From c6156f4dd78de5a54ecf025870d68d75eec56b5b Mon Sep 17 00:00:00 2001
From: vsadov <8218165+VSadov@users.noreply.github.com>
Date: Wed, 16 Feb 2022 22:36:29 -0800
Subject: [PATCH 1/3] Use CopyContext to restore saved context on X86

---
 src/coreclr/vm/threadsuspend.cpp | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/coreclr/vm/threadsuspend.cpp b/src/coreclr/vm/threadsuspend.cpp
index b65cd74270b23e..0efea4b94a4295 100644
--- a/src/coreclr/vm/threadsuspend.cpp
+++ b/src/coreclr/vm/threadsuspend.cpp
@@ -2577,7 +2577,13 @@ int RedirectedHandledJITCaseExceptionFilter(
     pFrame->Pop();
 
     // Copy the saved context record into the EH context;
-    ReplaceExceptionContextRecord(pExcepPtrs->ContextRecord, pCtx);
+    // NB: cannot use ReplaceExceptionContextRecord here.
+    //     these contexts may contain extended registers and may have different format
+    //     for reasons such as alignment or context compaction
+    //
+    // REVIEW: CopyContext may fail. in theory. How should we handle that? FailFast?
+    CONTEXT* pTarget = pExcepPtrs->ContextRecord;
+    CopyContext(pTarget, pTarget->ContextFlags, pCtx);
 
     DWORD espValue = pCtx->Esp;
 

From 0e124a36ec846782ad42164d1f8c0938a275d25f Mon Sep 17 00:00:00 2001
From: vsadov <8218165+VSadov@users.noreply.github.com>
Date: Thu, 17 Feb 2022 18:21:31 -0800
Subject: [PATCH 2/3] PR feedback

---
 src/coreclr/vm/threadsuspend.cpp | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/src/coreclr/vm/threadsuspend.cpp b/src/coreclr/vm/threadsuspend.cpp
index 0efea4b94a4295..bc9fab0a0855dd 100644
--- a/src/coreclr/vm/threadsuspend.cpp
+++ b/src/coreclr/vm/threadsuspend.cpp
@@ -2509,6 +2509,18 @@ void RedirectedThreadFrame::ExceptionUnwind()
 #ifndef TARGET_UNIX
 
 #ifdef TARGET_X86
+
+// a helper to make sure these calls are not inlined into a filter function.
+// in particular we do not want a possibility of inlined destructor calls.
+NOINLINE void CopyContextHelper(CONTEXT* pTarget, CONTEXT* pCtx)
+{
+    if (!CopyContext(pTarget, pTarget->ContextFlags, pCtx))
+    {
+        STRESS_LOG1(LF_SYNC, LL_ERROR, "ERROR: Could not set context record, lastError = 0x%x\n", GetLastError());
+        ThrowLastError();
+    }
+}
+
 //****************************************************************************************
 // This will check who caused the exception.  If it was caused by the the redirect function,
 // the reason is to resume the thread back at the point it was redirected in the first
@@ -2580,10 +2592,8 @@ int RedirectedHandledJITCaseExceptionFilter(
     // NB: cannot use ReplaceExceptionContextRecord here.
     //     these contexts may contain extended registers and may have different format
     //     for reasons such as alignment or context compaction
-    //
-    // REVIEW: CopyContext may fail. in theory. How should we handle that? FailFast?
     CONTEXT* pTarget = pExcepPtrs->ContextRecord;
-    CopyContext(pTarget, pTarget->ContextFlags, pCtx);
+    CopyContextHelper(pTarget, pCtx);
 
     DWORD espValue = pCtx->Esp;
 

From bae2f4526bd5fe253ca68d876ddbd76f6f760083 Mon Sep 17 00:00:00 2001
From: vsadov <8218165+VSadov@users.noreply.github.com>
Date: Thu, 17 Feb 2022 21:06:55 -0800
Subject: [PATCH 3/3] more PR feedback

---
 src/coreclr/vm/threadsuspend.cpp | 17 +++++------------
 1 file changed, 5 insertions(+), 12 deletions(-)

diff --git a/src/coreclr/vm/threadsuspend.cpp b/src/coreclr/vm/threadsuspend.cpp
index bc9fab0a0855dd..3c6f46b4932bbe 100644
--- a/src/coreclr/vm/threadsuspend.cpp
+++ b/src/coreclr/vm/threadsuspend.cpp
@@ -2510,17 +2510,6 @@ void RedirectedThreadFrame::ExceptionUnwind()
 
 #ifdef TARGET_X86
 
-// a helper to make sure these calls are not inlined into a filter function.
-// in particular we do not want a possibility of inlined destructor calls.
-NOINLINE void CopyContextHelper(CONTEXT* pTarget, CONTEXT* pCtx)
-{
-    if (!CopyContext(pTarget, pTarget->ContextFlags, pCtx))
-    {
-        STRESS_LOG1(LF_SYNC, LL_ERROR, "ERROR: Could not set context record, lastError = 0x%x\n", GetLastError());
-        ThrowLastError();
-    }
-}
-
 //****************************************************************************************
 // This will check who caused the exception.  If it was caused by the the redirect function,
 // the reason is to resume the thread back at the point it was redirected in the first
@@ -2593,7 +2582,11 @@ int RedirectedHandledJITCaseExceptionFilter(
     //     these contexts may contain extended registers and may have different format
     //     for reasons such as alignment or context compaction
     CONTEXT* pTarget = pExcepPtrs->ContextRecord;
-    CopyContextHelper(pTarget, pCtx);
+    if (!CopyContext(pTarget, pTarget->ContextFlags, pCtx))
+    {
+        STRESS_LOG1(LF_SYNC, LL_ERROR, "ERROR: Could not set context record, lastError = 0x%x\n", GetLastError());
+        EEPOLICY_HANDLE_FATAL_ERROR(COR_E_EXECUTIONENGINE);
+    }
 
     DWORD espValue = pCtx->Esp;