| /* Top-level control of tree optimizations. |
| Copyright 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010 |
| Free Software Foundation, Inc. |
| Contributed by Diego Novillo <dnovillo@redhat.com> |
| |
| 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 |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include "config.h" |
| #include "system.h" |
| #include "coretypes.h" |
| #include "tm.h" |
| #include "tree.h" |
| #include "tm_p.h" |
| #include "basic-block.h" |
| #include "output.h" |
| #include "flags.h" |
| #include "tree-flow.h" |
| #include "tree-dump.h" |
| #include "timevar.h" |
| #include "function.h" |
| #include "langhooks.h" |
| #include "diagnostic-core.h" |
| #include "toplev.h" |
| #include "flags.h" |
| #include "cgraph.h" |
| #include "tree-inline.h" |
| #include "tree-mudflap.h" |
| #include "tree-pass.h" |
| #include "ggc.h" |
| #include "cgraph.h" |
| #include "graph.h" |
| #include "cfgloop.h" |
| #include "except.h" |
| #include "plugin.h" |
| #include "regset.h" /* FIXME: For reg_obstack. */ |
| |
| /* Gate: execute, or not, all of the non-trivial optimizations. */ |
| |
| static bool |
| gate_all_optimizations (void) |
| { |
| return (optimize >= 1 |
| /* Don't bother doing anything if the program has errors. |
| We have to pass down the queue if we already went into SSA */ |
| && (!seen_error () || gimple_in_ssa_p (cfun))); |
| } |
| |
| struct gimple_opt_pass pass_all_optimizations = |
| { |
| { |
| GIMPLE_PASS, |
| "*all_optimizations", /* name */ |
| gate_all_optimizations, /* gate */ |
| NULL, /* execute */ |
| NULL, /* sub */ |
| NULL, /* next */ |
| 0, /* static_pass_number */ |
| TV_OPTIMIZE, /* tv_id */ |
| 0, /* properties_required */ |
| 0, /* properties_provided */ |
| 0, /* properties_destroyed */ |
| 0, /* todo_flags_start */ |
| 0 /* todo_flags_finish */ |
| } |
| }; |
| |
| /* Gate: execute, or not, all of the non-trivial optimizations. */ |
| |
| static bool |
| gate_all_early_local_passes (void) |
| { |
| /* Don't bother doing anything if the program has errors. */ |
| return (!seen_error () && !in_lto_p); |
| } |
| |
| static unsigned int |
| execute_all_early_local_passes (void) |
| { |
| /* Once this pass (and its sub-passes) are complete, all functions |
| will be in SSA form. Technically this state change is happening |
| a tad early, since the sub-passes have not yet run, but since |
| none of the sub-passes are IPA passes and do not create new |
| functions, this is ok. We're setting this value for the benefit |
| of IPA passes that follow. */ |
| if (cgraph_state < CGRAPH_STATE_IPA_SSA) |
| cgraph_state = CGRAPH_STATE_IPA_SSA; |
| return 0; |
| } |
| |
| struct simple_ipa_opt_pass pass_early_local_passes = |
| { |
| { |
| SIMPLE_IPA_PASS, |
| "early_local_cleanups", /* name */ |
| gate_all_early_local_passes, /* gate */ |
| execute_all_early_local_passes, /* execute */ |
| NULL, /* sub */ |
| NULL, /* next */ |
| 0, /* static_pass_number */ |
| TV_EARLY_LOCAL, /* tv_id */ |
| 0, /* properties_required */ |
| 0, /* properties_provided */ |
| 0, /* properties_destroyed */ |
| 0, /* todo_flags_start */ |
| TODO_remove_functions /* todo_flags_finish */ |
| } |
| }; |
| |
| /* Gate: execute, or not, all of the non-trivial optimizations. */ |
| |
| static bool |
| gate_all_early_optimizations (void) |
| { |
| return (optimize >= 1 |
