# Maintainer: Evangelos Foutras <foutrelis@archlinux.org>
# Contributor: Jan "heftig" Steffens <jan.steffens@gmail.com>

pkgname=('llvm' 'llvm-libs')
pkgver=22.1.8
pkgrel=2
arch=('x86_64')
url="https://llvm.org/"
license=('Apache-2.0 WITH LLVM-exception')
makedepends=('cmake' 'ninja' 'zlib' 'zstd' 'curl' 'libffi' 'libedit' 'libxml2'
             'python-setuptools' 'python-psutil' 'python-sphinx'
             'python-myst-parser' 'python-build' 'python-installer' 'python-wheel'
             'clang' 'lld' 'llvm')
checkdepends=('llvm-libs')
options=('staticlibs' '!lto') # tools/llvm-shlib/typeids.test fails with LTO
_source_base=https://github.com/llvm/llvm-project/releases/download/llvmorg-$pkgver
source=($_source_base/llvm-project-$pkgver.src.tar.xz{,.sig})
sha256sums=('922f1817a0df7b1489272d18134ee0087a8b068828f87ac63b9861b1a9965888'
            'SKIP')
validpgpkeys=('474E22316ABF4785A88C6E8EA2C794A986419D8A'  # Tom Stellard <tstellar@redhat.com>
              'D574BD5D1D0E98895E3BF90044F2485E45D59042'  # Tobias Hieta <tobias@hieta.se>
              'FFB3368980F3E6BB5737145A316C56D064CACBA5'  # Douglas Yung <douglas.yung@sony.com>
              '71046D1E9C6656BDD61171873E83BABF4A4F9E85'  # Cullen Rhodes <cullen.rhodes@arm.com>
)

# Utilizing LLVM_DISTRIBUTION_COMPONENTS to avoid
# installing static libraries; inspired by Gentoo
_get_distribution_components() {
  local target
  ninja -t targets | grep -Po 'install-\K.*(?=-stripped:)' | while read -r target; do
    case $target in
      llvm-libraries|distribution)
        continue
        ;;
      # shared libraries
      LLVM|LLVMgold)
        ;;
      # libraries needed for clang-tblgen
      LLVMDemangle|LLVMSupport|LLVMTableGen)
        ;;
      # used by lldb
      LLVMDebuginfod)
        ;;
      # testing libraries
      LLVMTestingAnnotations|LLVMTestingSupport)
        ;;
      # exclude static libraries
      LLVM*)
        continue
        ;;
      # exclude llvm-exegesis (doesn't seem useful without libpfm)
      llvm-exegesis)
        continue
        ;;
    esac
    echo $target
  done
}

prepare() {
  cd llvm-project-$pkgver.src/llvm
  mkdir build

  # Remove CMake find module for zstd; breaks if out of sync with upstream zstd
  rm cmake/modules/Findzstd.cmake
}

build() {
  cd llvm-project-$pkgver.src/llvm/build

  # Build only minimal debug info to reduce size
  CFLAGS=${CFLAGS/-g /-g1 }
  CXXFLAGS=${CXXFLAGS/-g /-g1 }

  # Add fno-semantic-position, can improve at fPIC compiled packages massively the performance
  # At clang it improves for 3%
  # If clang is as compiler used, it should as default add this anyways
  export CFLAGS+=" -fno-semantic-interposition"
  export CXXFLAGS+=" -fno-semantic-interposition"

  local cmake_args=(
    -G Ninja
    -DCMAKE_BUILD_TYPE=Release
    -DCMAKE_INSTALL_DOCDIR=share/doc
    -DCMAKE_INSTALL_PREFIX=/usr
    -DCMAKE_SKIP_RPATH=ON
    -DLLVM_BINUTILS_INCDIR=/usr/include
    -DLLVM_BUILD_DOCS=ON
    -DLLVM_BUILD_LLVM_DYLIB=ON
    -DLLVM_BUILD_TESTS=ON
    -DLLVM_ENABLE_BINDINGS=OFF
    -DLLVM_ENABLE_CURL=ON
    -DLLVM_ENABLE_FFI=ON
    -DLLVM_ENABLE_RTTI=ON
    -DLLVM_ENABLE_SPHINX=ON
    -DLLVM_HOST_TRIPLE=$CHOST
    -DLLVM_INCLUDE_BENCHMARKS=OFF
    -DLLVM_INSTALL_GTEST=ON
    -DLLVM_INSTALL_UTILS=ON
    -DLLVM_LINK_LLVM_DYLIB=ON
    -DLLVM_USE_PERF=ON
    -DSPHINX_WARNINGS_AS_ERRORS=OFF
    -DPACKAGE_BUGREPORT=https://gitlab.archlinux.org/archlinux/packaging/packages/llvm/-/issues
  )

