opencv/3rdparty/openexr/IlmImf/ImfDwaCompressorSimd.h

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///////////////////////////////////////////////////////////////////////////
//
// Copyright (c) 2009-2014 DreamWorks Animation LLC.
//
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of DreamWorks Animation nor the names of
// its contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
///////////////////////////////////////////////////////////////////////////
#ifndef IMF_DWACOMPRESSORSIMD_H_HAS_BEEN_INCLUDED
#define IMF_DWACOMPRESSORSIMD_H_HAS_BEEN_INCLUDED
//
// Various SSE accelerated functions, used by Imf::DwaCompressor.
// These have been separated into a separate .h file, as the fast
// paths are done with template specialization.
//
// Unless otherwise noted, all pointers are assumed to be 32-byte
// aligned. Unaligned pointers may risk seg-faulting.
//
#include "ImfNamespace.h"
#include "ImfSimd.h"
#include "ImfSystemSpecific.h"
#include "OpenEXRConfig.h"
#include <half.h>
#include <assert.h>
#include <algorithm>
OPENEXR_IMF_INTERNAL_NAMESPACE_HEADER_ENTER
#define _SSE_ALIGNMENT 32
#define _SSE_ALIGNMENT_MASK 0x0F
#define _AVX_ALIGNMENT_MASK 0x1F
//
// Test if we should enable GCC inline asm paths for AVX
//
#ifdef OPENEXR_IMF_HAVE_GCC_INLINE_ASM_AVX
#define IMF_HAVE_GCC_INLINEASM
#ifdef __LP64__
#define IMF_HAVE_GCC_INLINEASM_64
#endif /* __LP64__ */
#endif /* OPENEXR_IMF_HAVE_GCC_INLINE_ASM_AVX */
//
// A simple 64-element array, aligned properly for SIMD access.
//
template <class T>
class SimdAlignedBuffer64
{
public:
SimdAlignedBuffer64(): _buffer (0), _handle (0)
{
alloc();
}
SimdAlignedBuffer64(const SimdAlignedBuffer64 &rhs): _handle(0)
{
alloc();
memcpy (_buffer, rhs._buffer, 64 * sizeof (T));
}
SimdAlignedBuffer64 &operator=(const SimdAlignedBuffer64 &rhs)
{
memcpy (_buffer, rhs._buffer, 64 * sizeof (T));
return *this;
}
#if __cplusplus >= 201103L
SimdAlignedBuffer64(SimdAlignedBuffer64 &&rhs) noexcept
: _handle(rhs._handle), _buffer(rhs._buffer)
{
rhs._handle = nullptr;
rhs._buffer = nullptr;
}
SimdAlignedBuffer64 &operator=(SimdAlignedBuffer64 &&rhs) noexcept
{
std::swap(_handle, rhs._handle);
std::swap(_buffer, rhs._buffer);
return *this;
}
#endif
~SimdAlignedBuffer64 ()
{
if (_handle)
EXRFreeAligned (_handle);
_handle = 0;
_buffer = 0;
}
void alloc()
{
//
// Try EXRAllocAligned first - but it might fallback to
// unaligned allocs. If so, overalloc.
//
_handle = (char *) EXRAllocAligned
(64 * sizeof(T), _SSE_ALIGNMENT);
if (((size_t)_handle & (_SSE_ALIGNMENT - 1)) == 0)
{
_buffer = (T *)_handle;
return;
}
EXRFreeAligned(_handle);
_handle = (char *) EXRAllocAligned
(64 * sizeof(T) + _SSE_ALIGNMENT, _SSE_ALIGNMENT);
char *aligned = _handle;
while ((size_t)aligned & (_SSE_ALIGNMENT - 1))
aligned++;
_buffer = (T *)aligned;
}
T *_buffer;
private:
char *_handle;
};
typedef SimdAlignedBuffer64<float> SimdAlignedBuffer64f;
typedef SimdAlignedBuffer64<unsigned short> SimdAlignedBuffer64us;
namespace {
//
// Color space conversion, Inverse 709 CSC, Y'CbCr -> R'G'B'
//
void
csc709Inverse (float &comp0, float &comp1, float &comp2)
{
float src[3];
src[0] = comp0;
src[1] = comp1;
src[2] = comp2;
comp0 = src[0] + 1.5747f * src[2];
comp1 = src[0] - 0.1873f * src[1] - 0.4682f * src[2];
comp2 = src[0] + 1.8556f * src[1];
}
#ifndef IMF_HAVE_SSE2
//
// Scalar color space conversion, based on 709 primiary chromaticies.
// No scaling or offsets, just the matrix
//
void
csc709Inverse64 (float *comp0, float *comp1, float *comp2)
{
for (int i = 0; i < 64; ++i)
csc709Inverse (comp0[i], comp1[i], comp2[i]);
}
#else /* IMF_HAVE_SSE2 */
//
// SSE2 color space conversion
//
void
csc709Inverse64 (float *comp0, float *comp1, float *comp2)
{
__m128 c0 = { 1.5747f, 1.5747f, 1.5747f, 1.5747f};
__m128 c1 = { 1.8556f, 1.8556f, 1.8556f, 1.8556f};
__m128 c2 = {-0.1873f, -0.1873f, -0.1873f, -0.1873f};
__m128 c3 = {-0.4682f, -0.4682f, -0.4682f, -0.4682f};
__m128 *r = (__m128 *)comp0;
__m128 *g = (__m128 *)comp1;
__m128 *b = (__m128 *)comp2;
__m128 src[3];
#define CSC_INVERSE_709_SSE2_LOOP(i) \
src[0] = r[i]; \
src[1] = g[i]; \
src[2] = b[i]; \
\
r[i] = _mm_add_ps (r[i], _mm_mul_ps (src[2], c0)); \
\
g[i] = _mm_mul_ps (g[i], c2); \
src[2] = _mm_mul_ps (src[2], c3); \
g[i] = _mm_add_ps (g[i], src[0]); \
g[i] = _mm_add_ps (g[i], src[2]); \
\
b[i] = _mm_mul_ps (c1, src[1]); \
b[i] = _mm_add_ps (b[i], src[0]);
CSC_INVERSE_709_SSE2_LOOP (0)
CSC_INVERSE_709_SSE2_LOOP (1)
CSC_INVERSE_709_SSE2_LOOP (2)
CSC_INVERSE_709_SSE2_LOOP (3)
CSC_INVERSE_709_SSE2_LOOP (4)
CSC_INVERSE_709_SSE2_LOOP (5)
CSC_INVERSE_709_SSE2_LOOP (6)
CSC_INVERSE_709_SSE2_LOOP (7)
CSC_INVERSE_709_SSE2_LOOP (8)
CSC_INVERSE_709_SSE2_LOOP (9)
CSC_INVERSE_709_SSE2_LOOP (10)
CSC_INVERSE_709_SSE2_LOOP (11)
CSC_INVERSE_709_SSE2_LOOP (12)
CSC_INVERSE_709_SSE2_LOOP (13)
CSC_INVERSE_709_SSE2_LOOP (14)
CSC_INVERSE_709_SSE2_LOOP (15)
}
#endif /* IMF_HAVE_SSE2 */
//
// Color space conversion, Forward 709 CSC, R'G'B' -> Y'CbCr
//
// Simple FPU color space conversion. Based on the 709
// primary chromaticies, with no scaling or offsets.
//
void
csc709Forward64 (float *comp0, float *comp1, float *comp2)
{
float src[3];
for (int i = 0; i<64; ++i)
{
src[0] = comp0[i];
src[1] = comp1[i];
src[2] = comp2[i];
comp0[i] = 0.2126f * src[0] + 0.7152f * src[1] + 0.0722f * src[2];
comp1[i] = -0.1146f * src[0] - 0.3854f * src[1] + 0.5000f * src[2];
comp2[i] = 0.5000f * src[0] - 0.4542f * src[1] - 0.0458f * src[2];
}
}
//
// Byte interleaving of 2 byte arrays:
// src0 = AAAA
// src1 = BBBB
// dst = ABABABAB
//
// numBytes is the size of each of the source buffers
//
#ifndef IMF_HAVE_SSE2
//
// Scalar default implementation
//
void
interleaveByte2 (char *dst, char *src0, char *src1, int numBytes)
{
for (int x = 0; x < numBytes; ++x)
{
dst[2 * x] = src0[x];
dst[2 * x + 1] = src1[x];
}
}
#else /* IMF_HAVE_SSE2 */
//
// SSE2 byte interleaving
//
void
interleaveByte2 (char *dst, char *src0, char *src1, int numBytes)
{
int dstAlignment = (size_t)dst % 16;
int src0Alignment = (size_t)src0 % 16;
int src1Alignment = (size_t)src1 % 16;
__m128i *dst_epi8 = (__m128i*)dst;
__m128i *src0_epi8 = (__m128i*)src0;
__m128i *src1_epi8 = (__m128i*)src1;
int sseWidth = numBytes / 16;
if ((!dstAlignment) && (!src0Alignment) && (!src1Alignment))
{
__m128i tmp0, tmp1;
//
// Aligned loads and stores
//
for (int x = 0; x < sseWidth; ++x)
{
tmp0 = src0_epi8[x];
tmp1 = src1_epi8[x];
_mm_stream_si128 (&dst_epi8[2 * x],
_mm_unpacklo_epi8 (tmp0, tmp1));
_mm_stream_si128 (&dst_epi8[2 * x + 1],
_mm_unpackhi_epi8 (tmp0, tmp1));
}
//
// Then do run the leftovers one at a time
//
for (int x = 16 * sseWidth; x < numBytes; ++x)
{
dst[2 * x] = src0[x];
dst[2 * x + 1] = src1[x];
}
}
else if ((!dstAlignment) && (src0Alignment == 8) && (src1Alignment == 8))
{
//
// Aligned stores, but catch up a few values so we can
// use aligned loads
//
for (int x = 0; x < std::min (numBytes, 8); ++x)
{
dst[2 * x] = src0[x];
dst[2 * x + 1] = src1[x];
}
if (numBytes > 8)
{
dst_epi8 = (__m128i*)&dst[16];
src0_epi8 = (__m128i*)&src0[8];
src1_epi8 = (__m128i*)&src1[8];
sseWidth = (numBytes - 8) / 16;
for (int x=0; x<sseWidth; ++x)
{
_mm_stream_si128 (&dst_epi8[2 * x],
_mm_unpacklo_epi8 (src0_epi8[x], src1_epi8[x]));
_mm_stream_si128 (&dst_epi8[2 * x + 1],
_mm_unpackhi_epi8 (src0_epi8[x], src1_epi8[x]));
}
//
// Then do run the leftovers one at a time
//
for (int x = 16 * sseWidth + 8; x < numBytes; ++x)
{
dst[2 * x] = src0[x];
dst[2 * x + 1] = src1[x];
}
}
}
else
{
//
// Unaligned everything
//
for (int x = 0; x < sseWidth; ++x)
{
__m128i tmpSrc0_epi8 = _mm_loadu_si128 (&src0_epi8[x]);
__m128i tmpSrc1_epi8 = _mm_loadu_si128 (&src1_epi8[x]);
_mm_storeu_si128 (&dst_epi8[2 * x],
_mm_unpacklo_epi8 (tmpSrc0_epi8, tmpSrc1_epi8));
_mm_storeu_si128 (&dst_epi8[2 * x + 1],
_mm_unpackhi_epi8 (tmpSrc0_epi8, tmpSrc1_epi8));
}
//
// Then do run the leftovers one at a time
//
for (int x = 16 * sseWidth; x < numBytes; ++x)
{
dst[2 * x] = src0[x];
dst[2 * x + 1] = src1[x];
}
}
}
#endif /* IMF_HAVE_SSE2 */
//
// Float -> half float conversion
//
// To enable F16C based conversion, we can't rely on compile-time
// detection, hence the multiple defined versions. Pick one based
// on runtime cpuid detection.
