| /* Chains of recurrences. |
| Copyright (C) 2003-2019 Free Software Foundation, Inc. |
| Contributed by Sebastian Pop <pop@cri.ensmp.fr> |
| |
| 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/>. */ |
| |
| #ifndef GCC_TREE_CHREC_H |
| #define GCC_TREE_CHREC_H |
| |
| /* The following trees are unique elements. Thus the comparison of another |
| element to these elements should be done on the pointer to these trees, |
| and not on their value. */ |
| |
| extern tree chrec_not_analyzed_yet; |
| extern GTY(()) tree chrec_dont_know; |
| extern GTY(()) tree chrec_known; |
| |
| /* After having added an automatically generated element, please |
| include it in the following function. */ |
| |
| static inline bool |
| automatically_generated_chrec_p (const_tree chrec) |
| { |
| return (chrec == chrec_dont_know |
| || chrec == chrec_known); |
| } |
| |
| /* The tree nodes aka. CHRECs. */ |
| |
| static inline bool |
| tree_is_chrec (const_tree expr) |
| { |
| if (TREE_CODE (expr) == POLYNOMIAL_CHREC |
| || automatically_generated_chrec_p (expr)) |
| return true; |
| else |
| return false; |
| } |
| |
| |
| enum ev_direction {EV_DIR_GROWS, EV_DIR_DECREASES, EV_DIR_UNKNOWN}; |
| enum ev_direction scev_direction (const_tree); |
| |
| /* Chrec folding functions. */ |
| extern tree chrec_fold_plus (tree, tree, tree); |
| extern tree chrec_fold_minus (tree, tree, tree); |
| extern tree chrec_fold_multiply (tree, tree, tree); |
| extern tree chrec_convert (tree, tree, gimple *, bool = true, tree = NULL); |
| extern tree chrec_convert_rhs (tree, tree, gimple *); |
| extern tree chrec_convert_aggressive (tree, tree, bool *); |
| |
| /* Operations. */ |
| extern tree chrec_apply (unsigned, tree, tree); |
| extern tree chrec_apply_map (tree, vec<tree> ); |
| extern tree chrec_replace_initial_condition (tree, tree); |
| extern tree initial_condition (tree); |
| extern tree initial_condition_in_loop_num (tree, unsigned); |
| extern tree evolution_part_in_loop_num (tree, unsigned); |
| extern tree hide_evolution_in_other_loops_than_loop (tree, unsigned); |
| extern tree reset_evolution_in_loop (unsigned, tree, tree); |
| extern tree chrec_merge (tree, tree); |
| extern void for_each_scev_op (tree *, bool (*) (tree *, void *), void *); |
| extern bool convert_affine_scev (struct loop *, tree, tree *, tree *, gimple *, |
| bool, tree = NULL); |
| |
| /* Observers. */ |
| extern bool eq_evolutions_p (const_tree, const_tree); |
| extern bool is_multivariate_chrec (const_tree); |
| extern bool chrec_contains_symbols (const_tree, struct loop * = NULL); |
| extern bool chrec_contains_symbols_defined_in_loop (const_tree, unsigned); |
| extern bool chrec_contains_undetermined (const_tree); |
| extern bool tree_contains_chrecs (const_tree, int *); |
| extern bool evolution_function_is_affine_multivariate_p (const_tree, int); |
| extern bool evolution_function_is_univariate_p (const_tree, int = 0); |
| extern unsigned nb_vars_in_chrec (tree); |
| extern bool evolution_function_is_invariant_p (tree, int); |
| extern bool scev_is_linear_expression (tree); |
| extern bool evolution_function_right_is_integer_cst (const_tree); |
| |
| /* Determines whether CHREC is equal to zero. */ |
| |
| static inline bool |
| chrec_zerop (const_tree chrec) |
| { |
| if (chrec == NULL_TREE) |
| return false; |
| |
| if (TREE_CODE (chrec) == INTEGER_CST) |
| return integer_zerop (chrec); |
| |
| return false; |
| } |
| |
| /* Determines whether CHREC is a loop invariant with respect to LOOP_NUM. |
| Set the result in RES and return true when the property can be computed. */ |
| |
| static inline bool |
