1 /* Expands front end tree to back end RTL for GNU C-Compiler
2 Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
5 This file is part of GNU CC.
7 GNU CC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GNU CC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU CC; see the file COPYING. If not, write to
19 the Free Software Foundation, 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
22 /* This file handles the generation of rtl code from tree structure
23 at the level of the function as a whole.
24 It creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 `expand_function_start' is called at the beginning of a function,
28 before the function body is parsed, and `expand_function_end' is
29 called after parsing the body.
31 Call `assign_stack_local' to allocate a stack slot for a local variable.
32 This is usually done during the RTL generation for the function body,
33 but it can also be done in the reload pass when a pseudo-register does
34 not get a hard register.
36 Call `put_var_into_stack' when you learn, belatedly, that a variable
37 previously given a pseudo-register must in fact go in the stack.
38 This function changes the DECL_RTL to be a stack slot instead of a reg
39 then scans all the RTL instructions so far generated to correct them. */
50 #include "hard-reg-set.h"
51 #include "insn-config.h"
54 #include "basic-block.h"
60 #include "integrate.h"
62 #ifndef TRAMPOLINE_ALIGNMENT
63 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
66 #ifndef LOCAL_ALIGNMENT
67 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
70 #if !defined (PREFERRED_STACK_BOUNDARY) && defined (STACK_BOUNDARY)
71 #define PREFERRED_STACK_BOUNDARY STACK_BOUNDARY
74 /* Some systems use __main in a way incompatible with its use in gcc, in these
75 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
76 give the same symbol without quotes for an alternative entry point. You
77 must define both, or neither. */
79 #define NAME__MAIN "__main"
80 #define SYMBOL__MAIN __main
83 /* Round a value to the lowest integer less than it that is a multiple of
84 the required alignment. Avoid using division in case the value is
85 negative. Assume the alignment is a power of two. */
86 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
88 /* Similar, but round to the next highest integer that meets the
90 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
92 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
93 during rtl generation. If they are different register numbers, this is
94 always true. It may also be true if
95 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
96 generation. See fix_lexical_addr for details. */
98 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
99 #define NEED_SEPARATE_AP
102 /* Nonzero if function being compiled doesn't contain any calls
103 (ignoring the prologue and epilogue). This is set prior to
104 local register allocation and is valid for the remaining
106 int current_function_is_leaf;
108 /* Nonzero if function being compiled doesn't contain any instructions
109 that can throw an exception. This is set prior to final. */
111 int current_function_nothrow;
113 /* Nonzero if function being compiled doesn't modify the stack pointer
114 (ignoring the prologue and epilogue). This is only valid after
115 life_analysis has run. */
116 int current_function_sp_is_unchanging;
118 /* Nonzero if the function being compiled is a leaf function which only
119 uses leaf registers. This is valid after reload (specifically after
120 sched2) and is useful only if the port defines LEAF_REGISTERS. */
121 int current_function_uses_only_leaf_regs;
123 /* Nonzero once virtual register instantiation has been done.
124 assign_stack_local uses frame_pointer_rtx when this is nonzero.
125 calls.c:emit_library_call_value_1 uses it to set up
126 post-instantiation libcalls. */
127 int virtuals_instantiated;
129 /* These variables hold pointers to functions to create and destroy
130 target specific, per-function data structures. */
131 void (*init_machine_status) PARAMS ((struct function *));
132 void (*free_machine_status) PARAMS ((struct function *));
133 /* This variable holds a pointer to a function to register any
134 data items in the target specific, per-function data structure
135 that will need garbage collection. */
136 void (*mark_machine_status) PARAMS ((struct function *));
138 /* Likewise, but for language-specific data. */
139 void (*init_lang_status) PARAMS ((struct function *));
140 void (*save_lang_status) PARAMS ((struct function *));
141 void (*restore_lang_status) PARAMS ((struct function *));
142 void (*mark_lang_status) PARAMS ((struct function *));
143 void (*free_lang_status) PARAMS ((struct function *));
145 /* The FUNCTION_DECL for an inline function currently being expanded. */
146 tree inline_function_decl;
148 /* The currently compiled function. */
149 struct function *cfun = 0;
151 /* Global list of all compiled functions. */
152 struct function *all_functions = 0;
154 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
155 static varray_type prologue;
156 static varray_type epilogue;
158 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
160 static varray_type sibcall_epilogue;
162 /* In order to evaluate some expressions, such as function calls returning
163 structures in memory, we need to temporarily allocate stack locations.
164 We record each allocated temporary in the following structure.
166 Associated with each temporary slot is a nesting level. When we pop up
167 one level, all temporaries associated with the previous level are freed.
168 Normally, all temporaries are freed after the execution of the statement
169 in which they were created. However, if we are inside a ({...}) grouping,
170 the result may be in a temporary and hence must be preserved. If the
171 result could be in a temporary, we preserve it if we can determine which
172 one it is in. If we cannot determine which temporary may contain the
173 result, all temporaries are preserved. A temporary is preserved by
174 pretending it was allocated at the previous nesting level.
176 Automatic variables are also assigned temporary slots, at the nesting
177 level where they are defined. They are marked a "kept" so that
178 free_temp_slots will not free them. */
182 /* Points to next temporary slot. */
183 struct temp_slot *next;
184 /* The rtx to used to reference the slot. */
186 /* The rtx used to represent the address if not the address of the
187 slot above. May be an EXPR_LIST if multiple addresses exist. */
189 /* The alignment (in bits) of the slot. */
191 /* The size, in units, of the slot. */
193 /* The type of the object in the slot, or zero if it doesn't correspond
194 to a type. We use this to determine whether a slot can be reused.
195 It can be reused if objects of the type of the new slot will always
196 conflict with objects of the type of the old slot. */
198 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
200 /* Non-zero if this temporary is currently in use. */
202 /* Non-zero if this temporary has its address taken. */
204 /* Nesting level at which this slot is being used. */
206 /* Non-zero if this should survive a call to free_temp_slots. */
208 /* The offset of the slot from the frame_pointer, including extra space
209 for alignment. This info is for combine_temp_slots. */
210 HOST_WIDE_INT base_offset;
211 /* The size of the slot, including extra space for alignment. This
212 info is for combine_temp_slots. */
213 HOST_WIDE_INT full_size;
216 /* This structure is used to record MEMs or pseudos used to replace VAR, any
217 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
218 maintain this list in case two operands of an insn were required to match;
219 in that case we must ensure we use the same replacement. */
221 struct fixup_replacement
225 struct fixup_replacement *next;
228 struct insns_for_mem_entry {
229 /* The KEY in HE will be a MEM. */
230 struct hash_entry he;
231 /* These are the INSNS which reference the MEM. */
235 /* Forward declarations. */
237 static rtx assign_stack_local_1 PARAMS ((enum machine_mode, HOST_WIDE_INT,
238 int, struct function *));
239 static rtx assign_stack_temp_for_type PARAMS ((enum machine_mode,
240 HOST_WIDE_INT, int, tree));
241 static struct temp_slot *find_temp_slot_from_address PARAMS ((rtx));
242 static void put_reg_into_stack PARAMS ((struct function *, rtx, tree,
243 enum machine_mode, enum machine_mode,
244 int, unsigned int, int,
245 struct hash_table *));
246 static void schedule_fixup_var_refs PARAMS ((struct function *, rtx, tree,
248 struct hash_table *));
249 static void fixup_var_refs PARAMS ((rtx, enum machine_mode, int,
250 struct hash_table *));
251 static struct fixup_replacement
252 *find_fixup_replacement PARAMS ((struct fixup_replacement **, rtx));
253 static void fixup_var_refs_insns PARAMS ((rtx, rtx, enum machine_mode,
255 static void fixup_var_refs_insns_with_hash
256 PARAMS ((struct hash_table *, rtx,
257 enum machine_mode, int));
258 static void fixup_var_refs_insn PARAMS ((rtx, rtx, enum machine_mode,
260 static void fixup_var_refs_1 PARAMS ((rtx, enum machine_mode, rtx *, rtx,
261 struct fixup_replacement **));
262 static rtx fixup_memory_subreg PARAMS ((rtx, rtx, int));
263 static rtx walk_fixup_memory_subreg PARAMS ((rtx, rtx, int));
264 static rtx fixup_stack_1 PARAMS ((rtx, rtx));
265 static void optimize_bit_field PARAMS ((rtx, rtx, rtx *));
266 static void instantiate_decls PARAMS ((tree, int));
267 static void instantiate_decls_1 PARAMS ((tree, int));
268 static void instantiate_decl PARAMS ((rtx, HOST_WIDE_INT, int));
269 static rtx instantiate_new_reg PARAMS ((rtx, HOST_WIDE_INT *));
270 static int instantiate_virtual_regs_1 PARAMS ((rtx *, rtx, int));
271 static void delete_handlers PARAMS ((void));
272 static void pad_to_arg_alignment PARAMS ((struct args_size *, int,
273 struct args_size *));
274 #ifndef ARGS_GROW_DOWNWARD
275 static void pad_below PARAMS ((struct args_size *, enum machine_mode,
278 static rtx round_trampoline_addr PARAMS ((rtx));
279 static rtx adjust_trampoline_addr PARAMS ((rtx));
280 static tree *identify_blocks_1 PARAMS ((rtx, tree *, tree *, tree *));
281 static void reorder_blocks_0 PARAMS ((tree));
282 static void reorder_blocks_1 PARAMS ((rtx, tree, varray_type *));
283 static void reorder_fix_fragments PARAMS ((tree));
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 bool purge_addressof_1 PARAMS ((rtx *, rtx, int, int,
296 struct hash_table *));
297 static void purge_single_hard_subreg_set PARAMS ((rtx));
299 static void keep_stack_depressed PARAMS ((rtx));
301 static int is_addressof PARAMS ((rtx *, void *));
302 static struct hash_entry *insns_for_mem_newfunc PARAMS ((struct hash_entry *,
305 static unsigned long insns_for_mem_hash PARAMS ((hash_table_key));
306 static bool insns_for_mem_comp PARAMS ((hash_table_key, hash_table_key));
307 static int insns_for_mem_walk PARAMS ((rtx *, void *));
308 static void compute_insns_for_mem PARAMS ((rtx, rtx, struct hash_table *));
309 static void mark_temp_slot PARAMS ((struct temp_slot *));
310 static void mark_function_status PARAMS ((struct function *));
311 static void mark_function_chain PARAMS ((void *));
312 static void prepare_function_start PARAMS ((void));
313 static void do_clobber_return_reg PARAMS ((rtx, void *));
314 static void do_use_return_reg PARAMS ((rtx, void *));
316 /* Pointer to chain of `struct function' for containing functions. */
317 struct function *outer_function_chain;
319 /* Given a function decl for a containing function,
320 return the `struct function' for it. */
323 find_function_data (decl)
328 for (p = outer_function_chain; p; p = p->next)
335 /* Save the current context for compilation of a nested function.
336 This is called from language-specific code. The caller should use
337 the save_lang_status callback to save any language-specific state,
338 since this function knows only about language-independent
342 push_function_context_to (context)
345 struct function *p, *context_data;
349 context_data = (context == current_function_decl
351 : find_function_data (context));
352 context_data->contains_functions = 1;
356 init_dummy_function_start ();
359 p->next = outer_function_chain;
360 outer_function_chain = p;
361 p->fixup_var_refs_queue = 0;
363 if (save_lang_status)
364 (*save_lang_status) (p);
370 push_function_context ()
372 push_function_context_to (current_function_decl);
375 /* Restore the last saved context, at the end of a nested function.
376 This function is called from language-specific code. */
379 pop_function_context_from (context)
380 tree context ATTRIBUTE_UNUSED;
382 struct function *p = outer_function_chain;
383 struct var_refs_queue *queue;
384 struct var_refs_queue *next;
387 outer_function_chain = p->next;
389 current_function_decl = p->decl;
392 restore_emit_status (p);
394 if (restore_lang_status)
395 (*restore_lang_status) (p);
397 /* Finish doing put_var_into_stack for any of our variables
398 which became addressable during the nested function. */
399 for (queue = p->fixup_var_refs_queue; queue; queue = next)
402 fixup_var_refs (queue->modified, queue->promoted_mode,
403 queue->unsignedp, 0);
406 p->fixup_var_refs_queue = 0;
408 /* Reset variables that have known state during rtx generation. */
409 rtx_equal_function_value_matters = 1;
410 virtuals_instantiated = 0;
411 generating_concat_p = 1;
415 pop_function_context ()
417 pop_function_context_from (current_function_decl);
420 /* Clear out all parts of the state in F that can safely be discarded
421 after the function has been parsed, but not compiled, to let
422 garbage collection reclaim the memory. */
425 free_after_parsing (f)
428 /* f->expr->forced_labels is used by code generation. */
429 /* f->emit->regno_reg_rtx is used by code generation. */
430 /* f->varasm is used by code generation. */
431 /* f->eh->eh_return_stub_label is used by code generation. */
433 if (free_lang_status)
434 (*free_lang_status) (f);
435 free_stmt_status (f);
438 /* Clear out all parts of the state in F that can safely be discarded
439 after the function has been compiled, to let garbage collection
440 reclaim the memory. */
443 free_after_compilation (f)
446 struct temp_slot *ts;
447 struct temp_slot *next;
450 free_expr_status (f);
451 free_emit_status (f);
452 free_varasm_status (f);
454 if (free_machine_status)
455 (*free_machine_status) (f);
457 if (f->x_parm_reg_stack_loc)
458 free (f->x_parm_reg_stack_loc);
460 for (ts = f->x_temp_slots; ts; ts = next)
465 f->x_temp_slots = NULL;
467 f->arg_offset_rtx = NULL;
468 f->return_rtx = NULL;
469 f->internal_arg_pointer = NULL;
470 f->x_nonlocal_labels = NULL;
471 f->x_nonlocal_goto_handler_slots = NULL;
472 f->x_nonlocal_goto_handler_labels = NULL;
473 f->x_nonlocal_goto_stack_level = NULL;
474 f->x_cleanup_label = NULL;
475 f->x_return_label = NULL;
476 f->x_save_expr_regs = NULL;
477 f->x_stack_slot_list = NULL;
478 f->x_rtl_expr_chain = NULL;
479 f->x_tail_recursion_label = NULL;
480 f->x_tail_recursion_reentry = NULL;
481 f->x_arg_pointer_save_area = NULL;
482 f->x_clobber_return_insn = NULL;
483 f->x_context_display = NULL;
484 f->x_trampoline_list = NULL;
485 f->x_parm_birth_insn = NULL;
486 f->x_last_parm_insn = NULL;
487 f->x_parm_reg_stack_loc = NULL;
488 f->fixup_var_refs_queue = NULL;
489 f->original_arg_vector = NULL;
490 f->original_decl_initial = NULL;
491 f->inl_last_parm_insn = NULL;
492 f->epilogue_delay_list = NULL;
495 /* Allocate fixed slots in the stack frame of the current function. */
497 /* Return size needed for stack frame based on slots so far allocated in
499 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
500 the caller may have to do that. */
503 get_func_frame_size (f)
506 #ifdef FRAME_GROWS_DOWNWARD
507 return -f->x_frame_offset;
509 return f->x_frame_offset;
513 /* Return size needed for stack frame based on slots so far allocated.
514 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
515 the caller may have to do that. */
519 return get_func_frame_size (cfun);
522 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
523 with machine mode MODE.
525 ALIGN controls the amount of alignment for the address of the slot:
526 0 means according to MODE,
527 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
528 positive specifies alignment boundary in bits.
530 We do not round to stack_boundary here.
532 FUNCTION specifies the function to allocate in. */
535 assign_stack_local_1 (mode, size, align, function)
536 enum machine_mode mode;
539 struct function *function;
541 register rtx x, addr;
542 int bigend_correction = 0;
550 alignment = BIGGEST_ALIGNMENT;
552 alignment = GET_MODE_ALIGNMENT (mode);
554 /* Allow the target to (possibly) increase the alignment of this
556 type = type_for_mode (mode, 0);
558 alignment = LOCAL_ALIGNMENT (type, alignment);
560 alignment /= BITS_PER_UNIT;
562 else if (align == -1)
564 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
565 size = CEIL_ROUND (size, alignment);
568 alignment = align / BITS_PER_UNIT;
570 #ifdef FRAME_GROWS_DOWNWARD
571 function->x_frame_offset -= size;
574 /* Ignore alignment we can't do with expected alignment of the boundary. */
575 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
576 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
578 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
579 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
581 /* Round frame offset to that alignment.
582 We must be careful here, since FRAME_OFFSET might be negative and
583 division with a negative dividend isn't as well defined as we might
584 like. So we instead assume that ALIGNMENT is a power of two and
585 use logical operations which are unambiguous. */
586 #ifdef FRAME_GROWS_DOWNWARD
587 function->x_frame_offset = FLOOR_ROUND (function->x_frame_offset, alignment);
589 function->x_frame_offset = CEIL_ROUND (function->x_frame_offset, alignment);
592 /* On a big-endian machine, if we are allocating more space than we will use,
593 use the least significant bytes of those that are allocated. */
594 if (BYTES_BIG_ENDIAN && mode != BLKmode)
595 bigend_correction = size - GET_MODE_SIZE (mode);
597 /* If we have already instantiated virtual registers, return the actual
598 address relative to the frame pointer. */
599 if (function == cfun && virtuals_instantiated)
600 addr = plus_constant (frame_pointer_rtx,
601 (frame_offset + bigend_correction
602 + STARTING_FRAME_OFFSET));
604 addr = plus_constant (virtual_stack_vars_rtx,
605 function->x_frame_offset + bigend_correction);
607 #ifndef FRAME_GROWS_DOWNWARD
608 function->x_frame_offset += size;
611 x = gen_rtx_MEM (mode, addr);
613 function->x_stack_slot_list
614 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
619 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
623 assign_stack_local (mode, size, align)
624 enum machine_mode mode;
628 return assign_stack_local_1 (mode, size, align, cfun);
631 /* Allocate a temporary stack slot and record it for possible later
634 MODE is the machine mode to be given to the returned rtx.
636 SIZE is the size in units of the space required. We do no rounding here
637 since assign_stack_local will do any required rounding.
639 KEEP is 1 if this slot is to be retained after a call to
640 free_temp_slots. Automatic variables for a block are allocated
641 with this flag. KEEP is 2 if we allocate a longer term temporary,
642 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
643 if we are to allocate something at an inner level to be treated as
644 a variable in the block (e.g., a SAVE_EXPR).
646 TYPE is the type that will be used for the stack slot. */
649 assign_stack_temp_for_type (mode, size, keep, type)
650 enum machine_mode mode;
656 struct temp_slot *p, *best_p = 0;
658 /* If SIZE is -1 it means that somebody tried to allocate a temporary
659 of a variable size. */
664 align = BIGGEST_ALIGNMENT;
666 align = GET_MODE_ALIGNMENT (mode);
669 type = type_for_mode (mode, 0);
672 align = LOCAL_ALIGNMENT (type, align);
674 /* Try to find an available, already-allocated temporary of the proper
675 mode which meets the size and alignment requirements. Choose the
676 smallest one with the closest alignment. */
677 for (p = temp_slots; p; p = p->next)
678 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
680 && objects_must_conflict_p (p->type, type)
681 && (best_p == 0 || best_p->size > p->size
682 || (best_p->size == p->size && best_p->align > p->align)))
684 if (p->align == align && p->size == size)
692 /* Make our best, if any, the one to use. */
695 /* If there are enough aligned bytes left over, make them into a new
696 temp_slot so that the extra bytes don't get wasted. Do this only
697 for BLKmode slots, so that we can be sure of the alignment. */
698 if (GET_MODE (best_p->slot) == BLKmode)
700 int alignment = best_p->align / BITS_PER_UNIT;
701 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
703 if (best_p->size - rounded_size >= alignment)
705 p = (struct temp_slot *) xmalloc (sizeof (struct temp_slot));
706 p->in_use = p->addr_taken = 0;
707 p->size = best_p->size - rounded_size;
708 p->base_offset = best_p->base_offset + rounded_size;
709 p->full_size = best_p->full_size - rounded_size;
710 p->slot = gen_rtx_MEM (BLKmode,
711 plus_constant (XEXP (best_p->slot, 0),
713 p->align = best_p->align;
716 p->type = best_p->type;
717 p->next = temp_slots;
720 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
723 best_p->size = rounded_size;
724 best_p->full_size = rounded_size;
731 /* If we still didn't find one, make a new temporary. */
734 HOST_WIDE_INT frame_offset_old = frame_offset;
736 p = (struct temp_slot *) xmalloc (sizeof (struct temp_slot));
738 /* We are passing an explicit alignment request to assign_stack_local.
739 One side effect of that is assign_stack_local will not round SIZE
740 to ensure the frame offset remains suitably aligned.
742 So for requests which depended on the rounding of SIZE, we go ahead
743 and round it now. We also make sure ALIGNMENT is at least
744 BIGGEST_ALIGNMENT. */
745 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
747 p->slot = assign_stack_local (mode,
749 ? CEIL_ROUND (size, align / BITS_PER_UNIT)
755 /* The following slot size computation is necessary because we don't
756 know the actual size of the temporary slot until assign_stack_local
757 has performed all the frame alignment and size rounding for the
758 requested temporary. Note that extra space added for alignment
759 can be either above or below this stack slot depending on which
760 way the frame grows. We include the extra space if and only if it
761 is above this slot. */
762 #ifdef FRAME_GROWS_DOWNWARD
763 p->size = frame_offset_old - frame_offset;
768 /* Now define the fields used by combine_temp_slots. */
769 #ifdef FRAME_GROWS_DOWNWARD
770 p->base_offset = frame_offset;
771 p->full_size = frame_offset_old - frame_offset;
773 p->base_offset = frame_offset_old;
774 p->full_size = frame_offset - frame_offset_old;
777 p->next = temp_slots;
783 p->rtl_expr = seq_rtl_expr;
788 p->level = target_temp_slot_level;
793 p->level = var_temp_slot_level;
798 p->level = temp_slot_level;
802 /* We may be reusing an old slot, so clear any MEM flags that may have been
804 RTX_UNCHANGING_P (p->slot) = 0;
805 MEM_IN_STRUCT_P (p->slot) = 0;
806 MEM_SCALAR_P (p->slot) = 0;
807 MEM_VOLATILE_P (p->slot) = 0;
809 /* If we know the alias set for the memory that will be used, use
810 it. If there's no TYPE, then we don't know anything about the
811 alias set for the memory. */
812 set_mem_alias_set (p->slot, type ? get_alias_set (type) : 0);
814 /* If a type is specified, set the relevant flags. */
817 RTX_UNCHANGING_P (p->slot) = TYPE_READONLY (type);
818 MEM_VOLATILE_P (p->slot) = TYPE_VOLATILE (type);
819 MEM_SET_IN_STRUCT_P (p->slot, AGGREGATE_TYPE_P (type));
825 /* Allocate a temporary stack slot and record it for possible later
826 reuse. First three arguments are same as in preceding function. */
829 assign_stack_temp (mode, size, keep)
830 enum machine_mode mode;
834 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
837 /* Assign a temporary of given TYPE.
838 KEEP is as for assign_stack_temp.
839 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
840 it is 0 if a register is OK.
841 DONT_PROMOTE is 1 if we should not promote values in register
845 assign_temp (type, keep, memory_required, dont_promote)
849 int dont_promote ATTRIBUTE_UNUSED;
851 enum machine_mode mode = TYPE_MODE (type);
852 #ifndef PROMOTE_FOR_CALL_ONLY
853 int unsignedp = TREE_UNSIGNED (type);
856 if (mode == BLKmode || memory_required)
858 HOST_WIDE_INT size = int_size_in_bytes (type);
861 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
862 problems with allocating the stack space. */
866 /* Unfortunately, we don't yet know how to allocate variable-sized
867 temporaries. However, sometimes we have a fixed upper limit on
868 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
869 instead. This is the case for Chill variable-sized strings. */
870 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
871 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
872 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
873 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
875 tmp = assign_stack_temp_for_type (mode, size, keep, type);
879 #ifndef PROMOTE_FOR_CALL_ONLY
881 mode = promote_mode (type, mode, &unsignedp, 0);
884 return gen_reg_rtx (mode);
887 /* Combine temporary stack slots which are adjacent on the stack.
