[build-script][tests] Add infrastucture to build/run tests on multiple targets.

Updates the build script, update checkout script, and lit config to
support cross compiling uswift, then using uswift to cross compile and
run tests on multiple targets locally.

Author: zoecarver

Swift.swiftdoc

@@ -2203,6 +2203,16 @@ if platform.system() != 'Darwin' or swift_test_mode == 'optimize_none_with_impli
 #
 
 config.substitutions.append(('%target-clangxx', '%s -std=c++11' % config.target_clang))
+config.substitutions.append(('%cxx-all-targets\(([^)]+)\)',
+                             SubstituteCaptures(r"%s -disable-legacy-type-info -enable-cxx-interop -I %s/uswift-macos-arm64/swift -target arm64-apple-macosx10.9 \1 && "
+                                                r"%s -disable-legacy-type-info -enable-cxx-interop -I %s/uswift-macos-x86_64/swift -target x86_64-apple-macosx10.9 \1 && "
+                                                r"%s -enable-cxx-interop -I %s/uswift-linux-armv7/swift -target armv7-unknown-linux-androideabi \1 &&"
+                                                r"%s -enable-cxx-interop -I %s/uswift-windows-x86_64/swift -target x86_64-unknown-windows-msvc \1 "
+                                                % (config.swift_frontend, shell_quote(os.path.realpath(swift_obj_root).replace("\\", "/")),
+                                                   config.swift_frontend, shell_quote(os.path.realpath(swift_obj_root).replace("\\", "/")),
+                                                   config.swift_frontend, shell_quote(os.path.realpath(swift_obj_root).replace("\\", "/")),
+                                                   config.swift_frontend, shell_quote(os.path.realpath(swift_obj_root).replace("\\", "/"))) )
+                           ))
 config.substitutions.append(('%target-swiftxx-frontend', '%s -enable-cxx-interop' % config.target_swift_frontend))
 
 config.substitutions.append(('%target-runtime', config.target_runtime))

Swift.swiftmodule

@@ -1245,6 +1245,7 @@ NINJA_SOURCE_DIR="${WORKSPACE}/ninja"
 SWIFT_SOURCE_DIR="${WORKSPACE}/swift"
 LLVM_SOURCE_DIR="${WORKSPACE}/llvm-project/llvm"
 CMARK_SOURCE_DIR="${WORKSPACE}/cmark"
+USWIFT_SOURCE_DIR="${WORKSPACE}/uswift"
 LLDB_SOURCE_DIR="${WORKSPACE}/llvm-project/lldb"
 LLBUILD_SOURCE_DIR="${WORKSPACE}/llbuild"
 STRESSTEST_PACKAGE_DIR="${WORKSPACE}/swift-stress-tester"
@@ -1266,6 +1267,7 @@ PRODUCTS=(llvm)
 [[ "${SKIP_BUILD_LIBCXX}" ]] || PRODUCTS+=(libcxx)
 [[ "${SKIP_BUILD_LIBICU}" ]] || PRODUCTS+=(libicu)
 [[ "${SKIP_BUILD_SWIFT}" ]] || PRODUCTS+=(swift)
+PRODUCTS+=(uswift)
 [[ "${SKIP_BUILD_LLDB}" ]] || PRODUCTS+=(lldb)
 [[ "${SKIP_BUILD_LIBDISPATCH}" ]] || PRODUCTS+=(libdispatch)
 [[ "${SKIP_BUILD_STATIC_LIBDISPATCH}" ]] || PRODUCTS+=(libdispatch_static)
@@ -1356,6 +1358,8 @@ function build_directory_bin() {
                 ;;
             libicu)
                 ;;
+            uswift)
+                ;;
             *)
                 echo "error: unknown product: ${product}"
                 exit 1
@@ -1759,6 +1763,91 @@ for host in "${ALL_HOSTS[@]}"; do
                 build_targets=(all)
                 ;;
 
