sys-devel/llvm: Backport X86 codegen bugfix for Chromium builds
authorMichał Górny <mgorny@gentoo.org>
Tue, 2 Oct 2018 17:56:57 +0000 (19:56 +0200)
committerMichał Górny <mgorny@gentoo.org>
Tue, 2 Oct 2018 18:40:55 +0000 (20:40 +0200)
Backport the X86 codegen fix to 7.0.0 and 6.0.1, to ~arch.  Hopefully
people will get this along with libffi-enforced rebuild.  We can
stabilize 6.0.1-r2 either when stable users start hitting this, or when
libffi gets stable.

Bug: https://bugs.gentoo.org/664868
Signed-off-by: Michał Górny <mgorny@gentoo.org>
sys-devel/llvm/files/7.0.0/0001-X86-Stop-X86DomainReassignment-from-creating-copies-.patch [new file with mode: 0644]
sys-devel/llvm/llvm-6.0.1-r2.ebuild [new file with mode: 0644]
sys-devel/llvm/llvm-7.0.0-r1.ebuild [new file with mode: 0644]

diff --git a/sys-devel/llvm/files/7.0.0/0001-X86-Stop-X86DomainReassignment-from-creating-copies-.patch b/sys-devel/llvm/files/7.0.0/0001-X86-Stop-X86DomainReassignment-from-creating-copies-.patch
new file mode 100644 (file)
index 0000000..f38907c
--- /dev/null
@@ -0,0 +1,110 @@
+From 72da952b396f43d2ce6ca20a0f0d75212fea6b28 Mon Sep 17 00:00:00 2001
+From: Craig Topper <craig.topper@intel.com>
+Date: Mon, 1 Oct 2018 07:08:41 +0000
+Subject: [PATCH] [X86] Stop X86DomainReassignment from creating copies between
+ GR8/GR16 physical registers and k-registers.
+
+We can only copy between a k-register and a GR32/GR64 register.
+
+This patch detects that the copy will be illegal and prevents the domain reassignment from happening for that closure.
+
+This probably isn't the best fix, and we should probably figure out how to handle this correctly.
+
+Fixes PR38803.
+
+git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@343443 91177308-0d34-0410-b5e6-96231b3b80d8
+---
+ lib/Target/X86/X86DomainReassignment.cpp | 21 +++++++++++
+ test/CodeGen/X86/pr38803.ll              | 48 ++++++++++++++++++++++++
+ 2 files changed, 69 insertions(+)
+ create mode 100644 test/CodeGen/X86/pr38803.ll
+
+diff --git a/lib/Target/X86/X86DomainReassignment.cpp b/lib/Target/X86/X86DomainReassignment.cpp
+index 5196446b39e..62588e9509d 100644
+--- a/lib/Target/X86/X86DomainReassignment.cpp
++++ b/lib/Target/X86/X86DomainReassignment.cpp
+@@ -217,6 +217,27 @@ public:
+   InstrCOPYReplacer(unsigned SrcOpcode, RegDomain DstDomain, unsigned DstOpcode)
+       : InstrReplacer(SrcOpcode, DstOpcode), DstDomain(DstDomain) {}
++  bool isLegal(const MachineInstr *MI,
++               const TargetInstrInfo *TII) const override {
++    if (!InstrConverterBase::isLegal(MI, TII))
++      return false;
++
++    // Don't allow copies to/flow GR8/GR16 physical registers.
++    // FIXME: Is there some better way to support this?
