#!/usr/bin/env bash
#===----------------------------------------------------------------------===##
#
# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
# See https://llvm.org/LICENSE.txt for license information.
# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#
#===----------------------------------------------------------------------===##

set -ex
set -o pipefail
unset LANG
unset LC_ALL
unset LC_COLLATE

PROGNAME="$(basename "${0}")"

function usage() {
cat <<EOF
Usage:
${PROGNAME} [options] <BUILDER>

[-h|--help]         Display this help and exit.

--llvm-root <DIR>   Path to the root of the LLVM monorepo. By default, we try
                    to figure it out based on the current working directory.

--build-dir <DIR>   The directory to use for building the library. By default,
                    this is '<llvm-root>/build/<builder>'.

--osx-roots <DIR>   Path to pre-downloaded macOS dylibs. By default, we download
                    them from Green Dragon. This is only relevant at all when
                    running back-deployment testing if one wants to override
                    the old dylibs we use to run the tests with different ones.
Environment variables
CC                  The C compiler to use, this value is used by CMake. This
                    variable is optional.

CXX                 The C++ compiler to use, this value is used by CMake. This
                    variable is optional.

CMAKE               The CMake binary to use. This variable is optional.

CLANG_FORMAT        The clang-format binary to use when generating the format
                    ignore list.

GIT_CLANG_FORMAT    The git-clang-format binary to use in the 'format' builder.
                    When the value is omitted, it defaults to
                    'git-clang-format'. This variable or its fallback must work
                    when running the 'format' builder.

ENABLE_CLANG_TIDY   Whether to compile and run clang-tidy checks. This variable
                    is optional.
EOF
}

if [[ $# == 0 ]]; then
   usage
   exit 0
fi

while [[ $# -gt 0 ]]; do
    case ${1} in
        -h|--help)
            usage
            exit 0
            ;;
        --llvm-root)
            MONOREPO_ROOT="${2}"
            shift; shift
            ;;
        --build-dir)
            BUILD_DIR="${2}"
            shift; shift
            ;;
        --osx-roots)
            OSX_ROOTS="${2}"
            shift; shift
            ;;
        *)
            BUILDER="${1}"
            shift
            ;;
    esac
done

MONOREPO_ROOT="${MONOREPO_ROOT:="$(git rev-parse --show-toplevel)"}"
BUILD_DIR="${BUILD_DIR:=${MONOREPO_ROOT}/build/${BUILDER}}"
INSTALL_DIR="${BUILD_DIR}/install"

# If we can find Ninja/CMake provided by Xcode, use those since we know their
# version will generally work with the Clang shipped in Xcode (e.g. if Clang
# knows about -std=c++20, the CMake bundled in Xcode will probably know about
# that flag too).
if xcrun --find ninja &>/dev/null; then
    NINJA="$(xcrun --find ninja)"
elif which ninja &>/dev/null; then
    # The current implementation of modules needs the absolute path to the ninja
    # binary.
    # TODO MODULES Is this still needed when CMake has libc++ module support?
    NINJA="$(which ninja)"
else
    NINJA="ninja"
fi

if [ -z "${CMAKE}" ]; then
    if xcrun --find cmake &>/dev/null; then
        CMAKE="$(xcrun --find cmake)"
    else
        CMAKE="cmake"
    fi
fi

function clean() {
    rm -rf "${BUILD_DIR}"
}

if [ -z "${ENABLE_CLANG_TIDY}" ]; then
    ENABLE_CLANG_TIDY=Off
fi

function generate-cmake-base() {
    echo "--- Generating CMake"
    ${CMAKE} \
          -S "${MONOREPO_ROOT}/runtimes" \
          -B "${BUILD_DIR}" \
          -GNinja -DCMAKE_MAKE_PROGRAM="${NINJA}" \
          -DCMAKE_BUILD_TYPE=RelWithDebInfo \
          -DCMAKE_INSTALL_PREFIX="${INSTALL_DIR}" \
          -DLIBCXX_ENABLE_WERROR=YES \
          -DLIBCXXABI_ENABLE_WERROR=YES \
          -DLIBUNWIND_ENABLE_WERROR=YES \
          -DLIBCXX_ENABLE_CLANG_TIDY=${ENABLE_CLANG_TIDY} \
          -DLLVM_LIT_ARGS="-sv --show-unsupported --xunit-xml-output test-results.xml --timeout=1500 --time-tests" \
          "${@}"
}

