1 /* Expands front end tree to back end RTL for GCC.
2 Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
22 /* This file handles the generation of rtl code from tree structure
23 at the level of the function as a whole.
24 It creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 `expand_function_start' is called at the beginning of a function,
28 before the function body is parsed, and `expand_function_end' is
29 called after parsing the body.
31 Call `assign_stack_local' to allocate a stack slot for a local variable.
32 This is usually done during the RTL generation for the function body,
33 but it can also be done in the reload pass when a pseudo-register does
34 not get a hard register.
36 Call `put_var_into_stack' when you learn, belatedly, that a variable
37 previously given a pseudo-register must in fact go in the stack.
38 This function changes the DECL_RTL to be a stack slot instead of a reg
39 then scans all the RTL instructions so far generated to correct them. */
43 #include "coretypes.h"
54 #include "hard-reg-set.h"
55 #include "insn-config.h"
58 #include "basic-block.h"
63 #include "integrate.h"
64 #include "langhooks.h"
66 #include "cfglayout.h"
68 #ifndef LOCAL_ALIGNMENT
69 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
72 #ifndef STACK_ALIGNMENT_NEEDED
73 #define STACK_ALIGNMENT_NEEDED 1
76 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
78 /* Some systems use __main in a way incompatible with its use in gcc, in these
79 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
80 give the same symbol without quotes for an alternative entry point. You
81 must define both, or neither. */
83 #define NAME__MAIN "__main"
86 /* Round a value to the lowest integer less than it that is a multiple of
87 the required alignment. Avoid using division in case the value is
88 negative. Assume the alignment is a power of two. */
89 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
91 /* Similar, but round to the next highest integer that meets the
93 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
95 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
96 during rtl generation. If they are different register numbers, this is
97 always true. It may also be true if
98 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
99 generation. See fix_lexical_addr for details. */
101 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
102 #define NEED_SEPARATE_AP
105 /* Nonzero if function being compiled doesn't contain any calls
106 (ignoring the prologue and epilogue). This is set prior to
107 local register allocation and is valid for the remaining
109 int current_function_is_leaf;
111 /* Nonzero if function being compiled doesn't contain any instructions
112 that can throw an exception. This is set prior to final. */
114 int current_function_nothrow;
116 /* Nonzero if function being compiled doesn't modify the stack pointer
117 (ignoring the prologue and epilogue). This is only valid after
118 life_analysis has run. */
119 int current_function_sp_is_unchanging;
121 /* Nonzero if the function being compiled is a leaf function which only
122 uses leaf registers. This is valid after reload (specifically after
123 sched2) and is useful only if the port defines LEAF_REGISTERS. */
124 int current_function_uses_only_leaf_regs;
126 /* Nonzero once virtual register instantiation has been done.
127 assign_stack_local uses frame_pointer_rtx when this is nonzero.
128 calls.c:emit_library_call_value_1 uses it to set up
129 post-instantiation libcalls. */
130 int virtuals_instantiated;
132 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
133 static GTY(()) int funcdef_no;
135 /* These variables hold pointers to functions to create and destroy
136 target specific, per-function data structures. */
137 struct machine_function * (*init_machine_status) (void);
139 /* The currently compiled function. */
140 struct function *cfun = 0;
142 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
143 static GTY(()) varray_type prologue;
144 static GTY(()) varray_type epilogue;
146 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
148 static GTY(()) varray_type sibcall_epilogue;
150 /* In order to evaluate some expressions, such as function calls returning
151 structures in memory, we need to temporarily allocate stack locations.
152 We record each allocated temporary in the following structure.
154 Associated with each temporary slot is a nesting level. When we pop up
155 one level, all temporaries associated with the previous level are freed.
156 Normally, all temporaries are freed after the execution of the statement
157 in which they were created. However, if we are inside a ({...}) grouping,
158 the result may be in a temporary and hence must be preserved. If the
159 result could be in a temporary, we preserve it if we can determine which
160 one it is in. If we cannot determine which temporary may contain the
161 result, all temporaries are preserved. A temporary is preserved by
162 pretending it was allocated at the previous nesting level.
164 Automatic variables are also assigned temporary slots, at the nesting
165 level where they are defined. They are marked a "kept" so that
166 free_temp_slots will not free them. */
168 struct temp_slot GTY(())
170 /* Points to next temporary slot. */
171 struct temp_slot *next;
172 /* Points to previous temporary slot. */
173 struct temp_slot *prev;
175 /* The rtx to used to reference the slot. */
177 /* The rtx used to represent the address if not the address of the
178 slot above. May be an EXPR_LIST if multiple addresses exist. */
180 /* The alignment (in bits) of the slot. */
182 /* The size, in units, of the slot. */
184 /* The type of the object in the slot, or zero if it doesn't correspond
185 to a type. We use this to determine whether a slot can be reused.
186 It can be reused if objects of the type of the new slot will always
187 conflict with objects of the type of the old slot. */
189 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
191 /* Nonzero if this temporary is currently in use. */
193 /* Nonzero if this temporary has its address taken. */
195 /* Nesting level at which this slot is being used. */
197 /* Nonzero if this should survive a call to free_temp_slots. */
199 /* The offset of the slot from the frame_pointer, including extra space
200 for alignment. This info is for combine_temp_slots. */
201 HOST_WIDE_INT base_offset;
202 /* The size of the slot, including extra space for alignment. This
203 info is for combine_temp_slots. */
204 HOST_WIDE_INT full_size;
207 /* This structure is used to record MEMs or pseudos used to replace VAR, any
208 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
209 maintain this list in case two operands of an insn were required to match;
210 in that case we must ensure we use the same replacement. */
212 struct fixup_replacement GTY(())
216 struct fixup_replacement *next;
219 struct insns_for_mem_entry
223 /* These are the INSNs which reference the MEM. */
227 /* Forward declarations. */
229 static rtx assign_stack_local_1 (enum machine_mode, HOST_WIDE_INT, int,
231 static struct temp_slot *find_temp_slot_from_address (rtx);
232 static void put_reg_into_stack (struct function *, rtx, tree, enum machine_mode,
233 unsigned int, bool, bool, bool, htab_t);
234 static void schedule_fixup_var_refs (struct function *, rtx, tree, enum machine_mode,
236 static void fixup_var_refs (rtx, enum machine_mode, int, rtx, htab_t);
237 static struct fixup_replacement
238 *find_fixup_replacement (struct fixup_replacement **, rtx);
239 static void fixup_var_refs_insns (rtx, rtx, enum machine_mode, int, int, rtx);
240 static void fixup_var_refs_insns_with_hash (htab_t, rtx, enum machine_mode, int, rtx);
241 static void fixup_var_refs_insn (rtx, rtx, enum machine_mode, int, int, rtx);
242 static void fixup_var_refs_1 (rtx, enum machine_mode, rtx *, rtx,
243 struct fixup_replacement **, rtx);
244 static rtx fixup_memory_subreg (rtx, rtx, enum machine_mode, int);
245 static rtx walk_fixup_memory_subreg (rtx, rtx, rtx, enum machine_mode, int);
246 static rtx fixup_stack_1 (rtx, rtx);
247 static void optimize_bit_field (rtx, rtx, rtx *);
248 static void instantiate_decls (tree, int);
249 static void instantiate_decls_1 (tree, int);
250 static void instantiate_decl (rtx, HOST_WIDE_INT, int);
251 static rtx instantiate_new_reg (rtx, HOST_WIDE_INT *);
252 static int instantiate_virtual_regs_1 (rtx *, rtx, int);
253 static void pad_to_arg_alignment (struct args_size *, int, struct args_size *);
254 static void pad_below (struct args_size *, enum machine_mode, tree);
255 static tree *identify_blocks_1 (rtx, tree *, tree *, tree *);
256 static void reorder_blocks_1 (rtx, tree, varray_type *);
257 static void reorder_fix_fragments (tree);
258 static int all_blocks (tree, tree *);
259 static tree *get_block_vector (tree, int *);
260 extern tree debug_find_var_in_block_tree (tree, tree);
261 /* We always define `record_insns' even if it's not used so that we
262 can always export `prologue_epilogue_contains'. */
263 static void record_insns (rtx, varray_type *) ATTRIBUTE_UNUSED;
264 static int contains (rtx, varray_type);
266 static void emit_return_into_block (basic_block, rtx);
268 static void put_addressof_into_stack (rtx, htab_t);
269 static bool purge_addressof_1 (rtx *, rtx, int, int, int, htab_t);
270 static void purge_single_hard_subreg_set (rtx);
271 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
272 static rtx keep_stack_depressed (rtx);
274 static int is_addressof (rtx *, void *);
275 static hashval_t insns_for_mem_hash (const void *);
276 static int insns_for_mem_comp (const void *, const void *);
277 static int insns_for_mem_walk (rtx *, void *);
278 static void compute_insns_for_mem (rtx, rtx, htab_t);
279 static void prepare_function_start (tree);
280 static void do_clobber_return_reg (rtx, void *);
281 static void do_use_return_reg (rtx, void *);
282 static void instantiate_virtual_regs_lossage (rtx);
283 static tree split_complex_args (tree);
284 static void set_insn_locators (rtx, int) ATTRIBUTE_UNUSED;
286 /* Pointer to chain of `struct function' for containing functions. */
287 struct function *outer_function_chain;
289 /* List of insns that were postponed by purge_addressof_1. */
290 static rtx postponed_insns;
292 /* Given a function decl for a containing function,
293 return the `struct function' for it. */
296 find_function_data (tree decl)
300 for (p = outer_function_chain; p; p = p->outer)
307 /* Save the current context for compilation of a nested function.
308 This is called from language-specific code. The caller should use
309 the enter_nested langhook to save any language-specific state,
310 since this function knows only about language-independent
314 push_function_context_to (tree context)
320 if (context == current_function_decl)
321 cfun->contains_functions = 1;
324 struct function *containing = find_function_data (context);
325 containing->contains_functions = 1;
330 init_dummy_function_start ();
333 p->outer = outer_function_chain;
334 outer_function_chain = p;
335 p->fixup_var_refs_queue = 0;
337 lang_hooks.function.enter_nested (p);
343 push_function_context (void)
345 push_function_context_to (current_function_decl);
348 /* Restore the last saved context, at the end of a nested function.
349 This function is called from language-specific code. */
352 pop_function_context_from (tree context ATTRIBUTE_UNUSED)
354 struct function *p = outer_function_chain;
355 struct var_refs_queue *queue;
358 outer_function_chain = p->outer;
360 current_function_decl = p->decl;
363 restore_emit_status (p);
365 lang_hooks.function.leave_nested (p);
367 /* Finish doing put_var_into_stack for any of our variables which became
368 addressable during the nested function. If only one entry has to be
369 fixed up, just do that one. Otherwise, first make a list of MEMs that
370 are not to be unshared. */
371 if (p->fixup_var_refs_queue == 0)
373 else if (p->fixup_var_refs_queue->next == 0)
374 fixup_var_refs (p->fixup_var_refs_queue->modified,
375 p->fixup_var_refs_queue->promoted_mode,
376 p->fixup_var_refs_queue->unsignedp,
377 p->fixup_var_refs_queue->modified, 0);
382 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
383 list = gen_rtx_EXPR_LIST (VOIDmode, queue->modified, list);
385 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
386 fixup_var_refs (queue->modified, queue->promoted_mode,
387 queue->unsignedp, list, 0);
391 p->fixup_var_refs_queue = 0;
393 /* Reset variables that have known state during rtx generation. */
394 rtx_equal_function_value_matters = 1;
395 virtuals_instantiated = 0;
396 generating_concat_p = 1;
400 pop_function_context (void)
402 pop_function_context_from (current_function_decl);
405 /* Clear out all parts of the state in F that can safely be discarded
406 after the function has been parsed, but not compiled, to let
407 garbage collection reclaim the memory. */
410 free_after_parsing (struct function *f)
412 /* f->expr->forced_labels is used by code generation. */
413 /* f->emit->regno_reg_rtx is used by code generation. */
414 /* f->varasm is used by code generation. */
415 /* f->eh->eh_return_stub_label is used by code generation. */
417 lang_hooks.function.final (f);
421 /* Clear out all parts of the state in F that can safely be discarded
422 after the function has been compiled, to let garbage collection
423 reclaim the memory. */
426 free_after_compilation (struct function *f)
434 f->x_avail_temp_slots = NULL;
435 f->x_used_temp_slots = NULL;
436 f->arg_offset_rtx = NULL;
437 f->return_rtx = NULL;
438 f->internal_arg_pointer = NULL;
439 f->x_nonlocal_goto_handler_labels = NULL;
440 f->x_cleanup_label = NULL;
441 f->x_return_label = NULL;
442 f->x_naked_return_label = NULL;
443 f->x_save_expr_regs = NULL;
444 f->x_stack_slot_list = NULL;
445 f->x_rtl_expr_chain = NULL;
446 f->x_tail_recursion_reentry = NULL;
447 f->x_arg_pointer_save_area = NULL;
448 f->x_parm_birth_insn = NULL;
449 f->x_last_parm_insn = NULL;
450 f->x_parm_reg_stack_loc = NULL;
451 f->fixup_var_refs_queue = NULL;
452 f->original_arg_vector = NULL;
453 f->original_decl_initial = NULL;
454 f->inl_last_parm_insn = NULL;
455 f->epilogue_delay_list = NULL;
458 /* Allocate fixed slots in the stack frame of the current function. */
460 /* Return size needed for stack frame based on slots so far allocated in
462 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
463 the caller may have to do that. */
466 get_func_frame_size (struct function *f)
468 #ifdef FRAME_GROWS_DOWNWARD
469 return -f->x_frame_offset;
471 return f->x_frame_offset;
475 /* Return size needed for stack frame based on slots so far allocated.
476 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
477 the caller may have to do that. */
479 get_frame_size (void)
481 return get_func_frame_size (cfun);
484 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
485 with machine mode MODE.
487 ALIGN controls the amount of alignment for the address of the slot:
488 0 means according to MODE,
489 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
490 -2 means use BITS_PER_UNIT,
491 positive specifies alignment boundary in bits.
493 We do not round to stack_boundary here.
495 FUNCTION specifies the function to allocate in. */
498 assign_stack_local_1 (enum machine_mode mode, HOST_WIDE_INT size, int align,
499 struct function *function)
502 int bigend_correction = 0;
504 int frame_off, frame_alignment, frame_phase;
511 alignment = BIGGEST_ALIGNMENT;
513 alignment = GET_MODE_ALIGNMENT (mode);
515 /* Allow the target to (possibly) increase the alignment of this
517 type = lang_hooks.types.type_for_mode (mode, 0);
519 alignment = LOCAL_ALIGNMENT (type, alignment);
521 alignment /= BITS_PER_UNIT;
523 else if (align == -1)
525 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
526 size = CEIL_ROUND (size, alignment);
528 else if (align == -2)
529 alignment = 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
531 alignment = align / BITS_PER_UNIT;
533 #ifdef FRAME_GROWS_DOWNWARD
534 function->x_frame_offset -= size;
537 /* Ignore alignment we can't do with expected alignment of the boundary. */
538 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
539 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
541 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
542 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
544 /* Calculate how many bytes the start of local variables is off from
546 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
547 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
548 frame_phase = frame_off ? frame_alignment - frame_off : 0;
550 /* Round the frame offset to the specified alignment. The default is
551 to always honor requests to align the stack but a port may choose to
552 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
553 if (STACK_ALIGNMENT_NEEDED
557 /* We must be careful here, since FRAME_OFFSET might be negative and
558 division with a negative dividend isn't as well defined as we might
559 like. So we instead assume that ALIGNMENT is a power of two and
560 use logical operations which are unambiguous. */
561 #ifdef FRAME_GROWS_DOWNWARD
562 function->x_frame_offset
563 = (FLOOR_ROUND (function->x_frame_offset - frame_phase, alignment)
566 function->x_frame_offset
567 = (CEIL_ROUND (function->x_frame_offset - frame_phase, alignment)
572 /* On a big-endian machine, if we are allocating more space than we will use,
573 use the least significant bytes of those that are allocated. */
574 if (BYTES_BIG_ENDIAN && mode != BLKmode)
575 bigend_correction = size - GET_MODE_SIZE (mode);
577 /* If we have already instantiated virtual registers, return the actual
578 address relative to the frame pointer. */
579 if (function == cfun && virtuals_instantiated)
580 addr = plus_constant (frame_pointer_rtx,
582 (frame_offset + bigend_correction
583 + STARTING_FRAME_OFFSET, Pmode));
585 addr = plus_constant (virtual_stack_vars_rtx,
587 (function->x_frame_offset + bigend_correction,
590 #ifndef FRAME_GROWS_DOWNWARD
591 function->x_frame_offset += size;
594 x = gen_rtx_MEM (mode, addr);
596 function->x_stack_slot_list
597 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
602 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
606 assign_stack_local (enum machine_mode mode, HOST_WIDE_INT size, int align)
608 return assign_stack_local_1 (mode, size, align, cfun);
612 /* Removes temporary slot TEMP from LIST. */
615 cut_slot_from_list (struct temp_slot *temp, struct temp_slot **list)
618 temp->next->prev = temp->prev;
620 temp->prev->next = temp->next;
624 temp->prev = temp->next = NULL;
627 /* Inserts temporary slot TEMP to LIST. */
630 insert_slot_to_list (struct temp_slot *temp, struct temp_slot **list)
634 (*list)->prev = temp;
639 /* Returns the list of used temp slots at LEVEL. */
641 static struct temp_slot **
642 temp_slots_at_level (int level)
646 if (!used_temp_slots)
647 VARRAY_GENERIC_PTR_INIT (used_temp_slots, 3, "used_temp_slots");
649 while (level >= (int) VARRAY_ACTIVE_SIZE (used_temp_slots))
650 VARRAY_PUSH_GENERIC_PTR (used_temp_slots, NULL);
652 return (struct temp_slot **) &VARRAY_GENERIC_PTR (used_temp_slots, level);
655 /* Returns the maximal temporary slot level. */
658 max_slot_level (void)
660 if (!used_temp_slots)
663 return VARRAY_ACTIVE_SIZE (used_temp_slots) - 1;
666 /* Moves temporary slot TEMP to LEVEL. */
669 move_slot_to_level (struct temp_slot *temp, int level)
671 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
672 insert_slot_to_list (temp, temp_slots_at_level (level));
676 /* Make temporary slot TEMP available. */
679 make_slot_available (struct temp_slot *temp)
681 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
682 insert_slot_to_list (temp, &avail_temp_slots);
687 /* Allocate a temporary stack slot and record it for possible later
690 MODE is the machine mode to be given to the returned rtx.
692 SIZE is the size in units of the space required. We do no rounding here
693 since assign_stack_local will do any required rounding.
695 KEEP is 1 if this slot is to be retained after a call to
696 free_temp_slots. Automatic variables for a block are allocated
697 with this flag. KEEP is 2 if we allocate a longer term temporary,
698 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
699 if we are to allocate something at an inner level to be treated as
700 a variable in the block (e.g., a SAVE_EXPR).
702 TYPE is the type that will be used for the stack slot. */
705 assign_stack_temp_for_type (enum machine_mode mode, HOST_WIDE_INT size, int keep,
709 struct temp_slot *p, *best_p = 0, *selected = NULL, **pp;
712 /* If SIZE is -1 it means that somebody tried to allocate a temporary
713 of a variable size. */
718 align = BIGGEST_ALIGNMENT;
720 align = GET_MODE_ALIGNMENT (mode);
723 type = lang_hooks.types.type_for_mode (mode, 0);
726 align = LOCAL_ALIGNMENT (type, align);
728 /* Try to find an available, already-allocated temporary of the proper
729 mode which meets the size and alignment requirements. Choose the
730 smallest one with the closest alignment. */
731 for (p = avail_temp_slots; p; p = p->next)
733 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
734 && objects_must_conflict_p (p->type, type)
735 && (best_p == 0 || best_p->size > p->size
736 || (best_p->size == p->size && best_p->align > p->align)))
738 if (p->align == align && p->size == size)
741 cut_slot_from_list (selected, &avail_temp_slots);
749 /* Make our best, if any, the one to use. */
753 cut_slot_from_list (selected, &avail_temp_slots);
755 /* If there are enough aligned bytes left over, make them into a new
756 temp_slot so that the extra bytes don't get wasted. Do this only
757 for BLKmode slots, so that we can be sure of the alignment. */
758 if (GET_MODE (best_p->slot) == BLKmode)
760 int alignment = best_p->align / BITS_PER_UNIT;
761 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
763 if (best_p->size - rounded_size >= alignment)
765 p = ggc_alloc (sizeof (struct temp_slot));
766 p->in_use = p->addr_taken = 0;
767 p->size = best_p->size - rounded_size;
768 p->base_offset = best_p->base_offset + rounded_size;
769 p->full_size = best_p->full_size - rounded_size;
770 p->slot = gen_rtx_MEM (BLKmode,
771 plus_constant (XEXP (best_p->slot, 0),
773 p->align = best_p->align;
776 p->type = best_p->type;
777 insert_slot_to_list (p, &avail_temp_slots);
779 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
782 best_p->size = rounded_size;
783 best_p->full_size = rounded_size;
788 /* If we still didn't find one, make a new temporary. */
791 HOST_WIDE_INT frame_offset_old = frame_offset;
793 p = ggc_alloc (sizeof (struct temp_slot));
795 /* We are passing an explicit alignment request to assign_stack_local.
796 One side effect of that is assign_stack_local will not round SIZE
797 to ensure the frame offset remains suitably aligned.
799 So for requests which depended on the rounding of SIZE, we go ahead
800 and round it now. We also make sure ALIGNMENT is at least
801 BIGGEST_ALIGNMENT. */
802 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
804 p->slot = assign_stack_local (mode,
806 ? CEIL_ROUND (size, (int) align / BITS_PER_UNIT)
812 /* The following slot size computation is necessary because we don't
813 know the actual size of the temporary slot until assign_stack_local
814 has performed all the frame alignment and size rounding for the
815 requested temporary. Note that extra space added for alignment
816 can be either above or below this stack slot depending on which
817 way the frame grows. We include the extra space if and only if it
818 is above this slot. */
819 #ifdef FRAME_GROWS_DOWNWARD
820 p->size = frame_offset_old - frame_offset;
825 /* Now define the fields used by combine_temp_slots. */
826 #ifdef FRAME_GROWS_DOWNWARD
827 p->base_offset = frame_offset;
828 p->full_size = frame_offset_old - frame_offset;
830 p->base_offset = frame_offset_old;
831 p->full_size = frame_offset - frame_offset_old;
841 p->rtl_expr = seq_rtl_expr;
846 p->level = target_temp_slot_level;
851 p->level = var_temp_slot_level;
856 p->level = temp_slot_level;
860 pp = temp_slots_at_level (p->level);
861 insert_slot_to_list (p, pp);
863 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
864 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
865 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list);
867 /* If we know the alias set for the memory that will be used, use
868 it. If there's no TYPE, then we don't know anything about the
869 alias set for the memory. */
870 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
871 set_mem_align (slot, align);
873 /* If a type is specified, set the relevant flags. */
876 RTX_UNCHANGING_P (slot) = (lang_hooks.honor_readonly
877 && TYPE_READONLY (type));
878 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
879 MEM_SET_IN_STRUCT_P (slot, AGGREGATE_TYPE_P (type));
885 /* Allocate a temporary stack slot and record it for possible later
886 reuse. First three arguments are same as in preceding function. */
889 assign_stack_temp (enum machine_mode mode, HOST_WIDE_INT size, int keep)
891 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
894 /* Assign a temporary.
895 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
896 and so that should be used in error messages. In either case, we
897 allocate of the given type.
898 KEEP is as for assign_stack_temp.
899 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
900 it is 0 if a register is OK.
901 DONT_PROMOTE is 1 if we should not promote values in register
905 assign_temp (tree type_or_decl, int keep, int memory_required,
906 int dont_promote ATTRIBUTE_UNUSED)
909 enum machine_mode mode;
914 if (DECL_P (type_or_decl))
915 decl = type_or_decl, type = TREE_TYPE (decl);
917 decl = NULL, type = type_or_decl;
919 mode = TYPE_MODE (type);
921 unsignedp = TYPE_UNSIGNED (type);
924 if (mode == BLKmode || memory_required)
926 HOST_WIDE_INT size = int_size_in_bytes (type);
929 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
930 problems with allocating the stack space. */
934 /* Unfortunately, we don't yet know how to allocate variable-sized
935 temporaries. However, sometimes we have a fixed upper limit on
936 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
937 instead. This is the case for Chill variable-sized strings. */
938 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
939 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
940 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
941 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
943 /* The size of the temporary may be too large to fit into an integer. */
944 /* ??? Not sure this should happen except for user silliness, so limit
945 this to things that aren't compiler-generated temporaries. The
946 rest of the time we'll abort in assign_stack_temp_for_type. */
947 if (decl && size == -1
948 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
950 error ("%Jsize of variable '%D' is too large", decl, decl);
954 tmp = assign_stack_temp_for_type (mode, size, keep, type);
960 mode = promote_mode (type, mode, &unsignedp, 0);
963 return gen_reg_rtx (mode);
966 /* Combine temporary stack slots which are adjacent on the stack.
