sys-devel/llvm/llvm-16.0_pre484197_p20230405.ebuild - third_party/overlays/chromiumos-overlay - Git at Google

 # Copyright 1999-2015 Gentoo Foundation
 # Distributed under the terms of the GNU General Public License v2
 # $Id$

 EAPI=7

 PYTHON_COMPAT=( python3_{6..9} )

 inherit cros-constants cmake flag-o-matic git-r3 multilib-minimal  \
 	python-single-r1 pax-utils toolchain-funcs

 LLVM_HASH="2916b99182752b1aece8cc4479d8d6a20b5e02da" # r484197
 LLVM_NEXT_HASH="98f5a340975bc00197c57e39eb4ca26e2da0e8a2" # r496208

 DESCRIPTION="Low Level Virtual Machine"
 HOMEPAGE="http://llvm.org/"
 SRC_URI="
 	!llvm-tot? (
 		!llvm-next? ( llvm_pgo_use? ( gs://chromeos-localmirror/distfiles/llvm-profdata-${LLVM_HASH}.tar.xz ) )
 		llvm-next? ( llvm-next_pgo_use? ( gs://chromeos-localmirror/distfiles/llvm-profdata-${LLVM_NEXT_HASH}.tar.xz ) )
 	)
 "
 EGIT_REPO_URI="${CROS_GIT_HOST_URL}/external/github.com/llvm/llvm-project
 	${CROS_GIT_HOST_URL}/external/github.com/llvm/llvm-project"
 EGIT_BRANCH=main

 LICENSE="UoI-NCSA"
 SLOT="8"
 KEYWORDS="-* amd64"
 # FIXME: llvm-tot is somewhat misleading: at the moment, it's essentially
 # llvm-next with a few extra checks enabled
 IUSE="debug +default-compiler-rt +default-libcxx doc +libedit +libffi +llvm-crt
 	llvm-next llvm_pgo_generate +llvm_pgo_use llvm-next_pgo_use llvm-tot
 	multitarget ncurses ocaml test +thinlto xml video_cards_radeon continue-on-patch-failure"

 COMMON_DEPEND="
 	sys-libs/zlib:0=[${MULTILIB_USEDEP}]
 	libedit? ( dev-libs/libedit:0=[${MULTILIB_USEDEP}] )
 	libffi? ( >=dev-libs/libffi-3.0.13-r1:0=[${MULTILIB_USEDEP}] )
 	ncurses? ( >=sys-libs/ncurses-5.9-r3:0=[${MULTILIB_USEDEP}] )
 	ocaml? (
 		>=dev-lang/ocaml-4.00.0:0=
 		dev-ml/findlib
 		dev-ml/ocaml-ctypes )"
 # configparser-3.2 breaks the build (3.3 or none at all are fine)
 DEPEND="${COMMON_DEPEND}
 	sys-devel/binutils
 	ocaml? ( test? ( dev-ml/ounit ) )"
 RDEPEND="${COMMON_DEPEND}
 	abi_x86_32? ( !<=app-emulation/emul-linux-x86-baselibs-20130224-r2
 		!app-emulation/emul-linux-x86-baselibs[-abi_x86_32(-)] )
 	!<=sys-devel/llvm-8.0_pre
 	!sys-devel/lld
 	!sys-devel/clang"
 BDEPEND="
 	dev-lang/perl
 	libffi? ( virtual/pkgconfig )
 	sys-devel/gnuconfig
 	$(python_gen_cond_dep '
 		dev-python/sphinx[${PYTHON_USEDEP}]
 		doc? ( dev-python/recommonmark[${PYTHON_USEDEP}] )
 	')
 "

 # pypy gives me around 1700 unresolved tests due to open file limit
 # being exceeded. probably GC does not close them fast enough.
 REQUIRED_USE="
 	llvm_pgo_generate? ( !llvm_pgo_use )"

 check_lld_works() {
 	echo 'int main() {return 0;}' > "${T}"/lld.cxx || die
 	echo "Trying to link program with lld"
 	$(tc-getCXX) -fuse-ld=lld -std=c++11 -o /dev/null "${T}"/lld.cxx
 }

 check_pgo_works() {
 	echo 'int main() {return 0;}' > "${T}"/pgo.cxx || die
 	echo "Trying to link program with pgo"
 	$(tc-getCXX) -std=c++11 -o /dev/null "${T}"/pgo.cxx -fprofile-instr-use="${WORKDIR}"/llvm.profdata
 }

 apply_pgo_profile() {
 	! use llvm-tot && ( \
 		( use llvm-next && use llvm-next_pgo_use ) ||
 		( ! use llvm-next && use llvm_pgo_use ) )
 }

 src_unpack() {
 	export CMAKE_USE_DIR="${S}/llvm"

 	if use llvm-next || use llvm-tot; then
 		EGIT_COMMIT="${LLVM_NEXT_HASH}"
 	else
 		EGIT_COMMIT="${LLVM_HASH}"
 	fi

 	git-r3_src_unpack

 	if apply_pgo_profile; then
 		cd "${WORKDIR}" || die
 		local profile_hash
 		if use llvm-next; then
 			profile_hash="${LLVM_NEXT_HASH}"
 		else
 			profile_hash="${LLVM_HASH}"
 		fi
 		unpack "llvm-profdata-${profile_hash}.tar.xz"
 	fi
 }

 get_most_recent_revision() {
 	local subdir="${S}/llvm"

