/* Basic block reordering routines for the GNU compiler.
Copyright (C) 2000 Free Software Foundation, Inc.
- This file is part of GNU CC.
+ This file is part of GCC.
- GNU CC is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
+ GCC is free software; you can redistribute it and/or modify it
+ under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
- GNU CC is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
+ GCC is distributed in the hope that it will be useful, but WITHOUT
+ ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
+ License for more details.
You should have received a copy of the GNU General Public License
- along with GNU CC; see the file COPYING. If not, write to
- the Free Software Foundation, 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
+ along with GCC; see the file COPYING. If not, write to the Free
+ Software Foundation, 59 Temple Place - Suite 330, Boston, MA
+ 02111-1307, USA. */
/* References:
"Profile Guided Code Positioning"
Pettis and Hanson; PLDI '90.
+
+ TODO:
+
+ (1) Consider:
+
+ if (p) goto A; // predict taken
+ foo ();
+ A:
+ if (q) goto B; // predict taken
+ bar ();
+ B:
+ baz ();
+ return;
+
+ We'll currently reorder this as
+
+ if (!p) goto C;
+ A:
+ if (!q) goto D;
+ B:
+ baz ();
+ return;
+ D:
+ bar ();
+ goto B;
+ C:
+ foo ();
+ goto A;
+
+ A better ordering is
+
+ if (!p) goto C;
+ if (!q) goto D;
+ B:
+ baz ();
+ return;
+ C:
+ foo ();
+ if (q) goto B;
+ D:
+ bar ();
+ goto B;
+
+ This requires that we be able to duplicate the jump at A, and
+ adjust the graph traversal such that greedy placement doesn't
+ fix D before C is considered.
+
+ (2) Coordinate with shorten_branches to minimize the number of
+ long branches.
+
+ (3) Invent a method by which sufficiently non-predicted code can
+ be moved to either the end of the section or another section
+ entirely. Some sort of NOTE_INSN note would work fine.
+
+ This completely scroggs all debugging formats, so the user
+ would have to explicitly ask for it.
*/
#include "config.h"
#include "system.h"
#include "tree.h"
#include "rtl.h"
-#include "tm_p.h"
-#include "basic-block.h"
-#include "insn-config.h"
-#include "regs.h"
#include "hard-reg-set.h"
+#include "basic-block.h"
#include "flags.h"
#include "output.h"
-#include "function.h"
-#include "except.h"
-#include "toplev.h"
-#include "recog.h"
-#include "insn-flags.h"
-#include "expr.h"
-#include "obstack.h"
-
-
-/* The contents of the current function definition are allocated
- in this obstack, and all are freed at the end of the function.
- For top-level functions, this is temporary_obstack.
- Separate obstacks are made for nested functions. */
-
-extern struct obstack *function_obstack;
-
-
-/* Structure to hold information about lexical scopes. */
-typedef struct scope_def
-{
- int level;
-
- /* The NOTE_INSN_BLOCK_BEG that started this scope. */
- rtx note_beg;
-
- /* The NOTE_INSN_BLOCK_END that ended this scope. */
- rtx note_end;
-
- /* The bb containing note_beg (if any). */
- basic_block bb_beg;
-
- /* The bb containing note_end (if any). */
- basic_block bb_end;
-
- /* List of basic blocks contained within this scope. */
- basic_block *bbs;
-
- /* Number of blocks contained within this scope. */
- int num_bbs;
-
- /* The outer scope or NULL if outermost scope. */
- struct scope_def *outer;
-
- /* The first inner scope or NULL if innermost scope. */
- struct scope_def *inner;
-
- /* The last inner scope or NULL if innermost scope. */
- struct scope_def *inner_last;
-
- /* Link to the next (sibling) scope. */
- struct scope_def *next;
-} *scope;
-
-/* Structure to hold information about the scope forest. */
-typedef struct
-{
- /* Number of trees in forest. */
- int num_trees;
-
- /* List of tree roots. */
- scope *trees;
-} scope_forest_info;
-
-
-typedef struct reorder_block_def {
- int flags;
- int index;
- basic_block add_jump;
- rtx eff_head;
- rtx eff_end;
- scope scope;
-} *reorder_block_def;
-
-static struct reorder_block_def rbd_init
-= {
- 0, /* flags */
- 0, /* index */
- NULL, /* add_jump */
- NULL_RTX, /* eff_head */
- NULL_RTX, /* eff_end */
- NULL /* scope */
-};
+#include "cfglayout.h"
-
-#define REORDER_BLOCK_HEAD 0x1
-#define REORDER_BLOCK_VISITED 0x2
-
-#define REORDER_BLOCK_FLAGS(bb) \
- ((reorder_block_def) (bb)->aux)->flags
-
-#define REORDER_BLOCK_INDEX(bb) \
- ((reorder_block_def) (bb)->aux)->index
-
-#define REORDER_BLOCK_ADD_JUMP(bb) \
- ((reorder_block_def) (bb)->aux)->add_jump
-
-#define REORDER_BLOCK_EFF_HEAD(bb) \
- ((reorder_block_def) (bb)->aux)->eff_head
-
-#define REORDER_BLOCK_EFF_END(bb) \
- ((reorder_block_def) (bb)->aux)->eff_end
-
-#define REORDER_BLOCK_SCOPE(bb) \
- ((reorder_block_def) (bb)->aux)->scope
-
-
-static int reorder_index;
-static basic_block reorder_last_visited;
-
-
-/* Local function prototypes. */
-static rtx skip_insns_after_block PARAMS ((basic_block));
-static basic_block get_common_dest PARAMS ((basic_block, basic_block));
-static basic_block chain_reorder_blocks PARAMS ((edge, basic_block));
