1 /* Expands front end tree to back end RTL for GCC.
2 Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
4 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
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. */
38 #include "coretypes.h"
49 #include "hard-reg-set.h"
50 #include "insn-config.h"
53 #include "basic-block.h"
58 #include "integrate.h"
59 #include "langhooks.h"
61 #include "cfglayout.h"
63 #include "tree-pass.h"
69 /* So we can assign to cfun in this file. */
72 #ifndef STACK_ALIGNMENT_NEEDED
73 #define STACK_ALIGNMENT_NEEDED 1
76 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
78 /* Some systems use __main in a way incompatible with its use in gcc, in these
79 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
80 give the same symbol without quotes for an alternative entry point. You
81 must define both, or neither. */
83 #define NAME__MAIN "__main"
86 /* Round a value to the lowest integer less than it that is a multiple of
87 the required alignment. Avoid using division in case the value is
88 negative. Assume the alignment is a power of two. */
89 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
91 /* Similar, but round to the next highest integer that meets the
93 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
95 /* Nonzero if function being compiled doesn't contain any calls
96 (ignoring the prologue and epilogue). This is set prior to
97 local register allocation and is valid for the remaining
99 int current_function_is_leaf;
101 /* Nonzero if function being compiled doesn't modify the stack pointer
102 (ignoring the prologue and epilogue). This is only valid after
103 pass_stack_ptr_mod has run. */
104 int current_function_sp_is_unchanging;
106 /* Nonzero if the function being compiled is a leaf function which only
107 uses leaf registers. This is valid after reload (specifically after
108 sched2) and is useful only if the port defines LEAF_REGISTERS. */
109 int current_function_uses_only_leaf_regs;
111 /* Nonzero once virtual register instantiation has been done.
112 assign_stack_local uses frame_pointer_rtx when this is nonzero.
113 calls.c:emit_library_call_value_1 uses it to set up
114 post-instantiation libcalls. */
115 int virtuals_instantiated;
117 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
118 static GTY(()) int funcdef_no;
120 /* These variables hold pointers to functions to create and destroy
121 target specific, per-function data structures. */
122 struct machine_function * (*init_machine_status) (void);
124 /* The currently compiled function. */
125 struct function *cfun = 0;
127 /* These hashes record the prologue and epilogue insns. */
128 static GTY((if_marked ("ggc_marked_p"), param_is (struct rtx_def)))
129 htab_t prologue_insn_hash;
130 static GTY((if_marked ("ggc_marked_p"), param_is (struct rtx_def)))
131 htab_t epilogue_insn_hash;
134 htab_t types_used_by_vars_hash = NULL;
135 tree types_used_by_cur_var_decl = NULL;
137 /* Forward declarations. */
139 static struct temp_slot *find_temp_slot_from_address (rtx);
140 static void pad_to_arg_alignment (struct args_size *, int, struct args_size *);
141 static void pad_below (struct args_size *, enum machine_mode, tree);
142 static void reorder_blocks_1 (rtx, tree, VEC(tree,heap) **);
143 static int all_blocks (tree, tree *);
144 static tree *get_block_vector (tree, int *);
145 extern tree debug_find_var_in_block_tree (tree, tree);
146 /* We always define `record_insns' even if it's not used so that we
147 can always export `prologue_epilogue_contains'. */
148 static void record_insns (rtx, rtx, htab_t *) ATTRIBUTE_UNUSED;
149 static bool contains (const_rtx, htab_t);
151 static void emit_return_into_block (basic_block);
153 static void prepare_function_start (void);
154 static void do_clobber_return_reg (rtx, void *);
155 static void do_use_return_reg (rtx, void *);
156 static void set_insn_locators (rtx, int) ATTRIBUTE_UNUSED;
158 /* Stack of nested functions. */
159 /* Keep track of the cfun stack. */
161 typedef struct function *function_p;
163 DEF_VEC_P(function_p);
164 DEF_VEC_ALLOC_P(function_p,heap);
165 static VEC(function_p,heap) *function_context_stack;
167 /* Save the current context for compilation of a nested function.
168 This is called from language-specific code. */
171 push_function_context (void)
174 allocate_struct_function (NULL, false);
176 VEC_safe_push (function_p, heap, function_context_stack, cfun);
180 /* Restore the last saved context, at the end of a nested function.
181 This function is called from language-specific code. */
184 pop_function_context (void)
186 struct function *p = VEC_pop (function_p, function_context_stack);
188 current_function_decl = p->decl;
190 /* Reset variables that have known state during rtx generation. */
191 virtuals_instantiated = 0;
192 generating_concat_p = 1;
195 /* Clear out all parts of the state in F that can safely be discarded
196 after the function has been parsed, but not compiled, to let
197 garbage collection reclaim the memory. */
200 free_after_parsing (struct function *f)
205 /* Clear out all parts of the state in F that can safely be discarded
206 after the function has been compiled, to let garbage collection
207 reclaim the memory. */
210 free_after_compilation (struct function *f)
212 prologue_insn_hash = NULL;
213 epilogue_insn_hash = NULL;
215 if (crtl->emit.regno_pointer_align)
216 free (crtl->emit.regno_pointer_align);
218 memset (crtl, 0, sizeof (struct rtl_data));
223 regno_reg_rtx = NULL;
224 insn_locators_free ();
227 /* Return size needed for stack frame based on slots so far allocated.
228 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
229 the caller may have to do that. */
232 get_frame_size (void)
234 if (FRAME_GROWS_DOWNWARD)
235 return -frame_offset;
240 /* Issue an error message and return TRUE if frame OFFSET overflows in
241 the signed target pointer arithmetics for function FUNC. Otherwise
245 frame_offset_overflow (HOST_WIDE_INT offset, tree func)
247 unsigned HOST_WIDE_INT size = FRAME_GROWS_DOWNWARD ? -offset : offset;
249 if (size > ((unsigned HOST_WIDE_INT) 1 << (GET_MODE_BITSIZE (Pmode) - 1))
250 /* Leave room for the fixed part of the frame. */
251 - 64 * UNITS_PER_WORD)
253 error_at (DECL_SOURCE_LOCATION (func),
254 "total size of local objects too large");
261 /* Return stack slot alignment in bits for TYPE and MODE. */
264 get_stack_local_alignment (tree type, enum machine_mode mode)
266 unsigned int alignment;
269 alignment = BIGGEST_ALIGNMENT;
271 alignment = GET_MODE_ALIGNMENT (mode);
273 /* Allow the frond-end to (possibly) increase the alignment of this
276 type = lang_hooks.types.type_for_mode (mode, 0);
278 return STACK_SLOT_ALIGNMENT (type, mode, alignment);
281 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
282 with machine mode MODE.
284 ALIGN controls the amount of alignment for the address of the slot:
285 0 means according to MODE,
286 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
287 -2 means use BITS_PER_UNIT,
288 positive specifies alignment boundary in bits.
290 If REDUCE_ALIGNMENT_OK is true, it is OK to reduce alignment.
292 We do not round to stack_boundary here. */
295 assign_stack_local_1 (enum machine_mode mode, HOST_WIDE_INT size,
297 bool reduce_alignment_ok ATTRIBUTE_UNUSED)
300 int bigend_correction = 0;
301 unsigned int alignment, alignment_in_bits;
302 int frame_off, frame_alignment, frame_phase;
306 alignment = get_stack_local_alignment (NULL, mode);
307 alignment /= BITS_PER_UNIT;
309 else if (align == -1)
311 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
312 size = CEIL_ROUND (size, alignment);
314 else if (align == -2)
315 alignment = 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
317 alignment = align / BITS_PER_UNIT;
319 alignment_in_bits = alignment * BITS_PER_UNIT;
321 if (FRAME_GROWS_DOWNWARD)
322 frame_offset -= size;
324 /* Ignore alignment if it exceeds MAX_SUPPORTED_STACK_ALIGNMENT. */
325 if (alignment_in_bits > MAX_SUPPORTED_STACK_ALIGNMENT)
327 alignment_in_bits = MAX_SUPPORTED_STACK_ALIGNMENT;
328 alignment = alignment_in_bits / BITS_PER_UNIT;
331 if (SUPPORTS_STACK_ALIGNMENT)
333 if (crtl->stack_alignment_estimated < alignment_in_bits)
335 if (!crtl->stack_realign_processed)
336 crtl->stack_alignment_estimated = alignment_in_bits;
339 /* If stack is realigned and stack alignment value
340 hasn't been finalized, it is OK not to increase
341 stack_alignment_estimated. The bigger alignment
342 requirement is recorded in stack_alignment_needed
344 gcc_assert (!crtl->stack_realign_finalized);
345 if (!crtl->stack_realign_needed)
347 /* It is OK to reduce the alignment as long as the
348 requested size is 0 or the estimated stack
349 alignment >= mode alignment. */
350 gcc_assert (reduce_alignment_ok
352 || (crtl->stack_alignment_estimated
353 >= GET_MODE_ALIGNMENT (mode)));
354 alignment_in_bits = crtl->stack_alignment_estimated;
355 alignment = alignment_in_bits / BITS_PER_UNIT;
361 if (crtl->stack_alignment_needed < alignment_in_bits)
362 crtl->stack_alignment_needed = alignment_in_bits;
363 if (crtl->max_used_stack_slot_alignment < alignment_in_bits)
364 crtl->max_used_stack_slot_alignment = alignment_in_bits;
366 /* Calculate how many bytes the start of local variables is off from
368 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
369 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
370 frame_phase = frame_off ? frame_alignment - frame_off : 0;
372 /* Round the frame offset to the specified alignment. The default is
373 to always honor requests to align the stack but a port may choose to
374 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
375 if (STACK_ALIGNMENT_NEEDED
379 /* We must be careful here, since FRAME_OFFSET might be negative and
380 division with a negative dividend isn't as well defined as we might
381 like. So we instead assume that ALIGNMENT is a power of two and
382 use logical operations which are unambiguous. */
383 if (FRAME_GROWS_DOWNWARD)
385 = (FLOOR_ROUND (frame_offset - frame_phase,
386 (unsigned HOST_WIDE_INT) alignment)
390 = (CEIL_ROUND (frame_offset - frame_phase,
391 (unsigned HOST_WIDE_INT) alignment)
395 /* On a big-endian machine, if we are allocating more space than we will use,
396 use the least significant bytes of those that are allocated. */
397 if (BYTES_BIG_ENDIAN && mode != BLKmode && GET_MODE_SIZE (mode) < size)
398 bigend_correction = size - GET_MODE_SIZE (mode);
400 /* If we have already instantiated virtual registers, return the actual
401 address relative to the frame pointer. */
402 if (virtuals_instantiated)
403 addr = plus_constant (frame_pointer_rtx,
405 (frame_offset + bigend_correction
406 + STARTING_FRAME_OFFSET, Pmode));
408 addr = plus_constant (virtual_stack_vars_rtx,
410 (frame_offset + bigend_correction,
413 if (!FRAME_GROWS_DOWNWARD)
414 frame_offset += size;
416 x = gen_rtx_MEM (mode, addr);
417 set_mem_align (x, alignment_in_bits);
418 MEM_NOTRAP_P (x) = 1;
421 = gen_rtx_EXPR_LIST (VOIDmode, x, stack_slot_list);
423 if (frame_offset_overflow (frame_offset, current_function_decl))
429 /* Wrap up assign_stack_local_1 with last parameter as false. */
432 assign_stack_local (enum machine_mode mode, HOST_WIDE_INT size, int align)
434 return assign_stack_local_1 (mode, size, align, false);
438 /* In order to evaluate some expressions, such as function calls returning
439 structures in memory, we need to temporarily allocate stack locations.
440 We record each allocated temporary in the following structure.
442 Associated with each temporary slot is a nesting level. When we pop up
443 one level, all temporaries associated with the previous level are freed.
444 Normally, all temporaries are freed after the execution of the statement
445 in which they were created. However, if we are inside a ({...}) grouping,
446 the result may be in a temporary and hence must be preserved. If the
447 result could be in a temporary, we preserve it if we can determine which
448 one it is in. If we cannot determine which temporary may contain the
449 result, all temporaries are preserved. A temporary is preserved by
450 pretending it was allocated at the previous nesting level.
452 Automatic variables are also assigned temporary slots, at the nesting
453 level where they are defined. They are marked a "kept" so that
454 free_temp_slots will not free them. */
456 struct GTY(()) temp_slot {
457 /* Points to next temporary slot. */
458 struct temp_slot *next;
459 /* Points to previous temporary slot. */
460 struct temp_slot *prev;
461 /* The rtx to used to reference the slot. */
463 /* The size, in units, of the slot. */
465 /* The type of the object in the slot, or zero if it doesn't correspond
466 to a type. We use this to determine whether a slot can be reused.
467 It can be reused if objects of the type of the new slot will always
468 conflict with objects of the type of the old slot. */
470 /* The alignment (in bits) of the slot. */
472 /* Nonzero if this temporary is currently in use. */
474 /* Nonzero if this temporary has its address taken. */
476 /* Nesting level at which this slot is being used. */
478 /* Nonzero if this should survive a call to free_temp_slots. */
480 /* The offset of the slot from the frame_pointer, including extra space
481 for alignment. This info is for combine_temp_slots. */
482 HOST_WIDE_INT base_offset;
483 /* The size of the slot, including extra space for alignment. This
484 info is for combine_temp_slots. */
485 HOST_WIDE_INT full_size;
488 /* A table of addresses that represent a stack slot. The table is a mapping
489 from address RTXen to a temp slot. */
490 static GTY((param_is(struct temp_slot_address_entry))) htab_t temp_slot_address_table;
492 /* Entry for the above hash table. */
493 struct GTY(()) temp_slot_address_entry {
496 struct temp_slot *temp_slot;
499 /* Removes temporary slot TEMP from LIST. */
502 cut_slot_from_list (struct temp_slot *temp, struct temp_slot **list)
505 temp->next->prev = temp->prev;
507 temp->prev->next = temp->next;
511 temp->prev = temp->next = NULL;
514 /* Inserts temporary slot TEMP to LIST. */
517 insert_slot_to_list (struct temp_slot *temp, struct temp_slot **list)
521 (*list)->prev = temp;
526 /* Returns the list of used temp slots at LEVEL. */
528 static struct temp_slot **
529 temp_slots_at_level (int level)
531 if (level >= (int) VEC_length (temp_slot_p, used_temp_slots))
532 VEC_safe_grow_cleared (temp_slot_p, gc, used_temp_slots, level + 1);
534 return &(VEC_address (temp_slot_p, used_temp_slots)[level]);
537 /* Returns the maximal temporary slot level. */
540 max_slot_level (void)
542 if (!used_temp_slots)
545 return VEC_length (temp_slot_p, used_temp_slots) - 1;
548 /* Moves temporary slot TEMP to LEVEL. */
551 move_slot_to_level (struct temp_slot *temp, int level)
553 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
554 insert_slot_to_list (temp, temp_slots_at_level (level));
558 /* Make temporary slot TEMP available. */
561 make_slot_available (struct temp_slot *temp)
563 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
564 insert_slot_to_list (temp, &avail_temp_slots);
569 /* Compute the hash value for an address -> temp slot mapping.
570 The value is cached on the mapping entry. */
572 temp_slot_address_compute_hash (struct temp_slot_address_entry *t)
574 int do_not_record = 0;
575 return hash_rtx (t->address, GET_MODE (t->address),
576 &do_not_record, NULL, false);
579 /* Return the hash value for an address -> temp slot mapping. */
581 temp_slot_address_hash (const void *p)
583 const struct temp_slot_address_entry *t;
584 t = (const struct temp_slot_address_entry *) p;
588 /* Compare two address -> temp slot mapping entries. */
590 temp_slot_address_eq (const void *p1, const void *p2)
592 const struct temp_slot_address_entry *t1, *t2;
593 t1 = (const struct temp_slot_address_entry *) p1;
594 t2 = (const struct temp_slot_address_entry *) p2;
595 return exp_equiv_p (t1->address, t2->address, 0, true);
598 /* Add ADDRESS as an alias of TEMP_SLOT to the addess -> temp slot mapping. */
600 insert_temp_slot_address (rtx address, struct temp_slot *temp_slot)
603 struct temp_slot_address_entry *t = GGC_NEW (struct temp_slot_address_entry);
604 t->address = address;
605 t->temp_slot = temp_slot;
606 t->hash = temp_slot_address_compute_hash (t);
607 slot = htab_find_slot_with_hash (temp_slot_address_table, t, t->hash, INSERT);
611 /* Remove an address -> temp slot mapping entry if the temp slot is
612 not in use anymore. Callback for remove_unused_temp_slot_addresses. */
614 remove_unused_temp_slot_addresses_1 (void **slot, void *data ATTRIBUTE_UNUSED)
616 const struct temp_slot_address_entry *t;
617 t = (const struct temp_slot_address_entry *) *slot;
618 if (! t->temp_slot->in_use)
623 /* Remove all mappings of addresses to unused temp slots. */
625 remove_unused_temp_slot_addresses (void)
627 htab_traverse (temp_slot_address_table,
628 remove_unused_temp_slot_addresses_1,
632 /* Find the temp slot corresponding to the object at address X. */
634 static struct temp_slot *
635 find_temp_slot_from_address (rtx x)
638 struct temp_slot_address_entry tmp, *t;
640 /* First try the easy way:
641 See if X exists in the address -> temp slot mapping. */
643 tmp.temp_slot = NULL;
644 tmp.hash = temp_slot_address_compute_hash (&tmp);
645 t = (struct temp_slot_address_entry *)
646 htab_find_with_hash (temp_slot_address_table, &tmp, tmp.hash);
650 /* If we have a sum involving a register, see if it points to a temp
652 if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 0))
653 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
655 else if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 1))
656 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
659 /* Last resort: Address is a virtual stack var address. */
660 if (GET_CODE (x) == PLUS
661 && XEXP (x, 0) == virtual_stack_vars_rtx
662 && CONST_INT_P (XEXP (x, 1)))
665 for (i = max_slot_level (); i >= 0; i--)
666 for (p = *temp_slots_at_level (i); p; p = p->next)
668 if (INTVAL (XEXP (x, 1)) >= p->base_offset
669 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size)
677 /* Allocate a temporary stack slot and record it for possible later
680 MODE is the machine mode to be given to the returned rtx.
682 SIZE is the size in units of the space required. We do no rounding here
683 since assign_stack_local will do any required rounding.
685 KEEP is 1 if this slot is to be retained after a call to
686 free_temp_slots. Automatic variables for a block are allocated
687 with this flag. KEEP values of 2 or 3 were needed respectively
688 for variables whose lifetime is controlled by CLEANUP_POINT_EXPRs
689 or for SAVE_EXPRs, but they are now unused.
691 TYPE is the type that will be used for the stack slot. */
694 assign_stack_temp_for_type (enum machine_mode mode, HOST_WIDE_INT size,
698 struct temp_slot *p, *best_p = 0, *selected = NULL, **pp;
701 /* If SIZE is -1 it means that somebody tried to allocate a temporary
702 of a variable size. */
703 gcc_assert (size != -1);
705 /* These are now unused. */
706 gcc_assert (keep <= 1);
708 align = get_stack_local_alignment (type, mode);
710 /* Try to find an available, already-allocated temporary of the proper
711 mode which meets the size and alignment requirements. Choose the
712 smallest one with the closest alignment.
