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, 2002, 2003 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
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. */
43 #include "coretypes.h"
53 #include "hard-reg-set.h"
54 #include "insn-config.h"
57 #include "basic-block.h"
62 #include "integrate.h"
63 #include "langhooks.h"
65 #ifndef TRAMPOLINE_ALIGNMENT
66 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
69 #ifndef LOCAL_ALIGNMENT
70 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
73 #ifndef STACK_ALIGNMENT_NEEDED
74 #define STACK_ALIGNMENT_NEEDED 1
77 /* Some systems use __main in a way incompatible with its use in gcc, in these
78 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
79 give the same symbol without quotes for an alternative entry point. You
80 must define both, or neither. */
82 #define NAME__MAIN "__main"
85 /* Round a value to the lowest integer less than it that is a multiple of
86 the required alignment. Avoid using division in case the value is
87 negative. Assume the alignment is a power of two. */
88 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
90 /* Similar, but round to the next highest integer that meets the
92 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
94 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
95 during rtl generation. If they are different register numbers, this is
96 always true. It may also be true if
97 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
98 generation. See fix_lexical_addr for details. */
100 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
101 #define NEED_SEPARATE_AP
104 /* Nonzero if function being compiled doesn't contain any calls
105 (ignoring the prologue and epilogue). This is set prior to
106 local register allocation and is valid for the remaining
108 int current_function_is_leaf;
110 /* Nonzero if function being compiled doesn't contain any instructions
111 that can throw an exception. This is set prior to final. */
113 int current_function_nothrow;
115 /* Nonzero if function being compiled doesn't modify the stack pointer
116 (ignoring the prologue and epilogue). This is only valid after
117 life_analysis has run. */
118 int current_function_sp_is_unchanging;
120 /* Nonzero if the function being compiled is a leaf function which only
121 uses leaf registers. This is valid after reload (specifically after
122 sched2) and is useful only if the port defines LEAF_REGISTERS. */
123 int current_function_uses_only_leaf_regs;
125 /* Nonzero once virtual register instantiation has been done.
126 assign_stack_local uses frame_pointer_rtx when this is nonzero.
127 calls.c:emit_library_call_value_1 uses it to set up
128 post-instantiation libcalls. */
129 int virtuals_instantiated;
131 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
132 static GTY(()) int funcdef_no;
134 /* These variables hold pointers to functions to create and destroy
135 target specific, per-function data structures. */
136 struct machine_function * (*init_machine_status) PARAMS ((void));
138 /* The FUNCTION_DECL for an inline function currently being expanded. */
139 tree inline_function_decl;
141 /* The currently compiled function. */
142 struct function *cfun = 0;
144 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
145 static GTY(()) varray_type prologue;
146 static GTY(()) varray_type epilogue;
148 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
150 static GTY(()) varray_type sibcall_epilogue;
152 /* In order to evaluate some expressions, such as function calls returning
153 structures in memory, we need to temporarily allocate stack locations.
154 We record each allocated temporary in the following structure.
156 Associated with each temporary slot is a nesting level. When we pop up
157 one level, all temporaries associated with the previous level are freed.
158 Normally, all temporaries are freed after the execution of the statement
159 in which they were created. However, if we are inside a ({...}) grouping,
160 the result may be in a temporary and hence must be preserved. If the
161 result could be in a temporary, we preserve it if we can determine which
162 one it is in. If we cannot determine which temporary may contain the
163 result, all temporaries are preserved. A temporary is preserved by
164 pretending it was allocated at the previous nesting level.
166 Automatic variables are also assigned temporary slots, at the nesting
167 level where they are defined. They are marked a "kept" so that
168 free_temp_slots will not free them. */
170 struct temp_slot GTY(())
172 /* Points to next temporary slot. */
173 struct temp_slot *next;
174 /* The rtx to used to reference the slot. */
176 /* The rtx used to represent the address if not the address of the
177 slot above. May be an EXPR_LIST if multiple addresses exist. */
179 /* The alignment (in bits) of the slot. */
181 /* The size, in units, of the slot. */
183 /* The type of the object in the slot, or zero if it doesn't correspond
184 to a type. We use this to determine whether a slot can be reused.
185 It can be reused if objects of the type of the new slot will always
186 conflict with objects of the type of the old slot. */
188 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
190 /* Nonzero if this temporary is currently in use. */
192 /* Nonzero if this temporary has its address taken. */
194 /* Nesting level at which this slot is being used. */
196 /* Nonzero if this should survive a call to free_temp_slots. */
198 /* The offset of the slot from the frame_pointer, including extra space
199 for alignment. This info is for combine_temp_slots. */
200 HOST_WIDE_INT base_offset;
201 /* The size of the slot, including extra space for alignment. This
202 info is for combine_temp_slots. */
203 HOST_WIDE_INT full_size;
206 /* This structure is used to record MEMs or pseudos used to replace VAR, any
207 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
208 maintain this list in case two operands of an insn were required to match;
209 in that case we must ensure we use the same replacement. */
211 struct fixup_replacement GTY(())
215 struct fixup_replacement *next;
218 struct insns_for_mem_entry
222 /* These are the INSNs which reference the MEM. */
226 /* Forward declarations. */
228 static rtx assign_stack_local_1 PARAMS ((enum machine_mode, HOST_WIDE_INT,
229 int, struct function *));
230 static struct temp_slot *find_temp_slot_from_address PARAMS ((rtx));
231 static void put_reg_into_stack PARAMS ((struct function *, rtx, tree,
232 enum machine_mode, enum machine_mode,
233 int, unsigned int, int,
235 static void schedule_fixup_var_refs PARAMS ((struct function *, rtx, tree,
238 static void fixup_var_refs PARAMS ((rtx, enum machine_mode, int, rtx,
240 static struct fixup_replacement
241 *find_fixup_replacement PARAMS ((struct fixup_replacement **, rtx));
242 static void fixup_var_refs_insns PARAMS ((rtx, rtx, enum machine_mode,
244 static void fixup_var_refs_insns_with_hash
245 PARAMS ((htab_t, rtx,
246 enum machine_mode, int, rtx));
247 static void fixup_var_refs_insn PARAMS ((rtx, rtx, enum machine_mode,
249 static void fixup_var_refs_1 PARAMS ((rtx, enum machine_mode, rtx *, rtx,
250 struct fixup_replacement **, rtx));
251 static rtx fixup_memory_subreg PARAMS ((rtx, rtx, enum machine_mode, int));
252 static rtx walk_fixup_memory_subreg PARAMS ((rtx, rtx, enum machine_mode,
254 static rtx fixup_stack_1 PARAMS ((rtx, rtx));
255 static void optimize_bit_field PARAMS ((rtx, rtx, rtx *));
256 static void instantiate_decls PARAMS ((tree, int));
257 static void instantiate_decls_1 PARAMS ((tree, int));
258 static void instantiate_decl PARAMS ((rtx, HOST_WIDE_INT, int));
259 static rtx instantiate_new_reg PARAMS ((rtx, HOST_WIDE_INT *));
260 static int instantiate_virtual_regs_1 PARAMS ((rtx *, rtx, int));
261 static void delete_handlers PARAMS ((void));
262 static void pad_to_arg_alignment PARAMS ((struct args_size *, int,
263 struct args_size *));
264 static void pad_below PARAMS ((struct args_size *, enum machine_mode,
266 static rtx round_trampoline_addr PARAMS ((rtx));
267 static rtx adjust_trampoline_addr PARAMS ((rtx));
268 static tree *identify_blocks_1 PARAMS ((rtx, tree *, tree *, tree *));
269 static void reorder_blocks_0 PARAMS ((tree));
270 static void reorder_blocks_1 PARAMS ((rtx, tree, varray_type *));
271 static void reorder_fix_fragments PARAMS ((tree));
272 static tree blocks_nreverse PARAMS ((tree));
273 static int all_blocks PARAMS ((tree, tree *));
274 static tree *get_block_vector PARAMS ((tree, int *));
275 extern tree debug_find_var_in_block_tree PARAMS ((tree, tree));
276 /* We always define `record_insns' even if its not used so that we
277 can always export `prologue_epilogue_contains'. */
278 static void record_insns PARAMS ((rtx, varray_type *)) ATTRIBUTE_UNUSED;
279 static int contains PARAMS ((rtx, varray_type));
281 static void emit_return_into_block PARAMS ((basic_block, rtx));
283 static void put_addressof_into_stack PARAMS ((rtx, htab_t));
284 static bool purge_addressof_1 PARAMS ((rtx *, rtx, int, int,
286 static void purge_single_hard_subreg_set PARAMS ((rtx));
287 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
288 static rtx keep_stack_depressed PARAMS ((rtx));
290 static int is_addressof PARAMS ((rtx *, void *));
291 static hashval_t insns_for_mem_hash PARAMS ((const void *));
292 static int insns_for_mem_comp PARAMS ((const void *, const void *));
293 static int insns_for_mem_walk PARAMS ((rtx *, void *));
294 static void compute_insns_for_mem PARAMS ((rtx, rtx, htab_t));
295 static void prepare_function_start PARAMS ((void));
296 static void do_clobber_return_reg PARAMS ((rtx, void *));
297 static void do_use_return_reg PARAMS ((rtx, void *));
299 /* Pointer to chain of `struct function' for containing functions. */
300 static GTY(()) struct function *outer_function_chain;
302 /* Given a function decl for a containing function,
303 return the `struct function' for it. */
306 find_function_data (decl)
311 for (p = outer_function_chain; p; p = p->outer)
318 /* Save the current context for compilation of a nested function.
319 This is called from language-specific code. The caller should use
320 the enter_nested langhook to save any language-specific state,
321 since this function knows only about language-independent
325 push_function_context_to (context)
332 if (context == current_function_decl)
333 cfun->contains_functions = 1;
336 struct function *containing = find_function_data (context);
337 containing->contains_functions = 1;
342 init_dummy_function_start ();
345 p->outer = outer_function_chain;
346 outer_function_chain = p;
347 p->fixup_var_refs_queue = 0;
349 (*lang_hooks.function.enter_nested) (p);
355 push_function_context ()
357 push_function_context_to (current_function_decl);
360 /* Restore the last saved context, at the end of a nested function.
361 This function is called from language-specific code. */
364 pop_function_context_from (context)
365 tree context ATTRIBUTE_UNUSED;
367 struct function *p = outer_function_chain;
368 struct var_refs_queue *queue;
371 outer_function_chain = p->outer;
373 current_function_decl = p->decl;
376 restore_emit_status (p);
378 (*lang_hooks.function.leave_nested) (p);
380 /* Finish doing put_var_into_stack for any of our variables which became
381 addressable during the nested function. If only one entry has to be
382 fixed up, just do that one. Otherwise, first make a list of MEMs that
383 are not to be unshared. */
384 if (p->fixup_var_refs_queue == 0)
386 else if (p->fixup_var_refs_queue->next == 0)
387 fixup_var_refs (p->fixup_var_refs_queue->modified,
388 p->fixup_var_refs_queue->promoted_mode,
389 p->fixup_var_refs_queue->unsignedp,
390 p->fixup_var_refs_queue->modified, 0);
395 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
396 list = gen_rtx_EXPR_LIST (VOIDmode, queue->modified, list);
398 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
399 fixup_var_refs (queue->modified, queue->promoted_mode,
400 queue->unsignedp, list, 0);
404 p->fixup_var_refs_queue = 0;
406 /* Reset variables that have known state during rtx generation. */
407 rtx_equal_function_value_matters = 1;
408 virtuals_instantiated = 0;
409 generating_concat_p = 1;
413 pop_function_context ()
415 pop_function_context_from (current_function_decl);
418 /* Clear out all parts of the state in F that can safely be discarded
419 after the function has been parsed, but not compiled, to let
420 garbage collection reclaim the memory. */
423 free_after_parsing (f)
426 /* f->expr->forced_labels is used by code generation. */
427 /* f->emit->regno_reg_rtx is used by code generation. */
428 /* f->varasm is used by code generation. */
429 /* f->eh->eh_return_stub_label is used by code generation. */
431 (*lang_hooks.function.final) (f);
435 /* Clear out all parts of the state in F that can safely be discarded
436 after the function has been compiled, to let garbage collection
437 reclaim the memory. */
440 free_after_compilation (f)
449 f->x_temp_slots = NULL;
450 f->arg_offset_rtx = NULL;
451 f->return_rtx = NULL;
452 f->internal_arg_pointer = NULL;
453 f->x_nonlocal_labels = NULL;
454 f->x_nonlocal_goto_handler_slots = NULL;
455 f->x_nonlocal_goto_handler_labels = NULL;
456 f->x_nonlocal_goto_stack_level = NULL;
457 f->x_cleanup_label = NULL;
458 f->x_return_label = NULL;
459 f->computed_goto_common_label = NULL;
460 f->computed_goto_common_reg = NULL;
461 f->x_save_expr_regs = NULL;
462 f->x_stack_slot_list = NULL;
463 f->x_rtl_expr_chain = NULL;
464 f->x_tail_recursion_label = NULL;
465 f->x_tail_recursion_reentry = NULL;
466 f->x_arg_pointer_save_area = NULL;
467 f->x_clobber_return_insn = NULL;
468 f->x_context_display = NULL;
469 f->x_trampoline_list = NULL;
470 f->x_parm_birth_insn = NULL;
471 f->x_last_parm_insn = NULL;
472 f->x_parm_reg_stack_loc = NULL;
473 f->fixup_var_refs_queue = NULL;
474 f->original_arg_vector = NULL;
475 f->original_decl_initial = NULL;
476 f->inl_last_parm_insn = NULL;
477 f->epilogue_delay_list = NULL;
480 /* Allocate fixed slots in the stack frame of the current function. */
482 /* Return size needed for stack frame based on slots so far allocated in
484 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
485 the caller may have to do that. */
488 get_func_frame_size (f)
491 #ifdef FRAME_GROWS_DOWNWARD
492 return -f->x_frame_offset;
494 return f->x_frame_offset;
498 /* Return size needed for stack frame based on slots so far allocated.
499 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
500 the caller may have to do that. */
504 return get_func_frame_size (cfun);
507 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
508 with machine mode MODE.
510 ALIGN controls the amount of alignment for the address of the slot:
511 0 means according to MODE,
512 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
513 positive specifies alignment boundary in bits.
515 We do not round to stack_boundary here.
517 FUNCTION specifies the function to allocate in. */
520 assign_stack_local_1 (mode, size, align, function)
521 enum machine_mode mode;
524 struct function *function;
527 int bigend_correction = 0;
529 int frame_off, frame_alignment, frame_phase;
536 alignment = BIGGEST_ALIGNMENT;
538 alignment = GET_MODE_ALIGNMENT (mode);
540 /* Allow the target to (possibly) increase the alignment of this
542 type = (*lang_hooks.types.type_for_mode) (mode, 0);
544 alignment = LOCAL_ALIGNMENT (type, alignment);
546 alignment /= BITS_PER_UNIT;
548 else if (align == -1)
550 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
551 size = CEIL_ROUND (size, alignment);
554 alignment = align / BITS_PER_UNIT;
556 #ifdef FRAME_GROWS_DOWNWARD
557 function->x_frame_offset -= size;
560 /* Ignore alignment we can't do with expected alignment of the boundary. */
561 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
562 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
564 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
565 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
567 /* Calculate how many bytes the start of local variables is off from
569 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
570 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
571 frame_phase = frame_off ? frame_alignment - frame_off : 0;
573 /* Round the frame offset to the specified alignment. The default is
574 to always honor requests to align the stack but a port may choose to
575 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
576 if (STACK_ALIGNMENT_NEEDED
580 /* We must be careful here, since FRAME_OFFSET might be negative and
581 division with a negative dividend isn't as well defined as we might
582 like. So we instead assume that ALIGNMENT is a power of two and
583 use logical operations which are unambiguous. */
584 #ifdef FRAME_GROWS_DOWNWARD
585 function->x_frame_offset
586 = (FLOOR_ROUND (function->x_frame_offset - frame_phase, alignment)
589 function->x_frame_offset
590 = (CEIL_ROUND (function->x_frame_offset - frame_phase, alignment)
595 /* On a big-endian machine, if we are allocating more space than we will use,
596 use the least significant bytes of those that are allocated. */
597 if (BYTES_BIG_ENDIAN && mode != BLKmode)
598 bigend_correction = size - GET_MODE_SIZE (mode);
600 /* If we have already instantiated virtual registers, return the actual
601 address relative to the frame pointer. */
602 if (function == cfun && virtuals_instantiated)
603 addr = plus_constant (frame_pointer_rtx,
605 (frame_offset + bigend_correction
606 + STARTING_FRAME_OFFSET, Pmode));
608 addr = plus_constant (virtual_stack_vars_rtx,
610 (function->x_frame_offset + bigend_correction,
613 #ifndef FRAME_GROWS_DOWNWARD
614 function->x_frame_offset += size;
617 x = gen_rtx_MEM (mode, addr);
619 function->x_stack_slot_list
620 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
625 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
629 assign_stack_local (mode, size, align)
630 enum machine_mode mode;
634 return assign_stack_local_1 (mode, size, align, cfun);
637 /* Allocate a temporary stack slot and record it for possible later
640 MODE is the machine mode to be given to the returned rtx.
642 SIZE is the size in units of the space required. We do no rounding here
643 since assign_stack_local will do any required rounding.
645 KEEP is 1 if this slot is to be retained after a call to
646 free_temp_slots. Automatic variables for a block are allocated
647 with this flag. KEEP is 2 if we allocate a longer term temporary,
648 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
649 if we are to allocate something at an inner level to be treated as
650 a variable in the block (e.g., a SAVE_EXPR).
652 TYPE is the type that will be used for the stack slot. */
655 assign_stack_temp_for_type (mode, size, keep, type)
656 enum machine_mode mode;
662 struct temp_slot *p, *best_p = 0;
665 /* If SIZE is -1 it means that somebody tried to allocate a temporary
666 of a variable size. */
671 align = BIGGEST_ALIGNMENT;
673 align = GET_MODE_ALIGNMENT (mode);
676 type = (*lang_hooks.types.type_for_mode) (mode, 0);
679 align = LOCAL_ALIGNMENT (type, align);
681 /* Try to find an available, already-allocated temporary of the proper
682 mode which meets the size and alignment requirements. Choose the
683 smallest one with the closest alignment. */
684 for (p = temp_slots; p; p = p->next)
685 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
687 && objects_must_conflict_p (p->type, type)
688 && (best_p == 0 || best_p->size > p->size
689 || (best_p->size == p->size && best_p->align > p->align)))
691 if (p->align == align && p->size == size)
699 /* Make our best, if any, the one to use. */
702 /* If there are enough aligned bytes left over, make them into a new
703 temp_slot so that the extra bytes don't get wasted. Do this only
704 for BLKmode slots, so that we can be sure of the alignment. */
705 if (GET_MODE (best_p->slot) == BLKmode)
707 int alignment = best_p->align / BITS_PER_UNIT;
708 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
710 if (best_p->size - rounded_size >= alignment)
712 p = (struct temp_slot *) ggc_alloc (sizeof (struct temp_slot));
713 p->in_use = p->addr_taken = 0;
714 p->size = best_p->size - rounded_size;
715 p->base_offset = best_p->base_offset + rounded_size;
716 p->full_size = best_p->full_size - rounded_size;
717 p->slot = gen_rtx_MEM (BLKmode,
718 plus_constant (XEXP (best_p->slot, 0),
720 p->align = best_p->align;
723 p->type = best_p->type;
724 p->next = temp_slots;
727 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
730 best_p->size = rounded_size;
731 best_p->full_size = rounded_size;
738 /* If we still didn't find one, make a new temporary. */
741 HOST_WIDE_INT frame_offset_old = frame_offset;
743 p = (struct temp_slot *) ggc_alloc (sizeof (struct temp_slot));
745 /* We are passing an explicit alignment request to assign_stack_local.
746 One side effect of that is assign_stack_local will not round SIZE
747 to ensure the frame offset remains suitably aligned.
749 So for requests which depended on the rounding of SIZE, we go ahead
750 and round it now. We also make sure ALIGNMENT is at least
751 BIGGEST_ALIGNMENT. */
752 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
754 p->slot = assign_stack_local (mode,
756 ? CEIL_ROUND (size, (int) align / BITS_PER_UNIT)
762 /* The following slot size computation is necessary because we don't
763 know the actual size of the temporary slot until assign_stack_local
764 has performed all the frame alignment and size rounding for the
765 requested temporary. Note that extra space added for alignment
766 can be either above or below this stack slot depending on which
767 way the frame grows. We include the extra space if and only if it
768 is above this slot. */
769 #ifdef FRAME_GROWS_DOWNWARD
770 p->size = frame_offset_old - frame_offset;
775 /* Now define the fields used by combine_temp_slots. */
776 #ifdef FRAME_GROWS_DOWNWARD
777 p->base_offset = frame_offset;
778 p->full_size = frame_offset_old - frame_offset;
780 p->base_offset = frame_offset_old;
781 p->full_size = frame_offset - frame_offset_old;
784 p->next = temp_slots;
790 p->rtl_expr = seq_rtl_expr;
795 p->level = target_temp_slot_level;
800 p->level = var_temp_slot_level;
805 p->level = temp_slot_level;
810 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
811 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
812 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list);
814 /* If we know the alias set for the memory that will be used, use
815 it. If there's no TYPE, then we don't know anything about the
816 alias set for the memory. */
817 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
818 set_mem_align (slot, align);
820 /* If a type is specified, set the relevant flags. */
823 RTX_UNCHANGING_P (slot) = (lang_hooks.honor_readonly
824 && TYPE_READONLY (type));
825 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
826 MEM_SET_IN_STRUCT_P (slot, AGGREGATE_TYPE_P (type));
832 /* Allocate a temporary stack slot and record it for possible later
833 reuse. First three arguments are same as in preceding function. */
836 assign_stack_temp (mode, size, keep)
837 enum machine_mode mode;
841 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
844 /* Assign a temporary.
845 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
846 and so that should be used in error messages. In either case, we
847 allocate of the given type.
848 KEEP is as for assign_stack_temp.
849 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
850 it is 0 if a register is OK.
851 DONT_PROMOTE is 1 if we should not promote values in register
855 assign_temp (type_or_decl, keep, memory_required, dont_promote)
859 int dont_promote ATTRIBUTE_UNUSED;
862 enum machine_mode mode;
863 #ifndef PROMOTE_FOR_CALL_ONLY
867 if (DECL_P (type_or_decl))
868 decl = type_or_decl, type = TREE_TYPE (decl);
870 decl = NULL, type = type_or_decl;
872 mode = TYPE_MODE (type);
873 #ifndef PROMOTE_FOR_CALL_ONLY
874 unsignedp = TREE_UNSIGNED (type);
877 if (mode == BLKmode || memory_required)
879 HOST_WIDE_INT size = int_size_in_bytes (type);
882 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
883 problems with allocating the stack space. */
887 /* Unfortunately, we don't yet know how to allocate variable-sized
888 temporaries. However, sometimes we have a fixed upper limit on
889 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
890 instead. This is the case for Chill variable-sized strings. */
891 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
892 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
893 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
894 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
896 /* The size of the temporary may be too large to fit into an integer. */
897 /* ??? Not sure this should happen except for user silliness, so limit
898 this to things that aren't compiler-generated temporaries. The
899 rest of the time we'll abort in assign_stack_temp_for_type. */
900 if (decl && size == -1
901 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
903 error_with_decl (decl, "size of variable `%s' is too large");
907 tmp = assign_stack_temp_for_type (mode, size, keep, type);
911 #ifndef PROMOTE_FOR_CALL_ONLY
913 mode = promote_mode (type, mode, &unsignedp, 0);
916 return gen_reg_rtx (mode);
919 /* Combine temporary stack slots which are adjacent on the stack.
