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leecampbell-codeagentLeeCampbell
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feat(#161): implement tasks
1 parent 43b4cdb commit ddc4c75

8 files changed

Lines changed: 63 additions & 131 deletions

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‎HdrHistogram.Benchmarking/LeadingZeroCount/LeadingZeroCountBenchmarkBase.cs‎

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@@ -53,7 +53,6 @@ public void OneOffValidationOfImplementations()
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var functions = new Dictionary<string, Func<long, int>>
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{
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{"CurrentImpl", Bitwise.NumberOfLeadingZeros},
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{"Imperative", Bitwise.Imperative.NumberOfLeadingZeros},
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{"IfAndShift", LeadingZeroCount.IfAndShift.GetLeadingZeroCount},
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//{"MathLog", LeadingZeroCount.MathLog.GetLeadingZeroCount},
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{"StringManipulation", LeadingZeroCount.StringManipulation.GetLeadingZeroCount},
@@ -121,17 +120,6 @@ public int CurrentImplementation()
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return sum;
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}
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[Benchmark(OperationsPerInvoke = TEST_VALUE_LENGTH)]
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public int ImperativeImplementation()
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{
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var sum = 0;
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for (int i = 0; i < _testValues.Length; i++)
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{
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sum += Bitwise.Imperative.NumberOfLeadingZeros(_testValues[i]);
131-
}
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return sum;
133-
}
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[Benchmark(OperationsPerInvoke = TEST_VALUE_LENGTH)]
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public int IfAndShift()
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{

‎HdrHistogram.UnitTests/Utilities/BitwiseTests.cs‎

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/*
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* This is a .NET port of the original Java version, which was written by
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* Gil Tene as described in
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* https://github.com/HdrHistogram/HdrHistogram
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* and released to the public domain, as explained at
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* http://creativecommons.org/publicdomain/zero/1.0/
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*/
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using HdrHistogram.Utilities;
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using Xunit;
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namespace HdrHistogram.UnitTests.Utilities
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{
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public class BitwiseTests
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{
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[Theory]
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[InlineData(0L, 64)]
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[InlineData(1L, 63)]
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[InlineData(2L, 62)]
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[InlineData(4L, 61)]
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[InlineData(8L, 60)]
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[InlineData(16L, 59)]
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[InlineData(32L, 58)]
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[InlineData(64L, 57)]
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[InlineData(128L, 56)]
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[InlineData(256L, 55)]
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[InlineData(512L, 54)]
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[InlineData(1024L, 53)]
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[InlineData(2048L, 52)]
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[InlineData(4096L, 51)]
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[InlineData(8192L, 50)]
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[InlineData(16384L, 49)]
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[InlineData(32768L, 48)]
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[InlineData(65536L, 47)]
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[InlineData(1L << 30, 33)]
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[InlineData(1L << 31, 32)]
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[InlineData(1L << 32, 31)]
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[InlineData(1L << 62, 1)]
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[InlineData(long.MaxValue, 1)]
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public void NumberOfLeadingZeros_ReturnsCorrectValue(long value, int expected)
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{
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Assert.Equal(expected, Bitwise.NumberOfLeadingZeros(value));
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}
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}
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}

‎HdrHistogram/HdrHistogram.csproj‎

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<Project Sdk="Microsoft.NET.Sdk">
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<Project Sdk="Microsoft.NET.Sdk">
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<PropertyGroup>
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<TargetFrameworks>net10.0;net9.0;net8.0;netstandard2.0</TargetFrameworks>
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<TargetFrameworks>net10.0;net9.0;net8.0</TargetFrameworks>
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<Description>HdrHistogram supports low latency recording and analyzing of sampled data value counts across a configurable integer value range with configurable value precision within the range.</Description>
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<Authors>Gil Tene, Lee Campbell</Authors>
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<PackageReleaseNotes>Net 8.0 release</PackageReleaseNotes>
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<None Include="../README.md" Pack="true" PackagePath="" />
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</ItemGroup>
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<PropertyGroup Condition="'$(Configuration)|$(TargetFramework)|$(Platform)'=='Release|net8.0|AnyCPU'">
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<DocumentationFile>bin\Release\net8.0\HdrHistogram.xml</DocumentationFile>
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<PropertyGroup Condition="'$(Configuration)' == 'Release'">
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<DocumentationFile>bin\Release\$(TargetFramework)\HdrHistogram.xml</DocumentationFile>
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</PropertyGroup>
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<PropertyGroup Condition="'$(Configuration)|$(TargetFramework)|$(Platform)'=='Release|net9.0|AnyCPU'">
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<DocumentationFile>bin\Release\net9.0\HdrHistogram.xml</DocumentationFile>
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</PropertyGroup>
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<PropertyGroup Condition="'$(Configuration)|$(TargetFramework)|$(Platform)'=='Release|net10.0|AnyCPU'">
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<DocumentationFile>bin\Release\net10.0\HdrHistogram.xml</DocumentationFile>
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</PropertyGroup>
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<PropertyGroup Condition="'$(Configuration)|$(TargetFramework)|$(Platform)'=='Release|netstandard2.0|AnyCPU'">
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<DocumentationFile>bin\Release\netstandard2.0\HdrHistogram.xml</DocumentationFile>
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<DefineConstants>RELEASE;NETSTANDARD2_0</DefineConstants>
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</PropertyGroup>
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</Project>
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</Project>

