2010-07-22 Andi Kleen <ak@linux.intel.com>
[official-gcc.git] / gcc / function.c
blob5a308f445055ecbd2169214617ce8a985eaee3da
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 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
11 version.
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
16 for more details.
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. */
36 #include "config.h"
37 #include "system.h"
38 #include "coretypes.h"
39 #include "tm.h"
40 #include "rtl-error.h"
41 #include "tree.h"
42 #include "flags.h"
43 #include "except.h"
44 #include "function.h"
45 #include "expr.h"
46 #include "optabs.h"
47 #include "libfuncs.h"
48 #include "regs.h"
49 #include "hard-reg-set.h"
50 #include "insn-config.h"
51 #include "recog.h"
52 #include "output.h"
53 #include "basic-block.h"
54 #include "hashtab.h"
55 #include "ggc.h"
56 #include "tm_p.h"
57 #include "integrate.h"
58 #include "langhooks.h"
59 #include "target.h"
60 #include "cfglayout.h"
61 #include "gimple.h"
62 #include "tree-pass.h"
63 #include "predict.h"
64 #include "df.h"
65 #include "timevar.h"
66 #include "vecprim.h"
68 /* So we can assign to cfun in this file. */
69 #undef cfun
71 #ifndef STACK_ALIGNMENT_NEEDED
72 #define STACK_ALIGNMENT_NEEDED 1
73 #endif
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. */
81 #ifndef NAME__MAIN
82 #define NAME__MAIN "__main"
83 #endif
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
91 alignment. */
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
97 compiler passes. */
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);
149 #ifdef HAVE_return
150 static void emit_return_into_block (basic_block);
151 #endif
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. */
169 void
170 push_function_context (void)
172 if (cfun == 0)
173 allocate_struct_function (NULL, false);
175 VEC_safe_push (function_p, heap, function_context_stack, cfun);
176 set_cfun (NULL);
179 /* Restore the last saved context, at the end of a nested function.
180 This function is called from language-specific code. */
182 void
183 pop_function_context (void)
185 struct function *p = VEC_pop (function_p, function_context_stack);
186 set_cfun (p);
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. */
198 void
199 free_after_parsing (struct function *f)
201 f->language = 0;
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. */
208 void
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));
218 f->eh = NULL;
219 f->machine = NULL;
220 f->cfg = NULL;
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. */
230 HOST_WIDE_INT
231 get_frame_size (void)
233 if (FRAME_GROWS_DOWNWARD)
234 return -frame_offset;
235 else
236 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
241 return FALSE. */
243 bool
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");
254 return TRUE;
257 return FALSE;
260 /* Return stack slot alignment in bits for TYPE and MODE. */
262 static unsigned int
263 get_stack_local_alignment (tree type, enum machine_mode mode)
265 unsigned int alignment;
267 if (mode == BLKmode)
268 alignment = BIGGEST_ALIGNMENT;
269 else
270 alignment = GET_MODE_ALIGNMENT (mode);
272 /* Allow the frond-end to (possibly) increase the alignment of this
273 stack slot. */
274 if (! type)
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. */
287 static bool
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
296 stack alignment. */
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)
308 this_frame_offset
309 = (FLOOR_ROUND (start + length - size - frame_phase,
310 (unsigned HOST_WIDE_INT) alignment)
311 + frame_phase);
312 else
313 this_frame_offset
314 = (CEIL_ROUND (start - frame_phase,
315 (unsigned HOST_WIDE_INT) alignment)
316 + frame_phase);
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)
324 return false;
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)
329 return false;
331 *poffset = this_frame_offset;
332 return true;
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. */
339 static void
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 If REDUCE_ALIGNMENT_OK is true, it is OK to reduce alignment.
360 We do not round to stack_boundary here. */
363 assign_stack_local_1 (enum machine_mode mode, HOST_WIDE_INT size,
364 int align,
365 bool reduce_alignment_ok ATTRIBUTE_UNUSED)
367 rtx x, addr;
368 int bigend_correction = 0;
369 HOST_WIDE_INT slot_offset = 0, old_frame_offset;
370 unsigned int alignment, alignment_in_bits;
372 if (align == 0)
374 alignment = get_stack_local_alignment (NULL, mode);
375 alignment /= BITS_PER_UNIT;
377 else if (align == -1)
379 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
380 size = CEIL_ROUND (size, alignment);
382 else if (align == -2)
383 alignment = 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
384 else
385 alignment = align / BITS_PER_UNIT;
387 alignment_in_bits = alignment * BITS_PER_UNIT;
389 /* Ignore alignment if it exceeds MAX_SUPPORTED_STACK_ALIGNMENT. */
390 if (alignment_in_bits > MAX_SUPPORTED_STACK_ALIGNMENT)
392 alignment_in_bits = MAX_SUPPORTED_STACK_ALIGNMENT;
393 alignment = alignment_in_bits / BITS_PER_UNIT;
396 if (SUPPORTS_STACK_ALIGNMENT)
398 if (crtl->stack_alignment_estimated < alignment_in_bits)
400 if (!crtl->stack_realign_processed)
401 crtl->stack_alignment_estimated = alignment_in_bits;
402 else
404 /* If stack is realigned and stack alignment value
405 hasn't been finalized, it is OK not to increase
406 stack_alignment_estimated. The bigger alignment
407 requirement is recorded in stack_alignment_needed
408 below. */
409 gcc_assert (!crtl->stack_realign_finalized);
410 if (!crtl->stack_realign_needed)
412 /* It is OK to reduce the alignment as long as the
413 requested size is 0 or the estimated stack
414 alignment >= mode alignment. */
415 gcc_assert (reduce_alignment_ok
416 || size == 0
417 || (crtl->stack_alignment_estimated
418 >= GET_MODE_ALIGNMENT (mode)));
419 alignment_in_bits = crtl->stack_alignment_estimated;
420 alignment = alignment_in_bits / BITS_PER_UNIT;
426 if (crtl->stack_alignment_needed < alignment_in_bits)
427 crtl->stack_alignment_needed = alignment_in_bits;
428 if (crtl->max_used_stack_slot_alignment < alignment_in_bits)
429 crtl->max_used_stack_slot_alignment = alignment_in_bits;
431 if (mode != BLKmode || size != 0)
433 struct frame_space **psp;
435 for (psp = &crtl->frame_space_list; *psp; psp = &(*psp)->next)
437 struct frame_space *space = *psp;
438 if (!try_fit_stack_local (space->start, space->length, size,
439 alignment, &slot_offset))
440 continue;
441 *psp = space->next;
442 if (slot_offset > space->start)
443 add_frame_space (space->start, slot_offset);
444 if (slot_offset + size < space->start + space->length)
445 add_frame_space (slot_offset + size,
446 space->start + space->length);
447 goto found_space;
450 else if (!STACK_ALIGNMENT_NEEDED)
452 slot_offset = frame_offset;
453 goto found_space;
456 old_frame_offset = frame_offset;
458 if (FRAME_GROWS_DOWNWARD)
460 frame_offset -= size;
461 try_fit_stack_local (frame_offset, size, size, alignment, &slot_offset);
463 if (slot_offset > frame_offset)
464 add_frame_space (frame_offset, slot_offset);
465 if (slot_offset + size < old_frame_offset)
466 add_frame_space (slot_offset + size, old_frame_offset);
468 else
470 frame_offset += size;
471 try_fit_stack_local (old_frame_offset, size, size, alignment, &slot_offset);
473 if (slot_offset > old_frame_offset)
474 add_frame_space (old_frame_offset, slot_offset);
475 if (slot_offset + size < frame_offset)
476 add_frame_space (slot_offset + size, frame_offset);
479 found_space:
480 /* On a big-endian machine, if we are allocating more space than we will use,
481 use the least significant bytes of those that are allocated. */
482 if (BYTES_BIG_ENDIAN && mode != BLKmode && GET_MODE_SIZE (mode) < size)
483 bigend_correction = size - GET_MODE_SIZE (mode);
485 /* If we have already instantiated virtual registers, return the actual
486 address relative to the frame pointer. */
487 if (virtuals_instantiated)
488 addr = plus_constant (frame_pointer_rtx,
489 trunc_int_for_mode
490 (slot_offset + bigend_correction
491 + STARTING_FRAME_OFFSET, Pmode));
492 else
493 addr = plus_constant (virtual_stack_vars_rtx,
494 trunc_int_for_mode
495 (slot_offset + bigend_correction,
496 Pmode));
498 x = gen_rtx_MEM (mode, addr);
499 set_mem_align (x, alignment_in_bits);
500 MEM_NOTRAP_P (x) = 1;
502 stack_slot_list
503 = gen_rtx_EXPR_LIST (VOIDmode, x, stack_slot_list);
505 if (frame_offset_overflow (frame_offset, current_function_decl))
506 frame_offset = 0;
508 return x;
511 /* Wrap up assign_stack_local_1 with last parameter as false. */
514 assign_stack_local (enum machine_mode mode, HOST_WIDE_INT size, int align)
516 return assign_stack_local_1 (mode, size, align, false);
520 /* In order to evaluate some expressions, such as function calls returning
521 structures in memory, we need to temporarily allocate stack locations.
522 We record each allocated temporary in the following structure.
524 Associated with each temporary slot is a nesting level. When we pop up
525 one level, all temporaries associated with the previous level are freed.
526 Normally, all temporaries are freed after the execution of the statement
527 in which they were created. However, if we are inside a ({...}) grouping,
528 the result may be in a temporary and hence must be preserved. If the
529 result could be in a temporary, we preserve it if we can determine which
530 one it is in. If we cannot determine which temporary may contain the
531 result, all temporaries are preserved. A temporary is preserved by
532 pretending it was allocated at the previous nesting level.
534 Automatic variables are also assigned temporary slots, at the nesting
535 level where they are defined. They are marked a "kept" so that
536 free_temp_slots will not free them. */
538 struct GTY(()) temp_slot {
539 /* Points to next temporary slot. */
540 struct temp_slot *next;
541 /* Points to previous temporary slot. */
542 struct temp_slot *prev;
543 /* The rtx to used to reference the slot. */
544 rtx slot;
545 /* The size, in units, of the slot. */
546 HOST_WIDE_INT size;
547 /* The type of the object in the slot, or zero if it doesn't correspond
548 to a type. We use this to determine whether a slot can be reused.
549 It can be reused if objects of the type of the new slot will always
550 conflict with objects of the type of the old slot. */
551 tree type;
552 /* The alignment (in bits) of the slot. */
553 unsigned int align;
554 /* Nonzero if this temporary is currently in use. */
555 char in_use;
556 /* Nonzero if this temporary has its address taken. */
557 char addr_taken;
558 /* Nesting level at which this slot is being used. */
559 int level;
560 /* Nonzero if this should survive a call to free_temp_slots. */
561 int keep;
562 /* The offset of the slot from the frame_pointer, including extra space
563 for alignment. This info is for combine_temp_slots. */
564 HOST_WIDE_INT base_offset;
565 /* The size of the slot, including extra space for alignment. This
566 info is for combine_temp_slots. */
567 HOST_WIDE_INT full_size;
570 /* A table of addresses that represent a stack slot. The table is a mapping
571 from address RTXen to a temp slot. */
572 static GTY((param_is(struct temp_slot_address_entry))) htab_t temp_slot_address_table;
574 /* Entry for the above hash table. */
575 struct GTY(()) temp_slot_address_entry {
576 hashval_t hash;
577 rtx address;
578 struct temp_slot *temp_slot;
581 /* Removes temporary slot TEMP from LIST. */
583 static void
584 cut_slot_from_list (struct temp_slot *temp, struct temp_slot **list)
586 if (temp->next)
587 temp->next->prev = temp->prev;
588 if (temp->prev)
589 temp->prev->next = temp->next;
590 else
591 *list = temp->next;
593 temp->prev = temp->next = NULL;
596 /* Inserts temporary slot TEMP to LIST. */
598 static void
599 insert_slot_to_list (struct temp_slot *temp, struct temp_slot **list)
601 temp->next = *list;
602 if (*list)
603 (*list)->prev = temp;
604 temp->prev = NULL;
605 *list = temp;
608 /* Returns the list of used temp slots at LEVEL. */
610 static struct temp_slot **
611 temp_slots_at_level (int level)
613 if (level >= (int) VEC_length (temp_slot_p, used_temp_slots))
614 VEC_safe_grow_cleared (temp_slot_p, gc, used_temp_slots, level + 1);
616 return &(VEC_address (temp_slot_p, used_temp_slots)[level]);
619 /* Returns the maximal temporary slot level. */
621 static int
622 max_slot_level (void)
624 if (!used_temp_slots)
625 return -1;
627 return VEC_length (temp_slot_p, used_temp_slots) - 1;
630 /* Moves temporary slot TEMP to LEVEL. */
632 static void
633 move_slot_to_level (struct temp_slot *temp, int level)
635 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
636 insert_slot_to_list (temp, temp_slots_at_level (level));
637 temp->level = level;
640 /* Make temporary slot TEMP available. */
642 static void
643 make_slot_available (struct temp_slot *temp)
645 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
646 insert_slot_to_list (temp, &avail_temp_slots);
647 temp->in_use = 0;
648 temp->level = -1;
651 /* Compute the hash value for an address -> temp slot mapping.
652 The value is cached on the mapping entry. */
653 static hashval_t
654 temp_slot_address_compute_hash (struct temp_slot_address_entry *t)
656 int do_not_record = 0;
657 return hash_rtx (t->address, GET_MODE (t->address),
658 &do_not_record, NULL, false);
661 /* Return the hash value for an address -> temp slot mapping. */
662 static hashval_t
663 temp_slot_address_hash (const void *p)
665 const struct temp_slot_address_entry *t;
666 t = (const struct temp_slot_address_entry *) p;
667 return t->hash;
670 /* Compare two address -> temp slot mapping entries. */
671 static int
672 temp_slot_address_eq (const void *p1, const void *p2)
674 const struct temp_slot_address_entry *t1, *t2;
675 t1 = (const struct temp_slot_address_entry *) p1;
676 t2 = (const struct temp_slot_address_entry *) p2;
677 return exp_equiv_p (t1->address, t2->address, 0, true);
680 /* Add ADDRESS as an alias of TEMP_SLOT to the addess -> temp slot mapping. */
681 static void
682 insert_temp_slot_address (rtx address, struct temp_slot *temp_slot)
684 void **slot;
685 struct temp_slot_address_entry *t = ggc_alloc_temp_slot_address_entry ();
686 t->address = address;
687 t->temp_slot = temp_slot;
688 t->hash = temp_slot_address_compute_hash (t);
689 slot = htab_find_slot_with_hash (temp_slot_address_table, t, t->hash, INSERT);
690 *slot = t;
693 /* Remove an address -> temp slot mapping entry if the temp slot is
694 not in use anymore. Callback for remove_unused_temp_slot_addresses. */
695 static int
696 remove_unused_temp_slot_addresses_1 (void **slot, void *data ATTRIBUTE_UNUSED)
698 const struct temp_slot_address_entry *t;
699 t = (const struct temp_slot_address_entry *) *slot;
700 if (! t->temp_slot->in_use)
701 *slot = NULL;
702 return 1;
705 /* Remove all mappings of addresses to unused temp slots. */
706 static void
707 remove_unused_temp_slot_addresses (void)
709 htab_traverse (temp_slot_address_table,
710 remove_unused_temp_slot_addresses_1,
711 NULL);
714 /* Find the temp slot corresponding to the object at address X. */
716 static struct temp_slot *
717 find_temp_slot_from_address (rtx x)
719 struct temp_slot *p;
720 struct temp_slot_address_entry tmp, *t;
722 /* First try the easy way:
723 See if X exists in the address -> temp slot mapping. */
724 tmp.address = x;
725 tmp.temp_slot = NULL;
726 tmp.hash = temp_slot_address_compute_hash (&tmp);
727 t = (struct temp_slot_address_entry *)
728 htab_find_with_hash (temp_slot_address_table, &tmp, tmp.hash);
729 if (t)
730 return t->temp_slot;
732 /* If we have a sum involving a register, see if it points to a temp
733 slot. */
734 if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 0))
735 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
736 return p;
737 else if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 1))
738 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
739 return p;
741 /* Last resort: Address is a virtual stack var address. */
742 if (GET_CODE (x) == PLUS
743 && XEXP (x, 0) == virtual_stack_vars_rtx
744 && CONST_INT_P (XEXP (x, 1)))
746 int i;
747 for (i = max_slot_level (); i >= 0; i--)
748 for (p = *temp_slots_at_level (i); p; p = p->next)
750 if (INTVAL (XEXP (x, 1)) >= p->base_offset
751 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size)
752 return p;
756 return NULL;
759 /* Allocate a temporary stack slot and record it for possible later
760 reuse.
762 MODE is the machine mode to be given to the returned rtx.
764 SIZE is the size in units of the space required. We do no rounding here
765 since assign_stack_local will do any required rounding.
767 KEEP is 1 if this slot is to be retained after a call to
768 free_temp_slots. Automatic variables for a block are allocated
769 with this flag. KEEP values of 2 or 3 were needed respectively
770 for variables whose lifetime is controlled by CLEANUP_POINT_EXPRs
771 or for SAVE_EXPRs, but they are now unused.
773 TYPE is the type that will be used for the stack slot. */
776 assign_stack_temp_for_type (enum machine_mode mode, HOST_WIDE_INT size,
777 int keep, tree type)
779 unsigned int align;
780 struct temp_slot *p, *best_p = 0, *selected = NULL, **pp;
781 rtx slot;
783 /* If SIZE is -1 it means that somebody tried to allocate a temporary
784 of a variable size. */
785 gcc_assert (size != -1);
787 /* These are now unused. */
788 gcc_assert (keep <= 1);
790 align = get_stack_local_alignment (type, mode);
792 /* Try to find an available, already-allocated temporary of the proper
793 mode which meets the size and alignment requirements. Choose the
794 smallest one with the closest alignment.
796 If assign_stack_temp is called outside of the tree->rtl expansion,
797 we cannot reuse the stack slots (that may still refer to
798 VIRTUAL_STACK_VARS_REGNUM). */
799 if (!virtuals_instantiated)
801 for (p = avail_temp_slots; p; p = p->next)
803 if (p->align >= align && p->size >= size
804 && GET_MODE (p->slot) == mode
805 && objects_must_conflict_p (p->type, type)
806 && (best_p == 0 || best_p->size > p->size
807 || (best_p->size == p->size && best_p->align > p->align)))
809 if (p->align == align && p->size == size)
811 selected = p;
812 cut_slot_from_list (selected, &avail_temp_slots);
813 best_p = 0;
814 break;
816 best_p = p;
821 /* Make our best, if any, the one to use. */
822 if (best_p)
824 selected = best_p;
825 cut_slot_from_list (selected, &avail_temp_slots);
827 /* If there are enough aligned bytes left over, make them into a new
828 temp_slot so that the extra bytes don't get wasted. Do this only
829 for BLKmode slots, so that we can be sure of the alignment. */
830 if (GET_MODE (best_p->slot) == BLKmode)
832 int alignment = best_p->align / BITS_PER_UNIT;
833 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
835 if (best_p->size - rounded_size >= alignment)
837 p = ggc_alloc_temp_slot ();
838 p->in_use = p->addr_taken = 0;
839 p->size = best_p->size - rounded_size;
840 p->base_offset = best_p->base_offset + rounded_size;
841 p->full_size = best_p->full_size - rounded_size;
842 p->slot = adjust_address_nv (best_p->slot, BLKmode, rounded_size);
843 p->align = best_p->align;
844 p->type = best_p->type;
845 insert_slot_to_list (p, &avail_temp_slots);
847 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
848 stack_slot_list);
850 best_p->size = rounded_size;
851 best_p->full_size = rounded_size;
856 /* If we still didn't find one, make a new temporary. */
857 if (selected == 0)
859 HOST_WIDE_INT frame_offset_old = frame_offset;
861 p = ggc_alloc_temp_slot ();
863 /* We are passing an explicit alignment request to assign_stack_local.
864 One side effect of that is assign_stack_local will not round SIZE
865 to ensure the frame offset remains suitably aligned.
867 So for requests which depended on the rounding of SIZE, we go ahead
868 and round it now. We also make sure ALIGNMENT is at least
869 BIGGEST_ALIGNMENT. */
870 gcc_assert (mode != BLKmode || align == BIGGEST_ALIGNMENT);
871 p->slot = assign_stack_local (mode,
872 (mode == BLKmode
873 ? CEIL_ROUND (size, (int) align / BITS_PER_UNIT)
874 : size),
875 align);
877 p->align = align;
879 /* The following slot size computation is necessary because we don't
880 know the actual size of the temporary slot until assign_stack_local
881 has performed all the frame alignment and size rounding for the
882 requested temporary. Note that extra space added for alignment
883 can be either above or below this stack slot depending on which
884 way the frame grows. We include the extra space if and only if it
885 is above this slot. */
886 if (FRAME_GROWS_DOWNWARD)
887 p->size = frame_offset_old - frame_offset;
888 else
889 p->size = size;
891 /* Now define the fields used by combine_temp_slots. */
892 if (FRAME_GROWS_DOWNWARD)
894 p->base_offset = frame_offset;
895 p->full_size = frame_offset_old - frame_offset;
897 else
899 p->base_offset = frame_offset_old;
900 p->full_size = frame_offset - frame_offset_old;
903 selected = p;
906 p = selected;
907 p->in_use = 1;
908 p->addr_taken = 0;
909 p->type = type;
910 p->level = temp_slot_level;
911 p->keep = keep;
913 pp = temp_slots_at_level (p->level);
914 insert_slot_to_list (p, pp);
915 insert_temp_slot_address (XEXP (p->slot, 0), p);
917 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
918 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
919 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list);
921 /* If we know the alias set for the memory that will be used, use
922 it. If there's no TYPE, then we don't know anything about the
923 alias set for the memory. */
924 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
925 set_mem_align (slot, align);
927 /* If a type is specified, set the relevant flags. */
928 if (type != 0)
930 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
931 MEM_SET_IN_STRUCT_P (slot, (AGGREGATE_TYPE_P (type)
932 || TREE_CODE (type) == COMPLEX_TYPE));
934 MEM_NOTRAP_P (slot) = 1;
936 return slot;
939 /* Allocate a temporary stack slot and record it for possible later
940 reuse. First three arguments are same as in preceding function. */
943 assign_stack_temp (enum machine_mode mode, HOST_WIDE_INT size, int keep)
945 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
948 /* Assign a temporary.
949 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
950 and so that should be used in error messages. In either case, we
951 allocate of the given type.
952 KEEP is as for assign_stack_temp.
953 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
954 it is 0 if a register is OK.