+            uswift)
+                uswift_targets=(
+                    "macos-arm64" "arm64-apple-macosx10.9"
+                    "macos-x86_64" "x86_64-apple-macosx10.9"
+                    "linux-armv7" "armv7-unknown-linux-androideabi"
+                    "windows-x86_64" "x86_64-unknown-windows-msvc"
+                )
+                uswift_targets_length=${#uswift_targets[@]}
+
+                cmake_options=(
+                    "${cmake_options[@]}"
+                    -D BUILD_SHARED_LIBS=NO
+                    -D CMAKE_Swift_COMPILER_WORKS=YES
+                    -D CMAKE_BUILD_TYPE=Release
+                    -D CMAKE_Swift_COMPILER=$(build_directory ${host} swift)/bin/swiftc
+                )
+
+                # Build uswift for each target.
+                for (( i=1; i<${uswift_targets_length}+1; i+=2 ));
+                do
+                    uswift_target_name=${uswift_targets[$i-1]}
+                    uswift_target=${uswift_targets[$i]}
+                    all_cmake_options=(
+                        "${cmake_options[@]}"
+                        -D CMAKE_Swift_COMPILER_TARGET=${uswift_target}
+                    )
+
+                    if [[ "$uswift_target_name" == "windows-x86_64" ]] ; then
+                        all_cmake_options=(
+                            "${all_cmake_options[@]}"
+                            -D CMAKE_Swift_FLAGS="-use-ld=$(build_directory ${LOCAL_HOST} llvm)/bin/lld-link"
+                        )
+                    else
+                        all_cmake_options=(
+                            "${all_cmake_options[@]}"
+                            -D CMAKE_Swift_FLAGS="-Xfrontend -disable-legacy-type-info"
+                        )
+                    fi
+
+                    build_dir=$(build_directory ${uswift_target_name} ${product})
+
+                    generator_output_path=""
+                    if [[ "${CMAKE_GENERATOR}" == "Ninja" ]] ; then
+                        generator_output_path="${build_dir}/build.ninja"
+                    fi
+
+                    # Configure if necessary.
+                    cmake_cache_path="${build_dir}/CMakeCache.txt"
+                    if [[  "${RECONFIGURE}" || ! -f "${cmake_cache_path}" || \
+                                ( ! -z "${generator_output_path}" && ! -f "${generator_output_path}" ) ]] ; then
+                        call mkdir -p "${build_dir}"
+
+                        # Use `cmake-file-api` in case it is available.
+                        call mkdir -p "${build_dir}/.cmake/api/v1/query"
+                        call touch "${build_dir}/.cmake/api/v1/query/codemodel-v2" "${build_dir}/.cmake/api/v1/query/cache-v2"
+
+                        if [[ -n "${DISTCC}" ]]; then
+                            EXTRA_DISTCC_OPTIONS=("DISTCC_HOSTS=localhost,lzo,cpp")
+                        fi
+                        with_pushd "${build_dir}" \
+                            call env "${EXTRA_DISTCC_OPTIONS[@]}" "${CMAKE}" "${all_cmake_options[@]}" "${EXTRA_CMAKE_OPTIONS[@]}" "${source_dir}"
+                    fi
+
+                    # Note: unconditionally build uswift because it is required for running some tests.
+                    if [[ "${CMAKE_GENERATOR}" == "Xcode" ]] ; then
+                        # Xcode generator uses "ALL_BUILD" instead of "all".
+                        # Also, xcodebuild uses -target instead of bare names.
+                        build_targets=("${build_targets[@]/all/ALL_BUILD}")
+                        build_targets=("${build_targets[@]/#/${BUILD_TARGET_FLAG} }")
+
+                        # Xcode can't restart itself if it turns out we need to reconfigure.
+                        # Do an advance build to handle that.
+                        call "${CMAKE_BUILD[@]}" "${build_dir}" $(cmake_config_opt ${product})
+                    fi
+
+                    call "${CMAKE_BUILD[@]}" "${build_dir}" $(cmake_config_opt ${product}) -- "${BUILD_ARGS[@]}" ${build_targets[@]}
+
+                    # Copy over the uswift build.
+                    cp -a $(build_directory ${uswift_target_name} uswift) $(build_directory ${host} swift)
+                done
+
+                # We've already run cmake/build so we can just break out here.
+                continue
+                ;;
+
             llvm)
                 if [[ -n "${LLVM_NINJA_TARGETS_FOR_CROSS_COMPILE_HOSTS}" && $(is_cross_tools_host ${host}) ]] ; then
                     build_targets=("${LLVM_NINJA_TARGETS_FOR_CROSS_COMPILE_HOSTS[@]}")
@@ -1817,7 +1906,7 @@ for host in "${ALL_HOSTS[@]}"; do
                     "${llvm_cmake_options[@]}"
                 )
 
-                llvm_enable_projects=("clang")
+                llvm_enable_projects=("clang" "lld")
 
                 if [[ ! "${SKIP_BUILD_COMPILER_RT}" && ! $(is_cross_tools_host ${host}) ]]; then
                     llvm_enable_projects+=("compiler-rt")
@@ -1827,18 +1916,6 @@ for host in "${ALL_HOSTS[@]}"; do
                     llvm_enable_projects+=("clang-tools-extra")
                 fi
 