++    unsigned DstReg = MI->getOperand(0).getReg();
++    if (TargetRegisterInfo::isPhysicalRegister(DstReg) &&
++        (X86::GR8RegClass.contains(DstReg) ||
++         X86::GR16RegClass.contains(DstReg)))
++      return false;
++    unsigned SrcReg = MI->getOperand(1).getReg();
++    if (TargetRegisterInfo::isPhysicalRegister(SrcReg) &&
++        (X86::GR8RegClass.contains(SrcReg) ||
++         X86::GR16RegClass.contains(SrcReg)))
++      return false;
++
++    return true;
++  }
++
+   double getExtraCost(const MachineInstr *MI,
+                       MachineRegisterInfo *MRI) const override {
+     assert(MI->getOpcode() == TargetOpcode::COPY && "Expected a COPY");
+diff --git a/test/CodeGen/X86/pr38803.ll b/test/CodeGen/X86/pr38803.ll
+new file mode 100644
+index 00000000000..a1ca27d89b0
+--- /dev/null
++++ b/test/CodeGen/X86/pr38803.ll
+@@ -0,0 +1,48 @@
++; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
++; RUN: llc < %s -mcpu=skylake-avx512 -mtriple=x86_64-unknown-unknown | FileCheck %s
++
++@b = local_unnamed_addr global i32 0, align 4
++@c = local_unnamed_addr global i32 0, align 4
++@d = local_unnamed_addr global float 0.000000e+00, align 4
++
++define float @_Z3fn2v() {
++; CHECK-LABEL: _Z3fn2v:
++; CHECK:       # %bb.0: # %entry
++; CHECK-NEXT:    pushq %rax
++; CHECK-NEXT:    .cfi_def_cfa_offset 16
++; CHECK-NEXT:    callq _Z1av
++; CHECK-NEXT:    # kill: def $al killed $al def $eax
++; CHECK-NEXT:    kmovd %eax, %k1
++; CHECK-NEXT:    vmovss {{.*#+}} xmm0 = mem[0],zero,zero,zero
++; CHECK-NEXT:    vmovss %xmm0, %xmm0, %xmm0 {%k1} {z}
++; CHECK-NEXT:    cmpl $0, {{.*}}(%rip)
++; CHECK-NEXT:    je .LBB0_2
++; CHECK-NEXT:  # %bb.1: # %if.then
++; CHECK-NEXT:    vcvtsi2ssl {{.*}}(%rip), %xmm1, %xmm1
++; CHECK-NEXT:    kmovd %eax, %k1
++; CHECK-NEXT:    vxorps %xmm2, %xmm2, %xmm2
++; CHECK-NEXT:    vmovss %xmm2, %xmm0, %xmm1 {%k1}
++; CHECK-NEXT:    vmovss %xmm1, {{.*}}(%rip)
++; CHECK-NEXT:  .LBB0_2: # %if.end
++; CHECK-NEXT:    popq %rax
++; CHECK-NEXT:    .cfi_def_cfa_offset 8
++; CHECK-NEXT:    retq
++entry:
++  %call = tail call zeroext i1 @_Z1av()
++  %cond = select i1 %call, float 7.500000e-01, float 0.000000e+00
++  %0 = load i32, i32* @c, align 4
++  %tobool2 = icmp eq i32 %0, 0
++  br i1 %tobool2, label %if.end, label %if.then
++
++if.then:                                          ; preds = %entry
++  %1 = load i32, i32* @b, align 4
++  %2 = sitofp i32 %1 to float
++  %conv5 = select i1 %call, float 0.000000e+00, float %2
++  store float %conv5, float* @d, align 4
++  br label %if.end
++
++if.end:                                           ; preds = %entry, %if.then
++  ret float %cond
++}
++
++declare zeroext i1 @_Z1av()
+-- 
+2.19.0
+
diff --git a/sys-devel/llvm/llvm-6.0.1-r2.ebuild b/sys-devel/llvm/llvm-6.0.1-r2.ebuild
new file mode 100644 (file)
index 0000000..d207897
--- /dev/null
@@ -0,0 +1,270 @@
+# Copyright 1999-2018 Gentoo Foundation
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=6
+
+: ${CMAKE_MAKEFILE_GENERATOR:=ninja}
+# (needed due to CMAKE_BUILD_TYPE != Gentoo)
+CMAKE_MIN_VERSION=3.7.0-r1
+PYTHON_COMPAT=( python2_7 )
+
+inherit cmake-utils eapi7-ver flag-o-matic multilib-minimal \
+       multiprocessing pax-utils python-any-r1 toolchain-funcs
+
+DESCRIPTION="Low Level Virtual Machine"
+HOMEPAGE="https://llvm.org/"
+SRC_URI="https://releases.llvm.org/${PV/_//}/${P/_/}.src.tar.xz
+       !doc? ( https://dev.gentoo.org/~mgorny/dist/llvm/${P}-manpages.tar.bz2 )"
+
+# Keep in sync with CMakeLists.txt
+ALL_LLVM_TARGETS=( AArch64 AMDGPU ARM BPF Hexagon Lanai Mips MSP430
+       NVPTX PowerPC Sparc SystemZ X86 XCore )
+ALL_LLVM_TARGETS=( "${ALL_LLVM_TARGETS[@]/#/llvm_targets_}" )
+
+# Additional licenses:
+# 1. OpenBSD regex: Henry Spencer's license ('rc' in Gentoo) + BSD.