714 If assign_stack_temp is called outside of the tree->rtl expansion,
715 we cannot reuse the stack slots (that may still refer to
716 VIRTUAL_STACK_VARS_REGNUM). */
717 if (!virtuals_instantiated)
719 for (p = avail_temp_slots; p; p = p->next)
721 if (p->align >= align && p->size >= size
722 && GET_MODE (p->slot) == mode
723 && objects_must_conflict_p (p->type, type)
724 && (best_p == 0 || best_p->size > p->size
725 || (best_p->size == p->size && best_p->align > p->align)))
727 if (p->align == align && p->size == size)
730 cut_slot_from_list (selected, &avail_temp_slots);
739 /* Make our best, if any, the one to use. */
743 cut_slot_from_list (selected, &avail_temp_slots);
745 /* If there are enough aligned bytes left over, make them into a new
746 temp_slot so that the extra bytes don't get wasted. Do this only
747 for BLKmode slots, so that we can be sure of the alignment. */
748 if (GET_MODE (best_p->slot) == BLKmode)
750 int alignment = best_p->align / BITS_PER_UNIT;
751 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
753 if (best_p->size - rounded_size >= alignment)
755 p = GGC_NEW (struct temp_slot);
756 p->in_use = p->addr_taken = 0;
757 p->size = best_p->size - rounded_size;
758 p->base_offset = best_p->base_offset + rounded_size;
759 p->full_size = best_p->full_size - rounded_size;
760 p->slot = adjust_address_nv (best_p->slot, BLKmode, rounded_size);
761 p->align = best_p->align;
762 p->type = best_p->type;
763 insert_slot_to_list (p, &avail_temp_slots);
765 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
768 best_p->size = rounded_size;
769 best_p->full_size = rounded_size;
774 /* If we still didn't find one, make a new temporary. */
777 HOST_WIDE_INT frame_offset_old = frame_offset;
779 p = GGC_NEW (struct temp_slot);
781 /* We are passing an explicit alignment request to assign_stack_local.
782 One side effect of that is assign_stack_local will not round SIZE
783 to ensure the frame offset remains suitably aligned.
785 So for requests which depended on the rounding of SIZE, we go ahead
786 and round it now. We also make sure ALIGNMENT is at least
787 BIGGEST_ALIGNMENT. */
788 gcc_assert (mode != BLKmode || align == BIGGEST_ALIGNMENT);
789 p->slot = assign_stack_local (mode,
791 ? CEIL_ROUND (size, (int) align / BITS_PER_UNIT)
797 /* The following slot size computation is necessary because we don't
798 know the actual size of the temporary slot until assign_stack_local
799 has performed all the frame alignment and size rounding for the
800 requested temporary. Note that extra space added for alignment
801 can be either above or below this stack slot depending on which
802 way the frame grows. We include the extra space if and only if it
803 is above this slot. */
804 if (FRAME_GROWS_DOWNWARD)
805 p->size = frame_offset_old - frame_offset;
809 /* Now define the fields used by combine_temp_slots. */
810 if (FRAME_GROWS_DOWNWARD)
812 p->base_offset = frame_offset;
813 p->full_size = frame_offset_old - frame_offset;
817 p->base_offset = frame_offset_old;
818 p->full_size = frame_offset - frame_offset_old;
828 p->level = temp_slot_level;
831 pp = temp_slots_at_level (p->level);
832 insert_slot_to_list (p, pp);
833 insert_temp_slot_address (XEXP (p->slot, 0), p);
835 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
836 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
837 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list);
839 /* If we know the alias set for the memory that will be used, use
840 it. If there's no TYPE, then we don't know anything about the
841 alias set for the memory. */
842 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
843 set_mem_align (slot, align);
845 /* If a type is specified, set the relevant flags. */
848 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
849 MEM_SET_IN_STRUCT_P (slot, (AGGREGATE_TYPE_P (type)
850 || TREE_CODE (type) == COMPLEX_TYPE));
852 MEM_NOTRAP_P (slot) = 1;
857 /* Allocate a temporary stack slot and record it for possible later
858 reuse. First three arguments are same as in preceding function. */
861 assign_stack_temp (enum machine_mode mode, HOST_WIDE_INT size, int keep)
863 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
866 /* Assign a temporary.
867 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
868 and so that should be used in error messages. In either case, we
869 allocate of the given type.
870 KEEP is as for assign_stack_temp.
871 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
872 it is 0 if a register is OK.
873 DONT_PROMOTE is 1 if we should not promote values in register
877 assign_temp (tree type_or_decl, int keep, int memory_required,
878 int dont_promote ATTRIBUTE_UNUSED)
881 enum machine_mode mode;
886 if (DECL_P (type_or_decl))
887 decl = type_or_decl, type = TREE_TYPE (decl);
889 decl = NULL, type = type_or_decl;
891 mode = TYPE_MODE (type);
893 unsignedp = TYPE_UNSIGNED (type);
896 if (mode == BLKmode || memory_required)
898 HOST_WIDE_INT size = int_size_in_bytes (type);
901 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
902 problems with allocating the stack space. */
906 /* Unfortunately, we don't yet know how to allocate variable-sized
907 temporaries. However, sometimes we can find a fixed upper limit on
908 the size, so try that instead. */
910 size = max_int_size_in_bytes (type);
912 /* The size of the temporary may be too large to fit into an integer. */
913 /* ??? Not sure this should happen except for user silliness, so limit
914 this to things that aren't compiler-generated temporaries. The
915 rest of the time we'll die in assign_stack_temp_for_type. */
916 if (decl && size == -1
917 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
919 error ("size of variable %q+D is too large", decl);
923 tmp = assign_stack_temp_for_type (mode, size, keep, type);
929 mode = promote_mode (type, mode, &unsignedp);
932 return gen_reg_rtx (mode);
935 /* Combine temporary stack slots which are adjacent on the stack.
937 This allows for better use of already allocated stack space. This is only
938 done for BLKmode slots because we can be sure that we won't have alignment
939 problems in this case. */
942 combine_temp_slots (void)
944 struct temp_slot *p, *q, *next, *next_q;
947 /* We can't combine slots, because the information about which slot
948 is in which alias set will be lost. */
949 if (flag_strict_aliasing)
952 /* If there are a lot of temp slots, don't do anything unless
953 high levels of optimization. */
954 if (! flag_expensive_optimizations)
955 for (p = avail_temp_slots, num_slots = 0; p; p = p->next, num_slots++)
956 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
959 for (p = avail_temp_slots; p; p = next)
965 if (GET_MODE (p->slot) != BLKmode)
968 for (q = p->next; q; q = next_q)
974 if (GET_MODE (q->slot) != BLKmode)
977 if (p->base_offset + p->full_size == q->base_offset)
979 /* Q comes after P; combine Q into P. */
981 p->full_size += q->full_size;
984 else if (q->base_offset + q->full_size == p->base_offset)
986 /* P comes after Q; combine P into Q. */
988 q->full_size += p->full_size;
993 cut_slot_from_list (q, &avail_temp_slots);
996 /* Either delete P or advance past it. */
998 cut_slot_from_list (p, &avail_temp_slots);
1002 /* Indicate that NEW_RTX is an alternate way of referring to the temp
1003 slot that previously was known by OLD_RTX. */
1006 update_temp_slot_address (rtx old_rtx, rtx new_rtx)
1008 struct temp_slot *p;
1010 if (rtx_equal_p (old_rtx, new_rtx))
1013 p = find_temp_slot_from_address (old_rtx);
1015 /* If we didn't find one, see if both OLD_RTX is a PLUS. If so, and
1016 NEW_RTX is a register, see if one operand of the PLUS is a
1017 temporary location. If so, NEW_RTX points into it. Otherwise,
1018 if both OLD_RTX and NEW_RTX are a PLUS and if there is a register
1019 in common between them. If so, try a recursive call on those
1023 if (GET_CODE (old_rtx) != PLUS)
1026 if (REG_P (new_rtx))
1028 update_temp_slot_address (XEXP (old_rtx, 0), new_rtx);
1029 update_temp_slot_address (XEXP (old_rtx, 1), new_rtx);
1032 else if (GET_CODE (new_rtx) != PLUS)
1035 if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 0)))
1036 update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 1));
1037 else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 0)))
1038 update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 1));
1039 else if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 1)))
1040 update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 0));
1041 else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 1)))
1042 update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 0));
1047 /* Otherwise add an alias for the temp's address. */
1048 insert_temp_slot_address (new_rtx, p);
1051 /* If X could be a reference to a temporary slot, mark the fact that its
1052 address was taken. */
1055 mark_temp_addr_taken (rtx x)
1057 struct temp_slot *p;
1062 /* If X is not in memory or is at a constant address, it cannot be in
1063 a temporary slot. */
1064 if (!MEM_P (x) || CONSTANT_P (XEXP (x, 0)))
1067 p = find_temp_slot_from_address (XEXP (x, 0));
1072 /* If X could be a reference to a temporary slot, mark that slot as
1073 belonging to the to one level higher than the current level. If X
1074 matched one of our slots, just mark that one. Otherwise, we can't
1075 easily predict which it is, so upgrade all of them. Kept slots
1076 need not be touched.
1078 This is called when an ({...}) construct occurs and a statement
1079 returns a value in memory. */
1082 preserve_temp_slots (rtx x)
1084 struct temp_slot *p = 0, *next;
1086 /* If there is no result, we still might have some objects whose address
1087 were taken, so we need to make sure they stay around. */
1090 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1095 move_slot_to_level (p, temp_slot_level - 1);
1101 /* If X is a register that is being used as a pointer, see if we have
1102 a temporary slot we know it points to. To be consistent with
1103 the code below, we really should preserve all non-kept slots
1104 if we can't find a match, but that seems to be much too costly. */
1105 if (REG_P (x) && REG_POINTER (x))
1106 p = find_temp_slot_from_address (x);
1108 /* If X is not in memory or is at a constant address, it cannot be in
1109 a temporary slot, but it can contain something whose address was
1111 if (p == 0 && (!MEM_P (x) || CONSTANT_P (XEXP (x, 0))))
1113 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1118 move_slot_to_level (p, temp_slot_level - 1);
1124 /* First see if we can find a match. */
1126 p = find_temp_slot_from_address (XEXP (x, 0));
1130 /* Move everything at our level whose address was taken to our new
1131 level in case we used its address. */
1132 struct temp_slot *q;
1134 if (p->level == temp_slot_level)
1136 for (q = *temp_slots_at_level (temp_slot_level); q; q = next)
1140 if (p != q && q->addr_taken)
1141 move_slot_to_level (q, temp_slot_level - 1);
1144 move_slot_to_level (p, temp_slot_level - 1);
1150 /* Otherwise, preserve all non-kept slots at this level. */
1151 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1156 move_slot_to_level (p, temp_slot_level - 1);
1160 /* Free all temporaries used so far. This is normally called at the
1161 end of generating code for a statement. */
1164 free_temp_slots (void)
1166 struct temp_slot *p, *next;
1167 bool some_available = false;
1169 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1175 make_slot_available (p);
1176 some_available = true;
1182 remove_unused_temp_slot_addresses ();
1183 combine_temp_slots ();
1187 /* Push deeper into the nesting level for stack temporaries. */
1190 push_temp_slots (void)
1195 /* Pop a temporary nesting level. All slots in use in the current level
1199 pop_temp_slots (void)
1201 struct temp_slot *p, *next;
1202 bool some_available = false;
1204 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1207 make_slot_available (p);
1208 some_available = true;
1213 remove_unused_temp_slot_addresses ();
1214 combine_temp_slots ();
1220 /* Initialize temporary slots. */
1223 init_temp_slots (void)
1225 /* We have not allocated any temporaries yet. */
1226 avail_temp_slots = 0;
1227 used_temp_slots = 0;
1228 temp_slot_level = 0;
1230 /* Set up the table to map addresses to temp slots. */
1231 if (! temp_slot_address_table)
1232 temp_slot_address_table = htab_create_ggc (32,
1233 temp_slot_address_hash,
1234 temp_slot_address_eq,
1237 htab_empty (temp_slot_address_table);
1240 /* These routines are responsible for converting virtual register references
1241 to the actual hard register references once RTL generation is complete.
1243 The following four variables are used for communication between the
1244 routines. They contain the offsets of the virtual registers from their
1245 respective hard registers. */
1247 static int in_arg_offset;
1248 static int var_offset;
1249 static int dynamic_offset;
1250 static int out_arg_offset;
1251 static int cfa_offset;
1253 /* In most machines, the stack pointer register is equivalent to the bottom
1256 #ifndef STACK_POINTER_OFFSET
1257 #define STACK_POINTER_OFFSET 0
1260 /* If not defined, pick an appropriate default for the offset of dynamically
1261 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1262 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1264 #ifndef STACK_DYNAMIC_OFFSET
1266 /* The bottom of the stack points to the actual arguments. If
1267 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1268 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1269 stack space for register parameters is not pushed by the caller, but
1270 rather part of the fixed stack areas and hence not included in
1271 `crtl->outgoing_args_size'. Nevertheless, we must allow
1272 for it when allocating stack dynamic objects. */
1274 #if defined(REG_PARM_STACK_SPACE)
1275 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1276 ((ACCUMULATE_OUTGOING_ARGS \
1277 ? (crtl->outgoing_args_size \
1278 + (OUTGOING_REG_PARM_STACK_SPACE ((!(FNDECL) ? NULL_TREE : TREE_TYPE (FNDECL))) ? 0 \
1279 : REG_PARM_STACK_SPACE (FNDECL))) \
1280 : 0) + (STACK_POINTER_OFFSET))
1282 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1283 ((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : 0) \
1284 + (STACK_POINTER_OFFSET))
1289 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1290 is a virtual register, return the equivalent hard register and set the
1291 offset indirectly through the pointer. Otherwise, return 0. */
1294 instantiate_new_reg (rtx x, HOST_WIDE_INT *poffset)
1297 HOST_WIDE_INT offset;
1299 if (x == virtual_incoming_args_rtx)
1301 if (stack_realign_drap)
1303 /* Replace virtual_incoming_args_rtx with internal arg
1304 pointer if DRAP is used to realign stack. */
1305 new_rtx = crtl->args.internal_arg_pointer;
1309 new_rtx = arg_pointer_rtx, offset = in_arg_offset;
1311 else if (x == virtual_stack_vars_rtx)
1312 new_rtx = frame_pointer_rtx, offset = var_offset;
1313 else if (x == virtual_stack_dynamic_rtx)
1314 new_rtx = stack_pointer_rtx, offset = dynamic_offset;
1315 else if (x == virtual_outgoing_args_rtx)
1316 new_rtx = stack_pointer_rtx, offset = out_arg_offset;
1317 else if (x == virtual_cfa_rtx)
1319 #ifdef FRAME_POINTER_CFA_OFFSET
1320 new_rtx = frame_pointer_rtx;
1322 new_rtx = arg_pointer_rtx;
1324 offset = cfa_offset;
1333 /* A subroutine of instantiate_virtual_regs, called via for_each_rtx.
1334 Instantiate any virtual registers present inside of *LOC. The expression
1335 is simplified, as much as possible, but is not to be considered "valid"
1336 in any sense implied by the target. If any change is made, set CHANGED
1340 instantiate_virtual_regs_in_rtx (rtx *loc, void *data)
1342 HOST_WIDE_INT offset;
1343 bool *changed = (bool *) data;
1350 switch (GET_CODE (x))
1353 new_rtx = instantiate_new_reg (x, &offset);
1356 *loc = plus_constant (new_rtx, offset);
1363 new_rtx = instantiate_new_reg (XEXP (x, 0), &offset);
1366 new_rtx = plus_constant (new_rtx, offset);
1367 *loc = simplify_gen_binary (PLUS, GET_MODE (x), new_rtx, XEXP (x, 1));
1373 /* FIXME -- from old code */
1374 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1375 we can commute the PLUS and SUBREG because pointers into the
1376 frame are well-behaved. */
1386 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1387 matches the predicate for insn CODE operand OPERAND. */
1390 safe_insn_predicate (int code, int operand, rtx x)
1392 const struct insn_operand_data *op_data;
1397 op_data = &insn_data[code].operand[operand];
1398 if (op_data->predicate == NULL)
1401 return op_data->predicate (x, op_data->mode);
1404 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1405 registers present inside of insn. The result will be a valid insn. */
1408 instantiate_virtual_regs_in_insn (rtx insn)
1410 HOST_WIDE_INT offset;
1412 bool any_change = false;
1413 rtx set, new_rtx, x, seq;
1415 /* There are some special cases to be handled first. */
1416 set = single_set (insn);
1419 /* We're allowed to assign to a virtual register. This is interpreted
1420 to mean that the underlying register gets assigned the inverse
1421 transformation. This is used, for example, in the handling of
1423 new_rtx = instantiate_new_reg (SET_DEST (set), &offset);
1428 for_each_rtx (&SET_SRC (set), instantiate_virtual_regs_in_rtx, NULL);
1429 x = simplify_gen_binary (PLUS, GET_MODE (new_rtx), SET_SRC (set),
1431 x = force_operand (x, new_rtx);
1433 emit_move_insn (new_rtx, x);
1438 emit_insn_before (seq, insn);
1443 /* Handle a straight copy from a virtual register by generating a
1444 new add insn. The difference between this and falling through
1445 to the generic case is avoiding a new pseudo and eliminating a
1446 move insn in the initial rtl stream. */
1447 new_rtx = instantiate_new_reg (SET_SRC (set), &offset);
1448 if (new_rtx && offset != 0
1449 && REG_P (SET_DEST (set))
1450 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1454 x = expand_simple_binop (GET_MODE (SET_DEST (set)), PLUS,
1455 new_rtx, GEN_INT (offset), SET_DEST (set),
1456 1, OPTAB_LIB_WIDEN);
1457 if (x != SET_DEST (set))
1458 emit_move_insn (SET_DEST (set), x);
1463 emit_insn_before (seq, insn);
1468 extract_insn (insn);
1469 insn_code = INSN_CODE (insn);
1471 /* Handle a plus involving a virtual register by determining if the
1472 operands remain valid if they're modified in place. */
1473 if (GET_CODE (SET_SRC (set)) == PLUS
1474 && recog_data.n_operands >= 3
1475 && recog_data.operand_loc[1] == &XEXP (SET_SRC (set), 0)
1476 && recog_data.operand_loc[2] == &XEXP (SET_SRC (set), 1)
1477 && CONST_INT_P (recog_data.operand[2])
1478 && (new_rtx = instantiate_new_reg (recog_data.operand[1], &offset)))
1480 offset += INTVAL (recog_data.operand[2]);
1482 /* If the sum is zero, then replace with a plain move. */
1484 && REG_P (SET_DEST (set))
1485 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1488 emit_move_insn (SET_DEST (set), new_rtx);
1492 emit_insn_before (seq, insn);
1497 x = gen_int_mode (offset, recog_data.operand_mode[2]);
1499 /* Using validate_change and apply_change_group here leaves
1500 recog_data in an invalid state. Since we know exactly what
1501 we want to check, do those two by hand. */
1502 if (safe_insn_predicate (insn_code, 1, new_rtx)
1503 && safe_insn_predicate (insn_code, 2, x))
1505 *recog_data.operand_loc[1] = recog_data.operand[1] = new_rtx;
1506 *recog_data.operand_loc[2] = recog_data.operand[2] = x;
1509 /* Fall through into the regular operand fixup loop in
1510 order to take care of operands other than 1 and 2. */
1516 extract_insn (insn);
1517 insn_code = INSN_CODE (insn);
1520 /* In the general case, we expect virtual registers to appear only in
1521 operands, and then only as either bare registers or inside memories. */
1522 for (i = 0; i < recog_data.n_operands; ++i)
1524 x = recog_data.operand[i];
1525 switch (GET_CODE (x))
1529 rtx addr = XEXP (x, 0);
1530 bool changed = false;
1532 for_each_rtx (&addr, instantiate_virtual_regs_in_rtx, &changed);
1537 x = replace_equiv_address (x, addr);
1538 /* It may happen that the address with the virtual reg
1539 was valid (e.g. based on the virtual stack reg, which might
1540 be acceptable to the predicates with all offsets), whereas
1541 the address now isn't anymore, for instance when the address
1542 is still offsetted, but the base reg isn't virtual-stack-reg
1543 anymore. Below we would do a force_reg on the whole operand,
1544 but this insn might actually only accept memory. Hence,
1545 before doing that last resort, try to reload the address into
1546 a register, so this operand stays a MEM. */
1547 if (!safe_insn_predicate (insn_code, i, x))
1549 addr = force_reg (GET_MODE (addr), addr);
1550 x = replace_equiv_address (x, addr);
1555 emit_insn_before (seq, insn);
1560 new_rtx = instantiate_new_reg (x, &offset);
1561 if (new_rtx == NULL)
1569 /* Careful, special mode predicates may have stuff in
1570 insn_data[insn_code].operand[i].mode that isn't useful
1571 to us for computing a new value. */
1572 /* ??? Recognize address_operand and/or "p" constraints
1573 to see if (plus new offset) is a valid before we put
1574 this through expand_simple_binop. */
1575 x = expand_simple_binop (GET_MODE (x), PLUS, new_rtx,
1576 GEN_INT (offset), NULL_RTX,
1577 1, OPTAB_LIB_WIDEN);
1580 emit_insn_before (seq, insn);
1585 new_rtx = instantiate_new_reg (SUBREG_REG (x), &offset);
1586 if (new_rtx == NULL)
1591 new_rtx = expand_simple_binop (GET_MODE (new_rtx), PLUS, new_rtx,
1592 GEN_INT (offset), NULL_RTX,
1593 1, OPTAB_LIB_WIDEN);
1596 emit_insn_before (seq, insn);
1598 x = simplify_gen_subreg (recog_data.operand_mode[i], new_rtx,
1599 GET_MODE (new_rtx), SUBREG_BYTE (x));
1607 /* At this point, X contains the new value for the operand.