 	# Tries to get the revision ID of the most recent commit
 	"${FILESDIR}"/patch_manager/git_llvm_rev.py --llvm_dir "${subdir}" --sha "$(git -C "${subdir}" rev-parse HEAD)" | cut -d 'r' -f 2
 }

 src_prepare() {
 	# Make ocaml warnings non-fatal, bug #537308
 	sed -e "/RUN/s/-warn-error A//" -i llvm/test/Bindings/OCaml/*ml  || die

 	python_setup

 	local failure_mode
 	failure_mode="$(usex continue-on-patch-failure continue fail)"
 	"${FILESDIR}"/patch_manager/patch_manager.py \
 		--svn_version "$(get_most_recent_revision)" \
 		--patch_metadata_file "${FILESDIR}"/PATCHES.json \
 		--failure_mode "${failure_mode}" \
 		--src_path "${S}" || die

 	cmake_src_prepare

 	# Native libdir is used to hold LLVMgold.so
 	# shellcheck disable=SC2034
 	NATIVE_LIBDIR=$(get_libdir)
 }

 enable_asserts() {
 	# keep asserts enabled for llvm-tot
 	if use llvm-tot; then
 		echo yes
 	else
 		usex debug
 	fi
 }

 multilib_src_configure() {
 	export CMAKE_BUILD_TYPE="RelWithDebInfo"

 	append-flags -Wno-poison-system-directories

 	local targets
 	if use multitarget; then
 	# for LLVM breakages specific to BPF (only)
 	# contact cros-enterprise-security@google.com
 	# for everything else contact OWNERs
 		targets='host;X86;ARM;AArch64;NVPTX;BPF'
 	else
 		targets='host;CppBackend'
 		use video_cards_radeon && targets+=';AMDGPU'
 	fi

 	local ffi_cflags ffi_ldflags
 	if use libffi; then
 		ffi_cflags=$($(tc-getPKG_CONFIG) --cflags-only-I libffi)
 		ffi_ldflags=$($(tc-getPKG_CONFIG) --libs-only-L libffi)
 	fi

 	local libdir=$(get_libdir)
 	local mycmakeargs=(
 		"${mycmakeargs[@]}"
 		"-DLLVM_ENABLE_PROJECTS=llvm;clang;lld;lldb;compiler-rt;clang-tools-extra"
 		"-DLLVM_LIBDIR_SUFFIX=${libdir#lib}"

 		"-DLLVM_BUILD_LLVM_DYLIB=ON"
 		# Link LLVM statically
 		"-DLLVM_LINK_LLVM_DYLIB=OFF"
 		"-DBUILD_SHARED_LIBS=OFF"

 		"-DLLVM_ENABLE_TIMESTAMPS=OFF"
 		"-DLLVM_TARGETS_TO_BUILD=${targets}"
 		"-DLLVM_BUILD_TESTS=$(usex test)"

 		"-DLLVM_ENABLE_FFI=$(usex libffi)"
 		"-DLLVM_ENABLE_TERMINFO=$(usex ncurses)"
 		"-DLLVM_ENABLE_ASSERTIONS=$(enable_asserts)"
 		"-DLLVM_ENABLE_EH=ON"
 		"-DLLVM_ENABLE_RTTI=ON"

 		"-DWITH_POLLY=OFF" # TODO

 		"-DLLVM_HOST_TRIPLE=${CHOST}"

 		"-DFFI_INCLUDE_DIR=${ffi_cflags#-I}"
 		"-DFFI_LIBRARY_DIR=${ffi_ldflags#-L}"
 		"-DLLVM_BINUTILS_INCDIR=${SYSROOT}/usr/include"

 		"-DHAVE_HISTEDIT_H=$(usex libedit)"
 		"-DENABLE_LINKER_BUILD_ID=ON"
 		"-DCLANG_VENDOR=Chromium OS ${PVR}"
 		# override default stdlib and rtlib
 		"-DCLANG_DEFAULT_CXX_STDLIB=$(usex default-libcxx libc++ "")"
 		"-DCLANG_DEFAULT_RTLIB=$(usex default-compiler-rt compiler-rt "")"

 		# crbug/855759
 		"-DCOMPILER_RT_BUILD_CRT=$(usex llvm-crt)"

 		"-DCMAKE_POSITION_INDEPENDENT_CODE=ON"
 		"-DCLANG_DEFAULT_UNWINDLIB=libgcc"
 		"-DCLANG_DEFAULT_PIE_ON_LINUX=ON"

 		# workaround for crbug/1198796
 		"-DCLANG_TOOLING_BUILD_AST_INTROSPECTION=OFF"

 		# By default do not enable PGO for compiler-rt
 		"-DCOMPILER_RT_ENABLE_PGO=OFF"

 		# compiler-rt needs libc++ sources to be specified to build
 		# an internal copy for libfuzzer, can be removed if libc++
 		# is built inside llvm ebuild.
 		"-DCOMPILER_RT_LIBCXXABI_PATH=${S}/libcxxabi"
 		"-DCOMPILER_RT_LIBCXX_PATH=${S}/libcxx"
 		"-DCOMPILER_RT_BUILTINS_HIDE_SYMBOLS=OFF"

