From 2f16d25ab8c7bf642d926d35235f9111cf6bc891 Mon Sep 17 00:00:00 2001
From: Billy Laws <blaws05@gmail.com>
Date: Mon, 14 Jul 2025 21:20:03 +0100
Subject: [PATCH] ARM64EC: Implement call-ret stack management

---
 Source/Windows/ARM64EC/Module.cpp | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/Source/Windows/ARM64EC/Module.cpp b/Source/Windows/ARM64EC/Module.cpp
index 0d1fdd4bc..190e0eff0 100644
--- a/Source/Windows/ARM64EC/Module.cpp
+++ b/Source/Windows/ARM64EC/Module.cpp
@@ -27,6 +27,7 @@ $end_info$
 #include <FEXCore/Utils/SignalScopeGuards.h>
 
 #include "Common/ArgumentLoader.h"
+#include "Common/CallRetStack.h"
 #include "Common/Config.h"
 #include "Common/Exception.h"
 #include "Common/InvalidationTracker.h"
@@ -705,6 +706,10 @@ bool ResetToConsistentStateImpl(EXCEPTION_RECORD* Exception, CONTEXT* GuestConte
   if (Exception->ExceptionCode == EXCEPTION_ACCESS_VIOLATION) {
     const auto FaultAddress = static_cast<uint64_t>(Exception->ExceptionInformation[1]);
 
+    if (FEX::Windows::CallRetStack::HandleAccessViolation(Thread, FaultAddress, NativeContext->X17)) {
+      return true;
+    }
+
     std::scoped_lock Lock(ThreadCreationMutex);
     if (InvalidationTracker && InvalidationTracker->HandleRWXAccessViolation(FaultAddress)) {
       FEXCORE_PROFILE_INSTANT_INCREMENT(Thread, AccumulatedSMCCount, 1);
@@ -899,6 +904,8 @@ NTSTATUS ThreadInit() {
   const auto CPUArea = GetCPUArea();
 
   auto* Thread = CTX->CreateThread(0, 0);
+
+  FEX::Windows::CallRetStack::InitializeThread(Thread);
   Thread->CurrentFrame->Pointers.Common.ExitFunctionEC = reinterpret_cast<uintptr_t>(&ExitFunctionEC);
   CPUArea.StateFrame() = Thread->CurrentFrame;
 
@@ -957,6 +964,7 @@ NTSTATUS ThreadTerm(HANDLE Thread, LONG ExitCode) {
     }
   }
 
+  FEX::Windows::CallRetStack::DestroyThread(OldThreadState);
   CTX->DestroyThread(OldThreadState);
   ::VirtualFree(reinterpret_cast<void*>(CPUArea.EmulatorStackLimit()), 0, MEM_RELEASE);
   if (ThreadTID == GetCurrentThreadId()) {