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. */
22 /* This file handles the generation of rtl code from tree structure
23 at the level of the function as a whole.
24 It creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 `expand_function_start' is called at the beginning of a function,
28 before the function body is parsed, and `expand_function_end' is
29 called after parsing the body.
31 Call `assign_stack_local' to allocate a stack slot for a local variable.
32 This is usually done during the RTL generation for the function body,
33 but it can also be done in the reload pass when a pseudo-register does
34 not get a hard register.
36 Call `put_var_into_stack' when you learn, belatedly, that a variable
37 previously given a pseudo-register must in fact go in the stack.
38 This function changes the DECL_RTL to be a stack slot instead of a reg
39 then scans all the RTL instructions so far generated to correct them. */
48 #include "insn-flags.h"
50 #include "insn-codes.h"
52 #include "hard-reg-set.h"
53 #include "insn-config.h"
56 #include "basic-block.h"
63 #ifndef ACCUMULATE_OUTGOING_ARGS
64 #define ACCUMULATE_OUTGOING_ARGS 0
67 #ifndef TRAMPOLINE_ALIGNMENT
68 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
71 #ifndef LOCAL_ALIGNMENT
72 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
75 #if !defined (PREFERRED_STACK_BOUNDARY) && defined (STACK_BOUNDARY)
76 #define PREFERRED_STACK_BOUNDARY STACK_BOUNDARY
79 /* Some systems use __main in a way incompatible with its use in gcc, in these
80 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
81 give the same symbol without quotes for an alternative entry point. You
82 must define both, or neither. */
84 #define NAME__MAIN "__main"
85 #define SYMBOL__MAIN __main
88 /* Round a value to the lowest integer less than it that is a multiple of
89 the required alignment. Avoid using division in case the value is
90 negative. Assume the alignment is a power of two. */
91 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
93 /* Similar, but round to the next highest integer that meets the
95 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
97 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
98 during rtl generation. If they are different register numbers, this is
99 always true. It may also be true if
100 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
101 generation. See fix_lexical_addr for details. */
103 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
104 #define NEED_SEPARATE_AP
107 /* Nonzero if function being compiled doesn't contain any calls
108 (ignoring the prologue and epilogue). This is set prior to
109 local register allocation and is valid for the remaining
111 int current_function_is_leaf;
113 /* Nonzero if function being compiled doesn't contain any instructions
114 that can throw an exception. This is set prior to final. */
116 int current_function_nothrow;
118 /* Nonzero if function being compiled doesn't modify the stack pointer
119 (ignoring the prologue and epilogue). This is only valid after
120 life_analysis has run. */
121 int current_function_sp_is_unchanging;
123 /* Nonzero if the function being compiled is a leaf function which only
124 uses leaf registers. This is valid after reload (specifically after
125 sched2) and is useful only if the port defines LEAF_REGISTERS. */
126 int current_function_uses_only_leaf_regs;
128 /* Nonzero once virtual register instantiation has been done.
129 assign_stack_local uses frame_pointer_rtx when this is nonzero. */
130 static int virtuals_instantiated;
132 /* These variables hold pointers to functions to
133 save and restore machine-specific data,
134 in push_function_context and pop_function_context. */
135 void (*init_machine_status) PARAMS ((struct function *));
136 void (*save_machine_status) PARAMS ((struct function *));
137 void (*restore_machine_status) PARAMS ((struct function *));
138 void (*mark_machine_status) PARAMS ((struct function *));
139 void (*free_machine_status) PARAMS ((struct function *));
141 /* Likewise, but for language-specific data. */
142 void (*init_lang_status) PARAMS ((struct function *));
143 void (*save_lang_status) PARAMS ((struct function *));
144 void (*restore_lang_status) PARAMS ((struct function *));
145 void (*mark_lang_status) PARAMS ((struct function *));
146 void (*free_lang_status) PARAMS ((struct function *));
148 /* The FUNCTION_DECL for an inline function currently being expanded. */
149 tree inline_function_decl;
151 /* The currently compiled function. */
152 struct function *cfun = 0;
154 /* Global list of all compiled functions. */
155 struct function *all_functions = 0;
157 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
158 static varray_type prologue;
159 static varray_type epilogue;
161 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
163 static varray_type sibcall_epilogue;
165 /* In order to evaluate some expressions, such as function calls returning
166 structures in memory, we need to temporarily allocate stack locations.
167 We record each allocated temporary in the following structure.
169 Associated with each temporary slot is a nesting level. When we pop up
170 one level, all temporaries associated with the previous level are freed.
171 Normally, all temporaries are freed after the execution of the statement
172 in which they were created. However, if we are inside a ({...}) grouping,
173 the result may be in a temporary and hence must be preserved. If the
174 result could be in a temporary, we preserve it if we can determine which
175 one it is in. If we cannot determine which temporary may contain the
176 result, all temporaries are preserved. A temporary is preserved by
177 pretending it was allocated at the previous nesting level.
179 Automatic variables are also assigned temporary slots, at the nesting
180 level where they are defined. They are marked a "kept" so that
181 free_temp_slots will not free them. */
185 /* Points to next temporary slot. */
186 struct temp_slot *next;
187 /* The rtx to used to reference the slot. */
189 /* The rtx used to represent the address if not the address of the
190 slot above. May be an EXPR_LIST if multiple addresses exist. */
192 /* The alignment (in bits) of the slot. */
194 /* The size, in units, of the slot. */
196 /* The alias set for the slot. If the alias set is zero, we don't
197 know anything about the alias set of the slot. We must only
198 reuse a slot if it is assigned an object of the same alias set.
199 Otherwise, the rest of the compiler may assume that the new use
200 of the slot cannot alias the old use of the slot, which is
201 false. If the slot has alias set zero, then we can't reuse the
202 slot at all, since we have no idea what alias set may have been
203 imposed on the memory. For example, if the stack slot is the
204 call frame for an inline functioned, we have no idea what alias
205 sets will be assigned to various pieces of the call frame. */
206 HOST_WIDE_INT alias_set;
207 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
209 /* Non-zero if this temporary is currently in use. */
211 /* Non-zero if this temporary has its address taken. */
213 /* Nesting level at which this slot is being used. */
215 /* Non-zero if this should survive a call to free_temp_slots. */
217 /* The offset of the slot from the frame_pointer, including extra space
218 for alignment. This info is for combine_temp_slots. */
219 HOST_WIDE_INT base_offset;
220 /* The size of the slot, including extra space for alignment. This
221 info is for combine_temp_slots. */
222 HOST_WIDE_INT full_size;
225 /* This structure is used to record MEMs or pseudos used to replace VAR, any
226 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
227 maintain this list in case two operands of an insn were required to match;
228 in that case we must ensure we use the same replacement. */
230 struct fixup_replacement
234 struct fixup_replacement *next;
237 struct insns_for_mem_entry {
238 /* The KEY in HE will be a MEM. */
239 struct hash_entry he;
240 /* These are the INSNS which reference the MEM. */
244 /* Forward declarations. */
246 static rtx assign_stack_local_1 PARAMS ((enum machine_mode, HOST_WIDE_INT,
247 int, struct function *));
248 static rtx assign_stack_temp_for_type PARAMS ((enum machine_mode,
249 HOST_WIDE_INT, int, tree));
250 static struct temp_slot *find_temp_slot_from_address PARAMS ((rtx));
251 static void put_reg_into_stack PARAMS ((struct function *, rtx, tree,
252 enum machine_mode, enum machine_mode,
253 int, unsigned int, int,
254 struct hash_table *));
255 static void schedule_fixup_var_refs PARAMS ((struct function *, rtx, tree,
257 struct hash_table *));
258 static void fixup_var_refs PARAMS ((rtx, enum machine_mode, int,
259 struct hash_table *));
260 static struct fixup_replacement
261 *find_fixup_replacement PARAMS ((struct fixup_replacement **, rtx));
262 static void fixup_var_refs_insns PARAMS ((rtx, enum machine_mode, int,
263 rtx, int, struct hash_table *));
264 static void fixup_var_refs_1 PARAMS ((rtx, enum machine_mode, rtx *, rtx,
265 struct fixup_replacement **));
266 static rtx fixup_memory_subreg PARAMS ((rtx, rtx, int));
267 static rtx walk_fixup_memory_subreg PARAMS ((rtx, rtx, int));
268 static rtx fixup_stack_1 PARAMS ((rtx, rtx));
269 static void optimize_bit_field PARAMS ((rtx, rtx, rtx *));
270 static void instantiate_decls PARAMS ((tree, int));
271 static void instantiate_decls_1 PARAMS ((tree, int));
272 static void instantiate_decl PARAMS ((rtx, HOST_WIDE_INT, int));
273 static int instantiate_virtual_regs_1 PARAMS ((rtx *, rtx, int));
274 static void delete_handlers PARAMS ((void));
275 static void pad_to_arg_alignment PARAMS ((struct args_size *, int,
276 struct args_size *));
277 #ifndef ARGS_GROW_DOWNWARD
278 static void pad_below PARAMS ((struct args_size *, enum machine_mode,
281 static rtx round_trampoline_addr PARAMS ((rtx));
282 static tree *identify_blocks_1 PARAMS ((rtx, tree *, tree *, tree *));
283 static void reorder_blocks_1 PARAMS ((rtx, tree, varray_type *));
284 static tree blocks_nreverse PARAMS ((tree));
285 static int all_blocks PARAMS ((tree, tree *));
286 static tree *get_block_vector PARAMS ((tree, int *));
287 /* We always define `record_insns' even if its not used so that we
288 can always export `prologue_epilogue_contains'. */
289 static void record_insns PARAMS ((rtx, varray_type *)) ATTRIBUTE_UNUSED;
290 static int contains PARAMS ((rtx, varray_type));
292 static void emit_return_into_block PARAMS ((basic_block, rtx));
294 static void put_addressof_into_stack PARAMS ((rtx, struct hash_table *));
295 static boolean purge_addressof_1 PARAMS ((rtx *, rtx, int, int,
296 struct hash_table *));
298 static void keep_stack_depressed PARAMS ((rtx));
300 static int is_addressof PARAMS ((rtx *, void *));
301 static struct hash_entry *insns_for_mem_newfunc PARAMS ((struct hash_entry *,
304 static unsigned long insns_for_mem_hash PARAMS ((hash_table_key));
305 static boolean insns_for_mem_comp PARAMS ((hash_table_key, hash_table_key));
306 static int insns_for_mem_walk PARAMS ((rtx *, void *));
307 static void compute_insns_for_mem PARAMS ((rtx, rtx, struct hash_table *));
308 static void mark_temp_slot PARAMS ((struct temp_slot *));
309 static void mark_function_status PARAMS ((struct function *));
310 static void mark_function_chain PARAMS ((void *));
311 static void prepare_function_start PARAMS ((void));
312 static void do_clobber_return_reg PARAMS ((rtx, void *));
313 static void do_use_return_reg PARAMS ((rtx, void *));
315 /* Pointer to chain of `struct function' for containing functions. */
316 struct function *outer_function_chain;
318 /* Given a function decl for a containing function,
319 return the `struct function' for it. */
322 find_function_data (decl)
327 for (p = outer_function_chain; p; p = p->next)
334 /* Save the current context for compilation of a nested function.
335 This is called from language-specific code. The caller should use
336 the save_lang_status callback to save any language-specific state,
337 since this function knows only about language-independent
341 push_function_context_to (context)
344 struct function *p, *context_data;
348 context_data = (context == current_function_decl
350 : find_function_data (context));
351 context_data->contains_functions = 1;
355 init_dummy_function_start ();
358 p->next = outer_function_chain;
359 outer_function_chain = p;
360 p->fixup_var_refs_queue = 0;
362 save_tree_status (p);
363 if (save_lang_status)
364 (*save_lang_status) (p);
365 if (save_machine_status)
366 (*save_machine_status) (p);
372 push_function_context ()
374 push_function_context_to (current_function_decl);
377 /* Restore the last saved context, at the end of a nested function.
378 This function is called from language-specific code. */
381 pop_function_context_from (context)
382 tree context ATTRIBUTE_UNUSED;
384 struct function *p = outer_function_chain;
385 struct var_refs_queue *queue;
386 struct var_refs_queue *next;
389 outer_function_chain = p->next;
391 current_function_decl = p->decl;
394 restore_tree_status (p);
395 restore_emit_status (p);
397 if (restore_machine_status)
398 (*restore_machine_status) (p);
399 if (restore_lang_status)
400 (*restore_lang_status) (p);
402 /* Finish doing put_var_into_stack for any of our variables
403 which became addressable during the nested function. */
404 for (queue = p->fixup_var_refs_queue; queue; queue = next)
407 fixup_var_refs (queue->modified, queue->promoted_mode,
408 queue->unsignedp, 0);
411 p->fixup_var_refs_queue = 0;
413 /* Reset variables that have known state during rtx generation. */
414 rtx_equal_function_value_matters = 1;
415 virtuals_instantiated = 0;
419 pop_function_context ()
421 pop_function_context_from (current_function_decl);
424 /* Clear out all parts of the state in F that can safely be discarded
425 after the function has been parsed, but not compiled, to let
426 garbage collection reclaim the memory. */
429 free_after_parsing (f)
432 /* f->expr->forced_labels is used by code generation. */
433 /* f->emit->regno_reg_rtx is used by code generation. */
434 /* f->varasm is used by code generation. */
435 /* f->eh->eh_return_stub_label is used by code generation. */
437 if (free_lang_status)
438 (*free_lang_status) (f);
439 free_stmt_status (f);
442 /* Clear out all parts of the state in F that can safely be discarded
443 after the function has been compiled, to let garbage collection
444 reclaim the memory. */
447 free_after_compilation (f)
450 struct temp_slot *ts;
451 struct temp_slot *next;
454 free_expr_status (f);
455 free_emit_status (f);
456 free_varasm_status (f);
458 if (free_machine_status)
459 (*free_machine_status) (f);
461 if (f->x_parm_reg_stack_loc)
462 free (f->x_parm_reg_stack_loc);
464 for (ts = f->x_temp_slots; ts; ts = next)
469 f->x_temp_slots = NULL;
471 f->arg_offset_rtx = NULL;
472 f->return_rtx = NULL;
473 f->internal_arg_pointer = NULL;
474 f->x_nonlocal_labels = NULL;
475 f->x_nonlocal_goto_handler_slots = NULL;
476 f->x_nonlocal_goto_handler_labels = NULL;
477 f->x_nonlocal_goto_stack_level = NULL;
478 f->x_cleanup_label = NULL;
479 f->x_return_label = NULL;
480 f->x_save_expr_regs = NULL;
481 f->x_stack_slot_list = NULL;
482 f->x_rtl_expr_chain = NULL;
483 f->x_tail_recursion_label = NULL;
484 f->x_tail_recursion_reentry = NULL;
485 f->x_arg_pointer_save_area = NULL;
486 f->x_context_display = NULL;
487 f->x_trampoline_list = NULL;
488 f->x_parm_birth_insn = NULL;
489 f->x_last_parm_insn = NULL;
490 f->x_parm_reg_stack_loc = NULL;
491 f->fixup_var_refs_queue = NULL;
492 f->original_arg_vector = NULL;
493 f->original_decl_initial = NULL;
494 f->inl_last_parm_insn = NULL;
495 f->epilogue_delay_list = NULL;
498 /* Allocate fixed slots in the stack frame of the current function. */
500 /* Return size needed for stack frame based on slots so far allocated in
502 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
503 the caller may have to do that. */
506 get_func_frame_size (f)
509 #ifdef FRAME_GROWS_DOWNWARD
510 return -f->x_frame_offset;
512 return f->x_frame_offset;
516 /* Return size needed for stack frame based on slots so far allocated.
517 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
518 the caller may have to do that. */
522 return get_func_frame_size (cfun);
525 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
526 with machine mode MODE.
528 ALIGN controls the amount of alignment for the address of the slot:
529 0 means according to MODE,
530 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
531 positive specifies alignment boundary in bits.
533 We do not round to stack_boundary here.
535 FUNCTION specifies the function to allocate in. */
538 assign_stack_local_1 (mode, size, align, function)
539 enum machine_mode mode;
542 struct function *function;
544 register rtx x, addr;
545 int bigend_correction = 0;
548 /* Allocate in the memory associated with the function in whose frame
550 if (function != cfun)
551 push_obstacks (function->function_obstack,
552 function->function_maybepermanent_obstack);
559 alignment = BIGGEST_ALIGNMENT;
561 alignment = GET_MODE_ALIGNMENT (mode);
563 /* Allow the target to (possibly) increase the alignment of this
565 type = type_for_mode (mode, 0);
567 alignment = LOCAL_ALIGNMENT (type, alignment);
569 alignment /= BITS_PER_UNIT;
571 else if (align == -1)
573 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
574 size = CEIL_ROUND (size, alignment);
577 alignment = align / BITS_PER_UNIT;
579 #ifdef FRAME_GROWS_DOWNWARD
580 function->x_frame_offset -= size;
583 /* Ignore alignment we can't do with expected alignment of the boundary. */
584 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
585 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
587 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
588 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
590 /* Round frame offset to that alignment.
591 We must be careful here, since FRAME_OFFSET might be negative and
592 division with a negative dividend isn't as well defined as we might
593 like. So we instead assume that ALIGNMENT is a power of two and
594 use logical operations which are unambiguous. */
595 #ifdef FRAME_GROWS_DOWNWARD
596 function->x_frame_offset = FLOOR_ROUND (function->x_frame_offset, alignment);
598 function->x_frame_offset = CEIL_ROUND (function->x_frame_offset, alignment);
601 /* On a big-endian machine, if we are allocating more space than we will use,
602 use the least significant bytes of those that are allocated. */
603 if (BYTES_BIG_ENDIAN && mode != BLKmode)
604 bigend_correction = size - GET_MODE_SIZE (mode);
606 /* If we have already instantiated virtual registers, return the actual
607 address relative to the frame pointer. */
608 if (function == cfun && virtuals_instantiated)
609 addr = plus_constant (frame_pointer_rtx,
610 (frame_offset + bigend_correction
611 + STARTING_FRAME_OFFSET));
613 addr = plus_constant (virtual_stack_vars_rtx,
614 function->x_frame_offset + bigend_correction);
616 #ifndef FRAME_GROWS_DOWNWARD
617 function->x_frame_offset += size;
620 x = gen_rtx_MEM (mode, addr);
622 function->x_stack_slot_list
623 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
625 if (function != cfun)
631 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
635 assign_stack_local (mode, size, align)
636 enum machine_mode mode;
640 return assign_stack_local_1 (mode, size, align, cfun);
643 /* Allocate a temporary stack slot and record it for possible later
646 MODE is the machine mode to be given to the returned rtx.
648 SIZE is the size in units of the space required. We do no rounding here
649 since assign_stack_local will do any required rounding.
651 KEEP is 1 if this slot is to be retained after a call to
652 free_temp_slots. Automatic variables for a block are allocated
653 with this flag. KEEP is 2 if we allocate a longer term temporary,
654 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
655 if we are to allocate something at an inner level to be treated as
656 a variable in the block (e.g., a SAVE_EXPR).
658 TYPE is the type that will be used for the stack slot. */
661 assign_stack_temp_for_type (mode, size, keep, type)
662 enum machine_mode mode;
668 HOST_WIDE_INT alias_set;
669 struct temp_slot *p, *best_p = 0;
671 /* If SIZE is -1 it means that somebody tried to allocate a temporary
672 of a variable size. */
676 /* If we know the alias set for the memory that will be used, use
677 it. If there's no TYPE, then we don't know anything about the
678 alias set for the memory. */
680 alias_set = get_alias_set (type);
685 align = BIGGEST_ALIGNMENT;
687 align = GET_MODE_ALIGNMENT (mode);
690 type = type_for_mode (mode, 0);
693 align = LOCAL_ALIGNMENT (type, align);
695 /* Try to find an available, already-allocated temporary of the proper
696 mode which meets the size and alignment requirements. Choose the
697 smallest one with the closest alignment. */
698 for (p = temp_slots; p; p = p->next)
699 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
701 && (! flag_strict_aliasing
702 || (alias_set && p->alias_set == alias_set))
703 && (best_p == 0 || best_p->size > p->size
704 || (best_p->size == p->size && best_p->align > p->align)))
706 if (p->align == align && p->size == size)
714 /* Make our best, if any, the one to use. */
717 /* If there are enough aligned bytes left over, make them into a new
718 temp_slot so that the extra bytes don't get wasted. Do this only
719 for BLKmode slots, so that we can be sure of the alignment. */
720 if (GET_MODE (best_p->slot) == BLKmode)
722 int alignment = best_p->align / BITS_PER_UNIT;
723 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
725 if (best_p->size - rounded_size >= alignment)
727 p = (struct temp_slot *) xmalloc (sizeof (struct temp_slot));
728 p->in_use = p->addr_taken = 0;
729 p->size = best_p->size - rounded_size;
730 p->base_offset = best_p->base_offset + rounded_size;
731 p->full_size = best_p->full_size - rounded_size;
732 p->slot = gen_rtx_MEM (BLKmode,
733 plus_constant (XEXP (best_p->slot, 0),
735 p->align = best_p->align;
738 p->alias_set = best_p->alias_set;
739 p->next = temp_slots;
742 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
745 best_p->size = rounded_size;
746 best_p->full_size = rounded_size;
753 /* If we still didn't find one, make a new temporary. */
756 HOST_WIDE_INT frame_offset_old = frame_offset;
758 p = (struct temp_slot *) xmalloc (sizeof (struct temp_slot));
760 /* We are passing an explicit alignment request to assign_stack_local.
761 One side effect of that is assign_stack_local will not round SIZE
762 to ensure the frame offset remains suitably aligned.
764 So for requests which depended on the rounding of SIZE, we go ahead
765 and round it now. We also make sure ALIGNMENT is at least
766 BIGGEST_ALIGNMENT. */
767 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
769 p->slot = assign_stack_local (mode,
771 ? CEIL_ROUND (size, align / BITS_PER_UNIT)
776 p->alias_set = alias_set;
778 /* The following slot size computation is necessary because we don't
779 know the actual size of the temporary slot until assign_stack_local
780 has performed all the frame alignment and size rounding for the
781 requested temporary. Note that extra space added for alignment
782 can be either above or below this stack slot depending on which
783 way the frame grows. We include the extra space if and only if it
784 is above this slot. */
785 #ifdef FRAME_GROWS_DOWNWARD
786 p->size = frame_offset_old - frame_offset;
791 /* Now define the fields used by combine_temp_slots. */
792 #ifdef FRAME_GROWS_DOWNWARD
793 p->base_offset = frame_offset;
794 p->full_size = frame_offset_old - frame_offset;
796 p->base_offset = frame_offset_old;
797 p->full_size = frame_offset - frame_offset_old;
800 p->next = temp_slots;
806 p->rtl_expr = seq_rtl_expr;
810 p->level = target_temp_slot_level;
815 p->level = var_temp_slot_level;
820 p->level = temp_slot_level;
824 /* We may be reusing an old slot, so clear any MEM flags that may have been
826 RTX_UNCHANGING_P (p->slot) = 0;
827 MEM_IN_STRUCT_P (p->slot) = 0;
828 MEM_SCALAR_P (p->slot) = 0;
829 MEM_ALIAS_SET (p->slot) = alias_set;
832 MEM_SET_IN_STRUCT_P (p->slot, AGGREGATE_TYPE_P (type));
837 /* Allocate a temporary stack slot and record it for possible later
838 reuse. First three arguments are same as in preceding function. */
841 assign_stack_temp (mode, size, keep)
842 enum machine_mode mode;
846 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
849 /* Assign a temporary of given TYPE.
850 KEEP is as for assign_stack_temp.
851 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
852 it is 0 if a register is OK.