 		# b/200831212: Disable per runtime install dirs.
 		"-DLLVM_ENABLE_PER_TARGET_RUNTIME_DIR=OFF"

 		# b/202073091: Disable Lua.
 		"-DLLDB_ENABLE_LUA=OFF"

 		# b/204220308: Disable ORC since we are not using it.
 		"-DCOMPILER_RT_BUILD_ORC=OFF"

 		# b/241569725: Explicitly set Python version so that it
 		# chooses the version we're currently supporting
 		"-DPython3_EXECUTABLE=${PYTHON}"
 	)

 	if check_lld_works; then
 		mycmakeargs+=(
 			# We use lld to link llvm, because:
 			# 1) Gold has issue with no index for archive,
 			# 2) Gold doesn't support instrumented compiler-rt well.
 			"-DLLVM_USE_LINKER=lld"
 		)
 		# The standalone toolchain may be run at places not supporting
 		# smallPIE, disabling it for lld.
 		# Pass -fuse-ld=lld to make cmake happy.
 		append-ldflags "-fuse-ld=lld -Wl,--pack-dyn-relocs=none"
 		# Disable warning about profile not matching.
 		append-flags "-Wno-backend-plugin"

 		if use thinlto; then
 			mycmakeargs+=(
 				"-DLLVM_ENABLE_LTO=thin"
 				# b/228090090: LLVM defaults to 2 parallel link
 				# jobs with ThinLTO enabled. Bumping this to 4
 				# speeds `emerge llvm` up on dev machines by
 				# 1.25x, and saves >10mins per LLVM build on the
 				# SDK builder.
 				"-DLLVM_PARALLEL_LINK_JOBS=4"
 			)
 			# b/227370760: Instr limits above 30 don't seem to help
 			# our performance (and might hurt in some cases). They
 			# also make builds take meaningfully longer, and add
 			# tens of MB to our SDK size. We tune this back in other
 			# large ThinLTO users (e.g., Chrome), so do it here,
 			# too.
 			append-ldflags "-Wl,-mllvm,-import-instr-limit=30"
 		fi

 		if apply_pgo_profile; then
 			if check_pgo_works; then
 				mycmakeargs+=(
 					"-DLLVM_PROFDATA_FILE=${WORKDIR}/llvm.profdata"
 				)
 			else
 				# PGO profile did not work which is only acceptable
 				# for the cases where llvm hash != profile hash.
 				# Error out in other cases.
 				$(tc-getCC) --version | grep -q "\b${EGIT_COMMIT}" && die \
 					"Could not build with PGO profile at sha ${EGIT_COMMIT}".
 				echo "Could not build with pgo profile, skipping pgo."
 			fi
 		fi

 		if use llvm_pgo_generate; then
 			mycmakeargs+=(
 				"-DLLVM_BUILD_INSTRUMENTED=IR"
 			)
 		fi
 	fi

 	if ! multilib_is_native_abi || ! use ocaml; then
 		mycmakeargs+=(
 			"-DOCAMLFIND=NO"
 		)
 	fi
 #	Note: go bindings have no CMake rules at the moment
 #	but let's kill the check in case they are introduced
 #	if ! multilib_is_native_abi || ! use go; then
 		mycmakeargs+=(
 			"-DGO_EXECUTABLE=GO_EXECUTABLE-NOTFOUND"
 		)
 #	fi

 	if [[ -z "${CCACHE_DISABLE:-}" ]]; then
 		# If ccache is enabled, use it as a compiler launcher. Chances
 		# are that folks are iterating on LLVM, and ccache speeds that
 		# up substantially.
 		mycmakeargs+=(
 			"-DCMAKE_C_COMPILER_LAUNCHER=ccache"
 			"-DCMAKE_CXX_COMPILER_LAUNCHER=ccache"
 		)
 	fi

 	if multilib_is_native_abi; then
 		mycmakeargs+=(
 			"-DLLVM_BUILD_DOCS=$(usex doc)"
 			"-DLLVM_ENABLE_SPHINX=$(usex doc)"
 			"-DLLVM_ENABLE_DOXYGEN=OFF"
 			"-DLLVM_INSTALL_HTML=${EPREFIX}/usr/share/doc/${PF}/html"
 			"-DSPHINX_WARNINGS_AS_ERRORS=OFF"
 			"-DLLVM_INSTALL_UTILS=ON"
 		)
 	fi

 	if ! use debug; then
 		append-cppflags -DNDEBUG
 	fi

 	cmake_src_configure
 }

 multilib_src_compile() {
 	# ...If folks are iterating on LLVM with `emerge`, every successful
 	# `emerge` invocation will replace their old compiler. Since doing so
 	# updates mtimes, we should be focusing on the _content_ of the
 	# compiler, rather than the mtime.
 	#
 	# Note that this is in `src_compile`, since it won't apply if we do it
 	# in `src_configure`.
 	export CCACHE_COMPILERCHECK=content
 	cmake_src_compile

 	pax-mark m "${BUILD_DIR}"/bin/llvm-rtdyld
 	pax-mark m "${BUILD_DIR}"/bin/lli
 	pax-mark m "${BUILD_DIR}"/bin/lli-child-target

 	if use test; then
 		pax-mark m "${BUILD_DIR}"/unittests/ExecutionEngine/Orc/OrcJITTests
 		pax-mark m "${BUILD_DIR}"/unittests/ExecutionEngine/MCJIT/MCJITTests
 		pax-mark m "${BUILD_DIR}"/unittests/Support/SupportTests
 	fi
 }

 multilib_src_test() {
 	# respect TMPDIR!
 	local -x LIT_PRESERVES_TMP=1
 	cmake_src_test
 }

 src_install() {
 	local MULTILIB_CHOST_TOOLS=(
 		/usr/bin/llvm-config
 	)

 	local MULTILIB_WRAPPED_HEADERS=(
 		/usr/include/llvm/Config/config.h
 		/usr/include/llvm/Config/llvm-config.h
 	)

 	multilib-minimal_src_install
 }

 # This computes the toolchain SHA that gets baked into our compiler_wrapper
 # binaries. This SHA is potentially nice for uniquely identifying a toolchain,
 # but the most critical purpose that it serves is making the SHA for our
 # compiler_wrapper change with the toolchain that it was installed with. If any
 # of these binaries get modified and we fail to update compiler_wrapper, tools
 # like ccache, ninja, etc might not expect the updates without extra work (thus,
 # cached object files might not be considered stale across compiler updates).
 #
 # Rather than playing whack-a-mole with ways to inform each build system that
 # our compiler has changed (despite its hash remaining identical), we simply
 # modify its hash when any of the binaries it calls may change.
 compute_toolchain_sha() {
 	local toolchain_sha_binaries=(
 		"bin/clang"
 		"bin/clang-tidy"
 		"bin/ld.lld"
 	)

