1 //=================================================================================================
2 /*!
3 // \file blaze/math/simd/Reduce.h
4 // \brief Header file for the generic SIMD reduction functionality
5 //
6 // Copyright (C) 2012-2020 Klaus Iglberger - All Rights Reserved
7 //
8 // This file is part of the Blaze library. You can redistribute it and/or modify it under
9 // the terms of the New (Revised) BSD License. Redistribution and use in source and binary
10 // forms, with or without modification, are permitted provided that the following conditions
11 // are met:
12 //
13 // 1. Redistributions of source code must retain the above copyright notice, this list of
14 // conditions and the following disclaimer.
15 // 2. Redistributions in binary form must reproduce the above copyright notice, this list
16 // of conditions and the following disclaimer in the documentation and/or other materials
17 // provided with the distribution.
18 // 3. Neither the names of the Blaze development group nor the names of its contributors
19 // may be used to endorse or promote products derived from this software without specific
20 // prior written permission.
21 //
22 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
23 // EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24 // OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
25 // SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26 // INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
27 // TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
28 // BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29 // CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
30 // ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
31 // DAMAGE.
32 */
33 //=================================================================================================
34
35 #ifndef _BLAZE_MATH_SIMD_REDUCE_H_
36 #define _BLAZE_MATH_SIMD_REDUCE_H_
37
38
39 //*************************************************************************************************
40 // Includes
41 //*************************************************************************************************
42
43 #include <blaze/math/functors/Forward.h>
44 #include <blaze/math/simd/Prod.h>
45 #include <blaze/math/simd/SIMDPack.h>
46 #include <blaze/math/simd/Sum.h>
47 #include <blaze/math/simd/Storea.h>
48 #include <blaze/util/typetraits/AlignmentOf.h>
49
50
51 namespace blaze {
52
53 //=================================================================================================
54 //
55 // SIMD REDUCTION
56 //
57 //=================================================================================================
58
59 //*************************************************************************************************
60 /*!\brief Reduces the elements in the given SIMD vector.
61 // \ingroup simd
62 //
63 // \param a The SIMD vector to be reduced.
64 // \param op The reduction operation.
65 // \return The result of the reduction operation.
66 */
67 template< typename T, typename OP >
decltype(auto)68 inline decltype(auto) reduce( const SIMDPack<T>& a, OP op )
69 {
70 using ValueType = typename T::ValueType;
71
72 alignas( AlignmentOf_v<ValueType> ) ValueType array[T::size];
73 storea( array, *a );
74
75 ValueType redux( array[0UL] );
76 for( size_t k=1UL; k<T::size; ++k ) {
77 redux = op( redux, array[k] );
78 }
79
80 return redux;
81 }
82 //*************************************************************************************************
83
84
85 //*************************************************************************************************
86 /*! \cond BLAZE_INTERNAL */
87 /*!\brief Reduces the elements in the given SIMD vector by means of addition.
88 // \ingroup simd
89 //
90 // \param a The vector to be summed up.
91 // \return The sum of all vector elements.
92 */
93 template< typename T >
decltype(auto)94 inline decltype(auto) reduce( const SIMDPack<T>& a, const Add& /*op*/ )
95 {
96 return sum( *a );
97 }
98 /*! \endcond */
99 //*************************************************************************************************
100
101
102 //*************************************************************************************************
103 /*! \cond BLAZE_INTERNAL */
104 /*!\brief Reduces the elements in the given SIMD vector by means of multiplication.
105 // \ingroup simd
106 //
107 // \param a The vector to be reduced by multiplication.
108 // \return The produdct of all vector elements.
109 */
110 template< typename T >
decltype(auto)111 inline decltype(auto) reduce( const SIMDPack<T>& a, const Mult& /*op*/ )
112 {
113 return prod( *a );
114 }
115 /*! \endcond */
116 //*************************************************************************************************
117
118 } // namespace blaze
119
120 #endif
121