gcc/cfghooks.h

   1 /* Hooks for cfg representation specific functions.
   2    Copyright (C) 2003, 2004, 2005 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 2, 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 COPYING.  If not, write to
  19 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
  20 Boston, MA 02110-1301, USA.  */
  21
  22 #ifndef GCC_CFGHOOKS_H
  23 #define GCC_CFGHOOKS_H
  24
  25 struct cfg_hooks
  26 {
  27   /* Name of the corresponding ir.  */
  28   const char *name;
  29
  30   /* Debugging.  */
  31   int (*verify_flow_info) (void);
  32   void (*dump_bb) (basic_block, FILE *, int);
  33
  34   /* Basic CFG manipulation.  */
  35
  36   /* Return new basic block.  */
  37   basic_block (*create_basic_block) (void *head, void *end, basic_block after);
  38
  39   /* Redirect edge E to the given basic block B and update underlying program
  40      representation.  Returns edge representing redirected branch (that may not
  41      be equivalent to E in the case of duplicate edges being removed) or NULL
  42      if edge is not easily redirectable for whatever reason.  */
  43   edge (*redirect_edge_and_branch) (edge e, basic_block b);
  44
  45   /* Same as the above but allows redirecting of fallthru edges.  In that case
  46      newly created forwarder basic block is returned.  The edge must
  47      not be abnormal.  */
  48   basic_block (*redirect_edge_and_branch_force) (edge, basic_block);
  49
  50   /* Returns true if it is possible to remove the edge by redirecting it
  51      to the destination of the other edge going from its source.  */
  52   bool (*can_remove_branch_p) (edge);
  53
  54   /* Remove statements corresponding to a given basic block.  */
  55   void (*delete_basic_block) (basic_block);
  56
  57   /* Creates a new basic block just after basic block B by splitting
  58      everything after specified instruction I.  */
  59   basic_block (*split_block) (basic_block b, void * i);
  60
  61   /* Move block B immediately after block A.  */
  62   bool (*move_block_after) (basic_block b, basic_block a);
  63
  64   /* Return true when blocks A and B can be merged into single basic block.  */
  65   bool (*can_merge_blocks_p) (basic_block a, basic_block b);
  66
  67   /* Merge blocks A and B.  */
  68   void (*merge_blocks) (basic_block a, basic_block b);
  69
  70   /* Predict edge E using PREDICTOR to given PROBABILITY.  */
  71   void (*predict_edge) (edge e, enum br_predictor predictor, int probability);
  72
  73   /* Return true if the one of outgoing edges is already predicted by
  74      PREDICTOR.  */
  75   bool (*predicted_by_p) (basic_block bb, enum br_predictor predictor);
  76
  77   /* Return true when block A can be duplicated.  */
  78   bool (*can_duplicate_block_p) (basic_block a);
  79
  80   /* Duplicate block A.  */
  81   basic_block (*duplicate_block) (basic_block a);
  82
  83   /* Higher level functions representable by primitive operations above if
  84      we didn't have some oddities in RTL and Tree representations.  */
  85   basic_block (*split_edge) (edge);
  86   void (*make_forwarder_block) (edge);
  87
  88   /* Tries to make the edge fallthru.  */
  89   void (*tidy_fallthru_edge) (edge);
  90
  91   /* Say whether a block ends with a call, possibly followed by some
  92      other code that must stay with the call.  */
  93   bool (*block_ends_with_call_p) (basic_block);
  94
  95   /* Say whether a block ends with a conditional branch.  Switches
  96      and unconditional branches do not qualify.  */
  97   bool (*block_ends_with_condjump_p) (basic_block);
  98
  99   /* Add fake edges to the function exit for any non constant and non noreturn
 100      calls, volatile inline assembly in the bitmap of blocks specified by
 101      BLOCKS or to the whole CFG if BLOCKS is zero.  Return the number of blocks
 102      that were split.
