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Diffstat (limited to 'gfx/2d/SwizzleNEON.cpp')
-rw-r--r-- | gfx/2d/SwizzleNEON.cpp | 451 |
1 files changed, 451 insertions, 0 deletions
diff --git a/gfx/2d/SwizzleNEON.cpp b/gfx/2d/SwizzleNEON.cpp new file mode 100644 index 0000000000..887e93d632 --- /dev/null +++ b/gfx/2d/SwizzleNEON.cpp @@ -0,0 +1,451 @@ +/* -*- 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 "Swizzle.h" + +#include <arm_neon.h> + +namespace mozilla { +namespace gfx { + +// Load 1-3 pixels into a 4 pixel vector. +static MOZ_ALWAYS_INLINE uint16x8_t LoadRemainder_NEON(const uint8_t* aSrc, + size_t aLength) { + const uint32_t* src32 = reinterpret_cast<const uint32_t*>(aSrc); + uint32x4_t dst32; + if (aLength >= 2) { + // Load first 2 pixels + dst32 = vcombine_u32(vld1_u32(src32), vdup_n_u32(0)); + // Load third pixel + if (aLength >= 3) { + dst32 = vld1q_lane_u32(src32 + 2, dst32, 2); + } + } else { + // Load single pixel + dst32 = vld1q_lane_u32(src32, vdupq_n_u32(0), 0); + } + return vreinterpretq_u16_u32(dst32); +} + +// Store 1-3 pixels from a vector into memory without overwriting. +static MOZ_ALWAYS_INLINE void StoreRemainder_NEON(uint8_t* aDst, size_t aLength, + const uint16x8_t& aSrc) { + uint32_t* dst32 = reinterpret_cast<uint32_t*>(aDst); + uint32x4_t src32 = vreinterpretq_u32_u16(aSrc); + if (aLength >= 2) { + // Store first 2 pixels + vst1_u32(dst32, vget_low_u32(src32)); + // Store third pixel + if (aLength >= 3) { + vst1q_lane_u32(dst32 + 2, src32, 2); + } + } else { + // Store single pixel + vst1q_lane_u32(dst32, src32, 0); + } +} + +// Premultiply vector of 4 pixels using splayed math. +template <bool aSwapRB, bool aOpaqueAlpha> +static MOZ_ALWAYS_INLINE uint16x8_t +PremultiplyVector_NEON(const uint16x8_t& aSrc) { + // Isolate R and B with mask. + const uint16x8_t mask = vdupq_n_u16(0x00FF); + uint16x8_t rb = vandq_u16(aSrc, mask); + // Swap R and B if necessary. + if (aSwapRB) { + rb = vrev32q_u16(rb); + } + // Isolate G and A by shifting down to bottom of word. + uint16x8_t ga = vshrq_n_u16(aSrc, 8); + + // Duplicate alphas to get vector of A1 A1 A2 A2 A3 A3 A4 A4 + uint16x8_t alphas = vtrnq_u16(ga, ga).val[1]; + + // rb = rb*a + 255; rb += rb >> 8; + rb = vmlaq_u16(mask, rb, alphas); + rb = vsraq_n_u16(rb, rb, 8); + + // If format is not opaque, force A to 255 so that A*alpha/255 = alpha + if (!aOpaqueAlpha) { + ga = vorrq_u16(ga, vreinterpretq_u16_u32(vdupq_n_u32(0x00FF0000))); + } + // ga = ga*a + 255; ga += ga >> 8; + ga = vmlaq_u16(mask, ga, alphas); + ga = vsraq_n_u16(ga, ga, 8); + // If format is opaque, force output A to be 255. + if (aOpaqueAlpha) { + ga = vorrq_u16(ga, vreinterpretq_u16_u32(vdupq_n_u32(0xFF000000))); + } + + // Combine back to final pixel with (rb >> 8) | (ga & 0xFF00FF00) + return vsriq_n_u16(ga, rb, 8); +} + +template <bool aSwapRB, bool aOpaqueAlpha> +static MOZ_ALWAYS_INLINE void PremultiplyChunk_NEON(const uint8_t*& aSrc, + uint8_t*& aDst, + int32_t aAlignedRow, + int32_t aRemainder) { + // Process all 4-pixel chunks as one vector. + for (const uint8_t* end = aSrc + aAlignedRow; aSrc < end;) { + uint16x8_t px = vld1q_u16(reinterpret_cast<const uint16_t*>(aSrc)); + px = PremultiplyVector_NEON<aSwapRB, aOpaqueAlpha>(px); + vst1q_u16(reinterpret_cast<uint16_t*>(aDst), px); + aSrc += 4 * 4; + aDst += 4 * 4; + } + + // Handle any 1-3 remaining pixels. + if (aRemainder) { + uint16x8_t px = LoadRemainder_NEON(aSrc, aRemainder); + px = PremultiplyVector_NEON<aSwapRB, aOpaqueAlpha>(px); + StoreRemainder_NEON(aDst, aRemainder, px); + } +} + +template <bool aSwapRB, bool aOpaqueAlpha> +void PremultiplyRow_NEON(const uint8_t* aSrc, uint8_t* aDst, int32_t aLength) { + int32_t alignedRow = 4 * (aLength & ~3); + int32_t remainder = aLength & 3; + PremultiplyChunk_NEON<aSwapRB, aOpaqueAlpha>(aSrc, aDst, alignedRow, + remainder); +} + +template <bool aSwapRB, bool aOpaqueAlpha> +void Premultiply_NEON(const uint8_t* aSrc, int32_t aSrcGap, uint8_t* aDst, + int32_t aDstGap, IntSize aSize) { + int32_t alignedRow = 4 * (aSize.width & ~3); + int32_t remainder = aSize.width & 3; + // Fold remainder into stride gap. + aSrcGap += 4 * remainder; + aDstGap += 4 * remainder; + + for (int32_t height = aSize.height; height > 0; height--) { + PremultiplyChunk_NEON<aSwapRB, aOpaqueAlpha>(aSrc, aDst, alignedRow, + remainder); + aSrc += aSrcGap; + aDst += aDstGap; + } +} + +// Force instantiation of premultiply variants here. +template void PremultiplyRow_NEON<false, false>(const uint8_t*, uint8_t*, + int32_t); +template void PremultiplyRow_NEON<false, true>(const uint8_t*, uint8_t*, + int32_t); +template void PremultiplyRow_NEON<true, false>(const uint8_t*, uint8_t*, + int32_t); +template void PremultiplyRow_NEON<true, true>(const uint8_t*, uint8_t*, + int32_t); +template void Premultiply_NEON<false, false>(const uint8_t*, int32_t, uint8_t*, + int32_t, IntSize); +template void Premultiply_NEON<false, true>(const uint8_t*, int32_t, uint8_t*, + int32_t, IntSize); +template void Premultiply_NEON<true, false>(const uint8_t*, int32_t, uint8_t*, + int32_t, IntSize); +template void Premultiply_NEON<true, true>(const uint8_t*, int32_t, uint8_t*, + int32_t, IntSize); + +// This generates a table of fixed-point reciprocals representing 1/alpha +// similar to the fallback implementation. However, the reciprocal must +// ultimately be multiplied as an unsigned 9 bit upper part and a signed +// 15 bit lower part to cheaply multiply. Thus, the lower 15 bits of the +// reciprocal is stored 15 bits of the reciprocal are masked off and +// stored in the low word. The upper 9 bits are masked and shifted to fit +// into the high word. These then get independently multiplied with the +// color component and recombined to provide the full recriprocal multiply. +#define UNPREMULQ_NEON(x) \ + ((((0xFF00FFU / (x)) & 0xFF8000U) << 1) | ((0xFF00FFU / (x)) & 0x7FFFU)) +#define UNPREMULQ_NEON_2(x) UNPREMULQ_NEON(x), UNPREMULQ_NEON((x) + 1) +#define UNPREMULQ_NEON_4(x) UNPREMULQ_NEON_2(x), UNPREMULQ_NEON_2((x) + 2) +#define UNPREMULQ_NEON_8(x) UNPREMULQ_NEON_4(x), UNPREMULQ_NEON_4((x) + 4) +#define UNPREMULQ_NEON_16(x) UNPREMULQ_NEON_8(x), UNPREMULQ_NEON_8((x) + 8) +#define UNPREMULQ_NEON_32(x) UNPREMULQ_NEON_16(x), UNPREMULQ_NEON_16((x) + 16) +static const uint32_t sUnpremultiplyTable_NEON[256] = {0, + UNPREMULQ_NEON(1), + UNPREMULQ_NEON_2(2), + UNPREMULQ_NEON_4(4), + UNPREMULQ_NEON_8(8), + UNPREMULQ_NEON_16(16), + UNPREMULQ_NEON_32(32), + UNPREMULQ_NEON_32(64), + UNPREMULQ_NEON_32(96), + UNPREMULQ_NEON_32(128), + UNPREMULQ_NEON_32(160), + UNPREMULQ_NEON_32(192), + UNPREMULQ_NEON_32(224)}; + +// Unpremultiply a vector of 4 pixels using splayed math and a reciprocal table +// that avoids doing any actual division. +template <bool aSwapRB> +static MOZ_ALWAYS_INLINE uint16x8_t +UnpremultiplyVector_NEON(const uint16x8_t& aSrc) { + // Isolate R and B with mask. + uint16x8_t rb = vandq_u16(aSrc, vdupq_n_u16(0x00FF)); + // Swap R and B if necessary. + if (aSwapRB) { + rb = vrev32q_u16(rb); + } + + // Isolate G and A by shifting down to bottom of word. + uint16x8_t ga = vshrq_n_u16(aSrc, 8); + // Extract the alphas for the 4 pixels from the now isolated words. + int a1 = vgetq_lane_u16(ga, 1); + int a2 = vgetq_lane_u16(ga, 3); + int a3 = vgetq_lane_u16(ga, 5); + int a4 = vgetq_lane_u16(ga, 7); + + // First load all of the interleaved low and high portions of the reciprocals + // and combine them a single vector as lo1 hi1 lo2 hi2 lo3 hi3 lo4 hi4 + uint16x8_t q1234 = vreinterpretq_u16_u32(vld1q_lane_u32( + &sUnpremultiplyTable_NEON[a4], + vld1q_lane_u32( + &sUnpremultiplyTable_NEON[a3], + vld1q_lane_u32( + &sUnpremultiplyTable_NEON[a2], + vld1q_lane_u32(&sUnpremultiplyTable_NEON[a1], vdupq_n_u32(0), 0), + 1), + 2), + 3)); + // Transpose the interleaved low/high portions so that we produce + // two separate duplicated vectors for the low and high portions respectively: + // lo1 lo1 lo2 lo2 lo3 lo3 lo4 lo4 and hi1 hi1 hi2 hi2 hi3 hi3 hi4 hi4 + uint16x8x2_t q1234lohi = vtrnq_u16(q1234, q1234); + + // VQDMULH is a signed multiply that doubles (*2) the result, then takes the + // high word. To work around the signedness and the doubling, the low + // portion of the reciprocal only stores the lower 15 bits, which fits in a + // signed 16 bit integer. The high 9 bit portion is effectively also doubled + // by 2 as a side-effect of being shifted for storage. Thus the output scale + // of doing a normal multiply by the high portion and the VQDMULH by the low + // portion are both doubled and can be safely added together. The resulting + // sum just needs to be halved (via VHADD) to thus cancel out the doubling. + // All this combines to produce a reciprocal multiply of the form: + // rb = ((rb * hi) + ((rb * lo * 2) >> 16)) / 2 + rb = vhaddq_u16( + vmulq_u16(rb, q1234lohi.val[1]), + vreinterpretq_u16_s16(vqdmulhq_s16( + vreinterpretq_s16_u16(rb), vreinterpretq_s16_u16(q1234lohi.val[0])))); + + // ga = ((ga * hi) + ((ga * lo * 2) >> 16)) / 2 + ga = vhaddq_u16( + vmulq_u16(ga, q1234lohi.val[1]), + vreinterpretq_u16_s16(vqdmulhq_s16( + vreinterpretq_s16_u16(ga), vreinterpretq_s16_u16(q1234lohi.val[0])))); + + // Combine to the final pixel with ((rb | (ga << 8)) & ~0xFF000000) | (aSrc & + // 0xFF000000), which inserts back in the original alpha value unchanged. + return vbslq_u16(vreinterpretq_u16_u32(vdupq_n_u32(0xFF000000)), aSrc, + vsliq_n_u16(rb, ga, 8)); +} + +template <bool aSwapRB> +static MOZ_ALWAYS_INLINE void UnpremultiplyChunk_NEON(const uint8_t*& aSrc, + uint8_t*& aDst, + int32_t aAlignedRow, + int32_t aRemainder) { + // Process all 4-pixel chunks as one vector. + for (const uint8_t* end = aSrc + aAlignedRow; aSrc < end;) { + uint16x8_t px = vld1q_u16(reinterpret_cast<const uint16_t*>(aSrc)); + px = UnpremultiplyVector_NEON<aSwapRB>(px); + vst1q_u16(reinterpret_cast<uint16_t*>(aDst), px); + aSrc += 4 * 4; + aDst += 4 * 