require 'package'

class Llvm_stage1 < Package
  description 'THIS IS NOT THE LLVM PACKAGE. This is only a Limited Stage 1 compile of LLVM.'
  homepage 'https://llvm.org/'
  version '13.0.0'
  license 'Apache-2.0-with-LLVM-exceptions, UoI-NCSA, BSD, public-domain and rc'
  compatibility 'all'
  source_url "https://github.com/llvm/llvm-project/releases/download/llvmorg-#{version}/llvm-project-#{version}.src.tar.xz"
  source_sha256 '6075ad30f1ac0e15f07c1bf062c1e1268c241d674f11bd32cdf0e040c71f2bf3'
  binary_compression 'tpxz'

  binary_sha256({
    aarch64: '471ccebb72765a304bc8a1097e144b16d33e1fbbef5dd27fa4ed43530aaf2ee8',
     armv7l: '471ccebb72765a304bc8a1097e144b16d33e1fbbef5dd27fa4ed43530aaf2ee8',
       i686: '02bd963269fc8fb491bb641f8eb6acd00ed543ccdfe2707cb540d6b792961b44',
     x86_64: '310143770e287975bcb97e454d7e63f3f74ebaca5e02ea88d5f2e1140d0d3ac7'
  })

  # llvm_stage1 is compiled with gcc, without -flto
  # Then in stage 2 (llvm.rb) everything is compiled with clang built in stage 1, with -flto=thin
  # FYI LLVM 11.1.0 is a tiny rebuild of 11.0.1 fixing ABI compatibility with LLVM 10.0.0 & LLVM 12

  depends_on 'ocaml' => :build
  depends_on 'libedit'
  depends_on 'libtirpc'
  depends_on 'swig'
  depends_on 'py3_pygments' => :build
  # depends_on 'ccache' => :build

  case ARCH
  when 'aarch64', 'armv7l'
    # LLVM_TARGETS_TO_BUILD = 'ARM;AArch64;AMDGPU'
    @ARCH_C_FLAGS = '-march=armv7-a -mfloat-abi=hard'
    @ARCH_CXX_FLAGS = '-march=armv7-a -mfloat-abi=hard'
    LLVM_PROJECTS_TO_BUILD = 'clang;clang-tools-extra;libcxx;libcxxabi;lld'.freeze
  when 'i686', 'x86_64'
    # LLVM_TARGETS_TO_BUILD = 'X86;AMDGPU'
    @ARCH_C_FLAGS = '-fPIC'
    @ARCH_CXX_FLAGS = '-fPIC'
    LLVM_PROJECTS_TO_BUILD = 'clang;clang-tools-extra;libcxx;libcxxabi;libunwind;lld'.freeze
  end

  @ARCH_C_LTO_FLAGS = "#{@ARCH_C_FLAGS} -flto"
  @ARCH_CXX_LTO_FLAGS = "#{@ARCH_CXX_FLAGS} -flto"

  # Using Targets 'all' because otherwise mesa complains.
  # This may be patched upstream as per
  # https://reviews.llvm.org/rG1de56d6d13c083c996dfd44a32041dacae037d66
  LLVM_TARGETS_TO_BUILD = 'all'.freeze
  LLVM_VERSION = version.split('-')[0]

  def self.build
    ############################################################
    puts "Building LLVM Targets: #{LLVM_TARGETS_TO_BUILD}".lightgreen
    puts "Building LLVM Projects: #{LLVM_PROJECTS_TO_BUILD}".lightgreen
    ############################################################
    ############################################################
    puts 'Setting compile to use python3'.lightgreen
    ############################################################
    system "grep -rl '#!.*python' | xargs sed -i '1s/python$/python3/'"

