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 2010, 2011 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"
40 #include "rtl-error.h"
49 #include "hard-reg-set.h"
50 #include "insn-config.h"
53 #include "basic-block.h"
57 #include "integrate.h"
58 #include "langhooks.h"
60 #include "common/common-target.h"
61 #include "cfglayout.h"
63 #include "tree-pass.h"
69 #include "bb-reorder.h"
71 /* So we can assign to cfun in this file. */
74 #ifndef STACK_ALIGNMENT_NEEDED
75 #define STACK_ALIGNMENT_NEEDED 1
78 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
80 /* Some systems use __main in a way incompatible with its use in gcc, in these
81 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
82 give the same symbol without quotes for an alternative entry point. You
83 must define both, or neither. */
85 #define NAME__MAIN "__main"
88 /* Round a value to the lowest integer less than it that is a multiple of
89 the required alignment. Avoid using division in case the value is
90 negative. Assume the alignment is a power of two. */
91 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
93 /* Similar, but round to the next highest integer that meets the
95 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
97 /* Nonzero if function being compiled doesn't contain any calls
98 (ignoring the prologue and epilogue). This is set prior to
99 local register allocation and is valid for the remaining
101 int current_function_is_leaf;
103 /* Nonzero if function being compiled doesn't modify the stack pointer
104 (ignoring the prologue and epilogue). This is only valid after
105 pass_stack_ptr_mod has run. */
106 int current_function_sp_is_unchanging;
108 /* Nonzero if the function being compiled is a leaf function which only
109 uses leaf registers. This is valid after reload (specifically after
110 sched2) and is useful only if the port defines LEAF_REGISTERS. */
111 int current_function_uses_only_leaf_regs;
113 /* Nonzero once virtual register instantiation has been done.
114 assign_stack_local uses frame_pointer_rtx when this is nonzero.
115 calls.c:emit_library_call_value_1 uses it to set up
116 post-instantiation libcalls. */
117 int virtuals_instantiated;
119 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
120 static GTY(()) int funcdef_no;
122 /* These variables hold pointers to functions to create and destroy
123 target specific, per-function data structures. */
124 struct machine_function * (*init_machine_status) (void);
126 /* The currently compiled function. */
127 struct function *cfun = 0;
129 /* These hashes record the prologue and epilogue insns. */
130 static GTY((if_marked ("ggc_marked_p"), param_is (struct rtx_def)))
131 htab_t prologue_insn_hash;
132 static GTY((if_marked ("ggc_marked_p"), param_is (struct rtx_def)))
133 htab_t epilogue_insn_hash;
136 htab_t types_used_by_vars_hash = NULL;
137 VEC(tree,gc) *types_used_by_cur_var_decl;
139 /* Forward declarations. */
141 static struct temp_slot *find_temp_slot_from_address (rtx);
142 static void pad_to_arg_alignment (struct args_size *, int, struct args_size *);
143 static void pad_below (struct args_size *, enum machine_mode, tree);
144 static void reorder_blocks_1 (rtx, tree, VEC(tree,heap) **);
145 static int all_blocks (tree, tree *);
146 static tree *get_block_vector (tree, int *);
147 extern tree debug_find_var_in_block_tree (tree, tree);
148 /* We always define `record_insns' even if it's not used so that we
149 can always export `prologue_epilogue_contains'. */
150 static void record_insns (rtx, rtx, htab_t *) ATTRIBUTE_UNUSED;
151 static bool contains (const_rtx, htab_t);
152 static void prepare_function_start (void);
153 static void do_clobber_return_reg (rtx, void *);
154 static void do_use_return_reg (rtx, void *);
155 static void set_insn_locators (rtx, int) ATTRIBUTE_UNUSED;
157 /* Stack of nested functions. */
158 /* Keep track of the cfun stack. */
160 typedef struct function *function_p;
162 DEF_VEC_P(function_p);
163 DEF_VEC_ALLOC_P(function_p,heap);
164 static VEC(function_p,heap) *function_context_stack;
166 /* Save the current context for compilation of a nested function.
167 This is called from language-specific code. */
170 push_function_context (void)
173 allocate_struct_function (NULL, false);
175 VEC_safe_push (function_p, heap, function_context_stack, cfun);
179 /* Restore the last saved context, at the end of a nested function.
180 This function is called from language-specific code. */
183 pop_function_context (void)
185 struct function *p = VEC_pop (function_p, function_context_stack);
187 current_function_decl = p->decl;
189 /* Reset variables that have known state during rtx generation. */
190 virtuals_instantiated = 0;
191 generating_concat_p = 1;
194 /* Clear out all parts of the state in F that can safely be discarded
195 after the function has been parsed, but not compiled, to let
196 garbage collection reclaim the memory. */
199 free_after_parsing (struct function *f)
204 /* Clear out all parts of the state in F that can safely be discarded
205 after the function has been compiled, to let garbage collection
206 reclaim the memory. */
209 free_after_compilation (struct function *f)
211 prologue_insn_hash = NULL;
212 epilogue_insn_hash = NULL;
214 free (crtl->emit.regno_pointer_align);
216 memset (crtl, 0, sizeof (struct rtl_data));
221 regno_reg_rtx = NULL;
222 insn_locators_free ();
225 /* Return size needed for stack frame based on slots so far allocated.
226 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
227 the caller may have to do that. */
230 get_frame_size (void)
232 if (FRAME_GROWS_DOWNWARD)
233 return -frame_offset;
238 /* Issue an error message and return TRUE if frame OFFSET overflows in
239 the signed target pointer arithmetics for function FUNC. Otherwise
243 frame_offset_overflow (HOST_WIDE_INT offset, tree func)
245 unsigned HOST_WIDE_INT size = FRAME_GROWS_DOWNWARD ? -offset : offset;
247 if (size > ((unsigned HOST_WIDE_INT) 1 << (GET_MODE_BITSIZE (Pmode) - 1))
248 /* Leave room for the fixed part of the frame. */
249 - 64 * UNITS_PER_WORD)
251 error_at (DECL_SOURCE_LOCATION (func),
252 "total size of local objects too large");
259 /* Return stack slot alignment in bits for TYPE and MODE. */
262 get_stack_local_alignment (tree type, enum machine_mode mode)
264 unsigned int alignment;
267 alignment = BIGGEST_ALIGNMENT;
269 alignment = GET_MODE_ALIGNMENT (mode);
271 /* Allow the frond-end to (possibly) increase the alignment of this
274 type = lang_hooks.types.type_for_mode (mode, 0);
276 return STACK_SLOT_ALIGNMENT (type, mode, alignment);
279 /* Determine whether it is possible to fit a stack slot of size SIZE and
280 alignment ALIGNMENT into an area in the stack frame that starts at
281 frame offset START and has a length of LENGTH. If so, store the frame
282 offset to be used for the stack slot in *POFFSET and return true;
283 return false otherwise. This function will extend the frame size when
284 given a start/length pair that lies at the end of the frame. */
287 try_fit_stack_local (HOST_WIDE_INT start, HOST_WIDE_INT length,
288 HOST_WIDE_INT size, unsigned int alignment,
289 HOST_WIDE_INT *poffset)
291 HOST_WIDE_INT this_frame_offset;
292 int frame_off, frame_alignment, frame_phase;
294 /* Calculate how many bytes the start of local variables is off from
296 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
297 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
298 frame_phase = frame_off ? frame_alignment - frame_off : 0;
300 /* Round the frame offset to the specified alignment. */
302 /* We must be careful here, since FRAME_OFFSET might be negative and
303 division with a negative dividend isn't as well defined as we might
304 like. So we instead assume that ALIGNMENT is a power of two and
305 use logical operations which are unambiguous. */
306 if (FRAME_GROWS_DOWNWARD)
308 = (FLOOR_ROUND (start + length - size - frame_phase,
309 (unsigned HOST_WIDE_INT) alignment)
313 = (CEIL_ROUND (start - frame_phase,
314 (unsigned HOST_WIDE_INT) alignment)
317 /* See if it fits. If this space is at the edge of the frame,
318 consider extending the frame to make it fit. Our caller relies on
319 this when allocating a new slot. */
320 if (frame_offset == start && this_frame_offset < frame_offset)
321 frame_offset = this_frame_offset;
322 else if (this_frame_offset < start)
324 else if (start + length == frame_offset
325 && this_frame_offset + size > start + length)
326 frame_offset = this_frame_offset + size;
327 else if (this_frame_offset + size > start + length)
330 *poffset = this_frame_offset;
334 /* Create a new frame_space structure describing free space in the stack
335 frame beginning at START and ending at END, and chain it into the
336 function's frame_space_list. */
339 add_frame_space (HOST_WIDE_INT start, HOST_WIDE_INT end)
341 struct frame_space *space = ggc_alloc_frame_space ();
342 space->next = crtl->frame_space_list;
343 crtl->frame_space_list = space;
344 space->start = start;
345 space->length = end - start;
348 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
349 with machine mode MODE.
351 ALIGN controls the amount of alignment for the address of the slot:
352 0 means according to MODE,
353 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
354 -2 means use BITS_PER_UNIT,
355 positive specifies alignment boundary in bits.
357 KIND has ASLK_REDUCE_ALIGN bit set if it is OK to reduce
358 alignment and ASLK_RECORD_PAD bit set if we should remember
359 extra space we allocated for alignment purposes. When we are
360 called from assign_stack_temp_for_type, it is not set so we don't
361 track the same stack slot in two independent lists.
363 We do not round to stack_boundary here. */
366 assign_stack_local_1 (enum machine_mode mode, HOST_WIDE_INT size,
370 int bigend_correction = 0;
371 HOST_WIDE_INT slot_offset = 0, old_frame_offset;
372 unsigned int alignment, alignment_in_bits;
376 alignment = get_stack_local_alignment (NULL, mode);
377 alignment /= BITS_PER_UNIT;
379 else if (align == -1)
381 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
382 size = CEIL_ROUND (size, alignment);
384 else if (align == -2)
385 alignment = 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
387 alignment = align / BITS_PER_UNIT;
389 alignment_in_bits = alignment * BITS_PER_UNIT;
391 /* Ignore alignment if it exceeds MAX_SUPPORTED_STACK_ALIGNMENT. */
392 if (alignment_in_bits > MAX_SUPPORTED_STACK_ALIGNMENT)
394 alignment_in_bits = MAX_SUPPORTED_STACK_ALIGNMENT;
395 alignment = alignment_in_bits / BITS_PER_UNIT;
398 if (SUPPORTS_STACK_ALIGNMENT)
400 if (crtl->stack_alignment_estimated < alignment_in_bits)
402 if (!crtl->stack_realign_processed)
403 crtl->stack_alignment_estimated = alignment_in_bits;
406 /* If stack is realigned and stack alignment value
407 hasn't been finalized, it is OK not to increase
408 stack_alignment_estimated. The bigger alignment
409 requirement is recorded in stack_alignment_needed
411 gcc_assert (!crtl->stack_realign_finalized);
412 if (!crtl->stack_realign_needed)
414 /* It is OK to reduce the alignment as long as the
415 requested size is 0 or the estimated stack
416 alignment >= mode alignment. */
417 gcc_assert ((kind & ASLK_REDUCE_ALIGN)
419 || (crtl->stack_alignment_estimated
420 >= GET_MODE_ALIGNMENT (mode)));
421 alignment_in_bits = crtl->stack_alignment_estimated;
422 alignment = alignment_in_bits / BITS_PER_UNIT;
428 if (crtl->stack_alignment_needed < alignment_in_bits)
429 crtl->stack_alignment_needed = alignment_in_bits;
430 if (crtl->max_used_stack_slot_alignment < alignment_in_bits)
431 crtl->max_used_stack_slot_alignment = alignment_in_bits;
433 if (mode != BLKmode || size != 0)
435 if (kind & ASLK_RECORD_PAD)
437 struct frame_space **psp;
439 for (psp = &crtl->frame_space_list; *psp; psp = &(*psp)->next)
441 struct frame_space *space = *psp;
442 if (!try_fit_stack_local (space->start, space->length, size,
443 alignment, &slot_offset))
446 if (slot_offset > space->start)
447 add_frame_space (space->start, slot_offset);
448 if (slot_offset + size < space->start + space->length)
449 add_frame_space (slot_offset + size,
450 space->start + space->length);
455 else if (!STACK_ALIGNMENT_NEEDED)
457 slot_offset = frame_offset;
461 old_frame_offset = frame_offset;
463 if (FRAME_GROWS_DOWNWARD)
465 frame_offset -= size;
466 try_fit_stack_local (frame_offset, size, size, alignment, &slot_offset);
468 if (kind & ASLK_RECORD_PAD)
470 if (slot_offset > frame_offset)
471 add_frame_space (frame_offset, slot_offset);
472 if (slot_offset + size < old_frame_offset)
473 add_frame_space (slot_offset + size, old_frame_offset);
478 frame_offset += size;
479 try_fit_stack_local (old_frame_offset, size, size, alignment, &slot_offset);
481 if (kind & ASLK_RECORD_PAD)
483 if (slot_offset > old_frame_offset)
484 add_frame_space (old_frame_offset, slot_offset);
485 if (slot_offset + size < frame_offset)
486 add_frame_space (slot_offset + size, frame_offset);
491 /* On a big-endian machine, if we are allocating more space than we will use,
492 use the least significant bytes of those that are allocated. */
493 if (BYTES_BIG_ENDIAN && mode != BLKmode && GET_MODE_SIZE (mode) < size)
494 bigend_correction = size - GET_MODE_SIZE (mode);
496 /* If we have already instantiated virtual registers, return the actual
497 address relative to the frame pointer. */
498 if (virtuals_instantiated)
499 addr = plus_constant (frame_pointer_rtx,
501 (slot_offset + bigend_correction
502 + STARTING_FRAME_OFFSET, Pmode));
504 addr = plus_constant (virtual_stack_vars_rtx,
506 (slot_offset + bigend_correction,
509 x = gen_rtx_MEM (mode, addr);
510 set_mem_align (x, alignment_in_bits);
511 MEM_NOTRAP_P (x) = 1;
514 = gen_rtx_EXPR_LIST (VOIDmode, x, stack_slot_list);
516 if (frame_offset_overflow (frame_offset, current_function_decl))
522 /* Wrap up assign_stack_local_1 with last parameter as false. */
525 assign_stack_local (enum machine_mode mode, HOST_WIDE_INT size, int align)
527 return assign_stack_local_1 (mode, size, align, ASLK_RECORD_PAD);
531 /* In order to evaluate some expressions, such as function calls returning
532 structures in memory, we need to temporarily allocate stack locations.
533 We record each allocated temporary in the following structure.
535 Associated with each temporary slot is a nesting level. When we pop up
536 one level, all temporaries associated with the previous level are freed.
537 Normally, all temporaries are freed after the execution of the statement
538 in which they were created. However, if we are inside a ({...}) grouping,
539 the result may be in a temporary and hence must be preserved. If the
540 result could be in a temporary, we preserve it if we can determine which
541 one it is in. If we cannot determine which temporary may contain the
542 result, all temporaries are preserved. A temporary is preserved by
543 pretending it was allocated at the previous nesting level.
545 Automatic variables are also assigned temporary slots, at the nesting
546 level where they are defined. They are marked a "kept" so that
547 free_temp_slots will not free them. */
549 struct GTY(()) temp_slot {
550 /* Points to next temporary slot. */
551 struct temp_slot *next;
552 /* Points to previous temporary slot. */
553 struct temp_slot *prev;
554 /* The rtx to used to reference the slot. */
556 /* The size, in units, of the slot. */
558 /* The type of the object in the slot, or zero if it doesn't correspond
559 to a type. We use this to determine whether a slot can be reused.
560 It can be reused if objects of the type of the new slot will always
561 conflict with objects of the type of the old slot. */
563 /* The alignment (in bits) of the slot. */
565 /* Nonzero if this temporary is currently in use. */
567 /* Nonzero if this temporary has its address taken. */
569 /* Nesting level at which this slot is being used. */
571 /* Nonzero if this should survive a call to free_temp_slots. */
573 /* The offset of the slot from the frame_pointer, including extra space
574 for alignment. This info is for combine_temp_slots. */
575 HOST_WIDE_INT base_offset;
576 /* The size of the slot, including extra space for alignment. This
577 info is for combine_temp_slots. */
578 HOST_WIDE_INT full_size;
581 /* A table of addresses that represent a stack slot. The table is a mapping
582 from address RTXen to a temp slot. */
583 static GTY((param_is(struct temp_slot_address_entry))) htab_t temp_slot_address_table;
585 /* Entry for the above hash table. */
586 struct GTY(()) temp_slot_address_entry {
589 struct temp_slot *temp_slot;
592 /* Removes temporary slot TEMP from LIST. */
595 cut_slot_from_list (struct temp_slot *temp, struct temp_slot **list)
598 temp->next->prev = temp->prev;
600 temp->prev->next = temp->next;
604 temp->prev = temp->next = NULL;
607 /* Inserts temporary slot TEMP to LIST. */
610 insert_slot_to_list (struct temp_slot *temp, struct temp_slot **list)
614 (*list)->prev = temp;
619 /* Returns the list of used temp slots at LEVEL. */
621 static struct temp_slot **
622 temp_slots_at_level (int level)
624 if (level >= (int) VEC_length (temp_slot_p, used_temp_slots))
625 VEC_safe_grow_cleared (temp_slot_p, gc, used_temp_slots, level + 1);
627 return &(VEC_address (temp_slot_p, used_temp_slots)[level]);
630 /* Returns the maximal temporary slot level. */
633 max_slot_level (void)
635 if (!used_temp_slots)
638 return VEC_length (temp_slot_p, used_temp_slots) - 1;
641 /* Moves temporary slot TEMP to LEVEL. */
644 move_slot_to_level (struct temp_slot *temp, int level)
646 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
647 insert_slot_to_list (temp, temp_slots_at_level (level));
651 /* Make temporary slot TEMP available. */
654 make_slot_available (struct temp_slot *temp)
656 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
657 insert_slot_to_list (temp, &avail_temp_slots);
662 /* Compute the hash value for an address -> temp slot mapping.
663 The value is cached on the mapping entry. */
665 temp_slot_address_compute_hash (struct temp_slot_address_entry *t)
667 int do_not_record = 0;
668 return hash_rtx (t->address, GET_MODE (t->address),
669 &do_not_record, NULL, false);
672 /* Return the hash value for an address -> temp slot mapping. */
674 temp_slot_address_hash (const void *p)
676 const struct temp_slot_address_entry *t;
677 t = (const struct temp_slot_address_entry *) p;
681 /* Compare two address -> temp slot mapping entries. */
683 temp_slot_address_eq (const void *p1, const void *p2)
685 const struct temp_slot_address_entry *t1, *t2;
686 t1 = (const struct temp_slot_address_entry *) p1;
687 t2 = (const struct temp_slot_address_entry *) p2;
688 return exp_equiv_p (t1->address, t2->address, 0, true);
691 /* Add ADDRESS as an alias of TEMP_SLOT to the addess -> temp slot mapping. */
693 insert_temp_slot_address (rtx address, struct temp_slot *temp_slot)
696 struct temp_slot_address_entry *t = ggc_alloc_temp_slot_address_entry ();
697 t->address = address;
698 t->temp_slot = temp_slot;
699 t->hash = temp_slot_address_compute_hash (t);
700 slot = htab_find_slot_with_hash (temp_slot_address_table, t, t->hash, INSERT);
704 /* Remove an address -> temp slot mapping entry if the temp slot is
705 not in use anymore. Callback for remove_unused_temp_slot_addresses. */
707 remove_unused_temp_slot_addresses_1 (void **slot, void *data ATTRIBUTE_UNUSED)
709 const struct temp_slot_address_entry *t;
710 t = (const struct temp_slot_address_entry *) *slot;
711 if (! t->temp_slot->in_use)
716 /* Remove all mappings of addresses to unused temp slots. */
718 remove_unused_temp_slot_addresses (void)
720 htab_traverse (temp_slot_address_table,
721 remove_unused_temp_slot_addresses_1,
725 /* Find the temp slot corresponding to the object at address X. */
727 static struct temp_slot *
728 find_temp_slot_from_address (rtx x)
731 struct temp_slot_address_entry tmp, *t;
733 /* First try the easy way:
734 See if X exists in the address -> temp slot mapping. */
736 tmp.temp_slot = NULL;
737 tmp.hash = temp_slot_address_compute_hash (&tmp);
738 t = (struct temp_slot_address_entry *)
739 htab_find_with_hash (temp_slot_address_table, &tmp, tmp.hash);
743 /* If we have a sum involving a register, see if it points to a temp
745 if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 0))
746 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
748 else if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 1))
749 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
752 /* Last resort: Address is a virtual stack var address. */
753 if (GET_CODE (x) == PLUS
754 && XEXP (x, 0) == virtual_stack_vars_rtx
755 && CONST_INT_P (XEXP (x, 1)))
758 for (i = max_slot_level (); i >= 0; i--)
759 for (p = *temp_slots_at_level (i); p; p = p->next)
761 if (INTVAL (XEXP (x, 1)) >= p->base_offset
762 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size)
770 /* Allocate a temporary stack slot and record it for possible later
773 MODE is the machine mode to be given to the returned rtx.
775 SIZE is the size in units of the space required. We do no rounding here
776 since assign_stack_local will do any required rounding.
778 KEEP is 1 if this slot is to be retained after a call to
779 free_temp_slots. Automatic variables for a block are allocated
780 with this flag. KEEP values of 2 or 3 were needed respectively
781 for variables whose lifetime is controlled by CLEANUP_POINT_EXPRs
782 or for SAVE_EXPRs, but they are now unused.
784 TYPE is the type that will be used for the stack slot. */
787 assign_stack_temp_for_type (enum machine_mode mode, HOST_WIDE_INT size,
791 struct temp_slot *p, *best_p = 0, *selected = NULL, **pp;
794 /* If SIZE is -1 it means that somebody tried to allocate a temporary
795 of a variable size. */
796 gcc_assert (size != -1);
798 /* These are now unused. */
799 gcc_assert (keep <= 1);
801 align = get_stack_local_alignment (type, mode);
803 /* Try to find an available, already-allocated temporary of the proper
804 mode which meets the size and alignment requirements. Choose the
805 smallest one with the closest alignment.
807 If assign_stack_temp is called outside of the tree->rtl expansion,
808 we cannot reuse the stack slots (that may still refer to
809 VIRTUAL_STACK_VARS_REGNUM). */
810 if (!virtuals_instantiated)
812 for (p = avail_temp_slots; p; p = p->next)
814 if (p->align >= align && p->size >= size
815 && GET_MODE (p->slot) == mode
816 && objects_must_conflict_p (p->type, type)
817 && (best_p == 0 || best_p->size > p->size
818 || (best_p->size == p->size && best_p->align > p->align)))
820 if (p->align == align && p->size == size)
823 cut_slot_from_list (selected, &avail_temp_slots);
832 /* Make our best, if any, the one to use. */
836 cut_slot_from_list (selected, &avail_temp_slots);
838 /* If there are enough aligned bytes left over, make them into a new
839 temp_slot so that the extra bytes don't get wasted. Do this only
840 for BLKmode slots, so that we can be sure of the alignment. */
841 if (GET_MODE (best_p->slot) == BLKmode)
843 int alignment = best_p->align / BITS_PER_UNIT;
844 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
846 if (best_p->size - rounded_size >= alignment)
848 p = ggc_alloc_temp_slot ();
849 p->in_use = p->addr_taken = 0;
850 p->size = best_p->size - rounded_size;
851 p->base_offset = best_p->base_offset + rounded_size;
852 p->full_size = best_p->full_size - rounded_size;
853 p->slot = adjust_address_nv (best_p->slot, BLKmode, rounded_size);
854 p->align = best_p->align;
855 p->type = best_p->type;
856 insert_slot_to_list (p, &avail_temp_slots);
858 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
861 best_p->size = rounded_size;
862 best_p->full_size = rounded_size;
867 /* If we still didn't find one, make a new temporary. */
870 HOST_WIDE_INT frame_offset_old = frame_offset;
872 p = ggc_alloc_temp_slot ();
874 /* We are passing an explicit alignment request to assign_stack_local.
875 One side effect of that is assign_stack_local will not round SIZE
876 to ensure the frame offset remains suitably aligned.
