1 /* Expands front end tree to back end RTL for GNU C-Compiler
2 Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
5 This file is part of GNU CC.
7 GNU CC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GNU CC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU CC; see the file COPYING. If not, write to
19 the Free Software Foundation, 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
22 /* This file handles the generation of rtl code from tree structure
23 at the level of the function as a whole.
24 It creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 `expand_function_start' is called at the beginning of a function,
28 before the function body is parsed, and `expand_function_end' is
29 called after parsing the body.
31 Call `assign_stack_local' to allocate a stack slot for a local variable.
32 This is usually done during the RTL generation for the function body,
33 but it can also be done in the reload pass when a pseudo-register does
34 not get a hard register.
36 Call `put_var_into_stack' when you learn, belatedly, that a variable
37 previously given a pseudo-register must in fact go in the stack.
38 This function changes the DECL_RTL to be a stack slot instead of a reg
39 then scans all the RTL instructions so far generated to correct them. */
50 #include "hard-reg-set.h"
51 #include "insn-config.h"
54 #include "basic-block.h"
60 #include "integrate.h"
62 #ifndef TRAMPOLINE_ALIGNMENT
63 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
66 #ifndef LOCAL_ALIGNMENT
67 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
70 #if !defined (PREFERRED_STACK_BOUNDARY) && defined (STACK_BOUNDARY)
71 #define PREFERRED_STACK_BOUNDARY STACK_BOUNDARY
74 /* Some systems use __main in a way incompatible with its use in gcc, in these
75 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
76 give the same symbol without quotes for an alternative entry point. You
77 must define both, or neither. */
79 #define NAME__MAIN "__main"
80 #define SYMBOL__MAIN __main
83 /* Round a value to the lowest integer less than it that is a multiple of
84 the required alignment. Avoid using division in case the value is
85 negative. Assume the alignment is a power of two. */
86 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
88 /* Similar, but round to the next highest integer that meets the
90 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
92 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
93 during rtl generation. If they are different register numbers, this is
94 always true. It may also be true if
95 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
96 generation. See fix_lexical_addr for details. */
98 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
99 #define NEED_SEPARATE_AP
102 /* Nonzero if function being compiled doesn't contain any calls
103 (ignoring the prologue and epilogue). This is set prior to
104 local register allocation and is valid for the remaining
106 int current_function_is_leaf;
108 /* Nonzero if function being compiled doesn't contain any instructions
109 that can throw an exception. This is set prior to final. */
111 int current_function_nothrow;
113 /* Nonzero if function being compiled doesn't modify the stack pointer
114 (ignoring the prologue and epilogue). This is only valid after
115 life_analysis has run. */
116 int current_function_sp_is_unchanging;
118 /* Nonzero if the function being compiled is a leaf function which only
119 uses leaf registers. This is valid after reload (specifically after
120 sched2) and is useful only if the port defines LEAF_REGISTERS. */
121 int current_function_uses_only_leaf_regs;
123 /* Nonzero once virtual register instantiation has been done.
124 assign_stack_local uses frame_pointer_rtx when this is nonzero.
125 calls.c:emit_library_call_value_1 uses it to set up
126 post-instantiation libcalls. */
127 int virtuals_instantiated;
129 /* These variables hold pointers to functions to create and destroy
130 target specific, per-function data structures. */
131 void (*init_machine_status) PARAMS ((struct function *));
132 void (*free_machine_status) PARAMS ((struct function *));
133 /* This variable holds a pointer to a function to register any
134 data items in the target specific, per-function data structure
135 that will need garbage collection. */
136 void (*mark_machine_status) PARAMS ((struct function *));
138 /* Likewise, but for language-specific data. */
139 void (*init_lang_status) PARAMS ((struct function *));
140 void (*save_lang_status) PARAMS ((struct function *));
141 void (*restore_lang_status) PARAMS ((struct function *));
142 void (*mark_lang_status) PARAMS ((struct function *));
143 void (*free_lang_status) PARAMS ((struct function *));
145 /* The FUNCTION_DECL for an inline function currently being expanded. */
146 tree inline_function_decl;
148 /* The currently compiled function. */
149 struct function *cfun = 0;
151 /* Global list of all compiled functions. */
152 struct function *all_functions = 0;
154 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
155 static varray_type prologue;
156 static varray_type epilogue;
158 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
160 static varray_type sibcall_epilogue;
162 /* In order to evaluate some expressions, such as function calls returning
163 structures in memory, we need to temporarily allocate stack locations.
164 We record each allocated temporary in the following structure.
166 Associated with each temporary slot is a nesting level. When we pop up
167 one level, all temporaries associated with the previous level are freed.
168 Normally, all temporaries are freed after the execution of the statement
169 in which they were created. However, if we are inside a ({...}) grouping,
170 the result may be in a temporary and hence must be preserved. If the
171 result could be in a temporary, we preserve it if we can determine which
172 one it is in. If we cannot determine which temporary may contain the
173 result, all temporaries are preserved. A temporary is preserved by
174 pretending it was allocated at the previous nesting level.
176 Automatic variables are also assigned temporary slots, at the nesting
177 level where they are defined. They are marked a "kept" so that
178 free_temp_slots will not free them. */
182 /* Points to next temporary slot. */
183 struct temp_slot *next;
184 /* The rtx to used to reference the slot. */
186 /* The rtx used to represent the address if not the address of the
187 slot above. May be an EXPR_LIST if multiple addresses exist. */
189 /* The alignment (in bits) of the slot. */
191 /* The size, in units, of the slot. */
193 /* The type of the object in the slot, or zero if it doesn't correspond
194 to a type. We use this to determine whether a slot can be reused.
195 It can be reused if objects of the type of the new slot will always
196 conflict with objects of the type of the old slot. */
198 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
200 /* Non-zero if this temporary is currently in use. */
202 /* Non-zero if this temporary has its address taken. */
204 /* Nesting level at which this slot is being used. */
206 /* Non-zero if this should survive a call to free_temp_slots. */
208 /* The offset of the slot from the frame_pointer, including extra space
209 for alignment. This info is for combine_temp_slots. */
210 HOST_WIDE_INT base_offset;
211 /* The size of the slot, including extra space for alignment. This
212 info is for combine_temp_slots. */
213 HOST_WIDE_INT full_size;
216 /* This structure is used to record MEMs or pseudos used to replace VAR, any
217 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
218 maintain this list in case two operands of an insn were required to match;
219 in that case we must ensure we use the same replacement. */
221 struct fixup_replacement
225 struct fixup_replacement *next;
228 struct insns_for_mem_entry {
229 /* The KEY in HE will be a MEM. */
230 struct hash_entry he;
231 /* These are the INSNS which reference the MEM. */
235 /* Forward declarations. */
237 static rtx assign_stack_local_1 PARAMS ((enum machine_mode, HOST_WIDE_INT,
238 int, struct function *));
239 static rtx assign_stack_temp_for_type PARAMS ((enum machine_mode,
240 HOST_WIDE_INT, int, tree));
241 static struct temp_slot *find_temp_slot_from_address PARAMS ((rtx));
242 static void put_reg_into_stack PARAMS ((struct function *, rtx, tree,
243 enum machine_mode, enum machine_mode,
244 int, unsigned int, int,
245 struct hash_table *));
246 static void schedule_fixup_var_refs PARAMS ((struct function *, rtx, tree,
248 struct hash_table *));
249 static void fixup_var_refs PARAMS ((rtx, enum machine_mode, int,
250 struct hash_table *));
251 static struct fixup_replacement
252 *find_fixup_replacement PARAMS ((struct fixup_replacement **, rtx));
253 static void fixup_var_refs_insns PARAMS ((rtx, rtx, enum machine_mode,
255 static void fixup_var_refs_insns_with_hash
256 PARAMS ((struct hash_table *, rtx,
257 enum machine_mode, int));
258 static void fixup_var_refs_insn PARAMS ((rtx, rtx, enum machine_mode,
260 static void fixup_var_refs_1 PARAMS ((rtx, enum machine_mode, rtx *, rtx,
261 struct fixup_replacement **));
262 static rtx fixup_memory_subreg PARAMS ((rtx, rtx, int));
263 static rtx walk_fixup_memory_subreg PARAMS ((rtx, rtx, int));
264 static rtx fixup_stack_1 PARAMS ((rtx, rtx));
265 static void optimize_bit_field PARAMS ((rtx, rtx, rtx *));
266 static void instantiate_decls PARAMS ((tree, int));
267 static void instantiate_decls_1 PARAMS ((tree, int));
268 static void instantiate_decl PARAMS ((rtx, HOST_WIDE_INT, int));
269 static rtx instantiate_new_reg PARAMS ((rtx, HOST_WIDE_INT *));
270 static int instantiate_virtual_regs_1 PARAMS ((rtx *, rtx, int));
271 static void delete_handlers PARAMS ((void));
272 static void pad_to_arg_alignment PARAMS ((struct args_size *, int,
273 struct args_size *));
274 #ifndef ARGS_GROW_DOWNWARD
275 static void pad_below PARAMS ((struct args_size *, enum machine_mode,
278 static rtx round_trampoline_addr PARAMS ((rtx));
279 static rtx adjust_trampoline_addr PARAMS ((rtx));
280 static tree *identify_blocks_1 PARAMS ((rtx, tree *, tree *, tree *));
281 static void reorder_blocks_0 PARAMS ((rtx));
282 static void reorder_blocks_1 PARAMS ((rtx, tree, varray_type *));
283 static tree blocks_nreverse PARAMS ((tree));
284 static int all_blocks PARAMS ((tree, tree *));
285 static tree *get_block_vector PARAMS ((tree, int *));
286 /* We always define `record_insns' even if its not used so that we
287 can always export `prologue_epilogue_contains'. */
288 static void record_insns PARAMS ((rtx, varray_type *)) ATTRIBUTE_UNUSED;
289 static int contains PARAMS ((rtx, varray_type));
291 static void emit_return_into_block PARAMS ((basic_block, rtx));
293 static void put_addressof_into_stack PARAMS ((rtx, struct hash_table *));
294 static bool purge_addressof_1 PARAMS ((rtx *, rtx, int, int,
295 struct hash_table *));
296 static void purge_single_hard_subreg_set PARAMS ((rtx));
298 static void keep_stack_depressed PARAMS ((rtx));
300 static int is_addressof PARAMS ((rtx *, void *));
301 static struct hash_entry *insns_for_mem_newfunc PARAMS ((struct hash_entry *,
304 static unsigned long insns_for_mem_hash PARAMS ((hash_table_key));
305 static bool insns_for_mem_comp PARAMS ((hash_table_key, hash_table_key));
306 static int insns_for_mem_walk PARAMS ((rtx *, void *));
307 static void compute_insns_for_mem PARAMS ((rtx, rtx, struct hash_table *));
308 static void mark_temp_slot PARAMS ((struct temp_slot *));
309 static void mark_function_status PARAMS ((struct function *));
310 static void mark_function_chain PARAMS ((void *));
311 static void prepare_function_start PARAMS ((void));
312 static void do_clobber_return_reg PARAMS ((rtx, void *));
313 static void do_use_return_reg PARAMS ((rtx, void *));
315 /* Pointer to chain of `struct function' for containing functions. */
316 struct function *outer_function_chain;
318 /* Given a function decl for a containing function,
319 return the `struct function' for it. */
322 find_function_data (decl)
327 for (p = outer_function_chain; p; p = p->next)
334 /* Save the current context for compilation of a nested function.
335 This is called from language-specific code. The caller should use
336 the save_lang_status callback to save any language-specific state,
337 since this function knows only about language-independent
341 push_function_context_to (context)
344 struct function *p, *context_data;
348 context_data = (context == current_function_decl
350 : find_function_data (context));
351 context_data->contains_functions = 1;
355 init_dummy_function_start ();
358 p->next = outer_function_chain;
359 outer_function_chain = p;
360 p->fixup_var_refs_queue = 0;
362 if (save_lang_status)
363 (*save_lang_status) (p);
369 push_function_context ()
371 push_function_context_to (current_function_decl);
374 /* Restore the last saved context, at the end of a nested function.
375 This function is called from language-specific code. */
378 pop_function_context_from (context)
379 tree context ATTRIBUTE_UNUSED;
381 struct function *p = outer_function_chain;
382 struct var_refs_queue *queue;
383 struct var_refs_queue *next;
386 outer_function_chain = p->next;
388 current_function_decl = p->decl;
391 restore_emit_status (p);
393 if (restore_lang_status)
394 (*restore_lang_status) (p);
396 /* Finish doing put_var_into_stack for any of our variables
397 which became addressable during the nested function. */
398 for (queue = p->fixup_var_refs_queue; queue; queue = next)
401 fixup_var_refs (queue->modified, queue->promoted_mode,
402 queue->unsignedp, 0);
405 p->fixup_var_refs_queue = 0;
407 /* Reset variables that have known state during rtx generation. */
408 rtx_equal_function_value_matters = 1;
409 virtuals_instantiated = 0;
410 generating_concat_p = 1;
414 pop_function_context ()
416 pop_function_context_from (current_function_decl);
419 /* Clear out all parts of the state in F that can safely be discarded
420 after the function has been parsed, but not compiled, to let
421 garbage collection reclaim the memory. */
424 free_after_parsing (f)
427 /* f->expr->forced_labels is used by code generation. */
428 /* f->emit->regno_reg_rtx is used by code generation. */
429 /* f->varasm is used by code generation. */
430 /* f->eh->eh_return_stub_label is used by code generation. */
432 if (free_lang_status)
433 (*free_lang_status) (f);
434 free_stmt_status (f);
437 /* Clear out all parts of the state in F that can safely be discarded
438 after the function has been compiled, to let garbage collection
439 reclaim the memory. */
442 free_after_compilation (f)
445 struct temp_slot *ts;
446 struct temp_slot *next;
449 free_expr_status (f);
450 free_emit_status (f);
451 free_varasm_status (f);
453 if (free_machine_status)
454 (*free_machine_status) (f);
456 if (f->x_parm_reg_stack_loc)
457 free (f->x_parm_reg_stack_loc);
459 for (ts = f->x_temp_slots; ts; ts = next)
464 f->x_temp_slots = NULL;
466 f->arg_offset_rtx = NULL;
467 f->return_rtx = NULL;
468 f->internal_arg_pointer = NULL;
469 f->x_nonlocal_labels = NULL;
470 f->x_nonlocal_goto_handler_slots = NULL;
471 f->x_nonlocal_goto_handler_labels = NULL;
472 f->x_nonlocal_goto_stack_level = NULL;
473 f->x_cleanup_label = NULL;
474 f->x_return_label = NULL;
475 f->x_save_expr_regs = NULL;
476 f->x_stack_slot_list = NULL;
477 f->x_rtl_expr_chain = NULL;
478 f->x_tail_recursion_label = NULL;
479 f->x_tail_recursion_reentry = NULL;
480 f->x_arg_pointer_save_area = NULL;
481 f->x_clobber_return_insn = NULL;
482 f->x_context_display = NULL;
483 f->x_trampoline_list = NULL;
484 f->x_parm_birth_insn = NULL;
485 f->x_last_parm_insn = NULL;
486 f->x_parm_reg_stack_loc = NULL;
487 f->fixup_var_refs_queue = NULL;
488 f->original_arg_vector = NULL;
489 f->original_decl_initial = NULL;
490 f->inl_last_parm_insn = NULL;
491 f->epilogue_delay_list = NULL;
494 /* Allocate fixed slots in the stack frame of the current function. */
496 /* Return size needed for stack frame based on slots so far allocated in
498 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
499 the caller may have to do that. */
502 get_func_frame_size (f)
505 #ifdef FRAME_GROWS_DOWNWARD
506 return -f->x_frame_offset;
508 return f->x_frame_offset;
512 /* Return size needed for stack frame based on slots so far allocated.
513 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
514 the caller may have to do that. */
518 return get_func_frame_size (cfun);
521 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
522 with machine mode MODE.
524 ALIGN controls the amount of alignment for the address of the slot:
525 0 means according to MODE,
526 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
527 positive specifies alignment boundary in bits.
529 We do not round to stack_boundary here.
531 FUNCTION specifies the function to allocate in. */
534 assign_stack_local_1 (mode, size, align, function)
535 enum machine_mode mode;
538 struct function *function;
540 register rtx x, addr;
541 int bigend_correction = 0;
549 alignment = BIGGEST_ALIGNMENT;
551 alignment = GET_MODE_ALIGNMENT (mode);
553 /* Allow the target to (possibly) increase the alignment of this
555 type = type_for_mode (mode, 0);
557 alignment = LOCAL_ALIGNMENT (type, alignment);
559 alignment /= BITS_PER_UNIT;
561 else if (align == -1)
563 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
564 size = CEIL_ROUND (size, alignment);
567 alignment = align / BITS_PER_UNIT;
569 #ifdef FRAME_GROWS_DOWNWARD
570 function->x_frame_offset -= size;
573 /* Ignore alignment we can't do with expected alignment of the boundary. */
574 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
575 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
577 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
578 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
580 /* Round frame offset to that alignment.
581 We must be careful here, since FRAME_OFFSET might be negative and
582 division with a negative dividend isn't as well defined as we might
583 like. So we instead assume that ALIGNMENT is a power of two and
584 use logical operations which are unambiguous. */
585 #ifdef FRAME_GROWS_DOWNWARD
586 function->x_frame_offset = FLOOR_ROUND (function->x_frame_offset, alignment);
588 function->x_frame_offset = CEIL_ROUND (function->x_frame_offset, alignment);
591 /* On a big-endian machine, if we are allocating more space than we will use,
592 use the least significant bytes of those that are allocated. */
593 if (BYTES_BIG_ENDIAN && mode != BLKmode)
594 bigend_correction = size - GET_MODE_SIZE (mode);
596 /* If we have already instantiated virtual registers, return the actual
597 address relative to the frame pointer. */
598 if (function == cfun && virtuals_instantiated)
599 addr = plus_constant (frame_pointer_rtx,
600 (frame_offset + bigend_correction
601 + STARTING_FRAME_OFFSET));
603 addr = plus_constant (virtual_stack_vars_rtx,
604 function->x_frame_offset + bigend_correction);
606 #ifndef FRAME_GROWS_DOWNWARD
607 function->x_frame_offset += size;
610 x = gen_rtx_MEM (mode, addr);
612 function->x_stack_slot_list
613 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
618 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
622 assign_stack_local (mode, size, align)
623 enum machine_mode mode;
627 return assign_stack_local_1 (mode, size, align, cfun);
630 /* Allocate a temporary stack slot and record it for possible later
633 MODE is the machine mode to be given to the returned rtx.
635 SIZE is the size in units of the space required. We do no rounding here
636 since assign_stack_local will do any required rounding.
638 KEEP is 1 if this slot is to be retained after a call to
639 free_temp_slots. Automatic variables for a block are allocated
640 with this flag. KEEP is 2 if we allocate a longer term temporary,
641 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
642 if we are to allocate something at an inner level to be treated as
643 a variable in the block (e.g., a SAVE_EXPR).
645 TYPE is the type that will be used for the stack slot. */
648 assign_stack_temp_for_type (mode, size, keep, type)
649 enum machine_mode mode;
655 struct temp_slot *p, *best_p = 0;
657 /* If SIZE is -1 it means that somebody tried to allocate a temporary
658 of a variable size. */
663 align = BIGGEST_ALIGNMENT;
665 align = GET_MODE_ALIGNMENT (mode);
668 type = type_for_mode (mode, 0);
671 align = LOCAL_ALIGNMENT (type, align);
673 /* Try to find an available, already-allocated temporary of the proper
674 mode which meets the size and alignment requirements. Choose the
675 smallest one with the closest alignment. */
676 for (p = temp_slots; p; p = p->next)
677 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
679 && objects_must_conflict_p (p->type, type)
680 && (best_p == 0 || best_p->size > p->size
681 || (best_p->size == p->size && best_p->align > p->align)))
683 if (p->align == align && p->size == size)
691 /* Make our best, if any, the one to use. */
694 /* If there are enough aligned bytes left over, make them into a new
695 temp_slot so that the extra bytes don't get wasted. Do this only
696 for BLKmode slots, so that we can be sure of the alignment. */
697 if (GET_MODE (best_p->slot) == BLKmode)
699 int alignment = best_p->align / BITS_PER_UNIT;
700 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
702 if (best_p->size - rounded_size >= alignment)
704 p = (struct temp_slot *) xmalloc (sizeof (struct temp_slot));
705 p->in_use = p->addr_taken = 0;
706 p->size = best_p->size - rounded_size;
707 p->base_offset = best_p->base_offset + rounded_size;
708 p->full_size = best_p->full_size - rounded_size;
709 p->slot = gen_rtx_MEM (BLKmode,
710 plus_constant (XEXP (best_p->slot, 0),
712 p->align = best_p->align;
715 p->type = best_p->type;
716 p->next = temp_slots;
719 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
722 best_p->size = rounded_size;
723 best_p->full_size = rounded_size;
730 /* If we still didn't find one, make a new temporary. */
733 HOST_WIDE_INT frame_offset_old = frame_offset;
735 p = (struct temp_slot *) xmalloc (sizeof (struct temp_slot));
737 /* We are passing an explicit alignment request to assign_stack_local.
738 One side effect of that is assign_stack_local will not round SIZE
739 to ensure the frame offset remains suitably aligned.
741 So for requests which depended on the rounding of SIZE, we go ahead
742 and round it now. We also make sure ALIGNMENT is at least
743 BIGGEST_ALIGNMENT. */
744 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
746 p->slot = assign_stack_local (mode,
748 ? CEIL_ROUND (size, align / BITS_PER_UNIT)
754 /* The following slot size computation is necessary because we don't
755 know the actual size of the temporary slot until assign_stack_local
756 has performed all the frame alignment and size rounding for the
757 requested temporary. Note that extra space added for alignment
758 can be either above or below this stack slot depending on which
759 way the frame grows. We include the extra space if and only if it
760 is above this slot. */
761 #ifdef FRAME_GROWS_DOWNWARD
762 p->size = frame_offset_old - frame_offset;
767 /* Now define the fields used by combine_temp_slots. */
768 #ifdef FRAME_GROWS_DOWNWARD
769 p->base_offset = frame_offset;
770 p->full_size = frame_offset_old - frame_offset;
772 p->base_offset = frame_offset_old;
773 p->full_size = frame_offset - frame_offset_old;
776 p->next = temp_slots;
782 p->rtl_expr = seq_rtl_expr;
787 p->level = target_temp_slot_level;
792 p->level = var_temp_slot_level;
797 p->level = temp_slot_level;
801 /* We may be reusing an old slot, so clear any MEM flags that may have been
803 RTX_UNCHANGING_P (p->slot) = 0;
804 MEM_IN_STRUCT_P (p->slot) = 0;
805 MEM_SCALAR_P (p->slot) = 0;
806 MEM_VOLATILE_P (p->slot) = 0;
808 /* If we know the alias set for the memory that will be used, use
809 it. If there's no TYPE, then we don't know anything about the
810 alias set for the memory. */
812 MEM_ALIAS_SET (p->slot) = get_alias_set (type);
814 MEM_ALIAS_SET (p->slot) = 0;
816 /* If a type is specified, set the relevant flags. */
819 RTX_UNCHANGING_P (p->slot) = TYPE_READONLY (type);
820 MEM_VOLATILE_P (p->slot) = TYPE_VOLATILE (type);
821 MEM_SET_IN_STRUCT_P (p->slot, AGGREGATE_TYPE_P (type));
827 /* Allocate a temporary stack slot and record it for possible later
828 reuse. First three arguments are same as in preceding function. */
831 assign_stack_temp (mode, size, keep)
832 enum machine_mode mode;
836 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
839 /* Assign a temporary of given TYPE.
840 KEEP is as for assign_stack_temp.
841 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
842 it is 0 if a register is OK.
843 DONT_PROMOTE is 1 if we should not promote values in register
847 assign_temp (type, keep, memory_required, dont_promote)
851 int dont_promote ATTRIBUTE_UNUSED;
853 enum machine_mode mode = TYPE_MODE (type);
854 #ifndef PROMOTE_FOR_CALL_ONLY
855 int unsignedp = TREE_UNSIGNED (type);
858 if (mode == BLKmode || memory_required)
860 HOST_WIDE_INT size = int_size_in_bytes (type);
863 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
864 problems with allocating the stack space. */
868 /* Unfortunately, we don't yet know how to allocate variable-sized
869 temporaries. However, sometimes we have a fixed upper limit on
870 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
871 instead. This is the case for Chill variable-sized strings. */
872 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
873 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
874 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
875 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
877 tmp = assign_stack_temp_for_type (mode, size, keep, type);
881 #ifndef PROMOTE_FOR_CALL_ONLY
883 mode = promote_mode (type, mode, &unsignedp, 0);
886 return gen_reg_rtx (mode);
889 /* Combine temporary stack slots which are adjacent on the stack.
