sys-devel/llvm/llvm-9.0_pre353983_p20190325.ebuild - mirrors/cros/chromiumos/overlays/chromiumos-overlay - Git at Google

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

 EAPI=5

 : ${CMAKE_MAKEFILE_GENERATOR:=ninja}
 PYTHON_COMPAT=( python2_7 )

 inherit  cros-constants check-reqs cmake-utils eutils flag-o-matic git-2 git-r3 \
 	multilib multilib-minimal python-single-r1 toolchain-funcs pax-utils

 DESCRIPTION="Low Level Virtual Machine"
 HOMEPAGE="http://llvm.org/"
 PROFDATA_FILE="llvm-profdata-20190412.tar.xz"
 SRC_URI="llvm_pgo_use? ( gs://chromeos-localmirror/distfiles/${PROFDATA_FILE} )"
 EGIT_REPO_URI="${CROS_GIT_HOST_URL}/external/github.com/llvm/llvm-project"

 LICENSE="UoI-NCSA"
 SLOT="8"
 KEYWORDS="-* amd64"
 IUSE="debug +default-compiler-rt +default-libcxx doc libedit +libffi llvm-next
 	llvm_pgo_generate +llvm_pgo_use llvm-tot multitarget ncurses ocaml python
 	test +thinlto xml video_cards_radeon"

 COMMON_DEPEND="
 	sys-libs/zlib:0=
 	libedit? ( dev-libs/libedit:0=[${MULTILIB_USEDEP}] )
 	libffi? ( >=virtual/libffi-3.0.13-r1:0=[${MULTILIB_USEDEP}] )
 	ncurses? ( >=sys-libs/ncurses-5.9-r3:5=[${MULTILIB_USEDEP}] )
 	ocaml? (
 		>=dev-lang/ocaml-4.00.0:0=
 		dev-ml/findlib
 		dev-ml/ocaml-ctypes )"
 # configparser-3.2 breaks the build (3.3 or none at all are fine)
 DEPEND="${COMMON_DEPEND}
 	dev-lang/perl
 	>=sys-devel/make-3.81
 	>=sys-devel/flex-2.5.4
 	>=sys-devel/bison-1.875d
 	|| ( >=sys-devel/gcc-3.0 >=sys-devel/llvm-3.5
 		( >=sys-freebsd/freebsd-lib-9.1-r10 sys-libs/libcxx )
 	)
 	|| ( >=sys-devel/binutils-2.18 >=sys-devel/binutils-apple-5.1 )
 	doc? ( dev-python/sphinx )
 	libffi? ( virtual/pkgconfig )
 	!!<dev-python/configparser-3.3.0.2
 	ocaml? ( test? ( dev-ml/ounit ) )
 	${PYTHON_DEPS}"
 RDEPEND="${COMMON_DEPEND}
 	abi_x86_32? ( !<=app-emulation/emul-linux-x86-baselibs-20130224-r2
 		!app-emulation/emul-linux-x86-baselibs[-abi_x86_32(-)] )
 	!<=sys-devel/lld-8.0_pre349610-r5"

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

 pkg_pretend() {
 	# in megs
 	# !clang !debug !multitarget -O2       400
 	# !clang !debug  multitarget -O2       550
 	#  clang !debug !multitarget -O2       950
 	#  clang !debug  multitarget -O2      1200
 	# !clang  debug  multitarget -O2      5G
 	#  clang !debug  multitarget -O0 -g  12G
 	#  clang  debug  multitarget -O2     16G
 	#  clang  debug  multitarget -O0 -g  14G

 	local build_size=550

 	if use debug; then
 		ewarn "USE=debug is known to increase the size of package considerably"
 		ewarn "and cause the tests to fail."
 		ewarn

 		(( build_size *= 14 ))
 	elif is-flagq '-g?(gdb)?([1-9])'; then
 		ewarn "The C++ compiler -g option is known to increase the size of the package"
 		ewarn "considerably. If you run out of space, please consider removing it."
 		ewarn

