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diff --git a/gcc-4.2.1-5666.3/gcc/loop-init.c b/gcc-4.2.1-5666.3/gcc/loop-init.c
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+/* Loop optimizer initialization routines and RTL loop optimization passes.
+ Copyright (C) 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+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.
+
+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 GCC; see the file COPYING. If not, write to the Free
+Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301, USA. */
+
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include "tm.h"
+#include "rtl.h"
+#include "hard-reg-set.h"
+#include "obstack.h"
+#include "basic-block.h"
+#include "cfgloop.h"
+#include "cfglayout.h"
+#include "tree-pass.h"
+#include "timevar.h"
+#include "flags.h"
+
+
+/* Initialize loop optimizer. This is used by the tree and RTL loop
+ optimizers. FLAGS specify what properties to compute and/or ensure for
+ loops. */
+
+struct loops *
+loop_optimizer_init (unsigned flags)
+{
+ struct loops *loops = XCNEW (struct loops);
+ edge e;
+ edge_iterator ei;
+ static bool first_time = true;
+
+ if (first_time)
+ {
+ first_time = false;
+ init_set_costs ();
+ }
+
+ /* Avoid annoying special cases of edges going to exit
+ block. */
+
+ for (ei = ei_start (EXIT_BLOCK_PTR->preds); (e = ei_safe_edge (ei)); )
+ if ((e->flags & EDGE_FALLTHRU) && !single_succ_p (e->src))
+ split_edge (e);
+ else
+ ei_next (&ei);
+
+ /* Find the loops. */
+
+ if (flow_loops_find (loops) <= 1)
+ {
+ /* No loops. */
+ flow_loops_free (loops);
+ free (loops);
+
+ return NULL;
+ }
+
+ /* Not going to update these. */
+ free (loops->cfg.rc_order);
+ loops->cfg.rc_order = NULL;
+ free (loops->cfg.dfs_order);
+ loops->cfg.dfs_order = NULL;
+
+ /* Create pre-headers. */
+ if (flags & LOOPS_HAVE_PREHEADERS)
+ create_preheaders (loops, CP_SIMPLE_PREHEADERS);
+
+ /* Force all latches to have only single successor. */
+ if (flags & LOOPS_HAVE_SIMPLE_LATCHES)
+ force_single_succ_latches (loops);
+
+ /* Mark irreducible loops. */
+ if (flags & LOOPS_HAVE_MARKED_IRREDUCIBLE_REGIONS)
+ mark_irreducible_loops (loops);
+
+ if (flags & LOOPS_HAVE_MARKED_SINGLE_EXITS)
+ mark_single_exit_loops (loops);
+
+ /* Dump loops. */
+ flow_loops_dump (loops, dump_file, NULL, 1);
+
+#ifdef ENABLE_CHECKING
+ verify_dominators (CDI_DOMINATORS);
+ verify_loop_structure (loops);
+#endif
+
+ return loops;
+}
+
+/* Finalize loop optimizer. */
+void
+loop_optimizer_finalize (struct loops *loops)
+{
+ unsigned i;
+
+ if (!loops)
+ return;
+
+ for (i = 1; i < loops->num; i++)
+ if (loops->parray[i])
+ free_simple_loop_desc (loops->parray[i]);
+
+ /* Clean up. */
+ flow_loops_free (loops);
+ free (loops);
+
+ /* Checking. */
+#ifdef ENABLE_CHECKING
+ verify_flow_info ();
+#endif
+}
+
+
+/* Gate for the RTL loop superpass. The actual passes are subpasses.