968 This allows for better use of already allocated stack space. This is only
969 done for BLKmode slots because we can be sure that we won't have alignment
970 problems in this case. */
973 combine_temp_slots (void)
975 struct temp_slot *p, *q, *next, *next_q;
978 /* We can't combine slots, because the information about which slot
979 is in which alias set will be lost. */
980 if (flag_strict_aliasing)
983 /* If there are a lot of temp slots, don't do anything unless
984 high levels of optimization. */
985 if (! flag_expensive_optimizations)
986 for (p = avail_temp_slots, num_slots = 0; p; p = p->next, num_slots++)
987 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
990 for (p = avail_temp_slots; p; p = next)
996 if (GET_MODE (p->slot) != BLKmode)
999 for (q = p->next; q; q = next_q)
1005 if (GET_MODE (q->slot) != BLKmode)
1008 if (p->base_offset + p->full_size == q->base_offset)
1010 /* Q comes after P; combine Q into P. */
1012 p->full_size += q->full_size;
1015 else if (q->base_offset + q->full_size == p->base_offset)
1017 /* P comes after Q; combine P into Q. */
1019 q->full_size += p->full_size;
1024 cut_slot_from_list (q, &avail_temp_slots);
1027 /* Either delete P or advance past it. */
1029 cut_slot_from_list (p, &avail_temp_slots);
1033 /* Find the temp slot corresponding to the object at address X. */
1035 static struct temp_slot *
1036 find_temp_slot_from_address (rtx x)
1038 struct temp_slot *p;
1042 for (i = max_slot_level (); i >= 0; i--)
1043 for (p = *temp_slots_at_level (i); p; p = p->next)
1045 if (XEXP (p->slot, 0) == x
1047 || (GET_CODE (x) == PLUS
1048 && XEXP (x, 0) == virtual_stack_vars_rtx
1049 && GET_CODE (XEXP (x, 1)) == CONST_INT
1050 && INTVAL (XEXP (x, 1)) >= p->base_offset
1051 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
1054 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
1055 for (next = p->address; next; next = XEXP (next, 1))
1056 if (XEXP (next, 0) == x)
1060 /* If we have a sum involving a register, see if it points to a temp
1062 if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 0))
1063 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
1065 else if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 1))
1066 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
1072 /* Indicate that NEW is an alternate way of referring to the temp slot
1073 that previously was known by OLD. */
1076 update_temp_slot_address (rtx old, rtx new)
1078 struct temp_slot *p;
1080 if (rtx_equal_p (old, new))
1083 p = find_temp_slot_from_address (old);
1085 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
1086 is a register, see if one operand of the PLUS is a temporary
1087 location. If so, NEW points into it. Otherwise, if both OLD and
1088 NEW are a PLUS and if there is a register in common between them.
1089 If so, try a recursive call on those values. */
1092 if (GET_CODE (old) != PLUS)
1097 update_temp_slot_address (XEXP (old, 0), new);
1098 update_temp_slot_address (XEXP (old, 1), new);
1101 else if (GET_CODE (new) != PLUS)
1104 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
1105 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
1106 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
1107 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
1108 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
1109 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
1110 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
1111 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
1116 /* Otherwise add an alias for the temp's address. */
1117 else if (p->address == 0)
1121 if (GET_CODE (p->address) != EXPR_LIST)
1122 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1124 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1128 /* If X could be a reference to a temporary slot, mark the fact that its
1129 address was taken. */
1132 mark_temp_addr_taken (rtx x)
1134 struct temp_slot *p;
1139 /* If X is not in memory or is at a constant address, it cannot be in
1140 a temporary slot. */
1141 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1144 p = find_temp_slot_from_address (XEXP (x, 0));
1149 /* If X could be a reference to a temporary slot, mark that slot as
1150 belonging to the to one level higher than the current level. If X
1151 matched one of our slots, just mark that one. Otherwise, we can't
1152 easily predict which it is, so upgrade all of them. Kept slots
1153 need not be touched.
1155 This is called when an ({...}) construct occurs and a statement
1156 returns a value in memory. */
1159 preserve_temp_slots (rtx x)
1161 struct temp_slot *p = 0, *next;
1163 /* If there is no result, we still might have some objects whose address
1164 were taken, so we need to make sure they stay around. */
1167 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1172 move_slot_to_level (p, temp_slot_level - 1);
1178 /* If X is a register that is being used as a pointer, see if we have
1179 a temporary slot we know it points to. To be consistent with
1180 the code below, we really should preserve all non-kept slots
1181 if we can't find a match, but that seems to be much too costly. */
1182 if (REG_P (x) && REG_POINTER (x))
1183 p = find_temp_slot_from_address (x);
1185 /* If X is not in memory or is at a constant address, it cannot be in
1186 a temporary slot, but it can contain something whose address was
1188 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1190 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1195 move_slot_to_level (p, temp_slot_level - 1);
1201 /* First see if we can find a match. */
1203 p = find_temp_slot_from_address (XEXP (x, 0));
1207 /* Move everything at our level whose address was taken to our new
1208 level in case we used its address. */
1209 struct temp_slot *q;
1211 if (p->level == temp_slot_level)
1213 for (q = *temp_slots_at_level (temp_slot_level); q; q = next)
1217 if (p != q && q->addr_taken)
1218 move_slot_to_level (q, temp_slot_level - 1);
1221 move_slot_to_level (p, temp_slot_level - 1);
1227 /* Otherwise, preserve all non-kept slots at this level. */
1228 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1233 move_slot_to_level (p, temp_slot_level - 1);
1237 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1238 with that RTL_EXPR, promote it into a temporary slot at the present
1239 level so it will not be freed when we free slots made in the
1243 preserve_rtl_expr_result (rtx x)
1245 struct temp_slot *p;
1247 /* If X is not in memory or is at a constant address, it cannot be in
1248 a temporary slot. */
1249 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1252 /* If we can find a match, move it to our level unless it is already at
1254 p = find_temp_slot_from_address (XEXP (x, 0));
1257 move_slot_to_level (p, MIN (p->level, temp_slot_level));
1264 /* Free all temporaries used so far. This is normally called at the end
1265 of generating code for a statement. Don't free any temporaries
1266 currently in use for an RTL_EXPR that hasn't yet been emitted.
1267 We could eventually do better than this since it can be reused while
1268 generating the same RTL_EXPR, but this is complex and probably not
1272 free_temp_slots (void)
1274 struct temp_slot *p, *next;
1276 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1280 if (!p->keep && p->rtl_expr == 0)
1281 make_slot_available (p);
1284 combine_temp_slots ();
1287 /* Free all temporary slots used in T, an RTL_EXPR node. */
1290 free_temps_for_rtl_expr (tree t)
1292 struct temp_slot *p, *next;
1294 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1298 if (p->rtl_expr == t)
1300 /* If this slot is below the current TEMP_SLOT_LEVEL, then it
1301 needs to be preserved. This can happen if a temporary in
1302 the RTL_EXPR was addressed; preserve_temp_slots will move
1303 the temporary into a higher level. */
1304 if (temp_slot_level <= p->level)
1305 make_slot_available (p);
1307 p->rtl_expr = NULL_TREE;
1311 combine_temp_slots ();
1314 /* Push deeper into the nesting level for stack temporaries. */
1317 push_temp_slots (void)
1322 /* Pop a temporary nesting level. All slots in use in the current level
1326 pop_temp_slots (void)
1328 struct temp_slot *p, *next;
1330 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1334 if (p->rtl_expr == 0)
1335 make_slot_available (p);
1338 combine_temp_slots ();
1343 /* Initialize temporary slots. */
1346 init_temp_slots (void)
1348 /* We have not allocated any temporaries yet. */
1349 avail_temp_slots = 0;
1350 used_temp_slots = 0;
1351 temp_slot_level = 0;
1352 var_temp_slot_level = 0;
1353 target_temp_slot_level = 0;
1356 /* Retroactively move an auto variable from a register to a stack
1357 slot. This is done when an address-reference to the variable is
1358 seen. If RESCAN is true, all previously emitted instructions are
1359 examined and modified to handle the fact that DECL is now
1363 put_var_into_stack (tree decl, int rescan)
1366 enum machine_mode promoted_mode, decl_mode;
1367 struct function *function = 0;
1369 bool can_use_addressof_p;
1370 bool volatile_p = TREE_CODE (decl) != SAVE_EXPR && TREE_THIS_VOLATILE (decl);
1371 bool used_p = (TREE_USED (decl)
1372 || (TREE_CODE (decl) != SAVE_EXPR && DECL_INITIAL (decl) != 0));
1374 context = decl_function_context (decl);
1376 /* Get the current rtl used for this object and its original mode. */
1377 orig_reg = reg = (TREE_CODE (decl) == SAVE_EXPR
1378 ? SAVE_EXPR_RTL (decl)
1379 : DECL_RTL_IF_SET (decl));
1381 /* No need to do anything if decl has no rtx yet
1382 since in that case caller is setting TREE_ADDRESSABLE
1383 and a stack slot will be assigned when the rtl is made. */
1387 /* Get the declared mode for this object. */
1388 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1389 : DECL_MODE (decl));
1390 /* Get the mode it's actually stored in. */
1391 promoted_mode = GET_MODE (reg);
1393 /* If this variable comes from an outer function, find that
1394 function's saved context. Don't use find_function_data here,
1395 because it might not be in any active function.
1396 FIXME: Is that really supposed to happen?
1397 It does in ObjC at least. */
1398 if (context != current_function_decl)
1399 for (function = outer_function_chain; function; function = function->outer)
1400 if (function->decl == context)
1403 /* If this is a variable-sized object or a structure passed by invisible
1404 reference, with a pseudo to address it, put that pseudo into the stack
1405 if the var is non-local. */
1406 if (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl)
1407 && GET_CODE (reg) == MEM
1408 && REG_P (XEXP (reg, 0))
1409 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1411 orig_reg = reg = XEXP (reg, 0);
1412 decl_mode = promoted_mode = GET_MODE (reg);
1415 /* If this variable lives in the current function and we don't need to put it
1416 in the stack for the sake of setjmp or the non-locality, try to keep it in
1417 a register until we know we actually need the address. */
1420 && ! (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl))
1422 /* FIXME make it work for promoted modes too */
1423 && decl_mode == promoted_mode
1424 #ifdef NON_SAVING_SETJMP
1425 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1429 /* If we can't use ADDRESSOF, make sure we see through one we already
1431 if (! can_use_addressof_p
1432 && GET_CODE (reg) == MEM
1433 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1434 reg = XEXP (XEXP (reg, 0), 0);
1436 /* Now we should have a value that resides in one or more pseudo regs. */
1440 if (can_use_addressof_p)
1441 gen_mem_addressof (reg, decl, rescan);
1443 put_reg_into_stack (function, reg, TREE_TYPE (decl), decl_mode,
1444 0, volatile_p, used_p, false, 0);
1446 /* If this was previously a MEM but we've removed the ADDRESSOF,
1447 set this address into that MEM so we always use the same
1448 rtx for this variable. */
1449 if (orig_reg != reg && GET_CODE (orig_reg) == MEM)
1450 XEXP (orig_reg, 0) = XEXP (reg, 0);
1452 else if (GET_CODE (reg) == CONCAT)
1454 /* A CONCAT contains two pseudos; put them both in the stack.
1455 We do it so they end up consecutive.
1456 We fixup references to the parts only after we fixup references
1457 to the whole CONCAT, lest we do double fixups for the latter
1459 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1460 tree part_type = lang_hooks.types.type_for_mode (part_mode, 0);
1461 rtx lopart = XEXP (reg, 0);
1462 rtx hipart = XEXP (reg, 1);
1463 #ifdef FRAME_GROWS_DOWNWARD
1464 /* Since part 0 should have a lower address, do it second. */
1465 put_reg_into_stack (function, hipart, part_type, part_mode,
1466 0, volatile_p, false, false, 0);
1467 put_reg_into_stack (function, lopart, part_type, part_mode,
1468 0, volatile_p, false, true, 0);
1470 put_reg_into_stack (function, lopart, part_type, part_mode,
1471 0, volatile_p, false, false, 0);
1472 put_reg_into_stack (function, hipart, part_type, part_mode,
1473 0, volatile_p, false, true, 0);
1476 /* Change the CONCAT into a combined MEM for both parts. */
1477 PUT_CODE (reg, MEM);
1478 MEM_ATTRS (reg) = 0;
1480 /* set_mem_attributes uses DECL_RTL to avoid re-generating of
1481 already computed alias sets. Here we want to re-generate. */
1483 SET_DECL_RTL (decl, NULL);
1484 set_mem_attributes (reg, decl, 1);
1486 SET_DECL_RTL (decl, reg);
1488 /* The two parts are in memory order already.
1489 Use the lower parts address as ours. */
1490 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1491 /* Prevent sharing of rtl that might lose. */
1492 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1493 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1494 if (used_p && rescan)
1496 schedule_fixup_var_refs (function, reg, TREE_TYPE (decl),
1498 schedule_fixup_var_refs (function, lopart, part_type, part_mode, 0);
1499 schedule_fixup_var_refs (function, hipart, part_type, part_mode, 0);
1506 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1507 into the stack frame of FUNCTION (0 means the current function).
1508 TYPE is the user-level data type of the value hold in the register.
1509 DECL_MODE is the machine mode of the user-level data type.
1510 ORIGINAL_REGNO must be set if the real regno is not visible in REG.
1511 VOLATILE_P is true if this is for a "volatile" decl.
1512 USED_P is true if this reg might have already been used in an insn.
1513 CONSECUTIVE_P is true if the stack slot assigned to reg must be
1514 consecutive with the previous stack slot. */
1517 put_reg_into_stack (struct function *function, rtx reg, tree type,
1518 enum machine_mode decl_mode, unsigned int original_regno,
1519 bool volatile_p, bool used_p, bool consecutive_p,
1522 struct function *func = function ? function : cfun;
1523 enum machine_mode mode = GET_MODE (reg);
1524 unsigned int regno = original_regno;
1528 regno = REGNO (reg);
1530 if (regno < func->x_max_parm_reg)
1532 if (!func->x_parm_reg_stack_loc)
1534 new = func->x_parm_reg_stack_loc[regno];
1538 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode),
1539 consecutive_p ? -2 : 0, func);
1541 PUT_CODE (reg, MEM);
1542 PUT_MODE (reg, decl_mode);
1543 XEXP (reg, 0) = XEXP (new, 0);
1544 MEM_ATTRS (reg) = 0;
1545 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1546 MEM_VOLATILE_P (reg) = volatile_p;
1548 /* If this is a memory ref that contains aggregate components,
1549 mark it as such for cse and loop optimize. If we are reusing a
1550 previously generated stack slot, then we need to copy the bit in
1551 case it was set for other reasons. For instance, it is set for
1552 __builtin_va_alist. */
1555 MEM_SET_IN_STRUCT_P (reg,
1556 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1557 set_mem_alias_set (reg, get_alias_set (type));
1561 schedule_fixup_var_refs (function, reg, type, mode, ht);
1564 /* Make sure that all refs to the variable, previously made
1565 when it was a register, are fixed up to be valid again.
1566 See function above for meaning of arguments. */
1569 schedule_fixup_var_refs (struct function *function, rtx reg, tree type,
1570 enum machine_mode promoted_mode, htab_t ht)
1572 int unsigned_p = type ? TYPE_UNSIGNED (type) : 0;
1576 struct var_refs_queue *temp;
1578 temp = ggc_alloc (sizeof (struct var_refs_queue));
1579 temp->modified = reg;
1580 temp->promoted_mode = promoted_mode;
1581 temp->unsignedp = unsigned_p;
1582 temp->next = function->fixup_var_refs_queue;
1583 function->fixup_var_refs_queue = temp;
1586 /* Variable is local; fix it up now. */
1587 fixup_var_refs (reg, promoted_mode, unsigned_p, reg, ht);
1591 fixup_var_refs (rtx var, enum machine_mode promoted_mode, int unsignedp,
1592 rtx may_share, htab_t ht)
1595 rtx first_insn = get_insns ();
1596 struct sequence_stack *stack = seq_stack;
1597 tree rtl_exps = rtl_expr_chain;
1598 int save_volatile_ok = volatile_ok;
1600 /* If there's a hash table, it must record all uses of VAR. */
1605 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp,
1610 /* Volatile is valid in MEMs because all we're doing in changing the
1613 fixup_var_refs_insns (first_insn, var, promoted_mode, unsignedp,
1614 stack == 0, may_share);
1616 /* Scan all pending sequences too. */
1617 for (; stack; stack = stack->next)
1619 push_to_full_sequence (stack->first, stack->last);
1620 fixup_var_refs_insns (stack->first, var, promoted_mode, unsignedp,
1621 stack->next != 0, may_share);
1622 /* Update bounds of sequence in case we added insns. */
1623 stack->first = get_insns ();
1624 stack->last = get_last_insn ();
1628 /* Scan all waiting RTL_EXPRs too. */
1629 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1631 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1632 if (seq != const0_rtx && seq != 0)
1634 push_to_sequence (seq);
1635 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1641 volatile_ok = save_volatile_ok;
1644 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1645 some part of an insn. Return a struct fixup_replacement whose OLD
1646 value is equal to X. Allocate a new structure if no such entry exists. */
1648 static struct fixup_replacement *
1649 find_fixup_replacement (struct fixup_replacement **replacements, rtx x)
1651 struct fixup_replacement *p;
1653 /* See if we have already replaced this. */
1654 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1659 p = xmalloc (sizeof (struct fixup_replacement));
1662 p->next = *replacements;
1669 /* Scan the insn-chain starting with INSN for refs to VAR and fix them
1670 up. TOPLEVEL is nonzero if this chain is the main chain of insns
1671 for the current function. MAY_SHARE is either a MEM that is not
1672 to be unshared or a list of them. */
1675 fixup_var_refs_insns (rtx insn, rtx var, enum machine_mode promoted_mode,
1676 int unsignedp, int toplevel, rtx may_share)
1680 /* fixup_var_refs_insn might modify insn, so save its next
1682 rtx next = NEXT_INSN (insn);
1685 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel,
1692 /* Look up the insns which reference VAR in HT and fix them up. Other
1693 arguments are the same as fixup_var_refs_insns. */
1696 fixup_var_refs_insns_with_hash (htab_t ht, rtx var, enum machine_mode promoted_mode,
1697 int unsignedp, rtx may_share)
1699 struct insns_for_mem_entry tmp;
1700 struct insns_for_mem_entry *ime;
1704 ime = htab_find (ht, &tmp);
1705 for (insn_list = ime->insns; insn_list != 0; insn_list = XEXP (insn_list, 1))
1706 if (INSN_P (XEXP (insn_list, 0)))
1707 fixup_var_refs_insn (XEXP (insn_list, 0), var, promoted_mode,
1708 unsignedp, 1, may_share);
1712 /* Per-insn processing by fixup_var_refs_insns(_with_hash). INSN is
1713 the insn under examination, VAR is the variable to fix up
1714 references to, PROMOTED_MODE and UNSIGNEDP describe VAR, and
1715 TOPLEVEL is nonzero if this is the main insn chain for this
1719 fixup_var_refs_insn (rtx insn, rtx var, enum machine_mode promoted_mode,
1720 int unsignedp, int toplevel, rtx no_share)
1723 rtx set, prev, prev_set;
1726 /* Remember the notes in case we delete the insn. */
1727 note = REG_NOTES (insn);
1729 /* If this is a CLOBBER of VAR, delete it.
1731 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1732 and REG_RETVAL notes too. */
1733 if (GET_CODE (PATTERN (insn)) == CLOBBER
1734 && (XEXP (PATTERN (insn), 0) == var
1735 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1736 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1737 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1739 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1740 /* The REG_LIBCALL note will go away since we are going to
1741 turn INSN into a NOTE, so just delete the
1742 corresponding REG_RETVAL note. */
1743 remove_note (XEXP (note, 0),
1744 find_reg_note (XEXP (note, 0), REG_RETVAL,
1750 /* The insn to load VAR from a home in the arglist
1751 is now a no-op. When we see it, just delete it.
1752 Similarly if this is storing VAR from a register from which
1753 it was loaded in the previous insn. This will occur
1754 when an ADDRESSOF was made for an arglist slot. */
1756 && (set = single_set (insn)) != 0
1757 && SET_DEST (set) == var
1758 /* If this represents the result of an insn group,
1759 don't delete the insn. */
1760 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1761 && (rtx_equal_p (SET_SRC (set), var)
1762 || (REG_P (SET_SRC (set))
1763 && (prev = prev_nonnote_insn (insn)) != 0
1764 && (prev_set = single_set (prev)) != 0
1765 && SET_DEST (prev_set) == SET_SRC (set)
1766 && rtx_equal_p (SET_SRC (prev_set), var))))
1772 struct fixup_replacement *replacements = 0;
1773 rtx next_insn = NEXT_INSN (insn);
1775 if (SMALL_REGISTER_CLASSES)
1777 /* If the insn that copies the results of a CALL_INSN
1778 into a pseudo now references VAR, we have to use an
1779 intermediate pseudo since we want the life of the
1780 return value register to be only a single insn.
1782 If we don't use an intermediate pseudo, such things as
1783 address computations to make the address of VAR valid
1784 if it is not can be placed between the CALL_INSN and INSN.
1786 To make sure this doesn't happen, we record the destination
1787 of the CALL_INSN and see if the next insn uses both that
1790 if (call_dest != 0 && GET_CODE (insn) == INSN
1791 && reg_mentioned_p (var, PATTERN (insn))
1792 && reg_mentioned_p (call_dest, PATTERN (insn)))
1794 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1796 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1798 PATTERN (insn) = replace_rtx (PATTERN (insn),
1802 if (GET_CODE (insn) == CALL_INSN
1803 && GET_CODE (PATTERN (insn)) == SET)
1804 call_dest = SET_DEST (PATTERN (insn));
1805 else if (GET_CODE (insn) == CALL_INSN
1806 && GET_CODE (PATTERN (insn)) == PARALLEL
1807 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1808 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1813 /* See if we have to do anything to INSN now that VAR is in
1814 memory. If it needs to be loaded into a pseudo, use a single
1815 pseudo for the entire insn in case there is a MATCH_DUP
1816 between two operands. We pass a pointer to the head of
1817 a list of struct fixup_replacements. If fixup_var_refs_1
1818 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1819 it will record them in this list.
1821 If it allocated a pseudo for any replacement, we copy into
1824 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1825 &replacements, no_share);
1827 /* If this is last_parm_insn, and any instructions were output
1828 after it to fix it up, then we must set last_parm_insn to
1829 the last such instruction emitted. */
1830 if (insn == last_parm_insn)
1831 last_parm_insn = PREV_INSN (next_insn);
1833 while (replacements)
1835 struct fixup_replacement *next;
1837 if (REG_P (replacements->new))
1842 /* OLD might be a (subreg (mem)). */
1843 if (GET_CODE (replacements->old) == SUBREG)
1845 = fixup_memory_subreg (replacements->old, insn,
1849 = fixup_stack_1 (replacements->old, insn);
1851 insert_before = insn;
1853 /* If we are changing the mode, do a conversion.
1854 This might be wasteful, but combine.c will
1855 eliminate much of the waste. */
1857 if (GET_MODE (replacements->new)
1858 != GET_MODE (replacements->old))
1861 convert_move (replacements->new,
1862 replacements->old, unsignedp);
1867 seq = gen_move_insn (replacements->new,
1870 emit_insn_before (seq, insert_before);
1873 next = replacements->next;
1874 free (replacements);
1875 replacements = next;
1879 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1880 But don't touch other insns referred to by reg-notes;
1881 we will get them elsewhere. */
1884 if (GET_CODE (note) != INSN_LIST)
1886 = walk_fixup_memory_subreg (XEXP (note, 0), insn, var,
1888 note = XEXP (note, 1);
1892 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1893 See if the rtx expression at *LOC in INSN needs to be changed.
1895 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1896 contain a list of original rtx's and replacements. If we find that we need
1897 to modify this insn by replacing a memory reference with a pseudo or by
1898 making a new MEM to implement a SUBREG, we consult that list to see if
1899 we have already chosen a replacement. If none has already been allocated,
1900 we allocate it and update the list. fixup_var_refs_insn will copy VAR
1901 or the SUBREG, as appropriate, to the pseudo. */
1904 fixup_var_refs_1 (rtx var, enum machine_mode promoted_mode, rtx *loc, rtx insn,
1905 struct fixup_replacement **replacements, rtx no_share)
1909 RTX_CODE code = GET_CODE (x);
1912 struct fixup_replacement *replacement;
1917 if (XEXP (x, 0) == var)
1919 /* Prevent sharing of rtl that might lose. */
1920 rtx sub = copy_rtx (XEXP (var, 0));
1922 if (! validate_change (insn, loc, sub, 0))
1924 rtx y = gen_reg_rtx (GET_MODE (sub));
1927 /* We should be able to replace with a register or all is lost.
1928 Note that we can't use validate_change to verify this, since
1929 we're not caring for replacing all dups simultaneously. */
1930 if (! validate_replace_rtx (*loc, y, insn))
1933 /* Careful! First try to recognize a direct move of the
1934 value, mimicking how things are done in gen_reload wrt
1935 PLUS. Consider what happens when insn is a conditional
1936 move instruction and addsi3 clobbers flags. */
1939 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1943 if (recog_memoized (new_insn) < 0)
1945 /* That failed. Fall back on force_operand and hope. */
1948 sub = force_operand (sub, y);
1950 emit_insn (gen_move_insn (y, sub));
1956 /* Don't separate setter from user. */
1957 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1958 insn = PREV_INSN (insn);
1961 emit_insn_before (seq, insn);
1969 /* If we already have a replacement, use it. Otherwise,
1970 try to fix up this address in case it is invalid. */
1972 replacement = find_fixup_replacement (replacements, var);
1973 if (replacement->new)
1975 *loc = replacement->new;
1979 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1981 /* Unless we are forcing memory to register or we changed the mode,
1982 we can leave things the way they are if the insn is valid. */
1984 INSN_CODE (insn) = -1;
1985 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1986 && recog_memoized (insn) >= 0)
1989 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1993 /* If X contains VAR, we need to unshare it here so that we update
1994 each occurrence separately. But all identical MEMs in one insn
1995 must be replaced with the same rtx because of the possibility of
1998 if (reg_mentioned_p (var, x))
2000 replacement = find_fixup_replacement (replacements, x);
2001 if (replacement->new == 0)
2002 replacement->new = copy_most_rtx (x, no_share);
2004 *loc = x = replacement->new;
2005 code = GET_CODE (x);
2022 /* Note that in some cases those types of expressions are altered
2023 by optimize_bit_field, and do not survive to get here. */
2024 if (XEXP (x, 0) == var
2025 || (GET_CODE (XEXP (x, 0)) == SUBREG
2026 && SUBREG_REG (XEXP (x, 0)) == var))
2028 /* Get TEM as a valid MEM in the mode presently in the insn.