853 DONT_PROMOTE is 1 if we should not promote values in register
857 assign_temp (type, keep, memory_required, dont_promote)
861 int dont_promote ATTRIBUTE_UNUSED;
863 enum machine_mode mode = TYPE_MODE (type);
864 #ifndef PROMOTE_FOR_CALL_ONLY
865 int unsignedp = TREE_UNSIGNED (type);
868 if (mode == BLKmode || memory_required)
870 HOST_WIDE_INT size = int_size_in_bytes (type);
873 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
874 problems with allocating the stack space. */
878 /* Unfortunately, we don't yet know how to allocate variable-sized
879 temporaries. However, sometimes we have a fixed upper limit on
880 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
881 instead. This is the case for Chill variable-sized strings. */
882 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
883 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
884 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
885 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
887 tmp = assign_stack_temp_for_type (mode, size, keep, type);
891 #ifndef PROMOTE_FOR_CALL_ONLY
893 mode = promote_mode (type, mode, &unsignedp, 0);
896 return gen_reg_rtx (mode);
899 /* Combine temporary stack slots which are adjacent on the stack.
901 This allows for better use of already allocated stack space. This is only
902 done for BLKmode slots because we can be sure that we won't have alignment
903 problems in this case. */
906 combine_temp_slots ()
908 struct temp_slot *p, *q;
909 struct temp_slot *prev_p, *prev_q;
912 /* We can't combine slots, because the information about which slot
913 is in which alias set will be lost. */
914 if (flag_strict_aliasing)
917 /* If there are a lot of temp slots, don't do anything unless
918 high levels of optimizaton. */
919 if (! flag_expensive_optimizations)
920 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
921 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
924 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
928 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
929 for (q = p->next, prev_q = p; q; q = prev_q->next)
932 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
934 if (p->base_offset + p->full_size == q->base_offset)
936 /* Q comes after P; combine Q into P. */
938 p->full_size += q->full_size;
941 else if (q->base_offset + q->full_size == p->base_offset)
943 /* P comes after Q; combine P into Q. */
945 q->full_size += p->full_size;
950 /* Either delete Q or advance past it. */
953 prev_q->next = q->next;
959 /* Either delete P or advance past it. */
963 prev_p->next = p->next;
965 temp_slots = p->next;
972 /* Find the temp slot corresponding to the object at address X. */
974 static struct temp_slot *
975 find_temp_slot_from_address (x)
981 for (p = temp_slots; p; p = p->next)
986 else if (XEXP (p->slot, 0) == x
988 || (GET_CODE (x) == PLUS
989 && XEXP (x, 0) == virtual_stack_vars_rtx
990 && GET_CODE (XEXP (x, 1)) == CONST_INT
991 && INTVAL (XEXP (x, 1)) >= p->base_offset
992 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
995 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
996 for (next = p->address; next; next = XEXP (next, 1))
997 if (XEXP (next, 0) == x)
1001 /* If we have a sum involving a register, see if it points to a temp
1003 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == REG
1004 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
1006 else if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == REG
1007 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
1013 /* Indicate that NEW is an alternate way of referring to the temp slot
1014 that previously was known by OLD. */
1017 update_temp_slot_address (old, new)
1020 struct temp_slot *p;
1022 if (rtx_equal_p (old, new))
1025 p = find_temp_slot_from_address (old);
1027 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
1028 is a register, see if one operand of the PLUS is a temporary
1029 location. If so, NEW points into it. Otherwise, if both OLD and
1030 NEW are a PLUS and if there is a register in common between them.
1031 If so, try a recursive call on those values. */
1034 if (GET_CODE (old) != PLUS)
1037 if (GET_CODE (new) == REG)
1039 update_temp_slot_address (XEXP (old, 0), new);
1040 update_temp_slot_address (XEXP (old, 1), new);
1043 else if (GET_CODE (new) != PLUS)
1046 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
1047 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
1048 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
1049 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
1050 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
1051 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
1052 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
1053 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
1058 /* Otherwise add an alias for the temp's address. */
1059 else if (p->address == 0)
1063 if (GET_CODE (p->address) != EXPR_LIST)
1064 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1066 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1070 /* If X could be a reference to a temporary slot, mark the fact that its
1071 address was taken. */
1074 mark_temp_addr_taken (x)
1077 struct temp_slot *p;
1082 /* If X is not in memory or is at a constant address, it cannot be in
1083 a temporary slot. */
1084 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1087 p = find_temp_slot_from_address (XEXP (x, 0));
1092 /* If X could be a reference to a temporary slot, mark that slot as
1093 belonging to the to one level higher than the current level. If X
1094 matched one of our slots, just mark that one. Otherwise, we can't
1095 easily predict which it is, so upgrade all of them. Kept slots
1096 need not be touched.
1098 This is called when an ({...}) construct occurs and a statement
1099 returns a value in memory. */
1102 preserve_temp_slots (x)
1105 struct temp_slot *p = 0;
1107 /* If there is no result, we still might have some objects whose address
1108 were taken, so we need to make sure they stay around. */
1111 for (p = temp_slots; p; p = p->next)
1112 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1118 /* If X is a register that is being used as a pointer, see if we have
1119 a temporary slot we know it points to. To be consistent with
1120 the code below, we really should preserve all non-kept slots
1121 if we can't find a match, but that seems to be much too costly. */
1122 if (GET_CODE (x) == REG && REGNO_POINTER_FLAG (REGNO (x)))
1123 p = find_temp_slot_from_address (x);
1125 /* If X is not in memory or is at a constant address, it cannot be in
1126 a temporary slot, but it can contain something whose address was
1128 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1130 for (p = temp_slots; p; p = p->next)
1131 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1137 /* First see if we can find a match. */
1139 p = find_temp_slot_from_address (XEXP (x, 0));
1143 /* Move everything at our level whose address was taken to our new
1144 level in case we used its address. */
1145 struct temp_slot *q;
1147 if (p->level == temp_slot_level)
1149 for (q = temp_slots; q; q = q->next)
1150 if (q != p && q->addr_taken && q->level == p->level)
1159 /* Otherwise, preserve all non-kept slots at this level. */
1160 for (p = temp_slots; p; p = p->next)
1161 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1165 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1166 with that RTL_EXPR, promote it into a temporary slot at the present
1167 level so it will not be freed when we free slots made in the
1171 preserve_rtl_expr_result (x)
1174 struct temp_slot *p;
1176 /* If X is not in memory or is at a constant address, it cannot be in
1177 a temporary slot. */
1178 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1181 /* If we can find a match, move it to our level unless it is already at
1183 p = find_temp_slot_from_address (XEXP (x, 0));
1186 p->level = MIN (p->level, temp_slot_level);
1193 /* Free all temporaries used so far. This is normally called at the end
1194 of generating code for a statement. Don't free any temporaries
1195 currently in use for an RTL_EXPR that hasn't yet been emitted.
1196 We could eventually do better than this since it can be reused while
1197 generating the same RTL_EXPR, but this is complex and probably not
1203 struct temp_slot *p;
1205 for (p = temp_slots; p; p = p->next)
1206 if (p->in_use && p->level == temp_slot_level && ! p->keep
1207 && p->rtl_expr == 0)
1210 combine_temp_slots ();
1213 /* Free all temporary slots used in T, an RTL_EXPR node. */
1216 free_temps_for_rtl_expr (t)
1219 struct temp_slot *p;
1221 for (p = temp_slots; p; p = p->next)
1222 if (p->rtl_expr == t)
1224 /* If this slot is below the current TEMP_SLOT_LEVEL, then it
1225 needs to be preserved. This can happen if a temporary in
1226 the RTL_EXPR was addressed; preserve_temp_slots will move
1227 the temporary into a higher level. */
1228 if (temp_slot_level <= p->level)
1231 p->rtl_expr = NULL_TREE;
1234 combine_temp_slots ();
1237 /* Mark all temporaries ever allocated in this function as not suitable
1238 for reuse until the current level is exited. */
1241 mark_all_temps_used ()
1243 struct temp_slot *p;
1245 for (p = temp_slots; p; p = p->next)
1247 p->in_use = p->keep = 1;
1248 p->level = MIN (p->level, temp_slot_level);
1252 /* Push deeper into the nesting level for stack temporaries. */
1260 /* Likewise, but save the new level as the place to allocate variables
1265 push_temp_slots_for_block ()
1269 var_temp_slot_level = temp_slot_level;
1272 /* Likewise, but save the new level as the place to allocate temporaries
1273 for TARGET_EXPRs. */
1276 push_temp_slots_for_target ()
1280 target_temp_slot_level = temp_slot_level;
1283 /* Set and get the value of target_temp_slot_level. The only
1284 permitted use of these functions is to save and restore this value. */
1287 get_target_temp_slot_level ()
1289 return target_temp_slot_level;
1293 set_target_temp_slot_level (level)
1296 target_temp_slot_level = level;
1300 /* Pop a temporary nesting level. All slots in use in the current level
1306 struct temp_slot *p;
1308 for (p = temp_slots; p; p = p->next)
1309 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1312 combine_temp_slots ();
1317 /* Initialize temporary slots. */
1322 /* We have not allocated any temporaries yet. */
1324 temp_slot_level = 0;
1325 var_temp_slot_level = 0;
1326 target_temp_slot_level = 0;
1329 /* Retroactively move an auto variable from a register to a stack slot.
1330 This is done when an address-reference to the variable is seen. */
1333 put_var_into_stack (decl)
1337 enum machine_mode promoted_mode, decl_mode;
1338 struct function *function = 0;
1340 int can_use_addressof;
1341 int volatilep = TREE_CODE (decl) != SAVE_EXPR && TREE_THIS_VOLATILE (decl);
1342 int usedp = (TREE_USED (decl)
1343 || (TREE_CODE (decl) != SAVE_EXPR && DECL_INITIAL (decl) != 0));
1345 context = decl_function_context (decl);
1347 /* Get the current rtl used for this object and its original mode. */
1348 reg = TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl) : DECL_RTL (decl);
1350 /* No need to do anything if decl has no rtx yet
1351 since in that case caller is setting TREE_ADDRESSABLE
1352 and a stack slot will be assigned when the rtl is made. */
1356 /* Get the declared mode for this object. */
1357 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1358 : DECL_MODE (decl));
1359 /* Get the mode it's actually stored in. */
1360 promoted_mode = GET_MODE (reg);
1362 /* If this variable comes from an outer function,
1363 find that function's saved context. */
1364 if (context != current_function_decl && context != inline_function_decl)
1365 for (function = outer_function_chain; function; function = function->next)
1366 if (function->decl == context)
1369 /* If this is a variable-size object with a pseudo to address it,
1370 put that pseudo into the stack, if the var is nonlocal. */
1371 if (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl)
1372 && GET_CODE (reg) == MEM
1373 && GET_CODE (XEXP (reg, 0)) == REG
1374 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1376 reg = XEXP (reg, 0);
1377 decl_mode = promoted_mode = GET_MODE (reg);
1383 /* FIXME make it work for promoted modes too */
1384 && decl_mode == promoted_mode
1385 #ifdef NON_SAVING_SETJMP
1386 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1390 /* If we can't use ADDRESSOF, make sure we see through one we already
1392 if (! can_use_addressof && GET_CODE (reg) == MEM
1393 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1394 reg = XEXP (XEXP (reg, 0), 0);
1396 /* Now we should have a value that resides in one or more pseudo regs. */
1398 if (GET_CODE (reg) == REG)
1400 /* If this variable lives in the current function and we don't need
1401 to put things in the stack for the sake of setjmp, try to keep it
1402 in a register until we know we actually need the address. */
1403 if (can_use_addressof)
1404 gen_mem_addressof (reg, decl);
1406 put_reg_into_stack (function, reg, TREE_TYPE (decl), promoted_mode,
1407 decl_mode, volatilep, 0, usedp, 0);
1409 else if (GET_CODE (reg) == CONCAT)
1411 /* A CONCAT contains two pseudos; put them both in the stack.
1412 We do it so they end up consecutive.
1413 We fixup references to the parts only after we fixup references
1414 to the whole CONCAT, lest we do double fixups for the latter
1416 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1417 tree part_type = type_for_mode (part_mode, 0);
1418 rtx lopart = XEXP (reg, 0);
1419 rtx hipart = XEXP (reg, 1);
1420 #ifdef FRAME_GROWS_DOWNWARD
1421 /* Since part 0 should have a lower address, do it second. */
1422 put_reg_into_stack (function, hipart, part_type, part_mode,
1423 part_mode, volatilep, 0, 0, 0);
1424 put_reg_into_stack (function, lopart, part_type, part_mode,
1425 part_mode, volatilep, 0, 0, 0);
1427 put_reg_into_stack (function, lopart, part_type, part_mode,
1428 part_mode, volatilep, 0, 0, 0);
1429 put_reg_into_stack (function, hipart, part_type, part_mode,
1430 part_mode, volatilep, 0, 0, 0);
1433 /* Change the CONCAT into a combined MEM for both parts. */
1434 PUT_CODE (reg, MEM);
1435 set_mem_attributes (reg, decl, 1);
1437 /* The two parts are in memory order already.
1438 Use the lower parts address as ours. */
1439 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1440 /* Prevent sharing of rtl that might lose. */
1441 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1442 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1445 schedule_fixup_var_refs (function, reg, TREE_TYPE (decl),
1447 schedule_fixup_var_refs (function, lopart, part_type, part_mode, 0);
1448 schedule_fixup_var_refs (function, hipart, part_type, part_mode, 0);
1454 if (current_function_check_memory_usage)
1455 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
1456 XEXP (reg, 0), Pmode,
1457 GEN_INT (GET_MODE_SIZE (GET_MODE (reg))),
1458 TYPE_MODE (sizetype),
1459 GEN_INT (MEMORY_USE_RW),
1460 TYPE_MODE (integer_type_node));
1463 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1464 into the stack frame of FUNCTION (0 means the current function).
1465 DECL_MODE is the machine mode of the user-level data type.
1466 PROMOTED_MODE is the machine mode of the register.
1467 VOLATILE_P is nonzero if this is for a "volatile" decl.
1468 USED_P is nonzero if this reg might have already been used in an insn. */
1471 put_reg_into_stack (function, reg, type, promoted_mode, decl_mode, volatile_p,
1472 original_regno, used_p, ht)
1473 struct function *function;
1476 enum machine_mode promoted_mode, decl_mode;
1478 unsigned int original_regno;
1480 struct hash_table *ht;
1482 struct function *func = function ? function : cfun;
1484 unsigned int regno = original_regno;
1487 regno = REGNO (reg);
1489 if (regno < func->x_max_parm_reg)
1490 new = func->x_parm_reg_stack_loc[regno];
1493 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode), 0, func);
1495 PUT_CODE (reg, MEM);
1496 PUT_MODE (reg, decl_mode);
1497 XEXP (reg, 0) = XEXP (new, 0);
1498 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1499 MEM_VOLATILE_P (reg) = volatile_p;
1501 /* If this is a memory ref that contains aggregate components,
1502 mark it as such for cse and loop optimize. If we are reusing a
1503 previously generated stack slot, then we need to copy the bit in
1504 case it was set for other reasons. For instance, it is set for
1505 __builtin_va_alist. */
1508 MEM_SET_IN_STRUCT_P (reg,
1509 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1510 MEM_ALIAS_SET (reg) = get_alias_set (type);
1513 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht);
1516 /* Make sure that all refs to the variable, previously made
1517 when it was a register, are fixed up to be valid again.
1518 See function above for meaning of arguments. */
1520 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht)
1521 struct function *function;
1524 enum machine_mode promoted_mode;
1525 struct hash_table *ht;
1527 int unsigned_p = type ? TREE_UNSIGNED (type) : 0;
1531 struct var_refs_queue *temp;
1534 = (struct var_refs_queue *) xmalloc (sizeof (struct var_refs_queue));
1535 temp->modified = reg;
1536 temp->promoted_mode = promoted_mode;
1537 temp->unsignedp = unsigned_p;
1538 temp->next = function->fixup_var_refs_queue;
1539 function->fixup_var_refs_queue = temp;
1542 /* Variable is local; fix it up now. */
1543 fixup_var_refs (reg, promoted_mode, unsigned_p, ht);
1547 fixup_var_refs (var, promoted_mode, unsignedp, ht)
1549 enum machine_mode promoted_mode;
1551 struct hash_table *ht;
1554 rtx first_insn = get_insns ();
1555 struct sequence_stack *stack = seq_stack;
1556 tree rtl_exps = rtl_expr_chain;
1559 /* Must scan all insns for stack-refs that exceed the limit. */
1560 fixup_var_refs_insns (var, promoted_mode, unsignedp, first_insn,
1562 /* If there's a hash table, it must record all uses of VAR. */
1566 /* Scan all pending sequences too. */
1567 for (; stack; stack = stack->next)
1569 push_to_sequence (stack->first);
1570 fixup_var_refs_insns (var, promoted_mode, unsignedp,
1571 stack->first, stack->next != 0, 0);
1572 /* Update remembered end of sequence
1573 in case we added an insn at the end. */
1574 stack->last = get_last_insn ();
1578 /* Scan all waiting RTL_EXPRs too. */
1579 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1581 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1582 if (seq != const0_rtx && seq != 0)
1584 push_to_sequence (seq);
1585 fixup_var_refs_insns (var, promoted_mode, unsignedp, seq, 0, 0);
1590 /* Scan the catch clauses for exception handling too. */
1591 push_to_full_sequence (catch_clauses, catch_clauses_last);
1592 fixup_var_refs_insns (var, promoted_mode, unsignedp, catch_clauses, 0, 0);
1593 end_full_sequence (&catch_clauses, &catch_clauses_last);
1595 /* Scan sequences saved in CALL_PLACEHOLDERS too. */
1596 for (insn = first_insn; insn; insn = NEXT_INSN (insn))
1598 if (GET_CODE (insn) == CALL_INSN
1599 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
1603 /* Look at the Normal call, sibling call and tail recursion
1604 sequences attached to the CALL_PLACEHOLDER. */
1605 for (i = 0; i < 3; i++)
1607 rtx seq = XEXP (PATTERN (insn), i);
1610 push_to_sequence (seq);
1611 fixup_var_refs_insns (var, promoted_mode, unsignedp,
1613 XEXP (PATTERN (insn), i) = get_insns ();
1621 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1622 some part of an insn. Return a struct fixup_replacement whose OLD
1623 value is equal to X. Allocate a new structure if no such entry exists. */
1625 static struct fixup_replacement *
1626 find_fixup_replacement (replacements, x)
1627 struct fixup_replacement **replacements;
1630 struct fixup_replacement *p;
1632 /* See if we have already replaced this. */
1633 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1638 p = (struct fixup_replacement *) oballoc (sizeof (struct fixup_replacement));
1641 p->next = *replacements;
1648 /* Scan the insn-chain starting with INSN for refs to VAR
1649 and fix them up. TOPLEVEL is nonzero if this chain is the
1650 main chain of insns for the current function. */
1653 fixup_var_refs_insns (var, promoted_mode, unsignedp, insn, toplevel, ht)
1655 enum machine_mode promoted_mode;
1659 struct hash_table *ht;
1662 rtx insn_list = NULL_RTX;
1664 /* If we already know which INSNs reference VAR there's no need
1665 to walk the entire instruction chain. */
1668 insn_list = ((struct insns_for_mem_entry *)
1669 hash_lookup (ht, var, /*create=*/0, /*copy=*/0))->insns;
1670 insn = insn_list ? XEXP (insn_list, 0) : NULL_RTX;
1671 insn_list = XEXP (insn_list, 1);
1676 rtx next = NEXT_INSN (insn);
1677 rtx set, prev, prev_set;
1682 /* Remember the notes in case we delete the insn. */
1683 note = REG_NOTES (insn);
1685 /* If this is a CLOBBER of VAR, delete it.
1687 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1688 and REG_RETVAL notes too. */
1689 if (GET_CODE (PATTERN (insn)) == CLOBBER
1690 && (XEXP (PATTERN (insn), 0) == var
1691 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1692 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1693 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1695 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1696 /* The REG_LIBCALL note will go away since we are going to
1697 turn INSN into a NOTE, so just delete the
1698 corresponding REG_RETVAL note. */
1699 remove_note (XEXP (note, 0),
1700 find_reg_note (XEXP (note, 0), REG_RETVAL,
1703 /* In unoptimized compilation, we shouldn't call delete_insn
1704 except in jump.c doing warnings. */
1705 PUT_CODE (insn, NOTE);
1706 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1707 NOTE_SOURCE_FILE (insn) = 0;
1710 /* The insn to load VAR from a home in the arglist
1711 is now a no-op. When we see it, just delete it.
1712 Similarly if this is storing VAR from a register from which
1713 it was loaded in the previous insn. This will occur
1714 when an ADDRESSOF was made for an arglist slot. */
1716 && (set = single_set (insn)) != 0
1717 && SET_DEST (set) == var
1718 /* If this represents the result of an insn group,
1719 don't delete the insn. */
1720 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1721 && (rtx_equal_p (SET_SRC (set), var)
1722 || (GET_CODE (SET_SRC (set)) == REG
1723 && (prev = prev_nonnote_insn (insn)) != 0
1724 && (prev_set = single_set (prev)) != 0
1725 && SET_DEST (prev_set) == SET_SRC (set)
1726 && rtx_equal_p (SET_SRC (prev_set), var))))
1728 /* In unoptimized compilation, we shouldn't call delete_insn
1729 except in jump.c doing warnings. */
1730 PUT_CODE (insn, NOTE);
1731 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1732 NOTE_SOURCE_FILE (insn) = 0;
1733 if (insn == last_parm_insn)
1734 last_parm_insn = PREV_INSN (next);
1738 struct fixup_replacement *replacements = 0;
1739 rtx next_insn = NEXT_INSN (insn);
1741 if (SMALL_REGISTER_CLASSES)
1743 /* If the insn that copies the results of a CALL_INSN
1744 into a pseudo now references VAR, we have to use an
1745 intermediate pseudo since we want the life of the
1746 return value register to be only a single insn.
1748 If we don't use an intermediate pseudo, such things as
1749 address computations to make the address of VAR valid
1750 if it is not can be placed between the CALL_INSN and INSN.
1752 To make sure this doesn't happen, we record the destination
1753 of the CALL_INSN and see if the next insn uses both that
1756 if (call_dest != 0 && GET_CODE (insn) == INSN
1757 && reg_mentioned_p (var, PATTERN (insn))
1758 && reg_mentioned_p (call_dest, PATTERN (insn)))
1760 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1762 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1764 PATTERN (insn) = replace_rtx (PATTERN (insn),
1768 if (GET_CODE (insn) == CALL_INSN
1769 && GET_CODE (PATTERN (insn)) == SET)
1770 call_dest = SET_DEST (PATTERN (insn));
1771 else if (GET_CODE (insn) == CALL_INSN
1772 && GET_CODE (PATTERN (insn)) == PARALLEL
1773 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1774 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1779 /* See if we have to do anything to INSN now that VAR is in
1780 memory. If it needs to be loaded into a pseudo, use a single
1781 pseudo for the entire insn in case there is a MATCH_DUP
1782 between two operands. We pass a pointer to the head of
1783 a list of struct fixup_replacements. If fixup_var_refs_1
1784 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1785 it will record them in this list.
1787 If it allocated a pseudo for any replacement, we copy into
1790 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1793 /* If this is last_parm_insn, and any instructions were output
1794 after it to fix it up, then we must set last_parm_insn to
1795 the last such instruction emitted. */
1796 if (insn == last_parm_insn)
1797 last_parm_insn = PREV_INSN (next_insn);
1799 while (replacements)
1801 if (GET_CODE (replacements->new) == REG)
1806 /* OLD might be a (subreg (mem)). */
1807 if (GET_CODE (replacements->old) == SUBREG)
1809 = fixup_memory_subreg (replacements->old, insn, 0);
1812 = fixup_stack_1 (replacements->old, insn);
1814 insert_before = insn;
1816 /* If we are changing the mode, do a conversion.
