1 /* Hooks for cfg representation specific functions. 2 Copyright (C) 2003-2019 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; 42 /* Likewise for a basic block's successors. */ 43 int num_mismatched_freq_out; 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; 47 /* Likewise for a basic block's successors. */ 48 int num_mismatched_count_out; 49 /* A weighted cost of the run-time of the function body. */ 50 gcov_type_unsigned time; 51 /* A weighted cost of the size of the function body. */ 52 int size; 53 /* True iff this pass actually was run. */ 54 bool run; 55 }; 56 57 typedef int_hash <unsigned short, 0> dependence_hash; 58 59 /* Optional data for duplicate_block. */ 60 61 struct copy_bb_data 62 { 63 copy_bb_data() : dependence_map (NULL) {} 64 ~copy_bb_data () { delete dependence_map; } 65 66 /* A map from the copied BBs dependence info cliques to 67 equivalents in the BBs duplicated to. */ 68 hash_map<dependence_hash, unsigned short> *dependence_map; 69 }; 70 71 struct cfg_hooks 72 { 73 /* Name of the corresponding ir. */ 74 const char *name; 75 76 /* Debugging. */ 77 int (*verify_flow_info) (void); 78 void (*dump_bb) (FILE *, basic_block, int, dump_flags_t); 79 void (*dump_bb_for_graph) (pretty_printer *, basic_block); 80 81 /* Basic CFG manipulation. */ 82 83 /* Return new basic block. */ 84 basic_block (*create_basic_block) (void *head, void *end, basic_block after); 85 86 /* Redirect edge E to the given basic block B and update underlying program 87 representation. Returns edge representing redirected branch (that may not 88 be equivalent to E in the case of duplicate edges being removed) or NULL 89 if edge is not easily redirectable for whatever reason. */ 90 edge (*redirect_edge_and_branch) (edge e, basic_block b); 91 92 /* Same as the above but allows redirecting of fallthru edges. In that case 93 newly created forwarder basic block is returned. The edge must 94 not be abnormal. */ 95 basic_block (*redirect_edge_and_branch_force) (edge, basic_block); 96 97 /* Returns true if it is possible to remove the edge by redirecting it 98 to the destination of the other edge going from its source. */ 99 bool (*can_remove_branch_p) (const_edge); 100 101 /* Remove statements corresponding to a given basic block. */ 102 void (*delete_basic_block) (basic_block); 103 104 /* Creates a new basic block just after basic block B by splitting 105 everything after specified instruction I. */ 106 basic_block (*split_block) (basic_block b, void * i); 107 108 /* Move block B immediately after block A. */ 109 bool (*move_block_after) (basic_block b, basic_block a); 110 111 /* Return true when blocks A and B can be merged into single basic block. */ 112 bool (*can_merge_blocks_p) (basic_block a, basic_block b); 113 114 /* Merge blocks A and B. */ 115 void (*merge_blocks) (basic_block a, basic_block b); 116 117 /* Predict edge E using PREDICTOR to given PROBABILITY. */ 118 void (*predict_edge) (edge e, enum br_predictor predictor, int probability); 119 120 /* Return true if the one of outgoing edges is already predicted by 121 PREDICTOR. */ 122 bool (*predicted_by_p) (const_basic_block bb, enum br_predictor predictor); 123 124 /* Return true when block A can be duplicated. */ 125 bool (*can_duplicate_block_p) (const_basic_block a); 126 127 /* Duplicate block A. */ 128 basic_block (*duplicate_block) (basic_block a, copy_bb_data *); 129 130 /* Higher level functions representable by primitive operations above if 131 we didn't have some oddities in RTL and Tree representations. */ 132 basic_block (*split_edge) (edge); 133 void (*make_forwarder_block) (edge); 134 135 /* Try to make the edge fallthru. */ 136 void (*tidy_fallthru_edge) (edge); 137 138 /* Make the edge non-fallthru. */ 139 basic_block (*force_nonfallthru) (edge); 140 141 /* Say whether a block ends with a call, possibly followed by some 142 other code that must stay with the call. */ 143 bool (*block_ends_with_call_p) (basic_block); 144 145 /* Say whether a block ends with a conditional branch. Switches 146 and unconditional branches do not qualify. */ 147 bool (*block_ends_with_condjump_p) (const_basic_block); 148 149 /* Add fake edges to the function exit for any non constant and non noreturn 150 calls, volatile inline assembly in the bitmap of blocks specified by 151 BLOCKS or to the whole CFG if BLOCKS is zero. Return the number of blocks 152 that were split. 