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 #ifndef PREFERRED_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 /* Calculate this before we start messing with decl's RTL. */
2861 HOST_WIDE_INT set = get_alias_set (decl);
2863 /* If the original REG was a user-variable, then so is the REG whose
2864 address is being taken. Likewise for unchanging. */
2865 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2866 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2868 PUT_CODE (reg, MEM);
2872 tree type = TREE_TYPE (decl);
2873 enum machine_mode decl_mode
2874 = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
2875 : DECL_MODE (decl));
2877 PUT_MODE (reg, decl_mode);
2878 MEM_VOLATILE_P (reg) = TREE_SIDE_EFFECTS (decl);
2879 MEM_SET_IN_STRUCT_P (reg, AGGREGATE_TYPE_P (type));
2880 set_mem_alias_set (reg, set);
2882 if (TREE_USED (decl) || DECL_INITIAL (decl) != 0)
2883 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), 0);
2887 /* We have no alias information about this newly created MEM. */
2888 set_mem_alias_set (reg, 0);
2890 fixup_var_refs (reg, GET_MODE (reg), 0, 0);
2896 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2899 flush_addressof (decl)
2902 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2903 && DECL_RTL (decl) != 0
2904 && GET_CODE (DECL_RTL (decl)) == MEM
2905 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2906 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2907 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2910 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2913 put_addressof_into_stack (r, ht)
2915 struct hash_table *ht;
2918 int volatile_p, used_p;
2920 rtx reg = XEXP (r, 0);
2922 if (GET_CODE (reg) != REG)
2925 decl = ADDRESSOF_DECL (r);
2928 type = TREE_TYPE (decl);
2929 volatile_p = (TREE_CODE (decl) != SAVE_EXPR
2930 && TREE_THIS_VOLATILE (decl));
2931 used_p = (TREE_USED (decl)
2932 || (TREE_CODE (decl) != SAVE_EXPR
2933 && DECL_INITIAL (decl) != 0));
2942 put_reg_into_stack (0, reg, type, GET_MODE (reg), GET_MODE (reg),
2943 volatile_p, ADDRESSOF_REGNO (r), used_p, ht);
2946 /* List of replacements made below in purge_addressof_1 when creating
2947 bitfield insertions. */
2948 static rtx purge_bitfield_addressof_replacements;
2950 /* List of replacements made below in purge_addressof_1 for patterns
2951 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2952 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2953 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2954 enough in complex cases, e.g. when some field values can be
2955 extracted by usage MEM with narrower mode. */
2956 static rtx purge_addressof_replacements;
2958 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2959 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2960 the stack. If the function returns FALSE then the replacement could not
2964 purge_addressof_1 (loc, insn, force, store, ht)
2968 struct hash_table *ht;
2976 /* Re-start here to avoid recursion in common cases. */
2983 code = GET_CODE (x);
2985 /* If we don't return in any of the cases below, we will recurse inside
2986 the RTX, which will normally result in any ADDRESSOF being forced into
2990 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1, ht);
2991 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0, ht);
2994 else if (code == ADDRESSOF)
2998 if (GET_CODE (XEXP (x, 0)) != MEM)
3000 put_addressof_into_stack (x, ht);
3004 /* We must create a copy of the rtx because it was created by
3005 overwriting a REG rtx which is always shared. */
3006 sub = copy_rtx (XEXP (XEXP (x, 0), 0));
3007 if (validate_change (insn, loc, sub, 0)
3008 || validate_replace_rtx (x, sub, insn))
3012 sub = force_operand (sub, NULL_RTX);
3013 if (! validate_change (insn, loc, sub, 0)
3014 && ! validate_replace_rtx (x, sub, insn))
3017 insns = gen_sequence ();
3019 emit_insn_before (insns, insn);
3023 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
3025 rtx sub = XEXP (XEXP (x, 0), 0);
3027 if (GET_CODE (sub) == MEM)
3028 sub = adjust_address_nv (sub, GET_MODE (x), 0);
3029 else if (GET_CODE (sub) == REG
3030 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
3032 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
3034 int size_x, size_sub;
3038 /* When processing REG_NOTES look at the list of
3039 replacements done on the insn to find the register that X
3043 for (tem = purge_bitfield_addressof_replacements;
3045 tem = XEXP (XEXP (tem, 1), 1))
3046 if (rtx_equal_p (x, XEXP (tem, 0)))
3048 *loc = XEXP (XEXP (tem, 1), 0);
3052 /* See comment for purge_addressof_replacements. */
3053 for (tem = purge_addressof_replacements;
3055 tem = XEXP (XEXP (tem, 1), 1))
3056 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3058 rtx z = XEXP (XEXP (tem, 1), 0);
3060 if (GET_MODE (x) == GET_MODE (z)
3061 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
3062 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
3065 /* It can happen that the note may speak of things
3066 in a wider (or just different) mode than the
3067 code did. This is especially true of
3070 if (GET_CODE (z) == SUBREG && SUBREG_BYTE (z) == 0)
3073 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3074 && (GET_MODE_SIZE (GET_MODE (x))
3075 > GET_MODE_SIZE (GET_MODE (z))))
3077 /* This can occur as a result in invalid
3078 pointer casts, e.g. float f; ...
3079 *(long long int *)&f.
3080 ??? We could emit a warning here, but
3081 without a line number that wouldn't be
3083 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
3086 z = gen_lowpart (GET_MODE (x), z);
3092 /* Sometimes we may not be able to find the replacement. For
3093 example when the original insn was a MEM in a wider mode,
3094 and the note is part of a sign extension of a narrowed
3095 version of that MEM. Gcc testcase compile/990829-1.c can
3096 generate an example of this siutation. Rather than complain
3097 we return false, which will prompt our caller to remove the
3102 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3103 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3105 /* Don't even consider working with paradoxical subregs,
3106 or the moral equivalent seen here. */
3107 if (size_x <= size_sub
3108 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3110 /* Do a bitfield insertion to mirror what would happen
3117 rtx p = PREV_INSN (insn);
3120 val = gen_reg_rtx (GET_MODE (x));
3121 if (! validate_change (insn, loc, val, 0))
3123 /* Discard the current sequence and put the
3124 ADDRESSOF on stack. */
3128 seq = gen_sequence ();
3130 emit_insn_before (seq, insn);
3131 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3135 store_bit_field (sub, size_x, 0, GET_MODE (x),
3136 val, GET_MODE_SIZE (GET_MODE (sub)),
3137 GET_MODE_ALIGNMENT (GET_MODE (sub)));
3139 /* Make sure to unshare any shared rtl that store_bit_field
3140 might have created. */
3141 unshare_all_rtl_again (get_insns ());
3143 seq = gen_sequence ();
3145 p = emit_insn_after (seq, insn);
3146 if (NEXT_INSN (insn))
3147 compute_insns_for_mem (NEXT_INSN (insn),
3148 p ? NEXT_INSN (p) : NULL_RTX,
3153 rtx p = PREV_INSN (insn);
3156 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3157 GET_MODE (x), GET_MODE (x),
3158 GET_MODE_SIZE (GET_MODE (sub)),
3159 GET_MODE_SIZE (GET_MODE (sub)));
3161 if (! validate_change (insn, loc, val, 0))
3163 /* Discard the current sequence and put the
3164 ADDRESSOF on stack. */
3169 seq = gen_sequence ();
3171 emit_insn_before (seq, insn);
3172 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3176 /* Remember the replacement so that the same one can be done
3177 on the REG_NOTES. */
3178 purge_bitfield_addressof_replacements
3179 = gen_rtx_EXPR_LIST (VOIDmode, x,
3182 purge_bitfield_addressof_replacements));
3184 /* We replaced with a reg -- all done. */
3189 else if (validate_change (insn, loc, sub, 0))
3191 /* Remember the replacement so that the same one can be done
3192 on the REG_NOTES. */
3193 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3197 for (tem = purge_addressof_replacements;
3199 tem = XEXP (XEXP (tem, 1), 1))
3200 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3202 XEXP (XEXP (tem, 1), 0) = sub;
3205 purge_addressof_replacements
3206 = gen_rtx (EXPR_LIST, VOIDmode, XEXP (x, 0),
3207 gen_rtx_EXPR_LIST (VOIDmode, sub,
3208 purge_addressof_replacements));
3216 /* Scan all subexpressions. */
3217 fmt = GET_RTX_FORMAT (code);
3218 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3221 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0, ht);
3222 else if (*fmt == 'E')
3223 for (j = 0; j < XVECLEN (x, i); j++)
3224 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0, ht);
3230 /* Return a new hash table entry in HT. */
3232 static struct hash_entry *
3233 insns_for_mem_newfunc (he, ht, k)
3234 struct hash_entry *he;
3235 struct hash_table *ht;
3236 hash_table_key k ATTRIBUTE_UNUSED;
3238 struct insns_for_mem_entry *ifmhe;
3242 ifmhe = ((struct insns_for_mem_entry *)
3243 hash_allocate (ht, sizeof (struct insns_for_mem_entry)));
3244 ifmhe->insns = NULL_RTX;
3249 /* Return a hash value for K, a REG. */
3251 static unsigned long
3252 insns_for_mem_hash (k)
3255 /* K is really a RTX. Just use the address as the hash value. */
3256 return (unsigned long) k;
3259 /* Return non-zero if K1 and K2 (two REGs) are the same. */
3262 insns_for_mem_comp (k1, k2)
3269 struct insns_for_mem_walk_info {
3270 /* The hash table that we are using to record which INSNs use which
3272 struct hash_table *ht;
3274 /* The INSN we are currently proessing. */
3277 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3278 to find the insns that use the REGs in the ADDRESSOFs. */
3282 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3283 that might be used in an ADDRESSOF expression, record this INSN in
3284 the hash table given by DATA (which is really a pointer to an
3285 insns_for_mem_walk_info structure). */
3288 insns_for_mem_walk (r, data)
3292 struct insns_for_mem_walk_info *ifmwi
3293 = (struct insns_for_mem_walk_info *) data;
3295 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3296 && GET_CODE (XEXP (*r, 0)) == REG)
3297 hash_lookup (ifmwi->ht, XEXP (*r, 0), /*create=*/1, /*copy=*/0);
3298 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3300 /* Lookup this MEM in the hashtable, creating it if necessary. */
3301 struct insns_for_mem_entry *ifme
3302 = (struct insns_for_mem_entry *) hash_lookup (ifmwi->ht,
3307 /* If we have not already recorded this INSN, do so now. Since
3308 we process the INSNs in order, we know that if we have
3309 recorded it it must be at the front of the list. */
3310 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3311 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3318 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3319 which REGs in HT. */
3322 compute_insns_for_mem (insns, last_insn, ht)
3325 struct hash_table *ht;
3328 struct insns_for_mem_walk_info ifmwi;
3331 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3332 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3336 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3340 /* Helper function for purge_addressof called through for_each_rtx.
3341 Returns true iff the rtl is an ADDRESSOF. */
3344 is_addressof (rtl, data)
3346 void *data ATTRIBUTE_UNUSED;
3348 return GET_CODE (*rtl) == ADDRESSOF;
3351 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3352 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3356 purge_addressof (insns)
3360 struct hash_table ht;
3362 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3363 requires a fixup pass over the instruction stream to correct
3364 INSNs that depended on the REG being a REG, and not a MEM. But,
3365 these fixup passes are slow. Furthermore, most MEMs are not
3366 mentioned in very many instructions. So, we speed up the process
3367 by pre-calculating which REGs occur in which INSNs; that allows
3368 us to perform the fixup passes much more quickly. */
3369 hash_table_init (&ht,
3370 insns_for_mem_newfunc,
3372 insns_for_mem_comp);
3373 compute_insns_for_mem (insns, NULL_RTX, &ht);
3375 for (insn = insns; insn; insn = NEXT_INSN (insn))
3376 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3377 || GET_CODE (insn) == CALL_INSN)
3379 if (! purge_addressof_1 (&PATTERN (insn), insn,
3380 asm_noperands (PATTERN (insn)) > 0, 0, &ht))
3381 /* If we could not replace the ADDRESSOFs in the insn,
3382 something is wrong. */
3385 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, &ht))
3387 /* If we could not replace the ADDRESSOFs in the insn's notes,
3388 we can just remove the offending notes instead. */
3391 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3393 /* If we find a REG_RETVAL note then the insn is a libcall.
3394 Such insns must have REG_EQUAL notes as well, in order
3395 for later passes of the compiler to work. So it is not
3396 safe to delete the notes here, and instead we abort. */
3397 if (REG_NOTE_KIND (note) == REG_RETVAL)
3399 if (for_each_rtx (¬e, is_addressof, NULL))
3400 remove_note (insn, note);
3406 hash_table_free (&ht);
3407 purge_bitfield_addressof_replacements = 0;
3408 purge_addressof_replacements = 0;
3410 /* REGs are shared. purge_addressof will destructively replace a REG
3411 with a MEM, which creates shared MEMs.
3413 Unfortunately, the children of put_reg_into_stack assume that MEMs
3414 referring to the same stack slot are shared (fixup_var_refs and
3415 the associated hash table code).
3417 So, we have to do another unsharing pass after we have flushed any
3418 REGs that had their address taken into the stack.
3420 It may be worth tracking whether or not we converted any REGs into
3421 MEMs to avoid this overhead when it is not needed. */
3422 unshare_all_rtl_again (get_insns ());
3425 /* Convert a SET of a hard subreg to a set of the appropriet hard
3426 register. A subroutine of purge_hard_subreg_sets. */
3429 purge_single_hard_subreg_set (pattern)
3432 rtx reg = SET_DEST (pattern);
3433 enum machine_mode mode = GET_MODE (SET_DEST (pattern));
3436 if (GET_CODE (reg) == SUBREG && GET_CODE (SUBREG_REG (reg)) == REG
3437 && REGNO (SUBREG_REG (reg)) < FIRST_PSEUDO_REGISTER)
3439 offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)),
3440 GET_MODE (SUBREG_REG (reg)),
3443 reg = SUBREG_REG (reg);
3447 if (GET_CODE (reg) == REG && REGNO (reg) < FIRST_PSEUDO_REGISTER)
3449 reg = gen_rtx_REG (mode, REGNO (reg) + offset);
3450 SET_DEST (pattern) = reg;
3454 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The
3455 only such SETs that we expect to see are those left in because
3456 integrate can't handle sets of parts of a return value register.
3458 We don't use alter_subreg because we only want to eliminate subregs
3459 of hard registers. */
3462 purge_hard_subreg_sets (insn)
3465 for (; insn; insn = NEXT_INSN (insn))
3469 rtx pattern = PATTERN (insn);
3470 switch (GET_CODE (pattern))
3473 if (GET_CODE (SET_DEST (pattern)) == SUBREG)
3474 purge_single_hard_subreg_set (pattern);
3479 for (j = XVECLEN (pattern, 0) - 1; j >= 0; j--)
3481 rtx inner_pattern = XVECEXP (pattern, 0, j);
3482 if (GET_CODE (inner_pattern) == SET
3483 && GET_CODE (SET_DEST (inner_pattern)) == SUBREG)
3484 purge_single_hard_subreg_set (inner_pattern);
3495 /* Pass through the INSNS of function FNDECL and convert virtual register
3496 references to hard register references. */
3499 instantiate_virtual_regs (fndecl, insns)
3506 /* Compute the offsets to use for this function. */
3507 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3508 var_offset = STARTING_FRAME_OFFSET;
3509 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3510 out_arg_offset = STACK_POINTER_OFFSET;
3511 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl);
3513 /* Scan all variables and parameters of this function. For each that is
3514 in memory, instantiate all virtual registers if the result is a valid
3515 address. If not, we do it later. That will handle most uses of virtual
3516 regs on many machines. */
3517 instantiate_decls (fndecl, 1);
3519 /* Initialize recognition, indicating that volatile is OK. */
3522 /* Scan through all the insns, instantiating every virtual register still
3524 for (insn = insns; insn; insn = NEXT_INSN (insn))
3525 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3526 || GET_CODE (insn) == CALL_INSN)
3528 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3529 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3530 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
3531 if (GET_CODE (insn) == CALL_INSN)
3532 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn),
3536 /* Instantiate the stack slots for the parm registers, for later use in
3537 addressof elimination. */
3538 for (i = 0; i < max_parm_reg; ++i)
3539 if (parm_reg_stack_loc[i])
3540 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3542 /* Now instantiate the remaining register equivalences for debugging info.
