namespace SK_OPTS_NS {
-#if SK_CPU_SSE_LEVEL >= SK_CPU_SSE_LEVEL_AVX2
-
- static SK_ALWAYS_INLINE
- void compute_coefficient_row(SkConvolutionFilter1D::ConvolutionFixed filterValue, const unsigned char* sourceDataRows,
- __m256i* accum01, __m256i* accum23, __m256i* accum45, __m256i* accum67) {
- __m256i coefs = _mm256_set1_epi16(filterValue);
- __m256i pixels = _mm256_loadu_si256(reinterpret_cast<const __m256i *>(sourceDataRows));
- __m256i zero = _mm256_setzero_si256();
-
- // [16] a3 b3 g3 r3 a2 b2 g2 r2 a1 b1 g1 r1 a0 b0 g0 r0
- __m256i pixels_0123_16bit = _mm256_unpacklo_epi8(pixels, zero);
-
- __m256i scaled_0123_hi = _mm256_mulhi_epi16(pixels_0123_16bit, coefs),
- scaled_0123_lo = _mm256_mullo_epi16(pixels_0123_16bit, coefs);
-
- // [32] c*a1 c*b1 c*g1 c*r1 c*a0 c*b0 c*g0 c*r0
- *accum01 = _mm256_add_epi32(*accum01, _mm256_unpacklo_epi16(scaled_0123_lo, scaled_0123_hi));
- // [32] c*a3 c*b3 c*g3 c*r3 c*a2 c*b2 c*g2 c*r2
- *accum23 = _mm256_add_epi32(*accum23, _mm256_unpackhi_epi16(scaled_0123_lo, scaled_0123_hi));
-
- // [16] a7 b7 g7 r7 a6 b6 g6 r6 a5 b5 g5 r5 a4 b4 g4 r4
- __m256i pixels_4567_16bit = _mm256_unpackhi_epi8(pixels, zero);
-
- __m256i scaled_4567_hi = _mm256_mulhi_epi16(pixels_4567_16bit, coefs),
- scaled_4567_lo = _mm256_mullo_epi16(pixels_4567_16bit, coefs);
-
- // [32] c*a5 c*b5 c*g5 c*r5 c*a4 c*b4 c*g4 c*r4
- *accum45 = _mm256_add_epi32(*accum45, _mm256_unpacklo_epi16(scaled_4567_lo, scaled_4567_hi));
- // [32] c*a7 c*b7 c*g7 c*r7 c*a6 c*b6 c*g6 c*r6
- *accum67 = _mm256_add_epi32(*accum67, _mm256_unpackhi_epi16(scaled_4567_lo, scaled_4567_hi));
- }
-
- template<bool hasAlpha>
- void ConvolveVertically(const SkConvolutionFilter1D::ConvolutionFixed* filterValues,
- int filterLength,
- unsigned char* const * sourceDataRows,
- int pixelWidth,
- unsigned char* outRow) {
- // Output eight pixels per iteration (32 bytes).
- for (int outX = 0; outX < pixelWidth; outX += 8) {
- // Accumulated result for each pixel. 32 bits per RGBA channel.
- __m256i accum01 = _mm256_setzero_si256();
- __m256i accum23 = _mm256_setzero_si256();
- __m256i accum45 = _mm256_setzero_si256();
- __m256i accum67 = _mm256_setzero_si256();
-
- // Convolve with 4 filter coefficient per iteration.
- int length = filterLength & ~3;
- for (int filterY = 0; filterY < length; filterY += 4) {
- compute_coefficient_row(filterValues[filterY + 0], sourceDataRows[filterY + 0] + outX * 4, &accum01, &accum23, &accum45, &accum67);
- compute_coefficient_row(filterValues[filterY + 1], sourceDataRows[filterY + 1] + outX * 4, &accum01, &accum23, &accum45, &accum67);
- compute_coefficient_row(filterValues[filterY + 2], sourceDataRows[filterY + 2] + outX * 4, &accum01, &accum23, &accum45, &accum67);
- compute_coefficient_row(filterValues[filterY + 3], sourceDataRows[filterY + 3] + outX * 4, &accum01, &accum23, &accum45, &accum67);
- }
- for (int filterY = length; filterY < filterLength; filterY++) {
- compute_coefficient_row(filterValues[filterY], sourceDataRows[filterY] + outX * 4, &accum01, &accum23, &accum45, &accum67);
- }
-
- // Shift right for fixed point implementation.