 		(( build_size *= 10 ))
 	fi

 	# Multiply by number of ABIs :).
 	local abis=( $(multilib_get_enabled_abis) )
 	(( build_size *= ${#abis[@]} ))

 	local CHECKREQS_DISK_BUILD=${build_size}M
 	check-reqs_pkg_pretend

 	if [[ ${MERGE_TYPE} != binary ]]; then
 		echo 'int main() {return 0;}' > "${T}"/test.cxx || die
 		ebegin "Trying to build a C++11 test program"
 		if ! $(tc-getCXX) -std=c++11 -o /dev/null "${T}"/test.cxx; then
 			eerror "LLVM-${PV} requires C++11-capable C++ compiler. Your current compiler"
 			eerror "does not seem to support -std=c++11 option. Please upgrade your compiler"
 			eerror "to gcc-4.7 or an equivalent version supporting C++11."
 			die "Currently active compiler does not support -std=c++11"
 		fi
 		eend ${?}
 	fi
 }

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

 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
 }

 src_unpack() {
 	local llvm_hash

 	if use llvm-tot; then
 		llvm_hash="origin/master"
 	elif use llvm-next; then
 		# llvm:353983 https://critique.corp.google.com/#review/233864070
 		llvm_hash="de7a0a152648d1a74cf4319920b1848aa00d1ca3" # EGIT_COMMIT r353983
 	else
 		# llvm:353983 https://critique.corp.google.com/#review/233864070
 		llvm_hash="de7a0a152648d1a74cf4319920b1848aa00d1ca3" # EGIT_COMMIT r353983
 	fi

 	# Don't unpack profdata file when calling git-2_src_unpack.
 	EGIT_NOUNPACK=1

 	# Unpack llvm
 	ESVN_PROJECT="llvm"
 	EGIT_COMMIT="${llvm_hash}"
 	git-2_src_unpack

 	if use llvm_pgo_use; then
 		cd ${WORKDIR}
 		unpack ${PROFDATA_FILE}
 	fi
 	EGIT_NOUNPACK=
 }

 pick_cherries() {
 	local CHERRIES=""
 	# clang

 	# llvm
 	CHERRIES+=" d0b1f30b32bda78267a48f1812adabcfe872fe43" #r354062
 	CHERRIES+=" 74b874ac4c6c079f85edd1f2957b1d96e0127ea5" #r356988

 	# compiler-rt
 	CHERRIES+=" a2062b222d93e2ae86d36ec75923c8b1e4ae0d81" #r354632
 	CHERRIES+=" e3b6d11038f3927fd02ec6d5459cfd0ffbe6b2fe" #r354989, needed to pick r355030
 	CHERRIES+=" f46a52b5363d22bba6cc6081da295ece181977f2" #r355030
 	CHERRIES+=" f6b0a14bff33f85087e9cc5c3b1bb00f58ed8b8b" #r355041
 	CHERRIES+=" d4b4e17d2c70c8d498ad33422cf847d659b5b0cf" #r355064
 	CHERRIES+=" 37ce064082c6c8283829f206af55ff6a28e95544" #r355125
 	CHERRIES+=" 86724e40bfa544a5024a2a3d522934aef6914cc7" #r356581

 	# lld
 	CHERRIES+=" 432030e843bf124b4d285874362b6fd00446dd56" #r357133
 	CHERRIES+=" 3ce9af9370d091b7d959902216482f3015e965fc" #r357160

 	for cherry in ${CHERRIES}; do
 		epatch "${FILESDIR}/cherry/${cherry}.patch"
 	done
 }

 pick_next_cherries() {
 	local CHERRIES=""

 	# clang

 	# llvm
 	CHERRIES+=" d0b1f30b32bda78267a48f1812adabcfe872fe43" #r354062
 	CHERRIES+=" 74b874ac4c6c079f85edd1f2957b1d96e0127ea5" #r356988

 	# compiler-rt
 	CHERRIES+=" a2062b222d93e2ae86d36ec75923c8b1e4ae0d81" #r354632
 	CHERRIES+=" e3b6d11038f3927fd02ec6d5459cfd0ffbe6b2fe" #r354989, needed to pick r355030
 	CHERRIES+=" f46a52b5363d22bba6cc6081da295ece181977f2" #r355030
 	CHERRIES+=" f6b0a14bff33f85087e9cc5c3b1bb00f58ed8b8b" #r355041
 	CHERRIES+=" d4b4e17d2c70c8d498ad33422cf847d659b5b0cf" #r355064
 	CHERRIES+=" 37ce064082c6c8283829f206af55ff6a28e95544" #r355125
 	CHERRIES+=" 86724e40bfa544a5024a2a3d522934aef6914cc7" #r356581

