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 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
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"
49 #include "hard-reg-set.h"
50 #include "insn-config.h"
53 #include "basic-block.h"
58 #include "integrate.h"
59 #include "langhooks.h"
61 #include "cfglayout.h"
63 #ifndef LOCAL_ALIGNMENT
64 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
67 #ifndef STACK_ALIGNMENT_NEEDED
68 #define STACK_ALIGNMENT_NEEDED 1
71 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
73 /* Some systems use __main in a way incompatible with its use in gcc, in these
74 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
75 give the same symbol without quotes for an alternative entry point. You
76 must define both, or neither. */
78 #define NAME__MAIN "__main"
81 /* Round a value to the lowest integer less than it that is a multiple of
82 the required alignment. Avoid using division in case the value is
83 negative. Assume the alignment is a power of two. */
84 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
86 /* Similar, but round to the next highest integer that meets the
88 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
90 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
91 during rtl generation. If they are different register numbers, this is
92 always true. It may also be true if
93 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
94 generation. See fix_lexical_addr for details. */
96 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
97 #define NEED_SEPARATE_AP
100 /* Nonzero if function being compiled doesn't contain any calls
101 (ignoring the prologue and epilogue). This is set prior to
102 local register allocation and is valid for the remaining
104 int current_function_is_leaf;
106 /* Nonzero if function being compiled doesn't modify the stack pointer
107 (ignoring the prologue and epilogue). This is only valid after
108 life_analysis has run. */
109 int current_function_sp_is_unchanging;
111 /* Nonzero if the function being compiled is a leaf function which only
112 uses leaf registers. This is valid after reload (specifically after
113 sched2) and is useful only if the port defines LEAF_REGISTERS. */
114 int current_function_uses_only_leaf_regs;
116 /* Nonzero once virtual register instantiation has been done.
117 assign_stack_local uses frame_pointer_rtx when this is nonzero.
118 calls.c:emit_library_call_value_1 uses it to set up
119 post-instantiation libcalls. */
120 int virtuals_instantiated;
122 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
123 static GTY(()) int funcdef_no;
125 /* These variables hold pointers to functions to create and destroy
126 target specific, per-function data structures. */
127 struct machine_function * (*init_machine_status) (void);
129 /* The currently compiled function. */
130 struct function *cfun = 0;
132 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
133 static GTY(()) varray_type prologue;
134 static GTY(()) varray_type epilogue;
136 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
138 static GTY(()) varray_type sibcall_epilogue;
140 /* In order to evaluate some expressions, such as function calls returning
141 structures in memory, we need to temporarily allocate stack locations.
142 We record each allocated temporary in the following structure.
144 Associated with each temporary slot is a nesting level. When we pop up
145 one level, all temporaries associated with the previous level are freed.
146 Normally, all temporaries are freed after the execution of the statement
147 in which they were created. However, if we are inside a ({...}) grouping,
148 the result may be in a temporary and hence must be preserved. If the
149 result could be in a temporary, we preserve it if we can determine which
150 one it is in. If we cannot determine which temporary may contain the
151 result, all temporaries are preserved. A temporary is preserved by
152 pretending it was allocated at the previous nesting level.
154 Automatic variables are also assigned temporary slots, at the nesting
155 level where they are defined. They are marked a "kept" so that
156 free_temp_slots will not free them. */
158 struct temp_slot GTY(())
160 /* Points to next temporary slot. */
161 struct temp_slot *next;
162 /* Points to previous temporary slot. */
163 struct temp_slot *prev;
165 /* The rtx to used to reference the slot. */
167 /* The rtx used to represent the address if not the address of the
168 slot above. May be an EXPR_LIST if multiple addresses exist. */
170 /* The alignment (in bits) of the slot. */
172 /* The size, in units, of the slot. */
174 /* The type of the object in the slot, or zero if it doesn't correspond
175 to a type. We use this to determine whether a slot can be reused.
176 It can be reused if objects of the type of the new slot will always
177 conflict with objects of the type of the old slot. */
179 /* Nonzero if this temporary is currently in use. */
181 /* Nonzero if this temporary has its address taken. */
183 /* Nesting level at which this slot is being used. */
185 /* Nonzero if this should survive a call to free_temp_slots. */
187 /* The offset of the slot from the frame_pointer, including extra space
188 for alignment. This info is for combine_temp_slots. */
189 HOST_WIDE_INT base_offset;
190 /* The size of the slot, including extra space for alignment. This
191 info is for combine_temp_slots. */
192 HOST_WIDE_INT full_size;
195 /* Forward declarations. */
197 static rtx assign_stack_local_1 (enum machine_mode, HOST_WIDE_INT, int,
199 static struct temp_slot *find_temp_slot_from_address (rtx);
200 static void instantiate_decls (tree, int);
201 static void instantiate_decls_1 (tree, int);
202 static void instantiate_decl (rtx, HOST_WIDE_INT, int);
203 static rtx instantiate_new_reg (rtx, HOST_WIDE_INT *);
204 static int instantiate_virtual_regs_1 (rtx *, rtx, int);
205 static void pad_to_arg_alignment (struct args_size *, int, struct args_size *);
206 static void pad_below (struct args_size *, enum machine_mode, tree);
207 static void reorder_blocks_1 (rtx, tree, varray_type *);
208 static void reorder_fix_fragments (tree);
209 static int all_blocks (tree, tree *);
210 static tree *get_block_vector (tree, int *);
211 extern tree debug_find_var_in_block_tree (tree, tree);
212 /* We always define `record_insns' even if it's not used so that we
213 can always export `prologue_epilogue_contains'. */
214 static void record_insns (rtx, varray_type *) ATTRIBUTE_UNUSED;
215 static int contains (rtx, varray_type);
217 static void emit_return_into_block (basic_block, rtx);
219 static void purge_single_hard_subreg_set (rtx);
220 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
221 static rtx keep_stack_depressed (rtx);
223 static void prepare_function_start (tree);
224 static void do_clobber_return_reg (rtx, void *);
225 static void do_use_return_reg (rtx, void *);
226 static void instantiate_virtual_regs_lossage (rtx);
227 static void set_insn_locators (rtx, int) ATTRIBUTE_UNUSED;
229 /* Pointer to chain of `struct function' for containing functions. */
230 struct function *outer_function_chain;
232 /* Given a function decl for a containing function,
233 return the `struct function' for it. */
236 find_function_data (tree decl)
240 for (p = outer_function_chain; p; p = p->outer)
247 /* Save the current context for compilation of a nested function.
248 This is called from language-specific code. The caller should use
249 the enter_nested langhook to save any language-specific state,
250 since this function knows only about language-independent
254 push_function_context_to (tree context)
260 if (context == current_function_decl)
261 cfun->contains_functions = 1;
264 struct function *containing = find_function_data (context);
265 containing->contains_functions = 1;
270 init_dummy_function_start ();
273 p->outer = outer_function_chain;
274 outer_function_chain = p;
276 lang_hooks.function.enter_nested (p);
282 push_function_context (void)
284 push_function_context_to (current_function_decl);
287 /* Restore the last saved context, at the end of a nested function.
288 This function is called from language-specific code. */
291 pop_function_context_from (tree context ATTRIBUTE_UNUSED)
293 struct function *p = outer_function_chain;
296 outer_function_chain = p->outer;
298 current_function_decl = p->decl;
301 restore_emit_status (p);
303 lang_hooks.function.leave_nested (p);
305 /* Reset variables that have known state during rtx generation. */
306 rtx_equal_function_value_matters = 1;
307 virtuals_instantiated = 0;
308 generating_concat_p = 1;
312 pop_function_context (void)
314 pop_function_context_from (current_function_decl);
317 /* Clear out all parts of the state in F that can safely be discarded
318 after the function has been parsed, but not compiled, to let
319 garbage collection reclaim the memory. */
322 free_after_parsing (struct function *f)
324 /* f->expr->forced_labels is used by code generation. */
325 /* f->emit->regno_reg_rtx is used by code generation. */
326 /* f->varasm is used by code generation. */
327 /* f->eh->eh_return_stub_label is used by code generation. */
329 lang_hooks.function.final (f);
333 /* Clear out all parts of the state in F that can safely be discarded
334 after the function has been compiled, to let garbage collection
335 reclaim the memory. */
338 free_after_compilation (struct function *f)
346 f->x_avail_temp_slots = NULL;
347 f->x_used_temp_slots = NULL;
348 f->arg_offset_rtx = NULL;
349 f->return_rtx = NULL;
350 f->internal_arg_pointer = NULL;
351 f->x_nonlocal_goto_handler_labels = NULL;
352 f->x_return_label = NULL;
353 f->x_naked_return_label = NULL;
354 f->x_stack_slot_list = NULL;
355 f->x_tail_recursion_reentry = NULL;
356 f->x_arg_pointer_save_area = NULL;
357 f->x_parm_birth_insn = NULL;
358 f->original_arg_vector = NULL;
359 f->original_decl_initial = NULL;
360 f->epilogue_delay_list = NULL;
363 /* Allocate fixed slots in the stack frame of the current function. */
365 /* Return size needed for stack frame based on slots so far allocated in
367 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
368 the caller may have to do that. */
371 get_func_frame_size (struct function *f)
373 #ifdef FRAME_GROWS_DOWNWARD
374 return -f->x_frame_offset;
376 return f->x_frame_offset;
380 /* Return size needed for stack frame based on slots so far allocated.
381 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
382 the caller may have to do that. */
384 get_frame_size (void)
386 return get_func_frame_size (cfun);
389 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
390 with machine mode MODE.
392 ALIGN controls the amount of alignment for the address of the slot:
393 0 means according to MODE,
394 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
395 -2 means use BITS_PER_UNIT,
396 positive specifies alignment boundary in bits.
398 We do not round to stack_boundary here.
400 FUNCTION specifies the function to allocate in. */
403 assign_stack_local_1 (enum machine_mode mode, HOST_WIDE_INT size, int align,
404 struct function *function)
407 int bigend_correction = 0;
409 int frame_off, frame_alignment, frame_phase;
416 alignment = BIGGEST_ALIGNMENT;
418 alignment = GET_MODE_ALIGNMENT (mode);
420 /* Allow the target to (possibly) increase the alignment of this
422 type = lang_hooks.types.type_for_mode (mode, 0);
424 alignment = LOCAL_ALIGNMENT (type, alignment);
426 alignment /= BITS_PER_UNIT;
428 else if (align == -1)
430 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
431 size = CEIL_ROUND (size, alignment);
433 else if (align == -2)
434 alignment = 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
436 alignment = align / BITS_PER_UNIT;
438 #ifdef FRAME_GROWS_DOWNWARD
439 function->x_frame_offset -= size;
442 /* Ignore alignment we can't do with expected alignment of the boundary. */
443 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
444 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
446 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
447 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
449 /* Calculate how many bytes the start of local variables is off from
451 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
452 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
453 frame_phase = frame_off ? frame_alignment - frame_off : 0;
455 /* Round the frame offset to the specified alignment. The default is
456 to always honor requests to align the stack but a port may choose to
457 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
458 if (STACK_ALIGNMENT_NEEDED
462 /* We must be careful here, since FRAME_OFFSET might be negative and
463 division with a negative dividend isn't as well defined as we might
464 like. So we instead assume that ALIGNMENT is a power of two and
465 use logical operations which are unambiguous. */
466 #ifdef FRAME_GROWS_DOWNWARD
467 function->x_frame_offset
468 = (FLOOR_ROUND (function->x_frame_offset - frame_phase, alignment)
471 function->x_frame_offset
472 = (CEIL_ROUND (function->x_frame_offset - frame_phase, alignment)
477 /* On a big-endian machine, if we are allocating more space than we will use,
478 use the least significant bytes of those that are allocated. */
479 if (BYTES_BIG_ENDIAN && mode != BLKmode)
480 bigend_correction = size - GET_MODE_SIZE (mode);
482 /* If we have already instantiated virtual registers, return the actual
483 address relative to the frame pointer. */
484 if (function == cfun && virtuals_instantiated)
485 addr = plus_constant (frame_pointer_rtx,
487 (frame_offset + bigend_correction
488 + STARTING_FRAME_OFFSET, Pmode));
490 addr = plus_constant (virtual_stack_vars_rtx,
492 (function->x_frame_offset + bigend_correction,
495 #ifndef FRAME_GROWS_DOWNWARD
496 function->x_frame_offset += size;
499 x = gen_rtx_MEM (mode, addr);
501 function->x_stack_slot_list
502 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
507 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
511 assign_stack_local (enum machine_mode mode, HOST_WIDE_INT size, int align)
513 return assign_stack_local_1 (mode, size, align, cfun);
517 /* Removes temporary slot TEMP from LIST. */
520 cut_slot_from_list (struct temp_slot *temp, struct temp_slot **list)
523 temp->next->prev = temp->prev;
525 temp->prev->next = temp->next;
529 temp->prev = temp->next = NULL;
532 /* Inserts temporary slot TEMP to LIST. */
535 insert_slot_to_list (struct temp_slot *temp, struct temp_slot **list)
539 (*list)->prev = temp;
544 /* Returns the list of used temp slots at LEVEL. */
546 static struct temp_slot **
547 temp_slots_at_level (int level)
551 if (!used_temp_slots)
552 VARRAY_GENERIC_PTR_INIT (used_temp_slots, 3, "used_temp_slots");
554 while (level >= (int) VARRAY_ACTIVE_SIZE (used_temp_slots))
555 VARRAY_PUSH_GENERIC_PTR (used_temp_slots, NULL);
557 return (struct temp_slot **) &VARRAY_GENERIC_PTR (used_temp_slots, level);
560 /* Returns the maximal temporary slot level. */
563 max_slot_level (void)
565 if (!used_temp_slots)
568 return VARRAY_ACTIVE_SIZE (used_temp_slots) - 1;
571 /* Moves temporary slot TEMP to LEVEL. */
574 move_slot_to_level (struct temp_slot *temp, int level)
576 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
577 insert_slot_to_list (temp, temp_slots_at_level (level));
581 /* Make temporary slot TEMP available. */
584 make_slot_available (struct temp_slot *temp)
586 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
587 insert_slot_to_list (temp, &avail_temp_slots);
592 /* Allocate a temporary stack slot and record it for possible later
595 MODE is the machine mode to be given to the returned rtx.
597 SIZE is the size in units of the space required. We do no rounding here
598 since assign_stack_local will do any required rounding.
600 KEEP is 1 if this slot is to be retained after a call to
601 free_temp_slots. Automatic variables for a block are allocated
602 with this flag. KEEP is 2 if we allocate a longer term temporary,
603 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
604 if we are to allocate something at an inner level to be treated as
605 a variable in the block (e.g., a SAVE_EXPR).
607 TYPE is the type that will be used for the stack slot. */
610 assign_stack_temp_for_type (enum machine_mode mode, HOST_WIDE_INT size, int keep,
614 struct temp_slot *p, *best_p = 0, *selected = NULL, **pp;
617 /* If SIZE is -1 it means that somebody tried to allocate a temporary
618 of a variable size. */
623 align = BIGGEST_ALIGNMENT;
625 align = GET_MODE_ALIGNMENT (mode);
628 type = lang_hooks.types.type_for_mode (mode, 0);
631 align = LOCAL_ALIGNMENT (type, align);
633 /* Try to find an available, already-allocated temporary of the proper
634 mode which meets the size and alignment requirements. Choose the
635 smallest one with the closest alignment. */
636 for (p = avail_temp_slots; p; p = p->next)
638 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
639 && objects_must_conflict_p (p->type, type)
640 && (best_p == 0 || best_p->size > p->size
641 || (best_p->size == p->size && best_p->align > p->align)))
643 if (p->align == align && p->size == size)
646 cut_slot_from_list (selected, &avail_temp_slots);
654 /* Make our best, if any, the one to use. */
658 cut_slot_from_list (selected, &avail_temp_slots);
660 /* If there are enough aligned bytes left over, make them into a new
661 temp_slot so that the extra bytes don't get wasted. Do this only
662 for BLKmode slots, so that we can be sure of the alignment. */
663 if (GET_MODE (best_p->slot) == BLKmode)
665 int alignment = best_p->align / BITS_PER_UNIT;
666 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
668 if (best_p->size - rounded_size >= alignment)
670 p = ggc_alloc (sizeof (struct temp_slot));
671 p->in_use = p->addr_taken = 0;
672 p->size = best_p->size - rounded_size;
673 p->base_offset = best_p->base_offset + rounded_size;
674 p->full_size = best_p->full_size - rounded_size;
675 p->slot = gen_rtx_MEM (BLKmode,
676 plus_constant (XEXP (best_p->slot, 0),
678 p->align = best_p->align;
680 p->type = best_p->type;
681 insert_slot_to_list (p, &avail_temp_slots);
683 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
686 best_p->size = rounded_size;
687 best_p->full_size = rounded_size;
692 /* If we still didn't find one, make a new temporary. */
695 HOST_WIDE_INT frame_offset_old = frame_offset;
697 p = ggc_alloc (sizeof (struct temp_slot));
699 /* We are passing an explicit alignment request to assign_stack_local.
700 One side effect of that is assign_stack_local will not round SIZE
701 to ensure the frame offset remains suitably aligned.
703 So for requests which depended on the rounding of SIZE, we go ahead
704 and round it now. We also make sure ALIGNMENT is at least
705 BIGGEST_ALIGNMENT. */
706 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
708 p->slot = assign_stack_local (mode,
710 ? CEIL_ROUND (size, (int) align / BITS_PER_UNIT)
716 /* The following slot size computation is necessary because we don't
717 know the actual size of the temporary slot until assign_stack_local
718 has performed all the frame alignment and size rounding for the
719 requested temporary. Note that extra space added for alignment
720 can be either above or below this stack slot depending on which
721 way the frame grows. We include the extra space if and only if it
722 is above this slot. */
723 #ifdef FRAME_GROWS_DOWNWARD
724 p->size = frame_offset_old - frame_offset;
729 /* Now define the fields used by combine_temp_slots. */
730 #ifdef FRAME_GROWS_DOWNWARD
731 p->base_offset = frame_offset;
732 p->full_size = frame_offset_old - frame_offset;
734 p->base_offset = frame_offset_old;
735 p->full_size = frame_offset - frame_offset_old;
749 p->level = target_temp_slot_level;
754 p->level = var_temp_slot_level;
759 p->level = temp_slot_level;
763 pp = temp_slots_at_level (p->level);
764 insert_slot_to_list (p, pp);
766 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
767 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
768 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list);
770 /* If we know the alias set for the memory that will be used, use
771 it. If there's no TYPE, then we don't know anything about the
772 alias set for the memory. */
773 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
774 set_mem_align (slot, align);
776 /* If a type is specified, set the relevant flags. */
779 RTX_UNCHANGING_P (slot) = (lang_hooks.honor_readonly
780 && TYPE_READONLY (type));
781 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
782 MEM_SET_IN_STRUCT_P (slot, AGGREGATE_TYPE_P (type));
788 /* Allocate a temporary stack slot and record it for possible later
789 reuse. First three arguments are same as in preceding function. */
792 assign_stack_temp (enum machine_mode mode, HOST_WIDE_INT size, int keep)
794 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
797 /* Assign a temporary.
