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 "cfglayout.h"
62 #include "tree-pass.h"
68 /* So we can assign to cfun in this file. */
71 #ifndef STACK_ALIGNMENT_NEEDED
72 #define STACK_ALIGNMENT_NEEDED 1
75 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
77 /* Some systems use __main in a way incompatible with its use in gcc, in these
78 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
79 give the same symbol without quotes for an alternative entry point. You
80 must define both, or neither. */
82 #define NAME__MAIN "__main"
85 /* Round a value to the lowest integer less than it that is a multiple of
86 the required alignment. Avoid using division in case the value is
87 negative. Assume the alignment is a power of two. */
88 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
90 /* Similar, but round to the next highest integer that meets the
92 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
94 /* Nonzero if function being compiled doesn't contain any calls
95 (ignoring the prologue and epilogue). This is set prior to
96 local register allocation and is valid for the remaining
98 int current_function_is_leaf;
100 /* Nonzero if function being compiled doesn't modify the stack pointer
101 (ignoring the prologue and epilogue). This is only valid after
102 pass_stack_ptr_mod has run. */
103 int current_function_sp_is_unchanging;
105 /* Nonzero if the function being compiled is a leaf function which only
106 uses leaf registers. This is valid after reload (specifically after
107 sched2) and is useful only if the port defines LEAF_REGISTERS. */
108 int current_function_uses_only_leaf_regs;
110 /* Nonzero once virtual register instantiation has been done.
111 assign_stack_local uses frame_pointer_rtx when this is nonzero.
112 calls.c:emit_library_call_value_1 uses it to set up
113 post-instantiation libcalls. */
114 int virtuals_instantiated;
116 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
117 static GTY(()) int funcdef_no;
119 /* These variables hold pointers to functions to create and destroy
120 target specific, per-function data structures. */
121 struct machine_function * (*init_machine_status) (void);
123 /* The currently compiled function. */
124 struct function *cfun = 0;
126 /* These hashes record the prologue and epilogue insns. */
127 static GTY((if_marked ("ggc_marked_p"), param_is (struct rtx_def)))
128 htab_t prologue_insn_hash;
129 static GTY((if_marked ("ggc_marked_p"), param_is (struct rtx_def)))
130 htab_t epilogue_insn_hash;
133 htab_t types_used_by_vars_hash = NULL;
134 VEC(tree,gc) *types_used_by_cur_var_decl;
136 /* Forward declarations. */
138 static struct temp_slot *find_temp_slot_from_address (rtx);
139 static void pad_to_arg_alignment (struct args_size *, int, struct args_size *);
140 static void pad_below (struct args_size *, enum machine_mode, tree);
141 static void reorder_blocks_1 (rtx, tree, VEC(tree,heap) **);
142 static int all_blocks (tree, tree *);
143 static tree *get_block_vector (tree, int *);
144 extern tree debug_find_var_in_block_tree (tree, tree);
145 /* We always define `record_insns' even if it's not used so that we
146 can always export `prologue_epilogue_contains'. */
147 static void record_insns (rtx, rtx, htab_t *) ATTRIBUTE_UNUSED;
148 static bool contains (const_rtx, htab_t);
150 static void emit_return_into_block (basic_block);
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 if (crtl->emit.regno_pointer_align)
215 free (crtl->emit.regno_pointer_align);
217 memset (crtl, 0, sizeof (struct rtl_data));
222 regno_reg_rtx = NULL;
223 insn_locators_free ();
226 /* Return size needed for stack frame based on slots so far allocated.
227 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
228 the caller may have to do that. */
231 get_frame_size (void)
233 if (FRAME_GROWS_DOWNWARD)
234 return -frame_offset;
239 /* Issue an error message and return TRUE if frame OFFSET overflows in
240 the signed target pointer arithmetics for function FUNC. Otherwise
244 frame_offset_overflow (HOST_WIDE_INT offset, tree func)
246 unsigned HOST_WIDE_INT size = FRAME_GROWS_DOWNWARD ? -offset : offset;
248 if (size > ((unsigned HOST_WIDE_INT) 1 << (GET_MODE_BITSIZE (Pmode) - 1))
249 /* Leave room for the fixed part of the frame. */
250 - 64 * UNITS_PER_WORD)
252 error_at (DECL_SOURCE_LOCATION (func),
253 "total size of local objects too large");
260 /* Return stack slot alignment in bits for TYPE and MODE. */
263 get_stack_local_alignment (tree type, enum machine_mode mode)
265 unsigned int alignment;
268 alignment = BIGGEST_ALIGNMENT;
270 alignment = GET_MODE_ALIGNMENT (mode);
272 /* Allow the frond-end to (possibly) increase the alignment of this
275 type = lang_hooks.types.type_for_mode (mode, 0);
277 return STACK_SLOT_ALIGNMENT (type, mode, alignment);
280 /* Determine whether it is possible to fit a stack slot of size SIZE and
281 alignment ALIGNMENT into an area in the stack frame that starts at
282 frame offset START and has a length of LENGTH. If so, store the frame
283 offset to be used for the stack slot in *POFFSET and return true;
284 return false otherwise. This function will extend the frame size when
285 given a start/length pair that lies at the end of the frame. */
288 try_fit_stack_local (HOST_WIDE_INT start, HOST_WIDE_INT length,
289 HOST_WIDE_INT size, unsigned int alignment,
290 HOST_WIDE_INT *poffset)
292 HOST_WIDE_INT this_frame_offset;
293 int frame_off, frame_alignment, frame_phase;
295 /* Calculate how many bytes the start of local variables is off from
297 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
298 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
299 frame_phase = frame_off ? frame_alignment - frame_off : 0;
301 /* Round the frame offset to the specified alignment. */
303 /* We must be careful here, since FRAME_OFFSET might be negative and
304 division with a negative dividend isn't as well defined as we might
305 like. So we instead assume that ALIGNMENT is a power of two and
306 use logical operations which are unambiguous. */
307 if (FRAME_GROWS_DOWNWARD)
309 = (FLOOR_ROUND (start + length - size - frame_phase,
310 (unsigned HOST_WIDE_INT) alignment)
314 = (CEIL_ROUND (start - frame_phase,
315 (unsigned HOST_WIDE_INT) alignment)
318 /* See if it fits. If this space is at the edge of the frame,
319 consider extending the frame to make it fit. Our caller relies on
320 this when allocating a new slot. */
321 if (frame_offset == start && this_frame_offset < frame_offset)
322 frame_offset = this_frame_offset;
323 else if (this_frame_offset < start)
325 else if (start + length == frame_offset
326 && this_frame_offset + size > start + length)
327 frame_offset = this_frame_offset + size;
328 else if (this_frame_offset + size > start + length)
331 *poffset = this_frame_offset;
335 /* Create a new frame_space structure describing free space in the stack
336 frame beginning at START and ending at END, and chain it into the
337 function's frame_space_list. */
340 add_frame_space (HOST_WIDE_INT start, HOST_WIDE_INT end)
342 struct frame_space *space = ggc_alloc_frame_space ();
343 space->next = crtl->frame_space_list;
344 crtl->frame_space_list = space;
345 space->start = start;
346 space->length = end - start;
349 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
350 with machine mode MODE.
352 ALIGN controls the amount of alignment for the address of the slot:
353 0 means according to MODE,
354 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
355 -2 means use BITS_PER_UNIT,
356 positive specifies alignment boundary in bits.
358 KIND has ASLK_REDUCE_ALIGN bit set if it is OK to reduce
359 alignment and ASLK_RECORD_PAD bit set if we should remember
360 extra space we allocated for alignment purposes. When we are
361 called from assign_stack_temp_for_type, it is not set so we don't
362 track the same stack slot in two independent lists.
364 We do not round to stack_boundary here. */
367 assign_stack_local_1 (enum machine_mode mode, HOST_WIDE_INT size,
371 int bigend_correction = 0;
372 HOST_WIDE_INT slot_offset = 0, old_frame_offset;
373 unsigned int alignment, alignment_in_bits;
377 alignment = get_stack_local_alignment (NULL, mode);
378 alignment /= BITS_PER_UNIT;
380 else if (align == -1)
382 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
383 size = CEIL_ROUND (size, alignment);
385 else if (align == -2)
386 alignment = 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
388 alignment = align / BITS_PER_UNIT;
390 alignment_in_bits = alignment * BITS_PER_UNIT;
392 /* Ignore alignment if it exceeds MAX_SUPPORTED_STACK_ALIGNMENT. */
393 if (alignment_in_bits > MAX_SUPPORTED_STACK_ALIGNMENT)
395 alignment_in_bits = MAX_SUPPORTED_STACK_ALIGNMENT;
396 alignment = alignment_in_bits / BITS_PER_UNIT;
399 if (SUPPORTS_STACK_ALIGNMENT)
401 if (crtl->stack_alignment_estimated < alignment_in_bits)
403 if (!crtl->stack_realign_processed)
404 crtl->stack_alignment_estimated = alignment_in_bits;
407 /* If stack is realigned and stack alignment value
408 hasn't been finalized, it is OK not to increase
409 stack_alignment_estimated. The bigger alignment
410 requirement is recorded in stack_alignment_needed
412 gcc_assert (!crtl->stack_realign_finalized);
413 if (!crtl->stack_realign_needed)
415 /* It is OK to reduce the alignment as long as the
416 requested size is 0 or the estimated stack
417 alignment >= mode alignment. */
418 gcc_assert ((kind & ASLK_REDUCE_ALIGN)
420 || (crtl->stack_alignment_estimated
421 >= GET_MODE_ALIGNMENT (mode)));
422 alignment_in_bits = crtl->stack_alignment_estimated;
423 alignment = alignment_in_bits / BITS_PER_UNIT;
429 if (crtl->stack_alignment_needed < alignment_in_bits)
430 crtl->stack_alignment_needed = alignment_in_bits;
431 if (crtl->max_used_stack_slot_alignment < alignment_in_bits)
432 crtl->max_used_stack_slot_alignment = alignment_in_bits;
434 if (mode != BLKmode || size != 0)
436 if (kind & ASLK_RECORD_PAD)
438 struct frame_space **psp;
440 for (psp = &crtl->frame_space_list; *psp; psp = &(*psp)->next)
442 struct frame_space *space = *psp;
443 if (!try_fit_stack_local (space->start, space->length, size,
444 alignment, &slot_offset))
447 if (slot_offset > space->start)
448 add_frame_space (space->start, slot_offset);
449 if (slot_offset + size < space->start + space->length)
450 add_frame_space (slot_offset + size,
451 space->start + space->length);
456 else if (!STACK_ALIGNMENT_NEEDED)
458 slot_offset = frame_offset;
462 old_frame_offset = frame_offset;
464 if (FRAME_GROWS_DOWNWARD)
466 frame_offset -= size;
467 try_fit_stack_local (frame_offset, size, size, alignment, &slot_offset);
469 if (kind & ASLK_RECORD_PAD)
471 if (slot_offset > frame_offset)
472 add_frame_space (frame_offset, slot_offset);
473 if (slot_offset + size < old_frame_offset)
474 add_frame_space (slot_offset + size, old_frame_offset);
479 frame_offset += size;
480 try_fit_stack_local (old_frame_offset, size, size, alignment, &slot_offset);
482 if (kind & ASLK_RECORD_PAD)
484 if (slot_offset > old_frame_offset)
485 add_frame_space (old_frame_offset, slot_offset);
486 if (slot_offset + size < frame_offset)
487 add_frame_space (slot_offset + size, frame_offset);
492 /* On a big-endian machine, if we are allocating more space than we will use,
493 use the least significant bytes of those that are allocated. */
494 if (BYTES_BIG_ENDIAN && mode != BLKmode && GET_MODE_SIZE (mode) < size)
495 bigend_correction = size - GET_MODE_SIZE (mode);
497 /* If we have already instantiated virtual registers, return the actual
498 address relative to the frame pointer. */
499 if (virtuals_instantiated)
500 addr = plus_constant (frame_pointer_rtx,
502 (slot_offset + bigend_correction
503 + STARTING_FRAME_OFFSET, Pmode));
505 addr = plus_constant (virtual_stack_vars_rtx,
507 (slot_offset + bigend_correction,
510 x = gen_rtx_MEM (mode, addr);
511 set_mem_align (x, alignment_in_bits);
512 MEM_NOTRAP_P (x) = 1;
515 = gen_rtx_EXPR_LIST (VOIDmode, x, stack_slot_list);
517 if (frame_offset_overflow (frame_offset, current_function_decl))
523 /* Wrap up assign_stack_local_1 with last parameter as false. */
526 assign_stack_local (enum machine_mode mode, HOST_WIDE_INT size, int align)
528 return assign_stack_local_1 (mode, size, align, ASLK_RECORD_PAD);
532 /* In order to evaluate some expressions, such as function calls returning
533 structures in memory, we need to temporarily allocate stack locations.
534 We record each allocated temporary in the following structure.
536 Associated with each temporary slot is a nesting level. When we pop up
537 one level, all temporaries associated with the previous level are freed.
538 Normally, all temporaries are freed after the execution of the statement
539 in which they were created. However, if we are inside a ({...}) grouping,
540 the result may be in a temporary and hence must be preserved. If the
541 result could be in a temporary, we preserve it if we can determine which
542 one it is in. If we cannot determine which temporary may contain the
543 result, all temporaries are preserved. A temporary is preserved by
544 pretending it was allocated at the previous nesting level.
546 Automatic variables are also assigned temporary slots, at the nesting
547 level where they are defined. They are marked a "kept" so that
548 free_temp_slots will not free them. */
550 struct GTY(()) temp_slot {
551 /* Points to next temporary slot. */
552 struct temp_slot *next;
553 /* Points to previous temporary slot. */
554 struct temp_slot *prev;
555 /* The rtx to used to reference the slot. */
557 /* The size, in units, of the slot. */
559 /* The type of the object in the slot, or zero if it doesn't correspond
560 to a type. We use this to determine whether a slot can be reused.
561 It can be reused if objects of the type of the new slot will always
562 conflict with objects of the type of the old slot. */
564 /* The alignment (in bits) of the slot. */
566 /* Nonzero if this temporary is currently in use. */
568 /* Nonzero if this temporary has its address taken. */
570 /* Nesting level at which this slot is being used. */
572 /* Nonzero if this should survive a call to free_temp_slots. */
574 /* The offset of the slot from the frame_pointer, including extra space
575 for alignment. This info is for combine_temp_slots. */
576 HOST_WIDE_INT base_offset;
577 /* The size of the slot, including extra space for alignment. This
578 info is for combine_temp_slots. */
579 HOST_WIDE_INT full_size;
582 /* A table of addresses that represent a stack slot. The table is a mapping
583 from address RTXen to a temp slot. */
584 static GTY((param_is(struct temp_slot_address_entry))) htab_t temp_slot_address_table;
586 /* Entry for the above hash table. */
587 struct GTY(()) temp_slot_address_entry {
590 struct temp_slot *temp_slot;
593 /* Removes temporary slot TEMP from LIST. */
596 cut_slot_from_list (struct temp_slot *temp, struct temp_slot **list)
599 temp->next->prev = temp->prev;
601 temp->prev->next = temp->next;
605 temp->prev = temp->next = NULL;
608 /* Inserts temporary slot TEMP to LIST. */
611 insert_slot_to_list (struct temp_slot *temp, struct temp_slot **list)
615 (*list)->prev = temp;
620 /* Returns the list of used temp slots at LEVEL. */
622 static struct temp_slot **
623 temp_slots_at_level (int level)
625 if (level >= (int) VEC_length (temp_slot_p, used_temp_slots))
626 VEC_safe_grow_cleared (temp_slot_p, gc, used_temp_slots, level + 1);
628 return &(VEC_address (temp_slot_p, used_temp_slots)[level]);
631 /* Returns the maximal temporary slot level. */
634 max_slot_level (void)
636 if (!used_temp_slots)
639 return VEC_length (temp_slot_p, used_temp_slots) - 1;
642 /* Moves temporary slot TEMP to LEVEL. */
645 move_slot_to_level (struct temp_slot *temp, int level)
647 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
648 insert_slot_to_list (temp, temp_slots_at_level (level));
652 /* Make temporary slot TEMP available. */
655 make_slot_available (struct temp_slot *temp)
657 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
658 insert_slot_to_list (temp, &avail_temp_slots);
663 /* Compute the hash value for an address -> temp slot mapping.
664 The value is cached on the mapping entry. */
666 temp_slot_address_compute_hash (struct temp_slot_address_entry *t)
668 int do_not_record = 0;
669 return hash_rtx (t->address, GET_MODE (t->address),
670 &do_not_record, NULL, false);
673 /* Return the hash value for an address -> temp slot mapping. */
675 temp_slot_address_hash (const void *p)
677 const struct temp_slot_address_entry *t;
678 t = (const struct temp_slot_address_entry *) p;
682 /* Compare two address -> temp slot mapping entries. */
684 temp_slot_address_eq (const void *p1, const void *p2)
686 const struct temp_slot_address_entry *t1, *t2;
687 t1 = (const struct temp_slot_address_entry *) p1;
688 t2 = (const struct temp_slot_address_entry *) p2;
689 return exp_equiv_p (t1->address, t2->address, 0, true);
692 /* Add ADDRESS as an alias of TEMP_SLOT to the addess -> temp slot mapping. */
694 insert_temp_slot_address (rtx address, struct temp_slot *temp_slot)
697 struct temp_slot_address_entry *t = ggc_alloc_temp_slot_address_entry ();
698 t->address = address;
699 t->temp_slot = temp_slot;
700 t->hash = temp_slot_address_compute_hash (t);
701 slot = htab_find_slot_with_hash (temp_slot_address_table, t, t->hash, INSERT);
705 /* Remove an address -> temp slot mapping entry if the temp slot is
706 not in use anymore. Callback for remove_unused_temp_slot_addresses. */
708 remove_unused_temp_slot_addresses_1 (void **slot, void *data ATTRIBUTE_UNUSED)
710 const struct temp_slot_address_entry *t;
711 t = (const struct temp_slot_address_entry *) *slot;
712 if (! t->temp_slot->in_use)
717 /* Remove all mappings of addresses to unused temp slots. */
719 remove_unused_temp_slot_addresses (void)
721 htab_traverse (temp_slot_address_table,
722 remove_unused_temp_slot_addresses_1,
726 /* Find the temp slot corresponding to the object at address X. */
728 static struct temp_slot *
729 find_temp_slot_from_address (rtx x)
732 struct temp_slot_address_entry tmp, *t;
734 /* First try the easy way:
735 See if X exists in the address -> temp slot mapping. */
737 tmp.temp_slot = NULL;
738 tmp.hash = temp_slot_address_compute_hash (&tmp);
739 t = (struct temp_slot_address_entry *)
740 htab_find_with_hash (temp_slot_address_table, &tmp, tmp.hash);
744 /* If we have a sum involving a register, see if it points to a temp
746 if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 0))
747 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
749 else if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 1))
750 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
753 /* Last resort: Address is a virtual stack var address. */
754 if (GET_CODE (x) == PLUS
755 && XEXP (x, 0) == virtual_stack_vars_rtx
756 && CONST_INT_P (XEXP (x, 1)))
759 for (i = max_slot_level (); i >= 0; i--)
760 for (p = *temp_slots_at_level (i); p; p = p->next)
762 if (INTVAL (XEXP (x, 1)) >= p->base_offset
763 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size)
771 /* Allocate a temporary stack slot and record it for possible later
774 MODE is the machine mode to be given to the returned rtx.
776 SIZE is the size in units of the space required. We do no rounding here
777 since assign_stack_local will do any required rounding.
779 KEEP is 1 if this slot is to be retained after a call to
780 free_temp_slots. Automatic variables for a block are allocated
781 with this flag. KEEP values of 2 or 3 were needed respectively
782 for variables whose lifetime is controlled by CLEANUP_POINT_EXPRs
783 or for SAVE_EXPRs, but they are now unused.
785 TYPE is the type that will be used for the stack slot. */
788 assign_stack_temp_for_type (enum machine_mode mode, HOST_WIDE_INT size,
792 struct temp_slot *p, *best_p = 0, *selected = NULL, **pp;
795 /* If SIZE is -1 it means that somebody tried to allocate a temporary
796 of a variable size. */
797 gcc_assert (size != -1);
799 /* These are now unused. */
800 gcc_assert (keep <= 1);
802 align = get_stack_local_alignment (type, mode);
804 /* Try to find an available, already-allocated temporary of the proper
805 mode which meets the size and alignment requirements. Choose the
806 smallest one with the closest alignment.
