#!/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>'.
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="${2}"
            shift; shift
            ;;
        *)
            BUILDER="${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"

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

# Print the version of a few tools to aid diagnostics in some cases
cmake --version
ninja --version

case "${BUILDER}" in
check-format)
    echo "*** Checking for trailing whitespace left in Clang source files ***"
    if grep -rnI '[[:blank:]]$' clang/lib clang/include clang/docs; then
        echo "*** Trailing whitespace has been found in Clang source files as described above ***"
        exit 1
    fi
;;
build-clang)
    mkdir install
    # We use Release here to avoid including debug information. Otherwise, the
    # clang binary is very large, which is problematic because we need to upload
    # the artifacts for other jobs to use. This may seem like nothing, but with
    # the number of jobs we run daily, this can result in thousands of GB of
    # network I/O.
    cmake                                                                      \
        -S llvm                                                                \
        -B ${BUILD_DIR}                                                        \
        -G Ninja                                                               \
        -DCMAKE_CXX_COMPILER_LAUNCHER="ccache"                                 \
        -DCMAKE_BUILD_TYPE=Release                                             \
        -DCMAKE_INSTALL_PREFIX=install                                         \
        -DLLVM_ENABLE_PROJECTS="clang;compiler-rt"                             \

    ninja -C ${BUILD_DIR} install-clang install-clang-resource-headers
    ccache -s
    tar -cJvf install.tar.xz install/
    buildkite-agent artifact upload --debug install.tar.xz

    ninja -C ${BUILD_DIR} check-clang
;;
build-clang-windows)
    cmake -S llvm -B ${BUILD_DIR} -G Ninja                                      \
        -D CMAKE_C_COMPILER_LAUNCHER=sccache                                    \
        -D CMAKE_CXX_COMPILER_LAUNCHER=sccache                                  \
        -D CMAKE_BUILD_TYPE=Release                                             \
        -D CMAKE_INSTALL_PREFIX=install-windows                                 \
        -D LLVM_ENABLE_PROJECTS="clang;compiler-rt"                             \
        -D LLVM_ENABLE_ASSERTIONS=ON                                            \
        -D LLVM_BUILD_EXAMPLES=ON                                               \
        -D COMPILER_RT_BUILD_LIBFUZZER=OFF                                      \
        -D COMPILER_RT_BUILD_ORC=OFF

    ninja -C ${BUILD_DIR} install-clang install-clang-resource-headers
    ninja -C ${BUILD_DIR} check-clang
;;
generic-cxx03)
    buildkite-agent artifact download install.tar.xz .
    tar -xvf install.tar.xz
    export CC=$(pwd)/install/bin/clang
    export CXX=$(pwd)/install/bin/clang++
    chmod +x install/bin/clang install/bin/clang++

    clean
    cmake -S "${MONOREPO_ROOT}/runtimes" -B "${BUILD_DIR}" -GNinja \
          -DLLVM_ENABLE_RUNTIMES="libcxx;libcxxabi;libunwind" \
          -DLIBCXX_CXX_ABI=libcxxabi \
          -DCMAKE_BUILD_TYPE=RelWithDebInfo \
          -DCMAKE_INSTALL_PREFIX="${INSTALL_DIR}" \
          -DLIBCXX_TEST_PARAMS="std=c++03" \
          -DLIBCXXABI_TEST_PARAMS="std=c++03"

    ninja -vC "${BUILD_DIR}" check-runtimes
;;
generic-cxx26)
    buildkite-agent artifact download install.tar.xz .
    tar -xvf install.tar.xz
    export CC=$(pwd)/install/bin/clang
    export CXX=$(pwd)/install/bin/clang++
    chmod +x install/bin/clang install/bin/clang++

    clean
    cmake -S "${MONOREPO_ROOT}/runtimes" -B "${BUILD_DIR}" -GNinja \
          -DLLVM_ENABLE_RUNTIMES="libcxx;libcxxabi;libunwind" \
          -DLIBCXX_CXX_ABI=libcxxabi \
          -DCMAKE_BUILD_TYPE=RelWithDebInfo \
          -DCMAKE_INSTALL_PREFIX="${INSTALL_DIR}" \
          -DLIBCXX_TEST_PARAMS="std=c++26" \
          -DLIBCXXABI_TEST_PARAMS="std=c++26"

    ninja -vC "${BUILD_DIR}" check-runtimes
;;
generic-modules)
    buildkite-agent artifact download install.tar.xz .
    tar -xvf install.tar.xz
    export CC=$(pwd)/install/bin/clang
    export CXX=$(pwd)/install/bin/clang++
    chmod +x install/bin/clang install/bin/clang++

    clean
    cmake -S "${MONOREPO_ROOT}/runtimes" -B "${BUILD_DIR}" -GNinja \
          -DLLVM_ENABLE_RUNTIMES="libcxx;libcxxabi;libunwind" \
          -DLIBCXX_CXX_ABI=libcxxabi \
          -DCMAKE_BUILD_TYPE=RelWithDebInfo \
          -DCMAKE_INSTALL_PREFIX="${INSTALL_DIR}" \
          -DLIBCXX_TEST_PARAMS="enable_modules=clang" \
          -DLIBCXXABI_TEST_PARAMS="enable_modules=clang"

    ninja -vC "${BUILD_DIR}" 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