gcc/tree-affine.h

   1 /* Operations with affine combinations of trees.
   2    Copyright (C) 2005 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it
   7 under the terms of the GNU General Public License as published by the
   8 Free Software Foundation; either version 2, or (at your option) any
   9 later version.
  10
  11 GCC is distributed in the hope that it will be useful, but WITHOUT
  12 ANY 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.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING.  If not, write to the Free
  18 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
  19 02110-1301, USA.  */
  20
  21 /* Affine combination of trees.  We keep track of at most MAX_AFF_ELTS elements
  22    to make things simpler; this is sufficient in most cases.  */
  23
  24 #define MAX_AFF_ELTS 8
  25
  26 /* Element of an affine combination.  */
  27
  28 struct aff_comb_elt
  29 {
  30   /* The value of the element.  */
  31   tree val;
  32
  33   /* Its coefficient in the combination.  */
  34   double_int coef;
  35 };
  36
  37 typedef struct affine_tree_combination
  38 {
  39   /* Type of the result of the combination.  */
  40   tree type;
  41
  42   /* Constant offset.  */
  43   double_int offset;
  44
  45   /* Number of elements of the combination.  */
  46   unsigned n;
  47
  48   /* Elements and their coefficients.  Type of elements may be different from
  49      TYPE, but their sizes must be the same (STRIP_NOPS is applied to the
  50      elements).
  51
  52      The coefficients are always sign extended from the precision of TYPE
  53      (regardless of signedness of TYPE).  */
  54   struct aff_comb_elt elts[MAX_AFF_ELTS];
  55
  56   /* Remainder of the expression.  Usually NULL, used only if there are more
  57      than MAX_AFF_ELTS elements.  Type of REST must be TYPE.  */
  58   tree rest;
  59 } aff_tree;
  60
  61 double_int double_int_ext_for_comb (double_int, aff_tree *);
  62 void aff_combination_const (aff_tree *, tree, double_int);
  63 void aff_combination_elt (aff_tree *, tree, tree);
  64 void aff_combination_scale (aff_tree *, double_int);
  65 void aff_combination_add (aff_tree *, aff_tree *);
  66 void aff_combination_add_elt (aff_tree *, tree, double_int);
  67 void aff_combination_remove_elt (aff_tree *, unsigned);
  68 void aff_combination_convert (aff_tree *, tree);
  69 void tree_to_aff_combination (tree, tree, aff_tree *);
  70 tree aff_combination_to_tree (aff_tree *);
  71 void unshare_aff_combination (aff_tree *);