1 /* Expands front end tree to back end RTL for GCC.
2 Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
4 2010 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
22 /* This file handles the generation of rtl code from tree structure
23 at the level of the function as a whole.
24 It creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 `expand_function_start' is called at the beginning of a function,
28 before the function body is parsed, and `expand_function_end' is
29 called after parsing the body.
31 Call `assign_stack_local' to allocate a stack slot for a local variable.
32 This is usually done during the RTL generation for the function body,
33 but it can also be done in the reload pass when a pseudo-register does
34 not get a hard register. */
38 #include "coretypes.h"
40 #include "rtl-error.h"
49 #include "hard-reg-set.h"
50 #include "insn-config.h"
53 #include "basic-block.h"
57 #include "integrate.h"
58 #include "langhooks.h"
60 #include "cfglayout.h"
62 #include "tree-pass.h"
68 /* So we can assign to cfun in this file. */
71 #ifndef STACK_ALIGNMENT_NEEDED
72 #define STACK_ALIGNMENT_NEEDED 1
75 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
77 /* Some systems use __main in a way incompatible with its use in gcc, in these
78 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
79 give the same symbol without quotes for an alternative entry point. You
80 must define both, or neither. */
82 #define NAME__MAIN "__main"
85 /* Round a value to the lowest integer less than it that is a multiple of
86 the required alignment. Avoid using division in case the value is
87 negative. Assume the alignment is a power of two. */
88 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
90 /* Similar, but round to the next highest integer that meets the
92 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
94 /* Nonzero if function being compiled doesn't contain any calls
95 (ignoring the prologue and epilogue). This is set prior to
96 local register allocation and is valid for the remaining
98 int current_function_is_leaf;
100 /* Nonzero if function being compiled doesn't modify the stack pointer
101 (ignoring the prologue and epilogue). This is only valid after
102 pass_stack_ptr_mod has run. */
103 int current_function_sp_is_unchanging;
105 /* Nonzero if the function being compiled is a leaf function which only
106 uses leaf registers. This is valid after reload (specifically after
107 sched2) and is useful only if the port defines LEAF_REGISTERS. */
108 int current_function_uses_only_leaf_regs;
110 /* Nonzero once virtual register instantiation has been done.
111 assign_stack_local uses frame_pointer_rtx when this is nonzero.
112 calls.c:emit_library_call_value_1 uses it to set up
113 post-instantiation libcalls. */
114 int virtuals_instantiated;
116 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
117 static GTY(()) int funcdef_no;
119 /* These variables hold pointers to functions to create and destroy
120 target specific, per-function data structures. */
121 struct machine_function * (*init_machine_status) (void);
123 /* The currently compiled function. */
124 struct function *cfun = 0;
126 /* These hashes record the prologue and epilogue insns. */
127 static GTY((if_marked ("ggc_marked_p"), param_is (struct rtx_def)))
128 htab_t prologue_insn_hash;
129 static GTY((if_marked ("ggc_marked_p"), param_is (struct rtx_def)))
130 htab_t epilogue_insn_hash;
133 htab_t types_used_by_vars_hash = NULL;
134 VEC(tree,gc) *types_used_by_cur_var_decl;
136 /* Forward declarations. */
138 static struct temp_slot *find_temp_slot_from_address (rtx);
139 static void pad_to_arg_alignment (struct args_size *, int, struct args_size *);
140 static void pad_below (struct args_size *, enum machine_mode, tree);
141 static void reorder_blocks_1 (rtx, tree, VEC(tree,heap) **);
142 static int all_blocks (tree, tree *);
143 static tree *get_block_vector (tree, int *);
144 extern tree debug_find_var_in_block_tree (tree, tree);
145 /* We always define `record_insns' even if it's not used so that we
146 can always export `prologue_epilogue_contains'. */
147 static void record_insns (rtx, rtx, htab_t *) ATTRIBUTE_UNUSED;
148 static bool contains (const_rtx, htab_t);
150 static void emit_return_into_block (basic_block);
152 static void prepare_function_start (void);
153 static void do_clobber_return_reg (rtx, void *);
154 static void do_use_return_reg (rtx, void *);
155 static void set_insn_locators (rtx, int) ATTRIBUTE_UNUSED;
157 /* Stack of nested functions. */
158 /* Keep track of the cfun stack. */
160 typedef struct function *function_p;
162 DEF_VEC_P(function_p);
163 DEF_VEC_ALLOC_P(function_p,heap);
164 static VEC(function_p,heap) *function_context_stack;
166 /* Save the current context for compilation of a nested function.
167 This is called from language-specific code. */
170 push_function_context (void)
173 allocate_struct_function (NULL, false);
175 VEC_safe_push (function_p, heap, function_context_stack, cfun);
179 /* Restore the last saved context, at the end of a nested function.
180 This function is called from language-specific code. */
183 pop_function_context (void)
185 struct function *p = VEC_pop (function_p, function_context_stack);
187 current_function_decl = p->decl;
189 /* Reset variables that have known state during rtx generation. */
190 virtuals_instantiated = 0;
191 generating_concat_p = 1;
194 /* Clear out all parts of the state in F that can safely be discarded
195 after the function has been parsed, but not compiled, to let
196 garbage collection reclaim the memory. */
199 free_after_parsing (struct function *f)
204 /* Clear out all parts of the state in F that can safely be discarded
205 after the function has been compiled, to let garbage collection
206 reclaim the memory. */
209 free_after_compilation (struct function *f)
211 prologue_insn_hash = NULL;
212 epilogue_insn_hash = NULL;
214 if (crtl->emit.regno_pointer_align)
215 free (crtl->emit.regno_pointer_align);
217 memset (crtl, 0, sizeof (struct rtl_data));
222 regno_reg_rtx = NULL;
223 insn_locators_free ();
226 /* Return size needed for stack frame based on slots so far allocated.
227 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
228 the caller may have to do that. */
231 get_frame_size (void)
233 if (FRAME_GROWS_DOWNWARD)
234 return -frame_offset;
239 /* Issue an error message and return TRUE if frame OFFSET overflows in
240 the signed target pointer arithmetics for function FUNC. Otherwise
244 frame_offset_overflow (HOST_WIDE_INT offset, tree func)
246 unsigned HOST_WIDE_INT size = FRAME_GROWS_DOWNWARD ? -offset : offset;
248 if (size > ((unsigned HOST_WIDE_INT) 1 << (GET_MODE_BITSIZE (Pmode) - 1))
249 /* Leave room for the fixed part of the frame. */
250 - 64 * UNITS_PER_WORD)
252 error_at (DECL_SOURCE_LOCATION (func),
253 "total size of local objects too large");
260 /* Return stack slot alignment in bits for TYPE and MODE. */
263 get_stack_local_alignment (tree type, enum machine_mode mode)
265 unsigned int alignment;
268 alignment = BIGGEST_ALIGNMENT;
270 alignment = GET_MODE_ALIGNMENT (mode);
272 /* Allow the frond-end to (possibly) increase the alignment of this
275 type = lang_hooks.types.type_for_mode (mode, 0);
277 return STACK_SLOT_ALIGNMENT (type, mode, alignment);
280 /* Determine whether it is possible to fit a stack slot of size SIZE and
281 alignment ALIGNMENT into an area in the stack frame that starts at
282 frame offset START and has a length of LENGTH. If so, store the frame
283 offset to be used for the stack slot in *POFFSET and return true;
284 return false otherwise. This function will extend the frame size when
285 given a start/length pair that lies at the end of the frame. */
288 try_fit_stack_local (HOST_WIDE_INT start, HOST_WIDE_INT length,
289 HOST_WIDE_INT size, unsigned int alignment,
290 HOST_WIDE_INT *poffset)
292 HOST_WIDE_INT this_frame_offset;
293 int frame_off, frame_alignment, frame_phase;
295 /* Calculate how many bytes the start of local variables is off from
297 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
298 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
299 frame_phase = frame_off ? frame_alignment - frame_off : 0;
301 /* Round the frame offset to the specified alignment. */
303 /* We must be careful here, since FRAME_OFFSET might be negative and
304 division with a negative dividend isn't as well defined as we might
305 like. So we instead assume that ALIGNMENT is a power of two and
306 use logical operations which are unambiguous. */
307 if (FRAME_GROWS_DOWNWARD)
309 = (FLOOR_ROUND (start + length - size - frame_phase,
310 (unsigned HOST_WIDE_INT) alignment)
314 = (CEIL_ROUND (start - frame_phase,
315 (unsigned HOST_WIDE_INT) alignment)
318 /* See if it fits. If this space is at the edge of the frame,
319 consider extending the frame to make it fit. Our caller relies on
320 this when allocating a new slot. */
321 if (frame_offset == start && this_frame_offset < frame_offset)
322 frame_offset = this_frame_offset;
323 else if (this_frame_offset < start)
325 else if (start + length == frame_offset
326 && this_frame_offset + size > start + length)
327 frame_offset = this_frame_offset + size;
328 else if (this_frame_offset + size > start + length)
331 *poffset = this_frame_offset;
335 /* Create a new frame_space structure describing free space in the stack
336 frame beginning at START and ending at END, and chain it into the
337 function's frame_space_list. */
340 add_frame_space (HOST_WIDE_INT start, HOST_WIDE_INT end)
342 struct frame_space *space = ggc_alloc_frame_space ();
343 space->next = crtl->frame_space_list;
344 crtl->frame_space_list = space;
345 space->start = start;
346 space->length = end - start;
349 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
350 with machine mode MODE.
352 ALIGN controls the amount of alignment for the address of the slot:
353 0 means according to MODE,
354 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
355 -2 means use BITS_PER_UNIT,
356 positive specifies alignment boundary in bits.
358 If REDUCE_ALIGNMENT_OK is true, it is OK to reduce alignment.
360 We do not round to stack_boundary here. */
363 assign_stack_local_1 (enum machine_mode mode, HOST_WIDE_INT size,
365 bool reduce_alignment_ok ATTRIBUTE_UNUSED)
368 int bigend_correction = 0;
369 HOST_WIDE_INT slot_offset = 0, old_frame_offset;
370 unsigned int alignment, alignment_in_bits;
374 alignment = get_stack_local_alignment (NULL, mode);
375 alignment /= BITS_PER_UNIT;
377 else if (align == -1)
379 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
380 size = CEIL_ROUND (size, alignment);
382 else if (align == -2)
383 alignment = 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
385 alignment = align / BITS_PER_UNIT;
387 alignment_in_bits = alignment * BITS_PER_UNIT;
389 /* Ignore alignment if it exceeds MAX_SUPPORTED_STACK_ALIGNMENT. */
390 if (alignment_in_bits > MAX_SUPPORTED_STACK_ALIGNMENT)
392 alignment_in_bits = MAX_SUPPORTED_STACK_ALIGNMENT;
393 alignment = alignment_in_bits / BITS_PER_UNIT;
396 if (SUPPORTS_STACK_ALIGNMENT)
398 if (crtl->stack_alignment_estimated < alignment_in_bits)
400 if (!crtl->stack_realign_processed)
401 crtl->stack_alignment_estimated = alignment_in_bits;
404 /* If stack is realigned and stack alignment value
405 hasn't been finalized, it is OK not to increase
406 stack_alignment_estimated. The bigger alignment
407 requirement is recorded in stack_alignment_needed
409 gcc_assert (!crtl->stack_realign_finalized);
410 if (!crtl->stack_realign_needed)
412 /* It is OK to reduce the alignment as long as the
413 requested size is 0 or the estimated stack
414 alignment >= mode alignment. */
415 gcc_assert (reduce_alignment_ok
417 || (crtl->stack_alignment_estimated
418 >= GET_MODE_ALIGNMENT (mode)));
419 alignment_in_bits = crtl->stack_alignment_estimated;
420 alignment = alignment_in_bits / BITS_PER_UNIT;
426 if (crtl->stack_alignment_needed < alignment_in_bits)
427 crtl->stack_alignment_needed = alignment_in_bits;
428 if (crtl->max_used_stack_slot_alignment < alignment_in_bits)
429 crtl->max_used_stack_slot_alignment = alignment_in_bits;
431 if (mode != BLKmode || size != 0)
433 struct frame_space **psp;
435 for (psp = &crtl->frame_space_list; *psp; psp = &(*psp)->next)
437 struct frame_space *space = *psp;
438 if (!try_fit_stack_local (space->start, space->length, size,
439 alignment, &slot_offset))
442 if (slot_offset > space->start)
443 add_frame_space (space->start, slot_offset);
444 if (slot_offset + size < space->start + space->length)
445 add_frame_space (slot_offset + size,
446 space->start + space->length);
450 else if (!STACK_ALIGNMENT_NEEDED)
452 slot_offset = frame_offset;
456 old_frame_offset = frame_offset;
458 if (FRAME_GROWS_DOWNWARD)
460 frame_offset -= size;
461 try_fit_stack_local (frame_offset, size, size, alignment, &slot_offset);
463 if (slot_offset > frame_offset)
464 add_frame_space (frame_offset, slot_offset);
465 if (slot_offset + size < old_frame_offset)
466 add_frame_space (slot_offset + size, old_frame_offset);
470 frame_offset += size;
471 try_fit_stack_local (old_frame_offset, size, size, alignment, &slot_offset);
473 if (slot_offset > old_frame_offset)
474 add_frame_space (old_frame_offset, slot_offset);
475 if (slot_offset + size < frame_offset)
476 add_frame_space (slot_offset + size, frame_offset);
480 /* On a big-endian machine, if we are allocating more space than we will use,
481 use the least significant bytes of those that are allocated. */
482 if (BYTES_BIG_ENDIAN && mode != BLKmode && GET_MODE_SIZE (mode) < size)
483 bigend_correction = size - GET_MODE_SIZE (mode);
485 /* If we have already instantiated virtual registers, return the actual
486 address relative to the frame pointer. */
487 if (virtuals_instantiated)
488 addr = plus_constant (frame_pointer_rtx,
490 (slot_offset + bigend_correction
491 + STARTING_FRAME_OFFSET, Pmode));
493 addr = plus_constant (virtual_stack_vars_rtx,
495 (slot_offset + bigend_correction,
498 x = gen_rtx_MEM (mode, addr);
499 set_mem_align (x, alignment_in_bits);
500 MEM_NOTRAP_P (x) = 1;
503 = gen_rtx_EXPR_LIST (VOIDmode, x, stack_slot_list);
505 if (frame_offset_overflow (frame_offset, current_function_decl))
511 /* Wrap up assign_stack_local_1 with last parameter as false. */
514 assign_stack_local (enum machine_mode mode, HOST_WIDE_INT size, int align)
516 return assign_stack_local_1 (mode, size, align, false);
520 /* In order to evaluate some expressions, such as function calls returning
521 structures in memory, we need to temporarily allocate stack locations.
522 We record each allocated temporary in the following structure.
524 Associated with each temporary slot is a nesting level. When we pop up
525 one level, all temporaries associated with the previous level are freed.
526 Normally, all temporaries are freed after the execution of the statement
527 in which they were created. However, if we are inside a ({...}) grouping,
528 the result may be in a temporary and hence must be preserved. If the
529 result could be in a temporary, we preserve it if we can determine which
530 one it is in. If we cannot determine which temporary may contain the
531 result, all temporaries are preserved. A temporary is preserved by
532 pretending it was allocated at the previous nesting level.
534 Automatic variables are also assigned temporary slots, at the nesting
535 level where they are defined. They are marked a "kept" so that
536 free_temp_slots will not free them. */
538 struct GTY(()) temp_slot {
539 /* Points to next temporary slot. */
540 struct temp_slot *next;
541 /* Points to previous temporary slot. */
542 struct temp_slot *prev;
543 /* The rtx to used to reference the slot. */
545 /* The size, in units, of the slot. */
547 /* The type of the object in the slot, or zero if it doesn't correspond
548 to a type. We use this to determine whether a slot can be reused.
549 It can be reused if objects of the type of the new slot will always
550 conflict with objects of the type of the old slot. */
552 /* The alignment (in bits) of the slot. */
554 /* Nonzero if this temporary is currently in use. */
556 /* Nonzero if this temporary has its address taken. */
558 /* Nesting level at which this slot is being used. */
560 /* Nonzero if this should survive a call to free_temp_slots. */
562 /* The offset of the slot from the frame_pointer, including extra space
563 for alignment. This info is for combine_temp_slots. */
564 HOST_WIDE_INT base_offset;
565 /* The size of the slot, including extra space for alignment. This
566 info is for combine_temp_slots. */
567 HOST_WIDE_INT full_size;
570 /* A table of addresses that represent a stack slot. The table is a mapping
571 from address RTXen to a temp slot. */
572 static GTY((param_is(struct temp_slot_address_entry))) htab_t temp_slot_address_table;
574 /* Entry for the above hash table. */
575 struct GTY(()) temp_slot_address_entry {
578 struct temp_slot *temp_slot;
581 /* Removes temporary slot TEMP from LIST. */
584 cut_slot_from_list (struct temp_slot *temp, struct temp_slot **list)
587 temp->next->prev = temp->prev;
589 temp->prev->next = temp->next;
593 temp->prev = temp->next = NULL;
596 /* Inserts temporary slot TEMP to LIST. */
599 insert_slot_to_list (struct temp_slot *temp, struct temp_slot **list)
603 (*list)->prev = temp;
608 /* Returns the list of used temp slots at LEVEL. */
610 static struct temp_slot **
611 temp_slots_at_level (int level)
613 if (level >= (int) VEC_length (temp_slot_p, used_temp_slots))
614 VEC_safe_grow_cleared (temp_slot_p, gc, used_temp_slots, level + 1);
616 return &(VEC_address (temp_slot_p, used_temp_slots)[level]);
619 /* Returns the maximal temporary slot level. */
622 max_slot_level (void)
624 if (!used_temp_slots)
627 return VEC_length (temp_slot_p, used_temp_slots) - 1;
630 /* Moves temporary slot TEMP to LEVEL. */
633 move_slot_to_level (struct temp_slot *temp, int level)
635 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
636 insert_slot_to_list (temp, temp_slots_at_level (level));
640 /* Make temporary slot TEMP available. */
643 make_slot_available (struct temp_slot *temp)
645 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
646 insert_slot_to_list (temp, &avail_temp_slots);
651 /* Compute the hash value for an address -> temp slot mapping.
652 The value is cached on the mapping entry. */
654 temp_slot_address_compute_hash (struct temp_slot_address_entry *t)
656 int do_not_record = 0;
657 return hash_rtx (t->address, GET_MODE (t->address),
658 &do_not_record, NULL, false);
661 /* Return the hash value for an address -> temp slot mapping. */
663 temp_slot_address_hash (const void *p)
665 const struct temp_slot_address_entry *t;
666 t = (const struct temp_slot_address_entry *) p;
670 /* Compare two address -> temp slot mapping entries. */
672 temp_slot_address_eq (const void *p1, const void *p2)
674 const struct temp_slot_address_entry *t1, *t2;
675 t1 = (const struct temp_slot_address_entry *) p1;
676 t2 = (const struct temp_slot_address_entry *) p2;
677 return exp_equiv_p (t1->address, t2->address, 0, true);
680 /* Add ADDRESS as an alias of TEMP_SLOT to the addess -> temp slot mapping. */
682 insert_temp_slot_address (rtx address, struct temp_slot *temp_slot)
685 struct temp_slot_address_entry *t = ggc_alloc_temp_slot_address_entry ();
686 t->address = address;
687 t->temp_slot = temp_slot;
688 t->hash = temp_slot_address_compute_hash (t);
689 slot = htab_find_slot_with_hash (temp_slot_address_table, t, t->hash, INSERT);
693 /* Remove an address -> temp slot mapping entry if the temp slot is
694 not in use anymore. Callback for remove_unused_temp_slot_addresses. */
696 remove_unused_temp_slot_addresses_1 (void **slot, void *data ATTRIBUTE_UNUSED)
698 const struct temp_slot_address_entry *t;
699 t = (const struct temp_slot_address_entry *) *slot;
700 if (! t->temp_slot->in_use)
705 /* Remove all mappings of addresses to unused temp slots. */
707 remove_unused_temp_slot_addresses (void)
709 htab_traverse (temp_slot_address_table,
710 remove_unused_temp_slot_addresses_1,
714 /* Find the temp slot corresponding to the object at address X. */
716 static struct temp_slot *
717 find_temp_slot_from_address (rtx x)
720 struct temp_slot_address_entry tmp, *t;
722 /* First try the easy way:
723 See if X exists in the address -> temp slot mapping. */
725 tmp.temp_slot = NULL;
726 tmp.hash = temp_slot_address_compute_hash (&tmp);
727 t = (struct temp_slot_address_entry *)
728 htab_find_with_hash (temp_slot_address_table, &tmp, tmp.hash);
732 /* If we have a sum involving a register, see if it points to a temp
734 if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 0))
735 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
737 else if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 1))
738 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
741 /* Last resort: Address is a virtual stack var address. */
742 if (GET_CODE (x) == PLUS
743 && XEXP (x, 0) == virtual_stack_vars_rtx
744 && CONST_INT_P (XEXP (x, 1)))
747 for (i = max_slot_level (); i >= 0; i--)
748 for (p = *temp_slots_at_level (i); p; p = p->next)
750 if (INTVAL (XEXP (x, 1)) >= p->base_offset
751 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size)
759 /* Allocate a temporary stack slot and record it for possible later
762 MODE is the machine mode to be given to the returned rtx.
764 SIZE is the size in units of the space required. We do no rounding here
765 since assign_stack_local will do any required rounding.
