gcc/gimple-iterator.h

   1 /* Header file for gimple iterators.
   2    Copyright (C) 2013-2021 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 = 2,     /* Move the iterator to the first statement added.  */
  50   GSI_LAST_NEW_STMT,    /* Move the iterator to the last statement added.  */
  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 gimple_stmt_iterator gsi_for_stmt (gimple *, gimple_seq *);
  83 extern gphi_iterator gsi_for_phi (gphi *);
  84 extern void gsi_move_after (gimple_stmt_iterator *, gimple_stmt_iterator *);
  85 extern void gsi_move_before (gimple_stmt_iterator *, gimple_stmt_iterator *);
  86 extern void gsi_move_to_bb_end (gimple_stmt_iterator *, basic_block);
  87 extern void gsi_insert_on_edge (edge, gimple *);
  88 extern void gsi_insert_seq_on_edge (edge, gimple_seq);
  89 extern basic_block gsi_insert_on_edge_immediate (edge, gimple *);
  90 extern basic_block gsi_insert_seq_on_edge_immediate (edge, gimple_seq);
  91 extern void gsi_commit_edge_inserts (void);
  92 extern void gsi_commit_one_edge_insert (edge, basic_block *);
  93 extern gphi_iterator gsi_start_phis (basic_block);
  94 extern void update_modified_stmts (gimple_seq);
  95
  96 /* Return a new iterator pointing to GIMPLE_SEQ's first statement.  */
  97
  98 static inline gimple_stmt_iterator
  99 gsi_start_1 (gimple_seq *seq)
 100 {
 101   gimple_stmt_iterator i;
 102
 103   i.ptr = gimple_seq_first (*seq);
 104   i.seq = seq;
 105   i.bb = i.ptr ? gimple_bb (i.ptr) : NULL;
 106
 107   return i;
 108 }
 109
 110 #define gsi_start(x) gsi_start_1 (&(x))
 111
 112 static inline gimple_stmt_iterator
 113 gsi_none (void)
 114 {
 115   gimple_stmt_iterator i;
 116   i.ptr = NULL;
 117   i.seq = NULL;
 118   i.bb = NULL;
 119   return i;
 120 }
 121
 122 /* Return a new iterator pointing to the first statement in basic block BB.  */
 123
 124 static inline gimple_stmt_iterator
 125 gsi_start_bb (basic_block bb)
 126 {
 127   gimple_stmt_iterator i;
 128   gimple_seq *seq;
 129
 130   seq = bb_seq_addr (bb);
 131   i.ptr = gimple_seq_first (*seq);
 132   i.seq = seq;
 133   i.bb = bb;
 134
 135   return i;
 136 }
 137
 138 gimple_stmt_iterator gsi_start_edge (edge e);
 139
 140 /* Return a new iterator initially pointing to GIMPLE_SEQ's last statement.  */
 141
 142 static inline gimple_stmt_iterator
 143 gsi_last_1 (gimple_seq *seq)
 144 {
 145   gimple_stmt_iterator i;
 146
 147   i.ptr = gimple_seq_last (*seq);
 148   i.seq = seq;
 149   i.bb = i.ptr ? gimple_bb (i.ptr) : NULL;
 150
 151   return i;
 152 }
 153
 154 #define gsi_last(x) gsi_last_1 (&(x))
 155
 156 /* Return a new iterator pointing to the last statement in basic block BB.  */
 157
 158 static inline gimple_stmt_iterator
 159 gsi_last_bb (basic_block bb)
 160 {
 161   gimple_stmt_iterator i;
 162   gimple_seq *seq;
 163
 164   seq = bb_seq_addr (bb);
 165   i.ptr = gimple_seq_last (*seq);
 166   i.seq = seq;
 167   i.bb = bb;
 168
 169   return i;
 170 }
 171
 172 /* Return true if I is at the end of its sequence.  */
 173
 174 static inline bool
 175 gsi_end_p (gimple_stmt_iterator i)
 176 {
 177   return i.ptr == NULL;
 178 }
 179
 180 /* Return true if I is one statement before the end of its sequence.  */
 181
 182 static inline bool
 183 gsi_one_before_end_p (gimple_stmt_iterator i)
 184 {
 185   return i.ptr != NULL && i.ptr->next == NULL;
 186 }
 187
 188 /* Advance the iterator to the next gimple statement.  */
 189
 190 static inline void
 191 gsi_next (gimple_stmt_iterator *i)
 192 {
 193   i->ptr = i->ptr->next;
 194 }
 195
 196 /* Advance the iterator to the previous gimple statement.  */
 197
 198 static inline void
 199 gsi_prev (gimple_stmt_iterator *i)
 200 {
 201   gimple *prev = i->ptr->prev;
 202   if (prev->next)
 203     i->ptr = prev;
 204   else
 205     i->ptr = NULL;
 206 }
 207
 208 /* Return the current stmt.  */
 209
 210 static inline gimple *
 211 gsi_stmt (gimple_stmt_iterator i)
 212 {
 213   return i.ptr;
 214 }
 215
 216 /* Return a block statement iterator that points to the first
 217    non-label statement in block BB.  */
 218
 219 static inline gimple_stmt_iterator
 220 gsi_after_labels (basic_block bb)
 221 {
 222   gimple_stmt_iterator gsi = gsi_start_bb (bb);
 223
 224   for (; !gsi_end_p (gsi); )
 225     {
 226       if (gimple_code (gsi_stmt (gsi)) == GIMPLE_LABEL)
 227         gsi_next (&gsi);
 228       else
 229         break;
 230     }
 231
 232   return gsi;
 233 }
 234