+ See passes.c for more on that. */
+
+static bool
+gate_handle_loop2 (void)
+{
+ return (optimize > 0
+ && (flag_move_loop_invariants
+ || flag_unswitch_loops
+ || flag_peel_loops
+ || flag_unroll_loops
+#ifdef HAVE_doloop_end
+ || (flag_branch_on_count_reg && HAVE_doloop_end)
+#endif
+ ));
+}
+
+struct tree_opt_pass pass_loop2 =
+{
+ "loop2", /* name */
+ gate_handle_loop2, /* gate */
+ NULL, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_LOOP, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ TODO_dump_func |
+ TODO_ggc_collect, /* todo_flags_finish */
+ 'L' /* letter */
+};
+
+
+/* Initialization of the RTL loop passes. */
+static unsigned int
+rtl_loop_init (void)
+{
+ if (dump_file)
+ dump_flow_info (dump_file, dump_flags);
+
+ /* Initialize structures for layout changes. */
+ cfg_layout_initialize (0);
+
+ current_loops = loop_optimizer_init (LOOPS_NORMAL);
+ return 0;
+}
+
+struct tree_opt_pass pass_rtl_loop_init =
+{
+ "loop2_init", /* name */
+ NULL, /* gate */
+ rtl_loop_init, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_LOOP, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ TODO_dump_func, /* todo_flags_finish */
+ 'L' /* letter */
+};
+
+
+/* Finalization of the RTL loop passes. */
+static unsigned int
+rtl_loop_done (void)
+{
+ basic_block bb;
+
+ if (current_loops)
+ loop_optimizer_finalize (current_loops);
+
+ free_dominance_info (CDI_DOMINATORS);
+
+ /* Finalize layout changes. */
+ FOR_EACH_BB (bb)
+ if (bb->next_bb != EXIT_BLOCK_PTR)
+ bb->aux = bb->next_bb;
+ cfg_layout_finalize ();
+
+ cleanup_cfg (CLEANUP_EXPENSIVE);
+ delete_trivially_dead_insns (get_insns (), max_reg_num ());
+ reg_scan (get_insns (), max_reg_num ());
+ if (dump_file)
+ dump_flow_info (dump_file, dump_flags);
+
+ current_loops = NULL;
+ return 0;
+}
+
+struct tree_opt_pass pass_rtl_loop_done =
+{
+ "loop2_done", /* name */
+ NULL, /* gate */
+ rtl_loop_done, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_LOOP, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ TODO_dump_func, /* todo_flags_finish */
+ 'L' /* letter */
+};
+
+
+/* Loop invariant code motion. */
+static bool
+gate_rtl_move_loop_invariants (void)
+{
+ return flag_move_loop_invariants;
+}
+
+static unsigned int
+rtl_move_loop_invariants (void)
+{
+ if (current_loops)
+ move_loop_invariants (current_loops);
+ return 0;
+}
+
+struct tree_opt_pass pass_rtl_move_loop_invariants =
+{
+ "loop2_invariant", /* name */
+ gate_rtl_move_loop_invariants, /* gate */
+ rtl_move_loop_invariants, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_LOOP, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ TODO_dump_func, /* todo_flags_finish */
+ 'L' /* letter */
+};
+
+
+/* Loop unswitching for RTL. */
+static bool
+gate_rtl_unswitch (void)
+{
+ return flag_unswitch_loops;
+}
+
+static unsigned int
+rtl_unswitch (void)
+{
+ if (current_loops)
+ unswitch_loops (current_loops);
+ return 0;
+}
+
+struct tree_opt_pass pass_rtl_unswitch =
+{
+ "loop2_unswitch", /* name */
+ gate_rtl_unswitch, /* gate */
+ rtl_unswitch, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_LOOP, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ TODO_dump_func, /* todo_flags_finish */
+ 'L' /* letter */
+};
+
+
+/* Loop unswitching for RTL. */
+static bool
+gate_rtl_unroll_and_peel_loops (void)
+{
+ return (flag_peel_loops || flag_unroll_loops || flag_unroll_all_loops);
+}
+
+static unsigned int
+rtl_unroll_and_peel_loops (void)
+{
+ if (current_loops)
+ {
+ int flags = 0;
+
+ if (flag_peel_loops)
+ flags |= UAP_PEEL;
+ if (flag_unroll_loops)
+ flags |= UAP_UNROLL;
+ if (flag_unroll_all_loops)
+ flags |= UAP_UNROLL_ALL;
+
+ unroll_and_peel_loops (current_loops, flags);
+ }
+ return 0;
+}
+
+struct tree_opt_pass pass_rtl_unroll_and_peel_loops =
+{
+ "loop2_unroll", /* name */
+ gate_rtl_unroll_and_peel_loops, /* gate */
+ rtl_unroll_and_peel_loops, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_LOOP, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ TODO_dump_func, /* todo_flags_finish */
+ 'L' /* letter */
+};
+
+
+/* The doloop optimization. */
+static bool
+gate_rtl_doloop (void)
+{
+#ifdef HAVE_doloop_end
+ return (flag_branch_on_count_reg && HAVE_doloop_end);
+#else
+ return 0;
+#endif
+}
+
+static unsigned int
+rtl_doloop (void)
+{
+#ifdef HAVE_doloop_end
+ if (current_loops)
+ doloop_optimize_loops (current_loops);
+#endif
+ return 0;
+}
+
+struct tree_opt_pass pass_rtl_doloop =
+{
+ "loop2_doloop", /* name */
+ gate_rtl_doloop, /* gate */
+ rtl_doloop, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_LOOP, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ TODO_dump_func, /* todo_flags_finish */
+ 'L' /* letter */
+};
+