891 This allows for better use of already allocated stack space. This is only
892 done for BLKmode slots because we can be sure that we won't have alignment
893 problems in this case. */
896 combine_temp_slots ()
898 struct temp_slot *p, *q;
899 struct temp_slot *prev_p, *prev_q;
902 /* We can't combine slots, because the information about which slot
903 is in which alias set will be lost. */
904 if (flag_strict_aliasing)
907 /* If there are a lot of temp slots, don't do anything unless
908 high levels of optimizaton. */
909 if (! flag_expensive_optimizations)
910 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
911 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
914 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
918 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
919 for (q = p->next, prev_q = p; q; q = prev_q->next)
922 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
924 if (p->base_offset + p->full_size == q->base_offset)
926 /* Q comes after P; combine Q into P. */
928 p->full_size += q->full_size;
931 else if (q->base_offset + q->full_size == p->base_offset)
933 /* P comes after Q; combine P into Q. */
935 q->full_size += p->full_size;
940 /* Either delete Q or advance past it. */
943 prev_q->next = q->next;
949 /* Either delete P or advance past it. */
953 prev_p->next = p->next;
955 temp_slots = p->next;
962 /* Find the temp slot corresponding to the object at address X. */
964 static struct temp_slot *
965 find_temp_slot_from_address (x)
971 for (p = temp_slots; p; p = p->next)
976 else if (XEXP (p->slot, 0) == x
978 || (GET_CODE (x) == PLUS
979 && XEXP (x, 0) == virtual_stack_vars_rtx
980 && GET_CODE (XEXP (x, 1)) == CONST_INT
981 && INTVAL (XEXP (x, 1)) >= p->base_offset
982 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
985 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
986 for (next = p->address; next; next = XEXP (next, 1))
987 if (XEXP (next, 0) == x)
991 /* If we have a sum involving a register, see if it points to a temp
993 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == REG
994 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
996 else if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == REG
997 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
1003 /* Indicate that NEW is an alternate way of referring to the temp slot
1004 that previously was known by OLD. */
1007 update_temp_slot_address (old, new)
1010 struct temp_slot *p;
1012 if (rtx_equal_p (old, new))
1015 p = find_temp_slot_from_address (old);
1017 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
1018 is a register, see if one operand of the PLUS is a temporary
1019 location. If so, NEW points into it. Otherwise, if both OLD and
1020 NEW are a PLUS and if there is a register in common between them.
1021 If so, try a recursive call on those values. */
1024 if (GET_CODE (old) != PLUS)
1027 if (GET_CODE (new) == REG)
1029 update_temp_slot_address (XEXP (old, 0), new);
1030 update_temp_slot_address (XEXP (old, 1), new);
1033 else if (GET_CODE (new) != PLUS)
1036 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
1037 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
1038 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
1039 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
1040 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
1041 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
1042 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
1043 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
1048 /* Otherwise add an alias for the temp's address. */
1049 else if (p->address == 0)
1053 if (GET_CODE (p->address) != EXPR_LIST)
1054 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1056 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1060 /* If X could be a reference to a temporary slot, mark the fact that its
1061 address was taken. */
1064 mark_temp_addr_taken (x)
1067 struct temp_slot *p;
1072 /* If X is not in memory or is at a constant address, it cannot be in
1073 a temporary slot. */
1074 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1077 p = find_temp_slot_from_address (XEXP (x, 0));
1082 /* If X could be a reference to a temporary slot, mark that slot as
1083 belonging to the to one level higher than the current level. If X
1084 matched one of our slots, just mark that one. Otherwise, we can't
1085 easily predict which it is, so upgrade all of them. Kept slots
1086 need not be touched.
1088 This is called when an ({...}) construct occurs and a statement
1089 returns a value in memory. */
1092 preserve_temp_slots (x)
1095 struct temp_slot *p = 0;
1097 /* If there is no result, we still might have some objects whose address
1098 were taken, so we need to make sure they stay around. */
1101 for (p = temp_slots; p; p = p->next)
1102 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1108 /* If X is a register that is being used as a pointer, see if we have
1109 a temporary slot we know it points to. To be consistent with
1110 the code below, we really should preserve all non-kept slots
1111 if we can't find a match, but that seems to be much too costly. */
1112 if (GET_CODE (x) == REG && REG_POINTER (x))
1113 p = find_temp_slot_from_address (x);
1115 /* If X is not in memory or is at a constant address, it cannot be in
1116 a temporary slot, but it can contain something whose address was
1118 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1120 for (p = temp_slots; p; p = p->next)
1121 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1127 /* First see if we can find a match. */
1129 p = find_temp_slot_from_address (XEXP (x, 0));
1133 /* Move everything at our level whose address was taken to our new
1134 level in case we used its address. */
1135 struct temp_slot *q;
1137 if (p->level == temp_slot_level)
1139 for (q = temp_slots; q; q = q->next)
1140 if (q != p && q->addr_taken && q->level == p->level)
1149 /* Otherwise, preserve all non-kept slots at this level. */
1150 for (p = temp_slots; p; p = p->next)
1151 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1155 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1156 with that RTL_EXPR, promote it into a temporary slot at the present
1157 level so it will not be freed when we free slots made in the
1161 preserve_rtl_expr_result (x)
1164 struct temp_slot *p;
1166 /* If X is not in memory or is at a constant address, it cannot be in
1167 a temporary slot. */
1168 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1171 /* If we can find a match, move it to our level unless it is already at
1173 p = find_temp_slot_from_address (XEXP (x, 0));
1176 p->level = MIN (p->level, temp_slot_level);
1183 /* Free all temporaries used so far. This is normally called at the end
1184 of generating code for a statement. Don't free any temporaries
1185 currently in use for an RTL_EXPR that hasn't yet been emitted.
1186 We could eventually do better than this since it can be reused while
1187 generating the same RTL_EXPR, but this is complex and probably not
1193 struct temp_slot *p;
1195 for (p = temp_slots; p; p = p->next)
1196 if (p->in_use && p->level == temp_slot_level && ! p->keep
1197 && p->rtl_expr == 0)
1200 combine_temp_slots ();
1203 /* Free all temporary slots used in T, an RTL_EXPR node. */
1206 free_temps_for_rtl_expr (t)
1209 struct temp_slot *p;
1211 for (p = temp_slots; p; p = p->next)
1212 if (p->rtl_expr == t)
1214 /* If this slot is below the current TEMP_SLOT_LEVEL, then it
1215 needs to be preserved. This can happen if a temporary in
1216 the RTL_EXPR was addressed; preserve_temp_slots will move
1217 the temporary into a higher level. */
1218 if (temp_slot_level <= p->level)
1221 p->rtl_expr = NULL_TREE;
1224 combine_temp_slots ();
1227 /* Mark all temporaries ever allocated in this function as not suitable
1228 for reuse until the current level is exited. */
1231 mark_all_temps_used ()
1233 struct temp_slot *p;
1235 for (p = temp_slots; p; p = p->next)
1237 p->in_use = p->keep = 1;
1238 p->level = MIN (p->level, temp_slot_level);
1242 /* Push deeper into the nesting level for stack temporaries. */
1250 /* Likewise, but save the new level as the place to allocate variables
1255 push_temp_slots_for_block ()
1259 var_temp_slot_level = temp_slot_level;
1262 /* Likewise, but save the new level as the place to allocate temporaries
1263 for TARGET_EXPRs. */
1266 push_temp_slots_for_target ()
1270 target_temp_slot_level = temp_slot_level;
1273 /* Set and get the value of target_temp_slot_level. The only
1274 permitted use of these functions is to save and restore this value. */
1277 get_target_temp_slot_level ()
1279 return target_temp_slot_level;
1283 set_target_temp_slot_level (level)
1286 target_temp_slot_level = level;
1290 /* Pop a temporary nesting level. All slots in use in the current level
1296 struct temp_slot *p;
1298 for (p = temp_slots; p; p = p->next)
1299 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1302 combine_temp_slots ();
1307 /* Initialize temporary slots. */
1312 /* We have not allocated any temporaries yet. */
1314 temp_slot_level = 0;
1315 var_temp_slot_level = 0;
1316 target_temp_slot_level = 0;
1319 /* Retroactively move an auto variable from a register to a stack slot.
1320 This is done when an address-reference to the variable is seen. */
1323 put_var_into_stack (decl)
1327 enum machine_mode promoted_mode, decl_mode;
1328 struct function *function = 0;
1330 int can_use_addressof;
1331 int volatilep = TREE_CODE (decl) != SAVE_EXPR && TREE_THIS_VOLATILE (decl);
1332 int usedp = (TREE_USED (decl)
1333 || (TREE_CODE (decl) != SAVE_EXPR && DECL_INITIAL (decl) != 0));
1335 context = decl_function_context (decl);
1337 /* Get the current rtl used for this object and its original mode. */
1338 reg = (TREE_CODE (decl) == SAVE_EXPR
1339 ? SAVE_EXPR_RTL (decl)
1340 : DECL_RTL_IF_SET (decl));
1342 /* No need to do anything if decl has no rtx yet
1343 since in that case caller is setting TREE_ADDRESSABLE
1344 and a stack slot will be assigned when the rtl is made. */
1348 /* Get the declared mode for this object. */
1349 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1350 : DECL_MODE (decl));
1351 /* Get the mode it's actually stored in. */
1352 promoted_mode = GET_MODE (reg);
1354 /* If this variable comes from an outer function,
1355 find that function's saved context. */
1356 if (context != current_function_decl && context != inline_function_decl)
1357 for (function = outer_function_chain; function; function = function->next)
1358 if (function->decl == context)
1361 /* If this is a variable-size object with a pseudo to address it,
1362 put that pseudo into the stack, if the var is nonlocal. */
1363 if (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl)
1364 && GET_CODE (reg) == MEM
1365 && GET_CODE (XEXP (reg, 0)) == REG
1366 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1368 reg = XEXP (reg, 0);
1369 decl_mode = promoted_mode = GET_MODE (reg);
1375 /* FIXME make it work for promoted modes too */
1376 && decl_mode == promoted_mode
1377 #ifdef NON_SAVING_SETJMP
1378 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1382 /* If we can't use ADDRESSOF, make sure we see through one we already
1384 if (! can_use_addressof && GET_CODE (reg) == MEM
1385 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1386 reg = XEXP (XEXP (reg, 0), 0);
1388 /* Now we should have a value that resides in one or more pseudo regs. */
1390 if (GET_CODE (reg) == REG)
1392 /* If this variable lives in the current function and we don't need
1393 to put things in the stack for the sake of setjmp, try to keep it
1394 in a register until we know we actually need the address. */
1395 if (can_use_addressof)
1396 gen_mem_addressof (reg, decl);
1398 put_reg_into_stack (function, reg, TREE_TYPE (decl), promoted_mode,
1399 decl_mode, volatilep, 0, usedp, 0);
1401 else if (GET_CODE (reg) == CONCAT)
1403 /* A CONCAT contains two pseudos; put them both in the stack.
1404 We do it so they end up consecutive.
1405 We fixup references to the parts only after we fixup references
1406 to the whole CONCAT, lest we do double fixups for the latter
1408 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1409 tree part_type = type_for_mode (part_mode, 0);
1410 rtx lopart = XEXP (reg, 0);
1411 rtx hipart = XEXP (reg, 1);
1412 #ifdef FRAME_GROWS_DOWNWARD
1413 /* Since part 0 should have a lower address, do it second. */
1414 put_reg_into_stack (function, hipart, part_type, part_mode,
1415 part_mode, volatilep, 0, 0, 0);
1416 put_reg_into_stack (function, lopart, part_type, part_mode,
1417 part_mode, volatilep, 0, 0, 0);
1419 put_reg_into_stack (function, lopart, part_type, part_mode,
1420 part_mode, volatilep, 0, 0, 0);
1421 put_reg_into_stack (function, hipart, part_type, part_mode,
1422 part_mode, volatilep, 0, 0, 0);
1425 /* Change the CONCAT into a combined MEM for both parts. */
1426 PUT_CODE (reg, MEM);
1427 set_mem_attributes (reg, decl, 1);
1429 /* The two parts are in memory order already.
1430 Use the lower parts address as ours. */
1431 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1432 /* Prevent sharing of rtl that might lose. */
1433 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1434 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1437 schedule_fixup_var_refs (function, reg, TREE_TYPE (decl),
1439 schedule_fixup_var_refs (function, lopart, part_type, part_mode, 0);
1440 schedule_fixup_var_refs (function, hipart, part_type, part_mode, 0);
1446 if (current_function_check_memory_usage)
1447 emit_library_call (chkr_set_right_libfunc, LCT_CONST_MAKE_BLOCK, VOIDmode,
1448 3, XEXP (reg, 0), Pmode,
1449 GEN_INT (GET_MODE_SIZE (GET_MODE (reg))),
1450 TYPE_MODE (sizetype),
1451 GEN_INT (MEMORY_USE_RW),
1452 TYPE_MODE (integer_type_node));
1455 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1456 into the stack frame of FUNCTION (0 means the current function).
1457 DECL_MODE is the machine mode of the user-level data type.
1458 PROMOTED_MODE is the machine mode of the register.
1459 VOLATILE_P is nonzero if this is for a "volatile" decl.
1460 USED_P is nonzero if this reg might have already been used in an insn. */
1463 put_reg_into_stack (function, reg, type, promoted_mode, decl_mode, volatile_p,
1464 original_regno, used_p, ht)
1465 struct function *function;
1468 enum machine_mode promoted_mode, decl_mode;
1470 unsigned int original_regno;
1472 struct hash_table *ht;
1474 struct function *func = function ? function : cfun;
1476 unsigned int regno = original_regno;
1479 regno = REGNO (reg);
1481 if (regno < func->x_max_parm_reg)
1482 new = func->x_parm_reg_stack_loc[regno];
1485 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode), 0, func);
1487 PUT_CODE (reg, MEM);
1488 PUT_MODE (reg, decl_mode);
1489 XEXP (reg, 0) = XEXP (new, 0);
1490 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1491 MEM_VOLATILE_P (reg) = volatile_p;
1493 /* If this is a memory ref that contains aggregate components,
1494 mark it as such for cse and loop optimize. If we are reusing a
1495 previously generated stack slot, then we need to copy the bit in
1496 case it was set for other reasons. For instance, it is set for
1497 __builtin_va_alist. */
1500 MEM_SET_IN_STRUCT_P (reg,
1501 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1502 MEM_ALIAS_SET (reg) = get_alias_set (type);
1505 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht);
1508 /* Make sure that all refs to the variable, previously made
1509 when it was a register, are fixed up to be valid again.
1510 See function above for meaning of arguments. */
1513 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht)
1514 struct function *function;
1517 enum machine_mode promoted_mode;
1518 struct hash_table *ht;
1520 int unsigned_p = type ? TREE_UNSIGNED (type) : 0;
1524 struct var_refs_queue *temp;
1527 = (struct var_refs_queue *) xmalloc (sizeof (struct var_refs_queue));
1528 temp->modified = reg;
1529 temp->promoted_mode = promoted_mode;
1530 temp->unsignedp = unsigned_p;
1531 temp->next = function->fixup_var_refs_queue;
1532 function->fixup_var_refs_queue = temp;
1535 /* Variable is local; fix it up now. */
1536 fixup_var_refs (reg, promoted_mode, unsigned_p, ht);
1540 fixup_var_refs (var, promoted_mode, unsignedp, ht)
1542 enum machine_mode promoted_mode;
1544 struct hash_table *ht;
1547 rtx first_insn = get_insns ();
1548 struct sequence_stack *stack = seq_stack;
1549 tree rtl_exps = rtl_expr_chain;
1551 /* If there's a hash table, it must record all uses of VAR. */
1556 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp);
1560 fixup_var_refs_insns (first_insn, var, promoted_mode, unsignedp,
1563 /* Scan all pending sequences too. */
1564 for (; stack; stack = stack->next)
1566 push_to_full_sequence (stack->first, stack->last);
1567 fixup_var_refs_insns (stack->first, var, promoted_mode, unsignedp,
1569 /* Update remembered end of sequence
1570 in case we added an insn at the end. */
1571 stack->last = get_last_insn ();
1575 /* Scan all waiting RTL_EXPRs too. */
1576 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1578 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1579 if (seq != const0_rtx && seq != 0)
1581 push_to_sequence (seq);
1582 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0);
1588 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1589 some part of an insn. Return a struct fixup_replacement whose OLD
1590 value is equal to X. Allocate a new structure if no such entry exists. */
1592 static struct fixup_replacement *
1593 find_fixup_replacement (replacements, x)
1594 struct fixup_replacement **replacements;
1597 struct fixup_replacement *p;
1599 /* See if we have already replaced this. */
1600 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1605 p = (struct fixup_replacement *) xmalloc (sizeof (struct fixup_replacement));
1608 p->next = *replacements;
1615 /* Scan the insn-chain starting with INSN for refs to VAR
1616 and fix them up. TOPLEVEL is nonzero if this chain is the
1617 main chain of insns for the current function. */
1620 fixup_var_refs_insns (insn, var, promoted_mode, unsignedp, toplevel)
1623 enum machine_mode promoted_mode;
1629 /* fixup_var_refs_insn might modify insn, so save its next
1631 rtx next = NEXT_INSN (insn);
1633 /* CALL_PLACEHOLDERs are special; we have to switch into each of
1634 the three sequences they (potentially) contain, and process
1635 them recursively. The CALL_INSN itself is not interesting. */
1637 if (GET_CODE (insn) == CALL_INSN
1638 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
1642 /* Look at the Normal call, sibling call and tail recursion
1643 sequences attached to the CALL_PLACEHOLDER. */
1644 for (i = 0; i < 3; i++)
1646 rtx seq = XEXP (PATTERN (insn), i);
1649 push_to_sequence (seq);
1650 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0);
1651 XEXP (PATTERN (insn), i) = get_insns ();
1657 else if (INSN_P (insn))
1658 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel);
1664 /* Look up the insns which reference VAR in HT and fix them up. Other
1665 arguments are the same as fixup_var_refs_insns.
1667 N.B. No need for special processing of CALL_PLACEHOLDERs here,
1668 because the hash table will point straight to the interesting insn
1669 (inside the CALL_PLACEHOLDER). */
1671 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp)
1672 struct hash_table *ht;
1674 enum machine_mode promoted_mode;
1677 struct insns_for_mem_entry *ime = (struct insns_for_mem_entry *)
1678 hash_lookup (ht, var, /*create=*/0, /*copy=*/0);
1679 rtx insn_list = ime->insns;
1683 rtx insn = XEXP (insn_list, 0);
1686 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, 1);
1688 insn_list = XEXP (insn_list, 1);
1693 /* Per-insn processing by fixup_var_refs_insns(_with_hash). INSN is
1694 the insn under examination, VAR is the variable to fix up
1695 references to, PROMOTED_MODE and UNSIGNEDP describe VAR, and
1696 TOPLEVEL is nonzero if this is the main insn chain for this
1699 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel)
1702 enum machine_mode promoted_mode;
1707 rtx set, prev, prev_set;
1710 /* Remember the notes in case we delete the insn. */
1711 note = REG_NOTES (insn);
1713 /* If this is a CLOBBER of VAR, delete it.
1715 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1716 and REG_RETVAL notes too. */
1717 if (GET_CODE (PATTERN (insn)) == CLOBBER
1718 && (XEXP (PATTERN (insn), 0) == var
1719 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1720 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1721 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1723 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1724 /* The REG_LIBCALL note will go away since we are going to
1725 turn INSN into a NOTE, so just delete the
1726 corresponding REG_RETVAL note. */
1727 remove_note (XEXP (note, 0),
1728 find_reg_note (XEXP (note, 0), REG_RETVAL,
1731 /* In unoptimized compilation, we shouldn't call delete_insn
1732 except in jump.c doing warnings. */
1733 PUT_CODE (insn, NOTE);
1734 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1735 NOTE_SOURCE_FILE (insn) = 0;
1738 /* The insn to load VAR from a home in the arglist
1739 is now a no-op. When we see it, just delete it.
1740 Similarly if this is storing VAR from a register from which
1741 it was loaded in the previous insn. This will occur
1742 when an ADDRESSOF was made for an arglist slot. */
1744 && (set = single_set (insn)) != 0
1745 && SET_DEST (set) == var
1746 /* If this represents the result of an insn group,
1747 don't delete the insn. */
1748 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1749 && (rtx_equal_p (SET_SRC (set), var)
1750 || (GET_CODE (SET_SRC (set)) == REG
1751 && (prev = prev_nonnote_insn (insn)) != 0
1752 && (prev_set = single_set (prev)) != 0
1753 && SET_DEST (prev_set) == SET_SRC (set)
1754 && rtx_equal_p (SET_SRC (prev_set), var))))
1756 /* In unoptimized compilation, we shouldn't call delete_insn
1757 except in jump.c doing warnings. */
1758 PUT_CODE (insn, NOTE);
1759 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1760 NOTE_SOURCE_FILE (insn) = 0;
1764 struct fixup_replacement *replacements = 0;
1765 rtx next_insn = NEXT_INSN (insn);
1767 if (SMALL_REGISTER_CLASSES)
1769 /* If the insn that copies the results of a CALL_INSN
1770 into a pseudo now references VAR, we have to use an
1771 intermediate pseudo since we want the life of the
1772 return value register to be only a single insn.
1774 If we don't use an intermediate pseudo, such things as
1775 address computations to make the address of VAR valid
1776 if it is not can be placed between the CALL_INSN and INSN.
1778 To make sure this doesn't happen, we record the destination
1779 of the CALL_INSN and see if the next insn uses both that
1782 if (call_dest != 0 && GET_CODE (insn) == INSN
1783 && reg_mentioned_p (var, PATTERN (insn))
1784 && reg_mentioned_p (call_dest, PATTERN (insn)))
1786 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1788 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1790 PATTERN (insn) = replace_rtx (PATTERN (insn),
1794 if (GET_CODE (insn) == CALL_INSN
1795 && GET_CODE (PATTERN (insn)) == SET)
1796 call_dest = SET_DEST (PATTERN (insn));
1797 else if (GET_CODE (insn) == CALL_INSN
1798 && GET_CODE (PATTERN (insn)) == PARALLEL
1799 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1800 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1805 /* See if we have to do anything to INSN now that VAR is in
1806 memory. If it needs to be loaded into a pseudo, use a single
1807 pseudo for the entire insn in case there is a MATCH_DUP
1808 between two operands. We pass a pointer to the head of
1809 a list of struct fixup_replacements. If fixup_var_refs_1
1810 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1811 it will record them in this list.
1813 If it allocated a pseudo for any replacement, we copy into
1816 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1819 /* If this is last_parm_insn, and any instructions were output
1820 after it to fix it up, then we must set last_parm_insn to
1821 the last such instruction emitted. */
1822 if (insn == last_parm_insn)
1823 last_parm_insn = PREV_INSN (next_insn);
1825 while (replacements)
1827 struct fixup_replacement *next;
1829 if (GET_CODE (replacements->new) == REG)
1834 /* OLD might be a (subreg (mem)). */
1835 if (GET_CODE (replacements->old) == SUBREG)
1837 = fixup_memory_subreg (replacements->old, insn, 0);
1840 = fixup_stack_1 (replacements->old, insn);
1842 insert_before = insn;
1844 /* If we are changing the mode, do a conversion.
1845 This might be wasteful, but combine.c will
1846 eliminate much of the waste. */
1848 if (GET_MODE (replacements->new)
1849 != GET_MODE (replacements->old))
1852 convert_move (replacements->new,
1853 replacements->old, unsignedp);
1854 seq = gen_sequence ();
1858 seq = gen_move_insn (replacements->new,
1861 emit_insn_before (seq, insert_before);
1864 next = replacements->next;
1865 free (replacements);
1866 replacements = next;
1870 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1871 But don't touch other insns referred to by reg-notes;
1872 we will get them elsewhere. */
1875 if (GET_CODE (note) != INSN_LIST)
1877 = walk_fixup_memory_subreg (XEXP (note, 0), insn, 1);
1878 note = XEXP (note, 1);
1882 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1883 See if the rtx expression at *LOC in INSN needs to be changed.