767 KEEP is 1 if this slot is to be retained after a call to
768 free_temp_slots. Automatic variables for a block are allocated
769 with this flag. KEEP values of 2 or 3 were needed respectively
770 for variables whose lifetime is controlled by CLEANUP_POINT_EXPRs
771 or for SAVE_EXPRs, but they are now unused.
773 TYPE is the type that will be used for the stack slot. */
776 assign_stack_temp_for_type (enum machine_mode mode, HOST_WIDE_INT size,
780 struct temp_slot *p, *best_p = 0, *selected = NULL, **pp;
783 /* If SIZE is -1 it means that somebody tried to allocate a temporary
784 of a variable size. */
785 gcc_assert (size != -1);
787 /* These are now unused. */
788 gcc_assert (keep <= 1);
790 align = get_stack_local_alignment (type, mode);
792 /* Try to find an available, already-allocated temporary of the proper
793 mode which meets the size and alignment requirements. Choose the
794 smallest one with the closest alignment.
796 If assign_stack_temp is called outside of the tree->rtl expansion,
797 we cannot reuse the stack slots (that may still refer to
798 VIRTUAL_STACK_VARS_REGNUM). */
799 if (!virtuals_instantiated)
801 for (p = avail_temp_slots; p; p = p->next)
803 if (p->align >= align && p->size >= size
804 && GET_MODE (p->slot) == mode
805 && objects_must_conflict_p (p->type, type)
806 && (best_p == 0 || best_p->size > p->size
807 || (best_p->size == p->size && best_p->align > p->align)))
809 if (p->align == align && p->size == size)
812 cut_slot_from_list (selected, &avail_temp_slots);
821 /* Make our best, if any, the one to use. */
825 cut_slot_from_list (selected, &avail_temp_slots);
827 /* If there are enough aligned bytes left over, make them into a new
828 temp_slot so that the extra bytes don't get wasted. Do this only
829 for BLKmode slots, so that we can be sure of the alignment. */
830 if (GET_MODE (best_p->slot) == BLKmode)
832 int alignment = best_p->align / BITS_PER_UNIT;
833 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
835 if (best_p->size - rounded_size >= alignment)
837 p = ggc_alloc_temp_slot ();
838 p->in_use = p->addr_taken = 0;
839 p->size = best_p->size - rounded_size;
840 p->base_offset = best_p->base_offset + rounded_size;
841 p->full_size = best_p->full_size - rounded_size;
842 p->slot = adjust_address_nv (best_p->slot, BLKmode, rounded_size);
843 p->align = best_p->align;
844 p->type = best_p->type;
845 insert_slot_to_list (p, &avail_temp_slots);
847 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
850 best_p->size = rounded_size;
851 best_p->full_size = rounded_size;
856 /* If we still didn't find one, make a new temporary. */
859 HOST_WIDE_INT frame_offset_old = frame_offset;
861 p = ggc_alloc_temp_slot ();
863 /* We are passing an explicit alignment request to assign_stack_local.
864 One side effect of that is assign_stack_local will not round SIZE
865 to ensure the frame offset remains suitably aligned.
867 So for requests which depended on the rounding of SIZE, we go ahead
868 and round it now. We also make sure ALIGNMENT is at least
869 BIGGEST_ALIGNMENT. */
870 gcc_assert (mode != BLKmode || align == BIGGEST_ALIGNMENT);
871 p->slot = assign_stack_local (mode,
873 ? CEIL_ROUND (size, (int) align / BITS_PER_UNIT)
879 /* The following slot size computation is necessary because we don't
880 know the actual size of the temporary slot until assign_stack_local
881 has performed all the frame alignment and size rounding for the
882 requested temporary. Note that extra space added for alignment
883 can be either above or below this stack slot depending on which
884 way the frame grows. We include the extra space if and only if it
885 is above this slot. */
886 if (FRAME_GROWS_DOWNWARD)
887 p->size = frame_offset_old - frame_offset;
891 /* Now define the fields used by combine_temp_slots. */
892 if (FRAME_GROWS_DOWNWARD)
894 p->base_offset = frame_offset;
895 p->full_size = frame_offset_old - frame_offset;
899 p->base_offset = frame_offset_old;
900 p->full_size = frame_offset - frame_offset_old;
910 p->level = temp_slot_level;
913 pp = temp_slots_at_level (p->level);
914 insert_slot_to_list (p, pp);
915 insert_temp_slot_address (XEXP (p->slot, 0), p);
917 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
918 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
919 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list);
921 /* If we know the alias set for the memory that will be used, use
922 it. If there's no TYPE, then we don't know anything about the
923 alias set for the memory. */
924 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
925 set_mem_align (slot, align);
927 /* If a type is specified, set the relevant flags. */
930 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
931 MEM_SET_IN_STRUCT_P (slot, (AGGREGATE_TYPE_P (type)
932 || TREE_CODE (type) == COMPLEX_TYPE));
934 MEM_NOTRAP_P (slot) = 1;
939 /* Allocate a temporary stack slot and record it for possible later
940 reuse. First three arguments are same as in preceding function. */
943 assign_stack_temp (enum machine_mode mode, HOST_WIDE_INT size, int keep)
945 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
948 /* Assign a temporary.
949 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
950 and so that should be used in error messages. In either case, we
951 allocate of the given type.
952 KEEP is as for assign_stack_temp.
953 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
954 it is 0 if a register is OK.
955 DONT_PROMOTE is 1 if we should not promote values in register
959 assign_temp (tree type_or_decl, int keep, int memory_required,
960 int dont_promote ATTRIBUTE_UNUSED)
963 enum machine_mode mode;
968 if (DECL_P (type_or_decl))
969 decl = type_or_decl, type = TREE_TYPE (decl);
971 decl = NULL, type = type_or_decl;
973 mode = TYPE_MODE (type);
975 unsignedp = TYPE_UNSIGNED (type);
978 if (mode == BLKmode || memory_required)
980 HOST_WIDE_INT size = int_size_in_bytes (type);
983 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
984 problems with allocating the stack space. */
988 /* Unfortunately, we don't yet know how to allocate variable-sized
989 temporaries. However, sometimes we can find a fixed upper limit on
990 the size, so try that instead. */
992 size = max_int_size_in_bytes (type);
994 /* The size of the temporary may be too large to fit into an integer. */
995 /* ??? Not sure this should happen except for user silliness, so limit
996 this to things that aren't compiler-generated temporaries. The
997 rest of the time we'll die in assign_stack_temp_for_type. */
998 if (decl && size == -1
999 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
1001 error ("size of variable %q+D is too large", decl);
1005 tmp = assign_stack_temp_for_type (mode, size, keep, type);
1011 mode = promote_mode (type, mode, &unsignedp);
1014 return gen_reg_rtx (mode);
1017 /* Combine temporary stack slots which are adjacent on the stack.
1019 This allows for better use of already allocated stack space. This is only
1020 done for BLKmode slots because we can be sure that we won't have alignment
1021 problems in this case. */
1024 combine_temp_slots (void)
1026 struct temp_slot *p, *q, *next, *next_q;
1029 /* We can't combine slots, because the information about which slot
1030 is in which alias set will be lost. */
1031 if (flag_strict_aliasing)
1034 /* If there are a lot of temp slots, don't do anything unless
1035 high levels of optimization. */
1036 if (! flag_expensive_optimizations)
1037 for (p = avail_temp_slots, num_slots = 0; p; p = p->next, num_slots++)
1038 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
1041 for (p = avail_temp_slots; p; p = next)
1047 if (GET_MODE (p->slot) != BLKmode)
1050 for (q = p->next; q; q = next_q)
1056 if (GET_MODE (q->slot) != BLKmode)
1059 if (p->base_offset + p->full_size == q->base_offset)
1061 /* Q comes after P; combine Q into P. */
1063 p->full_size += q->full_size;
1066 else if (q->base_offset + q->full_size == p->base_offset)
1068 /* P comes after Q; combine P into Q. */
1070 q->full_size += p->full_size;
1075 cut_slot_from_list (q, &avail_temp_slots);
1078 /* Either delete P or advance past it. */
1080 cut_slot_from_list (p, &avail_temp_slots);
1084 /* Indicate that NEW_RTX is an alternate way of referring to the temp
1085 slot that previously was known by OLD_RTX. */
1088 update_temp_slot_address (rtx old_rtx, rtx new_rtx)
1090 struct temp_slot *p;
1092 if (rtx_equal_p (old_rtx, new_rtx))
1095 p = find_temp_slot_from_address (old_rtx);
1097 /* If we didn't find one, see if both OLD_RTX is a PLUS. If so, and
1098 NEW_RTX is a register, see if one operand of the PLUS is a
1099 temporary location. If so, NEW_RTX points into it. Otherwise,
1100 if both OLD_RTX and NEW_RTX are a PLUS and if there is a register
1101 in common between them. If so, try a recursive call on those
1105 if (GET_CODE (old_rtx) != PLUS)
1108 if (REG_P (new_rtx))
1110 update_temp_slot_address (XEXP (old_rtx, 0), new_rtx);
1111 update_temp_slot_address (XEXP (old_rtx, 1), new_rtx);
1114 else if (GET_CODE (new_rtx) != PLUS)
1117 if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 0)))
1118 update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 1));
1119 else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 0)))
1120 update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 1));
1121 else if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 1)))
1122 update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 0));
1123 else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 1)))
1124 update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 0));
1129 /* Otherwise add an alias for the temp's address. */
1130 insert_temp_slot_address (new_rtx, p);
1133 /* If X could be a reference to a temporary slot, mark the fact that its
1134 address was taken. */
1137 mark_temp_addr_taken (rtx x)
1139 struct temp_slot *p;
1144 /* If X is not in memory or is at a constant address, it cannot be in
1145 a temporary slot. */
1146 if (!MEM_P (x) || CONSTANT_P (XEXP (x, 0)))
1149 p = find_temp_slot_from_address (XEXP (x, 0));
1154 /* If X could be a reference to a temporary slot, mark that slot as
1155 belonging to the to one level higher than the current level. If X
1156 matched one of our slots, just mark that one. Otherwise, we can't
1157 easily predict which it is, so upgrade all of them. Kept slots
1158 need not be touched.
1160 This is called when an ({...}) construct occurs and a statement
1161 returns a value in memory. */
1164 preserve_temp_slots (rtx x)
1166 struct temp_slot *p = 0, *next;
1168 /* If there is no result, we still might have some objects whose address
1169 were taken, so we need to make sure they stay around. */
1172 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1177 move_slot_to_level (p, temp_slot_level - 1);
1183 /* If X is a register that is being used as a pointer, see if we have
1184 a temporary slot we know it points to. To be consistent with
1185 the code below, we really should preserve all non-kept slots
1186 if we can't find a match, but that seems to be much too costly. */
1187 if (REG_P (x) && REG_POINTER (x))
1188 p = find_temp_slot_from_address (x);
1190 /* If X is not in memory or is at a constant address, it cannot be in
1191 a temporary slot, but it can contain something whose address was
1193 if (p == 0 && (!MEM_P (x) || CONSTANT_P (XEXP (x, 0))))
1195 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1200 move_slot_to_level (p, temp_slot_level - 1);
1206 /* First see if we can find a match. */
1208 p = find_temp_slot_from_address (XEXP (x, 0));
1212 /* Move everything at our level whose address was taken to our new
1213 level in case we used its address. */
1214 struct temp_slot *q;
1216 if (p->level == temp_slot_level)
1218 for (q = *temp_slots_at_level (temp_slot_level); q; q = next)
1222 if (p != q && q->addr_taken)
1223 move_slot_to_level (q, temp_slot_level - 1);
1226 move_slot_to_level (p, temp_slot_level - 1);
1232 /* Otherwise, preserve all non-kept slots at this level. */
1233 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1238 move_slot_to_level (p, temp_slot_level - 1);
1242 /* Free all temporaries used so far. This is normally called at the
1243 end of generating code for a statement. */
1246 free_temp_slots (void)
1248 struct temp_slot *p, *next;
1249 bool some_available = false;
1251 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1257 make_slot_available (p);
1258 some_available = true;
1264 remove_unused_temp_slot_addresses ();
1265 combine_temp_slots ();
1269 /* Push deeper into the nesting level for stack temporaries. */
1272 push_temp_slots (void)
1277 /* Pop a temporary nesting level. All slots in use in the current level
1281 pop_temp_slots (void)
1283 struct temp_slot *p, *next;
1284 bool some_available = false;
1286 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1289 make_slot_available (p);
1290 some_available = true;
1295 remove_unused_temp_slot_addresses ();
1296 combine_temp_slots ();
1302 /* Initialize temporary slots. */
1305 init_temp_slots (void)
1307 /* We have not allocated any temporaries yet. */
1308 avail_temp_slots = 0;
1309 used_temp_slots = 0;
1310 temp_slot_level = 0;
1312 /* Set up the table to map addresses to temp slots. */
1313 if (! temp_slot_address_table)
1314 temp_slot_address_table = htab_create_ggc (32,
1315 temp_slot_address_hash,
1316 temp_slot_address_eq,
1319 htab_empty (temp_slot_address_table);
1322 /* These routines are responsible for converting virtual register references
1323 to the actual hard register references once RTL generation is complete.
1325 The following four variables are used for communication between the
1326 routines. They contain the offsets of the virtual registers from their
1327 respective hard registers. */
1329 static int in_arg_offset;
1330 static int var_offset;
1331 static int dynamic_offset;
1332 static int out_arg_offset;
1333 static int cfa_offset;
1335 /* In most machines, the stack pointer register is equivalent to the bottom
1338 #ifndef STACK_POINTER_OFFSET
1339 #define STACK_POINTER_OFFSET 0
1342 /* If not defined, pick an appropriate default for the offset of dynamically
1343 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1344 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1346 #ifndef STACK_DYNAMIC_OFFSET
1348 /* The bottom of the stack points to the actual arguments. If
1349 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1350 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1351 stack space for register parameters is not pushed by the caller, but
1352 rather part of the fixed stack areas and hence not included in
1353 `crtl->outgoing_args_size'. Nevertheless, we must allow
1354 for it when allocating stack dynamic objects. */
1356 #if defined(REG_PARM_STACK_SPACE)
1357 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1358 ((ACCUMULATE_OUTGOING_ARGS \
1359 ? (crtl->outgoing_args_size \
1360 + (OUTGOING_REG_PARM_STACK_SPACE ((!(FNDECL) ? NULL_TREE : TREE_TYPE (FNDECL))) ? 0 \
1361 : REG_PARM_STACK_SPACE (FNDECL))) \
1362 : 0) + (STACK_POINTER_OFFSET))
1364 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1365 ((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : 0) \
1366 + (STACK_POINTER_OFFSET))
1371 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1372 is a virtual register, return the equivalent hard register and set the
1373 offset indirectly through the pointer. Otherwise, return 0. */
1376 instantiate_new_reg (rtx x, HOST_WIDE_INT *poffset)
1379 HOST_WIDE_INT offset;
1381 if (x == virtual_incoming_args_rtx)
1383 if (stack_realign_drap)
1385 /* Replace virtual_incoming_args_rtx with internal arg
1386 pointer if DRAP is used to realign stack. */
1387 new_rtx = crtl->args.internal_arg_pointer;
1391 new_rtx = arg_pointer_rtx, offset = in_arg_offset;
1393 else if (x == virtual_stack_vars_rtx)
1394 new_rtx = frame_pointer_rtx, offset = var_offset;
1395 else if (x == virtual_stack_dynamic_rtx)
1396 new_rtx = stack_pointer_rtx, offset = dynamic_offset;
1397 else if (x == virtual_outgoing_args_rtx)
1398 new_rtx = stack_pointer_rtx, offset = out_arg_offset;
1399 else if (x == virtual_cfa_rtx)
1401 #ifdef FRAME_POINTER_CFA_OFFSET
1402 new_rtx = frame_pointer_rtx;
1404 new_rtx = arg_pointer_rtx;
1406 offset = cfa_offset;
1415 /* A subroutine of instantiate_virtual_regs, called via for_each_rtx.
1416 Instantiate any virtual registers present inside of *LOC. The expression
1417 is simplified, as much as possible, but is not to be considered "valid"
1418 in any sense implied by the target. If any change is made, set CHANGED
1422 instantiate_virtual_regs_in_rtx (rtx *loc, void *data)
1424 HOST_WIDE_INT offset;
1425 bool *changed = (bool *) data;
1432 switch (GET_CODE (x))
1435 new_rtx = instantiate_new_reg (x, &offset);
1438 *loc = plus_constant (new_rtx, offset);
1445 new_rtx = instantiate_new_reg (XEXP (x, 0), &offset);
1448 new_rtx = plus_constant (new_rtx, offset);
1449 *loc = simplify_gen_binary (PLUS, GET_MODE (x), new_rtx, XEXP (x, 1));
1455 /* FIXME -- from old code */
1456 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1457 we can commute the PLUS and SUBREG because pointers into the
1458 frame are well-behaved. */
1468 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1469 matches the predicate for insn CODE operand OPERAND. */
1472 safe_insn_predicate (int code, int operand, rtx x)
1474 const struct insn_operand_data *op_data;
1479 op_data = &insn_data[code].operand[operand];
1480 if (op_data->predicate == NULL)
1483 return op_data->predicate (x, op_data->mode);
1486 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1487 registers present inside of insn. The result will be a valid insn. */
1490 instantiate_virtual_regs_in_insn (rtx insn)
1492 HOST_WIDE_INT offset;
1494 bool any_change = false;
1495 rtx set, new_rtx, x, seq;
1497 /* There are some special cases to be handled first. */
1498 set = single_set (insn);
1501 /* We're allowed to assign to a virtual register. This is interpreted
1502 to mean that the underlying register gets assigned the inverse
1503 transformation. This is used, for example, in the handling of
1505 new_rtx = instantiate_new_reg (SET_DEST (set), &offset);
1510 for_each_rtx (&SET_SRC (set), instantiate_virtual_regs_in_rtx, NULL);
1511 x = simplify_gen_binary (PLUS, GET_MODE (new_rtx), SET_SRC (set),
1513 x = force_operand (x, new_rtx);
1515 emit_move_insn (new_rtx, x);
1520 emit_insn_before (seq, insn);
1525 /* Handle a straight copy from a virtual register by generating a
1526 new add insn. The difference between this and falling through
1527 to the generic case is avoiding a new pseudo and eliminating a
1528 move insn in the initial rtl stream. */
1529 new_rtx = instantiate_new_reg (SET_SRC (set), &offset);
1530 if (new_rtx && offset != 0
1531 && REG_P (SET_DEST (set))
1532 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1536 x = expand_simple_binop (GET_MODE (SET_DEST (set)), PLUS,
1537 new_rtx, GEN_INT (offset), SET_DEST (set),
1538 1, OPTAB_LIB_WIDEN);
1539 if (x != SET_DEST (set))
1540 emit_move_insn (SET_DEST (set), x);
1545 emit_insn_before (seq, insn);
1550 extract_insn (insn);
1551 insn_code = INSN_CODE (insn);
1553 /* Handle a plus involving a virtual register by determining if the
1554 operands remain valid if they're modified in place. */
1555 if (GET_CODE (SET_SRC (set)) == PLUS
1556 && recog_data.n_operands >= 3
1557 && recog_data.operand_loc[1] == &XEXP (SET_SRC (set), 0)
1558 && recog_data.operand_loc[2] == &XEXP (SET_SRC (set), 1)
1559 && CONST_INT_P (recog_data.operand[2])
1560 && (new_rtx = instantiate_new_reg (recog_data.operand[1], &offset)))
1562 offset += INTVAL (recog_data.operand[2]);
1564 /* If the sum is zero, then replace with a plain move. */
1566 && REG_P (SET_DEST (set))
1567 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1570 emit_move_insn (SET_DEST (set), new_rtx);
1574 emit_insn_before (seq, insn);
1579 x = gen_int_mode (offset, recog_data.operand_mode[2]);
1581 /* Using validate_change and apply_change_group here leaves
1582 recog_data in an invalid state. Since we know exactly what
1583 we want to check, do those two by hand. */
1584 if (safe_insn_predicate (insn_code, 1, new_rtx)
1585 && safe_insn_predicate (insn_code, 2, x))
1587 *recog_data.operand_loc[1] = recog_data.operand[1] = new_rtx;
1588 *recog_data.operand_loc[2] = recog_data.operand[2] = x;
1591 /* Fall through into the regular operand fixup loop in
1592 order to take care of operands other than 1 and 2. */
1598 extract_insn (insn);
1599 insn_code = INSN_CODE (insn);
1602 /* In the general case, we expect virtual registers to appear only in
1603 operands, and then only as either bare registers or inside memories. */
1604 for (i = 0; i < recog_data.n_operands; ++i)
1606 x = recog_data.operand[i];
1607 switch (GET_CODE (x))
1611 rtx addr = XEXP (x, 0);
1612 bool changed = false;
1614 for_each_rtx (&addr, instantiate_virtual_regs_in_rtx, &changed);
1619 x = replace_equiv_address (x, addr);
1620 /* It may happen that the address with the virtual reg
1621 was valid (e.g. based on the virtual stack reg, which might
1622 be acceptable to the predicates with all offsets), whereas
1623 the address now isn't anymore, for instance when the address
1624 is still offsetted, but the base reg isn't virtual-stack-reg
1625 anymore. Below we would do a force_reg on the whole operand,
1626 but this insn might actually only accept memory. Hence,
1627 before doing that last resort, try to reload the address into
1628 a register, so this operand stays a MEM. */
1629 if (!safe_insn_predicate (insn_code, i, x))
1631 addr = force_reg (GET_MODE (addr), addr);
1632 x = replace_equiv_address (x, addr);
1637 emit_insn_before (seq, insn);
1642 new_rtx = instantiate_new_reg (x, &offset);
1643 if (new_rtx == NULL)
1651 /* Careful, special mode predicates may have stuff in
1652 insn_data[insn_code].operand[i].mode that isn't useful
1653 to us for computing a new value. */
1654 /* ??? Recognize address_operand and/or "p" constraints
1655 to see if (plus new offset) is a valid before we put
1656 this through expand_simple_binop. */
1657 x = expand_simple_binop (GET_MODE (x), PLUS, new_rtx,
1658 GEN_INT (offset), NULL_RTX,
1659 1, OPTAB_LIB_WIDEN);
1662 emit_insn_before (seq, insn);
1667 new_rtx = instantiate_new_reg (SUBREG_REG (x), &offset);
1668 if (new_rtx == NULL)
1673 new_rtx = expand_simple_binop (GET_MODE (new_rtx), PLUS, new_rtx,
1674 GEN_INT (offset), NULL_RTX,
1675 1, OPTAB_LIB_WIDEN);
1678 emit_insn_before (seq, insn);
1680 x = simplify_gen_subreg (recog_data.operand_mode[i], new_rtx,
1681 GET_MODE (new_rtx), SUBREG_BYTE (x));
1689 /* At this point, X contains the new value for the operand.