808 If assign_stack_temp is called outside of the tree->rtl expansion,
809 we cannot reuse the stack slots (that may still refer to
810 VIRTUAL_STACK_VARS_REGNUM). */
811 if (!virtuals_instantiated)
813 for (p = avail_temp_slots; p; p = p->next)
815 if (p->align >= align && p->size >= size
816 && GET_MODE (p->slot) == mode
817 && objects_must_conflict_p (p->type, type)
818 && (best_p == 0 || best_p->size > p->size
819 || (best_p->size == p->size && best_p->align > p->align)))
821 if (p->align == align && p->size == size)
824 cut_slot_from_list (selected, &avail_temp_slots);
833 /* Make our best, if any, the one to use. */
837 cut_slot_from_list (selected, &avail_temp_slots);
839 /* If there are enough aligned bytes left over, make them into a new
840 temp_slot so that the extra bytes don't get wasted. Do this only
841 for BLKmode slots, so that we can be sure of the alignment. */
842 if (GET_MODE (best_p->slot) == BLKmode)
844 int alignment = best_p->align / BITS_PER_UNIT;
845 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
847 if (best_p->size - rounded_size >= alignment)
849 p = ggc_alloc_temp_slot ();
850 p->in_use = p->addr_taken = 0;
851 p->size = best_p->size - rounded_size;
852 p->base_offset = best_p->base_offset + rounded_size;
853 p->full_size = best_p->full_size - rounded_size;
854 p->slot = adjust_address_nv (best_p->slot, BLKmode, rounded_size);
855 p->align = best_p->align;
856 p->type = best_p->type;
857 insert_slot_to_list (p, &avail_temp_slots);
859 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
862 best_p->size = rounded_size;
863 best_p->full_size = rounded_size;
868 /* If we still didn't find one, make a new temporary. */
871 HOST_WIDE_INT frame_offset_old = frame_offset;
873 p = ggc_alloc_temp_slot ();
875 /* We are passing an explicit alignment request to assign_stack_local.
876 One side effect of that is assign_stack_local will not round SIZE
877 to ensure the frame offset remains suitably aligned.
879 So for requests which depended on the rounding of SIZE, we go ahead
880 and round it now. We also make sure ALIGNMENT is at least
881 BIGGEST_ALIGNMENT. */
882 gcc_assert (mode != BLKmode || align == BIGGEST_ALIGNMENT);
883 p->slot = assign_stack_local_1 (mode,
893 /* The following slot size computation is necessary because we don't
894 know the actual size of the temporary slot until assign_stack_local
895 has performed all the frame alignment and size rounding for the
896 requested temporary. Note that extra space added for alignment
897 can be either above or below this stack slot depending on which
898 way the frame grows. We include the extra space if and only if it
899 is above this slot. */
900 if (FRAME_GROWS_DOWNWARD)
901 p->size = frame_offset_old - frame_offset;
905 /* Now define the fields used by combine_temp_slots. */
906 if (FRAME_GROWS_DOWNWARD)
908 p->base_offset = frame_offset;
909 p->full_size = frame_offset_old - frame_offset;
913 p->base_offset = frame_offset_old;
914 p->full_size = frame_offset - frame_offset_old;
924 p->level = temp_slot_level;
927 pp = temp_slots_at_level (p->level);
928 insert_slot_to_list (p, pp);
929 insert_temp_slot_address (XEXP (p->slot, 0), p);
931 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
932 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
933 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list);
935 /* If we know the alias set for the memory that will be used, use
936 it. If there's no TYPE, then we don't know anything about the
937 alias set for the memory. */
938 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
939 set_mem_align (slot, align);
941 /* If a type is specified, set the relevant flags. */
944 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
945 gcc_checking_assert (!MEM_SCALAR_P (slot) && !MEM_IN_STRUCT_P (slot));
946 if (AGGREGATE_TYPE_P (type) || TREE_CODE (type) == COMPLEX_TYPE)
947 MEM_IN_STRUCT_P (slot) = 1;
949 MEM_SCALAR_P (slot) = 1;
951 MEM_NOTRAP_P (slot) = 1;
956 /* Allocate a temporary stack slot and record it for possible later
957 reuse. First three arguments are same as in preceding function. */
960 assign_stack_temp (enum machine_mode mode, HOST_WIDE_INT size, int keep)
962 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
965 /* Assign a temporary.
966 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
967 and so that should be used in error messages. In either case, we
968 allocate of the given type.
969 KEEP is as for assign_stack_temp.
970 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
971 it is 0 if a register is OK.
972 DONT_PROMOTE is 1 if we should not promote values in register
976 assign_temp (tree type_or_decl, int keep, int memory_required,
977 int dont_promote ATTRIBUTE_UNUSED)
980 enum machine_mode mode;
985 if (DECL_P (type_or_decl))
986 decl = type_or_decl, type = TREE_TYPE (decl);
988 decl = NULL, type = type_or_decl;
990 mode = TYPE_MODE (type);
992 unsignedp = TYPE_UNSIGNED (type);
995 if (mode == BLKmode || memory_required)
997 HOST_WIDE_INT size = int_size_in_bytes (type);
1000 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
1001 problems with allocating the stack space. */
1005 /* Unfortunately, we don't yet know how to allocate variable-sized
1006 temporaries. However, sometimes we can find a fixed upper limit on
1007 the size, so try that instead. */
1008 else if (size == -1)
1009 size = max_int_size_in_bytes (type);
1011 /* The size of the temporary may be too large to fit into an integer. */
1012 /* ??? Not sure this should happen except for user silliness, so limit
1013 this to things that aren't compiler-generated temporaries. The
1014 rest of the time we'll die in assign_stack_temp_for_type. */
1015 if (decl && size == -1
1016 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
1018 error ("size of variable %q+D is too large", decl);
1022 tmp = assign_stack_temp_for_type (mode, size, keep, type);
1028 mode = promote_mode (type, mode, &unsignedp);
1031 return gen_reg_rtx (mode);
1034 /* Combine temporary stack slots which are adjacent on the stack.
1036 This allows for better use of already allocated stack space. This is only
1037 done for BLKmode slots because we can be sure that we won't have alignment
1038 problems in this case. */
1041 combine_temp_slots (void)
1043 struct temp_slot *p, *q, *next, *next_q;
1046 /* We can't combine slots, because the information about which slot
1047 is in which alias set will be lost. */
1048 if (flag_strict_aliasing)
1051 /* If there are a lot of temp slots, don't do anything unless
1052 high levels of optimization. */
1053 if (! flag_expensive_optimizations)
1054 for (p = avail_temp_slots, num_slots = 0; p; p = p->next, num_slots++)
1055 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
1058 for (p = avail_temp_slots; p; p = next)
1064 if (GET_MODE (p->slot) != BLKmode)
1067 for (q = p->next; q; q = next_q)
1073 if (GET_MODE (q->slot) != BLKmode)
1076 if (p->base_offset + p->full_size == q->base_offset)
1078 /* Q comes after P; combine Q into P. */
1080 p->full_size += q->full_size;
1083 else if (q->base_offset + q->full_size == p->base_offset)
1085 /* P comes after Q; combine P into Q. */
1087 q->full_size += p->full_size;
1092 cut_slot_from_list (q, &avail_temp_slots);
1095 /* Either delete P or advance past it. */
1097 cut_slot_from_list (p, &avail_temp_slots);
1101 /* Indicate that NEW_RTX is an alternate way of referring to the temp
1102 slot that previously was known by OLD_RTX. */
1105 update_temp_slot_address (rtx old_rtx, rtx new_rtx)
1107 struct temp_slot *p;
1109 if (rtx_equal_p (old_rtx, new_rtx))
1112 p = find_temp_slot_from_address (old_rtx);
1114 /* If we didn't find one, see if both OLD_RTX is a PLUS. If so, and
1115 NEW_RTX is a register, see if one operand of the PLUS is a
1116 temporary location. If so, NEW_RTX points into it. Otherwise,
1117 if both OLD_RTX and NEW_RTX are a PLUS and if there is a register
1118 in common between them. If so, try a recursive call on those
1122 if (GET_CODE (old_rtx) != PLUS)
1125 if (REG_P (new_rtx))
1127 update_temp_slot_address (XEXP (old_rtx, 0), new_rtx);
1128 update_temp_slot_address (XEXP (old_rtx, 1), new_rtx);
1131 else if (GET_CODE (new_rtx) != PLUS)
1134 if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 0)))
1135 update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 1));
1136 else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 0)))
1137 update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 1));
1138 else if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 1)))
1139 update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 0));
1140 else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 1)))
1141 update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 0));
1146 /* Otherwise add an alias for the temp's address. */
1147 insert_temp_slot_address (new_rtx, p);
1150 /* If X could be a reference to a temporary slot, mark the fact that its
1151 address was taken. */
1154 mark_temp_addr_taken (rtx x)
1156 struct temp_slot *p;
1161 /* If X is not in memory or is at a constant address, it cannot be in
1162 a temporary slot. */
1163 if (!MEM_P (x) || CONSTANT_P (XEXP (x, 0)))
1166 p = find_temp_slot_from_address (XEXP (x, 0));
1171 /* If X could be a reference to a temporary slot, mark that slot as
1172 belonging to the to one level higher than the current level. If X
1173 matched one of our slots, just mark that one. Otherwise, we can't
1174 easily predict which it is, so upgrade all of them. Kept slots
1175 need not be touched.
1177 This is called when an ({...}) construct occurs and a statement
1178 returns a value in memory. */
1181 preserve_temp_slots (rtx x)
1183 struct temp_slot *p = 0, *next;
1185 /* If there is no result, we still might have some objects whose address
1186 were taken, so we need to make sure they stay around. */
1189 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1194 move_slot_to_level (p, temp_slot_level - 1);
1200 /* If X is a register that is being used as a pointer, see if we have
1201 a temporary slot we know it points to. To be consistent with
1202 the code below, we really should preserve all non-kept slots
1203 if we can't find a match, but that seems to be much too costly. */
1204 if (REG_P (x) && REG_POINTER (x))
1205 p = find_temp_slot_from_address (x);
1207 /* If X is not in memory or is at a constant address, it cannot be in
1208 a temporary slot, but it can contain something whose address was
1210 if (p == 0 && (!MEM_P (x) || CONSTANT_P (XEXP (x, 0))))
1212 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1217 move_slot_to_level (p, temp_slot_level - 1);
1223 /* First see if we can find a match. */
1225 p = find_temp_slot_from_address (XEXP (x, 0));
1229 /* Move everything at our level whose address was taken to our new
1230 level in case we used its address. */
1231 struct temp_slot *q;
1233 if (p->level == temp_slot_level)
1235 for (q = *temp_slots_at_level (temp_slot_level); q; q = next)
1239 if (p != q && q->addr_taken)
1240 move_slot_to_level (q, temp_slot_level - 1);
1243 move_slot_to_level (p, temp_slot_level - 1);
1249 /* Otherwise, preserve all non-kept slots at this level. */
1250 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1255 move_slot_to_level (p, temp_slot_level - 1);
1259 /* Free all temporaries used so far. This is normally called at the
1260 end of generating code for a statement. */
1263 free_temp_slots (void)
1265 struct temp_slot *p, *next;
1266 bool some_available = false;
1268 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1274 make_slot_available (p);
1275 some_available = true;
1281 remove_unused_temp_slot_addresses ();
1282 combine_temp_slots ();
1286 /* Push deeper into the nesting level for stack temporaries. */
1289 push_temp_slots (void)
1294 /* Pop a temporary nesting level. All slots in use in the current level
1298 pop_temp_slots (void)
1300 struct temp_slot *p, *next;
1301 bool some_available = false;
1303 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1306 make_slot_available (p);
1307 some_available = true;
1312 remove_unused_temp_slot_addresses ();
1313 combine_temp_slots ();
1319 /* Initialize temporary slots. */
1322 init_temp_slots (void)
1324 /* We have not allocated any temporaries yet. */
1325 avail_temp_slots = 0;
1326 used_temp_slots = 0;
1327 temp_slot_level = 0;
1329 /* Set up the table to map addresses to temp slots. */
1330 if (! temp_slot_address_table)
1331 temp_slot_address_table = htab_create_ggc (32,
1332 temp_slot_address_hash,
1333 temp_slot_address_eq,
1336 htab_empty (temp_slot_address_table);
1339 /* These routines are responsible for converting virtual register references
1340 to the actual hard register references once RTL generation is complete.
1342 The following four variables are used for communication between the
1343 routines. They contain the offsets of the virtual registers from their
1344 respective hard registers. */
1346 static int in_arg_offset;
1347 static int var_offset;
1348 static int dynamic_offset;
1349 static int out_arg_offset;
1350 static int cfa_offset;
1352 /* In most machines, the stack pointer register is equivalent to the bottom
1355 #ifndef STACK_POINTER_OFFSET
1356 #define STACK_POINTER_OFFSET 0
1359 /* If not defined, pick an appropriate default for the offset of dynamically
1360 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1361 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1363 #ifndef STACK_DYNAMIC_OFFSET
1365 /* The bottom of the stack points to the actual arguments. If
1366 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1367 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1368 stack space for register parameters is not pushed by the caller, but
1369 rather part of the fixed stack areas and hence not included in
1370 `crtl->outgoing_args_size'. Nevertheless, we must allow
1371 for it when allocating stack dynamic objects. */
1373 #if defined(REG_PARM_STACK_SPACE)
1374 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1375 ((ACCUMULATE_OUTGOING_ARGS \
1376 ? (crtl->outgoing_args_size \
1377 + (OUTGOING_REG_PARM_STACK_SPACE ((!(FNDECL) ? NULL_TREE : TREE_TYPE (FNDECL))) ? 0 \
1378 : REG_PARM_STACK_SPACE (FNDECL))) \
1379 : 0) + (STACK_POINTER_OFFSET))
1381 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1382 ((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : 0) \
1383 + (STACK_POINTER_OFFSET))
1388 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1389 is a virtual register, return the equivalent hard register and set the
1390 offset indirectly through the pointer. Otherwise, return 0. */
1393 instantiate_new_reg (rtx x, HOST_WIDE_INT *poffset)
1396 HOST_WIDE_INT offset;
1398 if (x == virtual_incoming_args_rtx)
1400 if (stack_realign_drap)
1402 /* Replace virtual_incoming_args_rtx with internal arg
1403 pointer if DRAP is used to realign stack. */
1404 new_rtx = crtl->args.internal_arg_pointer;
1408 new_rtx = arg_pointer_rtx, offset = in_arg_offset;
1410 else if (x == virtual_stack_vars_rtx)
1411 new_rtx = frame_pointer_rtx, offset = var_offset;
1412 else if (x == virtual_stack_dynamic_rtx)
1413 new_rtx = stack_pointer_rtx, offset = dynamic_offset;
1414 else if (x == virtual_outgoing_args_rtx)
1415 new_rtx = stack_pointer_rtx, offset = out_arg_offset;
1416 else if (x == virtual_cfa_rtx)
1418 #ifdef FRAME_POINTER_CFA_OFFSET
1419 new_rtx = frame_pointer_rtx;
1421 new_rtx = arg_pointer_rtx;
1423 offset = cfa_offset;
1425 else if (x == virtual_preferred_stack_boundary_rtx)
1427 new_rtx = GEN_INT (crtl->preferred_stack_boundary / BITS_PER_UNIT);
1437 /* A subroutine of instantiate_virtual_regs, called via for_each_rtx.
1438 Instantiate any virtual registers present inside of *LOC. The expression
1439 is simplified, as much as possible, but is not to be considered "valid"
1440 in any sense implied by the target. If any change is made, set CHANGED
1444 instantiate_virtual_regs_in_rtx (rtx *loc, void *data)
1446 HOST_WIDE_INT offset;
1447 bool *changed = (bool *) data;
1454 switch (GET_CODE (x))
1457 new_rtx = instantiate_new_reg (x, &offset);
1460 *loc = plus_constant (new_rtx, offset);
1467 new_rtx = instantiate_new_reg (XEXP (x, 0), &offset);
1470 new_rtx = plus_constant (new_rtx, offset);
1471 *loc = simplify_gen_binary (PLUS, GET_MODE (x), new_rtx, XEXP (x, 1));
1477 /* FIXME -- from old code */
1478 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1479 we can commute the PLUS and SUBREG because pointers into the
1480 frame are well-behaved. */
1490 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1491 matches the predicate for insn CODE operand OPERAND. */
1494 safe_insn_predicate (int code, int operand, rtx x)
1496 return code < 0 || insn_operand_matches ((enum insn_code) code, operand, x);
1499 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1500 registers present inside of insn. The result will be a valid insn. */
1503 instantiate_virtual_regs_in_insn (rtx insn)
1505 HOST_WIDE_INT offset;
1507 bool any_change = false;
1508 rtx set, new_rtx, x, seq;
1510 /* There are some special cases to be handled first. */
1511 set = single_set (insn);
1514 /* We're allowed to assign to a virtual register. This is interpreted
1515 to mean that the underlying register gets assigned the inverse
1516 transformation. This is used, for example, in the handling of
1518 new_rtx = instantiate_new_reg (SET_DEST (set), &offset);
1523 for_each_rtx (&SET_SRC (set), instantiate_virtual_regs_in_rtx, NULL);
1524 x = simplify_gen_binary (PLUS, GET_MODE (new_rtx), SET_SRC (set),
1526 x = force_operand (x, new_rtx);
1528 emit_move_insn (new_rtx, x);
1533 emit_insn_before (seq, insn);
1538 /* Handle a straight copy from a virtual register by generating a
1539 new add insn. The difference between this and falling through
1540 to the generic case is avoiding a new pseudo and eliminating a
1541 move insn in the initial rtl stream. */
1542 new_rtx = instantiate_new_reg (SET_SRC (set), &offset);
1543 if (new_rtx && offset != 0
1544 && REG_P (SET_DEST (set))
1545 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1549 x = expand_simple_binop (GET_MODE (SET_DEST (set)), PLUS,
1550 new_rtx, GEN_INT (offset), SET_DEST (set),
1551 1, OPTAB_LIB_WIDEN);
1552 if (x != SET_DEST (set))
1553 emit_move_insn (SET_DEST (set), x);
1558 emit_insn_before (seq, insn);
1563 extract_insn (insn);
1564 insn_code = INSN_CODE (insn);
1566 /* Handle a plus involving a virtual register by determining if the
1567 operands remain valid if they're modified in place. */
1568 if (GET_CODE (SET_SRC (set)) == PLUS
1569 && recog_data.n_operands >= 3
1570 && recog_data.operand_loc[1] == &XEXP (SET_SRC (set), 0)
1571 && recog_data.operand_loc[2] == &XEXP (SET_SRC (set), 1)
1572 && CONST_INT_P (recog_data.operand[2])
1573 && (new_rtx = instantiate_new_reg (recog_data.operand[1], &offset)))
1575 offset += INTVAL (recog_data.operand[2]);
1577 /* If the sum is zero, then replace with a plain move. */
1579 && REG_P (SET_DEST (set))
1580 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1583 emit_move_insn (SET_DEST (set), new_rtx);
1587 emit_insn_before (seq, insn);
1592 x = gen_int_mode (offset, recog_data.operand_mode[2]);
1594 /* Using validate_change and apply_change_group here leaves
1595 recog_data in an invalid state. Since we know exactly what
1596 we want to check, do those two by hand. */
1597 if (safe_insn_predicate (insn_code, 1, new_rtx)
1598 && safe_insn_predicate (insn_code, 2, x))
1600 *recog_data.operand_loc[1] = recog_data.operand[1] = new_rtx;
1601 *recog_data.operand_loc[2] = recog_data.operand[2] = x;
1604 /* Fall through into the regular operand fixup loop in
1605 order to take care of operands other than 1 and 2. */
1611 extract_insn (insn);
1612 insn_code = INSN_CODE (insn);
1615 /* In the general case, we expect virtual registers to appear only in
1616 operands, and then only as either bare registers or inside memories. */
1617 for (i = 0; i < recog_data.n_operands; ++i)
1619 x = recog_data.operand[i];
1620 switch (GET_CODE (x))
1624 rtx addr = XEXP (x, 0);
1625 bool changed = false;
1627 for_each_rtx (&addr, instantiate_virtual_regs_in_rtx, &changed);
1632 x = replace_equiv_address (x, addr);
1633 /* It may happen that the address with the virtual reg
1634 was valid (e.g. based on the virtual stack reg, which might
1635 be acceptable to the predicates with all offsets), whereas
1636 the address now isn't anymore, for instance when the address
1637 is still offsetted, but the base reg isn't virtual-stack-reg
1638 anymore. Below we would do a force_reg on the whole operand,
1639 but this insn might actually only accept memory. Hence,
1640 before doing that last resort, try to reload the address into
1641 a register, so this operand stays a MEM. */
1642 if (!safe_insn_predicate (insn_code, i, x))
1644 addr = force_reg (GET_MODE (addr), addr);
1645 x = replace_equiv_address (x, addr);
1650 emit_insn_before (seq, insn);
1655 new_rtx = instantiate_new_reg (x, &offset);
1656 if (new_rtx == NULL)
1664 /* Careful, special mode predicates may have stuff in
1665 insn_data[insn_code].operand[i].mode that isn't useful
1666 to us for computing a new value. */
1667 /* ??? Recognize address_operand and/or "p" constraints
1668 to see if (plus new offset) is a valid before we put
1669 this through expand_simple_binop. */
1670 x = expand_simple_binop (GET_MODE (x), PLUS, new_rtx,
1671 GEN_INT (offset), NULL_RTX,
1672 1, OPTAB_LIB_WIDEN);
1675 emit_insn_before (seq, insn);
1680 new_rtx = instantiate_new_reg (SUBREG_REG (x), &offset);
1681 if (new_rtx == NULL)
1686 new_rtx = expand_simple_binop (GET_MODE (new_rtx), PLUS, new_rtx,
1687 GEN_INT (offset), NULL_RTX,
1688 1, OPTAB_LIB_WIDEN);
1691 emit_insn_before (seq, insn);
1693 x = simplify_gen_subreg (recog_data.operand_mode[i], new_rtx,
1694 GET_MODE (new_rtx), SUBREG_BYTE (x));
1702 /* At this point, X contains the new value for the operand.