-                # On non-Darwin platforms, build lld so we can always have a
-                # linker that is compatible with the swift we are using to
-                # compile the stdlib.
-                #
-                # This makes it easier to build target stdlibs on systems that
-                # have old toolchains without more modern linker features.
-                if [[ "$(uname -s)" != "Darwin" ]] ; then
-                    if [[ ! "${SKIP_BUILD_LLD}" ]]; then
-                        llvm_enable_projects+=("lld")
-                    fi
-                fi
-
                 cmake_options+=(
                     -DLLVM_ENABLE_PROJECTS="$(join ";" ${llvm_enable_projects[@]})"
                 )
@@ -1898,7 +1975,6 @@ for host in "${ALL_HOSTS[@]}"; do
                 ;;
 
             swift)
-
                 if [[ "${ANDROID_API_LEVEL}" ]]; then
                     cmake_options=(
                         "${cmake_options[@]}"
@@ -2808,6 +2884,9 @@ for host in "${ALL_HOSTS[@]}"; do
             libcxx)
                 continue # We don't test libc++
                 ;;
+            uswift)
+                continue # We don't test uswift
+                ;;
             swift)
                 executable_target=
                 results_targets=
@@ -3159,6 +3238,9 @@ for host in "${ALL_HOSTS[@]}"; do
                 fi
                 INSTALL_TARGETS=install-swift-components
                 ;;
+            uswift)
+                continue
+                ;;
             llbuild)
                 if [[ -z "${INSTALL_LLBUILD}" ]] ; then
                     continue

Swift.swiftsourceinfo

@@ -346,7 +346,7 @@ def create_argument_parser():
            help='enable code coverage analysis in Swift (false, not-merged, '
                 'merged).')
 
-    option('--swift-disable-dead-stripping', toggle_true, 
+    option('--swift-disable-dead-stripping', toggle_true,
            help="Turn off Darwin-specific dead stripping for Swift host tools")
 
     option('--build-subdir', store,
@@ -1252,6 +1252,8 @@ def create_argument_parser():
            help='skip building llvm')
     option('--skip-build-swift', toggle_false('build_swift'),
            help='skip building swift')
+    option('--skip-build-uswift', toggle_false('build_uswift'),
+           help='skip building uswift')
 
     # We need to list --skip-test-swift explicitly because otherwise argparse
     # will auto-expand arguments like --skip-test-swift to the only known

test/lit.cfg

@@ -58,6 +58,7 @@
     'build_foundation': False,
     'build_cmark': True,
     'build_swift': True,
+    'build_uswift': True,
     'build_llvm': True,
     'build_freebsd': True,
     'build_ios': True,
@@ -597,6 +598,7 @@ class BuildScriptImplOption(_BaseOption):
     DisableOption('--skip-build-cmark', dest='build_cmark'),
     DisableOption('--skip-build-llvm', dest='build_llvm'),
     DisableOption('--skip-build-swift', dest='build_swift'),
+    DisableOption('--skip-build-uswift', dest='build_uswift'),
 
     DisableOption('--skip-build-android', dest='build_android'),
     DisableOption('--skip-build-benchmarks', dest='build_benchmarks'),

utils/build-script-impl

@@ -250,6 +250,7 @@ def convert_to_impl_arguments(self):
             (args.build_cmark, "cmark"),
             (args.build_llvm, "llvm"),
             (args.build_swift, "swift"),
+            (args.build_uswift, "uswift"),
             (args.build_foundation, "foundation"),
             (args.build_xctest, "xctest"),
             (args.build_lldb, "lldb"),
@@ -562,6 +563,8 @@ def compute_product_pipelines(self):
                                  is_enabled=self.args.build_libicu)
         builder.add_impl_product(products.Swift,
                                  is_enabled=self.args.build_swift)
+        builder.add_impl_product(products.USwift,
+                                 is_enabled=self.args.build_uswift)
         builder.add_impl_product(products.LLDB,
                                  is_enabled=self.args.build_lldb)
 

utils/build_swift/build_swift/driver_arguments.py

@@ -14,6 +14,7 @@
 from .benchmarks import Benchmarks
 from .cmark import CMark
 from .earlyswiftdriver import EarlySwiftDriver
+from .uswift import USwift
 from .foundation import Foundation
 from .indexstoredb import IndexStoreDB
 from .libcxx import LibCXX
@@ -40,6 +41,7 @@
 
 __all__ = [
     'BackDeployConcurrency',
+    'USwift',
     'CMark',
     'Ninja',
     'Foundation',

utils/build_swift/tests/expected_options.py

@@ -0,0 +1,28 @@
+# swift_build_support/products/cmark.py -------------------------*- python -*-
+#
+# This source file is part of the Swift.org open source project
+#
+# Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
+# Licensed under Apache License v2.0 with Runtime Library Exception
+#
+# See https://swift.org/LICENSE.txt for license information
+# See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+#
+# ----------------------------------------------------------------------------
+
+from . import product
+
+
+class USwift(product.Product):
+    @classmethod
+    def is_build_script_impl_product(cls):
+        """is_build_script_impl_product -> bool
+
+        Whether this product is produced by build-script-impl.
+        """
+        return True
+
+    # This is the root of the build-graph, so it doesn't have any dependencies.
+    @classmethod
+    def get_dependencies(cls):
+        return []