Support for x64 on ARM64

.github/actions/spelling/expect.txt

@@ -130,6 +130,7 @@ hhx
 HINSTANCE
 hkey
 hlocal
+hmodule
 hre
 hresults
 htm
@@ -246,6 +247,7 @@ pkindex
 PMS
 positionals
 powertoys
+processthreads
 productcode
 pseudocode
 pvk

src/AppInstallerCommonCore/Architecture.cpp

@@ -21,6 +21,60 @@ namespace AppInstaller::Utility
             }
         }
 
+        // These types are defined in a future SDK and can be removed when we actually have them available.
+        // The exception is that None was added (and this is an enum class).
+        enum class MACHINE_ATTRIBUTES {
+            None = 0,
+            UserEnabled = 0x00000001,
+            KernelEnabled = 0x00000002,
+            Wow64Container = 0x00000004
+        };
+
+        DEFINE_ENUM_FLAG_OPERATORS(MACHINE_ATTRIBUTES);
+
+        using GetMachineTypeAttributesPtr = HRESULT(WINAPI*)(USHORT Machine, MACHINE_ATTRIBUTES* MachineTypeAttributes);
+
+        // GetMachineTypeAttributes can apparently replace IsWow64GuestMachineSupported, but no reason to do so right now.
+        struct GetMachineTypeAttributesHelper
+        {
+            GetMachineTypeAttributesHelper()
+            {
+                m_module.reset(LoadLibraryEx(L"api-ms-win-core-processthreads-l1-1-7.dll", NULL, LOAD_LIBRARY_SEARCH_SYSTEM32));
+                if (!m_module)
+                {
+                    AICLI_LOG(Core, Verbose, << "Could not load api-ms-win-core-processthreads-l1-1-7.dll");
+                    return;
+                }
+
+                m_getMachineTypeAttributes =
+                    reinterpret_cast<GetMachineTypeAttributesPtr>(GetProcAddress(m_module.get(), "GetMachineTypeAttributes"));
+                if (!m_getMachineTypeAttributes)
+                {
+                    AICLI_LOG(Core, Verbose, << "Could not get proc address of GetMachineTypeAttributes");
+                    return;
+                }
+            }
+
+            void AddArchitectureIfMachineTypeAttributesUserEnabled(std::vector<Architecture>& target, Architecture architecture, USHORT guestMachine)
+            {
+                if (m_getMachineTypeAttributes)
+                {
+                    MACHINE_ATTRIBUTES attributes = MACHINE_ATTRIBUTES::None;
+                    if (SUCCEEDED_LOG(m_getMachineTypeAttributes(guestMachine, &attributes)))
+                    {
+                        if (WI_IsFlagSet(attributes, MACHINE_ATTRIBUTES::UserEnabled))
+                        {
+                            target.push_back(architecture);
+                        }
+                    }
+                }
+            }
+
+        private:
+            wil::unique_hmodule m_module;
+            GetMachineTypeAttributesPtr m_getMachineTypeAttributes = nullptr;
+        };
+
         // Gets the applicable architectures for the current machine.
         std::vector<Architecture> CreateApplicableArchitecturesVector()
         {
@@ -29,10 +83,15 @@ namespace AppInstaller::Utility
             switch (GetSystemArchitecture())
             {
             case Architecture::Arm64:
+            {
+                GetMachineTypeAttributesHelper helper;
+
                 applicableArchs.push_back(Architecture::Arm64);
                 AddArchitectureIfGuestMachineSupported(applicableArchs, Architecture::Arm, IMAGE_FILE_MACHINE_ARMNT);
+                helper.AddArchitectureIfMachineTypeAttributesUserEnabled(applicableArchs, Architecture::X64, IMAGE_FILE_MACHINE_AMD64);
                 AddArchitectureIfGuestMachineSupported(applicableArchs, Architecture::X86, IMAGE_FILE_MACHINE_I386);
                 applicableArchs.push_back(Architecture::Neutral);
+            }
                 break;
             case Architecture::Arm:
                 applicableArchs.push_back(Architecture::Arm);