function generate-cmake() {
    generate-cmake-base \
          -DLLVM_ENABLE_RUNTIMES="libcxx;libcxxabi;libunwind" \
          -DLIBCXX_CXX_ABI=libcxxabi \
          "${@}"
}

function generate-cmake-libcxx-win() {
    generate-cmake-base \
          -DLLVM_ENABLE_RUNTIMES="libcxx" \
          -DCMAKE_C_COMPILER=clang-cl \
          -DCMAKE_CXX_COMPILER=clang-cl \
          "${@}"
}

function check-runtimes() {
    echo "--- Installing libc++, libc++abi and libunwind to a fake location"
    ${NINJA} -vC "${BUILD_DIR}" install-cxx install-cxxabi install-unwind

    echo "+++ Running the libc++ tests"
    ${NINJA} -vC "${BUILD_DIR}" check-cxx

    echo "+++ Running the libc++abi tests"
    ${NINJA} -vC "${BUILD_DIR}" check-cxxabi

    echo "+++ Running the libunwind tests"
    ${NINJA} -vC "${BUILD_DIR}" check-unwind
}

# TODO: The goal is to test this against all configurations. We should also move
#       this to the Lit test suite instead of being a separate CMake target.
function check-abi-list() {
    echo "+++ Running the libc++ ABI list test"
    ${NINJA} -vC "${BUILD_DIR}" check-cxx-abilist || (
        echo "+++ Generating the libc++ ABI list after failed check"
        ${NINJA} -vC "${BUILD_DIR}" generate-cxx-abilist
        false
    )
}

function check-cxx-benchmarks() {
    echo "--- Running the benchmarks"
    ${NINJA} -vC "${BUILD_DIR}" check-cxx-benchmarks
}

# Print the version of a few tools to aid diagnostics in some cases
${CMAKE} --version
${NINJA} --version

if [ ! -z "${CXX}" ]; then ${CXX} --version; fi

case "${BUILDER}" in
check-format)
    clean
    echo "+++ Checking formatting"
    # We need to set --extensions so that clang-format checks extensionless files.
    mkdir -p ${BUILD_DIR}
    if [ -z "${GIT_CLANG_FORMAT}" ]; then
       GIT_CLANG_FORMAT=git-clang-format
    fi
    ${GIT_CLANG_FORMAT} \
        --diff \
        --extensions ',h,hpp,c,cpp,cppm,inc,ipp' HEAD~1 \
        -- $(find libcxx/{benchmarks,include,modules,src} -type f | grep -vf libcxx/utils/data/ignore_format.txt) \
        | tee ${BUILD_DIR}/clang-format.patch
    # Check if the diff is empty, fail otherwise.
    ! grep -q '^--- a' ${BUILD_DIR}/clang-format.patch
;;
check-generated-output)
    # `! foo` doesn't work properly with `set -e`, use `! foo || false` instead.
    # https://stackoverflow.com/questions/57681955/set-e-does-not-respect-logical-not
    clean
    generate-cmake

    # Reject patches that forgot to re-run the generator scripts.
    echo "+++ Making sure the generator scripts were run"
    ${NINJA} -vC "${BUILD_DIR}" libcxx-generate-files
    git diff | tee ${BUILD_DIR}/generated_output.patch
    git ls-files -o --exclude-standard | tee ${BUILD_DIR}/generated_output.status
    ! grep -q '^--- a' ${BUILD_DIR}/generated_output.patch || false
    if [ -s ${BUILD_DIR}/generated_output.status ]; then
        echo "It looks like not all the generator scripts were run,"
        echo "did you forget to build the libcxx-generate-files target?"
        echo "Did you add all new files it generated?"
        false
    fi

    ${MONOREPO_ROOT}/libcxx/utils/generate_ignore_format.sh
    git diff | tee ${BUILD_DIR}/generated_output.patch
    git ls-files -o --exclude-standard | tee ${BUILD_DIR}/generated_output.status
    ! grep -q '^--- a' ${BUILD_DIR}/generated_output.patch || false
    if [ -s ${BUILD_DIR}/generated_output.status ]; then
        echo "It looks like the list of not formatted files has changed."
        echo "If a file is now properly formatted with clang-format, remove the file name from "
        echo "libcxx/utils/data/ignore_format.txt. Otherwise you have to fix the"
        echo "formatting of some of the changed files."
        false
    fi

