1 /* Control flow graph manipulation code for GNU compiler.
2 Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
4 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
22 /* This file contains low level functions to manipulate the CFG and analyze it
23 that are aware of the RTL intermediate language.
25 Available functionality:
26 - Basic CFG/RTL manipulation API documented in cfghooks.h
27 - CFG-aware instruction chain manipulation
28 delete_insn, delete_insn_chain
29 - Edge splitting and committing to edges
30 insert_insn_on_edge, commit_edge_insertions
31 - CFG updating after insn simplification
32 purge_dead_edges, purge_all_dead_edges
34 Functions not supposed for generic use:
35 - Infrastructure to determine quickly basic block for insn
36 compute_bb_for_insn, update_bb_for_insn, set_block_for_insn,
37 - Edge redirection with updating and optimizing of insn chain
38 block_label, tidy_fallthru_edge, force_nonfallthru */
42 #include "coretypes.h"
45 #include "hard-reg-set.h"
46 #include "basic-block.h"
52 #include "rtl-error.h"
55 #include "insn-attr.h"
56 #include "insn-config.h"
57 #include "cfglayout.h"
62 #include "tree-pass.h"
65 static int can_delete_note_p (const_rtx
);
66 static int can_delete_label_p (const_rtx
);
67 static basic_block
rtl_split_edge (edge
);
68 static bool rtl_move_block_after (basic_block
, basic_block
);
69 static int rtl_verify_flow_info (void);
70 static basic_block
cfg_layout_split_block (basic_block
, void *);
71 static edge
cfg_layout_redirect_edge_and_branch (edge
, basic_block
);
72 static basic_block
cfg_layout_redirect_edge_and_branch_force (edge
, basic_block
);
73 static void cfg_layout_delete_block (basic_block
);
74 static void rtl_delete_block (basic_block
);
75 static basic_block
rtl_redirect_edge_and_branch_force (edge
, basic_block
);
76 static edge
rtl_redirect_edge_and_branch (edge
, basic_block
);
77 static basic_block
rtl_split_block (basic_block
, void *);
78 static void rtl_dump_bb (basic_block
, FILE *, int, int);
79 static int rtl_verify_flow_info_1 (void);
80 static void rtl_make_forwarder_block (edge
);
82 /* Return true if NOTE is not one of the ones that must be kept paired,
83 so that we may simply delete it. */
86 can_delete_note_p (const_rtx note
)
88 switch (NOTE_KIND (note
))
90 case NOTE_INSN_DELETED
:
91 case NOTE_INSN_BASIC_BLOCK
:
92 case NOTE_INSN_EPILOGUE_BEG
:
100 /* True if a given label can be deleted. */
103 can_delete_label_p (const_rtx label
)
105 return (!LABEL_PRESERVE_P (label
)
106 /* User declared labels must be preserved. */
107 && LABEL_NAME (label
) == 0
108 && !in_expr_list_p (forced_labels
, label
));
111 /* Delete INSN by patching it out. Return the next insn. */
114 delete_insn (rtx insn
)
116 rtx next
= NEXT_INSN (insn
);
118 bool really_delete
= true;
122 /* Some labels can't be directly removed from the INSN chain, as they
123 might be references via variables, constant pool etc.
124 Convert them to the special NOTE_INSN_DELETED_LABEL note. */
125 if (! can_delete_label_p (insn
))
127 const char *name
= LABEL_NAME (insn
);
129 really_delete
= false;
130 PUT_CODE (insn
, NOTE
);
131 NOTE_KIND (insn
) = NOTE_INSN_DELETED_LABEL
;
132 NOTE_DELETED_LABEL_NAME (insn
) = name
;
135 remove_node_from_expr_list (insn
, &nonlocal_goto_handler_labels
);
140 /* If this insn has already been deleted, something is very wrong. */
141 gcc_assert (!INSN_DELETED_P (insn
));
143 INSN_DELETED_P (insn
) = 1;
146 /* If deleting a jump, decrement the use count of the label. Deleting
147 the label itself should happen in the normal course of block merging. */
150 if (JUMP_LABEL (insn
)
151 && LABEL_P (JUMP_LABEL (insn
)))
152 LABEL_NUSES (JUMP_LABEL (insn
))--;
154 /* If there are more targets, remove them too. */
156 = find_reg_note (insn
, REG_LABEL_TARGET
, NULL_RTX
)) != NULL_RTX
157 && LABEL_P (XEXP (note
, 0)))
159 LABEL_NUSES (XEXP (note
, 0))--;
160 remove_note (insn
, note
);
164 /* Also if deleting any insn that references a label as an operand. */
165 while ((note
= find_reg_note (insn
, REG_LABEL_OPERAND
, NULL_RTX
)) != NULL_RTX
166 && LABEL_P (XEXP (note
, 0)))
168 LABEL_NUSES (XEXP (note
, 0))--;
169 remove_note (insn
, note
);
172 if (JUMP_TABLE_DATA_P (insn
))
174 rtx pat
= PATTERN (insn
);
175 int diff_vec_p
= GET_CODE (PATTERN (insn
)) == ADDR_DIFF_VEC
;
176 int len
= XVECLEN (pat
, diff_vec_p
);
179 for (i
= 0; i
< len
; i
++)
181 rtx label
= XEXP (XVECEXP (pat
, diff_vec_p
, i
), 0);
183 /* When deleting code in bulk (e.g. removing many unreachable
184 blocks) we can delete a label that's a target of the vector
185 before deleting the vector itself. */
187 LABEL_NUSES (label
)--;
194 /* Like delete_insn but also purge dead edges from BB. */
197 delete_insn_and_edges (rtx insn
)
203 && BLOCK_FOR_INSN (insn
)
204 && BB_END (BLOCK_FOR_INSN (insn
)) == insn
)
206 x
= delete_insn (insn
);
208 purge_dead_edges (BLOCK_FOR_INSN (insn
));
212 /* Unlink a chain of insns between START and FINISH, leaving notes
213 that must be paired. If CLEAR_BB is true, we set bb field for
214 insns that cannot be removed to NULL. */
217 delete_insn_chain (rtx start
, rtx finish
, bool clear_bb
)
221 /* Unchain the insns one by one. It would be quicker to delete all of these
222 with a single unchaining, rather than one at a time, but we need to keep
226 next
= NEXT_INSN (start
);
227 if (NOTE_P (start
) && !can_delete_note_p (start
))
230 next
= delete_insn (start
);
232 if (clear_bb
&& !INSN_DELETED_P (start
))
233 set_block_for_insn (start
, NULL
);
241 /* Create a new basic block consisting of the instructions between HEAD and END
242 inclusive. This function is designed to allow fast BB construction - reuses
243 the note and basic block struct in BB_NOTE, if any and do not grow
244 BASIC_BLOCK chain and should be used directly only by CFG construction code.
245 END can be NULL in to create new empty basic block before HEAD. Both END
246 and HEAD can be NULL to create basic block at the end of INSN chain.
247 AFTER is the basic block we should be put after. */
250 create_basic_block_structure (rtx head
, rtx end
, rtx bb_note
, basic_block after
)
255 && (bb
= NOTE_BASIC_BLOCK (bb_note
)) != NULL
258 /* If we found an existing note, thread it back onto the chain. */
266 after
= PREV_INSN (head
);
270 if (after
!= bb_note
&& NEXT_INSN (after
) != bb_note
)
271 reorder_insns_nobb (bb_note
, bb_note
, after
);
275 /* Otherwise we must create a note and a basic block structure. */
279 init_rtl_bb_info (bb
);
282 = emit_note_after (NOTE_INSN_BASIC_BLOCK
, get_last_insn ());
283 else if (LABEL_P (head
) && end
)
285 bb_note
= emit_note_after (NOTE_INSN_BASIC_BLOCK
, head
);
291 bb_note
= emit_note_before (NOTE_INSN_BASIC_BLOCK
, head
);
297 NOTE_BASIC_BLOCK (bb_note
) = bb
;
300 /* Always include the bb note in the block. */
301 if (NEXT_INSN (end
) == bb_note
)
306 bb
->index
= last_basic_block
++;
307 bb
->flags
= BB_NEW
| BB_RTL
;
308 link_block (bb
, after
);
309 SET_BASIC_BLOCK (bb
->index
, bb
);
310 df_bb_refs_record (bb
->index
, false);
311 update_bb_for_insn (bb
);
312 BB_SET_PARTITION (bb
, BB_UNPARTITIONED
);
314 /* Tag the block so that we know it has been used when considering
315 other basic block notes. */
321 /* Create new basic block consisting of instructions in between HEAD and END
322 and place it to the BB chain after block AFTER. END can be NULL in to
323 create new empty basic block before HEAD. Both END and HEAD can be NULL to
324 create basic block at the end of INSN chain. */
327 rtl_create_basic_block (void *headp
, void *endp
, basic_block after
)
329 rtx head
= (rtx
) headp
, end
= (rtx
) endp
;
332 /* Grow the basic block array if needed. */
333 if ((size_t) last_basic_block
>= VEC_length (basic_block
, basic_block_info
))
335 size_t new_size
= last_basic_block
+ (last_basic_block
+ 3) / 4;
336 VEC_safe_grow_cleared (basic_block
, gc
, basic_block_info
, new_size
);
341 bb
= create_basic_block_structure (head
, end
, NULL
, after
);
347 cfg_layout_create_basic_block (void *head
, void *end
, basic_block after
)
349 basic_block newbb
= rtl_create_basic_block (head
, end
, after
);
354 /* Delete the insns in a (non-live) block. We physically delete every
355 non-deleted-note insn, and update the flow graph appropriately.
357 Return nonzero if we deleted an exception handler. */
359 /* ??? Preserving all such notes strikes me as wrong. It would be nice
360 to post-process the stream to remove empty blocks, loops, ranges, etc. */
363 rtl_delete_block (basic_block b
)
367 /* If the head of this block is a CODE_LABEL, then it might be the
368 label for an exception handler which can't be reached. We need
369 to remove the label from the exception_handler_label list. */
372 end
= get_last_bb_insn (b
);
374 /* Selectively delete the entire chain. */
376 delete_insn_chain (insn
, end
, true);
380 fprintf (dump_file
, "deleting block %d\n", b
->index
);
381 df_bb_delete (b
->index
);
384 /* Records the basic block struct in BLOCK_FOR_INSN for every insn. */
387 compute_bb_for_insn (void)
393 rtx end
= BB_END (bb
);
396 for (insn
= BB_HEAD (bb
); ; insn
= NEXT_INSN (insn
))
398 BLOCK_FOR_INSN (insn
) = bb
;
405 /* Release the basic_block_for_insn array. */
408 free_bb_for_insn (void)
411 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
412 if (!BARRIER_P (insn
))
413 BLOCK_FOR_INSN (insn
) = NULL
;
418 rest_of_pass_free_cfg (void)
421 /* The resource.c machinery uses DF but the CFG isn't guaranteed to be
422 valid at that point so it would be too late to call df_analyze. */
423 if (optimize
> 0 && flag_delayed_branch
)
425 df_note_add_problem ();
434 struct rtl_opt_pass pass_free_cfg
=
438 "*free_cfg", /* name */
440 rest_of_pass_free_cfg
, /* execute */
443 0, /* static_pass_number */
445 0, /* properties_required */
446 0, /* properties_provided */
447 PROP_cfg
, /* properties_destroyed */
448 0, /* todo_flags_start */
449 0, /* todo_flags_finish */
453 /* Return RTX to emit after when we want to emit code on the entry of function. */
455 entry_of_function (void)
457 return (n_basic_blocks
> NUM_FIXED_BLOCKS
?
458 BB_HEAD (ENTRY_BLOCK_PTR
->next_bb
) : get_insns ());
461 /* Emit INSN at the entry point of the function, ensuring that it is only
462 executed once per function. */
464 emit_insn_at_entry (rtx insn
)
466 edge_iterator ei
= ei_start (ENTRY_BLOCK_PTR
->succs
);
467 edge e
= ei_safe_edge (ei
);
468 gcc_assert (e
->flags
& EDGE_FALLTHRU
);
470 insert_insn_on_edge (insn
, e
);
471 commit_edge_insertions ();
474 /* Update BLOCK_FOR_INSN of insns between BEGIN and END
475 (or BARRIER if found) and notify df of the bb change.
