Branch data Line data Source code
1 : : /* A representation of vector permutation indices.
2 : : Copyright (C) 2017-2025 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_VEC_PERN_INDICES_H
21 : : #define GCC_VEC_PERN_INDICES_H 1
22 : :
23 : : #include "int-vector-builder.h"
24 : :
25 : : /* A vector_builder for building constant permutation vectors.
26 : : The elements do not need to be clamped to a particular range
27 : : of input elements. */
28 : : typedef int_vector_builder<poly_int64> vec_perm_builder;
29 : :
30 : : /* This class represents a constant permutation vector, such as that used
31 : : as the final operand to a VEC_PERM_EXPR.
32 : :
33 : : Permutation vectors select indices modulo the number of input elements,
34 : : and the class canonicalizes each permutation vector for a particular
35 : : number of input vectors and for a particular number of elements per
36 : : input. For example, the gimple statements:
37 : :
38 : : _1 = VEC_PERM_EXPR <a, a, { 0, 2, 4, 6, 0, 2, 4, 6 }>;
39 : : _2 = VEC_PERM_EXPR <a, a, { 0, 2, 4, 6, 8, 10, 12, 14 }>;
40 : : _3 = VEC_PERM_EXPR <a, a, { 0, 2, 20, 22, 24, 2, 4, 14 }>;
41 : :
42 : : effectively have only a single vector input "a". If "a" has 8
43 : : elements, the indices select elements modulo 8, which makes all three
44 : : VEC_PERM_EXPRs equivalent. The canonical form is for the indices to be
45 : : in the range [0, number of input elements - 1], so the class treats the
46 : : second and third permutation vectors as though they had been the first.
47 : :
48 : : The class copes with cases in which the input and output vectors have
49 : : different numbers of elements. */
50 : 3846568 : class vec_perm_indices
51 : : {
52 : : typedef poly_int64 element_type;
53 : :
54 : : public:
55 : : vec_perm_indices ();
56 : : vec_perm_indices (const vec_perm_builder &, unsigned int, poly_uint64);
57 : :
58 : : void new_vector (const vec_perm_builder &, unsigned int, poly_uint64);
59 : : void new_expanded_vector (const vec_perm_indices &, unsigned int);
60 : : bool new_shrunk_vector (const vec_perm_indices &, unsigned int);
61 : : void rotate_inputs (int delta);
62 : :
63 : : /* Return the underlying vector encoding. */
64 : : const vec_perm_builder &encoding () const { return m_encoding; }
65 : :
66 : : /* Return the number of output elements. This is called length ()
67 : : so that we present a more vec-like interface. */
68 : 2027250 : poly_uint64 length () const { return m_encoding.full_nelts (); }
69 : :
70 : : /* Return the number of input vectors being permuted. */
71 : 17862 : unsigned int ninputs () const { return m_ninputs; }
72 : :
73 : : /* Return the number of elements in each input vector. */
74 : 1105177 : poly_uint64 nelts_per_input () const { return m_nelts_per_input; }
75 : :
76 : : /* Return the total number of input elements. */
77 : 5285412 : poly_uint64 input_nelts () const { return m_ninputs * m_nelts_per_input; }
78 : :
79 : : element_type clamp (element_type) const;
80 : : element_type operator[] (unsigned int i) const;
81 : : bool series_p (unsigned int, unsigned int, element_type, element_type) const;
82 : : bool all_in_range_p (element_type, element_type) const;
83 : : bool all_from_input_p (unsigned int) const;
84 : :
85 : : private:
86 : : vec_perm_indices (const vec_perm_indices &);
87 : :
88 : : vec_perm_builder m_encoding;
89 : : unsigned int m_ninputs;
90 : : poly_uint64 m_nelts_per_input;
91 : : };
92 : :
93 : : bool tree_to_vec_perm_builder (vec_perm_builder *, tree);
94 : : tree vec_perm_indices_to_tree (tree, const vec_perm_indices &);
95 : : rtx vec_perm_indices_to_rtx (machine_mode, const vec_perm_indices &);
96 : :
97 : : inline
98 : 1073550 : vec_perm_indices::vec_perm_indices ()
99 : 1073550 : : m_ninputs (0),
100 : 1073550 : m_nelts_per_input (0)
101 : : {
102 : : }
103 : :
104 : : /* Construct a permutation vector that selects between NINPUTS vector
105 : : inputs that have NELTS_PER_INPUT elements each. Take the elements of
106 : : the new vector from ELEMENTS, clamping each one to be in range. */
107 : :
108 : : inline
109 : 2918305 : vec_perm_indices::vec_perm_indices (const vec_perm_builder &elements,
110 : : unsigned int ninputs,
111 : 2918305 : poly_uint64 nelts_per_input)
112 : : {
113 : 2918305 : new_vector (elements, ninputs, nelts_per_input);
114 : 2918305 : }
115 : :
116 : : /* Return the canonical value for permutation vector element ELT,
117 : : taking into account the current number of input elements. */
118 : :
119 : : inline vec_perm_indices::element_type
120 : 47279780 : vec_perm_indices::clamp (element_type elt) const
121 : : {
122 : 40348449 : element_type limit = input_nelts (), elem_within_input;
123 : 47279780 : HOST_WIDE_INT input;
124 : 47279780 : if (!can_div_trunc_p (elt, limit, &input, &elem_within_input))
125 : : return elt;
126 : :
127 : : /* Treat negative elements as counting from the end. This only matters
128 : : if the vector size is not a power of 2. */
129 : 47279780 : if (known_lt (elem_within_input, 0))
130 : 339008 : return elem_within_input + limit;
131 : :
132 : : return elem_within_input;
133 : : }
134 : :
135 : : /* Return the value of vector element I, which might or might not be
136 : : explicitly encoded. */
137 : :
138 : : inline vec_perm_indices::element_type
139 : 11835997 : vec_perm_indices::operator[] (unsigned int i) const
140 : : {
141 : 11835997 : return clamp (m_encoding.elt (i));
142 : : }
143 : :
144 : : /* Return true if the permutation vector only selects elements from
145 : : input I. */
146 : :
147 : : inline bool
148 : 2064945 : vec_perm_indices::all_from_input_p (unsigned int i) const
149 : : {
150 : 2064945 : return all_in_range_p (i * m_nelts_per_input, m_nelts_per_input);
151 : : }
152 : :
153 : : #endif
|
