gcc/cfghooks.h

   1 /* Hooks for cfg representation specific functions.
   2    Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008
   3    Free Software Foundation, Inc.
   4    Contributed by Sebastian Pop <s.pop@laposte.net>
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify
   9 it under the terms of the GNU General Public License as published by
  10 the Free Software Foundation; either version 3, or (at your option)
  11 any later version.
  12
  13 GCC is distributed in the hope that it will be useful,
  14 but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 GNU General Public License for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING3.  If not see
  20 <http://www.gnu.org/licenses/>.  */
  21
  22 /* Only basic-block.h includes this.  */
  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) (FILE *, basic_block, int, 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   /* Returns true if it is possible to remove the edge by redirecting it
  50      to the destination of the other edge going from its source.  */
  51   bool (*can_remove_branch_p) (const_edge);
  52
  53   /* Remove statements corresponding to a given basic block.  */
  54   void (*delete_basic_block) (basic_block);
  55
  56   /* Creates a new basic block just after basic block B by splitting
  57      everything after specified instruction I.  */
  58   basic_block (*split_block) (basic_block b, void * i);
  59
  60   /* Move block B immediately after block A.  */
  61   bool (*move_block_after) (basic_block b, basic_block a);
  62
  63   /* Return true when blocks A and B can be merged into single basic block.  */
  64   bool (*can_merge_blocks_p) (basic_block a, basic_block b);
  65
  66   /* Merge blocks A and B.  */
  67   void (*merge_blocks) (basic_block a, basic_block b);
  68
  69   /* Predict edge E using PREDICTOR to given PROBABILITY.  */
  70   void (*predict_edge) (edge e, enum br_predictor predictor, int probability);
  71
  72   /* Return true if the one of outgoing edges is already predicted by
  73      PREDICTOR.  */
  74   bool (*predicted_by_p) (const_basic_block bb, enum br_predictor predictor);
  75
  76   /* Return true when block A can be duplicated.  */
  77   bool (*can_duplicate_block_p) (const_basic_block a);
  78
  79   /* Duplicate block A.  */
  80   basic_block (*duplicate_block) (basic_block a);
  81
  82   /* Higher level functions representable by primitive operations above if
  83      we didn't have some oddities in RTL and Tree representations.  */
  84   basic_block (*split_edge) (edge);
  85   void (*make_forwarder_block) (edge);
  86
  87   /* Try to make the edge fallthru.  */
  88   void (*tidy_fallthru_edge) (edge);
  89
  90   /* Make the edge non-fallthru.  */
  91   basic_block (*force_nonfallthru) (edge);
  92
  93   /* Say whether a block ends with a call, possibly followed by some
  94      other code that must stay with the call.  */
  95   bool (*block_ends_with_call_p) (basic_block);
  96
  97   /* Say whether a block ends with a conditional branch.  Switches
  98      and unconditional branches do not qualify.  */
  99   bool (*block_ends_with_condjump_p) (const_basic_block);
 100
 101   /* Add fake edges to the function exit for any non constant and non noreturn
 102      calls, volatile inline assembly in the bitmap of blocks specified by
 103      BLOCKS or to the whole CFG if BLOCKS is zero.  Return the number of blocks
 104      that were split.