878 So for requests which depended on the rounding of SIZE, we go ahead
879 and round it now. We also make sure ALIGNMENT is at least
880 BIGGEST_ALIGNMENT. */
881 gcc_assert (mode != BLKmode || align == BIGGEST_ALIGNMENT);
882 p->slot = assign_stack_local_1 (mode,
892 /* The following slot size computation is necessary because we don't
893 know the actual size of the temporary slot until assign_stack_local
894 has performed all the frame alignment and size rounding for the
895 requested temporary. Note that extra space added for alignment
896 can be either above or below this stack slot depending on which
897 way the frame grows. We include the extra space if and only if it
898 is above this slot. */
899 if (FRAME_GROWS_DOWNWARD)
900 p->size = frame_offset_old - frame_offset;
904 /* Now define the fields used by combine_temp_slots. */
905 if (FRAME_GROWS_DOWNWARD)
907 p->base_offset = frame_offset;
908 p->full_size = frame_offset_old - frame_offset;
912 p->base_offset = frame_offset_old;
913 p->full_size = frame_offset - frame_offset_old;
923 p->level = temp_slot_level;
926 pp = temp_slots_at_level (p->level);
927 insert_slot_to_list (p, pp);
928 insert_temp_slot_address (XEXP (p->slot, 0), p);
930 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
931 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
932 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list);
934 /* If we know the alias set for the memory that will be used, use
935 it. If there's no TYPE, then we don't know anything about the
936 alias set for the memory. */
937 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
938 set_mem_align (slot, align);
940 /* If a type is specified, set the relevant flags. */
943 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
944 gcc_checking_assert (!MEM_SCALAR_P (slot) && !MEM_IN_STRUCT_P (slot));
945 if (AGGREGATE_TYPE_P (type) || TREE_CODE (type) == COMPLEX_TYPE)
946 MEM_IN_STRUCT_P (slot) = 1;
948 MEM_SCALAR_P (slot) = 1;
950 MEM_NOTRAP_P (slot) = 1;
955 /* Allocate a temporary stack slot and record it for possible later
956 reuse. First three arguments are same as in preceding function. */
959 assign_stack_temp (enum machine_mode mode, HOST_WIDE_INT size, int keep)
961 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
964 /* Assign a temporary.
965 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
966 and so that should be used in error messages. In either case, we
967 allocate of the given type.
968 KEEP is as for assign_stack_temp.
969 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
970 it is 0 if a register is OK.
971 DONT_PROMOTE is 1 if we should not promote values in register
975 assign_temp (tree type_or_decl, int keep, int memory_required,
976 int dont_promote ATTRIBUTE_UNUSED)
979 enum machine_mode mode;
984 if (DECL_P (type_or_decl))
985 decl = type_or_decl, type = TREE_TYPE (decl);
987 decl = NULL, type = type_or_decl;
989 mode = TYPE_MODE (type);
991 unsignedp = TYPE_UNSIGNED (type);
994 if (mode == BLKmode || memory_required)
996 HOST_WIDE_INT size = int_size_in_bytes (type);
999 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
1000 problems with allocating the stack space. */
1004 /* Unfortunately, we don't yet know how to allocate variable-sized
1005 temporaries. However, sometimes we can find a fixed upper limit on
1006 the size, so try that instead. */
1007 else if (size == -1)
1008 size = max_int_size_in_bytes (type);
1010 /* The size of the temporary may be too large to fit into an integer. */
1011 /* ??? Not sure this should happen except for user silliness, so limit
1012 this to things that aren't compiler-generated temporaries. The
1013 rest of the time we'll die in assign_stack_temp_for_type. */
1014 if (decl && size == -1
1015 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
1017 error ("size of variable %q+D is too large", decl);
1021 tmp = assign_stack_temp_for_type (mode, size, keep, type);
1027 mode = promote_mode (type, mode, &unsignedp);
1030 return gen_reg_rtx (mode);
1033 /* Combine temporary stack slots which are adjacent on the stack.
1035 This allows for better use of already allocated stack space. This is only
1036 done for BLKmode slots because we can be sure that we won't have alignment
1037 problems in this case. */
1040 combine_temp_slots (void)
1042 struct temp_slot *p, *q, *next, *next_q;
1045 /* We can't combine slots, because the information about which slot
1046 is in which alias set will be lost. */
1047 if (flag_strict_aliasing)
1050 /* If there are a lot of temp slots, don't do anything unless
1051 high levels of optimization. */
1052 if (! flag_expensive_optimizations)
1053 for (p = avail_temp_slots, num_slots = 0; p; p = p->next, num_slots++)
1054 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
1057 for (p = avail_temp_slots; p; p = next)
1063 if (GET_MODE (p->slot) != BLKmode)
1066 for (q = p->next; q; q = next_q)
1072 if (GET_MODE (q->slot) != BLKmode)
1075 if (p->base_offset + p->full_size == q->base_offset)
1077 /* Q comes after P; combine Q into P. */
1079 p->full_size += q->full_size;
1082 else if (q->base_offset + q->full_size == p->base_offset)
1084 /* P comes after Q; combine P into Q. */
1086 q->full_size += p->full_size;
1091 cut_slot_from_list (q, &avail_temp_slots);
1094 /* Either delete P or advance past it. */
1096 cut_slot_from_list (p, &avail_temp_slots);
1100 /* Indicate that NEW_RTX is an alternate way of referring to the temp
1101 slot that previously was known by OLD_RTX. */
1104 update_temp_slot_address (rtx old_rtx, rtx new_rtx)
1106 struct temp_slot *p;
1108 if (rtx_equal_p (old_rtx, new_rtx))
1111 p = find_temp_slot_from_address (old_rtx);
1113 /* If we didn't find one, see if both OLD_RTX is a PLUS. If so, and
1114 NEW_RTX is a register, see if one operand of the PLUS is a
1115 temporary location. If so, NEW_RTX points into it. Otherwise,
1116 if both OLD_RTX and NEW_RTX are a PLUS and if there is a register
1117 in common between them. If so, try a recursive call on those
1121 if (GET_CODE (old_rtx) != PLUS)
1124 if (REG_P (new_rtx))
1126 update_temp_slot_address (XEXP (old_rtx, 0), new_rtx);
1127 update_temp_slot_address (XEXP (old_rtx, 1), new_rtx);
1130 else if (GET_CODE (new_rtx) != PLUS)
1133 if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 0)))
1134 update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 1));
1135 else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 0)))
1136 update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 1));
1137 else if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 1)))
1138 update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 0));
1139 else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 1)))
1140 update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 0));
1145 /* Otherwise add an alias for the temp's address. */
1146 insert_temp_slot_address (new_rtx, p);
1149 /* If X could be a reference to a temporary slot, mark the fact that its
1150 address was taken. */
1153 mark_temp_addr_taken (rtx x)
1155 struct temp_slot *p;
1160 /* If X is not in memory or is at a constant address, it cannot be in
1161 a temporary slot. */
1162 if (!MEM_P (x) || CONSTANT_P (XEXP (x, 0)))
1165 p = find_temp_slot_from_address (XEXP (x, 0));
1170 /* If X could be a reference to a temporary slot, mark that slot as
1171 belonging to the to one level higher than the current level. If X
1172 matched one of our slots, just mark that one. Otherwise, we can't
1173 easily predict which it is, so upgrade all of them. Kept slots
1174 need not be touched.
1176 This is called when an ({...}) construct occurs and a statement
1177 returns a value in memory. */
1180 preserve_temp_slots (rtx x)
1182 struct temp_slot *p = 0, *next;
1184 /* If there is no result, we still might have some objects whose address
1185 were taken, so we need to make sure they stay around. */
1188 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1193 move_slot_to_level (p, temp_slot_level - 1);
1199 /* If X is a register that is being used as a pointer, see if we have
1200 a temporary slot we know it points to. To be consistent with
1201 the code below, we really should preserve all non-kept slots
1202 if we can't find a match, but that seems to be much too costly. */
1203 if (REG_P (x) && REG_POINTER (x))
1204 p = find_temp_slot_from_address (x);
1206 /* If X is not in memory or is at a constant address, it cannot be in
1207 a temporary slot, but it can contain something whose address was
1209 if (p == 0 && (!MEM_P (x) || CONSTANT_P (XEXP (x, 0))))
1211 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1216 move_slot_to_level (p, temp_slot_level - 1);
1222 /* First see if we can find a match. */
1224 p = find_temp_slot_from_address (XEXP (x, 0));
1228 /* Move everything at our level whose address was taken to our new
1229 level in case we used its address. */
1230 struct temp_slot *q;
1232 if (p->level == temp_slot_level)
1234 for (q = *temp_slots_at_level (temp_slot_level); q; q = next)
1238 if (p != q && q->addr_taken)
1239 move_slot_to_level (q, temp_slot_level - 1);
1242 move_slot_to_level (p, temp_slot_level - 1);
1248 /* Otherwise, preserve all non-kept slots at this level. */
1249 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1254 move_slot_to_level (p, temp_slot_level - 1);
1258 /* Free all temporaries used so far. This is normally called at the
1259 end of generating code for a statement. */
1262 free_temp_slots (void)
1264 struct temp_slot *p, *next;
1265 bool some_available = false;
1267 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1273 make_slot_available (p);
1274 some_available = true;
1280 remove_unused_temp_slot_addresses ();
1281 combine_temp_slots ();
1285 /* Push deeper into the nesting level for stack temporaries. */
1288 push_temp_slots (void)
1293 /* Pop a temporary nesting level. All slots in use in the current level
1297 pop_temp_slots (void)
1299 struct temp_slot *p, *next;
1300 bool some_available = false;
1302 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1305 make_slot_available (p);
1306 some_available = true;
1311 remove_unused_temp_slot_addresses ();
1312 combine_temp_slots ();
1318 /* Initialize temporary slots. */
1321 init_temp_slots (void)
1323 /* We have not allocated any temporaries yet. */
1324 avail_temp_slots = 0;
1325 used_temp_slots = 0;
1326 temp_slot_level = 0;
1328 /* Set up the table to map addresses to temp slots. */
1329 if (! temp_slot_address_table)
1330 temp_slot_address_table = htab_create_ggc (32,
1331 temp_slot_address_hash,
1332 temp_slot_address_eq,
1335 htab_empty (temp_slot_address_table);
1338 /* These routines are responsible for converting virtual register references
1339 to the actual hard register references once RTL generation is complete.
1341 The following four variables are used for communication between the
1342 routines. They contain the offsets of the virtual registers from their
1343 respective hard registers. */
1345 static int in_arg_offset;
1346 static int var_offset;
1347 static int dynamic_offset;
1348 static int out_arg_offset;
1349 static int cfa_offset;
1351 /* In most machines, the stack pointer register is equivalent to the bottom
1354 #ifndef STACK_POINTER_OFFSET
1355 #define STACK_POINTER_OFFSET 0
1358 /* If not defined, pick an appropriate default for the offset of dynamically
1359 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1360 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1362 #ifndef STACK_DYNAMIC_OFFSET
1364 /* The bottom of the stack points to the actual arguments. If
1365 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1366 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1367 stack space for register parameters is not pushed by the caller, but
1368 rather part of the fixed stack areas and hence not included in
1369 `crtl->outgoing_args_size'. Nevertheless, we must allow
1370 for it when allocating stack dynamic objects. */
1372 #if defined(REG_PARM_STACK_SPACE)
1373 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1374 ((ACCUMULATE_OUTGOING_ARGS \
1375 ? (crtl->outgoing_args_size \
1376 + (OUTGOING_REG_PARM_STACK_SPACE ((!(FNDECL) ? NULL_TREE : TREE_TYPE (FNDECL))) ? 0 \
1377 : REG_PARM_STACK_SPACE (FNDECL))) \
1378 : 0) + (STACK_POINTER_OFFSET))
1380 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1381 ((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : 0) \
1382 + (STACK_POINTER_OFFSET))
1387 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1388 is a virtual register, return the equivalent hard register and set the
1389 offset indirectly through the pointer. Otherwise, return 0. */
1392 instantiate_new_reg (rtx x, HOST_WIDE_INT *poffset)
1395 HOST_WIDE_INT offset;
1397 if (x == virtual_incoming_args_rtx)
1399 if (stack_realign_drap)
1401 /* Replace virtual_incoming_args_rtx with internal arg
1402 pointer if DRAP is used to realign stack. */
1403 new_rtx = crtl->args.internal_arg_pointer;
1407 new_rtx = arg_pointer_rtx, offset = in_arg_offset;
1409 else if (x == virtual_stack_vars_rtx)
1410 new_rtx = frame_pointer_rtx, offset = var_offset;
1411 else if (x == virtual_stack_dynamic_rtx)
1412 new_rtx = stack_pointer_rtx, offset = dynamic_offset;
1413 else if (x == virtual_outgoing_args_rtx)
1414 new_rtx = stack_pointer_rtx, offset = out_arg_offset;
1415 else if (x == virtual_cfa_rtx)
1417 #ifdef FRAME_POINTER_CFA_OFFSET
1418 new_rtx = frame_pointer_rtx;
1420 new_rtx = arg_pointer_rtx;
1422 offset = cfa_offset;
1424 else if (x == virtual_preferred_stack_boundary_rtx)
1426 new_rtx = GEN_INT (crtl->preferred_stack_boundary / BITS_PER_UNIT);
1436 /* A subroutine of instantiate_virtual_regs, called via for_each_rtx.
1437 Instantiate any virtual registers present inside of *LOC. The expression
1438 is simplified, as much as possible, but is not to be considered "valid"
1439 in any sense implied by the target. If any change is made, set CHANGED
1443 instantiate_virtual_regs_in_rtx (rtx *loc, void *data)
1445 HOST_WIDE_INT offset;
1446 bool *changed = (bool *) data;
1453 switch (GET_CODE (x))
1456 new_rtx = instantiate_new_reg (x, &offset);
1459 *loc = plus_constant (new_rtx, offset);
1466 new_rtx = instantiate_new_reg (XEXP (x, 0), &offset);
1469 new_rtx = plus_constant (new_rtx, offset);
1470 *loc = simplify_gen_binary (PLUS, GET_MODE (x), new_rtx, XEXP (x, 1));
1476 /* FIXME -- from old code */
1477 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1478 we can commute the PLUS and SUBREG because pointers into the
1479 frame are well-behaved. */
1489 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1490 matches the predicate for insn CODE operand OPERAND. */
1493 safe_insn_predicate (int code, int operand, rtx x)
1495 return code < 0 || insn_operand_matches ((enum insn_code) code, operand, x);
1498 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1499 registers present inside of insn. The result will be a valid insn. */
1502 instantiate_virtual_regs_in_insn (rtx insn)
1504 HOST_WIDE_INT offset;
1506 bool any_change = false;
1507 rtx set, new_rtx, x, seq;
1509 /* There are some special cases to be handled first. */
1510 set = single_set (insn);
1513 /* We're allowed to assign to a virtual register. This is interpreted
1514 to mean that the underlying register gets assigned the inverse
1515 transformation. This is used, for example, in the handling of
1517 new_rtx = instantiate_new_reg (SET_DEST (set), &offset);
1522 for_each_rtx (&SET_SRC (set), instantiate_virtual_regs_in_rtx, NULL);
1523 x = simplify_gen_binary (PLUS, GET_MODE (new_rtx), SET_SRC (set),
1525 x = force_operand (x, new_rtx);
1527 emit_move_insn (new_rtx, x);
1532 emit_insn_before (seq, insn);
1537 /* Handle a straight copy from a virtual register by generating a
1538 new add insn. The difference between this and falling through
1539 to the generic case is avoiding a new pseudo and eliminating a
1540 move insn in the initial rtl stream. */
1541 new_rtx = instantiate_new_reg (SET_SRC (set), &offset);
1542 if (new_rtx && offset != 0
1543 && REG_P (SET_DEST (set))
1544 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1548 x = expand_simple_binop (GET_MODE (SET_DEST (set)), PLUS,
1549 new_rtx, GEN_INT (offset), SET_DEST (set),
1550 1, OPTAB_LIB_WIDEN);
1551 if (x != SET_DEST (set))
1552 emit_move_insn (SET_DEST (set), x);
1557 emit_insn_before (seq, insn);
1562 extract_insn (insn);
1563 insn_code = INSN_CODE (insn);
1565 /* Handle a plus involving a virtual register by determining if the
1566 operands remain valid if they're modified in place. */
1567 if (GET_CODE (SET_SRC (set)) == PLUS
1568 && recog_data.n_operands >= 3
1569 && recog_data.operand_loc[1] == &XEXP (SET_SRC (set), 0)
1570 && recog_data.operand_loc[2] == &XEXP (SET_SRC (set), 1)
1571 && CONST_INT_P (recog_data.operand[2])
1572 && (new_rtx = instantiate_new_reg (recog_data.operand[1], &offset)))
1574 offset += INTVAL (recog_data.operand[2]);
1576 /* If the sum is zero, then replace with a plain move. */
1578 && REG_P (SET_DEST (set))
1579 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1582 emit_move_insn (SET_DEST (set), new_rtx);
1586 emit_insn_before (seq, insn);
1591 x = gen_int_mode (offset, recog_data.operand_mode[2]);
1593 /* Using validate_change and apply_change_group here leaves
1594 recog_data in an invalid state. Since we know exactly what
1595 we want to check, do those two by hand. */
1596 if (safe_insn_predicate (insn_code, 1, new_rtx)
1597 && safe_insn_predicate (insn_code, 2, x))
1599 *recog_data.operand_loc[1] = recog_data.operand[1] = new_rtx;
1600 *recog_data.operand_loc[2] = recog_data.operand[2] = x;
1603 /* Fall through into the regular operand fixup loop in
1604 order to take care of operands other than 1 and 2. */
1610 extract_insn (insn);
1611 insn_code = INSN_CODE (insn);
1614 /* In the general case, we expect virtual registers to appear only in
1615 operands, and then only as either bare registers or inside memories. */
1616 for (i = 0; i < recog_data.n_operands; ++i)
1618 x = recog_data.operand[i];
1619 switch (GET_CODE (x))
1623 rtx addr = XEXP (x, 0);
1624 bool changed = false;
1626 for_each_rtx (&addr, instantiate_virtual_regs_in_rtx, &changed);
1631 x = replace_equiv_address (x, addr);
1632 /* It may happen that the address with the virtual reg
1633 was valid (e.g. based on the virtual stack reg, which might
1634 be acceptable to the predicates with all offsets), whereas
1635 the address now isn't anymore, for instance when the address
1636 is still offsetted, but the base reg isn't virtual-stack-reg
1637 anymore. Below we would do a force_reg on the whole operand,
1638 but this insn might actually only accept memory. Hence,
1639 before doing that last resort, try to reload the address into
1640 a register, so this operand stays a MEM. */
1641 if (!safe_insn_predicate (insn_code, i, x))
1643 addr = force_reg (GET_MODE (addr), addr);
1644 x = replace_equiv_address (x, addr);
1649 emit_insn_before (seq, insn);
1654 new_rtx = instantiate_new_reg (x, &offset);
1655 if (new_rtx == NULL)
1663 /* Careful, special mode predicates may have stuff in
1664 insn_data[insn_code].operand[i].mode that isn't useful
1665 to us for computing a new value. */
1666 /* ??? Recognize address_operand and/or "p" constraints
1667 to see if (plus new offset) is a valid before we put
1668 this through expand_simple_binop. */
1669 x = expand_simple_binop (GET_MODE (x), PLUS, new_rtx,
1670 GEN_INT (offset), NULL_RTX,
1671 1, OPTAB_LIB_WIDEN);
1674 emit_insn_before (seq, insn);
1679 new_rtx = instantiate_new_reg (SUBREG_REG (x), &offset);
1680 if (new_rtx == NULL)
1685 new_rtx = expand_simple_binop (GET_MODE (new_rtx), PLUS, new_rtx,
1686 GEN_INT (offset), NULL_RTX,
1687 1, OPTAB_LIB_WIDEN);
1690 emit_insn_before (seq, insn);
1692 x = simplify_gen_subreg (recog_data.operand_mode[i], new_rtx,
1693 GET_MODE (new_rtx), SUBREG_BYTE (x));
1701 /* At this point, X contains the new value for the operand.
1702 Validate the new value vs the insn predicate. Note that
1703 asm insns will have insn_code -1 here. */
1704 if (!safe_insn_predicate (insn_code, i, x))
1709 gcc_assert (REGNO (x) <= LAST_VIRTUAL_REGISTER);
1710 x = copy_to_reg (x);
1713 x = force_reg (insn_data[insn_code].operand[i].mode, x);
1717 emit_insn_before (seq, insn);
1720 *recog_data.operand_loc[i] = recog_data.operand[i] = x;
1726 /* Propagate operand changes into the duplicates. */
1727 for (i = 0; i < recog_data.n_dups; ++i)
1728 *recog_data.dup_loc[i]
1729 = copy_rtx (recog_data.operand[(unsigned)recog_data.dup_num[i]]);
1731 /* Force re-recognition of the instruction for validation. */
1732 INSN_CODE (insn) = -1;
1735 if (asm_noperands (PATTERN (insn)) >= 0)
1737 if (!check_asm_operands (PATTERN (insn)))
1739 error_for_asm (insn, "impossible constraint in %<asm%>");
1745 if (recog_memoized (insn) < 0)
1746 fatal_insn_not_found (insn);
1750 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1751 do any instantiation required. */
1754 instantiate_decl_rtl (rtx x)
1761 /* If this is a CONCAT, recurse for the pieces. */
1762 if (GET_CODE (x) == CONCAT)
1764 instantiate_decl_rtl (XEXP (x, 0));
1765 instantiate_decl_rtl (XEXP (x, 1));
1769 /* If this is not a MEM, no need to do anything. Similarly if the
1770 address is a constant or a register that is not a virtual register. */
1775 if (CONSTANT_P (addr)
1777 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
1778 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
1781 for_each_rtx (&XEXP (x, 0), instantiate_virtual_regs_in_rtx, NULL);
1784 /* Helper for instantiate_decls called via walk_tree: Process all decls
1785 in the given DECL_VALUE_EXPR. */
1788 instantiate_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
1796 if (DECL_RTL_SET_P (t))
1797 instantiate_decl_rtl (DECL_RTL (t));
1798 if (TREE_CODE (t) == PARM_DECL && DECL_NAMELESS (t)
1799 && DECL_INCOMING_RTL (t))
1800 instantiate_decl_rtl (DECL_INCOMING_RTL (t));
1801 if ((TREE_CODE (t) == VAR_DECL
1802 || TREE_CODE (t) == RESULT_DECL)
1803 && DECL_HAS_VALUE_EXPR_P (t))
1805 tree v = DECL_VALUE_EXPR (t);
1806 walk_tree (&v, instantiate_expr, NULL, NULL);
1813 /* Subroutine of instantiate_decls: Process all decls in the given
1814 BLOCK node and all its subblocks. */
1817 instantiate_decls_1 (tree let)
1821 for (t = BLOCK_VARS (let); t; t = DECL_CHAIN (t))
1823 if (DECL_RTL_SET_P (t))
1824 instantiate_decl_rtl (DECL_RTL (t));
1825 if (TREE_CODE (t) == VAR_DECL && DECL_HAS_VALUE_EXPR_P (t))
1827 tree v = DECL_VALUE_EXPR (t);
1828 walk_tree (&v, instantiate_expr, NULL, NULL);
1832 /* Process all subblocks. */
1833 for (t = BLOCK_SUBBLOCKS (let); t; t = BLOCK_CHAIN (t))
1834 instantiate_decls_1 (t);
1837 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1838 all virtual registers in their DECL_RTL's. */
1841 instantiate_decls (tree fndecl)
1846 /* Process all parameters of the function. */
1847 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = DECL_CHAIN (decl))
1849 instantiate_decl_rtl (DECL_RTL (decl));
1850 instantiate_decl_rtl (DECL_INCOMING_RTL (decl));
1851 if (DECL_HAS_VALUE_EXPR_P (decl))
1853 tree v = DECL_VALUE_EXPR (decl);
1854 walk_tree (&v, instantiate_expr, NULL, NULL);
1858 if ((decl = DECL_RESULT (fndecl))
1859 && TREE_CODE (decl) == RESULT_DECL)
1861 if (DECL_RTL_SET_P (decl))
1862 instantiate_decl_rtl (DECL_RTL (decl));
1863 if (DECL_HAS_VALUE_EXPR_P (decl))
1865 tree v = DECL_VALUE_EXPR (decl);
1866 walk_tree (&v, instantiate_expr, NULL, NULL);
1870 /* Now process all variables defined in the function or its subblocks. */
1871 instantiate_decls_1 (DECL_INITIAL (fndecl));
1873 FOR_EACH_LOCAL_DECL (cfun, ix, decl)
1874 if (DECL_RTL_SET_P (decl))
1875 instantiate_decl_rtl (DECL_RTL (decl));
1876 VEC_free (tree, gc, cfun->local_decls);
1879 /* Pass through the INSNS of function FNDECL and convert virtual register
1880 references to hard register references. */
1883 instantiate_virtual_regs (void)
1887 /* Compute the offsets to use for this function. */
1888 in_arg_offset = FIRST_PARM_OFFSET (current_function_decl);
1889 var_offset = STARTING_FRAME_OFFSET;
1890 dynamic_offset = STACK_DYNAMIC_OFFSET (current_function_decl);
1891 out_arg_offset = STACK_POINTER_OFFSET;
1892 #ifdef FRAME_POINTER_CFA_OFFSET
1893 cfa_offset = FRAME_POINTER_CFA_OFFSET (current_function_decl);
1895 cfa_offset = ARG_POINTER_CFA_OFFSET (current_function_decl);
1898 /* Initialize recognition, indicating that volatile is OK. */
1901 /* Scan through all the insns, instantiating every virtual register still
1903 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
1906 /* These patterns in the instruction stream can never be recognized.