+# 2. ARM backend: LLVM Software Grant by ARM.
+# 3. MD5 code: public-domain.
+# 4. Tests (not installed):
+#  a. gtest: BSD.
+#  b. YAML tests: MIT.
+
+LICENSE="UoI-NCSA rc BSD public-domain
+       llvm_targets_ARM? ( LLVM-Grant )"
+SLOT="$(ver_cut 1)"
+KEYWORDS="~amd64 ~arm ~arm64 ~ppc64 ~x86 ~amd64-fbsd ~amd64-linux ~ppc-macos ~x64-macos ~x86-macos"
+IUSE="debug doc gold libedit +libffi ncurses test xar xml
+       kernel_Darwin ${ALL_LLVM_TARGETS[*]}"
+RESTRICT="!test? ( test )"
+
+RDEPEND="
+       sys-libs/zlib:0=
+       gold? ( >=sys-devel/binutils-2.22:*[cxx] )
+       libedit? ( dev-libs/libedit:0=[${MULTILIB_USEDEP}] )
+       libffi? ( >=virtual/libffi-3.0.13-r1:0=[${MULTILIB_USEDEP}] )
+       ncurses? ( >=sys-libs/ncurses-5.9-r3:0=[${MULTILIB_USEDEP}] )
+       xar? ( app-arch/xar )
+       xml? ( dev-libs/libxml2:2=[${MULTILIB_USEDEP}] )"
+# configparser-3.2 breaks the build (3.3 or none at all are fine)
+DEPEND="${RDEPEND}
+       dev-lang/perl
+       || ( >=sys-devel/gcc-3.0 >=sys-devel/llvm-3.5
+               ( >=sys-freebsd/freebsd-lib-9.1-r10 sys-libs/libcxx )
+       )
+       kernel_Darwin? (
+               <sys-libs/libcxx-$(ver_cut 1-3).9999
+               >=sys-devel/binutils-apple-5.1
+       )
+       doc? ( dev-python/sphinx )
+       gold? ( sys-libs/binutils-libs )
+       libffi? ( virtual/pkgconfig )
+       !!<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="sys-devel/llvm-common
+       gold? ( >=sys-devel/llvmgold-${SLOT} )"
+
+REQUIRED_USE="${PYTHON_REQUIRED_USE}
+       || ( ${ALL_LLVM_TARGETS[*]} )"
+
+S=${WORKDIR}/${P/_/}.src
+
+# least intrusive of all
+CMAKE_BUILD_TYPE=RelWithDebInfo
+
+src_prepare() {
+       # Fix llvm-config for shared linking and sane flags
+       # https://bugs.gentoo.org/show_bug.cgi?id=565358
+       eapply "${FILESDIR}"/9999/0007-llvm-config-Clean-up-exported-values-update-for-shar.patch
+
+       # Fix appending -Wl,-rpath-link on non-Linux (-> FreeBSD).
+       eapply "${FILESDIR}"/6.0.1/0001-cmake-Append-Wl-rpath-link-conditionally-to-GNULD.patch
+
+       # Fix assembly compatibility with binutils-2.31.1
+       # https://bugs.gentoo.org/663442
+       eapply "${FILESDIR}"/6.0.1/0002-llvm-mc-Produce-R_X86_64_PLT32-for-call-jmp-foo.patch
+
+       # Fix x86 codegen bug triggered by Chromium
+       # https://bugs.gentoo.org/664868
+       eapply "${FILESDIR}"/7.0.0/0001-X86-Stop-X86DomainReassignment-from-creating-copies-.patch
+
+       # disable use of SDK on OSX, bug #568758
+       sed -i -e 's/xcrun/false/' utils/lit/lit/util.py || die
+
+       # User patches + QA
+       cmake-utils_src_prepare
+}
+
+multilib_src_configure() {
+       local ffi_cflags ffi_ldflags
+       if use libffi; then
+               ffi_cflags=$($(tc-getPKG_CONFIG) --cflags-only-I libffi)
+               ffi_ldflags=$($(tc-getPKG_CONFIG) --libs-only-L libffi)
+       fi
+
+       local libdir=$(get_libdir)
+       local mycmakeargs=(
+               # disable appending VCS revision to the version to improve
+               # direct cache hit ratio
+               -DLLVM_APPEND_VC_REV=OFF
+               -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_LIBXML2=$(usex xml)
+               -DLLVM_ENABLE_ASSERTIONS=$(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="${ffi_ldflags#-L}"
+               # used only for llvm-objdump tool
+               -DHAVE_LIBXAR=$(multilib_native_usex xar 1 0)
+
+               # 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+=(