 	# Compute the SHA sums for each of these in parallel, then hash the
 	# result. This hash represents all of the (non-header, non-library)
 	# dependencies that Clang has.
 	#
 	# This is expected to be called in a subshell, so don't try to restore
 	# pipefail.
 	set -o pipefail
 	echo "${toolchain_sha_binaries[*]}" |
 		xargs -L1 -P8 sha256sum |
 		sort -k2 |
 		sha256sum - |
 		awk '{print $1}'
 }

 multilib_src_install() {
 	cmake_src_install

 	local use_llvm_next=false
 	if use llvm-next || use llvm-tot
 	then
 		use_llvm_next=true
 	fi
 	local wrapper_script=clang_host_wrapper

 	local toolchain_sha
 	echo "Current directory is $(pwd)"
 	toolchain_sha="$(compute_toolchain_sha)" || die
 	einfo "Computed toolchain SHA = ${toolchain_sha}"

 	local common_wrapper_flags=(
 		"--version_suffix=_toolchain_sha_${toolchain_sha}"
 	)

 	GO111MODULE=off "${FILESDIR}/compiler_wrapper/build.py" --config=cros.host --use_ccache=false \
 		--use_llvm_next="${use_llvm_next}" \
 		--output_file="${D}/usr/bin/${wrapper_script}" \
 		"${common_wrapper_flags[@]}" || die

 	newbin "${D}/usr/bin/clang-tidy" "clang-tidy"
 	dobin "${FILESDIR}/bisect_driver.py"
 	dobin "${FILESDIR}/clang_cc_wrapper"
 	exeinto "/usr/bin"
 	dosym "${wrapper_script}" "/usr/bin/${CHOST}-clang"
 	dosym "${wrapper_script}" "/usr/bin/${CHOST}-clang++"
 	newexe "${FILESDIR}/ldwrapper_lld.host" "${CHOST}-ld.lld"

 	# llvm-strip is a symlink to llvm-objcopy and distinguished by a argv[0] check.
 	# When creating standalone toolchain, argv[0] information is lost and causes
 	# llvm-strip invocations to be treated as llvm-objcopy breaking builds
 	# (crbug.com/1151787). Handle this by making llvm-strip a full binary.
 	if [[ -L "${D}/usr/bin/llvm-strip" ]]; then
 		rm "${D}/usr/bin/llvm-strip" || die
 		newbin "${D}/usr/bin/llvm-objcopy" "llvm-strip"
 	fi

 	# Build and install cross-compiler wrappers for supported ABIs.
 	# ccache wrapper is used in chroot and non-ccache wrapper is used
 	# in standalone SDK.
 	local ccache_suffixes=(noccache ccache)
 	local ccache_option_values=(false true)
 	for ccache_index in {0,1}; do
 		local ccache_suffix="${ccache_suffixes[${ccache_index}]}"
 		local ccache_option="${ccache_option_values[${ccache_index}]}"
 		# Build hardened wrapper written in golang.
 		GO111MODULE=off "${FILESDIR}/compiler_wrapper/build.py" --config="cros.hardened" \
 			--use_ccache="${ccache_option}" \
 			--use_llvm_next="${use_llvm_next}" \
 			--output_file="${D}/usr/bin/sysroot_wrapper.hardened.${ccache_suffix}" \
 			"${common_wrapper_flags[@]}" || die

 		# Build non-hardened wrapper written in golang.
 		GO111MODULE=off "${FILESDIR}/compiler_wrapper/build.py" --config="cros.nonhardened" \
 			--use_ccache="${ccache_option}" \
 			--use_llvm_next="${use_llvm_next}" \
 			--output_file="${D}/usr/bin/sysroot_wrapper.${ccache_suffix}" \
 			"${common_wrapper_flags[@]}" || die
 	done

 	local cros_hardened_targets=(
 		"aarch64-cros-linux-gnu"
 		"armv7a-cros-linux-gnueabihf"
 		"i686-cros-linux-gnu"
 		"x86_64-cros-linux-gnu"
 	)
 	local cros_nonhardened_targets=(
 		"arm-none-eabi"
 		"armv7m-cros-eabi"
 	)

 	local target
 	for target in "${cros_hardened_targets[@]}"; do
 		dosym "sysroot_wrapper.hardened.ccache" "/usr/bin/${target}-clang"
 		dosym "sysroot_wrapper.hardened.ccache" "/usr/bin/${target}-clang++"
 	done
 	for target in "${cros_nonhardened_targets[@]}"; do
 		dosym "sysroot_wrapper.ccache" "/usr/bin/${target}-clang"
 		dosym "sysroot_wrapper.ccache" "/usr/bin/${target}-clang++"
 	done

 	# Install a symlink bpf-clang which point to clang.
 	# Running through symlink will make clang default to bpf target.
 	dosym "clang" "/usr/bin/bpf-clang"