1608 Validate the new value vs the insn predicate. Note that
1609 asm insns will have insn_code -1 here. */
1610 if (!safe_insn_predicate (insn_code, i, x))
1615 gcc_assert (REGNO (x) <= LAST_VIRTUAL_REGISTER);
1616 x = copy_to_reg (x);
1619 x = force_reg (insn_data[insn_code].operand[i].mode, x);
1623 emit_insn_before (seq, insn);
1626 *recog_data.operand_loc[i] = recog_data.operand[i] = x;
1632 /* Propagate operand changes into the duplicates. */
1633 for (i = 0; i < recog_data.n_dups; ++i)
1634 *recog_data.dup_loc[i]
1635 = copy_rtx (recog_data.operand[(unsigned)recog_data.dup_num[i]]);
1637 /* Force re-recognition of the instruction for validation. */
1638 INSN_CODE (insn) = -1;
1641 if (asm_noperands (PATTERN (insn)) >= 0)
1643 if (!check_asm_operands (PATTERN (insn)))
1645 error_for_asm (insn, "impossible constraint in %<asm%>");
1651 if (recog_memoized (insn) < 0)
1652 fatal_insn_not_found (insn);
1656 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1657 do any instantiation required. */
1660 instantiate_decl_rtl (rtx x)
1667 /* If this is a CONCAT, recurse for the pieces. */
1668 if (GET_CODE (x) == CONCAT)
1670 instantiate_decl_rtl (XEXP (x, 0));
1671 instantiate_decl_rtl (XEXP (x, 1));
1675 /* If this is not a MEM, no need to do anything. Similarly if the
1676 address is a constant or a register that is not a virtual register. */
1681 if (CONSTANT_P (addr)
1683 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
1684 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
1687 for_each_rtx (&XEXP (x, 0), instantiate_virtual_regs_in_rtx, NULL);
1690 /* Helper for instantiate_decls called via walk_tree: Process all decls
1691 in the given DECL_VALUE_EXPR. */
1694 instantiate_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
1700 if (DECL_P (t) && DECL_RTL_SET_P (t))
1701 instantiate_decl_rtl (DECL_RTL (t));
1706 /* Subroutine of instantiate_decls: Process all decls in the given
1707 BLOCK node and all its subblocks. */
1710 instantiate_decls_1 (tree let)
1714 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
1716 if (DECL_RTL_SET_P (t))
1717 instantiate_decl_rtl (DECL_RTL (t));
1718 if (TREE_CODE (t) == VAR_DECL && DECL_HAS_VALUE_EXPR_P (t))
1720 tree v = DECL_VALUE_EXPR (t);
1721 walk_tree (&v, instantiate_expr, NULL, NULL);
1725 /* Process all subblocks. */
1726 for (t = BLOCK_SUBBLOCKS (let); t; t = BLOCK_CHAIN (t))
1727 instantiate_decls_1 (t);
1730 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1731 all virtual registers in their DECL_RTL's. */
1734 instantiate_decls (tree fndecl)
1738 /* Process all parameters of the function. */
1739 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
1741 instantiate_decl_rtl (DECL_RTL (decl));
1742 instantiate_decl_rtl (DECL_INCOMING_RTL (decl));
1743 if (DECL_HAS_VALUE_EXPR_P (decl))
1745 tree v = DECL_VALUE_EXPR (decl);
1746 walk_tree (&v, instantiate_expr, NULL, NULL);
1750 /* Now process all variables defined in the function or its subblocks. */
1751 instantiate_decls_1 (DECL_INITIAL (fndecl));
1753 t = cfun->local_decls;
1754 cfun->local_decls = NULL_TREE;
1757 next = TREE_CHAIN (t);
1758 decl = TREE_VALUE (t);
1759 if (DECL_RTL_SET_P (decl))
1760 instantiate_decl_rtl (DECL_RTL (decl));
1765 /* Pass through the INSNS of function FNDECL and convert virtual register
1766 references to hard register references. */
1769 instantiate_virtual_regs (void)
1773 /* Compute the offsets to use for this function. */
1774 in_arg_offset = FIRST_PARM_OFFSET (current_function_decl);
1775 var_offset = STARTING_FRAME_OFFSET;
1776 dynamic_offset = STACK_DYNAMIC_OFFSET (current_function_decl);
1777 out_arg_offset = STACK_POINTER_OFFSET;
1778 #ifdef FRAME_POINTER_CFA_OFFSET
1779 cfa_offset = FRAME_POINTER_CFA_OFFSET (current_function_decl);
1781 cfa_offset = ARG_POINTER_CFA_OFFSET (current_function_decl);
1784 /* Initialize recognition, indicating that volatile is OK. */
1787 /* Scan through all the insns, instantiating every virtual register still
1789 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
1792 /* These patterns in the instruction stream can never be recognized.
1793 Fortunately, they shouldn't contain virtual registers either. */
1794 if (GET_CODE (PATTERN (insn)) == USE
1795 || GET_CODE (PATTERN (insn)) == CLOBBER
1796 || GET_CODE (PATTERN (insn)) == ADDR_VEC
1797 || GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC
1798 || GET_CODE (PATTERN (insn)) == ASM_INPUT)
1800 else if (DEBUG_INSN_P (insn))
1801 for_each_rtx (&INSN_VAR_LOCATION (insn),
1802 instantiate_virtual_regs_in_rtx, NULL);
1804 instantiate_virtual_regs_in_insn (insn);
1806 if (INSN_DELETED_P (insn))
1809 for_each_rtx (®_NOTES (insn), instantiate_virtual_regs_in_rtx, NULL);
1811 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1813 for_each_rtx (&CALL_INSN_FUNCTION_USAGE (insn),
1814 instantiate_virtual_regs_in_rtx, NULL);
1817 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1818 instantiate_decls (current_function_decl);
1820 targetm.instantiate_decls ();
1822 /* Indicate that, from now on, assign_stack_local should use
1823 frame_pointer_rtx. */
1824 virtuals_instantiated = 1;
1828 struct rtl_opt_pass pass_instantiate_virtual_regs =
1834 instantiate_virtual_regs, /* execute */
1837 0, /* static_pass_number */
1838 TV_NONE, /* tv_id */
1839 0, /* properties_required */
1840 0, /* properties_provided */
1841 0, /* properties_destroyed */
1842 0, /* todo_flags_start */
1843 TODO_dump_func /* todo_flags_finish */
1848 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
1849 This means a type for which function calls must pass an address to the
1850 function or get an address back from the function.
1851 EXP may be a type node or an expression (whose type is tested). */
1854 aggregate_value_p (const_tree exp, const_tree fntype)
1856 int i, regno, nregs;
1859 const_tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
1861 /* DECL node associated with FNTYPE when relevant, which we might need to
1862 check for by-invisible-reference returns, typically for CALL_EXPR input
1864 const_tree fndecl = NULL_TREE;
1867 switch (TREE_CODE (fntype))
1870 fndecl = get_callee_fndecl (fntype);
1872 ? TREE_TYPE (fndecl)
1873 : TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (fntype))));
1877 fntype = TREE_TYPE (fndecl);
1882 case IDENTIFIER_NODE:
1886 /* We don't expect other rtl types here. */
1890 if (TREE_CODE (type) == VOID_TYPE)
1893 /* If the front end has decided that this needs to be passed by
1894 reference, do so. */
1895 if ((TREE_CODE (exp) == PARM_DECL || TREE_CODE (exp) == RESULT_DECL)
1896 && DECL_BY_REFERENCE (exp))
1899 /* If the EXPression is a CALL_EXPR, honor DECL_BY_REFERENCE set on the
1900 called function RESULT_DECL, meaning the function returns in memory by
1901 invisible reference. This check lets front-ends not set TREE_ADDRESSABLE
1902 on the function type, which used to be the way to request such a return
1903 mechanism but might now be causing troubles at gimplification time if
1904 temporaries with the function type need to be created. */
1905 if (TREE_CODE (exp) == CALL_EXPR && fndecl && DECL_RESULT (fndecl)
1906 && DECL_BY_REFERENCE (DECL_RESULT (fndecl)))
1909 if (targetm.calls.return_in_memory (type, fntype))
1911 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
1912 and thus can't be returned in registers. */
1913 if (TREE_ADDRESSABLE (type))
1915 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
1917 /* Make sure we have suitable call-clobbered regs to return
1918 the value in; if not, we must return it in memory. */
1919 reg = hard_function_value (type, 0, fntype, 0);
1921 /* If we have something other than a REG (e.g. a PARALLEL), then assume
1926 regno = REGNO (reg);
1927 nregs = hard_regno_nregs[regno][TYPE_MODE (type)];
1928 for (i = 0; i < nregs; i++)
1929 if (! call_used_regs[regno + i])
1934 /* Return true if we should assign DECL a pseudo register; false if it
1935 should live on the local stack. */
1938 use_register_for_decl (const_tree decl)
1940 if (!targetm.calls.allocate_stack_slots_for_args())
1943 /* Honor volatile. */
1944 if (TREE_SIDE_EFFECTS (decl))
1947 /* Honor addressability. */
1948 if (TREE_ADDRESSABLE (decl))
1951 /* Only register-like things go in registers. */
1952 if (DECL_MODE (decl) == BLKmode)
1955 /* If -ffloat-store specified, don't put explicit float variables
1957 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
1958 propagates values across these stores, and it probably shouldn't. */
1959 if (flag_float_store && FLOAT_TYPE_P (TREE_TYPE (decl)))
1962 /* If we're not interested in tracking debugging information for
1963 this decl, then we can certainly put it in a register. */
1964 if (DECL_IGNORED_P (decl))
1970 if (!DECL_REGISTER (decl))
1973 switch (TREE_CODE (TREE_TYPE (decl)))
1977 case QUAL_UNION_TYPE:
1978 /* When not optimizing, disregard register keyword for variables with
1979 types containing methods, otherwise the methods won't be callable
1980 from the debugger. */
1981 if (TYPE_METHODS (TREE_TYPE (decl)))
1991 /* Return true if TYPE should be passed by invisible reference. */
1994 pass_by_reference (CUMULATIVE_ARGS *ca, enum machine_mode mode,
1995 tree type, bool named_arg)
1999 /* If this type contains non-trivial constructors, then it is
2000 forbidden for the middle-end to create any new copies. */
2001 if (TREE_ADDRESSABLE (type))
2004 /* GCC post 3.4 passes *all* variable sized types by reference. */
2005 if (!TYPE_SIZE (type) || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
2009 return targetm.calls.pass_by_reference (ca, mode, type, named_arg);
2012 /* Return true if TYPE, which is passed by reference, should be callee
2013 copied instead of caller copied. */
2016 reference_callee_copied (CUMULATIVE_ARGS *ca, enum machine_mode mode,
2017 tree type, bool named_arg)
2019 if (type && TREE_ADDRESSABLE (type))
2021 return targetm.calls.callee_copies (ca, mode, type, named_arg);
2024 /* Structures to communicate between the subroutines of assign_parms.
2025 The first holds data persistent across all parameters, the second
2026 is cleared out for each parameter. */
2028 struct assign_parm_data_all
2030 CUMULATIVE_ARGS args_so_far;
2031 struct args_size stack_args_size;
2032 tree function_result_decl;
2034 rtx first_conversion_insn;
2035 rtx last_conversion_insn;
2036 HOST_WIDE_INT pretend_args_size;
2037 HOST_WIDE_INT extra_pretend_bytes;
2038 int reg_parm_stack_space;
2041 struct assign_parm_data_one
2047 enum machine_mode nominal_mode;
2048 enum machine_mode passed_mode;
2049 enum machine_mode promoted_mode;
2050 struct locate_and_pad_arg_data locate;
2052 BOOL_BITFIELD named_arg : 1;
2053 BOOL_BITFIELD passed_pointer : 1;
2054 BOOL_BITFIELD on_stack : 1;
2055 BOOL_BITFIELD loaded_in_reg : 1;
2058 /* A subroutine of assign_parms. Initialize ALL. */
2061 assign_parms_initialize_all (struct assign_parm_data_all *all)
2065 memset (all, 0, sizeof (*all));
2067 fntype = TREE_TYPE (current_function_decl);
2069 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
2070 INIT_CUMULATIVE_INCOMING_ARGS (all->args_so_far, fntype, NULL_RTX);
2072 INIT_CUMULATIVE_ARGS (all->args_so_far, fntype, NULL_RTX,
2073 current_function_decl, -1);
2076 #ifdef REG_PARM_STACK_SPACE
2077 all->reg_parm_stack_space = REG_PARM_STACK_SPACE (current_function_decl);
2081 /* If ARGS contains entries with complex types, split the entry into two
2082 entries of the component type. Return a new list of substitutions are
2083 needed, else the old list. */
2086 split_complex_args (VEC(tree, heap) **args)
2091 for (i = 0; VEC_iterate (tree, *args, i, p); ++i)
2093 tree type = TREE_TYPE (p);
2094 if (TREE_CODE (type) == COMPLEX_TYPE
2095 && targetm.calls.split_complex_arg (type))
2098 tree subtype = TREE_TYPE (type);
2099 bool addressable = TREE_ADDRESSABLE (p);
2101 /* Rewrite the PARM_DECL's type with its component. */
2103 TREE_TYPE (p) = subtype;
2104 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
2105 DECL_MODE (p) = VOIDmode;
2106 DECL_SIZE (p) = NULL;
2107 DECL_SIZE_UNIT (p) = NULL;
2108 /* If this arg must go in memory, put it in a pseudo here.
2109 We can't allow it to go in memory as per normal parms,
2110 because the usual place might not have the imag part
2111 adjacent to the real part. */
2112 DECL_ARTIFICIAL (p) = addressable;
2113 DECL_IGNORED_P (p) = addressable;
2114 TREE_ADDRESSABLE (p) = 0;
2116 VEC_replace (tree, *args, i, p);
2118 /* Build a second synthetic decl. */
2119 decl = build_decl (EXPR_LOCATION (p),
2120 PARM_DECL, NULL_TREE, subtype);
2121 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
2122 DECL_ARTIFICIAL (decl) = addressable;
2123 DECL_IGNORED_P (decl) = addressable;
2124 layout_decl (decl, 0);
2125 VEC_safe_insert (tree, heap, *args, ++i, decl);
2130 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
2131 the hidden struct return argument, and (abi willing) complex args.
2132 Return the new parameter list. */
2134 static VEC(tree, heap) *
2135 assign_parms_augmented_arg_list (struct assign_parm_data_all *all)
2137 tree fndecl = current_function_decl;
2138 tree fntype = TREE_TYPE (fndecl);
2139 VEC(tree, heap) *fnargs = NULL;
2142 for (arg = DECL_ARGUMENTS (fndecl); arg; arg = TREE_CHAIN (arg))
2143 VEC_safe_push (tree, heap, fnargs, arg);
2145 all->orig_fnargs = DECL_ARGUMENTS (fndecl);
2147 /* If struct value address is treated as the first argument, make it so. */
2148 if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
2149 && ! cfun->returns_pcc_struct
2150 && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
2152 tree type = build_pointer_type (TREE_TYPE (fntype));
2155 decl = build_decl (DECL_SOURCE_LOCATION (fndecl),
2156 PARM_DECL, NULL_TREE, type);
2157 DECL_ARG_TYPE (decl) = type;
2158 DECL_ARTIFICIAL (decl) = 1;
2159 DECL_IGNORED_P (decl) = 1;
2161 TREE_CHAIN (decl) = all->orig_fnargs;
2162 all->orig_fnargs = decl;
2163 VEC_safe_insert (tree, heap, fnargs, 0, decl);
2165 all->function_result_decl = decl;
2168 /* If the target wants to split complex arguments into scalars, do so. */
2169 if (targetm.calls.split_complex_arg)
2170 split_complex_args (&fnargs);
2175 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2176 data for the parameter. Incorporate ABI specifics such as pass-by-
2177 reference and type promotion. */
2180 assign_parm_find_data_types (struct assign_parm_data_all *all, tree parm,
2181 struct assign_parm_data_one *data)
2183 tree nominal_type, passed_type;
2184 enum machine_mode nominal_mode, passed_mode, promoted_mode;
2187 memset (data, 0, sizeof (*data));
2189 /* NAMED_ARG is a misnomer. We really mean 'non-variadic'. */
2191 data->named_arg = 1; /* No variadic parms. */
2192 else if (TREE_CHAIN (parm))
2193 data->named_arg = 1; /* Not the last non-variadic parm. */
2194 else if (targetm.calls.strict_argument_naming (&all->args_so_far))
2195 data->named_arg = 1; /* Only variadic ones are unnamed. */
2197 data->named_arg = 0; /* Treat as variadic. */
2199 nominal_type = TREE_TYPE (parm);
2200 passed_type = DECL_ARG_TYPE (parm);
2202 /* Look out for errors propagating this far. Also, if the parameter's
2203 type is void then its value doesn't matter. */
2204 if (TREE_TYPE (parm) == error_mark_node
2205 /* This can happen after weird syntax errors
2206 or if an enum type is defined among the parms. */
2207 || TREE_CODE (parm) != PARM_DECL
2208 || passed_type == NULL
2209 || VOID_TYPE_P (nominal_type))
2211 nominal_type = passed_type = void_type_node;
2212 nominal_mode = passed_mode = promoted_mode = VOIDmode;
2216 /* Find mode of arg as it is passed, and mode of arg as it should be
2217 during execution of this function. */
2218 passed_mode = TYPE_MODE (passed_type);
2219 nominal_mode = TYPE_MODE (nominal_type);
2221 /* If the parm is to be passed as a transparent union, use the type of
2222 the first field for the tests below. We have already verified that
2223 the modes are the same. */
2224 if (TREE_CODE (passed_type) == UNION_TYPE
2225 && TYPE_TRANSPARENT_UNION (passed_type))
2226 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
2228 /* See if this arg was passed by invisible reference. */
2229 if (pass_by_reference (&all->args_so_far, passed_mode,
2230 passed_type, data->named_arg))
2232 passed_type = nominal_type = build_pointer_type (passed_type);
2233 data->passed_pointer = true;
2234 passed_mode = nominal_mode = Pmode;
2237 /* Find mode as it is passed by the ABI. */
2238 unsignedp = TYPE_UNSIGNED (passed_type);
2239 promoted_mode = promote_function_mode (passed_type, passed_mode, &unsignedp,
2240 TREE_TYPE (current_function_decl), 0);
2243 data->nominal_type = nominal_type;
2244 data->passed_type = passed_type;
2245 data->nominal_mode = nominal_mode;
2246 data->passed_mode = passed_mode;
2247 data->promoted_mode = promoted_mode;
2250 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2253 assign_parms_setup_varargs (struct assign_parm_data_all *all,
2254 struct assign_parm_data_one *data, bool no_rtl)
2256 int varargs_pretend_bytes = 0;
2258 targetm.calls.setup_incoming_varargs (&all->args_so_far,
2259 data->promoted_mode,
2261 &varargs_pretend_bytes, no_rtl);
2263 /* If the back-end has requested extra stack space, record how much is
2264 needed. Do not change pretend_args_size otherwise since it may be
2265 nonzero from an earlier partial argument. */
2266 if (varargs_pretend_bytes > 0)
2267 all->pretend_args_size = varargs_pretend_bytes;
2270 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2271 the incoming location of the current parameter. */
2274 assign_parm_find_entry_rtl (struct assign_parm_data_all *all,
2275 struct assign_parm_data_one *data)
2277 HOST_WIDE_INT pretend_bytes = 0;
2281 if (data->promoted_mode == VOIDmode)
2283 data->entry_parm = data->stack_parm = const0_rtx;
2287 #ifdef FUNCTION_INCOMING_ARG
2288 entry_parm = FUNCTION_INCOMING_ARG (all->args_so_far, data->promoted_mode,
2289 data->passed_type, data->named_arg);
2291 entry_parm = FUNCTION_ARG (all->args_so_far, data->promoted_mode,
2292 data->passed_type, data->named_arg);
2295 if (entry_parm == 0)
2296 data->promoted_mode = data->passed_mode;
2298 /* Determine parm's home in the stack, in case it arrives in the stack
2299 or we should pretend it did. Compute the stack position and rtx where
2300 the argument arrives and its size.