1907 Fortunately, they shouldn't contain virtual registers either. */
1908 if (GET_CODE (PATTERN (insn)) == USE
1909 || GET_CODE (PATTERN (insn)) == CLOBBER
1910 || GET_CODE (PATTERN (insn)) == ADDR_VEC
1911 || GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC
1912 || GET_CODE (PATTERN (insn)) == ASM_INPUT)
1914 else if (DEBUG_INSN_P (insn))
1915 for_each_rtx (&INSN_VAR_LOCATION (insn),
1916 instantiate_virtual_regs_in_rtx, NULL);
1918 instantiate_virtual_regs_in_insn (insn);
1920 if (INSN_DELETED_P (insn))
1923 for_each_rtx (®_NOTES (insn), instantiate_virtual_regs_in_rtx, NULL);
1925 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1927 for_each_rtx (&CALL_INSN_FUNCTION_USAGE (insn),
1928 instantiate_virtual_regs_in_rtx, NULL);
1931 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1932 instantiate_decls (current_function_decl);
1934 targetm.instantiate_decls ();
1936 /* Indicate that, from now on, assign_stack_local should use
1937 frame_pointer_rtx. */
1938 virtuals_instantiated = 1;
1943 struct rtl_opt_pass pass_instantiate_virtual_regs =
1949 instantiate_virtual_regs, /* execute */
1952 0, /* static_pass_number */
1953 TV_NONE, /* tv_id */
1954 0, /* properties_required */
1955 0, /* properties_provided */
1956 0, /* properties_destroyed */
1957 0, /* todo_flags_start */
1958 0 /* todo_flags_finish */
1963 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
1964 This means a type for which function calls must pass an address to the
1965 function or get an address back from the function.
1966 EXP may be a type node or an expression (whose type is tested). */
1969 aggregate_value_p (const_tree exp, const_tree fntype)
1971 const_tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
1972 int i, regno, nregs;
1976 switch (TREE_CODE (fntype))
1980 tree fndecl = get_callee_fndecl (fntype);
1982 ? TREE_TYPE (fndecl)
1983 : TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (fntype))));
1987 fntype = TREE_TYPE (fntype);
1992 case IDENTIFIER_NODE:
1996 /* We don't expect other tree types here. */
2000 if (VOID_TYPE_P (type))
2003 /* If a record should be passed the same as its first (and only) member
2004 don't pass it as an aggregate. */
2005 if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
2006 return aggregate_value_p (first_field (type), fntype);
2008 /* If the front end has decided that this needs to be passed by
2009 reference, do so. */
2010 if ((TREE_CODE (exp) == PARM_DECL || TREE_CODE (exp) == RESULT_DECL)
2011 && DECL_BY_REFERENCE (exp))
2014 /* Function types that are TREE_ADDRESSABLE force return in memory. */
2015 if (fntype && TREE_ADDRESSABLE (fntype))
2018 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
2019 and thus can't be returned in registers. */
2020 if (TREE_ADDRESSABLE (type))
2023 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
2026 if (targetm.calls.return_in_memory (type, fntype))
2029 /* Make sure we have suitable call-clobbered regs to return
2030 the value in; if not, we must return it in memory. */
2031 reg = hard_function_value (type, 0, fntype, 0);
2033 /* If we have something other than a REG (e.g. a PARALLEL), then assume
2038 regno = REGNO (reg);
2039 nregs = hard_regno_nregs[regno][TYPE_MODE (type)];
2040 for (i = 0; i < nregs; i++)
2041 if (! call_used_regs[regno + i])
2047 /* Return true if we should assign DECL a pseudo register; false if it
2048 should live on the local stack. */
2051 use_register_for_decl (const_tree decl)
2053 if (!targetm.calls.allocate_stack_slots_for_args())
2056 /* Honor volatile. */
2057 if (TREE_SIDE_EFFECTS (decl))
2060 /* Honor addressability. */
2061 if (TREE_ADDRESSABLE (decl))
2064 /* Only register-like things go in registers. */
2065 if (DECL_MODE (decl) == BLKmode)
2068 /* If -ffloat-store specified, don't put explicit float variables
2070 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
2071 propagates values across these stores, and it probably shouldn't. */
2072 if (flag_float_store && FLOAT_TYPE_P (TREE_TYPE (decl)))
2075 /* If we're not interested in tracking debugging information for
2076 this decl, then we can certainly put it in a register. */
2077 if (DECL_IGNORED_P (decl))
2083 if (!DECL_REGISTER (decl))
2086 switch (TREE_CODE (TREE_TYPE (decl)))
2090 case QUAL_UNION_TYPE:
2091 /* When not optimizing, disregard register keyword for variables with
2092 types containing methods, otherwise the methods won't be callable
2093 from the debugger. */
2094 if (TYPE_METHODS (TREE_TYPE (decl)))
2104 /* Return true if TYPE should be passed by invisible reference. */
2107 pass_by_reference (CUMULATIVE_ARGS *ca, enum machine_mode mode,
2108 tree type, bool named_arg)
2112 /* If this type contains non-trivial constructors, then it is
2113 forbidden for the middle-end to create any new copies. */
2114 if (TREE_ADDRESSABLE (type))
2117 /* GCC post 3.4 passes *all* variable sized types by reference. */
2118 if (!TYPE_SIZE (type) || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
2121 /* If a record type should be passed the same as its first (and only)
2122 member, use the type and mode of that member. */
2123 if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
2125 type = TREE_TYPE (first_field (type));
2126 mode = TYPE_MODE (type);
2130 return targetm.calls.pass_by_reference (pack_cumulative_args (ca), mode,
2134 /* Return true if TYPE, which is passed by reference, should be callee
2135 copied instead of caller copied. */
2138 reference_callee_copied (CUMULATIVE_ARGS *ca, enum machine_mode mode,
2139 tree type, bool named_arg)
2141 if (type && TREE_ADDRESSABLE (type))
2143 return targetm.calls.callee_copies (pack_cumulative_args (ca), mode, type,
2147 /* Structures to communicate between the subroutines of assign_parms.
2148 The first holds data persistent across all parameters, the second
2149 is cleared out for each parameter. */
2151 struct assign_parm_data_all
2153 /* When INIT_CUMULATIVE_ARGS gets revamped, allocating CUMULATIVE_ARGS
2154 should become a job of the target or otherwise encapsulated. */
2155 CUMULATIVE_ARGS args_so_far_v;
2156 cumulative_args_t args_so_far;
2157 struct args_size stack_args_size;
2158 tree function_result_decl;
2160 rtx first_conversion_insn;
2161 rtx last_conversion_insn;
2162 HOST_WIDE_INT pretend_args_size;
2163 HOST_WIDE_INT extra_pretend_bytes;
2164 int reg_parm_stack_space;
2167 struct assign_parm_data_one
2173 enum machine_mode nominal_mode;
2174 enum machine_mode passed_mode;
2175 enum machine_mode promoted_mode;
2176 struct locate_and_pad_arg_data locate;
2178 BOOL_BITFIELD named_arg : 1;
2179 BOOL_BITFIELD passed_pointer : 1;
2180 BOOL_BITFIELD on_stack : 1;
2181 BOOL_BITFIELD loaded_in_reg : 1;
2184 /* A subroutine of assign_parms. Initialize ALL. */
2187 assign_parms_initialize_all (struct assign_parm_data_all *all)
2189 tree fntype ATTRIBUTE_UNUSED;
2191 memset (all, 0, sizeof (*all));
2193 fntype = TREE_TYPE (current_function_decl);
2195 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
2196 INIT_CUMULATIVE_INCOMING_ARGS (all->args_so_far_v, fntype, NULL_RTX);
2198 INIT_CUMULATIVE_ARGS (all->args_so_far_v, fntype, NULL_RTX,
2199 current_function_decl, -1);
2201 all->args_so_far = pack_cumulative_args (&all->args_so_far_v);
2203 #ifdef REG_PARM_STACK_SPACE
2204 all->reg_parm_stack_space = REG_PARM_STACK_SPACE (current_function_decl);
2208 /* If ARGS contains entries with complex types, split the entry into two
2209 entries of the component type. Return a new list of substitutions are
2210 needed, else the old list. */
2213 split_complex_args (VEC(tree, heap) **args)
2218 FOR_EACH_VEC_ELT (tree, *args, i, p)
2220 tree type = TREE_TYPE (p);
2221 if (TREE_CODE (type) == COMPLEX_TYPE
2222 && targetm.calls.split_complex_arg (type))
2225 tree subtype = TREE_TYPE (type);
2226 bool addressable = TREE_ADDRESSABLE (p);
2228 /* Rewrite the PARM_DECL's type with its component. */
2230 TREE_TYPE (p) = subtype;
2231 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
2232 DECL_MODE (p) = VOIDmode;
2233 DECL_SIZE (p) = NULL;
2234 DECL_SIZE_UNIT (p) = NULL;
2235 /* If this arg must go in memory, put it in a pseudo here.
2236 We can't allow it to go in memory as per normal parms,
2237 because the usual place might not have the imag part
2238 adjacent to the real part. */
2239 DECL_ARTIFICIAL (p) = addressable;
2240 DECL_IGNORED_P (p) = addressable;
2241 TREE_ADDRESSABLE (p) = 0;
2243 VEC_replace (tree, *args, i, p);
2245 /* Build a second synthetic decl. */
2246 decl = build_decl (EXPR_LOCATION (p),
2247 PARM_DECL, NULL_TREE, subtype);
2248 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
2249 DECL_ARTIFICIAL (decl) = addressable;
2250 DECL_IGNORED_P (decl) = addressable;
2251 layout_decl (decl, 0);
2252 VEC_safe_insert (tree, heap, *args, ++i, decl);
2257 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
2258 the hidden struct return argument, and (abi willing) complex args.
2259 Return the new parameter list. */
2261 static VEC(tree, heap) *
2262 assign_parms_augmented_arg_list (struct assign_parm_data_all *all)
2264 tree fndecl = current_function_decl;
2265 tree fntype = TREE_TYPE (fndecl);
2266 VEC(tree, heap) *fnargs = NULL;
2269 for (arg = DECL_ARGUMENTS (fndecl); arg; arg = DECL_CHAIN (arg))
2270 VEC_safe_push (tree, heap, fnargs, arg);
2272 all->orig_fnargs = DECL_ARGUMENTS (fndecl);
2274 /* If struct value address is treated as the first argument, make it so. */
2275 if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
2276 && ! cfun->returns_pcc_struct
2277 && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
2279 tree type = build_pointer_type (TREE_TYPE (fntype));
2282 decl = build_decl (DECL_SOURCE_LOCATION (fndecl),
2283 PARM_DECL, get_identifier (".result_ptr"), type);
2284 DECL_ARG_TYPE (decl) = type;
2285 DECL_ARTIFICIAL (decl) = 1;
2286 DECL_NAMELESS (decl) = 1;
2287 TREE_CONSTANT (decl) = 1;
2289 DECL_CHAIN (decl) = all->orig_fnargs;
2290 all->orig_fnargs = decl;
2291 VEC_safe_insert (tree, heap, fnargs, 0, decl);
2293 all->function_result_decl = decl;
2296 /* If the target wants to split complex arguments into scalars, do so. */
2297 if (targetm.calls.split_complex_arg)
2298 split_complex_args (&fnargs);
2303 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2304 data for the parameter. Incorporate ABI specifics such as pass-by-
2305 reference and type promotion. */
2308 assign_parm_find_data_types (struct assign_parm_data_all *all, tree parm,
2309 struct assign_parm_data_one *data)
2311 tree nominal_type, passed_type;
2312 enum machine_mode nominal_mode, passed_mode, promoted_mode;
2315 memset (data, 0, sizeof (*data));
2317 /* NAMED_ARG is a misnomer. We really mean 'non-variadic'. */
2319 data->named_arg = 1; /* No variadic parms. */
2320 else if (DECL_CHAIN (parm))
2321 data->named_arg = 1; /* Not the last non-variadic parm. */
2322 else if (targetm.calls.strict_argument_naming (all->args_so_far))
2323 data->named_arg = 1; /* Only variadic ones are unnamed. */
2325 data->named_arg = 0; /* Treat as variadic. */
2327 nominal_type = TREE_TYPE (parm);
2328 passed_type = DECL_ARG_TYPE (parm);
2330 /* Look out for errors propagating this far. Also, if the parameter's
2331 type is void then its value doesn't matter. */
2332 if (TREE_TYPE (parm) == error_mark_node
2333 /* This can happen after weird syntax errors
2334 or if an enum type is defined among the parms. */
2335 || TREE_CODE (parm) != PARM_DECL
2336 || passed_type == NULL
2337 || VOID_TYPE_P (nominal_type))
2339 nominal_type = passed_type = void_type_node;
2340 nominal_mode = passed_mode = promoted_mode = VOIDmode;
2344 /* Find mode of arg as it is passed, and mode of arg as it should be
2345 during execution of this function. */
2346 passed_mode = TYPE_MODE (passed_type);
2347 nominal_mode = TYPE_MODE (nominal_type);
2349 /* If the parm is to be passed as a transparent union or record, use the
2350 type of the first field for the tests below. We have already verified
2351 that the modes are the same. */
2352 if ((TREE_CODE (passed_type) == UNION_TYPE
2353 || TREE_CODE (passed_type) == RECORD_TYPE)
2354 && TYPE_TRANSPARENT_AGGR (passed_type))
2355 passed_type = TREE_TYPE (first_field (passed_type));
2357 /* See if this arg was passed by invisible reference. */
2358 if (pass_by_reference (&all->args_so_far_v, passed_mode,
2359 passed_type, data->named_arg))
2361 passed_type = nominal_type = build_pointer_type (passed_type);
2362 data->passed_pointer = true;
2363 passed_mode = nominal_mode = Pmode;
2366 /* Find mode as it is passed by the ABI. */
2367 unsignedp = TYPE_UNSIGNED (passed_type);
2368 promoted_mode = promote_function_mode (passed_type, passed_mode, &unsignedp,
2369 TREE_TYPE (current_function_decl), 0);
2372 data->nominal_type = nominal_type;
2373 data->passed_type = passed_type;
2374 data->nominal_mode = nominal_mode;
2375 data->passed_mode = passed_mode;
2376 data->promoted_mode = promoted_mode;
2379 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2382 assign_parms_setup_varargs (struct assign_parm_data_all *all,
2383 struct assign_parm_data_one *data, bool no_rtl)
2385 int varargs_pretend_bytes = 0;
2387 targetm.calls.setup_incoming_varargs (all->args_so_far,
2388 data->promoted_mode,
2390 &varargs_pretend_bytes, no_rtl);
2392 /* If the back-end has requested extra stack space, record how much is
2393 needed. Do not change pretend_args_size otherwise since it may be
2394 nonzero from an earlier partial argument. */
2395 if (varargs_pretend_bytes > 0)
2396 all->pretend_args_size = varargs_pretend_bytes;
2399 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2400 the incoming location of the current parameter. */
2403 assign_parm_find_entry_rtl (struct assign_parm_data_all *all,
2404 struct assign_parm_data_one *data)
2406 HOST_WIDE_INT pretend_bytes = 0;
2410 if (data->promoted_mode == VOIDmode)
2412 data->entry_parm = data->stack_parm = const0_rtx;
2416 entry_parm = targetm.calls.function_incoming_arg (all->args_so_far,
2417 data->promoted_mode,
2421 if (entry_parm == 0)
2422 data->promoted_mode = data->passed_mode;
2424 /* Determine parm's home in the stack, in case it arrives in the stack
2425 or we should pretend it did. Compute the stack position and rtx where
2426 the argument arrives and its size.
2428 There is one complexity here: If this was a parameter that would
2429 have been passed in registers, but wasn't only because it is
2430 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2431 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2432 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2433 as it was the previous time. */
2434 in_regs = entry_parm != 0;
2435 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2438 if (!in_regs && !data->named_arg)
2440 if (targetm.calls.pretend_outgoing_varargs_named (all->args_so_far))
2443 tem = targetm.calls.function_incoming_arg (all->args_so_far,
2444 data->promoted_mode,
2445 data->passed_type, true);
2446 in_regs = tem != NULL;
2450 /* If this parameter was passed both in registers and in the stack, use
2451 the copy on the stack. */
2452 if (targetm.calls.must_pass_in_stack (data->promoted_mode,
2460 partial = targetm.calls.arg_partial_bytes (all->args_so_far,
2461 data->promoted_mode,
2464 data->partial = partial;
2466 /* The caller might already have allocated stack space for the
2467 register parameters. */
2468 if (partial != 0 && all->reg_parm_stack_space == 0)
2470 /* Part of this argument is passed in registers and part
2471 is passed on the stack. Ask the prologue code to extend
2472 the stack part so that we can recreate the full value.
2474 PRETEND_BYTES is the size of the registers we need to store.
2475 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2476 stack space that the prologue should allocate.
2478 Internally, gcc assumes that the argument pointer is aligned
2479 to STACK_BOUNDARY bits. This is used both for alignment
2480 optimizations (see init_emit) and to locate arguments that are
2481 aligned to more than PARM_BOUNDARY bits. We must preserve this
2482 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2483 a stack boundary. */
2485 /* We assume at most one partial arg, and it must be the first
2486 argument on the stack. */
2487 gcc_assert (!all->extra_pretend_bytes && !all->pretend_args_size);
2489 pretend_bytes = partial;
2490 all->pretend_args_size = CEIL_ROUND (pretend_bytes, STACK_BYTES);
2492 /* We want to align relative to the actual stack pointer, so
2493 don't include this in the stack size until later. */
2494 all->extra_pretend_bytes = all->pretend_args_size;
2498 locate_and_pad_parm (data->promoted_mode, data->passed_type, in_regs,
2499 entry_parm ? data->partial : 0, current_function_decl,
2500 &all->stack_args_size, &data->locate);
2502 /* Update parm_stack_boundary if this parameter is passed in the
2504 if (!in_regs && crtl->parm_stack_boundary < data->locate.boundary)
2505 crtl->parm_stack_boundary = data->locate.boundary;
2507 /* Adjust offsets to include the pretend args. */
2508 pretend_bytes = all->extra_pretend_bytes - pretend_bytes;
2509 data->locate.slot_offset.constant += pretend_bytes;
2510 data->locate.offset.constant += pretend_bytes;
2512 data->entry_parm = entry_parm;
2515 /* A subroutine of assign_parms. If there is actually space on the stack
2516 for this parm, count it in stack_args_size and return true. */
2519 assign_parm_is_stack_parm (struct assign_parm_data_all *all,
2520 struct assign_parm_data_one *data)
2522 /* Trivially true if we've no incoming register. */
2523 if (data->entry_parm == NULL)
2525 /* Also true if we're partially in registers and partially not,
2526 since we've arranged to drop the entire argument on the stack. */
2527 else if (data->partial != 0)
2529 /* Also true if the target says that it's passed in both registers
2530 and on the stack. */
2531 else if (GET_CODE (data->entry_parm) == PARALLEL
2532 && XEXP (XVECEXP (data->entry_parm, 0, 0), 0) == NULL_RTX)
2534 /* Also true if the target says that there's stack allocated for
2535 all register parameters. */
2536 else if (all->reg_parm_stack_space > 0)
2538 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2542 all->stack_args_size.constant += data->locate.size.constant;
2543 if (data->locate.size.var)
2544 ADD_PARM_SIZE (all->stack_args_size, data->locate.size.var);
2549 /* A subroutine of assign_parms. Given that this parameter is allocated
2550 stack space by the ABI, find it. */
2553 assign_parm_find_stack_rtl (tree parm, struct assign_parm_data_one *data)
2555 rtx offset_rtx, stack_parm;
2556 unsigned int align, boundary;
2558 /* If we're passing this arg using a reg, make its stack home the
2559 aligned stack slot. */
2560 if (data->entry_parm)
2561 offset_rtx = ARGS_SIZE_RTX (data->locate.slot_offset);
2563 offset_rtx = ARGS_SIZE_RTX (data->locate.offset);
2565 stack_parm = crtl->args.internal_arg_pointer;
2566 if (offset_rtx != const0_rtx)
2567 stack_parm = gen_rtx_PLUS (Pmode, stack_parm, offset_rtx);
2568 stack_parm = gen_rtx_MEM (data->promoted_mode, stack_parm);
2570 if (!data->passed_pointer)
2572 set_mem_attributes (stack_parm, parm, 1);
2573 /* set_mem_attributes could set MEM_SIZE to the passed mode's size,
2574 while promoted mode's size is needed. */
2575 if (data->promoted_mode != BLKmode
2576 && data->promoted_mode != DECL_MODE (parm))
2578 set_mem_size (stack_parm, GET_MODE_SIZE (data->promoted_mode));
2579 if (MEM_EXPR (stack_parm) && MEM_OFFSET_KNOWN_P (stack_parm))
2581 int offset = subreg_lowpart_offset (DECL_MODE (parm),
2582 data->promoted_mode);
2584 set_mem_offset (stack_parm, MEM_OFFSET (stack_parm) - offset);
2589 boundary = data->locate.boundary;
2590 align = BITS_PER_UNIT;
2592 /* If we're padding upward, we know that the alignment of the slot
2593 is TARGET_FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2594 intentionally forcing upward padding. Otherwise we have to come
2595 up with a guess at the alignment based on OFFSET_RTX. */
2596 if (data->locate.where_pad != downward || data->entry_parm)
2598 else if (CONST_INT_P (offset_rtx))
2600 align = INTVAL (offset_rtx) * BITS_PER_UNIT | boundary;
2601 align = align & -align;
2603 set_mem_align (stack_parm, align);
2605 if (data->entry_parm)
2606 set_reg_attrs_for_parm (data->entry_parm, stack_parm);
2608 data->stack_parm = stack_parm;
2611 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2612 always valid and contiguous. */
2615 assign_parm_adjust_entry_rtl (struct assign_parm_data_one *data)
2617 rtx entry_parm = data->entry_parm;
2618 rtx stack_parm = data->stack_parm;
2620 /* If this parm was passed part in regs and part in memory, pretend it
2621 arrived entirely in memory by pushing the register-part onto the stack.
2622 In the special case of a DImode or DFmode that is split, we could put
2623 it together in a pseudoreg directly, but for now that's not worth
2625 if (data->partial != 0)
2627 /* Handle calls that pass values in multiple non-contiguous
2628 locations. The Irix 6 ABI has examples of this. */
2629 if (GET_CODE (entry_parm) == PARALLEL)
2630 emit_group_store (validize_mem (stack_parm), entry_parm,
2632 int_size_in_bytes (data->passed_type));
2635 gcc_assert (data->partial % UNITS_PER_WORD == 0);
2636 move_block_from_reg (REGNO (entry_parm), validize_mem (stack_parm),
2637 data->partial / UNITS_PER_WORD);
2640 entry_parm = stack_parm;
2643 /* If we didn't decide this parm came in a register, by default it came
2645 else if (entry_parm == NULL)
2646 entry_parm = stack_parm;
2648 /* When an argument is passed in multiple locations, we can't make use
2649 of this information, but we can save some copying if the whole argument
2650 is passed in a single register. */
2651 else if (GET_CODE (entry_parm) == PARALLEL
2652 && data->nominal_mode != BLKmode
2653 && data->passed_mode != BLKmode)
2655 size_t i, len = XVECLEN (entry_parm, 0);
2657 for (i = 0; i < len; i++)
2658 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
2659 && REG_P (XEXP (XVECEXP (entry_parm, 0, i), 0))
2660 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
2661 == data->passed_mode)
2662 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
2664 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
2669 data->entry_parm = entry_parm;
2672 /* A subroutine of assign_parms. Reconstitute any values which were
2673 passed in multiple registers and would fit in a single register. */
2676 assign_parm_remove_parallels (struct assign_parm_data_one *data)
2678 rtx entry_parm = data->entry_parm;
2680 /* Convert the PARALLEL to a REG of the same mode as the parallel.