  export AR=llvm-ar
  export CC=clang
  export CXX=clang++
  export NM=llvm-nm
  export RANLIB=llvm-ranlib
  # Export Original CFLAGS
  export ORIG_CFLAGS="${CFLAGS}"
  export ORIG_CXXFLAGS="${CXXFLAGS}"

  export CFLAGS+=" -fprofile-generate"
  export CXXFLAGS+=" -fprofile-generate"

  cmake .. "${cmake_args[@]}"
  local distribution_components=$(_get_distribution_components | paste -sd\;)
  test -n "$distribution_components"
  cmake_args+=(-DLLVM_DISTRIBUTION_COMPONENTS="$distribution_components")

  # Build LLVM with -fprofile generate
  cmake .. -DCMAKE_BUILD_TYPE=Release -DLLVM_BUILD_INSTRUMENTED=IR -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++ -DLLVM_USE_LINKER=lld -DLLVM_VP_COUNTERS_PER_SITE=6 "${cmake_args[@]}"
  ninja

  # Run LLVM lit tests to generate profile to be used for PGO
  ./bin/llvm-lit -v test || true

  # Merge the generated profile
  llvm-profdata merge -o llvm.profdata "${srcdir}/llvm-project-$pkgver.src/llvm/build/profiles"/*.profraw

  # Use Original CFLAGS again and enable ThinLTO + use the profile
  export PGO_PROFILE="${srcdir}/llvm-project-$pkgver.src/llvm/build/llvm.profdata"
  export CFLAGS="${ORIG_CFLAGS} -fprofile-use=$PGO_PROFILE"
  export CXXFLAGS="${ORIG_CXXFLAGS} -fprofile-use=$PGO_PROFILE"
  export LDFLAGS="$LDFLAGS -flto=thin"

  cd ..
  mkdir build-pgo-use
  cd build-pgo-use
  # Enable ThinLTO
  cmake .. -DCMAKE_BUILD_TYPE=Release -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++ -DLLVM_USE_LINKER=lld -DLLVM_ENABLE_LTO=Thin -DLLVM_PROFDATA_FILE=$PGO_PROFILE "${cmake_args[@]}"
  ninja

  # Include lit for running lit-based tests in other projects
  pushd ../utils/lit
  python -m build --wheel --no-isolation
  popd
}

check() {
  cd llvm-project-$pkgver.src/llvm/build-pgo-use
  LD_LIBRARY_PATH=$PWD/lib ninja check
}

package_llvm() {
  pkgdesc="Compiler infrastructure"
  depends=('llvm-libs' 'curl' 'perl' 'libstdc++' 'glibc' 'libgcc')

  cd llvm-project-$pkgver.src/llvm/build-pgo-use

  DESTDIR="$pkgdir" ninja install-distribution

  # Include lit for running lit-based tests in other projects
  pushd ../utils/lit
  python -m installer --destdir="$pkgdir" dist/*.whl
  popd

  # The runtime libraries go into llvm-libs
  mv -f "$pkgdir"/usr/lib/lib{LLVM,LTO,Remarks}*.so* "$srcdir"
  mv -f "$pkgdir"/usr/lib/LLVMgold.so "$srcdir"

  # Remove documentation sources
  rm -r "$pkgdir"/usr/share/doc/llvm/html/{_sources,.buildinfo}

  install -Dm644 ../LICENSE.TXT "$pkgdir/usr/share/licenses/$pkgname/LICENSE"
}

package_llvm-libs() {
  pkgdesc="LLVM runtime libraries"
  depends=('libgcc' 'glibc' 'libstdc++' 'zlib' 'zstd' 'libffi' 'libedit' 'libxml2')
  provides=('libLLVM.so' 'libLTO.so' 'libRemarks.so')

  install -d "$pkgdir/usr/lib"
  cp -P \
    "$srcdir"/lib{LLVM,LTO,Remarks}*.so* \
    "$srcdir"/LLVMgold.so \
    "$pkgdir/usr/lib/"

  # Symlink LLVMgold.so from /usr/lib/bfd-plugins
  # https://bugs.archlinux.org/task/28479
  install -d "$pkgdir/usr/lib/bfd-plugins"
  ln -s ../LLVMgold.so "$pkgdir/usr/lib/bfd-plugins/LLVMgold.so"

  install -Dm644 "$srcdir/llvm-project-$pkgver.src/llvm/LICENSE.TXT" \
    "$pkgdir/usr/share/licenses/$pkgname/LICENSE"
}

# vim:set ts=2 sw=2 et:

