Code:
/ Net / Net / 3.5.50727.3053 / DEVDIV / depot / DevDiv / releases / whidbey / netfxsp / ndp / fx / src / Xml / System / Xml / Bits.cs / 1 / Bits.cs
//------------------------------------------------------------------------------ //// Copyright (c) Microsoft Corporation. All rights reserved. // //[....] //----------------------------------------------------------------------------- namespace System.Xml { using System; using System.Diagnostics; ////// Contains static utility methods used to manipulate bits in a word. /// internal static class Bits { private static readonly uint MASK_0101010101010101 = 0x55555555; private static readonly uint MASK_0011001100110011 = 0x33333333; private static readonly uint MASK_0000111100001111 = 0x0f0f0f0f; private static readonly uint MASK_0000000011111111 = 0x00ff00ff; private static readonly uint MASK_1111111111111111 = 0x0000ffff; ////// Returns the number of 1 bits in an unsigned integer. Counts bits by divide-and-conquer method, /// first computing 16 2-bit counts, then 8 4-bit counts, then 4 8-bit counts, then 2 16-bit counts, /// and finally 1 32-bit count. /// public static int Count(uint num) { num = (num & MASK_0101010101010101) + ((num >> 1) & MASK_0101010101010101); num = (num & MASK_0011001100110011) + ((num >> 2) & MASK_0011001100110011); num = (num & MASK_0000111100001111) + ((num >> 4) & MASK_0000111100001111); num = (num & MASK_0000000011111111) + ((num >> 8) & MASK_0000000011111111); num = (num & MASK_1111111111111111) + (num >> 16); return (int) num; } ////// Returns true if the unsigned integer has exactly one bit set. /// public static bool ExactlyOne(uint num) { return num != 0 && (num & (num - 1)) == 0; } ////// Returns true if the unsigned integer has more than one bit set. /// public static bool MoreThanOne(uint num) { return (num & (num - 1)) != 0; } ////// Clear the least significant bit that is set and return the result. /// public static uint ClearLeast(uint num) { return num & (num - 1); } ////// Compute the 1-based position of the least sigificant bit that is set, and return it (return 0 if no bits are set). /// (e.g. 0x1001100 will return 3, since the 3rd bit is set). /// public static int LeastPosition(uint num) { if (num == 0) return 0; return Count(num ^ (num - 1)); } } } // File provided for Reference Use Only by Microsoft Corporation (c) 2007. //------------------------------------------------------------------------------ //// Copyright (c) Microsoft Corporation. All rights reserved. // //[....] //----------------------------------------------------------------------------- namespace System.Xml { using System; using System.Diagnostics; ////// Contains static utility methods used to manipulate bits in a word. /// internal static class Bits { private static readonly uint MASK_0101010101010101 = 0x55555555; private static readonly uint MASK_0011001100110011 = 0x33333333; private static readonly uint MASK_0000111100001111 = 0x0f0f0f0f; private static readonly uint MASK_0000000011111111 = 0x00ff00ff; private static readonly uint MASK_1111111111111111 = 0x0000ffff; ////// Returns the number of 1 bits in an unsigned integer. Counts bits by divide-and-conquer method, /// first computing 16 2-bit counts, then 8 4-bit counts, then 4 8-bit counts, then 2 16-bit counts, /// and finally 1 32-bit count. /// public static int Count(uint num) { num = (num & MASK_0101010101010101) + ((num >> 1) & MASK_0101010101010101); num = (num & MASK_0011001100110011) + ((num >> 2) & MASK_0011001100110011); num = (num & MASK_0000111100001111) + ((num >> 4) & MASK_0000111100001111); num = (num & MASK_0000000011111111) + ((num >> 8) & MASK_0000000011111111); num = (num & MASK_1111111111111111) + (num >> 16); return (int) num; } ////// Returns true if the unsigned integer has exactly one bit set. /// public static bool ExactlyOne(uint num) { return num != 0 && (num & (num - 1)) == 0; } ////// Returns true if the unsigned integer has more than one bit set. /// public static bool MoreThanOne(uint num) { return (num & (num - 1)) != 0; } ////// Clear the least significant bit that is set and return the result. /// public static uint ClearLeast(uint num) { return num & (num - 1); } ////// Compute the 1-based position of the least sigificant bit that is set, and return it (return 0 if no bits are set). /// (e.g. 0x1001100 will return 3, since the 3rd bit is set). /// public static int LeastPosition(uint num) { if (num == 0) return 0; return Count(num ^ (num - 1)); } } } // File provided for Reference Use Only by Microsoft Corporation (c) 2007.
