/* Single entry single exit control flow regions. Copyright (C) 2008-2014 Free Software Foundation, Inc. Contributed by Jan Sjodin and Sebastian Pop . 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 . */ #ifndef GCC_SESE_H #define GCC_SESE_H /* A Single Entry, Single Exit region is a part of the CFG delimited by two edges. */ typedef struct sese_s { /* Single ENTRY and single EXIT from the SESE region. */ edge entry, exit; /* Parameters used within the SCOP. */ vec params; /* Loops completely contained in the SCOP. */ bitmap loops; vec loop_nest; /* Are we allowed to add more params? This is for debugging purpose. We can only add new params before generating the bb domains, otherwise they become invalid. */ bool add_params; } *sese; #define SESE_ENTRY(S) (S->entry) #define SESE_ENTRY_BB(S) (S->entry->dest) #define SESE_EXIT(S) (S->exit) #define SESE_EXIT_BB(S) (S->exit->dest) #define SESE_PARAMS(S) (S->params) #define SESE_LOOPS(S) (S->loops) #define SESE_LOOP_NEST(S) (S->loop_nest) #define SESE_ADD_PARAMS(S) (S->add_params) extern sese new_sese (edge, edge); extern void free_sese (sese); extern void sese_insert_phis_for_liveouts (sese, basic_block, edge, edge); extern void build_sese_loop_nests (sese); extern edge copy_bb_and_scalar_dependences (basic_block, sese, edge, vec , bool *); extern struct loop *outermost_loop_in_sese (sese, basic_block); extern tree scalar_evolution_in_region (sese, loop_p, tree); /* Check that SESE contains LOOP. */ static inline bool sese_contains_loop (sese sese, struct loop *loop) { return bitmap_bit_p (SESE_LOOPS (sese), loop->num); } /* The number of parameters in REGION. */ static inline unsigned sese_nb_params (sese region) { return SESE_PARAMS (region).length (); } /* Checks whether BB is contained in the region delimited by ENTRY and EXIT blocks. */ static inline bool bb_in_region (basic_block bb, basic_block entry, basic_block exit) { #ifdef ENABLE_CHECKING { edge e; edge_iterator ei; /* Check that there are no edges coming in the region: all the predecessors of EXIT are dominated by ENTRY. */ FOR_EACH_EDGE (e, ei, exit->preds) dominated_by_p (CDI_DOMINATORS, e->src, entry); } #endif return dominated_by_p (CDI_DOMINATORS, bb, entry) && !(dominated_by_p (CDI_DOMINATORS, bb, exit) && !dominated_by_p (CDI_DOMINATORS, entry, exit)); } /* Checks whether BB is contained in the region delimited by ENTRY and EXIT blocks. */ static inline bool bb_in_sese_p (basic_block bb, sese region) { basic_block entry = SESE_ENTRY_BB (region); basic_block exit = SESE_EXIT_BB (region); return bb_in_region (bb, entry, exit); } /* Returns true when STMT is defined in REGION. */ static inline bool stmt_in_sese_p (gimple stmt, sese region) { basic_block bb = gimple_bb (stmt); return bb && bb_in_sese_p (bb, region); } /* Returns true when NAME is defined in REGION. */ static inline bool defined_in_sese_p (tree name, sese region) { gimple stmt = SSA_NAME_DEF_STMT (name); return stmt_in_sese_p (stmt, region); } /* Returns true when LOOP is in REGION. */ static inline bool loop_in_sese_p (struct loop *loop, sese region) { return (bb_in_sese_p (loop->header, region) && bb_in_sese_p (loop->latch, region)); } /* Returns the loop depth of LOOP in REGION. The loop depth is the same as the normal loop depth, but limited by a region. Example: loop_0 loop_1 { S0 <- region start S1 loop_2 S2 S3 <- region end } loop_0 does not exist in the region -> invalid loop_1 exists, but is not completely contained in the region -> depth 0 loop_2 is completely contained -> depth 1 */ static inline unsigned int sese_loop_depth (sese region, loop_p loop) { unsigned int depth = 0; gcc_assert ((!loop_in_sese_p (loop, region) && (SESE_ENTRY_BB (region)->loop_father == loop || SESE_EXIT (region)->src->loop_father == loop)) || loop_in_sese_p (loop, region)); while (loop_in_sese_p (loop, region)) { depth++; loop = loop_outer (loop); } return depth; } /* Splits BB to make a single entry single exit region. */ static inline sese split_region_for_bb (basic_block bb) { edge entry, exit; if (single_pred_p (bb)) entry = single_pred_edge (bb); else { entry = split_block_after_labels (bb); bb = single_succ (bb); } if (single_succ_p (bb)) exit = single_succ_edge (bb); else { gimple_stmt_iterator gsi = gsi_last_bb (bb); gsi_prev (&gsi); exit = split_block (bb, gsi_stmt (gsi)); } return new_sese (entry, exit); } /* Returns the block preceding the entry of a SESE. */ static inline basic_block block_before_sese (sese sese) { return SESE_ENTRY (sese)->src; } /* A single entry single exit specialized for conditions. */ typedef struct ifsese_s { sese region; sese true_region; sese false_region; } *ifsese; extern void if_region_set_false_region (ifsese, sese); extern ifsese move_sese_in_condition (sese); extern edge get_true_edge_from_guard_bb (basic_block); extern edge get_false_edge_from_guard_bb (basic_block); extern void set_ifsese_condition (ifsese, tree); static inline edge if_region_entry (ifsese if_region) { return SESE_ENTRY (if_region->region); } static inline edge if_region_exit (ifsese if_region) { return SESE_EXIT (if_region->region); } static inline basic_block if_region_get_condition_block (ifsese if_region) { return if_region_entry (if_region)->dest; } /* Structure containing the mapping between the old names and the new names used after block copy in the new loop context. */ typedef struct rename_map_elt_s { tree old_name, expr; } *rename_map_elt; extern hashval_t rename_map_elt_info (const void *); extern int eq_rename_map_elts (const void *, const void *); /* Constructs a new SCEV_INFO_STR structure for VAR and INSTANTIATED_BELOW. */ static inline rename_map_elt new_rename_map_elt (tree old_name, tree expr) { rename_map_elt res; res = XNEW (struct rename_map_elt_s); res->old_name = old_name; res->expr = expr; return res; } /* Free and compute again all the dominators information. */ static inline void recompute_all_dominators (void) { mark_irreducible_loops (); free_dominance_info (CDI_DOMINATORS); calculate_dominance_info (CDI_DOMINATORS); } typedef struct gimple_bb { basic_block bb; struct poly_bb *pbb; /* Lists containing the restrictions of the conditional statements dominating this bb. This bb can only be executed, if all conditions are true. Example: for (i = 0; i <= 20; i++) { A if (2i <= 8) B } So for B there is an additional condition (2i <= 8). List of COND_EXPR and SWITCH_EXPR. A COND_EXPR is true only if the corresponding element in CONDITION_CASES is not NULL_TREE. For a SWITCH_EXPR the corresponding element in CONDITION_CASES is a CASE_LABEL_EXPR. */ vec conditions; vec condition_cases; vec data_refs; } *gimple_bb_p; #define GBB_BB(GBB) (GBB)->bb #define GBB_PBB(GBB) (GBB)->pbb #define GBB_DATA_REFS(GBB) (GBB)->data_refs #define GBB_CONDITIONS(GBB) (GBB)->conditions #define GBB_CONDITION_CASES(GBB) (GBB)->condition_cases /* Return the innermost loop that contains the basic block GBB. */ static inline struct loop * gbb_loop (struct gimple_bb *gbb) { return GBB_BB (gbb)->loop_father; } /* Returns the gimple loop, that corresponds to the loop_iterator_INDEX. If there is no corresponding gimple loop, we return NULL. */ static inline loop_p gbb_loop_at_index (gimple_bb_p gbb, sese region, int index) { loop_p loop = gbb_loop (gbb); int depth = sese_loop_depth (region, loop); while (--depth > index) loop = loop_outer (loop); gcc_assert (sese_contains_loop (region, loop)); return loop; } /* The number of common loops in REGION for GBB1 and GBB2. */ static inline int nb_common_loops (sese region, gimple_bb_p gbb1, gimple_bb_p gbb2) { loop_p l1 = gbb_loop (gbb1); loop_p l2 = gbb_loop (gbb2); loop_p common = find_common_loop (l1, l2); return sese_loop_depth (region, common); } /* Return true when DEF can be analyzed in REGION by the scalar evolution analyzer. */ static inline bool scev_analyzable_p (tree def, sese region) { loop_p loop; tree scev; tree type = TREE_TYPE (def); /* When Graphite generates code for a scev, the code generator expresses the scev in function of a single induction variable. This is unsafe for floating point computations, as it may replace a floating point sum reduction with a multiplication. The following test returns false for non integer types to avoid such problems. */ if (!INTEGRAL_TYPE_P (type) && !POINTER_TYPE_P (type)) return false; loop = loop_containing_stmt (SSA_NAME_DEF_STMT (def)); scev = scalar_evolution_in_region (region, loop, def); return !chrec_contains_undetermined (scev) && (TREE_CODE (scev) != SSA_NAME || !defined_in_sese_p (scev, region)) && (tree_does_not_contain_chrecs (scev) || evolution_function_is_affine_p (scev)); } #endif