* opt-functions.awk (var_type): New function.
[official-gcc.git] / gcc / function.c
blob2e2152da49801767912bc1841c2a8cff7c5ac531
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
4 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 2, 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 COPYING. If not, write to the Free
20 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
21 02111-1307, USA. */
23 /* This file handles the generation of rtl code from tree structure
24 at the level of the function as a whole.
25 It creates the rtl expressions for parameters and auto variables
26 and has full responsibility for allocating stack slots.
28 `expand_function_start' is called at the beginning of a function,
29 before the function body is parsed, and `expand_function_end' is
30 called after parsing the body.
32 Call `assign_stack_local' to allocate a stack slot for a local variable.
33 This is usually done during the RTL generation for the function body,
34 but it can also be done in the reload pass when a pseudo-register does
35 not get a hard register. */
37 #include "config.h"
38 #include "system.h"
39 #include "coretypes.h"
40 #include "tm.h"
41 #include "rtl.h"
42 #include "tree.h"
43 #include "flags.h"
44 #include "except.h"
45 #include "function.h"
46 #include "expr.h"
47 #include "optabs.h"
48 #include "libfuncs.h"
49 #include "regs.h"
50 #include "hard-reg-set.h"
51 #include "insn-config.h"
52 #include "recog.h"
53 #include "output.h"
54 #include "basic-block.h"
55 #include "toplev.h"
56 #include "hashtab.h"
57 #include "ggc.h"
58 #include "tm_p.h"
59 #include "integrate.h"
60 #include "langhooks.h"
61 #include "target.h"
62 #include "cfglayout.h"
63 #include "tree-gimple.h"
65 #ifndef LOCAL_ALIGNMENT
66 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
67 #endif
69 #ifndef STACK_ALIGNMENT_NEEDED
70 #define STACK_ALIGNMENT_NEEDED 1
71 #endif
73 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
75 /* Some systems use __main in a way incompatible with its use in gcc, in these
76 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
77 give the same symbol without quotes for an alternative entry point. You
78 must define both, or neither. */
79 #ifndef NAME__MAIN
80 #define NAME__MAIN "__main"
81 #endif
83 /* Round a value to the lowest integer less than it that is a multiple of
84 the required alignment. Avoid using division in case the value is
85 negative. Assume the alignment is a power of two. */
86 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
88 /* Similar, but round to the next highest integer that meets the
89 alignment. */
90 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
92 /* Nonzero if function being compiled doesn't contain any calls
93 (ignoring the prologue and epilogue). This is set prior to
94 local register allocation and is valid for the remaining
95 compiler passes. */
96 int current_function_is_leaf;
98 /* Nonzero if function being compiled doesn't modify the stack pointer
99 (ignoring the prologue and epilogue). This is only valid after
100 life_analysis has run. */
101 int current_function_sp_is_unchanging;
103 /* Nonzero if the function being compiled is a leaf function which only
104 uses leaf registers. This is valid after reload (specifically after
105 sched2) and is useful only if the port defines LEAF_REGISTERS. */
106 int current_function_uses_only_leaf_regs;
108 /* Nonzero once virtual register instantiation has been done.
109 assign_stack_local uses frame_pointer_rtx when this is nonzero.
110 calls.c:emit_library_call_value_1 uses it to set up
111 post-instantiation libcalls. */
112 int virtuals_instantiated;
114 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
115 static GTY(()) int funcdef_no;
117 /* These variables hold pointers to functions to create and destroy
118 target specific, per-function data structures. */
119 struct machine_function * (*init_machine_status) (void);
121 /* The currently compiled function. */
122 struct function *cfun = 0;
124 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
125 static GTY(()) varray_type prologue;
126 static GTY(()) varray_type epilogue;
128 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
129 in this function. */
130 static GTY(()) varray_type sibcall_epilogue;
132 /* In order to evaluate some expressions, such as function calls returning
133 structures in memory, we need to temporarily allocate stack locations.
134 We record each allocated temporary in the following structure.
136 Associated with each temporary slot is a nesting level. When we pop up
137 one level, all temporaries associated with the previous level are freed.
138 Normally, all temporaries are freed after the execution of the statement
139 in which they were created. However, if we are inside a ({...}) grouping,
140 the result may be in a temporary and hence must be preserved. If the
141 result could be in a temporary, we preserve it if we can determine which
142 one it is in. If we cannot determine which temporary may contain the
143 result, all temporaries are preserved. A temporary is preserved by
144 pretending it was allocated at the previous nesting level.
146 Automatic variables are also assigned temporary slots, at the nesting
147 level where they are defined. They are marked a "kept" so that
148 free_temp_slots will not free them. */
150 struct temp_slot GTY(())
152 /* Points to next temporary slot. */
153 struct temp_slot *next;
154 /* Points to previous temporary slot. */
155 struct temp_slot *prev;
157 /* The rtx to used to reference the slot. */
158 rtx slot;
159 /* The rtx used to represent the address if not the address of the
160 slot above. May be an EXPR_LIST if multiple addresses exist. */
161 rtx address;
162 /* The alignment (in bits) of the slot. */
163 unsigned int align;
164 /* The size, in units, of the slot. */
165 HOST_WIDE_INT size;
166 /* The type of the object in the slot, or zero if it doesn't correspond
167 to a type. We use this to determine whether a slot can be reused.
168 It can be reused if objects of the type of the new slot will always
169 conflict with objects of the type of the old slot. */
170 tree type;
171 /* Nonzero if this temporary is currently in use. */
172 char in_use;
173 /* Nonzero if this temporary has its address taken. */
174 char addr_taken;
175 /* Nesting level at which this slot is being used. */
176 int level;
177 /* Nonzero if this should survive a call to free_temp_slots. */
178 int keep;
179 /* The offset of the slot from the frame_pointer, including extra space
180 for alignment. This info is for combine_temp_slots. */
181 HOST_WIDE_INT base_offset;
182 /* The size of the slot, including extra space for alignment. This
183 info is for combine_temp_slots. */
184 HOST_WIDE_INT full_size;
187 /* Forward declarations. */
189 static rtx assign_stack_local_1 (enum machine_mode, HOST_WIDE_INT, int,
190 struct function *);
191 static struct temp_slot *find_temp_slot_from_address (rtx);
192 static void pad_to_arg_alignment (struct args_size *, int, struct args_size *);
193 static void pad_below (struct args_size *, enum machine_mode, tree);
194 static void reorder_blocks_1 (rtx, tree, VEC(tree,heap) **);
195 static void reorder_fix_fragments (tree);
196 static int all_blocks (tree, tree *);
197 static tree *get_block_vector (tree, int *);
198 extern tree debug_find_var_in_block_tree (tree, tree);
199 /* We always define `record_insns' even if it's not used so that we
200 can always export `prologue_epilogue_contains'. */
201 static void record_insns (rtx, varray_type *) ATTRIBUTE_UNUSED;
202 static int contains (rtx, varray_type);
203 #ifdef HAVE_return
204 static void emit_return_into_block (basic_block, rtx);
205 #endif
206 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
207 static rtx keep_stack_depressed (rtx);
208 #endif
209 static void prepare_function_start (tree);
210 static void do_clobber_return_reg (rtx, void *);
211 static void do_use_return_reg (rtx, void *);
212 static void set_insn_locators (rtx, int) ATTRIBUTE_UNUSED;
214 /* Pointer to chain of `struct function' for containing functions. */
215 struct function *outer_function_chain;
217 /* Given a function decl for a containing function,
218 return the `struct function' for it. */
220 struct function *
221 find_function_data (tree decl)
223 struct function *p;
225 for (p = outer_function_chain; p; p = p->outer)
226 if (p->decl == decl)
227 return p;
229 gcc_unreachable ();
232 /* Save the current context for compilation of a nested function.
233 This is called from language-specific code. The caller should use
234 the enter_nested langhook to save any language-specific state,
235 since this function knows only about language-independent
236 variables. */
238 void
239 push_function_context_to (tree context ATTRIBUTE_UNUSED)
241 struct function *p;
243 if (cfun == 0)
244 init_dummy_function_start ();
245 p = cfun;
247 p->outer = outer_function_chain;
248 outer_function_chain = p;
250 lang_hooks.function.enter_nested (p);
252 cfun = 0;
255 void
256 push_function_context (void)
258 push_function_context_to (current_function_decl);
261 /* Restore the last saved context, at the end of a nested function.
262 This function is called from language-specific code. */
264 void
265 pop_function_context_from (tree context ATTRIBUTE_UNUSED)
267 struct function *p = outer_function_chain;
269 cfun = p;
270 outer_function_chain = p->outer;
272 current_function_decl = p->decl;
274 lang_hooks.function.leave_nested (p);
276 /* Reset variables that have known state during rtx generation. */
277 virtuals_instantiated = 0;
278 generating_concat_p = 1;
281 void
282 pop_function_context (void)
284 pop_function_context_from (current_function_decl);
287 /* Clear out all parts of the state in F that can safely be discarded
288 after the function has been parsed, but not compiled, to let
289 garbage collection reclaim the memory. */
291 void
292 free_after_parsing (struct function *f)
294 /* f->expr->forced_labels is used by code generation. */
295 /* f->emit->regno_reg_rtx is used by code generation. */
296 /* f->varasm is used by code generation. */
297 /* f->eh->eh_return_stub_label is used by code generation. */
299 lang_hooks.function.final (f);
302 /* Clear out all parts of the state in F that can safely be discarded
303 after the function has been compiled, to let garbage collection
304 reclaim the memory. */
306 void
307 free_after_compilation (struct function *f)
309 f->eh = NULL;
310 f->expr = NULL;
311 f->emit = NULL;
312 f->varasm = NULL;
313 f->machine = NULL;
314 f->cfg = NULL;
316 f->x_avail_temp_slots = NULL;
317 f->x_used_temp_slots = NULL;
318 f->arg_offset_rtx = NULL;
319 f->return_rtx = NULL;
320 f->internal_arg_pointer = NULL;
321 f->x_nonlocal_goto_handler_labels = NULL;
322 f->x_return_label = NULL;
323 f->x_naked_return_label = NULL;
324 f->x_stack_slot_list = NULL;
325 f->x_tail_recursion_reentry = NULL;
326 f->x_arg_pointer_save_area = NULL;
327 f->x_parm_birth_insn = NULL;
328 f->original_arg_vector = NULL;
329 f->original_decl_initial = NULL;
330 f->epilogue_delay_list = NULL;
333 /* Allocate fixed slots in the stack frame of the current function. */
335 /* Return size needed for stack frame based on slots so far allocated in
336 function F.
337 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
338 the caller may have to do that. */
340 static HOST_WIDE_INT
341 get_func_frame_size (struct function *f)
343 #ifdef FRAME_GROWS_DOWNWARD
344 return -f->x_frame_offset;
345 #else
346 return f->x_frame_offset;
347 #endif
350 /* Return size needed for stack frame based on slots so far allocated.
351 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
352 the caller may have to do that. */
353 HOST_WIDE_INT
354 get_frame_size (void)
356 return get_func_frame_size (cfun);
359 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
360 with machine mode MODE.
362 ALIGN controls the amount of alignment for the address of the slot:
363 0 means according to MODE,
364 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
365 -2 means use BITS_PER_UNIT,
366 positive specifies alignment boundary in bits.
368 We do not round to stack_boundary here.
370 FUNCTION specifies the function to allocate in. */
372 static rtx
373 assign_stack_local_1 (enum machine_mode mode, HOST_WIDE_INT size, int align,
374 struct function *function)
376 rtx x, addr;
377 int bigend_correction = 0;
378 unsigned int alignment;
379 int frame_off, frame_alignment, frame_phase;
381 if (align == 0)
383 tree type;
385 if (mode == BLKmode)
386 alignment = BIGGEST_ALIGNMENT;
387 else
388 alignment = GET_MODE_ALIGNMENT (mode);
390 /* Allow the target to (possibly) increase the alignment of this
391 stack slot. */
392 type = lang_hooks.types.type_for_mode (mode, 0);
393 if (type)
394 alignment = LOCAL_ALIGNMENT (type, alignment);
396 alignment /= BITS_PER_UNIT;
398 else if (align == -1)
400 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
401 size = CEIL_ROUND (size, alignment);
403 else if (align == -2)
404 alignment = 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
405 else
406 alignment = align / BITS_PER_UNIT;
408 #ifdef FRAME_GROWS_DOWNWARD
409 function->x_frame_offset -= size;
410 #endif
412 /* Ignore alignment we can't do with expected alignment of the boundary. */
413 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
414 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
416 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
417 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
419 /* Calculate how many bytes the start of local variables is off from
420 stack alignment. */
421 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
422 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
423 frame_phase = frame_off ? frame_alignment - frame_off : 0;
425 /* Round the frame offset to the specified alignment. The default is
426 to always honor requests to align the stack but a port may choose to
427 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
428 if (STACK_ALIGNMENT_NEEDED
429 || mode != BLKmode
430 || size != 0)
432 /* We must be careful here, since FRAME_OFFSET might be negative and
433 division with a negative dividend isn't as well defined as we might
434 like. So we instead assume that ALIGNMENT is a power of two and
435 use logical operations which are unambiguous. */
436 #ifdef FRAME_GROWS_DOWNWARD
437 function->x_frame_offset
438 = (FLOOR_ROUND (function->x_frame_offset - frame_phase,
439 (unsigned HOST_WIDE_INT) alignment)
440 + frame_phase);
441 #else
442 function->x_frame_offset
443 = (CEIL_ROUND (function->x_frame_offset - frame_phase,
444 (unsigned HOST_WIDE_INT) alignment)
445 + frame_phase);
446 #endif
449 /* On a big-endian machine, if we are allocating more space than we will use,
450 use the least significant bytes of those that are allocated. */
451 if (BYTES_BIG_ENDIAN && mode != BLKmode)
452 bigend_correction = size - GET_MODE_SIZE (mode);
454 /* If we have already instantiated virtual registers, return the actual
455 address relative to the frame pointer. */
456 if (function == cfun && virtuals_instantiated)
457 addr = plus_constant (frame_pointer_rtx,
458 trunc_int_for_mode
459 (frame_offset + bigend_correction
460 + STARTING_FRAME_OFFSET, Pmode));
461 else
462 addr = plus_constant (virtual_stack_vars_rtx,
463 trunc_int_for_mode
464 (function->x_frame_offset + bigend_correction,
465 Pmode));
467 #ifndef FRAME_GROWS_DOWNWARD
468 function->x_frame_offset += size;
469 #endif
471 x = gen_rtx_MEM (mode, addr);
473 function->x_stack_slot_list
474 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
476 return x;
479 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
480 current function. */
483 assign_stack_local (enum machine_mode mode, HOST_WIDE_INT size, int align)
485 return assign_stack_local_1 (mode, size, align, cfun);
489 /* Removes temporary slot TEMP from LIST. */
491 static void
492 cut_slot_from_list (struct temp_slot *temp, struct temp_slot **list)
494 if (temp->next)
495 temp->next->prev = temp->prev;
496 if (temp->prev)
497 temp->prev->next = temp->next;
498 else
499 *list = temp->next;
501 temp->prev = temp->next = NULL;
504 /* Inserts temporary slot TEMP to LIST. */
506 static void
507 insert_slot_to_list (struct temp_slot *temp, struct temp_slot **list)
509 temp->next = *list;
510 if (*list)
511 (*list)->prev = temp;
512 temp->prev = NULL;
513 *list = temp;
516 /* Returns the list of used temp slots at LEVEL. */
518 static struct temp_slot **
519 temp_slots_at_level (int level)
522 if (!used_temp_slots)
523 VARRAY_GENERIC_PTR_INIT (used_temp_slots, 3, "used_temp_slots");
525 while (level >= (int) VARRAY_ACTIVE_SIZE (used_temp_slots))
526 VARRAY_PUSH_GENERIC_PTR (used_temp_slots, NULL);
528 return (struct temp_slot **) &VARRAY_GENERIC_PTR (used_temp_slots, level);
531 /* Returns the maximal temporary slot level. */
533 static int
534 max_slot_level (void)
536 if (!used_temp_slots)
537 return -1;
539 return VARRAY_ACTIVE_SIZE (used_temp_slots) - 1;
542 /* Moves temporary slot TEMP to LEVEL. */
544 static void
545 move_slot_to_level (struct temp_slot *temp, int level)
547 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
548 insert_slot_to_list (temp, temp_slots_at_level (level));
549 temp->level = level;
552 /* Make temporary slot TEMP available. */
554 static void
555 make_slot_available (struct temp_slot *temp)
557 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
558 insert_slot_to_list (temp, &avail_temp_slots);
559 temp->in_use = 0;
560 temp->level = -1;
563 /* Allocate a temporary stack slot and record it for possible later
564 reuse.
566 MODE is the machine mode to be given to the returned rtx.
568 SIZE is the size in units of the space required. We do no rounding here
569 since assign_stack_local will do any required rounding.
571 KEEP is 1 if this slot is to be retained after a call to
572 free_temp_slots. Automatic variables for a block are allocated
573 with this flag. KEEP values of 2 or 3 were needed respectively
574 for variables whose lifetime is controlled by CLEANUP_POINT_EXPRs
575 or for SAVE_EXPRs, but they are now unused.
577 TYPE is the type that will be used for the stack slot. */
580 assign_stack_temp_for_type (enum machine_mode mode, HOST_WIDE_INT size,
581 int keep, tree type)
583 unsigned int align;
584 struct temp_slot *p, *best_p = 0, *selected = NULL, **pp;
585 rtx slot;
587 /* If SIZE is -1 it means that somebody tried to allocate a temporary
588 of a variable size. */
589 gcc_assert (size != -1);
591 /* These are now unused. */
592 gcc_assert (keep <= 1);
594 if (mode == BLKmode)
595 align = BIGGEST_ALIGNMENT;
596 else
597 align = GET_MODE_ALIGNMENT (mode);
599 if (! type)
600 type = lang_hooks.types.type_for_mode (mode, 0);
602 if (type)
603 align = LOCAL_ALIGNMENT (type, align);
605 /* Try to find an available, already-allocated temporary of the proper
606 mode which meets the size and alignment requirements. Choose the
607 smallest one with the closest alignment. */
608 for (p = avail_temp_slots; p; p = p->next)
610 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
611 && objects_must_conflict_p (p->type, type)
612 && (best_p == 0 || best_p->size > p->size
613 || (best_p->size == p->size && best_p->align > p->align)))
615 if (p->align == align && p->size == size)
617 selected = p;
618 cut_slot_from_list (selected, &avail_temp_slots);
619 best_p = 0;
620 break;
622 best_p = p;
626 /* Make our best, if any, the one to use. */
627 if (best_p)
629 selected = best_p;
630 cut_slot_from_list (selected, &avail_temp_slots);
632 /* If there are enough aligned bytes left over, make them into a new
633 temp_slot so that the extra bytes don't get wasted. Do this only
634 for BLKmode slots, so that we can be sure of the alignment. */
635 if (GET_MODE (best_p->slot) == BLKmode)
637 int alignment = best_p->align / BITS_PER_UNIT;
638 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
640 if (best_p->size - rounded_size >= alignment)
642 p = ggc_alloc (sizeof (struct temp_slot));
643 p->in_use = p->addr_taken = 0;
644 p->size = best_p->size - rounded_size;
645 p->base_offset = best_p->base_offset + rounded_size;
646 p->full_size = best_p->full_size - rounded_size;
647 p->slot = gen_rtx_MEM (BLKmode,
648 plus_constant (XEXP (best_p->slot, 0),
649 rounded_size));
650 p->align = best_p->align;
651 p->address = 0;
652 p->type = best_p->type;
653 insert_slot_to_list (p, &avail_temp_slots);
655 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
656 stack_slot_list);
658 best_p->size = rounded_size;
659 best_p->full_size = rounded_size;
664 /* If we still didn't find one, make a new temporary. */
665 if (selected == 0)
667 HOST_WIDE_INT frame_offset_old = frame_offset;
669 p = ggc_alloc (sizeof (struct temp_slot));
671 /* We are passing an explicit alignment request to assign_stack_local.
672 One side effect of that is assign_stack_local will not round SIZE
673 to ensure the frame offset remains suitably aligned.
