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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#include "Blur.h"
#include <arm_neon.h>
namespace mozilla {
namespace gfx {
MOZ_ALWAYS_INLINE
uint16x4_t Divide(uint32x4_t aValues, uint32x2_t aDivisor) {
uint64x2_t roundingAddition = vdupq_n_u64(int64_t(1) << 31);
uint64x2_t multiplied21 = vmull_u32(vget_low_u32(aValues), aDivisor);
uint64x2_t multiplied43 = vmull_u32(vget_high_u32(aValues), aDivisor);
return vqmovn_u32(
vcombine_u32(vshrn_n_u64(vaddq_u64(multiplied21, roundingAddition), 32),
vshrn_n_u64(vaddq_u64(multiplied43, roundingAddition), 32)));
}
MOZ_ALWAYS_INLINE
uint16x4_t BlurFourPixels(const uint32x4_t& aTopLeft,
const uint32x4_t& aTopRight,
const uint32x4_t& aBottomRight,
const uint32x4_t& aBottomLeft,
const uint32x2_t& aDivisor) {
uint32x4_t values = vaddq_u32(
vsubq_u32(vsubq_u32(aBottomRight, aTopRight), aBottomLeft), aTopLeft);
return Divide(values, aDivisor);
}
MOZ_ALWAYS_INLINE
void LoadIntegralRowFromRow(uint32_t* aDest, const uint8_t* aSource,
int32_t aSourceWidth, int32_t aLeftInflation,
int32_t aRightInflation) {
int32_t currentRowSum = 0;
for (int x = 0; x < aLeftInflation; x++) {
currentRowSum += aSource[0];
aDest[x] = currentRowSum;
}
for (int x = aLeftInflation; x < (aSourceWidth + aLeftInflation); x++) {
currentRowSum += aSource[(x - aLeftInflation)];
aDest[x] = currentRowSum;
}
for (int x = (aSourceWidth + aLeftInflation);
x < (aSourceWidth + aLeftInflation + aRightInflation); x++) {
currentRowSum += aSource[aSourceWidth - 1];
aDest[x] = currentRowSum;
}
}
MOZ_ALWAYS_INLINE void GenerateIntegralImage_NEON(
int32_t aLeftInflation, int32_t aRightInflation, int32_t aTopInflation,
int32_t aBottomInflation, uint32_t* aIntegralImage,
size_t aIntegralImageStride, uint8_t* aSource, int32_t aSourceStride,
const IntSize& aSize) {
MOZ_ASSERT(!(aLeftInflation & 3));
uint32_t stride32bit = aIntegralImageStride / 4;
IntSize integralImageSize(aSize.width + aLeftInflation + aRightInflation,
aSize.height + aTopInflation + aBottomInflation);
LoadIntegralRowFromRow(aIntegralImage, aSource, aSize.width, aLeftInflation,
aRightInflation);
for (int y = 1; y < aTopInflation + 1; y++) {
uint32_t* intRow = aIntegralImage + (y * stride32bit);
uint32_t* intPrevRow = aIntegralImage + (y - 1) * stride32bit;
uint32_t* intFirstRow = aIntegralImage;
for (int x = 0; x < integralImageSize.width; x += 4) {
uint32x4_t firstRow = vld1q_u32(intFirstRow + x);
uint32x4_t previousRow = vld1q_u32(intPrevRow + x);
vst1q_u32(intRow + x, vaddq_u32(firstRow, previousRow));
}
}
for (int y = aTopInflation + 1; y < (aSize.height + aTopInflation); y++) {
uint32x4_t currentRowSum = vdupq_n_u32(0);
uint32_t* intRow = aIntegralImage + (y * stride32bit);
uint32_t* intPrevRow = aIntegralImage + (y - 1) * stride32bit;
uint8_t* sourceRow = aSource + aSourceStride * (y - aTopInflation);
uint32_t pixel = sourceRow[0];
for (int x = 0; x < aLeftInflation; x += 4) {
uint32_t temp[4];
temp[0] = pixel;
temp[1] = temp[0] + pixel;
temp[2] = temp[1] + pixel;
temp[3] = temp[2] + pixel;
uint32x4_t sumPixels = vld1q_u32(temp);
sumPixels = vaddq_u32(sumPixels, currentRowSum);
currentRowSum = vdupq_n_u32(vgetq_lane_u32(sumPixels, 3));
vst1q_u32(intRow + x, vaddq_u32(sumPixels, vld1q_u32(intPrevRow + x)));
}
for (int x = aLeftInflation; x < (aSize.width + aLeftInflation); x += 4) {
// It's important to shuffle here. When we exit this loop currentRowSum
// has to be set to sumPixels, so that the following loop can get the
// correct pixel for the currentRowSum. The highest order pixel in
// currentRowSum could've originated from accumulation in the stride.