921 This allows for better use of already allocated stack space. This is only
922 done for BLKmode slots because we can be sure that we won't have alignment
923 problems in this case. */
926 combine_temp_slots ()
928 struct temp_slot *p, *q;
929 struct temp_slot *prev_p, *prev_q;
932 /* We can't combine slots, because the information about which slot
933 is in which alias set will be lost. */
934 if (flag_strict_aliasing)
937 /* If there are a lot of temp slots, don't do anything unless
938 high levels of optimization. */
939 if (! flag_expensive_optimizations)
940 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
941 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
944 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
948 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
949 for (q = p->next, prev_q = p; q; q = prev_q->next)
952 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
954 if (p->base_offset + p->full_size == q->base_offset)
956 /* Q comes after P; combine Q into P. */
958 p->full_size += q->full_size;
961 else if (q->base_offset + q->full_size == p->base_offset)
963 /* P comes after Q; combine P into Q. */
965 q->full_size += p->full_size;
970 /* Either delete Q or advance past it. */
972 prev_q->next = q->next;
976 /* Either delete P or advance past it. */
980 prev_p->next = p->next;
982 temp_slots = p->next;
989 /* Find the temp slot corresponding to the object at address X. */
991 static struct temp_slot *
992 find_temp_slot_from_address (x)
998 for (p = temp_slots; p; p = p->next)
1003 else if (XEXP (p->slot, 0) == x
1005 || (GET_CODE (x) == PLUS
1006 && XEXP (x, 0) == virtual_stack_vars_rtx
1007 && GET_CODE (XEXP (x, 1)) == CONST_INT
1008 && INTVAL (XEXP (x, 1)) >= p->base_offset
1009 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
1012 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
1013 for (next = p->address; next; next = XEXP (next, 1))
1014 if (XEXP (next, 0) == x)
1018 /* If we have a sum involving a register, see if it points to a temp
1020 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == REG
1021 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
1023 else if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == REG
1024 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
1030 /* Indicate that NEW is an alternate way of referring to the temp slot
1031 that previously was known by OLD. */
1034 update_temp_slot_address (old, new)
1037 struct temp_slot *p;
1039 if (rtx_equal_p (old, new))
1042 p = find_temp_slot_from_address (old);
1044 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
1045 is a register, see if one operand of the PLUS is a temporary
1046 location. If so, NEW points into it. Otherwise, if both OLD and
1047 NEW are a PLUS and if there is a register in common between them.
1048 If so, try a recursive call on those values. */
1051 if (GET_CODE (old) != PLUS)
1054 if (GET_CODE (new) == REG)
1056 update_temp_slot_address (XEXP (old, 0), new);
1057 update_temp_slot_address (XEXP (old, 1), new);
1060 else if (GET_CODE (new) != PLUS)
1063 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
1064 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
1065 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
1066 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
1067 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
1068 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
1069 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
1070 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
1075 /* Otherwise add an alias for the temp's address. */
1076 else if (p->address == 0)
1080 if (GET_CODE (p->address) != EXPR_LIST)
1081 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1083 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1087 /* If X could be a reference to a temporary slot, mark the fact that its
1088 address was taken. */
1091 mark_temp_addr_taken (x)
1094 struct temp_slot *p;
1099 /* If X is not in memory or is at a constant address, it cannot be in
1100 a temporary slot. */
1101 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1104 p = find_temp_slot_from_address (XEXP (x, 0));
1109 /* If X could be a reference to a temporary slot, mark that slot as
1110 belonging to the to one level higher than the current level. If X
1111 matched one of our slots, just mark that one. Otherwise, we can't
1112 easily predict which it is, so upgrade all of them. Kept slots
1113 need not be touched.
1115 This is called when an ({...}) construct occurs and a statement
1116 returns a value in memory. */
1119 preserve_temp_slots (x)
1122 struct temp_slot *p = 0;
1124 /* If there is no result, we still might have some objects whose address
1125 were taken, so we need to make sure they stay around. */
1128 for (p = temp_slots; p; p = p->next)
1129 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1135 /* If X is a register that is being used as a pointer, see if we have
1136 a temporary slot we know it points to. To be consistent with
1137 the code below, we really should preserve all non-kept slots
1138 if we can't find a match, but that seems to be much too costly. */
1139 if (GET_CODE (x) == REG && REG_POINTER (x))
1140 p = find_temp_slot_from_address (x);
1142 /* If X is not in memory or is at a constant address, it cannot be in
1143 a temporary slot, but it can contain something whose address was
1145 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1147 for (p = temp_slots; p; p = p->next)
1148 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1154 /* First see if we can find a match. */
1156 p = find_temp_slot_from_address (XEXP (x, 0));
1160 /* Move everything at our level whose address was taken to our new
1161 level in case we used its address. */
1162 struct temp_slot *q;
1164 if (p->level == temp_slot_level)
1166 for (q = temp_slots; q; q = q->next)
1167 if (q != p && q->addr_taken && q->level == p->level)
1176 /* Otherwise, preserve all non-kept slots at this level. */
1177 for (p = temp_slots; p; p = p->next)
1178 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1182 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1183 with that RTL_EXPR, promote it into a temporary slot at the present
1184 level so it will not be freed when we free slots made in the
1188 preserve_rtl_expr_result (x)
1191 struct temp_slot *p;
1193 /* If X is not in memory or is at a constant address, it cannot be in
1194 a temporary slot. */
1195 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1198 /* If we can find a match, move it to our level unless it is already at
1200 p = find_temp_slot_from_address (XEXP (x, 0));
1203 p->level = MIN (p->level, temp_slot_level);
1210 /* Free all temporaries used so far. This is normally called at the end
1211 of generating code for a statement. Don't free any temporaries
1212 currently in use for an RTL_EXPR that hasn't yet been emitted.
1213 We could eventually do better than this since it can be reused while
1214 generating the same RTL_EXPR, but this is complex and probably not
1220 struct temp_slot *p;
1222 for (p = temp_slots; p; p = p->next)
1223 if (p->in_use && p->level == temp_slot_level && ! p->keep
1224 && p->rtl_expr == 0)
1227 combine_temp_slots ();
1230 /* Free all temporary slots used in T, an RTL_EXPR node. */
1233 free_temps_for_rtl_expr (t)
1236 struct temp_slot *p;
1238 for (p = temp_slots; p; p = p->next)
1239 if (p->rtl_expr == t)
1241 /* If this slot is below the current TEMP_SLOT_LEVEL, then it
1242 needs to be preserved. This can happen if a temporary in
1243 the RTL_EXPR was addressed; preserve_temp_slots will move
1244 the temporary into a higher level. */
1245 if (temp_slot_level <= p->level)
1248 p->rtl_expr = NULL_TREE;
1251 combine_temp_slots ();
1254 /* Mark all temporaries ever allocated in this function as not suitable
1255 for reuse until the current level is exited. */
1258 mark_all_temps_used ()
1260 struct temp_slot *p;
1262 for (p = temp_slots; p; p = p->next)
1264 p->in_use = p->keep = 1;
1265 p->level = MIN (p->level, temp_slot_level);
1269 /* Push deeper into the nesting level for stack temporaries. */
1277 /* Pop a temporary nesting level. All slots in use in the current level
1283 struct temp_slot *p;
1285 for (p = temp_slots; p; p = p->next)
1286 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1289 combine_temp_slots ();
1294 /* Initialize temporary slots. */
1299 /* We have not allocated any temporaries yet. */
1301 temp_slot_level = 0;
1302 var_temp_slot_level = 0;
1303 target_temp_slot_level = 0;
1306 /* Retroactively move an auto variable from a register to a stack slot.
1307 This is done when an address-reference to the variable is seen. */
1310 put_var_into_stack (decl)
1314 enum machine_mode promoted_mode, decl_mode;
1315 struct function *function = 0;
1317 int can_use_addressof;
1318 int volatilep = TREE_CODE (decl) != SAVE_EXPR && TREE_THIS_VOLATILE (decl);
1319 int usedp = (TREE_USED (decl)
1320 || (TREE_CODE (decl) != SAVE_EXPR && DECL_INITIAL (decl) != 0));
1322 context = decl_function_context (decl);
1324 /* Get the current rtl used for this object and its original mode. */
1325 reg = (TREE_CODE (decl) == SAVE_EXPR
1326 ? SAVE_EXPR_RTL (decl)
1327 : DECL_RTL_IF_SET (decl));
1329 /* No need to do anything if decl has no rtx yet
1330 since in that case caller is setting TREE_ADDRESSABLE
1331 and a stack slot will be assigned when the rtl is made. */
1335 /* Get the declared mode for this object. */
1336 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1337 : DECL_MODE (decl));
1338 /* Get the mode it's actually stored in. */
1339 promoted_mode = GET_MODE (reg);
1341 /* If this variable comes from an outer function, find that
1342 function's saved context. Don't use find_function_data here,
1343 because it might not be in any active function.
1344 FIXME: Is that really supposed to happen?
1345 It does in ObjC at least. */
1346 if (context != current_function_decl && context != inline_function_decl)
1347 for (function = outer_function_chain; function; function = function->outer)
1348 if (function->decl == context)
1351 /* If this is a variable-size object with a pseudo to address it,
1352 put that pseudo into the stack, if the var is nonlocal. */
1353 if (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl)
1354 && GET_CODE (reg) == MEM
1355 && GET_CODE (XEXP (reg, 0)) == REG
1356 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1358 reg = XEXP (reg, 0);
1359 decl_mode = promoted_mode = GET_MODE (reg);
1365 /* FIXME make it work for promoted modes too */
1366 && decl_mode == promoted_mode
1367 #ifdef NON_SAVING_SETJMP
1368 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1372 /* If we can't use ADDRESSOF, make sure we see through one we already
1374 if (! can_use_addressof && GET_CODE (reg) == MEM
1375 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1376 reg = XEXP (XEXP (reg, 0), 0);
1378 /* Now we should have a value that resides in one or more pseudo regs. */
1380 if (GET_CODE (reg) == REG)
1382 /* If this variable lives in the current function and we don't need
1383 to put things in the stack for the sake of setjmp, try to keep it
1384 in a register until we know we actually need the address. */
1385 if (can_use_addressof)
1386 gen_mem_addressof (reg, decl);
1388 put_reg_into_stack (function, reg, TREE_TYPE (decl), promoted_mode,
1389 decl_mode, volatilep, 0, usedp, 0);
1391 else if (GET_CODE (reg) == CONCAT)
1393 /* A CONCAT contains two pseudos; put them both in the stack.
1394 We do it so they end up consecutive.
1395 We fixup references to the parts only after we fixup references
1396 to the whole CONCAT, lest we do double fixups for the latter
1398 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1399 tree part_type = (*lang_hooks.types.type_for_mode) (part_mode, 0);
1400 rtx lopart = XEXP (reg, 0);
1401 rtx hipart = XEXP (reg, 1);
1402 #ifdef FRAME_GROWS_DOWNWARD
1403 /* Since part 0 should have a lower address, do it second. */
1404 put_reg_into_stack (function, hipart, part_type, part_mode,
1405 part_mode, volatilep, 0, 0, 0);
1406 put_reg_into_stack (function, lopart, part_type, part_mode,
1407 part_mode, volatilep, 0, 0, 0);
1409 put_reg_into_stack (function, lopart, part_type, part_mode,
1410 part_mode, volatilep, 0, 0, 0);
1411 put_reg_into_stack (function, hipart, part_type, part_mode,
1412 part_mode, volatilep, 0, 0, 0);
1415 /* Change the CONCAT into a combined MEM for both parts. */
1416 PUT_CODE (reg, MEM);
1417 MEM_ATTRS (reg) = 0;
1419 /* set_mem_attributes uses DECL_RTL to avoid re-generating of
1420 already computed alias sets. Here we want to re-generate. */
1422 SET_DECL_RTL (decl, NULL);
1423 set_mem_attributes (reg, decl, 1);
1425 SET_DECL_RTL (decl, reg);
1427 /* The two parts are in memory order already.
1428 Use the lower parts address as ours. */
1429 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1430 /* Prevent sharing of rtl that might lose. */
1431 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1432 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1435 schedule_fixup_var_refs (function, reg, TREE_TYPE (decl),
1437 schedule_fixup_var_refs (function, lopart, part_type, part_mode, 0);
1438 schedule_fixup_var_refs (function, hipart, part_type, part_mode, 0);
1445 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1446 into the stack frame of FUNCTION (0 means the current function).
1447 DECL_MODE is the machine mode of the user-level data type.
1448 PROMOTED_MODE is the machine mode of the register.
1449 VOLATILE_P is nonzero if this is for a "volatile" decl.
1450 USED_P is nonzero if this reg might have already been used in an insn. */
1453 put_reg_into_stack (function, reg, type, promoted_mode, decl_mode, volatile_p,
1454 original_regno, used_p, ht)
1455 struct function *function;
1458 enum machine_mode promoted_mode, decl_mode;
1460 unsigned int original_regno;
1464 struct function *func = function ? function : cfun;
1466 unsigned int regno = original_regno;
1469 regno = REGNO (reg);
1471 if (regno < func->x_max_parm_reg)
1472 new = func->x_parm_reg_stack_loc[regno];
1475 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode), 0, func);
1477 PUT_CODE (reg, MEM);
1478 PUT_MODE (reg, decl_mode);
1479 XEXP (reg, 0) = XEXP (new, 0);
1480 MEM_ATTRS (reg) = 0;
1481 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1482 MEM_VOLATILE_P (reg) = volatile_p;
1484 /* If this is a memory ref that contains aggregate components,
1485 mark it as such for cse and loop optimize. If we are reusing a
1486 previously generated stack slot, then we need to copy the bit in
1487 case it was set for other reasons. For instance, it is set for
1488 __builtin_va_alist. */
1491 MEM_SET_IN_STRUCT_P (reg,
1492 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1493 set_mem_alias_set (reg, get_alias_set (type));
1497 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht);
1500 /* Make sure that all refs to the variable, previously made
1501 when it was a register, are fixed up to be valid again.
1502 See function above for meaning of arguments. */
1505 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht)
1506 struct function *function;
1509 enum machine_mode promoted_mode;
1512 int unsigned_p = type ? TREE_UNSIGNED (type) : 0;
1516 struct var_refs_queue *temp;
1519 = (struct var_refs_queue *) ggc_alloc (sizeof (struct var_refs_queue));
1520 temp->modified = reg;
1521 temp->promoted_mode = promoted_mode;
1522 temp->unsignedp = unsigned_p;
1523 temp->next = function->fixup_var_refs_queue;
1524 function->fixup_var_refs_queue = temp;
1527 /* Variable is local; fix it up now. */
1528 fixup_var_refs (reg, promoted_mode, unsigned_p, reg, ht);
1532 fixup_var_refs (var, promoted_mode, unsignedp, may_share, ht)
1534 enum machine_mode promoted_mode;
1540 rtx first_insn = get_insns ();
1541 struct sequence_stack *stack = seq_stack;
1542 tree rtl_exps = rtl_expr_chain;
1544 /* If there's a hash table, it must record all uses of VAR. */
1549 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp,
1554 fixup_var_refs_insns (first_insn, var, promoted_mode, unsignedp,
1555 stack == 0, may_share);
1557 /* Scan all pending sequences too. */
1558 for (; stack; stack = stack->next)
1560 push_to_full_sequence (stack->first, stack->last);
1561 fixup_var_refs_insns (stack->first, var, promoted_mode, unsignedp,
1562 stack->next != 0, may_share);
1563 /* Update remembered end of sequence
1564 in case we added an insn at the end. */
1565 stack->last = get_last_insn ();
1569 /* Scan all waiting RTL_EXPRs too. */
1570 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1572 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1573 if (seq != const0_rtx && seq != 0)
1575 push_to_sequence (seq);
1576 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1583 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1584 some part of an insn. Return a struct fixup_replacement whose OLD
1585 value is equal to X. Allocate a new structure if no such entry exists. */
1587 static struct fixup_replacement *
1588 find_fixup_replacement (replacements, x)
1589 struct fixup_replacement **replacements;
1592 struct fixup_replacement *p;
1594 /* See if we have already replaced this. */
1595 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1600 p = (struct fixup_replacement *) xmalloc (sizeof (struct fixup_replacement));
1603 p->next = *replacements;
1610 /* Scan the insn-chain starting with INSN for refs to VAR and fix them
1611 up. TOPLEVEL is nonzero if this chain is the main chain of insns
1612 for the current function. MAY_SHARE is either a MEM that is not
1613 to be unshared or a list of them. */
1616 fixup_var_refs_insns (insn, var, promoted_mode, unsignedp, toplevel, may_share)
1619 enum machine_mode promoted_mode;
1626 /* fixup_var_refs_insn might modify insn, so save its next
1628 rtx next = NEXT_INSN (insn);
1630 /* CALL_PLACEHOLDERs are special; we have to switch into each of
1631 the three sequences they (potentially) contain, and process
1632 them recursively. The CALL_INSN itself is not interesting. */
1634 if (GET_CODE (insn) == CALL_INSN
1635 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
1639 /* Look at the Normal call, sibling call and tail recursion
1640 sequences attached to the CALL_PLACEHOLDER. */
1641 for (i = 0; i < 3; i++)
1643 rtx seq = XEXP (PATTERN (insn), i);
1646 push_to_sequence (seq);
1647 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1649 XEXP (PATTERN (insn), i) = get_insns ();
1655 else if (INSN_P (insn))
1656 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel,
1663 /* Look up the insns which reference VAR in HT and fix them up. Other
1664 arguments are the same as fixup_var_refs_insns.
1666 N.B. No need for special processing of CALL_PLACEHOLDERs here,
1667 because the hash table will point straight to the interesting insn
1668 (inside the CALL_PLACEHOLDER). */
1671 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp, may_share)
1674 enum machine_mode promoted_mode;
1678 struct insns_for_mem_entry tmp;
1679 struct insns_for_mem_entry *ime;
1683 ime = (struct insns_for_mem_entry *) htab_find (ht, &tmp);
1684 for (insn_list = ime->insns; insn_list != 0; insn_list = XEXP (insn_list, 1))
1685 if (INSN_P (XEXP (insn_list, 0)))
1686 fixup_var_refs_insn (XEXP (insn_list, 0), var, promoted_mode,
1687 unsignedp, 1, may_share);
1691 /* Per-insn processing by fixup_var_refs_insns(_with_hash). INSN is
1692 the insn under examination, VAR is the variable to fix up
1693 references to, PROMOTED_MODE and UNSIGNEDP describe VAR, and
1694 TOPLEVEL is nonzero if this is the main insn chain for this
1698 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel, no_share)
1701 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,
1734 /* The insn to load VAR from a home in the arglist
1735 is now a no-op. When we see it, just delete it.
1736 Similarly if this is storing VAR from a register from which
1737 it was loaded in the previous insn. This will occur
1738 when an ADDRESSOF was made for an arglist slot. */
1740 && (set = single_set (insn)) != 0
1741 && SET_DEST (set) == var
1742 /* If this represents the result of an insn group,
1743 don't delete the insn. */
1744 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1745 && (rtx_equal_p (SET_SRC (set), var)
1746 || (GET_CODE (SET_SRC (set)) == REG
1747 && (prev = prev_nonnote_insn (insn)) != 0
1748 && (prev_set = single_set (prev)) != 0
1749 && SET_DEST (prev_set) == SET_SRC (set)
1750 && rtx_equal_p (SET_SRC (prev_set), var))))
1756 struct fixup_replacement *replacements = 0;
1757 rtx next_insn = NEXT_INSN (insn);
1759 if (SMALL_REGISTER_CLASSES)
1761 /* If the insn that copies the results of a CALL_INSN
1762 into a pseudo now references VAR, we have to use an
1763 intermediate pseudo since we want the life of the
1764 return value register to be only a single insn.
1766 If we don't use an intermediate pseudo, such things as
1767 address computations to make the address of VAR valid
1768 if it is not can be placed between the CALL_INSN and INSN.
1770 To make sure this doesn't happen, we record the destination
1771 of the CALL_INSN and see if the next insn uses both that
1774 if (call_dest != 0 && GET_CODE (insn) == INSN
1775 && reg_mentioned_p (var, PATTERN (insn))
1776 && reg_mentioned_p (call_dest, PATTERN (insn)))
1778 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1780 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1782 PATTERN (insn) = replace_rtx (PATTERN (insn),
1786 if (GET_CODE (insn) == CALL_INSN
1787 && GET_CODE (PATTERN (insn)) == SET)
1788 call_dest = SET_DEST (PATTERN (insn));
1789 else if (GET_CODE (insn) == CALL_INSN
1790 && GET_CODE (PATTERN (insn)) == PARALLEL
1791 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1792 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1797 /* See if we have to do anything to INSN now that VAR is in
1798 memory. If it needs to be loaded into a pseudo, use a single
1799 pseudo for the entire insn in case there is a MATCH_DUP
1800 between two operands. We pass a pointer to the head of
1801 a list of struct fixup_replacements. If fixup_var_refs_1
1802 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1803 it will record them in this list.
1805 If it allocated a pseudo for any replacement, we copy into
1808 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1809 &replacements, no_share);
1811 /* If this is last_parm_insn, and any instructions were output
1812 after it to fix it up, then we must set last_parm_insn to
1813 the last such instruction emitted. */
1814 if (insn == last_parm_insn)
1815 last_parm_insn = PREV_INSN (next_insn);
1817 while (replacements)
1819 struct fixup_replacement *next;
1821 if (GET_CODE (replacements->new) == REG)
1826 /* OLD might be a (subreg (mem)). */
1827 if (GET_CODE (replacements->old) == SUBREG)
1829 = fixup_memory_subreg (replacements->old, insn,
1833 = fixup_stack_1 (replacements->old, insn);
1835 insert_before = insn;
1837 /* If we are changing the mode, do a conversion.
1838 This might be wasteful, but combine.c will
1839 eliminate much of the waste. */
1841 if (GET_MODE (replacements->new)
1842 != GET_MODE (replacements->old))
1845 convert_move (replacements->new,
1846 replacements->old, unsignedp);
1851 seq = gen_move_insn (replacements->new,
1854 emit_insn_before (seq, insert_before);
1857 next = replacements->next;
1858 free (replacements);
1859 replacements = next;
1863 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1864 But don't touch other insns referred to by reg-notes;
1865 we will get them elsewhere. */
1868 if (GET_CODE (note) != INSN_LIST)
1870 = walk_fixup_memory_subreg (XEXP (note, 0), insn,
1872 note = XEXP (note, 1);
1876 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1877 See if the rtx expression at *LOC in INSN needs to be changed.
1879 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1880 contain a list of original rtx's and replacements. If we find that we need
1881 to modify this insn by replacing a memory reference with a pseudo or by
1882 making a new MEM to implement a SUBREG, we consult that list to see if
1883 we have already chosen a replacement. If none has already been allocated,
1884 we allocate it and update the list. fixup_var_refs_insn will copy VAR
1885 or the SUBREG, as appropriate, to the pseudo. */
1888 fixup_var_refs_1 (var, promoted_mode, loc, insn, replacements, no_share)
1890 enum machine_mode promoted_mode;
1893 struct fixup_replacement **replacements;
1898 RTX_CODE code = GET_CODE (x);
1901 struct fixup_replacement *replacement;
1906 if (XEXP (x, 0) == var)
1908 /* Prevent sharing of rtl that might lose. */
1909 rtx sub = copy_rtx (XEXP (var, 0));
1911 if (! validate_change (insn, loc, sub, 0))
1913 rtx y = gen_reg_rtx (GET_MODE (sub));
1916 /* We should be able to replace with a register or all is lost.
1917 Note that we can't use validate_change to verify this, since
1918 we're not caring for replacing all dups simultaneously. */
1919 if (! validate_replace_rtx (*loc, y, insn))
1922 /* Careful! First try to recognize a direct move of the
1923 value, mimicking how things are done in gen_reload wrt
1924 PLUS. Consider what happens when insn is a conditional
1925 move instruction and addsi3 clobbers flags. */
1928 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1932 if (recog_memoized (new_insn) < 0)
1934 /* That failed. Fall back on force_operand and hope. */
1937 sub = force_operand (sub, y);
1939 emit_insn (gen_move_insn (y, sub));
1945 /* Don't separate setter from user. */
1946 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1947 insn = PREV_INSN (insn);
1950 emit_insn_before (seq, insn);
1958 /* If we already have a replacement, use it. Otherwise,
1959 try to fix up this address in case it is invalid. */
1961 replacement = find_fixup_replacement (replacements, var);
1962 if (replacement->new)
1964 *loc = replacement->new;
1968 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1970 /* Unless we are forcing memory to register or we changed the mode,
1971 we can leave things the way they are if the insn is valid. */
1973 INSN_CODE (insn) = -1;
1974 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1975 && recog_memoized (insn) >= 0)
1978 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1982 /* If X contains VAR, we need to unshare it here so that we update
1983 each occurrence separately. But all identical MEMs in one insn
1984 must be replaced with the same rtx because of the possibility of
1987 if (reg_mentioned_p (var, x))
1989 replacement = find_fixup_replacement (replacements, x);
1990 if (replacement->new == 0)
1991 replacement->new = copy_most_rtx (x, no_share);
1993 *loc = x = replacement->new;
1994 code = GET_CODE (x);
2011 /* Note that in some cases those types of expressions are altered
2012 by optimize_bit_field, and do not survive to get here. */
2013 if (XEXP (x, 0) == var
2014 || (GET_CODE (XEXP (x, 0)) == SUBREG
2015 && SUBREG_REG (XEXP (x, 0)) == var))
2017 /* Get TEM as a valid MEM in the mode presently in the insn.