798 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
799 and so that should be used in error messages. In either case, we
800 allocate of the given type.
801 KEEP is as for assign_stack_temp.
802 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
803 it is 0 if a register is OK.
804 DONT_PROMOTE is 1 if we should not promote values in register
808 assign_temp (tree type_or_decl, int keep, int memory_required,
809 int dont_promote ATTRIBUTE_UNUSED)
812 enum machine_mode mode;
817 if (DECL_P (type_or_decl))
818 decl = type_or_decl, type = TREE_TYPE (decl);
820 decl = NULL, type = type_or_decl;
822 mode = TYPE_MODE (type);
824 unsignedp = TYPE_UNSIGNED (type);
827 if (mode == BLKmode || memory_required)
829 HOST_WIDE_INT size = int_size_in_bytes (type);
833 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
834 problems with allocating the stack space. */
838 /* Unfortunately, we don't yet know how to allocate variable-sized
839 temporaries. However, sometimes we have a fixed upper limit on
840 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
841 instead. This is the case for Chill variable-sized strings. */
842 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
843 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
844 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
845 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
847 /* If we still haven't been able to get a size, see if the language
848 can compute a maximum size. */
850 && (size_tree = lang_hooks.types.max_size (type)) != 0
851 && host_integerp (size_tree, 1))
852 size = tree_low_cst (size_tree, 1);
854 /* The size of the temporary may be too large to fit into an integer. */
855 /* ??? Not sure this should happen except for user silliness, so limit
856 this to things that aren't compiler-generated temporaries. The
857 rest of the time we'll abort in assign_stack_temp_for_type. */
858 if (decl && size == -1
859 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
861 error ("%Jsize of variable '%D' is too large", decl, decl);
865 tmp = assign_stack_temp_for_type (mode, size, keep, type);
871 mode = promote_mode (type, mode, &unsignedp, 0);
874 return gen_reg_rtx (mode);
877 /* Combine temporary stack slots which are adjacent on the stack.
879 This allows for better use of already allocated stack space. This is only
880 done for BLKmode slots because we can be sure that we won't have alignment
881 problems in this case. */
884 combine_temp_slots (void)
886 struct temp_slot *p, *q, *next, *next_q;
889 /* We can't combine slots, because the information about which slot
890 is in which alias set will be lost. */
891 if (flag_strict_aliasing)
894 /* If there are a lot of temp slots, don't do anything unless
895 high levels of optimization. */
896 if (! flag_expensive_optimizations)
897 for (p = avail_temp_slots, num_slots = 0; p; p = p->next, num_slots++)
898 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
901 for (p = avail_temp_slots; p; p = next)
907 if (GET_MODE (p->slot) != BLKmode)
910 for (q = p->next; q; q = next_q)
916 if (GET_MODE (q->slot) != BLKmode)
919 if (p->base_offset + p->full_size == q->base_offset)
921 /* Q comes after P; combine Q into P. */
923 p->full_size += q->full_size;
926 else if (q->base_offset + q->full_size == p->base_offset)
928 /* P comes after Q; combine P into Q. */
930 q->full_size += p->full_size;
935 cut_slot_from_list (q, &avail_temp_slots);
938 /* Either delete P or advance past it. */
940 cut_slot_from_list (p, &avail_temp_slots);
944 /* Find the temp slot corresponding to the object at address X. */
946 static struct temp_slot *
947 find_temp_slot_from_address (rtx x)
953 for (i = max_slot_level (); i >= 0; i--)
954 for (p = *temp_slots_at_level (i); p; p = p->next)
956 if (XEXP (p->slot, 0) == x
958 || (GET_CODE (x) == PLUS
959 && XEXP (x, 0) == virtual_stack_vars_rtx
960 && GET_CODE (XEXP (x, 1)) == CONST_INT
961 && INTVAL (XEXP (x, 1)) >= p->base_offset
962 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
965 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
966 for (next = p->address; next; next = XEXP (next, 1))
967 if (XEXP (next, 0) == x)
971 /* If we have a sum involving a register, see if it points to a temp
973 if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 0))
974 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
976 else if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 1))
977 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
983 /* Indicate that NEW is an alternate way of referring to the temp slot
984 that previously was known by OLD. */
987 update_temp_slot_address (rtx old, rtx new)
991 if (rtx_equal_p (old, new))
994 p = find_temp_slot_from_address (old);
996 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
997 is a register, see if one operand of the PLUS is a temporary
998 location. If so, NEW points into it. Otherwise, if both OLD and
999 NEW are a PLUS and if there is a register in common between them.
1000 If so, try a recursive call on those values. */
1003 if (GET_CODE (old) != PLUS)
1008 update_temp_slot_address (XEXP (old, 0), new);
1009 update_temp_slot_address (XEXP (old, 1), new);
1012 else if (GET_CODE (new) != PLUS)
1015 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
1016 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
1017 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
1018 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
1019 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
1020 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
1021 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
1022 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
1027 /* Otherwise add an alias for the temp's address. */
1028 else if (p->address == 0)
1032 if (GET_CODE (p->address) != EXPR_LIST)
1033 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1035 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1039 /* If X could be a reference to a temporary slot, mark the fact that its
1040 address was taken. */
1043 mark_temp_addr_taken (rtx x)
1045 struct temp_slot *p;
1050 /* If X is not in memory or is at a constant address, it cannot be in
1051 a temporary slot. */
1052 if (!MEM_P (x) || CONSTANT_P (XEXP (x, 0)))
1055 p = find_temp_slot_from_address (XEXP (x, 0));
1060 /* If X could be a reference to a temporary slot, mark that slot as
1061 belonging to the to one level higher than the current level. If X
1062 matched one of our slots, just mark that one. Otherwise, we can't
1063 easily predict which it is, so upgrade all of them. Kept slots
1064 need not be touched.
1066 This is called when an ({...}) construct occurs and a statement
1067 returns a value in memory. */
1070 preserve_temp_slots (rtx x)
1072 struct temp_slot *p = 0, *next;
1074 /* If there is no result, we still might have some objects whose address
1075 were taken, so we need to make sure they stay around. */
1078 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1083 move_slot_to_level (p, temp_slot_level - 1);
1089 /* If X is a register that is being used as a pointer, see if we have
1090 a temporary slot we know it points to. To be consistent with
1091 the code below, we really should preserve all non-kept slots
1092 if we can't find a match, but that seems to be much too costly. */
1093 if (REG_P (x) && REG_POINTER (x))
1094 p = find_temp_slot_from_address (x);
1096 /* If X is not in memory or is at a constant address, it cannot be in
1097 a temporary slot, but it can contain something whose address was
1099 if (p == 0 && (!MEM_P (x) || CONSTANT_P (XEXP (x, 0))))
1101 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1106 move_slot_to_level (p, temp_slot_level - 1);
1112 /* First see if we can find a match. */
1114 p = find_temp_slot_from_address (XEXP (x, 0));
1118 /* Move everything at our level whose address was taken to our new
1119 level in case we used its address. */
1120 struct temp_slot *q;
1122 if (p->level == temp_slot_level)
1124 for (q = *temp_slots_at_level (temp_slot_level); q; q = next)
1128 if (p != q && q->addr_taken)
1129 move_slot_to_level (q, temp_slot_level - 1);
1132 move_slot_to_level (p, temp_slot_level - 1);
1138 /* Otherwise, preserve all non-kept slots at this level. */
1139 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1144 move_slot_to_level (p, temp_slot_level - 1);
1148 /* Free all temporaries used so far. This is normally called at the
1149 end of generating code for a statement. */
1152 free_temp_slots (void)
1154 struct temp_slot *p, *next;
1156 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1161 make_slot_available (p);
1164 combine_temp_slots ();
1167 /* Push deeper into the nesting level for stack temporaries. */
1170 push_temp_slots (void)
1175 /* Pop a temporary nesting level. All slots in use in the current level
1179 pop_temp_slots (void)
1181 struct temp_slot *p, *next;
1183 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1186 make_slot_available (p);
1189 combine_temp_slots ();
1194 /* Initialize temporary slots. */
1197 init_temp_slots (void)
1199 /* We have not allocated any temporaries yet. */
1200 avail_temp_slots = 0;
1201 used_temp_slots = 0;
1202 temp_slot_level = 0;
1203 var_temp_slot_level = 0;
1204 target_temp_slot_level = 0;
1207 /* These routines are responsible for converting virtual register references
1208 to the actual hard register references once RTL generation is complete.
1210 The following four variables are used for communication between the
1211 routines. They contain the offsets of the virtual registers from their
1212 respective hard registers. */
1214 static int in_arg_offset;
1215 static int var_offset;
1216 static int dynamic_offset;
1217 static int out_arg_offset;
1218 static int cfa_offset;
1220 /* In most machines, the stack pointer register is equivalent to the bottom
1223 #ifndef STACK_POINTER_OFFSET
1224 #define STACK_POINTER_OFFSET 0
1227 /* If not defined, pick an appropriate default for the offset of dynamically
1228 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1229 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1231 #ifndef STACK_DYNAMIC_OFFSET
1233 /* The bottom of the stack points to the actual arguments. If
1234 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1235 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1236 stack space for register parameters is not pushed by the caller, but
1237 rather part of the fixed stack areas and hence not included in
1238 `current_function_outgoing_args_size'. Nevertheless, we must allow
1239 for it when allocating stack dynamic objects. */
1241 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
1242 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1243 ((ACCUMULATE_OUTGOING_ARGS \
1244 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
1245 + (STACK_POINTER_OFFSET)) \
1248 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1249 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
1250 + (STACK_POINTER_OFFSET))
1254 /* On most machines, the CFA coincides with the first incoming parm. */
1256 #ifndef ARG_POINTER_CFA_OFFSET
1257 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
1261 /* Convert a SET of a hard subreg to a set of the appropriate hard
1262 register. A subroutine of purge_hard_subreg_sets. */
1265 purge_single_hard_subreg_set (rtx pattern)
1267 rtx reg = SET_DEST (pattern);
1268 enum machine_mode mode = GET_MODE (SET_DEST (pattern));
1271 if (GET_CODE (reg) == SUBREG && REG_P (SUBREG_REG (reg))
1272 && REGNO (SUBREG_REG (reg)) < FIRST_PSEUDO_REGISTER)
1274 offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)),
1275 GET_MODE (SUBREG_REG (reg)),
1278 reg = SUBREG_REG (reg);
1282 if (REG_P (reg) && REGNO (reg) < FIRST_PSEUDO_REGISTER)
1284 reg = gen_rtx_REG (mode, REGNO (reg) + offset);
1285 SET_DEST (pattern) = reg;
1289 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The
1290 only such SETs that we expect to see are those left in because
1291 integrate can't handle sets of parts of a return value register.
1293 We don't use alter_subreg because we only want to eliminate subregs
1294 of hard registers. */
1297 purge_hard_subreg_sets (rtx insn)
1299 for (; insn; insn = NEXT_INSN (insn))
1303 rtx pattern = PATTERN (insn);
1304 switch (GET_CODE (pattern))
1307 if (GET_CODE (SET_DEST (pattern)) == SUBREG)
1308 purge_single_hard_subreg_set (pattern);
1313 for (j = XVECLEN (pattern, 0) - 1; j >= 0; j--)
1315 rtx inner_pattern = XVECEXP (pattern, 0, j);
1316 if (GET_CODE (inner_pattern) == SET
1317 && GET_CODE (SET_DEST (inner_pattern)) == SUBREG)
1318 purge_single_hard_subreg_set (inner_pattern);
1329 /* Pass through the INSNS of function FNDECL and convert virtual register
1330 references to hard register references. */
1333 instantiate_virtual_regs (void)
1337 /* Compute the offsets to use for this function. */
1338 in_arg_offset = FIRST_PARM_OFFSET (current_function_decl);
1339 var_offset = STARTING_FRAME_OFFSET;
1340 dynamic_offset = STACK_DYNAMIC_OFFSET (current_function_decl);
1341 out_arg_offset = STACK_POINTER_OFFSET;
1342 cfa_offset = ARG_POINTER_CFA_OFFSET (current_function_decl);
1344 /* Scan all variables and parameters of this function. For each that is
1345 in memory, instantiate all virtual registers if the result is a valid
1346 address. If not, we do it later. That will handle most uses of virtual
1347 regs on many machines. */
1348 instantiate_decls (current_function_decl, 1);
1350 /* Initialize recognition, indicating that volatile is OK. */
1353 /* Scan through all the insns, instantiating every virtual register still
1355 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
1356 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
1357 || GET_CODE (insn) == CALL_INSN)
1359 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
1360 if (INSN_DELETED_P (insn))
1362 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
1363 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1364 if (GET_CODE (insn) == CALL_INSN)
1365 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn),
1368 /* Past this point all ASM statements should match. Verify that
1369 to avoid failures later in the compilation process. */
1370 if (asm_noperands (PATTERN (insn)) >= 0
1371 && ! check_asm_operands (PATTERN (insn)))
1372 instantiate_virtual_regs_lossage (insn);
1375 /* Now instantiate the remaining register equivalences for debugging info.
1376 These will not be valid addresses. */
1377 instantiate_decls (current_function_decl, 0);
1379 /* Indicate that, from now on, assign_stack_local should use
1380 frame_pointer_rtx. */
1381 virtuals_instantiated = 1;
1384 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1385 all virtual registers in their DECL_RTL's.
1387 If VALID_ONLY, do this only if the resulting address is still valid.
1388 Otherwise, always do it. */
1391 instantiate_decls (tree fndecl, int valid_only)
1395 /* Process all parameters of the function. */
1396 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
1398 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
1399 HOST_WIDE_INT size_rtl;
1401 instantiate_decl (DECL_RTL (decl), size, valid_only);
1403 /* If the parameter was promoted, then the incoming RTL mode may be
1404 larger than the declared type size. We must use the larger of
1406 size_rtl = GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl)));
1407 size = MAX (size_rtl, size);
1408 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
1411 /* Now process all variables defined in the function or its subblocks. */
1412 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
1415 /* Subroutine of instantiate_decls: Process all decls in the given
1416 BLOCK node and all its subblocks. */
1419 instantiate_decls_1 (tree let, int valid_only)
1423 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
1424 if (DECL_RTL_SET_P (t))
1425 instantiate_decl (DECL_RTL (t),
1426 int_size_in_bytes (TREE_TYPE (t)),
1429 /* Process all subblocks. */
1430 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
1431 instantiate_decls_1 (t, valid_only);
1434 /* Subroutine of the preceding procedures: Given RTL representing a
1435 decl and the size of the object, do any instantiation required.
1437 If VALID_ONLY is nonzero, it means that the RTL should only be
1438 changed if the new address is valid. */
1441 instantiate_decl (rtx x, HOST_WIDE_INT size, int valid_only)
1443 enum machine_mode mode;
1446 /* If this is not a MEM, no need to do anything. Similarly if the
1447 address is a constant or a register that is not a virtual register. */
1449 if (x == 0 || !MEM_P (x))
1453 if (CONSTANT_P (addr)
1455 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
1456 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
1459 /* If we should only do this if the address is valid, copy the address.
1460 We need to do this so we can undo any changes that might make the
1461 address invalid. This copy is unfortunate, but probably can't be
1465 addr = copy_rtx (addr);
1467 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
1469 if (valid_only && size >= 0)
1471 unsigned HOST_WIDE_INT decl_size = size;
1473 /* Now verify that the resulting address is valid for every integer or
1474 floating-point mode up to and including SIZE bytes long. We do this
1475 since the object might be accessed in any mode and frame addresses
1478 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
1479 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
1480 mode = GET_MODE_WIDER_MODE (mode))
1481 if (! memory_address_p (mode, addr))
1484 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
1485 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
1486 mode = GET_MODE_WIDER_MODE (mode))
1487 if (! memory_address_p (mode, addr))
1491 /* Put back the address now that we have updated it and we either know
1492 it is valid or we don't care whether it is valid. */
1497 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1498 is a virtual register, return the equivalent hard register and set the
1499 offset indirectly through the pointer. Otherwise, return 0. */
1502 instantiate_new_reg (rtx x, HOST_WIDE_INT *poffset)
1505 HOST_WIDE_INT offset;
1507 if (x == virtual_incoming_args_rtx)
1508 new = arg_pointer_rtx, offset = in_arg_offset;
1509 else if (x == virtual_stack_vars_rtx)
1510 new = frame_pointer_rtx, offset = var_offset;
1511 else if (x == virtual_stack_dynamic_rtx)
1512 new = stack_pointer_rtx, offset = dynamic_offset;
1513 else if (x == virtual_outgoing_args_rtx)
1514 new = stack_pointer_rtx, offset = out_arg_offset;
1515 else if (x == virtual_cfa_rtx)
1516 new = arg_pointer_rtx, offset = cfa_offset;
1525 /* Called when instantiate_virtual_regs has failed to update the instruction.
1526 Usually this means that non-matching instruction has been emit, however for
1527 asm statements it may be the problem in the constraints. */
1529 instantiate_virtual_regs_lossage (rtx insn)
1531 if (asm_noperands (PATTERN (insn)) >= 0)
1533 error_for_asm (insn, "impossible constraint in `asm'");
1539 /* Given a pointer to a piece of rtx and an optional pointer to the
1540 containing object, instantiate any virtual registers present in it.
