some passes. */
5897 init_dummy_function_start ()
5899 prepare_function_start ();
5902 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
5903 and initialize static variables for generating RTL for the statements
5907 init_function_start (subr, filename, line)
5909 const char *filename;
5912 prepare_function_start ();
5914 /* Remember this function for later. */
5915 cfun->next_global = all_functions;
5916 all_functions = cfun;
5918 current_function_name = (*decl_printable_name) (subr, 2);
5921 /* Nonzero if this is a nested function that uses a static chain. */
5923 current_function_needs_context
5924 = (decl_function_context (current_function_decl) != 0
5925 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
5927 /* Within function body, compute a type's size as soon it is laid out. */
5928 immediate_size_expand++;
5930 /* Prevent ever trying to delete the first instruction of a function.
5931 Also tell final how to output a linenum before the function prologue.
5932 Note linenums could be missing, e.g. when compiling a Java .class file. */
5934 emit_line_note (filename, line);
5936 /* Make sure first insn is a note even if we don't want linenums.
5937 This makes sure the first insn will never be deleted.
5938 Also, final expects a note to appear there. */
5939 emit_note (NULL_PTR, NOTE_INSN_DELETED);
5941 /* Set flags used by final.c. */
5942 if (aggregate_value_p (DECL_RESULT (subr)))
5944 #ifdef PCC_STATIC_STRUCT_RETURN
5945 current_function_returns_pcc_struct = 1;
5947 current_function_returns_struct = 1;
5950 /* Warn if this value is an aggregate type,
5951 regardless of which calling convention we are using for it. */
5952 if (warn_aggregate_return
5953 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
5954 warning ("function returns an aggregate");
5956 current_function_returns_pointer
5957 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
5960 /* Make sure all values used by the optimization passes have sane
5963 init_function_for_compilation ()
5967 /* No prologue/epilogue insns yet. */
5968 VARRAY_GROW (prologue, 0);
5969 VARRAY_GROW (epilogue, 0);
5970 VARRAY_GROW (sibcall_epilogue, 0);
5973 /* Indicate that the current function uses extra args
5974 not explicitly mentioned in the argument list in any fashion. */
5979 current_function_varargs = 1;
5982 /* Expand a call to __main at the beginning of a possible main function. */
5984 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
5985 #undef HAS_INIT_SECTION
5986 #define HAS_INIT_SECTION
5990 expand_main_function ()
5992 #if !defined (HAS_INIT_SECTION)
5993 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, NAME__MAIN), 0,
5995 #endif /* not HAS_INIT_SECTION */
5998 extern struct obstack permanent_obstack;
6000 /* Start the RTL for a new function, and set variables used for
6002 SUBR is the FUNCTION_DECL node.
6003 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6004 the function's parameters, which must be run at any return statement. */
6007 expand_function_start (subr, parms_have_cleanups)
6009 int parms_have_cleanups;
6012 rtx last_ptr = NULL_RTX;
6014 /* Make sure volatile mem refs aren't considered
6015 valid operands of arithmetic insns. */
6016 init_recog_no_volatile ();
6018 /* Set this before generating any memory accesses. */
6019 current_function_check_memory_usage
6020 = (flag_check_memory_usage
6021 && ! DECL_NO_CHECK_MEMORY_USAGE (current_function_decl));
6023 current_function_instrument_entry_exit
6024 = (flag_instrument_function_entry_exit
6025 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6027 current_function_limit_stack
6028 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6030 /* If function gets a static chain arg, store it in the stack frame.
6031 Do this first, so it gets the first stack slot offset. */
6032 if (current_function_needs_context)
6034 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
6036 /* Delay copying static chain if it is not a register to avoid
6037 conflicts with regs used for parameters. */
6038 if (! SMALL_REGISTER_CLASSES
6039 || GET_CODE (static_chain_incoming_rtx) == REG)
6040 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6043 /* If the parameters of this function need cleaning up, get a label
6044 for the beginning of the code which executes those cleanups. This must
6045 be done before doing anything with return_label. */
6046 if (parms_have_cleanups)
6047 cleanup_label = gen_label_rtx ();
6051 /* Make the label for return statements to jump to, if this machine
6052 does not have a one-instruction return and uses an epilogue,
6053 or if it returns a structure, or if it has parm cleanups. */
6055 if (cleanup_label == 0 && HAVE_return
6056 && ! current_function_instrument_entry_exit
6057 && ! current_function_returns_pcc_struct
6058 && ! (current_function_returns_struct && ! optimize))
6061 return_label = gen_label_rtx ();
6063 return_label = gen_label_rtx ();
6066 /* Initialize rtx used to return the value. */
6067 /* Do this before assign_parms so that we copy the struct value address
6068 before any library calls that assign parms might generate. */
6070 /* Decide whether to return the value in memory or in a register. */
6071 if (aggregate_value_p (DECL_RESULT (subr)))
6073 /* Returning something that won't go in a register. */
6074 register rtx value_address = 0;
6076 #ifdef PCC_STATIC_STRUCT_RETURN
6077 if (current_function_returns_pcc_struct)
6079 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6080 value_address = assemble_static_space (size);
6085 /* Expect to be passed the address of a place to store the value.