| /* Don't bother doing anything if the program has errors. */ |
| && !seen_error ()); |
| } |
| |
| struct gimple_opt_pass pass_all_early_optimizations = |
| { |
| { |
| GIMPLE_PASS, |
| "early_optimizations", /* name */ |
| gate_all_early_optimizations, /* gate */ |
| NULL, /* execute */ |
| NULL, /* sub */ |
| NULL, /* next */ |
| 0, /* static_pass_number */ |
| TV_NONE, /* tv_id */ |
| 0, /* properties_required */ |
| 0, /* properties_provided */ |
| 0, /* properties_destroyed */ |
| 0, /* todo_flags_start */ |
| 0 /* todo_flags_finish */ |
| } |
| }; |
| |
| |
| /* Pass: cleanup the CFG just before expanding trees to RTL. |
| This is just a round of label cleanups and case node grouping |
| because after the tree optimizers have run such cleanups may |
| be necessary. */ |
| |
| static unsigned int |
| execute_cleanup_cfg_post_optimizing (void) |
| { |
| cleanup_tree_cfg (); |
| cleanup_dead_labels (); |
| group_case_labels (); |
| if ((flag_compare_debug_opt || flag_compare_debug) |
| && flag_dump_final_insns) |
| { |
| FILE *final_output = fopen (flag_dump_final_insns, "a"); |
| |
| if (!final_output) |
| { |
| error ("could not open final insn dump file %qs: %m", |
| flag_dump_final_insns); |
| flag_dump_final_insns = NULL; |
| } |
| else |
| { |
| int save_unnumbered = flag_dump_unnumbered; |
| int save_noaddr = flag_dump_noaddr; |
| |
| flag_dump_noaddr = flag_dump_unnumbered = 1; |
| fprintf (final_output, "\n"); |
| dump_enumerated_decls (final_output, dump_flags | TDF_NOUID); |
| flag_dump_noaddr = save_noaddr; |
| flag_dump_unnumbered = save_unnumbered; |
| if (fclose (final_output)) |
| { |
| error ("could not close final insn dump file %qs: %m", |
| flag_dump_final_insns); |
| flag_dump_final_insns = NULL; |
| } |
| } |
| } |
| return 0; |
| } |
| |
| struct gimple_opt_pass pass_cleanup_cfg_post_optimizing = |
| { |
| { |
| GIMPLE_PASS, |
| "optimized", /* name */ |
| NULL, /* gate */ |
| execute_cleanup_cfg_post_optimizing, /* execute */ |
| NULL, /* sub */ |
| NULL, /* next */ |
| 0, /* static_pass_number */ |
| TV_TREE_CLEANUP_CFG, /* tv_id */ |
| PROP_cfg, /* properties_required */ |
| 0, /* properties_provided */ |
| 0, /* properties_destroyed */ |
| 0, /* todo_flags_start */ |
| TODO_dump_func /* todo_flags_finish */ |
| | TODO_remove_unused_locals |
| } |
| }; |
| |
| /* Pass: do the actions required to finish with tree-ssa optimization |
| passes. */ |
| |
| unsigned int |
| execute_free_datastructures (void) |
| { |
| free_dominance_info (CDI_DOMINATORS); |
| free_dominance_info (CDI_POST_DOMINATORS); |
| |
| /* And get rid of annotations we no longer need. */ |
| delete_tree_cfg_annotations (); |
| |
| return 0; |
| } |
| |
| /* IPA passes, compilation of earlier functions or inlining |
| might have changed some properties, such as marked functions nothrow, |
| pure, const or noreturn. |
| Remove redundant edges and basic blocks, and create new ones if necessary. |
| |
| This pass can't be executed as stand alone pass from pass manager, because |
| in between inlining and this fixup the verify_flow_info would fail. */ |
| |
| unsigned int |
| execute_fixup_cfg (void) |
| { |
| basic_block bb; |
| gimple_stmt_iterator gsi; |
| int todo = gimple_in_ssa_p (cfun) ? TODO_verify_ssa : 0; |
| gcov_type count_scale; |
| edge e; |
| edge_iterator ei; |
| |
| if (ENTRY_BLOCK_PTR->count) |
