Use LLVM fork with hardening patches

Author: luismarques

build-clang-with-args.sh

@@ -57,7 +57,7 @@ cd "${build_top_dir}/build"
 
 llvm_dir="${build_top_dir}/build/llvm-project"
 if [ ! -d "${llvm_dir}" ]; then
-  git clone ${LLVM_URL} "${llvm_dir}"
+  git clone --branch ${LLVM_BRANCH} ${LLVM_URL} "${llvm_dir}"
 fi
 cd "${llvm_dir}"
 git fetch origin

sw-versions.sh

@@ -9,6 +9,7 @@ export CROSSTOOL_NG_VERSION=5075e1f98e4329502682746cc30fa5c0c5a19d26
 # v4.0.1
 export QEMU_VERSION=23967e5b2a6c6d04b8db766a8a149f3631a7b899
 
-# LLVM 13.0.1 (tag llvmorg-13.0.1)
-export LLVM_URL=https://github.com/llvm/llvm-project.git
-export LLVM_VERSION=75e33f71c2dae584b13a7d1186ae0a038ba98838
+# LLVM 13.0.1 plus hardening patches
+export LLVM_URL=https://github.com/lowRISC/llvm-project.git
+export LLVM_BRANCH=ot-hardening
+export LLVM_VERSION=20a7c03bfa587068b70cf7d8f7eb38fa04d30cd5