889 This allows for better use of already allocated stack space. This is only
890 done for BLKmode slots because we can be sure that we won't have alignment
891 problems in this case. */
894 combine_temp_slots ()
896 struct temp_slot *p, *q;
897 struct temp_slot *prev_p, *prev_q;
900 /* We can't combine slots, because the information about which slot
901 is in which alias set will be lost. */
902 if (flag_strict_aliasing)
905 /* If there are a lot of temp slots, don't do anything unless
906 high levels of optimizaton. */
907 if (! flag_expensive_optimizations)
908 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
909 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
912 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
916 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
917 for (q = p->next, prev_q = p; q; q = prev_q->next)
920 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
922 if (p->base_offset + p->full_size == q->base_offset)
924 /* Q comes after P; combine Q into P. */
926 p->full_size += q->full_size;
929 else if (q->base_offset + q->full_size == p->base_offset)
931 /* P comes after Q; combine P into Q. */
933 q->full_size += p->full_size;
938 /* Either delete Q or advance past it. */
941 prev_q->next = q->next;
947 /* Either delete P or advance past it. */
951 prev_p->next = p->next;
953 temp_slots = p->next;
960 /* Find the temp slot corresponding to the object at address X. */
962 static struct temp_slot *
963 find_temp_slot_from_address (x)
969 for (p = temp_slots; p; p = p->next)
974 else if (XEXP (p->slot, 0) == x
976 || (GET_CODE (x) == PLUS
977 && XEXP (x, 0) == virtual_stack_vars_rtx
978 && GET_CODE (XEXP (x, 1)) == CONST_INT
979 && INTVAL (XEXP (x, 1)) >= p->base_offset
980 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
983 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
984 for (next = p->address; next; next = XEXP (next, 1))
985 if (XEXP (next, 0) == x)
989 /* If we have a sum involving a register, see if it points to a temp
991 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == REG
992 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
994 else if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == REG
995 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
1001 /* Indicate that NEW is an alternate way of referring to the temp slot
1002 that previously was known by OLD. */
1005 update_temp_slot_address (old, new)
1008 struct temp_slot *p;
1010 if (rtx_equal_p (old, new))
1013 p = find_temp_slot_from_address (old);
1015 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
1016 is a register, see if one operand of the PLUS is a temporary
1017 location. If so, NEW points into it. Otherwise, if both OLD and
1018 NEW are a PLUS and if there is a register in common between them.
1019 If so, try a recursive call on those values. */
1022 if (GET_CODE (old) != PLUS)
1025 if (GET_CODE (new) == REG)
1027 update_temp_slot_address (XEXP (old, 0), new);
1028 update_temp_slot_address (XEXP (old, 1), new);
1031 else if (GET_CODE (new) != PLUS)
1034 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
1035 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
1036 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
1037 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
1038 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
1039 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
1040 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
1041 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
1046 /* Otherwise add an alias for the temp's address. */
1047 else if (p->address == 0)
1051 if (GET_CODE (p->address) != EXPR_LIST)
1052 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1054 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1058 /* If X could be a reference to a temporary slot, mark the fact that its
1059 address was taken. */
1062 mark_temp_addr_taken (x)
1065 struct temp_slot *p;
1070 /* If X is not in memory or is at a constant address, it cannot be in
1071 a temporary slot. */
1072 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1075 p = find_temp_slot_from_address (XEXP (x, 0));
1080 /* If X could be a reference to a temporary slot, mark that slot as
1081 belonging to the to one level higher than the current level. If X
1082 matched one of our slots, just mark that one. Otherwise, we can't
1083 easily predict which it is, so upgrade all of them. Kept slots
1084 need not be touched.
1086 This is called when an ({...}) construct occurs and a statement
1087 returns a value in memory. */
1090 preserve_temp_slots (x)
1093 struct temp_slot *p = 0;
1095 /* If there is no result, we still might have some objects whose address
1096 were taken, so we need to make sure they stay around. */
1099 for (p = temp_slots; p; p = p->next)
1100 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1106 /* If X is a register that is being used as a pointer, see if we have
1107 a temporary slot we know it points to. To be consistent with
1108 the code below, we really should preserve all non-kept slots
1109 if we can't find a match, but that seems to be much too costly. */
1110 if (GET_CODE (x) == REG && REG_POINTER (x))
1111 p = find_temp_slot_from_address (x);
1113 /* If X is not in memory or is at a constant address, it cannot be in
1114 a temporary slot, but it can contain something whose address was
1116 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1118 for (p = temp_slots; p; p = p->next)
1119 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1125 /* First see if we can find a match. */
1127 p = find_temp_slot_from_address (XEXP (x, 0));
1131 /* Move everything at our level whose address was taken to our new
1132 level in case we used its address. */
1133 struct temp_slot *q;
1135 if (p->level == temp_slot_level)
1137 for (q = temp_slots; q; q = q->next)
1138 if (q != p && q->addr_taken && q->level == p->level)
1147 /* Otherwise, preserve all non-kept slots at this level. */
1148 for (p = temp_slots; p; p = p->next)
1149 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1153 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1154 with that RTL_EXPR, promote it into a temporary slot at the present
1155 level so it will not be freed when we free slots made in the
1159 preserve_rtl_expr_result (x)
1162 struct temp_slot *p;
1164 /* If X is not in memory or is at a constant address, it cannot be in
1165 a temporary slot. */
1166 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1169 /* If we can find a match, move it to our level unless it is already at
1171 p = find_temp_slot_from_address (XEXP (x, 0));
1174 p->level = MIN (p->level, temp_slot_level);
1181 /* Free all temporaries used so far. This is normally called at the end
1182 of generating code for a statement. Don't free any temporaries
1183 currently in use for an RTL_EXPR that hasn't yet been emitted.
1184 We could eventually do better than this since it can be reused while
1185 generating the same RTL_EXPR, but this is complex and probably not
1191 struct temp_slot *p;
1193 for (p = temp_slots; p; p = p->next)
1194 if (p->in_use && p->level == temp_slot_level && ! p->keep
1195 && p->rtl_expr == 0)
1198 combine_temp_slots ();
1201 /* Free all temporary slots used in T, an RTL_EXPR node. */
1204 free_temps_for_rtl_expr (t)
1207 struct temp_slot *p;
1209 for (p = temp_slots; p; p = p->next)
1210 if (p->rtl_expr == t)
1212 /* If this slot is below the current TEMP_SLOT_LEVEL, then it
1213 needs to be preserved. This can happen if a temporary in
1214 the RTL_EXPR was addressed; preserve_temp_slots will move
1215 the temporary into a higher level. */
1216 if (temp_slot_level <= p->level)
1219 p->rtl_expr = NULL_TREE;
1222 combine_temp_slots ();
1225 /* Mark all temporaries ever allocated in this function as not suitable
1226 for reuse until the current level is exited. */
1229 mark_all_temps_used ()
1231 struct temp_slot *p;
1233 for (p = temp_slots; p; p = p->next)
1235 p->in_use = p->keep = 1;
1236 p->level = MIN (p->level, temp_slot_level);
1240 /* Push deeper into the nesting level for stack temporaries. */
1248 /* Likewise, but save the new level as the place to allocate variables
1253 push_temp_slots_for_block ()
1257 var_temp_slot_level = temp_slot_level;
1260 /* Likewise, but save the new level as the place to allocate temporaries
1261 for TARGET_EXPRs. */
1264 push_temp_slots_for_target ()
1268 target_temp_slot_level = temp_slot_level;
1271 /* Set and get the value of target_temp_slot_level. The only
1272 permitted use of these functions is to save and restore this value. */
1275 get_target_temp_slot_level ()
1277 return target_temp_slot_level;
1281 set_target_temp_slot_level (level)
1284 target_temp_slot_level = level;
1288 /* Pop a temporary nesting level. All slots in use in the current level
1294 struct temp_slot *p;
1296 for (p = temp_slots; p; p = p->next)
1297 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1300 combine_temp_slots ();
1305 /* Initialize temporary slots. */
1310 /* We have not allocated any temporaries yet. */
1312 temp_slot_level = 0;
1313 var_temp_slot_level = 0;
1314 target_temp_slot_level = 0;
1317 /* Retroactively move an auto variable from a register to a stack slot.
1318 This is done when an address-reference to the variable is seen. */
1321 put_var_into_stack (decl)
1325 enum machine_mode promoted_mode, decl_mode;
1326 struct function *function = 0;
1328 int can_use_addressof;
1329 int volatilep = TREE_CODE (decl) != SAVE_EXPR && TREE_THIS_VOLATILE (decl);
1330 int usedp = (TREE_USED (decl)
1331 || (TREE_CODE (decl) != SAVE_EXPR && DECL_INITIAL (decl) != 0));
1333 context = decl_function_context (decl);
1335 /* Get the current rtl used for this object and its original mode. */
1336 reg = (TREE_CODE (decl) == SAVE_EXPR
1337 ? SAVE_EXPR_RTL (decl)
1338 : DECL_RTL_IF_SET (decl));
1340 /* No need to do anything if decl has no rtx yet
1341 since in that case caller is setting TREE_ADDRESSABLE
1342 and a stack slot will be assigned when the rtl is made. */
1346 /* Get the declared mode for this object. */
1347 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1348 : DECL_MODE (decl));
1349 /* Get the mode it's actually stored in. */
1350 promoted_mode = GET_MODE (reg);
1352 /* If this variable comes from an outer function,
1353 find that function's saved context. */
1354 if (context != current_function_decl && context != inline_function_decl)
1355 for (function = outer_function_chain; function; function = function->next)
1356 if (function->decl == context)
1359 /* If this is a variable-size object with a pseudo to address it,
1360 put that pseudo into the stack, if the var is nonlocal. */
1361 if (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl)
1362 && GET_CODE (reg) == MEM
1363 && GET_CODE (XEXP (reg, 0)) == REG
1364 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1366 reg = XEXP (reg, 0);
1367 decl_mode = promoted_mode = GET_MODE (reg);
1373 /* FIXME make it work for promoted modes too */
1374 && decl_mode == promoted_mode
1375 #ifdef NON_SAVING_SETJMP
1376 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1380 /* If we can't use ADDRESSOF, make sure we see through one we already
1382 if (! can_use_addressof && GET_CODE (reg) == MEM
1383 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1384 reg = XEXP (XEXP (reg, 0), 0);
1386 /* Now we should have a value that resides in one or more pseudo regs. */
1388 if (GET_CODE (reg) == REG)
1390 /* If this variable lives in the current function and we don't need
1391 to put things in the stack for the sake of setjmp, try to keep it
1392 in a register until we know we actually need the address. */
1393 if (can_use_addressof)
1394 gen_mem_addressof (reg, decl);
1396 put_reg_into_stack (function, reg, TREE_TYPE (decl), promoted_mode,
1397 decl_mode, volatilep, 0, usedp, 0);
1399 else if (GET_CODE (reg) == CONCAT)
1401 /* A CONCAT contains two pseudos; put them both in the stack.
1402 We do it so they end up consecutive.
1403 We fixup references to the parts only after we fixup references
1404 to the whole CONCAT, lest we do double fixups for the latter
1406 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1407 tree part_type = type_for_mode (part_mode, 0);
1408 rtx lopart = XEXP (reg, 0);
1409 rtx hipart = XEXP (reg, 1);
1410 #ifdef FRAME_GROWS_DOWNWARD
1411 /* Since part 0 should have a lower address, do it second. */
1412 put_reg_into_stack (function, hipart, part_type, part_mode,
1413 part_mode, volatilep, 0, 0, 0);
1414 put_reg_into_stack (function, lopart, part_type, part_mode,
1415 part_mode, volatilep, 0, 0, 0);
1417 put_reg_into_stack (function, lopart, part_type, part_mode,
1418 part_mode, volatilep, 0, 0, 0);
1419 put_reg_into_stack (function, hipart, part_type, part_mode,
1420 part_mode, volatilep, 0, 0, 0);
1423 /* Change the CONCAT into a combined MEM for both parts. */
1424 PUT_CODE (reg, MEM);
1425 set_mem_attributes (reg, decl, 1);
1427 /* The two parts are in memory order already.
1428 Use the lower parts address as ours. */
1429 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1430 /* Prevent sharing of rtl that might lose. */
1431 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1432 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1435 schedule_fixup_var_refs (function, reg, TREE_TYPE (decl),
1437 schedule_fixup_var_refs (function, lopart, part_type, part_mode, 0);
1438 schedule_fixup_var_refs (function, hipart, part_type, part_mode, 0);
1444 if (current_function_check_memory_usage)
1445 emit_library_call (chkr_set_right_libfunc, LCT_CONST_MAKE_BLOCK, VOIDmode,
1446 3, XEXP (reg, 0), Pmode,
1447 GEN_INT (GET_MODE_SIZE (GET_MODE (reg))),
1448 TYPE_MODE (sizetype),
1449 GEN_INT (MEMORY_USE_RW),
1450 TYPE_MODE (integer_type_node));
1453 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1454 into the stack frame of FUNCTION (0 means the current function).
1455 DECL_MODE is the machine mode of the user-level data type.
1456 PROMOTED_MODE is the machine mode of the register.
1457 VOLATILE_P is nonzero if this is for a "volatile" decl.
1458 USED_P is nonzero if this reg might have already been used in an insn. */
1461 put_reg_into_stack (function, reg, type, promoted_mode, decl_mode, volatile_p,
1462 original_regno, used_p, ht)
1463 struct function *function;
1466 enum machine_mode promoted_mode, decl_mode;
1468 unsigned int original_regno;
1470 struct hash_table *ht;
1472 struct function *func = function ? function : cfun;
1474 unsigned int regno = original_regno;
1477 regno = REGNO (reg);
1479 if (regno < func->x_max_parm_reg)
1480 new = func->x_parm_reg_stack_loc[regno];
1483 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode), 0, func);
1485 PUT_CODE (reg, MEM);
1486 PUT_MODE (reg, decl_mode);
1487 XEXP (reg, 0) = XEXP (new, 0);
1488 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1489 MEM_VOLATILE_P (reg) = volatile_p;
1491 /* If this is a memory ref that contains aggregate components,
1492 mark it as such for cse and loop optimize. If we are reusing a
1493 previously generated stack slot, then we need to copy the bit in
1494 case it was set for other reasons. For instance, it is set for
1495 __builtin_va_alist. */
1498 MEM_SET_IN_STRUCT_P (reg,
1499 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1500 set_mem_alias_set (reg, get_alias_set (type));
1503 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht);
1506 /* Make sure that all refs to the variable, previously made
1507 when it was a register, are fixed up to be valid again.
1508 See function above for meaning of arguments. */
1511 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht)
1512 struct function *function;
1515 enum machine_mode promoted_mode;
1516 struct hash_table *ht;
1518 int unsigned_p = type ? TREE_UNSIGNED (type) : 0;
1522 struct var_refs_queue *temp;
1525 = (struct var_refs_queue *) xmalloc (sizeof (struct var_refs_queue));
1526 temp->modified = reg;
1527 temp->promoted_mode = promoted_mode;
1528 temp->unsignedp = unsigned_p;
1529 temp->next = function->fixup_var_refs_queue;
1530 function->fixup_var_refs_queue = temp;
1533 /* Variable is local; fix it up now. */
1534 fixup_var_refs (reg, promoted_mode, unsigned_p, ht);
1538 fixup_var_refs (var, promoted_mode, unsignedp, ht)
1540 enum machine_mode promoted_mode;
1542 struct hash_table *ht;
1545 rtx first_insn = get_insns ();
1546 struct sequence_stack *stack = seq_stack;
1547 tree rtl_exps = rtl_expr_chain;
1549 /* If there's a hash table, it must record all uses of VAR. */
1554 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp);
1558 fixup_var_refs_insns (first_insn, var, promoted_mode, unsignedp,
1561 /* Scan all pending sequences too. */
1562 for (; stack; stack = stack->next)
1564 push_to_full_sequence (stack->first, stack->last);
1565 fixup_var_refs_insns (stack->first, var, promoted_mode, unsignedp,
1567 /* Update remembered end of sequence
1568 in case we added an insn at the end. */
1569 stack->last = get_last_insn ();
1573 /* Scan all waiting RTL_EXPRs too. */
1574 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1576 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1577 if (seq != const0_rtx && seq != 0)
1579 push_to_sequence (seq);
1580 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0);
1586 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1587 some part of an insn. Return a struct fixup_replacement whose OLD
1588 value is equal to X. Allocate a new structure if no such entry exists. */
1590 static struct fixup_replacement *
1591 find_fixup_replacement (replacements, x)
1592 struct fixup_replacement **replacements;
1595 struct fixup_replacement *p;
1597 /* See if we have already replaced this. */
1598 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1603 p = (struct fixup_replacement *) xmalloc (sizeof (struct fixup_replacement));
1606 p->next = *replacements;
1613 /* Scan the insn-chain starting with INSN for refs to VAR
1614 and fix them up. TOPLEVEL is nonzero if this chain is the
1615 main chain of insns for the current function. */
1618 fixup_var_refs_insns (insn, var, promoted_mode, unsignedp, toplevel)
1621 enum machine_mode promoted_mode;
1627 /* fixup_var_refs_insn might modify insn, so save its next
1629 rtx next = NEXT_INSN (insn);
1631 /* CALL_PLACEHOLDERs are special; we have to switch into each of
1632 the three sequences they (potentially) contain, and process
1633 them recursively. The CALL_INSN itself is not interesting. */
1635 if (GET_CODE (insn) == CALL_INSN
1636 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
1640 /* Look at the Normal call, sibling call and tail recursion
1641 sequences attached to the CALL_PLACEHOLDER. */
1642 for (i = 0; i < 3; i++)
1644 rtx seq = XEXP (PATTERN (insn), i);
1647 push_to_sequence (seq);
1648 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0);
1649 XEXP (PATTERN (insn), i) = get_insns ();
1655 else if (INSN_P (insn))
1656 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel);
1662 /* Look up the insns which reference VAR in HT and fix them up. Other
1663 arguments are the same as fixup_var_refs_insns.
1665 N.B. No need for special processing of CALL_PLACEHOLDERs here,
1666 because the hash table will point straight to the interesting insn
1667 (inside the CALL_PLACEHOLDER). */
1669 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp)
1670 struct hash_table *ht;
1672 enum machine_mode promoted_mode;
1675 struct insns_for_mem_entry *ime = (struct insns_for_mem_entry *)
1676 hash_lookup (ht, var, /*create=*/0, /*copy=*/0);
1677 rtx insn_list = ime->insns;
1681 rtx insn = XEXP (insn_list, 0);
1684 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, 1);
1686 insn_list = XEXP (insn_list, 1);
1691 /* Per-insn processing by fixup_var_refs_insns(_with_hash). INSN is
1692 the insn under examination, VAR is the variable to fix up
1693 references to, PROMOTED_MODE and UNSIGNEDP describe VAR, and
1694 TOPLEVEL is nonzero if this is the main insn chain for this
1697 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel)
1700 enum machine_mode promoted_mode;
1705 rtx set, prev, prev_set;
1708 /* Remember the notes in case we delete the insn. */
1709 note = REG_NOTES (insn);
1711 /* If this is a CLOBBER of VAR, delete it.
1713 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1714 and REG_RETVAL notes too. */
1715 if (GET_CODE (PATTERN (insn)) == CLOBBER
1716 && (XEXP (PATTERN (insn), 0) == var
1717 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1718 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1719 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1721 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1722 /* The REG_LIBCALL note will go away since we are going to
1723 turn INSN into a NOTE, so just delete the
1724 corresponding REG_RETVAL note. */
1725 remove_note (XEXP (note, 0),
1726 find_reg_note (XEXP (note, 0), REG_RETVAL,
1729 /* In unoptimized compilation, we shouldn't call delete_insn
1730 except in jump.c doing warnings. */
1731 PUT_CODE (insn, NOTE);
1732 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1733 NOTE_SOURCE_FILE (insn) = 0;
1736 /* The insn to load VAR from a home in the arglist
1737 is now a no-op. When we see it, just delete it.
1738 Similarly if this is storing VAR from a register from which
1739 it was loaded in the previous insn. This will occur
1740 when an ADDRESSOF was made for an arglist slot. */
1742 && (set = single_set (insn)) != 0
1743 && SET_DEST (set) == var
1744 /* If this represents the result of an insn group,
1745 don't delete the insn. */
1746 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1747 && (rtx_equal_p (SET_SRC (set), var)
1748 || (GET_CODE (SET_SRC (set)) == REG
1749 && (prev = prev_nonnote_insn (insn)) != 0
1750 && (prev_set = single_set (prev)) != 0
1751 && SET_DEST (prev_set) == SET_SRC (set)
1752 && rtx_equal_p (SET_SRC (prev_set), var))))
1754 /* In unoptimized compilation, we shouldn't call delete_insn
1755 except in jump.c doing warnings. */
1756 PUT_CODE (insn, NOTE);
1757 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1758 NOTE_SOURCE_FILE (insn) = 0;
1762 struct fixup_replacement *replacements = 0;
1763 rtx next_insn = NEXT_INSN (insn);
1765 if (SMALL_REGISTER_CLASSES)
1767 /* If the insn that copies the results of a CALL_INSN
1768 into a pseudo now references VAR, we have to use an
1769 intermediate pseudo since we want the life of the
1770 return value register to be only a single insn.
1772 If we don't use an intermediate pseudo, such things as
1773 address computations to make the address of VAR valid
1774 if it is not can be placed between the CALL_INSN and INSN.
1776 To make sure this doesn't happen, we record the destination
1777 of the CALL_INSN and see if the next insn uses both that
1780 if (call_dest != 0 && GET_CODE (insn) == INSN
1781 && reg_mentioned_p (var, PATTERN (insn))
1782 && reg_mentioned_p (call_dest, PATTERN (insn)))
1784 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1786 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1788 PATTERN (insn) = replace_rtx (PATTERN (insn),
1792 if (GET_CODE (insn) == CALL_INSN
1793 && GET_CODE (PATTERN (insn)) == SET)
1794 call_dest = SET_DEST (PATTERN (insn));
1795 else if (GET_CODE (insn) == CALL_INSN
1796 && GET_CODE (PATTERN (insn)) == PARALLEL
1797 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1798 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1803 /* See if we have to do anything to INSN now that VAR is in
1804 memory. If it needs to be loaded into a pseudo, use a single
1805 pseudo for the entire insn in case there is a MATCH_DUP
1806 between two operands. We pass a pointer to the head of
1807 a list of struct fixup_replacements. If fixup_var_refs_1
1808 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1809 it will record them in this list.
1811 If it allocated a pseudo for any replacement, we copy into
1814 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1817 /* If this is last_parm_insn, and any instructions were output
1818 after it to fix it up, then we must set last_parm_insn to
1819 the last such instruction emitted. */
1820 if (insn == last_parm_insn)
1821 last_parm_insn = PREV_INSN (next_insn);
1823 while (replacements)
1825 struct fixup_replacement *next;
1827 if (GET_CODE (replacements->new) == REG)
1832 /* OLD might be a (subreg (mem)). */
1833 if (GET_CODE (replacements->old) == SUBREG)
1835 = fixup_memory_subreg (replacements->old, insn, 0);
1838 = fixup_stack_1 (replacements->old, insn);
1840 insert_before = insn;
1842 /* If we are changing the mode, do a conversion.
1843 This might be wasteful, but combine.c will
1844 eliminate much of the waste. */
1846 if (GET_MODE (replacements->new)
1847 != GET_MODE (replacements->old))
1850 convert_move (replacements->new,
1851 replacements->old, unsignedp);
1852 seq = gen_sequence ();
1856 seq = gen_move_insn (replacements->new,
1859 emit_insn_before (seq, insert_before);
1862 next = replacements->next;
1863 free (replacements);
1864 replacements = next;
1868 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1869 But don't touch other insns referred to by reg-notes;
1870 we will get them elsewhere. */
1873 if (GET_CODE (note) != INSN_LIST)
1875 = walk_fixup_memory_subreg (XEXP (note, 0), insn, 1);
1876 note = XEXP (note, 1);
1880 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1881 See if the rtx expression at *LOC in INSN needs to be changed.
1883 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1884 contain a list of original rtx's and replacements. If we find that we need
1885 to modify this insn by replacing a memory reference with a pseudo or by
1886 making a new MEM to implement a SUBREG, we consult that list to see if
1887 we have already chosen a replacement. If none has already been allocated,
1888 we allocate it and update the list. fixup_var_refs_insn will copy VAR
1889 or the SUBREG, as appropriate, to the pseudo. */
1892 fixup_var_refs_1 (var, promoted_mode, loc, insn, replacements)
1894 enum machine_mode promoted_mode;
1897 struct fixup_replacement **replacements;
1900 register rtx x = *loc;
1901 RTX_CODE code = GET_CODE (x);
1902 register const char *fmt;
1903 register rtx tem, tem1;
1904 struct fixup_replacement *replacement;
1909 if (XEXP (x, 0) == var)
1911 /* Prevent sharing of rtl that might lose. */
1912 rtx sub = copy_rtx (XEXP (var, 0));
1914 if (! validate_change (insn, loc, sub, 0))
1916 rtx y = gen_reg_rtx (GET_MODE (sub));
1919 /* We should be able to replace with a register or all is lost.
