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diff --git a/gfx/2d/BlurSSE2.cpp b/gfx/2d/BlurSSE2.cpp
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+++ b/gfx/2d/BlurSSE2.cpp
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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
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "Blur.h"
+
+#include "SSEHelpers.h"
+
+#include <string.h>
+
+namespace mozilla::gfx {
+
+MOZ_ALWAYS_INLINE
+__m128i Divide(__m128i aValues, __m128i aDivisor) {
+  const __m128i mask = _mm_setr_epi32(0x0, 0xffffffff, 0x0, 0xffffffff);
+  static const union {
+    int64_t i64[2];
+    __m128i m;
+  } roundingAddition = {{int64_t(1) << 31, int64_t(1) << 31}};
+
+  __m128i multiplied31 = _mm_mul_epu32(aValues, aDivisor);
+  __m128i multiplied42 = _mm_mul_epu32(_mm_srli_epi64(aValues, 32), aDivisor);
+
+  // Add 1 << 31 before shifting or masking the lower 32 bits away, so that the
+  // result is rounded.
+  __m128i p_3_1 =
+      _mm_srli_epi64(_mm_add_epi64(multiplied31, roundingAddition.m), 32);
+  __m128i p4_2_ =
+      _mm_and_si128(_mm_add_epi64(multiplied42, roundingAddition.m), mask);
+  __m128i p4321 = _mm_or_si128(p_3_1, p4_2_);
+  return p4321;
+}
+
+MOZ_ALWAYS_INLINE
+__m128i BlurFourPixels(const __m128i& aTopLeft, const __m128i& aTopRight,
+                       const __m128i& aBottomRight, const __m128i& aBottomLeft,
+                       const __m128i& aDivisor) {
+  __m128i values = _mm_add_epi32(
+      _mm_sub_epi32(_mm_sub_epi32(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;
+  }
+}
+
+// This function calculates an integral of four pixels stored in the 4
+// 32-bit integers on aPixels. i.e. for { 30, 50, 80, 100 } this returns
+// { 30, 80, 160, 260 }. This seems to be the fastest way to do this after
+// much testing.
+MOZ_ALWAYS_INLINE
+__m128i AccumulatePixelSums(__m128i aPixels) {
+  __m128i sumPixels = aPixels;
+  __m128i currentPixels = _mm_slli_si128(aPixels, 4);
+  sumPixels = _mm_add_epi32(sumPixels, currentPixels);
+  currentPixels = _mm_unpacklo_epi64(_mm_setzero_si128(), sumPixels);
+
+  return _mm_add_epi32(sumPixels, currentPixels);
+}
+
+MOZ_ALWAYS_INLINE void GenerateIntegralImage_SSE2(
+    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) {
+      __m128i firstRow = _mm_load_si128((__m128i*)(intFirstRow + x));
+      __m128i previousRow = _mm_load_si128((__m128i*)(intPrevRow + x));
+      _mm_store_si128((__m128i*)(intRow + x),
+                      _mm_add_epi32(firstRow, previousRow));
+    }
+  }
+
+  for (int y = aTopInflation + 1; y < (aSize.height + aTopInflation); y++) {
+    __m128i currentRowSum = _mm_setzero_si128();
+    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) {
+      __m128i sumPixels = AccumulatePixelSums(
+          _mm_shuffle_epi32(_mm_set1_epi32(pixel), _MM_SHUFFLE(0, 0, 0, 0)));
+
+      sumPixels = _mm_add_epi32(sumPixels, currentRowSum);
+
+      currentRowSum = _mm_shuffle_epi32(sumPixels, _MM_SHUFFLE(3, 3, 3, 3));
+
+      _mm_store_si128(
+          (__m128i*)(intRow + x),
+          _mm_add_epi32(sumPixels, _mm_load_si128((__m128i*)(intPrevRow + x))));
+    }
+    for (int x = aLeftInflation; x < (aSize.width + aLeftInflation); x += 4) {
+      uint32_t pixels = *(uint32_t*)(sourceRow + (x - aLeftInflation));
+
+      // 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 = _mm_shuffle_epi32(currentRowSum, _MM_SHUFFLE(3, 3, 3, 3));
+
+      __m128i sumPixels = AccumulatePixelSums(_mm_unpacklo_epi16(
+          _mm_unpacklo_epi8(_mm_set1_epi32(pixels), _mm_setzero_si128()),
+          _mm_setzero_si128()));
+      sumPixels = _mm_add_epi32(sumPixels, currentRowSum);
+
+      currentRowSum = sumPixels;
+
+      _mm_store_si128(
+          (__m128i*)(intRow + x),
+          _mm_add_epi32(sumPixels, _mm_load_si128((__m128i*)(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*)&currentRowSum)[(aSize.width % 4) - 1];
+      for (; x < integralImageSize.width; x++) {
+        // We could be unaligned here!
+        if (!(x & 3)) {
+          // aligned!