2030 We don't worry about the possibility of MATCH_DUP here; it
2031 is highly unlikely and would be tricky to handle. */
2034 if (GET_CODE (tem) == SUBREG)
2036 if (GET_MODE_BITSIZE (GET_MODE (tem))
2037 > GET_MODE_BITSIZE (GET_MODE (var)))
2039 replacement = find_fixup_replacement (replacements, var);
2040 if (replacement->new == 0)
2041 replacement->new = gen_reg_rtx (GET_MODE (var));
2042 SUBREG_REG (tem) = replacement->new;
2044 /* The following code works only if we have a MEM, so we
2045 need to handle the subreg here. We directly substitute
2046 it assuming that a subreg must be OK here. We already
2047 scheduled a replacement to copy the mem into the
2053 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
2056 tem = fixup_stack_1 (tem, insn);
2058 /* Unless we want to load from memory, get TEM into the proper mode
2059 for an extract from memory. This can only be done if the
2060 extract is at a constant position and length. */
2062 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
2063 && GET_CODE (XEXP (x, 2)) == CONST_INT
2064 && ! mode_dependent_address_p (XEXP (tem, 0))
2065 && ! MEM_VOLATILE_P (tem))
2067 enum machine_mode wanted_mode = VOIDmode;
2068 enum machine_mode is_mode = GET_MODE (tem);
2069 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
2071 if (GET_CODE (x) == ZERO_EXTRACT)
2073 enum machine_mode new_mode
2074 = mode_for_extraction (EP_extzv, 1);
2075 if (new_mode != MAX_MACHINE_MODE)
2076 wanted_mode = new_mode;
2078 else if (GET_CODE (x) == SIGN_EXTRACT)
2080 enum machine_mode new_mode
2081 = mode_for_extraction (EP_extv, 1);
2082 if (new_mode != MAX_MACHINE_MODE)
2083 wanted_mode = new_mode;
2086 /* If we have a narrower mode, we can do something. */
2087 if (wanted_mode != VOIDmode
2088 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2090 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2091 rtx old_pos = XEXP (x, 2);
2094 /* If the bytes and bits are counted differently, we
2095 must adjust the offset. */
2096 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2097 offset = (GET_MODE_SIZE (is_mode)
2098 - GET_MODE_SIZE (wanted_mode) - offset);
2100 pos %= GET_MODE_BITSIZE (wanted_mode);
2102 newmem = adjust_address_nv (tem, wanted_mode, offset);
2104 /* Make the change and see if the insn remains valid. */
2105 INSN_CODE (insn) = -1;
2106 XEXP (x, 0) = newmem;
2107 XEXP (x, 2) = GEN_INT (pos);
2109 if (recog_memoized (insn) >= 0)
2112 /* Otherwise, restore old position. XEXP (x, 0) will be
2114 XEXP (x, 2) = old_pos;
2118 /* If we get here, the bitfield extract insn can't accept a memory
2119 reference. Copy the input into a register. */
2121 tem1 = gen_reg_rtx (GET_MODE (tem));
2122 emit_insn_before (gen_move_insn (tem1, tem), insn);
2129 if (SUBREG_REG (x) == var)
2131 /* If this is a special SUBREG made because VAR was promoted
2132 from a wider mode, replace it with VAR and call ourself
2133 recursively, this time saying that the object previously
2134 had its current mode (by virtue of the SUBREG). */
2136 if (SUBREG_PROMOTED_VAR_P (x))
2139 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements,
2144 /* If this SUBREG makes VAR wider, it has become a paradoxical
2145 SUBREG with VAR in memory, but these aren't allowed at this
2146 stage of the compilation. So load VAR into a pseudo and take
2147 a SUBREG of that pseudo. */
2148 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2150 replacement = find_fixup_replacement (replacements, var);
2151 if (replacement->new == 0)
2152 replacement->new = gen_reg_rtx (promoted_mode);
2153 SUBREG_REG (x) = replacement->new;
2157 /* See if we have already found a replacement for this SUBREG.
2158 If so, use it. Otherwise, make a MEM and see if the insn
2159 is recognized. If not, or if we should force MEM into a register,
2160 make a pseudo for this SUBREG. */
2161 replacement = find_fixup_replacement (replacements, x);
2162 if (replacement->new)
2164 enum machine_mode mode = GET_MODE (x);
2165 *loc = replacement->new;
2167 /* Careful! We may have just replaced a SUBREG by a MEM, which
2168 means that the insn may have become invalid again. We can't
2169 in this case make a new replacement since we already have one
2170 and we must deal with MATCH_DUPs. */
2171 if (GET_CODE (replacement->new) == MEM)
2173 INSN_CODE (insn) = -1;
2174 if (recog_memoized (insn) >= 0)
2177 fixup_var_refs_1 (replacement->new, mode, &PATTERN (insn),
2178 insn, replacements, no_share);
2184 replacement->new = *loc = fixup_memory_subreg (x, insn,
2187 INSN_CODE (insn) = -1;
2188 if (! flag_force_mem && recog_memoized (insn) >= 0)
2191 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2197 /* First do special simplification of bit-field references. */
2198 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2199 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2200 optimize_bit_field (x, insn, 0);
2201 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2202 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2203 optimize_bit_field (x, insn, 0);
2205 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2206 into a register and then store it back out. */
2207 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2208 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2209 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2210 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2211 > GET_MODE_SIZE (GET_MODE (var))))
2213 replacement = find_fixup_replacement (replacements, var);
2214 if (replacement->new == 0)
2215 replacement->new = gen_reg_rtx (GET_MODE (var));
2217 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2218 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2221 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2222 insn into a pseudo and store the low part of the pseudo into VAR. */
2223 if (GET_CODE (SET_DEST (x)) == SUBREG
2224 && SUBREG_REG (SET_DEST (x)) == var
2225 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2226 > GET_MODE_SIZE (GET_MODE (var))))
2228 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2229 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2236 rtx dest = SET_DEST (x);
2237 rtx src = SET_SRC (x);
2238 rtx outerdest = dest;
2240 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2241 || GET_CODE (dest) == SIGN_EXTRACT
2242 || GET_CODE (dest) == ZERO_EXTRACT)
2243 dest = XEXP (dest, 0);
2245 if (GET_CODE (src) == SUBREG)
2246 src = SUBREG_REG (src);
2248 /* If VAR does not appear at the top level of the SET
2249 just scan the lower levels of the tree. */
2251 if (src != var && dest != var)
2254 /* We will need to rerecognize this insn. */
2255 INSN_CODE (insn) = -1;
2257 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var
2258 && mode_for_extraction (EP_insv, -1) != MAX_MACHINE_MODE)
2260 /* Since this case will return, ensure we fixup all the
2262 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2263 insn, replacements, no_share);
2264 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2265 insn, replacements, no_share);
2266 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2267 insn, replacements, no_share);
2269 tem = XEXP (outerdest, 0);
2271 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2272 that may appear inside a ZERO_EXTRACT.
2273 This was legitimate when the MEM was a REG. */
2274 if (GET_CODE (tem) == SUBREG
2275 && SUBREG_REG (tem) == var)
2276 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
2278 tem = fixup_stack_1 (tem, insn);
2280 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2281 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2282 && ! mode_dependent_address_p (XEXP (tem, 0))
2283 && ! MEM_VOLATILE_P (tem))
2285 enum machine_mode wanted_mode;
2286 enum machine_mode is_mode = GET_MODE (tem);
2287 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2289 wanted_mode = mode_for_extraction (EP_insv, 0);
2291 /* If we have a narrower mode, we can do something. */
2292 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2294 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2295 rtx old_pos = XEXP (outerdest, 2);
2298 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2299 offset = (GET_MODE_SIZE (is_mode)
2300 - GET_MODE_SIZE (wanted_mode) - offset);
2302 pos %= GET_MODE_BITSIZE (wanted_mode);
2304 newmem = adjust_address_nv (tem, wanted_mode, offset);
2306 /* Make the change and see if the insn remains valid. */
2307 INSN_CODE (insn) = -1;
2308 XEXP (outerdest, 0) = newmem;
2309 XEXP (outerdest, 2) = GEN_INT (pos);
2311 if (recog_memoized (insn) >= 0)
2314 /* Otherwise, restore old position. XEXP (x, 0) will be
2316 XEXP (outerdest, 2) = old_pos;
2320 /* If we get here, the bit-field store doesn't allow memory
2321 or isn't located at a constant position. Load the value into
2322 a register, do the store, and put it back into memory. */
2324 tem1 = gen_reg_rtx (GET_MODE (tem));
2325 emit_insn_before (gen_move_insn (tem1, tem), insn);
2326 emit_insn_after (gen_move_insn (tem, tem1), insn);
2327 XEXP (outerdest, 0) = tem1;
2331 /* STRICT_LOW_PART is a no-op on memory references
2332 and it can cause combinations to be unrecognizable,
2335 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2336 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2338 /* A valid insn to copy VAR into or out of a register
2339 must be left alone, to avoid an infinite loop here.
2340 If the reference to VAR is by a subreg, fix that up,
2341 since SUBREG is not valid for a memref.
2342 Also fix up the address of the stack slot.
2344 Note that we must not try to recognize the insn until
2345 after we know that we have valid addresses and no
2346 (subreg (mem ...) ...) constructs, since these interfere
2347 with determining the validity of the insn. */
2349 if ((SET_SRC (x) == var
2350 || (GET_CODE (SET_SRC (x)) == SUBREG
2351 && SUBREG_REG (SET_SRC (x)) == var))
2352 && (REG_P (SET_DEST (x))
2353 || (GET_CODE (SET_DEST (x)) == SUBREG
2354 && REG_P (SUBREG_REG (SET_DEST (x)))))
2355 && GET_MODE (var) == promoted_mode
2356 && x == single_set (insn))
2360 if (GET_CODE (SET_SRC (x)) == SUBREG
2361 && (GET_MODE_SIZE (GET_MODE (SET_SRC (x)))
2362 > GET_MODE_SIZE (GET_MODE (var))))
2364 /* This (subreg VAR) is now a paradoxical subreg. We need
2365 to replace VAR instead of the subreg. */
2366 replacement = find_fixup_replacement (replacements, var);
2367 if (replacement->new == NULL_RTX)
2368 replacement->new = gen_reg_rtx (GET_MODE (var));
2369 SUBREG_REG (SET_SRC (x)) = replacement->new;
2373 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2374 if (replacement->new)
2375 SET_SRC (x) = replacement->new;
2376 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2377 SET_SRC (x) = replacement->new
2378 = fixup_memory_subreg (SET_SRC (x), insn, promoted_mode,
2381 SET_SRC (x) = replacement->new
2382 = fixup_stack_1 (SET_SRC (x), insn);
2385 if (recog_memoized (insn) >= 0)
2388 /* INSN is not valid, but we know that we want to
2389 copy SET_SRC (x) to SET_DEST (x) in some way. So
2390 we generate the move and see whether it requires more
2391 than one insn. If it does, we emit those insns and
2392 delete INSN. Otherwise, we can just replace the pattern
2393 of INSN; we have already verified above that INSN has
2394 no other function that to do X. */
2396 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2397 if (NEXT_INSN (pat) != NULL_RTX)
2399 last = emit_insn_before (pat, insn);
2401 /* INSN might have REG_RETVAL or other important notes, so
2402 we need to store the pattern of the last insn in the
2403 sequence into INSN similarly to the normal case. LAST
2404 should not have REG_NOTES, but we allow them if INSN has
2406 if (REG_NOTES (last) && REG_NOTES (insn))
2408 if (REG_NOTES (last))
2409 REG_NOTES (insn) = REG_NOTES (last);
2410 PATTERN (insn) = PATTERN (last);
2415 PATTERN (insn) = PATTERN (pat);
2420 if ((SET_DEST (x) == var
2421 || (GET_CODE (SET_DEST (x)) == SUBREG
2422 && SUBREG_REG (SET_DEST (x)) == var))
2423 && (REG_P (SET_SRC (x))
2424 || (GET_CODE (SET_SRC (x)) == SUBREG
2425 && REG_P (SUBREG_REG (SET_SRC (x)))))
2426 && GET_MODE (var) == promoted_mode
2427 && x == single_set (insn))
2431 if (GET_CODE (SET_DEST (x)) == SUBREG)
2432 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn,
2435 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2437 if (recog_memoized (insn) >= 0)
2440 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2441 if (NEXT_INSN (pat) != NULL_RTX)
2443 last = emit_insn_before (pat, insn);
2445 /* INSN might have REG_RETVAL or other important notes, so
2446 we need to store the pattern of the last insn in the
2447 sequence into INSN similarly to the normal case. LAST
2448 should not have REG_NOTES, but we allow them if INSN has
2450 if (REG_NOTES (last) && REG_NOTES (insn))
2452 if (REG_NOTES (last))
2453 REG_NOTES (insn) = REG_NOTES (last);
2454 PATTERN (insn) = PATTERN (last);
2459 PATTERN (insn) = PATTERN (pat);
2464 /* Otherwise, storing into VAR must be handled specially
2465 by storing into a temporary and copying that into VAR
2466 with a new insn after this one. Note that this case
2467 will be used when storing into a promoted scalar since
2468 the insn will now have different modes on the input
2469 and output and hence will be invalid (except for the case
2470 of setting it to a constant, which does not need any
2471 change if it is valid). We generate extra code in that case,
2472 but combine.c will eliminate it. */
2477 rtx fixeddest = SET_DEST (x);
2478 enum machine_mode temp_mode;
2480 /* STRICT_LOW_PART can be discarded, around a MEM. */
2481 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2482 fixeddest = XEXP (fixeddest, 0);
2483 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2484 if (GET_CODE (fixeddest) == SUBREG)
2486 fixeddest = fixup_memory_subreg (fixeddest, insn,
2488 temp_mode = GET_MODE (fixeddest);
2492 fixeddest = fixup_stack_1 (fixeddest, insn);
2493 temp_mode = promoted_mode;
2496 temp = gen_reg_rtx (temp_mode);
2498 emit_insn_after (gen_move_insn (fixeddest,
2499 gen_lowpart (GET_MODE (fixeddest),
2503 SET_DEST (x) = temp;
2511 /* Nothing special about this RTX; fix its operands. */
2513 fmt = GET_RTX_FORMAT (code);
2514 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2517 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements,
2519 else if (fmt[i] == 'E')
2522 for (j = 0; j < XVECLEN (x, i); j++)
2523 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2524 insn, replacements, no_share);
2529 /* Previously, X had the form (SUBREG:m1 (REG:PROMOTED_MODE ...)).
2530 The REG was placed on the stack, so X now has the form (SUBREG:m1
2533 Return an rtx (MEM:m1 newaddr) which is equivalent. If any insns
2534 must be emitted to compute NEWADDR, put them before INSN.
2536 UNCRITICAL nonzero means accept paradoxical subregs.
2537 This is used for subregs found inside REG_NOTES. */
2540 fixup_memory_subreg (rtx x, rtx insn, enum machine_mode promoted_mode, int uncritical)
2543 rtx mem = SUBREG_REG (x);
2544 rtx addr = XEXP (mem, 0);
2545 enum machine_mode mode = GET_MODE (x);
2548 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2549 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (mem)) && ! uncritical)
2552 offset = SUBREG_BYTE (x);
2553 if (BYTES_BIG_ENDIAN)
2554 /* If the PROMOTED_MODE is wider than the mode of the MEM, adjust
2555 the offset so that it points to the right location within the
2557 offset -= (GET_MODE_SIZE (promoted_mode) - GET_MODE_SIZE (GET_MODE (mem)));
2559 if (!flag_force_addr
2560 && memory_address_p (mode, plus_constant (addr, offset)))
2561 /* Shortcut if no insns need be emitted. */
2562 return adjust_address (mem, mode, offset);
2565 result = adjust_address (mem, mode, offset);
2569 emit_insn_before (seq, insn);
2573 /* Do fixup_memory_subreg on all (SUBREG (VAR) ...) contained in X.
2574 VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
2575 Replace subexpressions of X in place.
2576 If X itself is a (SUBREG (VAR) ...), return the replacement expression.
2577 Otherwise return X, with its contents possibly altered.
2579 INSN and UNCRITICAL are as for fixup_memory_subreg. */
2582 walk_fixup_memory_subreg (rtx x, rtx insn, rtx var,
2583 enum machine_mode promoted_mode, int uncritical)
2592 code = GET_CODE (x);
2594 if (code == SUBREG && SUBREG_REG (x) == var)
2595 return fixup_memory_subreg (x, insn, promoted_mode, uncritical);
2597 /* Nothing special about this RTX; fix its operands. */
2599 fmt = GET_RTX_FORMAT (code);
2600 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2603 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn, var,
2604 promoted_mode, uncritical);
2605 else if (fmt[i] == 'E')
2608 for (j = 0; j < XVECLEN (x, i); j++)
2610 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn, var,
2611 promoted_mode, uncritical);
2617 /* For each memory ref within X, if it refers to a stack slot
2618 with an out of range displacement, put the address in a temp register
2619 (emitting new insns before INSN to load these registers)
2620 and alter the memory ref to use that register.
2621 Replace each such MEM rtx with a copy, to avoid clobberage. */
2624 fixup_stack_1 (rtx x, rtx insn)
2627 RTX_CODE code = GET_CODE (x);
2632 rtx ad = XEXP (x, 0);
2633 /* If we have address of a stack slot but it's not valid
2634 (displacement is too large), compute the sum in a register. */
2635 if (GET_CODE (ad) == PLUS
2636 && REG_P (XEXP (ad, 0))
2637 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2638 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2639 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2640 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2641 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2643 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2644 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2645 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2646 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2649 if (memory_address_p (GET_MODE (x), ad))
2653 temp = copy_to_reg (ad);
2656 emit_insn_before (seq, insn);
2657 return replace_equiv_address (x, temp);
2662 fmt = GET_RTX_FORMAT (code);
2663 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2666 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2667 else if (fmt[i] == 'E')
2670 for (j = 0; j < XVECLEN (x, i); j++)
2671 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2677 /* Optimization: a bit-field instruction whose field
2678 happens to be a byte or halfword in memory
2679 can be changed to a move instruction.
2681 We call here when INSN is an insn to examine or store into a bit-field.
2682 BODY is the SET-rtx to be altered.
2684 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2685 (Currently this is called only from function.c, and EQUIV_MEM
2689 optimize_bit_field (rtx body, rtx insn, rtx *equiv_mem)
2694 enum machine_mode mode;
2696 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2697 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2698 bitfield = SET_DEST (body), destflag = 1;
2700 bitfield = SET_SRC (body), destflag = 0;
2702 /* First check that the field being stored has constant size and position
2703 and is in fact a byte or halfword suitably aligned. */
2705 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2706 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2707 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2709 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2713 /* Now check that the containing word is memory, not a register,
2714 and that it is safe to change the machine mode. */
2716 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2717 memref = XEXP (bitfield, 0);
2718 else if (REG_P (XEXP (bitfield, 0))
2720 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2721 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2722 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2723 memref = SUBREG_REG (XEXP (bitfield, 0));
2724 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2726 && REG_P (SUBREG_REG (XEXP (bitfield, 0))))
2727 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2730 && ! mode_dependent_address_p (XEXP (memref, 0))
2731 && ! MEM_VOLATILE_P (memref))
2733 /* Now adjust the address, first for any subreg'ing
2734 that we are now getting rid of,
2735 and then for which byte of the word is wanted. */
2737 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2740 /* Adjust OFFSET to count bits from low-address byte. */
2741 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2742 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2743 - offset - INTVAL (XEXP (bitfield, 1)));
2745 /* Adjust OFFSET to count bytes from low-address byte. */
2746 offset /= BITS_PER_UNIT;
2747 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2749 offset += (SUBREG_BYTE (XEXP (bitfield, 0))
2750 / UNITS_PER_WORD) * UNITS_PER_WORD;
2751 if (BYTES_BIG_ENDIAN)
2752 offset -= (MIN (UNITS_PER_WORD,
2753 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2754 - MIN (UNITS_PER_WORD,
2755 GET_MODE_SIZE (GET_MODE (memref))));
2759 memref = adjust_address (memref, mode, offset);
2760 insns = get_insns ();
2762 emit_insn_before (insns, insn);
2764 /* Store this memory reference where
2765 we found the bit field reference. */
2769 validate_change (insn, &SET_DEST (body), memref, 1);
2770 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2772 rtx src = SET_SRC (body);
2773 while (GET_CODE (src) == SUBREG
2774 && SUBREG_BYTE (src) == 0)
2775 src = SUBREG_REG (src);
2776 if (GET_MODE (src) != GET_MODE (memref))
2777 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2778 validate_change (insn, &SET_SRC (body), src, 1);
2780 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2781 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2782 /* This shouldn't happen because anything that didn't have
2783 one of these modes should have got converted explicitly
2784 and then referenced through a subreg.
2785 This is so because the original bit-field was
2786 handled by agg_mode and so its tree structure had
2787 the same mode that memref now has. */
2792 rtx dest = SET_DEST (body);
2794 while (GET_CODE (dest) == SUBREG
2795 && SUBREG_BYTE (dest) == 0
2796 && (GET_MODE_CLASS (GET_MODE (dest))
2797 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2798 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2800 dest = SUBREG_REG (dest);
2802 validate_change (insn, &SET_DEST (body), dest, 1);
2804 if (GET_MODE (dest) == GET_MODE (memref))
2805 validate_change (insn, &SET_SRC (body), memref, 1);
2808 /* Convert the mem ref to the destination mode. */
2809 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2812 convert_move (newreg, memref,
2813 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2817 validate_change (insn, &SET_SRC (body), newreg, 1);
2821 /* See if we can convert this extraction or insertion into
2822 a simple move insn. We might not be able to do so if this
2823 was, for example, part of a PARALLEL.
2825 If we succeed, write out any needed conversions. If we fail,
2826 it is hard to guess why we failed, so don't do anything
2827 special; just let the optimization be suppressed. */
2829 if (apply_change_group () && seq)
2830 emit_insn_before (seq, insn);
2835 /* These routines are responsible for converting virtual register references
2836 to the actual hard register references once RTL generation is complete.
2838 The following four variables are used for communication between the
2839 routines. They contain the offsets of the virtual registers from their
2840 respective hard registers. */
2842 static int in_arg_offset;
2843 static int var_offset;
2844 static int dynamic_offset;
2845 static int out_arg_offset;
2846 static int cfa_offset;
2848 /* In most machines, the stack pointer register is equivalent to the bottom
2851 #ifndef STACK_POINTER_OFFSET
2852 #define STACK_POINTER_OFFSET 0
2855 /* If not defined, pick an appropriate default for the offset of dynamically
2856 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2857 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2859 #ifndef STACK_DYNAMIC_OFFSET
2861 /* The bottom of the stack points to the actual arguments. If
2862 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2863 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2864 stack space for register parameters is not pushed by the caller, but
2865 rather part of the fixed stack areas and hence not included in
2866 `current_function_outgoing_args_size'. Nevertheless, we must allow
2867 for it when allocating stack dynamic objects. */
2869 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2870 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2871 ((ACCUMULATE_OUTGOING_ARGS \
2872 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2873 + (STACK_POINTER_OFFSET)) \
2876 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2877 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2878 + (STACK_POINTER_OFFSET))
2882 /* On most machines, the CFA coincides with the first incoming parm. */
2884 #ifndef ARG_POINTER_CFA_OFFSET
2885 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2888 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just
2889 had its address taken. DECL is the decl or SAVE_EXPR for the
2890 object stored in the register, for later use if we do need to force
2891 REG into the stack. REG is overwritten by the MEM like in
2892 put_reg_into_stack. RESCAN is true if previously emitted
2893 instructions must be rescanned and modified now that the REG has
2894 been transformed. */
2897 gen_mem_addressof (rtx reg, tree decl, int rescan)
2899 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2902 /* Calculate this before we start messing with decl's RTL. */
2903 HOST_WIDE_INT set = decl ? get_alias_set (decl) : 0;
2905 /* If the original REG was a user-variable, then so is the REG whose
2906 address is being taken. Likewise for unchanging. */
2907 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2908 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2910 PUT_CODE (reg, MEM);
2911 MEM_VOLATILE_P (reg) = 0;
2912 MEM_ATTRS (reg) = 0;
2917 tree type = TREE_TYPE (decl);
2918 enum machine_mode decl_mode
2919 = (DECL_P (decl) ? DECL_MODE (decl) : TYPE_MODE (TREE_TYPE (decl)));
2920 rtx decl_rtl = (TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl)
2921 : DECL_RTL_IF_SET (decl));
2923 PUT_MODE (reg, decl_mode);
2925 /* Clear DECL_RTL momentarily so functions below will work
2926 properly, then set it again. */
2927 if (DECL_P (decl) && decl_rtl == reg)
2928 SET_DECL_RTL (decl, 0);
2930 set_mem_attributes (reg, decl, 1);
2931 set_mem_alias_set (reg, set);
2933 if (DECL_P (decl) && decl_rtl == reg)
2934 SET_DECL_RTL (decl, reg);
2937 && (TREE_USED (decl) || (DECL_P (decl) && DECL_INITIAL (decl) != 0)))
2938 fixup_var_refs (reg, GET_MODE (reg), TYPE_UNSIGNED (type), reg, 0);
2942 /* This can only happen during reload. Clear the same flag bits as
2944 RTX_UNCHANGING_P (reg) = 0;
2945 MEM_IN_STRUCT_P (reg) = 0;
2946 MEM_SCALAR_P (reg) = 0;
2948 fixup_var_refs (reg, GET_MODE (reg), 0, reg, 0);
2954 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2957 flush_addressof (tree decl)
2959 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2960 && DECL_RTL (decl) != 0
2961 && GET_CODE (DECL_RTL (decl)) == MEM
2962 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2963 && REG_P (XEXP (XEXP (DECL_RTL (decl), 0), 0)))
2964 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2967 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2970 put_addressof_into_stack (rtx r, htab_t ht)
2973 bool volatile_p, used_p;
2975 rtx reg = XEXP (r, 0);
2980 decl = ADDRESSOF_DECL (r);
2983 type = TREE_TYPE (decl);
2984 volatile_p = (TREE_CODE (decl) != SAVE_EXPR
2985 && TREE_THIS_VOLATILE (decl));
2986 used_p = (TREE_USED (decl)
2987 || (DECL_P (decl) && DECL_INITIAL (decl) != 0));
2996 put_reg_into_stack (0, reg, type, GET_MODE (reg), ADDRESSOF_REGNO (r),
2997 volatile_p, used_p, false, ht);
3000 /* List of replacements made below in purge_addressof_1 when creating
3001 bitfield insertions. */
3002 static rtx purge_bitfield_addressof_replacements;
3004 /* List of replacements made below in purge_addressof_1 for patterns
3005 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
3006 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
3007 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
3008 enough in complex cases, e.g. when some field values can be
3009 extracted by usage MEM with narrower mode. */
3010 static rtx purge_addressof_replacements;
3012 /* Helper function for purge_addressof. See if the rtx expression at *LOC
3013 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
3014 the stack. If the function returns FALSE then the replacement could not
3015 be made. If MAY_POSTPONE is true and we would not put the addressof
3016 to stack, postpone processing of the insn. */
3019 purge_addressof_1 (rtx *loc, rtx insn, int force, int store, int may_postpone,
3027 bool libcall = false;
3029 /* Re-start here to avoid recursion in common cases. */
3036 /* Is this a libcall? */
3038 libcall = REG_NOTE_KIND (*loc) == REG_RETVAL;
3040 code = GET_CODE (x);
3042 /* If we don't return in any of the cases below, we will recurse inside
3043 the RTX, which will normally result in any ADDRESSOF being forced into
3047 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1,
3049 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0,
3053 else if (code == ADDRESSOF)
3057 if (GET_CODE (XEXP (x, 0)) != MEM)
3058 put_addressof_into_stack (x, ht);
3060 /* We must create a copy of the rtx because it was created by
3061 overwriting a REG rtx which is always shared. */
3062 sub = copy_rtx (XEXP (XEXP (x, 0), 0));
3063 if (validate_change (insn, loc, sub, 0)
3064 || validate_replace_rtx (x, sub, insn))
3069 /* If SUB is a hard or virtual register, try it as a pseudo-register.