1885 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1886 contain a list of original rtx's and replacements. If we find that we need
1887 to modify this insn by replacing a memory reference with a pseudo or by
1888 making a new MEM to implement a SUBREG, we consult that list to see if
1889 we have already chosen a replacement. If none has already been allocated,
1890 we allocate it and update the list. fixup_var_refs_insn will copy VAR
1891 or the SUBREG, as appropriate, to the pseudo. */
1894 fixup_var_refs_1 (var, promoted_mode, loc, insn, replacements)
1896 enum machine_mode promoted_mode;
1899 struct fixup_replacement **replacements;
1902 register rtx x = *loc;
1903 RTX_CODE code = GET_CODE (x);
1904 register const char *fmt;
1905 register rtx tem, tem1;
1906 struct fixup_replacement *replacement;
1911 if (XEXP (x, 0) == var)
1913 /* Prevent sharing of rtl that might lose. */
1914 rtx sub = copy_rtx (XEXP (var, 0));
1916 if (! validate_change (insn, loc, sub, 0))
1918 rtx y = gen_reg_rtx (GET_MODE (sub));
1921 /* We should be able to replace with a register or all is lost.
1922 Note that we can't use validate_change to verify this, since
1923 we're not caring for replacing all dups simultaneously. */
1924 if (! validate_replace_rtx (*loc, y, insn))
1927 /* Careful! First try to recognize a direct move of the
1928 value, mimicking how things are done in gen_reload wrt
1929 PLUS. Consider what happens when insn is a conditional
1930 move instruction and addsi3 clobbers flags. */
1933 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1934 seq = gen_sequence ();
1937 if (recog_memoized (new_insn) < 0)
1939 /* That failed. Fall back on force_operand and hope. */
1942 sub = force_operand (sub, y);
1944 emit_insn (gen_move_insn (y, sub));
1945 seq = gen_sequence ();
1950 /* Don't separate setter from user. */
1951 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1952 insn = PREV_INSN (insn);
1955 emit_insn_before (seq, insn);
1963 /* If we already have a replacement, use it. Otherwise,
1964 try to fix up this address in case it is invalid. */
1966 replacement = find_fixup_replacement (replacements, var);
1967 if (replacement->new)
1969 *loc = replacement->new;
1973 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1975 /* Unless we are forcing memory to register or we changed the mode,
1976 we can leave things the way they are if the insn is valid. */
1978 INSN_CODE (insn) = -1;
1979 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1980 && recog_memoized (insn) >= 0)
1983 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1987 /* If X contains VAR, we need to unshare it here so that we update
1988 each occurrence separately. But all identical MEMs in one insn
1989 must be replaced with the same rtx because of the possibility of
1992 if (reg_mentioned_p (var, x))
1994 replacement = find_fixup_replacement (replacements, x);
1995 if (replacement->new == 0)
1996 replacement->new = copy_most_rtx (x, var);
1998 *loc = x = replacement->new;
1999 code = GET_CODE (x);
2015 /* Note that in some cases those types of expressions are altered
2016 by optimize_bit_field, and do not survive to get here. */
2017 if (XEXP (x, 0) == var
2018 || (GET_CODE (XEXP (x, 0)) == SUBREG
2019 && SUBREG_REG (XEXP (x, 0)) == var))
2021 /* Get TEM as a valid MEM in the mode presently in the insn.
2023 We don't worry about the possibility of MATCH_DUP here; it
2024 is highly unlikely and would be tricky to handle. */
2027 if (GET_CODE (tem) == SUBREG)
2029 if (GET_MODE_BITSIZE (GET_MODE (tem))
2030 > GET_MODE_BITSIZE (GET_MODE (var)))
2032 replacement = find_fixup_replacement (replacements, var);
2033 if (replacement->new == 0)
2034 replacement->new = gen_reg_rtx (GET_MODE (var));
2035 SUBREG_REG (tem) = replacement->new;
2037 /* The following code works only if we have a MEM, so we
2038 need to handle the subreg here. We directly substitute
2039 it assuming that a subreg must be OK here. We already
2040 scheduled a replacement to copy the mem into the
2046 tem = fixup_memory_subreg (tem, insn, 0);
2049 tem = fixup_stack_1 (tem, insn);
2051 /* Unless we want to load from memory, get TEM into the proper mode
2052 for an extract from memory. This can only be done if the
2053 extract is at a constant position and length. */
2055 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
2056 && GET_CODE (XEXP (x, 2)) == CONST_INT
2057 && ! mode_dependent_address_p (XEXP (tem, 0))
2058 && ! MEM_VOLATILE_P (tem))
2060 enum machine_mode wanted_mode = VOIDmode;
2061 enum machine_mode is_mode = GET_MODE (tem);
2062 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
2065 if (GET_CODE (x) == ZERO_EXTRACT)
2068 = insn_data[(int) CODE_FOR_extzv].operand[1].mode;
2069 if (wanted_mode == VOIDmode)
2070 wanted_mode = word_mode;
2074 if (GET_CODE (x) == SIGN_EXTRACT)
2076 wanted_mode = insn_data[(int) CODE_FOR_extv].operand[1].mode;
2077 if (wanted_mode == VOIDmode)
2078 wanted_mode = word_mode;
2081 /* If we have a narrower mode, we can do something. */
2082 if (wanted_mode != VOIDmode
2083 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2085 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2086 rtx old_pos = XEXP (x, 2);
2089 /* If the bytes and bits are counted differently, we
2090 must adjust the offset. */
2091 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2092 offset = (GET_MODE_SIZE (is_mode)
2093 - GET_MODE_SIZE (wanted_mode) - offset);
2095 pos %= GET_MODE_BITSIZE (wanted_mode);
2097 newmem = gen_rtx_MEM (wanted_mode,
2098 plus_constant (XEXP (tem, 0), offset));
2099 MEM_COPY_ATTRIBUTES (newmem, tem);
2101 /* Make the change and see if the insn remains valid. */
2102 INSN_CODE (insn) = -1;
2103 XEXP (x, 0) = newmem;
2104 XEXP (x, 2) = GEN_INT (pos);
2106 if (recog_memoized (insn) >= 0)
2109 /* Otherwise, restore old position. XEXP (x, 0) will be
2111 XEXP (x, 2) = old_pos;
2115 /* If we get here, the bitfield extract insn can't accept a memory
2116 reference. Copy the input into a register. */
2118 tem1 = gen_reg_rtx (GET_MODE (tem));
2119 emit_insn_before (gen_move_insn (tem1, tem), insn);
2126 if (SUBREG_REG (x) == var)
2128 /* If this is a special SUBREG made because VAR was promoted
2129 from a wider mode, replace it with VAR and call ourself
2130 recursively, this time saying that the object previously
2131 had its current mode (by virtue of the SUBREG). */
2133 if (SUBREG_PROMOTED_VAR_P (x))
2136 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements);
2140 /* If this SUBREG makes VAR wider, it has become a paradoxical
2141 SUBREG with VAR in memory, but these aren't allowed at this
2142 stage of the compilation. So load VAR into a pseudo and take
2143 a SUBREG of that pseudo. */
2144 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2146 replacement = find_fixup_replacement (replacements, var);
2147 if (replacement->new == 0)
2148 replacement->new = gen_reg_rtx (promoted_mode);
2149 SUBREG_REG (x) = replacement->new;
2153 /* See if we have already found a replacement for this SUBREG.
2154 If so, use it. Otherwise, make a MEM and see if the insn
2155 is recognized. If not, or if we should force MEM into a register,
2156 make a pseudo for this SUBREG. */
2157 replacement = find_fixup_replacement (replacements, x);
2158 if (replacement->new)
2160 *loc = replacement->new;
2164 replacement->new = *loc = fixup_memory_subreg (x, insn, 0);
2166 INSN_CODE (insn) = -1;
2167 if (! flag_force_mem && recog_memoized (insn) >= 0)
2170 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2176 /* First do special simplification of bit-field references. */
2177 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2178 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2179 optimize_bit_field (x, insn, 0);
2180 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2181 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2182 optimize_bit_field (x, insn, 0);
2184 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2185 into a register and then store it back out. */
2186 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2187 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2188 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2189 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2190 > GET_MODE_SIZE (GET_MODE (var))))
2192 replacement = find_fixup_replacement (replacements, var);
2193 if (replacement->new == 0)
2194 replacement->new = gen_reg_rtx (GET_MODE (var));
2196 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2197 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2200 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2201 insn into a pseudo and store the low part of the pseudo into VAR. */
2202 if (GET_CODE (SET_DEST (x)) == SUBREG
2203 && SUBREG_REG (SET_DEST (x)) == var
2204 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2205 > GET_MODE_SIZE (GET_MODE (var))))
2207 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2208 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2215 rtx dest = SET_DEST (x);
2216 rtx src = SET_SRC (x);
2218 rtx outerdest = dest;
2221 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2222 || GET_CODE (dest) == SIGN_EXTRACT
2223 || GET_CODE (dest) == ZERO_EXTRACT)
2224 dest = XEXP (dest, 0);
2226 if (GET_CODE (src) == SUBREG)
2227 src = SUBREG_REG (src);
2229 /* If VAR does not appear at the top level of the SET
2230 just scan the lower levels of the tree. */
2232 if (src != var && dest != var)
2235 /* We will need to rerecognize this insn. */
2236 INSN_CODE (insn) = -1;
2239 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var)
2241 /* Since this case will return, ensure we fixup all the
2243 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2244 insn, replacements);
2245 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2246 insn, replacements);
2247 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2248 insn, replacements);
2250 tem = XEXP (outerdest, 0);
2252 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2253 that may appear inside a ZERO_EXTRACT.
2254 This was legitimate when the MEM was a REG. */
2255 if (GET_CODE (tem) == SUBREG
2256 && SUBREG_REG (tem) == var)
2257 tem = fixup_memory_subreg (tem, insn, 0);
2259 tem = fixup_stack_1 (tem, insn);
2261 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2262 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2263 && ! mode_dependent_address_p (XEXP (tem, 0))
2264 && ! MEM_VOLATILE_P (tem))
2266 enum machine_mode wanted_mode;
2267 enum machine_mode is_mode = GET_MODE (tem);
2268 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2270 wanted_mode = insn_data[(int) CODE_FOR_insv].operand[0].mode;
2271 if (wanted_mode == VOIDmode)
2272 wanted_mode = word_mode;
2274 /* If we have a narrower mode, we can do something. */
2275 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2277 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2278 rtx old_pos = XEXP (outerdest, 2);
2281 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2282 offset = (GET_MODE_SIZE (is_mode)
2283 - GET_MODE_SIZE (wanted_mode) - offset);
2285 pos %= GET_MODE_BITSIZE (wanted_mode);
2287 newmem = gen_rtx_MEM (wanted_mode,
2288 plus_constant (XEXP (tem, 0),
2290 MEM_COPY_ATTRIBUTES (newmem, tem);
2292 /* Make the change and see if the insn remains valid. */
2293 INSN_CODE (insn) = -1;
2294 XEXP (outerdest, 0) = newmem;
2295 XEXP (outerdest, 2) = GEN_INT (pos);
2297 if (recog_memoized (insn) >= 0)
2300 /* Otherwise, restore old position. XEXP (x, 0) will be
2302 XEXP (outerdest, 2) = old_pos;
2306 /* If we get here, the bit-field store doesn't allow memory
2307 or isn't located at a constant position. Load the value into
2308 a register, do the store, and put it back into memory. */
2310 tem1 = gen_reg_rtx (GET_MODE (tem));
2311 emit_insn_before (gen_move_insn (tem1, tem), insn);
2312 emit_insn_after (gen_move_insn (tem, tem1), insn);
2313 XEXP (outerdest, 0) = tem1;
2318 /* STRICT_LOW_PART is a no-op on memory references
2319 and it can cause combinations to be unrecognizable,
2322 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2323 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2325 /* A valid insn to copy VAR into or out of a register
2326 must be left alone, to avoid an infinite loop here.
2327 If the reference to VAR is by a subreg, fix that up,
2328 since SUBREG is not valid for a memref.
2329 Also fix up the address of the stack slot.
2331 Note that we must not try to recognize the insn until
2332 after we know that we have valid addresses and no
2333 (subreg (mem ...) ...) constructs, since these interfere
2334 with determining the validity of the insn. */
2336 if ((SET_SRC (x) == var
2337 || (GET_CODE (SET_SRC (x)) == SUBREG
2338 && SUBREG_REG (SET_SRC (x)) == var))
2339 && (GET_CODE (SET_DEST (x)) == REG
2340 || (GET_CODE (SET_DEST (x)) == SUBREG
2341 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2342 && GET_MODE (var) == promoted_mode
2343 && x == single_set (insn))
2347 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2348 if (replacement->new)
2349 SET_SRC (x) = replacement->new;
2350 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2351 SET_SRC (x) = replacement->new
2352 = fixup_memory_subreg (SET_SRC (x), insn, 0);
2354 SET_SRC (x) = replacement->new
2355 = fixup_stack_1 (SET_SRC (x), insn);
2357 if (recog_memoized (insn) >= 0)
2360 /* INSN is not valid, but we know that we want to
2361 copy SET_SRC (x) to SET_DEST (x) in some way. So
2362 we generate the move and see whether it requires more
2363 than one insn. If it does, we emit those insns and
2364 delete INSN. Otherwise, we an just replace the pattern
2365 of INSN; we have already verified above that INSN has
2366 no other function that to do X. */
2368 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2369 if (GET_CODE (pat) == SEQUENCE)
2371 last = emit_insn_before (pat, insn);
2373 /* INSN might have REG_RETVAL or other important notes, so
2374 we need to store the pattern of the last insn in the
2375 sequence into INSN similarly to the normal case. LAST
2376 should not have REG_NOTES, but we allow them if INSN has
2378 if (REG_NOTES (last) && REG_NOTES (insn))
2380 if (REG_NOTES (last))
2381 REG_NOTES (insn) = REG_NOTES (last);
2382 PATTERN (insn) = PATTERN (last);
2384 PUT_CODE (last, NOTE);
2385 NOTE_LINE_NUMBER (last) = NOTE_INSN_DELETED;
2386 NOTE_SOURCE_FILE (last) = 0;
2389 PATTERN (insn) = pat;
2394 if ((SET_DEST (x) == var
2395 || (GET_CODE (SET_DEST (x)) == SUBREG
2396 && SUBREG_REG (SET_DEST (x)) == var))
2397 && (GET_CODE (SET_SRC (x)) == REG
2398 || (GET_CODE (SET_SRC (x)) == SUBREG
2399 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2400 && GET_MODE (var) == promoted_mode
2401 && x == single_set (insn))
2405 if (GET_CODE (SET_DEST (x)) == SUBREG)
2406 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn, 0);
2408 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2410 if (recog_memoized (insn) >= 0)
2413 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2414 if (GET_CODE (pat) == SEQUENCE)
2416 last = emit_insn_before (pat, insn);
2418 /* INSN might have REG_RETVAL or other important notes, so
2419 we need to store the pattern of the last insn in the
2420 sequence into INSN similarly to the normal case. LAST
2421 should not have REG_NOTES, but we allow them if INSN has
2423 if (REG_NOTES (last) && REG_NOTES (insn))
2425 if (REG_NOTES (last))
2426 REG_NOTES (insn) = REG_NOTES (last);
2427 PATTERN (insn) = PATTERN (last);
2429 PUT_CODE (last, NOTE);
2430 NOTE_LINE_NUMBER (last) = NOTE_INSN_DELETED;
2431 NOTE_SOURCE_FILE (last) = 0;
2434 PATTERN (insn) = pat;
2439 /* Otherwise, storing into VAR must be handled specially
2440 by storing into a temporary and copying that into VAR
2441 with a new insn after this one. Note that this case
2442 will be used when storing into a promoted scalar since
2443 the insn will now have different modes on the input
2444 and output and hence will be invalid (except for the case
2445 of setting it to a constant, which does not need any
2446 change if it is valid). We generate extra code in that case,
2447 but combine.c will eliminate it. */
2452 rtx fixeddest = SET_DEST (x);
2454 /* STRICT_LOW_PART can be discarded, around a MEM. */
2455 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2456 fixeddest = XEXP (fixeddest, 0);
2457 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2458 if (GET_CODE (fixeddest) == SUBREG)
2460 fixeddest = fixup_memory_subreg (fixeddest, insn, 0);
2461 promoted_mode = GET_MODE (fixeddest);
2464 fixeddest = fixup_stack_1 (fixeddest, insn);
2466 temp = gen_reg_rtx (promoted_mode);
2468 emit_insn_after (gen_move_insn (fixeddest,
2469 gen_lowpart (GET_MODE (fixeddest),
2473 SET_DEST (x) = temp;
2481 /* Nothing special about this RTX; fix its operands. */
2483 fmt = GET_RTX_FORMAT (code);
2484 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2487 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements);
2488 else if (fmt[i] == 'E')
2491 for (j = 0; j < XVECLEN (x, i); j++)
2492 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2493 insn, replacements);
2498 /* Given X, an rtx of the form (SUBREG:m1 (MEM:m2 addr)),
2499 return an rtx (MEM:m1 newaddr) which is equivalent.
2500 If any insns must be emitted to compute NEWADDR, put them before INSN.
2502 UNCRITICAL nonzero means accept paradoxical subregs.
2503 This is used for subregs found inside REG_NOTES. */
2506 fixup_memory_subreg (x, insn, uncritical)
2511 int offset = SUBREG_BYTE (x);
2512 rtx addr = XEXP (SUBREG_REG (x), 0);
2513 enum machine_mode mode = GET_MODE (x);
2516 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2517 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))
2521 if (!flag_force_addr
2522 && memory_address_p (mode, plus_constant (addr, offset)))
2523 /* Shortcut if no insns need be emitted. */
2524 return adjust_address (SUBREG_REG (x), mode, offset);
2527 result = adjust_address (SUBREG_REG (x), mode, offset);
2528 emit_insn_before (gen_sequence (), insn);
2533 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2534 Replace subexpressions of X in place.
2535 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2536 Otherwise return X, with its contents possibly altered.
2538 If any insns must be emitted to compute NEWADDR, put them before INSN.
2540 UNCRITICAL is as in fixup_memory_subreg. */
2543 walk_fixup_memory_subreg (x, insn, uncritical)
2548 register enum rtx_code code;
2549 register const char *fmt;
2555 code = GET_CODE (x);
2557 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2558 return fixup_memory_subreg (x, insn, uncritical);
2560 /* Nothing special about this RTX; fix its operands. */
2562 fmt = GET_RTX_FORMAT (code);
2563 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2566 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn, uncritical);
2567 else if (fmt[i] == 'E')
2570 for (j = 0; j < XVECLEN (x, i); j++)
2572 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn, uncritical);
2578 /* For each memory ref within X, if it refers to a stack slot
2579 with an out of range displacement, put the address in a temp register
2580 (emitting new insns before INSN to load these registers)
2581 and alter the memory ref to use that register.
2582 Replace each such MEM rtx with a copy, to avoid clobberage. */
2585 fixup_stack_1 (x, insn)
2590 register RTX_CODE code = GET_CODE (x);
2591 register const char *fmt;
2595 register rtx ad = XEXP (x, 0);
2596 /* If we have address of a stack slot but it's not valid
2597 (displacement is too large), compute the sum in a register. */
2598 if (GET_CODE (ad) == PLUS
2599 && GET_CODE (XEXP (ad, 0)) == REG
2600 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2601 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2602 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2603 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2604 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2606 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2607 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2608 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2609 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2612 if (memory_address_p (GET_MODE (x), ad))
2616 temp = copy_to_reg (ad);
2617 seq = gen_sequence ();
2619 emit_insn_before (seq, insn);
2620 return replace_equiv_address (x, temp);
2625 fmt = GET_RTX_FORMAT (code);
2626 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2629 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2630 else if (fmt[i] == 'E')
2633 for (j = 0; j < XVECLEN (x, i); j++)
2634 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2640 /* Optimization: a bit-field instruction whose field
2641 happens to be a byte or halfword in memory
2642 can be changed to a move instruction.
2644 We call here when INSN is an insn to examine or store into a bit-field.
2645 BODY is the SET-rtx to be altered.
2647 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2648 (Currently this is called only from function.c, and EQUIV_MEM
2652 optimize_bit_field (body, insn, equiv_mem)
2657 register rtx bitfield;
2660 enum machine_mode mode;
2662 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2663 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2664 bitfield = SET_DEST (body), destflag = 1;
2666 bitfield = SET_SRC (body), destflag = 0;
2668 /* First check that the field being stored has constant size and position
2669 and is in fact a byte or halfword suitably aligned. */
2671 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2672 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2673 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2675 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2677 register rtx memref = 0;
2679 /* Now check that the containing word is memory, not a register,
2680 and that it is safe to change the machine mode. */
2682 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2683 memref = XEXP (bitfield, 0);
2684 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2686 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2687 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2688 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2689 memref = SUBREG_REG (XEXP (bitfield, 0));
2690 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2692 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2693 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2696 && ! mode_dependent_address_p (XEXP (memref, 0))
2697 && ! MEM_VOLATILE_P (memref))
2699 /* Now adjust the address, first for any subreg'ing
2700 that we are now getting rid of,
2701 and then for which byte of the word is wanted. */
2703 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2706 /* Adjust OFFSET to count bits from low-address byte. */
2707 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2708 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2709 - offset - INTVAL (XEXP (bitfield, 1)));
2711 /* Adjust OFFSET to count bytes from low-address byte. */
2712 offset /= BITS_PER_UNIT;
2713 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2715 offset += (SUBREG_BYTE (XEXP (bitfield, 0))
2716 / UNITS_PER_WORD) * UNITS_PER_WORD;
2717 if (BYTES_BIG_ENDIAN)
2718 offset -= (MIN (UNITS_PER_WORD,
2719 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2720 - MIN (UNITS_PER_WORD,
2721 GET_MODE_SIZE (GET_MODE (memref))));
2725 memref = adjust_address (memref, mode, offset);
2726 insns = get_insns ();
2728 emit_insns_before (insns, insn);
2730 /* Store this memory reference where
2731 we found the bit field reference. */
2735 validate_change (insn, &SET_DEST (body), memref, 1);
2736 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2738 rtx src = SET_SRC (body);
2739 while (GET_CODE (src) == SUBREG
2740 && SUBREG_BYTE (src) == 0)
2741 src = SUBREG_REG (src);
2742 if (GET_MODE (src) != GET_MODE (memref))
2743 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2744 validate_change (insn, &SET_SRC (body), src, 1);
2746 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2747 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2748 /* This shouldn't happen because anything that didn't have
2749 one of these modes should have got converted explicitly
2750 and then referenced through a subreg.
2751 This is so because the original bit-field was
2752 handled by agg_mode and so its tree structure had
2753 the same mode that memref now has. */
2758 rtx dest = SET_DEST (body);
2760 while (GET_CODE (dest) == SUBREG
2761 && SUBREG_BYTE (dest) == 0
2762 && (GET_MODE_CLASS (GET_MODE (dest))
2763 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2764 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2766 dest = SUBREG_REG (dest);
2768 validate_change (insn, &SET_DEST (body), dest, 1);
2770 if (GET_MODE (dest) == GET_MODE (memref))
2771 validate_change (insn, &SET_SRC (body), memref, 1);
2774 /* Convert the mem ref to the destination mode. */
2775 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2778 convert_move (newreg, memref,
2779 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2783 validate_change (insn, &SET_SRC (body), newreg, 1);
2787 /* See if we can convert this extraction or insertion into
2788 a simple move insn. We might not be able to do so if this
2789 was, for example, part of a PARALLEL.
2791 If we succeed, write out any needed conversions. If we fail,
2792 it is hard to guess why we failed, so don't do anything
2793 special; just let the optimization be suppressed. */
2795 if (apply_change_group () && seq)
2796 emit_insns_before (seq, insn);
2801 /* These routines are responsible for converting virtual register references
2802 to the actual hard register references once RTL generation is complete.
2804 The following four variables are used for communication between the
2805 routines. They contain the offsets of the virtual registers from their
2806 respective hard registers. */
2808 static int in_arg_offset;
2809 static int var_offset;
2810 static int dynamic_offset;
2811 static int out_arg_offset;
2812 static int cfa_offset;
2814 /* In most machines, the stack pointer register is equivalent to the bottom
2817 #ifndef STACK_POINTER_OFFSET
2818 #define STACK_POINTER_OFFSET 0
2821 /* If not defined, pick an appropriate default for the offset of dynamically
2822 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2823 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2825 #ifndef STACK_DYNAMIC_OFFSET
2827 /* The bottom of the stack points to the actual arguments. If
2828 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2829 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2830 stack space for register parameters is not pushed by the caller, but
2831 rather part of the fixed stack areas and hence not included in
2832 `current_function_outgoing_args_size'. Nevertheless, we must allow
2833 for it when allocating stack dynamic objects. */
2835 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2836 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2837 ((ACCUMULATE_OUTGOING_ARGS \
2838 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2839 + (STACK_POINTER_OFFSET)) \
2842 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2843 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2844 + (STACK_POINTER_OFFSET))
2848 /* On most machines, the CFA coincides with the first incoming parm. */
2850 #ifndef ARG_POINTER_CFA_OFFSET
2851 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2854 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just had
2855 its address taken. DECL is the decl for the object stored in the
2856 register, for later use if we do need to force REG into the stack.
2857 REG is overwritten by the MEM like in put_reg_into_stack. */
2860 gen_mem_addressof (reg, decl)
2864 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2867 /* If the original REG was a user-variable, then so is the REG whose
2868 address is being taken. Likewise for unchanging. */
2869 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2870 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2872 PUT_CODE (reg, MEM);
2876 tree type = TREE_TYPE (decl);
2877 enum machine_mode decl_mode
2878 = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
2879 : DECL_MODE (decl));
2881 PUT_MODE (reg, decl_mode);
2882 MEM_VOLATILE_P (reg) = TREE_SIDE_EFFECTS (decl);
2883 MEM_SET_IN_STRUCT_P (reg, AGGREGATE_TYPE_P (type));
2884 MEM_ALIAS_SET (reg) = get_alias_set (decl);
2886 if (TREE_USED (decl) || DECL_INITIAL (decl) != 0)
2887 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), 0);
2891 /* We have no alias information about this newly created MEM. */
2892 MEM_ALIAS_SET (reg) = 0;
2894 fixup_var_refs (reg, GET_MODE (reg), 0, 0);
2900 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2903 flush_addressof (decl)
2906 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2907 && DECL_RTL (decl) != 0
2908 && GET_CODE (DECL_RTL (decl)) == MEM
2909 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2910 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2911 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2914 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2917 put_addressof_into_stack (r, ht)
2919 struct hash_table *ht;
2922 int volatile_p, used_p;
2924 rtx reg = XEXP (r, 0);
2926 if (GET_CODE (reg) != REG)
2929 decl = ADDRESSOF_DECL (r);
2932 type = TREE_TYPE (decl);
2933 volatile_p = (TREE_CODE (decl) != SAVE_EXPR
2934 && TREE_THIS_VOLATILE (decl));
2935 used_p = (TREE_USED (decl)
2936 || (TREE_CODE (decl) != SAVE_EXPR
2937 && DECL_INITIAL (decl) != 0));
2946 put_reg_into_stack (0, reg, type, GET_MODE (reg), GET_MODE (reg),
2947 volatile_p, ADDRESSOF_REGNO (r), used_p, ht);
2950 /* List of replacements made below in purge_addressof_1 when creating
2951 bitfield insertions. */
2952 static rtx purge_bitfield_addressof_replacements;
2954 /* List of replacements made below in purge_addressof_1 for patterns
2955 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2956 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2957 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2958 enough in complex cases, e.g. when some field values can be
2959 extracted by usage MEM with narrower mode. */
2960 static rtx purge_addressof_replacements;
2962 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2963 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2964 the stack. If the function returns FALSE then the replacement could not
2968 purge_addressof_1 (loc, insn, force, store, ht)
2972 struct hash_table *ht;
2980 /* Re-start here to avoid recursion in common cases. */
2987 code = GET_CODE (x);
2989 /* If we don't return in any of the cases below, we will recurse inside
2990 the RTX, which will normally result in any ADDRESSOF being forced into
2994 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1, ht);
2995 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0, ht);
2998 else if (code == ADDRESSOF)
3002 if (GET_CODE (XEXP (x, 0)) != MEM)
3004 put_addressof_into_stack (x, ht);
3008 /* We must create a copy of the rtx because it was created by
3009 overwriting a REG rtx which is always shared. */
3010 sub = copy_rtx (XEXP (XEXP (x, 0), 0));
3011 if (validate_change (insn, loc, sub, 0)
3012 || validate_replace_rtx (x, sub, insn))
3016 sub = force_operand (sub, NULL_RTX);
3017 if (! validate_change (insn, loc, sub, 0)
3018 && ! validate_replace_rtx (x, sub, insn))
3021 insns = gen_sequence ();
3023 emit_insn_before (insns, insn);
3027 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
3029 rtx sub = XEXP (XEXP (x, 0), 0);
3032 if (GET_CODE (sub) == MEM)
3034 sub2 = gen_rtx_MEM (GET_MODE (x), copy_rtx (XEXP (sub, 0)));
3035 MEM_COPY_ATTRIBUTES (sub2, sub);
3038 else if (GET_CODE (sub) == REG
3039 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
3041 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
3043 int size_x, size_sub;
3047 /* When processing REG_NOTES look at the list of
3048 replacements done on the insn to find the register that X
3052 for (tem = purge_bitfield_addressof_replacements;
3054 tem = XEXP (XEXP (tem, 1), 1))
3055 if (rtx_equal_p (x, XEXP (tem, 0)))
3057 *loc = XEXP (XEXP (tem, 1), 0);
3061 /* See comment for purge_addressof_replacements. */
3062 for (tem = purge_addressof_replacements;
3064 tem = XEXP (XEXP (tem, 1), 1))
3065 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3067 rtx z = XEXP (XEXP (tem, 1), 0);
3069 if (GET_MODE (x) == GET_MODE (z)
3070 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
3071 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
3074 /* It can happen that the note may speak of things
3075 in a wider (or just different) mode than the
3076 code did. This is especially true of
3079 if (GET_CODE (z) == SUBREG && SUBREG_BYTE (z) == 0)
3082 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3083 && (GET_MODE_SIZE (GET_MODE (x))
3084 > GET_MODE_SIZE (GET_MODE (z))))
3086 /* This can occur as a result in invalid
3087 pointer casts, e.g. float f; ...
3088 *(long long int *)&f.
3089 ??? We could emit a warning here, but
3090 without a line number that wouldn't be
3092 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
3095 z = gen_lowpart (GET_MODE (x), z);
3101 /* Sometimes we may not be able to find the replacement. For
3102 example when the original insn was a MEM in a wider mode,
3103 and the note is part of a sign extension of a narrowed
3104 version of that MEM. Gcc testcase compile/990829-1.c can
3105 generate an example of this siutation. Rather than complain
3106 we return false, which will prompt our caller to remove the
3111 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3112 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3114 /* Don't even consider working with paradoxical subregs,
3115 or the moral equivalent seen here. */
3116 if (size_x <= size_sub
3117 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3119 /* Do a bitfield insertion to mirror what would happen
3126 rtx p = PREV_INSN (insn);
3129 val = gen_reg_rtx (GET_MODE (x));
3130 if (! validate_change (insn, loc, val, 0))
3132 /* Discard the current sequence and put the
3133 ADDRESSOF on stack. */
3137 seq = gen_sequence ();
3139 emit_insn_before (seq, insn);
3140 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3144 store_bit_field (sub, size_x, 0, GET_MODE (x),
3145 val, GET_MODE_SIZE (GET_MODE (sub)),
3146 GET_MODE_ALIGNMENT (GET_MODE (sub)));
3148 /* Make sure to unshare any shared rtl that store_bit_field
3149 might have created. */
3150 unshare_all_rtl_again (get_insns ());
3152 seq = gen_sequence ();
3154 p = emit_insn_after (seq, insn);
3155 if (NEXT_INSN (insn))
3156 compute_insns_for_mem (NEXT_INSN (insn),
3157 p ? NEXT_INSN (p) : NULL_RTX,
3162 rtx p = PREV_INSN (insn);
3165 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3166 GET_MODE (x), GET_MODE (x),
3167 GET_MODE_SIZE (GET_MODE (sub)),
3168 GET_MODE_SIZE (GET_MODE (sub)));
3170 if (! validate_change (insn, loc, val, 0))
3172 /* Discard the current sequence and put the
3173 ADDRESSOF on stack. */
3178 seq = gen_sequence ();
3180 emit_insn_before (seq, insn);
3181 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3185 /* Remember the replacement so that the same one can be done
3186 on the REG_NOTES. */
3187 purge_bitfield_addressof_replacements
3188 = gen_rtx_EXPR_LIST (VOIDmode, x,
3191 purge_bitfield_addressof_replacements));
3193 /* We replaced with a reg -- all done. */
3198 else if (validate_change (insn, loc, sub, 0))
3200 /* Remember the replacement so that the same one can be done
3201 on the REG_NOTES. */
3202 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3206 for (tem = purge_addressof_replacements;
3208 tem = XEXP (XEXP (tem, 1), 1))
3209 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3211 XEXP (XEXP (tem, 1), 0) = sub;
3214 purge_addressof_replacements
3215 = gen_rtx (EXPR_LIST, VOIDmode, XEXP (x, 0),
3216 gen_rtx_EXPR_LIST (VOIDmode, sub,
3217 purge_addressof_replacements));
3225 /* Scan all subexpressions. */
3226 fmt = GET_RTX_FORMAT (code);
3227 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3230 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0, ht);
3231 else if (*fmt == 'E')
3232 for (j = 0; j < XVECLEN (x, i); j++)
3233 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0, ht);
3239 /* Return a new hash table entry in HT. */
3241 static struct hash_entry *
3242 insns_for_mem_newfunc (he, ht, k)
3243 struct hash_entry *he;
3244 struct hash_table *ht;
3245 hash_table_key k ATTRIBUTE_UNUSED;
3247 struct insns_for_mem_entry *ifmhe;
3251 ifmhe = ((struct insns_for_mem_entry *)
3252 hash_allocate (ht, sizeof (struct insns_for_mem_entry)));
3253 ifmhe->insns = NULL_RTX;
3258 /* Return a hash value for K, a REG. */
3260 static unsigned long
3261 insns_for_mem_hash (k)
3264 /* K is really a RTX. Just use the address as the hash value. */
3265 return (unsigned long) k;
3268 /* Return non-zero if K1 and K2 (two REGs) are the same. */
3271 insns_for_mem_comp (k1, k2)
3278 struct insns_for_mem_walk_info {
3279 /* The hash table that we are using to record which INSNs use which
3281 struct hash_table *ht;
3283 /* The INSN we are currently proessing. */
3286 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3287 to find the insns that use the REGs in the ADDRESSOFs. */
3291 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3292 that might be used in an ADDRESSOF expression, record this INSN in
3293 the hash table given by DATA (which is really a pointer to an
3294 insns_for_mem_walk_info structure). */
3297 insns_for_mem_walk (r, data)
3301 struct insns_for_mem_walk_info *ifmwi
3302 = (struct insns_for_mem_walk_info *) data;
3304 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3305 && GET_CODE (XEXP (*r, 0)) == REG)
3306 hash_lookup (ifmwi->ht, XEXP (*r, 0), /*create=*/1, /*copy=*/0);
3307 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3309 /* Lookup this MEM in the hashtable, creating it if necessary. */
3310 struct insns_for_mem_entry *ifme
3311 = (struct insns_for_mem_entry *) hash_lookup (ifmwi->ht,
3316 /* If we have not already recorded this INSN, do so now. Since
3317 we process the INSNs in order, we know that if we have
3318 recorded it it must be at the front of the list. */
3319 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3320 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3327 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3328 which REGs in HT. */
3331 compute_insns_for_mem (insns, last_insn, ht)
3334 struct hash_table *ht;
3337 struct insns_for_mem_walk_info ifmwi;
3340 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3341 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3345 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3349 /* Helper function for purge_addressof called through for_each_rtx.
3350 Returns true iff the rtl is an ADDRESSOF. */
3353 is_addressof (rtl, data)
3355 void *data ATTRIBUTE_UNUSED;
3357 return GET_CODE (*rtl) == ADDRESSOF;
3360 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3361 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3365 purge_addressof (insns)
3369 struct hash_table ht;
3371 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3372 requires a fixup pass over the instruction stream to correct
3373 INSNs that depended on the REG being a REG, and not a MEM. But,
3374 these fixup passes are slow. Furthermore, most MEMs are not
3375 mentioned in very many instructions. So, we speed up the process
3376 by pre-calculating which REGs occur in which INSNs; that allows
3377 us to perform the fixup passes much more quickly. */
3378 hash_table_init (&ht,
3379 insns_for_mem_newfunc,
3381 insns_for_mem_comp);
3382 compute_insns_for_mem (insns, NULL_RTX, &ht);
3384 for (insn = insns; insn; insn = NEXT_INSN (insn))
3385 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3386 || GET_CODE (insn) == CALL_INSN)
3388 if (! purge_addressof_1 (&PATTERN (insn), insn,
3389 asm_noperands (PATTERN (insn)) > 0, 0, &ht))
3390 /* If we could not replace the ADDRESSOFs in the insn,
3391 something is wrong. */
3394 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, &ht))
3396 /* If we could not replace the ADDRESSOFs in the insn's notes,
3397 we can just remove the offending notes instead. */
3400 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3402 /* If we find a REG_RETVAL note then the insn is a libcall.
3403 Such insns must have REG_EQUAL notes as well, in order
3404 for later passes of the compiler to work. So it is not
3405 safe to delete the notes here, and instead we abort. */
3406 if (REG_NOTE_KIND (note) == REG_RETVAL)
3408 if (for_each_rtx (¬e, is_addressof, NULL))
3409 remove_note (insn, note);
3415 hash_table_free (&ht);
3416 purge_bitfield_addressof_replacements = 0;
3417 purge_addressof_replacements = 0;
3419 /* REGs are shared. purge_addressof will destructively replace a REG
3420 with a MEM, which creates shared MEMs.
3422 Unfortunately, the children of put_reg_into_stack assume that MEMs
3423 referring to the same stack slot are shared (fixup_var_refs and
3424 the associated hash table code).
3426 So, we have to do another unsharing pass after we have flushed any
3427 REGs that had their address taken into the stack.
3429 It may be worth tracking whether or not we converted any REGs into
3430 MEMs to avoid this overhead when it is not needed. */
3431 unshare_all_rtl_again (get_insns ());
3434 /* Convert a SET of a hard subreg to a set of the appropriet hard
3435 register. A subroutine of purge_hard_subreg_sets. */
3438 purge_single_hard_subreg_set (pattern)
3441 rtx reg = SET_DEST (pattern);
3442 enum machine_mode mode = GET_MODE (SET_DEST (pattern));
3445 if (GET_CODE (reg) == SUBREG && GET_CODE (SUBREG_REG (reg)) == REG
3446 && REGNO (SUBREG_REG (reg)) < FIRST_PSEUDO_REGISTER)
3448 offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)),
3449 GET_MODE (SUBREG_REG (reg)),
3452 reg = SUBREG_REG (reg);
3456 if (GET_CODE (reg) == REG && REGNO (reg) < FIRST_PSEUDO_REGISTER)
3458 reg = gen_rtx_REG (mode, REGNO (reg) + offset);
3459 SET_DEST (pattern) = reg;
3463 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The
3464 only such SETs that we expect to see are those left in because
3465 integrate can't handle sets of parts of a return value register.
3467 We don't use alter_subreg because we only want to eliminate subregs
3468 of hard registers. */
3471 purge_hard_subreg_sets (insn)
3474 for (; insn; insn = NEXT_INSN (insn))
3478 rtx pattern = PATTERN (insn);
3479 switch (GET_CODE (pattern))
3482 if (GET_CODE (SET_DEST (pattern)) == SUBREG)
3483 purge_single_hard_subreg_set (pattern);
3488 for (j = XVECLEN (pattern, 0) - 1; j >= 0; j--)
3490 rtx inner_pattern = XVECEXP (pattern, 0, j);
3491 if (GET_CODE (inner_pattern) == SET
3492 && GET_CODE (SET_DEST (inner_pattern)) == SUBREG)
3493 purge_single_hard_subreg_set (inner_pattern);
3504 /* Pass through the INSNS of function FNDECL and convert virtual register
3505 references to hard register references. */
3508 instantiate_virtual_regs (fndecl, insns)
3515 /* Compute the offsets to use for this function. */
3516 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3517 var_offset = STARTING_FRAME_OFFSET;
3518 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3519 out_arg_offset = STACK_POINTER_OFFSET;
3520 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl);
3522 /* Scan all variables and parameters of this function. For each that is
3523 in memory, instantiate all virtual registers if the result is a valid
3524 address. If not, we do it later. That will handle most uses of virtual
3525 regs on many machines. */
3526 instantiate_decls (fndecl, 1);
3528 /* Initialize recognition, indicating that volatile is OK. */
3531 /* Scan through all the insns, instantiating every virtual register still
3533 for (insn = insns; insn; insn = NEXT_INSN (insn))
3534 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3535 || GET_CODE (insn) == CALL_INSN)
3537 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3538 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3539 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
3540 if (GET_CODE (insn) == CALL_INSN)
3541 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn),
3545 /* Instantiate the stack slots for the parm registers, for later use in
3546 addressof elimination. */
3547 for (i = 0; i < max_parm_reg; ++i)
3548 if (parm_reg_stack_loc[i])
3549 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3551 /* Now instantiate the remaining register equivalences for debugging info.
3552 These will not be valid addresses. */
3553 instantiate_decls (fndecl, 0);
3555 /* Indicate that, from now on, assign_stack_local should use
3556 frame_pointer_rtx. */
3557 virtuals_instantiated = 1;
3560 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3561 all virtual registers in their DECL_RTL's.
3563 If VALID_ONLY, do this only if the resulting address is still valid.
3564 Otherwise, always do it. */
3567 instantiate_decls (fndecl, valid_only)
3573 /* Process all parameters of the function. */
3574 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3576 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3578 instantiate_decl (DECL_RTL (decl), size, valid_only);
3580 /* If the parameter was promoted, then the incoming RTL mode may be
3581 larger than the declared type size. We must use the larger of
3583 size = MAX (GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl))), size);
3584 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3587 /* Now process all variables defined in the function or its subblocks. */
3588 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3591 /* Subroutine of instantiate_decls: Process all decls in the given
3592 BLOCK node and all its subblocks. */
3595 instantiate_decls_1 (let, valid_only)
3601 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3602 if (DECL_RTL_SET_P (t))
3603 instantiate_decl (DECL_RTL (t),
3604 int_size_in_bytes (TREE_TYPE (t)),
3607 /* Process all subblocks. */
3608 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3609 instantiate_decls_1 (t, valid_only);
3612 /* Subroutine of the preceding procedures: Given RTL representing a
3613 decl and the size of the object, do any instantiation required.
3615 If VALID_ONLY is non-zero, it means that the RTL should only be
3616 changed if the new address is valid. */
3619 instantiate_decl (x, size, valid_only)
3624 enum machine_mode mode;
3627 /* If this is not a MEM, no need to do anything. Similarly if the
3628 address is a constant or a register that is not a virtual register. */
3630 if (x == 0 || GET_CODE (x) != MEM)
3634 if (CONSTANT_P (addr)
3635 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3636 || (GET_CODE (addr) == REG
3637 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3638 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3641 /* If we should only do this if the address is valid, copy the address.
3642 We need to do this so we can undo any changes that might make the
3643 address invalid. This copy is unfortunate, but probably can't be
3647 addr = copy_rtx (addr);
3649 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3651 if (valid_only && size >= 0)
3653 unsigned HOST_WIDE_INT decl_size = size;
3655 /* Now verify that the resulting address is valid for every integer or
3656 floating-point mode up to and including SIZE bytes long. We do this
3657 since the object might be accessed in any mode and frame addresses
3660 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3661 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3662 mode = GET_MODE_WIDER_MODE (mode))
3663 if (! memory_address_p (mode, addr))
3666 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3667 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3668 mode = GET_MODE_WIDER_MODE (mode))
3669 if (! memory_address_p (mode, addr))
3673 /* Put back the address now that we have updated it and we either know
3674 it is valid or we don't care whether it is valid. */
3679 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
3680 is a virtual register, return the requivalent hard register and set the
3681 offset indirectly through the pointer. Otherwise, return 0. */
3684 instantiate_new_reg (x, poffset)
3686 HOST_WIDE_INT *poffset;
3689 HOST_WIDE_INT offset;
3691 if (x == virtual_incoming_args_rtx)
3692 new = arg_pointer_rtx, offset = in_arg_offset;
3693 else if (x == virtual_stack_vars_rtx)
3694 new = frame_pointer_rtx, offset = var_offset;
3695 else if (x == virtual_stack_dynamic_rtx)
3696 new = stack_pointer_rtx, offset = dynamic_offset;
3697 else if (x == virtual_outgoing_args_rtx)
3698 new = stack_pointer_rtx, offset = out_arg_offset;
3699 else if (x == virtual_cfa_rtx)
3700 new = arg_pointer_rtx, offset = cfa_offset;
3708 /* Given a pointer to a piece of rtx and an optional pointer to the
3709 containing object, instantiate any virtual registers present in it.
3711 If EXTRA_INSNS, we always do the replacement and generate
3712 any extra insns before OBJECT. If it zero, we do nothing if replacement
3715 Return 1 if we either had nothing to do or if we were able to do the
3716 needed replacement. Return 0 otherwise; we only return zero if
3717 EXTRA_INSNS is zero.
3719 We first try some simple transformations to avoid the creation of extra
3723 instantiate_virtual_regs_1 (loc, object, extra_insns)
3731 HOST_WIDE_INT offset = 0;
3737 /* Re-start here to avoid recursion in common cases. */
3744 code = GET_CODE (x);
3746 /* Check for some special cases. */
3763 /* We are allowed to set the virtual registers. This means that
3764 the actual register should receive the source minus the
3765 appropriate offset. This is used, for example, in the handling
3766 of non-local gotos. */
3767 if ((new = instantiate_new_reg (SET_DEST (x), &offset)) != 0)
3769 rtx src = SET_SRC (x);
3771 /* We are setting the register, not using it, so the relevant
3772 offset is the negative of the offset to use were we using
3775 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3777 /* The only valid sources here are PLUS or REG. Just do
3778 the simplest possible thing to handle them. */
3779 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3783 if (GET_CODE (src) != REG)
3784 temp = force_operand (src, NULL_RTX);
3787 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3791 emit_insns_before (seq, object);
3794 if (! validate_change (object, &SET_SRC (x), temp, 0)
3801 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3806 /* Handle special case of virtual register plus constant. */
3807 if (CONSTANT_P (XEXP (x, 1)))
3809 rtx old, new_offset;
3811 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3812 if (GET_CODE (XEXP (x, 0)) == PLUS)
3814 if ((new = instantiate_new_reg (XEXP (XEXP (x, 0), 0), &offset)))
3816 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3818 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3827 #ifdef POINTERS_EXTEND_UNSIGNED
3828 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
3829 we can commute the PLUS and SUBREG because pointers into the
3830 frame are well-behaved. */
3831 else if (GET_CODE (XEXP (x, 0)) == SUBREG && GET_MODE (x) == ptr_mode
3832 && GET_CODE (XEXP (x, 1)) == CONST_INT
3834 = instantiate_new_reg (SUBREG_REG (XEXP (x, 0)),
3836 && validate_change (object, loc,
3837 plus_constant (gen_lowpart (ptr_mode,
3840 + INTVAL (XEXP (x, 1))),
3844 else if ((new = instantiate_new_reg (XEXP (x, 0), &offset)) == 0)
3846 /* We know the second operand is a constant. Unless the
3847 first operand is a REG (which has been already checked),
3848 it needs to be checked. */
3849 if (GET_CODE (XEXP (x, 0)) != REG)
3857 new_offset = plus_constant (XEXP (x, 1), offset);
3859 /* If the new constant is zero, try to replace the sum with just
3861 if (new_offset == const0_rtx
3862 && validate_change (object, loc, new, 0))
3865 /* Next try to replace the register and new offset.
3866 There are two changes to validate here and we can't assume that
3867 in the case of old offset equals new just changing the register
3868 will yield a valid insn. In the interests of a little efficiency,
3869 however, we only call validate change once (we don't queue up the
3870 changes and then call apply_change_group). */
3874 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3875 : (XEXP (x, 0) = new,
3876 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3884 /* Otherwise copy the new constant into a register and replace
3885 constant with that register. */
3886 temp = gen_reg_rtx (Pmode);
3888 if (validate_change (object, &XEXP (x, 1), temp, 0))
3889 emit_insn_before (gen_move_insn (temp, new_offset), object);
3892 /* If that didn't work, replace this expression with a
3893 register containing the sum. */
3896 new = gen_rtx_PLUS (Pmode, new, new_offset);
3899 temp = force_operand (new, NULL_RTX);
3903 emit_insns_before (seq, object);
3904 if (! validate_change (object, loc, temp, 0)
3905 && ! validate_replace_rtx (x, temp, object))
3913 /* Fall through to generic two-operand expression case. */
3919 case DIV: case UDIV:
3920 case MOD: case UMOD:
3921 case AND: case IOR: case XOR:
3922 case ROTATERT: case ROTATE:
3923 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3925 case GE: case GT: case GEU: case GTU:
3926 case LE: case LT: case LEU: case LTU:
3927 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3928 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3933 /* Most cases of MEM that convert to valid addresses have already been
3934 handled by our scan of decls. The only special handling we
3935 need here is to make a copy of the rtx to ensure it isn't being
3936 shared if we have to change it to a pseudo.
