Port convolve functions to SkOpts

src/opts/SkBitmapProcState_arm_neon.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmapProcState.h"
 #include "SkBitmapProcState_filter.h"
 #include "SkColorPriv.h"
@@ skipping 59 matching lines @@
     // todo: possibly specialize on opaqueness
     SG8_alpha_D32_nofilter_DXDY_neon,
     SG8_alpha_D32_nofilter_DXDY_neon,
     SG8_alpha_D32_nofilter_DX_neon,
     SG8_alpha_D32_nofilter_DX_neon,
     SG8_alpha_D32_filter_DXDY_neon,
     SG8_alpha_D32_filter_DXDY_neon,
     SG8_alpha_D32_filter_DX_neon,
     SG8_alpha_D32_filter_DX_neon,
 };
-
-///////////////////////////////////////////////////////////////////////////////
-
-#include <arm_neon.h>
-#include "SkConvolver.h"
-
-static SK_ALWAYS_INLINE void accum_remainder(const unsigned char* pixels_left,
-        const SkConvolutionFilter1D::ConvolutionFixed* filter_values, int32x4_t& accum, int r) {
-    int remainder[4] = {0};
-    for (int i = 0; i < r; i++) {
-        SkConvolutionFilter1D::ConvolutionFixed coeff = filter_values[i];
-        remainder[0] += coeff * pixels_left[i * 4 + 0];
-        remainder[1] += coeff * pixels_left[i * 4 + 1];
-        remainder[2] += coeff * pixels_left[i * 4 + 2];
-        remainder[3] += coeff * pixels_left[i * 4 + 3];
-    }
-    int32x4_t t = {remainder[0], remainder[1], remainder[2], remainder[3]};
-    accum += t;
-}
-
-// Convolves horizontally along a single row. The row data is given in
-// |srcData| and continues for the numValues() of the filter.
-void convolveHorizontally_neon(const unsigned char* srcData,
-                               const SkConvolutionFilter1D& filter,
-                               unsigned char* outRow,
-                               bool hasAlpha) {
-    // Loop over each pixel on this row in the output image.
-    int numValues = filter.numValues();
-    for (int outX = 0; outX < numValues; outX++) {
-        uint8x8_t coeff_mask0 = vcreate_u8(0x0100010001000100);
-        uint8x8_t coeff_mask1 = vcreate_u8(0x0302030203020302);
-        uint8x8_t coeff_mask2 = vcreate_u8(0x0504050405040504);
-        uint8x8_t coeff_mask3 = vcreate_u8(0x0706070607060706);
-        // Get the filter that determines the current output pixel.
-        int filterOffset, filterLength;
-        const SkConvolutionFilter1D::ConvolutionFixed* filterValues =
-            filter.FilterForValue(outX, &filterOffset, &filterLength);
-
-        // Compute the first pixel in this row that the filter affects. It will
-        // touch |filterLength| pixels (4 bytes each) after this.
-        const unsigned char* rowToFilter = &srcData[filterOffset * 4];
-
-        // Apply the filter to the row to get the destination pixel in |accum|.