3543 These will not be valid addresses. */
3544 instantiate_decls (fndecl, 0);
3546 /* Indicate that, from now on, assign_stack_local should use
3547 frame_pointer_rtx. */
3548 virtuals_instantiated = 1;
3551 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3552 all virtual registers in their DECL_RTL's.
3554 If VALID_ONLY, do this only if the resulting address is still valid.
3555 Otherwise, always do it. */
3558 instantiate_decls (fndecl, valid_only)
3564 /* Process all parameters of the function. */
3565 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3567 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3568 HOST_WIDE_INT size_rtl;
3570 instantiate_decl (DECL_RTL (decl), size, valid_only);
3572 /* If the parameter was promoted, then the incoming RTL mode may be
3573 larger than the declared type size. We must use the larger of
3575 size_rtl = GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl)));
3576 size = MAX (size_rtl, size);
3577 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3580 /* Now process all variables defined in the function or its subblocks. */
3581 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3584 /* Subroutine of instantiate_decls: Process all decls in the given
3585 BLOCK node and all its subblocks. */
3588 instantiate_decls_1 (let, valid_only)
3594 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3595 if (DECL_RTL_SET_P (t))
3596 instantiate_decl (DECL_RTL (t),
3597 int_size_in_bytes (TREE_TYPE (t)),
3600 /* Process all subblocks. */
3601 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3602 instantiate_decls_1 (t, valid_only);
3605 /* Subroutine of the preceding procedures: Given RTL representing a
3606 decl and the size of the object, do any instantiation required.
3608 If VALID_ONLY is non-zero, it means that the RTL should only be
3609 changed if the new address is valid. */
3612 instantiate_decl (x, size, valid_only)
3617 enum machine_mode mode;
3620 /* If this is not a MEM, no need to do anything. Similarly if the
3621 address is a constant or a register that is not a virtual register. */
3623 if (x == 0 || GET_CODE (x) != MEM)
3627 if (CONSTANT_P (addr)
3628 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3629 || (GET_CODE (addr) == REG
3630 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3631 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3634 /* If we should only do this if the address is valid, copy the address.
3635 We need to do this so we can undo any changes that might make the
3636 address invalid. This copy is unfortunate, but probably can't be
3640 addr = copy_rtx (addr);
3642 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3644 if (valid_only && size >= 0)
3646 unsigned HOST_WIDE_INT decl_size = size;
3648 /* Now verify that the resulting address is valid for every integer or
3649 floating-point mode up to and including SIZE bytes long. We do this
3650 since the object might be accessed in any mode and frame addresses
3653 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3654 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3655 mode = GET_MODE_WIDER_MODE (mode))
3656 if (! memory_address_p (mode, addr))
3659 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3660 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3661 mode = GET_MODE_WIDER_MODE (mode))
3662 if (! memory_address_p (mode, addr))
3666 /* Put back the address now that we have updated it and we either know
3667 it is valid or we don't care whether it is valid. */
3672 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
3673 is a virtual register, return the requivalent hard register and set the
3674 offset indirectly through the pointer. Otherwise, return 0. */
3677 instantiate_new_reg (x, poffset)
3679 HOST_WIDE_INT *poffset;
3682 HOST_WIDE_INT offset;
3684 if (x == virtual_incoming_args_rtx)
3685 new = arg_pointer_rtx, offset = in_arg_offset;
3686 else if (x == virtual_stack_vars_rtx)
3687 new = frame_pointer_rtx, offset = var_offset;
3688 else if (x == virtual_stack_dynamic_rtx)
3689 new = stack_pointer_rtx, offset = dynamic_offset;
3690 else if (x == virtual_outgoing_args_rtx)
3691 new = stack_pointer_rtx, offset = out_arg_offset;
3692 else if (x == virtual_cfa_rtx)
3693 new = arg_pointer_rtx, offset = cfa_offset;
3701 /* Given a pointer to a piece of rtx and an optional pointer to the
3702 containing object, instantiate any virtual registers present in it.
3704 If EXTRA_INSNS, we always do the replacement and generate
3705 any extra insns before OBJECT. If it zero, we do nothing if replacement
3708 Return 1 if we either had nothing to do or if we were able to do the
3709 needed replacement. Return 0 otherwise; we only return zero if
3710 EXTRA_INSNS is zero.
3712 We first try some simple transformations to avoid the creation of extra
3716 instantiate_virtual_regs_1 (loc, object, extra_insns)
3724 HOST_WIDE_INT offset = 0;
3730 /* Re-start here to avoid recursion in common cases. */
3737 code = GET_CODE (x);
3739 /* Check for some special cases. */
3756 /* We are allowed to set the virtual registers. This means that
3757 the actual register should receive the source minus the
3758 appropriate offset. This is used, for example, in the handling
3759 of non-local gotos. */
3760 if ((new = instantiate_new_reg (SET_DEST (x), &offset)) != 0)
3762 rtx src = SET_SRC (x);
3764 /* We are setting the register, not using it, so the relevant
3765 offset is the negative of the offset to use were we using
3768 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3770 /* The only valid sources here are PLUS or REG. Just do
3771 the simplest possible thing to handle them. */
3772 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3776 if (GET_CODE (src) != REG)
3777 temp = force_operand (src, NULL_RTX);
3780 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3784 emit_insns_before (seq, object);
3787 if (! validate_change (object, &SET_SRC (x), temp, 0)
3794 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3799 /* Handle special case of virtual register plus constant. */
3800 if (CONSTANT_P (XEXP (x, 1)))
3802 rtx old, new_offset;
3804 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3805 if (GET_CODE (XEXP (x, 0)) == PLUS)
3807 if ((new = instantiate_new_reg (XEXP (XEXP (x, 0), 0), &offset)))
3809 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3811 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3820 #ifdef POINTERS_EXTEND_UNSIGNED
3821 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
3822 we can commute the PLUS and SUBREG because pointers into the
3823 frame are well-behaved. */
3824 else if (GET_CODE (XEXP (x, 0)) == SUBREG && GET_MODE (x) == ptr_mode
3825 && GET_CODE (XEXP (x, 1)) == CONST_INT
3827 = instantiate_new_reg (SUBREG_REG (XEXP (x, 0)),
3829 && validate_change (object, loc,
3830 plus_constant (gen_lowpart (ptr_mode,
3833 + INTVAL (XEXP (x, 1))),
3837 else if ((new = instantiate_new_reg (XEXP (x, 0), &offset)) == 0)
3839 /* We know the second operand is a constant. Unless the
3840 first operand is a REG (which has been already checked),
3841 it needs to be checked. */
3842 if (GET_CODE (XEXP (x, 0)) != REG)
3850 new_offset = plus_constant (XEXP (x, 1), offset);
3852 /* If the new constant is zero, try to replace the sum with just
3854 if (new_offset == const0_rtx
3855 && validate_change (object, loc, new, 0))
3858 /* Next try to replace the register and new offset.
3859 There are two changes to validate here and we can't assume that
3860 in the case of old offset equals new just changing the register
3861 will yield a valid insn. In the interests of a little efficiency,
3862 however, we only call validate change once (we don't queue up the
3863 changes and then call apply_change_group). */
3867 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3868 : (XEXP (x, 0) = new,
3869 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3877 /* Otherwise copy the new constant into a register and replace
3878 constant with that register. */
3879 temp = gen_reg_rtx (Pmode);
3881 if (validate_change (object, &XEXP (x, 1), temp, 0))
3882 emit_insn_before (gen_move_insn (temp, new_offset), object);
3885 /* If that didn't work, replace this expression with a
3886 register containing the sum. */
3889 new = gen_rtx_PLUS (Pmode, new, new_offset);
3892 temp = force_operand (new, NULL_RTX);
3896 emit_insns_before (seq, object);
3897 if (! validate_change (object, loc, temp, 0)
3898 && ! validate_replace_rtx (x, temp, object))
3906 /* Fall through to generic two-operand expression case. */
3912 case DIV: case UDIV:
3913 case MOD: case UMOD:
3914 case AND: case IOR: case XOR:
3915 case ROTATERT: case ROTATE:
3916 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3918 case GE: case GT: case GEU: case GTU:
3919 case LE: case LT: case LEU: case LTU:
3920 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3921 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3926 /* Most cases of MEM that convert to valid addresses have already been
3927 handled by our scan of decls. The only special handling we
3928 need here is to make a copy of the rtx to ensure it isn't being
3929 shared if we have to change it to a pseudo.
3931 If the rtx is a simple reference to an address via a virtual register,
3932 it can potentially be shared. In such cases, first try to make it
3933 a valid address, which can also be shared. Otherwise, copy it and
3936 First check for common cases that need no processing. These are
3937 usually due to instantiation already being done on a previous instance
3941 if (CONSTANT_ADDRESS_P (temp)
3942 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3943 || temp == arg_pointer_rtx
3945 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3946 || temp == hard_frame_pointer_rtx
3948 || temp == frame_pointer_rtx)
3951 if (GET_CODE (temp) == PLUS
3952 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3953 && (XEXP (temp, 0) == frame_pointer_rtx
3954 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3955 || XEXP (temp, 0) == hard_frame_pointer_rtx
3957 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3958 || XEXP (temp, 0) == arg_pointer_rtx
3963 if (temp == virtual_stack_vars_rtx
3964 || temp == virtual_incoming_args_rtx
3965 || (GET_CODE (temp) == PLUS
3966 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3967 && (XEXP (temp, 0) == virtual_stack_vars_rtx
3968 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
3970 /* This MEM may be shared. If the substitution can be done without
3971 the need to generate new pseudos, we want to do it in place
3972 so all copies of the shared rtx benefit. The call below will
3973 only make substitutions if the resulting address is still
3976 Note that we cannot pass X as the object in the recursive call
3977 since the insn being processed may not allow all valid
3978 addresses. However, if we were not passed on object, we can
3979 only modify X without copying it if X will have a valid
3982 ??? Also note that this can still lose if OBJECT is an insn that
3983 has less restrictions on an address that some other insn.
3984 In that case, we will modify the shared address. This case
3985 doesn't seem very likely, though. One case where this could
3986 happen is in the case of a USE or CLOBBER reference, but we
3987 take care of that below. */
3989 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
3990 object ? object : x, 0))
3993 /* Otherwise make a copy and process that copy. We copy the entire
3994 RTL expression since it might be a PLUS which could also be
3996 *loc = x = copy_rtx (x);
3999 /* Fall through to generic unary operation case. */
4001 case STRICT_LOW_PART:
4003 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
4004 case SIGN_EXTEND: case ZERO_EXTEND:
4005 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
4006 case FLOAT: case FIX:
4007 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
4011 /* These case either have just one operand or we know that we need not
4012 check the rest of the operands. */
4018 /* If the operand is a MEM, see if the change is a valid MEM. If not,
4019 go ahead and make the invalid one, but do it to a copy. For a REG,
4020 just make the recursive call, since there's no chance of a problem. */
4022 if ((GET_CODE (XEXP (x, 0)) == MEM
4023 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
4025 || (GET_CODE (XEXP (x, 0)) == REG
4026 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
4029 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
4034 /* Try to replace with a PLUS. If that doesn't work, compute the sum
4035 in front of this insn and substitute the temporary. */
4036 if ((new = instantiate_new_reg (x, &offset)) != 0)
4038 temp = plus_constant (new, offset);
4039 if (!validate_change (object, loc, temp, 0))
4045 temp = force_operand (temp, NULL_RTX);
4049 emit_insns_before (seq, object);
4050 if (! validate_change (object, loc, temp, 0)
4051 && ! validate_replace_rtx (x, temp, object))
4059 if (GET_CODE (XEXP (x, 0)) == REG)
4062 else if (GET_CODE (XEXP (x, 0)) == MEM)
4064 /* If we have a (addressof (mem ..)), do any instantiation inside
4065 since we know we'll be making the inside valid when we finally
4066 remove the ADDRESSOF. */
4067 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
4076 /* Scan all subexpressions. */
4077 fmt = GET_RTX_FORMAT (code);
4078 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
4081 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
4084 else if (*fmt == 'E')
4085 for (j = 0; j < XVECLEN (x, i); j++)
4086 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
4093 /* Optimization: assuming this function does not receive nonlocal gotos,
4094 delete the handlers for such, as well as the insns to establish
4095 and disestablish them. */
4101 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4103 /* Delete the handler by turning off the flag that would
4104 prevent jump_optimize from deleting it.
4105 Also permit deletion of the nonlocal labels themselves
4106 if nothing local refers to them. */
4107 if (GET_CODE (insn) == CODE_LABEL)
4111 LABEL_PRESERVE_P (insn) = 0;
4113 /* Remove it from the nonlocal_label list, to avoid confusing
4115 for (t = nonlocal_labels, last_t = 0; t;
4116 last_t = t, t = TREE_CHAIN (t))
4117 if (DECL_RTL (TREE_VALUE (t)) == insn)
4122 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
4124 TREE_CHAIN (last_t) = TREE_CHAIN (t);
4127 if (GET_CODE (insn) == INSN)
4131 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
4132 if (reg_mentioned_p (t, PATTERN (insn)))
4138 || (nonlocal_goto_stack_level != 0
4139 && reg_mentioned_p (nonlocal_goto_stack_level,
4149 return max_parm_reg;
4152 /* Return the first insn following those generated by `assign_parms'. */
4155 get_first_nonparm_insn ()
4158 return NEXT_INSN (last_parm_insn);
4159 return get_insns ();
4162 /* Return the first NOTE_INSN_BLOCK_BEG note in the function.
4163 Crash if there is none. */
4166 get_first_block_beg ()
4168 register rtx searcher;
4169 register rtx insn = get_first_nonparm_insn ();
4171 for (searcher = insn; searcher; searcher = NEXT_INSN (searcher))
4172 if (GET_CODE (searcher) == NOTE
4173 && NOTE_LINE_NUMBER (searcher) == NOTE_INSN_BLOCK_BEG)
4176 abort (); /* Invalid call to this function. (See comments above.) */
4180 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4181 This means a type for which function calls must pass an address to the
4182 function or get an address back from the function.
4183 EXP may be a type node or an expression (whose type is tested). */
4186 aggregate_value_p (exp)
4189 int i, regno, nregs;
4192 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4194 if (TREE_CODE (type) == VOID_TYPE)
4196 if (RETURN_IN_MEMORY (type))
4198 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4199 and thus can't be returned in registers. */
4200 if (TREE_ADDRESSABLE (type))
4202 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4204 /* Make sure we have suitable call-clobbered regs to return
4205 the value in; if not, we must return it in memory. */
4206 reg = hard_function_value (type, 0, 0);
4208 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4210 if (GET_CODE (reg) != REG)
4213 regno = REGNO (reg);
4214 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
4215 for (i = 0; i < nregs; i++)
4216 if (! call_used_regs[regno + i])
4221 /* Assign RTL expressions to the function's parameters.
