From 43b89b4a40f7642891e48801d56bd706ab717d6b Mon Sep 17 00:00:00 2001
From: mikelle-rogers <45022607+mikelle-rogers@users.noreply.github.com>
Date: Thu, 12 Dec 2024 15:23:12 -0800
Subject: [PATCH] Correct arm64 SignExtension (#110635)

* correct arm64 SignExtension

* check for the 28th bit
---
 src/coreclr/debug/ee/arm64/walker.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/coreclr/debug/ee/arm64/walker.cpp b/src/coreclr/debug/ee/arm64/walker.cpp
index 12b9e3b121b54..ebec232a9afb9 100644
--- a/src/coreclr/debug/ee/arm64/walker.cpp
+++ b/src/coreclr/debug/ee/arm64/walker.cpp
@@ -278,9 +278,9 @@ BOOL  NativeWalker::DecodePCRelativeBranchInst(PT_CONTEXT context, const PRD_TYP
     {
         offset = (opcode & 0x03FFFFFF) << 2;
         // Sign extension
-        if ((offset & 0x4000000)) //Check for 26'st bit
+        if ((offset & 0x8000000)) //Check for (26 + 2)'st bit
         {
-            offset = offset | 0xFFFFFFFFF8000000;
+            offset = offset | 0xFFFFFFFFF0000000;
         }
 
         if ((opcode & 0x80000000) != 0) //BL