1 /* Hooks for cfg representation specific functions. 2 Copyright (C) 2003-2018 Free Software Foundation, Inc. 3 Contributed by Sebastian Pop <s.pop@laposte.net> 4 5 This file is part of GCC. 6 7 GCC is free software; you can redistribute it and/or modify 8 it under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 3, or (at your option) 10 any later version. 11 12 GCC is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 GNU General Public License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with GCC; see the file COPYING3. If not see 19 <http://www.gnu.org/licenses/>. */ 20 21 #ifndef GCC_CFGHOOKS_H 22 #define GCC_CFGHOOKS_H 23 24 #include "predict.h" 25 26 /* Structure to gather statistic about profile consistency, per pass. 27 An array of this structure, indexed by pass static number, is allocated 28 in passes.c. The structure is defined here so that different CFG modes 29 can do their book-keeping via CFG hooks. 30 31 For every field[2], field[0] is the count before the pass runs, and 32 field[1] is the post-pass count. This allows us to monitor the effect 33 of each individual pass on the profile consistency. 34 35 This structure is not supposed to be used by anything other than passes.c 36 and one CFG hook per CFG mode. */ 37 struct profile_record 38 { 39 /* The number of basic blocks where sum(freq) of the block's predecessors 40 doesn't match reasonably well with the incoming frequency. */ 41 int num_mismatched_freq_in[2]; 42 /* Likewise for a basic block's successors. */ 43 int num_mismatched_freq_out[2]; 44 /* The number of basic blocks where sum(count) of the block's predecessors 45 doesn't match reasonably well with the incoming frequency. */ 46 int num_mismatched_count_in[2]; 47 /* Likewise for a basic block's successors. */ 48 int num_mismatched_count_out[2]; 49 /* A weighted cost of the run-time of the function body. */ 50 gcov_type time[2]; 51 /* A weighted cost of the size of the function body. */ 52 int size[2]; 53 /* True iff this pass actually was run. */ 54 bool run; 55 }; 56 57 58 struct cfg_hooks 59 { 60 /* Name of the corresponding ir. */ 61 const char *name; 62 63 /* Debugging. */ 64 int (*verify_flow_info) (void); 65 void (*dump_bb) (FILE *, basic_block, int, dump_flags_t); 66 void (*dump_bb_for_graph) (pretty_printer *, basic_block); 67 68 /* Basic CFG manipulation. */ 69 70 /* Return new basic block. */ 71 basic_block (*create_basic_block) (void *head, void *end, basic_block after); 72 73 /* Redirect edge E to the given basic block B and update underlying program 74 representation. Returns edge representing redirected branch (that may not 75 be equivalent to E in the case of duplicate edges being removed) or NULL 76 if edge is not easily redirectable for whatever reason. */ 77 edge (*redirect_edge_and_branch) (edge e, basic_block b); 78 79 /* Same as the above but allows redirecting of fallthru edges. In that case 80 newly created forwarder basic block is returned. The edge must 81 not be abnormal. */ 82 basic_block (*redirect_edge_and_branch_force) (edge, basic_block); 83 84 /* Returns true if it is possible to remove the edge by redirecting it 85 to the destination of the other edge going from its source. */ 86 bool (*can_remove_branch_p) (const_edge); 87 88 /* Remove statements corresponding to a given basic block. */ 89 void (*delete_basic_block) (basic_block); 90 91 /* Creates a new basic block just after basic block B by splitting 92 everything after specified instruction I. */ 93 basic_block (*split_block) (basic_block b, void * i); 94 95 /* Move block B immediately after block A. */ 96 bool (*move_block_after) (basic_block b, basic_block a); 97 