1690 Validate the new value vs the insn predicate. Note that
1691 asm insns will have insn_code -1 here. */
1692 if (!safe_insn_predicate (insn_code, i, x))
1697 gcc_assert (REGNO (x) <= LAST_VIRTUAL_REGISTER);
1698 x = copy_to_reg (x);
1701 x = force_reg (insn_data[insn_code].operand[i].mode, x);
1705 emit_insn_before (seq, insn);
1708 *recog_data.operand_loc[i] = recog_data.operand[i] = x;
1714 /* Propagate operand changes into the duplicates. */
1715 for (i = 0; i < recog_data.n_dups; ++i)
1716 *recog_data.dup_loc[i]
1717 = copy_rtx (recog_data.operand[(unsigned)recog_data.dup_num[i]]);
1719 /* Force re-recognition of the instruction for validation. */
1720 INSN_CODE (insn) = -1;
1723 if (asm_noperands (PATTERN (insn)) >= 0)
1725 if (!check_asm_operands (PATTERN (insn)))
1727 error_for_asm (insn, "impossible constraint in %<asm%>");
1733 if (recog_memoized (insn) < 0)
1734 fatal_insn_not_found (insn);
1738 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1739 do any instantiation required. */
1742 instantiate_decl_rtl (rtx x)
1749 /* If this is a CONCAT, recurse for the pieces. */
1750 if (GET_CODE (x) == CONCAT)
1752 instantiate_decl_rtl (XEXP (x, 0));
1753 instantiate_decl_rtl (XEXP (x, 1));
1757 /* If this is not a MEM, no need to do anything. Similarly if the
1758 address is a constant or a register that is not a virtual register. */
1763 if (CONSTANT_P (addr)
1765 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
1766 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
1769 for_each_rtx (&XEXP (x, 0), instantiate_virtual_regs_in_rtx, NULL);
1772 /* Helper for instantiate_decls called via walk_tree: Process all decls
1773 in the given DECL_VALUE_EXPR. */
1776 instantiate_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
1782 if (DECL_P (t) && DECL_RTL_SET_P (t))
1783 instantiate_decl_rtl (DECL_RTL (t));
1788 /* Subroutine of instantiate_decls: Process all decls in the given
1789 BLOCK node and all its subblocks. */
1792 instantiate_decls_1 (tree let)
1796 for (t = BLOCK_VARS (let); t; t = DECL_CHAIN (t))
1798 if (DECL_RTL_SET_P (t))
1799 instantiate_decl_rtl (DECL_RTL (t));
1800 if (TREE_CODE (t) == VAR_DECL && DECL_HAS_VALUE_EXPR_P (t))
1802 tree v = DECL_VALUE_EXPR (t);
1803 walk_tree (&v, instantiate_expr, NULL, NULL);
1807 /* Process all subblocks. */
1808 for (t = BLOCK_SUBBLOCKS (let); t; t = BLOCK_CHAIN (t))
1809 instantiate_decls_1 (t);
1812 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1813 all virtual registers in their DECL_RTL's. */
1816 instantiate_decls (tree fndecl)
1821 /* Process all parameters of the function. */
1822 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = DECL_CHAIN (decl))
1824 instantiate_decl_rtl (DECL_RTL (decl));
1825 instantiate_decl_rtl (DECL_INCOMING_RTL (decl));
1826 if (DECL_HAS_VALUE_EXPR_P (decl))
1828 tree v = DECL_VALUE_EXPR (decl);
1829 walk_tree (&v, instantiate_expr, NULL, NULL);
1833 /* Now process all variables defined in the function or its subblocks. */
1834 instantiate_decls_1 (DECL_INITIAL (fndecl));
1836 FOR_EACH_LOCAL_DECL (cfun, ix, decl)
1837 if (DECL_RTL_SET_P (decl))
1838 instantiate_decl_rtl (DECL_RTL (decl));
1839 VEC_free (tree, gc, cfun->local_decls);
1842 /* Pass through the INSNS of function FNDECL and convert virtual register
1843 references to hard register references. */
1846 instantiate_virtual_regs (void)
1850 /* Compute the offsets to use for this function. */
1851 in_arg_offset = FIRST_PARM_OFFSET (current_function_decl);
1852 var_offset = STARTING_FRAME_OFFSET;
1853 dynamic_offset = STACK_DYNAMIC_OFFSET (current_function_decl);
1854 out_arg_offset = STACK_POINTER_OFFSET;
1855 #ifdef FRAME_POINTER_CFA_OFFSET
1856 cfa_offset = FRAME_POINTER_CFA_OFFSET (current_function_decl);
1858 cfa_offset = ARG_POINTER_CFA_OFFSET (current_function_decl);
1861 /* Initialize recognition, indicating that volatile is OK. */
1864 /* Scan through all the insns, instantiating every virtual register still
1866 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
1869 /* These patterns in the instruction stream can never be recognized.
1870 Fortunately, they shouldn't contain virtual registers either. */
1871 if (GET_CODE (PATTERN (insn)) == USE
1872 || GET_CODE (PATTERN (insn)) == CLOBBER
1873 || GET_CODE (PATTERN (insn)) == ADDR_VEC
1874 || GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC
1875 || GET_CODE (PATTERN (insn)) == ASM_INPUT)
1877 else if (DEBUG_INSN_P (insn))
1878 for_each_rtx (&INSN_VAR_LOCATION (insn),
1879 instantiate_virtual_regs_in_rtx, NULL);
1881 instantiate_virtual_regs_in_insn (insn);
1883 if (INSN_DELETED_P (insn))
1886 for_each_rtx (®_NOTES (insn), instantiate_virtual_regs_in_rtx, NULL);
1888 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1890 for_each_rtx (&CALL_INSN_FUNCTION_USAGE (insn),
1891 instantiate_virtual_regs_in_rtx, NULL);
1894 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1895 instantiate_decls (current_function_decl);
1897 targetm.instantiate_decls ();
1899 /* Indicate that, from now on, assign_stack_local should use
1900 frame_pointer_rtx. */
1901 virtuals_instantiated = 1;
1905 struct rtl_opt_pass pass_instantiate_virtual_regs =
1911 instantiate_virtual_regs, /* execute */
1914 0, /* static_pass_number */
1915 TV_NONE, /* tv_id */
1916 0, /* properties_required */
1917 0, /* properties_provided */
1918 0, /* properties_destroyed */
1919 0, /* todo_flags_start */
1920 TODO_dump_func /* todo_flags_finish */
1925 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
1926 This means a type for which function calls must pass an address to the
1927 function or get an address back from the function.
1928 EXP may be a type node or an expression (whose type is tested). */
1931 aggregate_value_p (const_tree exp, const_tree fntype)
1933 const_tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
1934 int i, regno, nregs;
1938 switch (TREE_CODE (fntype))
1942 tree fndecl = get_callee_fndecl (fntype);
1944 ? TREE_TYPE (fndecl)
1945 : TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (fntype))));
1949 fntype = TREE_TYPE (fntype);
1954 case IDENTIFIER_NODE:
1958 /* We don't expect other tree types here. */
1962 if (VOID_TYPE_P (type))
1965 /* If a record should be passed the same as its first (and only) member
1966 don't pass it as an aggregate. */
1967 if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
1968 return aggregate_value_p (first_field (type), fntype);
1970 /* If the front end has decided that this needs to be passed by
1971 reference, do so. */
1972 if ((TREE_CODE (exp) == PARM_DECL || TREE_CODE (exp) == RESULT_DECL)
1973 && DECL_BY_REFERENCE (exp))
1976 /* Function types that are TREE_ADDRESSABLE force return in memory. */
1977 if (fntype && TREE_ADDRESSABLE (fntype))
1980 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
1981 and thus can't be returned in registers. */
1982 if (TREE_ADDRESSABLE (type))
1985 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
1988 if (targetm.calls.return_in_memory (type, fntype))
1991 /* Make sure we have suitable call-clobbered regs to return
1992 the value in; if not, we must return it in memory. */
1993 reg = hard_function_value (type, 0, fntype, 0);
1995 /* If we have something other than a REG (e.g. a PARALLEL), then assume
2000 regno = REGNO (reg);
2001 nregs = hard_regno_nregs[regno][TYPE_MODE (type)];
2002 for (i = 0; i < nregs; i++)
2003 if (! call_used_regs[regno + i])
2009 /* Return true if we should assign DECL a pseudo register; false if it
2010 should live on the local stack. */
2013 use_register_for_decl (const_tree decl)
2015 if (!targetm.calls.allocate_stack_slots_for_args())
2018 /* Honor volatile. */
2019 if (TREE_SIDE_EFFECTS (decl))
2022 /* Honor addressability. */
2023 if (TREE_ADDRESSABLE (decl))
2026 /* Only register-like things go in registers. */
2027 if (DECL_MODE (decl) == BLKmode)
2030 /* If -ffloat-store specified, don't put explicit float variables
2032 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
2033 propagates values across these stores, and it probably shouldn't. */
2034 if (flag_float_store && FLOAT_TYPE_P (TREE_TYPE (decl)))
2037 /* If we're not interested in tracking debugging information for
2038 this decl, then we can certainly put it in a register. */
2039 if (DECL_IGNORED_P (decl))
2045 if (!DECL_REGISTER (decl))
2048 switch (TREE_CODE (TREE_TYPE (decl)))
2052 case QUAL_UNION_TYPE:
2053 /* When not optimizing, disregard register keyword for variables with
2054 types containing methods, otherwise the methods won't be callable
2055 from the debugger. */
2056 if (TYPE_METHODS (TREE_TYPE (decl)))
2066 /* Return true if TYPE should be passed by invisible reference. */
2069 pass_by_reference (CUMULATIVE_ARGS *ca, enum machine_mode mode,
2070 tree type, bool named_arg)
2074 /* If this type contains non-trivial constructors, then it is
2075 forbidden for the middle-end to create any new copies. */
2076 if (TREE_ADDRESSABLE (type))
2079 /* GCC post 3.4 passes *all* variable sized types by reference. */
2080 if (!TYPE_SIZE (type) || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
2083 /* If a record type should be passed the same as its first (and only)
2084 member, use the type and mode of that member. */
2085 if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
2087 type = TREE_TYPE (first_field (type));
2088 mode = TYPE_MODE (type);
2092 return targetm.calls.pass_by_reference (ca, mode, type, named_arg);
2095 /* Return true if TYPE, which is passed by reference, should be callee
2096 copied instead of caller copied. */
2099 reference_callee_copied (CUMULATIVE_ARGS *ca, enum machine_mode mode,
2100 tree type, bool named_arg)
2102 if (type && TREE_ADDRESSABLE (type))
2104 return targetm.calls.callee_copies (ca, mode, type, named_arg);
2107 /* Structures to communicate between the subroutines of assign_parms.
2108 The first holds data persistent across all parameters, the second
2109 is cleared out for each parameter. */
2111 struct assign_parm_data_all
2113 CUMULATIVE_ARGS args_so_far;
2114 struct args_size stack_args_size;
2115 tree function_result_decl;
2117 rtx first_conversion_insn;
2118 rtx last_conversion_insn;
2119 HOST_WIDE_INT pretend_args_size;
2120 HOST_WIDE_INT extra_pretend_bytes;
2121 int reg_parm_stack_space;
2124 struct assign_parm_data_one
2130 enum machine_mode nominal_mode;
2131 enum machine_mode passed_mode;
2132 enum machine_mode promoted_mode;
2133 struct locate_and_pad_arg_data locate;
2135 BOOL_BITFIELD named_arg : 1;
2136 BOOL_BITFIELD passed_pointer : 1;
2137 BOOL_BITFIELD on_stack : 1;
2138 BOOL_BITFIELD loaded_in_reg : 1;
2141 /* A subroutine of assign_parms. Initialize ALL. */
2144 assign_parms_initialize_all (struct assign_parm_data_all *all)
2146 tree fntype ATTRIBUTE_UNUSED;
2148 memset (all, 0, sizeof (*all));
2150 fntype = TREE_TYPE (current_function_decl);
2152 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
2153 INIT_CUMULATIVE_INCOMING_ARGS (all->args_so_far, fntype, NULL_RTX);
2155 INIT_CUMULATIVE_ARGS (all->args_so_far, fntype, NULL_RTX,
2156 current_function_decl, -1);
2159 #ifdef REG_PARM_STACK_SPACE
2160 all->reg_parm_stack_space = REG_PARM_STACK_SPACE (current_function_decl);
2164 /* If ARGS contains entries with complex types, split the entry into two
2165 entries of the component type. Return a new list of substitutions are
2166 needed, else the old list. */
2169 split_complex_args (VEC(tree, heap) **args)
2174 for (i = 0; VEC_iterate (tree, *args, i, p); ++i)
2176 tree type = TREE_TYPE (p);
2177 if (TREE_CODE (type) == COMPLEX_TYPE
2178 && targetm.calls.split_complex_arg (type))
2181 tree subtype = TREE_TYPE (type);
2182 bool addressable = TREE_ADDRESSABLE (p);
2184 /* Rewrite the PARM_DECL's type with its component. */
2186 TREE_TYPE (p) = subtype;
2187 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
2188 DECL_MODE (p) = VOIDmode;
2189 DECL_SIZE (p) = NULL;
2190 DECL_SIZE_UNIT (p) = NULL;
2191 /* If this arg must go in memory, put it in a pseudo here.
2192 We can't allow it to go in memory as per normal parms,
2193 because the usual place might not have the imag part
2194 adjacent to the real part. */
2195 DECL_ARTIFICIAL (p) = addressable;
2196 DECL_IGNORED_P (p) = addressable;
2197 TREE_ADDRESSABLE (p) = 0;
2199 VEC_replace (tree, *args, i, p);
2201 /* Build a second synthetic decl. */
2202 decl = build_decl (EXPR_LOCATION (p),
2203 PARM_DECL, NULL_TREE, subtype);
2204 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
2205 DECL_ARTIFICIAL (decl) = addressable;
2206 DECL_IGNORED_P (decl) = addressable;
2207 layout_decl (decl, 0);
2208 VEC_safe_insert (tree, heap, *args, ++i, decl);
2213 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
2214 the hidden struct return argument, and (abi willing) complex args.
2215 Return the new parameter list. */
2217 static VEC(tree, heap) *
2218 assign_parms_augmented_arg_list (struct assign_parm_data_all *all)
2220 tree fndecl = current_function_decl;
2221 tree fntype = TREE_TYPE (fndecl);
2222 VEC(tree, heap) *fnargs = NULL;
2225 for (arg = DECL_ARGUMENTS (fndecl); arg; arg = DECL_CHAIN (arg))
2226 VEC_safe_push (tree, heap, fnargs, arg);
2228 all->orig_fnargs = DECL_ARGUMENTS (fndecl);
2230 /* If struct value address is treated as the first argument, make it so. */
2231 if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
2232 && ! cfun->returns_pcc_struct
2233 && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
2235 tree type = build_pointer_type (TREE_TYPE (fntype));
2238 decl = build_decl (DECL_SOURCE_LOCATION (fndecl),
2239 PARM_DECL, NULL_TREE, type);
2240 DECL_ARG_TYPE (decl) = type;
2241 DECL_ARTIFICIAL (decl) = 1;
2242 DECL_IGNORED_P (decl) = 1;
2244 DECL_CHAIN (decl) = all->orig_fnargs;
2245 all->orig_fnargs = decl;
2246 VEC_safe_insert (tree, heap, fnargs, 0, decl);
2248 all->function_result_decl = decl;
2251 /* If the target wants to split complex arguments into scalars, do so. */
2252 if (targetm.calls.split_complex_arg)
2253 split_complex_args (&fnargs);
2258 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2259 data for the parameter. Incorporate ABI specifics such as pass-by-
2260 reference and type promotion. */
2263 assign_parm_find_data_types (struct assign_parm_data_all *all, tree parm,
2264 struct assign_parm_data_one *data)
2266 tree nominal_type, passed_type;
2267 enum machine_mode nominal_mode, passed_mode, promoted_mode;
2270 memset (data, 0, sizeof (*data));
2272 /* NAMED_ARG is a misnomer. We really mean 'non-variadic'. */
2274 data->named_arg = 1; /* No variadic parms. */
2275 else if (DECL_CHAIN (parm))
2276 data->named_arg = 1; /* Not the last non-variadic parm. */
2277 else if (targetm.calls.strict_argument_naming (&all->args_so_far))
2278 data->named_arg = 1; /* Only variadic ones are unnamed. */
2280 data->named_arg = 0; /* Treat as variadic. */
2282 nominal_type = TREE_TYPE (parm);
2283 passed_type = DECL_ARG_TYPE (parm);
2285 /* Look out for errors propagating this far. Also, if the parameter's
2286 type is void then its value doesn't matter. */
2287 if (TREE_TYPE (parm) == error_mark_node
2288 /* This can happen after weird syntax errors
2289 or if an enum type is defined among the parms. */
2290 || TREE_CODE (parm) != PARM_DECL
2291 || passed_type == NULL
2292 || VOID_TYPE_P (nominal_type))
2294 nominal_type = passed_type = void_type_node;
2295 nominal_mode = passed_mode = promoted_mode = VOIDmode;
2299 /* Find mode of arg as it is passed, and mode of arg as it should be
2300 during execution of this function. */
2301 passed_mode = TYPE_MODE (passed_type);
2302 nominal_mode = TYPE_MODE (nominal_type);
2304 /* If the parm is to be passed as a transparent union or record, use the
2305 type of the first field for the tests below. We have already verified
2306 that the modes are the same. */
2307 if ((TREE_CODE (passed_type) == UNION_TYPE
2308 || TREE_CODE (passed_type) == RECORD_TYPE)
2309 && TYPE_TRANSPARENT_AGGR (passed_type))
2310 passed_type = TREE_TYPE (first_field (passed_type));
2312 /* See if this arg was passed by invisible reference. */
2313 if (pass_by_reference (&all->args_so_far, passed_mode,
2314 passed_type, data->named_arg))
2316 passed_type = nominal_type = build_pointer_type (passed_type);
2317 data->passed_pointer = true;
2318 passed_mode = nominal_mode = Pmode;
2321 /* Find mode as it is passed by the ABI. */
2322 unsignedp = TYPE_UNSIGNED (passed_type);
2323 promoted_mode = promote_function_mode (passed_type, passed_mode, &unsignedp,
2324 TREE_TYPE (current_function_decl), 0);
2327 data->nominal_type = nominal_type;
2328 data->passed_type = passed_type;
2329 data->nominal_mode = nominal_mode;
2330 data->passed_mode = passed_mode;
2331 data->promoted_mode = promoted_mode;
2334 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2337 assign_parms_setup_varargs (struct assign_parm_data_all *all,
2338 struct assign_parm_data_one *data, bool no_rtl)
2340 int varargs_pretend_bytes = 0;
2342 targetm.calls.setup_incoming_varargs (&all->args_so_far,
2343 data->promoted_mode,
2345 &varargs_pretend_bytes, no_rtl);
2347 /* If the back-end has requested extra stack space, record how much is
2348 needed. Do not change pretend_args_size otherwise since it may be
2349 nonzero from an earlier partial argument. */
2350 if (varargs_pretend_bytes > 0)
2351 all->pretend_args_size = varargs_pretend_bytes;
2354 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2355 the incoming location of the current parameter. */
2358 assign_parm_find_entry_rtl (struct assign_parm_data_all *all,
2359 struct assign_parm_data_one *data)
2361 HOST_WIDE_INT pretend_bytes = 0;
2365 if (data->promoted_mode == VOIDmode)
2367 data->entry_parm = data->stack_parm = const0_rtx;
2371 entry_parm = targetm.calls.function_incoming_arg (&all->args_so_far,
2372 data->promoted_mode,
2376 if (entry_parm == 0)
2377 data->promoted_mode = data->passed_mode;
2379 /* Determine parm's home in the stack, in case it arrives in the stack
2380 or we should pretend it did. Compute the stack position and rtx where
2381 the argument arrives and its size.