476 The insn chain range is inclusive
477 (i.e. both BEGIN and END will be updated. */
480 update_bb_for_insn_chain (rtx begin
, rtx end
, basic_block bb
)
484 end
= NEXT_INSN (end
);
485 for (insn
= begin
; insn
!= end
; insn
= NEXT_INSN (insn
))
486 if (!BARRIER_P (insn
))
487 df_insn_change_bb (insn
, bb
);
490 /* Update BLOCK_FOR_INSN of insns in BB to BB,
491 and notify df of the change. */
494 update_bb_for_insn (basic_block bb
)
496 update_bb_for_insn_chain (BB_HEAD (bb
), BB_END (bb
), bb
);
500 /* Return the INSN immediately following the NOTE_INSN_BASIC_BLOCK
501 note associated with the BLOCK. */
504 first_insn_after_basic_block_note (basic_block block
)
508 /* Get the first instruction in the block. */
509 insn
= BB_HEAD (block
);
511 if (insn
== NULL_RTX
)
514 insn
= NEXT_INSN (insn
);
515 gcc_assert (NOTE_INSN_BASIC_BLOCK_P (insn
));
517 return NEXT_INSN (insn
);
520 /* Creates a new basic block just after basic block B by splitting
521 everything after specified instruction I. */
524 rtl_split_block (basic_block bb
, void *insnp
)
527 rtx insn
= (rtx
) insnp
;
533 insn
= first_insn_after_basic_block_note (bb
);
539 insn
= PREV_INSN (insn
);
541 /* If the block contains only debug insns, insn would have
542 been NULL in a non-debug compilation, and then we'd end
543 up emitting a DELETED note. For -fcompare-debug
544 stability, emit the note too. */
545 if (insn
!= BB_END (bb
)
546 && DEBUG_INSN_P (next
)
547 && DEBUG_INSN_P (BB_END (bb
)))
549 while (next
!= BB_END (bb
) && DEBUG_INSN_P (next
))
550 next
= NEXT_INSN (next
);
552 if (next
== BB_END (bb
))
553 emit_note_after (NOTE_INSN_DELETED
, next
);
557 insn
= get_last_insn ();
560 /* We probably should check type of the insn so that we do not create
561 inconsistent cfg. It is checked in verify_flow_info anyway, so do not
563 if (insn
== BB_END (bb
))
564 emit_note_after (NOTE_INSN_DELETED
, insn
);
566 /* Create the new basic block. */
567 new_bb
= create_basic_block (NEXT_INSN (insn
), BB_END (bb
), bb
);
568 BB_COPY_PARTITION (new_bb
, bb
);
571 /* Redirect the outgoing edges. */
572 new_bb
->succs
= bb
->succs
;
574 FOR_EACH_EDGE (e
, ei
, new_bb
->succs
)
577 /* The new block starts off being dirty. */
578 df_set_bb_dirty (bb
);
582 /* Blocks A and B are to be merged into a single block A. The insns
583 are already contiguous. */
586 rtl_merge_blocks (basic_block a
, basic_block b
)
588 rtx b_head
= BB_HEAD (b
), b_end
= BB_END (b
), a_end
= BB_END (a
);
589 rtx del_first
= NULL_RTX
, del_last
= NULL_RTX
;
590 rtx b_debug_start
= b_end
, b_debug_end
= b_end
;
594 fprintf (dump_file
, "merging block %d into block %d\n", b
->index
, a
->index
);
596 while (DEBUG_INSN_P (b_end
))
597 b_end
= PREV_INSN (b_debug_start
= b_end
);
599 /* If there was a CODE_LABEL beginning B, delete it. */
600 if (LABEL_P (b_head
))
602 /* Detect basic blocks with nothing but a label. This can happen
603 in particular at the end of a function. */
607 del_first
= del_last
= b_head
;
608 b_head
= NEXT_INSN (b_head
);
611 /* Delete the basic block note and handle blocks containing just that
613 if (NOTE_INSN_BASIC_BLOCK_P (b_head
))
621 b_head
= NEXT_INSN (b_head
);
624 /* If there was a jump out of A, delete it. */
629 for (prev
= PREV_INSN (a_end
); ; prev
= PREV_INSN (prev
))
631 || NOTE_INSN_BASIC_BLOCK_P (prev
)
632 || prev
== BB_HEAD (a
))
638 /* If this was a conditional jump, we need to also delete
639 the insn that set cc0. */
640 if (only_sets_cc0_p (prev
))
644 prev
= prev_nonnote_insn (prev
);
651 a_end
= PREV_INSN (del_first
);
653 else if (BARRIER_P (NEXT_INSN (a_end
)))
654 del_first
= NEXT_INSN (a_end
);
656 /* Delete everything marked above as well as crap that might be
657 hanging out between the two blocks. */
659 delete_insn_chain (del_first
, del_last
, true);
661 /* Reassociate the insns of B with A. */
664 update_bb_for_insn_chain (a_end
, b_debug_end
, a
);
668 else if (b_end
!= b_debug_end
)
670 /* Move any deleted labels and other notes between the end of A
671 and the debug insns that make up B after the debug insns,
672 bringing the debug insns into A while keeping the notes after
674 if (NEXT_INSN (a_end
) != b_debug_start
)
675 reorder_insns_nobb (NEXT_INSN (a_end
), PREV_INSN (b_debug_start
),
677 update_bb_for_insn_chain (b_debug_start
, b_debug_end
, a
);
681 df_bb_delete (b
->index
);
686 /* Return true when block A and B can be merged. */
689 rtl_can_merge_blocks (basic_block a
, basic_block b
)
691 /* If we are partitioning hot/cold basic blocks, we don't want to
692 mess up unconditional or indirect jumps that cross between hot
695 Basic block partitioning may result in some jumps that appear to
696 be optimizable (or blocks that appear to be mergeable), but which really
697 must be left untouched (they are required to make it safely across
698 partition boundaries). See the comments at the top of
699 bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */
701 if (BB_PARTITION (a
) != BB_PARTITION (b
))
704 /* There must be exactly one edge in between the blocks. */
705 return (single_succ_p (a
)
706 && single_succ (a
) == b
709 /* Must be simple edge. */
710 && !(single_succ_edge (a
)->flags
& EDGE_COMPLEX
)
712 && a
!= ENTRY_BLOCK_PTR
&& b
!= EXIT_BLOCK_PTR
713 /* If the jump insn has side effects,
714 we can't kill the edge. */
715 && (!JUMP_P (BB_END (a
))
717 ? simplejump_p (BB_END (a
)) : onlyjump_p (BB_END (a
)))));
720 /* Return the label in the head of basic block BLOCK. Create one if it doesn't
724 block_label (basic_block block
)
726 if (block
== EXIT_BLOCK_PTR
)
729 if (!LABEL_P (BB_HEAD (block
)))
731 BB_HEAD (block
) = emit_label_before (gen_label_rtx (), BB_HEAD (block
));
734 return BB_HEAD (block
);
737 /* Attempt to perform edge redirection by replacing possibly complex jump
738 instruction by unconditional jump or removing jump completely. This can
739 apply only if all edges now point to the same block. The parameters and
740 return values are equivalent to redirect_edge_and_branch. */
743 try_redirect_by_replacing_jump (edge e
, basic_block target
, bool in_cfglayout
)
745 basic_block src
= e
->src
;
746 rtx insn
= BB_END (src
), kill_from
;
750 /* If we are partitioning hot/cold basic blocks, we don't want to
751 mess up unconditional or indirect jumps that cross between hot
754 Basic block partitioning may result in some jumps that appear to
755 be optimizable (or blocks that appear to be mergeable), but which really
756 must be left untouched (they are required to make it safely across
757 partition boundaries). See the comments at the top of
758 bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */
760 if (find_reg_note (insn
, REG_CROSSING_JUMP
, NULL_RTX
)
761 || BB_PARTITION (src
) != BB_PARTITION (target
))
764 /* We can replace or remove a complex jump only when we have exactly
765 two edges. Also, if we have exactly one outgoing edge, we can
767 if (EDGE_COUNT (src
->succs
) >= 3
768 /* Verify that all targets will be TARGET. Specifically, the
769 edge that is not E must also go to TARGET. */
770 || (EDGE_COUNT (src
->succs
) == 2
771 && EDGE_SUCC (src
, EDGE_SUCC (src
, 0) == e
)->dest
!= target
))
774 if (!onlyjump_p (insn
))
776 if ((!optimize
|| reload_completed
) && tablejump_p (insn
, NULL
, NULL
))
779 /* Avoid removing branch with side effects. */
780 set
= single_set (insn
);
781 if (!set
|| side_effects_p (set
))
784 /* In case we zap a conditional jump, we'll need to kill
785 the cc0 setter too. */
788 if (reg_mentioned_p (cc0_rtx
, PATTERN (insn
))
789 && only_sets_cc0_p (PREV_INSN (insn
)))
790 kill_from
= PREV_INSN (insn
);
793 /* See if we can create the fallthru edge. */
794 if (in_cfglayout
|| can_fallthru (src
, target
))
797 fprintf (dump_file
, "Removing jump %i.\n", INSN_UID (insn
));
800 /* Selectively unlink whole insn chain. */
803 rtx insn
= src
->il
.rtl
->footer
;
805 delete_insn_chain (kill_from
, BB_END (src
), false);
807 /* Remove barriers but keep jumptables. */
810 if (BARRIER_P (insn
))
812 if (PREV_INSN (insn
))
813 NEXT_INSN (PREV_INSN (insn
)) = NEXT_INSN (insn
);
815 src
->il
.rtl
->footer
= NEXT_INSN (insn
);
816 if (NEXT_INSN (insn
))
817 PREV_INSN (NEXT_INSN (insn
)) = PREV_INSN (insn
);
821 insn
= NEXT_INSN (insn
);
825 delete_insn_chain (kill_from
, PREV_INSN (BB_HEAD (target
)),
829 /* If this already is simplejump, redirect it. */
830 else if (simplejump_p (insn
))
832 if (e
->dest
== target
)
835 fprintf (dump_file
, "Redirecting jump %i from %i to %i.\n",
836 INSN_UID (insn
), e
->dest
->index
, target
->index
);
837 if (!redirect_jump (insn
, block_label (target
), 0))
839 gcc_assert (target
== EXIT_BLOCK_PTR
);
844 /* Cannot do anything for target exit block. */
845 else if (target
== EXIT_BLOCK_PTR
)
848 /* Or replace possibly complicated jump insn by simple jump insn. */
851 rtx target_label
= block_label (target
);
852 rtx barrier
, label
, table
;
854 emit_jump_insn_after_noloc (gen_jump (target_label
), insn
);
855 JUMP_LABEL (BB_END (src
)) = target_label
;
856 LABEL_NUSES (target_label
)++;
858 fprintf (dump_file
, "Replacing insn %i by jump %i\n",
859 INSN_UID (insn
), INSN_UID (BB_END (src
)));
862 delete_insn_chain (kill_from
, insn
, false);
864 /* Recognize a tablejump that we are converting to a
865 simple jump and remove its associated CODE_LABEL
866 and ADDR_VEC or ADDR_DIFF_VEC. */
867 if (tablejump_p (insn
, &label
, &table
))
868 delete_insn_chain (label
, table
, false);
870 barrier
= next_nonnote_insn (BB_END (src
));
871 if (!barrier
|| !BARRIER_P (barrier
))
872 emit_barrier_after (BB_END (src
));
875 if (barrier
!= NEXT_INSN (BB_END (src
)))
877 /* Move the jump before barrier so that the notes
878 which originally were or were created before jump table are
879 inside the basic block. */
880 rtx new_insn
= BB_END (src
);
882 update_bb_for_insn_chain (NEXT_INSN (BB_END (src
)),
883 PREV_INSN (barrier
), src
);
885 NEXT_INSN (PREV_INSN (new_insn
)) = NEXT_INSN (new_insn
);
886 PREV_INSN (NEXT_INSN (new_insn
)) = PREV_INSN (new_insn
);
888 NEXT_INSN (new_insn
) = barrier
;
889 NEXT_INSN (PREV_INSN (barrier
)) = new_insn
;
891 PREV_INSN (new_insn
