gcc/cfghooks.h

   1 /* Hooks for cfg representation specific functions.
   2    Copyright (C) 2003, 2004, 2005, 2007 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 struct cfg_hooks
  25 {
  26   /* Name of the corresponding ir.  */
  27   const char *name;
  28
  29   /* Debugging.  */
  30   int (*verify_flow_info) (void);
  31   void (*dump_bb) (basic_block, FILE *, int);
  32
  33   /* Basic CFG manipulation.  */
  34
  35   /* Return new basic block.  */
  36   basic_block (*create_basic_block) (void *head, void *end, basic_block after);
  37
  38   /* Redirect edge E to the given basic block B and update underlying program
  39      representation.  Returns edge representing redirected branch (that may not
  40      be equivalent to E in the case of duplicate edges being removed) or NULL
  41      if edge is not easily redirectable for whatever reason.  */
  42   edge (*redirect_edge_and_branch) (edge e, basic_block b);
  43
  44   /* Same as the above but allows redirecting of fallthru edges.  In that case
  45      newly created forwarder basic block is returned.  The edge must
  46      not be abnormal.  */
  47   basic_block (*redirect_edge_and_branch_force) (edge, basic_block);
  48
  49   /* Remove statements corresponding to a given basic block.  */
  50   void (*delete_basic_block) (basic_block);
  51
  52   /* Creates a new basic block just after basic block B by splitting
  53      everything after specified instruction I.  */
  54   basic_block (*split_block) (basic_block b, void * i);
  55
  56   /* Move block B immediately after block A.  */
  57   bool (*move_block_after) (basic_block b, basic_block a);
  58
  59   /* Return true when blocks A and B can be merged into single basic block.  */
  60   bool (*can_merge_blocks_p) (basic_block a, basic_block b);
  61
  62   /* Merge blocks A and B.  */
  63   void (*merge_blocks) (basic_block a, basic_block b);
  64
  65   /* Predict edge E using PREDICTOR to given PROBABILITY.  */
  66   void (*predict_edge) (edge e, enum br_predictor predictor, int probability);
  67
  68   /* Return true if the one of outgoing edges is already predicted by
  69      PREDICTOR.  */
  70   bool (*predicted_by_p) (basic_block bb, enum br_predictor predictor);
  71
  72   /* Return true when block A can be duplicated.  */
  73   bool (*can_duplicate_block_p) (basic_block a);
  74
  75   /* Duplicate block A.  */
  76   basic_block (*duplicate_block) (basic_block a);
  77
  78   /* Higher level functions representable by primitive operations above if
  79      we didn't have some oddities in RTL and Tree representations.  */
  80   basic_block (*split_edge) (edge);
  81   void (*make_forwarder_block) (edge);
  82
  83   /* Tries to make the edge fallthru.  */
  84   void (*tidy_fallthru_edge) (edge);
  85
  86   /* Say whether a block ends with a call, possibly followed by some
  87      other code that must stay with the call.  */
  88   bool (*block_ends_with_call_p) (basic_block);
  89
  90   /* Say whether a block ends with a conditional branch.  Switches
  91      and unconditional branches do not qualify.  */
  92   bool (*block_ends_with_condjump_p) (basic_block);
  93
  94   /* Add fake edges to the function exit for any non constant and non noreturn
  95      calls, volatile inline assembly in the bitmap of blocks specified by
  96      BLOCKS or to the whole CFG if BLOCKS is zero.  Return the number of blocks
  97      that were split.