‎HdrHistogram/HistogramLogReader.cs‎

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private static bool IsComment(string line)
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{
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#if NETSTANDARD2_0
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return line.StartsWith("#", StringComparison.Ordinal);
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#else
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return line.StartsWith('#');
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#endif
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}
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private static bool IsStartTime(string line)

‎HdrHistogram/Utilities/Bitwise.cs‎

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@@ -22,90 +22,7 @@ public static class Bitwise
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/// <returns>The number of leading zeros.</returns>
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public static int NumberOfLeadingZeros(long value)
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{
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#if NET5_0_OR_GREATER
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return IntrinsicNumberOfLeadingZeros(value);
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#else
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return Imperative.NumberOfLeadingZeros(value);
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#endif
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}
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#if NET5_0_OR_GREATER
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/// <summary>
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/// Returns the Leading Zero Count (lzc) of the <paramref name="value"/> for its binary representation.
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/// </summary>
36-
/// <param name="value">The value to find the number of leading zeros</param>
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/// <returns>The number of leading zeros.</returns>
38-
private static int IntrinsicNumberOfLeadingZeros(long value)
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{
40-
ulong testValue = (ulong)value;
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return System.Numerics.BitOperations.LeadingZeroCount(testValue);
42-
43-
}
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#endif
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//Code has been tested and taken from :
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//http://stackoverflow.com/questions/9543410/i-dont-think-numberofleadingzeroslong-i-in-long-java-is-based-floorlog2x/9543537#9543537
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//http://stackoverflow.com/questions/21888140/de-bruijn-algorithm-binary-digit-count-64bits-c-sharp/21888542#21888542
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//http://stackoverflow.com/questions/15967240/fastest-implementation-of-log2int-and-log2float
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//http://graphics.stanford.edu/~seander/bithacks.html#IntegerLogObvious
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/// <summary>
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/// Imperative implementation of the LeadingZeroCount, when access to the <c>System.Numerics.BitOperations.LeadingZeroCount(ulong)</c> is not available.
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/// </summary>
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public static class Imperative
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{
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private static readonly int[] Lookup;
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static Imperative()
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{
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Lookup = new int[256];
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for (int i = 1; i < 256; ++i)
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{
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Lookup[i] = (int)(Math.Log(i) / Math.Log(2));
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}
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}
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/// <summary>
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/// Returns the Leading Zero Count (lzc) of the <paramref name="value"/> for its binary representation.
70-
/// </summary>
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/// <param name="value">The value to find the number of leading zeros</param>
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/// <returns>The number of leading zeros.</returns>
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public static int NumberOfLeadingZeros(long value)
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{
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//Optimisation for 32 bit values. So values under 00:16:41.0 when measuring with Stopwatch.GetTimestamp()*, we will hit a fast path.
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// * as at writing on Win10 .NET 4.6
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if (value < int.MaxValue)
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return 63 - Log2((int)value);
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return NumberOfLeadingZerosLong(value);
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}
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private static int NumberOfLeadingZerosLong(long value)
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{
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// Code from http://stackoverflow.com/questions/9543410/i-dont-think-numberofleadingzeroslong-i-in-long-java-is-based-floorlog2x/9543537#9543537
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//--Already checked that values here are over int.MaxValue, i.e. !=0
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// HD, Figure 5-6
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//if (value == 0)
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// return 64;
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var n = 1;
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// >>> in Java is a "unsigned bit shift", to do the same in C# we use >> (but it HAS to be an unsigned int)
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var x = (uint)(value >> 32);
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if (x == 0) { n += 32; x = (uint)value; }
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if (x >> 16 == 0) { n += 16; x <<= 16; }
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if (x >> 24 == 0) { n += 8; x <<= 8; }
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if (x >> 28 == 0) { n += 4; x <<= 4; }
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if (x >> 30 == 0) { n += 2; x <<= 2; }
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n -= (int)(x >> 31);
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return n;
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}
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private static int Log2(int i)
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{
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if (i >= 0x1000000) { return Lookup[i >> 24] + 24; }
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if (i >= 0x10000) { return Lookup[i >> 16] + 16; }
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if (i >= 0x100) { return Lookup[i >> 8] + 8; }
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return Lookup[i];
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}
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return System.Numerics.BitOperations.LeadingZeroCount((ulong)value);
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}
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}
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}

plan/ready/brief.md renamed to plan/done/brief.md

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plan/ready/task.md renamed to plan/done/task.md