-        int32x4_t accum = vdupq_n_s32(0);
-        for (int filterX = 0; filterX < filterLength >> 2; filterX++) {
-            // Load 4 coefficients
-            int16x4_t coeffs, coeff0, coeff1, coeff2, coeff3;
-            coeffs = vld1_s16(filterValues);
-            coeff0 = vreinterpret_s16_u8(vtbl1_u8(vreinterpret_u8_s16(coeffs), coeff_mask0));
-            coeff1 = vreinterpret_s16_u8(vtbl1_u8(vreinterpret_u8_s16(coeffs), coeff_mask1));
-            coeff2 = vreinterpret_s16_u8(vtbl1_u8(vreinterpret_u8_s16(coeffs), coeff_mask2));
-            coeff3 = vreinterpret_s16_u8(vtbl1_u8(vreinterpret_u8_s16(coeffs), coeff_mask3));
-
-            // Load pixels and calc
-            uint8x16_t pixels = vld1q_u8(rowToFilter);
-            int16x8_t p01_16 = vreinterpretq_s16_u16(vmovl_u8(vget_low_u8(pixels)));
-            int16x8_t p23_16 = vreinterpretq_s16_u16(vmovl_u8(vget_high_u8(pixels)));
-
-            int16x4_t p0_src = vget_low_s16(p01_16);
-            int16x4_t p1_src = vget_high_s16(p01_16);
-            int16x4_t p2_src = vget_low_s16(p23_16);
-            int16x4_t p3_src = vget_high_s16(p23_16);
-
-            int32x4_t p0 = vmull_s16(p0_src, coeff0);
-            int32x4_t p1 = vmull_s16(p1_src, coeff1);
-            int32x4_t p2 = vmull_s16(p2_src, coeff2);
-            int32x4_t p3 = vmull_s16(p3_src, coeff3);
-
-            accum += p0;
-            accum += p1;
-            accum += p2;
-            accum += p3;
-
-            // Advance the pointers
-            rowToFilter += 16;
-            filterValues += 4;
-        }
-
-        int r = filterLength & 3;
-        if (r) {
-            int remainder_offset = (filterOffset + filterLength - r) * 4;
-            accum_remainder(srcData + remainder_offset, filterValues, accum, r);
-        }
-
-        // Bring this value back in range. All of the filter scaling factors
-        // are in fixed point with kShiftBits bits of fractional part.
-        accum = vshrq_n_s32(accum, SkConvolutionFilter1D::kShiftBits);
-
-        // Pack and store the new pixel.
-        int16x4_t accum16 = vqmovn_s32(accum);
-        uint8x8_t accum8 = vqmovun_s16(vcombine_s16(accum16, accum16));
-        vst1_lane_u32(reinterpret_cast<uint32_t*>(outRow), vreinterpret_u32_u8(accum8), 0);
-        outRow += 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 |sourceDataRows| array, with each row
-// being |pixelWidth| wide.
-//
-// The output must have room for |pixelWidth * 4| bytes.
-template<bool hasAlpha>
-void convolveVertically_neon(const SkConvolutionFilter1D::ConvolutionFixed* filterValues,
-                             int filterLength,
-                             unsigned char* const* sourceDataRows,
-                             int pixelWidth,
-                             unsigned char* outRow) {
-    int width = pixelWidth & ~3;
-
-    int32x4_t accum0, accum1, accum2, accum3;
-    int16x4_t coeff16;
-
-    // Output four pixels per iteration (16 bytes).
-    for (int outX = 0; outX < width; outX += 4) {
-
-        // Accumulated result for each pixel. 32 bits per RGBA channel.
-        accum0 = accum1 = accum2 = accum3 = vdupq_n_s32(0);
-
-        // Convolve with one filter coefficient per iteration.
-        for (int filterY = 0; filterY < filterLength; filterY++) {
-
-            // Duplicate the filter coefficient 4 times.
-            // [16] cj cj cj cj
-            coeff16 = vdup_n_s16(filterValues[filterY]);
-
-            // Load four pixels (16 bytes) together.
-            // [8] a3 b3 g3 r3 a2 b2 g2 r2 a1 b1 g1 r1 a0 b0 g0 r0
-            uint8x16_t src8 = vld1q_u8(&sourceDataRows[filterY][outX << 2]);
-
-            int16x8_t src16_01 = vreinterpretq_s16_u16(vmovl_u8(vget_low_u8(src8)));
-            int16x8_t src16_23 = vreinterpretq_s16_u16(vmovl_u8(vget_high_u8(src8)));
-            int16x4_t src16_0 = vget_low_s16(src16_01);
-            int16x4_t src16_1 = vget_high_s16(src16_01);
-            int16x4_t src16_2 = vget_low_s16(src16_23);
-            int16x4_t src16_3 = vget_high_s16(src16_23);
-
-            accum0 += vmull_s16(src16_0, coeff16);
-            accum1 += vmull_s16(src16_1, coeff16);
-            accum2 += vmull_s16(src16_2, coeff16);
-            accum3 += vmull_s16(src16_3, coeff16);
-        }
-
-        // Shift right for fixed point implementation.
