1 /* Single entry single exit control flow regions.
2 Copyright (C) 2008, 2009 Free Software Foundation, Inc.
3 Contributed by Jan Sjodin <jan.sjodin@amd.com> and
4 Sebastian Pop <sebastian.pop@amd.com>.
6 This file is part of GCC.
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)
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.
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/>. */
25 /* A Single Entry, Single Exit region is a part of the CFG delimited
29 /* Single ENTRY and single EXIT from the SESE region. */
32 /* Parameters used within the SCOP. */
33 VEC (tree, heap) *params;
35 /* Loops completely contained in the SCOP. */
37 VEC (loop_p, heap) *loop_nest;
39 /* Are we allowed to add more params? This is for debugging purpose. We
40 can only add new params before generating the bb domains, otherwise they
45 #define SESE_ENTRY(S) (S->entry)
46 #define SESE_ENTRY_BB(S) (S->entry->dest)
47 #define SESE_EXIT(S) (S->exit)
48 #define SESE_EXIT_BB(S) (S->exit->dest)
49 #define SESE_PARAMS(S) (S->params)
50 #define SESE_LOOPS(S) (S->loops)
51 #define SESE_LOOP_NEST(S) (S->loop_nest)
52 #define SESE_ADD_PARAMS(S) (S->add_params)
54 extern sese new_sese (edge, edge);
55 extern void free_sese (sese);
56 extern void sese_insert_phis_for_liveouts (sese, basic_block, edge, edge);
57 extern void sese_adjust_liveout_phis (sese, htab_t, basic_block, edge, edge);
58 extern void build_sese_loop_nests (sese);
59 extern edge copy_bb_and_scalar_dependences (basic_block, sese, edge, htab_t);
60 extern struct loop *outermost_loop_in_sese (sese, basic_block);
61 extern void insert_loop_close_phis (htab_t, loop_p);
62 extern void insert_guard_phis (basic_block, edge, edge, htab_t, htab_t);
63 extern tree scalar_evolution_in_region (sese, loop_p, tree);
65 /* Check that SESE contains LOOP. */
68 sese_contains_loop (sese sese, struct loop *loop)
70 return bitmap_bit_p (SESE_LOOPS (sese), loop->num);
73 /* The number of parameters in REGION. */
75 static inline unsigned
76 sese_nb_params (sese region)
78 return VEC_length (tree, SESE_PARAMS (region));
81 /* Checks whether BB is contained in the region delimited by ENTRY and
85 bb_in_region (basic_block bb, basic_block entry, basic_block exit)
87 #ifdef ENABLE_CHECKING
92 /* Check that there are no edges coming in the region: all the
93 predecessors of EXIT are dominated by ENTRY. */
94 FOR_EACH_EDGE (e, ei, exit->preds)
95 dominated_by_p (CDI_DOMINATORS, e->src, entry);
97 /* Check that there are no edges going out of the region: the
98 entry is post-dominated by the exit. FIXME: This cannot be
99 checked right now as the CDI_POST_DOMINATORS are needed. */
103 return dominated_by_p (CDI_DOMINATORS, bb, entry)
104 && !(dominated_by_p (CDI_DOMINATORS, bb, exit)
105 && !dominated_by_p (CDI_DOMINATORS, entry, exit));
108 /* Checks whether BB is contained in the region delimited by ENTRY and
112 bb_in_sese_p (basic_block bb, sese region)
114 basic_block entry = SESE_ENTRY_BB (region);
115 basic_block exit = SESE_EXIT_BB (region);
117 return bb_in_region (bb, entry, exit);
120 /* Returns true when NAME is defined in REGION. */
123 defined_in_sese_p (tree name, sese region)
125 gimple stmt = SSA_NAME_DEF_STMT (name);
126 basic_block bb = gimple_bb (stmt);
128 return bb && bb_in_sese_p (bb, region);
131 /* Returns true when LOOP is in REGION. */
134 loop_in_sese_p (struct loop *loop, sese region)
136 return (bb_in_sese_p (loop->header, region)
137 && bb_in_sese_p (loop->latch, region));
140 /* Returns the loop depth of LOOP in REGION. The loop depth
141 is the same as the normal loop depth, but limited by a region.
