1 /* Expands front end tree to back end RTL for GCC.
2 Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005
4 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 2, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING. If not, write to the Free
20 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
23 /* This file handles the generation of rtl code from tree structure
24 at the level of the function as a whole.
25 It creates the rtl expressions for parameters and auto variables
26 and has full responsibility for allocating stack slots.
28 `expand_function_start' is called at the beginning of a function,
29 before the function body is parsed, and `expand_function_end' is
30 called after parsing the body.
32 Call `assign_stack_local' to allocate a stack slot for a local variable.
33 This is usually done during the RTL generation for the function body,
34 but it can also be done in the reload pass when a pseudo-register does
35 not get a hard register. */
39 #include "coretypes.h"
50 #include "hard-reg-set.h"
51 #include "insn-config.h"
54 #include "basic-block.h"
59 #include "integrate.h"
60 #include "langhooks.h"
62 #include "cfglayout.h"
63 #include "tree-gimple.h"
65 #ifndef LOCAL_ALIGNMENT
66 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
69 #ifndef STACK_ALIGNMENT_NEEDED
70 #define STACK_ALIGNMENT_NEEDED 1
73 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
75 /* Some systems use __main in a way incompatible with its use in gcc, in these
76 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
77 give the same symbol without quotes for an alternative entry point. You
78 must define both, or neither. */
80 #define NAME__MAIN "__main"
83 /* Round a value to the lowest integer less than it that is a multiple of
84 the required alignment. Avoid using division in case the value is
85 negative. Assume the alignment is a power of two. */
86 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
88 /* Similar, but round to the next highest integer that meets the
90 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
92 /* Nonzero if function being compiled doesn't contain any calls
93 (ignoring the prologue and epilogue). This is set prior to
94 local register allocation and is valid for the remaining
96 int current_function_is_leaf;
98 /* Nonzero if function being compiled doesn't modify the stack pointer
99 (ignoring the prologue and epilogue). This is only valid after
100 life_analysis has run. */
101 int current_function_sp_is_unchanging;
103 /* Nonzero if the function being compiled is a leaf function which only
104 uses leaf registers. This is valid after reload (specifically after
105 sched2) and is useful only if the port defines LEAF_REGISTERS. */
106 int current_function_uses_only_leaf_regs;
108 /* Nonzero once virtual register instantiation has been done.
109 assign_stack_local uses frame_pointer_rtx when this is nonzero.
110 calls.c:emit_library_call_value_1 uses it to set up
111 post-instantiation libcalls. */
112 int virtuals_instantiated;
114 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
115 static GTY(()) int funcdef_no;
117 /* These variables hold pointers to functions to create and destroy
118 target specific, per-function data structures. */
119 struct machine_function * (*init_machine_status) (void);
121 /* The currently compiled function. */
122 struct function *cfun = 0;
124 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
125 static GTY(()) varray_type prologue;
126 static GTY(()) varray_type epilogue;
128 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
130 static GTY(()) varray_type sibcall_epilogue;
132 /* In order to evaluate some expressions, such as function calls returning
133 structures in memory, we need to temporarily allocate stack locations.
134 We record each allocated temporary in the following structure.
136 Associated with each temporary slot is a nesting level. When we pop up
137 one level, all temporaries associated with the previous level are freed.
138 Normally, all temporaries are freed after the execution of the statement
139 in which they were created. However, if we are inside a ({...}) grouping,
140 the result may be in a temporary and hence must be preserved. If the
141 result could be in a temporary, we preserve it if we can determine which
142 one it is in. If we cannot determine which temporary may contain the
143 result, all temporaries are preserved. A temporary is preserved by
144 pretending it was allocated at the previous nesting level.
146 Automatic variables are also assigned temporary slots, at the nesting
147 level where they are defined. They are marked a "kept" so that
148 free_temp_slots will not free them. */
150 struct temp_slot GTY(())
152 /* Points to next temporary slot. */
153 struct temp_slot *next;
154 /* Points to previous temporary slot. */
155 struct temp_slot *prev;
157 /* The rtx to used to reference the slot. */
159 /* The rtx used to represent the address if not the address of the
160 slot above. May be an EXPR_LIST if multiple addresses exist. */
162 /* The alignment (in bits) of the slot. */
164 /* The size, in units, of the slot. */
166 /* The type of the object in the slot, or zero if it doesn't correspond
167 to a type. We use this to determine whether a slot can be reused.
168 It can be reused if objects of the type of the new slot will always
169 conflict with objects of the type of the old slot. */
171 /* Nonzero if this temporary is currently in use. */
173 /* Nonzero if this temporary has its address taken. */
175 /* Nesting level at which this slot is being used. */
177 /* Nonzero if this should survive a call to free_temp_slots. */
179 /* The offset of the slot from the frame_pointer, including extra space
180 for alignment. This info is for combine_temp_slots. */
181 HOST_WIDE_INT base_offset;
182 /* The size of the slot, including extra space for alignment. This
183 info is for combine_temp_slots. */
184 HOST_WIDE_INT full_size;
187 /* Forward declarations. */
189 static rtx assign_stack_local_1 (enum machine_mode, HOST_WIDE_INT, int,
191 static struct temp_slot *find_temp_slot_from_address (rtx);
192 static void pad_to_arg_alignment (struct args_size *, int, struct args_size *);
193 static void pad_below (struct args_size *, enum machine_mode, tree);
194 static void reorder_blocks_1 (rtx, tree, VEC(tree,heap) **);
195 static void reorder_fix_fragments (tree);
196 static int all_blocks (tree, tree *);
197 static tree *get_block_vector (tree, int *);
198 extern tree debug_find_var_in_block_tree (tree, tree);
199 /* We always define `record_insns' even if it's not used so that we
200 can always export `prologue_epilogue_contains'. */
201 static void record_insns (rtx, varray_type *) ATTRIBUTE_UNUSED;
202 static int contains (rtx, varray_type);
204 static void emit_return_into_block (basic_block, rtx);
206 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
207 static rtx keep_stack_depressed (rtx);
209 static void prepare_function_start (tree);
210 static void do_clobber_return_reg (rtx, void *);
211 static void do_use_return_reg (rtx, void *);
212 static void set_insn_locators (rtx, int) ATTRIBUTE_UNUSED;
214 /* Pointer to chain of `struct function' for containing functions. */
215 struct function *outer_function_chain;
217 /* Given a function decl for a containing function,
218 return the `struct function' for it. */
221 find_function_data (tree decl)
225 for (p = outer_function_chain; p; p = p->outer)
232 /* Save the current context for compilation of a nested function.
233 This is called from language-specific code. The caller should use
234 the enter_nested langhook to save any language-specific state,
235 since this function knows only about language-independent
239 push_function_context_to (tree context ATTRIBUTE_UNUSED)
244 init_dummy_function_start ();
247 p->outer = outer_function_chain;
248 outer_function_chain = p;
250 lang_hooks.function.enter_nested (p);
256 push_function_context (void)
258 push_function_context_to (current_function_decl);
261 /* Restore the last saved context, at the end of a nested function.
262 This function is called from language-specific code. */
265 pop_function_context_from (tree context ATTRIBUTE_UNUSED)
267 struct function *p = outer_function_chain;
270 outer_function_chain = p->outer;
272 current_function_decl = p->decl;
274 lang_hooks.function.leave_nested (p);
276 /* Reset variables that have known state during rtx generation. */
277 virtuals_instantiated = 0;
278 generating_concat_p = 1;
282 pop_function_context (void)
284 pop_function_context_from (current_function_decl);
287 /* Clear out all parts of the state in F that can safely be discarded
288 after the function has been parsed, but not compiled, to let
289 garbage collection reclaim the memory. */
292 free_after_parsing (struct function *f)
294 /* f->expr->forced_labels is used by code generation. */
295 /* f->emit->regno_reg_rtx is used by code generation. */
296 /* f->varasm is used by code generation. */
297 /* f->eh->eh_return_stub_label is used by code generation. */
299 lang_hooks.function.final (f);
302 /* Clear out all parts of the state in F that can safely be discarded
303 after the function has been compiled, to let garbage collection
304 reclaim the memory. */
307 free_after_compilation (struct function *f)
316 f->x_avail_temp_slots = NULL;
317 f->x_used_temp_slots = NULL;
318 f->arg_offset_rtx = NULL;
319 f->return_rtx = NULL;
320 f->internal_arg_pointer = NULL;
321 f->x_nonlocal_goto_handler_labels = NULL;
322 f->x_return_label = NULL;
323 f->x_naked_return_label = NULL;
324 f->x_stack_slot_list = NULL;
325 f->x_tail_recursion_reentry = NULL;
326 f->x_arg_pointer_save_area = NULL;
327 f->x_parm_birth_insn = NULL;
328 f->original_arg_vector = NULL;
329 f->original_decl_initial = NULL;
330 f->epilogue_delay_list = NULL;
333 /* Allocate fixed slots in the stack frame of the current function. */
335 /* Return size needed for stack frame based on slots so far allocated in
337 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
338 the caller may have to do that. */
341 get_func_frame_size (struct function *f)
343 #ifdef FRAME_GROWS_DOWNWARD
344 return -f->x_frame_offset;
346 return f->x_frame_offset;
350 /* Return size needed for stack frame based on slots so far allocated.
351 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
352 the caller may have to do that. */
354 get_frame_size (void)
356 return get_func_frame_size (cfun);
359 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
360 with machine mode MODE.
362 ALIGN controls the amount of alignment for the address of the slot:
363 0 means according to MODE,
364 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
365 -2 means use BITS_PER_UNIT,
366 positive specifies alignment boundary in bits.
368 We do not round to stack_boundary here.
370 FUNCTION specifies the function to allocate in. */
373 assign_stack_local_1 (enum machine_mode mode, HOST_WIDE_INT size, int align,
374 struct function *function)
377 int bigend_correction = 0;
378 unsigned int alignment;
379 int frame_off, frame_alignment, frame_phase;
386 alignment = BIGGEST_ALIGNMENT;
388 alignment = GET_MODE_ALIGNMENT (mode);
390 /* Allow the target to (possibly) increase the alignment of this
392 type = lang_hooks.types.type_for_mode (mode, 0);
394 alignment = LOCAL_ALIGNMENT (type, alignment);
396 alignment /= BITS_PER_UNIT;
398 else if (align == -1)
400 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
401 size = CEIL_ROUND (size, alignment);
403 else if (align == -2)
404 alignment = 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
406 alignment = align / BITS_PER_UNIT;
408 #ifdef FRAME_GROWS_DOWNWARD
409 function->x_frame_offset -= size;
412 /* Ignore alignment we can't do with expected alignment of the boundary. */
413 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
414 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
416 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
417 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
419 /* Calculate how many bytes the start of local variables is off from
421 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
422 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
423 frame_phase = frame_off ? frame_alignment - frame_off : 0;
425 /* Round the frame offset to the specified alignment. The default is
426 to always honor requests to align the stack but a port may choose to
427 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
428 if (STACK_ALIGNMENT_NEEDED
432 /* We must be careful here, since FRAME_OFFSET might be negative and
433 division with a negative dividend isn't as well defined as we might
434 like. So we instead assume that ALIGNMENT is a power of two and
435 use logical operations which are unambiguous. */
436 #ifdef FRAME_GROWS_DOWNWARD
437 function->x_frame_offset
438 = (FLOOR_ROUND (function->x_frame_offset - frame_phase,
439 (unsigned HOST_WIDE_INT) alignment)
442 function->x_frame_offset
443 = (CEIL_ROUND (function->x_frame_offset - frame_phase,
444 (unsigned HOST_WIDE_INT) alignment)
449 /* On a big-endian machine, if we are allocating more space than we will use,
450 use the least significant bytes of those that are allocated. */
451 if (BYTES_BIG_ENDIAN && mode != BLKmode)
452 bigend_correction = size - GET_MODE_SIZE (mode);
454 /* If we have already instantiated virtual registers, return the actual
455 address relative to the frame pointer. */
456 if (function == cfun && virtuals_instantiated)
457 addr = plus_constant (frame_pointer_rtx,
459 (frame_offset + bigend_correction
460 + STARTING_FRAME_OFFSET, Pmode));
462 addr = plus_constant (virtual_stack_vars_rtx,
464 (function->x_frame_offset + bigend_correction,
467 #ifndef FRAME_GROWS_DOWNWARD
468 function->x_frame_offset += size;
471 x = gen_rtx_MEM (mode, addr);
473 function->x_stack_slot_list
474 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
479 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
483 assign_stack_local (enum machine_mode mode, HOST_WIDE_INT size, int align)
485 return assign_stack_local_1 (mode, size, align, cfun);
489 /* Removes temporary slot TEMP from LIST. */
492 cut_slot_from_list (struct temp_slot *temp, struct temp_slot **list)
495 temp->next->prev = temp->prev;
497 temp->prev->next = temp->next;
501 temp->prev = temp->next = NULL;
504 /* Inserts temporary slot TEMP to LIST. */
507 insert_slot_to_list (struct temp_slot *temp, struct temp_slot **list)
511 (*list)->prev = temp;
516 /* Returns the list of used temp slots at LEVEL. */
518 static struct temp_slot **
519 temp_slots_at_level (int level)
522 if (!used_temp_slots)
523 VARRAY_GENERIC_PTR_INIT (used_temp_slots, 3, "used_temp_slots");
525 while (level >= (int) VARRAY_ACTIVE_SIZE (used_temp_slots))
526 VARRAY_PUSH_GENERIC_PTR (used_temp_slots, NULL);
528 return (struct temp_slot **) &VARRAY_GENERIC_PTR (used_temp_slots, level);
531 /* Returns the maximal temporary slot level. */
534 max_slot_level (void)
536 if (!used_temp_slots)
539 return VARRAY_ACTIVE_SIZE (used_temp_slots) - 1;
542 /* Moves temporary slot TEMP to LEVEL. */
545 move_slot_to_level (struct temp_slot *temp, int level)
547 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
548 insert_slot_to_list (temp, temp_slots_at_level (level));
552 /* Make temporary slot TEMP available. */
555 make_slot_available (struct temp_slot *temp)
557 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
558 insert_slot_to_list (temp, &avail_temp_slots);
563 /* Allocate a temporary stack slot and record it for possible later
566 MODE is the machine mode to be given to the returned rtx.
568 SIZE is the size in units of the space required. We do no rounding here
569 since assign_stack_local will do any required rounding.
571 KEEP is 1 if this slot is to be retained after a call to
572 free_temp_slots. Automatic variables for a block are allocated
573 with this flag. KEEP values of 2 or 3 were needed respectively
574 for variables whose lifetime is controlled by CLEANUP_POINT_EXPRs
575 or for SAVE_EXPRs, but they are now unused.
577 TYPE is the type that will be used for the stack slot. */
580 assign_stack_temp_for_type (enum machine_mode mode, HOST_WIDE_INT size,
584 struct temp_slot *p, *best_p = 0, *selected = NULL, **pp;
587 /* If SIZE is -1 it means that somebody tried to allocate a temporary
588 of a variable size. */
589 gcc_assert (size != -1);
591 /* These are now unused. */
592 gcc_assert (keep <= 1);
595 align = BIGGEST_ALIGNMENT;
597 align = GET_MODE_ALIGNMENT (mode);
600 type = lang_hooks.types.type_for_mode (mode, 0);
603 align = LOCAL_ALIGNMENT (type, align);
605 /* Try to find an available, already-allocated temporary of the proper
606 mode which meets the size and alignment requirements. Choose the
607 smallest one with the closest alignment. */
608 for (p = avail_temp_slots; p; p = p->next)
610 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
611 && objects_must_conflict_p (p->type, type)
612 && (best_p == 0 || best_p->size > p->size
613 || (best_p->size == p->size && best_p->align > p->align)))
615 if (p->align == align && p->size == size)
618 cut_slot_from_list (selected, &avail_temp_slots);
626 /* Make our best, if any, the one to use. */
630 cut_slot_from_list (selected, &avail_temp_slots);
632 /* If there are enough aligned bytes left over, make them into a new
633 temp_slot so that the extra bytes don't get wasted. Do this only
634 for BLKmode slots, so that we can be sure of the alignment. */
635 if (GET_MODE (best_p->slot) == BLKmode)
637 int alignment = best_p->align / BITS_PER_UNIT;
638 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
640 if (best_p->size - rounded_size >= alignment)
642 p = ggc_alloc (sizeof (struct temp_slot));
643 p->in_use = p->addr_taken = 0;
644 p->size = best_p->size - rounded_size;
645 p->base_offset = best_p->base_offset + rounded_size;
646 p->full_size = best_p->full_size - rounded_size;
647 p->slot = gen_rtx_MEM (BLKmode,
648 plus_constant (XEXP (best_p->slot, 0),
650 p->align = best_p->align;
652 p->type = best_p->type;
653 insert_slot_to_list (p, &avail_temp_slots);
655 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
658 best_p->size = rounded_size;
659 best_p->full_size = rounded_size;
664 /* If we still didn't find one, make a new temporary. */
667 HOST_WIDE_INT frame_offset_old = frame_offset;
669 p = ggc_alloc (sizeof (struct temp_slot));
671 /* We are passing an explicit alignment request to assign_stack_local.
672 One side effect of that is assign_stack_local will not round SIZE
673 to ensure the frame offset remains suitably aligned.
675 So for requests which depended on the rounding of SIZE, we go ahead
676 and round it now. We also make sure ALIGNMENT is at least
677 BIGGEST_ALIGNMENT. */
678 gcc_assert (mode != BLKmode || align == BIGGEST_ALIGNMENT);
679 p->slot = assign_stack_local (mode,
681 ? CEIL_ROUND (size, (int) align / BITS_PER_UNIT)
687 /* The following slot size computation is necessary because we don't
688 know the actual size of the temporary slot until assign_stack_local
689 has performed all the frame alignment and size rounding for the
690 requested temporary. Note that extra space added for alignment
691 can be either above or below this stack slot depending on which
692 way the frame grows. We include the extra space if and only if it
693 is above this slot. */
694 #ifdef FRAME_GROWS_DOWNWARD
695 p->size = frame_offset_old - frame_offset;
700 /* Now define the fields used by combine_temp_slots. */
701 #ifdef FRAME_GROWS_DOWNWARD
702 p->base_offset = frame_offset;
703 p->full_size = frame_offset_old - frame_offset;
705 p->base_offset = frame_offset_old;
706 p->full_size = frame_offset - frame_offset_old;
717 p->level = temp_slot_level;
720 pp = temp_slots_at_level (p->level);
721 insert_slot_to_list (p, pp);
723 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
724 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
725 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list);
727 /* If we know the alias set for the memory that will be used, use
728 it. If there's no TYPE, then we don't know anything about the
729 alias set for the memory. */
730 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
731 set_mem_align (slot, align);
733 /* If a type is specified, set the relevant flags. */
736 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
737 MEM_SET_IN_STRUCT_P (slot, AGGREGATE_TYPE_P (type));
743 /* Allocate a temporary stack slot and record it for possible later
744 reuse. First three arguments are same as in preceding function. */
747 assign_stack_temp (enum machine_mode mode, HOST_WIDE_INT size, int keep)
749 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
752 /* Assign a temporary.
753 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
754 and so that should be used in error messages. In either case, we
755 allocate of the given type.
756 KEEP is as for assign_stack_temp.
757 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
758 it is 0 if a register is OK.
759 DONT_PROMOTE is 1 if we should not promote values in register
763 assign_temp (tree type_or_decl, int keep, int memory_required,
764 int dont_promote ATTRIBUTE_UNUSED)
767 enum machine_mode mode;
772 if (DECL_P (type_or_decl))
773 decl = type_or_decl, type = TREE_TYPE (decl);
775 decl = NULL, type = type_or_decl;
777 mode = TYPE_MODE (type);
779 unsignedp = TYPE_UNSIGNED (type);
782 if (mode == BLKmode || memory_required)
784 HOST_WIDE_INT size = int_size_in_bytes (type);
788 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
789 problems with allocating the stack space. */
793 /* Unfortunately, we don't yet know how to allocate variable-sized
794 temporaries. However, sometimes we have a fixed upper limit on
795 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
796 instead. This is the case for Chill variable-sized strings. */
797 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
798 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
799 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
800 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
802 /* If we still haven't been able to get a size, see if the language
803 can compute a maximum size. */
805 && (size_tree = lang_hooks.types.max_size (type)) != 0
806 && host_integerp (size_tree, 1))
807 size = tree_low_cst (size_tree, 1);
809 /* The size of the temporary may be too large to fit into an integer. */
810 /* ??? Not sure this should happen except for user silliness, so limit
811 this to things that aren't compiler-generated temporaries. The
812 rest of the time we'll die in assign_stack_temp_for_type. */
813 if (decl && size == -1
814 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
816 error ("%Jsize of variable %qD is too large", decl, decl);
820 tmp = assign_stack_temp_for_type (mode, size, keep, type);
826 mode = promote_mode (type, mode, &unsignedp, 0);
829 return gen_reg_rtx (mode);
832 /* Combine temporary stack slots which are adjacent on the stack.
834 This allows for better use of already allocated stack space. This is only
835 done for BLKmode slots because we can be sure that we won't have alignment
836 problems in this case. */
839 combine_temp_slots (void)
841 struct temp_slot *p, *q, *next, *next_q;
844 /* We can't combine slots, because the information about which slot
845 is in which alias set will be lost. */
846 if (flag_strict_aliasing)
849 /* If there are a lot of temp slots, don't do anything unless
850 high levels of optimization. */
851 if (! flag_expensive_optimizations)
852 for (p = avail_temp_slots, num_slots = 0; p; p = p->next, num_slots++)
853 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
856 for (p = avail_temp_slots; p; p = next)
862 if (GET_MODE (p->slot) != BLKmode)
865 for (q = p->next; q; q = next_q)
871 if (GET_MODE (q->slot) != BLKmode)
874 if (p->base_offset + p->full_size == q->base_offset)
876 /* Q comes after P; combine Q into P. */
878 p->full_size += q->full_size;
881 else if (q->base_offset + q->full_size == p->base_offset)
883 /* P comes after Q; combine P into Q. */
885 q->full_size += p->full_size;
890 cut_slot_from_list (q, &avail_temp_slots);
893 /* Either delete P or advance past it. */
895 cut_slot_from_list (p, &avail_temp_slots);
899 /* Find the temp slot corresponding to the object at address X. */
901 static struct temp_slot *
902 find_temp_slot_from_address (rtx x)
908 for (i = max_slot_level (); i >= 0; i--)
909 for (p = *temp_slots_at_level (i); p; p = p->next)
911 if (XEXP (p->slot, 0) == x
913 || (GET_CODE (x) == PLUS
914 && XEXP (x, 0) == virtual_stack_vars_rtx
915 && GET_CODE (XEXP (x, 1)) == CONST_INT
916 && INTVAL (XEXP (x, 1)) >= p->base_offset
917 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
920 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
921 for (next = p->address; next; next = XEXP (next, 1))
922 if (XEXP (next, 0) == x)
926 /* If we have a sum involving a register, see if it points to a temp
928 if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 0))
929 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
931 else if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 1))
932 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
938 /* Indicate that NEW is an alternate way of referring to the temp slot
939 that previously was known by OLD. */
942 update_temp_slot_address (rtx old, rtx new)
946 if (rtx_equal_p (old, new))
949 p = find_temp_slot_from_address (old);
951 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
952 is a register, see if one operand of the PLUS is a temporary
953 location. If so, NEW points into it. Otherwise, if both OLD and
954 NEW are a PLUS and if there is a register in common between them.
955 If so, try a recursive call on those values. */
958 if (GET_CODE (old) != PLUS)
963 update_temp_slot_address (XEXP (old, 0), new);
964 update_temp_slot_address (XEXP (old, 1), new);
967 else if (GET_CODE (new) != PLUS)
970 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
971 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
972 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
973 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
974 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
975 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
976 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
977 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
982 /* Otherwise add an alias for the temp's address. */
983 else if (p->address == 0)
987 if (GET_CODE (p->address) != EXPR_LIST)
988 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
990 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
994 /* If X could be a reference to a temporary slot, mark the fact that its
995 address was taken. */
998 mark_temp_addr_taken (rtx x)
1000 struct temp_slot *p;
1005 /* If X is not in memory or is at a constant address, it cannot be in
1006 a temporary slot. */
1007 if (!MEM_P (x) || CONSTANT_P (XEXP (x, 0)))
1010 p = find_temp_slot_from_address (XEXP (x, 0));
1015 /* If X could be a reference to a temporary slot, mark that slot as
1016 belonging to the to one level higher than the current level. If X
1017 matched one of our slots, just mark that one. Otherwise, we can't
1018 easily predict which it is, so upgrade all of them. Kept slots
1019 need not be touched.
1021 This is called when an ({...}) construct occurs and a statement
1022 returns a value in memory. */
1025 preserve_temp_slots (rtx x)
1027 struct temp_slot *p = 0, *next;
1029 /* If there is no result, we still might have some objects whose address
1030 were taken, so we need to make sure they stay around. */
1033 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1038 move_slot_to_level (p, temp_slot_level - 1);
1044 /* If X is a register that is being used as a pointer, see if we have
1045 a temporary slot we know it points to. To be consistent with
1046 the code below, we really should preserve all non-kept slots
1047 if we can't find a match, but that seems to be much too costly. */
1048 if (REG_P (x) && REG_POINTER (x))
1049 p = find_temp_slot_from_address (x);
1051 /* If X is not in memory or is at a constant address, it cannot be in
1052 a temporary slot, but it can contain something whose address was
1054 if (p == 0 && (!MEM_P (x) || CONSTANT_P (XEXP (x, 0))))
1056 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1061 move_slot_to_level (p, temp_slot_level - 1);
1067 /* First see if we can find a match. */
1069 p = find_temp_slot_from_address (XEXP (x, 0));
1073 /* Move everything at our level whose address was taken to our new
1074 level in case we used its address. */
1075 struct temp_slot *q;
1077 if (p->level == temp_slot_level)
1079 for (q = *temp_slots_at_level (temp_slot_level); q; q = next)
1083 if (p != q && q->addr_taken)
1084 move_slot_to_level (q, temp_slot_level - 1);
1087 move_slot_to_level (p, temp_slot_level - 1);
1093 /* Otherwise, preserve all non-kept slots at this level. */
1094 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1099 move_slot_to_level (p, temp_slot_level - 1);
1103 /* Free all temporaries used so far. This is normally called at the
1104 end of generating code for a statement. */
1107 free_temp_slots (void)
1109 struct temp_slot *p, *next;
1111 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1116 make_slot_available (p);
1119 combine_temp_slots ();
1122 /* Push deeper into the nesting level for stack temporaries. */
1125 push_temp_slots (void)
1130 /* Pop a temporary nesting level. All slots in use in the current level
1134 pop_temp_slots (void)
1136 struct temp_slot *p, *next;
1138 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1141 make_slot_available (p);
1144 combine_temp_slots ();
1149 /* Initialize temporary slots. */
1152 init_temp_slots (void)
1154 /* We have not allocated any temporaries yet. */
1155 avail_temp_slots = 0;
1156 used_temp_slots = 0;
1157 temp_slot_level = 0;
1160 /* These routines are responsible for converting virtual register references
1161 to the actual hard register references once RTL generation is complete.
1163 The following four variables are used for communication between the
1164 routines. They contain the offsets of the virtual registers from their
1165 respective hard registers. */
1167 static int in_arg_offset;
1168 static int var_offset;
1169 static int dynamic_offset;
1170 static int out_arg_offset;
1171 static int cfa_offset;
1173 /* In most machines, the stack pointer register is equivalent to the bottom
1176 #ifndef STACK_POINTER_OFFSET
1177 #define STACK_POINTER_OFFSET 0
1180 /* If not defined, pick an appropriate default for the offset of dynamically
1181 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1182 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1184 #ifndef STACK_DYNAMIC_OFFSET
1186 /* The bottom of the stack points to the actual arguments. If
1187 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1188 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1189 stack space for register parameters is not pushed by the caller, but
1190 rather part of the fixed stack areas and hence not included in
1191 `current_function_outgoing_args_size'. Nevertheless, we must allow
1192 for it when allocating stack dynamic objects. */
1194 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
1195 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1196 ((ACCUMULATE_OUTGOING_ARGS \
1197 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
1198 + (STACK_POINTER_OFFSET)) \
1201 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1202 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
1203 + (STACK_POINTER_OFFSET))
1207 /* On most machines, the CFA coincides with the first incoming parm. */
1209 #ifndef ARG_POINTER_CFA_OFFSET
1210 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
1214 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1215 is a virtual register, return the equivalent hard register and set the
1216 offset indirectly through the pointer. Otherwise, return 0. */
1219 instantiate_new_reg (rtx x, HOST_WIDE_INT *poffset)
1222 HOST_WIDE_INT offset;
1224 if (x == virtual_incoming_args_rtx)
1225 new = arg_pointer_rtx, offset = in_arg_offset;
1226 else if (x == virtual_stack_vars_rtx)
1227 new = frame_pointer_rtx, offset = var_offset;
1228 else if (x == virtual_stack_dynamic_rtx)
1229 new = stack_pointer_rtx, offset = dynamic_offset;
1230 else if (x == virtual_outgoing_args_rtx)
1231 new = stack_pointer_rtx, offset = out_arg_offset;
1232 else if (x == virtual_cfa_rtx)
1233 new = arg_pointer_rtx, offset = cfa_offset;
1241 /* A subroutine of instantiate_virtual_regs, called via for_each_rtx.
1242 Instantiate any virtual registers present inside of *LOC. The expression
1243 is simplified, as much as possible, but is not to be considered "valid"
1244 in any sense implied by the target. If any change is made, set CHANGED
1248 instantiate_virtual_regs_in_rtx (rtx *loc, void *data)
1250 HOST_WIDE_INT offset;
1251 bool *changed = (bool *) data;
1258 switch (GET_CODE (x))
1261 new = instantiate_new_reg (x, &offset);
1264 *loc = plus_constant (new, offset);
1271 new = instantiate_new_reg (XEXP (x, 0), &offset);
1274 new = plus_constant (new, offset);
1275 *loc = simplify_gen_binary (PLUS, GET_MODE (x), new, XEXP (x, 1));
1281 /* FIXME -- from old code */
1282 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1283 we can commute the PLUS and SUBREG because pointers into the
1284 frame are well-behaved. */
1294 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1295 matches the predicate for insn CODE operand OPERAND. */
1298 safe_insn_predicate (int code, int operand, rtx x)
1300 const struct insn_operand_data *op_data;
1305 op_data = &insn_data[code].operand[operand];
1306 if (op_data->predicate == NULL)
1309 return op_data->predicate (x, op_data->mode);
1312 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1313 registers present inside of insn. The result will be a valid insn. */
1316 instantiate_virtual_regs_in_insn (rtx insn)
1318 HOST_WIDE_INT offset;
1321 rtx set, new, x, seq;
1323 /* There are some special cases to be handled first. */
1324 set = single_set (insn);
1327 /* We're allowed to assign to a virtual register. This is interpreted
1328 to mean that the underlying register gets assigned the inverse
1329 transformation. This is used, for example, in the handling of
1331 new = instantiate_new_reg (SET_DEST (set), &offset);
1336 for_each_rtx (&SET_SRC (set), instantiate_virtual_regs_in_rtx, NULL);
1337 x = simplify_gen_binary (PLUS, GET_MODE (new), SET_SRC (set),
1339 x = force_operand (x, new);
1341 emit_move_insn (new, x);
1346 emit_insn_before (seq, insn);
1351 /* Handle a straight copy from a virtual register by generating a
1352 new add insn. The difference between this and falling through
1353 to the generic case is avoiding a new pseudo and eliminating a
1354 move insn in the initial rtl stream. */
1355 new = instantiate_new_reg (SET_SRC (set), &offset);
1356 if (new && offset != 0
1357 && REG_P (SET_DEST (set))
1358 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1362 x = expand_simple_binop (GET_MODE (SET_DEST (set)), PLUS,
1363 new, GEN_INT (offset), SET_DEST (set),
1364 1, OPTAB_LIB_WIDEN);
1365 if (x != SET_DEST (set))
1366 emit_move_insn (SET_DEST (set), x);
1371 emit_insn_before (seq, insn);
1376 extract_insn (insn);
1378 /* Handle a plus involving a virtual register by determining if the
1379 operands remain valid if they're modified in place. */
1380 if (GET_CODE (SET_SRC (set)) == PLUS
1381 && recog_data.n_operands >= 3
1382 && recog_data.operand_loc[1] == &XEXP (SET_SRC (set), 0)
1383 && recog_data.operand_loc[2] == &XEXP (SET_SRC (set), 1)
1384 && GET_CODE (recog_data.operand[2]) == CONST_INT
1385 && (new = instantiate_new_reg (recog_data.operand[1], &offset)))
1387 offset += INTVAL (recog_data.operand[2]);
1389 /* If the sum is zero, then replace with a plain move. */
1393 emit_move_insn (SET_DEST (set), new);
1397 emit_insn_before (seq, insn);
1402 x = gen_int_mode (offset, recog_data.operand_mode[2]);
1403 insn_code = INSN_CODE (insn);
1405 /* Using validate_change and apply_change_group here leaves
1406 recog_data in an invalid state. Since we know exactly what
1407 we want to check, do those two by hand. */
1408 if (safe_insn_predicate (insn_code, 1, new)
1409 && safe_insn_predicate (insn_code, 2, x))
1411 *recog_data.operand_loc[1] = recog_data.operand[1] = new;
1412 *recog_data.operand_loc[2] = recog_data.operand[2] = x;
1419 extract_insn (insn);
1421 insn_code = INSN_CODE (insn);
1424 /* In the general case, we expect virtual registers to appear only in
1425 operands, and then only as either bare registers or inside memories. */
1426 for (i = 0; i < recog_data.n_operands; ++i)
1428 x = recog_data.operand[i];
1429 switch (GET_CODE (x))
1433 rtx addr = XEXP (x, 0);
1434 bool changed = false;
1436 for_each_rtx (&addr, instantiate_virtual_regs_in_rtx, &changed);
1441 x = replace_equiv_address (x, addr);
1445 emit_insn_before (seq, insn);
1450 new = instantiate_new_reg (x, &offset);
1459 /* Careful, special mode predicates may have stuff in
1460 insn_data[insn_code].operand[i].mode that isn't useful
1461 to us for computing a new value. */
1462 /* ??? Recognize address_operand and/or "p" constraints
1463 to see if (plus new offset) is a valid before we put
1464 this through expand_simple_binop. */
1465 x = expand_simple_binop (GET_MODE (x), PLUS, new,
1466 GEN_INT (offset), NULL_RTX,
1467 1, OPTAB_LIB_WIDEN);
1470 emit_insn_before (seq, insn);
1475 new = instantiate_new_reg (SUBREG_REG (x), &offset);
1481 new = expand_simple_binop (GET_MODE (new), PLUS, new,
1482 GEN_INT (offset), NULL_RTX,
1483 1, OPTAB_LIB_WIDEN);
1486 emit_insn_before (seq, insn);
1488 x = simplify_gen_subreg (insn_data[insn_code].operand[i].mode,
1489 new, GET_MODE (new), SUBREG_BYTE (x));
1496 /* At this point, X contains the new value for the operand.
1497 Validate the new value vs the insn predicate. Note that
1498 asm insns will have insn_code -1 here. */
1499 if (!safe_insn_predicate (insn_code, i, x))
1500 x = force_reg (insn_data[insn_code].operand[i].mode, x);
1502 *recog_data.operand_loc[i] = recog_data.operand[i] = x;
1509 /* Propagate operand changes into the duplicates. */
1510 for (i = 0; i < recog_data.n_dups; ++i)
1511 *recog_data.dup_loc[i]
1512 = recog_data.operand[(unsigned)recog_data.dup_num[i]];
1514 /* Force re-recognition of the instruction for validation. */
1515 INSN_CODE (insn) = -1;
1518 if (asm_noperands (PATTERN (insn)) >= 0)
1520 if (!check_asm_operands (PATTERN (insn)))
1522 error_for_asm (insn, "impossible constraint in %<asm%>");
1528 if (recog_memoized (insn) < 0)
1529 fatal_insn_not_found (insn);
1533 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1534 do any instantiation required. */
1537 instantiate_decl (rtx x)
1544 /* If this is a CONCAT, recurse for the pieces. */
1545 if (GET_CODE (x) == CONCAT)
1547 instantiate_decl (XEXP (x, 0));
1548 instantiate_decl (XEXP (x, 1));
1552 /* If this is not a MEM, no need to do anything. Similarly if the
1553 address is a constant or a register that is not a virtual register. */
1558 if (CONSTANT_P (addr)
1560 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
1561 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
1564 for_each_rtx (&XEXP (x, 0), instantiate_virtual_regs_in_rtx, NULL);
1567 /* Subroutine of instantiate_decls: Process all decls in the given
1568 BLOCK node and all its subblocks. */
1571 instantiate_decls_1 (tree let)
1575 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
1576 if (DECL_RTL_SET_P (t))
1577 instantiate_decl (DECL_RTL (t));
1579 /* Process all subblocks. */
1580 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
1581 instantiate_decls_1 (t);
1584 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1585 all virtual registers in their DECL_RTL's. */
1588 instantiate_decls (tree fndecl)
1592 /* Process all parameters of the function. */
1593 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
1595 instantiate_decl (DECL_RTL (decl));
1596 instantiate_decl (DECL_INCOMING_RTL (decl));
1599 /* Now process all variables defined in the function or its subblocks. */
1600 instantiate_decls_1 (DECL_INITIAL (fndecl));
1603 /* Pass through the INSNS of function FNDECL and convert virtual register
1604 references to hard register references. */
1607 instantiate_virtual_regs (void)
1611 /* Compute the offsets to use for this function. */
1612 in_arg_offset = FIRST_PARM_OFFSET (current_function_decl);
1613 var_offset = STARTING_FRAME_OFFSET;
1614 dynamic_offset = STACK_DYNAMIC_OFFSET (current_function_decl);
1615 out_arg_offset = STACK_POINTER_OFFSET;
1616 cfa_offset = ARG_POINTER_CFA_OFFSET (current_function_decl);
1618 /* Initialize recognition, indicating that volatile is OK. */
1621 /* Scan through all the insns, instantiating every virtual register still
1623 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
1626 /* These patterns in the instruction stream can never be recognized.
1627 Fortunately, they shouldn't contain virtual registers either. */
1628 if (GET_CODE (PATTERN (insn)) == USE
1629 || GET_CODE (PATTERN (insn)) == CLOBBER
1630 || GET_CODE (PATTERN (insn)) == ADDR_VEC
1631 || GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC
1632 || GET_CODE (PATTERN (insn)) == ASM_INPUT)
1635 instantiate_virtual_regs_in_insn (insn);
1637 if (INSN_DELETED_P (insn))
1640 for_each_rtx (®_NOTES (insn), instantiate_virtual_regs_in_rtx, NULL);
1642 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1643 if (GET_CODE (insn) == CALL_INSN)
1644 for_each_rtx (&CALL_INSN_FUNCTION_USAGE (insn),
1645 instantiate_virtual_regs_in_rtx, NULL);
1648 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1649 instantiate_decls (current_function_decl);
1651 /* Indicate that, from now on, assign_stack_local should use
1652 frame_pointer_rtx. */
1653 virtuals_instantiated = 1;
1656 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
1657 This means a type for which function calls must pass an address to the
1658 function or get an address back from the function.
1659 EXP may be a type node or an expression (whose type is tested). */
1662 aggregate_value_p (tree exp, tree fntype)
1664 int i, regno, nregs;
1667 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
1670 switch (TREE_CODE (fntype))
1673 fntype = get_callee_fndecl (fntype);
1674 fntype = fntype ? TREE_TYPE (fntype) : 0;
1677 fntype = TREE_TYPE (fntype);
1682 case IDENTIFIER_NODE:
1686 /* We don't expect other rtl types here. */
1690 if (TREE_CODE (type) == VOID_TYPE)
1692 /* If the front end has decided that this needs to be passed by
1693 reference, do so. */
1694 if ((TREE_CODE (exp) == PARM_DECL || TREE_CODE (exp) == RESULT_DECL)
1695 && DECL_BY_REFERENCE (exp))
1697 if (targetm.calls.return_in_memory (type, fntype))
1699 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
1700 and thus can't be returned in registers. */
1701 if (TREE_ADDRESSABLE (type))
1703 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
1705 /* Make sure we have suitable call-clobbered regs to return
1706 the value in; if not, we must return it in memory. */
1707 reg = hard_function_value (type, 0, 0);
1709 /* If we have something other than a REG (e.g. a PARALLEL), then assume
1714 regno = REGNO (reg);
1715 nregs = hard_regno_nregs[regno][TYPE_MODE (type)];
1716 for (i = 0; i < nregs; i++)
1717 if (! call_used_regs[regno + i])
1722 /* Return true if we should assign DECL a pseudo register; false if it
1723 should live on the local stack. */
1726 use_register_for_decl (tree decl)
1728 /* Honor volatile. */
1729 if (TREE_SIDE_EFFECTS (decl))
1732 /* Honor addressability. */
1733 if (TREE_ADDRESSABLE (decl))
1736 /* Only register-like things go in registers. */
1737 if (DECL_MODE (decl) == BLKmode)
1740 /* If -ffloat-store specified, don't put explicit float variables
1742 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
1743 propagates values across these stores, and it probably shouldn't. */
1744 if (flag_float_store && FLOAT_TYPE_P (TREE_TYPE (decl)))
1747 /* If we're not interested in tracking debugging information for
1748 this decl, then we can certainly put it in a register. */
1749 if (DECL_IGNORED_P (decl))
1752 return (optimize || DECL_REGISTER (decl));
1755 /* Return true if TYPE should be passed by invisible reference. */
1758 pass_by_reference (CUMULATIVE_ARGS *ca, enum machine_mode mode,
1759 tree type, bool named_arg)
1763 /* If this type contains non-trivial constructors, then it is
1764 forbidden for the middle-end to create any new copies. */
1765 if (TREE_ADDRESSABLE (type))
1768 /* GCC post 3.4 passes *all* variable sized types by reference. */
1769 if (!TYPE_SIZE (type) || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
1773 return targetm.calls.pass_by_reference (ca, mode, type, named_arg);
1776 /* Return true if TYPE, which is passed by reference, should be callee
1777 copied instead of caller copied. */
1780 reference_callee_copied (CUMULATIVE_ARGS *ca, enum machine_mode mode,
1781 tree type, bool named_arg)
1783 if (type && TREE_ADDRESSABLE (type))
1785 return targetm.calls.callee_copies (ca, mode, type, named_arg);
1788 /* Structures to communicate between the subroutines of assign_parms.
1789 The first holds data persistent across all parameters, the second
1790 is cleared out for each parameter. */
1792 struct assign_parm_data_all
1794 CUMULATIVE_ARGS args_so_far;
1795 struct args_size stack_args_size;
1796 tree function_result_decl;
1798 rtx conversion_insns;
1799 HOST_WIDE_INT pretend_args_size;
1800 HOST_WIDE_INT extra_pretend_bytes;
1801 int reg_parm_stack_space;
1804 struct assign_parm_data_one
1810 enum machine_mode nominal_mode;
1811 enum machine_mode passed_mode;
1812 enum machine_mode promoted_mode;
1813 struct locate_and_pad_arg_data locate;
1815 BOOL_BITFIELD named_arg : 1;
1816 BOOL_BITFIELD passed_pointer : 1;
1817 BOOL_BITFIELD on_stack : 1;
1818 BOOL_BITFIELD loaded_in_reg : 1;
1821 /* A subroutine of assign_parms. Initialize ALL. */
1824 assign_parms_initialize_all (struct assign_parm_data_all *all)
1828 memset (all, 0, sizeof (*all));
1830 fntype = TREE_TYPE (current_function_decl);
1832 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
1833 INIT_CUMULATIVE_INCOMING_ARGS (all->args_so_far, fntype, NULL_RTX);
1835 INIT_CUMULATIVE_ARGS (all->args_so_far, fntype, NULL_RTX,
1836 current_function_decl, -1);
1839 #ifdef REG_PARM_STACK_SPACE
1840 all->reg_parm_stack_space = REG_PARM_STACK_SPACE (current_function_decl);
1844 /* If ARGS contains entries with complex types, split the entry into two
1845 entries of the component type. Return a new list of substitutions are
1846 needed, else the old list. */
1849 split_complex_args (tree args)
1853 /* Before allocating memory, check for the common case of no complex. */
1854 for (p = args; p; p = TREE_CHAIN (p))
1856 tree type = TREE_TYPE (p);
1857 if (TREE_CODE (type) == COMPLEX_TYPE
1858 && targetm.calls.split_complex_arg (type))
1864 args = copy_list (args);
1866 for (p = args; p; p = TREE_CHAIN (p))
1868 tree type = TREE_TYPE (p);
1869 if (TREE_CODE (type) == COMPLEX_TYPE
1870 && targetm.calls.split_complex_arg (type))
1873 tree subtype = TREE_TYPE (type);
1874 bool addressable = TREE_ADDRESSABLE (p);
1876 /* Rewrite the PARM_DECL's type with its component. */
1877 TREE_TYPE (p) = subtype;
1878 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
1879 DECL_MODE (p) = VOIDmode;
1880 DECL_SIZE (p) = NULL;
1881 DECL_SIZE_UNIT (p) = NULL;
1882 /* If this arg must go in memory, put it in a pseudo here.
1883 We can't allow it to go in memory as per normal parms,
1884 because the usual place might not have the imag part
1885 adjacent to the real part. */
1886 DECL_ARTIFICIAL (p) = addressable;
1887 DECL_IGNORED_P (p) = addressable;
1888 TREE_ADDRESSABLE (p) = 0;
1891 /* Build a second synthetic decl. */
1892 decl = build_decl (PARM_DECL, NULL_TREE, subtype);
1893 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
1894 DECL_ARTIFICIAL (decl) = addressable;
1895 DECL_IGNORED_P (decl) = addressable;
1896 layout_decl (decl, 0);
1898 /* Splice it in; skip the new decl. */
1899 TREE_CHAIN (decl) = TREE_CHAIN (p);
1900 TREE_CHAIN (p) = decl;
1908 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
1909 the hidden struct return argument, and (abi willing) complex args.
1910 Return the new parameter list. */
1913 assign_parms_augmented_arg_list (struct assign_parm_data_all *all)
1915 tree fndecl = current_function_decl;
1916 tree fntype = TREE_TYPE (fndecl);
1917 tree fnargs = DECL_ARGUMENTS (fndecl);
1919 /* If struct value address is treated as the first argument, make it so. */
1920 if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
1921 && ! current_function_returns_pcc_struct
1922 && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
1924 tree type = build_pointer_type (TREE_TYPE (fntype));
1927 decl = build_decl (PARM_DECL, NULL_TREE, type);
1928 DECL_ARG_TYPE (decl) = type;
1929 DECL_ARTIFICIAL (decl) = 1;
1930 DECL_IGNORED_P (decl) = 1;
1932 TREE_CHAIN (decl) = fnargs;
1934 all->function_result_decl = decl;
1937 all->orig_fnargs = fnargs;
1939 /* If the target wants to split complex arguments into scalars, do so. */
1940 if (targetm.calls.split_complex_arg)
1941 fnargs = split_complex_args (fnargs);
1946 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
1947 data for the parameter. Incorporate ABI specifics such as pass-by-
1948 reference and type promotion. */
1951 assign_parm_find_data_types (struct assign_parm_data_all *all, tree parm,
1952 struct assign_parm_data_one *data)
1954 tree nominal_type, passed_type;
1955 enum machine_mode nominal_mode, passed_mode, promoted_mode;
1957 memset (data, 0, sizeof (*data));
1959 /* NAMED_ARG is a mis-nomer. We really mean 'non-varadic'. */
1960 if (!current_function_stdarg)
1961 data->named_arg = 1; /* No varadic parms. */
1962 else if (TREE_CHAIN (parm))
1963 data->named_arg = 1; /* Not the last non-varadic parm. */
1964 else if (targetm.calls.strict_argument_naming (&all->args_so_far))
1965 data->named_arg = 1; /* Only varadic ones are unnamed. */
1967 data->named_arg = 0; /* Treat as varadic. */
1969 nominal_type = TREE_TYPE (parm);
1970 passed_type = DECL_ARG_TYPE (parm);
1972 /* Look out for errors propagating this far. Also, if the parameter's
1973 type is void then its value doesn't matter. */
1974 if (TREE_TYPE (parm) == error_mark_node
1975 /* This can happen after weird syntax errors
1976 or if an enum type is defined among the parms. */
1977 || TREE_CODE (parm) != PARM_DECL
1978 || passed_type == NULL
1979 || VOID_TYPE_P (nominal_type))
1981 nominal_type = passed_type = void_type_node;
1982 nominal_mode = passed_mode = promoted_mode = VOIDmode;
1986 /* Find mode of arg as it is passed, and mode of arg as it should be
1987 during execution of this function. */
1988 passed_mode = TYPE_MODE (passed_type);
1989 nominal_mode = TYPE_MODE (nominal_type);
1991 /* If the parm is to be passed as a transparent union, use the type of
1992 the first field for the tests below. We have already verified that
1993 the modes are the same. */
1994 if (DECL_TRANSPARENT_UNION (parm)
1995 || (TREE_CODE (passed_type) == UNION_TYPE
1996 && TYPE_TRANSPARENT_UNION (passed_type)))
1997 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
1999 /* See if this arg was passed by invisible reference. */
2000 if (pass_by_reference (&all->args_so_far, passed_mode,
2001 passed_type, data->named_arg))
2003 passed_type = nominal_type = build_pointer_type (passed_type);
2004 data->passed_pointer = true;
2005 passed_mode = nominal_mode = Pmode;
2008 /* Find mode as it is passed by the ABI. */
2009 promoted_mode = passed_mode;
2010 if (targetm.calls.promote_function_args (TREE_TYPE (current_function_decl)))
2012 int unsignedp = TYPE_UNSIGNED (passed_type);
2013 promoted_mode = promote_mode (passed_type, promoted_mode,
2018 data->nominal_type = nominal_type;
2019 data->passed_type = passed_type;
2020 data->nominal_mode = nominal_mode;
2021 data->passed_mode = passed_mode;
2022 data->promoted_mode = promoted_mode;
2025 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2028 assign_parms_setup_varargs (struct assign_parm_data_all *all,
2029 struct assign_parm_data_one *data, bool no_rtl)
2031 int varargs_pretend_bytes = 0;
2033 targetm.calls.setup_incoming_varargs (&all->args_so_far,
2034 data->promoted_mode,
2036 &varargs_pretend_bytes, no_rtl);
2038 /* If the back-end has requested extra stack space, record how much is
2039 needed. Do not change pretend_args_size otherwise since it may be
2040 nonzero from an earlier partial argument. */
2041 if (varargs_pretend_bytes > 0)
2042 all->pretend_args_size = varargs_pretend_bytes;
2045 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2046 the incoming location of the current parameter. */
2049 assign_parm_find_entry_rtl (struct assign_parm_data_all *all,
2050 struct assign_parm_data_one *data)
2052 HOST_WIDE_INT pretend_bytes = 0;
2056 if (data->promoted_mode == VOIDmode)
2058 data->entry_parm = data->stack_parm = const0_rtx;
2062 #ifdef FUNCTION_INCOMING_ARG
2063 entry_parm = FUNCTION_INCOMING_ARG (all->args_so_far, data->promoted_mode,
2064 data->passed_type, data->named_arg);
2066 entry_parm = FUNCTION_ARG (all->args_so_far, data->promoted_mode,
2067 data->passed_type, data->named_arg);
2070 if (entry_parm == 0)
2071 data->promoted_mode = data->passed_mode;
2073 /* Determine parm's home in the stack, in case it arrives in the stack
2074 or we should pretend it did. Compute the stack position and rtx where
2075 the argument arrives and its size.
2077 There is one complexity here: If this was a parameter that would
2078 have been passed in registers, but wasn't only because it is
2079 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2080 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2081 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2082 as it was the previous time. */
2083 in_regs = entry_parm != 0;
2084 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2087 if (!in_regs && !data->named_arg)
2089 if (targetm.calls.pretend_outgoing_varargs_named (&all->args_so_far))
2092 #ifdef FUNCTION_INCOMING_ARG
2093 tem = FUNCTION_INCOMING_ARG (all->args_so_far, data->promoted_mode,
2094 data->passed_type, true);
2096 tem = FUNCTION_ARG (all->args_so_far, data->promoted_mode,
2097 data->passed_type, true);
2099 in_regs = tem != NULL;
2103 /* If this parameter was passed both in registers and in the stack, use
2104 the copy on the stack. */
2105 if (targetm.calls.must_pass_in_stack (data->promoted_mode,
2113 partial = targetm.calls.arg_partial_bytes (&all->args_so_far,
2114 data->promoted_mode,
2117 data->partial = partial;
2119 /* The caller might already have allocated stack space for the
2120 register parameters. */
2121 if (partial != 0 && all->reg_parm_stack_space == 0)
2123 /* Part of this argument is passed in registers and part
2124 is passed on the stack. Ask the prologue code to extend
2125 the stack part so that we can recreate the full value.
2127 PRETEND_BYTES is the size of the registers we need to store.
2128 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2129 stack space that the prologue should allocate.
2131 Internally, gcc assumes that the argument pointer is aligned
2132 to STACK_BOUNDARY bits. This is used both for alignment
2133 optimizations (see init_emit) and to locate arguments that are
2134 aligned to more than PARM_BOUNDARY bits. We must preserve this
2135 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2136 a stack boundary. */
2138 /* We assume at most one partial arg, and it must be the first
2139 argument on the stack. */
2140 gcc_assert (!all->extra_pretend_bytes && !all->pretend_args_size);
2142 pretend_bytes = partial;
2143 all->pretend_args_size = CEIL_ROUND (pretend_bytes, STACK_BYTES);
2145 /* We want to align relative to the actual stack pointer, so
2146 don't include this in the stack size until later. */
2147 all->extra_pretend_bytes = all->pretend_args_size;
2151 locate_and_pad_parm (data->promoted_mode, data->passed_type, in_regs,
2152 entry_parm ? data->partial : 0, current_function_decl,
2153 &all->stack_args_size, &data->locate);
2155 /* Adjust offsets to include the pretend args. */
2156 pretend_bytes = all->extra_pretend_bytes - pretend_bytes;
2157 data->locate.slot_offset.constant += pretend_bytes;
2158 data->locate.offset.constant += pretend_bytes;
2160 data->entry_parm = entry_parm;
2163 /* A subroutine of assign_parms. If there is actually space on the stack
2164 for this parm, count it in stack_args_size and return true. */
2167 assign_parm_is_stack_parm (struct assign_parm_data_all *all,
2168 struct assign_parm_data_one *data)
2170 /* Trivially true if we've no incoming register. */
2171 if (data->entry_parm == NULL)
2173 /* Also true if we're partially in registers and partially not,
2174 since we've arranged to drop the entire argument on the stack. */
2175 else if (data->partial != 0)
2177 /* Also true if the target says that it's passed in both registers
2178 and on the stack. */
2179 else if (GET_CODE (data->entry_parm) == PARALLEL
2180 && XEXP (XVECEXP (data->entry_parm, 0, 0), 0) == NULL_RTX)
2182 /* Also true if the target says that there's stack allocated for
2183 all register parameters. */
2184 else if (all->reg_parm_stack_space > 0)
2186 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2190 all->stack_args_size.constant += data->locate.size.constant;
2191 if (data->locate.size.var)
2192 ADD_PARM_SIZE (all->stack_args_size, data->locate.size.var);
2197 /* A subroutine of assign_parms. Given that this parameter is allocated
2198 stack space by the ABI, find it. */
2201 assign_parm_find_stack_rtl (tree parm, struct assign_parm_data_one *data)
2203 rtx offset_rtx, stack_parm;
2204 unsigned int align, boundary;
2206 /* If we're passing this arg using a reg, make its stack home the
2207 aligned stack slot. */
2208 if (data->entry_parm)
2209 offset_rtx = ARGS_SIZE_RTX (data->locate.slot_offset);
2211 offset_rtx = ARGS_SIZE_RTX (data->locate.offset);
2213 stack_parm = current_function_internal_arg_pointer;
2214 if (offset_rtx != const0_rtx)
2215 stack_parm = gen_rtx_PLUS (Pmode, stack_parm, offset_rtx);
2216 stack_parm = gen_rtx_MEM (data->promoted_mode, stack_parm);
2218 set_mem_attributes (stack_parm, parm, 1);
2220 boundary = data->locate.boundary;
2221 align = BITS_PER_UNIT;
2223 /* If we're padding upward, we know that the alignment of the slot
2224 is FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2225 intentionally forcing upward padding. Otherwise we have to come
2226 up with a guess at the alignment based on OFFSET_RTX. */
2227 if (data->locate.where_pad != downward || data->entry_parm)
2229 else if (GET_CODE (offset_rtx) == CONST_INT)
2231 align = INTVAL (offset_rtx) * BITS_PER_UNIT | boundary;
2232 align = align & -align;
2234 set_mem_align (stack_parm, align);
2236 if (data->entry_parm)
2237 set_reg_attrs_for_parm (data->entry_parm, stack_parm);
2239 data->stack_parm = stack_parm;
2242 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2243 always valid and contiguous. */
2246 assign_parm_adjust_entry_rtl (struct assign_parm_data_one *data)
2248 rtx entry_parm = data->entry_parm;
2249 rtx stack_parm = data->stack_parm;
2251 /* If this parm was passed part in regs and part in memory, pretend it
2252 arrived entirely in memory by pushing the register-part onto the stack.
2253 In the special case of a DImode or DFmode that is split, we could put
2254 it together in a pseudoreg directly, but for now that's not worth
2256 if (data->partial != 0)
2258 /* Handle calls that pass values in multiple non-contiguous
2259 locations. The Irix 6 ABI has examples of this. */
2260 if (GET_CODE (entry_parm) == PARALLEL)
2261 emit_group_store (validize_mem (stack_parm), entry_parm,
2263 int_size_in_bytes (data->passed_type));
2266 gcc_assert (data->partial % UNITS_PER_WORD == 0);
2267 move_block_from_reg (REGNO (entry_parm), validize_mem (stack_parm),
2268 data->partial / UNITS_PER_WORD);
2271 entry_parm = stack_parm;
2274 /* If we didn't decide this parm came in a register, by default it came
2276 else if (entry_parm == NULL)
2277 entry_parm = stack_parm;
2279 /* When an argument is passed in multiple locations, we can't make use
2280 of this information, but we can save some copying if the whole argument
2281 is passed in a single register. */
2282 else if (GET_CODE (entry_parm) == PARALLEL
2283 && data->nominal_mode != BLKmode
2284 && data->passed_mode != BLKmode)
2286 size_t i, len = XVECLEN (entry_parm, 0);
2288 for (i = 0; i < len; i++)
2289 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
2290 && REG_P (XEXP (XVECEXP (entry_parm, 0, i), 0))
2291 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
2292 == data->passed_mode)
2293 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
2295 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
2300 data->entry_parm = entry_parm;
2303 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2304 always valid and properly aligned. */
2307 assign_parm_adjust_stack_rtl (struct assign_parm_data_one *data)
2309 rtx stack_parm = data->stack_parm;
2311 /* If we can't trust the parm stack slot to be aligned enough for its
2312 ultimate type, don't use that slot after entry. We'll make another
2313 stack slot, if we need one. */
2315 && ((STRICT_ALIGNMENT
2316 && GET_MODE_ALIGNMENT (data->nominal_mode) > MEM_ALIGN (stack_parm))
2317 || (data->nominal_type
2318 && TYPE_ALIGN (data->nominal_type) > MEM_ALIGN (stack_parm)
2319 && MEM_ALIGN (stack_parm) < PREFERRED_STACK_BOUNDARY)))
2322 /* If parm was passed in memory, and we need to convert it on entry,
2323 don't store it back in that same slot. */
2324 else if (data->entry_parm == stack_parm
2325 && data->nominal_mode != BLKmode
2326 && data->nominal_mode != data->passed_mode)
2329 data->stack_parm = stack_parm;
2332 /* A subroutine of assign_parms. Return true if the current parameter
2333 should be stored as a BLKmode in the current frame. */
2336 assign_parm_setup_block_p (struct assign_parm_data_one *data)
2338 if (data->nominal_mode == BLKmode)
2340 if (GET_CODE (data->entry_parm) == PARALLEL)
2343 #ifdef BLOCK_REG_PADDING
2344 /* Only assign_parm_setup_block knows how to deal with register arguments
2345 that are padded at the least significant end. */
2346 if (REG_P (data->entry_parm)
2347 && GET_MODE_SIZE (data->promoted_mode) < UNITS_PER_WORD
2348 && (BLOCK_REG_PADDING (data->passed_mode, data->passed_type, 1)
2349 == (BYTES_BIG_ENDIAN ? upward : downward)))
2356 /* A subroutine of assign_parms. Arrange for the parameter to be
2357 present and valid in DATA->STACK_RTL. */
2360 assign_parm_setup_block (struct assign_parm_data_all *all,
2361 tree parm, struct assign_parm_data_one *data)
2363 rtx entry_parm = data->entry_parm;
2364 rtx stack_parm = data->stack_parm;
2366 HOST_WIDE_INT size_stored;
2367 rtx orig_entry_parm = entry_parm;
2369 if (GET_CODE (entry_parm) == PARALLEL)
2370 entry_parm = emit_group_move_into_temps (entry_parm);
2372 /* If we've a non-block object that's nevertheless passed in parts,
2373 reconstitute it in register operations rather than on the stack. */
2374 if (GET_CODE (entry_parm) == PARALLEL
2375 && data->nominal_mode != BLKmode)
2377 rtx elt0 = XEXP (XVECEXP (orig_entry_parm, 0, 0), 0);
2379 if ((XVECLEN (entry_parm, 0) > 1
2380 || hard_regno_nregs[REGNO (elt0)][GET_MODE (elt0)] > 1)
2381 && use_register_for_decl (parm))
2383 rtx parmreg = gen_reg_rtx (data->nominal_mode);
2385 push_to_sequence (all->conversion_insns);
2387 /* For values returned in multiple registers, handle possible
2388 incompatible calls to emit_group_store.
2390 For example, the following would be invalid, and would have to
2391 be fixed by the conditional below:
2393 emit_group_store ((reg:SF), (parallel:DF))
2394 emit_group_store ((reg:SI), (parallel:DI))
2396 An example of this are doubles in e500 v2:
2397 (parallel:DF (expr_list (reg:SI) (const_int 0))
2398 (expr_list (reg:SI) (const_int 4))). */
2399 if (data->nominal_mode != data->passed_mode)
2401 rtx t = gen_reg_rtx (GET_MODE (entry_parm));
2402 emit_group_store (t, entry_parm, NULL_TREE,
2403 GET_MODE_SIZE (GET_MODE (entry_parm)));
2404 convert_move (parmreg, t, 0);
2407 emit_group_store (parmreg, entry_parm, data->nominal_type,
2408 int_size_in_bytes (data->nominal_type));
2410 all->conversion_insns = get_insns ();
2413 SET_DECL_RTL (parm, parmreg);
2418 size = int_size_in_bytes (data->passed_type);
2419 size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
2420 if (stack_parm == 0)
2422 DECL_ALIGN (parm) = MAX (DECL_ALIGN (parm), BITS_PER_WORD);
2423 stack_parm = assign_stack_local (BLKmode, size_stored,
2425 if (GET_MODE_SIZE (GET_MODE (entry_parm)) == size)
2426 PUT_MODE (stack_parm, GET_MODE (entry_parm));
2427 set_mem_attributes (stack_parm, parm, 1);
2430 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2431 calls that pass values in multiple non-contiguous locations. */
2432 if (REG_P (entry_parm) || GET_CODE (entry_parm) == PARALLEL)
2436 /* Note that we will be storing an integral number of words.
2437 So we have to be careful to ensure that we allocate an
2438 integral number of words. We do this above when we call
2439 assign_stack_local if space was not allocated in the argument
2440 list. If it was, this will not work if PARM_BOUNDARY is not
2441 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2442 if it becomes a problem. Exception is when BLKmode arrives
2443 with arguments not conforming to word_mode. */
2445 if (data->stack_parm == 0)
2447 else if (GET_CODE (entry_parm) == PARALLEL)
2450 gcc_assert (!size || !(PARM_BOUNDARY % BITS_PER_WORD));
2452 mem = validize_mem (stack_parm);
2454 /* Handle values in multiple non-contiguous locations. */
2455 if (GET_CODE (entry_parm) == PARALLEL)
2457 push_to_sequence (all->conversion_insns);
2458 emit_group_store (mem, entry_parm, data->passed_type, size);
2459 all->conversion_insns = get_insns ();
2466 /* If SIZE is that of a mode no bigger than a word, just use
2467 that mode's store operation. */
2468 else if (size <= UNITS_PER_WORD)
2470 enum machine_mode mode
2471 = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
2474 #ifdef BLOCK_REG_PADDING
2475 && (size == UNITS_PER_WORD
2476 || (BLOCK_REG_PADDING (mode, data->passed_type, 1)
2477 != (BYTES_BIG_ENDIAN ? upward : downward)))
2481 rtx reg = gen_rtx_REG (mode, REGNO (entry_parm));
2482 emit_move_insn (change_address (mem, mode, 0), reg);
2485 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
2486 machine must be aligned to the left before storing
2487 to memory. Note that the previous test doesn't
2488 handle all cases (e.g. SIZE == 3). */
2489 else if (size != UNITS_PER_WORD
2490 #ifdef BLOCK_REG_PADDING
2491 && (BLOCK_REG_PADDING (mode, data->passed_type, 1)
2499 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2500 rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
2502 x = expand_shift (LSHIFT_EXPR, word_mode, reg,
2503 build_int_cst (NULL_TREE, by),
2505 tem = change_address (mem, word_mode, 0);
2506 emit_move_insn (tem, x);
2509 move_block_from_reg (REGNO (entry_parm), mem,
2510 size_stored / UNITS_PER_WORD);
2513 move_block_from_reg (REGNO (entry_parm), mem,
2514 size_stored / UNITS_PER_WORD);
2516 else if (data->stack_parm == 0)
2518 push_to_sequence (all->conversion_insns);
2519 emit_block_move (stack_parm, data->entry_parm, GEN_INT (size),
2521 all->conversion_insns = get_insns ();
2525 data->stack_parm = stack_parm;
2526 SET_DECL_RTL (parm, stack_parm);
2529 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
2530 parameter. Get it there. Perform all ABI specified conversions. */
2533 assign_parm_setup_reg (struct assign_parm_data_all *all, tree parm,
2534 struct assign_parm_data_one *data)
2537 enum machine_mode promoted_nominal_mode;
2538 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (parm));
2539 bool did_conversion = false;
2541 /* Store the parm in a pseudoregister during the function, but we may
2542 need to do it in a wider mode. */
2544 promoted_nominal_mode
2545 = promote_mode (data->nominal_type, data->nominal_mode, &unsignedp, 0);
2547 parmreg = gen_reg_rtx (promoted_nominal_mode);
2549 if (!DECL_ARTIFICIAL (parm))
2550 mark_user_reg (parmreg);
2552 /* If this was an item that we received a pointer to,
2553 set DECL_RTL appropriately. */
2554 if (data->passed_pointer)
2556 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data->passed_type)), parmreg);
2557 set_mem_attributes (x, parm, 1);
2558 SET_DECL_RTL (parm, x);
2561 SET_DECL_RTL (parm, parmreg);
2563 /* Copy the value into the register. */
2564 if (data->nominal_mode != data->passed_mode
2565 || promoted_nominal_mode != data->promoted_mode)
2569 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
2570 mode, by the caller. We now have to convert it to
2571 NOMINAL_MODE, if different. However, PARMREG may be in
2572 a different mode than NOMINAL_MODE if it is being stored
2575 If ENTRY_PARM is a hard register, it might be in a register
2576 not valid for operating in its mode (e.g., an odd-numbered
2577 register for a DFmode). In that case, moves are the only
2578 thing valid, so we can't do a convert from there. This
2579 occurs when the calling sequence allow such misaligned
2582 In addition, the conversion may involve a call, which could
2583 clobber parameters which haven't been copied to pseudo
2584 registers yet. Therefore, we must first copy the parm to
2585 a pseudo reg here, and save the conversion until after all
2586 parameters have been moved. */
2588 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
2590 emit_move_insn (tempreg, validize_mem (data->entry_parm));
2592 push_to_sequence (all->conversion_insns);
2593 tempreg = convert_to_mode (data->nominal_mode, tempreg, unsignedp);
2595 if (GET_CODE (tempreg) == SUBREG
2596 && GET_MODE (tempreg) == data->nominal_mode
2597 && REG_P (SUBREG_REG (tempreg))
2598 && data->nominal_mode == data->passed_mode
2599 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (data->entry_parm)
2600 && GET_MODE_SIZE (GET_MODE (tempreg))
2601 < GET_MODE_SIZE (GET_MODE (data->entry_parm)))
2603 /* The argument is already sign/zero extended, so note it
2605 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
2606 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
2609 /* TREE_USED gets set erroneously during expand_assignment. */
2610 save_tree_used = TREE_USED (parm);
2611 expand_assignment (parm, make_tree (data->nominal_type, tempreg));
2612 TREE_USED (parm) = save_tree_used;
2613 all->conversion_insns = get_insns ();
2616 did_conversion = true;
2619 emit_move_insn (parmreg, validize_mem (data->entry_parm));
2621 /* If we were passed a pointer but the actual value can safely live
2622 in a register, put it in one. */
2623 if (data->passed_pointer
2624 && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
2625 /* If by-reference argument was promoted, demote it. */
2626 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
2627 || use_register_for_decl (parm)))
2629 /* We can't use nominal_mode, because it will have been set to
2630 Pmode above. We must use the actual mode of the parm. */
2631 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
2632 mark_user_reg (parmreg);
2634 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
2636 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
2637 int unsigned_p = TYPE_UNSIGNED (TREE_TYPE (parm));
2639 push_to_sequence (all->conversion_insns);
2640 emit_move_insn (tempreg, DECL_RTL (parm));
2641 tempreg = convert_to_mode (GET_MODE (parmreg), tempreg, unsigned_p);
2642 emit_move_insn (parmreg, tempreg);
2643 all->conversion_insns = get_insns ();
2646 did_conversion = true;
2649 emit_move_insn (parmreg, DECL_RTL (parm));
2651 SET_DECL_RTL (parm, parmreg);
2653 /* STACK_PARM is the pointer, not the parm, and PARMREG is
2655 data->stack_parm = NULL;
2658 /* Mark the register as eliminable if we did no conversion and it was
2659 copied from memory at a fixed offset, and the arg pointer was not
2660 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
2661 offset formed an invalid address, such memory-equivalences as we
2662 make here would screw up life analysis for it. */
2663 if (data->nominal_mode == data->passed_mode
2665 && data->stack_parm != 0
2666 && MEM_P (data->stack_parm)
2667 && data->locate.offset.var == 0
2668 && reg_mentioned_p (virtual_incoming_args_rtx,
2669 XEXP (data->stack_parm, 0)))
2671 rtx linsn = get_last_insn ();
2674 /* Mark complex types separately. */
2675 if (GET_CODE (parmreg) == CONCAT)
2677 enum machine_mode submode
2678 = GET_MODE_INNER (GET_MODE (parmreg));
2679 int regnor = REGNO (XEXP (parmreg, 0));
2680 int regnoi = REGNO (XEXP (parmreg, 1));
2681 rtx stackr = adjust_address_nv (data->stack_parm, submode, 0);
2682 rtx stacki = adjust_address_nv (data->stack_parm, submode,
2683 GET_MODE_SIZE (submode));
2685 /* Scan backwards for the set of the real and
2687 for (sinsn = linsn; sinsn != 0;
2688 sinsn = prev_nonnote_insn (sinsn))
2690 set = single_set (sinsn);
2694 if (SET_DEST (set) == regno_reg_rtx [regnoi])
2696 = gen_rtx_EXPR_LIST (REG_EQUIV, stacki,
2698 else if (SET_DEST (set) == regno_reg_rtx [regnor])
2700 = gen_rtx_EXPR_LIST (REG_EQUIV, stackr,
2704 else if ((set = single_set (linsn)) != 0
2705 && SET_DEST (set) == parmreg)
2707 = gen_rtx_EXPR_LIST (REG_EQUIV,
2708 data->stack_parm, REG_NOTES (linsn));
2711 /* For pointer data type, suggest pointer register. */
2712 if (POINTER_TYPE_P (TREE_TYPE (parm)))
2713 mark_reg_pointer (parmreg,
2714 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
2717 /* A subroutine of assign_parms. Allocate stack space to hold the current
2718 parameter. Get it there. Perform all ABI specified conversions. */
2721 assign_parm_setup_stack (struct assign_parm_data_all *all, tree parm,
2722 struct assign_parm_data_one *data)
2724 /* Value must be stored in the stack slot STACK_PARM during function
2726 bool to_conversion = false;
2728 if (data->promoted_mode != data->nominal_mode)
2730 /* Conversion is required. */
2731 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
2733 emit_move_insn (tempreg, validize_mem (data->entry_parm));
2735 push_to_sequence (all->conversion_insns);
2736 to_conversion = true;
2738 data->entry_parm = convert_to_mode (data->nominal_mode, tempreg,
2739 TYPE_UNSIGNED (TREE_TYPE (parm)));
2741 if (data->stack_parm)
2742 /* ??? This may need a big-endian conversion on sparc64. */
2744 = adjust_address (data->stack_parm, data->nominal_mode, 0);
2747 if (data->entry_parm != data->stack_parm)
2751 if (data->stack_parm == 0)
2754 = assign_stack_local (GET_MODE (data->entry_parm),
2755 GET_MODE_SIZE (GET_MODE (data->entry_parm)),
2756 TYPE_ALIGN (data->passed_type));
2757 set_mem_attributes (data->stack_parm, parm, 1);
2760 dest = validize_mem (data->stack_parm);
2761 src = validize_mem (data->entry_parm);
2765 /* Use a block move to handle potentially misaligned entry_parm. */
2767 push_to_sequence (all->conversion_insns);
2768 to_conversion = true;
2770 emit_block_move (dest, src,
2771 GEN_INT (int_size_in_bytes (data->passed_type)),
2775 emit_move_insn (dest, src);
2780 all->conversion_insns = get_insns ();
2784 SET_DECL_RTL (parm, data->stack_parm);
2787 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
2788 undo the frobbing that we did in assign_parms_augmented_arg_list. */
2791 assign_parms_unsplit_complex (struct assign_parm_data_all *all, tree fnargs)
2794 tree orig_fnargs = all->orig_fnargs;
2796 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm))
2798 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE
2799 && targetm.calls.split_complex_arg (TREE_TYPE (parm)))
2801 rtx tmp, real, imag;
2802 enum machine_mode inner = GET_MODE_INNER (DECL_MODE (parm));
2804 real = DECL_RTL (fnargs);
2805 imag = DECL_RTL (TREE_CHAIN (fnargs));
2806 if (inner != GET_MODE (real))
2808 real = gen_lowpart_SUBREG (inner, real);
2809 imag = gen_lowpart_SUBREG (inner, imag);
2812 if (TREE_ADDRESSABLE (parm))
2815 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (parm));
2817 /* split_complex_arg put the real and imag parts in
2818 pseudos. Move them to memory. */
2819 tmp = assign_stack_local (DECL_MODE (parm), size,
2820 TYPE_ALIGN (TREE_TYPE (parm)));
2821 set_mem_attributes (tmp, parm, 1);
2822 rmem = adjust_address_nv (tmp, inner, 0);
2823 imem = adjust_address_nv (tmp, inner, GET_MODE_SIZE (inner));
2824 push_to_sequence (all->conversion_insns);
2825 emit_move_insn (rmem, real);
2826 emit_move_insn (imem, imag);
2827 all->conversion_insns = get_insns ();
2831 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
2832 SET_DECL_RTL (parm, tmp);
2834 real = DECL_INCOMING_RTL (fnargs);
2835 imag = DECL_INCOMING_RTL (TREE_CHAIN (fnargs));
2836 if (inner != GET_MODE (real))
2838 real = gen_lowpart_SUBREG (inner, real);
2839 imag = gen_lowpart_SUBREG (inner, imag);
2841 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
2842 set_decl_incoming_rtl (parm, tmp);
2843 fnargs = TREE_CHAIN (fnargs);
2847 SET_DECL_RTL (parm, DECL_RTL (fnargs));
2848 set_decl_incoming_rtl (parm, DECL_INCOMING_RTL (fnargs));
2850 /* Set MEM_EXPR to the original decl, i.e. to PARM,
2851 instead of the copy of decl, i.e. FNARGS. */
2852 if (DECL_INCOMING_RTL (parm) && MEM_P (DECL_INCOMING_RTL (parm)))
2853 set_mem_expr (DECL_INCOMING_RTL (parm), parm);
2856 fnargs = TREE_CHAIN (fnargs);
2860 /* Assign RTL expressions to the function's parameters. This may involve
2861 copying them into registers and using those registers as the DECL_RTL. */
2864 assign_parms (tree fndecl)
2866 struct assign_parm_data_all all;
2868 rtx internal_arg_pointer;
2870 /* If the reg that the virtual arg pointer will be translated into is
2871 not a fixed reg or is the stack pointer, make a copy of the virtual
2872 arg pointer, and address parms via the copy. The frame pointer is
2873 considered fixed even though it is not marked as such.
