From db20f3f1bb8595633a7e16c8900fd401a453a6b5 Mon Sep 17 00:00:00 2001 From: Jiyoung Yun Date: Tue, 27 Dec 2016 16:46:08 +0900 Subject: Imported Upstream version 1.0.0.9127 --- src/mscorlib/corefx/System/Buffers/Utilities.cs | 35 +++++++++++++++++++++++++ 1 file changed, 35 insertions(+) create mode 100644 src/mscorlib/corefx/System/Buffers/Utilities.cs (limited to 'src/mscorlib/corefx/System/Buffers/Utilities.cs') diff --git a/src/mscorlib/corefx/System/Buffers/Utilities.cs b/src/mscorlib/corefx/System/Buffers/Utilities.cs new file mode 100644 index 0000000000..823299f5fc --- /dev/null +++ b/src/mscorlib/corefx/System/Buffers/Utilities.cs @@ -0,0 +1,35 @@ +// Licensed to the .NET Foundation under one or more agreements. +// The .NET Foundation licenses this file to you under the MIT license. +// See the LICENSE file in the project root for more information. + +using System.Diagnostics; +using System.Runtime.CompilerServices; + +namespace System.Buffers +{ + internal static class Utilities + { + [MethodImpl(MethodImplOptions.AggressiveInlining)] + internal static int SelectBucketIndex(int bufferSize) + { + uint bitsRemaining = ((uint)bufferSize - 1) >> 4; + + int poolIndex = 0; + if (bitsRemaining > 0xFFFF) { bitsRemaining >>= 16; poolIndex = 16; } + if (bitsRemaining > 0xFF) { bitsRemaining >>= 8; poolIndex += 8; } + if (bitsRemaining > 0xF) { bitsRemaining >>= 4; poolIndex += 4; } + if (bitsRemaining > 0x3) { bitsRemaining >>= 2; poolIndex += 2; } + if (bitsRemaining > 0x1) { bitsRemaining >>= 1; poolIndex += 1; } + + return poolIndex + (int)bitsRemaining; + } + + [MethodImpl(MethodImplOptions.AggressiveInlining)] + internal static int GetMaxSizeForBucket(int binIndex) + { + int maxSize = 16 << binIndex; + Debug.Assert(maxSize >= 0); + return maxSize; + } + } +} -- cgit v1.2.3