955 DONT_PROMOTE is 1 if we should not promote values in register
956 to wider modes. */
959 assign_temp (tree type_or_decl, int keep, int memory_required,
960 int dont_promote ATTRIBUTE_UNUSED)
962 tree type, decl;
963 enum machine_mode mode;
964 #ifdef PROMOTE_MODE
965 int unsignedp;
966 #endif
968 if (DECL_P (type_or_decl))
969 decl = type_or_decl, type = TREE_TYPE (decl);
970 else
971 decl = NULL, type = type_or_decl;
973 mode = TYPE_MODE (type);
974 #ifdef PROMOTE_MODE
975 unsignedp = TYPE_UNSIGNED (type);
976 #endif
978 if (mode == BLKmode || memory_required)
980 HOST_WIDE_INT size = int_size_in_bytes (type);
981 rtx tmp;
983 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
984 problems with allocating the stack space. */
985 if (size == 0)
986 size = 1;
988 /* Unfortunately, we don't yet know how to allocate variable-sized
989 temporaries. However, sometimes we can find a fixed upper limit on
990 the size, so try that instead. */
991 else if (size == -1)
992 size = max_int_size_in_bytes (type);
994 /* The size of the temporary may be too large to fit into an integer. */
995 /* ??? Not sure this should happen except for user silliness, so limit
996 this to things that aren't compiler-generated temporaries. The
997 rest of the time we'll die in assign_stack_temp_for_type. */
998 if (decl && size == -1
999 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
1001 error ("size of variable %q+D is too large", decl);
1002 size = 1;
1005 tmp = assign_stack_temp_for_type (mode, size, keep, type);
1006 return tmp;
1009 #ifdef PROMOTE_MODE
1010 if (! dont_promote)
1011 mode = promote_mode (type, mode, &unsignedp);
1012 #endif
1014 return gen_reg_rtx (mode);
1017 /* Combine temporary stack slots which are adjacent on the stack.
1019 This allows for better use of already allocated stack space. This is only
1020 done for BLKmode slots because we can be sure that we won't have alignment
1021 problems in this case. */
1023 static void
1024 combine_temp_slots (void)
1026 struct temp_slot *p, *q, *next, *next_q;
1027 int num_slots;
1029 /* We can't combine slots, because the information about which slot
1030 is in which alias set will be lost. */
1031 if (flag_strict_aliasing)
1032 return;
1034 /* If there are a lot of temp slots, don't do anything unless
1035 high levels of optimization. */
1036 if (! flag_expensive_optimizations)
1037 for (p = avail_temp_slots, num_slots = 0; p; p = p->next, num_slots++)
1038 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
1039 return;
1041 for (p = avail_temp_slots; p; p = next)
1043 int delete_p = 0;
1045 next = p->next;
1047 if (GET_MODE (p->slot) != BLKmode)
1048 continue;
1050 for (q = p->next; q; q = next_q)
1052 int delete_q = 0;
1054 next_q = q->next;
1056 if (GET_MODE (q->slot) != BLKmode)
1057 continue;
1059 if (p->base_offset + p->full_size == q->base_offset)
1061 /* Q comes after P; combine Q into P. */
1062 p->size += q->size;
1063 p->full_size += q->full_size;
1064 delete_q = 1;
1066 else if (q->base_offset + q->full_size == p->base_offset)
1068 /* P comes after Q; combine P into Q. */
1069 q->size += p->size;
1070 q->full_size += p->full_size;
1071 delete_p = 1;
1072 break;
1074 if (delete_q)
1075 cut_slot_from_list (q, &avail_temp_slots);
1078 /* Either delete P or advance past it. */
1079 if (delete_p)
1080 cut_slot_from_list (p, &avail_temp_slots);
1084 /* Indicate that NEW_RTX is an alternate way of referring to the temp
1085 slot that previously was known by OLD_RTX. */
1087 void
1088 update_temp_slot_address (rtx old_rtx, rtx new_rtx)
1090 struct temp_slot *p;
1092 if (rtx_equal_p (old_rtx, new_rtx))
1093 return;
1095 p = find_temp_slot_from_address (old_rtx);
1097 /* If we didn't find one, see if both OLD_RTX is a PLUS. If so, and
1098 NEW_RTX is a register, see if one operand of the PLUS is a
1099 temporary location. If so, NEW_RTX points into it. Otherwise,
1100 if both OLD_RTX and NEW_RTX are a PLUS and if there is a register
1101 in common between them. If so, try a recursive call on those
1102 values. */
1103 if (p == 0)
1105 if (GET_CODE (old_rtx) != PLUS)
1106 return;
1108 if (REG_P (new_rtx))
1110 update_temp_slot_address (XEXP (old_rtx, 0), new_rtx);
1111 update_temp_slot_address (XEXP (old_rtx, 1), new_rtx);
1112 return;
1114 else if (GET_CODE (new_rtx) != PLUS)
1115 return;
1117 if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 0)))
1118 update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 1));
1119 else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 0)))
1120 update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 1));
1121 else if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 1)))
1122 update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 0));
1123 else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 1)))
1124 update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 0));
1126 return;
1129 /* Otherwise add an alias for the temp's address. */
1130 insert_temp_slot_address (new_rtx, p);
1133 /* If X could be a reference to a temporary slot, mark the fact that its
1134 address was taken. */
1136 void
1137 mark_temp_addr_taken (rtx x)
1139 struct temp_slot *p;
1141 if (x == 0)
1142 return;
1144 /* If X is not in memory or is at a constant address, it cannot be in
1145 a temporary slot. */
1146 if (!MEM_P (x) || CONSTANT_P (XEXP (x, 0)))
1147 return;
1149 p = find_temp_slot_from_address (XEXP (x, 0));
1150 if (p != 0)
1151 p->addr_taken = 1;
1154 /* If X could be a reference to a temporary slot, mark that slot as
1155 belonging to the to one level higher than the current level. If X
1156 matched one of our slots, just mark that one. Otherwise, we can't
1157 easily predict which it is, so upgrade all of them. Kept slots
1158 need not be touched.
1160 This is called when an ({...}) construct occurs and a statement
1161 returns a value in memory. */
1163 void
1164 preserve_temp_slots (rtx x)
1166 struct temp_slot *p = 0, *next;
1168 /* If there is no result, we still might have some objects whose address
1169 were taken, so we need to make sure they stay around. */
1170 if (x == 0)
1172 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1174 next = p->next;
1176 if (p->addr_taken)
1177 move_slot_to_level (p, temp_slot_level - 1);
1180 return;
1183 /* If X is a register that is being used as a pointer, see if we have
1184 a temporary slot we know it points to. To be consistent with
1185 the code below, we really should preserve all non-kept slots
1186 if we can't find a match, but that seems to be much too costly. */
1187 if (REG_P (x) && REG_POINTER (x))
1188 p = find_temp_slot_from_address (x);
1190 /* If X is not in memory or is at a constant address, it cannot be in
1191 a temporary slot, but it can contain something whose address was
1192 taken. */
1193 if (p == 0 && (!MEM_P (x) || CONSTANT_P (XEXP (x, 0))))
1195 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1197 next = p->next;
1199 if (p->addr_taken)
1200 move_slot_to_level (p, temp_slot_level - 1);
1203 return;
1206 /* First see if we can find a match. */
1207 if (p == 0)
1208 p = find_temp_slot_from_address (XEXP (x, 0));
1210 if (p != 0)
1212 /* Move everything at our level whose address was taken to our new
1213 level in case we used its address. */
1214 struct temp_slot *q;
1216 if (p->level == temp_slot_level)
1218 for (q = *temp_slots_at_level (temp_slot_level); q; q = next)
1220 next = q->next;
1222 if (p != q && q->addr_taken)
1223 move_slot_to_level (q, temp_slot_level - 1);
1226 move_slot_to_level (p, temp_slot_level - 1);
1227 p->addr_taken = 0;
1229 return;
1232 /* Otherwise, preserve all non-kept slots at this level. */
1233 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1235 next = p->next;
1237 if (!p->keep)
1238 move_slot_to_level (p, temp_slot_level - 1);
1242 /* Free all temporaries used so far. This is normally called at the
1243 end of generating code for a statement. */
1245 void
1246 free_temp_slots (void)
1248 struct temp_slot *p, *next;
1249 bool some_available = false;
1251 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1253 next = p->next;
1255 if (!p->keep)
1257 make_slot_available (p);
1258 some_available = true;
1262 if (some_available)
1264 remove_unused_temp_slot_addresses ();
1265 combine_temp_slots ();
1269 /* Push deeper into the nesting level for stack temporaries. */
1271 void
1272 push_temp_slots (void)
1274 temp_slot_level++;
1277 /* Pop a temporary nesting level. All slots in use in the current level
1278 are freed. */
1280 void
1281 pop_temp_slots (void)
1283 struct temp_slot *p, *next;
1284 bool some_available = false;
1286 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1288 next = p->next;
1289 make_slot_available (p);
1290 some_available = true;
1293 if (some_available)
1295 remove_unused_temp_slot_addresses ();
1296 combine_temp_slots ();
1299 temp_slot_level--;
1302 /* Initialize temporary slots. */
1304 void
1305 init_temp_slots (void)
1307 /* We have not allocated any temporaries yet. */
1308 avail_temp_slots = 0;
1309 used_temp_slots = 0;
1310 temp_slot_level = 0;
1312 /* Set up the table to map addresses to temp slots. */
1313 if (! temp_slot_address_table)
1314 temp_slot_address_table = htab_create_ggc (32,
1315 temp_slot_address_hash,
1316 temp_slot_address_eq,
1317 NULL);
1318 else
1319 htab_empty (temp_slot_address_table);
1322 /* These routines are responsible for converting virtual register references
1323 to the actual hard register references once RTL generation is complete.
1325 The following four variables are used for communication between the
1326 routines. They contain the offsets of the virtual registers from their
1327 respective hard registers. */
1329 static int in_arg_offset;
1330 static int var_offset;
1331 static int dynamic_offset;
1332 static int out_arg_offset;
1333 static int cfa_offset;
1335 /* In most machines, the stack pointer register is equivalent to the bottom
1336 of the stack. */
1338 #ifndef STACK_POINTER_OFFSET
1339 #define STACK_POINTER_OFFSET 0
1340 #endif
1342 /* If not defined, pick an appropriate default for the offset of dynamically
1343 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1344 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1346 #ifndef STACK_DYNAMIC_OFFSET
1348 /* The bottom of the stack points to the actual arguments. If
1349 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1350 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1351 stack space for register parameters is not pushed by the caller, but
1352 rather part of the fixed stack areas and hence not included in
1353 `crtl->outgoing_args_size'. Nevertheless, we must allow
1354 for it when allocating stack dynamic objects. */
1356 #if defined(REG_PARM_STACK_SPACE)
1357 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1358 ((ACCUMULATE_OUTGOING_ARGS \
1359 ? (crtl->outgoing_args_size \
1360 + (OUTGOING_REG_PARM_STACK_SPACE ((!(FNDECL) ? NULL_TREE : TREE_TYPE (FNDECL))) ? 0 \
1361 : REG_PARM_STACK_SPACE (FNDECL))) \
1362 : 0) + (STACK_POINTER_OFFSET))
1363 #else
1364 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1365 ((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : 0) \
1366 + (STACK_POINTER_OFFSET))
1367 #endif
1368 #endif
1371 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1372 is a virtual register, return the equivalent hard register and set the
1373 offset indirectly through the pointer. Otherwise, return 0. */
1375 static rtx
1376 instantiate_new_reg (rtx x, HOST_WIDE_INT *poffset)
1378 rtx new_rtx;
1379 HOST_WIDE_INT offset;
1381 if (x == virtual_incoming_args_rtx)
1383 if (stack_realign_drap)
1385 /* Replace virtual_incoming_args_rtx with internal arg
1386 pointer if DRAP is used to realign stack. */
1387 new_rtx = crtl->args.internal_arg_pointer;
1388 offset = 0;
1390 else
1391 new_rtx = arg_pointer_rtx, offset = in_arg_offset;
1393 else if (x == virtual_stack_vars_rtx)
1394 new_rtx = frame_pointer_rtx, offset = var_offset;
1395 else if (x == virtual_stack_dynamic_rtx)
1396 new_rtx = stack_pointer_rtx, offset = dynamic_offset;
1397 else if (x == virtual_outgoing_args_rtx)
1398 new_rtx = stack_pointer_rtx, offset = out_arg_offset;
1399 else if (x == virtual_cfa_rtx)
1401 #ifdef FRAME_POINTER_CFA_OFFSET
1402 new_rtx = frame_pointer_rtx;
1403 #else
1404 new_rtx = arg_pointer_rtx;
1405 #endif
1406 offset = cfa_offset;
1408 else
1409 return NULL_RTX;
1411 *poffset = offset;
1412 return new_rtx;
1415 /* A subroutine of instantiate_virtual_regs, called via for_each_rtx.
1416 Instantiate any virtual registers present inside of *LOC. The expression
1417 is simplified, as much as possible, but is not to be considered "valid"
1418 in any sense implied by the target. If any change is made, set CHANGED
1419 to true. */
1421 static int
1422 instantiate_virtual_regs_in_rtx (rtx *loc, void *data)
1424 HOST_WIDE_INT offset;
1425 bool *changed = (bool *) data;
1426 rtx x, new_rtx;
1428 x = *loc;
1429 if (x == 0)
1430 return 0;
1432 switch (GET_CODE (x))
1434 case REG:
1435 new_rtx = instantiate_new_reg (x, &offset);
1436 if (new_rtx)
1438 *loc = plus_constant (new_rtx, offset);
1439 if (changed)
1440 *changed = true;
1442 return -1;
1444 case PLUS:
1445 new_rtx = instantiate_new_reg (XEXP (x, 0), &offset);
1446 if (new_rtx)
1448 new_rtx = plus_constant (new_rtx, offset);
1449 *loc = simplify_gen_binary (PLUS, GET_MODE (x), new_rtx, XEXP (x, 1));
1450 if (changed)
1451 *changed = true;
1452 return -1;
1455 /* FIXME -- from old code */
1456 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1457 we can commute the PLUS and SUBREG because pointers into the
1458 frame are well-behaved. */
1459 break;
1461 default:
1462 break;
1465 return 0;
1468 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1469 matches the predicate for insn CODE operand OPERAND. */
1471 static int
1472 safe_insn_predicate (int code, int operand, rtx x)
1474 const struct insn_operand_data *op_data;
1476 if (code < 0)
1477 return true;
1479 op_data = &insn_data[code].operand[operand];
1480 if (op_data->predicate == NULL)
1481 return true;
1483 return op_data->predicate (x, op_data->mode);
1486 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1487 registers present inside of insn. The result will be a valid insn. */
1489 static void
1490 instantiate_virtual_regs_in_insn (rtx insn)
1492 HOST_WIDE_INT offset;
1493 int insn_code, i;
1494 bool any_change = false;
1495 rtx set, new_rtx, x, seq;
1497 /* There are some special cases to be handled first. */
1498 set = single_set (insn);
1499 if (set)
1501 /* We're allowed to assign to a virtual register. This is interpreted
1502 to mean that the underlying register gets assigned the inverse
1503 transformation. This is used, for example, in the handling of
1504 non-local gotos. */
1505 new_rtx = instantiate_new_reg (SET_DEST (set), &offset);
1506 if (new_rtx)
1508 start_sequence ();
1510 for_each_rtx (&SET_SRC (set), instantiate_virtual_regs_in_rtx, NULL);
1511 x = simplify_gen_binary (PLUS, GET_MODE (new_rtx), SET_SRC (set),
1512 GEN_INT (-offset));
1513 x = force_operand (x, new_rtx);
1514 if (x != new_rtx)
1515 emit_move_insn (new_rtx, x);
1517 seq = get_insns ();
1518 end_sequence ();
1520 emit_insn_before (seq, insn);
1521 delete_insn (insn);
1522 return;
1525 /* Handle a straight copy from a virtual register by generating a
1526 new add insn. The difference between this and falling through
1527 to the generic case is avoiding a new pseudo and eliminating a
1528 move insn in the initial rtl stream. */
1529 new_rtx = instantiate_new_reg (SET_SRC (set), &offset);
1530 if (new_rtx && offset != 0
1531 && REG_P (SET_DEST (set))
1532 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1534 start_sequence ();
1536 x = expand_simple_binop (GET_MODE (SET_DEST (set)), PLUS,
1537 new_rtx, GEN_INT (offset), SET_DEST (set),
1538 1, OPTAB_LIB_WIDEN);
1539 if (x != SET_DEST (set))
1540 emit_move_insn (SET_DEST (set), x);
1542 seq = get_insns ();
1543 end_sequence ();
1545 emit_insn_before (seq, insn);
1546 delete_insn (insn);
1547 return;
1550 extract_insn (insn);
1551 insn_code = INSN_CODE (insn);
1553 /* Handle a plus involving a virtual register by determining if the
1554 operands remain valid if they're modified in place. */
1555 if (GET_CODE (SET_SRC (set)) == PLUS
1556 && recog_data.n_operands >= 3
1557 && recog_data.operand_loc[1] == &XEXP (SET_SRC (set), 0)
1558 && recog_data.operand_loc[2] == &XEXP (SET_SRC (set), 1)
1559 && CONST_INT_P (recog_data.operand[2])
1560 && (new_rtx = instantiate_new_reg (recog_data.operand[1], &offset)))
1562 offset += INTVAL (recog_data.operand[2]);
1564 /* If the sum is zero, then replace with a plain move. */
1565 if (offset == 0
1566 && REG_P (SET_DEST (set))
1567 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1569 start_sequence ();
1570 emit_move_insn (SET_DEST (set), new_rtx);
1571 seq = get_insns ();
1572 end_sequence ();
1574 emit_insn_before (seq, insn);
1575 delete_insn (insn);
1576 return;
1579 x = gen_int_mode (offset, recog_data.operand_mode[2]);
1581 /* Using validate_change and apply_change_group here leaves
1582 recog_data in an invalid state. Since we know exactly what
1583 we want to check, do those two by hand. */
1584 if (safe_insn_predicate (insn_code, 1, new_rtx)
1585 && safe_insn_predicate (insn_code, 2, x))
1587 *recog_data.operand_loc[1] = recog_data.operand[1] = new_rtx;
1588 *recog_data.operand_loc[2] = recog_data.operand[2] = x;
1589 any_change = true;
1591 /* Fall through into the regular operand fixup loop in
1592 order to take care of operands other than 1 and 2. */
1596 else
1598 extract_insn (insn);
1599 insn_code = INSN_CODE (insn);
1602 /* In the general case, we expect virtual registers to appear only in
1603 operands, and then only as either bare registers or inside memories. */
1604 for (i = 0; i < recog_data.n_operands; ++i)
1606 x = recog_data.operand[i];
1607 switch (GET_CODE (x))
1609 case MEM:
1611 rtx addr = XEXP (x, 0);
1612 bool changed = false;
1614 for_each_rtx (&addr, instantiate_virtual_regs_in_rtx, &changed);
1615 if (!changed)
1616 continue;
1618 start_sequence ();
1619 x = replace_equiv_address (x, addr);
1620 /* It may happen that the address with the virtual reg
1621 was valid (e.g. based on the virtual stack reg, which might
1622 be acceptable to the predicates with all offsets), whereas
1623 the address now isn't anymore, for instance when the address
1624 is still offsetted, but the base reg isn't virtual-stack-reg
1625 anymore. Below we would do a force_reg on the whole operand,
1626 but this insn might actually only accept memory. Hence,
1627 before doing that last resort, try to reload the address into
1628 a register, so this operand stays a MEM. */
1629 if (!safe_insn_predicate (insn_code, i, x))
1631 addr = force_reg (GET_MODE (addr), addr);
1632 x = replace_equiv_address (x, addr);
1634 seq = get_insns ();
1635 end_sequence ();
1636 if (seq)
1637 emit_insn_before (seq, insn);
1639 break;
1641 case REG:
1642 new_rtx = instantiate_new_reg (x, &offset);
1643 if (new_rtx == NULL)
1644 continue;
1645 if (offset == 0)
1646 x = new_rtx;
1647 else
1649 start_sequence ();
1651 /* Careful, special mode predicates may have stuff in
1652 insn_data[insn_code].operand[i].mode that isn't useful
1653 to us for computing a new value. */
1654 /* ??? Recognize address_operand and/or "p" constraints
1655 to see if (plus new offset) is a valid before we put
1656 this through expand_simple_binop. */
1657 x = expand_simple_binop (GET_MODE (x), PLUS, new_rtx,
1658 GEN_INT (offset), NULL_RTX,
1659 1, OPTAB_LIB_WIDEN);
1660 seq = get_insns ();
1661 end_sequence ();
1662 emit_insn_before (seq, insn);
1664 break;
1666 case SUBREG:
1667 new_rtx = instantiate_new_reg (SUBREG_REG (x), &offset);
1668 if (new_rtx == NULL)
1669 continue;
1670 if (offset != 0)
1672 start_sequence ();
1673 new_rtx = expand_simple_binop (GET_MODE (new_rtx), PLUS, new_rtx,
1674 GEN_INT (offset), NULL_RTX,
1675 1, OPTAB_LIB_WIDEN);
1676 seq = get_insns ();
1677 end_sequence ();
1678 emit_insn_before (seq, insn);
1680 x = simplify_gen_subreg (recog_data.operand_mode[i], new_rtx,
1681 GET_MODE (new_rtx), SUBREG_BYTE (x));
1682 gcc_assert (x);
1683 break;
1685 default:
1686 continue;
1689 /* At this point, X contains the new value for the operand.
