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 the first insn following those generated by `assign_parms'. */
4217 get_first_nonparm_insn (void)
4220 return NEXT_INSN (last_parm_insn);
4221 return get_insns ();
4224 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4225 This means a type for which function calls must pass an address to the
4226 function or get an address back from the function.
4227 EXP may be a type node or an expression (whose type is tested). */
4230 aggregate_value_p (tree exp, tree fntype)
4232 int i, regno, nregs;
4235 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4238 switch (TREE_CODE (fntype))
4241 fntype = get_callee_fndecl (fntype);
4242 fntype = fntype ? TREE_TYPE (fntype) : 0;
4245 fntype = TREE_TYPE (fntype);
4250 case IDENTIFIER_NODE:
4254 /* We don't expect other rtl types here. */
4258 if (TREE_CODE (type) == VOID_TYPE)
4260 if (targetm.calls.return_in_memory (type, fntype))
4262 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4263 and thus can't be returned in registers. */
4264 if (TREE_ADDRESSABLE (type))
4266 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4268 /* Make sure we have suitable call-clobbered regs to return
4269 the value in; if not, we must return it in memory. */
4270 reg = hard_function_value (type, 0, 0);
4272 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4277 regno = REGNO (reg);
4278 nregs = hard_regno_nregs[regno][TYPE_MODE (type)];
4279 for (i = 0; i < nregs; i++)
4280 if (! call_used_regs[regno + i])
4285 /* Assign RTL expressions to the function's parameters.
4286 This may involve copying them into registers and using
4287 those registers as the RTL for them. */
4290 assign_parms (tree fndecl)
4293 CUMULATIVE_ARGS args_so_far;
4294 /* Total space needed so far for args on the stack,
4295 given as a constant and a tree-expression. */
4296 struct args_size stack_args_size;
4297 HOST_WIDE_INT extra_pretend_bytes = 0;
4298 tree fntype = TREE_TYPE (fndecl);
4299 tree fnargs = DECL_ARGUMENTS (fndecl), orig_fnargs;
4300 /* This is used for the arg pointer when referring to stack args. */
4301 rtx internal_arg_pointer;
4302 /* This is a dummy PARM_DECL that we used for the function result if
4303 the function returns a structure. */
4304 tree function_result_decl = 0;
4305 int varargs_setup = 0;
4306 int reg_parm_stack_space ATTRIBUTE_UNUSED = 0;
4307 rtx conversion_insns = 0;
4309 /* Nonzero if function takes extra anonymous args.
4310 This means the last named arg must be on the stack
4311 right before the anonymous ones. */
4312 int stdarg = current_function_stdarg;
4314 /* If the reg that the virtual arg pointer will be translated into is
4315 not a fixed reg or is the stack pointer, make a copy of the virtual
4316 arg pointer, and address parms via the copy. The frame pointer is
4317 considered fixed even though it is not marked as such.
4319 The second time through, simply use ap to avoid generating rtx. */
4321 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4322 || ! (fixed_regs[ARG_POINTER_REGNUM]
4323 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4324 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4326 internal_arg_pointer = virtual_incoming_args_rtx;
4327 current_function_internal_arg_pointer = internal_arg_pointer;
4329 stack_args_size.constant = 0;
4330 stack_args_size.var = 0;
4332 /* If struct value address is treated as the first argument, make it so. */
4333 if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
4334 && ! current_function_returns_pcc_struct
4335 && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
4337 tree type = build_pointer_type (TREE_TYPE (fntype));
4339 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4341 DECL_ARG_TYPE (function_result_decl) = type;
4342 TREE_CHAIN (function_result_decl) = fnargs;
4343 fnargs = function_result_decl;
4346 orig_fnargs = fnargs;
4348 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4349 parm_reg_stack_loc = ggc_alloc_cleared (max_parm_reg * sizeof (rtx));
4351 /* If the target wants to split complex arguments into scalars, do so. */
4352 if (targetm.calls.split_complex_arg)
4353 fnargs = split_complex_args (fnargs);
4355 #ifdef REG_PARM_STACK_SPACE
4356 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
4359 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4360 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4362 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, fndecl, -1);
4365 /* We haven't yet found an argument that we must push and pretend the
4367 current_function_pretend_args_size = 0;
4369 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4373 enum machine_mode promoted_mode, passed_mode;
4374 enum machine_mode nominal_mode, promoted_nominal_mode;
4376 struct locate_and_pad_arg_data locate;
4377 int passed_pointer = 0;
4378 int did_conversion = 0;
4379 tree passed_type = DECL_ARG_TYPE (parm);
4380 tree nominal_type = TREE_TYPE (parm);
4381 int last_named = 0, named_arg;
4384 int pretend_bytes = 0;
4385 int loaded_in_reg = 0;
4387 /* Set LAST_NAMED if this is last named arg before last
4393 for (tem = TREE_CHAIN (parm); tem; tem = TREE_CHAIN (tem))
4394 if (DECL_NAME (tem))
4400 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4401 most machines, if this is a varargs/stdarg function, then we treat
4402 the last named arg as if it were anonymous too. */
4403 named_arg = (targetm.calls.strict_argument_naming (&args_so_far)
4406 if (TREE_TYPE (parm) == error_mark_node
4407 /* This can happen after weird syntax errors
4408 or if an enum type is defined among the parms. */
4409 || TREE_CODE (parm) != PARM_DECL
4410 || passed_type == NULL)
4412 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx));
4413 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4414 TREE_USED (parm) = 1;
4418 /* Find mode of arg as it is passed, and mode of arg
4419 as it should be during execution of this function. */
4420 passed_mode = TYPE_MODE (passed_type);
4421 nominal_mode = TYPE_MODE (nominal_type);
4423 /* If the parm's mode is VOID, its value doesn't matter,
4424 and avoid the usual things like emit_move_insn that could crash. */
4425 if (nominal_mode == VOIDmode)
4427 SET_DECL_RTL (parm, const0_rtx);
4428 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4432 /* If the parm is to be passed as a transparent union, use the
4433 type of the first field for the tests below. We have already
4434 verified that the modes are the same. */
4435 if (DECL_TRANSPARENT_UNION (parm)
4436 || (TREE_CODE (passed_type) == UNION_TYPE
4437 && TYPE_TRANSPARENT_UNION (passed_type)))
4438 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4440 /* See if this arg was passed by invisible reference. It is if
4441 it is an object whose size depends on the contents of the
4442 object itself or if the machine requires these objects be passed
4445 if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE (passed_type))
4446 || TREE_ADDRESSABLE (passed_type)
4447 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4448 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4449 passed_type, named_arg)
4453 passed_type = nominal_type = build_pointer_type (passed_type);
4455 passed_mode = nominal_mode = Pmode;
4457 /* See if the frontend wants to pass this by invisible reference. */
4458 else if (passed_type != nominal_type
4459 && POINTER_TYPE_P (passed_type)
4460 && TREE_TYPE (passed_type) == nominal_type)
4462 nominal_type = passed_type;
4464 passed_mode = nominal_mode = Pmode;
4467 promoted_mode = passed_mode;
4469 if (targetm.calls.promote_function_args (TREE_TYPE (fndecl)))
4471 /* Compute the mode in which the arg is actually extended to. */
4472 unsignedp = TYPE_UNSIGNED (passed_type);
4473 promoted_mode = promote_mode (passed_type, promoted_mode,
4477 /* Let machine desc say which reg (if any) the parm arrives in.
4478 0 means it arrives on the stack. */
4479 #ifdef FUNCTION_INCOMING_ARG
4480 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4481 passed_type, named_arg);
4483 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4484 passed_type, named_arg);
4487 if (entry_parm == 0)
4488 promoted_mode = passed_mode;
4490 /* If this is the last named parameter, do any required setup for
4491 varargs or stdargs. We need to know about the case of this being an
4492 addressable type, in which case we skip the registers it
4493 would have arrived in.
4495 For stdargs, LAST_NAMED will be set for two parameters, the one that
4496 is actually the last named, and the dummy parameter. We only
4497 want to do this action once.
4499 Also, indicate when RTL generation is to be suppressed. */
4500 if (last_named && !varargs_setup)
4502 int varargs_pretend_bytes = 0;
4503 targetm.calls.setup_incoming_varargs (&args_so_far, promoted_mode,
4505 &varargs_pretend_bytes, 0);
4508 /* If the back-end has requested extra stack space, record how
4509 much is needed. Do not change pretend_args_size otherwise
4510 since it may be nonzero from an earlier partial argument. */
4511 if (varargs_pretend_bytes > 0)
4512 current_function_pretend_args_size = varargs_pretend_bytes;
4515 /* Determine parm's home in the stack,
4516 in case it arrives in the stack or we should pretend it did.
4518 Compute the stack position and rtx where the argument arrives
4521 There is one complexity here: If this was a parameter that would
4522 have been passed in registers, but wasn't only because it is
4523 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4524 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4525 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4526 0 as it was the previous time. */
4527 in_regs = entry_parm != 0;
4528 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4531 if (!in_regs && !named_arg)
4534 targetm.calls.pretend_outgoing_varargs_named (&args_so_far);
4537 #ifdef FUNCTION_INCOMING_ARG
4538 in_regs = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4540 pretend_named) != 0;
4542 in_regs = FUNCTION_ARG (args_so_far, promoted_mode,
4544 pretend_named) != 0;
4549 /* If this parameter was passed both in registers and in the stack,
4550 use the copy on the stack. */
4551 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4554 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4557 partial = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4558 passed_type, named_arg);
4560 /* The caller might already have allocated stack space
4561 for the register parameters. */
4562 && reg_parm_stack_space == 0)
4564 /* Part of this argument is passed in registers and part
4565 is passed on the stack. Ask the prologue code to extend
4566 the stack part so that we can recreate the full value.
4568 PRETEND_BYTES is the size of the registers we need to store.
4569 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
4570 stack space that the prologue should allocate.
4572 Internally, gcc assumes that the argument pointer is
4573 aligned to STACK_BOUNDARY bits. This is used both for
4574 alignment optimizations (see init_emit) and to locate
4575 arguments that are aligned to more than PARM_BOUNDARY
4576 bits. We must preserve this invariant by rounding
4577 CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to a stack
4580 /* We assume at most one partial arg, and it must be the first
4581 argument on the stack. */
4582 if (extra_pretend_bytes || current_function_pretend_args_size)
4585 pretend_bytes = partial * UNITS_PER_WORD;
4586 current_function_pretend_args_size
4587 = CEIL_ROUND (pretend_bytes, STACK_BYTES);
4589 /* We want to align relative to the actual stack pointer, so
4590 don't include this in the stack size until later. */
4591 extra_pretend_bytes = current_function_pretend_args_size;
4596 memset (&locate, 0, sizeof (locate));
4597 locate_and_pad_parm (promoted_mode, passed_type, in_regs,
4598 entry_parm ? partial : 0, fndecl,
4599 &stack_args_size, &locate);
4600 /* Adjust offsets to include the pretend args. */
4601 locate.slot_offset.constant += extra_pretend_bytes - pretend_bytes;
4602 locate.offset.constant += extra_pretend_bytes - pretend_bytes;
4606 unsigned int align, boundary;
4608 /* If we're passing this arg using a reg, make its stack home
4609 the aligned stack slot. */
4611 offset_rtx = ARGS_SIZE_RTX (locate.slot_offset);
4613 offset_rtx = ARGS_SIZE_RTX (locate.offset);
4615 if (offset_rtx == const0_rtx)
4616 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4618 stack_parm = gen_rtx_MEM (promoted_mode,
4619 gen_rtx_PLUS (Pmode,
4620 internal_arg_pointer,
4623 set_mem_attributes (stack_parm, parm, 1);
4625 boundary = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4628 /* If we're padding upward, we know that the alignment of the slot
4629 is FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
4630 intentionally forcing upward padding. Otherwise we have to come
4631 up with a guess at the alignment based on OFFSET_RTX. */
4632 if (locate.where_pad == upward || entry_parm)
4634 else if (GET_CODE (offset_rtx) == CONST_INT)
4636 align = INTVAL (offset_rtx) * BITS_PER_UNIT | boundary;
4637 align = align & -align;
4640 set_mem_align (stack_parm, align);
4643 set_reg_attrs_for_parm (entry_parm, stack_parm);
4646 /* If this parm was passed part in regs and part in memory,
4647 pretend it arrived entirely in memory
4648 by pushing the register-part onto the stack.
