/*
* Copyright 2013 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include <emmintrin.h>
#include "SkBitmap.h"
#include "SkBitmapFilter_opts_SSE2.h"
#include "SkBitmapProcState.h"
#include "SkColor.h"
#include "SkColorPriv.h"
#include "SkConvolver.h"
#include "SkShader.h"
#include "SkUnPreMultiply.h"
#if 0
static inline void print128i(__m128i value) {
int *v = (int*) &value;
printf("% .11d % .11d % .11d % .11d\n", v[0], v[1], v[2], v[3]);
}
static inline void print128i_16(__m128i value) {
short *v = (short*) &value;
printf("% .5d % .5d % .5d % .5d % .5d % .5d % .5d % .5d\n", v[0], v[1], v[2], v[3], v[4], v[5], v[6], v[7]);
}
static inline void print128i_8(__m128i value) {
unsigned char *v = (unsigned char*) &value;
printf("%.3u %.3u %.3u %.3u %.3u %.3u %.3u %.3u %.3u %.3u %.3u %.3u %.3u %.3u %.3u %.3u\n",
v[0], v[1], v[2], v[3], v[4], v[5], v[6], v[7],
v[8], v[9], v[10], v[11], v[12], v[13], v[14], v[15]
);
}
static inline void print128f(__m128 value) {
float *f = (float*) &value;
printf("%3.4f %3.4f %3.4f %3.4f\n", f[0], f[1], f[2], f[3]);
}
#endif
// Convolves horizontally along a single row. The row data is given in
// |src_data| and continues for the num_values() of the filter.
void convolveHorizontally_SSE2(const unsigned char* src_data,
const SkConvolutionFilter1D& filter,
unsigned char* out_row,
bool /*has_alpha*/) {
int num_values = filter.numValues();
int filter_offset, filter_length;
__m128i zero = _mm_setzero_si128();
__m128i mask[4];
// |mask| will be used to decimate all extra filter coefficients that are
// loaded by SIMD when |filter_length| is not divisible by 4.
// mask[0] is not used in following algorithm.
mask[1] = _mm_set_epi16(0, 0, 0, 0, 0, 0, 0, -1);
mask[2] = _mm_set_epi16(0, 0, 0, 0, 0, 0, -1, -1);
mask[3] = _mm_set_epi16(0, 0, 0, 0, 0, -1, -1, -1);
// Output one pixel each iteration, calculating all channels (RGBA) together.
for (int out_x = 0; out_x < num_values; out_x++) {
const SkConvolutionFilter1D::ConvolutionFixed* filter_values =
filter.FilterForValue(out_x, &filter_offset, &filter_length);
__m128i accum = _mm_setzero_si128();
// Compute the first pixel in this row that the filter affects. It will
// touch |filter_length| pixels (4 bytes each) after this.
const __m128i* row_to_filter =
reinterpret_cast<const __m128i*>(&src_data[filter_offset << 2]);
// We will load and accumulate with four coefficients per iteration.
for (int filter_x = 0; filter_x < filter_length >> 2; filter_x++) {
// Load 4 coefficients => duplicate 1st and 2nd of them for all channels.
__m128i coeff, coeff16;
// [16] xx xx xx xx c3 c2 c1 c0
coeff = _mm_loadl_epi64(reinterpret_cast<const __m128i*>(filter_values));
// [16] xx xx xx xx c1 c1 c0 c0
coeff16 = _mm_shufflelo_epi16(coeff, _MM_SHUFFLE(1, 1, 0, 0));
// [16] c1 c1 c1 c1 c0 c0 c0 c0
coeff16 = _mm_unpacklo_epi16(coeff16, coeff16);
// Load four pixels => unpack the first two pixels to 16 bits =>
// multiply with coefficients => accumulate the convolution result.