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## Implementation Changes
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- [ ] **`HdrHistogram/HdrHistogram.csproj` line 4** — Remove `netstandard2.0` from `<TargetFrameworks>`, leaving `net10.0;net9.0;net8.0`.
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- [x] **`HdrHistogram/HdrHistogram.csproj` line 4** — Remove `netstandard2.0` from `<TargetFrameworks>`, leaving `net10.0;net9.0;net8.0`.
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- **Why:** Drops the legacy target entirely.
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- **Verify:** `<TargetFrameworks>` value contains no `netstandard2.0` token.
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- [ ] **`HdrHistogram/HdrHistogram.csproj` lines 24–34** — Collapse the three per-framework Release `PropertyGroup` blocks (one each for `net8.0`, `net9.0`, `net10.0`) into a single `PropertyGroup Condition="'$(Configuration)' == 'Release'"` block with a single `<DocumentationFile>` element that resolves via `$(TargetFramework)`.
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- [x] **`HdrHistogram/HdrHistogram.csproj` lines 24–34** — Collapse the three per-framework Release `PropertyGroup` blocks (one each for `net8.0`, `net9.0`, `net10.0`) into a single `PropertyGroup Condition="'$(Configuration)' == 'Release'"` block with a single `<DocumentationFile>` element that resolves via `$(TargetFramework)`.
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- **Why:** Eliminates duplicated XML and the framework-specific condition strings.
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- **Verify:** Only one Release `PropertyGroup` exists; it contains no `$(TargetFramework)` literals in the condition string.
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- [ ] **`HdrHistogram/HdrHistogram.csproj` lines 36–39** — Delete the `netstandard2.0` `PropertyGroup` block (the one setting `DefineConstants` to `RELEASE;NETSTANDARD2_0`).
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- [x] **`HdrHistogram/HdrHistogram.csproj` lines 36–39** — Delete the `netstandard2.0` `PropertyGroup` block (the one setting `DefineConstants` to `RELEASE;NETSTANDARD2_0`).
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- **Why:** The constant `NETSTANDARD2_0` is no longer needed once the target is removed.
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- **Verify:** No `PropertyGroup` referencing `netstandard2.0` or `NETSTANDARD2_0` remains in the file.
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- [ ] **`HdrHistogram/Utilities/Bitwise.cs` lines 23–44** — Simplify `NumberOfLeadingZeros(long)` to call `System.Numerics.BitOperations.LeadingZeroCount((ulong)value)` directly; remove the `#if NET5_0_OR_GREATER` / `#else` / `#endif` guards and delete the private `IntrinsicNumberOfLeadingZeros` helper.
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- [x] **`HdrHistogram/Utilities/Bitwise.cs` lines 23–44** — Simplify `NumberOfLeadingZeros(long)` to call `System.Numerics.BitOperations.LeadingZeroCount((ulong)value)` directly; remove the `#if NET5_0_OR_GREATER` / `#else` / `#endif` guards and delete the private `IntrinsicNumberOfLeadingZeros` helper.
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- **Why:** All supported targets (net8.0+) provide `BitOperations.LeadingZeroCount`; the conditional dispatch is dead code.
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- **Verify:** `NumberOfLeadingZeros` body is a single `return System.Numerics.BitOperations.LeadingZeroCount((ulong)value);` statement; no `#if` directives remain in the method or immediately around it.
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21-
- [ ] **`HdrHistogram/Utilities/Bitwise.cs` lines 55–109** — Delete the entire `Bitwise.Imperative` nested public static class (including the `Lookup` table, `NumberOfLeadingZeros`, `NumberOfLeadingZerosLong`, and `Log2` methods).
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- [x] **`HdrHistogram/Utilities/Bitwise.cs` lines 55–109** — Delete the entire `Bitwise.Imperative` nested public static class (including the `Lookup` table, `NumberOfLeadingZeros`, `NumberOfLeadingZerosLong`, and `Log2` methods).
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- **Why:** The imperative fallback path is unreachable on net8.0+; removing it eliminates dead code and the public surface that the benchmark references.
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- **Verify:** No `class Imperative` or `Bitwise.Imperative` identifier exists anywhere in the solution.
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- [ ] **`HdrHistogram/HistogramLogReader.cs` lines 241–248** — Remove the `#if NETSTANDARD2_0` / `#else` / `#endif` block inside `IsComment(string line)`, keeping only `return line.StartsWith('#');`.
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- [x] **`HdrHistogram/HistogramLogReader.cs` lines 241–248** — Remove the `#if NETSTANDARD2_0` / `#else` / `#endif` block inside `IsComment(string line)`, keeping only `return line.StartsWith('#');`.
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- **Why:** The `char` overload of `StartsWith` is available on all net8.0+ targets; the string-overload fallback is dead code.
2727
- **Verify:** `IsComment` contains no `#if` directives; the method body is `return line.StartsWith('#');`.
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29-
- [ ] **`HdrHistogram.Benchmarking/LeadingZeroCount/LeadingZeroCountBenchmarkBase.cs`** — Remove the `"Imperative"` entry from the validation dictionary (line 56) and delete the `ImperativeImplementation()` benchmark method (lines 124–133).
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- [x] **`HdrHistogram.Benchmarking/LeadingZeroCount/LeadingZeroCountBenchmarkBase.cs`** — Remove the `"Imperative"` entry from the validation dictionary (line 56) and delete the `ImperativeImplementation()` benchmark method (lines 124–133).
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- **Why:** Both reference `Bitwise.Imperative` which will no longer exist; leaving them causes a compile error.
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- **Verify:** `dotnet build HdrHistogram.Benchmarking/ -c Release` exits with code 0; no reference to `Bitwise.Imperative` remains in the file.
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## Unit Tests
3434