4650 In the special case of a DImode or DFmode that is split,
4651 we could put it together in a pseudoreg directly,
4652 but for now that's not worth bothering with. */
4656 /* Handle calls that pass values in multiple non-contiguous
4657 locations. The Irix 6 ABI has examples of this. */
4658 if (GET_CODE (entry_parm) == PARALLEL)
4659 emit_group_store (validize_mem (stack_parm), entry_parm,
4661 int_size_in_bytes (TREE_TYPE (parm)));
4664 move_block_from_reg (REGNO (entry_parm), validize_mem (stack_parm),
4667 entry_parm = stack_parm;
4670 /* If we didn't decide this parm came in a register,
4671 by default it came on the stack. */
4672 if (entry_parm == 0)
4673 entry_parm = stack_parm;
4675 /* Record permanently how this parm was passed. */
4676 set_decl_incoming_rtl (parm, entry_parm);
4678 /* If there is actually space on the stack for this parm,
4679 count it in stack_args_size; otherwise set stack_parm to 0
4680 to indicate there is no preallocated stack slot for the parm. */
4682 if (entry_parm == stack_parm
4683 || (GET_CODE (entry_parm) == PARALLEL
4684 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4685 #if defined (REG_PARM_STACK_SPACE)
4686 /* On some machines, even if a parm value arrives in a register
4687 there is still an (uninitialized) stack slot allocated
4689 || REG_PARM_STACK_SPACE (fndecl) > 0
4693 stack_args_size.constant += locate.size.constant;
4694 if (locate.size.var)
4695 ADD_PARM_SIZE (stack_args_size, locate.size.var);
4698 /* No stack slot was pushed for this parm. */
4701 /* Update info on where next arg arrives in registers. */
4703 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4704 passed_type, named_arg);
4706 /* If we can't trust the parm stack slot to be aligned enough
4707 for its ultimate type, don't use that slot after entry.
4708 We'll make another stack slot, if we need one. */
4709 if (STRICT_ALIGNMENT && stack_parm
4710 && GET_MODE_ALIGNMENT (nominal_mode) > MEM_ALIGN (stack_parm))
4713 /* If parm was passed in memory, and we need to convert it on entry,
4714 don't store it back in that same slot. */
4715 if (entry_parm == stack_parm
4716 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4719 /* When an argument is passed in multiple locations, we can't
4720 make use of this information, but we can save some copying if
4721 the whole argument is passed in a single register. */
4722 if (GET_CODE (entry_parm) == PARALLEL
4723 && nominal_mode != BLKmode && passed_mode != BLKmode)
4725 int i, len = XVECLEN (entry_parm, 0);
4727 for (i = 0; i < len; i++)
4728 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
4729 && REG_P (XEXP (XVECEXP (entry_parm, 0, i), 0))
4730 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
4732 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
4734 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
4735 set_decl_incoming_rtl (parm, entry_parm);
4740 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4741 in the mode in which it arrives.
4742 STACK_PARM is an RTX for a stack slot where the parameter can live
4743 during the function (in case we want to put it there).
4744 STACK_PARM is 0 if no stack slot was pushed for it.
4746 Now output code if necessary to convert ENTRY_PARM to
4747 the type in which this function declares it,
4748 and store that result in an appropriate place,
4749 which may be a pseudo reg, may be STACK_PARM,
4750 or may be a local stack slot if STACK_PARM is 0.
4752 Set DECL_RTL to that place. */
4754 if (GET_CODE (entry_parm) == PARALLEL && nominal_mode != BLKmode
4755 && XVECLEN (entry_parm, 0) > 1)
4757 /* Reconstitute objects the size of a register or larger using
4758 register operations instead of the stack. */
4759 rtx parmreg = gen_reg_rtx (nominal_mode);
4761 if (REG_P (parmreg))
4763 unsigned int regno = REGNO (parmreg);
4765 emit_group_store (parmreg, entry_parm, TREE_TYPE (parm),
4766 int_size_in_bytes (TREE_TYPE (parm)));
4767 SET_DECL_RTL (parm, parmreg);
4770 if (regno >= max_parm_reg)
4773 int old_max_parm_reg = max_parm_reg;
4775 /* It's slow to expand this one register at a time,
4776 but it's also rare and we need max_parm_reg to be
4777 precisely correct. */
4778 max_parm_reg = regno + 1;
4779 new = ggc_realloc (parm_reg_stack_loc,
4780 max_parm_reg * sizeof (rtx));
4781 memset (new + old_max_parm_reg, 0,
4782 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4783 parm_reg_stack_loc = new;
4784 parm_reg_stack_loc[regno] = stack_parm;
4789 if (nominal_mode == BLKmode
4790 #ifdef BLOCK_REG_PADDING
4791 || (locate.where_pad == (BYTES_BIG_ENDIAN ? upward : downward)
4792 && GET_MODE_SIZE (promoted_mode) < UNITS_PER_WORD)
4794 || GET_CODE (entry_parm) == PARALLEL)
4796 /* If a BLKmode arrives in registers, copy it to a stack slot.
4797 Handle calls that pass values in multiple non-contiguous
4798 locations. The Irix 6 ABI has examples of this. */
4799 if (REG_P (entry_parm)
4800 || (GET_CODE (entry_parm) == PARALLEL
4801 && (!loaded_in_reg || !optimize)))
4803 int size = int_size_in_bytes (TREE_TYPE (parm));
4804 int size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
4807 /* Note that we will be storing an integral number of words.
4808 So we have to be careful to ensure that we allocate an
4809 integral number of words. We do this below in the
4810 assign_stack_local if space was not allocated in the argument
4811 list. If it was, this will not work if PARM_BOUNDARY is not
4812 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4813 if it becomes a problem. Exception is when BLKmode arrives
4814 with arguments not conforming to word_mode. */
4816 if (stack_parm == 0)
4818 stack_parm = assign_stack_local (BLKmode, size_stored, 0);
4819 PUT_MODE (stack_parm, GET_MODE (entry_parm));
4820 set_mem_attributes (stack_parm, parm, 1);
4822 else if (GET_CODE (entry_parm) == PARALLEL)
4824 else if (size != 0 && PARM_BOUNDARY % BITS_PER_WORD != 0)
4827 mem = validize_mem (stack_parm);
4829 /* Handle calls that pass values in multiple non-contiguous
4830 locations. The Irix 6 ABI has examples of this. */
4831 if (GET_CODE (entry_parm) == PARALLEL)
4832 emit_group_store (mem, entry_parm, TREE_TYPE (parm), size);
4837 /* If SIZE is that of a mode no bigger than a word, just use
4838 that mode's store operation. */
4839 else if (size <= UNITS_PER_WORD)
4841 enum machine_mode mode
4842 = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
4845 #ifdef BLOCK_REG_PADDING
4846 && (size == UNITS_PER_WORD
4847 || (BLOCK_REG_PADDING (mode, TREE_TYPE (parm), 1)
4848 != (BYTES_BIG_ENDIAN ? upward : downward)))
4852 rtx reg = gen_rtx_REG (mode, REGNO (entry_parm));
4853 emit_move_insn (change_address (mem, mode, 0), reg);
4856 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
4857 machine must be aligned to the left before storing
4858 to memory. Note that the previous test doesn't
4859 handle all cases (e.g. SIZE == 3). */
4860 else if (size != UNITS_PER_WORD
4861 #ifdef BLOCK_REG_PADDING
4862 && (BLOCK_REG_PADDING (mode, TREE_TYPE (parm), 1)
4870 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
4871 rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
4873 x = expand_binop (word_mode, ashl_optab, reg,
4874 GEN_INT (by), 0, 1, OPTAB_WIDEN);
4875 tem = change_address (mem, word_mode, 0);
4876 emit_move_insn (tem, x);
4879 move_block_from_reg (REGNO (entry_parm), mem,
4880 size_stored / UNITS_PER_WORD);
4883 move_block_from_reg (REGNO (entry_parm), mem,
4884 size_stored / UNITS_PER_WORD);
4886 /* If parm is already bound to register pair, don't change
4888 if (! DECL_RTL_SET_P (parm))
4889 SET_DECL_RTL (parm, stack_parm);
4891 else if (! ((! optimize
4892 && ! DECL_REGISTER (parm))
4893 || TREE_SIDE_EFFECTS (parm)
4894 /* If -ffloat-store specified, don't put explicit
4895 float variables into registers. */
4896 || (flag_float_store
4897 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4898 /* Always assign pseudo to structure return or item passed
4899 by invisible reference. */
4900 || passed_pointer || parm == function_result_decl)
4902 /* Store the parm in a pseudoregister during the function, but we
4903 may need to do it in a wider mode. */
4906 unsigned int regno, regnoi = 0, regnor = 0;
4908 unsignedp = TYPE_UNSIGNED (TREE_TYPE (parm));
4910 promoted_nominal_mode
4911 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4913 parmreg = gen_reg_rtx (promoted_nominal_mode);
4914 mark_user_reg (parmreg);
4916 /* If this was an item that we received a pointer to, set DECL_RTL
4920 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)),
4922 set_mem_attributes (x, parm, 1);
4923 SET_DECL_RTL (parm, x);
4927 SET_DECL_RTL (parm, parmreg);
4928 maybe_set_unchanging (DECL_RTL (parm), parm);
4931 /* Copy the value into the register. */
4932 if (nominal_mode != passed_mode
4933 || promoted_nominal_mode != promoted_mode)
4936 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4937 mode, by the caller. We now have to convert it to
4938 NOMINAL_MODE, if different. However, PARMREG may be in
4939 a different mode than NOMINAL_MODE if it is being stored
4942 If ENTRY_PARM is a hard register, it might be in a register
4943 not valid for operating in its mode (e.g., an odd-numbered
4944 register for a DFmode). In that case, moves are the only
4945 thing valid, so we can't do a convert from there. This
4946 occurs when the calling sequence allow such misaligned
4949 In addition, the conversion may involve a call, which could
4950 clobber parameters which haven't been copied to pseudo
4951 registers yet. Therefore, we must first copy the parm to
4952 a pseudo reg here, and save the conversion until after all
4953 parameters have been moved. */
4955 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4957 emit_move_insn (tempreg, validize_mem (entry_parm));
4959 push_to_sequence (conversion_insns);
4960 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4962 if (GET_CODE (tempreg) == SUBREG
4963 && GET_MODE (tempreg) == nominal_mode
4964 && REG_P (SUBREG_REG (tempreg))
4965 && nominal_mode == passed_mode
4966 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm)
4967 && GET_MODE_SIZE (GET_MODE (tempreg))
4968 < GET_MODE_SIZE (GET_MODE (entry_parm)))
4970 /* The argument is already sign/zero extended, so note it
4972 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
4973 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
4976 /* TREE_USED gets set erroneously during expand_assignment. */
4977 save_tree_used = TREE_USED (parm);
4978 expand_assignment (parm,
4979 make_tree (nominal_type, tempreg), 0);
4980 TREE_USED (parm) = save_tree_used;
4981 conversion_insns = get_insns ();
4986 emit_move_insn (parmreg, validize_mem (entry_parm));
4988 /* If we were passed a pointer but the actual value
4989 can safely live in a register, put it in one. */
4990 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4991 /* If by-reference argument was promoted, demote it. */
4992 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
4994 && ! DECL_REGISTER (parm))
4995 || TREE_SIDE_EFFECTS (parm)
4996 /* If -ffloat-store specified, don't put explicit
4997 float variables into registers. */
4998 || (flag_float_store
4999 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))))
5001 /* We can't use nominal_mode, because it will have been set to
5002 Pmode above. We must use the actual mode of the parm. */
5003 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
5004 mark_user_reg (parmreg);
5005 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
5007 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
5008 int unsigned_p = TYPE_UNSIGNED (TREE_TYPE (parm));
5009 push_to_sequence (conversion_insns);
5010 emit_move_insn (tempreg, DECL_RTL (parm));
5012 convert_to_mode (GET_MODE (parmreg),
5015 emit_move_insn (parmreg, DECL_RTL (parm));
5016 conversion_insns = get_insns();
5021 emit_move_insn (parmreg, DECL_RTL (parm));
5022 SET_DECL_RTL (parm, parmreg);
5023 /* STACK_PARM is the pointer, not the parm, and PARMREG is
5027 #ifdef FUNCTION_ARG_CALLEE_COPIES
5028 /* If we are passed an arg by reference and it is our responsibility
5029 to make a copy, do it now.
5030 PASSED_TYPE and PASSED mode now refer to the pointer, not the
5031 original argument, so we must recreate them in the call to
5032 FUNCTION_ARG_CALLEE_COPIES. */
5033 /* ??? Later add code to handle the case that if the argument isn't
5034 modified, don't do the copy. */
5036 else if (passed_pointer
5037 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
5038 TYPE_MODE (TREE_TYPE (passed_type)),
5039 TREE_TYPE (passed_type),
5041 && ! TREE_ADDRESSABLE (TREE_TYPE (passed_type)))
5044 tree type = TREE_TYPE (passed_type);
5046 /* This sequence may involve a library call perhaps clobbering
5047 registers that haven't been copied to pseudos yet. */
5049 push_to_sequence (conversion_insns);
5051 if (!COMPLETE_TYPE_P (type)
5052 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
5053 /* This is a variable sized object. */
5054 copy = gen_rtx_MEM (BLKmode,
5055 allocate_dynamic_stack_space
5056 (expr_size (parm), NULL_RTX,
5057 TYPE_ALIGN (type)));
5059 copy = assign_stack_temp (TYPE_MODE (type),
5060 int_size_in_bytes (type), 1);
5061 set_mem_attributes (copy, parm, 1);
5063 store_expr (parm, copy, 0);
5064 emit_move_insn (parmreg, XEXP (copy, 0));
5065 conversion_insns = get_insns ();
5069 #endif /* FUNCTION_ARG_CALLEE_COPIES */
5071 /* In any case, record the parm's desired stack location
5072 in case we later discover it must live in the stack.
