From: Levi Broderick <GrabYourPitchforks@users.noreply.github.com>
Date: Wed, 17 Apr 2019 03:12:12 +0000 (-0700)
Subject: Fix incorrect EHCount calculation (#24048)
X-Git-Tag: accepted/tizen/unified/20190813.215958~46^2~43
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=aa9825aad965879fae2dab9afd1a86564f856fe9;p=platform%2Fupstream%2Fcoreclr.git

Fix incorrect EHCount calculation (#24048)
---

diff --git a/src/System.Private.CoreLib/src/System/Reflection/Emit/DynamicILGenerator.cs b/src/System.Private.CoreLib/src/System/Reflection/Emit/DynamicILGenerator.cs
index fb763a5..d26d97d 100644
--- a/src/System.Private.CoreLib/src/System/Reflection/Emit/DynamicILGenerator.cs
+++ b/src/System.Private.CoreLib/src/System/Reflection/Emit/DynamicILGenerator.cs
@@ -724,7 +724,12 @@ namespace System.Reflection.Emit
 
                 if ((header & 0x40) != 0) // Fat
                 {
-                    EHCount = (BinaryPrimitives.ReadInt32LittleEndian(m_exceptionHeader.AsSpan(1)) - 4) / 24;
+                    // Positions 1..3 of m_exceptionHeader are a 24-bit little-endian integer.
+                    int size = m_exceptionHeader[3] << 16;
+                    size |= m_exceptionHeader[2] << 8;
+                    size |= m_exceptionHeader[1];
+
+                    EHCount = (size - 4) / 24;
                 }
                 else
                     EHCount = (m_exceptionHeader[1] - 2) / 12;