// [8] a3 b3 g3 r3 a2 b2 g2 r2 a1 b1 g1 r1 a0 b0 g0 r0
__m128i src8 = _mm_loadu_si128(row_to_filter);
// [16] a1 b1 g1 r1 a0 b0 g0 r0
__m128i src16 = _mm_unpacklo_epi8(src8, zero);
__m128i mul_hi = _mm_mulhi_epi16(src16, coeff16);
__m128i mul_lo = _mm_mullo_epi16(src16, coeff16);
// [32] a0*c0 b0*c0 g0*c0 r0*c0
__m128i t = _mm_unpacklo_epi16(mul_lo, mul_hi);
accum = _mm_add_epi32(accum, t);
// [32] a1*c1 b1*c1 g1*c1 r1*c1
t = _mm_unpackhi_epi16(mul_lo, mul_hi);
accum = _mm_add_epi32(accum, t);
// Duplicate 3rd and 4th coefficients for all channels =>
// unpack the 3rd and 4th pixels to 16 bits => multiply with coefficients
// => accumulate the convolution results.
// [16] xx xx xx xx c3 c3 c2 c2
coeff16 = _mm_shufflelo_epi16(coeff, _MM_SHUFFLE(3, 3, 2, 2));
// [16] c3 c3 c3 c3 c2 c2 c2 c2
coeff16 = _mm_unpacklo_epi16(coeff16, coeff16);
// [16] a3 g3 b3 r3 a2 g2 b2 r2
src16 = _mm_unpackhi_epi8(src8, zero);
mul_hi = _mm_mulhi_epi16(src16, coeff16);
mul_lo = _mm_mullo_epi16(src16, coeff16);
// [32] a2*c2 b2*c2 g2*c2 r2*c2
t = _mm_unpacklo_epi16(mul_lo, mul_hi);
accum = _mm_add_epi32(accum, t);
// [32] a3*c3 b3*c3 g3*c3 r3*c3
t = _mm_unpackhi_epi16(mul_lo, mul_hi);
accum = _mm_add_epi32(accum, t);
// Advance the pixel and coefficients pointers.
row_to_filter += 1;
filter_values += 4;
}
// When |filter_length| is not divisible by 4, we need to decimate some of
// the filter coefficient that was loaded incorrectly to zero; Other than
// that the algorithm is same with above, exceot that the 4th pixel will be
// always absent.
int r = filter_length&3;
if (r) {
// Note: filter_values must be padded to align_up(filter_offset, 8).
__m128i coeff, coeff16;
coeff = _mm_loadl_epi64(reinterpret_cast<const __m128i*>(filter_values));
// Mask out extra filter taps.
coeff = _mm_and_si128(coeff, mask[r]);
coeff16 = _mm_shufflelo_epi16(coeff, _MM_SHUFFLE(1, 1, 0, 0));
coeff16 = _mm_unpacklo_epi16(coeff16, coeff16);
// Note: line buffer must be padded to align_up(filter_offset, 16).
// We resolve this by use C-version for the last horizontal line.
__m128i src8 = _mm_loadu_si128(row_to_filter);
__m128i src16 = _mm_unpacklo_epi8(src8, zero);
__m128i mul_hi = _mm_mulhi_epi16(src16, coeff16);
__m128i mul_lo = _mm_mullo_epi16(src16, coeff16);
__m128i t = _mm_unpacklo_epi16(mul_lo, mul_hi);
accum = _mm_add_epi32(accum, t);
t = _mm_unpackhi_epi16(mul_lo, mul_hi);
accum = _mm_add_epi32(accum, t);
src16 = _mm_unpackhi_epi8(src8, zero);
coeff16 = _mm_shufflelo_epi16(coeff, _MM_SHUFFLE(3, 3, 2, 2));
coeff16 = _mm_unpacklo_epi16(coeff16, coeff16);
mul_hi = _mm_mulhi_epi16(src16, coeff16);
mul_lo = _mm_mullo_epi16(src16, coeff16);
t = _mm_unpacklo_epi16(mul_lo, mul_hi);
accum = _mm_add_epi32(accum, t);
}
// Shift right for fixed point implementation.
accum = _mm_srai_epi32(accum, SkConvolutionFilter1D::kShiftBits);
// Packing 32 bits |accum| to 16 bits per channel (signed saturation).
accum = _mm_packs_epi32(accum, zero);
// Packing 16 bits |accum| to 8 bits per channel (unsigned saturation).
accum = _mm_packus_epi16(accum, zero);
// Store the pixel value of 32 bits.
*(reinterpret_cast<int*>(out_row)) = _mm_cvtsi128_si32(accum);
out_row += 4;
}
}
// Convolves horizontally along four rows. The row data is given in
// |src_data| and continues for the num_values() of the filter.