153 154 The goal is to expose cases in which entering a basic block does not imply 155 that all subsequent instructions must be executed. */ 156 int (*flow_call_edges_add) (sbitmap); 157 158 /* This function is called immediately after edge E is added to the 159 edge vector E->dest->preds. */ 160 void (*execute_on_growing_pred) (edge); 161 162 /* This function is called immediately before edge E is removed from 163 the edge vector E->dest->preds. */ 164 void (*execute_on_shrinking_pred) (edge); 165 166 /* A hook for duplicating loop in CFG, currently this is used 167 in loop versioning. */ 168 bool (*cfg_hook_duplicate_loop_to_header_edge) (struct loop *, edge, 169 unsigned, sbitmap, 170 edge, vec<edge> *, 171 int); 172 173 /* Add condition to new basic block and update CFG used in loop 174 versioning. */ 175 void (*lv_add_condition_to_bb) (basic_block, basic_block, basic_block, 176 void *); 177 /* Update the PHI nodes in case of loop versioning. */ 178 void (*lv_adjust_loop_header_phi) (basic_block, basic_block, 179 basic_block, edge); 180 181 /* Given a condition BB extract the true/false taken/not taken edges 182 (depending if we are on tree's or RTL). */ 183 void (*extract_cond_bb_edges) (basic_block, edge *, edge *); 184 185 186 /* Add PHI arguments queued in PENDINT_STMT list on edge E to edge 187 E->dest (only in tree-ssa loop versioning. */ 188 void (*flush_pending_stmts) (edge); 189 190 /* True if a block contains no executable instructions. */ 191 bool (*empty_block_p) (basic_block); 192 193 /* Split a basic block if it ends with a conditional branch and if 194 the other part of the block is not empty. */ 195 basic_block (*split_block_before_cond_jump) (basic_block); 196 197 /* Do book-keeping of a basic block for the profile consistency checker. */ 198 void (*account_profile_record) (basic_block, struct profile_record *); 199 }; 200 201 extern void verify_flow_info (void); 202 203 /* Check control flow invariants, if internal consistency checks are 204 enabled. */ 205 206 static inline void 207 checking_verify_flow_info (void) 208 { 209 /* TODO: Add a separate option for -fchecking=cfg. */ 210 if (flag_checking) 211 verify_flow_info (); 212 } 213 214 extern void dump_bb (FILE *, basic_block, int, dump_flags_t); 215 extern void dump_bb_for_graph (pretty_printer *, basic_block); 216 extern void dump_flow_info (FILE *, dump_flags_t); 217 218 extern edge redirect_edge_and_branch (edge, basic_block); 219 extern basic_block redirect_edge_and_branch_force (edge, basic_block); 220 extern edge redirect_edge_succ_nodup (edge, basic_block); 221 extern bool can_remove_branch_p (const_edge); 222 extern void remove_branch (edge); 223 extern void remove_edge (edge); 224 extern edge split_block (basic_block, rtx); 225 extern edge split_block (basic_block, gimple *); 226 extern edge split_block_after_labels (basic_block); 227 extern bool move_block_after (basic_block, basic_block); 228 extern void delete_basic_block (basic_block); 229 extern basic_block split_edge (edge); 230 extern basic_block create_basic_block (rtx, rtx, basic_block); 231 extern basic_block create_basic_block (gimple_seq, basic_block); 232 extern basic_block create_empty_bb (basic_block); 233 extern bool can_merge_blocks_p (basic_block, basic_block); 234 extern void merge_blocks (basic_block, basic_block); 235 extern edge make_forwarder_block (basic_block, bool (*)(edge), 236 void (*) (basic_block)); 237 extern basic_block force_nonfallthru (edge); 238 extern void tidy_fallthru_edge (edge); 239 extern void tidy_fallthru_edges (void); 240 extern void predict_edge (edge e, enum br_predictor predictor, int probability); 241 extern bool predicted_by_p (const_basic_block bb, enum br_predictor predictor); 242 extern bool can_duplicate_block_p (const_basic_block); 243 extern basic_block duplicate_block (basic_block, edge, basic_block, 244 copy_bb_data * = NULL); 245 extern bool block_ends_with_call_p (basic_block bb); 246 extern bool empty_block_p (basic_block); 247 extern basic_block split_block_before_cond_jump (basic_block); 248 extern bool block_ends_with_condjump_p (const_basic_block bb); 249 extern int flow_call_edges_add (sbitmap); 250 extern void execute_on_growing_pred (edge); 251 extern void execute_on_shrinking_pred (edge); 252 extern bool cfg_hook_duplicate_loop_to_header_edge (struct loop *loop, edge, 253 unsigned int ndupl, 254 sbitmap wont_exit, 255 edge orig, 256 vec<edge> *to_remove, 257 int flags); 258 259 extern void lv_flush_pending_stmts (edge); 260 extern void extract_cond_bb_edges (basic_block, edge *, edge*); 261 extern void lv_adjust_loop_header_phi (basic_block, basic_block, basic_block, 262 edge); 263 extern void lv_add_condition_to_bb (basic_block, basic_block, basic_block, 264 void *); 265 266 extern bool can_copy_bbs_p (basic_block *, unsigned); 267 extern void copy_bbs (basic_block *, unsigned, basic_block *, 268 edge *, unsigned, edge *, struct loop *, 269 basic_block, bool); 270 271 void profile_record_check_consistency (profile_record *); 272 void profile_record_account_profile (profile_record *); 273 274 /* Hooks containers. */ 275 extern struct cfg_hooks gimple_cfg_hooks; 276 extern struct cfg_hooks rtl_cfg_hooks; 277 extern struct cfg_hooks cfg_layout_rtl_cfg_hooks; 278 279 /* Declarations. */ 280 extern enum ir_type current_ir_type (void); 281 extern void rtl_register_cfg_hooks (void); 282 extern void cfg_layout_rtl_register_cfg_hooks (void); 283 extern void gimple_register_cfg_hooks (void); 284 extern struct cfg_hooks get_cfg_hooks (void); 285 extern void set_cfg_hooks (struct cfg_hooks); 286 287 #endif /* GCC_CFGHOOKS_H */ 288