2019 We don't worry about the possibility of MATCH_DUP here; it
2020 is highly unlikely and would be tricky to handle. */
2023 if (GET_CODE (tem) == SUBREG)
2025 if (GET_MODE_BITSIZE (GET_MODE (tem))
2026 > GET_MODE_BITSIZE (GET_MODE (var)))
2028 replacement = find_fixup_replacement (replacements, var);
2029 if (replacement->new == 0)
2030 replacement->new = gen_reg_rtx (GET_MODE (var));
2031 SUBREG_REG (tem) = replacement->new;
2033 /* The following code works only if we have a MEM, so we
2034 need to handle the subreg here. We directly substitute
2035 it assuming that a subreg must be OK here. We already
2036 scheduled a replacement to copy the mem into the
2042 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
2045 tem = fixup_stack_1 (tem, insn);
2047 /* Unless we want to load from memory, get TEM into the proper mode
2048 for an extract from memory. This can only be done if the
2049 extract is at a constant position and length. */
2051 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
2052 && GET_CODE (XEXP (x, 2)) == CONST_INT
2053 && ! mode_dependent_address_p (XEXP (tem, 0))
2054 && ! MEM_VOLATILE_P (tem))
2056 enum machine_mode wanted_mode = VOIDmode;
2057 enum machine_mode is_mode = GET_MODE (tem);
2058 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
2060 if (GET_CODE (x) == ZERO_EXTRACT)
2062 enum machine_mode new_mode
2063 = mode_for_extraction (EP_extzv, 1);
2064 if (new_mode != MAX_MACHINE_MODE)
2065 wanted_mode = new_mode;
2067 else if (GET_CODE (x) == SIGN_EXTRACT)
2069 enum machine_mode new_mode
2070 = mode_for_extraction (EP_extv, 1);
2071 if (new_mode != MAX_MACHINE_MODE)
2072 wanted_mode = new_mode;
2075 /* If we have a narrower mode, we can do something. */
2076 if (wanted_mode != VOIDmode
2077 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2079 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2080 rtx old_pos = XEXP (x, 2);
2083 /* If the bytes and bits are counted differently, we
2084 must adjust the offset. */
2085 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2086 offset = (GET_MODE_SIZE (is_mode)
2087 - GET_MODE_SIZE (wanted_mode) - offset);
2089 pos %= GET_MODE_BITSIZE (wanted_mode);
2091 newmem = adjust_address_nv (tem, wanted_mode, offset);
2093 /* Make the change and see if the insn remains valid. */
2094 INSN_CODE (insn) = -1;
2095 XEXP (x, 0) = newmem;
2096 XEXP (x, 2) = GEN_INT (pos);
2098 if (recog_memoized (insn) >= 0)
2101 /* Otherwise, restore old position. XEXP (x, 0) will be
2103 XEXP (x, 2) = old_pos;
2107 /* If we get here, the bitfield extract insn can't accept a memory
2108 reference. Copy the input into a register. */
2110 tem1 = gen_reg_rtx (GET_MODE (tem));
2111 emit_insn_before (gen_move_insn (tem1, tem), insn);
2118 if (SUBREG_REG (x) == var)
2120 /* If this is a special SUBREG made because VAR was promoted
2121 from a wider mode, replace it with VAR and call ourself
2122 recursively, this time saying that the object previously
2123 had its current mode (by virtue of the SUBREG). */
2125 if (SUBREG_PROMOTED_VAR_P (x))
2128 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements,
2133 /* If this SUBREG makes VAR wider, it has become a paradoxical
2134 SUBREG with VAR in memory, but these aren't allowed at this
2135 stage of the compilation. So load VAR into a pseudo and take
2136 a SUBREG of that pseudo. */
2137 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2139 replacement = find_fixup_replacement (replacements, var);
2140 if (replacement->new == 0)
2141 replacement->new = gen_reg_rtx (promoted_mode);
2142 SUBREG_REG (x) = replacement->new;
2146 /* See if we have already found a replacement for this SUBREG.
2147 If so, use it. Otherwise, make a MEM and see if the insn
2148 is recognized. If not, or if we should force MEM into a register,
2149 make a pseudo for this SUBREG. */
2150 replacement = find_fixup_replacement (replacements, x);
2151 if (replacement->new)
2153 *loc = replacement->new;
2157 replacement->new = *loc = fixup_memory_subreg (x, insn,
2160 INSN_CODE (insn) = -1;
2161 if (! flag_force_mem && recog_memoized (insn) >= 0)
2164 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2170 /* First do special simplification of bit-field references. */
2171 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2172 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2173 optimize_bit_field (x, insn, 0);
2174 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2175 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2176 optimize_bit_field (x, insn, 0);
2178 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2179 into a register and then store it back out. */
2180 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2181 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2182 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2183 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2184 > GET_MODE_SIZE (GET_MODE (var))))
2186 replacement = find_fixup_replacement (replacements, var);
2187 if (replacement->new == 0)
2188 replacement->new = gen_reg_rtx (GET_MODE (var));
2190 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2191 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2194 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2195 insn into a pseudo and store the low part of the pseudo into VAR. */
2196 if (GET_CODE (SET_DEST (x)) == SUBREG
2197 && SUBREG_REG (SET_DEST (x)) == var
2198 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2199 > GET_MODE_SIZE (GET_MODE (var))))
2201 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2202 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2209 rtx dest = SET_DEST (x);
2210 rtx src = SET_SRC (x);
2211 rtx outerdest = dest;
2213 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2214 || GET_CODE (dest) == SIGN_EXTRACT
2215 || GET_CODE (dest) == ZERO_EXTRACT)
2216 dest = XEXP (dest, 0);
2218 if (GET_CODE (src) == SUBREG)
2219 src = SUBREG_REG (src);
2221 /* If VAR does not appear at the top level of the SET
2222 just scan the lower levels of the tree. */
2224 if (src != var && dest != var)
2227 /* We will need to rerecognize this insn. */
2228 INSN_CODE (insn) = -1;
2230 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var
2231 && mode_for_extraction (EP_insv, -1) != MAX_MACHINE_MODE)
2233 /* Since this case will return, ensure we fixup all the
2235 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2236 insn, replacements, no_share);
2237 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2238 insn, replacements, no_share);
2239 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2240 insn, replacements, no_share);
2242 tem = XEXP (outerdest, 0);
2244 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2245 that may appear inside a ZERO_EXTRACT.
2246 This was legitimate when the MEM was a REG. */
2247 if (GET_CODE (tem) == SUBREG
2248 && SUBREG_REG (tem) == var)
2249 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
2251 tem = fixup_stack_1 (tem, insn);
2253 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2254 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2255 && ! mode_dependent_address_p (XEXP (tem, 0))
2256 && ! MEM_VOLATILE_P (tem))
2258 enum machine_mode wanted_mode;
2259 enum machine_mode is_mode = GET_MODE (tem);
2260 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2262 wanted_mode = mode_for_extraction (EP_insv, 0);
2264 /* If we have a narrower mode, we can do something. */
2265 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2267 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2268 rtx old_pos = XEXP (outerdest, 2);
2271 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2272 offset = (GET_MODE_SIZE (is_mode)
2273 - GET_MODE_SIZE (wanted_mode) - offset);
2275 pos %= GET_MODE_BITSIZE (wanted_mode);
2277 newmem = adjust_address_nv (tem, wanted_mode, offset);
2279 /* Make the change and see if the insn remains valid. */
2280 INSN_CODE (insn) = -1;
2281 XEXP (outerdest, 0) = newmem;
2282 XEXP (outerdest, 2) = GEN_INT (pos);
2284 if (recog_memoized (insn) >= 0)
2287 /* Otherwise, restore old position. XEXP (x, 0) will be
2289 XEXP (outerdest, 2) = old_pos;
2293 /* If we get here, the bit-field store doesn't allow memory
2294 or isn't located at a constant position. Load the value into
2295 a register, do the store, and put it back into memory. */
2297 tem1 = gen_reg_rtx (GET_MODE (tem));
2298 emit_insn_before (gen_move_insn (tem1, tem), insn);
2299 emit_insn_after (gen_move_insn (tem, tem1), insn);
2300 XEXP (outerdest, 0) = tem1;
2304 /* STRICT_LOW_PART is a no-op on memory references
2305 and it can cause combinations to be unrecognizable,
2308 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2309 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2311 /* A valid insn to copy VAR into or out of a register
2312 must be left alone, to avoid an infinite loop here.
2313 If the reference to VAR is by a subreg, fix that up,
2314 since SUBREG is not valid for a memref.
2315 Also fix up the address of the stack slot.
2317 Note that we must not try to recognize the insn until
2318 after we know that we have valid addresses and no
2319 (subreg (mem ...) ...) constructs, since these interfere
2320 with determining the validity of the insn. */
2322 if ((SET_SRC (x) == var
2323 || (GET_CODE (SET_SRC (x)) == SUBREG
2324 && SUBREG_REG (SET_SRC (x)) == var))
2325 && (GET_CODE (SET_DEST (x)) == REG
2326 || (GET_CODE (SET_DEST (x)) == SUBREG
2327 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2328 && GET_MODE (var) == promoted_mode
2329 && x == single_set (insn))
2333 if (GET_CODE (SET_SRC (x)) == SUBREG
2334 && (GET_MODE_SIZE (GET_MODE (SET_SRC (x)))
2335 > GET_MODE_SIZE (GET_MODE (var))))
2337 /* This (subreg VAR) is now a paradoxical subreg. We need
2338 to replace VAR instead of the subreg. */
2339 replacement = find_fixup_replacement (replacements, var);
2340 if (replacement->new == NULL_RTX)
2341 replacement->new = gen_reg_rtx (GET_MODE (var));
2342 SUBREG_REG (SET_SRC (x)) = replacement->new;
2346 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2347 if (replacement->new)
2348 SET_SRC (x) = replacement->new;
2349 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2350 SET_SRC (x) = replacement->new
2351 = fixup_memory_subreg (SET_SRC (x), insn, promoted_mode,
2354 SET_SRC (x) = replacement->new
2355 = fixup_stack_1 (SET_SRC (x), insn);
2358 if (recog_memoized (insn) >= 0)
2361 /* INSN is not valid, but we know that we want to
2362 copy SET_SRC (x) to SET_DEST (x) in some way. So
2363 we generate the move and see whether it requires more
2364 than one insn. If it does, we emit those insns and
2365 delete INSN. Otherwise, we can just replace the pattern
2366 of INSN; we have already verified above that INSN has
2367 no other function that to do X. */
2369 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2370 if (NEXT_INSN (pat) != NULL_RTX)
2372 last = emit_insn_before (pat, insn);
2374 /* INSN might have REG_RETVAL or other important notes, so
2375 we need to store the pattern of the last insn in the
2376 sequence into INSN similarly to the normal case. LAST
2377 should not have REG_NOTES, but we allow them if INSN has
2379 if (REG_NOTES (last) && REG_NOTES (insn))
2381 if (REG_NOTES (last))
2382 REG_NOTES (insn) = REG_NOTES (last);
2383 PATTERN (insn) = PATTERN (last);
2388 PATTERN (insn) = PATTERN (pat);
2393 if ((SET_DEST (x) == var
2394 || (GET_CODE (SET_DEST (x)) == SUBREG
2395 && SUBREG_REG (SET_DEST (x)) == var))
2396 && (GET_CODE (SET_SRC (x)) == REG
2397 || (GET_CODE (SET_SRC (x)) == SUBREG
2398 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2399 && GET_MODE (var) == promoted_mode
2400 && x == single_set (insn))
2404 if (GET_CODE (SET_DEST (x)) == SUBREG)
2405 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn,
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 (NEXT_INSN (pat) != NULL_RTX)
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);
2432 PATTERN (insn) = PATTERN (pat);
2437 /* Otherwise, storing into VAR must be handled specially
2438 by storing into a temporary and copying that into VAR
2439 with a new insn after this one. Note that this case
2440 will be used when storing into a promoted scalar since
2441 the insn will now have different modes on the input
2442 and output and hence will be invalid (except for the case
2443 of setting it to a constant, which does not need any
2444 change if it is valid). We generate extra code in that case,
2445 but combine.c will eliminate it. */
2450 rtx fixeddest = SET_DEST (x);
2451 enum machine_mode temp_mode;
2453 /* STRICT_LOW_PART can be discarded, around a MEM. */
2454 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2455 fixeddest = XEXP (fixeddest, 0);
2456 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2457 if (GET_CODE (fixeddest) == SUBREG)
2459 fixeddest = fixup_memory_subreg (fixeddest, insn,
2461 temp_mode = GET_MODE (fixeddest);
2465 fixeddest = fixup_stack_1 (fixeddest, insn);
2466 temp_mode = promoted_mode;
2469 temp = gen_reg_rtx (temp_mode);
2471 emit_insn_after (gen_move_insn (fixeddest,
2472 gen_lowpart (GET_MODE (fixeddest),
2476 SET_DEST (x) = temp;
2484 /* Nothing special about this RTX; fix its operands. */
2486 fmt = GET_RTX_FORMAT (code);
2487 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2490 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements,
2492 else if (fmt[i] == 'E')
2495 for (j = 0; j < XVECLEN (x, i); j++)
2496 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2497 insn, replacements, no_share);
2502 /* Previously, X had the form (SUBREG:m1 (REG:PROMOTED_MODE ...)).
2503 The REG was placed on the stack, so X now has the form (SUBREG:m1
2506 Return an rtx (MEM:m1 newaddr) which is equivalent. If any insns
2507 must be emitted to compute NEWADDR, put them before INSN.
2509 UNCRITICAL nonzero means accept paradoxical subregs.
2510 This is used for subregs found inside REG_NOTES. */
2513 fixup_memory_subreg (x, insn, promoted_mode, uncritical)
2516 enum machine_mode promoted_mode;
2520 rtx mem = SUBREG_REG (x);
2521 rtx addr = XEXP (mem, 0);
2522 enum machine_mode mode = GET_MODE (x);
2525 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2526 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (mem)) && ! uncritical)
2529 offset = SUBREG_BYTE (x);
2530 if (BYTES_BIG_ENDIAN)
2531 /* If the PROMOTED_MODE is wider than the mode of the MEM, adjust
2532 the offset so that it points to the right location within the
2534 offset -= (GET_MODE_SIZE (promoted_mode) - GET_MODE_SIZE (GET_MODE (mem)));
2536 if (!flag_force_addr
2537 && memory_address_p (mode, plus_constant (addr, offset)))
2538 /* Shortcut if no insns need be emitted. */
2539 return adjust_address (mem, mode, offset);
2542 result = adjust_address (mem, mode, offset);
2546 emit_insn_before (seq, insn);
2550 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2551 Replace subexpressions of X in place.
2552 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2553 Otherwise return X, with its contents possibly altered.
2555 INSN, PROMOTED_MODE and UNCRITICAL are as for
2556 fixup_memory_subreg. */
2559 walk_fixup_memory_subreg (x, insn, promoted_mode, uncritical)
2562 enum machine_mode promoted_mode;
2572 code = GET_CODE (x);
2574 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2575 return fixup_memory_subreg (x, insn, promoted_mode, uncritical);
2577 /* Nothing special about this RTX; fix its operands. */
2579 fmt = GET_RTX_FORMAT (code);
2580 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2583 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn,
2584 promoted_mode, uncritical);
2585 else if (fmt[i] == 'E')
2588 for (j = 0; j < XVECLEN (x, i); j++)
2590 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn,
2591 promoted_mode, uncritical);
2597 /* For each memory ref within X, if it refers to a stack slot
2598 with an out of range displacement, put the address in a temp register
2599 (emitting new insns before INSN to load these registers)
2600 and alter the memory ref to use that register.
2601 Replace each such MEM rtx with a copy, to avoid clobberage. */
2604 fixup_stack_1 (x, insn)
2609 RTX_CODE code = GET_CODE (x);
2614 rtx ad = XEXP (x, 0);
2615 /* If we have address of a stack slot but it's not valid
2616 (displacement is too large), compute the sum in a register. */
2617 if (GET_CODE (ad) == PLUS
2618 && GET_CODE (XEXP (ad, 0)) == REG
2619 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2620 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2621 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2622 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2623 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2625 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2626 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2627 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2628 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2631 if (memory_address_p (GET_MODE (x), ad))
2635 temp = copy_to_reg (ad);
2638 emit_insn_before (seq, insn);
2639 return replace_equiv_address (x, temp);
2644 fmt = GET_RTX_FORMAT (code);
2645 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2648 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2649 else if (fmt[i] == 'E')
2652 for (j = 0; j < XVECLEN (x, i); j++)
2653 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2659 /* Optimization: a bit-field instruction whose field
2660 happens to be a byte or halfword in memory
2661 can be changed to a move instruction.
2663 We call here when INSN is an insn to examine or store into a bit-field.
2664 BODY is the SET-rtx to be altered.
2666 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2667 (Currently this is called only from function.c, and EQUIV_MEM
2671 optimize_bit_field (body, insn, equiv_mem)
2679 enum machine_mode mode;
2681 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2682 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2683 bitfield = SET_DEST (body), destflag = 1;
2685 bitfield = SET_SRC (body), destflag = 0;
2687 /* First check that the field being stored has constant size and position
2688 and is in fact a byte or halfword suitably aligned. */
2690 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2691 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2692 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2694 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2698 /* Now check that the containing word is memory, not a register,
2699 and that it is safe to change the machine mode. */
2701 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2702 memref = XEXP (bitfield, 0);
2703 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2705 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2706 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2707 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2708 memref = SUBREG_REG (XEXP (bitfield, 0));
2709 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2711 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2712 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2715 && ! mode_dependent_address_p (XEXP (memref, 0))
2716 && ! MEM_VOLATILE_P (memref))
2718 /* Now adjust the address, first for any subreg'ing
2719 that we are now getting rid of,
2720 and then for which byte of the word is wanted. */
2722 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2725 /* Adjust OFFSET to count bits from low-address byte. */
2726 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2727 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2728 - offset - INTVAL (XEXP (bitfield, 1)));
2730 /* Adjust OFFSET to count bytes from low-address byte. */
2731 offset /= BITS_PER_UNIT;
2732 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2734 offset += (SUBREG_BYTE (XEXP (bitfield, 0))
2735 / UNITS_PER_WORD) * UNITS_PER_WORD;
2736 if (BYTES_BIG_ENDIAN)
2737 offset -= (MIN (UNITS_PER_WORD,
2738 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2739 - MIN (UNITS_PER_WORD,
2740 GET_MODE_SIZE (GET_MODE (memref))));
2744 memref = adjust_address (memref, mode, offset);
2745 insns = get_insns ();
2747 emit_insn_before (insns, insn);
2749 /* Store this memory reference where
2750 we found the bit field reference. */
2754 validate_change (insn, &SET_DEST (body), memref, 1);
2755 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2757 rtx src = SET_SRC (body);
2758 while (GET_CODE (src) == SUBREG
2759 && SUBREG_BYTE (src) == 0)
2760 src = SUBREG_REG (src);
2761 if (GET_MODE (src) != GET_MODE (memref))
2762 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2763 validate_change (insn, &SET_SRC (body), src, 1);
2765 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2766 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2767 /* This shouldn't happen because anything that didn't have
2768 one of these modes should have got converted explicitly
2769 and then referenced through a subreg.
2770 This is so because the original bit-field was
2771 handled by agg_mode and so its tree structure had
2772 the same mode that memref now has. */
2777 rtx dest = SET_DEST (body);
2779 while (GET_CODE (dest) == SUBREG
2780 && SUBREG_BYTE (dest) == 0
2781 && (GET_MODE_CLASS (GET_MODE (dest))
2782 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2783 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2785 dest = SUBREG_REG (dest);
2787 validate_change (insn, &SET_DEST (body), dest, 1);
2789 if (GET_MODE (dest) == GET_MODE (memref))
2790 validate_change (insn, &SET_SRC (body), memref, 1);
2793 /* Convert the mem ref to the destination mode. */
2794 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2797 convert_move (newreg, memref,
2798 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2802 validate_change (insn, &SET_SRC (body), newreg, 1);
2806 /* See if we can convert this extraction or insertion into
2807 a simple move insn. We might not be able to do so if this
2808 was, for example, part of a PARALLEL.
2810 If we succeed, write out any needed conversions. If we fail,
2811 it is hard to guess why we failed, so don't do anything
2812 special; just let the optimization be suppressed. */
2814 if (apply_change_group () && seq)
2815 emit_insn_before (seq, insn);
2820 /* These routines are responsible for converting virtual register references
2821 to the actual hard register references once RTL generation is complete.
2823 The following four variables are used for communication between the
2824 routines. They contain the offsets of the virtual registers from their
2825 respective hard registers. */
2827 static int in_arg_offset;
2828 static int var_offset;
2829 static int dynamic_offset;
2830 static int out_arg_offset;
2831 static int cfa_offset;
2833 /* In most machines, the stack pointer register is equivalent to the bottom
2836 #ifndef STACK_POINTER_OFFSET
2837 #define STACK_POINTER_OFFSET 0
2840 /* If not defined, pick an appropriate default for the offset of dynamically
2841 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2842 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2844 #ifndef STACK_DYNAMIC_OFFSET
2846 /* The bottom of the stack points to the actual arguments. If
2847 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2848 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2849 stack space for register parameters is not pushed by the caller, but
2850 rather part of the fixed stack areas and hence not included in
2851 `current_function_outgoing_args_size'. Nevertheless, we must allow
2852 for it when allocating stack dynamic objects. */
2854 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2855 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2856 ((ACCUMULATE_OUTGOING_ARGS \
2857 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2858 + (STACK_POINTER_OFFSET)) \
2861 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2862 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2863 + (STACK_POINTER_OFFSET))
2867 /* On most machines, the CFA coincides with the first incoming parm. */
2869 #ifndef ARG_POINTER_CFA_OFFSET
2870 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2873 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just had its
2874 address taken. DECL is the decl or SAVE_EXPR for the object stored in the
2875 register, for later use if we do need to force REG into the stack. REG is
2876 overwritten by the MEM like in put_reg_into_stack. */
2879 gen_mem_addressof (reg, decl)
2883 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2886 /* Calculate this before we start messing with decl's RTL. */
2887 HOST_WIDE_INT set = decl ? get_alias_set (decl) : 0;
2889 /* If the original REG was a user-variable, then so is the REG whose
2890 address is being taken. Likewise for unchanging. */
2891 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2892 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2894 PUT_CODE (reg, MEM);
2895 MEM_ATTRS (reg) = 0;
2900 tree type = TREE_TYPE (decl);
2901 enum machine_mode decl_mode
2902 = (DECL_P (decl) ? DECL_MODE (decl) : TYPE_MODE (TREE_TYPE (decl)));
2903 rtx decl_rtl = (TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl)
2904 : DECL_RTL_IF_SET (decl));
2906 PUT_MODE (reg, decl_mode);
2908 /* Clear DECL_RTL momentarily so functions below will work
2909 properly, then set it again. */
2910 if (DECL_P (decl) && decl_rtl == reg)
2911 SET_DECL_RTL (decl, 0);
2913 set_mem_attributes (reg, decl, 1);
2914 set_mem_alias_set (reg, set);
2916 if (DECL_P (decl) && decl_rtl == reg)
2917 SET_DECL_RTL (decl, reg);
2919 if (TREE_USED (decl) || (DECL_P (decl) && DECL_INITIAL (decl) != 0))
2920 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), reg, 0);
2923 fixup_var_refs (reg, GET_MODE (reg), 0, reg, 0);
2928 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2931 flush_addressof (decl)
2934 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2935 && DECL_RTL (decl) != 0
2936 && GET_CODE (DECL_RTL (decl)) == MEM
2937 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2938 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2939 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2942 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2945 put_addressof_into_stack (r, ht)
2950 int volatile_p, used_p;
2952 rtx reg = XEXP (r, 0);
2954 if (GET_CODE (reg) != REG)
2957 decl = ADDRESSOF_DECL (r);
2960 type = TREE_TYPE (decl);
2961 volatile_p = (TREE_CODE (decl) != SAVE_EXPR
2962 && TREE_THIS_VOLATILE (decl));
2963 used_p = (TREE_USED (decl)
2964 || (DECL_P (decl) && DECL_INITIAL (decl) != 0));
2973 put_reg_into_stack (0, reg, type, GET_MODE (reg), GET_MODE (reg),
2974 volatile_p, ADDRESSOF_REGNO (r), used_p, ht);
2977 /* List of replacements made below in purge_addressof_1 when creating
2978 bitfield insertions. */
2979 static rtx purge_bitfield_addressof_replacements;
2981 /* List of replacements made below in purge_addressof_1 for patterns
2982 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2983 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2984 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2985 enough in complex cases, e.g. when some field values can be
2986 extracted by usage MEM with narrower mode. */
2987 static rtx purge_addressof_replacements;
2989 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2990 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2991 the stack. If the function returns FALSE then the replacement could not
2995 purge_addressof_1 (loc, insn, force, store, ht)
3007 /* Re-start here to avoid recursion in common cases. */
3014 code = GET_CODE (x);
3016 /* If we don't return in any of the cases below, we will recurse inside
3017 the RTX, which will normally result in any ADDRESSOF being forced into
3021 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1, ht);
3022 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0, ht);
3025 else if (code == ADDRESSOF)
3029 if (GET_CODE (XEXP (x, 0)) != MEM)
3030 put_addressof_into_stack (x, ht);
3032 /* We must create a copy of the rtx because it was created by
3033 overwriting a REG rtx which is always shared. */
3034 sub = copy_rtx (XEXP (XEXP (x, 0), 0));
3035 if (validate_change (insn, loc, sub, 0)
3036 || validate_replace_rtx (x, sub, insn))
3040 sub = force_operand (sub, NULL_RTX);
3041 if (! validate_change (insn, loc, sub, 0)
3042 && ! validate_replace_rtx (x, sub, insn))
3045 insns = get_insns ();
3047 emit_insn_before (insns, insn);
3051 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
3053 rtx sub = XEXP (XEXP (x, 0), 0);
3055 if (GET_CODE (sub) == MEM)
3056 sub = adjust_address_nv (sub, GET_MODE (x), 0);
3057 else if (GET_CODE (sub) == REG
3058 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
3060 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
3062 int size_x, size_sub;
3066 /* When processing REG_NOTES look at the list of
3067 replacements done on the insn to find the register that X
3071 for (tem = purge_bitfield_addressof_replacements;
3073 tem = XEXP (XEXP (tem, 1), 1))
3074 if (rtx_equal_p (x, XEXP (tem, 0)))
3076 *loc = XEXP (XEXP (tem, 1), 0);
3080 /* See comment for purge_addressof_replacements. */
3081 for (tem = purge_addressof_replacements;
3083 tem = XEXP (XEXP (tem, 1), 1))
3084 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3086 rtx z = XEXP (XEXP (tem, 1), 0);
3088 if (GET_MODE (x) == GET_MODE (z)
3089 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
3090 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
3093 /* It can happen that the note may speak of things
3094 in a wider (or just different) mode than the
3095 code did. This is especially true of
3098 if (GET_CODE (z) == SUBREG && SUBREG_BYTE (z) == 0)
3101 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3102 && (GET_MODE_SIZE (GET_MODE (x))
3103 > GET_MODE_SIZE (GET_MODE (z))))
3105 /* This can occur as a result in invalid
3106 pointer casts, e.g. float f; ...