675 So for requests which depended on the rounding of SIZE, we go ahead
676 and round it now. We also make sure ALIGNMENT is at least
677 BIGGEST_ALIGNMENT. */
678 gcc_assert (mode != BLKmode || align == BIGGEST_ALIGNMENT);
679 p->slot = assign_stack_local (mode,
680 (mode == BLKmode
681 ? CEIL_ROUND (size, (int) align / BITS_PER_UNIT)
682 : size),
683 align);
685 p->align = align;
687 /* The following slot size computation is necessary because we don't
688 know the actual size of the temporary slot until assign_stack_local
689 has performed all the frame alignment and size rounding for the
690 requested temporary. Note that extra space added for alignment
691 can be either above or below this stack slot depending on which
692 way the frame grows. We include the extra space if and only if it
693 is above this slot. */
694 #ifdef FRAME_GROWS_DOWNWARD
695 p->size = frame_offset_old - frame_offset;
696 #else
697 p->size = size;
698 #endif
700 /* Now define the fields used by combine_temp_slots. */
701 #ifdef FRAME_GROWS_DOWNWARD
702 p->base_offset = frame_offset;
703 p->full_size = frame_offset_old - frame_offset;
704 #else
705 p->base_offset = frame_offset_old;
706 p->full_size = frame_offset - frame_offset_old;
707 #endif
708 p->address = 0;
710 selected = p;
713 p = selected;
714 p->in_use = 1;
715 p->addr_taken = 0;
716 p->type = type;
717 p->level = temp_slot_level;
718 p->keep = keep;
720 pp = temp_slots_at_level (p->level);
721 insert_slot_to_list (p, pp);
723 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
724 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
725 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list);
727 /* If we know the alias set for the memory that will be used, use
728 it. If there's no TYPE, then we don't know anything about the
729 alias set for the memory. */
730 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
731 set_mem_align (slot, align);
733 /* If a type is specified, set the relevant flags. */
734 if (type != 0)
736 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
737 MEM_SET_IN_STRUCT_P (slot, AGGREGATE_TYPE_P (type));
740 return slot;
743 /* Allocate a temporary stack slot and record it for possible later
744 reuse. First three arguments are same as in preceding function. */
747 assign_stack_temp (enum machine_mode mode, HOST_WIDE_INT size, int keep)
749 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
752 /* Assign a temporary.
753 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
754 and so that should be used in error messages. In either case, we
755 allocate of the given type.
756 KEEP is as for assign_stack_temp.
757 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
758 it is 0 if a register is OK.
759 DONT_PROMOTE is 1 if we should not promote values in register
760 to wider modes. */
763 assign_temp (tree type_or_decl, int keep, int memory_required,
764 int dont_promote ATTRIBUTE_UNUSED)
766 tree type, decl;
767 enum machine_mode mode;
768 #ifdef PROMOTE_MODE
769 int unsignedp;
770 #endif
772 if (DECL_P (type_or_decl))
773 decl = type_or_decl, type = TREE_TYPE (decl);
774 else
775 decl = NULL, type = type_or_decl;
777 mode = TYPE_MODE (type);
778 #ifdef PROMOTE_MODE
779 unsignedp = TYPE_UNSIGNED (type);
780 #endif
782 if (mode == BLKmode || memory_required)
784 HOST_WIDE_INT size = int_size_in_bytes (type);
785 tree size_tree;
786 rtx tmp;
788 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
789 problems with allocating the stack space. */
790 if (size == 0)
791 size = 1;
793 /* Unfortunately, we don't yet know how to allocate variable-sized
794 temporaries. However, sometimes we have a fixed upper limit on
795 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
796 instead. This is the case for Chill variable-sized strings. */
797 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
798 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
799 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
800 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
802 /* If we still haven't been able to get a size, see if the language
803 can compute a maximum size. */
804 if (size == -1
805 && (size_tree = lang_hooks.types.max_size (type)) != 0
806 && host_integerp (size_tree, 1))
807 size = tree_low_cst (size_tree, 1);
809 /* The size of the temporary may be too large to fit into an integer. */
810 /* ??? Not sure this should happen except for user silliness, so limit
811 this to things that aren't compiler-generated temporaries. The
812 rest of the time we'll die in assign_stack_temp_for_type. */
813 if (decl && size == -1
814 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
816 error ("%Jsize of variable %qD is too large", decl, decl);
817 size = 1;
820 tmp = assign_stack_temp_for_type (mode, size, keep, type);
821 return tmp;
824 #ifdef PROMOTE_MODE
825 if (! dont_promote)
826 mode = promote_mode (type, mode, &unsignedp, 0);
827 #endif
829 return gen_reg_rtx (mode);
832 /* Combine temporary stack slots which are adjacent on the stack.
834 This allows for better use of already allocated stack space. This is only
835 done for BLKmode slots because we can be sure that we won't have alignment
836 problems in this case. */
838 static void
839 combine_temp_slots (void)
841 struct temp_slot *p, *q, *next, *next_q;
842 int num_slots;
844 /* We can't combine slots, because the information about which slot
845 is in which alias set will be lost. */
846 if (flag_strict_aliasing)
847 return;
849 /* If there are a lot of temp slots, don't do anything unless
850 high levels of optimization. */
851 if (! flag_expensive_optimizations)
852 for (p = avail_temp_slots, num_slots = 0; p; p = p->next, num_slots++)
853 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
854 return;
856 for (p = avail_temp_slots; p; p = next)
858 int delete_p = 0;
860 next = p->next;
862 if (GET_MODE (p->slot) != BLKmode)
863 continue;
865 for (q = p->next; q; q = next_q)
867 int delete_q = 0;
869 next_q = q->next;
871 if (GET_MODE (q->slot) != BLKmode)
872 continue;
874 if (p->base_offset + p->full_size == q->base_offset)
876 /* Q comes after P; combine Q into P. */
877 p->size += q->size;
878 p->full_size += q->full_size;
879 delete_q = 1;
881 else if (q->base_offset + q->full_size == p->base_offset)
883 /* P comes after Q; combine P into Q. */
884 q->size += p->size;
885 q->full_size += p->full_size;
886 delete_p = 1;
887 break;
889 if (delete_q)
890 cut_slot_from_list (q, &avail_temp_slots);
893 /* Either delete P or advance past it. */
894 if (delete_p)
895 cut_slot_from_list (p, &avail_temp_slots);
899 /* Find the temp slot corresponding to the object at address X. */
901 static struct temp_slot *
902 find_temp_slot_from_address (rtx x)
904 struct temp_slot *p;
905 rtx next;
906 int i;
908 for (i = max_slot_level (); i >= 0; i--)
909 for (p = *temp_slots_at_level (i); p; p = p->next)
911 if (XEXP (p->slot, 0) == x
912 || p->address == x
913 || (GET_CODE (x) == PLUS
914 && XEXP (x, 0) == virtual_stack_vars_rtx
915 && GET_CODE (XEXP (x, 1)) == CONST_INT
916 && INTVAL (XEXP (x, 1)) >= p->base_offset
917 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
918 return p;
920 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
921 for (next = p->address; next; next = XEXP (next, 1))
922 if (XEXP (next, 0) == x)
923 return p;
926 /* If we have a sum involving a register, see if it points to a temp
927 slot. */
928 if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 0))
929 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
930 return p;
931 else if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 1))
932 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
933 return p;
935 return 0;
938 /* Indicate that NEW is an alternate way of referring to the temp slot
939 that previously was known by OLD. */
941 void
942 update_temp_slot_address (rtx old, rtx new)
944 struct temp_slot *p;
946 if (rtx_equal_p (old, new))
947 return;
949 p = find_temp_slot_from_address (old);
951 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
952 is a register, see if one operand of the PLUS is a temporary
953 location. If so, NEW points into it. Otherwise, if both OLD and
954 NEW are a PLUS and if there is a register in common between them.
955 If so, try a recursive call on those values. */
956 if (p == 0)
958 if (GET_CODE (old) != PLUS)
959 return;
961 if (REG_P (new))
963 update_temp_slot_address (XEXP (old, 0), new);
964 update_temp_slot_address (XEXP (old, 1), new);
965 return;
967 else if (GET_CODE (new) != PLUS)
968 return;
970 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
971 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
972 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
973 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
974 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
975 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
976 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
977 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
979 return;
982 /* Otherwise add an alias for the temp's address. */
983 else if (p->address == 0)
984 p->address = new;
985 else
987 if (GET_CODE (p->address) != EXPR_LIST)
988 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
990 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
994 /* If X could be a reference to a temporary slot, mark the fact that its
995 address was taken. */
997 void
998 mark_temp_addr_taken (rtx x)
1000 struct temp_slot *p;
1002 if (x == 0)
1003 return;
1005 /* If X is not in memory or is at a constant address, it cannot be in
1006 a temporary slot. */
1007 if (!MEM_P (x) || CONSTANT_P (XEXP (x, 0)))
1008 return;
1010 p = find_temp_slot_from_address (XEXP (x, 0));
1011 if (p != 0)
1012 p->addr_taken = 1;
1015 /* If X could be a reference to a temporary slot, mark that slot as
1016 belonging to the to one level higher than the current level. If X
1017 matched one of our slots, just mark that one. Otherwise, we can't
1018 easily predict which it is, so upgrade all of them. Kept slots
1019 need not be touched.
1021 This is called when an ({...}) construct occurs and a statement
1022 returns a value in memory. */
1024 void
1025 preserve_temp_slots (rtx x)
1027 struct temp_slot *p = 0, *next;
1029 /* If there is no result, we still might have some objects whose address
1030 were taken, so we need to make sure they stay around. */
1031 if (x == 0)
1033 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1035 next = p->next;
1037 if (p->addr_taken)
1038 move_slot_to_level (p, temp_slot_level - 1);
1041 return;
1044 /* If X is a register that is being used as a pointer, see if we have
1045 a temporary slot we know it points to. To be consistent with
1046 the code below, we really should preserve all non-kept slots
1047 if we can't find a match, but that seems to be much too costly. */
1048 if (REG_P (x) && REG_POINTER (x))
1049 p = find_temp_slot_from_address (x);
1051 /* If X is not in memory or is at a constant address, it cannot be in
1052 a temporary slot, but it can contain something whose address was
1053 taken. */
1054 if (p == 0 && (!MEM_P (x) || CONSTANT_P (XEXP (x, 0))))
1056 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1058 next = p->next;
1060 if (p->addr_taken)
1061 move_slot_to_level (p, temp_slot_level - 1);
1064 return;
1067 /* First see if we can find a match. */
1068 if (p == 0)
1069 p = find_temp_slot_from_address (XEXP (x, 0));
1071 if (p != 0)
1073 /* Move everything at our level whose address was taken to our new
1074 level in case we used its address. */
1075 struct temp_slot *q;
1077 if (p->level == temp_slot_level)
1079 for (q = *temp_slots_at_level (temp_slot_level); q; q = next)
1081 next = q->next;
1083 if (p != q && q->addr_taken)
1084 move_slot_to_level (q, temp_slot_level - 1);
1087 move_slot_to_level (p, temp_slot_level - 1);
1088 p->addr_taken = 0;
1090 return;
1093 /* Otherwise, preserve all non-kept slots at this level. */
1094 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1096 next = p->next;
1098 if (!p->keep)
1099 move_slot_to_level (p, temp_slot_level - 1);
1103 /* Free all temporaries used so far. This is normally called at the
1104 end of generating code for a statement. */
1106 void
1107 free_temp_slots (void)
1109 struct temp_slot *p, *next;
1111 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1113 next = p->next;
1115 if (!p->keep)
1116 make_slot_available (p);
1119 combine_temp_slots ();
1122 /* Push deeper into the nesting level for stack temporaries. */
1124 void
1125 push_temp_slots (void)
1127 temp_slot_level++;
1130 /* Pop a temporary nesting level. All slots in use in the current level
1131 are freed. */
1133 void
1134 pop_temp_slots (void)
1136 struct temp_slot *p, *next;
1138 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1140 next = p->next;
1141 make_slot_available (p);
1144 combine_temp_slots ();
1146 temp_slot_level--;
1149 /* Initialize temporary slots. */
1151 void
1152 init_temp_slots (void)
1154 /* We have not allocated any temporaries yet. */
1155 avail_temp_slots = 0;
1156 used_temp_slots = 0;
1157 temp_slot_level = 0;
1160 /* These routines are responsible for converting virtual register references
1161 to the actual hard register references once RTL generation is complete.
1163 The following four variables are used for communication between the
1164 routines. They contain the offsets of the virtual registers from their
1165 respective hard registers. */
1167 static int in_arg_offset;
1168 static int var_offset;
1169 static int dynamic_offset;
1170 static int out_arg_offset;
1171 static int cfa_offset;
1173 /* In most machines, the stack pointer register is equivalent to the bottom
1174 of the stack. */
1176 #ifndef STACK_POINTER_OFFSET
1177 #define STACK_POINTER_OFFSET 0
1178 #endif
1180 /* If not defined, pick an appropriate default for the offset of dynamically
1181 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1182 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1184 #ifndef STACK_DYNAMIC_OFFSET
1186 /* The bottom of the stack points to the actual arguments. If
1187 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1188 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1189 stack space for register parameters is not pushed by the caller, but
1190 rather part of the fixed stack areas and hence not included in
1191 `current_function_outgoing_args_size'. Nevertheless, we must allow
1192 for it when allocating stack dynamic objects. */
1194 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
1195 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1196 ((ACCUMULATE_OUTGOING_ARGS \
1197 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
1198 + (STACK_POINTER_OFFSET)) \
1200 #else
1201 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1202 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
1203 + (STACK_POINTER_OFFSET))
1204 #endif
1205 #endif
1207 /* On most machines, the CFA coincides with the first incoming parm. */
1209 #ifndef ARG_POINTER_CFA_OFFSET
1210 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
1211 #endif
1214 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1215 is a virtual register, return the equivalent hard register and set the
1216 offset indirectly through the pointer. Otherwise, return 0. */
1218 static rtx
1219 instantiate_new_reg (rtx x, HOST_WIDE_INT *poffset)
1221 rtx new;
1222 HOST_WIDE_INT offset;
1224 if (x == virtual_incoming_args_rtx)
1225 new = arg_pointer_rtx, offset = in_arg_offset;
1226 else if (x == virtual_stack_vars_rtx)
1227 new = frame_pointer_rtx, offset = var_offset;
1228 else if (x == virtual_stack_dynamic_rtx)
1229 new = stack_pointer_rtx, offset = dynamic_offset;
1230 else if (x == virtual_outgoing_args_rtx)
1231 new = stack_pointer_rtx, offset = out_arg_offset;
1232 else if (x == virtual_cfa_rtx)
1233 new = arg_pointer_rtx, offset = cfa_offset;
1234 else
1235 return NULL_RTX;
1237 *poffset = offset;
1238 return new;
1241 /* A subroutine of instantiate_virtual_regs, called via for_each_rtx.
1242 Instantiate any virtual registers present inside of *LOC. The expression
1243 is simplified, as much as possible, but is not to be considered "valid"
1244 in any sense implied by the target. If any change is made, set CHANGED
1245 to true. */
1247 static int
1248 instantiate_virtual_regs_in_rtx (rtx *loc, void *data)
1250 HOST_WIDE_INT offset;
1251 bool *changed = (bool *) data;
1252 rtx x, new;
1254 x = *loc;
1255 if (x == 0)
1256 return 0;
1258 switch (GET_CODE (x))
1260 case REG:
1261 new = instantiate_new_reg (x, &offset);
1262 if (new)
1264 *loc = plus_constant (new, offset);
1265 if (changed)
1266 *changed = true;
1268 return -1;
1270 case PLUS:
1271 new = instantiate_new_reg (XEXP (x, 0), &offset);
1272 if (new)
1274 new = plus_constant (new, offset);
1275 *loc = simplify_gen_binary (PLUS, GET_MODE (x), new, XEXP (x, 1));
1276 if (changed)
1277 *changed = true;
1278 return -1;
1281 /* FIXME -- from old code */
1282 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1283 we can commute the PLUS and SUBREG because pointers into the
1284 frame are well-behaved. */
1285 break;
1287 default:
1288 break;
1291 return 0;
1294 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1295 matches the predicate for insn CODE operand OPERAND. */
1297 static int
1298 safe_insn_predicate (int code, int operand, rtx x)
1300 const struct insn_operand_data *op_data;
1302 if (code < 0)
1303 return true;
1305 op_data = &insn_data[code].operand[operand];
1306 if (op_data->predicate == NULL)
1307 return true;
1309 return op_data->predicate (x, op_data->mode);
1312 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1313 registers present inside of insn. The result will be a valid insn. */
1315 static void
1316 instantiate_virtual_regs_in_insn (rtx insn)
1318 HOST_WIDE_INT offset;
1319 int insn_code, i;
1320 bool any_change = false;
1321 rtx set, new, x, seq;
1323 /* There are some special cases to be handled first. */
1324 set = single_set (insn);
1325 if (set)
1327 /* We're allowed to assign to a virtual register. This is interpreted
1328 to mean that the underlying register gets assigned the inverse
1329 transformation. This is used, for example, in the handling of
1330 non-local gotos. */
1331 new = instantiate_new_reg (SET_DEST (set), &offset);
1332 if (new)
1334 start_sequence ();
1336 for_each_rtx (&SET_SRC (set), instantiate_virtual_regs_in_rtx, NULL);
1337 x = simplify_gen_binary (PLUS, GET_MODE (new), SET_SRC (set),
1338 GEN_INT (-offset));
1339 x = force_operand (x, new);
1340 if (x != new)
1341 emit_move_insn (new, x);
1343 seq = get_insns ();
1344 end_sequence ();
1346 emit_insn_before (seq, insn);
1347 delete_insn (insn);
1348 return;
1351 /* Handle a straight copy from a virtual register by generating a
1352 new add insn. The difference between this and falling through
1353 to the generic case is avoiding a new pseudo and eliminating a
1354 move insn in the initial rtl stream. */
1355 new = instantiate_new_reg (SET_SRC (set), &offset);
1356 if (new && offset != 0
1357 && REG_P (SET_DEST (set))
1358 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1360 start_sequence ();
1362 x = expand_simple_binop (GET_MODE (SET_DEST (set)), PLUS,
1363 new, GEN_INT (offset), SET_DEST (set),
1364 1, OPTAB_LIB_WIDEN);
1365 if (x != SET_DEST (set))
1366 emit_move_insn (SET_DEST (set), x);
1368 seq = get_insns ();
1369 end_sequence ();
1371 emit_insn_before (seq, insn);
1372 delete_insn (insn);
1373 return;
1376 extract_insn (insn);
1377 insn_code = INSN_CODE (insn);
1379 /* Handle a plus involving a virtual register by determining if the
1380 operands remain valid if they're modified in place. */
1381 if (GET_CODE (SET_SRC (set)) == PLUS
1382 && recog_data.n_operands >= 3
1383 && recog_data.operand_loc[1] == &XEXP (SET_SRC (set), 0)
1384 && recog_data.operand_loc[2] == &XEXP (SET_SRC (set), 1)
1385 && GET_CODE (recog_data.operand[2]) == CONST_INT
1386 && (new = instantiate_new_reg (recog_data.operand[1], &offset)))
1388 offset += INTVAL (recog_data.operand[2]);
1390 /* If the sum is zero, then replace with a plain move. */
1391 if (offset == 0
1392 && REG_P (SET_DEST (set))
1393 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1395 start_sequence ();
1396 emit_move_insn (SET_DEST (set), new);
1397 seq = get_insns ();
1398 end_sequence ();
1400 emit_insn_before (seq, insn);
1401 delete_insn (insn);
1402 return;
1405 x = gen_int_mode (offset, recog_data.operand_mode[2]);
1407 /* Using validate_change and apply_change_group here leaves
1408 recog_data in an invalid state. Since we know exactly what
1409 we want to check, do those two by hand. */
1410 if (safe_insn_predicate (insn_code, 1, new)
1411 && safe_insn_predicate (insn_code, 2, x))
1413 *recog_data.operand_loc[1] = recog_data.operand[1] = new;
1414 *recog_data.operand_loc[2] = recog_data.operand[2] = x;
1415 any_change = true;
1417 /* Fall through into the regular operand fixup loop in
1418 order to take care of operands other than 1 and 2. */
1422 else
1424 extract_insn (insn);
1425 insn_code = INSN_CODE (insn);
1428 /* In the general case, we expect virtual registers to appear only in
1429 operands, and then only as either bare registers or inside memories. */
1430 for (i = 0; i < recog_data.n_operands; ++i)
1432 x = recog_data.operand[i];
1433 switch (GET_CODE (x))
1435 case MEM:
1437 rtx addr = XEXP (x, 0);
1438 bool changed = false;
1440 for_each_rtx (&addr, instantiate_virtual_regs_in_rtx, &changed);
1441 if (!changed)
1442 continue;
1444 start_sequence ();
1445 x = replace_equiv_address (x, addr);
1446 seq = get_insns ();
1447 end_sequence ();
1448 if (seq)
1449 emit_insn_before (seq, insn);
1451 break;
1453 case REG:
1454 new = instantiate_new_reg (x, &offset);
1455 if (new == NULL)
1456 continue;
1457 if (offset == 0)
1458 x = new;
1459 else
1461 start_sequence ();
1463 /* Careful, special mode predicates may have stuff in
1464 insn_data[insn_code].operand[i].mode that isn't useful
1465 to us for computing a new value. */
1466 /* ??? Recognize address_operand and/or "p" constraints
1467 to see if (plus new offset) is a valid before we put
1468 this through expand_simple_binop. */
1469 x = expand_simple_binop (GET_MODE (x), PLUS, new,
1470 GEN_INT (offset), NULL_RTX,
1471 1, OPTAB_LIB_WIDEN);
1472 seq = get_insns ();
1473 end_sequence ();
1474 emit_insn_before (seq, insn);
1476 break;
1478 case SUBREG:
1479 new = instantiate_new_reg (SUBREG_REG (x), &offset);
1480 if (new == NULL)
1481 continue;
1482 if (offset != 0)
1484 start_sequence ();
1485 new = expand_simple_binop (GET_MODE (new), PLUS, new,
1486 GEN_INT (offset), NULL_RTX,
1487 1, OPTAB_LIB_WIDEN);
1488 seq = get_insns ();
1489 end_sequence ();
1490 emit_insn_before (seq, insn);
1492 x = simplify_gen_subreg (recog_data.operand_mode[i], new,
1493 GET_MODE (new), SUBREG_BYTE (x));
1494 break;
1496 default:
1497 continue;
1500 /* At this point, X contains the new value for the operand.