1920 Note that we can't use validate_change to verify this, since
1921 we're not caring for replacing all dups simultaneously. */
1922 if (! validate_replace_rtx (*loc, y, insn))
1925 /* Careful! First try to recognize a direct move of the
1926 value, mimicking how things are done in gen_reload wrt
1927 PLUS. Consider what happens when insn is a conditional
1928 move instruction and addsi3 clobbers flags. */
1931 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1932 seq = gen_sequence ();
1935 if (recog_memoized (new_insn) < 0)
1937 /* That failed. Fall back on force_operand and hope. */
1940 sub = force_operand (sub, y);
1942 emit_insn (gen_move_insn (y, sub));
1943 seq = gen_sequence ();
1948 /* Don't separate setter from user. */
1949 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1950 insn = PREV_INSN (insn);
1953 emit_insn_before (seq, insn);
1961 /* If we already have a replacement, use it. Otherwise,
1962 try to fix up this address in case it is invalid. */
1964 replacement = find_fixup_replacement (replacements, var);
1965 if (replacement->new)
1967 *loc = replacement->new;
1971 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1973 /* Unless we are forcing memory to register or we changed the mode,
1974 we can leave things the way they are if the insn is valid. */
1976 INSN_CODE (insn) = -1;
1977 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1978 && recog_memoized (insn) >= 0)
1981 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1985 /* If X contains VAR, we need to unshare it here so that we update
1986 each occurrence separately. But all identical MEMs in one insn
1987 must be replaced with the same rtx because of the possibility of
1990 if (reg_mentioned_p (var, x))
1992 replacement = find_fixup_replacement (replacements, x);
1993 if (replacement->new == 0)
1994 replacement->new = copy_most_rtx (x, var);
1996 *loc = x = replacement->new;
1997 code = GET_CODE (x);
2013 /* Note that in some cases those types of expressions are altered
2014 by optimize_bit_field, and do not survive to get here. */
2015 if (XEXP (x, 0) == var
2016 || (GET_CODE (XEXP (x, 0)) == SUBREG
2017 && SUBREG_REG (XEXP (x, 0)) == var))
2019 /* Get TEM as a valid MEM in the mode presently in the insn.
2021 We don't worry about the possibility of MATCH_DUP here; it
2022 is highly unlikely and would be tricky to handle. */
2025 if (GET_CODE (tem) == SUBREG)
2027 if (GET_MODE_BITSIZE (GET_MODE (tem))
2028 > GET_MODE_BITSIZE (GET_MODE (var)))
2030 replacement = find_fixup_replacement (replacements, var);
2031 if (replacement->new == 0)
2032 replacement->new = gen_reg_rtx (GET_MODE (var));
2033 SUBREG_REG (tem) = replacement->new;
2035 /* The following code works only if we have a MEM, so we
2036 need to handle the subreg here. We directly substitute
2037 it assuming that a subreg must be OK here. We already
2038 scheduled a replacement to copy the mem into the
2044 tem = fixup_memory_subreg (tem, insn, 0);
2047 tem = fixup_stack_1 (tem, insn);
2049 /* Unless we want to load from memory, get TEM into the proper mode
2050 for an extract from memory. This can only be done if the
2051 extract is at a constant position and length. */
2053 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
2054 && GET_CODE (XEXP (x, 2)) == CONST_INT
2055 && ! mode_dependent_address_p (XEXP (tem, 0))
2056 && ! MEM_VOLATILE_P (tem))
2058 enum machine_mode wanted_mode = VOIDmode;
2059 enum machine_mode is_mode = GET_MODE (tem);
2060 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
2063 if (GET_CODE (x) == ZERO_EXTRACT)
2066 = insn_data[(int) CODE_FOR_extzv].operand[1].mode;
2067 if (wanted_mode == VOIDmode)
2068 wanted_mode = word_mode;
2072 if (GET_CODE (x) == SIGN_EXTRACT)
2074 wanted_mode = insn_data[(int) CODE_FOR_extv].operand[1].mode;
2075 if (wanted_mode == VOIDmode)
2076 wanted_mode = word_mode;
2079 /* If we have a narrower mode, we can do something. */
2080 if (wanted_mode != VOIDmode
2081 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2083 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2084 rtx old_pos = XEXP (x, 2);
2087 /* If the bytes and bits are counted differently, we
2088 must adjust the offset. */
2089 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2090 offset = (GET_MODE_SIZE (is_mode)
2091 - GET_MODE_SIZE (wanted_mode) - offset);
2093 pos %= GET_MODE_BITSIZE (wanted_mode);
2095 newmem = adjust_address_nv (tem, wanted_mode, offset);
2097 /* Make the change and see if the insn remains valid. */
2098 INSN_CODE (insn) = -1;
2099 XEXP (x, 0) = newmem;
2100 XEXP (x, 2) = GEN_INT (pos);
2102 if (recog_memoized (insn) >= 0)
2105 /* Otherwise, restore old position. XEXP (x, 0) will be
2107 XEXP (x, 2) = old_pos;
2111 /* If we get here, the bitfield extract insn can't accept a memory
2112 reference. Copy the input into a register. */
2114 tem1 = gen_reg_rtx (GET_MODE (tem));
2115 emit_insn_before (gen_move_insn (tem1, tem), insn);
2122 if (SUBREG_REG (x) == var)
2124 /* If this is a special SUBREG made because VAR was promoted
2125 from a wider mode, replace it with VAR and call ourself
2126 recursively, this time saying that the object previously
2127 had its current mode (by virtue of the SUBREG). */
2129 if (SUBREG_PROMOTED_VAR_P (x))
2132 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements);
2136 /* If this SUBREG makes VAR wider, it has become a paradoxical
2137 SUBREG with VAR in memory, but these aren't allowed at this
2138 stage of the compilation. So load VAR into a pseudo and take
2139 a SUBREG of that pseudo. */
2140 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2142 replacement = find_fixup_replacement (replacements, var);
2143 if (replacement->new == 0)
2144 replacement->new = gen_reg_rtx (promoted_mode);
2145 SUBREG_REG (x) = replacement->new;
2149 /* See if we have already found a replacement for this SUBREG.
2150 If so, use it. Otherwise, make a MEM and see if the insn
2151 is recognized. If not, or if we should force MEM into a register,
2152 make a pseudo for this SUBREG. */
2153 replacement = find_fixup_replacement (replacements, x);
2154 if (replacement->new)
2156 *loc = replacement->new;
2160 replacement->new = *loc = fixup_memory_subreg (x, insn, 0);
2162 INSN_CODE (insn) = -1;
2163 if (! flag_force_mem && recog_memoized (insn) >= 0)
2166 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2172 /* First do special simplification of bit-field references. */
2173 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2174 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2175 optimize_bit_field (x, insn, 0);
2176 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2177 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2178 optimize_bit_field (x, insn, 0);
2180 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2181 into a register and then store it back out. */
2182 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2183 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2184 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2185 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2186 > GET_MODE_SIZE (GET_MODE (var))))
2188 replacement = find_fixup_replacement (replacements, var);
2189 if (replacement->new == 0)
2190 replacement->new = gen_reg_rtx (GET_MODE (var));
2192 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2193 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2196 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2197 insn into a pseudo and store the low part of the pseudo into VAR. */
2198 if (GET_CODE (SET_DEST (x)) == SUBREG
2199 && SUBREG_REG (SET_DEST (x)) == var
2200 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2201 > GET_MODE_SIZE (GET_MODE (var))))
2203 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2204 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2211 rtx dest = SET_DEST (x);
2212 rtx src = SET_SRC (x);
2214 rtx outerdest = dest;
2217 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2218 || GET_CODE (dest) == SIGN_EXTRACT
2219 || GET_CODE (dest) == ZERO_EXTRACT)
2220 dest = XEXP (dest, 0);
2222 if (GET_CODE (src) == SUBREG)
2223 src = SUBREG_REG (src);
2225 /* If VAR does not appear at the top level of the SET
2226 just scan the lower levels of the tree. */
2228 if (src != var && dest != var)
2231 /* We will need to rerecognize this insn. */
2232 INSN_CODE (insn) = -1;
2235 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var)
2237 /* Since this case will return, ensure we fixup all the
2239 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2240 insn, replacements);
2241 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2242 insn, replacements);
2243 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2244 insn, replacements);
2246 tem = XEXP (outerdest, 0);
2248 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2249 that may appear inside a ZERO_EXTRACT.
2250 This was legitimate when the MEM was a REG. */
2251 if (GET_CODE (tem) == SUBREG
2252 && SUBREG_REG (tem) == var)
2253 tem = fixup_memory_subreg (tem, insn, 0);
2255 tem = fixup_stack_1 (tem, insn);
2257 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2258 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2259 && ! mode_dependent_address_p (XEXP (tem, 0))
2260 && ! MEM_VOLATILE_P (tem))
2262 enum machine_mode wanted_mode;
2263 enum machine_mode is_mode = GET_MODE (tem);
2264 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2266 wanted_mode = insn_data[(int) CODE_FOR_insv].operand[0].mode;
2267 if (wanted_mode == VOIDmode)
2268 wanted_mode = word_mode;
2270 /* If we have a narrower mode, we can do something. */
2271 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2273 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2274 rtx old_pos = XEXP (outerdest, 2);
2277 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2278 offset = (GET_MODE_SIZE (is_mode)
2279 - GET_MODE_SIZE (wanted_mode) - offset);
2281 pos %= GET_MODE_BITSIZE (wanted_mode);
2283 newmem = adjust_address_nv (tem, wanted_mode, offset);
2285 /* Make the change and see if the insn remains valid. */
2286 INSN_CODE (insn) = -1;
2287 XEXP (outerdest, 0) = newmem;
2288 XEXP (outerdest, 2) = GEN_INT (pos);
2290 if (recog_memoized (insn) >= 0)
2293 /* Otherwise, restore old position. XEXP (x, 0) will be
2295 XEXP (outerdest, 2) = old_pos;
2299 /* If we get here, the bit-field store doesn't allow memory
2300 or isn't located at a constant position. Load the value into
2301 a register, do the store, and put it back into memory. */
2303 tem1 = gen_reg_rtx (GET_MODE (tem));
2304 emit_insn_before (gen_move_insn (tem1, tem), insn);
2305 emit_insn_after (gen_move_insn (tem, tem1), insn);
2306 XEXP (outerdest, 0) = tem1;
2311 /* STRICT_LOW_PART is a no-op on memory references
2312 and it can cause combinations to be unrecognizable,
2315 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2316 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2318 /* A valid insn to copy VAR into or out of a register
2319 must be left alone, to avoid an infinite loop here.
2320 If the reference to VAR is by a subreg, fix that up,
2321 since SUBREG is not valid for a memref.
2322 Also fix up the address of the stack slot.
2324 Note that we must not try to recognize the insn until
2325 after we know that we have valid addresses and no
2326 (subreg (mem ...) ...) constructs, since these interfere
2327 with determining the validity of the insn. */
2329 if ((SET_SRC (x) == var
2330 || (GET_CODE (SET_SRC (x)) == SUBREG
2331 && SUBREG_REG (SET_SRC (x)) == var))
2332 && (GET_CODE (SET_DEST (x)) == REG
2333 || (GET_CODE (SET_DEST (x)) == SUBREG
2334 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2335 && GET_MODE (var) == promoted_mode
2336 && x == single_set (insn))
2340 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2341 if (replacement->new)
2342 SET_SRC (x) = replacement->new;
2343 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2344 SET_SRC (x) = replacement->new
2345 = fixup_memory_subreg (SET_SRC (x), insn, 0);
2347 SET_SRC (x) = replacement->new
2348 = fixup_stack_1 (SET_SRC (x), insn);
2350 if (recog_memoized (insn) >= 0)
2353 /* INSN is not valid, but we know that we want to
2354 copy SET_SRC (x) to SET_DEST (x) in some way. So
2355 we generate the move and see whether it requires more
2356 than one insn. If it does, we emit those insns and
2357 delete INSN. Otherwise, we an just replace the pattern
2358 of INSN; we have already verified above that INSN has
2359 no other function that to do X. */
2361 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2362 if (GET_CODE (pat) == SEQUENCE)
2364 last = emit_insn_before (pat, insn);
2366 /* INSN might have REG_RETVAL or other important notes, so
2367 we need to store the pattern of the last insn in the
2368 sequence into INSN similarly to the normal case. LAST
2369 should not have REG_NOTES, but we allow them if INSN has
2371 if (REG_NOTES (last) && REG_NOTES (insn))
2373 if (REG_NOTES (last))
2374 REG_NOTES (insn) = REG_NOTES (last);
2375 PATTERN (insn) = PATTERN (last);
2377 PUT_CODE (last, NOTE);
2378 NOTE_LINE_NUMBER (last) = NOTE_INSN_DELETED;
2379 NOTE_SOURCE_FILE (last) = 0;
2382 PATTERN (insn) = pat;
2387 if ((SET_DEST (x) == var
2388 || (GET_CODE (SET_DEST (x)) == SUBREG
2389 && SUBREG_REG (SET_DEST (x)) == var))
2390 && (GET_CODE (SET_SRC (x)) == REG
2391 || (GET_CODE (SET_SRC (x)) == SUBREG
2392 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2393 && GET_MODE (var) == promoted_mode
2394 && x == single_set (insn))
2398 if (GET_CODE (SET_DEST (x)) == SUBREG)
2399 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn, 0);
2401 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2403 if (recog_memoized (insn) >= 0)
2406 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2407 if (GET_CODE (pat) == SEQUENCE)
2409 last = emit_insn_before (pat, insn);
2411 /* INSN might have REG_RETVAL or other important notes, so
2412 we need to store the pattern of the last insn in the
2413 sequence into INSN similarly to the normal case. LAST
2414 should not have REG_NOTES, but we allow them if INSN has
2416 if (REG_NOTES (last) && REG_NOTES (insn))
2418 if (REG_NOTES (last))
2419 REG_NOTES (insn) = REG_NOTES (last);
2420 PATTERN (insn) = PATTERN (last);
2422 PUT_CODE (last, NOTE);
2423 NOTE_LINE_NUMBER (last) = NOTE_INSN_DELETED;
2424 NOTE_SOURCE_FILE (last) = 0;
2427 PATTERN (insn) = pat;
2432 /* Otherwise, storing into VAR must be handled specially
2433 by storing into a temporary and copying that into VAR
2434 with a new insn after this one. Note that this case
2435 will be used when storing into a promoted scalar since
2436 the insn will now have different modes on the input
2437 and output and hence will be invalid (except for the case
2438 of setting it to a constant, which does not need any
2439 change if it is valid). We generate extra code in that case,
2440 but combine.c will eliminate it. */
2445 rtx fixeddest = SET_DEST (x);
2447 /* STRICT_LOW_PART can be discarded, around a MEM. */
2448 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2449 fixeddest = XEXP (fixeddest, 0);
2450 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2451 if (GET_CODE (fixeddest) == SUBREG)
2453 fixeddest = fixup_memory_subreg (fixeddest, insn, 0);
2454 promoted_mode = GET_MODE (fixeddest);
2457 fixeddest = fixup_stack_1 (fixeddest, insn);
2459 temp = gen_reg_rtx (promoted_mode);
2461 emit_insn_after (gen_move_insn (fixeddest,
2462 gen_lowpart (GET_MODE (fixeddest),
2466 SET_DEST (x) = temp;
2474 /* Nothing special about this RTX; fix its operands. */
2476 fmt = GET_RTX_FORMAT (code);
2477 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2480 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements);
2481 else if (fmt[i] == 'E')
2484 for (j = 0; j < XVECLEN (x, i); j++)
2485 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2486 insn, replacements);
2491 /* Given X, an rtx of the form (SUBREG:m1 (MEM:m2 addr)),
2492 return an rtx (MEM:m1 newaddr) which is equivalent.
2493 If any insns must be emitted to compute NEWADDR, put them before INSN.
2495 UNCRITICAL nonzero means accept paradoxical subregs.
2496 This is used for subregs found inside REG_NOTES. */
2499 fixup_memory_subreg (x, insn, uncritical)
2504 int offset = SUBREG_BYTE (x);
2505 rtx addr = XEXP (SUBREG_REG (x), 0);
2506 enum machine_mode mode = GET_MODE (x);
2509 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2510 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))
2514 if (!flag_force_addr
2515 && memory_address_p (mode, plus_constant (addr, offset)))
2516 /* Shortcut if no insns need be emitted. */
2517 return adjust_address (SUBREG_REG (x), mode, offset);
2520 result = adjust_address (SUBREG_REG (x), mode, offset);
2521 emit_insn_before (gen_sequence (), insn);
2526 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2527 Replace subexpressions of X in place.
2528 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2529 Otherwise return X, with its contents possibly altered.
2531 If any insns must be emitted to compute NEWADDR, put them before INSN.
2533 UNCRITICAL is as in fixup_memory_subreg. */
2536 walk_fixup_memory_subreg (x, insn, uncritical)
2541 register enum rtx_code code;
2542 register const char *fmt;
2548 code = GET_CODE (x);
2550 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2551 return fixup_memory_subreg (x, insn, uncritical);
2553 /* Nothing special about this RTX; fix its operands. */
2555 fmt = GET_RTX_FORMAT (code);
2556 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2559 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn, uncritical);
2560 else if (fmt[i] == 'E')
2563 for (j = 0; j < XVECLEN (x, i); j++)
2565 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn, uncritical);
2571 /* For each memory ref within X, if it refers to a stack slot
2572 with an out of range displacement, put the address in a temp register
2573 (emitting new insns before INSN to load these registers)
2574 and alter the memory ref to use that register.
2575 Replace each such MEM rtx with a copy, to avoid clobberage. */
2578 fixup_stack_1 (x, insn)
2583 register RTX_CODE code = GET_CODE (x);
2584 register const char *fmt;
2588 register rtx ad = XEXP (x, 0);
2589 /* If we have address of a stack slot but it's not valid
2590 (displacement is too large), compute the sum in a register. */
2591 if (GET_CODE (ad) == PLUS
2592 && GET_CODE (XEXP (ad, 0)) == REG
2593 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2594 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2595 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2596 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2597 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2599 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2600 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2601 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2602 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2605 if (memory_address_p (GET_MODE (x), ad))
2609 temp = copy_to_reg (ad);
2610 seq = gen_sequence ();
2612 emit_insn_before (seq, insn);
2613 return replace_equiv_address (x, temp);
2618 fmt = GET_RTX_FORMAT (code);
2619 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2622 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2623 else if (fmt[i] == 'E')
2626 for (j = 0; j < XVECLEN (x, i); j++)
2627 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2633 /* Optimization: a bit-field instruction whose field
2634 happens to be a byte or halfword in memory
2635 can be changed to a move instruction.
2637 We call here when INSN is an insn to examine or store into a bit-field.
2638 BODY is the SET-rtx to be altered.
2640 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2641 (Currently this is called only from function.c, and EQUIV_MEM
2645 optimize_bit_field (body, insn, equiv_mem)
2650 register rtx bitfield;
2653 enum machine_mode mode;
2655 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2656 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2657 bitfield = SET_DEST (body), destflag = 1;
2659 bitfield = SET_SRC (body), destflag = 0;
2661 /* First check that the field being stored has constant size and position
2662 and is in fact a byte or halfword suitably aligned. */
2664 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2665 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2666 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2668 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2670 register rtx memref = 0;
2672 /* Now check that the containing word is memory, not a register,
2673 and that it is safe to change the machine mode. */
2675 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2676 memref = XEXP (bitfield, 0);
2677 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2679 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2680 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2681 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2682 memref = SUBREG_REG (XEXP (bitfield, 0));
2683 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2685 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2686 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2689 && ! mode_dependent_address_p (XEXP (memref, 0))
2690 && ! MEM_VOLATILE_P (memref))
2692 /* Now adjust the address, first for any subreg'ing
2693 that we are now getting rid of,
2694 and then for which byte of the word is wanted. */
2696 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2699 /* Adjust OFFSET to count bits from low-address byte. */
2700 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2701 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2702 - offset - INTVAL (XEXP (bitfield, 1)));
2704 /* Adjust OFFSET to count bytes from low-address byte. */
2705 offset /= BITS_PER_UNIT;
2706 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2708 offset += (SUBREG_BYTE (XEXP (bitfield, 0))
2709 / UNITS_PER_WORD) * UNITS_PER_WORD;
2710 if (BYTES_BIG_ENDIAN)
2711 offset -= (MIN (UNITS_PER_WORD,
2712 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2713 - MIN (UNITS_PER_WORD,
2714 GET_MODE_SIZE (GET_MODE (memref))));
2718 memref = adjust_address (memref, mode, offset);
2719 insns = get_insns ();
2721 emit_insns_before (insns, insn);
2723 /* Store this memory reference where
2724 we found the bit field reference. */
2728 validate_change (insn, &SET_DEST (body), memref, 1);
2729 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2731 rtx src = SET_SRC (body);
2732 while (GET_CODE (src) == SUBREG
2733 && SUBREG_BYTE (src) == 0)
2734 src = SUBREG_REG (src);
2735 if (GET_MODE (src) != GET_MODE (memref))
2736 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2737 validate_change (insn, &SET_SRC (body), src, 1);
2739 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2740 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2741 /* This shouldn't happen because anything that didn't have
2742 one of these modes should have got converted explicitly
2743 and then referenced through a subreg.
2744 This is so because the original bit-field was
2745 handled by agg_mode and so its tree structure had
2746 the same mode that memref now has. */
2751 rtx dest = SET_DEST (body);
2753 while (GET_CODE (dest) == SUBREG
2754 && SUBREG_BYTE (dest) == 0
2755 && (GET_MODE_CLASS (GET_MODE (dest))
2756 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2757 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2759 dest = SUBREG_REG (dest);
2761 validate_change (insn, &SET_DEST (body), dest, 1);
2763 if (GET_MODE (dest) == GET_MODE (memref))
2764 validate_change (insn, &SET_SRC (body), memref, 1);
2767 /* Convert the mem ref to the destination mode. */
2768 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2771 convert_move (newreg, memref,
2772 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2776 validate_change (insn, &SET_SRC (body), newreg, 1);
2780 /* See if we can convert this extraction or insertion into
2781 a simple move insn. We might not be able to do so if this
2782 was, for example, part of a PARALLEL.
2784 If we succeed, write out any needed conversions. If we fail,
2785 it is hard to guess why we failed, so don't do anything
2786 special; just let the optimization be suppressed. */
2788 if (apply_change_group () && seq)
2789 emit_insns_before (seq, insn);
2794 /* These routines are responsible for converting virtual register references
2795 to the actual hard register references once RTL generation is complete.
2797 The following four variables are used for communication between the
2798 routines. They contain the offsets of the virtual registers from their
2799 respective hard registers. */
2801 static int in_arg_offset;
2802 static int var_offset;
2803 static int dynamic_offset;
2804 static int out_arg_offset;
2805 static int cfa_offset;
2807 /* In most machines, the stack pointer register is equivalent to the bottom
2810 #ifndef STACK_POINTER_OFFSET
2811 #define STACK_POINTER_OFFSET 0
2814 /* If not defined, pick an appropriate default for the offset of dynamically
2815 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2816 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2818 #ifndef STACK_DYNAMIC_OFFSET
2820 /* The bottom of the stack points to the actual arguments. If
2821 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2822 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2823 stack space for register parameters is not pushed by the caller, but
2824 rather part of the fixed stack areas and hence not included in
2825 `current_function_outgoing_args_size'. Nevertheless, we must allow
2826 for it when allocating stack dynamic objects. */
2828 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2829 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2830 ((ACCUMULATE_OUTGOING_ARGS \
2831 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2832 + (STACK_POINTER_OFFSET)) \
2835 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2836 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2837 + (STACK_POINTER_OFFSET))
2841 /* On most machines, the CFA coincides with the first incoming parm. */
2843 #ifndef ARG_POINTER_CFA_OFFSET
2844 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2847 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just had
2848 its address taken. DECL is the decl for the object stored in the
2849 register, for later use if we do need to force REG into the stack.