1690 Validate the new value vs the insn predicate. Note that
1691 asm insns will have insn_code -1 here. */
1692 if (!safe_insn_predicate (insn_code, i, x))
1694 start_sequence ();
1695 if (REG_P (x))
1697 gcc_assert (REGNO (x) <= LAST_VIRTUAL_REGISTER);
1698 x = copy_to_reg (x);
1700 else
1701 x = force_reg (insn_data[insn_code].operand[i].mode, x);
1702 seq = get_insns ();
1703 end_sequence ();
1704 if (seq)
1705 emit_insn_before (seq, insn);
1708 *recog_data.operand_loc[i] = recog_data.operand[i] = x;
1709 any_change = true;
1712 if (any_change)
1714 /* Propagate operand changes into the duplicates. */
1715 for (i = 0; i < recog_data.n_dups; ++i)
1716 *recog_data.dup_loc[i]
1717 = copy_rtx (recog_data.operand[(unsigned)recog_data.dup_num[i]]);
1719 /* Force re-recognition of the instruction for validation. */
1720 INSN_CODE (insn) = -1;
1723 if (asm_noperands (PATTERN (insn)) >= 0)
1725 if (!check_asm_operands (PATTERN (insn)))
1727 error_for_asm (insn, "impossible constraint in %<asm%>");
1728 delete_insn (insn);
1731 else
1733 if (recog_memoized (insn) < 0)
1734 fatal_insn_not_found (insn);
1738 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1739 do any instantiation required. */
1741 void
1742 instantiate_decl_rtl (rtx x)
1744 rtx addr;
1746 if (x == 0)
1747 return;
1749 /* If this is a CONCAT, recurse for the pieces. */
1750 if (GET_CODE (x) == CONCAT)
1752 instantiate_decl_rtl (XEXP (x, 0));
1753 instantiate_decl_rtl (XEXP (x, 1));
1754 return;
1757 /* If this is not a MEM, no need to do anything. Similarly if the
1758 address is a constant or a register that is not a virtual register. */
1759 if (!MEM_P (x))
1760 return;
1762 addr = XEXP (x, 0);
1763 if (CONSTANT_P (addr)
1764 || (REG_P (addr)
1765 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
1766 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
1767 return;
1769 for_each_rtx (&XEXP (x, 0), instantiate_virtual_regs_in_rtx, NULL);
1772 /* Helper for instantiate_decls called via walk_tree: Process all decls
1773 in the given DECL_VALUE_EXPR. */
1775 static tree
1776 instantiate_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
1778 tree t = *tp;
1779 if (! EXPR_P (t))
1781 *walk_subtrees = 0;
1782 if (DECL_P (t) && DECL_RTL_SET_P (t))
1783 instantiate_decl_rtl (DECL_RTL (t));
1785 return NULL;
1788 /* Subroutine of instantiate_decls: Process all decls in the given
1789 BLOCK node and all its subblocks. */
1791 static void
1792 instantiate_decls_1 (tree let)
1794 tree t;
1796 for (t = BLOCK_VARS (let); t; t = DECL_CHAIN (t))
1798 if (DECL_RTL_SET_P (t))
1799 instantiate_decl_rtl (DECL_RTL (t));
1800 if (TREE_CODE (t) == VAR_DECL && DECL_HAS_VALUE_EXPR_P (t))
1802 tree v = DECL_VALUE_EXPR (t);
1803 walk_tree (&v, instantiate_expr, NULL, NULL);
1807 /* Process all subblocks. */
1808 for (t = BLOCK_SUBBLOCKS (let); t; t = BLOCK_CHAIN (t))
1809 instantiate_decls_1 (t);
1812 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1813 all virtual registers in their DECL_RTL's. */
1815 static void
1816 instantiate_decls (tree fndecl)
1818 tree decl;
1819 unsigned ix;
1821 /* Process all parameters of the function. */
1822 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = DECL_CHAIN (decl))
1824 instantiate_decl_rtl (DECL_RTL (decl));
1825 instantiate_decl_rtl (DECL_INCOMING_RTL (decl));
1826 if (DECL_HAS_VALUE_EXPR_P (decl))
1828 tree v = DECL_VALUE_EXPR (decl);
1829 walk_tree (&v, instantiate_expr, NULL, NULL);
1833 /* Now process all variables defined in the function or its subblocks. */
1834 instantiate_decls_1 (DECL_INITIAL (fndecl));
1836 FOR_EACH_LOCAL_DECL (cfun, ix, decl)
1837 if (DECL_RTL_SET_P (decl))
1838 instantiate_decl_rtl (DECL_RTL (decl));
1839 VEC_free (tree, gc, cfun->local_decls);
1842 /* Pass through the INSNS of function FNDECL and convert virtual register
1843 references to hard register references. */
1845 static unsigned int
1846 instantiate_virtual_regs (void)
1848 rtx insn;
1850 /* Compute the offsets to use for this function. */
1851 in_arg_offset = FIRST_PARM_OFFSET (current_function_decl);
1852 var_offset = STARTING_FRAME_OFFSET;
1853 dynamic_offset = STACK_DYNAMIC_OFFSET (current_function_decl);
1854 out_arg_offset = STACK_POINTER_OFFSET;
1855 #ifdef FRAME_POINTER_CFA_OFFSET
1856 cfa_offset = FRAME_POINTER_CFA_OFFSET (current_function_decl);
1857 #else
1858 cfa_offset = ARG_POINTER_CFA_OFFSET (current_function_decl);
1859 #endif
1861 /* Initialize recognition, indicating that volatile is OK. */
1862 init_recog ();
1864 /* Scan through all the insns, instantiating every virtual register still
1865 present. */
1866 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
1867 if (INSN_P (insn))
1869 /* These patterns in the instruction stream can never be recognized.
1870 Fortunately, they shouldn't contain virtual registers either. */
1871 if (GET_CODE (PATTERN (insn)) == USE
1872 || GET_CODE (PATTERN (insn)) == CLOBBER
1873 || GET_CODE (PATTERN (insn)) == ADDR_VEC
1874 || GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC
1875 || GET_CODE (PATTERN (insn)) == ASM_INPUT)
1876 continue;
1877 else if (DEBUG_INSN_P (insn))
1878 for_each_rtx (&INSN_VAR_LOCATION (insn),
1879 instantiate_virtual_regs_in_rtx, NULL);
1880 else
1881 instantiate_virtual_regs_in_insn (insn);
1883 if (INSN_DELETED_P (insn))
1884 continue;
1886 for_each_rtx (&REG_NOTES (insn), instantiate_virtual_regs_in_rtx, NULL);
1888 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1889 if (CALL_P (insn))
1890 for_each_rtx (&CALL_INSN_FUNCTION_USAGE (insn),
1891 instantiate_virtual_regs_in_rtx, NULL);
1894 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1895 instantiate_decls (current_function_decl);
1897 targetm.instantiate_decls ();
1899 /* Indicate that, from now on, assign_stack_local should use
1900 frame_pointer_rtx. */
1901 virtuals_instantiated = 1;
1902 return 0;
1905 struct rtl_opt_pass pass_instantiate_virtual_regs =
1908 RTL_PASS,
1909 "vregs", /* name */
1910 NULL, /* gate */
1911 instantiate_virtual_regs, /* execute */
1912 NULL, /* sub */
1913 NULL, /* next */
1914 0, /* static_pass_number */
1915 TV_NONE, /* tv_id */
1916 0, /* properties_required */
1917 0, /* properties_provided */
1918 0, /* properties_destroyed */
1919 0, /* todo_flags_start */
1920 TODO_dump_func /* todo_flags_finish */
1925 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
1926 This means a type for which function calls must pass an address to the
1927 function or get an address back from the function.
1928 EXP may be a type node or an expression (whose type is tested). */
1931 aggregate_value_p (const_tree exp, const_tree fntype)
1933 const_tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
1934 int i, regno, nregs;
1935 rtx reg;
1937 if (fntype)
1938 switch (TREE_CODE (fntype))
1940 case CALL_EXPR:
1942 tree fndecl = get_callee_fndecl (fntype);
1943 fntype = (fndecl
1944 ? TREE_TYPE (fndecl)
1945 : TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (fntype))));
1947 break;
1948 case FUNCTION_DECL:
1949 fntype = TREE_TYPE (fntype);
1950 break;
1951 case FUNCTION_TYPE:
1952 case METHOD_TYPE:
1953 break;
1954 case IDENTIFIER_NODE:
1955 fntype = NULL_TREE;
1956 break;
1957 default:
1958 /* We don't expect other tree types here. */
1959 gcc_unreachable ();
1962 if (VOID_TYPE_P (type))
1963 return 0;
1965 /* If a record should be passed the same as its first (and only) member
1966 don't pass it as an aggregate. */
1967 if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
1968 return aggregate_value_p (first_field (type), fntype);
1970 /* If the front end has decided that this needs to be passed by
1971 reference, do so. */
1972 if ((TREE_CODE (exp) == PARM_DECL || TREE_CODE (exp) == RESULT_DECL)
1973 && DECL_BY_REFERENCE (exp))
1974 return 1;
1976 /* Function types that are TREE_ADDRESSABLE force return in memory. */
1977 if (fntype && TREE_ADDRESSABLE (fntype))
1978 return 1;
1980 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
1981 and thus can't be returned in registers. */
1982 if (TREE_ADDRESSABLE (type))
1983 return 1;
1985 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
1986 return 1;
1988 if (targetm.calls.return_in_memory (type, fntype))
1989 return 1;
1991 /* Make sure we have suitable call-clobbered regs to return
1992 the value in; if not, we must return it in memory. */
1993 reg = hard_function_value (type, 0, fntype, 0);
1995 /* If we have something other than a REG (e.g. a PARALLEL), then assume
1996 it is OK. */
1997 if (!REG_P (reg))
1998 return 0;
2000 regno = REGNO (reg);
2001 nregs = hard_regno_nregs[regno][TYPE_MODE (type)];
2002 for (i = 0; i < nregs; i++)
2003 if (! call_used_regs[regno + i])
2004 return 1;
2006 return 0;
2009 /* Return true if we should assign DECL a pseudo register; false if it
2010 should live on the local stack. */
2012 bool
2013 use_register_for_decl (const_tree decl)
2015 if (!targetm.calls.allocate_stack_slots_for_args())
2016 return true;
2018 /* Honor volatile. */
2019 if (TREE_SIDE_EFFECTS (decl))
2020 return false;
2022 /* Honor addressability. */
2023 if (TREE_ADDRESSABLE (decl))
2024 return false;
2026 /* Only register-like things go in registers. */
2027 if (DECL_MODE (decl) == BLKmode)
2028 return false;
2030 /* If -ffloat-store specified, don't put explicit float variables
2031 into registers. */
2032 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
2033 propagates values across these stores, and it probably shouldn't. */
2034 if (flag_float_store && FLOAT_TYPE_P (TREE_TYPE (decl)))
2035 return false;
2037 /* If we're not interested in tracking debugging information for
2038 this decl, then we can certainly put it in a register. */
2039 if (DECL_IGNORED_P (decl))
2040 return true;
2042 if (optimize)
2043 return true;
2045 if (!DECL_REGISTER (decl))
2046 return false;
2048 switch (TREE_CODE (TREE_TYPE (decl)))
2050 case RECORD_TYPE:
2051 case UNION_TYPE:
2052 case QUAL_UNION_TYPE:
2053 /* When not optimizing, disregard register keyword for variables with
2054 types containing methods, otherwise the methods won't be callable
2055 from the debugger. */
2056 if (TYPE_METHODS (TREE_TYPE (decl)))
2057 return false;
2058 break;
2059 default:
2060 break;
2063 return true;
2066 /* Return true if TYPE should be passed by invisible reference. */
2068 bool
2069 pass_by_reference (CUMULATIVE_ARGS *ca, enum machine_mode mode,
2070 tree type, bool named_arg)
2072 if (type)
2074 /* If this type contains non-trivial constructors, then it is
2075 forbidden for the middle-end to create any new copies. */
2076 if (TREE_ADDRESSABLE (type))
2077 return true;
2079 /* GCC post 3.4 passes *all* variable sized types by reference. */
2080 if (!TYPE_SIZE (type) || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
2081 return true;
2083 /* If a record type should be passed the same as its first (and only)
2084 member, use the type and mode of that member. */
2085 if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
2087 type = TREE_TYPE (first_field (type));
2088 mode = TYPE_MODE (type);
2092 return targetm.calls.pass_by_reference (ca, mode, type, named_arg);
2095 /* Return true if TYPE, which is passed by reference, should be callee
2096 copied instead of caller copied. */
2098 bool
2099 reference_callee_copied (CUMULATIVE_ARGS *ca, enum machine_mode mode,
2100 tree type, bool named_arg)
2102 if (type && TREE_ADDRESSABLE (type))
2103 return false;
2104 return targetm.calls.callee_copies (ca, mode, type, named_arg);
2107 /* Structures to communicate between the subroutines of assign_parms.
2108 The first holds data persistent across all parameters, the second
2109 is cleared out for each parameter. */
2111 struct assign_parm_data_all
2113 CUMULATIVE_ARGS args_so_far;
2114 struct args_size stack_args_size;
2115 tree function_result_decl;
2116 tree orig_fnargs;
2117 rtx first_conversion_insn;
2118 rtx last_conversion_insn;
2119 HOST_WIDE_INT pretend_args_size;
2120 HOST_WIDE_INT extra_pretend_bytes;
2121 int reg_parm_stack_space;
2124 struct assign_parm_data_one
2126 tree nominal_type;
2127 tree passed_type;
2128 rtx entry_parm;
2129 rtx stack_parm;
2130 enum machine_mode nominal_mode;
2131 enum machine_mode passed_mode;
2132 enum machine_mode promoted_mode;
2133 struct locate_and_pad_arg_data locate;
2134 int partial;
2135 BOOL_BITFIELD named_arg : 1;
2136 BOOL_BITFIELD passed_pointer : 1;
2137 BOOL_BITFIELD on_stack : 1;
2138 BOOL_BITFIELD loaded_in_reg : 1;
2141 /* A subroutine of assign_parms. Initialize ALL. */
2143 static void
2144 assign_parms_initialize_all (struct assign_parm_data_all *all)
2146 tree fntype ATTRIBUTE_UNUSED;
2148 memset (all, 0, sizeof (*all));
2150 fntype = TREE_TYPE (current_function_decl);
2152 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
2153 INIT_CUMULATIVE_INCOMING_ARGS (all->args_so_far, fntype, NULL_RTX);
2154 #else
2155 INIT_CUMULATIVE_ARGS (all->args_so_far, fntype, NULL_RTX,
2156 current_function_decl, -1);
2157 #endif
2159 #ifdef REG_PARM_STACK_SPACE
2160 all->reg_parm_stack_space = REG_PARM_STACK_SPACE (current_function_decl);
2161 #endif
2164 /* If ARGS contains entries with complex types, split the entry into two
2165 entries of the component type. Return a new list of substitutions are
2166 needed, else the old list. */
2168 static void
2169 split_complex_args (VEC(tree, heap) **args)
2171 unsigned i;
2172 tree p;
2174 for (i = 0; VEC_iterate (tree, *args, i, p); ++i)
2176 tree type = TREE_TYPE (p);
2177 if (TREE_CODE (type) == COMPLEX_TYPE
2178 && targetm.calls.split_complex_arg (type))
2180 tree decl;
2181 tree subtype = TREE_TYPE (type);
2182 bool addressable = TREE_ADDRESSABLE (p);
2184 /* Rewrite the PARM_DECL's type with its component. */
2185 p = copy_node (p);
2186 TREE_TYPE (p) = subtype;
2187 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
2188 DECL_MODE (p) = VOIDmode;
2189 DECL_SIZE (p) = NULL;
2190 DECL_SIZE_UNIT (p) = NULL;
2191 /* If this arg must go in memory, put it in a pseudo here.
2192 We can't allow it to go in memory as per normal parms,
2193 because the usual place might not have the imag part
2194 adjacent to the real part. */
2195 DECL_ARTIFICIAL (p) = addressable;
2196 DECL_IGNORED_P (p) = addressable;
2197 TREE_ADDRESSABLE (p) = 0;
2198 layout_decl (p, 0);
2199 VEC_replace (tree, *args, i, p);
2201 /* Build a second synthetic decl. */
2202 decl = build_decl (EXPR_LOCATION (p),
2203 PARM_DECL, NULL_TREE, subtype);
2204 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
2205 DECL_ARTIFICIAL (decl) = addressable;
2206 DECL_IGNORED_P (decl) = addressable;
2207 layout_decl (decl, 0);
2208 VEC_safe_insert (tree, heap, *args, ++i, decl);
2213 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
2214 the hidden struct return argument, and (abi willing) complex args.
2215 Return the new parameter list. */
2217 static VEC(tree, heap) *
2218 assign_parms_augmented_arg_list (struct assign_parm_data_all *all)
2220 tree fndecl = current_function_decl;
2221 tree fntype = TREE_TYPE (fndecl);
2222 VEC(tree, heap) *fnargs = NULL;
2223 tree arg;
2225 for (arg = DECL_ARGUMENTS (fndecl); arg; arg = DECL_CHAIN (arg))
2226 VEC_safe_push (tree, heap, fnargs, arg);
2228 all->orig_fnargs = DECL_ARGUMENTS (fndecl);
2230 /* If struct value address is treated as the first argument, make it so. */
2231 if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
2232 && ! cfun->returns_pcc_struct
2233 && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
2235 tree type = build_pointer_type (TREE_TYPE (fntype));
2236 tree decl;
2238 decl = build_decl (DECL_SOURCE_LOCATION (fndecl),
2239 PARM_DECL, NULL_TREE, type);
2240 DECL_ARG_TYPE (decl) = type;
2241 DECL_ARTIFICIAL (decl) = 1;
2242 DECL_IGNORED_P (decl) = 1;
2244 DECL_CHAIN (decl) = all->orig_fnargs;
2245 all->orig_fnargs = decl;
2246 VEC_safe_insert (tree, heap, fnargs, 0, decl);
2248 all->function_result_decl = decl;
2251 /* If the target wants to split complex arguments into scalars, do so. */
2252 if (targetm.calls.split_complex_arg)
2253 split_complex_args (&fnargs);
2255 return fnargs;
2258 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2259 data for the parameter. Incorporate ABI specifics such as pass-by-
2260 reference and type promotion. */
2262 static void
2263 assign_parm_find_data_types (struct assign_parm_data_all *all, tree parm,
2264 struct assign_parm_data_one *data)
2266 tree nominal_type, passed_type;
2267 enum machine_mode nominal_mode, passed_mode, promoted_mode;
2268 int unsignedp;
2270 memset (data, 0, sizeof (*data));
2272 /* NAMED_ARG is a misnomer. We really mean 'non-variadic'. */
2273 if (!cfun->stdarg)
2274 data->named_arg = 1; /* No variadic parms. */
2275 else if (DECL_CHAIN (parm))
2276 data->named_arg = 1; /* Not the last non-variadic parm. */
2277 else if (targetm.calls.strict_argument_naming (&all->args_so_far))
2278 data->named_arg = 1; /* Only variadic ones are unnamed. */
2279 else
2280 data->named_arg = 0; /* Treat as variadic. */
2282 nominal_type = TREE_TYPE (parm);
2283 passed_type = DECL_ARG_TYPE (parm);
2285 /* Look out for errors propagating this far. Also, if the parameter's
2286 type is void then its value doesn't matter. */
2287 if (TREE_TYPE (parm) == error_mark_node
2288 /* This can happen after weird syntax errors
2289 or if an enum type is defined among the parms. */
2290 || TREE_CODE (parm) != PARM_DECL
2291 || passed_type == NULL
2292 || VOID_TYPE_P (nominal_type))
2294 nominal_type = passed_type = void_type_node;
2295 nominal_mode = passed_mode = promoted_mode = VOIDmode;
2296 goto egress;
2299 /* Find mode of arg as it is passed, and mode of arg as it should be
2300 during execution of this function. */
2301 passed_mode = TYPE_MODE (passed_type);
2302 nominal_mode = TYPE_MODE (nominal_type);
2304 /* If the parm is to be passed as a transparent union or record, use the
2305 type of the first field for the tests below. We have already verified
2306 that the modes are the same. */
2307 if ((TREE_CODE (passed_type) == UNION_TYPE
2308 || TREE_CODE (passed_type) == RECORD_TYPE)
2309 && TYPE_TRANSPARENT_AGGR (passed_type))
2310 passed_type = TREE_TYPE (first_field (passed_type));
2312 /* See if this arg was passed by invisible reference. */
2313 if (pass_by_reference (&all->args_so_far, passed_mode,
2314 passed_type, data->named_arg))
2316 passed_type = nominal_type = build_pointer_type (passed_type);
2317 data->passed_pointer = true;
2318 passed_mode = nominal_mode = Pmode;
2321 /* Find mode as it is passed by the ABI. */
2322 unsignedp = TYPE_UNSIGNED (passed_type);
2323 promoted_mode = promote_function_mode (passed_type, passed_mode, &unsignedp,
2324 TREE_TYPE (current_function_decl), 0);
2326 egress:
2327 data->nominal_type = nominal_type;
2328 data->passed_type = passed_type;
2329 data->nominal_mode = nominal_mode;
2330 data->passed_mode = passed_mode;
2331 data->promoted_mode = promoted_mode;
2334 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2336 static void
2337 assign_parms_setup_varargs (struct assign_parm_data_all *all,
2338 struct assign_parm_data_one *data, bool no_rtl)
2340 int varargs_pretend_bytes = 0;
2342 targetm.calls.setup_incoming_varargs (&all->args_so_far,
2343 data->promoted_mode,
2344 data->passed_type,
2345 &varargs_pretend_bytes, no_rtl);
2347 /* If the back-end has requested extra stack space, record how much is
2348 needed. Do not change pretend_args_size otherwise since it may be
2349 nonzero from an earlier partial argument. */
2350 if (varargs_pretend_bytes > 0)
2351 all->pretend_args_size = varargs_pretend_bytes;
2354 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2355 the incoming location of the current parameter. */
2357 static void
2358 assign_parm_find_entry_rtl (struct assign_parm_data_all *all,
2359 struct assign_parm_data_one *data)
2361 HOST_WIDE_INT pretend_bytes = 0;
2362 rtx entry_parm;
2363 bool in_regs;
2365 if (data->promoted_mode == VOIDmode)
2367 data->entry_parm = data->stack_parm = const0_rtx;
2368 return;
2371 entry_parm = targetm.calls.function_incoming_arg (&all->args_so_far,
2372 data->promoted_mode,
2373 data->passed_type,
2374 data->named_arg);
2376 if (entry_parm == 0)
2377 data->promoted_mode = data->passed_mode;
2379 /* Determine parm's home in the stack, in case it arrives in the stack
2380 or we should pretend it did. Compute the stack position and rtx where
2381 the argument arrives and its size.
2383 There is one complexity here: If this was a parameter that would
2384 have been passed in registers, but wasn't only because it is
2385 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2386 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2387 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2388 as it was the previous time. */
2389 in_regs = entry_parm != 0;
2390 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2391 in_regs = true;
2392 #endif
2393 if (!in_regs && !data->named_arg)
2395 if (targetm.calls.pretend_outgoing_varargs_named (&all->args_so_far))
2397 rtx tem;
2398 tem = targetm.calls.function_incoming_arg (&all->args_so_far,
2399 data->promoted_mode,
2400 data->passed_type, true);
2401 in_regs = tem != NULL;
2405 /* If this parameter was passed both in registers and in the stack, use
2406 the copy on the stack. */
2407 if (targetm.calls.must_pass_in_stack (data->promoted_mode,
2408 data->passed_type))
2409 entry_parm = 0;
2411 if (entry_parm)
2413 int partial;
2415 partial = targetm.calls.arg_partial_bytes (&all->args_so_far,
2416 data->promoted_mode,
2417 data->passed_type,
2418 data->named_arg);
2419 data->partial = partial;
2421 /* The caller might already have allocated stack space for the
2422 register parameters. */
2423 if (partial != 0 && all->reg_parm_stack_space == 0)
2425 /* Part of this argument is passed in registers and part
2426 is passed on the stack. Ask the prologue code to extend
2427 the stack part so that we can recreate the full value.
2429 PRETEND_BYTES is the size of the registers we need to store.
2430 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2431 stack space that the prologue should allocate.