) = PREV_INSN (barrier
);
892 PREV_INSN (barrier
) = new_insn
;
897 /* Keep only one edge out and set proper flags. */
898 if (!single_succ_p (src
))
900 gcc_assert (single_succ_p (src
));
902 e
= single_succ_edge (src
);
904 e
->flags
= EDGE_FALLTHRU
;
908 e
->probability
= REG_BR_PROB_BASE
;
909 e
->count
= src
->count
;
911 if (e
->dest
!= target
)
912 redirect_edge_succ (e
, target
);
916 /* Subroutine of redirect_branch_edge that tries to patch the jump
917 instruction INSN so that it reaches block NEW. Do this
918 only when it originally reached block OLD. Return true if this
919 worked or the original target wasn't OLD, return false if redirection
923 patch_jump_insn (rtx insn
, rtx old_label
, basic_block new_bb
)
926 /* Recognize a tablejump and adjust all matching cases. */
927 if (tablejump_p (insn
, NULL
, &tmp
))
931 rtx new_label
= block_label (new_bb
);
933 if (new_bb
== EXIT_BLOCK_PTR
)
935 if (GET_CODE (PATTERN (tmp
)) == ADDR_VEC
)
936 vec
= XVEC (PATTERN (tmp
), 0);
938 vec
= XVEC (PATTERN (tmp
), 1);
940 for (j
= GET_NUM_ELEM (vec
) - 1; j
>= 0; --j
)
941 if (XEXP (RTVEC_ELT (vec
, j
), 0) == old_label
)
943 RTVEC_ELT (vec
, j
) = gen_rtx_LABEL_REF (Pmode
, new_label
);
944 --LABEL_NUSES (old_label
);
945 ++LABEL_NUSES (new_label
);
948 /* Handle casesi dispatch insns. */
949 if ((tmp
= single_set (insn
)) != NULL
950 && SET_DEST (tmp
) == pc_rtx
951 && GET_CODE (SET_SRC (tmp
)) == IF_THEN_ELSE
952 && GET_CODE (XEXP (SET_SRC (tmp
), 2)) == LABEL_REF
953 && XEXP (XEXP (SET_SRC (tmp
), 2), 0) == old_label
)
955 XEXP (SET_SRC (tmp
), 2) = gen_rtx_LABEL_REF (Pmode
,
957 --LABEL_NUSES (old_label
);
958 ++LABEL_NUSES (new_label
);
961 else if ((tmp
= extract_asm_operands (PATTERN (insn
))) != NULL
)
963 int i
, n
= ASM_OPERANDS_LABEL_LENGTH (tmp
);
966 if (new_bb
== EXIT_BLOCK_PTR
)
968 new_label
= block_label (new_bb
);
970 for (i
= 0; i
< n
; ++i
)
972 rtx old_ref
= ASM_OPERANDS_LABEL (tmp
, i
);
973 gcc_assert (GET_CODE (old_ref
) == LABEL_REF
);
974 if (XEXP (old_ref
, 0) == old_label
)
976 ASM_OPERANDS_LABEL (tmp
, i
)
977 = gen_rtx_LABEL_REF (Pmode
, new_label
);
978 --LABEL_NUSES (old_label
);
979 ++LABEL_NUSES (new_label
);
983 if (JUMP_LABEL (insn
) == old_label
)
985 JUMP_LABEL (insn
) = new_label
;
986 note
= find_reg_note (insn
, REG_LABEL_TARGET
, new_label
);
988 remove_note (insn
, note
);
992 note
= find_reg_note (insn
, REG_LABEL_TARGET
, old_label
);
994 remove_note (insn
, note
);
995 if (JUMP_LABEL (insn
) != new_label
996 && !find_reg_note (insn
, REG_LABEL_TARGET
, new_label
))
997 add_reg_note (insn
, REG_LABEL_TARGET
, new_label
);
999 while ((note
= find_reg_note (insn
, REG_LABEL_OPERAND
, old_label
))
1001 XEXP (note
, 0) = new_label
;
1005 /* ?? We may play the games with moving the named labels from
1006 one basic block to the other in case only one computed_jump is
1008 if (computed_jump_p (insn
)
1009 /* A return instruction can't be redirected. */
1010 || returnjump_p (insn
))
1013 if (!currently_expanding_to_rtl
|| JUMP_LABEL (insn
) == old_label
)
1015 /* If the insn doesn't go where we think, we're confused. */
1016 gcc_assert (JUMP_LABEL (insn
) == old_label
);
1018 /* If the substitution doesn't succeed, die. This can happen
1019 if the back end emitted unrecognizable instructions or if
1020 target is exit block on some arches. */
1021 if (!redirect_jump (insn
, block_label (new_bb
), 0))
1023 gcc_assert (new_bb
== EXIT_BLOCK_PTR
);
1032 /* Redirect edge representing branch of (un)conditional jump or tablejump,
1035 redirect_branch_edge (edge e
, basic_block target
)
1037 rtx old_label
= BB_HEAD (e
->dest
);
1038 basic_block src
= e
->src
;
1039 rtx insn
= BB_END (src
);
1041 /* We can only redirect non-fallthru edges of jump insn. */
1042 if (e
->flags
& EDGE_FALLTHRU
)
1044 else if (!JUMP_P (insn
) && !currently_expanding_to_rtl
)
1047 if (!currently_expanding_to_rtl
)
1049 if (!patch_jump_insn (insn
, old_label
, target
))
1053 /* When expanding this BB might actually contain multiple
1054 jumps (i.e. not yet split by find_many_sub_basic_blocks).
1055 Redirect all of those that match our label. */
1056 for (insn
= BB_HEAD (src
); insn
!= NEXT_INSN (BB_END (src
));
1057 insn
= NEXT_INSN (insn
))
1058 if (JUMP_P (insn
) && !patch_jump_insn (insn
, old_label
, target
))
1062 fprintf (dump_file
, "Edge %i->%i redirected to %i\n",
1063 e
->src
->index
, e
->dest
->index
, target
->index
);
1065 if (e
->dest
!= target
)
1066 e
= redirect_edge_succ_nodup (e
, target
);
1071 /* Attempt to change code to redirect edge E to TARGET. Don't do that on
1072 expense of adding new instructions or reordering basic blocks.
1074 Function can be also called with edge destination equivalent to the TARGET.
1075 Then it should try the simplifications and do nothing if none is possible.
1077 Return edge representing the branch if transformation succeeded. Return NULL
1079 We still return NULL in case E already destinated TARGET and we didn't
1080 managed to simplify instruction stream. */
1083 rtl_redirect_edge_and_branch (edge e
, basic_block target
)
1086 basic_block src
= e
->src
;
1088 if (e
->flags
& (EDGE_ABNORMAL_CALL
| EDGE_EH
))
1091 if (e
->dest
== target
)
1094 if ((ret
= try_redirect_by_replacing_jump (e
, target
, false)) != NULL
)
1096 df_set_bb_dirty (src
);
1100 ret
= redirect_branch_edge (e
, target
);
1104 df_set_bb_dirty (src
);
1108 /* Like force_nonfallthru below, but additionally performs redirection
1109 Used by redirect_edge_and_branch_force. */
1112 force_nonfallthru_and_redirect (edge e
, basic_block target
)
1114 basic_block jump_block
, new_bb
= NULL
, src
= e
->src
;
1117 int abnormal_edge_flags
= 0;
1120 /* In the case the last instruction is conditional jump to the next
1121 instruction, first redirect the jump itself and then continue
1122 by creating a basic block afterwards to redirect fallthru edge. */
1123 if (e
->src
!= ENTRY_BLOCK_PTR
&& e
->dest
!= EXIT_BLOCK_PTR
1124 && any_condjump_p (BB_END (e
->src
))
1125 && JUMP_LABEL (BB_END (e
->src
)) == BB_HEAD (e
->dest
))
1128 edge b
= unchecked_make_edge (e
->src
, target
, 0);
1131 redirected
= redirect_jump (BB_END (e
->src
), block_label (target
), 0);
1132 gcc_assert (redirected
);
1134 note
= find_reg_note (BB_END (e
->src
), REG_BR_PROB
, NULL_RTX
);
1137 int prob
= INTVAL (XEXP (note
, 0));
1139 b
->probability
= prob
;
1140 b
->count
= e
->count
* prob
/ REG_BR_PROB_BASE
;
1141 e
->probability
-= e
->probability
;
1142 e
->count
-= b
->count
;
1143 if (e
->probability
< 0)
1150 if (e
->flags
& EDGE_ABNORMAL
)
1152 /* Irritating special case - fallthru edge to the same block as abnormal
1154 We can't redirect abnormal edge, but we still can split the fallthru
1155 one and create separate abnormal edge to original destination.
1156 This allows bb-reorder to make such edge non-fallthru. */
1157 gcc_assert (e
->dest
== target
);
1158 abnormal_edge_flags
= e
->flags
& ~(EDGE_FALLTHRU
| EDGE_CAN_FALLTHRU
);
1159 e
->flags
&= EDGE_FALLTHRU
| EDGE_CAN_FALLTHRU
;
1163 gcc_assert (e
->flags
& EDGE_FALLTHRU
);
1164 if (e
->src
== ENTRY_BLOCK_PTR
)
1166 /* We can't redirect the entry block. Create an empty block
1167 at the start of the function which we use to add the new
1173 basic_block bb
= create_basic_block (BB_HEAD (e
->dest
), NULL
, ENTRY_BLOCK_PTR
);
1175 /* Change the existing edge's source to be the new block, and add
1176 a new edge from the entry block to the new block. */
1178 for (ei
= ei_start (ENTRY_BLOCK_PTR
->succs
); (tmp
= ei_safe_edge (ei
)); )
1182 VEC_unordered_remove (edge
, ENTRY_BLOCK_PTR
->succs
, ei
.index
);
1192 VEC_safe_push (edge
, gc
, bb
->succs
, e
);
1193 make_single_succ_edge (ENTRY_BLOCK_PTR
, bb
, EDGE_FALLTHRU
);
1197 if (EDGE_COUNT (e
->src
->succs
) >= 2 || abnormal_edge_flags
)
1199 /* Create the new structures. */
1201 /* If the old block ended with a tablejump, skip its table
1202 by searching forward from there. Otherwise start searching
1203 forward from the last instruction of the old block. */
1204 if (!tablejump_p (BB_END (e
->src
), NULL
, ¬e
))
1205 note
= BB_END (e
->src
);
1206 note
= NEXT_INSN (note
);
1208 jump_block
= create_basic_block (note
, NULL
, e
->src
);
1209 jump_block
->count
= e
->count
;
1210 jump_block
->frequency
= EDGE_FREQUENCY (e
);
1211 jump_block
->loop_depth
= target
->loop_depth
;
1213 /* Make sure new block ends up in correct hot/cold section. */
1215 BB_COPY_PARTITION (jump_block
, e
->src
);
1216 if (flag_reorder_blocks_and_partition
1217 && targetm
.have_named_sections
1218 && JUMP_P (BB_END (jump_block
))
1219 && !any_condjump_p (BB_END (jump_block
))
1220 && (EDGE_SUCC (jump_block
, 0)->flags
& EDGE_CROSSING
))
1221 add_reg_note (BB_END (jump_block
), REG_CROSSING_JUMP
, NULL_RTX
);
1224 new_edge
= make_edge (e
->src
, jump_block
, EDGE_FALLTHRU
);
1225 new_edge
->probability
= e
->probability
;
1226 new_edge
->count
= e
->count
;
1228 /* Redirect old edge. */
1229 redirect_edge_pred (e
, jump_block
);
1230 e
->probability
= REG_BR_PROB_BASE
;
1232 new_bb
= jump_block
;
1235 jump_block
= e
->src
;
1237 if (e
->goto_locus
&& e
->goto_block
== NULL
)
1238 loc
= e
->goto_locus
;
1241 e
->flags
&= ~EDGE_FALLTHRU
;
1242 if (target
== EXIT_BLOCK_PTR
)
1245 emit_jump_insn_after_setloc (gen_return (), BB_END (jump_block
), loc
);
1252 rtx label
= block_label (target
);
1253 emit_jump_insn_after_setloc (gen_jump (label
), BB_END (jump_block
), loc
);
1254 JUMP_LABEL (BB_END (jump_block
)) = label
;
1255 LABEL_NUSES (label
)++;
1258 emit_barrier_after (BB_END (jump_block
));
1259 redirect_edge_succ_nodup (e
, target
);
1261 if (abnormal_edge_flags
)
1262 make_edge (src
, target
, abnormal_edge_flags
);
1264 df_mark_solutions_dirty ();
1268 /* Edge E is assumed to be fallthru edge. Emit needed jump instruction
1269 (and possibly create new basic block) to make edge non-fallthru.
1270 Return newly created BB or NULL if none. */
1273 force_nonfallthru (edge e
)
1275 return force_nonfallthru_and_redirect (e
, e
->dest
);
1278 /* Redirect edge even at the expense of creating new jump insn or
1279 basic block. Return new basic block if created, NULL otherwise.