3107 *(long long int *)&f.
3108 ??? We could emit a warning here, but
3109 without a line number that wouldn't be
3111 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
3114 z = gen_lowpart (GET_MODE (x), z);
3120 /* Sometimes we may not be able to find the replacement. For
3121 example when the original insn was a MEM in a wider mode,
3122 and the note is part of a sign extension of a narrowed
3123 version of that MEM. Gcc testcase compile/990829-1.c can
3124 generate an example of this situation. Rather than complain
3125 we return false, which will prompt our caller to remove the
3130 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3131 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3133 /* Don't even consider working with paradoxical subregs,
3134 or the moral equivalent seen here. */
3135 if (size_x <= size_sub
3136 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3138 /* Do a bitfield insertion to mirror what would happen
3145 rtx p = PREV_INSN (insn);
3148 val = gen_reg_rtx (GET_MODE (x));
3149 if (! validate_change (insn, loc, val, 0))
3151 /* Discard the current sequence and put the
3152 ADDRESSOF on stack. */
3158 emit_insn_before (seq, insn);
3159 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3163 store_bit_field (sub, size_x, 0, GET_MODE (x),
3164 val, GET_MODE_SIZE (GET_MODE (sub)));
3166 /* Make sure to unshare any shared rtl that store_bit_field
3167 might have created. */
3168 unshare_all_rtl_again (get_insns ());
3172 p = emit_insn_after (seq, insn);
3173 if (NEXT_INSN (insn))
3174 compute_insns_for_mem (NEXT_INSN (insn),
3175 p ? NEXT_INSN (p) : NULL_RTX,
3180 rtx p = PREV_INSN (insn);
3183 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3184 GET_MODE (x), GET_MODE (x),
3185 GET_MODE_SIZE (GET_MODE (sub)));
3187 if (! validate_change (insn, loc, val, 0))
3189 /* Discard the current sequence and put the
3190 ADDRESSOF on stack. */
3197 emit_insn_before (seq, insn);
3198 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3202 /* Remember the replacement so that the same one can be done
3203 on the REG_NOTES. */
3204 purge_bitfield_addressof_replacements
3205 = gen_rtx_EXPR_LIST (VOIDmode, x,
3208 purge_bitfield_addressof_replacements));
3210 /* We replaced with a reg -- all done. */
3215 else if (validate_change (insn, loc, sub, 0))
3217 /* Remember the replacement so that the same one can be done
3218 on the REG_NOTES. */
3219 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3223 for (tem = purge_addressof_replacements;
3225 tem = XEXP (XEXP (tem, 1), 1))
3226 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3228 XEXP (XEXP (tem, 1), 0) = sub;
3231 purge_addressof_replacements
3232 = gen_rtx (EXPR_LIST, VOIDmode, XEXP (x, 0),
3233 gen_rtx_EXPR_LIST (VOIDmode, sub,
3234 purge_addressof_replacements));
3242 /* Scan all subexpressions. */
3243 fmt = GET_RTX_FORMAT (code);
3244 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3247 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0, ht);
3248 else if (*fmt == 'E')
3249 for (j = 0; j < XVECLEN (x, i); j++)
3250 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0, ht);
3256 /* Return a hash value for K, a REG. */
3259 insns_for_mem_hash (k)
3262 /* Use the address of the key for the hash value. */
3263 struct insns_for_mem_entry *m = (struct insns_for_mem_entry *) k;
3264 return htab_hash_pointer (m->key);
3267 /* Return nonzero if K1 and K2 (two REGs) are the same. */
3270 insns_for_mem_comp (k1, k2)
3274 struct insns_for_mem_entry *m1 = (struct insns_for_mem_entry *) k1;
3275 struct insns_for_mem_entry *m2 = (struct insns_for_mem_entry *) k2;
3276 return m1->key == m2->key;
3279 struct insns_for_mem_walk_info
3281 /* The hash table that we are using to record which INSNs use which
3285 /* The INSN we are currently processing. */
3288 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3289 to find the insns that use the REGs in the ADDRESSOFs. */
3293 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3294 that might be used in an ADDRESSOF expression, record this INSN in
3295 the hash table given by DATA (which is really a pointer to an
3296 insns_for_mem_walk_info structure). */
3299 insns_for_mem_walk (r, data)
3303 struct insns_for_mem_walk_info *ifmwi
3304 = (struct insns_for_mem_walk_info *) data;
3305 struct insns_for_mem_entry tmp;
3306 tmp.insns = NULL_RTX;
3308 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3309 && GET_CODE (XEXP (*r, 0)) == REG)
3312 tmp.key = XEXP (*r, 0);
3313 e = htab_find_slot (ifmwi->ht, &tmp, INSERT);
3316 *e = ggc_alloc (sizeof (tmp));
3317 memcpy (*e, &tmp, sizeof (tmp));
3320 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3322 struct insns_for_mem_entry *ifme;
3324 ifme = (struct insns_for_mem_entry *) htab_find (ifmwi->ht, &tmp);
3326 /* If we have not already recorded this INSN, do so now. Since
3327 we process the INSNs in order, we know that if we have
3328 recorded it it must be at the front of the list. */
3329 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3330 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3337 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3338 which REGs in HT. */
3341 compute_insns_for_mem (insns, last_insn, ht)
3347 struct insns_for_mem_walk_info ifmwi;
3350 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3351 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3355 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3359 /* Helper function for purge_addressof called through for_each_rtx.
3360 Returns true iff the rtl is an ADDRESSOF. */
3363 is_addressof (rtl, data)
3365 void *data ATTRIBUTE_UNUSED;
3367 return GET_CODE (*rtl) == ADDRESSOF;
3370 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3371 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3375 purge_addressof (insns)
3381 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3382 requires a fixup pass over the instruction stream to correct
3383 INSNs that depended on the REG being a REG, and not a MEM. But,
3384 these fixup passes are slow. Furthermore, most MEMs are not
3385 mentioned in very many instructions. So, we speed up the process
3386 by pre-calculating which REGs occur in which INSNs; that allows
3387 us to perform the fixup passes much more quickly. */
3388 ht = htab_create_ggc (1000, insns_for_mem_hash, insns_for_mem_comp, NULL);
3389 compute_insns_for_mem (insns, NULL_RTX, ht);
3391 for (insn = insns; insn; insn = NEXT_INSN (insn))
3394 if (! purge_addressof_1 (&PATTERN (insn), insn,
3395 asm_noperands (PATTERN (insn)) > 0, 0, ht))
3396 /* If we could not replace the ADDRESSOFs in the insn,
3397 something is wrong. */
3400 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, ht))
3402 /* If we could not replace the ADDRESSOFs in the insn's notes,
3403 we can just remove the offending notes instead. */
3406 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3408 /* If we find a REG_RETVAL note then the insn is a libcall.
3409 Such insns must have REG_EQUAL notes as well, in order
3410 for later passes of the compiler to work. So it is not
3411 safe to delete the notes here, and instead we abort. */
3412 if (REG_NOTE_KIND (note) == REG_RETVAL)
3414 if (for_each_rtx (¬e, is_addressof, NULL))
3415 remove_note (insn, note);
3421 purge_bitfield_addressof_replacements = 0;
3422 purge_addressof_replacements = 0;
3424 /* REGs are shared. purge_addressof will destructively replace a REG
3425 with a MEM, which creates shared MEMs.
3427 Unfortunately, the children of put_reg_into_stack assume that MEMs
3428 referring to the same stack slot are shared (fixup_var_refs and
3429 the associated hash table code).
3431 So, we have to do another unsharing pass after we have flushed any
3432 REGs that had their address taken into the stack.
3434 It may be worth tracking whether or not we converted any REGs into
3435 MEMs to avoid this overhead when it is not needed. */
3436 unshare_all_rtl_again (get_insns ());
3439 /* Convert a SET of a hard subreg to a set of the appropriate hard
3440 register. A subroutine of purge_hard_subreg_sets. */
3443 purge_single_hard_subreg_set (pattern)
3446 rtx reg = SET_DEST (pattern);
3447 enum machine_mode mode = GET_MODE (SET_DEST (pattern));
3450 if (GET_CODE (reg) == SUBREG && GET_CODE (SUBREG_REG (reg)) == REG
3451 && REGNO (SUBREG_REG (reg)) < FIRST_PSEUDO_REGISTER)
3453 offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)),
3454 GET_MODE (SUBREG_REG (reg)),
3457 reg = SUBREG_REG (reg);
3461 if (GET_CODE (reg) == REG && REGNO (reg) < FIRST_PSEUDO_REGISTER)
3463 reg = gen_rtx_REG (mode, REGNO (reg) + offset);
3464 SET_DEST (pattern) = reg;
3468 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The
3469 only such SETs that we expect to see are those left in because
3470 integrate can't handle sets of parts of a return value register.
3472 We don't use alter_subreg because we only want to eliminate subregs
3473 of hard registers. */
3476 purge_hard_subreg_sets (insn)
3479 for (; insn; insn = NEXT_INSN (insn))
3483 rtx pattern = PATTERN (insn);
3484 switch (GET_CODE (pattern))
3487 if (GET_CODE (SET_DEST (pattern)) == SUBREG)
3488 purge_single_hard_subreg_set (pattern);
3493 for (j = XVECLEN (pattern, 0) - 1; j >= 0; j--)
3495 rtx inner_pattern = XVECEXP (pattern, 0, j);
3496 if (GET_CODE (inner_pattern) == SET
3497 && GET_CODE (SET_DEST (inner_pattern)) == SUBREG)
3498 purge_single_hard_subreg_set (inner_pattern);
3509 /* Pass through the INSNS of function FNDECL and convert virtual register
3510 references to hard register references. */
3513 instantiate_virtual_regs (fndecl, insns)
3520 /* Compute the offsets to use for this function. */
3521 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3522 var_offset = STARTING_FRAME_OFFSET;
3523 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3524 out_arg_offset = STACK_POINTER_OFFSET;
3525 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl);
3527 /* Scan all variables and parameters of this function. For each that is
3528 in memory, instantiate all virtual registers if the result is a valid
3529 address. If not, we do it later. That will handle most uses of virtual
3530 regs on many machines. */
3531 instantiate_decls (fndecl, 1);
3533 /* Initialize recognition, indicating that volatile is OK. */
3536 /* Scan through all the insns, instantiating every virtual register still
3538 for (insn = insns; insn; insn = NEXT_INSN (insn))
3539 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3540 || GET_CODE (insn) == CALL_INSN)
3542 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3543 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3544 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
3545 if (GET_CODE (insn) == CALL_INSN)
3546 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn),
3550 /* Instantiate the stack slots for the parm registers, for later use in
3551 addressof elimination. */
3552 for (i = 0; i < max_parm_reg; ++i)
3553 if (parm_reg_stack_loc[i])
3554 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3556 /* Now instantiate the remaining register equivalences for debugging info.
3557 These will not be valid addresses. */
3558 instantiate_decls (fndecl, 0);
3560 /* Indicate that, from now on, assign_stack_local should use
3561 frame_pointer_rtx. */
3562 virtuals_instantiated = 1;
3565 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3566 all virtual registers in their DECL_RTL's.
3568 If VALID_ONLY, do this only if the resulting address is still valid.
3569 Otherwise, always do it. */
3572 instantiate_decls (fndecl, valid_only)
3578 /* Process all parameters of the function. */
3579 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3581 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3582 HOST_WIDE_INT size_rtl;
3584 instantiate_decl (DECL_RTL (decl), size, valid_only);
3586 /* If the parameter was promoted, then the incoming RTL mode may be
3587 larger than the declared type size. We must use the larger of
3589 size_rtl = GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl)));
3590 size = MAX (size_rtl, size);
3591 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3594 /* Now process all variables defined in the function or its subblocks. */
3595 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3598 /* Subroutine of instantiate_decls: Process all decls in the given
3599 BLOCK node and all its subblocks. */
3602 instantiate_decls_1 (let, valid_only)
3608 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3609 if (DECL_RTL_SET_P (t))
3610 instantiate_decl (DECL_RTL (t),
3611 int_size_in_bytes (TREE_TYPE (t)),
3614 /* Process all subblocks. */
3615 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3616 instantiate_decls_1 (t, valid_only);
3619 /* Subroutine of the preceding procedures: Given RTL representing a
3620 decl and the size of the object, do any instantiation required.
3622 If VALID_ONLY is nonzero, it means that the RTL should only be
3623 changed if the new address is valid. */
3626 instantiate_decl (x, size, valid_only)
3631 enum machine_mode mode;
3634 /* If this is not a MEM, no need to do anything. Similarly if the
3635 address is a constant or a register that is not a virtual register. */
3637 if (x == 0 || GET_CODE (x) != MEM)
3641 if (CONSTANT_P (addr)
3642 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3643 || (GET_CODE (addr) == REG
3644 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3645 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3648 /* If we should only do this if the address is valid, copy the address.
3649 We need to do this so we can undo any changes that might make the
3650 address invalid. This copy is unfortunate, but probably can't be
3654 addr = copy_rtx (addr);
3656 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3658 if (valid_only && size >= 0)
3660 unsigned HOST_WIDE_INT decl_size = size;
3662 /* Now verify that the resulting address is valid for every integer or
3663 floating-point mode up to and including SIZE bytes long. We do this
3664 since the object might be accessed in any mode and frame addresses
3667 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3668 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3669 mode = GET_MODE_WIDER_MODE (mode))
3670 if (! memory_address_p (mode, addr))
3673 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3674 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3675 mode = GET_MODE_WIDER_MODE (mode))
3676 if (! memory_address_p (mode, addr))
3680 /* Put back the address now that we have updated it and we either know
3681 it is valid or we don't care whether it is valid. */
3686 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
3687 is a virtual register, return the equivalent hard register and set the
3688 offset indirectly through the pointer. Otherwise, return 0. */
3691 instantiate_new_reg (x, poffset)
3693 HOST_WIDE_INT *poffset;
3696 HOST_WIDE_INT offset;
3698 if (x == virtual_incoming_args_rtx)
3699 new = arg_pointer_rtx, offset = in_arg_offset;
3700 else if (x == virtual_stack_vars_rtx)
3701 new = frame_pointer_rtx, offset = var_offset;
3702 else if (x == virtual_stack_dynamic_rtx)
3703 new = stack_pointer_rtx, offset = dynamic_offset;
3704 else if (x == virtual_outgoing_args_rtx)
3705 new = stack_pointer_rtx, offset = out_arg_offset;
3706 else if (x == virtual_cfa_rtx)
3707 new = arg_pointer_rtx, offset = cfa_offset;
3715 /* Given a pointer to a piece of rtx and an optional pointer to the
3716 containing object, instantiate any virtual registers present in it.
3718 If EXTRA_INSNS, we always do the replacement and generate
3719 any extra insns before OBJECT. If it zero, we do nothing if replacement
3722 Return 1 if we either had nothing to do or if we were able to do the
3723 needed replacement. Return 0 otherwise; we only return zero if
3724 EXTRA_INSNS is zero.
3726 We first try some simple transformations to avoid the creation of extra
3730 instantiate_virtual_regs_1 (loc, object, extra_insns)
3738 HOST_WIDE_INT offset = 0;
3744 /* Re-start here to avoid recursion in common cases. */
3751 code = GET_CODE (x);
3753 /* Check for some special cases. */
3771 /* We are allowed to set the virtual registers. This means that
3772 the actual register should receive the source minus the
3773 appropriate offset. This is used, for example, in the handling
3774 of non-local gotos. */
3775 if ((new = instantiate_new_reg (SET_DEST (x), &offset)) != 0)
3777 rtx src = SET_SRC (x);
3779 /* We are setting the register, not using it, so the relevant
3780 offset is the negative of the offset to use were we using
3783 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3785 /* The only valid sources here are PLUS or REG. Just do
3786 the simplest possible thing to handle them. */
3787 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3791 if (GET_CODE (src) != REG)
3792 temp = force_operand (src, NULL_RTX);
3795 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3799 emit_insn_before (seq, object);
3802 if (! validate_change (object, &SET_SRC (x), temp, 0)
3809 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3814 /* Handle special case of virtual register plus constant. */
3815 if (CONSTANT_P (XEXP (x, 1)))
3817 rtx old, new_offset;
3819 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3820 if (GET_CODE (XEXP (x, 0)) == PLUS)
3822 if ((new = instantiate_new_reg (XEXP (XEXP (x, 0), 0), &offset)))
3824 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3826 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3835 #ifdef POINTERS_EXTEND_UNSIGNED
3836 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
3837 we can commute the PLUS and SUBREG because pointers into the
3838 frame are well-behaved. */
3839 else if (GET_CODE (XEXP (x, 0)) == SUBREG && GET_MODE (x) == ptr_mode
3840 && GET_CODE (XEXP (x, 1)) == CONST_INT
3842 = instantiate_new_reg (SUBREG_REG (XEXP (x, 0)),
3844 && validate_change (object, loc,
3845 plus_constant (gen_lowpart (ptr_mode,
3848 + INTVAL (XEXP (x, 1))),
3852 else if ((new = instantiate_new_reg (XEXP (x, 0), &offset)) == 0)
3854 /* We know the second operand is a constant. Unless the
3855 first operand is a REG (which has been already checked),
3856 it needs to be checked. */
3857 if (GET_CODE (XEXP (x, 0)) != REG)
3865 new_offset = plus_constant (XEXP (x, 1), offset);
3867 /* If the new constant is zero, try to replace the sum with just
3869 if (new_offset == const0_rtx
3870 && validate_change (object, loc, new, 0))
3873 /* Next try to replace the register and new offset.
3874 There are two changes to validate here and we can't assume that
3875 in the case of old offset equals new just changing the register
3876 will yield a valid insn. In the interests of a little efficiency,
3877 however, we only call validate change once (we don't queue up the
3878 changes and then call apply_change_group). */
3882 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3883 : (XEXP (x, 0) = new,
3884 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3892 /* Otherwise copy the new constant into a register and replace
3893 constant with that register. */
3894 temp = gen_reg_rtx (Pmode);
3896 if (validate_change (object, &XEXP (x, 1), temp, 0))
3897 emit_insn_before (gen_move_insn (temp, new_offset), object);
3900 /* If that didn't work, replace this expression with a
3901 register containing the sum. */
3904 new = gen_rtx_PLUS (Pmode, new, new_offset);
3907 temp = force_operand (new, NULL_RTX);
3911 emit_insn_before (seq, object);
3912 if (! validate_change (object, loc, temp, 0)
3913 && ! validate_replace_rtx (x, temp, object))
3921 /* Fall through to generic two-operand expression case. */
3927 case DIV: case UDIV:
3928 case MOD: case UMOD:
3929 case AND: case IOR: case XOR:
3930 case ROTATERT: case ROTATE:
3931 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3933 case GE: case GT: case GEU: case GTU:
3934 case LE: case LT: case LEU: case LTU:
3935 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3936 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3941 /* Most cases of MEM that convert to valid addresses have already been
3942 handled by our scan of decls. The only special handling we
3943 need here is to make a copy of the rtx to ensure it isn't being
3944 shared if we have to change it to a pseudo.
3946 If the rtx is a simple reference to an address via a virtual register,
3947 it can potentially be shared. In such cases, first try to make it
3948 a valid address, which can also be shared. Otherwise, copy it and
3951 First check for common cases that need no processing. These are
3952 usually due to instantiation already being done on a previous instance
3956 if (CONSTANT_ADDRESS_P (temp)
3957 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3958 || temp == arg_pointer_rtx
3960 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3961 || temp == hard_frame_pointer_rtx
3963 || temp == frame_pointer_rtx)
3966 if (GET_CODE (temp) == PLUS
3967 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3968 && (XEXP (temp, 0) == frame_pointer_rtx
3969 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3970 || XEXP (temp, 0) == hard_frame_pointer_rtx
3972 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3973 || XEXP (temp, 0) == arg_pointer_rtx
3978 if (temp == virtual_stack_vars_rtx
3979 || temp == virtual_incoming_args_rtx
3980 || (GET_CODE (temp) == PLUS
3981 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3982 && (XEXP (temp, 0) == virtual_stack_vars_rtx
3983 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
3985 /* This MEM may be shared. If the substitution can be done without
3986 the need to generate new pseudos, we want to do it in place
3987 so all copies of the shared rtx benefit. The call below will
3988 only make substitutions if the resulting address is still
3991 Note that we cannot pass X as the object in the recursive call
3992 since the insn being processed may not allow all valid
3993 addresses. However, if we were not passed on object, we can
3994 only modify X without copying it if X will have a valid
3997 ??? Also note that this can still lose if OBJECT is an insn that
3998 has less restrictions on an address that some other insn.
3999 In that case, we will modify the shared address. This case
4000 doesn't seem very likely, though. One case where this could
4001 happen is in the case of a USE or CLOBBER reference, but we
4002 take care of that below. */
4004 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
4005 object ? object : x, 0))
4008 /* Otherwise make a copy and process that copy. We copy the entire
4009 RTL expression since it might be a PLUS which could also be
4011 *loc = x = copy_rtx (x);
4014 /* Fall through to generic unary operation case. */
4017 case STRICT_LOW_PART:
4019 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
4020 case SIGN_EXTEND: case ZERO_EXTEND:
4021 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
4022 case FLOAT: case FIX:
4023 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
4028 case POPCOUNT: case PARITY:
4029 /* These case either have just one operand or we know that we need not
4030 check the rest of the operands. */
4036 /* If the operand is a MEM, see if the change is a valid MEM. If not,
4037 go ahead and make the invalid one, but do it to a copy. For a REG,
4038 just make the recursive call, since there's no chance of a problem. */
4040 if ((GET_CODE (XEXP (x, 0)) == MEM
4041 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
4043 || (GET_CODE (XEXP (x, 0)) == REG
4044 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
4047 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
4052 /* Try to replace with a PLUS. If that doesn't work, compute the sum
4053 in front of this insn and substitute the temporary. */
4054 if ((new = instantiate_new_reg (x, &offset)) != 0)
4056 temp = plus_constant (new, offset);
4057 if (!validate_change (object, loc, temp, 0))
4063 temp = force_operand (temp, NULL_RTX);
4067 emit_insn_before (seq, object);
4068 if (! validate_change (object, loc, temp, 0)
4069 && ! validate_replace_rtx (x, temp, object))
4077 if (GET_CODE (XEXP (x, 0)) == REG)
4080 else if (GET_CODE (XEXP (x, 0)) == MEM)
4082 /* If we have a (addressof (mem ..)), do any instantiation inside
4083 since we know we'll be making the inside valid when we finally
4084 remove the ADDRESSOF. */
4085 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
4094 /* Scan all subexpressions. */
4095 fmt = GET_RTX_FORMAT (code);
4096 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
4099 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
4102 else if (*fmt == 'E')
4103 for (j = 0; j < XVECLEN (x, i); j++)
4104 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
4111 /* Optimization: assuming this function does not receive nonlocal gotos,
4112 delete the handlers for such, as well as the insns to establish
4113 and disestablish them. */
4119 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4121 /* Delete the handler by turning off the flag that would
4122 prevent jump_optimize from deleting it.