5074 If it is a COMPLEX value, store the stack location for both
5077 if (GET_CODE (parmreg) == CONCAT)
5078 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
5080 regno = REGNO (parmreg);
5082 if (regno >= max_parm_reg)
5085 int old_max_parm_reg = max_parm_reg;
5087 /* It's slow to expand this one register at a time,
5088 but it's also rare and we need max_parm_reg to be
5089 precisely correct. */
5090 max_parm_reg = regno + 1;
5091 new = ggc_realloc (parm_reg_stack_loc,
5092 max_parm_reg * sizeof (rtx));
5093 memset (new + old_max_parm_reg, 0,
5094 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
5095 parm_reg_stack_loc = new;
5098 if (GET_CODE (parmreg) == CONCAT)
5100 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
5102 regnor = REGNO (gen_realpart (submode, parmreg));
5103 regnoi = REGNO (gen_imagpart (submode, parmreg));
5105 if (stack_parm != 0)
5107 parm_reg_stack_loc[regnor]
5108 = gen_realpart (submode, stack_parm);
5109 parm_reg_stack_loc[regnoi]
5110 = gen_imagpart (submode, stack_parm);
5114 parm_reg_stack_loc[regnor] = 0;
5115 parm_reg_stack_loc[regnoi] = 0;
5119 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
5121 /* Mark the register as eliminable if we did no conversion
5122 and it was copied from memory at a fixed offset,
5123 and the arg pointer was not copied to a pseudo-reg.
5124 If the arg pointer is a pseudo reg or the offset formed
5125 an invalid address, such memory-equivalences
5126 as we make here would screw up life analysis for it. */
5127 if (nominal_mode == passed_mode
5130 && GET_CODE (stack_parm) == MEM
5131 && locate.offset.var == 0
5132 && reg_mentioned_p (virtual_incoming_args_rtx,
5133 XEXP (stack_parm, 0)))
5135 rtx linsn = get_last_insn ();
5138 /* Mark complex types separately. */
5139 if (GET_CODE (parmreg) == CONCAT)
5140 /* Scan backwards for the set of the real and
5142 for (sinsn = linsn; sinsn != 0;
5143 sinsn = prev_nonnote_insn (sinsn))
5145 set = single_set (sinsn);
5147 && SET_DEST (set) == regno_reg_rtx [regnoi])
5149 = gen_rtx_EXPR_LIST (REG_EQUIV,
5150 parm_reg_stack_loc[regnoi],
5153 && SET_DEST (set) == regno_reg_rtx [regnor])
5155 = gen_rtx_EXPR_LIST (REG_EQUIV,
5156 parm_reg_stack_loc[regnor],
5159 else if ((set = single_set (linsn)) != 0
5160 && SET_DEST (set) == parmreg)
5162 = gen_rtx_EXPR_LIST (REG_EQUIV,
5163 stack_parm, REG_NOTES (linsn));
5166 /* For pointer data type, suggest pointer register. */
5167 if (POINTER_TYPE_P (TREE_TYPE (parm)))
5168 mark_reg_pointer (parmreg,
5169 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
5171 /* If something wants our address, try to use ADDRESSOF. */
5172 if (TREE_ADDRESSABLE (parm))
5174 /* If we end up putting something into the stack,
5175 fixup_var_refs_insns will need to make a pass over
5176 all the instructions. It looks through the pending
5177 sequences -- but it can't see the ones in the
5178 CONVERSION_INSNS, if they're not on the sequence
5179 stack. So, we go back to that sequence, just so that
5180 the fixups will happen. */
5181 push_to_sequence (conversion_insns);
5182 put_var_into_stack (parm, /*rescan=*/true);
5183 conversion_insns = get_insns ();
5189 /* Value must be stored in the stack slot STACK_PARM
5190 during function execution. */
5192 if (promoted_mode != nominal_mode)
5194 /* Conversion is required. */
5195 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
5197 emit_move_insn (tempreg, validize_mem (entry_parm));
5199 push_to_sequence (conversion_insns);
5200 entry_parm = convert_to_mode (nominal_mode, tempreg,
5201 TYPE_UNSIGNED (TREE_TYPE (parm)));
5203 /* ??? This may need a big-endian conversion on sparc64. */
5204 stack_parm = adjust_address (stack_parm, nominal_mode, 0);
5206 conversion_insns = get_insns ();
5211 if (entry_parm != stack_parm)
5213 if (stack_parm == 0)
5216 = assign_stack_local (GET_MODE (entry_parm),
5217 GET_MODE_SIZE (GET_MODE (entry_parm)),
5219 set_mem_attributes (stack_parm, parm, 1);
5222 if (promoted_mode != nominal_mode)
5224 push_to_sequence (conversion_insns);
5225 emit_move_insn (validize_mem (stack_parm),
5226 validize_mem (entry_parm));
5227 conversion_insns = get_insns ();
5231 emit_move_insn (validize_mem (stack_parm),
5232 validize_mem (entry_parm));
5235 SET_DECL_RTL (parm, stack_parm);
5239 if (targetm.calls.split_complex_arg && fnargs != orig_fnargs)
5241 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm))
5243 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE
5244 && targetm.calls.split_complex_arg (TREE_TYPE (parm)))
5246 rtx tmp, real, imag;
5247 enum machine_mode inner = GET_MODE_INNER (DECL_MODE (parm));
5249 real = DECL_RTL (fnargs);
5250 imag = DECL_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_RTL (parm, tmp);
5259 real = DECL_INCOMING_RTL (fnargs);
5260 imag = DECL_INCOMING_RTL (TREE_CHAIN (fnargs));
5261 if (inner != GET_MODE (real))
5263 real = gen_lowpart_SUBREG (inner, real);
5264 imag = gen_lowpart_SUBREG (inner, imag);
5266 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
5267 set_decl_incoming_rtl (parm, tmp);
5268 fnargs = TREE_CHAIN (fnargs);
5272 SET_DECL_RTL (parm, DECL_RTL (fnargs));
5273 set_decl_incoming_rtl (parm, DECL_INCOMING_RTL (fnargs));
5275 /* Set MEM_EXPR to the original decl, i.e. to PARM,
5276 instead of the copy of decl, i.e. FNARGS. */
5277 if (DECL_INCOMING_RTL (parm)
5278 && GET_CODE (DECL_INCOMING_RTL (parm)) == MEM)
5279 set_mem_expr (DECL_INCOMING_RTL (parm), parm);
5281 fnargs = TREE_CHAIN (fnargs);
5285 /* Output all parameter conversion instructions (possibly including calls)
5286 now that all parameters have been copied out of hard registers. */
5287 emit_insn (conversion_insns);
5289 /* If we are receiving a struct value address as the first argument, set up
5290 the RTL for the function result. As this might require code to convert
5291 the transmitted address to Pmode, we do this here to ensure that possible
5292 preliminary conversions of the address have been emitted already. */
5293 if (function_result_decl)
5295 tree result = DECL_RESULT (fndecl);
5296 rtx addr = DECL_RTL (function_result_decl);
5299 addr = convert_memory_address (Pmode, addr);
5300 x = gen_rtx_MEM (DECL_MODE (result), addr);
5301 set_mem_attributes (x, result, 1);
5302 SET_DECL_RTL (result, x);
5305 last_parm_insn = get_last_insn ();
5307 /* We have aligned all the args, so add space for the pretend args. */
5308 stack_args_size.constant += extra_pretend_bytes;
5309 current_function_args_size = stack_args_size.constant;
5311 /* Adjust function incoming argument size for alignment and
5314 #ifdef REG_PARM_STACK_SPACE
5315 current_function_args_size = MAX (current_function_args_size,
5316 REG_PARM_STACK_SPACE (fndecl));
5319 current_function_args_size
5320 = ((current_function_args_size + STACK_BYTES - 1)
5321 / STACK_BYTES) * STACK_BYTES;
5323 #ifdef ARGS_GROW_DOWNWARD
5324 current_function_arg_offset_rtx
5325 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
5326 : expand_expr (size_diffop (stack_args_size.var,
5327 size_int (-stack_args_size.constant)),
5328 NULL_RTX, VOIDmode, 0));
5330 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
5333 /* See how many bytes, if any, of its args a function should try to pop
5336 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
5337 current_function_args_size);
5339 /* For stdarg.h function, save info about
5340 regs and stack space used by the named args. */
5342 current_function_args_info = args_so_far;
5344 /* Set the rtx used for the function return value. Put this in its
5345 own variable so any optimizers that need this information don't have
5346 to include tree.h. Do this here so it gets done when an inlined
5347 function gets output. */
5349 current_function_return_rtx
5350 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
5351 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
5353 /* If scalar return value was computed in a pseudo-reg, or was a named
5354 return value that got dumped to the stack, copy that to the hard
5356 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
5358 tree decl_result = DECL_RESULT (fndecl);
5359 rtx decl_rtl = DECL_RTL (decl_result);
5361 if (REG_P (decl_rtl)
5362 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5363 : DECL_REGISTER (decl_result))
5367 #ifdef FUNCTION_OUTGOING_VALUE
5368 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
5371 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
5374 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
5375 /* The delay slot scheduler assumes that current_function_return_rtx
5376 holds the hard register containing the return value, not a
5377 temporary pseudo. */
5378 current_function_return_rtx = real_decl_rtl;
5383 /* If ARGS contains entries with complex types, split the entry into two
5384 entries of the component type. Return a new list of substitutions are
5385 needed, else the old list. */
5388 split_complex_args (tree args)
5392 /* Before allocating memory, check for the common case of no complex. */
5393 for (p = args; p; p = TREE_CHAIN (p))
5395 tree type = TREE_TYPE (p);
5396 if (TREE_CODE (type) == COMPLEX_TYPE
5397 && targetm.calls.split_complex_arg (type))
5403 args = copy_list (args);
5405 for (p = args; p; p = TREE_CHAIN (p))
5407 tree type = TREE_TYPE (p);
5408 if (TREE_CODE (type) == COMPLEX_TYPE
5409 && targetm.calls.split_complex_arg (type))
5412 tree subtype = TREE_TYPE (type);
5414 /* Rewrite the PARM_DECL's type with its component. */
5415 TREE_TYPE (p) = subtype;
5416 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
5417 DECL_MODE (p) = VOIDmode;
5418 DECL_SIZE (p) = NULL;
5419 DECL_SIZE_UNIT (p) = NULL;
5422 /* Build a second synthetic decl. */
5423 decl = build_decl (PARM_DECL, NULL_TREE, subtype);
5424 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
5425 layout_decl (decl, 0);
5427 /* Splice it in; skip the new decl. */
5428 TREE_CHAIN (decl) = TREE_CHAIN (p);
5429 TREE_CHAIN (p) = decl;
5437 /* Indicate whether REGNO is an incoming argument to the current function
5438 that was promoted to a wider mode. If so, return the RTX for the
5439 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5440 that REGNO is promoted from and whether the promotion was signed or
5444 promoted_input_arg (unsigned int regno, enum machine_mode *pmode, int *punsignedp)
5448 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
5449 arg = TREE_CHAIN (arg))
5450 if (REG_P (DECL_INCOMING_RTL (arg))
5451 && REGNO (DECL_INCOMING_RTL (arg)) == regno
5452 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
5454 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
5455 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (arg));
5457 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
5458 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
5459 && mode != DECL_MODE (arg))
5461 *pmode = DECL_MODE (arg);
5462 *punsignedp = unsignedp;
5463 return DECL_INCOMING_RTL (arg);
5471 /* Compute the size and offset from the start of the stacked arguments for a
5472 parm passed in mode PASSED_MODE and with type TYPE.
5474 INITIAL_OFFSET_PTR points to the current offset into the stacked
5477 The starting offset and size for this parm are returned in
5478 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
5479 nonzero, the offset is that of stack slot, which is returned in
5480 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
5481 padding required from the initial offset ptr to the stack slot.
5483 IN_REGS is nonzero if the argument will be passed in registers. It will
5484 never be set if REG_PARM_STACK_SPACE is not defined.
5486 FNDECL is the function in which the argument was defined.
5488 There are two types of rounding that are done. The first, controlled by
5489 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5490 list to be aligned to the specific boundary (in bits). This rounding
5491 affects the initial and starting offsets, but not the argument size.