 103
 104      The goal is to expose cases in which entering a basic block does not imply
 105      that all subsequent instructions must be executed.  */
 106   int (*flow_call_edges_add) (sbitmap);
 107
 108   /* This function is called immediately after edge E is added to the
 109      edge vector E->dest->preds.  */
 110   void (*execute_on_growing_pred) (edge);
 111
 112   /* This function is called immediately before edge E is removed from
 113      the edge vector E->dest->preds.  */
 114   void (*execute_on_shrinking_pred) (edge);
 115
 116   /* A hook for duplicating loop in CFG, currently this is used
 117      in loop versioning.  */
 118   bool (*cfg_hook_duplicate_loop_to_header_edge) (struct loop *, edge,
 119                                                   unsigned, sbitmap,
 120                                                   edge, VEC (edge, heap) **,
 121                                                   int);
 122
 123   /* Add condition to new basic block and update CFG used in loop
 124      versioning.  */
 125   void (*lv_add_condition_to_bb) (basic_block, basic_block, basic_block,
 126                                   void *);
 127   /* Update the PHI nodes in case of loop versioning.  */
 128   void (*lv_adjust_loop_header_phi) (basic_block, basic_block,
 129                                      basic_block, edge);
 130
 131   /* Given a condition BB extract the true/false taken/not taken edges
 132      (depending if we are on tree's or RTL). */
 133   void (*extract_cond_bb_edges) (basic_block, edge *, edge *);
 134
 135
 136   /* Add PHI arguments queued in PENDINT_STMT list on edge E to edge
 137      E->dest (only in tree-ssa loop versioning.  */
 138   void (*flush_pending_stmts) (edge);
 139 };
 140
 141 extern void verify_flow_info (void);
 142 extern void dump_bb (basic_block, FILE *, int);
 143 extern edge redirect_edge_and_branch (edge, basic_block);
 144 extern basic_block redirect_edge_and_branch_force (edge, basic_block);
 145 extern bool can_remove_branch_p (edge);
 146 extern void remove_branch (edge);
 147 extern edge split_block (basic_block, void *);
 148 extern edge split_block_after_labels (basic_block);
 149 extern bool move_block_after (basic_block, basic_block);
 150 extern void delete_basic_block (basic_block);
 151 extern basic_block split_edge (edge);
 152 extern basic_block create_basic_block (void *, void *, basic_block);
 153 extern basic_block create_empty_bb (basic_block);
 154 extern bool can_merge_blocks_p (basic_block, basic_block);
 155 extern void merge_blocks (basic_block, basic_block);
 156 extern edge make_forwarder_block (basic_block, bool (*)(edge),
 157                                   void (*) (basic_block));
 158 extern void tidy_fallthru_edge (edge);
 159 extern void tidy_fallthru_edges (void);
 160 extern void predict_edge (edge e, enum br_predictor predictor, int probability);
 161 extern bool predicted_by_p (basic_block bb, enum br_predictor predictor);
 162 extern bool can_duplicate_block_p (basic_block);
 163 extern basic_block duplicate_block (basic_block, edge, basic_block);
 164 extern bool block_ends_with_call_p (basic_block bb);
 165 extern bool block_ends_with_condjump_p (basic_block bb);
 166 extern int flow_call_edges_add (sbitmap);
 167 extern void execute_on_growing_pred (edge);
 168 extern void execute_on_shrinking_pred (edge);
 169 extern bool cfg_hook_duplicate_loop_to_header_edge (struct loop *loop, edge,
 170                                                     unsigned int ndupl,
 171                                                     sbitmap wont_exit,
 172                                                     edge orig,
 173                                                     VEC (edge, heap) **to_remove,
 174                                                     int flags);
 175
 176 extern void lv_flush_pending_stmts (edge);
 177 extern void extract_cond_bb_edges (basic_block, edge *, edge*);
 178 extern void lv_adjust_loop_header_phi (basic_block, basic_block, basic_block,
 179                                        edge);
 180 extern void lv_add_condition_to_bb (basic_block, basic_block, basic_block,
 181                                     void *);
 182
 183 /* Hooks containers.  */
 184 extern struct cfg_hooks tree_cfg_hooks;
 185 extern struct cfg_hooks rtl_cfg_hooks;
 186 extern struct cfg_hooks cfg_layout_rtl_cfg_hooks;
 187
 188 /* Declarations.  */
 189 extern enum ir_type current_ir_type (void);
 190 extern void rtl_register_cfg_hooks (void);
 191 extern void cfg_layout_rtl_register_cfg_hooks (void);
 192 extern void tree_register_cfg_hooks (void);
 193
 194 #endif  /* GCC_CFGHOOKS_H */