2302 There is one complexity here: If this was a parameter that would
2303 have been passed in registers, but wasn't only because it is
2304 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2305 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2306 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2307 as it was the previous time. */
2308 in_regs = entry_parm != 0;
2309 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2312 if (!in_regs && !data->named_arg)
2314 if (targetm.calls.pretend_outgoing_varargs_named (&all->args_so_far))
2317 #ifdef FUNCTION_INCOMING_ARG
2318 tem = FUNCTION_INCOMING_ARG (all->args_so_far, data->promoted_mode,
2319 data->passed_type, true);
2321 tem = FUNCTION_ARG (all->args_so_far, data->promoted_mode,
2322 data->passed_type, true);
2324 in_regs = tem != NULL;
2328 /* If this parameter was passed both in registers and in the stack, use
2329 the copy on the stack. */
2330 if (targetm.calls.must_pass_in_stack (data->promoted_mode,
2338 partial = targetm.calls.arg_partial_bytes (&all->args_so_far,
2339 data->promoted_mode,
2342 data->partial = partial;
2344 /* The caller might already have allocated stack space for the
2345 register parameters. */
2346 if (partial != 0 && all->reg_parm_stack_space == 0)
2348 /* Part of this argument is passed in registers and part
2349 is passed on the stack. Ask the prologue code to extend
2350 the stack part so that we can recreate the full value.
2352 PRETEND_BYTES is the size of the registers we need to store.
2353 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2354 stack space that the prologue should allocate.
2356 Internally, gcc assumes that the argument pointer is aligned
2357 to STACK_BOUNDARY bits. This is used both for alignment
2358 optimizations (see init_emit) and to locate arguments that are
2359 aligned to more than PARM_BOUNDARY bits. We must preserve this
2360 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2361 a stack boundary. */
2363 /* We assume at most one partial arg, and it must be the first
2364 argument on the stack. */
2365 gcc_assert (!all->extra_pretend_bytes && !all->pretend_args_size);
2367 pretend_bytes = partial;
2368 all->pretend_args_size = CEIL_ROUND (pretend_bytes, STACK_BYTES);
2370 /* We want to align relative to the actual stack pointer, so
2371 don't include this in the stack size until later. */
2372 all->extra_pretend_bytes = all->pretend_args_size;
2376 locate_and_pad_parm (data->promoted_mode, data->passed_type, in_regs,
2377 entry_parm ? data->partial : 0, current_function_decl,
2378 &all->stack_args_size, &data->locate);
2380 /* Update parm_stack_boundary if this parameter is passed in the
2382 if (!in_regs && crtl->parm_stack_boundary < data->locate.boundary)
2383 crtl->parm_stack_boundary = data->locate.boundary;
2385 /* Adjust offsets to include the pretend args. */
2386 pretend_bytes = all->extra_pretend_bytes - pretend_bytes;
2387 data->locate.slot_offset.constant += pretend_bytes;
2388 data->locate.offset.constant += pretend_bytes;
2390 data->entry_parm = entry_parm;
2393 /* A subroutine of assign_parms. If there is actually space on the stack
2394 for this parm, count it in stack_args_size and return true. */
2397 assign_parm_is_stack_parm (struct assign_parm_data_all *all,
2398 struct assign_parm_data_one *data)
2400 /* Trivially true if we've no incoming register. */
2401 if (data->entry_parm == NULL)
2403 /* Also true if we're partially in registers and partially not,
2404 since we've arranged to drop the entire argument on the stack. */
2405 else if (data->partial != 0)
2407 /* Also true if the target says that it's passed in both registers
2408 and on the stack. */
2409 else if (GET_CODE (data->entry_parm) == PARALLEL
2410 && XEXP (XVECEXP (data->entry_parm, 0, 0), 0) == NULL_RTX)
2412 /* Also true if the target says that there's stack allocated for
2413 all register parameters. */
2414 else if (all->reg_parm_stack_space > 0)
2416 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2420 all->stack_args_size.constant += data->locate.size.constant;
2421 if (data->locate.size.var)
2422 ADD_PARM_SIZE (all->stack_args_size, data->locate.size.var);
2427 /* A subroutine of assign_parms. Given that this parameter is allocated
2428 stack space by the ABI, find it. */
2431 assign_parm_find_stack_rtl (tree parm, struct assign_parm_data_one *data)
2433 rtx offset_rtx, stack_parm;
2434 unsigned int align, boundary;
2436 /* If we're passing this arg using a reg, make its stack home the
2437 aligned stack slot. */
2438 if (data->entry_parm)
2439 offset_rtx = ARGS_SIZE_RTX (data->locate.slot_offset);
2441 offset_rtx = ARGS_SIZE_RTX (data->locate.offset);
2443 stack_parm = crtl->args.internal_arg_pointer;
2444 if (offset_rtx != const0_rtx)
2445 stack_parm = gen_rtx_PLUS (Pmode, stack_parm, offset_rtx);
2446 stack_parm = gen_rtx_MEM (data->promoted_mode, stack_parm);
2448 if (!data->passed_pointer)
2450 set_mem_attributes (stack_parm, parm, 1);
2451 /* set_mem_attributes could set MEM_SIZE to the passed mode's size,
2452 while promoted mode's size is needed. */
2453 if (data->promoted_mode != BLKmode
2454 && data->promoted_mode != DECL_MODE (parm))
2456 set_mem_size (stack_parm,
2457 GEN_INT (GET_MODE_SIZE (data->promoted_mode)));
2458 if (MEM_EXPR (stack_parm) && MEM_OFFSET (stack_parm))
2460 int offset = subreg_lowpart_offset (DECL_MODE (parm),
2461 data->promoted_mode);
2463 set_mem_offset (stack_parm,
2464 plus_constant (MEM_OFFSET (stack_parm),
2470 boundary = data->locate.boundary;
2471 align = BITS_PER_UNIT;
2473 /* If we're padding upward, we know that the alignment of the slot
2474 is FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2475 intentionally forcing upward padding. Otherwise we have to come
2476 up with a guess at the alignment based on OFFSET_RTX. */
2477 if (data->locate.where_pad != downward || data->entry_parm)
2479 else if (CONST_INT_P (offset_rtx))
2481 align = INTVAL (offset_rtx) * BITS_PER_UNIT | boundary;
2482 align = align & -align;
2484 set_mem_align (stack_parm, align);
2486 if (data->entry_parm)
2487 set_reg_attrs_for_parm (data->entry_parm, stack_parm);
2489 data->stack_parm = stack_parm;
2492 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2493 always valid and contiguous. */
2496 assign_parm_adjust_entry_rtl (struct assign_parm_data_one *data)
2498 rtx entry_parm = data->entry_parm;
2499 rtx stack_parm = data->stack_parm;
2501 /* If this parm was passed part in regs and part in memory, pretend it
2502 arrived entirely in memory by pushing the register-part onto the stack.
2503 In the special case of a DImode or DFmode that is split, we could put
2504 it together in a pseudoreg directly, but for now that's not worth
2506 if (data->partial != 0)
2508 /* Handle calls that pass values in multiple non-contiguous
2509 locations. The Irix 6 ABI has examples of this. */
2510 if (GET_CODE (entry_parm) == PARALLEL)
2511 emit_group_store (validize_mem (stack_parm), entry_parm,
2513 int_size_in_bytes (data->passed_type));
2516 gcc_assert (data->partial % UNITS_PER_WORD == 0);
2517 move_block_from_reg (REGNO (entry_parm), validize_mem (stack_parm),
2518 data->partial / UNITS_PER_WORD);
2521 entry_parm = stack_parm;
2524 /* If we didn't decide this parm came in a register, by default it came
2526 else if (entry_parm == NULL)
2527 entry_parm = stack_parm;
2529 /* When an argument is passed in multiple locations, we can't make use
2530 of this information, but we can save some copying if the whole argument
2531 is passed in a single register. */
2532 else if (GET_CODE (entry_parm) == PARALLEL
2533 && data->nominal_mode != BLKmode
2534 && data->passed_mode != BLKmode)
2536 size_t i, len = XVECLEN (entry_parm, 0);
2538 for (i = 0; i < len; i++)
2539 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
2540 && REG_P (XEXP (XVECEXP (entry_parm, 0, i), 0))
2541 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
2542 == data->passed_mode)
2543 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
2545 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
2550 data->entry_parm = entry_parm;
2553 /* A subroutine of assign_parms. Reconstitute any values which were
2554 passed in multiple registers and would fit in a single register. */
2557 assign_parm_remove_parallels (struct assign_parm_data_one *data)
2559 rtx entry_parm = data->entry_parm;
2561 /* Convert the PARALLEL to a REG of the same mode as the parallel.
2562 This can be done with register operations rather than on the
2563 stack, even if we will store the reconstituted parameter on the
2565 if (GET_CODE (entry_parm) == PARALLEL && GET_MODE (entry_parm) != BLKmode)
2567 rtx parmreg = gen_reg_rtx (GET_MODE (entry_parm));
2568 emit_group_store (parmreg, entry_parm, data->passed_type,
2569 GET_MODE_SIZE (GET_MODE (entry_parm)));
2570 entry_parm = parmreg;
2573 data->entry_parm = entry_parm;
2576 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2577 always valid and properly aligned. */
2580 assign_parm_adjust_stack_rtl (struct assign_parm_data_one *data)
2582 rtx stack_parm = data->stack_parm;
2584 /* If we can't trust the parm stack slot to be aligned enough for its
2585 ultimate type, don't use that slot after entry. We'll make another
2586 stack slot, if we need one. */
2588 && ((STRICT_ALIGNMENT
2589 && GET_MODE_ALIGNMENT (data->nominal_mode) > MEM_ALIGN (stack_parm))
2590 || (data->nominal_type
2591 && TYPE_ALIGN (data->nominal_type) > MEM_ALIGN (stack_parm)
2592 && MEM_ALIGN (stack_parm) < PREFERRED_STACK_BOUNDARY)))
2595 /* If parm was passed in memory, and we need to convert it on entry,
2596 don't store it back in that same slot. */
2597 else if (data->entry_parm == stack_parm
2598 && data->nominal_mode != BLKmode
2599 && data->nominal_mode != data->passed_mode)
2602 /* If stack protection is in effect for this function, don't leave any
2603 pointers in their passed stack slots. */
2604 else if (crtl->stack_protect_guard
2605 && (flag_stack_protect == 2
2606 || data->passed_pointer
2607 || POINTER_TYPE_P (data->nominal_type)))
2610 data->stack_parm = stack_parm;
2613 /* A subroutine of assign_parms. Return true if the current parameter
2614 should be stored as a BLKmode in the current frame. */
2617 assign_parm_setup_block_p (struct assign_parm_data_one *data)
2619 if (data->nominal_mode == BLKmode)
2621 if (GET_MODE (data->entry_parm) == BLKmode)
2624 #ifdef BLOCK_REG_PADDING
2625 /* Only assign_parm_setup_block knows how to deal with register arguments
2626 that are padded at the least significant end. */
2627 if (REG_P (data->entry_parm)
2628 && GET_MODE_SIZE (data->promoted_mode) < UNITS_PER_WORD
2629 && (BLOCK_REG_PADDING (data->passed_mode, data->passed_type, 1)
2630 == (BYTES_BIG_ENDIAN ? upward : downward)))
2637 /* A subroutine of assign_parms. Arrange for the parameter to be
2638 present and valid in DATA->STACK_RTL. */
2641 assign_parm_setup_block (struct assign_parm_data_all *all,
2642 tree parm, struct assign_parm_data_one *data)
2644 rtx entry_parm = data->entry_parm;
2645 rtx stack_parm = data->stack_parm;
2647 HOST_WIDE_INT size_stored;
2649 if (GET_CODE (entry_parm) == PARALLEL)
2650 entry_parm = emit_group_move_into_temps (entry_parm);
2652 size = int_size_in_bytes (data->passed_type);
2653 size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
2654 if (stack_parm == 0)
2656 DECL_ALIGN (parm) = MAX (DECL_ALIGN (parm), BITS_PER_WORD);
2657 stack_parm = assign_stack_local (BLKmode, size_stored,
2659 if (GET_MODE_SIZE (GET_MODE (entry_parm)) == size)
2660 PUT_MODE (stack_parm, GET_MODE (entry_parm));
2661 set_mem_attributes (stack_parm, parm, 1);
2664 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2665 calls that pass values in multiple non-contiguous locations. */
2666 if (REG_P (entry_parm) || GET_CODE (entry_parm) == PARALLEL)
2670 /* Note that we will be storing an integral number of words.
2671 So we have to be careful to ensure that we allocate an
2672 integral number of words. We do this above when we call
2673 assign_stack_local if space was not allocated in the argument
2674 list. If it was, this will not work if PARM_BOUNDARY is not
2675 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2676 if it becomes a problem. Exception is when BLKmode arrives
2677 with arguments not conforming to word_mode. */
2679 if (data->stack_parm == 0)
2681 else if (GET_CODE (entry_parm) == PARALLEL)
2684 gcc_assert (!size || !(PARM_BOUNDARY % BITS_PER_WORD));
2686 mem = validize_mem (stack_parm);
2688 /* Handle values in multiple non-contiguous locations. */
2689 if (GET_CODE (entry_parm) == PARALLEL)
2691 push_to_sequence2 (all->first_conversion_insn,
2692 all->last_conversion_insn);
2693 emit_group_store (mem, entry_parm, data->passed_type, size);
2694 all->first_conversion_insn = get_insns ();
2695 all->last_conversion_insn = get_last_insn ();
2702 /* If SIZE is that of a mode no bigger than a word, just use
2703 that mode's store operation. */
2704 else if (size <= UNITS_PER_WORD)
2706 enum machine_mode mode
2707 = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
2710 #ifdef BLOCK_REG_PADDING
2711 && (size == UNITS_PER_WORD
2712 || (BLOCK_REG_PADDING (mode, data->passed_type, 1)
2713 != (BYTES_BIG_ENDIAN ? upward : downward)))
2719 /* We are really truncating a word_mode value containing
2720 SIZE bytes into a value of mode MODE. If such an
2721 operation requires no actual instructions, we can refer
2722 to the value directly in mode MODE, otherwise we must
2723 start with the register in word_mode and explicitly
2725 if (TRULY_NOOP_TRUNCATION (size * BITS_PER_UNIT, BITS_PER_WORD))
2726 reg = gen_rtx_REG (mode, REGNO (entry_parm));
2729 reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
2730 reg = convert_to_mode (mode, copy_to_reg (reg), 1);
2732 emit_move_insn (change_address (mem, mode, 0), reg);
2735 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
2736 machine must be aligned to the left before storing
2737 to memory. Note that the previous test doesn't
2738 handle all cases (e.g. SIZE == 3). */
2739 else if (size != UNITS_PER_WORD
2740 #ifdef BLOCK_REG_PADDING
2741 && (BLOCK_REG_PADDING (mode, data->passed_type, 1)
2749 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2750 rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
2752 x = expand_shift (LSHIFT_EXPR, word_mode, reg,
2753 build_int_cst (NULL_TREE, by),
2755 tem = change_address (mem, word_mode, 0);
2756 emit_move_insn (tem, x);
2759 move_block_from_reg (REGNO (entry_parm), mem,
2760 size_stored / UNITS_PER_WORD);
2763 move_block_from_reg (REGNO (entry_parm), mem,
2764 size_stored / UNITS_PER_WORD);
2766 else if (data->stack_parm == 0)
2768 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
2769 emit_block_move (stack_parm, data->entry_parm, GEN_INT (size),
2771 all->first_conversion_insn = get_insns ();
2772 all->last_conversion_insn = get_last_insn ();
2776 data->stack_parm = stack_parm;
2777 SET_DECL_RTL (parm, stack_parm);
2780 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
2781 parameter. Get it there. Perform all ABI specified conversions. */
2784 assign_parm_setup_reg (struct assign_parm_data_all *all, tree parm,
2785 struct assign_parm_data_one *data)
2788 enum machine_mode promoted_nominal_mode;
2789 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (parm));
2790 bool did_conversion = false;
2792 /* Store the parm in a pseudoregister during the function, but we may
2793 need to do it in a wider mode. Using 2 here makes the result
2794 consistent with promote_decl_mode and thus expand_expr_real_1. */
2795 promoted_nominal_mode
2796 = promote_function_mode (data->nominal_type, data->nominal_mode, &unsignedp,
2797 TREE_TYPE (current_function_decl), 2);
2799 parmreg = gen_reg_rtx (promoted_nominal_mode);
2801 if (!DECL_ARTIFICIAL (parm))
2802 mark_user_reg (parmreg);
2804 /* If this was an item that we received a pointer to,
2805 set DECL_RTL appropriately. */
2806 if (data->passed_pointer)
2808 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data->passed_type)), parmreg);
2809 set_mem_attributes (x, parm, 1);
2810 SET_DECL_RTL (parm, x);
2813 SET_DECL_RTL (parm, parmreg);
2815 assign_parm_remove_parallels (data);
2817 /* Copy the value into the register, thus bridging between
2818 assign_parm_find_data_types and expand_expr_real_1. */
2819 if (data->nominal_mode != data->passed_mode
2820 || promoted_nominal_mode != data->promoted_mode)
2824 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
2825 mode, by the caller. We now have to convert it to
2826 NOMINAL_MODE, if different. However, PARMREG may be in
2827 a different mode than NOMINAL_MODE if it is being stored
2830 If ENTRY_PARM is a hard register, it might be in a register
2831 not valid for operating in its mode (e.g., an odd-numbered
2832 register for a DFmode). In that case, moves are the only
2833 thing valid, so we can't do a convert from there. This
2834 occurs when the calling sequence allow such misaligned
2837 In addition, the conversion may involve a call, which could
2838 clobber parameters which haven't been copied to pseudo
2839 registers yet. Therefore, we must first copy the parm to
2840 a pseudo reg here, and save the conversion until after all
2841 parameters have been moved. */
2843 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
2845 emit_move_insn (tempreg, validize_mem (data->entry_parm));
2847 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
2848 tempreg = convert_to_mode (data->nominal_mode, tempreg, unsignedp);
2850 if (GET_CODE (tempreg) == SUBREG
2851 && GET_MODE (tempreg) == data->nominal_mode
2852 && REG_P (SUBREG_REG (tempreg))
2853 && data->nominal_mode == data->passed_mode
2854 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (data->entry_parm)
2855 && GET_MODE_SIZE (GET_MODE (tempreg))
2856 < GET_MODE_SIZE (GET_MODE (data->entry_parm)))
2858 /* The argument is already sign/zero extended, so note it
2860 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
2861 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
2864 /* TREE_USED gets set erroneously during expand_assignment. */
2865 save_tree_used = TREE_USED (parm);
2866 expand_assignment (parm, make_tree (data->nominal_type, tempreg), false);
2867 TREE_USED (parm) = save_tree_used;
2868 all->first_conversion_insn = get_insns ();
2869 all->last_conversion_insn = get_last_insn ();
2872 did_conversion = true;
2875 emit_move_insn (parmreg, validize_mem (data->entry_parm));
2877 /* If we were passed a pointer but the actual value can safely live
2878 in a register, put it in one. */
2879 if (data->passed_pointer
2880 && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
2881 /* If by-reference argument was promoted, demote it. */
2882 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
2883 || use_register_for_decl (parm)))
2885 /* We can't use nominal_mode, because it will have been set to
2886 Pmode above. We must use the actual mode of the parm. */
2887 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
2888 mark_user_reg (parmreg);
2890 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
2892 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
2893 int unsigned_p = TYPE_UNSIGNED (TREE_TYPE (parm));
2895 push_to_sequence2 (all->first_conversion_insn,
2896 all->last_conversion_insn);
2897 emit_move_insn (tempreg, DECL_RTL (parm));
2898 tempreg = convert_to_mode (GET_MODE (parmreg), tempreg, unsigned_p);
2899 emit_move_insn (parmreg, tempreg);
2900 all->first_conversion_insn = get_insns ();
2901 all->last_conversion_insn = get_last_insn ();
2904 did_conversion = true;
2907 emit_move_insn (parmreg, DECL_RTL (parm));
2909 SET_DECL_RTL (parm, parmreg);
2911 /* STACK_PARM is the pointer, not the parm, and PARMREG is
2913 data->stack_parm = NULL;
2916 /* Mark the register as eliminable if we did no conversion and it was
2917 copied from memory at a fixed offset, and the arg pointer was not
2918 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
2919 offset formed an invalid address, such memory-equivalences as we
2920 make here would screw up life analysis for it. */
2921 if (data->nominal_mode == data->passed_mode
2923 && data->stack_parm != 0
2924 && MEM_P (data->stack_parm)
2925 && data->locate.offset.var == 0
2926 && reg_mentioned_p (virtual_incoming_args_rtx,
2927 XEXP (data->stack_parm, 0)))
2929 rtx linsn = get_last_insn ();
2932 /* Mark complex types separately. */
2933 if (GET_CODE (parmreg) == CONCAT)
2935 enum machine_mode submode
2936 = GET_MODE_INNER (GET_MODE (parmreg));
2937 int regnor = REGNO (XEXP (parmreg, 0));
2938 int regnoi = REGNO (XEXP (parmreg, 1));
2939 rtx stackr = adjust_address_nv (data->stack_parm, submode, 0);
2940 rtx stacki = adjust_address_nv (data->stack_parm, submode,
2941 GET_MODE_SIZE (submode));
2943 /* Scan backwards for the set of the real and
2945 for (sinsn = linsn; sinsn != 0;
2946 sinsn = prev_nonnote_insn (sinsn))
2948 set = single_set (sinsn);
2952 if (SET_DEST (set) == regno_reg_rtx [regnoi])
2953 set_unique_reg_note (sinsn, REG_EQUIV, stacki);
2954 else if (SET_DEST (set) == regno_reg_rtx [regnor])
2955 set_unique_reg_note (sinsn, REG_EQUIV, stackr);
2958 else if ((set = single_set (linsn)) != 0
2959 && SET_DEST (set) == parmreg)
2960 set_unique_reg_note (linsn, REG_EQUIV, data->stack_parm);
2963 /* For pointer data type, suggest pointer register. */
2964 if (POINTER_TYPE_P (TREE_TYPE (parm)))
2965 mark_reg_pointer (parmreg,
2966 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
2969 /* A subroutine of assign_parms. Allocate stack space to hold the current
2970 parameter. Get it there. Perform all ABI specified conversions. */
2973 assign_parm_setup_stack (struct assign_parm_data_all *all, tree parm,
2974 struct assign_parm_data_one *data)
2976 /* Value must be stored in the stack slot STACK_PARM during function
2978 bool to_conversion = false;
2980 assign_parm_remove_parallels (data);
2982 if (data->promoted_mode != data->nominal_mode)
2984 /* Conversion is required. */
2985 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
2987 emit_move_insn (tempreg, validize_mem (data->entry_parm));
2989 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
2990 to_conversion = true;
2992 data->entry_parm = convert_to_mode (data->nominal_mode, tempreg,
2993 TYPE_UNSIGNED (TREE_TYPE (parm)));
2995 if (data->stack_parm)
2997 int offset = subreg_lowpart_offset (data->nominal_mode,
2998 GET_MODE (data->stack_parm));
2999 /* ??? This may need a big-endian conversion on sparc64. */
3001 = adjust_address (data->stack_parm, data->nominal_mode, 0);
3002 if (offset && MEM_OFFSET (data->stack_parm))
3003 set_mem_offset (data->stack_parm,
3004 plus_constant (MEM_OFFSET (data->stack_parm),
3009 if (data->entry_parm != data->stack_parm)
3013 if (data->stack_parm == 0)
3015 int align = STACK_SLOT_ALIGNMENT (data->passed_type,
3016 GET_MODE (data->entry_parm),
3017 TYPE_ALIGN (data->passed_type));
3019 = assign_stack_local (GET_MODE (data->entry_parm),
3020 GET_MODE_SIZE (GET_MODE (data->entry_parm)),
3022 set_mem_attributes (data->stack_parm, parm, 1);
3025 dest = validize_mem (data->stack_parm);
3026 src = validize_mem (data->entry_parm);
3030 /* Use a block move to handle potentially misaligned entry_parm. */
3032 push_to_sequence2 (all->first_conversion_insn,
3033 all->last_conversion_insn);
3034 to_conversion = true;
3036 emit_block_move (dest, src,
3037 GEN_INT (int_size_in_bytes (data->passed_type)),
3041 emit_move_insn (dest, src);
3046 all->first_conversion_insn = get_insns ();
3047 all->last_conversion_insn = get_last_insn ();
3051 SET_DECL_RTL (parm, data->stack_parm);
3054 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
3055 undo the frobbing that we did in assign_parms_augmented_arg_list. */
3058 assign_parms_unsplit_complex (struct assign_parm_data_all *all,
3059 VEC(tree, heap) *fnargs)
3062 tree orig_fnargs = all->orig_fnargs;
3065 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm), ++i)
3067 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE
3068 && targetm.calls.split_complex_arg (TREE_TYPE (parm)))
3070 rtx tmp, real, imag;
3071 enum machine_mode inner = GET_MODE_INNER (DECL_MODE (parm));
3073 real = DECL_RTL (VEC_index (tree, fnargs, i));
3074 imag = DECL_RTL (VEC_index (tree, fnargs, i + 1));
3075 if (inner != GET_MODE (real))
3077 real = gen_lowpart_SUBREG (inner, real);
3078 imag = gen_lowpart_SUBREG (inner, imag);
3081 if (TREE_ADDRESSABLE (parm))
3084 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (parm));
3085 int align = STACK_SLOT_ALIGNMENT (TREE_TYPE (parm),
3087 TYPE_ALIGN (TREE_TYPE (parm)));
3089 /* split_complex_arg put the real and imag parts in
3090 pseudos. Move them to memory. */
3091 tmp = assign_stack_local (DECL_MODE (parm), size, align);
3092 set_mem_attributes (tmp, parm, 1);
3093 rmem = adjust_address_nv (tmp, inner, 0);
3094 imem = adjust_address_nv (tmp, inner, GET_MODE_SIZE (inner));
3095 push_to_sequence2 (all->first_conversion_insn,
3096 all->last_conversion_insn);
3097 emit_move_insn (rmem, real);
3098 emit_move_insn (imem, imag);
3099 all->first_conversion_insn = get_insns ();
3100 all->last_conversion_insn = get_last_insn ();
3104 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3105 SET_DECL_RTL (parm, tmp);
3107 real = DECL_INCOMING_RTL (VEC_index (tree, fnargs, i));
3108 imag = DECL_INCOMING_RTL (VEC_index (tree, fnargs, i + 1));
3109 if (inner != GET_MODE (real))
3111 real = gen_lowpart_SUBREG (inner, real);
3112 imag = gen_lowpart_SUBREG (inner, imag);
3114 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3115 set_decl_incoming_rtl (parm, tmp, false);
3121 /* Assign RTL expressions to the function's parameters. This may involve
3122 copying them into registers and using those registers as the DECL_RTL. */
3125 assign_parms (tree fndecl)
3127 struct assign_parm_data_all all;
3129 VEC(tree, heap) *fnargs;
3132 crtl->args.internal_arg_pointer
3133 = targetm.calls.internal_arg_pointer ();
3135 assign_parms_initialize_all (&all);
3136 fnargs = assign_parms_augmented_arg_list (&all);
3138 for (i = 0; VEC_iterate (tree, fnargs, i, parm); ++i)
3140 struct assign_parm_data_one data;
3142 /* Extract the type of PARM; adjust it according to ABI. */
3143 assign_parm_find_data_types (&all, parm, &data);
3145 /* Early out for errors and void parameters. */
3146 if (data.passed_mode == VOIDmode)
3148 SET_DECL_RTL (parm, const0_rtx);
3149 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
3153 /* Estimate stack alignment from parameter alignment. */
3154 if (SUPPORTS_STACK_ALIGNMENT)
3156 unsigned int align = FUNCTION_ARG_BOUNDARY (data.promoted_mode,
3158 align = MINIMUM_ALIGNMENT (data.passed_type, data.promoted_mode,
3160 if (TYPE_ALIGN (data.nominal_type) > align)
3161 align = MINIMUM_ALIGNMENT (data.nominal_type,
3162 TYPE_MODE (data.nominal_type),
3163 TYPE_ALIGN (data.nominal_type));
3164 if (crtl->stack_alignment_estimated < align)
3166 gcc_assert (!crtl->stack_realign_processed);
3167 crtl->stack_alignment_estimated = align;
3171 if (cfun->stdarg && !TREE_CHAIN (parm))
3172 assign_parms_setup_varargs (&all, &data, false);
3174 /* Find out where the parameter arrives in this function. */
3175 assign_parm_find_entry_rtl (&all, &data);
3177 /* Find out where stack space for this parameter might be. */
3178 if (assign_parm_is_stack_parm (&all, &data))
3180 assign_parm_find_stack_rtl (parm, &data);
3181 assign_parm_adjust_entry_rtl (&data);
3184 /* Record permanently how this parm was passed. */
3185 set_decl_incoming_rtl (parm, data.entry_parm, data.passed_pointer);
3187 /* Update info on where next arg arrives in registers. */
3188 FUNCTION_ARG_ADVANCE (all.args_so_far, data.promoted_mode,
3189 data.passed_type, data.named_arg);
3191 assign_parm_adjust_stack_rtl (&data);
3193 if (assign_parm_setup_block_p (&data))
3194 assign_parm_setup_block (&all, parm, &data);
3195 else if (data.passed_pointer || use_register_for_decl (parm))
3196 assign_parm_setup_reg (&all, parm, &data);
3198 assign_parm_setup_stack (&all, parm, &data);
3201 if (targetm.calls.split_complex_arg)
3202 assign_parms_unsplit_complex (&all, fnargs);
3204 VEC_free (tree, heap, fnargs);
3206 /* Output all parameter conversion instructions (possibly including calls)
3207 now that all parameters have been copied out of hard registers. */
3208 emit_insn (all.first_conversion_insn);
3210 /* Estimate reload stack alignment from scalar return mode. */
3211 if (SUPPORTS_STACK_ALIGNMENT)
3213 if (DECL_RESULT (fndecl))
3215 tree type = TREE_TYPE (DECL_RESULT (fndecl));
3216 enum machine_mode mode = TYPE_MODE (type);
3220 && !AGGREGATE_TYPE_P (type))
3222 unsigned int align = GET_MODE_ALIGNMENT (mode);
3223 if (crtl->stack_alignment_estimated < align)
3225 gcc_assert (!crtl->stack_realign_processed);
3226 crtl->stack_alignment_estimated = align;
3232 /* If we are receiving a struct value address as the first argument, set up
3233 the RTL for the function result. As this might require code to convert
3234 the transmitted address to Pmode, we do this here to ensure that possible
3235 preliminary conversions of the address have been emitted already. */
3236 if (all.function_result_decl)
3238 tree result = DECL_RESULT (current_function_decl);
3239 rtx addr = DECL_RTL (all.function_result_decl);
3242 if (DECL_BY_REFERENCE (result))
3246 addr = convert_memory_address (Pmode, addr);
3247 x = gen_rtx_MEM (DECL_MODE (result), addr);
3248 set_mem_attributes (x, result, 1);
3250 SET_DECL_RTL (result, x);
3253 /* We have aligned all the args, so add space for the pretend args. */
3254 crtl->args.pretend_args_size = all.pretend_args_size;
3255 all.stack_args_size.constant += all.extra_pretend_bytes;
3256 crtl->args.size = all.stack_args_size.constant;
3258 /* Adjust function incoming argument size for alignment and
3261 #ifdef REG_PARM_STACK_SPACE
3262 crtl->args.size = MAX (crtl->args.size,
3263 REG_PARM_STACK_SPACE (fndecl));
3266 crtl->args.size = CEIL_ROUND (crtl->args.size,
3267 PARM_BOUNDARY / BITS_PER_UNIT);
3269 #ifdef ARGS_GROW_DOWNWARD
3270 crtl->args.arg_offset_rtx
3271 = (all.stack_args_size.var == 0 ? GEN_INT (-all.stack_args_size.constant)
3272 : expand_expr (size_diffop (all.stack_args_size.var,
3273 size_int (-all.stack_args_size.constant)),
3274 NULL_RTX, VOIDmode, EXPAND_NORMAL));
3276 crtl->args.arg_offset_rtx = ARGS_SIZE_RTX (all.stack_args_size);
3279 /* See how many bytes, if any, of its args a function should try to pop
3282 crtl->args.pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
3285 /* For stdarg.h function, save info about
3286 regs and stack space used by the named args. */
3288 crtl->args.info = all.args_so_far;
3290 /* Set the rtx used for the function return value. Put this in its
3291 own variable so any optimizers that need this information don't have
3292 to include tree.h. Do this here so it gets done when an inlined
3293 function gets output. */
3296 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
3297 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
3299 /* If scalar return value was computed in a pseudo-reg, or was a named
3300 return value that got dumped to the stack, copy that to the hard
3302 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
3304 tree decl_result = DECL_RESULT (fndecl);
3305 rtx decl_rtl = DECL_RTL (decl_result);
3307 if (REG_P (decl_rtl)
3308 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
3309 : DECL_REGISTER (decl_result))
3313 real_decl_rtl = targetm.calls.function_value (TREE_TYPE (decl_result),
3315 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
3316 /* The delay slot scheduler assumes that crtl->return_rtx
3317 holds the hard register containing the return value, not a
3318 temporary pseudo. */
3319 crtl->return_rtx = real_decl_rtl;
3324 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3325 For all seen types, gimplify their sizes. */
3328 gimplify_parm_type (tree *tp, int *walk_subtrees, void *data)
3335 if (POINTER_TYPE_P (t))
3337 else if (TYPE_SIZE (t) && !TREE_CONSTANT (TYPE_SIZE (t))
3338 && !TYPE_SIZES_GIMPLIFIED (t))
3340 gimplify_type_sizes (t, (gimple_seq *) data);
3348 /* Gimplify the parameter list for current_function_decl. This involves
3349 evaluating SAVE_EXPRs of variable sized parameters and generating code
3350 to implement callee-copies reference parameters. Returns a sequence of
3351 statements to add to the beginning of the function. */
3354 gimplify_parameters (void)
3356 struct assign_parm_data_all all;
3358 gimple_seq stmts = NULL;
3359 VEC(tree, heap) *fnargs;
3362 assign_parms_initialize_all (&all);
3363 fnargs = assign_parms_augmented_arg_list (&all);
3365 for (i = 0; VEC_iterate (tree, fnargs, i, parm); ++i)
3367 struct assign_parm_data_one data;
3369 /* Extract the type of PARM; adjust it according to ABI. */
3370 assign_parm_find_data_types (&all, parm, &data);
3372 /* Early out for errors and void parameters. */
3373 if (data.passed_mode == VOIDmode || DECL_SIZE (parm) == NULL)
3376 /* Update info on where next arg arrives in registers. */
3377 FUNCTION_ARG_ADVANCE (all.args_so_far, data.promoted_mode,
3378 data.passed_type, data.named_arg);
3380 /* ??? Once upon a time variable_size stuffed parameter list
3381 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3382 turned out to be less than manageable in the gimple world.
3383 Now we have to hunt them down ourselves. */
3384 walk_tree_without_duplicates (&data.passed_type,
3385 gimplify_parm_type, &stmts);
3387 if (TREE_CODE (DECL_SIZE_UNIT (parm)) != INTEGER_CST)
3389 gimplify_one_sizepos (&DECL_SIZE (parm), &stmts);
3390 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm), &stmts);
3393 if (data.passed_pointer)
3395 tree type = TREE_TYPE (data.passed_type);
3396 if (reference_callee_copied (&all.args_so_far, TYPE_MODE (type),
3397 type, data.named_arg))
3401 /* For constant-sized objects, this is trivial; for
3402 variable-sized objects, we have to play games. */
3403 if (TREE_CODE (DECL_SIZE_UNIT (parm)) == INTEGER_CST
3404 && !(flag_stack_check == GENERIC_STACK_CHECK
3405 && compare_tree_int (DECL_SIZE_UNIT (parm),
3406 STACK_CHECK_MAX_VAR_SIZE) > 0))
3408 local = create_tmp_var (type, get_name (parm));
3409 DECL_IGNORED_P (local) = 0;
3410 /* If PARM was addressable, move that flag over
3411 to the local copy, as its address will be taken,
3413 if (TREE_ADDRESSABLE (parm))
3415 TREE_ADDRESSABLE (parm) = 0;
3416 TREE_ADDRESSABLE (local) = 1;
3421 tree ptr_type, addr;
3423 ptr_type = build_pointer_type (type);
3424 addr = create_tmp_var (ptr_type, get_name (parm));
3425 DECL_IGNORED_P (addr) = 0;
3426 local = build_fold_indirect_ref (addr);
3428 t = built_in_decls[BUILT_IN_ALLOCA];
3429 t = build_call_expr (t, 1, DECL_SIZE_UNIT (parm));
3430 t = fold_convert (ptr_type, t);
3431 t = build2 (MODIFY_EXPR, TREE_TYPE (addr), addr, t);
3432 gimplify_and_add (t, &stmts);
3435 gimplify_assign (local, parm, &stmts);
3437 SET_DECL_VALUE_EXPR (parm, local);
3438 DECL_HAS_VALUE_EXPR_P (parm) = 1;
3443 VEC_free (tree, heap, fnargs);
3448 /* Compute the size and offset from the start of the stacked arguments for a
3449 parm passed in mode PASSED_MODE and with type TYPE.
3451 INITIAL_OFFSET_PTR points to the current offset into the stacked
3454 The starting offset and size for this parm are returned in
3455 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3456 nonzero, the offset is that of stack slot, which is returned in
3457 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3458 padding required from the initial offset ptr to the stack slot.
3460 IN_REGS is nonzero if the argument will be passed in registers. It will
3461 never be set if REG_PARM_STACK_SPACE is not defined.
3463 FNDECL is the function in which the argument was defined.
3465 There are two types of rounding that are done. The first, controlled by
3466 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
3467 list to be aligned to the specific boundary (in bits). This rounding
3468 affects the initial and starting offsets, but not the argument size.