4123 Also permit deletion of the nonlocal labels themselves
4124 if nothing local refers to them. */
4125 if (GET_CODE (insn) == CODE_LABEL)
4129 LABEL_PRESERVE_P (insn) = 0;
4131 /* Remove it from the nonlocal_label list, to avoid confusing
4133 for (t = nonlocal_labels, last_t = 0; t;
4134 last_t = t, t = TREE_CHAIN (t))
4135 if (DECL_RTL (TREE_VALUE (t)) == insn)
4140 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
4142 TREE_CHAIN (last_t) = TREE_CHAIN (t);
4145 if (GET_CODE (insn) == INSN)
4149 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
4150 if (reg_mentioned_p (t, PATTERN (insn)))
4156 || (nonlocal_goto_stack_level != 0
4157 && reg_mentioned_p (nonlocal_goto_stack_level,
4159 delete_related_insns (insn);
4164 /* Return the first insn following those generated by `assign_parms'. */
4167 get_first_nonparm_insn ()
4170 return NEXT_INSN (last_parm_insn);
4171 return get_insns ();
4174 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4175 This means a type for which function calls must pass an address to the
4176 function or get an address back from the function.
4177 EXP may be a type node or an expression (whose type is tested). */
4180 aggregate_value_p (exp)
4183 int i, regno, nregs;
4186 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4188 if (TREE_CODE (type) == VOID_TYPE)
4190 if (RETURN_IN_MEMORY (type))
4192 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4193 and thus can't be returned in registers. */
4194 if (TREE_ADDRESSABLE (type))
4196 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4198 /* Make sure we have suitable call-clobbered regs to return
4199 the value in; if not, we must return it in memory. */
4200 reg = hard_function_value (type, 0, 0);
4202 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4204 if (GET_CODE (reg) != REG)
4207 regno = REGNO (reg);
4208 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
4209 for (i = 0; i < nregs; i++)
4210 if (! call_used_regs[regno + i])
4215 /* Assign RTL expressions to the function's parameters.
4216 This may involve copying them into registers and using
4217 those registers as the RTL for them. */
4220 assign_parms (fndecl)
4226 CUMULATIVE_ARGS args_so_far;
4227 enum machine_mode promoted_mode, passed_mode;
4228 enum machine_mode nominal_mode, promoted_nominal_mode;
4230 /* Total space needed so far for args on the stack,
4231 given as a constant and a tree-expression. */
4232 struct args_size stack_args_size;
4233 tree fntype = TREE_TYPE (fndecl);
4234 tree fnargs = DECL_ARGUMENTS (fndecl);
4235 /* This is used for the arg pointer when referring to stack args. */
4236 rtx internal_arg_pointer;
4237 /* This is a dummy PARM_DECL that we used for the function result if
4238 the function returns a structure. */
4239 tree function_result_decl = 0;
4240 #ifdef SETUP_INCOMING_VARARGS
4241 int varargs_setup = 0;
4243 rtx conversion_insns = 0;
4244 struct args_size alignment_pad;
4246 /* Nonzero if function takes extra anonymous args.
4247 This means the last named arg must be on the stack
4248 right before the anonymous ones. */
4250 = (TYPE_ARG_TYPES (fntype) != 0
4251 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4252 != void_type_node));
4254 current_function_stdarg = stdarg;
4256 /* If the reg that the virtual arg pointer will be translated into is
4257 not a fixed reg or is the stack pointer, make a copy of the virtual
4258 arg pointer, and address parms via the copy. The frame pointer is
4259 considered fixed even though it is not marked as such.
4261 The second time through, simply use ap to avoid generating rtx. */
4263 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4264 || ! (fixed_regs[ARG_POINTER_REGNUM]
4265 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4266 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4268 internal_arg_pointer = virtual_incoming_args_rtx;
4269 current_function_internal_arg_pointer = internal_arg_pointer;
4271 stack_args_size.constant = 0;
4272 stack_args_size.var = 0;
4274 /* If struct value address is treated as the first argument, make it so. */
4275 if (aggregate_value_p (DECL_RESULT (fndecl))
4276 && ! current_function_returns_pcc_struct
4277 && struct_value_incoming_rtx == 0)
4279 tree type = build_pointer_type (TREE_TYPE (fntype));
4281 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4283 DECL_ARG_TYPE (function_result_decl) = type;
4284 TREE_CHAIN (function_result_decl) = fnargs;
4285 fnargs = function_result_decl;
4288 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4289 parm_reg_stack_loc = (rtx *) ggc_alloc_cleared (max_parm_reg * sizeof (rtx));
4291 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4292 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4294 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, fndecl);
4297 /* We haven't yet found an argument that we must push and pretend the
4299 current_function_pretend_args_size = 0;
4301 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4303 struct args_size stack_offset;
4304 struct args_size arg_size;
4305 int passed_pointer = 0;
4306 int did_conversion = 0;
4307 tree passed_type = DECL_ARG_TYPE (parm);
4308 tree nominal_type = TREE_TYPE (parm);
4310 int last_named = 0, named_arg;
4312 /* Set LAST_NAMED if this is last named arg before last
4318 for (tem = TREE_CHAIN (parm); tem; tem = TREE_CHAIN (tem))
4319 if (DECL_NAME (tem))
4325 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4326 most machines, if this is a varargs/stdarg function, then we treat
4327 the last named arg as if it were anonymous too. */
4328 named_arg = STRICT_ARGUMENT_NAMING ? 1 : ! last_named;
4330 if (TREE_TYPE (parm) == error_mark_node
4331 /* This can happen after weird syntax errors
4332 or if an enum type is defined among the parms. */
4333 || TREE_CODE (parm) != PARM_DECL
4334 || passed_type == NULL)
4336 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx));
4337 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4338 TREE_USED (parm) = 1;
4342 /* Find mode of arg as it is passed, and mode of arg
4343 as it should be during execution of this function. */
4344 passed_mode = TYPE_MODE (passed_type);
4345 nominal_mode = TYPE_MODE (nominal_type);
4347 /* If the parm's mode is VOID, its value doesn't matter,
4348 and avoid the usual things like emit_move_insn that could crash. */
4349 if (nominal_mode == VOIDmode)
4351 SET_DECL_RTL (parm, const0_rtx);
4352 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4356 /* If the parm is to be passed as a transparent union, use the
4357 type of the first field for the tests below. We have already
4358 verified that the modes are the same. */
4359 if (DECL_TRANSPARENT_UNION (parm)
4360 || (TREE_CODE (passed_type) == UNION_TYPE
4361 && TYPE_TRANSPARENT_UNION (passed_type)))
4362 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4364 /* See if this arg was passed by invisible reference. It is if
4365 it is an object whose size depends on the contents of the
4366 object itself or if the machine requires these objects be passed
4369 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
4370 && contains_placeholder_p (TYPE_SIZE (passed_type)))
4371 || TREE_ADDRESSABLE (passed_type)
4372 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4373 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4374 passed_type, named_arg)
4378 passed_type = nominal_type = build_pointer_type (passed_type);
4380 passed_mode = nominal_mode = Pmode;
4382 /* See if the frontend wants to pass this by invisible reference. */
4383 else if (passed_type != nominal_type
4384 && POINTER_TYPE_P (passed_type)
4385 && TREE_TYPE (passed_type) == nominal_type)
4387 nominal_type = passed_type;
4389 passed_mode = nominal_mode = Pmode;
4392 promoted_mode = passed_mode;
4394 #ifdef PROMOTE_FUNCTION_ARGS
4395 /* Compute the mode in which the arg is actually extended to. */
4396 unsignedp = TREE_UNSIGNED (passed_type);
4397 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4400 /* Let machine desc say which reg (if any) the parm arrives in.
4401 0 means it arrives on the stack. */
4402 #ifdef FUNCTION_INCOMING_ARG
4403 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4404 passed_type, named_arg);
4406 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4407 passed_type, named_arg);
4410 if (entry_parm == 0)
4411 promoted_mode = passed_mode;
4413 #ifdef SETUP_INCOMING_VARARGS
4414 /* If this is the last named parameter, do any required setup for
4415 varargs or stdargs. We need to know about the case of this being an
4416 addressable type, in which case we skip the registers it
4417 would have arrived in.
4419 For stdargs, LAST_NAMED will be set for two parameters, the one that
4420 is actually the last named, and the dummy parameter. We only
4421 want to do this action once.
4423 Also, indicate when RTL generation is to be suppressed. */
4424 if (last_named && !varargs_setup)
4426 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
4427 current_function_pretend_args_size, 0);
4432 /* Determine parm's home in the stack,
4433 in case it arrives in the stack or we should pretend it did.
4435 Compute the stack position and rtx where the argument arrives
4438 There is one complexity here: If this was a parameter that would
4439 have been passed in registers, but wasn't only because it is
4440 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4441 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4442 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4443 0 as it was the previous time. */
4445 pretend_named = named_arg || PRETEND_OUTGOING_VARARGS_NAMED;
4446 locate_and_pad_parm (promoted_mode, passed_type,
4447 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4450 #ifdef FUNCTION_INCOMING_ARG
4451 FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4453 pretend_named) != 0,
4455 FUNCTION_ARG (args_so_far, promoted_mode,
4457 pretend_named) != 0,
4460 fndecl, &stack_args_size, &stack_offset, &arg_size,
4464 rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
4466 if (offset_rtx == const0_rtx)
4467 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4469 stack_parm = gen_rtx_MEM (promoted_mode,
4470 gen_rtx_PLUS (Pmode,
4471 internal_arg_pointer,
4474 set_mem_attributes (stack_parm, parm, 1);
4476 /* Set also REG_ATTRS if parameter was passed in a register. */
4478 set_reg_attrs_for_parm (entry_parm, stack_parm);
4481 /* If this parameter was passed both in registers and in the stack,
4482 use the copy on the stack. */
4483 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4486 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4487 /* If this parm was passed part in regs and part in memory,
4488 pretend it arrived entirely in memory
4489 by pushing the register-part onto the stack.
4491 In the special case of a DImode or DFmode that is split,
4492 we could put it together in a pseudoreg directly,
4493 but for now that's not worth bothering with. */
4497 int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4498 passed_type, named_arg);
4502 #if defined (REG_PARM_STACK_SPACE) && !defined (MAYBE_REG_PARM_STACK_SPACE)
4503 /* When REG_PARM_STACK_SPACE is nonzero, stack space for
4504 split parameters was allocated by our caller, so we
4505 won't be pushing it in the prolog. */
4506 if (REG_PARM_STACK_SPACE (fndecl) == 0)
4508 current_function_pretend_args_size
4509 = (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
4510 / (PARM_BOUNDARY / BITS_PER_UNIT)
4511 * (PARM_BOUNDARY / BITS_PER_UNIT));
4513 /* Handle calls that pass values in multiple non-contiguous
4514 locations. The Irix 6 ABI has examples of this. */
4515 if (GET_CODE (entry_parm) == PARALLEL)
4516 emit_group_store (validize_mem (stack_parm), entry_parm,
4517 int_size_in_bytes (TREE_TYPE (parm)));
4520 move_block_from_reg (REGNO (entry_parm),
4521 validize_mem (stack_parm), nregs,
4522 int_size_in_bytes (TREE_TYPE (parm)));
4524 entry_parm = stack_parm;
4529 /* If we didn't decide this parm came in a register,
4530 by default it came on the stack. */
4531 if (entry_parm == 0)
4532 entry_parm = stack_parm;
4534 /* Record permanently how this parm was passed. */
4535 DECL_INCOMING_RTL (parm) = entry_parm;
4537 /* If there is actually space on the stack for this parm,
4538 count it in stack_args_size; otherwise set stack_parm to 0
4539 to indicate there is no preallocated stack slot for the parm. */
4541 if (entry_parm == stack_parm
4542 || (GET_CODE (entry_parm) == PARALLEL
4543 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4544 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4545 /* On some machines, even if a parm value arrives in a register
4546 there is still an (uninitialized) stack slot allocated for it.
4548 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4549 whether this parameter already has a stack slot allocated,
4550 because an arg block exists only if current_function_args_size
4551 is larger than some threshold, and we haven't calculated that
4552 yet. So, for now, we just assume that stack slots never exist
4554 || REG_PARM_STACK_SPACE (fndecl) > 0
4558 stack_args_size.constant += arg_size.constant;
4560 ADD_PARM_SIZE (stack_args_size, arg_size.var);
4563 /* No stack slot was pushed for this parm. */
4566 /* Update info on where next arg arrives in registers. */
4568 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4569 passed_type, named_arg);
4571 /* If we can't trust the parm stack slot to be aligned enough
4572 for its ultimate type, don't use that slot after entry.
4573 We'll make another stack slot, if we need one. */
4575 unsigned int thisparm_boundary
4576 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4578 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4582 /* If parm was passed in memory, and we need to convert it on entry,
4583 don't store it back in that same slot. */
4585 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4588 /* When an argument is passed in multiple locations, we can't
4589 make use of this information, but we can save some copying if
4590 the whole argument is passed in a single register. */
4591 if (GET_CODE (entry_parm) == PARALLEL
4592 && nominal_mode != BLKmode && passed_mode != BLKmode)
4594 int i, len = XVECLEN (entry_parm, 0);
4596 for (i = 0; i < len; i++)
4597 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
4598 && GET_CODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) == REG
4599 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
4601 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
4603 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
4604 DECL_INCOMING_RTL (parm) = entry_parm;
4609 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4610 in the mode in which it arrives.
4611 STACK_PARM is an RTX for a stack slot where the parameter can live
4612 during the function (in case we want to put it there).
4613 STACK_PARM is 0 if no stack slot was pushed for it.
4615 Now output code if necessary to convert ENTRY_PARM to
4616 the type in which this function declares it,
4617 and store that result in an appropriate place,
4618 which may be a pseudo reg, may be STACK_PARM,
4619 or may be a local stack slot if STACK_PARM is 0.
4621 Set DECL_RTL to that place. */
4623 if (nominal_mode == BLKmode || GET_CODE (entry_parm) == PARALLEL)
4625 /* If a BLKmode arrives in registers, copy it to a stack slot.
4626 Handle calls that pass values in multiple non-contiguous
4627 locations. The Irix 6 ABI has examples of this. */
4628 if (GET_CODE (entry_parm) == REG
4629 || GET_CODE (entry_parm) == PARALLEL)
4632 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
4635 /* Note that we will be storing an integral number of words.
4636 So we have to be careful to ensure that we allocate an
4637 integral number of words. We do this below in the
4638 assign_stack_local if space was not allocated in the argument
4639 list. If it was, this will not work if PARM_BOUNDARY is not
4640 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4641 if it becomes a problem. */
4643 if (stack_parm == 0)
4646 = assign_stack_local (GET_MODE (entry_parm),
4648 set_mem_attributes (stack_parm, parm, 1);
4651 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4654 /* Handle calls that pass values in multiple non-contiguous
4655 locations. The Irix 6 ABI has examples of this. */
4656 if (GET_CODE (entry_parm) == PARALLEL)
4657 emit_group_store (validize_mem (stack_parm), entry_parm,
4658 int_size_in_bytes (TREE_TYPE (parm)));
4660 move_block_from_reg (REGNO (entry_parm),
4661 validize_mem (stack_parm),
4662 size_stored / UNITS_PER_WORD,
4663 int_size_in_bytes (TREE_TYPE (parm)));
4665 SET_DECL_RTL (parm, stack_parm);
4667 else if (! ((! optimize
4668 && ! DECL_REGISTER (parm))
4669 || TREE_SIDE_EFFECTS (parm)
4670 /* If -ffloat-store specified, don't put explicit
4671 float variables into registers. */
4672 || (flag_float_store
4673 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4674 /* Always assign pseudo to structure return or item passed
4675 by invisible reference. */
4676 || passed_pointer || parm == function_result_decl)
4678 /* Store the parm in a pseudoregister during the function, but we
4679 may need to do it in a wider mode. */
4682 unsigned int regno, regnoi = 0, regnor = 0;
4684 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4686 promoted_nominal_mode
4687 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4689 parmreg = gen_reg_rtx (promoted_nominal_mode);
4690 mark_user_reg (parmreg);
4692 /* If this was an item that we received a pointer to, set DECL_RTL
4696 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)),
4698 set_mem_attributes (x, parm, 1);
4699 SET_DECL_RTL (parm, x);
4703 SET_DECL_RTL (parm, parmreg);
4704 maybe_set_unchanging (DECL_RTL (parm), parm);
4707 /* Copy the value into the register. */
4708 if (nominal_mode != passed_mode
4709 || promoted_nominal_mode != promoted_mode)
4712 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4713 mode, by the caller. We now have to convert it to
4714 NOMINAL_MODE, if different. However, PARMREG may be in
4715 a different mode than NOMINAL_MODE if it is being stored
4718 If ENTRY_PARM is a hard register, it might be in a register
4719 not valid for operating in its mode (e.g., an odd-numbered
4720 register for a DFmode). In that case, moves are the only
4721 thing valid, so we can't do a convert from there. This
4722 occurs when the calling sequence allow such misaligned
4725 In addition, the conversion may involve a call, which could
4726 clobber parameters which haven't been copied to pseudo
4727 registers yet. Therefore, we must first copy the parm to
4728 a pseudo reg here, and save the conversion until after all
4729 parameters have been moved. */
4731 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4733 emit_move_insn (tempreg, validize_mem (entry_parm));
4735 push_to_sequence (conversion_insns);
4736 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4738 if (GET_CODE (tempreg) == SUBREG
4739 && GET_MODE (tempreg) == nominal_mode
4740 && GET_CODE (SUBREG_REG (tempreg)) == REG
4741 && nominal_mode == passed_mode
4742 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm)
4743 && GET_MODE_SIZE (GET_MODE (tempreg))
4744 < GET_MODE_SIZE (GET_MODE (entry_parm)))
4746 /* The argument is already sign/zero extended, so note it
4748 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
4749 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
4752 /* TREE_USED gets set erroneously during expand_assignment. */
4753 save_tree_used = TREE_USED (parm);
4754 expand_assignment (parm,
4755 make_tree (nominal_type, tempreg), 0, 0);
4756 TREE_USED (parm) = save_tree_used;
4757 conversion_insns = get_insns ();
4762 emit_move_insn (parmreg, validize_mem (entry_parm));
4764 /* If we were passed a pointer but the actual value
4765 can safely live in a register, put it in one. */
4766 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4767 /* If by-reference argument was promoted, demote it. */
4768 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
4770 && ! DECL_REGISTER (parm))
4771 || TREE_SIDE_EFFECTS (parm)
4772 /* If -ffloat-store specified, don't put explicit
4773 float variables into registers. */
4774 || (flag_float_store
4775 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))))
4777 /* We can't use nominal_mode, because it will have been set to
4778 Pmode above. We must use the actual mode of the parm. */
4779 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4780 mark_user_reg (parmreg);
4781 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
4783 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
4784 int unsigned_p = TREE_UNSIGNED (TREE_TYPE (parm));
4785 push_to_sequence (conversion_insns);
4786 emit_move_insn (tempreg, DECL_RTL (parm));
4788 convert_to_mode (GET_MODE (parmreg),
4791 emit_move_insn (parmreg, DECL_RTL (parm));
4792 conversion_insns = get_insns();
4797 emit_move_insn (parmreg, DECL_RTL (parm));
4798 SET_DECL_RTL (parm, parmreg);
4799 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4803 #ifdef FUNCTION_ARG_CALLEE_COPIES
4804 /* If we are passed an arg by reference and it is our responsibility
4805 to make a copy, do it now.
4806 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4807 original argument, so we must recreate them in the call to
4808 FUNCTION_ARG_CALLEE_COPIES. */
4809 /* ??? Later add code to handle the case that if the argument isn't
4810 modified, don't do the copy. */
4812 else if (passed_pointer
4813 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4814 TYPE_MODE (DECL_ARG_TYPE (parm)),
4815 DECL_ARG_TYPE (parm),
4817 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4820 tree type = DECL_ARG_TYPE (parm);
4822 /* This sequence may involve a library call perhaps clobbering
4823 registers that haven't been copied to pseudos yet. */
4825 push_to_sequence (conversion_insns);
4827 if (!COMPLETE_TYPE_P (type)
4828 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4829 /* This is a variable sized object. */
4830 copy = gen_rtx_MEM (BLKmode,
4831 allocate_dynamic_stack_space
4832 (expr_size (parm), NULL_RTX,
4833 TYPE_ALIGN (type)));
4835 copy = assign_stack_temp (TYPE_MODE (type),
4836 int_size_in_bytes (type), 1);
4837 set_mem_attributes (copy, parm, 1);
4839 store_expr (parm, copy, 0);
4840 emit_move_insn (parmreg, XEXP (copy, 0));
4841 conversion_insns = get_insns ();
4845 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4847 /* In any case, record the parm's desired stack location
4848 in case we later discover it must live in the stack.
4850 If it is a COMPLEX value, store the stack location for both
4853 if (GET_CODE (parmreg) == CONCAT)
4854 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4856 regno = REGNO (parmreg);
4858 if (regno >= max_parm_reg)
4861 int old_max_parm_reg = max_parm_reg;
4863 /* It's slow to expand this one register at a time,
4864 but it's also rare and we need max_parm_reg to be
4865 precisely correct. */
4866 max_parm_reg = regno + 1;
4867 new = (rtx *) ggc_realloc (parm_reg_stack_loc,
4868 max_parm_reg * sizeof (rtx));
4869 memset ((char *) (new + old_max_parm_reg), 0,
4870 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4871 parm_reg_stack_loc = new;
4874 if (GET_CODE (parmreg) == CONCAT)
4876 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
4878 regnor = REGNO (gen_realpart (submode, parmreg));
4879 regnoi = REGNO (gen_imagpart (submode, parmreg));
4881 if (stack_parm != 0)
4883 parm_reg_stack_loc[regnor]
4884 = gen_realpart (submode, stack_parm);
4885 parm_reg_stack_loc[regnoi]
4886 = gen_imagpart (submode, stack_parm);
4890 parm_reg_stack_loc[regnor] = 0;
4891 parm_reg_stack_loc[regnoi] = 0;
4895 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
4897 /* Mark the register as eliminable if we did no conversion
4898 and it was copied from memory at a fixed offset,
4899 and the arg pointer was not copied to a pseudo-reg.