159 loop_0 does not exist in the region -> invalid
160 loop_1 exists, but is not completely contained in the region -> depth 0
161 loop_2 is completely contained -> depth 1 */
163 static inline unsigned int
164 sese_loop_depth (sese region, loop_p loop)
166 unsigned int depth = 0;
168 gcc_assert ((!loop_in_sese_p (loop, region)
169 && (SESE_ENTRY_BB (region)->loop_father == loop
170 || SESE_EXIT (region)->src->loop_father == loop))
171 || loop_in_sese_p (loop, region));
173 while (loop_in_sese_p (loop, region))
176 loop = loop_outer (loop);
182 /* Splits BB to make a single entry single exit region. */
185 split_region_for_bb (basic_block bb)
189 if (single_pred_p (bb))
190 entry = single_pred_edge (bb);
193 entry = split_block_after_labels (bb);
194 bb = single_succ (bb);
197 if (single_succ_p (bb))
198 exit = single_succ_edge (bb);
201 gimple_stmt_iterator gsi = gsi_last_bb (bb);
203 exit = split_block (bb, gsi_stmt (gsi));
206 return new_sese (entry, exit);
209 /* Returns the block preceding the entry of a SESE. */
211 static inline basic_block
212 block_before_sese (sese sese)
214 return SESE_ENTRY (sese)->src;
219 /* A single entry single exit specialized for conditions. */
221 typedef struct ifsese_s {
227 extern void if_region_set_false_region (ifsese, sese);
228 extern ifsese create_if_region_on_edge (edge, tree);
229 extern ifsese move_sese_in_condition (sese);
230 extern edge get_true_edge_from_guard_bb (basic_block);
231 extern edge get_false_edge_from_guard_bb (basic_block);
234 if_region_entry (ifsese if_region)
236 return SESE_ENTRY (if_region->region);
240 if_region_exit (ifsese if_region)
242 return SESE_EXIT (if_region->region);
245 static inline basic_block
246 if_region_get_condition_block (ifsese if_region)
248 return if_region_entry (if_region)->dest;
251 /* Structure containing the mapping between the old names and the new
252 names used after block copy in the new loop context. */
253 typedef struct rename_map_elt_s
258 DEF_VEC_P(rename_map_elt);
259 DEF_VEC_ALLOC_P (rename_map_elt, heap);
261 extern void debug_rename_map (htab_t);
262 extern hashval_t rename_map_elt_info (const void *);
263 extern int eq_rename_map_elts (const void *, const void *);
264 extern void set_rename (htab_t, tree, tree);
265 extern void rename_nb_iterations (htab_t);
267 /* Constructs a new SCEV_INFO_STR structure for VAR and INSTANTIATED_BELOW. */
269 static inline rename_map_elt
270 new_rename_map_elt (tree old_name, tree expr)
274 res = XNEW (struct rename_map_elt_s);
275 res->old_name = old_name;
281 /* Structure containing the mapping between the CLooG's induction
282 variable and the type of the old induction variable. */
283 typedef struct ivtype_map_elt_s
286 const char *cloog_iv;
289 extern void debug_ivtype_map (htab_t);
290 extern hashval_t ivtype_map_elt_info (const void *);
291 extern int eq_ivtype_map_elts (const void *, const void *);
293 /* Constructs a new SCEV_INFO_STR structure for VAR and INSTANTIATED_BELOW. */
295 static inline ivtype_map_elt
296 new_ivtype_map_elt (const char *cloog_iv, tree type)
300 res = XNEW (struct ivtype_map_elt_s);
301 res->cloog_iv = cloog_iv;
307 /* Free and compute again all the dominators information. */
310 recompute_all_dominators (void)
312 mark_irreducible_loops ();
313 free_dominance_info (CDI_DOMINATORS);
314 free_dominance_info (CDI_POST_DOMINATORS);
315 calculate_dominance_info (CDI_DOMINATORS);
316 calculate_dominance_info (CDI_POST_DOMINATORS);
319 typedef struct gimple_bb
323 /* Lists containing the restrictions of the conditional statements
324 dominating this bb. This bb can only be executed, if all conditions
329 for (i = 0; i <= 20; i++)
337 So for B there is an additional condition (2i <= 8).
339 List of COND_EXPR and SWITCH_EXPR. A COND_EXPR is true only if the
340 corresponding element in CONDITION_CASES is not NULL_TREE. For a
341 SWITCH_EXPR the corresponding element in CONDITION_CASES is a
343 VEC (gimple, heap) *conditions;
344 VEC (gimple, heap) *condition_cases;
345 VEC (data_reference_p, heap) *data_refs;
346 htab_t cloog_iv_types;
349 #define GBB_BB(GBB) GBB->bb
350 #define GBB_DATA_REFS(GBB) GBB->data_refs
351 #define GBB_CONDITIONS(GBB) GBB->conditions
352 #define GBB_CONDITION_CASES(GBB) GBB->condition_cases
353 #define GBB_CLOOG_IV_TYPES(GBB) GBB->cloog_iv_types
355 /* Return the innermost loop that contains the basic block GBB. */
357 static inline struct loop *
358 gbb_loop (struct gimple_bb *gbb)
360 return GBB_BB (gbb)->loop_father;
363 /* Returns the gimple loop, that corresponds to the loop_iterator_INDEX.
364 If there is no corresponding gimple loop, we return NULL. */
367 gbb_loop_at_index (gimple_bb_p gbb, sese region, int index)
369 loop_p loop = gbb_loop (gbb);
370 int depth = sese_loop_depth (region, loop);
372 while (--depth > index)
373 loop = loop_outer (loop);
375 gcc_assert (sese_contains_loop (region, loop));
380 /* The number of common loops in REGION for GBB1 and GBB2. */
383 nb_common_loops (sese region, gimple_bb_p gbb1, gimple_bb_p gbb2)
385 loop_p l1 = gbb_loop (gbb1);
386 loop_p l2 = gbb_loop (gbb2);
387 loop_p common = find_common_loop (l1, l2);
389 return sese_loop_depth (region, common);
392 extern void print_gimple_bb (FILE *, gimple_bb_p, int, int);
393 extern void debug_gbb (gimple_bb_p, int);