2875 The second time through, simply use ap to avoid generating rtx. */
2877 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
2878 || ! (fixed_regs[ARG_POINTER_REGNUM]
2879 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
2880 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
2882 internal_arg_pointer = virtual_incoming_args_rtx;
2883 current_function_internal_arg_pointer = internal_arg_pointer;
2885 assign_parms_initialize_all (&all);
2886 fnargs = assign_parms_augmented_arg_list (&all);
2888 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
2890 struct assign_parm_data_one data;
2892 /* Extract the type of PARM; adjust it according to ABI. */
2893 assign_parm_find_data_types (&all, parm, &data);
2895 /* Early out for errors and void parameters. */
2896 if (data.passed_mode == VOIDmode)
2898 SET_DECL_RTL (parm, const0_rtx);
2899 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
2903 if (current_function_stdarg && !TREE_CHAIN (parm))
2904 assign_parms_setup_varargs (&all, &data, false);
2906 /* Find out where the parameter arrives in this function. */
2907 assign_parm_find_entry_rtl (&all, &data);
2909 /* Find out where stack space for this parameter might be. */
2910 if (assign_parm_is_stack_parm (&all, &data))
2912 assign_parm_find_stack_rtl (parm, &data);
2913 assign_parm_adjust_entry_rtl (&data);
2916 /* Record permanently how this parm was passed. */
2917 set_decl_incoming_rtl (parm, data.entry_parm);
2919 /* Update info on where next arg arrives in registers. */
2920 FUNCTION_ARG_ADVANCE (all.args_so_far, data.promoted_mode,
2921 data.passed_type, data.named_arg);
2923 assign_parm_adjust_stack_rtl (&data);
2925 if (assign_parm_setup_block_p (&data))
2926 assign_parm_setup_block (&all, parm, &data);
2927 else if (data.passed_pointer || use_register_for_decl (parm))
2928 assign_parm_setup_reg (&all, parm, &data);
2930 assign_parm_setup_stack (&all, parm, &data);
2933 if (targetm.calls.split_complex_arg && fnargs != all.orig_fnargs)
2934 assign_parms_unsplit_complex (&all, fnargs);
2936 /* Output all parameter conversion instructions (possibly including calls)
2937 now that all parameters have been copied out of hard registers. */
2938 emit_insn (all.conversion_insns);
2940 /* If we are receiving a struct value address as the first argument, set up
2941 the RTL for the function result. As this might require code to convert
2942 the transmitted address to Pmode, we do this here to ensure that possible
2943 preliminary conversions of the address have been emitted already. */
2944 if (all.function_result_decl)
2946 tree result = DECL_RESULT (current_function_decl);
2947 rtx addr = DECL_RTL (all.function_result_decl);
2950 if (DECL_BY_REFERENCE (result))
2954 addr = convert_memory_address (Pmode, addr);
2955 x = gen_rtx_MEM (DECL_MODE (result), addr);
2956 set_mem_attributes (x, result, 1);
2958 SET_DECL_RTL (result, x);
2961 /* We have aligned all the args, so add space for the pretend args. */
2962 current_function_pretend_args_size = all.pretend_args_size;
2963 all.stack_args_size.constant += all.extra_pretend_bytes;
2964 current_function_args_size = all.stack_args_size.constant;
2966 /* Adjust function incoming argument size for alignment and
2969 #ifdef REG_PARM_STACK_SPACE
2970 current_function_args_size = MAX (current_function_args_size,
2971 REG_PARM_STACK_SPACE (fndecl));
2974 current_function_args_size
2975 = ((current_function_args_size + STACK_BYTES - 1)
2976 / STACK_BYTES) * STACK_BYTES;
2978 #ifdef ARGS_GROW_DOWNWARD
2979 current_function_arg_offset_rtx
2980 = (all.stack_args_size.var == 0 ? GEN_INT (-all.stack_args_size.constant)
2981 : expand_expr (size_diffop (all.stack_args_size.var,
2982 size_int (-all.stack_args_size.constant)),
2983 NULL_RTX, VOIDmode, 0));
2985 current_function_arg_offset_rtx = ARGS_SIZE_RTX (all.stack_args_size);
2988 /* See how many bytes, if any, of its args a function should try to pop
2991 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
2992 current_function_args_size);
2994 /* For stdarg.h function, save info about
2995 regs and stack space used by the named args. */
2997 current_function_args_info = all.args_so_far;
2999 /* Set the rtx used for the function return value. Put this in its
3000 own variable so any optimizers that need this information don't have
3001 to include tree.h. Do this here so it gets done when an inlined
3002 function gets output. */
3004 current_function_return_rtx
3005 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
3006 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
3008 /* If scalar return value was computed in a pseudo-reg, or was a named
3009 return value that got dumped to the stack, copy that to the hard
3011 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
3013 tree decl_result = DECL_RESULT (fndecl);
3014 rtx decl_rtl = DECL_RTL (decl_result);
3016 if (REG_P (decl_rtl)
3017 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
3018 : DECL_REGISTER (decl_result))
3022 #ifdef FUNCTION_OUTGOING_VALUE
3023 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
3026 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
3029 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
3030 /* The delay slot scheduler assumes that current_function_return_rtx
3031 holds the hard register containing the return value, not a
3032 temporary pseudo. */
3033 current_function_return_rtx = real_decl_rtl;
3038 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3039 For all seen types, gimplify their sizes. */
3042 gimplify_parm_type (tree *tp, int *walk_subtrees, void *data)
3049 if (POINTER_TYPE_P (t))
3051 else if (TYPE_SIZE (t) && !TREE_CONSTANT (TYPE_SIZE (t))
3052 && !TYPE_SIZES_GIMPLIFIED (t))
3054 gimplify_type_sizes (t, (tree *) data);
3062 /* Gimplify the parameter list for current_function_decl. This involves
3063 evaluating SAVE_EXPRs of variable sized parameters and generating code
3064 to implement callee-copies reference parameters. Returns a list of
3065 statements to add to the beginning of the function, or NULL if nothing
3069 gimplify_parameters (void)
3071 struct assign_parm_data_all all;
3072 tree fnargs, parm, stmts = NULL;
3074 assign_parms_initialize_all (&all);
3075 fnargs = assign_parms_augmented_arg_list (&all);
3077 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
3079 struct assign_parm_data_one data;
3081 /* Extract the type of PARM; adjust it according to ABI. */
3082 assign_parm_find_data_types (&all, parm, &data);
3084 /* Early out for errors and void parameters. */
3085 if (data.passed_mode == VOIDmode || DECL_SIZE (parm) == NULL)
3088 /* Update info on where next arg arrives in registers. */
3089 FUNCTION_ARG_ADVANCE (all.args_so_far, data.promoted_mode,
3090 data.passed_type, data.named_arg);
3092 /* ??? Once upon a time variable_size stuffed parameter list
3093 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3094 turned out to be less than manageable in the gimple world.
3095 Now we have to hunt them down ourselves. */
3096 walk_tree_without_duplicates (&data.passed_type,
3097 gimplify_parm_type, &stmts);
3099 if (!TREE_CONSTANT (DECL_SIZE (parm)))
3101 gimplify_one_sizepos (&DECL_SIZE (parm), &stmts);
3102 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm), &stmts);
3105 if (data.passed_pointer)
3107 tree type = TREE_TYPE (data.passed_type);
3108 if (reference_callee_copied (&all.args_so_far, TYPE_MODE (type),
3109 type, data.named_arg))
3113 /* For constant sized objects, this is trivial; for
3114 variable-sized objects, we have to play games. */
3115 if (TREE_CONSTANT (DECL_SIZE (parm)))
3117 local = create_tmp_var (type, get_name (parm));
3118 DECL_IGNORED_P (local) = 0;
3122 tree ptr_type, addr, args;
3124 ptr_type = build_pointer_type (type);
3125 addr = create_tmp_var (ptr_type, get_name (parm));
3126 DECL_IGNORED_P (addr) = 0;
3127 local = build_fold_indirect_ref (addr);
3129 args = tree_cons (NULL, DECL_SIZE_UNIT (parm), NULL);
3130 t = built_in_decls[BUILT_IN_ALLOCA];
3131 t = build_function_call_expr (t, args);
3132 t = fold_convert (ptr_type, t);
3133 t = build2 (MODIFY_EXPR, void_type_node, addr, t);
3134 gimplify_and_add (t, &stmts);
3137 t = build2 (MODIFY_EXPR, void_type_node, local, parm);
3138 gimplify_and_add (t, &stmts);
3140 DECL_VALUE_EXPR (parm) = local;
3148 /* Indicate whether REGNO is an incoming argument to the current function
3149 that was promoted to a wider mode. If so, return the RTX for the
3150 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
3151 that REGNO is promoted from and whether the promotion was signed or
3155 promoted_input_arg (unsigned int regno, enum machine_mode *pmode, int *punsignedp)
3159 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
3160 arg = TREE_CHAIN (arg))
3161 if (REG_P (DECL_INCOMING_RTL (arg))
3162 && REGNO (DECL_INCOMING_RTL (arg)) == regno
3163 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
3165 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
3166 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (arg));
3168 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
3169 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
3170 && mode != DECL_MODE (arg))
3172 *pmode = DECL_MODE (arg);
3173 *punsignedp = unsignedp;
3174 return DECL_INCOMING_RTL (arg);
3182 /* Compute the size and offset from the start of the stacked arguments for a
3183 parm passed in mode PASSED_MODE and with type TYPE.
3185 INITIAL_OFFSET_PTR points to the current offset into the stacked
3188 The starting offset and size for this parm are returned in
3189 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3190 nonzero, the offset is that of stack slot, which is returned in
3191 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3192 padding required from the initial offset ptr to the stack slot.
3194 IN_REGS is nonzero if the argument will be passed in registers. It will
3195 never be set if REG_PARM_STACK_SPACE is not defined.
3197 FNDECL is the function in which the argument was defined.
3199 There are two types of rounding that are done. The first, controlled by
3200 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
3201 list to be aligned to the specific boundary (in bits). This rounding
3202 affects the initial and starting offsets, but not the argument size.
3204 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3205 optionally rounds the size of the parm to PARM_BOUNDARY. The
3206 initial offset is not affected by this rounding, while the size always
3207 is and the starting offset may be. */
3209 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3210 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3211 callers pass in the total size of args so far as
3212 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
3215 locate_and_pad_parm (enum machine_mode passed_mode, tree type, int in_regs,
3216 int partial, tree fndecl ATTRIBUTE_UNUSED,
3217 struct args_size *initial_offset_ptr,
3218 struct locate_and_pad_arg_data *locate)
3221 enum direction where_pad;
3223 int reg_parm_stack_space = 0;
3224 int part_size_in_regs;
3226 #ifdef REG_PARM_STACK_SPACE
3227 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
3229 /* If we have found a stack parm before we reach the end of the
3230 area reserved for registers, skip that area. */
3233 if (reg_parm_stack_space > 0)
3235 if (initial_offset_ptr->var)
3237 initial_offset_ptr->var
3238 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
3239 ssize_int (reg_parm_stack_space));
3240 initial_offset_ptr->constant = 0;
3242 else if (initial_offset_ptr->constant < reg_parm_stack_space)
3243 initial_offset_ptr->constant = reg_parm_stack_space;
3246 #endif /* REG_PARM_STACK_SPACE */
3248 part_size_in_regs = (reg_parm_stack_space == 0 ? partial : 0);
3251 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
3252 where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
3253 boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
3254 locate->where_pad = where_pad;
3255 locate->boundary = boundary;
3257 #ifdef ARGS_GROW_DOWNWARD
3258 locate->slot_offset.constant = -initial_offset_ptr->constant;
3259 if (initial_offset_ptr->var)
3260 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
3261 initial_offset_ptr->var);
3265 if (where_pad != none
3266 && (!host_integerp (sizetree, 1)
3267 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
3268 s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
3269 SUB_PARM_SIZE (locate->slot_offset, s2);
3272 locate->slot_offset.constant += part_size_in_regs;
3275 #ifdef REG_PARM_STACK_SPACE
3276 || REG_PARM_STACK_SPACE (fndecl) > 0
3279 pad_to_arg_alignment (&locate->slot_offset, boundary,
3280 &locate->alignment_pad);
3282 locate->size.constant = (-initial_offset_ptr->constant
3283 - locate->slot_offset.constant);
3284 if (initial_offset_ptr->var)
3285 locate->size.var = size_binop (MINUS_EXPR,
3286 size_binop (MINUS_EXPR,
3288 initial_offset_ptr->var),
3289 locate->slot_offset.var);
3291 /* Pad_below needs the pre-rounded size to know how much to pad
3293 locate->offset = locate->slot_offset;
3294 if (where_pad == downward)
3295 pad_below (&locate->offset, passed_mode, sizetree);
3297 #else /* !ARGS_GROW_DOWNWARD */
3299 #ifdef REG_PARM_STACK_SPACE
3300 || REG_PARM_STACK_SPACE (fndecl) > 0
3303 pad_to_arg_alignment (initial_offset_ptr, boundary,
3304 &locate->alignment_pad);
3305 locate->slot_offset = *initial_offset_ptr;
3307 #ifdef PUSH_ROUNDING
3308 if (passed_mode != BLKmode)
3309 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
3312 /* Pad_below needs the pre-rounded size to know how much to pad below
3313 so this must be done before rounding up. */
3314 locate->offset = locate->slot_offset;
3315 if (where_pad == downward)
3316 pad_below (&locate->offset, passed_mode, sizetree);
3318 if (where_pad != none
3319 && (!host_integerp (sizetree, 1)
3320 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
3321 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
3323 ADD_PARM_SIZE (locate->size, sizetree);
3325 locate->size.constant -= part_size_in_regs;
3326 #endif /* ARGS_GROW_DOWNWARD */
3329 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
3330 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
3333 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
3334 struct args_size *alignment_pad)
3336 tree save_var = NULL_TREE;
3337 HOST_WIDE_INT save_constant = 0;
3338 int boundary_in_bytes = boundary / BITS_PER_UNIT;
3339 HOST_WIDE_INT sp_offset = STACK_POINTER_OFFSET;
3341 #ifdef SPARC_STACK_BOUNDARY_HACK
3342 /* The sparc port has a bug. It sometimes claims a STACK_BOUNDARY
3343 higher than the real alignment of %sp. However, when it does this,
3344 the alignment of %sp+STACK_POINTER_OFFSET will be STACK_BOUNDARY.