 	#lld
 	CHERRIES+=" 432030e843bf124b4d285874362b6fd00446dd56" #r357133
 	CHERRIES+=" 3ce9af9370d091b7d959902216482f3015e965fc" #r357160

 	for cherry in ${CHERRIES}; do
 		epatch "${FILESDIR}/cherry/${cherry}.patch"
 	done
 }

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

 	# Tries to parse the last revision ID present in the most recent commit
 	# with a revision ID attached. We can't simply `grep -m 1`, since it's
 	# reasonable for a revert message to include the git-svn-id of the
 	# commit it's reverting.
 	#
 	# Thankfully, LLVM's machinery always makes this ID the last line of
 	# each upstream commit, so we just need to search for it, with commit
 	# two lines later.
 	#
 	# Example of revision ID line:
 	# llvm-svn: 358929
 	#
 	# Where 358929 is the revision.
 	git -C "${subdir}" log | \
 		awk '
 			/^commit/ {
 				if (most_recent_id != "") {
 					print most_recent_id
 					exit
 				}
 			}
 			/^\s+llvm-svn: [0-9]+$/ { most_recent_id = $2 }'
 }

 # This cache is a bit awkward, since the most natural way to do this is "make a
 # get_most_recent_revision function, and call it in a subshell." Subshells make
 # caching worthless. :)
 most_recent_revision=

 ensure_most_recent_revision_set() {
 	if test -z "$most_recent_revision"; then
 		most_recent_revision="$(get_most_recent_revision)"
 	fi
 }

 epatch_between() {
 	local min_revision="$1"
 	local max_revision="$2"
 	local patch="$3"

 	ensure_most_recent_revision_set

 	if test "$min_revision" -le "$most_recent_revision" -a \
 			"$max_revision" -ge "$most_recent_revision"; then
 		epatch "$patch"
 	else
 		einfo "Patch $3 not applied"
 		return 1
 	fi
 }

 epatch_after() {
 	epatch_between $1 9999999 $2
 }

 epatch_before() {
 	epatch_between 0 $1 $2
 }

 src_prepare() {
 	if ! use llvm-tot ; then
 		use llvm-next || pick_cherries
 		use llvm-next && pick_next_cherries
 	fi

 	# compiler-rt patches
 	epatch "${FILESDIR}"/llvm-next-leak-whitelist.patch
 	epatch "${FILESDIR}"/clang-4.0-asan-default-path.patch

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

 	# llvm patches
 	# Allow custom cmake build types (like 'Gentoo')
 	epatch "${FILESDIR}"/cmake/${PN}-3.8-allow_custom_cmake_build_types.patch

 	# crbug/591436
 	epatch "${FILESDIR}"/llvm-8.0-clang-executable-detection.patch

 	epatch "${FILESDIR}"/llvm-3.9-dwarf-version.patch

 	# Temporarily revert r332058 as it caused speedometer2 perf regression.
 	# https://crbug.com/864781
 	epatch_after 332058 "${FILESDIR}"/llvm-8.0-next-revert-afdo-hotness.patch

 	# Revert r335145 and r335284 since android reverts them.
 	# b/113573336
 	epatch_after 335145 "${FILESDIR}"/llvm-8.0-revert-r335145.patch

 	# clang patches
 	# clang: crbug/606391
 	epatch "${FILESDIR}"/${PN}-3.8-invocation.patch

 	# Link libgcc_eh when using compiler-rt as default rtlib.
 	# https://llvm.org/bugs/show_bug.cgi?id=28681
 	epatch "${FILESDIR}"/clang-6.0-enable-libgcc-with-compiler-rt.patch

 	epatch "${FILESDIR}"/clang-next-8.0-revert-r335284.patch

 	# revert r344218, https://crbug.com/915711
 	epatch "${FILESDIR}"/llvm-8.0-revert-headers-as-sources.patch
 	# revert r340839, https://crbug.com/916740
 	epatch "${FILESDIR}"/llvm-8.0-revert-asm-debug-info.patch

 	# lld patches
 	# These 2 patches are still reverted in Android.
 	epatch "${FILESDIR}"/lld-8.0-revert-r326242.patch
 	epatch "${FILESDIR}"/lld-8.0-revert-r325849.patch
 	# Allow .elf suffix in lld binary name.
 	epatch "${FILESDIR}/lld-invoke-name.patch"
 	# Put .text.hot section before .text section.
 	epatch "${FILESDIR}"/lld-8.0-reorder-hotsection-early.patch

 	python_setup

 	# User patches
 	epatch_user

 	# Native libdir is used to hold LLVMgold.so
 	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() {
 	local targets
 	if use multitarget; then
 		targets='host;X86;ARM;AArch64;NVPTX'
 	else
 		targets='host;CppBackend'
 		use video_cards_radeon && targets+=';AMDGPU'
 	fi