2383 There is one complexity here: If this was a parameter that would
2384 have been passed in registers, but wasn't only because it is
2385 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2386 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2387 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2388 as it was the previous time. */
2389 in_regs = entry_parm != 0;
2390 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2393 if (!in_regs && !data->named_arg)
2395 if (targetm.calls.pretend_outgoing_varargs_named (&all->args_so_far))
2398 tem = targetm.calls.function_incoming_arg (&all->args_so_far,
2399 data->promoted_mode,
2400 data->passed_type, true);
2401 in_regs = tem != NULL;
2405 /* If this parameter was passed both in registers and in the stack, use
2406 the copy on the stack. */
2407 if (targetm.calls.must_pass_in_stack (data->promoted_mode,
2415 partial = targetm.calls.arg_partial_bytes (&all->args_so_far,
2416 data->promoted_mode,
2419 data->partial = partial;
2421 /* The caller might already have allocated stack space for the
2422 register parameters. */
2423 if (partial != 0 && all->reg_parm_stack_space == 0)
2425 /* Part of this argument is passed in registers and part
2426 is passed on the stack. Ask the prologue code to extend
2427 the stack part so that we can recreate the full value.
2429 PRETEND_BYTES is the size of the registers we need to store.
2430 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2431 stack space that the prologue should allocate.
2433 Internally, gcc assumes that the argument pointer is aligned
2434 to STACK_BOUNDARY bits. This is used both for alignment
2435 optimizations (see init_emit) and to locate arguments that are
2436 aligned to more than PARM_BOUNDARY bits. We must preserve this
2437 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2438 a stack boundary. */
2440 /* We assume at most one partial arg, and it must be the first
2441 argument on the stack. */
2442 gcc_assert (!all->extra_pretend_bytes && !all->pretend_args_size);
2444 pretend_bytes = partial;
2445 all->pretend_args_size = CEIL_ROUND (pretend_bytes, STACK_BYTES);
2447 /* We want to align relative to the actual stack pointer, so
2448 don't include this in the stack size until later. */
2449 all->extra_pretend_bytes = all->pretend_args_size;
2453 locate_and_pad_parm (data->promoted_mode, data->passed_type, in_regs,
2454 entry_parm ? data->partial : 0, current_function_decl,
2455 &all->stack_args_size, &data->locate);
2457 /* Update parm_stack_boundary if this parameter is passed in the
2459 if (!in_regs && crtl->parm_stack_boundary < data->locate.boundary)
2460 crtl->parm_stack_boundary = data->locate.boundary;
2462 /* Adjust offsets to include the pretend args. */
2463 pretend_bytes = all->extra_pretend_bytes - pretend_bytes;
2464 data->locate.slot_offset.constant += pretend_bytes;
2465 data->locate.offset.constant += pretend_bytes;
2467 data->entry_parm = entry_parm;
2470 /* A subroutine of assign_parms. If there is actually space on the stack
2471 for this parm, count it in stack_args_size and return true. */
2474 assign_parm_is_stack_parm (struct assign_parm_data_all *all,
2475 struct assign_parm_data_one *data)
2477 /* Trivially true if we've no incoming register. */
2478 if (data->entry_parm == NULL)
2480 /* Also true if we're partially in registers and partially not,
2481 since we've arranged to drop the entire argument on the stack. */
2482 else if (data->partial != 0)
2484 /* Also true if the target says that it's passed in both registers
2485 and on the stack. */
2486 else if (GET_CODE (data->entry_parm) == PARALLEL
2487 && XEXP (XVECEXP (data->entry_parm, 0, 0), 0) == NULL_RTX)
2489 /* Also true if the target says that there's stack allocated for
2490 all register parameters. */
2491 else if (all->reg_parm_stack_space > 0)
2493 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2497 all->stack_args_size.constant += data->locate.size.constant;
2498 if (data->locate.size.var)
2499 ADD_PARM_SIZE (all->stack_args_size, data->locate.size.var);
2504 /* A subroutine of assign_parms. Given that this parameter is allocated
2505 stack space by the ABI, find it. */
2508 assign_parm_find_stack_rtl (tree parm, struct assign_parm_data_one *data)
2510 rtx offset_rtx, stack_parm;
2511 unsigned int align, boundary;
2513 /* If we're passing this arg using a reg, make its stack home the
2514 aligned stack slot. */
2515 if (data->entry_parm)
2516 offset_rtx = ARGS_SIZE_RTX (data->locate.slot_offset);
2518 offset_rtx = ARGS_SIZE_RTX (data->locate.offset);
2520 stack_parm = crtl->args.internal_arg_pointer;
2521 if (offset_rtx != const0_rtx)
2522 stack_parm = gen_rtx_PLUS (Pmode, stack_parm, offset_rtx);
2523 stack_parm = gen_rtx_MEM (data->promoted_mode, stack_parm);
2525 if (!data->passed_pointer)
2527 set_mem_attributes (stack_parm, parm, 1);
2528 /* set_mem_attributes could set MEM_SIZE to the passed mode's size,
2529 while promoted mode's size is needed. */
2530 if (data->promoted_mode != BLKmode
2531 && data->promoted_mode != DECL_MODE (parm))
2533 set_mem_size (stack_parm,
2534 GEN_INT (GET_MODE_SIZE (data->promoted_mode)));
2535 if (MEM_EXPR (stack_parm) && MEM_OFFSET (stack_parm))
2537 int offset = subreg_lowpart_offset (DECL_MODE (parm),
2538 data->promoted_mode);
2540 set_mem_offset (stack_parm,
2541 plus_constant (MEM_OFFSET (stack_parm),
2547 boundary = data->locate.boundary;
2548 align = BITS_PER_UNIT;
2550 /* If we're padding upward, we know that the alignment of the slot
2551 is FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2552 intentionally forcing upward padding. Otherwise we have to come
2553 up with a guess at the alignment based on OFFSET_RTX. */
2554 if (data->locate.where_pad != downward || data->entry_parm)
2556 else if (CONST_INT_P (offset_rtx))
2558 align = INTVAL (offset_rtx) * BITS_PER_UNIT | boundary;
2559 align = align & -align;
2561 set_mem_align (stack_parm, align);
2563 if (data->entry_parm)
2564 set_reg_attrs_for_parm (data->entry_parm, stack_parm);
2566 data->stack_parm = stack_parm;
2569 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2570 always valid and contiguous. */
2573 assign_parm_adjust_entry_rtl (struct assign_parm_data_one *data)
2575 rtx entry_parm = data->entry_parm;
2576 rtx stack_parm = data->stack_parm;
2578 /* If this parm was passed part in regs and part in memory, pretend it
2579 arrived entirely in memory by pushing the register-part onto the stack.
2580 In the special case of a DImode or DFmode that is split, we could put
2581 it together in a pseudoreg directly, but for now that's not worth
2583 if (data->partial != 0)
2585 /* Handle calls that pass values in multiple non-contiguous
2586 locations. The Irix 6 ABI has examples of this. */
2587 if (GET_CODE (entry_parm) == PARALLEL)
2588 emit_group_store (validize_mem (stack_parm), entry_parm,
2590 int_size_in_bytes (data->passed_type));
2593 gcc_assert (data->partial % UNITS_PER_WORD == 0);
2594 move_block_from_reg (REGNO (entry_parm), validize_mem (stack_parm),
2595 data->partial / UNITS_PER_WORD);
2598 entry_parm = stack_parm;
2601 /* If we didn't decide this parm came in a register, by default it came
2603 else if (entry_parm == NULL)
2604 entry_parm = stack_parm;
2606 /* When an argument is passed in multiple locations, we can't make use
2607 of this information, but we can save some copying if the whole argument
2608 is passed in a single register. */
2609 else if (GET_CODE (entry_parm) == PARALLEL
2610 && data->nominal_mode != BLKmode
2611 && data->passed_mode != BLKmode)
2613 size_t i, len = XVECLEN (entry_parm, 0);
2615 for (i = 0; i < len; i++)
2616 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
2617 && REG_P (XEXP (XVECEXP (entry_parm, 0, i), 0))
2618 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
2619 == data->passed_mode)
2620 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
2622 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
2627 data->entry_parm = entry_parm;
2630 /* A subroutine of assign_parms. Reconstitute any values which were
2631 passed in multiple registers and would fit in a single register. */
2634 assign_parm_remove_parallels (struct assign_parm_data_one *data)
2636 rtx entry_parm = data->entry_parm;
2638 /* Convert the PARALLEL to a REG of the same mode as the parallel.
2639 This can be done with register operations rather than on the
2640 stack, even if we will store the reconstituted parameter on the
2642 if (GET_CODE (entry_parm) == PARALLEL && GET_MODE (entry_parm) != BLKmode)
2644 rtx parmreg = gen_reg_rtx (GET_MODE (entry_parm));
2645 emit_group_store (parmreg, entry_parm, data->passed_type,
2646 GET_MODE_SIZE (GET_MODE (entry_parm)));
2647 entry_parm = parmreg;
2650 data->entry_parm = entry_parm;
2653 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2654 always valid and properly aligned. */
2657 assign_parm_adjust_stack_rtl (struct assign_parm_data_one *data)
2659 rtx stack_parm = data->stack_parm;
2661 /* If we can't trust the parm stack slot to be aligned enough for its
2662 ultimate type, don't use that slot after entry. We'll make another
2663 stack slot, if we need one. */
2665 && ((STRICT_ALIGNMENT
2666 && GET_MODE_ALIGNMENT (data->nominal_mode) > MEM_ALIGN (stack_parm))
2667 || (data->nominal_type
2668 && TYPE_ALIGN (data->nominal_type) > MEM_ALIGN (stack_parm)
2669 && MEM_ALIGN (stack_parm) < PREFERRED_STACK_BOUNDARY)))
2672 /* If parm was passed in memory, and we need to convert it on entry,
2673 don't store it back in that same slot. */
2674 else if (data->entry_parm == stack_parm
2675 && data->nominal_mode != BLKmode
2676 && data->nominal_mode != data->passed_mode)
2679 /* If stack protection is in effect for this function, don't leave any
2680 pointers in their passed stack slots. */
2681 else if (crtl->stack_protect_guard
2682 && (flag_stack_protect == 2
2683 || data->passed_pointer
2684 || POINTER_TYPE_P (data->nominal_type)))
2687 data->stack_parm = stack_parm;
2690 /* A subroutine of assign_parms. Return true if the current parameter
2691 should be stored as a BLKmode in the current frame. */
2694 assign_parm_setup_block_p (struct assign_parm_data_one *data)
2696 if (data->nominal_mode == BLKmode)
2698 if (GET_MODE (data->entry_parm) == BLKmode)
2701 #ifdef BLOCK_REG_PADDING
2702 /* Only assign_parm_setup_block knows how to deal with register arguments
2703 that are padded at the least significant end. */
2704 if (REG_P (data->entry_parm)
2705 && GET_MODE_SIZE (data->promoted_mode) < UNITS_PER_WORD
2706 && (BLOCK_REG_PADDING (data->passed_mode, data->passed_type, 1)
2707 == (BYTES_BIG_ENDIAN ? upward : downward)))
2714 /* A subroutine of assign_parms. Arrange for the parameter to be
2715 present and valid in DATA->STACK_RTL. */
2718 assign_parm_setup_block (struct assign_parm_data_all *all,
2719 tree parm, struct assign_parm_data_one *data)
2721 rtx entry_parm = data->entry_parm;
2722 rtx stack_parm = data->stack_parm;
2724 HOST_WIDE_INT size_stored;
2726 if (GET_CODE (entry_parm) == PARALLEL)
2727 entry_parm = emit_group_move_into_temps (entry_parm);
2729 size = int_size_in_bytes (data->passed_type);
2730 size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
2731 if (stack_parm == 0)
2733 DECL_ALIGN (parm) = MAX (DECL_ALIGN (parm), BITS_PER_WORD);
2734 stack_parm = assign_stack_local (BLKmode, size_stored,
2736 if (GET_MODE_SIZE (GET_MODE (entry_parm)) == size)
2737 PUT_MODE (stack_parm, GET_MODE (entry_parm));
2738 set_mem_attributes (stack_parm, parm, 1);
2741 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2742 calls that pass values in multiple non-contiguous locations. */
2743 if (REG_P (entry_parm) || GET_CODE (entry_parm) == PARALLEL)
2747 /* Note that we will be storing an integral number of words.