| no_evolution_in_loop_p (tree chrec, unsigned loop_num, bool *res) |
| { |
| tree scev; |
| |
| if (chrec == chrec_not_analyzed_yet |
| || chrec == chrec_dont_know |
| || chrec_contains_symbols_defined_in_loop (chrec, loop_num)) |
| return false; |
| |
| STRIP_NOPS (chrec); |
| scev = hide_evolution_in_other_loops_than_loop (chrec, loop_num); |
| *res = !tree_contains_chrecs (scev, NULL); |
| return true; |
| } |
| |
| /* Build a polynomial chain of recurrence. */ |
| |
| static inline tree |
| build_polynomial_chrec (unsigned loop_num, |
| tree left, |
| tree right) |
| { |
| bool val; |
| |
| if (left == chrec_dont_know |
| || right == chrec_dont_know) |
| return chrec_dont_know; |
| |
| if (!no_evolution_in_loop_p (left, loop_num, &val) |
| || !val) |
| return chrec_dont_know; |
| |
| /* Types of left and right sides of a chrec should be compatible, but |
| pointer CHRECs are special in that the evolution is of ptroff type. */ |
| if (POINTER_TYPE_P (TREE_TYPE (left))) |
| gcc_checking_assert (ptrofftype_p (TREE_TYPE (right))); |
| else |
| { |
| /* Pointer types should occur only on the left hand side, i.e. in |
| the base of the chrec, and not in the step. */ |
| gcc_checking_assert (!POINTER_TYPE_P (TREE_TYPE (right)) |
| && types_compatible_p (TREE_TYPE (left), |
| TREE_TYPE (right))); |
| } |
| |
| if (chrec_zerop (right)) |
| return left; |
| |
| tree chrec = build2 (POLYNOMIAL_CHREC, TREE_TYPE (left), left, right); |
| CHREC_VARIABLE (chrec) = loop_num; |
| return chrec; |
| } |
| |
| /* Determines whether the expression CHREC is a constant. */ |
| |
| static inline bool |
| evolution_function_is_constant_p (const_tree chrec) |
| { |
| if (chrec == NULL_TREE) |
| return false; |
| |
| return is_gimple_min_invariant (chrec); |
| } |
| |
| /* Determine whether CHREC is an affine evolution function in LOOPNUM. */ |
| |
| static inline bool |
| evolution_function_is_affine_in_loop (const_tree chrec, int loopnum) |
| { |
| if (chrec == NULL_TREE) |
| return false; |
| |
| switch (TREE_CODE (chrec)) |
| { |
| case POLYNOMIAL_CHREC: |
| if (evolution_function_is_invariant_p (CHREC_LEFT (chrec), loopnum) |
| && evolution_function_is_invariant_p (CHREC_RIGHT (chrec), loopnum)) |
| return true; |
| else |
| return false; |
| |
| default: |
| return false; |
| } |
| } |
| |
| /* Determine whether CHREC is an affine evolution function or not. */ |
| |
| static inline bool |
| evolution_function_is_affine_p (const_tree chrec) |
| { |
| return chrec |
| && TREE_CODE (chrec) == POLYNOMIAL_CHREC |
| && evolution_function_is_invariant_p (CHREC_RIGHT (chrec), |
| CHREC_VARIABLE (chrec)) |
| && (TREE_CODE (CHREC_RIGHT (chrec)) != POLYNOMIAL_CHREC |
| || evolution_function_is_affine_p (CHREC_RIGHT (chrec))); |
| } |
| |
| /* Determines whether EXPR does not contains chrec expressions. */ |
| |
| static inline bool |
| tree_does_not_contain_chrecs (const_tree expr) |
| { |
| return !tree_contains_chrecs (expr, NULL); |
| } |
| |
| /* Returns the type of the chrec. */ |
| |
| static inline tree |
| chrec_type (const_tree chrec) |
| { |
| if (automatically_generated_chrec_p (chrec)) |
| return NULL_TREE; |
| |
| return TREE_TYPE (chrec); |
| } |
| |
| static inline tree |
| chrec_fold_op (enum tree_code code, tree type, tree op0, tree op1) |
| { |
| switch (code) |
| { |
| case PLUS_EXPR: |
| return chrec_fold_plus (type, op0, op1); |
| |
| case MINUS_EXPR: |
| return chrec_fold_minus (type, op0, op1); |
| |
| case MULT_EXPR: |
| return chrec_fold_multiply (type, op0, op1); |
| |
| default: |
| gcc_unreachable (); |
| } |
| |
| } |
| |
| #endif /* GCC_TREE_CHREC_H */ |