4222 This may involve copying them into registers and using
4223 those registers as the RTL for them. */
4226 assign_parms (fndecl)
4230 register rtx entry_parm = 0;
4231 register rtx stack_parm = 0;
4232 CUMULATIVE_ARGS args_so_far;
4233 enum machine_mode promoted_mode, passed_mode;
4234 enum machine_mode nominal_mode, promoted_nominal_mode;
4236 /* Total space needed so far for args on the stack,
4237 given as a constant and a tree-expression. */
4238 struct args_size stack_args_size;
4239 tree fntype = TREE_TYPE (fndecl);
4240 tree fnargs = DECL_ARGUMENTS (fndecl);
4241 /* This is used for the arg pointer when referring to stack args. */
4242 rtx internal_arg_pointer;
4243 /* This is a dummy PARM_DECL that we used for the function result if
4244 the function returns a structure. */
4245 tree function_result_decl = 0;
4246 #ifdef SETUP_INCOMING_VARARGS
4247 int varargs_setup = 0;
4249 rtx conversion_insns = 0;
4250 struct args_size alignment_pad;
4252 /* Nonzero if the last arg is named `__builtin_va_alist',
4253 which is used on some machines for old-fashioned non-ANSI varargs.h;
4254 this should be stuck onto the stack as if it had arrived there. */
4256 = (current_function_varargs
4258 && (parm = tree_last (fnargs)) != 0
4260 && (! strcmp (IDENTIFIER_POINTER (DECL_NAME (parm)),
4261 "__builtin_va_alist")));
4263 /* Nonzero if function takes extra anonymous args.
4264 This means the last named arg must be on the stack
4265 right before the anonymous ones. */
4267 = (TYPE_ARG_TYPES (fntype) != 0
4268 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4269 != void_type_node));
4271 current_function_stdarg = stdarg;
4273 /* If the reg that the virtual arg pointer will be translated into is
4274 not a fixed reg or is the stack pointer, make a copy of the virtual
4275 arg pointer, and address parms via the copy. The frame pointer is
4276 considered fixed even though it is not marked as such.
4278 The second time through, simply use ap to avoid generating rtx. */
4280 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4281 || ! (fixed_regs[ARG_POINTER_REGNUM]
4282 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4283 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4285 internal_arg_pointer = virtual_incoming_args_rtx;
4286 current_function_internal_arg_pointer = internal_arg_pointer;
4288 stack_args_size.constant = 0;
4289 stack_args_size.var = 0;
4291 /* If struct value address is treated as the first argument, make it so. */
4292 if (aggregate_value_p (DECL_RESULT (fndecl))
4293 && ! current_function_returns_pcc_struct
4294 && struct_value_incoming_rtx == 0)
4296 tree type = build_pointer_type (TREE_TYPE (fntype));
4298 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4300 DECL_ARG_TYPE (function_result_decl) = type;
4301 TREE_CHAIN (function_result_decl) = fnargs;
4302 fnargs = function_result_decl;
4305 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4306 parm_reg_stack_loc = (rtx *) xcalloc (max_parm_reg, sizeof (rtx));
4308 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4309 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4311 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, 0);
4314 /* We haven't yet found an argument that we must push and pretend the
4316 current_function_pretend_args_size = 0;
4318 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4320 struct args_size stack_offset;
4321 struct args_size arg_size;
4322 int passed_pointer = 0;
4323 int did_conversion = 0;
4324 tree passed_type = DECL_ARG_TYPE (parm);
4325 tree nominal_type = TREE_TYPE (parm);
4328 /* Set LAST_NAMED if this is last named arg before some
4330 int last_named = ((TREE_CHAIN (parm) == 0
4331 || DECL_NAME (TREE_CHAIN (parm)) == 0)
4332 && (stdarg || current_function_varargs));
4333 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4334 most machines, if this is a varargs/stdarg function, then we treat
4335 the last named arg as if it were anonymous too. */
4336 int named_arg = STRICT_ARGUMENT_NAMING ? 1 : ! last_named;
4338 if (TREE_TYPE (parm) == error_mark_node
4339 /* This can happen after weird syntax errors
4340 or if an enum type is defined among the parms. */
4341 || TREE_CODE (parm) != PARM_DECL
4342 || passed_type == NULL)
4344 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx));
4345 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4346 TREE_USED (parm) = 1;
4350 /* For varargs.h function, save info about regs and stack space
4351 used by the individual args, not including the va_alist arg. */
4352 if (hide_last_arg && last_named)
4353 current_function_args_info = args_so_far;
4355 /* Find mode of arg as it is passed, and mode of arg
4356 as it should be during execution of this function. */
4357 passed_mode = TYPE_MODE (passed_type);
4358 nominal_mode = TYPE_MODE (nominal_type);
4360 /* If the parm's mode is VOID, its value doesn't matter,
4361 and avoid the usual things like emit_move_insn that could crash. */
4362 if (nominal_mode == VOIDmode)
4364 SET_DECL_RTL (parm, const0_rtx);
4365 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4369 /* If the parm is to be passed as a transparent union, use the
4370 type of the first field for the tests below. We have already
4371 verified that the modes are the same. */
4372 if (DECL_TRANSPARENT_UNION (parm)
4373 || (TREE_CODE (passed_type) == UNION_TYPE
4374 && TYPE_TRANSPARENT_UNION (passed_type)))
4375 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4377 /* See if this arg was passed by invisible reference. It is if
4378 it is an object whose size depends on the contents of the
4379 object itself or if the machine requires these objects be passed
4382 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
4383 && contains_placeholder_p (TYPE_SIZE (passed_type)))
4384 || TREE_ADDRESSABLE (passed_type)
4385 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4386 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4387 passed_type, named_arg)
4391 passed_type = nominal_type = build_pointer_type (passed_type);
4393 passed_mode = nominal_mode = Pmode;
4396 promoted_mode = passed_mode;
4398 #ifdef PROMOTE_FUNCTION_ARGS
4399 /* Compute the mode in which the arg is actually extended to. */
4400 unsignedp = TREE_UNSIGNED (passed_type);
4401 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4404 /* Let machine desc say which reg (if any) the parm arrives in.
4405 0 means it arrives on the stack. */
4406 #ifdef FUNCTION_INCOMING_ARG
4407 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4408 passed_type, named_arg);
4410 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4411 passed_type, named_arg);
4414 if (entry_parm == 0)
4415 promoted_mode = passed_mode;
4417 #ifdef SETUP_INCOMING_VARARGS
4418 /* If this is the last named parameter, do any required setup for
4419 varargs or stdargs. We need to know about the case of this being an
4420 addressable type, in which case we skip the registers it
4421 would have arrived in.
4423 For stdargs, LAST_NAMED will be set for two parameters, the one that
4424 is actually the last named, and the dummy parameter. We only
4425 want to do this action once.
4427 Also, indicate when RTL generation is to be suppressed. */
4428 if (last_named && !varargs_setup)
4430 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
4431 current_function_pretend_args_size, 0);
4436 /* Determine parm's home in the stack,
4437 in case it arrives in the stack or we should pretend it did.
4439 Compute the stack position and rtx where the argument arrives
4442 There is one complexity here: If this was a parameter that would
4443 have been passed in registers, but wasn't only because it is
4444 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4445 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4446 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4447 0 as it was the previous time. */
4449 pretend_named = named_arg || PRETEND_OUTGOING_VARARGS_NAMED;
4450 locate_and_pad_parm (promoted_mode, passed_type,
4451 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4454 #ifdef FUNCTION_INCOMING_ARG
4455 FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4457 pretend_named) != 0,
4459 FUNCTION_ARG (args_so_far, promoted_mode,
4461 pretend_named) != 0,
4464 fndecl, &stack_args_size, &stack_offset, &arg_size,
4468 rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
4470 if (offset_rtx == const0_rtx)
4471 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4473 stack_parm = gen_rtx_MEM (promoted_mode,
4474 gen_rtx_PLUS (Pmode,
4475 internal_arg_pointer,
4478 set_mem_attributes (stack_parm, parm, 1);
4481 /* If this parameter was passed both in registers and in the stack,
4482 use the copy on the stack. */
4483 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4486 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4487 /* If this parm was passed part in regs and part in memory,
4488 pretend it arrived entirely in memory
4489 by pushing the register-part onto the stack.
4491 In the special case of a DImode or DFmode that is split,
4492 we could put it together in a pseudoreg directly,
4493 but for now that's not worth bothering with. */
4497 int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4498 passed_type, named_arg);
4502 current_function_pretend_args_size
4503 = (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
4504 / (PARM_BOUNDARY / BITS_PER_UNIT)
4505 * (PARM_BOUNDARY / BITS_PER_UNIT));
4507 /* Handle calls that pass values in multiple non-contiguous
4508 locations. The Irix 6 ABI has examples of this. */
4509 if (GET_CODE (entry_parm) == PARALLEL)
4510 emit_group_store (validize_mem (stack_parm), entry_parm,
4511 int_size_in_bytes (TREE_TYPE (parm)),
4512 TYPE_ALIGN (TREE_TYPE (parm)));
4515 move_block_from_reg (REGNO (entry_parm),
4516 validize_mem (stack_parm), nregs,
4517 int_size_in_bytes (TREE_TYPE (parm)));
4519 entry_parm = stack_parm;
4524 /* If we didn't decide this parm came in a register,
4525 by default it came on the stack. */
4526 if (entry_parm == 0)
4527 entry_parm = stack_parm;
4529 /* Record permanently how this parm was passed. */
4530 DECL_INCOMING_RTL (parm) = entry_parm;
4532 /* If there is actually space on the stack for this parm,
4533 count it in stack_args_size; otherwise set stack_parm to 0
4534 to indicate there is no preallocated stack slot for the parm. */
4536 if (entry_parm == stack_parm
4537 || (GET_CODE (entry_parm) == PARALLEL
4538 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4539 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4540 /* On some machines, even if a parm value arrives in a register
4541 there is still an (uninitialized) stack slot allocated for it.
4543 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4544 whether this parameter already has a stack slot allocated,
4545 because an arg block exists only if current_function_args_size
4546 is larger than some threshold, and we haven't calculated that
4547 yet. So, for now, we just assume that stack slots never exist
4549 || REG_PARM_STACK_SPACE (fndecl) > 0
4553 stack_args_size.constant += arg_size.constant;
4555 ADD_PARM_SIZE (stack_args_size, arg_size.var);
4558 /* No stack slot was pushed for this parm. */
4561 /* Update info on where next arg arrives in registers. */
4563 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4564 passed_type, named_arg);
4566 /* If we can't trust the parm stack slot to be aligned enough
4567 for its ultimate type, don't use that slot after entry.
4568 We'll make another stack slot, if we need one. */
4570 unsigned int thisparm_boundary
4571 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4573 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4577 /* If parm was passed in memory, and we need to convert it on entry,
4578 don't store it back in that same slot. */
4580 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4583 /* When an argument is passed in multiple locations, we can't
4584 make use of this information, but we can save some copying if
4585 the whole argument is passed in a single register. */
4586 if (GET_CODE (entry_parm) == PARALLEL
4587 && nominal_mode != BLKmode && passed_mode != BLKmode)
4589 int i, len = XVECLEN (entry_parm, 0);
4591 for (i = 0; i < len; i++)
4592 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
4593 && GET_CODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) == REG
4594 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
4596 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
4598 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
4599 DECL_INCOMING_RTL (parm) = entry_parm;
4604 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4605 in the mode in which it arrives.
4606 STACK_PARM is an RTX for a stack slot where the parameter can live
4607 during the function (in case we want to put it there).
4608 STACK_PARM is 0 if no stack slot was pushed for it.
4610 Now output code if necessary to convert ENTRY_PARM to
4611 the type in which this function declares it,
4612 and store that result in an appropriate place,
4613 which may be a pseudo reg, may be STACK_PARM,
4614 or may be a local stack slot if STACK_PARM is 0.
4616 Set DECL_RTL to that place. */
4618 if (nominal_mode == BLKmode || GET_CODE (entry_parm) == PARALLEL)
4620 /* If a BLKmode arrives in registers, copy it to a stack slot.
4621 Handle calls that pass values in multiple non-contiguous
4622 locations. The Irix 6 ABI has examples of this. */
4623 if (GET_CODE (entry_parm) == REG
4624 || GET_CODE (entry_parm) == PARALLEL)
4627 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
4630 /* Note that we will be storing an integral number of words.
4631 So we have to be careful to ensure that we allocate an
4632 integral number of words. We do this below in the
4633 assign_stack_local if space was not allocated in the argument
4634 list. If it was, this will not work if PARM_BOUNDARY is not
4635 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4636 if it becomes a problem. */
4638 if (stack_parm == 0)
4641 = assign_stack_local (GET_MODE (entry_parm),
4643 set_mem_attributes (stack_parm, parm, 1);
4646 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4649 /* Handle calls that pass values in multiple non-contiguous
4650 locations. The Irix 6 ABI has examples of this. */
4651 if (GET_CODE (entry_parm) == PARALLEL)
4652 emit_group_store (validize_mem (stack_parm), entry_parm,
4653 int_size_in_bytes (TREE_TYPE (parm)),
4654 TYPE_ALIGN (TREE_TYPE (parm)));
4656 move_block_from_reg (REGNO (entry_parm),
4657 validize_mem (stack_parm),
4658 size_stored / UNITS_PER_WORD,
4659 int_size_in_bytes (TREE_TYPE (parm)));
4661 SET_DECL_RTL (parm, stack_parm);
4663 else if (! ((! optimize
4664 && ! DECL_REGISTER (parm)
4665 && ! DECL_INLINE (fndecl))
4666 || TREE_SIDE_EFFECTS (parm)
4667 /* If -ffloat-store specified, don't put explicit
4668 float variables into registers. */
4669 || (flag_float_store
4670 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4671 /* Always assign pseudo to structure return or item passed
4672 by invisible reference. */
4673 || passed_pointer || parm == function_result_decl)
4675 /* Store the parm in a pseudoregister during the function, but we
4676 may need to do it in a wider mode. */
4678 register rtx parmreg;
4679 unsigned int regno, regnoi = 0, regnor = 0;
4681 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4683 promoted_nominal_mode
4684 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4686 parmreg = gen_reg_rtx (promoted_nominal_mode);
4687 mark_user_reg (parmreg);
4689 /* If this was an item that we received a pointer to, set DECL_RTL
4694 gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)),
4696 set_mem_attributes (DECL_RTL (parm), parm, 1);
4700 SET_DECL_RTL (parm, parmreg);
4701 maybe_set_unchanging (DECL_RTL (parm), parm);
4704 /* Copy the value into the register. */
4705 if (nominal_mode != passed_mode
4706 || promoted_nominal_mode != promoted_mode)
4709 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4710 mode, by the caller. We now have to convert it to
4711 NOMINAL_MODE, if different. However, PARMREG may be in
4712 a different mode than NOMINAL_MODE if it is being stored
4715 If ENTRY_PARM is a hard register, it might be in a register
4716 not valid for operating in its mode (e.g., an odd-numbered
4717 register for a DFmode). In that case, moves are the only
4718 thing valid, so we can't do a convert from there. This
4719 occurs when the calling sequence allow such misaligned
4722 In addition, the conversion may involve a call, which could
4723 clobber parameters which haven't been copied to pseudo
4724 registers yet. Therefore, we must first copy the parm to
4725 a pseudo reg here, and save the conversion until after all
4726 parameters have been moved. */
4728 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4730 emit_move_insn (tempreg, validize_mem (entry_parm));
4732 push_to_sequence (conversion_insns);
4733 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4735 if (GET_CODE (tempreg) == SUBREG
4736 && GET_MODE (tempreg) == nominal_mode
4737 && GET_CODE (SUBREG_REG (tempreg)) == REG
4738 && nominal_mode == passed_mode
4739 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm)
4740 && GET_MODE_SIZE (GET_MODE (tempreg))
4741 < GET_MODE_SIZE (GET_MODE (entry_parm)))
4743 /* The argument is already sign/zero extended, so note it
4745 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
4746 SUBREG_PROMOTED_UNSIGNED_P (tempreg) = unsignedp;
4749 /* TREE_USED gets set erroneously during expand_assignment. */
4750 save_tree_used = TREE_USED (parm);
4751 expand_assignment (parm,
4752 make_tree (nominal_type, tempreg), 0, 0);
4753 TREE_USED (parm) = save_tree_used;
4754 conversion_insns = get_insns ();
4759 emit_move_insn (parmreg, validize_mem (entry_parm));
4761 /* If we were passed a pointer but the actual value
4762 can safely live in a register, put it in one. */
4763 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4765 && ! DECL_REGISTER (parm)
4766 && ! DECL_INLINE (fndecl))
4767 || TREE_SIDE_EFFECTS (parm)
4768 /* If -ffloat-store specified, don't put explicit
4769 float variables into registers. */
4770 || (flag_float_store
4771 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE)))
4773 /* We can't use nominal_mode, because it will have been set to
4774 Pmode above. We must use the actual mode of the parm. */
4775 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4776 mark_user_reg (parmreg);
4777 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
4779 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
4780 int unsigned_p = TREE_UNSIGNED (TREE_TYPE (parm));
4781 push_to_sequence (conversion_insns);
4782 emit_move_insn (tempreg, DECL_RTL (parm));
4784 convert_to_mode (GET_MODE (parmreg),
4787 emit_move_insn (parmreg, DECL_RTL (parm));
4788 conversion_insns = get_insns();
4793 emit_move_insn (parmreg, DECL_RTL (parm));
4794 SET_DECL_RTL (parm, parmreg);
4795 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4799 #ifdef FUNCTION_ARG_CALLEE_COPIES
4800 /* If we are passed an arg by reference and it is our responsibility
4801 to make a copy, do it now.