+               -DLLVM_LIT_ARGS="-vv;-j;${LIT_JOBS:-$(makeopts_jobs "${MAKEOPTS}" "$(get_nproc)")}"
+       )
+
+       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+=(
+                       -DCMAKE_INSTALL_MANDIR="${EPREFIX}/usr/lib/llvm/${SLOT}/share/man"
+                       -DLLVM_INSTALL_SPHINX_HTML_DIR="${EPREFIX}/usr/share/doc/${PF}/html"
+                       -DSPHINX_WARNINGS_AS_ERRORS=OFF
+               )
+               use gold && mycmakeargs+=(
+                       -DLLVM_BINUTILS_INCDIR="${EPREFIX}"/usr/include
+               )
+       fi
+
+       if tc-is-cross-compiler; then
+               local tblgen="${EPREFIX}/usr/lib/llvm/${SLOT}/bin/llvm-tblgen"
+               [[ -x "${tblgen}" ]] \
+                       || die "${tblgen} not found or usable"
+               mycmakeargs+=(
+                       -DCMAKE_CROSSCOMPILING=ON
+                       -DLLVM_TABLEGEN="${tblgen}"
+               )
+       fi
+
+       # workaround BMI bug in gcc-7 (fixed in 7.4)
+       # https://bugs.gentoo.org/649880
+       # apply only to x86, https://bugs.gentoo.org/650506
+       if tc-is-gcc && [[ ${MULTILIB_ABI_FLAG} == abi_x86* ]] &&
+                       [[ $(gcc-major-version) -eq 7 && $(gcc-minor-version) -lt 4 ]]
+       then
+               local CFLAGS="${CFLAGS} -mno-bmi"
+               local CXXFLAGS="${CXXFLAGS} -mno-bmi"
+       fi
+
+       # LLVM_ENABLE_ASSERTIONS=NO does not guarantee this for us, #614844
+       use debug || local -x CPPFLAGS="${CPPFLAGS} -DNDEBUG"
+       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/${SLOT}/bin"
+               MANPATH="${EPREFIX}/usr/lib/llvm/${SLOT}/share/man"
+               LDPATH="$( IFS=:; echo "${LLVM_LDPATHS[*]}" )"
+_EOF_
+       doenvd "${T}/10llvm-${revord}"
+
+       # install pre-generated manpages
+       if ! use doc; then
+               # (doman does not support custom paths)
+               insinto "/usr/lib/llvm/${SLOT}/share/man/man1"
+               doins "${WORKDIR}/${P}-manpages/llvm"/*.1
+       fi
+
+       docompress "/usr/lib/llvm/${SLOT}/share/man"
+}
+
+pkg_postinst() {
+       elog "You can find additional opt-viewer utility scripts in:"
+       elog "  ${EROOT}/usr/lib/llvm/${SLOT}/share/opt-viewer"
+       elog "To use these scripts, you will need Python 2.7 along with the following"
+       elog "packages:"
+       elog "  dev-python/pygments (for opt-viewer)"
+       elog "  dev-python/pyyaml (for all of them)"
+}
diff --git a/sys-devel/llvm/llvm-7.0.0-r1.ebuild b/sys-devel/llvm/llvm-7.0.0-r1.ebuild
new file mode 100644 (file)
index 0000000..49fdc4c
--- /dev/null
@@ -0,0 +1,264 @@
+# Copyright 1999-2018 Gentoo Foundation
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=6
+
+: ${CMAKE_MAKEFILE_GENERATOR:=ninja}
+# (needed due to CMAKE_BUILD_TYPE != Gentoo)
+CMAKE_MIN_VERSION=3.7.0-r1
+PYTHON_COMPAT=( python2_7 )
+
+inherit cmake-utils eapi7-ver flag-o-matic multilib-minimal \
+       multiprocessing pax-utils python-any-r1 toolchain-funcs
+
+DESCRIPTION="Low Level Virtual Machine"
+HOMEPAGE="https://llvm.org/"
+SRC_URI="https://releases.llvm.org/${PV/_//}/${P/_/}.src.tar.xz
+       !doc? ( https://dev.gentoo.org/~mgorny/dist/llvm/${P}-manpages.tar.bz2 )"
+
+# Keep in sync with CMakeLists.txt
+ALL_LLVM_TARGETS=( AArch64 AMDGPU ARM BPF Hexagon Lanai Mips MSP430
+       NVPTX PowerPC Sparc SystemZ X86 XCore )
+ALL_LLVM_TARGETS=( "${ALL_LLVM_TARGETS[@]/#/llvm_targets_}" )
+
+# Additional licenses:
+# 1. OpenBSD regex: Henry Spencer's license ('rc' in Gentoo) + BSD.