1817 This might be wasteful, but combine.c will
1818 eliminate much of the waste. */
1820 if (GET_MODE (replacements->new)
1821 != GET_MODE (replacements->old))
1824 convert_move (replacements->new,
1825 replacements->old, unsignedp);
1826 seq = gen_sequence ();
1830 seq = gen_move_insn (replacements->new,
1833 emit_insn_before (seq, insert_before);
1836 replacements = replacements->next;
1840 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1841 But don't touch other insns referred to by reg-notes;
1842 we will get them elsewhere. */
1845 if (GET_CODE (note) != INSN_LIST)
1847 = walk_fixup_memory_subreg (XEXP (note, 0), insn, 1);
1848 note = XEXP (note, 1);
1856 insn = XEXP (insn_list, 0);
1857 insn_list = XEXP (insn_list, 1);
1864 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1865 See if the rtx expression at *LOC in INSN needs to be changed.
1867 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1868 contain a list of original rtx's and replacements. If we find that we need
1869 to modify this insn by replacing a memory reference with a pseudo or by
1870 making a new MEM to implement a SUBREG, we consult that list to see if
1871 we have already chosen a replacement. If none has already been allocated,
1872 we allocate it and update the list. fixup_var_refs_insns will copy VAR
1873 or the SUBREG, as appropriate, to the pseudo. */
1876 fixup_var_refs_1 (var, promoted_mode, loc, insn, replacements)
1878 enum machine_mode promoted_mode;
1881 struct fixup_replacement **replacements;
1884 register rtx x = *loc;
1885 RTX_CODE code = GET_CODE (x);
1886 register const char *fmt;
1887 register rtx tem, tem1;
1888 struct fixup_replacement *replacement;
1893 if (XEXP (x, 0) == var)
1895 /* Prevent sharing of rtl that might lose. */
1896 rtx sub = copy_rtx (XEXP (var, 0));
1898 if (! validate_change (insn, loc, sub, 0))
1900 rtx y = gen_reg_rtx (GET_MODE (sub));
1903 /* We should be able to replace with a register or all is lost.
1904 Note that we can't use validate_change to verify this, since
1905 we're not caring for replacing all dups simultaneously. */
1906 if (! validate_replace_rtx (*loc, y, insn))
1909 /* Careful! First try to recognize a direct move of the
1910 value, mimicking how things are done in gen_reload wrt
1911 PLUS. Consider what happens when insn is a conditional
1912 move instruction and addsi3 clobbers flags. */
1915 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1916 seq = gen_sequence ();
1919 if (recog_memoized (new_insn) < 0)
1921 /* That failed. Fall back on force_operand and hope. */
1924 force_operand (sub, y);
1925 seq = gen_sequence ();
1930 /* Don't separate setter from user. */
1931 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1932 insn = PREV_INSN (insn);
1935 emit_insn_before (seq, insn);
1943 /* If we already have a replacement, use it. Otherwise,
1944 try to fix up this address in case it is invalid. */
1946 replacement = find_fixup_replacement (replacements, var);
1947 if (replacement->new)
1949 *loc = replacement->new;
1953 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1955 /* Unless we are forcing memory to register or we changed the mode,
1956 we can leave things the way they are if the insn is valid. */
1958 INSN_CODE (insn) = -1;
1959 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1960 && recog_memoized (insn) >= 0)
1963 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1967 /* If X contains VAR, we need to unshare it here so that we update
1968 each occurrence separately. But all identical MEMs in one insn
1969 must be replaced with the same rtx because of the possibility of
1972 if (reg_mentioned_p (var, x))
1974 replacement = find_fixup_replacement (replacements, x);
1975 if (replacement->new == 0)
1976 replacement->new = copy_most_rtx (x, var);
1978 *loc = x = replacement->new;
1979 code = GET_CODE (x);
1995 /* Note that in some cases those types of expressions are altered
1996 by optimize_bit_field, and do not survive to get here. */
1997 if (XEXP (x, 0) == var
1998 || (GET_CODE (XEXP (x, 0)) == SUBREG
1999 && SUBREG_REG (XEXP (x, 0)) == var))
2001 /* Get TEM as a valid MEM in the mode presently in the insn.
2003 We don't worry about the possibility of MATCH_DUP here; it
2004 is highly unlikely and would be tricky to handle. */
2007 if (GET_CODE (tem) == SUBREG)
2009 if (GET_MODE_BITSIZE (GET_MODE (tem))
2010 > GET_MODE_BITSIZE (GET_MODE (var)))
2012 replacement = find_fixup_replacement (replacements, var);
2013 if (replacement->new == 0)
2014 replacement->new = gen_reg_rtx (GET_MODE (var));
2015 SUBREG_REG (tem) = replacement->new;
2018 tem = fixup_memory_subreg (tem, insn, 0);
2021 tem = fixup_stack_1 (tem, insn);
2023 /* Unless we want to load from memory, get TEM into the proper mode
2024 for an extract from memory. This can only be done if the
2025 extract is at a constant position and length. */
2027 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
2028 && GET_CODE (XEXP (x, 2)) == CONST_INT
2029 && ! mode_dependent_address_p (XEXP (tem, 0))
2030 && ! MEM_VOLATILE_P (tem))
2032 enum machine_mode wanted_mode = VOIDmode;
2033 enum machine_mode is_mode = GET_MODE (tem);
2034 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
2037 if (GET_CODE (x) == ZERO_EXTRACT)
2040 = insn_data[(int) CODE_FOR_extzv].operand[1].mode;
2041 if (wanted_mode == VOIDmode)
2042 wanted_mode = word_mode;
2046 if (GET_CODE (x) == SIGN_EXTRACT)
2048 wanted_mode = insn_data[(int) CODE_FOR_extv].operand[1].mode;
2049 if (wanted_mode == VOIDmode)
2050 wanted_mode = word_mode;
2053 /* If we have a narrower mode, we can do something. */
2054 if (wanted_mode != VOIDmode
2055 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2057 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2058 rtx old_pos = XEXP (x, 2);
2061 /* If the bytes and bits are counted differently, we
2062 must adjust the offset. */
2063 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2064 offset = (GET_MODE_SIZE (is_mode)
2065 - GET_MODE_SIZE (wanted_mode) - offset);
2067 pos %= GET_MODE_BITSIZE (wanted_mode);
2069 newmem = gen_rtx_MEM (wanted_mode,
2070 plus_constant (XEXP (tem, 0), offset));
2071 MEM_COPY_ATTRIBUTES (newmem, tem);
2073 /* Make the change and see if the insn remains valid. */
2074 INSN_CODE (insn) = -1;
2075 XEXP (x, 0) = newmem;
2076 XEXP (x, 2) = GEN_INT (pos);
2078 if (recog_memoized (insn) >= 0)
2081 /* Otherwise, restore old position. XEXP (x, 0) will be
2083 XEXP (x, 2) = old_pos;
2087 /* If we get here, the bitfield extract insn can't accept a memory
2088 reference. Copy the input into a register. */
2090 tem1 = gen_reg_rtx (GET_MODE (tem));
2091 emit_insn_before (gen_move_insn (tem1, tem), insn);
2098 if (SUBREG_REG (x) == var)
2100 /* If this is a special SUBREG made because VAR was promoted
2101 from a wider mode, replace it with VAR and call ourself
2102 recursively, this time saying that the object previously
2103 had its current mode (by virtue of the SUBREG). */
2105 if (SUBREG_PROMOTED_VAR_P (x))
2108 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements);
2112 /* If this SUBREG makes VAR wider, it has become a paradoxical
2113 SUBREG with VAR in memory, but these aren't allowed at this
2114 stage of the compilation. So load VAR into a pseudo and take
2115 a SUBREG of that pseudo. */
2116 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2118 replacement = find_fixup_replacement (replacements, var);
2119 if (replacement->new == 0)
2120 replacement->new = gen_reg_rtx (GET_MODE (var));
2121 SUBREG_REG (x) = replacement->new;
2125 /* See if we have already found a replacement for this SUBREG.
2126 If so, use it. Otherwise, make a MEM and see if the insn
2127 is recognized. If not, or if we should force MEM into a register,
2128 make a pseudo for this SUBREG. */
2129 replacement = find_fixup_replacement (replacements, x);
2130 if (replacement->new)
2132 *loc = replacement->new;
2136 replacement->new = *loc = fixup_memory_subreg (x, insn, 0);
2138 INSN_CODE (insn) = -1;
2139 if (! flag_force_mem && recog_memoized (insn) >= 0)
2142 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2148 /* First do special simplification of bit-field references. */
2149 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2150 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2151 optimize_bit_field (x, insn, 0);
2152 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2153 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2154 optimize_bit_field (x, insn, NULL_PTR);
2156 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2157 into a register and then store it back out. */
2158 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2159 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2160 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2161 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2162 > GET_MODE_SIZE (GET_MODE (var))))
2164 replacement = find_fixup_replacement (replacements, var);
2165 if (replacement->new == 0)
2166 replacement->new = gen_reg_rtx (GET_MODE (var));
2168 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2169 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2172 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2173 insn into a pseudo and store the low part of the pseudo into VAR. */
2174 if (GET_CODE (SET_DEST (x)) == SUBREG
2175 && SUBREG_REG (SET_DEST (x)) == var
2176 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2177 > GET_MODE_SIZE (GET_MODE (var))))
2179 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2180 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2187 rtx dest = SET_DEST (x);
2188 rtx src = SET_SRC (x);
2190 rtx outerdest = dest;
2193 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2194 || GET_CODE (dest) == SIGN_EXTRACT
2195 || GET_CODE (dest) == ZERO_EXTRACT)
2196 dest = XEXP (dest, 0);
2198 if (GET_CODE (src) == SUBREG)
2199 src = XEXP (src, 0);
2201 /* If VAR does not appear at the top level of the SET
2202 just scan the lower levels of the tree. */
2204 if (src != var && dest != var)
2207 /* We will need to rerecognize this insn. */
2208 INSN_CODE (insn) = -1;
2211 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var)
2213 /* Since this case will return, ensure we fixup all the
2215 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2216 insn, replacements);
2217 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2218 insn, replacements);
2219 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2220 insn, replacements);
2222 tem = XEXP (outerdest, 0);
2224 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2225 that may appear inside a ZERO_EXTRACT.
2226 This was legitimate when the MEM was a REG. */
2227 if (GET_CODE (tem) == SUBREG
2228 && SUBREG_REG (tem) == var)
2229 tem = fixup_memory_subreg (tem, insn, 0);
2231 tem = fixup_stack_1 (tem, insn);
2233 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2234 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2235 && ! mode_dependent_address_p (XEXP (tem, 0))
2236 && ! MEM_VOLATILE_P (tem))
2238 enum machine_mode wanted_mode;
2239 enum machine_mode is_mode = GET_MODE (tem);
2240 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2242 wanted_mode = insn_data[(int) CODE_FOR_insv].operand[0].mode;
2243 if (wanted_mode == VOIDmode)
2244 wanted_mode = word_mode;
2246 /* If we have a narrower mode, we can do something. */
2247 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2249 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2250 rtx old_pos = XEXP (outerdest, 2);
2253 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2254 offset = (GET_MODE_SIZE (is_mode)
2255 - GET_MODE_SIZE (wanted_mode) - offset);
2257 pos %= GET_MODE_BITSIZE (wanted_mode);
2259 newmem = gen_rtx_MEM (wanted_mode,
2260 plus_constant (XEXP (tem, 0),
2262 MEM_COPY_ATTRIBUTES (newmem, tem);
2264 /* Make the change and see if the insn remains valid. */
2265 INSN_CODE (insn) = -1;
2266 XEXP (outerdest, 0) = newmem;
2267 XEXP (outerdest, 2) = GEN_INT (pos);
2269 if (recog_memoized (insn) >= 0)
2272 /* Otherwise, restore old position. XEXP (x, 0) will be
2274 XEXP (outerdest, 2) = old_pos;
2278 /* If we get here, the bit-field store doesn't allow memory
2279 or isn't located at a constant position. Load the value into
2280 a register, do the store, and put it back into memory. */
2282 tem1 = gen_reg_rtx (GET_MODE (tem));
2283 emit_insn_before (gen_move_insn (tem1, tem), insn);
2284 emit_insn_after (gen_move_insn (tem, tem1), insn);
2285 XEXP (outerdest, 0) = tem1;
2290 /* STRICT_LOW_PART is a no-op on memory references
2291 and it can cause combinations to be unrecognizable,
2294 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2295 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2297 /* A valid insn to copy VAR into or out of a register
2298 must be left alone, to avoid an infinite loop here.
2299 If the reference to VAR is by a subreg, fix that up,
2300 since SUBREG is not valid for a memref.
2301 Also fix up the address of the stack slot.
2303 Note that we must not try to recognize the insn until
2304 after we know that we have valid addresses and no
2305 (subreg (mem ...) ...) constructs, since these interfere
2306 with determining the validity of the insn. */
2308 if ((SET_SRC (x) == var
2309 || (GET_CODE (SET_SRC (x)) == SUBREG
2310 && SUBREG_REG (SET_SRC (x)) == var))
2311 && (GET_CODE (SET_DEST (x)) == REG
2312 || (GET_CODE (SET_DEST (x)) == SUBREG
2313 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2314 && GET_MODE (var) == promoted_mode
2315 && x == single_set (insn))
2319 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2320 if (replacement->new)
2321 SET_SRC (x) = replacement->new;
2322 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2323 SET_SRC (x) = replacement->new
2324 = fixup_memory_subreg (SET_SRC (x), insn, 0);
2326 SET_SRC (x) = replacement->new
2327 = fixup_stack_1 (SET_SRC (x), insn);
2329 if (recog_memoized (insn) >= 0)
2332 /* INSN is not valid, but we know that we want to
2333 copy SET_SRC (x) to SET_DEST (x) in some way. So
2334 we generate the move and see whether it requires more
2335 than one insn. If it does, we emit those insns and
2336 delete INSN. Otherwise, we an just replace the pattern
2337 of INSN; we have already verified above that INSN has
2338 no other function that to do X. */
2340 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2341 if (GET_CODE (pat) == SEQUENCE)
2343 emit_insn_after (pat, insn);
2344 PUT_CODE (insn, NOTE);
2345 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
2346 NOTE_SOURCE_FILE (insn) = 0;
2349 PATTERN (insn) = pat;
2354 if ((SET_DEST (x) == var
2355 || (GET_CODE (SET_DEST (x)) == SUBREG
2356 && SUBREG_REG (SET_DEST (x)) == var))
2357 && (GET_CODE (SET_SRC (x)) == REG
2358 || (GET_CODE (SET_SRC (x)) == SUBREG
2359 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2360 && GET_MODE (var) == promoted_mode
2361 && x == single_set (insn))
2365 if (GET_CODE (SET_DEST (x)) == SUBREG)
2366 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn, 0);
2368 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2370 if (recog_memoized (insn) >= 0)
2373 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2374 if (GET_CODE (pat) == SEQUENCE)
2376 emit_insn_after (pat, insn);
2377 PUT_CODE (insn, NOTE);
2378 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
2379 NOTE_SOURCE_FILE (insn) = 0;
2382 PATTERN (insn) = pat;
2387 /* Otherwise, storing into VAR must be handled specially
2388 by storing into a temporary and copying that into VAR
2389 with a new insn after this one. Note that this case
2390 will be used when storing into a promoted scalar since
2391 the insn will now have different modes on the input
2392 and output and hence will be invalid (except for the case
2393 of setting it to a constant, which does not need any
2394 change if it is valid). We generate extra code in that case,
2395 but combine.c will eliminate it. */
2400 rtx fixeddest = SET_DEST (x);
2402 /* STRICT_LOW_PART can be discarded, around a MEM. */
2403 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2404 fixeddest = XEXP (fixeddest, 0);
2405 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2406 if (GET_CODE (fixeddest) == SUBREG)
2408 fixeddest = fixup_memory_subreg (fixeddest, insn, 0);
2409 promoted_mode = GET_MODE (fixeddest);
2412 fixeddest = fixup_stack_1 (fixeddest, insn);
2414 temp = gen_reg_rtx (promoted_mode);
2416 emit_insn_after (gen_move_insn (fixeddest,
2417 gen_lowpart (GET_MODE (fixeddest),
2421 SET_DEST (x) = temp;
2429 /* Nothing special about this RTX; fix its operands. */
2431 fmt = GET_RTX_FORMAT (code);
2432 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2435 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements);
2436 else if (fmt[i] == 'E')
2439 for (j = 0; j < XVECLEN (x, i); j++)
2440 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2441 insn, replacements);
2446 /* Given X, an rtx of the form (SUBREG:m1 (MEM:m2 addr)),
2447 return an rtx (MEM:m1 newaddr) which is equivalent.
2448 If any insns must be emitted to compute NEWADDR, put them before INSN.
2450 UNCRITICAL nonzero means accept paradoxical subregs.
2451 This is used for subregs found inside REG_NOTES. */
2454 fixup_memory_subreg (x, insn, uncritical)
2459 int offset = SUBREG_WORD (x) * UNITS_PER_WORD;
2460 rtx addr = XEXP (SUBREG_REG (x), 0);
2461 enum machine_mode mode = GET_MODE (x);
2464 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2465 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))
2469 if (BYTES_BIG_ENDIAN)
2470 offset += (MIN (UNITS_PER_WORD, GET_MODE_SIZE (GET_MODE (SUBREG_REG (x))))
2471 - MIN (UNITS_PER_WORD, GET_MODE_SIZE (mode)));
2472 addr = plus_constant (addr, offset);
2473 if (!flag_force_addr && memory_address_p (mode, addr))
2474 /* Shortcut if no insns need be emitted. */
2475 return change_address (SUBREG_REG (x), mode, addr);
2477 result = change_address (SUBREG_REG (x), mode, addr);
2478 emit_insn_before (gen_sequence (), insn);
2483 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2484 Replace subexpressions of X in place.
2485 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2486 Otherwise return X, with its contents possibly altered.
2488 If any insns must be emitted to compute NEWADDR, put them before INSN.
2490 UNCRITICAL is as in fixup_memory_subreg. */
2493 walk_fixup_memory_subreg (x, insn, uncritical)
2498 register enum rtx_code code;
2499 register const char *fmt;
2505 code = GET_CODE (x);
2507 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2508 return fixup_memory_subreg (x, insn, uncritical);
2510 /* Nothing special about this RTX; fix its operands. */
2512 fmt = GET_RTX_FORMAT (code);
2513 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2516 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn, uncritical);
2517 else if (fmt[i] == 'E')
2520 for (j = 0; j < XVECLEN (x, i); j++)
2522 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn, uncritical);
2528 /* For each memory ref within X, if it refers to a stack slot
2529 with an out of range displacement, put the address in a temp register
2530 (emitting new insns before INSN to load these registers)
2531 and alter the memory ref to use that register.
2532 Replace each such MEM rtx with a copy, to avoid clobberage. */
2535 fixup_stack_1 (x, insn)
2540 register RTX_CODE code = GET_CODE (x);
2541 register const char *fmt;
2545 register rtx ad = XEXP (x, 0);
2546 /* If we have address of a stack slot but it's not valid
2547 (displacement is too large), compute the sum in a register. */
2548 if (GET_CODE (ad) == PLUS
2549 && GET_CODE (XEXP (ad, 0)) == REG
2550 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2551 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2552 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2553 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2554 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2556 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2557 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2558 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2559 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2562 if (memory_address_p (GET_MODE (x), ad))
2566 temp = copy_to_reg (ad);
2567 seq = gen_sequence ();
2569 emit_insn_before (seq, insn);
2570 return change_address (x, VOIDmode, temp);
2575 fmt = GET_RTX_FORMAT (code);
2576 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2579 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2580 else if (fmt[i] == 'E')
2583 for (j = 0; j < XVECLEN (x, i); j++)
2584 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2590 /* Optimization: a bit-field instruction whose field
2591 happens to be a byte or halfword in memory
2592 can be changed to a move instruction.
2594 We call here when INSN is an insn to examine or store into a bit-field.
2595 BODY is the SET-rtx to be altered.
2597 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2598 (Currently this is called only from function.c, and EQUIV_MEM
2602 optimize_bit_field (body, insn, equiv_mem)
2607 register rtx bitfield;
2610 enum machine_mode mode;
2612 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2613 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2614 bitfield = SET_DEST (body), destflag = 1;
2616 bitfield = SET_SRC (body), destflag = 0;
2618 /* First check that the field being stored has constant size and position
2619 and is in fact a byte or halfword suitably aligned. */
2621 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2622 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2623 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2625 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2627 register rtx memref = 0;
2629 /* Now check that the containing word is memory, not a register,
2630 and that it is safe to change the machine mode. */
2632 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2633 memref = XEXP (bitfield, 0);
2634 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2636 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2637 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2638 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2639 memref = SUBREG_REG (XEXP (bitfield, 0));
2640 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2642 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2643 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2646 && ! mode_dependent_address_p (XEXP (memref, 0))
2647 && ! MEM_VOLATILE_P (memref))
2649 /* Now adjust the address, first for any subreg'ing
2650 that we are now getting rid of,
2651 and then for which byte of the word is wanted. */
2653 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2656 /* Adjust OFFSET to count bits from low-address byte. */
2657 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2658 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2659 - offset - INTVAL (XEXP (bitfield, 1)));
2661 /* Adjust OFFSET to count bytes from low-address byte. */
2662 offset /= BITS_PER_UNIT;
2663 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2665 offset += SUBREG_WORD (XEXP (bitfield, 0)) * UNITS_PER_WORD;
2666 if (BYTES_BIG_ENDIAN)
2667 offset -= (MIN (UNITS_PER_WORD,
2668 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2669 - MIN (UNITS_PER_WORD,
2670 GET_MODE_SIZE (GET_MODE (memref))));
2674 memref = change_address (memref, mode,
2675 plus_constant (XEXP (memref, 0), offset));
2676 insns = get_insns ();
2678 emit_insns_before (insns, insn);
2680 /* Store this memory reference where
2681 we found the bit field reference. */
2685 validate_change (insn, &SET_DEST (body), memref, 1);
2686 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2688 rtx src = SET_SRC (body);
2689 while (GET_CODE (src) == SUBREG
2690 && SUBREG_WORD (src) == 0)
2691 src = SUBREG_REG (src);
2692 if (GET_MODE (src) != GET_MODE (memref))
2693 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2694 validate_change (insn, &SET_SRC (body), src, 1);
2696 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2697 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2698 /* This shouldn't happen because anything that didn't have
2699 one of these modes should have got converted explicitly
2700 and then referenced through a subreg.
2701 This is so because the original bit-field was
2702 handled by agg_mode and so its tree structure had
2703 the same mode that memref now has. */
2708 rtx dest = SET_DEST (body);
2710 while (GET_CODE (dest) == SUBREG
2711 && SUBREG_WORD (dest) == 0
2712 && (GET_MODE_CLASS (GET_MODE (dest))
2713 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2714 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2716 dest = SUBREG_REG (dest);
2718 validate_change (insn, &SET_DEST (body), dest, 1);
2720 if (GET_MODE (dest) == GET_MODE (memref))
2721 validate_change (insn, &SET_SRC (body), memref, 1);
2724 /* Convert the mem ref to the destination mode. */
2725 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2728 convert_move (newreg, memref,
2729 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2733 validate_change (insn, &SET_SRC (body), newreg, 1);
2737 /* See if we can convert this extraction or insertion into
2738 a simple move insn. We might not be able to do so if this
2739 was, for example, part of a PARALLEL.
2741 If we succeed, write out any needed conversions. If we fail,
2742 it is hard to guess why we failed, so don't do anything
2743 special; just let the optimization be suppressed. */
2745 if (apply_change_group () && seq)
2746 emit_insns_before (seq, insn);
2751 /* These routines are responsible for converting virtual register references
2752 to the actual hard register references once RTL generation is complete.