1280 Conversion must be possible. */
1283 rtl_redirect_edge_and_branch_force (edge e
, basic_block target
)
1285 if (redirect_edge_and_branch (e
, target
)
1286 || e
->dest
== target
)
1289 /* In case the edge redirection failed, try to force it to be non-fallthru
1290 and redirect newly created simplejump. */
1291 df_set_bb_dirty (e
->src
);
1292 return force_nonfallthru_and_redirect (e
, target
);
1295 /* The given edge should potentially be a fallthru edge. If that is in
1296 fact true, delete the jump and barriers that are in the way. */
1299 rtl_tidy_fallthru_edge (edge e
)
1302 basic_block b
= e
->src
, c
= b
->next_bb
;
1304 /* ??? In a late-running flow pass, other folks may have deleted basic
1305 blocks by nopping out blocks, leaving multiple BARRIERs between here
1306 and the target label. They ought to be chastised and fixed.
1308 We can also wind up with a sequence of undeletable labels between
1309 one block and the next.
1311 So search through a sequence of barriers, labels, and notes for
1312 the head of block C and assert that we really do fall through. */
1314 for (q
= NEXT_INSN (BB_END (b
)); q
!= BB_HEAD (c
); q
= NEXT_INSN (q
))
1318 /* Remove what will soon cease being the jump insn from the source block.
1319 If block B consisted only of this single jump, turn it into a deleted
1324 && (any_uncondjump_p (q
)
1325 || single_succ_p (b
)))
1328 /* If this was a conditional jump, we need to also delete
1329 the insn that set cc0. */
1330 if (any_condjump_p (q
) && only_sets_cc0_p (PREV_INSN (q
)))
1337 /* Selectively unlink the sequence. */
1338 if (q
!= PREV_INSN (BB_HEAD (c
)))
1339 delete_insn_chain (NEXT_INSN (q
), PREV_INSN (BB_HEAD (c
)), false);
1341 e
->flags
|= EDGE_FALLTHRU
;
1344 /* Should move basic block BB after basic block AFTER. NIY. */
1347 rtl_move_block_after (basic_block bb ATTRIBUTE_UNUSED
,
1348 basic_block after ATTRIBUTE_UNUSED
)
1353 /* Split a (typically critical) edge. Return the new block.
1354 The edge must not be abnormal.
1356 ??? The code generally expects to be called on critical edges.
1357 The case of a block ending in an unconditional jump to a
1358 block with multiple predecessors is not handled optimally. */
1361 rtl_split_edge (edge edge_in
)
1366 /* Abnormal edges cannot be split. */
1367 gcc_assert (!(edge_in
->flags
& EDGE_ABNORMAL
));
1369 /* We are going to place the new block in front of edge destination.
1370 Avoid existence of fallthru predecessors. */
1371 if ((edge_in
->flags
& EDGE_FALLTHRU
) == 0)
1373 edge e
= find_fallthru_edge (edge_in
->dest
->preds
);
1376 force_nonfallthru (e
);
1379 /* Create the basic block note. */
1380 if (edge_in
->dest
!= EXIT_BLOCK_PTR
)
1381 before
= BB_HEAD (edge_in
->dest
);
1385 /* If this is a fall through edge to the exit block, the blocks might be
1386 not adjacent, and the right place is the after the source. */
1387 if (edge_in
->flags
& EDGE_FALLTHRU
&& edge_in
->dest
== EXIT_BLOCK_PTR
)
1389 before
= NEXT_INSN (BB_END (edge_in
->src
));
1390 bb
= create_basic_block (before
, NULL
, edge_in
->src
);
1391 BB_COPY_PARTITION (bb
, edge_in
->src
);
1395 bb
= create_basic_block (before
, NULL
, edge_in
->dest
->prev_bb
);
1396 /* ??? Why not edge_in->dest->prev_bb here? */
1397 BB_COPY_PARTITION (bb
, edge_in
->dest
);
1400 make_single_succ_edge (bb
, edge_in
->dest
, EDGE_FALLTHRU
);
1402 /* For non-fallthru edges, we must adjust the predecessor's
1403 jump instruction to target our new block. */
1404 if ((edge_in
->flags
& EDGE_FALLTHRU
) == 0)
1406 edge redirected
= redirect_edge_and_branch (edge_in
, bb
);
1407 gcc_assert (redirected
);
1411 if (edge_in
->src
!= ENTRY_BLOCK_PTR
)
1413 /* For asm goto even splitting of fallthru edge might
1414 need insn patching, as other labels might point to the
1416 rtx last
= BB_END (edge_in
->src
);
1419 && edge_in
->dest
!= EXIT_BLOCK_PTR
1420 && extract_asm_operands (PATTERN (last
)) != NULL_RTX
1421 && patch_jump_insn (last
, before
, bb
))
1422 df_set_bb_dirty (edge_in
->src
);
1424 redirect_edge_succ (edge_in
, bb
);
1430 /* Queue instructions for insertion on an edge between two basic blocks.
1431 The new instructions and basic blocks (if any) will not appear in the
1432 CFG until commit_edge_insertions is called. */
1435 insert_insn_on_edge (rtx pattern
, edge e
)
1437 /* We cannot insert instructions on an abnormal critical edge.
1438 It will be easier to find the culprit if we die now. */
1439 gcc_assert (!((e
->flags
& EDGE_ABNORMAL
) && EDGE_CRITICAL_P (e
)));
1441 if (e
->insns
.r
== NULL_RTX
)
1444 push_to_sequence (e
->insns
.r
);
1446 emit_insn (pattern
);
1448 e
->insns
.r
= get_insns ();
1452 /* Update the CFG for the instructions queued on edge E. */
1455 commit_one_edge_insertion (edge e
)
1457 rtx before
= NULL_RTX
, after
= NULL_RTX
, insns
, tmp
, last
;
1458 basic_block bb
= NULL
;
1460 /* Pull the insns off the edge now since the edge might go away. */
1462 e
->insns
.r
= NULL_RTX
;
1464 if (!before
&& !after
)
1466 /* Figure out where to put these things. If the destination has
1467 one predecessor, insert there. Except for the exit block. */
1468 if (single_pred_p (e
->dest
) && e
->dest
!= EXIT_BLOCK_PTR
)
1472 /* Get the location correct wrt a code label, and "nice" wrt
1473 a basic block note, and before everything else. */
1476 tmp
= NEXT_INSN (tmp
);
1477 if (NOTE_INSN_BASIC_BLOCK_P (tmp
))
1478 tmp
= NEXT_INSN (tmp
);
1479 if (tmp
== BB_HEAD (bb
))
1482 after
= PREV_INSN (tmp
);
1484 after
= get_last_insn ();
1487 /* If the source has one successor and the edge is not abnormal,
1488 insert there. Except for the entry block. */
1489 else if ((e
->flags
& EDGE_ABNORMAL
) == 0
1490 && single_succ_p (e
->src
)
1491 && e
->src
!= ENTRY_BLOCK_PTR
)
1495 /* It is possible to have a non-simple jump here. Consider a target
1496 where some forms of unconditional jumps clobber a register. This
1497 happens on the fr30 for example.
1499 We know this block has a single successor, so we can just emit
1500 the queued insns before the jump. */
1501 if (JUMP_P (BB_END (bb
)))
1502 before
= BB_END (bb
);
1505 /* We'd better be fallthru, or we've lost track of
1507 gcc_assert (e
->flags
& EDGE_FALLTHRU
);
1509 after
= BB_END (bb
);
1512 /* Otherwise we must split the edge. */
1515 bb
= split_edge (e
);
1516 after
= BB_END (bb
);
1518 if (flag_reorder_blocks_and_partition
1519 && targetm
.have_named_sections
1520 && e
->src
!= ENTRY_BLOCK_PTR
1521 && BB_PARTITION (e
->src
) == BB_COLD_PARTITION
1522 && !(e
->flags
& EDGE_CROSSING
)
1524 && !any_condjump_p (after
)
1525 && (single_succ_edge (bb
)->flags
& EDGE_CROSSING
))
1526 add_reg_note (after
, REG_CROSSING_JUMP
, NULL_RTX
);
1530 /* Now that we've found the spot, do the insertion. */
1534 emit_insn_before_noloc (insns
, before
, bb
);
1535 last
= prev_nonnote_insn (before
);
1538 last
= emit_insn_after_noloc (insns
, after
, bb
);
1540 if (returnjump_p (last
))
1542 /* ??? Remove all outgoing edges from BB and add one for EXIT.
1543 This is not currently a problem because this only happens
1544 for the (single) epilogue, which already has a fallthru edge
1547 e
= single_succ_edge (bb
);
1548 gcc_assert (e
->dest
== EXIT_BLOCK_PTR
1549 && single_succ_p (bb
) && (e
->flags
& EDGE_FALLTHRU
));
1551 e
->flags
&= ~EDGE_FALLTHRU
;
1552 emit_barrier_after (last
);
1555 delete_insn (before
);
1558 gcc_assert (!JUMP_P (last
));
1560 /* Mark the basic block for find_many_sub_basic_blocks. */
1561 if (current_ir_type () != IR_RTL_CFGLAYOUT
)
1565 /* Update the CFG for all queued instructions. */
1568 commit_edge_insertions (void)
1572 bool changed
= false;
1574 #ifdef ENABLE_CHECKING
1575 verify_flow_info ();
1578 FOR_BB_BETWEEN (bb
, ENTRY_BLOCK_PTR
, EXIT_BLOCK_PTR
, next_bb
)
1583 FOR_EACH_EDGE (e
, ei
, bb
->succs
)
1587 commit_one_edge_insertion (e
);
1594 /* In the old rtl CFG API, it was OK to insert control flow on an
1595 edge, apparently? In cfglayout mode, this will *not* work, and
1596 the caller is responsible for making sure that control flow is
1597 valid at all times. */
1598 if (current_ir_type () == IR_RTL_CFGLAYOUT
)
1601 blocks
= sbitmap_alloc (last_basic_block
);
1602 sbitmap_zero (blocks
);
1606 SET_BIT (blocks
, bb
->index
);
1607 /* Check for forgotten bb->aux values before commit_edge_insertions
1609 gcc_assert (bb
->aux
== &bb
->aux
);
1612 find_many_sub_basic_blocks (blocks
);
1613 sbitmap_free (blocks
);
1617 /* Print out RTL-specific basic block information (live information
1618 at start and end). */
1621 rtl_dump_bb (basic_block bb
, FILE *outf
, int indent
, int flags ATTRIBUTE_UNUSED
)
1627 s_indent
= (char *) alloca ((size_t) indent
+ 1);
1628 memset (s_indent
, ' ', (size_t) indent
);
1629 s_indent
[indent
] = '\0';
1633 df_dump_top (bb
, outf
);
1637 for (insn
= BB_HEAD (bb
), last
= NEXT_INSN (BB_END (bb
)); insn
!= last
;
1638 insn
= NEXT_INSN (insn
))
1639 print_rtl_single (outf
, insn
);
1643 df_dump_bottom (bb
, outf
);
1649 /* Like print_rtl, but also print out live information for the start of each
1653 print_rtl_with_bb (FILE *outf
, const_rtx rtx_first
)
1657 fprintf (outf
, "(nil)\n");
1660 enum bb_state
{ NOT_IN_BB
, IN_ONE_BB
, IN_MULTIPLE_BB
};
1661 int max_uid
= get_max_uid ();
1662 basic_block
*start
= XCNEWVEC (basic_block
, max_uid
);
1663 basic_block
*end
= XCNEWVEC (basic_block
, max_uid
);
1664 enum bb_state
*in_bb_p
= XCNEWVEC (enum bb_state
, max_uid
);
1669 df_dump_start (outf
);
1671 FOR_EACH_BB_REVERSE (bb
)
1675 start
[INSN_UID (BB_HEAD (bb
))] = bb
;
1676 end
[INSN_UID (BB_END (bb
))] = bb
;
1677 for (x
= BB_HEAD (bb
); x
!= NULL_RTX
; x
= NEXT_INSN (x
))
1679 enum bb_state state
= IN_MULTIPLE_BB
;
1681 if (in_bb_p
[INSN_UID (x
)] == NOT_IN_BB
)
1683 in_bb_p
[INSN_UID (x
)] = state
;
1685 if (x
== BB_END (bb
))
1690 for (tmp_rtx
= rtx_first
; NULL
!= tmp_rtx
; tmp_rtx
= NEXT_INSN (tmp_rtx
))
1693 if ((bb
= start
[INSN_UID (tmp_rtx
)]) != NULL
)
1698 fprintf (outf
, ";; Start of basic block (");
1699 FOR_EACH_EDGE (e
, ei
, bb
->preds
)
1700 fprintf (outf
, " %d", e
->src
->index
);
1701 fprintf (outf
, ") -> %d\n", bb
->index
);
1705 df_dump_top (bb
, outf
);
1708 FOR_EACH_EDGE (e
, ei
, bb
->preds
)
1710 fputs (";; Pred edge ", outf
);
1711 dump_edge_info (outf
, e
, 0);
1716 if (in_bb_p
[INSN_UID (tmp_rtx
)] == NOT_IN_BB
1717 && !NOTE_P (tmp_rtx
)
1718 && !BARRIER_P (tmp_rtx
))
1719 fprintf (outf
, ";; Insn is not within a basic block\n");
1720 else if (in_bb_p
[INSN_UID (tmp_rtx
)] == IN_MULTIPLE_BB
)
1721 fprintf (outf
, ";; Insn is in multiple basic blocks\n");
1723 did_output
= print_rtl_single (outf
, tmp_rtx
);
1725 if ((bb
= end
[INSN_UID (tmp_rtx
)]) != NULL
)
1730 fprintf (outf
, ";; End of basic block %d -> (", bb
->index