 	# Remove this file, if it exists, to avoid installation file collision,
 	# as this file is also generated/installed by the dev-python/six package.
 	find "${D}"/usr -name 'six.py' -delete
 }

 multilib_src_install_all() {
 	insinto /usr/share/vim/vimfiles
 	doins -r llvm/utils/vim/*/.
 	# some users may find it useful
 	dodoc llvm/utils/vim/vimrc
 	dobin "${S}/compiler-rt/lib/asan/scripts/asan_symbolize.py"
 }

 pkg_postinst() {
 	if has_version ">=dev-util/ccache-3.1.9-r2" ; then
 		#add ccache links as clang might get installed after ccache
 		"${EROOT}"/usr/bin/ccache-config --install-links
 	fi
 }

 pkg_postrm() {
 	if has_version ">=dev-util/ccache-3.1.9-r2" && [[ -z ${REPLACED_BY_VERSION} ]]; then
 		# --remove-links would remove all links, --install-links updates them
 		"${EROOT}"/usr/bin/ccache-config --install-links
 	fi
 }
	# Copyright 1999-2015 Gentoo Foundation
	# Distributed under the terms of the GNU General Public License v2
	# $Id$

	EAPI=7

	PYTHON_COMPAT=( python3_{6..9} )

	inherit cros-constants cmake flag-o-matic git-r3 multilib-minimal \
	python-single-r1 pax-utils toolchain-funcs

	LLVM_HASH="2916b99182752b1aece8cc4479d8d6a20b5e02da" # r484197
	LLVM_NEXT_HASH="98f5a340975bc00197c57e39eb4ca26e2da0e8a2" # r496208

	DESCRIPTION="Low Level Virtual Machine"
	HOMEPAGE="http://llvm.org/"
	SRC_URI="
	!llvm-tot? (
	!llvm-next? ( llvm_pgo_use? ( gs://chromeos-localmirror/distfiles/llvm-profdata-${LLVM_HASH}.tar.xz ) )
	llvm-next? ( llvm-next_pgo_use? ( gs://chromeos-localmirror/distfiles/llvm-profdata-${LLVM_NEXT_HASH}.tar.xz ) )
	)
	"
	EGIT_REPO_URI="${CROS_GIT_HOST_URL}/external/github.com/llvm/llvm-project
	${CROS_GIT_HOST_URL}/external/github.com/llvm/llvm-project"
	EGIT_BRANCH=main

	LICENSE="UoI-NCSA"
	SLOT="8"
	KEYWORDS="-* amd64"
	# FIXME: llvm-tot is somewhat misleading: at the moment, it's essentially
	# llvm-next with a few extra checks enabled
	IUSE="debug +default-compiler-rt +default-libcxx doc +libedit +libffi +llvm-crt
	llvm-next llvm_pgo_generate +llvm_pgo_use llvm-next_pgo_use llvm-tot
	multitarget ncurses ocaml test +thinlto xml video_cards_radeon continue-on-patch-failure"

	COMMON_DEPEND="
	sys-libs/zlib:0=[${MULTILIB_USEDEP}]
	libedit? ( dev-libs/libedit:0=[${MULTILIB_USEDEP}] )
	libffi? ( >=dev-libs/libffi-3.0.13-r1:0=[${MULTILIB_USEDEP}] )
	ncurses? ( >=sys-libs/ncurses-5.9-r3:0=[${MULTILIB_USEDEP}] )
	ocaml? (
	>=dev-lang/ocaml-4.00.0:0=
	dev-ml/findlib
	dev-ml/ocaml-ctypes )"
	# configparser-3.2 breaks the build (3.3 or none at all are fine)
	DEPEND="${COMMON_DEPEND}
	sys-devel/binutils
	ocaml? ( test? ( dev-ml/ounit ) )"
	RDEPEND="${COMMON_DEPEND}
	abi_x86_32? ( !<=app-emulation/emul-linux-x86-baselibs-20130224-r2
	!app-emulation/emul-linux-x86-baselibs[-abi_x86_32(-)] )
	!<=sys-devel/llvm-8.0_pre
	!sys-devel/lld
	!sys-devel/clang"
	BDEPEND="
	dev-lang/perl
	libffi? ( virtual/pkgconfig )
	sys-devel/gnuconfig
	$(python_gen_cond_dep '
	dev-python/sphinx[${PYTHON_USEDEP}]
	doc? ( dev-python/recommonmark[${PYTHON_USEDEP}] )
	')
	"

	# pypy gives me around 1700 unresolved tests due to open file limit
	# being exceeded. probably GC does not close them fast enough.
	REQUIRED_USE="
	llvm_pgo_generate? ( !llvm_pgo_use )"

	check_lld_works() {
	echo 'int main() {return 0;}' > "${T}"/lld.cxx \|\| die
	echo "Trying to link program with lld"
	$(tc-getCXX) -fuse-ld=lld -std=c++11 -o /dev/null "${T}"/lld.cxx
	}

	check_pgo_works() {
	echo 'int main() {return 0;}' > "${T}"/pgo.cxx \|\| die
	echo "Trying to link program with pgo"
	$(tc-getCXX) -std=c++11 -o /dev/null "${T}"/pgo.cxx -fprofile-instr-use="${WORKDIR}"/llvm.profdata
	}

	apply_pgo_profile() {
	! use llvm-tot && ( \
	( use llvm-next && use llvm-next_pgo_use ) \|\|
	( ! use llvm-next && use llvm_pgo_use ) )
	}

	src_unpack() {
	export CMAKE_USE_DIR="${S}/llvm"

	if use llvm-next \|\| use llvm-tot; then
	EGIT_COMMIT="${LLVM_NEXT_HASH}"
	else
	EGIT_COMMIT="${LLVM_HASH}"
	fi

	git-r3_src_unpack

	if apply_pgo_profile; then
	cd "${WORKDIR}" \|\| die
	local profile_hash
	if use llvm-next; then
	profile_hash="${LLVM_NEXT_HASH}"
	else
	profile_hash="${LLVM_HASH}"
	fi
	unpack "llvm-profdata-${profile_hash}.tar.xz"
	fi
	}

	get_most_recent_revision() {
	local subdir="${S}/llvm"