6086 If it is passed as an argument, assign_parms will take care of
6088 if (struct_value_incoming_rtx)
6090 value_address = gen_reg_rtx (Pmode);
6091 emit_move_insn (value_address, struct_value_incoming_rtx);
6096 DECL_RTL (DECL_RESULT (subr))
6097 = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
6098 set_mem_attributes (DECL_RTL (DECL_RESULT (subr)),
6099 DECL_RESULT (subr), 1);
6102 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6103 /* If return mode is void, this decl rtl should not be used. */
6104 DECL_RTL (DECL_RESULT (subr)) = 0;
6105 else if (parms_have_cleanups || current_function_instrument_entry_exit)
6107 /* If function will end with cleanup code for parms,
6108 compute the return values into a pseudo reg,
6109 which we will copy into the true return register
6110 after the cleanups are done. */
6112 enum machine_mode mode = DECL_MODE (DECL_RESULT (subr));
6114 #ifdef PROMOTE_FUNCTION_RETURN
6115 tree type = TREE_TYPE (DECL_RESULT (subr));
6116 int unsignedp = TREE_UNSIGNED (type);
6118 mode = promote_mode (type, mode, &unsignedp, 1);
6121 DECL_RTL (DECL_RESULT (subr)) = gen_reg_rtx (mode);
6124 /* Scalar, returned in a register. */
6126 DECL_RTL (DECL_RESULT (subr))
6127 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)), subr, 1);
6129 /* Mark this reg as the function's return value. */
6130 if (GET_CODE (DECL_RTL (DECL_RESULT (subr))) == REG)
6132 REG_FUNCTION_VALUE_P (DECL_RTL (DECL_RESULT (subr))) = 1;
6133 /* Needed because we may need to move this to memory
6134 in case it's a named return value whose address is taken. */
6135 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6139 /* Initialize rtx for parameters and local variables.
6140 In some cases this requires emitting insns. */
6142 assign_parms (subr);
6144 /* Copy the static chain now if it wasn't a register. The delay is to
6145 avoid conflicts with the parameter passing registers. */
6147 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6148 if (GET_CODE (static_chain_incoming_rtx) != REG)
6149 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6151 /* The following was moved from init_function_start.
6152 The move is supposed to make sdb output more accurate. */
6153 /* Indicate the beginning of the function body,
6154 as opposed to parm setup. */
6155 emit_note (NULL_PTR, NOTE_INSN_FUNCTION_BEG);
6157 if (GET_CODE (get_last_insn ()) != NOTE)
6158 emit_note (NULL_PTR, NOTE_INSN_DELETED);
6159 parm_birth_insn = get_last_insn ();
6161 context_display = 0;
6162 if (current_function_needs_context)
6164 /* Fetch static chain values for containing functions. */
6165 tem = decl_function_context (current_function_decl);
6166 /* Copy the static chain pointer into a pseudo. If we have
6167 small register classes, copy the value from memory if
6168 static_chain_incoming_rtx is a REG. */
6171 /* If the static chain originally came in a register, put it back
6172 there, then move it out in the next insn. The reason for
6173 this peculiar code is to satisfy function integration. */
6174 if (SMALL_REGISTER_CLASSES
6175 && GET_CODE (static_chain_incoming_rtx) == REG)
6176 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6177 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6182 tree rtlexp = make_node (RTL_EXPR);
6184 RTL_EXPR_RTL (rtlexp) = last_ptr;
6185 context_display = tree_cons (tem, rtlexp, context_display);
6186 tem = decl_function_context (tem);
6189 /* Chain thru stack frames, assuming pointer to next lexical frame
6190 is found at the place we always store it. */
6191 #ifdef FRAME_GROWS_DOWNWARD
