Function LockJITContext

Source/Windows/WOW64/Module.cpp:363–379

}

void LockJITContext() {
  uint32_t Expected = GetTLS().ControlWord().load(), New;

  // Spin until PAUSED is unset, setting IN_JIT when that occurs
  do {
    Expected = Expected & ~ControlBits::PAUSED;
    New = (Expected | ControlBits::IN_JIT) & ~ControlBits::WOW_CPU_AREA_DIRTY;
  } while (!GetTLS().ControlWord().compare_exchange_weak(Expected, New, std::memory_order::relaxed));
  std::atomic_signal_fence(std::memory_order::seq_cst);

  // If the CPU area is dirty, flush it to the JIT context before reentry
  if (Expected & ControlBits::WOW_CPU_AREA_DIRTY) {
    WOW64_CONTEXT* WowContext;
    RtlWow64GetCurrentCpuArea(nullptr, reinterpret_cast<void**>(&WowContext), nullptr);
    Context::LoadStateFromWowContext(GetTLS().ThreadState(), GetWowTEB(NtCurrentTeb()), WowContext);
  }
}

void UnlockJITContext() {
  std::atomic_signal_fence(std::memory_order::seq_cst);