5493 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5494 optionally rounds the size of the parm to PARM_BOUNDARY. The
5495 initial offset is not affected by this rounding, while the size always
5496 is and the starting offset may be. */
5498 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
5499 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
5500 callers pass in the total size of args so far as
5501 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
5504 locate_and_pad_parm (enum machine_mode passed_mode, tree type, int in_regs,
5505 int partial, tree fndecl ATTRIBUTE_UNUSED,
5506 struct args_size *initial_offset_ptr,
5507 struct locate_and_pad_arg_data *locate)
5510 enum direction where_pad;
5512 int reg_parm_stack_space = 0;
5513 int part_size_in_regs;
5515 #ifdef REG_PARM_STACK_SPACE
5516 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5518 /* If we have found a stack parm before we reach the end of the
5519 area reserved for registers, skip that area. */
5522 if (reg_parm_stack_space > 0)
5524 if (initial_offset_ptr->var)
5526 initial_offset_ptr->var
5527 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5528 ssize_int (reg_parm_stack_space));
5529 initial_offset_ptr->constant = 0;
5531 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5532 initial_offset_ptr->constant = reg_parm_stack_space;
5535 #endif /* REG_PARM_STACK_SPACE */
5537 part_size_in_regs = 0;
5538 if (reg_parm_stack_space == 0)
5539 part_size_in_regs = ((partial * UNITS_PER_WORD)
5540 / (PARM_BOUNDARY / BITS_PER_UNIT)
5541 * (PARM_BOUNDARY / BITS_PER_UNIT));
5544 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5545 where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5546 boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5547 locate->where_pad = where_pad;
5549 #ifdef ARGS_GROW_DOWNWARD
5550 locate->slot_offset.constant = -initial_offset_ptr->constant;
5551 if (initial_offset_ptr->var)
5552 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
5553 initial_offset_ptr->var);
5557 if (where_pad != none
5558 && (!host_integerp (sizetree, 1)
5559 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5560 s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
5561 SUB_PARM_SIZE (locate->slot_offset, s2);
5564 locate->slot_offset.constant += part_size_in_regs;
5567 #ifdef REG_PARM_STACK_SPACE
5568 || REG_PARM_STACK_SPACE (fndecl) > 0
5571 pad_to_arg_alignment (&locate->slot_offset, boundary,
5572 &locate->alignment_pad);
5574 locate->size.constant = (-initial_offset_ptr->constant
5575 - locate->slot_offset.constant);
5576 if (initial_offset_ptr->var)
5577 locate->size.var = size_binop (MINUS_EXPR,
5578 size_binop (MINUS_EXPR,
5580 initial_offset_ptr->var),
5581 locate->slot_offset.var);
5583 /* Pad_below needs the pre-rounded size to know how much to pad
5585 locate->offset = locate->slot_offset;
5586 if (where_pad == downward)
5587 pad_below (&locate->offset, passed_mode, sizetree);
5589 #else /* !ARGS_GROW_DOWNWARD */
5591 #ifdef REG_PARM_STACK_SPACE
5592 || REG_PARM_STACK_SPACE (fndecl) > 0
5595 pad_to_arg_alignment (initial_offset_ptr, boundary,
5596 &locate->alignment_pad);
5597 locate->slot_offset = *initial_offset_ptr;
5599 #ifdef PUSH_ROUNDING
5600 if (passed_mode != BLKmode)
5601 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5604 /* Pad_below needs the pre-rounded size to know how much to pad below
5605 so this must be done before rounding up. */
5606 locate->offset = locate->slot_offset;
5607 if (where_pad == downward)
5608 pad_below (&locate->offset, passed_mode, sizetree);
5610 if (where_pad != none
5611 && (!host_integerp (sizetree, 1)
5612 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5613 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5615 ADD_PARM_SIZE (locate->size, sizetree);
5617 locate->size.constant -= part_size_in_regs;
5618 #endif /* ARGS_GROW_DOWNWARD */
5621 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5622 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5625 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
5626 struct args_size *alignment_pad)
5628 tree save_var = NULL_TREE;
5629 HOST_WIDE_INT save_constant = 0;
5630 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5631 HOST_WIDE_INT sp_offset = STACK_POINTER_OFFSET;
5633 #ifdef SPARC_STACK_BOUNDARY_HACK
5634 /* The sparc port has a bug. It sometimes claims a STACK_BOUNDARY
5635 higher than the real alignment of %sp. However, when it does this,
5636 the alignment of %sp+STACK_POINTER_OFFSET will be STACK_BOUNDARY.
5637 This is a temporary hack while the sparc port is fixed. */
5638 if (SPARC_STACK_BOUNDARY_HACK)
5642 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5644 save_var = offset_ptr->var;
5645 save_constant = offset_ptr->constant;
5648 alignment_pad->var = NULL_TREE;
5649 alignment_pad->constant = 0;
5651 if (boundary > BITS_PER_UNIT)
5653 if (offset_ptr->var)
5655 tree sp_offset_tree = ssize_int (sp_offset);
5656 tree offset = size_binop (PLUS_EXPR,
5657 ARGS_SIZE_TREE (*offset_ptr),
5659 #ifdef ARGS_GROW_DOWNWARD
5660 tree rounded = round_down (offset, boundary / BITS_PER_UNIT);
5662 tree rounded = round_up (offset, boundary / BITS_PER_UNIT);
5665 offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
5666 /* ARGS_SIZE_TREE includes constant term. */
5667 offset_ptr->constant = 0;
5668 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5669 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5674 offset_ptr->constant = -sp_offset +
5675 #ifdef ARGS_GROW_DOWNWARD
5676 FLOOR_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
5678 CEIL_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
5680 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5681 alignment_pad->constant = offset_ptr->constant - save_constant;
5687 pad_below (struct args_size *offset_ptr, enum machine_mode passed_mode, tree sizetree)
5689 if (passed_mode != BLKmode)
5691 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5692 offset_ptr->constant
5693 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5694 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5695 - GET_MODE_SIZE (passed_mode));
5699 if (TREE_CODE (sizetree) != INTEGER_CST
5700 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5702 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5703 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5705 ADD_PARM_SIZE (*offset_ptr, s2);
5706 SUB_PARM_SIZE (*offset_ptr, sizetree);
5711 /* Walk the tree of blocks describing the binding levels within a function
5712 and warn about variables the might be killed by setjmp or vfork.
5713 This is done after calling flow_analysis and before global_alloc
5714 clobbers the pseudo-regs to hard regs. */
5717 setjmp_vars_warning (tree block)
5721 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5723 if (TREE_CODE (decl) == VAR_DECL
5724 && DECL_RTL_SET_P (decl)
5725 && REG_P (DECL_RTL (decl))
5726 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5727 warning ("%Jvariable '%D' might be clobbered by `longjmp' or `vfork'",
5731 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5732 setjmp_vars_warning (sub);
5735 /* Do the appropriate part of setjmp_vars_warning
5736 but for arguments instead of local variables. */
5739 setjmp_args_warning (void)
5742 for (decl = DECL_ARGUMENTS (current_function_decl);
5743 decl; decl = TREE_CHAIN (decl))
5744 if (DECL_RTL (decl) != 0
5745 && REG_P (DECL_RTL (decl))
5746 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5747 warning ("%Jargument '%D' might be clobbered by `longjmp' or `vfork'",
5751 /* If this function call setjmp, put all vars into the stack
5752 unless they were declared `register'. */
5755 setjmp_protect (tree block)
5758 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5759 if ((TREE_CODE (decl) == VAR_DECL
5760 || TREE_CODE (decl) == PARM_DECL)
5761 && DECL_RTL (decl) != 0
5762 && (REG_P (DECL_RTL (decl))
5763 || (GET_CODE (DECL_RTL (decl)) == MEM
5764 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5765 /* If this variable came from an inline function, it must be
5766 that its life doesn't overlap the setjmp. If there was a
5767 setjmp in the function, it would already be in memory. We
5768 must exclude such variable because their DECL_RTL might be
5769 set to strange things such as virtual_stack_vars_rtx. */
5770 && ! DECL_FROM_INLINE (decl)
5772 #ifdef NON_SAVING_SETJMP
5773 /* If longjmp doesn't restore the registers,
5774 don't put anything in them. */
5778 ! DECL_REGISTER (decl)))
5779 put_var_into_stack (decl, /*rescan=*/true);
5780 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5781 setjmp_protect (sub);
5784 /* Like the previous function, but for args instead of local variables. */
5787 setjmp_protect_args (void)
5790 for (decl = DECL_ARGUMENTS (current_function_decl);
5791 decl; decl = TREE_CHAIN (decl))
5792 if ((TREE_CODE (decl) == VAR_DECL
5793 || TREE_CODE (decl) == PARM_DECL)
5794 && DECL_RTL (decl) != 0
5795 && (REG_P (DECL_RTL (decl))
5796 || (GET_CODE (DECL_RTL (decl)) == MEM
5797 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5799 /* If longjmp doesn't restore the registers,
5800 don't put anything in them. */
5801 #ifdef NON_SAVING_SETJMP
5805 ! DECL_REGISTER (decl)))
5806 put_var_into_stack (decl, /*rescan=*/true);
5809 /* Convert a stack slot address ADDR for variable VAR
5810 (from a containing function)
5811 into an address valid in this function (using a static chain). */
5814 fix_lexical_addr (rtx addr, tree var)
5817 HOST_WIDE_INT displacement;
5818 tree context = decl_function_context (var);
5819 struct function *fp;
5822 /* If this is the present function, we need not do anything. */
5823 if (context == current_function_decl)
5826 fp = find_function_data (context);
5828 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5829 addr = XEXP (XEXP (addr, 0), 0);
5831 /* Decode given address as base reg plus displacement. */
5833 basereg = addr, displacement = 0;
5834 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5835 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5842 /* Use same offset, relative to appropriate static chain or argument
5844 return plus_constant (base, displacement);
5847 /* Put all this function's BLOCK nodes including those that are chained
5848 onto the first block into a vector, and return it.
5849 Also store in each NOTE for the beginning or end of a block
5850 the index of that block in the vector.
5851 The arguments are BLOCK, the chain of top-level blocks of the function,
5852 and INSNS, the insn chain of the function. */
5855 identify_blocks (void)
5858 tree *block_vector, *last_block_vector;
5860 tree block = DECL_INITIAL (current_function_decl);
5865 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5866 depth-first order. */
5867 block_vector = get_block_vector (block, &n_blocks);
5868 block_stack = xmalloc (n_blocks * sizeof (tree));
5870 last_block_vector = identify_blocks_1 (get_insns (),
5872 block_vector + n_blocks,
5875 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5876 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5877 if (0 && last_block_vector != block_vector + n_blocks)
5880 free (block_vector);
5884 /* Subroutine of identify_blocks. Do the block substitution on the
5885 insn chain beginning with INSNS.