- accum01 = _mm256_srai_epi32(accum01, SkConvolutionFilter1D::kShiftBits);
- accum23 = _mm256_srai_epi32(accum23, SkConvolutionFilter1D::kShiftBits);
- accum45 = _mm256_srai_epi32(accum45, SkConvolutionFilter1D::kShiftBits);
- accum67 = _mm256_srai_epi32(accum67, SkConvolutionFilter1D::kShiftBits);
-
- // Packing 32 bits |accum| to 16 bits per channel (signed saturation).
- // [16] a3 b3 g3 r3 a2 b2 g2 r2 a1 b1 g1 r1 a0 b0 g0 r0
- __m256i accum_0123 = _mm256_packs_epi32(accum01, accum23);
-
- // Packing 32 bits |accum| to 16 bits per channel (signed saturation).
- // [16] a7 b7 g7 r7 a6 b6 g6 r6 a5 b5 g5 r5 a4 b4 g4 r4
- __m256i accum_4567 = _mm256_packs_epi32(accum45, accum67);
-
- // Packing 16 bits |accum| to 8 bits per channel (unsigned saturation).
- // [8] a7 b7 g7 r7 a6 b6 g6 r6 a5 b5 g5 r5 a4 b4 g4 r4 a3 b3 g3 r3 a2 b2 g2 r2 a1 b1 g1 r1 a0 b0 g0 r0
- __m256i accum = _mm256_packus_epi16(accum_0123, accum_4567);
-
- if (hasAlpha) {
- // Make sure the value of alpha channel is always larger than maximum
- // value of color channels.
- // If alpha is less than r, g, or b, set it to their max.
- __m256i max_rg = _mm256_max_epu8( accum, _mm256_srli_epi32(accum, 8));
- __m256i max_rgb = _mm256_max_epu8(max_rg, _mm256_srli_epi32(accum, 16));
- accum = _mm256_max_epu8(accum, _mm256_slli_epi32(max_rgb, 24));
- } else {
- // Force opaque.
- accum = _mm256_or_si256(accum, _mm256_set1_epi32(0xff000000));
- }
-
- // Store the convolution result (32 bytes) and advance the pixel pointers.
- // During the last iteration, when pixels left are less than 8, store them one at a time.
- if (outX + 8 <= pixelWidth) {
- _mm256_storeu_si256(reinterpret_cast<__m256i *>(outRow), accum);
- outRow += 32;
- } else {
- for (int i = outX; i < pixelWidth; i++) {
- *(reinterpret_cast<int*>(outRow)) = _mm_cvtsi128_si32(_mm256_castsi256_si128(accum));
- __m256i rotate = _mm256_setr_epi32(1, 2, 3, 4, 5, 6, 7, 0);
- accum = _mm256_permutevar8x32_epi32(accum, rotate);
- outRow += 4;
- }
- }
- }
- }
-#endif
-
#if SK_CPU_SSE_LEVEL >= SK_CPU_SSE_LEVEL_SSE2
static SK_ALWAYS_INLINE void AccumRemainder(const unsigned char* pixelsLeft,
}
}
-// If we've got AVX2, we've already defined a faster ConvolveVertically above.
-#if SK_CPU_SSE_LEVEL < SK_CPU_SSE_LEVEL_AVX2
// 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 |sourceDataRows| array, with each row
}
}
}
-#endif//SK_CPU_SSE_LEVEL < SK_CPU_SSE_LEVEL_AVX2
#elif defined(SK_ARM_HAS_NEON)
* found in the LICENSE file.
*/
-#include "SkSafe_math.h" // Keep this first.
+// It is not safe to #include any header file here unless it has been vetted for ODR safety:
+// all symbols used must be file-scoped static or in an anonymous namespace. This applies
+// to _all_ header files: C standard library, C++ standard library, Skia... everything.
-// Please note carefully.
-// It is not safe for _opts.h files included here to use STL types, for the
-// same reason we just had to include SkSafe_math.h: STL types are templated,
-// defined in headers, but not in anonymous namespaces. It's very easy to
-// cause ODR violations with these types and AVX+ code generation.
+#include <immintrin.h> // ODR safe
+#include <stdint.h> // ODR safe
-#include "SkOpts.h"
-#define SK_OPTS_NS hsw
-#include "SkBitmapFilter_opts.h"
+namespace hsw {
-#if defined(_INC_MATH) && !defined(INC_MATH_IS_SAFE_NOW)
- #error We have included ucrt\math.h without protecting it against ODR violation.