// The algorithm is almost same as |ConvolveHorizontally_SSE2|. Please
// refer to that function for detailed comments.
void convolve4RowsHorizontally_SSE2(const unsigned char* src_data[4],
const SkConvolutionFilter1D& filter,
unsigned char* out_row[4]) {
int num_values = filter.numValues();
int filter_offset, filter_length;
__m128i zero = _mm_setzero_si128();
__m128i mask[4];
// |mask| will be used to decimate all extra filter coefficients that are
// loaded by SIMD when |filter_length| is not divisible by 4.
// mask[0] is not used in following algorithm.
mask[1] = _mm_set_epi16(0, 0, 0, 0, 0, 0, 0, -1);
mask[2] = _mm_set_epi16(0, 0, 0, 0, 0, 0, -1, -1);
mask[3] = _mm_set_epi16(0, 0, 0, 0, 0, -1, -1, -1);
// Output one pixel each iteration, calculating all channels (RGBA) together.
for (int out_x = 0; out_x < num_values; out_x++) {
const SkConvolutionFilter1D::ConvolutionFixed* filter_values =
filter.FilterForValue(out_x, &filter_offset, &filter_length);
// four pixels in a column per iteration.
__m128i accum0 = _mm_setzero_si128();
__m128i accum1 = _mm_setzero_si128();
__m128i accum2 = _mm_setzero_si128();
__m128i accum3 = _mm_setzero_si128();
int start = (filter_offset<<2);
// We will load and accumulate with four coefficients per iteration.
for (int filter_x = 0; filter_x < (filter_length >> 2); filter_x++) {
__m128i coeff, coeff16lo, coeff16hi;
// [16] xx xx xx xx c3 c2 c1 c0
coeff = _mm_loadl_epi64(reinterpret_cast<const __m128i*>(filter_values));
// [16] xx xx xx xx c1 c1 c0 c0
coeff16lo = _mm_shufflelo_epi16(coeff, _MM_SHUFFLE(1, 1, 0, 0));
// [16] c1 c1 c1 c1 c0 c0 c0 c0
coeff16lo = _mm_unpacklo_epi16(coeff16lo, coeff16lo);
// [16] xx xx xx xx c3 c3 c2 c2
coeff16hi = _mm_shufflelo_epi16(coeff, _MM_SHUFFLE(3, 3, 2, 2));
// [16] c3 c3 c3 c3 c2 c2 c2 c2
coeff16hi = _mm_unpacklo_epi16(coeff16hi, coeff16hi);
__m128i src8, src16, mul_hi, mul_lo, t;
#define ITERATION(src, accum) \
src8 = _mm_loadu_si128(reinterpret_cast<const __m128i*>(src)); \
src16 = _mm_unpacklo_epi8(src8, zero); \
mul_hi = _mm_mulhi_epi16(src16, coeff16lo); \
mul_lo = _mm_mullo_epi16(src16, coeff16lo); \
t = _mm_unpacklo_epi16(mul_lo, mul_hi); \
accum = _mm_add_epi32(accum, t); \
t = _mm_unpackhi_epi16(mul_lo, mul_hi); \
accum = _mm_add_epi32(accum, t); \
src16 = _mm_unpackhi_epi8(src8, zero); \
mul_hi = _mm_mulhi_epi16(src16, coeff16hi); \
mul_lo = _mm_mullo_epi16(src16, coeff16hi); \
t = _mm_unpacklo_epi16(mul_lo, mul_hi); \
accum = _mm_add_epi32(accum, t); \
t = _mm_unpackhi_epi16(mul_lo, mul_hi); \
accum = _mm_add_epi32(accum, t)
ITERATION(src_data[0] + start, accum0);
ITERATION(src_data[1] + start, accum1);
ITERATION(src_data[2] + start, accum2);
ITERATION(src_data[3] + start, accum3);
start += 16;
filter_values += 4;
}
int r = filter_length & 3;
if (r) {
// Note: filter_values must be padded to align_up(filter_offset, 8);
__m128i coeff;
coeff = _mm_loadl_epi64(reinterpret_cast<const __m128i*>(filter_values));
// Mask out extra filter taps.
