1 /* Single entry single exit control flow regions.
2 Copyright (C) 2008-2015 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 typedef hash_map
<basic_block
, vec
<basic_block
> > bb_map_t
;
26 typedef hash_map
<tree
, vec
<tree
> > rename_map_t
;
27 typedef struct ifsese_s
*ifsese
;
28 /* First phi is the new codegenerated phi second one is original phi. */
29 typedef std::pair
<gphi
*, gphi
*> phi_rename
;
30 /* First edge is the init edge and second is the back edge w.r.t. a loop. */
31 typedef std::pair
<edge
, edge
> init_back_edge_pair_t
;
33 /* A Single Entry, Single Exit region is a part of the CFG delimited
37 sese_l (edge e
, edge x
) : entry (e
), exit (x
) {}
39 operator bool () const { return entry
&& exit
; }
45 /* Get the entry of an sese S. */
47 static inline basic_block
48 get_entry_bb (sese_l
&s
)
53 /* Get the exit of an sese S. */
55 static inline basic_block
56 get_exit_bb (sese_l
&s
)
61 /* Returns the index of V where ELEM can be found. -1 Otherwise. */
65 vec_find (const vec
<T
> &v
, const T
&elem
)
69 FOR_EACH_VEC_ELT (v
, i
, t
)
75 /* A helper structure for bookkeeping information about a scop in graphite. */
76 typedef struct sese_info_t
78 /* The SESE region. */
81 /* Parameters used within the SCOP. */
84 /* Maps an old name to one or more new names. When there are several new
85 names, one has to select the definition corresponding to the immediate
87 rename_map_t
*rename_map
;
89 /* Loops completely contained in this SESE. */
91 vec
<loop_p
> loop_nest
;
93 /* Basic blocks contained in this SESE. */
96 /* Copied basic blocks indexed by the original bb. */
97 bb_map_t
*copied_bb_map
;
99 /* A vector of phi nodes to be updated when all arguments are available. The
100 pair contains first the old_phi and second the new_phi. */
101 vec
<phi_rename
> incomplete_phis
;
103 /* The condition region generated for this sese. */
108 extern sese_info_p
new_sese_info (edge
, edge
);
109 extern void free_sese_info (sese_info_p
);
110 extern void sese_insert_phis_for_liveouts (sese_info_p
, basic_block
, edge
, edge
);
111 extern void build_sese_loop_nests (sese_info_p
);
112 extern edge
copy_bb_and_scalar_dependences (basic_block
, sese_info_p
, edge
,
114 extern struct loop
*outermost_loop_in_sese (sese_l
&, basic_block
);
115 extern tree
scalar_evolution_in_region (sese_l
&, loop_p
, tree
);
116 extern bool invariant_in_sese_p_rec (tree
, sese_l
&, bool *);
117 extern bool bb_contains_loop_phi_nodes (basic_block
);
118 extern bool bb_contains_loop_close_phi_nodes (basic_block
);
119 extern std::pair
<edge
, edge
> get_edges (basic_block bb
);
120 extern void copy_loop_phi_args (gphi
*, init_back_edge_pair_t
&,
121 gphi
*, init_back_edge_pair_t
&,
123 extern bool copy_loop_close_phi_args (basic_block
, basic_block
,
125 extern bool copy_cond_phi_args (gphi
*, gphi
*, vec
<tree
>,
128 /* Check that SESE contains LOOP. */
131 sese_contains_loop (sese_info_p sese
, struct loop
*loop
)
133 return bitmap_bit_p (sese
->loops
, loop
->num
);
136 /* The number of parameters in REGION. */
138 static inline unsigned
139 sese_nb_params (sese_info_p region
)
141 return region
->params
.length ();
144 /* Checks whether BB is contained in the region delimited by ENTRY and
148 bb_in_region (basic_block bb
, basic_block entry
, basic_block exit
)
150 /* FIXME: PR67842. */
157 /* Check that there are no edges coming in the region: all the
158 predecessors of EXIT are dominated by ENTRY. */
159 FOR_EACH_EDGE (e
, ei
, exit
->preds
)
160 gcc_assert (dominated_by_p (CDI_DOMINATORS
, e
->src
, entry
));
164 return dominated_by_p (CDI_DOMINATORS
, bb
, entry
)
165 && !(dominated_by_p (CDI_DOMINATORS
, bb
, exit
)
166 && !dominated_by_p (CDI_DOMINATORS
, entry
, exit
));
169 /* Checks whether BB is contained in the region delimited by ENTRY and
173 bb_in_sese_p (basic_block bb
, sese_l
&r
)
175 return bb_in_region (bb
, r
.entry
->dest
, r
.exit
->dest
);
178 /* Returns true when STMT is defined in REGION. */
181 stmt_in_sese_p (gimple
*stmt
, sese_l
&r
)
183 basic_block bb
= gimple_bb (stmt
);
184 return bb
&& bb_in_sese_p (bb
, r
);
187 /* Returns true when NAME is defined in REGION. */
190 defined_in_sese_p (tree name
, sese_l
&r
)
192 return stmt_in_sese_p (SSA_NAME_DEF_STMT (name
), r
);
195 /* Returns true when LOOP is in REGION. */
198 loop_in_sese_p (struct loop
*loop
, sese_l
®ion
)
200 return (bb_in_sese_p (loop
->header
, region
)
201 && bb_in_sese_p (loop
->latch
, region
));
204 /* Returns the loop depth of LOOP in REGION. The loop depth
205 is the same as the normal loop depth, but limited by a region.