2681 This can be done with register operations rather than on the
2682 stack, even if we will store the reconstituted parameter on the
2684 if (GET_CODE (entry_parm) == PARALLEL && GET_MODE (entry_parm) != BLKmode)
2686 rtx parmreg = gen_reg_rtx (GET_MODE (entry_parm));
2687 emit_group_store (parmreg, entry_parm, data->passed_type,
2688 GET_MODE_SIZE (GET_MODE (entry_parm)));
2689 entry_parm = parmreg;
2692 data->entry_parm = entry_parm;
2695 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2696 always valid and properly aligned. */
2699 assign_parm_adjust_stack_rtl (struct assign_parm_data_one *data)
2701 rtx stack_parm = data->stack_parm;
2703 /* If we can't trust the parm stack slot to be aligned enough for its
2704 ultimate type, don't use that slot after entry. We'll make another
2705 stack slot, if we need one. */
2707 && ((STRICT_ALIGNMENT
2708 && GET_MODE_ALIGNMENT (data->nominal_mode) > MEM_ALIGN (stack_parm))
2709 || (data->nominal_type
2710 && TYPE_ALIGN (data->nominal_type) > MEM_ALIGN (stack_parm)
2711 && MEM_ALIGN (stack_parm) < PREFERRED_STACK_BOUNDARY)))
2714 /* If parm was passed in memory, and we need to convert it on entry,
2715 don't store it back in that same slot. */
2716 else if (data->entry_parm == stack_parm
2717 && data->nominal_mode != BLKmode
2718 && data->nominal_mode != data->passed_mode)
2721 /* If stack protection is in effect for this function, don't leave any
2722 pointers in their passed stack slots. */
2723 else if (crtl->stack_protect_guard
2724 && (flag_stack_protect == 2
2725 || data->passed_pointer
2726 || POINTER_TYPE_P (data->nominal_type)))
2729 data->stack_parm = stack_parm;
2732 /* A subroutine of assign_parms. Return true if the current parameter
2733 should be stored as a BLKmode in the current frame. */
2736 assign_parm_setup_block_p (struct assign_parm_data_one *data)
2738 if (data->nominal_mode == BLKmode)
2740 if (GET_MODE (data->entry_parm) == BLKmode)
2743 #ifdef BLOCK_REG_PADDING
2744 /* Only assign_parm_setup_block knows how to deal with register arguments
2745 that are padded at the least significant end. */
2746 if (REG_P (data->entry_parm)
2747 && GET_MODE_SIZE (data->promoted_mode) < UNITS_PER_WORD
2748 && (BLOCK_REG_PADDING (data->passed_mode, data->passed_type, 1)
2749 == (BYTES_BIG_ENDIAN ? upward : downward)))
2756 /* A subroutine of assign_parms. Arrange for the parameter to be
2757 present and valid in DATA->STACK_RTL. */
2760 assign_parm_setup_block (struct assign_parm_data_all *all,
2761 tree parm, struct assign_parm_data_one *data)
2763 rtx entry_parm = data->entry_parm;
2764 rtx stack_parm = data->stack_parm;
2766 HOST_WIDE_INT size_stored;
2768 if (GET_CODE (entry_parm) == PARALLEL)
2769 entry_parm = emit_group_move_into_temps (entry_parm);
2771 size = int_size_in_bytes (data->passed_type);
2772 size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
2773 if (stack_parm == 0)
2775 DECL_ALIGN (parm) = MAX (DECL_ALIGN (parm), BITS_PER_WORD);
2776 stack_parm = assign_stack_local (BLKmode, size_stored,
2778 if (GET_MODE_SIZE (GET_MODE (entry_parm)) == size)
2779 PUT_MODE (stack_parm, GET_MODE (entry_parm));
2780 set_mem_attributes (stack_parm, parm, 1);
2783 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2784 calls that pass values in multiple non-contiguous locations. */
2785 if (REG_P (entry_parm) || GET_CODE (entry_parm) == PARALLEL)
2789 /* Note that we will be storing an integral number of words.
2790 So we have to be careful to ensure that we allocate an
2791 integral number of words. We do this above when we call
2792 assign_stack_local if space was not allocated in the argument
2793 list. If it was, this will not work if PARM_BOUNDARY is not
2794 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2795 if it becomes a problem. Exception is when BLKmode arrives
2796 with arguments not conforming to word_mode. */
2798 if (data->stack_parm == 0)
2800 else if (GET_CODE (entry_parm) == PARALLEL)
2803 gcc_assert (!size || !(PARM_BOUNDARY % BITS_PER_WORD));
2805 mem = validize_mem (stack_parm);
2807 /* Handle values in multiple non-contiguous locations. */
2808 if (GET_CODE (entry_parm) == PARALLEL)
2810 push_to_sequence2 (all->first_conversion_insn,
2811 all->last_conversion_insn);
2812 emit_group_store (mem, entry_parm, data->passed_type, size);
2813 all->first_conversion_insn = get_insns ();
2814 all->last_conversion_insn = get_last_insn ();
2821 /* If SIZE is that of a mode no bigger than a word, just use
2822 that mode's store operation. */
2823 else if (size <= UNITS_PER_WORD)
2825 enum machine_mode mode
2826 = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
2829 #ifdef BLOCK_REG_PADDING
2830 && (size == UNITS_PER_WORD
2831 || (BLOCK_REG_PADDING (mode, data->passed_type, 1)
2832 != (BYTES_BIG_ENDIAN ? upward : downward)))
2838 /* We are really truncating a word_mode value containing
2839 SIZE bytes into a value of mode MODE. If such an
2840 operation requires no actual instructions, we can refer
2841 to the value directly in mode MODE, otherwise we must
2842 start with the register in word_mode and explicitly
2844 if (TRULY_NOOP_TRUNCATION (size * BITS_PER_UNIT, BITS_PER_WORD))
2845 reg = gen_rtx_REG (mode, REGNO (entry_parm));
2848 reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
2849 reg = convert_to_mode (mode, copy_to_reg (reg), 1);
2851 emit_move_insn (change_address (mem, mode, 0), reg);
2854 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
2855 machine must be aligned to the left before storing
2856 to memory. Note that the previous test doesn't
2857 handle all cases (e.g. SIZE == 3). */
2858 else if (size != UNITS_PER_WORD
2859 #ifdef BLOCK_REG_PADDING
2860 && (BLOCK_REG_PADDING (mode, data->passed_type, 1)
2868 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2869 rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
2871 x = expand_shift (LSHIFT_EXPR, word_mode, reg, by, NULL_RTX, 1);
2872 tem = change_address (mem, word_mode, 0);
2873 emit_move_insn (tem, x);
2876 move_block_from_reg (REGNO (entry_parm), mem,
2877 size_stored / UNITS_PER_WORD);
2880 move_block_from_reg (REGNO (entry_parm), mem,
2881 size_stored / UNITS_PER_WORD);
2883 else if (data->stack_parm == 0)
2885 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
2886 emit_block_move (stack_parm, data->entry_parm, GEN_INT (size),
2888 all->first_conversion_insn = get_insns ();
2889 all->last_conversion_insn = get_last_insn ();
2893 data->stack_parm = stack_parm;
2894 SET_DECL_RTL (parm, stack_parm);
2897 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
2898 parameter. Get it there. Perform all ABI specified conversions. */
2901 assign_parm_setup_reg (struct assign_parm_data_all *all, tree parm,
2902 struct assign_parm_data_one *data)
2904 rtx parmreg, validated_mem;
2905 rtx equiv_stack_parm;
2906 enum machine_mode promoted_nominal_mode;
2907 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (parm));
2908 bool did_conversion = false;
2909 bool need_conversion, moved;
2911 /* Store the parm in a pseudoregister during the function, but we may
2912 need to do it in a wider mode. Using 2 here makes the result
2913 consistent with promote_decl_mode and thus expand_expr_real_1. */
2914 promoted_nominal_mode
2915 = promote_function_mode (data->nominal_type, data->nominal_mode, &unsignedp,
2916 TREE_TYPE (current_function_decl), 2);
2918 parmreg = gen_reg_rtx (promoted_nominal_mode);
2920 if (!DECL_ARTIFICIAL (parm))
2921 mark_user_reg (parmreg);
2923 /* If this was an item that we received a pointer to,
2924 set DECL_RTL appropriately. */
2925 if (data->passed_pointer)
2927 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data->passed_type)), parmreg);
2928 set_mem_attributes (x, parm, 1);
2929 SET_DECL_RTL (parm, x);
2932 SET_DECL_RTL (parm, parmreg);
2934 assign_parm_remove_parallels (data);
2936 /* Copy the value into the register, thus bridging between
2937 assign_parm_find_data_types and expand_expr_real_1. */
2939 equiv_stack_parm = data->stack_parm;
2940 validated_mem = validize_mem (data->entry_parm);
2942 need_conversion = (data->nominal_mode != data->passed_mode
2943 || promoted_nominal_mode != data->promoted_mode);
2947 && GET_MODE_CLASS (data->nominal_mode) == MODE_INT
2948 && data->nominal_mode == data->passed_mode
2949 && data->nominal_mode == GET_MODE (data->entry_parm))
2951 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
2952 mode, by the caller. We now have to convert it to
2953 NOMINAL_MODE, if different. However, PARMREG may be in
2954 a different mode than NOMINAL_MODE if it is being stored
2957 If ENTRY_PARM is a hard register, it might be in a register
2958 not valid for operating in its mode (e.g., an odd-numbered
2959 register for a DFmode). In that case, moves are the only
2960 thing valid, so we can't do a convert from there. This
2961 occurs when the calling sequence allow such misaligned
2964 In addition, the conversion may involve a call, which could
2965 clobber parameters which haven't been copied to pseudo
2968 First, we try to emit an insn which performs the necessary
2969 conversion. We verify that this insn does not clobber any
2972 enum insn_code icode;
2975 icode = can_extend_p (promoted_nominal_mode, data->passed_mode,
2979 op1 = validated_mem;
2980 if (icode != CODE_FOR_nothing
2981 && insn_operand_matches (icode, 0, op0)
2982 && insn_operand_matches (icode, 1, op1))
2984 enum rtx_code code = unsignedp ? ZERO_EXTEND : SIGN_EXTEND;
2986 HARD_REG_SET hardregs;
2989 insn = gen_extend_insn (op0, op1, promoted_nominal_mode,
2990 data->passed_mode, unsignedp);
2992 insns = get_insns ();
2995 CLEAR_HARD_REG_SET (hardregs);
2996 for (insn = insns; insn && moved; insn = NEXT_INSN (insn))
2999 note_stores (PATTERN (insn), record_hard_reg_sets,
3001 if (!hard_reg_set_empty_p (hardregs))
3010 if (equiv_stack_parm != NULL_RTX)
3011 equiv_stack_parm = gen_rtx_fmt_e (code, GET_MODE (parmreg),
3018 /* Nothing to do. */
3020 else if (need_conversion)
3022 /* We did not have an insn to convert directly, or the sequence
3023 generated appeared unsafe. We must first copy the parm to a
3024 pseudo reg, and save the conversion until after all
3025 parameters have been moved. */
3028 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
3030 emit_move_insn (tempreg, validated_mem);
3032 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
3033 tempreg = convert_to_mode (data->nominal_mode, tempreg, unsignedp);
3035 if (GET_CODE (tempreg) == SUBREG
3036 && GET_MODE (tempreg) == data->nominal_mode
3037 && REG_P (SUBREG_REG (tempreg))
3038 && data->nominal_mode == data->passed_mode
3039 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (data->entry_parm)
3040 && GET_MODE_SIZE (GET_MODE (tempreg))
3041 < GET_MODE_SIZE (GET_MODE (data->entry_parm)))
3043 /* The argument is already sign/zero extended, so note it
3045 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
3046 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
3049 /* TREE_USED gets set erroneously during expand_assignment. */
3050 save_tree_used = TREE_USED (parm);
3051 expand_assignment (parm, make_tree (data->nominal_type, tempreg), false);
3052 TREE_USED (parm) = save_tree_used;
3053 all->first_conversion_insn = get_insns ();
3054 all->last_conversion_insn = get_last_insn ();
3057 did_conversion = true;
3060 emit_move_insn (parmreg, validated_mem);
3062 /* If we were passed a pointer but the actual value can safely live
3063 in a register, put it in one. */
3064 if (data->passed_pointer
3065 && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
3066 /* If by-reference argument was promoted, demote it. */
3067 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
3068 || use_register_for_decl (parm)))
3070 /* We can't use nominal_mode, because it will have been set to
3071 Pmode above. We must use the actual mode of the parm. */
3072 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
3073 mark_user_reg (parmreg);
3075 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
3077 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
3078 int unsigned_p = TYPE_UNSIGNED (TREE_TYPE (parm));
3080 push_to_sequence2 (all->first_conversion_insn,
3081 all->last_conversion_insn);
3082 emit_move_insn (tempreg, DECL_RTL (parm));
3083 tempreg = convert_to_mode (GET_MODE (parmreg), tempreg, unsigned_p);
3084 emit_move_insn (parmreg, tempreg);
3085 all->first_conversion_insn = get_insns ();
3086 all->last_conversion_insn = get_last_insn ();
3089 did_conversion = true;
3092 emit_move_insn (parmreg, DECL_RTL (parm));
3094 SET_DECL_RTL (parm, parmreg);
3096 /* STACK_PARM is the pointer, not the parm, and PARMREG is
3098 data->stack_parm = NULL;
3101 /* Mark the register as eliminable if we did no conversion and it was
3102 copied from memory at a fixed offset, and the arg pointer was not
3103 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
3104 offset formed an invalid address, such memory-equivalences as we
3105 make here would screw up life analysis for it. */
3106 if (data->nominal_mode == data->passed_mode
3108 && data->stack_parm != 0
3109 && MEM_P (data->stack_parm)
3110 && data->locate.offset.var == 0
3111 && reg_mentioned_p (virtual_incoming_args_rtx,
3112 XEXP (data->stack_parm, 0)))
3114 rtx linsn = get_last_insn ();
3117 /* Mark complex types separately. */
3118 if (GET_CODE (parmreg) == CONCAT)
3120 enum machine_mode submode
3121 = GET_MODE_INNER (GET_MODE (parmreg));
3122 int regnor = REGNO (XEXP (parmreg, 0));
3123 int regnoi = REGNO (XEXP (parmreg, 1));
3124 rtx stackr = adjust_address_nv (data->stack_parm, submode, 0);
3125 rtx stacki = adjust_address_nv (data->stack_parm, submode,
3126 GET_MODE_SIZE (submode));
3128 /* Scan backwards for the set of the real and
3130 for (sinsn = linsn; sinsn != 0;
3131 sinsn = prev_nonnote_insn (sinsn))
3133 set = single_set (sinsn);
3137 if (SET_DEST (set) == regno_reg_rtx [regnoi])
3138 set_unique_reg_note (sinsn, REG_EQUIV, stacki);
3139 else if (SET_DEST (set) == regno_reg_rtx [regnor])
3140 set_unique_reg_note (sinsn, REG_EQUIV, stackr);
3143 else if ((set = single_set (linsn)) != 0
3144 && SET_DEST (set) == parmreg)
3145 set_unique_reg_note (linsn, REG_EQUIV, equiv_stack_parm);
3148 /* For pointer data type, suggest pointer register. */
3149 if (POINTER_TYPE_P (TREE_TYPE (parm)))
3150 mark_reg_pointer (parmreg,
3151 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
3154 /* A subroutine of assign_parms. Allocate stack space to hold the current
3155 parameter. Get it there. Perform all ABI specified conversions. */
3158 assign_parm_setup_stack (struct assign_parm_data_all *all, tree parm,
3159 struct assign_parm_data_one *data)
3161 /* Value must be stored in the stack slot STACK_PARM during function
3163 bool to_conversion = false;
3165 assign_parm_remove_parallels (data);
3167 if (data->promoted_mode != data->nominal_mode)
3169 /* Conversion is required. */
3170 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
3172 emit_move_insn (tempreg, validize_mem (data->entry_parm));
3174 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
3175 to_conversion = true;
3177 data->entry_parm = convert_to_mode (data->nominal_mode, tempreg,
3178 TYPE_UNSIGNED (TREE_TYPE (parm)));
3180 if (data->stack_parm)
3182 int offset = subreg_lowpart_offset (data->nominal_mode,
3183 GET_MODE (data->stack_parm));
3184 /* ??? This may need a big-endian conversion on sparc64. */
3186 = adjust_address (data->stack_parm, data->nominal_mode, 0);
3187 if (offset && MEM_OFFSET_KNOWN_P (data->stack_parm))
3188 set_mem_offset (data->stack_parm,
3189 MEM_OFFSET (data->stack_parm) + offset);
3193 if (data->entry_parm != data->stack_parm)
3197 if (data->stack_parm == 0)
3199 int align = STACK_SLOT_ALIGNMENT (data->passed_type,
3200 GET_MODE (data->entry_parm),
3201 TYPE_ALIGN (data->passed_type));
3203 = assign_stack_local (GET_MODE (data->entry_parm),
3204 GET_MODE_SIZE (GET_MODE (data->entry_parm)),
3206 set_mem_attributes (data->stack_parm, parm, 1);
3209 dest = validize_mem (data->stack_parm);
3210 src = validize_mem (data->entry_parm);
3214 /* Use a block move to handle potentially misaligned entry_parm. */
3216 push_to_sequence2 (all->first_conversion_insn,
3217 all->last_conversion_insn);
3218 to_conversion = true;
3220 emit_block_move (dest, src,
3221 GEN_INT (int_size_in_bytes (data->passed_type)),
3225 emit_move_insn (dest, src);
3230 all->first_conversion_insn = get_insns ();
3231 all->last_conversion_insn = get_last_insn ();
3235 SET_DECL_RTL (parm, data->stack_parm);
3238 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
3239 undo the frobbing that we did in assign_parms_augmented_arg_list. */
3242 assign_parms_unsplit_complex (struct assign_parm_data_all *all,
3243 VEC(tree, heap) *fnargs)
3246 tree orig_fnargs = all->orig_fnargs;
3249 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm), ++i)
3251 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE
3252 && targetm.calls.split_complex_arg (TREE_TYPE (parm)))
3254 rtx tmp, real, imag;
3255 enum machine_mode inner = GET_MODE_INNER (DECL_MODE (parm));
3257 real = DECL_RTL (VEC_index (tree, fnargs, i));
3258 imag = DECL_RTL (VEC_index (tree, fnargs, i + 1));
3259 if (inner != GET_MODE (real))
3261 real = gen_lowpart_SUBREG (inner, real);
3262 imag = gen_lowpart_SUBREG (inner, imag);
3265 if (TREE_ADDRESSABLE (parm))
3268 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (parm));
3269 int align = STACK_SLOT_ALIGNMENT (TREE_TYPE (parm),
3271 TYPE_ALIGN (TREE_TYPE (parm)));
3273 /* split_complex_arg put the real and imag parts in
3274 pseudos. Move them to memory. */
3275 tmp = assign_stack_local (DECL_MODE (parm), size, align);
3276 set_mem_attributes (tmp, parm, 1);
3277 rmem = adjust_address_nv (tmp, inner, 0);
3278 imem = adjust_address_nv (tmp, inner, GET_MODE_SIZE (inner));
3279 push_to_sequence2 (all->first_conversion_insn,
3280 all->last_conversion_insn);
3281 emit_move_insn (rmem, real);
3282 emit_move_insn (imem, imag);
3283 all->first_conversion_insn = get_insns ();
3284 all->last_conversion_insn = get_last_insn ();
3288 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3289 SET_DECL_RTL (parm, tmp);
3291 real = DECL_INCOMING_RTL (VEC_index (tree, fnargs, i));
3292 imag = DECL_INCOMING_RTL (VEC_index (tree, fnargs, i + 1));
3293 if (inner != GET_MODE (real))
3295 real = gen_lowpart_SUBREG (inner, real);
3296 imag = gen_lowpart_SUBREG (inner, imag);
3298 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3299 set_decl_incoming_rtl (parm, tmp, false);
3305 /* Assign RTL expressions to the function's parameters. This may involve
3306 copying them into registers and using those registers as the DECL_RTL. */
3309 assign_parms (tree fndecl)
3311 struct assign_parm_data_all all;
3313 VEC(tree, heap) *fnargs;
3316 crtl->args.internal_arg_pointer
3317 = targetm.calls.internal_arg_pointer ();
3319 assign_parms_initialize_all (&all);
3320 fnargs = assign_parms_augmented_arg_list (&all);
3322 FOR_EACH_VEC_ELT (tree, fnargs, i, parm)
3324 struct assign_parm_data_one data;
3326 /* Extract the type of PARM; adjust it according to ABI. */
3327 assign_parm_find_data_types (&all, parm, &data);
3329 /* Early out for errors and void parameters. */
3330 if (data.passed_mode == VOIDmode)
3332 SET_DECL_RTL (parm, const0_rtx);
3333 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
3337 /* Estimate stack alignment from parameter alignment. */
3338 if (SUPPORTS_STACK_ALIGNMENT)
3341 = targetm.calls.function_arg_boundary (data.promoted_mode,
3343 align = MINIMUM_ALIGNMENT (data.passed_type, data.promoted_mode,
3345 if (TYPE_ALIGN (data.nominal_type) > align)
3346 align = MINIMUM_ALIGNMENT (data.nominal_type,
3347 TYPE_MODE (data.nominal_type),
3348 TYPE_ALIGN (data.nominal_type));
3349 if (crtl->stack_alignment_estimated < align)
3351 gcc_assert (!crtl->stack_realign_processed);
3352 crtl->stack_alignment_estimated = align;
3356 if (cfun->stdarg && !DECL_CHAIN (parm))
3357 assign_parms_setup_varargs (&all, &data, false);
3359 /* Find out where the parameter arrives in this function. */
3360 assign_parm_find_entry_rtl (&all, &data);
3362 /* Find out where stack space for this parameter might be. */
3363 if (assign_parm_is_stack_parm (&all, &data))
3365 assign_parm_find_stack_rtl (parm, &data);
3366 assign_parm_adjust_entry_rtl (&data);
3369 /* Record permanently how this parm was passed. */
3370 if (data.passed_pointer)
3373 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data.passed_type)),
3375 set_decl_incoming_rtl (parm, incoming_rtl, true);
3378 set_decl_incoming_rtl (parm, data.entry_parm, false);
3380 /* Update info on where next arg arrives in registers. */
3381 targetm.calls.function_arg_advance (all.args_so_far, data.promoted_mode,
3382 data.passed_type, data.named_arg);
3384 assign_parm_adjust_stack_rtl (&data);
3386 if (assign_parm_setup_block_p (&data))
3387 assign_parm_setup_block (&all, parm, &data);
3388 else if (data.passed_pointer || use_register_for_decl (parm))
3389 assign_parm_setup_reg (&all, parm, &data);
3391 assign_parm_setup_stack (&all, parm, &data);
3394 if (targetm.calls.split_complex_arg)
3395 assign_parms_unsplit_complex (&all, fnargs);
3397 VEC_free (tree, heap, fnargs);
3399 /* Output all parameter conversion instructions (possibly including calls)
3400 now that all parameters have been copied out of hard registers. */
3401 emit_insn (all.first_conversion_insn);
3403 /* Estimate reload stack alignment from scalar return mode. */
3404 if (SUPPORTS_STACK_ALIGNMENT)
3406 if (DECL_RESULT (fndecl))
3408 tree type = TREE_TYPE (DECL_RESULT (fndecl));
3409 enum machine_mode mode = TYPE_MODE (type);
3413 && !AGGREGATE_TYPE_P (type))
3415 unsigned int align = GET_MODE_ALIGNMENT (mode);
3416 if (crtl->stack_alignment_estimated < align)
3418 gcc_assert (!crtl->stack_realign_processed);
3419 crtl->stack_alignment_estimated = align;
3425 /* If we are receiving a struct value address as the first argument, set up
3426 the RTL for the function result. As this might require code to convert
3427 the transmitted address to Pmode, we do this here to ensure that possible
3428 preliminary conversions of the address have been emitted already. */
3429 if (all.function_result_decl)
3431 tree result = DECL_RESULT (current_function_decl);
3432 rtx addr = DECL_RTL (all.function_result_decl);
3435 if (DECL_BY_REFERENCE (result))
3437 SET_DECL_VALUE_EXPR (result, all.function_result_decl);
3442 SET_DECL_VALUE_EXPR (result,
3443 build1 (INDIRECT_REF, TREE_TYPE (result),
3444 all.function_result_decl));
3445 addr = convert_memory_address (Pmode, addr);
3446 x = gen_rtx_MEM (DECL_MODE (result), addr);
3447 set_mem_attributes (x, result, 1);
3450 DECL_HAS_VALUE_EXPR_P (result) = 1;
3452 SET_DECL_RTL (result, x);
3455 /* We have aligned all the args, so add space for the pretend args. */
3456 crtl->args.pretend_args_size = all.pretend_args_size;
3457 all.stack_args_size.constant += all.extra_pretend_bytes;
3458 crtl->args.size = all.stack_args_size.constant;
3460 /* Adjust function incoming argument size for alignment and
3463 #ifdef REG_PARM_STACK_SPACE
3464 crtl->args.size = MAX (crtl->args.size,
3465 REG_PARM_STACK_SPACE (fndecl));
3468 crtl->args.size = CEIL_ROUND (crtl->args.size,
3469 PARM_BOUNDARY / BITS_PER_UNIT);
3471 #ifdef ARGS_GROW_DOWNWARD
3472 crtl->args.arg_offset_rtx
3473 = (all.stack_args_size.var == 0 ? GEN_INT (-all.stack_args_size.constant)
3474 : expand_expr (size_diffop (all.stack_args_size.var,
3475 size_int (-all.stack_args_size.constant)),
3476 NULL_RTX, VOIDmode, EXPAND_NORMAL));
3478 crtl->args.arg_offset_rtx = ARGS_SIZE_RTX (all.stack_args_size);
3481 /* See how many bytes, if any, of its args a function should try to pop
3484 crtl->args.pops_args = targetm.calls.return_pops_args (fndecl,
3488 /* For stdarg.h function, save info about
3489 regs and stack space used by the named args. */
3491 crtl->args.info = all.args_so_far_v;
3493 /* Set the rtx used for the function return value. Put this in its
3494 own variable so any optimizers that need this information don't have
3495 to include tree.h. Do this here so it gets done when an inlined
3496 function gets output. */
3499 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
3500 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
3502 /* If scalar return value was computed in a pseudo-reg, or was a named
3503 return value that got dumped to the stack, copy that to the hard
3505 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
3507 tree decl_result = DECL_RESULT (fndecl);
3508 rtx decl_rtl = DECL_RTL (decl_result);
3510 if (REG_P (decl_rtl)
3511 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
3512 : DECL_REGISTER (decl_result))
3516 real_decl_rtl = targetm.calls.function_value (TREE_TYPE (decl_result),
3518 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
3519 /* The delay slot scheduler assumes that crtl->return_rtx
3520 holds the hard register containing the return value, not a
3521 temporary pseudo. */
3522 crtl->return_rtx = real_decl_rtl;
3527 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3528 For all seen types, gimplify their sizes. */
3531 gimplify_parm_type (tree *tp, int *walk_subtrees, void *data)
3538 if (POINTER_TYPE_P (t))
3540 else if (TYPE_SIZE (t) && !TREE_CONSTANT (TYPE_SIZE (t))
3541 && !TYPE_SIZES_GIMPLIFIED (t))
3543 gimplify_type_sizes (t, (gimple_seq *) data);
3551 /* Gimplify the parameter list for current_function_decl. This involves
3552 evaluating SAVE_EXPRs of variable sized parameters and generating code
3553 to implement callee-copies reference parameters. Returns a sequence of
3554 statements to add to the beginning of the function. */
3557 gimplify_parameters (void)
3559 struct assign_parm_data_all all;
3561 gimple_seq stmts = NULL;
3562 VEC(tree, heap) *fnargs;
3565 assign_parms_initialize_all (&all);
3566 fnargs = assign_parms_augmented_arg_list (&all);
3568 FOR_EACH_VEC_ELT (tree, fnargs, i, parm)
3570 struct assign_parm_data_one data;
3572 /* Extract the type of PARM; adjust it according to ABI. */
3573 assign_parm_find_data_types (&all, parm, &data);
3575 /* Early out for errors and void parameters. */
3576 if (data.passed_mode == VOIDmode || DECL_SIZE (parm) == NULL)
3579 /* Update info on where next arg arrives in registers. */
3580 targetm.calls.function_arg_advance (all.args_so_far, data.promoted_mode,
3581 data.passed_type, data.named_arg);
3583 /* ??? Once upon a time variable_size stuffed parameter list
3584 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3585 turned out to be less than manageable in the gimple world.
