# Copyright 1999-2017 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2
# $Id$

EAPI=6

: ${CMAKE_MAKEFILE_GENERATOR:=ninja}
# (needed due to CMAKE_BUILD_TYPE != Gentoo)
CMAKE_MIN_VERSION=3.7.0-r1
PYTHON_COMPAT=( python2_7 )

inherit check-reqs cmake-utils flag-o-matic \
	multilib-minimal pax-utils python-any-r1 toolchain-funcs versionator

DESCRIPTION="Low Level Virtual Machine"
HOMEPAGE="http://llvm.org/"
SRC_URI="http://www.llvm.org/pre-releases/${PV/_//}/${P/_/}.src.tar.xz"

# Keep in sync with CMakeLists.txt
ALL_LLVM_TARGETS=( AArch64 AMDGPU ARM BPF Hexagon Lanai Mips MSP430
	NVPTX PowerPC RISCV Sparc SystemZ X86 XCore )
ALL_LLVM_TARGETS=( "${ALL_LLVM_TARGETS[@]/#/llvm_targets_}" )

# Additional licenses:
# 1. OpenBSD regex: Henry Spencer's license ('rc' in Gentoo) + BSD.
# 2. ARM backend: LLVM Software Grant by ARM.
# 3. MD5 code: public-domain.
# 4. Tests (not installed):
#  a. gtest: BSD.
#  b. YAML tests: MIT.

LICENSE="UoI-NCSA rc BSD public-domain
	llvm_targets_ARM? ( LLVM-Grant )"
SLOT="$(get_major_version)"
KEYWORDS="~amd64 ~arm64 ~x86"
IUSE="debug +doc gold libedit +libffi multitarget ncurses test
	elibc_musl kernel_Darwin ${ALL_LLVM_TARGETS[*]}"

RDEPEND="
	sys-libs/zlib:0=
	gold? ( >=sys-devel/binutils-2.22:*[cxx] )
	libedit? ( dev-libs/libedit:0=[${MULTILIB_USEDEP}] )
	libffi? ( >=virtual/libffi-3.0.13-r1:0=[${MULTILIB_USEDEP}] )
	ncurses? ( >=sys-libs/ncurses-5.9-r3:0=[${MULTILIB_USEDEP}] )"
# configparser-3.2 breaks the build (3.3 or none at all are fine)
DEPEND="${RDEPEND}
	dev-lang/perl
	|| ( >=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 )
	kernel_Darwin? ( <sys-libs/libcxx-$(get_version_component_range 1-3).9999 )
	doc? ( dev-python/sphinx )
	gold? ( sys-libs/binutils-libs )
	libffi? ( virtual/pkgconfig )
	test? ( $(python_gen_any_dep "~dev-python/lit-${PV}[\${PYTHON_USEDEP}]") )
	!!<dev-python/configparser-3.3.0.2
	${PYTHON_DEPS}"
# There are no file collisions between these versions but having :0
# installed means llvm-config there will take precedence.
RDEPEND="${RDEPEND}
	!sys-devel/llvm:0"
PDEPEND="app-vim/llvm-vim
	gold? ( sys-devel/llvmgold )"

REQUIRED_USE="${PYTHON_REQUIRED_USE}
	|| ( ${ALL_LLVM_TARGETS[*]} )
	multitarget? ( ${ALL_LLVM_TARGETS[*]} )"

S=${WORKDIR}/${P/_/}.src

# least intrusive of all
CMAKE_BUILD_TYPE=RelWithDebInfo

python_check_deps() {
	! use test \
		|| has_version "dev-python/lit[${PYTHON_USEDEP}]"
}

check_space() {
	# in megs
	# !debug !multitarget -O2       400
	# !debug  multitarget -O2       550
	#  debug  multitarget -O2      5G

	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
}

pkg_pretend() {
	check_space
}

pkg_setup() {
	check_space
}

src_prepare() {
	# Python is needed to run tests using lit
	python_setup

	# Fix llvm-config for shared linking and sane flags
	# https://bugs.gentoo.org/show_bug.cgi?id=565358
	eapply "${FILESDIR}"/9999/0007-llvm-config-Clean-up-exported-values-update-for-shar.patch

