configure_llvm.sh does not install chipStar's fork of LLVM

[linehill]

The README suggests that the configure_llvm.sh script installs the chipStar's fork of the LLVM but that does not seem to be the case. See the following invocation:

$ bash -x ./configure_llvm.sh 17 foobar dynamic on
Command: 'bash -x ./configure_llvm.sh 17 foobar dynamic on'
+ set -e
+ '[' 4 -ne 4 ']'
+ '[' 17 '!=' 15 ']'
+ '[' 17 '!=' 16 ']'
+ '[' 17 '!=' 17 ']'
+ '[' dynamic '!=' static ']'
+ '[' dynamic '!=' dynamic ']'
+ '[' on '!=' on ']'
+ VERSION=17
+ INSTALL_DIR=foobar
+ LINK_TYPE=dynamic
+ '[' on == on ']'
+ LLVM_BRANCH=spirv-ext-fixes-17
+ TRANSLATOR_BRANCH=llvm_release_170
++ pwd
+ export LLVM_DIR=/mnt/md0/linehill/ws-chip-spv-3/chipstar/scripts/llvm-project/llvm
+ LLVM_DIR=/mnt/md0/linehill/ws-chip-spv-3/chipstar/scripts/llvm-project/llvm
+ LLVM_BRANCH=release/17.x
+ SPIRV_BRANCH=llvm_release_170
+ '[' '!' -d llvm-project ']'
+ git clone https://github.com/llvm/llvm-project.git -b release/17.x --depth 1
Cloning into 'llvm-project'...
^C

Couple things are not right:

• The script is cloning the upstream repository instead of chipStar's fork.
• The script does not checkout the branch which has the chipStar's patches.

Also, the LLVM_BRANCH=spirv-ext-fixes-17 assignment gets overwritten.