-static void make_reorder_chain PARAMS ((basic_block));
-static void fixup_reorder_chain PARAMS ((void));
-#ifdef ENABLE_CHECKING
-static void verify_insn_chain PARAMS ((void));
+#ifndef HAVE_epilogue
+#define HAVE_epilogue 0
#endif
-static void relate_bbs_with_scopes PARAMS ((scope));
-static scope make_new_scope PARAMS ((int, rtx));
-static void build_scope_forest PARAMS ((scope_forest_info *));
-static void remove_scope_notes PARAMS ((void));
-static void insert_intra_1 PARAMS ((scope, rtx *));
-static void insert_intra_bb_scope_notes PARAMS ((basic_block));
-static void insert_inter_bb_scope_notes PARAMS ((basic_block, basic_block));
-static void rebuild_scope_notes PARAMS ((scope_forest_info *));
-static void free_scope_forest_1 PARAMS ((scope));
-static void free_scope_forest PARAMS ((scope_forest_info *));
-void dump_scope_forest PARAMS ((scope_forest_info *));
-static void dump_scope_forest_1 PARAMS ((scope, int));
-static rtx get_next_bb_note PARAMS ((rtx));
-static rtx get_prev_bb_note PARAMS ((rtx));
-
-/* Skip over inter-block insns occurring after BB which are typically
- associated with BB (e.g., barriers). If there are any such insns,
- we return the last one. Otherwise, we return the end of BB. */
-
-static rtx
-skip_insns_after_block (bb)
- basic_block bb;
-{
- rtx insn, last_insn;
-
- last_insn = bb->end;
-
- if (bb == EXIT_BLOCK_PTR)
- return 0;
-
- for (insn = NEXT_INSN (bb->end);
- insn;
- last_insn = insn, insn = NEXT_INSN (insn))
- {
- if (bb->index + 1 != n_basic_blocks
- && insn == BASIC_BLOCK (bb->index + 1)->head)
- break;
-
- if (GET_CODE (insn) == BARRIER
- || GET_CODE (insn) == JUMP_INSN
- || (GET_CODE (insn) == NOTE
- && (NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_END
- || NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)))
- continue;
-
- if (GET_CODE (insn) == CODE_LABEL
- && GET_CODE (NEXT_INSN (insn)) == JUMP_INSN
- && (GET_CODE (PATTERN (NEXT_INSN (insn))) == ADDR_VEC
- || GET_CODE (PATTERN (NEXT_INSN (insn))) == ADDR_DIFF_VEC))
- {
- insn = NEXT_INSN (insn);
- continue;
- }
-
- /* Skip to next non-deleted insn. */
- if (GET_CODE (insn) == NOTE
- && (NOTE_LINE_NUMBER (insn) == NOTE_INSN_DELETED
- || NOTE_LINE_NUMBER (insn) == NOTE_INSN_DELETED_LABEL))
- continue;
-
- break;
- }
-
- return last_insn;
-}
-
-
-/* Return common destination for blocks BB0 and BB1. */
-
-static basic_block
-get_common_dest (bb0, bb1)
- basic_block bb0, bb1;
-{
- edge e0, e1;
-
- for (e0 = bb0->succ; e0; e0 = e0->succ_next)
- {
- for (e1 = bb1->succ; e1; e1 = e1->succ_next)
- {
- if (e0->dest == e1->dest)
- {
- return e0->dest;
- }
- }
- }
- return 0;
-}
-
-
-/* Move the destination block for edge E after chain end block CEB
- Adding jumps and labels is deferred until fixup_reorder_chain. */
-
-static basic_block
-chain_reorder_blocks (e, ceb)
- edge e;
- basic_block ceb;
-{
- basic_block sb = e->src;
- basic_block db = e->dest;
- rtx cebe_insn, dbh_insn, dbe_insn;
- edge ee, last_edge;
- edge e_fallthru, e_jump;
-
- enum cond_types {NO_COND, PREDICT_THEN_WITH_ELSE, PREDICT_ELSE,
- PREDICT_THEN_NO_ELSE, PREDICT_NOT_THEN_NO_ELSE};
- enum cond_types cond_type;
- enum cond_block_types {NO_COND_BLOCK, THEN_BLOCK, ELSE_BLOCK,
- NO_ELSE_BLOCK};
- enum cond_block_types cond_block_type;
-
- if (rtl_dump_file)
- fprintf (rtl_dump_file,
- "Edge from basic block %d to basic block %d last visited %d\n",
- sb->index, db->index, ceb->index);
- cebe_insn = REORDER_BLOCK_EFF_END (ceb);
-
- /* Blocks are in original order. */
- if (sb->index == ceb->index
- && ceb->index + 1 == db->index && NEXT_INSN (cebe_insn))
- return db;
-
- e_fallthru = e_jump = e;
-
- /* Get the type of block and type of condition. */
- cond_type = NO_COND;
- cond_block_type = NO_COND_BLOCK;
- if (GET_CODE (sb->end) == JUMP_INSN && ! simplejump_p (sb->end)
- && condjump_p (sb->end))
- {
- if (e->flags & EDGE_FALLTHRU)
- {
- if (e == sb->succ)
- e_jump = sb->succ->succ_next;
- else if (e == sb->succ->succ_next)
- e_jump = sb->succ;
- else
- abort ();
- }
- else
- {
- if (e == sb->succ)
- e_fallthru = sb->succ->succ_next;
- else if (e == sb->succ->succ_next)
- e_fallthru = sb->succ;
- else
- abort ();
- }
-
- if (e->flags & EDGE_FALLTHRU)
- cond_block_type = THEN_BLOCK;
- else if (get_common_dest (e_fallthru->dest, sb))
- cond_block_type = NO_ELSE_BLOCK;
- else
- cond_block_type = ELSE_BLOCK;
-
- if (get_common_dest (e_fallthru->dest, sb))
- {
- if (cond_block_type == THEN_BLOCK)
- {
- if (! (REORDER_BLOCK_FLAGS (e->dest)
- & REORDER_BLOCK_VISITED))
- cond_type = PREDICT_THEN_NO_ELSE;
- else
- cond_type = PREDICT_NOT_THEN_NO_ELSE;
- }
- else if (cond_block_type == NO_ELSE_BLOCK)
- {
- if (! (REORDER_BLOCK_FLAGS (e->dest)
- & REORDER_BLOCK_VISITED))
- cond_type = PREDICT_NOT_THEN_NO_ELSE;
- else
- cond_type = PREDICT_THEN_NO_ELSE;
- }
- }
- else
- {
- if (cond_block_type == THEN_BLOCK)
- {
- if (! (REORDER_BLOCK_FLAGS (e->dest)
- & REORDER_BLOCK_VISITED))
- cond_type = PREDICT_THEN_WITH_ELSE;
- else
- cond_type = PREDICT_ELSE;
- }
- else if (cond_block_type == ELSE_BLOCK
