1/* Header file for SSA loop optimizations. 2 Copyright (C) 2013-2015 Free Software Foundation, Inc. 3 4This file is part of GCC. 5 6GCC is free software; you can redistribute it and/or modify it under 7the terms of the GNU General Public License as published by the Free 8Software Foundation; either version 3, or (at your option) any later 9version. 10 11GCC is distributed in the hope that it will be useful, but WITHOUT ANY 12WARRANTY; without even the implied warranty of MERCHANTABILITY or 13FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 for 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#ifndef GCC_TREE_SSA_LOOP_H 21#define GCC_TREE_SSA_LOOP_H 22 23#include "wide-int.h" 24 25/* Affine iv. */ 26 27struct affine_iv 28{ 29 /* Iv = BASE + STEP * i. */ 30 tree base, step; 31 32 /* True if this iv does not overflow. */ 33 bool no_overflow; 34}; 35 36/* Description of number of iterations of a loop. All the expressions inside 37 the structure can be evaluated at the end of the loop's preheader 38 (and due to ssa form, also anywhere inside the body of the loop). */ 39 40struct tree_niter_desc 41{ 42 tree assumptions; /* The boolean expression. If this expression evaluates 43 to false, then the other fields in this structure 44 should not be used; there is no guarantee that they 45 will be correct. */ 46 tree may_be_zero; /* The boolean expression. If it evaluates to true, 47 the loop will exit in the first iteration (i.e. 48 its latch will not be executed), even if the niter 49 field says otherwise. */ 50 tree niter; /* The expression giving the number of iterations of 51 a loop (provided that assumptions == true and 52 may_be_zero == false), more precisely the number 53 of executions of the latch of the loop. */ 54 widest_int max; /* The upper bound on the number of iterations of 55 the loop. */ 56 57 /* The simplified shape of the exit condition. The loop exits if 58 CONTROL CMP BOUND is false, where CMP is one of NE_EXPR, 59 LT_EXPR, or GT_EXPR, and step of CONTROL is positive if CMP is 60 LE_EXPR and negative if CMP is GE_EXPR. This information is used 61 by loop unrolling. */ 62 affine_iv control; 63 tree bound; 64 enum tree_code cmp; 65}; 66 67extern bool for_each_index (tree *, bool (*) (tree, tree *, void *), void *); 68extern char *get_lsm_tmp_name (tree ref, unsigned n, const char *suffix = NULL); 69extern unsigned tree_num_loop_insns (struct loop *, struct eni_weights_d *); 70 71/* Returns the loop of the statement STMT. */ 72 73static inline struct loop * 74loop_containing_stmt (gimple stmt) 75{ 76 basic_block bb = gimple_bb (stmt); 77 if (!bb) 78 return NULL; 79 80 return bb->loop_father; 81} 82 83#endif /* GCC_TREE_SSA_LOOP_H */ 84