1 /* 2 * Copyright 2013 The Android Open Source Project 3 * 4 * Use of this source code is governed by a BSD-style license that can be 5 * found in the LICENSE file. 6 */ 7 8 #include <emmintrin.h> 9 #include "SkBitmap.h" 10 #include "SkBlurImage_opts_SSE2.h" 11 #include "SkColorPriv.h" 12 #include "SkRect.h" 13 14 namespace { 15 enum BlurDirection { 16 kX, kY 17 }; 18 19 /* Helper function to spread the components of a 32-bit integer into the 20 * lower 8 bits of each 32-bit element of an SSE register. 21 */ 22 inline __m128i expand(int a) { 23 const __m128i zero = _mm_setzero_si128(); 24 25 // 0 0 0 0 0 0 0 0 0 0 0 0 A R G B 26 __m128i result = _mm_cvtsi32_si128(a); 27 28 // 0 0 0 0 0 0 0 0 0 A 0 R 0 G 0 B 29 result = _mm_unpacklo_epi8(result, zero); 30 31 // 0 0 0 A 0 0 0 R 0 0 0 G 0 0 0 B 32 return _mm_unpacklo_epi16(result, zero); 33 } 34 35 template<BlurDirection srcDirection, BlurDirection dstDirection> 36 void SkBoxBlur_SSE2(const SkPMColor* src, int srcStride, SkPMColor* dst, int kernelSize, 37 int leftOffset, int rightOffset, int width, int height) 38 { 39 const int rightBorder = SkMin32(rightOffset + 1, width); 40 const int srcStrideX = srcDirection == kX ? 1 : srcStride; 41 const int dstStrideX = dstDirection == kX ? 1 : height; 42 const int srcStrideY = srcDirection == kX ? srcStride : 1; 43 const int dstStrideY = dstDirection == kX ? width : 1; 44 const __m128i scale = _mm_set1_epi32((1 << 24) / kernelSize); 45 const __m128i half = _mm_set1_epi32(1 << 23); 46 const __m128i zero = _mm_setzero_si128(); 47 for (int y = 0; y < height; ++y) { 48 __m128i sum = zero; 49 const SkPMColor* p = src; 50 for (int i = 0; i < rightBorder; ++i) { 51 sum = _mm_add_epi32(sum, expand(*p)); 52 p += srcStrideX; 53 } 54 55 const SkPMColor* sptr = src; 56 SkColor* dptr = dst; 57 for (int x = 0; x < width; ++x) { 58 // SSE2 has no PMULLUD, so we must do AG and RB separately. 59 __m128i tmp1 = _mm_mul_epu32(sum, scale); 60 __m128i tmp2 = _mm_mul_epu32(_mm_srli_si128(sum, 4), 61 _mm_srli_si128(scale, 4)); 62 __m128i result = _mm_unpacklo_epi32(_mm_shuffle_epi32(tmp1, _MM_SHUFFLE(0,0,2,0)), 63 _mm_shuffle_epi32(tmp2, _MM_SHUFFLE(0,0,2,0))); 64 65 // sumA*scale+.5 sumB*scale+.5 sumG*scale+.5 sumB*scale+.5 66 result = _mm_add_epi32(result, half); 67 68 // 0 0 0 A 0 0 0 R 0 0 0 G 0 0 0 B 69 result = _mm_srli_epi32(result, 24); 70 71 // 0 0 0 0 0 0 0 0 0 A 0 R 0 G 0 B 72 result = _mm_packs_epi32(result, zero); 73 74 // 0 0 0 0 0 0 0 0 0 0 0 0 A R G B 75 result = _mm_packus_epi16(result, zero); 76 *dptr = _mm_cvtsi128_si32(result); 77 if (x >= leftOffset) { 78 SkColor l = *(sptr - leftOffset * srcStrideX); 79 sum = _mm_sub_epi32(sum, expand(l)); 80 } 81 if (x + rightOffset + 1 < width) { 82 SkColor r = *(sptr + (rightOffset + 1) * srcStrideX); 83 sum = _mm_add_epi32(sum, expand(r)); 84 } 85 sptr += srcStrideX; 86 if (srcDirection == kY) { 87 _mm_prefetch(reinterpret_cast<const char*>(sptr + (rightOffset + 1) * srcStrideX), 88 _MM_HINT_T0); 89 } 90 dptr += dstStrideX; 91 } 92 src += srcStrideY; 93 dst += dstStrideY; 94 } 95 } 96 97 } // namespace 98 99 bool SkBoxBlurGetPlatformProcs_SSE2(SkBoxBlurProc* boxBlurX, 100 SkBoxBlurProc* boxBlurXY, 101 SkBoxBlurProc* boxBlurYX) { 102 *boxBlurX = SkBoxBlur_SSE2<kX, kX>; 103 *boxBlurXY = SkBoxBlur_SSE2<kX, kY>; 104 *boxBlurYX = SkBoxBlur_SSE2<kY, kX>; 105 return true; 106 } 107