2850 REG is overwritten by the MEM like in put_reg_into_stack. */
2853 gen_mem_addressof (reg, decl)
2857 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2860 /* If the original REG was a user-variable, then so is the REG whose
2861 address is being taken. Likewise for unchanging. */
2862 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2863 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2865 PUT_CODE (reg, MEM);
2869 tree type = TREE_TYPE (decl);
2870 enum machine_mode decl_mode
2871 = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
2872 : DECL_MODE (decl));
2874 PUT_MODE (reg, decl_mode);
2875 MEM_VOLATILE_P (reg) = TREE_SIDE_EFFECTS (decl);
2876 MEM_SET_IN_STRUCT_P (reg, AGGREGATE_TYPE_P (type));
2877 set_mem_alias_set (reg, get_alias_set (decl));
2879 if (TREE_USED (decl) || DECL_INITIAL (decl) != 0)
2880 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), 0);
2884 /* We have no alias information about this newly created MEM. */
2885 set_mem_alias_set (reg, 0);
2887 fixup_var_refs (reg, GET_MODE (reg), 0, 0);
2893 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2896 flush_addressof (decl)
2899 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2900 && DECL_RTL (decl) != 0
2901 && GET_CODE (DECL_RTL (decl)) == MEM
2902 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2903 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2904 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2907 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2910 put_addressof_into_stack (r, ht)
2912 struct hash_table *ht;
2915 int volatile_p, used_p;
2917 rtx reg = XEXP (r, 0);
2919 if (GET_CODE (reg) != REG)
2922 decl = ADDRESSOF_DECL (r);
2925 type = TREE_TYPE (decl);
2926 volatile_p = (TREE_CODE (decl) != SAVE_EXPR
2927 && TREE_THIS_VOLATILE (decl));
2928 used_p = (TREE_USED (decl)
2929 || (TREE_CODE (decl) != SAVE_EXPR
2930 && DECL_INITIAL (decl) != 0));
2939 put_reg_into_stack (0, reg, type, GET_MODE (reg), GET_MODE (reg),
2940 volatile_p, ADDRESSOF_REGNO (r), used_p, ht);
2943 /* List of replacements made below in purge_addressof_1 when creating
2944 bitfield insertions. */
2945 static rtx purge_bitfield_addressof_replacements;
2947 /* List of replacements made below in purge_addressof_1 for patterns
2948 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2949 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2950 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2951 enough in complex cases, e.g. when some field values can be
2952 extracted by usage MEM with narrower mode. */
2953 static rtx purge_addressof_replacements;
2955 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2956 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2957 the stack. If the function returns FALSE then the replacement could not
2961 purge_addressof_1 (loc, insn, force, store, ht)
2965 struct hash_table *ht;
2973 /* Re-start here to avoid recursion in common cases. */
2980 code = GET_CODE (x);
2982 /* If we don't return in any of the cases below, we will recurse inside
2983 the RTX, which will normally result in any ADDRESSOF being forced into
2987 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1, ht);
2988 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0, ht);
2991 else if (code == ADDRESSOF)
2995 if (GET_CODE (XEXP (x, 0)) != MEM)
2997 put_addressof_into_stack (x, ht);
3001 /* We must create a copy of the rtx because it was created by
3002 overwriting a REG rtx which is always shared. */
3003 sub = copy_rtx (XEXP (XEXP (x, 0), 0));
3004 if (validate_change (insn, loc, sub, 0)
3005 || validate_replace_rtx (x, sub, insn))
3009 sub = force_operand (sub, NULL_RTX);
3010 if (! validate_change (insn, loc, sub, 0)
3011 && ! validate_replace_rtx (x, sub, insn))
3014 insns = gen_sequence ();
3016 emit_insn_before (insns, insn);
3020 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
3022 rtx sub = XEXP (XEXP (x, 0), 0);
3024 if (GET_CODE (sub) == MEM)
3025 sub = adjust_address_nv (sub, GET_MODE (x), 0);
3026 else if (GET_CODE (sub) == REG
3027 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
3029 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
3031 int size_x, size_sub;
3035 /* When processing REG_NOTES look at the list of
3036 replacements done on the insn to find the register that X
3040 for (tem = purge_bitfield_addressof_replacements;
3042 tem = XEXP (XEXP (tem, 1), 1))
3043 if (rtx_equal_p (x, XEXP (tem, 0)))
3045 *loc = XEXP (XEXP (tem, 1), 0);
3049 /* See comment for purge_addressof_replacements. */
3050 for (tem = purge_addressof_replacements;
3052 tem = XEXP (XEXP (tem, 1), 1))
3053 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3055 rtx z = XEXP (XEXP (tem, 1), 0);
3057 if (GET_MODE (x) == GET_MODE (z)
3058 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
3059 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
3062 /* It can happen that the note may speak of things
3063 in a wider (or just different) mode than the
3064 code did. This is especially true of
3067 if (GET_CODE (z) == SUBREG && SUBREG_BYTE (z) == 0)
3070 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3071 && (GET_MODE_SIZE (GET_MODE (x))
3072 > GET_MODE_SIZE (GET_MODE (z))))
3074 /* This can occur as a result in invalid
3075 pointer casts, e.g. float f; ...
3076 *(long long int *)&f.
3077 ??? We could emit a warning here, but
3078 without a line number that wouldn't be
3080 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
3083 z = gen_lowpart (GET_MODE (x), z);
3089 /* Sometimes we may not be able to find the replacement. For
3090 example when the original insn was a MEM in a wider mode,
3091 and the note is part of a sign extension of a narrowed
3092 version of that MEM. Gcc testcase compile/990829-1.c can
3093 generate an example of this siutation. Rather than complain
3094 we return false, which will prompt our caller to remove the
3099 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3100 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3102 /* Don't even consider working with paradoxical subregs,
3103 or the moral equivalent seen here. */
3104 if (size_x <= size_sub
3105 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3107 /* Do a bitfield insertion to mirror what would happen
3114 rtx p = PREV_INSN (insn);
3117 val = gen_reg_rtx (GET_MODE (x));
3118 if (! validate_change (insn, loc, val, 0))
3120 /* Discard the current sequence and put the
3121 ADDRESSOF on stack. */
3125 seq = gen_sequence ();
3127 emit_insn_before (seq, insn);
3128 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3132 store_bit_field (sub, size_x, 0, GET_MODE (x),
3133 val, GET_MODE_SIZE (GET_MODE (sub)),
3134 GET_MODE_ALIGNMENT (GET_MODE (sub)));
3136 /* Make sure to unshare any shared rtl that store_bit_field
3137 might have created. */
3138 unshare_all_rtl_again (get_insns ());
3140 seq = gen_sequence ();
3142 p = emit_insn_after (seq, insn);
3143 if (NEXT_INSN (insn))
3144 compute_insns_for_mem (NEXT_INSN (insn),
3145 p ? NEXT_INSN (p) : NULL_RTX,
3150 rtx p = PREV_INSN (insn);
3153 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3154 GET_MODE (x), GET_MODE (x),
3155 GET_MODE_SIZE (GET_MODE (sub)),
3156 GET_MODE_SIZE (GET_MODE (sub)));
3158 if (! validate_change (insn, loc, val, 0))
3160 /* Discard the current sequence and put the
3161 ADDRESSOF on stack. */
3166 seq = gen_sequence ();
3168 emit_insn_before (seq, insn);
3169 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3173 /* Remember the replacement so that the same one can be done
3174 on the REG_NOTES. */
3175 purge_bitfield_addressof_replacements
3176 = gen_rtx_EXPR_LIST (VOIDmode, x,
3179 purge_bitfield_addressof_replacements));
3181 /* We replaced with a reg -- all done. */
3186 else if (validate_change (insn, loc, sub, 0))
3188 /* Remember the replacement so that the same one can be done
3189 on the REG_NOTES. */
3190 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3194 for (tem = purge_addressof_replacements;
3196 tem = XEXP (XEXP (tem, 1), 1))
3197 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3199 XEXP (XEXP (tem, 1), 0) = sub;
3202 purge_addressof_replacements
3203 = gen_rtx (EXPR_LIST, VOIDmode, XEXP (x, 0),
3204 gen_rtx_EXPR_LIST (VOIDmode, sub,
3205 purge_addressof_replacements));
3213 /* Scan all subexpressions. */
3214 fmt = GET_RTX_FORMAT (code);
3215 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3218 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0, ht);
3219 else if (*fmt == 'E')
3220 for (j = 0; j < XVECLEN (x, i); j++)
3221 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0, ht);
3227 /* Return a new hash table entry in HT. */
3229 static struct hash_entry *
3230 insns_for_mem_newfunc (he, ht, k)
3231 struct hash_entry *he;
3232 struct hash_table *ht;
3233 hash_table_key k ATTRIBUTE_UNUSED;
3235 struct insns_for_mem_entry *ifmhe;
3239 ifmhe = ((struct insns_for_mem_entry *)
3240 hash_allocate (ht, sizeof (struct insns_for_mem_entry)));
3241 ifmhe->insns = NULL_RTX;
3246 /* Return a hash value for K, a REG. */
3248 static unsigned long
3249 insns_for_mem_hash (k)
3252 /* K is really a RTX. Just use the address as the hash value. */
3253 return (unsigned long) k;
3256 /* Return non-zero if K1 and K2 (two REGs) are the same. */
3259 insns_for_mem_comp (k1, k2)
3266 struct insns_for_mem_walk_info {
3267 /* The hash table that we are using to record which INSNs use which
3269 struct hash_table *ht;
3271 /* The INSN we are currently proessing. */
3274 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3275 to find the insns that use the REGs in the ADDRESSOFs. */
3279 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3280 that might be used in an ADDRESSOF expression, record this INSN in
3281 the hash table given by DATA (which is really a pointer to an
3282 insns_for_mem_walk_info structure). */
3285 insns_for_mem_walk (r, data)
3289 struct insns_for_mem_walk_info *ifmwi
3290 = (struct insns_for_mem_walk_info *) data;
3292 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3293 && GET_CODE (XEXP (*r, 0)) == REG)
3294 hash_lookup (ifmwi->ht, XEXP (*r, 0), /*create=*/1, /*copy=*/0);
3295 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3297 /* Lookup this MEM in the hashtable, creating it if necessary. */
3298 struct insns_for_mem_entry *ifme
3299 = (struct insns_for_mem_entry *) hash_lookup (ifmwi->ht,
3304 /* If we have not already recorded this INSN, do so now. Since
3305 we process the INSNs in order, we know that if we have
3306 recorded it it must be at the front of the list. */
3307 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3308 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3315 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3316 which REGs in HT. */
3319 compute_insns_for_mem (insns, last_insn, ht)
3322 struct hash_table *ht;
3325 struct insns_for_mem_walk_info ifmwi;
3328 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3329 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3333 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3337 /* Helper function for purge_addressof called through for_each_rtx.
3338 Returns true iff the rtl is an ADDRESSOF. */
3341 is_addressof (rtl, data)
3343 void *data ATTRIBUTE_UNUSED;
3345 return GET_CODE (*rtl) == ADDRESSOF;
3348 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3349 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3353 purge_addressof (insns)
3357 struct hash_table ht;
3359 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3360 requires a fixup pass over the instruction stream to correct
3361 INSNs that depended on the REG being a REG, and not a MEM. But,
3362 these fixup passes are slow. Furthermore, most MEMs are not
3363 mentioned in very many instructions. So, we speed up the process
3364 by pre-calculating which REGs occur in which INSNs; that allows
3365 us to perform the fixup passes much more quickly. */
3366 hash_table_init (&ht,
3367 insns_for_mem_newfunc,
3369 insns_for_mem_comp);
3370 compute_insns_for_mem (insns, NULL_RTX, &ht);
3372 for (insn = insns; insn; insn = NEXT_INSN (insn))
3373 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3374 || GET_CODE (insn) == CALL_INSN)
3376 if (! purge_addressof_1 (&PATTERN (insn), insn,
3377 asm_noperands (PATTERN (insn)) > 0, 0, &ht))
3378 /* If we could not replace the ADDRESSOFs in the insn,
3379 something is wrong. */
3382 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, &ht))
3384 /* If we could not replace the ADDRESSOFs in the insn's notes,
3385 we can just remove the offending notes instead. */
3388 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3390 /* If we find a REG_RETVAL note then the insn is a libcall.
3391 Such insns must have REG_EQUAL notes as well, in order
3392 for later passes of the compiler to work. So it is not
3393 safe to delete the notes here, and instead we abort. */
3394 if (REG_NOTE_KIND (note) == REG_RETVAL)
3396 if (for_each_rtx (¬e, is_addressof, NULL))
3397 remove_note (insn, note);
3403 hash_table_free (&ht);
3404 purge_bitfield_addressof_replacements = 0;
3405 purge_addressof_replacements = 0;
3407 /* REGs are shared. purge_addressof will destructively replace a REG
3408 with a MEM, which creates shared MEMs.
3410 Unfortunately, the children of put_reg_into_stack assume that MEMs
3411 referring to the same stack slot are shared (fixup_var_refs and
3412 the associated hash table code).
3414 So, we have to do another unsharing pass after we have flushed any
3415 REGs that had their address taken into the stack.
3417 It may be worth tracking whether or not we converted any REGs into
3418 MEMs to avoid this overhead when it is not needed. */
3419 unshare_all_rtl_again (get_insns ());
3422 /* Convert a SET of a hard subreg to a set of the appropriet hard
3423 register. A subroutine of purge_hard_subreg_sets. */
3426 purge_single_hard_subreg_set (pattern)
3429 rtx reg = SET_DEST (pattern);
3430 enum machine_mode mode = GET_MODE (SET_DEST (pattern));
3433 if (GET_CODE (reg) == SUBREG && GET_CODE (SUBREG_REG (reg)) == REG
3434 && REGNO (SUBREG_REG (reg)) < FIRST_PSEUDO_REGISTER)
3436 offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)),
3437 GET_MODE (SUBREG_REG (reg)),
3440 reg = SUBREG_REG (reg);
3444 if (GET_CODE (reg) == REG && REGNO (reg) < FIRST_PSEUDO_REGISTER)
3446 reg = gen_rtx_REG (mode, REGNO (reg) + offset);
3447 SET_DEST (pattern) = reg;
3451 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The
3452 only such SETs that we expect to see are those left in because
3453 integrate can't handle sets of parts of a return value register.
3455 We don't use alter_subreg because we only want to eliminate subregs
3456 of hard registers. */
3459 purge_hard_subreg_sets (insn)
3462 for (; insn; insn = NEXT_INSN (insn))
3466 rtx pattern = PATTERN (insn);
3467 switch (GET_CODE (pattern))
3470 if (GET_CODE (SET_DEST (pattern)) == SUBREG)
3471 purge_single_hard_subreg_set (pattern);
3476 for (j = XVECLEN (pattern, 0) - 1; j >= 0; j--)
3478 rtx inner_pattern = XVECEXP (pattern, 0, j);
3479 if (GET_CODE (inner_pattern) == SET
3480 && GET_CODE (SET_DEST (inner_pattern)) == SUBREG)
3481 purge_single_hard_subreg_set (inner_pattern);
3492 /* Pass through the INSNS of function FNDECL and convert virtual register
3493 references to hard register references. */
3496 instantiate_virtual_regs (fndecl, insns)
3503 /* Compute the offsets to use for this function. */
3504 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3505 var_offset = STARTING_FRAME_OFFSET;
3506 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3507 out_arg_offset = STACK_POINTER_OFFSET;
3508 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl);
3510 /* Scan all variables and parameters of this function. For each that is
3511 in memory, instantiate all virtual registers if the result is a valid
3512 address. If not, we do it later. That will handle most uses of virtual
3513 regs on many machines. */
3514 instantiate_decls (fndecl, 1);
3516 /* Initialize recognition, indicating that volatile is OK. */
3519 /* Scan through all the insns, instantiating every virtual register still
3521 for (insn = insns; insn; insn = NEXT_INSN (insn))
3522 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3523 || GET_CODE (insn) == CALL_INSN)
3525 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3526 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3527 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
3528 if (GET_CODE (insn) == CALL_INSN)
3529 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn),
3533 /* Instantiate the stack slots for the parm registers, for later use in
3534 addressof elimination. */
3535 for (i = 0; i < max_parm_reg; ++i)
3536 if (parm_reg_stack_loc[i])
3537 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3539 /* Now instantiate the remaining register equivalences for debugging info.
3540 These will not be valid addresses. */
3541 instantiate_decls (fndecl, 0);
3543 /* Indicate that, from now on, assign_stack_local should use
3544 frame_pointer_rtx. */
3545 virtuals_instantiated = 1;
3548 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3549 all virtual registers in their DECL_RTL's.
3551 If VALID_ONLY, do this only if the resulting address is still valid.
3552 Otherwise, always do it. */
3555 instantiate_decls (fndecl, valid_only)
3561 /* Process all parameters of the function. */
3562 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3564 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3565 HOST_WIDE_INT size_rtl;
3567 instantiate_decl (DECL_RTL (decl), size, valid_only);
3569 /* If the parameter was promoted, then the incoming RTL mode may be
3570 larger than the declared type size. We must use the larger of
3572 size_rtl = GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl)));
3573 size = MAX (size_rtl, size);
3574 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3577 /* Now process all variables defined in the function or its subblocks. */
3578 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3581 /* Subroutine of instantiate_decls: Process all decls in the given
3582 BLOCK node and all its subblocks. */
3585 instantiate_decls_1 (let, valid_only)
3591 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3592 if (DECL_RTL_SET_P (t))
3593 instantiate_decl (DECL_RTL (t),
3594 int_size_in_bytes (TREE_TYPE (t)),
3597 /* Process all subblocks. */
3598 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3599 instantiate_decls_1 (t, valid_only);
3602 /* Subroutine of the preceding procedures: Given RTL representing a
3603 decl and the size of the object, do any instantiation required.
3605 If VALID_ONLY is non-zero, it means that the RTL should only be
3606 changed if the new address is valid. */
3609 instantiate_decl (x, size, valid_only)
3614 enum machine_mode mode;
3617 /* If this is not a MEM, no need to do anything. Similarly if the
3618 address is a constant or a register that is not a virtual register. */
3620 if (x == 0 || GET_CODE (x) != MEM)
3624 if (CONSTANT_P (addr)
3625 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3626 || (GET_CODE (addr) == REG
3627 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3628 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3631 /* If we should only do this if the address is valid, copy the address.
3632 We need to do this so we can undo any changes that might make the
3633 address invalid. This copy is unfortunate, but probably can't be
3637 addr = copy_rtx (addr);
3639 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3641 if (valid_only && size >= 0)
3643 unsigned HOST_WIDE_INT decl_size = size;
3645 /* Now verify that the resulting address is valid for every integer or
3646 floating-point mode up to and including SIZE bytes long. We do this
3647 since the object might be accessed in any mode and frame addresses
3650 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3651 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3652 mode = GET_MODE_WIDER_MODE (mode))
3653 if (! memory_address_p (mode, addr))
3656 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3657 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3658 mode = GET_MODE_WIDER_MODE (mode))
3659 if (! memory_address_p (mode, addr))
3663 /* Put back the address now that we have updated it and we either know
3664 it is valid or we don't care whether it is valid. */
3669 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
3670 is a virtual register, return the requivalent hard register and set the
3671 offset indirectly through the pointer. Otherwise, return 0. */
3674 instantiate_new_reg (x, poffset)
3676 HOST_WIDE_INT *poffset;
3679 HOST_WIDE_INT offset;
3681 if (x == virtual_incoming_args_rtx)
3682 new = arg_pointer_rtx, offset = in_arg_offset;
3683 else if (x == virtual_stack_vars_rtx)
3684 new = frame_pointer_rtx, offset = var_offset;
3685 else if (x == virtual_stack_dynamic_rtx)
3686 new = stack_pointer_rtx, offset = dynamic_offset;
3687 else if (x == virtual_outgoing_args_rtx)
3688 new = stack_pointer_rtx, offset = out_arg_offset;
3689 else if (x == virtual_cfa_rtx)
3690 new = arg_pointer_rtx, offset = cfa_offset;
3698 /* Given a pointer to a piece of rtx and an optional pointer to the
3699 containing object, instantiate any virtual registers present in it.
3701 If EXTRA_INSNS, we always do the replacement and generate
3702 any extra insns before OBJECT. If it zero, we do nothing if replacement
3705 Return 1 if we either had nothing to do or if we were able to do the
3706 needed replacement. Return 0 otherwise; we only return zero if
3707 EXTRA_INSNS is zero.
3709 We first try some simple transformations to avoid the creation of extra
3713 instantiate_virtual_regs_1 (loc, object, extra_insns)
3721 HOST_WIDE_INT offset = 0;
3727 /* Re-start here to avoid recursion in common cases. */
3734 code = GET_CODE (x);
3736 /* Check for some special cases. */
3753 /* We are allowed to set the virtual registers. This means that
3754 the actual register should receive the source minus the
3755 appropriate offset. This is used, for example, in the handling
3756 of non-local gotos. */
3757 if ((new = instantiate_new_reg (SET_DEST (x), &offset)) != 0)
3759 rtx src = SET_SRC (x);
3761 /* We are setting the register, not using it, so the relevant
3762 offset is the negative of the offset to use were we using
3765 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3767 /* The only valid sources here are PLUS or REG. Just do
3768 the simplest possible thing to handle them. */
3769 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3773 if (GET_CODE (src) != REG)
3774 temp = force_operand (src, NULL_RTX);
3777 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3781 emit_insns_before (seq, object);
3784 if (! validate_change (object, &SET_SRC (x), temp, 0)
3791 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3796 /* Handle special case of virtual register plus constant. */
3797 if (CONSTANT_P (XEXP (x, 1)))
3799 rtx old, new_offset;
3801 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3802 if (GET_CODE (XEXP (x, 0)) == PLUS)
3804 if ((new = instantiate_new_reg (XEXP (XEXP (x, 0), 0), &offset)))
3806 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3808 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3817 #ifdef POINTERS_EXTEND_UNSIGNED
3818 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
3819 we can commute the PLUS and SUBREG because pointers into the
3820 frame are well-behaved. */
3821 else if (GET_CODE (XEXP (x, 0)) == SUBREG && GET_MODE (x) == ptr_mode
3822 && GET_CODE (XEXP (x, 1)) == CONST_INT
3824 = instantiate_new_reg (SUBREG_REG (XEXP (x, 0)),
3826 && validate_change (object, loc,
3827 plus_constant (gen_lowpart (ptr_mode,
3830 + INTVAL (XEXP (x, 1))),
3834 else if ((new = instantiate_new_reg (XEXP (x, 0), &offset)) == 0)
3836 /* We know the second operand is a constant. Unless the
3837 first operand is a REG (which has been already checked),
3838 it needs to be checked. */
3839 if (GET_CODE (XEXP (x, 0)) != REG)
3847 new_offset = plus_constant (XEXP (x, 1), offset);
3849 /* If the new constant is zero, try to replace the sum with just
3851 if (new_offset == const0_rtx
3852 && validate_change (object, loc, new, 0))
3855 /* Next try to replace the register and new offset.
3856 There are two changes to validate here and we can't assume that
3857 in the case of old offset equals new just changing the register
3858 will yield a valid insn. In the interests of a little efficiency,
3859 however, we only call validate change once (we don't queue up the
3860 changes and then call apply_change_group). */
3864 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3865 : (XEXP (x, 0) = new,
3866 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3874 /* Otherwise copy the new constant into a register and replace
3875 constant with that register. */
3876 temp = gen_reg_rtx (Pmode);
3878 if (validate_change (object, &XEXP (x, 1), temp, 0))
3879 emit_insn_before (gen_move_insn (temp, new_offset), object);
3882 /* If that didn't work, replace this expression with a
3883 register containing the sum. */
3886 new = gen_rtx_PLUS (Pmode, new, new_offset);
3889 temp = force_operand (new, NULL_RTX);
3893 emit_insns_before (seq, object);
3894 if (! validate_change (object, loc, temp, 0)
3895 && ! validate_replace_rtx (x, temp, object))
3903 /* Fall through to generic two-operand expression case. */
3909 case DIV: case UDIV:
3910 case MOD: case UMOD:
3911 case AND: case IOR: case XOR:
3912 case ROTATERT: case ROTATE:
3913 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3915 case GE: case GT: case GEU: case GTU:
3916 case LE: case LT: case LEU: case LTU:
3917 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3918 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3923 /* Most cases of MEM that convert to valid addresses have already been
3924 handled by our scan of decls. The only special handling we
3925 need here is to make a copy of the rtx to ensure it isn't being
3926 shared if we have to change it to a pseudo.