1501 Validate the new value vs the insn predicate. Note that
1502 asm insns will have insn_code -1 here. */
1503 if (!safe_insn_predicate (insn_code, i, x))
1504 x = force_reg (insn_data[insn_code].operand[i].mode, x);
1506 *recog_data.operand_loc[i] = recog_data.operand[i] = x;
1507 any_change = true;
1510 if (any_change)
1512 /* Propagate operand changes into the duplicates. */
1513 for (i = 0; i < recog_data.n_dups; ++i)
1514 *recog_data.dup_loc[i]
1515 = recog_data.operand[(unsigned)recog_data.dup_num[i]];
1517 /* Force re-recognition of the instruction for validation. */
1518 INSN_CODE (insn) = -1;
1521 if (asm_noperands (PATTERN (insn)) >= 0)
1523 if (!check_asm_operands (PATTERN (insn)))
1525 error_for_asm (insn, "impossible constraint in %<asm%>");
1526 delete_insn (insn);
1529 else
1531 if (recog_memoized (insn) < 0)
1532 fatal_insn_not_found (insn);
1536 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1537 do any instantiation required. */
1539 static void
1540 instantiate_decl (rtx x)
1542 rtx addr;
1544 if (x == 0)
1545 return;
1547 /* If this is a CONCAT, recurse for the pieces. */
1548 if (GET_CODE (x) == CONCAT)
1550 instantiate_decl (XEXP (x, 0));
1551 instantiate_decl (XEXP (x, 1));
1552 return;
1555 /* If this is not a MEM, no need to do anything. Similarly if the
1556 address is a constant or a register that is not a virtual register. */
1557 if (!MEM_P (x))
1558 return;
1560 addr = XEXP (x, 0);
1561 if (CONSTANT_P (addr)
1562 || (REG_P (addr)
1563 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
1564 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
1565 return;
1567 for_each_rtx (&XEXP (x, 0), instantiate_virtual_regs_in_rtx, NULL);
1570 /* Subroutine of instantiate_decls: Process all decls in the given
1571 BLOCK node and all its subblocks. */
1573 static void
1574 instantiate_decls_1 (tree let)
1576 tree t;
1578 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
1579 if (DECL_RTL_SET_P (t))
1580 instantiate_decl (DECL_RTL (t));
1582 /* Process all subblocks. */
1583 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
1584 instantiate_decls_1 (t);
1587 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1588 all virtual registers in their DECL_RTL's. */
1590 static void
1591 instantiate_decls (tree fndecl)
1593 tree decl;
1595 /* Process all parameters of the function. */
1596 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
1598 instantiate_decl (DECL_RTL (decl));
1599 instantiate_decl (DECL_INCOMING_RTL (decl));
1602 /* Now process all variables defined in the function or its subblocks. */
1603 instantiate_decls_1 (DECL_INITIAL (fndecl));
1606 /* Pass through the INSNS of function FNDECL and convert virtual register
1607 references to hard register references. */
1609 void
1610 instantiate_virtual_regs (void)
1612 rtx insn;
1614 /* Compute the offsets to use for this function. */
1615 in_arg_offset = FIRST_PARM_OFFSET (current_function_decl);
1616 var_offset = STARTING_FRAME_OFFSET;
1617 dynamic_offset = STACK_DYNAMIC_OFFSET (current_function_decl);
1618 out_arg_offset = STACK_POINTER_OFFSET;
1619 cfa_offset = ARG_POINTER_CFA_OFFSET (current_function_decl);
1621 /* Initialize recognition, indicating that volatile is OK. */
1622 init_recog ();
1624 /* Scan through all the insns, instantiating every virtual register still
1625 present. */
1626 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
1627 if (INSN_P (insn))
1629 /* These patterns in the instruction stream can never be recognized.
1630 Fortunately, they shouldn't contain virtual registers either. */
1631 if (GET_CODE (PATTERN (insn)) == USE
1632 || GET_CODE (PATTERN (insn)) == CLOBBER
1633 || GET_CODE (PATTERN (insn)) == ADDR_VEC
1634 || GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC
1635 || GET_CODE (PATTERN (insn)) == ASM_INPUT)
1636 continue;
1638 instantiate_virtual_regs_in_insn (insn);
1640 if (INSN_DELETED_P (insn))
1641 continue;
1643 for_each_rtx (&REG_NOTES (insn), instantiate_virtual_regs_in_rtx, NULL);
1645 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1646 if (GET_CODE (insn) == CALL_INSN)
1647 for_each_rtx (&CALL_INSN_FUNCTION_USAGE (insn),
1648 instantiate_virtual_regs_in_rtx, NULL);
1651 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1652 instantiate_decls (current_function_decl);
1654 /* Indicate that, from now on, assign_stack_local should use
1655 frame_pointer_rtx. */
1656 virtuals_instantiated = 1;
1659 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
1660 This means a type for which function calls must pass an address to the
1661 function or get an address back from the function.
1662 EXP may be a type node or an expression (whose type is tested). */
1665 aggregate_value_p (tree exp, tree fntype)
1667 int i, regno, nregs;
1668 rtx reg;
1670 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
1672 if (fntype)
1673 switch (TREE_CODE (fntype))
1675 case CALL_EXPR:
1676 fntype = get_callee_fndecl (fntype);
1677 fntype = fntype ? TREE_TYPE (fntype) : 0;
1678 break;
1679 case FUNCTION_DECL:
1680 fntype = TREE_TYPE (fntype);
1681 break;
1682 case FUNCTION_TYPE:
1683 case METHOD_TYPE:
1684 break;
1685 case IDENTIFIER_NODE:
1686 fntype = 0;
1687 break;
1688 default:
1689 /* We don't expect other rtl types here. */
1690 gcc_unreachable ();
1693 if (TREE_CODE (type) == VOID_TYPE)
1694 return 0;
1695 /* If the front end has decided that this needs to be passed by
1696 reference, do so. */
1697 if ((TREE_CODE (exp) == PARM_DECL || TREE_CODE (exp) == RESULT_DECL)
1698 && DECL_BY_REFERENCE (exp))
1699 return 1;
1700 if (targetm.calls.return_in_memory (type, fntype))
1701 return 1;
1702 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
1703 and thus can't be returned in registers. */
1704 if (TREE_ADDRESSABLE (type))
1705 return 1;
1706 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
1707 return 1;
1708 /* Make sure we have suitable call-clobbered regs to return
1709 the value in; if not, we must return it in memory. */
1710 reg = hard_function_value (type, 0, 0);
1712 /* If we have something other than a REG (e.g. a PARALLEL), then assume
1713 it is OK. */
1714 if (!REG_P (reg))
1715 return 0;
1717 regno = REGNO (reg);
1718 nregs = hard_regno_nregs[regno][TYPE_MODE (type)];
1719 for (i = 0; i < nregs; i++)
1720 if (! call_used_regs[regno + i])
1721 return 1;
1722 return 0;
1725 /* Return true if we should assign DECL a pseudo register; false if it
1726 should live on the local stack. */
1728 bool
1729 use_register_for_decl (tree decl)
1731 /* Honor volatile. */
1732 if (TREE_SIDE_EFFECTS (decl))
1733 return false;
1735 /* Honor addressability. */
1736 if (TREE_ADDRESSABLE (decl))
1737 return false;
1739 /* Only register-like things go in registers. */
1740 if (DECL_MODE (decl) == BLKmode)
1741 return false;
1743 /* If -ffloat-store specified, don't put explicit float variables
1744 into registers. */
1745 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
1746 propagates values across these stores, and it probably shouldn't. */
1747 if (flag_float_store && FLOAT_TYPE_P (TREE_TYPE (decl)))
1748 return false;
1750 /* If we're not interested in tracking debugging information for
1751 this decl, then we can certainly put it in a register. */
1752 if (DECL_IGNORED_P (decl))
1753 return true;
1755 return (optimize || DECL_REGISTER (decl));
1758 /* Return true if TYPE should be passed by invisible reference. */
1760 bool
1761 pass_by_reference (CUMULATIVE_ARGS *ca, enum machine_mode mode,
1762 tree type, bool named_arg)
1764 if (type)
1766 /* If this type contains non-trivial constructors, then it is
1767 forbidden for the middle-end to create any new copies. */
1768 if (TREE_ADDRESSABLE (type))
1769 return true;
1771 /* GCC post 3.4 passes *all* variable sized types by reference. */
1772 if (!TYPE_SIZE (type) || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
1773 return true;
1776 return targetm.calls.pass_by_reference (ca, mode, type, named_arg);
1779 /* Return true if TYPE, which is passed by reference, should be callee
1780 copied instead of caller copied. */
1782 bool
1783 reference_callee_copied (CUMULATIVE_ARGS *ca, enum machine_mode mode,
1784 tree type, bool named_arg)
1786 if (type && TREE_ADDRESSABLE (type))
1787 return false;
1788 return targetm.calls.callee_copies (ca, mode, type, named_arg);
1791 /* Structures to communicate between the subroutines of assign_parms.
1792 The first holds data persistent across all parameters, the second
1793 is cleared out for each parameter. */
1795 struct assign_parm_data_all
1797 CUMULATIVE_ARGS args_so_far;
1798 struct args_size stack_args_size;
1799 tree function_result_decl;
1800 tree orig_fnargs;
1801 rtx conversion_insns;
1802 HOST_WIDE_INT pretend_args_size;
1803 HOST_WIDE_INT extra_pretend_bytes;
1804 int reg_parm_stack_space;
1807 struct assign_parm_data_one
1809 tree nominal_type;
1810 tree passed_type;
1811 rtx entry_parm;
1812 rtx stack_parm;
1813 enum machine_mode nominal_mode;
1814 enum machine_mode passed_mode;
1815 enum machine_mode promoted_mode;
1816 struct locate_and_pad_arg_data locate;
1817 int partial;
1818 BOOL_BITFIELD named_arg : 1;
1819 BOOL_BITFIELD passed_pointer : 1;
1820 BOOL_BITFIELD on_stack : 1;
1821 BOOL_BITFIELD loaded_in_reg : 1;
1824 /* A subroutine of assign_parms. Initialize ALL. */
1826 static void
1827 assign_parms_initialize_all (struct assign_parm_data_all *all)
1829 tree fntype;
1831 memset (all, 0, sizeof (*all));
1833 fntype = TREE_TYPE (current_function_decl);
1835 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
1836 INIT_CUMULATIVE_INCOMING_ARGS (all->args_so_far, fntype, NULL_RTX);
1837 #else
1838 INIT_CUMULATIVE_ARGS (all->args_so_far, fntype, NULL_RTX,
1839 current_function_decl, -1);
1840 #endif
1842 #ifdef REG_PARM_STACK_SPACE
1843 all->reg_parm_stack_space = REG_PARM_STACK_SPACE (current_function_decl);
1844 #endif
1847 /* If ARGS contains entries with complex types, split the entry into two
1848 entries of the component type. Return a new list of substitutions are
1849 needed, else the old list. */
1851 static tree
1852 split_complex_args (tree args)
1854 tree p;
1856 /* Before allocating memory, check for the common case of no complex. */
1857 for (p = args; p; p = TREE_CHAIN (p))
1859 tree type = TREE_TYPE (p);
1860 if (TREE_CODE (type) == COMPLEX_TYPE
1861 && targetm.calls.split_complex_arg (type))
1862 goto found;
1864 return args;
1866 found:
1867 args = copy_list (args);
1869 for (p = args; p; p = TREE_CHAIN (p))
1871 tree type = TREE_TYPE (p);
1872 if (TREE_CODE (type) == COMPLEX_TYPE
1873 && targetm.calls.split_complex_arg (type))
1875 tree decl;
1876 tree subtype = TREE_TYPE (type);
1877 bool addressable = TREE_ADDRESSABLE (p);
1879 /* Rewrite the PARM_DECL's type with its component. */
1880 TREE_TYPE (p) = subtype;
1881 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
1882 DECL_MODE (p) = VOIDmode;
1883 DECL_SIZE (p) = NULL;
1884 DECL_SIZE_UNIT (p) = NULL;
1885 /* If this arg must go in memory, put it in a pseudo here.
1886 We can't allow it to go in memory as per normal parms,
1887 because the usual place might not have the imag part
1888 adjacent to the real part. */
1889 DECL_ARTIFICIAL (p) = addressable;
1890 DECL_IGNORED_P (p) = addressable;
1891 TREE_ADDRESSABLE (p) = 0;
1892 layout_decl (p, 0);
1894 /* Build a second synthetic decl. */
1895 decl = build_decl (PARM_DECL, NULL_TREE, subtype);
1896 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
1897 DECL_ARTIFICIAL (decl) = addressable;
1898 DECL_IGNORED_P (decl) = addressable;
1899 layout_decl (decl, 0);
1901 /* Splice it in; skip the new decl. */
1902 TREE_CHAIN (decl) = TREE_CHAIN (p);
1903 TREE_CHAIN (p) = decl;
1904 p = decl;
1908 return args;
1911 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
1912 the hidden struct return argument, and (abi willing) complex args.
1913 Return the new parameter list. */
1915 static tree
1916 assign_parms_augmented_arg_list (struct assign_parm_data_all *all)
1918 tree fndecl = current_function_decl;
1919 tree fntype = TREE_TYPE (fndecl);
1920 tree fnargs = DECL_ARGUMENTS (fndecl);
1922 /* If struct value address is treated as the first argument, make it so. */
1923 if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
1924 && ! current_function_returns_pcc_struct
1925 && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
1927 tree type = build_pointer_type (TREE_TYPE (fntype));
1928 tree decl;
1930 decl = build_decl (PARM_DECL, NULL_TREE, type);
1931 DECL_ARG_TYPE (decl) = type;
1932 DECL_ARTIFICIAL (decl) = 1;
1933 DECL_IGNORED_P (decl) = 1;
1935 TREE_CHAIN (decl) = fnargs;
1936 fnargs = decl;
1937 all->function_result_decl = decl;
1940 all->orig_fnargs = fnargs;
1942 /* If the target wants to split complex arguments into scalars, do so. */
1943 if (targetm.calls.split_complex_arg)
1944 fnargs = split_complex_args (fnargs);
1946 return fnargs;
1949 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
1950 data for the parameter. Incorporate ABI specifics such as pass-by-
1951 reference and type promotion. */
1953 static void
1954 assign_parm_find_data_types (struct assign_parm_data_all *all, tree parm,
1955 struct assign_parm_data_one *data)
1957 tree nominal_type, passed_type;
1958 enum machine_mode nominal_mode, passed_mode, promoted_mode;
1960 memset (data, 0, sizeof (*data));
1962 /* NAMED_ARG is a mis-nomer. We really mean 'non-varadic'. */
1963 if (!current_function_stdarg)
1964 data->named_arg = 1; /* No varadic parms. */
1965 else if (TREE_CHAIN (parm))
1966 data->named_arg = 1; /* Not the last non-varadic parm. */
1967 else if (targetm.calls.strict_argument_naming (&all->args_so_far))
1968 data->named_arg = 1; /* Only varadic ones are unnamed. */
1969 else
1970 data->named_arg = 0; /* Treat as varadic. */
1972 nominal_type = TREE_TYPE (parm);
1973 passed_type = DECL_ARG_TYPE (parm);
1975 /* Look out for errors propagating this far. Also, if the parameter's
1976 type is void then its value doesn't matter. */
1977 if (TREE_TYPE (parm) == error_mark_node
1978 /* This can happen after weird syntax errors
1979 or if an enum type is defined among the parms. */
1980 || TREE_CODE (parm) != PARM_DECL
1981 || passed_type == NULL
1982 || VOID_TYPE_P (nominal_type))
1984 nominal_type = passed_type = void_type_node;
1985 nominal_mode = passed_mode = promoted_mode = VOIDmode;
1986 goto egress;
1989 /* Find mode of arg as it is passed, and mode of arg as it should be
1990 during execution of this function. */
1991 passed_mode = TYPE_MODE (passed_type);
1992 nominal_mode = TYPE_MODE (nominal_type);
1994 /* If the parm is to be passed as a transparent union, use the type of
1995 the first field for the tests below. We have already verified that
1996 the modes are the same. */
1997 if (DECL_TRANSPARENT_UNION (parm)
1998 || (TREE_CODE (passed_type) == UNION_TYPE
1999 && TYPE_TRANSPARENT_UNION (passed_type)))
2000 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
2002 /* See if this arg was passed by invisible reference. */
2003 if (pass_by_reference (&all->args_so_far, passed_mode,
2004 passed_type, data->named_arg))
2006 passed_type = nominal_type = build_pointer_type (passed_type);
2007 data->passed_pointer = true;
2008 passed_mode = nominal_mode = Pmode;
2011 /* Find mode as it is passed by the ABI. */
2012 promoted_mode = passed_mode;
2013 if (targetm.calls.promote_function_args (TREE_TYPE (current_function_decl)))
2015 int unsignedp = TYPE_UNSIGNED (passed_type);
2016 promoted_mode = promote_mode (passed_type, promoted_mode,
2017 &unsignedp, 1);
2020 egress:
2021 data->nominal_type = nominal_type;
2022 data->passed_type = passed_type;
2023 data->nominal_mode = nominal_mode;
2024 data->passed_mode = passed_mode;
2025 data->promoted_mode = promoted_mode;
2028 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2030 static void
2031 assign_parms_setup_varargs (struct assign_parm_data_all *all,
2032 struct assign_parm_data_one *data, bool no_rtl)
2034 int varargs_pretend_bytes = 0;
2036 targetm.calls.setup_incoming_varargs (&all->args_so_far,
2037 data->promoted_mode,
2038 data->passed_type,
2039 &varargs_pretend_bytes, no_rtl);
2041 /* If the back-end has requested extra stack space, record how much is
2042 needed. Do not change pretend_args_size otherwise since it may be
2043 nonzero from an earlier partial argument. */
2044 if (varargs_pretend_bytes > 0)
2045 all->pretend_args_size = varargs_pretend_bytes;
2048 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2049 the incoming location of the current parameter. */
2051 static void
2052 assign_parm_find_entry_rtl (struct assign_parm_data_all *all,
2053 struct assign_parm_data_one *data)
2055 HOST_WIDE_INT pretend_bytes = 0;
2056 rtx entry_parm;
2057 bool in_regs;
2059 if (data->promoted_mode == VOIDmode)
2061 data->entry_parm = data->stack_parm = const0_rtx;
2062 return;
2065 #ifdef FUNCTION_INCOMING_ARG
2066 entry_parm = FUNCTION_INCOMING_ARG (all->args_so_far, data->promoted_mode,
2067 data->passed_type, data->named_arg);
2068 #else
2069 entry_parm = FUNCTION_ARG (all->args_so_far, data->promoted_mode,
2070 data->passed_type, data->named_arg);
2071 #endif
2073 if (entry_parm == 0)
2074 data->promoted_mode = data->passed_mode;
2076 /* Determine parm's home in the stack, in case it arrives in the stack
2077 or we should pretend it did. Compute the stack position and rtx where
2078 the argument arrives and its size.
2080 There is one complexity here: If this was a parameter that would
2081 have been passed in registers, but wasn't only because it is
2082 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2083 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2084 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2085 as it was the previous time. */
2086 in_regs = entry_parm != 0;
2087 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2088 in_regs = true;
2089 #endif
2090 if (!in_regs && !data->named_arg)
2092 if (targetm.calls.pretend_outgoing_varargs_named (&all->args_so_far))
2094 rtx tem;
2095 #ifdef FUNCTION_INCOMING_ARG
2096 tem = FUNCTION_INCOMING_ARG (all->args_so_far, data->promoted_mode,
2097 data->passed_type, true);
2098 #else
2099 tem = FUNCTION_ARG (all->args_so_far, data->promoted_mode,
2100 data->passed_type, true);
2101 #endif
2102 in_regs = tem != NULL;
2106 /* If this parameter was passed both in registers and in the stack, use
2107 the copy on the stack. */
2108 if (targetm.calls.must_pass_in_stack (data->promoted_mode,
2109 data->passed_type))
2110 entry_parm = 0;
2112 if (entry_parm)
2114 int partial;
2116 partial = targetm.calls.arg_partial_bytes (&all->args_so_far,
2117 data->promoted_mode,
2118 data->passed_type,
2119 data->named_arg);
2120 data->partial = partial;
2122 /* The caller might already have allocated stack space for the
2123 register parameters. */
2124 if (partial != 0 && all->reg_parm_stack_space == 0)
2126 /* Part of this argument is passed in registers and part
2127 is passed on the stack. Ask the prologue code to extend
2128 the stack part so that we can recreate the full value.
2130 PRETEND_BYTES is the size of the registers we need to store.
2131 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2132 stack space that the prologue should allocate.
