Imported Upstream version 5.0.0.42

Former-commit-id: fd56571888259555122d8a0f58c68838229cea2b

external/linker/cecil/symbols/pdb/Microsoft.Cci.Pdb/BitSet.cs

@@ -0,0 +1,74 @@
+//-----------------------------------------------------------------------------
+//
+// Copyright (c) Microsoft. All rights reserved.
+// This code is licensed under the Microsoft Public License.
+// THIS CODE IS PROVIDED *AS IS* WITHOUT WARRANTY OF
+// ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING ANY
+// IMPLIED WARRANTIES OF FITNESS FOR A PARTICULAR
+// PURPOSE, MERCHANTABILITY, OR NON-INFRINGEMENT.
+//
+//-----------------------------------------------------------------------------
+using System;
+
+namespace Microsoft.Cci.Pdb {
+  internal struct BitSet {
+    internal BitSet(BitAccess bits) {
+      bits.ReadInt32(out size);    // 0..3 : Number of words
+      words = new uint[size];
+      bits.ReadUInt32(words);
+    }
+
+    //internal BitSet(int size) {
+    //  this.size = size;
+    //  words = new uint[size];
+    //}
+
+    internal bool IsSet(int index) {
+      int word = index / 32;
+      if (word >= this.size) return false;
+      return ((words[word] & GetBit(index)) != 0);
+    }
+
+    //internal void Set(int index) {
+    //  int word = index / 32;
+    //  if (word >= this.size) return;
+    //  words[word] |= GetBit(index);
+    //}
+
+    //internal void Clear(int index) {
+    //  int word = index / 32;
+    //  if (word >= this.size) return;
+    //  words[word] &= ~GetBit(index);
+    //}
+
+    private static uint GetBit(int index) {
+      return ((uint)1 << (index % 32));
+    }
+
+    //private static uint ReverseBits(uint value) {
+    //  uint o = 0;
+    //  for (int i = 0; i < 32; i++) {
+    //    o = (o << 1) | (value & 1);
+    //    value >>= 1;
+    //  }
+    //  return o;
+    //}
+
+    internal bool IsEmpty {
+      get { return size == 0; }
+    }
+
+    //internal bool GetWord(int index, out uint word) {
+    //  if (index < size) {
+    //    word = ReverseBits(words[index]);
+    //    return true;
+    //  }
+    //  word = 0;
+    //  return false;
+    //}
+
+    private int size;
+    private uint[] words;
+  }
+
+}