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

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

 		-DLLVM_BUILD_LLVM_DYLIB=ON
 		# Link LLVM statically
 		-DLLVM_LINK_LLVM_DYLIB=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 "")
 	)

 	# Update LLVM to 9.0 will cause LLVM to complain GCC
 	# version is < 5.1. Add this flag to suppress the error.
 	mycmakeargs+=(
 		-DLLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN=1
 	)

 	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
 			)
 		fi

 		# TODO: specify different profdata for llvm-next.
 		if use llvm_pgo_use; then
 			mycmakeargs+=(
 				-DLLVM_PROFDATA_FILE="${WORKDIR}/llvm.profdata"
 			)
 		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 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

 	cmake-utils_src_configure
 }

 multilib_src_compile() {
 	cmake-utils_src_compile
 	# TODO: not sure why this target is not correctly called
 	multilib_is_native_abi && use doc && use ocaml && cmake-utils_src_make docs/ocaml_doc

 	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
 	local test_targets=( check )
 	cmake-utils_src_make "${test_targets[@]}"
 }

 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
 }

 multilib_src_install() {
 	cmake-utils_src_install

 	local wrapper_script=clang_host_wrapper
 	cat "${FILESDIR}/clang_host_wrapper.header" \
 		"${FILESDIR}/wrapper_script_common" \
 		"${FILESDIR}/clang_host_wrapper.body" > \
 		"${D}/usr/bin/${wrapper_script}" || die
 	chmod 755 "${D}/usr/bin/${wrapper_script}" || die
 	newbin "${D}/usr/bin/clang-tidy" "clang-tidy"
 	dobin "${FILESDIR}/bisect_driver.py"
 	dobin "${FILESDIR}/clang-tidy-parse-build-log.py"
 	dobin "${FILESDIR}/clang-tidy-warn.py"
 	dobin "${FILESDIR}/clang_tidy_execute.py"
 	exeinto "/usr/bin"
 	dosym "${wrapper_script}" "/usr/bin/${CHOST}-clang"
 	dosym "${wrapper_script}" "/usr/bin/${CHOST}-clang++"
 	mv "${D}/usr/bin/lld" "${D}/usr/bin/lld.real" || die
 	newexe "${FILESDIR}/ldwrapper" "lld" || die
 }

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

	EAPI=5

	: ${CMAKE_MAKEFILE_GENERATOR:=ninja}
	PYTHON_COMPAT=( python2_7 )

	inherit cros-constants check-reqs cmake-utils eutils flag-o-matic git-2 git-r3 \
	multilib multilib-minimal python-single-r1 toolchain-funcs pax-utils

	DESCRIPTION="Low Level Virtual Machine"
	HOMEPAGE="http://llvm.org/"
	PROFDATA_FILE="llvm-profdata-20190412.tar.xz"
	SRC_URI="llvm_pgo_use? ( gs://chromeos-localmirror/distfiles/${PROFDATA_FILE} )"
	EGIT_REPO_URI="${CROS_GIT_HOST_URL}/external/github.com/llvm/llvm-project"

	LICENSE="UoI-NCSA"
	SLOT="8"
	KEYWORDS="-* amd64"
	IUSE="debug +default-compiler-rt +default-libcxx doc libedit +libffi llvm-next
	llvm_pgo_generate +llvm_pgo_use llvm-tot multitarget ncurses ocaml python
	test +thinlto xml video_cards_radeon"