2754 The following four variables are used for communication between the
2755 routines. They contain the offsets of the virtual registers from their
2756 respective hard registers. */
2758 static int in_arg_offset;
2759 static int var_offset;
2760 static int dynamic_offset;
2761 static int out_arg_offset;
2762 static int cfa_offset;
2764 /* In most machines, the stack pointer register is equivalent to the bottom
2767 #ifndef STACK_POINTER_OFFSET
2768 #define STACK_POINTER_OFFSET 0
2771 /* If not defined, pick an appropriate default for the offset of dynamically
2772 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2773 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2775 #ifndef STACK_DYNAMIC_OFFSET
2777 /* The bottom of the stack points to the actual arguments. If
2778 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2779 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2780 stack space for register parameters is not pushed by the caller, but
2781 rather part of the fixed stack areas and hence not included in
2782 `current_function_outgoing_args_size'. Nevertheless, we must allow
2783 for it when allocating stack dynamic objects. */
2785 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2786 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2787 ((ACCUMULATE_OUTGOING_ARGS \
2788 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2789 + (STACK_POINTER_OFFSET)) \
2792 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2793 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2794 + (STACK_POINTER_OFFSET))
2798 /* On most machines, the CFA coincides with the first incoming parm. */
2800 #ifndef ARG_POINTER_CFA_OFFSET
2801 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2804 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just had
2805 its address taken. DECL is the decl for the object stored in the
2806 register, for later use if we do need to force REG into the stack.
2807 REG is overwritten by the MEM like in put_reg_into_stack. */
2810 gen_mem_addressof (reg, decl)
2814 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2817 /* If the original REG was a user-variable, then so is the REG whose
2818 address is being taken. Likewise for unchanging. */
2819 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2820 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2822 PUT_CODE (reg, MEM);
2826 tree type = TREE_TYPE (decl);
2828 PUT_MODE (reg, DECL_MODE (decl));
2829 MEM_VOLATILE_P (reg) = TREE_SIDE_EFFECTS (decl);
2830 MEM_SET_IN_STRUCT_P (reg, AGGREGATE_TYPE_P (type));
2831 MEM_ALIAS_SET (reg) = get_alias_set (decl);
2833 if (TREE_USED (decl) || DECL_INITIAL (decl) != 0)
2834 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), 0);
2838 /* We have no alias information about this newly created MEM. */
2839 MEM_ALIAS_SET (reg) = 0;
2841 fixup_var_refs (reg, GET_MODE (reg), 0, 0);
2847 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2850 flush_addressof (decl)
2853 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2854 && DECL_RTL (decl) != 0
2855 && GET_CODE (DECL_RTL (decl)) == MEM
2856 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2857 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2858 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2861 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2864 put_addressof_into_stack (r, ht)
2866 struct hash_table *ht;
2869 int volatile_p, used_p;
2871 rtx reg = XEXP (r, 0);
2873 if (GET_CODE (reg) != REG)
2876 decl = ADDRESSOF_DECL (r);
2879 type = TREE_TYPE (decl);
2880 volatile_p = (TREE_CODE (decl) != SAVE_EXPR
2881 && TREE_THIS_VOLATILE (decl));
2882 used_p = (TREE_USED (decl)
2883 || (TREE_CODE (decl) != SAVE_EXPR
2884 && DECL_INITIAL (decl) != 0));
2893 put_reg_into_stack (0, reg, type, GET_MODE (reg), GET_MODE (reg),
2894 volatile_p, ADDRESSOF_REGNO (r), used_p, ht);
2897 /* List of replacements made below in purge_addressof_1 when creating
2898 bitfield insertions. */
2899 static rtx purge_bitfield_addressof_replacements;
2901 /* List of replacements made below in purge_addressof_1 for patterns
2902 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2903 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2904 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2905 enough in complex cases, e.g. when some field values can be
2906 extracted by usage MEM with narrower mode. */
2907 static rtx purge_addressof_replacements;
2909 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2910 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2911 the stack. If the function returns FALSE then the replacement could not
2915 purge_addressof_1 (loc, insn, force, store, ht)
2919 struct hash_table *ht;
2925 boolean result = true;
2927 /* Re-start here to avoid recursion in common cases. */
2934 code = GET_CODE (x);
2936 /* If we don't return in any of the cases below, we will recurse inside
2937 the RTX, which will normally result in any ADDRESSOF being forced into
2941 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1, ht);
2942 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0, ht);
2946 else if (code == ADDRESSOF && GET_CODE (XEXP (x, 0)) == MEM)
2948 /* We must create a copy of the rtx because it was created by
2949 overwriting a REG rtx which is always shared. */
2950 rtx sub = copy_rtx (XEXP (XEXP (x, 0), 0));
2953 if (validate_change (insn, loc, sub, 0)
2954 || validate_replace_rtx (x, sub, insn))
2958 sub = force_operand (sub, NULL_RTX);
2959 if (! validate_change (insn, loc, sub, 0)
2960 && ! validate_replace_rtx (x, sub, insn))
2963 insns = gen_sequence ();
2965 emit_insn_before (insns, insn);
2969 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
2971 rtx sub = XEXP (XEXP (x, 0), 0);
2974 if (GET_CODE (sub) == MEM)
2976 sub2 = gen_rtx_MEM (GET_MODE (x), copy_rtx (XEXP (sub, 0)));
2977 MEM_COPY_ATTRIBUTES (sub2, sub);
2980 else if (GET_CODE (sub) == REG
2981 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
2983 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
2985 int size_x, size_sub;
2989 /* When processing REG_NOTES look at the list of
2990 replacements done on the insn to find the register that X
2994 for (tem = purge_bitfield_addressof_replacements;
2996 tem = XEXP (XEXP (tem, 1), 1))
2997 if (rtx_equal_p (x, XEXP (tem, 0)))
2999 *loc = XEXP (XEXP (tem, 1), 0);
3003 /* See comment for purge_addressof_replacements. */
3004 for (tem = purge_addressof_replacements;
3006 tem = XEXP (XEXP (tem, 1), 1))
3007 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3009 rtx z = XEXP (XEXP (tem, 1), 0);
3011 if (GET_MODE (x) == GET_MODE (z)
3012 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
3013 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
3016 /* It can happen that the note may speak of things
3017 in a wider (or just different) mode than the
3018 code did. This is especially true of
3021 if (GET_CODE (z) == SUBREG && SUBREG_WORD (z) == 0)
3024 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3025 && (GET_MODE_SIZE (GET_MODE (x))
3026 > GET_MODE_SIZE (GET_MODE (z))))
3028 /* This can occur as a result in invalid
3029 pointer casts, e.g. float f; ...
3030 *(long long int *)&f.
3031 ??? We could emit a warning here, but
3032 without a line number that wouldn't be
3034 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
3037 z = gen_lowpart (GET_MODE (x), z);
3043 /* Sometimes we may not be able to find the replacement. For
3044 example when the original insn was a MEM in a wider mode,
3045 and the note is part of a sign extension of a narrowed
3046 version of that MEM. Gcc testcase compile/990829-1.c can
3047 generate an example of this siutation. Rather than complain
3048 we return false, which will prompt our caller to remove the
3053 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3054 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3056 /* Don't even consider working with paradoxical subregs,
3057 or the moral equivalent seen here. */
3058 if (size_x <= size_sub
3059 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3061 /* Do a bitfield insertion to mirror what would happen
3068 rtx p = PREV_INSN (insn);
3071 val = gen_reg_rtx (GET_MODE (x));
3072 if (! validate_change (insn, loc, val, 0))
3074 /* Discard the current sequence and put the
3075 ADDRESSOF on stack. */
3079 seq = gen_sequence ();
3081 emit_insn_before (seq, insn);
3082 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3086 store_bit_field (sub, size_x, 0, GET_MODE (x),
3087 val, GET_MODE_SIZE (GET_MODE (sub)),
3088 GET_MODE_ALIGNMENT (GET_MODE (sub)));
3090 /* Make sure to unshare any shared rtl that store_bit_field
3091 might have created. */
3092 unshare_all_rtl_again (get_insns ());
3094 seq = gen_sequence ();
3096 p = emit_insn_after (seq, insn);
3097 if (NEXT_INSN (insn))
3098 compute_insns_for_mem (NEXT_INSN (insn),
3099 p ? NEXT_INSN (p) : NULL_RTX,
3104 rtx p = PREV_INSN (insn);
3107 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3108 GET_MODE (x), GET_MODE (x),
3109 GET_MODE_SIZE (GET_MODE (sub)),
3110 GET_MODE_SIZE (GET_MODE (sub)));
3112 if (! validate_change (insn, loc, val, 0))
3114 /* Discard the current sequence and put the
3115 ADDRESSOF on stack. */
3120 seq = gen_sequence ();
3122 emit_insn_before (seq, insn);
3123 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3127 /* Remember the replacement so that the same one can be done
3128 on the REG_NOTES. */
3129 purge_bitfield_addressof_replacements
3130 = gen_rtx_EXPR_LIST (VOIDmode, x,
3133 purge_bitfield_addressof_replacements));
3135 /* We replaced with a reg -- all done. */
3140 else if (validate_change (insn, loc, sub, 0))
3142 /* Remember the replacement so that the same one can be done
3143 on the REG_NOTES. */
3144 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3148 for (tem = purge_addressof_replacements;
3150 tem = XEXP (XEXP (tem, 1), 1))
3151 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3153 XEXP (XEXP (tem, 1), 0) = sub;
3156 purge_addressof_replacements
3157 = gen_rtx (EXPR_LIST, VOIDmode, XEXP (x, 0),
3158 gen_rtx_EXPR_LIST (VOIDmode, sub,
3159 purge_addressof_replacements));
3165 /* else give up and put it into the stack */
3168 else if (code == ADDRESSOF)
3170 put_addressof_into_stack (x, ht);
3173 else if (code == SET)
3175 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1, ht);
3176 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0, ht);
3180 /* Scan all subexpressions. */
3181 fmt = GET_RTX_FORMAT (code);
3182 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3185 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0, ht);
3186 else if (*fmt == 'E')
3187 for (j = 0; j < XVECLEN (x, i); j++)
3188 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0, ht);
3194 /* Return a new hash table entry in HT. */
3196 static struct hash_entry *
3197 insns_for_mem_newfunc (he, ht, k)
3198 struct hash_entry *he;
3199 struct hash_table *ht;
3200 hash_table_key k ATTRIBUTE_UNUSED;
3202 struct insns_for_mem_entry *ifmhe;
3206 ifmhe = ((struct insns_for_mem_entry *)
3207 hash_allocate (ht, sizeof (struct insns_for_mem_entry)));
3208 ifmhe->insns = NULL_RTX;
3213 /* Return a hash value for K, a REG. */
3215 static unsigned long
3216 insns_for_mem_hash (k)
3219 /* K is really a RTX. Just use the address as the hash value. */
3220 return (unsigned long) k;
3223 /* Return non-zero if K1 and K2 (two REGs) are the same. */
3226 insns_for_mem_comp (k1, k2)
3233 struct insns_for_mem_walk_info {
3234 /* The hash table that we are using to record which INSNs use which
3236 struct hash_table *ht;
3238 /* The INSN we are currently proessing. */
3241 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3242 to find the insns that use the REGs in the ADDRESSOFs. */
3246 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3247 that might be used in an ADDRESSOF expression, record this INSN in
3248 the hash table given by DATA (which is really a pointer to an
3249 insns_for_mem_walk_info structure). */
3252 insns_for_mem_walk (r, data)
3256 struct insns_for_mem_walk_info *ifmwi
3257 = (struct insns_for_mem_walk_info *) data;
3259 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3260 && GET_CODE (XEXP (*r, 0)) == REG)
3261 hash_lookup (ifmwi->ht, XEXP (*r, 0), /*create=*/1, /*copy=*/0);
3262 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3264 /* Lookup this MEM in the hashtable, creating it if necessary. */
3265 struct insns_for_mem_entry *ifme
3266 = (struct insns_for_mem_entry *) hash_lookup (ifmwi->ht,
3271 /* If we have not already recorded this INSN, do so now. Since
3272 we process the INSNs in order, we know that if we have
3273 recorded it it must be at the front of the list. */
3274 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3276 /* We do the allocation on the same obstack as is used for
3277 the hash table since this memory will not be used once
3278 the hash table is deallocated. */
3279 push_obstacks (&ifmwi->ht->memory, &ifmwi->ht->memory);
3280 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3289 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3290 which REGs in HT. */
3293 compute_insns_for_mem (insns, last_insn, ht)
3296 struct hash_table *ht;
3299 struct insns_for_mem_walk_info ifmwi;
3302 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3303 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3307 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3311 /* Helper function for purge_addressof called through for_each_rtx.
3312 Returns true iff the rtl is an ADDRESSOF. */
3314 is_addressof (rtl, data)
3316 void *data ATTRIBUTE_UNUSED;
3318 return GET_CODE (*rtl) == ADDRESSOF;
3321 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3322 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3326 purge_addressof (insns)
3330 struct hash_table ht;
3332 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3333 requires a fixup pass over the instruction stream to correct
3334 INSNs that depended on the REG being a REG, and not a MEM. But,
3335 these fixup passes are slow. Furthermore, most MEMs are not
3336 mentioned in very many instructions. So, we speed up the process
3337 by pre-calculating which REGs occur in which INSNs; that allows
3338 us to perform the fixup passes much more quickly. */
3339 hash_table_init (&ht,
3340 insns_for_mem_newfunc,
3342 insns_for_mem_comp);
3343 compute_insns_for_mem (insns, NULL_RTX, &ht);
3345 for (insn = insns; insn; insn = NEXT_INSN (insn))
3346 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3347 || GET_CODE (insn) == CALL_INSN)
3349 if (! purge_addressof_1 (&PATTERN (insn), insn,
3350 asm_noperands (PATTERN (insn)) > 0, 0, &ht))
3351 /* If we could not replace the ADDRESSOFs in the insn,
3352 something is wrong. */
3355 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, &ht))
3357 /* If we could not replace the ADDRESSOFs in the insn's notes,
3358 we can just remove the offending notes instead. */
3361 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3363 /* If we find a REG_RETVAL note then the insn is a libcall.
3364 Such insns must have REG_EQUAL notes as well, in order
3365 for later passes of the compiler to work. So it is not
3366 safe to delete the notes here, and instead we abort. */
3367 if (REG_NOTE_KIND (note) == REG_RETVAL)
3369 if (for_each_rtx (¬e, is_addressof, NULL))
3370 remove_note (insn, note);
3376 hash_table_free (&ht);
3377 purge_bitfield_addressof_replacements = 0;
3378 purge_addressof_replacements = 0;
3380 /* REGs are shared. purge_addressof will destructively replace a REG
3381 with a MEM, which creates shared MEMs.
3383 Unfortunately, the children of put_reg_into_stack assume that MEMs
3384 referring to the same stack slot are shared (fixup_var_refs and
3385 the associated hash table code).
3387 So, we have to do another unsharing pass after we have flushed any
3388 REGs that had their address taken into the stack.
3390 It may be worth tracking whether or not we converted any REGs into
3391 MEMs to avoid this overhead when it is not needed. */
3392 unshare_all_rtl_again (get_insns ());
3395 /* Pass through the INSNS of function FNDECL and convert virtual register
3396 references to hard register references. */
3399 instantiate_virtual_regs (fndecl, insns)
3406 /* Compute the offsets to use for this function. */
3407 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3408 var_offset = STARTING_FRAME_OFFSET;
3409 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3410 out_arg_offset = STACK_POINTER_OFFSET;
3411 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl);
3413 /* Scan all variables and parameters of this function. For each that is
3414 in memory, instantiate all virtual registers if the result is a valid
3415 address. If not, we do it later. That will handle most uses of virtual
3416 regs on many machines. */
3417 instantiate_decls (fndecl, 1);
3419 /* Initialize recognition, indicating that volatile is OK. */
3422 /* Scan through all the insns, instantiating every virtual register still
3424 for (insn = insns; insn; insn = NEXT_INSN (insn))
3425 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3426 || GET_CODE (insn) == CALL_INSN)
3428 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3429 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3432 /* Instantiate the stack slots for the parm registers, for later use in
3433 addressof elimination. */
3434 for (i = 0; i < max_parm_reg; ++i)
3435 if (parm_reg_stack_loc[i])
3436 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3438 /* Now instantiate the remaining register equivalences for debugging info.
3439 These will not be valid addresses. */
3440 instantiate_decls (fndecl, 0);
3442 /* Indicate that, from now on, assign_stack_local should use
3443 frame_pointer_rtx. */
3444 virtuals_instantiated = 1;
3447 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3448 all virtual registers in their DECL_RTL's.
3450 If VALID_ONLY, do this only if the resulting address is still valid.
3451 Otherwise, always do it. */
3454 instantiate_decls (fndecl, valid_only)
3460 if (DECL_SAVED_INSNS (fndecl))
3461 /* When compiling an inline function, the obstack used for
3462 rtl allocation is the maybepermanent_obstack. Calling
3463 `resume_temporary_allocation' switches us back to that
3464 obstack while we process this function's parameters. */
3465 resume_temporary_allocation ();
3467 /* Process all parameters of the function. */
3468 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3470 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3472 instantiate_decl (DECL_RTL (decl), size, valid_only);
3474 /* If the parameter was promoted, then the incoming RTL mode may be
3475 larger than the declared type size. We must use the larger of
3477 size = MAX (GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl))), size);
3478 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3481 /* Now process all variables defined in the function or its subblocks. */
3482 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3484 if (DECL_INLINE (fndecl) || DECL_DEFER_OUTPUT (fndecl))
3486 /* Save all rtl allocated for this function by raising the
3487 high-water mark on the maybepermanent_obstack. */
3489 /* All further rtl allocation is now done in the current_obstack. */
3490 rtl_in_current_obstack ();
3494 /* Subroutine of instantiate_decls: Process all decls in the given
3495 BLOCK node and all its subblocks. */
3498 instantiate_decls_1 (let, valid_only)
3504 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3505 instantiate_decl (DECL_RTL (t), int_size_in_bytes (TREE_TYPE (t)),
3508 /* Process all subblocks. */
3509 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3510 instantiate_decls_1 (t, valid_only);
3513 /* Subroutine of the preceding procedures: Given RTL representing a
3514 decl and the size of the object, do any instantiation required.
3516 If VALID_ONLY is non-zero, it means that the RTL should only be
3517 changed if the new address is valid. */
3520 instantiate_decl (x, size, valid_only)
3525 enum machine_mode mode;
3528 /* If this is not a MEM, no need to do anything. Similarly if the
3529 address is a constant or a register that is not a virtual register. */
3531 if (x == 0 || GET_CODE (x) != MEM)
3535 if (CONSTANT_P (addr)
3536 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3537 || (GET_CODE (addr) == REG
3538 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3539 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3542 /* If we should only do this if the address is valid, copy the address.
3543 We need to do this so we can undo any changes that might make the
3544 address invalid. This copy is unfortunate, but probably can't be
3548 addr = copy_rtx (addr);
3550 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3552 if (valid_only && size >= 0)
3554 unsigned HOST_WIDE_INT decl_size = size;
3556 /* Now verify that the resulting address is valid for every integer or
3557 floating-point mode up to and including SIZE bytes long. We do this
3558 since the object might be accessed in any mode and frame addresses
3561 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3562 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3563 mode = GET_MODE_WIDER_MODE (mode))
3564 if (! memory_address_p (mode, addr))
3567 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3568 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3569 mode = GET_MODE_WIDER_MODE (mode))
3570 if (! memory_address_p (mode, addr))
3574 /* Put back the address now that we have updated it and we either know
3575 it is valid or we don't care whether it is valid. */
3580 /* Given a pointer to a piece of rtx and an optional pointer to the
3581 containing object, instantiate any virtual registers present in it.
3583 If EXTRA_INSNS, we always do the replacement and generate
3584 any extra insns before OBJECT. If it zero, we do nothing if replacement
3587 Return 1 if we either had nothing to do or if we were able to do the
3588 needed replacement. Return 0 otherwise; we only return zero if
3589 EXTRA_INSNS is zero.
3591 We first try some simple transformations to avoid the creation of extra
3595 instantiate_virtual_regs_1 (loc, object, extra_insns)
3603 HOST_WIDE_INT offset = 0;
3609 /* Re-start here to avoid recursion in common cases. */
3616 code = GET_CODE (x);
3618 /* Check for some special cases. */
3635 /* We are allowed to set the virtual registers. This means that
3636 the actual register should receive the source minus the
3637 appropriate offset. This is used, for example, in the handling
3638 of non-local gotos. */
3639 if (SET_DEST (x) == virtual_incoming_args_rtx)
3640 new = arg_pointer_rtx, offset = -in_arg_offset;
3641 else if (SET_DEST (x) == virtual_stack_vars_rtx)
3642 new = frame_pointer_rtx, offset = -var_offset;
3643 else if (SET_DEST (x) == virtual_stack_dynamic_rtx)
3644 new = stack_pointer_rtx, offset = -dynamic_offset;
3645 else if (SET_DEST (x) == virtual_outgoing_args_rtx)
3646 new = stack_pointer_rtx, offset = -out_arg_offset;
3647 else if (SET_DEST (x) == virtual_cfa_rtx)
3648 new = arg_pointer_rtx, offset = -cfa_offset;
3652 rtx src = SET_SRC (x);
3654 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3656 /* The only valid sources here are PLUS or REG. Just do
3657 the simplest possible thing to handle them. */
3658 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3662 if (GET_CODE (src) != REG)
3663 temp = force_operand (src, NULL_RTX);
3666 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3670 emit_insns_before (seq, object);
3673 if (! validate_change (object, &SET_SRC (x), temp, 0)
3680 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3685 /* Handle special case of virtual register plus constant. */
3686 if (CONSTANT_P (XEXP (x, 1)))
3688 rtx old, new_offset;
3690 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3691 if (GET_CODE (XEXP (x, 0)) == PLUS)
3693 rtx inner = XEXP (XEXP (x, 0), 0);
3695 if (inner == virtual_incoming_args_rtx)
3696 new = arg_pointer_rtx, offset = in_arg_offset;
3697 else if (inner == virtual_stack_vars_rtx)
3698 new = frame_pointer_rtx, offset = var_offset;
3699 else if (inner == virtual_stack_dynamic_rtx)
3700 new = stack_pointer_rtx, offset = dynamic_offset;
3701 else if (inner == virtual_outgoing_args_rtx)
3702 new = stack_pointer_rtx, offset = out_arg_offset;
3703 else if (inner == virtual_cfa_rtx)
3704 new = arg_pointer_rtx, offset = cfa_offset;
3711 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3713 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3716 else if (XEXP (x, 0) == virtual_incoming_args_rtx)
3717 new = arg_pointer_rtx, offset = in_arg_offset;
3718 else if (XEXP (x, 0) == virtual_stack_vars_rtx)
3719 new = frame_pointer_rtx, offset = var_offset;
3720 else if (XEXP (x, 0) == virtual_stack_dynamic_rtx)
3721 new = stack_pointer_rtx, offset = dynamic_offset;
3722 else if (XEXP (x, 0) == virtual_outgoing_args_rtx)
3723 new = stack_pointer_rtx, offset = out_arg_offset;
3724 else if (XEXP (x, 0) == virtual_cfa_rtx)
3725 new = arg_pointer_rtx, offset = cfa_offset;
3728 /* We know the second operand is a constant. Unless the
3729 first operand is a REG (which has been already checked),
3730 it needs to be checked. */
3731 if (GET_CODE (XEXP (x, 0)) != REG)
3739 new_offset = plus_constant (XEXP (x, 1), offset);
3741 /* If the new constant is zero, try to replace the sum with just
3743 if (new_offset == const0_rtx
3744 && validate_change (object, loc, new, 0))
3747 /* Next try to replace the register and new offset.
