diff --git a/THIRD-PARTY-NOTICES.TXT b/THIRD-PARTY-NOTICES.TXT index 7026e2bc232f7..07a2b94ba5fc6 100644 --- a/THIRD-PARTY-NOTICES.TXT +++ b/THIRD-PARTY-NOTICES.TXT @@ -1297,3 +1297,37 @@ AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + +License notice for Avx512Vbmi base64 encoding / decoding +-------------------------------------------------------- + +Copyright (c) 2015-2018, Wojciech Muła +All rights reserved. + +Redistribution and use in source and binary forms, with or without +modification, are permitted provided that the following conditions are +met: + +1. Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + +2. Redistributions in binary form must reproduce the above copyright + notice, this list of conditions and the following disclaimer in the + documentation and/or other materials provided with the distribution. + +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS +IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED +TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A +PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED +TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR +PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF +LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING +NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS +SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +-------------------------------------------------------- + +Aspects of base64 encoding / decoding are based on algorithm described in "Base64 encoding and decoding at almost the speed of a memory +copy", Wojciech Muła and Daniel Lemire. https://arxiv.org/pdf/1910.05109.pdf diff --git a/src/libraries/System.Private.CoreLib/src/System/Buffers/Text/Base64Decoder.cs b/src/libraries/System.Private.CoreLib/src/System/Buffers/Text/Base64Decoder.cs index 47cf012c0a733..1ad2cf9faa9f3 100644 --- a/src/libraries/System.Private.CoreLib/src/System/Buffers/Text/Base64Decoder.cs +++ b/src/libraries/System.Private.CoreLib/src/System/Buffers/Text/Base64Decoder.cs @@ -68,7 +68,18 @@ private static unsafe OperationStatus DecodeFromUtf8(ReadOnlySpan utf8, Sp if (maxSrcLength >= 24) { - byte* end = srcMax - 45; + byte* end = srcMax - 88; + if (Vector512.IsHardwareAccelerated && Avx512Vbmi.IsSupported && (end >= src)) + { + Avx512Decode(ref src, ref dest, end, maxSrcLength, destLength, srcBytes, destBytes); + + if (src == srcEnd) + { + goto DoneExit; + } + } + + end = srcMax - 45; if (Avx2.IsSupported && (end >= src)) { Avx2Decode(ref src, ref dest, end, maxSrcLength, destLength, srcBytes, destBytes); @@ -616,6 +627,78 @@ private static OperationStatus DecodeWithWhiteSpaceFromUtf8InPlace(Span ut return status; } + [MethodImpl(MethodImplOptions.AggressiveInlining)] + [CompExactlyDependsOn(typeof(Avx512BW))] + [CompExactlyDependsOn(typeof(Avx512Vbmi))] + private static unsafe void Avx512Decode(ref byte* srcBytes, ref byte* destBytes, byte* srcEnd, int sourceLength, int destLength, byte* srcStart, byte* destStart) + { + // Reference for VBMI implementation : https://github.com/WojciechMula/base64simd/tree/master/decode + // If we have AVX512 support, pick off 64 bytes at a time for as long as we can, + // but make sure that we quit before seeing any == markers at the end of the + // string. Also, because we write 16 zeroes at the end of the output, ensure + // that there are at least 22 valid bytes of input data remaining to close the + // gap. 