35-
- [ ] **`HdrHistogram.UnitTests/`** — Add a focused unit test class `BitwiseTests` (e.g. `HdrHistogram.UnitTests/Utilities/BitwiseTests.cs`) that asserts `Bitwise.NumberOfLeadingZeros` returns correct results for representative inputs: `0`, `1`, `2`, powers of two up to 2⁶², and `long.MaxValue`.
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- [x] **`HdrHistogram.UnitTests/`** — Add a focused unit test class `BitwiseTests` (e.g. `HdrHistogram.UnitTests/Utilities/BitwiseTests.cs`) that asserts `Bitwise.NumberOfLeadingZeros` returns correct results for representative inputs: `0`, `1`, `2`, powers of two up to 2⁶², and `long.MaxValue`.
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- **Why:** No existing test directly covers `Bitwise`; this provides a regression anchor if the method is ever touched again.
3737
- **Verify:** Test class exists; `dotnet test -c Release` reports the new tests as passing on all three target frameworks.
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39-
- [ ] **Run the full unit-test suite** — Execute `dotnet test -c Release` across all three target frameworks (net8.0, net9.0, net10.0).
39+
- [x] **Run the full unit-test suite** — Execute `dotnet test -c Release` across all three target frameworks (net8.0, net9.0, net10.0).
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- **Why:** Confirms that removing the netstandard2.0 conditional paths has not broken any indirect consumer of `Bitwise` or `HistogramLogReader`.
4141
- **Verify:** Zero test failures; zero skipped tests that were previously passing.
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## Documentation
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45-
- [ ] **`spec/tech-standards/build-system.md` line 25** — Remove `netstandard2.0` from the `<TargetFrameworks>` code block example.
45+
- [x] **`spec/tech-standards/build-system.md` line 25** — Remove `netstandard2.0` from the `<TargetFrameworks>` code block example.
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- **Why:** The spec must reflect the actual supported targets.
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- **Verify:** The code block contains only `net10.0;net9.0;net8.0`.
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- [ ] **`spec/tech-standards/build-system.md` line 33** — Delete the `| \`netstandard2.0\` | Broad compatibility (.NET Framework 4.6.1+, .NET Core 2.0+) |` row from the target table.
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- [x] **`spec/tech-standards/build-system.md` line 33** — Delete the `| \`netstandard2.0\` | Broad compatibility (.NET Framework 4.6.1+, .NET Core 2.0+) |` row from the target table.
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- **Why:** The target no longer exists; the row is misleading.
5151
- **Verify:** No mention of `netstandard2.0` remains anywhere in `build-system.md`.
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‎spec/tech-standards/build-system.md‎

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### Main Library (HdrHistogram.csproj)
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```xml
25-
<TargetFrameworks>net10.0;net9.0;net8.0;netstandard2.0</TargetFrameworks>
25+
<TargetFrameworks>net10.0;net9.0;net8.0</TargetFrameworks>
2626
```
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| Target | Description |
2929
|--------|-------------|
3030
| `net10.0` | Modern .NET (current LTS target) |
3131
| `net9.0` | Modern .NET (STS target) |
3232
| `net8.0` | Modern .NET (LTS target) |
33-
| `netstandard2.0` | Broad compatibility (.NET Framework 4.6.1+, .NET Core 2.0+) |
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### Test Project
3635

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