currentRowSum = vdupq_n_u32(vgetq_lane_u32(currentRowSum, 3));
uint32_t temp[4];
temp[0] = *(sourceRow + (x - aLeftInflation));
temp[1] = temp[0] + *(sourceRow + (x - aLeftInflation) + 1);
temp[2] = temp[1] + *(sourceRow + (x - aLeftInflation) + 2);
temp[3] = temp[2] + *(sourceRow + (x - aLeftInflation) + 3);
uint32x4_t sumPixels = vld1q_u32(temp);
sumPixels = vaddq_u32(sumPixels, currentRowSum);
currentRowSum = sumPixels;
vst1q_u32(intRow + x, vaddq_u32(sumPixels, vld1q_u32(intPrevRow + x)));
}
pixel = sourceRow[aSize.width - 1];
int x = (aSize.width + aLeftInflation);
if ((aSize.width & 3)) {
// Deal with unaligned portion. Get the correct pixel from currentRowSum,
// see explanation above.
uint32_t intCurrentRowSum =
((uint32_t*)¤tRowSum)[(aSize.width % 4) - 1];
for (; x < integralImageSize.width; x++) {
// We could be unaligned here!
if (!(x & 3)) {
// aligned!
currentRowSum = vdupq_n_u32(intCurrentRowSum);
break;
}
intCurrentRowSum += pixel;
intRow[x] = intPrevRow[x] + intCurrentRowSum;
}
} else {
currentRowSum = vdupq_n_u32(vgetq_lane_u32(currentRowSum, 3));
}
for (; x < integralImageSize.width; x += 4) {
uint32_t temp[4];
temp[0] = pixel;
temp[1] = temp[0] + pixel;
temp[2] = temp[1] + pixel;
temp[3] = temp[2] + pixel;
uint32x4_t sumPixels = vld1q_u32(temp);
sumPixels = vaddq_u32(sumPixels, currentRowSum);
currentRowSum = vdupq_n_u32(vgetq_lane_u32(sumPixels, 3));
vst1q_u32(intRow + x, vaddq_u32(sumPixels, vld1q_u32(intPrevRow + x)));
}
}
if (aBottomInflation) {
// Store the last valid row of our source image in the last row of
// our integral image. This will be overwritten with the correct values
// in the upcoming loop.
LoadIntegralRowFromRow(
aIntegralImage + (integralImageSize.height - 1) * stride32bit,
aSource + (aSize.height - 1) * aSourceStride, aSize.width,
aLeftInflation, aRightInflation);
for (int y = aSize.height + aTopInflation; y < integralImageSize.height;
y++) {
uint32_t* intRow = aIntegralImage + (y * stride32bit);
uint32_t* intPrevRow = aIntegralImage + (y - 1) * stride32bit;
uint32_t* intLastRow =
aIntegralImage + (integralImageSize.height - 1) * stride32bit;
for (int x = 0; x < integralImageSize.width; x += 4) {
vst1q_u32(intRow + x, vaddq_u32(vld1q_u32(intLastRow + x),
vld1q_u32(intPrevRow + x)));
}
}
}
}
/**
* Attempt to do an in-place box blur using an integral image.
*/
void AlphaBoxBlur::BoxBlur_NEON(uint8_t* aData, int32_t aLeftLobe,
int32_t aRightLobe, int32_t aTopLobe,
int32_t aBottomLobe, uint32_t* aIntegralImage,
size_t aIntegralImageStride) const {
IntSize size = GetSize();
MOZ_ASSERT(size.height > 0);
// Our 'left' or 'top' lobe will include the current pixel. i.e. when
// looking at an integral image the value of a pixel at 'x,y' is calculated
// using the value of the integral image values above/below that.
aLeftLobe++;
aTopLobe++;
int32_t boxSize = (aLeftLobe + aRightLobe) * (aTopLobe + aBottomLobe);
MOZ_ASSERT(boxSize > 0);
if (boxSize == 1) {
return;
}
uint32_t reciprocal = uint32_t((uint64_t(1) << 32) / boxSize);
uint32_t stride32bit = aIntegralImageStride / 4;
int32_t leftInflation = RoundUpToMultipleOf4(aLeftLobe).value();
GenerateIntegralImage_NEON(leftInflation, aRightLobe, aTopLobe, aBottomLobe,
aIntegralImage, aIntegralImageStride, aData,
mStride, size);
uint32x2_t divisor = vdup_n_u32(reciprocal);
// This points to the start of the rectangle within the IntegralImage that
// overlaps the surface being blurred.