1542 If EXTRA_INSNS, we always do the replacement and generate
1543 any extra insns before OBJECT. If it zero, we do nothing if replacement
1546 Return 1 if we either had nothing to do or if we were able to do the
1547 needed replacement. Return 0 otherwise; we only return zero if
1548 EXTRA_INSNS is zero.
1550 We first try some simple transformations to avoid the creation of extra
1554 instantiate_virtual_regs_1 (rtx *loc, rtx object, int extra_insns)
1559 HOST_WIDE_INT offset = 0;
1565 /* Re-start here to avoid recursion in common cases. */
1572 /* We may have detected and deleted invalid asm statements. */
1573 if (object && INSN_P (object) && INSN_DELETED_P (object))
1576 code = GET_CODE (x);
1578 /* Check for some special cases. */
1596 /* We are allowed to set the virtual registers. This means that
1597 the actual register should receive the source minus the
1598 appropriate offset. This is used, for example, in the handling
1599 of non-local gotos. */
1600 if ((new = instantiate_new_reg (SET_DEST (x), &offset)) != 0)
1602 rtx src = SET_SRC (x);
1604 /* We are setting the register, not using it, so the relevant
1605 offset is the negative of the offset to use were we using
1608 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
1610 /* The only valid sources here are PLUS or REG. Just do
1611 the simplest possible thing to handle them. */
1612 if (!REG_P (src) && GET_CODE (src) != PLUS)
1614 instantiate_virtual_regs_lossage (object);
1620 temp = force_operand (src, NULL_RTX);
1623 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
1627 emit_insn_before (seq, object);
1630 if (! validate_change (object, &SET_SRC (x), temp, 0)
1632 instantiate_virtual_regs_lossage (object);
1637 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
1642 /* Handle special case of virtual register plus constant. */
1643 if (CONSTANT_P (XEXP (x, 1)))
1645 rtx old, new_offset;
1647 /* Check for (plus (plus VIRT foo) (const_int)) first. */
1648 if (GET_CODE (XEXP (x, 0)) == PLUS)
1650 if ((new = instantiate_new_reg (XEXP (XEXP (x, 0), 0), &offset)))
1652 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
1654 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
1663 #ifdef POINTERS_EXTEND_UNSIGNED
1664 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1665 we can commute the PLUS and SUBREG because pointers into the
1666 frame are well-behaved. */
1667 else if (GET_CODE (XEXP (x, 0)) == SUBREG && GET_MODE (x) == ptr_mode
1668 && GET_CODE (XEXP (x, 1)) == CONST_INT
1670 = instantiate_new_reg (SUBREG_REG (XEXP (x, 0)),
1672 && validate_change (object, loc,
1673 plus_constant (gen_lowpart (ptr_mode,
1676 + INTVAL (XEXP (x, 1))),
1680 else if ((new = instantiate_new_reg (XEXP (x, 0), &offset)) == 0)
1682 /* We know the second operand is a constant. Unless the
1683 first operand is a REG (which has been already checked),
1684 it needs to be checked. */
1685 if (!REG_P (XEXP (x, 0)))
1693 new_offset = plus_constant (XEXP (x, 1), offset);
1695 /* If the new constant is zero, try to replace the sum with just
1697 if (new_offset == const0_rtx
1698 && validate_change (object, loc, new, 0))
1701 /* Next try to replace the register and new offset.
1702 There are two changes to validate here and we can't assume that
1703 in the case of old offset equals new just changing the register
1704 will yield a valid insn. In the interests of a little efficiency,
1705 however, we only call validate change once (we don't queue up the
1706 changes and then call apply_change_group). */
1710 ? ! validate_change (object, &XEXP (x, 0), new, 0)
1711 : (XEXP (x, 0) = new,
1712 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
1720 /* Otherwise copy the new constant into a register and replace
1721 constant with that register. */
1722 temp = gen_reg_rtx (Pmode);
1724 if (validate_change (object, &XEXP (x, 1), temp, 0))
1725 emit_insn_before (gen_move_insn (temp, new_offset), object);
1728 /* If that didn't work, replace this expression with a
1729 register containing the sum. */
1732 new = gen_rtx_PLUS (Pmode, new, new_offset);
1735 temp = force_operand (new, NULL_RTX);
1739 emit_insn_before (seq, object);
1740 if (! validate_change (object, loc, temp, 0)
1741 && ! validate_replace_rtx (x, temp, object))
1743 instantiate_virtual_regs_lossage (object);
1752 /* Fall through to generic two-operand expression case. */
1758 case DIV: case UDIV:
1759 case MOD: case UMOD:
1760 case AND: case IOR: case XOR:
1761 case ROTATERT: case ROTATE:
1762 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
1764 case GE: case GT: case GEU: case GTU:
1765 case LE: case LT: case LEU: case LTU:
1766 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
1767 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
1772 /* Most cases of MEM that convert to valid addresses have already been
1773 handled by our scan of decls. The only special handling we
1774 need here is to make a copy of the rtx to ensure it isn't being
1775 shared if we have to change it to a pseudo.
1777 If the rtx is a simple reference to an address via a virtual register,
1778 it can potentially be shared. In such cases, first try to make it
1779 a valid address, which can also be shared. Otherwise, copy it and
1782 First check for common cases that need no processing. These are
1783 usually due to instantiation already being done on a previous instance
1787 if (CONSTANT_ADDRESS_P (temp)
1788 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
1789 || temp == arg_pointer_rtx
1791 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
1792 || temp == hard_frame_pointer_rtx
1794 || temp == frame_pointer_rtx)
1797 if (GET_CODE (temp) == PLUS
1798 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
1799 && (XEXP (temp, 0) == frame_pointer_rtx
1800 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
1801 || XEXP (temp, 0) == hard_frame_pointer_rtx
1803 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
1804 || XEXP (temp, 0) == arg_pointer_rtx
1809 if (temp == virtual_stack_vars_rtx
1810 || temp == virtual_incoming_args_rtx
1811 || (GET_CODE (temp) == PLUS
1812 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
1813 && (XEXP (temp, 0) == virtual_stack_vars_rtx
1814 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
1816 /* This MEM may be shared. If the substitution can be done without
1817 the need to generate new pseudos, we want to do it in place
1818 so all copies of the shared rtx benefit. The call below will
1819 only make substitutions if the resulting address is still
1822 Note that we cannot pass X as the object in the recursive call
1823 since the insn being processed may not allow all valid
1824 addresses. However, if we were not passed on object, we can
1825 only modify X without copying it if X will have a valid
1828 ??? Also note that this can still lose if OBJECT is an insn that
1829 has less restrictions on an address that some other insn.
1830 In that case, we will modify the shared address. This case
1831 doesn't seem very likely, though. One case where this could
1832 happen is in the case of a USE or CLOBBER reference, but we
1833 take care of that below. */
1835 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
1836 object ? object : x, 0))
1839 /* Otherwise make a copy and process that copy. We copy the entire
1840 RTL expression since it might be a PLUS which could also be
1842 *loc = x = copy_rtx (x);
1845 /* Fall through to generic unary operation case. */
1848 case STRICT_LOW_PART:
1850 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
1851 case SIGN_EXTEND: case ZERO_EXTEND:
1852 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
1853 case FLOAT: case FIX:
1854 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
1859 case POPCOUNT: case PARITY:
1860 /* These case either have just one operand or we know that we need not
1861 check the rest of the operands. */
1867 /* If the operand is a MEM, see if the change is a valid MEM. If not,
1868 go ahead and make the invalid one, but do it to a copy. For a REG,
1869 just make the recursive call, since there's no chance of a problem. */
1871 if ((MEM_P (XEXP (x, 0))
1872 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
1874 || (REG_P (XEXP (x, 0))
1875 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
1878 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
1883 /* Try to replace with a PLUS. If that doesn't work, compute the sum
1884 in front of this insn and substitute the temporary. */
1885 if ((new = instantiate_new_reg (x, &offset)) != 0)
1887 temp = plus_constant (new, offset);
1888 if (!validate_change (object, loc, temp, 0))
1894 temp = force_operand (temp, NULL_RTX);
1898 emit_insn_before (seq, object);
1899 if (! validate_change (object, loc, temp, 0)
1900 && ! validate_replace_rtx (x, temp, object))
1901 instantiate_virtual_regs_lossage (object);
1911 /* Scan all subexpressions. */
1912 fmt = GET_RTX_FORMAT (code);
1913 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
1916 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
1919 else if (*fmt == 'E')
1920 for (j = 0; j < XVECLEN (x, i); j++)
1921 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
1928 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
1929 This means a type for which function calls must pass an address to the
1930 function or get an address back from the function.
1931 EXP may be a type node or an expression (whose type is tested). */
1934 aggregate_value_p (tree exp, tree fntype)
1936 int i, regno, nregs;
1939 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
1942 switch (TREE_CODE (fntype))
1945 fntype = get_callee_fndecl (fntype);
1946 fntype = fntype ? TREE_TYPE (fntype) : 0;
1949 fntype = TREE_TYPE (fntype);
1954 case IDENTIFIER_NODE:
1958 /* We don't expect other rtl types here. */
1962 if (TREE_CODE (type) == VOID_TYPE)
1964 if (targetm.calls.return_in_memory (type, fntype))
1966 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
1967 and thus can't be returned in registers. */
1968 if (TREE_ADDRESSABLE (type))
1970 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
1972 /* Make sure we have suitable call-clobbered regs to return
1973 the value in; if not, we must return it in memory. */
1974 reg = hard_function_value (type, 0, 0);
1976 /* If we have something other than a REG (e.g. a PARALLEL), then assume
1981 regno = REGNO (reg);
1982 nregs = hard_regno_nregs[regno][TYPE_MODE (type)];
1983 for (i = 0; i < nregs; i++)
1984 if (! call_used_regs[regno + i])
1989 /* Return true if we should assign DECL a pseudo register; false if it
1990 should live on the local stack. */
1993 use_register_for_decl (tree decl)
1995 /* Honor volatile. */
1996 if (TREE_SIDE_EFFECTS (decl))
1999 /* Honor addressability. */
2000 if (TREE_ADDRESSABLE (decl))
2003 /* Only register-like things go in registers. */
2004 if (DECL_MODE (decl) == BLKmode)
2007 /* If -ffloat-store specified, don't put explicit float variables
2009 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
2010 propagates values across these stores, and it probably shouldn't. */
2011 if (flag_float_store && FLOAT_TYPE_P (TREE_TYPE (decl)))
2014 /* Compiler-generated temporaries can always go in registers. */
2015 if (DECL_ARTIFICIAL (decl))
2018 #ifdef NON_SAVING_SETJMP
2019 /* Protect variables not declared "register" from setjmp. */
2020 if (NON_SAVING_SETJMP
2021 && current_function_calls_setjmp
2022 && !DECL_REGISTER (decl))
2026 return (optimize || DECL_REGISTER (decl));
2029 /* Structures to communicate between the subroutines of assign_parms.
2030 The first holds data persistent across all parameters, the second
2031 is cleared out for each parameter. */
2033 struct assign_parm_data_all
2035 CUMULATIVE_ARGS args_so_far;
2036 struct args_size stack_args_size;
2037 tree function_result_decl;
2039 rtx conversion_insns;
2040 HOST_WIDE_INT pretend_args_size;
2041 HOST_WIDE_INT extra_pretend_bytes;
2042 int reg_parm_stack_space;
2045 struct assign_parm_data_one
2051 enum machine_mode nominal_mode;
2052 enum machine_mode passed_mode;
2053 enum machine_mode promoted_mode;
2054 struct locate_and_pad_arg_data locate;
2056 BOOL_BITFIELD named_arg : 1;
2057 BOOL_BITFIELD last_named : 1;
2058 BOOL_BITFIELD passed_pointer : 1;
2059 BOOL_BITFIELD on_stack : 1;
2060 BOOL_BITFIELD loaded_in_reg : 1;
2063 /* A subroutine of assign_parms. Initialize ALL. */
2066 assign_parms_initialize_all (struct assign_parm_data_all *all)
2070 memset (all, 0, sizeof (*all));
2072 fntype = TREE_TYPE (current_function_decl);
2074 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
2075 INIT_CUMULATIVE_INCOMING_ARGS (all->args_so_far, fntype, NULL_RTX);
2077 INIT_CUMULATIVE_ARGS (all->args_so_far, fntype, NULL_RTX,
2078 current_function_decl, -1);
2081 #ifdef REG_PARM_STACK_SPACE
2082 all->reg_parm_stack_space = REG_PARM_STACK_SPACE (current_function_decl);
2086 /* If ARGS contains entries with complex types, split the entry into two
2087 entries of the component type. Return a new list of substitutions are
2088 needed, else the old list. */
2091 split_complex_args (tree args)
2095 /* Before allocating memory, check for the common case of no complex. */
2096 for (p = args; p; p = TREE_CHAIN (p))
2098 tree type = TREE_TYPE (p);
2099 if (TREE_CODE (type) == COMPLEX_TYPE
2100 && targetm.calls.split_complex_arg (type))
2106 args = copy_list (args);
2108 for (p = args; p; p = TREE_CHAIN (p))
2110 tree type = TREE_TYPE (p);
2111 if (TREE_CODE (type) == COMPLEX_TYPE
2112 && targetm.calls.split_complex_arg (type))
2115 tree subtype = TREE_TYPE (type);
2117 /* Rewrite the PARM_DECL's type with its component. */
2118 TREE_TYPE (p) = subtype;
2119 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
2120 DECL_MODE (p) = VOIDmode;
2121 DECL_SIZE (p) = NULL;
2122 DECL_SIZE_UNIT (p) = NULL;
2125 /* Build a second synthetic decl. */
2126 decl = build_decl (PARM_DECL, NULL_TREE, subtype);
2127 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
2128 layout_decl (decl, 0);
2130 /* Splice it in; skip the new decl. */
2131 TREE_CHAIN (decl) = TREE_CHAIN (p);
2132 TREE_CHAIN (p) = decl;
2140 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
2141 the hidden struct return argument, and (abi willing) complex args.
2142 Return the new parameter list. */
2145 assign_parms_augmented_arg_list (struct assign_parm_data_all *all)
2147 tree fndecl = current_function_decl;
2148 tree fntype = TREE_TYPE (fndecl);
2149 tree fnargs = DECL_ARGUMENTS (fndecl);
2151 /* If struct value address is treated as the first argument, make it so. */
2152 if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
2153 && ! current_function_returns_pcc_struct
2154 && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
2156 tree type = build_pointer_type (TREE_TYPE (fntype));
2159 decl = build_decl (PARM_DECL, NULL_TREE, type);
2160 DECL_ARG_TYPE (decl) = type;
2161 DECL_ARTIFICIAL (decl) = 1;
2163 TREE_CHAIN (decl) = fnargs;
2165 all->function_result_decl = decl;
2168 all->orig_fnargs = fnargs;
2170 /* If the target wants to split complex arguments into scalars, do so. */
2171 if (targetm.calls.split_complex_arg)
2172 fnargs = split_complex_args (fnargs);
2177 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2178 data for the parameter. Incorporate ABI specifics such as pass-by-
2179 reference and type promotion. */
2182 assign_parm_find_data_types (struct assign_parm_data_all *all, tree parm,
2183 struct assign_parm_data_one *data)
2185 tree nominal_type, passed_type;
2186 enum machine_mode nominal_mode, passed_mode, promoted_mode;
2188 memset (data, 0, sizeof (*data));
2190 /* Set LAST_NAMED if this is last named arg before last anonymous args. */
2191 if (current_function_stdarg)
2194 for (tem = TREE_CHAIN (parm); tem; tem = TREE_CHAIN (tem))
2195 if (DECL_NAME (tem))
2198 data->last_named = true;
2201 /* Set NAMED_ARG if this arg should be treated as a named arg. For
2202 most machines, if this is a varargs/stdarg function, then we treat
2203 the last named arg as if it were anonymous too. */
2204 if (targetm.calls.strict_argument_naming (&all->args_so_far))
2205 data->named_arg = 1;
2207 data->named_arg = !data->last_named;
2209 nominal_type = TREE_TYPE (parm);
2210 passed_type = DECL_ARG_TYPE (parm);
2212 /* Look out for errors propagating this far. Also, if the parameter's
2213 type is void then its value doesn't matter. */
2214 if (TREE_TYPE (parm) == error_mark_node
2215 /* This can happen after weird syntax errors
2216 or if an enum type is defined among the parms. */
2217 || TREE_CODE (parm) != PARM_DECL
2218 || passed_type == NULL
2219 || VOID_TYPE_P (nominal_type))
2221 nominal_type = passed_type = void_type_node;
2222 nominal_mode = passed_mode = promoted_mode = VOIDmode;
2226 /* Find mode of arg as it is passed, and mode of arg as it should be
2227 during execution of this function. */
2228 passed_mode = TYPE_MODE (passed_type);
2229 nominal_mode = TYPE_MODE (nominal_type);
2231 /* If the parm is to be passed as a transparent union, use the type of
2232 the first field for the tests below. We have already verified that
2233 the modes are the same. */
2234 if (DECL_TRANSPARENT_UNION (parm)
2235 || (TREE_CODE (passed_type) == UNION_TYPE
2236 && TYPE_TRANSPARENT_UNION (passed_type)))
2237 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
2239 /* See if this arg was passed by invisible reference. It is if it is an
2240 object whose size depends on the contents of the object itself or if
2241 the machine requires these objects be passed that way. */
2242 if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE (passed_type))
2243 || TREE_ADDRESSABLE (passed_type)
2244 || FUNCTION_ARG_PASS_BY_REFERENCE (all->args_so_far, passed_mode,
2245 passed_type, data->named_arg)
2248 passed_type = nominal_type = build_pointer_type (passed_type);
2249 data->passed_pointer = true;
2250 passed_mode = nominal_mode = Pmode;
2252 /* See if the frontend wants to pass this by invisible reference. */
2253 else if (passed_type != nominal_type
2254 && POINTER_TYPE_P (passed_type)
2255 && TREE_TYPE (passed_type) == nominal_type)
2257 nominal_type = passed_type;
2258 data->passed_pointer = 1;
2259 passed_mode = nominal_mode = Pmode;
2262 /* Find mode as it is passed by the ABI. */
2263 promoted_mode = passed_mode;
2264 if (targetm.calls.promote_function_args (TREE_TYPE (current_function_decl)))
2266 int unsignedp = TYPE_UNSIGNED (passed_type);
2267 promoted_mode = promote_mode (passed_type, promoted_mode,
2272 data->nominal_type = nominal_type;
2273 data->passed_type = passed_type;
2274 data->nominal_mode = nominal_mode;
2275 data->passed_mode = passed_mode;
2276 data->promoted_mode = promoted_mode;
2279 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2282 assign_parms_setup_varargs (struct assign_parm_data_all *all,
2283 struct assign_parm_data_one *data, bool no_rtl)
2285 int varargs_pretend_bytes = 0;
2287 targetm.calls.setup_incoming_varargs (&all->args_so_far,
2288 data->promoted_mode,
2290 &varargs_pretend_bytes, no_rtl);
2292 /* If the back-end has requested extra stack space, record how much is
2293 needed. Do not change pretend_args_size otherwise since it may be
2294 nonzero from an earlier partial argument. */
2295 if (varargs_pretend_bytes > 0)
2296 all->pretend_args_size = varargs_pretend_bytes;
2299 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2300 the incoming location of the current parameter. */
2303 assign_parm_find_entry_rtl (struct assign_parm_data_all *all,
2304 struct assign_parm_data_one *data)
2306 HOST_WIDE_INT pretend_bytes = 0;
2310 if (data->promoted_mode == VOIDmode)
2312 data->entry_parm = data->stack_parm = const0_rtx;
2316 #ifdef FUNCTION_INCOMING_ARG
2317 entry_parm = FUNCTION_INCOMING_ARG (all->args_so_far, data->promoted_mode,
2318 data->passed_type, data->named_arg);
2320 entry_parm = FUNCTION_ARG (all->args_so_far, data->promoted_mode,
2321 data->passed_type, data->named_arg);
2324 if (entry_parm == 0)
2325 data->promoted_mode = data->passed_mode;
2327 /* Determine parm's home in the stack, in case it arrives in the stack
2328 or we should pretend it did. Compute the stack position and rtx where
2329 the argument arrives and its size.
