forked from BilalY/Rasagar
29 lines
1015 B
C#
29 lines
1015 B
C#
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using System;
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namespace UnityEditor.TestTools.TestRunner.GUI.Controls
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{
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/// <summary>
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/// Provides methods for dealing with common bit operations.
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/// </summary>
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internal static class BitUtility
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{
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/// <summary>
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/// Evaluates the cardinality of an integer, treating the value as a bit set.
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/// Optimization based on http://graphics.stanford.edu/~seander/bithacks.html#CountBitsSetParallel.
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/// </summary>
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/// <param name="integer">The input integer value.</param>
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/// <returns>The number of bits set in the provided input integer value.</returns>
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internal static int GetCardinality(int integer)
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{
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unchecked
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{
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integer = integer - ((integer >> 1) & 0x55555555);
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integer = (integer & 0x33333333) + ((integer >> 2) & 0x33333333);
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integer = (((integer + (integer >> 4)) & 0xF0F0F0F) * 0x1010101) >> 24;
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}
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return integer;
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}
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}
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}
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