4; + } + + // Handle any 1-3 remaining pixels. + if (aRemainder) { + uint16x8_t px = LoadRemainder_NEON(aSrc, aRemainder); + px = UnpremultiplyVector_NEON<aSwapRB>(px); + StoreRemainder_NEON(aDst, aRemainder, px); + } +} + +template <bool aSwapRB> +void UnpremultiplyRow_NEON(const uint8_t* aSrc, uint8_t* aDst, + int32_t aLength) { + int32_t alignedRow = 4 * (aLength & ~3); + int32_t remainder = aLength & 3; + UnpremultiplyChunk_NEON<aSwapRB>(aSrc, aDst, alignedRow, remainder); +} + +template <bool aSwapRB> +void Unpremultiply_NEON(const uint8_t* aSrc, int32_t aSrcGap, uint8_t* aDst, + int32_t aDstGap, IntSize aSize) { + int32_t alignedRow = 4 * (aSize.width & ~3); + int32_t remainder = aSize.width & 3; + // Fold remainder into stride gap. + aSrcGap += 4 * remainder; + aDstGap += 4 * remainder; + + for (int32_t height = aSize.height; height > 0; height--) { + UnpremultiplyChunk_NEON<aSwapRB>(aSrc, aDst, alignedRow, remainder); + aSrc += aSrcGap; + aDst += aDstGap; + } +} + +// Force instantiation of unpremultiply variants here. +template void UnpremultiplyRow_NEON<false>(const uint8_t*, uint8_t*, int32_t); +template void UnpremultiplyRow_NEON<true>(const uint8_t*, uint8_t*, int32_t); +template void Unpremultiply_NEON<false>(const uint8_t*, int32_t, uint8_t*, + int32_t, IntSize); +template void Unpremultiply_NEON<true>(const uint8_t*, int32_t, uint8_t*, + int32_t, IntSize); + +// Swizzle a vector of 4 pixels providing swaps and opaquifying. +template <bool aSwapRB, bool aOpaqueAlpha> +static MOZ_ALWAYS_INLINE uint16x8_t SwizzleVector_NEON(const uint16x8_t& aSrc) { + // Swap R and B, then add to G and A (forced to 255): + // (((src>>16) | (src << 16)) & 0x00FF00FF) | + // ((src | 0xFF000000) & ~0x00FF00FF) + return vbslq_u16( + vdupq_n_u16(0x00FF), vrev32q_u16(aSrc), + aOpaqueAlpha + ? vorrq_u16(aSrc, vreinterpretq_u16_u32(vdupq_n_u32(0xFF000000))) + : aSrc); +} + +#if 0 +// These specializations currently do not profile faster than the generic versions, +// so disable them for now. + +// Optimized implementations for when there is no R and B swap. +template<> +static MOZ_ALWAYS_INLINE uint16x8_t +SwizzleVector_NEON<false, true>(const uint16x8_t& aSrc) +{ + // Force alpha to 255. + return vorrq_u16(aSrc, vreinterpretq_u16_u32(vdupq_n_u32(0xFF000000))); +} + +template<> +static MOZ_ALWAYS_INLINE uint16x8_t +SwizzleVector_NEON<false, false>(const uint16x8_t& aSrc) +{ + return aSrc; +} +#endif + +template <bool aSwapRB, bool aOpaqueAlpha> +static MOZ_ALWAYS_INLINE void SwizzleChunk_NEON(const uint8_t*& aSrc, + uint8_t*& aDst, + int32_t aAlignedRow, + int32_t aRemainder) { + // Process all 4-pixel chunks as one vector. + for (const uint8_t* end = aSrc + aAlignedRow; aSrc < end;) { + uint16x8_t px = vld1q_u16(reinterpret_cast<const uint16_t*>(aSrc)); + px = SwizzleVector_NEON<aSwapRB, aOpaqueAlpha>(px); + vst1q_u16(reinterpret_cast<uint16_t*>(aDst), px); + aSrc += 4 * 4; + aDst += 4 * 4; + } + + // Handle any 1-3 remaining pixels. + if (aRemainder) { + uint16x8_t px = LoadRemainder_NEON(aSrc, aRemainder); + px = SwizzleVector_NEON<aSwapRB, aOpaqueAlpha>(px); + StoreRemainder_NEON(aDst, aRemainder, px); + } +} + +template <bool aSwapRB, bool aOpaqueAlpha> +void SwizzleRow_NEON(const uint8_t* aSrc, uint8_t* aDst, int32_t aLength) { + int32_t alignedRow = 4 * (aLength & ~3); + int32_t remainder = aLength & 3; + SwizzleChunk_NEON<aSwapRB, aOpaqueAlpha>(aSrc, aDst, alignedRow, remainder); +} + +template <bool aSwapRB, bool aOpaqueAlpha> +void Swizzle_NEON(const uint8_t* aSrc, int32_t aSrcGap, uint8_t* aDst, + int32_t aDstGap, IntSize aSize) { + int32_t alignedRow = 4 * (aSize.width & ~3); + int32_t remainder = aSize.width & 3; + // Fold remainder into stride gap. + aSrcGap += 4 * remainder; + aDstGap += 4 * remainder; + + for (int32_t height = aSize.height; height > 0; height--) { + SwizzleChunk_NEON<aSwapRB, aOpaqueAlpha>(aSrc, aDst, alignedRow, remainder); + aSrc += aSrcGap; + aDst += aDstGap; + } +} + +// Force instantiation of swizzle variants here. +template void SwizzleRow_NEON<true, false>(const uint8_t*, uint8_t*, int32_t); +template void SwizzleRow_NEON<true, true>(const uint8_t*, uint8_t*, int32_t); +template void Swizzle_NEON<true, false>(const uint8_t*, int32_t, uint8_t*, + int32_t, IntSize); +template void Swizzle_NEON<true, true>(const uint8_t*, int32_t, uint8_t*, + int32_t, IntSize); + +template <bool aSwapRB> +void UnpackRowRGB24(const uint8_t* aSrc, uint8_t* aDst, int32_t aLength); + +template <bool aSwapRB> +void UnpackRowRGB24_NEON(const uint8_t* aSrc, uint8_t* aDst, int32_t aLength) { + // Because this implementation will read an additional 4 bytes of data that + // is ignored and masked over, we cannot use the accelerated version for the + // last 1-5 pixels (3-15 bytes remaining) to guarantee we don't access memory + // outside the buffer (we read in 16 byte chunks). + if (aLength < 6) { + UnpackRowRGB24<aSwapRB>(aSrc, aDst, aLength); + return; + } + + // Because we are expanding, we can only process the data back to front in + // case we are performing this in place. + int32_t alignedRow = (aLength - 2) & ~3; + int32_t remainder = aLength - alignedRow; + + const uint8_t* src = aSrc + alignedRow * 3; + uint8_t* dst = aDst + alignedRow * 4; + + // Handle 2-5 remaining pixels. + UnpackRowRGB24<aSwapRB>(src, dst, remainder); + + uint8x8_t masklo; + uint8x8_t maskhi; + if (aSwapRB) { + static const uint8_t masklo_data[] = {2, 1, 0, 0, 5, 4, 3, 0}; + static const uint8_t maskhi_data[] = {4, 3, 2, 0, 7, 6, 5, 0}; + masklo = vld1_u8(masklo_data); + maskhi = vld1_u8(maskhi_data); + } else { + static const uint8_t masklo_data[] = {0, 1, 2, 0, 3, 4, 5, 0}; + static const uint8_t maskhi_data[] = {2, 3, 4, 0, 5, 6, 7, 0}; + masklo = vld1_u8(masklo_data); + maskhi = vld1_u8(maskhi_data); + } + + uint8x16_t alpha = vreinterpretq_u8_u32(vdupq_n_u32(0xFF000000)); + + // Process all 4-pixel chunks as one vector. + src -= 4 * 3; + dst -= 4 * 4; + while (src >= aSrc) { + uint8x16_t px = vld1q_u8(src); + // G2R2B1G1 R1B0G0R0 -> X1R1G1B1 X0R0G0B0 + uint8x8_t pxlo = vtbl1_u8(vget_low_u8(px), masklo); + // B3G3R3B2 G2R2B1G1 -> X3R3G3B3 X2R2G2B2 + uint8x8_t pxhi = + vtbl1_u8(vext_u8(vget_low_u8(px), vget_high_u8(px), 4), maskhi); + px = vcombine_u8(pxlo, pxhi); + px = vorrq_u8(px, alpha); + vst1q_u8(dst, px); + src -= 4 * 3; + dst -= 4 * 4; + } +} + +// Force instantiation of swizzle variants here. +template void UnpackRowRGB24_NEON<false>(const uint8_t*, uint8_t*, int32_t); +template void UnpackRowRGB24_NEON<true>(const uint8_t*, uint8_t*, int32_t); + +} // namespace gfx +} // namespace mozilla |