3938 If the rtx is a simple reference to an address via a virtual register,
3939 it can potentially be shared. In such cases, first try to make it
3940 a valid address, which can also be shared. Otherwise, copy it and
3943 First check for common cases that need no processing. These are
3944 usually due to instantiation already being done on a previous instance
3948 if (CONSTANT_ADDRESS_P (temp)
3949 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3950 || temp == arg_pointer_rtx
3952 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3953 || temp == hard_frame_pointer_rtx
3955 || temp == frame_pointer_rtx)
3958 if (GET_CODE (temp) == PLUS
3959 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3960 && (XEXP (temp, 0) == frame_pointer_rtx
3961 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3962 || XEXP (temp, 0) == hard_frame_pointer_rtx
3964 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3965 || XEXP (temp, 0) == arg_pointer_rtx
3970 if (temp == virtual_stack_vars_rtx
3971 || temp == virtual_incoming_args_rtx
3972 || (GET_CODE (temp) == PLUS
3973 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3974 && (XEXP (temp, 0) == virtual_stack_vars_rtx
3975 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
3977 /* This MEM may be shared. If the substitution can be done without
3978 the need to generate new pseudos, we want to do it in place
3979 so all copies of the shared rtx benefit. The call below will
3980 only make substitutions if the resulting address is still
3983 Note that we cannot pass X as the object in the recursive call
3984 since the insn being processed may not allow all valid
3985 addresses. However, if we were not passed on object, we can
3986 only modify X without copying it if X will have a valid
3989 ??? Also note that this can still lose if OBJECT is an insn that
3990 has less restrictions on an address that some other insn.
3991 In that case, we will modify the shared address. This case
3992 doesn't seem very likely, though. One case where this could
3993 happen is in the case of a USE or CLOBBER reference, but we
3994 take care of that below. */
3996 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
3997 object ? object : x, 0))
4000 /* Otherwise make a copy and process that copy. We copy the entire
4001 RTL expression since it might be a PLUS which could also be
4003 *loc = x = copy_rtx (x);
4006 /* Fall through to generic unary operation case. */
4008 case STRICT_LOW_PART:
4010 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
4011 case SIGN_EXTEND: case ZERO_EXTEND:
4012 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
4013 case FLOAT: case FIX:
4014 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
4018 /* These case either have just one operand or we know that we need not
4019 check the rest of the operands. */
4025 /* If the operand is a MEM, see if the change is a valid MEM. If not,
4026 go ahead and make the invalid one, but do it to a copy. For a REG,
4027 just make the recursive call, since there's no chance of a problem. */
4029 if ((GET_CODE (XEXP (x, 0)) == MEM
4030 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
4032 || (GET_CODE (XEXP (x, 0)) == REG
4033 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
4036 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
4041 /* Try to replace with a PLUS. If that doesn't work, compute the sum
4042 in front of this insn and substitute the temporary. */
4043 if ((new = instantiate_new_reg (x, &offset)) != 0)
4045 temp = plus_constant (new, offset);
4046 if (!validate_change (object, loc, temp, 0))
4052 temp = force_operand (temp, NULL_RTX);
4056 emit_insns_before (seq, object);
4057 if (! validate_change (object, loc, temp, 0)
4058 && ! validate_replace_rtx (x, temp, object))
4066 if (GET_CODE (XEXP (x, 0)) == REG)
4069 else if (GET_CODE (XEXP (x, 0)) == MEM)
4071 /* If we have a (addressof (mem ..)), do any instantiation inside
4072 since we know we'll be making the inside valid when we finally
4073 remove the ADDRESSOF. */
4074 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
4083 /* Scan all subexpressions. */
4084 fmt = GET_RTX_FORMAT (code);
4085 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
4088 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
4091 else if (*fmt == 'E')
4092 for (j = 0; j < XVECLEN (x, i); j++)
4093 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
4100 /* Optimization: assuming this function does not receive nonlocal gotos,
4101 delete the handlers for such, as well as the insns to establish
4102 and disestablish them. */
4108 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4110 /* Delete the handler by turning off the flag that would
4111 prevent jump_optimize from deleting it.
4112 Also permit deletion of the nonlocal labels themselves
4113 if nothing local refers to them. */
4114 if (GET_CODE (insn) == CODE_LABEL)
4118 LABEL_PRESERVE_P (insn) = 0;
4120 /* Remove it from the nonlocal_label list, to avoid confusing
4122 for (t = nonlocal_labels, last_t = 0; t;
4123 last_t = t, t = TREE_CHAIN (t))
4124 if (DECL_RTL (TREE_VALUE (t)) == insn)
4129 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
4131 TREE_CHAIN (last_t) = TREE_CHAIN (t);
4134 if (GET_CODE (insn) == INSN)
4138 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
4139 if (reg_mentioned_p (t, PATTERN (insn)))
4145 || (nonlocal_goto_stack_level != 0
4146 && reg_mentioned_p (nonlocal_goto_stack_level,
4156 return max_parm_reg;
4159 /* Return the first insn following those generated by `assign_parms'. */
4162 get_first_nonparm_insn ()
4165 return NEXT_INSN (last_parm_insn);
4166 return get_insns ();
4169 /* Return the first NOTE_INSN_BLOCK_BEG note in the function.
4170 Crash if there is none. */
4173 get_first_block_beg ()
4175 register rtx searcher;
4176 register rtx insn = get_first_nonparm_insn ();
4178 for (searcher = insn; searcher; searcher = NEXT_INSN (searcher))
4179 if (GET_CODE (searcher) == NOTE
4180 && NOTE_LINE_NUMBER (searcher) == NOTE_INSN_BLOCK_BEG)
4183 abort (); /* Invalid call to this function. (See comments above.) */
4187 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4188 This means a type for which function calls must pass an address to the
4189 function or get an address back from the function.
4190 EXP may be a type node or an expression (whose type is tested). */
4193 aggregate_value_p (exp)
4196 int i, regno, nregs;
4199 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4201 if (TREE_CODE (type) == VOID_TYPE)
4203 if (RETURN_IN_MEMORY (type))
4205 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4206 and thus can't be returned in registers. */
4207 if (TREE_ADDRESSABLE (type))
4209 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4211 /* Make sure we have suitable call-clobbered regs to return
4212 the value in; if not, we must return it in memory. */
4213 reg = hard_function_value (type, 0, 0);
4215 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4217 if (GET_CODE (reg) != REG)
4220 regno = REGNO (reg);
4221 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
4222 for (i = 0; i < nregs; i++)
4223 if (! call_used_regs[regno + i])
4228 /* Assign RTL expressions to the function's parameters.
4229 This may involve copying them into registers and using
4230 those registers as the RTL for them. */
4233 assign_parms (fndecl)
4237 register rtx entry_parm = 0;
4238 register rtx stack_parm = 0;
4239 CUMULATIVE_ARGS args_so_far;
4240 enum machine_mode promoted_mode, passed_mode;
4241 enum machine_mode nominal_mode, promoted_nominal_mode;
4243 /* Total space needed so far for args on the stack,
4244 given as a constant and a tree-expression. */
4245 struct args_size stack_args_size;
4246 tree fntype = TREE_TYPE (fndecl);
4247 tree fnargs = DECL_ARGUMENTS (fndecl);
4248 /* This is used for the arg pointer when referring to stack args. */
4249 rtx internal_arg_pointer;
4250 /* This is a dummy PARM_DECL that we used for the function result if
4251 the function returns a structure. */
4252 tree function_result_decl = 0;
4253 #ifdef SETUP_INCOMING_VARARGS
4254 int varargs_setup = 0;
4256 rtx conversion_insns = 0;
4257 struct args_size alignment_pad;
4259 /* Nonzero if the last arg is named `__builtin_va_alist',
4260 which is used on some machines for old-fashioned non-ANSI varargs.h;
4261 this should be stuck onto the stack as if it had arrived there. */
4263 = (current_function_varargs
4265 && (parm = tree_last (fnargs)) != 0
4267 && (! strcmp (IDENTIFIER_POINTER (DECL_NAME (parm)),
4268 "__builtin_va_alist")));
4270 /* Nonzero if function takes extra anonymous args.
4271 This means the last named arg must be on the stack
4272 right before the anonymous ones. */
4274 = (TYPE_ARG_TYPES (fntype) != 0
4275 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4276 != void_type_node));
4278 current_function_stdarg = stdarg;
4280 /* If the reg that the virtual arg pointer will be translated into is
4281 not a fixed reg or is the stack pointer, make a copy of the virtual
4282 arg pointer, and address parms via the copy. The frame pointer is
4283 considered fixed even though it is not marked as such.
4285 The second time through, simply use ap to avoid generating rtx. */
4287 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4288 || ! (fixed_regs[ARG_POINTER_REGNUM]
4289 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4290 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4292 internal_arg_pointer = virtual_incoming_args_rtx;
4293 current_function_internal_arg_pointer = internal_arg_pointer;
4295 stack_args_size.constant = 0;
4296 stack_args_size.var = 0;
4298 /* If struct value address is treated as the first argument, make it so. */
4299 if (aggregate_value_p (DECL_RESULT (fndecl))
4300 && ! current_function_returns_pcc_struct
4301 && struct_value_incoming_rtx == 0)
4303 tree type = build_pointer_type (TREE_TYPE (fntype));
4305 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4307 DECL_ARG_TYPE (function_result_decl) = type;
4308 TREE_CHAIN (function_result_decl) = fnargs;
4309 fnargs = function_result_decl;
4312 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4313 parm_reg_stack_loc = (rtx *) xcalloc (max_parm_reg, sizeof (rtx));
4315 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4316 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4318 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, 0);
4321 /* We haven't yet found an argument that we must push and pretend the
4323 current_function_pretend_args_size = 0;
4325 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4327 struct args_size stack_offset;
4328 struct args_size arg_size;
4329 int passed_pointer = 0;
4330 int did_conversion = 0;
4331 tree passed_type = DECL_ARG_TYPE (parm);
4332 tree nominal_type = TREE_TYPE (parm);
4335 /* Set LAST_NAMED if this is last named arg before some
4337 int last_named = ((TREE_CHAIN (parm) == 0
4338 || DECL_NAME (TREE_CHAIN (parm)) == 0)
4339 && (stdarg || current_function_varargs));
4340 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4341 most machines, if this is a varargs/stdarg function, then we treat
4342 the last named arg as if it were anonymous too. */
4343 int named_arg = STRICT_ARGUMENT_NAMING ? 1 : ! last_named;
4345 if (TREE_TYPE (parm) == error_mark_node
4346 /* This can happen after weird syntax errors
4347 or if an enum type is defined among the parms. */
4348 || TREE_CODE (parm) != PARM_DECL
4349 || passed_type == NULL)
4351 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx));
4352 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4353 TREE_USED (parm) = 1;
4357 /* For varargs.h function, save info about regs and stack space
4358 used by the individual args, not including the va_alist arg. */
4359 if (hide_last_arg && last_named)
4360 current_function_args_info = args_so_far;
4362 /* Find mode of arg as it is passed, and mode of arg
4363 as it should be during execution of this function. */
4364 passed_mode = TYPE_MODE (passed_type);
4365 nominal_mode = TYPE_MODE (nominal_type);
4367 /* If the parm's mode is VOID, its value doesn't matter,
4368 and avoid the usual things like emit_move_insn that could crash. */
4369 if (nominal_mode == VOIDmode)
4371 SET_DECL_RTL (parm, const0_rtx);
4372 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4376 /* If the parm is to be passed as a transparent union, use the
4377 type of the first field for the tests below. We have already
4378 verified that the modes are the same. */
4379 if (DECL_TRANSPARENT_UNION (parm)
4380 || (TREE_CODE (passed_type) == UNION_TYPE
4381 && TYPE_TRANSPARENT_UNION (passed_type)))
4382 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4384 /* See if this arg was passed by invisible reference. It is if
4385 it is an object whose size depends on the contents of the
4386 object itself or if the machine requires these objects be passed
4389 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
4390 && contains_placeholder_p (TYPE_SIZE (passed_type)))
4391 || TREE_ADDRESSABLE (passed_type)
4392 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4393 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4394 passed_type, named_arg)
4398 passed_type = nominal_type = build_pointer_type (passed_type);
4400 passed_mode = nominal_mode = Pmode;
4403 promoted_mode = passed_mode;
4405 #ifdef PROMOTE_FUNCTION_ARGS
4406 /* Compute the mode in which the arg is actually extended to. */
4407 unsignedp = TREE_UNSIGNED (passed_type);
4408 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4411 /* Let machine desc say which reg (if any) the parm arrives in.
4412 0 means it arrives on the stack. */
4413 #ifdef FUNCTION_INCOMING_ARG
4414 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4415 passed_type, named_arg);
4417 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4418 passed_type, named_arg);
4421 if (entry_parm == 0)
4422 promoted_mode = passed_mode;
4424 #ifdef SETUP_INCOMING_VARARGS
4425 /* If this is the last named parameter, do any required setup for
4426 varargs or stdargs. We need to know about the case of this being an
4427 addressable type, in which case we skip the registers it
4428 would have arrived in.
4430 For stdargs, LAST_NAMED will be set for two parameters, the one that
4431 is actually the last named, and the dummy parameter. We only
4432 want to do this action once.
4434 Also, indicate when RTL generation is to be suppressed. */
4435 if (last_named && !varargs_setup)
4437 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
4438 current_function_pretend_args_size, 0);
4443 /* Determine parm's home in the stack,
4444 in case it arrives in the stack or we should pretend it did.
4446 Compute the stack position and rtx where the argument arrives
4449 There is one complexity here: If this was a parameter that would
4450 have been passed in registers, but wasn't only because it is
4451 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4452 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4453 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4454 0 as it was the previous time. */
4456 pretend_named = named_arg || PRETEND_OUTGOING_VARARGS_NAMED;
4457 locate_and_pad_parm (promoted_mode, passed_type,
4458 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4461 #ifdef FUNCTION_INCOMING_ARG
4462 FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4464 pretend_named) != 0,
4466 FUNCTION_ARG (args_so_far, promoted_mode,
4468 pretend_named) != 0,
4471 fndecl, &stack_args_size, &stack_offset, &arg_size,
4475 rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
4477 if (offset_rtx == const0_rtx)
4478 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4480 stack_parm = gen_rtx_MEM (promoted_mode,
4481 gen_rtx_PLUS (Pmode,
4482 internal_arg_pointer,
4485 set_mem_attributes (stack_parm, parm, 1);
4488 /* If this parameter was passed both in registers and in the stack,
4489 use the copy on the stack. */
4490 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4493 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4494 /* If this parm was passed part in regs and part in memory,
4495 pretend it arrived entirely in memory
4496 by pushing the register-part onto the stack.
4498 In the special case of a DImode or DFmode that is split,
4499 we could put it together in a pseudoreg directly,
4500 but for now that's not worth bothering with. */
4504 int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4505 passed_type, named_arg);
4509 current_function_pretend_args_size
4510 = (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
4511 / (PARM_BOUNDARY / BITS_PER_UNIT)
4512 * (PARM_BOUNDARY / BITS_PER_UNIT));
4514 /* Handle calls that pass values in multiple non-contiguous
4515 locations. The Irix 6 ABI has examples of this. */
4516 if (GET_CODE (entry_parm) == PARALLEL)
4517 emit_group_store (validize_mem (stack_parm), entry_parm,
4518 int_size_in_bytes (TREE_TYPE (parm)),
4519 TYPE_ALIGN (TREE_TYPE (parm)));
4522 move_block_from_reg (REGNO (entry_parm),
4523 validize_mem (stack_parm), nregs,
4524 int_size_in_bytes (TREE_TYPE (parm)));
4526 entry_parm = stack_parm;
4531 /* If we didn't decide this parm came in a register,
4532 by default it came on the stack. */
4533 if (entry_parm == 0)
4534 entry_parm = stack_parm;
4536 /* Record permanently how this parm was passed. */
4537 DECL_INCOMING_RTL (parm) = entry_parm;
4539 /* If there is actually space on the stack for this parm,
4540 count it in stack_args_size; otherwise set stack_parm to 0
4541 to indicate there is no preallocated stack slot for the parm. */
4543 if (entry_parm == stack_parm
4544 || (GET_CODE (entry_parm) == PARALLEL
4545 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4546 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4547 /* On some machines, even if a parm value arrives in a register
4548 there is still an (uninitialized) stack slot allocated for it.
4550 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4551 whether this parameter already has a stack slot allocated,
4552 because an arg block exists only if current_function_args_size
4553 is larger than some threshold, and we haven't calculated that
4554 yet. So, for now, we just assume that stack slots never exist
4556 || REG_PARM_STACK_SPACE (fndecl) > 0
4560 stack_args_size.constant += arg_size.constant;
4562 ADD_PARM_SIZE (stack_args_size, arg_size.var);
4565 /* No stack slot was pushed for this parm. */
4568 /* Update info on where next arg arrives in registers. */
4570 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4571 passed_type, named_arg);
4573 /* If we can't trust the parm stack slot to be aligned enough
4574 for its ultimate type, don't use that slot after entry.
4575 We'll make another stack slot, if we need one. */
4577 unsigned int thisparm_boundary
4578 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4580 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4584 /* If parm was passed in memory, and we need to convert it on entry,
4585 don't store it back in that same slot. */
4587 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4590 /* When an argument is passed in multiple locations, we can't
4591 make use of this information, but we can save some copying if
4592 the whole argument is passed in a single register. */
4593 if (GET_CODE (entry_parm) == PARALLEL
4594 && nominal_mode != BLKmode && passed_mode != BLKmode)
4596 int i, len = XVECLEN (entry_parm, 0);
4598 for (i = 0; i < len; i++)
4599 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
4600 && GET_CODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) == REG
4601 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
4603 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
4605 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
4606 DECL_INCOMING_RTL (parm) = entry_parm;
4611 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4612 in the mode in which it arrives.
4613 STACK_PARM is an RTX for a stack slot where the parameter can live
4614 during the function (in case we want to put it there).
4615 STACK_PARM is 0 if no stack slot was pushed for it.
4617 Now output code if necessary to convert ENTRY_PARM to
4618 the type in which this function declares it,
4619 and store that result in an appropriate place,
4620 which may be a pseudo reg, may be STACK_PARM,
4621 or may be a local stack slot if STACK_PARM is 0.
4623 Set DECL_RTL to that place. */
4625 if (nominal_mode == BLKmode || GET_CODE (entry_parm) == PARALLEL)
4627 /* If a BLKmode arrives in registers, copy it to a stack slot.
4628 Handle calls that pass values in multiple non-contiguous
4629 locations. The Irix 6 ABI has examples of this. */
4630 if (GET_CODE (entry_parm) == REG
4631 || GET_CODE (entry_parm) == PARALLEL)
4634 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
4637 /* Note that we will be storing an integral number of words.
4638 So we have to be careful to ensure that we allocate an
4639 integral number of words. We do this below in the
4640 assign_stack_local if space was not allocated in the argument
4641 list. If it was, this will not work if PARM_BOUNDARY is not
4642 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4643 if it becomes a problem. */
4645 if (stack_parm == 0)
4648 = assign_stack_local (GET_MODE (entry_parm),
4650 set_mem_attributes (stack_parm, parm, 1);
4653 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4656 /* Handle calls that pass values in multiple non-contiguous
4657 locations. The Irix 6 ABI has examples of this. */
4658 if (GET_CODE (entry_parm) == PARALLEL)
4659 emit_group_store (validize_mem (stack_parm), entry_parm,
4660 int_size_in_bytes (TREE_TYPE (parm)),
4661 TYPE_ALIGN (TREE_TYPE (parm)));
4663 move_block_from_reg (REGNO (entry_parm),
4664 validize_mem (stack_parm),
4665 size_stored / UNITS_PER_WORD,
4666 int_size_in_bytes (TREE_TYPE (parm)));
4668 SET_DECL_RTL (parm, stack_parm);
4670 else if (! ((! optimize
4671 && ! DECL_REGISTER (parm)
4672 && ! DECL_INLINE (fndecl))
4673 || TREE_SIDE_EFFECTS (parm)
4674 /* If -ffloat-store specified, don't put explicit
4675 float variables into registers. */
4676 || (flag_float_store
4677 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4678 /* Always assign pseudo to structure return or item passed
4679 by invisible reference. */
4680 || passed_pointer || parm == function_result_decl)
4682 /* Store the parm in a pseudoregister during the function, but we
4683 may need to do it in a wider mode. */
4685 register rtx parmreg;
4686 unsigned int regno, regnoi = 0, regnor = 0;
4688 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4690 promoted_nominal_mode
4691 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4693 parmreg = gen_reg_rtx (promoted_nominal_mode);
4694 mark_user_reg (parmreg);
4696 /* If this was an item that we received a pointer to, set DECL_RTL
4701 gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)),
4703 set_mem_attributes (DECL_RTL (parm), parm, 1);
4707 SET_DECL_RTL (parm, parmreg);
4708 maybe_set_unchanging (DECL_RTL (parm), parm);
4711 /* Copy the value into the register. */
4712 if (nominal_mode != passed_mode
4713 || promoted_nominal_mode != promoted_mode)
4716 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4717 mode, by the caller. We now have to convert it to
4718 NOMINAL_MODE, if different. However, PARMREG may be in
4719 a different mode than NOMINAL_MODE if it is being stored
4722 If ENTRY_PARM is a hard register, it might be in a register
4723 not valid for operating in its mode (e.g., an odd-numbered
4724 register for a DFmode). In that case, moves are the only
4725 thing valid, so we can't do a convert from there. This
4726 occurs when the calling sequence allow such misaligned
4729 In addition, the conversion may involve a call, which could
4730 clobber parameters which haven't been copied to pseudo
4731 registers yet. Therefore, we must first copy the parm to
4732 a pseudo reg here, and save the conversion until after all
4733 parameters have been moved. */
4735 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4737 emit_move_insn (tempreg, validize_mem (entry_parm));
4739 push_to_sequence (conversion_insns);
4740 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4742 if (GET_CODE (tempreg) == SUBREG
4743 && GET_MODE (tempreg) == nominal_mode
4744 && GET_CODE (SUBREG_REG (tempreg)) == REG
4745 && nominal_mode == passed_mode
4746 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm)
4747 && GET_MODE_SIZE (GET_MODE (tempreg))
4748 < GET_MODE_SIZE (GET_MODE (entry_parm)))
4750 /* The argument is already sign/zero extended, so note it
4752 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
4753 SUBREG_PROMOTED_UNSIGNED_P (tempreg) = unsignedp;
4756 /* TREE_USED gets set erroneously during expand_assignment. */
4757 save_tree_used = TREE_USED (parm);
4758 expand_assignment (parm,
4759 make_tree (nominal_type, tempreg), 0, 0);
4760 TREE_USED (parm) = save_tree_used;
4761 conversion_insns = get_insns ();
4766 emit_move_insn (parmreg, validize_mem (entry_parm));
4768 /* If we were passed a pointer but the actual value
4769 can safely live in a register, put it in one. */
4770 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4772 && ! DECL_REGISTER (parm)
4773 && ! DECL_INLINE (fndecl))
4774 || TREE_SIDE_EFFECTS (parm)
4775 /* If -ffloat-store specified, don't put explicit
4776 float variables into registers. */
4777 || (flag_float_store
4778 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE)))
4780 /* We can't use nominal_mode, because it will have been set to
4781 Pmode above. We must use the actual mode of the parm. */
4782 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4783 mark_user_reg (parmreg);
4784 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
4786 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
4787 int unsigned_p = TREE_UNSIGNED (TREE_TYPE (parm));
4788 push_to_sequence (conversion_insns);
4789 emit_move_insn (tempreg, DECL_RTL (parm));
4791 convert_to_mode (GET_MODE (parmreg),
4794 emit_move_insn (parmreg, DECL_RTL (parm));
4795 conversion_insns = get_insns();
4800 emit_move_insn (parmreg, DECL_RTL (parm));
4801 SET_DECL_RTL (parm, parmreg);
4802 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4806 #ifdef FUNCTION_ARG_CALLEE_COPIES
4807 /* If we are passed an arg by reference and it is our responsibility
4808 to make a copy, do it now.
