diff --git a/Aaru6.Checksums/Aaru6.Checksums.csproj b/Aaru6.Checksums/Aaru6.Checksums.csproj
index c665861..bc3e4fd 100644
--- a/Aaru6.Checksums/Aaru6.Checksums.csproj
+++ b/Aaru6.Checksums/Aaru6.Checksums.csproj
@@ -53,6 +53,7 @@
+
diff --git a/Aaru6.Checksums/Adler32/neon.cs b/Aaru6.Checksums/Adler32/neon.cs
new file mode 100644
index 0000000..7e1d625
--- /dev/null
+++ b/Aaru6.Checksums/Adler32/neon.cs
@@ -0,0 +1,224 @@
+// /***************************************************************************
+// Aaru Data Preservation Suite
+// ----------------------------------------------------------------------------
+//
+// Filename : neon.cs
+// Author(s) : Natalia Portillo
+// The Chromium Authors
+//
+// Component : Checksums.
+//
+// --[ Description ] ----------------------------------------------------------
+//
+// Compute Adler32 checksum using NEON vectorization.
+//
+// --[ License ] --------------------------------------------------------------
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * 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.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// 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
+// OWNER 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.
+//
+// ----------------------------------------------------------------------------
+// Copyright © 2011-2021 Natalia Portillo
+// Copyright 2017 The Chromium Authors. All rights reserved.
+// ****************************************************************************/
+
+using System.Runtime.Intrinsics;
+using System.Runtime.Intrinsics.Arm;
+
+namespace Aaru6.Checksums.Adler32
+{
+ internal static class neon
+ {
+ internal static void Step(ref ushort preSum1, ref ushort preSum2, byte[] buf, uint len)
+ {
+ /*
+ * Split Adler-32 into component sums.
+ */
+ uint s1 = preSum1;
+ uint s2 = preSum2;
+
+ int bufPos = 0;
+
+ /*
+ * Process the data in blocks.
+ */
+ uint BLOCK_SIZE = 1 << 5;
+ uint blocks = len / BLOCK_SIZE;
+ len -= blocks * BLOCK_SIZE;
+
+ while(blocks != 0)
+ {
+ uint n = Adler32Context.NMAX / BLOCK_SIZE; /* The NMAX constraint. */
+
+ if(n > blocks)
+ n = blocks;
+
+ blocks -= n;
+ /*
+ * Process n blocks of data. At most NMAX data bytes can be
+ * processed before s2 must be reduced modulo ADLER_MODULE.
+ */
+ Vector128 v_s2 = Vector128.Create(s1 * n, 0, 0, 0);
+ Vector128 v_s1 = Vector128.Create(0u, 0, 0, 0);
+ Vector128 v_column_sum_1 = AdvSimd.DuplicateToVector128((ushort)0);
+ Vector128 v_column_sum_2 = AdvSimd.DuplicateToVector128((ushort)0);
+ Vector128 v_column_sum_3 = AdvSimd.DuplicateToVector128((ushort)0);
+ Vector128 v_column_sum_4 = AdvSimd.DuplicateToVector128((ushort)0);
+
+ do
+ {
+ /*
+ * Load 32 input bytes.
+ */
+ Vector128 bytes1 = Vector128.Create(buf[bufPos], buf[bufPos + 1], buf[bufPos + 2],
+ buf[bufPos + 3], buf[bufPos + 4], buf[bufPos + 5],
+ buf[bufPos + 6], buf[bufPos + 7], buf[bufPos + 8],
+ buf[bufPos + 9], buf[bufPos + 10], buf[bufPos + 11],
+ buf[bufPos + 12], buf[bufPos + 13], buf[bufPos + 14],
+ buf[bufPos + 15]);
+
+ bufPos += 16;
+
+ Vector128 bytes2 = Vector128.Create(buf[bufPos], buf[bufPos + 1], buf[bufPos + 2],
+ buf[bufPos + 3], buf[bufPos + 4], buf[bufPos + 5],
+ buf[bufPos + 6], buf[bufPos + 7], buf[bufPos + 8],
+ buf[bufPos + 9], buf[bufPos + 10], buf[bufPos + 11],
+ buf[bufPos + 12], buf[bufPos + 13], buf[bufPos + 14],
+ buf[bufPos + 15]);
+
+ bufPos += 16;
+ /*
+ * Add previous block byte sum to v_s2.
+ */
+ v_s2 = AdvSimd.Add(v_s2, v_s1);
+
+ /*
+ * Horizontally add the bytes for s1.
+ */
+ v_s1 =
+ AdvSimd.AddPairwiseWideningAndAdd(v_s1,
+ AdvSimd.
+ AddPairwiseWideningAndAdd(AdvSimd.AddPairwiseWidening(bytes1),
+ bytes2));
+
+ /*
+ * Vertically add the bytes for s2.