3070 Otherwise, perhaps SUB is an expression, so generate code to compute
3072 if (REG_P (sub) && REGNO (sub) <= LAST_VIRTUAL_REGISTER)
3073 sub = copy_to_reg (sub);
3075 sub = force_operand (sub, NULL_RTX);
3077 if (! validate_change (insn, loc, sub, 0)
3078 && ! validate_replace_rtx (x, sub, insn))
3081 insns = get_insns ();
3083 emit_insn_before (insns, insn);
3087 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
3089 rtx sub = XEXP (XEXP (x, 0), 0);
3091 if (GET_CODE (sub) == MEM)
3092 sub = adjust_address_nv (sub, GET_MODE (x), 0);
3093 else if (REG_P (sub)
3094 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
3096 else if (REG_P (sub) && GET_MODE (x) != GET_MODE (sub))
3098 int size_x, size_sub;
3102 /* Postpone for now, so that we do not emit bitfield arithmetics
3103 unless there is some benefit from it. */
3104 if (!postponed_insns || XEXP (postponed_insns, 0) != insn)
3105 postponed_insns = alloc_INSN_LIST (insn, postponed_insns);
3111 /* When processing REG_NOTES look at the list of
3112 replacements done on the insn to find the register that X
3116 for (tem = purge_bitfield_addressof_replacements;
3118 tem = XEXP (XEXP (tem, 1), 1))
3119 if (rtx_equal_p (x, XEXP (tem, 0)))
3121 *loc = XEXP (XEXP (tem, 1), 0);
3125 /* See comment for purge_addressof_replacements. */
3126 for (tem = purge_addressof_replacements;
3128 tem = XEXP (XEXP (tem, 1), 1))
3129 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3131 rtx z = XEXP (XEXP (tem, 1), 0);
3133 if (GET_MODE (x) == GET_MODE (z)
3134 || (!REG_P (XEXP (XEXP (tem, 1), 0))
3135 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
3138 /* It can happen that the note may speak of things
3139 in a wider (or just different) mode than the
3140 code did. This is especially true of
3143 if (GET_CODE (z) == SUBREG && SUBREG_BYTE (z) == 0)
3146 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3147 && (GET_MODE_SIZE (GET_MODE (x))
3148 > GET_MODE_SIZE (GET_MODE (z))))
3150 /* This can occur as a result in invalid
3151 pointer casts, e.g. float f; ...
3152 *(long long int *)&f.
3153 ??? We could emit a warning here, but
3154 without a line number that wouldn't be
3156 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
3159 z = gen_lowpart (GET_MODE (x), z);
3165 /* When we are processing the REG_NOTES of the last instruction
3166 of a libcall, there will be typically no replacements
3167 for that insn; the replacements happened before, piecemeal
3168 fashion. OTOH we are not interested in the details of
3169 this for the REG_EQUAL note, we want to know the big picture,
3170 which can be succinctly described with a simple SUBREG.
3171 Note that removing the REG_EQUAL note is not an option
3172 on the last insn of a libcall, so we must do a replacement. */
3174 /* In compile/990107-1.c:7 compiled at -O1 -m1 for sh-elf,
3176 (mem:DI (addressof:SI (reg/v:DF 160) 159 0x401c8510)
3177 [0 S8 A32]), which can be expressed with a simple
3179 if ((GET_MODE_SIZE (GET_MODE (x))
3180 <= GET_MODE_SIZE (GET_MODE (sub)))
3181 /* Again, invalid pointer casts (as in
3182 compile/990203-1.c) can require paradoxical
3184 || (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3185 && (GET_MODE_SIZE (GET_MODE (x))
3186 > GET_MODE_SIZE (GET_MODE (sub)))
3189 *loc = gen_rtx_SUBREG (GET_MODE (x), sub, 0);
3192 /* ??? Are there other cases we should handle? */
3194 /* Sometimes we may not be able to find the replacement. For
3195 example when the original insn was a MEM in a wider mode,
3196 and the note is part of a sign extension of a narrowed
3197 version of that MEM. Gcc testcase compile/990829-1.c can
3198 generate an example of this situation. Rather than complain
3199 we return false, which will prompt our caller to remove the
3204 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3205 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3207 /* Do not frob unchanging MEMs. If a later reference forces the
3208 pseudo to the stack, we can wind up with multiple writes to
3209 an unchanging memory, which is invalid. */
3210 if (RTX_UNCHANGING_P (x) && size_x != size_sub)
3213 /* Don't even consider working with paradoxical subregs,
3214 or the moral equivalent seen here. */
3215 else if (size_x <= size_sub
3216 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3218 /* Do a bitfield insertion to mirror what would happen
3225 rtx p = PREV_INSN (insn);
3228 val = gen_reg_rtx (GET_MODE (x));
3229 if (! validate_change (insn, loc, val, 0))
3231 /* Discard the current sequence and put the
3232 ADDRESSOF on stack. */
3238 emit_insn_before (seq, insn);
3239 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3243 store_bit_field (sub, size_x, 0, GET_MODE (x),
3244 val, GET_MODE_SIZE (GET_MODE (sub)));
3246 /* Make sure to unshare any shared rtl that store_bit_field
3247 might have created. */
3248 unshare_all_rtl_again (get_insns ());
3252 p = emit_insn_after (seq, insn);
3253 if (NEXT_INSN (insn))
3254 compute_insns_for_mem (NEXT_INSN (insn),
3255 p ? NEXT_INSN (p) : NULL_RTX,
3260 rtx p = PREV_INSN (insn);
3263 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3264 GET_MODE (x), GET_MODE (x),
3265 GET_MODE_SIZE (GET_MODE (sub)));
3267 if (! validate_change (insn, loc, val, 0))
3269 /* Discard the current sequence and put the
3270 ADDRESSOF on stack. */
3277 emit_insn_before (seq, insn);
3278 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3282 /* Remember the replacement so that the same one can be done
3283 on the REG_NOTES. */
3284 purge_bitfield_addressof_replacements
3285 = gen_rtx_EXPR_LIST (VOIDmode, x,
3288 purge_bitfield_addressof_replacements));
3290 /* We replaced with a reg -- all done. */
3295 else if (validate_change (insn, loc, sub, 0))
3297 /* Remember the replacement so that the same one can be done
3298 on the REG_NOTES. */
3299 if (REG_P (sub) || GET_CODE (sub) == SUBREG)
3303 for (tem = purge_addressof_replacements;
3305 tem = XEXP (XEXP (tem, 1), 1))
3306 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3308 XEXP (XEXP (tem, 1), 0) = sub;
3311 purge_addressof_replacements
3312 = gen_rtx_EXPR_LIST (VOIDmode, XEXP (x, 0),
3313 gen_rtx_EXPR_LIST (VOIDmode, sub,
3314 purge_addressof_replacements));
3322 /* Scan all subexpressions. */
3323 fmt = GET_RTX_FORMAT (code);
3324 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3327 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0,
3329 else if (*fmt == 'E')
3330 for (j = 0; j < XVECLEN (x, i); j++)
3331 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0,
3338 /* Return a hash value for K, a REG. */
3341 insns_for_mem_hash (const void *k)
3343 /* Use the address of the key for the hash value. */
3344 struct insns_for_mem_entry *m = (struct insns_for_mem_entry *) k;
3345 return htab_hash_pointer (m->key);
3348 /* Return nonzero if K1 and K2 (two REGs) are the same. */
3351 insns_for_mem_comp (const void *k1, const void *k2)
3353 struct insns_for_mem_entry *m1 = (struct insns_for_mem_entry *) k1;
3354 struct insns_for_mem_entry *m2 = (struct insns_for_mem_entry *) k2;
3355 return m1->key == m2->key;
3358 struct insns_for_mem_walk_info
3360 /* The hash table that we are using to record which INSNs use which
3364 /* The INSN we are currently processing. */
3367 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3368 to find the insns that use the REGs in the ADDRESSOFs. */
3372 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3373 that might be used in an ADDRESSOF expression, record this INSN in
3374 the hash table given by DATA (which is really a pointer to an
3375 insns_for_mem_walk_info structure). */
3378 insns_for_mem_walk (rtx *r, void *data)
3380 struct insns_for_mem_walk_info *ifmwi
3381 = (struct insns_for_mem_walk_info *) data;
3382 struct insns_for_mem_entry tmp;
3383 tmp.insns = NULL_RTX;
3385 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3386 && REG_P (XEXP (*r, 0)))
3389 tmp.key = XEXP (*r, 0);
3390 e = htab_find_slot (ifmwi->ht, &tmp, INSERT);
3393 *e = ggc_alloc (sizeof (tmp));
3394 memcpy (*e, &tmp, sizeof (tmp));
3397 else if (ifmwi->pass == 1 && *r && REG_P (*r))
3399 struct insns_for_mem_entry *ifme;
3401 ifme = htab_find (ifmwi->ht, &tmp);
3403 /* If we have not already recorded this INSN, do so now. Since
3404 we process the INSNs in order, we know that if we have
3405 recorded it it must be at the front of the list. */
3406 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3407 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3414 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3415 which REGs in HT. */
3418 compute_insns_for_mem (rtx insns, rtx last_insn, htab_t ht)
3421 struct insns_for_mem_walk_info ifmwi;
3424 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3425 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3429 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3433 /* Helper function for purge_addressof called through for_each_rtx.
3434 Returns true iff the rtl is an ADDRESSOF. */
3437 is_addressof (rtx *rtl, void *data ATTRIBUTE_UNUSED)
3439 return GET_CODE (*rtl) == ADDRESSOF;
3442 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3443 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3447 purge_addressof (rtx insns)
3452 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3453 requires a fixup pass over the instruction stream to correct
3454 INSNs that depended on the REG being a REG, and not a MEM. But,
3455 these fixup passes are slow. Furthermore, most MEMs are not
3456 mentioned in very many instructions. So, we speed up the process
3457 by pre-calculating which REGs occur in which INSNs; that allows
3458 us to perform the fixup passes much more quickly. */
3459 ht = htab_create_ggc (1000, insns_for_mem_hash, insns_for_mem_comp, NULL);
3460 compute_insns_for_mem (insns, NULL_RTX, ht);
3462 postponed_insns = NULL;
3464 for (insn = insns; insn; insn = NEXT_INSN (insn))
3467 if (! purge_addressof_1 (&PATTERN (insn), insn,
3468 asm_noperands (PATTERN (insn)) > 0, 0, 1, ht))
3469 /* If we could not replace the ADDRESSOFs in the insn,
3470 something is wrong. */
3473 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, 0, ht))
3475 /* If we could not replace the ADDRESSOFs in the insn's notes,
3476 we can just remove the offending notes instead. */
3479 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3481 /* If we find a REG_RETVAL note then the insn is a libcall.
3482 Such insns must have REG_EQUAL notes as well, in order
3483 for later passes of the compiler to work. So it is not
3484 safe to delete the notes here, and instead we abort. */
3485 if (REG_NOTE_KIND (note) == REG_RETVAL)
3487 if (for_each_rtx (¬e, is_addressof, NULL))
3488 remove_note (insn, note);
3493 /* Process the postponed insns. */
3494 while (postponed_insns)
3496 insn = XEXP (postponed_insns, 0);
3497 tmp = postponed_insns;
3498 postponed_insns = XEXP (postponed_insns, 1);
3499 free_INSN_LIST_node (tmp);
3501 if (! purge_addressof_1 (&PATTERN (insn), insn,
3502 asm_noperands (PATTERN (insn)) > 0, 0, 0, ht))
3507 purge_bitfield_addressof_replacements = 0;
3508 purge_addressof_replacements = 0;
3510 /* REGs are shared. purge_addressof will destructively replace a REG
3511 with a MEM, which creates shared MEMs.
3513 Unfortunately, the children of put_reg_into_stack assume that MEMs
3514 referring to the same stack slot are shared (fixup_var_refs and
3515 the associated hash table code).
3517 So, we have to do another unsharing pass after we have flushed any
3518 REGs that had their address taken into the stack.
3520 It may be worth tracking whether or not we converted any REGs into
3521 MEMs to avoid this overhead when it is not needed. */
3522 unshare_all_rtl_again (get_insns ());
3525 /* Convert a SET of a hard subreg to a set of the appropriate hard
3526 register. A subroutine of purge_hard_subreg_sets. */
3529 purge_single_hard_subreg_set (rtx pattern)
3531 rtx reg = SET_DEST (pattern);
3532 enum machine_mode mode = GET_MODE (SET_DEST (pattern));
3535 if (GET_CODE (reg) == SUBREG && REG_P (SUBREG_REG (reg))
3536 && REGNO (SUBREG_REG (reg)) < FIRST_PSEUDO_REGISTER)
3538 offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)),
3539 GET_MODE (SUBREG_REG (reg)),
3542 reg = SUBREG_REG (reg);
3546 if (REG_P (reg) && REGNO (reg) < FIRST_PSEUDO_REGISTER)
3548 reg = gen_rtx_REG (mode, REGNO (reg) + offset);
3549 SET_DEST (pattern) = reg;
3553 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The
3554 only such SETs that we expect to see are those left in because
3555 integrate can't handle sets of parts of a return value register.
3557 We don't use alter_subreg because we only want to eliminate subregs
3558 of hard registers. */
3561 purge_hard_subreg_sets (rtx insn)
3563 for (; insn; insn = NEXT_INSN (insn))
3567 rtx pattern = PATTERN (insn);
3568 switch (GET_CODE (pattern))
3571 if (GET_CODE (SET_DEST (pattern)) == SUBREG)
3572 purge_single_hard_subreg_set (pattern);
3577 for (j = XVECLEN (pattern, 0) - 1; j >= 0; j--)
3579 rtx inner_pattern = XVECEXP (pattern, 0, j);
3580 if (GET_CODE (inner_pattern) == SET
3581 && GET_CODE (SET_DEST (inner_pattern)) == SUBREG)
3582 purge_single_hard_subreg_set (inner_pattern);
3593 /* Pass through the INSNS of function FNDECL and convert virtual register
3594 references to hard register references. */
3597 instantiate_virtual_regs (void)
3602 /* Compute the offsets to use for this function. */
3603 in_arg_offset = FIRST_PARM_OFFSET (current_function_decl);
3604 var_offset = STARTING_FRAME_OFFSET;
3605 dynamic_offset = STACK_DYNAMIC_OFFSET (current_function_decl);
3606 out_arg_offset = STACK_POINTER_OFFSET;
3607 cfa_offset = ARG_POINTER_CFA_OFFSET (current_function_decl);
3609 /* Scan all variables and parameters of this function. For each that is
3610 in memory, instantiate all virtual registers if the result is a valid
3611 address. If not, we do it later. That will handle most uses of virtual
3612 regs on many machines. */
3613 instantiate_decls (current_function_decl, 1);
3615 /* Initialize recognition, indicating that volatile is OK. */
3618 /* Scan through all the insns, instantiating every virtual register still
3620 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3621 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3622 || GET_CODE (insn) == CALL_INSN)
3624 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3625 if (INSN_DELETED_P (insn))
3627 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3628 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
3629 if (GET_CODE (insn) == CALL_INSN)
3630 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn),
3633 /* Past this point all ASM statements should match. Verify that
3634 to avoid failures later in the compilation process. */
3635 if (asm_noperands (PATTERN (insn)) >= 0
3636 && ! check_asm_operands (PATTERN (insn)))
3637 instantiate_virtual_regs_lossage (insn);
3640 /* Instantiate the stack slots for the parm registers, for later use in
3641 addressof elimination. */
3642 for (i = 0; i < max_parm_reg; ++i)
3643 if (parm_reg_stack_loc[i])
3644 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3646 /* Now instantiate the remaining register equivalences for debugging info.
3647 These will not be valid addresses. */
3648 instantiate_decls (current_function_decl, 0);
3650 /* Indicate that, from now on, assign_stack_local should use
3651 frame_pointer_rtx. */
3652 virtuals_instantiated = 1;
3655 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3656 all virtual registers in their DECL_RTL's.
3658 If VALID_ONLY, do this only if the resulting address is still valid.
3659 Otherwise, always do it. */
3662 instantiate_decls (tree fndecl, int valid_only)
3666 /* Process all parameters of the function. */
3667 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3669 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3670 HOST_WIDE_INT size_rtl;
3672 instantiate_decl (DECL_RTL (decl), size, valid_only);
3674 /* If the parameter was promoted, then the incoming RTL mode may be
3675 larger than the declared type size. We must use the larger of
3677 size_rtl = GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl)));
3678 size = MAX (size_rtl, size);
3679 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3682 /* Now process all variables defined in the function or its subblocks. */
3683 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3686 /* Subroutine of instantiate_decls: Process all decls in the given
3687 BLOCK node and all its subblocks. */
3690 instantiate_decls_1 (tree let, int valid_only)
3694 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3695 if (DECL_RTL_SET_P (t))
3696 instantiate_decl (DECL_RTL (t),
3697 int_size_in_bytes (TREE_TYPE (t)),
3700 /* Process all subblocks. */
3701 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3702 instantiate_decls_1 (t, valid_only);
3705 /* Subroutine of the preceding procedures: Given RTL representing a
3706 decl and the size of the object, do any instantiation required.
3708 If VALID_ONLY is nonzero, it means that the RTL should only be
3709 changed if the new address is valid. */
3712 instantiate_decl (rtx x, HOST_WIDE_INT size, int valid_only)
3714 enum machine_mode mode;
3717 /* If this is not a MEM, no need to do anything. Similarly if the
3718 address is a constant or a register that is not a virtual register. */
3720 if (x == 0 || GET_CODE (x) != MEM)
3724 if (CONSTANT_P (addr)
3725 || (GET_CODE (addr) == ADDRESSOF && REG_P (XEXP (addr, 0)))
3727 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3728 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3731 /* If we should only do this if the address is valid, copy the address.
3732 We need to do this so we can undo any changes that might make the
3733 address invalid. This copy is unfortunate, but probably can't be
3737 addr = copy_rtx (addr);
3739 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3741 if (valid_only && size >= 0)
3743 unsigned HOST_WIDE_INT decl_size = size;
3745 /* Now verify that the resulting address is valid for every integer or
3746 floating-point mode up to and including SIZE bytes long. We do this
3747 since the object might be accessed in any mode and frame addresses
3750 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3751 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3752 mode = GET_MODE_WIDER_MODE (mode))
3753 if (! memory_address_p (mode, addr))
3756 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3757 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3758 mode = GET_MODE_WIDER_MODE (mode))
3759 if (! memory_address_p (mode, addr))
3763 /* Put back the address now that we have updated it and we either know
3764 it is valid or we don't care whether it is valid. */
3769 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
3770 is a virtual register, return the equivalent hard register and set the
3771 offset indirectly through the pointer. Otherwise, return 0. */
3774 instantiate_new_reg (rtx x, HOST_WIDE_INT *poffset)
3777 HOST_WIDE_INT offset;
3779 if (x == virtual_incoming_args_rtx)
3780 new = arg_pointer_rtx, offset = in_arg_offset;
3781 else if (x == virtual_stack_vars_rtx)
3782 new = frame_pointer_rtx, offset = var_offset;
3783 else if (x == virtual_stack_dynamic_rtx)
3784 new = stack_pointer_rtx, offset = dynamic_offset;
3785 else if (x == virtual_outgoing_args_rtx)
3786 new = stack_pointer_rtx, offset = out_arg_offset;
3787 else if (x == virtual_cfa_rtx)
3788 new = arg_pointer_rtx, offset = cfa_offset;
3797 /* Called when instantiate_virtual_regs has failed to update the instruction.
3798 Usually this means that non-matching instruction has been emit, however for
3799 asm statements it may be the problem in the constraints. */
3801 instantiate_virtual_regs_lossage (rtx insn)
3803 if (asm_noperands (PATTERN (insn)) >= 0)
3805 error_for_asm (insn, "impossible constraint in `asm'");
3811 /* Given a pointer to a piece of rtx and an optional pointer to the
3812 containing object, instantiate any virtual registers present in it.
3814 If EXTRA_INSNS, we always do the replacement and generate
3815 any extra insns before OBJECT. If it zero, we do nothing if replacement
3818 Return 1 if we either had nothing to do or if we were able to do the
3819 needed replacement. Return 0 otherwise; we only return zero if
3820 EXTRA_INSNS is zero.
3822 We first try some simple transformations to avoid the creation of extra
3826 instantiate_virtual_regs_1 (rtx *loc, rtx object, int extra_insns)
3831 HOST_WIDE_INT offset = 0;
3837 /* Re-start here to avoid recursion in common cases. */
3844 /* We may have detected and deleted invalid asm statements. */
3845 if (object && INSN_P (object) && INSN_DELETED_P (object))
3848 code = GET_CODE (x);
3850 /* Check for some special cases. */
3868 /* We are allowed to set the virtual registers. This means that
3869 the actual register should receive the source minus the
3870 appropriate offset. This is used, for example, in the handling
3871 of non-local gotos. */
3872 if ((new = instantiate_new_reg (SET_DEST (x), &offset)) != 0)
3874 rtx src = SET_SRC (x);
3876 /* We are setting the register, not using it, so the relevant
3877 offset is the negative of the offset to use were we using
3880 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3882 /* The only valid sources here are PLUS or REG. Just do
3883 the simplest possible thing to handle them. */
3884 if (!REG_P (src) && GET_CODE (src) != PLUS)
3886 instantiate_virtual_regs_lossage (object);
3892 temp = force_operand (src, NULL_RTX);
3895 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3899 emit_insn_before (seq, object);
3902 if (! validate_change (object, &SET_SRC (x), temp, 0)
3904 instantiate_virtual_regs_lossage (object);
3909 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3914 /* Handle special case of virtual register plus constant. */
3915 if (CONSTANT_P (XEXP (x, 1)))
3917 rtx old, new_offset;
3919 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3920 if (GET_CODE (XEXP (x, 0)) == PLUS)
3922 if ((new = instantiate_new_reg (XEXP (XEXP (x, 0), 0), &offset)))
3924 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3926 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3935 #ifdef POINTERS_EXTEND_UNSIGNED
3936 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
3937 we can commute the PLUS and SUBREG because pointers into the
3938 frame are well-behaved. */
3939 else if (GET_CODE (XEXP (x, 0)) == SUBREG && GET_MODE (x) == ptr_mode
3940 && GET_CODE (XEXP (x, 1)) == CONST_INT
3942 = instantiate_new_reg (SUBREG_REG (XEXP (x, 0)),
3944 && validate_change (object, loc,
3945 plus_constant (gen_lowpart (ptr_mode,
3948 + INTVAL (XEXP (x, 1))),
3952 else if ((new = instantiate_new_reg (XEXP (x, 0), &offset)) == 0)
3954 /* We know the second operand is a constant. Unless the
3955 first operand is a REG (which has been already checked),
3956 it needs to be checked. */
3957 if (!REG_P (XEXP (x, 0)))
3965 new_offset = plus_constant (XEXP (x, 1), offset);
3967 /* If the new constant is zero, try to replace the sum with just
3969 if (new_offset == const0_rtx
3970 && validate_change (object, loc, new, 0))
3973 /* Next try to replace the register and new offset.
3974 There are two changes to validate here and we can't assume that
3975 in the case of old offset equals new just changing the register
3976 will yield a valid insn. In the interests of a little efficiency,
3977 however, we only call validate change once (we don't queue up the
3978 changes and then call apply_change_group). */
3982 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3983 : (XEXP (x, 0) = new,
3984 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3992 /* Otherwise copy the new constant into a register and replace
3993 constant with that register. */
3994 temp = gen_reg_rtx (Pmode);
3996 if (validate_change (object, &XEXP (x, 1), temp, 0))
3997 emit_insn_before (gen_move_insn (temp, new_offset), object);
4000 /* If that didn't work, replace this expression with a
4001 register containing the sum. */
4004 new = gen_rtx_PLUS (Pmode, new, new_offset);
4007 temp = force_operand (new, NULL_RTX);
4011 emit_insn_before (seq, object);
4012 if (! validate_change (object, loc, temp, 0)
4013 && ! validate_replace_rtx (x, temp, object))
4015 instantiate_virtual_regs_lossage (object);
4024 /* Fall through to generic two-operand expression case. */
4030 case DIV: case UDIV:
4031 case MOD: case UMOD:
4032 case AND: case IOR: case XOR:
4033 case ROTATERT: case ROTATE:
4034 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
4036 case GE: case GT: case GEU: case GTU:
4037 case LE: case LT: case LEU: case LTU:
4038 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
4039 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
4044 /* Most cases of MEM that convert to valid addresses have already been
4045 handled by our scan of decls. The only special handling we
4046 need here is to make a copy of the rtx to ensure it isn't being
4047 shared if we have to change it to a pseudo.