2433 Internally, gcc assumes that the argument pointer is aligned
2434 to STACK_BOUNDARY bits. This is used both for alignment
2435 optimizations (see init_emit) and to locate arguments that are
2436 aligned to more than PARM_BOUNDARY bits. We must preserve this
2437 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2438 a stack boundary. */
2440 /* We assume at most one partial arg, and it must be the first
2441 argument on the stack. */
2442 gcc_assert (!all->extra_pretend_bytes && !all->pretend_args_size);
2444 pretend_bytes = partial;
2445 all->pretend_args_size = CEIL_ROUND (pretend_bytes, STACK_BYTES);
2447 /* We want to align relative to the actual stack pointer, so
2448 don't include this in the stack size until later. */
2449 all->extra_pretend_bytes = all->pretend_args_size;
2453 locate_and_pad_parm (data->promoted_mode, data->passed_type, in_regs,
2454 entry_parm ? data->partial : 0, current_function_decl,
2455 &all->stack_args_size, &data->locate);
2457 /* Update parm_stack_boundary if this parameter is passed in the
2458 stack. */
2459 if (!in_regs && crtl->parm_stack_boundary < data->locate.boundary)
2460 crtl->parm_stack_boundary = data->locate.boundary;
2462 /* Adjust offsets to include the pretend args. */
2463 pretend_bytes = all->extra_pretend_bytes - pretend_bytes;
2464 data->locate.slot_offset.constant += pretend_bytes;
2465 data->locate.offset.constant += pretend_bytes;
2467 data->entry_parm = entry_parm;
2470 /* A subroutine of assign_parms. If there is actually space on the stack
2471 for this parm, count it in stack_args_size and return true. */
2473 static bool
2474 assign_parm_is_stack_parm (struct assign_parm_data_all *all,
2475 struct assign_parm_data_one *data)
2477 /* Trivially true if we've no incoming register. */
2478 if (data->entry_parm == NULL)
2480 /* Also true if we're partially in registers and partially not,
2481 since we've arranged to drop the entire argument on the stack. */
2482 else if (data->partial != 0)
2484 /* Also true if the target says that it's passed in both registers
2485 and on the stack. */
2486 else if (GET_CODE (data->entry_parm) == PARALLEL
2487 && XEXP (XVECEXP (data->entry_parm, 0, 0), 0) == NULL_RTX)
2489 /* Also true if the target says that there's stack allocated for
2490 all register parameters. */
2491 else if (all->reg_parm_stack_space > 0)
2493 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2494 else
2495 return false;
2497 all->stack_args_size.constant += data->locate.size.constant;
2498 if (data->locate.size.var)
2499 ADD_PARM_SIZE (all->stack_args_size, data->locate.size.var);
2501 return true;
2504 /* A subroutine of assign_parms. Given that this parameter is allocated
2505 stack space by the ABI, find it. */
2507 static void
2508 assign_parm_find_stack_rtl (tree parm, struct assign_parm_data_one *data)
2510 rtx offset_rtx, stack_parm;
2511 unsigned int align, boundary;
2513 /* If we're passing this arg using a reg, make its stack home the
2514 aligned stack slot. */
2515 if (data->entry_parm)
2516 offset_rtx = ARGS_SIZE_RTX (data->locate.slot_offset);
2517 else
2518 offset_rtx = ARGS_SIZE_RTX (data->locate.offset);
2520 stack_parm = crtl->args.internal_arg_pointer;
2521 if (offset_rtx != const0_rtx)
2522 stack_parm = gen_rtx_PLUS (Pmode, stack_parm, offset_rtx);
2523 stack_parm = gen_rtx_MEM (data->promoted_mode, stack_parm);
2525 if (!data->passed_pointer)
2527 set_mem_attributes (stack_parm, parm, 1);
2528 /* set_mem_attributes could set MEM_SIZE to the passed mode's size,
2529 while promoted mode's size is needed. */
2530 if (data->promoted_mode != BLKmode
2531 && data->promoted_mode != DECL_MODE (parm))
2533 set_mem_size (stack_parm,
2534 GEN_INT (GET_MODE_SIZE (data->promoted_mode)));
2535 if (MEM_EXPR (stack_parm) && MEM_OFFSET (stack_parm))
2537 int offset = subreg_lowpart_offset (DECL_MODE (parm),
2538 data->promoted_mode);
2539 if (offset)
2540 set_mem_offset (stack_parm,
2541 plus_constant (MEM_OFFSET (stack_parm),
2542 -offset));
2547 boundary = data->locate.boundary;
2548 align = BITS_PER_UNIT;
2550 /* If we're padding upward, we know that the alignment of the slot
2551 is FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2552 intentionally forcing upward padding. Otherwise we have to come
2553 up with a guess at the alignment based on OFFSET_RTX. */
2554 if (data->locate.where_pad != downward || data->entry_parm)
2555 align = boundary;
2556 else if (CONST_INT_P (offset_rtx))
2558 align = INTVAL (offset_rtx) * BITS_PER_UNIT | boundary;
2559 align = align & -align;
2561 set_mem_align (stack_parm, align);
2563 if (data->entry_parm)
2564 set_reg_attrs_for_parm (data->entry_parm, stack_parm);
2566 data->stack_parm = stack_parm;
2569 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2570 always valid and contiguous. */
2572 static void
2573 assign_parm_adjust_entry_rtl (struct assign_parm_data_one *data)
2575 rtx entry_parm = data->entry_parm;
2576 rtx stack_parm = data->stack_parm;
2578 /* If this parm was passed part in regs and part in memory, pretend it
2579 arrived entirely in memory by pushing the register-part onto the stack.
2580 In the special case of a DImode or DFmode that is split, we could put
2581 it together in a pseudoreg directly, but for now that's not worth
2582 bothering with. */
2583 if (data->partial != 0)
2585 /* Handle calls that pass values in multiple non-contiguous
2586 locations. The Irix 6 ABI has examples of this. */
2587 if (GET_CODE (entry_parm) == PARALLEL)
2588 emit_group_store (validize_mem (stack_parm), entry_parm,
2589 data->passed_type,
2590 int_size_in_bytes (data->passed_type));
2591 else
2593 gcc_assert (data->partial % UNITS_PER_WORD == 0);
2594 move_block_from_reg (REGNO (entry_parm), validize_mem (stack_parm),
2595 data->partial / UNITS_PER_WORD);
2598 entry_parm = stack_parm;
2601 /* If we didn't decide this parm came in a register, by default it came
2602 on the stack. */
2603 else if (entry_parm == NULL)
2604 entry_parm = stack_parm;
2606 /* When an argument is passed in multiple locations, we can't make use
2607 of this information, but we can save some copying if the whole argument
2608 is passed in a single register. */
2609 else if (GET_CODE (entry_parm) == PARALLEL
2610 && data->nominal_mode != BLKmode
2611 && data->passed_mode != BLKmode)
2613 size_t i, len = XVECLEN (entry_parm, 0);
2615 for (i = 0; i < len; i++)
2616 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
2617 && REG_P (XEXP (XVECEXP (entry_parm, 0, i), 0))
2618 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
2619 == data->passed_mode)
2620 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
2622 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
2623 break;
2627 data->entry_parm = entry_parm;
2630 /* A subroutine of assign_parms. Reconstitute any values which were
2631 passed in multiple registers and would fit in a single register. */
2633 static void
2634 assign_parm_remove_parallels (struct assign_parm_data_one *data)
2636 rtx entry_parm = data->entry_parm;
2638 /* Convert the PARALLEL to a REG of the same mode as the parallel.
2639 This can be done with register operations rather than on the
2640 stack, even if we will store the reconstituted parameter on the
2641 stack later. */
2642 if (GET_CODE (entry_parm) == PARALLEL && GET_MODE (entry_parm) != BLKmode)
2644 rtx parmreg = gen_reg_rtx (GET_MODE (entry_parm));
2645 emit_group_store (parmreg, entry_parm, data->passed_type,
2646 GET_MODE_SIZE (GET_MODE (entry_parm)));
2647 entry_parm = parmreg;
2650 data->entry_parm = entry_parm;
2653 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2654 always valid and properly aligned. */
2656 static void
2657 assign_parm_adjust_stack_rtl (struct assign_parm_data_one *data)
2659 rtx stack_parm = data->stack_parm;
2661 /* If we can't trust the parm stack slot to be aligned enough for its
2662 ultimate type, don't use that slot after entry. We'll make another
2663 stack slot, if we need one. */
2664 if (stack_parm
2665 && ((STRICT_ALIGNMENT
2666 && GET_MODE_ALIGNMENT (data->nominal_mode) > MEM_ALIGN (stack_parm))
2667 || (data->nominal_type
2668 && TYPE_ALIGN (data->nominal_type) > MEM_ALIGN (stack_parm)
2669 && MEM_ALIGN (stack_parm) < PREFERRED_STACK_BOUNDARY)))
2670 stack_parm = NULL;
2672 /* If parm was passed in memory, and we need to convert it on entry,
2673 don't store it back in that same slot. */
2674 else if (data->entry_parm == stack_parm
2675 && data->nominal_mode != BLKmode
2676 && data->nominal_mode != data->passed_mode)
2677 stack_parm = NULL;
2679 /* If stack protection is in effect for this function, don't leave any
2680 pointers in their passed stack slots. */
2681 else if (crtl->stack_protect_guard
2682 && (flag_stack_protect == 2
2683 || data->passed_pointer
2684 || POINTER_TYPE_P (data->nominal_type)))
2685 stack_parm = NULL;
2687 data->stack_parm = stack_parm;
2690 /* A subroutine of assign_parms. Return true if the current parameter
2691 should be stored as a BLKmode in the current frame. */
2693 static bool
2694 assign_parm_setup_block_p (struct assign_parm_data_one *data)
2696 if (data->nominal_mode == BLKmode)
2697 return true;
2698 if (GET_MODE (data->entry_parm) == BLKmode)
2699 return true;
2701 #ifdef BLOCK_REG_PADDING
2702 /* Only assign_parm_setup_block knows how to deal with register arguments
2703 that are padded at the least significant end. */
2704 if (REG_P (data->entry_parm)
2705 && GET_MODE_SIZE (data->promoted_mode) < UNITS_PER_WORD
2706 && (BLOCK_REG_PADDING (data->passed_mode, data->passed_type, 1)
2707 == (BYTES_BIG_ENDIAN ? upward : downward)))
2708 return true;
2709 #endif
2711 return false;
2714 /* A subroutine of assign_parms. Arrange for the parameter to be
2715 present and valid in DATA->STACK_RTL. */
2717 static void
2718 assign_parm_setup_block (struct assign_parm_data_all *all,
2719 tree parm, struct assign_parm_data_one *data)
2721 rtx entry_parm = data->entry_parm;
2722 rtx stack_parm = data->stack_parm;
2723 HOST_WIDE_INT size;
2724 HOST_WIDE_INT size_stored;
2726 if (GET_CODE (entry_parm) == PARALLEL)
2727 entry_parm = emit_group_move_into_temps (entry_parm);
2729 size = int_size_in_bytes (data->passed_type);
2730 size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
2731 if (stack_parm == 0)
2733 DECL_ALIGN (parm) = MAX (DECL_ALIGN (parm), BITS_PER_WORD);
2734 stack_parm = assign_stack_local (BLKmode, size_stored,
2735 DECL_ALIGN (parm));
2736 if (GET_MODE_SIZE (GET_MODE (entry_parm)) == size)
2737 PUT_MODE (stack_parm, GET_MODE (entry_parm));
2738 set_mem_attributes (stack_parm, parm, 1);
2741 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2742 calls that pass values in multiple non-contiguous locations. */
2743 if (REG_P (entry_parm) || GET_CODE (entry_parm) == PARALLEL)
2745 rtx mem;
2747 /* Note that we will be storing an integral number of words.
2748 So we have to be careful to ensure that we allocate an
2749 integral number of words. We do this above when we call
2750 assign_stack_local if space was not allocated in the argument
2751 list. If it was, this will not work if PARM_BOUNDARY is not
2752 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2753 if it becomes a problem. Exception is when BLKmode arrives
2754 with arguments not conforming to word_mode. */
2756 if (data->stack_parm == 0)
2758 else if (GET_CODE (entry_parm) == PARALLEL)
2760 else
2761 gcc_assert (!size || !(PARM_BOUNDARY % BITS_PER_WORD));
2763 mem = validize_mem (stack_parm);
2765 /* Handle values in multiple non-contiguous locations. */
2766 if (GET_CODE (entry_parm) == PARALLEL)
2768 push_to_sequence2 (all->first_conversion_insn,
2769 all->last_conversion_insn);
2770 emit_group_store (mem, entry_parm, data->passed_type, size);
2771 all->first_conversion_insn = get_insns ();
2772 all->last_conversion_insn = get_last_insn ();
2773 end_sequence ();
2776 else if (size == 0)
2779 /* If SIZE is that of a mode no bigger than a word, just use
2780 that mode's store operation. */
2781 else if (size <= UNITS_PER_WORD)
2783 enum machine_mode mode
2784 = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
2786 if (mode != BLKmode
2787 #ifdef BLOCK_REG_PADDING
2788 && (size == UNITS_PER_WORD
2789 || (BLOCK_REG_PADDING (mode, data->passed_type, 1)
2790 != (BYTES_BIG_ENDIAN ? upward : downward)))
2791 #endif
2794 rtx reg;
2796 /* We are really truncating a word_mode value containing
2797 SIZE bytes into a value of mode MODE. If such an
2798 operation requires no actual instructions, we can refer
2799 to the value directly in mode MODE, otherwise we must
2800 start with the register in word_mode and explicitly
2801 convert it. */
2802 if (TRULY_NOOP_TRUNCATION (size * BITS_PER_UNIT, BITS_PER_WORD))
2803 reg = gen_rtx_REG (mode, REGNO (entry_parm));
2804 else
2806 reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
2807 reg = convert_to_mode (mode, copy_to_reg (reg), 1);
2809 emit_move_insn (change_address (mem, mode, 0), reg);
2812 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
2813 machine must be aligned to the left before storing
2814 to memory. Note that the previous test doesn't
2815 handle all cases (e.g. SIZE == 3). */
2816 else if (size != UNITS_PER_WORD
2817 #ifdef BLOCK_REG_PADDING
2818 && (BLOCK_REG_PADDING (mode, data->passed_type, 1)
2819 == downward)
2820 #else
2821 && BYTES_BIG_ENDIAN
2822 #endif
2825 rtx tem, x;
2826 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2827 rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
2829 x = expand_shift (LSHIFT_EXPR, word_mode, reg,
2830 build_int_cst (NULL_TREE, by),
2831 NULL_RTX, 1);
2832 tem = change_address (mem, word_mode, 0);
2833 emit_move_insn (tem, x);
2835 else
2836 move_block_from_reg (REGNO (entry_parm), mem,
2837 size_stored / UNITS_PER_WORD);
2839 else
2840 move_block_from_reg (REGNO (entry_parm), mem,
2841 size_stored / UNITS_PER_WORD);
2843 else if (data->stack_parm == 0)
2845 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
2846 emit_block_move (stack_parm, data->entry_parm, GEN_INT (size),
2847 BLOCK_OP_NORMAL);
2848 all->first_conversion_insn = get_insns ();
2849 all->last_conversion_insn = get_last_insn ();
2850 end_sequence ();
2853 data->stack_parm = stack_parm;
2854 SET_DECL_RTL (parm, stack_parm);
2857 /* A subroutine of assign_parm_setup_reg, called through note_stores.
2858 This collects sets and clobbers of hard registers in a HARD_REG_SET,
2859 which is pointed to by DATA. */
2860 static void
2861 record_hard_reg_sets (rtx x, const_rtx pat ATTRIBUTE_UNUSED, void *data)
2863 HARD_REG_SET *pset = (HARD_REG_SET *)data;
2864 if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER)
2866 int nregs = hard_regno_nregs[REGNO (x)][GET_MODE (x)];
2867 while (nregs-- > 0)
2868 SET_HARD_REG_BIT (*pset, REGNO (x) + nregs);
2872 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
2873 parameter. Get it there. Perform all ABI specified conversions. */
2875 static void
2876 assign_parm_setup_reg (struct assign_parm_data_all *all, tree parm,
2877 struct assign_parm_data_one *data)
2879 rtx parmreg, validated_mem;
2880 rtx equiv_stack_parm;
2881 enum machine_mode promoted_nominal_mode;
2882 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (parm));
2883 bool did_conversion = false;
2884 bool need_conversion, moved;
2886 /* Store the parm in a pseudoregister during the function, but we may
2887 need to do it in a wider mode. Using 2 here makes the result
2888 consistent with promote_decl_mode and thus expand_expr_real_1. */
2889 promoted_nominal_mode
2890 = promote_function_mode (data->nominal_type, data->nominal_mode, &unsignedp,
2891 TREE_TYPE (current_function_decl), 2);
2893 parmreg = gen_reg_rtx (promoted_nominal_mode);
2895 if (!DECL_ARTIFICIAL (parm))
2896 mark_user_reg (parmreg);
2898 /* If this was an item that we received a pointer to,
2899 set DECL_RTL appropriately. */
2900 if (data->passed_pointer)
2902 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data->passed_type)), parmreg);
2903 set_mem_attributes (x, parm, 1);
2904 SET_DECL_RTL (parm, x);
2906 else
2907 SET_DECL_RTL (parm, parmreg);
2909 assign_parm_remove_parallels (data);
2911 /* Copy the value into the register, thus bridging between
2912 assign_parm_find_data_types and expand_expr_real_1. */
2914 equiv_stack_parm = data->stack_parm;
2915 validated_mem = validize_mem (data->entry_parm);
2917 need_conversion = (data->nominal_mode != data->passed_mode
2918 || promoted_nominal_mode != data->promoted_mode);
2919 moved = false;
2921 if (need_conversion
2922 && GET_MODE_CLASS (data->nominal_mode) == MODE_INT
2923 && data->nominal_mode == data->passed_mode
2924 && data->nominal_mode == GET_MODE (data->entry_parm))
2926 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
2927 mode, by the caller. We now have to convert it to
2928 NOMINAL_MODE, if different. However, PARMREG may be in
2929 a different mode than NOMINAL_MODE if it is being stored
2930 promoted.
2932 If ENTRY_PARM is a hard register, it might be in a register
2933 not valid for operating in its mode (e.g., an odd-numbered
2934 register for a DFmode). In that case, moves are the only
2935 thing valid, so we can't do a convert from there. This
2936 occurs when the calling sequence allow such misaligned
2937 usages.
2939 In addition, the conversion may involve a call, which could
2940 clobber parameters which haven't been copied to pseudo
2941 registers yet.