    # Reject patches that introduce non-ASCII characters or hard tabs.
    # Depends on LC_COLLATE set at the top of this script.
    ! grep -rn '[^ -~]' libcxx/include libcxx/src libcxx/test libcxx/benchmarks \
           --exclude '*.dat' \
           --exclude '*unicode*.cpp' \
           --exclude '*print*.sh.cpp' \
           --exclude 'escaped_output.*.pass.cpp' \
           --exclude 'format_tests.h' \
           --exclude 'format.functions.tests.h' \
           --exclude 'formatter.*.pass.cpp' \
           --exclude 'grep.pass.cpp' \
           --exclude 'locale-specific_form.pass.cpp' \
           --exclude 'ostream.pass.cpp' \
           --exclude 'transcoding.pass.cpp' \
           --exclude 'underflow.pass.cpp' \
           || false

    # Reject code with trailing whitespace
    ! grep -rn '[[:blank:]]$' libcxx/include libcxx/src libcxx/test libcxx/benchmarks || false
;;
#
# Various Standard modes
#
generic-cxx03)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-cxx03.cmake"
    check-runtimes
    check-abi-list
;;
generic-cxx11)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-cxx11.cmake"
    check-runtimes
    check-abi-list
;;
generic-cxx14)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-cxx14.cmake"
    check-runtimes
    check-abi-list
;;
generic-cxx17)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-cxx17.cmake"
    check-runtimes
    check-abi-list
;;
generic-cxx20)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-cxx20.cmake"
    check-runtimes
    check-abi-list
;;
generic-cxx23)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-cxx23.cmake"
    check-runtimes
    check-abi-list
;;
generic-cxx26)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-cxx26.cmake"
    check-runtimes
    check-abi-list
;;
#
# Other compiler support
#
generic-gcc)
    clean
    generate-cmake -DLIBCXX_ENABLE_WERROR=NO \
                   -DLIBCXXABI_ENABLE_WERROR=NO \
                   -DLIBUNWIND_ENABLE_WERROR=NO
    check-runtimes
;;
generic-gcc-cxx11)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-cxx11.cmake" \
                   -DLIBCXX_ENABLE_WERROR=NO \
                   -DLIBCXXABI_ENABLE_WERROR=NO \
                   -DLIBUNWIND_ENABLE_WERROR=NO
    check-runtimes
;;
#
# Sanitizers
#
generic-asan)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-asan.cmake"
    check-runtimes
;;
generic-msan)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-msan.cmake"
    check-runtimes
;;
generic-tsan)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-tsan.cmake"
    check-runtimes
;;
generic-ubsan)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-ubsan.cmake"
    check-runtimes
;;
#
# Various build configurations
#
bootstrapping-build)
    clean

    echo "--- Generating CMake"
    ${CMAKE} \
          -S "${MONOREPO_ROOT}/llvm" \
          -B "${BUILD_DIR}" \
          -GNinja -DCMAKE_MAKE_PROGRAM="${NINJA}" \
          -DCMAKE_CXX_COMPILER_LAUNCHER="ccache" \
          -DCMAKE_BUILD_TYPE=RelWithDebInfo \
          -DCMAKE_INSTALL_PREFIX="${INSTALL_DIR}" \
          -DLLVM_ENABLE_PROJECTS="clang" \
          -DLLVM_ENABLE_RUNTIMES="libcxx;libcxxabi;libunwind" \
          -DLLVM_RUNTIME_TARGETS="$(${CXX} --print-target-triple)" \
          -DLLVM_TARGETS_TO_BUILD="host" \
          -DRUNTIMES_BUILD_ALLOW_DARWIN=ON \
          -DLLVM_ENABLE_ASSERTIONS=ON

    echo "+++ Running the libc++ and libc++abi tests"
    ${NINJA} -C "${BUILD_DIR}" check-runtimes

    echo "--- Installing libc++ and libc++abi to a fake location"
    ${NINJA} -C "${BUILD_DIR}" install-runtimes