3470 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3471 optionally rounds the size of the parm to PARM_BOUNDARY. The
3472 initial offset is not affected by this rounding, while the size always
3473 is and the starting offset may be. */
3475 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3476 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3477 callers pass in the total size of args so far as
3478 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
3481 locate_and_pad_parm (enum machine_mode passed_mode, tree type, int in_regs,
3482 int partial, tree fndecl ATTRIBUTE_UNUSED,
3483 struct args_size *initial_offset_ptr,
3484 struct locate_and_pad_arg_data *locate)
3487 enum direction where_pad;
3488 unsigned int boundary;
3489 int reg_parm_stack_space = 0;
3490 int part_size_in_regs;
3492 #ifdef REG_PARM_STACK_SPACE
3493 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
3495 /* If we have found a stack parm before we reach the end of the
3496 area reserved for registers, skip that area. */
3499 if (reg_parm_stack_space > 0)
3501 if (initial_offset_ptr->var)
3503 initial_offset_ptr->var
3504 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
3505 ssize_int (reg_parm_stack_space));
3506 initial_offset_ptr->constant = 0;
3508 else if (initial_offset_ptr->constant < reg_parm_stack_space)
3509 initial_offset_ptr->constant = reg_parm_stack_space;
3512 #endif /* REG_PARM_STACK_SPACE */
3514 part_size_in_regs = (reg_parm_stack_space == 0 ? partial : 0);
3517 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
3518 where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
3519 boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
3520 locate->where_pad = where_pad;
3522 /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT. */
3523 if (boundary > MAX_SUPPORTED_STACK_ALIGNMENT)
3524 boundary = MAX_SUPPORTED_STACK_ALIGNMENT;
3526 locate->boundary = boundary;
3528 if (SUPPORTS_STACK_ALIGNMENT)
3530 /* stack_alignment_estimated can't change after stack has been
3532 if (crtl->stack_alignment_estimated < boundary)
3534 if (!crtl->stack_realign_processed)
3535 crtl->stack_alignment_estimated = boundary;
3538 /* If stack is realigned and stack alignment value
3539 hasn't been finalized, it is OK not to increase
3540 stack_alignment_estimated. The bigger alignment
3541 requirement is recorded in stack_alignment_needed
3543 gcc_assert (!crtl->stack_realign_finalized
3544 && crtl->stack_realign_needed);
3549 /* Remember if the outgoing parameter requires extra alignment on the
3550 calling function side. */
3551 if (crtl->stack_alignment_needed < boundary)
3552 crtl->stack_alignment_needed = boundary;
3553 if (crtl->preferred_stack_boundary < boundary)
3554 crtl->preferred_stack_boundary = boundary;
3556 #ifdef ARGS_GROW_DOWNWARD
3557 locate->slot_offset.constant = -initial_offset_ptr->constant;
3558 if (initial_offset_ptr->var)
3559 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
3560 initial_offset_ptr->var);
3564 if (where_pad != none
3565 && (!host_integerp (sizetree, 1)
3566 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
3567 s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
3568 SUB_PARM_SIZE (locate->slot_offset, s2);
3571 locate->slot_offset.constant += part_size_in_regs;
3574 #ifdef REG_PARM_STACK_SPACE
3575 || REG_PARM_STACK_SPACE (fndecl) > 0
3578 pad_to_arg_alignment (&locate->slot_offset, boundary,
3579 &locate->alignment_pad);
3581 locate->size.constant = (-initial_offset_ptr->constant
3582 - locate->slot_offset.constant);
3583 if (initial_offset_ptr->var)
3584 locate->size.var = size_binop (MINUS_EXPR,
3585 size_binop (MINUS_EXPR,
3587 initial_offset_ptr->var),
3588 locate->slot_offset.var);
3590 /* Pad_below needs the pre-rounded size to know how much to pad
3592 locate->offset = locate->slot_offset;
3593 if (where_pad == downward)
3594 pad_below (&locate->offset, passed_mode, sizetree);
3596 #else /* !ARGS_GROW_DOWNWARD */
3598 #ifdef REG_PARM_STACK_SPACE
3599 || REG_PARM_STACK_SPACE (fndecl) > 0
3602 pad_to_arg_alignment (initial_offset_ptr, boundary,
3603 &locate->alignment_pad);
3604 locate->slot_offset = *initial_offset_ptr;
3606 #ifdef PUSH_ROUNDING
3607 if (passed_mode != BLKmode)
3608 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
3611 /* Pad_below needs the pre-rounded size to know how much to pad below
3612 so this must be done before rounding up. */
3613 locate->offset = locate->slot_offset;
3614 if (where_pad == downward)
3615 pad_below (&locate->offset, passed_mode, sizetree);
3617 if (where_pad != none
3618 && (!host_integerp (sizetree, 1)
3619 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
3620 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
3622 ADD_PARM_SIZE (locate->size, sizetree);
3624 locate->size.constant -= part_size_in_regs;
3625 #endif /* ARGS_GROW_DOWNWARD */
3627 #ifdef FUNCTION_ARG_OFFSET
3628 locate->offset.constant += FUNCTION_ARG_OFFSET (passed_mode, type);
3632 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
3633 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
3636 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
3637 struct args_size *alignment_pad)
3639 tree save_var = NULL_TREE;
3640 HOST_WIDE_INT save_constant = 0;
3641 int boundary_in_bytes = boundary / BITS_PER_UNIT;
3642 HOST_WIDE_INT sp_offset = STACK_POINTER_OFFSET;
3644 #ifdef SPARC_STACK_BOUNDARY_HACK
3645 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
3646 the real alignment of %sp. However, when it does this, the
3647 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
3648 if (SPARC_STACK_BOUNDARY_HACK)
3652 if (boundary > PARM_BOUNDARY)
3654 save_var = offset_ptr->var;
3655 save_constant = offset_ptr->constant;
3658 alignment_pad->var = NULL_TREE;
3659 alignment_pad->constant = 0;
3661 if (boundary > BITS_PER_UNIT)
3663 if (offset_ptr->var)
3665 tree sp_offset_tree = ssize_int (sp_offset);
3666 tree offset = size_binop (PLUS_EXPR,
3667 ARGS_SIZE_TREE (*offset_ptr),
3669 #ifdef ARGS_GROW_DOWNWARD
3670 tree rounded = round_down (offset, boundary / BITS_PER_UNIT);
3672 tree rounded = round_up (offset, boundary / BITS_PER_UNIT);
3675 offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
3676 /* ARGS_SIZE_TREE includes constant term. */
3677 offset_ptr->constant = 0;
3678 if (boundary > PARM_BOUNDARY)
3679 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
3684 offset_ptr->constant = -sp_offset +
3685 #ifdef ARGS_GROW_DOWNWARD
3686 FLOOR_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
3688 CEIL_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
3690 if (boundary > PARM_BOUNDARY)
3691 alignment_pad->constant = offset_ptr->constant - save_constant;
3697 pad_below (struct args_size *offset_ptr, enum machine_mode passed_mode, tree sizetree)
3699 if (passed_mode != BLKmode)
3701 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
3702 offset_ptr->constant
3703 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
3704 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
3705 - GET_MODE_SIZE (passed_mode));
3709 if (TREE_CODE (sizetree) != INTEGER_CST
3710 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
3712 /* Round the size up to multiple of PARM_BOUNDARY bits. */
3713 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
3715 ADD_PARM_SIZE (*offset_ptr, s2);
3716 SUB_PARM_SIZE (*offset_ptr, sizetree);
3722 /* True if register REGNO was alive at a place where `setjmp' was
3723 called and was set more than once or is an argument. Such regs may
3724 be clobbered by `longjmp'. */
3727 regno_clobbered_at_setjmp (bitmap setjmp_crosses, int regno)
3729 /* There appear to be cases where some local vars never reach the
3730 backend but have bogus regnos. */
3731 if (regno >= max_reg_num ())
3734 return ((REG_N_SETS (regno) > 1
3735 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR), regno))
3736 && REGNO_REG_SET_P (setjmp_crosses, regno));
3739 /* Walk the tree of blocks describing the binding levels within a
3740 function and warn about variables the might be killed by setjmp or
3741 vfork. This is done after calling flow_analysis before register
3742 allocation since that will clobber the pseudo-regs to hard
3746 setjmp_vars_warning (bitmap setjmp_crosses, tree block)
3750 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
3752 if (TREE_CODE (decl) == VAR_DECL
3753 && DECL_RTL_SET_P (decl)
3754 && REG_P (DECL_RTL (decl))
3755 && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
3756 warning (OPT_Wclobbered, "variable %q+D might be clobbered by"
3757 " %<longjmp%> or %<vfork%>", decl);
3760 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = BLOCK_CHAIN (sub))
3761 setjmp_vars_warning (setjmp_crosses, sub);
3764 /* Do the appropriate part of setjmp_vars_warning
3765 but for arguments instead of local variables. */
3768 setjmp_args_warning (bitmap setjmp_crosses)
3771 for (decl = DECL_ARGUMENTS (current_function_decl);
3772 decl; decl = TREE_CHAIN (decl))
3773 if (DECL_RTL (decl) != 0
3774 && REG_P (DECL_RTL (decl))
3775 && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
3776 warning (OPT_Wclobbered,
3777 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
3781 /* Generate warning messages for variables live across setjmp. */
3784 generate_setjmp_warnings (void)
3786 bitmap setjmp_crosses = regstat_get_setjmp_crosses ();
3788 if (n_basic_blocks == NUM_FIXED_BLOCKS
3789 || bitmap_empty_p (setjmp_crosses))
3792 setjmp_vars_warning (setjmp_crosses, DECL_INITIAL (current_function_decl));
3793 setjmp_args_warning (setjmp_crosses);
3797 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
3798 and create duplicate blocks. */
3799 /* ??? Need an option to either create block fragments or to create
3800 abstract origin duplicates of a source block. It really depends
3801 on what optimization has been performed. */
3804 reorder_blocks (void)
3806 tree block = DECL_INITIAL (current_function_decl);
3807 VEC(tree,heap) *block_stack;
3809 if (block == NULL_TREE)
3812 block_stack = VEC_alloc (tree, heap, 10);
3814 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
3815 clear_block_marks (block);
3817 /* Prune the old trees away, so that they don't get in the way. */
3818 BLOCK_SUBBLOCKS (block) = NULL_TREE;
3819 BLOCK_CHAIN (block) = NULL_TREE;
3821 /* Recreate the block tree from the note nesting. */
3822 reorder_blocks_1 (get_insns (), block, &block_stack);
3823 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
3825 VEC_free (tree, heap, block_stack);
3828 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
3831 clear_block_marks (tree block)
3835 TREE_ASM_WRITTEN (block) = 0;
3836 clear_block_marks (BLOCK_SUBBLOCKS (block));
3837 block = BLOCK_CHAIN (block);
3842 reorder_blocks_1 (rtx insns, tree current_block, VEC(tree,heap) **p_block_stack)
3846 for (insn = insns; insn; insn = NEXT_INSN (insn))
3850 if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_BEG)
3852 tree block = NOTE_BLOCK (insn);
3855 origin = (BLOCK_FRAGMENT_ORIGIN (block)
3856 ? BLOCK_FRAGMENT_ORIGIN (block)
3859 /* If we have seen this block before, that means it now
3860 spans multiple address regions. Create a new fragment. */
3861 if (TREE_ASM_WRITTEN (block))
3863 tree new_block = copy_node (block);
3865 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
3866 BLOCK_FRAGMENT_CHAIN (new_block)
3867 = BLOCK_FRAGMENT_CHAIN (origin);
3868 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
3870 NOTE_BLOCK (insn) = new_block;
3874 BLOCK_SUBBLOCKS (block) = 0;
3875 TREE_ASM_WRITTEN (block) = 1;
3876 /* When there's only one block for the entire function,
3877 current_block == block and we mustn't do this, it
3878 will cause infinite recursion. */
3879 if (block != current_block)
3881 if (block != origin)
3882 gcc_assert (BLOCK_SUPERCONTEXT (origin) == current_block);
3884 BLOCK_SUPERCONTEXT (block) = current_block;
3885 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
3886 BLOCK_SUBBLOCKS (current_block) = block;
3887 current_block = origin;
3889 VEC_safe_push (tree, heap, *p_block_stack, block);
3891 else if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_END)
3893 NOTE_BLOCK (insn) = VEC_pop (tree, *p_block_stack);
3894 BLOCK_SUBBLOCKS (current_block)
3895 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
3896 current_block = BLOCK_SUPERCONTEXT (current_block);
3902 /* Reverse the order of elements in the chain T of blocks,
3903 and return the new head of the chain (old last element). */
3906 blocks_nreverse (tree t)
3908 tree prev = 0, decl, next;
3909 for (decl = t; decl; decl = next)
3911 next = BLOCK_CHAIN (decl);
3912 BLOCK_CHAIN (decl) = prev;
3918 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
3919 non-NULL, list them all into VECTOR, in a depth-first preorder
3920 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
3924 all_blocks (tree block, tree *vector)
3930 TREE_ASM_WRITTEN (block) = 0;
3932 /* Record this block. */
3934 vector[n_blocks] = block;
3938 /* Record the subblocks, and their subblocks... */
3939 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
3940 vector ? vector + n_blocks : 0);
3941 block = BLOCK_CHAIN (block);
3947 /* Return a vector containing all the blocks rooted at BLOCK. The
3948 number of elements in the vector is stored in N_BLOCKS_P. The
3949 vector is dynamically allocated; it is the caller's responsibility
3950 to call `free' on the pointer returned. */
3953 get_block_vector (tree block, int *n_blocks_p)
3957 *n_blocks_p = all_blocks (block, NULL);
3958 block_vector = XNEWVEC (tree, *n_blocks_p);
3959 all_blocks (block, block_vector);
3961 return block_vector;
3964 static GTY(()) int next_block_index = 2;
3966 /* Set BLOCK_NUMBER for all the blocks in FN. */
3969 number_blocks (tree fn)
3975 /* For SDB and XCOFF debugging output, we start numbering the blocks
3976 from 1 within each function, rather than keeping a running
3978 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
3979 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
3980 next_block_index = 1;
3983 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
3985 /* The top-level BLOCK isn't numbered at all. */
3986 for (i = 1; i < n_blocks; ++i)
3987 /* We number the blocks from two. */
3988 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
3990 free (block_vector);
3995 /* If VAR is present in a subblock of BLOCK, return the subblock. */
3998 debug_find_var_in_block_tree (tree var, tree block)
4002 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
4006 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
4008 tree ret = debug_find_var_in_block_tree (var, t);
4016 /* Keep track of whether we're in a dummy function context. If we are,
4017 we don't want to invoke the set_current_function hook, because we'll
4018 get into trouble if the hook calls target_reinit () recursively or
4019 when the initial initialization is not yet complete. */
4021 static bool in_dummy_function;
4023 /* Invoke the target hook when setting cfun. Update the optimization options
4024 if the function uses different options than the default. */
4027 invoke_set_current_function_hook (tree fndecl)
4029 if (!in_dummy_function)
4031 tree opts = ((fndecl)
4032 ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl)
4033 : optimization_default_node);
4036 opts = optimization_default_node;
4038 /* Change optimization options if needed. */
4039 if (optimization_current_node != opts)
4041 optimization_current_node = opts;
4042 cl_optimization_restore (TREE_OPTIMIZATION (opts));
4045 targetm.set_current_function (fndecl);
4049 /* cfun should never be set directly; use this function. */
4052 set_cfun (struct function *new_cfun)
4054 if (cfun != new_cfun)
4057 invoke_set_current_function_hook (new_cfun ? new_cfun->decl : NULL_TREE);
4061 /* Initialized with NOGC, making this poisonous to the garbage collector. */
4063 static VEC(function_p,heap) *cfun_stack;
4065 /* Push the current cfun onto the stack, and set cfun to new_cfun. */
4068 push_cfun (struct function *new_cfun)
4070 VEC_safe_push (function_p, heap, cfun_stack, cfun);
4071 set_cfun (new_cfun);
4074 /* Pop cfun from the stack. */
4079 struct function *new_cfun = VEC_pop (function_p, cfun_stack);
4080 set_cfun (new_cfun);
4083 /* Return value of funcdef and increase it. */
4085 get_next_funcdef_no (void)
4087 return funcdef_no++;
4090 /* Allocate a function structure for FNDECL and set its contents
4091 to the defaults. Set cfun to the newly-allocated object.
4092 Some of the helper functions invoked during initialization assume
4093 that cfun has already been set. Therefore, assign the new object
4094 directly into cfun and invoke the back end hook explicitly at the
4095 very end, rather than initializing a temporary and calling set_cfun
4098 ABSTRACT_P is true if this is a function that will never be seen by
4099 the middle-end. Such functions are front-end concepts (like C++
4100 function templates) that do not correspond directly to functions
4101 placed in object files. */
4104 allocate_struct_function (tree fndecl, bool abstract_p)
4107 tree fntype = fndecl ? TREE_TYPE (fndecl) : NULL_TREE;
4109 cfun = GGC_CNEW (struct function);
4111 cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL;
4113 init_eh_for_function ();
4115 if (init_machine_status)
4116 cfun->machine = (*init_machine_status) ();
4118 #ifdef OVERRIDE_ABI_FORMAT
4119 OVERRIDE_ABI_FORMAT (fndecl);
4122 invoke_set_current_function_hook (fndecl);
4124 if (fndecl != NULL_TREE)
4126 DECL_STRUCT_FUNCTION (fndecl) = cfun;
4127 cfun->decl = fndecl;
4128 current_function_funcdef_no = get_next_funcdef_no ();
4130 result = DECL_RESULT (fndecl);
4131 if (!abstract_p && aggregate_value_p (result, fndecl))
4133 #ifdef PCC_STATIC_STRUCT_RETURN
4134 cfun->returns_pcc_struct = 1;
4136 cfun->returns_struct = 1;
4141 && TYPE_ARG_TYPES (fntype) != 0
4142 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4143 != void_type_node));
4145 /* Assume all registers in stdarg functions need to be saved. */
4146 cfun->va_list_gpr_size = VA_LIST_MAX_GPR_SIZE;
4147 cfun->va_list_fpr_size = VA_LIST_MAX_FPR_SIZE;
4151 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
4152 instead of just setting it. */
4155 push_struct_function (tree fndecl)
4157 VEC_safe_push (function_p, heap, cfun_stack, cfun);
4158 allocate_struct_function (fndecl, false);
4161 /* Reset cfun, and other non-struct-function variables to defaults as
4162 appropriate for emitting rtl at the start of a function. */
4165 prepare_function_start (void)
4167 gcc_assert (!crtl->emit.x_last_insn);
4170 init_varasm_status ();
4172 default_rtl_profile ();
4174 cse_not_expected = ! optimize;
4176 /* Caller save not needed yet. */
4177 caller_save_needed = 0;
4179 /* We haven't done register allocation yet. */
4182 /* Indicate that we have not instantiated virtual registers yet. */
4183 virtuals_instantiated = 0;
4185 /* Indicate that we want CONCATs now. */
4186 generating_concat_p = 1;
4188 /* Indicate we have no need of a frame pointer yet. */
4189 frame_pointer_needed = 0;
4192 /* Initialize the rtl expansion mechanism so that we can do simple things
4193 like generate sequences. This is used to provide a context during global
4194 initialization of some passes. You must call expand_dummy_function_end
4195 to exit this context. */
4198 init_dummy_function_start (void)
4200 gcc_assert (!in_dummy_function);
4201 in_dummy_function = true;
4202 push_struct_function (NULL_TREE);
4203 prepare_function_start ();
4206 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
4207 and initialize static variables for generating RTL for the statements
4211 init_function_start (tree subr)
4213 if (subr && DECL_STRUCT_FUNCTION (subr))
4214 set_cfun (DECL_STRUCT_FUNCTION (subr));
4216 allocate_struct_function (subr, false);
4217 prepare_function_start ();
4219 /* Warn if this value is an aggregate type,
4220 regardless of which calling convention we are using for it. */
4221 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
4222 warning (OPT_Waggregate_return, "function returns an aggregate");
4225 /* Make sure all values used by the optimization passes have sane defaults. */
4227 init_function_for_compilation (void)
4233 struct rtl_opt_pass pass_init_function =
4237 "*init_function", /* name */
4239 init_function_for_compilation, /* execute */
4242 0, /* static_pass_number */
4243 TV_NONE, /* tv_id */
4244 0, /* properties_required */
4245 0, /* properties_provided */
4246 0, /* properties_destroyed */
4247 0, /* todo_flags_start */
4248 0 /* todo_flags_finish */
4254 expand_main_function (void)
4256 #if (defined(INVOKE__main) \
4257 || (!defined(HAS_INIT_SECTION) \
4258 && !defined(INIT_SECTION_ASM_OP) \
4259 && !defined(INIT_ARRAY_SECTION_ASM_OP)))
4260 emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0);
4264 /* Expand code to initialize the stack_protect_guard. This is invoked at
4265 the beginning of a function to be protected. */
4267 #ifndef HAVE_stack_protect_set
4268 # define HAVE_stack_protect_set 0
4269 # define gen_stack_protect_set(x,y) (gcc_unreachable (), NULL_RTX)
4273 stack_protect_prologue (void)
4275 tree guard_decl = targetm.stack_protect_guard ();
4278 x = expand_normal (crtl->stack_protect_guard);
4279 y = expand_normal (guard_decl);
4281 /* Allow the target to copy from Y to X without leaking Y into a
4283 if (HAVE_stack_protect_set)
4285 rtx insn = gen_stack_protect_set (x, y);
4293 /* Otherwise do a straight move. */
4294 emit_move_insn (x, y);
4297 /* Expand code to verify the stack_protect_guard. This is invoked at
4298 the end of a function to be protected. */
4300 #ifndef HAVE_stack_protect_test
4301 # define HAVE_stack_protect_test 0
4302 # define gen_stack_protect_test(x, y, z) (gcc_unreachable (), NULL_RTX)
4306 stack_protect_epilogue (void)
4308 tree guard_decl = targetm.stack_protect_guard ();
4309 rtx label = gen_label_rtx ();
4312 x = expand_normal (crtl->stack_protect_guard);
4313 y = expand_normal (guard_decl);
4315 /* Allow the target to compare Y with X without leaking either into
4317 switch (HAVE_stack_protect_test != 0)
4320 tmp = gen_stack_protect_test (x, y, label);
4329 emit_cmp_and_jump_insns (x, y, EQ, NULL_RTX, ptr_mode, 1, label);
4333 /* The noreturn predictor has been moved to the tree level. The rtl-level
4334 predictors estimate this branch about 20%, which isn't enough to get
4335 things moved out of line. Since this is the only extant case of adding
4336 a noreturn function at the rtl level, it doesn't seem worth doing ought
4337 except adding the prediction by hand. */
4338 tmp = get_last_insn ();
4340 predict_insn_def (tmp, PRED_NORETURN, TAKEN);
4342 expand_expr_stmt (targetm.stack_protect_fail ());
4346 /* Start the RTL for a new function, and set variables used for
4348 SUBR is the FUNCTION_DECL node.
4349 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4350 the function's parameters, which must be run at any return statement. */
4353 expand_function_start (tree subr)
4355 /* Make sure volatile mem refs aren't considered
4356 valid operands of arithmetic insns. */
4357 init_recog_no_volatile ();
4361 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
4364 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
4366 /* Make the label for return statements to jump to. Do not special
4367 case machines with special return instructions -- they will be
4368 handled later during jump, ifcvt, or epilogue creation. */
4369 return_label = gen_label_rtx ();
4371 /* Initialize rtx used to return the value. */
4372 /* Do this before assign_parms so that we copy the struct value address
4373 before any library calls that assign parms might generate. */
4375 /* Decide whether to return the value in memory or in a register. */
4376 if (aggregate_value_p (DECL_RESULT (subr), subr))
4378 /* Returning something that won't go in a register. */
4379 rtx value_address = 0;
4381 #ifdef PCC_STATIC_STRUCT_RETURN
4382 if (cfun->returns_pcc_struct)
4384 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
4385 value_address = assemble_static_space (size);
4390 rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 2);
4391 /* Expect to be passed the address of a place to store the value.