- && e_fallthru->dest != EXIT_BLOCK_PTR)
- {
- if (! (REORDER_BLOCK_FLAGS (e->dest)
- & REORDER_BLOCK_VISITED))
- cond_type = PREDICT_ELSE;
- else
- cond_type = PREDICT_THEN_WITH_ELSE;
- }
- }
- }
-
- if (rtl_dump_file)
- {
- static const char * cond_type_str [] = {"not cond jump", "predict then",
- "predict else",
- "predict then w/o else",
- "predict not then w/o else"};
- static const char * cond_block_type_str [] = {"not then or else block",
- "then block",
- "else block",
- "then w/o else block"};
-
- fprintf (rtl_dump_file, " %s (looking at %s)\n",
- cond_type_str[(int)cond_type],
- cond_block_type_str[(int)cond_block_type]);
- }
-
- /* Reflect that then block will move and we'll jump to it. */
- if (cond_block_type != THEN_BLOCK
- && (cond_type == PREDICT_ELSE
- || cond_type == PREDICT_NOT_THEN_NO_ELSE))
- {
- if (rtl_dump_file)
- fprintf (rtl_dump_file,
- " then jump from block %d to block %d\n",
- sb->index, e_fallthru->dest->index);
-
- /* Jump to reordered then block. */
- REORDER_BLOCK_ADD_JUMP (sb) = e_fallthru->dest;
- }
-
- /* Reflect that then block will jump back when we have no else. */
- if (cond_block_type != THEN_BLOCK
- && cond_type == PREDICT_NOT_THEN_NO_ELSE)
- {
- basic_block jbb = e_fallthru->dest;
- for (ee = jbb->succ;
- ee && ! (ee->flags & EDGE_FALLTHRU);
- ee = ee->succ_next)
- continue;
-
- if (ee && ! (GET_CODE (jbb->end) == JUMP_INSN
- && ! simplejump_p (jbb->end)))
- {
- REORDER_BLOCK_ADD_JUMP (jbb) = ee->dest;
- }
- }
-
- /* Reflect that else block will jump back. */
- if (cond_block_type == ELSE_BLOCK
- && (cond_type == PREDICT_THEN_WITH_ELSE || cond_type == PREDICT_ELSE))
- {
- last_edge=db->succ;
-
- if (last_edge
- && last_edge->dest != EXIT_BLOCK_PTR
- && GET_CODE (last_edge->dest->head) == CODE_LABEL
- && ! (GET_CODE (db->end) == JUMP_INSN))
- {
- if (rtl_dump_file)
- fprintf (rtl_dump_file,
- " else jump from block %d to block %d\n",
- db->index, last_edge->dest->index);
-
- REORDER_BLOCK_ADD_JUMP (db) = last_edge->dest;
- }
- }
-
- /* This block's successor has already been reordered. This can happen
- when we reorder a chain starting at a then or else. */
- for (last_edge = db->succ;
- last_edge && ! (last_edge->flags & EDGE_FALLTHRU);
- last_edge = last_edge->succ_next)
- continue;
- if (last_edge
- && last_edge->dest != EXIT_BLOCK_PTR
- && (REORDER_BLOCK_FLAGS (last_edge->dest)
- & REORDER_BLOCK_VISITED))
- {
- if (rtl_dump_file)
- fprintf (rtl_dump_file,
- " end of chain jump from block %d to block %d\n",
- db->index, last_edge->dest->index);
-
- REORDER_BLOCK_ADD_JUMP (db) = last_edge->dest;
- }
-
- dbh_insn = REORDER_BLOCK_EFF_HEAD (db);
- cebe_insn = REORDER_BLOCK_EFF_END (ceb);
- dbe_insn = REORDER_BLOCK_EFF_END (db);
-
- /* Rechain predicted block. */
- NEXT_INSN (cebe_insn) = dbh_insn;
- PREV_INSN (dbh_insn) = cebe_insn;
-
- if (db->index != n_basic_blocks - 1)
- NEXT_INSN (dbe_insn) = 0;
-
- return db;
-}
-
-
-/* Reorder blocks starting at block BB. */
+/* Local function prototypes. */
+static void make_reorder_chain PARAMS ((void));
+static basic_block make_reorder_chain_1 PARAMS ((basic_block, basic_block));
+\f
+/* Compute an ordering for a subgraph beginning with block BB. Record the
+ ordering in RBI()->index and chained through RBI()->next. */
static void
-make_reorder_chain (bb)
- basic_block bb;
+make_reorder_chain ()
{
- edge e;
- basic_block visited_edge = NULL;
- rtx block_end;
- int probability;
-
- if (bb == EXIT_BLOCK_PTR)
- return;
-
- /* Find the most probable block. */
- e = bb->succ;
- block_end = bb->end;
- if (GET_CODE (block_end) == JUMP_INSN && condjump_p (block_end))
- {
- rtx note = find_reg_note (block_end, REG_BR_PROB, 0);
-
- if (note)
- probability = INTVAL (XEXP (note, 0));
- else
- probability = 0;
-
- if (probability >= REG_BR_PROB_BASE / 2)
- e = bb->succ->succ_next;
- }
-
- /* Add chosen successor to chain and recurse on it. */
- if (e && e->dest != EXIT_BLOCK_PTR
- && e->dest != e->src
- && (! (REORDER_BLOCK_FLAGS (e->dest) & REORDER_BLOCK_VISITED)
- || (REORDER_BLOCK_FLAGS (e->dest) == REORDER_BLOCK_HEAD)))
- {
- if (! (REORDER_BLOCK_FLAGS (bb) & REORDER_BLOCK_VISITED))
- {
- REORDER_BLOCK_FLAGS (bb) |= REORDER_BLOCK_HEAD;
- REORDER_BLOCK_INDEX (bb) = reorder_index++;
- REORDER_BLOCK_FLAGS (bb) |= REORDER_BLOCK_VISITED;
- }
-
- if (REORDER_BLOCK_FLAGS (e->dest) & REORDER_BLOCK_VISITED)
- REORDER_BLOCK_FLAGS (e->dest) &= ~REORDER_BLOCK_HEAD;
-
- visited_edge = e->dest;
-
- reorder_last_visited = chain_reorder_blocks (e, bb);
-
- if (e->dest
- && ! (REORDER_BLOCK_FLAGS (e->dest)
- & REORDER_BLOCK_VISITED))
- make_reorder_chain (e->dest);
- }
- else
- {
- if (! (REORDER_BLOCK_FLAGS (bb) & REORDER_BLOCK_VISITED))
- {
- REORDER_BLOCK_INDEX (bb) = reorder_index++;
- REORDER_BLOCK_FLAGS (bb) |= REORDER_BLOCK_VISITED;
- }
- }
+ basic_block last_block = NULL;
+ basic_block prev = NULL;
+ int nbb_m1 = n_basic_blocks - 1;
+ basic_block next;
- /* Recurse on the successors. */
- for (e = bb->succ; e; e = e->succ_next)
+ /* If we've not got epilogue in RTL, we must fallthru to the exit.