	COMMON_DEPEND="
	sys-libs/zlib:0=
	libedit? ( dev-libs/libedit:0=[${MULTILIB_USEDEP}] )
	libffi? ( >=virtual/libffi-3.0.13-r1:0=[${MULTILIB_USEDEP}] )
	ncurses? ( >=sys-libs/ncurses-5.9-r3:5=[${MULTILIB_USEDEP}] )
	ocaml? (
	>=dev-lang/ocaml-4.00.0:0=
	dev-ml/findlib
	dev-ml/ocaml-ctypes )"
	# configparser-3.2 breaks the build (3.3 or none at all are fine)
	DEPEND="${COMMON_DEPEND}
	dev-lang/perl
	>=sys-devel/make-3.81
	>=sys-devel/flex-2.5.4
	>=sys-devel/bison-1.875d
	\|\| ( >=sys-devel/gcc-3.0 >=sys-devel/llvm-3.5
	( >=sys-freebsd/freebsd-lib-9.1-r10 sys-libs/libcxx )
	)
	\|\| ( >=sys-devel/binutils-2.18 >=sys-devel/binutils-apple-5.1 )
	doc? ( dev-python/sphinx )
	libffi? ( virtual/pkgconfig )
	!!<dev-python/configparser-3.3.0.2
	ocaml? ( test? ( dev-ml/ounit ) )
	${PYTHON_DEPS}"
	RDEPEND="${COMMON_DEPEND}
	abi_x86_32? ( !<=app-emulation/emul-linux-x86-baselibs-20130224-r2
	!app-emulation/emul-linux-x86-baselibs[-abi_x86_32(-)] )
	!<=sys-devel/lld-8.0_pre349610-r5"

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

	pkg_pretend() {
	# in megs
	# !clang !debug !multitarget -O2 400
	# !clang !debug multitarget -O2 550
	# clang !debug !multitarget -O2 950
	# clang !debug multitarget -O2 1200
	# !clang debug multitarget -O2 5G
	# clang !debug multitarget -O0 -g 12G
	# clang debug multitarget -O2 16G
	# clang debug multitarget -O0 -g 14G

	local build_size=550

	if use debug; then
	ewarn "USE=debug is known to increase the size of package considerably"
	ewarn "and cause the tests to fail."
	ewarn

	(( build_size *= 14 ))
	elif is-flagq '-g?(gdb)?([1-9])'; then
	ewarn "The C++ compiler -g option is known to increase the size of the package"
	ewarn "considerably. If you run out of space, please consider removing it."
	ewarn

	(( build_size *= 10 ))
	fi

	# Multiply by number of ABIs :).
	local abis=( $(multilib_get_enabled_abis) )
	(( build_size *= ${#abis[@]} ))

	local CHECKREQS_DISK_BUILD=${build_size}M
	check-reqs_pkg_pretend

	if [[ ${MERGE_TYPE} != binary ]]; then
	echo 'int main() {return 0;}' > "${T}"/test.cxx \|\| die
	ebegin "Trying to build a C++11 test program"
	if ! $(tc-getCXX) -std=c++11 -o /dev/null "${T}"/test.cxx; then
	eerror "LLVM-${PV} requires C++11-capable C++ compiler. Your current compiler"
	eerror "does not seem to support -std=c++11 option. Please upgrade your compiler"
	eerror "to gcc-4.7 or an equivalent version supporting C++11."
	die "Currently active compiler does not support -std=c++11"
	fi
	eend ${?}
	fi
	}

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

	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
	}

	src_unpack() {
	local llvm_hash

	if use llvm-tot; then
	llvm_hash="origin/master"
	elif use llvm-next; then
	# llvm:353983 https://critique.corp.google.com/#review/233864070
	llvm_hash="de7a0a152648d1a74cf4319920b1848aa00d1ca3" # EGIT_COMMIT r353983
	else
	# llvm:353983 https://critique.corp.google.com/#review/233864070
	llvm_hash="de7a0a152648d1a74cf4319920b1848aa00d1ca3" # EGIT_COMMIT r353983
	fi

	# Don't unpack profdata file when calling git-2_src_unpack.
	EGIT_NOUNPACK=1

	# Unpack llvm
	ESVN_PROJECT="llvm"
	EGIT_COMMIT="${llvm_hash}"
	git-2_src_unpack

	if use llvm_pgo_use; then
	cd ${WORKDIR}
	unpack ${PROFDATA_FILE}
	fi
	EGIT_NOUNPACK=
	}

	pick_cherries() {
	local CHERRIES=""
	# clang

	# llvm
	CHERRIES+=" d0b1f30b32bda78267a48f1812adabcfe872fe43" #r354062
	CHERRIES+=" 74b874ac4c6c079f85edd1f2957b1d96e0127ea5" #r356988

	# compiler-rt
	CHERRIES+=" a2062b222d93e2ae86d36ec75923c8b1e4ae0d81" #r354632
	CHERRIES+=" e3b6d11038f3927fd02ec6d5459cfd0ffbe6b2fe" #r354989, needed to pick r355030
	CHERRIES+=" f46a52b5363d22bba6cc6081da295ece181977f2" #r355030
	CHERRIES+=" f6b0a14bff33f85087e9cc5c3b1bb00f58ed8b8b" #r355041
	CHERRIES+=" d4b4e17d2c70c8d498ad33422cf847d659b5b0cf" #r355064
	CHERRIES+=" 37ce064082c6c8283829f206af55ff6a28e95544" #r355125
	CHERRIES+=" 86724e40bfa544a5024a2a3d522934aef6914cc7" #r356581

	# lld
	CHERRIES+=" 432030e843bf124b4d285874362b6fd00446dd56" #r357133
	CHERRIES+=" 3ce9af9370d091b7d959902216482f3015e965fc" #r357160

	for cherry in ${CHERRIES}; do
	epatch "${FILESDIR}/cherry/${cherry}.patch"
	done
	}

	pick_next_cherries() {
	local CHERRIES=""

	# clang

	# llvm
	CHERRIES+=" d0b1f30b32bda78267a48f1812adabcfe872fe43" #r354062
	CHERRIES+=" 74b874ac4c6c079f85edd1f2957b1d96e0127ea5" #r356988

	# compiler-rt
	CHERRIES+=" a2062b222d93e2ae86d36ec75923c8b1e4ae0d81" #r354632
	CHERRIES+=" e3b6d11038f3927fd02ec6d5459cfd0ffbe6b2fe" #r354989, needed to pick r355030
	CHERRIES+=" f46a52b5363d22bba6cc6081da295ece181977f2" #r355030
	CHERRIES+=" f6b0a14bff33f85087e9cc5c3b1bb00f58ed8b8b" #r355041
	CHERRIES+=" d4b4e17d2c70c8d498ad33422cf847d659b5b0cf" #r355064
	CHERRIES+=" 37ce064082c6c8283829f206af55ff6a28e95544" #r355125
	CHERRIES+=" 86724e40bfa544a5024a2a3d522934aef6914cc7" #r356581

	#lld
	CHERRIES+=" 432030e843bf124b4d285874362b6fd00446dd56" #r357133
	CHERRIES+=" 3ce9af9370d091b7d959902216482f3015e965fc" #r357160

	for cherry in ${CHERRIES}; do
	epatch "${FILESDIR}/cherry/${cherry}.patch"
	done
	}

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

	# Tries to parse the last revision ID present in the most recent commit
	# with a revision ID attached. We can't simply `grep -m 1`, since it's
	# reasonable for a revert message to include the git-svn-id of the
	# commit it's reverting.
	#
	# Thankfully, LLVM's machinery always makes this ID the last line of
	# each upstream commit, so we just need to search for it, with commit
	# two lines later.
	#
	# Example of revision ID line:
	# llvm-svn: 358929
	#
	# Where 358929 is the revision.
	git -C "${subdir}" log \| \
	awk '
	/^commit/ {
	if (most_recent_id != "") {
	print most_recent_id
	exit
	}
	}
	/^\s+llvm-svn: [0-9]+$/ { most_recent_id = $2 }'
	}

	# This cache is a bit awkward, since the most natural way to do this is "make a
	# get_most_recent_revision function, and call it in a subshell." Subshells make
	# caching worthless. :)
	most_recent_revision=

	ensure_most_recent_revision_set() {
	if test -z "$most_recent_revision"; then
	most_recent_revision="$(get_most_recent_revision)"
	fi
	}

	epatch_between() {
	local min_revision="$1"
	local max_revision="$2"
	local patch="$3"

	ensure_most_recent_revision_set

	if test "$min_revision" -le "$most_recent_revision" -a \
	"$max_revision" -ge "$most_recent_revision"; then
	epatch "$patch"
	else
	einfo "Patch $3 not applied"
	return 1
	fi
	}

	epatch_after() {
	epatch_between $1 9999999 $2
	}

	epatch_before() {
	epatch_between 0 $1 $2
	}

	src_prepare() {
	if ! use llvm-tot ; then
	use llvm-next \|\| pick_cherries
	use llvm-next && pick_next_cherries
	fi

	# compiler-rt patches
	epatch "${FILESDIR}"/llvm-next-leak-whitelist.patch
	epatch "${FILESDIR}"/clang-4.0-asan-default-path.patch

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

	# llvm patches
	# Allow custom cmake build types (like 'Gentoo')
	epatch "${FILESDIR}"/cmake/${PN}-3.8-allow_custom_cmake_build_types.patch