3345 This is a temporary hack while the sparc port is fixed. */
3346 if (SPARC_STACK_BOUNDARY_HACK)
3350 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
3352 save_var = offset_ptr->var;
3353 save_constant = offset_ptr->constant;
3356 alignment_pad->var = NULL_TREE;
3357 alignment_pad->constant = 0;
3359 if (boundary > BITS_PER_UNIT)
3361 if (offset_ptr->var)
3363 tree sp_offset_tree = ssize_int (sp_offset);
3364 tree offset = size_binop (PLUS_EXPR,
3365 ARGS_SIZE_TREE (*offset_ptr),
3367 #ifdef ARGS_GROW_DOWNWARD
3368 tree rounded = round_down (offset, boundary / BITS_PER_UNIT);
3370 tree rounded = round_up (offset, boundary / BITS_PER_UNIT);
3373 offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
3374 /* ARGS_SIZE_TREE includes constant term. */
3375 offset_ptr->constant = 0;
3376 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
3377 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
3382 offset_ptr->constant = -sp_offset +
3383 #ifdef ARGS_GROW_DOWNWARD
3384 FLOOR_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
3386 CEIL_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
3388 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
3389 alignment_pad->constant = offset_ptr->constant - save_constant;
3395 pad_below (struct args_size *offset_ptr, enum machine_mode passed_mode, tree sizetree)
3397 if (passed_mode != BLKmode)
3399 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
3400 offset_ptr->constant
3401 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
3402 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
3403 - GET_MODE_SIZE (passed_mode));
3407 if (TREE_CODE (sizetree) != INTEGER_CST
3408 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
3410 /* Round the size up to multiple of PARM_BOUNDARY bits. */
3411 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
3413 ADD_PARM_SIZE (*offset_ptr, s2);
3414 SUB_PARM_SIZE (*offset_ptr, sizetree);
3419 /* Walk the tree of blocks describing the binding levels within a function
3420 and warn about variables the might be killed by setjmp or vfork.
3421 This is done after calling flow_analysis and before global_alloc
3422 clobbers the pseudo-regs to hard regs. */
3425 setjmp_vars_warning (tree block)
3429 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
3431 if (TREE_CODE (decl) == VAR_DECL
3432 && DECL_RTL_SET_P (decl)
3433 && REG_P (DECL_RTL (decl))
3434 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
3435 warning (0, "%Jvariable %qD might be clobbered by %<longjmp%>"
3440 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
3441 setjmp_vars_warning (sub);
3444 /* Do the appropriate part of setjmp_vars_warning
3445 but for arguments instead of local variables. */
3448 setjmp_args_warning (void)
3451 for (decl = DECL_ARGUMENTS (current_function_decl);
3452 decl; decl = TREE_CHAIN (decl))
3453 if (DECL_RTL (decl) != 0
3454 && REG_P (DECL_RTL (decl))
3455 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
3456 warning (0, "%Jargument %qD might be clobbered by %<longjmp%> or %<vfork%>",
3461 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
3462 and create duplicate blocks. */
3463 /* ??? Need an option to either create block fragments or to create
3464 abstract origin duplicates of a source block. It really depends
3465 on what optimization has been performed. */
3468 reorder_blocks (void)
3470 tree block = DECL_INITIAL (current_function_decl);
3471 VEC(tree,heap) *block_stack;
3473 if (block == NULL_TREE)
3476 block_stack = VEC_alloc (tree, heap, 10);
3478 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
3479 clear_block_marks (block);
3481 /* Prune the old trees away, so that they don't get in the way. */
3482 BLOCK_SUBBLOCKS (block) = NULL_TREE;
3483 BLOCK_CHAIN (block) = NULL_TREE;
3485 /* Recreate the block tree from the note nesting. */
3486 reorder_blocks_1 (get_insns (), block, &block_stack);
3487 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
3489 /* Remove deleted blocks from the block fragment chains. */
3490 reorder_fix_fragments (block);
3492 VEC_free (tree, heap, block_stack);
3495 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
3498 clear_block_marks (tree block)
3502 TREE_ASM_WRITTEN (block) = 0;
3503 clear_block_marks (BLOCK_SUBBLOCKS (block));
3504 block = BLOCK_CHAIN (block);
3509 reorder_blocks_1 (rtx insns, tree current_block, VEC(tree,heap) **p_block_stack)
3513 for (insn = insns; insn; insn = NEXT_INSN (insn))
3517 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
3519 tree block = NOTE_BLOCK (insn);
3521 /* If we have seen this block before, that means it now
3522 spans multiple address regions. Create a new fragment. */
3523 if (TREE_ASM_WRITTEN (block))
3525 tree new_block = copy_node (block);
3528 origin = (BLOCK_FRAGMENT_ORIGIN (block)
3529 ? BLOCK_FRAGMENT_ORIGIN (block)
3531 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
3532 BLOCK_FRAGMENT_CHAIN (new_block)
3533 = BLOCK_FRAGMENT_CHAIN (origin);
3534 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
3536 NOTE_BLOCK (insn) = new_block;
3540 BLOCK_SUBBLOCKS (block) = 0;
3541 TREE_ASM_WRITTEN (block) = 1;
3542 /* When there's only one block for the entire function,
3543 current_block == block and we mustn't do this, it
3544 will cause infinite recursion. */
3545 if (block != current_block)
3547 BLOCK_SUPERCONTEXT (block) = current_block;
3548 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
3549 BLOCK_SUBBLOCKS (current_block) = block;
3550 current_block = block;
3552 VEC_safe_push (tree, heap, *p_block_stack, block);
3554 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
3556 NOTE_BLOCK (insn) = VEC_pop (tree, *p_block_stack);
3557 BLOCK_SUBBLOCKS (current_block)
3558 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
3559 current_block = BLOCK_SUPERCONTEXT (current_block);
3565 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
3566 appears in the block tree, select one of the fragments to become
3567 the new origin block. */
3570 reorder_fix_fragments (tree block)
3574 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
3575 tree new_origin = NULL_TREE;
3579 if (! TREE_ASM_WRITTEN (dup_origin))
3581 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
3583 /* Find the first of the remaining fragments. There must
3584 be at least one -- the current block. */
3585 while (! TREE_ASM_WRITTEN (new_origin))
3586 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
3587 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
3590 else if (! dup_origin)
3593 /* Re-root the rest of the fragments to the new origin. In the
3594 case that DUP_ORIGIN was null, that means BLOCK was the origin
3595 of a chain of fragments and we want to remove those fragments
3596 that didn't make it to the output. */
3599 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
3604 if (TREE_ASM_WRITTEN (chain))
3606 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
3608 pp = &BLOCK_FRAGMENT_CHAIN (chain);
3610 chain = BLOCK_FRAGMENT_CHAIN (chain);
3615 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
3616 block = BLOCK_CHAIN (block);
3620 /* Reverse the order of elements in the chain T of blocks,
3621 and return the new head of the chain (old last element). */
3624 blocks_nreverse (tree t)
3626 tree prev = 0, decl, next;
3627 for (decl = t; decl; decl = next)
3629 next = BLOCK_CHAIN (decl);
3630 BLOCK_CHAIN (decl) = prev;
3636 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
3637 non-NULL, list them all into VECTOR, in a depth-first preorder
3638 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
3642 all_blocks (tree block, tree *vector)
3648 TREE_ASM_WRITTEN (block) = 0;
3650 /* Record this block. */
3652 vector[n_blocks] = block;
3656 /* Record the subblocks, and their subblocks... */
3657 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
3658 vector ? vector + n_blocks : 0);
3659 block = BLOCK_CHAIN (block);
3665 /* Return a vector containing all the blocks rooted at BLOCK. The
3666 number of elements in the vector is stored in N_BLOCKS_P. The
3667 vector is dynamically allocated; it is the caller's responsibility
3668 to call `free' on the pointer returned. */
3671 get_block_vector (tree block, int *n_blocks_p)
3675 *n_blocks_p = all_blocks (block, NULL);
3676 block_vector = xmalloc (*n_blocks_p * sizeof (tree));
3677 all_blocks (block, block_vector);
3679 return block_vector;
3682 static GTY(()) int next_block_index = 2;
3684 /* Set BLOCK_NUMBER for all the blocks in FN. */
3687 number_blocks (tree fn)
3693 /* For SDB and XCOFF debugging output, we start numbering the blocks
3694 from 1 within each function, rather than keeping a running
3696 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
3697 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
3698 next_block_index = 1;
3701 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
3703 /* The top-level BLOCK isn't numbered at all. */
3704 for (i = 1; i < n_blocks; ++i)
3705 /* We number the blocks from two. */
3706 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
3708 free (block_vector);
3713 /* If VAR is present in a subblock of BLOCK, return the subblock. */
3716 debug_find_var_in_block_tree (tree var, tree block)
3720 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
3724 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
3726 tree ret = debug_find_var_in_block_tree (var, t);
3734 /* Allocate a function structure for FNDECL and set its contents
3738 allocate_struct_function (tree fndecl)
3741 tree fntype = fndecl ? TREE_TYPE (fndecl) : NULL_TREE;
3743 cfun = ggc_alloc_cleared (sizeof (struct function));
3744 cfun->cfg = ggc_alloc_cleared (sizeof (struct control_flow_graph));
3748 cfun->stack_alignment_needed = STACK_BOUNDARY;
3749 cfun->preferred_stack_boundary = STACK_BOUNDARY;
3751 current_function_funcdef_no = funcdef_no++;
3753 cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL;
3755 init_eh_for_function ();
3757 lang_hooks.function.init (cfun);
3758 if (init_machine_status)
3759 cfun->machine = (*init_machine_status) ();
3764 DECL_STRUCT_FUNCTION (fndecl) = cfun;
3765 cfun->decl = fndecl;
3767 result = DECL_RESULT (fndecl);
3768 if (aggregate_value_p (result, fndecl))
3770 #ifdef PCC_STATIC_STRUCT_RETURN
3771 current_function_returns_pcc_struct = 1;
3773 current_function_returns_struct = 1;
3776 current_function_returns_pointer = POINTER_TYPE_P (TREE_TYPE (result));
3778 current_function_stdarg
3780 && TYPE_ARG_TYPES (fntype) != 0
3781 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
3782 != void_type_node));
3784 /* Assume all registers in stdarg functions need to be saved. */
3785 cfun->va_list_gpr_size = VA_LIST_MAX_GPR_SIZE;
3786 cfun->va_list_fpr_size = VA_LIST_MAX_FPR_SIZE;
3789 /* Reset cfun, and other non-struct-function variables to defaults as
3790 appropriate for emitting rtl at the start of a function. */
3793 prepare_function_start (tree fndecl)
3795 if (fndecl && DECL_STRUCT_FUNCTION (fndecl))
3796 cfun = DECL_STRUCT_FUNCTION (fndecl);
3798 allocate_struct_function (fndecl);
3800 init_varasm_status (cfun);
3803 cse_not_expected = ! optimize;
3805 /* Caller save not needed yet. */
3806 caller_save_needed = 0;
3808 /* We haven't done register allocation yet. */
3811 /* Indicate that we have not instantiated virtual registers yet. */
3812 virtuals_instantiated = 0;
3814 /* Indicate that we want CONCATs now. */
3815 generating_concat_p = 1;
3817 /* Indicate we have no need of a frame pointer yet. */
3818 frame_pointer_needed = 0;
3821 /* Initialize the rtl expansion mechanism so that we can do simple things
3822 like generate sequences. This is used to provide a context during global
3823 initialization of some passes. */
3825 init_dummy_function_start (void)
3827 prepare_function_start (NULL);
3830 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
3831 and initialize static variables for generating RTL for the statements
3835 init_function_start (tree subr)
3837 prepare_function_start (subr);
3839 /* Prevent ever trying to delete the first instruction of a
3840 function. Also tell final how to output a linenum before the
3841 function prologue. Note linenums could be missing, e.g. when
3842 compiling a Java .class file. */
3843 if (! DECL_IS_BUILTIN (subr))
3844 emit_line_note (DECL_SOURCE_LOCATION (subr));
3846 /* Make sure first insn is a note even if we don't want linenums.
3847 This makes sure the first insn will never be deleted.
3848 Also, final expects a note to appear there. */
3849 emit_note (NOTE_INSN_DELETED);
3851 /* Warn if this value is an aggregate type,
3852 regardless of which calling convention we are using for it. */
3853 if (warn_aggregate_return
3854 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
3855 warning (0, "function returns an aggregate");
3858 /* Make sure all values used by the optimization passes have sane
3861 init_function_for_compilation (void)
3865 /* No prologue/epilogue insns yet. */
3866 VARRAY_GROW (prologue, 0);
3867 VARRAY_GROW (epilogue, 0);
3868 VARRAY_GROW (sibcall_epilogue, 0);
3872 expand_main_function (void)
3874 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
3875 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
3877 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
3881 /* Forcibly align the stack. */
3882 #ifdef STACK_GROWS_DOWNWARD
3883 tmp = expand_simple_binop (Pmode, AND, stack_pointer_rtx, GEN_INT(-align),
3884 stack_pointer_rtx, 1, OPTAB_WIDEN);
3886 tmp = expand_simple_binop (Pmode, PLUS, stack_pointer_rtx,
3887 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
3888 tmp = expand_simple_binop (Pmode, AND, tmp, GEN_INT (-align),
3889 stack_pointer_rtx, 1, OPTAB_WIDEN);
3891 if (tmp != stack_pointer_rtx)
3892 emit_move_insn (stack_pointer_rtx, tmp);
3894 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
3895 tmp = force_reg (Pmode, const0_rtx);
3896 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
3900 for (tmp = get_last_insn (); tmp; tmp = PREV_INSN (tmp))
3901 if (NOTE_P (tmp) && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_FUNCTION_BEG)
3904 emit_insn_before (seq, tmp);
3910 #if (defined(INVOKE__main) \
3911 || (!defined(HAS_INIT_SECTION) \
3912 && !defined(INIT_SECTION_ASM_OP) \
3913 && !defined(INIT_ARRAY_SECTION_ASM_OP)))
3914 emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0);
3918 /* Start the RTL for a new function, and set variables used for
3920 SUBR is the FUNCTION_DECL node.
3921 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
3922 the function's parameters, which must be run at any return statement. */
3925 expand_function_start (tree subr)
3927 /* Make sure volatile mem refs aren't considered
3928 valid operands of arithmetic insns. */
3929 init_recog_no_volatile ();
3931 current_function_profile
3933 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
3935 current_function_limit_stack
3936 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
3938 /* Make the label for return statements to jump to. Do not special
3939 case machines with special return instructions -- they will be
3940 handled later during jump, ifcvt, or epilogue creation. */
3941 return_label = gen_label_rtx ();
3943 /* Initialize rtx used to return the value. */
3944 /* Do this before assign_parms so that we copy the struct value address
3945 before any library calls that assign parms might generate. */
3947 /* Decide whether to return the value in memory or in a register. */
3948 if (aggregate_value_p (DECL_RESULT (subr), subr))
3950 /* Returning something that won't go in a register. */
3951 rtx value_address = 0;
3953 #ifdef PCC_STATIC_STRUCT_RETURN
3954 if (current_function_returns_pcc_struct)
3956 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
3957 value_address = assemble_static_space (size);
3962 rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 1);
3963 /* Expect to be passed the address of a place to store the value.
3964 If it is passed as an argument, assign_parms will take care of
3968 value_address = gen_reg_rtx (Pmode);
3969 emit_move_insn (value_address, sv);
3974 rtx x = value_address;
3975 if (!DECL_BY_REFERENCE (DECL_RESULT (subr)))
3977 x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), x);
3978 set_mem_attributes (x, DECL_RESULT (subr), 1);
3980 SET_DECL_RTL (DECL_RESULT (subr), x);
3983 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
3984 /* If return mode is void, this decl rtl should not be used. */
3985 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
3988 /* Compute the return values into a pseudo reg, which we will copy
3989 into the true return register after the cleanups are done. */
3990 tree return_type = TREE_TYPE (DECL_RESULT (subr));
3991 if (TYPE_MODE (return_type) != BLKmode
3992 && targetm.calls.return_in_msb (return_type))
3993 /* expand_function_end will insert the appropriate padding in
3994 this case. Use the return value's natural (unpadded) mode
3995 within the function proper. */
3996 SET_DECL_RTL (DECL_RESULT (subr),
3997 gen_reg_rtx (TYPE_MODE (return_type)));
4000 /* In order to figure out what mode to use for the pseudo, we
4001 figure out what the mode of the eventual return register will
4002 actually be, and use that. */
4003 rtx hard_reg = hard_function_value (return_type, subr, 1);
4005 /* Structures that are returned in registers are not
4006 aggregate_value_p, so we may see a PARALLEL or a REG. */
4007 if (REG_P (hard_reg))
4008 SET_DECL_RTL (DECL_RESULT (subr),
4009 gen_reg_rtx (GET_MODE (hard_reg)));
4012 gcc_assert (GET_CODE (hard_reg) == PARALLEL);
4013 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
4017 /* Set DECL_REGISTER flag so that expand_function_end will copy the
4018 result to the real return register(s). */
4019 DECL_REGISTER (DECL_RESULT (subr)) = 1;
4022 /* Initialize rtx for parameters and local variables.
4023 In some cases this requires emitting insns. */
4024 assign_parms (subr);
4026 /* If function gets a static chain arg, store it. */
4027 if (cfun->static_chain_decl)
4029 tree parm = cfun->static_chain_decl;
4030 rtx local = gen_reg_rtx (Pmode);
4032 set_decl_incoming_rtl (parm, static_chain_incoming_rtx);
4033 SET_DECL_RTL (parm, local);
4034 mark_reg_pointer (local, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
4036 emit_move_insn (local, static_chain_incoming_rtx);
4039 /* If the function receives a non-local goto, then store the
4040 bits we need to restore the frame pointer. */
4041 if (cfun->nonlocal_goto_save_area)
4046 /* ??? We need to do this save early. Unfortunately here is
4047 before the frame variable gets declared. Help out... */
4048 expand_var (TREE_OPERAND (cfun->nonlocal_goto_save_area, 0));
4050 t_save = build4 (ARRAY_REF, ptr_type_node,
4051 cfun->nonlocal_goto_save_area,
4052 integer_zero_node, NULL_TREE, NULL_TREE);
4053 r_save = expand_expr (t_save, NULL_RTX, VOIDmode, EXPAND_WRITE);
4054 r_save = convert_memory_address (Pmode, r_save);
4056 emit_move_insn (r_save, virtual_stack_vars_rtx);
4057 update_nonlocal_goto_save_area ();
4060 /* The following was moved from init_function_start.
