1/* Operations with affine combinations of trees.
2   Copyright (C) 2005, 2007, 2008 Free Software Foundation, Inc.
3
4This file is part of GCC.
5
6GCC is free software; you can redistribute it and/or modify it
7under the terms of the GNU General Public License as published by the
8Free Software Foundation; either version 3, or (at your option) any
9later version.
10
11GCC is distributed in the hope that it will be useful, but WITHOUT
12ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14for more details.
15
16You should have received a copy of the GNU General Public License
17along with GCC; see the file COPYING3.  If not see
18<http://www.gnu.org/licenses/>.  */
19
20/* Affine combination of trees.  We keep track of at most MAX_AFF_ELTS elements
21   to make things simpler; this is sufficient in most cases.  */
22
23#define MAX_AFF_ELTS 8
24
25/* Element of an affine combination.  */
26
27struct aff_comb_elt
28{
29  /* The value of the element.  */
30  tree val;
31
32  /* Its coefficient in the combination.  */
33  double_int coef;
34};
35
36typedef struct affine_tree_combination
37{
38  /* Type of the result of the combination.  */
39  tree type;
40
41  /* Constant offset.  */
42  double_int offset;
43
44  /* Number of elements of the combination.  */
45  unsigned n;
46
47  /* Elements and their coefficients.  Type of elements may be different from
48     TYPE, but their sizes must be the same (STRIP_NOPS is applied to the
49     elements).
50
51     The coefficients are always sign extended from the precision of TYPE
52     (regardless of signedness of TYPE).  */
53  struct aff_comb_elt elts[MAX_AFF_ELTS];
54
55  /* Remainder of the expression.  Usually NULL, used only if there are more
56     than MAX_AFF_ELTS elements.  Type of REST will be either sizetype for
57     TYPE of POINTER_TYPEs or TYPE.  */
58  tree rest;
59} aff_tree;
60
61double_int double_int_ext_for_comb (double_int, aff_tree *);
62void aff_combination_const (aff_tree *, tree, double_int);
63void aff_combination_elt (aff_tree *, tree, tree);
64void aff_combination_scale (aff_tree *, double_int);
65void aff_combination_mult (aff_tree *, aff_tree *, aff_tree *);
66void aff_combination_add (aff_tree *, aff_tree *);
67void aff_combination_add_elt (aff_tree *, tree, double_int);
68void aff_combination_remove_elt (aff_tree *, unsigned);
69void aff_combination_convert (aff_tree *, tree);
70void tree_to_aff_combination (tree, tree, aff_tree *);
71tree aff_combination_to_tree (aff_tree *);
72void unshare_aff_combination (aff_tree *);
73bool aff_combination_constant_multiple_p (aff_tree *, aff_tree *, double_int *);
74void aff_combination_expand (aff_tree *, struct pointer_map_t **);
75void tree_to_aff_combination_expand (tree, tree, aff_tree *,
76				     struct pointer_map_t **);
77void get_inner_reference_aff (tree, aff_tree *, double_int *);
78void free_affine_expand_cache (struct pointer_map_t **);
79
80/* Debugging functions.  */
81void print_aff (FILE *, aff_tree *);
82void debug_aff (aff_tree *);
83