//
//
// Default boring conversion
//
void
convertFloatToHalf64_scalar (unsigned short *dst, float *src)
{
for (int i=0; i<64; ++i)
dst[i] = ((half)src[i]).bits();
}
//
// F16C conversion - Assumes aligned src and dst
//
void
convertFloatToHalf64_f16c (unsigned short *dst, float *src)
{
//
// Ordinarly, I'd avoid using inline asm and prefer intrinsics.
// However, in order to get the intrinsics, we need to tell
// the compiler to generate VEX instructions.
//
// (On the GCC side, -mf16c goes ahead and activates -mavc,
// resulting in VEX code. Without -mf16c, no intrinsics..)
//
// Now, it's quite likely that we'll find ourselves in situations
// where we want to build *without* VEX, in order to maintain
// maximum compatability. But to get there with intrinsics,
// we'd need to break out code into a separate file. Bleh.
// I'll take the asm.
//
#if defined IMF_HAVE_GCC_INLINEASM
__asm__
("vmovaps (%0), %%ymm0 \n"
"vmovaps 0x20(%0), %%ymm1 \n"
"vmovaps 0x40(%0), %%ymm2 \n"
"vmovaps 0x60(%0), %%ymm3 \n"
"vcvtps2ph $0, %%ymm0, %%xmm0 \n"
"vcvtps2ph $0, %%ymm1, %%xmm1 \n"
"vcvtps2ph $0, %%ymm2, %%xmm2 \n"
"vcvtps2ph $0, %%ymm3, %%xmm3 \n"
"vmovdqa %%xmm0, 0x00(%1) \n"
"vmovdqa %%xmm1, 0x10(%1) \n"
"vmovdqa %%xmm2, 0x20(%1) \n"
"vmovdqa %%xmm3, 0x30(%1) \n"
"vmovaps 0x80(%0), %%ymm0 \n"
"vmovaps 0xa0(%0), %%ymm1 \n"
"vmovaps 0xc0(%0), %%ymm2 \n"
"vmovaps 0xe0(%0), %%ymm3 \n"
"vcvtps2ph $0, %%ymm0, %%xmm0 \n"
"vcvtps2ph $0, %%ymm1, %%xmm1 \n"
"vcvtps2ph $0, %%ymm2, %%xmm2 \n"
"vcvtps2ph $0, %%ymm3, %%xmm3 \n"
"vmovdqa %%xmm0, 0x40(%1) \n"
"vmovdqa %%xmm1, 0x50(%1) \n"
"vmovdqa %%xmm2, 0x60(%1) \n"
"vmovdqa %%xmm3, 0x70(%1) \n"
#ifndef __AVX__
"vzeroupper \n"
#endif /* __AVX__ */
: /* Output */
: /* Input */ "r"(src), "r"(dst)
#ifndef __AVX__
: /* Clobber */ "%xmm0", "%xmm1", "%xmm2", "%xmm3", "memory"
#else
: /* Clobber */ "%ymm0", "%ymm1", "%ymm2", "%ymm3", "memory"
#endif /* __AVX__ */
);
#else
convertFloatToHalf64_scalar (dst, src);
#endif /* IMF_HAVE_GCC_INLINEASM */
}
//
// Convert an 8x8 block of HALF from zig-zag order to
// FLOAT in normal order. The order we want is:
//
// src dst
// 0 1 2 3 4 5 6 7 0 1 5 6 14 15 27 28
// 8 9 10 11 12 13 14 15 2 4 7 13 16 26 29 42
// 16 17 18 19 20 21 22 23 3 8 12 17 25 30 41 43
// 24 25 26 27 28 29 30 31 9 11 18 24 31 40 44 53
// 32 33 34 35 36 37 38 39 10 19 23 32 39 45 52 54
// 40 41 42 43 44 45 46 47 20 22 33 38 46 51 55 60
// 48 49 50 51 52 53 54 55 21 34 37 47 50 56 59 61
// 56 57 58 59 60 61 62 63 35 36 48 49 57 58 62 63
//
void
fromHalfZigZag_scalar (unsigned short *src, float *dst)
{
half *srcHalf = (half *)src;
dst[0] = (float)srcHalf[0];
dst[1] = (float)srcHalf[1];
dst[2] = (float)srcHalf[5];
dst[3] = (float)srcHalf[6];
dst[4] = (float)srcHalf[14];
dst[5] = (float)srcHalf[15];
dst[6] = (float)srcHalf[27];
dst[7] = (float)srcHalf[28];
dst[8] = (float)srcHalf[2];
dst[9] = (float)srcHalf[4];
dst[10] = (float)srcHalf[7];
dst[11] = (float)srcHalf[13];
dst[12] = (float)srcHalf[16];
dst[13] = (float)srcHalf[26];
dst[14] = (float)srcHalf[29];
dst[15] = (float)srcHalf[42];
dst[16] = (float)srcHalf[3];
dst[17] = (float)srcHalf[8];
dst[18] = (float)srcHalf[12];
dst[19] = (float)srcHalf[17];
dst[20] = (float)srcHalf[25];
dst[21] = (float)srcHalf[30];
dst[22] = (float)srcHalf[41];
dst[23] = (float)srcHalf[43];
dst[24] = (float)srcHalf[9];
dst[25] = (float)srcHalf[11];
dst[26] = (float)srcHalf[18];
dst[27] = (float)srcHalf[24];
dst[28] = (float)srcHalf[31];
dst[29] = (float)srcHalf[40];
dst[30] = (float)srcHalf[44];
dst[31] = (float)srcHalf[53];
dst[32] = (float)srcHalf[10];
dst[33] = (float)srcHalf[19];
dst[34] = (float)srcHalf[23];
dst[35] = (float)srcHalf[32];
dst[36] = (float)srcHalf[39];
dst[37] = (float)srcHalf[45];
dst[38] = (float)srcHalf[52];
dst[39] = (float)srcHalf[54];
dst[40] = (float)srcHalf[20];
dst[41] = (float)srcHalf[22];
dst[42] = (float)srcHalf[33];
dst[43] = (float)srcHalf[38];
dst[44] = (float)srcHalf[46];
dst[45] = (float)srcHalf[51];
dst[46] = (float)srcHalf[55];
dst[47] = (float)srcHalf[60];
dst[48] = (float)srcHalf[21];
dst[49] = (float)srcHalf[34];
dst[50] = (float)srcHalf[37];
dst[51] = (float)srcHalf[47];
dst[52] = (float)srcHalf[50];
dst[53] = (float)srcHalf[56];
dst[54] = (float)srcHalf[59];
dst[55] = (float)srcHalf[61];
dst[56] = (float)srcHalf[35];
dst[57] = (float)srcHalf[36];
dst[58] = (float)srcHalf[48];
dst[59] = (float)srcHalf[49];
dst[60] = (float)srcHalf[57];
dst[61] = (float)srcHalf[58];
dst[62] = (float)srcHalf[62];
dst[63] = (float)srcHalf[63];
}
//
// If we can form the correct ordering in xmm registers,
// we can use F16C to convert from HALF -> FLOAT. However,
// making the correct order isn't trivial.
//
// We want to re-order a source 8x8 matrix from:
//
// 0 1 2 3 4 5 6 7 0 1 5 6 14 15 27 28
// 8 9 10 11 12 13 14 15 2 4 7 13 16 26 29 42
// 16 17 18 19 20 21 22 23 3 8 12 17 25 30 41 43
// 24 25 26 27 28 29 30 31 9 11 18 24 31 40 44 53 (A)
// 32 33 34 35 36 37 38 39 --> 10 19 23 32 39 45 52 54
// 40 41 42 43 44 45 46 47 20 22 33 38 46 51 55 60
// 48 49 50 51 52 53 54 55 21 34 37 47 50 56 59 61
// 56 57 58 59 60 61 62 63 35 36 48 49 57 58 62 63
//
// Which looks like a mess, right?
//
// Now, check out the NE/SW diagonals of (A). Along those lines,
// we have runs of contiguous values! If we rewrite (A) a bit, we get:
//
// 0
// 1 2
// 5 4 3
// 6 7 8 9
// 14 13 12 11 10
// 15 16 17 18 19 20
// 27 26 25 24 23 22 21 (B)
// 28 29 30 31 32 33 34 35
// 42 41 40 39 38 37 36
// 43 44 45 46 47 48
// 53 52 51 50 49
// 54 55 56 57
// 60 59 58
// 61 62
// 63
//
// In this ordering, the columns are the rows (A). If we can 'transpose'
// (B), we'll achieve our goal. But we want this to fit nicely into
// xmm registers and still be able to load large runs efficiently.
// Also, notice that the odd rows are in ascending order, while
// the even rows are in descending order.
//
// If we 'fold' the bottom half up into the top, we can preserve ordered
// runs accross rows, and still keep all the correct values in columns.
// After transposing, we'll need to rotate things back into place.
// This gives us:
//
// 0 | 42 41 40 39 38 37 36
// 1 2 | 43 44 45 46 47 48
// 5 4 3 | 53 52 51 50 49
// 6 7 8 9 | 54 55 56 57 (C)
// 14 13 12 11 10 | 60 59 58
// 15 16 17 18 19 20 | 61 62
// 27 26 25 24 23 22 21 | 61
// 28 29 30 31 32 33 34 35
//
// But hang on. We still have the backwards descending rows to deal with.
// Lets reverse the even rows so that all values are in ascending order
//
// 36 37 38 39 40 41 42 | 0
// 1 2 | 43 44 45 46 47 48
// 49 50 51 52 53 | 3 4 5
// 6 7 8 9 | 54 55 56 57 (D)
// 58 59 60 | 10 11 12 13 14
// 15 16 17 18 19 20 | 61 62
// 61 | 21 22 23 24 25 26 27
// 28 29 30 31 32 33 34 35
//
// If we can form (D), we will then:
// 1) Reverse the even rows
// 2) Transpose
// 3) Rotate the rows
//
// and we'll have (A).