2748 So we have to be careful to ensure that we allocate an
2749 integral number of words. We do this above when we call
2750 assign_stack_local if space was not allocated in the argument
2751 list. If it was, this will not work if PARM_BOUNDARY is not
2752 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2753 if it becomes a problem. Exception is when BLKmode arrives
2754 with arguments not conforming to word_mode. */
2756 if (data->stack_parm == 0)
2758 else if (GET_CODE (entry_parm) == PARALLEL)
2761 gcc_assert (!size || !(PARM_BOUNDARY % BITS_PER_WORD));
2763 mem = validize_mem (stack_parm);
2765 /* Handle values in multiple non-contiguous locations. */
2766 if (GET_CODE (entry_parm) == PARALLEL)
2768 push_to_sequence2 (all->first_conversion_insn,
2769 all->last_conversion_insn);
2770 emit_group_store (mem, entry_parm, data->passed_type, size);
2771 all->first_conversion_insn = get_insns ();
2772 all->last_conversion_insn = get_last_insn ();
2779 /* If SIZE is that of a mode no bigger than a word, just use
2780 that mode's store operation. */
2781 else if (size <= UNITS_PER_WORD)
2783 enum machine_mode mode
2784 = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
2787 #ifdef BLOCK_REG_PADDING
2788 && (size == UNITS_PER_WORD
2789 || (BLOCK_REG_PADDING (mode, data->passed_type, 1)
2790 != (BYTES_BIG_ENDIAN ? upward : downward)))
2796 /* We are really truncating a word_mode value containing
2797 SIZE bytes into a value of mode MODE. If such an
2798 operation requires no actual instructions, we can refer
2799 to the value directly in mode MODE, otherwise we must
2800 start with the register in word_mode and explicitly
2802 if (TRULY_NOOP_TRUNCATION (size * BITS_PER_UNIT, BITS_PER_WORD))
2803 reg = gen_rtx_REG (mode, REGNO (entry_parm));
2806 reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
2807 reg = convert_to_mode (mode, copy_to_reg (reg), 1);
2809 emit_move_insn (change_address (mem, mode, 0), reg);
2812 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
2813 machine must be aligned to the left before storing
2814 to memory. Note that the previous test doesn't
2815 handle all cases (e.g. SIZE == 3). */
2816 else if (size != UNITS_PER_WORD
2817 #ifdef BLOCK_REG_PADDING
2818 && (BLOCK_REG_PADDING (mode, data->passed_type, 1)
2826 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2827 rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
2829 x = expand_shift (LSHIFT_EXPR, word_mode, reg,
2830 build_int_cst (NULL_TREE, by),
2832 tem = change_address (mem, word_mode, 0);
2833 emit_move_insn (tem, x);
2836 move_block_from_reg (REGNO (entry_parm), mem,
2837 size_stored / UNITS_PER_WORD);
2840 move_block_from_reg (REGNO (entry_parm), mem,
2841 size_stored / UNITS_PER_WORD);
2843 else if (data->stack_parm == 0)
2845 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
2846 emit_block_move (stack_parm, data->entry_parm, GEN_INT (size),
2848 all->first_conversion_insn = get_insns ();
2849 all->last_conversion_insn = get_last_insn ();
2853 data->stack_parm = stack_parm;
2854 SET_DECL_RTL (parm, stack_parm);
2857 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
2858 parameter. Get it there. Perform all ABI specified conversions. */
2861 assign_parm_setup_reg (struct assign_parm_data_all *all, tree parm,
2862 struct assign_parm_data_one *data)
2865 enum machine_mode promoted_nominal_mode;
2866 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (parm));
2867 bool did_conversion = false;
2869 /* Store the parm in a pseudoregister during the function, but we may
2870 need to do it in a wider mode. Using 2 here makes the result
2871 consistent with promote_decl_mode and thus expand_expr_real_1. */
2872 promoted_nominal_mode
2873 = promote_function_mode (data->nominal_type, data->nominal_mode, &unsignedp,
2874 TREE_TYPE (current_function_decl), 2);
2876 parmreg = gen_reg_rtx (promoted_nominal_mode);
2878 if (!DECL_ARTIFICIAL (parm))
2879 mark_user_reg (parmreg);
2881 /* If this was an item that we received a pointer to,
2882 set DECL_RTL appropriately. */
2883 if (data->passed_pointer)
2885 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data->passed_type)), parmreg);
2886 set_mem_attributes (x, parm, 1);
2887 SET_DECL_RTL (parm, x);
2890 SET_DECL_RTL (parm, parmreg);
2892 assign_parm_remove_parallels (data);
2894 /* Copy the value into the register, thus bridging between
2895 assign_parm_find_data_types and expand_expr_real_1. */
2896 if (data->nominal_mode != data->passed_mode
2897 || promoted_nominal_mode != data->promoted_mode)
2901 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
2902 mode, by the caller. We now have to convert it to
2903 NOMINAL_MODE, if different. However, PARMREG may be in
2904 a different mode than NOMINAL_MODE if it is being stored
2907 If ENTRY_PARM is a hard register, it might be in a register
2908 not valid for operating in its mode (e.g., an odd-numbered
2909 register for a DFmode). In that case, moves are the only
2910 thing valid, so we can't do a convert from there. This
2911 occurs when the calling sequence allow such misaligned
2914 In addition, the conversion may involve a call, which could
2915 clobber parameters which haven't been copied to pseudo
2916 registers yet. Therefore, we must first copy the parm to
2917 a pseudo reg here, and save the conversion until after all
2918 parameters have been moved. */
2920 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
2922 emit_move_insn (tempreg, validize_mem (data->entry_parm));
2924 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
2925 tempreg = convert_to_mode (data->nominal_mode, tempreg, unsignedp);
2927 if (GET_CODE (tempreg) == SUBREG
2928 && GET_MODE (tempreg) == data->nominal_mode
2929 && REG_P (SUBREG_REG (tempreg))
2930 && data->nominal_mode == data->passed_mode
2931 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (data->entry_parm)
2932 && GET_MODE_SIZE (GET_MODE (tempreg))
2933 < GET_MODE_SIZE (GET_MODE (data->entry_parm)))
2935 /* The argument is already sign/zero extended, so note it
2937 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
2938 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
2941 /* TREE_USED gets set erroneously during expand_assignment. */
2942 save_tree_used = TREE_USED (parm);
2943 expand_assignment (parm, make_tree (data->nominal_type, tempreg), false);
2944 TREE_USED (parm) = save_tree_used;
2945 all->first_conversion_insn = get_insns ();
2946 all->last_conversion_insn = get_last_insn ();
2949 did_conversion = true;
2952 emit_move_insn (parmreg, validize_mem (data->entry_parm));
2954 /* If we were passed a pointer but the actual value can safely live
2955 in a register, put it in one. */
2956 if (data->passed_pointer
2957 && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
2958 /* If by-reference argument was promoted, demote it. */
2959 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
2960 || use_register_for_decl (parm)))
2962 /* We can't use nominal_mode, because it will have been set to
2963 Pmode above. We must use the actual mode of the parm. */
2964 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
2965 mark_user_reg (parmreg);
2967 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
2969 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
2970 int unsigned_p = TYPE_UNSIGNED (TREE_TYPE (parm));
2972 push_to_sequence2 (all->first_conversion_insn,
2973 all->last_conversion_insn);
2974 emit_move_insn (tempreg, DECL_RTL (parm));
2975 tempreg = convert_to_mode (GET_MODE (parmreg), tempreg, unsigned_p);
2976 emit_move_insn (parmreg, tempreg);
2977 all->first_conversion_insn = get_insns ();
2978 all->last_conversion_insn = get_last_insn ();
2981 did_conversion = true;
2984 emit_move_insn (parmreg, DECL_RTL (parm));
2986 SET_DECL_RTL (parm, parmreg);
2988 /* STACK_PARM is the pointer, not the parm, and PARMREG is
2990 data->stack_parm = NULL;
2993 /* Mark the register as eliminable if we did no conversion and it was
2994 copied from memory at a fixed offset, and the arg pointer was not
2995 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
2996 offset formed an invalid address, such memory-equivalences as we
2997 make here would screw up life analysis for it. */
2998 if (data->nominal_mode == data->passed_mode
3000 && data->stack_parm != 0
3001 && MEM_P (data->stack_parm)
3002 && data->locate.offset.var == 0
3003 && reg_mentioned_p (virtual_incoming_args_rtx,
3004 XEXP (data->stack_parm, 0)))
3006 rtx linsn = get_last_insn ();
3009 /* Mark complex types separately. */
3010 if (GET_CODE (parmreg) == CONCAT)
3012 enum machine_mode submode
3013 = GET_MODE_INNER (GET_MODE (parmreg));
3014 int regnor = REGNO (XEXP (parmreg, 0));
3015 int regnoi = REGNO (XEXP (parmreg, 1));
3016 rtx stackr = adjust_address_nv (data->stack_parm, submode, 0);
3017 rtx stacki = adjust_address_nv (data->stack_parm, submode,
3018 GET_MODE_SIZE (submode));
3020 /* Scan backwards for the set of the real and
3022 for (sinsn = linsn; sinsn != 0;
3023 sinsn = prev_nonnote_insn (sinsn))
3025 set = single_set (sinsn);
3029 if (SET_DEST (set) == regno_reg_rtx [regnoi])
3030 set_unique_reg_note (sinsn, REG_EQUIV, stacki);
3031 else if (SET_DEST (set) == regno_reg_rtx [regnor])
3032 set_unique_reg_note (sinsn, REG_EQUIV, stackr);
3035 else if ((set = single_set (linsn)) != 0
3036 && SET_DEST (set) == parmreg)
3037 set_unique_reg_note (linsn, REG_EQUIV, data->stack_parm);
3040 /* For pointer data type, suggest pointer register. */
3041 if (POINTER_TYPE_P (TREE_TYPE (parm)))
3042 mark_reg_pointer (parmreg,
3043 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
3046 /* A subroutine of assign_parms. Allocate stack space to hold the current
3047 parameter. Get it there. Perform all ABI specified conversions. */
3050 assign_parm_setup_stack (struct assign_parm_data_all *all, tree parm,
3051 struct assign_parm_data_one *data)
3053 /* Value must be stored in the stack slot STACK_PARM during function
3055 bool to_conversion = false;
3057 assign_parm_remove_parallels (data);
3059 if (data->promoted_mode != data->nominal_mode)
3061 /* Conversion is required. */
3062 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
3064 emit_move_insn (tempreg, validize_mem (data->entry_parm));
3066 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
3067 to_conversion = true;
3069 data->entry_parm = convert_to_mode (data->nominal_mode, tempreg,
3070 TYPE_UNSIGNED (TREE_TYPE (parm)));
3072 if (data->stack_parm)
3074 int offset = subreg_lowpart_offset (data->nominal_mode,
3075 GET_MODE (data->stack_parm));
3076 /* ??? This may need a big-endian conversion on sparc64. */
3078 = adjust_address (data->stack_parm, data->nominal_mode, 0);
3079 if (offset && MEM_OFFSET (data->stack_parm))
3080 set_mem_offset (data->stack_parm,
3081 plus_constant (MEM_OFFSET (data->stack_parm),
3086 if (data->entry_parm != data->stack_parm)
3090 if (data->stack_parm == 0)
3092 int align = STACK_SLOT_ALIGNMENT (data->passed_type,
3093 GET_MODE (data->entry_parm),
3094 TYPE_ALIGN (data->passed_type));
3096 = assign_stack_local (GET_MODE (data->entry_parm),
3097 GET_MODE_SIZE (GET_MODE (data->entry_parm)),
3099 set_mem_attributes (data->stack_parm, parm, 1);
3102 dest = validize_mem (data->stack_parm);
3103 src = validize_mem (data->entry_parm);
3107 /* Use a block move to handle potentially misaligned entry_parm. */
3109 push_to_sequence2 (all->first_conversion_insn,
3110 all->last_conversion_insn);
3111 to_conversion = true;
3113 emit_block_move (dest, src,
3114 GEN_INT (int_size_in_bytes (data->passed_type)),
3118 emit_move_insn (dest, src);
3123 all->first_conversion_insn = get_insns ();
3124 all->last_conversion_insn = get_last_insn ();
3128 SET_DECL_RTL (parm, data->stack_parm);
3131 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
3132 undo the frobbing that we did in assign_parms_augmented_arg_list. */
3135 assign_parms_unsplit_complex (struct assign_parm_data_all *all,
3136 VEC(tree, heap) *fnargs)
3139 tree orig_fnargs = all->orig_fnargs;
3142 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm), ++i)
3144 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE
3145 && targetm.calls.split_complex_arg (TREE_TYPE (parm)))
3147 rtx tmp, real, imag;
3148 enum machine_mode inner = GET_MODE_INNER (DECL_MODE (parm));
3150 real = DECL_RTL (VEC_index (tree, fnargs, i));
3151 imag = DECL_RTL (VEC_index (tree, fnargs, i + 1));
3152 if (inner != GET_MODE (real))
3154 real = gen_lowpart_SUBREG (inner, real);
3155 imag = gen_lowpart_SUBREG (inner, imag);
3158 if (TREE_ADDRESSABLE (parm))
3161 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (parm));
3162 int align = STACK_SLOT_ALIGNMENT (TREE_TYPE (parm),
3164 TYPE_ALIGN (TREE_TYPE (parm)));
3166 /* split_complex_arg put the real and imag parts in
3167 pseudos. Move them to memory. */
3168 tmp = assign_stack_local (DECL_MODE (parm), size, align);
3169 set_mem_attributes (tmp, parm, 1);
3170 rmem = adjust_address_nv (tmp, inner, 0);
3171 imem = adjust_address_nv (tmp, inner, GET_MODE_SIZE (inner));
3172 push_to_sequence2 (all->first_conversion_insn,
3173 all->last_conversion_insn);
3174 emit_move_insn (rmem, real);
3175 emit_move_insn (imem, imag);
3176 all->first_conversion_insn = get_insns ();
3177 all->last_conversion_insn = get_last_insn ();
3181 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3182 SET_DECL_RTL (parm, tmp);
3184 real = DECL_INCOMING_RTL (VEC_index (tree, fnargs, i));
3185 imag = DECL_INCOMING_RTL (VEC_index (tree, fnargs, i + 1));
3186 if (inner != GET_MODE (real))
3188 real = gen_lowpart_SUBREG (inner, real);
3189 imag = gen_lowpart_SUBREG (inner, imag);
3191 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3192 set_decl_incoming_rtl (parm, tmp, false);
3198 /* Assign RTL expressions to the function's parameters. This may involve
3199 copying them into registers and using those registers as the DECL_RTL. */
3202 assign_parms (tree fndecl)
3204 struct assign_parm_data_all all;
3206 VEC(tree, heap) *fnargs;
3209 crtl->args.internal_arg_pointer
3210 = targetm.calls.internal_arg_pointer ();
3212 assign_parms_initialize_all (&all);
3213 fnargs = assign_parms_augmented_arg_list (&all);
3215 for (i = 0; VEC_iterate (tree, fnargs, i, parm); ++i)
3217 struct assign_parm_data_one data;
3219 /* Extract the type of PARM; adjust it according to ABI. */
3220 assign_parm_find_data_types (&all, parm, &data);
3222 /* Early out for errors and void parameters. */
3223 if (data.passed_mode == VOIDmode)
3225 SET_DECL_RTL (parm, const0_rtx);
3226 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
3230 /* Estimate stack alignment from parameter alignment. */
3231 if (SUPPORTS_STACK_ALIGNMENT)
3233 unsigned int align = FUNCTION_ARG_BOUNDARY (data.promoted_mode,
3235 align = MINIMUM_ALIGNMENT (data.passed_type, data.promoted_mode,
3237 if (TYPE_ALIGN (data.nominal_type) > align)
3238 align = MINIMUM_ALIGNMENT (data.nominal_type,
3239 TYPE_MODE (data.nominal_type),
3240 TYPE_ALIGN (data.nominal_type));
3241 if (crtl->stack_alignment_estimated < align)
3243 gcc_assert (!crtl->stack_realign_processed);
3244 crtl->stack_alignment_estimated = align;
3248 if (cfun->stdarg && !DECL_CHAIN (parm))
3249 assign_parms_setup_varargs (&all, &data, false);
3251 /* Find out where the parameter arrives in this function. */
3252 assign_parm_find_entry_rtl (&all, &data);
3254 /* Find out where stack space for this parameter might be. */
3255 if (assign_parm_is_stack_parm (&all, &data))
3257 assign_parm_find_stack_rtl (parm, &data);
3258 assign_parm_adjust_entry_rtl (&data);
3261 /* Record permanently how this parm was passed. */
3262 set_decl_incoming_rtl (parm, data.entry_parm, data.passed_pointer);
3264 /* Update info on where next arg arrives in registers. */
3265 targetm.calls.function_arg_advance (&all.args_so_far, data.promoted_mode,
3266 data.passed_type, data.named_arg);
3268 assign_parm_adjust_stack_rtl (&data);
3270 if (assign_parm_setup_block_p (&data))
3271 assign_parm_setup_block (&all, parm, &data);
3272 else if (data.passed_pointer || use_register_for_decl (parm))
3273 assign_parm_setup_reg (&all, parm, &data);
3275 assign_parm_setup_stack (&all, parm, &data);
3278 if (targetm.calls.split_complex_arg)
3279 assign_parms_unsplit_complex (&all, fnargs);
3281 VEC_free (tree, heap, fnargs);
3283 /* Output all parameter conversion instructions (possibly including calls)
3284 now that all parameters have been copied out of hard registers. */
3285 emit_insn (all.first_conversion_insn);
3287 /* Estimate reload stack alignment from scalar return mode. */
3288 if (SUPPORTS_STACK_ALIGNMENT)
3290 if (DECL_RESULT (fndecl))
3292 tree type = TREE_TYPE (DECL_RESULT (fndecl));
3293 enum machine_mode mode = TYPE_MODE (type);
3297 && !AGGREGATE_TYPE_P (type))
3299 unsigned int align = GET_MODE_ALIGNMENT (mode);
3300 if (crtl->stack_alignment_estimated < align)
3302 gcc_assert (!crtl->stack_realign_processed);
3303 crtl->stack_alignment_estimated = align;
3309 /* If we are receiving a struct value address as the first argument, set up
3310 the RTL for the function result. As this might require code to convert
3311 the transmitted address to Pmode, we do this here to ensure that possible
3312 preliminary conversions of the address have been emitted already. */
3313 if (all.function_result_decl)
3315 tree result = DECL_RESULT (current_function_decl);
3316 rtx addr = DECL_RTL (all.function_result_decl);
3319 if (DECL_BY_REFERENCE (result))
3323 addr = convert_memory_address (Pmode, addr);
3324 x = gen_rtx_MEM (DECL_MODE (result), addr);
3325 set_mem_attributes (x, result, 1);
3327 SET_DECL_RTL (result, x);
3330 /* We have aligned all the args, so add space for the pretend args. */
3331 crtl->args.pretend_args_size = all.pretend_args_size;
3332 all.stack_args_size.constant += all.extra_pretend_bytes;
3333 crtl->args.size = all.stack_args_size.constant;
3335 /* Adjust function incoming argument size for alignment and
3338 #ifdef REG_PARM_STACK_SPACE
3339 crtl->args.size = MAX (crtl->args.size,
3340 REG_PARM_STACK_SPACE (fndecl));
3343 crtl->args.size = CEIL_ROUND (crtl->args.size,
3344 PARM_BOUNDARY / BITS_PER_UNIT);
3346 #ifdef ARGS_GROW_DOWNWARD
3347 crtl->args.arg_offset_rtx
3348 = (all.stack_args_size.var == 0 ? GEN_INT (-all.stack_args_size.constant)
3349 : expand_expr (size_diffop (all.stack_args_size.var,
3350 size_int (-all.stack_args_size.constant)),
3351 NULL_RTX, VOIDmode, EXPAND_NORMAL));
3353 crtl->args.arg_offset_rtx = ARGS_SIZE_RTX (all.stack_args_size);
3356 /* See how many bytes, if any, of its args a function should try to pop
3359 crtl->args.pops_args = targetm.calls.return_pops_args (fndecl,
3363 /* For stdarg.h function, save info about
3364 regs and stack space used by the named args. */
3366 crtl->args.info = all.args_so_far;
3368 /* Set the rtx used for the function return value. Put this in its
3369 own variable so any optimizers that need this information don't have
3370 to include tree.h. Do this here so it gets done when an inlined
3371 function gets output. */
3374 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
3375 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
3377 /* If scalar return value was computed in a pseudo-reg, or was a named
3378 return value that got dumped to the stack, copy that to the hard
3380 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
3382 tree decl_result = DECL_RESULT (fndecl);
3383 rtx decl_rtl = DECL_RTL (decl_result);
3385 if (REG_P (decl_rtl)
3386 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
3387 : DECL_REGISTER (decl_result))
3391 real_decl_rtl = targetm.calls.function_value (TREE_TYPE (decl_result),
3393 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
3394 /* The delay slot scheduler assumes that crtl->return_rtx
3395 holds the hard register containing the return value, not a
3396 temporary pseudo. */
3397 crtl->return_rtx = real_decl_rtl;
3402 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3403 For all seen types, gimplify their sizes. */
3406 gimplify_parm_type (tree *tp, int *walk_subtrees, void *data)
3413 if (POINTER_TYPE_P (t))
3415 else if (TYPE_SIZE (t) && !TREE_CONSTANT (TYPE_SIZE (t))
3416 && !TYPE_SIZES_GIMPLIFIED (t))
3418 gimplify_type_sizes (t, (gimple_seq *) data);
3426 /* Gimplify the parameter list for current_function_decl. This involves
3427 evaluating SAVE_EXPRs of variable sized parameters and generating code
3428 to implement callee-copies reference parameters. Returns a sequence of
3429 statements to add to the beginning of the function. */
3432 gimplify_parameters (void)
3434 struct assign_parm_data_all all;
3436 gimple_seq stmts = NULL;
3437 VEC(tree, heap) *fnargs;
3440 assign_parms_initialize_all (&all);
3441 fnargs = assign_parms_augmented_arg_list (&all);
3443 for (i = 0; VEC_iterate (tree, fnargs, i, parm); ++i)
3445 struct assign_parm_data_one data;
3447 /* Extract the type of PARM; adjust it according to ABI. */
3448 assign_parm_find_data_types (&all, parm, &data);
3450 /* Early out for errors and void parameters. */
3451 if (data.passed_mode == VOIDmode || DECL_SIZE (parm) == NULL)
3454 /* Update info on where next arg arrives in registers. */
3455 targetm.calls.function_arg_advance (&all.args_so_far, data.promoted_mode,
3456 data.passed_type, data.named_arg);
3458 /* ??? Once upon a time variable_size stuffed parameter list
3459 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3460 turned out to be less than manageable in the gimple world.
3461 Now we have to hunt them down ourselves. */
3462 walk_tree_without_duplicates (&data.passed_type,
3463 gimplify_parm_type, &stmts);
3465 if (TREE_CODE (DECL_SIZE_UNIT (parm)) != INTEGER_CST)
3467 gimplify_one_sizepos (&DECL_SIZE (parm), &stmts);
3468 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm), &stmts);
3471 if (data.passed_pointer)
3473 tree type = TREE_TYPE (data.passed_type);
3474 if (reference_callee_copied (&all.args_so_far, TYPE_MODE (type),
3475 type, data.named_arg))
3479 /* For constant-sized objects, this is trivial; for
3480 variable-sized objects, we have to play games. */
3481 if (TREE_CODE (DECL_SIZE_UNIT (parm)) == INTEGER_CST
3482 && !(flag_stack_check == GENERIC_STACK_CHECK
3483 && compare_tree_int (DECL_SIZE_UNIT (parm),
3484 STACK_CHECK_MAX_VAR_SIZE) > 0))
3486 local = create_tmp_var (type, get_name (parm));
3487 DECL_IGNORED_P (local) = 0;
3488 /* If PARM was addressable, move that flag over
3489 to the local copy, as its address will be taken,
3491 if (TREE_ADDRESSABLE (parm))
3493 TREE_ADDRESSABLE (parm) = 0;
3494 TREE_ADDRESSABLE (local) = 1;
3499 tree ptr_type, addr;
3501 ptr_type = build_pointer_type (type);
3502 addr = create_tmp_var (ptr_type, get_name (parm));
3503 DECL_IGNORED_P (addr) = 0;
3504 local = build_fold_indirect_ref (addr);
3506 t = built_in_decls[BUILT_IN_ALLOCA];
3507 t = build_call_expr (t, 1, DECL_SIZE_UNIT (parm));
3508 t = fold_convert (ptr_type, t);
3509 t = build2 (MODIFY_EXPR, TREE_TYPE (addr), addr, t);
3510 gimplify_and_add (t, &stmts);
3513 gimplify_assign (local, parm, &stmts);
3515 SET_DECL_VALUE_EXPR (parm, local);
3516 DECL_HAS_VALUE_EXPR_P (parm) = 1;
3521 VEC_free (tree, heap, fnargs);
3526 /* Compute the size and offset from the start of the stacked arguments for a
3527 parm passed in mode PASSED_MODE and with type TYPE.
3529 INITIAL_OFFSET_PTR points to the current offset into the stacked
3532 The starting offset and size for this parm are returned in
3533 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3534 nonzero, the offset is that of stack slot, which is returned in
3535 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3536 padding required from the initial offset ptr to the stack slot.
3538 IN_REGS is nonzero if the argument will be passed in registers. It will
3539 never be set if REG_PARM_STACK_SPACE is not defined.
3541 FNDECL is the function in which the argument was defined.
3543 There are two types of rounding that are done. The first, controlled by
3544 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
3545 list to be aligned to the specific boundary (in bits). This rounding
3546 affects the initial and starting offsets, but not the argument size.