2943 First, we try to emit an insn which performs the necessary
2944 conversion. We verify that this insn does not clobber any
2945 hard registers. */
2947 enum insn_code icode;
2948 rtx op0, op1;
2950 icode = can_extend_p (promoted_nominal_mode, data->passed_mode,
2951 unsignedp);
2953 op0 = parmreg;
2954 op1 = validated_mem;
2955 if (icode != CODE_FOR_nothing
2956 && insn_data[icode].operand[0].predicate (op0, promoted_nominal_mode)
2957 && insn_data[icode].operand[1].predicate (op1, data->passed_mode))
2959 enum rtx_code code = unsignedp ? ZERO_EXTEND : SIGN_EXTEND;
2960 rtx insn, insns;
2961 HARD_REG_SET hardregs;
2963 start_sequence ();
2964 insn = gen_extend_insn (op0, op1, promoted_nominal_mode,
2965 data->passed_mode, unsignedp);
2966 emit_insn (insn);
2967 insns = get_insns ();
2969 moved = true;
2970 CLEAR_HARD_REG_SET (hardregs);
2971 for (insn = insns; insn && moved; insn = NEXT_INSN (insn))
2973 if (INSN_P (insn))
2974 note_stores (PATTERN (insn), record_hard_reg_sets,
2975 &hardregs);
2976 if (!hard_reg_set_empty_p (hardregs))
2977 moved = false;
2980 end_sequence ();
2982 if (moved)
2984 emit_insn (insns);
2985 if (equiv_stack_parm != NULL_RTX)
2986 equiv_stack_parm = gen_rtx_fmt_e (code, GET_MODE (parmreg),
2987 equiv_stack_parm);
2992 if (moved)
2993 /* Nothing to do. */
2995 else if (need_conversion)
2997 /* We did not have an insn to convert directly, or the sequence
2998 generated appeared unsafe. We must first copy the parm to a
2999 pseudo reg, and save the conversion until after all
3000 parameters have been moved. */
3002 int save_tree_used;
3003 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
3005 emit_move_insn (tempreg, validated_mem);
3007 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
3008 tempreg = convert_to_mode (data->nominal_mode, tempreg, unsignedp);
3010 if (GET_CODE (tempreg) == SUBREG
3011 && GET_MODE (tempreg) == data->nominal_mode
3012 && REG_P (SUBREG_REG (tempreg))
3013 && data->nominal_mode == data->passed_mode
3014 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (data->entry_parm)
3015 && GET_MODE_SIZE (GET_MODE (tempreg))
3016 < GET_MODE_SIZE (GET_MODE (data->entry_parm)))
3018 /* The argument is already sign/zero extended, so note it
3019 into the subreg. */
3020 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
3021 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
3024 /* TREE_USED gets set erroneously during expand_assignment. */
3025 save_tree_used = TREE_USED (parm);
3026 expand_assignment (parm, make_tree (data->nominal_type, tempreg), false);
3027 TREE_USED (parm) = save_tree_used;
3028 all->first_conversion_insn = get_insns ();
3029 all->last_conversion_insn = get_last_insn ();
3030 end_sequence ();
3032 did_conversion = true;
3034 else
3035 emit_move_insn (parmreg, validated_mem);
3037 /* If we were passed a pointer but the actual value can safely live
3038 in a register, put it in one. */
3039 if (data->passed_pointer
3040 && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
3041 /* If by-reference argument was promoted, demote it. */
3042 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
3043 || use_register_for_decl (parm)))
3045 /* We can't use nominal_mode, because it will have been set to
3046 Pmode above. We must use the actual mode of the parm. */
3047 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
3048 mark_user_reg (parmreg);
3050 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
3052 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
3053 int unsigned_p = TYPE_UNSIGNED (TREE_TYPE (parm));
3055 push_to_sequence2 (all->first_conversion_insn,
3056 all->last_conversion_insn);
3057 emit_move_insn (tempreg, DECL_RTL (parm));
3058 tempreg = convert_to_mode (GET_MODE (parmreg), tempreg, unsigned_p);
3059 emit_move_insn (parmreg, tempreg);
3060 all->first_conversion_insn = get_insns ();
3061 all->last_conversion_insn = get_last_insn ();
3062 end_sequence ();
3064 did_conversion = true;
3066 else
3067 emit_move_insn (parmreg, DECL_RTL (parm));
3069 SET_DECL_RTL (parm, parmreg);
3071 /* STACK_PARM is the pointer, not the parm, and PARMREG is
3072 now the parm. */
3073 data->stack_parm = NULL;
3076 /* Mark the register as eliminable if we did no conversion and it was
3077 copied from memory at a fixed offset, and the arg pointer was not
3078 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
3079 offset formed an invalid address, such memory-equivalences as we
3080 make here would screw up life analysis for it. */
3081 if (data->nominal_mode == data->passed_mode
3082 && !did_conversion
3083 && data->stack_parm != 0
3084 && MEM_P (data->stack_parm)
3085 && data->locate.offset.var == 0
3086 && reg_mentioned_p (virtual_incoming_args_rtx,
3087 XEXP (data->stack_parm, 0)))
3089 rtx linsn = get_last_insn ();
3090 rtx sinsn, set;
3092 /* Mark complex types separately. */
3093 if (GET_CODE (parmreg) == CONCAT)
3095 enum machine_mode submode
3096 = GET_MODE_INNER (GET_MODE (parmreg));
3097 int regnor = REGNO (XEXP (parmreg, 0));
3098 int regnoi = REGNO (XEXP (parmreg, 1));
3099 rtx stackr = adjust_address_nv (data->stack_parm, submode, 0);
3100 rtx stacki = adjust_address_nv (data->stack_parm, submode,
3101 GET_MODE_SIZE (submode));
3103 /* Scan backwards for the set of the real and
3104 imaginary parts. */
3105 for (sinsn = linsn; sinsn != 0;
3106 sinsn = prev_nonnote_insn (sinsn))
3108 set = single_set (sinsn);
3109 if (set == 0)
3110 continue;
3112 if (SET_DEST (set) == regno_reg_rtx [regnoi])
3113 set_unique_reg_note (sinsn, REG_EQUIV, stacki);
3114 else if (SET_DEST (set) == regno_reg_rtx [regnor])
3115 set_unique_reg_note (sinsn, REG_EQUIV, stackr);
3118 else if ((set = single_set (linsn)) != 0
3119 && SET_DEST (set) == parmreg)
3120 set_unique_reg_note (linsn, REG_EQUIV, equiv_stack_parm);
3123 /* For pointer data type, suggest pointer register. */
3124 if (POINTER_TYPE_P (TREE_TYPE (parm)))
3125 mark_reg_pointer (parmreg,
3126 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
3129 /* A subroutine of assign_parms. Allocate stack space to hold the current
3130 parameter. Get it there. Perform all ABI specified conversions. */
3132 static void
3133 assign_parm_setup_stack (struct assign_parm_data_all *all, tree parm,
3134 struct assign_parm_data_one *data)
3136 /* Value must be stored in the stack slot STACK_PARM during function
3137 execution. */
3138 bool to_conversion = false;
3140 assign_parm_remove_parallels (data);
3142 if (data->promoted_mode != data->nominal_mode)
3144 /* Conversion is required. */
3145 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
3147 emit_move_insn (tempreg, validize_mem (data->entry_parm));
3149 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
3150 to_conversion = true;
3152 data->entry_parm = convert_to_mode (data->nominal_mode, tempreg,
3153 TYPE_UNSIGNED (TREE_TYPE (parm)));
3155 if (data->stack_parm)
3157 int offset = subreg_lowpart_offset (data->nominal_mode,
3158 GET_MODE (data->stack_parm));
3159 /* ??? This may need a big-endian conversion on sparc64. */
3160 data->stack_parm
3161 = adjust_address (data->stack_parm, data->nominal_mode, 0);
3162 if (offset && MEM_OFFSET (data->stack_parm))
3163 set_mem_offset (data->stack_parm,
3164 plus_constant (MEM_OFFSET (data->stack_parm),
3165 offset));
3169 if (data->entry_parm != data->stack_parm)
3171 rtx src, dest;
3173 if (data->stack_parm == 0)
3175 int align = STACK_SLOT_ALIGNMENT (data->passed_type,
3176 GET_MODE (data->entry_parm),
3177 TYPE_ALIGN (data->passed_type));
3178 data->stack_parm
3179 = assign_stack_local (GET_MODE (data->entry_parm),
3180 GET_MODE_SIZE (GET_MODE (data->entry_parm)),
3181 align);
3182 set_mem_attributes (data->stack_parm, parm, 1);
3185 dest = validize_mem (data->stack_parm);
3186 src = validize_mem (data->entry_parm);
3188 if (MEM_P (src))
3190 /* Use a block move to handle potentially misaligned entry_parm. */
3191 if (!to_conversion)
3192 push_to_sequence2 (all->first_conversion_insn,
3193 all->last_conversion_insn);
3194 to_conversion = true;
3196 emit_block_move (dest, src,
3197 GEN_INT (int_size_in_bytes (data->passed_type)),
3198 BLOCK_OP_NORMAL);
3200 else
3201 emit_move_insn (dest, src);
3204 if (to_conversion)
3206 all->first_conversion_insn = get_insns ();
3207 all->last_conversion_insn = get_last_insn ();
3208 end_sequence ();
3211 SET_DECL_RTL (parm, data->stack_parm);
3214 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
3215 undo the frobbing that we did in assign_parms_augmented_arg_list. */
3217 static void
3218 assign_parms_unsplit_complex (struct assign_parm_data_all *all,
3219 VEC(tree, heap) *fnargs)
3221 tree parm;
3222 tree orig_fnargs = all->orig_fnargs;
3223 unsigned i = 0;
3225 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm), ++i)
3227 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE
3228 && targetm.calls.split_complex_arg (TREE_TYPE (parm)))
3230 rtx tmp, real, imag;
3231 enum machine_mode inner = GET_MODE_INNER (DECL_MODE (parm));
3233 real = DECL_RTL (VEC_index (tree, fnargs, i));
3234 imag = DECL_RTL (VEC_index (tree, fnargs, i + 1));
3235 if (inner != GET_MODE (real))
3237 real = gen_lowpart_SUBREG (inner, real);
3238 imag = gen_lowpart_SUBREG (inner, imag);
3241 if (TREE_ADDRESSABLE (parm))
3243 rtx rmem, imem;
3244 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (parm));
3245 int align = STACK_SLOT_ALIGNMENT (TREE_TYPE (parm),
3246 DECL_MODE (parm),
3247 TYPE_ALIGN (TREE_TYPE (parm)));
3249 /* split_complex_arg put the real and imag parts in
3250 pseudos. Move them to memory. */
3251 tmp = assign_stack_local (DECL_MODE (parm), size, align);
3252 set_mem_attributes (tmp, parm, 1);
3253 rmem = adjust_address_nv (tmp, inner, 0);
3254 imem = adjust_address_nv (tmp, inner, GET_MODE_SIZE (inner));
3255 push_to_sequence2 (all->first_conversion_insn,
3256 all->last_conversion_insn);
3257 emit_move_insn (rmem, real);
3258 emit_move_insn (imem, imag);
3259 all->first_conversion_insn = get_insns ();
3260 all->last_conversion_insn = get_last_insn ();
3261 end_sequence ();
3263 else
3264 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3265 SET_DECL_RTL (parm, tmp);
3267 real = DECL_INCOMING_RTL (VEC_index (tree, fnargs, i));
3268 imag = DECL_INCOMING_RTL (VEC_index (tree, fnargs, i + 1));
3269 if (inner != GET_MODE (real))
3271 real = gen_lowpart_SUBREG (inner, real);
3272 imag = gen_lowpart_SUBREG (inner, imag);
3274 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3275 set_decl_incoming_rtl (parm, tmp, false);
3276 i++;
3281 /* Assign RTL expressions to the function's parameters. This may involve
3282 copying them into registers and using those registers as the DECL_RTL. */
3284 static void
3285 assign_parms (tree fndecl)
3287 struct assign_parm_data_all all;
3288 tree parm;
3289 VEC(tree, heap) *fnargs;
3290 unsigned i;
3292 crtl->args.internal_arg_pointer
3293 = targetm.calls.internal_arg_pointer ();
3295 assign_parms_initialize_all (&all);
3296 fnargs = assign_parms_augmented_arg_list (&all);
3298 for (i = 0; VEC_iterate (tree, fnargs, i, parm); ++i)
3300 struct assign_parm_data_one data;
3302 /* Extract the type of PARM; adjust it according to ABI. */
3303 assign_parm_find_data_types (&all, parm, &data);
3305 /* Early out for errors and void parameters. */
3306 if (data.passed_mode == VOIDmode)
3308 SET_DECL_RTL (parm, const0_rtx);
3309 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
3310 continue;
3313 /* Estimate stack alignment from parameter alignment. */
3314 if (SUPPORTS_STACK_ALIGNMENT)
3316 unsigned int align = FUNCTION_ARG_BOUNDARY (data.promoted_mode,
3317 data.passed_type);
3318 align = MINIMUM_ALIGNMENT (data.passed_type, data.promoted_mode,
3319 align);
3320 if (TYPE_ALIGN (data.nominal_type) > align)
3321 align = MINIMUM_ALIGNMENT (data.nominal_type,
3322 TYPE_MODE (data.nominal_type),
3323 TYPE_ALIGN (data.nominal_type));
3324 if (crtl->stack_alignment_estimated < align)
3326 gcc_assert (!crtl->stack_realign_processed);
3327 crtl->stack_alignment_estimated = align;
3331 if (cfun->stdarg && !DECL_CHAIN (parm))
3332 assign_parms_setup_varargs (&all, &data, false);
3334 /* Find out where the parameter arrives in this function. */
3335 assign_parm_find_entry_rtl (&all, &data);
3337 /* Find out where stack space for this parameter might be. */
3338 if (assign_parm_is_stack_parm (&all, &data))
3340 assign_parm_find_stack_rtl (parm, &data);
3341 assign_parm_adjust_entry_rtl (&data);
3344 /* Record permanently how this parm was passed. */
3345 set_decl_incoming_rtl (parm, data.entry_parm, data.passed_pointer);
3347 /* Update info on where next arg arrives in registers. */
3348 targetm.calls.function_arg_advance (&all.args_so_far, data.promoted_mode,
3349 data.passed_type, data.named_arg);
3351 assign_parm_adjust_stack_rtl (&data);
3353 if (assign_parm_setup_block_p (&data))
3354 assign_parm_setup_block (&all, parm, &data);
3355 else if (data.passed_pointer || use_register_for_decl (parm))
3356 assign_parm_setup_reg (&all, parm, &data);
3357 else
3358 assign_parm_setup_stack (&all, parm, &data);
3361 if (targetm.calls.split_complex_arg)
3362 assign_parms_unsplit_complex (&all, fnargs);
3364 VEC_free (tree, heap, fnargs);
3366 /* Output all parameter conversion instructions (possibly including calls)
3367 now that all parameters have been copied out of hard registers. */
3368 emit_insn (all.first_conversion_insn);
3370 /* Estimate reload stack alignment from scalar return mode. */
3371 if (SUPPORTS_STACK_ALIGNMENT)
3373 if (DECL_RESULT (fndecl))
3375 tree type = TREE_TYPE (DECL_RESULT (fndecl));
3376 enum machine_mode mode = TYPE_MODE (type);
3378 if (mode != BLKmode
3379 && mode != VOIDmode
3380 && !AGGREGATE_TYPE_P (type))
3382 unsigned int align = GET_MODE_ALIGNMENT (mode);
3383 if (crtl->stack_alignment_estimated < align)
3385 gcc_assert (!crtl->stack_realign_processed);
3386 crtl->stack_alignment_estimated = align;
3392 /* If we are receiving a struct value address as the first argument, set up
3393 the RTL for the function result. As this might require code to convert
3394 the transmitted address to Pmode, we do this here to ensure that possible
3395 preliminary conversions of the address have been emitted already. */
3396 if (all.function_result_decl)
3398 tree result = DECL_RESULT (current_function_decl);
3399 rtx addr = DECL_RTL (all.function_result_decl);
3400 rtx x;
3402 if (DECL_BY_REFERENCE (result))
3403 x = addr;
3404 else
3406 addr = convert_memory_address (Pmode, addr);
3407 x = gen_rtx_MEM (DECL_MODE (result), addr);
3408 set_mem_attributes (x, result, 1);
3410 SET_DECL_RTL (result, x);
3413 /* We have aligned all the args, so add space for the pretend args. */
3414 crtl->args.pretend_args_size = all.pretend_args_size;
3415 all.stack_args_size.constant += all.extra_pretend_bytes;
3416 crtl->args.size = all.stack_args_size.constant;
3418 /* Adjust function incoming argument size for alignment and
3419 minimum length. */
3421 #ifdef REG_PARM_STACK_SPACE
3422 crtl->args.size = MAX (crtl->args.size,
3423 REG_PARM_STACK_SPACE (fndecl));
3424 #endif
3426 crtl->args.size = CEIL_ROUND (crtl->args.size,
3427 PARM_BOUNDARY / BITS_PER_UNIT);
3429 #ifdef ARGS_GROW_DOWNWARD
3430 crtl->args.arg_offset_rtx
3431 = (all.stack_args_size.var == 0 ? GEN_INT (-all.stack_args_size.constant)
3432 : expand_expr (size_diffop (all.stack_args_size.var,
3433 size_int (-all.stack_args_size.constant)),
3434 NULL_RTX, VOIDmode, EXPAND_NORMAL));
3435 #else
3436 crtl->args.arg_offset_rtx = ARGS_SIZE_RTX (all.stack_args_size);
3437 #endif
3439 /* See how many bytes, if any, of its args a function should try to pop
3440 on return. */
3442 crtl->args.pops_args = targetm.calls.return_pops_args (fndecl,
3443 TREE_TYPE (fndecl),
3444 crtl->args.size);
3446 /* For stdarg.h function, save info about
3447 regs and stack space used by the named args. */
3449 crtl->args.info = all.args_so_far;
3451 /* Set the rtx used for the function return value. Put this in its
3452 own variable so any optimizers that need this information don't have
3453 to include tree.h. Do this here so it gets done when an inlined
3454 function gets output. */
3456 crtl->return_rtx
3457 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
3458 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
3460 /* If scalar return value was computed in a pseudo-reg, or was a named
3461 return value that got dumped to the stack, copy that to the hard
3462 return register. */
3463 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
3465 tree decl_result = DECL_RESULT (fndecl);
3466 rtx decl_rtl = DECL_RTL (decl_result);
3468 if (REG_P (decl_rtl)
3469 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
3470 : DECL_REGISTER (decl_result))
3472 rtx real_decl_rtl;
3474 real_decl_rtl = targetm.calls.function_value (TREE_TYPE (decl_result),
3475 fndecl, true);
3476 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
3477 /* The delay slot scheduler assumes that crtl->return_rtx
3478 holds the hard register containing the return value, not a
3479 temporary pseudo. */
3480 crtl->return_rtx = real_decl_rtl;
3485 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3486 For all seen types, gimplify their sizes. */
3488 static tree
3489 gimplify_parm_type (tree *tp, int *walk_subtrees, void *data)
3491 tree t = *tp;
3493 *walk_subtrees = 0;
3494 if (TYPE_P (t))
3496 if (POINTER_TYPE_P (t))
3497 *walk_subtrees = 1;
3498 else if (TYPE_SIZE (t) && !TREE_CONSTANT (TYPE_SIZE (t))
3499 && !TYPE_SIZES_GIMPLIFIED (t))
3501 gimplify_type_sizes (t, (gimple_seq *) data);
3502 *walk_subtrees = 1;
3506 return NULL;
3509 /* Gimplify the parameter list for current_function_decl. This involves
3510 evaluating SAVE_EXPRs of variable sized parameters and generating code
3511 to implement callee-copies reference parameters. Returns a sequence of
3512 statements to add to the beginning of the function. */
3514 gimple_seq
3515 gimplify_parameters (void)
3517 struct assign_parm_data_all all;
3518 tree parm;
3519 gimple_seq stmts = NULL;
3520 VEC(tree, heap) *fnargs;
3521 unsigned i;
3523 assign_parms_initialize_all (&all);
3524 fnargs = assign_parms_augmented_arg_list (&all);
3526 for (i = 0; VEC_iterate (tree, fnargs, i, parm); ++i)
3528 struct assign_parm_data_one data;
3530 /* Extract the type of PARM; adjust it according to ABI. */
3531 assign_parm_find_data_types (&all, parm, &data);
3533 /* Early out for errors and void parameters. */
3534 if (data.passed_mode == VOIDmode || DECL_SIZE (parm) == NULL)
3535 continue;
3537 /* Update info on where next arg arrives in registers. */
3538 targetm.calls.function_arg_advance (&all.args_so_far, data.promoted_mode,
3539 data.passed_type, data.named_arg);
3541 /* ??? Once upon a time variable_size stuffed parameter list
3542 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3543 turned out to be less than manageable in the gimple world.
3544 Now we have to hunt them down ourselves. */
3545 walk_tree_without_duplicates (&data.passed_type,
3546 gimplify_parm_type, &stmts);
3548 if (TREE_CODE (DECL_SIZE_UNIT (parm)) != INTEGER_CST)
3550 gimplify_one_sizepos (&DECL_SIZE (parm), &stmts);
3551 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm), &stmts);
3554 if (data.passed_pointer)
3556 tree type = TREE_TYPE (data.passed_type);
3557 if (reference_callee_copied (&all.args_so_far, TYPE_MODE (type),
3558 type, data.named_arg))
3560 tree local, t;
3562 /* For constant-sized objects, this is trivial; for
3563 variable-sized objects, we have to play games. */
3564 if (TREE_CODE (DECL_SIZE_UNIT (parm)) == INTEGER_CST
3565 && !(flag_stack_check == GENERIC_STACK_CHECK
3566 && compare_tree_int (DECL_SIZE_UNIT (parm),
3567 STACK_CHECK_MAX_VAR_SIZE) > 0))
3569 local = create_tmp_var (type, get_name (parm));
3570 DECL_IGNORED_P (local) = 0;
3571 /* If PARM was addressable, move that flag over
3572 to the local copy, as its address will be taken,
3573 not the PARMs. */
3574 if (TREE_ADDRESSABLE (parm))
3576 TREE_ADDRESSABLE (parm) = 0;
3577 TREE_ADDRESSABLE (local) = 1;
3580 else
3582 tree ptr_type, addr;
3584 ptr_type = build_pointer_type (type);
3585 addr = create_tmp_var (ptr_type, get_name (parm));
3586 DECL_IGNORED_P (addr) = 0;
3587 local = build_fold_indirect_ref (addr);
3589 t = built_in_decls[BUILT_IN_ALLOCA];
3590 t = build_call_expr (t, 1, DECL_SIZE_UNIT (parm));
3591 t = fold_convert (ptr_type, t);
3592 t = build2 (MODIFY_EXPR, TREE_TYPE (addr), addr, t);
3593 gimplify_and_add (t, &stmts);
3596 gimplify_assign (local, parm, &stmts);
3598 SET_DECL_VALUE_EXPR (parm, local);
3599 DECL_HAS_VALUE_EXPR_P (parm) = 1;
3604 VEC_free (tree, heap, fnargs);
3606 return stmts;
3609 /* Compute the size and offset from the start of the stacked arguments for a
3610 parm passed in mode PASSED_MODE and with type TYPE.
3612 INITIAL_OFFSET_PTR points to the current offset into the stacked
3613 arguments.
3615 The starting offset and size for this parm are returned in
3616 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3617 nonzero, the offset is that of stack slot, which is returned in
3618 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3619 padding required from the initial offset ptr to the stack slot.
3621 IN_REGS is nonzero if the argument will be passed in registers. It will
3622 never be set if REG_PARM_STACK_SPACE is not defined.
3624 FNDECL is the function in which the argument was defined.
3626 There are two types of rounding that are done. The first, controlled by
3627 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
3628 list to be aligned to the specific boundary (in bits). This rounding
3629 affects the initial and starting offsets, but not the argument size.