3928 If the rtx is a simple reference to an address via a virtual register,
3929 it can potentially be shared. In such cases, first try to make it
3930 a valid address, which can also be shared. Otherwise, copy it and
3933 First check for common cases that need no processing. These are
3934 usually due to instantiation already being done on a previous instance
3938 if (CONSTANT_ADDRESS_P (temp)
3939 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3940 || temp == arg_pointer_rtx
3942 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3943 || temp == hard_frame_pointer_rtx
3945 || temp == frame_pointer_rtx)
3948 if (GET_CODE (temp) == PLUS
3949 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3950 && (XEXP (temp, 0) == frame_pointer_rtx
3951 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3952 || XEXP (temp, 0) == hard_frame_pointer_rtx
3954 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3955 || XEXP (temp, 0) == arg_pointer_rtx
3960 if (temp == virtual_stack_vars_rtx
3961 || temp == virtual_incoming_args_rtx
3962 || (GET_CODE (temp) == PLUS
3963 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3964 && (XEXP (temp, 0) == virtual_stack_vars_rtx
3965 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
3967 /* This MEM may be shared. If the substitution can be done without
3968 the need to generate new pseudos, we want to do it in place
3969 so all copies of the shared rtx benefit. The call below will
3970 only make substitutions if the resulting address is still
3973 Note that we cannot pass X as the object in the recursive call
3974 since the insn being processed may not allow all valid
3975 addresses. However, if we were not passed on object, we can
3976 only modify X without copying it if X will have a valid
3979 ??? Also note that this can still lose if OBJECT is an insn that
3980 has less restrictions on an address that some other insn.
3981 In that case, we will modify the shared address. This case
3982 doesn't seem very likely, though. One case where this could
3983 happen is in the case of a USE or CLOBBER reference, but we
3984 take care of that below. */
3986 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
3987 object ? object : x, 0))
3990 /* Otherwise make a copy and process that copy. We copy the entire
3991 RTL expression since it might be a PLUS which could also be
3993 *loc = x = copy_rtx (x);
3996 /* Fall through to generic unary operation case. */
3998 case STRICT_LOW_PART:
4000 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
4001 case SIGN_EXTEND: case ZERO_EXTEND:
4002 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
4003 case FLOAT: case FIX:
4004 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
4008 /* These case either have just one operand or we know that we need not
4009 check the rest of the operands. */
4015 /* If the operand is a MEM, see if the change is a valid MEM. If not,
4016 go ahead and make the invalid one, but do it to a copy. For a REG,
4017 just make the recursive call, since there's no chance of a problem. */
4019 if ((GET_CODE (XEXP (x, 0)) == MEM
4020 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
4022 || (GET_CODE (XEXP (x, 0)) == REG
4023 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
4026 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
4031 /* Try to replace with a PLUS. If that doesn't work, compute the sum
4032 in front of this insn and substitute the temporary. */
4033 if ((new = instantiate_new_reg (x, &offset)) != 0)
4035 temp = plus_constant (new, offset);
4036 if (!validate_change (object, loc, temp, 0))
4042 temp = force_operand (temp, NULL_RTX);
4046 emit_insns_before (seq, object);
4047 if (! validate_change (object, loc, temp, 0)
4048 && ! validate_replace_rtx (x, temp, object))
4056 if (GET_CODE (XEXP (x, 0)) == REG)
4059 else if (GET_CODE (XEXP (x, 0)) == MEM)
4061 /* If we have a (addressof (mem ..)), do any instantiation inside
4062 since we know we'll be making the inside valid when we finally
4063 remove the ADDRESSOF. */
4064 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
4073 /* Scan all subexpressions. */
4074 fmt = GET_RTX_FORMAT (code);
4075 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
4078 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
4081 else if (*fmt == 'E')
4082 for (j = 0; j < XVECLEN (x, i); j++)
4083 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
4090 /* Optimization: assuming this function does not receive nonlocal gotos,
4091 delete the handlers for such, as well as the insns to establish
4092 and disestablish them. */
4098 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4100 /* Delete the handler by turning off the flag that would
4101 prevent jump_optimize from deleting it.
4102 Also permit deletion of the nonlocal labels themselves
4103 if nothing local refers to them. */
4104 if (GET_CODE (insn) == CODE_LABEL)
4108 LABEL_PRESERVE_P (insn) = 0;
4110 /* Remove it from the nonlocal_label list, to avoid confusing
4112 for (t = nonlocal_labels, last_t = 0; t;
4113 last_t = t, t = TREE_CHAIN (t))
4114 if (DECL_RTL (TREE_VALUE (t)) == insn)
4119 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
4121 TREE_CHAIN (last_t) = TREE_CHAIN (t);
4124 if (GET_CODE (insn) == INSN)
4128 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
4129 if (reg_mentioned_p (t, PATTERN (insn)))
4135 || (nonlocal_goto_stack_level != 0
4136 && reg_mentioned_p (nonlocal_goto_stack_level,
4146 return max_parm_reg;
4149 /* Return the first insn following those generated by `assign_parms'. */
4152 get_first_nonparm_insn ()
4155 return NEXT_INSN (last_parm_insn);
4156 return get_insns ();
4159 /* Return the first NOTE_INSN_BLOCK_BEG note in the function.
4160 Crash if there is none. */
4163 get_first_block_beg ()
4165 register rtx searcher;
4166 register rtx insn = get_first_nonparm_insn ();
4168 for (searcher = insn; searcher; searcher = NEXT_INSN (searcher))
4169 if (GET_CODE (searcher) == NOTE
4170 && NOTE_LINE_NUMBER (searcher) == NOTE_INSN_BLOCK_BEG)
4173 abort (); /* Invalid call to this function. (See comments above.) */
4177 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4178 This means a type for which function calls must pass an address to the
4179 function or get an address back from the function.
4180 EXP may be a type node or an expression (whose type is tested). */
4183 aggregate_value_p (exp)
4186 int i, regno, nregs;
4189 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4191 if (TREE_CODE (type) == VOID_TYPE)
4193 if (RETURN_IN_MEMORY (type))
4195 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4196 and thus can't be returned in registers. */
4197 if (TREE_ADDRESSABLE (type))
4199 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4201 /* Make sure we have suitable call-clobbered regs to return
4202 the value in; if not, we must return it in memory. */
4203 reg = hard_function_value (type, 0, 0);
4205 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4207 if (GET_CODE (reg) != REG)
4210 regno = REGNO (reg);
4211 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
4212 for (i = 0; i < nregs; i++)
4213 if (! call_used_regs[regno + i])
4218 /* Assign RTL expressions to the function's parameters.
4219 This may involve copying them into registers and using
4220 those registers as the RTL for them. */
4223 assign_parms (fndecl)
4227 register rtx entry_parm = 0;
4228 register rtx stack_parm = 0;
4229 CUMULATIVE_ARGS args_so_far;
4230 enum machine_mode promoted_mode, passed_mode;
4231 enum machine_mode nominal_mode, promoted_nominal_mode;
4233 /* Total space needed so far for args on the stack,
4234 given as a constant and a tree-expression. */
4235 struct args_size stack_args_size;
4236 tree fntype = TREE_TYPE (fndecl);
4237 tree fnargs = DECL_ARGUMENTS (fndecl);
4238 /* This is used for the arg pointer when referring to stack args. */
4239 rtx internal_arg_pointer;
4240 /* This is a dummy PARM_DECL that we used for the function result if
4241 the function returns a structure. */
4242 tree function_result_decl = 0;
4243 #ifdef SETUP_INCOMING_VARARGS
4244 int varargs_setup = 0;
4246 rtx conversion_insns = 0;
4247 struct args_size alignment_pad;
4249 /* Nonzero if the last arg is named `__builtin_va_alist',
4250 which is used on some machines for old-fashioned non-ANSI varargs.h;
4251 this should be stuck onto the stack as if it had arrived there. */
4253 = (current_function_varargs
4255 && (parm = tree_last (fnargs)) != 0
4257 && (! strcmp (IDENTIFIER_POINTER (DECL_NAME (parm)),
4258 "__builtin_va_alist")));
4260 /* Nonzero if function takes extra anonymous args.
4261 This means the last named arg must be on the stack
4262 right before the anonymous ones. */
4264 = (TYPE_ARG_TYPES (fntype) != 0
4265 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4266 != void_type_node));
4268 current_function_stdarg = stdarg;
4270 /* If the reg that the virtual arg pointer will be translated into is
4271 not a fixed reg or is the stack pointer, make a copy of the virtual
4272 arg pointer, and address parms via the copy. The frame pointer is
4273 considered fixed even though it is not marked as such.
4275 The second time through, simply use ap to avoid generating rtx. */
4277 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4278 || ! (fixed_regs[ARG_POINTER_REGNUM]
4279 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4280 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4282 internal_arg_pointer = virtual_incoming_args_rtx;
4283 current_function_internal_arg_pointer = internal_arg_pointer;
4285 stack_args_size.constant = 0;
4286 stack_args_size.var = 0;
4288 /* If struct value address is treated as the first argument, make it so. */
4289 if (aggregate_value_p (DECL_RESULT (fndecl))
4290 && ! current_function_returns_pcc_struct
4291 && struct_value_incoming_rtx == 0)
4293 tree type = build_pointer_type (TREE_TYPE (fntype));
4295 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4297 DECL_ARG_TYPE (function_result_decl) = type;
4298 TREE_CHAIN (function_result_decl) = fnargs;
4299 fnargs = function_result_decl;
4302 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4303 parm_reg_stack_loc = (rtx *) xcalloc (max_parm_reg, sizeof (rtx));
4305 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4306 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4308 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, 0);
4311 /* We haven't yet found an argument that we must push and pretend the
4313 current_function_pretend_args_size = 0;
4315 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4317 struct args_size stack_offset;
4318 struct args_size arg_size;
4319 int passed_pointer = 0;
4320 int did_conversion = 0;
4321 tree passed_type = DECL_ARG_TYPE (parm);
4322 tree nominal_type = TREE_TYPE (parm);
4325 /* Set LAST_NAMED if this is last named arg before some
4327 int last_named = ((TREE_CHAIN (parm) == 0
4328 || DECL_NAME (TREE_CHAIN (parm)) == 0)
4329 && (stdarg || current_function_varargs));
4330 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4331 most machines, if this is a varargs/stdarg function, then we treat
4332 the last named arg as if it were anonymous too. */
4333 int named_arg = STRICT_ARGUMENT_NAMING ? 1 : ! last_named;
4335 if (TREE_TYPE (parm) == error_mark_node
4336 /* This can happen after weird syntax errors
4337 or if an enum type is defined among the parms. */
4338 || TREE_CODE (parm) != PARM_DECL
4339 || passed_type == NULL)
4341 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx));
4342 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4343 TREE_USED (parm) = 1;
4347 /* For varargs.h function, save info about regs and stack space
4348 used by the individual args, not including the va_alist arg. */
4349 if (hide_last_arg && last_named)
4350 current_function_args_info = args_so_far;
4352 /* Find mode of arg as it is passed, and mode of arg
4353 as it should be during execution of this function. */
4354 passed_mode = TYPE_MODE (passed_type);
4355 nominal_mode = TYPE_MODE (nominal_type);
4357 /* If the parm's mode is VOID, its value doesn't matter,
4358 and avoid the usual things like emit_move_insn that could crash. */
4359 if (nominal_mode == VOIDmode)
4361 SET_DECL_RTL (parm, const0_rtx);
4362 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4366 /* If the parm is to be passed as a transparent union, use the
4367 type of the first field for the tests below. We have already
4368 verified that the modes are the same. */
4369 if (DECL_TRANSPARENT_UNION (parm)
4370 || (TREE_CODE (passed_type) == UNION_TYPE
4371 && TYPE_TRANSPARENT_UNION (passed_type)))
4372 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4374 /* See if this arg was passed by invisible reference. It is if
4375 it is an object whose size depends on the contents of the
4376 object itself or if the machine requires these objects be passed
4379 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
4380 && contains_placeholder_p (TYPE_SIZE (passed_type)))
4381 || TREE_ADDRESSABLE (passed_type)
4382 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4383 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4384 passed_type, named_arg)
4388 passed_type = nominal_type = build_pointer_type (passed_type);
4390 passed_mode = nominal_mode = Pmode;
4393 promoted_mode = passed_mode;
4395 #ifdef PROMOTE_FUNCTION_ARGS
4396 /* Compute the mode in which the arg is actually extended to. */
4397 unsignedp = TREE_UNSIGNED (passed_type);
4398 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4401 /* Let machine desc say which reg (if any) the parm arrives in.
4402 0 means it arrives on the stack. */
4403 #ifdef FUNCTION_INCOMING_ARG
4404 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4405 passed_type, named_arg);
4407 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4408 passed_type, named_arg);
4411 if (entry_parm == 0)
4412 promoted_mode = passed_mode;
4414 #ifdef SETUP_INCOMING_VARARGS
4415 /* If this is the last named parameter, do any required setup for
4416 varargs or stdargs. We need to know about the case of this being an
4417 addressable type, in which case we skip the registers it
4418 would have arrived in.
4420 For stdargs, LAST_NAMED will be set for two parameters, the one that
4421 is actually the last named, and the dummy parameter. We only
4422 want to do this action once.
4424 Also, indicate when RTL generation is to be suppressed. */
4425 if (last_named && !varargs_setup)
4427 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
4428 current_function_pretend_args_size, 0);
4433 /* Determine parm's home in the stack,
4434 in case it arrives in the stack or we should pretend it did.
4436 Compute the stack position and rtx where the argument arrives
4439 There is one complexity here: If this was a parameter that would
4440 have been passed in registers, but wasn't only because it is
4441 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4442 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4443 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4444 0 as it was the previous time. */
4446 pretend_named = named_arg || PRETEND_OUTGOING_VARARGS_NAMED;
4447 locate_and_pad_parm (promoted_mode, passed_type,
4448 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4451 #ifdef FUNCTION_INCOMING_ARG
4452 FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4454 pretend_named) != 0,
4456 FUNCTION_ARG (args_so_far, promoted_mode,
4458 pretend_named) != 0,
4461 fndecl, &stack_args_size, &stack_offset, &arg_size,
4465 rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
4467 if (offset_rtx == const0_rtx)
4468 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4470 stack_parm = gen_rtx_MEM (promoted_mode,
4471 gen_rtx_PLUS (Pmode,
4472 internal_arg_pointer,
4475 set_mem_attributes (stack_parm, parm, 1);
4478 /* If this parameter was passed both in registers and in the stack,
4479 use the copy on the stack. */
4480 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4483 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4484 /* If this parm was passed part in regs and part in memory,
4485 pretend it arrived entirely in memory
4486 by pushing the register-part onto the stack.
4488 In the special case of a DImode or DFmode that is split,
4489 we could put it together in a pseudoreg directly,
4490 but for now that's not worth bothering with. */
4494 int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4495 passed_type, named_arg);
4499 current_function_pretend_args_size
4500 = (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
4501 / (PARM_BOUNDARY / BITS_PER_UNIT)
4502 * (PARM_BOUNDARY / BITS_PER_UNIT));
4504 /* Handle calls that pass values in multiple non-contiguous
4505 locations. The Irix 6 ABI has examples of this. */
4506 if (GET_CODE (entry_parm) == PARALLEL)
4507 emit_group_store (validize_mem (stack_parm), entry_parm,
4508 int_size_in_bytes (TREE_TYPE (parm)),
4509 TYPE_ALIGN (TREE_TYPE (parm)));
4512 move_block_from_reg (REGNO (entry_parm),
4513 validize_mem (stack_parm), nregs,
4514 int_size_in_bytes (TREE_TYPE (parm)));
4516 entry_parm = stack_parm;
4521 /* If we didn't decide this parm came in a register,
4522 by default it came on the stack. */
4523 if (entry_parm == 0)
4524 entry_parm = stack_parm;
4526 /* Record permanently how this parm was passed. */
4527 DECL_INCOMING_RTL (parm) = entry_parm;
4529 /* If there is actually space on the stack for this parm,
4530 count it in stack_args_size; otherwise set stack_parm to 0
4531 to indicate there is no preallocated stack slot for the parm. */
4533 if (entry_parm == stack_parm
4534 || (GET_CODE (entry_parm) == PARALLEL
4535 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4536 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4537 /* On some machines, even if a parm value arrives in a register
4538 there is still an (uninitialized) stack slot allocated for it.
4540 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4541 whether this parameter already has a stack slot allocated,
4542 because an arg block exists only if current_function_args_size
4543 is larger than some threshold, and we haven't calculated that
4544 yet. So, for now, we just assume that stack slots never exist
4546 || REG_PARM_STACK_SPACE (fndecl) > 0
4550 stack_args_size.constant += arg_size.constant;
4552 ADD_PARM_SIZE (stack_args_size, arg_size.var);
4555 /* No stack slot was pushed for this parm. */
4558 /* Update info on where next arg arrives in registers. */
4560 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4561 passed_type, named_arg);
4563 /* If we can't trust the parm stack slot to be aligned enough
4564 for its ultimate type, don't use that slot after entry.
4565 We'll make another stack slot, if we need one. */
4567 unsigned int thisparm_boundary
4568 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4570 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4574 /* If parm was passed in memory, and we need to convert it on entry,
4575 don't store it back in that same slot. */
4577 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4580 /* When an argument is passed in multiple locations, we can't
4581 make use of this information, but we can save some copying if
4582 the whole argument is passed in a single register. */
4583 if (GET_CODE (entry_parm) == PARALLEL
4584 && nominal_mode != BLKmode && passed_mode != BLKmode)
4586 int i, len = XVECLEN (entry_parm, 0);
4588 for (i = 0; i < len; i++)
4589 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
4590 && GET_CODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) == REG
4591 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
4593 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
4595 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
4596 DECL_INCOMING_RTL (parm) = entry_parm;
4601 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4602 in the mode in which it arrives.
4603 STACK_PARM is an RTX for a stack slot where the parameter can live
4604 during the function (in case we want to put it there).
4605 STACK_PARM is 0 if no stack slot was pushed for it.
4607 Now output code if necessary to convert ENTRY_PARM to
4608 the type in which this function declares it,
4609 and store that result in an appropriate place,
4610 which may be a pseudo reg, may be STACK_PARM,
4611 or may be a local stack slot if STACK_PARM is 0.
4613 Set DECL_RTL to that place. */
4615 if (nominal_mode == BLKmode || GET_CODE (entry_parm) == PARALLEL)
4617 /* If a BLKmode arrives in registers, copy it to a stack slot.
4618 Handle calls that pass values in multiple non-contiguous
4619 locations. The Irix 6 ABI has examples of this. */
4620 if (GET_CODE (entry_parm) == REG
4621 || GET_CODE (entry_parm) == PARALLEL)
4624 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
4627 /* Note that we will be storing an integral number of words.
4628 So we have to be careful to ensure that we allocate an
4629 integral number of words. We do this below in the
4630 assign_stack_local if space was not allocated in the argument
4631 list. If it was, this will not work if PARM_BOUNDARY is not
4632 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4633 if it becomes a problem. */
4635 if (stack_parm == 0)
4638 = assign_stack_local (GET_MODE (entry_parm),
4640 set_mem_attributes (stack_parm, parm, 1);
4643 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4646 /* Handle calls that pass values in multiple non-contiguous
4647 locations. The Irix 6 ABI has examples of this. */
4648 if (GET_CODE (entry_parm) == PARALLEL)
4649 emit_group_store (validize_mem (stack_parm), entry_parm,
4650 int_size_in_bytes (TREE_TYPE (parm)),
4651 TYPE_ALIGN (TREE_TYPE (parm)));
4653 move_block_from_reg (REGNO (entry_parm),
4654 validize_mem (stack_parm),
4655 size_stored / UNITS_PER_WORD,
4656 int_size_in_bytes (TREE_TYPE (parm)));
4658 SET_DECL_RTL (parm, stack_parm);
4660 else if (! ((! optimize
4661 && ! DECL_REGISTER (parm)
4662 && ! DECL_INLINE (fndecl))
4663 || TREE_SIDE_EFFECTS (parm)
4664 /* If -ffloat-store specified, don't put explicit
4665 float variables into registers. */
4666 || (flag_float_store
4667 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4668 /* Always assign pseudo to structure return or item passed
4669 by invisible reference. */
4670 || passed_pointer || parm == function_result_decl)
4672 /* Store the parm in a pseudoregister during the function, but we
4673 may need to do it in a wider mode. */
4675 register rtx parmreg;
4676 unsigned int regno, regnoi = 0, regnor = 0;
4678 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4680 promoted_nominal_mode
4681 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4683 parmreg = gen_reg_rtx (promoted_nominal_mode);
4684 mark_user_reg (parmreg);
4686 /* If this was an item that we received a pointer to, set DECL_RTL
4691 gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)),
4693 set_mem_attributes (DECL_RTL (parm), parm, 1);
4697 SET_DECL_RTL (parm, parmreg);
4698 maybe_set_unchanging (DECL_RTL (parm), parm);
4701 /* Copy the value into the register. */
4702 if (nominal_mode != passed_mode
4703 || promoted_nominal_mode != promoted_mode)
4706 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4707 mode, by the caller. We now have to convert it to
4708 NOMINAL_MODE, if different. However, PARMREG may be in
4709 a different mode than NOMINAL_MODE if it is being stored
4712 If ENTRY_PARM is a hard register, it might be in a register
4713 not valid for operating in its mode (e.g., an odd-numbered
4714 register for a DFmode). In that case, moves are the only
4715 thing valid, so we can't do a convert from there. This
4716 occurs when the calling sequence allow such misaligned
4719 In addition, the conversion may involve a call, which could
4720 clobber parameters which haven't been copied to pseudo
4721 registers yet. Therefore, we must first copy the parm to
4722 a pseudo reg here, and save the conversion until after all
4723 parameters have been moved. */
4725 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4727 emit_move_insn (tempreg, validize_mem (entry_parm));
4729 push_to_sequence (conversion_insns);
4730 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4732 if (GET_CODE (tempreg) == SUBREG
4733 && GET_MODE (tempreg) == nominal_mode
4734 && GET_CODE (SUBREG_REG (tempreg)) == REG
4735 && nominal_mode == passed_mode
4736 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm)
4737 && GET_MODE_SIZE (GET_MODE (tempreg))
4738 < GET_MODE_SIZE (GET_MODE (entry_parm)))
4740 /* The argument is already sign/zero extended, so note it
4742 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
4743 SUBREG_PROMOTED_UNSIGNED_P (tempreg) = unsignedp;
4746 /* TREE_USED gets set erroneously during expand_assignment. */
4747 save_tree_used = TREE_USED (parm);
4748 expand_assignment (parm,
4749 make_tree (nominal_type, tempreg), 0, 0);
4750 TREE_USED (parm) = save_tree_used;
4751 conversion_insns = get_insns ();
4756 emit_move_insn (parmreg, validize_mem (entry_parm));
4758 /* If we were passed a pointer but the actual value
4759 can safely live in a register, put it in one. */
4760 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4762 && ! DECL_REGISTER (parm)
4763 && ! DECL_INLINE (fndecl))
4764 || TREE_SIDE_EFFECTS (parm)
4765 /* If -ffloat-store specified, don't put explicit
4766 float variables into registers. */
4767 || (flag_float_store
4768 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE)))
4770 /* We can't use nominal_mode, because it will have been set to
4771 Pmode above. We must use the actual mode of the parm. */
4772 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4773 mark_user_reg (parmreg);
4774 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
4776 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
4777 int unsigned_p = TREE_UNSIGNED (TREE_TYPE (parm));
4778 push_to_sequence (conversion_insns);
4779 emit_move_insn (tempreg, DECL_RTL (parm));
4781 convert_to_mode (GET_MODE (parmreg),
4784 emit_move_insn (parmreg, DECL_RTL (parm));
4785 conversion_insns = get_insns();
4790 emit_move_insn (parmreg, DECL_RTL (parm));
4791 SET_DECL_RTL (parm, parmreg);
4792 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4796 #ifdef FUNCTION_ARG_CALLEE_COPIES
4797 /* If we are passed an arg by reference and it is our responsibility
4798 to make a copy, do it now.