 235 /* Advance the iterator to the next non-debug gimple statement.  */
 236
 237 static inline void
 238 gsi_next_nondebug (gimple_stmt_iterator *i)
 239 {
 240   do
 241     {
 242       gsi_next (i);
 243     }
 244   while (!gsi_end_p (*i) && is_gimple_debug (gsi_stmt (*i)));
 245 }
 246
 247 /* Advance the iterator to the previous non-debug gimple statement.  */
 248
 249 static inline void
 250 gsi_prev_nondebug (gimple_stmt_iterator *i)
 251 {
 252   do
 253     {
 254       gsi_prev (i);
 255     }
 256   while (!gsi_end_p (*i) && is_gimple_debug (gsi_stmt (*i)));
 257 }
 258
 259 /* Return a new iterator pointing to the first non-debug statement in
 260    SEQ.  */
 261
 262 static inline gimple_stmt_iterator
 263 gsi_start_nondebug (gimple_seq seq)
 264 {
 265   gimple_stmt_iterator gsi = gsi_start (seq);
 266   if (!gsi_end_p (gsi) && is_gimple_debug (gsi_stmt (gsi)))
 267     gsi_next_nondebug (&gsi);
 268
 269   return gsi;
 270 }
 271
 272 /* Return a new iterator pointing to the first non-debug statement in
 273    basic block BB.  */
 274
 275 static inline gimple_stmt_iterator
 276 gsi_start_nondebug_bb (basic_block bb)
 277 {
 278   gimple_stmt_iterator i = gsi_start_bb (bb);
 279
 280   if (!gsi_end_p (i) && is_gimple_debug (gsi_stmt (i)))
 281     gsi_next_nondebug (&i);
 282
 283   return i;
 284 }
 285
 286 /* Return a new iterator pointing to the first non-debug non-label statement in
 287    basic block BB.  */
 288
 289 static inline gimple_stmt_iterator
 290 gsi_start_nondebug_after_labels_bb (basic_block bb)
 291 {
 292   gimple_stmt_iterator i = gsi_after_labels (bb);
 293
 294   if (!gsi_end_p (i) && is_gimple_debug (gsi_stmt (i)))
 295     gsi_next_nondebug (&i);
 296
 297   return i;
 298 }
 299
 300 /* Return a new iterator pointing to the last non-debug statement in
 301    basic block BB.  */
 302
 303 static inline gimple_stmt_iterator
 304 gsi_last_nondebug_bb (basic_block bb)
 305 {
 306   gimple_stmt_iterator i = gsi_last_bb (bb);
 307
 308   if (!gsi_end_p (i) && is_gimple_debug (gsi_stmt (i)))
 309     gsi_prev_nondebug (&i);
 310
 311   return i;
 312 }
 313
 314 /* Return true if I is followed only by debug statements in its
 315    sequence.  */
 316
 317 static inline bool
 318 gsi_one_nondebug_before_end_p (gimple_stmt_iterator i)
 319 {
 320   if (gsi_one_before_end_p (i))
 321     return true;
 322   if (gsi_end_p (i))
 323     return false;
 324   gsi_next_nondebug (&i);
 325   return gsi_end_p (i);
 326 }
 327
 328 /* Advance I statement iterator to the next non-virtual GIMPLE_PHI
 329    statement.  */
 330
 331 static inline void
 332 gsi_next_nonvirtual_phi (gphi_iterator *i)
 333 {
 334   do
 335     {
 336       gsi_next (i);
 337     }
 338   while (!gsi_end_p (*i) && virtual_operand_p (gimple_phi_result (i->phi ())));
 339 }
 340
 341 /* Return a new iterator pointing to the first non-virtual phi statement in
 342    basic block BB.  */
 343
 344 static inline gphi_iterator
 345 gsi_start_nonvirtual_phis (basic_block bb)
 346 {
 347   gphi_iterator i = gsi_start_phis (bb);
 348
 349   if (!gsi_end_p (i) && virtual_operand_p (gimple_phi_result (i.phi ())))
 350     gsi_next_nonvirtual_phi (&i);
 351
 352   return i;
 353 }
 354
 355 /* Return the basic block associated with this iterator.  */
 356
 357 static inline basic_block
 358 gsi_bb (gimple_stmt_iterator i)
 359 {
 360   return i.bb;
 361 }
 362
 363 /* Return the sequence associated with this iterator.  */
 364
 365 static inline gimple_seq
 366 gsi_seq (gimple_stmt_iterator i)
 367 {
 368   return *i.seq;
 369 }
 370
 371 /* Determine whether SEQ is a nondebug singleton.  */
 372
 373 static inline bool
 374 gimple_seq_nondebug_singleton_p (gimple_seq seq)
 375 {
 376   gimple_stmt_iterator gsi;
 377
 378   /* Find a nondebug gimple.  */
 379   gsi.ptr = gimple_seq_first (seq);
 380   gsi.seq = &seq;
 381   gsi.bb = NULL;
 382   while (!gsi_end_p (gsi)
 383          && is_gimple_debug (gsi_stmt (gsi)))
 384     gsi_next (&gsi);
 385
 386   /* No nondebug gimple found, not a singleton.  */
 387   if (gsi_end_p (gsi))
 388     return false;
 389
 390   /* Find a next nondebug gimple.  */
 391   gsi_next (&gsi);
 392   while (!gsi_end_p (gsi)
 393          && is_gimple_debug (gsi_stmt (gsi)))
 394     gsi_next (&gsi);
 395
 396   /* Only a singleton if there's no next nondebug gimple.  */
 397   return gsi_end_p (gsi);
 398 }
 399
 400 #endif /* GCC_GIMPLE_ITERATOR_H */