-        accum0 = vshrq_n_s32(accum0, SkConvolutionFilter1D::kShiftBits);
-        accum1 = vshrq_n_s32(accum1, SkConvolutionFilter1D::kShiftBits);
-        accum2 = vshrq_n_s32(accum2, SkConvolutionFilter1D::kShiftBits);
-        accum3 = vshrq_n_s32(accum3, SkConvolutionFilter1D::kShiftBits);
-
-        // Packing 32 bits |accum| to 16 bits per channel (signed saturation).
-        // [16] a1 b1 g1 r1 a0 b0 g0 r0
-        int16x8_t accum16_0 = vcombine_s16(vqmovn_s32(accum0), vqmovn_s32(accum1));
-        // [16] a3 b3 g3 r3 a2 b2 g2 r2
-        int16x8_t accum16_1 = vcombine_s16(vqmovn_s32(accum2), vqmovn_s32(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
-        uint8x16_t accum8 = vcombine_u8(vqmovun_s16(accum16_0), vqmovun_s16(accum16_1));
-
-        if (hasAlpha) {
-            // 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
-            uint8x16_t a = vreinterpretq_u8_u32(vshrq_n_u32(vreinterpretq_u32_u8(accum8), 8));
-            // [8] xx xx xx max3 xx xx xx max2 xx xx xx max1 xx xx xx max0
-            uint8x16_t b = vmaxq_u8(a, accum8); // Max of r and g
-            // [8] xx xx a3 b3 xx xx a2 b2 xx xx a1 b1 xx xx a0 b0
-            a = vreinterpretq_u8_u32(vshrq_n_u32(vreinterpretq_u32_u8(accum8), 16));
-            // [8] xx xx xx max3 xx xx xx max2 xx xx xx max1 xx xx xx max0
-            b = vmaxq_u8(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 = vreinterpretq_u8_u32(vshlq_n_u32(vreinterpretq_u32_u8(b), 24));
-
-            // Make sure the value of alpha channel is always larger than maximum
-            // value of color channels.
-            accum8 = vmaxq_u8(b, accum8);
-        } else {
-            // Set value of alpha channels to 0xFF.
-            accum8 = vreinterpretq_u8_u32(vreinterpretq_u32_u8(accum8) | vdupq_n_u32(0xFF000000));
-        }
-
-        // Store the convolution result (16 bytes) and advance the pixel pointers.
-        vst1q_u8(outRow, accum8);
-        outRow += 16;
-    }
-
-    // Process the leftovers when the width of the output is not divisible
-    // by 4, that is at most 3 pixels.
-    int r = pixelWidth & 3;
-    if (r) {
-
-        accum0 = accum1 = accum2 = vdupq_n_s32(0);
-
-        for (int filterY = 0; filterY < filterLength; ++filterY) {
-            coeff16 = vdup_n_s16(filterValues[filterY]);
-
-            // [8] a3 b3 g3 r3 a2 b2 g2 r2 a1 b1 g1 r1 a0 b0 g0 r0
-            uint8x16_t src8 = vld1q_u8(&sourceDataRows[filterY][width << 2]);
-
-            int16x8_t src16_01 = vreinterpretq_s16_u16(vmovl_u8(vget_low_u8(src8)));
-            int16x8_t src16_23 = vreinterpretq_s16_u16(vmovl_u8(vget_high_u8(src8)));
-            int16x4_t src16_0 = vget_low_s16(src16_01);
-            int16x4_t src16_1 = vget_high_s16(src16_01);
-            int16x4_t src16_2 = vget_low_s16(src16_23);
-
-            accum0 += vmull_s16(src16_0, coeff16);
-            accum1 += vmull_s16(src16_1, coeff16);
-            accum2 += vmull_s16(src16_2, coeff16);
-        }
-
-        accum0 = vshrq_n_s32(accum0, SkConvolutionFilter1D::kShiftBits);
-        accum1 = vshrq_n_s32(accum1, SkConvolutionFilter1D::kShiftBits);
-        accum2 = vshrq_n_s32(accum2, SkConvolutionFilter1D::kShiftBits);
-
-        int16x8_t accum16_0 = vcombine_s16(vqmovn_s32(accum0), vqmovn_s32(accum1));
-        int16x8_t accum16_1 = vcombine_s16(vqmovn_s32(accum2), vqmovn_s32(accum2));
-
-        uint8x16_t accum8 = vcombine_u8(vqmovun_s16(accum16_0), vqmovun_s16(accum16_1));
-
-        if (hasAlpha) {
-            // 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
-            uint8x16_t a = vreinterpretq_u8_u32(vshrq_n_u32(vreinterpretq_u32_u8(accum8), 8));
-            // [8] xx xx xx max3 xx xx xx max2 xx xx xx max1 xx xx xx max0
-            uint8x16_t b = vmaxq_u8(a, accum8); // Max of r and g
-            // [8] xx xx a3 b3 xx xx a2 b2 xx xx a1 b1 xx xx a0 b0
-            a = vreinterpretq_u8_u32(vshrq_n_u32(vreinterpretq_u32_u8(accum8), 16));
-            // [8] xx xx xx max3 xx xx xx max2 xx xx xx max1 xx xx xx max0
-            b = vmaxq_u8(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 = vreinterpretq_u8_u32(vshlq_n_u32(vreinterpretq_u32_u8(b), 24));
-
-            // Make sure the value of alpha channel is always larger than maximum
-            // value of color channels.