4900 If the arg pointer is a pseudo reg or the offset formed
4901 an invalid address, such memory-equivalences
4902 as we make here would screw up life analysis for it. */
4903 if (nominal_mode == passed_mode
4906 && GET_CODE (stack_parm) == MEM
4907 && stack_offset.var == 0
4908 && reg_mentioned_p (virtual_incoming_args_rtx,
4909 XEXP (stack_parm, 0)))
4911 rtx linsn = get_last_insn ();
4914 /* Mark complex types separately. */
4915 if (GET_CODE (parmreg) == CONCAT)
4916 /* Scan backwards for the set of the real and
4918 for (sinsn = linsn; sinsn != 0;
4919 sinsn = prev_nonnote_insn (sinsn))
4921 set = single_set (sinsn);
4923 && SET_DEST (set) == regno_reg_rtx [regnoi])
4925 = gen_rtx_EXPR_LIST (REG_EQUIV,
4926 parm_reg_stack_loc[regnoi],
4929 && SET_DEST (set) == regno_reg_rtx [regnor])
4931 = gen_rtx_EXPR_LIST (REG_EQUIV,
4932 parm_reg_stack_loc[regnor],
4935 else if ((set = single_set (linsn)) != 0
4936 && SET_DEST (set) == parmreg)
4938 = gen_rtx_EXPR_LIST (REG_EQUIV,
4939 stack_parm, REG_NOTES (linsn));
4942 /* For pointer data type, suggest pointer register. */
4943 if (POINTER_TYPE_P (TREE_TYPE (parm)))
4944 mark_reg_pointer (parmreg,
4945 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
4947 /* If something wants our address, try to use ADDRESSOF. */
4948 if (TREE_ADDRESSABLE (parm))
4950 /* If we end up putting something into the stack,
4951 fixup_var_refs_insns will need to make a pass over
4952 all the instructions. It looks through the pending
4953 sequences -- but it can't see the ones in the
4954 CONVERSION_INSNS, if they're not on the sequence
4955 stack. So, we go back to that sequence, just so that
4956 the fixups will happen. */
4957 push_to_sequence (conversion_insns);
4958 put_var_into_stack (parm);
4959 conversion_insns = get_insns ();
4965 /* Value must be stored in the stack slot STACK_PARM
4966 during function execution. */
4968 if (promoted_mode != nominal_mode)
4970 /* Conversion is required. */
4971 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4973 emit_move_insn (tempreg, validize_mem (entry_parm));
4975 push_to_sequence (conversion_insns);
4976 entry_parm = convert_to_mode (nominal_mode, tempreg,
4977 TREE_UNSIGNED (TREE_TYPE (parm)));
4979 /* ??? This may need a big-endian conversion on sparc64. */
4980 stack_parm = adjust_address (stack_parm, nominal_mode, 0);
4982 conversion_insns = get_insns ();
4987 if (entry_parm != stack_parm)
4989 if (stack_parm == 0)
4992 = assign_stack_local (GET_MODE (entry_parm),
4993 GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
4994 set_mem_attributes (stack_parm, parm, 1);
4997 if (promoted_mode != nominal_mode)
4999 push_to_sequence (conversion_insns);
5000 emit_move_insn (validize_mem (stack_parm),
5001 validize_mem (entry_parm));
5002 conversion_insns = get_insns ();
5006 emit_move_insn (validize_mem (stack_parm),
5007 validize_mem (entry_parm));
5010 SET_DECL_RTL (parm, stack_parm);
5013 /* If this "parameter" was the place where we are receiving the
5014 function's incoming structure pointer, set up the result. */
5015 if (parm == function_result_decl)
5017 tree result = DECL_RESULT (fndecl);
5018 rtx addr = DECL_RTL (parm);
5021 #ifdef POINTERS_EXTEND_UNSIGNED
5022 if (GET_MODE (addr) != Pmode)
5023 addr = convert_memory_address (Pmode, addr);
5026 x = gen_rtx_MEM (DECL_MODE (result), addr);
5027 set_mem_attributes (x, result, 1);
5028 SET_DECL_RTL (result, x);
5032 /* Output all parameter conversion instructions (possibly including calls)
5033 now that all parameters have been copied out of hard registers. */
5034 emit_insn (conversion_insns);
5036 last_parm_insn = get_last_insn ();
5038 current_function_args_size = stack_args_size.constant;
5040 /* Adjust function incoming argument size for alignment and
5043 #ifdef REG_PARM_STACK_SPACE
5044 #ifndef MAYBE_REG_PARM_STACK_SPACE
5045 current_function_args_size = MAX (current_function_args_size,
5046 REG_PARM_STACK_SPACE (fndecl));
5050 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
5052 current_function_args_size
5053 = ((current_function_args_size + STACK_BYTES - 1)
5054 / STACK_BYTES) * STACK_BYTES;
5056 #ifdef ARGS_GROW_DOWNWARD
5057 current_function_arg_offset_rtx
5058 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
5059 : expand_expr (size_diffop (stack_args_size.var,
5060 size_int (-stack_args_size.constant)),
5061 NULL_RTX, VOIDmode, 0));
5063 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
5066 /* See how many bytes, if any, of its args a function should try to pop
5069 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
5070 current_function_args_size);
5072 /* For stdarg.h function, save info about
5073 regs and stack space used by the named args. */
5075 current_function_args_info = args_so_far;
5077 /* Set the rtx used for the function return value. Put this in its
5078 own variable so any optimizers that need this information don't have
5079 to include tree.h. Do this here so it gets done when an inlined
5080 function gets output. */
5082 current_function_return_rtx
5083 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
5084 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
5086 /* If scalar return value was computed in a pseudo-reg, or was a named
5087 return value that got dumped to the stack, copy that to the hard
5089 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
5091 tree decl_result = DECL_RESULT (fndecl);
5092 rtx decl_rtl = DECL_RTL (decl_result);
5094 if (REG_P (decl_rtl)
5095 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5096 : DECL_REGISTER (decl_result))
5100 #ifdef FUNCTION_OUTGOING_VALUE
5101 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
5104 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
5107 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
5108 /* The delay slot scheduler assumes that current_function_return_rtx
5109 holds the hard register containing the return value, not a
5110 temporary pseudo. */
5111 current_function_return_rtx = real_decl_rtl;
5116 /* Indicate whether REGNO is an incoming argument to the current function
5117 that was promoted to a wider mode. If so, return the RTX for the
5118 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5119 that REGNO is promoted from and whether the promotion was signed or
5122 #ifdef PROMOTE_FUNCTION_ARGS
5125 promoted_input_arg (regno, pmode, punsignedp)
5127 enum machine_mode *pmode;
5132 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
5133 arg = TREE_CHAIN (arg))
5134 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
5135 && REGNO (DECL_INCOMING_RTL (arg)) == regno
5136 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
5138 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
5139 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
5141 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
5142 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
5143 && mode != DECL_MODE (arg))
5145 *pmode = DECL_MODE (arg);
5146 *punsignedp = unsignedp;
5147 return DECL_INCOMING_RTL (arg);
5156 /* Compute the size and offset from the start of the stacked arguments for a
5157 parm passed in mode PASSED_MODE and with type TYPE.
5159 INITIAL_OFFSET_PTR points to the current offset into the stacked
5162 The starting offset and size for this parm are returned in *OFFSET_PTR
5163 and *ARG_SIZE_PTR, respectively.
5165 IN_REGS is nonzero if the argument will be passed in registers. It will
5166 never be set if REG_PARM_STACK_SPACE is not defined.
5168 FNDECL is the function in which the argument was defined.
5170 There are two types of rounding that are done. The first, controlled by
5171 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5172 list to be aligned to the specific boundary (in bits). This rounding
5173 affects the initial and starting offsets, but not the argument size.
5175 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5176 optionally rounds the size of the parm to PARM_BOUNDARY. The
5177 initial offset is not affected by this rounding, while the size always
5178 is and the starting offset may be. */
5180 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
5181 initial_offset_ptr is positive because locate_and_pad_parm's
5182 callers pass in the total size of args so far as
5183 initial_offset_ptr. arg_size_ptr is always positive. */
5186 locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
5187 initial_offset_ptr, offset_ptr, arg_size_ptr,
5189 enum machine_mode passed_mode;
5191 int in_regs ATTRIBUTE_UNUSED;
5192 tree fndecl ATTRIBUTE_UNUSED;
5193 struct args_size *initial_offset_ptr;
5194 struct args_size *offset_ptr;
5195 struct args_size *arg_size_ptr;
5196 struct args_size *alignment_pad;
5200 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5201 enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5202 int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5203 #ifdef ARGS_GROW_DOWNWARD
5207 #ifdef REG_PARM_STACK_SPACE
5208 /* If we have found a stack parm before we reach the end of the
5209 area reserved for registers, skip that area. */
5212 int reg_parm_stack_space = 0;
5214 #ifdef MAYBE_REG_PARM_STACK_SPACE
5215 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
5217 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5219 if (reg_parm_stack_space > 0)
5221 if (initial_offset_ptr->var)
5223 initial_offset_ptr->var
5224 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5225 ssize_int (reg_parm_stack_space));
5226 initial_offset_ptr->constant = 0;
5228 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5229 initial_offset_ptr->constant = reg_parm_stack_space;
5232 #endif /* REG_PARM_STACK_SPACE */
5234 arg_size_ptr->var = 0;
5235 arg_size_ptr->constant = 0;
5236 alignment_pad->var = 0;
5237 alignment_pad->constant = 0;
5239 #ifdef ARGS_GROW_DOWNWARD
5240 if (initial_offset_ptr->var)
5242 offset_ptr->constant = 0;
5243 offset_ptr->var = size_binop (MINUS_EXPR, ssize_int (0),
5244 initial_offset_ptr->var);
5248 offset_ptr->constant = -initial_offset_ptr->constant;
5249 offset_ptr->var = 0;
5252 if (where_pad != none
5253 && (!host_integerp (sizetree, 1)
5254 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5255 s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
5256 SUB_PARM_SIZE (*offset_ptr, s2);
5259 #ifdef REG_PARM_STACK_SPACE
5260 || REG_PARM_STACK_SPACE (fndecl) > 0
5263 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad);
5265 if (initial_offset_ptr->var)
5266 arg_size_ptr->var = size_binop (MINUS_EXPR,
5267 size_binop (MINUS_EXPR,
5269 initial_offset_ptr->var),
5273 arg_size_ptr->constant = (-initial_offset_ptr->constant
5274 - offset_ptr->constant);
5276 /* Pad_below needs the pre-rounded size to know how much to pad below.
5277 We only pad parameters which are not in registers as they have their
5278 padding done elsewhere. */
5279 if (where_pad == downward
5281 pad_below (offset_ptr, passed_mode, sizetree);
5283 #else /* !ARGS_GROW_DOWNWARD */
5285 #ifdef REG_PARM_STACK_SPACE
5286 || REG_PARM_STACK_SPACE (fndecl) > 0
5289 pad_to_arg_alignment (initial_offset_ptr, boundary, alignment_pad);
5290 *offset_ptr = *initial_offset_ptr;
5292 #ifdef PUSH_ROUNDING
5293 if (passed_mode != BLKmode)
5294 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5297 /* Pad_below needs the pre-rounded size to know how much to pad below
5298 so this must be done before rounding up. */
5299 if (where_pad == downward
5300 /* However, BLKmode args passed in regs have their padding done elsewhere.
5301 The stack slot must be able to hold the entire register. */
5302 && !(in_regs && passed_mode == BLKmode))
5303 pad_below (offset_ptr, passed_mode, sizetree);
5305 if (where_pad != none
5306 && (!host_integerp (sizetree, 1)
5307 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5308 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5310 ADD_PARM_SIZE (*arg_size_ptr, sizetree);
5311 #endif /* ARGS_GROW_DOWNWARD */
5314 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5315 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5318 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad)
5319 struct args_size *offset_ptr;
5321 struct args_size *alignment_pad;
5323 tree save_var = NULL_TREE;
5324 HOST_WIDE_INT save_constant = 0;
5326 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5328 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5330 save_var = offset_ptr->var;
5331 save_constant = offset_ptr->constant;
5334 alignment_pad->var = NULL_TREE;
5335 alignment_pad->constant = 0;
5337 if (boundary > BITS_PER_UNIT)
5339 if (offset_ptr->var)
5342 #ifdef ARGS_GROW_DOWNWARD
5347 (ARGS_SIZE_TREE (*offset_ptr),
5348 boundary / BITS_PER_UNIT);
5349 offset_ptr->constant = 0; /*?*/
5350 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5351 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5356 offset_ptr->constant =
5357 #ifdef ARGS_GROW_DOWNWARD
5358 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
5360 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
5362 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5363 alignment_pad->constant = offset_ptr->constant - save_constant;
5369 pad_below (offset_ptr, passed_mode, sizetree)
5370 struct args_size *offset_ptr;
5371 enum machine_mode passed_mode;
5374 if (passed_mode != BLKmode)
5376 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5377 offset_ptr->constant
5378 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5379 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5380 - GET_MODE_SIZE (passed_mode));
5384 if (TREE_CODE (sizetree) != INTEGER_CST
5385 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5387 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5388 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5390 ADD_PARM_SIZE (*offset_ptr, s2);
5391 SUB_PARM_SIZE (*offset_ptr, sizetree);
5396 /* Walk the tree of blocks describing the binding levels within a function
5397 and warn about uninitialized variables.
5398 This is done after calling flow_analysis and before global_alloc
5399 clobbers the pseudo-regs to hard regs. */
5402 uninitialized_vars_warning (block)
5406 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5408 if (warn_uninitialized
5409 && TREE_CODE (decl) == VAR_DECL
5410 /* These warnings are unreliable for and aggregates
5411 because assigning the fields one by one can fail to convince
5412 flow.c that the entire aggregate was initialized.
5413 Unions are troublesome because members may be shorter. */
5414 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5415 && DECL_RTL (decl) != 0
5416 && GET_CODE (DECL_RTL (decl)) == REG
5417 /* Global optimizations can make it difficult to determine if a
5418 particular variable has been initialized. However, a VAR_DECL
5419 with a nonzero DECL_INITIAL had an initializer, so do not
5420 claim it is potentially uninitialized.
5422 We do not care about the actual value in DECL_INITIAL, so we do
5423 not worry that it may be a dangling pointer. */
5424 && DECL_INITIAL (decl) == NULL_TREE
5425 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5426 warning_with_decl (decl,
5427 "`%s' might be used uninitialized in this function");
5429 && TREE_CODE (decl) == VAR_DECL
5430 && DECL_RTL (decl) != 0
5431 && GET_CODE (DECL_RTL (decl)) == REG
5432 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5433 warning_with_decl (decl,
5434 "variable `%s' might be clobbered by `longjmp' or `vfork'");
5436 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5437 uninitialized_vars_warning (sub);
5440 /* Do the appropriate part of uninitialized_vars_warning
5441 but for arguments instead of local variables. */
5444 setjmp_args_warning ()
5447 for (decl = DECL_ARGUMENTS (current_function_decl);
5448 decl; decl = TREE_CHAIN (decl))
5449 if (DECL_RTL (decl) != 0
5450 && GET_CODE (DECL_RTL (decl)) == REG
5451 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5452 warning_with_decl (decl,
5453 "argument `%s' might be clobbered by `longjmp' or `vfork'");
5456 /* If this function call setjmp, put all vars into the stack
5457 unless they were declared `register'. */
5460 setjmp_protect (block)
5464 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5465 if ((TREE_CODE (decl) == VAR_DECL
5466 || TREE_CODE (decl) == PARM_DECL)
5467 && DECL_RTL (decl) != 0
5468 && (GET_CODE (DECL_RTL (decl)) == REG
5469 || (GET_CODE (DECL_RTL (decl)) == MEM
5470 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5471 /* If this variable came from an inline function, it must be
5472 that its life doesn't overlap the setjmp. If there was a
5473 setjmp in the function, it would already be in memory. We
5474 must exclude such variable because their DECL_RTL might be
5475 set to strange things such as virtual_stack_vars_rtx. */
5476 && ! DECL_FROM_INLINE (decl)
5478 #ifdef NON_SAVING_SETJMP
5479 /* If longjmp doesn't restore the registers,
5480 don't put anything in them. */
5484 ! DECL_REGISTER (decl)))
5485 put_var_into_stack (decl);
5486 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5487 setjmp_protect (sub);
5490 /* Like the previous function, but for args instead of local variables. */
5493 setjmp_protect_args ()
5496 for (decl = DECL_ARGUMENTS (current_function_decl);
5497 decl; decl = TREE_CHAIN (decl))
5498 if ((TREE_CODE (decl) == VAR_DECL
5499 || TREE_CODE (decl) == PARM_DECL)
5500 && DECL_RTL (decl) != 0
5501 && (GET_CODE (DECL_RTL (decl)) == REG
5502 || (GET_CODE (DECL_RTL (decl)) == MEM
5503 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5505 /* If longjmp doesn't restore the registers,
5506 don't put anything in them. */
5507 #ifdef NON_SAVING_SETJMP
5511 ! DECL_REGISTER (decl)))
5512 put_var_into_stack (decl);
5515 /* Return the context-pointer register corresponding to DECL,
5516 or 0 if it does not need one. */
5519 lookup_static_chain (decl)
5522 tree context = decl_function_context (decl);
5526 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5529 /* We treat inline_function_decl as an alias for the current function
5530 because that is the inline function whose vars, types, etc.
5531 are being merged into the current function.
5532 See expand_inline_function. */
5533 if (context == current_function_decl || context == inline_function_decl)
5534 return virtual_stack_vars_rtx;
5536 for (link = context_display; link; link = TREE_CHAIN (link))
5537 if (TREE_PURPOSE (link) == context)
5538 return RTL_EXPR_RTL (TREE_VALUE (link));
5543 /* Convert a stack slot address ADDR for variable VAR
5544 (from a containing function)
5545 into an address valid in this function (using a static chain). */
5548 fix_lexical_addr (addr, var)
5553 HOST_WIDE_INT displacement;
5554 tree context = decl_function_context (var);
5555 struct function *fp;
5558 /* If this is the present function, we need not do anything. */
5559 if (context == current_function_decl || context == inline_function_decl)
5562 fp = find_function_data (context);
5564 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5565 addr = XEXP (XEXP (addr, 0), 0);
5567 /* Decode given address as base reg plus displacement. */
5568 if (GET_CODE (addr) == REG)
5569 basereg = addr, displacement = 0;
5570 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5571 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5575 /* We accept vars reached via the containing function's
5576 incoming arg pointer and via its stack variables pointer. */
5577 if (basereg == fp->internal_arg_pointer)
5579 /* If reached via arg pointer, get the arg pointer value
5580 out of that function's stack frame.
5582 There are two cases: If a separate ap is needed, allocate a
5583 slot in the outer function for it and dereference it that way.
5584 This is correct even if the real ap is actually a pseudo.
5585 Otherwise, just adjust the offset from the frame pointer to
5588 #ifdef NEED_SEPARATE_AP
5591 addr = get_arg_pointer_save_area (fp);
5592 addr = fix_lexical_addr (XEXP (addr, 0), var);
5593 addr = memory_address (Pmode, addr);
5595 base = gen_rtx_MEM (Pmode, addr);
5596 set_mem_alias_set (base, get_frame_alias_set ());
5597 base = copy_to_reg (base);
5599 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5600 base = lookup_static_chain (var);
5604 else if (basereg == virtual_stack_vars_rtx)
5606 /* This is the same code as lookup_static_chain, duplicated here to
5607 avoid an extra call to decl_function_context. */
5610 for (link = context_display; link; link = TREE_CHAIN (link))
5611 if (TREE_PURPOSE (link) == context)
5613 base = RTL_EXPR_RTL (TREE_VALUE (link));
5621 /* Use same offset, relative to appropriate static chain or argument
5623 return plus_constant (base, displacement);
5626 /* Return the address of the trampoline for entering nested fn FUNCTION.
5627 If necessary, allocate a trampoline (in the stack frame)
5628 and emit rtl to initialize its contents (at entry to this function). */
5631 trampoline_address (function)
5637 struct function *fp;
5640 /* Find an existing trampoline and return it. */
5641 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5642 if (TREE_PURPOSE (link) == function)
5644 adjust_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5646 for (fp = outer_function_chain; fp; fp = fp->outer)
5647 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5648 if (TREE_PURPOSE (link) == function)
5650 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5652 return adjust_trampoline_addr (tramp);
5655 /* None exists; we must make one. */
5657 /* Find the `struct function' for the function containing FUNCTION. */
5659 fn_context = decl_function_context (function);
5660 if (fn_context != current_function_decl
5661 && fn_context != inline_function_decl)
5662 fp = find_function_data (fn_context);
5664 /* Allocate run-time space for this trampoline
5665 (usually in the defining function's stack frame). */
5666 #ifdef ALLOCATE_TRAMPOLINE
5667 tramp = ALLOCATE_TRAMPOLINE (fp);
5669 /* If rounding needed, allocate extra space
5670 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5671 #define TRAMPOLINE_REAL_SIZE \
5672 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5673 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5677 /* Record the trampoline for reuse and note it for later initialization
5678 by expand_function_end. */
5681 rtlexp = make_node (RTL_EXPR);
5682 RTL_EXPR_RTL (rtlexp) = tramp;
5683 fp->x_trampoline_list = tree_cons (function, rtlexp,
5684 fp->x_trampoline_list);
5688 /* Make the RTL_EXPR node temporary, not momentary, so that the
5689 trampoline_list doesn't become garbage. */
5690 rtlexp = make_node (RTL_EXPR);
5692 RTL_EXPR_RTL (rtlexp) = tramp;
5693 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5696 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5697 return adjust_trampoline_addr (tramp);
5700 /* Given a trampoline address,
5701 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5704 round_trampoline_addr (tramp)
5707 /* Round address up to desired boundary. */
5708 rtx temp = gen_reg_rtx (Pmode);
5709 rtx addend = GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1);
5710 rtx mask = GEN_INT (-TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
5712 temp = expand_simple_binop (Pmode, PLUS, tramp, addend,
5713 temp, 0, OPTAB_LIB_WIDEN);
5714 tramp = expand_simple_binop (Pmode, AND, temp, mask,
5715 temp, 0, OPTAB_LIB_WIDEN);
5720 /* Given a trampoline address, round it then apply any
5721 platform-specific adjustments so that the result can be used for a
5725 adjust_trampoline_addr (tramp)
5728 tramp = round_trampoline_addr (tramp);
5729 #ifdef TRAMPOLINE_ADJUST_ADDRESS
5730 TRAMPOLINE_ADJUST_ADDRESS (tramp);
5735 /* Put all this function's BLOCK nodes including those that are chained
5736 onto the first block into a vector, and return it.
5737 Also store in each NOTE for the beginning or end of a block
5738 the index of that block in the vector.