    ccache -s
;;
generic-static)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-static.cmake"
    check-runtimes
;;
generic-merged)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-merged.cmake" \
                   -DLIBCXX_TEST_CONFIG="llvm-libc++-shared.cfg.in" \
                   -DLIBCXXABI_TEST_CONFIG="llvm-libc++abi-merged.cfg.in" \
                   -DLIBUNWIND_TEST_CONFIG="llvm-libunwind-merged.cfg.in"
    check-runtimes
;;
generic-hardened-mode)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-hardened-mode.cmake"
    check-runtimes
    check-abi-list
;;
generic-debug-mode)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-debug-mode.cmake"
    check-runtimes
    check-abi-list
;;
generic-with_llvm_unwinder)
    clean
    generate-cmake -DLIBCXXABI_USE_LLVM_UNWINDER=ON
    check-runtimes
;;
#
# Module builds
#
generic-modules)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-modules.cmake"
    check-runtimes
    check-abi-list
;;
generic-modules-lsv)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-modules-lsv.cmake"
    check-runtimes
    check-abi-list
;;
generic-module-std-cxx23)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-module-std-cxx23.cmake"
    check-runtimes
    check-abi-list
;;
#
# Parts removed
#
generic-no-threads)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-no-threads.cmake"
    check-runtimes
;;
generic-no-filesystem)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-no-filesystem.cmake"
    check-runtimes
;;
generic-no-random_device)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-no-random_device.cmake"
    check-runtimes
;;
generic-no-localization)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-no-localization.cmake"
    check-runtimes
;;
generic-no-unicode)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-no-unicode.cmake"
    check-runtimes
;;
generic-no-wide-characters)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-no-wide-characters.cmake"
    check-runtimes
;;
generic-no-experimental)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-no-experimental.cmake"
    check-runtimes
    check-abi-list
;;
generic-no-exceptions)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-no-exceptions.cmake"
    check-runtimes
    check-abi-list
;;
#
# Other miscellaneous jobs
#
generic-abi-unstable)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-abi-unstable.cmake"
    check-runtimes
;;
apple-system)
    clean

    arch="$(uname -m)"
    xcrun --sdk macosx                                              \
        ${MONOREPO_ROOT}/libcxx/utils/ci/apple-install-libcxx.sh    \
            --llvm-root ${MONOREPO_ROOT}                            \
            --build-dir ${BUILD_DIR}                                \
            --install-dir ${INSTALL_DIR}                            \
            --symbols-dir "${BUILD_DIR}/symbols"                    \
            --architectures "${arch}"                               \
            --version "999.99"

    # TODO: It would be better to run the tests against the fake-installed version of libc++ instead
    xcrun --sdk macosx ninja -vC "${BUILD_DIR}/${arch}" check-cxx check-cxxabi check-cxx-abilist
;;
apple-system-backdeployment-hardened-*)
    clean

    if [[ "${OSX_ROOTS}" == "" ]]; then
        echo "--- Downloading previous macOS dylibs"
        PREVIOUS_DYLIBS_URL="https://dl.dropboxusercontent.com/s/gmcfxwgl9f9n6pu/libcxx-roots.tar.gz"
        OSX_ROOTS="${BUILD_DIR}/macos-roots"
        mkdir -p "${OSX_ROOTS}"
        curl "${PREVIOUS_DYLIBS_URL}" | tar -xz --strip-components=1 -C "${OSX_ROOTS}"
    fi

    DEPLOYMENT_TARGET="${BUILDER#apple-system-backdeployment-hardened-}"

    # TODO: On Apple platforms, we never produce libc++abi.1.dylib or libunwind.1.dylib,
    #       only libc++abi.dylib and libunwind.dylib. Fix that in the build so that the
    #       tests stop searching for @rpath/libc++abi.1.dylib and @rpath/libunwind.1.dylib.
    cp "${OSX_ROOTS}/macOS/libc++abi/${DEPLOYMENT_TARGET}/libc++abi.dylib" \
       "${OSX_ROOTS}/macOS/libc++abi/${DEPLOYMENT_TARGET}/libc++abi.1.dylib"
    cp "${OSX_ROOTS}/macOS/libunwind/${DEPLOYMENT_TARGET}/libunwind.dylib" \
       "${OSX_ROOTS}/macOS/libunwind/${DEPLOYMENT_TARGET}/libunwind.1.dylib"

    arch="$(uname -m)"
    PARAMS="target_triple=${arch}-apple-macosx${DEPLOYMENT_TARGET}"
    PARAMS+=";cxx_runtime_root=${OSX_ROOTS}/macOS/libc++/${DEPLOYMENT_TARGET}"
    PARAMS+=";abi_runtime_root=${OSX_ROOTS}/macOS/libc++abi/${DEPLOYMENT_TARGET}"
    PARAMS+=";unwind_runtime_root=${OSX_ROOTS}/macOS/libunwind/${DEPLOYMENT_TARGET}"
    PARAMS+=";hardening_mode=hardened"

