* combine.c (try_combine): Prefer to delete dead SETs inside
[official-gcc.git] / gcc / gimple-iterator.h
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1 /* Header file for gimple iterators.
2 Copyright (C) 2013-2014 Free Software Foundation, Inc.
4 This file is part of GCC.
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.
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.
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/>. */
20 #ifndef GCC_GIMPLE_ITERATOR_H
21 #define GCC_GIMPLE_ITERATOR_H
23 /* Iterator object for GIMPLE statement sequences. */
25 struct gimple_stmt_iterator
27 /* Sequence node holding the current statement. */
28 gimple_seq_node ptr;
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;
38 /* Iterator over GIMPLE_PHI statements. */
39 struct gphi_iterator : public gimple_stmt_iterator
41 gphi *phi () const
43 return as_a <gphi *> (ptr);
47 enum gsi_iterator_update
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. */
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);
94 /* Return a new iterator pointing to GIMPLE_SEQ's first statement. */
96 static inline gimple_stmt_iterator
97 gsi_start_1 (gimple_seq *seq)
99 gimple_stmt_iterator i;
101 i.ptr = gimple_seq_first (*seq);
102 i.seq = seq;
103 i.bb = i.ptr ? gimple_bb (i.ptr) : NULL;
105 return i;
108 #define gsi_start(x) gsi_start_1 (&(x))
110 static inline gimple_stmt_iterator
111 gsi_none (void)
113 gimple_stmt_iterator i;
114 i.ptr = NULL;
115 i.seq = NULL;
116 i.bb = NULL;
117 return i;
120 /* Return a new iterator pointing to the first statement in basic block BB. */
122 static inline gimple_stmt_iterator
123 gsi_start_bb (basic_block bb)
125 gimple_stmt_iterator i;
126 gimple_seq *seq;
128 seq = bb_seq_addr (bb);
129 i.ptr = gimple_seq_first (*seq);
130 i.seq = seq;
131 i.bb = bb;
133 return i;
136 gimple_stmt_iterator gsi_start_edge (edge e);
138 /* Return a new iterator initially pointing to GIMPLE_SEQ's last statement. */
140 static inline gimple_stmt_iterator
141 gsi_last_1 (gimple_seq *seq)
143 gimple_stmt_iterator i;
145 i.ptr = gimple_seq_last (*seq);
146 i.seq = seq;
147 i.bb = i.ptr ? gimple_bb (i.ptr) : NULL;
149 return i;
152 #define gsi_last(x) gsi_last_1 (&(x))
154 /* Return a new iterator pointing to the last statement in basic block BB. */
156 static inline gimple_stmt_iterator
157 gsi_last_bb (basic_block bb)
159 gimple_stmt_iterator i;
160 gimple_seq *seq;
162 seq = bb_seq_addr (bb);
163 i.ptr = gimple_seq_last (*seq);
164 i.seq = seq;
165 i.bb = bb;
167 return i;
170 /* Return true if I is at the end of its sequence. */
172 static inline bool
173 gsi_end_p (gimple_stmt_iterator i)
175 return i.ptr == NULL;
178 /* Return true if I is one statement before the end of its sequence. */
180 static inline bool
181 gsi_one_before_end_p (gimple_stmt_iterator i)
183 return i.ptr != NULL && i.ptr->next == NULL;
186 /* Advance the iterator to the next gimple statement. */
188 static inline void
189 gsi_next (gimple_stmt_iterator *i)
191 i->ptr = i->ptr->next;
194 /* Advance the iterator to the previous gimple statement. */
196 static inline void
197 gsi_prev (gimple_stmt_iterator *i)
199 gimple prev = i->ptr->prev;
200 if (prev->next)
201 i->ptr = prev;
202 else
203 i->ptr = NULL;
206 /* Return the current stmt. */
208 static inline gimple
209 gsi_stmt (gimple_stmt_iterator i)
211 return i.ptr;
214 /* Return a block statement iterator that points to the first non-label
215 statement in block BB. */
217 static inline gimple_stmt_iterator
218 gsi_after_labels (basic_block bb)
220 gimple_stmt_iterator gsi = gsi_start_bb (bb);
222 while (!gsi_end_p (gsi) && gimple_code (gsi_stmt (gsi)) == GIMPLE_LABEL)
223 gsi_next (&gsi);
225 return gsi;
228 /* Advance the iterator to the next non-debug gimple statement. */
230 static inline void
231 gsi_next_nondebug (gimple_stmt_iterator *i)
235 gsi_next (i);
237 while (!gsi_end_p (*i) && is_gimple_debug (gsi_stmt (*i)));
240 /* Advance the iterator to the next non-debug gimple statement. */
242 static inline void
243 gsi_prev_nondebug (gimple_stmt_iterator *i)
247 gsi_prev (i);
249 while (!gsi_end_p (*i) && is_gimple_debug (gsi_stmt (*i)));
252 /* Return a new iterator pointing to the first non-debug statement in
253 basic block BB. */
255 static inline gimple_stmt_iterator
256 gsi_start_nondebug_bb (basic_block bb)
258 gimple_stmt_iterator i = gsi_start_bb (bb);
260 if (!gsi_end_p (i) && is_gimple_debug (gsi_stmt (i)))
261 gsi_next_nondebug (&i);
263 return i;
266 /* Return a new iterator pointing to the first non-debug non-label statement in
267 basic block BB. */
269 static inline gimple_stmt_iterator
270 gsi_start_nondebug_after_labels_bb (basic_block bb)
272 gimple_stmt_iterator i = gsi_after_labels (bb);
274 if (!gsi_end_p (i) && is_gimple_debug (gsi_stmt (i)))
275 gsi_next_nondebug (&i);
277 return i;
280 /* Return a new iterator pointing to the last non-debug statement in
281 basic block BB. */
283 static inline gimple_stmt_iterator
284 gsi_last_nondebug_bb (basic_block bb)
286 gimple_stmt_iterator i = gsi_last_bb (bb);
288 if (!gsi_end_p (i) && is_gimple_debug (gsi_stmt (i)))
289 gsi_prev_nondebug (&i);
291 return i;
294 /* Iterates I statement iterator to the next non-virtual statement. */
296 static inline void
297 gsi_next_nonvirtual_phi (gphi_iterator *i)
299 gphi *phi;
301 if (gsi_end_p (*i))
302 return;
304 phi = i->phi ();
305 gcc_assert (phi != NULL);
307 while (virtual_operand_p (gimple_phi_result (phi)))
309 gsi_next (i);
311 if (gsi_end_p (*i))
312 return;
314 phi = i->phi ();
318 /* Return the basic block associated with this iterator. */
320 static inline basic_block
321 gsi_bb (gimple_stmt_iterator i)
323 return i.bb;
326 /* Return the sequence associated with this iterator. */
328 static inline gimple_seq
329 gsi_seq (gimple_stmt_iterator i)
331 return *i.seq;
334 #endif /* GCC_GIMPLE_ITERATOR_H */