2331 There is one complexity here: If this was a parameter that would
2332 have been passed in registers, but wasn't only because it is
2333 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2334 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2335 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2336 as it was the previous time. */
2337 in_regs = entry_parm != 0;
2338 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2341 if (!in_regs && !data->named_arg)
2343 if (targetm.calls.pretend_outgoing_varargs_named (&all->args_so_far))
2346 #ifdef FUNCTION_INCOMING_ARG
2347 tem = FUNCTION_INCOMING_ARG (all->args_so_far, data->promoted_mode,
2348 data->passed_type, true);
2350 tem = FUNCTION_ARG (all->args_so_far, data->promoted_mode,
2351 data->passed_type, true);
2353 in_regs = tem != NULL;
2357 /* If this parameter was passed both in registers and in the stack, use
2358 the copy on the stack. */
2359 if (MUST_PASS_IN_STACK (data->promoted_mode, data->passed_type))
2366 partial = FUNCTION_ARG_PARTIAL_NREGS (all->args_so_far,
2367 data->promoted_mode,
2370 data->partial = partial;
2372 /* The caller might already have allocated stack space for the
2373 register parameters. */
2374 if (partial != 0 && all->reg_parm_stack_space == 0)
2376 /* Part of this argument is passed in registers and part
2377 is passed on the stack. Ask the prologue code to extend
2378 the stack part so that we can recreate the full value.
2380 PRETEND_BYTES is the size of the registers we need to store.
2381 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2382 stack space that the prologue should allocate.
2384 Internally, gcc assumes that the argument pointer is aligned
2385 to STACK_BOUNDARY bits. This is used both for alignment
2386 optimizations (see init_emit) and to locate arguments that are
2387 aligned to more than PARM_BOUNDARY bits. We must preserve this
2388 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2389 a stack boundary. */
2391 /* We assume at most one partial arg, and it must be the first
2392 argument on the stack. */
2393 if (all->extra_pretend_bytes || all->pretend_args_size)
2396 pretend_bytes = partial * UNITS_PER_WORD;
2397 all->pretend_args_size = CEIL_ROUND (pretend_bytes, STACK_BYTES);
2399 /* We want to align relative to the actual stack pointer, so
2400 don't include this in the stack size until later. */
2401 all->extra_pretend_bytes = all->pretend_args_size;
2405 locate_and_pad_parm (data->promoted_mode, data->passed_type, in_regs,
2406 entry_parm ? data->partial : 0, current_function_decl,
2407 &all->stack_args_size, &data->locate);
2409 /* Adjust offsets to include the pretend args. */
2410 pretend_bytes = all->extra_pretend_bytes - pretend_bytes;
2411 data->locate.slot_offset.constant += pretend_bytes;
2412 data->locate.offset.constant += pretend_bytes;
2414 data->entry_parm = entry_parm;
2417 /* A subroutine of assign_parms. If there is actually space on the stack
2418 for this parm, count it in stack_args_size and return true. */
2421 assign_parm_is_stack_parm (struct assign_parm_data_all *all,
2422 struct assign_parm_data_one *data)
2424 /* Trivially true if we've no incomming register. */
2425 if (data->entry_parm == NULL)
2427 /* Also true if we're partially in registers and partially not,
2428 since we've arranged to drop the entire argument on the stack. */
2429 else if (data->partial != 0)
2431 /* Also true if the target says that it's passed in both registers
2432 and on the stack. */
2433 else if (GET_CODE (data->entry_parm) == PARALLEL
2434 && XEXP (XVECEXP (data->entry_parm, 0, 0), 0) == NULL_RTX)
2436 /* Also true if the target says that there's stack allocated for
2437 all register parameters. */
2438 else if (all->reg_parm_stack_space > 0)
2440 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2444 all->stack_args_size.constant += data->locate.size.constant;
2445 if (data->locate.size.var)
2446 ADD_PARM_SIZE (all->stack_args_size, data->locate.size.var);
2451 /* A subroutine of assign_parms. Given that this parameter is allocated
2452 stack space by the ABI, find it. */
2455 assign_parm_find_stack_rtl (tree parm, struct assign_parm_data_one *data)
2457 rtx offset_rtx, stack_parm;
2458 unsigned int align, boundary;
2460 /* If we're passing this arg using a reg, make its stack home the
2461 aligned stack slot. */
2462 if (data->entry_parm)
2463 offset_rtx = ARGS_SIZE_RTX (data->locate.slot_offset);
2465 offset_rtx = ARGS_SIZE_RTX (data->locate.offset);
2467 stack_parm = current_function_internal_arg_pointer;
2468 if (offset_rtx != const0_rtx)
2469 stack_parm = gen_rtx_PLUS (Pmode, stack_parm, offset_rtx);
2470 stack_parm = gen_rtx_MEM (data->promoted_mode, stack_parm);
2472 set_mem_attributes (stack_parm, parm, 1);
2474 boundary = FUNCTION_ARG_BOUNDARY (data->promoted_mode, data->passed_type);
2477 /* If we're padding upward, we know that the alignment of the slot
2478 is FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2479 intentionally forcing upward padding. Otherwise we have to come
2480 up with a guess at the alignment based on OFFSET_RTX. */
2481 if (data->locate.where_pad == upward || data->entry_parm)
2483 else if (GET_CODE (offset_rtx) == CONST_INT)
2485 align = INTVAL (offset_rtx) * BITS_PER_UNIT | boundary;
2486 align = align & -align;
2489 set_mem_align (stack_parm, align);
2491 if (data->entry_parm)
2492 set_reg_attrs_for_parm (data->entry_parm, stack_parm);
2494 data->stack_parm = stack_parm;
2497 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2498 always valid and contiguous. */
2501 assign_parm_adjust_entry_rtl (struct assign_parm_data_one *data)
2503 rtx entry_parm = data->entry_parm;
2504 rtx stack_parm = data->stack_parm;
2506 /* If this parm was passed part in regs and part in memory, pretend it
2507 arrived entirely in memory by pushing the register-part onto the stack.
2508 In the special case of a DImode or DFmode that is split, we could put
2509 it together in a pseudoreg directly, but for now that's not worth
2511 if (data->partial != 0)
2513 /* Handle calls that pass values in multiple non-contiguous
2514 locations. The Irix 6 ABI has examples of this. */
2515 if (GET_CODE (entry_parm) == PARALLEL)
2516 emit_group_store (validize_mem (stack_parm), entry_parm,
2518 int_size_in_bytes (data->passed_type));
2520 move_block_from_reg (REGNO (entry_parm), validize_mem (stack_parm),
2523 entry_parm = stack_parm;
2526 /* If we didn't decide this parm came in a register, by default it came
2528 else if (entry_parm == NULL)
2529 entry_parm = stack_parm;
2531 /* When an argument is passed in multiple locations, we can't make use
2532 of this information, but we can save some copying if the whole argument
2533 is passed in a single register. */
2534 else if (GET_CODE (entry_parm) == PARALLEL
2535 && data->nominal_mode != BLKmode
2536 && data->passed_mode != BLKmode)
2538 size_t i, len = XVECLEN (entry_parm, 0);
2540 for (i = 0; i < len; i++)
2541 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
2542 && REG_P (XEXP (XVECEXP (entry_parm, 0, i), 0))
2543 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
2544 == data->passed_mode)
2545 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
2547 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
2552 data->entry_parm = entry_parm;
2555 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2556 always valid and properly aligned. */
2560 assign_parm_adjust_stack_rtl (struct assign_parm_data_one *data)
2562 rtx stack_parm = data->stack_parm;
2564 /* If we can't trust the parm stack slot to be aligned enough for its
2565 ultimate type, don't use that slot after entry. We'll make another
2566 stack slot, if we need one. */
2567 if (STRICT_ALIGNMENT && stack_parm
2568 && GET_MODE_ALIGNMENT (data->nominal_mode) > MEM_ALIGN (stack_parm))
2571 /* If parm was passed in memory, and we need to convert it on entry,
2572 don't store it back in that same slot. */
2573 else if (data->entry_parm == stack_parm
2574 && data->nominal_mode != BLKmode
2575 && data->nominal_mode != data->passed_mode)
2578 data->stack_parm = stack_parm;
2581 /* A subroutine of assign_parms. Return true if the current parameter
2582 should be stored as a BLKmode in the current frame. */
2585 assign_parm_setup_block_p (struct assign_parm_data_one *data)
2587 if (data->nominal_mode == BLKmode)
2589 if (GET_CODE (data->entry_parm) == PARALLEL)
2592 #ifdef BLOCK_REG_PADDING
2593 if (data->locate.where_pad == (BYTES_BIG_ENDIAN ? upward : downward)
2594 && GET_MODE_SIZE (data->promoted_mode) < UNITS_PER_WORD)
2601 /* A subroutine of assign_parms. Arrange for the parameter to be
2602 present and valid in DATA->STACK_RTL. */
2605 assign_parm_setup_block (tree parm, struct assign_parm_data_one *data)
2607 rtx entry_parm = data->entry_parm;
2608 rtx stack_parm = data->stack_parm;
2610 /* If we've a non-block object that's nevertheless passed in parts,
2611 reconstitute it in register operations rather than on the stack. */
2612 if (GET_CODE (entry_parm) == PARALLEL
2613 && data->nominal_mode != BLKmode
2614 && XVECLEN (entry_parm, 0) > 1
2617 rtx parmreg = gen_reg_rtx (data->nominal_mode);
2619 emit_group_store (parmreg, entry_parm, data->nominal_type,
2620 int_size_in_bytes (data->nominal_type));
2621 SET_DECL_RTL (parm, parmreg);
2625 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2626 calls that pass values in multiple non-contiguous locations. */
2627 if (REG_P (entry_parm) || GET_CODE (entry_parm) == PARALLEL)
2629 HOST_WIDE_INT size = int_size_in_bytes (data->passed_type);
2630 HOST_WIDE_INT size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
2633 /* Note that we will be storing an integral number of words.
2634 So we have to be careful to ensure that we allocate an
2635 integral number of words. We do this below in the
2636 assign_stack_local if space was not allocated in the argument
2637 list. If it was, this will not work if PARM_BOUNDARY is not
2638 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2639 if it becomes a problem. Exception is when BLKmode arrives
2640 with arguments not conforming to word_mode. */
2642 if (stack_parm == 0)
2644 stack_parm = assign_stack_local (BLKmode, size_stored, 0);
2645 data->stack_parm = stack_parm;
2646 PUT_MODE (stack_parm, GET_MODE (entry_parm));
2647 set_mem_attributes (stack_parm, parm, 1);
2649 else if (GET_CODE (entry_parm) == PARALLEL)
2651 else if (size != 0 && PARM_BOUNDARY % BITS_PER_WORD != 0)
2654 mem = validize_mem (stack_parm);
2656 /* Handle values in multiple non-contiguous locations. */
2657 if (GET_CODE (entry_parm) == PARALLEL)
2658 emit_group_store (mem, entry_parm, data->passed_type, size);
2663 /* If SIZE is that of a mode no bigger than a word, just use
2664 that mode's store operation. */
2665 else if (size <= UNITS_PER_WORD)
2667 enum machine_mode mode
2668 = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
2671 #ifdef BLOCK_REG_PADDING
2672 && (size == UNITS_PER_WORD
2673 || (BLOCK_REG_PADDING (mode, data->passed_type, 1)
2674 != (BYTES_BIG_ENDIAN ? upward : downward)))
2678 rtx reg = gen_rtx_REG (mode, REGNO (entry_parm));
2679 emit_move_insn (change_address (mem, mode, 0), reg);
2682 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
2683 machine must be aligned to the left before storing
2684 to memory. Note that the previous test doesn't
2685 handle all cases (e.g. SIZE == 3). */
2686 else if (size != UNITS_PER_WORD
2687 #ifdef BLOCK_REG_PADDING
2688 && (BLOCK_REG_PADDING (mode, data->passed_type, 1)
2696 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2697 rtx reg = gen_rtx_REG (word_mode, REGNO (data->entry_parm));
2699 x = expand_shift (LSHIFT_EXPR, word_mode, reg,
2700 build_int_2 (by, 0), NULL_RTX, 1);
2701 tem = change_address (mem, word_mode, 0);
2702 emit_move_insn (tem, x);
2705 move_block_from_reg (REGNO (data->entry_parm), mem,
2706 size_stored / UNITS_PER_WORD);
2709 move_block_from_reg (REGNO (data->entry_parm), mem,
2710 size_stored / UNITS_PER_WORD);
2713 SET_DECL_RTL (parm, stack_parm);
2716 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
2717 parameter. Get it there. Perform all ABI specified conversions. */
2720 assign_parm_setup_reg (struct assign_parm_data_all *all, tree parm,
2721 struct assign_parm_data_one *data)
2724 enum machine_mode promoted_nominal_mode;
2725 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (parm));
2726 bool did_conversion = false;
2728 /* Store the parm in a pseudoregister during the function, but we may
2729 need to do it in a wider mode. */
2731 promoted_nominal_mode
2732 = promote_mode (data->nominal_type, data->nominal_mode, &unsignedp, 0);
2734 parmreg = gen_reg_rtx (promoted_nominal_mode);
2736 if (!DECL_ARTIFICIAL (parm))
2737 mark_user_reg (parmreg);
2739 /* If this was an item that we received a pointer to,
2740 set DECL_RTL appropriately. */
2741 if (data->passed_pointer)
2743 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data->passed_type)), parmreg);
2744 set_mem_attributes (x, parm, 1);
2745 SET_DECL_RTL (parm, x);
2749 SET_DECL_RTL (parm, parmreg);
2750 maybe_set_unchanging (DECL_RTL (parm), parm);
2753 /* Copy the value into the register. */
2754 if (data->nominal_mode != data->passed_mode
2755 || promoted_nominal_mode != data->promoted_mode)
2759 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
2760 mode, by the caller. We now have to convert it to
2761 NOMINAL_MODE, if different. However, PARMREG may be in
2762 a different mode than NOMINAL_MODE if it is being stored
2765 If ENTRY_PARM is a hard register, it might be in a register
2766 not valid for operating in its mode (e.g., an odd-numbered
2767 register for a DFmode). In that case, moves are the only
2768 thing valid, so we can't do a convert from there. This
2769 occurs when the calling sequence allow such misaligned
2772 In addition, the conversion may involve a call, which could
2773 clobber parameters which haven't been copied to pseudo
2774 registers yet. Therefore, we must first copy the parm to
2775 a pseudo reg here, and save the conversion until after all
2776 parameters have been moved. */
2778 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
2780 emit_move_insn (tempreg, validize_mem (data->entry_parm));
2782 push_to_sequence (all->conversion_insns);
2783 tempreg = convert_to_mode (data->nominal_mode, tempreg, unsignedp);
2785 if (GET_CODE (tempreg) == SUBREG
2786 && GET_MODE (tempreg) == data->nominal_mode
2787 && REG_P (SUBREG_REG (tempreg))
2788 && data->nominal_mode == data->passed_mode
2789 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (data->entry_parm)
2790 && GET_MODE_SIZE (GET_MODE (tempreg))
2791 < GET_MODE_SIZE (GET_MODE (data->entry_parm)))
2793 /* The argument is already sign/zero extended, so note it
2795 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
2796 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
2799 /* TREE_USED gets set erroneously during expand_assignment. */
2800 save_tree_used = TREE_USED (parm);
2801 expand_assignment (parm, make_tree (data->nominal_type, tempreg), 0);
2802 TREE_USED (parm) = save_tree_used;
2803 all->conversion_insns = get_insns ();
2806 did_conversion = true;
2809 emit_move_insn (parmreg, validize_mem (data->entry_parm));
2811 /* If we were passed a pointer but the actual value can safely live
2812 in a register, put it in one. */
2813 if (data->passed_pointer
2814 && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
2815 /* If by-reference argument was promoted, demote it. */
2816 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
2817 || use_register_for_decl (parm)))
2819 /* We can't use nominal_mode, because it will have been set to
2820 Pmode above. We must use the actual mode of the parm. */
2821 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
2822 mark_user_reg (parmreg);
2824 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
2826 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
2827 int unsigned_p = TYPE_UNSIGNED (TREE_TYPE (parm));
2829 push_to_sequence (all->conversion_insns);
2830 emit_move_insn (tempreg, DECL_RTL (parm));
2831 tempreg = convert_to_mode (GET_MODE (parmreg), tempreg, unsigned_p);
2832 emit_move_insn (parmreg, tempreg);
2833 all->conversion_insns = get_insns();
2836 did_conversion = true;
2839 emit_move_insn (parmreg, DECL_RTL (parm));
2841 SET_DECL_RTL (parm, parmreg);
2843 /* STACK_PARM is the pointer, not the parm, and PARMREG is
2845 data->stack_parm = NULL;
2848 /* If we are passed an arg by reference and it is our responsibility
2849 to make a copy, do it now.
2850 PASSED_TYPE and PASSED mode now refer to the pointer, not the
2851 original argument, so we must recreate them in the call to
2852 FUNCTION_ARG_CALLEE_COPIES. */
2853 /* ??? Later add code to handle the case that if the argument isn't
2854 modified, don't do the copy. */
2856 else if (data->passed_pointer)
2858 tree type = TREE_TYPE (data->passed_type);
2860 if (FUNCTION_ARG_CALLEE_COPIES (all->args_so_far, TYPE_MODE (type),
2861 type, data->named_arg)
2862 && !TREE_ADDRESSABLE (type))
2866 /* This sequence may involve a library call perhaps clobbering
2867 registers that haven't been copied to pseudos yet. */
2869 push_to_sequence (all->conversion_insns);
2871 if (!COMPLETE_TYPE_P (type)
2872 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
2874 /* This is a variable sized object. */
2875 copy = allocate_dynamic_stack_space (expr_size (parm), NULL_RTX,
2877 copy = gen_rtx_MEM (BLKmode, copy);
2880 copy = assign_stack_temp (TYPE_MODE (type),
2881 int_size_in_bytes (type), 1);
2882 set_mem_attributes (copy, parm, 1);
2884 store_expr (parm, copy, 0);
2885 emit_move_insn (parmreg, XEXP (copy, 0));
2886 all->conversion_insns = get_insns ();
2889 did_conversion = true;
2893 /* Mark the register as eliminable if we did no conversion and it was
2894 copied from memory at a fixed offset, and the arg pointer was not
2895 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
2896 offset formed an invalid address, such memory-equivalences as we
2897 make here would screw up life analysis for it. */
2898 if (data->nominal_mode == data->passed_mode
2900 && data->stack_parm != 0
2901 && MEM_P (data->stack_parm)
2902 && data->locate.offset.var == 0
2903 && reg_mentioned_p (virtual_incoming_args_rtx,
2904 XEXP (data->stack_parm, 0)))
2906 rtx linsn = get_last_insn ();
2909 /* Mark complex types separately. */
2910 if (GET_CODE (parmreg) == CONCAT)
2912 enum machine_mode submode
2913 = GET_MODE_INNER (GET_MODE (parmreg));
2914 int regnor = REGNO (gen_realpart (submode, parmreg));
2915 int regnoi = REGNO (gen_imagpart (submode, parmreg));
2916 rtx stackr = gen_realpart (submode, data->stack_parm);
2917 rtx stacki = gen_imagpart (submode, data->stack_parm);
2919 /* Scan backwards for the set of the real and
2921 for (sinsn = linsn; sinsn != 0;
2922 sinsn = prev_nonnote_insn (sinsn))
2924 set = single_set (sinsn);
2928 if (SET_DEST (set) == regno_reg_rtx [regnoi])
2930 = gen_rtx_EXPR_LIST (REG_EQUIV, stacki,
2932 else if (SET_DEST (set) == regno_reg_rtx [regnor])
2934 = gen_rtx_EXPR_LIST (REG_EQUIV, stackr,
2938 else if ((set = single_set (linsn)) != 0
2939 && SET_DEST (set) == parmreg)
2941 = gen_rtx_EXPR_LIST (REG_EQUIV,
2942 data->stack_parm, REG_NOTES (linsn));
2945 /* For pointer data type, suggest pointer register. */
2946 if (POINTER_TYPE_P (TREE_TYPE (parm)))
2947 mark_reg_pointer (parmreg,
2948 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
2951 /* A subroutine of assign_parms. Allocate stack space to hold the current
2952 parameter. Get it there. Perform all ABI specified conversions. */
2955 assign_parm_setup_stack (struct assign_parm_data_all *all, tree parm,
2956 struct assign_parm_data_one *data)
2958 /* Value must be stored in the stack slot STACK_PARM during function
2961 if (data->promoted_mode != data->nominal_mode)
2963 /* Conversion is required. */
2964 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
2966 emit_move_insn (tempreg, validize_mem (data->entry_parm));
2968 push_to_sequence (all->conversion_insns);
2969 data->entry_parm = convert_to_mode (data->nominal_mode, tempreg,
2970 TYPE_UNSIGNED (TREE_TYPE (parm)));
2972 if (data->stack_parm)
2973 /* ??? This may need a big-endian conversion on sparc64. */
2975 = adjust_address (data->stack_parm, data->nominal_mode, 0);
2977 all->conversion_insns = get_insns ();
2981 if (data->entry_parm != data->stack_parm)
2983 if (data->stack_parm == 0)
2986 = assign_stack_local (GET_MODE (data->entry_parm),
2987 GET_MODE_SIZE (GET_MODE (data->entry_parm)),
2989 set_mem_attributes (data->stack_parm, parm, 1);
2992 if (data->promoted_mode != data->nominal_mode)
2994 push_to_sequence (all->conversion_insns);
2995 emit_move_insn (validize_mem (data->stack_parm),
2996 validize_mem (data->entry_parm));
2997 all->conversion_insns = get_insns ();
3001 emit_move_insn (validize_mem (data->stack_parm),
3002 validize_mem (data->entry_parm));
3005 SET_DECL_RTL (parm, data->stack_parm);
3008 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
3009 undo the frobbing that we did in assign_parms_augmented_arg_list. */
3012 assign_parms_unsplit_complex (tree orig_fnargs, tree fnargs)
3016 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm))
3018 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE
3019 && targetm.calls.split_complex_arg (TREE_TYPE (parm)))
3021 rtx tmp, real, imag;
3022 enum machine_mode inner = GET_MODE_INNER (DECL_MODE (parm));
3024 real = DECL_RTL (fnargs);
3025 imag = DECL_RTL (TREE_CHAIN (fnargs));
3026 if (inner != GET_MODE (real))
3028 real = gen_lowpart_SUBREG (inner, real);
3029 imag = gen_lowpart_SUBREG (inner, imag);
3031 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3032 SET_DECL_RTL (parm, tmp);
3034 real = DECL_INCOMING_RTL (fnargs);
3035 imag = DECL_INCOMING_RTL (TREE_CHAIN (fnargs));
3036 if (inner != GET_MODE (real))
3038 real = gen_lowpart_SUBREG (inner, real);
3039 imag = gen_lowpart_SUBREG (inner, imag);
3041 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3042 set_decl_incoming_rtl (parm, tmp);
3043 fnargs = TREE_CHAIN (fnargs);
3047 SET_DECL_RTL (parm, DECL_RTL (fnargs));
3048 set_decl_incoming_rtl (parm, DECL_INCOMING_RTL (fnargs));
3050 /* Set MEM_EXPR to the original decl, i.e. to PARM,
3051 instead of the copy of decl, i.e. FNARGS. */
3052 if (DECL_INCOMING_RTL (parm) && MEM_P (DECL_INCOMING_RTL (parm)))
3053 set_mem_expr (DECL_INCOMING_RTL (parm), parm);
3056 fnargs = TREE_CHAIN (fnargs);
3060 /* Assign RTL expressions to the function's parameters. This may involve
3061 copying them into registers and using those registers as the DECL_RTL. */
3064 assign_parms (tree fndecl)
3066 struct assign_parm_data_all all;
3068 rtx internal_arg_pointer;
3069 int varargs_setup = 0;
3071 /* If the reg that the virtual arg pointer will be translated into is
3072 not a fixed reg or is the stack pointer, make a copy of the virtual
3073 arg pointer, and address parms via the copy. The frame pointer is
3074 considered fixed even though it is not marked as such.
3076 The second time through, simply use ap to avoid generating rtx. */
3078 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
3079 || ! (fixed_regs[ARG_POINTER_REGNUM]
3080 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
3081 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
3083 internal_arg_pointer = virtual_incoming_args_rtx;
3084 current_function_internal_arg_pointer = internal_arg_pointer;
3086 assign_parms_initialize_all (&all);
3087 fnargs = assign_parms_augmented_arg_list (&all);
3089 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
3091 struct assign_parm_data_one data;
3093 /* Extract the type of PARM; adjust it according to ABI. */
3094 assign_parm_find_data_types (&all, parm, &data);
3096 /* Early out for errors and void parameters. */
3097 if (data.passed_mode == VOIDmode)
3099 SET_DECL_RTL (parm, const0_rtx);
3100 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
3104 /* Handle stdargs. LAST_NAMED is a slight mis-nomer; it's also true
3105 for the unnamed dummy argument following the last named argument.
3106 See ABI silliness wrt strict_argument_naming and NAMED_ARG. So
3107 we only want to do this when we get to the actual last named
3108 argument, which will be the first time LAST_NAMED gets set. */
3109 if (data.last_named && !varargs_setup)
3111 varargs_setup = true;
3112 assign_parms_setup_varargs (&all, &data, false);
3115 /* Find out where the parameter arrives in this function. */
3116 assign_parm_find_entry_rtl (&all, &data);
3118 /* Find out where stack space for this parameter might be. */
3119 if (assign_parm_is_stack_parm (&all, &data))
3121 assign_parm_find_stack_rtl (parm, &data);
3122 assign_parm_adjust_entry_rtl (&data);
3125 /* Record permanently how this parm was passed. */
3126 set_decl_incoming_rtl (parm, data.entry_parm);
3128 /* Update info on where next arg arrives in registers. */
3129 FUNCTION_ARG_ADVANCE (all.args_so_far, data.promoted_mode,
3130 data.passed_type, data.named_arg);
3132 assign_parm_adjust_stack_rtl (&data);
3134 if (assign_parm_setup_block_p (&data))
3135 assign_parm_setup_block (parm, &data);
3136 else if (data.passed_pointer || use_register_for_decl (parm))
3137 assign_parm_setup_reg (&all, parm, &data);
3139 assign_parm_setup_stack (&all, parm, &data);
3142 if (targetm.calls.split_complex_arg && fnargs != all.orig_fnargs)
3143 assign_parms_unsplit_complex (all.orig_fnargs, fnargs);
3145 /* Output all parameter conversion instructions (possibly including calls)
3146 now that all parameters have been copied out of hard registers. */
3147 emit_insn (all.conversion_insns);
3149 /* If we are receiving a struct value address as the first argument, set up
3150 the RTL for the function result. As this might require code to convert
3151 the transmitted address to Pmode, we do this here to ensure that possible
3152 preliminary conversions of the address have been emitted already. */
3153 if (all.function_result_decl)
3155 tree result = DECL_RESULT (current_function_decl);
3156 rtx addr = DECL_RTL (all.function_result_decl);
3159 addr = convert_memory_address (Pmode, addr);
3160 x = gen_rtx_MEM (DECL_MODE (result), addr);
3161 set_mem_attributes (x, result, 1);
3162 SET_DECL_RTL (result, x);
3165 /* We have aligned all the args, so add space for the pretend args. */
3166 current_function_pretend_args_size = all.pretend_args_size;
3167 all.stack_args_size.constant += all.extra_pretend_bytes;
3168 current_function_args_size = all.stack_args_size.constant;
3170 /* Adjust function incoming argument size for alignment and
3173 #ifdef REG_PARM_STACK_SPACE
3174 current_function_args_size = MAX (current_function_args_size,
3175 REG_PARM_STACK_SPACE (fndecl));
3178 current_function_args_size
3179 = ((current_function_args_size + STACK_BYTES - 1)
3180 / STACK_BYTES) * STACK_BYTES;
3182 #ifdef ARGS_GROW_DOWNWARD
3183 current_function_arg_offset_rtx
3184 = (all.stack_args_size.var == 0 ? GEN_INT (-all.stack_args_size.constant)
3185 : expand_expr (size_diffop (all.stack_args_size.var,
3186 size_int (-all.stack_args_size.constant)),
3187 NULL_RTX, VOIDmode, 0));
3189 current_function_arg_offset_rtx = ARGS_SIZE_RTX (all.stack_args_size);
3192 /* See how many bytes, if any, of its args a function should try to pop
3195 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
3196 current_function_args_size);
3198 /* For stdarg.h function, save info about
3199 regs and stack space used by the named args. */
3201 current_function_args_info = all.args_so_far;
3203 /* Set the rtx used for the function return value. Put this in its
3204 own variable so any optimizers that need this information don't have
3205 to include tree.h. Do this here so it gets done when an inlined
3206 function gets output. */
3208 current_function_return_rtx
3209 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
3210 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
3212 /* If scalar return value was computed in a pseudo-reg, or was a named
3213 return value that got dumped to the stack, copy that to the hard
3215 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
3217 tree decl_result = DECL_RESULT (fndecl);
3218 rtx decl_rtl = DECL_RTL (decl_result);
3220 if (REG_P (decl_rtl)
3221 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
3222 : DECL_REGISTER (decl_result))
3226 #ifdef FUNCTION_OUTGOING_VALUE
3227 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
3230 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
3233 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
3234 /* The delay slot scheduler assumes that current_function_return_rtx
3235 holds the hard register containing the return value, not a
3236 temporary pseudo. */
3237 current_function_return_rtx = real_decl_rtl;
3242 /* Indicate whether REGNO is an incoming argument to the current function
3243 that was promoted to a wider mode. If so, return the RTX for the
3244 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
3245 that REGNO is promoted from and whether the promotion was signed or
3249 promoted_input_arg (unsigned int regno, enum machine_mode *pmode, int *punsignedp)
3253 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
3254 arg = TREE_CHAIN (arg))
3255 if (REG_P (DECL_INCOMING_RTL (arg))
3256 && REGNO (DECL_INCOMING_RTL (arg)) == regno
3257 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
3259 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
3260 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (arg));
3262 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
3263 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
3264 && mode != DECL_MODE (arg))
3266 *pmode = DECL_MODE (arg);
3267 *punsignedp = unsignedp;
3268 return DECL_INCOMING_RTL (arg);
3276 /* Compute the size and offset from the start of the stacked arguments for a
3277 parm passed in mode PASSED_MODE and with type TYPE.
3279 INITIAL_OFFSET_PTR points to the current offset into the stacked
3282 The starting offset and size for this parm are returned in
3283 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3284 nonzero, the offset is that of stack slot, which is returned in
3285 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3286 padding required from the initial offset ptr to the stack slot.
3288 IN_REGS is nonzero if the argument will be passed in registers. It will
3289 never be set if REG_PARM_STACK_SPACE is not defined.
3291 FNDECL is the function in which the argument was defined.
3293 There are two types of rounding that are done. The first, controlled by
3294 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
3295 list to be aligned to the specific boundary (in bits). This rounding
3296 affects the initial and starting offsets, but not the argument size.
3298 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3299 optionally rounds the size of the parm to PARM_BOUNDARY. The
3300 initial offset is not affected by this rounding, while the size always
3301 is and the starting offset may be. */
3303 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3304 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3305 callers pass in the total size of args so far as
3306 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
3309 locate_and_pad_parm (enum machine_mode passed_mode, tree type, int in_regs,
3310 int partial, tree fndecl ATTRIBUTE_UNUSED,
3311 struct args_size *initial_offset_ptr,
3312 struct locate_and_pad_arg_data *locate)
3315 enum direction where_pad;
3317 int reg_parm_stack_space = 0;
3318 int part_size_in_regs;
3320 #ifdef REG_PARM_STACK_SPACE
3321 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
3323 /* If we have found a stack parm before we reach the end of the
3324 area reserved for registers, skip that area. */
3327 if (reg_parm_stack_space > 0)
3329 if (initial_offset_ptr->var)
3331 initial_offset_ptr->var
3332 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
3333 ssize_int (reg_parm_stack_space));
3334 initial_offset_ptr->constant = 0;
3336 else if (initial_offset_ptr->constant < reg_parm_stack_space)
3337 initial_offset_ptr->constant = reg_parm_stack_space;
3340 #endif /* REG_PARM_STACK_SPACE */
3342 part_size_in_regs = 0;
3343 if (reg_parm_stack_space == 0)
3344 part_size_in_regs = ((partial * UNITS_PER_WORD)
3345 / (PARM_BOUNDARY / BITS_PER_UNIT)
3346 * (PARM_BOUNDARY / BITS_PER_UNIT));
3349 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
3350 where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
3351 boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
3352 locate->where_pad = where_pad;
3354 #ifdef ARGS_GROW_DOWNWARD
3355 locate->slot_offset.constant = -initial_offset_ptr->constant;
3356 if (initial_offset_ptr->var)
3357 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
3358 initial_offset_ptr->var);
3362 if (where_pad != none
3363 && (!host_integerp (sizetree, 1)
3364 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
3365 s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
3366 SUB_PARM_SIZE (locate->slot_offset, s2);
3369 locate->slot_offset.constant += part_size_in_regs;
3372 #ifdef REG_PARM_STACK_SPACE
3373 || REG_PARM_STACK_SPACE (fndecl) > 0
3376 pad_to_arg_alignment (&locate->slot_offset, boundary,
3377 &locate->alignment_pad);
3379 locate->size.constant = (-initial_offset_ptr->constant
3380 - locate->slot_offset.constant);
3381 if (initial_offset_ptr->var)
3382 locate->size.var = size_binop (MINUS_EXPR,
3383 size_binop (MINUS_EXPR,
3385 initial_offset_ptr->var),
3386 locate->slot_offset.var);
3388 /* Pad_below needs the pre-rounded size to know how much to pad
3390 locate->offset = locate->slot_offset;
3391 if (where_pad == downward)
3392 pad_below (&locate->offset, passed_mode, sizetree);
3394 #else /* !ARGS_GROW_DOWNWARD */
3396 #ifdef REG_PARM_STACK_SPACE
3397 || REG_PARM_STACK_SPACE (fndecl) > 0
3400 pad_to_arg_alignment (initial_offset_ptr, boundary,
3401 &locate->alignment_pad);
3402 locate->slot_offset = *initial_offset_ptr;
3404 #ifdef PUSH_ROUNDING
3405 if (passed_mode != BLKmode)
3406 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
3409 /* Pad_below needs the pre-rounded size to know how much to pad below
3410 so this must be done before rounding up. */
3411 locate->offset = locate->slot_offset;
3412 if (where_pad == downward)
3413 pad_below (&locate->offset, passed_mode, sizetree);
3415 if (where_pad != none
3416 && (!host_integerp (sizetree, 1)
3417 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
3418 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
3420 ADD_PARM_SIZE (locate->size, sizetree);
3422 locate->size.constant -= part_size_in_regs;
3423 #endif /* ARGS_GROW_DOWNWARD */
3426 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
3427 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
3430 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
3431 struct args_size *alignment_pad)
3433 tree save_var = NULL_TREE;
3434 HOST_WIDE_INT save_constant = 0;
3435 int boundary_in_bytes = boundary / BITS_PER_UNIT;
3436 HOST_WIDE_INT sp_offset = STACK_POINTER_OFFSET;
3438 #ifdef SPARC_STACK_BOUNDARY_HACK
3439 /* The sparc port has a bug. It sometimes claims a STACK_BOUNDARY
3440 higher than the real alignment of %sp. However, when it does this,
3441 the alignment of %sp+STACK_POINTER_OFFSET will be STACK_BOUNDARY.