5887 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5888 BLOCK_VECTOR is incremented for each block seen. */
5891 identify_blocks_1 (rtx insns, tree *block_vector, tree *end_block_vector,
5892 tree *orig_block_stack)
5895 tree *block_stack = orig_block_stack;
5897 for (insn = insns; insn; insn = NEXT_INSN (insn))
5899 if (GET_CODE (insn) == NOTE)
5901 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5905 /* If there are more block notes than BLOCKs, something
5907 if (block_vector == end_block_vector)
5910 b = *block_vector++;
5911 NOTE_BLOCK (insn) = b;
5914 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5916 /* If there are more NOTE_INSN_BLOCK_ENDs than
5917 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
5918 if (block_stack == orig_block_stack)
5921 NOTE_BLOCK (insn) = *--block_stack;
5926 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
5927 something is badly wrong. */
5928 if (block_stack != orig_block_stack)
5931 return block_vector;
5934 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
5935 and create duplicate blocks. */
5936 /* ??? Need an option to either create block fragments or to create
5937 abstract origin duplicates of a source block. It really depends
5938 on what optimization has been performed. */
5941 reorder_blocks (void)
5943 tree block = DECL_INITIAL (current_function_decl);
5944 varray_type block_stack;
5946 if (block == NULL_TREE)
5949 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
5951 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
5952 clear_block_marks (block);
5954 /* Prune the old trees away, so that they don't get in the way. */
5955 BLOCK_SUBBLOCKS (block) = NULL_TREE;
5956 BLOCK_CHAIN (block) = NULL_TREE;
5958 /* Recreate the block tree from the note nesting. */
5959 reorder_blocks_1 (get_insns (), block, &block_stack);
5960 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
5962 /* Remove deleted blocks from the block fragment chains. */
5963 reorder_fix_fragments (block);
5966 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
5969 clear_block_marks (tree block)
5973 TREE_ASM_WRITTEN (block) = 0;
5974 clear_block_marks (BLOCK_SUBBLOCKS (block));
5975 block = BLOCK_CHAIN (block);
5980 reorder_blocks_1 (rtx insns, tree current_block, varray_type *p_block_stack)
5984 for (insn = insns; insn; insn = NEXT_INSN (insn))
5986 if (GET_CODE (insn) == NOTE)
5988 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5990 tree block = NOTE_BLOCK (insn);
5992 /* If we have seen this block before, that means it now
5993 spans multiple address regions. Create a new fragment. */
5994 if (TREE_ASM_WRITTEN (block))
5996 tree new_block = copy_node (block);
5999 origin = (BLOCK_FRAGMENT_ORIGIN (block)
6000 ? BLOCK_FRAGMENT_ORIGIN (block)
6002 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
6003 BLOCK_FRAGMENT_CHAIN (new_block)
6004 = BLOCK_FRAGMENT_CHAIN (origin);
6005 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
6007 NOTE_BLOCK (insn) = new_block;
6011 BLOCK_SUBBLOCKS (block) = 0;
6012 TREE_ASM_WRITTEN (block) = 1;
6013 /* When there's only one block for the entire function,
6014 current_block == block and we mustn't do this, it
6015 will cause infinite recursion. */
6016 if (block != current_block)
6018 BLOCK_SUPERCONTEXT (block) = current_block;
6019 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
6020 BLOCK_SUBBLOCKS (current_block) = block;
6021 current_block = block;
6023 VARRAY_PUSH_TREE (*p_block_stack, block);
6025 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
6027 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
6028 VARRAY_POP (*p_block_stack);
6029 BLOCK_SUBBLOCKS (current_block)
6030 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
6031 current_block = BLOCK_SUPERCONTEXT (current_block);
6037 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
6038 appears in the block tree, select one of the fragments to become
6039 the new origin block. */
6042 reorder_fix_fragments (tree block)
6046 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
6047 tree new_origin = NULL_TREE;
6051 if (! TREE_ASM_WRITTEN (dup_origin))
6053 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
6055 /* Find the first of the remaining fragments. There must
6056 be at least one -- the current block. */
6057 while (! TREE_ASM_WRITTEN (new_origin))
6058 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
6059 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
6062 else if (! dup_origin)
6065 /* Re-root the rest of the fragments to the new origin. In the
6066 case that DUP_ORIGIN was null, that means BLOCK was the origin
6067 of a chain of fragments and we want to remove those fragments
6068 that didn't make it to the output. */
6071 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
6076 if (TREE_ASM_WRITTEN (chain))
6078 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
6080 pp = &BLOCK_FRAGMENT_CHAIN (chain);
6082 chain = BLOCK_FRAGMENT_CHAIN (chain);
6087 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
6088 block = BLOCK_CHAIN (block);
6092 /* Reverse the order of elements in the chain T of blocks,
6093 and return the new head of the chain (old last element). */
6096 blocks_nreverse (tree t)
6098 tree prev = 0, decl, next;
6099 for (decl = t; decl; decl = next)
6101 next = BLOCK_CHAIN (decl);
6102 BLOCK_CHAIN (decl) = prev;
6108 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
6109 non-NULL, list them all into VECTOR, in a depth-first preorder
6110 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
6114 all_blocks (tree block, tree *vector)
6120 TREE_ASM_WRITTEN (block) = 0;
6122 /* Record this block. */
6124 vector[n_blocks] = block;
6128 /* Record the subblocks, and their subblocks... */
6129 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
6130 vector ? vector + n_blocks : 0);
6131 block = BLOCK_CHAIN (block);
6137 /* Return a vector containing all the blocks rooted at BLOCK. The
6138 number of elements in the vector is stored in N_BLOCKS_P. The
6139 vector is dynamically allocated; it is the caller's responsibility
6140 to call `free' on the pointer returned. */
6143 get_block_vector (tree block, int *n_blocks_p)
6147 *n_blocks_p = all_blocks (block, NULL);
6148 block_vector = xmalloc (*n_blocks_p * sizeof (tree));
6149 all_blocks (block, block_vector);
6151 return block_vector;
6154 static GTY(()) int next_block_index = 2;
6156 /* Set BLOCK_NUMBER for all the blocks in FN. */
6159 number_blocks (tree fn)
6165 /* For SDB and XCOFF debugging output, we start numbering the blocks
6166 from 1 within each function, rather than keeping a running
6168 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6169 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
6170 next_block_index = 1;
6173 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
6175 /* The top-level BLOCK isn't numbered at all. */
6176 for (i = 1; i < n_blocks; ++i)
6177 /* We number the blocks from two. */
6178 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
6180 free (block_vector);
6185 /* If VAR is present in a subblock of BLOCK, return the subblock. */
6188 debug_find_var_in_block_tree (tree var, tree block)
6192 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
6196 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
6198 tree ret = debug_find_var_in_block_tree (var, t);
6206 /* Allocate a function structure for FNDECL and set its contents
6210 allocate_struct_function (tree fndecl)
6213 tree fntype = fndecl ? TREE_TYPE (fndecl) : NULL_TREE;
6215 cfun = ggc_alloc_cleared (sizeof (struct function));
6217 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
6219 cfun->stack_alignment_needed = STACK_BOUNDARY;
6220 cfun->preferred_stack_boundary = STACK_BOUNDARY;
6222 current_function_funcdef_no = funcdef_no++;
6224 cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL;
6226 init_stmt_for_function ();
6227 init_eh_for_function ();
6229 lang_hooks.function.init (cfun);
6230 if (init_machine_status)
6231 cfun->machine = (*init_machine_status) ();
6236 DECL_STRUCT_FUNCTION (fndecl) = cfun;
6237 cfun->decl = fndecl;
6239 result = DECL_RESULT (fndecl);
6240 if (aggregate_value_p (result, fndecl))
6242 #ifdef PCC_STATIC_STRUCT_RETURN
6243 current_function_returns_pcc_struct = 1;
6245 current_function_returns_struct = 1;
6248 current_function_returns_pointer = POINTER_TYPE_P (TREE_TYPE (result));
6250 current_function_stdarg
6252 && TYPE_ARG_TYPES (fntype) != 0
6253 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
6254 != void_type_node));
6257 /* Reset cfun, and other non-struct-function variables to defaults as
6258 appropriate for emitting rtl at the start of a function. */
6261 prepare_function_start (tree fndecl)
6263 if (fndecl && DECL_STRUCT_FUNCTION (fndecl))
6264 cfun = DECL_STRUCT_FUNCTION (fndecl);
6266 allocate_struct_function (fndecl);
6268 init_varasm_status (cfun);
6271 cse_not_expected = ! optimize;
6273 /* Caller save not needed yet. */
6274 caller_save_needed = 0;
6276 /* We haven't done register allocation yet. */
6279 /* Indicate that we need to distinguish between the return value of the
6280 present function and the return value of a function being called. */
6281 rtx_equal_function_value_matters = 1;
6283 /* Indicate that we have not instantiated virtual registers yet. */
6284 virtuals_instantiated = 0;
6286 /* Indicate that we want CONCATs now. */
6287 generating_concat_p = 1;
6289 /* Indicate we have no need of a frame pointer yet. */
6290 frame_pointer_needed = 0;
6293 /* Initialize the rtl expansion mechanism so that we can do simple things
6294 like generate sequences. This is used to provide a context during global
6295 initialization of some passes. */
6297 init_dummy_function_start (void)
6299 prepare_function_start (NULL);
6302 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6303 and initialize static variables for generating RTL for the statements
6307 init_function_start (tree subr)
6309 prepare_function_start (subr);
6311 /* Within function body, compute a type's size as soon it is laid out. */
6312 immediate_size_expand++;
6314 /* Prevent ever trying to delete the first instruction of a
6315 function. Also tell final how to output a linenum before the
6316 function prologue. Note linenums could be missing, e.g. when
6317 compiling a Java .class file. */
6318 if (DECL_SOURCE_LINE (subr))
6319 emit_line_note (DECL_SOURCE_LOCATION (subr));
6321 /* Make sure first insn is a note even if we don't want linenums.
6322 This makes sure the first insn will never be deleted.
6323 Also, final expects a note to appear there. */
6324 emit_note (NOTE_INSN_DELETED);
6326 /* Warn if this value is an aggregate type,
6327 regardless of which calling convention we are using for it. */
6328 if (warn_aggregate_return
6329 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6330 warning ("function returns an aggregate");
6333 /* Make sure all values used by the optimization passes have sane
6336 init_function_for_compilation (void)
6340 /* No prologue/epilogue insns yet. */
6341 VARRAY_GROW (prologue, 0);
6342 VARRAY_GROW (epilogue, 0);
6343 VARRAY_GROW (sibcall_epilogue, 0);
6346 /* Expand a call to __main at the beginning of a possible main function. */
6348 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6349 #undef HAS_INIT_SECTION
6350 #define HAS_INIT_SECTION
6354 expand_main_function (void)
6356 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
6357 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
6359 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
6363 /* Forcibly align the stack. */
6364 #ifdef STACK_GROWS_DOWNWARD
6365 tmp = expand_simple_binop (Pmode, AND, stack_pointer_rtx, GEN_INT(-align),
6366 stack_pointer_rtx, 1, OPTAB_WIDEN);
6368 tmp = expand_simple_binop (Pmode, PLUS, stack_pointer_rtx,
6369 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
6370 tmp = expand_simple_binop (Pmode, AND, tmp, GEN_INT (-align),
6371 stack_pointer_rtx, 1, OPTAB_WIDEN);
6373 if (tmp != stack_pointer_rtx)
6374 emit_move_insn (stack_pointer_rtx, tmp);
6376 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
6377 tmp = force_reg (Pmode, const0_rtx);
6378 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
6382 for (tmp = get_last_insn (); tmp; tmp = PREV_INSN (tmp))
6383 if (NOTE_P (tmp) && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_FUNCTION_BEG)
6386 emit_insn_before (seq, tmp);
6392 #ifndef HAS_INIT_SECTION
6393 emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0);
6397 /* The PENDING_SIZES represent the sizes of variable-sized types.
6398 Create RTL for the various sizes now (using temporary variables),
6399 so that we can refer to the sizes from the RTL we are generating
6400 for the current function. The PENDING_SIZES are a TREE_LIST. The
6401 TREE_VALUE of each node is a SAVE_EXPR. */
6404 expand_pending_sizes (tree pending_sizes)
6408 /* Evaluate now the sizes of any types declared among the arguments. */
6409 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
6411 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode, 0);
6412 /* Flush the queue in case this parameter declaration has
6418 /* Start the RTL for a new function, and set variables used for
6420 SUBR is the FUNCTION_DECL node.
6421 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6422 the function's parameters, which must be run at any return statement. */
6425 expand_function_start (tree subr, int parms_have_cleanups)
6427 /* Make sure volatile mem refs aren't considered
6428 valid operands of arithmetic insns. */
6429 init_recog_no_volatile ();
6431 current_function_profile
6433 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6435 current_function_limit_stack
6436 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6438 /* If the parameters of this function need cleaning up, get a label
6439 for the beginning of the code which executes those cleanups. This must
6440 be done before doing anything with return_label. */
6441 if (parms_have_cleanups)
6442 cleanup_label = gen_label_rtx ();
6446 /* Make the label for return statements to jump to. Do not special
6447 case machines with special return instructions -- they will be
6448 handled later during jump, ifcvt, or epilogue creation. */
6449 return_label = gen_label_rtx ();
6451 /* Initialize rtx used to return the value. */
6452 /* Do this before assign_parms so that we copy the struct value address
6453 before any library calls that assign parms might generate. */
6455 /* Decide whether to return the value in memory or in a register. */
6456 if (aggregate_value_p (DECL_RESULT (subr), subr))
6458 /* Returning something that won't go in a register. */
6459 rtx value_address = 0;
6461 #ifdef PCC_STATIC_STRUCT_RETURN
6462 if (current_function_returns_pcc_struct)
6464 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6465 value_address = assemble_static_space (size);
6470 rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 1);
6471 /* Expect to be passed the address of a place to store the value.
6472 If it is passed as an argument, assign_parms will take care of
6476 value_address = gen_reg_rtx (Pmode);
6477 emit_move_insn (value_address, sv);
6482 rtx x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
6483 set_mem_attributes (x, DECL_RESULT (subr), 1);
6484 SET_DECL_RTL (DECL_RESULT (subr), x);
6487 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6488 /* If return mode is void, this decl rtl should not be used. */
6489 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
6492 /* Compute the return values into a pseudo reg, which we will copy
6493 into the true return register after the cleanups are done. */
6495 /* In order to figure out what mode to use for the pseudo, we
6496 figure out what the mode of the eventual return register will
6497 actually be, and use that. */
6499 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
6502 /* Structures that are returned in registers are not aggregate_value_p,
6503 so we may see a PARALLEL or a REG. */
6504 if (REG_P (hard_reg))
6505 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg)));
6506 else if (GET_CODE (hard_reg) == PARALLEL)
6507 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
6511 /* Set DECL_REGISTER flag so that expand_function_end will copy the
6512 result to the real return register(s). */
6513 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6516 /* Initialize rtx for parameters and local variables.