6192 last_ptr = plus_constant (last_ptr, - GET_MODE_SIZE (Pmode));
6194 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr));
6195 MEM_ALIAS_SET (last_ptr) = get_frame_alias_set ();
6196 last_ptr = copy_to_reg (last_ptr);
6198 /* If we are not optimizing, ensure that we know that this
6199 piece of context is live over the entire function. */
6201 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6206 if (current_function_instrument_entry_exit)
6208 rtx fun = DECL_RTL (current_function_decl);
6209 if (GET_CODE (fun) == MEM)
6210 fun = XEXP (fun, 0);
6213 emit_library_call (profile_function_entry_libfunc, 0, VOIDmode, 2,
6215 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6217 hard_frame_pointer_rtx),
6221 /* After the display initializations is where the tail-recursion label
6222 should go, if we end up needing one. Ensure we have a NOTE here
6223 since some things (like trampolines) get placed before this. */
6224 tail_recursion_reentry = emit_note (NULL_PTR, NOTE_INSN_DELETED);
6226 /* Evaluate now the sizes of any types declared among the arguments. */
6227 for (tem = nreverse (get_pending_sizes ()); tem; tem = TREE_CHAIN (tem))
6229 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode,
6230 EXPAND_MEMORY_USE_BAD);
6231 /* Flush the queue in case this parameter declaration has
6236 /* Make sure there is a line number after the function entry setup code. */
6237 force_next_line_note ();
6240 /* Undo the effects of init_dummy_function_start. */
6242 expand_dummy_function_end ()
6244 /* End any sequences that failed to be closed due to syntax errors. */
6245 while (in_sequence_p ())
6248 /* Outside function body, can't compute type's actual size
6249 until next function's body starts. */
6251 free_after_parsing (cfun);
6252 free_after_compilation (cfun);
6257 /* Call DOIT for each hard register used as a return value from
6258 the current function. */
6261 diddle_return_value (doit, arg)
6262 void (*doit) PARAMS ((rtx, void *));
6265 rtx outgoing = current_function_return_rtx;
6271 pcc = (current_function_returns_struct
6272 || current_function_returns_pcc_struct);
6274 if ((GET_CODE (outgoing) == REG
6275 && REGNO (outgoing) >= FIRST_PSEUDO_REGISTER)
6278 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
6280 /* A PCC-style return returns a pointer to the memory in which
6281 the structure is stored. */
6283 type = build_pointer_type (type);
6285 #ifdef FUNCTION_OUTGOING_VALUE
6286 outgoing = FUNCTION_OUTGOING_VALUE (type, current_function_decl);
6288 outgoing = FUNCTION_VALUE (type, current_function_decl);
6290 /* If this is a BLKmode structure being returned in registers, then use
6291 the mode computed in expand_return. */
6292 if (GET_MODE (outgoing) == BLKmode)
6294 GET_MODE (DECL_RTL (DECL_RESULT (current_function_decl))));
6295 REG_FUNCTION_VALUE_P (outgoing) = 1;
6298 if (GET_CODE (outgoing) == REG)
6299 (*doit) (outgoing, arg);
6300 else if (GET_CODE (outgoing) == PARALLEL)
6304 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6306 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6308 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6315 do_clobber_return_reg (reg, arg)
6317 void *arg ATTRIBUTE_UNUSED;
6319 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6323 clobber_return_register ()
6325 diddle_return_value (do_clobber_return_reg, NULL);
6329 do_use_return_reg (reg, arg)
6331 void *arg ATTRIBUTE_UNUSED;
6333 emit_insn (gen_rtx_USE (VOIDmode, reg));
6337 use_return_register ()
6339 diddle_return_value (do_use_return_reg, NULL);
6342 /* Generate RTL for the end of the current function.