2134 Internally, gcc assumes that the argument pointer is aligned
2135 to STACK_BOUNDARY bits. This is used both for alignment
2136 optimizations (see init_emit) and to locate arguments that are
2137 aligned to more than PARM_BOUNDARY bits. We must preserve this
2138 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2139 a stack boundary. */
2141 /* We assume at most one partial arg, and it must be the first
2142 argument on the stack. */
2143 gcc_assert (!all->extra_pretend_bytes && !all->pretend_args_size);
2145 pretend_bytes = partial;
2146 all->pretend_args_size = CEIL_ROUND (pretend_bytes, STACK_BYTES);
2148 /* We want to align relative to the actual stack pointer, so
2149 don't include this in the stack size until later. */
2150 all->extra_pretend_bytes = all->pretend_args_size;
2154 locate_and_pad_parm (data->promoted_mode, data->passed_type, in_regs,
2155 entry_parm ? data->partial : 0, current_function_decl,
2156 &all->stack_args_size, &data->locate);
2158 /* Adjust offsets to include the pretend args. */
2159 pretend_bytes = all->extra_pretend_bytes - pretend_bytes;
2160 data->locate.slot_offset.constant += pretend_bytes;
2161 data->locate.offset.constant += pretend_bytes;
2163 data->entry_parm = entry_parm;
2166 /* A subroutine of assign_parms. If there is actually space on the stack
2167 for this parm, count it in stack_args_size and return true. */
2169 static bool
2170 assign_parm_is_stack_parm (struct assign_parm_data_all *all,
2171 struct assign_parm_data_one *data)
2173 /* Trivially true if we've no incoming register. */
2174 if (data->entry_parm == NULL)
2176 /* Also true if we're partially in registers and partially not,
2177 since we've arranged to drop the entire argument on the stack. */
2178 else if (data->partial != 0)
2180 /* Also true if the target says that it's passed in both registers
2181 and on the stack. */
2182 else if (GET_CODE (data->entry_parm) == PARALLEL
2183 && XEXP (XVECEXP (data->entry_parm, 0, 0), 0) == NULL_RTX)
2185 /* Also true if the target says that there's stack allocated for
2186 all register parameters. */
2187 else if (all->reg_parm_stack_space > 0)
2189 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2190 else
2191 return false;
2193 all->stack_args_size.constant += data->locate.size.constant;
2194 if (data->locate.size.var)
2195 ADD_PARM_SIZE (all->stack_args_size, data->locate.size.var);
2197 return true;
2200 /* A subroutine of assign_parms. Given that this parameter is allocated
2201 stack space by the ABI, find it. */
2203 static void
2204 assign_parm_find_stack_rtl (tree parm, struct assign_parm_data_one *data)
2206 rtx offset_rtx, stack_parm;
2207 unsigned int align, boundary;
2209 /* If we're passing this arg using a reg, make its stack home the
2210 aligned stack slot. */
2211 if (data->entry_parm)
2212 offset_rtx = ARGS_SIZE_RTX (data->locate.slot_offset);
2213 else
2214 offset_rtx = ARGS_SIZE_RTX (data->locate.offset);
2216 stack_parm = current_function_internal_arg_pointer;
2217 if (offset_rtx != const0_rtx)
2218 stack_parm = gen_rtx_PLUS (Pmode, stack_parm, offset_rtx);
2219 stack_parm = gen_rtx_MEM (data->promoted_mode, stack_parm);
2221 set_mem_attributes (stack_parm, parm, 1);
2223 boundary = data->locate.boundary;
2224 align = BITS_PER_UNIT;
2226 /* If we're padding upward, we know that the alignment of the slot
2227 is FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2228 intentionally forcing upward padding. Otherwise we have to come
2229 up with a guess at the alignment based on OFFSET_RTX. */
2230 if (data->locate.where_pad != downward || data->entry_parm)
2231 align = boundary;
2232 else if (GET_CODE (offset_rtx) == CONST_INT)
2234 align = INTVAL (offset_rtx) * BITS_PER_UNIT | boundary;
2235 align = align & -align;
2237 set_mem_align (stack_parm, align);
2239 if (data->entry_parm)
2240 set_reg_attrs_for_parm (data->entry_parm, stack_parm);
2242 data->stack_parm = stack_parm;
2245 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2246 always valid and contiguous. */
2248 static void
2249 assign_parm_adjust_entry_rtl (struct assign_parm_data_one *data)
2251 rtx entry_parm = data->entry_parm;
2252 rtx stack_parm = data->stack_parm;
2254 /* If this parm was passed part in regs and part in memory, pretend it
2255 arrived entirely in memory by pushing the register-part onto the stack.
2256 In the special case of a DImode or DFmode that is split, we could put
2257 it together in a pseudoreg directly, but for now that's not worth
2258 bothering with. */
2259 if (data->partial != 0)
2261 /* Handle calls that pass values in multiple non-contiguous
2262 locations. The Irix 6 ABI has examples of this. */
2263 if (GET_CODE (entry_parm) == PARALLEL)
2264 emit_group_store (validize_mem (stack_parm), entry_parm,
2265 data->passed_type,
2266 int_size_in_bytes (data->passed_type));
2267 else
2269 gcc_assert (data->partial % UNITS_PER_WORD == 0);
2270 move_block_from_reg (REGNO (entry_parm), validize_mem (stack_parm),
2271 data->partial / UNITS_PER_WORD);
2274 entry_parm = stack_parm;
2277 /* If we didn't decide this parm came in a register, by default it came
2278 on the stack. */
2279 else if (entry_parm == NULL)
2280 entry_parm = stack_parm;
2282 /* When an argument is passed in multiple locations, we can't make use
2283 of this information, but we can save some copying if the whole argument
2284 is passed in a single register. */
2285 else if (GET_CODE (entry_parm) == PARALLEL
2286 && data->nominal_mode != BLKmode
2287 && data->passed_mode != BLKmode)
2289 size_t i, len = XVECLEN (entry_parm, 0);
2291 for (i = 0; i < len; i++)
2292 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
2293 && REG_P (XEXP (XVECEXP (entry_parm, 0, i), 0))
2294 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
2295 == data->passed_mode)
2296 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
2298 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
2299 break;
2303 data->entry_parm = entry_parm;
2306 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2307 always valid and properly aligned. */
2309 static void
2310 assign_parm_adjust_stack_rtl (struct assign_parm_data_one *data)
2312 rtx stack_parm = data->stack_parm;
2314 /* If we can't trust the parm stack slot to be aligned enough for its
2315 ultimate type, don't use that slot after entry. We'll make another
2316 stack slot, if we need one. */
2317 if (stack_parm
2318 && ((STRICT_ALIGNMENT
2319 && GET_MODE_ALIGNMENT (data->nominal_mode) > MEM_ALIGN (stack_parm))
2320 || (data->nominal_type
2321 && TYPE_ALIGN (data->nominal_type) > MEM_ALIGN (stack_parm)
2322 && MEM_ALIGN (stack_parm) < PREFERRED_STACK_BOUNDARY)))
2323 stack_parm = NULL;
2325 /* If parm was passed in memory, and we need to convert it on entry,
2326 don't store it back in that same slot. */
2327 else if (data->entry_parm == stack_parm
2328 && data->nominal_mode != BLKmode
2329 && data->nominal_mode != data->passed_mode)
2330 stack_parm = NULL;
2332 data->stack_parm = stack_parm;
2335 /* A subroutine of assign_parms. Return true if the current parameter
2336 should be stored as a BLKmode in the current frame. */
2338 static bool
2339 assign_parm_setup_block_p (struct assign_parm_data_one *data)
2341 if (data->nominal_mode == BLKmode)
2342 return true;
2343 if (GET_CODE (data->entry_parm) == PARALLEL)
2344 return true;
2346 #ifdef BLOCK_REG_PADDING
2347 /* Only assign_parm_setup_block knows how to deal with register arguments
2348 that are padded at the least significant end. */
2349 if (REG_P (data->entry_parm)
2350 && GET_MODE_SIZE (data->promoted_mode) < UNITS_PER_WORD
2351 && (BLOCK_REG_PADDING (data->passed_mode, data->passed_type, 1)
2352 == (BYTES_BIG_ENDIAN ? upward : downward)))
2353 return true;
2354 #endif
2356 return false;
2359 /* A subroutine of assign_parms. Arrange for the parameter to be
2360 present and valid in DATA->STACK_RTL. */
2362 static void
2363 assign_parm_setup_block (struct assign_parm_data_all *all,
2364 tree parm, struct assign_parm_data_one *data)
2366 rtx entry_parm = data->entry_parm;
2367 rtx stack_parm = data->stack_parm;
2368 HOST_WIDE_INT size;
2369 HOST_WIDE_INT size_stored;
2370 rtx orig_entry_parm = entry_parm;
2372 if (GET_CODE (entry_parm) == PARALLEL)
2373 entry_parm = emit_group_move_into_temps (entry_parm);
2375 /* If we've a non-block object that's nevertheless passed in parts,
2376 reconstitute it in register operations rather than on the stack. */
2377 if (GET_CODE (entry_parm) == PARALLEL
2378 && data->nominal_mode != BLKmode)
2380 rtx elt0 = XEXP (XVECEXP (orig_entry_parm, 0, 0), 0);
2382 if ((XVECLEN (entry_parm, 0) > 1
2383 || hard_regno_nregs[REGNO (elt0)][GET_MODE (elt0)] > 1)
2384 && use_register_for_decl (parm))
2386 rtx parmreg = gen_reg_rtx (data->nominal_mode);
2388 push_to_sequence (all->conversion_insns);
2390 /* For values returned in multiple registers, handle possible
2391 incompatible calls to emit_group_store.
2393 For example, the following would be invalid, and would have to
2394 be fixed by the conditional below:
2396 emit_group_store ((reg:SF), (parallel:DF))
2397 emit_group_store ((reg:SI), (parallel:DI))
2399 An example of this are doubles in e500 v2:
2400 (parallel:DF (expr_list (reg:SI) (const_int 0))
2401 (expr_list (reg:SI) (const_int 4))). */
2402 if (data->nominal_mode != data->passed_mode)
2404 rtx t = gen_reg_rtx (GET_MODE (entry_parm));
2405 emit_group_store (t, entry_parm, NULL_TREE,
2406 GET_MODE_SIZE (GET_MODE (entry_parm)));
2407 convert_move (parmreg, t, 0);
2409 else
2410 emit_group_store (parmreg, entry_parm, data->nominal_type,
2411 int_size_in_bytes (data->nominal_type));
2413 all->conversion_insns = get_insns ();
2414 end_sequence ();
2416 SET_DECL_RTL (parm, parmreg);
2417 return;
2421 size = int_size_in_bytes (data->passed_type);
2422 size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
2423 if (stack_parm == 0)
2425 DECL_ALIGN (parm) = MAX (DECL_ALIGN (parm), BITS_PER_WORD);
2426 stack_parm = assign_stack_local (BLKmode, size_stored,
2427 DECL_ALIGN (parm));
2428 if (GET_MODE_SIZE (GET_MODE (entry_parm)) == size)
2429 PUT_MODE (stack_parm, GET_MODE (entry_parm));
2430 set_mem_attributes (stack_parm, parm, 1);
2433 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2434 calls that pass values in multiple non-contiguous locations. */
2435 if (REG_P (entry_parm) || GET_CODE (entry_parm) == PARALLEL)
2437 rtx mem;
2439 /* Note that we will be storing an integral number of words.
2440 So we have to be careful to ensure that we allocate an
2441 integral number of words. We do this above when we call
2442 assign_stack_local if space was not allocated in the argument
2443 list. If it was, this will not work if PARM_BOUNDARY is not
2444 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2445 if it becomes a problem. Exception is when BLKmode arrives
2446 with arguments not conforming to word_mode. */
2448 if (data->stack_parm == 0)
2450 else if (GET_CODE (entry_parm) == PARALLEL)
2452 else
2453 gcc_assert (!size || !(PARM_BOUNDARY % BITS_PER_WORD));
2455 mem = validize_mem (stack_parm);
2457 /* Handle values in multiple non-contiguous locations. */
2458 if (GET_CODE (entry_parm) == PARALLEL)
2460 push_to_sequence (all->conversion_insns);
2461 emit_group_store (mem, entry_parm, data->passed_type, size);
2462 all->conversion_insns = get_insns ();
2463 end_sequence ();
2466 else if (size == 0)
2469 /* If SIZE is that of a mode no bigger than a word, just use
2470 that mode's store operation. */
2471 else if (size <= UNITS_PER_WORD)
2473 enum machine_mode mode
2474 = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
2476 if (mode != BLKmode
2477 #ifdef BLOCK_REG_PADDING
2478 && (size == UNITS_PER_WORD
2479 || (BLOCK_REG_PADDING (mode, data->passed_type, 1)
2480 != (BYTES_BIG_ENDIAN ? upward : downward)))
2481 #endif
2484 rtx reg = gen_rtx_REG (mode, REGNO (entry_parm));
2485 emit_move_insn (change_address (mem, mode, 0), reg);
2488 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
2489 machine must be aligned to the left before storing
2490 to memory. Note that the previous test doesn't
2491 handle all cases (e.g. SIZE == 3). */
2492 else if (size != UNITS_PER_WORD
2493 #ifdef BLOCK_REG_PADDING
2494 && (BLOCK_REG_PADDING (mode, data->passed_type, 1)
2495 == downward)
2496 #else
2497 && BYTES_BIG_ENDIAN
2498 #endif
2501 rtx tem, x;
2502 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2503 rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
2505 x = expand_shift (LSHIFT_EXPR, word_mode, reg,
2506 build_int_cst (NULL_TREE, by),
2507 NULL_RTX, 1);
2508 tem = change_address (mem, word_mode, 0);
2509 emit_move_insn (tem, x);
2511 else
2512 move_block_from_reg (REGNO (entry_parm), mem,
2513 size_stored / UNITS_PER_WORD);
2515 else
2516 move_block_from_reg (REGNO (entry_parm), mem,
2517 size_stored / UNITS_PER_WORD);
2519 else if (data->stack_parm == 0)
2521 push_to_sequence (all->conversion_insns);
2522 emit_block_move (stack_parm, data->entry_parm, GEN_INT (size),
2523 BLOCK_OP_NORMAL);
2524 all->conversion_insns = get_insns ();
2525 end_sequence ();
2528 data->stack_parm = stack_parm;
2529 SET_DECL_RTL (parm, stack_parm);
2532 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
2533 parameter. Get it there. Perform all ABI specified conversions. */
2535 static void
2536 assign_parm_setup_reg (struct assign_parm_data_all *all, tree parm,
2537 struct assign_parm_data_one *data)
2539 rtx parmreg;
2540 enum machine_mode promoted_nominal_mode;
2541 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (parm));
2542 bool did_conversion = false;
2544 /* Store the parm in a pseudoregister during the function, but we may
2545 need to do it in a wider mode. */
2547 promoted_nominal_mode
2548 = promote_mode (data->nominal_type, data->nominal_mode, &unsignedp, 0);
2550 parmreg = gen_reg_rtx (promoted_nominal_mode);
2552 if (!DECL_ARTIFICIAL (parm))
2553 mark_user_reg (parmreg);
2555 /* If this was an item that we received a pointer to,
2556 set DECL_RTL appropriately. */
2557 if (data->passed_pointer)
2559 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data->passed_type)), parmreg);
2560 set_mem_attributes (x, parm, 1);
2561 SET_DECL_RTL (parm, x);
2563 else
2564 SET_DECL_RTL (parm, parmreg);
2566 /* Copy the value into the register. */
2567 if (data->nominal_mode != data->passed_mode
2568 || promoted_nominal_mode != data->promoted_mode)
2570 int save_tree_used;
2572 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
2573 mode, by the caller. We now have to convert it to
2574 NOMINAL_MODE, if different. However, PARMREG may be in
2575 a different mode than NOMINAL_MODE if it is being stored
2576 promoted.
2578 If ENTRY_PARM is a hard register, it might be in a register
2579 not valid for operating in its mode (e.g., an odd-numbered
2580 register for a DFmode). In that case, moves are the only
2581 thing valid, so we can't do a convert from there. This
2582 occurs when the calling sequence allow such misaligned
2583 usages.