3586 Now we have to hunt them down ourselves. */
3587 walk_tree_without_duplicates (&data.passed_type,
3588 gimplify_parm_type, &stmts);
3590 if (TREE_CODE (DECL_SIZE_UNIT (parm)) != INTEGER_CST)
3592 gimplify_one_sizepos (&DECL_SIZE (parm), &stmts);
3593 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm), &stmts);
3596 if (data.passed_pointer)
3598 tree type = TREE_TYPE (data.passed_type);
3599 if (reference_callee_copied (&all.args_so_far_v, TYPE_MODE (type),
3600 type, data.named_arg))
3604 /* For constant-sized objects, this is trivial; for
3605 variable-sized objects, we have to play games. */
3606 if (TREE_CODE (DECL_SIZE_UNIT (parm)) == INTEGER_CST
3607 && !(flag_stack_check == GENERIC_STACK_CHECK
3608 && compare_tree_int (DECL_SIZE_UNIT (parm),
3609 STACK_CHECK_MAX_VAR_SIZE) > 0))
3611 local = create_tmp_var (type, get_name (parm));
3612 DECL_IGNORED_P (local) = 0;
3613 /* If PARM was addressable, move that flag over
3614 to the local copy, as its address will be taken,
3615 not the PARMs. Keep the parms address taken
3616 as we'll query that flag during gimplification. */
3617 if (TREE_ADDRESSABLE (parm))
3618 TREE_ADDRESSABLE (local) = 1;
3619 else if (TREE_CODE (type) == COMPLEX_TYPE
3620 || TREE_CODE (type) == VECTOR_TYPE)
3621 DECL_GIMPLE_REG_P (local) = 1;
3625 tree ptr_type, addr;
3627 ptr_type = build_pointer_type (type);
3628 addr = create_tmp_reg (ptr_type, get_name (parm));
3629 DECL_IGNORED_P (addr) = 0;
3630 local = build_fold_indirect_ref (addr);
3632 t = builtin_decl_explicit (BUILT_IN_ALLOCA_WITH_ALIGN);
3633 t = build_call_expr (t, 2, DECL_SIZE_UNIT (parm),
3634 size_int (DECL_ALIGN (parm)));
3636 /* The call has been built for a variable-sized object. */
3637 CALL_ALLOCA_FOR_VAR_P (t) = 1;
3638 t = fold_convert (ptr_type, t);
3639 t = build2 (MODIFY_EXPR, TREE_TYPE (addr), addr, t);
3640 gimplify_and_add (t, &stmts);
3643 gimplify_assign (local, parm, &stmts);
3645 SET_DECL_VALUE_EXPR (parm, local);
3646 DECL_HAS_VALUE_EXPR_P (parm) = 1;
3651 VEC_free (tree, heap, fnargs);
3656 /* Compute the size and offset from the start of the stacked arguments for a
3657 parm passed in mode PASSED_MODE and with type TYPE.
3659 INITIAL_OFFSET_PTR points to the current offset into the stacked
3662 The starting offset and size for this parm are returned in
3663 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3664 nonzero, the offset is that of stack slot, which is returned in
3665 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3666 padding required from the initial offset ptr to the stack slot.
3668 IN_REGS is nonzero if the argument will be passed in registers. It will
3669 never be set if REG_PARM_STACK_SPACE is not defined.
3671 FNDECL is the function in which the argument was defined.
3673 There are two types of rounding that are done. The first, controlled by
3674 TARGET_FUNCTION_ARG_BOUNDARY, forces the offset from the start of the
3675 argument list to be aligned to the specific boundary (in bits). This
3676 rounding affects the initial and starting offsets, but not the argument
3679 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3680 optionally rounds the size of the parm to PARM_BOUNDARY. The
3681 initial offset is not affected by this rounding, while the size always
3682 is and the starting offset may be. */
3684 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3685 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3686 callers pass in the total size of args so far as
3687 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
3690 locate_and_pad_parm (enum machine_mode passed_mode, tree type, int in_regs,
3691 int partial, tree fndecl ATTRIBUTE_UNUSED,
3692 struct args_size *initial_offset_ptr,
3693 struct locate_and_pad_arg_data *locate)
3696 enum direction where_pad;
3697 unsigned int boundary, round_boundary;
3698 int reg_parm_stack_space = 0;
3699 int part_size_in_regs;
3701 #ifdef REG_PARM_STACK_SPACE
3702 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
3704 /* If we have found a stack parm before we reach the end of the
3705 area reserved for registers, skip that area. */
3708 if (reg_parm_stack_space > 0)
3710 if (initial_offset_ptr->var)
3712 initial_offset_ptr->var
3713 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
3714 ssize_int (reg_parm_stack_space));
3715 initial_offset_ptr->constant = 0;
3717 else if (initial_offset_ptr->constant < reg_parm_stack_space)
3718 initial_offset_ptr->constant = reg_parm_stack_space;
3721 #endif /* REG_PARM_STACK_SPACE */
3723 part_size_in_regs = (reg_parm_stack_space == 0 ? partial : 0);
3726 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
3727 where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
3728 boundary = targetm.calls.function_arg_boundary (passed_mode, type);
3729 round_boundary = targetm.calls.function_arg_round_boundary (passed_mode,
3731 locate->where_pad = where_pad;
3733 /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT. */
3734 if (boundary > MAX_SUPPORTED_STACK_ALIGNMENT)
3735 boundary = MAX_SUPPORTED_STACK_ALIGNMENT;
3737 locate->boundary = boundary;
3739 if (SUPPORTS_STACK_ALIGNMENT)
3741 /* stack_alignment_estimated can't change after stack has been
3743 if (crtl->stack_alignment_estimated < boundary)
3745 if (!crtl->stack_realign_processed)
3746 crtl->stack_alignment_estimated = boundary;
3749 /* If stack is realigned and stack alignment value
3750 hasn't been finalized, it is OK not to increase
3751 stack_alignment_estimated. The bigger alignment
3752 requirement is recorded in stack_alignment_needed
3754 gcc_assert (!crtl->stack_realign_finalized
3755 && crtl->stack_realign_needed);
3760 /* Remember if the outgoing parameter requires extra alignment on the
3761 calling function side. */
3762 if (crtl->stack_alignment_needed < boundary)
3763 crtl->stack_alignment_needed = boundary;
3764 if (crtl->preferred_stack_boundary < boundary)
3765 crtl->preferred_stack_boundary = boundary;
3767 #ifdef ARGS_GROW_DOWNWARD
3768 locate->slot_offset.constant = -initial_offset_ptr->constant;
3769 if (initial_offset_ptr->var)
3770 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
3771 initial_offset_ptr->var);
3775 if (where_pad != none
3776 && (!host_integerp (sizetree, 1)
3777 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % round_boundary))
3778 s2 = round_up (s2, round_boundary / BITS_PER_UNIT);
3779 SUB_PARM_SIZE (locate->slot_offset, s2);
3782 locate->slot_offset.constant += part_size_in_regs;
3785 #ifdef REG_PARM_STACK_SPACE
3786 || REG_PARM_STACK_SPACE (fndecl) > 0
3789 pad_to_arg_alignment (&locate->slot_offset, boundary,
3790 &locate->alignment_pad);
3792 locate->size.constant = (-initial_offset_ptr->constant
3793 - locate->slot_offset.constant);
3794 if (initial_offset_ptr->var)
3795 locate->size.var = size_binop (MINUS_EXPR,
3796 size_binop (MINUS_EXPR,
3798 initial_offset_ptr->var),
3799 locate->slot_offset.var);
3801 /* Pad_below needs the pre-rounded size to know how much to pad
3803 locate->offset = locate->slot_offset;
3804 if (where_pad == downward)
3805 pad_below (&locate->offset, passed_mode, sizetree);
3807 #else /* !ARGS_GROW_DOWNWARD */
3809 #ifdef REG_PARM_STACK_SPACE
3810 || REG_PARM_STACK_SPACE (fndecl) > 0
3813 pad_to_arg_alignment (initial_offset_ptr, boundary,
3814 &locate->alignment_pad);
3815 locate->slot_offset = *initial_offset_ptr;
3817 #ifdef PUSH_ROUNDING
3818 if (passed_mode != BLKmode)
3819 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
3822 /* Pad_below needs the pre-rounded size to know how much to pad below
3823 so this must be done before rounding up. */
3824 locate->offset = locate->slot_offset;
3825 if (where_pad == downward)
3826 pad_below (&locate->offset, passed_mode, sizetree);
3828 if (where_pad != none
3829 && (!host_integerp (sizetree, 1)
3830 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % round_boundary))
3831 sizetree = round_up (sizetree, round_boundary / BITS_PER_UNIT);
3833 ADD_PARM_SIZE (locate->size, sizetree);
3835 locate->size.constant -= part_size_in_regs;
3836 #endif /* ARGS_GROW_DOWNWARD */
3838 #ifdef FUNCTION_ARG_OFFSET
3839 locate->offset.constant += FUNCTION_ARG_OFFSET (passed_mode, type);
3843 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
3844 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
3847 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
3848 struct args_size *alignment_pad)
3850 tree save_var = NULL_TREE;
3851 HOST_WIDE_INT save_constant = 0;
3852 int boundary_in_bytes = boundary / BITS_PER_UNIT;
3853 HOST_WIDE_INT sp_offset = STACK_POINTER_OFFSET;
3855 #ifdef SPARC_STACK_BOUNDARY_HACK
3856 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
3857 the real alignment of %sp. However, when it does this, the
3858 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
3859 if (SPARC_STACK_BOUNDARY_HACK)
3863 if (boundary > PARM_BOUNDARY)
3865 save_var = offset_ptr->var;
3866 save_constant = offset_ptr->constant;
3869 alignment_pad->var = NULL_TREE;
3870 alignment_pad->constant = 0;
3872 if (boundary > BITS_PER_UNIT)
3874 if (offset_ptr->var)
3876 tree sp_offset_tree = ssize_int (sp_offset);
3877 tree offset = size_binop (PLUS_EXPR,
3878 ARGS_SIZE_TREE (*offset_ptr),
3880 #ifdef ARGS_GROW_DOWNWARD
3881 tree rounded = round_down (offset, boundary / BITS_PER_UNIT);
3883 tree rounded = round_up (offset, boundary / BITS_PER_UNIT);
3886 offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
3887 /* ARGS_SIZE_TREE includes constant term. */
3888 offset_ptr->constant = 0;
3889 if (boundary > PARM_BOUNDARY)
3890 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
3895 offset_ptr->constant = -sp_offset +
3896 #ifdef ARGS_GROW_DOWNWARD
3897 FLOOR_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
3899 CEIL_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
3901 if (boundary > PARM_BOUNDARY)
3902 alignment_pad->constant = offset_ptr->constant - save_constant;
3908 pad_below (struct args_size *offset_ptr, enum machine_mode passed_mode, tree sizetree)
3910 if (passed_mode != BLKmode)
3912 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
3913 offset_ptr->constant
3914 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
3915 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
3916 - GET_MODE_SIZE (passed_mode));
3920 if (TREE_CODE (sizetree) != INTEGER_CST
3921 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
3923 /* Round the size up to multiple of PARM_BOUNDARY bits. */
3924 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
3926 ADD_PARM_SIZE (*offset_ptr, s2);
3927 SUB_PARM_SIZE (*offset_ptr, sizetree);
3933 /* True if register REGNO was alive at a place where `setjmp' was
3934 called and was set more than once or is an argument. Such regs may
3935 be clobbered by `longjmp'. */
3938 regno_clobbered_at_setjmp (bitmap setjmp_crosses, int regno)
3940 /* There appear to be cases where some local vars never reach the
3941 backend but have bogus regnos. */
3942 if (regno >= max_reg_num ())
3945 return ((REG_N_SETS (regno) > 1
3946 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR), regno))
3947 && REGNO_REG_SET_P (setjmp_crosses, regno));
3950 /* Walk the tree of blocks describing the binding levels within a
3951 function and warn about variables the might be killed by setjmp or
3952 vfork. This is done after calling flow_analysis before register
3953 allocation since that will clobber the pseudo-regs to hard
3957 setjmp_vars_warning (bitmap setjmp_crosses, tree block)
3961 for (decl = BLOCK_VARS (block); decl; decl = DECL_CHAIN (decl))
3963 if (TREE_CODE (decl) == VAR_DECL
3964 && DECL_RTL_SET_P (decl)
3965 && REG_P (DECL_RTL (decl))
3966 && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
3967 warning (OPT_Wclobbered, "variable %q+D might be clobbered by"
3968 " %<longjmp%> or %<vfork%>", decl);
3971 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = BLOCK_CHAIN (sub))
3972 setjmp_vars_warning (setjmp_crosses, sub);
3975 /* Do the appropriate part of setjmp_vars_warning
3976 but for arguments instead of local variables. */
3979 setjmp_args_warning (bitmap setjmp_crosses)
3982 for (decl = DECL_ARGUMENTS (current_function_decl);
3983 decl; decl = DECL_CHAIN (decl))
3984 if (DECL_RTL (decl) != 0
3985 && REG_P (DECL_RTL (decl))
3986 && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
3987 warning (OPT_Wclobbered,
3988 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
3992 /* Generate warning messages for variables live across setjmp. */
3995 generate_setjmp_warnings (void)
3997 bitmap setjmp_crosses = regstat_get_setjmp_crosses ();
3999 if (n_basic_blocks == NUM_FIXED_BLOCKS
4000 || bitmap_empty_p (setjmp_crosses))
4003 setjmp_vars_warning (setjmp_crosses, DECL_INITIAL (current_function_decl));
4004 setjmp_args_warning (setjmp_crosses);
4008 /* Reverse the order of elements in the fragment chain T of blocks,
4009 and return the new head of the chain (old last element). */
4012 block_fragments_nreverse (tree t)
4014 tree prev = 0, block, next;
4015 for (block = t; block; block = next)
4017 next = BLOCK_FRAGMENT_CHAIN (block);
4018 BLOCK_FRAGMENT_CHAIN (block) = prev;
4024 /* Reverse the order of elements in the chain T of blocks,
4025 and return the new head of the chain (old last element).
4026 Also do the same on subblocks and reverse the order of elements
4027 in BLOCK_FRAGMENT_CHAIN as well. */
4030 blocks_nreverse_all (tree t)
4032 tree prev = 0, block, next;
4033 for (block = t; block; block = next)
4035 next = BLOCK_CHAIN (block);
4036 BLOCK_CHAIN (block) = prev;
4037 BLOCK_SUBBLOCKS (block) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block));
4038 if (BLOCK_FRAGMENT_CHAIN (block)
4039 && BLOCK_FRAGMENT_ORIGIN (block) == NULL_TREE)
4040 BLOCK_FRAGMENT_CHAIN (block)
4041 = block_fragments_nreverse (BLOCK_FRAGMENT_CHAIN (block));
4048 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
4049 and create duplicate blocks. */
4050 /* ??? Need an option to either create block fragments or to create
4051 abstract origin duplicates of a source block. It really depends
4052 on what optimization has been performed. */
4055 reorder_blocks (void)
4057 tree block = DECL_INITIAL (current_function_decl);
4058 VEC(tree,heap) *block_stack;
4060 if (block == NULL_TREE)
4063 block_stack = VEC_alloc (tree, heap, 10);
4065 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
4066 clear_block_marks (block);
4068 /* Prune the old trees away, so that they don't get in the way. */
4069 BLOCK_SUBBLOCKS (block) = NULL_TREE;
4070 BLOCK_CHAIN (block) = NULL_TREE;
4072 /* Recreate the block tree from the note nesting. */
4073 reorder_blocks_1 (get_insns (), block, &block_stack);
4074 BLOCK_SUBBLOCKS (block) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block));
4076 VEC_free (tree, heap, block_stack);
4079 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
4082 clear_block_marks (tree block)
4086 TREE_ASM_WRITTEN (block) = 0;
4087 clear_block_marks (BLOCK_SUBBLOCKS (block));
4088 block = BLOCK_CHAIN (block);
4093 reorder_blocks_1 (rtx insns, tree current_block, VEC(tree,heap) **p_block_stack)
4097 for (insn = insns; insn; insn = NEXT_INSN (insn))
4101 if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_BEG)
4103 tree block = NOTE_BLOCK (insn);
4106 gcc_assert (BLOCK_FRAGMENT_ORIGIN (block) == NULL_TREE);
4109 /* If we have seen this block before, that means it now
4110 spans multiple address regions. Create a new fragment. */
4111 if (TREE_ASM_WRITTEN (block))
4113 tree new_block = copy_node (block);
4115 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
4116 BLOCK_FRAGMENT_CHAIN (new_block)
4117 = BLOCK_FRAGMENT_CHAIN (origin);
4118 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
4120 NOTE_BLOCK (insn) = new_block;
4124 BLOCK_SUBBLOCKS (block) = 0;
4125 TREE_ASM_WRITTEN (block) = 1;
4126 /* When there's only one block for the entire function,
4127 current_block == block and we mustn't do this, it
4128 will cause infinite recursion. */
4129 if (block != current_block)
4131 if (block != origin)
4132 gcc_assert (BLOCK_SUPERCONTEXT (origin) == current_block);
4134 BLOCK_SUPERCONTEXT (block) = current_block;
4135 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
4136 BLOCK_SUBBLOCKS (current_block) = block;
4137 current_block = origin;
4139 VEC_safe_push (tree, heap, *p_block_stack, block);
4141 else if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_END)
4143 NOTE_BLOCK (insn) = VEC_pop (tree, *p_block_stack);
4144 current_block = BLOCK_SUPERCONTEXT (current_block);
4150 /* Reverse the order of elements in the chain T of blocks,
4151 and return the new head of the chain (old last element). */
4154 blocks_nreverse (tree t)
4156 tree prev = 0, block, next;
4157 for (block = t; block; block = next)
4159 next = BLOCK_CHAIN (block);
4160 BLOCK_CHAIN (block) = prev;
4166 /* Concatenate two chains of blocks (chained through BLOCK_CHAIN)
4167 by modifying the last node in chain 1 to point to chain 2. */
4170 block_chainon (tree op1, tree op2)
4179 for (t1 = op1; BLOCK_CHAIN (t1); t1 = BLOCK_CHAIN (t1))
4181 BLOCK_CHAIN (t1) = op2;
4183 #ifdef ENABLE_TREE_CHECKING
4186 for (t2 = op2; t2; t2 = BLOCK_CHAIN (t2))
4187 gcc_assert (t2 != t1);
4194 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
4195 non-NULL, list them all into VECTOR, in a depth-first preorder
4196 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
4200 all_blocks (tree block, tree *vector)
4206 TREE_ASM_WRITTEN (block) = 0;
4208 /* Record this block. */
4210 vector[n_blocks] = block;
4214 /* Record the subblocks, and their subblocks... */
4215 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
4216 vector ? vector + n_blocks : 0);
4217 block = BLOCK_CHAIN (block);
4223 /* Return a vector containing all the blocks rooted at BLOCK. The
4224 number of elements in the vector is stored in N_BLOCKS_P. The
4225 vector is dynamically allocated; it is the caller's responsibility
4226 to call `free' on the pointer returned. */
4229 get_block_vector (tree block, int *n_blocks_p)
4233 *n_blocks_p = all_blocks (block, NULL);
4234 block_vector = XNEWVEC (tree, *n_blocks_p);
4235 all_blocks (block, block_vector);
4237 return block_vector;
4240 static GTY(()) int next_block_index = 2;
4242 /* Set BLOCK_NUMBER for all the blocks in FN. */
4245 number_blocks (tree fn)
4251 /* For SDB and XCOFF debugging output, we start numbering the blocks
4252 from 1 within each function, rather than keeping a running
4254 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
4255 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
4256 next_block_index = 1;
4259 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
4261 /* The top-level BLOCK isn't numbered at all. */
4262 for (i = 1; i < n_blocks; ++i)
4263 /* We number the blocks from two. */
4264 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
4266 free (block_vector);
4271 /* If VAR is present in a subblock of BLOCK, return the subblock. */
4274 debug_find_var_in_block_tree (tree var, tree block)
4278 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
4282 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
4284 tree ret = debug_find_var_in_block_tree (var, t);
4292 /* Keep track of whether we're in a dummy function context. If we are,
4293 we don't want to invoke the set_current_function hook, because we'll
4294 get into trouble if the hook calls target_reinit () recursively or
4295 when the initial initialization is not yet complete. */
4297 static bool in_dummy_function;
4299 /* Invoke the target hook when setting cfun. Update the optimization options
4300 if the function uses different options than the default. */
4303 invoke_set_current_function_hook (tree fndecl)
4305 if (!in_dummy_function)
4307 tree opts = ((fndecl)
4308 ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl)
4309 : optimization_default_node);
4312 opts = optimization_default_node;
4314 /* Change optimization options if needed. */
4315 if (optimization_current_node != opts)
4317 optimization_current_node = opts;
4318 cl_optimization_restore (&global_options, TREE_OPTIMIZATION (opts));
4321 targetm.set_current_function (fndecl);
4325 /* cfun should never be set directly; use this function. */
4328 set_cfun (struct function *new_cfun)
4330 if (cfun != new_cfun)
4333 invoke_set_current_function_hook (new_cfun ? new_cfun->decl : NULL_TREE);
4337 /* Initialized with NOGC, making this poisonous to the garbage collector. */
4339 static VEC(function_p,heap) *cfun_stack;
4341 /* Push the current cfun onto the stack, and set cfun to new_cfun. */
4344 push_cfun (struct function *new_cfun)
4346 VEC_safe_push (function_p, heap, cfun_stack, cfun);
4347 set_cfun (new_cfun);
4350 /* Pop cfun from the stack. */
4355 struct function *new_cfun = VEC_pop (function_p, cfun_stack);
4356 set_cfun (new_cfun);
4359 /* Return value of funcdef and increase it. */
4361 get_next_funcdef_no (void)
4363 return funcdef_no++;
4366 /* Return value of funcdef. */
4368 get_last_funcdef_no (void)
4373 /* Allocate a function structure for FNDECL and set its contents
4374 to the defaults. Set cfun to the newly-allocated object.