223 loop_0 does not exist in the region -> invalid
224 loop_1 exists, but is not completely contained in the region -> depth 0
225 loop_2 is completely contained -> depth 1 */
227 static inline unsigned int
228 sese_loop_depth (sese_l
®ion
, loop_p loop
)
230 unsigned int depth
= 0;
232 while (loop_in_sese_p (loop
, region
))
235 loop
= loop_outer (loop
);
241 /* A single entry single exit specialized for conditions. */
243 typedef struct ifsese_s
{
245 sese_info_p true_region
;
246 sese_info_p false_region
;
249 extern void if_region_set_false_region (ifsese
, sese_info_p
);
250 extern ifsese
move_sese_in_condition (sese_info_p
);
251 extern edge
get_true_edge_from_guard_bb (basic_block
);
252 extern edge
get_false_edge_from_guard_bb (basic_block
);
253 extern void set_ifsese_condition (ifsese
, tree
);
256 if_region_entry (ifsese if_region
)
258 return if_region
->region
->region
.entry
;
262 if_region_exit (ifsese if_region
)
264 return if_region
->region
->region
.exit
;
267 static inline basic_block
268 if_region_get_condition_block (ifsese if_region
)
270 return if_region_entry (if_region
)->dest
;
273 /* Free and compute again all the dominators information. */
276 recompute_all_dominators (void)
278 mark_irreducible_loops ();
279 free_dominance_info (CDI_DOMINATORS
);
280 calculate_dominance_info (CDI_DOMINATORS
);
282 free_dominance_info (CDI_POST_DOMINATORS
);
283 calculate_dominance_info (CDI_POST_DOMINATORS
);
286 typedef std::pair
<gimple
*, tree
> scalar_use
;
288 typedef struct gimple_poly_bb
293 /* Lists containing the restrictions of the conditional statements
294 dominating this bb. This bb can only be executed, if all conditions
299 for (i = 0; i <= 20; i++)
307 So for B there is an additional condition (2i <= 8).
309 List of COND_EXPR and SWITCH_EXPR. A COND_EXPR is true only if the
310 corresponding element in CONDITION_CASES is not NULL_TREE. For a
311 SWITCH_EXPR the corresponding element in CONDITION_CASES is a
313 vec
<gimple
*> conditions
;
314 vec
<gimple
*> condition_cases
;
315 vec
<data_reference_p
> data_refs
;
316 vec
<scalar_use
> read_scalar_refs
;
317 vec
<tree
> write_scalar_refs
;
320 #define GBB_BB(GBB) (GBB)->bb
321 #define GBB_PBB(GBB) (GBB)->pbb
322 #define GBB_DATA_REFS(GBB) (GBB)->data_refs
323 #define GBB_CONDITIONS(GBB) (GBB)->conditions
324 #define GBB_CONDITION_CASES(GBB) (GBB)->condition_cases
326 /* Return the innermost loop that contains the basic block GBB. */
328 static inline struct loop
*
329 gbb_loop (gimple_poly_bb_p gbb
)
331 return GBB_BB (gbb
)->loop_father
;
334 /* Returns the gimple loop, that corresponds to the loop_iterator_INDEX.
335 If there is no corresponding gimple loop, we return NULL. */
338 gbb_loop_at_index (gimple_poly_bb_p gbb
, sese_l
®ion
, int index
)
340 loop_p loop
= gbb_loop (gbb
);
341 int depth
= sese_loop_depth (region
, loop
);
343 while (--depth
> index
)
344 loop
= loop_outer (loop
);
346 gcc_assert (loop_in_sese_p (loop
, region
));
351 /* The number of common loops in REGION for GBB1 and GBB2. */
354 nb_common_loops (sese_l
®ion
, gimple_poly_bb_p gbb1
, gimple_poly_bb_p gbb2
)
356 loop_p l1
= gbb_loop (gbb1
);
357 loop_p l2
= gbb_loop (gbb2
);
358 loop_p common
= find_common_loop (l1
, l2
);
360 return sese_loop_depth (region
, common
);
363 /* Return true when DEF can be analyzed in REGION by the scalar
364 evolution analyzer. */
367 scev_analyzable_p (tree def
, sese_l
®ion
)
371 tree type
= TREE_TYPE (def
);
373 /* When Graphite generates code for a scev, the code generator
374 expresses the scev in function of a single induction variable.
375 This is unsafe for floating point computations, as it may replace
376 a floating point sum reduction with a multiplication. The
377 following test returns false for non integer types to avoid such
379 if (!INTEGRAL_TYPE_P (type
)
380 && !POINTER_TYPE_P (type
))
383 loop
= loop_containing_stmt (SSA_NAME_DEF_STMT (def
));
384 scev
= scalar_evolution_in_region (region
, loop
, def
);
386 return !chrec_contains_undetermined (scev
)
387 && (TREE_CODE (scev
) != SSA_NAME
388 || !defined_in_sese_p (scev
, region
))
389 && (tree_does_not_contain_chrecs (scev
)
390 || evolution_function_is_affine_p (scev
));