	# Tries to get the revision ID of the most recent commit
	"${FILESDIR}"/patch_manager/git_llvm_rev.py --llvm_dir "${subdir}" --sha "$(git -C "${subdir}" rev-parse HEAD)" \| cut -d 'r' -f 2
	}

	src_prepare() {
	# Make ocaml warnings non-fatal, bug #537308
	sed -e "/RUN/s/-warn-error A//" -i llvm/test/Bindings/OCaml/*ml \|\| die

	python_setup

	local failure_mode
	failure_mode="$(usex continue-on-patch-failure continue fail)"
	"${FILESDIR}"/patch_manager/patch_manager.py \
	--svn_version "$(get_most_recent_revision)" \
	--patch_metadata_file "${FILESDIR}"/PATCHES.json \
	--failure_mode "${failure_mode}" \
	--src_path "${S}" \|\| die

	cmake_src_prepare

	# Native libdir is used to hold LLVMgold.so
	# shellcheck disable=SC2034
	NATIVE_LIBDIR=$(get_libdir)
	}

	enable_asserts() {
	# keep asserts enabled for llvm-tot
	if use llvm-tot; then
	echo yes
	else
	usex debug
	fi
	}

	multilib_src_configure() {
	export CMAKE_BUILD_TYPE="RelWithDebInfo"

	append-flags -Wno-poison-system-directories

	local targets
	if use multitarget; then
	# for LLVM breakages specific to BPF (only)
	# contact cros-enterprise-security@google.com
	# for everything else contact OWNERs
	targets='host;X86;ARM;AArch64;NVPTX;BPF'
	else
	targets='host;CppBackend'
	use video_cards_radeon && targets+=';AMDGPU'
	fi

	local ffi_cflags ffi_ldflags
	if use libffi; then
	ffi_cflags=$($(tc-getPKG_CONFIG) --cflags-only-I libffi)
	ffi_ldflags=$($(tc-getPKG_CONFIG) --libs-only-L libffi)
	fi

	local libdir=$(get_libdir)
	local mycmakeargs=(
	"${mycmakeargs[@]}"
	"-DLLVM_ENABLE_PROJECTS=llvm;clang;lld;lldb;compiler-rt;clang-tools-extra"
	"-DLLVM_LIBDIR_SUFFIX=${libdir#lib}"

	"-DLLVM_BUILD_LLVM_DYLIB=ON"
	# Link LLVM statically
	"-DLLVM_LINK_LLVM_DYLIB=OFF"
	"-DBUILD_SHARED_LIBS=OFF"

	"-DLLVM_ENABLE_TIMESTAMPS=OFF"
	"-DLLVM_TARGETS_TO_BUILD=${targets}"
	"-DLLVM_BUILD_TESTS=$(usex test)"

	"-DLLVM_ENABLE_FFI=$(usex libffi)"
	"-DLLVM_ENABLE_TERMINFO=$(usex ncurses)"
	"-DLLVM_ENABLE_ASSERTIONS=$(enable_asserts)"
	"-DLLVM_ENABLE_EH=ON"
	"-DLLVM_ENABLE_RTTI=ON"

	"-DWITH_POLLY=OFF" # TODO

	"-DLLVM_HOST_TRIPLE=${CHOST}"

	"-DFFI_INCLUDE_DIR=${ffi_cflags#-I}"
	"-DFFI_LIBRARY_DIR=${ffi_ldflags#-L}"
	"-DLLVM_BINUTILS_INCDIR=${SYSROOT}/usr/include"

	"-DHAVE_HISTEDIT_H=$(usex libedit)"
	"-DENABLE_LINKER_BUILD_ID=ON"
	"-DCLANG_VENDOR=Chromium OS ${PVR}"
	# override default stdlib and rtlib
	"-DCLANG_DEFAULT_CXX_STDLIB=$(usex default-libcxx libc++ "")"
	"-DCLANG_DEFAULT_RTLIB=$(usex default-compiler-rt compiler-rt "")"

	# crbug/855759
	"-DCOMPILER_RT_BUILD_CRT=$(usex llvm-crt)"

	"-DCMAKE_POSITION_INDEPENDENT_CODE=ON"
	"-DCLANG_DEFAULT_UNWINDLIB=libgcc"
	"-DCLANG_DEFAULT_PIE_ON_LINUX=ON"

	# workaround for crbug/1198796
	"-DCLANG_TOOLING_BUILD_AST_INTROSPECTION=OFF"

	# By default do not enable PGO for compiler-rt
	"-DCOMPILER_RT_ENABLE_PGO=OFF"

	# compiler-rt needs libc++ sources to be specified to build
	# an internal copy for libfuzzer, can be removed if libc++
	# is built inside llvm ebuild.
	"-DCOMPILER_RT_LIBCXXABI_PATH=${S}/libcxxabi"
	"-DCOMPILER_RT_LIBCXX_PATH=${S}/libcxx"
	"-DCOMPILER_RT_BUILTINS_HIDE_SYMBOLS=OFF"