	# support building llvm against musl-libc
	use elibc_musl && eapply "${FILESDIR}"/9999/musl-fixes.patch

	# disable use of SDK on OSX, bug #568758
	sed -i -e 's/xcrun/false/' utils/lit/lit/util.py || die

	# User patches
	eapply_user
}

multilib_src_configure() {
	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=$(get_libdir)
	local mycmakeargs=(
		-DCMAKE_INSTALL_PREFIX="${EPREFIX}/usr/lib/llvm/${SLOT}"
		-DLLVM_LIBDIR_SUFFIX=${libdir#lib}

		-DBUILD_SHARED_LIBS=ON
		-DLLVM_TARGETS_TO_BUILD="${LLVM_TARGETS// /;}"
		-DLLVM_BUILD_TESTS=$(usex test)

		-DLLVM_ENABLE_FFI=$(usex libffi)
		-DLLVM_ENABLE_LIBEDIT=$(usex libedit)
		-DLLVM_ENABLE_TERMINFO=$(usex ncurses)
		-DLLVM_ENABLE_ASSERTIONS=$(usex debug)
		-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}"

		# disable OCaml bindings (now in dev-ml/llvm-ocaml)
		-DOCAMLFIND=NO
	)

#	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

	use test && mycmakeargs+=(
		-DLIT_COMMAND="${EPREFIX}/usr/bin/lit"
	)

	if multilib_is_native_abi; then
		mycmakeargs+=(
			-DLLVM_BUILD_DOCS=$(usex doc)
			-DLLVM_ENABLE_OCAMLDOC=OFF
			-DLLVM_ENABLE_SPHINX=$(usex doc)
			-DLLVM_ENABLE_DOXYGEN=OFF
			-DLLVM_INSTALL_UTILS=ON
		)
		use doc && mycmakeargs+=(
			-DLLVM_INSTALL_SPHINX_HTML_DIR="${EPREFIX}/usr/share/doc/${PF}/html"
			-DSPHINX_WARNINGS_AS_ERRORS=OFF
		)
		use gold && mycmakeargs+=(
			-DLLVM_BINUTILS_INCDIR="${EPREFIX}"/usr/include
		)
	fi

	if tc-is-cross-compiler; then
		[[ -x "/usr/bin/llvm-tblgen" ]] \
			|| die "/usr/bin/llvm-tblgen not found or usable"
		mycmakeargs+=(
			-DCMAKE_CROSSCOMPILING=ON
			-DLLVM_TABLEGEN=/usr/bin/llvm-tblgen
		)
	fi

	cmake-utils_src_configure
}

multilib_src_compile() {
	cmake-utils_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-utils_src_make check
}

src_install() {
	local MULTILIB_CHOST_TOOLS=(
		/usr/lib/llvm/${SLOT}/bin/llvm-config
	)

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

	local LLVM_LDPATHS=()
	multilib-minimal_src_install

	# move wrapped headers back
	mv "${ED%/}"/usr/include "${ED%/}"/usr/lib/llvm/${SLOT}/include || die
}

multilib_src_install() {
	cmake-utils_src_install

	# move headers to /usr/include for wrapping
	rm -rf "${ED%/}"/usr/include || die
	mv "${ED%/}"/usr/lib/llvm/${SLOT}/include "${ED%/}"/usr/include || die

	LLVM_LDPATHS+=( "${EPREFIX}/usr/lib/llvm/${SLOT}/$(get_libdir)" )
}

multilib_src_install_all() {
	local revord=$(( 9999 - ${SLOT} ))
	cat <<-_EOF_ > "${T}/10llvm-${revord}" || die
		PATH="${EPREFIX}/usr/lib/llvm/${SLOT}/bin"
		# we need to duplicate it in ROOTPATH for Portage to respect...
		ROOTPATH="${EPREFIX}/usr/lib/llvm/${SLOT}/bin"
		LDPATH="$( IFS=:; echo "${LLVM_LDPATHS[*]}" )"
_EOF_
	doenvd "${T}/10llvm-${revord}"
}