6343 FILENAME and LINE are the current position in the source file.
6345 It is up to language-specific callers to do cleanups for parameters--
6346 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
6349 expand_function_end (filename, line, end_bindings)
6350 const char *filename;
6356 #ifdef TRAMPOLINE_TEMPLATE
6357 static rtx initial_trampoline;
6360 finish_expr_for_function ();
6362 #ifdef NON_SAVING_SETJMP
6363 /* Don't put any variables in registers if we call setjmp
6364 on a machine that fails to restore the registers. */
6365 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6367 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6368 setjmp_protect (DECL_INITIAL (current_function_decl));
6370 setjmp_protect_args ();
6374 /* Save the argument pointer if a save area was made for it. */
6375 if (arg_pointer_save_area)
6377 /* arg_pointer_save_area may not be a valid memory address, so we
6378 have to check it and fix it if necessary. */
6381 emit_move_insn (validize_mem (arg_pointer_save_area),
6382 virtual_incoming_args_rtx);
6383 seq = gen_sequence ();
6385 emit_insn_before (seq, tail_recursion_reentry);
6388 /* Initialize any trampolines required by this function. */
6389 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6391 tree function = TREE_PURPOSE (link);
6392 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6393 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6394 #ifdef TRAMPOLINE_TEMPLATE
6399 #ifdef TRAMPOLINE_TEMPLATE
6400 /* First make sure this compilation has a template for
6401 initializing trampolines. */
6402 if (initial_trampoline == 0)
6404 end_temporary_allocation ();
6406 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6407 resume_temporary_allocation ();
6409 ggc_add_rtx_root (&initial_trampoline, 1);
6413 /* Generate insns to initialize the trampoline. */
6415 tramp = round_trampoline_addr (XEXP (tramp, 0));
6416 #ifdef TRAMPOLINE_TEMPLATE
6417 blktramp = change_address (initial_trampoline, BLKmode, tramp);
6418 emit_block_move (blktramp, initial_trampoline,
6419 GEN_INT (TRAMPOLINE_SIZE),
6420 TRAMPOLINE_ALIGNMENT);
6422 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6426 /* Put those insns at entry to the containing function (this one). */
6427 emit_insns_before (seq, tail_recursion_reentry);
6430 /* If we are doing stack checking and this function makes calls,
6431 do a stack probe at the start of the function to ensure we have enough
6432 space for another stack frame. */
6433 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6437 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6438 if (GET_CODE (insn) == CALL_INSN)
6441 probe_stack_range (STACK_CHECK_PROTECT,
6442 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6445 emit_insns_before (seq, tail_recursion_reentry);
6450 /* Warn about unused parms if extra warnings were specified. */
6451 /* Either ``-W -Wunused'' or ``-Wunused-parameter'' enables this
6452 warning. WARN_UNUSED_PARAMETER is negative when set by
6454 if (warn_unused_parameter > 0
6455 || (warn_unused_parameter < 0 && extra_warnings))
6459 for (decl = DECL_ARGUMENTS (current_function_decl);
6460 decl; decl = TREE_CHAIN (decl))
6461 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6462 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6463 warning_with_decl (decl, "unused parameter `%s'");
6466 /* Delete handlers for nonlocal gotos if nothing uses them. */
6467 if (nonlocal_goto_handler_slots != 0
6468 && ! current_function_has_nonlocal_label)
6471 /* End any sequences that failed to be closed due to syntax errors. */
6472 while (in_sequence_p ())
6475 /* Outside function body, can't compute type's actual size
6476 until next function's body starts. */
6477 immediate_size_expand--;
6479 clear_pending_stack_adjust ();
6480 do_pending_stack_adjust ();
6482 /* Mark the end of the function body.
6483 If control reaches this insn, the function can drop through
6484 without returning a value. */
6485 emit_note (NULL_PTR, NOTE_INSN_FUNCTION_END);
6487 /* Must mark the last line number note in the function, so that the test
6488 coverage code can avoid counting the last line twice. This just tells
6489 the code to ignore the immediately following line note, since there
6490 already exists a copy of this note somewhere above. This line number
6491 note is still needed for debugging though, so we can't delete it. */
6492 if (flag_test_coverage)
6493 emit_note (NULL_PTR, NOTE_INSN_REPEATED_LINE_NUMBER);
6495 /* Output a linenumber for the end of the function.
6496 SDB depends on this. */
6497 emit_line_note_force (filename, line);
6499 /* Output the label for the actual return from the function,
6500 if one is expected. This happens either because a function epilogue