5739 The arguments are BLOCK, the chain of top-level blocks of the function,
5740 and INSNS, the insn chain of the function. */
5746 tree *block_vector, *last_block_vector;
5748 tree block = DECL_INITIAL (current_function_decl);
5753 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5754 depth-first order. */
5755 block_vector = get_block_vector (block, &n_blocks);
5756 block_stack = (tree *) xmalloc (n_blocks * sizeof (tree));
5758 last_block_vector = identify_blocks_1 (get_insns (),
5760 block_vector + n_blocks,
5763 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5764 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5765 if (0 && last_block_vector != block_vector + n_blocks)
5768 free (block_vector);
5772 /* Subroutine of identify_blocks. Do the block substitution on the
5773 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
5775 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5776 BLOCK_VECTOR is incremented for each block seen. */
5779 identify_blocks_1 (insns, block_vector, end_block_vector, orig_block_stack)
5782 tree *end_block_vector;
5783 tree *orig_block_stack;
5786 tree *block_stack = orig_block_stack;
5788 for (insn = insns; insn; insn = NEXT_INSN (insn))
5790 if (GET_CODE (insn) == NOTE)
5792 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5796 /* If there are more block notes than BLOCKs, something
5798 if (block_vector == end_block_vector)
5801 b = *block_vector++;
5802 NOTE_BLOCK (insn) = b;
5805 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5807 /* If there are more NOTE_INSN_BLOCK_ENDs than
5808 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
5809 if (block_stack == orig_block_stack)
5812 NOTE_BLOCK (insn) = *--block_stack;
5815 else if (GET_CODE (insn) == CALL_INSN
5816 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5818 rtx cp = PATTERN (insn);
5820 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
5821 end_block_vector, block_stack);
5823 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
5824 end_block_vector, block_stack);
5826 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
5827 end_block_vector, block_stack);
5831 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
5832 something is badly wrong. */
5833 if (block_stack != orig_block_stack)
5836 return block_vector;
5839 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
5840 and create duplicate blocks. */
5841 /* ??? Need an option to either create block fragments or to create
5842 abstract origin duplicates of a source block. It really depends
5843 on what optimization has been performed. */
5848 tree block = DECL_INITIAL (current_function_decl);
5849 varray_type block_stack;
5851 if (block == NULL_TREE)
5854 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
5856 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
5857 reorder_blocks_0 (block);
5859 /* Prune the old trees away, so that they don't get in the way. */
5860 BLOCK_SUBBLOCKS (block) = NULL_TREE;
5861 BLOCK_CHAIN (block) = NULL_TREE;
5863 /* Recreate the block tree from the note nesting. */
5864 reorder_blocks_1 (get_insns (), block, &block_stack);
5865 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
5867 /* Remove deleted blocks from the block fragment chains. */
5868 reorder_fix_fragments (block);
5871 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
5874 reorder_blocks_0 (block)
5879 TREE_ASM_WRITTEN (block) = 0;
5880 reorder_blocks_0 (BLOCK_SUBBLOCKS (block));
5881 block = BLOCK_CHAIN (block);
5886 reorder_blocks_1 (insns, current_block, p_block_stack)
5889 varray_type *p_block_stack;
5893 for (insn = insns; insn; insn = NEXT_INSN (insn))
5895 if (GET_CODE (insn) == NOTE)
5897 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5899 tree block = NOTE_BLOCK (insn);
5901 /* If we have seen this block before, that means it now
5902 spans multiple address regions. Create a new fragment. */
5903 if (TREE_ASM_WRITTEN (block))
5905 tree new_block = copy_node (block);
5908 origin = (BLOCK_FRAGMENT_ORIGIN (block)
5909 ? BLOCK_FRAGMENT_ORIGIN (block)
5911 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
5912 BLOCK_FRAGMENT_CHAIN (new_block)
5913 = BLOCK_FRAGMENT_CHAIN (origin);
5914 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
5916 NOTE_BLOCK (insn) = new_block;
5920 BLOCK_SUBBLOCKS (block) = 0;
5921 TREE_ASM_WRITTEN (block) = 1;
5922 BLOCK_SUPERCONTEXT (block) = current_block;
5923 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
5924 BLOCK_SUBBLOCKS (current_block) = block;
5925 current_block = block;
5926 VARRAY_PUSH_TREE (*p_block_stack, block);
5928 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5930 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
5931 VARRAY_POP (*p_block_stack);
5932 BLOCK_SUBBLOCKS (current_block)
5933 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5934 current_block = BLOCK_SUPERCONTEXT (current_block);
5937 else if (GET_CODE (insn) == CALL_INSN
5938 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5940 rtx cp = PATTERN (insn);
5941 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
5943 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
5945 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
5950 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
5951 appears in the block tree, select one of the fragments to become
5952 the new origin block. */
5955 reorder_fix_fragments (block)
5960 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
5961 tree new_origin = NULL_TREE;
5965 if (! TREE_ASM_WRITTEN (dup_origin))
5967 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
5969 /* Find the first of the remaining fragments. There must
5970 be at least one -- the current block. */
5971 while (! TREE_ASM_WRITTEN (new_origin))
5972 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
5973 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
5976 else if (! dup_origin)
5979 /* Re-root the rest of the fragments to the new origin. In the
5980 case that DUP_ORIGIN was null, that means BLOCK was the origin
5981 of a chain of fragments and we want to remove those fragments
5982 that didn't make it to the output. */
5985 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
5990 if (TREE_ASM_WRITTEN (chain))
5992 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
5994 pp = &BLOCK_FRAGMENT_CHAIN (chain);
5996 chain = BLOCK_FRAGMENT_CHAIN (chain);
6001 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
6002 block = BLOCK_CHAIN (block);
6006 /* Reverse the order of elements in the chain T of blocks,
6007 and return the new head of the chain (old last element). */
6013 tree prev = 0, decl, next;
6014 for (decl = t; decl; decl = next)
6016 next = BLOCK_CHAIN (decl);
6017 BLOCK_CHAIN (decl) = prev;
6023 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
6024 non-NULL, list them all into VECTOR, in a depth-first preorder
6025 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
6029 all_blocks (block, vector)
6037 TREE_ASM_WRITTEN (block) = 0;
6039 /* Record this block. */
6041 vector[n_blocks] = block;
6045 /* Record the subblocks, and their subblocks... */
6046 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
6047 vector ? vector + n_blocks : 0);
6048 block = BLOCK_CHAIN (block);
6054 /* Return a vector containing all the blocks rooted at BLOCK. The
6055 number of elements in the vector is stored in N_BLOCKS_P. The
6056 vector is dynamically allocated; it is the caller's responsibility
6057 to call `free' on the pointer returned. */
6060 get_block_vector (block, n_blocks_p)
6066 *n_blocks_p = all_blocks (block, NULL);
6067 block_vector = (tree *) xmalloc (*n_blocks_p * sizeof (tree));
6068 all_blocks (block, block_vector);
6070 return block_vector;
6073 static int next_block_index = 2;
6075 /* Set BLOCK_NUMBER for all the blocks in FN. */
6085 /* For SDB and XCOFF debugging output, we start numbering the blocks
6086 from 1 within each function, rather than keeping a running
6088 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6089 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
6090 next_block_index = 1;
6093 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
6095 /* The top-level BLOCK isn't numbered at all. */
6096 for (i = 1; i < n_blocks; ++i)
6097 /* We number the blocks from two. */
6098 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
6100 free (block_vector);
6105 /* If VAR is present in a subblock of BLOCK, return the subblock. */
6108 debug_find_var_in_block_tree (var, block)
6114 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
6118 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
6120 tree ret = debug_find_var_in_block_tree (var, t);
6128 /* Allocate a function structure and reset its contents to the defaults. */
6131 prepare_function_start ()
6133 cfun = (struct function *) ggc_alloc_cleared (sizeof (struct function));
6135 init_stmt_for_function ();
6136 init_eh_for_function ();
6138 cse_not_expected = ! optimize;
6140 /* Caller save not needed yet. */
6141 caller_save_needed = 0;
6143 /* No stack slots have been made yet. */
6144 stack_slot_list = 0;
6146 current_function_has_nonlocal_label = 0;
6147 current_function_has_nonlocal_goto = 0;
6149 /* There is no stack slot for handling nonlocal gotos. */
6150 nonlocal_goto_handler_slots = 0;
6151 nonlocal_goto_stack_level = 0;
6153 /* No labels have been declared for nonlocal use. */
6154 nonlocal_labels = 0;
6155 nonlocal_goto_handler_labels = 0;
6157 /* No function calls so far in this function. */
6158 function_call_count = 0;
6160 /* No parm regs have been allocated.
6161 (This is important for output_inline_function.) */
6162 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
6164 /* Initialize the RTL mechanism. */
6167 /* Initialize the queue of pending postincrement and postdecrements,
6168 and some other info in expr.c. */
6171 /* We haven't done register allocation yet. */
6174 init_varasm_status (cfun);
6176 /* Clear out data used for inlining. */
6177 cfun->inlinable = 0;
6178 cfun->original_decl_initial = 0;
6179 cfun->original_arg_vector = 0;
6181 cfun->stack_alignment_needed = STACK_BOUNDARY;
6182 cfun->preferred_stack_boundary = STACK_BOUNDARY;
6184 /* Set if a call to setjmp is seen. */
6185 current_function_calls_setjmp = 0;
6187 /* Set if a call to longjmp is seen. */
6188 current_function_calls_longjmp = 0;
6190 current_function_calls_alloca = 0;
6191 current_function_calls_eh_return = 0;
6192 current_function_calls_constant_p = 0;
6193 current_function_contains_functions = 0;
6194 current_function_is_leaf = 0;
6195 current_function_nothrow = 0;
6196 current_function_sp_is_unchanging = 0;
6197 current_function_uses_only_leaf_regs = 0;
6198 current_function_has_computed_jump = 0;
6199 current_function_is_thunk = 0;
6201 current_function_returns_pcc_struct = 0;
6202 current_function_returns_struct = 0;
6203 current_function_epilogue_delay_list = 0;
6204 current_function_uses_const_pool = 0;
6205 current_function_uses_pic_offset_table = 0;
6206 current_function_cannot_inline = 0;
6208 /* We have not yet needed to make a label to jump to for tail-recursion. */
6209 tail_recursion_label = 0;
6211 /* We haven't had a need to make a save area for ap yet. */
6212 arg_pointer_save_area = 0;
6214 /* No stack slots allocated yet. */
6217 /* No SAVE_EXPRs in this function yet. */
6220 /* No RTL_EXPRs in this function yet. */
6223 /* Set up to allocate temporaries. */
6226 /* Indicate that we need to distinguish between the return value of the
6227 present function and the return value of a function being called. */
6228 rtx_equal_function_value_matters = 1;
6230 /* Indicate that we have not instantiated virtual registers yet. */
6231 virtuals_instantiated = 0;
6233 /* Indicate that we want CONCATs now. */
6234 generating_concat_p = 1;
6236 /* Indicate we have no need of a frame pointer yet. */
6237 frame_pointer_needed = 0;
6239 /* By default assume not stdarg. */
6240 current_function_stdarg = 0;
6242 /* We haven't made any trampolines for this function yet. */
6243 trampoline_list = 0;
6245 init_pending_stack_adjust ();
6246 inhibit_defer_pop = 0;
6248 current_function_outgoing_args_size = 0;
6250 current_function_funcdef_no = funcdef_no++;
6252 cfun->arc_profile = profile_arc_flag || flag_test_coverage;
6254 cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL;
6256 cfun->max_jumptable_ents = 0;
6258 (*lang_hooks.function.init) (cfun);
6259 if (init_machine_status)
6260 cfun->machine = (*init_machine_status) ();
6263 /* Initialize the rtl expansion mechanism so that we can do simple things
6264 like generate sequences. This is used to provide a context during global
6265 initialization of some passes. */
6267 init_dummy_function_start ()
6269 prepare_function_start ();
6272 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6273 and initialize static variables for generating RTL for the statements
6277 init_function_start (subr, filename, line)
6279 const char *filename;
6282 prepare_function_start ();
6284 current_function_name = (*lang_hooks.decl_printable_name) (subr, 2);
6287 /* Nonzero if this is a nested function that uses a static chain. */
6289 current_function_needs_context
6290 = (decl_function_context (current_function_decl) != 0
6291 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
6293 /* Within function body, compute a type's size as soon it is laid out. */
6294 immediate_size_expand++;
6296 /* Prevent ever trying to delete the first instruction of a function.
6297 Also tell final how to output a linenum before the function prologue.
6298 Note linenums could be missing, e.g. when compiling a Java .class file. */
6300 emit_line_note (filename, line);
6302 /* Make sure first insn is a note even if we don't want linenums.
6303 This makes sure the first insn will never be deleted.
6304 Also, final expects a note to appear there. */
6305 emit_note (NULL, NOTE_INSN_DELETED);
6307 /* Set flags used by final.c. */
6308 if (aggregate_value_p (DECL_RESULT (subr)))
6310 #ifdef PCC_STATIC_STRUCT_RETURN
6311 current_function_returns_pcc_struct = 1;
6313 current_function_returns_struct = 1;
6316 /* Warn if this value is an aggregate type,
6317 regardless of which calling convention we are using for it. */
6318 if (warn_aggregate_return
6319 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6320 warning ("function returns an aggregate");
6322 current_function_returns_pointer
6323 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
6326 /* Make sure all values used by the optimization passes have sane
6329 init_function_for_compilation ()
6333 /* No prologue/epilogue insns yet. */
6334 VARRAY_GROW (prologue, 0);
6335 VARRAY_GROW (epilogue, 0);
6336 VARRAY_GROW (sibcall_epilogue, 0);
6339 /* Expand a call to __main at the beginning of a possible main function. */
6341 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6342 #undef HAS_INIT_SECTION
6343 #define HAS_INIT_SECTION
6347 expand_main_function ()
6349 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
6350 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
6352 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
6356 /* Forcibly align the stack. */
6357 #ifdef STACK_GROWS_DOWNWARD
6358 tmp = expand_simple_binop (Pmode, AND, stack_pointer_rtx, GEN_INT(-align),
6359 stack_pointer_rtx, 1, OPTAB_WIDEN);
6361 tmp = expand_simple_binop (Pmode, PLUS, stack_pointer_rtx,
6362 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
6363 tmp = expand_simple_binop (Pmode, AND, tmp, GEN_INT (-align),
6364 stack_pointer_rtx, 1, OPTAB_WIDEN);
6366 if (tmp != stack_pointer_rtx)
6367 emit_move_insn (stack_pointer_rtx, tmp);
6369 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
6370 tmp = force_reg (Pmode, const0_rtx);
6371 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
6375 for (tmp = get_last_insn (); tmp; tmp = PREV_INSN (tmp))
6376 if (NOTE_P (tmp) && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_FUNCTION_BEG)
6379 emit_insn_before (seq, tmp);
6385 #ifndef HAS_INIT_SECTION
6386 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, NAME__MAIN), LCT_NORMAL,
6391 /* The PENDING_SIZES represent the sizes of variable-sized types.
6392 Create RTL for the various sizes now (using temporary variables),
6393 so that we can refer to the sizes from the RTL we are generating
6394 for the current function. The PENDING_SIZES are a TREE_LIST. The
6395 TREE_VALUE of each node is a SAVE_EXPR. */
6398 expand_pending_sizes (pending_sizes)
6403 /* Evaluate now the sizes of any types declared among the arguments. */
6404 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
6406 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode, 0);
6407 /* Flush the queue in case this parameter declaration has
6413 /* Start the RTL for a new function, and set variables used for
6415 SUBR is the FUNCTION_DECL node.
6416 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6417 the function's parameters, which must be run at any return statement. */
6420 expand_function_start (subr, parms_have_cleanups)
6422 int parms_have_cleanups;
6425 rtx last_ptr = NULL_RTX;
6427 /* Make sure volatile mem refs aren't considered
6428 valid operands of arithmetic insns. */
6429 init_recog_no_volatile ();
6431 current_function_instrument_entry_exit
6432 = (flag_instrument_function_entry_exit
6433 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6435 current_function_profile
6437 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6439 current_function_limit_stack
6440 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6442 /* If function gets a static chain arg, store it in the stack frame.
6443 Do this first, so it gets the first stack slot offset. */
6444 if (current_function_needs_context)
6446 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
6448 /* Delay copying static chain if it is not a register to avoid
6449 conflicts with regs used for parameters. */
6450 if (! SMALL_REGISTER_CLASSES
6451 || GET_CODE (static_chain_incoming_rtx) == REG)
6452 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6455 /* If the parameters of this function need cleaning up, get a label
6456 for the beginning of the code which executes those cleanups. This must
6457 be done before doing anything with return_label. */
6458 if (parms_have_cleanups)
6459 cleanup_label = gen_label_rtx ();
6463 /* Make the label for return statements to jump to. Do not special
6464 case machines with special return instructions -- they will be
6465 handled later during jump, ifcvt, or epilogue creation. */
6466 return_label = gen_label_rtx ();
6468 /* Initialize rtx used to return the value. */
6469 /* Do this before assign_parms so that we copy the struct value address
6470 before any library calls that assign parms might generate. */
6472 /* Decide whether to return the value in memory or in a register. */
6473 if (aggregate_value_p (DECL_RESULT (subr)))
6475 /* Returning something that won't go in a register. */
6476 rtx value_address = 0;
6478 #ifdef PCC_STATIC_STRUCT_RETURN
6479 if (current_function_returns_pcc_struct)
6481 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6482 value_address = assemble_static_space (size);
6487 /* Expect to be passed the address of a place to store the value.
6488 If it is passed as an argument, assign_parms will take care of
6490 if (struct_value_incoming_rtx)
6492 value_address = gen_reg_rtx (Pmode);
6493 emit_move_insn (value_address, struct_value_incoming_rtx);
6498 rtx x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
6499 set_mem_attributes (x, DECL_RESULT (subr), 1);
6500 SET_DECL_RTL (DECL_RESULT (subr), x);
6503 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6504 /* If return mode is void, this decl rtl should not be used. */
6505 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
6508 /* Compute the return values into a pseudo reg, which we will copy
6509 into the true return register after the cleanups are done. */
6511 /* In order to figure out what mode to use for the pseudo, we
6512 figure out what the mode of the eventual return register will
6513 actually be, and use that. */
6515 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
6518 /* Structures that are returned in registers are not aggregate_value_p,
6519 so we may see a PARALLEL or a REG. */
6520 if (REG_P (hard_reg))
6521 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg)));
6522 else if (GET_CODE (hard_reg) == PARALLEL)
6523 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
6527 /* Set DECL_REGISTER flag so that expand_function_end will copy the
6528 result to the real return register(s). */
6529 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6532 /* Initialize rtx for parameters and local variables.
6533 In some cases this requires emitting insns. */
6535 assign_parms (subr);
6537 /* Copy the static chain now if it wasn't a register. The delay is to
6538 avoid conflicts with the parameter passing registers. */
6540 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6541 if (GET_CODE (static_chain_incoming_rtx) != REG)
6542 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6544 /* The following was moved from init_function_start.
6545 The move is supposed to make sdb output more accurate. */
6546 /* Indicate the beginning of the function body,
6547 as opposed to parm setup. */
6548 emit_note (NULL, NOTE_INSN_FUNCTION_BEG);
6550 if (GET_CODE (get_last_insn ()) != NOTE)
6551 emit_note (NULL, NOTE_INSN_DELETED);
6552 parm_birth_insn = get_last_insn ();
6554 context_display = 0;
6555 if (current_function_needs_context)
6557 /* Fetch static chain values for containing functions. */
6558 tem = decl_function_context (current_function_decl);
6559 /* Copy the static chain pointer into a pseudo. If we have
6560 small register classes, copy the value from memory if
6561 static_chain_incoming_rtx is a REG. */
6564 /* If the static chain originally came in a register, put it back
6565 there, then move it out in the next insn. The reason for
6566 this peculiar code is to satisfy function integration. */
6567 if (SMALL_REGISTER_CLASSES
6568 && GET_CODE (static_chain_incoming_rtx) == REG)
6569 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6570 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6575 tree rtlexp = make_node (RTL_EXPR);
6577 RTL_EXPR_RTL (rtlexp) = last_ptr;
6578 context_display = tree_cons (tem, rtlexp, context_display);
6579 tem = decl_function_context (tem);
6582 /* Chain thru stack frames, assuming pointer to next lexical frame
6583 is found at the place we always store it. */
6584 #ifdef FRAME_GROWS_DOWNWARD
6585 last_ptr = plus_constant (last_ptr,
6586 -(HOST_WIDE_INT) GET_MODE_SIZE (Pmode));
6588 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr));
6589 set_mem_alias_set (last_ptr, get_frame_alias_set ());
6590 last_ptr = copy_to_reg (last_ptr);
6592 /* If we are not optimizing, ensure that we know that this
6593 piece of context is live over the entire function. */
6595 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6600 if (current_function_instrument_entry_exit)
6602 rtx fun = DECL_RTL (current_function_decl);
6603 if (GET_CODE (fun) == MEM)
6604 fun = XEXP (fun, 0);
6607 emit_library_call (profile_function_entry_libfunc, LCT_NORMAL, VOIDmode,
6609 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6611 hard_frame_pointer_rtx),
6615 if (current_function_profile)
6618 PROFILE_HOOK (current_function_funcdef_no);
6622 /* After the display initializations is where the tail-recursion label
6623 should go, if we end up needing one. Ensure we have a NOTE here
6624 since some things (like trampolines) get placed before this. */
6625 tail_recursion_reentry = emit_note (NULL, NOTE_INSN_DELETED);
6627 /* Evaluate now the sizes of any types declared among the arguments. */
6628 expand_pending_sizes (nreverse (get_pending_sizes ()));
6630 /* Make sure there is a line number after the function entry setup code. */
6631 force_next_line_note ();
6634 /* Undo the effects of init_dummy_function_start. */
6636 expand_dummy_function_end ()
6638 /* End any sequences that failed to be closed due to syntax errors. */
6639 while (in_sequence_p ())
6642 /* Outside function body, can't compute type's actual size
6643 until next function's body starts. */
6645 free_after_parsing (cfun);
6646 free_after_compilation (cfun);
6650 /* Call DOIT for each hard register used as a return value from
6651 the current function. */
6654 diddle_return_value (doit, arg)
6655 void (*doit) PARAMS ((rtx, void *));
6658 rtx outgoing = current_function_return_rtx;
6663 if (GET_CODE (outgoing) == REG)
6664 (*doit) (outgoing, arg);
6665 else if (GET_CODE (outgoing) == PARALLEL)
6669 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6671 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6673 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6680 do_clobber_return_reg (reg, arg)
6682 void *arg ATTRIBUTE_UNUSED;
6684 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6688 clobber_return_register ()
6690 diddle_return_value (do_clobber_return_reg, NULL);
6692 /* In case we do use pseudo to return value, clobber it too. */
6693 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6695 tree decl_result = DECL_RESULT (current_function_decl);
6696 rtx decl_rtl = DECL_RTL (decl_result);
6697 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
6699 do_clobber_return_reg (decl_rtl, NULL);
6705 do_use_return_reg (reg, arg)
6707 void *arg ATTRIBUTE_UNUSED;
6709 emit_insn (gen_rtx_USE (VOIDmode, reg));
6713 use_return_register ()
6715 diddle_return_value (do_use_return_reg, NULL);
6718 static GTY(()) rtx initial_trampoline;
6720 /* Generate RTL for the end of the current function.
6721 FILENAME and LINE are the current position in the source file.
6723 It is up to language-specific callers to do cleanups for parameters--
6724 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
6727 expand_function_end (filename, line, end_bindings)
6728 const char *filename;
6735 finish_expr_for_function ();
6737 /* If arg_pointer_save_area was referenced only from a nested
6738 function, we will not have initialized it yet. Do that now. */
6739 if (arg_pointer_save_area && ! cfun->arg_pointer_save_area_init)
6740 get_arg_pointer_save_area (cfun);
6742 #ifdef NON_SAVING_SETJMP
6743 /* Don't put any variables in registers if we call setjmp
6744 on a machine that fails to restore the registers. */
6745 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6747 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6748 setjmp_protect (DECL_INITIAL (current_function_decl));
6750 setjmp_protect_args ();
6754 /* Initialize any trampolines required by this function. */
6755 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6757 tree function = TREE_PURPOSE (link);
6758 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6759 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6760 #ifdef TRAMPOLINE_TEMPLATE
6765 #ifdef TRAMPOLINE_TEMPLATE
6766 /* First make sure this compilation has a template for
6767 initializing trampolines. */
6768 if (initial_trampoline == 0)
6771 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6772 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
6776 /* Generate insns to initialize the trampoline. */
6778 tramp = round_trampoline_addr (XEXP (tramp, 0));
6779 #ifdef TRAMPOLINE_TEMPLATE
6780 blktramp = replace_equiv_address (initial_trampoline, tramp);
6781 emit_block_move (blktramp, initial_trampoline,
6782 GEN_INT (TRAMPOLINE_SIZE), BLOCK_OP_NORMAL);
6784 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6788 /* Put those insns at entry to the containing function (this one). */
6789 emit_insn_before (seq, tail_recursion_reentry);
6792 /* If we are doing stack checking and this function makes calls,
6793 do a stack probe at the start of the function to ensure we have enough
6794 space for another stack frame. */
6795 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6799 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6800 if (GET_CODE (insn) == CALL_INSN)
6803 probe_stack_range (STACK_CHECK_PROTECT,
6804 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6807 emit_insn_before (seq, tail_recursion_reentry);
6812 /* Warn about unused parms if extra warnings were specified. */
6813 /* Either ``-Wextra -Wunused'' or ``-Wunused-parameter'' enables this
6814 warning. WARN_UNUSED_PARAMETER is negative when set by
6815 -Wunused. Note that -Wall implies -Wunused, so ``-Wall -Wextra'' will
6816 also give these warnings. */
6817 if (warn_unused_parameter > 0
6818 || (warn_unused_parameter < 0 && extra_warnings))
6822 for (decl = DECL_ARGUMENTS (current_function_decl);
6823 decl; decl = TREE_CHAIN (decl))
6824 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6825 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6826 warning_with_decl (decl, "unused parameter `%s'");
6829 /* Delete handlers for nonlocal gotos if nothing uses them. */
6830 if (nonlocal_goto_handler_slots != 0
6831 && ! current_function_has_nonlocal_label)
6834 /* End any sequences that failed to be closed due to syntax errors. */
6835 while (in_sequence_p ())
6838 /* Outside function body, can't compute type's actual size
6839 until next function's body starts. */
6840 immediate_size_expand--;
6842 clear_pending_stack_adjust ();
6843 do_pending_stack_adjust ();
6845 /* Mark the end of the function body.
6846 If control reaches this insn, the function can drop through
6847 without returning a value. */
6848 emit_note (NULL, NOTE_INSN_FUNCTION_END);
6850 /* Must mark the last line number note in the function, so that the test
6851 coverage code can avoid counting the last line twice. This just tells
6852 the code to ignore the immediately following line note, since there
6853 already exists a copy of this note somewhere above. This line number
6854 note is still needed for debugging though, so we can't delete it. */
6855 if (flag_test_coverage)
6856 emit_note (NULL, NOTE_INSN_REPEATED_LINE_NUMBER);
6858 /* Output a linenumber for the end of the function.
6859 SDB depends on this. */
6860 emit_line_note_force (filename, line);
6862 /* Before the return label (if any), clobber the return
6863 registers so that they are not propagated live to the rest of
6864 the function. This can only happen with functions that drop
6865 through; if there had been a return statement, there would
6866 have either been a return rtx, or a jump to the return label.