4049 If the rtx is a simple reference to an address via a virtual register,
4050 it can potentially be shared. In such cases, first try to make it
4051 a valid address, which can also be shared. Otherwise, copy it and
4054 First check for common cases that need no processing. These are
4055 usually due to instantiation already being done on a previous instance
4059 if (CONSTANT_ADDRESS_P (temp)
4060 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
4061 || temp == arg_pointer_rtx
4063 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
4064 || temp == hard_frame_pointer_rtx
4066 || temp == frame_pointer_rtx)
4069 if (GET_CODE (temp) == PLUS
4070 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
4071 && (XEXP (temp, 0) == frame_pointer_rtx
4072 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
4073 || XEXP (temp, 0) == hard_frame_pointer_rtx
4075 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
4076 || XEXP (temp, 0) == arg_pointer_rtx
4081 if (temp == virtual_stack_vars_rtx
4082 || temp == virtual_incoming_args_rtx
4083 || (GET_CODE (temp) == PLUS
4084 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
4085 && (XEXP (temp, 0) == virtual_stack_vars_rtx
4086 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
4088 /* This MEM may be shared. If the substitution can be done without
4089 the need to generate new pseudos, we want to do it in place
4090 so all copies of the shared rtx benefit. The call below will
4091 only make substitutions if the resulting address is still
4094 Note that we cannot pass X as the object in the recursive call
4095 since the insn being processed may not allow all valid
4096 addresses. However, if we were not passed on object, we can
4097 only modify X without copying it if X will have a valid
4100 ??? Also note that this can still lose if OBJECT is an insn that
4101 has less restrictions on an address that some other insn.
4102 In that case, we will modify the shared address. This case
4103 doesn't seem very likely, though. One case where this could
4104 happen is in the case of a USE or CLOBBER reference, but we
4105 take care of that below. */
4107 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
4108 object ? object : x, 0))
4111 /* Otherwise make a copy and process that copy. We copy the entire
4112 RTL expression since it might be a PLUS which could also be
4114 *loc = x = copy_rtx (x);
4117 /* Fall through to generic unary operation case. */
4120 case STRICT_LOW_PART:
4122 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
4123 case SIGN_EXTEND: case ZERO_EXTEND:
4124 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
4125 case FLOAT: case FIX:
4126 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
4131 case POPCOUNT: case PARITY:
4132 /* These case either have just one operand or we know that we need not
4133 check the rest of the operands. */
4139 /* If the operand is a MEM, see if the change is a valid MEM. If not,
4140 go ahead and make the invalid one, but do it to a copy. For a REG,
4141 just make the recursive call, since there's no chance of a problem. */
4143 if ((GET_CODE (XEXP (x, 0)) == MEM
4144 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
4146 || (REG_P (XEXP (x, 0))
4147 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
4150 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
4155 /* Try to replace with a PLUS. If that doesn't work, compute the sum
4156 in front of this insn and substitute the temporary. */
4157 if ((new = instantiate_new_reg (x, &offset)) != 0)
4159 temp = plus_constant (new, offset);
4160 if (!validate_change (object, loc, temp, 0))
4166 temp = force_operand (temp, NULL_RTX);
4170 emit_insn_before (seq, object);
4171 if (! validate_change (object, loc, temp, 0)
4172 && ! validate_replace_rtx (x, temp, object))
4173 instantiate_virtual_regs_lossage (object);
4180 if (REG_P (XEXP (x, 0)))
4183 else if (GET_CODE (XEXP (x, 0)) == MEM)
4185 /* If we have a (addressof (mem ..)), do any instantiation inside
4186 since we know we'll be making the inside valid when we finally
4187 remove the ADDRESSOF. */
4188 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
4197 /* Scan all subexpressions. */
4198 fmt = GET_RTX_FORMAT (code);
4199 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
4202 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
4205 else if (*fmt == 'E')
4206 for (j = 0; j < XVECLEN (x, i); j++)
4207 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
4214 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4215 This means a type for which function calls must pass an address to the
4216 function or get an address back from the function.
4217 EXP may be a type node or an expression (whose type is tested). */
4220 aggregate_value_p (tree exp, tree fntype)
4222 int i, regno, nregs;
4225 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4228 switch (TREE_CODE (fntype))
4231 fntype = get_callee_fndecl (fntype);
4232 fntype = fntype ? TREE_TYPE (fntype) : 0;
4235 fntype = TREE_TYPE (fntype);
4240 case IDENTIFIER_NODE:
4244 /* We don't expect other rtl types here. */
4248 if (TREE_CODE (type) == VOID_TYPE)
4250 if (targetm.calls.return_in_memory (type, fntype))
4252 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4253 and thus can't be returned in registers. */
4254 if (TREE_ADDRESSABLE (type))
4256 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4258 /* Make sure we have suitable call-clobbered regs to return
4259 the value in; if not, we must return it in memory. */
4260 reg = hard_function_value (type, 0, 0);
4262 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4267 regno = REGNO (reg);
4268 nregs = hard_regno_nregs[regno][TYPE_MODE (type)];
4269 for (i = 0; i < nregs; i++)
4270 if (! call_used_regs[regno + i])
4275 /* Assign RTL expressions to the function's parameters.
4276 This may involve copying them into registers and using
4277 those registers as the RTL for them. */
4280 assign_parms (tree fndecl)
4283 CUMULATIVE_ARGS args_so_far;
4284 /* Total space needed so far for args on the stack,
4285 given as a constant and a tree-expression. */
4286 struct args_size stack_args_size;
4287 HOST_WIDE_INT extra_pretend_bytes = 0;
4288 tree fntype = TREE_TYPE (fndecl);
4289 tree fnargs = DECL_ARGUMENTS (fndecl), orig_fnargs;
4290 /* This is used for the arg pointer when referring to stack args. */
4291 rtx internal_arg_pointer;
4292 /* This is a dummy PARM_DECL that we used for the function result if
4293 the function returns a structure. */
4294 tree function_result_decl = 0;
4295 int varargs_setup = 0;
4296 int reg_parm_stack_space ATTRIBUTE_UNUSED = 0;
4297 rtx conversion_insns = 0;
4299 /* Nonzero if function takes extra anonymous args.
4300 This means the last named arg must be on the stack
4301 right before the anonymous ones. */
4302 int stdarg = current_function_stdarg;
4304 /* If the reg that the virtual arg pointer will be translated into is
4305 not a fixed reg or is the stack pointer, make a copy of the virtual
4306 arg pointer, and address parms via the copy. The frame pointer is
4307 considered fixed even though it is not marked as such.
4309 The second time through, simply use ap to avoid generating rtx. */
4311 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4312 || ! (fixed_regs[ARG_POINTER_REGNUM]
4313 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4314 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4316 internal_arg_pointer = virtual_incoming_args_rtx;
4317 current_function_internal_arg_pointer = internal_arg_pointer;
4319 stack_args_size.constant = 0;
4320 stack_args_size.var = 0;
4322 /* If struct value address is treated as the first argument, make it so. */
4323 if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
4324 && ! current_function_returns_pcc_struct
4325 && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
4327 tree type = build_pointer_type (TREE_TYPE (fntype));
4329 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4331 DECL_ARG_TYPE (function_result_decl) = type;
4332 TREE_CHAIN (function_result_decl) = fnargs;
4333 fnargs = function_result_decl;
4336 orig_fnargs = fnargs;
4338 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4339 parm_reg_stack_loc = ggc_alloc_cleared (max_parm_reg * sizeof (rtx));
4341 /* If the target wants to split complex arguments into scalars, do so. */
4342 if (targetm.calls.split_complex_arg)
4343 fnargs = split_complex_args (fnargs);
4345 #ifdef REG_PARM_STACK_SPACE
4346 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
4349 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4350 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4352 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, fndecl, -1);
4355 /* We haven't yet found an argument that we must push and pretend the
4357 current_function_pretend_args_size = 0;
4359 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4363 enum machine_mode promoted_mode, passed_mode;
4364 enum machine_mode nominal_mode, promoted_nominal_mode;
4366 struct locate_and_pad_arg_data locate;
4367 int passed_pointer = 0;
4368 int did_conversion = 0;
4369 tree passed_type = DECL_ARG_TYPE (parm);
4370 tree nominal_type = TREE_TYPE (parm);
4371 int last_named = 0, named_arg;
4374 int pretend_bytes = 0;
4375 int loaded_in_reg = 0;
4377 /* Set LAST_NAMED if this is last named arg before last
4383 for (tem = TREE_CHAIN (parm); tem; tem = TREE_CHAIN (tem))
4384 if (DECL_NAME (tem))
4390 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4391 most machines, if this is a varargs/stdarg function, then we treat
4392 the last named arg as if it were anonymous too. */
4393 named_arg = (targetm.calls.strict_argument_naming (&args_so_far)
4396 if (TREE_TYPE (parm) == error_mark_node
4397 /* This can happen after weird syntax errors
4398 or if an enum type is defined among the parms. */
4399 || TREE_CODE (parm) != PARM_DECL
4400 || passed_type == NULL)
4402 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx));
4403 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4404 TREE_USED (parm) = 1;
4408 /* Find mode of arg as it is passed, and mode of arg
4409 as it should be during execution of this function. */
4410 passed_mode = TYPE_MODE (passed_type);
4411 nominal_mode = TYPE_MODE (nominal_type);
4413 /* If the parm's mode is VOID, its value doesn't matter,
4414 and avoid the usual things like emit_move_insn that could crash. */
4415 if (nominal_mode == VOIDmode)
4417 SET_DECL_RTL (parm, const0_rtx);
4418 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4422 /* If the parm is to be passed as a transparent union, use the
4423 type of the first field for the tests below. We have already
4424 verified that the modes are the same. */
4425 if (DECL_TRANSPARENT_UNION (parm)
4426 || (TREE_CODE (passed_type) == UNION_TYPE
4427 && TYPE_TRANSPARENT_UNION (passed_type)))
4428 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4430 /* See if this arg was passed by invisible reference. It is if
4431 it is an object whose size depends on the contents of the
4432 object itself or if the machine requires these objects be passed
4435 if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE (passed_type))
4436 || TREE_ADDRESSABLE (passed_type)
4437 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4438 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4439 passed_type, named_arg)
4443 passed_type = nominal_type = build_pointer_type (passed_type);
4445 passed_mode = nominal_mode = Pmode;
4447 /* See if the frontend wants to pass this by invisible reference. */
4448 else if (passed_type != nominal_type
4449 && POINTER_TYPE_P (passed_type)
4450 && TREE_TYPE (passed_type) == nominal_type)
4452 nominal_type = passed_type;
4454 passed_mode = nominal_mode = Pmode;
4457 promoted_mode = passed_mode;
4459 if (targetm.calls.promote_function_args (TREE_TYPE (fndecl)))
4461 /* Compute the mode in which the arg is actually extended to. */
4462 unsignedp = TYPE_UNSIGNED (passed_type);
4463 promoted_mode = promote_mode (passed_type, promoted_mode,
4467 /* Let machine desc say which reg (if any) the parm arrives in.
4468 0 means it arrives on the stack. */
4469 #ifdef FUNCTION_INCOMING_ARG
4470 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4471 passed_type, named_arg);
4473 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4474 passed_type, named_arg);
4477 if (entry_parm == 0)
4478 promoted_mode = passed_mode;
4480 /* If this is the last named parameter, do any required setup for
4481 varargs or stdargs. We need to know about the case of this being an
4482 addressable type, in which case we skip the registers it
4483 would have arrived in.
4485 For stdargs, LAST_NAMED will be set for two parameters, the one that
4486 is actually the last named, and the dummy parameter. We only
4487 want to do this action once.
4489 Also, indicate when RTL generation is to be suppressed. */
4490 if (last_named && !varargs_setup)
4492 int varargs_pretend_bytes = 0;
4493 targetm.calls.setup_incoming_varargs (&args_so_far, promoted_mode,
4495 &varargs_pretend_bytes, 0);
4498 /* If the back-end has requested extra stack space, record how
4499 much is needed. Do not change pretend_args_size otherwise
4500 since it may be nonzero from an earlier partial argument. */
4501 if (varargs_pretend_bytes > 0)
4502 current_function_pretend_args_size = varargs_pretend_bytes;
4505 /* Determine parm's home in the stack,
4506 in case it arrives in the stack or we should pretend it did.
4508 Compute the stack position and rtx where the argument arrives
4511 There is one complexity here: If this was a parameter that would
4512 have been passed in registers, but wasn't only because it is
4513 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4514 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4515 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4516 0 as it was the previous time. */
4517 in_regs = entry_parm != 0;
4518 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4521 if (!in_regs && !named_arg)
4524 targetm.calls.pretend_outgoing_varargs_named (&args_so_far);
4527 #ifdef FUNCTION_INCOMING_ARG
4528 in_regs = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4530 pretend_named) != 0;
4532 in_regs = FUNCTION_ARG (args_so_far, promoted_mode,
4534 pretend_named) != 0;
4539 /* If this parameter was passed both in registers and in the stack,
4540 use the copy on the stack. */
4541 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4544 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4547 partial = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4548 passed_type, named_arg);
4550 /* The caller might already have allocated stack space
4551 for the register parameters. */
4552 && reg_parm_stack_space == 0)
4554 /* Part of this argument is passed in registers and part
4555 is passed on the stack. Ask the prologue code to extend
4556 the stack part so that we can recreate the full value.
4558 PRETEND_BYTES is the size of the registers we need to store.
4559 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
4560 stack space that the prologue should allocate.
4562 Internally, gcc assumes that the argument pointer is
4563 aligned to STACK_BOUNDARY bits. This is used both for
4564 alignment optimizations (see init_emit) and to locate
4565 arguments that are aligned to more than PARM_BOUNDARY
4566 bits. We must preserve this invariant by rounding
4567 CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to a stack
4570 /* We assume at most one partial arg, and it must be the first
4571 argument on the stack. */
4572 if (extra_pretend_bytes || current_function_pretend_args_size)
4575 pretend_bytes = partial * UNITS_PER_WORD;
4576 current_function_pretend_args_size
4577 = CEIL_ROUND (pretend_bytes, STACK_BYTES);
4579 /* We want to align relative to the actual stack pointer, so
4580 don't include this in the stack size until later. */
4581 extra_pretend_bytes = current_function_pretend_args_size;
4586 memset (&locate, 0, sizeof (locate));
4587 locate_and_pad_parm (promoted_mode, passed_type, in_regs,
4588 entry_parm ? partial : 0, fndecl,
4589 &stack_args_size, &locate);
4590 /* Adjust offsets to include the pretend args. */
4591 locate.slot_offset.constant += extra_pretend_bytes - pretend_bytes;
4592 locate.offset.constant += extra_pretend_bytes - pretend_bytes;
4596 unsigned int align, boundary;
4598 /* If we're passing this arg using a reg, make its stack home
4599 the aligned stack slot. */
4601 offset_rtx = ARGS_SIZE_RTX (locate.slot_offset);
4603 offset_rtx = ARGS_SIZE_RTX (locate.offset);
4605 if (offset_rtx == const0_rtx)
4606 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4608 stack_parm = gen_rtx_MEM (promoted_mode,
4609 gen_rtx_PLUS (Pmode,
4610 internal_arg_pointer,
4613 set_mem_attributes (stack_parm, parm, 1);
4615 boundary = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4618 /* If we're padding upward, we know that the alignment of the slot
4619 is FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
4620 intentionally forcing upward padding. Otherwise we have to come
4621 up with a guess at the alignment based on OFFSET_RTX. */
4622 if (locate.where_pad == upward || entry_parm)
4624 else if (GET_CODE (offset_rtx) == CONST_INT)
4626 align = INTVAL (offset_rtx) * BITS_PER_UNIT | boundary;
4627 align = align & -align;
4630 set_mem_align (stack_parm, align);
4633 set_reg_attrs_for_parm (entry_parm, stack_parm);
4636 /* If this parm was passed part in regs and part in memory,
4637 pretend it arrived entirely in memory
4638 by pushing the register-part onto the stack.
4640 In the special case of a DImode or DFmode that is split,
4641 we could put it together in a pseudoreg directly,
4642 but for now that's not worth bothering with. */
4646 /* Handle calls that pass values in multiple non-contiguous
4647 locations. The Irix 6 ABI has examples of this. */
4648 if (GET_CODE (entry_parm) == PARALLEL)
4649 emit_group_store (validize_mem (stack_parm), entry_parm,
4651 int_size_in_bytes (TREE_TYPE (parm)));
4654 move_block_from_reg (REGNO (entry_parm), validize_mem (stack_parm),
4657 entry_parm = stack_parm;
4660 /* If we didn't decide this parm came in a register,
4661 by default it came on the stack. */
4662 if (entry_parm == 0)
4663 entry_parm = stack_parm;
4665 /* Record permanently how this parm was passed. */
4666 set_decl_incoming_rtl (parm, entry_parm);
4668 /* If there is actually space on the stack for this parm,
4669 count it in stack_args_size; otherwise set stack_parm to 0
4670 to indicate there is no preallocated stack slot for the parm. */
4672 if (entry_parm == stack_parm
4673 || (GET_CODE (entry_parm) == PARALLEL
4674 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4675 #if defined (REG_PARM_STACK_SPACE)
4676 /* On some machines, even if a parm value arrives in a register
4677 there is still an (uninitialized) stack slot allocated
4679 || REG_PARM_STACK_SPACE (fndecl) > 0
4683 stack_args_size.constant += locate.size.constant;
4684 if (locate.size.var)
4685 ADD_PARM_SIZE (stack_args_size, locate.size.var);
4688 /* No stack slot was pushed for this parm. */
4691 /* Update info on where next arg arrives in registers. */
4693 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4694 passed_type, named_arg);
4696 /* If we can't trust the parm stack slot to be aligned enough
4697 for its ultimate type, don't use that slot after entry.
4698 We'll make another stack slot, if we need one. */
4699 if (STRICT_ALIGNMENT && stack_parm
4700 && GET_MODE_ALIGNMENT (nominal_mode) > MEM_ALIGN (stack_parm))
4703 /* If parm was passed in memory, and we need to convert it on entry,
4704 don't store it back in that same slot. */
4705 if (entry_parm == stack_parm
4706 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4709 /* When an argument is passed in multiple locations, we can't
4710 make use of this information, but we can save some copying if
4711 the whole argument is passed in a single register. */
4712 if (GET_CODE (entry_parm) == PARALLEL
4713 && nominal_mode != BLKmode && passed_mode != BLKmode)
4715 int i, len = XVECLEN (entry_parm, 0);
4717 for (i = 0; i < len; i++)
4718 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
4719 && REG_P (XEXP (XVECEXP (entry_parm, 0, i), 0))
4720 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
4722 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
4724 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
4725 set_decl_incoming_rtl (parm, entry_parm);
4730 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4731 in the mode in which it arrives.
4732 STACK_PARM is an RTX for a stack slot where the parameter can live
4733 during the function (in case we want to put it there).
4734 STACK_PARM is 0 if no stack slot was pushed for it.
4736 Now output code if necessary to convert ENTRY_PARM to
4737 the type in which this function declares it,
4738 and store that result in an appropriate place,
4739 which may be a pseudo reg, may be STACK_PARM,
4740 or may be a local stack slot if STACK_PARM is 0.
4742 Set DECL_RTL to that place. */
4744 if (GET_CODE (entry_parm) == PARALLEL && nominal_mode != BLKmode
4745 && XVECLEN (entry_parm, 0) > 1)
4747 /* Reconstitute objects the size of a register or larger using
4748 register operations instead of the stack. */
4749 rtx parmreg = gen_reg_rtx (nominal_mode);
4751 if (REG_P (parmreg))
4753 unsigned int regno = REGNO (parmreg);
4755 emit_group_store (parmreg, entry_parm, TREE_TYPE (parm),
4756 int_size_in_bytes (TREE_TYPE (parm)));
4757 SET_DECL_RTL (parm, parmreg);
4760 if (regno >= max_parm_reg)
4763 int old_max_parm_reg = max_parm_reg;
4765 /* It's slow to expand this one register at a time,
4766 but it's also rare and we need max_parm_reg to be
4767 precisely correct. */
4768 max_parm_reg = regno + 1;
4769 new = ggc_realloc (parm_reg_stack_loc,
4770 max_parm_reg * sizeof (rtx));
4771 memset (new + old_max_parm_reg, 0,
4772 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4773 parm_reg_stack_loc = new;
4774 parm_reg_stack_loc[regno] = stack_parm;
4779 if (nominal_mode == BLKmode
4780 #ifdef BLOCK_REG_PADDING
4781 || (locate.where_pad == (BYTES_BIG_ENDIAN ? upward : downward)
4782 && GET_MODE_SIZE (promoted_mode) < UNITS_PER_WORD)
4784 || GET_CODE (entry_parm) == PARALLEL)
4786 /* If a BLKmode arrives in registers, copy it to a stack slot.
4787 Handle calls that pass values in multiple non-contiguous
4788 locations. The Irix 6 ABI has examples of this. */
4789 if (REG_P (entry_parm)
4790 || (GET_CODE (entry_parm) == PARALLEL
4791 && (!loaded_in_reg || !optimize)))
4793 int size = int_size_in_bytes (TREE_TYPE (parm));
4794 int size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
4797 /* Note that we will be storing an integral number of words.
4798 So we have to be careful to ensure that we allocate an
4799 integral number of words. We do this below in the
4800 assign_stack_local if space was not allocated in the argument
4801 list. If it was, this will not work if PARM_BOUNDARY is not
4802 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4803 if it becomes a problem. Exception is when BLKmode arrives
4804 with arguments not conforming to word_mode. */
4806 if (stack_parm == 0)
4808 stack_parm = assign_stack_local (BLKmode, size_stored, 0);
4809 PUT_MODE (stack_parm, GET_MODE (entry_parm));
4810 set_mem_attributes (stack_parm, parm, 1);
4812 else if (GET_CODE (entry_parm) == PARALLEL)
4814 else if (size != 0 && PARM_BOUNDARY % BITS_PER_WORD != 0)
4817 mem = validize_mem (stack_parm);
4819 /* Handle calls that pass values in multiple non-contiguous
4820 locations. The Irix 6 ABI has examples of this. */
4821 if (GET_CODE (entry_parm) == PARALLEL)
4822 emit_group_store (mem, entry_parm, TREE_TYPE (parm), size);
4827 /* If SIZE is that of a mode no bigger than a word, just use
4828 that mode's store operation. */
4829 else if (size <= UNITS_PER_WORD)
4831 enum machine_mode mode
4832 = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
4835 #ifdef BLOCK_REG_PADDING
4836 && (size == UNITS_PER_WORD
4837 || (BLOCK_REG_PADDING (mode, TREE_TYPE (parm), 1)
4838 != (BYTES_BIG_ENDIAN ? upward : downward)))
4842 rtx reg = gen_rtx_REG (mode, REGNO (entry_parm));
4843 emit_move_insn (change_address (mem, mode, 0), reg);
4846 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
4847 machine must be aligned to the left before storing
4848 to memory. Note that the previous test doesn't
4849 handle all cases (e.g. SIZE == 3). */
4850 else if (size != UNITS_PER_WORD
4851 #ifdef BLOCK_REG_PADDING
4852 && (BLOCK_REG_PADDING (mode, TREE_TYPE (parm), 1)
4860 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
4861 rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
4863 x = expand_binop (word_mode, ashl_optab, reg,
4864 GEN_INT (by), 0, 1, OPTAB_WIDEN);
4865 tem = change_address (mem, word_mode, 0);
4866 emit_move_insn (tem, x);
4869 move_block_from_reg (REGNO (entry_parm), mem,
4870 size_stored / UNITS_PER_WORD);
4873 move_block_from_reg (REGNO (entry_parm), mem,
4874 size_stored / UNITS_PER_WORD);
4876 /* If parm is already bound to register pair, don't change
4878 if (! DECL_RTL_SET_P (parm))
4879 SET_DECL_RTL (parm, stack_parm);
4881 else if (! ((! optimize
4882 && ! DECL_REGISTER (parm))
4883 || TREE_SIDE_EFFECTS (parm)
4884 /* If -ffloat-store specified, don't put explicit
4885 float variables into registers. */
4886 || (flag_float_store
4887 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4888 /* Always assign pseudo to structure return or item passed
4889 by invisible reference. */
4890 || passed_pointer || parm == function_result_decl)
4892 /* Store the parm in a pseudoregister during the function, but we
4893 may need to do it in a wider mode. */
4896 unsigned int regno, regnoi = 0, regnor = 0;
4898 unsignedp = TYPE_UNSIGNED (TREE_TYPE (parm));
4900 promoted_nominal_mode
4901 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4903 parmreg = gen_reg_rtx (promoted_nominal_mode);
4904 mark_user_reg (parmreg);
4906 /* If this was an item that we received a pointer to, set DECL_RTL
4910 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)),
4912 set_mem_attributes (x, parm, 1);
4913 SET_DECL_RTL (parm, x);
4917 SET_DECL_RTL (parm, parmreg);
4918 maybe_set_unchanging (DECL_RTL (parm), parm);
4921 /* Copy the value into the register. */
4922 if (nominal_mode != passed_mode
4923 || promoted_nominal_mode != promoted_mode)
4926 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4927 mode, by the caller. We now have to convert it to
4928 NOMINAL_MODE, if different. However, PARMREG may be in
4929 a different mode than NOMINAL_MODE if it is being stored
4932 If ENTRY_PARM is a hard register, it might be in a register
4933 not valid for operating in its mode (e.g., an odd-numbered
4934 register for a DFmode). In that case, moves are the only
4935 thing valid, so we can't do a convert from there. This
4936 occurs when the calling sequence allow such misaligned
4939 In addition, the conversion may involve a call, which could
4940 clobber parameters which haven't been copied to pseudo
4941 registers yet. Therefore, we must first copy the parm to
4942 a pseudo reg here, and save the conversion until after all
4943 parameters have been moved. */
4945 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4947 emit_move_insn (tempreg, validize_mem (entry_parm));
4949 push_to_sequence (conversion_insns);
4950 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4952 if (GET_CODE (tempreg) == SUBREG
4953 && GET_MODE (tempreg) == nominal_mode
4954 && REG_P (SUBREG_REG (tempreg))
4955 && nominal_mode == passed_mode
4956 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm)
4957 && GET_MODE_SIZE (GET_MODE (tempreg))
4958 < GET_MODE_SIZE (GET_MODE (entry_parm)))
4960 /* The argument is already sign/zero extended, so note it
4962 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
4963 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
4966 /* TREE_USED gets set erroneously during expand_assignment. */
4967 save_tree_used = TREE_USED (parm);
4968 expand_assignment (parm,
4969 make_tree (nominal_type, tempreg), 0);
4970 TREE_USED (parm) = save_tree_used;
4971 conversion_insns = get_insns ();
4976 emit_move_insn (parmreg, validize_mem (entry_parm));
4978 /* If we were passed a pointer but the actual value
4979 can safely live in a register, put it in one. */
4980 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4981 /* If by-reference argument was promoted, demote it. */
4982 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
4984 && ! DECL_REGISTER (parm))
4985 || TREE_SIDE_EFFECTS (parm)
4986 /* If -ffloat-store specified, don't put explicit
4987 float variables into registers. */
4988 || (flag_float_store
4989 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))))
4991 /* We can't use nominal_mode, because it will have been set to
4992 Pmode above. We must use the actual mode of the parm. */
4993 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4994 mark_user_reg (parmreg);
4995 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
4997 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
4998 int unsigned_p = TYPE_UNSIGNED (TREE_TYPE (parm));
4999 push_to_sequence (conversion_insns);
5000 emit_move_insn (tempreg, DECL_RTL (parm));
5002 convert_to_mode (GET_MODE (parmreg),
5005 emit_move_insn (parmreg, DECL_RTL (parm));
5006 conversion_insns = get_insns();
5011 emit_move_insn (parmreg, DECL_RTL (parm));
5012 SET_DECL_RTL (parm, parmreg);
5013 /* STACK_PARM is the pointer, not the parm, and PARMREG is
5017 #ifdef FUNCTION_ARG_CALLEE_COPIES
5018 /* If we are passed an arg by reference and it is our responsibility
5019 to make a copy, do it now.