4375 Some of the helper functions invoked during initialization assume
4376 that cfun has already been set. Therefore, assign the new object
4377 directly into cfun and invoke the back end hook explicitly at the
4378 very end, rather than initializing a temporary and calling set_cfun
4381 ABSTRACT_P is true if this is a function that will never be seen by
4382 the middle-end. Such functions are front-end concepts (like C++
4383 function templates) that do not correspond directly to functions
4384 placed in object files. */
4387 allocate_struct_function (tree fndecl, bool abstract_p)
4390 tree fntype = fndecl ? TREE_TYPE (fndecl) : NULL_TREE;
4392 cfun = ggc_alloc_cleared_function ();
4394 init_eh_for_function ();
4396 if (init_machine_status)
4397 cfun->machine = (*init_machine_status) ();
4399 #ifdef OVERRIDE_ABI_FORMAT
4400 OVERRIDE_ABI_FORMAT (fndecl);
4403 invoke_set_current_function_hook (fndecl);
4405 if (fndecl != NULL_TREE)
4407 DECL_STRUCT_FUNCTION (fndecl) = cfun;
4408 cfun->decl = fndecl;
4409 current_function_funcdef_no = get_next_funcdef_no ();
4411 result = DECL_RESULT (fndecl);
4412 if (!abstract_p && aggregate_value_p (result, fndecl))
4414 #ifdef PCC_STATIC_STRUCT_RETURN
4415 cfun->returns_pcc_struct = 1;
4417 cfun->returns_struct = 1;
4420 cfun->stdarg = stdarg_p (fntype);
4422 /* Assume all registers in stdarg functions need to be saved. */
4423 cfun->va_list_gpr_size = VA_LIST_MAX_GPR_SIZE;
4424 cfun->va_list_fpr_size = VA_LIST_MAX_FPR_SIZE;
4426 /* ??? This could be set on a per-function basis by the front-end
4427 but is this worth the hassle? */
4428 cfun->can_throw_non_call_exceptions = flag_non_call_exceptions;
4432 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
4433 instead of just setting it. */
4436 push_struct_function (tree fndecl)
4438 VEC_safe_push (function_p, heap, cfun_stack, cfun);
4439 allocate_struct_function (fndecl, false);
4442 /* Reset crtl and other non-struct-function variables to defaults as
4443 appropriate for emitting rtl at the start of a function. */
4446 prepare_function_start (void)
4448 gcc_assert (!crtl->emit.x_last_insn);
4451 init_varasm_status ();
4453 default_rtl_profile ();
4455 if (flag_stack_usage_info)
4457 cfun->su = ggc_alloc_cleared_stack_usage ();
4458 cfun->su->static_stack_size = -1;
4461 cse_not_expected = ! optimize;
4463 /* Caller save not needed yet. */
4464 caller_save_needed = 0;
4466 /* We haven't done register allocation yet. */
4469 /* Indicate that we have not instantiated virtual registers yet. */
4470 virtuals_instantiated = 0;
4472 /* Indicate that we want CONCATs now. */
4473 generating_concat_p = 1;
4475 /* Indicate we have no need of a frame pointer yet. */
4476 frame_pointer_needed = 0;
4479 /* Initialize the rtl expansion mechanism so that we can do simple things
4480 like generate sequences. This is used to provide a context during global
4481 initialization of some passes. You must call expand_dummy_function_end
4482 to exit this context. */
4485 init_dummy_function_start (void)
4487 gcc_assert (!in_dummy_function);
4488 in_dummy_function = true;
4489 push_struct_function (NULL_TREE);
4490 prepare_function_start ();
4493 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
4494 and initialize static variables for generating RTL for the statements
4498 init_function_start (tree subr)
4500 if (subr && DECL_STRUCT_FUNCTION (subr))
4501 set_cfun (DECL_STRUCT_FUNCTION (subr));
4503 allocate_struct_function (subr, false);
4504 prepare_function_start ();
4505 decide_function_section (subr);
4507 /* Warn if this value is an aggregate type,
4508 regardless of which calling convention we are using for it. */
4509 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
4510 warning (OPT_Waggregate_return, "function returns an aggregate");
4513 /* Make sure all values used by the optimization passes have sane defaults. */
4515 init_function_for_compilation (void)
4521 struct rtl_opt_pass pass_init_function =
4525 "*init_function", /* name */
4527 init_function_for_compilation, /* execute */
4530 0, /* static_pass_number */
4531 TV_NONE, /* tv_id */
4532 0, /* properties_required */
4533 0, /* properties_provided */
4534 0, /* properties_destroyed */
4535 0, /* todo_flags_start */
4536 0 /* todo_flags_finish */
4542 expand_main_function (void)
4544 #if (defined(INVOKE__main) \
4545 || (!defined(HAS_INIT_SECTION) \
4546 && !defined(INIT_SECTION_ASM_OP) \
4547 && !defined(INIT_ARRAY_SECTION_ASM_OP)))
4548 emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0);
4552 /* Expand code to initialize the stack_protect_guard. This is invoked at
4553 the beginning of a function to be protected. */
4555 #ifndef HAVE_stack_protect_set
4556 # define HAVE_stack_protect_set 0
4557 # define gen_stack_protect_set(x,y) (gcc_unreachable (), NULL_RTX)
4561 stack_protect_prologue (void)
4563 tree guard_decl = targetm.stack_protect_guard ();
4566 x = expand_normal (crtl->stack_protect_guard);
4567 y = expand_normal (guard_decl);
4569 /* Allow the target to copy from Y to X without leaking Y into a
4571 if (HAVE_stack_protect_set)
4573 rtx insn = gen_stack_protect_set (x, y);
4581 /* Otherwise do a straight move. */
4582 emit_move_insn (x, y);
4585 /* Expand code to verify the stack_protect_guard. This is invoked at
4586 the end of a function to be protected. */
4588 #ifndef HAVE_stack_protect_test
4589 # define HAVE_stack_protect_test 0
4590 # define gen_stack_protect_test(x, y, z) (gcc_unreachable (), NULL_RTX)
4594 stack_protect_epilogue (void)
4596 tree guard_decl = targetm.stack_protect_guard ();
4597 rtx label = gen_label_rtx ();
4600 x = expand_normal (crtl->stack_protect_guard);
4601 y = expand_normal (guard_decl);
4603 /* Allow the target to compare Y with X without leaking either into
4605 switch (HAVE_stack_protect_test != 0)
4608 tmp = gen_stack_protect_test (x, y, label);
4617 emit_cmp_and_jump_insns (x, y, EQ, NULL_RTX, ptr_mode, 1, label);
4621 /* The noreturn predictor has been moved to the tree level. The rtl-level
4622 predictors estimate this branch about 20%, which isn't enough to get
4623 things moved out of line. Since this is the only extant case of adding
4624 a noreturn function at the rtl level, it doesn't seem worth doing ought
4625 except adding the prediction by hand. */
4626 tmp = get_last_insn ();
4628 predict_insn_def (tmp, PRED_NORETURN, TAKEN);
4630 expand_expr_stmt (targetm.stack_protect_fail ());
4634 /* Start the RTL for a new function, and set variables used for
4636 SUBR is the FUNCTION_DECL node.
4637 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4638 the function's parameters, which must be run at any return statement. */
4641 expand_function_start (tree subr)
4643 /* Make sure volatile mem refs aren't considered
4644 valid operands of arithmetic insns. */
4645 init_recog_no_volatile ();
4649 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
4652 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
4654 /* Make the label for return statements to jump to. Do not special
4655 case machines with special return instructions -- they will be
4656 handled later during jump, ifcvt, or epilogue creation. */
4657 return_label = gen_label_rtx ();
4659 /* Initialize rtx used to return the value. */
4660 /* Do this before assign_parms so that we copy the struct value address
4661 before any library calls that assign parms might generate. */
4663 /* Decide whether to return the value in memory or in a register. */
4664 if (aggregate_value_p (DECL_RESULT (subr), subr))
4666 /* Returning something that won't go in a register. */
4667 rtx value_address = 0;
4669 #ifdef PCC_STATIC_STRUCT_RETURN
4670 if (cfun->returns_pcc_struct)
4672 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
4673 value_address = assemble_static_space (size);
4678 rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 2);
4679 /* Expect to be passed the address of a place to store the value.
4680 If it is passed as an argument, assign_parms will take care of
4684 value_address = gen_reg_rtx (Pmode);
4685 emit_move_insn (value_address, sv);
4690 rtx x = value_address;
4691 if (!DECL_BY_REFERENCE (DECL_RESULT (subr)))
4693 x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), x);
4694 set_mem_attributes (x, DECL_RESULT (subr), 1);
4696 SET_DECL_RTL (DECL_RESULT (subr), x);
4699 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
4700 /* If return mode is void, this decl rtl should not be used. */
4701 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
4704 /* Compute the return values into a pseudo reg, which we will copy
4705 into the true return register after the cleanups are done. */
4706 tree return_type = TREE_TYPE (DECL_RESULT (subr));
4707 if (TYPE_MODE (return_type) != BLKmode
4708 && targetm.calls.return_in_msb (return_type))
4709 /* expand_function_end will insert the appropriate padding in
4710 this case. Use the return value's natural (unpadded) mode
4711 within the function proper. */
4712 SET_DECL_RTL (DECL_RESULT (subr),
4713 gen_reg_rtx (TYPE_MODE (return_type)));
4716 /* In order to figure out what mode to use for the pseudo, we
4717 figure out what the mode of the eventual return register will
4718 actually be, and use that. */
4719 rtx hard_reg = hard_function_value (return_type, subr, 0, 1);
4721 /* Structures that are returned in registers are not
4722 aggregate_value_p, so we may see a PARALLEL or a REG. */
4723 if (REG_P (hard_reg))
4724 SET_DECL_RTL (DECL_RESULT (subr),
4725 gen_reg_rtx (GET_MODE (hard_reg)));
4728 gcc_assert (GET_CODE (hard_reg) == PARALLEL);
4729 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
4733 /* Set DECL_REGISTER flag so that expand_function_end will copy the
4734 result to the real return register(s). */
4735 DECL_REGISTER (DECL_RESULT (subr)) = 1;
4738 /* Initialize rtx for parameters and local variables.
4739 In some cases this requires emitting insns. */
4740 assign_parms (subr);
4742 /* If function gets a static chain arg, store it. */
4743 if (cfun->static_chain_decl)
4745 tree parm = cfun->static_chain_decl;
4746 rtx local, chain, insn;
4748 local = gen_reg_rtx (Pmode);
4749 chain = targetm.calls.static_chain (current_function_decl, true);
4751 set_decl_incoming_rtl (parm, chain, false);
4752 SET_DECL_RTL (parm, local);
4753 mark_reg_pointer (local, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
4755 insn = emit_move_insn (local, chain);
4757 /* Mark the register as eliminable, similar to parameters. */
4759 && reg_mentioned_p (arg_pointer_rtx, XEXP (chain, 0)))
4760 set_unique_reg_note (insn, REG_EQUIV, chain);
4763 /* If the function receives a non-local goto, then store the
4764 bits we need to restore the frame pointer. */
4765 if (cfun->nonlocal_goto_save_area)
4770 /* ??? We need to do this save early. Unfortunately here is
4771 before the frame variable gets declared. Help out... */
4772 tree var = TREE_OPERAND (cfun->nonlocal_goto_save_area, 0);
4773 if (!DECL_RTL_SET_P (var))
4776 t_save = build4 (ARRAY_REF,
4777 TREE_TYPE (TREE_TYPE (cfun->nonlocal_goto_save_area)),
4778 cfun->nonlocal_goto_save_area,
4779 integer_zero_node, NULL_TREE, NULL_TREE);
4780 r_save = expand_expr (t_save, NULL_RTX, VOIDmode, EXPAND_WRITE);
4781 gcc_assert (GET_MODE (r_save) == Pmode);
4783 emit_move_insn (r_save, targetm.builtin_setjmp_frame_value ());
4784 update_nonlocal_goto_save_area ();
4787 /* The following was moved from init_function_start.
4788 The move is supposed to make sdb output more accurate. */
4789 /* Indicate the beginning of the function body,
4790 as opposed to parm setup. */
4791 emit_note (NOTE_INSN_FUNCTION_BEG);
4793 gcc_assert (NOTE_P (get_last_insn ()));
4795 parm_birth_insn = get_last_insn ();
4800 PROFILE_HOOK (current_function_funcdef_no);
4804 /* If we are doing generic stack checking, the probe should go here. */
4805 if (flag_stack_check == GENERIC_STACK_CHECK)
4806 stack_check_probe_note = emit_note (NOTE_INSN_DELETED);
4808 /* Make sure there is a line number after the function entry setup code. */
4809 force_next_line_note ();
4812 /* Undo the effects of init_dummy_function_start. */
4814 expand_dummy_function_end (void)
4816 gcc_assert (in_dummy_function);
4818 /* End any sequences that failed to be closed due to syntax errors. */
4819 while (in_sequence_p ())
4822 /* Outside function body, can't compute type's actual size
4823 until next function's body starts. */
4825 free_after_parsing (cfun);
4826 free_after_compilation (cfun);
4828 in_dummy_function = false;
4831 /* Call DOIT for each hard register used as a return value from
4832 the current function. */
4835 diddle_return_value (void (*doit) (rtx, void *), void *arg)
4837 rtx outgoing = crtl->return_rtx;
4842 if (REG_P (outgoing))
4843 (*doit) (outgoing, arg);
4844 else if (GET_CODE (outgoing) == PARALLEL)
4848 for (i = 0; i < XVECLEN (outgoing, 0); i++)
4850 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
4852 if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER)
4859 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
4865 clobber_return_register (void)
4867 diddle_return_value (do_clobber_return_reg, NULL);
4869 /* In case we do use pseudo to return value, clobber it too. */
4870 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
4872 tree decl_result = DECL_RESULT (current_function_decl);
4873 rtx decl_rtl = DECL_RTL (decl_result);
4874 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
4876 do_clobber_return_reg (decl_rtl, NULL);
4882 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
4888 use_return_register (void)
4890 diddle_return_value (do_use_return_reg, NULL);
4893 /* Possibly warn about unused parameters. */
4895 do_warn_unused_parameter (tree fn)
4899 for (decl = DECL_ARGUMENTS (fn);
4900 decl; decl = DECL_CHAIN (decl))
4901 if (!TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
4902 && DECL_NAME (decl) && !DECL_ARTIFICIAL (decl)
4903 && !TREE_NO_WARNING (decl))
4904 warning (OPT_Wunused_parameter, "unused parameter %q+D", decl);
4907 static GTY(()) rtx initial_trampoline;
4909 /* Generate RTL for the end of the current function. */
4912 expand_function_end (void)
4916 /* If arg_pointer_save_area was referenced only from a nested
4917 function, we will not have initialized it yet. Do that now. */
4918 if (arg_pointer_save_area && ! crtl->arg_pointer_save_area_init)
4919 get_arg_pointer_save_area ();
4921 /* If we are doing generic stack checking and this function makes calls,
4922 do a stack probe at the start of the function to ensure we have enough
4923 space for another stack frame. */
4924 if (flag_stack_check == GENERIC_STACK_CHECK)
4928 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4931 rtx max_frame_size = GEN_INT (STACK_CHECK_MAX_FRAME_SIZE);
4933 if (STACK_CHECK_MOVING_SP)
4934 anti_adjust_stack_and_probe (max_frame_size, true);
4936 probe_stack_range (STACK_OLD_CHECK_PROTECT, max_frame_size);
4939 set_insn_locators (seq, prologue_locator);
4940 emit_insn_before (seq, stack_check_probe_note);
4945 /* End any sequences that failed to be closed due to syntax errors. */
4946 while (in_sequence_p ())
4949 clear_pending_stack_adjust ();
4950 do_pending_stack_adjust ();
4952 /* Output a linenumber for the end of the function.
4953 SDB depends on this. */
4954 force_next_line_note ();
4955 set_curr_insn_source_location (input_location);
4957 /* Before the return label (if any), clobber the return
4958 registers so that they are not propagated live to the rest of
4959 the function. This can only happen with functions that drop
4960 through; if there had been a return statement, there would
4961 have either been a return rtx, or a jump to the return label.
4963 We delay actual code generation after the current_function_value_rtx
4965 clobber_after = get_last_insn ();
4967 /* Output the label for the actual return from the function. */
4968 emit_label (return_label);
4970 if (targetm_common.except_unwind_info (&global_options) == UI_SJLJ)
4972 /* Let except.c know where it should emit the call to unregister
4973 the function context for sjlj exceptions. */
4974 if (flag_exceptions)
4975 sjlj_emit_function_exit_after (get_last_insn ());
4979 /* We want to ensure that instructions that may trap are not
4980 moved into the epilogue by scheduling, because we don't
4981 always emit unwind information for the epilogue. */
4982 if (cfun->can_throw_non_call_exceptions)
4983 emit_insn (gen_blockage ());
4986 /* If this is an implementation of throw, do what's necessary to
4987 communicate between __builtin_eh_return and the epilogue. */
4988 expand_eh_return ();
4990 /* If scalar return value was computed in a pseudo-reg, or was a named
4991 return value that got dumped to the stack, copy that to the hard
4993 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
4995 tree decl_result = DECL_RESULT (current_function_decl);
4996 rtx decl_rtl = DECL_RTL (decl_result);
4998 if (REG_P (decl_rtl)
4999 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5000 : DECL_REGISTER (decl_result))
5002 rtx real_decl_rtl = crtl->return_rtx;
5004 /* This should be set in assign_parms. */
5005 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl));
5007 /* If this is a BLKmode structure being returned in registers,
5008 then use the mode computed in expand_return. Note that if
5009 decl_rtl is memory, then its mode may have been changed,
5010 but that crtl->return_rtx has not. */
5011 if (GET_MODE (real_decl_rtl) == BLKmode)
5012 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
5014 /* If a non-BLKmode return value should be padded at the least
5015 significant end of the register, shift it left by the appropriate
5016 amount. BLKmode results are handled using the group load/store
5018 if (TYPE_MODE (TREE_TYPE (decl_result)) != BLKmode
5019 && targetm.calls.return_in_msb (TREE_TYPE (decl_result)))
5021 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl),
5022 REGNO (real_decl_rtl)),
5024 shift_return_value (GET_MODE (decl_rtl), true, real_decl_rtl);
5026 /* If a named return value dumped decl_return to memory, then
5027 we may need to re-do the PROMOTE_MODE signed/unsigned
5029 else if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
5031 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (decl_result));
5032 promote_function_mode (TREE_TYPE (decl_result),
5033 GET_MODE (decl_rtl), &unsignedp,
5034 TREE_TYPE (current_function_decl), 1);
5036 convert_move (real_decl_rtl, decl_rtl, unsignedp);
5038 else if (GET_CODE (real_decl_rtl) == PARALLEL)
5040 /* If expand_function_start has created a PARALLEL for decl_rtl,
5041 move the result to the real return registers. Otherwise, do
5042 a group load from decl_rtl for a named return. */
5043 if (GET_CODE (decl_rtl) == PARALLEL)
5044 emit_group_move (real_decl_rtl, decl_rtl);
5046 emit_group_load (real_decl_rtl, decl_rtl,
5047 TREE_TYPE (decl_result),
5048 int_size_in_bytes (TREE_TYPE (decl_result)));
5050 /* In the case of complex integer modes smaller than a word, we'll
5051 need to generate some non-trivial bitfield insertions. Do that
5052 on a pseudo and not the hard register. */
5053 else if (GET_CODE (decl_rtl) == CONCAT
5054 && GET_MODE_CLASS (GET_MODE (decl_rtl)) == MODE_COMPLEX_INT
5055 && GET_MODE_BITSIZE (GET_MODE (decl_rtl)) <= BITS_PER_WORD)
5057 int old_generating_concat_p;
5060 old_generating_concat_p = generating_concat_p;
5061 generating_concat_p = 0;
5062 tmp = gen_reg_rtx (GET_MODE (decl_rtl));
5063 generating_concat_p = old_generating_concat_p;
5065 emit_move_insn (tmp, decl_rtl);
5066 emit_move_insn (real_decl_rtl, tmp);
5069 emit_move_insn (real_decl_rtl, decl_rtl);
5073 /* If returning a structure, arrange to return the address of the value
5074 in a place where debuggers expect to find it.
5076 If returning a structure PCC style,
5077 the caller also depends on this value.
5078 And cfun->returns_pcc_struct is not necessarily set. */
5079 if (cfun->returns_struct
5080 || cfun->returns_pcc_struct)
5082 rtx value_address = DECL_RTL (DECL_RESULT (current_function_decl));
5083 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
5086 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))
5087 type = TREE_TYPE (type);
5089 value_address = XEXP (value_address, 0);
5091 outgoing = targetm.calls.function_value (build_pointer_type (type),
5092 current_function_decl, true);
5094 /* Mark this as a function return value so integrate will delete the
5095 assignment and USE below when inlining this function. */
5096 REG_FUNCTION_VALUE_P (outgoing) = 1;
5098 /* The address may be ptr_mode and OUTGOING may be Pmode. */
5099 value_address = convert_memory_address (GET_MODE (outgoing),
5102 emit_move_insn (outgoing, value_address);
5104 /* Show return register used to hold result (in this case the address
5106 crtl->return_rtx = outgoing;
5109 /* Emit the actual code to clobber return register. */
5114 clobber_return_register ();
5118 emit_insn_after (seq, clobber_after);
5121 /* Output the label for the naked return from the function. */
5122 if (naked_return_label)
5123 emit_label (naked_return_label);
5125 /* @@@ This is a kludge. We want to ensure that instructions that
5126 may trap are not moved into the epilogue by scheduling, because
5127 we don't always emit unwind information for the epilogue. */
5128 if (cfun->can_throw_non_call_exceptions
5129 && targetm_common.except_unwind_info (&global_options) != UI_SJLJ)
5130 emit_insn (gen_blockage ());
5132 /* If stack protection is enabled for this function, check the guard. */
5133 if (crtl->stack_protect_guard)
5134 stack_protect_epilogue ();
5136 /* If we had calls to alloca, and this machine needs
5137 an accurate stack pointer to exit the function,
5138 insert some code to save and restore the stack pointer. */
5139 if (! EXIT_IGNORE_STACK
5140 && cfun->calls_alloca)
5145 emit_stack_save (SAVE_FUNCTION, &tem);
5148 emit_insn_before (seq, parm_birth_insn);
5150 emit_stack_restore (SAVE_FUNCTION, tem);
5153 /* ??? This should no longer be necessary since stupid is no longer with
5154 us, but there are some parts of the compiler (eg reload_combine, and
5155 sh mach_dep_reorg) that still try and compute their own lifetime info
5156 instead of using the general framework. */
5157 use_return_register ();
5161 get_arg_pointer_save_area (void)
5163 rtx ret = arg_pointer_save_area;
5167 ret = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
5168 arg_pointer_save_area = ret;
5171 if (! crtl->arg_pointer_save_area_init)
5175 /* Save the arg pointer at the beginning of the function. The
5176 generated stack slot may not be a valid memory address, so we
5177 have to check it and fix it if necessary. */
5179 emit_move_insn (validize_mem (ret),
5180 crtl->args.internal_arg_pointer);
5184 push_topmost_sequence ();
5185 emit_insn_after (seq, entry_of_function ());
5186 pop_topmost_sequence ();
5188 crtl->arg_pointer_save_area_init = true;
5194 /* Add a list of INSNS to the hash HASHP, possibly allocating HASHP
5195 for the first time. */
5198 record_insns (rtx insns, rtx end, htab_t *hashp)
5201 htab_t hash = *hashp;
5205 = htab_create_ggc (17, htab_hash_pointer, htab_eq_pointer, NULL);
5207 for (tmp = insns; tmp != end; tmp = NEXT_INSN (tmp))
5209 void **slot = htab_find_slot (hash, tmp, INSERT);
5210 gcc_assert (*slot == NULL);
5215 /* INSN has been duplicated or replaced by as COPY, perhaps by duplicating a
5216 basic block, splitting or peepholes. If INSN is a prologue or epilogue
5217 insn, then record COPY as well. */
5220 maybe_copy_prologue_epilogue_insn (rtx insn, rtx copy)
5225 hash = epilogue_insn_hash;
5226 if (!hash || !htab_find (hash, insn))
5228 hash = prologue_insn_hash;
5229 if (!hash || !htab_find (hash, insn))
5233 slot = htab_find_slot (hash, copy, INSERT);
5234 gcc_assert (*slot == NULL);
5238 /* Set the locator of the insn chain starting at INSN to LOC. */
5240 set_insn_locators (rtx insn, int loc)
5242 while (insn != NULL_RTX)
5245 INSN_LOCATOR (insn) = loc;
5246 insn = NEXT_INSN (insn);
5250 /* Determine if any INSNs in HASH are, or are part of, INSN. Because
5251 we can be running after reorg, SEQUENCE rtl is possible. */
5254 contains (const_rtx insn, htab_t hash)
5259 if (NONJUMP_INSN_P (insn) && GET_CODE (PATTERN (insn)) == SEQUENCE)
5262 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
5263 if (htab_find (hash, XVECEXP (PATTERN (insn), 0, i)))
5268 return htab_find (hash, insn) != NULL;
5272 prologue_epilogue_contains (const_rtx insn)
5274 if (contains (insn, prologue_insn_hash))
5276 if (contains (insn, epilogue_insn_hash))
5281 #ifdef HAVE_simple_return
5283 /* Return true if INSN requires the stack frame to be set up.