//
void
fromHalfZigZag_f16c (unsigned short *src, float *dst)
{
#if defined IMF_HAVE_GCC_INLINEASM_64
__asm__
/* x3 <- 0
* x8 <- [ 0- 7]
* x6 <- [56-63]
* x9 <- [21-28]
* x7 <- [28-35]
* x3 <- [ 6- 9] (lower half) */
("vpxor %%xmm3, %%xmm3, %%xmm3 \n"
"vmovdqa (%0), %%xmm8 \n"
"vmovdqa 112(%0), %%xmm6 \n"
"vmovdqu 42(%0), %%xmm9 \n"
"vmovdqu 56(%0), %%xmm7 \n"
"vmovq 12(%0), %%xmm3 \n"
/* Setup rows 0-2 of A in xmm0-xmm2
* x1 <- x8 >> 16 (1 value)
* x2 <- x8 << 32 (2 values)
* x0 <- alignr([35-42], x8, 2)
* x1 <- blend(x1, [41-48])
* x2 <- blend(x2, [49-56]) */
"vpsrldq $2, %%xmm8, %%xmm1 \n"
"vpslldq $4, %%xmm8, %%xmm2 \n"
"vpalignr $2, 70(%0), %%xmm8, %%xmm0 \n"
"vpblendw $0xfc, 82(%0), %%xmm1, %%xmm1 \n"
"vpblendw $0x1f, 98(%0), %%xmm2, %%xmm2 \n"
/* Setup rows 4-6 of A in xmm4-xmm6
* x4 <- x6 >> 32 (2 values)
* x5 <- x6 << 16 (1 value)
* x6 <- alignr(x6,x9,14)
* x4 <- blend(x4, [ 7-14])
* x5 <- blend(x5, [15-22]) */
"vpsrldq $4, %%xmm6, %%xmm4 \n"
"vpslldq $2, %%xmm6, %%xmm5 \n"
"vpalignr $14, %%xmm6, %%xmm9, %%xmm6 \n"
"vpblendw $0xf8, 14(%0), %%xmm4, %%xmm4 \n"
"vpblendw $0x3f, 30(%0), %%xmm5, %%xmm5 \n"
/* Load the upper half of row 3 into xmm3
* x3 <- [54-57] (upper half) */
"vpinsrq $1, 108(%0), %%xmm3, %%xmm3\n"
/* Reverse the even rows. We're not using PSHUFB as
* that requires loading an extra constant all the time,
* and we're alreadly pretty memory bound.
*/
"vpshuflw $0x1b, %%xmm0, %%xmm0 \n"
"vpshuflw $0x1b, %%xmm2, %%xmm2 \n"
"vpshuflw $0x1b, %%xmm4, %%xmm4 \n"
"vpshuflw $0x1b, %%xmm6, %%xmm6 \n"
"vpshufhw $0x1b, %%xmm0, %%xmm0 \n"
"vpshufhw $0x1b, %%xmm2, %%xmm2 \n"
"vpshufhw $0x1b, %%xmm4, %%xmm4 \n"
"vpshufhw $0x1b, %%xmm6, %%xmm6 \n"
"vpshufd $0x4e, %%xmm0, %%xmm0 \n"
"vpshufd $0x4e, %%xmm2, %%xmm2 \n"
"vpshufd $0x4e, %%xmm4, %%xmm4 \n"
"vpshufd $0x4e, %%xmm6, %%xmm6 \n"
/* Transpose xmm0-xmm7 into xmm8-xmm15 */
"vpunpcklwd %%xmm1, %%xmm0, %%xmm8 \n"
"vpunpcklwd %%xmm3, %%xmm2, %%xmm9 \n"
"vpunpcklwd %%xmm5, %%xmm4, %%xmm10 \n"
"vpunpcklwd %%xmm7, %%xmm6, %%xmm11 \n"
"vpunpckhwd %%xmm1, %%xmm0, %%xmm12 \n"
"vpunpckhwd %%xmm3, %%xmm2, %%xmm13 \n"
"vpunpckhwd %%xmm5, %%xmm4, %%xmm14 \n"
"vpunpckhwd %%xmm7, %%xmm6, %%xmm15 \n"
"vpunpckldq %%xmm9, %%xmm8, %%xmm0 \n"
"vpunpckldq %%xmm11, %%xmm10, %%xmm1 \n"
"vpunpckhdq %%xmm9, %%xmm8, %%xmm2 \n"
"vpunpckhdq %%xmm11, %%xmm10, %%xmm3 \n"
"vpunpckldq %%xmm13, %%xmm12, %%xmm4 \n"
"vpunpckldq %%xmm15, %%xmm14, %%xmm5 \n"
"vpunpckhdq %%xmm13, %%xmm12, %%xmm6 \n"
"vpunpckhdq %%xmm15, %%xmm14, %%xmm7 \n"
"vpunpcklqdq %%xmm1, %%xmm0, %%xmm8 \n"
"vpunpckhqdq %%xmm1, %%xmm0, %%xmm9 \n"
"vpunpcklqdq %%xmm3, %%xmm2, %%xmm10 \n"
"vpunpckhqdq %%xmm3, %%xmm2, %%xmm11 \n"
"vpunpcklqdq %%xmm4, %%xmm5, %%xmm12 \n"
"vpunpckhqdq %%xmm5, %%xmm4, %%xmm13 \n"
"vpunpcklqdq %%xmm7, %%xmm6, %%xmm14 \n"
"vpunpckhqdq %%xmm7, %%xmm6, %%xmm15 \n"
/* Rotate the rows to get the correct final order.
* Rotating xmm12 isn't needed, as we can handle
* the rotation in the PUNPCKLQDQ above. Rotating
* xmm8 isn't needed as it's already in the right order
*/
"vpalignr $2, %%xmm9, %%xmm9, %%xmm9 \n"
"vpalignr $4, %%xmm10, %%xmm10, %%xmm10 \n"
"vpalignr $6, %%xmm11, %%xmm11, %%xmm11 \n"
"vpalignr $10, %%xmm13, %%xmm13, %%xmm13 \n"
"vpalignr $12, %%xmm14, %%xmm14, %%xmm14 \n"
"vpalignr $14, %%xmm15, %%xmm15, %%xmm15 \n"
/* Convert from half -> float */
"vcvtph2ps %%xmm8, %%ymm8 \n"
"vcvtph2ps %%xmm9, %%ymm9 \n"
"vcvtph2ps %%xmm10, %%ymm10 \n"
"vcvtph2ps %%xmm11, %%ymm11 \n"
"vcvtph2ps %%xmm12, %%ymm12 \n"
"vcvtph2ps %%xmm13, %%ymm13 \n"
"vcvtph2ps %%xmm14, %%ymm14 \n"
"vcvtph2ps %%xmm15, %%ymm15 \n"
/* Move float values to dst */
"vmovaps %%ymm8, (%1) \n"
"vmovaps %%ymm9, 32(%1) \n"
"vmovaps %%ymm10, 64(%1) \n"
"vmovaps %%ymm11, 96(%1) \n"
"vmovaps %%ymm12, 128(%1) \n"
"vmovaps %%ymm13, 160(%1) \n"
"vmovaps %%ymm14, 192(%1) \n"
"vmovaps %%ymm15, 224(%1) \n"
#ifndef __AVX__
"vzeroupper \n"
#endif /* __AVX__ */
: /* Output */
: /* Input */ "r"(src), "r"(dst)
: /* Clobber */ "memory",
#ifndef __AVX__
"%xmm0", "%xmm1", "%xmm2", "%xmm3",
"%xmm4", "%xmm5", "%xmm6", "%xmm7",
"%xmm8", "%xmm9", "%xmm10", "%xmm11",
"%xmm12", "%xmm13", "%xmm14", "%xmm15"
#else
"%ymm0", "%ymm1", "%ymm2", "%ymm3",
"%ymm4", "%ymm5", "%ymm6", "%ymm7",
"%ymm8", "%ymm9", "%ymm10", "%ymm11",
"%ymm12", "%ymm13", "%ymm14", "%ymm15"
#endif /* __AVX__ */
);
#else
fromHalfZigZag_scalar(src, dst);
#endif /* defined IMF_HAVE_GCC_INLINEASM_64 */
}
//
// Inverse 8x8 DCT, only inverting the DC. This assumes that
// all AC frequencies are 0.
//
#ifndef IMF_HAVE_SSE2
void
dctInverse8x8DcOnly (float *data)
{
float val = data[0] * 3.535536e-01f * 3.535536e-01f;
for (int i = 0; i < 64; ++i)
data[i] = val;
}
#else /* IMF_HAVE_SSE2 */
void
dctInverse8x8DcOnly (float *data)
{
__m128 src = _mm_set1_ps (data[0] * 3.535536e-01f * 3.535536e-01f);
__m128 *dst = (__m128 *)data;
for (int i = 0; i < 16; ++i)
dst[i] = src;
}
#endif /* IMF_HAVE_SSE2 */
//
// Full 8x8 Inverse DCT:
//
// Simple inverse DCT on an 8x8 block, with scalar ops only.
// Operates on data in-place.
//
// This is based on the iDCT formuation (y = frequency domain,
// x = spatial domain)
//
// [x0] [ ][y0] [ ][y1]
// [x1] = [ M1 ][y2] + [ M2 ][y3]
// [x2] [ ][y4] [ ][y5]
// [x3] [ ][y6] [ ][y7]
//
// [x7] [ ][y0] [ ][y1]
// [x6] = [ M1 ][y2] - [ M2 ][y3]
// [x5] [ ][y4] [ ][y5]
// [x4] [ ][y6] [ ][y7]
//
// where M1: M2:
//
// [a c a f] [b d e g]
// [a f -a -c] [d -g -b -e]
// [a -f -a c] [e -b g d]
// [a -c a -f] [g -e d -b]
//
// and the constants are as defined below..
//
// If you know how many of the lower rows are zero, that can
// be passed in to help speed things up. If you don't know,
// just set zeroedRows=0.
//
//
// Default implementation
//
template <int zeroedRows>
void
dctInverse8x8_scalar (float *data)
{
const float a = .5f * cosf (3.14159f / 4.0f);
const float b = .5f * cosf (3.14159f / 16.0f);
const float c = .5f * cosf (3.14159f / 8.0f);
const float d = .5f * cosf (3.f*3.14159f / 16.0f);
const float e = .5f * cosf (5.f*3.14159f / 16.0f);
const float f = .5f * cosf (3.f*3.14159f / 8.0f);
const float g = .5f * cosf (7.f*3.14159f / 16.0f);
float alpha[4], beta[4], theta[4], gamma[4];
float *rowPtr = NULL;
//
// First pass - row wise.
//
// This looks less-compact than the description above in
// an attempt to fold together common sub-expressions.