4802 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4803 original argument, so we must recreate them in the call to
4804 FUNCTION_ARG_CALLEE_COPIES. */
4805 /* ??? Later add code to handle the case that if the argument isn't
4806 modified, don't do the copy. */
4808 else if (passed_pointer
4809 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4810 TYPE_MODE (DECL_ARG_TYPE (parm)),
4811 DECL_ARG_TYPE (parm),
4813 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4816 tree type = DECL_ARG_TYPE (parm);
4818 /* This sequence may involve a library call perhaps clobbering
4819 registers that haven't been copied to pseudos yet. */
4821 push_to_sequence (conversion_insns);
4823 if (!COMPLETE_TYPE_P (type)
4824 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4825 /* This is a variable sized object. */
4826 copy = gen_rtx_MEM (BLKmode,
4827 allocate_dynamic_stack_space
4828 (expr_size (parm), NULL_RTX,
4829 TYPE_ALIGN (type)));
4831 copy = assign_stack_temp (TYPE_MODE (type),
4832 int_size_in_bytes (type), 1);
4833 set_mem_attributes (copy, parm, 1);
4835 store_expr (parm, copy, 0);
4836 emit_move_insn (parmreg, XEXP (copy, 0));
4837 if (current_function_check_memory_usage)
4838 emit_library_call (chkr_set_right_libfunc,
4839 LCT_CONST_MAKE_BLOCK, VOIDmode, 3,
4840 XEXP (copy, 0), Pmode,
4841 GEN_INT (int_size_in_bytes (type)),
4842 TYPE_MODE (sizetype),
4843 GEN_INT (MEMORY_USE_RW),
4844 TYPE_MODE (integer_type_node));
4845 conversion_insns = get_insns ();
4849 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4851 /* In any case, record the parm's desired stack location
4852 in case we later discover it must live in the stack.
4854 If it is a COMPLEX value, store the stack location for both
4857 if (GET_CODE (parmreg) == CONCAT)
4858 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4860 regno = REGNO (parmreg);
4862 if (regno >= max_parm_reg)
4865 int old_max_parm_reg = max_parm_reg;
4867 /* It's slow to expand this one register at a time,
4868 but it's also rare and we need max_parm_reg to be
4869 precisely correct. */
4870 max_parm_reg = regno + 1;
4871 new = (rtx *) xrealloc (parm_reg_stack_loc,
4872 max_parm_reg * sizeof (rtx));
4873 memset ((char *) (new + old_max_parm_reg), 0,
4874 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4875 parm_reg_stack_loc = new;
4878 if (GET_CODE (parmreg) == CONCAT)
4880 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
4882 regnor = REGNO (gen_realpart (submode, parmreg));
4883 regnoi = REGNO (gen_imagpart (submode, parmreg));
4885 if (stack_parm != 0)
4887 parm_reg_stack_loc[regnor]
4888 = gen_realpart (submode, stack_parm);
4889 parm_reg_stack_loc[regnoi]
4890 = gen_imagpart (submode, stack_parm);
4894 parm_reg_stack_loc[regnor] = 0;
4895 parm_reg_stack_loc[regnoi] = 0;
4899 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
4901 /* Mark the register as eliminable if we did no conversion
4902 and it was copied from memory at a fixed offset,
4903 and the arg pointer was not copied to a pseudo-reg.
4904 If the arg pointer is a pseudo reg or the offset formed
4905 an invalid address, such memory-equivalences
4906 as we make here would screw up life analysis for it. */
4907 if (nominal_mode == passed_mode
4910 && GET_CODE (stack_parm) == MEM
4911 && stack_offset.var == 0
4912 && reg_mentioned_p (virtual_incoming_args_rtx,
4913 XEXP (stack_parm, 0)))
4915 rtx linsn = get_last_insn ();
4918 /* Mark complex types separately. */
4919 if (GET_CODE (parmreg) == CONCAT)
4920 /* Scan backwards for the set of the real and
4922 for (sinsn = linsn; sinsn != 0;
4923 sinsn = prev_nonnote_insn (sinsn))
4925 set = single_set (sinsn);
4927 && SET_DEST (set) == regno_reg_rtx [regnoi])
4929 = gen_rtx_EXPR_LIST (REG_EQUIV,
4930 parm_reg_stack_loc[regnoi],
4933 && SET_DEST (set) == regno_reg_rtx [regnor])
4935 = gen_rtx_EXPR_LIST (REG_EQUIV,
4936 parm_reg_stack_loc[regnor],
4939 else if ((set = single_set (linsn)) != 0
4940 && SET_DEST (set) == parmreg)
4942 = gen_rtx_EXPR_LIST (REG_EQUIV,
4943 stack_parm, REG_NOTES (linsn));
4946 /* For pointer data type, suggest pointer register. */
4947 if (POINTER_TYPE_P (TREE_TYPE (parm)))
4948 mark_reg_pointer (parmreg,
4949 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
4951 /* If something wants our address, try to use ADDRESSOF. */
4952 if (TREE_ADDRESSABLE (parm))
4954 /* If we end up putting something into the stack,
4955 fixup_var_refs_insns will need to make a pass over
4956 all the instructions. It looks throughs the pending
4957 sequences -- but it can't see the ones in the
4958 CONVERSION_INSNS, if they're not on the sequence
4959 stack. So, we go back to that sequence, just so that
4960 the fixups will happen. */
4961 push_to_sequence (conversion_insns);
4962 put_var_into_stack (parm);
4963 conversion_insns = get_insns ();
4969 /* Value must be stored in the stack slot STACK_PARM
4970 during function execution. */
4972 if (promoted_mode != nominal_mode)
4974 /* Conversion is required. */
4975 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4977 emit_move_insn (tempreg, validize_mem (entry_parm));
4979 push_to_sequence (conversion_insns);
4980 entry_parm = convert_to_mode (nominal_mode, tempreg,
4981 TREE_UNSIGNED (TREE_TYPE (parm)));
4983 /* ??? This may need a big-endian conversion on sparc64. */
4984 stack_parm = adjust_address (stack_parm, nominal_mode, 0);
4986 conversion_insns = get_insns ();
4991 if (entry_parm != stack_parm)
4993 if (stack_parm == 0)
4996 = assign_stack_local (GET_MODE (entry_parm),
4997 GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
4998 set_mem_attributes (stack_parm, parm, 1);
5001 if (promoted_mode != nominal_mode)
5003 push_to_sequence (conversion_insns);
5004 emit_move_insn (validize_mem (stack_parm),
5005 validize_mem (entry_parm));
5006 conversion_insns = get_insns ();
5010 emit_move_insn (validize_mem (stack_parm),
5011 validize_mem (entry_parm));
5013 if (current_function_check_memory_usage)
5015 push_to_sequence (conversion_insns);
5016 emit_library_call (chkr_set_right_libfunc, LCT_CONST_MAKE_BLOCK,
5017 VOIDmode, 3, XEXP (stack_parm, 0), Pmode,
5018 GEN_INT (GET_MODE_SIZE (GET_MODE
5020 TYPE_MODE (sizetype),
5021 GEN_INT (MEMORY_USE_RW),
5022 TYPE_MODE (integer_type_node));
5024 conversion_insns = get_insns ();
5027 SET_DECL_RTL (parm, stack_parm);
5030 /* If this "parameter" was the place where we are receiving the
5031 function's incoming structure pointer, set up the result. */
5032 if (parm == function_result_decl)
5034 tree result = DECL_RESULT (fndecl);
5036 SET_DECL_RTL (result,
5037 gen_rtx_MEM (DECL_MODE (result), DECL_RTL (parm)));
5039 set_mem_attributes (DECL_RTL (result), result, 1);
5043 /* Output all parameter conversion instructions (possibly including calls)
5044 now that all parameters have been copied out of hard registers. */
5045 emit_insns (conversion_insns);
5047 last_parm_insn = get_last_insn ();
5049 current_function_args_size = stack_args_size.constant;
5051 /* Adjust function incoming argument size for alignment and
5054 #ifdef REG_PARM_STACK_SPACE
5055 #ifndef MAYBE_REG_PARM_STACK_SPACE
5056 current_function_args_size = MAX (current_function_args_size,
5057 REG_PARM_STACK_SPACE (fndecl));
5061 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
5063 current_function_args_size
5064 = ((current_function_args_size + STACK_BYTES - 1)
5065 / STACK_BYTES) * STACK_BYTES;
5067 #ifdef ARGS_GROW_DOWNWARD
5068 current_function_arg_offset_rtx
5069 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
5070 : expand_expr (size_diffop (stack_args_size.var,
5071 size_int (-stack_args_size.constant)),
5072 NULL_RTX, VOIDmode, EXPAND_MEMORY_USE_BAD));
5074 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
5077 /* See how many bytes, if any, of its args a function should try to pop
5080 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
5081 current_function_args_size);
5083 /* For stdarg.h function, save info about
5084 regs and stack space used by the named args. */
5087 current_function_args_info = args_so_far;
5089 /* Set the rtx used for the function return value. Put this in its
5090 own variable so any optimizers that need this information don't have
5091 to include tree.h. Do this here so it gets done when an inlined
5092 function gets output. */
5094 current_function_return_rtx
5095 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
5096 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
5099 /* Indicate whether REGNO is an incoming argument to the current function
5100 that was promoted to a wider mode. If so, return the RTX for the
5101 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5102 that REGNO is promoted from and whether the promotion was signed or
5105 #ifdef PROMOTE_FUNCTION_ARGS
5108 promoted_input_arg (regno, pmode, punsignedp)
5110 enum machine_mode *pmode;
5115 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
5116 arg = TREE_CHAIN (arg))
5117 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
5118 && REGNO (DECL_INCOMING_RTL (arg)) == regno
5119 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
5121 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
5122 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
5124 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
5125 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
5126 && mode != DECL_MODE (arg))
5128 *pmode = DECL_MODE (arg);
5129 *punsignedp = unsignedp;
5130 return DECL_INCOMING_RTL (arg);
5139 /* Compute the size and offset from the start of the stacked arguments for a
5140 parm passed in mode PASSED_MODE and with type TYPE.
5142 INITIAL_OFFSET_PTR points to the current offset into the stacked
5145 The starting offset and size for this parm are returned in *OFFSET_PTR
5146 and *ARG_SIZE_PTR, respectively.
5148 IN_REGS is non-zero if the argument will be passed in registers. It will
5149 never be set if REG_PARM_STACK_SPACE is not defined.
5151 FNDECL is the function in which the argument was defined.
5153 There are two types of rounding that are done. The first, controlled by
5154 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5155 list to be aligned to the specific boundary (in bits). This rounding
5156 affects the initial and starting offsets, but not the argument size.
5158 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5159 optionally rounds the size of the parm to PARM_BOUNDARY. The
5160 initial offset is not affected by this rounding, while the size always
5161 is and the starting offset may be. */
5163 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
5164 initial_offset_ptr is positive because locate_and_pad_parm's
5165 callers pass in the total size of args so far as
5166 initial_offset_ptr. arg_size_ptr is always positive.*/
5169 locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
5170 initial_offset_ptr, offset_ptr, arg_size_ptr,
5172 enum machine_mode passed_mode;
5174 int in_regs ATTRIBUTE_UNUSED;
5175 tree fndecl ATTRIBUTE_UNUSED;
5176 struct args_size *initial_offset_ptr;
5177 struct args_size *offset_ptr;
5178 struct args_size *arg_size_ptr;
5179 struct args_size *alignment_pad;
5183 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5184 enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5185 int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5187 #ifdef REG_PARM_STACK_SPACE
5188 /* If we have found a stack parm before we reach the end of the
5189 area reserved for registers, skip that area. */
5192 int reg_parm_stack_space = 0;
5194 #ifdef MAYBE_REG_PARM_STACK_SPACE
5195 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
5197 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5199 if (reg_parm_stack_space > 0)
5201 if (initial_offset_ptr->var)
5203 initial_offset_ptr->var
5204 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5205 ssize_int (reg_parm_stack_space));
5206 initial_offset_ptr->constant = 0;
5208 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5209 initial_offset_ptr->constant = reg_parm_stack_space;
5212 #endif /* REG_PARM_STACK_SPACE */
5214 arg_size_ptr->var = 0;
5215 arg_size_ptr->constant = 0;
5216 alignment_pad->var = 0;
5217 alignment_pad->constant = 0;
5219 #ifdef ARGS_GROW_DOWNWARD
5220 if (initial_offset_ptr->var)
5222 offset_ptr->constant = 0;
5223 offset_ptr->var = size_binop (MINUS_EXPR, ssize_int (0),
5224 initial_offset_ptr->var);
5228 offset_ptr->constant = -initial_offset_ptr->constant;
5229 offset_ptr->var = 0;
5231 if (where_pad != none
5232 && (!host_integerp (sizetree, 1)
5233 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5234 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5235 SUB_PARM_SIZE (*offset_ptr, sizetree);
5236 if (where_pad != downward)
5237 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad);
5238 if (initial_offset_ptr->var)
5239 arg_size_ptr->var = size_binop (MINUS_EXPR,
5240 size_binop (MINUS_EXPR,
5242 initial_offset_ptr->var),
5246 arg_size_ptr->constant = (-initial_offset_ptr->constant
5247 - offset_ptr->constant);
5249 #else /* !ARGS_GROW_DOWNWARD */
5251 #ifdef REG_PARM_STACK_SPACE
5252 || REG_PARM_STACK_SPACE (fndecl) > 0
5255 pad_to_arg_alignment (initial_offset_ptr, boundary, alignment_pad);
5256 *offset_ptr = *initial_offset_ptr;
5258 #ifdef PUSH_ROUNDING
5259 if (passed_mode != BLKmode)
5260 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5263 /* Pad_below needs the pre-rounded size to know how much to pad below
5264 so this must be done before rounding up. */
5265 if (where_pad == downward
5266 /* However, BLKmode args passed in regs have their padding done elsewhere.