5284 PROLOGUE_USED contains the hard registers used in the function
5285 prologue. SET_UP_BY_PROLOGUE is the set of registers we expect the
5286 prologue to set up for the function. */
5288 requires_stack_frame_p (rtx insn, HARD_REG_SET prologue_used,
5289 HARD_REG_SET set_up_by_prologue)
5292 HARD_REG_SET hardregs;
5296 return !SIBLING_CALL_P (insn);
5298 CLEAR_HARD_REG_SET (hardregs);
5299 for (df_rec = DF_INSN_DEFS (insn); *df_rec; df_rec++)
5301 rtx dreg = DF_REF_REG (*df_rec);
5306 add_to_hard_reg_set (&hardregs, GET_MODE (dreg),
5309 if (hard_reg_set_intersect_p (hardregs, prologue_used))
5311 AND_COMPL_HARD_REG_SET (hardregs, call_used_reg_set);
5312 for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
5313 if (TEST_HARD_REG_BIT (hardregs, regno)
5314 && df_regs_ever_live_p (regno))
5317 for (df_rec = DF_INSN_USES (insn); *df_rec; df_rec++)
5319 rtx reg = DF_REF_REG (*df_rec);
5324 add_to_hard_reg_set (&hardregs, GET_MODE (reg),
5327 if (hard_reg_set_intersect_p (hardregs, set_up_by_prologue))
5333 /* Look for sets of call-saved registers in the first block of the
5334 function, and move them down into successor blocks if the register
5335 is used only on one path. This exposes more opportunities for
5337 These kinds of sets often occur when incoming argument registers are
5338 moved to call-saved registers because their values are live across
5339 one or more calls during the function. */
5342 prepare_shrink_wrap (basic_block entry_block)
5345 FOR_BB_INSNS_SAFE (entry_block, insn, curr)
5347 basic_block next_bb;
5351 unsigned destreg, srcreg;
5353 if (!NONDEBUG_INSN_P (insn))
5355 set = single_set (insn);
5359 if (!REG_P (SET_SRC (set)) || !REG_P (SET_DEST (set)))
5361 srcreg = REGNO (SET_SRC (set));
5362 destreg = REGNO (SET_DEST (set));
5363 if (hard_regno_nregs[srcreg][GET_MODE (SET_SRC (set))] > 1
5364 || hard_regno_nregs[destreg][GET_MODE (SET_DEST (set))] > 1)
5367 next_bb = entry_block;
5373 /* Try to find a single edge across which the register is live.
5374 If we find one, we'll try to move the set across this edge. */
5375 FOR_EACH_EDGE (e, ei, next_bb->succs)
5377 if (REGNO_REG_SET_P (df_get_live_in (e->dest), destreg))
5389 /* We can sometimes encounter dead code. Don't try to move it
5390 into the exit block. */
5391 if (live_edge->dest == EXIT_BLOCK_PTR)
5393 if (EDGE_COUNT (live_edge->dest->preds) > 1)
5395 while (scan != BB_END (next_bb))
5397 scan = NEXT_INSN (scan);
5398 if (NONDEBUG_INSN_P (scan))
5401 HARD_REG_SET set_regs;
5403 CLEAR_HARD_REG_SET (set_regs);
5404 note_stores (PATTERN (scan), record_hard_reg_sets,
5407 IOR_HARD_REG_SET (set_regs, call_used_reg_set);
5408 for (link = REG_NOTES (scan); link; link = XEXP (link, 1))
5409 if (REG_NOTE_KIND (link) == REG_INC)
5410 record_hard_reg_sets (XEXP (link, 0), NULL, &set_regs);
5412 if (TEST_HARD_REG_BIT (set_regs, srcreg)
5413 || reg_referenced_p (SET_DEST (set),
5421 rtx link = CALL_INSN_FUNCTION_USAGE (scan);
5424 rtx tmp = XEXP (link, 0);
5425 if (GET_CODE (tmp) == USE
5426 && reg_referenced_p (SET_DEST (set), tmp))
5428 link = XEXP (link, 1);
5440 next_bb = live_edge->dest;
5443 if (next_bb != entry_block)
5445 rtx after = BB_HEAD (next_bb);
5446 while (!NOTE_P (after)
5447 || NOTE_KIND (after) != NOTE_INSN_BASIC_BLOCK)
5448 after = NEXT_INSN (after);
5449 emit_insn_after (PATTERN (insn), after);
5458 /* Insert use of return register before the end of BB. */
5461 emit_use_return_register_into_block (basic_block bb)
5465 use_return_register ();
5468 emit_insn_before (seq, BB_END (bb));
5472 /* Create a return pattern, either simple_return or return, depending on
5476 gen_return_pattern (bool simple_p)
5478 #ifdef HAVE_simple_return
5479 return simple_p ? gen_simple_return () : gen_return ();
5481 gcc_assert (!simple_p);
5482 return gen_return ();
5486 /* Insert an appropriate return pattern at the end of block BB. This
5487 also means updating block_for_insn appropriately. SIMPLE_P is
5488 the same as in gen_return_pattern and passed to it. */
5491 emit_return_into_block (bool simple_p, basic_block bb)
5494 jump = emit_jump_insn_after (gen_return_pattern (simple_p), BB_END (bb));
5495 pat = PATTERN (jump);
5496 if (GET_CODE (pat) == PARALLEL)
5497 pat = XVECEXP (pat, 0, 0);
5498 gcc_assert (ANY_RETURN_P (pat));
5499 JUMP_LABEL (jump) = pat;
5503 /* Set JUMP_LABEL for a return insn. */
5506 set_return_jump_label (rtx returnjump)
5508 rtx pat = PATTERN (returnjump);
5509 if (GET_CODE (pat) == PARALLEL)
5510 pat = XVECEXP (pat, 0, 0);
5511 if (ANY_RETURN_P (pat))
5512 JUMP_LABEL (returnjump) = pat;
5514 JUMP_LABEL (returnjump) = ret_rtx;
5517 #ifdef HAVE_simple_return
5518 /* Create a copy of BB instructions and insert at BEFORE. Redirect
5519 preds of BB to COPY_BB if they don't appear in NEED_PROLOGUE. */
5521 dup_block_and_redirect (basic_block bb, basic_block copy_bb, rtx before,
5522 bitmap_head *need_prologue)
5526 rtx insn = BB_END (bb);
5528 /* We know BB has a single successor, so there is no need to copy a
5529 simple jump at the end of BB. */
5530 if (simplejump_p (insn))
5531 insn = PREV_INSN (insn);
5534 duplicate_insn_chain (BB_HEAD (bb), insn);
5538 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
5539 if (active_insn_p (insn))
5541 fprintf (dump_file, "Duplicating bb %d to bb %d, %u active insns.\n",
5542 bb->index, copy_bb->index, count);
5544 insn = get_insns ();
5546 emit_insn_before (insn, before);
5548 /* Redirect all the paths that need no prologue into copy_bb. */
5549 for (ei = ei_start (bb->preds); (e = ei_safe_edge (ei)); )
5550 if (!bitmap_bit_p (need_prologue, e->src->index))
5552 redirect_edge_and_branch_force (e, copy_bb);
5560 #if defined (HAVE_return) || defined (HAVE_simple_return)
5561 /* Return true if there are any active insns between HEAD and TAIL. */
5563 active_insn_between (rtx head, rtx tail)
5567 if (active_insn_p (tail))
5571 tail = PREV_INSN (tail);
5576 /* LAST_BB is a block that exits, and empty of active instructions.
5577 Examine its predecessors for jumps that can be converted to
5578 (conditional) returns. */
5579 static VEC (edge, heap) *
5580 convert_jumps_to_returns (basic_block last_bb, bool simple_p,
5581 VEC (edge, heap) *unconverted ATTRIBUTE_UNUSED)
5588 VEC(basic_block,heap) *src_bbs;
5590 src_bbs = VEC_alloc (basic_block, heap, EDGE_COUNT (last_bb->preds));
5591 FOR_EACH_EDGE (e, ei, last_bb->preds)
5592 if (e->src != ENTRY_BLOCK_PTR)
5593 VEC_quick_push (basic_block, src_bbs, e->src);
5595 label = BB_HEAD (last_bb);
5597 FOR_EACH_VEC_ELT (basic_block, src_bbs, i, bb)
5599 rtx jump = BB_END (bb);
5601 if (!JUMP_P (jump) || JUMP_LABEL (jump) != label)
5604 e = find_edge (bb, last_bb);
5606 /* If we have an unconditional jump, we can replace that
5607 with a simple return instruction. */
5608 if (simplejump_p (jump))
5610 /* The use of the return register might be present in the exit
5611 fallthru block. Either:
5612 - removing the use is safe, and we should remove the use in
5613 the exit fallthru block, or
5614 - removing the use is not safe, and we should add it here.
5615 For now, we conservatively choose the latter. Either of the
5616 2 helps in crossjumping. */
5617 emit_use_return_register_into_block (bb);
5619 emit_return_into_block (simple_p, bb);
5623 /* If we have a conditional jump branching to the last
5624 block, we can try to replace that with a conditional
5625 return instruction. */
5626 else if (condjump_p (jump))
5631 dest = simple_return_rtx;
5634 if (!redirect_jump (jump, dest, 0))
5636 #ifdef HAVE_simple_return
5641 "Failed to redirect bb %d branch.\n", bb->index);
5642 VEC_safe_push (edge, heap, unconverted, e);
5648 /* See comment in simplejump_p case above. */
5649 emit_use_return_register_into_block (bb);
5651 /* If this block has only one successor, it both jumps
5652 and falls through to the fallthru block, so we can't
5654 if (single_succ_p (bb))
5659 #ifdef HAVE_simple_return
5664 "Failed to redirect bb %d branch.\n", bb->index);
5665 VEC_safe_push (edge, heap, unconverted, e);
5671 /* Fix up the CFG for the successful change we just made. */
5672 redirect_edge_succ (e, EXIT_BLOCK_PTR);
5674 VEC_free (basic_block, heap, src_bbs);
5678 /* Emit a return insn for the exit fallthru block. */
5680 emit_return_for_exit (edge exit_fallthru_edge, bool simple_p)
5682 basic_block last_bb = exit_fallthru_edge->src;
5684 if (JUMP_P (BB_END (last_bb)))
5686 last_bb = split_edge (exit_fallthru_edge);
5687 exit_fallthru_edge = single_succ_edge (last_bb);
5689 emit_barrier_after (BB_END (last_bb));
5690 emit_return_into_block (simple_p, last_bb);
5691 exit_fallthru_edge->flags &= ~EDGE_FALLTHRU;
5697 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
5698 this into place with notes indicating where the prologue ends and where
5699 the epilogue begins. Update the basic block information when possible.
5701 Notes on epilogue placement:
5702 There are several kinds of edges to the exit block:
5703 * a single fallthru edge from LAST_BB
5704 * possibly, edges from blocks containing sibcalls
5705 * possibly, fake edges from infinite loops
5707 The epilogue is always emitted on the fallthru edge from the last basic
5708 block in the function, LAST_BB, into the exit block.
5710 If LAST_BB is empty except for a label, it is the target of every
5711 other basic block in the function that ends in a return. If a
5712 target has a return or simple_return pattern (possibly with
5713 conditional variants), these basic blocks can be changed so that a
5714 return insn is emitted into them, and their target is adjusted to
5715 the real exit block.
5717 Notes on shrink wrapping: We implement a fairly conservative
5718 version of shrink-wrapping rather than the textbook one. We only
5719 generate a single prologue and a single epilogue. This is
5720 sufficient to catch a number of interesting cases involving early
5723 First, we identify the blocks that require the prologue to occur before
5724 them. These are the ones that modify a call-saved register, or reference
5725 any of the stack or frame pointer registers. To simplify things, we then
5726 mark everything reachable from these blocks as also requiring a prologue.
5727 This takes care of loops automatically, and avoids the need to examine
5728 whether MEMs reference the frame, since it is sufficient to check for
5729 occurrences of the stack or frame pointer.
5731 We then compute the set of blocks for which the need for a prologue
5732 is anticipatable (borrowing terminology from the shrink-wrapping
5733 description in Muchnick's book). These are the blocks which either
5734 require a prologue themselves, or those that have only successors
5735 where the prologue is anticipatable. The prologue needs to be
5736 inserted on all edges from BB1->BB2 where BB2 is in ANTIC and BB1
5737 is not. For the moment, we ensure that only one such edge exists.
5739 The epilogue is placed as described above, but we make a
5740 distinction between inserting return and simple_return patterns
5741 when modifying other blocks that end in a return. Blocks that end
5742 in a sibcall omit the sibcall_epilogue if the block is not in
5746 thread_prologue_and_epilogue_insns (void)
5749 #ifdef HAVE_simple_return
5750 VEC (edge, heap) *unconverted_simple_returns = NULL;
5751 bool nonempty_prologue;
5752 bitmap_head bb_flags;
5753 unsigned max_grow_size;
5756 rtx seq ATTRIBUTE_UNUSED, epilogue_end ATTRIBUTE_UNUSED;
5757 rtx prologue_seq ATTRIBUTE_UNUSED, split_prologue_seq ATTRIBUTE_UNUSED;
5758 edge e, entry_edge, orig_entry_edge, exit_fallthru_edge;
5763 rtl_profile_for_bb (ENTRY_BLOCK_PTR);
5767 epilogue_end = NULL_RTX;
5768 returnjump = NULL_RTX;
5770 /* Can't deal with multiple successors of the entry block at the
5771 moment. Function should always have at least one entry
5773 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR));
5774 entry_edge = single_succ_edge (ENTRY_BLOCK_PTR);
5775 orig_entry_edge = entry_edge;
5777 split_prologue_seq = NULL_RTX;
5778 if (flag_split_stack
5779 && (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (cfun->decl))
5782 #ifndef HAVE_split_stack_prologue
5785 gcc_assert (HAVE_split_stack_prologue);
5788 emit_insn (gen_split_stack_prologue ());
5789 split_prologue_seq = get_insns ();
5792 record_insns (split_prologue_seq, NULL, &prologue_insn_hash);
5793 set_insn_locators (split_prologue_seq, prologue_locator);
5797 prologue_seq = NULL_RTX;
5798 #ifdef HAVE_prologue
5802 seq = gen_prologue ();
5805 /* Insert an explicit USE for the frame pointer
5806 if the profiling is on and the frame pointer is required. */
5807 if (crtl->profile && frame_pointer_needed)
5808 emit_use (hard_frame_pointer_rtx);
5810 /* Retain a map of the prologue insns. */
5811 record_insns (seq, NULL, &prologue_insn_hash);
5812 emit_note (NOTE_INSN_PROLOGUE_END);
5814 /* Ensure that instructions are not moved into the prologue when
5815 profiling is on. The call to the profiling routine can be
5816 emitted within the live range of a call-clobbered register. */
5817 if (!targetm.profile_before_prologue () && crtl->profile)
5818 emit_insn (gen_blockage ());
5820 prologue_seq = get_insns ();
5822 set_insn_locators (prologue_seq, prologue_locator);
5826 #ifdef HAVE_simple_return
5827 bitmap_initialize (&bb_flags, &bitmap_default_obstack);
5829 /* Try to perform a kind of shrink-wrapping, making sure the
5830 prologue/epilogue is emitted only around those parts of the
5831 function that require it. */
5833 nonempty_prologue = false;
5834 for (seq = prologue_seq; seq; seq = NEXT_INSN (seq))
5835 if (!NOTE_P (seq) || NOTE_KIND (seq) != NOTE_INSN_PROLOGUE_END)
5837 nonempty_prologue = true;
5841 if (flag_shrink_wrap && HAVE_simple_return
5842 && (targetm.profile_before_prologue () || !crtl->profile)
5843 && nonempty_prologue && !crtl->calls_eh_return)
5845 HARD_REG_SET prologue_clobbered, prologue_used, live_on_edge;
5846 HARD_REG_SET set_up_by_prologue;
5848 VEC(basic_block, heap) *vec;
5850 bitmap_head bb_antic_flags;
5851 bitmap_head bb_on_list;
5852 bitmap_head bb_tail;
5855 fprintf (dump_file, "Attempting shrink-wrapping optimization.\n");
5857 /* Compute the registers set and used in the prologue. */
5858 CLEAR_HARD_REG_SET (prologue_clobbered);
5859 CLEAR_HARD_REG_SET (prologue_used);
5860 for (p_insn = prologue_seq; p_insn; p_insn = NEXT_INSN (p_insn))
5862 HARD_REG_SET this_used;
5863 if (!NONDEBUG_INSN_P (p_insn))
5866 CLEAR_HARD_REG_SET (this_used);
5867 note_uses (&PATTERN (p_insn), record_hard_reg_uses,
5869 AND_COMPL_HARD_REG_SET (this_used, prologue_clobbered);
5870 IOR_HARD_REG_SET (prologue_used, this_used);
5871 note_stores (PATTERN (p_insn), record_hard_reg_sets,
5872 &prologue_clobbered);
5875 prepare_shrink_wrap (entry_edge->dest);
5877 bitmap_initialize (&bb_antic_flags, &bitmap_default_obstack);
5878 bitmap_initialize (&bb_on_list, &bitmap_default_obstack);
5879 bitmap_initialize (&bb_tail, &bitmap_default_obstack);
5881 /* Find the set of basic blocks that require a stack frame,
5882 and blocks that are too big to be duplicated. */
5884 vec = VEC_alloc (basic_block, heap, n_basic_blocks);
5886 CLEAR_HARD_REG_SET (set_up_by_prologue);
5887 add_to_hard_reg_set (&set_up_by_prologue, Pmode, STACK_POINTER_REGNUM);
5888 add_to_hard_reg_set (&set_up_by_prologue, Pmode, ARG_POINTER_REGNUM);
5889 if (frame_pointer_needed)
5890 add_to_hard_reg_set (&set_up_by_prologue, Pmode,
5891 HARD_FRAME_POINTER_REGNUM);
5892 if (pic_offset_table_rtx)
5893 add_to_hard_reg_set (&set_up_by_prologue, Pmode,
5894 PIC_OFFSET_TABLE_REGNUM);
5896 /* We don't use a different max size depending on
5897 optimize_bb_for_speed_p because increasing shrink-wrapping
5898 opportunities by duplicating tail blocks can actually result
5899 in an overall decrease in code size. */
5900 max_grow_size = get_uncond_jump_length ();
5901 max_grow_size *= PARAM_VALUE (PARAM_MAX_GROW_COPY_BB_INSNS);
5908 FOR_BB_INSNS (bb, insn)
5909 if (NONDEBUG_INSN_P (insn))
5911 if (requires_stack_frame_p (insn, prologue_used,
5912 set_up_by_prologue))
5914 if (bb == entry_edge->dest)
5915 goto fail_shrinkwrap;
5916 bitmap_set_bit (&bb_flags, bb->index);
5917 VEC_quick_push (basic_block, vec, bb);
5920 else if (size <= max_grow_size)
5922 size += get_attr_min_length (insn);
5923 if (size > max_grow_size)
5924 bitmap_set_bit (&bb_on_list, bb->index);
5929 /* Blocks that really need a prologue, or are too big for tails. */
5930 bitmap_ior_into (&bb_on_list, &bb_flags);
5932 /* For every basic block that needs a prologue, mark all blocks
5933 reachable from it, so as to ensure they are also seen as
5934 requiring a prologue. */
5935 while (!VEC_empty (basic_block, vec))
5937 basic_block tmp_bb = VEC_pop (basic_block, vec);
5939 FOR_EACH_EDGE (e, ei, tmp_bb->succs)
5940 if (e->dest != EXIT_BLOCK_PTR
5941 && bitmap_set_bit (&bb_flags, e->dest->index))
5942 VEC_quick_push (basic_block, vec, e->dest);
5945 /* Find the set of basic blocks that need no prologue, have a
5946 single successor, can be duplicated, meet a max size
5947 requirement, and go to the exit via like blocks. */
5948 VEC_quick_push (basic_block, vec, EXIT_BLOCK_PTR);
5949 while (!VEC_empty (basic_block, vec))
5951 basic_block tmp_bb = VEC_pop (basic_block, vec);
5953 FOR_EACH_EDGE (e, ei, tmp_bb->preds)
5954 if (single_succ_p (e->src)
5955 && !bitmap_bit_p (&bb_on_list, e->src->index)
5956 && can_duplicate_block_p (e->src)
5957 && bitmap_set_bit (&bb_tail, e->src->index))
5958 VEC_quick_push (basic_block, vec, e->src);
5961 /* Now walk backwards from every block that is marked as needing
5962 a prologue to compute the bb_antic_flags bitmap. Exclude
5963 tail blocks; They can be duplicated to be used on paths not
5964 needing a prologue. */
5965 bitmap_clear (&bb_on_list);
5966 bitmap_and_compl (&bb_antic_flags, &bb_flags, &bb_tail);
5969 if (!bitmap_bit_p (&bb_antic_flags, bb->index))
5971 FOR_EACH_EDGE (e, ei, bb->preds)
5972 if (!bitmap_bit_p (&bb_antic_flags, e->src->index)
5973 && bitmap_set_bit (&bb_on_list, e->src->index))
5974 VEC_quick_push (basic_block, vec, e->src);
5976 while (!VEC_empty (basic_block, vec))
5978 basic_block tmp_bb = VEC_pop (basic_block, vec);
5979 bool all_set = true;
5981 bitmap_clear_bit (&bb_on_list, tmp_bb->index);
5982 FOR_EACH_EDGE (e, ei, tmp_bb->succs)
5983 if (!bitmap_bit_p (&bb_antic_flags, e->dest->index))
5991 bitmap_set_bit (&bb_antic_flags, tmp_bb->index);
5992 FOR_EACH_EDGE (e, ei, tmp_bb->preds)
5993 if (!bitmap_bit_p (&bb_antic_flags, e->src->index)
5994 && bitmap_set_bit (&bb_on_list, e->src->index))
5995 VEC_quick_push (basic_block, vec, e->src);
5998 /* Find exactly one edge that leads to a block in ANTIC from
5999 a block that isn't. */
6000 if (!bitmap_bit_p (&bb_antic_flags, entry_edge->dest->index))
6003 if (!bitmap_bit_p (&bb_antic_flags, bb->index))
6005 FOR_EACH_EDGE (e, ei, bb->preds)
6006 if (!bitmap_bit_p (&bb_antic_flags, e->src->index))
6008 if (entry_edge != orig_entry_edge)
6010 entry_edge = orig_entry_edge;
6012 fprintf (dump_file, "More than one candidate edge.\n");
6013 goto fail_shrinkwrap;
6016 fprintf (dump_file, "Found candidate edge for "
6017 "shrink-wrapping, %d->%d.\n", e->src->index,
6023 if (entry_edge != orig_entry_edge)
6025 /* Test whether the prologue is known to clobber any register
6026 (other than FP or SP) which are live on the edge. */
6027 CLEAR_HARD_REG_BIT (prologue_clobbered, STACK_POINTER_REGNUM);
6028 if (frame_pointer_needed)
6029 CLEAR_HARD_REG_BIT (prologue_clobbered, HARD_FRAME_POINTER_REGNUM);
6030 CLEAR_HARD_REG_SET (live_on_edge);
6031 reg_set_to_hard_reg_set (&live_on_edge,
6032 df_get_live_in (entry_edge->dest));
6033 if (hard_reg_set_intersect_p (live_on_edge, prologue_clobbered))
6035 entry_edge = orig_entry_edge;
6038 "Shrink-wrapping aborted due to clobber.\n");
6041 if (entry_edge != orig_entry_edge)
6043 crtl->shrink_wrapped = true;
6045 fprintf (dump_file, "Performing shrink-wrapping.\n");
6047 /* Find tail blocks reachable from both blocks needing a
6048 prologue and blocks not needing a prologue. */
6049 if (!bitmap_empty_p (&bb_tail))
6052 bool some_pro, some_no_pro;
6053 if (!bitmap_bit_p (&bb_tail, bb->index))
6055 some_pro = some_no_pro = false;
6056 FOR_EACH_EDGE (e, ei, bb->preds)
6058 if (bitmap_bit_p (&bb_flags, e->src->index))
6063 if (some_pro && some_no_pro)
6064 VEC_quick_push (basic_block, vec, bb);
6066 bitmap_clear_bit (&bb_tail, bb->index);
6068 /* Find the head of each tail. */
6069 while (!VEC_empty (basic_block, vec))
6071 basic_block tbb = VEC_pop (basic_block, vec);
6073 if (!bitmap_bit_p (&bb_tail, tbb->index))
6076 while (single_succ_p (tbb))
6078 tbb = single_succ (tbb);
6079 bitmap_clear_bit (&bb_tail, tbb->index);
6082 /* Now duplicate the tails. */
6083 if (!bitmap_empty_p (&bb_tail))
6084 FOR_EACH_BB_REVERSE (bb)
6086 basic_block copy_bb, tbb;
6090 if (!bitmap_clear_bit (&bb_tail, bb->index))
6093 /* Create a copy of BB, instructions and all, for
6094 use on paths that don't need a prologue.
6095 Ideal placement of the copy is on a fall-thru edge
6096 or after a block that would jump to the copy. */
6097 FOR_EACH_EDGE (e, ei, bb->preds)
6098 if (!bitmap_bit_p (&bb_flags, e->src->index)
6099 && single_succ_p (e->src))
6103 copy_bb = create_basic_block (NEXT_INSN (BB_END (e->src)),
6105 BB_COPY_PARTITION (copy_bb, e->src);
6109 /* Otherwise put the copy at the end of the function. */
6110 copy_bb = create_basic_block (NULL_RTX, NULL_RTX,
6111 EXIT_BLOCK_PTR->prev_bb);
6112 BB_COPY_PARTITION (copy_bb, bb);
6115 insert_point = emit_note_after (NOTE_INSN_DELETED,
6117 emit_barrier_after (BB_END (copy_bb));
6122 dup_block_and_redirect (tbb, copy_bb, insert_point,
6124 tbb = single_succ (tbb);
6125 if (tbb == EXIT_BLOCK_PTR)
6127 e = split_block (copy_bb, PREV_INSN (insert_point));
6131 /* Quiet verify_flow_info by (ab)using EDGE_FAKE.