);
1731 FOR_EACH_EDGE (e
, ei
, bb
->succs
)
1732 fprintf (outf
, " %d", e
->dest
->index
);
1733 fprintf (outf
, ")\n");
1737 df_dump_bottom (bb
, outf
);
1741 FOR_EACH_EDGE (e
, ei
, bb
->succs
)
1743 fputs (";; Succ edge ", outf
);
1744 dump_edge_info (outf
, e
, 1);
1757 if (crtl
->epilogue_delay_list
!= 0)
1759 fprintf (outf
, "\n;; Insns in epilogue delay list:\n\n");
1760 for (tmp_rtx
= crtl
->epilogue_delay_list
; tmp_rtx
!= 0;
1761 tmp_rtx
= XEXP (tmp_rtx
, 1))
1762 print_rtl_single (outf
, XEXP (tmp_rtx
, 0));
1767 update_br_prob_note (basic_block bb
)
1770 if (!JUMP_P (BB_END (bb
)))
1772 note
= find_reg_note (BB_END (bb
), REG_BR_PROB
, NULL_RTX
);
1773 if (!note
|| INTVAL (XEXP (note
, 0)) == BRANCH_EDGE (bb
)->probability
)
1775 XEXP (note
, 0) = GEN_INT (BRANCH_EDGE (bb
)->probability
);
1778 /* Get the last insn associated with block BB (that includes barriers and
1779 tablejumps after BB). */
1781 get_last_bb_insn (basic_block bb
)
1784 rtx end
= BB_END (bb
);
1786 /* Include any jump table following the basic block. */
1787 if (tablejump_p (end
, NULL
, &tmp
))
1790 /* Include any barriers that may follow the basic block. */
1791 tmp
= next_nonnote_insn_bb (end
);
1792 while (tmp
&& BARRIER_P (tmp
))
1795 tmp
= next_nonnote_insn_bb (end
);
1801 /* Verify the CFG and RTL consistency common for both underlying RTL and
1804 Currently it does following checks:
1806 - overlapping of basic blocks
1807 - insns with wrong BLOCK_FOR_INSN pointers
1808 - headers of basic blocks (the NOTE_INSN_BASIC_BLOCK note)
1809 - tails of basic blocks (ensure that boundary is necessary)
1810 - scans body of the basic block for JUMP_INSN, CODE_LABEL
1811 and NOTE_INSN_BASIC_BLOCK
1812 - verify that no fall_thru edge crosses hot/cold partition boundaries
1813 - verify that there are no pending RTL branch predictions
1815 In future it can be extended check a lot of other stuff as well
1816 (reachability of basic blocks, life information, etc. etc.). */
1819 rtl_verify_flow_info_1 (void)
1825 /* Check the general integrity of the basic blocks. */
1826 FOR_EACH_BB_REVERSE (bb
)
1830 if (!(bb
->flags
& BB_RTL
))
1832 error ("BB_RTL flag not set for block %d", bb
->index
);
1836 FOR_BB_INSNS (bb
, insn
)
1837 if (BLOCK_FOR_INSN (insn
) != bb
)
1839 error ("insn %d basic block pointer is %d, should be %d",
1841 BLOCK_FOR_INSN (insn
) ? BLOCK_FOR_INSN (insn
)->index
: 0,
1846 for (insn
= bb
->il
.rtl
->header
; insn
; insn
= NEXT_INSN (insn
))
1847 if (!BARRIER_P (insn
)
1848 && BLOCK_FOR_INSN (insn
) != NULL
)
1850 error ("insn %d in header of bb %d has non-NULL basic block",
1851 INSN_UID (insn
), bb
->index
);
1854 for (insn
= bb
->il
.rtl
->footer
; insn
; insn
= NEXT_INSN (insn
))
1855 if (!BARRIER_P (insn
)
1856 && BLOCK_FOR_INSN (insn
) != NULL
)
1858 error ("insn %d in footer of bb %d has non-NULL basic block",
1859 INSN_UID (insn
), bb
->index
);
1864 /* Now check the basic blocks (boundaries etc.) */
1865 FOR_EACH_BB_REVERSE (bb
)
1867 int n_fallthru
= 0, n_eh
= 0, n_call
= 0, n_abnormal
= 0, n_branch
= 0;
1868 edge e
, fallthru
= NULL
;
1872 if (JUMP_P (BB_END (bb
))
1873 && (note
= find_reg_note (BB_END (bb
), REG_BR_PROB
, NULL_RTX
))
1874 && EDGE_COUNT (bb
->succs
) >= 2
1875 && any_condjump_p (BB_END (bb
)))
1877 if (INTVAL (XEXP (note
, 0)) != BRANCH_EDGE (bb
)->probability
1878 && profile_status
!= PROFILE_ABSENT
)
1880 error ("verify_flow_info: REG_BR_PROB does not match cfg %wi %i",
1881 INTVAL (XEXP (note
, 0)), BRANCH_EDGE (bb
)->probability
);
1885 FOR_EACH_EDGE (e
, ei
, bb
->succs
)
1887 if (e
->flags
& EDGE_FALLTHRU
)
1889 n_fallthru
++, fallthru
= e
;
1890 if ((e
->flags
& EDGE_CROSSING
)
1891 || (BB_PARTITION (e
->src
) != BB_PARTITION (e
->dest
)
1892 && e
->src
!= ENTRY_BLOCK_PTR
1893 && e
->dest
!= EXIT_BLOCK_PTR
))
1895 error ("fallthru edge crosses section boundary (bb %i)",
1901 if ((e
->flags
& ~(EDGE_DFS_BACK
1903 | EDGE_IRREDUCIBLE_LOOP
1905 | EDGE_CROSSING
)) == 0)
1908 if (e
->flags
& EDGE_ABNORMAL_CALL
)
1911 if (e
->flags
& EDGE_EH
)
1913 else if (e
->flags
& EDGE_ABNORMAL
)
1917 if (n_eh
&& !find_reg_note (BB_END (bb
), REG_EH_REGION
, NULL_RTX
))
1919 error ("missing REG_EH_REGION note in the end of bb %i", bb
->index
);
1924 error ("too many eh edges %i", bb
->index
);
1928 && (!JUMP_P (BB_END (bb
))
1929 || (n_branch
> 1 && (any_uncondjump_p (BB_END (bb
))
1930 || any_condjump_p (BB_END (bb
))))))
1932 error ("too many outgoing branch edges from bb %i", bb
->index
);
1935 if (n_fallthru
&& any_uncondjump_p (BB_END (bb
)))
1937 error ("fallthru edge after unconditional jump %i", bb
->index
);
1940 if (n_branch
!= 1 && any_uncondjump_p (BB_END (bb
)))
1942 error ("wrong number of branch edges after unconditional jump %i",
1946 if (n_branch
!= 1 && any_condjump_p (BB_END (bb
))
1947 && JUMP_LABEL (BB_END (bb
)) != BB_HEAD (fallthru
->dest
))
1949 error ("wrong amount of branch edges after conditional jump %i",
1953 if (n_call
&& !CALL_P (BB_END (bb
)))
1955 error ("call edges for non-call insn in bb %i", bb
->index
);
1959 && (!CALL_P (BB_END (bb
)) && n_call
!= n_abnormal
)
1960 && (!JUMP_P (BB_END (bb
))
1961 || any_condjump_p (BB_END (bb
))
1962 || any_uncondjump_p (BB_END (bb
))))
1964 error ("abnormal edges for no purpose in bb %i", bb
->index
);
1968 for (x
= BB_HEAD (bb
); x
!= NEXT_INSN (BB_END (bb
)); x
= NEXT_INSN (x
))
1969 /* We may have a barrier inside a basic block before dead code
1970 elimination. There is no BLOCK_FOR_INSN field in a barrier. */
1971 if (!BARRIER_P (x
) && BLOCK_FOR_INSN (x
) != bb
)
1974 if (! BLOCK_FOR_INSN (x
))
1976 ("insn %d inside basic block %d but block_for_insn is NULL",
1977 INSN_UID (x
), bb
->index
);
1980 ("insn %d inside basic block %d but block_for_insn is %i",
1981 INSN_UID (x
), bb
->index
, BLOCK_FOR_INSN (x
)->index
);
1986 /* OK pointers are correct. Now check the header of basic
1987 block. It ought to contain optional CODE_LABEL followed
1988 by NOTE_BASIC_BLOCK. */
1992 if (BB_END (bb
) == x
)
1994 error ("NOTE_INSN_BASIC_BLOCK is missing for block %d",
2002 if (!NOTE_INSN_BASIC_BLOCK_P (x
) || NOTE_BASIC_BLOCK (x
) != bb
)
2004 error ("NOTE_INSN_BASIC_BLOCK is missing for block %d",
2009 if (BB_END (bb
) == x
)
2010 /* Do checks for empty blocks here. */
2013 for (x
= NEXT_INSN (x
); x
; x
= NEXT_INSN (x
))
2015 if (NOTE_INSN_BASIC_BLOCK_P (x
))
2017 error ("NOTE_INSN_BASIC_BLOCK %d in middle of basic block %d",
2018 INSN_UID (x
), bb
->index
);
2022 if (x
== BB_END (bb
))
2025 if (control_flow_insn_p (x
))
2027 error ("in basic block %d:", bb
->index
);
2028 fatal_insn ("flow control insn inside a basic block", x
);
2037 /* Verify the CFG and RTL consistency common for both underlying RTL and
2040 Currently it does following checks:
2041 - all checks of rtl_verify_flow_info_1
2042 - test head/end pointers
2043 - check that all insns are in the basic blocks
2044 (except the switch handling code, barriers and notes)
2045 - check that all returns are followed by barriers
2046 - check that all fallthru edge points to the adjacent blocks. */
2049 rtl_verify_flow_info (void)
2052 int err
= rtl_verify_flow_info_1 ();
2054 rtx last_head
= get_last_insn ();
2055 basic_block
*bb_info
;
2057 const rtx rtx_first
= get_insns ();
2058 basic_block last_bb_seen
= ENTRY_BLOCK_PTR
, curr_bb
= NULL
;
2059 const int max_uid
= get_max_uid ();
2061 bb_info
= XCNEWVEC (basic_block
, max_uid
);
2063 FOR_EACH_BB_REVERSE (bb
)
2066 rtx head
= BB_HEAD (bb
);
2067 rtx end
= BB_END (bb
);
2069 for (x
= last_head
; x
!= NULL_RTX
; x
= PREV_INSN (x
))
2071 /* Verify the end of the basic block is in the INSN chain. */
2075 /* And that the code outside of basic blocks has NULL bb field. */
2077 && BLOCK_FOR_INSN (x
) != NULL
)
2079 error ("insn %d outside of basic blocks has non-NULL bb field",
2087 error ("end insn %d for block %d not found in the insn stream",
2088 INSN_UID (end
), bb
->index
);
2092 /* Work backwards from the end to the head of the basic block
2093 to verify the head is in the RTL chain. */
2094 for (; x
!= NULL_RTX
; x
= PREV_INSN (x
))
2096 /* While walking over the insn chain, verify insns appear
2097 in only one basic block. */
2098 if (bb_info
[INSN_UID (x
)] != NULL
)
2100 error ("insn %d is in multiple basic blocks (%d and %d)",
2101 INSN_UID (x
), bb
->index
, bb_info
[INSN_UID (x
)]->index
);
2105 bb_info
[INSN_UID (x
)] = bb
;
2112 error ("head insn %d for block %d not found in the insn stream",
2113 INSN_UID (head
), bb
->index
);
2117 last_head
= PREV_INSN (x
);
2119 e
= find_fallthru_edge (bb
->succs
);
2124 /* Ensure existence of barrier in BB with no fallthru edges. */
2125 for (insn
= NEXT_INSN (BB_END (bb
)); ; insn
= NEXT_INSN (insn
))
2127 if (!insn
|| NOTE_INSN_BASIC_BLOCK_P (insn
))
2129 error ("missing barrier after block %i", bb
->index
);
2133 if (BARRIER_P (insn
))
2137 else if (e
->src
!= ENTRY_BLOCK_PTR
2138 && e
->dest
!= EXIT_BLOCK_PTR
)
2142 if (e
->src
->next_bb
!= e
->dest
)
2145 ("verify_flow_info: Incorrect blocks for fallthru %i->%i",
2146 e
->src
->index
, e
->dest
->index
);
2150 for (insn
= NEXT_INSN (BB_END (e
->src
)); insn
!= BB_HEAD (e
->dest
);
2151 insn
= NEXT_INSN (insn
))
2152 if (BARRIER_P (insn
) || INSN_P (insn
))
2154 error ("verify_flow_info: Incorrect fallthru %i->%i",
2155 e
->src
->index
, e
->dest
->index
);
2156 fatal_insn ("wrong insn in the fallthru edge", insn
);
2162 for (x
= last_head
; x
!= NULL_RTX
; x
= PREV_INSN (x
))
2164 /* Check that the code before the first basic block has NULL
2167 && BLOCK_FOR_INSN (x
) != NULL
)
2169 error ("insn %d outside of basic blocks has non-NULL bb field",
2177 last_bb_seen
= ENTRY_BLOCK_PTR
;
2179 for (x
= rtx_first
; x
; x
= NEXT_INSN (x
))
2181 if (NOTE_INSN_BASIC_BLOCK_P (x
))
2183 bb
= NOTE_BASIC_BLOCK (x
);
2186 if (bb
!= last_bb_seen
->next_bb
)
2187 internal_error ("basic blocks not laid down consecutively");
2189 curr_bb
= last_bb_seen
= bb
;
2194 switch (GET_CODE (x
))
2201 /* An addr_vec is placed outside any basic block. */
2203 && JUMP_TABLE_DATA_P (NEXT_INSN (x
)))
2206 /* But in any case, non-deletable labels can appear anywhere. */
2210 fatal_insn ("insn outside basic block", x
);
2215 && returnjump_p (x
) && ! condjump_p (x
)
2216 && ! (next_nonnote_insn (x
) && BARRIER_P (next_nonnote_insn (x
))))
2217 fatal_insn ("return not followed by barrier", x
);
2218 if (curr_bb
&& x
== BB_END (curr_bb
))
2222 if (num_bb_notes
!= n_basic_blocks
- NUM_FIXED_BLOCKS
)
2224 ("number of bb notes in insn chain (%d) != n_basic_blocks (%d)",
2225 num_bb_notes
, n_basic_blocks
);
2230 /* Assume that the preceding pass has possibly eliminated jump instructions
2231 or converted the unconditional jumps. Eliminate the edges from CFG.
