gcc/gimple-iterator.h

   1 /* Header file for gimple iterators.
   2    Copyright (C) 2013-2018 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 3, or (at your option) any later
   9 version.
  10
  11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef GCC_GIMPLE_ITERATOR_H
  21 #define GCC_GIMPLE_ITERATOR_H
  22
  23 /* Iterator object for GIMPLE statement sequences.  */
  24
  25 struct gimple_stmt_iterator
  26 {
  27   /* Sequence node holding the current statement.  */
  28   gimple_seq_node ptr;
  29
  30   /* Sequence and basic block holding the statement.  These fields
  31      are necessary to handle edge cases such as when statement is
  32      added to an empty basic block or when the last statement of a
  33      block/sequence is removed.  */
  34   gimple_seq *seq;
  35   basic_block bb;
  36 };
  37
  38 /* Iterator over GIMPLE_PHI statements.  */
  39 struct gphi_iterator : public gimple_stmt_iterator
  40 {
  41   gphi *phi () const
  42   {
  43     return as_a <gphi *> (ptr);
  44   }
  45 };
  46
  47 enum gsi_iterator_update
  48 {
  49   GSI_NEW_STMT,         /* Only valid when single statement is added, move
  50                            iterator to it.  */
  51   GSI_SAME_STMT,        /* Leave the iterator at the same statement.  */
  52   GSI_CONTINUE_LINKING  /* Move iterator to whatever position is suitable
  53                            for linking other statements in the same
  54                            direction.  */
  55 };
  56
  57 extern void gsi_insert_seq_before_without_update (gimple_stmt_iterator *,
  58                                                   gimple_seq,
  59                                                   enum gsi_iterator_update);
  60 extern void gsi_insert_seq_before (gimple_stmt_iterator *, gimple_seq,
  61                                    enum gsi_iterator_update);
  62 extern void gsi_insert_seq_after_without_update (gimple_stmt_iterator *,
  63                                                  gimple_seq,
  64                                                  enum gsi_iterator_update);
  65 extern void gsi_insert_seq_after (gimple_stmt_iterator *, gimple_seq,
  66                                   enum gsi_iterator_update);
  67 extern gimple_seq gsi_split_seq_after (gimple_stmt_iterator);
  68 extern void gsi_set_stmt (gimple_stmt_iterator *, gimple *);
  69 extern void gsi_split_seq_before (gimple_stmt_iterator *, gimple_seq *);
  70 extern bool gsi_replace (gimple_stmt_iterator *, gimple *, bool);
  71 extern void gsi_replace_with_seq (gimple_stmt_iterator *, gimple_seq, bool);
  72 extern void gsi_insert_before_without_update (gimple_stmt_iterator *, gimple *,
  73                                               enum gsi_iterator_update);
  74 extern void gsi_insert_before (gimple_stmt_iterator *, gimple *,
  75                                enum gsi_iterator_update);
  76 extern void gsi_insert_after_without_update (gimple_stmt_iterator *, gimple *,
  77                                              enum gsi_iterator_update);
  78 extern void gsi_insert_after (gimple_stmt_iterator *, gimple *,
  79                               enum gsi_iterator_update);
  80 extern bool gsi_remove (gimple_stmt_iterator *, bool);
  81 extern gimple_stmt_iterator gsi_for_stmt (gimple *);
  82 extern gphi_iterator gsi_for_phi (gphi *);
  83 extern void gsi_move_after (gimple_stmt_iterator *, gimple_stmt_iterator *);
  84 extern void gsi_move_before (gimple_stmt_iterator *, gimple_stmt_iterator *);
  85 extern void gsi_move_to_bb_end (gimple_stmt_iterator *, basic_block);
  86 extern void gsi_insert_on_edge (edge, gimple *);
  87 extern void gsi_insert_seq_on_edge (edge, gimple_seq);
  88 extern basic_block gsi_insert_on_edge_immediate (edge, gimple *);
  89 extern basic_block gsi_insert_seq_on_edge_immediate (edge, gimple_seq);