5267 The stack slot must be able to hold the entire register. */
5268 && !(in_regs && passed_mode == BLKmode))
5269 pad_below (offset_ptr, passed_mode, sizetree);
5271 if (where_pad != none
5272 && (!host_integerp (sizetree, 1)
5273 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5274 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5276 ADD_PARM_SIZE (*arg_size_ptr, sizetree);
5277 #endif /* ARGS_GROW_DOWNWARD */
5280 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5281 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5284 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad)
5285 struct args_size *offset_ptr;
5287 struct args_size *alignment_pad;
5289 tree save_var = NULL_TREE;
5290 HOST_WIDE_INT save_constant = 0;
5292 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5294 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5296 save_var = offset_ptr->var;
5297 save_constant = offset_ptr->constant;
5300 alignment_pad->var = NULL_TREE;
5301 alignment_pad->constant = 0;
5303 if (boundary > BITS_PER_UNIT)
5305 if (offset_ptr->var)
5308 #ifdef ARGS_GROW_DOWNWARD
5313 (ARGS_SIZE_TREE (*offset_ptr),
5314 boundary / BITS_PER_UNIT);
5315 offset_ptr->constant = 0; /*?*/
5316 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5317 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5322 offset_ptr->constant =
5323 #ifdef ARGS_GROW_DOWNWARD
5324 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
5326 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
5328 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5329 alignment_pad->constant = offset_ptr->constant - save_constant;
5334 #ifndef ARGS_GROW_DOWNWARD
5336 pad_below (offset_ptr, passed_mode, sizetree)
5337 struct args_size *offset_ptr;
5338 enum machine_mode passed_mode;
5341 if (passed_mode != BLKmode)
5343 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5344 offset_ptr->constant
5345 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5346 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5347 - GET_MODE_SIZE (passed_mode));
5351 if (TREE_CODE (sizetree) != INTEGER_CST
5352 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5354 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5355 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5357 ADD_PARM_SIZE (*offset_ptr, s2);
5358 SUB_PARM_SIZE (*offset_ptr, sizetree);
5364 /* Walk the tree of blocks describing the binding levels within a function
5365 and warn about uninitialized variables.
5366 This is done after calling flow_analysis and before global_alloc
5367 clobbers the pseudo-regs to hard regs. */
5370 uninitialized_vars_warning (block)
5373 register tree decl, sub;
5374 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5376 if (warn_uninitialized
5377 && TREE_CODE (decl) == VAR_DECL
5378 /* These warnings are unreliable for and aggregates
5379 because assigning the fields one by one can fail to convince
5380 flow.c that the entire aggregate was initialized.
5381 Unions are troublesome because members may be shorter. */
5382 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5383 && DECL_RTL (decl) != 0
5384 && GET_CODE (DECL_RTL (decl)) == REG
5385 /* Global optimizations can make it difficult to determine if a
5386 particular variable has been initialized. However, a VAR_DECL
5387 with a nonzero DECL_INITIAL had an initializer, so do not
5388 claim it is potentially uninitialized.
5390 We do not care about the actual value in DECL_INITIAL, so we do
5391 not worry that it may be a dangling pointer. */
5392 && DECL_INITIAL (decl) == NULL_TREE
5393 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5394 warning_with_decl (decl,
5395 "`%s' might be used uninitialized in this function");
5397 && TREE_CODE (decl) == VAR_DECL
5398 && DECL_RTL (decl) != 0
5399 && GET_CODE (DECL_RTL (decl)) == REG
5400 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5401 warning_with_decl (decl,
5402 "variable `%s' might be clobbered by `longjmp' or `vfork'");
5404 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5405 uninitialized_vars_warning (sub);
5408 /* Do the appropriate part of uninitialized_vars_warning
5409 but for arguments instead of local variables. */
5412 setjmp_args_warning ()
5415 for (decl = DECL_ARGUMENTS (current_function_decl);
5416 decl; decl = TREE_CHAIN (decl))
5417 if (DECL_RTL (decl) != 0
5418 && GET_CODE (DECL_RTL (decl)) == REG
5419 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5420 warning_with_decl (decl,
5421 "argument `%s' might be clobbered by `longjmp' or `vfork'");
5424 /* If this function call setjmp, put all vars into the stack
5425 unless they were declared `register'. */
5428 setjmp_protect (block)
5431 register tree decl, sub;
5432 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5433 if ((TREE_CODE (decl) == VAR_DECL
5434 || TREE_CODE (decl) == PARM_DECL)
5435 && DECL_RTL (decl) != 0
5436 && (GET_CODE (DECL_RTL (decl)) == REG
5437 || (GET_CODE (DECL_RTL (decl)) == MEM
5438 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5439 /* If this variable came from an inline function, it must be
5440 that its life doesn't overlap the setjmp. If there was a
5441 setjmp in the function, it would already be in memory. We
5442 must exclude such variable because their DECL_RTL might be
5443 set to strange things such as virtual_stack_vars_rtx. */
5444 && ! DECL_FROM_INLINE (decl)
5446 #ifdef NON_SAVING_SETJMP
5447 /* If longjmp doesn't restore the registers,
5448 don't put anything in them. */
5452 ! DECL_REGISTER (decl)))
5453 put_var_into_stack (decl);
5454 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5455 setjmp_protect (sub);
5458 /* Like the previous function, but for args instead of local variables. */
5461 setjmp_protect_args ()
5464 for (decl = DECL_ARGUMENTS (current_function_decl);
5465 decl; decl = TREE_CHAIN (decl))
5466 if ((TREE_CODE (decl) == VAR_DECL
5467 || TREE_CODE (decl) == PARM_DECL)
5468 && DECL_RTL (decl) != 0
5469 && (GET_CODE (DECL_RTL (decl)) == REG
5470 || (GET_CODE (DECL_RTL (decl)) == MEM
5471 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5473 /* If longjmp doesn't restore the registers,
5474 don't put anything in them. */
5475 #ifdef NON_SAVING_SETJMP
5479 ! DECL_REGISTER (decl)))
5480 put_var_into_stack (decl);
5483 /* Return the context-pointer register corresponding to DECL,
5484 or 0 if it does not need one. */
5487 lookup_static_chain (decl)
5490 tree context = decl_function_context (decl);
5494 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5497 /* We treat inline_function_decl as an alias for the current function
5498 because that is the inline function whose vars, types, etc.
5499 are being merged into the current function.
5500 See expand_inline_function. */
5501 if (context == current_function_decl || context == inline_function_decl)
5502 return virtual_stack_vars_rtx;
5504 for (link = context_display; link; link = TREE_CHAIN (link))
5505 if (TREE_PURPOSE (link) == context)
5506 return RTL_EXPR_RTL (TREE_VALUE (link));
5511 /* Convert a stack slot address ADDR for variable VAR
5512 (from a containing function)
5513 into an address valid in this function (using a static chain). */
5516 fix_lexical_addr (addr, var)
5521 HOST_WIDE_INT displacement;
5522 tree context = decl_function_context (var);
5523 struct function *fp;
5526 /* If this is the present function, we need not do anything. */
5527 if (context == current_function_decl || context == inline_function_decl)
5530 for (fp = outer_function_chain; fp; fp = fp->next)
5531 if (fp->decl == context)
5537 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5538 addr = XEXP (XEXP (addr, 0), 0);
5540 /* Decode given address as base reg plus displacement. */
5541 if (GET_CODE (addr) == REG)
5542 basereg = addr, displacement = 0;
5543 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5544 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5548 /* We accept vars reached via the containing function's
5549 incoming arg pointer and via its stack variables pointer. */
5550 if (basereg == fp->internal_arg_pointer)
5552 /* If reached via arg pointer, get the arg pointer value
5553 out of that function's stack frame.
5555 There are two cases: If a separate ap is needed, allocate a
5556 slot in the outer function for it and dereference it that way.
5557 This is correct even if the real ap is actually a pseudo.
5558 Otherwise, just adjust the offset from the frame pointer to
5561 #ifdef NEED_SEPARATE_AP
5564 if (fp->x_arg_pointer_save_area == 0)
5565 fp->x_arg_pointer_save_area
5566 = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, fp);
5568 addr = fix_lexical_addr (XEXP (fp->x_arg_pointer_save_area, 0), var);
5569 addr = memory_address (Pmode, addr);
5571 base = gen_rtx_MEM (Pmode, addr);
5572 MEM_ALIAS_SET (base) = get_frame_alias_set ();
5573 base = copy_to_reg (base);
5575 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5576 base = lookup_static_chain (var);
5580 else if (basereg == virtual_stack_vars_rtx)
5582 /* This is the same code as lookup_static_chain, duplicated here to
5583 avoid an extra call to decl_function_context. */
5586 for (link = context_display; link; link = TREE_CHAIN (link))
5587 if (TREE_PURPOSE (link) == context)
5589 base = RTL_EXPR_RTL (TREE_VALUE (link));
5597 /* Use same offset, relative to appropriate static chain or argument
5599 return plus_constant (base, displacement);
5602 /* Return the address of the trampoline for entering nested fn FUNCTION.
5603 If necessary, allocate a trampoline (in the stack frame)
5604 and emit rtl to initialize its contents (at entry to this function). */
5607 trampoline_address (function)
5613 struct function *fp;
5616 /* Find an existing trampoline and return it. */
5617 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5618 if (TREE_PURPOSE (link) == function)
5620 adjust_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5622 for (fp = outer_function_chain; fp; fp = fp->next)
5623 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5624 if (TREE_PURPOSE (link) == function)
5626 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5628 return adjust_trampoline_addr (tramp);
5631 /* None exists; we must make one. */
5633 /* Find the `struct function' for the function containing FUNCTION. */
5635 fn_context = decl_function_context (function);
5636 if (fn_context != current_function_decl
5637 && fn_context != inline_function_decl)
5638 for (fp = outer_function_chain; fp; fp = fp->next)
5639 if (fp->decl == fn_context)
5642 /* Allocate run-time space for this trampoline
5643 (usually in the defining function's stack frame). */
5644 #ifdef ALLOCATE_TRAMPOLINE
5645 tramp = ALLOCATE_TRAMPOLINE (fp);
5647 /* If rounding needed, allocate extra space
5648 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5649 #ifdef TRAMPOLINE_ALIGNMENT
5650 #define TRAMPOLINE_REAL_SIZE \
5651 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5653 #define TRAMPOLINE_REAL_SIZE (TRAMPOLINE_SIZE)
5655 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5659 /* Record the trampoline for reuse and note it for later initialization
5660 by expand_function_end. */
5663 rtlexp = make_node (RTL_EXPR);
5664 RTL_EXPR_RTL (rtlexp) = tramp;
5665 fp->x_trampoline_list = tree_cons (function, rtlexp,
5666 fp->x_trampoline_list);
5670 /* Make the RTL_EXPR node temporary, not momentary, so that the
5671 trampoline_list doesn't become garbage. */
5672 rtlexp = make_node (RTL_EXPR);
5674 RTL_EXPR_RTL (rtlexp) = tramp;
5675 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5678 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5679 return adjust_trampoline_addr (tramp);
5682 /* Given a trampoline address,
5683 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5686 round_trampoline_addr (tramp)
5689 #ifdef TRAMPOLINE_ALIGNMENT
5690 /* Round address up to desired boundary. */
5691 rtx temp = gen_reg_rtx (Pmode);
5692 temp = expand_binop (Pmode, add_optab, tramp,
5693 GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1),
5694 temp, 0, OPTAB_LIB_WIDEN);
5695 tramp = expand_binop (Pmode, and_optab, temp,
5696 GEN_INT (-TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT),
5697 temp, 0, OPTAB_LIB_WIDEN);
5702 /* Given a trampoline address, round it then apply any
5703 platform-specific adjustments so that the result can be used for a
5707 adjust_trampoline_addr (tramp)
5710 tramp = round_trampoline_addr (tramp);
5711 #ifdef TRAMPOLINE_ADJUST_ADDRESS
5712 TRAMPOLINE_ADJUST_ADDRESS (tramp);
5717 /* Put all this function's BLOCK nodes including those that are chained
5718 onto the first block into a vector, and return it.
5719 Also store in each NOTE for the beginning or end of a block
5720 the index of that block in the vector.