6517 In some cases this requires emitting insns. */
6518 assign_parms (subr);
6520 /* If function gets a static chain arg, store it. */
6521 if (cfun->static_chain_decl)
6523 tree parm = cfun->static_chain_decl;
6524 rtx local = gen_reg_rtx (Pmode);
6526 set_decl_incoming_rtl (parm, static_chain_incoming_rtx);
6527 SET_DECL_RTL (parm, local);
6528 maybe_set_unchanging (local, parm);
6529 mark_reg_pointer (local, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
6531 emit_move_insn (local, static_chain_incoming_rtx);
6534 /* If the function receives a non-local goto, then store the
6535 bits we need to restore the frame pointer. */
6536 if (cfun->nonlocal_goto_save_area)
6541 /* ??? We need to do this save early. Unfortunately here is
6542 before the frame variable gets declared. Help out... */
6543 expand_var (TREE_OPERAND (cfun->nonlocal_goto_save_area, 0));
6545 t_save = build (ARRAY_REF, ptr_type_node, cfun->nonlocal_goto_save_area,
6546 integer_zero_node, NULL_TREE, NULL_TREE);
6547 r_save = expand_expr (t_save, NULL_RTX, VOIDmode, EXPAND_WRITE);
6549 emit_move_insn (r_save, virtual_stack_vars_rtx);
6550 update_nonlocal_goto_save_area ();
6553 /* The following was moved from init_function_start.
6554 The move is supposed to make sdb output more accurate. */
6555 /* Indicate the beginning of the function body,
6556 as opposed to parm setup. */
6557 emit_note (NOTE_INSN_FUNCTION_BEG);
6559 if (GET_CODE (get_last_insn ()) != NOTE)
6560 emit_note (NOTE_INSN_DELETED);
6561 parm_birth_insn = get_last_insn ();
6563 if (current_function_profile)
6566 PROFILE_HOOK (current_function_funcdef_no);
6570 /* After the display initializations is where the tail-recursion label
6571 should go, if we end up needing one. Ensure we have a NOTE here
6572 since some things (like trampolines) get placed before this. */
6573 tail_recursion_reentry = emit_note (NOTE_INSN_DELETED);
6575 /* Evaluate now the sizes of any types declared among the arguments. */
6576 expand_pending_sizes (nreverse (get_pending_sizes ()));
6578 /* Make sure there is a line number after the function entry setup code. */
6579 force_next_line_note ();
6582 /* Undo the effects of init_dummy_function_start. */
6584 expand_dummy_function_end (void)
6586 /* End any sequences that failed to be closed due to syntax errors. */
6587 while (in_sequence_p ())
6590 /* Outside function body, can't compute type's actual size
6591 until next function's body starts. */
6593 free_after_parsing (cfun);
6594 free_after_compilation (cfun);
6598 /* Call DOIT for each hard register used as a return value from
6599 the current function. */
6602 diddle_return_value (void (*doit) (rtx, void *), void *arg)
6604 rtx outgoing = current_function_return_rtx;
6609 if (REG_P (outgoing))
6610 (*doit) (outgoing, arg);
6611 else if (GET_CODE (outgoing) == PARALLEL)
6615 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6617 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6619 if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER)
6626 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
6628 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6632 clobber_return_register (void)
6634 diddle_return_value (do_clobber_return_reg, NULL);
6636 /* In case we do use pseudo to return value, clobber it too. */
6637 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6639 tree decl_result = DECL_RESULT (current_function_decl);
6640 rtx decl_rtl = DECL_RTL (decl_result);
6641 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
6643 do_clobber_return_reg (decl_rtl, NULL);
6649 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
6651 emit_insn (gen_rtx_USE (VOIDmode, reg));
6655 use_return_register (void)
6657 diddle_return_value (do_use_return_reg, NULL);
6660 /* Possibly warn about unused parameters. */
6662 do_warn_unused_parameter (tree fn)
6666 for (decl = DECL_ARGUMENTS (fn);
6667 decl; decl = TREE_CHAIN (decl))
6668 if (!TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6669 && DECL_NAME (decl) && !DECL_ARTIFICIAL (decl))
6670 warning ("%Junused parameter '%D'", decl, decl);
6673 static GTY(()) rtx initial_trampoline;
6675 /* Generate RTL for the end of the current function. */
6678 expand_function_end (void)
6682 finish_expr_for_function ();
6684 /* If arg_pointer_save_area was referenced only from a nested
6685 function, we will not have initialized it yet. Do that now. */
6686 if (arg_pointer_save_area && ! cfun->arg_pointer_save_area_init)
6687 get_arg_pointer_save_area (cfun);
6689 #ifdef NON_SAVING_SETJMP
6690 /* Don't put any variables in registers if we call setjmp
6691 on a machine that fails to restore the registers. */
6692 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6694 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6695 setjmp_protect (DECL_INITIAL (current_function_decl));
6697 setjmp_protect_args ();
6701 /* If we are doing stack checking and this function makes calls,
6702 do a stack probe at the start of the function to ensure we have enough
6703 space for another stack frame. */
6704 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6708 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6709 if (GET_CODE (insn) == CALL_INSN)
6712 probe_stack_range (STACK_CHECK_PROTECT,
6713 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6716 emit_insn_before (seq, tail_recursion_reentry);
6721 /* Possibly warn about unused parameters.
6722 When frontend does unit-at-a-time, the warning is already
6723 issued at finalization time. */
6724 if (warn_unused_parameter
6725 && !lang_hooks.callgraph.expand_function)
6726 do_warn_unused_parameter (current_function_decl);
6728 /* End any sequences that failed to be closed due to syntax errors. */
6729 while (in_sequence_p ())
6732 /* Outside function body, can't compute type's actual size
6733 until next function's body starts. */
6734 immediate_size_expand--;
6736 clear_pending_stack_adjust ();
6737 do_pending_stack_adjust ();
6739 /* @@@ This is a kludge. We want to ensure that instructions that
6740 may trap are not moved into the epilogue by scheduling, because
6741 we don't always emit unwind information for the epilogue.
6742 However, not all machine descriptions define a blockage insn, so
6743 emit an ASM_INPUT to act as one. */
6744 if (flag_non_call_exceptions)
6745 emit_insn (gen_rtx_ASM_INPUT (VOIDmode, ""));
6747 /* Mark the end of the function body.
6748 If control reaches this insn, the function can drop through
6749 without returning a value. */
6750 emit_note (NOTE_INSN_FUNCTION_END);
6752 /* Must mark the last line number note in the function, so that the test
6753 coverage code can avoid counting the last line twice. This just tells
6754 the code to ignore the immediately following line note, since there
6755 already exists a copy of this note somewhere above. This line number
6756 note is still needed for debugging though, so we can't delete it. */
6757 if (flag_test_coverage)
6758 emit_note (NOTE_INSN_REPEATED_LINE_NUMBER);
6760 /* Output a linenumber for the end of the function.
6761 SDB depends on this. */
6762 force_next_line_note ();
6763 emit_line_note (input_location);
6765 /* Before the return label (if any), clobber the return
6766 registers so that they are not propagated live to the rest of
6767 the function. This can only happen with functions that drop
6768 through; if there had been a return statement, there would
6769 have either been a return rtx, or a jump to the return label.
6771 We delay actual code generation after the current_function_value_rtx
6773 clobber_after = get_last_insn ();
6775 /* Output the label for the actual return from the function,
6776 if one is expected. This happens either because a function epilogue
6777 is used instead of a return instruction, or because a return was done
6778 with a goto in order to run local cleanups, or because of pcc-style
6779 structure returning. */
6781 emit_label (return_label);
6783 /* Let except.c know where it should emit the call to unregister
6784 the function context for sjlj exceptions. */
6785 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
6786 sjlj_emit_function_exit_after (get_last_insn ());
6788 /* If we had calls to alloca, and this machine needs
6789 an accurate stack pointer to exit the function,
6790 insert some code to save and restore the stack pointer. */
6791 if (! EXIT_IGNORE_STACK
6792 && current_function_calls_alloca)
6796 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
6797 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
6800 /* If scalar return value was computed in a pseudo-reg, or was a named
6801 return value that got dumped to the stack, copy that to the hard
6803 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6805 tree decl_result = DECL_RESULT (current_function_decl);
6806 rtx decl_rtl = DECL_RTL (decl_result);
6808 if (REG_P (decl_rtl)
6809 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
6810 : DECL_REGISTER (decl_result))
6812 rtx real_decl_rtl = current_function_return_rtx;
6814 /* This should be set in assign_parms. */
6815 if (! REG_FUNCTION_VALUE_P (real_decl_rtl))
6818 /* If this is a BLKmode structure being returned in registers,
6819 then use the mode computed in expand_return. Note that if
6820 decl_rtl is memory, then its mode may have been changed,
6821 but that current_function_return_rtx has not. */
6822 if (GET_MODE (real_decl_rtl) == BLKmode)
6823 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
6825 /* If a named return value dumped decl_return to memory, then
6826 we may need to re-do the PROMOTE_MODE signed/unsigned
6828 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
6830 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (decl_result));
6832 if (targetm.calls.promote_function_return (TREE_TYPE (current_function_decl)))
6833 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
6836 convert_move (real_decl_rtl, decl_rtl, unsignedp);
6838 else if (GET_CODE (real_decl_rtl) == PARALLEL)
6840 /* If expand_function_start has created a PARALLEL for decl_rtl,
6841 move the result to the real return registers. Otherwise, do
6842 a group load from decl_rtl for a named return. */
6843 if (GET_CODE (decl_rtl) == PARALLEL)
6844 emit_group_move (real_decl_rtl, decl_rtl);
6846 emit_group_load (real_decl_rtl, decl_rtl,
6847 TREE_TYPE (decl_result),
6848 int_size_in_bytes (TREE_TYPE (decl_result)));
6851 emit_move_insn (real_decl_rtl, decl_rtl);
6855 /* If returning a structure, arrange to return the address of the value
6856 in a place where debuggers expect to find it.
6858 If returning a structure PCC style,
6859 the caller also depends on this value.
6860 And current_function_returns_pcc_struct is not necessarily set. */
6861 if (current_function_returns_struct
6862 || current_function_returns_pcc_struct)
6865 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
6866 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
6867 #ifdef FUNCTION_OUTGOING_VALUE
6869 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
6870 current_function_decl);
6873 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
6876 /* Mark this as a function return value so integrate will delete the
6877 assignment and USE below when inlining this function. */
6878 REG_FUNCTION_VALUE_P (outgoing) = 1;
6880 /* The address may be ptr_mode and OUTGOING may be Pmode. */
6881 value_address = convert_memory_address (GET_MODE (outgoing),
6884 emit_move_insn (outgoing, value_address);
6886 /* Show return register used to hold result (in this case the address
6888 current_function_return_rtx = outgoing;
6891 /* If this is an implementation of throw, do what's necessary to
6892 communicate between __builtin_eh_return and the epilogue. */
6893 expand_eh_return ();
6895 /* Emit the actual code to clobber return register. */
6900 clobber_return_register ();
6904 after = emit_insn_after (seq, clobber_after);
6907 /* Output the label for the naked return from the function, if one is
6908 expected. This is currently used only by __builtin_return. */
6909 if (naked_return_label)
6910 emit_label (naked_return_label);
6912 /* ??? This should no longer be necessary since stupid is no longer with
6913 us, but there are some parts of the compiler (eg reload_combine, and
6914 sh mach_dep_reorg) that still try and compute their own lifetime info
6915 instead of using the general framework. */
6916 use_return_register ();
6918 /* Fix up any gotos that jumped out to the outermost
6919 binding level of the function.
