/* Operations with affine combinations of trees. | |

Copyright (C) 2005-2020 Free Software Foundation, Inc. | |

This file is part of GCC. | |

GCC is free software; you can redistribute it and/or modify it | |

under the terms of the GNU General Public License as published by the | |

Free Software Foundation; either version 3, or (at your option) any | |

later version. | |

GCC is distributed in the hope that it will be useful, but WITHOUT | |

ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |

FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |

for more details. | |

You should have received a copy of the GNU General Public License | |

along with GCC; see the file COPYING3. If not see | |

<http://www.gnu.org/licenses/>. */ | |

/* Affine combination of trees. We keep track of at most MAX_AFF_ELTS elements | |

to make things simpler; this is sufficient in most cases. */ | |

#ifndef GCC_TREE_AFFINE_H | |

#define GCC_TREE_AFFINE_H | |

#define MAX_AFF_ELTS 8 | |

/* Element of an affine combination. */ | |

class aff_comb_elt | |

{ | |

public: | |

/* The value of the element. */ | |

tree val; | |

/* Its coefficient in the combination. */ | |

widest_int coef; | |

}; | |

class aff_tree | |

{ | |

public: | |

/* Type of the result of the combination. */ | |

tree type; | |

/* Constant offset. */ | |

poly_widest_int offset; | |

/* Number of elements of the combination. */ | |

unsigned n; | |

/* Elements and their coefficients. Type of elements may be different from | |

TYPE, but their sizes must be the same (STRIP_NOPS is applied to the | |

elements). | |

The coefficients are always sign extended from the precision of TYPE | |

(regardless of signedness of TYPE). */ | |

class aff_comb_elt elts[MAX_AFF_ELTS]; | |

/* Remainder of the expression. Usually NULL, used only if there are more | |

than MAX_AFF_ELTS elements. Type of REST will be either sizetype for | |

TYPE of POINTER_TYPEs or TYPE. */ | |

tree rest; | |

}; | |

class name_expansion; | |

void aff_combination_const (aff_tree *, tree, const poly_widest_int &); | |

void aff_combination_elt (aff_tree *, tree, tree); | |

void aff_combination_scale (aff_tree *, const widest_int &); | |

void aff_combination_mult (aff_tree *, aff_tree *, aff_tree *); | |

void aff_combination_add (aff_tree *, aff_tree *); | |

void aff_combination_add_elt (aff_tree *, tree, const widest_int &); | |

void aff_combination_remove_elt (aff_tree *, unsigned); | |

void aff_combination_convert (aff_tree *, tree); | |

void tree_to_aff_combination (tree, tree, aff_tree *); | |

tree aff_combination_to_tree (aff_tree *); | |

void unshare_aff_combination (aff_tree *); | |

bool aff_combination_constant_multiple_p (aff_tree *, aff_tree *, | |

poly_widest_int *); | |

void aff_combination_expand (aff_tree *, hash_map<tree, name_expansion *> **); | |

void tree_to_aff_combination_expand (tree, tree, aff_tree *, | |

hash_map<tree, name_expansion *> **); | |

tree get_inner_reference_aff (tree, aff_tree *, poly_widest_int *); | |

void free_affine_expand_cache (hash_map<tree, name_expansion *> **); | |

bool aff_comb_cannot_overlap_p (aff_tree *, const poly_widest_int &, | |

const poly_widest_int &); | |

/* Debugging functions. */ | |

void debug_aff (aff_tree *); | |

/* Return AFF's type. */ | |

inline tree | |

aff_combination_type (aff_tree *aff) | |

{ | |

return aff->type; | |

} | |

/* Return true if AFF is actually ZERO. */ | |

inline bool | |

aff_combination_zero_p (aff_tree *aff) | |

{ | |

if (!aff) | |

return true; | |

if (aff->n == 0 && known_eq (aff->offset, 0)) | |

return true; | |

return false; | |

} | |

/* Return true if AFF is actually const. */ | |

inline bool | |

aff_combination_const_p (aff_tree *aff) | |

{ | |

return (aff == NULL || aff->n == 0); | |

} | |

/* Return true iff AFF contains one (negated) singleton variable. Users need | |

to make sure AFF points to a valid combination. */ | |

inline bool | |

aff_combination_singleton_var_p (aff_tree *aff) | |

{ | |

return (aff->n == 1 | |

&& known_eq (aff->offset, 0) | |

&& (aff->elts[0].coef == 1 || aff->elts[0].coef == -1)); | |

} | |

#endif /* GCC_TREE_AFFINE_H */ |