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 #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, 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) (const_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) (const_basic_block bb, enum br_predictor predictor);
  76
  77   /* Return true when block A can be duplicated.  */
  78   bool (*can_duplicate_block_p) (const_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   /* Try to make the edge fallthru.  */
  89   void (*tidy_fallthru_edge) (edge);
  90
  91   /* Make the edge non-fallthru.  */
  92   basic_block (*force_nonfallthru) (edge);
  93
  94   /* Say whether a block ends with a call, possibly followed by some
  95      other code that must stay with the call.  */
  96   bool (*block_ends_with_call_p) (basic_block);
  97
  98   /* Say whether a block ends with a conditional branch.  Switches
  99      and unconditional branches do not qualify.  */
 100   bool (*block_ends_with_condjump_p) (const_basic_block);
 101
 102   /* Add fake edges to the function exit for any non constant and non noreturn
 103      calls, volatile inline assembly in the bitmap of blocks specified by
 104      BLOCKS or to the whole CFG if BLOCKS is zero.  Return the number of blocks
 105      that were split.
 106
 107      The goal is to expose cases in which entering a basic block does not imply
 108      that all subsequent instructions must be executed.  */
 109   int (*flow_call_edges_add) (sbitmap);
 110
 111   /* This function is called immediately after edge E is added to the
 112      edge vector E->dest->preds.  */
 113   void (*execute_on_growing_pred) (edge);
 114
 115   /* This function is called immediately before edge E is removed from
 116      the edge vector E->dest->preds.  */
 117   void (*execute_on_shrinking_pred) (edge);
 118
 119   /* A hook for duplicating loop in CFG, currently this is used
 120      in loop versioning.  */
 121   bool (*cfg_hook_duplicate_loop_to_header_edge) (struct loop *, edge,
 122                                                   unsigned, sbitmap,
 123                                                   edge, VEC (edge, heap) **,
 124                                                   int);
 125
 126   /* Add condition to new basic block and update CFG used in loop
 127      versioning.  */
 128   void (*lv_add_condition_to_bb) (basic_block, basic_block, basic_block,
 129                                   void *);
 130   /* Update the PHI nodes in case of loop versioning.  */
 131   void (*lv_adjust_loop_header_phi) (basic_block, basic_block,
 132                                      basic_block, edge);
 133
 134   /* Given a condition BB extract the true/false taken/not taken edges
 135      (depending if we are on tree's or RTL). */
 136   void (*extract_cond_bb_edges) (basic_block, edge *, edge *);
 137
 138
 139   /* Add PHI arguments queued in PENDINT_STMT list on edge E to edge
 140      E->dest (only in tree-ssa loop versioning.  */
 141   void (*flush_pending_stmts) (edge);
 142 };
 143
 144 extern void verify_flow_info (void);
 145 extern void dump_bb (basic_block, FILE *, int);
 146 extern edge redirect_edge_and_branch (edge, basic_block);
 147 extern basic_block redirect_edge_and_branch_force (edge, basic_block);
 148 extern bool can_remove_branch_p (const_edge);
 149 extern void remove_branch (edge);
 150 extern void remove_edge (edge);
 151 extern edge split_block (basic_block, void *);
 152 extern edge split_block_after_labels (basic_block);
 153 extern bool move_block_after (basic_block, basic_block);
 154 extern void delete_basic_block (basic_block);
 155 extern basic_block split_edge (edge);
 156 extern basic_block create_basic_block (void *, void *, basic_block);
 157 extern basic_block create_empty_bb (basic_block);
 158 extern bool can_merge_blocks_p (basic_block, basic_block);
 159 extern void merge_blocks (basic_block, basic_block);
 160 extern edge make_forwarder_block (basic_block, bool (*)(edge),
 161                                   void (*) (basic_block));
 162 extern basic_block force_nonfallthru (edge);
 163 extern void tidy_fallthru_edge (edge);
 164 extern void tidy_fallthru_edges (void);
 165 extern void predict_edge (edge e, enum br_predictor predictor, int probability);
 166 extern bool predicted_by_p (const_basic_block bb, enum br_predictor predictor);
 167 extern bool can_duplicate_block_p (const_basic_block);
 168 extern basic_block duplicate_block (basic_block, edge, basic_block);
 169 extern bool block_ends_with_call_p (basic_block bb);
 170 extern bool block_ends_with_condjump_p (const_basic_block bb);
 171 extern int flow_call_edges_add (sbitmap);
 172 extern void execute_on_growing_pred (edge);
 173 extern void execute_on_shrinking_pred (edge);
 174 extern bool cfg_hook_duplicate_loop_to_header_edge (struct loop *loop, edge,
 175                                                     unsigned int ndupl,
 176                                                     sbitmap wont_exit,
 177                                                     edge orig,
 178                                                     VEC (edge, heap) **to_remove,
 179                                                     int flags);
 180
 181 extern void lv_flush_pending_stmts (edge);
 182 extern void extract_cond_bb_edges (basic_block, edge *, edge*);
 183 extern void lv_adjust_loop_header_phi (basic_block, basic_block, basic_block,
 184                                        edge);
 185 extern void lv_add_condition_to_bb (basic_block, basic_block, basic_block,
 186                                     void *);
 187
 188 /* Hooks containers.  */
 189 extern struct cfg_hooks gimple_cfg_hooks;
 190 extern struct cfg_hooks rtl_cfg_hooks;
 191 extern struct cfg_hooks cfg_layout_rtl_cfg_hooks;
 192
 193 /* Declarations.  */
 194 extern enum ir_type current_ir_type (void);
 195 extern void rtl_register_cfg_hooks (void);
 196 extern void cfg_layout_rtl_register_cfg_hooks (void);
 197 extern void gimple_register_cfg_hooks (void);
 198 extern struct cfg_hooks get_cfg_hooks (void);
 199 extern void set_cfg_hooks (struct cfg_hooks);
 200
 201 #endif  /* GCC_CFGHOOKS_H */