2585 In addition, the conversion may involve a call, which could
2586 clobber parameters which haven't been copied to pseudo
2587 registers yet. Therefore, we must first copy the parm to
2588 a pseudo reg here, and save the conversion until after all
2589 parameters have been moved. */
2591 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
2593 emit_move_insn (tempreg, validize_mem (data->entry_parm));
2595 push_to_sequence (all->conversion_insns);
2596 tempreg = convert_to_mode (data->nominal_mode, tempreg, unsignedp);
2598 if (GET_CODE (tempreg) == SUBREG
2599 && GET_MODE (tempreg) == data->nominal_mode
2600 && REG_P (SUBREG_REG (tempreg))
2601 && data->nominal_mode == data->passed_mode
2602 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (data->entry_parm)
2603 && GET_MODE_SIZE (GET_MODE (tempreg))
2604 < GET_MODE_SIZE (GET_MODE (data->entry_parm)))
2606 /* The argument is already sign/zero extended, so note it
2607 into the subreg. */
2608 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
2609 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
2612 /* TREE_USED gets set erroneously during expand_assignment. */
2613 save_tree_used = TREE_USED (parm);
2614 expand_assignment (parm, make_tree (data->nominal_type, tempreg));
2615 TREE_USED (parm) = save_tree_used;
2616 all->conversion_insns = get_insns ();
2617 end_sequence ();
2619 did_conversion = true;
2621 else
2622 emit_move_insn (parmreg, validize_mem (data->entry_parm));
2624 /* If we were passed a pointer but the actual value can safely live
2625 in a register, put it in one. */
2626 if (data->passed_pointer
2627 && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
2628 /* If by-reference argument was promoted, demote it. */
2629 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
2630 || use_register_for_decl (parm)))
2632 /* We can't use nominal_mode, because it will have been set to
2633 Pmode above. We must use the actual mode of the parm. */
2634 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
2635 mark_user_reg (parmreg);
2637 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
2639 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
2640 int unsigned_p = TYPE_UNSIGNED (TREE_TYPE (parm));
2642 push_to_sequence (all->conversion_insns);
2643 emit_move_insn (tempreg, DECL_RTL (parm));
2644 tempreg = convert_to_mode (GET_MODE (parmreg), tempreg, unsigned_p);
2645 emit_move_insn (parmreg, tempreg);
2646 all->conversion_insns = get_insns ();
2647 end_sequence ();
2649 did_conversion = true;
2651 else
2652 emit_move_insn (parmreg, DECL_RTL (parm));
2654 SET_DECL_RTL (parm, parmreg);
2656 /* STACK_PARM is the pointer, not the parm, and PARMREG is
2657 now the parm. */
2658 data->stack_parm = NULL;
2661 /* Mark the register as eliminable if we did no conversion and it was
2662 copied from memory at a fixed offset, and the arg pointer was not
2663 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
2664 offset formed an invalid address, such memory-equivalences as we
2665 make here would screw up life analysis for it. */
2666 if (data->nominal_mode == data->passed_mode
2667 && !did_conversion
2668 && data->stack_parm != 0
2669 && MEM_P (data->stack_parm)
2670 && data->locate.offset.var == 0
2671 && reg_mentioned_p (virtual_incoming_args_rtx,
2672 XEXP (data->stack_parm, 0)))
2674 rtx linsn = get_last_insn ();
2675 rtx sinsn, set;
2677 /* Mark complex types separately. */
2678 if (GET_CODE (parmreg) == CONCAT)
2680 enum machine_mode submode
2681 = GET_MODE_INNER (GET_MODE (parmreg));
2682 int regnor = REGNO (XEXP (parmreg, 0));
2683 int regnoi = REGNO (XEXP (parmreg, 1));
2684 rtx stackr = adjust_address_nv (data->stack_parm, submode, 0);
2685 rtx stacki = adjust_address_nv (data->stack_parm, submode,
2686 GET_MODE_SIZE (submode));
2688 /* Scan backwards for the set of the real and
2689 imaginary parts. */
2690 for (sinsn = linsn; sinsn != 0;
2691 sinsn = prev_nonnote_insn (sinsn))
2693 set = single_set (sinsn);
2694 if (set == 0)
2695 continue;
2697 if (SET_DEST (set) == regno_reg_rtx [regnoi])
2698 REG_NOTES (sinsn)
2699 = gen_rtx_EXPR_LIST (REG_EQUIV, stacki,
2700 REG_NOTES (sinsn));
2701 else if (SET_DEST (set) == regno_reg_rtx [regnor])
2702 REG_NOTES (sinsn)
2703 = gen_rtx_EXPR_LIST (REG_EQUIV, stackr,
2704 REG_NOTES (sinsn));
2707 else if ((set = single_set (linsn)) != 0
2708 && SET_DEST (set) == parmreg)
2709 REG_NOTES (linsn)
2710 = gen_rtx_EXPR_LIST (REG_EQUIV,
2711 data->stack_parm, REG_NOTES (linsn));
2714 /* For pointer data type, suggest pointer register. */
2715 if (POINTER_TYPE_P (TREE_TYPE (parm)))
2716 mark_reg_pointer (parmreg,
2717 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
2720 /* A subroutine of assign_parms. Allocate stack space to hold the current
2721 parameter. Get it there. Perform all ABI specified conversions. */
2723 static void
2724 assign_parm_setup_stack (struct assign_parm_data_all *all, tree parm,
2725 struct assign_parm_data_one *data)
2727 /* Value must be stored in the stack slot STACK_PARM during function
2728 execution. */
2729 bool to_conversion = false;
2731 if (data->promoted_mode != data->nominal_mode)
2733 /* Conversion is required. */
2734 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
2736 emit_move_insn (tempreg, validize_mem (data->entry_parm));
2738 push_to_sequence (all->conversion_insns);
2739 to_conversion = true;
2741 data->entry_parm = convert_to_mode (data->nominal_mode, tempreg,
2742 TYPE_UNSIGNED (TREE_TYPE (parm)));
2744 if (data->stack_parm)
2745 /* ??? This may need a big-endian conversion on sparc64. */
2746 data->stack_parm
2747 = adjust_address (data->stack_parm, data->nominal_mode, 0);
2750 if (data->entry_parm != data->stack_parm)
2752 rtx src, dest;
2754 if (data->stack_parm == 0)
2756 data->stack_parm
2757 = assign_stack_local (GET_MODE (data->entry_parm),
2758 GET_MODE_SIZE (GET_MODE (data->entry_parm)),
2759 TYPE_ALIGN (data->passed_type));
2760 set_mem_attributes (data->stack_parm, parm, 1);
2763 dest = validize_mem (data->stack_parm);
2764 src = validize_mem (data->entry_parm);
2766 if (MEM_P (src))
2768 /* Use a block move to handle potentially misaligned entry_parm. */
2769 if (!to_conversion)
2770 push_to_sequence (all->conversion_insns);
2771 to_conversion = true;
2773 emit_block_move (dest, src,
2774 GEN_INT (int_size_in_bytes (data->passed_type)),
2775 BLOCK_OP_NORMAL);
2777 else
2778 emit_move_insn (dest, src);
2781 if (to_conversion)
2783 all->conversion_insns = get_insns ();
2784 end_sequence ();
2787 SET_DECL_RTL (parm, data->stack_parm);
2790 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
2791 undo the frobbing that we did in assign_parms_augmented_arg_list. */
2793 static void
2794 assign_parms_unsplit_complex (struct assign_parm_data_all *all, tree fnargs)
2796 tree parm;
2797 tree orig_fnargs = all->orig_fnargs;
2799 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm))
2801 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE
2802 && targetm.calls.split_complex_arg (TREE_TYPE (parm)))
2804 rtx tmp, real, imag;
2805 enum machine_mode inner = GET_MODE_INNER (DECL_MODE (parm));
2807 real = DECL_RTL (fnargs);
2808 imag = DECL_RTL (TREE_CHAIN (fnargs));
2809 if (inner != GET_MODE (real))
2811 real = gen_lowpart_SUBREG (inner, real);
2812 imag = gen_lowpart_SUBREG (inner, imag);
2815 if (TREE_ADDRESSABLE (parm))
2817 rtx rmem, imem;
2818 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (parm));
2820 /* split_complex_arg put the real and imag parts in
2821 pseudos. Move them to memory. */
2822 tmp = assign_stack_local (DECL_MODE (parm), size,
2823 TYPE_ALIGN (TREE_TYPE (parm)));
2824 set_mem_attributes (tmp, parm, 1);
2825 rmem = adjust_address_nv (tmp, inner, 0);
2826 imem = adjust_address_nv (tmp, inner, GET_MODE_SIZE (inner));
2827 push_to_sequence (all->conversion_insns);
2828 emit_move_insn (rmem, real);
2829 emit_move_insn (imem, imag);
2830 all->conversion_insns = get_insns ();
2831 end_sequence ();
2833 else
2834 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
2835 SET_DECL_RTL (parm, tmp);
2837 real = DECL_INCOMING_RTL (fnargs);
2838 imag = DECL_INCOMING_RTL (TREE_CHAIN (fnargs));
2839 if (inner != GET_MODE (real))
2841 real = gen_lowpart_SUBREG (inner, real);
2842 imag = gen_lowpart_SUBREG (inner, imag);
2844 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
2845 set_decl_incoming_rtl (parm, tmp);
2846 fnargs = TREE_CHAIN (fnargs);
2848 else
2850 SET_DECL_RTL (parm, DECL_RTL (fnargs));
2851 set_decl_incoming_rtl (parm, DECL_INCOMING_RTL (fnargs));
2853 /* Set MEM_EXPR to the original decl, i.e. to PARM,
2854 instead of the copy of decl, i.e. FNARGS. */
2855 if (DECL_INCOMING_RTL (parm) && MEM_P (DECL_INCOMING_RTL (parm)))
2856 set_mem_expr (DECL_INCOMING_RTL (parm), parm);
2859 fnargs = TREE_CHAIN (fnargs);
2863 /* Assign RTL expressions to the function's parameters. This may involve
2864 copying them into registers and using those registers as the DECL_RTL. */
2866 static void
2867 assign_parms (tree fndecl)
2869 struct assign_parm_data_all all;
2870 tree fnargs, parm;
2871 rtx internal_arg_pointer;
2873 /* If the reg that the virtual arg pointer will be translated into is
2874 not a fixed reg or is the stack pointer, make a copy of the virtual
2875 arg pointer, and address parms via the copy. The frame pointer is
2876 considered fixed even though it is not marked as such.
2878 The second time through, simply use ap to avoid generating rtx. */
2880 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
2881 || ! (fixed_regs[ARG_POINTER_REGNUM]
2882 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
2883 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
2884 else
2885 internal_arg_pointer = virtual_incoming_args_rtx;
2886 current_function_internal_arg_pointer = internal_arg_pointer;
2888 assign_parms_initialize_all (&all);
2889 fnargs = assign_parms_augmented_arg_list (&all);
2891 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
2893 struct assign_parm_data_one data;
2895 /* Extract the type of PARM; adjust it according to ABI. */
2896 assign_parm_find_data_types (&all, parm, &data);
2898 /* Early out for errors and void parameters. */
2899 if (data.passed_mode == VOIDmode)
2901 SET_DECL_RTL (parm, const0_rtx);
2902 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
2903 continue;
2906 if (current_function_stdarg && !TREE_CHAIN (parm))
2907 assign_parms_setup_varargs (&all, &data, false);
2909 /* Find out where the parameter arrives in this function. */
2910 assign_parm_find_entry_rtl (&all, &data);
2912 /* Find out where stack space for this parameter might be. */
2913 if (assign_parm_is_stack_parm (&all, &data))
2915 assign_parm_find_stack_rtl (parm, &data);
2916 assign_parm_adjust_entry_rtl (&data);
2919 /* Record permanently how this parm was passed. */
2920 set_decl_incoming_rtl (parm, data.entry_parm);
2922 /* Update info on where next arg arrives in registers. */
2923 FUNCTION_ARG_ADVANCE (all.args_so_far, data.promoted_mode,
2924 data.passed_type, data.named_arg);
2926 assign_parm_adjust_stack_rtl (&data);
2928 if (assign_parm_setup_block_p (&data))
2929 assign_parm_setup_block (&all, parm, &data);
2930 else if (data.passed_pointer || use_register_for_decl (parm))
2931 assign_parm_setup_reg (&all, parm, &data);
2932 else
2933 assign_parm_setup_stack (&all, parm, &data);
2936 if (targetm.calls.split_complex_arg && fnargs != all.orig_fnargs)
2937 assign_parms_unsplit_complex (&all, fnargs);
2939 /* Output all parameter conversion instructions (possibly including calls)
2940 now that all parameters have been copied out of hard registers. */
2941 emit_insn (all.conversion_insns);
2943 /* If we are receiving a struct value address as the first argument, set up
2944 the RTL for the function result. As this might require code to convert
2945 the transmitted address to Pmode, we do this here to ensure that possible
2946 preliminary conversions of the address have been emitted already. */
2947 if (all.function_result_decl)
2949 tree result = DECL_RESULT (current_function_decl);
2950 rtx addr = DECL_RTL (all.function_result_decl);
2951 rtx x;
2953 if (DECL_BY_REFERENCE (result))
2954 x = addr;
2955 else
2957 addr = convert_memory_address (Pmode, addr);
2958 x = gen_rtx_MEM (DECL_MODE (result), addr);
2959 set_mem_attributes (x, result, 1);
2961 SET_DECL_RTL (result, x);
2964 /* We have aligned all the args, so add space for the pretend args. */
2965 current_function_pretend_args_size = all.pretend_args_size;
2966 all.stack_args_size.constant += all.extra_pretend_bytes;
2967 current_function_args_size = all.stack_args_size.constant;
2969 /* Adjust function incoming argument size for alignment and
2970 minimum length. */
2972 #ifdef REG_PARM_STACK_SPACE
2973 current_function_args_size = MAX (current_function_args_size,
2974 REG_PARM_STACK_SPACE (fndecl));
2975 #endif
2977 current_function_args_size
2978 = ((current_function_args_size + STACK_BYTES - 1)
2979 / STACK_BYTES) * STACK_BYTES;
2981 #ifdef ARGS_GROW_DOWNWARD
2982 current_function_arg_offset_rtx
2983 = (all.stack_args_size.var == 0 ? GEN_INT (-all.stack_args_size.constant)
2984 : expand_expr (size_diffop (all.stack_args_size.var,
2985 size_int (-all.stack_args_size.constant)),
2986 NULL_RTX, VOIDmode, 0));
2987 #else
2988 current_function_arg_offset_rtx = ARGS_SIZE_RTX (all.stack_args_size);
2989 #endif
2991 /* See how many bytes, if any, of its args a function should try to pop
2992 on return. */
2994 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
2995 current_function_args_size);
2997 /* For stdarg.h function, save info about
2998 regs and stack space used by the named args. */
3000 current_function_args_info = all.args_so_far;
3002 /* Set the rtx used for the function return value. Put this in its
3003 own variable so any optimizers that need this information don't have
3004 to include tree.h. Do this here so it gets done when an inlined
3005 function gets output. */
3007 current_function_return_rtx
3008 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
3009 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
3011 /* If scalar return value was computed in a pseudo-reg, or was a named
3012 return value that got dumped to the stack, copy that to the hard
3013 return register. */
3014 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
3016 tree decl_result = DECL_RESULT (fndecl);
3017 rtx decl_rtl = DECL_RTL (decl_result);
3019 if (REG_P (decl_rtl)
3020 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
3021 : DECL_REGISTER (decl_result))
3023 rtx real_decl_rtl;
3025 #ifdef FUNCTION_OUTGOING_VALUE
3026 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
3027 fndecl);
3028 #else
3029 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
3030 fndecl);
3031 #endif
3032 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
3033 /* The delay slot scheduler assumes that current_function_return_rtx
3034 holds the hard register containing the return value, not a
3035 temporary pseudo. */
3036 current_function_return_rtx = real_decl_rtl;
3041 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3042 For all seen types, gimplify their sizes. */
3044 static tree
3045 gimplify_parm_type (tree *tp, int *walk_subtrees, void *data)
3047 tree t = *tp;
3049 *walk_subtrees = 0;
3050 if (TYPE_P (t))
3052 if (POINTER_TYPE_P (t))
3053 *walk_subtrees = 1;
3054 else if (TYPE_SIZE (t) && !TREE_CONSTANT (TYPE_SIZE (t))
3055 && !TYPE_SIZES_GIMPLIFIED (t))
3057 gimplify_type_sizes (t, (tree *) data);
3058 *walk_subtrees = 1;
3062 return NULL;
3065 /* Gimplify the parameter list for current_function_decl. This involves
3066 evaluating SAVE_EXPRs of variable sized parameters and generating code
3067 to implement callee-copies reference parameters. Returns a list of
3068 statements to add to the beginning of the function, or NULL if nothing
3069 to do. */
3071 tree
3072 gimplify_parameters (void)
3074 struct assign_parm_data_all all;
3075 tree fnargs, parm, stmts = NULL;
3077 assign_parms_initialize_all (&all);
3078 fnargs = assign_parms_augmented_arg_list (&all);
3080 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
3082 struct assign_parm_data_one data;
3084 /* Extract the type of PARM; adjust it according to ABI. */
3085 assign_parm_find_data_types (&all, parm, &data);
3087 /* Early out for errors and void parameters. */
3088 if (data.passed_mode == VOIDmode || DECL_SIZE (parm) == NULL)
3089 continue;
3091 /* Update info on where next arg arrives in registers. */
3092 FUNCTION_ARG_ADVANCE (all.args_so_far, data.promoted_mode,
3093 data.passed_type, data.named_arg);
3095 /* ??? Once upon a time variable_size stuffed parameter list
3096 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3097 turned out to be less than manageable in the gimple world.
3098 Now we have to hunt them down ourselves. */
3099 walk_tree_without_duplicates (&data.passed_type,
3100 gimplify_parm_type, &stmts);
3102 if (!TREE_CONSTANT (DECL_SIZE (parm)))
3104 gimplify_one_sizepos (&DECL_SIZE (parm), &stmts);
3105 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm), &stmts);
3108 if (data.passed_pointer)
3110 tree type = TREE_TYPE (data.passed_type);
3111 if (reference_callee_copied (&all.args_so_far, TYPE_MODE (type),
3112 type, data.named_arg))
3114 tree local, t;
3116 /* For constant sized objects, this is trivial; for
3117 variable-sized objects, we have to play games. */
3118 if (TREE_CONSTANT (DECL_SIZE (parm)))
3120 local = create_tmp_var (type, get_name (parm));
3121 DECL_IGNORED_P (local) = 0;
3123 else
3125 tree ptr_type, addr, args;
3127 ptr_type = build_pointer_type (type);
3128 addr = create_tmp_var (ptr_type, get_name (parm));
3129 DECL_IGNORED_P (addr) = 0;
3130 local = build_fold_indirect_ref (addr);
3132 args = tree_cons (NULL, DECL_SIZE_UNIT (parm), NULL);
3133 t = built_in_decls[BUILT_IN_ALLOCA];
3134 t = build_function_call_expr (t, args);
3135 t = fold_convert (ptr_type, t);
3136 t = build2 (MODIFY_EXPR, void_type_node, addr, t);
3137 gimplify_and_add (t, &stmts);
3140 t = build2 (MODIFY_EXPR, void_type_node, local, parm);
3141 gimplify_and_add (t, &stmts);
3143 DECL_VALUE_EXPR (parm) = local;
3148 return stmts;
3151 /* Indicate whether REGNO is an incoming argument to the current function
3152 that was promoted to a wider mode. If so, return the RTX for the
3153 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
3154 that REGNO is promoted from and whether the promotion was signed or
3155 unsigned. */
3158 promoted_input_arg (unsigned int regno, enum machine_mode *pmode, int *punsignedp)
3160 tree arg;
3162 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
3163 arg = TREE_CHAIN (arg))
3164 if (REG_P (DECL_INCOMING_RTL (arg))
3165 && REGNO (DECL_INCOMING_RTL (arg)) == regno
3166 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
3168 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
3169 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (arg));
3171 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
3172 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
3173 && mode != DECL_MODE (arg))
3175 *pmode = DECL_MODE (arg);
3176 *punsignedp = unsignedp;
3177 return DECL_INCOMING_RTL (arg);
3181 return 0;
3185 /* Compute the size and offset from the start of the stacked arguments for a
3186 parm passed in mode PASSED_MODE and with type TYPE.
3188 INITIAL_OFFSET_PTR points to the current offset into the stacked
3189 arguments.
3191 The starting offset and size for this parm are returned in
3192 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3193 nonzero, the offset is that of stack slot, which is returned in
3194 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3195 padding required from the initial offset ptr to the stack slot.
3197 IN_REGS is nonzero if the argument will be passed in registers. It will
3198 never be set if REG_PARM_STACK_SPACE is not defined.
3200 FNDECL is the function in which the argument was defined.
3202 There are two types of rounding that are done. The first, controlled by
3203 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
3204 list to be aligned to the specific boundary (in bits). This rounding
3205 affects the initial and starting offsets, but not the argument size.
3207 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3208 optionally rounds the size of the parm to PARM_BOUNDARY. The
3209 initial offset is not affected by this rounding, while the size always
3210 is and the starting offset may be. */
3212 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3213 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3214 callers pass in the total size of args so far as
3215 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
3217 void
3218 locate_and_pad_parm (enum machine_mode passed_mode, tree type, int in_regs,
3219 int partial, tree fndecl ATTRIBUTE_UNUSED,
3220 struct args_size *initial_offset_ptr,
3221 struct locate_and_pad_arg_data *locate)
3223 tree sizetree;
3224 enum direction where_pad;
3225 int boundary;
3226 int reg_parm_stack_space = 0;
3227 int part_size_in_regs;
3229 #ifdef REG_PARM_STACK_SPACE
3230 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
3232 /* If we have found a stack parm before we reach the end of the
3233 area reserved for registers, skip that area. */
3234 if (! in_regs)
3236 if (reg_parm_stack_space > 0)
3238 if (initial_offset_ptr->var)
3240 initial_offset_ptr->var
3241 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
3242 ssize_int (reg_parm_stack_space));
3243 initial_offset_ptr->constant = 0;
3245 else if (initial_offset_ptr->constant < reg_parm_stack_space)
3246 initial_offset_ptr->constant = reg_parm_stack_space;
3249 #endif /* REG_PARM_STACK_SPACE */
3251 part_size_in_regs = (reg_parm_stack_space == 0 ? partial : 0);
3253 sizetree
3254 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
3255 where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
3256 boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
3257 locate->where_pad = where_pad;
3258 locate->boundary = boundary;
3260 #ifdef ARGS_GROW_DOWNWARD
3261 locate->slot_offset.constant = -initial_offset_ptr->constant;
3262 if (initial_offset_ptr->var)
3263 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
3264 initial_offset_ptr->var);
3267 tree s2 = sizetree;
3268 if (where_pad != none
3269 && (!host_integerp (sizetree, 1)
3270 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
3271 s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
3272 SUB_PARM_SIZE (locate->slot_offset, s2);
3275 locate->slot_offset.constant += part_size_in_regs;
3277 if (!in_regs
3278 #ifdef REG_PARM_STACK_SPACE
3279 || REG_PARM_STACK_SPACE (fndecl) > 0
3280 #endif
3282 pad_to_arg_alignment (&locate->slot_offset, boundary,
3283 &locate->alignment_pad);
3285 locate->size.constant = (-initial_offset_ptr->constant
3286 - locate->slot_offset.constant);
3287 if (initial_offset_ptr->var)
3288 locate->size.var = size_binop (MINUS_EXPR,
3289 size_binop (MINUS_EXPR,
3290 ssize_int (0),
3291 initial_offset_ptr->var),
3292 locate->slot_offset.var);
3294 /* Pad_below needs the pre-rounded size to know how much to pad
3295 below. */
3296 locate->offset = locate->slot_offset;
3297 if (where_pad == downward)
3298 pad_below (&locate->offset, passed_mode, sizetree);
3300 #else /* !ARGS_GROW_DOWNWARD */
3301 if (!in_regs
3302 #ifdef REG_PARM_STACK_SPACE
3303 || REG_PARM_STACK_SPACE (fndecl) > 0
3304 #endif
3306 pad_to_arg_alignment (initial_offset_ptr, boundary,
3307 &locate->alignment_pad);
3308 locate->slot_offset = *initial_offset_ptr;
3310 #ifdef PUSH_ROUNDING
3311 if (passed_mode != BLKmode)
3312 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
3313 #endif
3315 /* Pad_below needs the pre-rounded size to know how much to pad below
3316 so this must be done before rounding up. */
3317 locate->offset = locate->slot_offset;
3318 if (where_pad == downward)
3319 pad_below (&locate->offset, passed_mode, sizetree);
3321 if (where_pad != none
3322 && (!host_integerp (sizetree, 1)
3323 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
3324 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
3326 ADD_PARM_SIZE (locate->size, sizetree);
3328 locate->size.constant -= part_size_in_regs;
3329 #endif /* ARGS_GROW_DOWNWARD */
3332 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
3333 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
3335 static void
3336 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
3337 struct args_size *alignment_pad)
3339 tree save_var = NULL_TREE;
3340 HOST_WIDE_INT save_constant = 0;
3341 int boundary_in_bytes = boundary / BITS_PER_UNIT;
3342 HOST_WIDE_INT sp_offset = STACK_POINTER_OFFSET;
3344 #ifdef SPARC_STACK_BOUNDARY_HACK
3345 /* The sparc port has a bug. It sometimes claims a STACK_BOUNDARY
3346 higher than the real alignment of %sp. However, when it does this,
3347 the alignment of %sp+STACK_POINTER_OFFSET will be STACK_BOUNDARY.