4799 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4800 original argument, so we must recreate them in the call to
4801 FUNCTION_ARG_CALLEE_COPIES. */
4802 /* ??? Later add code to handle the case that if the argument isn't
4803 modified, don't do the copy. */
4805 else if (passed_pointer
4806 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4807 TYPE_MODE (DECL_ARG_TYPE (parm)),
4808 DECL_ARG_TYPE (parm),
4810 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4813 tree type = DECL_ARG_TYPE (parm);
4815 /* This sequence may involve a library call perhaps clobbering
4816 registers that haven't been copied to pseudos yet. */
4818 push_to_sequence (conversion_insns);
4820 if (!COMPLETE_TYPE_P (type)
4821 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4822 /* This is a variable sized object. */
4823 copy = gen_rtx_MEM (BLKmode,
4824 allocate_dynamic_stack_space
4825 (expr_size (parm), NULL_RTX,
4826 TYPE_ALIGN (type)));
4828 copy = assign_stack_temp (TYPE_MODE (type),
4829 int_size_in_bytes (type), 1);
4830 set_mem_attributes (copy, parm, 1);
4832 store_expr (parm, copy, 0);
4833 emit_move_insn (parmreg, XEXP (copy, 0));
4834 if (current_function_check_memory_usage)
4835 emit_library_call (chkr_set_right_libfunc,
4836 LCT_CONST_MAKE_BLOCK, VOIDmode, 3,
4837 XEXP (copy, 0), Pmode,
4838 GEN_INT (int_size_in_bytes (type)),
4839 TYPE_MODE (sizetype),
4840 GEN_INT (MEMORY_USE_RW),
4841 TYPE_MODE (integer_type_node));
4842 conversion_insns = get_insns ();
4846 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4848 /* In any case, record the parm's desired stack location
4849 in case we later discover it must live in the stack.
4851 If it is a COMPLEX value, store the stack location for both
4854 if (GET_CODE (parmreg) == CONCAT)
4855 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4857 regno = REGNO (parmreg);
4859 if (regno >= max_parm_reg)
4862 int old_max_parm_reg = max_parm_reg;
4864 /* It's slow to expand this one register at a time,
4865 but it's also rare and we need max_parm_reg to be
4866 precisely correct. */
4867 max_parm_reg = regno + 1;
4868 new = (rtx *) xrealloc (parm_reg_stack_loc,
4869 max_parm_reg * sizeof (rtx));
4870 memset ((char *) (new + old_max_parm_reg), 0,
4871 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4872 parm_reg_stack_loc = new;
4875 if (GET_CODE (parmreg) == CONCAT)
4877 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
4879 regnor = REGNO (gen_realpart (submode, parmreg));
4880 regnoi = REGNO (gen_imagpart (submode, parmreg));
4882 if (stack_parm != 0)
4884 parm_reg_stack_loc[regnor]
4885 = gen_realpart (submode, stack_parm);
4886 parm_reg_stack_loc[regnoi]
4887 = gen_imagpart (submode, stack_parm);
4891 parm_reg_stack_loc[regnor] = 0;
4892 parm_reg_stack_loc[regnoi] = 0;
4896 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
4898 /* Mark the register as eliminable if we did no conversion
4899 and it was copied from memory at a fixed offset,
4900 and the arg pointer was not copied to a pseudo-reg.
4901 If the arg pointer is a pseudo reg or the offset formed
4902 an invalid address, such memory-equivalences
4903 as we make here would screw up life analysis for it. */
4904 if (nominal_mode == passed_mode
4907 && GET_CODE (stack_parm) == MEM
4908 && stack_offset.var == 0
4909 && reg_mentioned_p (virtual_incoming_args_rtx,
4910 XEXP (stack_parm, 0)))
4912 rtx linsn = get_last_insn ();
4915 /* Mark complex types separately. */
4916 if (GET_CODE (parmreg) == CONCAT)
4917 /* Scan backwards for the set of the real and
4919 for (sinsn = linsn; sinsn != 0;
4920 sinsn = prev_nonnote_insn (sinsn))
4922 set = single_set (sinsn);
4924 && SET_DEST (set) == regno_reg_rtx [regnoi])
4926 = gen_rtx_EXPR_LIST (REG_EQUIV,
4927 parm_reg_stack_loc[regnoi],
4930 && SET_DEST (set) == regno_reg_rtx [regnor])
4932 = gen_rtx_EXPR_LIST (REG_EQUIV,
4933 parm_reg_stack_loc[regnor],
4936 else if ((set = single_set (linsn)) != 0
4937 && SET_DEST (set) == parmreg)
4939 = gen_rtx_EXPR_LIST (REG_EQUIV,
4940 stack_parm, REG_NOTES (linsn));
4943 /* For pointer data type, suggest pointer register. */
4944 if (POINTER_TYPE_P (TREE_TYPE (parm)))
4945 mark_reg_pointer (parmreg,
4946 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
4948 /* If something wants our address, try to use ADDRESSOF. */
4949 if (TREE_ADDRESSABLE (parm))
4951 /* If we end up putting something into the stack,
4952 fixup_var_refs_insns will need to make a pass over
4953 all the instructions. It looks throughs the pending
4954 sequences -- but it can't see the ones in the
4955 CONVERSION_INSNS, if they're not on the sequence
4956 stack. So, we go back to that sequence, just so that
4957 the fixups will happen. */
4958 push_to_sequence (conversion_insns);
4959 put_var_into_stack (parm);
4960 conversion_insns = get_insns ();
4966 /* Value must be stored in the stack slot STACK_PARM
4967 during function execution. */
4969 if (promoted_mode != nominal_mode)
4971 /* Conversion is required. */
4972 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4974 emit_move_insn (tempreg, validize_mem (entry_parm));
4976 push_to_sequence (conversion_insns);
4977 entry_parm = convert_to_mode (nominal_mode, tempreg,
4978 TREE_UNSIGNED (TREE_TYPE (parm)));
4980 /* ??? This may need a big-endian conversion on sparc64. */
4981 stack_parm = adjust_address (stack_parm, nominal_mode, 0);
4983 conversion_insns = get_insns ();
4988 if (entry_parm != stack_parm)
4990 if (stack_parm == 0)
4993 = assign_stack_local (GET_MODE (entry_parm),
4994 GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
4995 set_mem_attributes (stack_parm, parm, 1);
4998 if (promoted_mode != nominal_mode)
5000 push_to_sequence (conversion_insns);
5001 emit_move_insn (validize_mem (stack_parm),
5002 validize_mem (entry_parm));
5003 conversion_insns = get_insns ();
5007 emit_move_insn (validize_mem (stack_parm),
5008 validize_mem (entry_parm));
5010 if (current_function_check_memory_usage)
5012 push_to_sequence (conversion_insns);
5013 emit_library_call (chkr_set_right_libfunc, LCT_CONST_MAKE_BLOCK,
5014 VOIDmode, 3, XEXP (stack_parm, 0), Pmode,
5015 GEN_INT (GET_MODE_SIZE (GET_MODE
5017 TYPE_MODE (sizetype),
5018 GEN_INT (MEMORY_USE_RW),
5019 TYPE_MODE (integer_type_node));
5021 conversion_insns = get_insns ();
5024 SET_DECL_RTL (parm, stack_parm);
5027 /* If this "parameter" was the place where we are receiving the
5028 function's incoming structure pointer, set up the result. */
5029 if (parm == function_result_decl)
5031 tree result = DECL_RESULT (fndecl);
5033 SET_DECL_RTL (result,
5034 gen_rtx_MEM (DECL_MODE (result), DECL_RTL (parm)));
5036 set_mem_attributes (DECL_RTL (result), result, 1);
5040 /* Output all parameter conversion instructions (possibly including calls)
5041 now that all parameters have been copied out of hard registers. */
5042 emit_insns (conversion_insns);
5044 last_parm_insn = get_last_insn ();
5046 current_function_args_size = stack_args_size.constant;
5048 /* Adjust function incoming argument size for alignment and
5051 #ifdef REG_PARM_STACK_SPACE
5052 #ifndef MAYBE_REG_PARM_STACK_SPACE
5053 current_function_args_size = MAX (current_function_args_size,
5054 REG_PARM_STACK_SPACE (fndecl));
5058 #ifdef STACK_BOUNDARY
5059 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
5061 current_function_args_size
5062 = ((current_function_args_size + STACK_BYTES - 1)
5063 / STACK_BYTES) * STACK_BYTES;
5066 #ifdef ARGS_GROW_DOWNWARD
5067 current_function_arg_offset_rtx
5068 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
5069 : expand_expr (size_diffop (stack_args_size.var,
5070 size_int (-stack_args_size.constant)),
5071 NULL_RTX, VOIDmode, EXPAND_MEMORY_USE_BAD));
5073 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
5076 /* See how many bytes, if any, of its args a function should try to pop
5079 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
5080 current_function_args_size);
5082 /* For stdarg.h function, save info about
5083 regs and stack space used by the named args. */
5086 current_function_args_info = args_so_far;
5088 /* Set the rtx used for the function return value. Put this in its
5089 own variable so any optimizers that need this information don't have
5090 to include tree.h. Do this here so it gets done when an inlined
5091 function gets output. */
5093 current_function_return_rtx
5094 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
5095 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
5098 /* Indicate whether REGNO is an incoming argument to the current function
5099 that was promoted to a wider mode. If so, return the RTX for the
5100 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5101 that REGNO is promoted from and whether the promotion was signed or
5104 #ifdef PROMOTE_FUNCTION_ARGS
5107 promoted_input_arg (regno, pmode, punsignedp)
5109 enum machine_mode *pmode;
5114 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
5115 arg = TREE_CHAIN (arg))
5116 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
5117 && REGNO (DECL_INCOMING_RTL (arg)) == regno
5118 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
5120 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
5121 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
5123 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
5124 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
5125 && mode != DECL_MODE (arg))
5127 *pmode = DECL_MODE (arg);
5128 *punsignedp = unsignedp;
5129 return DECL_INCOMING_RTL (arg);
5138 /* Compute the size and offset from the start of the stacked arguments for a
5139 parm passed in mode PASSED_MODE and with type TYPE.
5141 INITIAL_OFFSET_PTR points to the current offset into the stacked
5144 The starting offset and size for this parm are returned in *OFFSET_PTR
5145 and *ARG_SIZE_PTR, respectively.
5147 IN_REGS is non-zero if the argument will be passed in registers. It will
5148 never be set if REG_PARM_STACK_SPACE is not defined.
5150 FNDECL is the function in which the argument was defined.
5152 There are two types of rounding that are done. The first, controlled by
5153 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5154 list to be aligned to the specific boundary (in bits). This rounding
5155 affects the initial and starting offsets, but not the argument size.
5157 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5158 optionally rounds the size of the parm to PARM_BOUNDARY. The
5159 initial offset is not affected by this rounding, while the size always
5160 is and the starting offset may be. */
5162 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
5163 initial_offset_ptr is positive because locate_and_pad_parm's
5164 callers pass in the total size of args so far as
5165 initial_offset_ptr. arg_size_ptr is always positive.*/
5168 locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
5169 initial_offset_ptr, offset_ptr, arg_size_ptr,
5171 enum machine_mode passed_mode;
5173 int in_regs ATTRIBUTE_UNUSED;
5174 tree fndecl ATTRIBUTE_UNUSED;
5175 struct args_size *initial_offset_ptr;
5176 struct args_size *offset_ptr;
5177 struct args_size *arg_size_ptr;
5178 struct args_size *alignment_pad;
5182 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5183 enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5184 int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5186 #ifdef REG_PARM_STACK_SPACE
5187 /* If we have found a stack parm before we reach the end of the
5188 area reserved for registers, skip that area. */
5191 int reg_parm_stack_space = 0;
5193 #ifdef MAYBE_REG_PARM_STACK_SPACE
5194 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
5196 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5198 if (reg_parm_stack_space > 0)
5200 if (initial_offset_ptr->var)
5202 initial_offset_ptr->var
5203 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5204 ssize_int (reg_parm_stack_space));
5205 initial_offset_ptr->constant = 0;
5207 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5208 initial_offset_ptr->constant = reg_parm_stack_space;
5211 #endif /* REG_PARM_STACK_SPACE */
5213 arg_size_ptr->var = 0;
5214 arg_size_ptr->constant = 0;
5215 alignment_pad->var = 0;
5216 alignment_pad->constant = 0;
5218 #ifdef ARGS_GROW_DOWNWARD
5219 if (initial_offset_ptr->var)
5221 offset_ptr->constant = 0;
5222 offset_ptr->var = size_binop (MINUS_EXPR, ssize_int (0),
5223 initial_offset_ptr->var);
5227 offset_ptr->constant = -initial_offset_ptr->constant;
5228 offset_ptr->var = 0;
5230 if (where_pad != none
5231 && (!host_integerp (sizetree, 1)
5232 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5233 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5234 SUB_PARM_SIZE (*offset_ptr, sizetree);
5235 if (where_pad != downward)
5236 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad);
5237 if (initial_offset_ptr->var)
5238 arg_size_ptr->var = size_binop (MINUS_EXPR,
5239 size_binop (MINUS_EXPR,
5241 initial_offset_ptr->var),
5245 arg_size_ptr->constant = (-initial_offset_ptr->constant
5246 - offset_ptr->constant);
5248 #else /* !ARGS_GROW_DOWNWARD */
5250 #ifdef REG_PARM_STACK_SPACE
5251 || REG_PARM_STACK_SPACE (fndecl) > 0
5254 pad_to_arg_alignment (initial_offset_ptr, boundary, alignment_pad);
5255 *offset_ptr = *initial_offset_ptr;
5257 #ifdef PUSH_ROUNDING
5258 if (passed_mode != BLKmode)
5259 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5262 /* Pad_below needs the pre-rounded size to know how much to pad below
5263 so this must be done before rounding up. */
5264 if (where_pad == downward
5265 /* However, BLKmode args passed in regs have their padding done elsewhere.
5266 The stack slot must be able to hold the entire register. */
5267 && !(in_regs && passed_mode == BLKmode))
5268 pad_below (offset_ptr, passed_mode, sizetree);
5270 if (where_pad != none
5271 && (!host_integerp (sizetree, 1)
5272 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5273 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5275 ADD_PARM_SIZE (*arg_size_ptr, sizetree);
5276 #endif /* ARGS_GROW_DOWNWARD */
5279 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5280 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5283 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad)
5284 struct args_size *offset_ptr;
5286 struct args_size *alignment_pad;
5288 tree save_var = NULL_TREE;
5289 HOST_WIDE_INT save_constant = 0;
5291 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5293 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5295 save_var = offset_ptr->var;
5296 save_constant = offset_ptr->constant;
5299 alignment_pad->var = NULL_TREE;
5300 alignment_pad->constant = 0;
5302 if (boundary > BITS_PER_UNIT)
5304 if (offset_ptr->var)
5307 #ifdef ARGS_GROW_DOWNWARD
5312 (ARGS_SIZE_TREE (*offset_ptr),
5313 boundary / BITS_PER_UNIT);
5314 offset_ptr->constant = 0; /*?*/
5315 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5316 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5321 offset_ptr->constant =
5322 #ifdef ARGS_GROW_DOWNWARD
5323 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
5325 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
5327 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5328 alignment_pad->constant = offset_ptr->constant - save_constant;
5333 #ifndef ARGS_GROW_DOWNWARD
5335 pad_below (offset_ptr, passed_mode, sizetree)
5336 struct args_size *offset_ptr;
5337 enum machine_mode passed_mode;
5340 if (passed_mode != BLKmode)
5342 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5343 offset_ptr->constant
5344 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5345 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5346 - GET_MODE_SIZE (passed_mode));
5350 if (TREE_CODE (sizetree) != INTEGER_CST
5351 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5353 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5354 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5356 ADD_PARM_SIZE (*offset_ptr, s2);
5357 SUB_PARM_SIZE (*offset_ptr, sizetree);
5363 /* Walk the tree of blocks describing the binding levels within a function
5364 and warn about uninitialized variables.
5365 This is done after calling flow_analysis and before global_alloc
5366 clobbers the pseudo-regs to hard regs. */
5369 uninitialized_vars_warning (block)
5372 register tree decl, sub;
5373 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5375 if (warn_uninitialized
5376 && TREE_CODE (decl) == VAR_DECL
5377 /* These warnings are unreliable for and aggregates
5378 because assigning the fields one by one can fail to convince
5379 flow.c that the entire aggregate was initialized.
5380 Unions are troublesome because members may be shorter. */
5381 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5382 && DECL_RTL (decl) != 0
5383 && GET_CODE (DECL_RTL (decl)) == REG
5384 /* Global optimizations can make it difficult to determine if a
5385 particular variable has been initialized. However, a VAR_DECL
5386 with a nonzero DECL_INITIAL had an initializer, so do not
5387 claim it is potentially uninitialized.
5389 We do not care about the actual value in DECL_INITIAL, so we do
5390 not worry that it may be a dangling pointer. */
5391 && DECL_INITIAL (decl) == NULL_TREE
5392 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5393 warning_with_decl (decl,
5394 "`%s' might be used uninitialized in this function");
5396 && TREE_CODE (decl) == VAR_DECL
5397 && DECL_RTL (decl) != 0
5398 && GET_CODE (DECL_RTL (decl)) == REG
5399 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5400 warning_with_decl (decl,
5401 "variable `%s' might be clobbered by `longjmp' or `vfork'");
5403 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5404 uninitialized_vars_warning (sub);
5407 /* Do the appropriate part of uninitialized_vars_warning
5408 but for arguments instead of local variables. */
5411 setjmp_args_warning ()
5414 for (decl = DECL_ARGUMENTS (current_function_decl);
5415 decl; decl = TREE_CHAIN (decl))
5416 if (DECL_RTL (decl) != 0
5417 && GET_CODE (DECL_RTL (decl)) == REG
5418 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5419 warning_with_decl (decl,
5420 "argument `%s' might be clobbered by `longjmp' or `vfork'");
5423 /* If this function call setjmp, put all vars into the stack
5424 unless they were declared `register'. */
5427 setjmp_protect (block)
5430 register tree decl, sub;
5431 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5432 if ((TREE_CODE (decl) == VAR_DECL
5433 || TREE_CODE (decl) == PARM_DECL)
5434 && DECL_RTL (decl) != 0
5435 && (GET_CODE (DECL_RTL (decl)) == REG
5436 || (GET_CODE (DECL_RTL (decl)) == MEM
5437 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5438 /* If this variable came from an inline function, it must be
5439 that its life doesn't overlap the setjmp. If there was a
5440 setjmp in the function, it would already be in memory. We
5441 must exclude such variable because their DECL_RTL might be
5442 set to strange things such as virtual_stack_vars_rtx. */
5443 && ! DECL_FROM_INLINE (decl)
5445 #ifdef NON_SAVING_SETJMP
5446 /* If longjmp doesn't restore the registers,
5447 don't put anything in them. */
5451 ! DECL_REGISTER (decl)))
5452 put_var_into_stack (decl);
5453 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5454 setjmp_protect (sub);
5457 /* Like the previous function, but for args instead of local variables. */
5460 setjmp_protect_args ()
5463 for (decl = DECL_ARGUMENTS (current_function_decl);
5464 decl; decl = TREE_CHAIN (decl))
5465 if ((TREE_CODE (decl) == VAR_DECL
5466 || TREE_CODE (decl) == PARM_DECL)
5467 && DECL_RTL (decl) != 0
5468 && (GET_CODE (DECL_RTL (decl)) == REG
5469 || (GET_CODE (DECL_RTL (decl)) == MEM
5470 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5472 /* If longjmp doesn't restore the registers,
5473 don't put anything in them. */
5474 #ifdef NON_SAVING_SETJMP
5478 ! DECL_REGISTER (decl)))
5479 put_var_into_stack (decl);
5482 /* Return the context-pointer register corresponding to DECL,
5483 or 0 if it does not need one. */
5486 lookup_static_chain (decl)
5489 tree context = decl_function_context (decl);
5493 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5496 /* We treat inline_function_decl as an alias for the current function
5497 because that is the inline function whose vars, types, etc.
5498 are being merged into the current function.
5499 See expand_inline_function. */
5500 if (context == current_function_decl || context == inline_function_decl)
5501 return virtual_stack_vars_rtx;
5503 for (link = context_display; link; link = TREE_CHAIN (link))
5504 if (TREE_PURPOSE (link) == context)
5505 return RTL_EXPR_RTL (TREE_VALUE (link));
5510 /* Convert a stack slot address ADDR for variable VAR
5511 (from a containing function)
5512 into an address valid in this function (using a static chain). */
5515 fix_lexical_addr (addr, var)
5520 HOST_WIDE_INT displacement;
5521 tree context = decl_function_context (var);
5522 struct function *fp;
5525 /* If this is the present function, we need not do anything. */
5526 if (context == current_function_decl || context == inline_function_decl)
5529 for (fp = outer_function_chain; fp; fp = fp->next)
5530 if (fp->decl == context)
5536 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5537 addr = XEXP (XEXP (addr, 0), 0);
5539 /* Decode given address as base reg plus displacement. */
5540 if (GET_CODE (addr) == REG)
5541 basereg = addr, displacement = 0;
5542 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5543 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5547 /* We accept vars reached via the containing function's
5548 incoming arg pointer and via its stack variables pointer. */
5549 if (basereg == fp->internal_arg_pointer)
5551 /* If reached via arg pointer, get the arg pointer value
5552 out of that function's stack frame.
5554 There are two cases: If a separate ap is needed, allocate a
5555 slot in the outer function for it and dereference it that way.
5556 This is correct even if the real ap is actually a pseudo.
5557 Otherwise, just adjust the offset from the frame pointer to
5560 #ifdef NEED_SEPARATE_AP
5563 if (fp->x_arg_pointer_save_area == 0)
5564 fp->x_arg_pointer_save_area
5565 = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, fp);
5567 addr = fix_lexical_addr (XEXP (fp->x_arg_pointer_save_area, 0), var);
5568 addr = memory_address (Pmode, addr);
5570 base = gen_rtx_MEM (Pmode, addr);
5571 MEM_ALIAS_SET (base) = get_frame_alias_set ();
5572 base = copy_to_reg (base);
5574 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5575 base = lookup_static_chain (var);
5579 else if (basereg == virtual_stack_vars_rtx)
5581 /* This is the same code as lookup_static_chain, duplicated here to
5582 avoid an extra call to decl_function_context. */
5585 for (link = context_display; link; link = TREE_CHAIN (link))
5586 if (TREE_PURPOSE (link) == context)
5588 base = RTL_EXPR_RTL (TREE_VALUE (link));
5596 /* Use same offset, relative to appropriate static chain or argument
5598 return plus_constant (base, displacement);
5601 /* Return the address of the trampoline for entering nested fn FUNCTION.
5602 If necessary, allocate a trampoline (in the stack frame)
5603 and emit rtl to initialize its contents (at entry to this function). */
5606 trampoline_address (function)
5612 struct function *fp;
5615 /* Find an existing trampoline and return it. */
5616 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5617 if (TREE_PURPOSE (link) == function)
5619 adjust_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5621 for (fp = outer_function_chain; fp; fp = fp->next)
5622 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5623 if (TREE_PURPOSE (link) == function)
5625 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5627 return adjust_trampoline_addr (tramp);
5630 /* None exists; we must make one. */
5632 /* Find the `struct function' for the function containing FUNCTION. */
5634 fn_context = decl_function_context (function);
5635 if (fn_context != current_function_decl
5636 && fn_context != inline_function_decl)
5637 for (fp = outer_function_chain; fp; fp = fp->next)
5638 if (fp->decl == fn_context)
5641 /* Allocate run-time space for this trampoline
5642 (usually in the defining function's stack frame). */
5643 #ifdef ALLOCATE_TRAMPOLINE
5644 tramp = ALLOCATE_TRAMPOLINE (fp);
5646 /* If rounding needed, allocate extra space
5647 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5648 #ifdef TRAMPOLINE_ALIGNMENT
5649 #define TRAMPOLINE_REAL_SIZE \
5650 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5652 #define TRAMPOLINE_REAL_SIZE (TRAMPOLINE_SIZE)
5654 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5658 /* Record the trampoline for reuse and note it for later initialization
5659 by expand_function_end. */
5662 rtlexp = make_node (RTL_EXPR);
5663 RTL_EXPR_RTL (rtlexp) = tramp;
5664 fp->x_trampoline_list = tree_cons (function, rtlexp,
5665 fp->x_trampoline_list);
5669 /* Make the RTL_EXPR node temporary, not momentary, so that the
5670 trampoline_list doesn't become garbage. */
5671 rtlexp = make_node (RTL_EXPR);
5673 RTL_EXPR_RTL (rtlexp) = tramp;
5674 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5677 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5678 return adjust_trampoline_addr (tramp);
5681 /* Given a trampoline address,
5682 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5685 round_trampoline_addr (tramp)
5688 #ifdef TRAMPOLINE_ALIGNMENT
5689 /* Round address up to desired boundary. */
5690 rtx temp = gen_reg_rtx (Pmode);
5691 temp = expand_binop (Pmode, add_optab, tramp,
5692 GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1),
5693 temp, 0, OPTAB_LIB_WIDEN);
5694 tramp = expand_binop (Pmode, and_optab, temp,
5695 GEN_INT (-TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT),
5696 temp, 0, OPTAB_LIB_WIDEN);
5701 /* Given a trampoline address, round it then apply any
5702 platform-specific adjustments so that the result can be used for a
5706 adjust_trampoline_addr (tramp)
5709 tramp = round_trampoline_addr (tramp);
5710 #ifdef TRAMPOLINE_ADJUST_ADDRESS
5711 TRAMPOLINE_ADJUST_ADDRESS (tramp);
5716 /* Put all this function's BLOCK nodes including those that are chained
5717 onto the first block into a vector, and return it.