+ */
+ v_column_sum_1 = AdvSimd.AddWideningLower(v_column_sum_1, bytes1.GetLower());
+ v_column_sum_2 = AdvSimd.AddWideningLower(v_column_sum_2, bytes1.GetUpper());
+ v_column_sum_3 = AdvSimd.AddWideningLower(v_column_sum_3, bytes2.GetLower());
+ v_column_sum_4 = AdvSimd.AddWideningLower(v_column_sum_4, bytes2.GetUpper());
+ } while(--n != 0);
+
+ v_s2 = AdvSimd.ShiftLeftLogical(v_s2, 5);
+
+ /*
+ * Multiply-add bytes by [ 32, 31, 30, ... ] for s2.
+ */
+ v_s2 = AdvSimd.MultiplyWideningLowerAndAdd(v_s2, v_column_sum_1.GetLower(),
+ Vector64.Create((ushort)32, 31, 30, 29));
+
+ v_s2 = AdvSimd.MultiplyWideningLowerAndAdd(v_s2, v_column_sum_1.GetUpper(),
+ Vector64.Create((ushort)28, 27, 26, 25));
+
+ v_s2 = AdvSimd.MultiplyWideningLowerAndAdd(v_s2, v_column_sum_2.GetLower(),
+ Vector64.Create((ushort)24, 23, 22, 21));
+
+ v_s2 = AdvSimd.MultiplyWideningLowerAndAdd(v_s2, v_column_sum_2.GetUpper(),
+ Vector64.Create((ushort)20, 19, 18, 17));
+
+ v_s2 = AdvSimd.MultiplyWideningLowerAndAdd(v_s2, v_column_sum_3.GetLower(),
+ Vector64.Create((ushort)16, 15, 14, 13));
+
+ v_s2 = AdvSimd.MultiplyWideningLowerAndAdd(v_s2, v_column_sum_3.GetUpper(),
+ Vector64.Create((ushort)12, 11, 10, 9));
+
+ v_s2 = AdvSimd.MultiplyWideningLowerAndAdd(v_s2, v_column_sum_4.GetLower(),
+ Vector64.Create((ushort)8, 7, 6, 5));
+
+ v_s2 = AdvSimd.MultiplyWideningLowerAndAdd(v_s2, v_column_sum_4.GetUpper(),
+ Vector64.Create((ushort)4, 3, 2, 1));
+
+ /*
+ * Sum epi32 ints v_s1(s2) and accumulate in s1(s2).
+ */
+ Vector64 sum1 = AdvSimd.AddPairwise(v_s1.GetLower(), v_s1.GetUpper());
+ Vector64 sum2 = AdvSimd.AddPairwise(v_s2.GetLower(), v_s2.GetUpper());
+ Vector64 s1s2 = AdvSimd.AddPairwise(sum1, sum2);
+ s1 += AdvSimd.Extract(s1s2, 0);
+ s2 += AdvSimd.Extract(s1s2, 1);
+ /*
+ * Reduce.
+ */
+ s1 %= Adler32Context.ADLER_MODULE;
+ s2 %= Adler32Context.ADLER_MODULE;
+ }
+
+ /*
+ * Handle leftover data.
+ */
+ if(len != 0)
+ {
+ if(len >= 16)
+ {
+ s2 += s1 += buf[bufPos++];
+ s2 += s1 += buf[bufPos++];
+ s2 += s1 += buf[bufPos++];
+ s2 += s1 += buf[bufPos++];
+ s2 += s1 += buf[bufPos++];
+ s2 += s1 += buf[bufPos++];
+ s2 += s1 += buf[bufPos++];
+ s2 += s1 += buf[bufPos++];
+ s2 += s1 += buf[bufPos++];
+ s2 += s1 += buf[bufPos++];
+ s2 += s1 += buf[bufPos++];
+ s2 += s1 += buf[bufPos++];
+ s2 += s1 += buf[bufPos++];
+ s2 += s1 += buf[bufPos++];
+ s2 += s1 += buf[bufPos++];
+ s2 += s1 += buf[bufPos++];
+ len -= 16;
+ }
+
+ while(len-- != 0)
+ {
+ s2 += s1 += buf[bufPos++];
+ }
+
+ if(s1 >= Adler32Context.ADLER_MODULE)
+ s1 -= Adler32Context.ADLER_MODULE;
+
+ s2 %= Adler32Context.ADLER_MODULE;
+ }
+
+ /*
+ * Return the recombined sums.
+ */
+ preSum1 = (ushort)(s1 & 0xFFFF);
+ preSum2 = (ushort)(s2 & 0xFFFF);
+ }
+ }
+}
\ No newline at end of file
diff --git a/Aaru6.Checksums/Adler32Context.cs b/Aaru6.Checksums/Adler32Context.cs
index 648633d..b3b0e6a 100644
--- a/Aaru6.Checksums/Adler32Context.cs
+++ b/Aaru6.Checksums/Adler32Context.cs
@@ -31,6 +31,7 @@
// ****************************************************************************/
using System.IO;
+using System.Runtime.Intrinsics.Arm;
using System.Runtime.Intrinsics.X86;
using System.Text;
using Aaru.CommonTypes.Interfaces;
@@ -96,6 +97,13 @@ namespace Aaru6.Checksums
return;
}
+ if(AdvSimd.IsSupported)
+ {
+ neon.Step(ref preSum1, ref preSum2, data, len);
+
+ return;
+ }
+
uint sum1 = preSum1;
uint sum2 = preSum2;
uint n;