coeff = _mm_and_si128(coeff, mask[r]);
__m128i coeff16lo = _mm_shufflelo_epi16(coeff, _MM_SHUFFLE(1, 1, 0, 0));
/* c1 c1 c1 c1 c0 c0 c0 c0 */
coeff16lo = _mm_unpacklo_epi16(coeff16lo, coeff16lo);
__m128i coeff16hi = _mm_shufflelo_epi16(coeff, _MM_SHUFFLE(3, 3, 2, 2));
coeff16hi = _mm_unpacklo_epi16(coeff16hi, coeff16hi);
__m128i src8, src16, mul_hi, mul_lo, t;
ITERATION(src_data[0] + start, accum0);
ITERATION(src_data[1] + start, accum1);
ITERATION(src_data[2] + start, accum2);
ITERATION(src_data[3] + start, accum3);
}
accum0 = _mm_srai_epi32(accum0, SkConvolutionFilter1D::kShiftBits);
accum0 = _mm_packs_epi32(accum0, zero);
accum0 = _mm_packus_epi16(accum0, zero);
accum1 = _mm_srai_epi32(accum1, SkConvolutionFilter1D::kShiftBits);
accum1 = _mm_packs_epi32(accum1, zero);
accum1 = _mm_packus_epi16(accum1, zero);
accum2 = _mm_srai_epi32(accum2, SkConvolutionFilter1D::kShiftBits);
accum2 = _mm_packs_epi32(accum2, zero);
accum2 = _mm_packus_epi16(accum2, zero);
accum3 = _mm_srai_epi32(accum3, SkConvolutionFilter1D::kShiftBits);
accum3 = _mm_packs_epi32(accum3, zero);
accum3 = _mm_packus_epi16(accum3, zero);
*(reinterpret_cast<int*>(out_row[0])) = _mm_cvtsi128_si32(accum0);
*(reinterpret_cast<int*>(out_row[1])) = _mm_cvtsi128_si32(accum1);
*(reinterpret_cast<int*>(out_row[2])) = _mm_cvtsi128_si32(accum2);
*(reinterpret_cast<int*>(out_row[3])) = _mm_cvtsi128_si32(accum3);
out_row[0] += 4;
out_row[1] += 4;
out_row[2] += 4;
out_row[3] += 4;
}
}
// Does vertical convolution to produce one output row. The filter values and
// length are given in the first two parameters. These are applied to each
// of the rows pointed to in the |source_data_rows| array, with each row
// being |pixel_width| wide.
//
// The output must have room for |pixel_width * 4| bytes.
template<bool has_alpha>
void convolveVertically_SSE2(const SkConvolutionFilter1D::ConvolutionFixed* filter_values,
int filter_length,
unsigned char* const* source_data_rows,
int pixel_width,
unsigned char* out_row) {
int width = pixel_width & ~3;
__m128i zero = _mm_setzero_si128();
__m128i accum0, accum1, accum2, accum3, coeff16;
const __m128i* src;
// Output four pixels per iteration (16 bytes).
for (int out_x = 0; out_x < width; out_x += 4) {
// Accumulated result for each pixel. 32 bits per RGBA channel.
accum0 = _mm_setzero_si128();
accum1 = _mm_setzero_si128();
accum2 = _mm_setzero_si128();
accum3 = _mm_setzero_si128();
// Convolve with one filter coefficient per iteration.
for (int filter_y = 0; filter_y < filter_length; filter_y++) {
// Duplicate the filter coefficient 8 times.
// [16] cj cj cj cj cj cj cj cj
coeff16 = _mm_set1_epi16(filter_values[filter_y]);
// Load four pixels (16 bytes) together.
// [8] a3 b3 g3 r3 a2 b2 g2 r2 a1 b1 g1 r1 a0 b0 g0 r0
src = reinterpret_cast<const __m128i*>(
&source_data_rows[filter_y][out_x << 2]);
__m128i src8 = _mm_loadu_si128(src);
// Unpack 1st and 2nd pixels from 8 bits to 16 bits for each channels =>
// multiply with current coefficient => accumulate the result.