3748 There are two changes to validate here and we can't assume that
3749 in the case of old offset equals new just changing the register
3750 will yield a valid insn. In the interests of a little efficiency,
3751 however, we only call validate change once (we don't queue up the
3752 changes and then call apply_change_group). */
3756 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3757 : (XEXP (x, 0) = new,
3758 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3766 /* Otherwise copy the new constant into a register and replace
3767 constant with that register. */
3768 temp = gen_reg_rtx (Pmode);
3770 if (validate_change (object, &XEXP (x, 1), temp, 0))
3771 emit_insn_before (gen_move_insn (temp, new_offset), object);
3774 /* If that didn't work, replace this expression with a
3775 register containing the sum. */
3778 new = gen_rtx_PLUS (Pmode, new, new_offset);
3781 temp = force_operand (new, NULL_RTX);
3785 emit_insns_before (seq, object);
3786 if (! validate_change (object, loc, temp, 0)
3787 && ! validate_replace_rtx (x, temp, object))
3795 /* Fall through to generic two-operand expression case. */
3801 case DIV: case UDIV:
3802 case MOD: case UMOD:
3803 case AND: case IOR: case XOR:
3804 case ROTATERT: case ROTATE:
3805 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3807 case GE: case GT: case GEU: case GTU:
3808 case LE: case LT: case LEU: case LTU:
3809 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3810 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3815 /* Most cases of MEM that convert to valid addresses have already been
3816 handled by our scan of decls. The only special handling we
3817 need here is to make a copy of the rtx to ensure it isn't being
3818 shared if we have to change it to a pseudo.
3820 If the rtx is a simple reference to an address via a virtual register,
3821 it can potentially be shared. In such cases, first try to make it
3822 a valid address, which can also be shared. Otherwise, copy it and
3825 First check for common cases that need no processing. These are
3826 usually due to instantiation already being done on a previous instance
3830 if (CONSTANT_ADDRESS_P (temp)
3831 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3832 || temp == arg_pointer_rtx
3834 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3835 || temp == hard_frame_pointer_rtx
3837 || temp == frame_pointer_rtx)
3840 if (GET_CODE (temp) == PLUS
3841 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3842 && (XEXP (temp, 0) == frame_pointer_rtx
3843 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3844 || XEXP (temp, 0) == hard_frame_pointer_rtx
3846 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3847 || XEXP (temp, 0) == arg_pointer_rtx
3852 if (temp == virtual_stack_vars_rtx
3853 || temp == virtual_incoming_args_rtx
3854 || (GET_CODE (temp) == PLUS
3855 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3856 && (XEXP (temp, 0) == virtual_stack_vars_rtx
3857 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
3859 /* This MEM may be shared. If the substitution can be done without
3860 the need to generate new pseudos, we want to do it in place
3861 so all copies of the shared rtx benefit. The call below will
3862 only make substitutions if the resulting address is still
3865 Note that we cannot pass X as the object in the recursive call
3866 since the insn being processed may not allow all valid
3867 addresses. However, if we were not passed on object, we can
3868 only modify X without copying it if X will have a valid
3871 ??? Also note that this can still lose if OBJECT is an insn that
3872 has less restrictions on an address that some other insn.
3873 In that case, we will modify the shared address. This case
3874 doesn't seem very likely, though. One case where this could
3875 happen is in the case of a USE or CLOBBER reference, but we
3876 take care of that below. */
3878 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
3879 object ? object : x, 0))
3882 /* Otherwise make a copy and process that copy. We copy the entire
3883 RTL expression since it might be a PLUS which could also be
3885 *loc = x = copy_rtx (x);
3888 /* Fall through to generic unary operation case. */
3890 case STRICT_LOW_PART:
3892 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
3893 case SIGN_EXTEND: case ZERO_EXTEND:
3894 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
3895 case FLOAT: case FIX:
3896 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
3900 /* These case either have just one operand or we know that we need not
3901 check the rest of the operands. */
3907 /* If the operand is a MEM, see if the change is a valid MEM. If not,
3908 go ahead and make the invalid one, but do it to a copy. For a REG,
3909 just make the recursive call, since there's no chance of a problem. */
3911 if ((GET_CODE (XEXP (x, 0)) == MEM
3912 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
3914 || (GET_CODE (XEXP (x, 0)) == REG
3915 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
3918 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
3923 /* Try to replace with a PLUS. If that doesn't work, compute the sum
3924 in front of this insn and substitute the temporary. */
3925 if (x == virtual_incoming_args_rtx)
3926 new = arg_pointer_rtx, offset = in_arg_offset;
3927 else if (x == virtual_stack_vars_rtx)
3928 new = frame_pointer_rtx, offset = var_offset;
3929 else if (x == virtual_stack_dynamic_rtx)
3930 new = stack_pointer_rtx, offset = dynamic_offset;
3931 else if (x == virtual_outgoing_args_rtx)
3932 new = stack_pointer_rtx, offset = out_arg_offset;
3933 else if (x == virtual_cfa_rtx)
3934 new = arg_pointer_rtx, offset = cfa_offset;
3938 temp = plus_constant (new, offset);
3939 if (!validate_change (object, loc, temp, 0))
3945 temp = force_operand (temp, NULL_RTX);
3949 emit_insns_before (seq, object);
3950 if (! validate_change (object, loc, temp, 0)
3951 && ! validate_replace_rtx (x, temp, object))
3959 if (GET_CODE (XEXP (x, 0)) == REG)
3962 else if (GET_CODE (XEXP (x, 0)) == MEM)
3964 /* If we have a (addressof (mem ..)), do any instantiation inside
3965 since we know we'll be making the inside valid when we finally
3966 remove the ADDRESSOF. */
3967 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
3976 /* Scan all subexpressions. */
3977 fmt = GET_RTX_FORMAT (code);
3978 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3981 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
3984 else if (*fmt == 'E')
3985 for (j = 0; j < XVECLEN (x, i); j++)
3986 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
3993 /* Optimization: assuming this function does not receive nonlocal gotos,
3994 delete the handlers for such, as well as the insns to establish
3995 and disestablish them. */
4001 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4003 /* Delete the handler by turning off the flag that would
4004 prevent jump_optimize from deleting it.
4005 Also permit deletion of the nonlocal labels themselves
4006 if nothing local refers to them. */
4007 if (GET_CODE (insn) == CODE_LABEL)
4011 LABEL_PRESERVE_P (insn) = 0;
4013 /* Remove it from the nonlocal_label list, to avoid confusing
4015 for (t = nonlocal_labels, last_t = 0; t;
4016 last_t = t, t = TREE_CHAIN (t))
4017 if (DECL_RTL (TREE_VALUE (t)) == insn)
4022 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
4024 TREE_CHAIN (last_t) = TREE_CHAIN (t);
4027 if (GET_CODE (insn) == INSN)
4031 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
4032 if (reg_mentioned_p (t, PATTERN (insn)))
4038 || (nonlocal_goto_stack_level != 0
4039 && reg_mentioned_p (nonlocal_goto_stack_level,
4049 return max_parm_reg;
4052 /* Return the first insn following those generated by `assign_parms'. */
4055 get_first_nonparm_insn ()
4058 return NEXT_INSN (last_parm_insn);
4059 return get_insns ();
4062 /* Return the first NOTE_INSN_BLOCK_BEG note in the function.
4063 Crash if there is none. */
4066 get_first_block_beg ()
4068 register rtx searcher;
4069 register rtx insn = get_first_nonparm_insn ();
4071 for (searcher = insn; searcher; searcher = NEXT_INSN (searcher))
4072 if (GET_CODE (searcher) == NOTE
4073 && NOTE_LINE_NUMBER (searcher) == NOTE_INSN_BLOCK_BEG)
4076 abort (); /* Invalid call to this function. (See comments above.) */
4080 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4081 This means a type for which function calls must pass an address to the
4082 function or get an address back from the function.
4083 EXP may be a type node or an expression (whose type is tested). */
4086 aggregate_value_p (exp)
4089 int i, regno, nregs;
4092 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4094 if (TREE_CODE (type) == VOID_TYPE)
4096 if (RETURN_IN_MEMORY (type))
4098 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4099 and thus can't be returned in registers. */
4100 if (TREE_ADDRESSABLE (type))
4102 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4104 /* Make sure we have suitable call-clobbered regs to return
4105 the value in; if not, we must return it in memory. */
4106 reg = hard_function_value (type, 0, 0);
4108 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4110 if (GET_CODE (reg) != REG)
4113 regno = REGNO (reg);
4114 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
4115 for (i = 0; i < nregs; i++)
4116 if (! call_used_regs[regno + i])
4121 /* Assign RTL expressions to the function's parameters.
4122 This may involve copying them into registers and using
4123 those registers as the RTL for them. */
4126 assign_parms (fndecl)
4130 register rtx entry_parm = 0;
4131 register rtx stack_parm = 0;
4132 CUMULATIVE_ARGS args_so_far;
4133 enum machine_mode promoted_mode, passed_mode;
4134 enum machine_mode nominal_mode, promoted_nominal_mode;
4136 /* Total space needed so far for args on the stack,
4137 given as a constant and a tree-expression. */
4138 struct args_size stack_args_size;
4139 tree fntype = TREE_TYPE (fndecl);
4140 tree fnargs = DECL_ARGUMENTS (fndecl);
4141 /* This is used for the arg pointer when referring to stack args. */
4142 rtx internal_arg_pointer;
4143 /* This is a dummy PARM_DECL that we used for the function result if
4144 the function returns a structure. */
4145 tree function_result_decl = 0;
4146 #ifdef SETUP_INCOMING_VARARGS
4147 int varargs_setup = 0;
4149 rtx conversion_insns = 0;
4150 struct args_size alignment_pad;
4152 /* Nonzero if the last arg is named `__builtin_va_alist',
4153 which is used on some machines for old-fashioned non-ANSI varargs.h;
4154 this should be stuck onto the stack as if it had arrived there. */
4156 = (current_function_varargs
4158 && (parm = tree_last (fnargs)) != 0
4160 && (! strcmp (IDENTIFIER_POINTER (DECL_NAME (parm)),
4161 "__builtin_va_alist")));
4163 /* Nonzero if function takes extra anonymous args.
4164 This means the last named arg must be on the stack
4165 right before the anonymous ones. */
4167 = (TYPE_ARG_TYPES (fntype) != 0
4168 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4169 != void_type_node));
4171 current_function_stdarg = stdarg;
4173 /* If the reg that the virtual arg pointer will be translated into is
4174 not a fixed reg or is the stack pointer, make a copy of the virtual
4175 arg pointer, and address parms via the copy. The frame pointer is
4176 considered fixed even though it is not marked as such.
4178 The second time through, simply use ap to avoid generating rtx. */
4180 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4181 || ! (fixed_regs[ARG_POINTER_REGNUM]
4182 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4183 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4185 internal_arg_pointer = virtual_incoming_args_rtx;
4186 current_function_internal_arg_pointer = internal_arg_pointer;
4188 stack_args_size.constant = 0;
4189 stack_args_size.var = 0;
4191 /* If struct value address is treated as the first argument, make it so. */
4192 if (aggregate_value_p (DECL_RESULT (fndecl))
4193 && ! current_function_returns_pcc_struct
4194 && struct_value_incoming_rtx == 0)
4196 tree type = build_pointer_type (TREE_TYPE (fntype));
4198 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4200 DECL_ARG_TYPE (function_result_decl) = type;
4201 TREE_CHAIN (function_result_decl) = fnargs;
4202 fnargs = function_result_decl;
4205 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4206 parm_reg_stack_loc = (rtx *) xcalloc (max_parm_reg, sizeof (rtx));
4208 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4209 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4211 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, 0);
4214 /* We haven't yet found an argument that we must push and pretend the
4216 current_function_pretend_args_size = 0;
4218 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4220 struct args_size stack_offset;
4221 struct args_size arg_size;
4222 int passed_pointer = 0;
4223 int did_conversion = 0;
4224 tree passed_type = DECL_ARG_TYPE (parm);
4225 tree nominal_type = TREE_TYPE (parm);
4228 /* Set LAST_NAMED if this is last named arg before some
4230 int last_named = ((TREE_CHAIN (parm) == 0
4231 || DECL_NAME (TREE_CHAIN (parm)) == 0)
4232 && (stdarg || current_function_varargs));
4233 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4234 most machines, if this is a varargs/stdarg function, then we treat
4235 the last named arg as if it were anonymous too. */
4236 int named_arg = STRICT_ARGUMENT_NAMING ? 1 : ! last_named;
4238 if (TREE_TYPE (parm) == error_mark_node
4239 /* This can happen after weird syntax errors
4240 or if an enum type is defined among the parms. */
4241 || TREE_CODE (parm) != PARM_DECL
4242 || passed_type == NULL)
4244 DECL_INCOMING_RTL (parm) = DECL_RTL (parm)
4245 = gen_rtx_MEM (BLKmode, const0_rtx);
4246 TREE_USED (parm) = 1;
4250 /* For varargs.h function, save info about regs and stack space
4251 used by the individual args, not including the va_alist arg. */
4252 if (hide_last_arg && last_named)
4253 current_function_args_info = args_so_far;
4255 /* Find mode of arg as it is passed, and mode of arg
4256 as it should be during execution of this function. */
4257 passed_mode = TYPE_MODE (passed_type);
4258 nominal_mode = TYPE_MODE (nominal_type);
4260 /* If the parm's mode is VOID, its value doesn't matter,
4261 and avoid the usual things like emit_move_insn that could crash. */
4262 if (nominal_mode == VOIDmode)
4264 DECL_INCOMING_RTL (parm) = DECL_RTL (parm) = const0_rtx;
4268 /* If the parm is to be passed as a transparent union, use the
4269 type of the first field for the tests below. We have already
4270 verified that the modes are the same. */
4271 if (DECL_TRANSPARENT_UNION (parm)
4272 || (TREE_CODE (passed_type) == UNION_TYPE
4273 && TYPE_TRANSPARENT_UNION (passed_type)))
4274 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4276 /* See if this arg was passed by invisible reference. It is if
4277 it is an object whose size depends on the contents of the
4278 object itself or if the machine requires these objects be passed
4281 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
4282 && contains_placeholder_p (TYPE_SIZE (passed_type)))
4283 || TREE_ADDRESSABLE (passed_type)
4284 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4285 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4286 passed_type, named_arg)
4290 passed_type = nominal_type = build_pointer_type (passed_type);
4292 passed_mode = nominal_mode = Pmode;
4295 promoted_mode = passed_mode;
4297 #ifdef PROMOTE_FUNCTION_ARGS
4298 /* Compute the mode in which the arg is actually extended to. */
4299 unsignedp = TREE_UNSIGNED (passed_type);
4300 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4303 /* Let machine desc say which reg (if any) the parm arrives in.
4304 0 means it arrives on the stack. */
4305 #ifdef FUNCTION_INCOMING_ARG
4306 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4307 passed_type, named_arg);
4309 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4310 passed_type, named_arg);
4313 if (entry_parm == 0)
4314 promoted_mode = passed_mode;
4316 #ifdef SETUP_INCOMING_VARARGS
4317 /* If this is the last named parameter, do any required setup for
4318 varargs or stdargs. We need to know about the case of this being an
4319 addressable type, in which case we skip the registers it
4320 would have arrived in.
4322 For stdargs, LAST_NAMED will be set for two parameters, the one that
4323 is actually the last named, and the dummy parameter. We only
4324 want to do this action once.
4326 Also, indicate when RTL generation is to be suppressed. */
4327 if (last_named && !varargs_setup)
4329 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
4330 current_function_pretend_args_size, 0);
4335 /* Determine parm's home in the stack,
4336 in case it arrives in the stack or we should pretend it did.
4338 Compute the stack position and rtx where the argument arrives
4341 There is one complexity here: If this was a parameter that would
4342 have been passed in registers, but wasn't only because it is
4343 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4344 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4345 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4346 0 as it was the previous time. */
4348 pretend_named = named_arg || PRETEND_OUTGOING_VARARGS_NAMED;
4349 locate_and_pad_parm (promoted_mode, passed_type,
4350 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4353 #ifdef FUNCTION_INCOMING_ARG
4354 FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4356 pretend_named) != 0,
4358 FUNCTION_ARG (args_so_far, promoted_mode,
4360 pretend_named) != 0,
4363 fndecl, &stack_args_size, &stack_offset, &arg_size,
4367 rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
4369 if (offset_rtx == const0_rtx)
4370 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4372 stack_parm = gen_rtx_MEM (promoted_mode,
4373 gen_rtx_PLUS (Pmode,
4374 internal_arg_pointer,
4377 set_mem_attributes (stack_parm, parm, 1);
4380 /* If this parameter was passed both in registers and in the stack,
4381 use the copy on the stack. */
4382 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4385 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4386 /* If this parm was passed part in regs and part in memory,
4387 pretend it arrived entirely in memory
4388 by pushing the register-part onto the stack.
4390 In the special case of a DImode or DFmode that is split,
4391 we could put it together in a pseudoreg directly,
4392 but for now that's not worth bothering with. */
4396 int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4397 passed_type, named_arg);
4401 current_function_pretend_args_size
4402 = (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
4403 / (PARM_BOUNDARY / BITS_PER_UNIT)
4404 * (PARM_BOUNDARY / BITS_PER_UNIT));
4406 /* Handle calls that pass values in multiple non-contiguous
4407 locations. The Irix 6 ABI has examples of this. */
4408 if (GET_CODE (entry_parm) == PARALLEL)
4409 emit_group_store (validize_mem (stack_parm), entry_parm,
4410 int_size_in_bytes (TREE_TYPE (parm)),
4411 TYPE_ALIGN (TREE_TYPE (parm)));
4414 move_block_from_reg (REGNO (entry_parm),
4415 validize_mem (stack_parm), nregs,
4416 int_size_in_bytes (TREE_TYPE (parm)));
4418 entry_parm = stack_parm;
4423 /* If we didn't decide this parm came in a register,
4424 by default it came on the stack. */
4425 if (entry_parm == 0)
4426 entry_parm = stack_parm;
4428 /* Record permanently how this parm was passed. */
4429 DECL_INCOMING_RTL (parm) = entry_parm;
4431 /* If there is actually space on the stack for this parm,
4432 count it in stack_args_size; otherwise set stack_parm to 0
4433 to indicate there is no preallocated stack slot for the parm. */
4435 if (entry_parm == stack_parm
4436 || (GET_CODE (entry_parm) == PARALLEL
4437 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4438 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4439 /* On some machines, even if a parm value arrives in a register
4440 there is still an (uninitialized) stack slot allocated for it.
4442 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4443 whether this parameter already has a stack slot allocated,
4444 because an arg block exists only if current_function_args_size
4445 is larger than some threshold, and we haven't calculated that
4446 yet. So, for now, we just assume that stack slots never exist
4448 || REG_PARM_STACK_SPACE (fndecl) > 0
4452 stack_args_size.constant += arg_size.constant;
4454 ADD_PARM_SIZE (stack_args_size, arg_size.var);
4457 /* No stack slot was pushed for this parm. */
4460 /* Update info on where next arg arrives in registers. */
4462 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4463 passed_type, named_arg);
4465 /* If we can't trust the parm stack slot to be aligned enough
4466 for its ultimate type, don't use that slot after entry.
4467 We'll make another stack slot, if we need one. */
4469 unsigned int thisparm_boundary
4470 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4472 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4476 /* If parm was passed in memory, and we need to convert it on entry,
4477 don't store it back in that same slot. */
4479 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4482 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4483 in the mode in which it arrives.
4484 STACK_PARM is an RTX for a stack slot where the parameter can live
4485 during the function (in case we want to put it there).
4486 STACK_PARM is 0 if no stack slot was pushed for it.
4488 Now output code if necessary to convert ENTRY_PARM to
4489 the type in which this function declares it,
4490 and store that result in an appropriate place,
4491 which may be a pseudo reg, may be STACK_PARM,
4492 or may be a local stack slot if STACK_PARM is 0.
4494 Set DECL_RTL to that place. */
4496 if (nominal_mode == BLKmode || GET_CODE (entry_parm) == PARALLEL)
4498 /* If a BLKmode arrives in registers, copy it to a stack slot.
4499 Handle calls that pass values in multiple non-contiguous
4500 locations. The Irix 6 ABI has examples of this. */
4501 if (GET_CODE (entry_parm) == REG
4502 || GET_CODE (entry_parm) == PARALLEL)
4505 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
4508 /* Note that we will be storing an integral number of words.
4509 So we have to be careful to ensure that we allocate an
4510 integral number of words. We do this below in the
4511 assign_stack_local if space was not allocated in the argument
4512 list. If it was, this will not work if PARM_BOUNDARY is not
4513 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4514 if it becomes a problem. */
4516 if (stack_parm == 0)
4519 = assign_stack_local (GET_MODE (entry_parm),
4521 set_mem_attributes (stack_parm, parm, 1);
4524 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4527 /* Handle calls that pass values in multiple non-contiguous
4528 locations. The Irix 6 ABI has examples of this. */
4529 if (GET_CODE (entry_parm) == PARALLEL)
4530 emit_group_store (validize_mem (stack_parm), entry_parm,
4531 int_size_in_bytes (TREE_TYPE (parm)),
4532 TYPE_ALIGN (TREE_TYPE (parm)));
4534 move_block_from_reg (REGNO (entry_parm),
4535 validize_mem (stack_parm),
4536 size_stored / UNITS_PER_WORD,
4537 int_size_in_bytes (TREE_TYPE (parm)));
4539 DECL_RTL (parm) = stack_parm;
4541 else if (! ((! optimize
4542 && ! DECL_REGISTER (parm)
4543 && ! DECL_INLINE (fndecl))
4544 /* layout_decl may set this. */
4545 || TREE_ADDRESSABLE (parm)
4546 || TREE_SIDE_EFFECTS (parm)
4547 /* If -ffloat-store specified, don't put explicit
4548 float variables into registers. */
4549 || (flag_float_store
4550 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4551 /* Always assign pseudo to structure return or item passed
4552 by invisible reference. */
4553 || passed_pointer || parm == function_result_decl)
4555 /* Store the parm in a pseudoregister during the function, but we
4556 may need to do it in a wider mode. */
4558 register rtx parmreg;
4559 unsigned int regno, regnoi = 0, regnor = 0;
4561 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4563 promoted_nominal_mode
4564 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4566 parmreg = gen_reg_rtx (promoted_nominal_mode);
4567 mark_user_reg (parmreg);
4569 /* If this was an item that we received a pointer to, set DECL_RTL
4574 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)), parmreg);
4575 set_mem_attributes (DECL_RTL (parm), parm, 1);
4578 DECL_RTL (parm) = parmreg;
4580 /* Copy the value into the register. */
4581 if (nominal_mode != passed_mode
4582 || promoted_nominal_mode != promoted_mode)
4585 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4586 mode, by the caller. We now have to convert it to
4587 NOMINAL_MODE, if different. However, PARMREG may be in
4588 a different mode than NOMINAL_MODE if it is being stored
4591 If ENTRY_PARM is a hard register, it might be in a register
4592 not valid for operating in its mode (e.g., an odd-numbered
4593 register for a DFmode). In that case, moves are the only
4594 thing valid, so we can't do a convert from there. This
4595 occurs when the calling sequence allow such misaligned
4598 In addition, the conversion may involve a call, which could
4599 clobber parameters which haven't been copied to pseudo
4600 registers yet. Therefore, we must first copy the parm to
4601 a pseudo reg here, and save the conversion until after all
4602 parameters have been moved. */
4604 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4606 emit_move_insn (tempreg, validize_mem (entry_parm));
4608 push_to_sequence (conversion_insns);
4609 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4611 /* TREE_USED gets set erroneously during expand_assignment. */
4612 save_tree_used = TREE_USED (parm);
4613 expand_assignment (parm,
4614 make_tree (nominal_type, tempreg), 0, 0);
4615 TREE_USED (parm) = save_tree_used;
4616 conversion_insns = get_insns ();
4621 emit_move_insn (parmreg, validize_mem (entry_parm));
4623 /* If we were passed a pointer but the actual value
4624 can safely live in a register, put it in one. */
4625 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4627 && ! DECL_REGISTER (parm)
4628 && ! DECL_INLINE (fndecl))
4629 /* layout_decl may set this. */
4630 || TREE_ADDRESSABLE (parm)
4631 || TREE_SIDE_EFFECTS (parm)
4632 /* If -ffloat-store specified, don't put explicit
4633 float variables into registers. */
4634 || (flag_float_store
4635 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE)))
4637 /* We can't use nominal_mode, because it will have been set to
4638 Pmode above. We must use the actual mode of the parm. */
4639 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4640 mark_user_reg (parmreg);
4641 emit_move_insn (parmreg, DECL_RTL (parm));
4642 DECL_RTL (parm) = parmreg;
4643 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4647 #ifdef FUNCTION_ARG_CALLEE_COPIES
4648 /* If we are passed an arg by reference and it is our responsibility
4649 to make a copy, do it now.
4650 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4651 original argument, so we must recreate them in the call to
4652 FUNCTION_ARG_CALLEE_COPIES. */
4653 /* ??? Later add code to handle the case that if the argument isn't
4654 modified, don't do the copy. */
4656 else if (passed_pointer
4657 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4658 TYPE_MODE (DECL_ARG_TYPE (parm)),
4659 DECL_ARG_TYPE (parm),
4661 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4664 tree type = DECL_ARG_TYPE (parm);
4666 /* This sequence may involve a library call perhaps clobbering
4667 registers that haven't been copied to pseudos yet. */
4669 push_to_sequence (conversion_insns);
4671 if (!COMPLETE_TYPE_P (type)
4672 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4673 /* This is a variable sized object. */
4674 copy = gen_rtx_MEM (BLKmode,
4675 allocate_dynamic_stack_space
4676 (expr_size (parm), NULL_RTX,
4677 TYPE_ALIGN (type)));
4679 copy = assign_stack_temp (TYPE_MODE (type),
4680 int_size_in_bytes (type), 1);
4681 set_mem_attributes (copy, parm, 1);
4683 store_expr (parm, copy, 0);
4684 emit_move_insn (parmreg, XEXP (copy, 0));
4685 if (current_function_check_memory_usage)
4686 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
4687 XEXP (copy, 0), Pmode,
4688 GEN_INT (int_size_in_bytes (type)),
4689 TYPE_MODE (sizetype),
4690 GEN_INT (MEMORY_USE_RW),
4691 TYPE_MODE (integer_type_node));
4692 conversion_insns = get_insns ();
4696 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4698 /* In any case, record the parm's desired stack location
4699 in case we later discover it must live in the stack.
4701 If it is a COMPLEX value, store the stack location for both
4704 if (GET_CODE (parmreg) == CONCAT)
4705 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4707 regno = REGNO (parmreg);
4709 if (regno >= max_parm_reg)
4712 int old_max_parm_reg = max_parm_reg;
4714 /* It's slow to expand this one register at a time,
4715 but it's also rare and we need max_parm_reg to be
4716 precisely correct. */
4717 max_parm_reg = regno + 1;
4718 new = (rtx *) xrealloc (parm_reg_stack_loc,
4719 max_parm_reg * sizeof (rtx));
4720 bzero ((char *) (new + old_max_parm_reg),
4721 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4722 parm_reg_stack_loc = new;
4725 if (GET_CODE (parmreg) == CONCAT)
4727 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
4729 regnor = REGNO (gen_realpart (submode, parmreg));
4730 regnoi = REGNO (gen_imagpart (submode, parmreg));
4732 if (stack_parm != 0)
4734 parm_reg_stack_loc[regnor]
4735 = gen_realpart (submode, stack_parm);
4736 parm_reg_stack_loc[regnoi]
4737 = gen_imagpart (submode, stack_parm);
4741 parm_reg_stack_loc[regnor] = 0;
4742 parm_reg_stack_loc[regnoi] = 0;
4746 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
4748 /* Mark the register as eliminable if we did no conversion
4749 and it was copied from memory at a fixed offset,
4750 and the arg pointer was not copied to a pseudo-reg.
4751 If the arg pointer is a pseudo reg or the offset formed
4752 an invalid address, such memory-equivalences
4753 as we make here would screw up life analysis for it. */
4754 if (nominal_mode == passed_mode
4757 && GET_CODE (stack_parm) == MEM
4758 && stack_offset.var == 0
4759 && reg_mentioned_p (virtual_incoming_args_rtx,
4760 XEXP (stack_parm, 0)))
4762 rtx linsn = get_last_insn ();
4765 /* Mark complex types separately. */
4766 if (GET_CODE (parmreg) == CONCAT)
4767 /* Scan backwards for the set of the real and
4769 for (sinsn = linsn; sinsn != 0;
4770 sinsn = prev_nonnote_insn (sinsn))
4772 set = single_set (sinsn);
4774 && SET_DEST (set) == regno_reg_rtx [regnoi])
4776 = gen_rtx_EXPR_LIST (REG_EQUIV,
4777 parm_reg_stack_loc[regnoi],
4780 && SET_DEST (set) == regno_reg_rtx [regnor])
4782 = gen_rtx_EXPR_LIST (REG_EQUIV,
4783 parm_reg_stack_loc[regnor],
4786 else if ((set = single_set (linsn)) != 0
4787 && SET_DEST (set) == parmreg)
4789 = gen_rtx_EXPR_LIST (REG_EQUIV,
4790 stack_parm, REG_NOTES (linsn));
4793 /* For pointer data type, suggest pointer register. */
4794 if (POINTER_TYPE_P (TREE_TYPE (parm)))
4795 mark_reg_pointer (parmreg,
4796 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
4801 /* Value must be stored in the stack slot STACK_PARM
4802 during function execution. */
4804 if (promoted_mode != nominal_mode)
4806 /* Conversion is required. */
4807 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4809 emit_move_insn (tempreg, validize_mem (entry_parm));
4811 push_to_sequence (conversion_insns);
4812 entry_parm = convert_to_mode (nominal_mode, tempreg,
4813 TREE_UNSIGNED (TREE_TYPE (parm)));
4816 /* ??? This may need a big-endian conversion on sparc64. */
4817 stack_parm = change_address (stack_parm, nominal_mode,
4820 conversion_insns = get_insns ();
4825 if (entry_parm != stack_parm)
4827 if (stack_parm == 0)
4830 = assign_stack_local (GET_MODE (entry_parm),
4831 GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
4832 set_mem_attributes (stack_parm, parm, 1);
4835 if (promoted_mode != nominal_mode)
4837 push_to_sequence (conversion_insns);
4838 emit_move_insn (validize_mem (stack_parm),
4839 validize_mem (entry_parm));
4840 conversion_insns = get_insns ();
4844 emit_move_insn (validize_mem (stack_parm),
4845 validize_mem (entry_parm));
4847 if (current_function_check_memory_usage)
4849 push_to_sequence (conversion_insns);
4850 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
4851 XEXP (stack_parm, 0), Pmode,
4852 GEN_INT (GET_MODE_SIZE (GET_MODE
4854 TYPE_MODE (sizetype),
4855 GEN_INT (MEMORY_USE_RW),
4856 TYPE_MODE (integer_type_node));
4858 conversion_insns = get_insns ();
4861 DECL_RTL (parm) = stack_parm;
4864 /* If this "parameter" was the place where we are receiving the
4865 function's incoming structure pointer, set up the result. */
4866 if (parm == function_result_decl)
4868 tree result = DECL_RESULT (fndecl);
4871 = gen_rtx_MEM (DECL_MODE (result), DECL_RTL (parm));
4873 set_mem_attributes (DECL_RTL (result), result, 1);
4877 /* Output all parameter conversion instructions (possibly including calls)
4878 now that all parameters have been copied out of hard registers. */
4879 emit_insns (conversion_insns);
4881 last_parm_insn = get_last_insn ();
4883 current_function_args_size = stack_args_size.constant;
4885 /* Adjust function incoming argument size for alignment and
4888 #ifdef REG_PARM_STACK_SPACE
4889 #ifndef MAYBE_REG_PARM_STACK_SPACE
4890 current_function_args_size = MAX (current_function_args_size,
4891 REG_PARM_STACK_SPACE (fndecl));
4895 #ifdef STACK_BOUNDARY
4896 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
4898 current_function_args_size
4899 = ((current_function_args_size + STACK_BYTES - 1)
4900 / STACK_BYTES) * STACK_BYTES;
4903 #ifdef ARGS_GROW_DOWNWARD
4904 current_function_arg_offset_rtx
4905 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
4906 : expand_expr (size_diffop (stack_args_size.var,
4907 size_int (-stack_args_size.constant)),
4908 NULL_RTX, VOIDmode, EXPAND_MEMORY_USE_BAD));
4910 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
4913 /* See how many bytes, if any, of its args a function should try to pop
4916 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
4917 current_function_args_size);
4919 /* For stdarg.h function, save info about
4920 regs and stack space used by the named args. */
4923 current_function_args_info = args_so_far;
4925 /* Set the rtx used for the function return value. Put this in its
4926 own variable so any optimizers that need this information don't have
4927 to include tree.h. Do this here so it gets done when an inlined
4928 function gets output. */
4930 current_function_return_rtx = DECL_RTL (DECL_RESULT (fndecl));
4933 /* Indicate whether REGNO is an incoming argument to the current function
4934 that was promoted to a wider mode. If so, return the RTX for the
4935 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
4936 that REGNO is promoted from and whether the promotion was signed or
4939 #ifdef PROMOTE_FUNCTION_ARGS
4942 promoted_input_arg (regno, pmode, punsignedp)
4944 enum machine_mode *pmode;
4949 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
4950 arg = TREE_CHAIN (arg))
4951 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
4952 && REGNO (DECL_INCOMING_RTL (arg)) == regno
4953 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
4955 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
4956 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
4958 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
4959 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
4960 && mode != DECL_MODE (arg))
4962 *pmode = DECL_MODE (arg);
4963 *punsignedp = unsignedp;
4964 return DECL_INCOMING_RTL (arg);
4973 /* Compute the size and offset from the start of the stacked arguments for a
4974 parm passed in mode PASSED_MODE and with type TYPE.
4976 INITIAL_OFFSET_PTR points to the current offset into the stacked
4979 The starting offset and size for this parm are returned in *OFFSET_PTR
4980 and *ARG_SIZE_PTR, respectively.
4982 IN_REGS is non-zero if the argument will be passed in registers. It will
4983 never be set if REG_PARM_STACK_SPACE is not defined.
4985 FNDECL is the function in which the argument was defined.
4987 There are two types of rounding that are done. The first, controlled by
4988 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
4989 list to be aligned to the specific boundary (in bits). This rounding
4990 affects the initial and starting offsets, but not the argument size.
4992 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
4993 optionally rounds the size of the parm to PARM_BOUNDARY. The
4994 initial offset is not affected by this rounding, while the size always
4995 is and the starting offset may be. */
4997 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
4998 initial_offset_ptr is positive because locate_and_pad_parm's
4999 callers pass in the total size of args so far as
5000 initial_offset_ptr. arg_size_ptr is always positive.*/
5003 locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
5004 initial_offset_ptr, offset_ptr, arg_size_ptr,
5006 enum machine_mode passed_mode;
5008 int in_regs ATTRIBUTE_UNUSED;
5009 tree fndecl ATTRIBUTE_UNUSED;
5010 struct args_size *initial_offset_ptr;
5011 struct args_size *offset_ptr;
5012 struct args_size *arg_size_ptr;
5013 struct args_size *alignment_pad;
5017 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5018 enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5019 int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5021 #ifdef REG_PARM_STACK_SPACE
5022 /* If we have found a stack parm before we reach the end of the
5023 area reserved for registers, skip that area. */
5026 int reg_parm_stack_space = 0;
5028 #ifdef MAYBE_REG_PARM_STACK_SPACE
5029 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
5031 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5033 if (reg_parm_stack_space > 0)
5035 if (initial_offset_ptr->var)
5037 initial_offset_ptr->var
5038 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5039 ssize_int (reg_parm_stack_space));
5040 initial_offset_ptr->constant = 0;
5042 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5043 initial_offset_ptr->constant = reg_parm_stack_space;
5046 #endif /* REG_PARM_STACK_SPACE */
5048 arg_size_ptr->var = 0;
5049 arg_size_ptr->constant = 0;
5051 #ifdef ARGS_GROW_DOWNWARD
5052 if (initial_offset_ptr->var)
5054 offset_ptr->constant = 0;
5055 offset_ptr->var = size_binop (MINUS_EXPR, ssize_int (0),
5056 initial_offset_ptr->var);
5060 offset_ptr->constant = -initial_offset_ptr->constant;
5061 offset_ptr->var = 0;
5063 if (where_pad != none
5064 && (TREE_CODE (sizetree) != INTEGER_CST
5065 || ((TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)))
5066 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5067 SUB_PARM_SIZE (*offset_ptr, sizetree);
5068 if (where_pad != downward)
5069 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad);
5070 if (initial_offset_ptr->var)
5071 arg_size_ptr->var = size_binop (MINUS_EXPR,
5072 size_binop (MINUS_EXPR,
5074 initial_offset_ptr->var),
5078 arg_size_ptr->constant = (-initial_offset_ptr->constant
5079 - offset_ptr->constant);
5081 #else /* !ARGS_GROW_DOWNWARD */
5082 pad_to_arg_alignment (initial_offset_ptr, boundary, alignment_pad);
5083 *offset_ptr = *initial_offset_ptr;
5085 #ifdef PUSH_ROUNDING
5086 if (passed_mode != BLKmode)
5087 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5090 /* Pad_below needs the pre-rounded size to know how much to pad below
5091 so this must be done before rounding up. */
5092 if (where_pad == downward
5093 /* However, BLKmode args passed in regs have their padding done elsewhere.
5094 The stack slot must be able to hold the entire register. */
5095 && !(in_regs && passed_mode == BLKmode))
5096 pad_below (offset_ptr, passed_mode, sizetree);
5098 if (where_pad != none
5099 && (TREE_CODE (sizetree) != INTEGER_CST
5100 || ((TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)))
5101 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5103 ADD_PARM_SIZE (*arg_size_ptr, sizetree);
5104 #endif /* ARGS_GROW_DOWNWARD */
5107 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5108 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5111 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad)
5112 struct args_size *offset_ptr;
5114 struct args_size *alignment_pad;
5116 tree save_var = NULL_TREE;
5117 HOST_WIDE_INT save_constant = 0;
5119 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5121 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5123 save_var = offset_ptr->var;
5124 save_constant = offset_ptr->constant;
5127 alignment_pad->var = NULL_TREE;
5128 alignment_pad->constant = 0;
5130 if (boundary > BITS_PER_UNIT)
5132 if (offset_ptr->var)
5135 #ifdef ARGS_GROW_DOWNWARD
5140 (ARGS_SIZE_TREE (*offset_ptr),
5141 boundary / BITS_PER_UNIT);
5142 offset_ptr->constant = 0; /*?*/
5143 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5144 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5149 offset_ptr->constant =
5150 #ifdef ARGS_GROW_DOWNWARD
5151 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
5153 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
5155 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5156 alignment_pad->constant = offset_ptr->constant - save_constant;
5161 #ifndef ARGS_GROW_DOWNWARD
5163 pad_below (offset_ptr, passed_mode, sizetree)
5164 struct args_size *offset_ptr;
5165 enum machine_mode passed_mode;
5168 if (passed_mode != BLKmode)
5170 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5171 offset_ptr->constant
5172 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5173 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5174 - GET_MODE_SIZE (passed_mode));
5178 if (TREE_CODE (sizetree) != INTEGER_CST
5179 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5181 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5182 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5184 ADD_PARM_SIZE (*offset_ptr, s2);
5185 SUB_PARM_SIZE (*offset_ptr, sizetree);
5191 /* Walk the tree of blocks describing the binding levels within a function
5192 and warn about uninitialized variables.
5193 This is done after calling flow_analysis and before global_alloc
5194 clobbers the pseudo-regs to hard regs. */
5197 uninitialized_vars_warning (block)
5200 register tree decl, sub;
5201 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5203 if (warn_uninitialized
5204 && TREE_CODE (decl) == VAR_DECL
5205 /* These warnings are unreliable for and aggregates
5206 because assigning the fields one by one can fail to convince
5207 flow.c that the entire aggregate was initialized.
5208 Unions are troublesome because members may be shorter. */
5209 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5210 && DECL_RTL (decl) != 0
5211 && GET_CODE (DECL_RTL (decl)) == REG
5212 /* Global optimizations can make it difficult to determine if a
5213 particular variable has been initialized. However, a VAR_DECL
5214 with a nonzero DECL_INITIAL had an initializer, so do not
5215 claim it is potentially uninitialized.
5217 We do not care about the actual value in DECL_INITIAL, so we do
5218 not worry that it may be a dangling pointer. */
5219 && DECL_INITIAL (decl) == NULL_TREE
5220 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5221 warning_with_decl (decl,
5222 "`%s' might be used uninitialized in this function");
5224 && TREE_CODE (decl) == VAR_DECL
5225 && DECL_RTL (decl) != 0
5226 && GET_CODE (DECL_RTL (decl)) == REG
5227 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5228 warning_with_decl (decl,
5229 "variable `%s' might be clobbered by `longjmp' or `vfork'");
5231 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5232 uninitialized_vars_warning (sub);
5235 /* Do the appropriate part of uninitialized_vars_warning
5236 but for arguments instead of local variables. */
5239 setjmp_args_warning ()
5242 for (decl = DECL_ARGUMENTS (current_function_decl);
5243 decl; decl = TREE_CHAIN (decl))
5244 if (DECL_RTL (decl) != 0
5245 && GET_CODE (DECL_RTL (decl)) == REG
5246 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5247 warning_with_decl (decl,
5248 "argument `%s' might be clobbered by `longjmp' or `vfork'");
5251 /* If this function call setjmp, put all vars into the stack
5252 unless they were declared `register'. */
5255 setjmp_protect (block)
5258 register tree decl, sub;
5259 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5260 if ((TREE_CODE (decl) == VAR_DECL
5261 || TREE_CODE (decl) == PARM_DECL)
5262 && DECL_RTL (decl) != 0
5263 && (GET_CODE (DECL_RTL (decl)) == REG
5264 || (GET_CODE (DECL_RTL (decl)) == MEM
5265 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5266 /* If this variable came from an inline function, it must be
5267 that its life doesn't overlap the setjmp. If there was a
5268 setjmp in the function, it would already be in memory. We
5269 must exclude such variable because their DECL_RTL might be
5270 set to strange things such as virtual_stack_vars_rtx. */
5271 && ! DECL_FROM_INLINE (decl)
5273 #ifdef NON_SAVING_SETJMP
5274 /* If longjmp doesn't restore the registers,
5275 don't put anything in them. */
5279 ! DECL_REGISTER (decl)))
5280 put_var_into_stack (decl);
5281 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5282 setjmp_protect (sub);
5285 /* Like the previous function, but for args instead of local variables. */
5288 setjmp_protect_args ()
5291 for (decl = DECL_ARGUMENTS (current_function_decl);
5292 decl; decl = TREE_CHAIN (decl))
5293 if ((TREE_CODE (decl) == VAR_DECL
5294 || TREE_CODE (decl) == PARM_DECL)
5295 && DECL_RTL (decl) != 0
5296 && (GET_CODE (DECL_RTL (decl)) == REG
5297 || (GET_CODE (DECL_RTL (decl)) == MEM
5298 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5300 /* If longjmp doesn't restore the registers,
5301 don't put anything in them. */
5302 #ifdef NON_SAVING_SETJMP
5306 ! DECL_REGISTER (decl)))
5307 put_var_into_stack (decl);
5310 /* Return the context-pointer register corresponding to DECL,
5311 or 0 if it does not need one. */
5314 lookup_static_chain (decl)
5317 tree context = decl_function_context (decl);
5321 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5324 /* We treat inline_function_decl as an alias for the current function
5325 because that is the inline function whose vars, types, etc.
5326 are being merged into the current function.
5327 See expand_inline_function. */
5328 if (context == current_function_decl || context == inline_function_decl)
5329 return virtual_stack_vars_rtx;
5331 for (link = context_display; link; link = TREE_CHAIN (link))
5332 if (TREE_PURPOSE (link) == context)
5333 return RTL_EXPR_RTL (TREE_VALUE (link));
5338 /* Convert a stack slot address ADDR for variable VAR
5339 (from a containing function)
5340 into an address valid in this function (using a static chain). */
5343 fix_lexical_addr (addr, var)
5348 HOST_WIDE_INT displacement;
5349 tree context = decl_function_context (var);
5350 struct function *fp;
5353 /* If this is the present function, we need not do anything. */
5354 if (context == current_function_decl || context == inline_function_decl)
5357 for (fp = outer_function_chain; fp; fp = fp->next)
5358 if (fp->decl == context)
5364 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5365 addr = XEXP (XEXP (addr, 0), 0);
5367 /* Decode given address as base reg plus displacement. */
5368 if (GET_CODE (addr) == REG)
5369 basereg = addr, displacement = 0;
5370 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5371 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5375 /* We accept vars reached via the containing function's
5376 incoming arg pointer and via its stack variables pointer. */
5377 if (basereg == fp->internal_arg_pointer)
5379 /* If reached via arg pointer, get the arg pointer value
5380 out of that function's stack frame.
5382 There are two cases: If a separate ap is needed, allocate a
5383 slot in the outer function for it and dereference it that way.
5384 This is correct even if the real ap is actually a pseudo.
5385 Otherwise, just adjust the offset from the frame pointer to
5388 #ifdef NEED_SEPARATE_AP
5391 if (fp->x_arg_pointer_save_area == 0)
5392 fp->x_arg_pointer_save_area
5393 = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, fp);
5395 addr = fix_lexical_addr (XEXP (fp->x_arg_pointer_save_area, 0), var);
5396 addr = memory_address (Pmode, addr);
5398 base = gen_rtx_MEM (Pmode, addr);
5399 MEM_ALIAS_SET (base) = get_frame_alias_set ();
5400 base = copy_to_reg (base);
5402 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5403 base = lookup_static_chain (var);
5407 else if (basereg == virtual_stack_vars_rtx)
5409 /* This is the same code as lookup_static_chain, duplicated here to
5410 avoid an extra call to decl_function_context. */
5413 for (link = context_display; link; link = TREE_CHAIN (link))
5414 if (TREE_PURPOSE (link) == context)
5416 base = RTL_EXPR_RTL (TREE_VALUE (link));
5424 /* Use same offset, relative to appropriate static chain or argument
5426 return plus_constant (base, displacement);
5429 /* Return the address of the trampoline for entering nested fn FUNCTION.
5430 If necessary, allocate a trampoline (in the stack frame)
5431 and emit rtl to initialize its contents (at entry to this function). */
5434 trampoline_address (function)
5440 struct function *fp;
5443 /* Find an existing trampoline and return it. */
5444 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5445 if (TREE_PURPOSE (link) == function)
5447 round_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5449 for (fp = outer_function_chain; fp; fp = fp->next)
5450 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5451 if (TREE_PURPOSE (link) == function)
5453 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5455 return round_trampoline_addr (tramp);
5458 /* None exists; we must make one. */
5460 /* Find the `struct function' for the function containing FUNCTION. */
5462 fn_context = decl_function_context (function);
5463 if (fn_context != current_function_decl
5464 && fn_context != inline_function_decl)
5465 for (fp = outer_function_chain; fp; fp = fp->next)
5466 if (fp->decl == fn_context)
5469 /* Allocate run-time space for this trampoline
5470 (usually in the defining function's stack frame). */
5471 #ifdef ALLOCATE_TRAMPOLINE
5472 tramp = ALLOCATE_TRAMPOLINE (fp);
5474 /* If rounding needed, allocate extra space
5475 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5476 #ifdef TRAMPOLINE_ALIGNMENT
5477 #define TRAMPOLINE_REAL_SIZE \
5478 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5480 #define TRAMPOLINE_REAL_SIZE (TRAMPOLINE_SIZE)
5482 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5486 /* Record the trampoline for reuse and note it for later initialization
5487 by expand_function_end. */
5490 push_obstacks (fp->function_maybepermanent_obstack,
5491 fp->function_maybepermanent_obstack);
5492 rtlexp = make_node (RTL_EXPR);
5493 RTL_EXPR_RTL (rtlexp) = tramp;
5494 fp->x_trampoline_list = tree_cons (function, rtlexp,
5495 fp->x_trampoline_list);
5500 /* Make the RTL_EXPR node temporary, not momentary, so that the
5501 trampoline_list doesn't become garbage. */
5502 int momentary = suspend_momentary ();
5503 rtlexp = make_node (RTL_EXPR);
5504 resume_momentary (momentary);
5506 RTL_EXPR_RTL (rtlexp) = tramp;
5507 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5510 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5511 return round_trampoline_addr (tramp);
5514 /* Given a trampoline address,
5515 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5518 round_trampoline_addr (tramp)
5521 #ifdef TRAMPOLINE_ALIGNMENT
5522 /* Round address up to desired boundary. */
5523 rtx temp = gen_reg_rtx (Pmode);
5524 temp = expand_binop (Pmode, add_optab, tramp,
5525 GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1),
5526 temp, 0, OPTAB_LIB_WIDEN);
5527 tramp = expand_binop (Pmode, and_optab, temp,
5528 GEN_INT (-TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT),
5529 temp, 0, OPTAB_LIB_WIDEN);
5534 /* Put all this function's BLOCK nodes including those that are chained
5535 onto the first block into a vector, and return it.