3442 This is a temporary hack while the sparc port is fixed. */
3443 if (SPARC_STACK_BOUNDARY_HACK)
3447 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
3449 save_var = offset_ptr->var;
3450 save_constant = offset_ptr->constant;
3453 alignment_pad->var = NULL_TREE;
3454 alignment_pad->constant = 0;
3456 if (boundary > BITS_PER_UNIT)
3458 if (offset_ptr->var)
3460 tree sp_offset_tree = ssize_int (sp_offset);
3461 tree offset = size_binop (PLUS_EXPR,
3462 ARGS_SIZE_TREE (*offset_ptr),
3464 #ifdef ARGS_GROW_DOWNWARD
3465 tree rounded = round_down (offset, boundary / BITS_PER_UNIT);
3467 tree rounded = round_up (offset, boundary / BITS_PER_UNIT);
3470 offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
3471 /* ARGS_SIZE_TREE includes constant term. */
3472 offset_ptr->constant = 0;
3473 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
3474 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
3479 offset_ptr->constant = -sp_offset +
3480 #ifdef ARGS_GROW_DOWNWARD
3481 FLOOR_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
3483 CEIL_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
3485 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
3486 alignment_pad->constant = offset_ptr->constant - save_constant;
3492 pad_below (struct args_size *offset_ptr, enum machine_mode passed_mode, tree sizetree)
3494 if (passed_mode != BLKmode)
3496 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
3497 offset_ptr->constant
3498 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
3499 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
3500 - GET_MODE_SIZE (passed_mode));
3504 if (TREE_CODE (sizetree) != INTEGER_CST
3505 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
3507 /* Round the size up to multiple of PARM_BOUNDARY bits. */
3508 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
3510 ADD_PARM_SIZE (*offset_ptr, s2);
3511 SUB_PARM_SIZE (*offset_ptr, sizetree);
3516 /* Walk the tree of blocks describing the binding levels within a function
3517 and warn about variables the might be killed by setjmp or vfork.
3518 This is done after calling flow_analysis and before global_alloc
3519 clobbers the pseudo-regs to hard regs. */
3522 setjmp_vars_warning (tree block)
3526 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
3528 if (TREE_CODE (decl) == VAR_DECL
3529 && DECL_RTL_SET_P (decl)
3530 && REG_P (DECL_RTL (decl))
3531 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
3532 warning ("%Jvariable '%D' might be clobbered by `longjmp' or `vfork'",
3536 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
3537 setjmp_vars_warning (sub);
3540 /* Do the appropriate part of setjmp_vars_warning
3541 but for arguments instead of local variables. */
3544 setjmp_args_warning (void)
3547 for (decl = DECL_ARGUMENTS (current_function_decl);
3548 decl; decl = TREE_CHAIN (decl))
3549 if (DECL_RTL (decl) != 0
3550 && REG_P (DECL_RTL (decl))
3551 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
3552 warning ("%Jargument '%D' might be clobbered by `longjmp' or `vfork'",
3557 /* Convert a stack slot address ADDR for variable VAR
3558 (from a containing function)
3559 into an address valid in this function (using a static chain). */
3562 fix_lexical_addr (rtx addr, tree var)
3565 HOST_WIDE_INT displacement;
3566 tree context = decl_function_context (var);
3567 struct function *fp;
3570 /* If this is the present function, we need not do anything. */
3571 if (context == current_function_decl)
3574 fp = find_function_data (context);
3576 /* Decode given address as base reg plus displacement. */
3578 basereg = addr, displacement = 0;
3579 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
3580 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
3587 /* Use same offset, relative to appropriate static chain or argument
3589 return plus_constant (base, displacement);
3592 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
3593 and create duplicate blocks. */
3594 /* ??? Need an option to either create block fragments or to create
3595 abstract origin duplicates of a source block. It really depends
3596 on what optimization has been performed. */
3599 reorder_blocks (void)
3601 tree block = DECL_INITIAL (current_function_decl);
3602 varray_type block_stack;
3604 if (block == NULL_TREE)
3607 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
3609 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
3610 clear_block_marks (block);
3612 /* Prune the old trees away, so that they don't get in the way. */
3613 BLOCK_SUBBLOCKS (block) = NULL_TREE;
3614 BLOCK_CHAIN (block) = NULL_TREE;
3616 /* Recreate the block tree from the note nesting. */
3617 reorder_blocks_1 (get_insns (), block, &block_stack);
3618 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
3620 /* Remove deleted blocks from the block fragment chains. */
3621 reorder_fix_fragments (block);
3624 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
3627 clear_block_marks (tree block)
3631 TREE_ASM_WRITTEN (block) = 0;
3632 clear_block_marks (BLOCK_SUBBLOCKS (block));
3633 block = BLOCK_CHAIN (block);
3638 reorder_blocks_1 (rtx insns, tree current_block, varray_type *p_block_stack)
3642 for (insn = insns; insn; insn = NEXT_INSN (insn))
3644 if (GET_CODE (insn) == NOTE)
3646 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
3648 tree block = NOTE_BLOCK (insn);
3650 /* If we have seen this block before, that means it now
3651 spans multiple address regions. Create a new fragment. */
3652 if (TREE_ASM_WRITTEN (block))
3654 tree new_block = copy_node (block);
3657 origin = (BLOCK_FRAGMENT_ORIGIN (block)
3658 ? BLOCK_FRAGMENT_ORIGIN (block)
3660 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
3661 BLOCK_FRAGMENT_CHAIN (new_block)
3662 = BLOCK_FRAGMENT_CHAIN (origin);
3663 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
3665 NOTE_BLOCK (insn) = new_block;
3669 BLOCK_SUBBLOCKS (block) = 0;
3670 TREE_ASM_WRITTEN (block) = 1;
3671 /* When there's only one block for the entire function,
3672 current_block == block and we mustn't do this, it
3673 will cause infinite recursion. */
3674 if (block != current_block)
3676 BLOCK_SUPERCONTEXT (block) = current_block;
3677 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
3678 BLOCK_SUBBLOCKS (current_block) = block;
3679 current_block = block;
3681 VARRAY_PUSH_TREE (*p_block_stack, block);
3683 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
3685 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
3686 VARRAY_POP (*p_block_stack);
3687 BLOCK_SUBBLOCKS (current_block)
3688 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
3689 current_block = BLOCK_SUPERCONTEXT (current_block);
3695 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
3696 appears in the block tree, select one of the fragments to become
3697 the new origin block. */
3700 reorder_fix_fragments (tree block)
3704 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
3705 tree new_origin = NULL_TREE;
3709 if (! TREE_ASM_WRITTEN (dup_origin))
3711 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
3713 /* Find the first of the remaining fragments. There must
3714 be at least one -- the current block. */
3715 while (! TREE_ASM_WRITTEN (new_origin))
3716 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
3717 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
3720 else if (! dup_origin)
3723 /* Re-root the rest of the fragments to the new origin. In the
3724 case that DUP_ORIGIN was null, that means BLOCK was the origin
3725 of a chain of fragments and we want to remove those fragments
3726 that didn't make it to the output. */
3729 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
3734 if (TREE_ASM_WRITTEN (chain))
3736 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
3738 pp = &BLOCK_FRAGMENT_CHAIN (chain);
3740 chain = BLOCK_FRAGMENT_CHAIN (chain);
3745 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
3746 block = BLOCK_CHAIN (block);
3750 /* Reverse the order of elements in the chain T of blocks,
3751 and return the new head of the chain (old last element). */
3754 blocks_nreverse (tree t)
3756 tree prev = 0, decl, next;
3757 for (decl = t; decl; decl = next)
3759 next = BLOCK_CHAIN (decl);
3760 BLOCK_CHAIN (decl) = prev;
3766 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
3767 non-NULL, list them all into VECTOR, in a depth-first preorder
3768 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
3772 all_blocks (tree block, tree *vector)
3778 TREE_ASM_WRITTEN (block) = 0;
3780 /* Record this block. */
3782 vector[n_blocks] = block;
3786 /* Record the subblocks, and their subblocks... */
3787 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
3788 vector ? vector + n_blocks : 0);
3789 block = BLOCK_CHAIN (block);
3795 /* Return a vector containing all the blocks rooted at BLOCK. The
3796 number of elements in the vector is stored in N_BLOCKS_P. The
3797 vector is dynamically allocated; it is the caller's responsibility
3798 to call `free' on the pointer returned. */
3801 get_block_vector (tree block, int *n_blocks_p)
3805 *n_blocks_p = all_blocks (block, NULL);
3806 block_vector = xmalloc (*n_blocks_p * sizeof (tree));
3807 all_blocks (block, block_vector);
3809 return block_vector;
3812 static GTY(()) int next_block_index = 2;
3814 /* Set BLOCK_NUMBER for all the blocks in FN. */
3817 number_blocks (tree fn)
3823 /* For SDB and XCOFF debugging output, we start numbering the blocks
3824 from 1 within each function, rather than keeping a running
3826 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
3827 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
3828 next_block_index = 1;
3831 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
3833 /* The top-level BLOCK isn't numbered at all. */
3834 for (i = 1; i < n_blocks; ++i)
3835 /* We number the blocks from two. */
3836 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
3838 free (block_vector);
3843 /* If VAR is present in a subblock of BLOCK, return the subblock. */
3846 debug_find_var_in_block_tree (tree var, tree block)
3850 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
3854 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
3856 tree ret = debug_find_var_in_block_tree (var, t);
3864 /* Allocate a function structure for FNDECL and set its contents
3868 allocate_struct_function (tree fndecl)
3871 tree fntype = fndecl ? TREE_TYPE (fndecl) : NULL_TREE;
3873 cfun = ggc_alloc_cleared (sizeof (struct function));
3875 cfun->stack_alignment_needed = STACK_BOUNDARY;
3876 cfun->preferred_stack_boundary = STACK_BOUNDARY;
3878 current_function_funcdef_no = funcdef_no++;
3880 cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL;
3882 init_stmt_for_function ();
3883 init_eh_for_function ();
3885 lang_hooks.function.init (cfun);
3886 if (init_machine_status)
3887 cfun->machine = (*init_machine_status) ();
3892 DECL_STRUCT_FUNCTION (fndecl) = cfun;
3893 cfun->decl = fndecl;
3895 result = DECL_RESULT (fndecl);
3896 if (aggregate_value_p (result, fndecl))
3898 #ifdef PCC_STATIC_STRUCT_RETURN
3899 current_function_returns_pcc_struct = 1;
3901 current_function_returns_struct = 1;
3904 current_function_returns_pointer = POINTER_TYPE_P (TREE_TYPE (result));
3906 current_function_stdarg
3908 && TYPE_ARG_TYPES (fntype) != 0
3909 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
3910 != void_type_node));
3913 /* Reset cfun, and other non-struct-function variables to defaults as
3914 appropriate for emitting rtl at the start of a function. */
3917 prepare_function_start (tree fndecl)
3919 if (fndecl && DECL_STRUCT_FUNCTION (fndecl))
3920 cfun = DECL_STRUCT_FUNCTION (fndecl);
3922 allocate_struct_function (fndecl);
3924 init_varasm_status (cfun);
3927 cse_not_expected = ! optimize;
3929 /* Caller save not needed yet. */
3930 caller_save_needed = 0;
3932 /* We haven't done register allocation yet. */
3935 /* Indicate that we need to distinguish between the return value of the
3936 present function and the return value of a function being called. */
3937 rtx_equal_function_value_matters = 1;
3939 /* Indicate that we have not instantiated virtual registers yet. */
3940 virtuals_instantiated = 0;
3942 /* Indicate that we want CONCATs now. */
3943 generating_concat_p = 1;
3945 /* Indicate we have no need of a frame pointer yet. */
3946 frame_pointer_needed = 0;
3949 /* Initialize the rtl expansion mechanism so that we can do simple things
3950 like generate sequences. This is used to provide a context during global
3951 initialization of some passes. */
3953 init_dummy_function_start (void)
3955 prepare_function_start (NULL);
3958 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
3959 and initialize static variables for generating RTL for the statements
3963 init_function_start (tree subr)
3965 prepare_function_start (subr);
3967 /* Prevent ever trying to delete the first instruction of a
3968 function. Also tell final how to output a linenum before the
3969 function prologue. Note linenums could be missing, e.g. when
3970 compiling a Java .class file. */
3971 if (! DECL_IS_BUILTIN (subr))
3972 emit_line_note (DECL_SOURCE_LOCATION (subr));
3974 /* Make sure first insn is a note even if we don't want linenums.
3975 This makes sure the first insn will never be deleted.
3976 Also, final expects a note to appear there. */
3977 emit_note (NOTE_INSN_DELETED);
3979 /* Warn if this value is an aggregate type,
3980 regardless of which calling convention we are using for it. */
3981 if (warn_aggregate_return
3982 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
3983 warning ("function returns an aggregate");
3986 /* Make sure all values used by the optimization passes have sane
3989 init_function_for_compilation (void)
3993 /* No prologue/epilogue insns yet. */
3994 VARRAY_GROW (prologue, 0);
3995 VARRAY_GROW (epilogue, 0);
3996 VARRAY_GROW (sibcall_epilogue, 0);
3999 /* Expand a call to __main at the beginning of a possible main function. */
4001 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
4002 #undef HAS_INIT_SECTION
4003 #define HAS_INIT_SECTION
4007 expand_main_function (void)
4009 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
4010 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
4012 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
4016 /* Forcibly align the stack. */
4017 #ifdef STACK_GROWS_DOWNWARD
4018 tmp = expand_simple_binop (Pmode, AND, stack_pointer_rtx, GEN_INT(-align),
4019 stack_pointer_rtx, 1, OPTAB_WIDEN);
4021 tmp = expand_simple_binop (Pmode, PLUS, stack_pointer_rtx,
4022 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
4023 tmp = expand_simple_binop (Pmode, AND, tmp, GEN_INT (-align),
4024 stack_pointer_rtx, 1, OPTAB_WIDEN);
4026 if (tmp != stack_pointer_rtx)
4027 emit_move_insn (stack_pointer_rtx, tmp);
4029 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
4030 tmp = force_reg (Pmode, const0_rtx);
4031 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
4035 for (tmp = get_last_insn (); tmp; tmp = PREV_INSN (tmp))
4036 if (NOTE_P (tmp) && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_FUNCTION_BEG)
4039 emit_insn_before (seq, tmp);
4045 #ifndef HAS_INIT_SECTION
4046 emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0);
4050 /* The PENDING_SIZES represent the sizes of variable-sized types.
4051 Create RTL for the various sizes now (using temporary variables),
4052 so that we can refer to the sizes from the RTL we are generating
4053 for the current function. The PENDING_SIZES are a TREE_LIST. The
4054 TREE_VALUE of each node is a SAVE_EXPR. */
4057 expand_pending_sizes (tree pending_sizes)
4061 /* Evaluate now the sizes of any types declared among the arguments. */
4062 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
4064 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode, 0);
4065 /* Flush the queue in case this parameter declaration has
4071 /* Start the RTL for a new function, and set variables used for
4073 SUBR is the FUNCTION_DECL node.
4074 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4075 the function's parameters, which must be run at any return statement. */
4078 expand_function_start (tree subr)
4080 /* Make sure volatile mem refs aren't considered
4081 valid operands of arithmetic insns. */
4082 init_recog_no_volatile ();
4084 current_function_profile
4086 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
4088 current_function_limit_stack
4089 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
4091 /* Make the label for return statements to jump to. Do not special
4092 case machines with special return instructions -- they will be
4093 handled later during jump, ifcvt, or epilogue creation. */
4094 return_label = gen_label_rtx ();
4096 /* Initialize rtx used to return the value. */
4097 /* Do this before assign_parms so that we copy the struct value address
4098 before any library calls that assign parms might generate. */
4100 /* Decide whether to return the value in memory or in a register. */
4101 if (aggregate_value_p (DECL_RESULT (subr), subr))
4103 /* Returning something that won't go in a register. */
4104 rtx value_address = 0;
4106 #ifdef PCC_STATIC_STRUCT_RETURN
4107 if (current_function_returns_pcc_struct)
4109 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
4110 value_address = assemble_static_space (size);
4115 rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 1);
4116 /* Expect to be passed the address of a place to store the value.
4117 If it is passed as an argument, assign_parms will take care of
4121 value_address = gen_reg_rtx (Pmode);
4122 emit_move_insn (value_address, sv);
4127 rtx x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
4128 set_mem_attributes (x, DECL_RESULT (subr), 1);
4129 SET_DECL_RTL (DECL_RESULT (subr), x);
4132 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
4133 /* If return mode is void, this decl rtl should not be used. */
4134 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
4137 /* Compute the return values into a pseudo reg, which we will copy
4138 into the true return register after the cleanups are done. */
4140 /* In order to figure out what mode to use for the pseudo, we
4141 figure out what the mode of the eventual return register will
4142 actually be, and use that. */
4144 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
4147 /* Structures that are returned in registers are not aggregate_value_p,
4148 so we may see a PARALLEL or a REG. */
4149 if (REG_P (hard_reg))
4150 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg)));
4151 else if (GET_CODE (hard_reg) == PARALLEL)
4152 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
4156 /* Set DECL_REGISTER flag so that expand_function_end will copy the
4157 result to the real return register(s). */
4158 DECL_REGISTER (DECL_RESULT (subr)) = 1;
4161 /* Initialize rtx for parameters and local variables.
4162 In some cases this requires emitting insns. */
4163 assign_parms (subr);
4165 /* If function gets a static chain arg, store it. */
4166 if (cfun->static_chain_decl)
4168 tree parm = cfun->static_chain_decl;
4169 rtx local = gen_reg_rtx (Pmode);
4171 set_decl_incoming_rtl (parm, static_chain_incoming_rtx);
4172 SET_DECL_RTL (parm, local);
4173 maybe_set_unchanging (local, parm);
4174 mark_reg_pointer (local, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
4176 emit_move_insn (local, static_chain_incoming_rtx);
4179 /* If the function receives a non-local goto, then store the
4180 bits we need to restore the frame pointer. */
4181 if (cfun->nonlocal_goto_save_area)
4186 /* ??? We need to do this save early. Unfortunately here is
4187 before the frame variable gets declared. Help out... */
4188 expand_var (TREE_OPERAND (cfun->nonlocal_goto_save_area, 0));
4190 t_save = build (ARRAY_REF, ptr_type_node, cfun->nonlocal_goto_save_area,
4191 integer_zero_node, NULL_TREE, NULL_TREE);
4192 r_save = expand_expr (t_save, NULL_RTX, VOIDmode, EXPAND_WRITE);
4194 emit_move_insn (r_save, virtual_stack_vars_rtx);
4195 update_nonlocal_goto_save_area ();
4198 /* The following was moved from init_function_start.