6868 We delay actual code generation after the current_function_value_rtx
6870 clobber_after = get_last_insn ();
6872 /* Output the label for the actual return from the function,
6873 if one is expected. This happens either because a function epilogue
6874 is used instead of a return instruction, or because a return was done
6875 with a goto in order to run local cleanups, or because of pcc-style
6876 structure returning. */
6878 emit_label (return_label);
6880 /* C++ uses this. */
6882 expand_end_bindings (0, 0, 0);
6884 if (current_function_instrument_entry_exit)
6886 rtx fun = DECL_RTL (current_function_decl);
6887 if (GET_CODE (fun) == MEM)
6888 fun = XEXP (fun, 0);
6891 emit_library_call (profile_function_exit_libfunc, LCT_NORMAL, VOIDmode,
6893 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6895 hard_frame_pointer_rtx),
6899 /* Let except.c know where it should emit the call to unregister
6900 the function context for sjlj exceptions. */
6901 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
6902 sjlj_emit_function_exit_after (get_last_insn ());
6904 /* If we had calls to alloca, and this machine needs
6905 an accurate stack pointer to exit the function,
6906 insert some code to save and restore the stack pointer. */
6907 #ifdef EXIT_IGNORE_STACK
6908 if (! EXIT_IGNORE_STACK)
6910 if (current_function_calls_alloca)
6914 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
6915 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
6918 /* If scalar return value was computed in a pseudo-reg, or was a named
6919 return value that got dumped to the stack, copy that to the hard
6921 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6923 tree decl_result = DECL_RESULT (current_function_decl);
6924 rtx decl_rtl = DECL_RTL (decl_result);
6926 if (REG_P (decl_rtl)
6927 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
6928 : DECL_REGISTER (decl_result))
6930 rtx real_decl_rtl = current_function_return_rtx;
6932 /* This should be set in assign_parms. */
6933 if (! REG_FUNCTION_VALUE_P (real_decl_rtl))
6936 /* If this is a BLKmode structure being returned in registers,
6937 then use the mode computed in expand_return. Note that if
6938 decl_rtl is memory, then its mode may have been changed,
6939 but that current_function_return_rtx has not. */
6940 if (GET_MODE (real_decl_rtl) == BLKmode)
6941 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
6943 /* If a named return value dumped decl_return to memory, then
6944 we may need to re-do the PROMOTE_MODE signed/unsigned
6946 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
6948 int unsignedp = TREE_UNSIGNED (TREE_TYPE (decl_result));
6950 #ifdef PROMOTE_FUNCTION_RETURN
6951 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
6955 convert_move (real_decl_rtl, decl_rtl, unsignedp);
6957 else if (GET_CODE (real_decl_rtl) == PARALLEL)
6959 /* If expand_function_start has created a PARALLEL for decl_rtl,
6960 move the result to the real return registers. Otherwise, do
6961 a group load from decl_rtl for a named return. */
6962 if (GET_CODE (decl_rtl) == PARALLEL)
6963 emit_group_move (real_decl_rtl, decl_rtl);
6965 emit_group_load (real_decl_rtl, decl_rtl,
6966 int_size_in_bytes (TREE_TYPE (decl_result)));
6969 emit_move_insn (real_decl_rtl, decl_rtl);
6973 /* If returning a structure, arrange to return the address of the value
6974 in a place where debuggers expect to find it.
6976 If returning a structure PCC style,
6977 the caller also depends on this value.
6978 And current_function_returns_pcc_struct is not necessarily set. */
6979 if (current_function_returns_struct
6980 || current_function_returns_pcc_struct)
6983 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
6984 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
6985 #ifdef FUNCTION_OUTGOING_VALUE
6987 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
6988 current_function_decl);
6991 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
6994 /* Mark this as a function return value so integrate will delete the
6995 assignment and USE below when inlining this function. */
6996 REG_FUNCTION_VALUE_P (outgoing) = 1;
6998 #ifdef POINTERS_EXTEND_UNSIGNED
6999 /* The address may be ptr_mode and OUTGOING may be Pmode. */
7000 if (GET_MODE (outgoing) != GET_MODE (value_address))
7001 value_address = convert_memory_address (GET_MODE (outgoing),
7005 emit_move_insn (outgoing, value_address);
7007 /* Show return register used to hold result (in this case the address
7009 current_function_return_rtx = outgoing;
7012 /* If this is an implementation of throw, do what's necessary to
7013 communicate between __builtin_eh_return and the epilogue. */
7014 expand_eh_return ();
7016 /* Emit the actual code to clobber return register. */
7021 clobber_return_register ();
7025 after = emit_insn_after (seq, clobber_after);
7027 if (clobber_after != after)
7028 cfun->x_clobber_return_insn = after;
7031 /* ??? This should no longer be necessary since stupid is no longer with
7032 us, but there are some parts of the compiler (eg reload_combine, and
7033 sh mach_dep_reorg) that still try and compute their own lifetime info
7034 instead of using the general framework. */
7035 use_return_register ();
7037 /* Fix up any gotos that jumped out to the outermost
7038 binding level of the function.
7039 Must follow emitting RETURN_LABEL. */
7041 /* If you have any cleanups to do at this point,
7042 and they need to create temporary variables,
7043 then you will lose. */
7044 expand_fixups (get_insns ());
7048 get_arg_pointer_save_area (f)
7051 rtx ret = f->x_arg_pointer_save_area;
7055 ret = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, f);
7056 f->x_arg_pointer_save_area = ret;
7059 if (f == cfun && ! f->arg_pointer_save_area_init)
7063 /* Save the arg pointer at the beginning of the function. The
7064 generated stack slot may not be a valid memory address, so we
7065 have to check it and fix it if necessary. */
7067 emit_move_insn (validize_mem (ret), virtual_incoming_args_rtx);
7071 push_topmost_sequence ();
7072 emit_insn_after (seq, get_insns ());
7073 pop_topmost_sequence ();
7079 /* Extend a vector that records the INSN_UIDs of INSNS
7080 (a list of one or more insns). */
7083 record_insns (insns, vecp)
7092 while (tmp != NULL_RTX)
7095 tmp = NEXT_INSN (tmp);
7098 i = VARRAY_SIZE (*vecp);
7099 VARRAY_GROW (*vecp, i + len);
7101 while (tmp != NULL_RTX)
7103 VARRAY_INT (*vecp, i) = INSN_UID (tmp);
7105 tmp = NEXT_INSN (tmp);
7109 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
7110 be running after reorg, SEQUENCE rtl is possible. */
7113 contains (insn, vec)
7119 if (GET_CODE (insn) == INSN
7120 && GET_CODE (PATTERN (insn)) == SEQUENCE)
7123 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
7124 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7125 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
7131 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7132 if (INSN_UID (insn) == VARRAY_INT (vec, j))
7139 prologue_epilogue_contains (insn)
7142 if (contains (insn, prologue))
7144 if (contains (insn, epilogue))
7150 sibcall_epilogue_contains (insn)
7153 if (sibcall_epilogue)
7154 return contains (insn, sibcall_epilogue);
7159 /* Insert gen_return at the end of block BB. This also means updating
7160 block_for_insn appropriately. */
7163 emit_return_into_block (bb, line_note)
7167 emit_jump_insn_after (gen_return (), bb->end);
7169 emit_line_note_after (NOTE_SOURCE_FILE (line_note),
7170 NOTE_LINE_NUMBER (line_note), PREV_INSN (bb->end));
7172 #endif /* HAVE_return */
7174 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
7176 /* These functions convert the epilogue into a variant that does not modify the
7177 stack pointer. This is used in cases where a function returns an object
7178 whose size is not known until it is computed. The called function leaves the
7179 object on the stack, leaves the stack depressed, and returns a pointer to
7182 What we need to do is track all modifications and references to the stack
7183 pointer, deleting the modifications and changing the references to point to
7184 the location the stack pointer would have pointed to had the modifications
7187 These functions need to be portable so we need to make as few assumptions
7188 about the epilogue as we can. However, the epilogue basically contains
7189 three things: instructions to reset the stack pointer, instructions to
7190 reload registers, possibly including the frame pointer, and an
7191 instruction to return to the caller.
7193 If we can't be sure of what a relevant epilogue insn is doing, we abort.
7194 We also make no attempt to validate the insns we make since if they are
7195 invalid, we probably can't do anything valid. The intent is that these
7196 routines get "smarter" as more and more machines start to use them and
7197 they try operating on different epilogues.
7199 We use the following structure to track what the part of the epilogue that
7200 we've already processed has done. We keep two copies of the SP equivalence,
7201 one for use during the insn we are processing and one for use in the next
7202 insn. The difference is because one part of a PARALLEL may adjust SP
7203 and the other may use it. */
7207 rtx sp_equiv_reg; /* REG that SP is set from, perhaps SP. */
7208 HOST_WIDE_INT sp_offset; /* Offset from SP_EQUIV_REG of present SP. */
7209 rtx new_sp_equiv_reg; /* REG to be used at end of insn. */
7210 HOST_WIDE_INT new_sp_offset; /* Offset to be used at end of insn. */
7211 rtx equiv_reg_src; /* If nonzero, the value that SP_EQUIV_REG
7212 should be set to once we no longer need
7216 static void handle_epilogue_set PARAMS ((rtx, struct epi_info *));
7217 static void emit_equiv_load PARAMS ((struct epi_info *));
7219 /* Modify INSN, a list of one or more insns that is part of the epilogue, to
7220 no modifications to the stack pointer. Return the new list of insns. */
7223 keep_stack_depressed (insns)
7227 struct epi_info info;
7230 /* If the epilogue is just a single instruction, it ust be OK as is. */
7232 if (NEXT_INSN (insns) == NULL_RTX)
7235 /* Otherwise, start a sequence, initialize the information we have, and
7236 process all the insns we were given. */
7239 info.sp_equiv_reg = stack_pointer_rtx;
7241 info.equiv_reg_src = 0;
7245 while (insn != NULL_RTX)
7247 next = NEXT_INSN (insn);
7256 /* If this insn references the register that SP is equivalent to and
7257 we have a pending load to that register, we must force out the load
7258 first and then indicate we no longer know what SP's equivalent is. */
7259 if (info.equiv_reg_src != 0
7260 && reg_referenced_p (info.sp_equiv_reg, PATTERN (insn)))
7262 emit_equiv_load (&info);
7263 info.sp_equiv_reg = 0;
7266 info.new_sp_equiv_reg = info.sp_equiv_reg;
7267 info.new_sp_offset = info.sp_offset;
7269 /* If this is a (RETURN) and the return address is on the stack,
7270 update the address and change to an indirect jump. */
7271 if (GET_CODE (PATTERN (insn)) == RETURN
7272 || (GET_CODE (PATTERN (insn)) == PARALLEL
7273 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == RETURN))
7275 rtx retaddr = INCOMING_RETURN_ADDR_RTX;
7277 HOST_WIDE_INT offset = 0;
7278 rtx jump_insn, jump_set;
7280 /* If the return address is in a register, we can emit the insn
7281 unchanged. Otherwise, it must be a MEM and we see what the
7282 base register and offset are. In any case, we have to emit any
7283 pending load to the equivalent reg of SP, if any. */
7284 if (GET_CODE (retaddr) == REG)
7286 emit_equiv_load (&info);
7291 else if (GET_CODE (retaddr) == MEM
7292 && GET_CODE (XEXP (retaddr, 0)) == REG)
7293 base = gen_rtx_REG (Pmode, REGNO (XEXP (retaddr, 0))), offset = 0;
7294 else if (GET_CODE (retaddr) == MEM
7295 && GET_CODE (XEXP (retaddr, 0)) == PLUS
7296 && GET_CODE (XEXP (XEXP (retaddr, 0), 0)) == REG
7297 && GET_CODE (XEXP (XEXP (retaddr, 0), 1)) == CONST_INT)
7299 base = gen_rtx_REG (Pmode, REGNO (XEXP (XEXP (retaddr, 0), 0)));
7300 offset = INTVAL (XEXP (XEXP (retaddr, 0), 1));
7305 /* If the base of the location containing the return pointer
7306 is SP, we must update it with the replacement address. Otherwise,
7307 just build the necessary MEM. */
7308 retaddr = plus_constant (base, offset);
7309 if (base == stack_pointer_rtx)
7310 retaddr = simplify_replace_rtx (retaddr, stack_pointer_rtx,
7311 plus_constant (info.sp_equiv_reg,
7314 retaddr = gen_rtx_MEM (Pmode, retaddr);
7316 /* If there is a pending load to the equivalent register for SP
7317 and we reference that register, we must load our address into
7318 a scratch register and then do that load. */
7319 if (info.equiv_reg_src
7320 && reg_overlap_mentioned_p (info.equiv_reg_src, retaddr))
7325 for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
7326 if (HARD_REGNO_MODE_OK (regno, Pmode)
7327 && !fixed_regs[regno]
7328 && TEST_HARD_REG_BIT (regs_invalidated_by_call, regno)
7329 && !REGNO_REG_SET_P (EXIT_BLOCK_PTR->global_live_at_start,
7331 && !refers_to_regno_p (regno,
7332 regno + HARD_REGNO_NREGS (regno,
7334 info.equiv_reg_src, NULL))
7337 if (regno == FIRST_PSEUDO_REGISTER)
7340 reg = gen_rtx_REG (Pmode, regno);
7341 emit_move_insn (reg, retaddr);
7345 emit_equiv_load (&info);
7346 jump_insn = emit_jump_insn (gen_indirect_jump (retaddr));
7348 /* Show the SET in the above insn is a RETURN. */
7349 jump_set = single_set (jump_insn);
7353 SET_IS_RETURN_P (jump_set) = 1;
7356 /* If SP is not mentioned in the pattern and its equivalent register, if
7357 any, is not modified, just emit it. Otherwise, if neither is set,
7358 replace the reference to SP and emit the insn. If none of those are
7359 true, handle each SET individually. */
7360 else if (!reg_mentioned_p (stack_pointer_rtx, PATTERN (insn))
7361 && (info.sp_equiv_reg == stack_pointer_rtx
7362 || !reg_set_p (info.sp_equiv_reg, insn)))
7364 else if (! reg_set_p (stack_pointer_rtx, insn)
7365 && (info.sp_equiv_reg == stack_pointer_rtx
7366 || !reg_set_p (info.sp_equiv_reg, insn)))
7368 if (! validate_replace_rtx (stack_pointer_rtx,
7369 plus_constant (info.sp_equiv_reg,
7376 else if (GET_CODE (PATTERN (insn)) == SET)
7377 handle_epilogue_set (PATTERN (insn), &info);
7378 else if (GET_CODE (PATTERN (insn)) == PARALLEL)
7380 for (j = 0; j < XVECLEN (PATTERN (insn), 0); j++)
7381 if (GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET)
7382 handle_epilogue_set (XVECEXP (PATTERN (insn), 0, j), &info);
7387 info.sp_equiv_reg = info.new_sp_equiv_reg;
7388 info.sp_offset = info.new_sp_offset;
7393 insns = get_insns ();
7398 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
7399 structure that contains information about what we've seen so far. We
7400 process this SET by either updating that data or by emitting one or
7404 handle_epilogue_set (set, p)
7408 /* First handle the case where we are setting SP. Record what it is being
7409 set from. If unknown, abort. */
7410 if (reg_set_p (stack_pointer_rtx, set))
7412 if (SET_DEST (set) != stack_pointer_rtx)
7415 if (GET_CODE (SET_SRC (set)) == PLUS
7416 && GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT)
7418 p->new_sp_equiv_reg = XEXP (SET_SRC (set), 0);
7419 p->new_sp_offset = INTVAL (XEXP (SET_SRC (set), 1));
7422 p->new_sp_equiv_reg = SET_SRC (set), p->new_sp_offset = 0;
7424 /* If we are adjusting SP, we adjust from the old data. */
7425 if (p->new_sp_equiv_reg == stack_pointer_rtx)
7427 p->new_sp_equiv_reg = p->sp_equiv_reg;
7428 p->new_sp_offset += p->sp_offset;
7431 if (p->new_sp_equiv_reg == 0 || GET_CODE (p->new_sp_equiv_reg) != REG)
7437 /* Next handle the case where we are setting SP's equivalent register.
7438 If we already have a value to set it to, abort. We could update, but
7439 there seems little point in handling that case. Note that we have
7440 to allow for the case where we are setting the register set in
7441 the previous part of a PARALLEL inside a single insn. But use the
7442 old offset for any updates within this insn. */
7443 else if (p->new_sp_equiv_reg != 0 && reg_set_p (p->new_sp_equiv_reg, set))
7445 if (!rtx_equal_p (p->new_sp_equiv_reg, SET_DEST (set))
7446 || p->equiv_reg_src != 0)
7450 = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7451 plus_constant (p->sp_equiv_reg,
7455 /* Otherwise, replace any references to SP in the insn to its new value
7456 and emit the insn. */
7459 SET_SRC (set) = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7460 plus_constant (p->sp_equiv_reg,
7462 SET_DEST (set) = simplify_replace_rtx (SET_DEST (set), stack_pointer_rtx,
7463 plus_constant (p->sp_equiv_reg,
7469 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
7475 if (p->equiv_reg_src != 0)
7476 emit_move_insn (p->sp_equiv_reg, p->equiv_reg_src);
7478 p->equiv_reg_src = 0;
7482 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7483 this into place with notes indicating where the prologue ends and where
7484 the epilogue begins. Update the basic block information when possible. */
7487 thread_prologue_and_epilogue_insns (f)
7488 rtx f ATTRIBUTE_UNUSED;
7492 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
7495 #ifdef HAVE_prologue
7496 rtx prologue_end = NULL_RTX;
7498 #if defined (HAVE_epilogue) || defined(HAVE_return)
7499 rtx epilogue_end = NULL_RTX;
7502 #ifdef HAVE_prologue
7506 seq = gen_prologue ();
7509 /* Retain a map of the prologue insns. */
7510 record_insns (seq, &prologue);
7511 prologue_end = emit_note (NULL, NOTE_INSN_PROLOGUE_END);
7516 /* Can't deal with multiple successors of the entry block
7517 at the moment. Function should always have at least one
7519 if (!ENTRY_BLOCK_PTR->succ || ENTRY_BLOCK_PTR->succ->succ_next)
7522 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
7527 /* If the exit block has no non-fake predecessors, we don't need
7529 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7530 if ((e->flags & EDGE_FAKE) == 0)
7536 if (optimize && HAVE_return)
7538 /* If we're allowed to generate a simple return instruction,
7539 then by definition we don't need a full epilogue. Examine
7540 the block that falls through to EXIT. If it does not
7541 contain any code, examine its predecessors and try to
7542 emit (conditional) return instructions. */
7548 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7549 if (e->flags & EDGE_FALLTHRU)
7555 /* Verify that there are no active instructions in the last block. */
7557 while (label && GET_CODE (label) != CODE_LABEL)
7559 if (active_insn_p (label))
7561 label = PREV_INSN (label);
7564 if (last->head == label && GET_CODE (label) == CODE_LABEL)
7566 rtx epilogue_line_note = NULL_RTX;
7568 /* Locate the line number associated with the closing brace,
7569 if we can find one. */
7570 for (seq = get_last_insn ();
7571 seq && ! active_insn_p (seq);
7572 seq = PREV_INSN (seq))
7573 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
7575 epilogue_line_note = seq;
7579 for (e = last->pred; e; e = e_next)
7581 basic_block bb = e->src;
7584 e_next = e->pred_next;
7585 if (bb == ENTRY_BLOCK_PTR)
7589 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
7592 /* If we have an unconditional jump, we can replace that
7593 with a simple return instruction. */
7594 if (simplejump_p (jump))
7596 emit_return_into_block (bb, epilogue_line_note);
7600 /* If we have a conditional jump, we can try to replace
7601 that with a conditional return instruction. */
7602 else if (condjump_p (jump))
7604 if (! redirect_jump (jump, 0, 1))
7607 /* If this block has only one successor, it both jumps
7608 and falls through to the fallthru block, so we can't
7610 if (bb->succ->succ_next == NULL)
7616 /* Fix up the CFG for the successful change we just made. */
7617 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7620 /* Emit a return insn for the exit fallthru block. Whether
7621 this is still reachable will be determined later. */
7623 emit_barrier_after (last->end);
7624 emit_return_into_block (last, epilogue_line_note);
7625 epilogue_end = last->end;
7626 last->succ->flags &= ~EDGE_FALLTHRU;
7631 #ifdef HAVE_epilogue
7634 /* Find the edge that falls through to EXIT. Other edges may exist
7635 due to RETURN instructions, but those don't need epilogues.
7636 There really shouldn't be a mixture -- either all should have
7637 been converted or none, however... */
7639 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7640 if (e->flags & EDGE_FALLTHRU)
7646 epilogue_end = emit_note (NULL, NOTE_INSN_EPILOGUE_BEG);
7648 seq = gen_epilogue ();
7650 #ifdef INCOMING_RETURN_ADDR_RTX
7651 /* If this function returns with the stack depressed and we can support
7652 it, massage the epilogue to actually do that. */
7653 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7654 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7655 seq = keep_stack_depressed (seq);
7658 emit_jump_insn (seq);
7660 /* Retain a map of the epilogue insns. */
7661 record_insns (seq, &epilogue);
7666 insert_insn_on_edge (seq, e);
7673 commit_edge_insertions ();
7675 #ifdef HAVE_sibcall_epilogue
7676 /* Emit sibling epilogues before any sibling call sites. */
7677 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7679 basic_block bb = e->src;
7684 if (GET_CODE (insn) != CALL_INSN
7685 || ! SIBLING_CALL_P (insn))
7689 emit_insn (gen_sibcall_epilogue ());
7693 /* Retain a map of the epilogue insns. Used in life analysis to
7694 avoid getting rid of sibcall epilogue insns. Do this before we
7695 actually emit the sequence. */
7696 record_insns (seq, &sibcall_epilogue);
7698 i = PREV_INSN (insn);
7699 newinsn = emit_insn_before (seq, insn);
7703 #ifdef HAVE_prologue
7708 /* GDB handles `break f' by setting a breakpoint on the first
7709 line note after the prologue. Which means (1) that if
7710 there are line number notes before where we inserted the
7711 prologue we should move them, and (2) we should generate a
7712 note before the end of the first basic block, if there isn't
7715 ??? This behavior is completely broken when dealing with
7716 multiple entry functions. We simply place the note always
7717 into first basic block and let alternate entry points
7721 for (insn = prologue_end; insn; insn = prev)
7723 prev = PREV_INSN (insn);
7724 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7726 /* Note that we cannot reorder the first insn in the
7727 chain, since rest_of_compilation relies on that
7728 remaining constant. */
7731 reorder_insns (insn, insn, prologue_end);
7735 /* Find the last line number note in the first block. */
7736 for (insn = ENTRY_BLOCK_PTR->next_bb->end;
7737 insn != prologue_end && insn;
7738 insn = PREV_INSN (insn))
7739 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7742 /* If we didn't find one, make a copy of the first line number
7746 for (insn = next_active_insn (prologue_end);
7748 insn = PREV_INSN (insn))
7749 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7751 emit_line_note_after (NOTE_SOURCE_FILE (insn),
7752 NOTE_LINE_NUMBER (insn),
7759 #ifdef HAVE_epilogue
7764 /* Similarly, move any line notes that appear after the epilogue.
7765 There is no need, however, to be quite so anal about the existence
7767 for (insn = epilogue_end; insn; insn = next)
7769 next = NEXT_INSN (insn);
7770 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7771 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7777 /* Reposition the prologue-end and epilogue-begin notes after instruction
7778 scheduling and delayed branch scheduling. */
7781 reposition_prologue_and_epilogue_notes (f)
7782 rtx f ATTRIBUTE_UNUSED;
7784 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7785 rtx insn, last, note;
7788 if ((len = VARRAY_SIZE (prologue)) > 0)
7792 /* Scan from the beginning until we reach the last prologue insn.
7793 We apparently can't depend on basic_block_{head,end} after
7795 for (insn = f; insn; insn = NEXT_INSN (insn))
7797 if (GET_CODE (insn) == NOTE)
7799 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
7802 else if (contains (insn, prologue))
7812 /* Find the prologue-end note if we haven't already, and
7813 move it to just after the last prologue insn. */
7816 for (note = last; (note = NEXT_INSN (note));)
7817 if (GET_CODE (note) == NOTE
7818 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
7822 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
7823 if (GET_CODE (last) == CODE_LABEL)
7824 last = NEXT_INSN (last);
7825 reorder_insns (note, note, last);
7829 if ((len = VARRAY_SIZE (epilogue)) > 0)
7833 /* Scan from the end until we reach the first epilogue insn.
7834 We apparently can't depend on basic_block_{head,end} after
7836 for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
7838 if (GET_CODE (insn) == NOTE)
7840 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
7843 else if (contains (insn, epilogue))
7853 /* Find the epilogue-begin note if we haven't already, and
7854 move it to just before the first epilogue insn. */
7857 for (note = insn; (note = PREV_INSN (note));)
7858 if (GET_CODE (note) == NOTE
7859 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
7863 if (PREV_INSN (last) != note)
7864 reorder_insns (note, note, PREV_INSN (last));
7867 #endif /* HAVE_prologue or HAVE_epilogue */
7870 /* Called once, at initialization, to initialize function.c. */
7873 init_function_once ()
7875 VARRAY_INT_INIT (prologue, 0, "prologue");
7876 VARRAY_INT_INIT (epilogue, 0, "epilogue");
7877 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");
7880 #include "gt-function.h"