+# 2. ARM backend: LLVM Software Grant by ARM.
+# 3. MD5 code: public-domain.
+# 4. Tests (not installed):
+#  a. gtest: BSD.
+#  b. YAML tests: MIT.
+
+LICENSE="UoI-NCSA rc BSD public-domain
+       llvm_targets_ARM? ( LLVM-Grant )"
+SLOT="$(ver_cut 1)"
+KEYWORDS="~amd64 ~arm ~arm64 ~ppc64 ~x86 ~amd64-fbsd ~amd64-linux ~ppc-macos ~x64-macos ~x86-macos"
+IUSE="debug doc exegesis gold libedit +libffi ncurses test xar xml
+       kernel_Darwin ${ALL_LLVM_TARGETS[*]}"
+RESTRICT="!test? ( test )"
+
+RDEPEND="
+       sys-libs/zlib:0=
+       exegesis? ( dev-libs/libpfm:= )
+       gold? ( >=sys-devel/binutils-2.22:*[cxx] )
+       libedit? ( dev-libs/libedit:0=[${MULTILIB_USEDEP}] )
+       libffi? ( >=virtual/libffi-3.0.13-r1:0=[${MULTILIB_USEDEP}] )
+       ncurses? ( >=sys-libs/ncurses-5.9-r3:0=[${MULTILIB_USEDEP}] )
+       xar? ( app-arch/xar )
+       xml? ( dev-libs/libxml2:2=[${MULTILIB_USEDEP}] )"
+# configparser-3.2 breaks the build (3.3 or none at all are fine)
+DEPEND="${RDEPEND}
+       dev-lang/perl
+       || ( >=sys-devel/gcc-3.0 >=sys-devel/llvm-3.5
+               ( >=sys-freebsd/freebsd-lib-9.1-r10 sys-libs/libcxx )
+       )
+       kernel_Darwin? (
+               <sys-libs/libcxx-$(ver_cut 1-3).9999
+               >=sys-devel/binutils-apple-5.1
+       )
+       doc? ( dev-python/sphinx )
+       gold? ( sys-libs/binutils-libs )
+       libffi? ( virtual/pkgconfig )
+       !!<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="sys-devel/llvm-common
+       gold? ( >=sys-devel/llvmgold-${SLOT} )"
+
+REQUIRED_USE="${PYTHON_REQUIRED_USE}
+       || ( ${ALL_LLVM_TARGETS[*]} )"
+
+S=${WORKDIR}/${P/_/}.src
+
+# least intrusive of all
+CMAKE_BUILD_TYPE=RelWithDebInfo
+
+src_prepare() {
+       # Fix llvm-config for shared linking and sane flags
+       # https://bugs.gentoo.org/show_bug.cgi?id=565358
+       eapply "${FILESDIR}"/9999/0007-llvm-config-Clean-up-exported-values-update-for-shar.patch
+
+       # Fix x86 codegen bug triggered by Chromium
+       # https://bugs.gentoo.org/664868
+       eapply "${FILESDIR}"/7.0.0/0001-X86-Stop-X86DomainReassignment-from-creating-copies-.patch
+
+       # disable use of SDK on OSX, bug #568758
+       sed -i -e 's/xcrun/false/' utils/lit/lit/util.py || die
+
+       # User patches + QA
+       cmake-utils_src_prepare
+}
+
+multilib_src_configure() {
+       local ffi_cflags ffi_ldflags
+       if use libffi; then
+               ffi_cflags=$($(tc-getPKG_CONFIG) --cflags-only-I libffi)
+               ffi_ldflags=$($(tc-getPKG_CONFIG) --libs-only-L libffi)
+       fi
+
+       local libdir=$(get_libdir)
+       local mycmakeargs=(
+               # disable appending VCS revision to the version to improve
+               # direct cache hit ratio
+               -DLLVM_APPEND_VC_REV=OFF
+               -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_LIBXML2=$(usex xml)
+               -DLLVM_ENABLE_ASSERTIONS=$(usex debug)
+               -DLLVM_ENABLE_LIBPFM=$(usex exegesis)
+               -DLLVM_ENABLE_EH=ON
+               -DLLVM_ENABLE_RTTI=ON
+
+               -DWITH_POLLY=OFF # TODO
+
+               -DLLVM_HOST_TRIPLE="${CHOST}"
+
+               -DFFI_INCLUDE_DIR="${ffi_cflags#-I}"
+               -DFFI_LIBRARY_DIR="${ffi_ldflags#-L}"