-            accum8 = vmaxq_u8(b, accum8);
-        } else {
-            // Set value of alpha channels to 0xFF.
-            accum8 = vreinterpretq_u8_u32(vreinterpretq_u32_u8(accum8) | vdupq_n_u32(0xFF000000));
-        }
-
-        switch(r) {
-        case 1:
-            vst1q_lane_u32(reinterpret_cast<uint32_t*>(outRow), vreinterpretq_u32_u8(accum8), 0);
-            break;
-        case 2:
-            vst1_u32(reinterpret_cast<uint32_t*>(outRow),
-                     vreinterpret_u32_u8(vget_low_u8(accum8)));
-            break;
-        case 3:
-            vst1_u32(reinterpret_cast<uint32_t*>(outRow),
-                     vreinterpret_u32_u8(vget_low_u8(accum8)));
-            vst1q_lane_u32(reinterpret_cast<uint32_t*>(outRow+8), vreinterpretq_u32_u8(accum8), 2);
-            break;
-        }
-    }
-}
-
-void convolveVertically_neon(const SkConvolutionFilter1D::ConvolutionFixed* filterValues,
-                             int filterLength,
-                             unsigned char* const* sourceDataRows,
-                             int pixelWidth,
-                             unsigned char* outRow,
-                             bool sourceHasAlpha) {
-    if (sourceHasAlpha) {
-        convolveVertically_neon<true>(filterValues, filterLength,
-                                      sourceDataRows, pixelWidth,
-                                      outRow);
-    } else {
-        convolveVertically_neon<false>(filterValues, filterLength,
-                                       sourceDataRows, pixelWidth,
-                                       outRow);
-    }
-}
-
-// 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_neon(const unsigned char* srcData[4],
-                                    const SkConvolutionFilter1D& filter,
-                                    unsigned char* outRow[4],
-                                    size_t outRowBytes) {
-
-    uint8x8_t coeff_mask0 = vcreate_u8(0x0100010001000100);
-    uint8x8_t coeff_mask1 = vcreate_u8(0x0302030203020302);
-    uint8x8_t coeff_mask2 = vcreate_u8(0x0504050405040504);
-    uint8x8_t coeff_mask3 = vcreate_u8(0x0706070607060706);
-    int num_values = filter.numValues();
-
-    int filterOffset, filterLength;
-
-    // Output one pixel each iteration, calculating all channels (RGBA) together.
-    for (int outX = 0; outX < num_values; outX++) {
-
-        const SkConvolutionFilter1D::ConvolutionFixed* filterValues =
-        filter.FilterForValue(outX, &filterOffset, &filterLength);
-
-        // four pixels in a column per iteration.
-        int32x4_t accum0 = vdupq_n_s32(0);
-        int32x4_t accum1 = vdupq_n_s32(0);
-        int32x4_t accum2 = vdupq_n_s32(0);
-        int32x4_t accum3 = vdupq_n_s32(0);
-
-        int start = (filterOffset<<2);
-
-        // We will load and accumulate with four coefficients per iteration.