//
for (int row = 0; row < 8 - zeroedRows; ++row)
{
rowPtr = data + row * 8;
alpha[0] = c * rowPtr[2];
alpha[1] = f * rowPtr[2];
alpha[2] = c * rowPtr[6];
alpha[3] = f * rowPtr[6];
beta[0] = b * rowPtr[1] + d * rowPtr[3] + e * rowPtr[5] + g * rowPtr[7];
beta[1] = d * rowPtr[1] - g * rowPtr[3] - b * rowPtr[5] - e * rowPtr[7];
beta[2] = e * rowPtr[1] - b * rowPtr[3] + g * rowPtr[5] + d * rowPtr[7];
beta[3] = g * rowPtr[1] - e * rowPtr[3] + d * rowPtr[5] - b * rowPtr[7];
theta[0] = a * (rowPtr[0] + rowPtr[4]);
theta[3] = a * (rowPtr[0] - rowPtr[4]);
theta[1] = alpha[0] + alpha[3];
theta[2] = alpha[1] - alpha[2];
gamma[0] = theta[0] + theta[1];
gamma[1] = theta[3] + theta[2];
gamma[2] = theta[3] - theta[2];
gamma[3] = theta[0] - theta[1];
rowPtr[0] = gamma[0] + beta[0];
rowPtr[1] = gamma[1] + beta[1];
rowPtr[2] = gamma[2] + beta[2];
rowPtr[3] = gamma[3] + beta[3];
rowPtr[4] = gamma[3] - beta[3];
rowPtr[5] = gamma[2] - beta[2];
rowPtr[6] = gamma[1] - beta[1];
rowPtr[7] = gamma[0] - beta[0];
}
//
// Second pass - column wise.
//
for (int column = 0; column < 8; ++column)
{
alpha[0] = c * data[16+column];
alpha[1] = f * data[16+column];
alpha[2] = c * data[48+column];
alpha[3] = f * data[48+column];
beta[0] = b * data[8+column] + d * data[24+column] +
e * data[40+column] + g * data[56+column];
beta[1] = d * data[8+column] - g * data[24+column] -
b * data[40+column] - e * data[56+column];
beta[2] = e * data[8+column] - b * data[24+column] +
g * data[40+column] + d * data[56+column];
beta[3] = g * data[8+column] - e * data[24+column] +
d * data[40+column] - b * data[56+column];
theta[0] = a * (data[column] + data[32+column]);
theta[3] = a * (data[column] - data[32+column]);
theta[1] = alpha[0] + alpha[3];
theta[2] = alpha[1] - alpha[2];
gamma[0] = theta[0] + theta[1];
gamma[1] = theta[3] + theta[2];
gamma[2] = theta[3] - theta[2];
gamma[3] = theta[0] - theta[1];
data[ column] = gamma[0] + beta[0];
data[ 8 + column] = gamma[1] + beta[1];
data[16 + column] = gamma[2] + beta[2];
data[24 + column] = gamma[3] + beta[3];
data[32 + column] = gamma[3] - beta[3];
data[40 + column] = gamma[2] - beta[2];
data[48 + column] = gamma[1] - beta[1];
data[56 + column] = gamma[0] - beta[0];
}
}
//
// SSE2 Implementation
//
template <int zeroedRows>
void
dctInverse8x8_sse2 (float *data)
{
#ifdef IMF_HAVE_SSE2
__m128 a = {3.535536e-01f,3.535536e-01f,3.535536e-01f,3.535536e-01f};
__m128 b = {4.903927e-01f,4.903927e-01f,4.903927e-01f,4.903927e-01f};
__m128 c = {4.619398e-01f,4.619398e-01f,4.619398e-01f,4.619398e-01f};
__m128 d = {4.157349e-01f,4.157349e-01f,4.157349e-01f,4.157349e-01f};
__m128 e = {2.777855e-01f,2.777855e-01f,2.777855e-01f,2.777855e-01f};
__m128 f = {1.913422e-01f,1.913422e-01f,1.913422e-01f,1.913422e-01f};
__m128 g = {9.754573e-02f,9.754573e-02f,9.754573e-02f,9.754573e-02f};
__m128 c0 = {3.535536e-01f, 3.535536e-01f, 3.535536e-01f, 3.535536e-01f};
__m128 c1 = {4.619398e-01f, 1.913422e-01f,-1.913422e-01f,-4.619398e-01f};
__m128 c2 = {3.535536e-01f,-3.535536e-01f,-3.535536e-01f, 3.535536e-01f};
__m128 c3 = {1.913422e-01f,-4.619398e-01f, 4.619398e-01f,-1.913422e-01f};
__m128 c4 = {4.903927e-01f, 4.157349e-01f, 2.777855e-01f, 9.754573e-02f};
__m128 c5 = {4.157349e-01f,-9.754573e-02f,-4.903927e-01f,-2.777855e-01f};
__m128 c6 = {2.777855e-01f,-4.903927e-01f, 9.754573e-02f, 4.157349e-01f};
__m128 c7 = {9.754573e-02f,-2.777855e-01f, 4.157349e-01f,-4.903927e-01f};
__m128 *srcVec = (__m128 *)data;
__m128 x[8], evenSum, oddSum;
__m128 in[8], alpha[4], beta[4], theta[4], gamma[4];
//
// Rows -
//
// Treat this just like matrix-vector multiplication. The
// trick is to note that:
//
// [M00 M01 M02 M03][v0] [(v0 M00) + (v1 M01) + (v2 M02) + (v3 M03)]
// [M10 M11 M12 M13][v1] = [(v0 M10) + (v1 M11) + (v2 M12) + (v3 M13)]
// [M20 M21 M22 M23][v2] [(v0 M20) + (v1 M21) + (v2 M22) + (v3 M23)]
// [M30 M31 M32 M33][v3] [(v0 M30) + (v1 M31) + (v2 M32) + (v3 M33)]
//
// Then, we can fill a register with v_i and multiply by the i-th column
// of M, accumulating across all i-s.
//
// The kids refer to the populating of a register with a single value
// "broadcasting", and it can be done with a shuffle instruction. It
// seems to be the slowest part of the whole ordeal.
//
// Our matrix columns are stored above in c0-c7. c0-3 make up M1, and
// c4-7 are from M2.
//
#define DCT_INVERSE_8x8_SS2_ROW_LOOP(i) \
/* \
* Broadcast the components of the row \
*/ \
\
x[0] = _mm_shuffle_ps (srcVec[2 * i], \
srcVec[2 * i], \
_MM_SHUFFLE (0, 0, 0, 0)); \
\
x[1] = _mm_shuffle_ps (srcVec[2 * i], \
srcVec[2 * i], \
_MM_SHUFFLE (1, 1, 1, 1)); \
\
x[2] = _mm_shuffle_ps (srcVec[2 * i], \
srcVec[2 * i], \
_MM_SHUFFLE (2, 2, 2, 2)); \
\
x[3] = _mm_shuffle_ps (srcVec[2 * i], \
srcVec[2 * i], \
_MM_SHUFFLE (3, 3, 3, 3)); \
\
x[4] = _mm_shuffle_ps (srcVec[2 * i + 1], \
srcVec[2 * i + 1], \
_MM_SHUFFLE (0, 0, 0, 0)); \
\
x[5] = _mm_shuffle_ps (srcVec[2 * i + 1], \
srcVec[2 * i + 1], \
_MM_SHUFFLE (1, 1, 1, 1)); \
\
x[6] = _mm_shuffle_ps (srcVec[2 * i + 1], \
srcVec[2 * i + 1], \
_MM_SHUFFLE (2, 2, 2, 2)); \
\
x[7] = _mm_shuffle_ps (srcVec[2 * i + 1], \
srcVec[2 * i + 1], \
_MM_SHUFFLE (3, 3, 3, 3)); \
/* \
* Multiply the components by each column of the matrix \
*/ \
\
x[0] = _mm_mul_ps (x[0], c0); \
x[2] = _mm_mul_ps (x[2], c1); \
x[4] = _mm_mul_ps (x[4], c2); \
x[6] = _mm_mul_ps (x[6], c3); \
\
x[1] = _mm_mul_ps (x[1], c4); \
x[3] = _mm_mul_ps (x[3], c5); \
x[5] = _mm_mul_ps (x[5], c6); \
x[7] = _mm_mul_ps (x[7], c7); \
\
/* \
* Add across \
*/ \
\
evenSum = _mm_setzero_ps(); \
evenSum = _mm_add_ps (evenSum, x[0]); \
evenSum = _mm_add_ps (evenSum, x[2]); \
evenSum = _mm_add_ps (evenSum, x[4]); \
evenSum = _mm_add_ps (evenSum, x[6]); \
\
oddSum = _mm_setzero_ps(); \
oddSum = _mm_add_ps (oddSum, x[1]); \
oddSum = _mm_add_ps (oddSum, x[3]); \
oddSum = _mm_add_ps (oddSum, x[5]); \
oddSum = _mm_add_ps (oddSum, x[7]); \
\
/* \
* Final Sum: \
* out [0, 1, 2, 3] = evenSum + oddSum \
* out [7, 6, 5, 4] = evenSum - oddSum \
*/ \
\
srcVec[2 * i] = _mm_add_ps (evenSum, oddSum); \
srcVec[2 * i + 1] = _mm_sub_ps (evenSum, oddSum); \
srcVec[2 * i + 1] = _mm_shuffle_ps (srcVec[2 * i + 1], \
srcVec[2 * i + 1], \
_MM_SHUFFLE (0, 1, 2, 3));
switch (zeroedRows)
{
case 0:
default:
DCT_INVERSE_8x8_SS2_ROW_LOOP (0)
DCT_INVERSE_8x8_SS2_ROW_LOOP (1)
DCT_INVERSE_8x8_SS2_ROW_LOOP (2)
DCT_INVERSE_8x8_SS2_ROW_LOOP (3)
DCT_INVERSE_8x8_SS2_ROW_LOOP (4)
DCT_INVERSE_8x8_SS2_ROW_LOOP (5)
DCT_INVERSE_8x8_SS2_ROW_LOOP (6)
DCT_INVERSE_8x8_SS2_ROW_LOOP (7)
break;
case 1:
DCT_INVERSE_8x8_SS2_ROW_LOOP (0)
DCT_INVERSE_8x8_SS2_ROW_LOOP (1)
DCT_INVERSE_8x8_SS2_ROW_LOOP (2)
DCT_INVERSE_8x8_SS2_ROW_LOOP (3)
DCT_INVERSE_8x8_SS2_ROW_LOOP (4)
DCT_INVERSE_8x8_SS2_ROW_LOOP (5)
DCT_INVERSE_8x8_SS2_ROW_LOOP (6)
break;
case 2:
DCT_INVERSE_8x8_SS2_ROW_LOOP (0)
DCT_INVERSE_8x8_SS2_ROW_LOOP (1)
DCT_INVERSE_8x8_SS2_ROW_LOOP (2)
DCT_INVERSE_8x8_SS2_ROW_LOOP (3)
DCT_INVERSE_8x8_SS2_ROW_LOOP (4)
DCT_INVERSE_8x8_SS2_ROW_LOOP (5)
break;
case 3:
DCT_INVERSE_8x8_SS2_ROW_LOOP (0)
DCT_INVERSE_8x8_SS2_ROW_LOOP (1)
DCT_INVERSE_8x8_SS2_ROW_LOOP (2)
DCT_INVERSE_8x8_SS2_ROW_LOOP (3)
DCT_INVERSE_8x8_SS2_ROW_LOOP (4)
break;
case 4:
DCT_INVERSE_8x8_SS2_ROW_LOOP (0)
DCT_INVERSE_8x8_SS2_ROW_LOOP (1)
DCT_INVERSE_8x8_SS2_ROW_LOOP (2)
DCT_INVERSE_8x8_SS2_ROW_LOOP (3)
break;
case 5:
DCT_INVERSE_8x8_SS2_ROW_LOOP (0)
DCT_INVERSE_8x8_SS2_ROW_LOOP (1)
DCT_INVERSE_8x8_SS2_ROW_LOOP (2)
break;
case 6:
DCT_INVERSE_8x8_SS2_ROW_LOOP (0)
DCT_INVERSE_8x8_SS2_ROW_LOOP (1)
break;
case 7:
DCT_INVERSE_8x8_SS2_ROW_LOOP (0)
break;
}
//
// Columns -
//
// This is slightly more straightforward, if less readable. Here
// we just operate on 4 columns at a time, in two batches.
//
// The slight mess is to try and cache sub-expressions, which
// we ignore in the row-wise pass.
//
for (int col = 0; col < 2; ++col)
{
for (int i = 0; i < 8; ++i)
in[i] = srcVec[2 * i + col];
alpha[0] = _mm_mul_ps (c, in[2]);
alpha[1] = _mm_mul_ps (f, in[2]);
alpha[2] = _mm_mul_ps (c, in[6]);
alpha[3] = _mm_mul_ps (f, in[6]);
beta[0] = _mm_add_ps (_mm_add_ps (_mm_mul_ps (in[1], b),
_mm_mul_ps (in[3], d)),
_mm_add_ps (_mm_mul_ps (in[5], e),
_mm_mul_ps (in[7], g)));
beta[1] = _mm_sub_ps (_mm_sub_ps (_mm_mul_ps (in[1], d),
_mm_mul_ps (in[3], g)),
_mm_add_ps (_mm_mul_ps (in[5], b),
_mm_mul_ps (in[7], e)));
beta[2] = _mm_add_ps (_mm_sub_ps (_mm_mul_ps (in[1], e),
_mm_mul_ps (in[3], b)),
_mm_add_ps (_mm_mul_ps (in[5], g),
_mm_mul_ps (in[7], d)));
beta[3] = _mm_add_ps (_mm_sub_ps (_mm_mul_ps (in[1], g),
_mm_mul_ps (in[3], e)),
_mm_sub_ps (_mm_mul_ps (in[5], d),
_mm_mul_ps (in[7], b)));
theta[0] = _mm_mul_ps (a, _mm_add_ps (in[0], in[4]));
theta[3] = _mm_mul_ps (a, _mm_sub_ps (in[0], in[4]));
theta[1] = _mm_add_ps (alpha[0], alpha[3]);
theta[2] = _mm_sub_ps (alpha[1], alpha[2]);
gamma[0] = _mm_add_ps (theta[0], theta[1]);
gamma[1] = _mm_add_ps (theta[3], theta[2]);
gamma[2] = _mm_sub_ps (theta[3], theta[2]);
gamma[3] = _mm_sub_ps (theta[0], theta[1]);
srcVec[ col] = _mm_add_ps (gamma[0], beta[0]);
srcVec[2+col] = _mm_add_ps (gamma[1], beta[1]);
srcVec[4+col] = _mm_add_ps (gamma[2], beta[2]);
srcVec[6+col] = _mm_add_ps (gamma[3], beta[3]);
srcVec[ 8+col] = _mm_sub_ps (gamma[3], beta[3]);
srcVec[10+col] = _mm_sub_ps (gamma[2], beta[2]);
srcVec[12+col] = _mm_sub_ps (gamma[1], beta[1]);
srcVec[14+col] = _mm_sub_ps (gamma[0], beta[0]);
}
#else /* IMF_HAVE_SSE2 */
dctInverse8x8_scalar<zeroedRows> (data);
#endif /* IMF_HAVE_SSE2 */
}
//
// AVX Implementation
//
#define STR(A) #A
#define IDCT_AVX_SETUP_2_ROWS(_DST0, _DST1, _TMP0, _TMP1, \
_OFF00, _OFF01, _OFF10, _OFF11) \
"vmovaps " STR(_OFF00) "(%0), %%xmm" STR(_TMP0) " \n" \
"vmovaps " STR(_OFF01) "(%0), %%xmm" STR(_TMP1) " \n" \
" \n" \
"vinsertf128 $1, " STR(_OFF10) "(%0), %%ymm" STR(_TMP0) ", %%ymm" STR(_TMP0) " \n" \
"vinsertf128 $1, " STR(_OFF11) "(%0), %%ymm" STR(_TMP1) ", %%ymm" STR(_TMP1) " \n" \
" \n" \
"vunpcklpd %%ymm" STR(_TMP1) ", %%ymm" STR(_TMP0) ", %%ymm" STR(_DST0) " \n" \
"vunpckhpd %%ymm" STR(_TMP1) ", %%ymm" STR(_TMP0) ", %%ymm" STR(_DST1) " \n" \
" \n" \
"vunpcklps %%ymm" STR(_DST1) ", %%ymm" STR(_DST0) ", %%ymm" STR(_TMP0) " \n" \
"vunpckhps %%ymm" STR(_DST1) ", %%ymm" STR(_DST0) ", %%ymm" STR(_TMP1) " \n" \
" \n" \
"vunpcklpd %%ymm" STR(_TMP1) ", %%ymm" STR(_TMP0) ", %%ymm" STR(_DST0) " \n" \
"vunpckhpd %%ymm" STR(_TMP1) ", %%ymm" STR(_TMP0) ", %%ymm" STR(_DST1) " \n"
#define IDCT_AVX_MMULT_ROWS(_SRC) \
/* Broadcast the source values into y12-y15 */ \
"vpermilps $0x00, " STR(_SRC) ", %%ymm12 \n" \
"vpermilps $0x55, " STR(_SRC) ", %%ymm13 \n" \
"vpermilps $0xaa, " STR(_SRC) ", %%ymm14 \n" \
"vpermilps $0xff, " STR(_SRC) ", %%ymm15 \n" \
\
/* Multiple coefs and the broadcasted values */ \
"vmulps %%ymm12, %%ymm8, %%ymm12 \n" \
"vmulps %%ymm13, %%ymm9, %%ymm13 \n" \
"vmulps %%ymm14, %%ymm10, %%ymm14 \n" \
"vmulps %%ymm15, %%ymm11, %%ymm15 \n" \
\
/* Accumulate the result back into the source */ \
"vaddps %%ymm13, %%ymm12, %%ymm12 \n" \
"vaddps %%ymm15, %%ymm14, %%ymm14 \n" \
"vaddps %%ymm14, %%ymm12, " STR(_SRC) "\n"
#define IDCT_AVX_EO_TO_ROW_HALVES(_EVEN, _ODD, _FRONT, _BACK) \
"vsubps " STR(_ODD) "," STR(_EVEN) "," STR(_BACK) "\n" \
"vaddps " STR(_ODD) "," STR(_EVEN) "," STR(_FRONT) "\n" \
/* Reverse the back half */ \
"vpermilps $0x1b," STR(_BACK) "," STR(_BACK) "\n"
/* In order to allow for path paths when we know certain rows
* of the 8x8 block are zero, most of the body of the DCT is
* in the following macro. Statements are wrapped in a ROWn()
* macro, where n is the lowest row in the 8x8 block in which
* they depend.
*
* This should work for the cases where we have 2-8 full rows.
* the 1-row case is special, and we'll handle it seperately.
*/
#define IDCT_AVX_BODY \
/* ==============================================
* Row 1D DCT
* ----------------------------------------------
*/ \
\
/* Setup for the row-oriented 1D DCT. Assuming that (%0) holds
* the row-major 8x8 block, load ymm0-3 with the even columns
* and ymm4-7 with the odd columns. The lower half of the ymm
* holds one row, while the upper half holds the next row.
*
* If our source is:
* a0 a1 a2 a3 a4 a5 a6 a7
* b0 b1 b2 b3 b4 b5 b6 b7
*
* We'll be forming:
* a0 a2 a4 a6 b0 b2 b4 b6
* a1 a3 a5 a7 b1 b3 b5 b7
*/ \
ROW0( IDCT_AVX_SETUP_2_ROWS(0, 4, 14, 15, 0, 16, 32, 48) ) \
ROW2( IDCT_AVX_SETUP_2_ROWS(1, 5, 12, 13, 64, 80, 96, 112) ) \
ROW4( IDCT_AVX_SETUP_2_ROWS(2, 6, 10, 11, 128, 144, 160, 176) ) \
ROW6( IDCT_AVX_SETUP_2_ROWS(3, 7, 8, 9, 192, 208, 224, 240) ) \
\
/* Multiple the even columns (ymm0-3) by the matrix M1
* storing the results back in ymm0-3
*
* Assume that (%1) holds the matrix in column major order
*/ \
"vbroadcastf128 (%1), %%ymm8 \n" \
"vbroadcastf128 16(%1), %%ymm9 \n" \
"vbroadcastf128 32(%1), %%ymm10 \n" \
"vbroadcastf128 48(%1), %%ymm11 \n" \
\
ROW0( IDCT_AVX_MMULT_ROWS(%%ymm0) ) \
ROW2( IDCT_AVX_MMULT_ROWS(%%ymm1) ) \
ROW4( IDCT_AVX_MMULT_ROWS(%%ymm2) ) \
ROW6( IDCT_AVX_MMULT_ROWS(%%ymm3) ) \
\
/* Repeat, but with the odd columns (ymm4-7) and the
* matrix M2
*/ \
"vbroadcastf128 64(%1), %%ymm8 \n" \
"vbroadcastf128 80(%1), %%ymm9 \n" \
"vbroadcastf128 96(%1), %%ymm10 \n" \
"vbroadcastf128 112(%1), %%ymm11 \n" \
\
ROW0( IDCT_AVX_MMULT_ROWS(%%ymm4) ) \
ROW2( IDCT_AVX_MMULT_ROWS(%%ymm5) ) \
ROW4( IDCT_AVX_MMULT_ROWS(%%ymm6) ) \
ROW6( IDCT_AVX_MMULT_ROWS(%%ymm7) ) \
\
/* Sum the M1 (ymm0-3) and M2 (ymm4-7) results to get the
* front halves of the results, and difference to get the
* back halves. The front halfs end up in ymm0-3, the back
* halves end up in ymm12-15.
*/ \
ROW0( IDCT_AVX_EO_TO_ROW_HALVES(%%ymm0, %%ymm4, %%ymm0, %%ymm12) ) \
ROW2( IDCT_AVX_EO_TO_ROW_HALVES(%%ymm1, %%ymm5, %%ymm1, %%ymm13) ) \
ROW4( IDCT_AVX_EO_TO_ROW_HALVES(%%ymm2, %%ymm6, %%ymm2, %%ymm14) ) \
ROW6( IDCT_AVX_EO_TO_ROW_HALVES(%%ymm3, %%ymm7, %%ymm3, %%ymm15) ) \
\
/* Reassemble the rows halves into ymm0-7 */ \
ROW7( "vperm2f128 $0x13, %%ymm3, %%ymm15, %%ymm7 \n" ) \
ROW6( "vperm2f128 $0x02, %%ymm3, %%ymm15, %%ymm6 \n" ) \
ROW5( "vperm2f128 $0x13, %%ymm2, %%ymm14, %%ymm5 \n" ) \
ROW4( "vperm2f128 $0x02, %%ymm2, %%ymm14, %%ymm4 \n" ) \
ROW3( "vperm2f128 $0x13, %%ymm1, %%ymm13, %%ymm3 \n" ) \
ROW2( "vperm2f128 $0x02, %%ymm1, %%ymm13, %%ymm2 \n" ) \
ROW1( "vperm2f128 $0x13, %%ymm0, %%ymm12, %%ymm1 \n" ) \
ROW0( "vperm2f128 $0x02, %%ymm0, %%ymm12, %%ymm0 \n" ) \
\
\
/* ==============================================
* Column 1D DCT
* ----------------------------------------------
*/ \
\
/* Rows should be in ymm0-7, and M2 columns should still be
* preserved in ymm8-11. M2 has 4 unique values (and +-
* versions of each), and all (positive) values appear in
* the first column (and row), which is in ymm8.
*
* For the column-wise DCT, we need to:
* 1) Broadcast each element a row of M2 into 4 vectors
* 2) Multiple the odd rows (ymm1,3,5,7) by the broadcasts.
* 3) Accumulate into ymm12-15 for the odd outputs.
*
* Instead of doing 16 broadcasts for each element in M2,
* do 4, filling y8-11 with:
*
* ymm8: [ b b b b | b b b b ]
* ymm9: [ d d d d | d d d d ]
* ymm10: [ e e e e | e e e e ]
* ymm11: [ g g g g | g g g g ]
*
* And deal with the negative values by subtracting during accum.
*/ \
"vpermilps $0xff, %%ymm8, %%ymm11 \n" \
"vpermilps $0xaa, %%ymm8, %%ymm10 \n" \
"vpermilps $0x55, %%ymm8, %%ymm9 \n" \
"vpermilps $0x00, %%ymm8, %%ymm8 \n" \
\
/* This one is easy, since we have ymm12-15 open for scratch
* ymm12 = b ymm1 + d ymm3 + e ymm5 + g ymm7
*/ \
ROW1( "vmulps %%ymm1, %%ymm8, %%ymm12 \n" ) \
ROW3( "vmulps %%ymm3, %%ymm9, %%ymm13 \n" ) \
ROW5( "vmulps %%ymm5, %%ymm10, %%ymm14 \n" ) \
ROW7( "vmulps %%ymm7, %%ymm11, %%ymm15 \n" ) \
\
ROW3( "vaddps %%ymm12, %%ymm13, %%ymm12 \n" ) \
ROW7( "vaddps %%ymm14, %%ymm15, %%ymm14 \n" ) \
ROW5( "vaddps %%ymm12, %%ymm14, %%ymm12 \n" ) \
\
/* Tricker, since only y13-15 are open for scratch
* ymm13 = d ymm1 - g ymm3 - b ymm5 - e ymm7
*/ \
ROW1( "vmulps %%ymm1, %%ymm9, %%ymm13 \n" ) \
ROW3( "vmulps %%ymm3, %%ymm11, %%ymm14 \n" ) \
ROW5( "vmulps %%ymm5, %%ymm8, %%ymm15 \n" ) \
\
ROW5( "vaddps %%ymm14, %%ymm15, %%ymm14 \n" ) \
ROW3( "vsubps %%ymm14, %%ymm13, %%ymm13 \n" ) \
\
ROW7( "vmulps %%ymm7, %%ymm10, %%ymm15 \n" ) \
ROW7( "vsubps %%ymm15, %%ymm13, %%ymm13 \n" ) \
\
/* Tricker still, as only y14-15 are open for scratch
* ymm14 = e ymm1 - b ymm3 + g ymm5 + d ymm7
*/ \
ROW1( "vmulps %%ymm1, %%ymm10, %%ymm14 \n" ) \
ROW3( "vmulps %%ymm3, %%ymm8, %%ymm15 \n" ) \
\
ROW3( "vsubps %%ymm15, %%ymm14, %%ymm14 \n" ) \
\
ROW5( "vmulps %%ymm5, %%ymm11, %%ymm15 \n" ) \
ROW5( "vaddps %%ymm15, %%ymm14, %%ymm14 \n" ) \
\
ROW7( "vmulps %%ymm7, %%ymm9, %%ymm15 \n" ) \
ROW7( "vaddps %%ymm15, %%ymm14, %%ymm14 \n" ) \
\
\
/* Easy, as we can blow away ymm1,3,5,7 for scratch
* ymm15 = g ymm1 - e ymm3 + d ymm5 - b ymm7
*/ \
ROW1( "vmulps %%ymm1, %%ymm11, %%ymm15 \n" ) \
ROW3( "vmulps %%ymm3, %%ymm10, %%ymm3 \n" ) \
ROW5( "vmulps %%ymm5, %%ymm9, %%ymm5 \n" ) \
ROW7( "vmulps %%ymm7, %%ymm8, %%ymm7 \n" ) \
\
ROW5( "vaddps %%ymm15, %%ymm5, %%ymm15 \n" ) \
ROW7( "vaddps %%ymm3, %%ymm7, %%ymm3 \n" ) \
ROW3( "vsubps %%ymm3, %%ymm15, %%ymm15 \n" ) \
\
\
/* Load coefs for M1. Because we're going to broadcast
* coefs, we don't need to load the actual structure from
* M1. Instead, just load enough that we can broadcast.
* There are only 6 unique values in M1, but they're in +-
* pairs, leaving only 3 unique coefs if we add and subtract
* properly.
*
* Fill ymm1 with coef[2] = [ a a c f | a a c f ]
* Broadcast ymm5 with [ f f f f | f f f f ]
* Broadcast ymm3 with [ c c c c | c c c c ]
* Broadcast ymm1 with [ a a a a | a a a a ]
*/ \
"vbroadcastf128 8(%1), %%ymm1 \n" \
"vpermilps $0xff, %%ymm1, %%ymm5 \n" \
"vpermilps $0xaa, %%ymm1, %%ymm3 \n" \
"vpermilps $0x00, %%ymm1, %%ymm1 \n" \
\
/* If we expand E = [M1] [x0 x2 x4 x6]^t, we get the following
* common expressions:
*
* E_0 = ymm8 = (a ymm0 + a ymm4) + (c ymm2 + f ymm6)
* E_3 = ymm11 = (a ymm0 + a ymm4) - (c ymm2 + f ymm6)
*
* E_1 = ymm9 = (a ymm0 - a ymm4) + (f ymm2 - c ymm6)
* E_2 = ymm10 = (a ymm0 - a ymm4) - (f ymm2 - c ymm6)
*
* Afterwards, ymm8-11 will hold the even outputs.
*/ \
\
/* ymm11 = (a ymm0 + a ymm4), ymm1 = (a ymm0 - a ymm4) */ \
ROW0( "vmulps %%ymm1, %%ymm0, %%ymm11 \n" ) \
ROW4( "vmulps %%ymm1, %%ymm4, %%ymm4 \n" ) \
ROW0( "vmovaps %%ymm11, %%ymm1 \n" ) \
ROW4( "vaddps %%ymm4, %%ymm11, %%ymm11 \n" ) \
ROW4( "vsubps %%ymm4, %%ymm1, %%ymm1 \n" ) \
\
/* ymm7 = (c ymm2 + f ymm6) */ \
ROW2( "vmulps %%ymm3, %%ymm2, %%ymm7 \n" ) \
ROW6( "vmulps %%ymm5, %%ymm6, %%ymm9 \n" ) \
ROW6( "vaddps %%ymm9, %%ymm7, %%ymm7 \n" ) \
\
/* E_0 = ymm8 = (a ymm0 + a ymm4) + (c ymm2 + f ymm6)
* E_3 = ymm11 = (a ymm0 + a ymm4) - (c ymm2 + f ymm6)
*/ \
ROW0( "vmovaps %%ymm11, %%ymm8 \n" ) \
ROW2( "vaddps %%ymm7, %%ymm8, %%ymm8 \n" ) \
ROW2( "vsubps %%ymm7, %%ymm11, %%ymm11 \n" ) \
\
/* ymm7 = (f ymm2 - c ymm6) */ \
ROW2( "vmulps %%ymm5, %%ymm2, %%ymm7 \n" ) \
ROW6( "vmulps %%ymm3, %%ymm6, %%ymm9 \n" ) \
ROW6( "vsubps %%ymm9, %%ymm7, %%ymm7 \n" ) \
\
/* E_1 = ymm9 = (a ymm0 - a ymm4) + (f ymm2 - c ymm6)
* E_2 = ymm10 = (a ymm0 - a ymm4) - (f ymm2 - c ymm6)
*/ \
ROW0( "vmovaps %%ymm1, %%ymm9 \n" ) \
ROW0( "vmovaps %%ymm1, %%ymm10 \n" ) \
ROW2( "vaddps %%ymm7, %%ymm1, %%ymm9 \n" ) \
ROW2( "vsubps %%ymm7, %%ymm1, %%ymm10 \n" ) \
\
/* Add the even (ymm8-11) and the odds (ymm12-15),
* placing the results into ymm0-7
*/ \
"vaddps %%ymm12, %%ymm8, %%ymm0 \n" \
"vaddps %%ymm13, %%ymm9, %%ymm1 \n" \
"vaddps %%ymm14, %%ymm10, %%ymm2 \n" \
"vaddps %%ymm15, %%ymm11, %%ymm3 \n" \
\
"vsubps %%ymm12, %%ymm8, %%ymm7 \n" \
"vsubps %%ymm13, %%ymm9, %%ymm6 \n" \
"vsubps %%ymm14, %%ymm10, %%ymm5 \n" \
"vsubps %%ymm15, %%ymm11, %%ymm4 \n" \
\
/* Copy out the results from ymm0-7 */ \
"vmovaps %%ymm0, (%0) \n" \
"vmovaps %%ymm1, 32(%0) \n" \
"vmovaps %%ymm2, 64(%0) \n" \
"vmovaps %%ymm3, 96(%0) \n" \
"vmovaps %%ymm4, 128(%0) \n" \
"vmovaps %%ymm5, 160(%0) \n" \
"vmovaps %%ymm6, 192(%0) \n" \
"vmovaps %%ymm7, 224(%0) \n"
/* Output, input, and clobber (OIC) sections of the inline asm */
#define IDCT_AVX_OIC(_IN0) \
: /* Output */ \
: /* Input */ "r"(_IN0), "r"(sAvxCoef) \
: /* Clobber */ "memory", \
"%xmm0", "%xmm1", "%xmm2", "%xmm3", \
"%xmm4", "%xmm5", "%xmm6", "%xmm7", \
"%xmm8", "%xmm9", "%xmm10", "%xmm11",\
"%xmm12", "%xmm13", "%xmm14", "%xmm15"
/* Include vzeroupper for non-AVX builds */
#ifndef __AVX__
#define IDCT_AVX_ASM(_IN0) \
__asm__( \
IDCT_AVX_BODY \
"vzeroupper \n" \
IDCT_AVX_OIC(_IN0) \
);
#else /* __AVX__ */
#define IDCT_AVX_ASM(_IN0) \
__asm__( \
IDCT_AVX_BODY \
IDCT_AVX_OIC(_IN0) \
);
#endif /* __AVX__ */
template <int zeroedRows>
void
dctInverse8x8_avx (float *data)
{
#if defined IMF_HAVE_GCC_INLINEASM_64
/* The column-major version of M1, followed by the
* column-major version of M2:
*
* [ a c a f ] [ b d e g ]
* M1 = [ a f -a -c ] M2 = [ d -g -b -e ]
* [ a -f -a c ] [ e -b g d ]
* [ a -c a -f ] [ g -e d -b ]
*/
const float sAvxCoef[32] __attribute__((aligned(32))) = {
3.535536e-01, 3.535536e-01, 3.535536e-01, 3.535536e-01, /* a a a a */
4.619398e-01, 1.913422e-01, -1.913422e-01, -4.619398e-01, /* c f -f -c */
3.535536e-01, -3.535536e-01, -3.535536e-01, 3.535536e-01, /* a -a -a a */
1.913422e-01, -4.619398e-01, 4.619398e-01, -1.913422e-01, /* f -c c -f */
4.903927e-01, 4.157349e-01, 2.777855e-01, 9.754573e-02, /* b d e g */
4.157349e-01, -9.754573e-02, -4.903927e-01, -2.777855e-01, /* d -g -b -e */
2.777855e-01, -4.903927e-01, 9.754573e-02, 4.157349e-01, /* e -b g d */
9.754573e-02, -2.777855e-01, 4.157349e-01, -4.903927e-01 /* g -e d -b */
};
#define ROW0(_X) _X
#define ROW1(_X) _X
#define ROW2(_X) _X
#define ROW3(_X) _X
#define ROW4(_X) _X
#define ROW5(_X) _X
#define ROW6(_X) _X
#define ROW7(_X) _X
if (zeroedRows == 0) {
IDCT_AVX_ASM(data)
} else if (zeroedRows == 1) {
#undef ROW7
#define ROW7(_X)
IDCT_AVX_ASM(data)
} else if (zeroedRows == 2) {
#undef ROW6
#define ROW6(_X)
IDCT_AVX_ASM(data)
} else if (zeroedRows == 3) {
#undef ROW5
#define ROW5(_X)
IDCT_AVX_ASM(data)
} else if (zeroedRows == 4) {
#undef ROW4
#define ROW4(_X)
IDCT_AVX_ASM(data)
} else if (zeroedRows == 5) {
#undef ROW3
#define ROW3(_X)
IDCT_AVX_ASM(data)
} else if (zeroedRows == 6) {
#undef ROW2
#define ROW2(_X)
IDCT_AVX_ASM(data)
} else if (zeroedRows == 7) {
__asm__(
/* ==============================================
* Row 1D DCT
* ----------------------------------------------
*/
IDCT_AVX_SETUP_2_ROWS(0, 4, 14, 15, 0, 16, 32, 48)
"vbroadcastf128 (%1), %%ymm8 \n"
"vbroadcastf128 16(%1), %%ymm9 \n"
"vbroadcastf128 32(%1), %%ymm10 \n"
"vbroadcastf128 48(%1), %%ymm11 \n"
/* Stash a vector of [a a a a | a a a a] away in ymm2 */
"vinsertf128 $1, %%xmm8, %%ymm8, %%ymm2 \n"
IDCT_AVX_MMULT_ROWS(%%ymm0)
"vbroadcastf128 64(%1), %%ymm8 \n"
"vbroadcastf128 80(%1), %%ymm9 \n"
"vbroadcastf128 96(%1), %%ymm10 \n"
"vbroadcastf128 112(%1), %%ymm11 \n"
IDCT_AVX_MMULT_ROWS(%%ymm4)
IDCT_AVX_EO_TO_ROW_HALVES(%%ymm0, %%ymm4, %%ymm0, %%ymm12)
"vperm2f128 $0x02, %%ymm0, %%ymm12, %%ymm0 \n"
/* ==============================================
* Column 1D DCT
* ----------------------------------------------
*/
/* DC only, so multiple by a and we're done */
"vmulps %%ymm2, %%ymm0, %%ymm0 \n"
/* Copy out results */
"vmovaps %%ymm0, (%0) \n"
"vmovaps %%ymm0, 32(%0) \n"
"vmovaps %%ymm0, 64(%0) \n"
"vmovaps %%ymm0, 96(%0) \n"
"vmovaps %%ymm0, 128(%0) \n"
"vmovaps %%ymm0, 160(%0) \n"
"vmovaps %%ymm0, 192(%0) \n"
"vmovaps %%ymm0, 224(%0) \n"
#ifndef __AVX__
"vzeroupper \n"
#endif /* __AVX__ */
IDCT_AVX_OIC(data)
);
} else {
assert(false); // Invalid template instance parameter
}
#else /* IMF_HAVE_GCC_INLINEASM_64 */
dctInverse8x8_scalar<zeroedRows>(data);
#endif /* IMF_HAVE_GCC_INLINEASM_64 */
}
//
// Full 8x8 Forward DCT:
//
// Base forward 8x8 DCT implementation. Works on the data in-place
//
// The implementation describedin Pennebaker + Mitchell,
// section 4.3.2, and illustrated in figure 4-7
//
// The basic idea is that the 1D DCT math reduces to:
//
// 2*out_0 = c_4 [(s_07 + s_34) + (s_12 + s_56)]
// 2*out_4 = c_4 [(s_07 + s_34) - (s_12 + s_56)]
//
// {2*out_2, 2*out_6} = rot_6 ((d_12 - d_56), (s_07 - s_34))
//
// {2*out_3, 2*out_5} = rot_-3 (d_07 - c_4 (s_12 - s_56),
// d_34 - c_4 (d_12 + d_56))
//
// {2*out_1, 2*out_7} = rot_-1 (d_07 + c_4 (s_12 - s_56),
// -d_34 - c_4 (d_12 + d_56))
//
// where:
//
// c_i = cos(i*pi/16)
// s_i = sin(i*pi/16)
//
// s_ij = in_i + in_j
// d_ij = in_i - in_j
//
// rot_i(x, y) = {c_i*x + s_i*y, -s_i*x + c_i*y}
//
// We'll run the DCT in two passes. First, run the 1D DCT on
// the rows, in-place. Then, run over the columns in-place,
// and be done with it.
//
#ifndef IMF_HAVE_SSE2
//
// Default implementation
//
void
dctForward8x8 (float *data)
{
float A0, A1, A2, A3, A4, A5, A6, A7;
float K0, K1, rot_x, rot_y;
float *srcPtr = data;
float *dstPtr = data;
const float c1 = cosf (3.14159f * 1.0f / 16.0f);
const float c2 = cosf (3.14159f * 2.0f / 16.0f);
const float c3 = cosf (3.14159f * 3.0f / 16.0f);
const float c4 = cosf (3.14159f * 4.0f / 16.0f);
const float c5 = cosf (3.14159f * 5.0f / 16.0f);
const float c6 = cosf (3.14159f * 6.0f / 16.0f);
const float c7 = cosf (3.14159f * 7.0f / 16.0f);
const float c1Half = .5f * c1;
const float c2Half = .5f * c2;
const float c3Half = .5f * c3;
const float c5Half = .5f * c5;
const float c6Half = .5f * c6;
const float c7Half = .5f * c7;
//
// First pass - do a 1D DCT over the rows and write the
// results back in place
//
for (int row=0; row<8; ++row)
{
float *srcRowPtr = srcPtr + 8 * row;
float *dstRowPtr = dstPtr + 8 * row;
A0 = srcRowPtr[0] + srcRowPtr[7];
A1 = srcRowPtr[1] + srcRowPtr[2];
A2 = srcRowPtr[1] - srcRowPtr[2];
A3 = srcRowPtr[3] + srcRowPtr[4];
A4 = srcRowPtr[3] - srcRowPtr[4];
A5 = srcRowPtr[5] + srcRowPtr[6];
A6 = srcRowPtr[5] - srcRowPtr[6];
A7 = srcRowPtr[0] - srcRowPtr[7];
K0 = c4 * (A0 + A3);
K1 = c4 * (A1 + A5);
dstRowPtr[0] = .5f * (K0 + K1);
dstRowPtr[4] = .5f * (K0 - K1);
//
// (2*dst2, 2*dst6) = rot 6 (d12 - d56, s07 - s34)
//
rot_x = A2 - A6;
rot_y = A0 - A3;
dstRowPtr[2] = c6Half * rot_x + c2Half * rot_y;
dstRowPtr[6] = c6Half * rot_y - c2Half * rot_x;
//
// K0, K1 are active until after dst[1],dst[7]
// as well as dst[3], dst[5] are computed.
//
K0 = c4 * (A1 - A5);
K1 = -1 * c4 * (A2 + A6);
//
// Two ways to do a rotation:
//
// rot i (x, y) =
// X = c_i*x + s_i*y
// Y = -s_i*x + c_i*y
//
// OR
//
// X = c_i*(x+y) + (s_i-c_i)*y
// Y = c_i*y - (s_i+c_i)*x
//
// the first case has 4 multiplies, but fewer constants,
// while the 2nd case has fewer multiplies but takes more space.
//
// (2*dst3, 2*dst5) = rot -3 ( d07 - K0, d34 + K1 )
//
rot_x = A7 - K0;
rot_y = A4 + K1;
dstRowPtr[3] = c3Half * rot_x - c5Half * rot_y;
dstRowPtr[5] = c5Half * rot_x + c3Half * rot_y;
//
// (2*dst1, 2*dst7) = rot -1 ( d07 + K0, K1 - d34 )
//
rot_x = A7 + K0;
rot_y = K1 - A4;
//
// A: 4, 7 are inactive. All A's are inactive
//
dstRowPtr[1] = c1Half * rot_x - c7Half * rot_y;
dstRowPtr[7] = c7Half * rot_x + c1Half * rot_y;
}
//
// Second pass - do the same, but on the columns
//
for (int column = 0; column < 8; ++column)
{
A0 = srcPtr[ column] + srcPtr[56 + column];
A7 = srcPtr[ column] - srcPtr[56 + column];
A1 = srcPtr[ 8 + column] + srcPtr[16 + column];
A2 = srcPtr[ 8 + column] - srcPtr[16 + column];
A3 = srcPtr[24 + column] + srcPtr[32 + column];
A4 = srcPtr[24 + column] - srcPtr[32 + column];
A5 = srcPtr[40 + column] + srcPtr[48 + column];
A6 = srcPtr[40 + column] - srcPtr[48 + column];
K0 = c4 * (A0 + A3);
K1 = c4 * (A1 + A5);
dstPtr[ column] = .5f * (K0 + K1);
dstPtr[32+column] = .5f * (K0 - K1);
//
// (2*dst2, 2*dst6) = rot 6 ( d12 - d56, s07 - s34 )
//
rot_x = A2 - A6;
rot_y = A0 - A3;
dstPtr[16+column] = .5f * (c6 * rot_x + c2 * rot_y);
dstPtr[48+column] = .5f * (c6 * rot_y - c2 * rot_x);
//
// K0, K1 are active until after dst[1],dst[7]
// as well as dst[3], dst[5] are computed.