    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Apple.cmake" \
                   -DLIBCXX_TEST_CONFIG="apple-libc++-backdeployment.cfg.in" \
                   -DLIBCXXABI_TEST_CONFIG="apple-libc++abi-backdeployment.cfg.in" \
                   -DLIBUNWIND_TEST_CONFIG="apple-libunwind-backdeployment.cfg.in" \
                   -DLIBCXX_TEST_PARAMS="${PARAMS}" \
                   -DLIBCXXABI_TEST_PARAMS="${PARAMS}" \
                   -DLIBUNWIND_TEST_PARAMS="${PARAMS}"

    check-runtimes
;;
apple-system-backdeployment-*)
    clean

    if [[ "${OSX_ROOTS}" == "" ]]; then
        echo "--- Downloading previous macOS dylibs"
        PREVIOUS_DYLIBS_URL="https://dl.dropboxusercontent.com/s/gmcfxwgl9f9n6pu/libcxx-roots.tar.gz"
        OSX_ROOTS="${BUILD_DIR}/macos-roots"
        mkdir -p "${OSX_ROOTS}"
        curl "${PREVIOUS_DYLIBS_URL}" | tar -xz --strip-components=1 -C "${OSX_ROOTS}"
    fi

    DEPLOYMENT_TARGET="${BUILDER#apple-system-backdeployment-}"

    # TODO: On Apple platforms, we never produce libc++abi.1.dylib or libunwind.1.dylib,
    #       only libc++abi.dylib and libunwind.dylib. Fix that in the build so that the
    #       tests stop searching for @rpath/libc++abi.1.dylib and @rpath/libunwind.1.dylib.
    cp "${OSX_ROOTS}/macOS/libc++abi/${DEPLOYMENT_TARGET}/libc++abi.dylib" \
       "${OSX_ROOTS}/macOS/libc++abi/${DEPLOYMENT_TARGET}/libc++abi.1.dylib"
    cp "${OSX_ROOTS}/macOS/libunwind/${DEPLOYMENT_TARGET}/libunwind.dylib" \
       "${OSX_ROOTS}/macOS/libunwind/${DEPLOYMENT_TARGET}/libunwind.1.dylib"

    arch="$(uname -m)"
    PARAMS="target_triple=${arch}-apple-macosx${DEPLOYMENT_TARGET}"
    PARAMS+=";cxx_runtime_root=${OSX_ROOTS}/macOS/libc++/${DEPLOYMENT_TARGET}"
    PARAMS+=";abi_runtime_root=${OSX_ROOTS}/macOS/libc++abi/${DEPLOYMENT_TARGET}"
    PARAMS+=";unwind_runtime_root=${OSX_ROOTS}/macOS/libunwind/${DEPLOYMENT_TARGET}"

    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Apple.cmake" \
                   -DLIBCXX_TEST_CONFIG="apple-libc++-backdeployment.cfg.in" \
                   -DLIBCXXABI_TEST_CONFIG="apple-libc++abi-backdeployment.cfg.in" \
                   -DLIBUNWIND_TEST_CONFIG="apple-libunwind-backdeployment.cfg.in" \
                   -DLIBCXX_TEST_PARAMS="${PARAMS}" \
                   -DLIBCXXABI_TEST_PARAMS="${PARAMS}" \
                   -DLIBUNWIND_TEST_PARAMS="${PARAMS}"

    check-runtimes
;;
benchmarks)
    clean
    generate-cmake
    check-cxx-benchmarks
;;
documentation)
    clean
    generate-cmake -DLLVM_ENABLE_SPHINX=ON