	# b/200831212: Disable per runtime install dirs.
	"-DLLVM_ENABLE_PER_TARGET_RUNTIME_DIR=OFF"

	# b/202073091: Disable Lua.
	"-DLLDB_ENABLE_LUA=OFF"

	# b/204220308: Disable ORC since we are not using it.
	"-DCOMPILER_RT_BUILD_ORC=OFF"

	# b/241569725: Explicitly set Python version so that it
	# chooses the version we're currently supporting
	"-DPython3_EXECUTABLE=${PYTHON}"
	)

	if check_lld_works; then
	mycmakeargs+=(
	# We use lld to link llvm, because:
	# 1) Gold has issue with no index for archive,
	# 2) Gold doesn't support instrumented compiler-rt well.
	"-DLLVM_USE_LINKER=lld"
	)
	# The standalone toolchain may be run at places not supporting
	# smallPIE, disabling it for lld.
	# Pass -fuse-ld=lld to make cmake happy.
	append-ldflags "-fuse-ld=lld -Wl,--pack-dyn-relocs=none"
	# Disable warning about profile not matching.
	append-flags "-Wno-backend-plugin"

	if use thinlto; then
	mycmakeargs+=(
	"-DLLVM_ENABLE_LTO=thin"
	# b/228090090: LLVM defaults to 2 parallel link
	# jobs with ThinLTO enabled. Bumping this to 4
	# speeds `emerge llvm` up on dev machines by
	# 1.25x, and saves >10mins per LLVM build on the
	# SDK builder.
	"-DLLVM_PARALLEL_LINK_JOBS=4"
	)
	# b/227370760: Instr limits above 30 don't seem to help
	# our performance (and might hurt in some cases). They
	# also make builds take meaningfully longer, and add
	# tens of MB to our SDK size. We tune this back in other
	# large ThinLTO users (e.g., Chrome), so do it here,
	# too.
	append-ldflags "-Wl,-mllvm,-import-instr-limit=30"
	fi

	if apply_pgo_profile; then
	if check_pgo_works; then
	mycmakeargs+=(
	"-DLLVM_PROFDATA_FILE=${WORKDIR}/llvm.profdata"
	)
	else
	# PGO profile did not work which is only acceptable
	# for the cases where llvm hash != profile hash.
	# Error out in other cases.
	$(tc-getCC) --version \| grep -q "\b${EGIT_COMMIT}" && die \
	"Could not build with PGO profile at sha ${EGIT_COMMIT}".
	echo "Could not build with pgo profile, skipping pgo."
	fi
	fi

	if use llvm_pgo_generate; then
	mycmakeargs+=(
	"-DLLVM_BUILD_INSTRUMENTED=IR"
	)
	fi
	fi

	if ! multilib_is_native_abi \|\| ! use ocaml; then
	mycmakeargs+=(
	"-DOCAMLFIND=NO"
	)
	fi
	# Note: go bindings have no CMake rules at the moment
	# but let's kill the check in case they are introduced
	# if ! multilib_is_native_abi \|\| ! use go; then
	mycmakeargs+=(
	"-DGO_EXECUTABLE=GO_EXECUTABLE-NOTFOUND"
	)
	# fi

	if [[ -z "${CCACHE_DISABLE:-}" ]]; then
	# If ccache is enabled, use it as a compiler launcher. Chances
	# are that folks are iterating on LLVM, and ccache speeds that
	# up substantially.
	mycmakeargs+=(
	"-DCMAKE_C_COMPILER_LAUNCHER=ccache"
	"-DCMAKE_CXX_COMPILER_LAUNCHER=ccache"
	)
	fi

	if multilib_is_native_abi; then
	mycmakeargs+=(
	"-DLLVM_BUILD_DOCS=$(usex doc)"
	"-DLLVM_ENABLE_SPHINX=$(usex doc)"
	"-DLLVM_ENABLE_DOXYGEN=OFF"
	"-DLLVM_INSTALL_HTML=${EPREFIX}/usr/share/doc/${PF}/html"
	"-DSPHINX_WARNINGS_AS_ERRORS=OFF"
	"-DLLVM_INSTALL_UTILS=ON"
	)
	fi

	if ! use debug; then
	append-cppflags -DNDEBUG
	fi

	cmake_src_configure
	}

	multilib_src_compile() {
	# ...If folks are iterating on LLVM with `emerge`, every successful
	# `emerge` invocation will replace their old compiler. Since doing so
	# updates mtimes, we should be focusing on the _content_ of the
	# compiler, rather than the mtime.
	#
	# Note that this is in `src_compile`, since it won't apply if we do it
	# in `src_configure`.
	export CCACHE_COMPILERCHECK=content
	cmake_src_compile

	pax-mark m "${BUILD_DIR}"/bin/llvm-rtdyld
	pax-mark m "${BUILD_DIR}"/bin/lli
	pax-mark m "${BUILD_DIR}"/bin/lli-child-target

	if use test; then
	pax-mark m "${BUILD_DIR}"/unittests/ExecutionEngine/Orc/OrcJITTests
	pax-mark m "${BUILD_DIR}"/unittests/ExecutionEngine/MCJIT/MCJITTests
	pax-mark m "${BUILD_DIR}"/unittests/Support/SupportTests
	fi
	}

	multilib_src_test() {
	# respect TMPDIR!
	local -x LIT_PRESERVES_TMP=1
	cmake_src_test
	}

	src_install() {
	local MULTILIB_CHOST_TOOLS=(
	/usr/bin/llvm-config
	)

	local MULTILIB_WRAPPED_HEADERS=(
	/usr/include/llvm/Config/config.h
	/usr/include/llvm/Config/llvm-config.h
	)

	multilib-minimal_src_install
	}

	# This computes the toolchain SHA that gets baked into our compiler_wrapper
	# binaries. This SHA is potentially nice for uniquely identifying a toolchain,
	# but the most critical purpose that it serves is making the SHA for our
	# compiler_wrapper change with the toolchain that it was installed with. If any
	# of these binaries get modified and we fail to update compiler_wrapper, tools
	# like ccache, ninja, etc might not expect the updates without extra work (thus,
	# cached object files might not be considered stale across compiler updates).
	#
	# Rather than playing whack-a-mole with ways to inform each build system that
	# our compiler has changed (despite its hash remaining identical), we simply
	# modify its hash when any of the binaries it calls may change.
	compute_toolchain_sha() {
	local toolchain_sha_binaries=(
	"bin/clang"
	"bin/clang-tidy"
	"bin/ld.lld"
	)