6501 is used instead of a return instruction, or because a return was done
6502 with a goto in order to run local cleanups, or because of pcc-style
6503 structure returning. */
6507 /* Before the return label, clobber the return registers so that
6508 they are not propogated live to the rest of the function. This
6509 can only happen with functions that drop through; if there had
6510 been a return statement, there would have either been a return
6511 rtx, or a jump to the return label. */
6512 clobber_return_register ();
6514 emit_label (return_label);
6517 /* C++ uses this. */
6519 expand_end_bindings (0, 0, 0);
6521 /* Now handle any leftover exception regions that may have been
6522 created for the parameters. */
6524 rtx last = get_last_insn ();
6527 expand_leftover_cleanups ();
6529 /* If there are any catch_clauses remaining, output them now. */
6530 emit_insns (catch_clauses);
6531 catch_clauses = catch_clauses_last = NULL_RTX;
6532 /* If the above emitted any code, may sure we jump around it. */
6533 if (last != get_last_insn ())
6535 label = gen_label_rtx ();
6536 last = emit_jump_insn_after (gen_jump (label), last);
6537 last = emit_barrier_after (last);
6542 if (current_function_instrument_entry_exit)
6544 rtx fun = DECL_RTL (current_function_decl);
6545 if (GET_CODE (fun) == MEM)
6546 fun = XEXP (fun, 0);
6549 emit_library_call (profile_function_exit_libfunc, 0, VOIDmode, 2,
6551 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6553 hard_frame_pointer_rtx),
6557 /* If we had calls to alloca, and this machine needs
6558 an accurate stack pointer to exit the function,
6559 insert some code to save and restore the stack pointer. */
6560 #ifdef EXIT_IGNORE_STACK
6561 if (! EXIT_IGNORE_STACK)
6563 if (current_function_calls_alloca)
6567 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
6568 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
6571 /* If scalar return value was computed in a pseudo-reg,
6572 copy that to the hard return register. */
6573 if (DECL_RTL (DECL_RESULT (current_function_decl)) != 0
6574 && GET_CODE (DECL_RTL (DECL_RESULT (current_function_decl))) == REG
6575 && (REGNO (DECL_RTL (DECL_RESULT (current_function_decl)))
6576 >= FIRST_PSEUDO_REGISTER))
6578 rtx real_decl_result;
6580 #ifdef FUNCTION_OUTGOING_VALUE
6582 = FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl)),
6583 current_function_decl);
6586 = FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl)),
6587 current_function_decl);
6589 REG_FUNCTION_VALUE_P (real_decl_result) = 1;
6590 /* If this is a BLKmode structure being returned in registers, then use
6591 the mode computed in expand_return. */
6592 if (GET_MODE (real_decl_result) == BLKmode)
6593 PUT_MODE (real_decl_result,
6594 GET_MODE (DECL_RTL (DECL_RESULT (current_function_decl))));
6595 emit_move_insn (real_decl_result,
6596 DECL_RTL (DECL_RESULT (current_function_decl)));
6598 /* The delay slot scheduler assumes that current_function_return_rtx
6599 holds the hard register containing the return value, not a temporary
6601 current_function_return_rtx = real_decl_result;
6604 /* If returning a structure, arrange to return the address of the value
6605 in a place where debuggers expect to find it.
6607 If returning a structure PCC style,
6608 the caller also depends on this value.
6609 And current_function_returns_pcc_struct is not necessarily set. */
6610 if (current_function_returns_struct
6611 || current_function_returns_pcc_struct)
6613 rtx value_address = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
6614 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
6615 #ifdef FUNCTION_OUTGOING_VALUE
6617 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
6618 current_function_decl);
6621 = FUNCTION_VALUE (build_pointer_type (type),
6622 current_function_decl);
6625 /* Mark this as a function return value so integrate will delete the
6626 assignment and USE below when inlining this function. */
6627 REG_FUNCTION_VALUE_P (outgoing) = 1;
6629 emit_move_insn (outgoing, value_address);
6632 /* ??? This should no longer be necessary since stupid is no longer with
6633 us, but there are some parts of the compiler (eg reload_combine, and
6634 sh mach_dep_reorg) that still try and compute their own lifetime info
6635 instead of using the general framework. */
6636 use_return_register ();
6638 /* If this is an implementation of __throw, do what's necessary to
6639 communicate between __builtin_eh_return and the epilogue. */
6640 expand_eh_return ();
6642 /* Output a return insn if we are using one.
6643 Otherwise, let the rtl chain end here, to drop through
6644 into the epilogue. */
6649 emit_jump_insn (gen_return ());
6654 /* Fix up any gotos that jumped out to the outermost
6655 binding level of the function.