3631 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3632 optionally rounds the size of the parm to PARM_BOUNDARY. The
3633 initial offset is not affected by this rounding, while the size always
3634 is and the starting offset may be. */
3636 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3637 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3638 callers pass in the total size of args so far as
3639 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
3641 void
3642 locate_and_pad_parm (enum machine_mode passed_mode, tree type, int in_regs,
3643 int partial, tree fndecl ATTRIBUTE_UNUSED,
3644 struct args_size *initial_offset_ptr,
3645 struct locate_and_pad_arg_data *locate)
3647 tree sizetree;
3648 enum direction where_pad;
3649 unsigned int boundary;
3650 int reg_parm_stack_space = 0;
3651 int part_size_in_regs;
3653 #ifdef REG_PARM_STACK_SPACE
3654 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
3656 /* If we have found a stack parm before we reach the end of the
3657 area reserved for registers, skip that area. */
3658 if (! in_regs)
3660 if (reg_parm_stack_space > 0)
3662 if (initial_offset_ptr->var)
3664 initial_offset_ptr->var
3665 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
3666 ssize_int (reg_parm_stack_space));
3667 initial_offset_ptr->constant = 0;
3669 else if (initial_offset_ptr->constant < reg_parm_stack_space)
3670 initial_offset_ptr->constant = reg_parm_stack_space;
3673 #endif /* REG_PARM_STACK_SPACE */
3675 part_size_in_regs = (reg_parm_stack_space == 0 ? partial : 0);
3677 sizetree
3678 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
3679 where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
3680 boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
3681 locate->where_pad = where_pad;
3683 /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT. */
3684 if (boundary > MAX_SUPPORTED_STACK_ALIGNMENT)
3685 boundary = MAX_SUPPORTED_STACK_ALIGNMENT;
3687 locate->boundary = boundary;
3689 if (SUPPORTS_STACK_ALIGNMENT)
3691 /* stack_alignment_estimated can't change after stack has been
3692 realigned. */
3693 if (crtl->stack_alignment_estimated < boundary)
3695 if (!crtl->stack_realign_processed)
3696 crtl->stack_alignment_estimated = boundary;
3697 else
3699 /* If stack is realigned and stack alignment value
3700 hasn't been finalized, it is OK not to increase
3701 stack_alignment_estimated. The bigger alignment
3702 requirement is recorded in stack_alignment_needed
3703 below. */
3704 gcc_assert (!crtl->stack_realign_finalized
3705 && crtl->stack_realign_needed);
3710 /* Remember if the outgoing parameter requires extra alignment on the
3711 calling function side. */
3712 if (crtl->stack_alignment_needed < boundary)
3713 crtl->stack_alignment_needed = boundary;
3714 if (crtl->preferred_stack_boundary < boundary)
3715 crtl->preferred_stack_boundary = boundary;
3717 #ifdef ARGS_GROW_DOWNWARD
3718 locate->slot_offset.constant = -initial_offset_ptr->constant;
3719 if (initial_offset_ptr->var)
3720 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
3721 initial_offset_ptr->var);
3724 tree s2 = sizetree;
3725 if (where_pad != none
3726 && (!host_integerp (sizetree, 1)
3727 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
3728 s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
3729 SUB_PARM_SIZE (locate->slot_offset, s2);
3732 locate->slot_offset.constant += part_size_in_regs;
3734 if (!in_regs
3735 #ifdef REG_PARM_STACK_SPACE
3736 || REG_PARM_STACK_SPACE (fndecl) > 0
3737 #endif
3739 pad_to_arg_alignment (&locate->slot_offset, boundary,
3740 &locate->alignment_pad);
3742 locate->size.constant = (-initial_offset_ptr->constant
3743 - locate->slot_offset.constant);
3744 if (initial_offset_ptr->var)
3745 locate->size.var = size_binop (MINUS_EXPR,
3746 size_binop (MINUS_EXPR,
3747 ssize_int (0),
3748 initial_offset_ptr->var),
3749 locate->slot_offset.var);
3751 /* Pad_below needs the pre-rounded size to know how much to pad
3752 below. */
3753 locate->offset = locate->slot_offset;
3754 if (where_pad == downward)
3755 pad_below (&locate->offset, passed_mode, sizetree);
3757 #else /* !ARGS_GROW_DOWNWARD */
3758 if (!in_regs
3759 #ifdef REG_PARM_STACK_SPACE
3760 || REG_PARM_STACK_SPACE (fndecl) > 0
3761 #endif
3763 pad_to_arg_alignment (initial_offset_ptr, boundary,
3764 &locate->alignment_pad);
3765 locate->slot_offset = *initial_offset_ptr;
3767 #ifdef PUSH_ROUNDING
3768 if (passed_mode != BLKmode)
3769 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
3770 #endif
3772 /* Pad_below needs the pre-rounded size to know how much to pad below
3773 so this must be done before rounding up. */
3774 locate->offset = locate->slot_offset;
3775 if (where_pad == downward)
3776 pad_below (&locate->offset, passed_mode, sizetree);
3778 if (where_pad != none
3779 && (!host_integerp (sizetree, 1)
3780 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
3781 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
3783 ADD_PARM_SIZE (locate->size, sizetree);
3785 locate->size.constant -= part_size_in_regs;
3786 #endif /* ARGS_GROW_DOWNWARD */
3788 #ifdef FUNCTION_ARG_OFFSET
3789 locate->offset.constant += FUNCTION_ARG_OFFSET (passed_mode, type);
3790 #endif
3793 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
3794 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
3796 static void
3797 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
3798 struct args_size *alignment_pad)
3800 tree save_var = NULL_TREE;
3801 HOST_WIDE_INT save_constant = 0;
3802 int boundary_in_bytes = boundary / BITS_PER_UNIT;
3803 HOST_WIDE_INT sp_offset = STACK_POINTER_OFFSET;
3805 #ifdef SPARC_STACK_BOUNDARY_HACK
3806 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
3807 the real alignment of %sp. However, when it does this, the
3808 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
3809 if (SPARC_STACK_BOUNDARY_HACK)
3810 sp_offset = 0;
3811 #endif
3813 if (boundary > PARM_BOUNDARY)
3815 save_var = offset_ptr->var;
3816 save_constant = offset_ptr->constant;
3819 alignment_pad->var = NULL_TREE;
3820 alignment_pad->constant = 0;
3822 if (boundary > BITS_PER_UNIT)
3824 if (offset_ptr->var)
3826 tree sp_offset_tree = ssize_int (sp_offset);
3827 tree offset = size_binop (PLUS_EXPR,
3828 ARGS_SIZE_TREE (*offset_ptr),
3829 sp_offset_tree);
3830 #ifdef ARGS_GROW_DOWNWARD
3831 tree rounded = round_down (offset, boundary / BITS_PER_UNIT);
3832 #else
3833 tree rounded = round_up (offset, boundary / BITS_PER_UNIT);
3834 #endif
3836 offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
3837 /* ARGS_SIZE_TREE includes constant term. */
3838 offset_ptr->constant = 0;
3839 if (boundary > PARM_BOUNDARY)
3840 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
3841 save_var);
3843 else
3845 offset_ptr->constant = -sp_offset +
3846 #ifdef ARGS_GROW_DOWNWARD
3847 FLOOR_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
3848 #else
3849 CEIL_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
3850 #endif
3851 if (boundary > PARM_BOUNDARY)
3852 alignment_pad->constant = offset_ptr->constant - save_constant;
3857 static void
3858 pad_below (struct args_size *offset_ptr, enum machine_mode passed_mode, tree sizetree)
3860 if (passed_mode != BLKmode)
3862 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
3863 offset_ptr->constant
3864 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
3865 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
3866 - GET_MODE_SIZE (passed_mode));
3868 else
3870 if (TREE_CODE (sizetree) != INTEGER_CST
3871 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
3873 /* Round the size up to multiple of PARM_BOUNDARY bits. */
3874 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
3875 /* Add it in. */
3876 ADD_PARM_SIZE (*offset_ptr, s2);
3877 SUB_PARM_SIZE (*offset_ptr, sizetree);
3883 /* True if register REGNO was alive at a place where `setjmp' was
3884 called and was set more than once or is an argument. Such regs may
3885 be clobbered by `longjmp'. */
3887 static bool
3888 regno_clobbered_at_setjmp (bitmap setjmp_crosses, int regno)
3890 /* There appear to be cases where some local vars never reach the
3891 backend but have bogus regnos. */
3892 if (regno >= max_reg_num ())
3893 return false;
3895 return ((REG_N_SETS (regno) > 1
3896 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR), regno))
3897 && REGNO_REG_SET_P (setjmp_crosses, regno));
3900 /* Walk the tree of blocks describing the binding levels within a
3901 function and warn about variables the might be killed by setjmp or
3902 vfork. This is done after calling flow_analysis before register
3903 allocation since that will clobber the pseudo-regs to hard
3904 regs. */
3906 static void
3907 setjmp_vars_warning (bitmap setjmp_crosses, tree block)
3909 tree decl, sub;
3911 for (decl = BLOCK_VARS (block); decl; decl = DECL_CHAIN (decl))
3913 if (TREE_CODE (decl) == VAR_DECL
3914 && DECL_RTL_SET_P (decl)
3915 && REG_P (DECL_RTL (decl))
3916 && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
3917 warning (OPT_Wclobbered, "variable %q+D might be clobbered by"
3918 " %<longjmp%> or %<vfork%>", decl);
3921 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = BLOCK_CHAIN (sub))
3922 setjmp_vars_warning (setjmp_crosses, sub);
3925 /* Do the appropriate part of setjmp_vars_warning
3926 but for arguments instead of local variables. */
3928 static void
3929 setjmp_args_warning (bitmap setjmp_crosses)
3931 tree decl;
3932 for (decl = DECL_ARGUMENTS (current_function_decl);
3933 decl; decl = DECL_CHAIN (decl))
3934 if (DECL_RTL (decl) != 0
3935 && REG_P (DECL_RTL (decl))
3936 && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
3937 warning (OPT_Wclobbered,
3938 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
3939 decl);
3942 /* Generate warning messages for variables live across setjmp. */
3944 void
3945 generate_setjmp_warnings (void)
3947 bitmap setjmp_crosses = regstat_get_setjmp_crosses ();
3949 if (n_basic_blocks == NUM_FIXED_BLOCKS
3950 || bitmap_empty_p (setjmp_crosses))
3951 return;
3953 setjmp_vars_warning (setjmp_crosses, DECL_INITIAL (current_function_decl));
3954 setjmp_args_warning (setjmp_crosses);
3958 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
3959 and create duplicate blocks. */
3960 /* ??? Need an option to either create block fragments or to create
3961 abstract origin duplicates of a source block. It really depends
3962 on what optimization has been performed. */
3964 void
3965 reorder_blocks (void)
3967 tree block = DECL_INITIAL (current_function_decl);
3968 VEC(tree,heap) *block_stack;
3970 if (block == NULL_TREE)
3971 return;
3973 block_stack = VEC_alloc (tree, heap, 10);
3975 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
3976 clear_block_marks (block);
3978 /* Prune the old trees away, so that they don't get in the way. */
3979 BLOCK_SUBBLOCKS (block) = NULL_TREE;
3980 BLOCK_CHAIN (block) = NULL_TREE;
3982 /* Recreate the block tree from the note nesting. */
3983 reorder_blocks_1 (get_insns (), block, &block_stack);
3984 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
3986 VEC_free (tree, heap, block_stack);
3989 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
3991 void
3992 clear_block_marks (tree block)
3994 while (block)
3996 TREE_ASM_WRITTEN (block) = 0;
3997 clear_block_marks (BLOCK_SUBBLOCKS (block));
3998 block = BLOCK_CHAIN (block);
4002 static void
4003 reorder_blocks_1 (rtx insns, tree current_block, VEC(tree,heap) **p_block_stack)
4005 rtx insn;
4007 for (insn = insns; insn; insn = NEXT_INSN (insn))
4009 if (NOTE_P (insn))
4011 if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_BEG)
4013 tree block = NOTE_BLOCK (insn);
4014 tree origin;
4016 origin = (BLOCK_FRAGMENT_ORIGIN (block)
4017 ? BLOCK_FRAGMENT_ORIGIN (block)
4018 : block);
4020 /* If we have seen this block before, that means it now
4021 spans multiple address regions. Create a new fragment. */
4022 if (TREE_ASM_WRITTEN (block))
4024 tree new_block = copy_node (block);
4026 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
4027 BLOCK_FRAGMENT_CHAIN (new_block)
4028 = BLOCK_FRAGMENT_CHAIN (origin);
4029 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
4031 NOTE_BLOCK (insn) = new_block;
4032 block = new_block;
4035 BLOCK_SUBBLOCKS (block) = 0;
4036 TREE_ASM_WRITTEN (block) = 1;
4037 /* When there's only one block for the entire function,
4038 current_block == block and we mustn't do this, it
4039 will cause infinite recursion. */
4040 if (block != current_block)
4042 if (block != origin)
4043 gcc_assert (BLOCK_SUPERCONTEXT (origin) == current_block);
4045 BLOCK_SUPERCONTEXT (block) = current_block;
4046 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
4047 BLOCK_SUBBLOCKS (current_block) = block;
4048 current_block = origin;
4050 VEC_safe_push (tree, heap, *p_block_stack, block);
4052 else if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_END)
4054 NOTE_BLOCK (insn) = VEC_pop (tree, *p_block_stack);
4055 BLOCK_SUBBLOCKS (current_block)
4056 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
4057 current_block = BLOCK_SUPERCONTEXT (current_block);
4063 /* Reverse the order of elements in the chain T of blocks,
4064 and return the new head of the chain (old last element). */
4066 tree
4067 blocks_nreverse (tree t)
4069 tree prev = 0, decl, next;
4070 for (decl = t; decl; decl = next)
4072 next = BLOCK_CHAIN (decl);
4073 BLOCK_CHAIN (decl) = prev;
4074 prev = decl;
4076 return prev;
4079 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
4080 non-NULL, list them all into VECTOR, in a depth-first preorder
4081 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
4082 blocks. */
4084 static int
4085 all_blocks (tree block, tree *vector)
4087 int n_blocks = 0;
4089 while (block)
4091 TREE_ASM_WRITTEN (block) = 0;
4093 /* Record this block. */
4094 if (vector)
4095 vector[n_blocks] = block;
4097 ++n_blocks;
4099 /* Record the subblocks, and their subblocks... */
4100 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
4101 vector ? vector + n_blocks : 0);
4102 block = BLOCK_CHAIN (block);
4105 return n_blocks;
4108 /* Return a vector containing all the blocks rooted at BLOCK. The
4109 number of elements in the vector is stored in N_BLOCKS_P. The
4110 vector is dynamically allocated; it is the caller's responsibility
4111 to call `free' on the pointer returned. */
4113 static tree *
4114 get_block_vector (tree block, int *n_blocks_p)
4116 tree *block_vector;
4118 *n_blocks_p = all_blocks (block, NULL);
4119 block_vector = XNEWVEC (tree, *n_blocks_p);
4120 all_blocks (block, block_vector);
4122 return block_vector;
4125 static GTY(()) int next_block_index = 2;
4127 /* Set BLOCK_NUMBER for all the blocks in FN. */
4129 void
4130 number_blocks (tree fn)
4132 int i;
4133 int n_blocks;
4134 tree *block_vector;
4136 /* For SDB and XCOFF debugging output, we start numbering the blocks
4137 from 1 within each function, rather than keeping a running
4138 count. */
4139 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
4140 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
4141 next_block_index = 1;
4142 #endif
4144 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
4146 /* The top-level BLOCK isn't numbered at all. */
4147 for (i = 1; i < n_blocks; ++i)
4148 /* We number the blocks from two. */
4149 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
4151 free (block_vector);
4153 return;
4156 /* If VAR is present in a subblock of BLOCK, return the subblock. */
4158 DEBUG_FUNCTION tree
4159 debug_find_var_in_block_tree (tree var, tree block)
4161 tree t;
4163 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
4164 if (t == var)
4165 return block;
4167 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
4169 tree ret = debug_find_var_in_block_tree (var, t);
4170 if (ret)
4171 return ret;
4174 return NULL_TREE;
4177 /* Keep track of whether we're in a dummy function context. If we are,
4178 we don't want to invoke the set_current_function hook, because we'll
4179 get into trouble if the hook calls target_reinit () recursively or
4180 when the initial initialization is not yet complete. */
4182 static bool in_dummy_function;
4184 /* Invoke the target hook when setting cfun. Update the optimization options
4185 if the function uses different options than the default. */
4187 static void
4188 invoke_set_current_function_hook (tree fndecl)
4190 if (!in_dummy_function)
4192 tree opts = ((fndecl)
4193 ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl)
4194 : optimization_default_node);
4196 if (!opts)
4197 opts = optimization_default_node;
4199 /* Change optimization options if needed. */
4200 if (optimization_current_node != opts)
4202 optimization_current_node = opts;
4203 cl_optimization_restore (TREE_OPTIMIZATION (opts));
4206 targetm.set_current_function (fndecl);
4210 /* cfun should never be set directly; use this function. */
4212 void
4213 set_cfun (struct function *new_cfun)
4215 if (cfun != new_cfun)
4217 cfun = new_cfun;
4218 invoke_set_current_function_hook (new_cfun ? new_cfun->decl : NULL_TREE);
4222 /* Initialized with NOGC, making this poisonous to the garbage collector. */
4224 static VEC(function_p,heap) *cfun_stack;
4226 /* Push the current cfun onto the stack, and set cfun to new_cfun. */
4228 void
4229 push_cfun (struct function *new_cfun)
4231 VEC_safe_push (function_p, heap, cfun_stack, cfun);
4232 set_cfun (new_cfun);
4235 /* Pop cfun from the stack. */
4237 void
4238 pop_cfun (void)
4240 struct function *new_cfun = VEC_pop (function_p, cfun_stack);
4241 set_cfun (new_cfun);
4244 /* Return value of funcdef and increase it. */
4246 get_next_funcdef_no (void)
4248 return funcdef_no++;
4251 /* Allocate a function structure for FNDECL and set its contents
4252 to the defaults. Set cfun to the newly-allocated object.
4253 Some of the helper functions invoked during initialization assume
4254 that cfun has already been set. Therefore, assign the new object
4255 directly into cfun and invoke the back end hook explicitly at the
4256 very end, rather than initializing a temporary and calling set_cfun
4257 on it.
4259 ABSTRACT_P is true if this is a function that will never be seen by
4260 the middle-end. Such functions are front-end concepts (like C++
4261 function templates) that do not correspond directly to functions
4262 placed in object files. */
4264 void
4265 allocate_struct_function (tree fndecl, bool abstract_p)
4267 tree result;
4268 tree fntype = fndecl ? TREE_TYPE (fndecl) : NULL_TREE;
4270 cfun = ggc_alloc_cleared_function ();
4272 init_eh_for_function ();
4274 if (init_machine_status)
4275 cfun->machine = (*init_machine_status) ();
4277 #ifdef OVERRIDE_ABI_FORMAT
4278 OVERRIDE_ABI_FORMAT (fndecl);
4279 #endif
4281 invoke_set_current_function_hook (fndecl);
4283 if (fndecl != NULL_TREE)
4285 DECL_STRUCT_FUNCTION (fndecl) = cfun;
4286 cfun->decl = fndecl;
4287 current_function_funcdef_no = get_next_funcdef_no ();
4289 result = DECL_RESULT (fndecl);
4290 if (!abstract_p && aggregate_value_p (result, fndecl))
4292 #ifdef PCC_STATIC_STRUCT_RETURN
4293 cfun->returns_pcc_struct = 1;
4294 #endif
4295 cfun->returns_struct = 1;
4298 cfun->stdarg
4299 = (fntype
4300 && TYPE_ARG_TYPES (fntype) != 0
4301 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4302 != void_type_node));
4304 /* Assume all registers in stdarg functions need to be saved. */
4305 cfun->va_list_gpr_size = VA_LIST_MAX_GPR_SIZE;
4306 cfun->va_list_fpr_size = VA_LIST_MAX_FPR_SIZE;
4308 /* ??? This could be set on a per-function basis by the front-end
4309 but is this worth the hassle? */
4310 cfun->can_throw_non_call_exceptions = flag_non_call_exceptions;
4314 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
4315 instead of just setting it. */
4317 void
4318 push_struct_function (tree fndecl)
4320 VEC_safe_push (function_p, heap, cfun_stack, cfun);
4321 allocate_struct_function (fndecl, false);
4324 /* Reset crtl and other non-struct-function variables to defaults as
4325 appropriate for emitting rtl at the start of a function. */
4327 static void
4328 prepare_function_start (void)
4330 gcc_assert (!crtl->emit.x_last_insn);
4331 init_temp_slots ();
4332 init_emit ();
4333 init_varasm_status ();
4334 init_expr ();
4335 default_rtl_profile ();
4337 cse_not_expected = ! optimize;
4339 /* Caller save not needed yet. */
4340 caller_save_needed = 0;
4342 /* We haven't done register allocation yet. */
4343 reg_renumber = 0;
4345 /* Indicate that we have not instantiated virtual registers yet. */
4346 virtuals_instantiated = 0;
4348 /* Indicate that we want CONCATs now. */
4349 generating_concat_p = 1;
4351 /* Indicate we have no need of a frame pointer yet. */
4352 frame_pointer_needed = 0;
4355 /* Initialize the rtl expansion mechanism so that we can do simple things
4356 like generate sequences. This is used to provide a context during global
4357 initialization of some passes. You must call expand_dummy_function_end
4358 to exit this context. */
4360 void
4361 init_dummy_function_start (void)
4363 gcc_assert (!in_dummy_function);
4364 in_dummy_function = true;
4365 push_struct_function (NULL_TREE);
4366 prepare_function_start ();
4369 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
4370 and initialize static variables for generating RTL for the statements
4371 of the function. */
4373 void
4374 init_function_start (tree subr)
4376 if (subr && DECL_STRUCT_FUNCTION (subr))
4377 set_cfun (DECL_STRUCT_FUNCTION (subr));
4378 else
4379 allocate_struct_function (subr, false);
4380 prepare_function_start ();
4382 /* Warn if this value is an aggregate type,
4383 regardless of which calling convention we are using for it. */
4384 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
4385 warning (OPT_Waggregate_return, "function returns an aggregate");
4388 /* Make sure all values used by the optimization passes have sane defaults. */
4389 unsigned int
4390 init_function_for_compilation (void)
4392 reg_renumber = 0;
4393 return 0;
4396 struct rtl_opt_pass pass_init_function =
4399 RTL_PASS,
4400 "*init_function", /* name */
4401 NULL, /* gate */
4402 init_function_for_compilation, /* execute */
4403 NULL, /* sub */
4404 NULL, /* next */
4405 0, /* static_pass_number */
4406 TV_NONE, /* tv_id */
4407 0, /* properties_required */
4408 0, /* properties_provided */
4409 0, /* properties_destroyed */
4410 0, /* todo_flags_start */
4411 0 /* todo_flags_finish */
4416 void
4417 expand_main_function (void)
4419 #if (defined(INVOKE__main) \
4420 || (!defined(HAS_INIT_SECTION) \
4421 && !defined(INIT_SECTION_ASM_OP) \
4422 && !defined(INIT_ARRAY_SECTION_ASM_OP)))
4423 emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0);
4424 #endif
4427 /* Expand code to initialize the stack_protect_guard. This is invoked at
4428 the beginning of a function to be protected. */
4430 #ifndef HAVE_stack_protect_set
4431 # define HAVE_stack_protect_set 0
4432 # define gen_stack_protect_set(x,y) (gcc_unreachable (), NULL_RTX)
4433 #endif
4435 void
4436 stack_protect_prologue (void)
4438 tree guard_decl = targetm.stack_protect_guard ();
4439 rtx x, y;
4441 x = expand_normal (crtl->stack_protect_guard);
4442 y = expand_normal (guard_decl);
4444 /* Allow the target to copy from Y to X without leaking Y into a
4445 register. */
4446 if (HAVE_stack_protect_set)
4448 rtx insn = gen_stack_protect_set (x, y);
4449 if (insn)
4451 emit_insn (insn);
4452 return;
4456 /* Otherwise do a straight move. */
4457 emit_move_insn (x, y);
4460 /* Expand code to verify the stack_protect_guard. This is invoked at
4461 the end of a function to be protected. */
4463 #ifndef HAVE_stack_protect_test
4464 # define HAVE_stack_protect_test 0
4465 # define gen_stack_protect_test(x, y, z) (gcc_unreachable (), NULL_RTX)
4466 #endif
4468 void
4469 stack_protect_epilogue (void)
4471 tree guard_decl = targetm.stack_protect_guard ();
4472 rtx label = gen_label_rtx ();
4473 rtx x, y, tmp;
4475 x = expand_normal (crtl->stack_protect_guard);
4476 y = expand_normal (guard_decl);
4478 /* Allow the target to compare Y with X without leaking either into
4479 a register. */
4480 switch (HAVE_stack_protect_test != 0)
4482 case 1:
4483 tmp = gen_stack_protect_test (x, y, label);
4484 if (tmp)
4486 emit_insn (tmp);
4487 break;
4489 /* FALLTHRU */
4491 default:
4492 emit_cmp_and_jump_insns (x, y, EQ, NULL_RTX, ptr_mode, 1, label);
4493 break;
4496 /* The noreturn predictor has been moved to the tree level. The rtl-level
4497 predictors estimate this branch about 20%, which isn't enough to get
4498 things moved out of line. Since this is the only extant case of adding
4499 a noreturn function at the rtl level, it doesn't seem worth doing ought
4500 except adding the prediction by hand. */
4501 tmp = get_last_insn ();
4502 if (JUMP_P (tmp))
4503 predict_insn_def (tmp, PRED_NORETURN, TAKEN);
4505 expand_expr_stmt (targetm.stack_protect_fail ());
4506 emit_label (label);
4509 /* Start the RTL for a new function, and set variables used for
4510 emitting RTL.