98 /* Return true when blocks A and B can be merged into single basic block. */ 99 bool (*can_merge_blocks_p) (basic_block a, basic_block b); 100 101 /* Merge blocks A and B. */ 102 void (*merge_blocks) (basic_block a, basic_block b); 103 104 /* Predict edge E using PREDICTOR to given PROBABILITY. */ 105 void (*predict_edge) (edge e, enum br_predictor predictor, int probability); 106 107 /* Return true if the one of outgoing edges is already predicted by 108 PREDICTOR. */ 109 bool (*predicted_by_p) (const_basic_block bb, enum br_predictor predictor); 110 111 /* Return true when block A can be duplicated. */ 112 bool (*can_duplicate_block_p) (const_basic_block a); 113 114 /* Duplicate block A. */ 115 basic_block (*duplicate_block) (basic_block a); 116 117 /* Higher level functions representable by primitive operations above if 118 we didn't have some oddities in RTL and Tree representations. */ 119 basic_block (*split_edge) (edge); 120 void (*make_forwarder_block) (edge); 121 122 /* Try to make the edge fallthru. */ 123 void (*tidy_fallthru_edge) (edge); 124 125 /* Make the edge non-fallthru. */ 126 basic_block (*force_nonfallthru) (edge); 127 128 /* Say whether a block ends with a call, possibly followed by some 129 other code that must stay with the call. */ 130 bool (*block_ends_with_call_p) (basic_block); 131 132 /* Say whether a block ends with a conditional branch. Switches 133 and unconditional branches do not qualify. */ 134 bool (*block_ends_with_condjump_p) (const_basic_block); 135 136 /* Add fake edges to the function exit for any non constant and non noreturn 137 calls, volatile inline assembly in the bitmap of blocks specified by 138 BLOCKS or to the whole CFG if BLOCKS is zero. Return the number of blocks 139 that were split. 140 141 The goal is to expose cases in which entering a basic block does not imply 142 that all subsequent instructions must be executed. */ 143 int (*flow_call_edges_add) (sbitmap); 144 145 /* This function is called immediately after edge E is added to the 146 edge vector E->dest->preds. */ 147 void (*execute_on_growing_pred) (edge); 148 149 /* This function is called immediately before edge E is removed from 150 the edge vector E->dest->preds. */ 151 void (*execute_on_shrinking_pred) (edge); 152 153 /* A hook for duplicating loop in CFG, currently this is used 154 in loop versioning. */ 155 bool (*cfg_hook_duplicate_loop_to_header_edge) (struct loop *, edge, 156 unsigned, sbitmap, 157 edge, vec<edge> *, 158 int); 159 160 /* Add condition to new basic block and update CFG used in loop 161 versioning. */ 162 void (*lv_add_condition_to_bb) (basic_block, basic_block, basic_block, 163 void *); 164 /* Update the PHI nodes in case of loop versioning. */ 165 void (*lv_adjust_loop_header_phi) (basic_block, basic_block, 166 basic_block, edge); 167 168 /* Given a condition BB extract the true/false taken/not taken edges 169 (depending if we are on tree's or RTL). */ 170 void (*extract_cond_bb_edges) (basic_block, edge *, edge *); 171 172 173 /* Add PHI arguments queued in PENDINT_STMT list on edge E to edge 174 E->dest (only in tree-ssa loop versioning. */ 175 void (*flush_pending_stmts) (edge); 176 177 /* True if a block contains no executable instructions. */ 178 bool (*empty_block_p) (basic_block); 179 180 /* Split a basic block if it ends with a conditional branch and if 181 the other part of the block is not empty. */ 182 basic_block (*split_block_before_cond_jump) (basic_block); 183 184 /* Do book-keeping of a basic block for the profile consistency checker. */ 185 void (*account_profile_record) (basic_block, int, struct profile_record *); 186 }; 187 188 extern