6656 Must follow emitting RETURN_LABEL. */
6658 /* If you have any cleanups to do at this point,
6659 and they need to create temporary variables,
6660 then you will lose. */
6661 expand_fixups (get_insns ());
6664 /* Extend a vector that records the INSN_UIDs of INSNS (either a
6665 sequence or a single insn). */
6668 record_insns (insns, vecp)
6672 if (GET_CODE (insns) == SEQUENCE)
6674 int len = XVECLEN (insns, 0);
6675 int i = VARRAY_SIZE (*vecp);
6677 VARRAY_GROW (*vecp, i + len);
6680 VARRAY_INT (*vecp, i) = INSN_UID (XVECEXP (insns, 0, len));
6686 int i = VARRAY_SIZE (*vecp);
6687 VARRAY_GROW (*vecp, i + 1);
6688 VARRAY_INT (*vecp, i) = INSN_UID (insns);
6692 /* Determine how many INSN_UIDs in VEC are part of INSN. */
6695 contains (insn, vec)
6701 if (GET_CODE (insn) == INSN
6702 && GET_CODE (PATTERN (insn)) == SEQUENCE)
6705 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
6706 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
6707 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
6713 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
6714 if (INSN_UID (insn) == VARRAY_INT (vec, j))
6721 prologue_epilogue_contains (insn)
6724 if (contains (insn, prologue))
6726 if (contains (insn, epilogue))
6732 sibcall_epilogue_contains (insn)
6735 if (sibcall_epilogue)
6736 return contains (insn, sibcall_epilogue);
6741 /* Insert gen_return at the end of block BB. This also means updating
6742 block_for_insn appropriately. */
6745 emit_return_into_block (bb, line_note)
6751 p = NEXT_INSN (bb->end);
6752 end = emit_jump_insn_after (gen_return (), bb->end);
6754 emit_line_note_after (NOTE_SOURCE_FILE (line_note),
6755 NOTE_LINE_NUMBER (line_note), bb->end);
6759 set_block_for_insn (p, bb);
6766 #endif /* HAVE_return */
6768 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
6769 this into place with notes indicating where the prologue ends and where
6770 the epilogue begins. Update the basic block information when possible. */
6773 thread_prologue_and_epilogue_insns (f)
6774 rtx f ATTRIBUTE_UNUSED;
6779 #ifdef HAVE_prologue
6780 rtx prologue_end = NULL_RTX;
6782 #if defined (HAVE_epilogue) || defined(HAVE_return)
6783 rtx epilogue_end = NULL_RTX;
6786 #ifdef HAVE_prologue
6790 seq = gen_prologue();
6793 /* Retain a map of the prologue insns. */
6794 if (GET_CODE (seq) != SEQUENCE)
6796 record_insns (seq, &prologue);
6797 prologue_end = emit_note (NULL, NOTE_INSN_PROLOGUE_END);
6799 seq = gen_sequence ();
6802 /* If optimization is off, and perhaps in an empty function,
6803 the entry block will have no successors. */
6804 if (ENTRY_BLOCK_PTR->succ)
6806 /* Can't deal with multiple successsors of the entry block. */
6807 if (ENTRY_BLOCK_PTR->succ->succ_next)
6810 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
6814 emit_insn_after (seq, f);
6818 /* If the exit block has no non-fake predecessors, we don't need
6820 for (e = EXIT_BLOCK_PTR->pred; e ; e = e->pred_next)
6821 if ((e->flags & EDGE_FAKE) == 0)
6827 if (optimize && HAVE_return)
6829 /* If we're allowed to generate a simple return instruction,
6830 then by definition we don't need a full epilogue. Examine
6831 the block that falls through to EXIT. If it does not
6832 contain any code, examine its predecessors and try to
6833 emit (conditional) return instructions. */
6839 for (e = EXIT_BLOCK_PTR->pred; e ; e = e->pred_next)
6840 if (e->flags & EDGE_FALLTHRU)
6846 /* Verify that there are no active instructions in the last block. */
6848 while (label && GET_CODE (label) != CODE_LABEL)
6850 if (active_insn_p (label))
6852 label = PREV_INSN (label);
6855 if (last->head == label && GET_CODE (label) == CODE_LABEL)
6857 rtx epilogue_line_note = NULL_RTX;
6859 /* Locate the line number associated with the closing brace,
6860 if we can find one. */
6861 for (seq = get_last_insn ();
6862 seq && ! active_insn_p (seq);
6863 seq = PREV_INSN (seq))
6864 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
6866 epilogue_line_note = seq;
6870 for (e = last->pred; e ; e = e_next)
6872 basic_block bb = e->src;
6875 e_next = e->pred_next;
6876 if (bb == ENTRY_BLOCK_PTR)
6880 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
6883 /* If we have an unconditional jump, we can replace that
6884 with a simple return instruction. */
6885 if (simplejump_p (jump))
6887 emit_return_into_block (bb, epilogue_line_note);
6888 flow_delete_insn (jump);
6891 /* If we have a conditional jump, we can try to replace
6892 that with a conditional return instruction. */
6893 else if (condjump_p (jump))
6897 ret = SET_SRC (PATTERN (jump));
6898 if (GET_CODE (XEXP (ret, 1)) == LABEL_REF)
6899 loc = &XEXP (ret, 1);
6901 loc = &XEXP (ret, 2);
6902 ret = gen_rtx_RETURN (VOIDmode);
6904 if (! validate_change (jump, loc, ret, 0))
6906 if (JUMP_LABEL (jump))
6907 LABEL_NUSES (JUMP_LABEL (jump))--;
6909 /* If this block has only one successor, it both jumps
6910 and falls through to the fallthru block, so we can't
6912 if (bb->succ->succ_next == NULL)
6918 /* Fix up the CFG for the successful change we just made. */
6919 redirect_edge_succ (e, EXIT_BLOCK_PTR);
6922 /* Emit a return insn for the exit fallthru block. Whether
6923 this is still reachable will be determined later. */
6925 emit_barrier_after (last->end);
6926 emit_return_into_block (last, epilogue_line_note);
6927 epilogue_end = last->end;
6932 #ifdef HAVE_epilogue
6935 /* Find the edge that falls through to EXIT. Other edges may exist
6936 due to RETURN instructions, but those don't need epilogues.