Link Menu
This book is available now!
Buy at Amazon US or
Buy at Amazon UK
- StylusOverProperty.cs
- TableTextElementCollectionInternal.cs
- FileRecordSequenceHelper.cs
- StylusPointDescription.cs
- NetDispatcherFaultException.cs
- MD5.cs
- X509Extension.cs
- StylusOverProperty.cs
- HttpVersion.cs
- AttachedPropertyDescriptor.cs
- TextElement.cs
- TemplateBindingExtensionConverter.cs
- SslStream.cs
- MeasureItemEvent.cs
- PointAnimationClockResource.cs
- BaseParser.cs
- Connector.xaml.cs
- RectAnimationUsingKeyFrames.cs
- XmlSerializerNamespaces.cs
- XPathEmptyIterator.cs
- ConversionContext.cs
- PointCollectionConverter.cs
- RemotingConfiguration.cs
- Image.cs
- SchemaType.cs
- IconConverter.cs
- VirtualDirectoryMappingCollection.cs
- EncryptedType.cs
- DynamicArgumentDesigner.xaml.cs
- Helper.cs
- UntypedNullExpression.cs
- ModulesEntry.cs
- DetailsViewAutoFormat.cs
- ProvidersHelper.cs
- StringFunctions.cs
- RegexWriter.cs
- DependencyObjectProvider.cs
- DataSourceDesigner.cs
- Material.cs
- DesignerSerializationVisibilityAttribute.cs
- AnimationTimeline.cs
- LineInfo.cs
- MDIControlStrip.cs
- ServerIdentity.cs
- SiteMapNodeCollection.cs
- HandlerWithFactory.cs
- WorkflowServiceNamespace.cs
- RankException.cs
- ReadOnlyCollectionBase.cs
- RSAPKCS1SignatureFormatter.cs
- EntityDataSourceSelectedEventArgs.cs
- PackageController.cs
- ItemsControl.cs
- XmlDeclaration.cs
- SmtpAuthenticationManager.cs
- CancellationToken.cs
- DataGridViewCellStyle.cs
- ResourceReferenceExpression.cs
- ClientSettingsStore.cs
- UserControlParser.cs
- ObjectNavigationPropertyMapping.cs
- OperationDescriptionCollection.cs
- PkcsUtils.cs
- NegotiateStream.cs
- IdentityReference.cs
- PromptBuilder.cs
- CounterSetInstance.cs
- ProfileGroupSettingsCollection.cs
- DataBindingHandlerAttribute.cs
- XamlPointCollectionSerializer.cs
- CoTaskMemHandle.cs
- ArrangedElementCollection.cs
- SqlWebEventProvider.cs
- DefaultHttpHandler.cs
- PropertySourceInfo.cs
- Block.cs
- RowToParametersTransformer.cs
- _ShellExpression.cs
- ValidatorCompatibilityHelper.cs
- ChannelCredentials.cs
- FontFamilyConverter.cs
- PrintingPermissionAttribute.cs
- ListenerChannelContext.cs
- CellParaClient.cs
- HandleRef.cs
- CodeTypeConstructor.cs
- InheritablePropertyChangeInfo.cs
- OutputScopeManager.cs
- ExpressionSelection.cs
- CodeIndexerExpression.cs
- PanelStyle.cs
- FileSystemWatcher.cs
- ListBoxItem.cs
- SqlDataAdapter.cs
- FileClassifier.cs
- ObjectHelper.cs
- HttpResponse.cs
- DataGridViewRowCancelEventArgs.cs
- SByteStorage.cs
- DefaultHttpHandler.cs