From 6a96d262e751cb1ca4abba4d774a75f920c1fce0 Mon Sep 17 00:00:00 2001
From: Grant Dickinson <grant@k2.com>
Date: Mon, 28 Jan 2019 18:50:57 -0800
Subject: [PATCH 1/2] Update call sites for
 https://github.com/dotnet/corert/pull/6911

---
 .../AccountManagement/Utils.cs                  |  4 ++--
 .../Internal/Utilities/BitArithmetic.cs         | 17 +++--------------
 2 files changed, 5 insertions(+), 16 deletions(-)

diff --git a/src/System.DirectoryServices.AccountManagement/src/System/DirectoryServices/AccountManagement/Utils.cs b/src/System.DirectoryServices.AccountManagement/src/System/DirectoryServices/AccountManagement/Utils.cs
index bf66ae06960d..5619e2036788 100644
--- a/src/System.DirectoryServices.AccountManagement/src/System/DirectoryServices/AccountManagement/Utils.cs
+++ b/src/System.DirectoryServices.AccountManagement/src/System/DirectoryServices/AccountManagement/Utils.cs
@@ -45,12 +45,12 @@ internal static bool AreBytesEqual(byte[] src, byte[] tgt)
 
         internal static void ClearBit(ref int value, uint bitmask)
         {
-            value = (int)(((uint)value) & ((uint)(~bitmask)));
+            BitOps.ClearBit(ref value, (int)bitmask);
         }
 
         internal static void SetBit(ref int value, uint bitmask)
         {
-            value = (int)(((uint)value) | ((uint)bitmask));
+            BitOps.InsertBit(ref value, (uint)bitmask);
         }
 
         // {0xa2, 0x3f,...} --> "a23f..."
diff --git a/src/System.Reflection.Metadata/src/System/Reflection/Internal/Utilities/BitArithmetic.cs b/src/System.Reflection.Metadata/src/System/Reflection/Internal/Utilities/BitArithmetic.cs
index bbf3d81370e8..1721856f6f6d 100644
--- a/src/System.Reflection.Metadata/src/System/Reflection/Internal/Utilities/BitArithmetic.cs
+++ b/src/System.Reflection.Metadata/src/System/Reflection/Internal/Utilities/BitArithmetic.cs
@@ -10,28 +10,17 @@ internal static class BitArithmetic
     {
         internal static int CountBits(int v)
         {
-            return CountBits(unchecked((uint)v));
+            return BitOps.PopCount(v);
         }
 
         internal static int CountBits(uint v)
         {
-            unchecked
-            {
-                v = v - ((v >> 1) & 0x55555555u);
-                v = (v & 0x33333333u) + ((v >> 2) & 0x33333333u);
-                return (int)((v + (v >> 4) & 0xF0F0F0Fu) * 0x1010101u) >> 24;
-            }
+            return BitOps.PopCount(v);
         }
 
         internal static int CountBits(ulong v)
         {
-            const ulong Mask01010101 = 0x5555555555555555UL;
-            const ulong Mask00110011 = 0x3333333333333333UL;
-            const ulong Mask00001111 = 0x0F0F0F0F0F0F0F0FUL;
-            const ulong Mask00000001 = 0x0101010101010101UL;
-            v = v - ((v >> 1) & Mask01010101);
-            v = (v & Mask00110011) + ((v >> 2) & Mask00110011);
-            return (int)(unchecked(((v + (v >> 4)) & Mask00001111) * Mask00000001) >> 56);
+            return BitOps.PopCount(v);
         }
 
         internal static uint Align(uint position, uint alignment)

From 6485bf12c1eb7a415a74b4cf147dfb95154a7ea6 Mon Sep 17 00:00:00 2001
From: Grant Dickinson <grant@k2.com>
Date: Mon, 28 Jan 2019 20:30:14 -0800
Subject: [PATCH 2/2] Another callsite

---
 src/Common/src/System/Net/WebSockets/ManagedWebSocket.cs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Common/src/System/Net/WebSockets/ManagedWebSocket.cs b/src/Common/src/System/Net/WebSockets/ManagedWebSocket.cs
index 86c5ba9e50ae..0f9898bc6c28 100644
--- a/src/Common/src/System/Net/WebSockets/ManagedWebSocket.cs
+++ b/src/Common/src/System/Net/WebSockets/ManagedWebSocket.cs
@@ -1262,7 +1262,7 @@ private static unsafe int ApplyMask(Span<byte> toMask, int mask, int maskIndex)
             Debug.Assert(maskIndex < sizeof(int));
 
             int maskShift = maskIndex * 8;
-            int shiftedMask = (int)(((uint)mask >> maskShift) | ((uint)mask << (32 - maskShift)));
+            int shiftedMask = BitOps.RotateRight(mask, maskShift);
 
             // Try to use SIMD.  We can if the number of bytes we're trying to mask is at least as much
             // as the width of a vector and if the width is an even multiple of the mask.