[Vulkan] Add support for MoltenVK on macOS

This gets Vulkan support working on macOS if the Vulkan SDK and MoltenVK
are available. All current Vulkan tests except particle_life pass with
Vulkan on macOS with DXC, and sign.32.test fails with Clang.

Author: llvm-beanz

CMakeLists.txt

@@ -41,7 +41,11 @@ macro(add_offloadtest_library name)
   set_target_properties(OffloadTest${name} PROPERTIES FOLDER "Offload Test/Libraries")
 endmacro()
 
-find_package(Vulkan)
+if (APPLE)
+  set(OPTIONAL_MOLTEN COMPONENTS MoltenVK)
+endif()
+
+find_package(Vulkan ${OPTIONAL_MOLTEN})
 message(STATUS "Vulkan Include Dirs: ${Vulkan_INCLUDE_DIRS}")
 if (Vulkan_INCLUDE_DIRS)
   set(OFFLOADTEST_ENABLE_VULKAN On)

docs/MoltenVK.md

@@ -0,0 +1,16 @@
+# Enabling Vulkan on macOS with MoltenVK
+
+To enable Vulkan testing on macOS you first need to download and install the
+Vulkan SDK from [here](https://vulkan.lunarg.com).
+
+By default the SDK installs into your home directory under
+`~/VulkanSDK/${SDK_Version}/macOS`. For CMake to find the SDK you either need to
+set the `VULKAN_SDK` environment variable to the macOS subdirectory of the
+VulkanSDK installation you wish to use. You also need to run `sudo
+~/VulkanSDK/${SDK_Version}/install_vulkan.py --force-install`, to install the
+development binaries into `/usr/local/...` so that launched applications can
+find them.
+
+Once the SDK is installed and exposed to CMake, a clean configuration will
+detect Vulkan and the MoltenVK portability layer and enable the Vulkan test
+configurations.

lib/API/CMakeLists.txt

@@ -24,7 +24,8 @@ if (APPLE)
                             "-framework MetalKit"
                             "-framework AppKit"
                             "-framework Foundation"
-                            "-framework QuartzCore")
+                            "-framework QuartzCore"
+                            ${api_frameworks})
   list(APPEND api_headers PRIVATE ${METAL_INCLUDE_DIRS})
 endif()
 

lib/API/VK/Device.cpp

@@ -830,10 +830,19 @@ class VKContext {
     CreateInfo.sType = VK_STRUCTURE_TYPE_INSTANCE_CREATE_INFO;
     CreateInfo.pApplicationInfo = &AppInfo;
 
+    llvm::SmallVector<const char *> Extensions;
+#if __APPLE__
+    Extensions.push_back(VK_KHR_PORTABILITY_ENUMERATION_EXTENSION_NAME);
+    CreateInfo.flags |= VK_INSTANCE_CREATE_ENUMERATE_PORTABILITY_BIT_KHR;
+#endif
+
+    CreateInfo.ppEnabledExtensionNames = Extensions.data();
+    CreateInfo.enabledExtensionCount = Extensions.size();
+
     VkResult Res = vkCreateInstance(&CreateInfo, NULL, &Instance);
     if (Res == VK_ERROR_INCOMPATIBLE_DRIVER)
       return llvm::createStringError(std::errc::no_such_device,
-                                     "Cannot find a compatible Vulkan device");
+                                     "Cannot find a base Vulkan device");
     if (Res)
       return llvm::createStringError(std::errc::no_such_device,
                                      "Unknown Vulkan initialization error: %d",
@@ -862,6 +871,8 @@ class VKContext {
     CreateInfo.enabledLayerCount = 1;
 #endif
 
+    // This second creation shouldn't ever fail, but it tries to create the
+    // highest supported device version.
     Res = vkCreateInstance(&CreateInfo, NULL, &Instance);
     if (Res == VK_ERROR_INCOMPATIBLE_DRIVER)
       return llvm::createStringError(std::errc::no_such_device,

test/Feature/HLSLLib/sign.32.test

@@ -74,15 +74,15 @@ Buffers:
   - Name: Out2
     Format: Int32
     Stride: 16
-    ZeroInitSize: 48 
+    ZeroInitSize: 48
   - Name: ExpectedOut2 # The result we expect
     Format: Int32
     Stride: 16
     Data: [1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 0] # Last two are filler
   - Name: Out3
     Format: Int32
     Stride: 16
-    ZeroInitSize: 48 
+    ZeroInitSize: 48
   - Name: ExpectedOut3 # The result we expect
     Format: Int32
     Stride: 16
@@ -176,6 +176,9 @@ DescriptorSets:
 # https://github.com/microsoft/DirectXShaderCompiler/issues/7512
 # XFAIL: DXC-Vulkan
 
+# No idea what is going on here, but Out1 and Out3 are coming through as 0's.
+# XFAIL: Clang && Vulkan-Darwin
+
 # RUN: split-file %s %t
 # RUN: %dxc_target -T cs_6_5 -Fo %t.o %t/source.hlsl
 # RUN: %offloader %t/pipeline.yaml %t.o

test/UseCase/particle-life.test

@@ -357,6 +357,9 @@ DescriptorSets:
 # https://github.com/llvm-beanz/offload-test-suite/issues/55
 # UNSUPPORTED: Metal
 
+# No idea what is going on here, but the results are _way_ off.
+# XFAIL: Vulkan-Darwin
+
 # RUN: split-file %s %t
 # RUN: %if !Vulkan %{ %dxc_target -T cs_6_0 -Fo %t.o %t/particle-life.hlsl %}
 # RUN: %if Vulkan %{ %dxc_target -T cs_6_0 -fspv-target-env=vulkan1.3 -fvk-use-scalar-layout -Fo %t.o %t/particle-life.hlsl %}

test/lit.cfg.py

@@ -51,6 +51,7 @@
 def setDeviceFeatures(config, device, compiler):
     API = device["API"]
     config.available_features.add(API)
+    config.available_features.add("%s-%s" % (API, config.offloadtest_os))
     if "Microsoft Basic Render Driver" in device["Description"]:
         config.available_features.add("%s-WARP" % API)
     if "Intel" in device["Description"]:

test/lit.site.cfg.py.in

@@ -16,6 +16,7 @@ config.offloadtest_suite = "@suite@"
 config.offloadtest_enable_d3d12 = @TEST_d3d12@
 config.offloadtest_enable_vulkan = @TEST_vk@
 config.offloadtest_enable_metal = @TEST_mtl@
+config.offloadtest_os = "@CMAKE_SYSTEM_NAME@"
 
 import lit.llvm
 lit.llvm.initialize(lit_config, config)

tools/api-query/CMakeLists.txt

@@ -2,3 +2,8 @@ add_offloadtest_tool(api-query
               api-query.cpp)
 
 target_link_libraries(api-query PRIVATE LLVMSupport OffloadTestAPI)
+
+if (APPLE AND OFFLOADTEST_ENABLE_VULKAN)
+  set_property(TARGET api-query APPEND_STRING PROPERTY
+               LINK_FLAGS " -Wl,-rpath,/usr/local/lib ")
+endif()

tools/offloader/CMakeLists.txt

@@ -6,3 +6,8 @@ target_link_libraries(offloader PRIVATE
                       OffloadTestAPI
                       OffloadTestImage
                       OffloadTestSupport)
+
+if (APPLE AND OFFLOADTEST_ENABLE_VULKAN)
+  set_property(TARGET offloader APPEND_STRING PROPERTY
+               LINK_FLAGS " -Wl,-rpath,/usr/local/lib ")
+endif()