uint32_t* innerIntegral =
aIntegralImage + (aTopLobe * stride32bit) + leftInflation;
IntRect skipRect = mSkipRect;
int32_t stride = mStride;
uint8_t* data = aData;
for (int32_t y = 0; y < size.height; y++) {
bool inSkipRectY = y > skipRect.y && y < skipRect.YMost();
uint32_t* topLeftBase =
innerIntegral + ((y - aTopLobe) * ptrdiff_t(stride32bit) - aLeftLobe);
uint32_t* topRightBase =
innerIntegral + ((y - aTopLobe) * ptrdiff_t(stride32bit) + aRightLobe);
uint32_t* bottomRightBase =
innerIntegral +
((y + aBottomLobe) * ptrdiff_t(stride32bit) + aRightLobe);
uint32_t* bottomLeftBase =
innerIntegral +
((y + aBottomLobe) * ptrdiff_t(stride32bit) - aLeftLobe);
int32_t x = 0;
// Process 16 pixels at a time for as long as possible.
for (; x <= size.width - 16; x += 16) {
if (inSkipRectY && x > skipRect.x && x < skipRect.XMost()) {
x = skipRect.XMost() - 16;
// Trigger early jump on coming loop iterations, this will be reset
// next line anyway.
inSkipRectY = false;
continue;
}
uint32x4_t topLeft;
uint32x4_t topRight;
uint32x4_t bottomRight;
uint32x4_t bottomLeft;
topLeft = vld1q_u32(topLeftBase + x);
topRight = vld1q_u32(topRightBase + x);
bottomRight = vld1q_u32(bottomRightBase + x);
bottomLeft = vld1q_u32(bottomLeftBase + x);
uint16x4_t result1 =
BlurFourPixels(topLeft, topRight, bottomRight, bottomLeft, divisor);
topLeft = vld1q_u32(topLeftBase + x + 4);
topRight = vld1q_u32(topRightBase + x + 4);
bottomRight = vld1q_u32(bottomRightBase + x + 4);
bottomLeft = vld1q_u32(bottomLeftBase + x + 4);
uint16x4_t result2 =
BlurFourPixels(topLeft, topRight, bottomRight, bottomLeft, divisor);
topLeft = vld1q_u32(topLeftBase + x + 8);
topRight = vld1q_u32(topRightBase + x + 8);
bottomRight = vld1q_u32(bottomRightBase + x + 8);
bottomLeft = vld1q_u32(bottomLeftBase + x + 8);
uint16x4_t result3 =
BlurFourPixels(topLeft, topRight, bottomRight, bottomLeft, divisor);
topLeft = vld1q_u32(topLeftBase + x + 12);
topRight = vld1q_u32(topRightBase + x + 12);
bottomRight = vld1q_u32(bottomRightBase + x + 12);
bottomLeft = vld1q_u32(bottomLeftBase + x + 12);
uint16x4_t result4 =
BlurFourPixels(topLeft, topRight, bottomRight, bottomLeft, divisor);
uint8x8_t combine1 = vqmovn_u16(vcombine_u16(result1, result2));
uint8x8_t combine2 = vqmovn_u16(vcombine_u16(result3, result4));
uint8x16_t final = vcombine_u8(combine1, combine2);
vst1q_u8(data + stride * y + x, final);
}
// Process the remaining pixels 4 bytes at a time.
for (; x < size.width; x += 4) {
if (inSkipRectY && x > skipRect.x && x < skipRect.XMost()) {
x = skipRect.XMost() - 4;
// Trigger early jump on coming loop iterations, this will be reset
// next line anyway.
inSkipRectY = false;
continue;
}
uint32x4_t topLeft = vld1q_u32(topLeftBase + x);
uint32x4_t topRight = vld1q_u32(topRightBase + x);
uint32x4_t bottomRight = vld1q_u32(bottomRightBase + x);
uint32x4_t bottomLeft = vld1q_u32(bottomLeftBase + x);
uint16x4_t result =
BlurFourPixels(topLeft, topRight, bottomRight, bottomLeft, divisor);
uint32x2_t final =
vreinterpret_u32_u8(vmovn_u16(vcombine_u16(result, vdup_n_u16(0))));
*(uint32_t*)(data + stride * y + x) = vget_lane_u32(final, 0);
}
}
}
} // namespace gfx
} // namespace mozilla