| count_scale = (cgraph_node (current_function_decl)->count * REG_BR_PROB_BASE |
| + ENTRY_BLOCK_PTR->count / 2) / ENTRY_BLOCK_PTR->count; |
| else |
| count_scale = REG_BR_PROB_BASE; |
| |
| ENTRY_BLOCK_PTR->count = cgraph_node (current_function_decl)->count; |
| EXIT_BLOCK_PTR->count = (EXIT_BLOCK_PTR->count * count_scale |
| + REG_BR_PROB_BASE / 2) / REG_BR_PROB_BASE; |
| |
| FOR_EACH_BB (bb) |
| { |
| bb->count = (bb->count * count_scale |
| + REG_BR_PROB_BASE / 2) / REG_BR_PROB_BASE; |
| for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) |
| { |
| gimple stmt = gsi_stmt (gsi); |
| tree decl = is_gimple_call (stmt) |
| ? gimple_call_fndecl (stmt) |
| : NULL; |
| if (decl) |
| { |
| int flags = gimple_call_flags (stmt); |
| if (flags & (ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE)) |
| { |
| if (gimple_purge_dead_abnormal_call_edges (bb)) |
| todo |= TODO_cleanup_cfg; |
| |
| if (gimple_in_ssa_p (cfun)) |
| { |
| todo |= TODO_update_ssa | TODO_cleanup_cfg; |
| update_stmt (stmt); |
| } |
| } |
| |
| if (flags & ECF_NORETURN |
| && fixup_noreturn_call (stmt)) |
| todo |= TODO_cleanup_cfg; |
| } |
| |
| if (maybe_clean_eh_stmt (stmt) |
| && gimple_purge_dead_eh_edges (bb)) |
| todo |= TODO_cleanup_cfg; |
| } |
| |
| FOR_EACH_EDGE (e, ei, bb->succs) |
| e->count = (e->count * count_scale |
| + REG_BR_PROB_BASE / 2) / REG_BR_PROB_BASE; |
| } |
| if (count_scale != REG_BR_PROB_BASE) |
| compute_function_frequency (); |
| |
| /* We just processed all calls. */ |
| if (cfun->gimple_df) |
| { |
| VEC_free (gimple, gc, MODIFIED_NORETURN_CALLS (cfun)); |
| MODIFIED_NORETURN_CALLS (cfun) = NULL; |
| } |
| |
| /* Dump a textual representation of the flowgraph. */ |
| if (dump_file) |
| gimple_dump_cfg (dump_file, dump_flags); |
| |
| return todo; |
| } |
| |
| struct gimple_opt_pass pass_fixup_cfg = |
| { |
| { |
| GIMPLE_PASS, |
| "*free_cfg_annotations", /* name */ |
| NULL, /* gate */ |
| execute_fixup_cfg, /* execute */ |
| NULL, /* sub */ |
| NULL, /* next */ |
| 0, /* static_pass_number */ |
| TV_NONE, /* tv_id */ |
| PROP_cfg, /* properties_required */ |
| 0, /* properties_provided */ |
| 0, /* properties_destroyed */ |
| 0, /* todo_flags_start */ |
| 0 /* todo_flags_finish */ |
| } |
| }; |
| |
| /* Do the actions required to initialize internal data structures used |
| in tree-ssa optimization passes. */ |
| |
| static unsigned int |
| execute_init_datastructures (void) |
| { |
| /* Allocate hash tables, arrays and other structures. */ |
| init_tree_ssa (cfun); |
| return 0; |
| } |
| |
| struct gimple_opt_pass pass_init_datastructures = |
| { |
| { |
| GIMPLE_PASS, |
| "*init_datastructures", /* name */ |
| NULL, /* gate */ |
| execute_init_datastructures, /* execute */ |
| NULL, /* sub */ |
| NULL, /* next */ |
| 0, /* static_pass_number */ |
| TV_NONE, /* tv_id */ |
| PROP_cfg, /* properties_required */ |
| 0, /* properties_provided */ |
| 0, /* properties_destroyed */ |
| 0, /* todo_flags_start */ |
| 0 /* todo_flags_finish */ |
| } |
| }; |
| |
| void |
| tree_lowering_passes (tree fn) |
| { |
| tree saved_current_function_decl = current_function_decl; |
| |
| current_function_decl = fn; |
| push_cfun (DECL_STRUCT_FUNCTION (fn)); |
| gimple_register_cfg_hooks (); |
| bitmap_obstack_initialize (NULL); |
| execute_pass_list (all_lowering_passes); |