void verify_flow_info (void); 189 190 /* Check control flow invariants, if internal consistency checks are 191 enabled. */ 192 193 static inline void 194 checking_verify_flow_info (void) 195 { 196 /* TODO: Add a separate option for -fchecking=cfg. */ 197 if (flag_checking) 198 verify_flow_info (); 199 } 200 201 extern void dump_bb (FILE *, basic_block, int, dump_flags_t); 202 extern void dump_bb_for_graph (pretty_printer *, basic_block); 203 extern void dump_flow_info (FILE *, dump_flags_t); 204 205 extern edge redirect_edge_and_branch (edge, basic_block); 206 extern basic_block redirect_edge_and_branch_force (edge, basic_block); 207 extern edge redirect_edge_succ_nodup (edge, basic_block); 208 extern bool can_remove_branch_p (const_edge); 209 extern void remove_branch (edge); 210 extern void remove_edge (edge); 211 extern edge split_block (basic_block, rtx); 212 extern edge split_block (basic_block, gimple *); 213 extern edge split_block_after_labels (basic_block); 214 extern bool move_block_after (basic_block, basic_block); 215 extern void delete_basic_block (basic_block); 216 extern basic_block split_edge (edge); 217 extern basic_block create_basic_block (rtx, rtx, basic_block); 218 extern basic_block create_basic_block (gimple_seq, basic_block); 219 extern basic_block create_empty_bb (basic_block); 220 extern bool can_merge_blocks_p (basic_block, basic_block); 221 extern void merge_blocks (basic_block, basic_block); 222 extern edge make_forwarder_block (basic_block, bool (*)(edge), 223 void (*) (basic_block)); 224 extern basic_block force_nonfallthru (edge); 225 extern void tidy_fallthru_edge (edge); 226 extern void tidy_fallthru_edges (void); 227 extern void predict_edge (edge e, enum br_predictor predictor, int probability); 228 extern bool predicted_by_p (const_basic_block bb, enum br_predictor predictor); 229 extern bool can_duplicate_block_p (const_basic_block); 230 extern basic_block duplicate_block (basic_block, edge, basic_block); 231 extern bool block_ends_with_call_p (basic_block bb); 232 extern bool empty_block_p (basic_block); 233 extern basic_block split_block_before_cond_jump (basic_block); 234 extern bool block_ends_with_condjump_p (const_basic_block bb); 235 extern int flow_call_edges_add (sbitmap); 236 extern void execute_on_growing_pred (edge); 237 extern void execute_on_shrinking_pred (edge); 238 extern bool cfg_hook_duplicate_loop_to_header_edge (struct loop *loop, edge, 239 unsigned int ndupl, 240 sbitmap wont_exit, 241 edge orig, 242 vec<edge> *to_remove, 243 int flags); 244 245 extern void lv_flush_pending_stmts (edge); 246 extern void extract_cond_bb_edges (basic_block, edge *, edge*); 247 extern void lv_adjust_loop_header_phi (basic_block, basic_block, basic_block, 248 edge); 249 extern void lv_add_condition_to_bb (basic_block, basic_block, basic_block, 250 void *); 251 252 extern bool can_copy_bbs_p (basic_block *, unsigned); 253 extern void copy_bbs (basic_block *, unsigned, basic_block *, 254 edge *, unsigned, edge *, struct loop *, 255 basic_block, bool); 256 257 void account_profile_record (struct profile_record *, int); 258 259 /* Hooks containers. */ 260 extern struct cfg_hooks gimple_cfg_hooks; 261 extern struct cfg_hooks rtl_cfg_hooks; 262 extern struct cfg_hooks cfg_layout_rtl_cfg_hooks; 263 264 /* Declarations. */ 265 extern enum ir_type current_ir_type (void); 266 extern void rtl_register_cfg_hooks (void); 267 extern void cfg_layout_rtl_register_cfg_hooks (void); 268 extern void gimple_register_cfg_hooks (void); 269 extern struct cfg_hooks get_cfg_hooks (void); 270 extern void set_cfg_hooks (struct cfg_hooks); 271 272 #endif /* GCC_CFGHOOKS_H */ 273