+ Force the last block to be at the end. */
+ /* ??? Some ABIs (e.g. MIPS) require the return insn to be at the
+ end of the function for stack unwinding purposes. */
+ if (! HAVE_epilogue)
{
- if (e->dest && e->dest == EXIT_BLOCK_PTR)
- continue;
-
- if (e->dest
- && e->dest != e->src
- && e->dest != visited_edge
- && ! (REORDER_BLOCK_FLAGS (e->dest)
- & REORDER_BLOCK_VISITED))
- {
- reorder_last_visited
- = chain_reorder_blocks (e, reorder_last_visited);
- make_reorder_chain (e->dest);
- }
+ last_block = BASIC_BLOCK (nbb_m1);
+ RBI (last_block)->visited = 1;
+ nbb_m1 -= 1;
}
-}
-
-
-/* Fixup jumps and labels after reordering basic blocks. */
-
-static void
-fixup_reorder_chain ()
-{
- int i, j;
- rtx insn;
- int orig_num_blocks = n_basic_blocks;
-
- /* Set the new last insn. */
- {
- int max_val = 0;
- int max_index = 0;
- for (j = 0; j < n_basic_blocks; j++)
- {
- int val = REORDER_BLOCK_INDEX (BASIC_BLOCK (j));
- if (val > max_val)
- {
- max_val = val;
- max_index = j;
- }
- }
- insn = REORDER_BLOCK_EFF_END (BASIC_BLOCK (max_index));
- NEXT_INSN (insn) = NULL_RTX;
- set_last_insn (insn);
- }
- /* Add jumps and labels to fixup blocks. */
- for (i = 0; i < orig_num_blocks; i++)
+ /* Loop until we've placed every block. */
+ do
{
- int need_block = 0;
- basic_block bbi = BASIC_BLOCK (i);
- if (REORDER_BLOCK_ADD_JUMP (bbi))
- {
- rtx label_insn, jump_insn, barrier_insn;
-
- if (GET_CODE (REORDER_BLOCK_ADD_JUMP (bbi)->head) == CODE_LABEL)
- label_insn = REORDER_BLOCK_ADD_JUMP (bbi)->head;
- else
- {
- rtx new_label = gen_label_rtx ();
- label_insn = emit_label_before (new_label,
- REORDER_BLOCK_ADD_JUMP (bbi)->head);
- REORDER_BLOCK_ADD_JUMP (bbi)->head = label_insn;
- }
-
- if (GET_CODE (bbi->end) != JUMP_INSN)
- {
- jump_insn = emit_jump_insn_after (gen_jump (label_insn),
- bbi->end);
- bbi->end = jump_insn;
- need_block = 0;
- }
- else
- {
- jump_insn = emit_jump_insn_after (gen_jump (label_insn),
- REORDER_BLOCK_EFF_END (bbi));
- need_block = 1;
- }
-
- JUMP_LABEL (jump_insn) = label_insn;
- ++LABEL_NUSES (label_insn);
- barrier_insn = emit_barrier_after (jump_insn);
-
- /* Add block for jump. Typically this is when a then is not
- predicted and we are jumping to the moved then block. */
- if (need_block)
- {
- basic_block nb;
-
- VARRAY_GROW (basic_block_info, ++n_basic_blocks);
- create_basic_block (n_basic_blocks - 1, jump_insn,
- jump_insn, NULL);
- nb = BASIC_BLOCK (n_basic_blocks - 1);
- nb->global_live_at_start
- = OBSTACK_ALLOC_REG_SET (function_obstack);
- nb->global_live_at_end
- = OBSTACK_ALLOC_REG_SET (function_obstack);
-
- COPY_REG_SET (nb->global_live_at_start,
- bbi->global_live_at_start);
- COPY_REG_SET (nb->global_live_at_end,
- bbi->global_live_at_start);
- BASIC_BLOCK (nb->index)->local_set = 0;
-
- nb->aux = xcalloc (1, sizeof (struct reorder_block_def));
- REORDER_BLOCK_INDEX (nb) = REORDER_BLOCK_INDEX (bbi) + 1;
- /* Relink to new block. */
- nb->succ = bbi->succ;
- nb->succ->src = nb;
-
- make_edge (NULL, bbi, nb, 0);
- bbi->succ->succ_next
- = bbi->succ->succ_next->succ_next;
- nb->succ->succ_next = 0;
- /* Fix reorder block index to reflect new block. */
- for (j = 0; j < n_basic_blocks - 1; j++)
- {
- basic_block bbj = BASIC_BLOCK (j);
- if (REORDER_BLOCK_INDEX (bbj)
- >= REORDER_BLOCK_INDEX (bbi) + 1)
- REORDER_BLOCK_INDEX (bbj)++;
- }
- REORDER_BLOCK_SCOPE (nb) = REORDER_BLOCK_SCOPE (bbi);
- REORDER_BLOCK_EFF_HEAD (nb) = nb->head;
- REORDER_BLOCK_EFF_END (nb) = barrier_insn;
- }
- else
- REORDER_BLOCK_EFF_END (bbi) = barrier_insn;
- }
- }
-}
-
-
-/* Perform sanity checks on the insn chain.
- 1. Check that next/prev pointers are consistent in both the forward and
- reverse direction.
- 2. Count insns in chain, going both directions, and check if equal.
- 3. Check that get_last_insn () returns the actual end of chain. */
-#ifdef ENABLE_CHECKING
-static void
-verify_insn_chain ()
-{
- rtx x,
- prevx,
- nextx;
- int insn_cnt1,
- insn_cnt2;
+ int i;
- prevx = NULL;
- insn_cnt1 = 1;
- for (x = get_insns (); x; x = NEXT_INSN (x))
- {
- if (PREV_INSN (x) != prevx)
- {
- fprintf (stderr, "Forward traversal: insn chain corrupt.\n");
- fprintf (stderr, "previous insn:\n");
- debug_rtx (prevx);
- fprintf (stderr, "current insn:\n");
- debug_rtx (x);
- abort ();
- }
- ++insn_cnt1;
- prevx = x;
- }
+ next = NULL;
- if (prevx != get_last_insn ())
- {
- fprintf (stderr, "last_insn corrupt.\n");
- abort ();
- }
+ /* Find the next unplaced block. */
+ /* ??? Get rid of this loop, and track which blocks are not yet
+ placed more directly, so as to avoid the O(N^2) worst case.