5020 PASSED_TYPE and PASSED mode now refer to the pointer, not the
5021 original argument, so we must recreate them in the call to
5022 FUNCTION_ARG_CALLEE_COPIES. */
5023 /* ??? Later add code to handle the case that if the argument isn't
5024 modified, don't do the copy. */
5026 else if (passed_pointer
5027 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
5028 TYPE_MODE (TREE_TYPE (passed_type)),
5029 TREE_TYPE (passed_type),
5031 && ! TREE_ADDRESSABLE (TREE_TYPE (passed_type)))
5034 tree type = TREE_TYPE (passed_type);
5036 /* This sequence may involve a library call perhaps clobbering
5037 registers that haven't been copied to pseudos yet. */
5039 push_to_sequence (conversion_insns);
5041 if (!COMPLETE_TYPE_P (type)
5042 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
5043 /* This is a variable sized object. */
5044 copy = gen_rtx_MEM (BLKmode,
5045 allocate_dynamic_stack_space
5046 (expr_size (parm), NULL_RTX,
5047 TYPE_ALIGN (type)));
5049 copy = assign_stack_temp (TYPE_MODE (type),
5050 int_size_in_bytes (type), 1);
5051 set_mem_attributes (copy, parm, 1);
5053 store_expr (parm, copy, 0);
5054 emit_move_insn (parmreg, XEXP (copy, 0));
5055 conversion_insns = get_insns ();
5059 #endif /* FUNCTION_ARG_CALLEE_COPIES */
5061 /* In any case, record the parm's desired stack location
5062 in case we later discover it must live in the stack.
5064 If it is a COMPLEX value, store the stack location for both
5067 if (GET_CODE (parmreg) == CONCAT)
5068 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
5070 regno = REGNO (parmreg);
5072 if (regno >= max_parm_reg)
5075 int old_max_parm_reg = max_parm_reg;
5077 /* It's slow to expand this one register at a time,
5078 but it's also rare and we need max_parm_reg to be
5079 precisely correct. */
5080 max_parm_reg = regno + 1;
5081 new = ggc_realloc (parm_reg_stack_loc,
5082 max_parm_reg * sizeof (rtx));
5083 memset (new + old_max_parm_reg, 0,
5084 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
5085 parm_reg_stack_loc = new;
5088 if (GET_CODE (parmreg) == CONCAT)
5090 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
5092 regnor = REGNO (gen_realpart (submode, parmreg));
5093 regnoi = REGNO (gen_imagpart (submode, parmreg));
5095 if (stack_parm != 0)
5097 parm_reg_stack_loc[regnor]
5098 = gen_realpart (submode, stack_parm);
5099 parm_reg_stack_loc[regnoi]
5100 = gen_imagpart (submode, stack_parm);
5104 parm_reg_stack_loc[regnor] = 0;
5105 parm_reg_stack_loc[regnoi] = 0;
5109 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
5111 /* Mark the register as eliminable if we did no conversion
5112 and it was copied from memory at a fixed offset,
5113 and the arg pointer was not copied to a pseudo-reg.
5114 If the arg pointer is a pseudo reg or the offset formed
5115 an invalid address, such memory-equivalences
5116 as we make here would screw up life analysis for it. */
5117 if (nominal_mode == passed_mode
5120 && GET_CODE (stack_parm) == MEM
5121 && locate.offset.var == 0
5122 && reg_mentioned_p (virtual_incoming_args_rtx,
5123 XEXP (stack_parm, 0)))
5125 rtx linsn = get_last_insn ();
5128 /* Mark complex types separately. */
5129 if (GET_CODE (parmreg) == CONCAT)
5130 /* Scan backwards for the set of the real and
5132 for (sinsn = linsn; sinsn != 0;
5133 sinsn = prev_nonnote_insn (sinsn))
5135 set = single_set (sinsn);
5137 && SET_DEST (set) == regno_reg_rtx [regnoi])
5139 = gen_rtx_EXPR_LIST (REG_EQUIV,
5140 parm_reg_stack_loc[regnoi],
5143 && SET_DEST (set) == regno_reg_rtx [regnor])
5145 = gen_rtx_EXPR_LIST (REG_EQUIV,
5146 parm_reg_stack_loc[regnor],
5149 else if ((set = single_set (linsn)) != 0
5150 && SET_DEST (set) == parmreg)
5152 = gen_rtx_EXPR_LIST (REG_EQUIV,
5153 stack_parm, REG_NOTES (linsn));
5156 /* For pointer data type, suggest pointer register. */
5157 if (POINTER_TYPE_P (TREE_TYPE (parm)))
5158 mark_reg_pointer (parmreg,
5159 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
5161 /* If something wants our address, try to use ADDRESSOF. */
5162 if (TREE_ADDRESSABLE (parm))
5164 /* If we end up putting something into the stack,
5165 fixup_var_refs_insns will need to make a pass over
5166 all the instructions. It looks through the pending
5167 sequences -- but it can't see the ones in the
5168 CONVERSION_INSNS, if they're not on the sequence
5169 stack. So, we go back to that sequence, just so that
5170 the fixups will happen. */
5171 push_to_sequence (conversion_insns);
5172 put_var_into_stack (parm, /*rescan=*/true);
5173 conversion_insns = get_insns ();
5179 /* Value must be stored in the stack slot STACK_PARM
5180 during function execution. */
5182 if (promoted_mode != nominal_mode)
5184 /* Conversion is required. */
5185 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
5187 emit_move_insn (tempreg, validize_mem (entry_parm));
5189 push_to_sequence (conversion_insns);
5190 entry_parm = convert_to_mode (nominal_mode, tempreg,
5191 TYPE_UNSIGNED (TREE_TYPE (parm)));
5193 /* ??? This may need a big-endian conversion on sparc64. */
5194 stack_parm = adjust_address (stack_parm, nominal_mode, 0);
5196 conversion_insns = get_insns ();
5201 if (entry_parm != stack_parm)
5203 if (stack_parm == 0)
5206 = assign_stack_local (GET_MODE (entry_parm),
5207 GET_MODE_SIZE (GET_MODE (entry_parm)),
5209 set_mem_attributes (stack_parm, parm, 1);
5212 if (promoted_mode != nominal_mode)
5214 push_to_sequence (conversion_insns);
5215 emit_move_insn (validize_mem (stack_parm),
5216 validize_mem (entry_parm));
5217 conversion_insns = get_insns ();
5221 emit_move_insn (validize_mem (stack_parm),
5222 validize_mem (entry_parm));
5225 SET_DECL_RTL (parm, stack_parm);
5229 if (targetm.calls.split_complex_arg && fnargs != orig_fnargs)
5231 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm))
5233 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE
5234 && targetm.calls.split_complex_arg (TREE_TYPE (parm)))
5236 rtx tmp, real, imag;
5237 enum machine_mode inner = GET_MODE_INNER (DECL_MODE (parm));
5239 real = DECL_RTL (fnargs);
5240 imag = DECL_RTL (TREE_CHAIN (fnargs));
5241 if (inner != GET_MODE (real))
5243 real = gen_lowpart_SUBREG (inner, real);
5244 imag = gen_lowpart_SUBREG (inner, imag);
5246 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
5247 SET_DECL_RTL (parm, tmp);
5249 real = DECL_INCOMING_RTL (fnargs);
5250 imag = DECL_INCOMING_RTL (TREE_CHAIN (fnargs));
5251 if (inner != GET_MODE (real))
5253 real = gen_lowpart_SUBREG (inner, real);
5254 imag = gen_lowpart_SUBREG (inner, imag);
5256 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
5257 set_decl_incoming_rtl (parm, tmp);
5258 fnargs = TREE_CHAIN (fnargs);
5262 SET_DECL_RTL (parm, DECL_RTL (fnargs));
5263 set_decl_incoming_rtl (parm, DECL_INCOMING_RTL (fnargs));
5265 /* Set MEM_EXPR to the original decl, i.e. to PARM,
5266 instead of the copy of decl, i.e. FNARGS. */
5267 if (DECL_INCOMING_RTL (parm)
5268 && GET_CODE (DECL_INCOMING_RTL (parm)) == MEM)
5269 set_mem_expr (DECL_INCOMING_RTL (parm), parm);
5271 fnargs = TREE_CHAIN (fnargs);
5275 /* Output all parameter conversion instructions (possibly including calls)
5276 now that all parameters have been copied out of hard registers. */
5277 emit_insn (conversion_insns);
5279 /* If we are receiving a struct value address as the first argument, set up
5280 the RTL for the function result. As this might require code to convert
5281 the transmitted address to Pmode, we do this here to ensure that possible
5282 preliminary conversions of the address have been emitted already. */
5283 if (function_result_decl)
5285 tree result = DECL_RESULT (fndecl);
5286 rtx addr = DECL_RTL (function_result_decl);
5289 addr = convert_memory_address (Pmode, addr);
5290 x = gen_rtx_MEM (DECL_MODE (result), addr);
5291 set_mem_attributes (x, result, 1);
5292 SET_DECL_RTL (result, x);
5295 last_parm_insn = get_last_insn ();
5297 /* We have aligned all the args, so add space for the pretend args. */
5298 stack_args_size.constant += extra_pretend_bytes;
5299 current_function_args_size = stack_args_size.constant;
5301 /* Adjust function incoming argument size for alignment and
5304 #ifdef REG_PARM_STACK_SPACE
5305 current_function_args_size = MAX (current_function_args_size,
5306 REG_PARM_STACK_SPACE (fndecl));
5309 current_function_args_size
5310 = ((current_function_args_size + STACK_BYTES - 1)
5311 / STACK_BYTES) * STACK_BYTES;
5313 #ifdef ARGS_GROW_DOWNWARD
5314 current_function_arg_offset_rtx
5315 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
5316 : expand_expr (size_diffop (stack_args_size.var,
5317 size_int (-stack_args_size.constant)),
5318 NULL_RTX, VOIDmode, 0));
5320 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
5323 /* See how many bytes, if any, of its args a function should try to pop
5326 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
5327 current_function_args_size);
5329 /* For stdarg.h function, save info about
5330 regs and stack space used by the named args. */
5332 current_function_args_info = args_so_far;
5334 /* Set the rtx used for the function return value. Put this in its
5335 own variable so any optimizers that need this information don't have
5336 to include tree.h. Do this here so it gets done when an inlined
5337 function gets output. */
5339 current_function_return_rtx
5340 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
5341 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
5343 /* If scalar return value was computed in a pseudo-reg, or was a named
5344 return value that got dumped to the stack, copy that to the hard
5346 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
5348 tree decl_result = DECL_RESULT (fndecl);
5349 rtx decl_rtl = DECL_RTL (decl_result);
5351 if (REG_P (decl_rtl)
5352 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5353 : DECL_REGISTER (decl_result))
5357 #ifdef FUNCTION_OUTGOING_VALUE
5358 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
5361 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
5364 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
5365 /* The delay slot scheduler assumes that current_function_return_rtx
5366 holds the hard register containing the return value, not a
5367 temporary pseudo. */
5368 current_function_return_rtx = real_decl_rtl;
5373 /* If ARGS contains entries with complex types, split the entry into two
5374 entries of the component type. Return a new list of substitutions are
5375 needed, else the old list. */
5378 split_complex_args (tree args)
5382 /* Before allocating memory, check for the common case of no complex. */
5383 for (p = args; p; p = TREE_CHAIN (p))
5385 tree type = TREE_TYPE (p);
5386 if (TREE_CODE (type) == COMPLEX_TYPE
5387 && targetm.calls.split_complex_arg (type))
5393 args = copy_list (args);
5395 for (p = args; p; p = TREE_CHAIN (p))
5397 tree type = TREE_TYPE (p);
5398 if (TREE_CODE (type) == COMPLEX_TYPE
5399 && targetm.calls.split_complex_arg (type))
5402 tree subtype = TREE_TYPE (type);
5404 /* Rewrite the PARM_DECL's type with its component. */
5405 TREE_TYPE (p) = subtype;
5406 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
5407 DECL_MODE (p) = VOIDmode;
5408 DECL_SIZE (p) = NULL;
5409 DECL_SIZE_UNIT (p) = NULL;
5412 /* Build a second synthetic decl. */
5413 decl = build_decl (PARM_DECL, NULL_TREE, subtype);
5414 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
5415 layout_decl (decl, 0);
5417 /* Splice it in; skip the new decl. */
5418 TREE_CHAIN (decl) = TREE_CHAIN (p);
5419 TREE_CHAIN (p) = decl;
5427 /* Indicate whether REGNO is an incoming argument to the current function
5428 that was promoted to a wider mode. If so, return the RTX for the
5429 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5430 that REGNO is promoted from and whether the promotion was signed or
5434 promoted_input_arg (unsigned int regno, enum machine_mode *pmode, int *punsignedp)
5438 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
5439 arg = TREE_CHAIN (arg))
5440 if (REG_P (DECL_INCOMING_RTL (arg))
5441 && REGNO (DECL_INCOMING_RTL (arg)) == regno
5442 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
5444 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
5445 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (arg));
5447 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
5448 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
5449 && mode != DECL_MODE (arg))
5451 *pmode = DECL_MODE (arg);
5452 *punsignedp = unsignedp;
5453 return DECL_INCOMING_RTL (arg);
5461 /* Compute the size and offset from the start of the stacked arguments for a
5462 parm passed in mode PASSED_MODE and with type TYPE.
5464 INITIAL_OFFSET_PTR points to the current offset into the stacked
5467 The starting offset and size for this parm are returned in
5468 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
5469 nonzero, the offset is that of stack slot, which is returned in
5470 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
5471 padding required from the initial offset ptr to the stack slot.
5473 IN_REGS is nonzero if the argument will be passed in registers. It will
5474 never be set if REG_PARM_STACK_SPACE is not defined.
5476 FNDECL is the function in which the argument was defined.
5478 There are two types of rounding that are done. The first, controlled by
5479 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5480 list to be aligned to the specific boundary (in bits). This rounding
5481 affects the initial and starting offsets, but not the argument size.
5483 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5484 optionally rounds the size of the parm to PARM_BOUNDARY. The
5485 initial offset is not affected by this rounding, while the size always
5486 is and the starting offset may be. */
5488 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
5489 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
5490 callers pass in the total size of args so far as
5491 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
5494 locate_and_pad_parm (enum machine_mode passed_mode, tree type, int in_regs,
5495 int partial, tree fndecl ATTRIBUTE_UNUSED,
5496 struct args_size *initial_offset_ptr,
5497 struct locate_and_pad_arg_data *locate)
5500 enum direction where_pad;
5502 int reg_parm_stack_space = 0;
5503 int part_size_in_regs;
5505 #ifdef REG_PARM_STACK_SPACE
5506 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5508 /* If we have found a stack parm before we reach the end of the
5509 area reserved for registers, skip that area. */
5512 if (reg_parm_stack_space > 0)
5514 if (initial_offset_ptr->var)
5516 initial_offset_ptr->var
5517 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5518 ssize_int (reg_parm_stack_space));
5519 initial_offset_ptr->constant = 0;
5521 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5522 initial_offset_ptr->constant = reg_parm_stack_space;
5525 #endif /* REG_PARM_STACK_SPACE */
5527 part_size_in_regs = 0;
5528 if (reg_parm_stack_space == 0)
5529 part_size_in_regs = ((partial * UNITS_PER_WORD)
5530 / (PARM_BOUNDARY / BITS_PER_UNIT)
5531 * (PARM_BOUNDARY / BITS_PER_UNIT));
5534 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5535 where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5536 boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5537 locate->where_pad = where_pad;
5539 #ifdef ARGS_GROW_DOWNWARD
5540 locate->slot_offset.constant = -initial_offset_ptr->constant;
5541 if (initial_offset_ptr->var)
5542 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
5543 initial_offset_ptr->var);
5547 if (where_pad != none
5548 && (!host_integerp (sizetree, 1)
5549 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5550 s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
5551 SUB_PARM_SIZE (locate->slot_offset, s2);
5554 locate->slot_offset.constant += part_size_in_regs;
5557 #ifdef REG_PARM_STACK_SPACE
5558 || REG_PARM_STACK_SPACE (fndecl) > 0
5561 pad_to_arg_alignment (&locate->slot_offset, boundary,
5562 &locate->alignment_pad);
5564 locate->size.constant = (-initial_offset_ptr->constant
5565 - locate->slot_offset.constant);
5566 if (initial_offset_ptr->var)
5567 locate->size.var = size_binop (MINUS_EXPR,
5568 size_binop (MINUS_EXPR,
5570 initial_offset_ptr->var),
5571 locate->slot_offset.var);
5573 /* Pad_below needs the pre-rounded size to know how much to pad
5575 locate->offset = locate->slot_offset;
5576 if (where_pad == downward)
5577 pad_below (&locate->offset, passed_mode, sizetree);
5579 #else /* !ARGS_GROW_DOWNWARD */
5581 #ifdef REG_PARM_STACK_SPACE
5582 || REG_PARM_STACK_SPACE (fndecl) > 0
5585 pad_to_arg_alignment (initial_offset_ptr, boundary,
5586 &locate->alignment_pad);
5587 locate->slot_offset = *initial_offset_ptr;
5589 #ifdef PUSH_ROUNDING
5590 if (passed_mode != BLKmode)
5591 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5594 /* Pad_below needs the pre-rounded size to know how much to pad below
5595 so this must be done before rounding up. */
5596 locate->offset = locate->slot_offset;
5597 if (where_pad == downward)
5598 pad_below (&locate->offset, passed_mode, sizetree);
5600 if (where_pad != none
5601 && (!host_integerp (sizetree, 1)
5602 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5603 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5605 ADD_PARM_SIZE (locate->size, sizetree);
5607 locate->size.constant -= part_size_in_regs;
5608 #endif /* ARGS_GROW_DOWNWARD */
5611 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5612 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5615 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
5616 struct args_size *alignment_pad)
5618 tree save_var = NULL_TREE;
5619 HOST_WIDE_INT save_constant = 0;
5620 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5621 HOST_WIDE_INT sp_offset = STACK_POINTER_OFFSET;
5623 #ifdef SPARC_STACK_BOUNDARY_HACK
5624 /* The sparc port has a bug. It sometimes claims a STACK_BOUNDARY
5625 higher than the real alignment of %sp. However, when it does this,
5626 the alignment of %sp+STACK_POINTER_OFFSET will be STACK_BOUNDARY.
5627 This is a temporary hack while the sparc port is fixed. */
5628 if (SPARC_STACK_BOUNDARY_HACK)
5632 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5634 save_var = offset_ptr->var;
5635 save_constant = offset_ptr->constant;
5638 alignment_pad->var = NULL_TREE;
5639 alignment_pad->constant = 0;
5641 if (boundary > BITS_PER_UNIT)
5643 if (offset_ptr->var)
5645 tree sp_offset_tree = ssize_int (sp_offset);
5646 tree offset = size_binop (PLUS_EXPR,
5647 ARGS_SIZE_TREE (*offset_ptr),
5649 #ifdef ARGS_GROW_DOWNWARD
5650 tree rounded = round_down (offset, boundary / BITS_PER_UNIT);
5652 tree rounded = round_up (offset, boundary / BITS_PER_UNIT);
5655 offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
5656 /* ARGS_SIZE_TREE includes constant term. */
5657 offset_ptr->constant = 0;
5658 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5659 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5664 offset_ptr->constant = -sp_offset +
5665 #ifdef ARGS_GROW_DOWNWARD
5666 FLOOR_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
5668 CEIL_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
5670 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5671 alignment_pad->constant = offset_ptr->constant - save_constant;
5677 pad_below (struct args_size *offset_ptr, enum machine_mode passed_mode, tree sizetree)
5679 if (passed_mode != BLKmode)
5681 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5682 offset_ptr->constant
5683 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5684 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5685 - GET_MODE_SIZE (passed_mode));
5689 if (TREE_CODE (sizetree) != INTEGER_CST
5690 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5692 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5693 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5695 ADD_PARM_SIZE (*offset_ptr, s2);
5696 SUB_PARM_SIZE (*offset_ptr, sizetree);
5701 /* Walk the tree of blocks describing the binding levels within a function
5702 and warn about variables the might be killed by setjmp or vfork.
5703 This is done after calling flow_analysis and before global_alloc
5704 clobbers the pseudo-regs to hard regs. */
5707 setjmp_vars_warning (tree block)
5711 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5713 if (TREE_CODE (decl) == VAR_DECL
5714 && DECL_RTL_SET_P (decl)
5715 && REG_P (DECL_RTL (decl))
5716 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5717 warning ("%Jvariable '%D' might be clobbered by `longjmp' or `vfork'",
5721 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5722 setjmp_vars_warning (sub);
5725 /* Do the appropriate part of setjmp_vars_warning
5726 but for arguments instead of local variables. */
5729 setjmp_args_warning (void)
5732 for (decl = DECL_ARGUMENTS (current_function_decl);
5733 decl; decl = TREE_CHAIN (decl))
5734 if (DECL_RTL (decl) != 0
5735 && REG_P (DECL_RTL (decl))
5736 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5737 warning ("%Jargument '%D' might be clobbered by `longjmp' or `vfork'",
5741 /* If this function call setjmp, put all vars into the stack
5742 unless they were declared `register'. */
5745 setjmp_protect (tree block)
5748 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5749 if ((TREE_CODE (decl) == VAR_DECL
5750 || TREE_CODE (decl) == PARM_DECL)
5751 && DECL_RTL (decl) != 0
5752 && (REG_P (DECL_RTL (decl))
5753 || (GET_CODE (DECL_RTL (decl)) == MEM
5754 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5755 /* If this variable came from an inline function, it must be
5756 that its life doesn't overlap the setjmp. If there was a
5757 setjmp in the function, it would already be in memory. We
5758 must exclude such variable because their DECL_RTL might be
5759 set to strange things such as virtual_stack_vars_rtx. */
5760 && ! DECL_FROM_INLINE (decl)
5762 #ifdef NON_SAVING_SETJMP
5763 /* If longjmp doesn't restore the registers,
5764 don't put anything in them. */
5768 ! DECL_REGISTER (decl)))
5769 put_var_into_stack (decl, /*rescan=*/true);
5770 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5771 setjmp_protect (sub);
5774 /* Like the previous function, but for args instead of local variables. */
5777 setjmp_protect_args (void)
5780 for (decl = DECL_ARGUMENTS (current_function_decl);
5781 decl; decl = TREE_CHAIN (decl))
5782 if ((TREE_CODE (decl) == VAR_DECL
5783 || TREE_CODE (decl) == PARM_DECL)
5784 && DECL_RTL (decl) != 0
5785 && (REG_P (DECL_RTL (decl))
5786 || (GET_CODE (DECL_RTL (decl)) == MEM
5787 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5789 /* If longjmp doesn't restore the registers,
5790 don't put anything in them. */
5791 #ifdef NON_SAVING_SETJMP
5795 ! DECL_REGISTER (decl)))
5796 put_var_into_stack (decl, /*rescan=*/true);
5799 /* Convert a stack slot address ADDR for variable VAR
5800 (from a containing function)
5801 into an address valid in this function (using a static chain). */
5804 fix_lexical_addr (rtx addr, tree var)
5807 HOST_WIDE_INT displacement;
5808 tree context = decl_function_context (var);
5809 struct function *fp;
5812 /* If this is the present function, we need not do anything. */
5813 if (context == current_function_decl)
5816 fp = find_function_data (context);
5818 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5819 addr = XEXP (XEXP (addr, 0), 0);
5821 /* Decode given address as base reg plus displacement. */
5823 basereg = addr, displacement = 0;
5824 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5825 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5832 /* Use same offset, relative to appropriate static chain or argument
5834 return plus_constant (base, displacement);
5837 /* Put all this function's BLOCK nodes including those that are chained
5838 onto the first block into a vector, and return it.
5839 Also store in each NOTE for the beginning or end of a block
5840 the index of that block in the vector.
5841 The arguments are BLOCK, the chain of top-level blocks of the function,
5842 and INSNS, the insn chain of the function. */
5845 identify_blocks (void)
5848 tree *block_vector, *last_block_vector;
5850 tree block = DECL_INITIAL (current_function_decl);
5855 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5856 depth-first order. */
5857 block_vector = get_block_vector (block, &n_blocks);
5858 block_stack = xmalloc (n_blocks * sizeof (tree));
5860 last_block_vector = identify_blocks_1 (get_insns (),
5862 block_vector + n_blocks,
5865 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5866 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5867 if (0 && last_block_vector != block_vector + n_blocks)
5870 free (block_vector);
5874 /* Subroutine of identify_blocks. Do the block substitution on the
5875 insn chain beginning with INSNS.