    echo "+++ Generating documentation"
    ${NINJA} -vC "${BUILD_DIR}" docs-libcxx-html
;;
aarch64)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/AArch64.cmake"
    check-runtimes
;;
aarch64-no-exceptions)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/AArch64.cmake" \
                   -DLIBCXX_ENABLE_EXCEPTIONS=OFF \
                   -DLIBCXXABI_ENABLE_EXCEPTIONS=OFF
    check-runtimes
;;
# Aka Armv8 32 bit
armv8)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Armv8Arm.cmake"
    check-runtimes
;;
armv8-no-exceptions)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Armv8Thumb-no-exceptions.cmake"
    check-runtimes
;;
# Armv7 32 bit. One building Arm only one Thumb only code.
armv7)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Armv7Arm.cmake"
    check-runtimes
;;
armv7-no-exceptions)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Armv7Thumb-no-exceptions.cmake"
    check-runtimes
;;
clang-cl-dll)
    clean
    # TODO: Currently, building with the experimental library breaks running
    # tests (the test linking look for the c++experimental library with the
    # wrong name, and the statically linked c++experimental can't be linked
    # correctly when libc++ visibility attributes indicate dllimport linkage
    # anyway), thus just disable the experimental library. Remove this
    # setting when cmake and the test driver does the right thing automatically.
    generate-cmake-libcxx-win -DLIBCXX_TEST_PARAMS="enable_experimental=False"
    echo "+++ Running the libc++ tests"
    ${NINJA} -vC "${BUILD_DIR}" check-cxx
;;
clang-cl-static)
    clean
    generate-cmake-libcxx-win -DLIBCXX_ENABLE_SHARED=OFF
    echo "+++ Running the libc++ tests"
    ${NINJA} -vC "${BUILD_DIR}" check-cxx
;;
clang-cl-no-vcruntime)
    clean
    # Building libc++ in the same way as in clang-cl-dll above, but running
    # tests with -D_HAS_EXCEPTIONS=0, which users might set in certain
    # translation units while using libc++, even if libc++ is built with
    # exceptions enabled.
    generate-cmake-libcxx-win -DLIBCXX_TEST_PARAMS="enable_experimental=False" \
                              -DLIBCXX_TEST_CONFIG="llvm-libc++-shared-no-vcruntime-clangcl.cfg.in"
    echo "+++ Running the libc++ tests"
    ${NINJA} -vC "${BUILD_DIR}" check-cxx
;;
clang-cl-debug)
    clean
    generate-cmake-libcxx-win -DLIBCXX_TEST_PARAMS="enable_experimental=False" \
                              -DCMAKE_BUILD_TYPE=Debug
    echo "+++ Running the libc++ tests"
    ${NINJA} -vC "${BUILD_DIR}" check-cxx
;;
clang-cl-static-crt)
    clean
    # Test linking a static libc++ with the static CRT ("MultiThreaded" denotes
    # the static CRT, as opposed to "MultiThreadedDLL" which is the default).
    generate-cmake-libcxx-win -DLIBCXX_ENABLE_SHARED=OFF \
                              -DCMAKE_MSVC_RUNTIME_LIBRARY=MultiThreaded
    echo "+++ Running the libc++ tests"
    ${NINJA} -vC "${BUILD_DIR}" check-cxx
;;
mingw-dll)
    clean
    # Explicitly specify the compiler with a triple prefix. The CI
    # environment has got two installations of Clang; the default one
    # defaults to MSVC mode, while there's an installation of llvm-mingw
    # further back in PATH. By calling the compiler with an explicit
    # triple prefix, we use the one that is bundled with a mingw sysroot.
    generate-cmake \
          -DCMAKE_C_COMPILER=x86_64-w64-mingw32-clang \
          -DCMAKE_CXX_COMPILER=x86_64-w64-mingw32-clang++ \
          -C "${MONOREPO_ROOT}/libcxx/cmake/caches/MinGW.cmake"
    check-runtimes
;;
mingw-static)
    clean
    generate-cmake \
          -DCMAKE_C_COMPILER=x86_64-w64-mingw32-clang \
          -DCMAKE_CXX_COMPILER=x86_64-w64-mingw32-clang++ \
          -C "${MONOREPO_ROOT}/libcxx/cmake/caches/MinGW.cmake" \
          -DLIBCXX_ENABLE_SHARED=OFF \
          -DLIBUNWIND_ENABLE_SHARED=OFF
    check-runtimes
;;
mingw-dll-i686)
    clean
    generate-cmake \
          -DCMAKE_C_COMPILER=i686-w64-mingw32-clang \
          -DCMAKE_CXX_COMPILER=i686-w64-mingw32-clang++ \
          -C "${MONOREPO_ROOT}/libcxx/cmake/caches/MinGW.cmake"
    check-runtimes
;;
aix)
    clean
    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/AIX.cmake" \
                   -DLIBCXX_TEST_CONFIG="ibm-libc++-shared.cfg.in" \
                   -DLIBCXXABI_TEST_CONFIG="ibm-libc++abi-shared.cfg.in" \
                   -DLIBUNWIND_TEST_CONFIG="ibm-libunwind-shared.cfg.in"
    check-abi-list
    check-runtimes
;;
#################################################################
# Insert vendor-specific internal configurations below.
#
# This allows vendors to extend this file with their own internal
# configurations without running into merge conflicts with upstream.
#################################################################

#################################################################
*)
    echo "${BUILDER} is not a known configuration"
    exit 1
;;
esac