5721 The arguments are BLOCK, the chain of top-level blocks of the function,
5722 and INSNS, the insn chain of the function. */
5728 tree *block_vector, *last_block_vector;
5730 tree block = DECL_INITIAL (current_function_decl);
5735 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5736 depth-first order. */
5737 block_vector = get_block_vector (block, &n_blocks);
5738 block_stack = (tree *) xmalloc (n_blocks * sizeof (tree));
5740 last_block_vector = identify_blocks_1 (get_insns (),
5742 block_vector + n_blocks,
5745 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5746 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5747 if (0 && last_block_vector != block_vector + n_blocks)
5750 free (block_vector);
5754 /* Subroutine of identify_blocks. Do the block substitution on the
5755 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
5757 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5758 BLOCK_VECTOR is incremented for each block seen. */
5761 identify_blocks_1 (insns, block_vector, end_block_vector, orig_block_stack)
5764 tree *end_block_vector;
5765 tree *orig_block_stack;
5768 tree *block_stack = orig_block_stack;
5770 for (insn = insns; insn; insn = NEXT_INSN (insn))
5772 if (GET_CODE (insn) == NOTE)
5774 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5778 /* If there are more block notes than BLOCKs, something
5780 if (block_vector == end_block_vector)
5783 b = *block_vector++;
5784 NOTE_BLOCK (insn) = b;
5787 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5789 /* If there are more NOTE_INSN_BLOCK_ENDs than
5790 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
5791 if (block_stack == orig_block_stack)
5794 NOTE_BLOCK (insn) = *--block_stack;
5797 else if (GET_CODE (insn) == CALL_INSN
5798 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5800 rtx cp = PATTERN (insn);
5802 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
5803 end_block_vector, block_stack);
5805 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
5806 end_block_vector, block_stack);
5808 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
5809 end_block_vector, block_stack);
5813 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
5814 something is badly wrong. */
5815 if (block_stack != orig_block_stack)
5818 return block_vector;
5821 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
5822 and create duplicate blocks. */
5823 /* ??? Need an option to either create block fragments or to create
5824 abstract origin duplicates of a source block. It really depends
5825 on what optimization has been performed. */
5830 tree block = DECL_INITIAL (current_function_decl);
5831 varray_type block_stack;
5833 if (block == NULL_TREE)
5836 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
5838 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
5839 reorder_blocks_0 (block);
5841 /* Prune the old trees away, so that they don't get in the way. */
5842 BLOCK_SUBBLOCKS (block) = NULL_TREE;
5843 BLOCK_CHAIN (block) = NULL_TREE;
5845 /* Recreate the block tree from the note nesting. */
5846 reorder_blocks_1 (get_insns (), block, &block_stack);
5847 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
5849 /* Remove deleted blocks from the block fragment chains. */
5850 reorder_fix_fragments (block);
5852 VARRAY_FREE (block_stack);
5855 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
5858 reorder_blocks_0 (block)
5863 TREE_ASM_WRITTEN (block) = 0;
5864 reorder_blocks_0 (BLOCK_SUBBLOCKS (block));
5865 block = BLOCK_CHAIN (block);
5870 reorder_blocks_1 (insns, current_block, p_block_stack)
5873 varray_type *p_block_stack;
5877 for (insn = insns; insn; insn = NEXT_INSN (insn))
5879 if (GET_CODE (insn) == NOTE)
5881 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5883 tree block = NOTE_BLOCK (insn);
5885 /* If we have seen this block before, that means it now
5886 spans multiple address regions. Create a new fragment. */
5887 if (TREE_ASM_WRITTEN (block))
5889 tree new_block = copy_node (block);
5892 origin = (BLOCK_FRAGMENT_ORIGIN (block)
5893 ? BLOCK_FRAGMENT_ORIGIN (block)
5895 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
5896 BLOCK_FRAGMENT_CHAIN (new_block)
5897 = BLOCK_FRAGMENT_CHAIN (origin);
5898 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
5900 NOTE_BLOCK (insn) = new_block;
5904 BLOCK_SUBBLOCKS (block) = 0;
5905 TREE_ASM_WRITTEN (block) = 1;
5906 BLOCK_SUPERCONTEXT (block) = current_block;
5907 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
5908 BLOCK_SUBBLOCKS (current_block) = block;
5909 current_block = block;
5910 VARRAY_PUSH_TREE (*p_block_stack, block);
5912 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5914 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
5915 VARRAY_POP (*p_block_stack);
5916 BLOCK_SUBBLOCKS (current_block)
5917 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5918 current_block = BLOCK_SUPERCONTEXT (current_block);
5921 else if (GET_CODE (insn) == CALL_INSN
5922 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5924 rtx cp = PATTERN (insn);
5925 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
5927 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
5929 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
5934 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
5935 appears in the block tree, select one of the fragments to become
5936 the new origin block. */
5939 reorder_fix_fragments (block)
5944 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
5945 tree new_origin = NULL_TREE;
5949 if (! TREE_ASM_WRITTEN (dup_origin))
5951 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
5953 /* Find the first of the remaining fragments. There must
5954 be at least one -- the current block. */
5955 while (! TREE_ASM_WRITTEN (new_origin))
5956 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
5957 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
5960 else if (! dup_origin)
5963 /* Re-root the rest of the fragments to the new origin. In the
5964 case that DUP_ORIGIN was null, that means BLOCK was the origin
5965 of a chain of fragments and we want to remove those fragments
5966 that didn't make it to the output. */
5969 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
5974 if (TREE_ASM_WRITTEN (chain))
5976 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
5978 pp = &BLOCK_FRAGMENT_CHAIN (chain);
5980 chain = BLOCK_FRAGMENT_CHAIN (chain);
5985 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
5986 block = BLOCK_CHAIN (block);
5990 /* Reverse the order of elements in the chain T of blocks,
5991 and return the new head of the chain (old last element). */
5997 register tree prev = 0, decl, next;
5998 for (decl = t; decl; decl = next)
6000 next = BLOCK_CHAIN (decl);
6001 BLOCK_CHAIN (decl) = prev;
6007 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
6008 non-NULL, list them all into VECTOR, in a depth-first preorder
6009 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
6013 all_blocks (block, vector)
6021 TREE_ASM_WRITTEN (block) = 0;
6023 /* Record this block. */
6025 vector[n_blocks] = block;
6029 /* Record the subblocks, and their subblocks... */
6030 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
6031 vector ? vector + n_blocks : 0);
6032 block = BLOCK_CHAIN (block);
6038 /* Return a vector containing all the blocks rooted at BLOCK. The
6039 number of elements in the vector is stored in N_BLOCKS_P. The
6040 vector is dynamically allocated; it is the caller's responsibility
6041 to call `free' on the pointer returned. */
6044 get_block_vector (block, n_blocks_p)
6050 *n_blocks_p = all_blocks (block, NULL);
6051 block_vector = (tree *) xmalloc (*n_blocks_p * sizeof (tree));
6052 all_blocks (block, block_vector);
6054 return block_vector;
6057 static int next_block_index = 2;
6059 /* Set BLOCK_NUMBER for all the blocks in FN. */
6069 /* For SDB and XCOFF debugging output, we start numbering the blocks
6070 from 1 within each function, rather than keeping a running
6072 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6073 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
6074 next_block_index = 1;
6077 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
6079 /* The top-level BLOCK isn't numbered at all. */
6080 for (i = 1; i < n_blocks; ++i)
6081 /* We number the blocks from two. */
6082 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
6084 free (block_vector);
6089 /* Allocate a function structure and reset its contents to the defaults. */
6091 prepare_function_start ()
6093 cfun = (struct function *) xcalloc (1, sizeof (struct function));
6095 init_stmt_for_function ();
6096 init_eh_for_function ();
6098 cse_not_expected = ! optimize;
6100 /* Caller save not needed yet. */
6101 caller_save_needed = 0;
6103 /* No stack slots have been made yet. */
6104 stack_slot_list = 0;
6106 current_function_has_nonlocal_label = 0;
6107 current_function_has_nonlocal_goto = 0;
6109 /* There is no stack slot for handling nonlocal gotos. */
6110 nonlocal_goto_handler_slots = 0;
6111 nonlocal_goto_stack_level = 0;
6113 /* No labels have been declared for nonlocal use. */
6114 nonlocal_labels = 0;
6115 nonlocal_goto_handler_labels = 0;
6117 /* No function calls so far in this function. */
6118 function_call_count = 0;
6120 /* No parm regs have been allocated.
6121 (This is important for output_inline_function.) */
6122 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
6124 /* Initialize the RTL mechanism. */
6127 /* Initialize the queue of pending postincrement and postdecrements,
6128 and some other info in expr.c. */
6131 /* We haven't done register allocation yet. */
6134 init_varasm_status (cfun);
6136 /* Clear out data used for inlining. */
6137 cfun->inlinable = 0;
6138 cfun->original_decl_initial = 0;
6139 cfun->original_arg_vector = 0;
6141 cfun->stack_alignment_needed = STACK_BOUNDARY;
6142 cfun->preferred_stack_boundary = STACK_BOUNDARY;
6144 /* Set if a call to setjmp is seen. */
6145 current_function_calls_setjmp = 0;
6147 /* Set if a call to longjmp is seen. */
6148 current_function_calls_longjmp = 0;
6150 current_function_calls_alloca = 0;
6151 current_function_contains_functions = 0;
6152 current_function_is_leaf = 0;
6153 current_function_nothrow = 0;
6154 current_function_sp_is_unchanging = 0;
6155 current_function_uses_only_leaf_regs = 0;
6156 current_function_has_computed_jump = 0;
6157 current_function_is_thunk = 0;
6159 current_function_returns_pcc_struct = 0;
6160 current_function_returns_struct = 0;
6161 current_function_epilogue_delay_list = 0;
6162 current_function_uses_const_pool = 0;
6163 current_function_uses_pic_offset_table = 0;
6164 current_function_cannot_inline = 0;
6166 /* We have not yet needed to make a label to jump to for tail-recursion. */
6167 tail_recursion_label = 0;
6169 /* We haven't had a need to make a save area for ap yet. */
6170 arg_pointer_save_area = 0;
6172 /* No stack slots allocated yet. */
6175 /* No SAVE_EXPRs in this function yet. */
6178 /* No RTL_EXPRs in this function yet. */
6181 /* Set up to allocate temporaries. */
6184 /* Indicate that we need to distinguish between the return value of the
6185 present function and the return value of a function being called. */
6186 rtx_equal_function_value_matters = 1;
6188 /* Indicate that we have not instantiated virtual registers yet. */
6189 virtuals_instantiated = 0;
6191 /* Indicate that we want CONCATs now. */
6192 generating_concat_p = 1;
6194 /* Indicate we have no need of a frame pointer yet. */
6195 frame_pointer_needed = 0;
6197 /* By default assume not varargs or stdarg. */
6198 current_function_varargs = 0;
6199 current_function_stdarg = 0;
6201 /* We haven't made any trampolines for this function yet. */
6202 trampoline_list = 0;
6204 init_pending_stack_adjust ();
6205 inhibit_defer_pop = 0;
6207 current_function_outgoing_args_size = 0;
6209 if (init_lang_status)
6210 (*init_lang_status) (cfun);
6211 if (init_machine_status)
6212 (*init_machine_status) (cfun);
6215 /* Initialize the rtl expansion mechanism so that we can do simple things
6216 like generate sequences. This is used to provide a context during global
6217 initialization of some passes. */
6219 init_dummy_function_start ()
6221 prepare_function_start ();
6224 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6225 and initialize static variables for generating RTL for the statements
6229 init_function_start (subr, filename, line)
6231 const char *filename;
6234 prepare_function_start ();
6236 /* Remember this function for later. */
6237 cfun->next_global = all_functions;
6238 all_functions = cfun;
6240 current_function_name = (*decl_printable_name) (subr, 2);
6243 /* Nonzero if this is a nested function that uses a static chain. */
6245 current_function_needs_context
6246 = (decl_function_context (current_function_decl) != 0
6247 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
6249 /* Within function body, compute a type's size as soon it is laid out. */
6250 immediate_size_expand++;
6252 /* Prevent ever trying to delete the first instruction of a function.
6253 Also tell final how to output a linenum before the function prologue.
6254 Note linenums could be missing, e.g. when compiling a Java .class file. */
6256 emit_line_note (filename, line);
6258 /* Make sure first insn is a note even if we don't want linenums.
6259 This makes sure the first insn will never be deleted.
6260 Also, final expects a note to appear there. */
6261 emit_note (NULL, NOTE_INSN_DELETED);
6263 /* Set flags used by final.c. */
6264 if (aggregate_value_p (DECL_RESULT (subr)))
6266 #ifdef PCC_STATIC_STRUCT_RETURN
6267 current_function_returns_pcc_struct = 1;
6269 current_function_returns_struct = 1;
6272 /* Warn if this value is an aggregate type,
6273 regardless of which calling convention we are using for it. */
6274 if (warn_aggregate_return
6275 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6276 warning ("function returns an aggregate");
6278 current_function_returns_pointer
6279 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
6282 /* Make sure all values used by the optimization passes have sane
6285 init_function_for_compilation ()
6289 /* No prologue/epilogue insns yet. */
6290 VARRAY_GROW (prologue, 0);
6291 VARRAY_GROW (epilogue, 0);
6292 VARRAY_GROW (sibcall_epilogue, 0);
6295 /* Indicate that the current function uses extra args
6296 not explicitly mentioned in the argument list in any fashion. */
6301 current_function_varargs = 1;
6304 /* Expand a call to __main at the beginning of a possible main function. */
6306 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6307 #undef HAS_INIT_SECTION
6308 #define HAS_INIT_SECTION
6312 expand_main_function ()
6314 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
6315 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
6317 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
6320 /* Forcably align the stack. */
6321 #ifdef STACK_GROWS_DOWNWARD
6322 tmp = expand_binop (Pmode, and_optab, stack_pointer_rtx,
6323 GEN_INT (-align), stack_pointer_rtx, 1, OPTAB_WIDEN);
6325 tmp = expand_binop (Pmode, add_optab, stack_pointer_rtx,
6326 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
6327 tmp = expand_binop (Pmode, and_optab, tmp, GEN_INT (-align),
6328 stack_pointer_rtx, 1, OPTAB_WIDEN);
6330 if (tmp != stack_pointer_rtx)
6331 emit_move_insn (stack_pointer_rtx, tmp);
6333 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
6334 tmp = force_reg (Pmode, const0_rtx);
6335 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
6339 #ifndef HAS_INIT_SECTION
6340 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, NAME__MAIN), 0,
6345 extern struct obstack permanent_obstack;
6347 /* The PENDING_SIZES represent the sizes of variable-sized types.
6348 Create RTL for the various sizes now (using temporary variables),
6349 so that we can refer to the sizes from the RTL we are generating
6350 for the current function. The PENDING_SIZES are a TREE_LIST. The
6351 TREE_VALUE of each node is a SAVE_EXPR. */
6354 expand_pending_sizes (pending_sizes)
6359 /* Evaluate now the sizes of any types declared among the arguments. */
6360 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
6362 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode,
6363 EXPAND_MEMORY_USE_BAD);
6364 /* Flush the queue in case this parameter declaration has
6370 /* Start the RTL for a new function, and set variables used for
6372 SUBR is the FUNCTION_DECL node.
6373 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6374 the function's parameters, which must be run at any return statement. */
6377 expand_function_start (subr, parms_have_cleanups)
6379 int parms_have_cleanups;
6382 rtx last_ptr = NULL_RTX;
6384 /* Make sure volatile mem refs aren't considered
6385 valid operands of arithmetic insns. */
6386 init_recog_no_volatile ();
6388 /* Set this before generating any memory accesses. */
6389 current_function_check_memory_usage
6390 = (flag_check_memory_usage
6391 && ! DECL_NO_CHECK_MEMORY_USAGE (current_function_decl));
6393 current_function_instrument_entry_exit
6394 = (flag_instrument_function_entry_exit
6395 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6397 current_function_limit_stack
6398 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6400 /* If function gets a static chain arg, store it in the stack frame.
6401 Do this first, so it gets the first stack slot offset. */
6402 if (current_function_needs_context)
6404 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
6406 /* Delay copying static chain if it is not a register to avoid
6407 conflicts with regs used for parameters. */
6408 if (! SMALL_REGISTER_CLASSES
6409 || GET_CODE (static_chain_incoming_rtx) == REG)
6410 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6413 /* If the parameters of this function need cleaning up, get a label
6414 for the beginning of the code which executes those cleanups. This must
6415 be done before doing anything with return_label. */
6416 if (parms_have_cleanups)
6417 cleanup_label = gen_label_rtx ();
6421 /* Make the label for return statements to jump to. Do not special
6422 case machines with special return instructions -- they will be
6423 handled later during jump, ifcvt, or epilogue creation. */
6424 return_label = gen_label_rtx ();
6426 /* Initialize rtx used to return the value. */
6427 /* Do this before assign_parms so that we copy the struct value address
6428 before any library calls that assign parms might generate. */
6430 /* Decide whether to return the value in memory or in a register. */
6431 if (aggregate_value_p (DECL_RESULT (subr)))
6433 /* Returning something that won't go in a register. */
6434 register rtx value_address = 0;
6436 #ifdef PCC_STATIC_STRUCT_RETURN
6437 if (current_function_returns_pcc_struct)
6439 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6440 value_address = assemble_static_space (size);
6445 /* Expect to be passed the address of a place to store the value.
6446 If it is passed as an argument, assign_parms will take care of
6448 if (struct_value_incoming_rtx)
6450 value_address = gen_reg_rtx (Pmode);
6451 emit_move_insn (value_address, struct_value_incoming_rtx);
6456 SET_DECL_RTL (DECL_RESULT (subr),
6457 gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)),
6459 set_mem_attributes (DECL_RTL (DECL_RESULT (subr)),
6460 DECL_RESULT (subr), 1);
6463 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6464 /* If return mode is void, this decl rtl should not be used. */
6465 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
6468 /* Compute the return values into a pseudo reg, which we will copy
6469 into the true return register after the cleanups are done. */
6471 /* In order to figure out what mode to use for the pseudo, we
6472 figure out what the mode of the eventual return register will
6473 actually be, and use that. */
6475 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
6478 /* Structures that are returned in registers are not aggregate_value_p,
6479 so we may see a PARALLEL. Don't play pseudo games with this. */
6480 if (! REG_P (hard_reg))
6481 SET_DECL_RTL (DECL_RESULT (subr), hard_reg);
6484 /* Create the pseudo. */
6485 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg)));
6487 /* Needed because we may need to move this to memory
6488 in case it's a named return value whose address is taken. */
6489 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6493 /* Initialize rtx for parameters and local variables.
6494 In some cases this requires emitting insns. */
6496 assign_parms (subr);
6498 /* Copy the static chain now if it wasn't a register. The delay is to
6499 avoid conflicts with the parameter passing registers. */
6501 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6502 if (GET_CODE (static_chain_incoming_rtx) != REG)
6503 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6505 /* The following was moved from init_function_start.
6506 The move is supposed to make sdb output more accurate. */
6507 /* Indicate the beginning of the function body,
6508 as opposed to parm setup. */
6509 emit_note (NULL, NOTE_INSN_FUNCTION_BEG);
6511 if (GET_CODE (get_last_insn ()) != NOTE)
6512 emit_note (NULL, NOTE_INSN_DELETED);
6513 parm_birth_insn = get_last_insn ();
6515 context_display = 0;
6516 if (current_function_needs_context)
6518 /* Fetch static chain values for containing functions. */
6519 tem = decl_function_context (current_function_decl);
6520 /* Copy the static chain pointer into a pseudo. If we have
6521 small register classes, copy the value from memory if
6522 static_chain_incoming_rtx is a REG. */
6525 /* If the static chain originally came in a register, put it back
6526 there, then move it out in the next insn. The reason for
6527 this peculiar code is to satisfy function integration. */
6528 if (SMALL_REGISTER_CLASSES
6529 && GET_CODE (static_chain_incoming_rtx) == REG)
6530 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6531 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6536 tree rtlexp = make_node (RTL_EXPR);
6538 RTL_EXPR_RTL (rtlexp) = last_ptr;
6539 context_display = tree_cons (tem, rtlexp, context_display);
6540 tem = decl_function_context (tem);
6543 /* Chain thru stack frames, assuming pointer to next lexical frame
6544 is found at the place we always store it. */
6545 #ifdef FRAME_GROWS_DOWNWARD
6546 last_ptr = plus_constant (last_ptr,
6547 -(HOST_WIDE_INT) GET_MODE_SIZE (Pmode));
6549 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr));
6550 MEM_ALIAS_SET (last_ptr) = get_frame_alias_set ();
6551 last_ptr = copy_to_reg (last_ptr);
6553 /* If we are not optimizing, ensure that we know that this
6554 piece of context is live over the entire function. */
6556 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6561 if (current_function_instrument_entry_exit)
6563 rtx fun = DECL_RTL (current_function_decl);
6564 if (GET_CODE (fun) == MEM)
6565 fun = XEXP (fun, 0);
6568 emit_library_call (profile_function_entry_libfunc, 0, VOIDmode, 2,
6570 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6572 hard_frame_pointer_rtx),
6578 PROFILE_HOOK (profile_label_no);
6581 /* After the display initializations is where the tail-recursion label
6582 should go, if we end up needing one. Ensure we have a NOTE here
6583 since some things (like trampolines) get placed before this. */
6584 tail_recursion_reentry = emit_note (NULL, NOTE_INSN_DELETED);
6586 /* Evaluate now the sizes of any types declared among the arguments. */
6587 expand_pending_sizes (nreverse (get_pending_sizes ()));
6589 /* Make sure there is a line number after the function entry setup code. */
6590 force_next_line_note ();
6593 /* Undo the effects of init_dummy_function_start. */
6595 expand_dummy_function_end ()
6597 /* End any sequences that failed to be closed due to syntax errors. */
6598 while (in_sequence_p ())
6601 /* Outside function body, can't compute type's actual size
6602 until next function's body starts. */
6604 free_after_parsing (cfun);
6605 free_after_compilation (cfun);
6610 /* Call DOIT for each hard register used as a return value from
6611 the current function. */
6614 diddle_return_value (doit, arg)
6615 void (*doit) PARAMS ((rtx, void *));
6618 rtx outgoing = current_function_return_rtx;
6623 if (GET_CODE (outgoing) == REG)
6624 (*doit) (outgoing, arg);
6625 else if (GET_CODE (outgoing) == PARALLEL)
6629 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6631 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6633 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6640 do_clobber_return_reg (reg, arg)
6642 void *arg ATTRIBUTE_UNUSED;
6644 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6648 clobber_return_register ()
6650 diddle_return_value (do_clobber_return_reg, NULL);
6652 /* In case we do use pseudo to return value, clobber it too. */
6653 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6655 tree decl_result = DECL_RESULT (current_function_decl);
6656 rtx decl_rtl = DECL_RTL (decl_result);
6657 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
6659 do_clobber_return_reg (decl_rtl, NULL);
6665 do_use_return_reg (reg, arg)
6667 void *arg ATTRIBUTE_UNUSED;
6669 emit_insn (gen_rtx_USE (VOIDmode, reg));
6673 use_return_register ()
6675 diddle_return_value (do_use_return_reg, NULL);
6678 /* Generate RTL for the end of the current function.
6679 FILENAME and LINE are the current position in the source file.
6681 It is up to language-specific callers to do cleanups for parameters--
6682 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
6685 expand_function_end (filename, line, end_bindings)
6686 const char *filename;
6693 #ifdef TRAMPOLINE_TEMPLATE
6694 static rtx initial_trampoline;
6697 finish_expr_for_function ();
6699 #ifdef NON_SAVING_SETJMP
6700 /* Don't put any variables in registers if we call setjmp
6701 on a machine that fails to restore the registers. */
6702 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6704 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6705 setjmp_protect (DECL_INITIAL (current_function_decl));
6707 setjmp_protect_args ();
6711 /* Save the argument pointer if a save area was made for it. */
6712 if (arg_pointer_save_area)
6714 /* arg_pointer_save_area may not be a valid memory address, so we
6715 have to check it and fix it if necessary. */
6718 emit_move_insn (validize_mem (arg_pointer_save_area),
6719 virtual_incoming_args_rtx);
6720 seq = gen_sequence ();
6722 emit_insn_before (seq, tail_recursion_reentry);
6725 /* Initialize any trampolines required by this function. */
6726 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6728 tree function = TREE_PURPOSE (link);
6729 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6730 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6731 #ifdef TRAMPOLINE_TEMPLATE
6736 #ifdef TRAMPOLINE_TEMPLATE
6737 /* First make sure this compilation has a template for
6738 initializing trampolines. */
6739 if (initial_trampoline == 0)
6742 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6744 ggc_add_rtx_root (&initial_trampoline, 1);
6748 /* Generate insns to initialize the trampoline. */
6750 tramp = round_trampoline_addr (XEXP (tramp, 0));
6751 #ifdef TRAMPOLINE_TEMPLATE
6752 blktramp = change_address (initial_trampoline, BLKmode, tramp);
6753 emit_block_move (blktramp, initial_trampoline,
6754 GEN_INT (TRAMPOLINE_SIZE),
6755 TRAMPOLINE_ALIGNMENT);
6757 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6761 /* Put those insns at entry to the containing function (this one). */
6762 emit_insns_before (seq, tail_recursion_reentry);
6765 /* If we are doing stack checking and this function makes calls,
6766 do a stack probe at the start of the function to ensure we have enough
6767 space for another stack frame. */
6768 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6772 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6773 if (GET_CODE (insn) == CALL_INSN)
6776 probe_stack_range (STACK_CHECK_PROTECT,
6777 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6780 emit_insns_before (seq, tail_recursion_reentry);
6785 /* Warn about unused parms if extra warnings were specified. */
6786 /* Either ``-W -Wunused'' or ``-Wunused-parameter'' enables this
6787 warning. WARN_UNUSED_PARAMETER is negative when set by
6789 if (warn_unused_parameter > 0
6790 || (warn_unused_parameter < 0 && extra_warnings))
6794 for (decl = DECL_ARGUMENTS (current_function_decl);
6795 decl; decl = TREE_CHAIN (decl))
6796 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6797 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6798 warning_with_decl (decl, "unused parameter `%s'");
6801 /* Delete handlers for nonlocal gotos if nothing uses them. */
6802 if (nonlocal_goto_handler_slots != 0
6803 && ! current_function_has_nonlocal_label)
6806 /* End any sequences that failed to be closed due to syntax errors. */
6807 while (in_sequence_p ())
6810 /* Outside function body, can't compute type's actual size
6811 until next function's body starts. */
6812 immediate_size_expand--;
6814 clear_pending_stack_adjust ();
6815 do_pending_stack_adjust ();
6817 /* Mark the end of the function body.
6818 If control reaches this insn, the function can drop through
6819 without returning a value. */
6820 emit_note (NULL, NOTE_INSN_FUNCTION_END);
6822 /* Must mark the last line number note in the function, so that the test
6823 coverage code can avoid counting the last line twice. This just tells
6824 the code to ignore the immediately following line note, since there
6825 already exists a copy of this note somewhere above. This line number
6826 note is still needed for debugging though, so we can't delete it. */
6827 if (flag_test_coverage)
6828 emit_note (NULL, NOTE_INSN_REPEATED_LINE_NUMBER);
6830 /* Output a linenumber for the end of the function.
6831 SDB depends on this. */
6832 emit_line_note_force (filename, line);
6834 /* Before the return label (if any), clobber the return
6835 registers so that they are not propogated live to the rest of
6836 the function. This can only happen with functions that drop
6837 through; if there had been a return statement, there would
6838 have either been a return rtx, or a jump to the return label.
6840 We delay actual code generation after the current_function_value_rtx
6842 clobber_after = get_last_insn ();
6844 /* Output the label for the actual return from the function,
6845 if one is expected. This happens either because a function epilogue
6846 is used instead of a return instruction, or because a return was done
6847 with a goto in order to run local cleanups, or because of pcc-style
6848 structure returning. */
6850 emit_label (return_label);
6852 /* C++ uses this. */
6854 expand_end_bindings (0, 0, 0);
6856 if (current_function_instrument_entry_exit)
6858 rtx fun = DECL_RTL (current_function_decl);
6859 if (GET_CODE (fun) == MEM)
6860 fun = XEXP (fun, 0);
6863 emit_library_call (profile_function_exit_libfunc, 0, VOIDmode, 2,
6865 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6867 hard_frame_pointer_rtx),
6871 /* Let except.c know where it should emit the call to unregister
6872 the function context for sjlj exceptions. */
6873 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
6874 sjlj_emit_function_exit_after (get_last_insn ());
6876 /* If we had calls to alloca, and this machine needs
6877 an accurate stack pointer to exit the function,
6878 insert some code to save and restore the stack pointer. */
6879 #ifdef EXIT_IGNORE_STACK
6880 if (! EXIT_IGNORE_STACK)
6882 if (current_function_calls_alloca)
6886 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
6887 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
6890 /* If scalar return value was computed in a pseudo-reg, or was a named
6891 return value that got dumped to the stack, copy that to the hard
6893 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6895 tree decl_result = DECL_RESULT (current_function_decl);
6896 rtx decl_rtl = DECL_RTL (decl_result);
6898 if (REG_P (decl_rtl)
6899 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
6900 : DECL_REGISTER (decl_result))
6904 #ifdef FUNCTION_OUTGOING_VALUE
6905 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
6906 current_function_decl);
6908 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
6909 current_function_decl);
6911 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
6913 /* If this is a BLKmode structure being returned in registers,
6914 then use the mode computed in expand_return. Note that if
6915 decl_rtl is memory, then its mode may have been changed,
6916 but that current_function_return_rtx has not. */
6917 if (GET_MODE (real_decl_rtl) == BLKmode)
6918 PUT_MODE (real_decl_rtl, GET_MODE (current_function_return_rtx));
6920 /* If a named return value dumped decl_return to memory, then
6921 we may need to re-do the PROMOTE_MODE signed/unsigned
6923 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
6925 int unsignedp = TREE_UNSIGNED (TREE_TYPE (decl_result));
6927 #ifdef PROMOTE_FUNCTION_RETURN
6928 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
6932 convert_move (real_decl_rtl, decl_rtl, unsignedp);
6934 else if (GET_CODE (real_decl_rtl) == PARALLEL)
6935 emit_group_load (real_decl_rtl, decl_rtl,
6936 int_size_in_bytes (TREE_TYPE (decl_result)),
6937 TYPE_ALIGN (TREE_TYPE (decl_result)));
6939 emit_move_insn (real_decl_rtl, decl_rtl);
6941 /* The delay slot scheduler assumes that current_function_return_rtx
6942 holds the hard register containing the return value, not a
6943 temporary pseudo. */
6944 current_function_return_rtx = real_decl_rtl;
6948 /* If returning a structure, arrange to return the address of the value
6949 in a place where debuggers expect to find it.
6951 If returning a structure PCC style,
6952 the caller also depends on this value.
6953 And current_function_returns_pcc_struct is not necessarily set. */
6954 if (current_function_returns_struct
6955 || current_function_returns_pcc_struct)
6958 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
6959 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
6960 #ifdef FUNCTION_OUTGOING_VALUE
6962 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
6963 current_function_decl);
6966 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
6969 /* Mark this as a function return value so integrate will delete the
6970 assignment and USE below when inlining this function. */
6971 REG_FUNCTION_VALUE_P (outgoing) = 1;
6973 #ifdef POINTERS_EXTEND_UNSIGNED
6974 /* The address may be ptr_mode and OUTGOING may be Pmode. */
6975 if (GET_MODE (outgoing) != GET_MODE (value_address))
6976 value_address = convert_memory_address (GET_MODE (outgoing),
6980 emit_move_insn (outgoing, value_address);
6982 /* Show return register used to hold result (in this case the address
6984 current_function_return_rtx = outgoing;
6987 /* If this is an implementation of throw, do what's necessary to
6988 communicate between __builtin_eh_return and the epilogue. */
6989 expand_eh_return ();
6991 /* Emit the actual code to clobber return register. */
6996 clobber_return_register ();
6997 seq = gen_sequence ();
7000 after = emit_insn_after (seq, clobber_after);
7002 if (clobber_after != after)
7003 cfun->x_clobber_return_insn = after;
7006 /* ??? This should no longer be necessary since stupid is no longer with
7007 us, but there are some parts of the compiler (eg reload_combine, and
7008 sh mach_dep_reorg) that still try and compute their own lifetime info
7009 instead of using the general framework. */
7010 use_return_register ();
7012 /* Fix up any gotos that jumped out to the outermost
7013 binding level of the function.