5718 Also store in each NOTE for the beginning or end of a block
5719 the index of that block in the vector.
5720 The arguments are BLOCK, the chain of top-level blocks of the function,
5721 and INSNS, the insn chain of the function. */
5727 tree *block_vector, *last_block_vector;
5729 tree block = DECL_INITIAL (current_function_decl);
5734 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5735 depth-first order. */
5736 block_vector = get_block_vector (block, &n_blocks);
5737 block_stack = (tree *) xmalloc (n_blocks * sizeof (tree));
5739 last_block_vector = identify_blocks_1 (get_insns (),
5741 block_vector + n_blocks,
5744 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5745 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5746 if (0 && last_block_vector != block_vector + n_blocks)
5749 free (block_vector);
5753 /* Subroutine of identify_blocks. Do the block substitution on the
5754 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
5756 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5757 BLOCK_VECTOR is incremented for each block seen. */
5760 identify_blocks_1 (insns, block_vector, end_block_vector, orig_block_stack)
5763 tree *end_block_vector;
5764 tree *orig_block_stack;
5767 tree *block_stack = orig_block_stack;
5769 for (insn = insns; insn; insn = NEXT_INSN (insn))
5771 if (GET_CODE (insn) == NOTE)
5773 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5777 /* If there are more block notes than BLOCKs, something
5779 if (block_vector == end_block_vector)
5782 b = *block_vector++;
5783 NOTE_BLOCK (insn) = b;
5786 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5788 /* If there are more NOTE_INSN_BLOCK_ENDs than
5789 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
5790 if (block_stack == orig_block_stack)
5793 NOTE_BLOCK (insn) = *--block_stack;
5796 else if (GET_CODE (insn) == CALL_INSN
5797 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5799 rtx cp = PATTERN (insn);
5801 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
5802 end_block_vector, block_stack);
5804 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
5805 end_block_vector, block_stack);
5807 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
5808 end_block_vector, block_stack);
5812 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
5813 something is badly wrong. */
5814 if (block_stack != orig_block_stack)
5817 return block_vector;
5820 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
5821 and create duplicate blocks. */
5822 /* ??? Need an option to either create block fragments or to create
5823 abstract origin duplicates of a source block. It really depends
5824 on what optimization has been performed. */
5829 tree block = DECL_INITIAL (current_function_decl);
5830 varray_type block_stack;
5832 if (block == NULL_TREE)
5835 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
5837 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
5838 reorder_blocks_0 (block);
5840 /* Prune the old trees away, so that they don't get in the way. */
5841 BLOCK_SUBBLOCKS (block) = NULL_TREE;
5842 BLOCK_CHAIN (block) = NULL_TREE;
5844 /* Recreate the block tree from the note nesting. */
5845 reorder_blocks_1 (get_insns (), block, &block_stack);
5846 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
5848 /* Remove deleted blocks from the block fragment chains. */
5849 reorder_fix_fragments (block);
5851 VARRAY_FREE (block_stack);
5854 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
5857 reorder_blocks_0 (block)
5862 TREE_ASM_WRITTEN (block) = 0;
5863 reorder_blocks_0 (BLOCK_SUBBLOCKS (block));
5864 block = BLOCK_CHAIN (block);
5869 reorder_blocks_1 (insns, current_block, p_block_stack)
5872 varray_type *p_block_stack;
5876 for (insn = insns; insn; insn = NEXT_INSN (insn))
5878 if (GET_CODE (insn) == NOTE)
5880 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5882 tree block = NOTE_BLOCK (insn);
5884 /* If we have seen this block before, that means it now
5885 spans multiple address regions. Create a new fragment. */
5886 if (TREE_ASM_WRITTEN (block))
5888 tree new_block = copy_node (block);
5891 origin = (BLOCK_FRAGMENT_ORIGIN (block)
5892 ? BLOCK_FRAGMENT_ORIGIN (block)
5894 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
5895 BLOCK_FRAGMENT_CHAIN (new_block)
5896 = BLOCK_FRAGMENT_CHAIN (origin);
5897 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
5899 NOTE_BLOCK (insn) = new_block;
5903 BLOCK_SUBBLOCKS (block) = 0;
5904 TREE_ASM_WRITTEN (block) = 1;
5905 BLOCK_SUPERCONTEXT (block) = current_block;
5906 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
5907 BLOCK_SUBBLOCKS (current_block) = block;
5908 current_block = block;
5909 VARRAY_PUSH_TREE (*p_block_stack, block);
5911 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5913 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
5914 VARRAY_POP (*p_block_stack);
5915 BLOCK_SUBBLOCKS (current_block)
5916 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5917 current_block = BLOCK_SUPERCONTEXT (current_block);
5920 else if (GET_CODE (insn) == CALL_INSN
5921 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5923 rtx cp = PATTERN (insn);
5924 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
5926 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
5928 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
5933 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
5934 appears in the block tree, select one of the fragments to become
5935 the new origin block. */
5938 reorder_fix_fragments (block)
5943 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
5944 tree new_origin = NULL_TREE;
5948 if (! TREE_ASM_WRITTEN (dup_origin))
5950 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
5952 /* Find the first of the remaining fragments. There must
5953 be at least one -- the current block. */
5954 while (! TREE_ASM_WRITTEN (new_origin))
5955 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
5956 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
5959 else if (! dup_origin)
5962 /* Re-root the rest of the fragments to the new origin. In the
5963 case that DUP_ORIGIN was null, that means BLOCK was the origin
5964 of a chain of fragments and we want to remove those fragments
5965 that didn't make it to the output. */
5968 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
5973 if (TREE_ASM_WRITTEN (chain))
5975 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
5977 pp = &BLOCK_FRAGMENT_CHAIN (chain);
5979 chain = BLOCK_FRAGMENT_CHAIN (chain);
5984 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
5985 block = BLOCK_CHAIN (block);
5989 /* Reverse the order of elements in the chain T of blocks,
5990 and return the new head of the chain (old last element). */
5996 register tree prev = 0, decl, next;
5997 for (decl = t; decl; decl = next)
5999 next = BLOCK_CHAIN (decl);
6000 BLOCK_CHAIN (decl) = prev;
6006 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
6007 non-NULL, list them all into VECTOR, in a depth-first preorder
6008 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
6012 all_blocks (block, vector)
6020 TREE_ASM_WRITTEN (block) = 0;
6022 /* Record this block. */
6024 vector[n_blocks] = block;
6028 /* Record the subblocks, and their subblocks... */
6029 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
6030 vector ? vector + n_blocks : 0);
6031 block = BLOCK_CHAIN (block);
6037 /* Return a vector containing all the blocks rooted at BLOCK. The
6038 number of elements in the vector is stored in N_BLOCKS_P. The
6039 vector is dynamically allocated; it is the caller's responsibility
6040 to call `free' on the pointer returned. */
6043 get_block_vector (block, n_blocks_p)
6049 *n_blocks_p = all_blocks (block, NULL);
6050 block_vector = (tree *) xmalloc (*n_blocks_p * sizeof (tree));
6051 all_blocks (block, block_vector);
6053 return block_vector;
6056 static int next_block_index = 2;
6058 /* Set BLOCK_NUMBER for all the blocks in FN. */
6068 /* For SDB and XCOFF debugging output, we start numbering the blocks
6069 from 1 within each function, rather than keeping a running
6071 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6072 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
6073 next_block_index = 1;
6076 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
6078 /* The top-level BLOCK isn't numbered at all. */
6079 for (i = 1; i < n_blocks; ++i)
6080 /* We number the blocks from two. */
6081 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
6083 free (block_vector);
6088 /* Allocate a function structure and reset its contents to the defaults. */
6090 prepare_function_start ()
6092 cfun = (struct function *) xcalloc (1, sizeof (struct function));
6094 init_stmt_for_function ();
6095 init_eh_for_function ();
6097 cse_not_expected = ! optimize;
6099 /* Caller save not needed yet. */
6100 caller_save_needed = 0;
6102 /* No stack slots have been made yet. */
6103 stack_slot_list = 0;
6105 current_function_has_nonlocal_label = 0;
6106 current_function_has_nonlocal_goto = 0;
6108 /* There is no stack slot for handling nonlocal gotos. */
6109 nonlocal_goto_handler_slots = 0;
6110 nonlocal_goto_stack_level = 0;
6112 /* No labels have been declared for nonlocal use. */
6113 nonlocal_labels = 0;
6114 nonlocal_goto_handler_labels = 0;
6116 /* No function calls so far in this function. */
6117 function_call_count = 0;
6119 /* No parm regs have been allocated.
6120 (This is important for output_inline_function.) */
6121 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
6123 /* Initialize the RTL mechanism. */
6126 /* Initialize the queue of pending postincrement and postdecrements,
6127 and some other info in expr.c. */
6130 /* We haven't done register allocation yet. */
6133 init_varasm_status (cfun);
6135 /* Clear out data used for inlining. */
6136 cfun->inlinable = 0;
6137 cfun->original_decl_initial = 0;
6138 cfun->original_arg_vector = 0;
6140 #ifdef STACK_BOUNDARY
6141 cfun->stack_alignment_needed = STACK_BOUNDARY;
6142 cfun->preferred_stack_boundary = STACK_BOUNDARY;
6144 cfun->stack_alignment_needed = 0;
6145 cfun->preferred_stack_boundary = 0;
6148 /* Set if a call to setjmp is seen. */
6149 current_function_calls_setjmp = 0;
6151 /* Set if a call to longjmp is seen. */
6152 current_function_calls_longjmp = 0;
6154 current_function_calls_alloca = 0;
6155 current_function_contains_functions = 0;
6156 current_function_is_leaf = 0;
6157 current_function_nothrow = 0;
6158 current_function_sp_is_unchanging = 0;
6159 current_function_uses_only_leaf_regs = 0;
6160 current_function_has_computed_jump = 0;
6161 current_function_is_thunk = 0;
6163 current_function_returns_pcc_struct = 0;
6164 current_function_returns_struct = 0;
6165 current_function_epilogue_delay_list = 0;
6166 current_function_uses_const_pool = 0;
6167 current_function_uses_pic_offset_table = 0;
6168 current_function_cannot_inline = 0;
6170 /* We have not yet needed to make a label to jump to for tail-recursion. */
6171 tail_recursion_label = 0;
6173 /* We haven't had a need to make a save area for ap yet. */
6174 arg_pointer_save_area = 0;
6176 /* No stack slots allocated yet. */
6179 /* No SAVE_EXPRs in this function yet. */
6182 /* No RTL_EXPRs in this function yet. */
6185 /* Set up to allocate temporaries. */
6188 /* Indicate that we need to distinguish between the return value of the
6189 present function and the return value of a function being called. */
6190 rtx_equal_function_value_matters = 1;
6192 /* Indicate that we have not instantiated virtual registers yet. */
6193 virtuals_instantiated = 0;
6195 /* Indicate that we want CONCATs now. */
6196 generating_concat_p = 1;
6198 /* Indicate we have no need of a frame pointer yet. */
6199 frame_pointer_needed = 0;
6201 /* By default assume not varargs or stdarg. */
6202 current_function_varargs = 0;
6203 current_function_stdarg = 0;
6205 /* We haven't made any trampolines for this function yet. */
6206 trampoline_list = 0;
6208 init_pending_stack_adjust ();
6209 inhibit_defer_pop = 0;
6211 current_function_outgoing_args_size = 0;
6213 if (init_lang_status)
6214 (*init_lang_status) (cfun);
6215 if (init_machine_status)
6216 (*init_machine_status) (cfun);
6219 /* Initialize the rtl expansion mechanism so that we can do simple things
6220 like generate sequences. This is used to provide a context during global
6221 initialization of some passes. */
6223 init_dummy_function_start ()
6225 prepare_function_start ();
6228 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6229 and initialize static variables for generating RTL for the statements
6233 init_function_start (subr, filename, line)
6235 const char *filename;
6238 prepare_function_start ();
6240 /* Remember this function for later. */
6241 cfun->next_global = all_functions;
6242 all_functions = cfun;
6244 current_function_name = (*decl_printable_name) (subr, 2);
6247 /* Nonzero if this is a nested function that uses a static chain. */
6249 current_function_needs_context
6250 = (decl_function_context (current_function_decl) != 0
6251 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
6253 /* Within function body, compute a type's size as soon it is laid out. */
6254 immediate_size_expand++;
6256 /* Prevent ever trying to delete the first instruction of a function.
6257 Also tell final how to output a linenum before the function prologue.
6258 Note linenums could be missing, e.g. when compiling a Java .class file. */
6260 emit_line_note (filename, line);
6262 /* Make sure first insn is a note even if we don't want linenums.
6263 This makes sure the first insn will never be deleted.
6264 Also, final expects a note to appear there. */
6265 emit_note (NULL, NOTE_INSN_DELETED);
6267 /* Set flags used by final.c. */
6268 if (aggregate_value_p (DECL_RESULT (subr)))
6270 #ifdef PCC_STATIC_STRUCT_RETURN
6271 current_function_returns_pcc_struct = 1;
6273 current_function_returns_struct = 1;
6276 /* Warn if this value is an aggregate type,
6277 regardless of which calling convention we are using for it. */
6278 if (warn_aggregate_return
6279 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6280 warning ("function returns an aggregate");
6282 current_function_returns_pointer
6283 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
6286 /* Make sure all values used by the optimization passes have sane
6289 init_function_for_compilation ()
6293 /* No prologue/epilogue insns yet. */
6294 VARRAY_GROW (prologue, 0);
6295 VARRAY_GROW (epilogue, 0);
6296 VARRAY_GROW (sibcall_epilogue, 0);
6299 /* Indicate that the current function uses extra args
6300 not explicitly mentioned in the argument list in any fashion. */
6305 current_function_varargs = 1;
6308 /* Expand a call to __main at the beginning of a possible main function. */
6310 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6311 #undef HAS_INIT_SECTION
6312 #define HAS_INIT_SECTION
6316 expand_main_function ()
6318 #if !defined (HAS_INIT_SECTION)
6319 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, NAME__MAIN), 0,
6321 #endif /* not HAS_INIT_SECTION */
6324 extern struct obstack permanent_obstack;
6326 /* The PENDING_SIZES represent the sizes of variable-sized types.
6327 Create RTL for the various sizes now (using temporary variables),
6328 so that we can refer to the sizes from the RTL we are generating
6329 for the current function. The PENDING_SIZES are a TREE_LIST. The
6330 TREE_VALUE of each node is a SAVE_EXPR. */
6333 expand_pending_sizes (pending_sizes)
6338 /* Evaluate now the sizes of any types declared among the arguments. */
6339 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
6341 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode,
6342 EXPAND_MEMORY_USE_BAD);
6343 /* Flush the queue in case this parameter declaration has
6349 /* Start the RTL for a new function, and set variables used for
6351 SUBR is the FUNCTION_DECL node.
6352 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6353 the function's parameters, which must be run at any return statement. */
6356 expand_function_start (subr, parms_have_cleanups)
6358 int parms_have_cleanups;
6361 rtx last_ptr = NULL_RTX;
6363 /* Make sure volatile mem refs aren't considered
6364 valid operands of arithmetic insns. */
6365 init_recog_no_volatile ();
6367 /* Set this before generating any memory accesses. */
6368 current_function_check_memory_usage
6369 = (flag_check_memory_usage
6370 && ! DECL_NO_CHECK_MEMORY_USAGE (current_function_decl));
6372 current_function_instrument_entry_exit
6373 = (flag_instrument_function_entry_exit
6374 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6376 current_function_limit_stack
6377 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6379 /* If function gets a static chain arg, store it in the stack frame.
6380 Do this first, so it gets the first stack slot offset. */
6381 if (current_function_needs_context)
6383 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
6385 /* Delay copying static chain if it is not a register to avoid
6386 conflicts with regs used for parameters. */
6387 if (! SMALL_REGISTER_CLASSES
6388 || GET_CODE (static_chain_incoming_rtx) == REG)
6389 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6392 /* If the parameters of this function need cleaning up, get a label
6393 for the beginning of the code which executes those cleanups. This must
6394 be done before doing anything with return_label. */
6395 if (parms_have_cleanups)
6396 cleanup_label = gen_label_rtx ();
6400 /* Make the label for return statements to jump to. Do not special
6401 case machines with special return instructions -- they will be
6402 handled later during jump, ifcvt, or epilogue creation. */
6403 return_label = gen_label_rtx ();
6405 /* Initialize rtx used to return the value. */
6406 /* Do this before assign_parms so that we copy the struct value address
6407 before any library calls that assign parms might generate. */
6409 /* Decide whether to return the value in memory or in a register. */
6410 if (aggregate_value_p (DECL_RESULT (subr)))
6412 /* Returning something that won't go in a register. */
6413 register rtx value_address = 0;
6415 #ifdef PCC_STATIC_STRUCT_RETURN
6416 if (current_function_returns_pcc_struct)
6418 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6419 value_address = assemble_static_space (size);
6424 /* Expect to be passed the address of a place to store the value.
6425 If it is passed as an argument, assign_parms will take care of
6427 if (struct_value_incoming_rtx)
6429 value_address = gen_reg_rtx (Pmode);
6430 emit_move_insn (value_address, struct_value_incoming_rtx);
6435 SET_DECL_RTL (DECL_RESULT (subr),
6436 gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)),
6438 set_mem_attributes (DECL_RTL (DECL_RESULT (subr)),
6439 DECL_RESULT (subr), 1);
6442 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6443 /* If return mode is void, this decl rtl should not be used. */
6444 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
6447 /* Compute the return values into a pseudo reg, which we will copy
6448 into the true return register after the cleanups are done. */
6450 /* In order to figure out what mode to use for the pseudo, we
6451 figure out what the mode of the eventual return register will
6452 actually be, and use that. */
6454 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
6457 /* Structures that are returned in registers are not aggregate_value_p,
6458 so we may see a PARALLEL. Don't play pseudo games with this. */
6459 if (! REG_P (hard_reg))
6460 SET_DECL_RTL (DECL_RESULT (subr), hard_reg);
6463 /* Create the pseudo. */
6464 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg)));
6466 /* Needed because we may need to move this to memory
6467 in case it's a named return value whose address is taken. */
6468 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6472 /* Initialize rtx for parameters and local variables.
6473 In some cases this requires emitting insns. */
6475 assign_parms (subr);
6477 /* Copy the static chain now if it wasn't a register. The delay is to
6478 avoid conflicts with the parameter passing registers. */
6480 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6481 if (GET_CODE (static_chain_incoming_rtx) != REG)
6482 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6484 /* The following was moved from init_function_start.
6485 The move is supposed to make sdb output more accurate. */
6486 /* Indicate the beginning of the function body,
6487 as opposed to parm setup. */
6488 emit_note (NULL, NOTE_INSN_FUNCTION_BEG);
6490 if (GET_CODE (get_last_insn ()) != NOTE)
6491 emit_note (NULL, NOTE_INSN_DELETED);
6492 parm_birth_insn = get_last_insn ();
6494 context_display = 0;
6495 if (current_function_needs_context)
6497 /* Fetch static chain values for containing functions. */
6498 tem = decl_function_context (current_function_decl);
6499 /* Copy the static chain pointer into a pseudo. If we have
6500 small register classes, copy the value from memory if
6501 static_chain_incoming_rtx is a REG. */
6504 /* If the static chain originally came in a register, put it back
6505 there, then move it out in the next insn. The reason for
6506 this peculiar code is to satisfy function integration. */
6507 if (SMALL_REGISTER_CLASSES
6508 && GET_CODE (static_chain_incoming_rtx) == REG)
6509 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6510 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6515 tree rtlexp = make_node (RTL_EXPR);
6517 RTL_EXPR_RTL (rtlexp) = last_ptr;
6518 context_display = tree_cons (tem, rtlexp, context_display);
6519 tem = decl_function_context (tem);
6522 /* Chain thru stack frames, assuming pointer to next lexical frame
6523 is found at the place we always store it. */
6524 #ifdef FRAME_GROWS_DOWNWARD
6525 last_ptr = plus_constant (last_ptr,
6526 -(HOST_WIDE_INT) GET_MODE_SIZE (Pmode));
6528 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr));
6529 MEM_ALIAS_SET (last_ptr) = get_frame_alias_set ();
6530 last_ptr = copy_to_reg (last_ptr);
6532 /* If we are not optimizing, ensure that we know that this
6533 piece of context is live over the entire function. */
6535 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6540 if (current_function_instrument_entry_exit)
6542 rtx fun = DECL_RTL (current_function_decl);
6543 if (GET_CODE (fun) == MEM)
6544 fun = XEXP (fun, 0);
6547 emit_library_call (profile_function_entry_libfunc, 0, VOIDmode, 2,
6549 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6551 hard_frame_pointer_rtx),
6557 PROFILE_HOOK (profile_label_no);
6560 /* After the display initializations is where the tail-recursion label
6561 should go, if we end up needing one. Ensure we have a NOTE here
6562 since some things (like trampolines) get placed before this. */
6563 tail_recursion_reentry = emit_note (NULL, NOTE_INSN_DELETED);
6565 /* Evaluate now the sizes of any types declared among the arguments. */
6566 expand_pending_sizes (nreverse (get_pending_sizes ()));
6568 /* Make sure there is a line number after the function entry setup code. */
6569 force_next_line_note ();
6572 /* Undo the effects of init_dummy_function_start. */
6574 expand_dummy_function_end ()
6576 /* End any sequences that failed to be closed due to syntax errors. */
6577 while (in_sequence_p ())
6580 /* Outside function body, can't compute type's actual size
6581 until next function's body starts. */
6583 free_after_parsing (cfun);
6584 free_after_compilation (cfun);
6589 /* Call DOIT for each hard register used as a return value from
6590 the current function. */
6593 diddle_return_value (doit, arg)
6594 void (*doit) PARAMS ((rtx, void *));
6597 rtx outgoing = current_function_return_rtx;
6602 if (GET_CODE (outgoing) == REG)
6603 (*doit) (outgoing, arg);
6604 else if (GET_CODE (outgoing) == PARALLEL)
6608 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6610 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6612 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6619 do_clobber_return_reg (reg, arg)
6621 void *arg ATTRIBUTE_UNUSED;
6623 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6627 clobber_return_register ()
6629 diddle_return_value (do_clobber_return_reg, NULL);
6631 /* In case we do use pseudo to return value, clobber it too. */
6632 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6634 tree decl_result = DECL_RESULT (current_function_decl);
6635 rtx decl_rtl = DECL_RTL (decl_result);
6636 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
6638 do_clobber_return_reg (decl_rtl, NULL);
6644 do_use_return_reg (reg, arg)
6646 void *arg ATTRIBUTE_UNUSED;
6648 emit_insn (gen_rtx_USE (VOIDmode, reg));
6652 use_return_register ()
6654 diddle_return_value (do_use_return_reg, NULL);
6657 /* Generate RTL for the end of the current function.
