Support LLVM backend #529

	name: CI

	on:
	push:
	branches:
	- main
	pull_request:
	branches:
	- main

	jobs:
	format:
	runs-on: ubuntu-22.04
	steps:
	- uses: actions/checkout@v3
	- name: coding convention
	run: \|
	sudo apt-get install -q -y clang-format
	scripts/check-format.sh

	tidy:
	runs-on: ubuntu-22.04
	steps:
	- uses: actions/checkout@v3
	with:
	# Fetch all history for proper diffing.
	fetch-depth: 0
	- name: Install cxxopts
	run: scripts/install-cxxopts.sh
	- name: Install fmt
	run: scripts/install-fmt.sh
	- name: Install bear
	run: sudo apt-get install -q -y bear
	- name: Install clang-tidy
	run: \|
	sudo add-apt-repository -y 'deb http://apt.llvm.org/jammy/ llvm-toolchain-jammy-18 main'
	wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key \| sudo apt-key add -
	sudo apt-get update
	sudo apt-get install -q -y clang-tidy-18
	- name: static checks
	run: \|
	export CLANG_TIDY=clang-tidy-18
	make tidy

	test:
	runs-on: ubuntu-22.04
	strategy:
	matrix:
	cxx: [g++, clang++]
	steps:
	- uses: actions/checkout@v3
	- uses: actions/setup-python@v3
	- name: Install LLVM
	run: \|
	sudo add-apt-repository -y 'deb http://apt.llvm.org/jammy/ llvm-toolchain-jammy-18 main'
	wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key \| sudo apt-key add -
	sudo apt-get update
	sudo apt-get install -q -y llvm-18 lld-18 llvm-18-runtime
	- name: Install QBE
	run: scripts/install-qbe.sh
	- name: Install cxxopts
	run: scripts/install-cxxopts.sh
	- name: Install fmt
	run: scripts/install-fmt.sh
	- name: Install Turnt
	run: pip install turnt
	- name: Run tests
	run: make test CXX=${{ matrix.cxx }}

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