//
K0 = c4 * (A1 - A5);
K1 = -1 * c4 * (A2 + A6);
//
// (2*dst3, 2*dst5) = rot -3 ( d07 - K0, d34 + K1 )
//
rot_x = A7 - K0;
rot_y = A4 + K1;
dstPtr[24+column] = .5f * (c3 * rot_x - c5 * rot_y);
dstPtr[40+column] = .5f * (c5 * rot_x + c3 * rot_y);
//
// (2*dst1, 2*dst7) = rot -1 ( d07 + K0, K1 - d34 )
//
rot_x = A7 + K0;
rot_y = K1 - A4;
dstPtr[ 8+column] = .5f * (c1 * rot_x - c7 * rot_y);
dstPtr[56+column] = .5f * (c7 * rot_x + c1 * rot_y);
}
}
#else /* IMF_HAVE_SSE2 */
//
// SSE2 implementation
//
// Here, we're always doing a column-wise operation
// plus transposes. This might be faster to do differently
// between rows-wise and column-wise
//
void
dctForward8x8 (float *data)
{
__m128 *srcVec = (__m128 *)data;
__m128 a0Vec, a1Vec, a2Vec, a3Vec, a4Vec, a5Vec, a6Vec, a7Vec;
__m128 k0Vec, k1Vec, rotXVec, rotYVec;
__m128 transTmp[4], transTmp2[4];
__m128 c4Vec = { .70710678f, .70710678f, .70710678f, .70710678f};
__m128 c4NegVec = {-.70710678f, -.70710678f, -.70710678f, -.70710678f};
__m128 c1HalfVec = {.490392640f, .490392640f, .490392640f, .490392640f};
__m128 c2HalfVec = {.461939770f, .461939770f, .461939770f, .461939770f};
__m128 c3HalfVec = {.415734810f, .415734810f, .415734810f, .415734810f};
__m128 c5HalfVec = {.277785120f, .277785120f, .277785120f, .277785120f};
__m128 c6HalfVec = {.191341720f, .191341720f, .191341720f, .191341720f};
__m128 c7HalfVec = {.097545161f, .097545161f, .097545161f, .097545161f};
__m128 halfVec = {.5f, .5f, .5f, .5f};
for (int iter = 0; iter < 2; ++iter)
{
//
// Operate on 4 columns at a time. The
// offsets into our row-major array are:
// 0: 0 1
// 1: 2 3
// 2: 4 5
// 3: 6 7
// 4: 8 9
// 5: 10 11
// 6: 12 13
// 7: 14 15
//
for (int pass=0; pass<2; ++pass)
{
a0Vec = _mm_add_ps (srcVec[ 0 + pass], srcVec[14 + pass]);
a1Vec = _mm_add_ps (srcVec[ 2 + pass], srcVec[ 4 + pass]);
a3Vec = _mm_add_ps (srcVec[ 6 + pass], srcVec[ 8 + pass]);
a5Vec = _mm_add_ps (srcVec[10 + pass], srcVec[12 + pass]);
a7Vec = _mm_sub_ps (srcVec[ 0 + pass], srcVec[14 + pass]);
a2Vec = _mm_sub_ps (srcVec[ 2 + pass], srcVec[ 4 + pass]);
a4Vec = _mm_sub_ps (srcVec[ 6 + pass], srcVec[ 8 + pass]);
a6Vec = _mm_sub_ps (srcVec[10 + pass], srcVec[12 + pass]);
//
// First stage; Compute out_0 and out_4
//
k0Vec = _mm_add_ps (a0Vec, a3Vec);
k1Vec = _mm_add_ps (a1Vec, a5Vec);
k0Vec = _mm_mul_ps (c4Vec, k0Vec);
k1Vec = _mm_mul_ps (c4Vec, k1Vec);
srcVec[0 + pass] = _mm_add_ps (k0Vec, k1Vec);
srcVec[8 + pass] = _mm_sub_ps (k0Vec, k1Vec);
srcVec[0 + pass] = _mm_mul_ps (srcVec[0 + pass], halfVec );
srcVec[8 + pass] = _mm_mul_ps (srcVec[8 + pass], halfVec );
//
// Second stage; Compute out_2 and out_6
//
k0Vec = _mm_sub_ps (a2Vec, a6Vec);
k1Vec = _mm_sub_ps (a0Vec, a3Vec);
srcVec[ 4 + pass] = _mm_add_ps (_mm_mul_ps (c6HalfVec, k0Vec),
_mm_mul_ps (c2HalfVec, k1Vec));
srcVec[12 + pass] = _mm_sub_ps (_mm_mul_ps (c6HalfVec, k1Vec),
_mm_mul_ps (c2HalfVec, k0Vec));
//
// Precompute K0 and K1 for the remaining stages
//
k0Vec = _mm_mul_ps (_mm_sub_ps (a1Vec, a5Vec), c4Vec);
k1Vec = _mm_mul_ps (_mm_add_ps (a2Vec, a6Vec), c4NegVec);
//
// Third Stage, compute out_3 and out_5
//
rotXVec = _mm_sub_ps (a7Vec, k0Vec);
rotYVec = _mm_add_ps (a4Vec, k1Vec);
srcVec[ 6 + pass] = _mm_sub_ps (_mm_mul_ps (c3HalfVec, rotXVec),
_mm_mul_ps (c5HalfVec, rotYVec));
srcVec[10 + pass] = _mm_add_ps (_mm_mul_ps (c5HalfVec, rotXVec),
_mm_mul_ps (c3HalfVec, rotYVec));
//
// Fourth Stage, compute out_1 and out_7
//
rotXVec = _mm_add_ps (a7Vec, k0Vec);
rotYVec = _mm_sub_ps (k1Vec, a4Vec);
srcVec[ 2 + pass] = _mm_sub_ps (_mm_mul_ps (c1HalfVec, rotXVec),
_mm_mul_ps (c7HalfVec, rotYVec));
srcVec[14 + pass] = _mm_add_ps (_mm_mul_ps (c7HalfVec, rotXVec),
_mm_mul_ps (c1HalfVec, rotYVec));
}
//
// Transpose the matrix, in 4x4 blocks. So, if we have our
// 8x8 matrix divied into 4x4 blocks:
//
// M0 | M1 M0t | M2t
// ----+--- --> -----+------
// M2 | M3 M1t | M3t
//
//
// M0t, done in place, the first half.
//
transTmp[0] = _mm_shuffle_ps (srcVec[0], srcVec[2], 0x44);
transTmp[1] = _mm_shuffle_ps (srcVec[4], srcVec[6], 0x44);
transTmp[3] = _mm_shuffle_ps (srcVec[4], srcVec[6], 0xEE);
transTmp[2] = _mm_shuffle_ps (srcVec[0], srcVec[2], 0xEE);
//
// M3t, also done in place, the first half.
//
transTmp2[0] = _mm_shuffle_ps (srcVec[ 9], srcVec[11], 0x44);
transTmp2[1] = _mm_shuffle_ps (srcVec[13], srcVec[15], 0x44);
transTmp2[2] = _mm_shuffle_ps (srcVec[ 9], srcVec[11], 0xEE);
transTmp2[3] = _mm_shuffle_ps (srcVec[13], srcVec[15], 0xEE);
//
// M0t, the second half.
//
srcVec[0] = _mm_shuffle_ps (transTmp[0], transTmp[1], 0x88);
srcVec[4] = _mm_shuffle_ps (transTmp[2], transTmp[3], 0x88);
srcVec[2] = _mm_shuffle_ps (transTmp[0], transTmp[1], 0xDD);
srcVec[6] = _mm_shuffle_ps (transTmp[2], transTmp[3], 0xDD);
//
// M3t, the second half.
//
srcVec[ 9] = _mm_shuffle_ps (transTmp2[0], transTmp2[1], 0x88);
srcVec[13] = _mm_shuffle_ps (transTmp2[2], transTmp2[3], 0x88);
srcVec[11] = _mm_shuffle_ps (transTmp2[0], transTmp2[1], 0xDD);
srcVec[15] = _mm_shuffle_ps (transTmp2[2], transTmp2[3], 0xDD);
//
// M1 and M2 need to be done at the same time, because we're
// swapping.
//
// First, the first half of M1t
//
transTmp[0] = _mm_shuffle_ps (srcVec[1], srcVec[3], 0x44);
transTmp[1] = _mm_shuffle_ps (srcVec[5], srcVec[7], 0x44);
transTmp[2] = _mm_shuffle_ps (srcVec[1], srcVec[3], 0xEE);
transTmp[3] = _mm_shuffle_ps (srcVec[5], srcVec[7], 0xEE);
//
// And the first half of M2t
//
transTmp2[0] = _mm_shuffle_ps (srcVec[ 8], srcVec[10], 0x44);
transTmp2[1] = _mm_shuffle_ps (srcVec[12], srcVec[14], 0x44);
transTmp2[2] = _mm_shuffle_ps (srcVec[ 8], srcVec[10], 0xEE);
transTmp2[3] = _mm_shuffle_ps (srcVec[12], srcVec[14], 0xEE);
//
// Second half of M1t
//
srcVec[ 8] = _mm_shuffle_ps (transTmp[0], transTmp[1], 0x88);
srcVec[12] = _mm_shuffle_ps (transTmp[2], transTmp[3], 0x88);
srcVec[10] = _mm_shuffle_ps (transTmp[0], transTmp[1], 0xDD);
srcVec[14] = _mm_shuffle_ps (transTmp[2], transTmp[3], 0xDD);
//
// Second half of M2
//
srcVec[1] = _mm_shuffle_ps (transTmp2[0], transTmp2[1], 0x88);
srcVec[5] = _mm_shuffle_ps (transTmp2[2], transTmp2[3], 0x88);
srcVec[3] = _mm_shuffle_ps (transTmp2[0], transTmp2[1], 0xDD);
srcVec[7] = _mm_shuffle_ps (transTmp2[2], transTmp2[3], 0xDD);
}
}
#endif /* IMF_HAVE_SSE2 */
} // anonymous namespace
OPENEXR_IMF_INTERNAL_NAMESPACE_HEADER_EXIT
#endif