4392 If it is passed as an argument, assign_parms will take care of
4396 value_address = gen_reg_rtx (Pmode);
4397 emit_move_insn (value_address, sv);
4402 rtx x = value_address;
4403 if (!DECL_BY_REFERENCE (DECL_RESULT (subr)))
4405 x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), x);
4406 set_mem_attributes (x, DECL_RESULT (subr), 1);
4408 SET_DECL_RTL (DECL_RESULT (subr), x);
4411 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
4412 /* If return mode is void, this decl rtl should not be used. */
4413 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
4416 /* Compute the return values into a pseudo reg, which we will copy
4417 into the true return register after the cleanups are done. */
4418 tree return_type = TREE_TYPE (DECL_RESULT (subr));
4419 if (TYPE_MODE (return_type) != BLKmode
4420 && targetm.calls.return_in_msb (return_type))
4421 /* expand_function_end will insert the appropriate padding in
4422 this case. Use the return value's natural (unpadded) mode
4423 within the function proper. */
4424 SET_DECL_RTL (DECL_RESULT (subr),
4425 gen_reg_rtx (TYPE_MODE (return_type)));
4428 /* In order to figure out what mode to use for the pseudo, we
4429 figure out what the mode of the eventual return register will
4430 actually be, and use that. */
4431 rtx hard_reg = hard_function_value (return_type, subr, 0, 1);
4433 /* Structures that are returned in registers are not
4434 aggregate_value_p, so we may see a PARALLEL or a REG. */
4435 if (REG_P (hard_reg))
4436 SET_DECL_RTL (DECL_RESULT (subr),
4437 gen_reg_rtx (GET_MODE (hard_reg)));
4440 gcc_assert (GET_CODE (hard_reg) == PARALLEL);
4441 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
4445 /* Set DECL_REGISTER flag so that expand_function_end will copy the
4446 result to the real return register(s). */
4447 DECL_REGISTER (DECL_RESULT (subr)) = 1;
4450 /* Initialize rtx for parameters and local variables.
4451 In some cases this requires emitting insns. */
4452 assign_parms (subr);
4454 /* If function gets a static chain arg, store it. */
4455 if (cfun->static_chain_decl)
4457 tree parm = cfun->static_chain_decl;
4458 rtx local, chain, insn;
4460 local = gen_reg_rtx (Pmode);
4461 chain = targetm.calls.static_chain (current_function_decl, true);
4463 set_decl_incoming_rtl (parm, chain, false);
4464 SET_DECL_RTL (parm, local);
4465 mark_reg_pointer (local, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
4467 insn = emit_move_insn (local, chain);
4469 /* Mark the register as eliminable, similar to parameters. */
4471 && reg_mentioned_p (arg_pointer_rtx, XEXP (chain, 0)))
4472 set_unique_reg_note (insn, REG_EQUIV, chain);
4475 /* If the function receives a non-local goto, then store the
4476 bits we need to restore the frame pointer. */
4477 if (cfun->nonlocal_goto_save_area)
4482 /* ??? We need to do this save early. Unfortunately here is
4483 before the frame variable gets declared. Help out... */
4484 tree var = TREE_OPERAND (cfun->nonlocal_goto_save_area, 0);
4485 if (!DECL_RTL_SET_P (var))
4488 t_save = build4 (ARRAY_REF, ptr_type_node,
4489 cfun->nonlocal_goto_save_area,
4490 integer_zero_node, NULL_TREE, NULL_TREE);
4491 r_save = expand_expr (t_save, NULL_RTX, VOIDmode, EXPAND_WRITE);
4492 r_save = convert_memory_address (Pmode, r_save);
4494 emit_move_insn (r_save, targetm.builtin_setjmp_frame_value ());
4495 update_nonlocal_goto_save_area ();
4498 /* The following was moved from init_function_start.
4499 The move is supposed to make sdb output more accurate. */
4500 /* Indicate the beginning of the function body,
4501 as opposed to parm setup. */
4502 emit_note (NOTE_INSN_FUNCTION_BEG);
4504 gcc_assert (NOTE_P (get_last_insn ()));
4506 parm_birth_insn = get_last_insn ();
4511 PROFILE_HOOK (current_function_funcdef_no);
4515 /* After the display initializations is where the stack checking
4517 if(flag_stack_check)
4518 stack_check_probe_note = emit_note (NOTE_INSN_DELETED);
4520 /* Make sure there is a line number after the function entry setup code. */
4521 force_next_line_note ();
4524 /* Undo the effects of init_dummy_function_start. */
4526 expand_dummy_function_end (void)
4528 gcc_assert (in_dummy_function);
4530 /* End any sequences that failed to be closed due to syntax errors. */
4531 while (in_sequence_p ())
4534 /* Outside function body, can't compute type's actual size
4535 until next function's body starts. */
4537 free_after_parsing (cfun);
4538 free_after_compilation (cfun);
4540 in_dummy_function = false;
4543 /* Call DOIT for each hard register used as a return value from
4544 the current function. */
4547 diddle_return_value (void (*doit) (rtx, void *), void *arg)
4549 rtx outgoing = crtl->return_rtx;
4554 if (REG_P (outgoing))
4555 (*doit) (outgoing, arg);
4556 else if (GET_CODE (outgoing) == PARALLEL)
4560 for (i = 0; i < XVECLEN (outgoing, 0); i++)
4562 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
4564 if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER)
4571 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
4577 clobber_return_register (void)
4579 diddle_return_value (do_clobber_return_reg, NULL);
4581 /* In case we do use pseudo to return value, clobber it too. */
4582 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
4584 tree decl_result = DECL_RESULT (current_function_decl);
4585 rtx decl_rtl = DECL_RTL (decl_result);
4586 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
4588 do_clobber_return_reg (decl_rtl, NULL);
4594 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
4600 use_return_register (void)
4602 diddle_return_value (do_use_return_reg, NULL);
4605 /* Possibly warn about unused parameters. */
4607 do_warn_unused_parameter (tree fn)
4611 for (decl = DECL_ARGUMENTS (fn);
4612 decl; decl = TREE_CHAIN (decl))
4613 if (!TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
4614 && DECL_NAME (decl) && !DECL_ARTIFICIAL (decl)
4615 && !TREE_NO_WARNING (decl))
4616 warning (OPT_Wunused_parameter, "unused parameter %q+D", decl);
4619 static GTY(()) rtx initial_trampoline;
4621 /* Generate RTL for the end of the current function. */
4624 expand_function_end (void)
4628 /* If arg_pointer_save_area was referenced only from a nested
4629 function, we will not have initialized it yet. Do that now. */
4630 if (arg_pointer_save_area && ! crtl->arg_pointer_save_area_init)
4631 get_arg_pointer_save_area ();
4633 /* If we are doing generic stack checking and this function makes calls,
4634 do a stack probe at the start of the function to ensure we have enough
4635 space for another stack frame. */
4636 if (flag_stack_check == GENERIC_STACK_CHECK)
4640 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4643 rtx max_frame_size = GEN_INT (STACK_CHECK_MAX_FRAME_SIZE);
4645 if (STACK_CHECK_MOVING_SP)
4646 anti_adjust_stack_and_probe (max_frame_size, true);
4648 probe_stack_range (STACK_OLD_CHECK_PROTECT, max_frame_size);
4651 emit_insn_before (seq, stack_check_probe_note);
4656 /* End any sequences that failed to be closed due to syntax errors. */
4657 while (in_sequence_p ())
4660 clear_pending_stack_adjust ();
4661 do_pending_stack_adjust ();
4663 /* Output a linenumber for the end of the function.
4664 SDB depends on this. */
4665 force_next_line_note ();
4666 set_curr_insn_source_location (input_location);
4668 /* Before the return label (if any), clobber the return
4669 registers so that they are not propagated live to the rest of
4670 the function. This can only happen with functions that drop
4671 through; if there had been a return statement, there would
4672 have either been a return rtx, or a jump to the return label.
4674 We delay actual code generation after the current_function_value_rtx
4676 clobber_after = get_last_insn ();
4678 /* Output the label for the actual return from the function. */
4679 emit_label (return_label);
4681 if (USING_SJLJ_EXCEPTIONS)
4683 /* Let except.c know where it should emit the call to unregister
4684 the function context for sjlj exceptions. */
4685 if (flag_exceptions)
4686 sjlj_emit_function_exit_after (get_last_insn ());
4690 /* We want to ensure that instructions that may trap are not
4691 moved into the epilogue by scheduling, because we don't
4692 always emit unwind information for the epilogue. */
4693 if (flag_non_call_exceptions)
4694 emit_insn (gen_blockage ());
4697 /* If this is an implementation of throw, do what's necessary to
4698 communicate between __builtin_eh_return and the epilogue. */
4699 expand_eh_return ();
4701 /* If scalar return value was computed in a pseudo-reg, or was a named
4702 return value that got dumped to the stack, copy that to the hard
4704 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
4706 tree decl_result = DECL_RESULT (current_function_decl);
4707 rtx decl_rtl = DECL_RTL (decl_result);
4709 if (REG_P (decl_rtl)
4710 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
4711 : DECL_REGISTER (decl_result))
4713 rtx real_decl_rtl = crtl->return_rtx;
4715 /* This should be set in assign_parms. */
4716 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl));
4718 /* If this is a BLKmode structure being returned in registers,
4719 then use the mode computed in expand_return. Note that if
4720 decl_rtl is memory, then its mode may have been changed,
4721 but that crtl->return_rtx has not. */
4722 if (GET_MODE (real_decl_rtl) == BLKmode)
4723 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
4725 /* If a non-BLKmode return value should be padded at the least
4726 significant end of the register, shift it left by the appropriate
4727 amount. BLKmode results are handled using the group load/store
4729 if (TYPE_MODE (TREE_TYPE (decl_result)) != BLKmode
4730 && targetm.calls.return_in_msb (TREE_TYPE (decl_result)))
4732 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl),
4733 REGNO (real_decl_rtl)),
4735 shift_return_value (GET_MODE (decl_rtl), true, real_decl_rtl);
4737 /* If a named return value dumped decl_return to memory, then
4738 we may need to re-do the PROMOTE_MODE signed/unsigned
4740 else if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
4742 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (decl_result));
4743 promote_function_mode (TREE_TYPE (decl_result),
4744 GET_MODE (decl_rtl), &unsignedp,
4745 TREE_TYPE (current_function_decl), 1);
4747 convert_move (real_decl_rtl, decl_rtl, unsignedp);
4749 else if (GET_CODE (real_decl_rtl) == PARALLEL)
4751 /* If expand_function_start has created a PARALLEL for decl_rtl,
4752 move the result to the real return registers. Otherwise, do
4753 a group load from decl_rtl for a named return. */
4754 if (GET_CODE (decl_rtl) == PARALLEL)
4755 emit_group_move (real_decl_rtl, decl_rtl);
4757 emit_group_load (real_decl_rtl, decl_rtl,
4758 TREE_TYPE (decl_result),
4759 int_size_in_bytes (TREE_TYPE (decl_result)));
4761 /* In the case of complex integer modes smaller than a word, we'll
4762 need to generate some non-trivial bitfield insertions. Do that
4763 on a pseudo and not the hard register. */
4764 else if (GET_CODE (decl_rtl) == CONCAT
4765 && GET_MODE_CLASS (GET_MODE (decl_rtl)) == MODE_COMPLEX_INT
4766 && GET_MODE_BITSIZE (GET_MODE (decl_rtl)) <= BITS_PER_WORD)
4768 int old_generating_concat_p;
4771 old_generating_concat_p = generating_concat_p;
4772 generating_concat_p = 0;
4773 tmp = gen_reg_rtx (GET_MODE (decl_rtl));
4774 generating_concat_p = old_generating_concat_p;
4776 emit_move_insn (tmp, decl_rtl);
4777 emit_move_insn (real_decl_rtl, tmp);
4780 emit_move_insn (real_decl_rtl, decl_rtl);
4784 /* If returning a structure, arrange to return the address of the value
4785 in a place where debuggers expect to find it.
4787 If returning a structure PCC style,
4788 the caller also depends on this value.
4789 And cfun->returns_pcc_struct is not necessarily set. */
4790 if (cfun->returns_struct
4791 || cfun->returns_pcc_struct)
4793 rtx value_address = DECL_RTL (DECL_RESULT (current_function_decl));
4794 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
4797 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))
4798 type = TREE_TYPE (type);
4800 value_address = XEXP (value_address, 0);
4802 outgoing = targetm.calls.function_value (build_pointer_type (type),
4803 current_function_decl, true);
4805 /* Mark this as a function return value so integrate will delete the
4806 assignment and USE below when inlining this function. */
4807 REG_FUNCTION_VALUE_P (outgoing) = 1;
4809 /* The address may be ptr_mode and OUTGOING may be Pmode. */
4810 value_address = convert_memory_address (GET_MODE (outgoing),
4813 emit_move_insn (outgoing, value_address);
4815 /* Show return register used to hold result (in this case the address
4817 crtl->return_rtx = outgoing;
4820 /* Emit the actual code to clobber return register. */
4825 clobber_return_register ();
4829 emit_insn_after (seq, clobber_after);
4832 /* Output the label for the naked return from the function. */
4833 if (naked_return_label)
4834 emit_label (naked_return_label);
4836 /* @@@ This is a kludge. We want to ensure that instructions that
4837 may trap are not moved into the epilogue by scheduling, because
4838 we don't always emit unwind information for the epilogue. */
4839 if (! USING_SJLJ_EXCEPTIONS && flag_non_call_exceptions)
4840 emit_insn (gen_blockage ());
4842 /* If stack protection is enabled for this function, check the guard. */
4843 if (crtl->stack_protect_guard)
4844 stack_protect_epilogue ();
4846 /* If we had calls to alloca, and this machine needs
4847 an accurate stack pointer to exit the function,
4848 insert some code to save and restore the stack pointer. */
4849 if (! EXIT_IGNORE_STACK
4850 && cfun->calls_alloca)
4854 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
4855 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
4858 /* ??? This should no longer be necessary since stupid is no longer with
4859 us, but there are some parts of the compiler (eg reload_combine, and
4860 sh mach_dep_reorg) that still try and compute their own lifetime info
4861 instead of using the general framework. */
4862 use_return_register ();
4866 get_arg_pointer_save_area (void)
4868 rtx ret = arg_pointer_save_area;
4872 ret = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
4873 arg_pointer_save_area = ret;
4876 if (! crtl->arg_pointer_save_area_init)
4880 /* Save the arg pointer at the beginning of the function. The
4881 generated stack slot may not be a valid memory address, so we
4882 have to check it and fix it if necessary. */
4884 emit_move_insn (validize_mem (ret),
4885 crtl->args.internal_arg_pointer);
4889 push_topmost_sequence ();
4890 emit_insn_after (seq, entry_of_function ());
4891 pop_topmost_sequence ();
4897 /* Add a list of INSNS to the hash HASHP, possibly allocating HASHP
4898 for the first time. */
4901 record_insns (rtx insns, rtx end, htab_t *hashp)
4904 htab_t hash = *hashp;
4908 = htab_create_ggc (17, htab_hash_pointer, htab_eq_pointer, NULL);
4910 for (tmp = insns; tmp != end; tmp = NEXT_INSN (tmp))
4912 void **slot = htab_find_slot (hash, tmp, INSERT);
4913 gcc_assert (*slot == NULL);
4918 /* INSN has been duplicated as COPY, as part of duping a basic block.