  90 extern void gsi_commit_edge_inserts (void);
  91 extern void gsi_commit_one_edge_insert (edge, basic_block *);
  92 extern gphi_iterator gsi_start_phis (basic_block);
  93 extern void update_modified_stmts (gimple_seq);
  94
  95 /* Return a new iterator pointing to GIMPLE_SEQ's first statement.  */
  96
  97 static inline gimple_stmt_iterator
  98 gsi_start_1 (gimple_seq *seq)
  99 {
 100   gimple_stmt_iterator i;
 101
 102   i.ptr = gimple_seq_first (*seq);
 103   i.seq = seq;
 104   i.bb = i.ptr ? gimple_bb (i.ptr) : NULL;
 105
 106   return i;
 107 }
 108
 109 #define gsi_start(x) gsi_start_1 (&(x))
 110
 111 static inline gimple_stmt_iterator
 112 gsi_none (void)
 113 {
 114   gimple_stmt_iterator i;
 115   i.ptr = NULL;
 116   i.seq = NULL;
 117   i.bb = NULL;
 118   return i;
 119 }
 120
 121 /* Return a new iterator pointing to the first statement in basic block BB.  */
 122
 123 static inline gimple_stmt_iterator
 124 gsi_start_bb (basic_block bb)
 125 {
 126   gimple_stmt_iterator i;
 127   gimple_seq *seq;
 128
 129   seq = bb_seq_addr (bb);
 130   i.ptr = gimple_seq_first (*seq);
 131   i.seq = seq;
 132   i.bb = bb;
 133
 134   return i;
 135 }
 136
 137 gimple_stmt_iterator gsi_start_edge (edge e);
 138
 139 /* Return a new iterator initially pointing to GIMPLE_SEQ's last statement.  */
 140
 141 static inline gimple_stmt_iterator
 142 gsi_last_1 (gimple_seq *seq)
 143 {
 144   gimple_stmt_iterator i;
 145
 146   i.ptr = gimple_seq_last (*seq);
 147   i.seq = seq;
 148   i.bb = i.ptr ? gimple_bb (i.ptr) : NULL;
 149
 150   return i;
 151 }
 152
 153 #define gsi_last(x) gsi_last_1 (&(x))
 154
 155 /* Return a new iterator pointing to the last statement in basic block BB.  */
 156
 157 static inline gimple_stmt_iterator
 158 gsi_last_bb (basic_block bb)
 159 {
 160   gimple_stmt_iterator i;
 161   gimple_seq *seq;
 162
 163   seq = bb_seq_addr (bb);
 164   i.ptr = gimple_seq_last (*seq);
 165   i.seq = seq;
 166   i.bb = bb;
 167
 168   return i;
 169 }
 170
 171 /* Return true if I is at the end of its sequence.  */
 172
 173 static inline bool
 174 gsi_end_p (gimple_stmt_iterator i)
 175 {
 176   return i.ptr == NULL;
 177 }
 178
 179 /* Return true if I is one statement before the end of its sequence.  */
 180
 181 static inline bool
 182 gsi_one_before_end_p (gimple_stmt_iterator i)
 183 {
 184   return i.ptr != NULL && i.ptr->next == NULL;
 185 }
 186
 187 /* Advance the iterator to the next gimple statement.  */
 188
 189 static inline void
 190 gsi_next (gimple_stmt_iterator *i)
 191 {
 192   i->ptr = i->ptr->next;
 193 }
 194
 195 /* Advance the iterator to the previous gimple statement.  */
 196
 197 static inline void
 198 gsi_prev (gimple_stmt_iterator *i)
 199 {
 200   gimple *prev = i->ptr->prev;
 201   if (prev->next)
 202     i->ptr = prev;
 203   else
 204     i->ptr = NULL;
 205 }
 206
 207 /* Return the current stmt.  */
 208
 209 static inline gimple *
 210 gsi_stmt (gimple_stmt_iterator i)
 211 {
 212   return i.ptr;
 213 }
 214
 215 /* Return a block statement iterator that points to the first
 216    non-label statement in block BB.  */
 217
 218 static inline gimple_stmt_iterator
 219 gsi_after_labels (basic_block bb)
 220 {
 221   gimple_stmt_iterator gsi = gsi_start_bb (bb);
 222
 223   for (; !gsi_end_p (gsi); )
 224     {
 225       if (gimple_code (gsi_stmt (gsi)) == GIMPLE_LABEL)
 226         gsi_next (&gsi);
 227       else
 228         break;
 229     }
 230
 231   return gsi;
 232 }
 233
 234 /* Advance the iterator to the next non-debug gimple statement.  */
 235
 236 static inline void
 237 gsi_next_nondebug (gimple_stmt_iterator *i)
 238 {
 239   do
 240     {
 241       gsi_next (i);
 242     }
 243   while (!gsi_end_p (*i) && is_gimple_debug (gsi_stmt (*i)));
 244 }
 245
 246 /* Advance the iterator to the previous non-debug gimple statement.  */