5877 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5878 BLOCK_VECTOR is incremented for each block seen. */
5881 identify_blocks_1 (rtx insns, tree *block_vector, tree *end_block_vector,
5882 tree *orig_block_stack)
5885 tree *block_stack = orig_block_stack;
5887 for (insn = insns; insn; insn = NEXT_INSN (insn))
5889 if (GET_CODE (insn) == NOTE)
5891 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5895 /* If there are more block notes than BLOCKs, something
5897 if (block_vector == end_block_vector)
5900 b = *block_vector++;
5901 NOTE_BLOCK (insn) = b;
5904 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5906 /* If there are more NOTE_INSN_BLOCK_ENDs than
5907 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
5908 if (block_stack == orig_block_stack)
5911 NOTE_BLOCK (insn) = *--block_stack;
5916 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
5917 something is badly wrong. */
5918 if (block_stack != orig_block_stack)
5921 return block_vector;
5924 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
5925 and create duplicate blocks. */
5926 /* ??? Need an option to either create block fragments or to create
5927 abstract origin duplicates of a source block. It really depends
5928 on what optimization has been performed. */
5931 reorder_blocks (void)
5933 tree block = DECL_INITIAL (current_function_decl);
5934 varray_type block_stack;
5936 if (block == NULL_TREE)
5939 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
5941 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
5942 clear_block_marks (block);
5944 /* Prune the old trees away, so that they don't get in the way. */
5945 BLOCK_SUBBLOCKS (block) = NULL_TREE;
5946 BLOCK_CHAIN (block) = NULL_TREE;
5948 /* Recreate the block tree from the note nesting. */
5949 reorder_blocks_1 (get_insns (), block, &block_stack);
5950 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
5952 /* Remove deleted blocks from the block fragment chains. */
5953 reorder_fix_fragments (block);
5956 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
5959 clear_block_marks (tree block)
5963 TREE_ASM_WRITTEN (block) = 0;
5964 clear_block_marks (BLOCK_SUBBLOCKS (block));
5965 block = BLOCK_CHAIN (block);
5970 reorder_blocks_1 (rtx insns, tree current_block, varray_type *p_block_stack)
5974 for (insn = insns; insn; insn = NEXT_INSN (insn))
5976 if (GET_CODE (insn) == NOTE)
5978 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5980 tree block = NOTE_BLOCK (insn);
5982 /* If we have seen this block before, that means it now
5983 spans multiple address regions. Create a new fragment. */
5984 if (TREE_ASM_WRITTEN (block))
5986 tree new_block = copy_node (block);
5989 origin = (BLOCK_FRAGMENT_ORIGIN (block)
5990 ? BLOCK_FRAGMENT_ORIGIN (block)
5992 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
5993 BLOCK_FRAGMENT_CHAIN (new_block)
5994 = BLOCK_FRAGMENT_CHAIN (origin);
5995 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
5997 NOTE_BLOCK (insn) = new_block;
6001 BLOCK_SUBBLOCKS (block) = 0;
6002 TREE_ASM_WRITTEN (block) = 1;
6003 /* When there's only one block for the entire function,
6004 current_block == block and we mustn't do this, it
6005 will cause infinite recursion. */
6006 if (block != current_block)
6008 BLOCK_SUPERCONTEXT (block) = current_block;
6009 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
6010 BLOCK_SUBBLOCKS (current_block) = block;
6011 current_block = block;
6013 VARRAY_PUSH_TREE (*p_block_stack, block);
6015 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
6017 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
6018 VARRAY_POP (*p_block_stack);
6019 BLOCK_SUBBLOCKS (current_block)
6020 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
6021 current_block = BLOCK_SUPERCONTEXT (current_block);
6027 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
6028 appears in the block tree, select one of the fragments to become
6029 the new origin block. */
6032 reorder_fix_fragments (tree block)
6036 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
6037 tree new_origin = NULL_TREE;
6041 if (! TREE_ASM_WRITTEN (dup_origin))
6043 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
6045 /* Find the first of the remaining fragments. There must
6046 be at least one -- the current block. */
6047 while (! TREE_ASM_WRITTEN (new_origin))
6048 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
6049 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
6052 else if (! dup_origin)
6055 /* Re-root the rest of the fragments to the new origin. In the
6056 case that DUP_ORIGIN was null, that means BLOCK was the origin
6057 of a chain of fragments and we want to remove those fragments
6058 that didn't make it to the output. */
6061 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
6066 if (TREE_ASM_WRITTEN (chain))
6068 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
6070 pp = &BLOCK_FRAGMENT_CHAIN (chain);
6072 chain = BLOCK_FRAGMENT_CHAIN (chain);
6077 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
6078 block = BLOCK_CHAIN (block);
6082 /* Reverse the order of elements in the chain T of blocks,
6083 and return the new head of the chain (old last element). */
6086 blocks_nreverse (tree t)
6088 tree prev = 0, decl, next;
6089 for (decl = t; decl; decl = next)
6091 next = BLOCK_CHAIN (decl);
6092 BLOCK_CHAIN (decl) = prev;
6098 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
6099 non-NULL, list them all into VECTOR, in a depth-first preorder
6100 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
6104 all_blocks (tree block, tree *vector)
6110 TREE_ASM_WRITTEN (block) = 0;
6112 /* Record this block. */
6114 vector[n_blocks] = block;
6118 /* Record the subblocks, and their subblocks... */
6119 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
6120 vector ? vector + n_blocks : 0);
6121 block = BLOCK_CHAIN (block);
6127 /* Return a vector containing all the blocks rooted at BLOCK. The
6128 number of elements in the vector is stored in N_BLOCKS_P. The
6129 vector is dynamically allocated; it is the caller's responsibility
6130 to call `free' on the pointer returned. */
6133 get_block_vector (tree block, int *n_blocks_p)
6137 *n_blocks_p = all_blocks (block, NULL);
6138 block_vector = xmalloc (*n_blocks_p * sizeof (tree));
6139 all_blocks (block, block_vector);
6141 return block_vector;
6144 static GTY(()) int next_block_index = 2;
6146 /* Set BLOCK_NUMBER for all the blocks in FN. */
6149 number_blocks (tree fn)
6155 /* For SDB and XCOFF debugging output, we start numbering the blocks
6156 from 1 within each function, rather than keeping a running
6158 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6159 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
6160 next_block_index = 1;
6163 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
6165 /* The top-level BLOCK isn't numbered at all. */
6166 for (i = 1; i < n_blocks; ++i)
6167 /* We number the blocks from two. */
6168 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
6170 free (block_vector);
6175 /* If VAR is present in a subblock of BLOCK, return the subblock. */
6178 debug_find_var_in_block_tree (tree var, tree block)
6182 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
6186 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
6188 tree ret = debug_find_var_in_block_tree (var, t);
6196 /* Allocate a function structure for FNDECL and set its contents
6200 allocate_struct_function (tree fndecl)
6203 tree fntype = fndecl ? TREE_TYPE (fndecl) : NULL_TREE;
6205 cfun = ggc_alloc_cleared (sizeof (struct function));
6207 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
6209 cfun->stack_alignment_needed = STACK_BOUNDARY;
6210 cfun->preferred_stack_boundary = STACK_BOUNDARY;
6212 current_function_funcdef_no = funcdef_no++;
6214 cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL;
6216 init_stmt_for_function ();
6217 init_eh_for_function ();
6219 lang_hooks.function.init (cfun);
6220 if (init_machine_status)
6221 cfun->machine = (*init_machine_status) ();
6226 DECL_STRUCT_FUNCTION (fndecl) = cfun;
6227 cfun->decl = fndecl;
6229 result = DECL_RESULT (fndecl);
6230 if (aggregate_value_p (result, fndecl))
6232 #ifdef PCC_STATIC_STRUCT_RETURN
6233 current_function_returns_pcc_struct = 1;
6235 current_function_returns_struct = 1;
6238 current_function_returns_pointer = POINTER_TYPE_P (TREE_TYPE (result));
6240 current_function_stdarg
6242 && TYPE_ARG_TYPES (fntype) != 0
6243 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
6244 != void_type_node));
6247 /* Reset cfun, and other non-struct-function variables to defaults as
6248 appropriate for emitting rtl at the start of a function. */
6251 prepare_function_start (tree fndecl)
6253 if (fndecl && DECL_STRUCT_FUNCTION (fndecl))
6254 cfun = DECL_STRUCT_FUNCTION (fndecl);
6256 allocate_struct_function (fndecl);
6258 init_varasm_status (cfun);
6261 cse_not_expected = ! optimize;
6263 /* Caller save not needed yet. */
6264 caller_save_needed = 0;
6266 /* We haven't done register allocation yet. */
6269 /* Indicate that we need to distinguish between the return value of the
6270 present function and the return value of a function being called. */
6271 rtx_equal_function_value_matters = 1;
6273 /* Indicate that we have not instantiated virtual registers yet. */
6274 virtuals_instantiated = 0;
6276 /* Indicate that we want CONCATs now. */
6277 generating_concat_p = 1;
6279 /* Indicate we have no need of a frame pointer yet. */
6280 frame_pointer_needed = 0;
6283 /* Initialize the rtl expansion mechanism so that we can do simple things
6284 like generate sequences. This is used to provide a context during global
6285 initialization of some passes. */
6287 init_dummy_function_start (void)
6289 prepare_function_start (NULL);
6292 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6293 and initialize static variables for generating RTL for the statements
6297 init_function_start (tree subr)
6299 prepare_function_start (subr);
6301 /* Within function body, compute a type's size as soon it is laid out. */
6302 immediate_size_expand++;
6304 /* Prevent ever trying to delete the first instruction of a
6305 function. Also tell final how to output a linenum before the
6306 function prologue. Note linenums could be missing, e.g. when
6307 compiling a Java .class file. */
6308 if (! DECL_IS_BUILTIN (subr))
6309 emit_line_note (DECL_SOURCE_LOCATION (subr));
6311 /* Make sure first insn is a note even if we don't want linenums.
6312 This makes sure the first insn will never be deleted.
6313 Also, final expects a note to appear there. */
6314 emit_note (NOTE_INSN_DELETED);
6316 /* Warn if this value is an aggregate type,
6317 regardless of which calling convention we are using for it. */
6318 if (warn_aggregate_return
6319 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6320 warning ("function returns an aggregate");
6323 /* Make sure all values used by the optimization passes have sane
6326 init_function_for_compilation (void)
6330 /* No prologue/epilogue insns yet. */
6331 VARRAY_GROW (prologue, 0);
6332 VARRAY_GROW (epilogue, 0);
6333 VARRAY_GROW (sibcall_epilogue, 0);
6336 /* Expand a call to __main at the beginning of a possible main function. */
6338 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6339 #undef HAS_INIT_SECTION
6340 #define HAS_INIT_SECTION
6344 expand_main_function (void)
6346 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
6347 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
6349 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
6353 /* Forcibly align the stack. */
6354 #ifdef STACK_GROWS_DOWNWARD
6355 tmp = expand_simple_binop (Pmode, AND, stack_pointer_rtx, GEN_INT(-align),
6356 stack_pointer_rtx, 1, OPTAB_WIDEN);
6358 tmp = expand_simple_binop (Pmode, PLUS, stack_pointer_rtx,
6359 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
6360 tmp = expand_simple_binop (Pmode, AND, tmp, GEN_INT (-align),
6361 stack_pointer_rtx, 1, OPTAB_WIDEN);
6363 if (tmp != stack_pointer_rtx)
6364 emit_move_insn (stack_pointer_rtx, tmp);
6366 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
6367 tmp = force_reg (Pmode, const0_rtx);
6368 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
6372 for (tmp = get_last_insn (); tmp; tmp = PREV_INSN (tmp))
6373 if (NOTE_P (tmp) && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_FUNCTION_BEG)
6376 emit_insn_before (seq, tmp);
6382 #ifndef HAS_INIT_SECTION
6383 emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0);
6387 /* The PENDING_SIZES represent the sizes of variable-sized types.
6388 Create RTL for the various sizes now (using temporary variables),
6389 so that we can refer to the sizes from the RTL we are generating
6390 for the current function. The PENDING_SIZES are a TREE_LIST. The
6391 TREE_VALUE of each node is a SAVE_EXPR. */
6394 expand_pending_sizes (tree pending_sizes)
6398 /* Evaluate now the sizes of any types declared among the arguments. */
6399 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
6401 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode, 0);
6402 /* Flush the queue in case this parameter declaration has
6408 /* Start the RTL for a new function, and set variables used for
6410 SUBR is the FUNCTION_DECL node.
6411 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6412 the function's parameters, which must be run at any return statement. */
6415 expand_function_start (tree subr, int parms_have_cleanups)
6417 /* Make sure volatile mem refs aren't considered
6418 valid operands of arithmetic insns. */
6419 init_recog_no_volatile ();
6421 current_function_profile
6423 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6425 current_function_limit_stack
6426 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6428 /* If the parameters of this function need cleaning up, get a label
6429 for the beginning of the code which executes those cleanups. This must
6430 be done before doing anything with return_label. */
6431 if (parms_have_cleanups)
6432 cleanup_label = gen_label_rtx ();
6436 /* Make the label for return statements to jump to. Do not special
6437 case machines with special return instructions -- they will be
6438 handled later during jump, ifcvt, or epilogue creation. */
6439 return_label = gen_label_rtx ();
6441 /* Initialize rtx used to return the value. */
6442 /* Do this before assign_parms so that we copy the struct value address
6443 before any library calls that assign parms might generate. */
6445 /* Decide whether to return the value in memory or in a register. */
6446 if (aggregate_value_p (DECL_RESULT (subr), subr))
6448 /* Returning something that won't go in a register. */
6449 rtx value_address = 0;
6451 #ifdef PCC_STATIC_STRUCT_RETURN
6452 if (current_function_returns_pcc_struct)
6454 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6455 value_address = assemble_static_space (size);
6460 rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 1);
6461 /* Expect to be passed the address of a place to store the value.
6462 If it is passed as an argument, assign_parms will take care of
6466 value_address = gen_reg_rtx (Pmode);
6467 emit_move_insn (value_address, sv);
6472 rtx x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
6473 set_mem_attributes (x, DECL_RESULT (subr), 1);
6474 SET_DECL_RTL (DECL_RESULT (subr), x);
6477 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6478 /* If return mode is void, this decl rtl should not be used. */
6479 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
6482 /* Compute the return values into a pseudo reg, which we will copy
6483 into the true return register after the cleanups are done. */
6485 /* In order to figure out what mode to use for the pseudo, we
6486 figure out what the mode of the eventual return register will
6487 actually be, and use that. */
6489 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
6492 /* Structures that are returned in registers are not aggregate_value_p,
6493 so we may see a PARALLEL or a REG. */
6494 if (REG_P (hard_reg))
6495 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg)));
6496 else if (GET_CODE (hard_reg) == PARALLEL)
6497 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
6501 /* Set DECL_REGISTER flag so that expand_function_end will copy the
6502 result to the real return register(s). */
6503 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6506 /* Initialize rtx for parameters and local variables.
6507 In some cases this requires emitting insns. */
6508 assign_parms (subr);
6510 /* If function gets a static chain arg, store it. */
6511 if (cfun->static_chain_decl)
6513 tree parm = cfun->static_chain_decl;
6514 rtx local = gen_reg_rtx (Pmode);
6516 set_decl_incoming_rtl (parm, static_chain_incoming_rtx);
6517 SET_DECL_RTL (parm, local);
6518 maybe_set_unchanging (local, parm);
6519 mark_reg_pointer (local, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
6521 emit_move_insn (local, static_chain_incoming_rtx);
6524 /* If the function receives a non-local goto, then store the
6525 bits we need to restore the frame pointer. */
6526 if (cfun->nonlocal_goto_save_area)
6531 /* ??? We need to do this save early. Unfortunately here is
6532 before the frame variable gets declared. Help out... */
6533 expand_var (TREE_OPERAND (cfun->nonlocal_goto_save_area, 0));
6535 t_save = build (ARRAY_REF, ptr_type_node, cfun->nonlocal_goto_save_area,
6536 integer_zero_node, NULL_TREE, NULL_TREE);
6537 r_save = expand_expr (t_save, NULL_RTX, VOIDmode, EXPAND_WRITE);
6539 emit_move_insn (r_save, virtual_stack_vars_rtx);
6540 update_nonlocal_goto_save_area ();
6543 /* The following was moved from init_function_start.
6544 The move is supposed to make sdb output more accurate. */
6545 /* Indicate the beginning of the function body,
6546 as opposed to parm setup. */
6547 emit_note (NOTE_INSN_FUNCTION_BEG);
6549 if (GET_CODE (get_last_insn ()) != NOTE)
6550 emit_note (NOTE_INSN_DELETED);
6551 parm_birth_insn = get_last_insn ();
6553 if (current_function_profile)
6556 PROFILE_HOOK (current_function_funcdef_no);
6560 /* After the display initializations is where the tail-recursion label
6561 should go, if we end up needing one. Ensure we have a NOTE here
6562 since some things (like trampolines) get placed before this. */
6563 tail_recursion_reentry = emit_note (NOTE_INSN_DELETED);
6565 /* Evaluate now the sizes of any types declared among the arguments. */
6566 expand_pending_sizes (nreverse (get_pending_sizes ()));
6568 /* Make sure there is a line number after the function entry setup code. */
6569 force_next_line_note ();
6572 /* Undo the effects of init_dummy_function_start. */
6574 expand_dummy_function_end (void)
6576 /* End any sequences that failed to be closed due to syntax errors. */
6577 while (in_sequence_p ())
6580 /* Outside function body, can't compute type's actual size
6581 until next function's body starts. */
6583 free_after_parsing (cfun);
6584 free_after_compilation (cfun);
6588 /* Call DOIT for each hard register used as a return value from
6589 the current function. */
6592 diddle_return_value (void (*doit) (rtx, void *), void *arg)
6594 rtx outgoing = current_function_return_rtx;
6599 if (REG_P (outgoing))
6600 (*doit) (outgoing, arg);
6601 else if (GET_CODE (outgoing) == PARALLEL)
6605 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6607 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6609 if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER)
6616 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
6618 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6622 clobber_return_register (void)
6624 diddle_return_value (do_clobber_return_reg, NULL);
6626 /* In case we do use pseudo to return value, clobber it too. */
6627 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6629 tree decl_result = DECL_RESULT (current_function_decl);
6630 rtx decl_rtl = DECL_RTL (decl_result);
6631 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
6633 do_clobber_return_reg (decl_rtl, NULL);
6639 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
6641 emit_insn (gen_rtx_USE (VOIDmode, reg));
6645 use_return_register (void)
6647 diddle_return_value (do_use_return_reg, NULL);
6650 /* Possibly warn about unused parameters. */
6652 do_warn_unused_parameter (tree fn)
6656 for (decl = DECL_ARGUMENTS (fn);
6657 decl; decl = TREE_CHAIN (decl))
6658 if (!TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6659 && DECL_NAME (decl) && !DECL_ARTIFICIAL (decl))
6660 warning ("%Junused parameter '%D'", decl, decl);
6663 static GTY(()) rtx initial_trampoline;
6665 /* Generate RTL for the end of the current function. */
6668 expand_function_end (void)
6672 finish_expr_for_function ();
6674 /* If arg_pointer_save_area was referenced only from a nested
6675 function, we will not have initialized it yet. Do that now. */
6676 if (arg_pointer_save_area && ! cfun->arg_pointer_save_area_init)
6677 get_arg_pointer_save_area (cfun);
6679 #ifdef NON_SAVING_SETJMP
6680 /* Don't put any variables in registers if we call setjmp
6681 on a machine that fails to restore the registers. */
6682 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6684 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6685 setjmp_protect (DECL_INITIAL (current_function_decl));
6687 setjmp_protect_args ();
6691 /* If we are doing stack checking and this function makes calls,
6692 do a stack probe at the start of the function to ensure we have enough
6693 space for another stack frame. */
6694 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6698 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6699 if (GET_CODE (insn) == CALL_INSN)
6702 probe_stack_range (STACK_CHECK_PROTECT,
6703 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6706 emit_insn_before (seq, tail_recursion_reentry);
6711 /* Possibly warn about unused parameters.
6712 When frontend does unit-at-a-time, the warning is already
6713 issued at finalization time. */
6714 if (warn_unused_parameter
6715 && !lang_hooks.callgraph.expand_function)
6716 do_warn_unused_parameter (current_function_decl);
6718 /* End any sequences that failed to be closed due to syntax errors. */
6719 while (in_sequence_p ())
6722 /* Outside function body, can't compute type's actual size
6723 until next function's body starts. */
6724 immediate_size_expand--;
6726 clear_pending_stack_adjust ();
6727 do_pending_stack_adjust ();
6729 /* @@@ This is a kludge. We want to ensure that instructions that
6730 may trap are not moved into the epilogue by scheduling, because
6731 we don't always emit unwind information for the epilogue.
6732 However, not all machine descriptions define a blockage insn, so
6733 emit an ASM_INPUT to act as one. */
6734 if (flag_non_call_exceptions)
6735 emit_insn (gen_rtx_ASM_INPUT (VOIDmode, ""));
6737 /* Mark the end of the function body.
6738 If control reaches this insn, the function can drop through
6739 without returning a value. */
6740 emit_note (NOTE_INSN_FUNCTION_END);
6742 /* Must mark the last line number note in the function, so that the test
6743 coverage code can avoid counting the last line twice. This just tells
6744 the code to ignore the immediately following line note, since there
6745 already exists a copy of this note somewhere above. This line number
6746 note is still needed for debugging though, so we can't delete it. */
6747 if (flag_test_coverage)
6748 emit_note (NOTE_INSN_REPEATED_LINE_NUMBER);
6750 /* Output a linenumber for the end of the function.
6751 SDB depends on this. */
6752 force_next_line_note ();
6753 emit_line_note (input_location);
6755 /* Before the return label (if any), clobber the return
6756 registers so that they are not propagated live to the rest of
6757 the function. This can only happen with functions that drop
6758 through; if there had been a return statement, there would
6759 have either been a return rtx, or a jump to the return label.
6761 We delay actual code generation after the current_function_value_rtx
6763 clobber_after = get_last_insn ();
6765 /* Output the label for the actual return from the function,
6766 if one is expected. This happens either because a function epilogue
6767 is used instead of a return instruction, or because a return was done
6768 with a goto in order to run local cleanups, or because of pcc-style
6769 structure returning. */
6771 emit_label (return_label);
6773 /* Let except.c know where it should emit the call to unregister
6774 the function context for sjlj exceptions. */
6775 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
6776 sjlj_emit_function_exit_after (get_last_insn ());
6778 /* If we had calls to alloca, and this machine needs
6779 an accurate stack pointer to exit the function,
6780 insert some code to save and restore the stack pointer. */
6781 if (! EXIT_IGNORE_STACK
6782 && current_function_calls_alloca)
6786 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
6787 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
6790 /* If scalar return value was computed in a pseudo-reg, or was a named
6791 return value that got dumped to the stack, copy that to the hard
6793 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6795 tree decl_result = DECL_RESULT (current_function_decl);
6796 rtx decl_rtl = DECL_RTL (decl_result);
6798 if (REG_P (decl_rtl)
6799 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
6800 : DECL_REGISTER (decl_result))
6802 rtx real_decl_rtl = current_function_return_rtx;
6804 /* This should be set in assign_parms. */
6805 if (! REG_FUNCTION_VALUE_P (real_decl_rtl))
6808 /* If this is a BLKmode structure being returned in registers,
6809 then use the mode computed in expand_return. Note that if
6810 decl_rtl is memory, then its mode may have been changed,
6811 but that current_function_return_rtx has not. */
6812 if (GET_MODE (real_decl_rtl) == BLKmode)
6813 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
6815 /* If a named return value dumped decl_return to memory, then
6816 we may need to re-do the PROMOTE_MODE signed/unsigned
6818 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
6820 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (decl_result));
6822 if (targetm.calls.promote_function_return (TREE_TYPE (current_function_decl)))
6823 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
6826 convert_move (real_decl_rtl, decl_rtl, unsignedp);
6828 else if (GET_CODE (real_decl_rtl) == PARALLEL)
6830 /* If expand_function_start has created a PARALLEL for decl_rtl,
6831 move the result to the real return registers. Otherwise, do
6832 a group load from decl_rtl for a named return. */
6833 if (GET_CODE (decl_rtl) == PARALLEL)
6834 emit_group_move (real_decl_rtl, decl_rtl);
6836 emit_group_load (real_decl_rtl, decl_rtl,
6837 TREE_TYPE (decl_result),
6838 int_size_in_bytes (TREE_TYPE (decl_result)));
6841 emit_move_insn (real_decl_rtl, decl_rtl);
6845 /* If returning a structure, arrange to return the address of the value
6846 in a place where debuggers expect to find it.
6848 If returning a structure PCC style,
6849 the caller also depends on this value.
6850 And current_function_returns_pcc_struct is not necessarily set. */
6851 if (current_function_returns_struct
6852 || current_function_returns_pcc_struct)
6855 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
6856 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
6857 #ifdef FUNCTION_OUTGOING_VALUE
6859 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
6860 current_function_decl);
6863 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
6866 /* Mark this as a function return value so integrate will delete the
6867 assignment and USE below when inlining this function. */
6868 REG_FUNCTION_VALUE_P (outgoing) = 1;
6870 /* The address may be ptr_mode and OUTGOING may be Pmode. */
6871 value_address = convert_memory_address (GET_MODE (outgoing),
6874 emit_move_insn (outgoing, value_address);
6876 /* Show return register used to hold result (in this case the address
6878 current_function_return_rtx = outgoing;
6881 /* If this is an implementation of throw, do what's necessary to
6882 communicate between __builtin_eh_return and the epilogue. */
6883 expand_eh_return ();
6885 /* Emit the actual code to clobber return register. */
6890 clobber_return_register ();
6894 after = emit_insn_after (seq, clobber_after);
6897 /* Output the label for the naked return from the function, if one is
6898 expected. This is currently used only by __builtin_return. */
6899 if (naked_return_label)
6900 emit_label (naked_return_label);
6902 /* ??? This should no longer be necessary since stupid is no longer with
6903 us, but there are some parts of the compiler (eg reload_combine, and
6904 sh mach_dep_reorg) that still try and compute their own lifetime info
6905 instead of using the general framework. */
6906 use_return_register ();
6908 /* Fix up any gotos that jumped out to the outermost
6909 binding level of the function.