6132 We have yet to add a simple_return to the tails,
6133 as we'd like to first convert_jumps_to_returns in
6134 case the block is no longer used after that. */
6136 if (CALL_P (PREV_INSN (insert_point))
6137 && SIBLING_CALL_P (PREV_INSN (insert_point)))
6138 eflags = EDGE_SIBCALL | EDGE_ABNORMAL;
6139 make_single_succ_edge (copy_bb, EXIT_BLOCK_PTR, eflags);
6141 /* verify_flow_info doesn't like a note after a
6143 delete_insn (insert_point);
6144 if (bitmap_empty_p (&bb_tail))
6150 bitmap_clear (&bb_tail);
6151 bitmap_clear (&bb_antic_flags);
6152 bitmap_clear (&bb_on_list);
6153 VEC_free (basic_block, heap, vec);
6157 if (split_prologue_seq != NULL_RTX)
6159 insert_insn_on_edge (split_prologue_seq, orig_entry_edge);
6162 if (prologue_seq != NULL_RTX)
6164 insert_insn_on_edge (prologue_seq, entry_edge);
6168 /* If the exit block has no non-fake predecessors, we don't need
6170 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
6171 if ((e->flags & EDGE_FAKE) == 0)
6176 rtl_profile_for_bb (EXIT_BLOCK_PTR);
6178 exit_fallthru_edge = find_fallthru_edge (EXIT_BLOCK_PTR->preds);
6180 /* If we're allowed to generate a simple return instruction, then by
6181 definition we don't need a full epilogue. If the last basic
6182 block before the exit block does not contain active instructions,
6183 examine its predecessors and try to emit (conditional) return
6185 #ifdef HAVE_simple_return
6186 if (entry_edge != orig_entry_edge)
6192 /* convert_jumps_to_returns may add to EXIT_BLOCK_PTR->preds
6193 (but won't remove). Stop at end of current preds. */
6194 last = EDGE_COUNT (EXIT_BLOCK_PTR->preds);
6195 for (i = 0; i < last; i++)
6197 e = EDGE_I (EXIT_BLOCK_PTR->preds, i);
6198 if (LABEL_P (BB_HEAD (e->src))
6199 && !bitmap_bit_p (&bb_flags, e->src->index)
6200 && !active_insn_between (BB_HEAD (e->src), BB_END (e->src)))
6201 unconverted_simple_returns
6202 = convert_jumps_to_returns (e->src, true,
6203 unconverted_simple_returns);
6207 if (exit_fallthru_edge != NULL
6208 && EDGE_COUNT (exit_fallthru_edge->src->preds) != 0
6209 && !bitmap_bit_p (&bb_flags, exit_fallthru_edge->src->index))
6211 basic_block last_bb;
6213 last_bb = emit_return_for_exit (exit_fallthru_edge, true);
6214 returnjump = BB_END (last_bb);
6215 exit_fallthru_edge = NULL;
6222 if (exit_fallthru_edge == NULL)
6227 basic_block last_bb = exit_fallthru_edge->src;
6229 if (LABEL_P (BB_HEAD (last_bb))
6230 && !active_insn_between (BB_HEAD (last_bb), BB_END (last_bb)))
6231 convert_jumps_to_returns (last_bb, false, NULL);
6233 if (EDGE_COUNT (last_bb->preds) != 0
6234 && single_succ_p (last_bb))
6236 last_bb = emit_return_for_exit (exit_fallthru_edge, false);
6237 epilogue_end = returnjump = BB_END (last_bb);
6238 #ifdef HAVE_simple_return
6239 /* Emitting the return may add a basic block.
6240 Fix bb_flags for the added block. */
6241 if (last_bb != exit_fallthru_edge->src)
6242 bitmap_set_bit (&bb_flags, last_bb->index);
6250 /* A small fib -- epilogue is not yet completed, but we wish to re-use
6251 this marker for the splits of EH_RETURN patterns, and nothing else
6252 uses the flag in the meantime. */
6253 epilogue_completed = 1;
6255 #ifdef HAVE_eh_return
6256 /* Find non-fallthru edges that end with EH_RETURN instructions. On
6257 some targets, these get split to a special version of the epilogue
6258 code. In order to be able to properly annotate these with unwind
6259 info, try to split them now. If we get a valid split, drop an
6260 EPILOGUE_BEG note and mark the insns as epilogue insns. */
6261 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
6263 rtx prev, last, trial;
6265 if (e->flags & EDGE_FALLTHRU)
6267 last = BB_END (e->src);
6268 if (!eh_returnjump_p (last))
6271 prev = PREV_INSN (last);
6272 trial = try_split (PATTERN (last), last, 1);
6276 record_insns (NEXT_INSN (prev), NEXT_INSN (trial), &epilogue_insn_hash);
6277 emit_note_after (NOTE_INSN_EPILOGUE_BEG, prev);
6281 /* If nothing falls through into the exit block, we don't need an
6284 if (exit_fallthru_edge == NULL)
6287 #ifdef HAVE_epilogue
6291 epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG);
6292 seq = gen_epilogue ();
6294 emit_jump_insn (seq);
6296 /* Retain a map of the epilogue insns. */
6297 record_insns (seq, NULL, &epilogue_insn_hash);
6298 set_insn_locators (seq, epilogue_locator);
6301 returnjump = get_last_insn ();
6304 insert_insn_on_edge (seq, exit_fallthru_edge);
6307 if (JUMP_P (returnjump))
6308 set_return_jump_label (returnjump);
6315 if (! next_active_insn (BB_END (exit_fallthru_edge->src)))
6317 /* We have a fall-through edge to the exit block, the source is not
6318 at the end of the function, and there will be an assembler epilogue
6319 at the end of the function.
6320 We can't use force_nonfallthru here, because that would try to
6321 use return. Inserting a jump 'by hand' is extremely messy, so
6322 we take advantage of cfg_layout_finalize using
6323 fixup_fallthru_exit_predecessor. */
6324 cfg_layout_initialize (0);
6325 FOR_EACH_BB (cur_bb)
6326 if (cur_bb->index >= NUM_FIXED_BLOCKS
6327 && cur_bb->next_bb->index >= NUM_FIXED_BLOCKS)
6328 cur_bb->aux = cur_bb->next_bb;
6329 cfg_layout_finalize ();
6334 default_rtl_profile ();
6340 commit_edge_insertions ();
6342 /* Look for basic blocks within the prologue insns. */
6343 blocks = sbitmap_alloc (last_basic_block);
6344 sbitmap_zero (blocks);
6345 SET_BIT (blocks, entry_edge->dest->index);
6346 SET_BIT (blocks, orig_entry_edge->dest->index);
6347 find_many_sub_basic_blocks (blocks);
6348 sbitmap_free (blocks);
6350 /* The epilogue insns we inserted may cause the exit edge to no longer
6352 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
6354 if (((e->flags & EDGE_FALLTHRU) != 0)
6355 && returnjump_p (BB_END (e->src)))
6356 e->flags &= ~EDGE_FALLTHRU;
6360 #ifdef HAVE_simple_return
6361 /* If there were branches to an empty LAST_BB which we tried to
6362 convert to conditional simple_returns, but couldn't for some
6363 reason, create a block to hold a simple_return insn and redirect
6364 those remaining edges. */
6365 if (!VEC_empty (edge, unconverted_simple_returns))
6367 basic_block simple_return_block_hot = NULL;
6368 basic_block simple_return_block_cold = NULL;
6369 edge pending_edge_hot = NULL;
6370 edge pending_edge_cold = NULL;
6371 basic_block exit_pred = EXIT_BLOCK_PTR->prev_bb;
6374 gcc_assert (entry_edge != orig_entry_edge);
6376 /* See if we can reuse the last insn that was emitted for the
6378 if (returnjump != NULL_RTX
6379 && JUMP_LABEL (returnjump) == simple_return_rtx)
6381 e = split_block (BLOCK_FOR_INSN (returnjump), PREV_INSN (returnjump));
6382 if (BB_PARTITION (e->src) == BB_HOT_PARTITION)
6383 simple_return_block_hot = e->dest;
6385 simple_return_block_cold = e->dest;
6388 /* Also check returns we might need to add to tail blocks. */
6389 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
6390 if (EDGE_COUNT (e->src->preds) != 0
6391 && (e->flags & EDGE_FAKE) != 0
6392 && !bitmap_bit_p (&bb_flags, e->src->index))
6394 if (BB_PARTITION (e->src) == BB_HOT_PARTITION)
6395 pending_edge_hot = e;
6397 pending_edge_cold = e;
6400 FOR_EACH_VEC_ELT (edge, unconverted_simple_returns, i, e)
6402 basic_block *pdest_bb;
6405 if (BB_PARTITION (e->src) == BB_HOT_PARTITION)
6407 pdest_bb = &simple_return_block_hot;
6408 pending = pending_edge_hot;
6412 pdest_bb = &simple_return_block_cold;
6413 pending = pending_edge_cold;
6416 if (*pdest_bb == NULL && pending != NULL)
6418 emit_return_into_block (true, pending->src);
6419 pending->flags &= ~(EDGE_FALLTHRU | EDGE_FAKE);
6420 *pdest_bb = pending->src;
6422 else if (*pdest_bb == NULL)
6427 bb = create_basic_block (NULL, NULL, exit_pred);
6428 BB_COPY_PARTITION (bb, e->src);
6429 start = emit_jump_insn_after (gen_simple_return (),
6431 JUMP_LABEL (start) = simple_return_rtx;
6432 emit_barrier_after (start);
6435 make_edge (bb, EXIT_BLOCK_PTR, 0);
6437 redirect_edge_and_branch_force (e, *pdest_bb);
6439 VEC_free (edge, heap, unconverted_simple_returns);
6442 if (entry_edge != orig_entry_edge)
6444 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
6445 if (EDGE_COUNT (e->src->preds) != 0
6446 && (e->flags & EDGE_FAKE) != 0
6447 && !bitmap_bit_p (&bb_flags, e->src->index))
6449 emit_return_into_block (true, e->src);
6450 e->flags &= ~(EDGE_FALLTHRU | EDGE_FAKE);
6455 #ifdef HAVE_sibcall_epilogue
6456 /* Emit sibling epilogues before any sibling call sites. */
6457 for (ei = ei_start (EXIT_BLOCK_PTR->preds); (e = ei_safe_edge (ei)); )
6459 basic_block bb = e->src;
6460 rtx insn = BB_END (bb);
6464 || ! SIBLING_CALL_P (insn)
6465 #ifdef HAVE_simple_return
6466 || (entry_edge != orig_entry_edge
6467 && !bitmap_bit_p (&bb_flags, bb->index))
6475 ep_seq = gen_sibcall_epilogue ();
6479 emit_note (NOTE_INSN_EPILOGUE_BEG);
6484 /* Retain a map of the epilogue insns. Used in life analysis to
6485 avoid getting rid of sibcall epilogue insns. Do this before we
6486 actually emit the sequence. */
6487 record_insns (seq, NULL, &epilogue_insn_hash);
6488 set_insn_locators (seq, epilogue_locator);
6490 emit_insn_before (seq, insn);
6496 #ifdef HAVE_epilogue
6501 /* Similarly, move any line notes that appear after the epilogue.
6502 There is no need, however, to be quite so anal about the existence
6503 of such a note. Also possibly move
6504 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
6506 for (insn = epilogue_end; insn; insn = next)
6508 next = NEXT_INSN (insn);
6510 && (NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG))
6511 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
6516 #ifdef HAVE_simple_return
6517 bitmap_clear (&bb_flags);
6520 /* Threading the prologue and epilogue changes the artificial refs
6521 in the entry and exit blocks. */
6522 epilogue_completed = 1;
6523 df_update_entry_exit_and_calls ();
6526 /* Reposition the prologue-end and epilogue-begin notes after
6527 instruction scheduling. */
6530 reposition_prologue_and_epilogue_notes (void)
6532 #if defined (HAVE_prologue) || defined (HAVE_epilogue) \
6533 || defined (HAVE_sibcall_epilogue)
6534 /* Since the hash table is created on demand, the fact that it is
6535 non-null is a signal that it is non-empty. */
6536 if (prologue_insn_hash != NULL)
6538 size_t len = htab_elements (prologue_insn_hash);
6539 rtx insn, last = NULL, note = NULL;
6541 /* Scan from the beginning until we reach the last prologue insn. */
6542 /* ??? While we do have the CFG intact, there are two problems:
6543 (1) The prologue can contain loops (typically probing the stack),
6544 which means that the end of the prologue isn't in the first bb.
6545 (2) Sometimes the PROLOGUE_END note gets pushed into the next bb. */
6546 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6550 if (NOTE_KIND (insn) == NOTE_INSN_PROLOGUE_END)
6553 else if (contains (insn, prologue_insn_hash))
6565 /* Scan forward looking for the PROLOGUE_END note. It should
6566 be right at the beginning of the block, possibly with other
6567 insn notes that got moved there. */
6568 for (note = NEXT_INSN (last); ; note = NEXT_INSN (note))
6571 && NOTE_KIND (note) == NOTE_INSN_PROLOGUE_END)
6576 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
6578 last = NEXT_INSN (last);
6579 reorder_insns (note, note, last);
6583 if (epilogue_insn_hash != NULL)
6588 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
6590 rtx insn, first = NULL, note = NULL;
6591 basic_block bb = e->src;
6593 /* Scan from the beginning until we reach the first epilogue insn. */
6594 FOR_BB_INSNS (bb, insn)
6598 if (NOTE_KIND (insn) == NOTE_INSN_EPILOGUE_BEG)
6605 else if (first == NULL && contains (insn, epilogue_insn_hash))
6615 /* If the function has a single basic block, and no real
6616 epilogue insns (e.g. sibcall with no cleanup), the
6617 epilogue note can get scheduled before the prologue
6618 note. If we have frame related prologue insns, having
6619 them scanned during the epilogue will result in a crash.
6620 In this case re-order the epilogue note to just before
6621 the last insn in the block. */
6623 first = BB_END (bb);
6625 if (PREV_INSN (first) != note)
6626 reorder_insns (note, note, PREV_INSN (first));
6630 #endif /* HAVE_prologue or HAVE_epilogue */
6633 /* Returns the name of the current function. */
6635 current_function_name (void)
6639 return lang_hooks.decl_printable_name (cfun->decl, 2);
6644 rest_of_handle_check_leaf_regs (void)
6646 #ifdef LEAF_REGISTERS
6647 current_function_uses_only_leaf_regs
6648 = optimize > 0 && only_leaf_regs_used () && leaf_function_p ();
6653 /* Insert a TYPE into the used types hash table of CFUN. */
6656 used_types_insert_helper (tree type, struct function *func)
6658 if (type != NULL && func != NULL)
6662 if (func->used_types_hash == NULL)
6663 func->used_types_hash = htab_create_ggc (37, htab_hash_pointer,
6664 htab_eq_pointer, NULL);
6665 slot = htab_find_slot (func->used_types_hash, type, INSERT);
6671 /* Given a type, insert it into the used hash table in cfun. */
6673 used_types_insert (tree t)
6675 while (POINTER_TYPE_P (t) || TREE_CODE (t) == ARRAY_TYPE)
6680 if (TREE_CODE (t) == ERROR_MARK)
6682 if (TYPE_NAME (t) == NULL_TREE
6683 || TYPE_NAME (t) == TYPE_NAME (TYPE_MAIN_VARIANT (t)))
6684 t = TYPE_MAIN_VARIANT (t);
6685 if (debug_info_level > DINFO_LEVEL_NONE)
6688 used_types_insert_helper (t, cfun);
6690 /* So this might be a type referenced by a global variable.
6691 Record that type so that we can later decide to emit its debug
6693 VEC_safe_push (tree, gc, types_used_by_cur_var_decl, t);
6697 /* Helper to Hash a struct types_used_by_vars_entry. */
6700 hash_types_used_by_vars_entry (const struct types_used_by_vars_entry *entry)
6702 gcc_assert (entry && entry->var_decl && entry->type);
6704 return iterative_hash_object (entry->type,
6705 iterative_hash_object (entry->var_decl, 0));
6708 /* Hash function of the types_used_by_vars_entry hash table. */
6711 types_used_by_vars_do_hash (const void *x)
6713 const struct types_used_by_vars_entry *entry =
6714 (const struct types_used_by_vars_entry *) x;
6716 return hash_types_used_by_vars_entry (entry);
6719 /*Equality function of the types_used_by_vars_entry hash table. */
6722 types_used_by_vars_eq (const void *x1, const void *x2)
6724 const struct types_used_by_vars_entry *e1 =
6725 (const struct types_used_by_vars_entry *) x1;
6726 const struct types_used_by_vars_entry *e2 =
6727 (const struct types_used_by_vars_entry *)x2;
6729 return (e1->var_decl == e2->var_decl && e1->type == e2->type);
6732 /* Inserts an entry into the types_used_by_vars_hash hash table. */
6735 types_used_by_var_decl_insert (tree type, tree var_decl)
6737 if (type != NULL && var_decl != NULL)
6740 struct types_used_by_vars_entry e;
6741 e.var_decl = var_decl;
6743 if (types_used_by_vars_hash == NULL)
6744 types_used_by_vars_hash =
6745 htab_create_ggc (37, types_used_by_vars_do_hash,
6746 types_used_by_vars_eq, NULL);
6747 slot = htab_find_slot_with_hash (types_used_by_vars_hash, &e,
6748 hash_types_used_by_vars_entry (&e), INSERT);
6751 struct types_used_by_vars_entry *entry;
6752 entry = ggc_alloc_types_used_by_vars_entry ();
6754 entry->var_decl = var_decl;
6760 struct rtl_opt_pass pass_leaf_regs =
6764 "*leaf_regs", /* name */
6766 rest_of_handle_check_leaf_regs, /* execute */
6769 0, /* static_pass_number */
6770 TV_NONE, /* tv_id */
6771 0, /* properties_required */
6772 0, /* properties_provided */
6773 0, /* properties_destroyed */
6774 0, /* todo_flags_start */
6775 0 /* todo_flags_finish */
6780 rest_of_handle_thread_prologue_and_epilogue (void)
6783 cleanup_cfg (CLEANUP_EXPENSIVE);
6785 /* On some machines, the prologue and epilogue code, or parts thereof,
6786 can be represented as RTL. Doing so lets us schedule insns between
6787 it and the rest of the code and also allows delayed branch
6788 scheduling to operate in the epilogue. */
6789 thread_prologue_and_epilogue_insns ();
6791 /* The stack usage info is finalized during prologue expansion. */
6792 if (flag_stack_usage_info)
6793 output_stack_usage ();
6798 struct rtl_opt_pass pass_thread_prologue_and_epilogue =
6802 "pro_and_epilogue", /* name */
6804 rest_of_handle_thread_prologue_and_epilogue, /* execute */
6807 0, /* static_pass_number */
6808 TV_THREAD_PROLOGUE_AND_EPILOGUE, /* tv_id */
6809 0, /* properties_required */
6810 0, /* properties_provided */
6811 0, /* properties_destroyed */
6812 TODO_verify_flow, /* todo_flags_start */
6814 TODO_df_finish | TODO_verify_rtl_sharing |
6815 TODO_ggc_collect /* todo_flags_finish */
6820 /* This mini-pass fixes fall-out from SSA in asm statements that have
6821 in-out constraints. Say you start with
6824 asm ("": "+mr" (inout));
6827 which is transformed very early to use explicit output and match operands:
6830 asm ("": "=mr" (inout) : "0" (inout));
6833 Or, after SSA and copyprop,
6835 asm ("": "=mr" (inout_2) : "0" (inout_1));
6838 Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
6839 they represent two separate values, so they will get different pseudo
6840 registers during expansion. Then, since the two operands need to match
6841 per the constraints, but use different pseudo registers, reload can
6842 only register a reload for these operands. But reloads can only be
6843 satisfied by hardregs, not by memory, so we need a register for this
6844 reload, just because we are presented with non-matching operands.
6845 So, even though we allow memory for this operand, no memory can be
6846 used for it, just because the two operands don't match. This can
6847 cause reload failures on register-starved targets.
6849 So it's a symptom of reload not being able to use memory for reloads
6850 or, alternatively it's also a symptom of both operands not coming into
6851 reload as matching (in which case the pseudo could go to memory just
6852 fine, as the alternative allows it, and no reload would be necessary).
6853 We fix the latter problem here, by transforming
6855 asm ("": "=mr" (inout_2) : "0" (inout_1));
6860 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
6863 match_asm_constraints_1 (rtx insn, rtx *p_sets, int noutputs)
6866 bool changed = false;
6867 rtx op = SET_SRC (p_sets[0]);
6868 int ninputs = ASM_OPERANDS_INPUT_LENGTH (op);
6869 rtvec inputs = ASM_OPERANDS_INPUT_VEC (op);
6870 bool *output_matched = XALLOCAVEC (bool, noutputs);
6872 memset (output_matched, 0, noutputs * sizeof (bool));
6873 for (i = 0; i < ninputs; i++)
6875 rtx input, output, insns;
6876 const char *constraint = ASM_OPERANDS_INPUT_CONSTRAINT (op, i);
6880 if (*constraint == '%')
6883 match = strtoul (constraint, &end, 10);
6884 if (end == constraint)
6887 gcc_assert (match < noutputs);
6888 output = SET_DEST (p_sets[match]);
6889 input = RTVEC_ELT (inputs, i);
6890 /* Only do the transformation for pseudos. */
6891 if (! REG_P (output)
6892 || rtx_equal_p (output, input)
6893 || (GET_MODE (input) != VOIDmode
6894 && GET_MODE (input) != GET_MODE (output)))
6897 /* We can't do anything if the output is also used as input,
6898 as we're going to overwrite it. */
6899 for (j = 0; j < ninputs; j++)
6900 if (reg_overlap_mentioned_p (output, RTVEC_ELT (inputs, j)))
6905 /* Avoid changing the same input several times. For
6906 asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
6907 only change in once (to out1), rather than changing it
6908 first to out1 and afterwards to out2. */
6911 for (j = 0; j < noutputs; j++)
6912 if (output_matched[j] && input == SET_DEST (p_sets[j]))
6917 output_matched[match] = true;
6920 emit_move_insn (output, input);
6921 insns = get_insns ();
6923 emit_insn_before (insns, insn);
6925 /* Now replace all mentions of the input with output. We can't
6926 just replace the occurrence in inputs[i], as the register might
6927 also be used in some other input (or even in an address of an
6928 output), which would mean possibly increasing the number of
6929 inputs by one (namely 'output' in addition), which might pose
6930 a too complicated problem for reload to solve. E.g. this situation:
6932 asm ("" : "=r" (output), "=m" (input) : "0" (input))
6934 Here 'input' is used in two occurrences as input (once for the
6935 input operand, once for the address in the second output operand).
6936 If we would replace only the occurrence of the input operand (to
6937 make the matching) we would be left with this:
6940 asm ("" : "=r" (output), "=m" (input) : "0" (output))
6942 Now we suddenly have two different input values (containing the same
6943 value, but different pseudos) where we formerly had only one.
6944 With more complicated asms this might lead to reload failures
6945 which wouldn't have happen without this pass. So, iterate over
6946 all operands and replace all occurrences of the register used. */
6947 for (j = 0; j < noutputs; j++)
6948 if (!rtx_equal_p (SET_DEST (p_sets[j]), input)
6949 && reg_overlap_mentioned_p (input, SET_DEST (p_sets[j])))
6950 SET_DEST (p_sets[j]) = replace_rtx (SET_DEST (p_sets[j]),
6952 for (j = 0; j < ninputs; j++)
6953 if (reg_overlap_mentioned_p (input, RTVEC_ELT (inputs, j)))
6954 RTVEC_ELT (inputs, j) = replace_rtx (RTVEC_ELT (inputs, j),
6961 df_insn_rescan (insn);
6965 rest_of_match_asm_constraints (void)
6968 rtx insn, pat, *p_sets;
6971 if (!crtl->has_asm_statement)
6974 df_set_flags (DF_DEFER_INSN_RESCAN);
6977 FOR_BB_INSNS (bb, insn)
6982 pat = PATTERN (insn);
6983 if (GET_CODE (pat) == PARALLEL)
6984 p_sets = &XVECEXP (pat, 0, 0), noutputs = XVECLEN (pat, 0);
6985 else if (GET_CODE (pat) == SET)
6986 p_sets = &PATTERN (insn), noutputs = 1;
6990 if (GET_CODE (*p_sets) == SET
6991 && GET_CODE (SET_SRC (*p_sets)) == ASM_OPERANDS)
6992 match_asm_constraints_1 (insn, p_sets, noutputs);
6996 return TODO_df_finish;
6999 struct rtl_opt_pass pass_match_asm_constraints =
7003 "asmcons", /* name */
7005 rest_of_match_asm_constraints, /* execute */
7008 0, /* static_pass_number */
7009 TV_NONE, /* tv_id */
7010 0, /* properties_required */
7011 0, /* properties_provided */
7012 0, /* properties_destroyed */
7013 0, /* todo_flags_start */
7014 0 /* todo_flags_finish */
7019 #include "gt-function.h"