Simplify 64bit mask

TechPizzaDev · Jan 23, 2025 · 2aeeb88 · 2aeeb88
1 parent c8ae57e
commit 2aeeb88
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Showing 2 changed files with 9 additions and 10 deletions.
diff --git a/NVorbis/Utils.cs b/NVorbis/Utils.cs
@@ -9,13 +9,6 @@ internal static class Utils
         private const float LowerClip = -0.99999994f;
         private const float UpperClip = 0.99999994f;
 
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        internal static ulong Mask64(int bitCount)
-        {
-            ulong mask = bitCount == 0 ? 0 : ulong.MaxValue;
-            return mask >> (64 - bitCount);
-        }
-
         internal static int ilog(int x)
         {
             int cnt = 0;

diff --git a/NVorbis/VorbisPacket.cs b/NVorbis/VorbisPacket.cs
@@ -182,7 +182,10 @@ private ulong RefillBits(ref int count)
             {
                 count = _bitCount;
             }
-            return _bitBucket & Utils.Mask64(count);
+
+            ulong value = _bitBucket;
+            ulong mask = ulong.MaxValue >> (64 - count);
+            return value & mask;
         }
 
         /// <summary>
@@ -194,14 +197,17 @@ private ulong RefillBits(ref int count)
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public ulong TryPeekBits(int count, out int bitsRead)
         {
-            Debug.Assert((uint)count <= 64);
+            Debug.Assert((uint)(count - 1) < 64);
 
             bitsRead = count;
             if (_bitCount < count)
             {
                 return RefillBits(ref bitsRead);
             }
-            return _bitBucket & Utils.Mask64(count);
+
+            ulong value = _bitBucket;
+            ulong mask = ulong.MaxValue >> (64 - count);
+            return value & mask;
         }
 
         /// <summary>