+               # used only for llvm-objdump tool
+               -DHAVE_LIBXAR=$(multilib_native_usex xar 1 0)
+
+               # disable OCaml bindings (now in dev-ml/llvm-ocaml)
+               -DOCAMLFIND=NO
+       )
+
+#      Note: go bindings have no CMake rules at the moment
+#      but let's kill the check in case they are introduced
+#      if ! multilib_is_native_abi || ! use go; then
+               mycmakeargs+=(
+                       -DGO_EXECUTABLE=GO_EXECUTABLE-NOTFOUND
+               )
+#      fi
+
+       use test && mycmakeargs+=(
+               -DLLVM_LIT_ARGS="-vv;-j;${LIT_JOBS:-$(makeopts_jobs "${MAKEOPTS}" "$(get_nproc)")}"
+       )
+
+       if multilib_is_native_abi; then
+               mycmakeargs+=(
+                       -DLLVM_BUILD_DOCS=$(usex doc)
+                       -DLLVM_ENABLE_OCAMLDOC=OFF
+                       -DLLVM_ENABLE_SPHINX=$(usex doc)
+                       -DLLVM_ENABLE_DOXYGEN=OFF
+                       -DLLVM_INSTALL_UTILS=ON
+               )
+               use doc && mycmakeargs+=(
+                       -DCMAKE_INSTALL_MANDIR="${EPREFIX}/usr/lib/llvm/${SLOT}/share/man"
+                       -DLLVM_INSTALL_SPHINX_HTML_DIR="${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
+               local tblgen="${EPREFIX}/usr/lib/llvm/${SLOT}/bin/llvm-tblgen"
+               [[ -x "${tblgen}" ]] \
+                       || die "${tblgen} not found or usable"
+               mycmakeargs+=(
+                       -DCMAKE_CROSSCOMPILING=ON
+                       -DLLVM_TABLEGEN="${tblgen}"
+               )
+       fi
+
+       # workaround BMI bug in gcc-7 (fixed in 7.4)
+       # https://bugs.gentoo.org/649880
+       # apply only to x86, https://bugs.gentoo.org/650506
+       if tc-is-gcc && [[ ${MULTILIB_ABI_FLAG} == abi_x86* ]] &&
+                       [[ $(gcc-major-version) -eq 7 && $(gcc-minor-version) -lt 4 ]]
+       then
+               local CFLAGS="${CFLAGS} -mno-bmi"
+               local CXXFLAGS="${CXXFLAGS} -mno-bmi"
+       fi
+
+       # LLVM_ENABLE_ASSERTIONS=NO does not guarantee this for us, #614844
+       use debug || local -x CPPFLAGS="${CPPFLAGS} -DNDEBUG"
+       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 - ${SLOT} ))
+       newenvd - "10llvm-${revord}" <<-_EOF_
+               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"
+               MANPATH="${EPREFIX}/usr/lib/llvm/${SLOT}/share/man"
+               LDPATH="$( IFS=:; echo "${LLVM_LDPATHS[*]}" )"
+       _EOF_
+
+       # install pre-generated manpages
+       if ! use doc; then
+               # (doman does not support custom paths)
+               insinto "/usr/lib/llvm/${SLOT}/share/man/man1"
+               doins "${WORKDIR}/${P}-manpages/llvm"/*.1
+       fi
+
+       docompress "/usr/lib/llvm/${SLOT}/share/man"
+}
+
+pkg_postinst() {
+       elog "You can find additional opt-viewer utility scripts in:"
+       elog "  ${EROOT%/}/usr/lib/llvm/${SLOT}/share/opt-viewer"
+       elog "To use these scripts, you will need Python 2.7 along with the following"
+       elog "packages:"
+       elog "  dev-python/pygments (for opt-viewer)"
+       elog "  dev-python/pyyaml (for all of them)"
+}