3348 This is a temporary hack while the sparc port is fixed. */
3349 if (SPARC_STACK_BOUNDARY_HACK)
3350 sp_offset = 0;
3351 #endif
3353 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
3355 save_var = offset_ptr->var;
3356 save_constant = offset_ptr->constant;
3359 alignment_pad->var = NULL_TREE;
3360 alignment_pad->constant = 0;
3362 if (boundary > BITS_PER_UNIT)
3364 if (offset_ptr->var)
3366 tree sp_offset_tree = ssize_int (sp_offset);
3367 tree offset = size_binop (PLUS_EXPR,
3368 ARGS_SIZE_TREE (*offset_ptr),
3369 sp_offset_tree);
3370 #ifdef ARGS_GROW_DOWNWARD
3371 tree rounded = round_down (offset, boundary / BITS_PER_UNIT);
3372 #else
3373 tree rounded = round_up (offset, boundary / BITS_PER_UNIT);
3374 #endif
3376 offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
3377 /* ARGS_SIZE_TREE includes constant term. */
3378 offset_ptr->constant = 0;
3379 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
3380 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
3381 save_var);
3383 else
3385 offset_ptr->constant = -sp_offset +
3386 #ifdef ARGS_GROW_DOWNWARD
3387 FLOOR_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
3388 #else
3389 CEIL_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
3390 #endif
3391 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
3392 alignment_pad->constant = offset_ptr->constant - save_constant;
3397 static void
3398 pad_below (struct args_size *offset_ptr, enum machine_mode passed_mode, tree sizetree)
3400 if (passed_mode != BLKmode)
3402 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
3403 offset_ptr->constant
3404 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
3405 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
3406 - GET_MODE_SIZE (passed_mode));
3408 else
3410 if (TREE_CODE (sizetree) != INTEGER_CST
3411 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
3413 /* Round the size up to multiple of PARM_BOUNDARY bits. */
3414 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
3415 /* Add it in. */
3416 ADD_PARM_SIZE (*offset_ptr, s2);
3417 SUB_PARM_SIZE (*offset_ptr, sizetree);
3422 /* Walk the tree of blocks describing the binding levels within a function
3423 and warn about variables the might be killed by setjmp or vfork.
3424 This is done after calling flow_analysis and before global_alloc
3425 clobbers the pseudo-regs to hard regs. */
3427 void
3428 setjmp_vars_warning (tree block)
3430 tree decl, sub;
3432 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
3434 if (TREE_CODE (decl) == VAR_DECL
3435 && DECL_RTL_SET_P (decl)
3436 && REG_P (DECL_RTL (decl))
3437 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
3438 warning (0, "%Jvariable %qD might be clobbered by %<longjmp%>"
3439 " or %<vfork%>",
3440 decl, decl);
3443 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
3444 setjmp_vars_warning (sub);
3447 /* Do the appropriate part of setjmp_vars_warning
3448 but for arguments instead of local variables. */
3450 void
3451 setjmp_args_warning (void)
3453 tree decl;
3454 for (decl = DECL_ARGUMENTS (current_function_decl);
3455 decl; decl = TREE_CHAIN (decl))
3456 if (DECL_RTL (decl) != 0
3457 && REG_P (DECL_RTL (decl))
3458 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
3459 warning (0, "%Jargument %qD might be clobbered by %<longjmp%> or %<vfork%>",
3460 decl, decl);
3464 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
3465 and create duplicate blocks. */
3466 /* ??? Need an option to either create block fragments or to create
3467 abstract origin duplicates of a source block. It really depends
3468 on what optimization has been performed. */
3470 void
3471 reorder_blocks (void)
3473 tree block = DECL_INITIAL (current_function_decl);
3474 VEC(tree,heap) *block_stack;
3476 if (block == NULL_TREE)
3477 return;
3479 block_stack = VEC_alloc (tree, heap, 10);
3481 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
3482 clear_block_marks (block);
3484 /* Prune the old trees away, so that they don't get in the way. */
3485 BLOCK_SUBBLOCKS (block) = NULL_TREE;
3486 BLOCK_CHAIN (block) = NULL_TREE;
3488 /* Recreate the block tree from the note nesting. */
3489 reorder_blocks_1 (get_insns (), block, &block_stack);
3490 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
3492 /* Remove deleted blocks from the block fragment chains. */
3493 reorder_fix_fragments (block);
3495 VEC_free (tree, heap, block_stack);
3498 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
3500 void
3501 clear_block_marks (tree block)
3503 while (block)
3505 TREE_ASM_WRITTEN (block) = 0;
3506 clear_block_marks (BLOCK_SUBBLOCKS (block));
3507 block = BLOCK_CHAIN (block);
3511 static void
3512 reorder_blocks_1 (rtx insns, tree current_block, VEC(tree,heap) **p_block_stack)
3514 rtx insn;
3516 for (insn = insns; insn; insn = NEXT_INSN (insn))
3518 if (NOTE_P (insn))
3520 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
3522 tree block = NOTE_BLOCK (insn);
3524 /* If we have seen this block before, that means it now
3525 spans multiple address regions. Create a new fragment. */
3526 if (TREE_ASM_WRITTEN (block))
3528 tree new_block = copy_node (block);
3529 tree origin;
3531 origin = (BLOCK_FRAGMENT_ORIGIN (block)
3532 ? BLOCK_FRAGMENT_ORIGIN (block)
3533 : block);
3534 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
3535 BLOCK_FRAGMENT_CHAIN (new_block)
3536 = BLOCK_FRAGMENT_CHAIN (origin);
3537 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
3539 NOTE_BLOCK (insn) = new_block;
3540 block = new_block;
3543 BLOCK_SUBBLOCKS (block) = 0;
3544 TREE_ASM_WRITTEN (block) = 1;
3545 /* When there's only one block for the entire function,
3546 current_block == block and we mustn't do this, it
3547 will cause infinite recursion. */
3548 if (block != current_block)
3550 BLOCK_SUPERCONTEXT (block) = current_block;
3551 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
3552 BLOCK_SUBBLOCKS (current_block) = block;
3553 current_block = block;
3555 VEC_safe_push (tree, heap, *p_block_stack, block);
3557 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
3559 NOTE_BLOCK (insn) = VEC_pop (tree, *p_block_stack);
3560 BLOCK_SUBBLOCKS (current_block)
3561 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
3562 current_block = BLOCK_SUPERCONTEXT (current_block);
3568 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
3569 appears in the block tree, select one of the fragments to become
3570 the new origin block. */
3572 static void
3573 reorder_fix_fragments (tree block)
3575 while (block)
3577 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
3578 tree new_origin = NULL_TREE;
3580 if (dup_origin)
3582 if (! TREE_ASM_WRITTEN (dup_origin))
3584 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
3586 /* Find the first of the remaining fragments. There must
3587 be at least one -- the current block. */
3588 while (! TREE_ASM_WRITTEN (new_origin))
3589 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
3590 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
3593 else if (! dup_origin)
3594 new_origin = block;
3596 /* Re-root the rest of the fragments to the new origin. In the
3597 case that DUP_ORIGIN was null, that means BLOCK was the origin
3598 of a chain of fragments and we want to remove those fragments
3599 that didn't make it to the output. */
3600 if (new_origin)
3602 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
3603 tree chain = *pp;
3605 while (chain)
3607 if (TREE_ASM_WRITTEN (chain))
3609 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
3610 *pp = chain;
3611 pp = &BLOCK_FRAGMENT_CHAIN (chain);
3613 chain = BLOCK_FRAGMENT_CHAIN (chain);
3615 *pp = NULL_TREE;
3618 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
3619 block = BLOCK_CHAIN (block);
3623 /* Reverse the order of elements in the chain T of blocks,
3624 and return the new head of the chain (old last element). */
3626 tree
3627 blocks_nreverse (tree t)
3629 tree prev = 0, decl, next;
3630 for (decl = t; decl; decl = next)
3632 next = BLOCK_CHAIN (decl);
3633 BLOCK_CHAIN (decl) = prev;
3634 prev = decl;
3636 return prev;
3639 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
3640 non-NULL, list them all into VECTOR, in a depth-first preorder
3641 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
3642 blocks. */
3644 static int
3645 all_blocks (tree block, tree *vector)
3647 int n_blocks = 0;
3649 while (block)
3651 TREE_ASM_WRITTEN (block) = 0;
3653 /* Record this block. */
3654 if (vector)
3655 vector[n_blocks] = block;
3657 ++n_blocks;
3659 /* Record the subblocks, and their subblocks... */
3660 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
3661 vector ? vector + n_blocks : 0);
3662 block = BLOCK_CHAIN (block);
3665 return n_blocks;
3668 /* Return a vector containing all the blocks rooted at BLOCK. The
3669 number of elements in the vector is stored in N_BLOCKS_P. The
3670 vector is dynamically allocated; it is the caller's responsibility
3671 to call `free' on the pointer returned. */
3673 static tree *
3674 get_block_vector (tree block, int *n_blocks_p)
3676 tree *block_vector;
3678 *n_blocks_p = all_blocks (block, NULL);
3679 block_vector = xmalloc (*n_blocks_p * sizeof (tree));
3680 all_blocks (block, block_vector);
3682 return block_vector;
3685 static GTY(()) int next_block_index = 2;
3687 /* Set BLOCK_NUMBER for all the blocks in FN. */
3689 void
3690 number_blocks (tree fn)
3692 int i;
3693 int n_blocks;
3694 tree *block_vector;
3696 /* For SDB and XCOFF debugging output, we start numbering the blocks
3697 from 1 within each function, rather than keeping a running
3698 count. */
3699 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
3700 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
3701 next_block_index = 1;
3702 #endif
3704 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
3706 /* The top-level BLOCK isn't numbered at all. */
3707 for (i = 1; i < n_blocks; ++i)
3708 /* We number the blocks from two. */
3709 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
3711 free (block_vector);
3713 return;
3716 /* If VAR is present in a subblock of BLOCK, return the subblock. */
3718 tree
3719 debug_find_var_in_block_tree (tree var, tree block)
3721 tree t;
3723 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
3724 if (t == var)
3725 return block;
3727 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
3729 tree ret = debug_find_var_in_block_tree (var, t);
3730 if (ret)
3731 return ret;
3734 return NULL_TREE;
3737 /* Allocate a function structure for FNDECL and set its contents
3738 to the defaults. */
3740 void
3741 allocate_struct_function (tree fndecl)
3743 tree result;
3744 tree fntype = fndecl ? TREE_TYPE (fndecl) : NULL_TREE;
3746 cfun = ggc_alloc_cleared (sizeof (struct function));
3748 cfun->stack_alignment_needed = STACK_BOUNDARY;
3749 cfun->preferred_stack_boundary = STACK_BOUNDARY;
3751 current_function_funcdef_no = funcdef_no++;
3753 cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL;
3755 init_eh_for_function ();
3757 lang_hooks.function.init (cfun);
3758 if (init_machine_status)
3759 cfun->machine = (*init_machine_status) ();
3761 if (fndecl == NULL)
3762 return;
3764 DECL_STRUCT_FUNCTION (fndecl) = cfun;
3765 cfun->decl = fndecl;
3767 result = DECL_RESULT (fndecl);
3768 if (aggregate_value_p (result, fndecl))
3770 #ifdef PCC_STATIC_STRUCT_RETURN
3771 current_function_returns_pcc_struct = 1;
3772 #endif
3773 current_function_returns_struct = 1;
3776 current_function_returns_pointer = POINTER_TYPE_P (TREE_TYPE (result));
3778 current_function_stdarg
3779 = (fntype
3780 && TYPE_ARG_TYPES (fntype) != 0
3781 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
3782 != void_type_node));
3784 /* Assume all registers in stdarg functions need to be saved. */
3785 cfun->va_list_gpr_size = VA_LIST_MAX_GPR_SIZE;
3786 cfun->va_list_fpr_size = VA_LIST_MAX_FPR_SIZE;
3789 /* Reset cfun, and other non-struct-function variables to defaults as
3790 appropriate for emitting rtl at the start of a function. */
3792 static void
3793 prepare_function_start (tree fndecl)
3795 if (fndecl && DECL_STRUCT_FUNCTION (fndecl))
3796 cfun = DECL_STRUCT_FUNCTION (fndecl);
3797 else
3798 allocate_struct_function (fndecl);
3799 init_emit ();
3800 init_varasm_status (cfun);
3801 init_expr ();
3803 cse_not_expected = ! optimize;
3805 /* Caller save not needed yet. */
3806 caller_save_needed = 0;
3808 /* We haven't done register allocation yet. */
3809 reg_renumber = 0;
3811 /* Indicate that we have not instantiated virtual registers yet. */
3812 virtuals_instantiated = 0;
3814 /* Indicate that we want CONCATs now. */
3815 generating_concat_p = 1;
3817 /* Indicate we have no need of a frame pointer yet. */
3818 frame_pointer_needed = 0;
3821 /* Initialize the rtl expansion mechanism so that we can do simple things
3822 like generate sequences. This is used to provide a context during global
3823 initialization of some passes. */
3824 void
3825 init_dummy_function_start (void)
3827 prepare_function_start (NULL);
3830 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
3831 and initialize static variables for generating RTL for the statements
3832 of the function. */
3834 void
3835 init_function_start (tree subr)
3837 prepare_function_start (subr);
3839 /* Prevent ever trying to delete the first instruction of a
3840 function. Also tell final how to output a linenum before the
3841 function prologue. Note linenums could be missing, e.g. when
3842 compiling a Java .class file. */
3843 if (! DECL_IS_BUILTIN (subr))
3844 emit_line_note (DECL_SOURCE_LOCATION (subr));
3846 /* Make sure first insn is a note even if we don't want linenums.
3847 This makes sure the first insn will never be deleted.
3848 Also, final expects a note to appear there. */
3849 emit_note (NOTE_INSN_DELETED);
3851 /* Warn if this value is an aggregate type,
3852 regardless of which calling convention we are using for it. */
3853 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
3854 warning (OPT_Waggregate_return, "function returns an aggregate");
3857 /* Make sure all values used by the optimization passes have sane
3858 defaults. */
3859 void
3860 init_function_for_compilation (void)
3862 reg_renumber = 0;
3864 /* No prologue/epilogue insns yet. */
3865 VARRAY_GROW (prologue, 0);
3866 VARRAY_GROW (epilogue, 0);
3867 VARRAY_GROW (sibcall_epilogue, 0);
3870 void
3871 expand_main_function (void)
3873 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
3874 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
3876 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
3877 rtx tmp, seq;
3879 start_sequence ();
3880 /* Forcibly align the stack. */
3881 #ifdef STACK_GROWS_DOWNWARD
3882 tmp = expand_simple_binop (Pmode, AND, stack_pointer_rtx, GEN_INT(-align),
3883 stack_pointer_rtx, 1, OPTAB_WIDEN);
3884 #else
3885 tmp = expand_simple_binop (Pmode, PLUS, stack_pointer_rtx,
3886 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
3887 tmp = expand_simple_binop (Pmode, AND, tmp, GEN_INT (-align),
3888 stack_pointer_rtx, 1, OPTAB_WIDEN);
3889 #endif
3890 if (tmp != stack_pointer_rtx)
3891 emit_move_insn (stack_pointer_rtx, tmp);
3893 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
3894 tmp = force_reg (Pmode, const0_rtx);
3895 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
3896 seq = get_insns ();
3897 end_sequence ();
3899 for (tmp = get_last_insn (); tmp; tmp = PREV_INSN (tmp))
3900 if (NOTE_P (tmp) && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_FUNCTION_BEG)
3901 break;
3902 if (tmp)
3903 emit_insn_before (seq, tmp);
3904 else
3905 emit_insn (seq);
3907 #endif
3909 #if (defined(INVOKE__main) \
3910 || (!defined(HAS_INIT_SECTION) \
3911 && !defined(INIT_SECTION_ASM_OP) \
3912 && !defined(INIT_ARRAY_SECTION_ASM_OP)))
3913 emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0);
3914 #endif
3917 /* Start the RTL for a new function, and set variables used for
3918 emitting RTL.
3919 SUBR is the FUNCTION_DECL node.
3920 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
3921 the function's parameters, which must be run at any return statement. */
3923 void
3924 expand_function_start (tree subr)
3926 /* Make sure volatile mem refs aren't considered
3927 valid operands of arithmetic insns. */
3928 init_recog_no_volatile ();
3930 current_function_profile
3931 = (profile_flag
3932 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
3934 current_function_limit_stack
3935 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
3937 /* Make the label for return statements to jump to. Do not special
3938 case machines with special return instructions -- they will be
3939 handled later during jump, ifcvt, or epilogue creation. */
3940 return_label = gen_label_rtx ();
3942 /* Initialize rtx used to return the value. */
3943 /* Do this before assign_parms so that we copy the struct value address
3944 before any library calls that assign parms might generate. */
3946 /* Decide whether to return the value in memory or in a register. */
3947 if (aggregate_value_p (DECL_RESULT (subr), subr))
3949 /* Returning something that won't go in a register. */
3950 rtx value_address = 0;
3952 #ifdef PCC_STATIC_STRUCT_RETURN
3953 if (current_function_returns_pcc_struct)
3955 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
3956 value_address = assemble_static_space (size);
3958 else
3959 #endif
3961 rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 1);
3962 /* Expect to be passed the address of a place to store the value.
3963 If it is passed as an argument, assign_parms will take care of
3964 it. */
3965 if (sv)
3967 value_address = gen_reg_rtx (Pmode);
3968 emit_move_insn (value_address, sv);
3971 if (value_address)
3973 rtx x = value_address;
3974 if (!DECL_BY_REFERENCE (DECL_RESULT (subr)))
3976 x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), x);
3977 set_mem_attributes (x, DECL_RESULT (subr), 1);
3979 SET_DECL_RTL (DECL_RESULT (subr), x);
3982 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
3983 /* If return mode is void, this decl rtl should not be used. */
3984 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
3985 else
3987 /* Compute the return values into a pseudo reg, which we will copy
3988 into the true return register after the cleanups are done. */
3989 tree return_type = TREE_TYPE (DECL_RESULT (subr));
3990 if (TYPE_MODE (return_type) != BLKmode
3991 && targetm.calls.return_in_msb (return_type))
3992 /* expand_function_end will insert the appropriate padding in
3993 this case. Use the return value's natural (unpadded) mode
3994 within the function proper. */
3995 SET_DECL_RTL (DECL_RESULT (subr),
3996 gen_reg_rtx (TYPE_MODE (return_type)));
3997 else
3999 /* In order to figure out what mode to use for the pseudo, we
4000 figure out what the mode of the eventual return register will
4001 actually be, and use that. */
4002 rtx hard_reg = hard_function_value (return_type, subr, 1);
4004 /* Structures that are returned in registers are not
4005 aggregate_value_p, so we may see a PARALLEL or a REG. */
4006 if (REG_P (hard_reg))
4007 SET_DECL_RTL (DECL_RESULT (subr),
4008 gen_reg_rtx (GET_MODE (hard_reg)));
4009 else
4011 gcc_assert (GET_CODE (hard_reg) == PARALLEL);
4012 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
4016 /* Set DECL_REGISTER flag so that expand_function_end will copy the
4017 result to the real return register(s). */
4018 DECL_REGISTER (DECL_RESULT (subr)) = 1;
4021 /* Initialize rtx for parameters and local variables.
4022 In some cases this requires emitting insns. */
4023 assign_parms (subr);
4025 /* If function gets a static chain arg, store it. */
4026 if (cfun->static_chain_decl)
4028 tree parm = cfun->static_chain_decl;
4029 rtx local = gen_reg_rtx (Pmode);
4031 set_decl_incoming_rtl (parm, static_chain_incoming_rtx);
4032 SET_DECL_RTL (parm, local);
4033 mark_reg_pointer (local, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
4035 emit_move_insn (local, static_chain_incoming_rtx);
4038 /* If the function receives a non-local goto, then store the
4039 bits we need to restore the frame pointer. */
4040 if (cfun->nonlocal_goto_save_area)
4042 tree t_save;
4043 rtx r_save;
4045 /* ??? We need to do this save early. Unfortunately here is
4046 before the frame variable gets declared. Help out... */
4047 expand_var (TREE_OPERAND (cfun->nonlocal_goto_save_area, 0));
4049 t_save = build4 (ARRAY_REF, ptr_type_node,
4050 cfun->nonlocal_goto_save_area,
4051 integer_zero_node, NULL_TREE, NULL_TREE);
4052 r_save = expand_expr (t_save, NULL_RTX, VOIDmode, EXPAND_WRITE);
4053 r_save = convert_memory_address (Pmode, r_save);
4055 emit_move_insn (r_save, virtual_stack_vars_rtx);
4056 update_nonlocal_goto_save_area ();
4059 /* The following was moved from init_function_start.
