Split the building of the toolchain into individual shellscripts

This simplifies building the toolchain outside of docker.

build-llvm.sh

@@ -0,0 +1,48 @@
+#!/bin/sh
+
+set -e
+
+if [ $# -lt 1 ]; then
+    echo $0 dest
+    exit 1
+fi
+PREFIX="$1"
+
+: ${CORES:=4}
+
+if [ ! -d llvm ]; then
+    # When cloning master and checking out a pinned old hash, we can't use --depth=1.
+    # Do the git-svn rebase to populate git-svn information, to make
+    # "clang --version" produce SVN based version numbers.
+    git clone -b master https://github.com/llvm-mirror/llvm.git
+    cd llvm/tools
+    git clone -b master https://github.com/llvm-mirror/clang.git
+    git clone -b master https://github.com/llvm-mirror/lld.git
+    cd ..
+    git svn init https://llvm.org/svn/llvm-project/llvm/trunk
+    git config svn-remote.svn.fetch :refs/remotes/origin/master
+    git svn rebase -l
+    git checkout c8f103e52b297f3e3e0ed1756e11373c68af3566
+    cd tools/clang
+    git svn init https://llvm.org/svn/llvm-project/cfe/trunk
+    git config svn-remote.svn.fetch :refs/remotes/origin/master
+    git svn rebase -l
+    git checkout fdd60aee9c0ea40fa0423d6e43821f53d07961d5
+    cd ../lld
+    git svn init https://llvm.org/svn/llvm-project/lld/trunk
+    git config svn-remote.svn.fetch :refs/remotes/origin/master
+    git svn rebase -l
+    git checkout f4208caae12f685c06657aa6e2b9b1eda4adcdb4
+    cd ../../..
+fi
+
+cd llvm
+mkdir -p build
+cd build
+cmake \
+    -DCMAKE_INSTALL_PREFIX="$PREFIX" \
+    -DCMAKE_BUILD_TYPE=Release \
+    -DLLVM_ENABLE_ASSERTIONS=ON \
+    -DLLVM_TARGETS_TO_BUILD="ARM;AArch64;X86" \
+    ..
+make -j$CORES install