 247
 248 static inline void
 249 gsi_prev_nondebug (gimple_stmt_iterator *i)
 250 {
 251   do
 252     {
 253       gsi_prev (i);
 254     }
 255   while (!gsi_end_p (*i) && is_gimple_debug (gsi_stmt (*i)));
 256 }
 257
 258 /* Return a new iterator pointing to the first non-debug statement in
 259    SEQ.  */
 260
 261 static inline gimple_stmt_iterator
 262 gsi_start_nondebug (gimple_seq seq)
 263 {
 264   gimple_stmt_iterator gsi = gsi_start (seq);
 265   if (!gsi_end_p (gsi) && is_gimple_debug (gsi_stmt (gsi)))
 266     gsi_next_nondebug (&gsi);
 267
 268   return gsi;
 269 }
 270
 271 /* Return a new iterator pointing to the first non-debug statement in
 272    basic block BB.  */
 273
 274 static inline gimple_stmt_iterator
 275 gsi_start_nondebug_bb (basic_block bb)
 276 {
 277   gimple_stmt_iterator i = gsi_start_bb (bb);
 278
 279   if (!gsi_end_p (i) && is_gimple_debug (gsi_stmt (i)))
 280     gsi_next_nondebug (&i);
 281
 282   return i;
 283 }
 284
 285 /* Return a new iterator pointing to the first non-debug non-label statement in
 286    basic block BB.  */
 287
 288 static inline gimple_stmt_iterator
 289 gsi_start_nondebug_after_labels_bb (basic_block bb)
 290 {
 291   gimple_stmt_iterator i = gsi_after_labels (bb);
 292
 293   if (!gsi_end_p (i) && is_gimple_debug (gsi_stmt (i)))
 294     gsi_next_nondebug (&i);
 295
 296   return i;
 297 }
 298
 299 /* Return a new iterator pointing to the last non-debug statement in
 300    basic block BB.  */
 301
 302 static inline gimple_stmt_iterator
 303 gsi_last_nondebug_bb (basic_block bb)
 304 {
 305   gimple_stmt_iterator i = gsi_last_bb (bb);
 306
 307   if (!gsi_end_p (i) && is_gimple_debug (gsi_stmt (i)))
 308     gsi_prev_nondebug (&i);
 309
 310   return i;
 311 }
 312
 313 /* Return true if I is followed only by debug statements in its
 314    sequence.  */
 315
 316 static inline bool
 317 gsi_one_nondebug_before_end_p (gimple_stmt_iterator i)
 318 {
 319   if (gsi_one_before_end_p (i))
 320     return true;
 321   if (gsi_end_p (i))
 322     return false;
 323   gsi_next_nondebug (&i);
 324   return gsi_end_p (i);
 325 }
 326
 327 /* Iterates I statement iterator to the next non-virtual statement.  */
 328
 329 static inline void
 330 gsi_next_nonvirtual_phi (gphi_iterator *i)
 331 {
 332   gphi *phi;
 333
 334   if (gsi_end_p (*i))
 335     return;
 336
 337   phi = i->phi ();
 338   gcc_assert (phi != NULL);
 339
 340   while (virtual_operand_p (gimple_phi_result (phi)))
 341     {
 342       gsi_next (i);
 343
 344       if (gsi_end_p (*i))
 345         return;
 346
 347       phi = i->phi ();
 348     }
 349 }
 350
 351 /* Return the basic block associated with this iterator.  */
 352
 353 static inline basic_block
 354 gsi_bb (gimple_stmt_iterator i)
 355 {
 356   return i.bb;
 357 }
 358
 359 /* Return the sequence associated with this iterator.  */
 360
 361 static inline gimple_seq
 362 gsi_seq (gimple_stmt_iterator i)
 363 {
 364   return *i.seq;
 365 }
 366
 367 /* Determine whether SEQ is a nondebug singleton.  */
 368
 369 static inline bool
 370 gimple_seq_nondebug_singleton_p (gimple_seq seq)
 371 {
 372   gimple_stmt_iterator gsi;
 373
 374   /* Find a nondebug gimple.  */
 375   gsi.ptr = gimple_seq_first (seq);
 376   gsi.seq = &seq;
 377   gsi.bb = NULL;
 378   while (!gsi_end_p (gsi)
 379          && is_gimple_debug (gsi_stmt (gsi)))
 380     gsi_next (&gsi);
 381
 382   /* No nondebug gimple found, not a singleton.  */
 383   if (gsi_end_p (gsi))
 384     return false;
 385
 386   /* Find a next nondebug gimple.  */
 387   gsi_next (&gsi);
 388   while (!gsi_end_p (gsi)
 389          && is_gimple_debug (gsi_stmt (gsi)))
 390     gsi_next (&gsi);
 391
 392   /* Only a singleton if there's no next nondebug gimple.  */
 393   return gsi_end_p (gsi);
 394 }
 395
 396 #endif /* GCC_GIMPLE_ITERATOR_H */