1 /****************************************************************************
2 **
3 ** Copyright (C) 2017 The Qt Company Ltd.
4 ** Contact: https://www.qt.io/licensing/
5 **
6 ** This file is part of the QtCore module of the Qt Toolkit.
7 **
8 ** $QT_BEGIN_LICENSE:LGPL$
9 ** Commercial License Usage
10 ** Licensees holding valid commercial Qt licenses may use this file in
11 ** accordance with the commercial license agreement provided with the
12 ** Software or, alternatively, in accordance with the terms contained in
13 ** a written agreement between you and The Qt Company. For licensing terms
14 ** and conditions see https://www.qt.io/terms-conditions. For further
15 ** information use the contact form at https://www.qt.io/contact-us.
16 **
17 ** GNU Lesser General Public License Usage
18 ** Alternatively, this file may be used under the terms of the GNU Lesser
19 ** General Public License version 3 as published by the Free Software
20 ** Foundation and appearing in the file LICENSE.LGPL3 included in the
21 ** packaging of this file. Please review the following information to
22 ** ensure the GNU Lesser General Public License version 3 requirements
23 ** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
24 **
25 ** GNU General Public License Usage
26 ** Alternatively, this file may be used under the terms of the GNU
27 ** General Public License version 2.0 or (at your option) the GNU General
28 ** Public license version 3 or any later version approved by the KDE Free
29 ** Qt Foundation. The licenses are as published by the Free Software
30 ** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
31 ** included in the packaging of this file. Please review the following
32 ** information to ensure the GNU General Public License requirements will
33 ** be met: https://www.gnu.org/licenses/gpl-2.0.html and
34 ** https://www.gnu.org/licenses/gpl-3.0.html.
35 **
36 ** $QT_END_LICENSE$
37 **
38 ****************************************************************************/
39
40 #include "private/qsimd_p.h"
41
42 // The x86 F16C instructions operate on AVX registers, so AVX support is
43 // required. We don't need to check for __F16C__ because we this file wouldn't
44 // have been compiled if the support was missing in the first place, and not
45 // all compilers define it. Technically, we didn't need to check for __AVX__
46 // either.
47 #if !QT_COMPILER_SUPPORTS_HERE(AVX)
48 # error "AVX support required"
49 #endif
50
51 #ifdef __cplusplus
52 QT_BEGIN_NAMESPACE
53 extern "C" {
54 #endif
55
QT_FUNCTION_TARGET(F16C)56 QT_FUNCTION_TARGET(F16C)
57 void qFloatToFloat16_fast(quint16 *out, const float *in, qsizetype len) Q_DECL_NOEXCEPT
58 {
59 qsizetype i = 0;
60 int epilog_i;
61 for (; i < len - 7; i += 8)
62 _mm_storeu_si128((__m128i *)(out + i), _mm256_cvtps_ph(_mm256_loadu_ps(in + i), 0));
63 if (i < len - 3) {
64 _mm_storel_epi64((__m128i *)(out + i), _mm_cvtps_ph(_mm_loadu_ps(in + i), 0));
65 i += 4;
66 }
67 // Inlining "qfloat16::qfloat16(float f)":
68 for (epilog_i = 0; i < len && epilog_i < 3; ++i, ++epilog_i)
69 out[i] = _mm_extract_epi16(_mm_cvtps_ph(_mm_set_ss(in[i]), 0), 0);
70 }
71
QT_FUNCTION_TARGET(F16C)72 QT_FUNCTION_TARGET(F16C)
73 void qFloatFromFloat16_fast(float *out, const quint16 *in, qsizetype len) Q_DECL_NOEXCEPT
74 {
75 qsizetype i = 0;
76 int epilog_i;
77 for (; i < len - 7; i += 8)
78 _mm256_storeu_ps(out + i, _mm256_cvtph_ps(_mm_loadu_si128((const __m128i *)(in + i))));
79 if (i < len - 3) {
80 _mm_storeu_ps(out + i, _mm_cvtph_ps(_mm_loadl_epi64((const __m128i *)(in + i))));
81 i += 4;
82 }
83 // Inlining "qfloat16::operator float()":
84 for (epilog_i = 0; i < len && epilog_i < 3; ++i, ++epilog_i)
85 out[i] = _mm_cvtss_f32(_mm_cvtph_ps(_mm_cvtsi32_si128(in[i])));
86 }
87
88 #ifdef __cplusplus
89 } // extern "C"
90 QT_END_NAMESPACE
91 #endif
92