5536 Also store in each NOTE for the beginning or end of a block
5537 the index of that block in the vector.
5538 The arguments are BLOCK, the chain of top-level blocks of the function,
5539 and INSNS, the insn chain of the function. */
5545 tree *block_vector, *last_block_vector;
5547 tree block = DECL_INITIAL (current_function_decl);
5552 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5553 depth-first order. */
5554 block_vector = get_block_vector (block, &n_blocks);
5555 block_stack = (tree *) xmalloc (n_blocks * sizeof (tree));
5557 last_block_vector = identify_blocks_1 (get_insns (),
5559 block_vector + n_blocks,
5562 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5563 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5564 if (0 && last_block_vector != block_vector + n_blocks)
5567 free (block_vector);
5571 /* Subroutine of identify_blocks. Do the block substitution on the
5572 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
5574 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5575 BLOCK_VECTOR is incremented for each block seen. */
5578 identify_blocks_1 (insns, block_vector, end_block_vector, orig_block_stack)
5581 tree *end_block_vector;
5582 tree *orig_block_stack;
5585 tree *block_stack = orig_block_stack;
5587 for (insn = insns; insn; insn = NEXT_INSN (insn))
5589 if (GET_CODE (insn) == NOTE)
5591 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5595 /* If there are more block notes than BLOCKs, something
5597 if (block_vector == end_block_vector)
5600 b = *block_vector++;
5601 NOTE_BLOCK (insn) = b;
5604 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5606 /* If there are more NOTE_INSN_BLOCK_ENDs than
5607 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
5608 if (block_stack == orig_block_stack)
5611 NOTE_BLOCK (insn) = *--block_stack;
5614 else if (GET_CODE (insn) == CALL_INSN
5615 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5617 rtx cp = PATTERN (insn);
5619 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
5620 end_block_vector, block_stack);
5622 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
5623 end_block_vector, block_stack);
5625 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
5626 end_block_vector, block_stack);
5630 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
5631 something is badly wrong. */
5632 if (block_stack != orig_block_stack)
5635 return block_vector;
5638 /* Identify BLOCKs referenced by more than one
5639 NOTE_INSN_BLOCK_{BEG,END}, and create duplicate blocks. */
5644 tree block = DECL_INITIAL (current_function_decl);
5645 varray_type block_stack;
5647 if (block == NULL_TREE)
5650 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
5652 /* Prune the old trees away, so that they don't get in the way. */
5653 BLOCK_SUBBLOCKS (block) = NULL_TREE;
5654 BLOCK_CHAIN (block) = NULL_TREE;
5656 reorder_blocks_1 (get_insns (), block, &block_stack);
5658 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
5660 VARRAY_FREE (block_stack);
5663 /* Helper function for reorder_blocks. Process the insn chain beginning
5664 at INSNS. Recurse for CALL_PLACEHOLDER insns. */
5667 reorder_blocks_1 (insns, current_block, p_block_stack)
5670 varray_type *p_block_stack;
5674 for (insn = insns; insn; insn = NEXT_INSN (insn))
5676 if (GET_CODE (insn) == NOTE)
5678 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5680 tree block = NOTE_BLOCK (insn);
5681 /* If we have seen this block before, copy it. */
5682 if (TREE_ASM_WRITTEN (block))
5684 block = copy_node (block);
5685 NOTE_BLOCK (insn) = block;
5687 BLOCK_SUBBLOCKS (block) = 0;
5688 TREE_ASM_WRITTEN (block) = 1;
5689 BLOCK_SUPERCONTEXT (block) = current_block;
5690 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
5691 BLOCK_SUBBLOCKS (current_block) = block;
5692 current_block = block;
5693 VARRAY_PUSH_TREE (*p_block_stack, block);
5695 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5697 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
5698 VARRAY_POP (*p_block_stack);
5699 BLOCK_SUBBLOCKS (current_block)
5700 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5701 current_block = BLOCK_SUPERCONTEXT (current_block);
5704 else if (GET_CODE (insn) == CALL_INSN
5705 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5707 rtx cp = PATTERN (insn);
5708 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
5710 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
5712 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
5717 /* Reverse the order of elements in the chain T of blocks,
5718 and return the new head of the chain (old last element). */
5724 register tree prev = 0, decl, next;
5725 for (decl = t; decl; decl = next)
5727 next = BLOCK_CHAIN (decl);
5728 BLOCK_CHAIN (decl) = prev;
5734 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
5735 non-NULL, list them all into VECTOR, in a depth-first preorder
5736 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
5740 all_blocks (block, vector)
5748 TREE_ASM_WRITTEN (block) = 0;
5750 /* Record this block. */
5752 vector[n_blocks] = block;
5756 /* Record the subblocks, and their subblocks... */
5757 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
5758 vector ? vector + n_blocks : 0);
5759 block = BLOCK_CHAIN (block);
5765 /* Return a vector containing all the blocks rooted at BLOCK. The
5766 number of elements in the vector is stored in N_BLOCKS_P. The
5767 vector is dynamically allocated; it is the caller's responsibility
5768 to call `free' on the pointer returned. */
5771 get_block_vector (block, n_blocks_p)
5777 *n_blocks_p = all_blocks (block, NULL);
5778 block_vector = (tree *) xmalloc (*n_blocks_p * sizeof (tree));
5779 all_blocks (block, block_vector);
5781 return block_vector;
5784 static int next_block_index = 2;
5786 /* Set BLOCK_NUMBER for all the blocks in FN. */
5796 /* For SDB and XCOFF debugging output, we start numbering the blocks
5797 from 1 within each function, rather than keeping a running
5799 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
5800 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
5801 next_block_index = 1;
5804 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
5806 /* The top-level BLOCK isn't numbered at all. */
5807 for (i = 1; i < n_blocks; ++i)
5808 /* We number the blocks from two. */
5809 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
5811 free (block_vector);
5816 /* Allocate a function structure and reset its contents to the defaults. */
5818 prepare_function_start ()
5820 cfun = (struct function *) xcalloc (1, sizeof (struct function));
5822 init_stmt_for_function ();
5823 init_eh_for_function ();
5825 cse_not_expected = ! optimize;
5827 /* Caller save not needed yet. */
5828 caller_save_needed = 0;
5830 /* No stack slots have been made yet. */
5831 stack_slot_list = 0;
5833 current_function_has_nonlocal_label = 0;
5834 current_function_has_nonlocal_goto = 0;
5836 /* There is no stack slot for handling nonlocal gotos. */
5837 nonlocal_goto_handler_slots = 0;
5838 nonlocal_goto_stack_level = 0;
5840 /* No labels have been declared for nonlocal use. */
5841 nonlocal_labels = 0;
5842 nonlocal_goto_handler_labels = 0;
5844 /* No function calls so far in this function. */
5845 function_call_count = 0;
5847 /* No parm regs have been allocated.
5848 (This is important for output_inline_function.) */
5849 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
5851 /* Initialize the RTL mechanism. */
5854 /* Initialize the queue of pending postincrement and postdecrements,
5855 and some other info in expr.c. */
5858 /* We haven't done register allocation yet. */
5861 init_varasm_status (cfun);
5863 /* Clear out data used for inlining. */
5864 cfun->inlinable = 0;
5865 cfun->original_decl_initial = 0;
5866 cfun->original_arg_vector = 0;
5868 #ifdef STACK_BOUNDARY
5869 cfun->stack_alignment_needed = STACK_BOUNDARY;
5870 cfun->preferred_stack_boundary = STACK_BOUNDARY;
5872 cfun->stack_alignment_needed = 0;
5873 cfun->preferred_stack_boundary = 0;
5876 /* Set if a call to setjmp is seen. */
5877 current_function_calls_setjmp = 0;
5879 /* Set if a call to longjmp is seen. */
5880 current_function_calls_longjmp = 0;
5882 current_function_calls_alloca = 0;
5883 current_function_contains_functions = 0;
5884 current_function_is_leaf = 0;
5885 current_function_nothrow = 0;
5886 current_function_sp_is_unchanging = 0;
5887 current_function_uses_only_leaf_regs = 0;
5888 current_function_has_computed_jump = 0;
5889 current_function_is_thunk = 0;
5891 current_function_returns_pcc_struct = 0;
5892 current_function_returns_struct = 0;
5893 current_function_epilogue_delay_list = 0;
5894 current_function_uses_const_pool = 0;
5895 current_function_uses_pic_offset_table = 0;
5896 current_function_cannot_inline = 0;
5898 /* We have not yet needed to make a label to jump to for tail-recursion. */
5899 tail_recursion_label = 0;
5901 /* We haven't had a need to make a save area for ap yet. */
5902 arg_pointer_save_area = 0;
5904 /* No stack slots allocated yet. */
5907 /* No SAVE_EXPRs in this function yet. */
5910 /* No RTL_EXPRs in this function yet. */
5913 /* Set up to allocate temporaries. */
5916 /* Indicate that we need to distinguish between the return value of the
5917 present function and the return value of a function being called. */
5918 rtx_equal_function_value_matters = 1;
5920 /* Indicate that we have not instantiated virtual registers yet. */
5921 virtuals_instantiated = 0;
5923 /* Indicate we have no need of a frame pointer yet. */
5924 frame_pointer_needed = 0;
5926 /* By default assume not varargs or stdarg. */
5927 current_function_varargs = 0;
5928 current_function_stdarg = 0;
5930 /* We haven't made any trampolines for this function yet. */
5931 trampoline_list = 0;
5933 init_pending_stack_adjust ();
5934 inhibit_defer_pop = 0;
5936 current_function_outgoing_args_size = 0;
5938 if (init_lang_status)
5939 (*init_lang_status) (cfun);
5940 if (init_machine_status)
5941 (*init_machine_status) (cfun);
5944 /* Initialize the rtl expansion mechanism so that we can do simple things
5945 like generate sequences. This is used to provide a context during global
5946 initialization of some passes. */
5948 init_dummy_function_start ()
5950 prepare_function_start ();
5953 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
5954 and initialize static variables for generating RTL for the statements
5958 init_function_start (subr, filename, line)
5960 const char *filename;
5963 prepare_function_start ();
5965 /* Remember this function for later. */
5966 cfun->next_global = all_functions;
5967 all_functions = cfun;
5969 current_function_name = (*decl_printable_name) (subr, 2);
5972 /* Nonzero if this is a nested function that uses a static chain. */
5974 current_function_needs_context
5975 = (decl_function_context (current_function_decl) != 0
5976 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
5978 /* Within function body, compute a type's size as soon it is laid out. */
5979 immediate_size_expand++;
5981 /* Prevent ever trying to delete the first instruction of a function.
5982 Also tell final how to output a linenum before the function prologue.
5983 Note linenums could be missing, e.g. when compiling a Java .class file. */
5985 emit_line_note (filename, line);
5987 /* Make sure first insn is a note even if we don't want linenums.
5988 This makes sure the first insn will never be deleted.
5989 Also, final expects a note to appear there. */
5990 emit_note (NULL_PTR, NOTE_INSN_DELETED);
5992 /* Set flags used by final.c. */
5993 if (aggregate_value_p (DECL_RESULT (subr)))
5995 #ifdef PCC_STATIC_STRUCT_RETURN
5996 current_function_returns_pcc_struct = 1;
5998 current_function_returns_struct = 1;
6001 /* Warn if this value is an aggregate type,
6002 regardless of which calling convention we are using for it. */
6003 if (warn_aggregate_return
6004 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6005 warning ("function returns an aggregate");
6007 current_function_returns_pointer
6008 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
6011 /* Make sure all values used by the optimization passes have sane
6014 init_function_for_compilation ()
6018 /* No prologue/epilogue insns yet. */
6019 VARRAY_GROW (prologue, 0);
6020 VARRAY_GROW (epilogue, 0);
6021 VARRAY_GROW (sibcall_epilogue, 0);
6024 /* Indicate that the current function uses extra args
6025 not explicitly mentioned in the argument list in any fashion. */
6030 current_function_varargs = 1;
6033 /* Expand a call to __main at the beginning of a possible main function. */
6035 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6036 #undef HAS_INIT_SECTION
6037 #define HAS_INIT_SECTION
6041 expand_main_function ()
6043 #if !defined (HAS_INIT_SECTION)
6044 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, NAME__MAIN), 0,
6046 #endif /* not HAS_INIT_SECTION */
6049 extern struct obstack permanent_obstack;
6051 /* Start the RTL for a new function, and set variables used for
6053 SUBR is the FUNCTION_DECL node.
6054 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6055 the function's parameters, which must be run at any return statement. */
6058 expand_function_start (subr, parms_have_cleanups)
6060 int parms_have_cleanups;
6063 rtx last_ptr = NULL_RTX;
6065 /* Make sure volatile mem refs aren't considered
6066 valid operands of arithmetic insns. */
6067 init_recog_no_volatile ();
6069 /* Set this before generating any memory accesses. */
6070 current_function_check_memory_usage
6071 = (flag_check_memory_usage
6072 && ! DECL_NO_CHECK_MEMORY_USAGE (current_function_decl));
6074 current_function_instrument_entry_exit
6075 = (flag_instrument_function_entry_exit
6076 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6078 current_function_limit_stack
6079 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6081 /* If function gets a static chain arg, store it in the stack frame.
6082 Do this first, so it gets the first stack slot offset. */
6083 if (current_function_needs_context)
6085 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
6087 /* Delay copying static chain if it is not a register to avoid
6088 conflicts with regs used for parameters. */
6089 if (! SMALL_REGISTER_CLASSES
6090 || GET_CODE (static_chain_incoming_rtx) == REG)
6091 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6094 /* If the parameters of this function need cleaning up, get a label
6095 for the beginning of the code which executes those cleanups. This must
6096 be done before doing anything with return_label. */
6097 if (parms_have_cleanups)
6098 cleanup_label = gen_label_rtx ();
6102 /* Make the label for return statements to jump to, if this machine
6103 does not have a one-instruction return and uses an epilogue,
6104 or if it returns a structure, or if it has parm cleanups. */
6106 if (cleanup_label == 0 && HAVE_return
6107 && ! current_function_instrument_entry_exit
6108 && ! current_function_returns_pcc_struct
6109 && ! (current_function_returns_struct && ! optimize))
6112 return_label = gen_label_rtx ();
6114 return_label = gen_label_rtx ();
6117 /* Initialize rtx used to return the value. */
6118 /* Do this before assign_parms so that we copy the struct value address
6119 before any library calls that assign parms might generate. */
6121 /* Decide whether to return the value in memory or in a register. */
6122 if (aggregate_value_p (DECL_RESULT (subr)))
6124 /* Returning something that won't go in a register. */
6125 register rtx value_address = 0;
6127 #ifdef PCC_STATIC_STRUCT_RETURN
6128 if (current_function_returns_pcc_struct)
6130 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6131 value_address = assemble_static_space (size);
6136 /* Expect to be passed the address of a place to store the value.
6137 If it is passed as an argument, assign_parms will take care of
6139 if (struct_value_incoming_rtx)
6141 value_address = gen_reg_rtx (Pmode);
6142 emit_move_insn (value_address, struct_value_incoming_rtx);
6147 DECL_RTL (DECL_RESULT (subr))
6148 = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
6149 set_mem_attributes (DECL_RTL (DECL_RESULT (subr)),
6150 DECL_RESULT (subr), 1);
6153 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6154 /* If return mode is void, this decl rtl should not be used. */
6155 DECL_RTL (DECL_RESULT (subr)) = 0;
6156 else if (parms_have_cleanups || current_function_instrument_entry_exit)
6158 /* If function will end with cleanup code for parms,
6159 compute the return values into a pseudo reg,
6160 which we will copy into the true return register
6161 after the cleanups are done. */
6163 enum machine_mode mode = DECL_MODE (DECL_RESULT (subr));
6165 #ifdef PROMOTE_FUNCTION_RETURN
6166 tree type = TREE_TYPE (DECL_RESULT (subr));
6167 int unsignedp = TREE_UNSIGNED (type);
6169 mode = promote_mode (type, mode, &unsignedp, 1);
6172 DECL_RTL (DECL_RESULT (subr)) = gen_reg_rtx (mode);
6175 /* Scalar, returned in a register. */
6177 DECL_RTL (DECL_RESULT (subr))
6178 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)), subr, 1);
6180 /* Mark this reg as the function's return value. */
6181 if (GET_CODE (DECL_RTL (DECL_RESULT (subr))) == REG)
6183 REG_FUNCTION_VALUE_P (DECL_RTL (DECL_RESULT (subr))) = 1;
6184 /* Needed because we may need to move this to memory
6185 in case it's a named return value whose address is taken. */
6186 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6190 /* Initialize rtx for parameters and local variables.
6191 In some cases this requires emitting insns. */
6193 assign_parms (subr);
6195 /* Copy the static chain now if it wasn't a register. The delay is to
6196 avoid conflicts with the parameter passing registers. */
6198 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6199 if (GET_CODE (static_chain_incoming_rtx) != REG)
6200 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6202 /* The following was moved from init_function_start.
6203 The move is supposed to make sdb output more accurate. */
6204 /* Indicate the beginning of the function body,
6205 as opposed to parm setup. */
6206 emit_note (NULL_PTR, NOTE_INSN_FUNCTION_BEG);
6208 if (GET_CODE (get_last_insn ()) != NOTE)
6209 emit_note (NULL_PTR, NOTE_INSN_DELETED);
6210 parm_birth_insn = get_last_insn ();
6212 context_display = 0;
6213 if (current_function_needs_context)
6215 /* Fetch static chain values for containing functions. */
6216 tem = decl_function_context (current_function_decl);
6217 /* Copy the static chain pointer into a pseudo. If we have
6218 small register classes, copy the value from memory if
6219 static_chain_incoming_rtx is a REG. */
6222 /* If the static chain originally came in a register, put it back
6223 there, then move it out in the next insn. The reason for
6224 this peculiar code is to satisfy function integration. */
6225 if (SMALL_REGISTER_CLASSES
6226 && GET_CODE (static_chain_incoming_rtx) == REG)
6227 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6228 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6233 tree rtlexp = make_node (RTL_EXPR);
6235 RTL_EXPR_RTL (rtlexp) = last_ptr;
6236 context_display = tree_cons (tem, rtlexp, context_display);
6237 tem = decl_function_context (tem);
6240 /* Chain thru stack frames, assuming pointer to next lexical frame
6241 is found at the place we always store it. */
6242 #ifdef FRAME_GROWS_DOWNWARD
6243 last_ptr = plus_constant (last_ptr, -GET_MODE_SIZE (Pmode));
6245 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr));
6246 MEM_ALIAS_SET (last_ptr) = get_frame_alias_set ();
6247 last_ptr = copy_to_reg (last_ptr);
6249 /* If we are not optimizing, ensure that we know that this
6250 piece of context is live over the entire function. */
6252 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6257 if (current_function_instrument_entry_exit)
6259 rtx fun = DECL_RTL (current_function_decl);
6260 if (GET_CODE (fun) == MEM)
6261 fun = XEXP (fun, 0);
6264 emit_library_call (profile_function_entry_libfunc, 0, VOIDmode, 2,
6266 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6268 hard_frame_pointer_rtx),
6272 /* After the display initializations is where the tail-recursion label
6273 should go, if we end up needing one. Ensure we have a NOTE here
6274 since some things (like trampolines) get placed before this. */
6275 tail_recursion_reentry = emit_note (NULL_PTR, NOTE_INSN_DELETED);
6277 /* Evaluate now the sizes of any types declared among the arguments. */
6278 for (tem = nreverse (get_pending_sizes ()); tem; tem = TREE_CHAIN (tem))
6280 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode,
6281 EXPAND_MEMORY_USE_BAD);
6282 /* Flush the queue in case this parameter declaration has
6287 /* Make sure there is a line number after the function entry setup code. */
6288 force_next_line_note ();
6291 /* Undo the effects of init_dummy_function_start. */
6293 expand_dummy_function_end ()
6295 /* End any sequences that failed to be closed due to syntax errors. */
6296 while (in_sequence_p ())
6299 /* Outside function body, can't compute type's actual size
6300 until next function's body starts. */
6302 free_after_parsing (cfun);
6303 free_after_compilation (cfun);
6308 /* Call DOIT for each hard register used as a return value from
6309 the current function. */
6312 diddle_return_value (doit, arg)
6313 void (*doit) PARAMS ((rtx, void *));
6316 rtx outgoing = current_function_return_rtx;
6322 pcc = (current_function_returns_struct
6323 || current_function_returns_pcc_struct);
6325 if ((GET_CODE (outgoing) == REG
6326 && REGNO (outgoing) >= FIRST_PSEUDO_REGISTER)
6329 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
6331 /* A PCC-style return returns a pointer to the memory in which
6332 the structure is stored. */
6334 type = build_pointer_type (type);
6336 #ifdef FUNCTION_OUTGOING_VALUE
6337 outgoing = FUNCTION_OUTGOING_VALUE (type, current_function_decl);
6339 outgoing = FUNCTION_VALUE (type, current_function_decl);
6341 /* If this is a BLKmode structure being returned in registers, then use
6342 the mode computed in expand_return. */
6343 if (GET_MODE (outgoing) == BLKmode)
6345 GET_MODE (DECL_RTL (DECL_RESULT (current_function_decl))));
6346 REG_FUNCTION_VALUE_P (outgoing) = 1;
6349 if (GET_CODE (outgoing) == REG)
6350 (*doit) (outgoing, arg);
6351 else if (GET_CODE (outgoing) == PARALLEL)
6355 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6357 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6359 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6366 do_clobber_return_reg (reg, arg)
6368 void *arg ATTRIBUTE_UNUSED;
6370 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6374 clobber_return_register ()
6376 diddle_return_value (do_clobber_return_reg, NULL);
6380 do_use_return_reg (reg, arg)
6382 void *arg ATTRIBUTE_UNUSED;
6384 emit_insn (gen_rtx_USE (VOIDmode, reg));
6388 use_return_register ()
6390 diddle_return_value (do_use_return_reg, NULL);
6393 /* Generate RTL for the end of the current function.