+ Perhaps keep a doubly-linked list of all to-be-placed blocks;
+ remove from the list as we place. The head of that list is
+ what we're looking for here. */
- nextx = NULL;
- insn_cnt2 = 1;
- for (x = get_last_insn (); x; x = PREV_INSN (x))
- {
- if (NEXT_INSN (x) != nextx)
+ for (i = 0; i <= nbb_m1 && !next; ++i)
{
- fprintf (stderr, "Reverse traversal: insn chain corrupt.\n");
- fprintf (stderr, "current insn:\n");
- debug_rtx (x);
- fprintf (stderr, "next insn:\n");
- debug_rtx (nextx);
- abort ();
+ basic_block bb = BASIC_BLOCK (i);
+ if (! RBI (bb)->visited)
+ next = bb;
}
- ++insn_cnt2;
- nextx = x;
+ if (next)
+ prev = make_reorder_chain_1 (next, prev);
}
+ while (next);
- if (insn_cnt1 != insn_cnt2)
- {
- fprintf (stderr, "insn_cnt1 (%d) not equal to insn_cnt2 (%d).\n",
- insn_cnt1, insn_cnt2);
- abort ();
- }
-}
-#endif
-
-static rtx
-get_next_bb_note (x)
- rtx x;
-{
- while (x)
+ /* Terminate the chain. */
+ if (! HAVE_epilogue)
{
- if (GET_CODE (x) == NOTE
- && NOTE_LINE_NUMBER (x) == NOTE_INSN_BASIC_BLOCK)
- return x;
- x = NEXT_INSN (x);
+ RBI (prev)->next = last_block;
+ prev = last_block;
}
- return NULL;
+ RBI (prev)->next = NULL;
}
+/* A helper function for make_reorder_chain.
-static rtx
-get_prev_bb_note (x)
- rtx x;
-{
- while (x)
- {
- if (GET_CODE (x) == NOTE
- && NOTE_LINE_NUMBER (x) == NOTE_INSN_BASIC_BLOCK)
- return x;
- x = PREV_INSN (x);
- }
- return NULL;
-}
-
+ We do not follow EH edges, or non-fallthru edges to noreturn blocks.
+ These are assumed to be the error condition and we wish to cluster
+ all of them at the very end of the function for the benefit of cache
+ locality for the rest of the function.
-/* Determine and record the relationships between basic blocks and
- scopes in scope tree S. */
+ ??? We could do slightly better by noticing earlier that some subgraph
+ has all paths leading to noreturn functions, but for there to be more
+ than one block in such a subgraph is rare. */
-static void
-relate_bbs_with_scopes (s)
- scope s;
+static basic_block
+make_reorder_chain_1 (bb, prev)
+ basic_block bb;
+ basic_block prev;
{
- scope p;
- int i, bbi1, bbi2, bbs_spanned;
- rtx bbnote;
-
- for (p = s->inner; p; p = p->next)
- relate_bbs_with_scopes (p);
-
- bbi1 = bbi2 = -1;
- bbs_spanned = 0;
+ edge e;
+ basic_block next;
+ rtx note;
- /* If the begin and end notes are both inside the same basic block,
- or if they are both outside of basic blocks, then we know immediately
- how they are related. Otherwise, we need to poke around to make the
- determination. */
- if (s->bb_beg != s->bb_end)
+ /* Mark this block visited. */
+ if (prev)
{
- if (s->bb_beg && s->bb_end)
- {
- /* Both notes are in different bbs. This implies that all the
- basic blocks spanned by the pair of notes are contained in
- this scope. */
- bbi1 = s->bb_beg->index;
- bbi2 = s->bb_end->index;
- bbs_spanned = 1;
- }
- else if (! s->bb_beg)
- {
- /* First note is outside of a bb. If the scope spans more than
- one basic block, then they all are contained within this
- scope. Otherwise, this scope is contained within the basic
- block. */
- bbnote = get_next_bb_note (s->note_beg);
- if (! bbnote)
- abort ();
- if (NOTE_BASIC_BLOCK (bbnote) == s->bb_end)
- {
- bbs_spanned = 0;
- s->bb_beg = NOTE_BASIC_BLOCK (bbnote);
- }
- else
- {
- bbi1 = NOTE_BASIC_BLOCK (bbnote)->index;
- bbi2 = s->bb_end->index;
- s->bb_end = NULL;
- bbs_spanned = 1;
- }
- }
- else /* ! s->bb_end */
- {
- /* Second note is outside of a bb. If the scope spans more than
- one basic block, then they all are contained within this
- scope. Otherwise, this scope is contained within the basic
- block. */
- bbnote = get_prev_bb_note (s->note_end);
- if (! bbnote)
- abort ();
- if (NOTE_BASIC_BLOCK (bbnote) == s->bb_beg)
- {
- bbs_spanned = 0;
- s->bb_end = NOTE_BASIC_BLOCK (bbnote);
- }
- else
- {
- bbi1 = s->bb_beg->index;
- bbi2 = NOTE_BASIC_BLOCK (bbnote)->index;
- s->bb_beg = NULL;
- bbs_spanned = 1;
- }
- }
- }
- else
- {
- if (s->bb_beg)
- /* Both notes are in the same bb, which implies the block
- contains this scope. */
- bbs_spanned = 0;
- else
- {
- rtx x1, x2;
- /* Both notes are outside of any bbs. This implies that all the
- basic blocks spanned by the pair of notes are contained in
- this scope.