  98
  99      The goal is to expose cases in which entering a basic block does not imply
 100      that all subsequent instructions must be executed.  */
 101   int (*flow_call_edges_add) (sbitmap);
 102
 103   /* This function is called immediately after edge E is added to the
 104      edge vector E->dest->preds.  */
 105   void (*execute_on_growing_pred) (edge);
 106
 107   /* This function is called immediately before edge E is removed from
 108      the edge vector E->dest->preds.  */
 109   void (*execute_on_shrinking_pred) (edge);
 110
 111   /* A hook for duplicating loop in CFG, currently this is used
 112      in loop versioning.  */
 113   bool (*cfg_hook_duplicate_loop_to_header_edge) (struct loop *loop, edge e,
 114                                                   struct loops *loops,
 115                                                   unsigned int ndupl,
 116                                                   sbitmap wont_exit,
 117                                                   edge orig, edge *to_remove,
 118                                                   unsigned int *n_to_remove,
 119                                                   int flags);
 120
 121   /* Add condition to new basic block and update CFG used in loop
 122      versioning.  */
 123   void (*lv_add_condition_to_bb) (basic_block, basic_block, basic_block,
 124                                   void *);
 125   /* Update the PHI nodes in case of loop versioning.  */
 126   void (*lv_adjust_loop_header_phi) (basic_block, basic_block,
 127                                      basic_block, edge);
 128
 129   /* Given a condition BB extract the true/false taken/not taken edges
 130      (depending if we are on tree's or RTL). */
 131   void (*extract_cond_bb_edges) (basic_block, edge *, edge *);
 132
 133
 134   /* Add PHI arguments queued in PENDINT_STMT list on edge E to edge
 135      E->dest (only in tree-ssa loop versioning.  */
 136   void (*flush_pending_stmts) (edge);
 137 };
 138
 139 extern void verify_flow_info (void);
 140 extern void dump_bb (basic_block, FILE *, int);
 141 extern edge redirect_edge_and_branch (edge, basic_block);
 142 extern basic_block redirect_edge_and_branch_force (edge, basic_block);
 143 extern edge split_block (basic_block, void *);
 144 extern edge split_block_after_labels (basic_block);
 145 extern bool move_block_after (basic_block, basic_block);
 146 extern void delete_basic_block (basic_block);
 147 extern basic_block split_edge (edge);
 148 extern basic_block create_basic_block (void *, void *, basic_block);
 149 extern basic_block create_empty_bb (basic_block);
 150 extern bool can_merge_blocks_p (basic_block, basic_block);
 151 extern void merge_blocks (basic_block, basic_block);
 152 extern edge make_forwarder_block (basic_block, bool (*)(edge),
 153                                   void (*) (basic_block));
 154 extern void tidy_fallthru_edge (edge);
 155 extern void tidy_fallthru_edges (void);
 156 extern void predict_edge (edge e, enum br_predictor predictor, int probability);
 157 extern bool predicted_by_p (basic_block bb, enum br_predictor predictor);
 158 extern bool can_duplicate_block_p (basic_block);
 159 extern basic_block duplicate_block (basic_block, edge, basic_block);
 160 extern bool block_ends_with_call_p (basic_block bb);
 161 extern bool block_ends_with_condjump_p (basic_block bb);
 162 extern int flow_call_edges_add (sbitmap);
 163 extern void execute_on_growing_pred (edge);
 164 extern void execute_on_shrinking_pred (edge);
 165 extern bool cfg_hook_duplicate_loop_to_header_edge (struct loop *loop, edge,
 166                                                     struct loops *loops,
 167                                                     unsigned int ndupl,
 168                                                     sbitmap wont_exit,
 169                                                     edge orig, edge *to_remove,
 170                                                     unsigned int *n_to_remove,
 171                                                     int flags);
 172
 173 extern void lv_flush_pending_stmts (edge);
 174 extern void extract_cond_bb_edges (basic_block, edge *, edge*);
 175 extern void lv_adjust_loop_header_phi (basic_block, basic_block, basic_block,
 176                                        edge);
 177 extern void lv_add_condition_to_bb (basic_block, basic_block, basic_block,
 178                                     void *);
 179
 180 /* Hooks containers.  */
 181 extern struct cfg_hooks tree_cfg_hooks;
 182 extern struct cfg_hooks rtl_cfg_hooks;
 183 extern struct cfg_hooks cfg_layout_rtl_cfg_hooks;
 184
 185 /* Declarations.  */
 186 extern int ir_type (void);
 187 extern void rtl_register_cfg_hooks (void);
 188 extern void cfg_layout_rtl_register_cfg_hooks (void);
 189 extern void tree_register_cfg_hooks (void);
 190
 191 #endif  /* GCC_CFGHOOKS_H */