	# crbug/591436
	epatch "${FILESDIR}"/llvm-8.0-clang-executable-detection.patch

	epatch "${FILESDIR}"/llvm-3.9-dwarf-version.patch

	# Temporarily revert r332058 as it caused speedometer2 perf regression.
	# https://crbug.com/864781
	epatch_after 332058 "${FILESDIR}"/llvm-8.0-next-revert-afdo-hotness.patch

	# Revert r335145 and r335284 since android reverts them.
	# b/113573336
	epatch_after 335145 "${FILESDIR}"/llvm-8.0-revert-r335145.patch

	# clang patches
	# clang: crbug/606391
	epatch "${FILESDIR}"/${PN}-3.8-invocation.patch

	# Link libgcc_eh when using compiler-rt as default rtlib.
	# https://llvm.org/bugs/show_bug.cgi?id=28681
	epatch "${FILESDIR}"/clang-6.0-enable-libgcc-with-compiler-rt.patch

	epatch "${FILESDIR}"/clang-next-8.0-revert-r335284.patch

	# revert r344218, https://crbug.com/915711
	epatch "${FILESDIR}"/llvm-8.0-revert-headers-as-sources.patch
	# revert r340839, https://crbug.com/916740
	epatch "${FILESDIR}"/llvm-8.0-revert-asm-debug-info.patch

	# lld patches
	# These 2 patches are still reverted in Android.
	epatch "${FILESDIR}"/lld-8.0-revert-r326242.patch
	epatch "${FILESDIR}"/lld-8.0-revert-r325849.patch
	# Allow .elf suffix in lld binary name.
	epatch "${FILESDIR}/lld-invoke-name.patch"
	# Put .text.hot section before .text section.
	epatch "${FILESDIR}"/lld-8.0-reorder-hotsection-early.patch

	python_setup

	# User patches
	epatch_user

	# Native libdir is used to hold LLVMgold.so
	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() {
	local targets
	if use multitarget; then
	targets='host;X86;ARM;AArch64;NVPTX'
	else
	targets='host;CppBackend'
	use video_cards_radeon && targets+=';AMDGPU'
	fi

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

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

	-DLLVM_BUILD_LLVM_DYLIB=ON
	# Link LLVM statically
	-DLLVM_LINK_LLVM_DYLIB=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 "")
	)

	# Update LLVM to 9.0 will cause LLVM to complain GCC
	# version is < 5.1. Add this flag to suppress the error.
	mycmakeargs+=(
	-DLLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN=1
	)

	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
	)
	fi

	# TODO: specify different profdata for llvm-next.
	if use llvm_pgo_use; then
	mycmakeargs+=(
	-DLLVM_PROFDATA_FILE="${WORKDIR}/llvm.profdata"
	)
	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 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

	cmake-utils_src_configure
	}

	multilib_src_compile() {
	cmake-utils_src_compile
	# TODO: not sure why this target is not correctly called
	multilib_is_native_abi && use doc && use ocaml && cmake-utils_src_make docs/ocaml_doc

	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
	local test_targets=( check )
	cmake-utils_src_make "${test_targets[@]}"
	}

	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
	}

	multilib_src_install() {
	cmake-utils_src_install

	local wrapper_script=clang_host_wrapper
	cat "${FILESDIR}/clang_host_wrapper.header" \
	"${FILESDIR}/wrapper_script_common" \
	"${FILESDIR}/clang_host_wrapper.body" > \
	"${D}/usr/bin/${wrapper_script}" \|\| die
	chmod 755 "${D}/usr/bin/${wrapper_script}" \|\| die
	newbin "${D}/usr/bin/clang-tidy" "clang-tidy"
	dobin "${FILESDIR}/bisect_driver.py"
	dobin "${FILESDIR}/clang-tidy-parse-build-log.py"
	dobin "${FILESDIR}/clang-tidy-warn.py"
	dobin "${FILESDIR}/clang_tidy_execute.py"
	exeinto "/usr/bin"
	dosym "${wrapper_script}" "/usr/bin/${CHOST}-clang"
	dosym "${wrapper_script}" "/usr/bin/${CHOST}-clang++"
	mv "${D}/usr/bin/lld" "${D}/usr/bin/lld.real" \|\| die
	newexe "${FILESDIR}/ldwrapper" "lld" \|\| die
	}

	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"
	}