[debugger] Fix debugging a x86 app in mixed mode (#114075)

* Fixing get incomplete context information and assigning invalid information to the context later.

Author: thaystg

src/coreclr/debug/di/process.cpp

@@ -13317,7 +13317,11 @@ void CordbProcess::HandleDebugEventForInteropDebugging(const DEBUG_EVENT * pEven
         {
             LOG((LF_CORDB, LL_INFO100000, "W32ET::W32EL: hijack complete will restore context...\n"));
             DT_CONTEXT tempContext = { 0 };
+#if defined(DT_CONTEXT_EXTENDED_REGISTERS)            
+            tempContext.ContextFlags = DT_CONTEXT_FULL | DT_CONTEXT_EXTENDED_REGISTERS;
+#else
             tempContext.ContextFlags = DT_CONTEXT_FULL;
+#endif            
             HRESULT hr = pUnmanagedThread->GetThreadContext(&tempContext);
             _ASSERTE(SUCCEEDED(hr));
 

src/coreclr/debug/di/rsthread.cpp

@@ -3721,9 +3721,14 @@ HRESULT CordbUnmanagedThread::SetupFirstChanceHijackForSync()
     LOG((LF_CORDB, LL_INFO10000, "CUT::SFCHFS: hijackCtx started as:\n"));
     LogContext(GetHijackCtx());
 
-    // Save the thread's full context.
+    // Save the thread's full context + DT_CONTEXT_EXTENDED_REGISTERS 
+    // to avoid getting incomplete information and corrupt the thread context
     DT_CONTEXT context;
+#if defined(DT_CONTEXT_EXTENDED_REGISTERS) 
+    context.ContextFlags = DT_CONTEXT_FULL | DT_CONTEXT_EXTENDED_REGISTERS;
+#else
     context.ContextFlags = DT_CONTEXT_FULL;
+#endif    
     BOOL succ = DbiGetThreadContext(m_handle, &context);
     _ASSERTE(succ);
     // for debugging when GetThreadContext fails
@@ -3732,8 +3737,11 @@ HRESULT CordbUnmanagedThread::SetupFirstChanceHijackForSync()
         DWORD error = GetLastError();
         LOG((LF_CORDB, LL_ERROR, "CUT::SFCHFS: DbiGetThreadContext error=0x%x\n", error));
     }
-
+#if defined(DT_CONTEXT_EXTENDED_REGISTERS)
+    GetHijackCtx()->ContextFlags = DT_CONTEXT_FULL | DT_CONTEXT_EXTENDED_REGISTERS;
+#else
     GetHijackCtx()->ContextFlags = DT_CONTEXT_FULL;
+#endif    
     CORDbgCopyThreadContext(GetHijackCtx(), &context);
     LOG((LF_CORDB, LL_INFO10000, "CUT::SFCHFS: thread=0x%x Hijacking for sync. Original context is:\n", this));
     LogContext(GetHijackCtx());