6937 There really shouldn't be a mixture -- either all should have
6938 been converted or none, however... */
6940 for (e = EXIT_BLOCK_PTR->pred; e ; e = e->pred_next)
6941 if (e->flags & EDGE_FALLTHRU)
6947 epilogue_end = emit_note (NULL, NOTE_INSN_EPILOGUE_BEG);
6949 seq = gen_epilogue ();
6950 emit_jump_insn (seq);
6952 /* Retain a map of the epilogue insns. */
6953 if (GET_CODE (seq) != SEQUENCE)
6955 record_insns (seq, &epilogue);
6957 seq = gen_sequence ();
6960 insert_insn_on_edge (seq, e);
6967 commit_edge_insertions ();
6969 #ifdef HAVE_sibcall_epilogue
6970 /* Emit sibling epilogues before any sibling call sites. */
6971 for (e = EXIT_BLOCK_PTR->pred; e ; e = e->pred_next)
6973 basic_block bb = e->src;
6978 if (GET_CODE (insn) != CALL_INSN
6979 || ! SIBLING_CALL_P (insn))
6983 seq = gen_sibcall_epilogue ();
6986 i = PREV_INSN (insn);
6987 newinsn = emit_insn_before (seq, insn);
6989 /* Update the UID to basic block map. */
6990 for (i = NEXT_INSN (i); i != insn; i = NEXT_INSN (i))
6991 set_block_for_insn (i, bb);
6993 /* Retain a map of the epilogue insns. Used in life analysis to
6994 avoid getting rid of sibcall epilogue insns. */
6995 record_insns (GET_CODE (seq) == SEQUENCE
6996 ? seq : newinsn, &sibcall_epilogue);
7000 #ifdef HAVE_prologue
7005 /* GDB handles `break f' by setting a breakpoint on the first
7006 line note after the prologue. Which means (1) that if
7007 there are line number notes before where we inserted the
7008 prologue we should move them, and (2) we should generate a
7009 note before the end of the first basic block, if there isn't
7010 one already there. */
7012 for (insn = prologue_end; insn ; insn = prev)
7014 prev = PREV_INSN (insn);
7015 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7017 /* Note that we cannot reorder the first insn in the
7018 chain, since rest_of_compilation relies on that
7019 remaining constant. */
7022 reorder_insns (insn, insn, prologue_end);
7026 /* Find the last line number note in the first block. */
7027 for (insn = BASIC_BLOCK (0)->end;
7028 insn != prologue_end;
7029 insn = PREV_INSN (insn))
7030 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7033 /* If we didn't find one, make a copy of the first line number
7037 for (insn = next_active_insn (prologue_end);
7039 insn = PREV_INSN (insn))
7040 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7042 emit_line_note_after (NOTE_SOURCE_FILE (insn),
7043 NOTE_LINE_NUMBER (insn),
7050 #ifdef HAVE_epilogue
7055 /* Similarly, move any line notes that appear after the epilogue.
7056 There is no need, however, to be quite so anal about the existance
7058 for (insn = epilogue_end; insn ; insn = next)
7060 next = NEXT_INSN (insn);
7061 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7062 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7068 /* Reposition the prologue-end and epilogue-begin notes after instruction
7069 scheduling and delayed branch scheduling. */
7072 reposition_prologue_and_epilogue_notes (f)
7073 rtx f ATTRIBUTE_UNUSED;
7075 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7078 if ((len = VARRAY_SIZE (prologue)) > 0)
7080 register rtx insn, note = 0;
7082 /* Scan from the beginning until we reach the last prologue insn.
7083 We apparently can't depend on basic_block_{head,end} after
7085 for (insn = f; len && insn; insn = NEXT_INSN (insn))
7087 if (GET_CODE (insn) == NOTE)
7089 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
7092 else if ((len -= contains (insn, prologue)) == 0)
7095 /* Find the prologue-end note if we haven't already, and
7096 move it to just after the last prologue insn. */
7099 for (note = insn; (note = NEXT_INSN (note));)
7100 if (GET_CODE (note) == NOTE
7101 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
7105 next = NEXT_INSN (note);
7107 /* Whether or not we can depend on BLOCK_HEAD,
7108 attempt to keep it up-to-date. */
7109 if (BLOCK_HEAD (0) == note)
7110 BLOCK_HEAD (0) = next;
7113 add_insn_after (note, insn);
7118 if ((len = VARRAY_SIZE (epilogue)) > 0)
7120 register rtx insn, note = 0;
7122 /* Scan from the end until we reach the first epilogue insn.