4919 If INSN is an epilogue insn, then record COPY as epilogue as well. */
4922 maybe_copy_epilogue_insn (rtx insn, rtx copy)
4926 if (epilogue_insn_hash == NULL
4927 || htab_find (epilogue_insn_hash, insn) == NULL)
4930 slot = htab_find_slot (epilogue_insn_hash, copy, INSERT);
4931 gcc_assert (*slot == NULL);
4935 /* Set the locator of the insn chain starting at INSN to LOC. */
4937 set_insn_locators (rtx insn, int loc)
4939 while (insn != NULL_RTX)
4942 INSN_LOCATOR (insn) = loc;
4943 insn = NEXT_INSN (insn);
4947 /* Determine if any INSNs in HASH are, or are part of, INSN. Because
4948 we can be running after reorg, SEQUENCE rtl is possible. */
4951 contains (const_rtx insn, htab_t hash)
4956 if (NONJUMP_INSN_P (insn) && GET_CODE (PATTERN (insn)) == SEQUENCE)
4959 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
4960 if (htab_find (hash, XVECEXP (PATTERN (insn), 0, i)))
4965 return htab_find (hash, insn) != NULL;
4969 prologue_epilogue_contains (const_rtx insn)
4971 if (contains (insn, prologue_insn_hash))
4973 if (contains (insn, epilogue_insn_hash))
4979 /* Insert gen_return at the end of block BB. This also means updating
4980 block_for_insn appropriately. */
4983 emit_return_into_block (basic_block bb)
4985 emit_jump_insn_after (gen_return (), BB_END (bb));
4987 #endif /* HAVE_return */
4989 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
4990 this into place with notes indicating where the prologue ends and where
4991 the epilogue begins. Update the basic block information when possible. */
4994 thread_prologue_and_epilogue_insns (void)
4998 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
5001 #if defined (HAVE_epilogue) || defined(HAVE_return)
5002 rtx epilogue_end = NULL_RTX;
5006 rtl_profile_for_bb (ENTRY_BLOCK_PTR);
5007 #ifdef HAVE_prologue
5011 seq = gen_prologue ();
5014 /* Insert an explicit USE for the frame pointer
5015 if the profiling is on and the frame pointer is required. */
5016 if (crtl->profile && frame_pointer_needed)
5017 emit_use (hard_frame_pointer_rtx);
5019 /* Retain a map of the prologue insns. */
5020 record_insns (seq, NULL, &prologue_insn_hash);
5021 emit_note (NOTE_INSN_PROLOGUE_END);
5023 #ifndef PROFILE_BEFORE_PROLOGUE
5024 /* Ensure that instructions are not moved into the prologue when
5025 profiling is on. The call to the profiling routine can be
5026 emitted within the live range of a call-clobbered register. */
5028 emit_insn (gen_blockage ());
5033 set_insn_locators (seq, prologue_locator);
5035 /* Can't deal with multiple successors of the entry block
5036 at the moment. Function should always have at least one
5038 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR));
5040 insert_insn_on_edge (seq, single_succ_edge (ENTRY_BLOCK_PTR));
5045 /* If the exit block has no non-fake predecessors, we don't need
5047 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5048 if ((e->flags & EDGE_FAKE) == 0)
5053 rtl_profile_for_bb (EXIT_BLOCK_PTR);
5055 if (optimize && HAVE_return)
5057 /* If we're allowed to generate a simple return instruction,
5058 then by definition we don't need a full epilogue. Examine
5059 the block that falls through to EXIT. If it does not
5060 contain any code, examine its predecessors and try to
5061 emit (conditional) return instructions. */
5066 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5067 if (e->flags & EDGE_FALLTHRU)
5073 /* Verify that there are no active instructions in the last block. */
5074 label = BB_END (last);
5075 while (label && !LABEL_P (label))
5077 if (active_insn_p (label))
5079 label = PREV_INSN (label);
5082 if (BB_HEAD (last) == label && LABEL_P (label))
5086 for (ei2 = ei_start (last->preds); (e = ei_safe_edge (ei2)); )
5088 basic_block bb = e->src;
5091 if (bb == ENTRY_BLOCK_PTR)
5098 if (!JUMP_P (jump) || JUMP_LABEL (jump) != label)
5104 /* If we have an unconditional jump, we can replace that
5105 with a simple return instruction. */
5106 if (simplejump_p (jump))
5108 emit_return_into_block (bb);
5112 /* If we have a conditional jump, we can try to replace
5113 that with a conditional return instruction. */
5114 else if (condjump_p (jump))
5116 if (! redirect_jump (jump, 0, 0))
5122 /* If this block has only one successor, it both jumps
5123 and falls through to the fallthru block, so we can't
5125 if (single_succ_p (bb))
5137 /* Fix up the CFG for the successful change we just made. */
5138 redirect_edge_succ (e, EXIT_BLOCK_PTR);
5141 /* Emit a return insn for the exit fallthru block. Whether
5142 this is still reachable will be determined later. */
5144 emit_barrier_after (BB_END (last));
5145 emit_return_into_block (last);
5146 epilogue_end = BB_END (last);
5147 single_succ_edge (last)->flags &= ~EDGE_FALLTHRU;
5153 /* A small fib -- epilogue is not yet completed, but we wish to re-use
5154 this marker for the splits of EH_RETURN patterns, and nothing else
5155 uses the flag in the meantime. */
5156 epilogue_completed = 1;
5158 #ifdef HAVE_eh_return
5159 /* Find non-fallthru edges that end with EH_RETURN instructions. On
5160 some targets, these get split to a special version of the epilogue
5161 code. In order to be able to properly annotate these with unwind
5162 info, try to split them now. If we get a valid split, drop an
5163 EPILOGUE_BEG note and mark the insns as epilogue insns. */
5164 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5166 rtx prev, last, trial;
5168 if (e->flags & EDGE_FALLTHRU)
5170 last = BB_END (e->src);
5171 if (!eh_returnjump_p (last))
5174 prev = PREV_INSN (last);
5175 trial = try_split (PATTERN (last), last, 1);
5179 record_insns (NEXT_INSN (prev), NEXT_INSN (trial), &epilogue_insn_hash);
5180 emit_note_after (NOTE_INSN_EPILOGUE_BEG, prev);
5184 /* Find the edge that falls through to EXIT. Other edges may exist
5185 due to RETURN instructions, but those don't need epilogues.
5186 There really shouldn't be a mixture -- either all should have
5187 been converted or none, however... */
5189 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5190 if (e->flags & EDGE_FALLTHRU)
5195 #ifdef HAVE_epilogue
5199 epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG);
5200 seq = gen_epilogue ();
5201 emit_jump_insn (seq);
5203 /* Retain a map of the epilogue insns. */
5204 record_insns (seq, NULL, &epilogue_insn_hash);
5205 set_insn_locators (seq, epilogue_locator);
5210 insert_insn_on_edge (seq, e);
5218 if (! next_active_insn (BB_END (e->src)))
5220 /* We have a fall-through edge to the exit block, the source is not
5221 at the end of the function, and there will be an assembler epilogue
5222 at the end of the function.
5223 We can't use force_nonfallthru here, because that would try to
5224 use return. Inserting a jump 'by hand' is extremely messy, so
5225 we take advantage of cfg_layout_finalize using
5226 fixup_fallthru_exit_predecessor. */
5227 cfg_layout_initialize (0);
5228 FOR_EACH_BB (cur_bb)
5229 if (cur_bb->index >= NUM_FIXED_BLOCKS
5230 && cur_bb->next_bb->index >= NUM_FIXED_BLOCKS)
5231 cur_bb->aux = cur_bb->next_bb;
5232 cfg_layout_finalize ();
5235 default_rtl_profile ();
5239 commit_edge_insertions ();
5241 /* The epilogue insns we inserted may cause the exit edge to no longer
5243 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5245 if (((e->flags & EDGE_FALLTHRU) != 0)
5246 && returnjump_p (BB_END (e->src)))
5247 e->flags &= ~EDGE_FALLTHRU;
5251 #ifdef HAVE_sibcall_epilogue
5252 /* Emit sibling epilogues before any sibling call sites. */
5253 for (ei = ei_start (EXIT_BLOCK_PTR->preds); (e = ei_safe_edge (ei)); )
5255 basic_block bb = e->src;
5256 rtx insn = BB_END (bb);
5259 || ! SIBLING_CALL_P (insn))
5266 emit_note (NOTE_INSN_EPILOGUE_BEG);
5267 emit_insn (gen_sibcall_epilogue ());
5271 /* Retain a map of the epilogue insns. Used in life analysis to
5272 avoid getting rid of sibcall epilogue insns. Do this before we
5273 actually emit the sequence. */
5274 record_insns (seq, NULL, &epilogue_insn_hash);
5275 set_insn_locators (seq, epilogue_locator);
5277 emit_insn_before (seq, insn);
5282 #ifdef HAVE_epilogue
5287 /* Similarly, move any line notes that appear after the epilogue.
5288 There is no need, however, to be quite so anal about the existence
5289 of such a note. Also possibly move
5290 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
5292 for (insn = epilogue_end; insn; insn = next)
5294 next = NEXT_INSN (insn);
5296 && (NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG))
5297 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
5302 /* Threading the prologue and epilogue changes the artificial refs
5303 in the entry and exit blocks. */
5304 epilogue_completed = 1;
5305 df_update_entry_exit_and_calls ();
5308 /* Reposition the prologue-end and epilogue-begin notes after
5309 instruction scheduling. */
5312 reposition_prologue_and_epilogue_notes (void)
5314 #if defined (HAVE_prologue) || defined (HAVE_epilogue) \
5315 || defined (HAVE_sibcall_epilogue)
5316 /* Since the hash table is created on demand, the fact that it is
5317 non-null is a signal that it is non-empty. */
5318 if (prologue_insn_hash != NULL)
5320 size_t len = htab_elements (prologue_insn_hash);
5321 rtx insn, last = NULL, note = NULL;
5323 /* Scan from the beginning until we reach the last prologue insn. */
5324 /* ??? While we do have the CFG intact, there are two problems:
5325 (1) The prologue can contain loops (typically probing the stack),
5326 which means that the end of the prologue isn't in the first bb.
5327 (2) Sometimes the PROLOGUE_END note gets pushed into the next bb. */
5328 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
5332 if (NOTE_KIND (insn) == NOTE_INSN_PROLOGUE_END)
5335 else if (contains (insn, prologue_insn_hash))
5347 /* Scan forward looking for the PROLOGUE_END note. It should
5348 be right at the beginning of the block, possibly with other
5349 insn notes that got moved there. */
5350 for (note = NEXT_INSN (last); ; note = NEXT_INSN (note))
5353 && NOTE_KIND (note) == NOTE_INSN_PROLOGUE_END)
5358 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
5360 last = NEXT_INSN (last);
5361 reorder_insns (note, note, last);
5365 if (epilogue_insn_hash != NULL)
5370 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5372 rtx insn, first = NULL, note = NULL;
5373 basic_block bb = e->src;
5375 /* Scan from the beginning until we reach the first epilogue insn. */
5376 FOR_BB_INSNS (bb, insn)
5380 if (NOTE_KIND (insn) == NOTE_INSN_EPILOGUE_BEG)
5387 else if (first == NULL && contains (insn, epilogue_insn_hash))
5397 /* If the function has a single basic block, and no real
5398 epilogue insns (e.g. sibcall with no cleanup), the
5399 epilogue note can get scheduled before the prologue
5400 note. If we have frame related prologue insns, having
5401 them scanned during the epilogue will result in a crash.
5402 In this case re-order the epilogue note to just before
5403 the last insn in the block. */
5405 first = BB_END (bb);
5407 if (PREV_INSN (first) != note)
5408 reorder_insns (note, note, PREV_INSN (first));
5412 #endif /* HAVE_prologue or HAVE_epilogue */
5415 /* Returns the name of the current function. */
5417 current_function_name (void)
5421 return lang_hooks.decl_printable_name (cfun->decl, 2);
5426 rest_of_handle_check_leaf_regs (void)
5428 #ifdef LEAF_REGISTERS
5429 current_function_uses_only_leaf_regs
5430 = optimize > 0 && only_leaf_regs_used () && leaf_function_p ();
5435 /* Insert a TYPE into the used types hash table of CFUN. */
5438 used_types_insert_helper (tree type, struct function *func)
5440 if (type != NULL && func != NULL)
5444 if (func->used_types_hash == NULL)
5445 func->used_types_hash = htab_create_ggc (37, htab_hash_pointer,
5446 htab_eq_pointer, NULL);
5447 slot = htab_find_slot (func->used_types_hash, type, INSERT);
5453 /* Given a type, insert it into the used hash table in cfun. */
5455 used_types_insert (tree t)
5457 while (POINTER_TYPE_P (t) || TREE_CODE (t) == ARRAY_TYPE)
5459 t = TYPE_MAIN_VARIANT (t);
5460 if (debug_info_level > DINFO_LEVEL_NONE)
5463 used_types_insert_helper (t, cfun);
5465 /* So this might be a type referenced by a global variable.
5466 Record that type so that we can later decide to emit its debug
5468 types_used_by_cur_var_decl =
5469 tree_cons (t, NULL, types_used_by_cur_var_decl);
5474 /* Helper to Hash a struct types_used_by_vars_entry. */
5477 hash_types_used_by_vars_entry (const struct types_used_by_vars_entry *entry)
5479 gcc_assert (entry && entry->var_decl && entry->type);
5481 return iterative_hash_object (entry->type,
5482 iterative_hash_object (entry->var_decl, 0));
5485 /* Hash function of the types_used_by_vars_entry hash table. */
5488 types_used_by_vars_do_hash (const void *x)
5490 const struct types_used_by_vars_entry *entry =
5491 (const struct types_used_by_vars_entry *) x;
5493 return hash_types_used_by_vars_entry (entry);
5496 /*Equality function of the types_used_by_vars_entry hash table. */
5499 types_used_by_vars_eq (const void *x1, const void *x2)
5501 const struct types_used_by_vars_entry *e1 =
5502 (const struct types_used_by_vars_entry *) x1;
5503 const struct types_used_by_vars_entry *e2 =
5504 (const struct types_used_by_vars_entry *)x2;
5506 return (e1->var_decl == e2->var_decl && e1->type == e2->type);
5509 /* Inserts an entry into the types_used_by_vars_hash hash table. */
5512 types_used_by_var_decl_insert (tree type, tree var_decl)
5514 if (type != NULL && var_decl != NULL)
5517 struct types_used_by_vars_entry e;
5518 e.var_decl = var_decl;
5520 if (types_used_by_vars_hash == NULL)
5521 types_used_by_vars_hash =
5522 htab_create_ggc (37, types_used_by_vars_do_hash,
5523 types_used_by_vars_eq, NULL);
5524 slot = htab_find_slot_with_hash (types_used_by_vars_hash, &e,
5525 hash_types_used_by_vars_entry (&e), INSERT);
5528 struct types_used_by_vars_entry *entry;
5529 entry = (struct types_used_by_vars_entry*) ggc_alloc
5530 (sizeof (struct types_used_by_vars_entry));
5532 entry->var_decl = var_decl;
5538 struct rtl_opt_pass pass_leaf_regs =
5542 "*leaf_regs", /* name */
5544 rest_of_handle_check_leaf_regs, /* execute */
5547 0, /* static_pass_number */
5548 TV_NONE, /* tv_id */
5549 0, /* properties_required */
5550 0, /* properties_provided */
5551 0, /* properties_destroyed */
5552 0, /* todo_flags_start */
5553 0 /* todo_flags_finish */
5558 rest_of_handle_thread_prologue_and_epilogue (void)
5561 cleanup_cfg (CLEANUP_EXPENSIVE);
5562 /* On some machines, the prologue and epilogue code, or parts thereof,
5563 can be represented as RTL. Doing so lets us schedule insns between
5564 it and the rest of the code and also allows delayed branch
5565 scheduling to operate in the epilogue. */
5567 thread_prologue_and_epilogue_insns ();
5571 struct rtl_opt_pass pass_thread_prologue_and_epilogue =
5575 "pro_and_epilogue", /* name */
5577 rest_of_handle_thread_prologue_and_epilogue, /* execute */
5580 0, /* static_pass_number */
5581 TV_THREAD_PROLOGUE_AND_EPILOGUE, /* tv_id */
5582 0, /* properties_required */
5583 0, /* properties_provided */
5584 0, /* properties_destroyed */
5585 TODO_verify_flow, /* todo_flags_start */
5588 TODO_df_finish | TODO_verify_rtl_sharing |
5589 TODO_ggc_collect /* todo_flags_finish */
5594 /* This mini-pass fixes fall-out from SSA in asm statements that have
5595 in-out constraints. Say you start with
5598 asm ("": "+mr" (inout));
5601 which is transformed very early to use explicit output and match operands:
5604 asm ("": "=mr" (inout) : "0" (inout));
5607 Or, after SSA and copyprop,
5609 asm ("": "=mr" (inout_2) : "0" (inout_1));
5612 Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
5613 they represent two separate values, so they will get different pseudo
5614 registers during expansion. Then, since the two operands need to match
5615 per the constraints, but use different pseudo registers, reload can
5616 only register a reload for these operands. But reloads can only be
5617 satisfied by hardregs, not by memory, so we need a register for this
5618 reload, just because we are presented with non-matching operands.
5619 So, even though we allow memory for this operand, no memory can be
5620 used for it, just because the two operands don't match. This can
5621 cause reload failures on register-starved targets.
5623 So it's a symptom of reload not being able to use memory for reloads
5624 or, alternatively it's also a symptom of both operands not coming into
5625 reload as matching (in which case the pseudo could go to memory just
5626 fine, as the alternative allows it, and no reload would be necessary).
5627 We fix the latter problem here, by transforming
5629 asm ("": "=mr" (inout_2) : "0" (inout_1));
5634 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
5637 match_asm_constraints_1 (rtx insn, rtx *p_sets, int noutputs)
5640 bool changed = false;
5641 rtx op = SET_SRC (p_sets[0]);
5642 int ninputs = ASM_OPERANDS_INPUT_LENGTH (op);
5643 rtvec inputs = ASM_OPERANDS_INPUT_VEC (op);
5644 bool *output_matched = XALLOCAVEC (bool, noutputs);
5646 memset (output_matched, 0, noutputs * sizeof (bool));
5647 for (i = 0; i < ninputs; i++)
5649 rtx input, output, insns;
5650 const char *constraint = ASM_OPERANDS_INPUT_CONSTRAINT (op, i);
5654 if (*constraint == '%')
5657 match = strtoul (constraint, &end, 10);
5658 if (end == constraint)
5661 gcc_assert (match < noutputs);
5662 output = SET_DEST (p_sets[match]);
5663 input = RTVEC_ELT (inputs, i);
5664 /* Only do the transformation for pseudos. */
5665 if (! REG_P (output)
5666 || rtx_equal_p (output, input)
5667 || (GET_MODE (input) != VOIDmode
5668 && GET_MODE (input) != GET_MODE (output)))
5671 /* We can't do anything if the output is also used as input,
5672 as we're going to overwrite it. */
5673 for (j = 0; j < ninputs; j++)
5674 if (reg_overlap_mentioned_p (output, RTVEC_ELT (inputs, j)))
5679 /* Avoid changing the same input several times. For
5680 asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
5681 only change in once (to out1), rather than changing it
5682 first to out1 and afterwards to out2. */
5685 for (j = 0; j < noutputs; j++)
5686 if (output_matched[j] && input == SET_DEST (p_sets[j]))
5691 output_matched[match] = true;
5694 emit_move_insn (output, input);
5695 insns = get_insns ();
5697 emit_insn_before (insns, insn);
5699 /* Now replace all mentions of the input with output. We can't
5700 just replace the occurrence in inputs[i], as the register might
5701 also be used in some other input (or even in an address of an
5702 output), which would mean possibly increasing the number of
5703 inputs by one (namely 'output' in addition), which might pose
5704 a too complicated problem for reload to solve. E.g. this situation:
5706 asm ("" : "=r" (output), "=m" (input) : "0" (input))
5708 Here 'input' is used in two occurrences as input (once for the
5709 input operand, once for the address in the second output operand).
5710 If we would replace only the occurrence of the input operand (to
5711 make the matching) we would be left with this:
5714 asm ("" : "=r" (output), "=m" (input) : "0" (output))
5716 Now we suddenly have two different input values (containing the same
5717 value, but different pseudos) where we formerly had only one.
5718 With more complicated asms this might lead to reload failures
5719 which wouldn't have happen without this pass. So, iterate over
5720 all operands and replace all occurrences of the register used. */
5721 for (j = 0; j < noutputs; j++)
5722 if (!rtx_equal_p (SET_DEST (p_sets[j]), input)
5723 && reg_overlap_mentioned_p (input, SET_DEST (p_sets[j])))
5724 SET_DEST (p_sets[j]) = replace_rtx (SET_DEST (p_sets[j]),
5726 for (j = 0; j < ninputs; j++)
5727 if (reg_overlap_mentioned_p (input, RTVEC_ELT (inputs, j)))
5728 RTVEC_ELT (inputs, j) = replace_rtx (RTVEC_ELT (inputs, j),
5735 df_insn_rescan (insn);
5739 rest_of_match_asm_constraints (void)
5742 rtx insn, pat, *p_sets;
5745 if (!crtl->has_asm_statement)
5748 df_set_flags (DF_DEFER_INSN_RESCAN);
5751 FOR_BB_INSNS (bb, insn)
5756 pat = PATTERN (insn);
5757 if (GET_CODE (pat) == PARALLEL)
5758 p_sets = &XVECEXP (pat, 0, 0), noutputs = XVECLEN (pat, 0);
5759 else if (GET_CODE (pat) == SET)
5760 p_sets = &PATTERN (insn), noutputs = 1;
5764 if (GET_CODE (*p_sets) == SET
5765 && GET_CODE (SET_SRC (*p_sets)) == ASM_OPERANDS)
5766 match_asm_constraints_1 (insn, p_sets, noutputs);
5770 return TODO_df_finish;
5773 struct rtl_opt_pass pass_match_asm_constraints =
5777 "asmcons", /* name */
5779 rest_of_match_asm_constraints, /* execute */
5782 0, /* static_pass_number */
5783 TV_NONE, /* tv_id */
5784 0, /* properties_required */
5785 0, /* properties_provided */
5786 0, /* properties_destroyed */
5787 0, /* todo_flags_start */
5788 TODO_dump_func /* todo_flags_finish */
5793 #include "gt-function.h"