| if (optimize && cgraph_global_info_ready) |
| execute_pass_list (pass_early_local_passes.pass.sub); |
| free_dominance_info (CDI_POST_DOMINATORS); |
| free_dominance_info (CDI_DOMINATORS); |
| compact_blocks (); |
| current_function_decl = saved_current_function_decl; |
| bitmap_obstack_release (NULL); |
| pop_cfun (); |
| } |
| |
| /* For functions-as-trees languages, this performs all optimization and |
| compilation for FNDECL. */ |
| |
| void |
| tree_rest_of_compilation (tree fndecl) |
| { |
| location_t saved_loc; |
| |
| timevar_push (TV_REST_OF_COMPILATION); |
| |
| gcc_assert (cgraph_global_info_ready); |
| |
| /* Initialize the default bitmap obstack. */ |
| bitmap_obstack_initialize (NULL); |
| |
| /* Initialize the RTL code for the function. */ |
| current_function_decl = fndecl; |
| saved_loc = input_location; |
| input_location = DECL_SOURCE_LOCATION (fndecl); |
| init_function_start (fndecl); |
| |
| /* Even though we're inside a function body, we still don't want to |
| call expand_expr to calculate the size of a variable-sized array. |
| We haven't necessarily assigned RTL to all variables yet, so it's |
| not safe to try to expand expressions involving them. */ |
| cfun->dont_save_pending_sizes_p = 1; |
| |
| gimple_register_cfg_hooks (); |
| |
| bitmap_obstack_initialize (®_obstack); /* FIXME, only at RTL generation*/ |
| |
| execute_all_ipa_transforms (); |
| |
| /* Perform all tree transforms and optimizations. */ |
| |
| /* Signal the start of passes. */ |
| invoke_plugin_callbacks (PLUGIN_ALL_PASSES_START, NULL); |
| |
| execute_pass_list (all_passes); |
| |
| /* Signal the end of passes. */ |
| invoke_plugin_callbacks (PLUGIN_ALL_PASSES_END, NULL); |
| |
| bitmap_obstack_release (®_obstack); |
| |
| /* Release the default bitmap obstack. */ |
| bitmap_obstack_release (NULL); |
| |
| set_cfun (NULL); |
| |
| /* If requested, warn about function definitions where the function will |
| return a value (usually of some struct or union type) which itself will |
| take up a lot of stack space. */ |
| if (warn_larger_than && !DECL_EXTERNAL (fndecl) && TREE_TYPE (fndecl)) |
| { |
| tree ret_type = TREE_TYPE (TREE_TYPE (fndecl)); |
| |
| if (ret_type && TYPE_SIZE_UNIT (ret_type) |
| && TREE_CODE (TYPE_SIZE_UNIT (ret_type)) == INTEGER_CST |
| && 0 < compare_tree_int (TYPE_SIZE_UNIT (ret_type), |
| larger_than_size)) |
| { |
| unsigned int size_as_int |
| = TREE_INT_CST_LOW (TYPE_SIZE_UNIT (ret_type)); |
| |
| if (compare_tree_int (TYPE_SIZE_UNIT (ret_type), size_as_int) == 0) |
| warning (OPT_Wlarger_than_, "size of return value of %q+D is %u bytes", |
| fndecl, size_as_int); |
| else |
| warning (OPT_Wlarger_than_, "size of return value of %q+D is larger than %wd bytes", |
| fndecl, larger_than_size); |
| } |
| } |
| |
| gimple_set_body (fndecl, NULL); |
| if (DECL_STRUCT_FUNCTION (fndecl) == 0 |
| && !cgraph_node (fndecl)->origin) |
| { |
| /* Stop pointing to the local nodes about to be freed. |
| But DECL_INITIAL must remain nonzero so we know this |
| was an actual function definition. |
| For a nested function, this is done in c_pop_function_context. |
| If rest_of_compilation set this to 0, leave it 0. */ |
| if (DECL_INITIAL (fndecl) != 0) |
| DECL_INITIAL (fndecl) = error_mark_node; |
| } |
| |
| input_location = saved_loc; |
| |
| ggc_collect (); |
| timevar_pop (TV_REST_OF_COMPILATION); |
| } |