1/* Scalar evolution detector.
2   Copyright (C) 2003-2015 Free Software Foundation, Inc.
3   Contributed by Sebastian Pop <s.pop@laposte.net>
4
5This file is part of GCC.
6
7GCC is free software; you can redistribute it and/or modify it under
8the terms of the GNU General Public License as published by the Free
9Software Foundation; either version 3, or (at your option) any later
10version.
11
12GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13WARRANTY; without even the implied warranty of MERCHANTABILITY or
14FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
15for more details.
16
17You should have received a copy of the GNU General Public License
18along with GCC; see the file COPYING3.  If not see
19<http://www.gnu.org/licenses/>.  */
20
21#ifndef GCC_TREE_SCALAR_EVOLUTION_H
22#define GCC_TREE_SCALAR_EVOLUTION_H
23
24extern tree number_of_latch_executions (struct loop *);
25extern gcond *get_loop_exit_condition (const struct loop *);
26
27extern void scev_initialize (void);
28extern bool scev_initialized_p (void);
29extern void scev_reset (void);
30extern void scev_reset_htab (void);
31extern void scev_finalize (void);
32extern tree analyze_scalar_evolution (struct loop *, tree);
33extern tree instantiate_scev (basic_block, struct loop *, tree);
34extern tree resolve_mixers (struct loop *, tree);
35extern void gather_stats_on_scev_database (void);
36extern unsigned int scev_const_prop (void);
37extern bool expression_expensive_p (tree);
38extern bool simple_iv (struct loop *, struct loop *, tree, struct affine_iv *,
39		       bool);
40extern tree compute_overall_effect_of_inner_loop (struct loop *, tree);
41
42/* Returns the basic block preceding LOOP, or the CFG entry block when
43   the loop is function's body.  */
44
45static inline basic_block
46block_before_loop (loop_p loop)
47{
48  edge preheader = loop_preheader_edge (loop);
49  return (preheader ? preheader->src : ENTRY_BLOCK_PTR_FOR_FN (cfun));
50}
51
52/* Analyze all the parameters of the chrec that were left under a
53   symbolic form.  LOOP is the loop in which symbolic names have to
54   be analyzed and instantiated.  */
55
56static inline tree
57instantiate_parameters (struct loop *loop, tree chrec)
58{
59  return instantiate_scev (block_before_loop (loop), loop, chrec);
60}
61
62/* Returns the loop of the polynomial chrec CHREC.  */
63
64static inline struct loop *
65get_chrec_loop (const_tree chrec)
66{
67  return get_loop (cfun, CHREC_VARIABLE (chrec));
68}
69
70#endif  /* GCC_TREE_SCALAR_EVOLUTION_H  */
71