6920 Must follow emitting RETURN_LABEL. */
6922 /* If you have any cleanups to do at this point,
6923 and they need to create temporary variables,
6924 then you will lose. */
6925 expand_fixups (get_insns ());
6929 get_arg_pointer_save_area (struct function *f)
6931 rtx ret = f->x_arg_pointer_save_area;
6935 ret = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, f);
6936 f->x_arg_pointer_save_area = ret;
6939 if (f == cfun && ! f->arg_pointer_save_area_init)
6943 /* Save the arg pointer at the beginning of the function. The
6944 generated stack slot may not be a valid memory address, so we
6945 have to check it and fix it if necessary. */
6947 emit_move_insn (validize_mem (ret), virtual_incoming_args_rtx);
6951 push_topmost_sequence ();
6952 emit_insn_after (seq, get_insns ());
6953 pop_topmost_sequence ();
6959 /* Extend a vector that records the INSN_UIDs of INSNS
6960 (a list of one or more insns). */
6963 record_insns (rtx insns, varray_type *vecp)
6970 while (tmp != NULL_RTX)
6973 tmp = NEXT_INSN (tmp);
6976 i = VARRAY_SIZE (*vecp);
6977 VARRAY_GROW (*vecp, i + len);
6979 while (tmp != NULL_RTX)
6981 VARRAY_INT (*vecp, i) = INSN_UID (tmp);
6983 tmp = NEXT_INSN (tmp);
6987 /* Set the locator of the insn chain starting at INSN to LOC. */
6989 set_insn_locators (rtx insn, int loc)
6991 while (insn != NULL_RTX)
6994 INSN_LOCATOR (insn) = loc;
6995 insn = NEXT_INSN (insn);
6999 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
7000 be running after reorg, SEQUENCE rtl is possible. */
7003 contains (rtx insn, varray_type vec)
7007 if (GET_CODE (insn) == INSN
7008 && GET_CODE (PATTERN (insn)) == SEQUENCE)
7011 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
7012 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7013 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
7019 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7020 if (INSN_UID (insn) == VARRAY_INT (vec, j))
7027 prologue_epilogue_contains (rtx insn)
7029 if (contains (insn, prologue))
7031 if (contains (insn, epilogue))
7037 sibcall_epilogue_contains (rtx insn)
7039 if (sibcall_epilogue)
7040 return contains (insn, sibcall_epilogue);
7045 /* Insert gen_return at the end of block BB. This also means updating
7046 block_for_insn appropriately. */
7049 emit_return_into_block (basic_block bb, rtx line_note)
7051 emit_jump_insn_after (gen_return (), BB_END (bb));
7053 emit_note_copy_after (line_note, PREV_INSN (BB_END (bb)));
7055 #endif /* HAVE_return */
7057 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
7059 /* These functions convert the epilogue into a variant that does not modify the
7060 stack pointer. This is used in cases where a function returns an object
7061 whose size is not known until it is computed. The called function leaves the
7062 object on the stack, leaves the stack depressed, and returns a pointer to
7065 What we need to do is track all modifications and references to the stack
7066 pointer, deleting the modifications and changing the references to point to
7067 the location the stack pointer would have pointed to had the modifications
7070 These functions need to be portable so we need to make as few assumptions
7071 about the epilogue as we can. However, the epilogue basically contains
7072 three things: instructions to reset the stack pointer, instructions to
7073 reload registers, possibly including the frame pointer, and an
7074 instruction to return to the caller.
7076 If we can't be sure of what a relevant epilogue insn is doing, we abort.
7077 We also make no attempt to validate the insns we make since if they are
7078 invalid, we probably can't do anything valid. The intent is that these
7079 routines get "smarter" as more and more machines start to use them and
7080 they try operating on different epilogues.
7082 We use the following structure to track what the part of the epilogue that
7083 we've already processed has done. We keep two copies of the SP equivalence,
7084 one for use during the insn we are processing and one for use in the next
7085 insn. The difference is because one part of a PARALLEL may adjust SP
7086 and the other may use it. */
7090 rtx sp_equiv_reg; /* REG that SP is set from, perhaps SP. */
7091 HOST_WIDE_INT sp_offset; /* Offset from SP_EQUIV_REG of present SP. */
7092 rtx new_sp_equiv_reg; /* REG to be used at end of insn. */
7093 HOST_WIDE_INT new_sp_offset; /* Offset to be used at end of insn. */
7094 rtx equiv_reg_src; /* If nonzero, the value that SP_EQUIV_REG
7095 should be set to once we no longer need
7097 rtx const_equiv[FIRST_PSEUDO_REGISTER]; /* Any known constant equivalences
7101 static void handle_epilogue_set (rtx, struct epi_info *);
7102 static void update_epilogue_consts (rtx, rtx, void *);
7103 static void emit_equiv_load (struct epi_info *);
7105 /* Modify INSN, a list of one or more insns that is part of the epilogue, to
7106 no modifications to the stack pointer. Return the new list of insns. */
7109 keep_stack_depressed (rtx insns)
7112 struct epi_info info;
7115 /* If the epilogue is just a single instruction, it must be OK as is. */
7116 if (NEXT_INSN (insns) == NULL_RTX)
7119 /* Otherwise, start a sequence, initialize the information we have, and
7120 process all the insns we were given. */
7123 info.sp_equiv_reg = stack_pointer_rtx;
7125 info.equiv_reg_src = 0;
7127 for (j = 0; j < FIRST_PSEUDO_REGISTER; j++)
7128 info.const_equiv[j] = 0;
7132 while (insn != NULL_RTX)
7134 next = NEXT_INSN (insn);
7143 /* If this insn references the register that SP is equivalent to and
7144 we have a pending load to that register, we must force out the load
7145 first and then indicate we no longer know what SP's equivalent is. */
7146 if (info.equiv_reg_src != 0
7147 && reg_referenced_p (info.sp_equiv_reg, PATTERN (insn)))
7149 emit_equiv_load (&info);
7150 info.sp_equiv_reg = 0;
7153 info.new_sp_equiv_reg = info.sp_equiv_reg;
7154 info.new_sp_offset = info.sp_offset;
7156 /* If this is a (RETURN) and the return address is on the stack,
7157 update the address and change to an indirect jump. */
7158 if (GET_CODE (PATTERN (insn)) == RETURN
7159 || (GET_CODE (PATTERN (insn)) == PARALLEL
7160 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == RETURN))
7162 rtx retaddr = INCOMING_RETURN_ADDR_RTX;
7164 HOST_WIDE_INT offset = 0;
7165 rtx jump_insn, jump_set;
7167 /* If the return address is in a register, we can emit the insn
7168 unchanged. Otherwise, it must be a MEM and we see what the
7169 base register and offset are. In any case, we have to emit any
7170 pending load to the equivalent reg of SP, if any. */
7171 if (REG_P (retaddr))
7173 emit_equiv_load (&info);
7178 else if (GET_CODE (retaddr) == MEM
7179 && REG_P (XEXP (retaddr, 0)))
7180 base = gen_rtx_REG (Pmode, REGNO (XEXP (retaddr, 0))), offset = 0;
7181 else if (GET_CODE (retaddr) == MEM
7182 && GET_CODE (XEXP (retaddr, 0)) == PLUS
7183 && REG_P (XEXP (XEXP (retaddr, 0), 0))
7184 && GET_CODE (XEXP (XEXP (retaddr, 0), 1)) == CONST_INT)
7186 base = gen_rtx_REG (Pmode, REGNO (XEXP (XEXP (retaddr, 0), 0)));
7187 offset = INTVAL (XEXP (XEXP (retaddr, 0), 1));
7192 /* If the base of the location containing the return pointer
7193 is SP, we must update it with the replacement address. Otherwise,
7194 just build the necessary MEM. */
7195 retaddr = plus_constant (base, offset);
7196 if (base == stack_pointer_rtx)
7197 retaddr = simplify_replace_rtx (retaddr, stack_pointer_rtx,
7198 plus_constant (info.sp_equiv_reg,
7201 retaddr = gen_rtx_MEM (Pmode, retaddr);
7203 /* If there is a pending load to the equivalent register for SP
7204 and we reference that register, we must load our address into
7205 a scratch register and then do that load. */
7206 if (info.equiv_reg_src
7207 && reg_overlap_mentioned_p (info.equiv_reg_src, retaddr))
7212 for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
7213 if (HARD_REGNO_MODE_OK (regno, Pmode)
7214 && !fixed_regs[regno]
7215 && TEST_HARD_REG_BIT (regs_invalidated_by_call, regno)
7216 && !REGNO_REG_SET_P (EXIT_BLOCK_PTR->global_live_at_start,
7218 && !refers_to_regno_p (regno,
7219 regno + hard_regno_nregs[regno]
7221 info.equiv_reg_src, NULL)
7222 && info.const_equiv[regno] == 0)
7225 if (regno == FIRST_PSEUDO_REGISTER)
7228 reg = gen_rtx_REG (Pmode, regno);
7229 emit_move_insn (reg, retaddr);
7233 emit_equiv_load (&info);
7234 jump_insn = emit_jump_insn (gen_indirect_jump (retaddr));
7236 /* Show the SET in the above insn is a RETURN. */
7237 jump_set = single_set (jump_insn);
7241 SET_IS_RETURN_P (jump_set) = 1;
7244 /* If SP is not mentioned in the pattern and its equivalent register, if
7245 any, is not modified, just emit it. Otherwise, if neither is set,
7246 replace the reference to SP and emit the insn. If none of those are
7247 true, handle each SET individually. */
7248 else if (!reg_mentioned_p (stack_pointer_rtx, PATTERN (insn))
7249 && (info.sp_equiv_reg == stack_pointer_rtx
7250 || !reg_set_p (info.sp_equiv_reg, insn)))
7252 else if (! reg_set_p (stack_pointer_rtx, insn)
7253 && (info.sp_equiv_reg == stack_pointer_rtx
7254 || !reg_set_p (info.sp_equiv_reg, insn)))
7256 if (! validate_replace_rtx (stack_pointer_rtx,
7257 plus_constant (info.sp_equiv_reg,
7264 else if (GET_CODE (PATTERN (insn)) == SET)
7265 handle_epilogue_set (PATTERN (insn), &info);
7266 else if (GET_CODE (PATTERN (insn)) == PARALLEL)
7268 for (j = 0; j < XVECLEN (PATTERN (insn), 0); j++)
7269 if (GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET)
7270 handle_epilogue_set (XVECEXP (PATTERN (insn), 0, j), &info);
7275 info.sp_equiv_reg = info.new_sp_equiv_reg;
7276 info.sp_offset = info.new_sp_offset;
7278 /* Now update any constants this insn sets. */
7279 note_stores (PATTERN (insn), update_epilogue_consts, &info);
7283 insns = get_insns ();
7288 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
7289 structure that contains information about what we've seen so far. We
7290 process this SET by either updating that data or by emitting one or
7294 handle_epilogue_set (rtx set, struct epi_info *p)
7296 /* First handle the case where we are setting SP. Record what it is being
7297 set from. If unknown, abort. */
7298 if (reg_set_p (stack_pointer_rtx, set))
7300 if (SET_DEST (set) != stack_pointer_rtx)
7303 if (GET_CODE (SET_SRC (set)) == PLUS)
7305 p->new_sp_equiv_reg = XEXP (SET_SRC (set), 0);
7306 if (GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT)
7307 p->new_sp_offset = INTVAL (XEXP (SET_SRC (set), 1));
7308 else if (REG_P (XEXP (SET_SRC (set), 1))
7309 && REGNO (XEXP (SET_SRC (set), 1)) < FIRST_PSEUDO_REGISTER
7310 && p->const_equiv[REGNO (XEXP (SET_SRC (set), 1))] != 0)
7312 = INTVAL (p->const_equiv[REGNO (XEXP (SET_SRC (set), 1))]);
7317 p->new_sp_equiv_reg = SET_SRC (set), p->new_sp_offset = 0;
7319 /* If we are adjusting SP, we adjust from the old data. */
7320 if (p->new_sp_equiv_reg == stack_pointer_rtx)
7322 p->new_sp_equiv_reg = p->sp_equiv_reg;
7323 p->new_sp_offset += p->sp_offset;
7326 if (p->new_sp_equiv_reg == 0 || !REG_P (p->new_sp_equiv_reg))
7332 /* Next handle the case where we are setting SP's equivalent register.
7333 If we already have a value to set it to, abort. We could update, but
7334 there seems little point in handling that case. Note that we have
7335 to allow for the case where we are setting the register set in
7336 the previous part of a PARALLEL inside a single insn. But use the
7337 old offset for any updates within this insn. We must allow for the case
7338 where the register is being set in a different (usually wider) mode than
7340 else if (p->new_sp_equiv_reg != 0 && reg_set_p (p->new_sp_equiv_reg, set))
7342 if (p->equiv_reg_src != 0
7343 || !REG_P (p->new_sp_equiv_reg)
7344 || !REG_P (SET_DEST (set))
7345 || GET_MODE_BITSIZE (GET_MODE (SET_DEST (set))) > BITS_PER_WORD
7346 || REGNO (p->new_sp_equiv_reg) != REGNO (SET_DEST (set)))
7350 = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7351 plus_constant (p->sp_equiv_reg,
7355 /* Otherwise, replace any references to SP in the insn to its new value
7356 and emit the insn. */
7359 SET_SRC (set) = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7360 plus_constant (p->sp_equiv_reg,
7362 SET_DEST (set) = simplify_replace_rtx (SET_DEST (set), stack_pointer_rtx,
7363 plus_constant (p->sp_equiv_reg,
7369 /* Update the tracking information for registers set to constants. */
7372 update_epilogue_consts (rtx dest, rtx x, void *data)
7374 struct epi_info *p = (struct epi_info *) data;
7377 if (!REG_P (dest) || REGNO (dest) >= FIRST_PSEUDO_REGISTER)
7380 /* If we are either clobbering a register or doing a partial set,
7381 show we don't know the value. */
7382 else if (GET_CODE (x) == CLOBBER || ! rtx_equal_p (dest, SET_DEST (x)))
7383 p->const_equiv[REGNO (dest)] = 0;
7385 /* If we are setting it to a constant, record that constant. */
7386 else if (GET_CODE (SET_SRC (x)) == CONST_INT)
7387 p->const_equiv[REGNO (dest)] = SET_SRC (x);
7389 /* If this is a binary operation between a register we have been tracking
7390 and a constant, see if we can compute a new constant value. */
7391 else if (ARITHMETIC_P (SET_SRC (x))
7392 && REG_P (XEXP (SET_SRC (x), 0))
7393 && REGNO (XEXP (SET_SRC (x), 0)) < FIRST_PSEUDO_REGISTER
7394 && p->const_equiv[REGNO (XEXP (SET_SRC (x), 0))] != 0
7395 && GET_CODE (XEXP (SET_SRC (x), 1)) == CONST_INT
7396 && 0 != (new = simplify_binary_operation
7397 (GET_CODE (SET_SRC (x)), GET_MODE (dest),
7398 p->const_equiv[REGNO (XEXP (SET_SRC (x), 0))],
7399 XEXP (SET_SRC (x), 1)))
7400 && GET_CODE (new) == CONST_INT)
7401 p->const_equiv[REGNO (dest)] = new;
7403 /* Otherwise, we can't do anything with this value. */
7405 p->const_equiv[REGNO (dest)] = 0;
7408 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
7411 emit_equiv_load (struct epi_info *p)
7413 if (p->equiv_reg_src != 0)
7415 rtx dest = p->sp_equiv_reg;
7417 if (GET_MODE (p->equiv_reg_src) != GET_MODE (dest))
7418 dest = gen_rtx_REG (GET_MODE (p->equiv_reg_src),
7419 REGNO (p->sp_equiv_reg));
7421 emit_move_insn (dest, p->equiv_reg_src);
7422 p->equiv_reg_src = 0;
7427 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7428 this into place with notes indicating where the prologue ends and where
7429 the epilogue begins. Update the basic block information when possible. */
7432 thread_prologue_and_epilogue_insns (rtx f ATTRIBUTE_UNUSED)
7436 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
7439 #ifdef HAVE_prologue
7440 rtx prologue_end = NULL_RTX;
7442 #if defined (HAVE_epilogue) || defined(HAVE_return)
7443 rtx epilogue_end = NULL_RTX;
7446 #ifdef HAVE_prologue
7450 seq = gen_prologue ();
7453 /* Retain a map of the prologue insns. */
7454 record_insns (seq, &prologue);
7455 prologue_end = emit_note (NOTE_INSN_PROLOGUE_END);
7459 set_insn_locators (seq, prologue_locator);
7461 /* Can't deal with multiple successors of the entry block
7462 at the moment. Function should always have at least one
7464 if (!ENTRY_BLOCK_PTR->succ || ENTRY_BLOCK_PTR->succ->succ_next)
7467 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
7472 /* If the exit block has no non-fake predecessors, we don't need
7474 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7475 if ((e->flags & EDGE_FAKE) == 0)
7481 if (optimize && HAVE_return)
7483 /* If we're allowed to generate a simple return instruction,
7484 then by definition we don't need a full epilogue. Examine
7485 the block that falls through to EXIT. If it does not
7486 contain any code, examine its predecessors and try to
7487 emit (conditional) return instructions. */
7493 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7494 if (e->flags & EDGE_FALLTHRU)
7500 /* Verify that there are no active instructions in the last block. */
7501 label = BB_END (last);
7502 while (label && GET_CODE (label) != CODE_LABEL)
7504 if (active_insn_p (label))
7506 label = PREV_INSN (label);
7509 if (BB_HEAD (last) == label && GET_CODE (label) == CODE_LABEL)
7511 rtx epilogue_line_note = NULL_RTX;
7513 /* Locate the line number associated with the closing brace,
7514 if we can find one. */
7515 for (seq = get_last_insn ();
7516 seq && ! active_insn_p (seq);
7517 seq = PREV_INSN (seq))
7518 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
7520 epilogue_line_note = seq;
7524 for (e = last->pred; e; e = e_next)
7526 basic_block bb = e->src;
7529 e_next = e->pred_next;
7530 if (bb == ENTRY_BLOCK_PTR)
7534 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
7537 /* If we have an unconditional jump, we can replace that
7538 with a simple return instruction. */
7539 if (simplejump_p (jump))
7541 emit_return_into_block (bb, epilogue_line_note);
7545 /* If we have a conditional jump, we can try to replace
7546 that with a conditional return instruction. */
7547 else if (condjump_p (jump))
7549 if (! redirect_jump (jump, 0, 0))
7552 /* If this block has only one successor, it both jumps
7553 and falls through to the fallthru block, so we can't
7555 if (bb->succ->succ_next == NULL)
7561 /* Fix up the CFG for the successful change we just made. */
7562 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7565 /* Emit a return insn for the exit fallthru block. Whether
7566 this is still reachable will be determined later. */
7568 emit_barrier_after (BB_END (last));
7569 emit_return_into_block (last, epilogue_line_note);
7570 epilogue_end = BB_END (last);
7571 last->succ->flags &= ~EDGE_FALLTHRU;
7576 /* Find the edge that falls through to EXIT. Other edges may exist
7577 due to RETURN instructions, but those don't need epilogues.
7578 There really shouldn't be a mixture -- either all should have
7579 been converted or none, however... */
7581 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7582 if (e->flags & EDGE_FALLTHRU)
7587 #ifdef HAVE_epilogue
7591 epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG);
7593 seq = gen_epilogue ();
7595 #ifdef INCOMING_RETURN_ADDR_RTX
7596 /* If this function returns with the stack depressed and we can support
7597 it, massage the epilogue to actually do that. */
7598 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7599 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7600 seq = keep_stack_depressed (seq);
7603 emit_jump_insn (seq);
7605 /* Retain a map of the epilogue insns. */
7606 record_insns (seq, &epilogue);
7607 set_insn_locators (seq, epilogue_locator);
7612 insert_insn_on_edge (seq, e);
7620 if (! next_active_insn (BB_END (e->src)))
7622 /* We have a fall-through edge to the exit block, the source is not
7623 at the end of the function, and there will be an assembler epilogue
7624 at the end of the function.
7625 We can't use force_nonfallthru here, because that would try to
7626 use return. Inserting a jump 'by hand' is extremely messy, so
7627 we take advantage of cfg_layout_finalize using
7628 fixup_fallthru_exit_predecessor. */
7629 cfg_layout_initialize ();
7630 FOR_EACH_BB (cur_bb)
7631 if (cur_bb->index >= 0 && cur_bb->next_bb->index >= 0)
7632 cur_bb->rbi->next = cur_bb->next_bb;
7633 cfg_layout_finalize ();
7638 commit_edge_insertions ();
7640 #ifdef HAVE_sibcall_epilogue
7641 /* Emit sibling epilogues before any sibling call sites. */
7642 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7644 basic_block bb = e->src;
7645 rtx insn = BB_END (bb);
7649 if (GET_CODE (insn) != CALL_INSN
7650 || ! SIBLING_CALL_P (insn))
7654 emit_insn (gen_sibcall_epilogue ());
7658 /* Retain a map of the epilogue insns. Used in life analysis to
7659 avoid getting rid of sibcall epilogue insns. Do this before we
7660 actually emit the sequence. */
7661 record_insns (seq, &sibcall_epilogue);
7662 set_insn_locators (seq, epilogue_locator);
7664 i = PREV_INSN (insn);
7665 newinsn = emit_insn_before (seq, insn);
7669 #ifdef HAVE_prologue
7670 /* This is probably all useless now that we use locators. */
7675 /* GDB handles `break f' by setting a breakpoint on the first
7676 line note after the prologue. Which means (1) that if
7677 there are line number notes before where we inserted the
7678 prologue we should move them, and (2) we should generate a
7679 note before the end of the first basic block, if there isn't
7682 ??? This behavior is completely broken when dealing with
7683 multiple entry functions. We simply place the note always
7684 into first basic block and let alternate entry points
7688 for (insn = prologue_end; insn; insn = prev)
7690 prev = PREV_INSN (insn);
7691 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7693 /* Note that we cannot reorder the first insn in the
7694 chain, since rest_of_compilation relies on that
7695 remaining constant. */
7698 reorder_insns (insn, insn, prologue_end);
7702 /* Find the last line number note in the first block. */
7703 for (insn = BB_END (ENTRY_BLOCK_PTR->next_bb);
7704 insn != prologue_end && insn;
7705 insn = PREV_INSN (insn))
7706 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7709 /* If we didn't find one, make a copy of the first line number
7713 for (insn = next_active_insn (prologue_end);
7715 insn = PREV_INSN (insn))
7716 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7718 emit_note_copy_after (insn, prologue_end);
7724 #ifdef HAVE_epilogue
7729 /* Similarly, move any line notes that appear after the epilogue.
7730 There is no need, however, to be quite so anal about the existence
7731 of such a note. Also move the NOTE_INSN_FUNCTION_END and (possibly)
7732 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
7734 for (insn = epilogue_end; insn; insn = next)
7736 next = NEXT_INSN (insn);
7737 if (GET_CODE (insn) == NOTE
7738 && (NOTE_LINE_NUMBER (insn) > 0
7739 || NOTE_LINE_NUMBER (insn) == NOTE_INSN_FUNCTION_BEG
7740 || NOTE_LINE_NUMBER (insn) == NOTE_INSN_FUNCTION_END))
7741 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7747 /* Reposition the prologue-end and epilogue-begin notes after instruction
7748 scheduling and delayed branch scheduling. */
7751 reposition_prologue_and_epilogue_notes (rtx f ATTRIBUTE_UNUSED)
7753 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7754 rtx insn, last, note;
7757 if ((len = VARRAY_SIZE (prologue)) > 0)
7761 /* Scan from the beginning until we reach the last prologue insn.
7762 We apparently can't depend on basic_block_{head,end} after
7764 for (insn = f; insn; insn = NEXT_INSN (insn))
7766 if (GET_CODE (insn) == NOTE)
7768 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
7771 else if (contains (insn, prologue))
7781 /* Find the prologue-end note if we haven't already, and
7782 move it to just after the last prologue insn. */
7785 for (note = last; (note = NEXT_INSN (note));)
7786 if (GET_CODE (note) == NOTE
7787 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
7791 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
7792 if (GET_CODE (last) == CODE_LABEL)
7793 last = NEXT_INSN (last);
7794 reorder_insns (note, note, last);
7798 if ((len = VARRAY_SIZE (epilogue)) > 0)
7802 /* Scan from the end until we reach the first epilogue insn.
7803 We apparently can't depend on basic_block_{head,end} after
7805 for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
7807 if (GET_CODE (insn) == NOTE)
7809 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
7812 else if (contains (insn, epilogue))
7822 /* Find the epilogue-begin note if we haven't already, and
7823 move it to just before the first epilogue insn. */
7826 for (note = insn; (note = PREV_INSN (note));)
7827 if (GET_CODE (note) == NOTE
7828 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
7832 if (PREV_INSN (last) != note)
7833 reorder_insns (note, note, PREV_INSN (last));
7836 #endif /* HAVE_prologue or HAVE_epilogue */
7839 /* Called once, at initialization, to initialize function.c. */
7842 init_function_once (void)
7844 VARRAY_INT_INIT (prologue, 0, "prologue");
7845 VARRAY_INT_INIT (epilogue, 0, "epilogue");
7846 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");
7849 /* Resets insn_block_boundaries array. */
7852 reset_block_changes (void)
7854 VARRAY_TREE_INIT (cfun->ib_boundaries_block, 100, "ib_boundaries_block");
7855 VARRAY_PUSH_TREE (cfun->ib_boundaries_block, NULL_TREE);
7858 /* Record the boundary for BLOCK. */
7860 record_block_change (tree block)
7868 last_block = VARRAY_TOP_TREE (cfun->ib_boundaries_block);
7869 VARRAY_POP (cfun->ib_boundaries_block);
7871 for (i = VARRAY_ACTIVE_SIZE (cfun->ib_boundaries_block); i < n; i++)
7872 VARRAY_PUSH_TREE (cfun->ib_boundaries_block, last_block);
7874 VARRAY_PUSH_TREE (cfun->ib_boundaries_block, block);
7877 /* Finishes record of boundaries. */
7878 void finalize_block_changes (void)
7880 record_block_change (DECL_INITIAL (current_function_decl));
7883 /* For INSN return the BLOCK it belongs to. */
7885 check_block_change (rtx insn, tree *block)
7887 unsigned uid = INSN_UID (insn);
7889 if (uid >= VARRAY_ACTIVE_SIZE (cfun->ib_boundaries_block))
7892 *block = VARRAY_TREE (cfun->ib_boundaries_block, uid);
7895 /* Releases the ib_boundaries_block records. */
7897 free_block_changes (void)
7899 cfun->ib_boundaries_block = NULL;
7902 /* Returns the name of the current function. */
7904 current_function_name (void)
7906 return lang_hooks.decl_printable_name (cfun->decl, 2);
7909 #include "gt-function.h"