4061 The move is supposed to make sdb output more accurate. */
4062 /* Indicate the beginning of the function body,
4063 as opposed to parm setup. */
4064 emit_note (NOTE_INSN_FUNCTION_BEG);
4066 if (!NOTE_P (get_last_insn ()))
4067 emit_note (NOTE_INSN_DELETED);
4068 parm_birth_insn = get_last_insn ();
4070 if (current_function_profile)
4073 PROFILE_HOOK (current_function_funcdef_no);
4077 /* After the display initializations is where the tail-recursion label
4078 should go, if we end up needing one. Ensure we have a NOTE here
4079 since some things (like trampolines) get placed before this. */
4080 tail_recursion_reentry = emit_note (NOTE_INSN_DELETED);
4082 /* Make sure there is a line number after the function entry setup code. */
4083 force_next_line_note ();
4086 /* Undo the effects of init_dummy_function_start. */
4088 expand_dummy_function_end (void)
4090 /* End any sequences that failed to be closed due to syntax errors. */
4091 while (in_sequence_p ())
4094 /* Outside function body, can't compute type's actual size
4095 until next function's body starts. */
4097 free_after_parsing (cfun);
4098 free_after_compilation (cfun);
4102 /* Call DOIT for each hard register used as a return value from
4103 the current function. */
4106 diddle_return_value (void (*doit) (rtx, void *), void *arg)
4108 rtx outgoing = current_function_return_rtx;
4113 if (REG_P (outgoing))
4114 (*doit) (outgoing, arg);
4115 else if (GET_CODE (outgoing) == PARALLEL)
4119 for (i = 0; i < XVECLEN (outgoing, 0); i++)
4121 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
4123 if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER)
4130 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
4132 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
4136 clobber_return_register (void)
4138 diddle_return_value (do_clobber_return_reg, NULL);
4140 /* In case we do use pseudo to return value, clobber it too. */
4141 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
4143 tree decl_result = DECL_RESULT (current_function_decl);
4144 rtx decl_rtl = DECL_RTL (decl_result);
4145 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
4147 do_clobber_return_reg (decl_rtl, NULL);
4153 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
4155 emit_insn (gen_rtx_USE (VOIDmode, reg));
4159 use_return_register (void)
4161 diddle_return_value (do_use_return_reg, NULL);
4164 /* Possibly warn about unused parameters. */
4166 do_warn_unused_parameter (tree fn)
4170 for (decl = DECL_ARGUMENTS (fn);
4171 decl; decl = TREE_CHAIN (decl))
4172 if (!TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
4173 && DECL_NAME (decl) && !DECL_ARTIFICIAL (decl))
4174 warning (0, "%Junused parameter %qD", decl, decl);
4177 static GTY(()) rtx initial_trampoline;
4179 /* Generate RTL for the end of the current function. */
4182 expand_function_end (void)
4186 /* If arg_pointer_save_area was referenced only from a nested
4187 function, we will not have initialized it yet. Do that now. */
4188 if (arg_pointer_save_area && ! cfun->arg_pointer_save_area_init)
4189 get_arg_pointer_save_area (cfun);
4191 /* If we are doing stack checking and this function makes calls,
4192 do a stack probe at the start of the function to ensure we have enough
4193 space for another stack frame. */
4194 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
4198 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4202 probe_stack_range (STACK_CHECK_PROTECT,
4203 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
4206 emit_insn_before (seq, tail_recursion_reentry);
4211 /* Possibly warn about unused parameters.
4212 When frontend does unit-at-a-time, the warning is already
4213 issued at finalization time. */
4214 if (warn_unused_parameter
4215 && !lang_hooks.callgraph.expand_function)
4216 do_warn_unused_parameter (current_function_decl);
4218 /* End any sequences that failed to be closed due to syntax errors. */
4219 while (in_sequence_p ())
4222 clear_pending_stack_adjust ();
4223 do_pending_stack_adjust ();
4225 /* @@@ This is a kludge. We want to ensure that instructions that
4226 may trap are not moved into the epilogue by scheduling, because
4227 we don't always emit unwind information for the epilogue.
4228 However, not all machine descriptions define a blockage insn, so
4229 emit an ASM_INPUT to act as one. */
4230 if (flag_non_call_exceptions)
4231 emit_insn (gen_rtx_ASM_INPUT (VOIDmode, ""));
4233 /* Mark the end of the function body.
4234 If control reaches this insn, the function can drop through
4235 without returning a value. */
4236 emit_note (NOTE_INSN_FUNCTION_END);
4238 /* Must mark the last line number note in the function, so that the test
4239 coverage code can avoid counting the last line twice. This just tells
4240 the code to ignore the immediately following line note, since there
4241 already exists a copy of this note somewhere above. This line number
4242 note is still needed for debugging though, so we can't delete it. */
4243 if (flag_test_coverage)
4244 emit_note (NOTE_INSN_REPEATED_LINE_NUMBER);
4246 /* Output a linenumber for the end of the function.
4247 SDB depends on this. */
4248 force_next_line_note ();
4249 emit_line_note (input_location);
4251 /* Before the return label (if any), clobber the return
4252 registers so that they are not propagated live to the rest of
4253 the function. This can only happen with functions that drop
4254 through; if there had been a return statement, there would
4255 have either been a return rtx, or a jump to the return label.
4257 We delay actual code generation after the current_function_value_rtx
4259 clobber_after = get_last_insn ();
4261 /* Output the label for the actual return from the function. */
4262 emit_label (return_label);
4264 /* Let except.c know where it should emit the call to unregister
4265 the function context for sjlj exceptions. */
4266 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
4267 sjlj_emit_function_exit_after (get_last_insn ());
4269 /* If scalar return value was computed in a pseudo-reg, or was a named
4270 return value that got dumped to the stack, copy that to the hard
4272 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
4274 tree decl_result = DECL_RESULT (current_function_decl);
4275 rtx decl_rtl = DECL_RTL (decl_result);
4277 if (REG_P (decl_rtl)
4278 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
4279 : DECL_REGISTER (decl_result))
4281 rtx real_decl_rtl = current_function_return_rtx;
4283 /* This should be set in assign_parms. */
4284 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl));
4286 /* If this is a BLKmode structure being returned in registers,
4287 then use the mode computed in expand_return. Note that if
4288 decl_rtl is memory, then its mode may have been changed,
4289 but that current_function_return_rtx has not. */
4290 if (GET_MODE (real_decl_rtl) == BLKmode)
4291 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
4293 /* If a non-BLKmode return value should be padded at the least
4294 significant end of the register, shift it left by the appropriate
4295 amount. BLKmode results are handled using the group load/store
4297 if (TYPE_MODE (TREE_TYPE (decl_result)) != BLKmode
4298 && targetm.calls.return_in_msb (TREE_TYPE (decl_result)))
4300 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl),
4301 REGNO (real_decl_rtl)),
4303 shift_return_value (GET_MODE (decl_rtl), true, real_decl_rtl);
4305 /* If a named return value dumped decl_return to memory, then
4306 we may need to re-do the PROMOTE_MODE signed/unsigned
4308 else if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
4310 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (decl_result));
4312 if (targetm.calls.promote_function_return (TREE_TYPE (current_function_decl)))
4313 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
4316 convert_move (real_decl_rtl, decl_rtl, unsignedp);
4318 else if (GET_CODE (real_decl_rtl) == PARALLEL)
4320 /* If expand_function_start has created a PARALLEL for decl_rtl,
4321 move the result to the real return registers. Otherwise, do
4322 a group load from decl_rtl for a named return. */
4323 if (GET_CODE (decl_rtl) == PARALLEL)
4324 emit_group_move (real_decl_rtl, decl_rtl);
4326 emit_group_load (real_decl_rtl, decl_rtl,
4327 TREE_TYPE (decl_result),
4328 int_size_in_bytes (TREE_TYPE (decl_result)));
4331 emit_move_insn (real_decl_rtl, decl_rtl);
4335 /* If returning a structure, arrange to return the address of the value
4336 in a place where debuggers expect to find it.
4338 If returning a structure PCC style,
4339 the caller also depends on this value.
4340 And current_function_returns_pcc_struct is not necessarily set. */
4341 if (current_function_returns_struct
4342 || current_function_returns_pcc_struct)
4344 rtx value_address = DECL_RTL (DECL_RESULT (current_function_decl));
4345 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
4348 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))
4349 type = TREE_TYPE (type);
4351 value_address = XEXP (value_address, 0);
4353 #ifdef FUNCTION_OUTGOING_VALUE
4354 outgoing = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
4355 current_function_decl);
4357 outgoing = FUNCTION_VALUE (build_pointer_type (type),
4358 current_function_decl);
4361 /* Mark this as a function return value so integrate will delete the
4362 assignment and USE below when inlining this function. */
4363 REG_FUNCTION_VALUE_P (outgoing) = 1;
4365 /* The address may be ptr_mode and OUTGOING may be Pmode. */
4366 value_address = convert_memory_address (GET_MODE (outgoing),
4369 emit_move_insn (outgoing, value_address);
4371 /* Show return register used to hold result (in this case the address
4373 current_function_return_rtx = outgoing;
4376 /* If this is an implementation of throw, do what's necessary to
4377 communicate between __builtin_eh_return and the epilogue. */
4378 expand_eh_return ();
4380 /* Emit the actual code to clobber return register. */
4385 clobber_return_register ();
4386 expand_naked_return ();
4390 emit_insn_after (seq, clobber_after);
4393 /* Output the label for the naked return from the function. */
4394 emit_label (naked_return_label);
4396 /* If we had calls to alloca, and this machine needs
4397 an accurate stack pointer to exit the function,
4398 insert some code to save and restore the stack pointer. */
4399 if (! EXIT_IGNORE_STACK
4400 && current_function_calls_alloca)
4404 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
4405 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
4408 /* ??? This should no longer be necessary since stupid is no longer with
4409 us, but there are some parts of the compiler (eg reload_combine, and
4410 sh mach_dep_reorg) that still try and compute their own lifetime info
4411 instead of using the general framework. */
4412 use_return_register ();
4416 get_arg_pointer_save_area (struct function *f)
4418 rtx ret = f->x_arg_pointer_save_area;
4422 ret = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, f);
4423 f->x_arg_pointer_save_area = ret;
4426 if (f == cfun && ! f->arg_pointer_save_area_init)
4430 /* Save the arg pointer at the beginning of the function. The
4431 generated stack slot may not be a valid memory address, so we
4432 have to check it and fix it if necessary. */
4434 emit_move_insn (validize_mem (ret), virtual_incoming_args_rtx);
4438 push_topmost_sequence ();
4439 emit_insn_after (seq, entry_of_function ());
4440 pop_topmost_sequence ();
4446 /* Extend a vector that records the INSN_UIDs of INSNS
4447 (a list of one or more insns). */
4450 record_insns (rtx insns, varray_type *vecp)
4457 while (tmp != NULL_RTX)
4460 tmp = NEXT_INSN (tmp);
4463 i = VARRAY_SIZE (*vecp);
4464 VARRAY_GROW (*vecp, i + len);
4466 while (tmp != NULL_RTX)
4468 VARRAY_INT (*vecp, i) = INSN_UID (tmp);
4470 tmp = NEXT_INSN (tmp);
4474 /* Set the locator of the insn chain starting at INSN to LOC. */
4476 set_insn_locators (rtx insn, int loc)
4478 while (insn != NULL_RTX)
4481 INSN_LOCATOR (insn) = loc;
4482 insn = NEXT_INSN (insn);
4486 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
4487 be running after reorg, SEQUENCE rtl is possible. */
4490 contains (rtx insn, varray_type vec)
4494 if (NONJUMP_INSN_P (insn)
4495 && GET_CODE (PATTERN (insn)) == SEQUENCE)
4498 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
4499 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
4500 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
4506 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
4507 if (INSN_UID (insn) == VARRAY_INT (vec, j))
4514 prologue_epilogue_contains (rtx insn)
4516 if (contains (insn, prologue))
4518 if (contains (insn, epilogue))
4524 sibcall_epilogue_contains (rtx insn)
4526 if (sibcall_epilogue)
4527 return contains (insn, sibcall_epilogue);
4532 /* Insert gen_return at the end of block BB. This also means updating
4533 block_for_insn appropriately. */
4536 emit_return_into_block (basic_block bb, rtx line_note)
4538 emit_jump_insn_after (gen_return (), BB_END (bb));
4540 emit_note_copy_after (line_note, PREV_INSN (BB_END (bb)));
4542 #endif /* HAVE_return */
4544 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
4546 /* These functions convert the epilogue into a variant that does not
4547 modify the stack pointer. This is used in cases where a function
4548 returns an object whose size is not known until it is computed.
4549 The called function leaves the object on the stack, leaves the
4550 stack depressed, and returns a pointer to the object.
4552 What we need to do is track all modifications and references to the
4553 stack pointer, deleting the modifications and changing the
4554 references to point to the location the stack pointer would have
4555 pointed to had the modifications taken place.
4557 These functions need to be portable so we need to make as few
4558 assumptions about the epilogue as we can. However, the epilogue
4559 basically contains three things: instructions to reset the stack
4560 pointer, instructions to reload registers, possibly including the
4561 frame pointer, and an instruction to return to the caller.
4563 We must be sure of what a relevant epilogue insn is doing. We also
4564 make no attempt to validate the insns we make since if they are
4565 invalid, we probably can't do anything valid. The intent is that
4566 these routines get "smarter" as more and more machines start to use
4567 them and they try operating on different epilogues.
4569 We use the following structure to track what the part of the
4570 epilogue that we've already processed has done. We keep two copies
4571 of the SP equivalence, one for use during the insn we are
4572 processing and one for use in the next insn. The difference is
4573 because one part of a PARALLEL may adjust SP and the other may use
4578 rtx sp_equiv_reg; /* REG that SP is set from, perhaps SP. */
4579 HOST_WIDE_INT sp_offset; /* Offset from SP_EQUIV_REG of present SP. */
4580 rtx new_sp_equiv_reg; /* REG to be used at end of insn. */
4581 HOST_WIDE_INT new_sp_offset; /* Offset to be used at end of insn. */
4582 rtx equiv_reg_src; /* If nonzero, the value that SP_EQUIV_REG
4583 should be set to once we no longer need
4585 rtx const_equiv[FIRST_PSEUDO_REGISTER]; /* Any known constant equivalences
4589 static void handle_epilogue_set (rtx, struct epi_info *);
4590 static void update_epilogue_consts (rtx, rtx, void *);
4591 static void emit_equiv_load (struct epi_info *);
4593 /* Modify INSN, a list of one or more insns that is part of the epilogue, to
4594 no modifications to the stack pointer. Return the new list of insns. */
4597 keep_stack_depressed (rtx insns)
4600 struct epi_info info;
4603 /* If the epilogue is just a single instruction, it must be OK as is. */
4604 if (NEXT_INSN (insns) == NULL_RTX)
4607 /* Otherwise, start a sequence, initialize the information we have, and
4608 process all the insns we were given. */
4611 info.sp_equiv_reg = stack_pointer_rtx;
4613 info.equiv_reg_src = 0;
4615 for (j = 0; j < FIRST_PSEUDO_REGISTER; j++)
4616 info.const_equiv[j] = 0;
4620 while (insn != NULL_RTX)
4622 next = NEXT_INSN (insn);
4631 /* If this insn references the register that SP is equivalent to and
4632 we have a pending load to that register, we must force out the load
4633 first and then indicate we no longer know what SP's equivalent is. */
4634 if (info.equiv_reg_src != 0
4635 && reg_referenced_p (info.sp_equiv_reg, PATTERN (insn)))
4637 emit_equiv_load (&info);
4638 info.sp_equiv_reg = 0;
4641 info.new_sp_equiv_reg = info.sp_equiv_reg;
4642 info.new_sp_offset = info.sp_offset;
4644 /* If this is a (RETURN) and the return address is on the stack,
4645 update the address and change to an indirect jump. */
4646 if (GET_CODE (PATTERN (insn)) == RETURN
4647 || (GET_CODE (PATTERN (insn)) == PARALLEL
4648 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == RETURN))
4650 rtx retaddr = INCOMING_RETURN_ADDR_RTX;
4652 HOST_WIDE_INT offset = 0;
4653 rtx jump_insn, jump_set;
4655 /* If the return address is in a register, we can emit the insn
4656 unchanged. Otherwise, it must be a MEM and we see what the
4657 base register and offset are. In any case, we have to emit any
4658 pending load to the equivalent reg of SP, if any. */
4659 if (REG_P (retaddr))
4661 emit_equiv_load (&info);
4669 gcc_assert (MEM_P (retaddr));
4671 ret_ptr = XEXP (retaddr, 0);
4673 if (REG_P (ret_ptr))
4675 base = gen_rtx_REG (Pmode, REGNO (ret_ptr));
4680 gcc_assert (GET_CODE (ret_ptr) == PLUS
4681 && REG_P (XEXP (ret_ptr, 0))
4682 && GET_CODE (XEXP (ret_ptr, 1)) == CONST_INT);
4683 base = gen_rtx_REG (Pmode, REGNO (XEXP (ret_ptr, 0)));
4684 offset = INTVAL (XEXP (ret_ptr, 1));
4688 /* If the base of the location containing the return pointer
4689 is SP, we must update it with the replacement address. Otherwise,
4690 just build the necessary MEM. */
4691 retaddr = plus_constant (base, offset);
4692 if (base == stack_pointer_rtx)
4693 retaddr = simplify_replace_rtx (retaddr, stack_pointer_rtx,
4694 plus_constant (info.sp_equiv_reg,
4697 retaddr = gen_rtx_MEM (Pmode, retaddr);
4699 /* If there is a pending load to the equivalent register for SP
4700 and we reference that register, we must load our address into
4701 a scratch register and then do that load. */
4702 if (info.equiv_reg_src
4703 && reg_overlap_mentioned_p (info.equiv_reg_src, retaddr))
4708 for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
4709 if (HARD_REGNO_MODE_OK (regno, Pmode)
4710 && !fixed_regs[regno]
4711 && TEST_HARD_REG_BIT (regs_invalidated_by_call, regno)
4712 && !REGNO_REG_SET_P (EXIT_BLOCK_PTR->global_live_at_start,
4714 && !refers_to_regno_p (regno,
4715 regno + hard_regno_nregs[regno]
4717 info.equiv_reg_src, NULL)
4718 && info.const_equiv[regno] == 0)
4721 gcc_assert (regno < FIRST_PSEUDO_REGISTER);
4723 reg = gen_rtx_REG (Pmode, regno);
4724 emit_move_insn (reg, retaddr);
4728 emit_equiv_load (&info);
4729 jump_insn = emit_jump_insn (gen_indirect_jump (retaddr));
4731 /* Show the SET in the above insn is a RETURN. */
4732 jump_set = single_set (jump_insn);
4733 gcc_assert (jump_set);
4734 SET_IS_RETURN_P (jump_set) = 1;
4737 /* If SP is not mentioned in the pattern and its equivalent register, if
4738 any, is not modified, just emit it. Otherwise, if neither is set,
4739 replace the reference to SP and emit the insn. If none of those are
4740 true, handle each SET individually. */
4741 else if (!reg_mentioned_p (stack_pointer_rtx, PATTERN (insn))
4742 && (info.sp_equiv_reg == stack_pointer_rtx
4743 || !reg_set_p (info.sp_equiv_reg, insn)))
4745 else if (! reg_set_p (stack_pointer_rtx, insn)
4746 && (info.sp_equiv_reg == stack_pointer_rtx
4747 || !reg_set_p (info.sp_equiv_reg, insn)))
4751 changed = validate_replace_rtx (stack_pointer_rtx,
4752 plus_constant (info.sp_equiv_reg,
4755 gcc_assert (changed);
4759 else if (GET_CODE (PATTERN (insn)) == SET)
4760 handle_epilogue_set (PATTERN (insn), &info);
4761 else if (GET_CODE (PATTERN (insn)) == PARALLEL)
4763 for (j = 0; j < XVECLEN (PATTERN (insn), 0); j++)
4764 if (GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET)
4765 handle_epilogue_set (XVECEXP (PATTERN (insn), 0, j), &info);
4770 info.sp_equiv_reg = info.new_sp_equiv_reg;
4771 info.sp_offset = info.new_sp_offset;
4773 /* Now update any constants this insn sets. */
4774 note_stores (PATTERN (insn), update_epilogue_consts, &info);
4778 insns = get_insns ();
4783 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
4784 structure that contains information about what we've seen so far. We
4785 process this SET by either updating that data or by emitting one or
4789 handle_epilogue_set (rtx set, struct epi_info *p)
4791 /* First handle the case where we are setting SP. Record what it is being
4792 set from, which we must be able to determine */
4793 if (reg_set_p (stack_pointer_rtx, set))
4795 gcc_assert (SET_DEST (set) == stack_pointer_rtx);
4797 if (GET_CODE (SET_SRC (set)) == PLUS)
4799 p->new_sp_equiv_reg = XEXP (SET_SRC (set), 0);
4800 if (GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT)
4801 p->new_sp_offset = INTVAL (XEXP (SET_SRC (set), 1));
4804 gcc_assert (REG_P (XEXP (SET_SRC (set), 1))
4805 && (REGNO (XEXP (SET_SRC (set), 1))
4806 < FIRST_PSEUDO_REGISTER)
4807 && p->const_equiv[REGNO (XEXP (SET_SRC (set), 1))]);
4809 = INTVAL (p->const_equiv[REGNO (XEXP (SET_SRC (set), 1))]);
4813 p->new_sp_equiv_reg = SET_SRC (set), p->new_sp_offset = 0;
4815 /* If we are adjusting SP, we adjust from the old data. */
4816 if (p->new_sp_equiv_reg == stack_pointer_rtx)
4818 p->new_sp_equiv_reg = p->sp_equiv_reg;
4819 p->new_sp_offset += p->sp_offset;
4822 gcc_assert (p->new_sp_equiv_reg && REG_P (p->new_sp_equiv_reg));
4827 /* Next handle the case where we are setting SP's equivalent
4828 register. We must not already have a value to set it to. We
4829 could update, but there seems little point in handling that case.