+          currentRowSum = _mm_set1_epi32(intCurrentRowSum);
+          break;
+        }
+        intCurrentRowSum += pixel;
+        intRow[x] = intPrevRow[x] + intCurrentRowSum;
+      }
+    } else {
+      currentRowSum = _mm_shuffle_epi32(currentRowSum, _MM_SHUFFLE(3, 3, 3, 3));
+    }
+    for (; x < integralImageSize.width; x += 4) {
+      __m128i sumPixels = AccumulatePixelSums(_mm_set1_epi32(pixel));
+
+      sumPixels = _mm_add_epi32(sumPixels, currentRowSum);
+
+      currentRowSum = _mm_shuffle_epi32(sumPixels, _MM_SHUFFLE(3, 3, 3, 3));
+
+      _mm_store_si128(
+          (__m128i*)(intRow + x),
+          _mm_add_epi32(sumPixels, _mm_load_si128((__m128i*)(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++) {
+      __m128i* intRow = (__m128i*)(aIntegralImage + (y * stride32bit));
+      __m128i* intPrevRow = (__m128i*)(aIntegralImage + (y - 1) * stride32bit);
+      __m128i* intLastRow =
+          (__m128i*)(aIntegralImage +
+                     (integralImageSize.height - 1) * stride32bit);
+
+      for (int x = 0; x < integralImageSize.width; x += 4) {
+        _mm_store_si128(intRow + (x / 4),
+                        _mm_add_epi32(_mm_load_si128(intLastRow + (x / 4)),
+                                      _mm_load_si128(intPrevRow + (x / 4))));
+      }
+    }
+  }
+}
+
+/**
+ * Attempt to do an in-place box blur using an integral image.
+ */
+void AlphaBoxBlur::BoxBlur_SSE2(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_SSE2(leftInflation, aRightLobe, aTopLobe, aBottomLobe,
+                             aIntegralImage, aIntegralImageStride, aData,
+                             mStride, size);
+
+  __m128i divisor = _mm_set1_epi32(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++) {
+    // Not using ContainsY(y) because we do not skip y == skipRect.Y()
+    // although that may not be done on purpose
+    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) {
+      // Not using ContainsX(x) because we do not skip x == skipRect.X()
+      // although that may not be done on purpose
+      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;
+      }
+
+      __m128i topLeft;
+      __m128i topRight;
+      __m128i bottomRight;
+      __m128i bottomLeft;
+
+      topLeft = loadUnaligned128((__m128i*)(topLeftBase + x));
+      topRight = loadUnaligned128((__m128i*)(topRightBase + x));
+      bottomRight = loadUnaligned128((__m128i*)(bottomRightBase + x));
+      bottomLeft = loadUnaligned128((__m128i*)(bottomLeftBase + x));
+      __m128i result1 =
+          BlurFourPixels(topLeft, topRight, bottomRight, bottomLeft, divisor);
+
+      topLeft = loadUnaligned128((__m128i*)(topLeftBase + x + 4));
+      topRight = loadUnaligned128((__m128i*)(topRightBase + x + 4));
+      bottomRight = loadUnaligned128((__m128i*)(bottomRightBase + x + 4));
+      bottomLeft = loadUnaligned128((__m128i*)(bottomLeftBase + x + 4));
+      __m128i result2 =
+          BlurFourPixels(topLeft, topRight, bottomRight, bottomLeft, divisor);
+
+      topLeft = loadUnaligned128((__m128i*)(topLeftBase + x + 8));
+      topRight = loadUnaligned128((__m128i*)(topRightBase + x + 8));
+      bottomRight = loadUnaligned128((__m128i*)(bottomRightBase + x + 8));
+      bottomLeft = loadUnaligned128((__m128i*)(bottomLeftBase + x + 8));
+      __m128i result3 =
+          BlurFourPixels(topLeft, topRight, bottomRight, bottomLeft, divisor);
+
+      topLeft = loadUnaligned128((__m128i*)(topLeftBase + x + 12));
+      topRight = loadUnaligned128((__m128i*)(topRightBase + x + 12));
+      bottomRight = loadUnaligned128((__m128i*)(bottomRightBase + x + 12));
+      bottomLeft = loadUnaligned128((__m128i*)(bottomLeftBase + x + 12));
+      __m128i result4 =
+          BlurFourPixels(topLeft, topRight, bottomRight, bottomLeft, divisor);
+
+      __m128i final = _mm_packus_epi16(_mm_packs_epi32(result1, result2),
+                                       _mm_packs_epi32(result3, result4));
+
+      _mm_storeu_si128((__m128i*)(data + stride * y + x), final);
+    }
+
+    // Process the remaining pixels 4 bytes at a time.
+    for (; x < size.width; x += 4) {
+      // Not using Containsx(x) because we do not skip x == skipRect.X()
+      // although that may not be done on purpose
+      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;
+      }
+      __m128i topLeft = loadUnaligned128((__m128i*)(topLeftBase + x));
+      __m128i topRight = loadUnaligned128((__m128i*)(topRightBase + x));
+      __m128i bottomRight = loadUnaligned128((__m128i*)(bottomRightBase + x));
+      __m128i bottomLeft = loadUnaligned128((__m128i*)(bottomLeftBase + x));
+
+      __m128i result =
+          BlurFourPixels(topLeft, topRight, bottomRight, bottomLeft, divisor);
+      __m128i final = _mm_packus_epi16(
+          _mm_packs_epi32(result, _mm_setzero_si128()), _mm_setzero_si128());
+
+      *(uint32_t*)(data + stride * y + x) = _mm_cvtsi128_si32(final);
+    }
+  }
+}
+
+}  // namespace mozilla::gfx