1703 Validate the new value vs the insn predicate. Note that
1704 asm insns will have insn_code -1 here. */
1705 if (!safe_insn_predicate (insn_code, i, x))
1710 gcc_assert (REGNO (x) <= LAST_VIRTUAL_REGISTER);
1711 x = copy_to_reg (x);
1714 x = force_reg (insn_data[insn_code].operand[i].mode, x);
1718 emit_insn_before (seq, insn);
1721 *recog_data.operand_loc[i] = recog_data.operand[i] = x;
1727 /* Propagate operand changes into the duplicates. */
1728 for (i = 0; i < recog_data.n_dups; ++i)
1729 *recog_data.dup_loc[i]
1730 = copy_rtx (recog_data.operand[(unsigned)recog_data.dup_num[i]]);
1732 /* Force re-recognition of the instruction for validation. */
1733 INSN_CODE (insn) = -1;
1736 if (asm_noperands (PATTERN (insn)) >= 0)
1738 if (!check_asm_operands (PATTERN (insn)))
1740 error_for_asm (insn, "impossible constraint in %<asm%>");
1746 if (recog_memoized (insn) < 0)
1747 fatal_insn_not_found (insn);
1751 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1752 do any instantiation required. */
1755 instantiate_decl_rtl (rtx x)
1762 /* If this is a CONCAT, recurse for the pieces. */
1763 if (GET_CODE (x) == CONCAT)
1765 instantiate_decl_rtl (XEXP (x, 0));
1766 instantiate_decl_rtl (XEXP (x, 1));
1770 /* If this is not a MEM, no need to do anything. Similarly if the
1771 address is a constant or a register that is not a virtual register. */
1776 if (CONSTANT_P (addr)
1778 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
1779 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
1782 for_each_rtx (&XEXP (x, 0), instantiate_virtual_regs_in_rtx, NULL);
1785 /* Helper for instantiate_decls called via walk_tree: Process all decls
1786 in the given DECL_VALUE_EXPR. */
1789 instantiate_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
1797 if (DECL_RTL_SET_P (t))
1798 instantiate_decl_rtl (DECL_RTL (t));
1799 if (TREE_CODE (t) == PARM_DECL && DECL_NAMELESS (t)
1800 && DECL_INCOMING_RTL (t))
1801 instantiate_decl_rtl (DECL_INCOMING_RTL (t));
1802 if ((TREE_CODE (t) == VAR_DECL
1803 || TREE_CODE (t) == RESULT_DECL)
1804 && DECL_HAS_VALUE_EXPR_P (t))
1806 tree v = DECL_VALUE_EXPR (t);
1807 walk_tree (&v, instantiate_expr, NULL, NULL);
1814 /* Subroutine of instantiate_decls: Process all decls in the given
1815 BLOCK node and all its subblocks. */
1818 instantiate_decls_1 (tree let)
1822 for (t = BLOCK_VARS (let); t; t = DECL_CHAIN (t))
1824 if (DECL_RTL_SET_P (t))
1825 instantiate_decl_rtl (DECL_RTL (t));
1826 if (TREE_CODE (t) == VAR_DECL && DECL_HAS_VALUE_EXPR_P (t))
1828 tree v = DECL_VALUE_EXPR (t);
1829 walk_tree (&v, instantiate_expr, NULL, NULL);
1833 /* Process all subblocks. */
1834 for (t = BLOCK_SUBBLOCKS (let); t; t = BLOCK_CHAIN (t))
1835 instantiate_decls_1 (t);
1838 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1839 all virtual registers in their DECL_RTL's. */
1842 instantiate_decls (tree fndecl)
1847 /* Process all parameters of the function. */
1848 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = DECL_CHAIN (decl))
1850 instantiate_decl_rtl (DECL_RTL (decl));
1851 instantiate_decl_rtl (DECL_INCOMING_RTL (decl));
1852 if (DECL_HAS_VALUE_EXPR_P (decl))
1854 tree v = DECL_VALUE_EXPR (decl);
1855 walk_tree (&v, instantiate_expr, NULL, NULL);
1859 if ((decl = DECL_RESULT (fndecl))
1860 && TREE_CODE (decl) == RESULT_DECL)
1862 if (DECL_RTL_SET_P (decl))
1863 instantiate_decl_rtl (DECL_RTL (decl));
1864 if (DECL_HAS_VALUE_EXPR_P (decl))
1866 tree v = DECL_VALUE_EXPR (decl);
1867 walk_tree (&v, instantiate_expr, NULL, NULL);
1871 /* Now process all variables defined in the function or its subblocks. */
1872 instantiate_decls_1 (DECL_INITIAL (fndecl));
1874 FOR_EACH_LOCAL_DECL (cfun, ix, decl)
1875 if (DECL_RTL_SET_P (decl))
1876 instantiate_decl_rtl (DECL_RTL (decl));
1877 VEC_free (tree, gc, cfun->local_decls);
1880 /* Pass through the INSNS of function FNDECL and convert virtual register
1881 references to hard register references. */
1884 instantiate_virtual_regs (void)
1888 /* Compute the offsets to use for this function. */
1889 in_arg_offset = FIRST_PARM_OFFSET (current_function_decl);
1890 var_offset = STARTING_FRAME_OFFSET;
1891 dynamic_offset = STACK_DYNAMIC_OFFSET (current_function_decl);
1892 out_arg_offset = STACK_POINTER_OFFSET;
1893 #ifdef FRAME_POINTER_CFA_OFFSET
1894 cfa_offset = FRAME_POINTER_CFA_OFFSET (current_function_decl);
1896 cfa_offset = ARG_POINTER_CFA_OFFSET (current_function_decl);
1899 /* Initialize recognition, indicating that volatile is OK. */
1902 /* Scan through all the insns, instantiating every virtual register still
1908 FOR_BB_INSNS_SAFE (bb, insn, curr)
1912 /* These patterns in the instruction stream can never be recognized.
1913 Fortunately, they shouldn't contain virtual registers either. */
1914 if (GET_CODE (PATTERN (insn)) == USE
1915 || GET_CODE (PATTERN (insn)) == CLOBBER
1916 || GET_CODE (PATTERN (insn)) == ADDR_VEC
1917 || GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC
1918 || GET_CODE (PATTERN (insn)) == ASM_INPUT)
1920 else if (DEBUG_INSN_P (insn))
1921 for_each_rtx (&INSN_VAR_LOCATION (insn),
1922 instantiate_virtual_regs_in_rtx, NULL);
1924 instantiate_virtual_regs_in_insn (insn);
1926 if (INSN_DELETED_P (insn))
1929 for_each_rtx (®_NOTES (insn), instantiate_virtual_regs_in_rtx, NULL);
1931 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1933 for_each_rtx (&CALL_INSN_FUNCTION_USAGE (insn),
1934 instantiate_virtual_regs_in_rtx, NULL);
1939 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1940 instantiate_decls (current_function_decl);
1942 targetm.instantiate_decls ();
1944 /* Indicate that, from now on, assign_stack_local should use
1945 frame_pointer_rtx. */
1946 virtuals_instantiated = 1;
1948 /* See allocate_dynamic_stack_space for the rationale. */
1949 #ifdef SETJMP_VIA_SAVE_AREA
1950 if (flag_stack_usage && cfun->calls_setjmp)
1952 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
1953 dynamic_offset = (dynamic_offset + align - 1) / align * align;
1954 current_function_dynamic_stack_size
1955 += current_function_dynamic_alloc_count * dynamic_offset;
1962 struct rtl_opt_pass pass_instantiate_virtual_regs =
1968 instantiate_virtual_regs, /* execute */
1971 0, /* static_pass_number */
1972 TV_NONE, /* tv_id */
1973 PROP_cfglayout, /* properties_required */
1974 0, /* properties_provided */
1975 0, /* properties_destroyed */
1976 0, /* todo_flags_start */
1977 TODO_dump_func /* todo_flags_finish */
1982 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
1983 This means a type for which function calls must pass an address to the
1984 function or get an address back from the function.
1985 EXP may be a type node or an expression (whose type is tested). */
1988 aggregate_value_p (const_tree exp, const_tree fntype)
1990 const_tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
1991 int i, regno, nregs;
1995 switch (TREE_CODE (fntype))
1999 tree fndecl = get_callee_fndecl (fntype);
2001 ? TREE_TYPE (fndecl)
2002 : TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (fntype))));
2006 fntype = TREE_TYPE (fntype);
2011 case IDENTIFIER_NODE:
2015 /* We don't expect other tree types here. */
2019 if (VOID_TYPE_P (type))
2022 /* If a record should be passed the same as its first (and only) member
2023 don't pass it as an aggregate. */
2024 if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
2025 return aggregate_value_p (first_field (type), fntype);
2027 /* If the front end has decided that this needs to be passed by
2028 reference, do so. */
2029 if ((TREE_CODE (exp) == PARM_DECL || TREE_CODE (exp) == RESULT_DECL)
2030 && DECL_BY_REFERENCE (exp))
2033 /* Function types that are TREE_ADDRESSABLE force return in memory. */
2034 if (fntype && TREE_ADDRESSABLE (fntype))
2037 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
2038 and thus can't be returned in registers. */
2039 if (TREE_ADDRESSABLE (type))
2042 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
2045 if (targetm.calls.return_in_memory (type, fntype))
2048 /* Make sure we have suitable call-clobbered regs to return
2049 the value in; if not, we must return it in memory. */
2050 reg = hard_function_value (type, 0, fntype, 0);
2052 /* If we have something other than a REG (e.g. a PARALLEL), then assume
2057 regno = REGNO (reg);
2058 nregs = hard_regno_nregs[regno][TYPE_MODE (type)];
2059 for (i = 0; i < nregs; i++)
2060 if (! call_used_regs[regno + i])
2066 /* Return true if we should assign DECL a pseudo register; false if it
2067 should live on the local stack. */
2070 use_register_for_decl (const_tree decl)
2072 if (!targetm.calls.allocate_stack_slots_for_args())
2075 /* Honor volatile. */
2076 if (TREE_SIDE_EFFECTS (decl))
2079 /* Honor addressability. */
2080 if (TREE_ADDRESSABLE (decl))
2083 /* Only register-like things go in registers. */
2084 if (DECL_MODE (decl) == BLKmode)
2087 /* If -ffloat-store specified, don't put explicit float variables
2089 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
2090 propagates values across these stores, and it probably shouldn't. */
2091 if (flag_float_store && FLOAT_TYPE_P (TREE_TYPE (decl)))
2094 /* If we're not interested in tracking debugging information for
2095 this decl, then we can certainly put it in a register. */
2096 if (DECL_IGNORED_P (decl))
2102 if (!DECL_REGISTER (decl))
2105 switch (TREE_CODE (TREE_TYPE (decl)))
2109 case QUAL_UNION_TYPE:
2110 /* When not optimizing, disregard register keyword for variables with
2111 types containing methods, otherwise the methods won't be callable
2112 from the debugger. */
2113 if (TYPE_METHODS (TREE_TYPE (decl)))
2123 /* Return true if TYPE should be passed by invisible reference. */
2126 pass_by_reference (CUMULATIVE_ARGS *ca, enum machine_mode mode,
2127 tree type, bool named_arg)
2131 /* If this type contains non-trivial constructors, then it is
2132 forbidden for the middle-end to create any new copies. */
2133 if (TREE_ADDRESSABLE (type))
2136 /* GCC post 3.4 passes *all* variable sized types by reference. */
2137 if (!TYPE_SIZE (type) || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
2140 /* If a record type should be passed the same as its first (and only)
2141 member, use the type and mode of that member. */
2142 if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
2144 type = TREE_TYPE (first_field (type));
2145 mode = TYPE_MODE (type);
2149 return targetm.calls.pass_by_reference (ca, mode, type, named_arg);
2152 /* Return true if TYPE, which is passed by reference, should be callee
2153 copied instead of caller copied. */
2156 reference_callee_copied (CUMULATIVE_ARGS *ca, enum machine_mode mode,
2157 tree type, bool named_arg)
2159 if (type && TREE_ADDRESSABLE (type))
2161 return targetm.calls.callee_copies (ca, mode, type, named_arg);
2164 /* Structures to communicate between the subroutines of assign_parms.
2165 The first holds data persistent across all parameters, the second
2166 is cleared out for each parameter. */
2168 struct assign_parm_data_all
2170 CUMULATIVE_ARGS args_so_far;
2171 struct args_size stack_args_size;
2172 tree function_result_decl;
2174 rtx first_conversion_insn;
2175 rtx last_conversion_insn;
2176 HOST_WIDE_INT pretend_args_size;
2177 HOST_WIDE_INT extra_pretend_bytes;
2178 int reg_parm_stack_space;
2181 struct assign_parm_data_one
2187 enum machine_mode nominal_mode;
2188 enum machine_mode passed_mode;
2189 enum machine_mode promoted_mode;
2190 struct locate_and_pad_arg_data locate;
2192 BOOL_BITFIELD named_arg : 1;
2193 BOOL_BITFIELD passed_pointer : 1;
2194 BOOL_BITFIELD on_stack : 1;
2195 BOOL_BITFIELD loaded_in_reg : 1;
2198 /* A subroutine of assign_parms. Initialize ALL. */
2201 assign_parms_initialize_all (struct assign_parm_data_all *all)
2203 tree fntype ATTRIBUTE_UNUSED;
2205 memset (all, 0, sizeof (*all));
2207 fntype = TREE_TYPE (current_function_decl);
2209 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
2210 INIT_CUMULATIVE_INCOMING_ARGS (all->args_so_far, fntype, NULL_RTX);
2212 INIT_CUMULATIVE_ARGS (all->args_so_far, fntype, NULL_RTX,
2213 current_function_decl, -1);
2216 #ifdef REG_PARM_STACK_SPACE
2217 all->reg_parm_stack_space = REG_PARM_STACK_SPACE (current_function_decl);
2221 /* If ARGS contains entries with complex types, split the entry into two
2222 entries of the component type. Return a new list of substitutions are
2223 needed, else the old list. */
2226 split_complex_args (VEC(tree, heap) **args)
2231 FOR_EACH_VEC_ELT (tree, *args, i, p)
2233 tree type = TREE_TYPE (p);
2234 if (TREE_CODE (type) == COMPLEX_TYPE
2235 && targetm.calls.split_complex_arg (type))
2238 tree subtype = TREE_TYPE (type);
2239 bool addressable = TREE_ADDRESSABLE (p);
2241 /* Rewrite the PARM_DECL's type with its component. */
2243 TREE_TYPE (p) = subtype;
2244 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
2245 DECL_MODE (p) = VOIDmode;
2246 DECL_SIZE (p) = NULL;
2247 DECL_SIZE_UNIT (p) = NULL;
2248 /* If this arg must go in memory, put it in a pseudo here.
2249 We can't allow it to go in memory as per normal parms,
2250 because the usual place might not have the imag part
2251 adjacent to the real part. */
2252 DECL_ARTIFICIAL (p) = addressable;
2253 DECL_IGNORED_P (p) = addressable;
2254 TREE_ADDRESSABLE (p) = 0;
2256 VEC_replace (tree, *args, i, p);
2258 /* Build a second synthetic decl. */
2259 decl = build_decl (EXPR_LOCATION (p),
2260 PARM_DECL, NULL_TREE, subtype);
2261 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
2262 DECL_ARTIFICIAL (decl) = addressable;
2263 DECL_IGNORED_P (decl) = addressable;
2264 layout_decl (decl, 0);
2265 VEC_safe_insert (tree, heap, *args, ++i, decl);
2270 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
2271 the hidden struct return argument, and (abi willing) complex args.
2272 Return the new parameter list. */
2274 static VEC(tree, heap) *
2275 assign_parms_augmented_arg_list (struct assign_parm_data_all *all)
2277 tree fndecl = current_function_decl;
2278 tree fntype = TREE_TYPE (fndecl);
2279 VEC(tree, heap) *fnargs = NULL;
2282 for (arg = DECL_ARGUMENTS (fndecl); arg; arg = DECL_CHAIN (arg))
2283 VEC_safe_push (tree, heap, fnargs, arg);
2285 all->orig_fnargs = DECL_ARGUMENTS (fndecl);
2287 /* If struct value address is treated as the first argument, make it so. */
2288 if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
2289 && ! cfun->returns_pcc_struct
2290 && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
2292 tree type = build_pointer_type (TREE_TYPE (fntype));
2295 decl = build_decl (DECL_SOURCE_LOCATION (fndecl),
2296 PARM_DECL, get_identifier (".result_ptr"), type);
2297 DECL_ARG_TYPE (decl) = type;
2298 DECL_ARTIFICIAL (decl) = 1;
2299 DECL_NAMELESS (decl) = 1;
2300 TREE_CONSTANT (decl) = 1;
2302 DECL_CHAIN (decl) = all->orig_fnargs;
2303 all->orig_fnargs = decl;
2304 VEC_safe_insert (tree, heap, fnargs, 0, decl);
2306 all->function_result_decl = decl;
2309 /* If the target wants to split complex arguments into scalars, do so. */
2310 if (targetm.calls.split_complex_arg)
2311 split_complex_args (&fnargs);
2316 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2317 data for the parameter. Incorporate ABI specifics such as pass-by-
2318 reference and type promotion. */
2321 assign_parm_find_data_types (struct assign_parm_data_all *all, tree parm,
2322 struct assign_parm_data_one *data)
2324 tree nominal_type, passed_type;
2325 enum machine_mode nominal_mode, passed_mode, promoted_mode;
2328 memset (data, 0, sizeof (*data));
2330 /* NAMED_ARG is a misnomer. We really mean 'non-variadic'. */
2332 data->named_arg = 1; /* No variadic parms. */
2333 else if (DECL_CHAIN (parm))
2334 data->named_arg = 1; /* Not the last non-variadic parm. */
2335 else if (targetm.calls.strict_argument_naming (&all->args_so_far))
2336 data->named_arg = 1; /* Only variadic ones are unnamed. */
2338 data->named_arg = 0; /* Treat as variadic. */
2340 nominal_type = TREE_TYPE (parm);
2341 passed_type = DECL_ARG_TYPE (parm);
2343 /* Look out for errors propagating this far. Also, if the parameter's
2344 type is void then its value doesn't matter. */
2345 if (TREE_TYPE (parm) == error_mark_node
2346 /* This can happen after weird syntax errors
2347 or if an enum type is defined among the parms. */
2348 || TREE_CODE (parm) != PARM_DECL
2349 || passed_type == NULL
2350 || VOID_TYPE_P (nominal_type))
2352 nominal_type = passed_type = void_type_node;
2353 nominal_mode = passed_mode = promoted_mode = VOIDmode;
2357 /* Find mode of arg as it is passed, and mode of arg as it should be
2358 during execution of this function. */
2359 passed_mode = TYPE_MODE (passed_type);
2360 nominal_mode = TYPE_MODE (nominal_type);
2362 /* If the parm is to be passed as a transparent union or record, use the
2363 type of the first field for the tests below. We have already verified
2364 that the modes are the same. */
2365 if ((TREE_CODE (passed_type) == UNION_TYPE
2366 || TREE_CODE (passed_type) == RECORD_TYPE)
2367 && TYPE_TRANSPARENT_AGGR (passed_type))
2368 passed_type = TREE_TYPE (first_field (passed_type));
2370 /* See if this arg was passed by invisible reference. */
2371 if (pass_by_reference (&all->args_so_far, passed_mode,
2372 passed_type, data->named_arg))
2374 passed_type = nominal_type = build_pointer_type (passed_type);
2375 data->passed_pointer = true;
2376 passed_mode = nominal_mode = Pmode;
2379 /* Find mode as it is passed by the ABI. */
2380 unsignedp = TYPE_UNSIGNED (passed_type);
2381 promoted_mode = promote_function_mode (passed_type, passed_mode, &unsignedp,
2382 TREE_TYPE (current_function_decl), 0);
2385 data->nominal_type = nominal_type;
2386 data->passed_type = passed_type;
2387 data->nominal_mode = nominal_mode;
2388 data->passed_mode = passed_mode;
2389 data->promoted_mode = promoted_mode;
2392 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2395 assign_parms_setup_varargs (struct assign_parm_data_all *all,
2396 struct assign_parm_data_one *data, bool no_rtl)
2398 int varargs_pretend_bytes = 0;
2400 targetm.calls.setup_incoming_varargs (&all->args_so_far,
2401 data->promoted_mode,
2403 &varargs_pretend_bytes, no_rtl);
2405 /* If the back-end has requested extra stack space, record how much is
2406 needed. Do not change pretend_args_size otherwise since it may be
2407 nonzero from an earlier partial argument. */
2408 if (varargs_pretend_bytes > 0)
2409 all->pretend_args_size = varargs_pretend_bytes;
2412 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2413 the incoming location of the current parameter. */
2416 assign_parm_find_entry_rtl (struct assign_parm_data_all *all,
2417 struct assign_parm_data_one *data)
2419 HOST_WIDE_INT pretend_bytes = 0;
2423 if (data->promoted_mode == VOIDmode)
2425 data->entry_parm = data->stack_parm = const0_rtx;
2429 entry_parm = targetm.calls.function_incoming_arg (&all->args_so_far,
2430 data->promoted_mode,
2434 if (entry_parm == 0)
2435 data->promoted_mode = data->passed_mode;
2437 /* Determine parm's home in the stack, in case it arrives in the stack
2438 or we should pretend it did. Compute the stack position and rtx where
2439 the argument arrives and its size.