4830 Note that we have to allow for the case where we are setting the
4831 register set in the previous part of a PARALLEL inside a single
4832 insn. But use the old offset for any updates within this insn.
4833 We must allow for the case where the register is being set in a
4834 different (usually wider) mode than Pmode). */
4835 else if (p->new_sp_equiv_reg != 0 && reg_set_p (p->new_sp_equiv_reg, set))
4837 gcc_assert (!p->equiv_reg_src
4838 && REG_P (p->new_sp_equiv_reg)
4839 && REG_P (SET_DEST (set))
4840 && (GET_MODE_BITSIZE (GET_MODE (SET_DEST (set)))
4842 && REGNO (p->new_sp_equiv_reg) == REGNO (SET_DEST (set)));
4844 = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
4845 plus_constant (p->sp_equiv_reg,
4849 /* Otherwise, replace any references to SP in the insn to its new value
4850 and emit the insn. */
4853 SET_SRC (set) = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
4854 plus_constant (p->sp_equiv_reg,
4856 SET_DEST (set) = simplify_replace_rtx (SET_DEST (set), stack_pointer_rtx,
4857 plus_constant (p->sp_equiv_reg,
4863 /* Update the tracking information for registers set to constants. */
4866 update_epilogue_consts (rtx dest, rtx x, void *data)
4868 struct epi_info *p = (struct epi_info *) data;
4871 if (!REG_P (dest) || REGNO (dest) >= FIRST_PSEUDO_REGISTER)
4874 /* If we are either clobbering a register or doing a partial set,
4875 show we don't know the value. */
4876 else if (GET_CODE (x) == CLOBBER || ! rtx_equal_p (dest, SET_DEST (x)))
4877 p->const_equiv[REGNO (dest)] = 0;
4879 /* If we are setting it to a constant, record that constant. */
4880 else if (GET_CODE (SET_SRC (x)) == CONST_INT)
4881 p->const_equiv[REGNO (dest)] = SET_SRC (x);
4883 /* If this is a binary operation between a register we have been tracking
4884 and a constant, see if we can compute a new constant value. */
4885 else if (ARITHMETIC_P (SET_SRC (x))
4886 && REG_P (XEXP (SET_SRC (x), 0))
4887 && REGNO (XEXP (SET_SRC (x), 0)) < FIRST_PSEUDO_REGISTER
4888 && p->const_equiv[REGNO (XEXP (SET_SRC (x), 0))] != 0
4889 && GET_CODE (XEXP (SET_SRC (x), 1)) == CONST_INT
4890 && 0 != (new = simplify_binary_operation
4891 (GET_CODE (SET_SRC (x)), GET_MODE (dest),
4892 p->const_equiv[REGNO (XEXP (SET_SRC (x), 0))],
4893 XEXP (SET_SRC (x), 1)))
4894 && GET_CODE (new) == CONST_INT)
4895 p->const_equiv[REGNO (dest)] = new;
4897 /* Otherwise, we can't do anything with this value. */
4899 p->const_equiv[REGNO (dest)] = 0;
4902 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
4905 emit_equiv_load (struct epi_info *p)
4907 if (p->equiv_reg_src != 0)
4909 rtx dest = p->sp_equiv_reg;
4911 if (GET_MODE (p->equiv_reg_src) != GET_MODE (dest))
4912 dest = gen_rtx_REG (GET_MODE (p->equiv_reg_src),
4913 REGNO (p->sp_equiv_reg));
4915 emit_move_insn (dest, p->equiv_reg_src);
4916 p->equiv_reg_src = 0;
4921 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
4922 this into place with notes indicating where the prologue ends and where
4923 the epilogue begins. Update the basic block information when possible. */
4926 thread_prologue_and_epilogue_insns (rtx f ATTRIBUTE_UNUSED)
4930 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
4933 #ifdef HAVE_prologue
4934 rtx prologue_end = NULL_RTX;
4936 #if defined (HAVE_epilogue) || defined(HAVE_return)
4937 rtx epilogue_end = NULL_RTX;
4941 #ifdef HAVE_prologue
4945 seq = gen_prologue ();
4948 /* Retain a map of the prologue insns. */
4949 record_insns (seq, &prologue);
4950 prologue_end = emit_note (NOTE_INSN_PROLOGUE_END);
4954 set_insn_locators (seq, prologue_locator);
4956 /* Can't deal with multiple successors of the entry block
4957 at the moment. Function should always have at least one
4959 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR));
4961 insert_insn_on_edge (seq, single_succ_edge (ENTRY_BLOCK_PTR));
4966 /* If the exit block has no non-fake predecessors, we don't need
4968 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
4969 if ((e->flags & EDGE_FAKE) == 0)
4975 if (optimize && HAVE_return)
4977 /* If we're allowed to generate a simple return instruction,
4978 then by definition we don't need a full epilogue. Examine
4979 the block that falls through to EXIT. If it does not
4980 contain any code, examine its predecessors and try to
4981 emit (conditional) return instructions. */
4986 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
4987 if (e->flags & EDGE_FALLTHRU)
4993 /* Verify that there are no active instructions in the last block. */
4994 label = BB_END (last);
4995 while (label && !LABEL_P (label))
4997 if (active_insn_p (label))
4999 label = PREV_INSN (label);
5002 if (BB_HEAD (last) == label && LABEL_P (label))
5005 rtx epilogue_line_note = NULL_RTX;
5007 /* Locate the line number associated with the closing brace,
5008 if we can find one. */
5009 for (seq = get_last_insn ();
5010 seq && ! active_insn_p (seq);
5011 seq = PREV_INSN (seq))
5012 if (NOTE_P (seq) && NOTE_LINE_NUMBER (seq) > 0)
5014 epilogue_line_note = seq;
5018 for (ei2 = ei_start (last->preds); (e = ei_safe_edge (ei2)); )
5020 basic_block bb = e->src;
5023 if (bb == ENTRY_BLOCK_PTR)
5030 if (!JUMP_P (jump) || JUMP_LABEL (jump) != label)
5036 /* If we have an unconditional jump, we can replace that
5037 with a simple return instruction. */
5038 if (simplejump_p (jump))
5040 emit_return_into_block (bb, epilogue_line_note);
5044 /* If we have a conditional jump, we can try to replace
5045 that with a conditional return instruction. */
5046 else if (condjump_p (jump))
5048 if (! redirect_jump (jump, 0, 0))
5054 /* If this block has only one successor, it both jumps
5055 and falls through to the fallthru block, so we can't
5057 if (single_succ_p (bb))
5069 /* Fix up the CFG for the successful change we just made. */
5070 redirect_edge_succ (e, EXIT_BLOCK_PTR);
5073 /* Emit a return insn for the exit fallthru block. Whether
5074 this is still reachable will be determined later. */
5076 emit_barrier_after (BB_END (last));
5077 emit_return_into_block (last, epilogue_line_note);
5078 epilogue_end = BB_END (last);
5079 single_succ_edge (last)->flags &= ~EDGE_FALLTHRU;
5084 /* Find the edge that falls through to EXIT. Other edges may exist
5085 due to RETURN instructions, but those don't need epilogues.
5086 There really shouldn't be a mixture -- either all should have
5087 been converted or none, however... */
5089 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5090 if (e->flags & EDGE_FALLTHRU)
5095 #ifdef HAVE_epilogue
5099 epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG);
5101 seq = gen_epilogue ();
5103 #ifdef INCOMING_RETURN_ADDR_RTX
5104 /* If this function returns with the stack depressed and we can support
5105 it, massage the epilogue to actually do that. */
5106 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
5107 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
5108 seq = keep_stack_depressed (seq);
5111 emit_jump_insn (seq);
5113 /* Retain a map of the epilogue insns. */
5114 record_insns (seq, &epilogue);
5115 set_insn_locators (seq, epilogue_locator);
5120 insert_insn_on_edge (seq, e);
5128 if (! next_active_insn (BB_END (e->src)))
5130 /* We have a fall-through edge to the exit block, the source is not
5131 at the end of the function, and there will be an assembler epilogue
5132 at the end of the function.
5133 We can't use force_nonfallthru here, because that would try to
5134 use return. Inserting a jump 'by hand' is extremely messy, so
5135 we take advantage of cfg_layout_finalize using
5136 fixup_fallthru_exit_predecessor. */
5137 cfg_layout_initialize (0);
5138 FOR_EACH_BB (cur_bb)
5139 if (cur_bb->index >= 0 && cur_bb->next_bb->index >= 0)
5140 cur_bb->rbi->next = cur_bb->next_bb;
5141 cfg_layout_finalize ();
5146 commit_edge_insertions ();
5148 #ifdef HAVE_sibcall_epilogue
5149 /* Emit sibling epilogues before any sibling call sites. */
5150 for (ei = ei_start (EXIT_BLOCK_PTR->preds); (e = ei_safe_edge (ei)); )
5152 basic_block bb = e->src;
5153 rtx insn = BB_END (bb);
5156 || ! SIBLING_CALL_P (insn))
5163 emit_insn (gen_sibcall_epilogue ());
5167 /* Retain a map of the epilogue insns. Used in life analysis to
5168 avoid getting rid of sibcall epilogue insns. Do this before we
5169 actually emit the sequence. */
5170 record_insns (seq, &sibcall_epilogue);
5171 set_insn_locators (seq, epilogue_locator);
5173 emit_insn_before (seq, insn);
5178 #ifdef HAVE_prologue
5179 /* This is probably all useless now that we use locators. */
5184 /* GDB handles `break f' by setting a breakpoint on the first
5185 line note after the prologue. Which means (1) that if
5186 there are line number notes before where we inserted the
5187 prologue we should move them, and (2) we should generate a
5188 note before the end of the first basic block, if there isn't
5191 ??? This behavior is completely broken when dealing with
5192 multiple entry functions. We simply place the note always
5193 into first basic block and let alternate entry points
5197 for (insn = prologue_end; insn; insn = prev)
5199 prev = PREV_INSN (insn);
5200 if (NOTE_P (insn) && NOTE_LINE_NUMBER (insn) > 0)
5202 /* Note that we cannot reorder the first insn in the
5203 chain, since rest_of_compilation relies on that
5204 remaining constant. */
5207 reorder_insns (insn, insn, prologue_end);
5211 /* Find the last line number note in the first block. */
5212 for (insn = BB_END (ENTRY_BLOCK_PTR->next_bb);
5213 insn != prologue_end && insn;
5214 insn = PREV_INSN (insn))
5215 if (NOTE_P (insn) && NOTE_LINE_NUMBER (insn) > 0)
5218 /* If we didn't find one, make a copy of the first line number
5222 for (insn = next_active_insn (prologue_end);
5224 insn = PREV_INSN (insn))
5225 if (NOTE_P (insn) && NOTE_LINE_NUMBER (insn) > 0)
5227 emit_note_copy_after (insn, prologue_end);
5233 #ifdef HAVE_epilogue
5238 /* Similarly, move any line notes that appear after the epilogue.
5239 There is no need, however, to be quite so anal about the existence
5240 of such a note. Also move the NOTE_INSN_FUNCTION_END and (possibly)
5241 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
5243 for (insn = epilogue_end; insn; insn = next)
5245 next = NEXT_INSN (insn);
5247 && (NOTE_LINE_NUMBER (insn) > 0
5248 || NOTE_LINE_NUMBER (insn) == NOTE_INSN_FUNCTION_BEG
5249 || NOTE_LINE_NUMBER (insn) == NOTE_INSN_FUNCTION_END))
5250 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
5256 /* Reposition the prologue-end and epilogue-begin notes after instruction
5257 scheduling and delayed branch scheduling. */
5260 reposition_prologue_and_epilogue_notes (rtx f ATTRIBUTE_UNUSED)
5262 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
5263 rtx insn, last, note;
5266 if ((len = VARRAY_SIZE (prologue)) > 0)
5270 /* Scan from the beginning until we reach the last prologue insn.
5271 We apparently can't depend on basic_block_{head,end} after
5273 for (insn = f; insn; insn = NEXT_INSN (insn))
5277 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
5280 else if (contains (insn, prologue))
5290 /* Find the prologue-end note if we haven't already, and
5291 move it to just after the last prologue insn. */
5294 for (note = last; (note = NEXT_INSN (note));)
5296 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
5300 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
5302 last = NEXT_INSN (last);
5303 reorder_insns (note, note, last);
5307 if ((len = VARRAY_SIZE (epilogue)) > 0)
5311 /* Scan from the end until we reach the first epilogue insn.
5312 We apparently can't depend on basic_block_{head,end} after
5314 for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
5318 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
5321 else if (contains (insn, epilogue))
5331 /* Find the epilogue-begin note if we haven't already, and
5332 move it to just before the first epilogue insn. */
5335 for (note = insn; (note = PREV_INSN (note));)
5337 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
5341 if (PREV_INSN (last) != note)
5342 reorder_insns (note, note, PREV_INSN (last));
5345 #endif /* HAVE_prologue or HAVE_epilogue */
5348 /* Called once, at initialization, to initialize function.c. */
5351 init_function_once (void)
5353 VARRAY_INT_INIT (prologue, 0, "prologue");
5354 VARRAY_INT_INIT (epilogue, 0, "epilogue");
5355 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");
5358 /* Resets insn_block_boundaries array. */
5361 reset_block_changes (void)
5363 VARRAY_TREE_INIT (cfun->ib_boundaries_block, 100, "ib_boundaries_block");
5364 VARRAY_PUSH_TREE (cfun->ib_boundaries_block, NULL_TREE);
5367 /* Record the boundary for BLOCK. */
5369 record_block_change (tree block)
5377 last_block = VARRAY_TOP_TREE (cfun->ib_boundaries_block);
5378 VARRAY_POP (cfun->ib_boundaries_block);
5380 for (i = VARRAY_ACTIVE_SIZE (cfun->ib_boundaries_block); i < n; i++)
5381 VARRAY_PUSH_TREE (cfun->ib_boundaries_block, last_block);
5383 VARRAY_PUSH_TREE (cfun->ib_boundaries_block, block);
5386 /* Finishes record of boundaries. */
5387 void finalize_block_changes (void)
5389 record_block_change (DECL_INITIAL (current_function_decl));
5392 /* For INSN return the BLOCK it belongs to. */
5394 check_block_change (rtx insn, tree *block)
5396 unsigned uid = INSN_UID (insn);
5398 if (uid >= VARRAY_ACTIVE_SIZE (cfun->ib_boundaries_block))
5401 *block = VARRAY_TREE (cfun->ib_boundaries_block, uid);
5404 /* Releases the ib_boundaries_block records. */
5406 free_block_changes (void)
5408 cfun->ib_boundaries_block = NULL;
5411 /* Returns the name of the current function. */
5413 current_function_name (void)
5415 return lang_hooks.decl_printable_name (cfun->decl, 2);
5418 #include "gt-function.h"