3548 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3549 optionally rounds the size of the parm to PARM_BOUNDARY. The
3550 initial offset is not affected by this rounding, while the size always
3551 is and the starting offset may be. */
3553 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3554 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3555 callers pass in the total size of args so far as
3556 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
3559 locate_and_pad_parm (enum machine_mode passed_mode, tree type, int in_regs,
3560 int partial, tree fndecl ATTRIBUTE_UNUSED,
3561 struct args_size *initial_offset_ptr,
3562 struct locate_and_pad_arg_data *locate)
3565 enum direction where_pad;
3566 unsigned int boundary;
3567 int reg_parm_stack_space = 0;
3568 int part_size_in_regs;
3570 #ifdef REG_PARM_STACK_SPACE
3571 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
3573 /* If we have found a stack parm before we reach the end of the
3574 area reserved for registers, skip that area. */
3577 if (reg_parm_stack_space > 0)
3579 if (initial_offset_ptr->var)
3581 initial_offset_ptr->var
3582 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
3583 ssize_int (reg_parm_stack_space));
3584 initial_offset_ptr->constant = 0;
3586 else if (initial_offset_ptr->constant < reg_parm_stack_space)
3587 initial_offset_ptr->constant = reg_parm_stack_space;
3590 #endif /* REG_PARM_STACK_SPACE */
3592 part_size_in_regs = (reg_parm_stack_space == 0 ? partial : 0);
3595 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
3596 where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
3597 boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
3598 locate->where_pad = where_pad;
3600 /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT. */
3601 if (boundary > MAX_SUPPORTED_STACK_ALIGNMENT)
3602 boundary = MAX_SUPPORTED_STACK_ALIGNMENT;
3604 locate->boundary = boundary;
3606 if (SUPPORTS_STACK_ALIGNMENT)
3608 /* stack_alignment_estimated can't change after stack has been
3610 if (crtl->stack_alignment_estimated < boundary)
3612 if (!crtl->stack_realign_processed)
3613 crtl->stack_alignment_estimated = boundary;
3616 /* If stack is realigned and stack alignment value
3617 hasn't been finalized, it is OK not to increase
3618 stack_alignment_estimated. The bigger alignment
3619 requirement is recorded in stack_alignment_needed
3621 gcc_assert (!crtl->stack_realign_finalized
3622 && crtl->stack_realign_needed);
3627 /* Remember if the outgoing parameter requires extra alignment on the
3628 calling function side. */
3629 if (crtl->stack_alignment_needed < boundary)
3630 crtl->stack_alignment_needed = boundary;
3631 if (crtl->preferred_stack_boundary < boundary)
3632 crtl->preferred_stack_boundary = boundary;
3634 #ifdef ARGS_GROW_DOWNWARD
3635 locate->slot_offset.constant = -initial_offset_ptr->constant;
3636 if (initial_offset_ptr->var)
3637 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
3638 initial_offset_ptr->var);
3642 if (where_pad != none
3643 && (!host_integerp (sizetree, 1)
3644 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
3645 s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
3646 SUB_PARM_SIZE (locate->slot_offset, s2);
3649 locate->slot_offset.constant += part_size_in_regs;
3652 #ifdef REG_PARM_STACK_SPACE
3653 || REG_PARM_STACK_SPACE (fndecl) > 0
3656 pad_to_arg_alignment (&locate->slot_offset, boundary,
3657 &locate->alignment_pad);
3659 locate->size.constant = (-initial_offset_ptr->constant
3660 - locate->slot_offset.constant);
3661 if (initial_offset_ptr->var)
3662 locate->size.var = size_binop (MINUS_EXPR,
3663 size_binop (MINUS_EXPR,
3665 initial_offset_ptr->var),
3666 locate->slot_offset.var);
3668 /* Pad_below needs the pre-rounded size to know how much to pad
3670 locate->offset = locate->slot_offset;
3671 if (where_pad == downward)
3672 pad_below (&locate->offset, passed_mode, sizetree);
3674 #else /* !ARGS_GROW_DOWNWARD */
3676 #ifdef REG_PARM_STACK_SPACE
3677 || REG_PARM_STACK_SPACE (fndecl) > 0
3680 pad_to_arg_alignment (initial_offset_ptr, boundary,
3681 &locate->alignment_pad);
3682 locate->slot_offset = *initial_offset_ptr;
3684 #ifdef PUSH_ROUNDING
3685 if (passed_mode != BLKmode)
3686 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
3689 /* Pad_below needs the pre-rounded size to know how much to pad below
3690 so this must be done before rounding up. */
3691 locate->offset = locate->slot_offset;
3692 if (where_pad == downward)
3693 pad_below (&locate->offset, passed_mode, sizetree);
3695 if (where_pad != none
3696 && (!host_integerp (sizetree, 1)
3697 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
3698 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
3700 ADD_PARM_SIZE (locate->size, sizetree);
3702 locate->size.constant -= part_size_in_regs;
3703 #endif /* ARGS_GROW_DOWNWARD */
3705 #ifdef FUNCTION_ARG_OFFSET
3706 locate->offset.constant += FUNCTION_ARG_OFFSET (passed_mode, type);
3710 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
3711 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
3714 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
3715 struct args_size *alignment_pad)
3717 tree save_var = NULL_TREE;
3718 HOST_WIDE_INT save_constant = 0;
3719 int boundary_in_bytes = boundary / BITS_PER_UNIT;
3720 HOST_WIDE_INT sp_offset = STACK_POINTER_OFFSET;
3722 #ifdef SPARC_STACK_BOUNDARY_HACK
3723 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
3724 the real alignment of %sp. However, when it does this, the
3725 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
3726 if (SPARC_STACK_BOUNDARY_HACK)
3730 if (boundary > PARM_BOUNDARY)
3732 save_var = offset_ptr->var;
3733 save_constant = offset_ptr->constant;
3736 alignment_pad->var = NULL_TREE;
3737 alignment_pad->constant = 0;
3739 if (boundary > BITS_PER_UNIT)
3741 if (offset_ptr->var)
3743 tree sp_offset_tree = ssize_int (sp_offset);
3744 tree offset = size_binop (PLUS_EXPR,
3745 ARGS_SIZE_TREE (*offset_ptr),
3747 #ifdef ARGS_GROW_DOWNWARD
3748 tree rounded = round_down (offset, boundary / BITS_PER_UNIT);
3750 tree rounded = round_up (offset, boundary / BITS_PER_UNIT);
3753 offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
3754 /* ARGS_SIZE_TREE includes constant term. */
3755 offset_ptr->constant = 0;
3756 if (boundary > PARM_BOUNDARY)
3757 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
3762 offset_ptr->constant = -sp_offset +
3763 #ifdef ARGS_GROW_DOWNWARD
3764 FLOOR_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
3766 CEIL_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
3768 if (boundary > PARM_BOUNDARY)
3769 alignment_pad->constant = offset_ptr->constant - save_constant;
3775 pad_below (struct args_size *offset_ptr, enum machine_mode passed_mode, tree sizetree)
3777 if (passed_mode != BLKmode)
3779 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
3780 offset_ptr->constant
3781 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
3782 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
3783 - GET_MODE_SIZE (passed_mode));
3787 if (TREE_CODE (sizetree) != INTEGER_CST
3788 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
3790 /* Round the size up to multiple of PARM_BOUNDARY bits. */
3791 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
3793 ADD_PARM_SIZE (*offset_ptr, s2);
3794 SUB_PARM_SIZE (*offset_ptr, sizetree);
3800 /* True if register REGNO was alive at a place where `setjmp' was
3801 called and was set more than once or is an argument. Such regs may
3802 be clobbered by `longjmp'. */
3805 regno_clobbered_at_setjmp (bitmap setjmp_crosses, int regno)
3807 /* There appear to be cases where some local vars never reach the
3808 backend but have bogus regnos. */
3809 if (regno >= max_reg_num ())
3812 return ((REG_N_SETS (regno) > 1
3813 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR), regno))
3814 && REGNO_REG_SET_P (setjmp_crosses, regno));
3817 /* Walk the tree of blocks describing the binding levels within a
3818 function and warn about variables the might be killed by setjmp or
3819 vfork. This is done after calling flow_analysis before register
3820 allocation since that will clobber the pseudo-regs to hard
3824 setjmp_vars_warning (bitmap setjmp_crosses, tree block)
3828 for (decl = BLOCK_VARS (block); decl; decl = DECL_CHAIN (decl))
3830 if (TREE_CODE (decl) == VAR_DECL
3831 && DECL_RTL_SET_P (decl)
3832 && REG_P (DECL_RTL (decl))
3833 && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
3834 warning (OPT_Wclobbered, "variable %q+D might be clobbered by"
3835 " %<longjmp%> or %<vfork%>", decl);
3838 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = BLOCK_CHAIN (sub))
3839 setjmp_vars_warning (setjmp_crosses, sub);
3842 /* Do the appropriate part of setjmp_vars_warning
3843 but for arguments instead of local variables. */
3846 setjmp_args_warning (bitmap setjmp_crosses)
3849 for (decl = DECL_ARGUMENTS (current_function_decl);
3850 decl; decl = DECL_CHAIN (decl))
3851 if (DECL_RTL (decl) != 0
3852 && REG_P (DECL_RTL (decl))
3853 && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
3854 warning (OPT_Wclobbered,
3855 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
3859 /* Generate warning messages for variables live across setjmp. */
3862 generate_setjmp_warnings (void)
3864 bitmap setjmp_crosses = regstat_get_setjmp_crosses ();
3866 if (n_basic_blocks == NUM_FIXED_BLOCKS
3867 || bitmap_empty_p (setjmp_crosses))
3870 setjmp_vars_warning (setjmp_crosses, DECL_INITIAL (current_function_decl));
3871 setjmp_args_warning (setjmp_crosses);
3875 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
3876 and create duplicate blocks. */
3877 /* ??? Need an option to either create block fragments or to create
3878 abstract origin duplicates of a source block. It really depends
3879 on what optimization has been performed. */
3882 reorder_blocks (void)
3884 tree block = DECL_INITIAL (current_function_decl);
3885 VEC(tree,heap) *block_stack;
3887 if (block == NULL_TREE)
3890 block_stack = VEC_alloc (tree, heap, 10);
3892 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
3893 clear_block_marks (block);
3895 /* Prune the old trees away, so that they don't get in the way. */
3896 BLOCK_SUBBLOCKS (block) = NULL_TREE;
3897 BLOCK_CHAIN (block) = NULL_TREE;
3899 /* Recreate the block tree from the note nesting. */
3900 reorder_blocks_1 (get_insns (), block, &block_stack);
3901 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
3903 VEC_free (tree, heap, block_stack);
3906 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
3909 clear_block_marks (tree block)
3913 TREE_ASM_WRITTEN (block) = 0;
3914 clear_block_marks (BLOCK_SUBBLOCKS (block));
3915 block = BLOCK_CHAIN (block);
3920 reorder_blocks_1 (rtx insns, tree current_block, VEC(tree,heap) **p_block_stack)
3924 for (insn = insns; insn; insn = NEXT_INSN (insn))
3928 if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_BEG)
3930 tree block = NOTE_BLOCK (insn);
3933 origin = (BLOCK_FRAGMENT_ORIGIN (block)
3934 ? BLOCK_FRAGMENT_ORIGIN (block)
3937 /* If we have seen this block before, that means it now
3938 spans multiple address regions. Create a new fragment. */
3939 if (TREE_ASM_WRITTEN (block))
3941 tree new_block = copy_node (block);
3943 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
3944 BLOCK_FRAGMENT_CHAIN (new_block)
3945 = BLOCK_FRAGMENT_CHAIN (origin);
3946 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
3948 NOTE_BLOCK (insn) = new_block;
3952 BLOCK_SUBBLOCKS (block) = 0;
3953 TREE_ASM_WRITTEN (block) = 1;
3954 /* When there's only one block for the entire function,
3955 current_block == block and we mustn't do this, it
3956 will cause infinite recursion. */
3957 if (block != current_block)
3959 if (block != origin)
3960 gcc_assert (BLOCK_SUPERCONTEXT (origin) == current_block);
3962 BLOCK_SUPERCONTEXT (block) = current_block;
3963 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
3964 BLOCK_SUBBLOCKS (current_block) = block;
3965 current_block = origin;
3967 VEC_safe_push (tree, heap, *p_block_stack, block);
3969 else if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_END)
3971 NOTE_BLOCK (insn) = VEC_pop (tree, *p_block_stack);
3972 BLOCK_SUBBLOCKS (current_block)
3973 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
3974 current_block = BLOCK_SUPERCONTEXT (current_block);
3980 /* Reverse the order of elements in the chain T of blocks,
3981 and return the new head of the chain (old last element). */
3984 blocks_nreverse (tree t)
3986 tree prev = 0, decl, next;
3987 for (decl = t; decl; decl = next)
3989 next = BLOCK_CHAIN (decl);
3990 BLOCK_CHAIN (decl) = prev;
3996 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
3997 non-NULL, list them all into VECTOR, in a depth-first preorder
3998 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
4002 all_blocks (tree block, tree *vector)
4008 TREE_ASM_WRITTEN (block) = 0;
4010 /* Record this block. */
4012 vector[n_blocks] = block;
4016 /* Record the subblocks, and their subblocks... */
4017 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
4018 vector ? vector + n_blocks : 0);
4019 block = BLOCK_CHAIN (block);
4025 /* Return a vector containing all the blocks rooted at BLOCK. The
4026 number of elements in the vector is stored in N_BLOCKS_P. The
4027 vector is dynamically allocated; it is the caller's responsibility
4028 to call `free' on the pointer returned. */
4031 get_block_vector (tree block, int *n_blocks_p)
4035 *n_blocks_p = all_blocks (block, NULL);
4036 block_vector = XNEWVEC (tree, *n_blocks_p);
4037 all_blocks (block, block_vector);
4039 return block_vector;
4042 static GTY(()) int next_block_index = 2;
4044 /* Set BLOCK_NUMBER for all the blocks in FN. */
4047 number_blocks (tree fn)
4053 /* For SDB and XCOFF debugging output, we start numbering the blocks
4054 from 1 within each function, rather than keeping a running
4056 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
4057 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
4058 next_block_index = 1;
4061 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
4063 /* The top-level BLOCK isn't numbered at all. */
4064 for (i = 1; i < n_blocks; ++i)
4065 /* We number the blocks from two. */
4066 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
4068 free (block_vector);
4073 /* If VAR is present in a subblock of BLOCK, return the subblock. */
4076 debug_find_var_in_block_tree (tree var, tree block)
4080 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
4084 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
4086 tree ret = debug_find_var_in_block_tree (var, t);
4094 /* Keep track of whether we're in a dummy function context. If we are,
4095 we don't want to invoke the set_current_function hook, because we'll
4096 get into trouble if the hook calls target_reinit () recursively or
4097 when the initial initialization is not yet complete. */
4099 static bool in_dummy_function;
4101 /* Invoke the target hook when setting cfun. Update the optimization options
4102 if the function uses different options than the default. */
4105 invoke_set_current_function_hook (tree fndecl)
4107 if (!in_dummy_function)
4109 tree opts = ((fndecl)
4110 ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl)
4111 : optimization_default_node);
4114 opts = optimization_default_node;
4116 /* Change optimization options if needed. */
4117 if (optimization_current_node != opts)
4119 optimization_current_node = opts;
4120 cl_optimization_restore (TREE_OPTIMIZATION (opts));
4123 targetm.set_current_function (fndecl);
4127 /* cfun should never be set directly; use this function. */
4130 set_cfun (struct function *new_cfun)
4132 if (cfun != new_cfun)
4135 invoke_set_current_function_hook (new_cfun ? new_cfun->decl : NULL_TREE);
4139 /* Initialized with NOGC, making this poisonous to the garbage collector. */
4141 static VEC(function_p,heap) *cfun_stack;
4143 /* Push the current cfun onto the stack, and set cfun to new_cfun. */
4146 push_cfun (struct function *new_cfun)
4148 VEC_safe_push (function_p, heap, cfun_stack, cfun);
4149 set_cfun (new_cfun);
4152 /* Pop cfun from the stack. */
4157 struct function *new_cfun = VEC_pop (function_p, cfun_stack);
4158 set_cfun (new_cfun);
4161 /* Return value of funcdef and increase it. */
4163 get_next_funcdef_no (void)
4165 return funcdef_no++;
4168 /* Allocate a function structure for FNDECL and set its contents
4169 to the defaults. Set cfun to the newly-allocated object.
4170 Some of the helper functions invoked during initialization assume
4171 that cfun has already been set. Therefore, assign the new object
4172 directly into cfun and invoke the back end hook explicitly at the
4173 very end, rather than initializing a temporary and calling set_cfun
4176 ABSTRACT_P is true if this is a function that will never be seen by
4177 the middle-end. Such functions are front-end concepts (like C++
4178 function templates) that do not correspond directly to functions
4179 placed in object files. */
4182 allocate_struct_function (tree fndecl, bool abstract_p)
4185 tree fntype = fndecl ? TREE_TYPE (fndecl) : NULL_TREE;
4187 cfun = ggc_alloc_cleared_function ();
4189 init_eh_for_function ();
4191 if (init_machine_status)
4192 cfun->machine = (*init_machine_status) ();
4194 #ifdef OVERRIDE_ABI_FORMAT
4195 OVERRIDE_ABI_FORMAT (fndecl);
4198 invoke_set_current_function_hook (fndecl);
4200 if (fndecl != NULL_TREE)
4202 DECL_STRUCT_FUNCTION (fndecl) = cfun;
4203 cfun->decl = fndecl;
4204 current_function_funcdef_no = get_next_funcdef_no ();
4206 result = DECL_RESULT (fndecl);
4207 if (!abstract_p && aggregate_value_p (result, fndecl))
4209 #ifdef PCC_STATIC_STRUCT_RETURN
4210 cfun->returns_pcc_struct = 1;
4212 cfun->returns_struct = 1;
4217 && TYPE_ARG_TYPES (fntype) != 0
4218 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4219 != void_type_node));
4221 /* Assume all registers in stdarg functions need to be saved. */
4222 cfun->va_list_gpr_size = VA_LIST_MAX_GPR_SIZE;
4223 cfun->va_list_fpr_size = VA_LIST_MAX_FPR_SIZE;
4225 /* ??? This could be set on a per-function basis by the front-end
4226 but is this worth the hassle? */
4227 cfun->can_throw_non_call_exceptions = flag_non_call_exceptions;
4231 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
4232 instead of just setting it. */
4235 push_struct_function (tree fndecl)
4237 VEC_safe_push (function_p, heap, cfun_stack, cfun);
4238 allocate_struct_function (fndecl, false);
4241 /* Reset crtl and other non-struct-function variables to defaults as
4242 appropriate for emitting rtl at the start of a function. */
4245 prepare_function_start (void)
4247 gcc_assert (!crtl->emit.x_last_insn);
4250 init_varasm_status ();
4252 default_rtl_profile ();
4254 cse_not_expected = ! optimize;
4256 /* Caller save not needed yet. */
4257 caller_save_needed = 0;
4259 /* We haven't done register allocation yet. */
4262 /* Indicate that we have not instantiated virtual registers yet. */
4263 virtuals_instantiated = 0;
4265 /* Indicate that we want CONCATs now. */
4266 generating_concat_p = 1;
4268 /* Indicate we have no need of a frame pointer yet. */
4269 frame_pointer_needed = 0;
4272 /* Initialize the rtl expansion mechanism so that we can do simple things
4273 like generate sequences. This is used to provide a context during global
4274 initialization of some passes. You must call expand_dummy_function_end
4275 to exit this context. */
4278 init_dummy_function_start (void)
4280 gcc_assert (!in_dummy_function);
4281 in_dummy_function = true;
4282 push_struct_function (NULL_TREE);
4283 prepare_function_start ();
4286 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
4287 and initialize static variables for generating RTL for the statements
4291 init_function_start (tree subr)
4293 if (subr && DECL_STRUCT_FUNCTION (subr))
4294 set_cfun (DECL_STRUCT_FUNCTION (subr));
4296 allocate_struct_function (subr, false);
4297 prepare_function_start ();
4299 /* Warn if this value is an aggregate type,
4300 regardless of which calling convention we are using for it. */
4301 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
4302 warning (OPT_Waggregate_return, "function returns an aggregate");
4305 /* Make sure all values used by the optimization passes have sane defaults. */
4307 init_function_for_compilation (void)
4313 struct rtl_opt_pass pass_init_function =
4317 "*init_function", /* name */
4319 init_function_for_compilation, /* execute */
4322 0, /* static_pass_number */
4323 TV_NONE, /* tv_id */
4324 0, /* properties_required */
4325 0, /* properties_provided */
4326 0, /* properties_destroyed */
4327 0, /* todo_flags_start */
4328 0 /* todo_flags_finish */
4334 expand_main_function (void)
4336 #if (defined(INVOKE__main) \
4337 || (!defined(HAS_INIT_SECTION) \
4338 && !defined(INIT_SECTION_ASM_OP) \
4339 && !defined(INIT_ARRAY_SECTION_ASM_OP)))
4340 emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0);
4344 /* Expand code to initialize the stack_protect_guard. This is invoked at
4345 the beginning of a function to be protected. */
4347 #ifndef HAVE_stack_protect_set
4348 # define HAVE_stack_protect_set 0
4349 # define gen_stack_protect_set(x,y) (gcc_unreachable (), NULL_RTX)
4353 stack_protect_prologue (void)
4355 tree guard_decl = targetm.stack_protect_guard ();
4358 x = expand_normal (crtl->stack_protect_guard);
4359 y = expand_normal (guard_decl);
4361 /* Allow the target to copy from Y to X without leaking Y into a
4363 if (HAVE_stack_protect_set)
4365 rtx insn = gen_stack_protect_set (x, y);
4373 /* Otherwise do a straight move. */
4374 emit_move_insn (x, y);
4377 /* Expand code to verify the stack_protect_guard. This is invoked at
4378 the end of a function to be protected. */
4380 #ifndef HAVE_stack_protect_test
4381 # define HAVE_stack_protect_test 0
4382 # define gen_stack_protect_test(x, y, z) (gcc_unreachable (), NULL_RTX)
4386 stack_protect_epilogue (void)
4388 tree guard_decl = targetm.stack_protect_guard ();
4389 rtx label = gen_label_rtx ();
4392 x = expand_normal (crtl->stack_protect_guard);
4393 y = expand_normal (guard_decl);
4395 /* Allow the target to compare Y with X without leaking either into
4397 switch (HAVE_stack_protect_test != 0)
4400 tmp = gen_stack_protect_test (x, y, label);
4409 emit_cmp_and_jump_insns (x, y, EQ, NULL_RTX, ptr_mode, 1, label);
4413 /* The noreturn predictor has been moved to the tree level. The rtl-level
4414 predictors estimate this branch about 20%, which isn't enough to get
4415 things moved out of line. Since this is the only extant case of adding
4416 a noreturn function at the rtl level, it doesn't seem worth doing ought
4417 except adding the prediction by hand. */
4418 tmp = get_last_insn ();
4420 predict_insn_def (tmp, PRED_NORETURN, TAKEN);
4422 expand_expr_stmt (targetm.stack_protect_fail ());