2232 Return true if any edges are eliminated. */
2235 purge_dead_edges (basic_block bb
)
2238 rtx insn
= BB_END (bb
), note
;
2239 bool purged
= false;
2243 if (DEBUG_INSN_P (insn
) && insn
!= BB_HEAD (bb
))
2245 insn
= PREV_INSN (insn
);
2246 while ((DEBUG_INSN_P (insn
) || NOTE_P (insn
)) && insn
!= BB_HEAD (bb
));
2248 /* If this instruction cannot trap, remove REG_EH_REGION notes. */
2249 if (NONJUMP_INSN_P (insn
)
2250 && (note
= find_reg_note (insn
, REG_EH_REGION
, NULL
)))
2254 if (! may_trap_p (PATTERN (insn
))
2255 || ((eqnote
= find_reg_equal_equiv_note (insn
))
2256 && ! may_trap_p (XEXP (eqnote
, 0))))
2257 remove_note (insn
, note
);
2260 /* Cleanup abnormal edges caused by exceptions or non-local gotos. */
2261 for (ei
= ei_start (bb
->succs
); (e
= ei_safe_edge (ei
)); )
2263 bool remove
= false;
2265 /* There are three types of edges we need to handle correctly here: EH
2266 edges, abnormal call EH edges, and abnormal call non-EH edges. The
2267 latter can appear when nonlocal gotos are used. */
2268 if (e
->flags
& EDGE_ABNORMAL_CALL
)
2272 else if (can_nonlocal_goto (insn
))
2274 else if ((e
->flags
& EDGE_EH
) && can_throw_internal (insn
))
2279 else if (e
->flags
& EDGE_EH
)
2280 remove
= !can_throw_internal (insn
);
2285 df_set_bb_dirty (bb
);
2298 /* We do care only about conditional jumps and simplejumps. */
2299 if (!any_condjump_p (insn
)
2300 && !returnjump_p (insn
)
2301 && !simplejump_p (insn
))
2304 /* Branch probability/prediction notes are defined only for
2305 condjumps. We've possibly turned condjump into simplejump. */
2306 if (simplejump_p (insn
))
2308 note
= find_reg_note (insn
, REG_BR_PROB
, NULL
);
2310 remove_note (insn
, note
);
2311 while ((note
= find_reg_note (insn
, REG_BR_PRED
, NULL
)))
2312 remove_note (insn
, note
);
2315 for (ei
= ei_start (bb
->succs
); (e
= ei_safe_edge (ei
)); )
2317 /* Avoid abnormal flags to leak from computed jumps turned
2318 into simplejumps. */
2320 e
->flags
&= ~EDGE_ABNORMAL
;
2322 /* See if this edge is one we should keep. */
2323 if ((e
->flags
& EDGE_FALLTHRU
) && any_condjump_p (insn
))
2324 /* A conditional jump can fall through into the next
2325 block, so we should keep the edge. */
2330 else if (e
->dest
!= EXIT_BLOCK_PTR
2331 && BB_HEAD (e
->dest
) == JUMP_LABEL (insn
))
2332 /* If the destination block is the target of the jump,
2338 else if (e
->dest
== EXIT_BLOCK_PTR
&& returnjump_p (insn
))
2339 /* If the destination block is the exit block, and this
2340 instruction is a return, then keep the edge. */
2345 else if ((e
->flags
& EDGE_EH
) && can_throw_internal (insn
))
2346 /* Keep the edges that correspond to exceptions thrown by
2347 this instruction and rematerialize the EDGE_ABNORMAL
2348 flag we just cleared above. */
2350 e
->flags
|= EDGE_ABNORMAL
;
2355 /* We do not need this edge. */
2356 df_set_bb_dirty (bb
);
2361 if (EDGE_COUNT (bb
->succs
) == 0 || !purged
)
2365 fprintf (dump_file
, "Purged edges from bb %i\n", bb
->index
);
2370 /* Redistribute probabilities. */
2371 if (single_succ_p (bb
))
2373 single_succ_edge (bb
)->probability
= REG_BR_PROB_BASE
;
2374 single_succ_edge (bb
)->count
= bb
->count
;
2378 note
= find_reg_note (insn
, REG_BR_PROB
, NULL
);
2382 b
= BRANCH_EDGE (bb
);
2383 f
= FALLTHRU_EDGE (bb
);
2384 b
->probability
= INTVAL (XEXP (note
, 0));
2385 f
->probability
= REG_BR_PROB_BASE
- b
->probability
;
2386 b
->count
= bb
->count
* b
->probability
/ REG_BR_PROB_BASE
;
2387 f
->count
= bb
->count
* f
->probability
/ REG_BR_PROB_BASE
;
2392 else if (CALL_P (insn
) && SIBLING_CALL_P (insn
))
2394 /* First, there should not be any EH or ABCALL edges resulting
2395 from non-local gotos and the like. If there were, we shouldn't
2396 have created the sibcall in the first place. Second, there
2397 should of course never have been a fallthru edge. */
2398 gcc_assert (single_succ_p (bb
));
2399 gcc_assert (single_succ_edge (bb
)->flags
2400 == (EDGE_SIBCALL
| EDGE_ABNORMAL
));
2405 /* If we don't see a jump insn, we don't know exactly why the block would
2406 have been broken at this point. Look for a simple, non-fallthru edge,
2407 as these are only created by conditional branches. If we find such an
2408 edge we know that there used to be a jump here and can then safely
2409 remove all non-fallthru edges. */
2411 FOR_EACH_EDGE (e
, ei
, bb
->succs
)
2412 if (! (e
->flags
& (EDGE_COMPLEX
| EDGE_FALLTHRU
)))
2421 /* Remove all but the fake and fallthru edges. The fake edge may be
2422 the only successor for this block in the case of noreturn
2424 for (ei
= ei_start (bb
->succs
); (e
= ei_safe_edge (ei
)); )
2426 if (!(e
->flags
& (EDGE_FALLTHRU
| EDGE_FAKE
)))
2428 df_set_bb_dirty (bb
);
2436 gcc_assert (single_succ_p (bb
));
2438 single_succ_edge (bb
)->probability
= REG_BR_PROB_BASE
;
2439 single_succ_edge (bb
)->count
= bb
->count
;
2442 fprintf (dump_file
, "Purged non-fallthru edges from bb %i\n",
2447 /* Search all basic blocks for potentially dead edges and purge them. Return
2448 true if some edge has been eliminated. */
2451 purge_all_dead_edges (void)
2458 bool purged_here
= purge_dead_edges (bb
);
2460 purged
|= purged_here
;
2466 /* Same as split_block but update cfg_layout structures. */
2469 cfg_layout_split_block (basic_block bb
, void *insnp
)
2471 rtx insn
= (rtx
) insnp
;
2472 basic_block new_bb
= rtl_split_block (bb
, insn
);
2474 new_bb
->il
.rtl
->footer
= bb
->il
.rtl
->footer
;
2475 bb
->il
.rtl
->footer
= NULL
;
2480 /* Redirect Edge to DEST. */
2482 cfg_layout_redirect_edge_and_branch (edge e
, basic_block dest
)
2484 basic_block src
= e
->src
;
2487 if (e
->flags
& (EDGE_ABNORMAL_CALL
| EDGE_EH
))
2490 if (e
->dest
== dest
)
2493 if (e
->src
!= ENTRY_BLOCK_PTR
2494 && (ret
= try_redirect_by_replacing_jump (e
, dest
, true)))
2496 df_set_bb_dirty (src
);
2500 if (e
->src
== ENTRY_BLOCK_PTR
2501 && (e
->flags
& EDGE_FALLTHRU
) && !(e
->flags
& EDGE_COMPLEX
))
2504 fprintf (dump_file
, "Redirecting entry edge from bb %i to %i\n",
2505 e
->src
->index
, dest
->index
);
2507 df_set_bb_dirty (e
->src
);
2508 redirect_edge_succ (e
, dest
);
2512 /* Redirect_edge_and_branch may decide to turn branch into fallthru edge
2513 in the case the basic block appears to be in sequence. Avoid this
2516 if (e
->flags
& EDGE_FALLTHRU
)
2518 /* Redirect any branch edges unified with the fallthru one. */
2519 if (JUMP_P (BB_END (src
))
2520 && label_is_jump_target_p (BB_HEAD (e
->dest
),
2526 fprintf (dump_file
, "Fallthru edge unified with branch "
2527 "%i->%i redirected to %i\n",
2528 e
->src
->index
, e
->dest
->index
, dest
->index
);
2529 e
->flags
&= ~EDGE_FALLTHRU
;
2530 redirected
= redirect_branch_edge (e
, dest
);
2531 gcc_assert (redirected
);
2532 e
->flags
|= EDGE_FALLTHRU
;
2533 df_set_bb_dirty (e
->src
);
2536 /* In case we are redirecting fallthru edge to the branch edge
2537 of conditional jump, remove it. */
2538 if (EDGE_COUNT (src
->succs
) == 2)
2540 /* Find the edge that is different from E. */
2541 edge s
= EDGE_SUCC (src
, EDGE_SUCC (src
, 0) == e
);
2544 && any_condjump_p (BB_END (src
))
2545 && onlyjump_p (BB_END (src
)))
2546 delete_insn (BB_END (src
));
2548 ret
= redirect_edge_succ_nodup (e
, dest
);
2550 fprintf (dump_file
, "Fallthru edge %i->%i redirected to %i\n",
2551 e
->src
->index
, e
->dest
->index
, dest
->index
);
2554 ret
= redirect_branch_edge (e
, dest
);
2556 /* We don't want simplejumps in the insn stream during cfglayout. */
2557 gcc_assert (!simplejump_p (BB_END (src
)));
2559 df_set_bb_dirty (src
);
2563 /* Simple wrapper as we always can redirect fallthru edges. */
2565 cfg_layout_redirect_edge_and_branch_force (edge e
, basic_block dest
)
2567 edge redirected
= cfg_layout_redirect_edge_and_branch (e
, dest
);
2569 gcc_assert (redirected
);
2573 /* Same as delete_basic_block but update cfg_layout structures. */
2576 cfg_layout_delete_block (basic_block bb
)
2578 rtx insn
, next
, prev
= PREV_INSN (BB_HEAD (bb
)), *to
, remaints
;
2580 if (bb
->il
.rtl
->header
)
2582 next
= BB_HEAD (bb
);
2584 NEXT_INSN (prev
) = bb
->il
.rtl
->header
;
2586 set_first_insn (bb
->il
.rtl
->header
);
2587 PREV_INSN (bb
->il
.rtl
->header
) = prev
;
2588 insn
= bb
->il
.rtl
->header
;
2589 while (NEXT_INSN (insn
))
2590 insn
= NEXT_INSN (insn
);
2591 NEXT_INSN (insn
) = next
;
2592 PREV_INSN (next
) = insn
;
2594 next
= NEXT_INSN (BB_END (bb
));
2595 if (bb
->il
.rtl
->footer
)
2597 insn