4511 SUBR is the FUNCTION_DECL node.
4512 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4513 the function's parameters, which must be run at any return statement. */
4515 void
4516 expand_function_start (tree subr)
4518 /* Make sure volatile mem refs aren't considered
4519 valid operands of arithmetic insns. */
4520 init_recog_no_volatile ();
4522 crtl->profile
4523 = (profile_flag
4524 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
4526 crtl->limit_stack
4527 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
4529 /* Make the label for return statements to jump to. Do not special
4530 case machines with special return instructions -- they will be
4531 handled later during jump, ifcvt, or epilogue creation. */
4532 return_label = gen_label_rtx ();
4534 /* Initialize rtx used to return the value. */
4535 /* Do this before assign_parms so that we copy the struct value address
4536 before any library calls that assign parms might generate. */
4538 /* Decide whether to return the value in memory or in a register. */
4539 if (aggregate_value_p (DECL_RESULT (subr), subr))
4541 /* Returning something that won't go in a register. */
4542 rtx value_address = 0;
4544 #ifdef PCC_STATIC_STRUCT_RETURN
4545 if (cfun->returns_pcc_struct)
4547 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
4548 value_address = assemble_static_space (size);
4550 else
4551 #endif
4553 rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 2);
4554 /* Expect to be passed the address of a place to store the value.
4555 If it is passed as an argument, assign_parms will take care of
4556 it. */
4557 if (sv)
4559 value_address = gen_reg_rtx (Pmode);
4560 emit_move_insn (value_address, sv);
4563 if (value_address)
4565 rtx x = value_address;
4566 if (!DECL_BY_REFERENCE (DECL_RESULT (subr)))
4568 x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), x);
4569 set_mem_attributes (x, DECL_RESULT (subr), 1);
4571 SET_DECL_RTL (DECL_RESULT (subr), x);
4574 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
4575 /* If return mode is void, this decl rtl should not be used. */
4576 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
4577 else
4579 /* Compute the return values into a pseudo reg, which we will copy
4580 into the true return register after the cleanups are done. */
4581 tree return_type = TREE_TYPE (DECL_RESULT (subr));
4582 if (TYPE_MODE (return_type) != BLKmode
4583 && targetm.calls.return_in_msb (return_type))
4584 /* expand_function_end will insert the appropriate padding in
4585 this case. Use the return value's natural (unpadded) mode
4586 within the function proper. */
4587 SET_DECL_RTL (DECL_RESULT (subr),
4588 gen_reg_rtx (TYPE_MODE (return_type)));
4589 else
4591 /* In order to figure out what mode to use for the pseudo, we
4592 figure out what the mode of the eventual return register will
4593 actually be, and use that. */
4594 rtx hard_reg = hard_function_value (return_type, subr, 0, 1);
4596 /* Structures that are returned in registers are not
4597 aggregate_value_p, so we may see a PARALLEL or a REG. */
4598 if (REG_P (hard_reg))
4599 SET_DECL_RTL (DECL_RESULT (subr),
4600 gen_reg_rtx (GET_MODE (hard_reg)));
4601 else
4603 gcc_assert (GET_CODE (hard_reg) == PARALLEL);
4604 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
4608 /* Set DECL_REGISTER flag so that expand_function_end will copy the
4609 result to the real return register(s). */
4610 DECL_REGISTER (DECL_RESULT (subr)) = 1;
4613 /* Initialize rtx for parameters and local variables.
4614 In some cases this requires emitting insns. */
4615 assign_parms (subr);
4617 /* If function gets a static chain arg, store it. */
4618 if (cfun->static_chain_decl)
4620 tree parm = cfun->static_chain_decl;
4621 rtx local, chain, insn;
4623 local = gen_reg_rtx (Pmode);
4624 chain = targetm.calls.static_chain (current_function_decl, true);
4626 set_decl_incoming_rtl (parm, chain, false);
4627 SET_DECL_RTL (parm, local);
4628 mark_reg_pointer (local, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
4630 insn = emit_move_insn (local, chain);
4632 /* Mark the register as eliminable, similar to parameters. */
4633 if (MEM_P (chain)
4634 && reg_mentioned_p (arg_pointer_rtx, XEXP (chain, 0)))
4635 set_unique_reg_note (insn, REG_EQUIV, chain);
4638 /* If the function receives a non-local goto, then store the
4639 bits we need to restore the frame pointer. */
4640 if (cfun->nonlocal_goto_save_area)
4642 tree t_save;
4643 rtx r_save;
4645 /* ??? We need to do this save early. Unfortunately here is
4646 before the frame variable gets declared. Help out... */
4647 tree var = TREE_OPERAND (cfun->nonlocal_goto_save_area, 0);
4648 if (!DECL_RTL_SET_P (var))
4649 expand_decl (var);
4651 t_save = build4 (ARRAY_REF, ptr_type_node,
4652 cfun->nonlocal_goto_save_area,
4653 integer_zero_node, NULL_TREE, NULL_TREE);
4654 r_save = expand_expr (t_save, NULL_RTX, VOIDmode, EXPAND_WRITE);
4655 r_save = convert_memory_address (Pmode, r_save);
4657 emit_move_insn (r_save, targetm.builtin_setjmp_frame_value ());
4658 update_nonlocal_goto_save_area ();
4661 /* The following was moved from init_function_start.
4662 The move is supposed to make sdb output more accurate. */
4663 /* Indicate the beginning of the function body,
4664 as opposed to parm setup. */
4665 emit_note (NOTE_INSN_FUNCTION_BEG);
4667 gcc_assert (NOTE_P (get_last_insn ()));
4669 parm_birth_insn = get_last_insn ();
4671 if (crtl->profile)
4673 #ifdef PROFILE_HOOK
4674 PROFILE_HOOK (current_function_funcdef_no);
4675 #endif
4678 /* After the display initializations is where the stack checking
4679 probe should go. */
4680 if(flag_stack_check)
4681 stack_check_probe_note = emit_note (NOTE_INSN_DELETED);
4683 /* Make sure there is a line number after the function entry setup code. */
4684 force_next_line_note ();
4687 /* Undo the effects of init_dummy_function_start. */
4688 void
4689 expand_dummy_function_end (void)
4691 gcc_assert (in_dummy_function);
4693 /* End any sequences that failed to be closed due to syntax errors. */
4694 while (in_sequence_p ())
4695 end_sequence ();
4697 /* Outside function body, can't compute type's actual size
4698 until next function's body starts. */
4700 free_after_parsing (cfun);
4701 free_after_compilation (cfun);
4702 pop_cfun ();
4703 in_dummy_function = false;
4706 /* Call DOIT for each hard register used as a return value from
4707 the current function. */
4709 void
4710 diddle_return_value (void (*doit) (rtx, void *), void *arg)
4712 rtx outgoing = crtl->return_rtx;
4714 if (! outgoing)
4715 return;
4717 if (REG_P (outgoing))
4718 (*doit) (outgoing, arg);
4719 else if (GET_CODE (outgoing) == PARALLEL)
4721 int i;
4723 for (i = 0; i < XVECLEN (outgoing, 0); i++)
4725 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
4727 if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER)
4728 (*doit) (x, arg);
4733 static void
4734 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
4736 emit_clobber (reg);
4739 void
4740 clobber_return_register (void)
4742 diddle_return_value (do_clobber_return_reg, NULL);
4744 /* In case we do use pseudo to return value, clobber it too. */
4745 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
4747 tree decl_result = DECL_RESULT (current_function_decl);
4748 rtx decl_rtl = DECL_RTL (decl_result);
4749 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
4751 do_clobber_return_reg (decl_rtl, NULL);
4756 static void
4757 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
4759 emit_use (reg);
4762 static void
4763 use_return_register (void)
4765 diddle_return_value (do_use_return_reg, NULL);
4768 /* Possibly warn about unused parameters. */
4769 void
4770 do_warn_unused_parameter (tree fn)
4772 tree decl;
4774 for (decl = DECL_ARGUMENTS (fn);
4775 decl; decl = DECL_CHAIN (decl))
4776 if (!TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
4777 && DECL_NAME (decl) && !DECL_ARTIFICIAL (decl)
4778 && !TREE_NO_WARNING (decl))
4779 warning (OPT_Wunused_parameter, "unused parameter %q+D", decl);
4782 static GTY(()) rtx initial_trampoline;
4784 /* Generate RTL for the end of the current function. */
4786 void
4787 expand_function_end (void)
4789 rtx clobber_after;
4791 /* If arg_pointer_save_area was referenced only from a nested
4792 function, we will not have initialized it yet. Do that now. */
4793 if (arg_pointer_save_area && ! crtl->arg_pointer_save_area_init)
4794 get_arg_pointer_save_area ();
4796 /* If we are doing generic stack checking and this function makes calls,
4797 do a stack probe at the start of the function to ensure we have enough
4798 space for another stack frame. */
4799 if (flag_stack_check == GENERIC_STACK_CHECK)
4801 rtx insn, seq;
4803 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4804 if (CALL_P (insn))
4806 rtx max_frame_size = GEN_INT (STACK_CHECK_MAX_FRAME_SIZE);
4807 start_sequence ();
4808 if (STACK_CHECK_MOVING_SP)
4809 anti_adjust_stack_and_probe (max_frame_size, true);
4810 else
4811 probe_stack_range (STACK_OLD_CHECK_PROTECT, max_frame_size);
4812 seq = get_insns ();
4813 end_sequence ();
4814 emit_insn_before (seq, stack_check_probe_note);
4815 break;
4819 /* End any sequences that failed to be closed due to syntax errors. */
4820 while (in_sequence_p ())
4821 end_sequence ();
4823 clear_pending_stack_adjust ();
4824 do_pending_stack_adjust ();
4826 /* Output a linenumber for the end of the function.
4827 SDB depends on this. */
4828 force_next_line_note ();
4829 set_curr_insn_source_location (input_location);
4831 /* Before the return label (if any), clobber the return
4832 registers so that they are not propagated live to the rest of
4833 the function. This can only happen with functions that drop
4834 through; if there had been a return statement, there would
4835 have either been a return rtx, or a jump to the return label.
4837 We delay actual code generation after the current_function_value_rtx
4838 is computed. */
4839 clobber_after = get_last_insn ();
4841 /* Output the label for the actual return from the function. */
4842 emit_label (return_label);
4844 if (USING_SJLJ_EXCEPTIONS)
4846 /* Let except.c know where it should emit the call to unregister
4847 the function context for sjlj exceptions. */
4848 if (flag_exceptions)
4849 sjlj_emit_function_exit_after (get_last_insn ());
4851 else
4853 /* We want to ensure that instructions that may trap are not
4854 moved into the epilogue by scheduling, because we don't
4855 always emit unwind information for the epilogue. */
4856 if (cfun->can_throw_non_call_exceptions)
4857 emit_insn (gen_blockage ());
4860 /* If this is an implementation of throw, do what's necessary to
4861 communicate between __builtin_eh_return and the epilogue. */
4862 expand_eh_return ();
4864 /* If scalar return value was computed in a pseudo-reg, or was a named
4865 return value that got dumped to the stack, copy that to the hard
4866 return register. */
4867 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
4869 tree decl_result = DECL_RESULT (current_function_decl);
4870 rtx decl_rtl = DECL_RTL (decl_result);
4872 if (REG_P (decl_rtl)
4873 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
4874 : DECL_REGISTER (decl_result))
4876 rtx real_decl_rtl = crtl->return_rtx;
4878 /* This should be set in assign_parms. */
4879 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl));
4881 /* If this is a BLKmode structure being returned in registers,
4882 then use the mode computed in expand_return. Note that if
4883 decl_rtl is memory, then its mode may have been changed,
4884 but that crtl->return_rtx has not. */
4885 if (GET_MODE (real_decl_rtl) == BLKmode)
4886 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
4888 /* If a non-BLKmode return value should be padded at the least
4889 significant end of the register, shift it left by the appropriate
4890 amount. BLKmode results are handled using the group load/store
4891 machinery. */
4892 if (TYPE_MODE (TREE_TYPE (decl_result)) != BLKmode
4893 && targetm.calls.return_in_msb (TREE_TYPE (decl_result)))
4895 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl),
4896 REGNO (real_decl_rtl)),
4897 decl_rtl);
4898 shift_return_value (GET_MODE (decl_rtl), true, real_decl_rtl);
4900 /* If a named return value dumped decl_return to memory, then
4901 we may need to re-do the PROMOTE_MODE signed/unsigned
4902 extension. */
4903 else if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
4905 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (decl_result));
4906 promote_function_mode (TREE_TYPE (decl_result),
4907 GET_MODE (decl_rtl), &unsignedp,
4908 TREE_TYPE (current_function_decl), 1);
4910 convert_move (real_decl_rtl, decl_rtl, unsignedp);
4912 else if (GET_CODE (real_decl_rtl) == PARALLEL)
4914 /* If expand_function_start has created a PARALLEL for decl_rtl,
4915 move the result to the real return registers. Otherwise, do
4916 a group load from decl_rtl for a named return. */
4917 if (GET_CODE (decl_rtl) == PARALLEL)
4918 emit_group_move (real_decl_rtl, decl_rtl);
4919 else
4920 emit_group_load (real_decl_rtl, decl_rtl,
4921 TREE_TYPE (decl_result),
4922 int_size_in_bytes (TREE_TYPE (decl_result)));
4924 /* In the case of complex integer modes smaller than a word, we'll
4925 need to generate some non-trivial bitfield insertions. Do that
4926 on a pseudo and not the hard register. */
4927 else if (GET_CODE (decl_rtl) == CONCAT
4928 && GET_MODE_CLASS (GET_MODE (decl_rtl)) == MODE_COMPLEX_INT
4929 && GET_MODE_BITSIZE (GET_MODE (decl_rtl)) <= BITS_PER_WORD)
4931 int old_generating_concat_p;
4932 rtx tmp;
4934 old_generating_concat_p = generating_concat_p;
4935 generating_concat_p = 0;
4936 tmp = gen_reg_rtx (GET_MODE (decl_rtl));
4937 generating_concat_p = old_generating_concat_p;
4939 emit_move_insn (tmp, decl_rtl);
4940 emit_move_insn (real_decl_rtl, tmp);
4942 else
4943 emit_move_insn (real_decl_rtl, decl_rtl);
4947 /* If returning a structure, arrange to return the address of the value
4948 in a place where debuggers expect to find it.
4950 If returning a structure PCC style,
4951 the caller also depends on this value.
4952 And cfun->returns_pcc_struct is not necessarily set. */
4953 if (cfun->returns_struct
4954 || cfun->returns_pcc_struct)
4956 rtx value_address = DECL_RTL (DECL_RESULT (current_function_decl));
4957 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
4958 rtx outgoing;
4960 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))
4961 type = TREE_TYPE (type);
4962 else
4963 value_address = XEXP (value_address, 0);
4965 outgoing = targetm.calls.function_value (build_pointer_type (type),
4966 current_function_decl, true);
4968 /* Mark this as a function return value so integrate will delete the
4969 assignment and USE below when inlining this function. */
4970 REG_FUNCTION_VALUE_P (outgoing) = 1;
4972 /* The address may be ptr_mode and OUTGOING may be Pmode. */
4973 value_address = convert_memory_address (GET_MODE (outgoing),
4974 value_address);
4976 emit_move_insn (outgoing, value_address);
4978 /* Show return register used to hold result (in this case the address
4979 of the result. */
4980 crtl->return_rtx = outgoing;
4983 /* Emit the actual code to clobber return register. */
4985 rtx seq;
4987 start_sequence ();
4988 clobber_return_register ();
4989 seq = get_insns ();
4990 end_sequence ();
4992 emit_insn_after (seq, clobber_after);
4995 /* Output the label for the naked return from the function. */
4996 if (naked_return_label)
4997 emit_label (naked_return_label);
4999 /* @@@ This is a kludge. We want to ensure that instructions that
5000 may trap are not moved into the epilogue by scheduling, because
5001 we don't always emit unwind information for the epilogue. */
5002 if (!USING_SJLJ_EXCEPTIONS && cfun->can_throw_non_call_exceptions)
5003 emit_insn (gen_blockage ());
5005 /* If stack protection is enabled for this function, check the guard. */
5006 if (crtl->stack_protect_guard)
5007 stack_protect_epilogue ();
5009 /* If we had calls to alloca, and this machine needs
5010 an accurate stack pointer to exit the function,
5011 insert some code to save and restore the stack pointer. */
5012 if (! EXIT_IGNORE_STACK
5013 && cfun->calls_alloca)
5015 rtx tem = 0;
5017 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
5018 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
5021 /* ??? This should no longer be necessary since stupid is no longer with
5022 us, but there are some parts of the compiler (eg reload_combine, and
5023 sh mach_dep_reorg) that still try and compute their own lifetime info
5024 instead of using the general framework. */
5025 use_return_register ();
5029 get_arg_pointer_save_area (void)
5031 rtx ret = arg_pointer_save_area;
5033 if (! ret)
5035 ret = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
5036 arg_pointer_save_area = ret;
5039 if (! crtl->arg_pointer_save_area_init)
5041 rtx seq;
5043 /* Save the arg pointer at the beginning of the function. The
5044 generated stack slot may not be a valid memory address, so we
5045 have to check it and fix it if necessary. */
5046 start_sequence ();
5047 emit_move_insn (validize_mem (ret),
5048 crtl->args.internal_arg_pointer);
5049 seq = get_insns ();
5050 end_sequence ();
5052 push_topmost_sequence ();
5053 emit_insn_after (seq, entry_of_function ());
5054 pop_topmost_sequence ();
5057 return ret;
5060 /* Add a list of INSNS to the hash HASHP, possibly allocating HASHP
5061 for the first time. */
5063 static void
5064 record_insns (rtx insns, rtx end, htab_t *hashp)
5066 rtx tmp;
5067 htab_t hash = *hashp;
5069 if (hash == NULL)
5070 *hashp = hash
5071 = htab_create_ggc (17, htab_hash_pointer, htab_eq_pointer, NULL);
5073 for (tmp = insns; tmp != end; tmp = NEXT_INSN (tmp))
5075 void **slot = htab_find_slot (hash, tmp, INSERT);
5076 gcc_assert (*slot == NULL);
5077 *slot = tmp;
5081 /* INSN has been duplicated as COPY, as part of duping a basic block.
5082 If INSN is an epilogue insn, then record COPY as epilogue as well. */
5084 void
5085 maybe_copy_epilogue_insn (rtx insn, rtx copy)
5087 void **slot;
5089 if (epilogue_insn_hash == NULL
5090 || htab_find (epilogue_insn_hash, insn) == NULL)
5091 return;
5093 slot = htab_find_slot (epilogue_insn_hash, copy, INSERT);
5094 gcc_assert (*slot == NULL);
5095 *slot = copy;
5098 /* Set the locator of the insn chain starting at INSN to LOC. */
5099 static void
5100 set_insn_locators (rtx insn, int loc)
5102 while (insn != NULL_RTX)
5104 if (INSN_P (insn))
5105 INSN_LOCATOR (insn) = loc;
5106 insn = NEXT_INSN (insn);
5110 /* Determine if any INSNs in HASH are, or are part of, INSN. Because
5111 we can be running after reorg, SEQUENCE rtl is possible. */
5113 static bool
5114 contains (const_rtx insn, htab_t hash)
5116 if (hash == NULL)
5117 return false;
5119 if (NONJUMP_INSN_P (insn) && GET_CODE (PATTERN (insn)) == SEQUENCE)
5121 int i;
5122 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
5123 if (htab_find (hash, XVECEXP (PATTERN (insn), 0, i)))
5124 return true;
5125 return false;
5128 return htab_find (hash, insn) != NULL;
5132 prologue_epilogue_contains (const_rtx insn)
5134 if (contains (insn, prologue_insn_hash))
5135 return 1;
5136 if (contains (insn, epilogue_insn_hash))
5137 return 1;
5138 return 0;
5141 #ifdef HAVE_return
5142 /* Insert gen_return at the end of block BB. This also means updating
5143 block_for_insn appropriately. */
5145 static void
5146 emit_return_into_block (basic_block bb)
5148 emit_jump_insn_after (gen_return (), BB_END (bb));
5150 #endif /* HAVE_return */
5152 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
5153 this into place with notes indicating where the prologue ends and where
5154 the epilogue begins. Update the basic block information when possible. */
5156 static void
5157 thread_prologue_and_epilogue_insns (void)
5159 int inserted = 0;
5160 edge e;
5161 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
5162 rtx seq;
5163 #endif
5164 #if defined (HAVE_epilogue) || defined(HAVE_return)
5165 rtx epilogue_end = NULL_RTX;
5166 #endif
5167 edge_iterator ei;
5169 rtl_profile_for_bb (ENTRY_BLOCK_PTR);
5170 #ifdef HAVE_prologue
5171 if (HAVE_prologue)
5173 start_sequence ();
5174 seq = gen_prologue ();
5175 emit_insn (seq);
5177 /* Insert an explicit USE for the frame pointer
5178 if the profiling is on and the frame pointer is required. */
5179 if (crtl->profile && frame_pointer_needed)
5180 emit_use (hard_frame_pointer_rtx);
5182 /* Retain a map of the prologue insns. */
5183 record_insns (seq, NULL, &prologue_insn_hash);
5184 emit_note (NOTE_INSN_PROLOGUE_END);
5186 #ifndef PROFILE_BEFORE_PROLOGUE
5187 /* Ensure that instructions are not moved into the prologue when
5188 profiling is on. The call to the profiling routine can be
5189 emitted within the live range of a call-clobbered register. */
5190 if (crtl->profile)
5191 emit_insn (gen_blockage ());
5192 #endif
5194 seq = get_insns ();
5195 end_sequence ();
5196 set_insn_locators (seq, prologue_locator);
5198 /* Can't deal with multiple successors of the entry block
5199 at the moment. Function should always have at least one
5200 entry point. */
5201 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR));
5203 insert_insn_on_edge (seq, single_succ_edge (ENTRY_BLOCK_PTR));
5204 inserted = 1;
5206 #endif
5208 /* If the exit block has no non-fake predecessors, we don't need
5209 an epilogue. */
5210 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5211 if ((e->flags & EDGE_FAKE) == 0)
5212 break;
5213 if (e == NULL)
5214 goto epilogue_done;
5216 rtl_profile_for_bb (EXIT_BLOCK_PTR);
5217 #ifdef HAVE_return
5218 if (optimize && HAVE_return)
5220 /* If we're allowed to generate a simple return instruction,
5221 then by definition we don't need a full epilogue. Examine
5222 the block that falls through to EXIT. If it does not
5223 contain any code, examine its predecessors and try to
5224 emit (conditional) return instructions. */
5226 basic_block last;
5227 rtx label;
5229 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5230 if (e->flags & EDGE_FALLTHRU)
5231 break;
5232 if (e == NULL)
5233 goto epilogue_done;
5234 last = e->src;
5236 /* Verify that there are no active instructions in the last block. */
5237 label = BB_END (last);
5238 while (label && !LABEL_P (label))
5240 if (active_insn_p (label))
5241 break;
5242 label = PREV_INSN (label);
5245 if (BB_HEAD (last) == label && LABEL_P (label))
5247 edge_iterator ei2;
5249 for (ei2 = ei_start (last->preds); (e = ei_safe_edge (ei2)); )
5251 basic_block bb = e->src;
5252 rtx jump;
5254 if (bb == ENTRY_BLOCK_PTR)
5256 ei_next (&ei2);
5257 continue;
5260 jump = BB_END (bb);
5261 if (!JUMP_P (jump) || JUMP_LABEL (jump) != label)
5263 ei_next (&ei2);
5264 continue;
5267 /* If we have an unconditional jump, we can replace that
5268 with a simple return instruction. */
5269 if (simplejump_p (jump))
5271 emit_return_into_block (bb);
5272 delete_insn (jump);
5275 /* If we have a conditional jump, we can try to replace
5276 that with a conditional return instruction. */
5277 else if (condjump_p (jump))
5279 if (! redirect_jump (jump, 0, 0))
5281 ei_next (&ei2);
5282 continue;
5285 /* If this block has only one successor, it both jumps
5286 and falls through to the fallthru block, so we can't
5287 delete the edge. */
5288 if (single_succ_p (bb))
5290 ei_next (&ei2);
5291 continue;
5294 else
5296 ei_next (&ei2);
5297 continue;
5300 /* Fix up the CFG for the successful change we just made. */
5301 redirect_edge_succ (e, EXIT_BLOCK_PTR);
5304 /* Emit a return insn for the exit fallthru block. Whether
5305 this is still reachable will be determined later. */
5307 emit_barrier_after (BB_END (last));
5308 emit_return_into_block (last);
5309 epilogue_end = BB_END (last);
5310 single_succ_edge (last)->flags &= ~EDGE_FALLTHRU;
5311 goto epilogue_done;
5314 #endif
5316 /* A small fib -- epilogue is not yet completed, but we wish to re-use
5317 this marker for the splits of EH_RETURN patterns, and nothing else
5318 uses the flag in the meantime. */
5319 epilogue_completed = 1;
5321 #ifdef HAVE_eh_return
5322 /* Find non-fallthru edges that end with EH_RETURN instructions. On
5323 some targets, these get split to a special version of the epilogue
5324 code. In order to be able to properly annotate these with unwind
5325 info, try to split them now. If we get a valid split, drop an
5326 EPILOGUE_BEG note and mark the insns as epilogue insns. */
5327 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5329 rtx prev, last, trial;
5331 if (e->flags & EDGE_FALLTHRU)
5332 continue;
5333 last = BB_END (e->src);
5334 if (!eh_returnjump_p (last))
5335 continue;
5337 prev = PREV_INSN (last);
5338 trial = try_split (PATTERN (last), last, 1);
5339 if (trial == last)
5340 continue;
5342 record_insns (NEXT_INSN (prev), NEXT_INSN (trial), &epilogue_insn_hash);
5343 emit_note_after (NOTE_INSN_EPILOGUE_BEG, prev);
5345 #endif
5347 /* Find the edge that falls through to EXIT. Other edges may exist
5348 due to RETURN instructions, but those don't need epilogues.
