X-Git-Url: https://oss.titaniummirror.com/gitweb/?a=blobdiff_plain;f=gcc%2Floop-init.c;fp=gcc%2Floop-init.c;h=a1a91639dc4c8c504d3f3fb65be26156d0f8a2e8;hb=6fed43773c9b0ce596dca5686f37ac3fc0fa11c0;hp=0000000000000000000000000000000000000000;hpb=27b11d56b743098deb193d510b337ba22dc52e5c;p=msp430-gcc.git diff --git a/gcc/loop-init.c b/gcc/loop-init.c new file mode 100644 index 00000000..a1a91639 --- /dev/null +++ b/gcc/loop-init.c @@ -0,0 +1,402 @@ +/* Loop optimizer initialization routines and RTL loop optimization passes. + Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008 + 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 3, 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 COPYING3. If not see +. */ + +#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" +#include "df.h" +#include "ggc.h" + + +/* Initialize loop structures. This is used by the tree and RTL loop + optimizers. FLAGS specify what properties to compute and/or ensure for + loops. */ + +void +loop_optimizer_init (unsigned flags) +{ + struct loops *loops; + + gcc_assert (!current_loops); + loops = GGC_CNEW (struct loops); + + /* Find the loops. */ + + flow_loops_find (loops); + current_loops = loops; + + if (flags & LOOPS_MAY_HAVE_MULTIPLE_LATCHES) + { + /* If the loops may have multiple latches, we cannot canonicalize + them further (and most of the loop manipulation functions will + not work). However, we avoid modifying cfg, which some + passes may want. */ + gcc_assert ((flags & ~(LOOPS_MAY_HAVE_MULTIPLE_LATCHES + | LOOPS_HAVE_RECORDED_EXITS)) == 0); + loops_state_set (LOOPS_MAY_HAVE_MULTIPLE_LATCHES); + } + else + disambiguate_loops_with_multiple_latches (); + + /* Create pre-headers. */ + if (flags & LOOPS_HAVE_PREHEADERS) + { + int cp_flags = CP_SIMPLE_PREHEADERS; + + if (flags & LOOPS_HAVE_FALLTHRU_PREHEADERS) + cp_flags |= CP_FALLTHRU_PREHEADERS; + + create_preheaders (cp_flags); + } + + /* Force all latches to have only single successor. */ + if (flags & LOOPS_HAVE_SIMPLE_LATCHES) + force_single_succ_latches (); + + /* Mark irreducible loops. */ + if (flags & LOOPS_HAVE_MARKED_IRREDUCIBLE_REGIONS) + mark_irreducible_loops (); + + if (flags & LOOPS_HAVE_RECORDED_EXITS) + record_loop_exits (); + + /* Dump loops. */ + flow_loops_dump (dump_file, NULL, 1); + +#ifdef ENABLE_CHECKING + verify_dominators (CDI_DOMINATORS); + verify_loop_structure (); +#endif +} + +/* Finalize loop structures. */ + +void +loop_optimizer_finalize (void) +{ + loop_iterator li; + struct loop *loop; + basic_block bb; + + gcc_assert (current_loops != NULL); + + FOR_EACH_LOOP (li, loop, 0) + { + free_simple_loop_desc (loop); + } + + /* Clean up. */ + if (loops_state_satisfies_p (LOOPS_HAVE_RECORDED_EXITS)) + release_recorded_exits (); + flow_loops_free (current_loops); + ggc_free (current_loops); + current_loops = NULL; + + FOR_ALL_BB (bb) + { + bb->loop_father = NULL; + } + + /* Checking. */ +#ifdef ENABLE_CHECKING + /* FIXME: no point to verify flow info after bundling on ia64. Use this + hack for achieving this. */ + if (!reload_completed) + 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 rtl_opt_pass pass_loop2 = +{ + { + RTL_PASS, + "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 */ + } +}; + + +/* Initialization of the RTL loop passes. */ +static unsigned int +rtl_loop_init (void) +{ + gcc_assert (current_ir_type () == IR_RTL_CFGLAYOUT); + + if (dump_file) + dump_flow_info (dump_file, dump_flags); + + loop_optimizer_init (LOOPS_NORMAL); + return 0; +} + +struct rtl_opt_pass pass_rtl_loop_init = +{ + { + RTL_PASS, + "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_verify_rtl_sharing /* todo_flags_finish */ + } +}; + + +/* Finalization of the RTL loop passes. */ + +static unsigned int +rtl_loop_done (void) +{ + loop_optimizer_finalize (); + free_dominance_info (CDI_DOMINATORS); + + cleanup_cfg (0); + if (dump_file) + dump_flow_info (dump_file, dump_flags); + + return 0; +} + +struct rtl_opt_pass pass_rtl_loop_done = +{ + { + RTL_PASS, + "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_verify_rtl_sharing /* todo_flags_finish */ + } +}; + + +/* 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 (number_of_loops () > 1) + move_loop_invariants (); + return 0; +} + +struct rtl_opt_pass pass_rtl_move_loop_invariants = +{ + { + RTL_PASS, + "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_df_verify | + TODO_df_finish | TODO_verify_rtl_sharing | + TODO_dump_func /* todo_flags_finish */ + } +}; + + +/* Loop unswitching for RTL. */ +static bool +gate_rtl_unswitch (void) +{ + return flag_unswitch_loops; +} + +static unsigned int +rtl_unswitch (void) +{ + if (number_of_loops () > 1) + unswitch_loops (); + return 0; +} + +struct rtl_opt_pass pass_rtl_unswitch = +{ + { + RTL_PASS, + "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_verify_rtl_sharing, /* todo_flags_finish */ + } +}; + + +/* 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 (number_of_loops () > 1) + { + int flags = 0; + if (dump_file) + df_dump (dump_file); + + 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 (flags); + } + return 0; +} + +struct rtl_opt_pass pass_rtl_unroll_and_peel_loops = +{ + { + RTL_PASS, + "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_verify_rtl_sharing, /* todo_flags_finish */ + } +}; + + +/* 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 (number_of_loops () > 1) + doloop_optimize_loops (); +#endif + return 0; +} + +struct rtl_opt_pass pass_rtl_doloop = +{ + { + RTL_PASS, + "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_verify_rtl_sharing /* todo_flags_finish */ + } +}; +