4809 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4810 original argument, so we must recreate them in the call to
4811 FUNCTION_ARG_CALLEE_COPIES. */
4812 /* ??? Later add code to handle the case that if the argument isn't
4813 modified, don't do the copy. */
4815 else if (passed_pointer
4816 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4817 TYPE_MODE (DECL_ARG_TYPE (parm)),
4818 DECL_ARG_TYPE (parm),
4820 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4823 tree type = DECL_ARG_TYPE (parm);
4825 /* This sequence may involve a library call perhaps clobbering
4826 registers that haven't been copied to pseudos yet. */
4828 push_to_sequence (conversion_insns);
4830 if (!COMPLETE_TYPE_P (type)
4831 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4832 /* This is a variable sized object. */
4833 copy = gen_rtx_MEM (BLKmode,
4834 allocate_dynamic_stack_space
4835 (expr_size (parm), NULL_RTX,
4836 TYPE_ALIGN (type)));
4838 copy = assign_stack_temp (TYPE_MODE (type),
4839 int_size_in_bytes (type), 1);
4840 set_mem_attributes (copy, parm, 1);
4842 store_expr (parm, copy, 0);
4843 emit_move_insn (parmreg, XEXP (copy, 0));
4844 if (current_function_check_memory_usage)
4845 emit_library_call (chkr_set_right_libfunc,
4846 LCT_CONST_MAKE_BLOCK, VOIDmode, 3,
4847 XEXP (copy, 0), Pmode,
4848 GEN_INT (int_size_in_bytes (type)),
4849 TYPE_MODE (sizetype),
4850 GEN_INT (MEMORY_USE_RW),
4851 TYPE_MODE (integer_type_node));
4852 conversion_insns = get_insns ();
4856 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4858 /* In any case, record the parm's desired stack location
4859 in case we later discover it must live in the stack.
4861 If it is a COMPLEX value, store the stack location for both
4864 if (GET_CODE (parmreg) == CONCAT)
4865 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4867 regno = REGNO (parmreg);
4869 if (regno >= max_parm_reg)
4872 int old_max_parm_reg = max_parm_reg;
4874 /* It's slow to expand this one register at a time,
4875 but it's also rare and we need max_parm_reg to be
4876 precisely correct. */
4877 max_parm_reg = regno + 1;
4878 new = (rtx *) xrealloc (parm_reg_stack_loc,
4879 max_parm_reg * sizeof (rtx));
4880 memset ((char *) (new + old_max_parm_reg), 0,
4881 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4882 parm_reg_stack_loc = new;
4885 if (GET_CODE (parmreg) == CONCAT)
4887 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
4889 regnor = REGNO (gen_realpart (submode, parmreg));
4890 regnoi = REGNO (gen_imagpart (submode, parmreg));
4892 if (stack_parm != 0)
4894 parm_reg_stack_loc[regnor]
4895 = gen_realpart (submode, stack_parm);
4896 parm_reg_stack_loc[regnoi]
4897 = gen_imagpart (submode, stack_parm);
4901 parm_reg_stack_loc[regnor] = 0;
4902 parm_reg_stack_loc[regnoi] = 0;
4906 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
4908 /* Mark the register as eliminable if we did no conversion
4909 and it was copied from memory at a fixed offset,
4910 and the arg pointer was not copied to a pseudo-reg.
4911 If the arg pointer is a pseudo reg or the offset formed
4912 an invalid address, such memory-equivalences
4913 as we make here would screw up life analysis for it. */
4914 if (nominal_mode == passed_mode
4917 && GET_CODE (stack_parm) == MEM
4918 && stack_offset.var == 0
4919 && reg_mentioned_p (virtual_incoming_args_rtx,
4920 XEXP (stack_parm, 0)))
4922 rtx linsn = get_last_insn ();
4925 /* Mark complex types separately. */
4926 if (GET_CODE (parmreg) == CONCAT)
4927 /* Scan backwards for the set of the real and
4929 for (sinsn = linsn; sinsn != 0;
4930 sinsn = prev_nonnote_insn (sinsn))
4932 set = single_set (sinsn);
4934 && SET_DEST (set) == regno_reg_rtx [regnoi])
4936 = gen_rtx_EXPR_LIST (REG_EQUIV,
4937 parm_reg_stack_loc[regnoi],
4940 && SET_DEST (set) == regno_reg_rtx [regnor])
4942 = gen_rtx_EXPR_LIST (REG_EQUIV,
4943 parm_reg_stack_loc[regnor],
4946 else if ((set = single_set (linsn)) != 0
4947 && SET_DEST (set) == parmreg)
4949 = gen_rtx_EXPR_LIST (REG_EQUIV,
4950 stack_parm, REG_NOTES (linsn));
4953 /* For pointer data type, suggest pointer register. */
4954 if (POINTER_TYPE_P (TREE_TYPE (parm)))
4955 mark_reg_pointer (parmreg,
4956 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
4958 /* If something wants our address, try to use ADDRESSOF. */
4959 if (TREE_ADDRESSABLE (parm))
4961 /* If we end up putting something into the stack,
4962 fixup_var_refs_insns will need to make a pass over
4963 all the instructions. It looks throughs the pending
4964 sequences -- but it can't see the ones in the
4965 CONVERSION_INSNS, if they're not on the sequence
4966 stack. So, we go back to that sequence, just so that
4967 the fixups will happen. */
4968 push_to_sequence (conversion_insns);
4969 put_var_into_stack (parm);
4970 conversion_insns = get_insns ();
4976 /* Value must be stored in the stack slot STACK_PARM
4977 during function execution. */
4979 if (promoted_mode != nominal_mode)
4981 /* Conversion is required. */
4982 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4984 emit_move_insn (tempreg, validize_mem (entry_parm));
4986 push_to_sequence (conversion_insns);
4987 entry_parm = convert_to_mode (nominal_mode, tempreg,
4988 TREE_UNSIGNED (TREE_TYPE (parm)));
4990 /* ??? This may need a big-endian conversion on sparc64. */
4991 stack_parm = adjust_address (stack_parm, nominal_mode, 0);
4993 conversion_insns = get_insns ();
4998 if (entry_parm != stack_parm)
5000 if (stack_parm == 0)
5003 = assign_stack_local (GET_MODE (entry_parm),
5004 GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
5005 set_mem_attributes (stack_parm, parm, 1);
5008 if (promoted_mode != nominal_mode)
5010 push_to_sequence (conversion_insns);
5011 emit_move_insn (validize_mem (stack_parm),
5012 validize_mem (entry_parm));
5013 conversion_insns = get_insns ();
5017 emit_move_insn (validize_mem (stack_parm),
5018 validize_mem (entry_parm));
5020 if (current_function_check_memory_usage)
5022 push_to_sequence (conversion_insns);
5023 emit_library_call (chkr_set_right_libfunc, LCT_CONST_MAKE_BLOCK,
5024 VOIDmode, 3, XEXP (stack_parm, 0), Pmode,
5025 GEN_INT (GET_MODE_SIZE (GET_MODE
5027 TYPE_MODE (sizetype),
5028 GEN_INT (MEMORY_USE_RW),
5029 TYPE_MODE (integer_type_node));
5031 conversion_insns = get_insns ();
5034 SET_DECL_RTL (parm, stack_parm);
5037 /* If this "parameter" was the place where we are receiving the
5038 function's incoming structure pointer, set up the result. */
5039 if (parm == function_result_decl)
5041 tree result = DECL_RESULT (fndecl);
5043 SET_DECL_RTL (result,
5044 gen_rtx_MEM (DECL_MODE (result), DECL_RTL (parm)));
5046 set_mem_attributes (DECL_RTL (result), result, 1);
5050 /* Output all parameter conversion instructions (possibly including calls)
5051 now that all parameters have been copied out of hard registers. */
5052 emit_insns (conversion_insns);
5054 last_parm_insn = get_last_insn ();
5056 current_function_args_size = stack_args_size.constant;
5058 /* Adjust function incoming argument size for alignment and
5061 #ifdef REG_PARM_STACK_SPACE
5062 #ifndef MAYBE_REG_PARM_STACK_SPACE
5063 current_function_args_size = MAX (current_function_args_size,
5064 REG_PARM_STACK_SPACE (fndecl));
5068 #ifdef STACK_BOUNDARY
5069 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
5071 current_function_args_size
5072 = ((current_function_args_size + STACK_BYTES - 1)
5073 / STACK_BYTES) * STACK_BYTES;
5076 #ifdef ARGS_GROW_DOWNWARD
5077 current_function_arg_offset_rtx
5078 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
5079 : expand_expr (size_diffop (stack_args_size.var,
5080 size_int (-stack_args_size.constant)),
5081 NULL_RTX, VOIDmode, EXPAND_MEMORY_USE_BAD));
5083 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
5086 /* See how many bytes, if any, of its args a function should try to pop
5089 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
5090 current_function_args_size);
5092 /* For stdarg.h function, save info about
5093 regs and stack space used by the named args. */
5096 current_function_args_info = args_so_far;
5098 /* Set the rtx used for the function return value. Put this in its
5099 own variable so any optimizers that need this information don't have
5100 to include tree.h. Do this here so it gets done when an inlined
5101 function gets output. */
5103 current_function_return_rtx
5104 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
5105 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
5108 /* Indicate whether REGNO is an incoming argument to the current function
5109 that was promoted to a wider mode. If so, return the RTX for the
5110 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5111 that REGNO is promoted from and whether the promotion was signed or
5114 #ifdef PROMOTE_FUNCTION_ARGS
5117 promoted_input_arg (regno, pmode, punsignedp)
5119 enum machine_mode *pmode;
5124 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
5125 arg = TREE_CHAIN (arg))
5126 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
5127 && REGNO (DECL_INCOMING_RTL (arg)) == regno
5128 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
5130 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
5131 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
5133 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
5134 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
5135 && mode != DECL_MODE (arg))
5137 *pmode = DECL_MODE (arg);
5138 *punsignedp = unsignedp;
5139 return DECL_INCOMING_RTL (arg);
5148 /* Compute the size and offset from the start of the stacked arguments for a
5149 parm passed in mode PASSED_MODE and with type TYPE.
5151 INITIAL_OFFSET_PTR points to the current offset into the stacked
5154 The starting offset and size for this parm are returned in *OFFSET_PTR
5155 and *ARG_SIZE_PTR, respectively.
5157 IN_REGS is non-zero if the argument will be passed in registers. It will
5158 never be set if REG_PARM_STACK_SPACE is not defined.
5160 FNDECL is the function in which the argument was defined.
5162 There are two types of rounding that are done. The first, controlled by
5163 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5164 list to be aligned to the specific boundary (in bits). This rounding
5165 affects the initial and starting offsets, but not the argument size.
5167 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5168 optionally rounds the size of the parm to PARM_BOUNDARY. The
5169 initial offset is not affected by this rounding, while the size always
5170 is and the starting offset may be. */
5172 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
5173 initial_offset_ptr is positive because locate_and_pad_parm's
5174 callers pass in the total size of args so far as
5175 initial_offset_ptr. arg_size_ptr is always positive.*/
5178 locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
5179 initial_offset_ptr, offset_ptr, arg_size_ptr,
5181 enum machine_mode passed_mode;
5183 int in_regs ATTRIBUTE_UNUSED;
5184 tree fndecl ATTRIBUTE_UNUSED;
5185 struct args_size *initial_offset_ptr;
5186 struct args_size *offset_ptr;
5187 struct args_size *arg_size_ptr;
5188 struct args_size *alignment_pad;
5192 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5193 enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5194 int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5196 #ifdef REG_PARM_STACK_SPACE
5197 /* If we have found a stack parm before we reach the end of the
5198 area reserved for registers, skip that area. */
5201 int reg_parm_stack_space = 0;
5203 #ifdef MAYBE_REG_PARM_STACK_SPACE
5204 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
5206 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5208 if (reg_parm_stack_space > 0)
5210 if (initial_offset_ptr->var)
5212 initial_offset_ptr->var
5213 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5214 ssize_int (reg_parm_stack_space));
5215 initial_offset_ptr->constant = 0;
5217 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5218 initial_offset_ptr->constant = reg_parm_stack_space;
5221 #endif /* REG_PARM_STACK_SPACE */
5223 arg_size_ptr->var = 0;
5224 arg_size_ptr->constant = 0;
5225 alignment_pad->var = 0;
5226 alignment_pad->constant = 0;
5228 #ifdef ARGS_GROW_DOWNWARD
5229 if (initial_offset_ptr->var)
5231 offset_ptr->constant = 0;
5232 offset_ptr->var = size_binop (MINUS_EXPR, ssize_int (0),
5233 initial_offset_ptr->var);
5237 offset_ptr->constant = -initial_offset_ptr->constant;
5238 offset_ptr->var = 0;
5240 if (where_pad != none
5241 && (!host_integerp (sizetree, 1)
5242 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5243 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5244 SUB_PARM_SIZE (*offset_ptr, sizetree);
5245 if (where_pad != downward)
5246 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad);
5247 if (initial_offset_ptr->var)
5248 arg_size_ptr->var = size_binop (MINUS_EXPR,
5249 size_binop (MINUS_EXPR,
5251 initial_offset_ptr->var),
5255 arg_size_ptr->constant = (-initial_offset_ptr->constant
5256 - offset_ptr->constant);
5258 #else /* !ARGS_GROW_DOWNWARD */
5260 #ifdef REG_PARM_STACK_SPACE
5261 || REG_PARM_STACK_SPACE (fndecl) > 0
5264 pad_to_arg_alignment (initial_offset_ptr, boundary, alignment_pad);
5265 *offset_ptr = *initial_offset_ptr;
5267 #ifdef PUSH_ROUNDING
5268 if (passed_mode != BLKmode)
5269 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5272 /* Pad_below needs the pre-rounded size to know how much to pad below
5273 so this must be done before rounding up. */
5274 if (where_pad == downward
5275 /* However, BLKmode args passed in regs have their padding done elsewhere.
5276 The stack slot must be able to hold the entire register. */
5277 && !(in_regs && passed_mode == BLKmode))
5278 pad_below (offset_ptr, passed_mode, sizetree);
5280 if (where_pad != none
5281 && (!host_integerp (sizetree, 1)
5282 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5283 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5285 ADD_PARM_SIZE (*arg_size_ptr, sizetree);
5286 #endif /* ARGS_GROW_DOWNWARD */
5289 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5290 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5293 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad)
5294 struct args_size *offset_ptr;
5296 struct args_size *alignment_pad;
5298 tree save_var = NULL_TREE;
5299 HOST_WIDE_INT save_constant = 0;
5301 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5303 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5305 save_var = offset_ptr->var;
5306 save_constant = offset_ptr->constant;
5309 alignment_pad->var = NULL_TREE;
5310 alignment_pad->constant = 0;
5312 if (boundary > BITS_PER_UNIT)
5314 if (offset_ptr->var)
5317 #ifdef ARGS_GROW_DOWNWARD
5322 (ARGS_SIZE_TREE (*offset_ptr),
5323 boundary / BITS_PER_UNIT);
5324 offset_ptr->constant = 0; /*?*/
5325 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5326 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5331 offset_ptr->constant =
5332 #ifdef ARGS_GROW_DOWNWARD
5333 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
5335 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
5337 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5338 alignment_pad->constant = offset_ptr->constant - save_constant;
5343 #ifndef ARGS_GROW_DOWNWARD
5345 pad_below (offset_ptr, passed_mode, sizetree)
5346 struct args_size *offset_ptr;
5347 enum machine_mode passed_mode;
5350 if (passed_mode != BLKmode)
5352 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5353 offset_ptr->constant
5354 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5355 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5356 - GET_MODE_SIZE (passed_mode));
5360 if (TREE_CODE (sizetree) != INTEGER_CST
5361 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5363 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5364 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5366 ADD_PARM_SIZE (*offset_ptr, s2);
5367 SUB_PARM_SIZE (*offset_ptr, sizetree);
5373 /* Walk the tree of blocks describing the binding levels within a function
5374 and warn about uninitialized variables.
5375 This is done after calling flow_analysis and before global_alloc
5376 clobbers the pseudo-regs to hard regs. */
5379 uninitialized_vars_warning (block)
5382 register tree decl, sub;
5383 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5385 if (warn_uninitialized
5386 && TREE_CODE (decl) == VAR_DECL
5387 /* These warnings are unreliable for and aggregates
5388 because assigning the fields one by one can fail to convince
5389 flow.c that the entire aggregate was initialized.
5390 Unions are troublesome because members may be shorter. */
5391 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5392 && DECL_RTL (decl) != 0
5393 && GET_CODE (DECL_RTL (decl)) == REG
5394 /* Global optimizations can make it difficult to determine if a
5395 particular variable has been initialized. However, a VAR_DECL
5396 with a nonzero DECL_INITIAL had an initializer, so do not
5397 claim it is potentially uninitialized.
5399 We do not care about the actual value in DECL_INITIAL, so we do
5400 not worry that it may be a dangling pointer. */
5401 && DECL_INITIAL (decl) == NULL_TREE
5402 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5403 warning_with_decl (decl,
5404 "`%s' might be used uninitialized in this function");
5406 && TREE_CODE (decl) == VAR_DECL
5407 && DECL_RTL (decl) != 0
5408 && GET_CODE (DECL_RTL (decl)) == REG
5409 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5410 warning_with_decl (decl,
5411 "variable `%s' might be clobbered by `longjmp' or `vfork'");
5413 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5414 uninitialized_vars_warning (sub);
5417 /* Do the appropriate part of uninitialized_vars_warning
5418 but for arguments instead of local variables. */
5421 setjmp_args_warning ()
5424 for (decl = DECL_ARGUMENTS (current_function_decl);
5425 decl; decl = TREE_CHAIN (decl))
5426 if (DECL_RTL (decl) != 0
5427 && GET_CODE (DECL_RTL (decl)) == REG
5428 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5429 warning_with_decl (decl,
5430 "argument `%s' might be clobbered by `longjmp' or `vfork'");
5433 /* If this function call setjmp, put all vars into the stack
5434 unless they were declared `register'. */
5437 setjmp_protect (block)
5440 register tree decl, sub;
5441 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5442 if ((TREE_CODE (decl) == VAR_DECL
5443 || TREE_CODE (decl) == PARM_DECL)
5444 && DECL_RTL (decl) != 0
5445 && (GET_CODE (DECL_RTL (decl)) == REG
5446 || (GET_CODE (DECL_RTL (decl)) == MEM
5447 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5448 /* If this variable came from an inline function, it must be
5449 that its life doesn't overlap the setjmp. If there was a
5450 setjmp in the function, it would already be in memory. We
5451 must exclude such variable because their DECL_RTL might be
5452 set to strange things such as virtual_stack_vars_rtx. */
5453 && ! DECL_FROM_INLINE (decl)
5455 #ifdef NON_SAVING_SETJMP
5456 /* If longjmp doesn't restore the registers,
5457 don't put anything in them. */
5461 ! DECL_REGISTER (decl)))
5462 put_var_into_stack (decl);
5463 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5464 setjmp_protect (sub);
5467 /* Like the previous function, but for args instead of local variables. */
5470 setjmp_protect_args ()
5473 for (decl = DECL_ARGUMENTS (current_function_decl);
5474 decl; decl = TREE_CHAIN (decl))
5475 if ((TREE_CODE (decl) == VAR_DECL
5476 || TREE_CODE (decl) == PARM_DECL)
5477 && DECL_RTL (decl) != 0
5478 && (GET_CODE (DECL_RTL (decl)) == REG
5479 || (GET_CODE (DECL_RTL (decl)) == MEM
5480 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5482 /* If longjmp doesn't restore the registers,
5483 don't put anything in them. */
5484 #ifdef NON_SAVING_SETJMP
5488 ! DECL_REGISTER (decl)))
5489 put_var_into_stack (decl);
5492 /* Return the context-pointer register corresponding to DECL,
5493 or 0 if it does not need one. */
5496 lookup_static_chain (decl)
5499 tree context = decl_function_context (decl);
5503 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5506 /* We treat inline_function_decl as an alias for the current function
5507 because that is the inline function whose vars, types, etc.
5508 are being merged into the current function.
5509 See expand_inline_function. */
5510 if (context == current_function_decl || context == inline_function_decl)
5511 return virtual_stack_vars_rtx;
5513 for (link = context_display; link; link = TREE_CHAIN (link))
5514 if (TREE_PURPOSE (link) == context)
5515 return RTL_EXPR_RTL (TREE_VALUE (link));
5520 /* Convert a stack slot address ADDR for variable VAR
5521 (from a containing function)
5522 into an address valid in this function (using a static chain). */
5525 fix_lexical_addr (addr, var)
5530 HOST_WIDE_INT displacement;
5531 tree context = decl_function_context (var);
5532 struct function *fp;
5535 /* If this is the present function, we need not do anything. */
5536 if (context == current_function_decl || context == inline_function_decl)
5539 for (fp = outer_function_chain; fp; fp = fp->next)
5540 if (fp->decl == context)
5546 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5547 addr = XEXP (XEXP (addr, 0), 0);
5549 /* Decode given address as base reg plus displacement. */
5550 if (GET_CODE (addr) == REG)
5551 basereg = addr, displacement = 0;
5552 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5553 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5557 /* We accept vars reached via the containing function's
5558 incoming arg pointer and via its stack variables pointer. */
5559 if (basereg == fp->internal_arg_pointer)
5561 /* If reached via arg pointer, get the arg pointer value
5562 out of that function's stack frame.
5564 There are two cases: If a separate ap is needed, allocate a
5565 slot in the outer function for it and dereference it that way.
5566 This is correct even if the real ap is actually a pseudo.
5567 Otherwise, just adjust the offset from the frame pointer to
5570 #ifdef NEED_SEPARATE_AP
5573 if (fp->x_arg_pointer_save_area == 0)
5574 fp->x_arg_pointer_save_area
5575 = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, fp);
5577 addr = fix_lexical_addr (XEXP (fp->x_arg_pointer_save_area, 0), var);
5578 addr = memory_address (Pmode, addr);
5580 base = gen_rtx_MEM (Pmode, addr);
5581 MEM_ALIAS_SET (base) = get_frame_alias_set ();
5582 base = copy_to_reg (base);
5584 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5585 base = lookup_static_chain (var);
5589 else if (basereg == virtual_stack_vars_rtx)
5591 /* This is the same code as lookup_static_chain, duplicated here to
5592 avoid an extra call to decl_function_context. */
5595 for (link = context_display; link; link = TREE_CHAIN (link))
5596 if (TREE_PURPOSE (link) == context)
5598 base = RTL_EXPR_RTL (TREE_VALUE (link));
5606 /* Use same offset, relative to appropriate static chain or argument
5608 return plus_constant (base, displacement);
5611 /* Return the address of the trampoline for entering nested fn FUNCTION.
5612 If necessary, allocate a trampoline (in the stack frame)
5613 and emit rtl to initialize its contents (at entry to this function). */
5616 trampoline_address (function)
5622 struct function *fp;
5625 /* Find an existing trampoline and return it. */
5626 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5627 if (TREE_PURPOSE (link) == function)
5629 adjust_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5631 for (fp = outer_function_chain; fp; fp = fp->next)
5632 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5633 if (TREE_PURPOSE (link) == function)
5635 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5637 return adjust_trampoline_addr (tramp);
5640 /* None exists; we must make one. */
5642 /* Find the `struct function' for the function containing FUNCTION. */
5644 fn_context = decl_function_context (function);
5645 if (fn_context != current_function_decl
5646 && fn_context != inline_function_decl)
5647 for (fp = outer_function_chain; fp; fp = fp->next)
5648 if (fp->decl == fn_context)
5651 /* Allocate run-time space for this trampoline
5652 (usually in the defining function's stack frame). */
5653 #ifdef ALLOCATE_TRAMPOLINE
5654 tramp = ALLOCATE_TRAMPOLINE (fp);
5656 /* If rounding needed, allocate extra space
5657 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5658 #ifdef TRAMPOLINE_ALIGNMENT
5659 #define TRAMPOLINE_REAL_SIZE \
5660 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5662 #define TRAMPOLINE_REAL_SIZE (TRAMPOLINE_SIZE)
5664 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5668 /* Record the trampoline for reuse and note it for later initialization
5669 by expand_function_end. */
5672 rtlexp = make_node (RTL_EXPR);
5673 RTL_EXPR_RTL (rtlexp) = tramp;
5674 fp->x_trampoline_list = tree_cons (function, rtlexp,
5675 fp->x_trampoline_list);
5679 /* Make the RTL_EXPR node temporary, not momentary, so that the
5680 trampoline_list doesn't become garbage. */
5681 rtlexp = make_node (RTL_EXPR);
5683 RTL_EXPR_RTL (rtlexp) = tramp;
5684 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5687 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5688 return adjust_trampoline_addr (tramp);
5691 /* Given a trampoline address,
5692 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5695 round_trampoline_addr (tramp)
5698 #ifdef TRAMPOLINE_ALIGNMENT
5699 /* Round address up to desired boundary. */
5700 rtx temp = gen_reg_rtx (Pmode);
5701 temp = expand_binop (Pmode, add_optab, tramp,
5702 GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1),
5703 temp, 0, OPTAB_LIB_WIDEN);
5704 tramp = expand_binop (Pmode, and_optab, temp,
5705 GEN_INT (-TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT),
5706 temp, 0, OPTAB_LIB_WIDEN);
5711 /* Given a trampoline address, round it then apply any
5712 platform-specific adjustments so that the result can be used for a
5716 adjust_trampoline_addr (tramp)
5719 tramp = round_trampoline_addr (tramp);
5720 #ifdef TRAMPOLINE_ADJUST_ADDRESS
5721 TRAMPOLINE_ADJUST_ADDRESS (tramp);
5726 /* Put all this function's BLOCK nodes including those that are chained
5727 onto the first block into a vector, and return it.