- There is a degenerate case to consider. If the notes do not
- span any basic blocks, then it is an empty scope that can
- safely be deleted or ignored. Mark these with level = -1. */
+ restart:
+ RBI (prev)->next = bb;
- x1 = get_next_bb_note (s->note_beg);
- x2 = get_prev_bb_note (s->note_end);
- if (! (x1 && x2))
- {
- s->level = -1;
- bbs_spanned = 0;
- }
- else
- {
- bbi1 = NOTE_BASIC_BLOCK (x1)->index;
- bbi2 = NOTE_BASIC_BLOCK (x2)->index;
- bbs_spanned = 1;
- }
- }
- }
-
-
- /* If the scope spans one or more basic blocks, we record them. We
- only record the bbs that are immediately contained within this
- scope. Note that if a scope is contained within a bb, we can tell
- by checking that bb_beg = bb_end and that they are non-null. */
- if (bbs_spanned)
- {
- int j = 0;
-
- s->num_bbs = 0;
- for (i = bbi1; i <= bbi2; i++)
- if (! REORDER_BLOCK_SCOPE (BASIC_BLOCK (i)))
- s->num_bbs++;
-
- s->bbs = xcalloc (s->num_bbs, sizeof (struct basic_block_def));
- for (i = bbi1; i <= bbi2; i++)
- {
- basic_block curr_bb = BASIC_BLOCK (i);
- if (! REORDER_BLOCK_SCOPE (curr_bb))
- {
- s->bbs[j++] = curr_bb;
- REORDER_BLOCK_SCOPE (curr_bb) = s;
- }
- }
+ if (rtl_dump_file && prev->index + 1 != bb->index)
+ fprintf (rtl_dump_file, "Reordering block %d after %d\n",
+ bb->index, prev->index);
}
else
- s->num_bbs = 0;
-}
-
-
-/* Allocate and initialize a new scope structure with scope level LEVEL,
- and record the NOTE beginning the scope. */
-
-static scope
-make_new_scope (level, note)
- int level;
- rtx note;
-{
- scope new_scope = xcalloc (1, sizeof (struct scope_def));
- new_scope->level = level;
- new_scope->note_beg = note;
- new_scope->note_end = NULL;
- new_scope->bb_beg = NULL;
- new_scope->bb_end = NULL;
- new_scope->inner = NULL;
- new_scope->inner_last = NULL;
- new_scope->outer = NULL;
- new_scope->next = NULL;
- new_scope->num_bbs = 0;
- new_scope->bbs = NULL;
- return new_scope;
-}
-
-
-/* Build a forest representing the scope structure of the function.
- Return a pointer to a structure describing the forest. */
-
-static void
-build_scope_forest (forest)
- scope_forest_info *forest;
-{
- rtx x;
- int level, bbi, i;
- basic_block curr_bb;
- scope root, curr_scope;
-
- forest->num_trees = 0;
- forest->trees = NULL;
- level = -1;
- root = NULL;
- curr_bb = NULL;
- bbi = 0;
- for (x = get_insns (); x; x = NEXT_INSN (x))
{
- if (bbi < n_basic_blocks && x == BASIC_BLOCK (bbi)->head)
- curr_bb = BASIC_BLOCK (bbi);
-
- if (GET_CODE (x) == NOTE)
- {
- if (NOTE_LINE_NUMBER (x) == NOTE_INSN_BLOCK_BEG)
- {
- if (root)
- {
- scope new_scope;
- if (! curr_scope)
- abort();
- level++;
- new_scope = make_new_scope (level, x);
- new_scope->outer = curr_scope;
- new_scope->next = NULL;
- if (! curr_scope->inner)
- {
- curr_scope->inner = new_scope;
- curr_scope->inner_last = new_scope;
- }
- else
- {
- curr_scope->inner_last->next = new_scope;
- curr_scope->inner_last = new_scope;
- }
- curr_scope = curr_scope->inner_last;
- }
- else
- {
- int ntrees = forest->num_trees;
- level++;
- curr_scope = make_new_scope (level, x);
- root = curr_scope;
- if (ntrees == 0)
- forest->trees = xcalloc (1, sizeof (scope));
- else
- forest->trees = xrealloc (forest->trees,
- sizeof (scope) * (ntrees + 1));
- forest->trees[forest->num_trees++] = root;
- }
- curr_scope->bb_beg = curr_bb;
- }
- else if (NOTE_LINE_NUMBER (x) == NOTE_INSN_BLOCK_END)
- {
- curr_scope->bb_end = curr_bb;
- curr_scope->note_end = x;
- level--;
- curr_scope = curr_scope->outer;
- if (level == -1)
- root = NULL;
- }
- } /* if note */
-
- if (curr_bb && curr_bb->end == x)
- {
- curr_bb = NULL;
- bbi++;
- }
-
- } /* for */
-
- for (i = 0; i < forest->num_trees; i++)
- relate_bbs_with_scopes (forest->trees[i]);
-}
-
-
-/* Remove all the NOTE_INSN_BLOCK_BEG and NOTE_INSN_BLOCK_END notes from
- the insn chain. */
-
-static void
-remove_scope_notes ()
-{
- rtx x, next;
- basic_block currbb = NULL;
-
- for (x = get_insns (); x; x = next)
- {
- next = NEXT_INSN (x);
- if (GET_CODE (x) == NOTE
- && NOTE_LINE_NUMBER (x) == NOTE_INSN_BASIC_BLOCK)
- currbb = NOTE_BASIC_BLOCK (x);
-
- if (GET_CODE (x) == NOTE
- && (NOTE_LINE_NUMBER (x) == NOTE_INSN_BLOCK_BEG
- || NOTE_LINE_NUMBER (x) == NOTE_INSN_BLOCK_END))
- {
- /* Check if the scope note happens to be the end of a bb. */
- if (currbb && x == currbb->end)
- currbb->end = PREV_INSN (x);
- if (currbb && x == currbb->head)
- abort ();
-
- if (PREV_INSN (x))
- {
- NEXT_INSN (PREV_INSN (x)) = next;
- PREV_INSN (next) = PREV_INSN (x);
-
- NEXT_INSN (x) = NULL;
- PREV_INSN (x) = NULL;
- }
- else
- abort ();
- }
- }
-}
-
-
-/* Insert scope note pairs for a contained scope tree S after insn IP. */
-static void
-insert_intra_1 (s, ip)
- scope s;
- rtx *ip;
-{
- scope p;
-
- if (NOTE_BLOCK (s->note_beg))
- {
- *ip = emit_note_after (NOTE_INSN_BLOCK_BEG, *ip);
- NOTE_BLOCK (*ip) = NOTE_BLOCK (s->note_beg);
- }
-
- for (p = s->inner; p; p = p->next)
- insert_intra_1 (p, ip);
-
- if (NOTE_BLOCK (s->note_beg))
- {
- *ip = emit_note_after (NOTE_INSN_BLOCK_END, *ip);
- NOTE_BLOCK (*ip) = NOTE_BLOCK (s->note_end);
+ if (bb->index != 0)
+ abort ();
}
-}
-
-
-/* Insert NOTE_INSN_BLOCK_END notes and NOTE_INSN_BLOCK_BEG notes for
- scopes that are contained within BB. */
-
-static void
-insert_intra_bb_scope_notes (bb)
- basic_block bb;
-{
- scope s = REORDER_BLOCK_SCOPE (bb);
- scope p;
- rtx ip;
+ RBI (bb)->visited = 1;
+ prev = bb;
- if (! s)
- return;
+ if (bb->succ == NULL)
+ return prev;
- ip = bb->head;
- if (GET_CODE (ip) == CODE_LABEL)
- ip = NEXT_INSN (ip);
+ /* Find the most probable block. */
- for (p = s->inner; p; p = p->next)
+ next = NULL;
+ if (any_condjump_p (bb->end)
+ && (note = find_reg_note (bb->end, REG_BR_PROB, 0)) != NULL)
{
- if (p->bb_beg != NULL && p->bb_beg == p->bb_end && p->bb_beg == bb)
- insert_intra_1 (p, &ip);
- }
-}
-
-
-/* Given two consecutive basic blocks BB1 and BB2 with different scopes,
- insert NOTE_INSN_BLOCK_END notes after BB1 and NOTE_INSN_BLOCK_BEG
- notes before BB2 such that the notes are correctly balanced. If BB1 or
- BB2 is NULL, we are inserting scope notes for the first and last basic
- blocks, respectively. */
+ int taken, probability;
+ edge e_taken, e_fall;
-static void
-insert_inter_bb_scope_notes (bb1, bb2)
- basic_block bb1;
- basic_block bb2;
-{
- rtx ip;
- scope com;
+ probability = INTVAL (XEXP (note, 0));
+ taken = probability > REG_BR_PROB_BASE / 2;
- /* It is possible that a basic block is not contained in any scope.
- In that case, we either open or close a scope but not both. */
- if (bb1 && bb2)
- {
- scope s1 = REORDER_BLOCK_SCOPE (bb1);
- scope s2 = REORDER_BLOCK_SCOPE (bb2);
- if (! s1 && ! s2)
- return;
- if (! s1)
- bb1 = NULL;
- else if (! s2)
- bb2 = NULL;
- }
+ /* Find the normal taken edge and the normal fallthru edge.
- /* Find common ancestor scope. */
- if (bb1 && bb2)
- {
- scope s1 = REORDER_BLOCK_SCOPE (bb1);
- scope s2 = REORDER_BLOCK_SCOPE (bb2);
- while (s1 != s2)
- {
- if (! (s1 && s2))
- abort ();
- if (s1->level > s2->level)
- s1 = s1->outer;
- else if (s2->level > s1->level)
- s2 = s2->outer;
- else
- {
- s1 = s1->outer;
- s2 = s2->outer;
- }
- }
- com = s1;
- }
- else
- com = NULL;
+ Note, conditional jumps with other side effects may not
+ be fully optimized. In this case it is possible for
+ the conditional jump to branch to the same location as
+ the fallthru path.
- /* Close scopes. */
- if (bb1)
- {
- scope s = REORDER_BLOCK_SCOPE (bb1);
- ip = REORDER_BLOCK_EFF_END (bb1);
- while (s != com)
- {
- if (NOTE_BLOCK (s->note_beg))
- {
- ip = emit_note_after (NOTE_INSN_BLOCK_END, ip);
- NOTE_BLOCK (ip) = NOTE_BLOCK (s->note_end);
- }
- s = s->outer;
- }
- }
+ We should probably work to improve optimization of that
+ case; however, it seems silly not to also deal with such
+ problems here if they happen to occur. */
- /* Open scopes. */
- if (bb2)
- {
- scope s = REORDER_BLOCK_SCOPE (bb2);
- ip = bb2->head;
- while (s != com)
+ e_taken = e_fall = NULL;
+ for (e = bb->succ; e ; e = e->succ_next)
{
- if (NOTE_BLOCK (s->note_beg))
- {
- ip = emit_note_before (NOTE_INSN_BLOCK_BEG, ip);
- NOTE_BLOCK (ip) = NOTE_BLOCK (s->note_beg);
- }
- s = s->outer;
+ if (e->flags & EDGE_FALLTHRU)
+ e_fall = e;
+ else if (! (e->flags & EDGE_EH))
+ e_taken = e;
}
- }
-}
-
-/* Rebuild all the NOTE_INSN_BLOCK_BEG and NOTE_INSN_BLOCK_END notes based
- on the scope forest and the newly reordered basic blocks. */
-
-static void
-rebuild_scope_notes (forest)
- scope_forest_info *forest;
-{
- int i;
-
- if (forest->num_trees == 0)
- return;
-
- /* Start by opening the scopes before the first basic block. */
- insert_inter_bb_scope_notes (NULL, BASIC_BLOCK (0));
-
- /* Then, open and close scopes as needed between blocks. */
- for (i = 0; i < n_basic_blocks - 1; i++)
- {
- basic_block bb1 = BASIC_BLOCK (i);
- basic_block bb2 = BASIC_BLOCK (i + 1);
- if (REORDER_BLOCK_SCOPE (bb1) != REORDER_BLOCK_SCOPE (bb2))
- insert_inter_bb_scope_notes (bb1, bb2);
- insert_intra_bb_scope_notes (bb1);
+ next = (taken ? e_taken : e_fall)->dest;
}
- /* Finally, close the scopes after the last basic block. */
- insert_inter_bb_scope_notes (BASIC_BLOCK (n_basic_blocks - 1), NULL);
- insert_intra_bb_scope_notes (BASIC_BLOCK (n_basic_blocks - 1));
-}
-
-
-/* Free the storage associated with the scope tree at S. */
-
-static void
-free_scope_forest_1 (s)
- scope s;
-{
- scope p, next;
-
- for (p = s->inner; p; p = next)
+ /* In the absence of a prediction, disturb things as little as possible
+ by selecting the old "next" block from the list of successors. If
+ there had been a fallthru edge, that will be the one. */
+ if (! next)
{
- next = p->next;
- free_scope_forest_1 (p);
- }
-
- if (s->bbs)
- free (s->bbs);
- free (s);
-}
-
-
-/* Free the storage associated with the scope forest. */
-
-static void
-free_scope_forest (forest)
- scope_forest_info *forest;
-{
- int i;
- for (i = 0; i < forest->num_trees; i++)
- free_scope_forest_1 (forest->trees[i]);
-}
-
-
-/* Visualize the scope forest. */
-
-void
-dump_scope_forest (forest)
- scope_forest_info *forest;
-{
- if (forest->num_trees == 0)
- fprintf (stderr, "\n< Empty scope forest >\n");
- else
- {
- int i;
- fprintf (stderr, "\n< Scope forest >\n");
- for (i = 0; i < forest->num_trees; i++)
- dump_scope_forest_1 (forest->trees[i], 0);
+ for (e = bb->succ; e ; e = e->succ_next)
+ if (e->dest->index == bb->index + 1)
+ {
+ if ((e->flags & EDGE_FALLTHRU)
+ || (e->dest->succ
+ && ! (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH))))
+ next = e->dest;
+ break;
+ }
}
-}
+ /* Make sure we didn't select a silly next block. */
+ if (! next || next == EXIT_BLOCK_PTR || RBI (next)->visited)
+ next = NULL;
-/* Recursive portion of dump_scope_forest. */
-
-static void
-dump_scope_forest_1 (s, indent)