// [16] a1 b1 g1 r1 a0 b0 g0 r0
__m128i src16 = _mm_unpacklo_epi8(src8, zero);
__m128i mul_hi = _mm_mulhi_epi16(src16, coeff16);
__m128i mul_lo = _mm_mullo_epi16(src16, coeff16);
// [32] a0 b0 g0 r0
__m128i t = _mm_unpacklo_epi16(mul_lo, mul_hi);
accum0 = _mm_add_epi32(accum0, t);
// [32] a1 b1 g1 r1
t = _mm_unpackhi_epi16(mul_lo, mul_hi);
accum1 = _mm_add_epi32(accum1, t);
// Unpack 3rd and 4th pixels from 8 bits to 16 bits for each channels =>
// multiply with current coefficient => accumulate the result.
// [16] a3 b3 g3 r3 a2 b2 g2 r2
src16 = _mm_unpackhi_epi8(src8, zero);
mul_hi = _mm_mulhi_epi16(src16, coeff16);
mul_lo = _mm_mullo_epi16(src16, coeff16);
// [32] a2 b2 g2 r2
t = _mm_unpacklo_epi16(mul_lo, mul_hi);
accum2 = _mm_add_epi32(accum2, t);
// [32] a3 b3 g3 r3
t = _mm_unpackhi_epi16(mul_lo, mul_hi);
accum3 = _mm_add_epi32(accum3, t);
}
// Shift right for fixed point implementation.
accum0 = _mm_srai_epi32(accum0, SkConvolutionFilter1D::kShiftBits);
accum1 = _mm_srai_epi32(accum1, SkConvolutionFilter1D::kShiftBits);
accum2 = _mm_srai_epi32(accum2, SkConvolutionFilter1D::kShiftBits);
accum3 = _mm_srai_epi32(accum3, SkConvolutionFilter1D::kShiftBits);
// Packing 32 bits |accum| to 16 bits per channel (signed saturation).
// [16] a1 b1 g1 r1 a0 b0 g0 r0
accum0 = _mm_packs_epi32(accum0, accum1);
// [16] a3 b3 g3 r3 a2 b2 g2 r2
accum2 = _mm_packs_epi32(accum2, accum3);
// Packing 16 bits |accum| to 8 bits per channel (unsigned saturation).
// [8] a3 b3 g3 r3 a2 b2 g2 r2 a1 b1 g1 r1 a0 b0 g0 r0
accum0 = _mm_packus_epi16(accum0, accum2);
if (has_alpha) {
// Compute the max(ri, gi, bi) for each pixel.
// [8] xx a3 b3 g3 xx a2 b2 g2 xx a1 b1 g1 xx a0 b0 g0
__m128i a = _mm_srli_epi32(accum0, 8);
// [8] xx xx xx max3 xx xx xx max2 xx xx xx max1 xx xx xx max0
__m128i b = _mm_max_epu8(a, accum0); // Max of r and g.
// [8] xx xx a3 b3 xx xx a2 b2 xx xx a1 b1 xx xx a0 b0
a = _mm_srli_epi32(accum0, 16);
// [8] xx xx xx max3 xx xx xx max2 xx xx xx max1 xx xx xx max0
b = _mm_max_epu8(a, b); // Max of r and g and b.
// [8] max3 00 00 00 max2 00 00 00 max1 00 00 00 max0 00 00 00
b = _mm_slli_epi32(b, 24);
// Make sure the value of alpha channel is always larger than maximum
// value of color channels.
accum0 = _mm_max_epu8(b, accum0);
} else {
// Set value of alpha channels to 0xFF.
__m128i mask = _mm_set1_epi32(0xff000000);
accum0 = _mm_or_si128(accum0, mask);
}
// Store the convolution result (16 bytes) and advance the pixel pointers.
_mm_storeu_si128(reinterpret_cast<__m128i*>(out_row), accum0);
out_row += 16;
}
// When the width of the output is not divisible by 4, We need to save one
// pixel (4 bytes) each time. And also the fourth pixel is always absent.