5728 Also store in each NOTE for the beginning or end of a block
5729 the index of that block in the vector.
5730 The arguments are BLOCK, the chain of top-level blocks of the function,
5731 and INSNS, the insn chain of the function. */
5737 tree *block_vector, *last_block_vector;
5739 tree block = DECL_INITIAL (current_function_decl);
5744 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5745 depth-first order. */
5746 block_vector = get_block_vector (block, &n_blocks);
5747 block_stack = (tree *) xmalloc (n_blocks * sizeof (tree));
5749 last_block_vector = identify_blocks_1 (get_insns (),
5751 block_vector + n_blocks,
5754 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5755 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5756 if (0 && last_block_vector != block_vector + n_blocks)
5759 free (block_vector);
5763 /* Subroutine of identify_blocks. Do the block substitution on the
5764 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
5766 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5767 BLOCK_VECTOR is incremented for each block seen. */
5770 identify_blocks_1 (insns, block_vector, end_block_vector, orig_block_stack)
5773 tree *end_block_vector;
5774 tree *orig_block_stack;
5777 tree *block_stack = orig_block_stack;
5779 for (insn = insns; insn; insn = NEXT_INSN (insn))
5781 if (GET_CODE (insn) == NOTE)
5783 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5787 /* If there are more block notes than BLOCKs, something
5789 if (block_vector == end_block_vector)
5792 b = *block_vector++;
5793 NOTE_BLOCK (insn) = b;
5796 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5798 /* If there are more NOTE_INSN_BLOCK_ENDs than
5799 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
5800 if (block_stack == orig_block_stack)
5803 NOTE_BLOCK (insn) = *--block_stack;
5806 else if (GET_CODE (insn) == CALL_INSN
5807 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5809 rtx cp = PATTERN (insn);
5811 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
5812 end_block_vector, block_stack);
5814 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
5815 end_block_vector, block_stack);
5817 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
5818 end_block_vector, block_stack);
5822 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
5823 something is badly wrong. */
5824 if (block_stack != orig_block_stack)
5827 return block_vector;
5830 /* Identify BLOCKs referenced by more than one
5831 NOTE_INSN_BLOCK_{BEG,END}, and create duplicate blocks. */
5836 tree block = DECL_INITIAL (current_function_decl);
5837 varray_type block_stack;
5839 if (block == NULL_TREE)
5842 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
5844 /* Prune the old trees away, so that they don't get in the way. */
5845 BLOCK_SUBBLOCKS (block) = NULL_TREE;
5846 BLOCK_CHAIN (block) = NULL_TREE;
5848 reorder_blocks_0 (get_insns ());
5849 reorder_blocks_1 (get_insns (), block, &block_stack);
5851 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
5853 VARRAY_FREE (block_stack);
5856 /* Helper function for reorder_blocks. Process the insn chain beginning
5857 at INSNS. Recurse for CALL_PLACEHOLDER insns. */
5860 reorder_blocks_0 (insns)
5865 for (insn = insns; insn; insn = NEXT_INSN (insn))
5867 if (GET_CODE (insn) == NOTE)
5869 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5871 tree block = NOTE_BLOCK (insn);
5872 TREE_ASM_WRITTEN (block) = 0;
5875 else if (GET_CODE (insn) == CALL_INSN
5876 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5878 rtx cp = PATTERN (insn);
5879 reorder_blocks_0 (XEXP (cp, 0));
5881 reorder_blocks_0 (XEXP (cp, 1));
5883 reorder_blocks_0 (XEXP (cp, 2));
5889 reorder_blocks_1 (insns, current_block, p_block_stack)
5892 varray_type *p_block_stack;
5896 for (insn = insns; insn; insn = NEXT_INSN (insn))
5898 if (GET_CODE (insn) == NOTE)
5900 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5902 tree block = NOTE_BLOCK (insn);
5903 /* If we have seen this block before, copy it. */
5904 if (TREE_ASM_WRITTEN (block))
5906 block = copy_node (block);
5907 NOTE_BLOCK (insn) = block;
5909 BLOCK_SUBBLOCKS (block) = 0;
5910 TREE_ASM_WRITTEN (block) = 1;
5911 BLOCK_SUPERCONTEXT (block) = current_block;
5912 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
5913 BLOCK_SUBBLOCKS (current_block) = block;
5914 current_block = block;
5915 VARRAY_PUSH_TREE (*p_block_stack, block);
5917 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5919 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
5920 VARRAY_POP (*p_block_stack);
5921 BLOCK_SUBBLOCKS (current_block)
5922 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5923 current_block = BLOCK_SUPERCONTEXT (current_block);
5926 else if (GET_CODE (insn) == CALL_INSN
5927 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5929 rtx cp = PATTERN (insn);
5930 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
5932 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
5934 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
5939 /* Reverse the order of elements in the chain T of blocks,
5940 and return the new head of the chain (old last element). */
5946 register tree prev = 0, decl, next;
5947 for (decl = t; decl; decl = next)
5949 next = BLOCK_CHAIN (decl);
5950 BLOCK_CHAIN (decl) = prev;
5956 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
5957 non-NULL, list them all into VECTOR, in a depth-first preorder
5958 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
5962 all_blocks (block, vector)
5970 TREE_ASM_WRITTEN (block) = 0;
5972 /* Record this block. */
5974 vector[n_blocks] = block;
5978 /* Record the subblocks, and their subblocks... */
5979 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
5980 vector ? vector + n_blocks : 0);
5981 block = BLOCK_CHAIN (block);
5987 /* Return a vector containing all the blocks rooted at BLOCK. The
5988 number of elements in the vector is stored in N_BLOCKS_P. The
5989 vector is dynamically allocated; it is the caller's responsibility
5990 to call `free' on the pointer returned. */
5993 get_block_vector (block, n_blocks_p)
5999 *n_blocks_p = all_blocks (block, NULL);
6000 block_vector = (tree *) xmalloc (*n_blocks_p * sizeof (tree));
6001 all_blocks (block, block_vector);
6003 return block_vector;
6006 static int next_block_index = 2;
6008 /* Set BLOCK_NUMBER for all the blocks in FN. */
6018 /* For SDB and XCOFF debugging output, we start numbering the blocks
6019 from 1 within each function, rather than keeping a running
6021 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6022 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
6023 next_block_index = 1;
6026 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
6028 /* The top-level BLOCK isn't numbered at all. */
6029 for (i = 1; i < n_blocks; ++i)
6030 /* We number the blocks from two. */
6031 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
6033 free (block_vector);
6038 /* Allocate a function structure and reset its contents to the defaults. */
6040 prepare_function_start ()
6042 cfun = (struct function *) xcalloc (1, sizeof (struct function));
6044 init_stmt_for_function ();
6045 init_eh_for_function ();
6047 cse_not_expected = ! optimize;
6049 /* Caller save not needed yet. */
6050 caller_save_needed = 0;
6052 /* No stack slots have been made yet. */
6053 stack_slot_list = 0;
6055 current_function_has_nonlocal_label = 0;
6056 current_function_has_nonlocal_goto = 0;
6058 /* There is no stack slot for handling nonlocal gotos. */
6059 nonlocal_goto_handler_slots = 0;
6060 nonlocal_goto_stack_level = 0;
6062 /* No labels have been declared for nonlocal use. */
6063 nonlocal_labels = 0;
6064 nonlocal_goto_handler_labels = 0;
6066 /* No function calls so far in this function. */
6067 function_call_count = 0;
6069 /* No parm regs have been allocated.
6070 (This is important for output_inline_function.) */
6071 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
6073 /* Initialize the RTL mechanism. */
6076 /* Initialize the queue of pending postincrement and postdecrements,
6077 and some other info in expr.c. */
6080 /* We haven't done register allocation yet. */
6083 init_varasm_status (cfun);
6085 /* Clear out data used for inlining. */
6086 cfun->inlinable = 0;
6087 cfun->original_decl_initial = 0;
6088 cfun->original_arg_vector = 0;
6090 #ifdef STACK_BOUNDARY
6091 cfun->stack_alignment_needed = STACK_BOUNDARY;
6092 cfun->preferred_stack_boundary = STACK_BOUNDARY;
6094 cfun->stack_alignment_needed = 0;
6095 cfun->preferred_stack_boundary = 0;
6098 /* Set if a call to setjmp is seen. */
6099 current_function_calls_setjmp = 0;
6101 /* Set if a call to longjmp is seen. */
6102 current_function_calls_longjmp = 0;
6104 current_function_calls_alloca = 0;
6105 current_function_contains_functions = 0;
6106 current_function_is_leaf = 0;
6107 current_function_nothrow = 0;
6108 current_function_sp_is_unchanging = 0;
6109 current_function_uses_only_leaf_regs = 0;
6110 current_function_has_computed_jump = 0;
6111 current_function_is_thunk = 0;
6113 current_function_returns_pcc_struct = 0;
6114 current_function_returns_struct = 0;
6115 current_function_epilogue_delay_list = 0;
6116 current_function_uses_const_pool = 0;
6117 current_function_uses_pic_offset_table = 0;
6118 current_function_cannot_inline = 0;
6120 /* We have not yet needed to make a label to jump to for tail-recursion. */
6121 tail_recursion_label = 0;
6123 /* We haven't had a need to make a save area for ap yet. */
6124 arg_pointer_save_area = 0;
6126 /* No stack slots allocated yet. */
6129 /* No SAVE_EXPRs in this function yet. */
6132 /* No RTL_EXPRs in this function yet. */
6135 /* Set up to allocate temporaries. */
6138 /* Indicate that we need to distinguish between the return value of the
6139 present function and the return value of a function being called. */
6140 rtx_equal_function_value_matters = 1;
6142 /* Indicate that we have not instantiated virtual registers yet. */
6143 virtuals_instantiated = 0;
6145 /* Indicate that we want CONCATs now. */
6146 generating_concat_p = 1;
6148 /* Indicate we have no need of a frame pointer yet. */
6149 frame_pointer_needed = 0;
6151 /* By default assume not varargs or stdarg. */
6152 current_function_varargs = 0;
6153 current_function_stdarg = 0;
6155 /* We haven't made any trampolines for this function yet. */
6156 trampoline_list = 0;
6158 init_pending_stack_adjust ();
6159 inhibit_defer_pop = 0;
6161 current_function_outgoing_args_size = 0;
6163 if (init_lang_status)
6164 (*init_lang_status) (cfun);
6165 if (init_machine_status)
6166 (*init_machine_status) (cfun);
6169 /* Initialize the rtl expansion mechanism so that we can do simple things
6170 like generate sequences. This is used to provide a context during global
6171 initialization of some passes. */
6173 init_dummy_function_start ()
6175 prepare_function_start ();
6178 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6179 and initialize static variables for generating RTL for the statements
6183 init_function_start (subr, filename, line)
6185 const char *filename;
6188 prepare_function_start ();
6190 /* Remember this function for later. */
6191 cfun->next_global = all_functions;
6192 all_functions = cfun;
6194 current_function_name = (*decl_printable_name) (subr, 2);
6197 /* Nonzero if this is a nested function that uses a static chain. */
6199 current_function_needs_context
6200 = (decl_function_context (current_function_decl) != 0
6201 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
6203 /* Within function body, compute a type's size as soon it is laid out. */
6204 immediate_size_expand++;
6206 /* Prevent ever trying to delete the first instruction of a function.
6207 Also tell final how to output a linenum before the function prologue.
6208 Note linenums could be missing, e.g. when compiling a Java .class file. */
6210 emit_line_note (filename, line);
6212 /* Make sure first insn is a note even if we don't want linenums.
6213 This makes sure the first insn will never be deleted.
6214 Also, final expects a note to appear there. */
6215 emit_note (NULL, NOTE_INSN_DELETED);
6217 /* Set flags used by final.c. */
6218 if (aggregate_value_p (DECL_RESULT (subr)))
6220 #ifdef PCC_STATIC_STRUCT_RETURN
6221 current_function_returns_pcc_struct = 1;
6223 current_function_returns_struct = 1;
6226 /* Warn if this value is an aggregate type,
6227 regardless of which calling convention we are using for it. */
6228 if (warn_aggregate_return
6229 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6230 warning ("function returns an aggregate");
6232 current_function_returns_pointer
6233 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
6236 /* Make sure all values used by the optimization passes have sane
6239 init_function_for_compilation ()
6243 /* No prologue/epilogue insns yet. */
6244 VARRAY_GROW (prologue, 0);
6245 VARRAY_GROW (epilogue, 0);
6246 VARRAY_GROW (sibcall_epilogue, 0);
6249 /* Indicate that the current function uses extra args
6250 not explicitly mentioned in the argument list in any fashion. */
6255 current_function_varargs = 1;
6258 /* Expand a call to __main at the beginning of a possible main function. */
6260 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6261 #undef HAS_INIT_SECTION
6262 #define HAS_INIT_SECTION
6266 expand_main_function ()
6268 #if !defined (HAS_INIT_SECTION)
6269 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, NAME__MAIN), 0,
6271 #endif /* not HAS_INIT_SECTION */
6274 extern struct obstack permanent_obstack;
6276 /* The PENDING_SIZES represent the sizes of variable-sized types.
6277 Create RTL for the various sizes now (using temporary variables),
6278 so that we can refer to the sizes from the RTL we are generating
6279 for the current function. The PENDING_SIZES are a TREE_LIST. The
6280 TREE_VALUE of each node is a SAVE_EXPR. */
6283 expand_pending_sizes (pending_sizes)
6288 /* Evaluate now the sizes of any types declared among the arguments. */
6289 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
6291 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode,
6292 EXPAND_MEMORY_USE_BAD);
6293 /* Flush the queue in case this parameter declaration has
6299 /* Start the RTL for a new function, and set variables used for
6301 SUBR is the FUNCTION_DECL node.
6302 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6303 the function's parameters, which must be run at any return statement. */
6306 expand_function_start (subr, parms_have_cleanups)
6308 int parms_have_cleanups;
6311 rtx last_ptr = NULL_RTX;
6313 /* Make sure volatile mem refs aren't considered
6314 valid operands of arithmetic insns. */
6315 init_recog_no_volatile ();
6317 /* Set this before generating any memory accesses. */
6318 current_function_check_memory_usage
6319 = (flag_check_memory_usage
6320 && ! DECL_NO_CHECK_MEMORY_USAGE (current_function_decl));
6322 current_function_instrument_entry_exit
6323 = (flag_instrument_function_entry_exit
6324 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6326 current_function_limit_stack
6327 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6329 /* If function gets a static chain arg, store it in the stack frame.
6330 Do this first, so it gets the first stack slot offset. */
6331 if (current_function_needs_context)
6333 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
6335 /* Delay copying static chain if it is not a register to avoid
6336 conflicts with regs used for parameters. */
6337 if (! SMALL_REGISTER_CLASSES
6338 || GET_CODE (static_chain_incoming_rtx) == REG)
6339 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6342 /* If the parameters of this function need cleaning up, get a label
6343 for the beginning of the code which executes those cleanups. This must
6344 be done before doing anything with return_label. */
6345 if (parms_have_cleanups)
6346 cleanup_label = gen_label_rtx ();
6350 /* Make the label for return statements to jump to. Do not special
6351 case machines with special return instructions -- they will be
6352 handled later during jump, ifcvt, or epilogue creation. */
6353 return_label = gen_label_rtx ();
6355 /* Initialize rtx used to return the value. */
6356 /* Do this before assign_parms so that we copy the struct value address
6357 before any library calls that assign parms might generate. */
6359 /* Decide whether to return the value in memory or in a register. */
6360 if (aggregate_value_p (DECL_RESULT (subr)))
6362 /* Returning something that won't go in a register. */
6363 register rtx value_address = 0;
6365 #ifdef PCC_STATIC_STRUCT_RETURN
6366 if (current_function_returns_pcc_struct)
6368 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6369 value_address = assemble_static_space (size);
6374 /* Expect to be passed the address of a place to store the value.
6375 If it is passed as an argument, assign_parms will take care of
6377 if (struct_value_incoming_rtx)
6379 value_address = gen_reg_rtx (Pmode);
6380 emit_move_insn (value_address, struct_value_incoming_rtx);
6385 SET_DECL_RTL (DECL_RESULT (subr),
6386 gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)),
6388 set_mem_attributes (DECL_RTL (DECL_RESULT (subr)),
6389 DECL_RESULT (subr), 1);
6392 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6393 /* If return mode is void, this decl rtl should not be used. */
6394 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
6397 /* Compute the return values into a pseudo reg, which we will copy
6398 into the true return register after the cleanups are done. */
6400 /* In order to figure out what mode to use for the pseudo, we
6401 figure out what the mode of the eventual return register will
6402 actually be, and use that. */
6404 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
6407 /* Structures that are returned in registers are not aggregate_value_p,
6408 so we may see a PARALLEL. Don't play pseudo games with this. */
6409 if (! REG_P (hard_reg))
6410 SET_DECL_RTL (DECL_RESULT (subr), hard_reg);
6413 /* Create the pseudo. */
6414 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg)));
6416 /* Needed because we may need to move this to memory
6417 in case it's a named return value whose address is taken. */
6418 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6422 /* Initialize rtx for parameters and local variables.
6423 In some cases this requires emitting insns. */
6425 assign_parms (subr);
6427 /* Copy the static chain now if it wasn't a register. The delay is to
6428 avoid conflicts with the parameter passing registers. */
6430 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6431 if (GET_CODE (static_chain_incoming_rtx) != REG)
6432 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6434 /* The following was moved from init_function_start.
6435 The move is supposed to make sdb output more accurate. */
6436 /* Indicate the beginning of the function body,
6437 as opposed to parm setup. */
6438 emit_note (NULL, NOTE_INSN_FUNCTION_BEG);
6440 if (GET_CODE (get_last_insn ()) != NOTE)
6441 emit_note (NULL, NOTE_INSN_DELETED);
6442 parm_birth_insn = get_last_insn ();
6444 context_display = 0;
6445 if (current_function_needs_context)
6447 /* Fetch static chain values for containing functions. */
6448 tem = decl_function_context (current_function_decl);
6449 /* Copy the static chain pointer into a pseudo. If we have
6450 small register classes, copy the value from memory if
6451 static_chain_incoming_rtx is a REG. */
6454 /* If the static chain originally came in a register, put it back
6455 there, then move it out in the next insn. The reason for
6456 this peculiar code is to satisfy function integration. */
6457 if (SMALL_REGISTER_CLASSES
6458 && GET_CODE (static_chain_incoming_rtx) == REG)
6459 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6460 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6465 tree rtlexp = make_node (RTL_EXPR);
6467 RTL_EXPR_RTL (rtlexp) = last_ptr;
6468 context_display = tree_cons (tem, rtlexp, context_display);
6469 tem = decl_function_context (tem);
6472 /* Chain thru stack frames, assuming pointer to next lexical frame
6473 is found at the place we always store it. */
6474 #ifdef FRAME_GROWS_DOWNWARD
6475 last_ptr = plus_constant (last_ptr,
6476 -(HOST_WIDE_INT) GET_MODE_SIZE (Pmode));
6478 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr));
6479 MEM_ALIAS_SET (last_ptr) = get_frame_alias_set ();
6480 last_ptr = copy_to_reg (last_ptr);
6482 /* If we are not optimizing, ensure that we know that this
6483 piece of context is live over the entire function. */
6485 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6490 if (current_function_instrument_entry_exit)
6492 rtx fun = DECL_RTL (current_function_decl);
6493 if (GET_CODE (fun) == MEM)
6494 fun = XEXP (fun, 0);
6497 emit_library_call (profile_function_entry_libfunc, 0, VOIDmode, 2,
6499 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6501 hard_frame_pointer_rtx),
6507 PROFILE_HOOK (profile_label_no);
6510 /* After the display initializations is where the tail-recursion label
6511 should go, if we end up needing one. Ensure we have a NOTE here
6512 since some things (like trampolines) get placed before this. */
6513 tail_recursion_reentry = emit_note (NULL, NOTE_INSN_DELETED);
6515 /* Evaluate now the sizes of any types declared among the arguments. */
6516 expand_pending_sizes (nreverse (get_pending_sizes ()));
6518 /* Make sure there is a line number after the function entry setup code. */
6519 force_next_line_note ();
6522 /* Undo the effects of init_dummy_function_start. */
6524 expand_dummy_function_end ()
6526 /* End any sequences that failed to be closed due to syntax errors. */
6527 while (in_sequence_p ())
6530 /* Outside function body, can't compute type's actual size
6531 until next function's body starts. */
6533 free_after_parsing (cfun);
6534 free_after_compilation (cfun);
6539 /* Call DOIT for each hard register used as a return value from
6540 the current function. */
6543 diddle_return_value (doit, arg)
6544 void (*doit) PARAMS ((rtx, void *));
6547 rtx outgoing = current_function_return_rtx;
6552 if (GET_CODE (outgoing) == REG)
6553 (*doit) (outgoing, arg);
6554 else if (GET_CODE (outgoing) == PARALLEL)
6558 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6560 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6562 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6569 do_clobber_return_reg (reg, arg)
6571 void *arg ATTRIBUTE_UNUSED;
6573 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6577 clobber_return_register ()
6579 diddle_return_value (do_clobber_return_reg, NULL);
6581 /* In case we do use pseudo to return value, clobber it too. */
6582 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6584 tree decl_result = DECL_RESULT (current_function_decl);
6585 rtx decl_rtl = DECL_RTL (decl_result);
6586 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
6588 do_clobber_return_reg (decl_rtl, NULL);
6594 do_use_return_reg (reg, arg)
6596 void *arg ATTRIBUTE_UNUSED;
6598 emit_insn (gen_rtx_USE (VOIDmode, reg));
6602 use_return_register ()
6604 diddle_return_value (do_use_return_reg, NULL);
6607 /* Generate RTL for the end of the current function.
6608 FILENAME and LINE are the current position in the source file.
6610 It is up to language-specific callers to do cleanups for parameters--
6611 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
6614 expand_function_end (filename, line, end_bindings)
6615 const char *filename;
6622 #ifdef TRAMPOLINE_TEMPLATE
6623 static rtx initial_trampoline;
6626 finish_expr_for_function ();
6628 #ifdef NON_SAVING_SETJMP
6629 /* Don't put any variables in registers if we call setjmp
6630 on a machine that fails to restore the registers. */
6631 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6633 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6634 setjmp_protect (DECL_INITIAL (current_function_decl));
6636 setjmp_protect_args ();
6640 /* Save the argument pointer if a save area was made for it. */
6641 if (arg_pointer_save_area)
6643 /* arg_pointer_save_area may not be a valid memory address, so we
6644 have to check it and fix it if necessary. */
6647 emit_move_insn (validize_mem (arg_pointer_save_area),
6648 virtual_incoming_args_rtx);
6649 seq = gen_sequence ();
6651 emit_insn_before (seq, tail_recursion_reentry);
6654 /* Initialize any trampolines required by this function. */
6655 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6657 tree function = TREE_PURPOSE (link);
6658 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6659 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6660 #ifdef TRAMPOLINE_TEMPLATE
6665 #ifdef TRAMPOLINE_TEMPLATE
6666 /* First make sure this compilation has a template for
6667 initializing trampolines. */
6668 if (initial_trampoline == 0)
6671 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6673 ggc_add_rtx_root (&initial_trampoline, 1);
6677 /* Generate insns to initialize the trampoline. */
6679 tramp = round_trampoline_addr (XEXP (tramp, 0));
6680 #ifdef TRAMPOLINE_TEMPLATE
6681 blktramp = change_address (initial_trampoline, BLKmode, tramp);
6682 emit_block_move (blktramp, initial_trampoline,
6683 GEN_INT (TRAMPOLINE_SIZE),
6684 TRAMPOLINE_ALIGNMENT);
6686 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6690 /* Put those insns at entry to the containing function (this one). */
6691 emit_insns_before (seq, tail_recursion_reentry);
6694 /* If we are doing stack checking and this function makes calls,
6695 do a stack probe at the start of the function to ensure we have enough
6696 space for another stack frame. */
6697 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6701 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6702 if (GET_CODE (insn) == CALL_INSN)
6705 probe_stack_range (STACK_CHECK_PROTECT,
6706 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6709 emit_insns_before (seq, tail_recursion_reentry);
6714 /* Warn about unused parms if extra warnings were specified. */
6715 /* Either ``-W -Wunused'' or ``-Wunused-parameter'' enables this
6716 warning. WARN_UNUSED_PARAMETER is negative when set by
6718 if (warn_unused_parameter > 0
6719 || (warn_unused_parameter < 0 && extra_warnings))
6723 for (decl = DECL_ARGUMENTS (current_function_decl);
6724 decl; decl = TREE_CHAIN (decl))
6725 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6726 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6727 warning_with_decl (decl, "unused parameter `%s'");
6730 /* Delete handlers for nonlocal gotos if nothing uses them. */
6731 if (nonlocal_goto_handler_slots != 0
6732 && ! current_function_has_nonlocal_label)
6735 /* End any sequences that failed to be closed due to syntax errors. */
6736 while (in_sequence_p ())
6739 /* Outside function body, can't compute type's actual size
6740 until next function's body starts. */
6741 immediate_size_expand--;
6743 clear_pending_stack_adjust ();
6744 do_pending_stack_adjust ();
6746 /* Mark the end of the function body.
6747 If control reaches this insn, the function can drop through
6748 without returning a value. */
6749 emit_note (NULL, NOTE_INSN_FUNCTION_END);
6751 /* Must mark the last line number note in the function, so that the test
6752 coverage code can avoid counting the last line twice. This just tells
6753 the code to ignore the immediately following line note, since there
6754 already exists a copy of this note somewhere above. This line number
6755 note is still needed for debugging though, so we can't delete it. */
6756 if (flag_test_coverage)
6757 emit_note (NULL, NOTE_INSN_REPEATED_LINE_NUMBER);
6759 /* Output a linenumber for the end of the function.
6760 SDB depends on this. */
6761 emit_line_note_force (filename, line);
6763 /* Before the return label (if any), clobber the return
6764 registers so that they are not propogated live to the rest of
6765 the function. This can only happen with functions that drop
6766 through; if there had been a return statement, there would
6767 have either been a return rtx, or a jump to the return label.
6769 We delay actual code generation after the current_function_value_rtx
6771 clobber_after = get_last_insn ();
6773 /* Output the label for the actual return from the function,
6774 if one is expected. This happens either because a function epilogue
6775 is used instead of a return instruction, or because a return was done
6776 with a goto in order to run local cleanups, or because of pcc-style
6777 structure returning. */
6779 emit_label (return_label);
6781 /* C++ uses this. */
6783 expand_end_bindings (0, 0, 0);
6785 if (current_function_instrument_entry_exit)
6787 rtx fun = DECL_RTL (current_function_decl);
6788 if (GET_CODE (fun) == MEM)
6789 fun = XEXP (fun, 0);
6792 emit_library_call (profile_function_exit_libfunc, 0, VOIDmode, 2,
6794 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6796 hard_frame_pointer_rtx),
6800 /* Let except.c know where it should emit the call to unregister
6801 the function context for sjlj exceptions. */
6802 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
6803 sjlj_emit_function_exit_after (get_last_insn ());
6805 /* If we had calls to alloca, and this machine needs
6806 an accurate stack pointer to exit the function,
6807 insert some code to save and restore the stack pointer. */
6808 #ifdef EXIT_IGNORE_STACK
6809 if (! EXIT_IGNORE_STACK)
6811 if (current_function_calls_alloca)
6815 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
6816 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
6819 /* If scalar return value was computed in a pseudo-reg, or was a named
6820 return value that got dumped to the stack, copy that to the hard
6822 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6824 tree decl_result = DECL_RESULT (current_function_decl);
6825 rtx decl_rtl = DECL_RTL (decl_result);
6827 if (REG_P (decl_rtl)
6828 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
6829 : DECL_REGISTER (decl_result))
6833 #ifdef FUNCTION_OUTGOING_VALUE
6834 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
6835 current_function_decl);
6837 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
6838 current_function_decl);
6840 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
6842 /* If this is a BLKmode structure being returned in registers,
6843 then use the mode computed in expand_return. Note that if
6844 decl_rtl is memory, then its mode may have been changed,
6845 but that current_function_return_rtx has not. */
6846 if (GET_MODE (real_decl_rtl) == BLKmode)
6847 PUT_MODE (real_decl_rtl, GET_MODE (current_function_return_rtx));
6849 /* If a named return value dumped decl_return to memory, then
6850 we may need to re-do the PROMOTE_MODE signed/unsigned
6852 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
6854 int unsignedp = TREE_UNSIGNED (TREE_TYPE (decl_result));
6856 #ifdef PROMOTE_FUNCTION_RETURN
6857 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
6861 convert_move (real_decl_rtl, decl_rtl, unsignedp);
6863 else if (GET_CODE (real_decl_rtl) == PARALLEL)
6864 emit_group_load (real_decl_rtl, decl_rtl,
6865 int_size_in_bytes (TREE_TYPE (decl_result)),
6866 TYPE_ALIGN (TREE_TYPE (decl_result)));
6868 emit_move_insn (real_decl_rtl, decl_rtl);
6870 /* The delay slot scheduler assumes that current_function_return_rtx
6871 holds the hard register containing the return value, not a
6872 temporary pseudo. */
6873 current_function_return_rtx = real_decl_rtl;
6877 /* If returning a structure, arrange to return the address of the value
6878 in a place where debuggers expect to find it.
6880 If returning a structure PCC style,
6881 the caller also depends on this value.
6882 And current_function_returns_pcc_struct is not necessarily set. */
6883 if (current_function_returns_struct
6884 || current_function_returns_pcc_struct)
6887 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
6888 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
6889 #ifdef FUNCTION_OUTGOING_VALUE
6891 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
6892 current_function_decl);
6895 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
6898 /* Mark this as a function return value so integrate will delete the
6899 assignment and USE below when inlining this function. */
6900 REG_FUNCTION_VALUE_P (outgoing) = 1;
6902 #ifdef POINTERS_EXTEND_UNSIGNED
6903 /* The address may be ptr_mode and OUTGOING may be Pmode. */
6904 if (GET_MODE (outgoing) != GET_MODE (value_address))
6905 value_address = convert_memory_address (GET_MODE (outgoing),
6909 emit_move_insn (outgoing, value_address);
6911 /* Show return register used to hold result (in this case the address
6913 current_function_return_rtx = outgoing;
6916 /* If this is an implementation of throw, do what's necessary to
6917 communicate between __builtin_eh_return and the epilogue. */
6918 expand_eh_return ();
6920 /* Emit the actual code to clobber return register. */
6925 clobber_return_register ();
6926 seq = gen_sequence ();
6929 after = emit_insn_after (seq, clobber_after);
6931 if (clobber_after != after)
6932 cfun->x_clobber_return_insn = after;
6935 /* ??? This should no longer be necessary since stupid is no longer with
6936 us, but there are some parts of the compiler (eg reload_combine, and
6937 sh mach_dep_reorg) that still try and compute their own lifetime info
6938 instead of using the general framework. */
6939 use_return_register ();
6941 /* Output a return insn if we are using one.
6942 Otherwise, let the rtl chain end here, to drop through
6943 into the epilogue. */
6948 emit_jump_insn (gen_return ());
6953 /* Fix up any gotos that jumped out to the outermost
6954 binding level of the function.
6955 Must follow emitting RETURN_LABEL. */
6957 /* If you have any cleanups to do at this point,
6958 and they need to create temporary variables,
6959 then you will lose. */
6960 expand_fixups (get_insns ());
6963 /* Extend a vector that records the INSN_UIDs of INSNS (either a
6964 sequence or a single insn). */
6967 record_insns (insns, vecp)
6971 if (GET_CODE (insns) == SEQUENCE)
6973 int len = XVECLEN (insns, 0);
6974 int i = VARRAY_SIZE (*vecp);
6976 VARRAY_GROW (*vecp, i + len);
6979 VARRAY_INT (*vecp, i) = INSN_UID (XVECEXP (insns, 0, len));
6985 int i = VARRAY_SIZE (*vecp);
6986 VARRAY_GROW (*vecp, i + 1);
6987 VARRAY_INT (*vecp, i) = INSN_UID (insns);
6991 /* Determine how many INSN_UIDs in VEC are part of INSN. */
6994 contains (insn, vec)
7000 if (GET_CODE (insn) == INSN
7001 && GET_CODE (PATTERN (insn)) == SEQUENCE)
7004 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
7005 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7006 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
7012 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7013 if (INSN_UID (insn) == VARRAY_INT (vec, j))
7020 prologue_epilogue_contains (insn)
7023 if (contains (insn, prologue))
7025 if (contains (insn, epilogue))
7031 sibcall_epilogue_contains (insn)
7034 if (sibcall_epilogue)
7035 return contains (insn, sibcall_epilogue);
7040 /* Insert gen_return at the end of block BB. This also means updating
7041 block_for_insn appropriately. */
7044 emit_return_into_block (bb, line_note)
7050 p = NEXT_INSN (bb->end);
7051 end = emit_jump_insn_after (gen_return (), bb->end);
7053 emit_line_note_after (NOTE_SOURCE_FILE (line_note),
7054 NOTE_LINE_NUMBER (line_note), bb->end);
7058 set_block_for_insn (p, bb);
7065 #endif /* HAVE_return */
7067 #ifdef HAVE_epilogue
7069 /* Modify SEQ, a SEQUENCE that is part of the epilogue, to no modifications
7070 to the stack pointer. */
7073 keep_stack_depressed (seq)
7077 rtx sp_from_reg = 0;
7078 int sp_modified_unknown = 0;
7080 /* If the epilogue is just a single instruction, it's OK as is */
7082 if (GET_CODE (seq) != SEQUENCE)
7085 /* Scan all insns in SEQ looking for ones that modified the stack
7086 pointer. Record if it modified the stack pointer by copying it
7087 from the frame pointer or if it modified it in some other way.
7088 Then modify any subsequent stack pointer references to take that
7089 into account. We start by only allowing SP to be copied from a
7090 register (presumably FP) and then be subsequently referenced. */
7092 for (i = 0; i < XVECLEN (seq, 0); i++)
7094 rtx insn = XVECEXP (seq, 0, i);
7096 if (GET_RTX_CLASS (GET_CODE (insn)) != 'i')
7099 if (reg_set_p (stack_pointer_rtx, insn))
7101 rtx set = single_set (insn);
7103 /* If SP is set as a side-effect, we can't support this. */
7107 if (GET_CODE (SET_SRC (set)) == REG)
7108 sp_from_reg = SET_SRC (set);
7110 sp_modified_unknown = 1;
7112 /* Don't allow the SP modification to happen. */
7113 PUT_CODE (insn, NOTE);
7114 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
7115 NOTE_SOURCE_FILE (insn) = 0;
7117 else if (reg_referenced_p (stack_pointer_rtx, PATTERN (insn)))
7119 if (sp_modified_unknown)
7122 else if (sp_from_reg != 0)
7124 = replace_rtx (PATTERN (insn), stack_pointer_rtx, sp_from_reg);
7130 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7131 this into place with notes indicating where the prologue ends and where
7132 the epilogue begins. Update the basic block information when possible. */
7135 thread_prologue_and_epilogue_insns (f)
7136 rtx f ATTRIBUTE_UNUSED;
7141 #ifdef HAVE_prologue
7142 rtx prologue_end = NULL_RTX;
7144 #if defined (HAVE_epilogue) || defined(HAVE_return)
7145 rtx epilogue_end = NULL_RTX;
7148 #ifdef HAVE_prologue
7152 seq = gen_prologue ();
7155 /* Retain a map of the prologue insns. */
7156 if (GET_CODE (seq) != SEQUENCE)
7158 record_insns (seq, &prologue);
7159 prologue_end = emit_note (NULL, NOTE_INSN_PROLOGUE_END);
7161 seq = gen_sequence ();
7164 /* If optimization is off, and perhaps in an empty function,
7165 the entry block will have no successors. */
7166 if (ENTRY_BLOCK_PTR->succ)
7168 /* Can't deal with multiple successsors of the entry block. */
7169 if (ENTRY_BLOCK_PTR->succ->succ_next)
7172 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
7176 emit_insn_after (seq, f);
7180 /* If the exit block has no non-fake predecessors, we don't need
7182 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7183 if ((e->flags & EDGE_FAKE) == 0)
7189 if (optimize && HAVE_return)
7191 /* If we're allowed to generate a simple return instruction,
7192 then by definition we don't need a full epilogue. Examine
7193 the block that falls through to EXIT. If it does not
7194 contain any code, examine its predecessors and try to
7195 emit (conditional) return instructions. */
7201 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7202 if (e->flags & EDGE_FALLTHRU)
7208 /* Verify that there are no active instructions in the last block. */
7210 while (label && GET_CODE (label) != CODE_LABEL)
7212 if (active_insn_p (label))
7214 label = PREV_INSN (label);
7217 if (last->head == label && GET_CODE (label) == CODE_LABEL)
7219 rtx epilogue_line_note = NULL_RTX;
7221 /* Locate the line number associated with the closing brace,
7222 if we can find one. */
7223 for (seq = get_last_insn ();
7224 seq && ! active_insn_p (seq);
7225 seq = PREV_INSN (seq))
7226 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
7228 epilogue_line_note = seq;
7232 for (e = last->pred; e; e = e_next)
7234 basic_block bb = e->src;
7237 e_next = e->pred_next;
7238 if (bb == ENTRY_BLOCK_PTR)
7242 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
7245 /* If we have an unconditional jump, we can replace that
7246 with a simple return instruction. */
7247 if (simplejump_p (jump))
7249 emit_return_into_block (bb, epilogue_line_note);
7250 flow_delete_insn (jump);
7253 /* If we have a conditional jump, we can try to replace
7254 that with a conditional return instruction. */
7255 else if (condjump_p (jump))
7259 ret = SET_SRC (PATTERN (jump));
7260 if (GET_CODE (XEXP (ret, 1)) == LABEL_REF)
7261 loc = &XEXP (ret, 1);
7263 loc = &XEXP (ret, 2);
7264 ret = gen_rtx_RETURN (VOIDmode);
7266 if (! validate_change (jump, loc, ret, 0))
7268 if (JUMP_LABEL (jump))
7269 LABEL_NUSES (JUMP_LABEL (jump))--;
7271 /* If this block has only one successor, it both jumps
7272 and falls through to the fallthru block, so we can't
7274 if (bb->succ->succ_next == NULL)
7280 /* Fix up the CFG for the successful change we just made. */
7281 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7284 /* Emit a return insn for the exit fallthru block. Whether
7285 this is still reachable will be determined later. */
7287 emit_barrier_after (last->end);
7288 emit_return_into_block (last, epilogue_line_note);
7289 epilogue_end = last->end;
7294 #ifdef HAVE_epilogue
7297 /* Find the edge that falls through to EXIT. Other edges may exist
7298 due to RETURN instructions, but those don't need epilogues.
7299 There really shouldn't be a mixture -- either all should have
7300 been converted or none, however... */
7302 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7303 if (e->flags & EDGE_FALLTHRU)
7309 epilogue_end = emit_note (NULL, NOTE_INSN_EPILOGUE_BEG);
7311 seq = gen_epilogue ();
7313 /* If this function returns with the stack depressed, massage
7314 the epilogue to actually do that. */
7315 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7316 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7317 keep_stack_depressed (seq);
7319 emit_jump_insn (seq);
7321 /* Retain a map of the epilogue insns. */
7322 if (GET_CODE (seq) != SEQUENCE)
7324 record_insns (seq, &epilogue);
7326 seq = gen_sequence ();
7329 insert_insn_on_edge (seq, e);
7336 commit_edge_insertions ();
7338 #ifdef HAVE_sibcall_epilogue
7339 /* Emit sibling epilogues before any sibling call sites. */
7340 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7342 basic_block bb = e->src;
7347 if (GET_CODE (insn) != CALL_INSN
7348 || ! SIBLING_CALL_P (insn))
7352 seq = gen_sibcall_epilogue ();
7355 i = PREV_INSN (insn);
7356 newinsn = emit_insn_before (seq, insn);
7358 /* Update the UID to basic block map. */
7359 for (i = NEXT_INSN (i); i != insn; i = NEXT_INSN (i))
7360 set_block_for_insn (i, bb);
7362 /* Retain a map of the epilogue insns. Used in life analysis to
7363 avoid getting rid of sibcall epilogue insns. */
7364 record_insns (GET_CODE (seq) == SEQUENCE
7365 ? seq : newinsn, &sibcall_epilogue);
7369 #ifdef HAVE_prologue
7374 /* GDB handles `break f' by setting a breakpoint on the first
7375 line note after the prologue. Which means (1) that if
7376 there are line number notes before where we inserted the
7377 prologue we should move them, and (2) we should generate a
7378 note before the end of the first basic block, if there isn't
7381 ??? This behaviour is completely broken when dealing with
7382 multiple entry functions. We simply place the note always
7383 into first basic block and let alternate entry points
7387 for (insn = prologue_end; insn; insn = prev)
7389 prev = PREV_INSN (insn);
7390 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7392 /* Note that we cannot reorder the first insn in the
7393 chain, since rest_of_compilation relies on that
7394 remaining constant. */
7397 reorder_insns (insn, insn, prologue_end);
7401 /* Find the last line number note in the first block. */
7402 for (insn = BASIC_BLOCK (0)->end;
7403 insn != prologue_end && insn;
7404 insn = PREV_INSN (insn))
7405 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7408 /* If we didn't find one, make a copy of the first line number
7412 for (insn = next_active_insn (prologue_end);
7414 insn = PREV_INSN (insn))
7415 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7417 emit_line_note_after (NOTE_SOURCE_FILE (insn),
7418 NOTE_LINE_NUMBER (insn),
7425 #ifdef HAVE_epilogue
7430 /* Similarly, move any line notes that appear after the epilogue.
7431 There is no need, however, to be quite so anal about the existance
7433 for (insn = epilogue_end; insn; insn = next)
7435 next = NEXT_INSN (insn);
7436 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7437 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7443 /* Reposition the prologue-end and epilogue-begin notes after instruction
7444 scheduling and delayed branch scheduling. */
7447 reposition_prologue_and_epilogue_notes (f)
7448 rtx f ATTRIBUTE_UNUSED;
7450 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7453 if ((len = VARRAY_SIZE (prologue)) > 0)
7455 register rtx insn, note = 0;
7457 /* Scan from the beginning until we reach the last prologue insn.
7458 We apparently can't depend on basic_block_{head,end} after
7460 for (insn = f; len && insn; insn = NEXT_INSN (insn))
7462 if (GET_CODE (insn) == NOTE)
7464 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
7467 else if ((len -= contains (insn, prologue)) == 0)
7470 /* Find the prologue-end note if we haven't already, and
7471 move it to just after the last prologue insn. */
7474 for (note = insn; (note = NEXT_INSN (note));)
7475 if (GET_CODE (note) == NOTE
7476 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
7480 next = NEXT_INSN (note);
7482 /* Whether or not we can depend on BLOCK_HEAD,
7483 attempt to keep it up-to-date. */
7484 if (BLOCK_HEAD (0) == note)
7485 BLOCK_HEAD (0) = next;
7488 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
7489 if (GET_CODE (insn) == CODE_LABEL)
7490 insn = NEXT_INSN (insn);
7491 add_insn_after (note, insn);
7496 if ((len = VARRAY_SIZE (epilogue)) > 0)
7498 register rtx insn, note = 0;
7500 /* Scan from the end until we reach the first epilogue insn.
7501 We apparently can't depend on basic_block_{head,end} after
7503 for (insn = get_last_insn (); len && insn; insn = PREV_INSN (insn))
7505 if (GET_CODE (insn) == NOTE)
7507 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
7510 else if ((len -= contains (insn, epilogue)) == 0)
7512 /* Find the epilogue-begin note if we haven't already, and
7513 move it to just before the first epilogue insn. */
7516 for (note = insn; (note = PREV_INSN (note));)
7517 if (GET_CODE (note) == NOTE
7518 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
7522 /* Whether or not we can depend on BLOCK_HEAD,
7523 attempt to keep it up-to-date. */
7525 && BLOCK_HEAD (n_basic_blocks-1) == insn)
7526 BLOCK_HEAD (n_basic_blocks-1) = note;
7529 add_insn_before (note, insn);
7533 #endif /* HAVE_prologue or HAVE_epilogue */
7536 /* Mark T for GC. */
7540 struct temp_slot *t;
7544 ggc_mark_rtx (t->slot);
7545 ggc_mark_rtx (t->address);
7546 ggc_mark_tree (t->rtl_expr);
7547 ggc_mark_tree (t->type);
7553 /* Mark P for GC. */
7556 mark_function_status (p)
7565 ggc_mark_rtx (p->arg_offset_rtx);
7567 if (p->x_parm_reg_stack_loc)
7568 for (i = p->x_max_parm_reg, r = p->x_parm_reg_stack_loc;
7572 ggc_mark_rtx (p->return_rtx);
7573 ggc_mark_rtx (p->x_cleanup_label);
7574 ggc_mark_rtx (p->x_return_label);
7575 ggc_mark_rtx (p->x_save_expr_regs);
7576 ggc_mark_rtx (p->x_stack_slot_list);
7577 ggc_mark_rtx (p->x_parm_birth_insn);
7578 ggc_mark_rtx (p->x_tail_recursion_label);
7579 ggc_mark_rtx (p->x_tail_recursion_reentry);
7580 ggc_mark_rtx (p->internal_arg_pointer);
7581 ggc_mark_rtx (p->x_arg_pointer_save_area);
7582 ggc_mark_tree (p->x_rtl_expr_chain);
7583 ggc_mark_rtx (p->x_last_parm_insn);
7584 ggc_mark_tree (p->x_context_display);
7585 ggc_mark_tree (p->x_trampoline_list);
7586 ggc_mark_rtx (p->epilogue_delay_list);
7587 ggc_mark_rtx (p->x_clobber_return_insn);
7589 mark_temp_slot (p->x_temp_slots);
7592 struct var_refs_queue *q = p->fixup_var_refs_queue;
7595 ggc_mark_rtx (q->modified);
7600 ggc_mark_rtx (p->x_nonlocal_goto_handler_slots);
7601 ggc_mark_rtx (p->x_nonlocal_goto_handler_labels);
7602 ggc_mark_rtx (p->x_nonlocal_goto_stack_level);
7603 ggc_mark_tree (p->x_nonlocal_labels);
7605 mark_hard_reg_initial_vals (p);
7608 /* Mark the function chain ARG (which is really a struct function **)
7612 mark_function_chain (arg)
7615 struct function *f = *(struct function **) arg;
7617 for (; f; f = f->next_global)
7619 ggc_mark_tree (f->decl);
7621 mark_function_status (f);
7622 mark_eh_status (f->eh);
7623 mark_stmt_status (f->stmt);
7624 mark_expr_status (f->expr);
7625 mark_emit_status (f->emit);
7626 mark_varasm_status (f->varasm);
7628 if (mark_machine_status)
7629 (*mark_machine_status) (f);
7630 if (mark_lang_status)
7631 (*mark_lang_status) (f);
7633 if (f->original_arg_vector)
7634 ggc_mark_rtvec ((rtvec) f->original_arg_vector);
7635 if (f->original_decl_initial)
7636 ggc_mark_tree (f->original_decl_initial);
7640 /* Called once, at initialization, to initialize function.c. */
7643 init_function_once ()
7645 ggc_add_root (&all_functions, 1, sizeof all_functions,
7646 mark_function_chain);
7648 VARRAY_INT_INIT (prologue, 0, "prologue");
7649 VARRAY_INT_INIT (epilogue, 0, "epilogue");
7650 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");