6658 FILENAME and LINE are the current position in the source file.
6660 It is up to language-specific callers to do cleanups for parameters--
6661 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
6664 expand_function_end (filename, line, end_bindings)
6665 const char *filename;
6672 #ifdef TRAMPOLINE_TEMPLATE
6673 static rtx initial_trampoline;
6676 finish_expr_for_function ();
6678 #ifdef NON_SAVING_SETJMP
6679 /* Don't put any variables in registers if we call setjmp
6680 on a machine that fails to restore the registers. */
6681 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6683 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6684 setjmp_protect (DECL_INITIAL (current_function_decl));
6686 setjmp_protect_args ();
6690 /* Save the argument pointer if a save area was made for it. */
6691 if (arg_pointer_save_area)
6693 /* arg_pointer_save_area may not be a valid memory address, so we
6694 have to check it and fix it if necessary. */
6697 emit_move_insn (validize_mem (arg_pointer_save_area),
6698 virtual_incoming_args_rtx);
6699 seq = gen_sequence ();
6701 emit_insn_before (seq, tail_recursion_reentry);
6704 /* Initialize any trampolines required by this function. */
6705 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6707 tree function = TREE_PURPOSE (link);
6708 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6709 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6710 #ifdef TRAMPOLINE_TEMPLATE
6715 #ifdef TRAMPOLINE_TEMPLATE
6716 /* First make sure this compilation has a template for
6717 initializing trampolines. */
6718 if (initial_trampoline == 0)
6721 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6723 ggc_add_rtx_root (&initial_trampoline, 1);
6727 /* Generate insns to initialize the trampoline. */
6729 tramp = round_trampoline_addr (XEXP (tramp, 0));
6730 #ifdef TRAMPOLINE_TEMPLATE
6731 blktramp = change_address (initial_trampoline, BLKmode, tramp);
6732 emit_block_move (blktramp, initial_trampoline,
6733 GEN_INT (TRAMPOLINE_SIZE),
6734 TRAMPOLINE_ALIGNMENT);
6736 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6740 /* Put those insns at entry to the containing function (this one). */
6741 emit_insns_before (seq, tail_recursion_reentry);
6744 /* If we are doing stack checking and this function makes calls,
6745 do a stack probe at the start of the function to ensure we have enough
6746 space for another stack frame. */
6747 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6751 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6752 if (GET_CODE (insn) == CALL_INSN)
6755 probe_stack_range (STACK_CHECK_PROTECT,
6756 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6759 emit_insns_before (seq, tail_recursion_reentry);
6764 /* Warn about unused parms if extra warnings were specified. */
6765 /* Either ``-W -Wunused'' or ``-Wunused-parameter'' enables this
6766 warning. WARN_UNUSED_PARAMETER is negative when set by
6768 if (warn_unused_parameter > 0
6769 || (warn_unused_parameter < 0 && extra_warnings))
6773 for (decl = DECL_ARGUMENTS (current_function_decl);
6774 decl; decl = TREE_CHAIN (decl))
6775 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6776 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6777 warning_with_decl (decl, "unused parameter `%s'");
6780 /* Delete handlers for nonlocal gotos if nothing uses them. */
6781 if (nonlocal_goto_handler_slots != 0
6782 && ! current_function_has_nonlocal_label)
6785 /* End any sequences that failed to be closed due to syntax errors. */
6786 while (in_sequence_p ())
6789 /* Outside function body, can't compute type's actual size
6790 until next function's body starts. */
6791 immediate_size_expand--;
6793 clear_pending_stack_adjust ();
6794 do_pending_stack_adjust ();
6796 /* Mark the end of the function body.
6797 If control reaches this insn, the function can drop through
6798 without returning a value. */
6799 emit_note (NULL, NOTE_INSN_FUNCTION_END);
6801 /* Must mark the last line number note in the function, so that the test
6802 coverage code can avoid counting the last line twice. This just tells
6803 the code to ignore the immediately following line note, since there
6804 already exists a copy of this note somewhere above. This line number
6805 note is still needed for debugging though, so we can't delete it. */
6806 if (flag_test_coverage)
6807 emit_note (NULL, NOTE_INSN_REPEATED_LINE_NUMBER);
6809 /* Output a linenumber for the end of the function.
6810 SDB depends on this. */
6811 emit_line_note_force (filename, line);
6813 /* Before the return label (if any), clobber the return
6814 registers so that they are not propogated live to the rest of
6815 the function. This can only happen with functions that drop
6816 through; if there had been a return statement, there would
6817 have either been a return rtx, or a jump to the return label.
6819 We delay actual code generation after the current_function_value_rtx
6821 clobber_after = get_last_insn ();
6823 /* Output the label for the actual return from the function,
6824 if one is expected. This happens either because a function epilogue
6825 is used instead of a return instruction, or because a return was done
6826 with a goto in order to run local cleanups, or because of pcc-style
6827 structure returning. */
6829 emit_label (return_label);
6831 /* C++ uses this. */
6833 expand_end_bindings (0, 0, 0);
6835 if (current_function_instrument_entry_exit)
6837 rtx fun = DECL_RTL (current_function_decl);
6838 if (GET_CODE (fun) == MEM)
6839 fun = XEXP (fun, 0);
6842 emit_library_call (profile_function_exit_libfunc, 0, VOIDmode, 2,
6844 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6846 hard_frame_pointer_rtx),
6850 /* Let except.c know where it should emit the call to unregister
6851 the function context for sjlj exceptions. */
6852 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
6853 sjlj_emit_function_exit_after (get_last_insn ());
6855 /* If we had calls to alloca, and this machine needs
6856 an accurate stack pointer to exit the function,
6857 insert some code to save and restore the stack pointer. */
6858 #ifdef EXIT_IGNORE_STACK
6859 if (! EXIT_IGNORE_STACK)
6861 if (current_function_calls_alloca)
6865 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
6866 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
6869 /* If scalar return value was computed in a pseudo-reg, or was a named
6870 return value that got dumped to the stack, copy that to the hard
6872 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6874 tree decl_result = DECL_RESULT (current_function_decl);
6875 rtx decl_rtl = DECL_RTL (decl_result);
6877 if (REG_P (decl_rtl)
6878 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
6879 : DECL_REGISTER (decl_result))
6883 #ifdef FUNCTION_OUTGOING_VALUE
6884 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
6885 current_function_decl);
6887 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
6888 current_function_decl);
6890 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
6892 /* If this is a BLKmode structure being returned in registers,
6893 then use the mode computed in expand_return. Note that if
6894 decl_rtl is memory, then its mode may have been changed,
6895 but that current_function_return_rtx has not. */
6896 if (GET_MODE (real_decl_rtl) == BLKmode)
6897 PUT_MODE (real_decl_rtl, GET_MODE (current_function_return_rtx));
6899 /* If a named return value dumped decl_return to memory, then
6900 we may need to re-do the PROMOTE_MODE signed/unsigned
6902 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
6904 int unsignedp = TREE_UNSIGNED (TREE_TYPE (decl_result));
6906 #ifdef PROMOTE_FUNCTION_RETURN
6907 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
6911 convert_move (real_decl_rtl, decl_rtl, unsignedp);
6913 else if (GET_CODE (real_decl_rtl) == PARALLEL)
6914 emit_group_load (real_decl_rtl, decl_rtl,
6915 int_size_in_bytes (TREE_TYPE (decl_result)),
6916 TYPE_ALIGN (TREE_TYPE (decl_result)));
6918 emit_move_insn (real_decl_rtl, decl_rtl);
6920 /* The delay slot scheduler assumes that current_function_return_rtx
6921 holds the hard register containing the return value, not a
6922 temporary pseudo. */
6923 current_function_return_rtx = real_decl_rtl;
6927 /* If returning a structure, arrange to return the address of the value
6928 in a place where debuggers expect to find it.
6930 If returning a structure PCC style,
6931 the caller also depends on this value.
6932 And current_function_returns_pcc_struct is not necessarily set. */
6933 if (current_function_returns_struct
6934 || current_function_returns_pcc_struct)
6937 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
6938 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
6939 #ifdef FUNCTION_OUTGOING_VALUE
6941 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
6942 current_function_decl);
6945 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
6948 /* Mark this as a function return value so integrate will delete the
6949 assignment and USE below when inlining this function. */
6950 REG_FUNCTION_VALUE_P (outgoing) = 1;
6952 #ifdef POINTERS_EXTEND_UNSIGNED
6953 /* The address may be ptr_mode and OUTGOING may be Pmode. */
6954 if (GET_MODE (outgoing) != GET_MODE (value_address))
6955 value_address = convert_memory_address (GET_MODE (outgoing),
6959 emit_move_insn (outgoing, value_address);
6961 /* Show return register used to hold result (in this case the address
6963 current_function_return_rtx = outgoing;
6966 /* If this is an implementation of throw, do what's necessary to
6967 communicate between __builtin_eh_return and the epilogue. */
6968 expand_eh_return ();
6970 /* Emit the actual code to clobber return register. */
6975 clobber_return_register ();
6976 seq = gen_sequence ();
6979 after = emit_insn_after (seq, clobber_after);
6981 if (clobber_after != after)
6982 cfun->x_clobber_return_insn = after;
6985 /* ??? This should no longer be necessary since stupid is no longer with
6986 us, but there are some parts of the compiler (eg reload_combine, and
6987 sh mach_dep_reorg) that still try and compute their own lifetime info
6988 instead of using the general framework. */
6989 use_return_register ();
6991 /* Output a return insn if we are using one.
6992 Otherwise, let the rtl chain end here, to drop through
6993 into the epilogue. */
6998 emit_jump_insn (gen_return ());
7003 /* Fix up any gotos that jumped out to the outermost
7004 binding level of the function.
7005 Must follow emitting RETURN_LABEL. */
7007 /* If you have any cleanups to do at this point,
7008 and they need to create temporary variables,
7009 then you will lose. */
7010 expand_fixups (get_insns ());
7013 /* Extend a vector that records the INSN_UIDs of INSNS (either a
7014 sequence or a single insn). */
7017 record_insns (insns, vecp)
7021 if (GET_CODE (insns) == SEQUENCE)
7023 int len = XVECLEN (insns, 0);
7024 int i = VARRAY_SIZE (*vecp);
7026 VARRAY_GROW (*vecp, i + len);
7029 VARRAY_INT (*vecp, i) = INSN_UID (XVECEXP (insns, 0, len));
7035 int i = VARRAY_SIZE (*vecp);
7036 VARRAY_GROW (*vecp, i + 1);
7037 VARRAY_INT (*vecp, i) = INSN_UID (insns);
7041 /* Determine how many INSN_UIDs in VEC are part of INSN. */
7044 contains (insn, vec)
7050 if (GET_CODE (insn) == INSN
7051 && GET_CODE (PATTERN (insn)) == SEQUENCE)
7054 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
7055 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7056 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
7062 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7063 if (INSN_UID (insn) == VARRAY_INT (vec, j))
7070 prologue_epilogue_contains (insn)
7073 if (contains (insn, prologue))
7075 if (contains (insn, epilogue))
7081 sibcall_epilogue_contains (insn)
7084 if (sibcall_epilogue)
7085 return contains (insn, sibcall_epilogue);
7090 /* Insert gen_return at the end of block BB. This also means updating
7091 block_for_insn appropriately. */
7094 emit_return_into_block (bb, line_note)
7100 p = NEXT_INSN (bb->end);
7101 end = emit_jump_insn_after (gen_return (), bb->end);
7103 emit_line_note_after (NOTE_SOURCE_FILE (line_note),
7104 NOTE_LINE_NUMBER (line_note), bb->end);
7108 set_block_for_insn (p, bb);
7115 #endif /* HAVE_return */
7117 #ifdef HAVE_epilogue
7119 /* Modify SEQ, a SEQUENCE that is part of the epilogue, to no modifications
7120 to the stack pointer. */
7123 keep_stack_depressed (seq)
7127 rtx sp_from_reg = 0;
7128 int sp_modified_unknown = 0;
7130 /* If the epilogue is just a single instruction, it's OK as is */
7132 if (GET_CODE (seq) != SEQUENCE)
7135 /* Scan all insns in SEQ looking for ones that modified the stack
7136 pointer. Record if it modified the stack pointer by copying it
7137 from the frame pointer or if it modified it in some other way.
7138 Then modify any subsequent stack pointer references to take that
7139 into account. We start by only allowing SP to be copied from a
7140 register (presumably FP) and then be subsequently referenced. */
7142 for (i = 0; i < XVECLEN (seq, 0); i++)
7144 rtx insn = XVECEXP (seq, 0, i);
7146 if (GET_RTX_CLASS (GET_CODE (insn)) != 'i')
7149 if (reg_set_p (stack_pointer_rtx, insn))
7151 rtx set = single_set (insn);
7153 /* If SP is set as a side-effect, we can't support this. */
7157 if (GET_CODE (SET_SRC (set)) == REG)
7158 sp_from_reg = SET_SRC (set);
7160 sp_modified_unknown = 1;
7162 /* Don't allow the SP modification to happen. */
7163 PUT_CODE (insn, NOTE);
7164 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
7165 NOTE_SOURCE_FILE (insn) = 0;
7167 else if (reg_referenced_p (stack_pointer_rtx, PATTERN (insn)))
7169 if (sp_modified_unknown)
7172 else if (sp_from_reg != 0)
7174 = replace_rtx (PATTERN (insn), stack_pointer_rtx, sp_from_reg);
7180 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7181 this into place with notes indicating where the prologue ends and where
7182 the epilogue begins. Update the basic block information when possible. */
7185 thread_prologue_and_epilogue_insns (f)
7186 rtx f ATTRIBUTE_UNUSED;
7191 #ifdef HAVE_prologue
7192 rtx prologue_end = NULL_RTX;
7194 #if defined (HAVE_epilogue) || defined(HAVE_return)
7195 rtx epilogue_end = NULL_RTX;
7198 #ifdef HAVE_prologue
7202 seq = gen_prologue ();
7205 /* Retain a map of the prologue insns. */
7206 if (GET_CODE (seq) != SEQUENCE)
7208 record_insns (seq, &prologue);
7209 prologue_end = emit_note (NULL, NOTE_INSN_PROLOGUE_END);
7211 seq = gen_sequence ();
7214 /* Can't deal with multiple successsors of the entry block
7215 at the moment. Function should always have at least one
7217 if (!ENTRY_BLOCK_PTR->succ || ENTRY_BLOCK_PTR->succ->succ_next)
7220 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
7225 /* If the exit block has no non-fake predecessors, we don't need
7227 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7228 if ((e->flags & EDGE_FAKE) == 0)
7234 if (optimize && HAVE_return)
7236 /* If we're allowed to generate a simple return instruction,
7237 then by definition we don't need a full epilogue. Examine
7238 the block that falls through to EXIT. If it does not
7239 contain any code, examine its predecessors and try to
7240 emit (conditional) return instructions. */
7246 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7247 if (e->flags & EDGE_FALLTHRU)
7253 /* Verify that there are no active instructions in the last block. */
7255 while (label && GET_CODE (label) != CODE_LABEL)
7257 if (active_insn_p (label))
7259 label = PREV_INSN (label);
7262 if (last->head == label && GET_CODE (label) == CODE_LABEL)
7264 rtx epilogue_line_note = NULL_RTX;
7266 /* Locate the line number associated with the closing brace,
7267 if we can find one. */
7268 for (seq = get_last_insn ();
7269 seq && ! active_insn_p (seq);
7270 seq = PREV_INSN (seq))
7271 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
7273 epilogue_line_note = seq;
7277 for (e = last->pred; e; e = e_next)
7279 basic_block bb = e->src;
7282 e_next = e->pred_next;
7283 if (bb == ENTRY_BLOCK_PTR)
7287 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
7290 /* If we have an unconditional jump, we can replace that
7291 with a simple return instruction. */
7292 if (simplejump_p (jump))
7294 emit_return_into_block (bb, epilogue_line_note);
7295 flow_delete_insn (jump);
7298 /* If we have a conditional jump, we can try to replace
7299 that with a conditional return instruction. */
7300 else if (condjump_p (jump))
7304 ret = SET_SRC (PATTERN (jump));
7305 if (GET_CODE (XEXP (ret, 1)) == LABEL_REF)
7306 loc = &XEXP (ret, 1);
7308 loc = &XEXP (ret, 2);
7309 ret = gen_rtx_RETURN (VOIDmode);
7311 if (! validate_change (jump, loc, ret, 0))
7313 if (JUMP_LABEL (jump))
7314 LABEL_NUSES (JUMP_LABEL (jump))--;
7316 /* If this block has only one successor, it both jumps
7317 and falls through to the fallthru block, so we can't
7319 if (bb->succ->succ_next == NULL)
7325 /* Fix up the CFG for the successful change we just made. */
7326 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7329 /* Emit a return insn for the exit fallthru block. Whether
7330 this is still reachable will be determined later. */
7332 emit_barrier_after (last->end);
7333 emit_return_into_block (last, epilogue_line_note);
7334 epilogue_end = last->end;
7339 #ifdef HAVE_epilogue
7342 /* Find the edge that falls through to EXIT. Other edges may exist
7343 due to RETURN instructions, but those don't need epilogues.
7344 There really shouldn't be a mixture -- either all should have
7345 been converted or none, however... */
7347 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7348 if (e->flags & EDGE_FALLTHRU)
7354 epilogue_end = emit_note (NULL, NOTE_INSN_EPILOGUE_BEG);
7356 seq = gen_epilogue ();
7358 /* If this function returns with the stack depressed, massage
7359 the epilogue to actually do that. */
7360 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7361 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7362 keep_stack_depressed (seq);
7364 emit_jump_insn (seq);
7366 /* Retain a map of the epilogue insns. */
7367 if (GET_CODE (seq) != SEQUENCE)
7369 record_insns (seq, &epilogue);
7371 seq = gen_sequence ();
7374 insert_insn_on_edge (seq, e);
7381 commit_edge_insertions ();
7383 #ifdef HAVE_sibcall_epilogue
7384 /* Emit sibling epilogues before any sibling call sites. */
7385 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7387 basic_block bb = e->src;
7392 if (GET_CODE (insn) != CALL_INSN
7393 || ! SIBLING_CALL_P (insn))
7397 seq = gen_sibcall_epilogue ();
7400 i = PREV_INSN (insn);
7401 newinsn = emit_insn_before (seq, insn);
7403 /* Update the UID to basic block map. */
7404 for (i = NEXT_INSN (i); i != insn; i = NEXT_INSN (i))
7405 set_block_for_insn (i, bb);
7407 /* Retain a map of the epilogue insns. Used in life analysis to
7408 avoid getting rid of sibcall epilogue insns. */
7409 record_insns (GET_CODE (seq) == SEQUENCE
7410 ? seq : newinsn, &sibcall_epilogue);
7414 #ifdef HAVE_prologue
7419 /* GDB handles `break f' by setting a breakpoint on the first
7420 line note after the prologue. Which means (1) that if
7421 there are line number notes before where we inserted the
7422 prologue we should move them, and (2) we should generate a
7423 note before the end of the first basic block, if there isn't
7426 ??? This behaviour is completely broken when dealing with
7427 multiple entry functions. We simply place the note always
7428 into first basic block and let alternate entry points
7432 for (insn = prologue_end; insn; insn = prev)
7434 prev = PREV_INSN (insn);
7435 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7437 /* Note that we cannot reorder the first insn in the
7438 chain, since rest_of_compilation relies on that
7439 remaining constant. */
7442 reorder_insns (insn, insn, prologue_end);
7446 /* Find the last line number note in the first block. */
7447 for (insn = BASIC_BLOCK (0)->end;
7448 insn != prologue_end && insn;
7449 insn = PREV_INSN (insn))
7450 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7453 /* If we didn't find one, make a copy of the first line number
7457 for (insn = next_active_insn (prologue_end);
7459 insn = PREV_INSN (insn))
7460 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7462 emit_line_note_after (NOTE_SOURCE_FILE (insn),
7463 NOTE_LINE_NUMBER (insn),
7470 #ifdef HAVE_epilogue
7475 /* Similarly, move any line notes that appear after the epilogue.
7476 There is no need, however, to be quite so anal about the existance
7478 for (insn = epilogue_end; insn; insn = next)
7480 next = NEXT_INSN (insn);
7481 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7482 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7488 /* Reposition the prologue-end and epilogue-begin notes after instruction
7489 scheduling and delayed branch scheduling. */
7492 reposition_prologue_and_epilogue_notes (f)
7493 rtx f ATTRIBUTE_UNUSED;
7495 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7498 if ((len = VARRAY_SIZE (prologue)) > 0)
7500 register rtx insn, note = 0;
7502 /* Scan from the beginning until we reach the last prologue insn.
7503 We apparently can't depend on basic_block_{head,end} after
7505 for (insn = f; len && insn; insn = NEXT_INSN (insn))
7507 if (GET_CODE (insn) == NOTE)
7509 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
7512 else if ((len -= contains (insn, prologue)) == 0)
7515 /* Find the prologue-end note if we haven't already, and
7516 move it to just after the last prologue insn. */
7519 for (note = insn; (note = NEXT_INSN (note));)
7520 if (GET_CODE (note) == NOTE
7521 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
7525 next = NEXT_INSN (note);
7527 /* Whether or not we can depend on BLOCK_HEAD,
7528 attempt to keep it up-to-date. */
7529 if (BLOCK_HEAD (0) == note)
7530 BLOCK_HEAD (0) = next;
7533 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
7534 if (GET_CODE (insn) == CODE_LABEL)
7535 insn = NEXT_INSN (insn);
7536 add_insn_after (note, insn);
7541 if ((len = VARRAY_SIZE (epilogue)) > 0)
7543 register rtx insn, note = 0;
7545 /* Scan from the end until we reach the first epilogue insn.
7546 We apparently can't depend on basic_block_{head,end} after
7548 for (insn = get_last_insn (); len && insn; insn = PREV_INSN (insn))
7550 if (GET_CODE (insn) == NOTE)
7552 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
7555 else if ((len -= contains (insn, epilogue)) == 0)
7557 /* Find the epilogue-begin note if we haven't already, and
7558 move it to just before the first epilogue insn. */
7561 for (note = insn; (note = PREV_INSN (note));)
7562 if (GET_CODE (note) == NOTE
7563 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
7567 /* Whether or not we can depend on BLOCK_HEAD,
7568 attempt to keep it up-to-date. */
7570 && BLOCK_HEAD (n_basic_blocks-1) == insn)
7571 BLOCK_HEAD (n_basic_blocks-1) = note;
7574 add_insn_before (note, insn);
7578 #endif /* HAVE_prologue or HAVE_epilogue */
7581 /* Mark T for GC. */
7585 struct temp_slot *t;
7589 ggc_mark_rtx (t->slot);
7590 ggc_mark_rtx (t->address);
7591 ggc_mark_tree (t->rtl_expr);
7592 ggc_mark_tree (t->type);
7598 /* Mark P for GC. */
7601 mark_function_status (p)
7610 ggc_mark_rtx (p->arg_offset_rtx);
7612 if (p->x_parm_reg_stack_loc)
7613 for (i = p->x_max_parm_reg, r = p->x_parm_reg_stack_loc;
7617 ggc_mark_rtx (p->return_rtx);
7618 ggc_mark_rtx (p->x_cleanup_label);
7619 ggc_mark_rtx (p->x_return_label);
7620 ggc_mark_rtx (p->x_save_expr_regs);
7621 ggc_mark_rtx (p->x_stack_slot_list);
7622 ggc_mark_rtx (p->x_parm_birth_insn);
7623 ggc_mark_rtx (p->x_tail_recursion_label);
7624 ggc_mark_rtx (p->x_tail_recursion_reentry);
7625 ggc_mark_rtx (p->internal_arg_pointer);
7626 ggc_mark_rtx (p->x_arg_pointer_save_area);
7627 ggc_mark_tree (p->x_rtl_expr_chain);
7628 ggc_mark_rtx (p->x_last_parm_insn);
7629 ggc_mark_tree (p->x_context_display);
7630 ggc_mark_tree (p->x_trampoline_list);
7631 ggc_mark_rtx (p->epilogue_delay_list);
7632 ggc_mark_rtx (p->x_clobber_return_insn);
7634 mark_temp_slot (p->x_temp_slots);
7637 struct var_refs_queue *q = p->fixup_var_refs_queue;
7640 ggc_mark_rtx (q->modified);
7645 ggc_mark_rtx (p->x_nonlocal_goto_handler_slots);
7646 ggc_mark_rtx (p->x_nonlocal_goto_handler_labels);
7647 ggc_mark_rtx (p->x_nonlocal_goto_stack_level);
7648 ggc_mark_tree (p->x_nonlocal_labels);
7650 mark_hard_reg_initial_vals (p);
7653 /* Mark the function chain ARG (which is really a struct function **)
7657 mark_function_chain (arg)
7660 struct function *f = *(struct function **) arg;
7662 for (; f; f = f->next_global)
7664 ggc_mark_tree (f->decl);
7666 mark_function_status (f);
7667 mark_eh_status (f->eh);
7668 mark_stmt_status (f->stmt);
7669 mark_expr_status (f->expr);
7670 mark_emit_status (f->emit);
7671 mark_varasm_status (f->varasm);
7673 if (mark_machine_status)
7674 (*mark_machine_status) (f);
7675 if (mark_lang_status)
7676 (*mark_lang_status) (f);
7678 if (f->original_arg_vector)
7679 ggc_mark_rtvec ((rtvec) f->original_arg_vector);
7680 if (f->original_decl_initial)
7681 ggc_mark_tree (f->original_decl_initial);
7685 /* Called once, at initialization, to initialize function.c. */
7688 init_function_once ()
7690 ggc_add_root (&all_functions, 1, sizeof all_functions,
7691 mark_function_chain);
7693 VARRAY_INT_INIT (prologue, 0, "prologue");
7694 VARRAY_INT_INIT (epilogue, 0, "epilogue");
7695 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");