2441 There is one complexity here: If this was a parameter that would
2442 have been passed in registers, but wasn't only because it is
2443 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2444 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2445 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2446 as it was the previous time. */
2447 in_regs = entry_parm != 0;
2448 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2451 if (!in_regs && !data->named_arg)
2453 if (targetm.calls.pretend_outgoing_varargs_named (&all->args_so_far))
2456 tem = targetm.calls.function_incoming_arg (&all->args_so_far,
2457 data->promoted_mode,
2458 data->passed_type, true);
2459 in_regs = tem != NULL;
2463 /* If this parameter was passed both in registers and in the stack, use
2464 the copy on the stack. */
2465 if (targetm.calls.must_pass_in_stack (data->promoted_mode,
2473 partial = targetm.calls.arg_partial_bytes (&all->args_so_far,
2474 data->promoted_mode,
2477 data->partial = partial;
2479 /* The caller might already have allocated stack space for the
2480 register parameters. */
2481 if (partial != 0 && all->reg_parm_stack_space == 0)
2483 /* Part of this argument is passed in registers and part
2484 is passed on the stack. Ask the prologue code to extend
2485 the stack part so that we can recreate the full value.
2487 PRETEND_BYTES is the size of the registers we need to store.
2488 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2489 stack space that the prologue should allocate.
2491 Internally, gcc assumes that the argument pointer is aligned
2492 to STACK_BOUNDARY bits. This is used both for alignment
2493 optimizations (see init_emit) and to locate arguments that are
2494 aligned to more than PARM_BOUNDARY bits. We must preserve this
2495 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2496 a stack boundary. */
2498 /* We assume at most one partial arg, and it must be the first
2499 argument on the stack. */
2500 gcc_assert (!all->extra_pretend_bytes && !all->pretend_args_size);
2502 pretend_bytes = partial;
2503 all->pretend_args_size = CEIL_ROUND (pretend_bytes, STACK_BYTES);
2505 /* We want to align relative to the actual stack pointer, so
2506 don't include this in the stack size until later. */
2507 all->extra_pretend_bytes = all->pretend_args_size;
2511 locate_and_pad_parm (data->promoted_mode, data->passed_type, in_regs,
2512 entry_parm ? data->partial : 0, current_function_decl,
2513 &all->stack_args_size, &data->locate);
2515 /* Update parm_stack_boundary if this parameter is passed in the
2517 if (!in_regs && crtl->parm_stack_boundary < data->locate.boundary)
2518 crtl->parm_stack_boundary = data->locate.boundary;
2520 /* Adjust offsets to include the pretend args. */
2521 pretend_bytes = all->extra_pretend_bytes - pretend_bytes;
2522 data->locate.slot_offset.constant += pretend_bytes;
2523 data->locate.offset.constant += pretend_bytes;
2525 data->entry_parm = entry_parm;
2528 /* A subroutine of assign_parms. If there is actually space on the stack
2529 for this parm, count it in stack_args_size and return true. */
2532 assign_parm_is_stack_parm (struct assign_parm_data_all *all,
2533 struct assign_parm_data_one *data)
2535 /* Trivially true if we've no incoming register. */
2536 if (data->entry_parm == NULL)
2538 /* Also true if we're partially in registers and partially not,
2539 since we've arranged to drop the entire argument on the stack. */
2540 else if (data->partial != 0)
2542 /* Also true if the target says that it's passed in both registers
2543 and on the stack. */
2544 else if (GET_CODE (data->entry_parm) == PARALLEL
2545 && XEXP (XVECEXP (data->entry_parm, 0, 0), 0) == NULL_RTX)
2547 /* Also true if the target says that there's stack allocated for
2548 all register parameters. */
2549 else if (all->reg_parm_stack_space > 0)
2551 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2555 all->stack_args_size.constant += data->locate.size.constant;
2556 if (data->locate.size.var)
2557 ADD_PARM_SIZE (all->stack_args_size, data->locate.size.var);
2562 /* A subroutine of assign_parms. Given that this parameter is allocated
2563 stack space by the ABI, find it. */
2566 assign_parm_find_stack_rtl (tree parm, struct assign_parm_data_one *data)
2568 rtx offset_rtx, stack_parm;
2569 unsigned int align, boundary;
2571 /* If we're passing this arg using a reg, make its stack home the
2572 aligned stack slot. */
2573 if (data->entry_parm)
2574 offset_rtx = ARGS_SIZE_RTX (data->locate.slot_offset);
2576 offset_rtx = ARGS_SIZE_RTX (data->locate.offset);
2578 stack_parm = crtl->args.internal_arg_pointer;
2579 if (offset_rtx != const0_rtx)
2580 stack_parm = gen_rtx_PLUS (Pmode, stack_parm, offset_rtx);
2581 stack_parm = gen_rtx_MEM (data->promoted_mode, stack_parm);
2583 if (!data->passed_pointer)
2585 set_mem_attributes (stack_parm, parm, 1);
2586 /* set_mem_attributes could set MEM_SIZE to the passed mode's size,
2587 while promoted mode's size is needed. */
2588 if (data->promoted_mode != BLKmode
2589 && data->promoted_mode != DECL_MODE (parm))
2591 set_mem_size (stack_parm,
2592 GEN_INT (GET_MODE_SIZE (data->promoted_mode)));
2593 if (MEM_EXPR (stack_parm) && MEM_OFFSET (stack_parm))
2595 int offset = subreg_lowpart_offset (DECL_MODE (parm),
2596 data->promoted_mode);
2598 set_mem_offset (stack_parm,
2599 plus_constant (MEM_OFFSET (stack_parm),
2605 boundary = data->locate.boundary;
2606 align = BITS_PER_UNIT;
2608 /* If we're padding upward, we know that the alignment of the slot
2609 is TARGET_FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2610 intentionally forcing upward padding. Otherwise we have to come
2611 up with a guess at the alignment based on OFFSET_RTX. */
2612 if (data->locate.where_pad != downward || data->entry_parm)
2614 else if (CONST_INT_P (offset_rtx))
2616 align = INTVAL (offset_rtx) * BITS_PER_UNIT | boundary;
2617 align = align & -align;
2619 set_mem_align (stack_parm, align);
2621 if (data->entry_parm)
2622 set_reg_attrs_for_parm (data->entry_parm, stack_parm);
2624 data->stack_parm = stack_parm;
2627 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2628 always valid and contiguous. */
2631 assign_parm_adjust_entry_rtl (struct assign_parm_data_one *data)
2633 rtx entry_parm = data->entry_parm;
2634 rtx stack_parm = data->stack_parm;
2636 /* If this parm was passed part in regs and part in memory, pretend it
2637 arrived entirely in memory by pushing the register-part onto the stack.
2638 In the special case of a DImode or DFmode that is split, we could put
2639 it together in a pseudoreg directly, but for now that's not worth
2641 if (data->partial != 0)
2643 /* Handle calls that pass values in multiple non-contiguous
2644 locations. The Irix 6 ABI has examples of this. */
2645 if (GET_CODE (entry_parm) == PARALLEL)
2646 emit_group_store (validize_mem (stack_parm), entry_parm,
2648 int_size_in_bytes (data->passed_type));
2651 gcc_assert (data->partial % UNITS_PER_WORD == 0);
2652 move_block_from_reg (REGNO (entry_parm), validize_mem (stack_parm),
2653 data->partial / UNITS_PER_WORD);
2656 entry_parm = stack_parm;
2659 /* If we didn't decide this parm came in a register, by default it came
2661 else if (entry_parm == NULL)
2662 entry_parm = stack_parm;
2664 /* When an argument is passed in multiple locations, we can't make use
2665 of this information, but we can save some copying if the whole argument
2666 is passed in a single register. */
2667 else if (GET_CODE (entry_parm) == PARALLEL
2668 && data->nominal_mode != BLKmode
2669 && data->passed_mode != BLKmode)
2671 size_t i, len = XVECLEN (entry_parm, 0);
2673 for (i = 0; i < len; i++)
2674 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
2675 && REG_P (XEXP (XVECEXP (entry_parm, 0, i), 0))
2676 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
2677 == data->passed_mode)
2678 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
2680 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
2685 data->entry_parm = entry_parm;
2688 /* A subroutine of assign_parms. Reconstitute any values which were
2689 passed in multiple registers and would fit in a single register. */
2692 assign_parm_remove_parallels (struct assign_parm_data_one *data)
2694 rtx entry_parm = data->entry_parm;
2696 /* Convert the PARALLEL to a REG of the same mode as the parallel.
2697 This can be done with register operations rather than on the
2698 stack, even if we will store the reconstituted parameter on the
2700 if (GET_CODE (entry_parm) == PARALLEL && GET_MODE (entry_parm) != BLKmode)
2702 rtx parmreg = gen_reg_rtx (GET_MODE (entry_parm));
2703 emit_group_store (parmreg, entry_parm, data->passed_type,
2704 GET_MODE_SIZE (GET_MODE (entry_parm)));
2705 entry_parm = parmreg;
2708 data->entry_parm = entry_parm;
2711 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2712 always valid and properly aligned. */
2715 assign_parm_adjust_stack_rtl (struct assign_parm_data_one *data)
2717 rtx stack_parm = data->stack_parm;
2719 /* If we can't trust the parm stack slot to be aligned enough for its
2720 ultimate type, don't use that slot after entry. We'll make another
2721 stack slot, if we need one. */
2723 && ((STRICT_ALIGNMENT
2724 && GET_MODE_ALIGNMENT (data->nominal_mode) > MEM_ALIGN (stack_parm))
2725 || (data->nominal_type
2726 && TYPE_ALIGN (data->nominal_type) > MEM_ALIGN (stack_parm)
2727 && MEM_ALIGN (stack_parm) < PREFERRED_STACK_BOUNDARY)))
2730 /* If parm was passed in memory, and we need to convert it on entry,
2731 don't store it back in that same slot. */
2732 else if (data->entry_parm == stack_parm
2733 && data->nominal_mode != BLKmode
2734 && data->nominal_mode != data->passed_mode)
2737 /* If stack protection is in effect for this function, don't leave any
2738 pointers in their passed stack slots. */
2739 else if (crtl->stack_protect_guard
2740 && (flag_stack_protect == 2
2741 || data->passed_pointer
2742 || POINTER_TYPE_P (data->nominal_type)))
2745 data->stack_parm = stack_parm;
2748 /* A subroutine of assign_parms. Return true if the current parameter
2749 should be stored as a BLKmode in the current frame. */
2752 assign_parm_setup_block_p (struct assign_parm_data_one *data)
2754 if (data->nominal_mode == BLKmode)
2756 if (GET_MODE (data->entry_parm) == BLKmode)
2759 #ifdef BLOCK_REG_PADDING
2760 /* Only assign_parm_setup_block knows how to deal with register arguments
2761 that are padded at the least significant end. */
2762 if (REG_P (data->entry_parm)
2763 && GET_MODE_SIZE (data->promoted_mode) < UNITS_PER_WORD
2764 && (BLOCK_REG_PADDING (data->passed_mode, data->passed_type, 1)
2765 == (BYTES_BIG_ENDIAN ? upward : downward)))
2772 /* A subroutine of assign_parms. Arrange for the parameter to be
2773 present and valid in DATA->STACK_RTL. */
2776 assign_parm_setup_block (struct assign_parm_data_all *all,
2777 tree parm, struct assign_parm_data_one *data)
2779 rtx entry_parm = data->entry_parm;
2780 rtx stack_parm = data->stack_parm;
2782 HOST_WIDE_INT size_stored;
2784 if (GET_CODE (entry_parm) == PARALLEL)
2785 entry_parm = emit_group_move_into_temps (entry_parm);
2787 size = int_size_in_bytes (data->passed_type);
2788 size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
2789 if (stack_parm == 0)
2791 DECL_ALIGN (parm) = MAX (DECL_ALIGN (parm), BITS_PER_WORD);
2792 stack_parm = assign_stack_local (BLKmode, size_stored,
2794 if (GET_MODE_SIZE (GET_MODE (entry_parm)) == size)
2795 PUT_MODE (stack_parm, GET_MODE (entry_parm));
2796 set_mem_attributes (stack_parm, parm, 1);
2799 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2800 calls that pass values in multiple non-contiguous locations. */
2801 if (REG_P (entry_parm) || GET_CODE (entry_parm) == PARALLEL)
2805 /* Note that we will be storing an integral number of words.
2806 So we have to be careful to ensure that we allocate an
2807 integral number of words. We do this above when we call
2808 assign_stack_local if space was not allocated in the argument
2809 list. If it was, this will not work if PARM_BOUNDARY is not
2810 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2811 if it becomes a problem. Exception is when BLKmode arrives
2812 with arguments not conforming to word_mode. */
2814 if (data->stack_parm == 0)
2816 else if (GET_CODE (entry_parm) == PARALLEL)
2819 gcc_assert (!size || !(PARM_BOUNDARY % BITS_PER_WORD));
2821 mem = validize_mem (stack_parm);
2823 /* Handle values in multiple non-contiguous locations. */
2824 if (GET_CODE (entry_parm) == PARALLEL)
2826 push_to_sequence2 (all->first_conversion_insn,
2827 all->last_conversion_insn);
2828 emit_group_store (mem, entry_parm, data->passed_type, size);
2829 all->first_conversion_insn = get_insns ();
2830 all->last_conversion_insn = get_last_insn ();
2837 /* If SIZE is that of a mode no bigger than a word, just use
2838 that mode's store operation. */
2839 else if (size <= UNITS_PER_WORD)
2841 enum machine_mode mode
2842 = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
2845 #ifdef BLOCK_REG_PADDING
2846 && (size == UNITS_PER_WORD
2847 || (BLOCK_REG_PADDING (mode, data->passed_type, 1)
2848 != (BYTES_BIG_ENDIAN ? upward : downward)))
2854 /* We are really truncating a word_mode value containing
2855 SIZE bytes into a value of mode MODE. If such an
2856 operation requires no actual instructions, we can refer
2857 to the value directly in mode MODE, otherwise we must
2858 start with the register in word_mode and explicitly
2860 if (TRULY_NOOP_TRUNCATION (size * BITS_PER_UNIT, BITS_PER_WORD))
2861 reg = gen_rtx_REG (mode, REGNO (entry_parm));
2864 reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
2865 reg = convert_to_mode (mode, copy_to_reg (reg), 1);
2867 emit_move_insn (change_address (mem, mode, 0), reg);
2870 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
2871 machine must be aligned to the left before storing
2872 to memory. Note that the previous test doesn't
2873 handle all cases (e.g. SIZE == 3). */
2874 else if (size != UNITS_PER_WORD
2875 #ifdef BLOCK_REG_PADDING
2876 && (BLOCK_REG_PADDING (mode, data->passed_type, 1)
2884 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2885 rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
2887 x = expand_shift (LSHIFT_EXPR, word_mode, reg,
2888 build_int_cst (NULL_TREE, by),
2890 tem = change_address (mem, word_mode, 0);
2891 emit_move_insn (tem, x);
2894 move_block_from_reg (REGNO (entry_parm), mem,
2895 size_stored / UNITS_PER_WORD);
2898 move_block_from_reg (REGNO (entry_parm), mem,
2899 size_stored / UNITS_PER_WORD);
2901 else if (data->stack_parm == 0)
2903 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
2904 emit_block_move (stack_parm, data->entry_parm, GEN_INT (size),
2906 all->first_conversion_insn = get_insns ();
2907 all->last_conversion_insn = get_last_insn ();
2911 data->stack_parm = stack_parm;
2912 SET_DECL_RTL (parm, stack_parm);
2915 /* A subroutine of assign_parm_setup_reg, called through note_stores.