64 + 2 + 22 = 88 bytes. + byte* src = srcBytes; + byte* dest = destBytes; + + // The JIT won't hoist these "constants", so help it + Vector512 vbmiLookup0 = Vector512.Create( + 0x80808080, 0x80808080, 0x80808080, 0x80808080, + 0x80808080, 0x80808080, 0x80808080, 0x80808080, + 0x80808080, 0x80808080, 0x3e808080, 0x3f808080, + 0x37363534, 0x3b3a3938, 0x80803d3c, 0x80808080).AsSByte(); + Vector512 vbmiLookup1 = Vector512.Create( + 0x02010080, 0x06050403, 0x0a090807, 0x0e0d0c0b, + 0x1211100f, 0x16151413, 0x80191817, 0x80808080, + 0x1c1b1a80, 0x201f1e1d, 0x24232221, 0x28272625, + 0x2c2b2a29, 0x302f2e2d, 0x80333231, 0x80808080).AsSByte(); + Vector512 vbmiPackedLanesControl = Vector512.Create( + 0x06000102, 0x090a0405, 0x0c0d0e08, 0x16101112, + 0x191a1415, 0x1c1d1e18, 0x26202122, 0x292a2425, + 0x2c2d2e28, 0x36303132, 0x393a3435, 0x3c3d3e38, + 0x00000000, 0x00000000, 0x00000000, 0x00000000).AsByte(); + + Vector512 mergeConstant0 = Vector512.Create(0x01400140).AsSByte(); + Vector512 mergeConstant1 = Vector512.Create(0x00011000).AsInt16(); + + // This algorithm requires AVX512VBMI support. + // Vbmi was first introduced in CannonLake and is avaialable from IceLake on. + do + { + AssertRead>(src, srcStart, sourceLength); + Vector512 str = Vector512.Load(src).AsSByte(); + + // Step 1: Translate encoded Base64 input to their original indices + // This step also checks for invalid inputs and exits. + // After this, we have indices which are verified to have upper 2 bits set to 0 in each byte. + // origIndex = [...|00dddddd|00cccccc|00bbbbbb|00aaaaaa] + Vector512 origIndex = Avx512Vbmi.PermuteVar64x8x2(vbmiLookup0, str, vbmiLookup1); + Vector512 errorVec = (origIndex.AsInt32() | str.AsInt32()).AsSByte(); + if (errorVec.ExtractMostSignificantBits() != 0) + { + break; + } + + // Step 2: Now we need to reshuffle bits to remove the 0 bits. + // multiAdd1: [...|0000cccc|ccdddddd|0000aaaa|aabbbbbb] + Vector512 multiAdd1 = Avx512BW.MultiplyAddAdjacent(origIndex.AsByte(), mergeConstant0); + // multiAdd1: [...|00000000|aaaaaabb|bbbbcccc|ccdddddd] + Vector512 multiAdd2 = Avx512BW.MultiplyAddAdjacent(multiAdd1, mergeConstant1); + + // Step 3: Pack 48 bytes + str = Avx512Vbmi.PermuteVar64x8(multiAdd2.AsByte(), vbmiPackedLanesControl).AsSByte(); + + AssertWrite>(dest, destStart, destLength); + str.Store((sbyte*)dest); + src += 64; + dest += 48; + } + while (src <= srcEnd); + + srcBytes = src; + destBytes = dest; + } + [MethodImpl(MethodImplOptions.AggressiveInlining)] [CompExactlyDependsOn(typeof(Avx2))] private static unsafe void Avx2Decode(ref byte* srcBytes, ref byte* destBytes, byte* srcEnd, int sourceLength, int destLength, byte* srcStart, byte* destStart) diff --git a/src/libraries/System.Private.CoreLib/src/System/Buffers/Text/Base64Encoder.cs b/src/libraries/System.Private.CoreLib/src/System/Buffers/Text/Base64Encoder.cs index 077dbde6f00e1..08ca62b533f51 100644 --- a/src/libraries/System.Private.CoreLib/src/System/Buffers/Text/Base64Encoder.cs +++ b/src/libraries/System.Private.CoreLib/src/System/Buffers/Text/Base64Encoder.cs @@ -67,7 +67,16 @@ public static unsafe OperationStatus EncodeToUtf8(ReadOnlySpan bytes, Span if (maxSrcLength >= 16) { - byte* end = srcMax - 32; + byte* end = srcMax - 64; + if (Vector512.IsHardwareAccelerated && Avx512Vbmi.IsSupported && (end >= src)) + { + Avx512Encode(ref src, ref dest, end, maxSrcLength, destLength, srcBytes, destBytes); + + if (src == srcEnd) + goto DoneExit; + } + + end = srcMax - 64; if (Avx2.IsSupported && (end >= src)) { Avx2Encode(ref src, ref dest, end, maxSrcLength, destLength, srcBytes, destBytes); @@ -226,6 +235,80 @@ public static unsafe OperationStatus EncodeToUtf8InPlace(Span buffer, int } } + [MethodImpl(MethodImplOptions.AggressiveInlining)] + [CompExactlyDependsOn(typeof(Avx512BW))] + [CompExactlyDependsOn(typeof(Avx512Vbmi))] + private static unsafe void Avx512Encode(ref byte* srcBytes, ref byte* destBytes, byte* srcEnd, int sourceLength, int destLength, byte* srcStart, byte* destStart) + { + // Reference for VBMI implementation : https://github.com/WojciechMula/base64simd/tree/master/encode + // If we have AVX512 support, pick off 48 bytes at a time for as long as we can. + // But because we read 64 bytes at a time, ensure we have enough room to do a + // full 64-byte read without segfaulting. + + byte* src = srcBytes; + byte* dest = destBytes; + + // The JIT won't hoist these "constants", so help it + Vector512 shuffleVecVbmi = Vector512.Create( + 0x01020001, 0x04050304, 0x07080607, 0x0a0b090a, + 0x0d0e0c0d, 0x10110f10, 0x13141213, 0x16171516, + 0x191a1819, 0x1c1d1b1c, 0x1f201e1f, 0x22232122, + 0x25262425, 0x28292728, 0x2b2c2a2b, 0x2e2f2d2e).AsSByte(); + Vector512 vbmiLookup = Vector512.Create("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"u8).AsSByte(); + + Vector512 maskAC = Vector512.Create((uint)0x0fc0fc00).AsUInt16(); + Vector512 maskBB = Vector512.Create((uint)0x3f003f00); + Vector512 shiftAC = Vector512.Create((uint)0x0006000a).AsUInt16(); + Vector512 shiftBB = Vector512.Create((uint)0x00080004).AsUInt16(); + + AssertRead>(src, srcStart, sourceLength); + + // This algorithm requires AVX512VBMI support. + // Vbmi was first introduced in CannonLake and is avaialable from IceLake on. + + // str = [...|PONM|LKJI|HGFE|DCBA] + Vector512 str = Vector512.Load(src).AsSByte(); + + while (true) + { + // Step 1 : Split 48 bytes into 64 bytes with each byte using 6-bits from input + // str = [...|KLJK|HIGH|EFDE|BCAB] + str = Avx512Vbmi.PermuteVar64x8(str, shuffleVecVbmi); + + // TO-DO- This can be achieved faster with multishift + // Consider the first 4 bytes - BCAB + // temp1 = [...|0000cccc|cc000000|aaaaaa00|00000000] + Vector512 temp1 = (str.AsUInt16() & maskAC); + + // temp2 = [...|00000000|00cccccc|00000000|00aaaaaa] + Vector512 temp2 = Avx512BW.ShiftRightLogicalVariable(temp1, shiftAC).AsUInt16(); + + // temp3 = [...|ccdddddd|00000000|aabbbbbb|cccc0000] + Vector512 temp3 = Avx512BW.ShiftLeftLogicalVariable(str.AsUInt16(), shiftBB).AsUInt16(); + + // str = [...|00dddddd|00cccccc|00bbbbbb|00aaaaaa] + str = Vector512.ConditionalSelect(maskBB, temp3.AsUInt32(), temp2.AsUInt32()).AsSByte(); + + // Step 2: Now we have the indices calculated. Next step is to use these indices to translate. + str = Avx512Vbmi.PermuteVar64x8(vbmiLookup, str); + + AssertWrite>(dest, destStart, destLength); + str.Store((sbyte*)dest); + + src += 48; + dest += 64; + + if (src > srcEnd) + break; + + AssertRead>(src, srcStart, sourceLength); + str = Vector512.Load(src).AsSByte(); + } + + srcBytes = src; + destBytes = dest; + } + [MethodImpl(MethodImplOptions.AggressiveInlining)] [CompExactlyDependsOn(typeof(Avx2))] private static unsafe void Avx2Encode(ref byte* srcBytes, ref byte* destBytes, byte* srcEnd, int sourceLength, int destLength, byte* srcStart, byte* destStart)