1 /* A class for building vector tree constants. 2 Copyright (C) 2017-2020 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 under 7 the terms of the GNU General Public License as published by the Free 8 Software Foundation; either version 3, or (at your option) any later 9 version. 10 11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY 12 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 COPYING3. If not see 18 <http://www.gnu.org/licenses/>. */ 19 20 #ifndef GCC_TREE_VECTOR_BUILDER_H 21 #define GCC_TREE_VECTOR_BUILDER_H 22 23 #include "vector-builder.h" 24 25 /* This class is used to build VECTOR_CSTs from a sequence of elements. 26 See vector_builder for more details. */ 27 class tree_vector_builder : public vector_builder<tree, tree, 28 tree_vector_builder> 29 { 30 typedef vector_builder<tree, tree, tree_vector_builder> parent; 31 friend class vector_builder<tree, tree, tree_vector_builder>; 32 33 public: 34 tree_vector_builder () : m_type (0) {} 35 tree_vector_builder (tree, unsigned int, unsigned int); 36 tree build (); 37 38 tree type () const { return m_type; } 39 40 void new_vector (tree, unsigned int, unsigned int); 41 42 private: 43 bool equal_p (const_tree, const_tree) const; 44 bool allow_steps_p () const; 45 bool integral_p (const_tree) const; 46 wide_int step (const_tree, const_tree) const; 47 tree apply_step (tree, unsigned int, const wide_int &) const; 48 bool can_elide_p (const_tree) const; 49 void note_representative (tree *, tree); 50 51 static poly_uint64 shape_nelts (const_tree t) 52 { return TYPE_VECTOR_SUBPARTS (t); } 53 static poly_uint64 nelts_of (const_tree t) 54 { return VECTOR_CST_NELTS (t); } 55 static unsigned int npatterns_of (const_tree t) 56 { return VECTOR_CST_NPATTERNS (t); } 57 static unsigned int nelts_per_pattern_of (const_tree t) 58 { return VECTOR_CST_NELTS_PER_PATTERN (t); } 59 60 tree m_type; 61 }; 62 63 /* Create a new builder for a vector of type TYPE. Initially encode the 64 value as NPATTERNS interleaved patterns with NELTS_PER_PATTERN elements 65 each. */ 66 67 inline 68 tree_vector_builder::tree_vector_builder (tree type, unsigned int npatterns, 69 unsigned int nelts_per_pattern) 70 { 71 new_vector (type, npatterns, nelts_per_pattern); 72 } 73 74 /* Start building a new vector of type TYPE. Initially encode the value 75 as NPATTERNS interleaved patterns with NELTS_PER_PATTERN elements each. */ 76 77 inline void 78 tree_vector_builder::new_vector (tree type, unsigned int npatterns, 79 unsigned int nelts_per_pattern) 80 { 81 m_type = type; 82 parent::new_vector (TYPE_VECTOR_SUBPARTS (type), npatterns, 83 nelts_per_pattern); 84 } 85 86 /* Return true if elements I1 and I2 are equal. */ 87 88 inline bool 89 tree_vector_builder::equal_p (const_tree elt1, const_tree elt2) const 90 { 91 return operand_equal_p (elt1, elt2, OEP_BITWISE); 92 } 93 94 /* Return true if a stepped representation is OK. We don't allow 95 linear series for anything other than integers, to avoid problems 96 with rounding. */ 97 98 inline bool 99 tree_vector_builder::allow_steps_p () const 100 { 101 return INTEGRAL_TYPE_P (TREE_TYPE (m_type)); 102 } 103 104 /* Return true if ELT can be interpreted as an integer. */ 105 106 inline bool 107 tree_vector_builder::integral_p (const_tree elt) const 108 { 109 return TREE_CODE (elt) == INTEGER_CST; 110 } 111 112 /* Return the value of element ELT2 minus the value of element ELT1. 113 Both elements are known to be INTEGER_CSTs. */ 114 115 inline wide_int 116 tree_vector_builder::step (const_tree elt1, const_tree elt2) const 117 { 118 return wi::to_wide (elt2) - wi::to_wide (elt1); 119 } 120 121 /* Return true if we can drop element ELT, even if the retained elements 122 are different. Return false if this would mean losing overflow 123 information. */ 124 125 inline bool 126 tree_vector_builder::can_elide_p (const_tree elt) const 127 { 128 return !CONSTANT_CLASS_P (elt) || !TREE_OVERFLOW (elt); 129 } 130 131 /* Record that ELT2 is being elided, given that ELT1_PTR points to the last 132 encoded element for the containing pattern. */ 133 134 inline void 135 tree_vector_builder::note_representative (tree *elt1_ptr, tree elt2) 136 { 137 if (CONSTANT_CLASS_P (elt2) && TREE_OVERFLOW (elt2)) 138 { 139 gcc_assert (operand_equal_p (*elt1_ptr, elt2, 0)); 140 if (!TREE_OVERFLOW (elt2)) 141 *elt1_ptr = elt2; 142 } 143 } 144 145 #endif 146