- scope s;
- int indent;
-{
- scope p;
- int i;
-
- if (s->bb_beg != NULL && s->bb_beg == s->bb_end
- && REORDER_BLOCK_SCOPE (s->bb_beg)
- && REORDER_BLOCK_SCOPE (s->bb_beg)->level + 1 == s->level)
+ /* Recurse on the successors. Unroll the last call, as the normal
+ case is exactly one or two edges, and we can tail recurse. */
+ for (e = bb->succ; e; e = e->succ_next)
+ if (e->dest != EXIT_BLOCK_PTR
+ && ! RBI (e->dest)->visited
+ && e->dest->succ
+ && ! (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH)))
+ {
+ if (next)
+ {
+ prev = make_reorder_chain_1 (next, prev);
+ next = RBI (e->dest)->visited ? NULL : e->dest;
+ }
+ else
+ next = e->dest;
+ }
+ if (next)
{
- fprintf (stderr, "%*s", indent, "");
- fprintf (stderr, "BB%d:\n", s->bb_beg->index);
+ bb = next;
+ goto restart;
}
- fprintf (stderr, "%*s", indent, "");
- fprintf (stderr, "{ level %d (block %p)\n", s->level,
- NOTE_BLOCK (s->note_beg));
-
- fprintf (stderr, "%*s%s", indent, "", "bbs:");
- for (i = 0; i < s->num_bbs; i++)
- fprintf (stderr, " %d", s->bbs[i]->index);
- fprintf (stderr, "\n");
-
- for (p = s->inner; p; p = p->next)
- dump_scope_forest_1 (p, indent + 2);
-
- fprintf (stderr, "%*s", indent, "");
- fprintf (stderr, "}\n");
+ return prev;
}
-
-/* Reorder basic blocks. */
+/* Reorder basic blocks. The main entry point to this file. */
void
reorder_basic_blocks ()
{
- int i, j;
- struct loops loops_info;
- int num_loops;
- scope_forest_info forest;
-
- if (profile_arc_flag)
- return;
-
if (n_basic_blocks <= 1)
return;
- /* Exception edges are not currently handled. */
- for (i = 0; i < n_basic_blocks; i++)
- {
- edge e;
-
- for (e = BASIC_BLOCK (i)->succ; e && ! (e->flags & EDGE_EH);
- e = e->succ_next)
- continue;
-
- if (e && (e->flags & EDGE_EH))
- return;
- }
-
- reorder_index = 0;
-
- /* Find natural loops using the CFG. */
- num_loops = flow_loops_find (&loops_info);
-
- /* Dump loop information. */
- flow_loops_dump (&loops_info, rtl_dump_file, 0);
-
- reorder_last_visited = BASIC_BLOCK (0);
-
- for (i = 0; i < n_basic_blocks; i++)
- {
- basic_block bbi = BASIC_BLOCK (i);
- bbi->aux = xcalloc (1, sizeof (struct reorder_block_def));
- *((struct reorder_block_def *)bbi->aux) = rbd_init;
- }
-
- build_scope_forest (&forest);
- remove_scope_notes ();
-
- for (i = 0; i < n_basic_blocks; i++)
- {
- basic_block bbi = BASIC_BLOCK (i);
- REORDER_BLOCK_EFF_END (bbi) = skip_insns_after_block (bbi);
- if (i == 0)
- REORDER_BLOCK_EFF_HEAD (bbi) = get_insns ();
- else
- {
- rtx prev_eff_end = REORDER_BLOCK_EFF_END (BASIC_BLOCK (i - 1));
- REORDER_BLOCK_EFF_HEAD (bbi) = NEXT_INSN (prev_eff_end);
- }
- }
-
- /* If we've not got epilogue in RTL, we must fallthru to the exit.
- Force the last block to be at the end. */
- /* ??? Some ABIs (e.g. MIPS) require the return insn to be at the
- end of the function for stack unwinding purposes. */
-
-#ifndef HAVE_epilogue
-#define HAVE_epilogue 0
-#endif
-
- if (! HAVE_epilogue)
- {
- basic_block last = BASIC_BLOCK (n_basic_blocks - 1);
- REORDER_BLOCK_INDEX (last) = n_basic_blocks - 1;
- REORDER_BLOCK_FLAGS (last) |= REORDER_BLOCK_VISITED;
- }
-
- make_reorder_chain (BASIC_BLOCK (0));
-
- fixup_reorder_chain ();
-
-#ifdef ENABLE_CHECKING
- verify_insn_chain ();
-#endif
-
- /* Put basic_block_info in new order. */
- for (i = 0; i < n_basic_blocks - 1; i++)
- {
- for (j = i; i != REORDER_BLOCK_INDEX (BASIC_BLOCK (j)); j++)
- continue;
-
- if (REORDER_BLOCK_INDEX (BASIC_BLOCK (j)) == i
- && i != j)
- {
- basic_block tempbb;
- int temprbi;
- int rbi = REORDER_BLOCK_INDEX (BASIC_BLOCK (j));
-
- temprbi = BASIC_BLOCK (rbi)->index;
- BASIC_BLOCK (rbi)->index = BASIC_BLOCK (j)->index;
- BASIC_BLOCK (j)->index = temprbi;
- tempbb = BASIC_BLOCK (rbi);
- BASIC_BLOCK (rbi) = BASIC_BLOCK (j);
- BASIC_BLOCK (j) = tempbb;
- }
- }
-
- rebuild_scope_notes (&forest);
- free_scope_forest (&forest);
- reorder_blocks ();
-
-#ifdef ENABLE_CHECKING
- verify_flow_info ();
-#endif
+ cfg_layout_initialize ();
- for (i = 0; i < n_basic_blocks; i++)
- free (BASIC_BLOCK (i)->aux);
+ make_reorder_chain ();
- /* Free loop information. */
- flow_loops_free (&loops_info);
+ if (rtl_dump_file)
+ dump_flow_info (rtl_dump_file);
+ cfg_layout_finalize ();
}
-
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