5349 There really shouldn't be a mixture -- either all should have
5350 been converted or none, however... */
5352 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5353 if (e->flags & EDGE_FALLTHRU)
5354 break;
5355 if (e == NULL)
5356 goto epilogue_done;
5358 #ifdef HAVE_epilogue
5359 if (HAVE_epilogue)
5361 start_sequence ();
5362 epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG);
5363 seq = gen_epilogue ();
5364 emit_jump_insn (seq);
5366 /* Retain a map of the epilogue insns. */
5367 record_insns (seq, NULL, &epilogue_insn_hash);
5368 set_insn_locators (seq, epilogue_locator);
5370 seq = get_insns ();
5371 end_sequence ();
5373 insert_insn_on_edge (seq, e);
5374 inserted = 1;
5376 else
5377 #endif
5379 basic_block cur_bb;
5381 if (! next_active_insn (BB_END (e->src)))
5382 goto epilogue_done;
5383 /* We have a fall-through edge to the exit block, the source is not
5384 at the end of the function, and there will be an assembler epilogue
5385 at the end of the function.
5386 We can't use force_nonfallthru here, because that would try to
5387 use return. Inserting a jump 'by hand' is extremely messy, so
5388 we take advantage of cfg_layout_finalize using
5389 fixup_fallthru_exit_predecessor. */
5390 cfg_layout_initialize (0);
5391 FOR_EACH_BB (cur_bb)
5392 if (cur_bb->index >= NUM_FIXED_BLOCKS
5393 && cur_bb->next_bb->index >= NUM_FIXED_BLOCKS)
5394 cur_bb->aux = cur_bb->next_bb;
5395 cfg_layout_finalize ();
5397 epilogue_done:
5398 default_rtl_profile ();
5400 if (inserted)
5402 commit_edge_insertions ();
5404 /* The epilogue insns we inserted may cause the exit edge to no longer
5405 be fallthru. */
5406 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5408 if (((e->flags & EDGE_FALLTHRU) != 0)
5409 && returnjump_p (BB_END (e->src)))
5410 e->flags &= ~EDGE_FALLTHRU;
5414 #ifdef HAVE_sibcall_epilogue
5415 /* Emit sibling epilogues before any sibling call sites. */
5416 for (ei = ei_start (EXIT_BLOCK_PTR->preds); (e = ei_safe_edge (ei)); )
5418 basic_block bb = e->src;
5419 rtx insn = BB_END (bb);
5421 if (!CALL_P (insn)
5422 || ! SIBLING_CALL_P (insn))
5424 ei_next (&ei);
5425 continue;
5428 start_sequence ();
5429 emit_note (NOTE_INSN_EPILOGUE_BEG);
5430 emit_insn (gen_sibcall_epilogue ());
5431 seq = get_insns ();
5432 end_sequence ();
5434 /* Retain a map of the epilogue insns. Used in life analysis to
5435 avoid getting rid of sibcall epilogue insns. Do this before we
5436 actually emit the sequence. */
5437 record_insns (seq, NULL, &epilogue_insn_hash);
5438 set_insn_locators (seq, epilogue_locator);
5440 emit_insn_before (seq, insn);
5441 ei_next (&ei);
5443 #endif
5445 #ifdef HAVE_epilogue
5446 if (epilogue_end)
5448 rtx insn, next;
5450 /* Similarly, move any line notes that appear after the epilogue.
5451 There is no need, however, to be quite so anal about the existence
5452 of such a note. Also possibly move
5453 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
5454 info generation. */
5455 for (insn = epilogue_end; insn; insn = next)
5457 next = NEXT_INSN (insn);
5458 if (NOTE_P (insn)
5459 && (NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG))
5460 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
5463 #endif
5465 /* Threading the prologue and epilogue changes the artificial refs
5466 in the entry and exit blocks. */
5467 epilogue_completed = 1;
5468 df_update_entry_exit_and_calls ();
5471 /* Reposition the prologue-end and epilogue-begin notes after
5472 instruction scheduling. */
5474 void
5475 reposition_prologue_and_epilogue_notes (void)
5477 #if defined (HAVE_prologue) || defined (HAVE_epilogue) \
5478 || defined (HAVE_sibcall_epilogue)
5479 /* Since the hash table is created on demand, the fact that it is
5480 non-null is a signal that it is non-empty. */
5481 if (prologue_insn_hash != NULL)
5483 size_t len = htab_elements (prologue_insn_hash);
5484 rtx insn, last = NULL, note = NULL;
5486 /* Scan from the beginning until we reach the last prologue insn. */
5487 /* ??? While we do have the CFG intact, there are two problems:
5488 (1) The prologue can contain loops (typically probing the stack),
5489 which means that the end of the prologue isn't in the first bb.
5490 (2) Sometimes the PROLOGUE_END note gets pushed into the next bb. */
5491 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
5493 if (NOTE_P (insn))
5495 if (NOTE_KIND (insn) == NOTE_INSN_PROLOGUE_END)
5496 note = insn;
5498 else if (contains (insn, prologue_insn_hash))
5500 last = insn;
5501 if (--len == 0)
5502 break;
5506 if (last)
5508 if (note == NULL)
5510 /* Scan forward looking for the PROLOGUE_END note. It should
5511 be right at the beginning of the block, possibly with other
5512 insn notes that got moved there. */
5513 for (note = NEXT_INSN (last); ; note = NEXT_INSN (note))
5515 if (NOTE_P (note)
5516 && NOTE_KIND (note) == NOTE_INSN_PROLOGUE_END)
5517 break;
5521 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
5522 if (LABEL_P (last))
5523 last = NEXT_INSN (last);
5524 reorder_insns (note, note, last);
5528 if (epilogue_insn_hash != NULL)
5530 edge_iterator ei;
5531 edge e;
5533 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5535 rtx insn, first = NULL, note = NULL;
5536 basic_block bb = e->src;
5538 /* Scan from the beginning until we reach the first epilogue insn. */
5539 FOR_BB_INSNS (bb, insn)
5541 if (NOTE_P (insn))
5543 if (NOTE_KIND (insn) == NOTE_INSN_EPILOGUE_BEG)
5545 note = insn;
5546 if (first != NULL)
5547 break;
5550 else if (first == NULL && contains (insn, epilogue_insn_hash))
5552 first = insn;
5553 if (note != NULL)
5554 break;
5558 if (note)
5560 /* If the function has a single basic block, and no real
5561 epilogue insns (e.g. sibcall with no cleanup), the
5562 epilogue note can get scheduled before the prologue
5563 note. If we have frame related prologue insns, having
5564 them scanned during the epilogue will result in a crash.
5565 In this case re-order the epilogue note to just before
5566 the last insn in the block. */
5567 if (first == NULL)
5568 first = BB_END (bb);
5570 if (PREV_INSN (first) != note)
5571 reorder_insns (note, note, PREV_INSN (first));
5575 #endif /* HAVE_prologue or HAVE_epilogue */
5578 /* Returns the name of the current function. */
5579 const char *
5580 current_function_name (void)
5582 if (cfun == NULL)
5583 return "<none>";
5584 return lang_hooks.decl_printable_name (cfun->decl, 2);
5588 static unsigned int
5589 rest_of_handle_check_leaf_regs (void)
5591 #ifdef LEAF_REGISTERS
5592 current_function_uses_only_leaf_regs
5593 = optimize > 0 && only_leaf_regs_used () && leaf_function_p ();
5594 #endif
5595 return 0;
5598 /* Insert a TYPE into the used types hash table of CFUN. */
5600 static void
5601 used_types_insert_helper (tree type, struct function *func)
5603 if (type != NULL && func != NULL)
5605 void **slot;
5607 if (func->used_types_hash == NULL)
5608 func->used_types_hash = htab_create_ggc (37, htab_hash_pointer,
5609 htab_eq_pointer, NULL);
5610 slot = htab_find_slot (func->used_types_hash, type, INSERT);
5611 if (*slot == NULL)
5612 *slot = type;
5616 /* Given a type, insert it into the used hash table in cfun. */
5617 void
5618 used_types_insert (tree t)
5620 while (POINTER_TYPE_P (t) || TREE_CODE (t) == ARRAY_TYPE)
5621 if (TYPE_NAME (t))
5622 break;
5623 else
5624 t = TREE_TYPE (t);
5625 if (TYPE_NAME (t) == NULL_TREE
5626 || TYPE_NAME (t) == TYPE_NAME (TYPE_MAIN_VARIANT (t)))
5627 t = TYPE_MAIN_VARIANT (t);
5628 if (debug_info_level > DINFO_LEVEL_NONE)
5630 if (cfun)
5631 used_types_insert_helper (t, cfun);
5632 else
5633 /* So this might be a type referenced by a global variable.
5634 Record that type so that we can later decide to emit its debug
5635 information. */
5636 VEC_safe_push (tree, gc, types_used_by_cur_var_decl, t);
5640 /* Helper to Hash a struct types_used_by_vars_entry. */
5642 static hashval_t
5643 hash_types_used_by_vars_entry (const struct types_used_by_vars_entry *entry)
5645 gcc_assert (entry && entry->var_decl && entry->type);
5647 return iterative_hash_object (entry->type,
5648 iterative_hash_object (entry->var_decl, 0));
5651 /* Hash function of the types_used_by_vars_entry hash table. */
5653 hashval_t
5654 types_used_by_vars_do_hash (const void *x)
5656 const struct types_used_by_vars_entry *entry =
5657 (const struct types_used_by_vars_entry *) x;
5659 return hash_types_used_by_vars_entry (entry);
5662 /*Equality function of the types_used_by_vars_entry hash table. */
5665 types_used_by_vars_eq (const void *x1, const void *x2)
5667 const struct types_used_by_vars_entry *e1 =
5668 (const struct types_used_by_vars_entry *) x1;
5669 const struct types_used_by_vars_entry *e2 =
5670 (const struct types_used_by_vars_entry *)x2;
5672 return (e1->var_decl == e2->var_decl && e1->type == e2->type);
5675 /* Inserts an entry into the types_used_by_vars_hash hash table. */
5677 void
5678 types_used_by_var_decl_insert (tree type, tree var_decl)
5680 if (type != NULL && var_decl != NULL)
5682 void **slot;
5683 struct types_used_by_vars_entry e;
5684 e.var_decl = var_decl;
5685 e.type = type;
5686 if (types_used_by_vars_hash == NULL)
5687 types_used_by_vars_hash =
5688 htab_create_ggc (37, types_used_by_vars_do_hash,
5689 types_used_by_vars_eq, NULL);
5690 slot = htab_find_slot_with_hash (types_used_by_vars_hash, &e,
5691 hash_types_used_by_vars_entry (&e), INSERT);
5692 if (*slot == NULL)
5694 struct types_used_by_vars_entry *entry;
5695 entry = ggc_alloc_types_used_by_vars_entry ();
5696 entry->type = type;
5697 entry->var_decl = var_decl;
5698 *slot = entry;
5703 struct rtl_opt_pass pass_leaf_regs =
5706 RTL_PASS,
5707 "*leaf_regs", /* name */
5708 NULL, /* gate */
5709 rest_of_handle_check_leaf_regs, /* execute */
5710 NULL, /* sub */
5711 NULL, /* next */
5712 0, /* static_pass_number */
5713 TV_NONE, /* tv_id */
5714 0, /* properties_required */
5715 0, /* properties_provided */
5716 0, /* properties_destroyed */
5717 0, /* todo_flags_start */
5718 0 /* todo_flags_finish */
5722 static unsigned int
5723 rest_of_handle_thread_prologue_and_epilogue (void)
5725 if (optimize)
5726 cleanup_cfg (CLEANUP_EXPENSIVE);
5727 /* On some machines, the prologue and epilogue code, or parts thereof,
5728 can be represented as RTL. Doing so lets us schedule insns between
5729 it and the rest of the code and also allows delayed branch
5730 scheduling to operate in the epilogue. */
5732 thread_prologue_and_epilogue_insns ();
5733 return 0;
5736 struct rtl_opt_pass pass_thread_prologue_and_epilogue =
5739 RTL_PASS,
5740 "pro_and_epilogue", /* name */
5741 NULL, /* gate */
5742 rest_of_handle_thread_prologue_and_epilogue, /* execute */
5743 NULL, /* sub */
5744 NULL, /* next */
5745 0, /* static_pass_number */
5746 TV_THREAD_PROLOGUE_AND_EPILOGUE, /* tv_id */
5747 0, /* properties_required */
5748 0, /* properties_provided */
5749 0, /* properties_destroyed */
5750 TODO_verify_flow, /* todo_flags_start */
5751 TODO_dump_func |
5752 TODO_df_verify |
5753 TODO_df_finish | TODO_verify_rtl_sharing |
5754 TODO_ggc_collect /* todo_flags_finish */
5759 /* This mini-pass fixes fall-out from SSA in asm statements that have
5760 in-out constraints. Say you start with
5762 orig = inout;
5763 asm ("": "+mr" (inout));
5764 use (orig);
5766 which is transformed very early to use explicit output and match operands:
5768 orig = inout;
5769 asm ("": "=mr" (inout) : "0" (inout));
5770 use (orig);
5772 Or, after SSA and copyprop,
5774 asm ("": "=mr" (inout_2) : "0" (inout_1));
5775 use (inout_1);
5777 Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
5778 they represent two separate values, so they will get different pseudo
5779 registers during expansion. Then, since the two operands need to match
5780 per the constraints, but use different pseudo registers, reload can
5781 only register a reload for these operands. But reloads can only be
5782 satisfied by hardregs, not by memory, so we need a register for this
5783 reload, just because we are presented with non-matching operands.
5784 So, even though we allow memory for this operand, no memory can be
5785 used for it, just because the two operands don't match. This can
5786 cause reload failures on register-starved targets.
5788 So it's a symptom of reload not being able to use memory for reloads
5789 or, alternatively it's also a symptom of both operands not coming into
5790 reload as matching (in which case the pseudo could go to memory just
5791 fine, as the alternative allows it, and no reload would be necessary).
5792 We fix the latter problem here, by transforming
5794 asm ("": "=mr" (inout_2) : "0" (inout_1));
5796 back to
5798 inout_2 = inout_1;
5799 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
5801 static void
5802 match_asm_constraints_1 (rtx insn, rtx *p_sets, int noutputs)
5804 int i;
5805 bool changed = false;
5806 rtx op = SET_SRC (p_sets[0]);
5807 int ninputs = ASM_OPERANDS_INPUT_LENGTH (op);
5808 rtvec inputs = ASM_OPERANDS_INPUT_VEC (op);
5809 bool *output_matched = XALLOCAVEC (bool, noutputs);
5811 memset (output_matched, 0, noutputs * sizeof (bool));
5812 for (i = 0; i < ninputs; i++)
5814 rtx input, output, insns;
5815 const char *constraint = ASM_OPERANDS_INPUT_CONSTRAINT (op, i);
5816 char *end;
5817 int match, j;
5819 if (*constraint == '%')
5820 constraint++;
5822 match = strtoul (constraint, &end, 10);
5823 if (end == constraint)
5824 continue;
5826 gcc_assert (match < noutputs);
5827 output = SET_DEST (p_sets[match]);
5828 input = RTVEC_ELT (inputs, i);
5829 /* Only do the transformation for pseudos. */
5830 if (! REG_P (output)
5831 || rtx_equal_p (output, input)
5832 || (GET_MODE (input) != VOIDmode
5833 && GET_MODE (input) != GET_MODE (output)))
5834 continue;
5836 /* We can't do anything if the output is also used as input,
5837 as we're going to overwrite it. */
5838 for (j = 0; j < ninputs; j++)
5839 if (reg_overlap_mentioned_p (output, RTVEC_ELT (inputs, j)))
5840 break;
5841 if (j != ninputs)
5842 continue;
5844 /* Avoid changing the same input several times. For
5845 asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
5846 only change in once (to out1), rather than changing it
5847 first to out1 and afterwards to out2. */
5848 if (i > 0)
5850 for (j = 0; j < noutputs; j++)
5851 if (output_matched[j] && input == SET_DEST (p_sets[j]))
5852 break;
5853 if (j != noutputs)
5854 continue;
5856 output_matched[match] = true;
5858 start_sequence ();
5859 emit_move_insn (output, input);
5860 insns = get_insns ();
5861 end_sequence ();
5862 emit_insn_before (insns, insn);
5864 /* Now replace all mentions of the input with output. We can't
5865 just replace the occurrence in inputs[i], as the register might
5866 also be used in some other input (or even in an address of an
5867 output), which would mean possibly increasing the number of
5868 inputs by one (namely 'output' in addition), which might pose
5869 a too complicated problem for reload to solve. E.g. this situation:
5871 asm ("" : "=r" (output), "=m" (input) : "0" (input))
5873 Here 'input' is used in two occurrences as input (once for the
5874 input operand, once for the address in the second output operand).
5875 If we would replace only the occurrence of the input operand (to
5876 make the matching) we would be left with this:
5878 output = input
5879 asm ("" : "=r" (output), "=m" (input) : "0" (output))
5881 Now we suddenly have two different input values (containing the same
5882 value, but different pseudos) where we formerly had only one.
5883 With more complicated asms this might lead to reload failures
5884 which wouldn't have happen without this pass. So, iterate over
5885 all operands and replace all occurrences of the register used. */
5886 for (j = 0; j < noutputs; j++)
5887 if (!rtx_equal_p (SET_DEST (p_sets[j]), input)
5888 && reg_overlap_mentioned_p (input, SET_DEST (p_sets[j])))
5889 SET_DEST (p_sets[j]) = replace_rtx (SET_DEST (p_sets[j]),
5890 input, output);
5891 for (j = 0; j < ninputs; j++)
5892 if (reg_overlap_mentioned_p (input, RTVEC_ELT (inputs, j)))
5893 RTVEC_ELT (inputs, j) = replace_rtx (RTVEC_ELT (inputs, j),
5894 input, output);
5896 changed = true;
5899 if (changed)
5900 df_insn_rescan (insn);
5903 static unsigned
5904 rest_of_match_asm_constraints (void)
5906 basic_block bb;
5907 rtx insn, pat, *p_sets;
5908 int noutputs;
5910 if (!crtl->has_asm_statement)
5911 return 0;
5913 df_set_flags (DF_DEFER_INSN_RESCAN);
5914 FOR_EACH_BB (bb)
5916 FOR_BB_INSNS (bb, insn)
5918 if (!INSN_P (insn))
5919 continue;
5921 pat = PATTERN (insn);
5922 if (GET_CODE (pat) == PARALLEL)
5923 p_sets = &XVECEXP (pat, 0, 0), noutputs = XVECLEN (pat, 0);
5924 else if (GET_CODE (pat) == SET)
5925 p_sets = &PATTERN (insn), noutputs = 1;
5926 else
5927 continue;
5929 if (GET_CODE (*p_sets) == SET
5930 && GET_CODE (SET_SRC (*p_sets)) == ASM_OPERANDS)
5931 match_asm_constraints_1 (insn, p_sets, noutputs);
5935 return TODO_df_finish;
5938 struct rtl_opt_pass pass_match_asm_constraints =
5941 RTL_PASS,
5942 "asmcons", /* name */
5943 NULL, /* gate */
5944 rest_of_match_asm_constraints, /* execute */
5945 NULL, /* sub */
5946 NULL, /* next */
5947 0, /* static_pass_number */
5948 TV_NONE, /* tv_id */
5949 0, /* properties_required */
5950 0, /* properties_provided */
5951 0, /* properties_destroyed */
5952 0, /* todo_flags_start */
5953 TODO_dump_func /* todo_flags_finish */
5958 #include "gt-function.h"