if (pixel_width & 3) {
accum0 = _mm_setzero_si128();
accum1 = _mm_setzero_si128();
accum2 = _mm_setzero_si128();
for (int filter_y = 0; filter_y < filter_length; ++filter_y) {
coeff16 = _mm_set1_epi16(filter_values[filter_y]);
// [8] a3 b3 g3 r3 a2 b2 g2 r2 a1 b1 g1 r1 a0 b0 g0 r0
src = reinterpret_cast<const __m128i*>(
&source_data_rows[filter_y][width<<2]);
__m128i src8 = _mm_loadu_si128(src);
// [16] a1 b1 g1 r1 a0 b0 g0 r0
__m128i src16 = _mm_unpacklo_epi8(src8, zero);
__m128i mul_hi = _mm_mulhi_epi16(src16, coeff16);
__m128i mul_lo = _mm_mullo_epi16(src16, coeff16);
// [32] a0 b0 g0 r0
__m128i t = _mm_unpacklo_epi16(mul_lo, mul_hi);
accum0 = _mm_add_epi32(accum0, t);
// [32] a1 b1 g1 r1
t = _mm_unpackhi_epi16(mul_lo, mul_hi);
accum1 = _mm_add_epi32(accum1, t);
// [16] a3 b3 g3 r3 a2 b2 g2 r2
src16 = _mm_unpackhi_epi8(src8, zero);
mul_hi = _mm_mulhi_epi16(src16, coeff16);
mul_lo = _mm_mullo_epi16(src16, coeff16);
// [32] a2 b2 g2 r2
t = _mm_unpacklo_epi16(mul_lo, mul_hi);
accum2 = _mm_add_epi32(accum2, t);
}
accum0 = _mm_srai_epi32(accum0, SkConvolutionFilter1D::kShiftBits);
accum1 = _mm_srai_epi32(accum1, SkConvolutionFilter1D::kShiftBits);
accum2 = _mm_srai_epi32(accum2, SkConvolutionFilter1D::kShiftBits);
// [16] a1 b1 g1 r1 a0 b0 g0 r0
accum0 = _mm_packs_epi32(accum0, accum1);
// [16] a3 b3 g3 r3 a2 b2 g2 r2
accum2 = _mm_packs_epi32(accum2, zero);
// [8] a3 b3 g3 r3 a2 b2 g2 r2 a1 b1 g1 r1 a0 b0 g0 r0
accum0 = _mm_packus_epi16(accum0, accum2);
if (has_alpha) {
// [8] xx a3 b3 g3 xx a2 b2 g2 xx a1 b1 g1 xx a0 b0 g0
__m128i a = _mm_srli_epi32(accum0, 8);
// [8] xx xx xx max3 xx xx xx max2 xx xx xx max1 xx xx xx max0
__m128i b = _mm_max_epu8(a, accum0); // Max of r and g.
// [8] xx xx a3 b3 xx xx a2 b2 xx xx a1 b1 xx xx a0 b0
a = _mm_srli_epi32(accum0, 16);
// [8] xx xx xx max3 xx xx xx max2 xx xx xx max1 xx xx xx max0
b = _mm_max_epu8(a, b); // Max of r and g and b.
// [8] max3 00 00 00 max2 00 00 00 max1 00 00 00 max0 00 00 00
b = _mm_slli_epi32(b, 24);
accum0 = _mm_max_epu8(b, accum0);
} else {
__m128i mask = _mm_set1_epi32(0xff000000);
accum0 = _mm_or_si128(accum0, mask);
}
for (int out_x = width; out_x < pixel_width; out_x++) {
*(reinterpret_cast<int*>(out_row)) = _mm_cvtsi128_si32(accum0);
accum0 = _mm_srli_si128(accum0, 4);
out_row += 4;
}
}
}
void convolveVertically_SSE2(const SkConvolutionFilter1D::ConvolutionFixed* filter_values,
int filter_length,
unsigned char* const* source_data_rows,
int pixel_width,
unsigned char* out_row,
bool has_alpha) {
if (has_alpha) {
convolveVertically_SSE2<true>(filter_values,
filter_length,
source_data_rows,
pixel_width,
out_row);
} else {
convolveVertically_SSE2<false>(filter_values,
filter_length,
source_data_rows,
pixel_width,
out_row);
}
}
void applySIMDPadding_SSE2(SkConvolutionFilter1D *filter) {
// Padding |paddingCount| of more dummy coefficients after the coefficients
// of last filter to prevent SIMD instructions which load 8 or 16 bytes
// together to access invalid memory areas. We are not trying to align the
// coefficients right now due to the opaqueness of <vector> implementation.
// This has to be done after all |AddFilter| calls.
for (int i = 0; i < 8; ++i) {
filter->addFilterValue(static_cast<SkConvolutionFilter1D::ConvolutionFixed>(0));
}
}