-        for (int filter_x = 0; filter_x < (filterLength >> 2); filter_x++) {
-            int16x4_t coeffs, coeff0, coeff1, coeff2, coeff3;
-
-            coeffs = vld1_s16(filterValues);
-            coeff0 = vreinterpret_s16_u8(vtbl1_u8(vreinterpret_u8_s16(coeffs), coeff_mask0));
-            coeff1 = vreinterpret_s16_u8(vtbl1_u8(vreinterpret_u8_s16(coeffs), coeff_mask1));
-            coeff2 = vreinterpret_s16_u8(vtbl1_u8(vreinterpret_u8_s16(coeffs), coeff_mask2));
-            coeff3 = vreinterpret_s16_u8(vtbl1_u8(vreinterpret_u8_s16(coeffs), coeff_mask3));
-
-            uint8x16_t pixels;
-            int16x8_t p01_16, p23_16;
-            int32x4_t p0, p1, p2, p3;
-
-
-#define ITERATION(src, accum)                                       \
-    pixels = vld1q_u8(src);                                         \
-    p01_16 = vreinterpretq_s16_u16(vmovl_u8(vget_low_u8(pixels)));  \
-    p23_16 = vreinterpretq_s16_u16(vmovl_u8(vget_high_u8(pixels))); \
-    p0 = vmull_s16(vget_low_s16(p01_16), coeff0);                   \
-    p1 = vmull_s16(vget_high_s16(p01_16), coeff1);                  \
-    p2 = vmull_s16(vget_low_s16(p23_16), coeff2);                   \
-    p3 = vmull_s16(vget_high_s16(p23_16), coeff3);                  \
-    accum += p0;                                                    \
-    accum += p1;                                                    \
-    accum += p2;                                                    \
-    accum += p3
-
-            ITERATION(srcData[0] + start, accum0);
-            ITERATION(srcData[1] + start, accum1);
-            ITERATION(srcData[2] + start, accum2);
-            ITERATION(srcData[3] + start, accum3);
-
-            start += 16;
-            filterValues += 4;
-        }
-
-        int r = filterLength & 3;
-        if (r) {
-            int remainder_offset = (filterOffset + filterLength - r) * 4;
-            accum_remainder(srcData[0] + remainder_offset, filterValues, accum0, r);
-            accum_remainder(srcData[1] + remainder_offset, filterValues, accum1, r);
-            accum_remainder(srcData[2] + remainder_offset, filterValues, accum2, r);
-            accum_remainder(srcData[3] + remainder_offset, filterValues, accum3, r);
-        }
-
-        int16x4_t accum16;
-        uint8x8_t res0, res1, res2, res3;
-
-#define PACK_RESULT(accum, res)                                         \
-        accum = vshrq_n_s32(accum, SkConvolutionFilter1D::kShiftBits);  \
-        accum16 = vqmovn_s32(accum);                                    \
-        res = vqmovun_s16(vcombine_s16(accum16, accum16));
-
-        PACK_RESULT(accum0, res0);
-        PACK_RESULT(accum1, res1);
-        PACK_RESULT(accum2, res2);
-        PACK_RESULT(accum3, res3);
-
-        vst1_lane_u32(reinterpret_cast<uint32_t*>(outRow[0]), vreinterpret_u32_u8(res0), 0);
-        vst1_lane_u32(reinterpret_cast<uint32_t*>(outRow[1]), vreinterpret_u32_u8(res1), 0);
-        vst1_lane_u32(reinterpret_cast<uint32_t*>(outRow[2]), vreinterpret_u32_u8(res2), 0);
-        vst1_lane_u32(reinterpret_cast<uint32_t*>(outRow[3]), vreinterpret_u32_u8(res3), 0);
-        outRow[0] += 4;
-        outRow[1] += 4;
-        outRow[2] += 4;
-        outRow[3] += 4;
-    }
-}
-
-void platformConvolutionProcs_arm_neon(SkConvolutionProcs* procs) {
-    procs->fConvolveVertically = &convolveVertically_neon;
-    procs->fConvolve4RowsHorizontally = &convolve4RowsHorizontally_neon;
-    procs->fConvolveHorizontally = &convolveHorizontally_neon;
-}