4060 The move is supposed to make sdb output more accurate. */
4061 /* Indicate the beginning of the function body,
4062 as opposed to parm setup. */
4063 emit_note (NOTE_INSN_FUNCTION_BEG);
4065 if (!NOTE_P (get_last_insn ()))
4066 emit_note (NOTE_INSN_DELETED);
4067 parm_birth_insn = get_last_insn ();
4069 if (current_function_profile)
4071 #ifdef PROFILE_HOOK
4072 PROFILE_HOOK (current_function_funcdef_no);
4073 #endif
4076 /* After the display initializations is where the tail-recursion label
4077 should go, if we end up needing one. Ensure we have a NOTE here
4078 since some things (like trampolines) get placed before this. */
4079 tail_recursion_reentry = emit_note (NOTE_INSN_DELETED);
4081 /* Make sure there is a line number after the function entry setup code. */
4082 force_next_line_note ();
4085 /* Undo the effects of init_dummy_function_start. */
4086 void
4087 expand_dummy_function_end (void)
4089 /* End any sequences that failed to be closed due to syntax errors. */
4090 while (in_sequence_p ())
4091 end_sequence ();
4093 /* Outside function body, can't compute type's actual size
4094 until next function's body starts. */
4096 free_after_parsing (cfun);
4097 free_after_compilation (cfun);
4098 cfun = 0;
4101 /* Call DOIT for each hard register used as a return value from
4102 the current function. */
4104 void
4105 diddle_return_value (void (*doit) (rtx, void *), void *arg)
4107 rtx outgoing = current_function_return_rtx;
4109 if (! outgoing)
4110 return;
4112 if (REG_P (outgoing))
4113 (*doit) (outgoing, arg);
4114 else if (GET_CODE (outgoing) == PARALLEL)
4116 int i;
4118 for (i = 0; i < XVECLEN (outgoing, 0); i++)
4120 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
4122 if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER)
4123 (*doit) (x, arg);
4128 static void
4129 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
4131 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
4134 void
4135 clobber_return_register (void)
4137 diddle_return_value (do_clobber_return_reg, NULL);
4139 /* In case we do use pseudo to return value, clobber it too. */
4140 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
4142 tree decl_result = DECL_RESULT (current_function_decl);
4143 rtx decl_rtl = DECL_RTL (decl_result);
4144 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
4146 do_clobber_return_reg (decl_rtl, NULL);
4151 static void
4152 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
4154 emit_insn (gen_rtx_USE (VOIDmode, reg));
4157 void
4158 use_return_register (void)
4160 diddle_return_value (do_use_return_reg, NULL);
4163 /* Possibly warn about unused parameters. */
4164 void
4165 do_warn_unused_parameter (tree fn)
4167 tree decl;
4169 for (decl = DECL_ARGUMENTS (fn);
4170 decl; decl = TREE_CHAIN (decl))
4171 if (!TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
4172 && DECL_NAME (decl) && !DECL_ARTIFICIAL (decl))
4173 warning (0, "%Junused parameter %qD", decl, decl);
4176 static GTY(()) rtx initial_trampoline;
4178 /* Generate RTL for the end of the current function. */
4180 void
4181 expand_function_end (void)
4183 rtx clobber_after;
4185 /* If arg_pointer_save_area was referenced only from a nested
4186 function, we will not have initialized it yet. Do that now. */
4187 if (arg_pointer_save_area && ! cfun->arg_pointer_save_area_init)
4188 get_arg_pointer_save_area (cfun);
4190 /* If we are doing stack checking and this function makes calls,
4191 do a stack probe at the start of the function to ensure we have enough
4192 space for another stack frame. */
4193 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
4195 rtx insn, seq;
4197 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4198 if (CALL_P (insn))
4200 start_sequence ();
4201 probe_stack_range (STACK_CHECK_PROTECT,
4202 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
4203 seq = get_insns ();
4204 end_sequence ();
4205 emit_insn_before (seq, tail_recursion_reentry);
4206 break;
4210 /* Possibly warn about unused parameters.
4211 When frontend does unit-at-a-time, the warning is already
4212 issued at finalization time. */
4213 if (warn_unused_parameter
4214 && !lang_hooks.callgraph.expand_function)
4215 do_warn_unused_parameter (current_function_decl);
4217 /* End any sequences that failed to be closed due to syntax errors. */
4218 while (in_sequence_p ())
4219 end_sequence ();
4221 clear_pending_stack_adjust ();
4222 do_pending_stack_adjust ();
4224 /* @@@ This is a kludge. We want to ensure that instructions that
4225 may trap are not moved into the epilogue by scheduling, because
4226 we don't always emit unwind information for the epilogue.
4227 However, not all machine descriptions define a blockage insn, so
4228 emit an ASM_INPUT to act as one. */
4229 if (flag_non_call_exceptions)
4230 emit_insn (gen_rtx_ASM_INPUT (VOIDmode, ""));
4232 /* Mark the end of the function body.
4233 If control reaches this insn, the function can drop through
4234 without returning a value. */
4235 emit_note (NOTE_INSN_FUNCTION_END);
4237 /* Must mark the last line number note in the function, so that the test
4238 coverage code can avoid counting the last line twice. This just tells
4239 the code to ignore the immediately following line note, since there
4240 already exists a copy of this note somewhere above. This line number
4241 note is still needed for debugging though, so we can't delete it. */
4242 if (flag_test_coverage)
4243 emit_note (NOTE_INSN_REPEATED_LINE_NUMBER);
4245 /* Output a linenumber for the end of the function.
4246 SDB depends on this. */
4247 force_next_line_note ();
4248 emit_line_note (input_location);
4250 /* Before the return label (if any), clobber the return
4251 registers so that they are not propagated live to the rest of
4252 the function. This can only happen with functions that drop
4253 through; if there had been a return statement, there would
4254 have either been a return rtx, or a jump to the return label.
4256 We delay actual code generation after the current_function_value_rtx
4257 is computed. */
4258 clobber_after = get_last_insn ();
4260 /* Output the label for the actual return from the function. */
4261 emit_label (return_label);
4263 /* Let except.c know where it should emit the call to unregister
4264 the function context for sjlj exceptions. */
4265 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
4266 sjlj_emit_function_exit_after (get_last_insn ());
4268 /* If scalar return value was computed in a pseudo-reg, or was a named
4269 return value that got dumped to the stack, copy that to the hard
4270 return register. */
4271 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
4273 tree decl_result = DECL_RESULT (current_function_decl);
4274 rtx decl_rtl = DECL_RTL (decl_result);
4276 if (REG_P (decl_rtl)
4277 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
4278 : DECL_REGISTER (decl_result))
4280 rtx real_decl_rtl = current_function_return_rtx;
4282 /* This should be set in assign_parms. */
4283 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl));
4285 /* If this is a BLKmode structure being returned in registers,
4286 then use the mode computed in expand_return. Note that if
4287 decl_rtl is memory, then its mode may have been changed,
4288 but that current_function_return_rtx has not. */
4289 if (GET_MODE (real_decl_rtl) == BLKmode)
4290 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
4292 /* If a non-BLKmode return value should be padded at the least
4293 significant end of the register, shift it left by the appropriate
4294 amount. BLKmode results are handled using the group load/store
4295 machinery. */
4296 if (TYPE_MODE (TREE_TYPE (decl_result)) != BLKmode
4297 && targetm.calls.return_in_msb (TREE_TYPE (decl_result)))
4299 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl),
4300 REGNO (real_decl_rtl)),
4301 decl_rtl);
4302 shift_return_value (GET_MODE (decl_rtl), true, real_decl_rtl);
4304 /* If a named return value dumped decl_return to memory, then
4305 we may need to re-do the PROMOTE_MODE signed/unsigned
4306 extension. */
4307 else if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
4309 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (decl_result));
4311 if (targetm.calls.promote_function_return (TREE_TYPE (current_function_decl)))
4312 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
4313 &unsignedp, 1);
4315 convert_move (real_decl_rtl, decl_rtl, unsignedp);
4317 else if (GET_CODE (real_decl_rtl) == PARALLEL)
4319 /* If expand_function_start has created a PARALLEL for decl_rtl,
4320 move the result to the real return registers. Otherwise, do
4321 a group load from decl_rtl for a named return. */
4322 if (GET_CODE (decl_rtl) == PARALLEL)
4323 emit_group_move (real_decl_rtl, decl_rtl);
4324 else
4325 emit_group_load (real_decl_rtl, decl_rtl,
4326 TREE_TYPE (decl_result),
4327 int_size_in_bytes (TREE_TYPE (decl_result)));
4329 else
4330 emit_move_insn (real_decl_rtl, decl_rtl);
4334 /* If returning a structure, arrange to return the address of the value
4335 in a place where debuggers expect to find it.
4337 If returning a structure PCC style,
4338 the caller also depends on this value.
4339 And current_function_returns_pcc_struct is not necessarily set. */
4340 if (current_function_returns_struct
4341 || current_function_returns_pcc_struct)
4343 rtx value_address = DECL_RTL (DECL_RESULT (current_function_decl));
4344 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
4345 rtx outgoing;
4347 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))
4348 type = TREE_TYPE (type);
4349 else
4350 value_address = XEXP (value_address, 0);
4352 #ifdef FUNCTION_OUTGOING_VALUE
4353 outgoing = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
4354 current_function_decl);
4355 #else
4356 outgoing = FUNCTION_VALUE (build_pointer_type (type),
4357 current_function_decl);
4358 #endif
4360 /* Mark this as a function return value so integrate will delete the
4361 assignment and USE below when inlining this function. */
4362 REG_FUNCTION_VALUE_P (outgoing) = 1;
4364 /* The address may be ptr_mode and OUTGOING may be Pmode. */
4365 value_address = convert_memory_address (GET_MODE (outgoing),
4366 value_address);
4368 emit_move_insn (outgoing, value_address);
4370 /* Show return register used to hold result (in this case the address
4371 of the result. */
4372 current_function_return_rtx = outgoing;
4375 /* If this is an implementation of throw, do what's necessary to
4376 communicate between __builtin_eh_return and the epilogue. */
4377 expand_eh_return ();
4379 /* Emit the actual code to clobber return register. */
4381 rtx seq;
4383 start_sequence ();
4384 clobber_return_register ();
4385 expand_naked_return ();
4386 seq = get_insns ();
4387 end_sequence ();
4389 emit_insn_after (seq, clobber_after);
4392 /* Output the label for the naked return from the function. */
4393 emit_label (naked_return_label);
4395 /* If we had calls to alloca, and this machine needs
4396 an accurate stack pointer to exit the function,
4397 insert some code to save and restore the stack pointer. */
4398 if (! EXIT_IGNORE_STACK
4399 && current_function_calls_alloca)
4401 rtx tem = 0;
4403 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
4404 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
4407 /* ??? This should no longer be necessary since stupid is no longer with
4408 us, but there are some parts of the compiler (eg reload_combine, and
4409 sh mach_dep_reorg) that still try and compute their own lifetime info
4410 instead of using the general framework. */
4411 use_return_register ();
4415 get_arg_pointer_save_area (struct function *f)
4417 rtx ret = f->x_arg_pointer_save_area;
4419 if (! ret)
4421 ret = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, f);
4422 f->x_arg_pointer_save_area = ret;
4425 if (f == cfun && ! f->arg_pointer_save_area_init)
4427 rtx seq;
4429 /* Save the arg pointer at the beginning of the function. The
4430 generated stack slot may not be a valid memory address, so we
4431 have to check it and fix it if necessary. */
4432 start_sequence ();
4433 emit_move_insn (validize_mem (ret), virtual_incoming_args_rtx);
4434 seq = get_insns ();
4435 end_sequence ();
4437 push_topmost_sequence ();
4438 emit_insn_after (seq, entry_of_function ());
4439 pop_topmost_sequence ();
4442 return ret;
4445 /* Extend a vector that records the INSN_UIDs of INSNS
4446 (a list of one or more insns). */
4448 static void
4449 record_insns (rtx insns, varray_type *vecp)
4451 int i, len;
4452 rtx tmp;
4454 tmp = insns;
4455 len = 0;
4456 while (tmp != NULL_RTX)
4458 len++;
4459 tmp = NEXT_INSN (tmp);
4462 i = VARRAY_SIZE (*vecp);
4463 VARRAY_GROW (*vecp, i + len);
4464 tmp = insns;
4465 while (tmp != NULL_RTX)
4467 VARRAY_INT (*vecp, i) = INSN_UID (tmp);
4468 i++;
4469 tmp = NEXT_INSN (tmp);
4473 /* Set the locator of the insn chain starting at INSN to LOC. */
4474 static void
4475 set_insn_locators (rtx insn, int loc)
4477 while (insn != NULL_RTX)
4479 if (INSN_P (insn))
4480 INSN_LOCATOR (insn) = loc;
4481 insn = NEXT_INSN (insn);
4485 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
4486 be running after reorg, SEQUENCE rtl is possible. */
4488 static int
4489 contains (rtx insn, varray_type vec)
4491 int i, j;
4493 if (NONJUMP_INSN_P (insn)
4494 && GET_CODE (PATTERN (insn)) == SEQUENCE)
4496 int count = 0;
4497 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
4498 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
4499 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
4500 count++;
4501 return count;
4503 else
4505 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
4506 if (INSN_UID (insn) == VARRAY_INT (vec, j))
4507 return 1;
4509 return 0;
4513 prologue_epilogue_contains (rtx insn)
4515 if (contains (insn, prologue))
4516 return 1;
4517 if (contains (insn, epilogue))
4518 return 1;
4519 return 0;
4523 sibcall_epilogue_contains (rtx insn)
4525 if (sibcall_epilogue)
4526 return contains (insn, sibcall_epilogue);
4527 return 0;
4530 #ifdef HAVE_return
4531 /* Insert gen_return at the end of block BB. This also means updating
4532 block_for_insn appropriately. */
4534 static void
4535 emit_return_into_block (basic_block bb, rtx line_note)
4537 emit_jump_insn_after (gen_return (), BB_END (bb));
4538 if (line_note)
4539 emit_note_copy_after (line_note, PREV_INSN (BB_END (bb)));
4541 #endif /* HAVE_return */
4543 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
4545 /* These functions convert the epilogue into a variant that does not
4546 modify the stack pointer. This is used in cases where a function
4547 returns an object whose size is not known until it is computed.
4548 The called function leaves the object on the stack, leaves the
4549 stack depressed, and returns a pointer to the object.
4551 What we need to do is track all modifications and references to the
4552 stack pointer, deleting the modifications and changing the
4553 references to point to the location the stack pointer would have
4554 pointed to had the modifications taken place.
4556 These functions need to be portable so we need to make as few
4557 assumptions about the epilogue as we can. However, the epilogue
4558 basically contains three things: instructions to reset the stack
4559 pointer, instructions to reload registers, possibly including the
4560 frame pointer, and an instruction to return to the caller.
4562 We must be sure of what a relevant epilogue insn is doing. We also
4563 make no attempt to validate the insns we make since if they are
4564 invalid, we probably can't do anything valid. The intent is that
4565 these routines get "smarter" as more and more machines start to use
4566 them and they try operating on different epilogues.
4568 We use the following structure to track what the part of the
4569 epilogue that we've already processed has done. We keep two copies
4570 of the SP equivalence, one for use during the insn we are
4571 processing and one for use in the next insn. The difference is
4572 because one part of a PARALLEL may adjust SP and the other may use
4573 it. */
4575 struct epi_info
4577 rtx sp_equiv_reg; /* REG that SP is set from, perhaps SP. */
4578 HOST_WIDE_INT sp_offset; /* Offset from SP_EQUIV_REG of present SP. */
4579 rtx new_sp_equiv_reg; /* REG to be used at end of insn. */
4580 HOST_WIDE_INT new_sp_offset; /* Offset to be used at end of insn. */
4581 rtx equiv_reg_src; /* If nonzero, the value that SP_EQUIV_REG
4582 should be set to once we no longer need
4583 its value. */
4584 rtx const_equiv[FIRST_PSEUDO_REGISTER]; /* Any known constant equivalences
4585 for registers. */
4588 static void handle_epilogue_set (rtx, struct epi_info *);
4589 static void update_epilogue_consts (rtx, rtx, void *);
4590 static void emit_equiv_load (struct epi_info *);
4592 /* Modify INSN, a list of one or more insns that is part of the epilogue, to
4593 no modifications to the stack pointer. Return the new list of insns. */
4595 static rtx
4596 keep_stack_depressed (rtx insns)
4598 int j;
4599 struct epi_info info;
4600 rtx insn, next;
4602 /* If the epilogue is just a single instruction, it must be OK as is. */
4603 if (NEXT_INSN (insns) == NULL_RTX)
4604 return insns;
4606 /* Otherwise, start a sequence, initialize the information we have, and
4607 process all the insns we were given. */
4608 start_sequence ();
4610 info.sp_equiv_reg = stack_pointer_rtx;
4611 info.sp_offset = 0;
4612 info.equiv_reg_src = 0;
4614 for (j = 0; j < FIRST_PSEUDO_REGISTER; j++)
4615 info.const_equiv[j] = 0;
4617 insn = insns;
4618 next = NULL_RTX;
4619 while (insn != NULL_RTX)
4621 next = NEXT_INSN (insn);
4623 if (!INSN_P (insn))
4625 add_insn (insn);
4626 insn = next;
4627 continue;
4630 /* If this insn references the register that SP is equivalent to and
4631 we have a pending load to that register, we must force out the load
4632 first and then indicate we no longer know what SP's equivalent is. */
4633 if (info.equiv_reg_src != 0
4634 && reg_referenced_p (info.sp_equiv_reg, PATTERN (insn)))
4636 emit_equiv_load (&info);
4637 info.sp_equiv_reg = 0;
4640 info.new_sp_equiv_reg = info.sp_equiv_reg;
4641 info.new_sp_offset = info.sp_offset;
4643 /* If this is a (RETURN) and the return address is on the stack,
4644 update the address and change to an indirect jump. */
4645 if (GET_CODE (PATTERN (insn)) == RETURN
4646 || (GET_CODE (PATTERN (insn)) == PARALLEL
4647 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == RETURN))
4649 rtx retaddr = INCOMING_RETURN_ADDR_RTX;
4650 rtx base = 0;
4651 HOST_WIDE_INT offset = 0;
4652 rtx jump_insn, jump_set;
4654 /* If the return address is in a register, we can emit the insn
4655 unchanged. Otherwise, it must be a MEM and we see what the
4656 base register and offset are. In any case, we have to emit any
4657 pending load to the equivalent reg of SP, if any. */
4658 if (REG_P (retaddr))
4660 emit_equiv_load (&info);
4661 add_insn (insn);
4662 insn = next;
4663 continue;
4665 else
4667 rtx ret_ptr;
4668 gcc_assert (MEM_P (retaddr));
4670 ret_ptr = XEXP (retaddr, 0);
4672 if (REG_P (ret_ptr))
4674 base = gen_rtx_REG (Pmode, REGNO (ret_ptr));
4675 offset = 0;
4677 else
4679 gcc_assert (GET_CODE (ret_ptr) == PLUS
4680 && REG_P (XEXP (ret_ptr, 0))
4681 && GET_CODE (XEXP (ret_ptr, 1)) == CONST_INT);
4682 base = gen_rtx_REG (Pmode, REGNO (XEXP (ret_ptr, 0)));
4683 offset = INTVAL (XEXP (ret_ptr, 1));
4687 /* If the base of the location containing the return pointer
4688 is SP, we must update it with the replacement address. Otherwise,
4689 just build the necessary MEM. */
4690 retaddr = plus_constant (base, offset);
4691 if (base == stack_pointer_rtx)
4692 retaddr = simplify_replace_rtx (retaddr, stack_pointer_rtx,
4693 plus_constant (info.sp_equiv_reg,
4694 info.sp_offset));
4696 retaddr = gen_rtx_MEM (Pmode, retaddr);
4698 /* If there is a pending load to the equivalent register for SP
4699 and we reference that register, we must load our address into
4700 a scratch register and then do that load. */
4701 if (info.equiv_reg_src
4702 && reg_overlap_mentioned_p (info.equiv_reg_src, retaddr))
4704 unsigned int regno;
4705 rtx reg;
4707 for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
4708 if (HARD_REGNO_MODE_OK (regno, Pmode)
4709 && !fixed_regs[regno]
4710 && TEST_HARD_REG_BIT (regs_invalidated_by_call, regno)
4711 && !REGNO_REG_SET_P (EXIT_BLOCK_PTR->global_live_at_start,
4712 regno)
4713 && !refers_to_regno_p (regno,
4714 regno + hard_regno_nregs[regno]
4715 [Pmode],
4716 info.equiv_reg_src, NULL)
4717 && info.const_equiv[regno] == 0)
4718 break;
4720 gcc_assert (regno < FIRST_PSEUDO_REGISTER);
4722 reg = gen_rtx_REG (Pmode, regno);
4723 emit_move_insn (reg, retaddr);
4724 retaddr = reg;
4727 emit_equiv_load (&info);
4728 jump_insn = emit_jump_insn (gen_indirect_jump (retaddr));
4730 /* Show the SET in the above insn is a RETURN. */
4731 jump_set = single_set (jump_insn);
4732 gcc_assert (jump_set);
4733 SET_IS_RETURN_P (jump_set) = 1;
4736 /* If SP is not mentioned in the pattern and its equivalent register, if
4737 any, is not modified, just emit it. Otherwise, if neither is set,
4738 replace the reference to SP and emit the insn. If none of those are
4739 true, handle each SET individually. */
4740 else if (!reg_mentioned_p (stack_pointer_rtx, PATTERN (insn))
4741 && (info.sp_equiv_reg == stack_pointer_rtx
4742 || !reg_set_p (info.sp_equiv_reg, insn)))
4743 add_insn (insn);
4744 else if (! reg_set_p (stack_pointer_rtx, insn)
4745 && (info.sp_equiv_reg == stack_pointer_rtx
4746 || !reg_set_p (info.sp_equiv_reg, insn)))
4748 int changed;
4750 changed = validate_replace_rtx (stack_pointer_rtx,
4751 plus_constant (info.sp_equiv_reg,
4752 info.sp_offset),
4753 insn);
4754 gcc_assert (changed);
4756 add_insn (insn);
4758 else if (GET_CODE (PATTERN (insn)) == SET)
4759 handle_epilogue_set (PATTERN (insn), &info);
4760 else if (GET_CODE (PATTERN (insn)) == PARALLEL)
4762 for (j = 0; j < XVECLEN (PATTERN (insn), 0); j++)
4763 if (GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET)
4764 handle_epilogue_set (XVECEXP (PATTERN (insn), 0, j), &info);
4766 else
4767 add_insn (insn);
4769 info.sp_equiv_reg = info.new_sp_equiv_reg;
4770 info.sp_offset = info.new_sp_offset;
4772 /* Now update any constants this insn sets. */
4773 note_stores (PATTERN (insn), update_epilogue_consts, &info);
4774 insn = next;
4777 insns = get_insns ();
4778 end_sequence ();
4779 return insns;
4782 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
4783 structure that contains information about what we've seen so far. We
4784 process this SET by either updating that data or by emitting one or
4785 more insns. */
4787 static void
4788 handle_epilogue_set (rtx set, struct epi_info *p)
4790 /* First handle the case where we are setting SP. Record what it is being
4791 set from, which we must be able to determine */
4792 if (reg_set_p (stack_pointer_rtx, set))
4794 gcc_assert (SET_DEST (set) == stack_pointer_rtx);
4796 if (GET_CODE (SET_SRC (set)) == PLUS)
4798 p->new_sp_equiv_reg = XEXP (SET_SRC (set), 0);
4799 if (GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT)
4800 p->new_sp_offset = INTVAL (XEXP (SET_SRC (set), 1));
4801 else
4803 gcc_assert (REG_P (XEXP (SET_SRC (set), 1))
4804 && (REGNO (XEXP (SET_SRC (set), 1))
4805 < FIRST_PSEUDO_REGISTER)
4806 && p->const_equiv[REGNO (XEXP (SET_SRC (set), 1))]);
4807 p->new_sp_offset
4808 = INTVAL (p->const_equiv[REGNO (XEXP (SET_SRC (set), 1))]);
4811 else
4812 p->new_sp_equiv_reg = SET_SRC (set), p->new_sp_offset = 0;
4814 /* If we are adjusting SP, we adjust from the old data. */
4815 if (p->new_sp_equiv_reg == stack_pointer_rtx)
4817 p->new_sp_equiv_reg = p->sp_equiv_reg;
4818 p->new_sp_offset += p->sp_offset;
4821 gcc_assert (p->new_sp_equiv_reg && REG_P (p->new_sp_equiv_reg));
4823 return;
4826 /* Next handle the case where we are setting SP's equivalent
4827 register. We must not already have a value to set it to. We
4828 could update, but there seems little point in handling that case.