6910 Must follow emitting RETURN_LABEL. */
6912 /* If you have any cleanups to do at this point,
6913 and they need to create temporary variables,
6914 then you will lose. */
6915 expand_fixups (get_insns ());
6919 get_arg_pointer_save_area (struct function *f)
6921 rtx ret = f->x_arg_pointer_save_area;
6925 ret = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, f);
6926 f->x_arg_pointer_save_area = ret;
6929 if (f == cfun && ! f->arg_pointer_save_area_init)
6933 /* Save the arg pointer at the beginning of the function. The
6934 generated stack slot may not be a valid memory address, so we
6935 have to check it and fix it if necessary. */
6937 emit_move_insn (validize_mem (ret), virtual_incoming_args_rtx);
6941 push_topmost_sequence ();
6942 emit_insn_after (seq, get_insns ());
6943 pop_topmost_sequence ();
6949 /* Extend a vector that records the INSN_UIDs of INSNS
6950 (a list of one or more insns). */
6953 record_insns (rtx insns, varray_type *vecp)
6960 while (tmp != NULL_RTX)
6963 tmp = NEXT_INSN (tmp);
6966 i = VARRAY_SIZE (*vecp);
6967 VARRAY_GROW (*vecp, i + len);
6969 while (tmp != NULL_RTX)
6971 VARRAY_INT (*vecp, i) = INSN_UID (tmp);
6973 tmp = NEXT_INSN (tmp);
6977 /* Set the locator of the insn chain starting at INSN to LOC. */
6979 set_insn_locators (rtx insn, int loc)
6981 while (insn != NULL_RTX)
6984 INSN_LOCATOR (insn) = loc;
6985 insn = NEXT_INSN (insn);
6989 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
6990 be running after reorg, SEQUENCE rtl is possible. */
6993 contains (rtx insn, varray_type vec)
6997 if (GET_CODE (insn) == INSN
6998 && GET_CODE (PATTERN (insn)) == SEQUENCE)
7001 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
7002 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7003 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
7009 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7010 if (INSN_UID (insn) == VARRAY_INT (vec, j))
7017 prologue_epilogue_contains (rtx insn)
7019 if (contains (insn, prologue))
7021 if (contains (insn, epilogue))
7027 sibcall_epilogue_contains (rtx insn)
7029 if (sibcall_epilogue)
7030 return contains (insn, sibcall_epilogue);
7035 /* Insert gen_return at the end of block BB. This also means updating
7036 block_for_insn appropriately. */
7039 emit_return_into_block (basic_block bb, rtx line_note)
7041 emit_jump_insn_after (gen_return (), BB_END (bb));
7043 emit_note_copy_after (line_note, PREV_INSN (BB_END (bb)));
7045 #endif /* HAVE_return */
7047 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
7049 /* These functions convert the epilogue into a variant that does not modify the
7050 stack pointer. This is used in cases where a function returns an object
7051 whose size is not known until it is computed. The called function leaves the
7052 object on the stack, leaves the stack depressed, and returns a pointer to
7055 What we need to do is track all modifications and references to the stack
7056 pointer, deleting the modifications and changing the references to point to
7057 the location the stack pointer would have pointed to had the modifications
7060 These functions need to be portable so we need to make as few assumptions
7061 about the epilogue as we can. However, the epilogue basically contains
7062 three things: instructions to reset the stack pointer, instructions to
7063 reload registers, possibly including the frame pointer, and an
7064 instruction to return to the caller.
7066 If we can't be sure of what a relevant epilogue insn is doing, we abort.
7067 We also make no attempt to validate the insns we make since if they are
7068 invalid, we probably can't do anything valid. The intent is that these
7069 routines get "smarter" as more and more machines start to use them and
7070 they try operating on different epilogues.
7072 We use the following structure to track what the part of the epilogue that
7073 we've already processed has done. We keep two copies of the SP equivalence,
7074 one for use during the insn we are processing and one for use in the next
7075 insn. The difference is because one part of a PARALLEL may adjust SP
7076 and the other may use it. */
7080 rtx sp_equiv_reg; /* REG that SP is set from, perhaps SP. */
7081 HOST_WIDE_INT sp_offset; /* Offset from SP_EQUIV_REG of present SP. */
7082 rtx new_sp_equiv_reg; /* REG to be used at end of insn. */
7083 HOST_WIDE_INT new_sp_offset; /* Offset to be used at end of insn. */
7084 rtx equiv_reg_src; /* If nonzero, the value that SP_EQUIV_REG
7085 should be set to once we no longer need
7087 rtx const_equiv[FIRST_PSEUDO_REGISTER]; /* Any known constant equivalences
7091 static void handle_epilogue_set (rtx, struct epi_info *);
7092 static void update_epilogue_consts (rtx, rtx, void *);
7093 static void emit_equiv_load (struct epi_info *);
7095 /* Modify INSN, a list of one or more insns that is part of the epilogue, to
7096 no modifications to the stack pointer. Return the new list of insns. */
7099 keep_stack_depressed (rtx insns)
7102 struct epi_info info;
7105 /* If the epilogue is just a single instruction, it must be OK as is. */
7106 if (NEXT_INSN (insns) == NULL_RTX)
7109 /* Otherwise, start a sequence, initialize the information we have, and
7110 process all the insns we were given. */
7113 info.sp_equiv_reg = stack_pointer_rtx;
7115 info.equiv_reg_src = 0;
7117 for (j = 0; j < FIRST_PSEUDO_REGISTER; j++)
7118 info.const_equiv[j] = 0;
7122 while (insn != NULL_RTX)
7124 next = NEXT_INSN (insn);
7133 /* If this insn references the register that SP is equivalent to and
7134 we have a pending load to that register, we must force out the load
7135 first and then indicate we no longer know what SP's equivalent is. */
7136 if (info.equiv_reg_src != 0
7137 && reg_referenced_p (info.sp_equiv_reg, PATTERN (insn)))
7139 emit_equiv_load (&info);
7140 info.sp_equiv_reg = 0;
7143 info.new_sp_equiv_reg = info.sp_equiv_reg;
7144 info.new_sp_offset = info.sp_offset;
7146 /* If this is a (RETURN) and the return address is on the stack,
7147 update the address and change to an indirect jump. */
7148 if (GET_CODE (PATTERN (insn)) == RETURN
7149 || (GET_CODE (PATTERN (insn)) == PARALLEL
7150 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == RETURN))
7152 rtx retaddr = INCOMING_RETURN_ADDR_RTX;
7154 HOST_WIDE_INT offset = 0;
7155 rtx jump_insn, jump_set;
7157 /* If the return address is in a register, we can emit the insn
7158 unchanged. Otherwise, it must be a MEM and we see what the
7159 base register and offset are. In any case, we have to emit any
7160 pending load to the equivalent reg of SP, if any. */
7161 if (REG_P (retaddr))
7163 emit_equiv_load (&info);
7168 else if (GET_CODE (retaddr) == MEM
7169 && REG_P (XEXP (retaddr, 0)))
7170 base = gen_rtx_REG (Pmode, REGNO (XEXP (retaddr, 0))), offset = 0;
7171 else if (GET_CODE (retaddr) == MEM
7172 && GET_CODE (XEXP (retaddr, 0)) == PLUS
7173 && REG_P (XEXP (XEXP (retaddr, 0), 0))
7174 && GET_CODE (XEXP (XEXP (retaddr, 0), 1)) == CONST_INT)
7176 base = gen_rtx_REG (Pmode, REGNO (XEXP (XEXP (retaddr, 0), 0)));
7177 offset = INTVAL (XEXP (XEXP (retaddr, 0), 1));
7182 /* If the base of the location containing the return pointer
7183 is SP, we must update it with the replacement address. Otherwise,
7184 just build the necessary MEM. */
7185 retaddr = plus_constant (base, offset);
7186 if (base == stack_pointer_rtx)
7187 retaddr = simplify_replace_rtx (retaddr, stack_pointer_rtx,
7188 plus_constant (info.sp_equiv_reg,
7191 retaddr = gen_rtx_MEM (Pmode, retaddr);
7193 /* If there is a pending load to the equivalent register for SP
7194 and we reference that register, we must load our address into
7195 a scratch register and then do that load. */
7196 if (info.equiv_reg_src
7197 && reg_overlap_mentioned_p (info.equiv_reg_src, retaddr))
7202 for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
7203 if (HARD_REGNO_MODE_OK (regno, Pmode)
7204 && !fixed_regs[regno]
7205 && TEST_HARD_REG_BIT (regs_invalidated_by_call, regno)
7206 && !REGNO_REG_SET_P (EXIT_BLOCK_PTR->global_live_at_start,
7208 && !refers_to_regno_p (regno,
7209 regno + hard_regno_nregs[regno]
7211 info.equiv_reg_src, NULL)
7212 && info.const_equiv[regno] == 0)
7215 if (regno == FIRST_PSEUDO_REGISTER)
7218 reg = gen_rtx_REG (Pmode, regno);
7219 emit_move_insn (reg, retaddr);
7223 emit_equiv_load (&info);
7224 jump_insn = emit_jump_insn (gen_indirect_jump (retaddr));
7226 /* Show the SET in the above insn is a RETURN. */
7227 jump_set = single_set (jump_insn);
7231 SET_IS_RETURN_P (jump_set) = 1;
7234 /* If SP is not mentioned in the pattern and its equivalent register, if
7235 any, is not modified, just emit it. Otherwise, if neither is set,
7236 replace the reference to SP and emit the insn. If none of those are
7237 true, handle each SET individually. */
7238 else if (!reg_mentioned_p (stack_pointer_rtx, PATTERN (insn))
7239 && (info.sp_equiv_reg == stack_pointer_rtx
7240 || !reg_set_p (info.sp_equiv_reg, insn)))
7242 else if (! reg_set_p (stack_pointer_rtx, insn)
7243 && (info.sp_equiv_reg == stack_pointer_rtx
7244 || !reg_set_p (info.sp_equiv_reg, insn)))
7246 if (! validate_replace_rtx (stack_pointer_rtx,
7247 plus_constant (info.sp_equiv_reg,
7254 else if (GET_CODE (PATTERN (insn)) == SET)
7255 handle_epilogue_set (PATTERN (insn), &info);
7256 else if (GET_CODE (PATTERN (insn)) == PARALLEL)
7258 for (j = 0; j < XVECLEN (PATTERN (insn), 0); j++)
7259 if (GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET)
7260 handle_epilogue_set (XVECEXP (PATTERN (insn), 0, j), &info);
7265 info.sp_equiv_reg = info.new_sp_equiv_reg;
7266 info.sp_offset = info.new_sp_offset;
7268 /* Now update any constants this insn sets. */
7269 note_stores (PATTERN (insn), update_epilogue_consts, &info);
7273 insns = get_insns ();
7278 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
7279 structure that contains information about what we've seen so far. We
7280 process this SET by either updating that data or by emitting one or
7284 handle_epilogue_set (rtx set, struct epi_info *p)
7286 /* First handle the case where we are setting SP. Record what it is being
7287 set from. If unknown, abort. */
7288 if (reg_set_p (stack_pointer_rtx, set))
7290 if (SET_DEST (set) != stack_pointer_rtx)
7293 if (GET_CODE (SET_SRC (set)) == PLUS)
7295 p->new_sp_equiv_reg = XEXP (SET_SRC (set), 0);
7296 if (GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT)
7297 p->new_sp_offset = INTVAL (XEXP (SET_SRC (set), 1));
7298 else if (REG_P (XEXP (SET_SRC (set), 1))
7299 && REGNO (XEXP (SET_SRC (set), 1)) < FIRST_PSEUDO_REGISTER
7300 && p->const_equiv[REGNO (XEXP (SET_SRC (set), 1))] != 0)
7302 = INTVAL (p->const_equiv[REGNO (XEXP (SET_SRC (set), 1))]);
7307 p->new_sp_equiv_reg = SET_SRC (set), p->new_sp_offset = 0;
7309 /* If we are adjusting SP, we adjust from the old data. */
7310 if (p->new_sp_equiv_reg == stack_pointer_rtx)
7312 p->new_sp_equiv_reg = p->sp_equiv_reg;
7313 p->new_sp_offset += p->sp_offset;
7316 if (p->new_sp_equiv_reg == 0 || !REG_P (p->new_sp_equiv_reg))
7322 /* Next handle the case where we are setting SP's equivalent register.
7323 If we already have a value to set it to, abort. We could update, but
7324 there seems little point in handling that case. Note that we have
7325 to allow for the case where we are setting the register set in
7326 the previous part of a PARALLEL inside a single insn. But use the
7327 old offset for any updates within this insn. We must allow for the case
7328 where the register is being set in a different (usually wider) mode than
7330 else if (p->new_sp_equiv_reg != 0 && reg_set_p (p->new_sp_equiv_reg, set))
7332 if (p->equiv_reg_src != 0
7333 || !REG_P (p->new_sp_equiv_reg)
7334 || !REG_P (SET_DEST (set))
7335 || GET_MODE_BITSIZE (GET_MODE (SET_DEST (set))) > BITS_PER_WORD
7336 || REGNO (p->new_sp_equiv_reg) != REGNO (SET_DEST (set)))
7340 = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7341 plus_constant (p->sp_equiv_reg,
7345 /* Otherwise, replace any references to SP in the insn to its new value
7346 and emit the insn. */
7349 SET_SRC (set) = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7350 plus_constant (p->sp_equiv_reg,
7352 SET_DEST (set) = simplify_replace_rtx (SET_DEST (set), stack_pointer_rtx,
7353 plus_constant (p->sp_equiv_reg,
7359 /* Update the tracking information for registers set to constants. */
7362 update_epilogue_consts (rtx dest, rtx x, void *data)
7364 struct epi_info *p = (struct epi_info *) data;
7367 if (!REG_P (dest) || REGNO (dest) >= FIRST_PSEUDO_REGISTER)
7370 /* If we are either clobbering a register or doing a partial set,
7371 show we don't know the value. */
7372 else if (GET_CODE (x) == CLOBBER || ! rtx_equal_p (dest, SET_DEST (x)))
7373 p->const_equiv[REGNO (dest)] = 0;
7375 /* If we are setting it to a constant, record that constant. */
7376 else if (GET_CODE (SET_SRC (x)) == CONST_INT)
7377 p->const_equiv[REGNO (dest)] = SET_SRC (x);
7379 /* If this is a binary operation between a register we have been tracking
7380 and a constant, see if we can compute a new constant value. */
7381 else if (ARITHMETIC_P (SET_SRC (x))
7382 && REG_P (XEXP (SET_SRC (x), 0))
7383 && REGNO (XEXP (SET_SRC (x), 0)) < FIRST_PSEUDO_REGISTER
7384 && p->const_equiv[REGNO (XEXP (SET_SRC (x), 0))] != 0
7385 && GET_CODE (XEXP (SET_SRC (x), 1)) == CONST_INT
7386 && 0 != (new = simplify_binary_operation
7387 (GET_CODE (SET_SRC (x)), GET_MODE (dest),
7388 p->const_equiv[REGNO (XEXP (SET_SRC (x), 0))],
7389 XEXP (SET_SRC (x), 1)))
7390 && GET_CODE (new) == CONST_INT)
7391 p->const_equiv[REGNO (dest)] = new;
7393 /* Otherwise, we can't do anything with this value. */
7395 p->const_equiv[REGNO (dest)] = 0;
7398 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
7401 emit_equiv_load (struct epi_info *p)
7403 if (p->equiv_reg_src != 0)
7405 rtx dest = p->sp_equiv_reg;
7407 if (GET_MODE (p->equiv_reg_src) != GET_MODE (dest))
7408 dest = gen_rtx_REG (GET_MODE (p->equiv_reg_src),
7409 REGNO (p->sp_equiv_reg));
7411 emit_move_insn (dest, p->equiv_reg_src);
7412 p->equiv_reg_src = 0;
7417 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7418 this into place with notes indicating where the prologue ends and where
7419 the epilogue begins. Update the basic block information when possible. */
7422 thread_prologue_and_epilogue_insns (rtx f ATTRIBUTE_UNUSED)
7426 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
7429 #ifdef HAVE_prologue
7430 rtx prologue_end = NULL_RTX;
7432 #if defined (HAVE_epilogue) || defined(HAVE_return)
7433 rtx epilogue_end = NULL_RTX;
7436 #ifdef HAVE_prologue
7440 seq = gen_prologue ();
7443 /* Retain a map of the prologue insns. */
7444 record_insns (seq, &prologue);
7445 prologue_end = emit_note (NOTE_INSN_PROLOGUE_END);
7449 set_insn_locators (seq, prologue_locator);
7451 /* Can't deal with multiple successors of the entry block
7452 at the moment. Function should always have at least one
7454 if (!ENTRY_BLOCK_PTR->succ || ENTRY_BLOCK_PTR->succ->succ_next)
7457 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
7462 /* If the exit block has no non-fake predecessors, we don't need
7464 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7465 if ((e->flags & EDGE_FAKE) == 0)
7471 if (optimize && HAVE_return)
7473 /* If we're allowed to generate a simple return instruction,
7474 then by definition we don't need a full epilogue. Examine
7475 the block that falls through to EXIT. If it does not
7476 contain any code, examine its predecessors and try to
7477 emit (conditional) return instructions. */
7483 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7484 if (e->flags & EDGE_FALLTHRU)
7490 /* Verify that there are no active instructions in the last block. */
7491 label = BB_END (last);
7492 while (label && GET_CODE (label) != CODE_LABEL)
7494 if (active_insn_p (label))
7496 label = PREV_INSN (label);
7499 if (BB_HEAD (last) == label && GET_CODE (label) == CODE_LABEL)
7501 rtx epilogue_line_note = NULL_RTX;
7503 /* Locate the line number associated with the closing brace,
7504 if we can find one. */
7505 for (seq = get_last_insn ();
7506 seq && ! active_insn_p (seq);
7507 seq = PREV_INSN (seq))
7508 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
7510 epilogue_line_note = seq;
7514 for (e = last->pred; e; e = e_next)
7516 basic_block bb = e->src;
7519 e_next = e->pred_next;
7520 if (bb == ENTRY_BLOCK_PTR)
7524 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
7527 /* If we have an unconditional jump, we can replace that
7528 with a simple return instruction. */
7529 if (simplejump_p (jump))
7531 emit_return_into_block (bb, epilogue_line_note);
7535 /* If we have a conditional jump, we can try to replace
7536 that with a conditional return instruction. */
7537 else if (condjump_p (jump))
7539 if (! redirect_jump (jump, 0, 0))
7542 /* If this block has only one successor, it both jumps
7543 and falls through to the fallthru block, so we can't
7545 if (bb->succ->succ_next == NULL)
7551 /* Fix up the CFG for the successful change we just made. */
7552 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7555 /* Emit a return insn for the exit fallthru block. Whether
7556 this is still reachable will be determined later. */
7558 emit_barrier_after (BB_END (last));
7559 emit_return_into_block (last, epilogue_line_note);
7560 epilogue_end = BB_END (last);
7561 last->succ->flags &= ~EDGE_FALLTHRU;
7566 /* Find the edge that falls through to EXIT. Other edges may exist
7567 due to RETURN instructions, but those don't need epilogues.
7568 There really shouldn't be a mixture -- either all should have
7569 been converted or none, however... */
7571 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7572 if (e->flags & EDGE_FALLTHRU)
7577 #ifdef HAVE_epilogue
7581 epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG);
7583 seq = gen_epilogue ();
7585 #ifdef INCOMING_RETURN_ADDR_RTX
7586 /* If this function returns with the stack depressed and we can support
7587 it, massage the epilogue to actually do that. */
7588 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7589 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7590 seq = keep_stack_depressed (seq);
7593 emit_jump_insn (seq);
7595 /* Retain a map of the epilogue insns. */
7596 record_insns (seq, &epilogue);
7597 set_insn_locators (seq, epilogue_locator);
7602 insert_insn_on_edge (seq, e);
7610 if (! next_active_insn (BB_END (e->src)))
7612 /* We have a fall-through edge to the exit block, the source is not
7613 at the end of the function, and there will be an assembler epilogue
7614 at the end of the function.
7615 We can't use force_nonfallthru here, because that would try to
7616 use return. Inserting a jump 'by hand' is extremely messy, so
7617 we take advantage of cfg_layout_finalize using
7618 fixup_fallthru_exit_predecessor. */
7619 cfg_layout_initialize ();
7620 FOR_EACH_BB (cur_bb)
7621 if (cur_bb->index >= 0 && cur_bb->next_bb->index >= 0)
7622 cur_bb->rbi->next = cur_bb->next_bb;
7623 cfg_layout_finalize ();
7628 commit_edge_insertions ();
7630 #ifdef HAVE_sibcall_epilogue
7631 /* Emit sibling epilogues before any sibling call sites. */
7632 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7634 basic_block bb = e->src;
7635 rtx insn = BB_END (bb);
7639 if (GET_CODE (insn) != CALL_INSN
7640 || ! SIBLING_CALL_P (insn))
7644 emit_insn (gen_sibcall_epilogue ());
7648 /* Retain a map of the epilogue insns. Used in life analysis to
7649 avoid getting rid of sibcall epilogue insns. Do this before we
7650 actually emit the sequence. */
7651 record_insns (seq, &sibcall_epilogue);
7652 set_insn_locators (seq, epilogue_locator);
7654 i = PREV_INSN (insn);
7655 newinsn = emit_insn_before (seq, insn);
7659 #ifdef HAVE_prologue
7660 /* This is probably all useless now that we use locators. */
7665 /* GDB handles `break f' by setting a breakpoint on the first
7666 line note after the prologue. Which means (1) that if
7667 there are line number notes before where we inserted the
7668 prologue we should move them, and (2) we should generate a
7669 note before the end of the first basic block, if there isn't
7672 ??? This behavior is completely broken when dealing with
7673 multiple entry functions. We simply place the note always
7674 into first basic block and let alternate entry points
7678 for (insn = prologue_end; insn; insn = prev)
7680 prev = PREV_INSN (insn);
7681 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7683 /* Note that we cannot reorder the first insn in the
7684 chain, since rest_of_compilation relies on that
7685 remaining constant. */
7688 reorder_insns (insn, insn, prologue_end);
7692 /* Find the last line number note in the first block. */
7693 for (insn = BB_END (ENTRY_BLOCK_PTR->next_bb);
7694 insn != prologue_end && insn;
7695 insn = PREV_INSN (insn))
7696 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7699 /* If we didn't find one, make a copy of the first line number
7703 for (insn = next_active_insn (prologue_end);
7705 insn = PREV_INSN (insn))
7706 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7708 emit_note_copy_after (insn, prologue_end);
7714 #ifdef HAVE_epilogue
7719 /* Similarly, move any line notes that appear after the epilogue.
7720 There is no need, however, to be quite so anal about the existence
7721 of such a note. Also move the NOTE_INSN_FUNCTION_END and (possibly)
7722 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
7724 for (insn = epilogue_end; insn; insn = next)
7726 next = NEXT_INSN (insn);
7727 if (GET_CODE (insn) == NOTE
7728 && (NOTE_LINE_NUMBER (insn) > 0
7729 || NOTE_LINE_NUMBER (insn) == NOTE_INSN_FUNCTION_BEG
7730 || NOTE_LINE_NUMBER (insn) == NOTE_INSN_FUNCTION_END))
7731 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7737 /* Reposition the prologue-end and epilogue-begin notes after instruction
7738 scheduling and delayed branch scheduling. */
7741 reposition_prologue_and_epilogue_notes (rtx f ATTRIBUTE_UNUSED)
7743 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7744 rtx insn, last, note;
7747 if ((len = VARRAY_SIZE (prologue)) > 0)
7751 /* Scan from the beginning until we reach the last prologue insn.
7752 We apparently can't depend on basic_block_{head,end} after
7754 for (insn = f; insn; insn = NEXT_INSN (insn))
7756 if (GET_CODE (insn) == NOTE)
7758 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
7761 else if (contains (insn, prologue))
7771 /* Find the prologue-end note if we haven't already, and
7772 move it to just after the last prologue insn. */
7775 for (note = last; (note = NEXT_INSN (note));)
7776 if (GET_CODE (note) == NOTE
7777 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
7781 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
7782 if (GET_CODE (last) == CODE_LABEL)
7783 last = NEXT_INSN (last);
7784 reorder_insns (note, note, last);
7788 if ((len = VARRAY_SIZE (epilogue)) > 0)
7792 /* Scan from the end until we reach the first epilogue insn.
7793 We apparently can't depend on basic_block_{head,end} after
7795 for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
7797 if (GET_CODE (insn) == NOTE)
7799 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
7802 else if (contains (insn, epilogue))
7812 /* Find the epilogue-begin note if we haven't already, and
7813 move it to just before the first epilogue insn. */
7816 for (note = insn; (note = PREV_INSN (note));)
7817 if (GET_CODE (note) == NOTE
7818 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
7822 if (PREV_INSN (last) != note)
7823 reorder_insns (note, note, PREV_INSN (last));
7826 #endif /* HAVE_prologue or HAVE_epilogue */
7829 /* Called once, at initialization, to initialize function.c. */
7832 init_function_once (void)
7834 VARRAY_INT_INIT (prologue, 0, "prologue");
7835 VARRAY_INT_INIT (epilogue, 0, "epilogue");
7836 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");
7839 /* Resets insn_block_boundaries array. */
7842 reset_block_changes (void)
7844 VARRAY_TREE_INIT (cfun->ib_boundaries_block, 100, "ib_boundaries_block");
7845 VARRAY_PUSH_TREE (cfun->ib_boundaries_block, NULL_TREE);
7848 /* Record the boundary for BLOCK. */
7850 record_block_change (tree block)
7858 last_block = VARRAY_TOP_TREE (cfun->ib_boundaries_block);
7859 VARRAY_POP (cfun->ib_boundaries_block);
7861 for (i = VARRAY_ACTIVE_SIZE (cfun->ib_boundaries_block); i < n; i++)
7862 VARRAY_PUSH_TREE (cfun->ib_boundaries_block, last_block);
7864 VARRAY_PUSH_TREE (cfun->ib_boundaries_block, block);
7867 /* Finishes record of boundaries. */
7868 void finalize_block_changes (void)
7870 record_block_change (DECL_INITIAL (current_function_decl));
7873 /* For INSN return the BLOCK it belongs to. */
7875 check_block_change (rtx insn, tree *block)
7877 unsigned uid = INSN_UID (insn);
7879 if (uid >= VARRAY_ACTIVE_SIZE (cfun->ib_boundaries_block))
7882 *block = VARRAY_TREE (cfun->ib_boundaries_block, uid);
7885 /* Releases the ib_boundaries_block records. */
7887 free_block_changes (void)
7889 cfun->ib_boundaries_block = NULL;
7892 /* Returns the name of the current function. */
7894 current_function_name (void)
7896 return lang_hooks.decl_printable_name (cfun->decl, 2);
7899 #include "gt-function.h"