1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
|
// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "media/base/vector_math.h"
#include "media/base/vector_math_testing.h"
#include "base/cpu.h"
#include "base/logging.h"
#include "build/build_config.h"
#if defined(ARCH_CPU_X86_FAMILY) && defined(__SSE__)
#include <xmmintrin.h>
#endif
namespace media {
namespace vector_math {
void FMAC(const float src[], float scale, int len, float dest[]) {
// Ensure |src| and |dest| are 16-byte aligned.
DCHECK_EQ(0u, reinterpret_cast<uintptr_t>(src) & (kRequiredAlignment - 1));
DCHECK_EQ(0u, reinterpret_cast<uintptr_t>(dest) & (kRequiredAlignment - 1));
// Rely on function level static initialization to keep VectorFMACProc
// selection thread safe.
typedef void (*VectorFMACProc)(const float src[], float scale, int len,
float dest[]);
#if defined(ARCH_CPU_X86_FAMILY) && defined(__SSE__)
static const VectorFMACProc kVectorFMACProc =
base::CPU().has_sse() ? FMAC_SSE : FMAC_C;
#else
static const VectorFMACProc kVectorFMACProc = FMAC_C;
#endif
return kVectorFMACProc(src, scale, len, dest);
}
void FMAC_C(const float src[], float scale, int len, float dest[]) {
for (int i = 0; i < len; ++i)
dest[i] += src[i] * scale;
}
#if defined(ARCH_CPU_X86_FAMILY) && defined(__SSE__)
void FMAC_SSE(const float src[], float scale, int len, float dest[]) {
__m128 m_scale = _mm_set_ps1(scale);
int rem = len % 4;
for (int i = 0; i < len - rem; i += 4) {
_mm_store_ps(dest + i, _mm_add_ps(_mm_load_ps(dest + i),
_mm_mul_ps(_mm_load_ps(src + i), m_scale)));
}
// Handle any remaining values that wouldn't fit in an SSE pass.
if (rem)
FMAC_C(src + len - rem, scale, rem, dest + len - rem);
}
#endif
} // namespace vector_math
} // namespace media
|