= bb
->il
.rtl
->footer
;
2600 if (BARRIER_P (insn
))
2602 if (PREV_INSN (insn
))
2603 NEXT_INSN (PREV_INSN (insn
)) = NEXT_INSN (insn
);
2605 bb
->il
.rtl
->footer
= NEXT_INSN (insn
);
2606 if (NEXT_INSN (insn
))
2607 PREV_INSN (NEXT_INSN (insn
)) = PREV_INSN (insn
);
2611 insn
= NEXT_INSN (insn
);
2613 if (bb
->il
.rtl
->footer
)
2616 NEXT_INSN (insn
) = bb
->il
.rtl
->footer
;
2617 PREV_INSN (bb
->il
.rtl
->footer
) = insn
;
2618 while (NEXT_INSN (insn
))
2619 insn
= NEXT_INSN (insn
);
2620 NEXT_INSN (insn
) = next
;
2622 PREV_INSN (next
) = insn
;
2624 set_last_insn (insn
);
2627 if (bb
->next_bb
!= EXIT_BLOCK_PTR
)
2628 to
= &bb
->next_bb
->il
.rtl
->header
;
2630 to
= &cfg_layout_function_footer
;
2632 rtl_delete_block (bb
);
2635 prev
= NEXT_INSN (prev
);
2637 prev
= get_insns ();
2639 next
= PREV_INSN (next
);
2641 next
= get_last_insn ();
2643 if (next
&& NEXT_INSN (next
) != prev
)
2645 remaints
= unlink_insn_chain (prev
, next
);
2647 while (NEXT_INSN (insn
))
2648 insn
= NEXT_INSN (insn
);
2649 NEXT_INSN (insn
) = *to
;
2651 PREV_INSN (*to
) = insn
;
2656 /* Return true when blocks A and B can be safely merged. */
2659 cfg_layout_can_merge_blocks_p (basic_block a
, basic_block b
)
2661 /* If we are partitioning hot/cold basic blocks, we don't want to
2662 mess up unconditional or indirect jumps that cross between hot
2665 Basic block partitioning may result in some jumps that appear to
2666 be optimizable (or blocks that appear to be mergeable), but which really
2667 must be left untouched (they are required to make it safely across
2668 partition boundaries). See the comments at the top of
2669 bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */
2671 if (BB_PARTITION (a
) != BB_PARTITION (b
))
2674 /* There must be exactly one edge in between the blocks. */
2675 return (single_succ_p (a
)
2676 && single_succ (a
) == b
2677 && single_pred_p (b
) == 1
2679 /* Must be simple edge. */
2680 && !(single_succ_edge (a
)->flags
& EDGE_COMPLEX
)
2681 && a
!= ENTRY_BLOCK_PTR
&& b
!= EXIT_BLOCK_PTR
2682 /* If the jump insn has side effects, we can't kill the edge.
2683 When not optimizing, try_redirect_by_replacing_jump will
2684 not allow us to redirect an edge by replacing a table jump. */
2685 && (!JUMP_P (BB_END (a
))
2686 || ((!optimize
|| reload_completed
)
2687 ? simplejump_p (BB_END (a
)) : onlyjump_p (BB_END (a
)))));
2690 /* Merge block A and B. The blocks must be mergeable. */
2693 cfg_layout_merge_blocks (basic_block a
, basic_block b
)
2695 #ifdef ENABLE_CHECKING
2696 gcc_assert (cfg_layout_can_merge_blocks_p (a
, b
));
2700 fprintf (dump_file
, "merging block %d into block %d\n", b
->index
, a
->index
);
2702 /* If there was a CODE_LABEL beginning B, delete it. */
2703 if (LABEL_P (BB_HEAD (b
)))
2705 delete_insn (BB_HEAD (b
));
2708 /* We should have fallthru edge in a, or we can do dummy redirection to get
2710 if (JUMP_P (BB_END (a
)))
2711 try_redirect_by_replacing_jump (EDGE_SUCC (a
, 0), b
, true);
2712 gcc_assert (!JUMP_P (BB_END (a
)));
2714 /* When not optimizing and the edge is the only place in RTL which holds
2715 some unique locus, emit a nop with that locus in between. */
2716 if (!optimize
&& EDGE_SUCC (a
, 0)->goto_locus
)
2718 rtx insn
= BB_END (a
), end
= PREV_INSN (BB_HEAD (a
));
2719 int goto_locus
= EDGE_SUCC (a
, 0)->goto_locus
;
2721 while (insn
!= end
&& (!INSN_P (insn
) || INSN_LOCATOR (insn
) == 0))
2722 insn
= PREV_INSN (insn
);
2723 if (insn
!= end
&& locator_eq (INSN_LOCATOR (insn
), goto_locus
))
2728 end
= NEXT_INSN (BB_END (b
));
2729 while (insn
!= end
&& !INSN_P (insn
))
2730 insn
= NEXT_INSN (insn
);
2731 if (insn
!= end
&& INSN_LOCATOR (insn
) != 0
2732 && locator_eq (INSN_LOCATOR (insn
), goto_locus
))
2737 BB_END (a
) = emit_insn_after_noloc (gen_nop (), BB_END (a
), a
);
2738 INSN_LOCATOR (BB_END (a
)) = goto_locus
;
2742 /* Possible line number notes should appear in between. */
2743 if (b
->il
.rtl
->header
)
2745 rtx first
= BB_END (a
), last
;
2747 last
= emit_insn_after_noloc (b
->il
.rtl
->header
, BB_END (a
), a
);
2748 delete_insn_chain (NEXT_INSN (first
), last
, false);
2749 b
->il
.rtl
->header
= NULL
;
2752 /* In the case basic blocks are not adjacent, move them around. */
2753 if (NEXT_INSN (BB_END (a
)) != BB_HEAD (b
))
2755 rtx first
= unlink_insn_chain (BB_HEAD (b
), BB_END (b
));
2757 emit_insn_after_noloc (first
, BB_END (a
), a
);
2758 /* Skip possible DELETED_LABEL insn. */
2759 if (!NOTE_INSN_BASIC_BLOCK_P (first
))
2760 first
= NEXT_INSN (first
);
2761 gcc_assert (NOTE_INSN_BASIC_BLOCK_P (first
));
2764 /* emit_insn_after_noloc doesn't call df_insn_change_bb.
2765 We need to explicitly call. */
2766 update_bb_for_insn_chain (NEXT_INSN (first
),
2770 delete_insn (first
);
2772 /* Otherwise just re-associate the instructions. */
2777 update_bb_for_insn_chain (BB_HEAD (b
), BB_END (b
), a
);
2780 /* Skip possible DELETED_LABEL insn. */
2781 if (!NOTE_INSN_BASIC_BLOCK_P (insn
))
2782 insn
= NEXT_INSN (insn
);
2783 gcc_assert (NOTE_INSN_BASIC_BLOCK_P (insn
));
2785 BB_END (a
) = BB_END (b
);
2789 df_bb_delete (b
->index
);
2791 /* Possible tablejumps and barriers should appear after the block. */
2792 if (b
->il
.rtl
->footer
)
2794 if (!a
->il
.rtl
->footer
)
2795 a
->il
.rtl
->footer
= b
->il
.rtl
->footer
;
2798 rtx last
= a
->il
.rtl
->footer
;
2800 while (NEXT_INSN (last
))
2801 last
= NEXT_INSN (last
);
2802 NEXT_INSN (last
) = b
->il
.rtl
->footer
;
2803 PREV_INSN (b
->il
.rtl
->footer
) = last
;
2805 b
->il
.rtl
->footer
= NULL
;
2809 fprintf (dump_file
, "Merged blocks %d and %d.\n",
2810 a
->index
, b
->index
);
2816 cfg_layout_split_edge (edge e
)
2818 basic_block new_bb
=
2819 create_basic_block (e
->src
!= ENTRY_BLOCK_PTR
2820 ? NEXT_INSN (BB_END (e
->src
)) : get_insns (),
2823 if (e
->dest
== EXIT_BLOCK_PTR
)
2824 BB_COPY_PARTITION (new_bb
, e
->src
);
2826 BB_COPY_PARTITION (new_bb
, e
->dest
);
2827 make_edge (new_bb
, e
->dest
, EDGE_FALLTHRU
);
2828 redirect_edge_and_branch_force (e
, new_bb
);
2833 /* Do postprocessing after making a forwarder block joined by edge FALLTHRU. */
2836 rtl_make_forwarder_block (edge fallthru ATTRIBUTE_UNUSED
)
2840 /* Return 1 if BB ends with a call, possibly followed by some
2841 instructions that must stay with the call, 0 otherwise. */
2844 rtl_block_ends_with_call_p (basic_block bb
)
2846 rtx insn
= BB_END (bb
);
2848 while (!CALL_P (insn
)
2849 && insn
!= BB_HEAD (bb
)
2850 && (keep_with_call_p (insn
)
2852 || DEBUG_INSN_P (insn
)))
2853 insn
= PREV_INSN (insn
);
2854 return (CALL_P (insn
));
2857 /* Return 1 if BB ends with a conditional branch, 0 otherwise. */
2860 rtl_block_ends_with_condjump_p (const_basic_block bb
)
2862 return any_condjump_p (BB_END (bb
));
2865 /* Return true if we need to add fake edge to exit.
2866 Helper function for rtl_flow_call_edges_add. */
2869 need_fake_edge_p (const_rtx insn
)
2875 && !SIBLING_CALL_P (insn
)
2876 && !find_reg_note (insn
, REG_NORETURN
, NULL
)
2877 && !(RTL_CONST_OR_PURE_CALL_P (insn
))))
2880 return ((GET_CODE (PATTERN (insn
)) == ASM_OPERANDS
2881 && MEM_VOLATILE_P (PATTERN (insn
)))
2882 || (GET_CODE (PATTERN (insn
)) == PARALLEL
2883 && asm_noperands (insn
) != -1
2884 && MEM_VOLATILE_P (XVECEXP (PATTERN (insn
), 0, 0)))
2885 || GET_CODE (PATTERN (insn
)) == ASM_INPUT
);
2888 /* Add fake edges to the function exit for any non constant and non noreturn
2889 calls, volatile inline assembly in the bitmap of blocks specified by
2890 BLOCKS or to the whole CFG if BLOCKS is zero. Return the number of blocks
2893 The goal is to expose cases in which entering a basic block does not imply
2894 that all subsequent instructions must be executed. */
2897 rtl_flow_call_edges_add (sbitmap blocks
)
2900 int blocks_split
= 0;
2901 int last_bb
= last_basic_block
;
2902 bool check_last_block
= false;
2904 if (n_basic_blocks
== NUM_FIXED_BLOCKS
)
2908 check_last_block
= true;
2910 check_last_block
= TEST_BIT (blocks
, EXIT_BLOCK_PTR
->prev_bb
->index
);
2912 /* In the last basic block, before epilogue generation, there will be
2913 a fallthru edge to EXIT. Special care is required if the last insn
2914 of the last basic block is a call because make_edge folds duplicate
2915 edges, which would result in the fallthru edge also being marked
2916 fake, which would result in the fallthru edge being removed by
2917 remove_fake_edges, which would result in an invalid CFG.