7123 We apparently can't depend on basic_block_{head,end} after
7125 for (insn = get_last_insn (); len && insn; insn = PREV_INSN (insn))
7127 if (GET_CODE (insn) == NOTE)
7129 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
7132 else if ((len -= contains (insn, epilogue)) == 0)
7134 /* Find the epilogue-begin note if we haven't already, and
7135 move it to just before the first epilogue insn. */
7138 for (note = insn; (note = PREV_INSN (note));)
7139 if (GET_CODE (note) == NOTE
7140 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
7144 /* Whether or not we can depend on BLOCK_HEAD,
7145 attempt to keep it up-to-date. */
7147 && BLOCK_HEAD (n_basic_blocks-1) == insn)
7148 BLOCK_HEAD (n_basic_blocks-1) = note;
7151 add_insn_before (note, insn);
7155 #endif /* HAVE_prologue or HAVE_epilogue */
7158 /* Mark T for GC. */
7162 struct temp_slot *t;
7166 ggc_mark_rtx (t->slot);
7167 ggc_mark_rtx (t->address);
7168 ggc_mark_tree (t->rtl_expr);
7174 /* Mark P for GC. */
7177 mark_function_status (p)
7186 ggc_mark_rtx (p->arg_offset_rtx);
7188 if (p->x_parm_reg_stack_loc)
7189 for (i = p->x_max_parm_reg, r = p->x_parm_reg_stack_loc;
7193 ggc_mark_rtx (p->return_rtx);
7194 ggc_mark_rtx (p->x_cleanup_label);
7195 ggc_mark_rtx (p->x_return_label);
7196 ggc_mark_rtx (p->x_save_expr_regs);
7197 ggc_mark_rtx (p->x_stack_slot_list);
7198 ggc_mark_rtx (p->x_parm_birth_insn);
7199 ggc_mark_rtx (p->x_tail_recursion_label);
7200 ggc_mark_rtx (p->x_tail_recursion_reentry);
7201 ggc_mark_rtx (p->internal_arg_pointer);
7202 ggc_mark_rtx (p->x_arg_pointer_save_area);
7203 ggc_mark_tree (p->x_rtl_expr_chain);
7204 ggc_mark_rtx (p->x_last_parm_insn);
7205 ggc_mark_tree (p->x_context_display);
7206 ggc_mark_tree (p->x_trampoline_list);
7207 ggc_mark_rtx (p->epilogue_delay_list);
7209 mark_temp_slot (p->x_temp_slots);
7212 struct var_refs_queue *q = p->fixup_var_refs_queue;
7215 ggc_mark_rtx (q->modified);
7220 ggc_mark_rtx (p->x_nonlocal_goto_handler_slots);
7221 ggc_mark_rtx (p->x_nonlocal_goto_handler_labels);
7222 ggc_mark_rtx (p->x_nonlocal_goto_stack_level);
7223 ggc_mark_tree (p->x_nonlocal_labels);
7226 /* Mark the function chain ARG (which is really a struct function **)
7230 mark_function_chain (arg)
7233 struct function *f = *(struct function **) arg;
7235 for (; f; f = f->next_global)
7237 ggc_mark_tree (f->decl);
7239 mark_function_status (f);
7240 mark_eh_status (f->eh);
7241 mark_stmt_status (f->stmt);
7242 mark_expr_status (f->expr);
7243 mark_emit_status (f->emit);
7244 mark_varasm_status (f->varasm);
7246 if (mark_machine_status)
7247 (*mark_machine_status) (f);
7248 if (mark_lang_status)
7249 (*mark_lang_status) (f);
7251 if (f->original_arg_vector)
7252 ggc_mark_rtvec ((rtvec) f->original_arg_vector);
7253 if (f->original_decl_initial)
7254 ggc_mark_tree (f->original_decl_initial);
7258 /* Called once, at initialization, to initialize function.c. */
7261 init_function_once ()
7263 ggc_add_root (&all_functions, 1, sizeof all_functions,
7264 mark_function_chain);
7266 VARRAY_INT_INIT (prologue, 0, "prologue");
7267 VARRAY_INT_INIT (epilogue, 0, "epilogue");
7268 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");