-#endif
+ void convolve_vertically(const int16_t* filter, int filterLen,
+ uint8_t* const* srcRows, int width,
+ uint8_t* out, bool hasAlpha) {
+ // It's simpler to work with the output array in terms of 4-byte pixels.
+ auto dst = (int*)out;
+
+ // Output up to eight pixels per iteration.
+ for (int x = 0; x < width; x += 8) {
+ // Accumulated result for 4 adjacent pairs of pixels, in signed 17.14 fixed point.
+ auto accum01 = _mm256_setzero_si256(),
+ accum23 = _mm256_setzero_si256(),
+ accum45 = _mm256_setzero_si256(),
+ accum67 = _mm256_setzero_si256();
+
+ // Convolve with the filter. (This inner loop is where we spend ~all our time.)
+ for (int i = 0; i < filterLen; i++) {
+ auto coeffs = _mm256_set1_epi16(filter[i]);
+ auto pixels = _mm256_loadu_si256((const __m256i*)(srcRows[i] + x*4));
+
+ auto pixels_0123 = _mm256_unpacklo_epi8(pixels, _mm256_setzero_si256()),
+ pixels_4567 = _mm256_unpackhi_epi8(pixels, _mm256_setzero_si256());
+
+ auto lo_0123 = _mm256_mullo_epi16(pixels_0123, coeffs),
+ hi_0123 = _mm256_mulhi_epi16(pixels_0123, coeffs),
+ lo_4567 = _mm256_mullo_epi16(pixels_4567, coeffs),
+ hi_4567 = _mm256_mulhi_epi16(pixels_4567, coeffs);
+
+ accum01 = _mm256_add_epi32(accum01, _mm256_unpacklo_epi16(lo_0123, hi_0123));
+ accum23 = _mm256_add_epi32(accum23, _mm256_unpackhi_epi16(lo_0123, hi_0123));
+ accum45 = _mm256_add_epi32(accum45, _mm256_unpacklo_epi16(lo_4567, hi_4567));
+ accum67 = _mm256_add_epi32(accum67, _mm256_unpackhi_epi16(lo_4567, hi_4567));
+ }
+
+ // Trim the fractional parts.
+ accum01 = _mm256_srai_epi32(accum01, 14);
+ accum23 = _mm256_srai_epi32(accum23, 14);
+ accum45 = _mm256_srai_epi32(accum45, 14);
+ accum67 = _mm256_srai_epi32(accum67, 14);
+
+ // Pack back down to 8-bit channels.
+ auto pixels = _mm256_packus_epi16(_mm256_packs_epi32(accum01, accum23),
+ _mm256_packs_epi32(accum45, accum67));
+
+ if (hasAlpha) {
+ // Clamp alpha to the max of r,g,b to make sure we stay premultiplied.
+ __m256i max_rg = _mm256_max_epu8(pixels, _mm256_srli_epi32(pixels, 8)),
+ max_rgb = _mm256_max_epu8(max_rg, _mm256_srli_epi32(pixels, 16));
+ pixels = _mm256_max_epu8(pixels, _mm256_slli_epi32(max_rgb, 24));
+ } else {
+ // Force opaque.
+ pixels = _mm256_or_si256(pixels, _mm256_set1_epi32(0xff000000));
+ }
+
+ // Normal path to store 8 pixels.
+ if (x + 8 <= width) {
+ _mm256_storeu_si256((__m256i*)dst, pixels);
+ dst += 8;
+ continue;
+ }
+
+ // Store one pixel at a time on the last iteration.
+ for (int i = x; i < width; i++) {
+ *dst++ = _mm_cvtsi128_si32(_mm256_castsi256_si128(pixels));
+ pixels = _mm256_permutevar8x32_epi32(pixels, _mm256_setr_epi32(1,2,3,4,5,6,7,0));
+ }
+ }
+ }
+
+}
namespace SkOpts {
+ // See SkOpts.h, writing SkConvolutionFilter1D::ConvolutionFixed as the underlying type.
+ extern void (*convolve_vertically)(const int16_t* filter, int filterLen,
+ uint8_t* const* srcRows, int width,
+ uint8_t* out, bool hasAlpha);
void Init_hsw() {
convolve_vertically = hsw::convolve_vertically;
}
}
-