Merge pull request #76569 from kateinoigakukun/yt/fix-macos-cross-compile-wasm

[wasm] Fix cross-compilation on macOS host

Author: kateinoigakukun

CMakeLists.txt

@@ -155,6 +155,8 @@ else()
     set(SWIFT_HOST_VARIANT_SDK_default "ANDROID")
   elseif("${CMAKE_SYSTEM_NAME}" STREQUAL "Darwin")
     set(SWIFT_HOST_VARIANT_SDK_default "OSX")
+  elseif("${CMAKE_SYSTEM_NAME}" STREQUAL "WASI")
+    set(SWIFT_HOST_VARIANT_SDK_default "WASI")
   else()
     message(FATAL_ERROR "Unable to detect SDK for host system: ${CMAKE_SYSTEM_NAME}")
   endif()

utils/swift_build_support/swift_build_support/products/wasmstdlib.py

@@ -17,6 +17,8 @@
 from . import swift
 from . import wasisysroot
 from . import wasmkit
+from .. import cmake
+from .. import shell
 
 
 class WasmStdlib(cmake_product.CMakeProduct):
@@ -39,11 +41,52 @@ def should_test(self, host_target):
         return self.args.test_wasmstdlib
 
     def build(self, host_target):
-        self._build(host_target, 'wasm32-wasi')
+        self._build(host_target, 'wasm32-wasi', 'wasi-wasm32')
 
-    def _build(self, host_target, target_triple):
+    def _build(self, host_target, target_triple, short_triple):
+        llvm_build_dir = self._configure_llvm(target_triple, short_triple)
+        llvm_cmake_dir = os.path.join(llvm_build_dir, 'lib', 'cmake', 'llvm')
+        self._build_stdlib(host_target, target_triple, llvm_cmake_dir)
+
+    def _configure_llvm(self, target_triple, short_triple):
+        # Configure LLVM for WebAssembly target independently
+        # from the native LLVM build to turn off zlib and libxml2
+        build_root = os.path.dirname(self.build_dir)
+        build_dir = os.path.join(
+            build_root, 'llvm-%s' % short_triple)
+        llvm_source_dir = os.path.join(
+            os.path.dirname(self.source_dir), 'llvm-project', 'llvm')
+        cmake_options = cmake.CMakeOptions()
+        cmake_options.define('CMAKE_BUILD_TYPE:STRING', self._build_variant)
+        # compiler-rt for WebAssembly target is not installed in the host toolchain
+        # so skip compiler health checks here.
+        cmake_options.define('CMAKE_C_COMPILER_WORKS:BOOL', 'TRUE')
+        cmake_options.define('CMAKE_CXX_COMPILER_WORKS:BOOL', 'TRUE')
+        cmake_options.define('LLVM_COMPILER_CHECKED:BOOL', 'TRUE')
+        cmake_options.define('LLVM_ENABLE_ZLIB:BOOL', 'FALSE')
+        cmake_options.define('LLVM_ENABLE_LIBXML2:BOOL', 'FALSE')
+        cmake_options.define('LLVM_ENABLE_LIBEDIT:BOOL', 'FALSE')
+        cmake_options.define('LLVM_ENABLE_TERMINFO:BOOL', 'FALSE')
+
+        llvm_cmake = cmake.CMake(
+            self.args, self.toolchain, prefer_native_toolchain=True)
+        # Only configure LLVM, not build it because we just need
+        # LLVM CMake functionalities
+        shell.call(["env", self.toolchain.cmake, "-B", build_dir]
+                   + list(llvm_cmake.common_options(self))
+                   + list(cmake_options)
+                   + [llvm_source_dir])
+        return build_dir
+
+    def _build_stdlib(self, host_target, target_triple, llvm_cmake_dir):
         self.cmake_options.define('CMAKE_INSTALL_PREFIX:PATH', '/usr')
         self.cmake_options.define('CMAKE_BUILD_TYPE:STRING', self._build_variant)
+        # Teach about the WebAssembly target. UNIX is explicitly set to TRUE
+        # as CMake still doesn't recognize WASI as a UNIX platform and the
+        # variable is used in LLVM CMake configuration.
+        self.cmake_options.define('CMAKE_SYSTEM_NAME:STRING', 'WASI')
+        self.cmake_options.define('CMAKE_SYSTEM_PROCESSOR:STRING', 'wasm32')
+        self.cmake_options.define('UNIX:BOOL', 'TRUE')
         self.cmake_options.define(
             'SWIFT_STDLIB_BUILD_TYPE:STRING', self._build_variant)
 
@@ -69,9 +112,13 @@ def _build(self, host_target, target_triple):
         self.cmake_options.define('SWIFT_WASI_SYSROOT_PATH:STRING',
                                   self._wasi_sysroot_path(target_triple))
 
-        # It's ok to use the host LLVM build dir just for CMake functionalities
-        llvm_cmake_dir = os.path.join(self._host_llvm_build_dir(
-            host_target), 'lib', 'cmake', 'llvm')
+        # compiler-rt for WebAssembly target is not installed in the host toolchain
+        # so skip compiler health checks here.
+        self.cmake_options.define('CMAKE_C_COMPILER_WORKS:BOOL', 'TRUE')
+        self.cmake_options.define('CMAKE_CXX_COMPILER_WORKS:BOOL', 'TRUE')
+        self.cmake_options.define('CMAKE_Swift_COMPILER_WORKS:BOOL', 'TRUE')
+        self.cmake_options.define('LLVM_COMPILER_CHECKED:BOOL', 'TRUE')
+
         self.cmake_options.define('LLVM_DIR:PATH', llvm_cmake_dir)
 
         # Standalone stdlib configuration
@@ -88,6 +135,9 @@ def _build(self, host_target, target_triple):
         self.cmake_options.define('SWIFT_BUILD_STATIC_STDLIB:BOOL', 'TRUE')
         self.cmake_options.define('SWIFT_BUILD_DYNAMIC_STDLIB:BOOL', 'FALSE')
         self.cmake_options.define('SWIFT_BUILD_STATIC_SDK_OVERLAY:BOOL', 'TRUE')
+        # TODO: Turn off library evolution once we establish a good way to teach
+        # libraries including swift-testing whether to use the stable ABI.
+        self.cmake_options.define('SWIFT_STDLIB_STABLE_ABI:BOOL', 'TRUE')
         self.cmake_options.define('SWIFT_STDLIB_TRACING:BOOL', 'FALSE')
         self.cmake_options.define('SWIFT_STDLIB_HAS_ASLR:BOOL', 'FALSE')
         self.cmake_options.define('SWIFT_STDLIB_CONCURRENCY_TRACING:BOOL', 'FALSE')
@@ -198,7 +248,7 @@ def get_dependencies(cls):
 
 class WasmThreadsStdlib(WasmStdlib):
     def build(self, host_target):
-        self._build(host_target, 'wasm32-wasip1-threads')
+        self._build(host_target, 'wasm32-wasip1-threads', 'wasip1-threads-wasm32')
 
     def should_test_executable(self):
         # TODO(katei): Enable tests once WasmKit supports WASI threads