2919 Moreover, we can't elide the outgoing fake edge, since the block
2920 profiler needs to take this into account in order to solve the minimal
2921 spanning tree in the case that the call doesn't return.
2923 Handle this by adding a dummy instruction in a new last basic block. */
2924 if (check_last_block
)
2926 basic_block bb
= EXIT_BLOCK_PTR
->prev_bb
;
2927 rtx insn
= BB_END (bb
);
2929 /* Back up past insns that must be kept in the same block as a call. */
2930 while (insn
!= BB_HEAD (bb
)
2931 && keep_with_call_p (insn
))
2932 insn
= PREV_INSN (insn
);
2934 if (need_fake_edge_p (insn
))
2938 e
= find_edge (bb
, EXIT_BLOCK_PTR
);
2941 insert_insn_on_edge (gen_use (const0_rtx
), e
);
2942 commit_edge_insertions ();
2947 /* Now add fake edges to the function exit for any non constant
2948 calls since there is no way that we can determine if they will
2951 for (i
= NUM_FIXED_BLOCKS
; i
< last_bb
; i
++)
2953 basic_block bb
= BASIC_BLOCK (i
);
2960 if (blocks
&& !TEST_BIT (blocks
, i
))
2963 for (insn
= BB_END (bb
); ; insn
= prev_insn
)
2965 prev_insn
= PREV_INSN (insn
);
2966 if (need_fake_edge_p (insn
))
2969 rtx split_at_insn
= insn
;
2971 /* Don't split the block between a call and an insn that should
2972 remain in the same block as the call. */
2974 while (split_at_insn
!= BB_END (bb
)
2975 && keep_with_call_p (NEXT_INSN (split_at_insn
)))
2976 split_at_insn
= NEXT_INSN (split_at_insn
);
2978 /* The handling above of the final block before the epilogue
2979 should be enough to verify that there is no edge to the exit
2980 block in CFG already. Calling make_edge in such case would
2981 cause us to mark that edge as fake and remove it later. */
2983 #ifdef ENABLE_CHECKING
2984 if (split_at_insn
== BB_END (bb
))
2986 e
= find_edge (bb
, EXIT_BLOCK_PTR
);
2987 gcc_assert (e
== NULL
);
2991 /* Note that the following may create a new basic block
2992 and renumber the existing basic blocks. */
2993 if (split_at_insn
!= BB_END (bb
))
2995 e
= split_block (bb
, split_at_insn
);
3000 make_edge (bb
, EXIT_BLOCK_PTR
, EDGE_FAKE
);
3003 if (insn
== BB_HEAD (bb
))
3009 verify_flow_info ();
3011 return blocks_split
;
3014 /* Add COMP_RTX as a condition at end of COND_BB. FIRST_HEAD is
3015 the conditional branch target, SECOND_HEAD should be the fall-thru
3016 there is no need to handle this here the loop versioning code handles
3017 this. the reason for SECON_HEAD is that it is needed for condition
3018 in trees, and this should be of the same type since it is a hook. */
3020 rtl_lv_add_condition_to_bb (basic_block first_head
,
3021 basic_block second_head ATTRIBUTE_UNUSED
,
3022 basic_block cond_bb
, void *comp_rtx
)
3024 rtx label
, seq
, jump
;
3025 rtx op0
= XEXP ((rtx
)comp_rtx
, 0);
3026 rtx op1
= XEXP ((rtx
)comp_rtx
, 1);
3027 enum rtx_code comp
= GET_CODE ((rtx
)comp_rtx
);
3028 enum machine_mode mode
;
3031 label
= block_label (first_head
);
3032 mode
= GET_MODE (op0
);
3033 if (mode
== VOIDmode
)
3034 mode
= GET_MODE (op1
);
3037 op0
= force_operand (op0
, NULL_RTX
);
3038 op1
= force_operand (op1
, NULL_RTX
);
3039 do_compare_rtx_and_jump (op0
, op1
, comp
, 0,
3040 mode
, NULL_RTX
, NULL_RTX
, label
, -1);
3041 jump
= get_last_insn ();
3042 JUMP_LABEL (jump
) = label
;
3043 LABEL_NUSES (label
)++;
3047 /* Add the new cond , in the new head. */
3048 emit_insn_after(seq
, BB_END(cond_bb
));
3052 /* Given a block B with unconditional branch at its end, get the
3053 store the return the branch edge and the fall-thru edge in
3054 BRANCH_EDGE and FALLTHRU_EDGE respectively. */
3056 rtl_extract_cond_bb_edges (basic_block b
, edge
*branch_edge
,
3057 edge
*fallthru_edge
)
3059 edge e
= EDGE_SUCC (b
, 0);
3061 if (e
->flags
& EDGE_FALLTHRU
)
3064 *branch_edge
= EDGE_SUCC (b
, 1);
3069 *fallthru_edge
= EDGE_SUCC (b
, 1);
3074 init_rtl_bb_info (basic_block bb
)
3076 gcc_assert (!bb
->il
.rtl
);
3077 bb
->il
.rtl
= ggc_alloc_cleared_rtl_bb_info ();
3081 /* Add EXPR to the end of basic block BB. */
3084 insert_insn_end_bb_new (rtx pat
, basic_block bb
)
3086 rtx insn
= BB_END (bb
);
3090 while (NEXT_INSN (pat_end
) != NULL_RTX
)
3091 pat_end
= NEXT_INSN (pat_end
);
3093 /* If the last insn is a jump, insert EXPR in front [taking care to
3094 handle cc0, etc. properly]. Similarly we need to care trapping
3095 instructions in presence of non-call exceptions. */
3098 || (NONJUMP_INSN_P (insn
)
3099 && (!single_succ_p (bb
)
3100 || single_succ_edge (bb
)->flags
& EDGE_ABNORMAL
)))
3105 /* If this is a jump table, then we can't insert stuff here. Since
3106 we know the previous real insn must be the tablejump, we insert
3107 the new instruction just before the tablejump. */
3108 if (GET_CODE (PATTERN (insn
)) == ADDR_VEC
3109 || GET_CODE (PATTERN (insn
)) == ADDR_DIFF_VEC
)
3110 insn
= prev_real_insn (insn
);
3113 /* FIXME: 'twould be nice to call prev_cc0_setter here but it aborts
3114 if cc0 isn't set. */
3115 note
= find_reg_note (insn
, REG_CC_SETTER
, NULL_RTX
);
3117 insn
= XEXP (note
, 0);
3120 rtx maybe_cc0_setter
= prev_nonnote_insn (insn
);
3121 if (maybe_cc0_setter
3122 && INSN_P (maybe_cc0_setter
)
3123 && sets_cc0_p (PATTERN (maybe_cc0_setter
)))
3124 insn
= maybe_cc0_setter
;
3127 /* FIXME: What if something in cc0/jump uses value set in new
3129 new_insn
= emit_insn_before_noloc (pat
, insn
, bb
);
3132 /* Likewise if the last insn is a call, as will happen in the presence
3133 of exception handling. */
3134 else if (CALL_P (insn
)
3135 && (!single_succ_p (bb
)
3136 || single_succ_edge (bb
)->flags
& EDGE_ABNORMAL
))
3138 /* Keeping in mind targets with small register classes and parameters
3139 in registers, we search backward and place the instructions before
3140 the first parameter is loaded. Do this for everyone for consistency
3141 and a presumption that we'll get better code elsewhere as well. */
3143 /* Since different machines initialize their parameter registers
3144 in different orders, assume nothing. Collect the set of all
3145 parameter registers. */
3146 insn
= find_first_parameter_load (insn
, BB_HEAD (bb
));
3148 /* If we found all the parameter loads, then we want to insert
3149 before the first parameter load.
3151 If we did not find all the parameter loads, then we might have
3152 stopped on the head of the block, which could be a CODE_LABEL.
3153 If we inserted before the CODE_LABEL, then we would be putting
3154 the insn in the wrong basic block. In that case, put the insn
3155 after the CODE_LABEL. Also, respect NOTE_INSN_BASIC_BLOCK. */
3156 while (LABEL_P (insn
)
3157 || NOTE_INSN_BASIC_BLOCK_P (insn
))
3158 insn
= NEXT_INSN (insn
);
3160 new_insn
= emit_insn_before_noloc (pat
, insn
, bb
);
3163 new_insn
= emit_insn_after_noloc (pat
, insn
, bb
);
3168 /* Returns true if it is possible to remove edge E by redirecting
3169 it to the destination of the other edge from E->src. */
3172 rtl_can_remove_branch_p (const_edge e
)
3174 const_basic_block src
= e
->src
;
3175 const_basic_block target
= EDGE_SUCC (src
, EDGE_SUCC (src
, 0) == e
)->dest
;
3176 const_rtx insn
= BB_END (src
), set
;
3178 /* The conditions are taken from try_redirect_by_replacing_jump. */
3179 if (target
== EXIT_BLOCK_PTR
)
3182 if (e
->flags
& (EDGE_ABNORMAL_CALL
| EDGE_EH
))
3185 if (find_reg_note (insn
, REG_CROSSING_JUMP
, NULL_RTX
)
3186 || BB_PARTITION (src
) != BB_PARTITION (target
))
3189 if (!onlyjump_p (insn
)
3190 || tablejump_p (insn
, NULL
, NULL
))
3193 set
= single_set (insn
);
3194 if (!set
|| side_effects_p (set
))
3200 /* Implementation of CFG manipulation for linearized RTL. */
3201 struct cfg_hooks rtl_cfg_hooks
= {
3203 rtl_verify_flow_info
,
3205 rtl_create_basic_block
,
3206 rtl_redirect_edge_and_branch
,
3207 rtl_redirect_edge_and_branch_force
,
3208 rtl_can_remove_branch_p
,
3211 rtl_move_block_after
,
3212 rtl_can_merge_blocks
, /* can_merge_blocks_p */
3216 NULL
, /* can_duplicate_block_p */
3217 NULL
, /* duplicate_block */
3219 rtl_make_forwarder_block
,
3220 rtl_tidy_fallthru_edge
,
3221 rtl_block_ends_with_call_p
,
3222 rtl_block_ends_with_condjump_p
,
3223 rtl_flow_call_edges_add
,
3224 NULL
, /* execute_on_growing_pred */
3225 NULL
, /* execute_on_shrinking_pred */
3226 NULL
, /* duplicate loop for trees */
3227 NULL
, /* lv_add_condition_to_bb */
3228 NULL
, /* lv_adjust_loop_header_phi*/
3229 NULL
, /* extract_cond_bb_edges */
3230 NULL
/* flush_pending_stmts */
3233 /* Implementation of CFG manipulation for cfg layout RTL, where
3234 basic block connected via fallthru edges does not have to be adjacent.
3235 This representation will hopefully become the default one in future
3236 version of the compiler. */
3238 /* We do not want to declare these functions in a header file, since they
3239 should only be used through the cfghooks interface, and we do not want to
3240 move them here since it would require also moving quite a lot of related
3241 code. They are in cfglayout.c. */
3242 extern bool cfg_layout_can_duplicate_bb_p (const_basic_block
);
3243 extern basic_block
cfg_layout_duplicate_bb (basic_block
);
3245 struct cfg_hooks cfg_layout_rtl_cfg_hooks
= {
3247 rtl_verify_flow_info_1
,
3249 cfg_layout_create_basic_block
,
3250 cfg_layout_redirect_edge_and_branch
,
3251 cfg_layout_redirect_edge_and_branch_force
,
3252 rtl_can_remove_branch_p
,
3253 cfg_layout_delete_block
,
3254 cfg_layout_split_block
,
3255 rtl_move_block_after
,
3256 cfg_layout_can_merge_blocks_p
,
3257 cfg_layout_merge_blocks
,
3260 cfg_layout_can_duplicate_bb_p
,
3261 cfg_layout_duplicate_bb
,
3262 cfg_layout_split_edge
,
3263 rtl_make_forwarder_block
,
3265 rtl_block_ends_with_call_p
,
3266 rtl_block_ends_with_condjump_p
,
3267 rtl_flow_call_edges_add
,
3268 NULL
, /* execute_on_growing_pred */
3269 NULL
, /* execute_on_shrinking_pred */
3270 duplicate_loop_to_header_edge
, /* duplicate loop for trees */
3271 rtl_lv_add_condition_to_bb
, /* lv_add_condition_to_bb */
3272 NULL
, /* lv_adjust_loop_header_phi*/
3273 rtl_extract_cond_bb_edges
, /* extract_cond_bb_edges */
3274 NULL
/* flush_pending_stmts */