4199 The move is supposed to make sdb output more accurate. */
4200 /* Indicate the beginning of the function body,
4201 as opposed to parm setup. */
4202 emit_note (NOTE_INSN_FUNCTION_BEG);
4204 if (GET_CODE (get_last_insn ()) != NOTE)
4205 emit_note (NOTE_INSN_DELETED);
4206 parm_birth_insn = get_last_insn ();
4208 if (current_function_profile)
4211 PROFILE_HOOK (current_function_funcdef_no);
4215 /* After the display initializations is where the tail-recursion label
4216 should go, if we end up needing one. Ensure we have a NOTE here
4217 since some things (like trampolines) get placed before this. */
4218 tail_recursion_reentry = emit_note (NOTE_INSN_DELETED);
4220 /* Evaluate now the sizes of any types declared among the arguments. */
4221 expand_pending_sizes (nreverse (get_pending_sizes ()));
4223 /* Make sure there is a line number after the function entry setup code. */
4224 force_next_line_note ();
4227 /* Undo the effects of init_dummy_function_start. */
4229 expand_dummy_function_end (void)
4231 /* End any sequences that failed to be closed due to syntax errors. */
4232 while (in_sequence_p ())
4235 /* Outside function body, can't compute type's actual size
4236 until next function's body starts. */
4238 free_after_parsing (cfun);
4239 free_after_compilation (cfun);
4243 /* Call DOIT for each hard register used as a return value from
4244 the current function. */
4247 diddle_return_value (void (*doit) (rtx, void *), void *arg)
4249 rtx outgoing = current_function_return_rtx;
4254 if (REG_P (outgoing))
4255 (*doit) (outgoing, arg);
4256 else if (GET_CODE (outgoing) == PARALLEL)
4260 for (i = 0; i < XVECLEN (outgoing, 0); i++)
4262 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
4264 if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER)
4271 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
4273 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
4277 clobber_return_register (void)
4279 diddle_return_value (do_clobber_return_reg, NULL);
4281 /* In case we do use pseudo to return value, clobber it too. */
4282 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
4284 tree decl_result = DECL_RESULT (current_function_decl);
4285 rtx decl_rtl = DECL_RTL (decl_result);
4286 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
4288 do_clobber_return_reg (decl_rtl, NULL);
4294 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
4296 emit_insn (gen_rtx_USE (VOIDmode, reg));
4300 use_return_register (void)
4302 diddle_return_value (do_use_return_reg, NULL);
4305 /* Possibly warn about unused parameters. */
4307 do_warn_unused_parameter (tree fn)
4311 for (decl = DECL_ARGUMENTS (fn);
4312 decl; decl = TREE_CHAIN (decl))
4313 if (!TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
4314 && DECL_NAME (decl) && !DECL_ARTIFICIAL (decl))
4315 warning ("%Junused parameter '%D'", decl, decl);
4318 static GTY(()) rtx initial_trampoline;
4320 /* Generate RTL for the end of the current function. */
4323 expand_function_end (void)
4327 finish_expr_for_function ();
4329 /* If arg_pointer_save_area was referenced only from a nested
4330 function, we will not have initialized it yet. Do that now. */
4331 if (arg_pointer_save_area && ! cfun->arg_pointer_save_area_init)
4332 get_arg_pointer_save_area (cfun);
4334 /* If we are doing stack checking and this function makes calls,
4335 do a stack probe at the start of the function to ensure we have enough
4336 space for another stack frame. */
4337 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
4341 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4342 if (GET_CODE (insn) == CALL_INSN)
4345 probe_stack_range (STACK_CHECK_PROTECT,
4346 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
4349 emit_insn_before (seq, tail_recursion_reentry);
4354 /* Possibly warn about unused parameters.
4355 When frontend does unit-at-a-time, the warning is already
4356 issued at finalization time. */
4357 if (warn_unused_parameter
4358 && !lang_hooks.callgraph.expand_function)
4359 do_warn_unused_parameter (current_function_decl);
4361 /* End any sequences that failed to be closed due to syntax errors. */
4362 while (in_sequence_p ())
4365 clear_pending_stack_adjust ();
4366 do_pending_stack_adjust ();
4368 /* @@@ This is a kludge. We want to ensure that instructions that
4369 may trap are not moved into the epilogue by scheduling, because
4370 we don't always emit unwind information for the epilogue.
4371 However, not all machine descriptions define a blockage insn, so
4372 emit an ASM_INPUT to act as one. */
4373 if (flag_non_call_exceptions)
4374 emit_insn (gen_rtx_ASM_INPUT (VOIDmode, ""));
4376 /* Mark the end of the function body.
4377 If control reaches this insn, the function can drop through
4378 without returning a value. */
4379 emit_note (NOTE_INSN_FUNCTION_END);
4381 /* Must mark the last line number note in the function, so that the test
4382 coverage code can avoid counting the last line twice. This just tells
4383 the code to ignore the immediately following line note, since there
4384 already exists a copy of this note somewhere above. This line number
4385 note is still needed for debugging though, so we can't delete it. */
4386 if (flag_test_coverage)
4387 emit_note (NOTE_INSN_REPEATED_LINE_NUMBER);
4389 /* Output a linenumber for the end of the function.
4390 SDB depends on this. */
4391 force_next_line_note ();
4392 emit_line_note (input_location);
4394 /* Before the return label (if any), clobber the return
4395 registers so that they are not propagated live to the rest of
4396 the function. This can only happen with functions that drop
4397 through; if there had been a return statement, there would
4398 have either been a return rtx, or a jump to the return label.
4400 We delay actual code generation after the current_function_value_rtx
4402 clobber_after = get_last_insn ();
4404 /* Output the label for the actual return from the function,
4405 if one is expected. This happens either because a function epilogue
4406 is used instead of a return instruction, or because a return was done
4407 with a goto in order to run local cleanups, or because of pcc-style
4408 structure returning. */
4410 emit_label (return_label);
4412 /* Let except.c know where it should emit the call to unregister
4413 the function context for sjlj exceptions. */
4414 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
4415 sjlj_emit_function_exit_after (get_last_insn ());
4417 /* If we had calls to alloca, and this machine needs
4418 an accurate stack pointer to exit the function,
4419 insert some code to save and restore the stack pointer. */
4420 if (! EXIT_IGNORE_STACK
4421 && current_function_calls_alloca)
4425 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
4426 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
4429 /* If scalar return value was computed in a pseudo-reg, or was a named
4430 return value that got dumped to the stack, copy that to the hard
4432 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
4434 tree decl_result = DECL_RESULT (current_function_decl);
4435 rtx decl_rtl = DECL_RTL (decl_result);
4437 if (REG_P (decl_rtl)
4438 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
4439 : DECL_REGISTER (decl_result))
4441 rtx real_decl_rtl = current_function_return_rtx;
4443 /* This should be set in assign_parms. */
4444 if (! REG_FUNCTION_VALUE_P (real_decl_rtl))
4447 /* If this is a BLKmode structure being returned in registers,
4448 then use the mode computed in expand_return. Note that if
4449 decl_rtl is memory, then its mode may have been changed,
4450 but that current_function_return_rtx has not. */
4451 if (GET_MODE (real_decl_rtl) == BLKmode)
4452 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
4454 /* If a named return value dumped decl_return to memory, then
4455 we may need to re-do the PROMOTE_MODE signed/unsigned
4457 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
4459 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (decl_result));
4461 if (targetm.calls.promote_function_return (TREE_TYPE (current_function_decl)))
4462 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
4465 convert_move (real_decl_rtl, decl_rtl, unsignedp);
4467 else if (GET_CODE (real_decl_rtl) == PARALLEL)
4469 /* If expand_function_start has created a PARALLEL for decl_rtl,
4470 move the result to the real return registers. Otherwise, do
4471 a group load from decl_rtl for a named return. */
4472 if (GET_CODE (decl_rtl) == PARALLEL)
4473 emit_group_move (real_decl_rtl, decl_rtl);
4475 emit_group_load (real_decl_rtl, decl_rtl,
4476 TREE_TYPE (decl_result),
4477 int_size_in_bytes (TREE_TYPE (decl_result)));
4480 emit_move_insn (real_decl_rtl, decl_rtl);
4484 /* If returning a structure, arrange to return the address of the value
4485 in a place where debuggers expect to find it.
4487 If returning a structure PCC style,
4488 the caller also depends on this value.
4489 And current_function_returns_pcc_struct is not necessarily set. */
4490 if (current_function_returns_struct
4491 || current_function_returns_pcc_struct)
4494 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
4495 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
4496 #ifdef FUNCTION_OUTGOING_VALUE
4498 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
4499 current_function_decl);
4502 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
4505 /* Mark this as a function return value so integrate will delete the
4506 assignment and USE below when inlining this function. */
4507 REG_FUNCTION_VALUE_P (outgoing) = 1;
4509 /* The address may be ptr_mode and OUTGOING may be Pmode. */
4510 value_address = convert_memory_address (GET_MODE (outgoing),
4513 emit_move_insn (outgoing, value_address);
4515 /* Show return register used to hold result (in this case the address
4517 current_function_return_rtx = outgoing;
4520 /* If this is an implementation of throw, do what's necessary to
4521 communicate between __builtin_eh_return and the epilogue. */
4522 expand_eh_return ();
4524 /* Emit the actual code to clobber return register. */
4529 clobber_return_register ();
4533 after = emit_insn_after (seq, clobber_after);
4536 /* Output the label for the naked return from the function, if one is
4537 expected. This is currently used only by __builtin_return. */
4538 if (naked_return_label)
4539 emit_label (naked_return_label);
4541 /* ??? This should no longer be necessary since stupid is no longer with
4542 us, but there are some parts of the compiler (eg reload_combine, and
4543 sh mach_dep_reorg) that still try and compute their own lifetime info
4544 instead of using the general framework. */
4545 use_return_register ();
4549 get_arg_pointer_save_area (struct function *f)
4551 rtx ret = f->x_arg_pointer_save_area;
4555 ret = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, f);
4556 f->x_arg_pointer_save_area = ret;
4559 if (f == cfun && ! f->arg_pointer_save_area_init)
4563 /* Save the arg pointer at the beginning of the function. The
4564 generated stack slot may not be a valid memory address, so we
4565 have to check it and fix it if necessary. */
4567 emit_move_insn (validize_mem (ret), virtual_incoming_args_rtx);
4571 push_topmost_sequence ();
4572 emit_insn_after (seq, get_insns ());
4573 pop_topmost_sequence ();
4579 /* Extend a vector that records the INSN_UIDs of INSNS
4580 (a list of one or more insns). */
4583 record_insns (rtx insns, varray_type *vecp)
4590 while (tmp != NULL_RTX)
4593 tmp = NEXT_INSN (tmp);
4596 i = VARRAY_SIZE (*vecp);
4597 VARRAY_GROW (*vecp, i + len);
4599 while (tmp != NULL_RTX)
4601 VARRAY_INT (*vecp, i) = INSN_UID (tmp);
4603 tmp = NEXT_INSN (tmp);
4607 /* Set the locator of the insn chain starting at INSN to LOC. */
4609 set_insn_locators (rtx insn, int loc)
4611 while (insn != NULL_RTX)
4614 INSN_LOCATOR (insn) = loc;
4615 insn = NEXT_INSN (insn);
4619 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
4620 be running after reorg, SEQUENCE rtl is possible. */
4623 contains (rtx insn, varray_type vec)
4627 if (GET_CODE (insn) == INSN
4628 && GET_CODE (PATTERN (insn)) == SEQUENCE)
4631 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
4632 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
4633 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
4639 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
4640 if (INSN_UID (insn) == VARRAY_INT (vec, j))
4647 prologue_epilogue_contains (rtx insn)
4649 if (contains (insn, prologue))
4651 if (contains (insn, epilogue))
4657 sibcall_epilogue_contains (rtx insn)
4659 if (sibcall_epilogue)
4660 return contains (insn, sibcall_epilogue);
4665 /* Insert gen_return at the end of block BB. This also means updating
4666 block_for_insn appropriately. */
4669 emit_return_into_block (basic_block bb, rtx line_note)
4671 emit_jump_insn_after (gen_return (), BB_END (bb));
4673 emit_note_copy_after (line_note, PREV_INSN (BB_END (bb)));
4675 #endif /* HAVE_return */
4677 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
4679 /* These functions convert the epilogue into a variant that does not modify the
4680 stack pointer. This is used in cases where a function returns an object
4681 whose size is not known until it is computed. The called function leaves the
4682 object on the stack, leaves the stack depressed, and returns a pointer to
4685 What we need to do is track all modifications and references to the stack
4686 pointer, deleting the modifications and changing the references to point to
4687 the location the stack pointer would have pointed to had the modifications
4690 These functions need to be portable so we need to make as few assumptions
4691 about the epilogue as we can. However, the epilogue basically contains
4692 three things: instructions to reset the stack pointer, instructions to
4693 reload registers, possibly including the frame pointer, and an
4694 instruction to return to the caller.
4696 If we can't be sure of what a relevant epilogue insn is doing, we abort.
4697 We also make no attempt to validate the insns we make since if they are
4698 invalid, we probably can't do anything valid. The intent is that these
4699 routines get "smarter" as more and more machines start to use them and
4700 they try operating on different epilogues.
4702 We use the following structure to track what the part of the epilogue that
4703 we've already processed has done. We keep two copies of the SP equivalence,
4704 one for use during the insn we are processing and one for use in the next
4705 insn. The difference is because one part of a PARALLEL may adjust SP
4706 and the other may use it. */
4710 rtx sp_equiv_reg; /* REG that SP is set from, perhaps SP. */
4711 HOST_WIDE_INT sp_offset; /* Offset from SP_EQUIV_REG of present SP. */
4712 rtx new_sp_equiv_reg; /* REG to be used at end of insn. */
4713 HOST_WIDE_INT new_sp_offset; /* Offset to be used at end of insn. */
4714 rtx equiv_reg_src; /* If nonzero, the value that SP_EQUIV_REG
4715 should be set to once we no longer need
4717 rtx const_equiv[FIRST_PSEUDO_REGISTER]; /* Any known constant equivalences
4721 static void handle_epilogue_set (rtx, struct epi_info *);
4722 static void update_epilogue_consts (rtx, rtx, void *);
4723 static void emit_equiv_load (struct epi_info *);
4725 /* Modify INSN, a list of one or more insns that is part of the epilogue, to
4726 no modifications to the stack pointer. Return the new list of insns. */
4729 keep_stack_depressed (rtx insns)
4732 struct epi_info info;
4735 /* If the epilogue is just a single instruction, it must be OK as is. */
4736 if (NEXT_INSN (insns) == NULL_RTX)
4739 /* Otherwise, start a sequence, initialize the information we have, and
4740 process all the insns we were given. */
4743 info.sp_equiv_reg = stack_pointer_rtx;
4745 info.equiv_reg_src = 0;
4747 for (j = 0; j < FIRST_PSEUDO_REGISTER; j++)
4748 info.const_equiv[j] = 0;
4752 while (insn != NULL_RTX)
4754 next = NEXT_INSN (insn);
4763 /* If this insn references the register that SP is equivalent to and
4764 we have a pending load to that register, we must force out the load
4765 first and then indicate we no longer know what SP's equivalent is. */
4766 if (info.equiv_reg_src != 0
4767 && reg_referenced_p (info.sp_equiv_reg, PATTERN (insn)))
4769 emit_equiv_load (&info);
4770 info.sp_equiv_reg = 0;
4773 info.new_sp_equiv_reg = info.sp_equiv_reg;
4774 info.new_sp_offset = info.sp_offset;
4776 /* If this is a (RETURN) and the return address is on the stack,
4777 update the address and change to an indirect jump. */
4778 if (GET_CODE (PATTERN (insn)) == RETURN
4779 || (GET_CODE (PATTERN (insn)) == PARALLEL
4780 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == RETURN))
4782 rtx retaddr = INCOMING_RETURN_ADDR_RTX;
4784 HOST_WIDE_INT offset = 0;
4785 rtx jump_insn, jump_set;
4787 /* If the return address is in a register, we can emit the insn
4788 unchanged. Otherwise, it must be a MEM and we see what the
4789 base register and offset are. In any case, we have to emit any
4790 pending load to the equivalent reg of SP, if any. */
4791 if (REG_P (retaddr))
4793 emit_equiv_load (&info);
4798 else if (MEM_P (retaddr)
4799 && REG_P (XEXP (retaddr, 0)))
4800 base = gen_rtx_REG (Pmode, REGNO (XEXP (retaddr, 0))), offset = 0;
4801 else if (MEM_P (retaddr)
4802 && GET_CODE (XEXP (retaddr, 0)) == PLUS
4803 && REG_P (XEXP (XEXP (retaddr, 0), 0))
4804 && GET_CODE (XEXP (XEXP (retaddr, 0), 1)) == CONST_INT)
4806 base = gen_rtx_REG (Pmode, REGNO (XEXP (XEXP (retaddr, 0), 0)));
4807 offset = INTVAL (XEXP (XEXP (retaddr, 0), 1));
4812 /* If the base of the location containing the return pointer
4813 is SP, we must update it with the replacement address. Otherwise,
4814 just build the necessary MEM. */
4815 retaddr = plus_constant (base, offset);
4816 if (base == stack_pointer_rtx)
4817 retaddr = simplify_replace_rtx (retaddr, stack_pointer_rtx,
4818 plus_constant (info.sp_equiv_reg,
4821 retaddr = gen_rtx_MEM (Pmode, retaddr);
4823 /* If there is a pending load to the equivalent register for SP
4824 and we reference that register, we must load our address into
4825 a scratch register and then do that load. */
4826 if (info.equiv_reg_src
4827 && reg_overlap_mentioned_p (info.equiv_reg_src, retaddr))
4832 for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
4833 if (HARD_REGNO_MODE_OK (regno, Pmode)
4834 && !fixed_regs[regno]
4835 && TEST_HARD_REG_BIT (regs_invalidated_by_call, regno)
4836 && !REGNO_REG_SET_P (EXIT_BLOCK_PTR->global_live_at_start,
4838 && !refers_to_regno_p (regno,
4839 regno + hard_regno_nregs[regno]
4841 info.equiv_reg_src, NULL)
4842 && info.const_equiv[regno] == 0)
4845 if (regno == FIRST_PSEUDO_REGISTER)
4848 reg = gen_rtx_REG (Pmode, regno);
4849 emit_move_insn (reg, retaddr);
4853 emit_equiv_load (&info);
4854 jump_insn = emit_jump_insn (gen_indirect_jump (retaddr));
4856 /* Show the SET in the above insn is a RETURN. */
4857 jump_set = single_set (jump_insn);
4861 SET_IS_RETURN_P (jump_set) = 1;
4864 /* If SP is not mentioned in the pattern and its equivalent register, if
4865 any, is not modified, just emit it. Otherwise, if neither is set,
4866 replace the reference to SP and emit the insn. If none of those are
4867 true, handle each SET individually. */
4868 else if (!reg_mentioned_p (stack_pointer_rtx, PATTERN (insn))
4869 && (info.sp_equiv_reg == stack_pointer_rtx
4870 || !reg_set_p (info.sp_equiv_reg, insn)))
4872 else if (! reg_set_p (stack_pointer_rtx, insn)
4873 && (info.sp_equiv_reg == stack_pointer_rtx
4874 || !reg_set_p (info.sp_equiv_reg, insn)))
4876 if (! validate_replace_rtx (stack_pointer_rtx,
4877 plus_constant (info.sp_equiv_reg,
4884 else if (GET_CODE (PATTERN (insn)) == SET)
4885 handle_epilogue_set (PATTERN (insn), &info);
4886 else if (GET_CODE (PATTERN (insn)) == PARALLEL)
4888 for (j = 0; j < XVECLEN (PATTERN (insn), 0); j++)
4889 if (GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET)
4890 handle_epilogue_set (XVECEXP (PATTERN (insn), 0, j), &info);
4895 info.sp_equiv_reg = info.new_sp_equiv_reg;
4896 info.sp_offset = info.new_sp_offset;
4898 /* Now update any constants this insn sets. */
4899 note_stores (PATTERN (insn), update_epilogue_consts, &info);
4903 insns = get_insns ();
4908 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
4909 structure that contains information about what we've seen so far. We
4910 process this SET by either updating that data or by emitting one or
4914 handle_epilogue_set (rtx set, struct epi_info *p)
4916 /* First handle the case where we are setting SP. Record what it is being
4917 set from. If unknown, abort. */
4918 if (reg_set_p (stack_pointer_rtx, set))
4920 if (SET_DEST (set) != stack_pointer_rtx)
4923 if (GET_CODE (SET_SRC (set)) == PLUS)
4925 p->new_sp_equiv_reg = XEXP (SET_SRC (set), 0);
4926 if (GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT)
4927 p->new_sp_offset = INTVAL (XEXP (SET_SRC (set), 1));
4928 else if (REG_P (XEXP (SET_SRC (set), 1))
4929 && REGNO (XEXP (SET_SRC (set), 1)) < FIRST_PSEUDO_REGISTER
4930 && p->const_equiv[REGNO (XEXP (SET_SRC (set), 1))] != 0)
4932 = INTVAL (p->const_equiv[REGNO (XEXP (SET_SRC (set), 1))]);
4937 p->new_sp_equiv_reg = SET_SRC (set), p->new_sp_offset = 0;
4939 /* If we are adjusting SP, we adjust from the old data. */
4940 if (p->new_sp_equiv_reg == stack_pointer_rtx)
4942 p->new_sp_equiv_reg = p->sp_equiv_reg;
4943 p->new_sp_offset += p->sp_offset;
4946 if (p->new_sp_equiv_reg == 0 || !REG_P (p->new_sp_equiv_reg))
4952 /* Next handle the case where we are setting SP's equivalent register.