6394 FILENAME and LINE are the current position in the source file.
6396 It is up to language-specific callers to do cleanups for parameters--
6397 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
6400 expand_function_end (filename, line, end_bindings)
6401 const char *filename;
6407 #ifdef TRAMPOLINE_TEMPLATE
6408 static rtx initial_trampoline;
6411 finish_expr_for_function ();
6413 #ifdef NON_SAVING_SETJMP
6414 /* Don't put any variables in registers if we call setjmp
6415 on a machine that fails to restore the registers. */
6416 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6418 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6419 setjmp_protect (DECL_INITIAL (current_function_decl));
6421 setjmp_protect_args ();
6425 /* Save the argument pointer if a save area was made for it. */
6426 if (arg_pointer_save_area)
6428 /* arg_pointer_save_area may not be a valid memory address, so we
6429 have to check it and fix it if necessary. */
6432 emit_move_insn (validize_mem (arg_pointer_save_area),
6433 virtual_incoming_args_rtx);
6434 seq = gen_sequence ();
6436 emit_insn_before (seq, tail_recursion_reentry);
6439 /* Initialize any trampolines required by this function. */
6440 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6442 tree function = TREE_PURPOSE (link);
6443 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6444 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6445 #ifdef TRAMPOLINE_TEMPLATE
6450 #ifdef TRAMPOLINE_TEMPLATE
6451 /* First make sure this compilation has a template for
6452 initializing trampolines. */
6453 if (initial_trampoline == 0)
6455 end_temporary_allocation ();
6457 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6458 resume_temporary_allocation ();
6460 ggc_add_rtx_root (&initial_trampoline, 1);
6464 /* Generate insns to initialize the trampoline. */
6466 tramp = round_trampoline_addr (XEXP (tramp, 0));
6467 #ifdef TRAMPOLINE_TEMPLATE
6468 blktramp = change_address (initial_trampoline, BLKmode, tramp);
6469 emit_block_move (blktramp, initial_trampoline,
6470 GEN_INT (TRAMPOLINE_SIZE),
6471 TRAMPOLINE_ALIGNMENT);
6473 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6477 /* Put those insns at entry to the containing function (this one). */
6478 emit_insns_before (seq, tail_recursion_reentry);
6481 /* If we are doing stack checking and this function makes calls,
6482 do a stack probe at the start of the function to ensure we have enough
6483 space for another stack frame. */
6484 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6488 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6489 if (GET_CODE (insn) == CALL_INSN)
6492 probe_stack_range (STACK_CHECK_PROTECT,
6493 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6496 emit_insns_before (seq, tail_recursion_reentry);
6501 /* Warn about unused parms if extra warnings were specified. */
6502 /* Either ``-W -Wunused'' or ``-Wunused-parameter'' enables this
6503 warning. WARN_UNUSED_PARAMETER is negative when set by
6505 if (warn_unused_parameter > 0
6506 || (warn_unused_parameter < 0 && extra_warnings))
6510 for (decl = DECL_ARGUMENTS (current_function_decl);
6511 decl; decl = TREE_CHAIN (decl))
6512 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6513 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6514 warning_with_decl (decl, "unused parameter `%s'");
6517 /* Delete handlers for nonlocal gotos if nothing uses them. */
6518 if (nonlocal_goto_handler_slots != 0
6519 && ! current_function_has_nonlocal_label)
6522 /* End any sequences that failed to be closed due to syntax errors. */
6523 while (in_sequence_p ())
6526 /* Outside function body, can't compute type's actual size
6527 until next function's body starts. */
6528 immediate_size_expand--;
6530 clear_pending_stack_adjust ();
6531 do_pending_stack_adjust ();
6533 /* Mark the end of the function body.
6534 If control reaches this insn, the function can drop through
6535 without returning a value. */
6536 emit_note (NULL_PTR, NOTE_INSN_FUNCTION_END);
6538 /* Must mark the last line number note in the function, so that the test
6539 coverage code can avoid counting the last line twice. This just tells
6540 the code to ignore the immediately following line note, since there
6541 already exists a copy of this note somewhere above. This line number
6542 note is still needed for debugging though, so we can't delete it. */
6543 if (flag_test_coverage)
6544 emit_note (NULL_PTR, NOTE_INSN_REPEATED_LINE_NUMBER);
6546 /* Output a linenumber for the end of the function.
6547 SDB depends on this. */
6548 emit_line_note_force (filename, line);
6550 /* Output the label for the actual return from the function,
6551 if one is expected. This happens either because a function epilogue
6552 is used instead of a return instruction, or because a return was done
6553 with a goto in order to run local cleanups, or because of pcc-style
6554 structure returning. */
6558 /* Before the return label, clobber the return registers so that
6559 they are not propogated live to the rest of the function. This
6560 can only happen with functions that drop through; if there had
6561 been a return statement, there would have either been a return
6562 rtx, or a jump to the return label. */
6563 clobber_return_register ();
6565 emit_label (return_label);
6568 /* C++ uses this. */
6570 expand_end_bindings (0, 0, 0);
6572 /* Now handle any leftover exception regions that may have been
6573 created for the parameters. */
6575 rtx last = get_last_insn ();
6578 expand_leftover_cleanups ();
6580 /* If there are any catch_clauses remaining, output them now. */
6581 emit_insns (catch_clauses);
6582 catch_clauses = catch_clauses_last = NULL_RTX;
6583 /* If the above emitted any code, may sure we jump around it. */
6584 if (last != get_last_insn ())
6586 label = gen_label_rtx ();
6587 last = emit_jump_insn_after (gen_jump (label), last);
6588 last = emit_barrier_after (last);
6593 if (current_function_instrument_entry_exit)
6595 rtx fun = DECL_RTL (current_function_decl);
6596 if (GET_CODE (fun) == MEM)
6597 fun = XEXP (fun, 0);
6600 emit_library_call (profile_function_exit_libfunc, 0, VOIDmode, 2,
6602 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6604 hard_frame_pointer_rtx),
6608 /* If we had calls to alloca, and this machine needs
6609 an accurate stack pointer to exit the function,
6610 insert some code to save and restore the stack pointer. */
6611 #ifdef EXIT_IGNORE_STACK
6612 if (! EXIT_IGNORE_STACK)
6614 if (current_function_calls_alloca)
6618 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
6619 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
6622 /* If scalar return value was computed in a pseudo-reg,
6623 copy that to the hard return register. */
6624 if (DECL_RTL (DECL_RESULT (current_function_decl)) != 0
6625 && GET_CODE (DECL_RTL (DECL_RESULT (current_function_decl))) == REG
6626 && (REGNO (DECL_RTL (DECL_RESULT (current_function_decl)))
6627 >= FIRST_PSEUDO_REGISTER))
6629 rtx real_decl_result;
6631 #ifdef FUNCTION_OUTGOING_VALUE
6633 = FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl)),
6634 current_function_decl);
6637 = FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl)),
6638 current_function_decl);
6640 REG_FUNCTION_VALUE_P (real_decl_result) = 1;
6641 /* If this is a BLKmode structure being returned in registers, then use
6642 the mode computed in expand_return. */
6643 if (GET_MODE (real_decl_result) == BLKmode)
6644 PUT_MODE (real_decl_result,
6645 GET_MODE (DECL_RTL (DECL_RESULT (current_function_decl))));
6646 emit_move_insn (real_decl_result,
6647 DECL_RTL (DECL_RESULT (current_function_decl)));
6649 /* The delay slot scheduler assumes that current_function_return_rtx
6650 holds the hard register containing the return value, not a temporary
6652 current_function_return_rtx = real_decl_result;
6655 /* If returning a structure, arrange to return the address of the value
6656 in a place where debuggers expect to find it.
6658 If returning a structure PCC style,
6659 the caller also depends on this value.
6660 And current_function_returns_pcc_struct is not necessarily set. */
6661 if (current_function_returns_struct
6662 || current_function_returns_pcc_struct)
6665 XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
6666 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
6667 #ifdef FUNCTION_OUTGOING_VALUE
6669 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
6670 current_function_decl);
6673 = FUNCTION_VALUE (build_pointer_type (type),
6674 current_function_decl);
6677 /* Mark this as a function return value so integrate will delete the
6678 assignment and USE below when inlining this function. */
6679 REG_FUNCTION_VALUE_P (outgoing) = 1;
6681 emit_move_insn (outgoing, value_address);
6684 /* ??? This should no longer be necessary since stupid is no longer with
6685 us, but there are some parts of the compiler (eg reload_combine, and
6686 sh mach_dep_reorg) that still try and compute their own lifetime info
6687 instead of using the general framework. */
6688 use_return_register ();
6690 /* If this is an implementation of __throw, do what's necessary to
6691 communicate between __builtin_eh_return and the epilogue. */
6692 expand_eh_return ();
6694 /* Output a return insn if we are using one.
6695 Otherwise, let the rtl chain end here, to drop through
6696 into the epilogue. */
6701 emit_jump_insn (gen_return ());
6706 /* Fix up any gotos that jumped out to the outermost
6707 binding level of the function.
6708 Must follow emitting RETURN_LABEL. */
6710 /* If you have any cleanups to do at this point,
6711 and they need to create temporary variables,
6712 then you will lose. */
6713 expand_fixups (get_insns ());
6716 /* Extend a vector that records the INSN_UIDs of INSNS (either a
6717 sequence or a single insn). */
6720 record_insns (insns, vecp)
6724 if (GET_CODE (insns) == SEQUENCE)
6726 int len = XVECLEN (insns, 0);
6727 int i = VARRAY_SIZE (*vecp);
6729 VARRAY_GROW (*vecp, i + len);
6732 VARRAY_INT (*vecp, i) = INSN_UID (XVECEXP (insns, 0, len));
6738 int i = VARRAY_SIZE (*vecp);
6739 VARRAY_GROW (*vecp, i + 1);
6740 VARRAY_INT (*vecp, i) = INSN_UID (insns);
6744 /* Determine how many INSN_UIDs in VEC are part of INSN. */
6747 contains (insn, vec)
6753 if (GET_CODE (insn) == INSN
6754 && GET_CODE (PATTERN (insn)) == SEQUENCE)
6757 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
6758 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
6759 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
6765 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
6766 if (INSN_UID (insn) == VARRAY_INT (vec, j))
6773 prologue_epilogue_contains (insn)
6776 if (contains (insn, prologue))
6778 if (contains (insn, epilogue))
6784 sibcall_epilogue_contains (insn)
6787 if (sibcall_epilogue)
6788 return contains (insn, sibcall_epilogue);
6793 /* Insert gen_return at the end of block BB. This also means updating
6794 block_for_insn appropriately. */
6797 emit_return_into_block (bb, line_note)
6803 p = NEXT_INSN (bb->end);
6804 end = emit_jump_insn_after (gen_return (), bb->end);
6806 emit_line_note_after (NOTE_SOURCE_FILE (line_note),
6807 NOTE_LINE_NUMBER (line_note), bb->end);
6811 set_block_for_insn (p, bb);
6818 #endif /* HAVE_return */
6820 #ifdef HAVE_epilogue
6822 /* Modify SEQ, a SEQUENCE that is part of the epilogue, to no modifications
6823 to the stack pointer. */
6826 keep_stack_depressed (seq)
6830 rtx sp_from_reg = 0;
6831 int sp_modified_unknown = 0;
6833 /* If the epilogue is just a single instruction, it's OK as is */
6835 if (GET_CODE (seq) != SEQUENCE) return;
6837 /* Scan all insns in SEQ looking for ones that modified the stack
6838 pointer. Record if it modified the stack pointer by copying it
6839 from the frame pointer or if it modified it in some other way.
6840 Then modify any subsequent stack pointer references to take that
6841 into account. We start by only allowing SP to be copied from a
6842 register (presumably FP) and then be subsequently referenced. */
6844 for (i = 0; i < XVECLEN (seq, 0); i++)
6846 rtx insn = XVECEXP (seq, 0, i);
6848 if (GET_RTX_CLASS (GET_CODE (insn)) != 'i')
6851 if (reg_set_p (stack_pointer_rtx, insn))
6853 rtx set = single_set (insn);
6855 /* If SP is set as a side-effect, we can't support this. */
6859 if (GET_CODE (SET_SRC (set)) == REG)
6860 sp_from_reg = SET_SRC (set);
6862 sp_modified_unknown = 1;
6864 /* Don't allow the SP modification to happen. */
6865 PUT_CODE (insn, NOTE);
6866 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
6867 NOTE_SOURCE_FILE (insn) = 0;
6869 else if (reg_referenced_p (stack_pointer_rtx, PATTERN (insn)))
6871 if (sp_modified_unknown)
6874 else if (sp_from_reg != 0)
6876 = replace_rtx (PATTERN (insn), stack_pointer_rtx, sp_from_reg);
6882 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
6883 this into place with notes indicating where the prologue ends and where
6884 the epilogue begins. Update the basic block information when possible. */
6887 thread_prologue_and_epilogue_insns (f)
6888 rtx f ATTRIBUTE_UNUSED;
6893 #ifdef HAVE_prologue
6894 rtx prologue_end = NULL_RTX;
6896 #if defined (HAVE_epilogue) || defined(HAVE_return)
6897 rtx epilogue_end = NULL_RTX;
6900 #ifdef HAVE_prologue
6904 seq = gen_prologue ();
6907 /* Retain a map of the prologue insns. */
6908 if (GET_CODE (seq) != SEQUENCE)
6910 record_insns (seq, &prologue);
6911 prologue_end = emit_note (NULL, NOTE_INSN_PROLOGUE_END);
6913 seq = gen_sequence ();
6916 /* If optimization is off, and perhaps in an empty function,
6917 the entry block will have no successors. */
6918 if (ENTRY_BLOCK_PTR->succ)
6920 /* Can't deal with multiple successsors of the entry block. */
6921 if (ENTRY_BLOCK_PTR->succ->succ_next)
6924 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
6928 emit_insn_after (seq, f);
6932 /* If the exit block has no non-fake predecessors, we don't need
6934 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
6935 if ((e->flags & EDGE_FAKE) == 0)
6941 if (optimize && HAVE_return)
6943 /* If we're allowed to generate a simple return instruction,
6944 then by definition we don't need a full epilogue. Examine
6945 the block that falls through to EXIT. If it does not
6946 contain any code, examine its predecessors and try to
6947 emit (conditional) return instructions. */
6953 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
6954 if (e->flags & EDGE_FALLTHRU)
6960 /* Verify that there are no active instructions in the last block. */
6962 while (label && GET_CODE (label) != CODE_LABEL)
6964 if (active_insn_p (label))
6966 label = PREV_INSN (label);
6969 if (last->head == label && GET_CODE (label) == CODE_LABEL)
6971 rtx epilogue_line_note = NULL_RTX;
6973 /* Locate the line number associated with the closing brace,
6974 if we can find one. */
6975 for (seq = get_last_insn ();
6976 seq && ! active_insn_p (seq);
6977 seq = PREV_INSN (seq))
6978 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
6980 epilogue_line_note = seq;
6984 for (e = last->pred; e; e = e_next)
6986 basic_block bb = e->src;
6989 e_next = e->pred_next;
6990 if (bb == ENTRY_BLOCK_PTR)
6994 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
6997 /* If we have an unconditional jump, we can replace that
6998 with a simple return instruction. */
6999 if (simplejump_p (jump))
7001 emit_return_into_block (bb, epilogue_line_note);
7002 flow_delete_insn (jump);
7005 /* If we have a conditional jump, we can try to replace
7006 that with a conditional return instruction. */
7007 else if (condjump_p (jump))
7011 ret = SET_SRC (PATTERN (jump));
7012 if (GET_CODE (XEXP (ret, 1)) == LABEL_REF)
7013 loc = &XEXP (ret, 1);
7015 loc = &XEXP (ret, 2);
7016 ret = gen_rtx_RETURN (VOIDmode);
7018 if (! validate_change (jump, loc, ret, 0))
7020 if (JUMP_LABEL (jump))
7021 LABEL_NUSES (JUMP_LABEL (jump))--;
7023 /* If this block has only one successor, it both jumps
7024 and falls through to the fallthru block, so we can't
7026 if (bb->succ->succ_next == NULL)
7032 /* Fix up the CFG for the successful change we just made. */
7033 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7036 /* Emit a return insn for the exit fallthru block. Whether
7037 this is still reachable will be determined later. */
7039 emit_barrier_after (last->end);
7040 emit_return_into_block (last, epilogue_line_note);
7041 epilogue_end = last->end;
7046 #ifdef HAVE_epilogue
7049 /* Find the edge that falls through to EXIT. Other edges may exist
7050 due to RETURN instructions, but those don't need epilogues.
7051 There really shouldn't be a mixture -- either all should have
7052 been converted or none, however... */
7054 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7055 if (e->flags & EDGE_FALLTHRU)
7061 epilogue_end = emit_note (NULL, NOTE_INSN_EPILOGUE_BEG);
7063 seq = gen_epilogue ();
7065 /* If this function returns with the stack depressed, massage
7066 the epilogue to actually do that. */
7067 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7068 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7069 keep_stack_depressed (seq);
7071 emit_jump_insn (seq);
7073 /* Retain a map of the epilogue insns. */
7074 if (GET_CODE (seq) != SEQUENCE)
7076 record_insns (seq, &epilogue);
7078 seq = gen_sequence ();
7081 insert_insn_on_edge (seq, e);
7088 commit_edge_insertions ();
7090 #ifdef HAVE_sibcall_epilogue
7091 /* Emit sibling epilogues before any sibling call sites. */
7092 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7094 basic_block bb = e->src;
7099 if (GET_CODE (insn) != CALL_INSN
7100 || ! SIBLING_CALL_P (insn))
7104 seq = gen_sibcall_epilogue ();
7107 i = PREV_INSN (insn);
7108 newinsn = emit_insn_before (seq, insn);
7110 /* Update the UID to basic block map. */
7111 for (i = NEXT_INSN (i); i != insn; i = NEXT_INSN (i))
7112 set_block_for_insn (i, bb);
7114 /* Retain a map of the epilogue insns. Used in life analysis to
7115 avoid getting rid of sibcall epilogue insns. */
7116 record_insns (GET_CODE (seq) == SEQUENCE
7117 ? seq : newinsn, &sibcall_epilogue);
7121 #ifdef HAVE_prologue
7126 /* GDB handles `break f' by setting a breakpoint on the first
7127 line note after the prologue. Which means (1) that if
7128 there are line number notes before where we inserted the
7129 prologue we should move them, and (2) we should generate a
7130 note before the end of the first basic block, if there isn't
7131 one already there. */
7133 for (insn = prologue_end; insn; insn = prev)
7135 prev = PREV_INSN (insn);
7136 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7138 /* Note that we cannot reorder the first insn in the
7139 chain, since rest_of_compilation relies on that
7140 remaining constant. */
7143 reorder_insns (insn, insn, prologue_end);
7147 /* Find the last line number note in the first block. */
7148 for (insn = BASIC_BLOCK (0)->end;
7149 insn != prologue_end;
7150 insn = PREV_INSN (insn))
7151 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7154 /* If we didn't find one, make a copy of the first line number
7158 for (insn = next_active_insn (prologue_end);
7160 insn = PREV_INSN (insn))
7161 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7163 emit_line_note_after (NOTE_SOURCE_FILE (insn),
7164 NOTE_LINE_NUMBER (insn),
7171 #ifdef HAVE_epilogue
7176 /* Similarly, move any line notes that appear after the epilogue.
7177 There is no need, however, to be quite so anal about the existance
7179 for (insn = epilogue_end; insn; insn = next)
7181 next = NEXT_INSN (insn);
7182 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7183 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7189 /* Reposition the prologue-end and epilogue-begin notes after instruction
7190 scheduling and delayed branch scheduling. */
7193 reposition_prologue_and_epilogue_notes (f)
7194 rtx f ATTRIBUTE_UNUSED;
7196 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7199 if ((len = VARRAY_SIZE (prologue)) > 0)
7201 register rtx insn, note = 0;
7203 /* Scan from the beginning until we reach the last prologue insn.
7204 We apparently can't depend on basic_block_{head,end} after
7206 for (insn = f; len && insn; insn = NEXT_INSN (insn))
7208 if (GET_CODE (insn) == NOTE)
7210 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
7213 else if ((len -= contains (insn, prologue)) == 0)
7216 /* Find the prologue-end note if we haven't already, and
7217 move it to just after the last prologue insn. */
7220 for (note = insn; (note = NEXT_INSN (note));)
7221 if (GET_CODE (note) == NOTE
7222 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
7226 next = NEXT_INSN (note);
7228 /* Whether or not we can depend on BLOCK_HEAD,
7229 attempt to keep it up-to-date. */
7230 if (BLOCK_HEAD (0) == note)
7231 BLOCK_HEAD (0) = next;
7234 add_insn_after (note, insn);
7239 if ((len = VARRAY_SIZE (epilogue)) > 0)
7241 register rtx insn, note = 0;
7243 /* Scan from the end until we reach the first epilogue insn.
7244 We apparently can't depend on basic_block_{head,end} after
7246 for (insn = get_last_insn (); len && insn; insn = PREV_INSN (insn))
7248 if (GET_CODE (insn) == NOTE)
7250 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
7253 else if ((len -= contains (insn, epilogue)) == 0)
7255 /* Find the epilogue-begin note if we haven't already, and
7256 move it to just before the first epilogue insn. */
7259 for (note = insn; (note = PREV_INSN (note));)
7260 if (GET_CODE (note) == NOTE
7261 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
7265 /* Whether or not we can depend on BLOCK_HEAD,
7266 attempt to keep it up-to-date. */
7268 && BLOCK_HEAD (n_basic_blocks-1) == insn)
7269 BLOCK_HEAD (n_basic_blocks-1) = note;
7272 add_insn_before (note, insn);
7276 #endif /* HAVE_prologue or HAVE_epilogue */
7279 /* Mark T for GC. */
7283 struct temp_slot *t;
7287 ggc_mark_rtx (t->slot);
7288 ggc_mark_rtx (t->address);
7289 ggc_mark_tree (t->rtl_expr);
7295 /* Mark P for GC. */
7298 mark_function_status (p)
7307 ggc_mark_rtx (p->arg_offset_rtx);
7309 if (p->x_parm_reg_stack_loc)
7310 for (i = p->x_max_parm_reg, r = p->x_parm_reg_stack_loc;
7314 ggc_mark_rtx (p->return_rtx);
7315 ggc_mark_rtx (p->x_cleanup_label);
7316 ggc_mark_rtx (p->x_return_label);
7317 ggc_mark_rtx (p->x_save_expr_regs);
7318 ggc_mark_rtx (p->x_stack_slot_list);
7319 ggc_mark_rtx (p->x_parm_birth_insn);
7320 ggc_mark_rtx (p->x_tail_recursion_label);
7321 ggc_mark_rtx (p->x_tail_recursion_reentry);
7322 ggc_mark_rtx (p->internal_arg_pointer);
7323 ggc_mark_rtx (p->x_arg_pointer_save_area);
7324 ggc_mark_tree (p->x_rtl_expr_chain);
7325 ggc_mark_rtx (p->x_last_parm_insn);
7326 ggc_mark_tree (p->x_context_display);
7327 ggc_mark_tree (p->x_trampoline_list);
7328 ggc_mark_rtx (p->epilogue_delay_list);
7330 mark_temp_slot (p->x_temp_slots);
7333 struct var_refs_queue *q = p->fixup_var_refs_queue;
7336 ggc_mark_rtx (q->modified);
7341 ggc_mark_rtx (p->x_nonlocal_goto_handler_slots);
7342 ggc_mark_rtx (p->x_nonlocal_goto_handler_labels);
7343 ggc_mark_rtx (p->x_nonlocal_goto_stack_level);
7344 ggc_mark_tree (p->x_nonlocal_labels);
7347 /* Mark the function chain ARG (which is really a struct function **)
7351 mark_function_chain (arg)
7354 struct function *f = *(struct function **) arg;
7356 for (; f; f = f->next_global)
7358 ggc_mark_tree (f->decl);
7360 mark_function_status (f);
7361 mark_eh_status (f->eh);
7362 mark_stmt_status (f->stmt);
7363 mark_expr_status (f->expr);
7364 mark_emit_status (f->emit);
7365 mark_varasm_status (f->varasm);
7367 if (mark_machine_status)
7368 (*mark_machine_status) (f);
7369 if (mark_lang_status)
7370 (*mark_lang_status) (f);
7372 if (f->original_arg_vector)
7373 ggc_mark_rtvec ((rtvec) f->original_arg_vector);
7374 if (f->original_decl_initial)
7375 ggc_mark_tree (f->original_decl_initial);
7379 /* Called once, at initialization, to initialize function.c. */
7382 init_function_once ()
7384 ggc_add_root (&all_functions, 1, sizeof all_functions,
7385 mark_function_chain);
7387 VARRAY_INT_INIT (prologue, 0, "prologue");
7388 VARRAY_INT_INIT (epilogue, 0, "epilogue");
7389 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");