4829 Note that we have to allow for the case where we are setting the
4830 register set in the previous part of a PARALLEL inside a single
4831 insn. But use the old offset for any updates within this insn.
4832 We must allow for the case where the register is being set in a
4833 different (usually wider) mode than Pmode). */
4834 else if (p->new_sp_equiv_reg != 0 && reg_set_p (p->new_sp_equiv_reg, set))
4836 gcc_assert (!p->equiv_reg_src
4837 && REG_P (p->new_sp_equiv_reg)
4838 && REG_P (SET_DEST (set))
4839 && (GET_MODE_BITSIZE (GET_MODE (SET_DEST (set)))
4840 <= BITS_PER_WORD)
4841 && REGNO (p->new_sp_equiv_reg) == REGNO (SET_DEST (set)));
4842 p->equiv_reg_src
4843 = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
4844 plus_constant (p->sp_equiv_reg,
4845 p->sp_offset));
4848 /* Otherwise, replace any references to SP in the insn to its new value
4849 and emit the insn. */
4850 else
4852 SET_SRC (set) = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
4853 plus_constant (p->sp_equiv_reg,
4854 p->sp_offset));
4855 SET_DEST (set) = simplify_replace_rtx (SET_DEST (set), stack_pointer_rtx,
4856 plus_constant (p->sp_equiv_reg,
4857 p->sp_offset));
4858 emit_insn (set);
4862 /* Update the tracking information for registers set to constants. */
4864 static void
4865 update_epilogue_consts (rtx dest, rtx x, void *data)
4867 struct epi_info *p = (struct epi_info *) data;
4868 rtx new;
4870 if (!REG_P (dest) || REGNO (dest) >= FIRST_PSEUDO_REGISTER)
4871 return;
4873 /* If we are either clobbering a register or doing a partial set,
4874 show we don't know the value. */
4875 else if (GET_CODE (x) == CLOBBER || ! rtx_equal_p (dest, SET_DEST (x)))
4876 p->const_equiv[REGNO (dest)] = 0;
4878 /* If we are setting it to a constant, record that constant. */
4879 else if (GET_CODE (SET_SRC (x)) == CONST_INT)
4880 p->const_equiv[REGNO (dest)] = SET_SRC (x);
4882 /* If this is a binary operation between a register we have been tracking
4883 and a constant, see if we can compute a new constant value. */
4884 else if (ARITHMETIC_P (SET_SRC (x))
4885 && REG_P (XEXP (SET_SRC (x), 0))
4886 && REGNO (XEXP (SET_SRC (x), 0)) < FIRST_PSEUDO_REGISTER
4887 && p->const_equiv[REGNO (XEXP (SET_SRC (x), 0))] != 0
4888 && GET_CODE (XEXP (SET_SRC (x), 1)) == CONST_INT
4889 && 0 != (new = simplify_binary_operation
4890 (GET_CODE (SET_SRC (x)), GET_MODE (dest),
4891 p->const_equiv[REGNO (XEXP (SET_SRC (x), 0))],
4892 XEXP (SET_SRC (x), 1)))
4893 && GET_CODE (new) == CONST_INT)
4894 p->const_equiv[REGNO (dest)] = new;
4896 /* Otherwise, we can't do anything with this value. */
4897 else
4898 p->const_equiv[REGNO (dest)] = 0;
4901 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
4903 static void
4904 emit_equiv_load (struct epi_info *p)
4906 if (p->equiv_reg_src != 0)
4908 rtx dest = p->sp_equiv_reg;
4910 if (GET_MODE (p->equiv_reg_src) != GET_MODE (dest))
4911 dest = gen_rtx_REG (GET_MODE (p->equiv_reg_src),
4912 REGNO (p->sp_equiv_reg));
4914 emit_move_insn (dest, p->equiv_reg_src);
4915 p->equiv_reg_src = 0;
4918 #endif
4920 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
4921 this into place with notes indicating where the prologue ends and where
4922 the epilogue begins. Update the basic block information when possible. */
4924 void
4925 thread_prologue_and_epilogue_insns (rtx f ATTRIBUTE_UNUSED)
4927 int inserted = 0;
4928 edge e;
4929 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
4930 rtx seq;
4931 #endif
4932 #ifdef HAVE_prologue
4933 rtx prologue_end = NULL_RTX;
4934 #endif
4935 #if defined (HAVE_epilogue) || defined(HAVE_return)
4936 rtx epilogue_end = NULL_RTX;
4937 #endif
4938 edge_iterator ei;
4940 #ifdef HAVE_prologue
4941 if (HAVE_prologue)
4943 start_sequence ();
4944 seq = gen_prologue ();
4945 emit_insn (seq);
4947 /* Retain a map of the prologue insns. */
4948 record_insns (seq, &prologue);
4949 prologue_end = emit_note (NOTE_INSN_PROLOGUE_END);
4951 seq = get_insns ();
4952 end_sequence ();
4953 set_insn_locators (seq, prologue_locator);
4955 /* Can't deal with multiple successors of the entry block
4956 at the moment. Function should always have at least one
4957 entry point. */
4958 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR));
4960 insert_insn_on_edge (seq, single_succ_edge (ENTRY_BLOCK_PTR));
4961 inserted = 1;
4963 #endif
4965 /* If the exit block has no non-fake predecessors, we don't need
4966 an epilogue. */
4967 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
4968 if ((e->flags & EDGE_FAKE) == 0)
4969 break;
4970 if (e == NULL)
4971 goto epilogue_done;
4973 #ifdef HAVE_return
4974 if (optimize && HAVE_return)
4976 /* If we're allowed to generate a simple return instruction,
4977 then by definition we don't need a full epilogue. Examine
4978 the block that falls through to EXIT. If it does not
4979 contain any code, examine its predecessors and try to
4980 emit (conditional) return instructions. */
4982 basic_block last;
4983 rtx label;
4985 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
4986 if (e->flags & EDGE_FALLTHRU)
4987 break;
4988 if (e == NULL)
4989 goto epilogue_done;
4990 last = e->src;
4992 /* Verify that there are no active instructions in the last block. */
4993 label = BB_END (last);
4994 while (label && !LABEL_P (label))
4996 if (active_insn_p (label))
4997 break;
4998 label = PREV_INSN (label);
5001 if (BB_HEAD (last) == label && LABEL_P (label))
5003 edge_iterator ei2;
5004 rtx epilogue_line_note = NULL_RTX;
5006 /* Locate the line number associated with the closing brace,
5007 if we can find one. */
5008 for (seq = get_last_insn ();
5009 seq && ! active_insn_p (seq);
5010 seq = PREV_INSN (seq))
5011 if (NOTE_P (seq) && NOTE_LINE_NUMBER (seq) > 0)
5013 epilogue_line_note = seq;
5014 break;
5017 for (ei2 = ei_start (last->preds); (e = ei_safe_edge (ei2)); )
5019 basic_block bb = e->src;
5020 rtx jump;
5022 if (bb == ENTRY_BLOCK_PTR)
5024 ei_next (&ei2);
5025 continue;
5028 jump = BB_END (bb);
5029 if (!JUMP_P (jump) || JUMP_LABEL (jump) != label)
5031 ei_next (&ei2);
5032 continue;
5035 /* If we have an unconditional jump, we can replace that
5036 with a simple return instruction. */
5037 if (simplejump_p (jump))
5039 emit_return_into_block (bb, epilogue_line_note);
5040 delete_insn (jump);
5043 /* If we have a conditional jump, we can try to replace
5044 that with a conditional return instruction. */
5045 else if (condjump_p (jump))
5047 if (! redirect_jump (jump, 0, 0))
5049 ei_next (&ei2);
5050 continue;
5053 /* If this block has only one successor, it both jumps
5054 and falls through to the fallthru block, so we can't
5055 delete the edge. */
5056 if (single_succ_p (bb))
5058 ei_next (&ei2);
5059 continue;
5062 else
5064 ei_next (&ei2);
5065 continue;
5068 /* Fix up the CFG for the successful change we just made. */
5069 redirect_edge_succ (e, EXIT_BLOCK_PTR);
5072 /* Emit a return insn for the exit fallthru block. Whether
5073 this is still reachable will be determined later. */
5075 emit_barrier_after (BB_END (last));
5076 emit_return_into_block (last, epilogue_line_note);
5077 epilogue_end = BB_END (last);
5078 single_succ_edge (last)->flags &= ~EDGE_FALLTHRU;
5079 goto epilogue_done;
5082 #endif
5083 /* Find the edge that falls through to EXIT. Other edges may exist
5084 due to RETURN instructions, but those don't need epilogues.
5085 There really shouldn't be a mixture -- either all should have
5086 been converted or none, however... */
5088 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5089 if (e->flags & EDGE_FALLTHRU)
5090 break;
5091 if (e == NULL)
5092 goto epilogue_done;
5094 #ifdef HAVE_epilogue
5095 if (HAVE_epilogue)
5097 start_sequence ();
5098 epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG);
5100 seq = gen_epilogue ();
5102 #ifdef INCOMING_RETURN_ADDR_RTX
5103 /* If this function returns with the stack depressed and we can support
5104 it, massage the epilogue to actually do that. */
5105 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
5106 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
5107 seq = keep_stack_depressed (seq);
5108 #endif
5110 emit_jump_insn (seq);
5112 /* Retain a map of the epilogue insns. */
5113 record_insns (seq, &epilogue);
5114 set_insn_locators (seq, epilogue_locator);
5116 seq = get_insns ();
5117 end_sequence ();
5119 insert_insn_on_edge (seq, e);
5120 inserted = 1;
5122 else
5123 #endif
5125 basic_block cur_bb;
5127 if (! next_active_insn (BB_END (e->src)))
5128 goto epilogue_done;
5129 /* We have a fall-through edge to the exit block, the source is not
5130 at the end of the function, and there will be an assembler epilogue
5131 at the end of the function.
5132 We can't use force_nonfallthru here, because that would try to
5133 use return. Inserting a jump 'by hand' is extremely messy, so
5134 we take advantage of cfg_layout_finalize using
5135 fixup_fallthru_exit_predecessor. */
5136 cfg_layout_initialize (0);
5137 FOR_EACH_BB (cur_bb)
5138 if (cur_bb->index >= 0 && cur_bb->next_bb->index >= 0)
5139 cur_bb->rbi->next = cur_bb->next_bb;
5140 cfg_layout_finalize ();
5142 epilogue_done:
5144 if (inserted)
5145 commit_edge_insertions ();
5147 #ifdef HAVE_sibcall_epilogue
5148 /* Emit sibling epilogues before any sibling call sites. */
5149 for (ei = ei_start (EXIT_BLOCK_PTR->preds); (e = ei_safe_edge (ei)); )
5151 basic_block bb = e->src;
5152 rtx insn = BB_END (bb);
5154 if (!CALL_P (insn)
5155 || ! SIBLING_CALL_P (insn))
5157 ei_next (&ei);
5158 continue;
5161 start_sequence ();
5162 emit_insn (gen_sibcall_epilogue ());
5163 seq = get_insns ();
5164 end_sequence ();
5166 /* Retain a map of the epilogue insns. Used in life analysis to
5167 avoid getting rid of sibcall epilogue insns. Do this before we
5168 actually emit the sequence. */
5169 record_insns (seq, &sibcall_epilogue);
5170 set_insn_locators (seq, epilogue_locator);
5172 emit_insn_before (seq, insn);
5173 ei_next (&ei);
5175 #endif
5177 #ifdef HAVE_prologue
5178 /* This is probably all useless now that we use locators. */
5179 if (prologue_end)
5181 rtx insn, prev;
5183 /* GDB handles `break f' by setting a breakpoint on the first
5184 line note after the prologue. Which means (1) that if
5185 there are line number notes before where we inserted the
5186 prologue we should move them, and (2) we should generate a
5187 note before the end of the first basic block, if there isn't
5188 one already there.
5190 ??? This behavior is completely broken when dealing with
5191 multiple entry functions. We simply place the note always
5192 into first basic block and let alternate entry points
5193 to be missed.
5196 for (insn = prologue_end; insn; insn = prev)
5198 prev = PREV_INSN (insn);
5199 if (NOTE_P (insn) && NOTE_LINE_NUMBER (insn) > 0)
5201 /* Note that we cannot reorder the first insn in the
5202 chain, since rest_of_compilation relies on that
5203 remaining constant. */
5204 if (prev == NULL)
5205 break;
5206 reorder_insns (insn, insn, prologue_end);
5210 /* Find the last line number note in the first block. */
5211 for (insn = BB_END (ENTRY_BLOCK_PTR->next_bb);
5212 insn != prologue_end && insn;
5213 insn = PREV_INSN (insn))
5214 if (NOTE_P (insn) && NOTE_LINE_NUMBER (insn) > 0)
5215 break;
5217 /* If we didn't find one, make a copy of the first line number
5218 we run across. */
5219 if (! insn)
5221 for (insn = next_active_insn (prologue_end);
5222 insn;
5223 insn = PREV_INSN (insn))
5224 if (NOTE_P (insn) && NOTE_LINE_NUMBER (insn) > 0)
5226 emit_note_copy_after (insn, prologue_end);
5227 break;
5231 #endif
5232 #ifdef HAVE_epilogue
5233 if (epilogue_end)
5235 rtx insn, next;
5237 /* Similarly, move any line notes that appear after the epilogue.
5238 There is no need, however, to be quite so anal about the existence
5239 of such a note. Also move the NOTE_INSN_FUNCTION_END and (possibly)
5240 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
5241 info generation. */
5242 for (insn = epilogue_end; insn; insn = next)
5244 next = NEXT_INSN (insn);
5245 if (NOTE_P (insn)
5246 && (NOTE_LINE_NUMBER (insn) > 0
5247 || NOTE_LINE_NUMBER (insn) == NOTE_INSN_FUNCTION_BEG
5248 || NOTE_LINE_NUMBER (insn) == NOTE_INSN_FUNCTION_END))
5249 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
5252 #endif
5255 /* Reposition the prologue-end and epilogue-begin notes after instruction
5256 scheduling and delayed branch scheduling. */
5258 void
5259 reposition_prologue_and_epilogue_notes (rtx f ATTRIBUTE_UNUSED)
5261 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
5262 rtx insn, last, note;
5263 int len;
5265 if ((len = VARRAY_SIZE (prologue)) > 0)
5267 last = 0, note = 0;
5269 /* Scan from the beginning until we reach the last prologue insn.
5270 We apparently can't depend on basic_block_{head,end} after
5271 reorg has run. */
5272 for (insn = f; insn; insn = NEXT_INSN (insn))
5274 if (NOTE_P (insn))
5276 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
5277 note = insn;
5279 else if (contains (insn, prologue))
5281 last = insn;
5282 if (--len == 0)
5283 break;
5287 if (last)
5289 /* Find the prologue-end note if we haven't already, and
5290 move it to just after the last prologue insn. */
5291 if (note == 0)
5293 for (note = last; (note = NEXT_INSN (note));)
5294 if (NOTE_P (note)
5295 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
5296 break;
5299 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
5300 if (LABEL_P (last))
5301 last = NEXT_INSN (last);
5302 reorder_insns (note, note, last);
5306 if ((len = VARRAY_SIZE (epilogue)) > 0)
5308 last = 0, note = 0;
5310 /* Scan from the end until we reach the first epilogue insn.
5311 We apparently can't depend on basic_block_{head,end} after
5312 reorg has run. */
5313 for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
5315 if (NOTE_P (insn))
5317 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
5318 note = insn;
5320 else if (contains (insn, epilogue))
5322 last = insn;
5323 if (--len == 0)
5324 break;
5328 if (last)
5330 /* Find the epilogue-begin note if we haven't already, and
5331 move it to just before the first epilogue insn. */
5332 if (note == 0)
5334 for (note = insn; (note = PREV_INSN (note));)
5335 if (NOTE_P (note)
5336 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
5337 break;
5340 if (PREV_INSN (last) != note)
5341 reorder_insns (note, note, PREV_INSN (last));
5344 #endif /* HAVE_prologue or HAVE_epilogue */
5347 /* Called once, at initialization, to initialize function.c. */
5349 void
5350 init_function_once (void)
5352 VARRAY_INT_INIT (prologue, 0, "prologue");
5353 VARRAY_INT_INIT (epilogue, 0, "epilogue");
5354 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");
5357 /* Resets insn_block_boundaries array. */
5359 void
5360 reset_block_changes (void)
5362 VARRAY_TREE_INIT (cfun->ib_boundaries_block, 100, "ib_boundaries_block");
5363 VARRAY_PUSH_TREE (cfun->ib_boundaries_block, NULL_TREE);
5366 /* Record the boundary for BLOCK. */
5367 void
5368 record_block_change (tree block)
5370 int i, n;
5371 tree last_block;
5373 if (!block)
5374 return;
5376 last_block = VARRAY_TOP_TREE (cfun->ib_boundaries_block);
5377 VARRAY_POP (cfun->ib_boundaries_block);
5378 n = get_max_uid ();
5379 for (i = VARRAY_ACTIVE_SIZE (cfun->ib_boundaries_block); i < n; i++)
5380 VARRAY_PUSH_TREE (cfun->ib_boundaries_block, last_block);
5382 VARRAY_PUSH_TREE (cfun->ib_boundaries_block, block);
5385 /* Finishes record of boundaries. */
5386 void finalize_block_changes (void)
5388 record_block_change (DECL_INITIAL (current_function_decl));
5391 /* For INSN return the BLOCK it belongs to. */
5392 void
5393 check_block_change (rtx insn, tree *block)
5395 unsigned uid = INSN_UID (insn);
5397 if (uid >= VARRAY_ACTIVE_SIZE (cfun->ib_boundaries_block))
5398 return;
5400 *block = VARRAY_TREE (cfun->ib_boundaries_block, uid);
5403 /* Releases the ib_boundaries_block records. */
5404 void
5405 free_block_changes (void)
5407 cfun->ib_boundaries_block = NULL;
5410 /* Returns the name of the current function. */
5411 const char *
5412 current_function_name (void)
5414 return lang_hooks.decl_printable_name (cfun->decl, 2);
5417 #include "gt-function.h"