4953 If we already have a value to set it to, abort. We could update, but
4954 there seems little point in handling that case. Note that we have
4955 to allow for the case where we are setting the register set in
4956 the previous part of a PARALLEL inside a single insn. But use the
4957 old offset for any updates within this insn. We must allow for the case
4958 where the register is being set in a different (usually wider) mode than
4960 else if (p->new_sp_equiv_reg != 0 && reg_set_p (p->new_sp_equiv_reg, set))
4962 if (p->equiv_reg_src != 0
4963 || !REG_P (p->new_sp_equiv_reg)
4964 || !REG_P (SET_DEST (set))
4965 || GET_MODE_BITSIZE (GET_MODE (SET_DEST (set))) > BITS_PER_WORD
4966 || REGNO (p->new_sp_equiv_reg) != REGNO (SET_DEST (set)))
4970 = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
4971 plus_constant (p->sp_equiv_reg,
4975 /* Otherwise, replace any references to SP in the insn to its new value
4976 and emit the insn. */
4979 SET_SRC (set) = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
4980 plus_constant (p->sp_equiv_reg,
4982 SET_DEST (set) = simplify_replace_rtx (SET_DEST (set), stack_pointer_rtx,
4983 plus_constant (p->sp_equiv_reg,
4989 /* Update the tracking information for registers set to constants. */
4992 update_epilogue_consts (rtx dest, rtx x, void *data)
4994 struct epi_info *p = (struct epi_info *) data;
4997 if (!REG_P (dest) || REGNO (dest) >= FIRST_PSEUDO_REGISTER)
5000 /* If we are either clobbering a register or doing a partial set,
5001 show we don't know the value. */
5002 else if (GET_CODE (x) == CLOBBER || ! rtx_equal_p (dest, SET_DEST (x)))
5003 p->const_equiv[REGNO (dest)] = 0;
5005 /* If we are setting it to a constant, record that constant. */
5006 else if (GET_CODE (SET_SRC (x)) == CONST_INT)
5007 p->const_equiv[REGNO (dest)] = SET_SRC (x);
5009 /* If this is a binary operation between a register we have been tracking
5010 and a constant, see if we can compute a new constant value. */
5011 else if (ARITHMETIC_P (SET_SRC (x))
5012 && REG_P (XEXP (SET_SRC (x), 0))
5013 && REGNO (XEXP (SET_SRC (x), 0)) < FIRST_PSEUDO_REGISTER
5014 && p->const_equiv[REGNO (XEXP (SET_SRC (x), 0))] != 0
5015 && GET_CODE (XEXP (SET_SRC (x), 1)) == CONST_INT
5016 && 0 != (new = simplify_binary_operation
5017 (GET_CODE (SET_SRC (x)), GET_MODE (dest),
5018 p->const_equiv[REGNO (XEXP (SET_SRC (x), 0))],
5019 XEXP (SET_SRC (x), 1)))
5020 && GET_CODE (new) == CONST_INT)
5021 p->const_equiv[REGNO (dest)] = new;
5023 /* Otherwise, we can't do anything with this value. */
5025 p->const_equiv[REGNO (dest)] = 0;
5028 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
5031 emit_equiv_load (struct epi_info *p)
5033 if (p->equiv_reg_src != 0)
5035 rtx dest = p->sp_equiv_reg;
5037 if (GET_MODE (p->equiv_reg_src) != GET_MODE (dest))
5038 dest = gen_rtx_REG (GET_MODE (p->equiv_reg_src),
5039 REGNO (p->sp_equiv_reg));
5041 emit_move_insn (dest, p->equiv_reg_src);
5042 p->equiv_reg_src = 0;
5047 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
5048 this into place with notes indicating where the prologue ends and where
5049 the epilogue begins. Update the basic block information when possible. */
5052 thread_prologue_and_epilogue_insns (rtx f ATTRIBUTE_UNUSED)
5056 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
5059 #ifdef HAVE_prologue
5060 rtx prologue_end = NULL_RTX;
5062 #if defined (HAVE_epilogue) || defined(HAVE_return)
5063 rtx epilogue_end = NULL_RTX;
5066 #ifdef HAVE_prologue
5070 seq = gen_prologue ();
5073 /* Retain a map of the prologue insns. */
5074 record_insns (seq, &prologue);
5075 prologue_end = emit_note (NOTE_INSN_PROLOGUE_END);
5079 set_insn_locators (seq, prologue_locator);
5081 /* Can't deal with multiple successors of the entry block
5082 at the moment. Function should always have at least one
5084 if (!ENTRY_BLOCK_PTR->succ || ENTRY_BLOCK_PTR->succ->succ_next)
5087 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
5092 /* If the exit block has no non-fake predecessors, we don't need
5094 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
5095 if ((e->flags & EDGE_FAKE) == 0)
5101 if (optimize && HAVE_return)
5103 /* If we're allowed to generate a simple return instruction,
5104 then by definition we don't need a full epilogue. Examine
5105 the block that falls through to EXIT. If it does not
5106 contain any code, examine its predecessors and try to
5107 emit (conditional) return instructions. */
5113 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
5114 if (e->flags & EDGE_FALLTHRU)
5120 /* Verify that there are no active instructions in the last block. */
5121 label = BB_END (last);
5122 while (label && GET_CODE (label) != CODE_LABEL)
5124 if (active_insn_p (label))
5126 label = PREV_INSN (label);
5129 if (BB_HEAD (last) == label && GET_CODE (label) == CODE_LABEL)
5131 rtx epilogue_line_note = NULL_RTX;
5133 /* Locate the line number associated with the closing brace,
5134 if we can find one. */
5135 for (seq = get_last_insn ();
5136 seq && ! active_insn_p (seq);
5137 seq = PREV_INSN (seq))
5138 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
5140 epilogue_line_note = seq;
5144 for (e = last->pred; e; e = e_next)
5146 basic_block bb = e->src;
5149 e_next = e->pred_next;
5150 if (bb == ENTRY_BLOCK_PTR)
5154 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
5157 /* If we have an unconditional jump, we can replace that
5158 with a simple return instruction. */
5159 if (simplejump_p (jump))
5161 emit_return_into_block (bb, epilogue_line_note);
5165 /* If we have a conditional jump, we can try to replace
5166 that with a conditional return instruction. */
5167 else if (condjump_p (jump))
5169 if (! redirect_jump (jump, 0, 0))
5172 /* If this block has only one successor, it both jumps
5173 and falls through to the fallthru block, so we can't
5175 if (bb->succ->succ_next == NULL)
5181 /* Fix up the CFG for the successful change we just made. */
5182 redirect_edge_succ (e, EXIT_BLOCK_PTR);
5185 /* Emit a return insn for the exit fallthru block. Whether
5186 this is still reachable will be determined later. */
5188 emit_barrier_after (BB_END (last));
5189 emit_return_into_block (last, epilogue_line_note);
5190 epilogue_end = BB_END (last);
5191 last->succ->flags &= ~EDGE_FALLTHRU;
5196 /* Find the edge that falls through to EXIT. Other edges may exist
5197 due to RETURN instructions, but those don't need epilogues.
5198 There really shouldn't be a mixture -- either all should have
5199 been converted or none, however... */
5201 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
5202 if (e->flags & EDGE_FALLTHRU)
5207 #ifdef HAVE_epilogue
5211 epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG);
5213 seq = gen_epilogue ();
5215 #ifdef INCOMING_RETURN_ADDR_RTX
5216 /* If this function returns with the stack depressed and we can support
5217 it, massage the epilogue to actually do that. */
5218 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
5219 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
5220 seq = keep_stack_depressed (seq);
5223 emit_jump_insn (seq);
5225 /* Retain a map of the epilogue insns. */
5226 record_insns (seq, &epilogue);
5227 set_insn_locators (seq, epilogue_locator);
5232 insert_insn_on_edge (seq, e);
5240 if (! next_active_insn (BB_END (e->src)))
5242 /* We have a fall-through edge to the exit block, the source is not
5243 at the end of the function, and there will be an assembler epilogue
5244 at the end of the function.
5245 We can't use force_nonfallthru here, because that would try to
5246 use return. Inserting a jump 'by hand' is extremely messy, so
5247 we take advantage of cfg_layout_finalize using
5248 fixup_fallthru_exit_predecessor. */
5249 cfg_layout_initialize ();
5250 FOR_EACH_BB (cur_bb)
5251 if (cur_bb->index >= 0 && cur_bb->next_bb->index >= 0)
5252 cur_bb->rbi->next = cur_bb->next_bb;
5253 cfg_layout_finalize ();
5258 commit_edge_insertions ();
5260 #ifdef HAVE_sibcall_epilogue
5261 /* Emit sibling epilogues before any sibling call sites. */
5262 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
5264 basic_block bb = e->src;
5265 rtx insn = BB_END (bb);
5269 if (GET_CODE (insn) != CALL_INSN
5270 || ! SIBLING_CALL_P (insn))
5274 emit_insn (gen_sibcall_epilogue ());
5278 /* Retain a map of the epilogue insns. Used in life analysis to
5279 avoid getting rid of sibcall epilogue insns. Do this before we
5280 actually emit the sequence. */
5281 record_insns (seq, &sibcall_epilogue);
5282 set_insn_locators (seq, epilogue_locator);
5284 i = PREV_INSN (insn);
5285 newinsn = emit_insn_before (seq, insn);
5289 #ifdef HAVE_prologue
5290 /* This is probably all useless now that we use locators. */
5295 /* GDB handles `break f' by setting a breakpoint on the first
5296 line note after the prologue. Which means (1) that if
5297 there are line number notes before where we inserted the
5298 prologue we should move them, and (2) we should generate a
5299 note before the end of the first basic block, if there isn't
5302 ??? This behavior is completely broken when dealing with
5303 multiple entry functions. We simply place the note always
5304 into first basic block and let alternate entry points
5308 for (insn = prologue_end; insn; insn = prev)
5310 prev = PREV_INSN (insn);
5311 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
5313 /* Note that we cannot reorder the first insn in the
5314 chain, since rest_of_compilation relies on that
5315 remaining constant. */
5318 reorder_insns (insn, insn, prologue_end);
5322 /* Find the last line number note in the first block. */
5323 for (insn = BB_END (ENTRY_BLOCK_PTR->next_bb);
5324 insn != prologue_end && insn;
5325 insn = PREV_INSN (insn))
5326 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
5329 /* If we didn't find one, make a copy of the first line number
5333 for (insn = next_active_insn (prologue_end);
5335 insn = PREV_INSN (insn))
5336 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
5338 emit_note_copy_after (insn, prologue_end);
5344 #ifdef HAVE_epilogue
5349 /* Similarly, move any line notes that appear after the epilogue.
5350 There is no need, however, to be quite so anal about the existence
5351 of such a note. Also move the NOTE_INSN_FUNCTION_END and (possibly)
5352 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
5354 for (insn = epilogue_end; insn; insn = next)
5356 next = NEXT_INSN (insn);
5357 if (GET_CODE (insn) == NOTE
5358 && (NOTE_LINE_NUMBER (insn) > 0
5359 || NOTE_LINE_NUMBER (insn) == NOTE_INSN_FUNCTION_BEG
5360 || NOTE_LINE_NUMBER (insn) == NOTE_INSN_FUNCTION_END))
5361 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
5367 /* Reposition the prologue-end and epilogue-begin notes after instruction
5368 scheduling and delayed branch scheduling. */
5371 reposition_prologue_and_epilogue_notes (rtx f ATTRIBUTE_UNUSED)
5373 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
5374 rtx insn, last, note;
5377 if ((len = VARRAY_SIZE (prologue)) > 0)
5381 /* Scan from the beginning until we reach the last prologue insn.
5382 We apparently can't depend on basic_block_{head,end} after
5384 for (insn = f; insn; insn = NEXT_INSN (insn))
5386 if (GET_CODE (insn) == NOTE)
5388 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
5391 else if (contains (insn, prologue))
5401 /* Find the prologue-end note if we haven't already, and
5402 move it to just after the last prologue insn. */
5405 for (note = last; (note = NEXT_INSN (note));)
5406 if (GET_CODE (note) == NOTE
5407 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
5411 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
5412 if (GET_CODE (last) == CODE_LABEL)
5413 last = NEXT_INSN (last);
5414 reorder_insns (note, note, last);
5418 if ((len = VARRAY_SIZE (epilogue)) > 0)
5422 /* Scan from the end until we reach the first epilogue insn.
5423 We apparently can't depend on basic_block_{head,end} after
5425 for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
5427 if (GET_CODE (insn) == NOTE)
5429 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
5432 else if (contains (insn, epilogue))
5442 /* Find the epilogue-begin note if we haven't already, and
5443 move it to just before the first epilogue insn. */
5446 for (note = insn; (note = PREV_INSN (note));)
5447 if (GET_CODE (note) == NOTE
5448 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
5452 if (PREV_INSN (last) != note)
5453 reorder_insns (note, note, PREV_INSN (last));
5456 #endif /* HAVE_prologue or HAVE_epilogue */
5459 /* Called once, at initialization, to initialize function.c. */
5462 init_function_once (void)
5464 VARRAY_INT_INIT (prologue, 0, "prologue");
5465 VARRAY_INT_INIT (epilogue, 0, "epilogue");
5466 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");
5469 /* Resets insn_block_boundaries array. */
5472 reset_block_changes (void)
5474 VARRAY_TREE_INIT (cfun->ib_boundaries_block, 100, "ib_boundaries_block");
5475 VARRAY_PUSH_TREE (cfun->ib_boundaries_block, NULL_TREE);
5478 /* Record the boundary for BLOCK. */
5480 record_block_change (tree block)
5488 last_block = VARRAY_TOP_TREE (cfun->ib_boundaries_block);
5489 VARRAY_POP (cfun->ib_boundaries_block);
5491 for (i = VARRAY_ACTIVE_SIZE (cfun->ib_boundaries_block); i < n; i++)
5492 VARRAY_PUSH_TREE (cfun->ib_boundaries_block, last_block);
5494 VARRAY_PUSH_TREE (cfun->ib_boundaries_block, block);
5497 /* Finishes record of boundaries. */
5498 void finalize_block_changes (void)
5500 record_block_change (DECL_INITIAL (current_function_decl));
5503 /* For INSN return the BLOCK it belongs to. */
5505 check_block_change (rtx insn, tree *block)
5507 unsigned uid = INSN_UID (insn);
5509 if (uid >= VARRAY_ACTIVE_SIZE (cfun->ib_boundaries_block))
5512 *block = VARRAY_TREE (cfun->ib_boundaries_block, uid);
5515 /* Releases the ib_boundaries_block records. */
5517 free_block_changes (void)
5519 cfun->ib_boundaries_block = NULL;
5522 /* Returns the name of the current function. */
5524 current_function_name (void)
5526 return lang_hooks.decl_printable_name (cfun->decl, 2);
5529 #include "gt-function.h"