 105
 106      The goal is to expose cases in which entering a basic block does not imply
 107      that all subsequent instructions must be executed.  */
 108   int (*flow_call_edges_add) (sbitmap);
 109
 110   /* This function is called immediately after edge E is added to the
 111      edge vector E->dest->preds.  */
 112   void (*execute_on_growing_pred) (edge);
 113
 114   /* This function is called immediately before edge E is removed from
 115      the edge vector E->dest->preds.  */
 116   void (*execute_on_shrinking_pred) (edge);
 117
 118   /* A hook for duplicating loop in CFG, currently this is used
 119      in loop versioning.  */
 120   bool (*cfg_hook_duplicate_loop_to_header_edge) (struct loop *, edge,
 121                                                   unsigned, sbitmap,
 122                                                   edge, VEC (edge, heap) **,
 123                                                   int);
 124
 125   /* Add condition to new basic block and update CFG used in loop
 126      versioning.  */
 127   void (*lv_add_condition_to_bb) (basic_block, basic_block, basic_block,
 128                                   void *);
 129   /* Update the PHI nodes in case of loop versioning.  */
 130   void (*lv_adjust_loop_header_phi) (basic_block, basic_block,
 131                                      basic_block, edge);
 132
 133   /* Given a condition BB extract the true/false taken/not taken edges
 134      (depending if we are on tree's or RTL). */
 135   void (*extract_cond_bb_edges) (basic_block, edge *, edge *);
 136
 137
 138   /* Add PHI arguments queued in PENDINT_STMT list on edge E to edge
 139      E->dest (only in tree-ssa loop versioning.  */
 140   void (*flush_pending_stmts) (edge);
 141
 142   /* True if a block contains no executable instructions.  */
 143   bool (*empty_block_p) (basic_block);
 144
 145   /* Split a basic block if it ends with a conditional branch and if
 146      the other part of the block is not empty.  */
 147   basic_block (*split_block_before_cond_jump) (basic_block);
 148 };
 149
 150 extern void verify_flow_info (void);
 151 extern void dump_bb (FILE *, basic_block, int, int);
 152 extern edge redirect_edge_and_branch (edge, basic_block);
 153 extern basic_block redirect_edge_and_branch_force (edge, basic_block);
 154 extern bool can_remove_branch_p (const_edge);
 155 extern void remove_branch (edge);
 156 extern void remove_edge (edge);
 157 extern edge split_block (basic_block, void *);
 158 extern edge split_block_after_labels (basic_block);
 159 extern bool move_block_after (basic_block, basic_block);
 160 extern void delete_basic_block (basic_block);
 161 extern basic_block split_edge (edge);
 162 extern basic_block create_basic_block (void *, void *, basic_block);
 163 extern basic_block create_empty_bb (basic_block);
 164 extern bool can_merge_blocks_p (basic_block, basic_block);
 165 extern void merge_blocks (basic_block, basic_block);
 166 extern edge make_forwarder_block (basic_block, bool (*)(edge),
 167                                   void (*) (basic_block));
 168 extern basic_block force_nonfallthru (edge);
 169 extern void tidy_fallthru_edge (edge);
 170 extern void tidy_fallthru_edges (void);
 171 extern void predict_edge (edge e, enum br_predictor predictor, int probability);
 172 extern bool predicted_by_p (const_basic_block bb, enum br_predictor predictor);
 173 extern bool can_duplicate_block_p (const_basic_block);
 174 extern basic_block duplicate_block (basic_block, edge, basic_block);
 175 extern bool block_ends_with_call_p (basic_block bb);
 176 extern bool empty_block_p (basic_block);
 177 extern basic_block split_block_before_cond_jump (basic_block);
 178 extern bool block_ends_with_condjump_p (const_basic_block bb);
 179 extern int flow_call_edges_add (sbitmap);
 180 extern void execute_on_growing_pred (edge);
 181 extern void execute_on_shrinking_pred (edge);
 182 extern bool cfg_hook_duplicate_loop_to_header_edge (struct loop *loop, edge,
 183                                                     unsigned int ndupl,
 184                                                     sbitmap wont_exit,
 185                                                     edge orig,
 186                                                     VEC (edge, heap) **to_remove,
 187                                                     int flags);
 188
 189 extern void lv_flush_pending_stmts (edge);
 190 extern void extract_cond_bb_edges (basic_block, edge *, edge*);
 191 extern void lv_adjust_loop_header_phi (basic_block, basic_block, basic_block,
 192                                        edge);
 193 extern void lv_add_condition_to_bb (basic_block, basic_block, basic_block,
 194                                     void *);
 195
 196 extern bool can_copy_bbs_p (basic_block *, unsigned);
 197 extern void copy_bbs (basic_block *, unsigned, basic_block *,
 198                       edge *, unsigned, edge *, struct loop *,
 199                       basic_block);
 200
 201 extern void cfg_layout_initialize (unsigned int);
 202 extern void cfg_layout_finalize (void);
 203
 204 /* Hooks containers.  */
 205 extern struct cfg_hooks gimple_cfg_hooks;
 206 extern struct cfg_hooks rtl_cfg_hooks;
 207 extern struct cfg_hooks cfg_layout_rtl_cfg_hooks;
 208
 209 /* Declarations.  */
 210 extern enum ir_type current_ir_type (void);
 211 extern void rtl_register_cfg_hooks (void);
 212 extern void cfg_layout_rtl_register_cfg_hooks (void);
 213 extern void gimple_register_cfg_hooks (void);
 214 extern struct cfg_hooks get_cfg_hooks (void);
 215 extern void set_cfg_hooks (struct cfg_hooks);
 216