	# Compute the SHA sums for each of these in parallel, then hash the
	# result. This hash represents all of the (non-header, non-library)
	# dependencies that Clang has.
	#
	# This is expected to be called in a subshell, so don't try to restore
	# pipefail.
	set -o pipefail
	echo "${toolchain_sha_binaries[*]}" \|
	xargs -L1 -P8 sha256sum \|
	sort -k2 \|
	sha256sum - \|
	awk '{print $1}'
	}

	multilib_src_install() {
	cmake_src_install

	local use_llvm_next=false
	if use llvm-next \|\| use llvm-tot
	then
	use_llvm_next=true
	fi
	local wrapper_script=clang_host_wrapper

	local toolchain_sha
	echo "Current directory is $(pwd)"
	toolchain_sha="$(compute_toolchain_sha)" \|\| die
	einfo "Computed toolchain SHA = ${toolchain_sha}"

	local common_wrapper_flags=(
	"--version_suffix=_toolchain_sha_${toolchain_sha}"
	)

	GO111MODULE=off "${FILESDIR}/compiler_wrapper/build.py" --config=cros.host --use_ccache=false \
	--use_llvm_next="${use_llvm_next}" \
	--output_file="${D}/usr/bin/${wrapper_script}" \
	"${common_wrapper_flags[@]}" \|\| die

	newbin "${D}/usr/bin/clang-tidy" "clang-tidy"
	dobin "${FILESDIR}/bisect_driver.py"
	dobin "${FILESDIR}/clang_cc_wrapper"
	exeinto "/usr/bin"
	dosym "${wrapper_script}" "/usr/bin/${CHOST}-clang"
	dosym "${wrapper_script}" "/usr/bin/${CHOST}-clang++"
	newexe "${FILESDIR}/ldwrapper_lld.host" "${CHOST}-ld.lld"

	# llvm-strip is a symlink to llvm-objcopy and distinguished by a argv[0] check.
	# When creating standalone toolchain, argv[0] information is lost and causes
	# llvm-strip invocations to be treated as llvm-objcopy breaking builds
	# (crbug.com/1151787). Handle this by making llvm-strip a full binary.
	if [[ -L "${D}/usr/bin/llvm-strip" ]]; then
	rm "${D}/usr/bin/llvm-strip" \|\| die
	newbin "${D}/usr/bin/llvm-objcopy" "llvm-strip"
	fi

	# Build and install cross-compiler wrappers for supported ABIs.
	# ccache wrapper is used in chroot and non-ccache wrapper is used
	# in standalone SDK.
	local ccache_suffixes=(noccache ccache)
	local ccache_option_values=(false true)
	for ccache_index in {0,1}; do
	local ccache_suffix="${ccache_suffixes[${ccache_index}]}"
	local ccache_option="${ccache_option_values[${ccache_index}]}"
	# Build hardened wrapper written in golang.
	GO111MODULE=off "${FILESDIR}/compiler_wrapper/build.py" --config="cros.hardened" \
	--use_ccache="${ccache_option}" \
	--use_llvm_next="${use_llvm_next}" \
	--output_file="${D}/usr/bin/sysroot_wrapper.hardened.${ccache_suffix}" \
	"${common_wrapper_flags[@]}" \|\| die

	# Build non-hardened wrapper written in golang.
	GO111MODULE=off "${FILESDIR}/compiler_wrapper/build.py" --config="cros.nonhardened" \
	--use_ccache="${ccache_option}" \
	--use_llvm_next="${use_llvm_next}" \
	--output_file="${D}/usr/bin/sysroot_wrapper.${ccache_suffix}" \
	"${common_wrapper_flags[@]}" \|\| die
	done

	local cros_hardened_targets=(
	"aarch64-cros-linux-gnu"
	"armv7a-cros-linux-gnueabihf"
	"i686-cros-linux-gnu"
	"x86_64-cros-linux-gnu"
	)
	local cros_nonhardened_targets=(
	"arm-none-eabi"
	"armv7m-cros-eabi"
	)

	local target
	for target in "${cros_hardened_targets[@]}"; do
	dosym "sysroot_wrapper.hardened.ccache" "/usr/bin/${target}-clang"
	dosym "sysroot_wrapper.hardened.ccache" "/usr/bin/${target}-clang++"
	done
	for target in "${cros_nonhardened_targets[@]}"; do
	dosym "sysroot_wrapper.ccache" "/usr/bin/${target}-clang"
	dosym "sysroot_wrapper.ccache" "/usr/bin/${target}-clang++"
	done

	# Install a symlink bpf-clang which point to clang.
	# Running through symlink will make clang default to bpf target.
	dosym "clang" "/usr/bin/bpf-clang"

	# Remove this file, if it exists, to avoid installation file collision,
	# as this file is also generated/installed by the dev-python/six package.
	find "${D}"/usr -name 'six.py' -delete
	}

	multilib_src_install_all() {
	insinto /usr/share/vim/vimfiles
	doins -r llvm/utils/vim/*/.
	# some users may find it useful
	dodoc llvm/utils/vim/vimrc
	dobin "${S}/compiler-rt/lib/asan/scripts/asan_symbolize.py"
	}

	pkg_postinst() {
	if has_version ">=dev-util/ccache-3.1.9-r2" ; then
	#add ccache links as clang might get installed after ccache
	"${EROOT}"/usr/bin/ccache-config --install-links
	fi
	}

	pkg_postrm() {
	if has_version ">=dev-util/ccache-3.1.9-r2" && [[ -z ${REPLACED_BY_VERSION} ]]; then
	# --remove-links would remove all links, --install-links updates them
	"${EROOT}"/usr/bin/ccache-config --install-links
	fi
	}