2916 This collects sets and clobbers of hard registers in a HARD_REG_SET,
2917 which is pointed to by DATA. */
2919 record_hard_reg_sets (rtx x, const_rtx pat ATTRIBUTE_UNUSED, void *data)
2921 HARD_REG_SET *pset = (HARD_REG_SET *)data;
2922 if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER)
2924 int nregs = hard_regno_nregs[REGNO (x)][GET_MODE (x)];
2926 SET_HARD_REG_BIT (*pset, REGNO (x) + nregs);
2930 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
2931 parameter. Get it there. Perform all ABI specified conversions. */
2934 assign_parm_setup_reg (struct assign_parm_data_all *all, tree parm,
2935 struct assign_parm_data_one *data)
2937 rtx parmreg, validated_mem;
2938 rtx equiv_stack_parm;
2939 enum machine_mode promoted_nominal_mode;
2940 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (parm));
2941 bool did_conversion = false;
2942 bool need_conversion, moved;
2944 /* Store the parm in a pseudoregister during the function, but we may
2945 need to do it in a wider mode. Using 2 here makes the result
2946 consistent with promote_decl_mode and thus expand_expr_real_1. */
2947 promoted_nominal_mode
2948 = promote_function_mode (data->nominal_type, data->nominal_mode, &unsignedp,
2949 TREE_TYPE (current_function_decl), 2);
2951 parmreg = gen_reg_rtx (promoted_nominal_mode);
2953 if (!DECL_ARTIFICIAL (parm))
2954 mark_user_reg (parmreg);
2956 /* If this was an item that we received a pointer to,
2957 set DECL_RTL appropriately. */
2958 if (data->passed_pointer)
2960 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data->passed_type)), parmreg);
2961 set_mem_attributes (x, parm, 1);
2962 SET_DECL_RTL (parm, x);
2965 SET_DECL_RTL (parm, parmreg);
2967 assign_parm_remove_parallels (data);
2969 /* Copy the value into the register, thus bridging between
2970 assign_parm_find_data_types and expand_expr_real_1. */
2972 equiv_stack_parm = data->stack_parm;
2973 validated_mem = validize_mem (data->entry_parm);
2975 need_conversion = (data->nominal_mode != data->passed_mode
2976 || promoted_nominal_mode != data->promoted_mode);
2980 && GET_MODE_CLASS (data->nominal_mode) == MODE_INT
2981 && data->nominal_mode == data->passed_mode
2982 && data->nominal_mode == GET_MODE (data->entry_parm))
2984 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
2985 mode, by the caller. We now have to convert it to
2986 NOMINAL_MODE, if different. However, PARMREG may be in
2987 a different mode than NOMINAL_MODE if it is being stored
2990 If ENTRY_PARM is a hard register, it might be in a register
2991 not valid for operating in its mode (e.g., an odd-numbered
2992 register for a DFmode). In that case, moves are the only
2993 thing valid, so we can't do a convert from there. This
2994 occurs when the calling sequence allow such misaligned
2997 In addition, the conversion may involve a call, which could
2998 clobber parameters which haven't been copied to pseudo
3001 First, we try to emit an insn which performs the necessary
3002 conversion. We verify that this insn does not clobber any
3005 enum insn_code icode;
3008 icode = can_extend_p (promoted_nominal_mode, data->passed_mode,
3012 op1 = validated_mem;
3013 if (icode != CODE_FOR_nothing
3014 && insn_operand_matches (icode, 0, op0)
3015 && insn_operand_matches (icode, 1, op1))
3017 enum rtx_code code = unsignedp ? ZERO_EXTEND : SIGN_EXTEND;
3019 HARD_REG_SET hardregs;
3022 insn = gen_extend_insn (op0, op1, promoted_nominal_mode,
3023 data->passed_mode, unsignedp);
3025 insns = get_insns ();
3028 CLEAR_HARD_REG_SET (hardregs);
3029 for (insn = insns; insn && moved; insn = NEXT_INSN (insn))
3032 note_stores (PATTERN (insn), record_hard_reg_sets,
3034 if (!hard_reg_set_empty_p (hardregs))
3043 if (equiv_stack_parm != NULL_RTX)
3044 equiv_stack_parm = gen_rtx_fmt_e (code, GET_MODE (parmreg),
3051 /* Nothing to do. */
3053 else if (need_conversion)
3055 /* We did not have an insn to convert directly, or the sequence
3056 generated appeared unsafe. We must first copy the parm to a
3057 pseudo reg, and save the conversion until after all
3058 parameters have been moved. */
3061 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
3063 emit_move_insn (tempreg, validated_mem);
3065 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
3066 tempreg = convert_to_mode (data->nominal_mode, tempreg, unsignedp);
3068 if (GET_CODE (tempreg) == SUBREG
3069 && GET_MODE (tempreg) == data->nominal_mode
3070 && REG_P (SUBREG_REG (tempreg))
3071 && data->nominal_mode == data->passed_mode
3072 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (data->entry_parm)
3073 && GET_MODE_SIZE (GET_MODE (tempreg))
3074 < GET_MODE_SIZE (GET_MODE (data->entry_parm)))
3076 /* The argument is already sign/zero extended, so note it
3078 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
3079 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
3082 /* TREE_USED gets set erroneously during expand_assignment. */
3083 save_tree_used = TREE_USED (parm);
3084 expand_assignment (parm, make_tree (data->nominal_type, tempreg), false);
3085 TREE_USED (parm) = save_tree_used;
3086 all->first_conversion_insn = get_insns ();
3087 all->last_conversion_insn = get_last_insn ();
3090 did_conversion = true;
3093 emit_move_insn (parmreg, validated_mem);
3095 /* If we were passed a pointer but the actual value can safely live
3096 in a register, put it in one. */
3097 if (data->passed_pointer
3098 && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
3099 /* If by-reference argument was promoted, demote it. */
3100 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
3101 || use_register_for_decl (parm)))
3103 /* We can't use nominal_mode, because it will have been set to
3104 Pmode above. We must use the actual mode of the parm. */
3105 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
3106 mark_user_reg (parmreg);
3108 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
3110 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
3111 int unsigned_p = TYPE_UNSIGNED (TREE_TYPE (parm));
3113 push_to_sequence2 (all->first_conversion_insn,
3114 all->last_conversion_insn);
3115 emit_move_insn (tempreg, DECL_RTL (parm));
3116 tempreg = convert_to_mode (GET_MODE (parmreg), tempreg, unsigned_p);
3117 emit_move_insn (parmreg, tempreg);
3118 all->first_conversion_insn = get_insns ();
3119 all->last_conversion_insn = get_last_insn ();
3122 did_conversion = true;
3125 emit_move_insn (parmreg, DECL_RTL (parm));
3127 SET_DECL_RTL (parm, parmreg);
3129 /* STACK_PARM is the pointer, not the parm, and PARMREG is
3131 data->stack_parm = NULL;
3134 /* Mark the register as eliminable if we did no conversion and it was
3135 copied from memory at a fixed offset, and the arg pointer was not
3136 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
3137 offset formed an invalid address, such memory-equivalences as we
3138 make here would screw up life analysis for it. */
3139 if (data->nominal_mode == data->passed_mode
3141 && data->stack_parm != 0
3142 && MEM_P (data->stack_parm)
3143 && data->locate.offset.var == 0
3144 && reg_mentioned_p (virtual_incoming_args_rtx,
3145 XEXP (data->stack_parm, 0)))
3147 rtx linsn = get_last_insn ();
3150 /* Mark complex types separately. */
3151 if (GET_CODE (parmreg) == CONCAT)
3153 enum machine_mode submode
3154 = GET_MODE_INNER (GET_MODE (parmreg));
3155 int regnor = REGNO (XEXP (parmreg, 0));
3156 int regnoi = REGNO (XEXP (parmreg, 1));
3157 rtx stackr = adjust_address_nv (data->stack_parm, submode, 0);
3158 rtx stacki = adjust_address_nv (data->stack_parm, submode,
3159 GET_MODE_SIZE (submode));
3161 /* Scan backwards for the set of the real and
3163 for (sinsn = linsn; sinsn != 0;
3164 sinsn = prev_nonnote_insn (sinsn))
3166 set = single_set (sinsn);
3170 if (SET_DEST (set) == regno_reg_rtx [regnoi])
3171 set_unique_reg_note (sinsn, REG_EQUIV, stacki);
3172 else if (SET_DEST (set) == regno_reg_rtx [regnor])
3173 set_unique_reg_note (sinsn, REG_EQUIV, stackr);
3176 else if ((set = single_set (linsn)) != 0
3177 && SET_DEST (set) == parmreg)
3178 set_unique_reg_note (linsn, REG_EQUIV, equiv_stack_parm);
3181 /* For pointer data type, suggest pointer register. */
3182 if (POINTER_TYPE_P (TREE_TYPE (parm)))
3183 mark_reg_pointer (parmreg,
3184 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
3187 /* A subroutine of assign_parms. Allocate stack space to hold the current
3188 parameter. Get it there. Perform all ABI specified conversions. */
3191 assign_parm_setup_stack (struct assign_parm_data_all *all, tree parm,
3192 struct assign_parm_data_one *data)
3194 /* Value must be stored in the stack slot STACK_PARM during function
3196 bool to_conversion = false;
3198 assign_parm_remove_parallels (data);
3200 if (data->promoted_mode != data->nominal_mode)
3202 /* Conversion is required. */
3203 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
3205 emit_move_insn (tempreg, validize_mem (data->entry_parm));
3207 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
3208 to_conversion = true;
3210 data->entry_parm = convert_to_mode (data->nominal_mode, tempreg,
3211 TYPE_UNSIGNED (TREE_TYPE (parm)));
3213 if (data->stack_parm)
3215 int offset = subreg_lowpart_offset (data->nominal_mode,
3216 GET_MODE (data->stack_parm));
3217 /* ??? This may need a big-endian conversion on sparc64. */
3219 = adjust_address (data->stack_parm, data->nominal_mode, 0);
3220 if (offset && MEM_OFFSET (data->stack_parm))
3221 set_mem_offset (data->stack_parm,
3222 plus_constant (MEM_OFFSET (data->stack_parm),
3227 if (data->entry_parm != data->stack_parm)
3231 if (data->stack_parm == 0)
3233 int align = STACK_SLOT_ALIGNMENT (data->passed_type,
3234 GET_MODE (data->entry_parm),
3235 TYPE_ALIGN (data->passed_type));
3237 = assign_stack_local (GET_MODE (data->entry_parm),
3238 GET_MODE_SIZE (GET_MODE (data->entry_parm)),
3240 set_mem_attributes (data->stack_parm, parm, 1);
3243 dest = validize_mem (data->stack_parm);
3244 src = validize_mem (data->entry_parm);
3248 /* Use a block move to handle potentially misaligned entry_parm. */
3250 push_to_sequence2 (all->first_conversion_insn,
3251 all->last_conversion_insn);
3252 to_conversion = true;
3254 emit_block_move (dest, src,
3255 GEN_INT (int_size_in_bytes (data->passed_type)),
3259 emit_move_insn (dest, src);
3264 all->first_conversion_insn = get_insns ();
3265 all->last_conversion_insn = get_last_insn ();
3269 SET_DECL_RTL (parm, data->stack_parm);
3272 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
3273 undo the frobbing that we did in assign_parms_augmented_arg_list. */
3276 assign_parms_unsplit_complex (struct assign_parm_data_all *all,
3277 VEC(tree, heap) *fnargs)
3280 tree orig_fnargs = all->orig_fnargs;
3283 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm), ++i)
3285 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE
3286 && targetm.calls.split_complex_arg (TREE_TYPE (parm)))
3288 rtx tmp, real, imag;
3289 enum machine_mode inner = GET_MODE_INNER (DECL_MODE (parm));
3291 real = DECL_RTL (VEC_index (tree, fnargs, i));
3292 imag = DECL_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);
3299 if (TREE_ADDRESSABLE (parm))
3302 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (parm));
3303 int align = STACK_SLOT_ALIGNMENT (TREE_TYPE (parm),
3305 TYPE_ALIGN (TREE_TYPE (parm)));
3307 /* split_complex_arg put the real and imag parts in
3308 pseudos. Move them to memory. */
3309 tmp = assign_stack_local (DECL_MODE (parm), size, align);
3310 set_mem_attributes (tmp, parm, 1);
3311 rmem = adjust_address_nv (tmp, inner, 0);
3312 imem = adjust_address_nv (tmp, inner, GET_MODE_SIZE (inner));
3313 push_to_sequence2 (all->first_conversion_insn,
3314 all->last_conversion_insn);
3315 emit_move_insn (rmem, real);
3316 emit_move_insn (imem, imag);
3317 all->first_conversion_insn = get_insns ();
3318 all->last_conversion_insn = get_last_insn ();
3322 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3323 SET_DECL_RTL (parm, tmp);
3325 real = DECL_INCOMING_RTL (VEC_index (tree, fnargs, i));
3326 imag = DECL_INCOMING_RTL (VEC_index (tree, fnargs, i + 1));
3327 if (inner != GET_MODE (real))
3329 real = gen_lowpart_SUBREG (inner, real);
3330 imag = gen_lowpart_SUBREG (inner, imag);
3332 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3333 set_decl_incoming_rtl (parm, tmp, false);
3339 /* Assign RTL expressions to the function's parameters. This may involve
3340 copying them into registers and using those registers as the DECL_RTL. */
3343 assign_parms (tree fndecl)
3345 struct assign_parm_data_all all;
3347 VEC(tree, heap) *fnargs;
3350 crtl->args.internal_arg_pointer
3351 = targetm.calls.internal_arg_pointer ();
3353 assign_parms_initialize_all (&all);
3354 fnargs = assign_parms_augmented_arg_list (&all);
3356 FOR_EACH_VEC_ELT (tree, fnargs, i, parm)
3358 struct assign_parm_data_one data;
3360 /* Extract the type of PARM; adjust it according to ABI. */
3361 assign_parm_find_data_types (&all, parm, &data);
3363 /* Early out for errors and void parameters. */
3364 if (data.passed_mode == VOIDmode)
3366 SET_DECL_RTL (parm, const0_rtx);
3367 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
3371 /* Estimate stack alignment from parameter alignment. */
3372 if (SUPPORTS_STACK_ALIGNMENT)
3375 = targetm.calls.function_arg_boundary (data.promoted_mode,
3377 align = MINIMUM_ALIGNMENT (data.passed_type, data.promoted_mode,
3379 if (TYPE_ALIGN (data.nominal_type) > align)
3380 align = MINIMUM_ALIGNMENT (data.nominal_type,
3381 TYPE_MODE (data.nominal_type),
3382 TYPE_ALIGN (data.nominal_type));
3383 if (crtl->stack_alignment_estimated < align)
3385 gcc_assert (!crtl->stack_realign_processed);
3386 crtl->stack_alignment_estimated = align;
3390 if (cfun->stdarg && !DECL_CHAIN (parm))
3391 assign_parms_setup_varargs (&all, &data, false);
3393 /* Find out where the parameter arrives in this function. */
3394 assign_parm_find_entry_rtl (&all, &data);
3396 /* Find out where stack space for this parameter might be. */
3397 if (assign_parm_is_stack_parm (&all, &data))
3399 assign_parm_find_stack_rtl (parm, &data);
3400 assign_parm_adjust_entry_rtl (&data);
3403 /* Record permanently how this parm was passed. */
3404 if (data.passed_pointer)
3407 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data.passed_type)),
3409 set_decl_incoming_rtl (parm, incoming_rtl, true);
3412 set_decl_incoming_rtl (parm, data.entry_parm, false);
3414 /* Update info on where next arg arrives in registers. */
3415 targetm.calls.function_arg_advance (&all.args_so_far, data.promoted_mode,
3416 data.passed_type, data.named_arg);
3418 assign_parm_adjust_stack_rtl (&data);
3420 if (assign_parm_setup_block_p (&data))
3421 assign_parm_setup_block (&all, parm, &data);
3422 else if (data.passed_pointer || use_register_for_decl (parm))
3423 assign_parm_setup_reg (&all, parm, &data);
3425 assign_parm_setup_stack (&all, parm, &data);
3428 if (targetm.calls.split_complex_arg)
3429 assign_parms_unsplit_complex (&all, fnargs);
3431 VEC_free (tree, heap, fnargs);
3433 /* Output all parameter conversion instructions (possibly including calls)
3434 now that all parameters have been copied out of hard registers. */
3435 emit_insn (all.first_conversion_insn);
3437 /* Estimate reload stack alignment from scalar return mode. */
3438 if (SUPPORTS_STACK_ALIGNMENT)
3440 if (DECL_RESULT (fndecl))
3442 tree type = TREE_TYPE (DECL_RESULT (fndecl));
3443 enum machine_mode mode = TYPE_MODE (type);
3447 && !AGGREGATE_TYPE_P (type))
3449 unsigned int align = GET_MODE_ALIGNMENT (mode);
3450 if (crtl->stack_alignment_estimated < align)
3452 gcc_assert (!crtl->stack_realign_processed);
3453 crtl->stack_alignment_estimated = align;
3459 /* If we are receiving a struct value address as the first argument, set up
3460 the RTL for the function result. As this might require code to convert
3461 the transmitted address to Pmode, we do this here to ensure that possible
3462 preliminary conversions of the address have been emitted already. */
3463 if (all.function_result_decl)
3465 tree result = DECL_RESULT (current_function_decl);
3466 rtx addr = DECL_RTL (all.function_result_decl);
3469 if (DECL_BY_REFERENCE (result))
3471 SET_DECL_VALUE_EXPR (result, all.function_result_decl);
3476 SET_DECL_VALUE_EXPR (result,
3477 build1 (INDIRECT_REF, TREE_TYPE (result),
3478 all.function_result_decl));
3479 addr = convert_memory_address (Pmode, addr);
3480 x = gen_rtx_MEM (DECL_MODE (result), addr);
3481 set_mem_attributes (x, result, 1);
3484 DECL_HAS_VALUE_EXPR_P (result) = 1;
3486 SET_DECL_RTL (result, x);
3489 /* We have aligned all the args, so add space for the pretend args. */
3490 crtl->args.pretend_args_size = all.pretend_args_size;
3491 all.stack_args_size.constant += all.extra_pretend_bytes;
3492 crtl->args.size = all.stack_args_size.constant;
3494 /* Adjust function incoming argument size for alignment and
3497 #ifdef REG_PARM_STACK_SPACE
3498 crtl->args.size = MAX (crtl->args.size,
3499 REG_PARM_STACK_SPACE (fndecl));
3502 crtl->args.size = CEIL_ROUND (crtl->args.size,
3503 PARM_BOUNDARY / BITS_PER_UNIT);
3505 #ifdef ARGS_GROW_DOWNWARD
3506 crtl->args.arg_offset_rtx
3507 = (all.stack_args_size.var == 0 ? GEN_INT (-all.stack_args_size.constant)
3508 : expand_expr (size_diffop (all.stack_args_size.var,
3509 size_int (-all.stack_args_size.constant)),
3510 NULL_RTX, VOIDmode, EXPAND_NORMAL));
3512 crtl->args.arg_offset_rtx = ARGS_SIZE_RTX (all.stack_args_size);
3515 /* See how many bytes, if any, of its args a function should try to pop
3518 crtl->args.pops_args = targetm.calls.return_pops_args (fndecl,
3522 /* For stdarg.h function, save info about
3523 regs and stack space used by the named args. */
3525 crtl->args.info = all.args_so_far;
3527 /* Set the rtx used for the function return value. Put this in its
3528 own variable so any optimizers that need this information don't have
3529 to include tree.h. Do this here so it gets done when an inlined
3530 function gets output. */
3533 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
3534 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
3536 /* If scalar return value was computed in a pseudo-reg, or was a named
3537 return value that got dumped to the stack, copy that to the hard
3539 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
3541 tree decl_result = DECL_RESULT (fndecl);
3542 rtx decl_rtl = DECL_RTL (decl_result);
3544 if (REG_P (decl_rtl)
3545 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
3546 : DECL_REGISTER (decl_result))
3550 real_decl_rtl = targetm.calls.function_value (TREE_TYPE (decl_result),
3552 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
3553 /* The delay slot scheduler assumes that crtl->return_rtx
3554 holds the hard register containing the return value, not a
3555 temporary pseudo. */
3556 crtl->return_rtx = real_decl_rtl;
3561 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3562 For all seen types, gimplify their sizes. */
3565 gimplify_parm_type (tree *tp, int *walk_subtrees, void *data)
3572 if (POINTER_TYPE_P (t))
3574 else if (TYPE_SIZE (t) && !TREE_CONSTANT (TYPE_SIZE (t))
3575 && !TYPE_SIZES_GIMPLIFIED (t))
3577 gimplify_type_sizes (t, (gimple_seq *) data);
3585 /* Gimplify the parameter list for current_function_decl. This involves
3586 evaluating SAVE_EXPRs of variable sized parameters and generating code
3587 to implement callee-copies reference parameters. Returns a sequence of
3588 statements to add to the beginning of the function. */
3591 gimplify_parameters (void)
3593 struct assign_parm_data_all all;
3595 gimple_seq stmts = NULL;
3596 VEC(tree, heap) *fnargs;
3599 assign_parms_initialize_all (&all);
3600 fnargs = assign_parms_augmented_arg_list (&all);
3602 FOR_EACH_VEC_ELT (tree, fnargs, i, parm)
3604 struct assign_parm_data_one data;
3606 /* Extract the type of PARM; adjust it according to ABI. */
3607 assign_parm_find_data_types (&all, parm, &data);
3609 /* Early out for errors and void parameters. */
3610 if (data.passed_mode == VOIDmode || DECL_SIZE (parm) == NULL)
3613 /* Update info on where next arg arrives in registers. */
3614 targetm.calls.function_arg_advance (&all.args_so_far, data.promoted_mode,
3615 data.passed_type, data.named_arg);
3617 /* ??? Once upon a time variable_size stuffed parameter list
3618 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3619 turned out to be less than manageable in the gimple world.
3620 Now we have to hunt them down ourselves. */
3621 walk_tree_without_duplicates (&data.passed_type,
3622 gimplify_parm_type, &stmts);
3624 if (TREE_CODE (DECL_SIZE_UNIT (parm)) != INTEGER_CST)
3626 gimplify_one_sizepos (&DECL_SIZE (parm), &stmts);
3627 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm), &stmts);
3630 if (data.passed_pointer)
3632 tree type = TREE_TYPE (data.passed_type);
3633 if (reference_callee_copied (&all.args_so_far, TYPE_MODE (type),
3634 type, data.named_arg))
3638 /* For constant-sized objects, this is trivial; for
3639 variable-sized objects, we have to play games. */
3640 if (TREE_CODE (DECL_SIZE_UNIT (parm)) == INTEGER_CST
3641 && !(flag_stack_check == GENERIC_STACK_CHECK
3642 && compare_tree_int (DECL_SIZE_UNIT (parm),
3643 STACK_CHECK_MAX_VAR_SIZE) > 0))
3645 local = create_tmp_reg (type, get_name (parm));
3646 DECL_IGNORED_P (local) = 0;
3647 /* If PARM was addressable, move that flag over
3648 to the local copy, as its address will be taken,
3649 not the PARMs. Keep the parms address taken
3650 as we'll query that flag during gimplification. */
3651 if (TREE_ADDRESSABLE (parm))
3652 TREE_ADDRESSABLE (local) = 1;
3656 tree ptr_type, addr;
3658 ptr_type = build_pointer_type (type);
3659 addr = create_tmp_reg (ptr_type, get_name (parm));
3660 DECL_IGNORED_P (addr) = 0;
3661 local = build_fold_indirect_ref (addr);
3663 t = built_in_decls[BUILT_IN_ALLOCA];
3664 t = build_call_expr (t, 1, DECL_SIZE_UNIT (parm));
3665 /* The call has been built for a variable-sized object. */
3666 ALLOCA_FOR_VAR_P (t) = 1;
3667 t = fold_convert (ptr_type, t);
3668 t = build2 (MODIFY_EXPR, TREE_TYPE (addr), addr, t);
3669 gimplify_and_add (t, &stmts);
3672 gimplify_assign (local, parm, &stmts);
3674 SET_DECL_VALUE_EXPR (parm, local);
3675 DECL_HAS_VALUE_EXPR_P (parm) = 1;
3680 VEC_free (tree, heap, fnargs);
3685 /* Compute the size and offset from the start of the stacked arguments for a
3686 parm passed in mode PASSED_MODE and with type TYPE.
3688 INITIAL_OFFSET_PTR points to the current offset into the stacked
3691 The starting offset and size for this parm are returned in
3692 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3693 nonzero, the offset is that of stack slot, which is returned in
3694 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3695 padding required from the initial offset ptr to the stack slot.
3697 IN_REGS is nonzero if the argument will be passed in registers. It will
3698 never be set if REG_PARM_STACK_SPACE is not defined.
3700 FNDECL is the function in which the argument was defined.
3702 There are two types of rounding that are done. The first, controlled by
3703 TARGET_FUNCTION_ARG_BOUNDARY, forces the offset from the start of the
3704 argument list to be aligned to the specific boundary (in bits). This
3705 rounding affects the initial and starting offsets, but not the argument
3708 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3709 optionally rounds the size of the parm to PARM_BOUNDARY. The
3710 initial offset is not affected by this rounding, while the size always
3711 is and the starting offset may be. */
3713 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3714 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3715 callers pass in the total size of args so far as
3716 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
3719 locate_and_pad_parm (enum machine_mode passed_mode, tree type, int in_regs,
3720 int partial, tree fndecl ATTRIBUTE_UNUSED,
3721 struct args_size *initial_offset_ptr,
3722 struct locate_and_pad_arg_data *locate)
3725 enum direction where_pad;
3726 unsigned int boundary;
3727 int reg_parm_stack_space = 0;
3728 int part_size_in_regs;
3730 #ifdef REG_PARM_STACK_SPACE
3731 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
3733 /* If we have found a stack parm before we reach the end of the
3734 area reserved for registers, skip that area. */
3737 if (reg_parm_stack_space > 0)
3739 if (initial_offset_ptr->var)
3741 initial_offset_ptr->var
3742 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
3743 ssize_int (reg_parm_stack_space));
3744 initial_offset_ptr->constant = 0;
3746 else if (initial_offset_ptr->constant < reg_parm_stack_space)
3747 initial_offset_ptr->constant = reg_parm_stack_space;
3750 #endif /* REG_PARM_STACK_SPACE */
3752 part_size_in_regs = (reg_parm_stack_space == 0 ? partial : 0);
3755 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
3756 where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
3757 boundary = targetm.calls.function_arg_boundary (passed_mode, type);
3758 locate->where_pad = where_pad;
3760 /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT. */
3761 if (boundary > MAX_SUPPORTED_STACK_ALIGNMENT)
3762 boundary = MAX_SUPPORTED_STACK_ALIGNMENT;
3764 locate->boundary = boundary;
3766 if (SUPPORTS_STACK_ALIGNMENT)
3768 /* stack_alignment_estimated can't change after stack has been
3770 if (crtl->stack_alignment_estimated < boundary)
3772 if (!crtl->stack_realign_processed)
3773 crtl->stack_alignment_estimated = boundary;
3776 /* If stack is realigned and stack alignment value
3777 hasn't been finalized, it is OK not to increase
3778 stack_alignment_estimated. The bigger alignment
3779 requirement is recorded in stack_alignment_needed
3781 gcc_assert (!crtl->stack_realign_finalized
3782 && crtl->stack_realign_needed);
3787 /* Remember if the outgoing parameter requires extra alignment on the
3788 calling function side. */
3789 if (crtl->stack_alignment_needed < boundary)
3790 crtl->stack_alignment_needed = boundary;
3791 if (crtl->preferred_stack_boundary < boundary)
3792 crtl->preferred_stack_boundary = boundary;
3794 #ifdef ARGS_GROW_DOWNWARD
3795 locate->slot_offset.constant = -initial_offset_ptr->constant;
3796 if (initial_offset_ptr->var)
3797 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
3798 initial_offset_ptr->var);
3802 if (where_pad != none
3803 && (!host_integerp (sizetree, 1)
3804 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
3805 s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
3806 SUB_PARM_SIZE (locate->slot_offset, s2);
3809 locate->slot_offset.constant += part_size_in_regs;
3812 #ifdef REG_PARM_STACK_SPACE
3813 || REG_PARM_STACK_SPACE (fndecl) > 0
3816 pad_to_arg_alignment (&locate->slot_offset, boundary,
3817 &locate->alignment_pad);
3819 locate->size.constant = (-initial_offset_ptr->constant
3820 - locate->slot_offset.constant);
3821 if (initial_offset_ptr->var)
3822 locate->size.var = size_binop (MINUS_EXPR,
3823 size_binop (MINUS_EXPR,
3825 initial_offset_ptr->var),
3826 locate->slot_offset.var);
3828 /* Pad_below needs the pre-rounded size to know how much to pad
3830 locate->offset = locate->slot_offset;
3831 if (where_pad == downward)
3832 pad_below (&locate->offset, passed_mode, sizetree);
3834 #else /* !ARGS_GROW_DOWNWARD */
3836 #ifdef REG_PARM_STACK_SPACE
3837 || REG_PARM_STACK_SPACE (fndecl) > 0
3840 pad_to_arg_alignment (initial_offset_ptr, boundary,
3841 &locate->alignment_pad);
3842 locate->slot_offset = *initial_offset_ptr;
3844 #ifdef PUSH_ROUNDING
3845 if (passed_mode != BLKmode)
3846 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
3849 /* Pad_below needs the pre-rounded size to know how much to pad below
3850 so this must be done before rounding up. */
3851 locate->offset = locate->slot_offset;
3852 if (where_pad == downward)
3853 pad_below (&locate->offset, passed_mode, sizetree);
3855 if (where_pad != none
3856 && (!host_integerp (sizetree, 1)
3857 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
3858 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
3860 ADD_PARM_SIZE (locate->size, sizetree);
3862 locate->size.constant -= part_size_in_regs;
3863 #endif /* ARGS_GROW_DOWNWARD */
3865 #ifdef FUNCTION_ARG_OFFSET
3866 locate->offset.constant += FUNCTION_ARG_OFFSET (passed_mode, type);
3870 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
3871 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
3874 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
3875 struct args_size *alignment_pad)
3877 tree save_var = NULL_TREE;
3878 HOST_WIDE_INT save_constant = 0;
3879 int boundary_in_bytes = boundary / BITS_PER_UNIT;
3880 HOST_WIDE_INT sp_offset = STACK_POINTER_OFFSET;
3882 #ifdef SPARC_STACK_BOUNDARY_HACK
3883 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
3884 the real alignment of %sp. However, when it does this, the
3885 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
3886 if (SPARC_STACK_BOUNDARY_HACK)
3890 if (boundary > PARM_BOUNDARY)
3892 save_var = offset_ptr->var;
3893 save_constant = offset_ptr->constant;
3896 alignment_pad->var = NULL_TREE;
3897 alignment_pad->constant = 0;
3899 if (boundary > BITS_PER_UNIT)
3901 if (offset_ptr->var)
3903 tree sp_offset_tree = ssize_int (sp_offset);
3904 tree offset = size_binop (PLUS_EXPR,
3905 ARGS_SIZE_TREE (*offset_ptr),
3907 #ifdef ARGS_GROW_DOWNWARD
3908 tree rounded = round_down (offset, boundary / BITS_PER_UNIT);
3910 tree rounded = round_up (offset, boundary / BITS_PER_UNIT);
3913 offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
3914 /* ARGS_SIZE_TREE includes constant term. */
3915 offset_ptr->constant = 0;
3916 if (boundary > PARM_BOUNDARY)
3917 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
3922 offset_ptr->constant = -sp_offset +
3923 #ifdef ARGS_GROW_DOWNWARD
3924 FLOOR_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
3926 CEIL_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
3928 if (boundary > PARM_BOUNDARY)
3929 alignment_pad->constant = offset_ptr->constant - save_constant;
3935 pad_below (struct args_size *offset_ptr, enum machine_mode passed_mode, tree sizetree)
3937 if (passed_mode != BLKmode)
3939 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
3940 offset_ptr->constant
3941 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
3942 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
3943 - GET_MODE_SIZE (passed_mode));
3947 if (TREE_CODE (sizetree) != INTEGER_CST
3948 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
3950 /* Round the size up to multiple of PARM_BOUNDARY bits. */
3951 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
3953 ADD_PARM_SIZE (*offset_ptr, s2);
3954 SUB_PARM_SIZE (*offset_ptr, sizetree);
3960 /* True if register REGNO was alive at a place where `setjmp' was
3961 called and was set more than once or is an argument. Such regs may
3962 be clobbered by `longjmp'. */
3965 regno_clobbered_at_setjmp (bitmap setjmp_crosses, int regno)
3967 /* There appear to be cases where some local vars never reach the
3968 backend but have bogus regnos. */
3969 if (regno >= max_reg_num ())
3972 return ((REG_N_SETS (regno) > 1
3973 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR), regno))
3974 && REGNO_REG_SET_P (setjmp_crosses, regno));
3977 /* Walk the tree of blocks describing the binding levels within a
3978 function and warn about variables the might be killed by setjmp or
3979 vfork. This is done after calling flow_analysis before register
3980 allocation since that will clobber the pseudo-regs to hard
3984 setjmp_vars_warning (bitmap setjmp_crosses, tree block)
3988 for (decl = BLOCK_VARS (block); decl; decl = DECL_CHAIN (decl))
3990 if (TREE_CODE (decl) == VAR_DECL
3991 && DECL_RTL_SET_P (decl)
3992 && REG_P (DECL_RTL (decl))
3993 && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
3994 warning (OPT_Wclobbered, "variable %q+D might be clobbered by"
3995 " %<longjmp%> or %<vfork%>", decl);
3998 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = BLOCK_CHAIN (sub))
3999 setjmp_vars_warning (setjmp_crosses, sub);
4002 /* Do the appropriate part of setjmp_vars_warning
4003 but for arguments instead of local variables. */
4006 setjmp_args_warning (bitmap setjmp_crosses)
4009 for (decl = DECL_ARGUMENTS (current_function_decl);
4010 decl; decl = DECL_CHAIN (decl))
4011 if (DECL_RTL (decl) != 0
4012 && REG_P (DECL_RTL (decl))
4013 && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
4014 warning (OPT_Wclobbered,
4015 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
4019 /* Generate warning messages for variables live across setjmp. */
4022 generate_setjmp_warnings (void)
4024 bitmap setjmp_crosses = regstat_get_setjmp_crosses ();
4026 if (n_basic_blocks == NUM_FIXED_BLOCKS
4027 || bitmap_empty_p (setjmp_crosses))
4030 setjmp_vars_warning (setjmp_crosses, DECL_INITIAL (current_function_decl));
4031 setjmp_args_warning (setjmp_crosses);
4035 /* Reverse the order of elements in the fragment chain T of blocks,
4036 and return the new head of the chain (old last element). */
4039 block_fragments_nreverse (tree t)
4041 tree prev = 0, block, next;
4042 for (block = t; block; block = next)
4044 next = BLOCK_FRAGMENT_CHAIN (block);
4045 BLOCK_FRAGMENT_CHAIN (block) = prev;
4051 /* Reverse the order of elements in the chain T of blocks,
4052 and return the new head of the chain (old last element).
4053 Also do the same on subblocks and reverse the order of elements
4054 in BLOCK_FRAGMENT_CHAIN as well. */
4057 blocks_nreverse_all (tree t)
4059 tree prev = 0, block, next;
4060 for (block = t; block; block = next)
4062 next = BLOCK_CHAIN (block);
4063 BLOCK_CHAIN (block) = prev;
4064 BLOCK_SUBBLOCKS (block) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block));
4065 if (BLOCK_FRAGMENT_CHAIN (block)
4066 && BLOCK_FRAGMENT_ORIGIN (block) == NULL_TREE)
4067 BLOCK_FRAGMENT_CHAIN (block)
4068 = block_fragments_nreverse (BLOCK_FRAGMENT_CHAIN (block));
4075 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
4076 and create duplicate blocks. */
4077 /* ??? Need an option to either create block fragments or to create
4078 abstract origin duplicates of a source block. It really depends
4079 on what optimization has been performed. */
4082 reorder_blocks (void)
4084 tree block = DECL_INITIAL (current_function_decl);
4085 VEC(tree,heap) *block_stack;
4087 if (block == NULL_TREE)
4090 block_stack = VEC_alloc (tree, heap, 10);
4092 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
4093 clear_block_marks (block);
4095 /* Prune the old trees away, so that they don't get in the way. */
4096 BLOCK_SUBBLOCKS (block) = NULL_TREE;
4097 BLOCK_CHAIN (block) = NULL_TREE;
4099 /* Recreate the block tree from the note nesting. */
4100 reorder_blocks_1 (get_insns (), block, &block_stack);
4101 BLOCK_SUBBLOCKS (block) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block));
4103 VEC_free (tree, heap, block_stack);
4106 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
4109 clear_block_marks (tree block)
4113 TREE_ASM_WRITTEN (block) = 0;
4114 clear_block_marks (BLOCK_SUBBLOCKS (block));
4115 block = BLOCK_CHAIN (block);
4120 reorder_blocks_1 (rtx insns, tree current_block, VEC(tree,heap) **p_block_stack)
4124 for (insn = insns; insn; insn = NEXT_INSN (insn))
4128 if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_BEG)
4130 tree block = NOTE_BLOCK (insn);
4133 gcc_assert (BLOCK_FRAGMENT_ORIGIN (block) == NULL_TREE);
4136 /* If we have seen this block before, that means it now
4137 spans multiple address regions. Create a new fragment. */
4138 if (TREE_ASM_WRITTEN (block))
4140 tree new_block = copy_node (block);
4142 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
4143 BLOCK_FRAGMENT_CHAIN (new_block)
4144 = BLOCK_FRAGMENT_CHAIN (origin);
4145 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
4147 NOTE_BLOCK (insn) = new_block;
4151 BLOCK_SUBBLOCKS (block) = 0;
4152 TREE_ASM_WRITTEN (block) = 1;
4153 /* When there's only one block for the entire function,
4154 current_block == block and we mustn't do this, it
4155 will cause infinite recursion. */
4156 if (block != current_block)
4158 if (block != origin)
4159 gcc_assert (BLOCK_SUPERCONTEXT (origin) == current_block);
4161 BLOCK_SUPERCONTEXT (block) = current_block;
4162 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
4163 BLOCK_SUBBLOCKS (current_block) = block;
4164 current_block = origin;
4166 VEC_safe_push (tree, heap, *p_block_stack, block);
4168 else if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_END)
4170 NOTE_BLOCK (insn) = VEC_pop (tree, *p_block_stack);
4171 current_block = BLOCK_SUPERCONTEXT (current_block);
4177 /* Reverse the order of elements in the chain T of blocks,
4178 and return the new head of the chain (old last element). */
4181 blocks_nreverse (tree t)
4183 tree prev = 0, block, next;
4184 for (block = t; block; block = next)
4186 next = BLOCK_CHAIN (block);
4187 BLOCK_CHAIN (block) = prev;
4193 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
4194 non-NULL, list them all into VECTOR, in a depth-first preorder
4195 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
4199 all_blocks (tree block, tree *vector)
4205 TREE_ASM_WRITTEN (block) = 0;
4207 /* Record this block. */
4209 vector[n_blocks] = block;
4213 /* Record the subblocks, and their subblocks... */
4214 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
4215 vector ? vector + n_blocks : 0);
4216 block = BLOCK_CHAIN (block);
4222 /* Return a vector containing all the blocks rooted at BLOCK. The
4223 number of elements in the vector is stored in N_BLOCKS_P. The
4224 vector is dynamically allocated; it is the caller's responsibility
4225 to call `free' on the pointer returned. */
4228 get_block_vector (tree block, int *n_blocks_p)
4232 *n_blocks_p = all_blocks (block, NULL);
4233 block_vector = XNEWVEC (tree, *n_blocks_p);
4234 all_blocks (block, block_vector);
4236 return block_vector;
4239 static GTY(()) int next_block_index = 2;
4241 /* Set BLOCK_NUMBER for all the blocks in FN. */
4244 number_blocks (tree fn)
4250 /* For SDB and XCOFF debugging output, we start numbering the blocks
4251 from 1 within each function, rather than keeping a running
4253 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
4254 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
4255 next_block_index = 1;
4258 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
4260 /* The top-level BLOCK isn't numbered at all. */
4261 for (i = 1; i < n_blocks; ++i)
4262 /* We number the blocks from two. */
4263 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
4265 free (block_vector);
4270 /* If VAR is present in a subblock of BLOCK, return the subblock. */
4273 debug_find_var_in_block_tree (tree var, tree block)
4277 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
4281 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
4283 tree ret = debug_find_var_in_block_tree (var, t);
4291 /* Keep track of whether we're in a dummy function context. If we are,
4292 we don't want to invoke the set_current_function hook, because we'll
4293 get into trouble if the hook calls target_reinit () recursively or
4294 when the initial initialization is not yet complete. */
4296 static bool in_dummy_function;
4298 /* Invoke the target hook when setting cfun. Update the optimization options
4299 if the function uses different options than the default. */
4302 invoke_set_current_function_hook (tree fndecl)
4304 if (!in_dummy_function)
4306 tree opts = ((fndecl)
4307 ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl)
4308 : optimization_default_node);
4311 opts = optimization_default_node;
4313 /* Change optimization options if needed. */
4314 if (optimization_current_node != opts)
4316 optimization_current_node = opts;
4317 cl_optimization_restore (&global_options, TREE_OPTIMIZATION (opts));
4320 targetm.set_current_function (fndecl);
4324 /* cfun should never be set directly; use this function. */
4327 set_cfun (struct function *new_cfun)
4329 if (cfun != new_cfun)
4332 invoke_set_current_function_hook (new_cfun ? new_cfun->decl : NULL_TREE);
4336 /* Initialized with NOGC, making this poisonous to the garbage collector. */
4338 static VEC(function_p,heap) *cfun_stack;
4340 /* Push the current cfun onto the stack, and set cfun to new_cfun. */
4343 push_cfun (struct function *new_cfun)
4345 VEC_safe_push (function_p, heap, cfun_stack, cfun);
4346 set_cfun (new_cfun);
4349 /* Pop cfun from the stack. */
4354 struct function *new_cfun = VEC_pop (function_p, cfun_stack);
4355 set_cfun (new_cfun);
4358 /* Return value of funcdef and increase it. */
4360 get_next_funcdef_no (void)
4362 return funcdef_no++;
4365 /* Allocate a function structure for FNDECL and set its contents
4366 to the defaults. Set cfun to the newly-allocated object.
4367 Some of the helper functions invoked during initialization assume
4368 that cfun has already been set. Therefore, assign the new object
4369 directly into cfun and invoke the back end hook explicitly at the
4370 very end, rather than initializing a temporary and calling set_cfun
4373 ABSTRACT_P is true if this is a function that will never be seen by
4374 the middle-end. Such functions are front-end concepts (like C++
4375 function templates) that do not correspond directly to functions
4376 placed in object files. */
4379 allocate_struct_function (tree fndecl, bool abstract_p)
4382 tree fntype = fndecl ? TREE_TYPE (fndecl) : NULL_TREE;
4384 cfun = ggc_alloc_cleared_function ();
4386 init_eh_for_function ();
4388 if (init_machine_status)
4389 cfun->machine = (*init_machine_status) ();
4391 #ifdef OVERRIDE_ABI_FORMAT
4392 OVERRIDE_ABI_FORMAT (fndecl);
4395 invoke_set_current_function_hook (fndecl);
4397 if (fndecl != NULL_TREE)
4399 DECL_STRUCT_FUNCTION (fndecl) = cfun;
4400 cfun->decl = fndecl;
4401 current_function_funcdef_no = get_next_funcdef_no ();
4403 result = DECL_RESULT (fndecl);
4404 if (!abstract_p && aggregate_value_p (result, fndecl))
4406 #ifdef PCC_STATIC_STRUCT_RETURN
4407 cfun->returns_pcc_struct = 1;
4409 cfun->returns_struct = 1;
4412 cfun->stdarg = stdarg_p (fntype);
4414 /* Assume all registers in stdarg functions need to be saved. */
4415 cfun->va_list_gpr_size = VA_LIST_MAX_GPR_SIZE;
4416 cfun->va_list_fpr_size = VA_LIST_MAX_FPR_SIZE;
4418 /* ??? This could be set on a per-function basis by the front-end
4419 but is this worth the hassle? */
4420 cfun->can_throw_non_call_exceptions = flag_non_call_exceptions;
4424 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
4425 instead of just setting it. */
4428 push_struct_function (tree fndecl)
4430 VEC_safe_push (function_p, heap, cfun_stack, cfun);
4431 allocate_struct_function (fndecl, false);
4434 /* Reset crtl and other non-struct-function variables to defaults as
4435 appropriate for emitting rtl at the start of a function. */
4438 prepare_function_start (void)
4440 gcc_assert (!crtl->emit.x_last_insn);
4443 init_varasm_status ();
4445 default_rtl_profile ();
4447 if (flag_stack_usage)
4449 cfun->su = ggc_alloc_cleared_stack_usage ();
4450 cfun->su->static_stack_size = -1;
4453 cse_not_expected = ! optimize;
4455 /* Caller save not needed yet. */
4456 caller_save_needed = 0;
4458 /* We haven't done register allocation yet. */
4461 /* Indicate that we have not instantiated virtual registers yet. */
4462 virtuals_instantiated = 0;
4464 /* Indicate that we want CONCATs now. */
4465 generating_concat_p = 1;
4467 /* Indicate we have no need of a frame pointer yet. */
4468 frame_pointer_needed = 0;
4471 /* Initialize the rtl expansion mechanism so that we can do simple things
4472 like generate sequences. This is used to provide a context during global
4473 initialization of some passes. You must call expand_dummy_function_end
4474 to exit this context. */
4477 init_dummy_function_start (void)
4479 gcc_assert (!in_dummy_function);
4480 in_dummy_function = true;
4481 push_struct_function (NULL_TREE);
4482 prepare_function_start ();
4485 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
4486 and initialize static variables for generating RTL for the statements
4490 init_function_start (tree subr)
4492 if (subr && DECL_STRUCT_FUNCTION (subr))
4493 set_cfun (DECL_STRUCT_FUNCTION (subr));
4495 allocate_struct_function (subr, false);
4496 prepare_function_start ();
4498 /* Warn if this value is an aggregate type,
4499 regardless of which calling convention we are using for it. */
4500 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
4501 warning (OPT_Waggregate_return, "function returns an aggregate");
4504 /* Make sure all values used by the optimization passes have sane defaults. */
4506 init_function_for_compilation (void)
4512 struct rtl_opt_pass pass_init_function =
4516 "*init_function", /* name */
4518 init_function_for_compilation, /* execute */
4521 0, /* static_pass_number */
4522 TV_NONE, /* tv_id */
4523 0, /* properties_required */
4524 0, /* properties_provided */
4525 0, /* properties_destroyed */
4526 0, /* todo_flags_start */
4527 0 /* todo_flags_finish */
4533 expand_main_function (void)
4535 #if (defined(INVOKE__main) \
4536 || (!defined(HAS_INIT_SECTION) \
4537 && !defined(INIT_SECTION_ASM_OP) \
4538 && !defined(INIT_ARRAY_SECTION_ASM_OP)))
4539 emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0);
4543 /* Expand code to initialize the stack_protect_guard. This is invoked at
4544 the beginning of a function to be protected. */
4546 #ifndef HAVE_stack_protect_set
4547 # define HAVE_stack_protect_set 0
4548 # define gen_stack_protect_set(x,y) (gcc_unreachable (), NULL_RTX)
4552 stack_protect_prologue (void)
4554 tree guard_decl = targetm.stack_protect_guard ();
4557 x = expand_normal (crtl->stack_protect_guard);
4558 y = expand_normal (guard_decl);
4560 /* Allow the target to copy from Y to X without leaking Y into a
4562 if (HAVE_stack_protect_set)
4564 rtx insn = gen_stack_protect_set (x, y);
4572 /* Otherwise do a straight move. */
4573 emit_move_insn (x, y);
4576 /* Expand code to verify the stack_protect_guard. This is invoked at
4577 the end of a function to be protected. */
4579 #ifndef HAVE_stack_protect_test
4580 # define HAVE_stack_protect_test 0
4581 # define gen_stack_protect_test(x, y, z) (gcc_unreachable (), NULL_RTX)
4585 stack_protect_epilogue (void)
4587 tree guard_decl = targetm.stack_protect_guard ();
4588 rtx label = gen_label_rtx ();
4591 x = expand_normal (crtl->stack_protect_guard);
4592 y = expand_normal (guard_decl);
4594 /* Allow the target to compare Y with X without leaking either into
4596 switch (HAVE_stack_protect_test != 0)
4599 tmp = gen_stack_protect_test (x, y, label);
4608 emit_cmp_and_jump_insns (x, y, EQ, NULL_RTX, ptr_mode, 1, label);
4612 /* The noreturn predictor has been moved to the tree level. The rtl-level
4613 predictors estimate this branch about 20%, which isn't enough to get
4614 things moved out of line. Since this is the only extant case of adding
4615 a noreturn function at the rtl level, it doesn't seem worth doing ought
4616 except adding the prediction by hand. */
4617 tmp = get_last_insn ();
4619 predict_insn_def (tmp, PRED_NORETURN, TAKEN);
4621 expand_expr_stmt (targetm.stack_protect_fail ());
4625 /* Start the RTL for a new function, and set variables used for
4627 SUBR is the FUNCTION_DECL node.
4628 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4629 the function's parameters, which must be run at any return statement. */
4632 expand_function_start (tree subr)
4634 /* Make sure volatile mem refs aren't considered
4635 valid operands of arithmetic insns. */
4636 init_recog_no_volatile ();
4640 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
4643 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
4645 /* Make the label for return statements to jump to. Do not special
4646 case machines with special return instructions -- they will be
4647 handled later during jump, ifcvt, or epilogue creation. */
4648 return_label = gen_label_rtx ();
4650 /* Initialize rtx used to return the value. */
4651 /* Do this before assign_parms so that we copy the struct value address
4652 before any library calls that assign parms might generate. */
4654 /* Decide whether to return the value in memory or in a register. */
4655 if (aggregate_value_p (DECL_RESULT (subr), subr))
4657 /* Returning something that won't go in a register. */
4658 rtx value_address = 0;
4660 #ifdef PCC_STATIC_STRUCT_RETURN
4661 if (cfun->returns_pcc_struct)
4663 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
4664 value_address = assemble_static_space (size);
4669 rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 2);
4670 /* Expect to be passed the address of a place to store the value.
4671 If it is passed as an argument, assign_parms will take care of
4675 value_address = gen_reg_rtx (Pmode);
4676 emit_move_insn (value_address, sv);
4681 rtx x = value_address;
4682 if (!DECL_BY_REFERENCE (DECL_RESULT (subr)))
4684 x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), x);
4685 set_mem_attributes (x, DECL_RESULT (subr), 1);
4687 SET_DECL_RTL (DECL_RESULT (subr), x);
4690 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
4691 /* If return mode is void, this decl rtl should not be used. */
4692 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
4695 /* Compute the return values into a pseudo reg, which we will copy
4696 into the true return register after the cleanups are done. */
4697 tree return_type = TREE_TYPE (DECL_RESULT (subr));
4698 if (TYPE_MODE (return_type) != BLKmode
4699 && targetm.calls.return_in_msb (return_type))
4700 /* expand_function_end will insert the appropriate padding in
4701 this case. Use the return value's natural (unpadded) mode
4702 within the function proper. */
4703 SET_DECL_RTL (DECL_RESULT (subr),
4704 gen_reg_rtx (TYPE_MODE (return_type)));
4707 /* In order to figure out what mode to use for the pseudo, we
4708 figure out what the mode of the eventual return register will
4709 actually be, and use that. */
4710 rtx hard_reg = hard_function_value (return_type, subr, 0, 1);
4712 /* Structures that are returned in registers are not
4713 aggregate_value_p, so we may see a PARALLEL or a REG. */
4714 if (REG_P (hard_reg))
4715 SET_DECL_RTL (DECL_RESULT (subr),
4716 gen_reg_rtx (GET_MODE (hard_reg)));
4719 gcc_assert (GET_CODE (hard_reg) == PARALLEL);
4720 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
4724 /* Set DECL_REGISTER flag so that expand_function_end will copy the
4725 result to the real return register(s). */
4726 DECL_REGISTER (DECL_RESULT (subr)) = 1;
4729 /* Initialize rtx for parameters and local variables.
4730 In some cases this requires emitting insns. */
4731 assign_parms (subr);
4733 /* If function gets a static chain arg, store it. */
4734 if (cfun->static_chain_decl)
4736 tree parm = cfun->static_chain_decl;
4737 rtx local, chain, insn;
4739 local = gen_reg_rtx (Pmode);
4740 chain = targetm.calls.static_chain (current_function_decl, true);
4742 set_decl_incoming_rtl (parm, chain, false);
4743 SET_DECL_RTL (parm, local);
4744 mark_reg_pointer (local, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
4746 insn = emit_move_insn (local, chain);
4748 /* Mark the register as eliminable, similar to parameters. */
4750 && reg_mentioned_p (arg_pointer_rtx, XEXP (chain, 0)))
4751 set_unique_reg_note (insn, REG_EQUIV, chain);
4754 /* If the function receives a non-local goto, then store the
4755 bits we need to restore the frame pointer. */
4756 if (cfun->nonlocal_goto_save_area)
4761 /* ??? We need to do this save early. Unfortunately here is
4762 before the frame variable gets declared. Help out... */
4763 tree var = TREE_OPERAND (cfun->nonlocal_goto_save_area, 0);
4764 if (!DECL_RTL_SET_P (var))
4767 t_save = build4 (ARRAY_REF, ptr_type_node,
4768 cfun->nonlocal_goto_save_area,
4769 integer_zero_node, NULL_TREE, NULL_TREE);
4770 r_save = expand_expr (t_save, NULL_RTX, VOIDmode, EXPAND_WRITE);
4771 r_save = convert_memory_address (Pmode, r_save);
4773 emit_move_insn (r_save, targetm.builtin_setjmp_frame_value ());
4774 update_nonlocal_goto_save_area ();
4777 /* The following was moved from init_function_start.
4778 The move is supposed to make sdb output more accurate. */
4779 /* Indicate the beginning of the function body,
4780 as opposed to parm setup. */
4781 emit_note (NOTE_INSN_FUNCTION_BEG);
4783 gcc_assert (NOTE_P (get_last_insn ()));
4785 parm_birth_insn = get_last_insn ();
4790 PROFILE_HOOK (current_function_funcdef_no);
4794 /* After the display initializations is where the stack checking
4796 if(flag_stack_check)
4797 stack_check_probe_note = emit_note (NOTE_INSN_DELETED);
4799 /* Make sure there is a line number after the function entry setup code. */
4800 force_next_line_note ();
4803 /* Undo the effects of init_dummy_function_start. */
4805 expand_dummy_function_end (void)
4807 gcc_assert (in_dummy_function);
4809 /* End any sequences that failed to be closed due to syntax errors. */
4810 while (in_sequence_p ())
4813 /* Outside function body, can't compute type's actual size
4814 until next function's body starts. */
4816 free_after_parsing (cfun);
4817 free_after_compilation (cfun);
4819 in_dummy_function = false;
4822 /* Call DOIT for each hard register used as a return value from
4823 the current function. */
4826 diddle_return_value (void (*doit) (rtx, void *), void *arg)
4828 rtx outgoing = crtl->return_rtx;
4833 if (REG_P (outgoing))
4834 (*doit) (outgoing, arg);
4835 else if (GET_CODE (outgoing) == PARALLEL)
4839 for (i = 0; i < XVECLEN (outgoing, 0); i++)
4841 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
4843 if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER)
4850 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
4856 clobber_return_register (void)
4858 diddle_return_value (do_clobber_return_reg, NULL);
4860 /* In case we do use pseudo to return value, clobber it too. */
4861 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
4863 tree decl_result = DECL_RESULT (current_function_decl);
4864 rtx decl_rtl = DECL_RTL (decl_result);
4865 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
4867 do_clobber_return_reg (decl_rtl, NULL);
4873 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
4879 use_return_register (void)
4881 diddle_return_value (do_use_return_reg, NULL);
4884 /* Possibly warn about unused parameters. */
4886 do_warn_unused_parameter (tree fn)
4890 for (decl = DECL_ARGUMENTS (fn);
4891 decl; decl = DECL_CHAIN (decl))
4892 if (!TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
4893 && DECL_NAME (decl) && !DECL_ARTIFICIAL (decl)
4894 && !TREE_NO_WARNING (decl))
4895 warning (OPT_Wunused_parameter, "unused parameter %q+D", decl);
4898 static GTY(()) rtx initial_trampoline;
4900 /* Generate RTL for the end of the current function. */
4903 expand_function_end (void)
4907 /* If arg_pointer_save_area was referenced only from a nested
4908 function, we will not have initialized it yet. Do that now. */
4909 if (arg_pointer_save_area && ! crtl->arg_pointer_save_area_init)
4910 get_arg_pointer_save_area ();
4912 /* If we are doing generic stack checking and this function makes calls,
4913 do a stack probe at the start of the function to ensure we have enough
4914 space for another stack frame. */
4915 if (flag_stack_check == GENERIC_STACK_CHECK)
4919 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4922 rtx max_frame_size = GEN_INT (STACK_CHECK_MAX_FRAME_SIZE);
4924 if (STACK_CHECK_MOVING_SP)
4925 anti_adjust_stack_and_probe (max_frame_size, true);
4927 probe_stack_range (STACK_OLD_CHECK_PROTECT, max_frame_size);
4930 set_insn_locators (seq, prologue_locator);
4931 emit_insn_before (seq, stack_check_probe_note);
4936 /* End any sequences that failed to be closed due to syntax errors. */
4937 while (in_sequence_p ())
4940 clear_pending_stack_adjust ();
4941 do_pending_stack_adjust ();
4943 /* Output a linenumber for the end of the function.
4944 SDB depends on this. */
4945 force_next_line_note ();
4946 set_curr_insn_source_location (input_location);
4948 /* Before the return label (if any), clobber the return
4949 registers so that they are not propagated live to the rest of
4950 the function. This can only happen with functions that drop
4951 through; if there had been a return statement, there would
4952 have either been a return rtx, or a jump to the return label.
4954 We delay actual code generation after the current_function_value_rtx
4956 clobber_after = get_last_insn ();
4958 /* Output the label for the actual return from the function. */
4959 emit_label (return_label);
4961 if (targetm.except_unwind_info (&global_options) == UI_SJLJ)
4963 /* Let except.c know where it should emit the call to unregister
4964 the function context for sjlj exceptions. */
4965 if (flag_exceptions)
4966 sjlj_emit_function_exit_after (get_last_insn ());
4970 /* We want to ensure that instructions that may trap are not
4971 moved into the epilogue by scheduling, because we don't
4972 always emit unwind information for the epilogue. */
4973 if (cfun->can_throw_non_call_exceptions)
4974 emit_insn (gen_blockage ());
4977 /* If this is an implementation of throw, do what's necessary to
4978 communicate between __builtin_eh_return and the epilogue. */
4979 expand_eh_return ();
4981 /* If scalar return value was computed in a pseudo-reg, or was a named
4982 return value that got dumped to the stack, copy that to the hard
4984 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
4986 tree decl_result = DECL_RESULT (current_function_decl);
4987 rtx decl_rtl = DECL_RTL (decl_result);
4989 if (REG_P (decl_rtl)
4990 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
4991 : DECL_REGISTER (decl_result))
4993 rtx real_decl_rtl = crtl->return_rtx;
4995 /* This should be set in assign_parms. */
4996 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl));
4998 /* If this is a BLKmode structure being returned in registers,
4999 then use the mode computed in expand_return. Note that if
5000 decl_rtl is memory, then its mode may have been changed,
5001 but that crtl->return_rtx has not. */
5002 if (GET_MODE (real_decl_rtl) == BLKmode)
5003 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
5005 /* If a non-BLKmode return value should be padded at the least
5006 significant end of the register, shift it left by the appropriate
5007 amount. BLKmode results are handled using the group load/store
5009 if (TYPE_MODE (TREE_TYPE (decl_result)) != BLKmode
5010 && targetm.calls.return_in_msb (TREE_TYPE (decl_result)))
5012 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl),
5013 REGNO (real_decl_rtl)),
5015 shift_return_value (GET_MODE (decl_rtl), true, real_decl_rtl);
5017 /* If a named return value dumped decl_return to memory, then
5018 we may need to re-do the PROMOTE_MODE signed/unsigned
5020 else if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
5022 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (decl_result));
5023 promote_function_mode (TREE_TYPE (decl_result),
5024 GET_MODE (decl_rtl), &unsignedp,
5025 TREE_TYPE (current_function_decl), 1);
5027 convert_move (real_decl_rtl, decl_rtl, unsignedp);
5029 else if (GET_CODE (real_decl_rtl) == PARALLEL)
5031 /* If expand_function_start has created a PARALLEL for decl_rtl,
5032 move the result to the real return registers. Otherwise, do
5033 a group load from decl_rtl for a named return. */
5034 if (GET_CODE (decl_rtl) == PARALLEL)
5035 emit_group_move (real_decl_rtl, decl_rtl);
5037 emit_group_load (real_decl_rtl, decl_rtl,
5038 TREE_TYPE (decl_result),
5039 int_size_in_bytes (TREE_TYPE (decl_result)));
5041 /* In the case of complex integer modes smaller than a word, we'll
5042 need to generate some non-trivial bitfield insertions. Do that
5043 on a pseudo and not the hard register. */
5044 else if (GET_CODE (decl_rtl) == CONCAT
5045 && GET_MODE_CLASS (GET_MODE (decl_rtl)) == MODE_COMPLEX_INT
5046 && GET_MODE_BITSIZE (GET_MODE (decl_rtl)) <= BITS_PER_WORD)
5048 int old_generating_concat_p;
5051 old_generating_concat_p = generating_concat_p;
5052 generating_concat_p = 0;
5053 tmp = gen_reg_rtx (GET_MODE (decl_rtl));
5054 generating_concat_p = old_generating_concat_p;
5056 emit_move_insn (tmp, decl_rtl);
5057 emit_move_insn (real_decl_rtl, tmp);
5060 emit_move_insn (real_decl_rtl, decl_rtl);
5064 /* If returning a structure, arrange to return the address of the value
5065 in a place where debuggers expect to find it.
5067 If returning a structure PCC style,
5068 the caller also depends on this value.
5069 And cfun->returns_pcc_struct is not necessarily set. */
5070 if (cfun->returns_struct
5071 || cfun->returns_pcc_struct)
5073 rtx value_address = DECL_RTL (DECL_RESULT (current_function_decl));
5074 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
5077 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))
5078 type = TREE_TYPE (type);
5080 value_address = XEXP (value_address, 0);
5082 outgoing = targetm.calls.function_value (build_pointer_type (type),
5083 current_function_decl, true);
5085 /* Mark this as a function return value so integrate will delete the
5086 assignment and USE below when inlining this function. */
5087 REG_FUNCTION_VALUE_P (outgoing) = 1;
5089 /* The address may be ptr_mode and OUTGOING may be Pmode. */
5090 value_address = convert_memory_address (GET_MODE (outgoing),
5093 emit_move_insn (outgoing, value_address);
5095 /* Show return register used to hold result (in this case the address
5097 crtl->return_rtx = outgoing;
5100 /* Emit the actual code to clobber return register. */
5105 clobber_return_register ();
5109 emit_insn_after (seq, clobber_after);
5112 /* Output the label for the naked return from the function. */
5113 if (naked_return_label)
5114 emit_label (naked_return_label);
5116 /* @@@ This is a kludge. We want to ensure that instructions that
5117 may trap are not moved into the epilogue by scheduling, because
5118 we don't always emit unwind information for the epilogue. */
5119 if (cfun->can_throw_non_call_exceptions
5120 && targetm.except_unwind_info (&global_options) != UI_SJLJ)
5121 emit_insn (gen_blockage ());
5123 /* If stack protection is enabled for this function, check the guard. */
5124 if (crtl->stack_protect_guard)
5125 stack_protect_epilogue ();
5127 /* If we had calls to alloca, and this machine needs
5128 an accurate stack pointer to exit the function,
5129 insert some code to save and restore the stack pointer. */
5130 if (! EXIT_IGNORE_STACK
5131 && cfun->calls_alloca)
5136 emit_stack_save (SAVE_FUNCTION, &tem);
5139 emit_insn_before (seq, parm_birth_insn);
5141 emit_stack_restore (SAVE_FUNCTION, tem);
5144 /* ??? This should no longer be necessary since stupid is no longer with
5145 us, but there are some parts of the compiler (eg reload_combine, and
5146 sh mach_dep_reorg) that still try and compute their own lifetime info
5147 instead of using the general framework. */
5148 use_return_register ();
5152 get_arg_pointer_save_area (void)
5154 rtx ret = arg_pointer_save_area;
5158 ret = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
5159 arg_pointer_save_area = ret;
5162 if (! crtl->arg_pointer_save_area_init)
5166 /* Save the arg pointer at the beginning of the function. The
5167 generated stack slot may not be a valid memory address, so we
5168 have to check it and fix it if necessary. */
5170 emit_move_insn (validize_mem (ret),
5171 crtl->args.internal_arg_pointer);
5175 push_topmost_sequence ();
5176 emit_insn_after (seq, entry_of_function ());
5177 pop_topmost_sequence ();
5179 crtl->arg_pointer_save_area_init = true;
5185 /* Add a list of INSNS to the hash HASHP, possibly allocating HASHP
5186 for the first time. */
5189 record_insns (rtx insns, rtx end, htab_t *hashp)
5192 htab_t hash = *hashp;
5196 = htab_create_ggc (17, htab_hash_pointer, htab_eq_pointer, NULL);
5198 for (tmp = insns; tmp != end; tmp = NEXT_INSN (tmp))
5200 void **slot = htab_find_slot (hash, tmp, INSERT);
5201 gcc_assert (*slot == NULL);
5206 /* INSN has been duplicated or replaced by as COPY, perhaps by duplicating a
5207 basic block, splitting or peepholes. If INSN is a prologue or epilogue
5208 insn, then record COPY as well. */
5211 maybe_copy_prologue_epilogue_insn (rtx insn, rtx copy)
5216 hash = epilogue_insn_hash;
5217 if (!hash || !htab_find (hash, insn))
5219 hash = prologue_insn_hash;
5220 if (!hash || !htab_find (hash, insn))
5224 slot = htab_find_slot (hash, copy, INSERT);
5225 gcc_assert (*slot == NULL);
5229 /* Set the locator of the insn chain starting at INSN to LOC. */
5231 set_insn_locators (rtx insn, int loc)
5233 while (insn != NULL_RTX)
5236 INSN_LOCATOR (insn) = loc;
5237 insn = NEXT_INSN (insn);
5241 /* Determine if any INSNs in HASH are, or are part of, INSN. Because
5242 we can be running after reorg, SEQUENCE rtl is possible. */
5245 contains (const_rtx insn, htab_t hash)
5250 if (NONJUMP_INSN_P (insn) && GET_CODE (PATTERN (insn)) == SEQUENCE)
5253 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
5254 if (htab_find (hash, XVECEXP (PATTERN (insn), 0, i)))
5259 return htab_find (hash, insn) != NULL;
5263 prologue_epilogue_contains (const_rtx insn)
5265 if (contains (insn, prologue_insn_hash))
5267 if (contains (insn, epilogue_insn_hash))
5273 /* Insert gen_return at the end of block BB. This also means updating
5274 block_for_insn appropriately. */
5277 emit_return_into_block (basic_block bb)
5279 emit_jump_insn_after (gen_return (), BB_END (bb));
5281 #endif /* HAVE_return */
5283 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
5284 this into place with notes indicating where the prologue ends and where
5285 the epilogue begins. Update the basic block information when possible. */
5288 thread_prologue_and_epilogue_insns (void)
5291 rtx seq ATTRIBUTE_UNUSED, epilogue_end ATTRIBUTE_UNUSED;
5292 edge entry_edge ATTRIBUTE_UNUSED;
5296 rtl_profile_for_bb (ENTRY_BLOCK_PTR);
5300 epilogue_end = NULL_RTX;
5302 /* Can't deal with multiple successors of the entry block at the
5303 moment. Function should always have at least one entry
5305 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR));
5306 entry_edge = single_succ_edge (ENTRY_BLOCK_PTR);
5308 if (flag_split_stack
5309 && (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (cfun->decl))
5312 #ifndef HAVE_split_stack_prologue
5315 gcc_assert (HAVE_split_stack_prologue);
5318 emit_insn (gen_split_stack_prologue ());
5322 record_insns (seq, NULL, &prologue_insn_hash);
5323 set_insn_locators (seq, prologue_locator);
5325 /* This relies on the fact that committing the edge insertion
5326 will look for basic blocks within the inserted instructions,
5327 which in turn relies on the fact that we are not in CFG
5328 layout mode here. */
5329 insert_insn_on_edge (seq, entry_edge);
5334 #ifdef HAVE_prologue
5338 seq = gen_prologue ();
5341 /* Insert an explicit USE for the frame pointer
5342 if the profiling is on and the frame pointer is required. */
5343 if (crtl->profile && frame_pointer_needed)
5344 emit_use (hard_frame_pointer_rtx);
5346 /* Retain a map of the prologue insns. */
5347 record_insns (seq, NULL, &prologue_insn_hash);
5348 emit_note (NOTE_INSN_PROLOGUE_END);
5350 /* Ensure that instructions are not moved into the prologue when
5351 profiling is on. The call to the profiling routine can be
5352 emitted within the live range of a call-clobbered register. */
5353 if (!targetm.profile_before_prologue () && crtl->profile)
5354 emit_insn (gen_blockage ());
5358 set_insn_locators (seq, prologue_locator);
5360 insert_insn_on_edge (seq, entry_edge);
5365 /* If the exit block has no non-fake predecessors, we don't need
5367 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5368 if ((e->flags & EDGE_FAKE) == 0)
5373 rtl_profile_for_bb (EXIT_BLOCK_PTR);
5375 if (optimize && HAVE_return)
5377 /* If we're allowed to generate a simple return instruction,
5378 then by definition we don't need a full epilogue. Examine
5379 the block that falls through to EXIT. If it does not
5380 contain any code, examine its predecessors and try to
5381 emit (conditional) return instructions. */
5386 e = find_fallthru_edge (EXIT_BLOCK_PTR->preds);
5391 /* Verify that there are no active instructions in the last block. */
5392 label = BB_END (last);
5393 while (label && !LABEL_P (label))
5395 if (active_insn_p (label))
5397 label = PREV_INSN (label);
5400 if (BB_HEAD (last) == label && LABEL_P (label))
5404 for (ei2 = ei_start (last->preds); (e = ei_safe_edge (ei2)); )
5406 basic_block bb = e->src;
5409 if (bb == ENTRY_BLOCK_PTR)
5416 if (!JUMP_P (jump) || JUMP_LABEL (jump) != label)
5422 /* If we have an unconditional jump, we can replace that
5423 with a simple return instruction. */
5424 if (simplejump_p (jump))
5426 emit_return_into_block (bb);
5430 /* If we have a conditional jump, we can try to replace
5431 that with a conditional return instruction. */
5432 else if (condjump_p (jump))
5434 if (! redirect_jump (jump, 0, 0))
5440 /* If this block has only one successor, it both jumps
5441 and falls through to the fallthru block, so we can't
5443 if (single_succ_p (bb))
5455 /* Fix up the CFG for the successful change we just made. */
5456 redirect_edge_succ (e, EXIT_BLOCK_PTR);
5459 /* Emit a return insn for the exit fallthru block. Whether
5460 this is still reachable will be determined later. */
5462 emit_barrier_after (BB_END (last));
5463 emit_return_into_block (last);
5464 epilogue_end = BB_END (last);
5465 single_succ_edge (last)->flags &= ~EDGE_FALLTHRU;
5471 /* A small fib -- epilogue is not yet completed, but we wish to re-use
5472 this marker for the splits of EH_RETURN patterns, and nothing else
5473 uses the flag in the meantime. */
5474 epilogue_completed = 1;
5476 #ifdef HAVE_eh_return
5477 /* Find non-fallthru edges that end with EH_RETURN instructions. On
5478 some targets, these get split to a special version of the epilogue
5479 code. In order to be able to properly annotate these with unwind
5480 info, try to split them now. If we get a valid split, drop an
5481 EPILOGUE_BEG note and mark the insns as epilogue insns. */
5482 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5484 rtx prev, last, trial;
5486 if (e->flags & EDGE_FALLTHRU)
5488 last = BB_END (e->src);
5489 if (!eh_returnjump_p (last))
5492 prev = PREV_INSN (last);
5493 trial = try_split (PATTERN (last), last, 1);
5497 record_insns (NEXT_INSN (prev), NEXT_INSN (trial), &epilogue_insn_hash);
5498 emit_note_after (NOTE_INSN_EPILOGUE_BEG, prev);
5502 /* Find the edge that falls through to EXIT. Other edges may exist
5503 due to RETURN instructions, but those don't need epilogues.