4426 /* Start the RTL for a new function, and set variables used for
4428 SUBR is the FUNCTION_DECL node.
4429 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4430 the function's parameters, which must be run at any return statement. */
4433 expand_function_start (tree subr)
4435 /* Make sure volatile mem refs aren't considered
4436 valid operands of arithmetic insns. */
4437 init_recog_no_volatile ();
4441 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
4444 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
4446 /* Make the label for return statements to jump to. Do not special
4447 case machines with special return instructions -- they will be
4448 handled later during jump, ifcvt, or epilogue creation. */
4449 return_label = gen_label_rtx ();
4451 /* Initialize rtx used to return the value. */
4452 /* Do this before assign_parms so that we copy the struct value address
4453 before any library calls that assign parms might generate. */
4455 /* Decide whether to return the value in memory or in a register. */
4456 if (aggregate_value_p (DECL_RESULT (subr), subr))
4458 /* Returning something that won't go in a register. */
4459 rtx value_address = 0;
4461 #ifdef PCC_STATIC_STRUCT_RETURN
4462 if (cfun->returns_pcc_struct)
4464 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
4465 value_address = assemble_static_space (size);
4470 rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 2);
4471 /* Expect to be passed the address of a place to store the value.
4472 If it is passed as an argument, assign_parms will take care of
4476 value_address = gen_reg_rtx (Pmode);
4477 emit_move_insn (value_address, sv);
4482 rtx x = value_address;
4483 if (!DECL_BY_REFERENCE (DECL_RESULT (subr)))
4485 x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), x);
4486 set_mem_attributes (x, DECL_RESULT (subr), 1);
4488 SET_DECL_RTL (DECL_RESULT (subr), x);
4491 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
4492 /* If return mode is void, this decl rtl should not be used. */
4493 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
4496 /* Compute the return values into a pseudo reg, which we will copy
4497 into the true return register after the cleanups are done. */
4498 tree return_type = TREE_TYPE (DECL_RESULT (subr));
4499 if (TYPE_MODE (return_type) != BLKmode
4500 && targetm.calls.return_in_msb (return_type))
4501 /* expand_function_end will insert the appropriate padding in
4502 this case. Use the return value's natural (unpadded) mode
4503 within the function proper. */
4504 SET_DECL_RTL (DECL_RESULT (subr),
4505 gen_reg_rtx (TYPE_MODE (return_type)));
4508 /* In order to figure out what mode to use for the pseudo, we
4509 figure out what the mode of the eventual return register will
4510 actually be, and use that. */
4511 rtx hard_reg = hard_function_value (return_type, subr, 0, 1);
4513 /* Structures that are returned in registers are not
4514 aggregate_value_p, so we may see a PARALLEL or a REG. */
4515 if (REG_P (hard_reg))
4516 SET_DECL_RTL (DECL_RESULT (subr),
4517 gen_reg_rtx (GET_MODE (hard_reg)));
4520 gcc_assert (GET_CODE (hard_reg) == PARALLEL);
4521 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
4525 /* Set DECL_REGISTER flag so that expand_function_end will copy the
4526 result to the real return register(s). */
4527 DECL_REGISTER (DECL_RESULT (subr)) = 1;
4530 /* Initialize rtx for parameters and local variables.
4531 In some cases this requires emitting insns. */
4532 assign_parms (subr);
4534 /* If function gets a static chain arg, store it. */
4535 if (cfun->static_chain_decl)
4537 tree parm = cfun->static_chain_decl;
4538 rtx local, chain, insn;
4540 local = gen_reg_rtx (Pmode);
4541 chain = targetm.calls.static_chain (current_function_decl, true);
4543 set_decl_incoming_rtl (parm, chain, false);
4544 SET_DECL_RTL (parm, local);
4545 mark_reg_pointer (local, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
4547 insn = emit_move_insn (local, chain);
4549 /* Mark the register as eliminable, similar to parameters. */
4551 && reg_mentioned_p (arg_pointer_rtx, XEXP (chain, 0)))
4552 set_unique_reg_note (insn, REG_EQUIV, chain);
4555 /* If the function receives a non-local goto, then store the
4556 bits we need to restore the frame pointer. */
4557 if (cfun->nonlocal_goto_save_area)
4562 /* ??? We need to do this save early. Unfortunately here is
4563 before the frame variable gets declared. Help out... */
4564 tree var = TREE_OPERAND (cfun->nonlocal_goto_save_area, 0);
4565 if (!DECL_RTL_SET_P (var))
4568 t_save = build4 (ARRAY_REF, ptr_type_node,
4569 cfun->nonlocal_goto_save_area,
4570 integer_zero_node, NULL_TREE, NULL_TREE);
4571 r_save = expand_expr (t_save, NULL_RTX, VOIDmode, EXPAND_WRITE);
4572 r_save = convert_memory_address (Pmode, r_save);
4574 emit_move_insn (r_save, targetm.builtin_setjmp_frame_value ());
4575 update_nonlocal_goto_save_area ();
4578 /* The following was moved from init_function_start.
4579 The move is supposed to make sdb output more accurate. */
4580 /* Indicate the beginning of the function body,
4581 as opposed to parm setup. */
4582 emit_note (NOTE_INSN_FUNCTION_BEG);
4584 gcc_assert (NOTE_P (get_last_insn ()));
4586 parm_birth_insn = get_last_insn ();
4591 PROFILE_HOOK (current_function_funcdef_no);
4595 /* After the display initializations is where the stack checking
4597 if(flag_stack_check)
4598 stack_check_probe_note = emit_note (NOTE_INSN_DELETED);
4600 /* Make sure there is a line number after the function entry setup code. */
4601 force_next_line_note ();
4604 /* Undo the effects of init_dummy_function_start. */
4606 expand_dummy_function_end (void)
4608 gcc_assert (in_dummy_function);
4610 /* End any sequences that failed to be closed due to syntax errors. */
4611 while (in_sequence_p ())
4614 /* Outside function body, can't compute type's actual size
4615 until next function's body starts. */
4617 free_after_parsing (cfun);
4618 free_after_compilation (cfun);
4620 in_dummy_function = false;
4623 /* Call DOIT for each hard register used as a return value from
4624 the current function. */
4627 diddle_return_value (void (*doit) (rtx, void *), void *arg)
4629 rtx outgoing = crtl->return_rtx;
4634 if (REG_P (outgoing))
4635 (*doit) (outgoing, arg);
4636 else if (GET_CODE (outgoing) == PARALLEL)
4640 for (i = 0; i < XVECLEN (outgoing, 0); i++)
4642 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
4644 if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER)
4651 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
4657 clobber_return_register (void)
4659 diddle_return_value (do_clobber_return_reg, NULL);
4661 /* In case we do use pseudo to return value, clobber it too. */
4662 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
4664 tree decl_result = DECL_RESULT (current_function_decl);
4665 rtx decl_rtl = DECL_RTL (decl_result);
4666 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
4668 do_clobber_return_reg (decl_rtl, NULL);
4674 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
4680 use_return_register (void)
4682 diddle_return_value (do_use_return_reg, NULL);
4685 /* Possibly warn about unused parameters. */
4687 do_warn_unused_parameter (tree fn)
4691 for (decl = DECL_ARGUMENTS (fn);
4692 decl; decl = DECL_CHAIN (decl))
4693 if (!TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
4694 && DECL_NAME (decl) && !DECL_ARTIFICIAL (decl)
4695 && !TREE_NO_WARNING (decl))
4696 warning (OPT_Wunused_parameter, "unused parameter %q+D", decl);
4699 static GTY(()) rtx initial_trampoline;
4701 /* Generate RTL for the end of the current function. */
4704 expand_function_end (void)
4708 /* If arg_pointer_save_area was referenced only from a nested
4709 function, we will not have initialized it yet. Do that now. */
4710 if (arg_pointer_save_area && ! crtl->arg_pointer_save_area_init)
4711 get_arg_pointer_save_area ();
4713 /* If we are doing generic stack checking and this function makes calls,
4714 do a stack probe at the start of the function to ensure we have enough
4715 space for another stack frame. */
4716 if (flag_stack_check == GENERIC_STACK_CHECK)
4720 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4723 rtx max_frame_size = GEN_INT (STACK_CHECK_MAX_FRAME_SIZE);
4725 if (STACK_CHECK_MOVING_SP)
4726 anti_adjust_stack_and_probe (max_frame_size, true);
4728 probe_stack_range (STACK_OLD_CHECK_PROTECT, max_frame_size);
4731 emit_insn_before (seq, stack_check_probe_note);
4736 /* End any sequences that failed to be closed due to syntax errors. */
4737 while (in_sequence_p ())
4740 clear_pending_stack_adjust ();
4741 do_pending_stack_adjust ();
4743 /* Output a linenumber for the end of the function.
4744 SDB depends on this. */
4745 force_next_line_note ();
4746 set_curr_insn_source_location (input_location);
4748 /* Before the return label (if any), clobber the return
4749 registers so that they are not propagated live to the rest of
4750 the function. This can only happen with functions that drop
4751 through; if there had been a return statement, there would
4752 have either been a return rtx, or a jump to the return label.
4754 We delay actual code generation after the current_function_value_rtx
4756 clobber_after = get_last_insn ();
4758 /* Output the label for the actual return from the function. */
4759 emit_label (return_label);
4761 if (USING_SJLJ_EXCEPTIONS)
4763 /* Let except.c know where it should emit the call to unregister
4764 the function context for sjlj exceptions. */
4765 if (flag_exceptions)
4766 sjlj_emit_function_exit_after (get_last_insn ());
4770 /* We want to ensure that instructions that may trap are not
4771 moved into the epilogue by scheduling, because we don't
4772 always emit unwind information for the epilogue. */
4773 if (cfun->can_throw_non_call_exceptions)
4774 emit_insn (gen_blockage ());
4777 /* If this is an implementation of throw, do what's necessary to
4778 communicate between __builtin_eh_return and the epilogue. */
4779 expand_eh_return ();
4781 /* If scalar return value was computed in a pseudo-reg, or was a named
4782 return value that got dumped to the stack, copy that to the hard
4784 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
4786 tree decl_result = DECL_RESULT (current_function_decl);
4787 rtx decl_rtl = DECL_RTL (decl_result);
4789 if (REG_P (decl_rtl)
4790 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
4791 : DECL_REGISTER (decl_result))
4793 rtx real_decl_rtl = crtl->return_rtx;
4795 /* This should be set in assign_parms. */
4796 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl));
4798 /* If this is a BLKmode structure being returned in registers,
4799 then use the mode computed in expand_return. Note that if
4800 decl_rtl is memory, then its mode may have been changed,
4801 but that crtl->return_rtx has not. */
4802 if (GET_MODE (real_decl_rtl) == BLKmode)
4803 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
4805 /* If a non-BLKmode return value should be padded at the least
4806 significant end of the register, shift it left by the appropriate
4807 amount. BLKmode results are handled using the group load/store
4809 if (TYPE_MODE (TREE_TYPE (decl_result)) != BLKmode
4810 && targetm.calls.return_in_msb (TREE_TYPE (decl_result)))
4812 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl),
4813 REGNO (real_decl_rtl)),
4815 shift_return_value (GET_MODE (decl_rtl), true, real_decl_rtl);
4817 /* If a named return value dumped decl_return to memory, then
4818 we may need to re-do the PROMOTE_MODE signed/unsigned
4820 else if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
4822 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (decl_result));
4823 promote_function_mode (TREE_TYPE (decl_result),
4824 GET_MODE (decl_rtl), &unsignedp,
4825 TREE_TYPE (current_function_decl), 1);
4827 convert_move (real_decl_rtl, decl_rtl, unsignedp);
4829 else if (GET_CODE (real_decl_rtl) == PARALLEL)
4831 /* If expand_function_start has created a PARALLEL for decl_rtl,
4832 move the result to the real return registers. Otherwise, do
4833 a group load from decl_rtl for a named return. */
4834 if (GET_CODE (decl_rtl) == PARALLEL)
4835 emit_group_move (real_decl_rtl, decl_rtl);
4837 emit_group_load (real_decl_rtl, decl_rtl,
4838 TREE_TYPE (decl_result),
4839 int_size_in_bytes (TREE_TYPE (decl_result)));
4841 /* In the case of complex integer modes smaller than a word, we'll
4842 need to generate some non-trivial bitfield insertions. Do that
4843 on a pseudo and not the hard register. */
4844 else if (GET_CODE (decl_rtl) == CONCAT
4845 && GET_MODE_CLASS (GET_MODE (decl_rtl)) == MODE_COMPLEX_INT
4846 && GET_MODE_BITSIZE (GET_MODE (decl_rtl)) <= BITS_PER_WORD)
4848 int old_generating_concat_p;
4851 old_generating_concat_p = generating_concat_p;
4852 generating_concat_p = 0;
4853 tmp = gen_reg_rtx (GET_MODE (decl_rtl));
4854 generating_concat_p = old_generating_concat_p;
4856 emit_move_insn (tmp, decl_rtl);
4857 emit_move_insn (real_decl_rtl, tmp);
4860 emit_move_insn (real_decl_rtl, decl_rtl);
4864 /* If returning a structure, arrange to return the address of the value
4865 in a place where debuggers expect to find it.
4867 If returning a structure PCC style,
4868 the caller also depends on this value.
4869 And cfun->returns_pcc_struct is not necessarily set. */
4870 if (cfun->returns_struct
4871 || cfun->returns_pcc_struct)
4873 rtx value_address = DECL_RTL (DECL_RESULT (current_function_decl));
4874 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
4877 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))
4878 type = TREE_TYPE (type);
4880 value_address = XEXP (value_address, 0);
4882 outgoing = targetm.calls.function_value (build_pointer_type (type),
4883 current_function_decl, true);
4885 /* Mark this as a function return value so integrate will delete the
4886 assignment and USE below when inlining this function. */
4887 REG_FUNCTION_VALUE_P (outgoing) = 1;
4889 /* The address may be ptr_mode and OUTGOING may be Pmode. */
4890 value_address = convert_memory_address (GET_MODE (outgoing),
4893 emit_move_insn (outgoing, value_address);
4895 /* Show return register used to hold result (in this case the address
4897 crtl->return_rtx = outgoing;
4900 /* Emit the actual code to clobber return register. */
4905 clobber_return_register ();
4909 emit_insn_after (seq, clobber_after);
4912 /* Output the label for the naked return from the function. */
4913 if (naked_return_label)
4914 emit_label (naked_return_label);
4916 /* @@@ This is a kludge. We want to ensure that instructions that
4917 may trap are not moved into the epilogue by scheduling, because
4918 we don't always emit unwind information for the epilogue. */
4919 if (!USING_SJLJ_EXCEPTIONS && cfun->can_throw_non_call_exceptions)
4920 emit_insn (gen_blockage ());
4922 /* If stack protection is enabled for this function, check the guard. */
4923 if (crtl->stack_protect_guard)
4924 stack_protect_epilogue ();
4926 /* If we had calls to alloca, and this machine needs
4927 an accurate stack pointer to exit the function,
4928 insert some code to save and restore the stack pointer. */
4929 if (! EXIT_IGNORE_STACK
4930 && cfun->calls_alloca)
4934 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
4935 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
4938 /* ??? This should no longer be necessary since stupid is no longer with
4939 us, but there are some parts of the compiler (eg reload_combine, and
4940 sh mach_dep_reorg) that still try and compute their own lifetime info
4941 instead of using the general framework. */
4942 use_return_register ();
4946 get_arg_pointer_save_area (void)
4948 rtx ret = arg_pointer_save_area;
4952 ret = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
4953 arg_pointer_save_area = ret;
4956 if (! crtl->arg_pointer_save_area_init)
4960 /* Save the arg pointer at the beginning of the function. The
4961 generated stack slot may not be a valid memory address, so we
4962 have to check it and fix it if necessary. */
4964 emit_move_insn (validize_mem (ret),
4965 crtl->args.internal_arg_pointer);
4969 push_topmost_sequence ();
4970 emit_insn_after (seq, entry_of_function ());
4971 pop_topmost_sequence ();
4977 /* Add a list of INSNS to the hash HASHP, possibly allocating HASHP
4978 for the first time. */
4981 record_insns (rtx insns, rtx end, htab_t *hashp)
4984 htab_t hash = *hashp;
4988 = htab_create_ggc (17, htab_hash_pointer, htab_eq_pointer, NULL);
4990 for (tmp = insns; tmp != end; tmp = NEXT_INSN (tmp))
4992 void **slot = htab_find_slot (hash, tmp, INSERT);
4993 gcc_assert (*slot == NULL);
4998 /* INSN has been duplicated as COPY, as part of duping a basic block.
