From f48071dcbef0cacb09772266f7043bb0dfd551e6 Mon Sep 17 00:00:00 2001
From: Billy Laws <blaws05@gmail.com>
Date: Wed, 31 Jul 2024 17:08:06 +0000
Subject: [PATCH] ARM64EC: Switch to the emulator stack in BeginSimulation

Windows calls this function on the guest stack for some reason.
---
 Source/Windows/ARM64EC/Module.S | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Source/Windows/ARM64EC/Module.S b/Source/Windows/ARM64EC/Module.S
index 1ed2bd599..9d8e169ee 100644
--- a/Source/Windows/ARM64EC/Module.S
+++ b/Source/Windows/ARM64EC/Module.S
@@ -41,6 +41,9 @@ enter_jit:
   // Expects a CONTEXT pointer in x0
 .global BeginSimulation
 BeginSimulation:
+  ldr x17, [x18, #0x1788] // TEB->ChpeV2CpuAreaInfo
+  ldr x16, [x17, #0x8] // ChpeV2CpuAreaInfo->EmulatorStackBase
+  mov sp, x16
   bl "#SyncThreadContext"
   ldr x17, [x18, #0x1788] // TEB->ChpeV2CpuAreaInfo
   ldr x16, [x17, #0x48] // ChpeV2CpuAreaInfo->EmulatorData[3] - DispatcherLoopTopEnterECFillSRA