116 lines
2.8 KiB
C
116 lines
2.8 KiB
C
/* Loop optimizer initialization routines.
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Copyright (C) 2002, 2003 Free Software Foundation, Inc.
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This file is part of GCC.
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GCC is free software; you can redistribute it and/or modify it under
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the terms of the GNU General Public License as published by the Free
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Software Foundation; either version 2, or (at your option) any later
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version.
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GCC is distributed in the hope that it will be useful, but WITHOUT ANY
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WARRANTY; without even the implied warranty of MERCHANTABILITY or
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FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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for more details.
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You should have received a copy of the GNU General Public License
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along with GCC; see the file COPYING. If not, write to the Free
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Software Foundation, 59 Temple Place - Suite 330, Boston, MA
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02111-1307, USA. */
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#include "config.h"
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#include "system.h"
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#include "coretypes.h"
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#include "tm.h"
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#include "rtl.h"
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#include "hard-reg-set.h"
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#include "basic-block.h"
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#include "cfgloop.h"
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#include "cfglayout.h"
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#include "profile.h"
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/* Initialize loop optimizer. */
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struct loops *
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loop_optimizer_init (dumpfile)
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FILE *dumpfile;
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{
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struct loops *loops = xcalloc (1, sizeof (struct loops));
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edge e;
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/* Avoid annoying special cases of edges going to exit
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block. */
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for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
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if ((e->flags & EDGE_FALLTHRU) && e->src->succ->succ_next)
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split_edge (e);
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/* Find the loops. */
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if (flow_loops_find (loops, LOOP_TREE) <= 1)
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{
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/* No loops. */
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flow_loops_free (loops);
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free (loops);
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return NULL;
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}
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/* Not going to update these. */
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free (loops->cfg.rc_order);
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loops->cfg.rc_order = NULL;
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free (loops->cfg.dfs_order);
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loops->cfg.dfs_order = NULL;
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/* Initialize structures for layout changes. */
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cfg_layout_initialize (loops);
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/* Create pre-headers. */
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create_preheaders (loops, CP_SIMPLE_PREHEADERS | CP_INSIDE_CFGLAYOUT);
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/* Force all latches to have only single successor. */
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force_single_succ_latches (loops);
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/* Mark irreducible loops. */
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mark_irreducible_loops (loops);
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/* Dump loops. */
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flow_loops_dump (loops, dumpfile, NULL, 1);
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#ifdef ENABLE_CHECKING
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verify_dominators (loops->cfg.dom);
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verify_loop_structure (loops);
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#endif
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return loops;
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}
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/* Finalize loop optimizer. */
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void
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loop_optimizer_finalize (loops, dumpfile)
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struct loops *loops;
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FILE *dumpfile;
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{
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basic_block bb;
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/* Finalize layout changes. */
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/* Make chain. */
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FOR_EACH_BB (bb)
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if (bb->next_bb != EXIT_BLOCK_PTR)
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RBI (bb)->next = bb->next_bb;
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/* Another dump. */
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flow_loops_dump (loops, dumpfile, NULL, 1);
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/* Clean up. */
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flow_loops_free (loops);
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free (loops);
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/* Finalize changes. */
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cfg_layout_finalize ();
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/* Checking. */
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#ifdef ENABLE_CHECKING
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verify_flow_info ();
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#endif
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}
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