4999 If INSN is an epilogue insn, then record COPY as epilogue as well. */
5002 maybe_copy_epilogue_insn (rtx insn, rtx copy)
5006 if (epilogue_insn_hash == NULL
5007 || htab_find (epilogue_insn_hash, insn) == NULL)
5010 slot = htab_find_slot (epilogue_insn_hash, copy, INSERT);
5011 gcc_assert (*slot == NULL);
5015 /* Set the locator of the insn chain starting at INSN to LOC. */
5017 set_insn_locators (rtx insn, int loc)
5019 while (insn != NULL_RTX)
5022 INSN_LOCATOR (insn) = loc;
5023 insn = NEXT_INSN (insn);
5027 /* Determine if any INSNs in HASH are, or are part of, INSN. Because
5028 we can be running after reorg, SEQUENCE rtl is possible. */
5031 contains (const_rtx insn, htab_t hash)
5036 if (NONJUMP_INSN_P (insn) && GET_CODE (PATTERN (insn)) == SEQUENCE)
5039 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
5040 if (htab_find (hash, XVECEXP (PATTERN (insn), 0, i)))
5045 return htab_find (hash, insn) != NULL;
5049 prologue_epilogue_contains (const_rtx insn)
5051 if (contains (insn, prologue_insn_hash))
5053 if (contains (insn, epilogue_insn_hash))
5059 /* Insert gen_return at the end of block BB. This also means updating
5060 block_for_insn appropriately. */
5063 emit_return_into_block (basic_block bb)
5065 emit_jump_insn_after (gen_return (), BB_END (bb));
5067 #endif /* HAVE_return */
5069 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
5070 this into place with notes indicating where the prologue ends and where
5071 the epilogue begins. Update the basic block information when possible. */
5074 thread_prologue_and_epilogue_insns (void)
5078 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
5081 #if defined (HAVE_epilogue) || defined(HAVE_return)
5082 rtx epilogue_end = NULL_RTX;
5086 rtl_profile_for_bb (ENTRY_BLOCK_PTR);
5087 #ifdef HAVE_prologue
5091 seq = gen_prologue ();
5094 /* Insert an explicit USE for the frame pointer
5095 if the profiling is on and the frame pointer is required. */
5096 if (crtl->profile && frame_pointer_needed)
5097 emit_use (hard_frame_pointer_rtx);
5099 /* Retain a map of the prologue insns. */
5100 record_insns (seq, NULL, &prologue_insn_hash);
5101 emit_note (NOTE_INSN_PROLOGUE_END);
5103 #ifndef PROFILE_BEFORE_PROLOGUE
5104 /* Ensure that instructions are not moved into the prologue when
5105 profiling is on. The call to the profiling routine can be
5106 emitted within the live range of a call-clobbered register. */
5108 emit_insn (gen_blockage ());
5113 set_insn_locators (seq, prologue_locator);
5115 /* Can't deal with multiple successors of the entry block
5116 at the moment. Function should always have at least one
5118 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR));
5120 insert_insn_on_edge (seq, single_succ_edge (ENTRY_BLOCK_PTR));
5125 /* If the exit block has no non-fake predecessors, we don't need
5127 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5128 if ((e->flags & EDGE_FAKE) == 0)
5133 rtl_profile_for_bb (EXIT_BLOCK_PTR);
5135 if (optimize && HAVE_return)
5137 /* If we're allowed to generate a simple return instruction,
5138 then by definition we don't need a full epilogue. Examine
5139 the block that falls through to EXIT. If it does not
5140 contain any code, examine its predecessors and try to
5141 emit (conditional) return instructions. */
5146 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5147 if (e->flags & EDGE_FALLTHRU)
5153 /* Verify that there are no active instructions in the last block. */
5154 label = BB_END (last);
5155 while (label && !LABEL_P (label))
5157 if (active_insn_p (label))
5159 label = PREV_INSN (label);
5162 if (BB_HEAD (last) == label && LABEL_P (label))
5166 for (ei2 = ei_start (last->preds); (e = ei_safe_edge (ei2)); )
5168 basic_block bb = e->src;
5171 if (bb == ENTRY_BLOCK_PTR)
5178 if (!JUMP_P (jump) || JUMP_LABEL (jump) != label)
5184 /* If we have an unconditional jump, we can replace that
5185 with a simple return instruction. */
5186 if (simplejump_p (jump))
5188 emit_return_into_block (bb);
5192 /* If we have a conditional jump, we can try to replace
5193 that with a conditional return instruction. */
5194 else if (condjump_p (jump))
5196 if (! redirect_jump (jump, 0, 0))
5202 /* If this block has only one successor, it both jumps
5203 and falls through to the fallthru block, so we can't
5205 if (single_succ_p (bb))
5217 /* Fix up the CFG for the successful change we just made. */
5218 redirect_edge_succ (e, EXIT_BLOCK_PTR);
5221 /* Emit a return insn for the exit fallthru block. Whether
5222 this is still reachable will be determined later. */
5224 emit_barrier_after (BB_END (last));
5225 emit_return_into_block (last);
5226 epilogue_end = BB_END (last);
5227 single_succ_edge (last)->flags &= ~EDGE_FALLTHRU;
5233 /* A small fib -- epilogue is not yet completed, but we wish to re-use
5234 this marker for the splits of EH_RETURN patterns, and nothing else
5235 uses the flag in the meantime. */
5236 epilogue_completed = 1;
5238 #ifdef HAVE_eh_return
5239 /* Find non-fallthru edges that end with EH_RETURN instructions. On
5240 some targets, these get split to a special version of the epilogue
5241 code. In order to be able to properly annotate these with unwind
5242 info, try to split them now. If we get a valid split, drop an
5243 EPILOGUE_BEG note and mark the insns as epilogue insns. */
5244 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5246 rtx prev, last, trial;
5248 if (e->flags & EDGE_FALLTHRU)
5250 last = BB_END (e->src);
5251 if (!eh_returnjump_p (last))
5254 prev = PREV_INSN (last);
5255 trial = try_split (PATTERN (last), last, 1);
5259 record_insns (NEXT_INSN (prev), NEXT_INSN (trial), &epilogue_insn_hash);
5260 emit_note_after (NOTE_INSN_EPILOGUE_BEG, prev);
5264 /* Find the edge that falls through to EXIT. Other edges may exist
5265 due to RETURN instructions, but those don't need epilogues.
5266 There really shouldn't be a mixture -- either all should have
5267 been converted or none, however... */
5269 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5270 if (e->flags & EDGE_FALLTHRU)
5275 #ifdef HAVE_epilogue
5279 epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG);
5280 seq = gen_epilogue ();
5281 emit_jump_insn (seq);
5283 /* Retain a map of the epilogue insns. */
5284 record_insns (seq, NULL, &epilogue_insn_hash);
5285 set_insn_locators (seq, epilogue_locator);
5290 insert_insn_on_edge (seq, e);
5298 if (! next_active_insn (BB_END (e->src)))
5300 /* We have a fall-through edge to the exit block, the source is not
5301 at the end of the function, and there will be an assembler epilogue
5302 at the end of the function.
5303 We can't use force_nonfallthru here, because that would try to
5304 use return. Inserting a jump 'by hand' is extremely messy, so
5305 we take advantage of cfg_layout_finalize using
5306 fixup_fallthru_exit_predecessor. */
5307 cfg_layout_initialize (0);
5308 FOR_EACH_BB (cur_bb)
5309 if (cur_bb->index >= NUM_FIXED_BLOCKS
5310 && cur_bb->next_bb->index >= NUM_FIXED_BLOCKS)
5311 cur_bb->aux = cur_bb->next_bb;
5312 cfg_layout_finalize ();
5315 default_rtl_profile ();
5319 commit_edge_insertions ();
5321 /* The epilogue insns we inserted may cause the exit edge to no longer
5323 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5325 if (((e->flags & EDGE_FALLTHRU) != 0)
5326 && returnjump_p (BB_END (e->src)))
5327 e->flags &= ~EDGE_FALLTHRU;
5331 #ifdef HAVE_sibcall_epilogue
5332 /* Emit sibling epilogues before any sibling call sites. */
5333 for (ei = ei_start (EXIT_BLOCK_PTR->preds); (e = ei_safe_edge (ei)); )
5335 basic_block bb = e->src;
5336 rtx insn = BB_END (bb);
5339 || ! SIBLING_CALL_P (insn))
5346 emit_note (NOTE_INSN_EPILOGUE_BEG);
5347 emit_insn (gen_sibcall_epilogue ());
5351 /* Retain a map of the epilogue insns. Used in life analysis to
5352 avoid getting rid of sibcall epilogue insns. Do this before we
5353 actually emit the sequence. */
5354 record_insns (seq, NULL, &epilogue_insn_hash);
5355 set_insn_locators (seq, epilogue_locator);
5357 emit_insn_before (seq, insn);
5362 #ifdef HAVE_epilogue
5367 /* Similarly, move any line notes that appear after the epilogue.
5368 There is no need, however, to be quite so anal about the existence
5369 of such a note. Also possibly move
5370 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
5372 for (insn = epilogue_end; insn; insn = next)
5374 next = NEXT_INSN (insn);
5376 && (NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG))
5377 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
5382 /* Threading the prologue and epilogue changes the artificial refs
5383 in the entry and exit blocks. */
5384 epilogue_completed = 1;
5385 df_update_entry_exit_and_calls ();
5388 /* Reposition the prologue-end and epilogue-begin notes after
5389 instruction scheduling. */
5392 reposition_prologue_and_epilogue_notes (void)
5394 #if defined (HAVE_prologue) || defined (HAVE_epilogue) \
5395 || defined (HAVE_sibcall_epilogue)
5396 /* Since the hash table is created on demand, the fact that it is
5397 non-null is a signal that it is non-empty. */
5398 if (prologue_insn_hash != NULL)
5400 size_t len = htab_elements (prologue_insn_hash);
5401 rtx insn, last = NULL, note = NULL;
5403 /* Scan from the beginning until we reach the last prologue insn. */
5404 /* ??? While we do have the CFG intact, there are two problems:
5405 (1) The prologue can contain loops (typically probing the stack),
5406 which means that the end of the prologue isn't in the first bb.
5407 (2) Sometimes the PROLOGUE_END note gets pushed into the next bb. */
5408 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
5412 if (NOTE_KIND (insn) == NOTE_INSN_PROLOGUE_END)
5415 else if (contains (insn, prologue_insn_hash))
5427 /* Scan forward looking for the PROLOGUE_END note. It should
5428 be right at the beginning of the block, possibly with other
5429 insn notes that got moved there. */
5430 for (note = NEXT_INSN (last); ; note = NEXT_INSN (note))
5433 && NOTE_KIND (note) == NOTE_INSN_PROLOGUE_END)
5438 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
5440 last = NEXT_INSN (last);
5441 reorder_insns (note, note, last);
5445 if (epilogue_insn_hash != NULL)
5450 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5452 rtx insn, first = NULL, note = NULL;
5453 basic_block bb = e->src;
5455 /* Scan from the beginning until we reach the first epilogue insn. */
5456 FOR_BB_INSNS (bb, insn)
5460 if (NOTE_KIND (insn) == NOTE_INSN_EPILOGUE_BEG)
5467 else if (first == NULL && contains (insn, epilogue_insn_hash))
5477 /* If the function has a single basic block, and no real
5478 epilogue insns (e.g. sibcall with no cleanup), the
5479 epilogue note can get scheduled before the prologue
5480 note. If we have frame related prologue insns, having
5481 them scanned during the epilogue will result in a crash.
5482 In this case re-order the epilogue note to just before
5483 the last insn in the block. */
5485 first = BB_END (bb);
5487 if (PREV_INSN (first) != note)
5488 reorder_insns (note, note, PREV_INSN (first));
5492 #endif /* HAVE_prologue or HAVE_epilogue */
5495 /* Returns the name of the current function. */
5497 current_function_name (void)
5501 return lang_hooks.decl_printable_name (cfun->decl, 2);
5506 rest_of_handle_check_leaf_regs (void)
5508 #ifdef LEAF_REGISTERS
5509 current_function_uses_only_leaf_regs
5510 = optimize > 0 && only_leaf_regs_used () && leaf_function_p ();
5515 /* Insert a TYPE into the used types hash table of CFUN. */
5518 used_types_insert_helper (tree type, struct function *func)
5520 if (type != NULL && func != NULL)
5524 if (func->used_types_hash == NULL)
5525 func->used_types_hash = htab_create_ggc (37, htab_hash_pointer,
5526 htab_eq_pointer, NULL);
5527 slot = htab_find_slot (func->used_types_hash, type, INSERT);
5533 /* Given a type, insert it into the used hash table in cfun. */
5535 used_types_insert (tree t)
5537 while (POINTER_TYPE_P (t) || TREE_CODE (t) == ARRAY_TYPE)
5542 if (TYPE_NAME (t) == NULL_TREE
5543 || TYPE_NAME (t) == TYPE_NAME (TYPE_MAIN_VARIANT (t)))
5544 t = TYPE_MAIN_VARIANT (t);
5545 if (debug_info_level > DINFO_LEVEL_NONE)
5548 used_types_insert_helper (t, cfun);
5550 /* So this might be a type referenced by a global variable.
5551 Record that type so that we can later decide to emit its debug
5553 VEC_safe_push (tree, gc, types_used_by_cur_var_decl, t);
5557 /* Helper to Hash a struct types_used_by_vars_entry. */
5560 hash_types_used_by_vars_entry (const struct types_used_by_vars_entry *entry)
5562 gcc_assert (entry && entry->var_decl && entry->type);
5564 return iterative_hash_object (entry->type,
5565 iterative_hash_object (entry->var_decl, 0));
5568 /* Hash function of the types_used_by_vars_entry hash table. */
5571 types_used_by_vars_do_hash (const void *x)
5573 const struct types_used_by_vars_entry *entry =
5574 (const struct types_used_by_vars_entry *) x;
5576 return hash_types_used_by_vars_entry (entry);
5579 /*Equality function of the types_used_by_vars_entry hash table. */
5582 types_used_by_vars_eq (const void *x1, const void *x2)
5584 const struct types_used_by_vars_entry *e1 =
5585 (const struct types_used_by_vars_entry *) x1;
5586 const struct types_used_by_vars_entry *e2 =
5587 (const struct types_used_by_vars_entry *)x2;
5589 return (e1->var_decl == e2->var_decl && e1->type == e2->type);
5592 /* Inserts an entry into the types_used_by_vars_hash hash table. */
5595 types_used_by_var_decl_insert (tree type, tree var_decl)
5597 if (type != NULL && var_decl != NULL)
5600 struct types_used_by_vars_entry e;
5601 e.var_decl = var_decl;
5603 if (types_used_by_vars_hash == NULL)
5604 types_used_by_vars_hash =
5605 htab_create_ggc (37, types_used_by_vars_do_hash,
5606 types_used_by_vars_eq, NULL);
5607 slot = htab_find_slot_with_hash (types_used_by_vars_hash, &e,
5608 hash_types_used_by_vars_entry (&e), INSERT);
5611 struct types_used_by_vars_entry *entry;
5612 entry = ggc_alloc_types_used_by_vars_entry ();
5614 entry->var_decl = var_decl;
5620 struct rtl_opt_pass pass_leaf_regs =
5624 "*leaf_regs", /* name */
5626 rest_of_handle_check_leaf_regs, /* execute */
5629 0, /* static_pass_number */
5630 TV_NONE, /* tv_id */
5631 0, /* properties_required */
5632 0, /* properties_provided */
5633 0, /* properties_destroyed */
5634 0, /* todo_flags_start */
5635 0 /* todo_flags_finish */
5640 rest_of_handle_thread_prologue_and_epilogue (void)
5643 cleanup_cfg (CLEANUP_EXPENSIVE);
5644 /* On some machines, the prologue and epilogue code, or parts thereof,
5645 can be represented as RTL. Doing so lets us schedule insns between
5646 it and the rest of the code and also allows delayed branch
5647 scheduling to operate in the epilogue. */
5649 thread_prologue_and_epilogue_insns ();
5653 struct rtl_opt_pass pass_thread_prologue_and_epilogue =
5657 "pro_and_epilogue", /* name */
5659 rest_of_handle_thread_prologue_and_epilogue, /* execute */
5662 0, /* static_pass_number */
5663 TV_THREAD_PROLOGUE_AND_EPILOGUE, /* tv_id */
5664 0, /* properties_required */
5665 0, /* properties_provided */
5666 0, /* properties_destroyed */
5667 TODO_verify_flow, /* todo_flags_start */
5670 TODO_df_finish | TODO_verify_rtl_sharing |
5671 TODO_ggc_collect /* todo_flags_finish */
5676 /* This mini-pass fixes fall-out from SSA in asm statements that have
5677 in-out constraints. Say you start with
5680 asm ("": "+mr" (inout));
5683 which is transformed very early to use explicit output and match operands:
5686 asm ("": "=mr" (inout) : "0" (inout));
5689 Or, after SSA and copyprop,
5691 asm ("": "=mr" (inout_2) : "0" (inout_1));
5694 Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
5695 they represent two separate values, so they will get different pseudo
5696 registers during expansion. Then, since the two operands need to match
5697 per the constraints, but use different pseudo registers, reload can
5698 only register a reload for these operands. But reloads can only be
5699 satisfied by hardregs, not by memory, so we need a register for this
5700 reload, just because we are presented with non-matching operands.
5701 So, even though we allow memory for this operand, no memory can be
5702 used for it, just because the two operands don't match. This can
5703 cause reload failures on register-starved targets.
5705 So it's a symptom of reload not being able to use memory for reloads
5706 or, alternatively it's also a symptom of both operands not coming into
5707 reload as matching (in which case the pseudo could go to memory just
5708 fine, as the alternative allows it, and no reload would be necessary).
5709 We fix the latter problem here, by transforming
5711 asm ("": "=mr" (inout_2) : "0" (inout_1));
5716 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
5719 match_asm_constraints_1 (rtx insn, rtx *p_sets, int noutputs)
5722 bool changed = false;
5723 rtx op = SET_SRC (p_sets[0]);
5724 int ninputs = ASM_OPERANDS_INPUT_LENGTH (op);
5725 rtvec inputs = ASM_OPERANDS_INPUT_VEC (op);
5726 bool *output_matched = XALLOCAVEC (bool, noutputs);
5728 memset (output_matched, 0, noutputs * sizeof (bool));
5729 for (i = 0; i < ninputs; i++)
5731 rtx input, output, insns;
5732 const char *constraint = ASM_OPERANDS_INPUT_CONSTRAINT (op, i);
5736 if (*constraint == '%')
5739 match = strtoul (constraint, &end, 10);
5740 if (end == constraint)
5743 gcc_assert (match < noutputs);
5744 output = SET_DEST (p_sets[match]);
5745 input = RTVEC_ELT (inputs, i);
5746 /* Only do the transformation for pseudos. */
5747 if (! REG_P (output)
5748 || rtx_equal_p (output, input)
5749 || (GET_MODE (input) != VOIDmode
5750 && GET_MODE (input) != GET_MODE (output)))
5753 /* We can't do anything if the output is also used as input,
5754 as we're going to overwrite it. */
5755 for (j = 0; j < ninputs; j++)
5756 if (reg_overlap_mentioned_p (output, RTVEC_ELT (inputs, j)))
5761 /* Avoid changing the same input several times. For
5762 asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
5763 only change in once (to out1), rather than changing it
5764 first to out1 and afterwards to out2. */
5767 for (j = 0; j < noutputs; j++)
5768 if (output_matched[j] && input == SET_DEST (p_sets[j]))
5773 output_matched[match] = true;
5776 emit_move_insn (output, input);
5777 insns = get_insns ();
5779 emit_insn_before (insns, insn);
5781 /* Now replace all mentions of the input with output. We can't
5782 just replace the occurrence in inputs[i], as the register might
5783 also be used in some other input (or even in an address of an
5784 output), which would mean possibly increasing the number of
5785 inputs by one (namely 'output' in addition), which might pose
5786 a too complicated problem for reload to solve. E.g. this situation:
5788 asm ("" : "=r" (output), "=m" (input) : "0" (input))
5790 Here 'input' is used in two occurrences as input (once for the
5791 input operand, once for the address in the second output operand).
5792 If we would replace only the occurrence of the input operand (to
5793 make the matching) we would be left with this:
5796 asm ("" : "=r" (output), "=m" (input) : "0" (output))
5798 Now we suddenly have two different input values (containing the same
5799 value, but different pseudos) where we formerly had only one.
5800 With more complicated asms this might lead to reload failures
5801 which wouldn't have happen without this pass. So, iterate over
5802 all operands and replace all occurrences of the register used. */
5803 for (j = 0; j < noutputs; j++)
5804 if (!rtx_equal_p (SET_DEST (p_sets[j]), input)
5805 && reg_overlap_mentioned_p (input, SET_DEST (p_sets[j])))
5806 SET_DEST (p_sets[j]) = replace_rtx (SET_DEST (p_sets[j]),
5808 for (j = 0; j < ninputs; j++)
5809 if (reg_overlap_mentioned_p (input, RTVEC_ELT (inputs, j)))
5810 RTVEC_ELT (inputs, j) = replace_rtx (RTVEC_ELT (inputs, j),
5817 df_insn_rescan (insn);
5821 rest_of_match_asm_constraints (void)
5824 rtx insn, pat, *p_sets;
5827 if (!crtl->has_asm_statement)
5830 df_set_flags (DF_DEFER_INSN_RESCAN);
5833 FOR_BB_INSNS (bb, insn)
5838 pat = PATTERN (insn);
5839 if (GET_CODE (pat) == PARALLEL)
5840 p_sets = &XVECEXP (pat, 0, 0), noutputs = XVECLEN (pat, 0);
5841 else if (GET_CODE (pat) == SET)
5842 p_sets = &PATTERN (insn), noutputs = 1;
5846 if (GET_CODE (*p_sets) == SET
5847 && GET_CODE (SET_SRC (*p_sets)) == ASM_OPERANDS)
5848 match_asm_constraints_1 (insn, p_sets, noutputs);
5852 return TODO_df_finish;
5855 struct rtl_opt_pass pass_match_asm_constraints =
5859 "asmcons", /* name */
5861 rest_of_match_asm_constraints, /* execute */
5864 0, /* static_pass_number */
5865 TV_NONE, /* tv_id */
5866 0, /* properties_required */
5867 0, /* properties_provided */
5868 0, /* properties_destroyed */
5869 0, /* todo_flags_start */
5870 TODO_dump_func /* todo_flags_finish */
5875 #include "gt-function.h"