From d9f4e01930f78f1c42c29514ea18fe05dee248f6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?G=C3=BCnther=20Foidl?= <gue@korporal.at>
Date: Mon, 4 Apr 2022 19:50:47 +0200
Subject: [PATCH] BitHelper needs local Span due to regression in jit-diff
 otherwise

---
 .../Common/src/System/Collections/Generic/BitHelper.cs | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/src/libraries/Common/src/System/Collections/Generic/BitHelper.cs b/src/libraries/Common/src/System/Collections/Generic/BitHelper.cs
index ee71f1002a958..cf843526fb3c2 100644
--- a/src/libraries/Common/src/System/Collections/Generic/BitHelper.cs
+++ b/src/libraries/Common/src/System/Collections/Generic/BitHelper.cs
@@ -20,18 +20,20 @@ internal BitHelper(Span<int> span, bool clear)
         internal void MarkBit(int bitPosition)
         {
             uint bitArrayIndex = (uint)bitPosition / IntSize;
-            if (bitArrayIndex < (uint)_span.Length)
+            Span<int> span = _span;
+            if (bitArrayIndex < (uint)span.Length)
             {
-                _span[(int)bitArrayIndex] |= (1 << (int)((uint)bitPosition % IntSize));
+                span[(int)bitArrayIndex] |= (1 << (int)((uint)bitPosition % IntSize));
             }
         }
 
         internal bool IsMarked(int bitPosition)
         {
             uint bitArrayIndex = (uint)bitPosition / IntSize;
+            Span<int> span = _span;
             return
-                bitArrayIndex < (uint)_span.Length &&
-                (_span[(int)bitArrayIndex] & ((int)((uint)bitPosition % IntSize))) != 0;
+                bitArrayIndex < (uint)span.Length &&
+                (span[(int)bitArrayIndex] & ((int)((uint)bitPosition % IntSize))) != 0;
         }
 
         /// <summary>How many ints must be allocated to represent n bits. Returns (n+31)/32, but avoids overflow.</summary>