7014 Must follow emitting RETURN_LABEL. */
7016 /* If you have any cleanups to do at this point,
7017 and they need to create temporary variables,
7018 then you will lose. */
7019 expand_fixups (get_insns ());
7022 /* Extend a vector that records the INSN_UIDs of INSNS (either a
7023 sequence or a single insn). */
7026 record_insns (insns, vecp)
7030 if (GET_CODE (insns) == SEQUENCE)
7032 int len = XVECLEN (insns, 0);
7033 int i = VARRAY_SIZE (*vecp);
7035 VARRAY_GROW (*vecp, i + len);
7038 VARRAY_INT (*vecp, i) = INSN_UID (XVECEXP (insns, 0, len));
7044 int i = VARRAY_SIZE (*vecp);
7045 VARRAY_GROW (*vecp, i + 1);
7046 VARRAY_INT (*vecp, i) = INSN_UID (insns);
7050 /* Determine how many INSN_UIDs in VEC are part of INSN. */
7053 contains (insn, vec)
7059 if (GET_CODE (insn) == INSN
7060 && GET_CODE (PATTERN (insn)) == SEQUENCE)
7063 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
7064 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7065 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
7071 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7072 if (INSN_UID (insn) == VARRAY_INT (vec, j))
7079 prologue_epilogue_contains (insn)
7082 if (contains (insn, prologue))
7084 if (contains (insn, epilogue))
7090 sibcall_epilogue_contains (insn)
7093 if (sibcall_epilogue)
7094 return contains (insn, sibcall_epilogue);
7099 /* Insert gen_return at the end of block BB. This also means updating
7100 block_for_insn appropriately. */
7103 emit_return_into_block (bb, line_note)
7109 p = NEXT_INSN (bb->end);
7110 end = emit_jump_insn_after (gen_return (), bb->end);
7112 emit_line_note_after (NOTE_SOURCE_FILE (line_note),
7113 NOTE_LINE_NUMBER (line_note), bb->end);
7117 set_block_for_insn (p, bb);
7124 #endif /* HAVE_return */
7126 #ifdef HAVE_epilogue
7128 /* Modify SEQ, a SEQUENCE that is part of the epilogue, to no modifications
7129 to the stack pointer. */
7132 keep_stack_depressed (seq)
7136 rtx sp_from_reg = 0;
7137 int sp_modified_unknown = 0;
7139 /* If the epilogue is just a single instruction, it's OK as is */
7141 if (GET_CODE (seq) != SEQUENCE)
7144 /* Scan all insns in SEQ looking for ones that modified the stack
7145 pointer. Record if it modified the stack pointer by copying it
7146 from the frame pointer or if it modified it in some other way.
7147 Then modify any subsequent stack pointer references to take that
7148 into account. We start by only allowing SP to be copied from a
7149 register (presumably FP) and then be subsequently referenced. */
7151 for (i = 0; i < XVECLEN (seq, 0); i++)
7153 rtx insn = XVECEXP (seq, 0, i);
7155 if (GET_RTX_CLASS (GET_CODE (insn)) != 'i')
7158 if (reg_set_p (stack_pointer_rtx, insn))
7160 rtx set = single_set (insn);
7162 /* If SP is set as a side-effect, we can't support this. */
7166 if (GET_CODE (SET_SRC (set)) == REG)
7167 sp_from_reg = SET_SRC (set);
7169 sp_modified_unknown = 1;
7171 /* Don't allow the SP modification to happen. */
7172 PUT_CODE (insn, NOTE);
7173 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
7174 NOTE_SOURCE_FILE (insn) = 0;
7176 else if (reg_referenced_p (stack_pointer_rtx, PATTERN (insn)))
7178 if (sp_modified_unknown)
7181 else if (sp_from_reg != 0)
7183 = replace_rtx (PATTERN (insn), stack_pointer_rtx, sp_from_reg);
7189 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7190 this into place with notes indicating where the prologue ends and where
7191 the epilogue begins. Update the basic block information when possible. */
7194 thread_prologue_and_epilogue_insns (f)
7195 rtx f ATTRIBUTE_UNUSED;
7200 #ifdef HAVE_prologue
7201 rtx prologue_end = NULL_RTX;
7203 #if defined (HAVE_epilogue) || defined(HAVE_return)
7204 rtx epilogue_end = NULL_RTX;
7207 #ifdef HAVE_prologue
7211 seq = gen_prologue ();
7214 /* Retain a map of the prologue insns. */
7215 if (GET_CODE (seq) != SEQUENCE)
7217 record_insns (seq, &prologue);
7218 prologue_end = emit_note (NULL, NOTE_INSN_PROLOGUE_END);
7220 seq = gen_sequence ();
7223 /* Can't deal with multiple successsors of the entry block
7224 at the moment. Function should always have at least one
7226 if (!ENTRY_BLOCK_PTR->succ || ENTRY_BLOCK_PTR->succ->succ_next)
7229 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
7234 /* If the exit block has no non-fake predecessors, we don't need
7236 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7237 if ((e->flags & EDGE_FAKE) == 0)
7243 if (optimize && HAVE_return)
7245 /* If we're allowed to generate a simple return instruction,
7246 then by definition we don't need a full epilogue. Examine
7247 the block that falls through to EXIT. If it does not
7248 contain any code, examine its predecessors and try to
7249 emit (conditional) return instructions. */
7255 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7256 if (e->flags & EDGE_FALLTHRU)
7262 /* Verify that there are no active instructions in the last block. */
7264 while (label && GET_CODE (label) != CODE_LABEL)
7266 if (active_insn_p (label))
7268 label = PREV_INSN (label);
7271 if (last->head == label && GET_CODE (label) == CODE_LABEL)
7273 rtx epilogue_line_note = NULL_RTX;
7275 /* Locate the line number associated with the closing brace,
7276 if we can find one. */
7277 for (seq = get_last_insn ();
7278 seq && ! active_insn_p (seq);
7279 seq = PREV_INSN (seq))
7280 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
7282 epilogue_line_note = seq;
7286 for (e = last->pred; e; e = e_next)
7288 basic_block bb = e->src;
7291 e_next = e->pred_next;
7292 if (bb == ENTRY_BLOCK_PTR)
7296 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
7299 /* If we have an unconditional jump, we can replace that
7300 with a simple return instruction. */
7301 if (simplejump_p (jump))
7303 emit_return_into_block (bb, epilogue_line_note);
7304 flow_delete_insn (jump);
7307 /* If we have a conditional jump, we can try to replace
7308 that with a conditional return instruction. */
7309 else if (condjump_p (jump))
7313 ret = SET_SRC (PATTERN (jump));
7314 if (GET_CODE (XEXP (ret, 1)) == LABEL_REF)
7315 loc = &XEXP (ret, 1);
7317 loc = &XEXP (ret, 2);
7318 ret = gen_rtx_RETURN (VOIDmode);
7320 if (! validate_change (jump, loc, ret, 0))
7322 if (JUMP_LABEL (jump))
7323 LABEL_NUSES (JUMP_LABEL (jump))--;
7325 /* If this block has only one successor, it both jumps
7326 and falls through to the fallthru block, so we can't
7328 if (bb->succ->succ_next == NULL)
7334 /* Fix up the CFG for the successful change we just made. */
7335 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7338 /* Emit a return insn for the exit fallthru block. Whether
7339 this is still reachable will be determined later. */
7341 emit_barrier_after (last->end);
7342 emit_return_into_block (last, epilogue_line_note);
7343 epilogue_end = last->end;
7348 #ifdef HAVE_epilogue
7351 /* Find the edge that falls through to EXIT. Other edges may exist
7352 due to RETURN instructions, but those don't need epilogues.
7353 There really shouldn't be a mixture -- either all should have
7354 been converted or none, however... */
7356 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7357 if (e->flags & EDGE_FALLTHRU)
7363 epilogue_end = emit_note (NULL, NOTE_INSN_EPILOGUE_BEG);
7365 seq = gen_epilogue ();
7367 /* If this function returns with the stack depressed, massage
7368 the epilogue to actually do that. */
7369 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7370 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7371 keep_stack_depressed (seq);
7373 emit_jump_insn (seq);
7375 /* Retain a map of the epilogue insns. */
7376 if (GET_CODE (seq) != SEQUENCE)
7378 record_insns (seq, &epilogue);
7380 seq = gen_sequence ();
7383 insert_insn_on_edge (seq, e);
7390 commit_edge_insertions ();
7392 #ifdef HAVE_sibcall_epilogue
7393 /* Emit sibling epilogues before any sibling call sites. */
7394 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7396 basic_block bb = e->src;
7401 if (GET_CODE (insn) != CALL_INSN
7402 || ! SIBLING_CALL_P (insn))
7406 seq = gen_sibcall_epilogue ();
7409 i = PREV_INSN (insn);
7410 newinsn = emit_insn_before (seq, insn);
7412 /* Update the UID to basic block map. */
7413 for (i = NEXT_INSN (i); i != insn; i = NEXT_INSN (i))
7414 set_block_for_insn (i, bb);
7416 /* Retain a map of the epilogue insns. Used in life analysis to
7417 avoid getting rid of sibcall epilogue insns. */
7418 record_insns (GET_CODE (seq) == SEQUENCE
7419 ? seq : newinsn, &sibcall_epilogue);
7423 #ifdef HAVE_prologue
7428 /* GDB handles `break f' by setting a breakpoint on the first
7429 line note after the prologue. Which means (1) that if
7430 there are line number notes before where we inserted the
7431 prologue we should move them, and (2) we should generate a
7432 note before the end of the first basic block, if there isn't
7435 ??? This behaviour is completely broken when dealing with
7436 multiple entry functions. We simply place the note always
7437 into first basic block and let alternate entry points
7441 for (insn = prologue_end; insn; insn = prev)
7443 prev = PREV_INSN (insn);
7444 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7446 /* Note that we cannot reorder the first insn in the
7447 chain, since rest_of_compilation relies on that
7448 remaining constant. */
7451 reorder_insns (insn, insn, prologue_end);
7455 /* Find the last line number note in the first block. */
7456 for (insn = BASIC_BLOCK (0)->end;
7457 insn != prologue_end && insn;
7458 insn = PREV_INSN (insn))
7459 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7462 /* If we didn't find one, make a copy of the first line number
7466 for (insn = next_active_insn (prologue_end);
7468 insn = PREV_INSN (insn))
7469 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7471 emit_line_note_after (NOTE_SOURCE_FILE (insn),
7472 NOTE_LINE_NUMBER (insn),
7479 #ifdef HAVE_epilogue
7484 /* Similarly, move any line notes that appear after the epilogue.
7485 There is no need, however, to be quite so anal about the existance
7487 for (insn = epilogue_end; insn; insn = next)
7489 next = NEXT_INSN (insn);
7490 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7491 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7497 /* Reposition the prologue-end and epilogue-begin notes after instruction
7498 scheduling and delayed branch scheduling. */
7501 reposition_prologue_and_epilogue_notes (f)
7502 rtx f ATTRIBUTE_UNUSED;
7504 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7507 if ((len = VARRAY_SIZE (prologue)) > 0)
7509 register rtx insn, note = 0;
7511 /* Scan from the beginning until we reach the last prologue insn.
7512 We apparently can't depend on basic_block_{head,end} after
7514 for (insn = f; len && insn; insn = NEXT_INSN (insn))
7516 if (GET_CODE (insn) == NOTE)
7518 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
7521 else if ((len -= contains (insn, prologue)) == 0)
7524 /* Find the prologue-end note if we haven't already, and
7525 move it to just after the last prologue insn. */
7528 for (note = insn; (note = NEXT_INSN (note));)
7529 if (GET_CODE (note) == NOTE
7530 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
7534 next = NEXT_INSN (note);
7536 /* Whether or not we can depend on BLOCK_HEAD,
7537 attempt to keep it up-to-date. */
7538 if (BLOCK_HEAD (0) == note)
7539 BLOCK_HEAD (0) = next;
7542 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
7543 if (GET_CODE (insn) == CODE_LABEL)
7544 insn = NEXT_INSN (insn);
7545 add_insn_after (note, insn);
7550 if ((len = VARRAY_SIZE (epilogue)) > 0)
7552 register rtx insn, note = 0;
7554 /* Scan from the end until we reach the first epilogue insn.
7555 We apparently can't depend on basic_block_{head,end} after
7557 for (insn = get_last_insn (); len && insn; insn = PREV_INSN (insn))
7559 if (GET_CODE (insn) == NOTE)
7561 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
7564 else if ((len -= contains (insn, epilogue)) == 0)
7566 /* Find the epilogue-begin note if we haven't already, and
7567 move it to just before the first epilogue insn. */
7570 for (note = insn; (note = PREV_INSN (note));)
7571 if (GET_CODE (note) == NOTE
7572 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
7576 /* Whether or not we can depend on BLOCK_HEAD,
7577 attempt to keep it up-to-date. */
7579 && BLOCK_HEAD (n_basic_blocks-1) == insn)
7580 BLOCK_HEAD (n_basic_blocks-1) = note;
7583 add_insn_before (note, insn);
7587 #endif /* HAVE_prologue or HAVE_epilogue */
7590 /* Mark T for GC. */
7594 struct temp_slot *t;
7598 ggc_mark_rtx (t->slot);
7599 ggc_mark_rtx (t->address);
7600 ggc_mark_tree (t->rtl_expr);
7601 ggc_mark_tree (t->type);
7607 /* Mark P for GC. */
7610 mark_function_status (p)
7619 ggc_mark_rtx (p->arg_offset_rtx);
7621 if (p->x_parm_reg_stack_loc)
7622 for (i = p->x_max_parm_reg, r = p->x_parm_reg_stack_loc;
7626 ggc_mark_rtx (p->return_rtx);
7627 ggc_mark_rtx (p->x_cleanup_label);
7628 ggc_mark_rtx (p->x_return_label);
7629 ggc_mark_rtx (p->x_save_expr_regs);
7630 ggc_mark_rtx (p->x_stack_slot_list);
7631 ggc_mark_rtx (p->x_parm_birth_insn);
7632 ggc_mark_rtx (p->x_tail_recursion_label);
7633 ggc_mark_rtx (p->x_tail_recursion_reentry);
7634 ggc_mark_rtx (p->internal_arg_pointer);
7635 ggc_mark_rtx (p->x_arg_pointer_save_area);
7636 ggc_mark_tree (p->x_rtl_expr_chain);
7637 ggc_mark_rtx (p->x_last_parm_insn);
7638 ggc_mark_tree (p->x_context_display);
7639 ggc_mark_tree (p->x_trampoline_list);
7640 ggc_mark_rtx (p->epilogue_delay_list);
7641 ggc_mark_rtx (p->x_clobber_return_insn);
7643 mark_temp_slot (p->x_temp_slots);
7646 struct var_refs_queue *q = p->fixup_var_refs_queue;
7649 ggc_mark_rtx (q->modified);
7654 ggc_mark_rtx (p->x_nonlocal_goto_handler_slots);
7655 ggc_mark_rtx (p->x_nonlocal_goto_handler_labels);
7656 ggc_mark_rtx (p->x_nonlocal_goto_stack_level);
7657 ggc_mark_tree (p->x_nonlocal_labels);
7659 mark_hard_reg_initial_vals (p);
7662 /* Mark the function chain ARG (which is really a struct function **)
7666 mark_function_chain (arg)
7669 struct function *f = *(struct function **) arg;
7671 for (; f; f = f->next_global)
7673 ggc_mark_tree (f->decl);
7675 mark_function_status (f);
7676 mark_eh_status (f->eh);
7677 mark_stmt_status (f->stmt);
7678 mark_expr_status (f->expr);
7679 mark_emit_status (f->emit);
7680 mark_varasm_status (f->varasm);
7682 if (mark_machine_status)
7683 (*mark_machine_status) (f);
7684 if (mark_lang_status)
7685 (*mark_lang_status) (f);
7687 if (f->original_arg_vector)
7688 ggc_mark_rtvec ((rtvec) f->original_arg_vector);
7689 if (f->original_decl_initial)
7690 ggc_mark_tree (f->original_decl_initial);
7694 /* Called once, at initialization, to initialize function.c. */
7697 init_function_once ()
7699 ggc_add_root (&all_functions, 1, sizeof all_functions,
7700 mark_function_chain);
7702 VARRAY_INT_INIT (prologue, 0, "prologue");
7703 VARRAY_INT_INIT (epilogue, 0, "epilogue");
7704 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");