1/* Copyright (C) 2013-2014 Povilas Kanapickas <povilas@radix.lt>
2
3 Distributed under the Boost Software License, Version 1.0.
4 (See accompanying file LICENSE_1_0.txt or copy at
5 http://www.boost.org/LICENSE_1_0.txt)
6*/
7
8#ifndef LIBSIMDPP_SIMDPP_DETAIL_INSN_F_RCP_RH_H
9#define LIBSIMDPP_SIMDPP_DETAIL_INSN_F_RCP_RH_H
10
11#ifndef LIBSIMDPP_SIMD_H
12 #error "This file must be included through simd.h"
13#endif
14
15#include <simdpp/types.h>
16#include <simdpp/core/f_sub.h>
17#include <simdpp/core/f_mul.h>
18#include <simdpp/core/make_float.h>
19#if SIMDPP_USE_NULL || SIMDPP_USE_NEON || SIMDPP_USE_ALTIVEC
20 #include <cmath>
21 #include <simdpp/detail/null/math.h>
22#endif
23#include <simdpp/detail/vector_array_macros.h>
24
25namespace simdpp {
26namespace SIMDPP_ARCH_NAMESPACE {
27namespace detail {
28namespace insn {
29
30
31static SIMDPP_INL
32float32x4 i_rcp_rh(const float32x4& cx, const float32x4& a)
33{
34 float32<4> x = cx;
35#if SIMDPP_USE_NULL || SIMDPP_USE_NEON_NO_FLT_SP
36 float32x4 r;
37 for (unsigned i = 0; i < a.length; i++) {
38 float ix = x.el(i);
39 float ia = a.el(i);
40 r.el(i) = ix*(2.0f - ix*ia);
41 }
42 return r;
43#elif SIMDPP_USE_SSE2 || SIMDPP_USE_MSA
44 float32x4 r;
45
46 r = mul(a, x);
47 r = sub(2.0, r);
48 x = mul(x, r);
49
50 return x;
51#elif SIMDPP_USE_NEON_FLT_SP
52 float32x4 r;
53 r = vrecpsq_f32(a.native(), x.native());
54 x = mul(x, r);
55
56 return x;
57#elif SIMDPP_USE_ALTIVEC
58 float32x4 r, c2;
59 c2 = make_float(2.0f);
60 // -(x*a-c2)
61 r = vec_nmsub(x.native(), a.native(), c2.native());
62 x = mul(x, r);
63 return x;
64#endif
65}
66
67#if SIMDPP_USE_AVX
68static SIMDPP_INL
69float32x8 i_rcp_rh(const float32x8& cx, const float32x8& a)
70{
71 float32x8 r, x = cx;
72
73 r = mul(a, x);
74 r = sub(2.0, r);
75 x = mul(x, r);
76
77 return x;
78}
79#endif
80
81#if SIMDPP_USE_AVX512F
82static SIMDPP_INL
83float32<16> i_rcp_rh(const float32<16>& cx, const float32<16>& a)
84{
85 float32<16> r, x = cx;
86
87 r = mul(a, x);
88 r = sub(2.0, r);
89 x = mul(x, r);
90
91 return x;
92}
93#endif
94
95template<unsigned N> SIMDPP_INL
96float32<N> i_rcp_rh(const float32<N>& x, const float32<N>& a)
97{
98 SIMDPP_VEC_ARRAY_IMPL2(float32<N>, i_rcp_rh, x, a);
99}
100
101
102} // namespace insn
103} // namespace detail
104} // namespace SIMDPP_ARCH_NAMESPACE
105} // namespace simdpp
106
107#endif
108
109