5504 There really shouldn't be a mixture -- either all should have
5505 been converted or none, however... */
5507 e = find_fallthru_edge (EXIT_BLOCK_PTR->preds);
5511 #ifdef HAVE_epilogue
5515 epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG);
5516 seq = gen_epilogue ();
5518 emit_jump_insn (seq);
5520 /* Retain a map of the epilogue insns. */
5521 record_insns (seq, NULL, &epilogue_insn_hash);
5522 set_insn_locators (seq, epilogue_locator);
5527 insert_insn_on_edge (seq, e);
5535 if (! next_active_insn (BB_END (e->src)))
5537 /* We have a fall-through edge to the exit block, the source is not
5538 at the end of the function, and there will be an assembler epilogue
5539 at the end of the function.
5540 We can't use force_nonfallthru here, because that would try to
5541 use return. Inserting a jump 'by hand' is extremely messy, so
5542 we take advantage of cfg_layout_finalize using
5543 fixup_fallthru_exit_predecessor. */
5544 cfg_layout_initialize (0);
5545 FOR_EACH_BB (cur_bb)
5546 if (cur_bb->index >= NUM_FIXED_BLOCKS
5547 && cur_bb->next_bb->index >= NUM_FIXED_BLOCKS)
5548 cur_bb->aux = cur_bb->next_bb;
5549 cfg_layout_finalize ();
5552 default_rtl_profile ();
5556 commit_edge_insertions ();
5558 /* The epilogue insns we inserted may cause the exit edge to no longer
5560 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5562 if (((e->flags & EDGE_FALLTHRU) != 0)
5563 && returnjump_p (BB_END (e->src)))
5564 e->flags &= ~EDGE_FALLTHRU;
5568 #ifdef HAVE_sibcall_epilogue
5569 /* Emit sibling epilogues before any sibling call sites. */
5570 for (ei = ei_start (EXIT_BLOCK_PTR->preds); (e = ei_safe_edge (ei)); )
5572 basic_block bb = e->src;
5573 rtx insn = BB_END (bb);
5576 || ! SIBLING_CALL_P (insn))
5583 emit_note (NOTE_INSN_EPILOGUE_BEG);
5584 emit_insn (gen_sibcall_epilogue ());
5588 /* Retain a map of the epilogue insns. Used in life analysis to
5589 avoid getting rid of sibcall epilogue insns. Do this before we
5590 actually emit the sequence. */
5591 record_insns (seq, NULL, &epilogue_insn_hash);
5592 set_insn_locators (seq, epilogue_locator);
5594 emit_insn_before (seq, insn);
5599 #ifdef HAVE_epilogue
5604 /* Similarly, move any line notes that appear after the epilogue.
5605 There is no need, however, to be quite so anal about the existence
5606 of such a note. Also possibly move
5607 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
5609 for (insn = epilogue_end; insn; insn = next)
5611 next = NEXT_INSN (insn);
5613 && (NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG))
5614 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
5619 /* Threading the prologue and epilogue changes the artificial refs
5620 in the entry and exit blocks. */
5621 epilogue_completed = 1;
5622 df_update_entry_exit_and_calls ();
5625 /* Reposition the prologue-end and epilogue-begin notes after
5626 instruction scheduling. */
5629 reposition_prologue_and_epilogue_notes (void)
5631 #if defined (HAVE_prologue) || defined (HAVE_epilogue) \
5632 || defined (HAVE_sibcall_epilogue)
5633 /* Since the hash table is created on demand, the fact that it is
5634 non-null is a signal that it is non-empty. */
5635 if (prologue_insn_hash != NULL)
5637 size_t len = htab_elements (prologue_insn_hash);
5638 rtx insn, last = NULL, note = NULL;
5640 /* Scan from the beginning until we reach the last prologue insn. */
5641 /* ??? While we do have the CFG intact, there are two problems:
5642 (1) The prologue can contain loops (typically probing the stack),
5643 which means that the end of the prologue isn't in the first bb.
5644 (2) Sometimes the PROLOGUE_END note gets pushed into the next bb. */
5645 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
5649 if (NOTE_KIND (insn) == NOTE_INSN_PROLOGUE_END)
5652 else if (contains (insn, prologue_insn_hash))
5664 /* Scan forward looking for the PROLOGUE_END note. It should
5665 be right at the beginning of the block, possibly with other
5666 insn notes that got moved there. */
5667 for (note = NEXT_INSN (last); ; note = NEXT_INSN (note))
5670 && NOTE_KIND (note) == NOTE_INSN_PROLOGUE_END)
5675 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
5677 last = NEXT_INSN (last);
5678 reorder_insns (note, note, last);
5682 if (epilogue_insn_hash != NULL)
5687 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5689 rtx insn, first = NULL, note = NULL;
5690 basic_block bb = e->src;
5692 /* Scan from the beginning until we reach the first epilogue insn. */
5693 FOR_BB_INSNS (bb, insn)
5697 if (NOTE_KIND (insn) == NOTE_INSN_EPILOGUE_BEG)
5704 else if (first == NULL && contains (insn, epilogue_insn_hash))
5714 /* If the function has a single basic block, and no real
5715 epilogue insns (e.g. sibcall with no cleanup), the
5716 epilogue note can get scheduled before the prologue
5717 note. If we have frame related prologue insns, having
5718 them scanned during the epilogue will result in a crash.
5719 In this case re-order the epilogue note to just before
5720 the last insn in the block. */
5722 first = BB_END (bb);
5724 if (PREV_INSN (first) != note)
5725 reorder_insns (note, note, PREV_INSN (first));
5729 #endif /* HAVE_prologue or HAVE_epilogue */
5732 /* Returns the name of the current function. */
5734 current_function_name (void)
5738 return lang_hooks.decl_printable_name (cfun->decl, 2);
5743 rest_of_handle_check_leaf_regs (void)
5745 #ifdef LEAF_REGISTERS
5746 current_function_uses_only_leaf_regs
5747 = optimize > 0 && only_leaf_regs_used () && leaf_function_p ();
5752 /* Insert a TYPE into the used types hash table of CFUN. */
5755 used_types_insert_helper (tree type, struct function *func)
5757 if (type != NULL && func != NULL)
5761 if (func->used_types_hash == NULL)
5762 func->used_types_hash = htab_create_ggc (37, htab_hash_pointer,
5763 htab_eq_pointer, NULL);
5764 slot = htab_find_slot (func->used_types_hash, type, INSERT);
5770 /* Given a type, insert it into the used hash table in cfun. */
5772 used_types_insert (tree t)
5774 while (POINTER_TYPE_P (t) || TREE_CODE (t) == ARRAY_TYPE)
5779 if (TREE_CODE (t) == ERROR_MARK)
5781 if (TYPE_NAME (t) == NULL_TREE
5782 || TYPE_NAME (t) == TYPE_NAME (TYPE_MAIN_VARIANT (t)))
5783 t = TYPE_MAIN_VARIANT (t);
5784 if (debug_info_level > DINFO_LEVEL_NONE)
5787 used_types_insert_helper (t, cfun);
5789 /* So this might be a type referenced by a global variable.
5790 Record that type so that we can later decide to emit its debug
5792 VEC_safe_push (tree, gc, types_used_by_cur_var_decl, t);
5796 /* Helper to Hash a struct types_used_by_vars_entry. */
5799 hash_types_used_by_vars_entry (const struct types_used_by_vars_entry *entry)
5801 gcc_assert (entry && entry->var_decl && entry->type);
5803 return iterative_hash_object (entry->type,
5804 iterative_hash_object (entry->var_decl, 0));
5807 /* Hash function of the types_used_by_vars_entry hash table. */
5810 types_used_by_vars_do_hash (const void *x)
5812 const struct types_used_by_vars_entry *entry =
5813 (const struct types_used_by_vars_entry *) x;
5815 return hash_types_used_by_vars_entry (entry);
5818 /*Equality function of the types_used_by_vars_entry hash table. */
5821 types_used_by_vars_eq (const void *x1, const void *x2)
5823 const struct types_used_by_vars_entry *e1 =
5824 (const struct types_used_by_vars_entry *) x1;
5825 const struct types_used_by_vars_entry *e2 =
5826 (const struct types_used_by_vars_entry *)x2;
5828 return (e1->var_decl == e2->var_decl && e1->type == e2->type);
5831 /* Inserts an entry into the types_used_by_vars_hash hash table. */
5834 types_used_by_var_decl_insert (tree type, tree var_decl)
5836 if (type != NULL && var_decl != NULL)
5839 struct types_used_by_vars_entry e;
5840 e.var_decl = var_decl;
5842 if (types_used_by_vars_hash == NULL)
5843 types_used_by_vars_hash =
5844 htab_create_ggc (37, types_used_by_vars_do_hash,
5845 types_used_by_vars_eq, NULL);
5846 slot = htab_find_slot_with_hash (types_used_by_vars_hash, &e,
5847 hash_types_used_by_vars_entry (&e), INSERT);
5850 struct types_used_by_vars_entry *entry;
5851 entry = ggc_alloc_types_used_by_vars_entry ();
5853 entry->var_decl = var_decl;
5859 struct rtl_opt_pass pass_leaf_regs =
5863 "*leaf_regs", /* name */
5865 rest_of_handle_check_leaf_regs, /* execute */
5868 0, /* static_pass_number */
5869 TV_NONE, /* tv_id */
5870 0, /* properties_required */
5871 0, /* properties_provided */
5872 0, /* properties_destroyed */
5873 0, /* todo_flags_start */
5874 0 /* todo_flags_finish */
5879 rest_of_handle_thread_prologue_and_epilogue (void)
5882 cleanup_cfg (CLEANUP_EXPENSIVE);
5884 /* On some machines, the prologue and epilogue code, or parts thereof,
5885 can be represented as RTL. Doing so lets us schedule insns between
5886 it and the rest of the code and also allows delayed branch
5887 scheduling to operate in the epilogue. */
5888 thread_prologue_and_epilogue_insns ();
5890 /* The stack usage info is finalized during prologue expansion. */
5891 if (flag_stack_usage)
5892 output_stack_usage ();
5897 struct rtl_opt_pass pass_thread_prologue_and_epilogue =
5901 "pro_and_epilogue", /* name */
5903 rest_of_handle_thread_prologue_and_epilogue, /* execute */
5906 0, /* static_pass_number */
5907 TV_THREAD_PROLOGUE_AND_EPILOGUE, /* tv_id */
5908 0, /* properties_required */
5909 0, /* properties_provided */
5910 0, /* properties_destroyed */
5911 TODO_verify_flow, /* todo_flags_start */
5914 TODO_df_finish | TODO_verify_rtl_sharing |
5915 TODO_ggc_collect /* todo_flags_finish */
5920 /* This mini-pass fixes fall-out from SSA in asm statements that have
5921 in-out constraints. Say you start with
5924 asm ("": "+mr" (inout));
5927 which is transformed very early to use explicit output and match operands:
5930 asm ("": "=mr" (inout) : "0" (inout));
5933 Or, after SSA and copyprop,
5935 asm ("": "=mr" (inout_2) : "0" (inout_1));
5938 Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
5939 they represent two separate values, so they will get different pseudo
5940 registers during expansion. Then, since the two operands need to match
5941 per the constraints, but use different pseudo registers, reload can
5942 only register a reload for these operands. But reloads can only be
5943 satisfied by hardregs, not by memory, so we need a register for this
5944 reload, just because we are presented with non-matching operands.
5945 So, even though we allow memory for this operand, no memory can be
5946 used for it, just because the two operands don't match. This can
5947 cause reload failures on register-starved targets.
5949 So it's a symptom of reload not being able to use memory for reloads
5950 or, alternatively it's also a symptom of both operands not coming into
5951 reload as matching (in which case the pseudo could go to memory just
5952 fine, as the alternative allows it, and no reload would be necessary).
5953 We fix the latter problem here, by transforming
5955 asm ("": "=mr" (inout_2) : "0" (inout_1));
5960 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
5963 match_asm_constraints_1 (rtx insn, rtx *p_sets, int noutputs)
5966 bool changed = false;
5967 rtx op = SET_SRC (p_sets[0]);
5968 int ninputs = ASM_OPERANDS_INPUT_LENGTH (op);
5969 rtvec inputs = ASM_OPERANDS_INPUT_VEC (op);
5970 bool *output_matched = XALLOCAVEC (bool, noutputs);
5972 memset (output_matched, 0, noutputs * sizeof (bool));
5973 for (i = 0; i < ninputs; i++)
5975 rtx input, output, insns;
5976 const char *constraint = ASM_OPERANDS_INPUT_CONSTRAINT (op, i);
5980 if (*constraint == '%')
5983 match = strtoul (constraint, &end, 10);
5984 if (end == constraint)
5987 gcc_assert (match < noutputs);
5988 output = SET_DEST (p_sets[match]);
5989 input = RTVEC_ELT (inputs, i);
5990 /* Only do the transformation for pseudos. */
5991 if (! REG_P (output)
5992 || rtx_equal_p (output, input)
5993 || (GET_MODE (input) != VOIDmode
5994 && GET_MODE (input) != GET_MODE (output)))
5997 /* We can't do anything if the output is also used as input,
5998 as we're going to overwrite it. */
5999 for (j = 0; j < ninputs; j++)
6000 if (reg_overlap_mentioned_p (output, RTVEC_ELT (inputs, j)))
6005 /* Avoid changing the same input several times. For
6006 asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
6007 only change in once (to out1), rather than changing it
6008 first to out1 and afterwards to out2. */
6011 for (j = 0; j < noutputs; j++)
6012 if (output_matched[j] && input == SET_DEST (p_sets[j]))
6017 output_matched[match] = true;
6020 emit_move_insn (output, input);
6021 insns = get_insns ();
6023 emit_insn_before (insns, insn);
6025 /* Now replace all mentions of the input with output. We can't
6026 just replace the occurrence in inputs[i], as the register might
6027 also be used in some other input (or even in an address of an
6028 output), which would mean possibly increasing the number of
6029 inputs by one (namely 'output' in addition), which might pose
6030 a too complicated problem for reload to solve. E.g. this situation:
6032 asm ("" : "=r" (output), "=m" (input) : "0" (input))
6034 Here 'input' is used in two occurrences as input (once for the
6035 input operand, once for the address in the second output operand).
6036 If we would replace only the occurrence of the input operand (to
6037 make the matching) we would be left with this:
6040 asm ("" : "=r" (output), "=m" (input) : "0" (output))
6042 Now we suddenly have two different input values (containing the same
6043 value, but different pseudos) where we formerly had only one.
6044 With more complicated asms this might lead to reload failures
6045 which wouldn't have happen without this pass. So, iterate over
6046 all operands and replace all occurrences of the register used. */
6047 for (j = 0; j < noutputs; j++)
6048 if (!rtx_equal_p (SET_DEST (p_sets[j]), input)
6049 && reg_overlap_mentioned_p (input, SET_DEST (p_sets[j])))
6050 SET_DEST (p_sets[j]) = replace_rtx (SET_DEST (p_sets[j]),
6052 for (j = 0; j < ninputs; j++)
6053 if (reg_overlap_mentioned_p (input, RTVEC_ELT (inputs, j)))
6054 RTVEC_ELT (inputs, j) = replace_rtx (RTVEC_ELT (inputs, j),
6061 df_insn_rescan (insn);
6065 rest_of_match_asm_constraints (void)
6068 rtx insn, pat, *p_sets;
6071 if (!crtl->has_asm_statement)
6074 df_set_flags (DF_DEFER_INSN_RESCAN);
6077 FOR_BB_INSNS (bb, insn)
6082 pat = PATTERN (insn);
6083 if (GET_CODE (pat) == PARALLEL)
6084 p_sets = &XVECEXP (pat, 0, 0), noutputs = XVECLEN (pat, 0);
6085 else if (GET_CODE (pat) == SET)
6086 p_sets = &PATTERN (insn), noutputs = 1;
6090 if (GET_CODE (*p_sets) == SET
6091 && GET_CODE (SET_SRC (*p_sets)) == ASM_OPERANDS)
6092 match_asm_constraints_1 (insn, p_sets, noutputs);
6096 return TODO_df_finish;
6099 struct rtl_opt_pass pass_match_asm_constraints =
6103 "asmcons", /* name */
6105 rest_of_match_asm_constraints, /* execute */
6108 0, /* static_pass_number */
6109 TV_NONE, /* tv_id */
6110 0, /* properties_required */
6111 0, /* properties_provided */
6112 0, /* properties_destroyed */
6113 0, /* todo_flags_start */
6114 TODO_dump_func /* todo_flags_finish */
6119 #include "gt-function.h"