    Dir.mkdir 'builddir'
    Dir.chdir 'builddir' do
      system "echo '#!/bin/bash
machine=\$(gcc -dumpmachine)
version=\$(gcc -dumpversion)
gnuc_lib=#{CREW_LIB_PREFIX}/gcc/\${machine}/\${version}
clang -B \${gnuc_lib} -L \${gnuc_lib} \"\$@\"' > clc"
      system "echo '#!/bin/bash
machine=\$(gcc -dumpmachine)
version=\$(gcc -dumpversion)
cxx_sys=#{CREW_PREFIX}/include/c++/\${version}
cxx_inc=#{CREW_PREFIX}/include/c++/\${version}/\${machine}
gnuc_lib=#{CREW_LIB_PREFIX}/gcc/\${machine}/\${version}
clang++ -fPIC  -rtlib=compiler-rt -stdlib=libc++ -cxx-isystem \${cxx_sys} -I \${cxx_inc} -B \${gnuc_lib} -L \${gnuc_lib} \"\$@\"' > clc++"
      system "env PATH=#{CREW_LIB_PREFIX}/ccache/bin:#{CREW_PREFIX}/bin:/usr/bin:/bin FC= \
            cmake -G Ninja \
            -DCMAKE_INSTALL_PREFIX=#{CREW_PREFIX} \
            -DLLVM_DEFAULT_TARGET_TRIPLE=#{CREW_TARGET} \
            -DLLVM_TARGETS_TO_BUILD=\'#{LLVM_TARGETS_TO_BUILD}' \
            -DCMAKE_BUILD_TYPE=Release \
            -DLLVM_LIBDIR_SUFFIX='#{CREW_LIB_SUFFIX}' \
            -DCMAKE_LINKER=$(which ld.gold) \
            -D_CMAKE_TOOLCHAIN_PREFIX=gcc- \
            -DLLVM_BUILD_LLVM_DYLIB=ON \
            -DLLVM_LINK_LLVM_DYLIB=ON \
            -DLLVM_ENABLE_FFI=ON \
            -DLLVM_ENABLE_RTTI=ON \
            -DCMAKE_C_FLAGS='#{@ARCH_C_FLAGS}' \
            -DCMAKE_CXX_FLAGS='#{@ARCH_CXX_FLAGS}' \
            -DPYTHON_EXECUTABLE=$(which python3) \
            -DLLVM_BINUTILS_INCDIR='#{CREW_PREFIX}/include' \
            -DLLVM_OPTIMIZED_TABLEGEN=ON \
            -DLLVM_ENABLE_TERMINFO=ON \
            -DLLVM_ENABLE_PROJECTS='#{LLVM_PROJECTS_TO_BUILD}' \
            -DLIBUNWIND_C_FLAGS='-fno-exceptions -funwind-tables' \
            -DLIBUNWIND_CXX_FLAGS='-fno-exceptions -funwind-tables' \
            -DLIBUNWIND_SUPPORTS_FUNWIND_TABLES_FLAG=ON \
            -DLIBUNWIND_SUPPORTS_FNO_EXCEPTIONS_FLAG=ON \
            -DCOMPILER_RT_BUILD_SANITIZERS=OFF \
            -DCOMPILER_RT_BUILD_LIBFUZZER=OFF \
            -DCOMPILER_RT_BUILD_BUILTINS=ON \
            -DCOMPILER_RT_DEFAULT_TARGET_ONLY=ON \
            -Wno-dev \
            ../llvm"
      system 'ninja'
    end
  end

  def self.install
    Dir.chdir('builddir') do
      system "DESTDIR=#{CREW_DEST_DIR} ninja install"
      FileUtils.mkdir_p "#{CREW_DEST_LIB_PREFIX}/bfd-plugins"
      FileUtils.ln_s "lib#{CREW_LIB_SUFFIX}/LLVMgold.so", "#{CREW_DEST_LIB_PREFIX}/bfd-plugins/"
    end
  end

  def self.check
    Dir.chdir('builddir') do
      # system "ninja check-llvm || true"
      # system "ninja check-clang || true"
      # system "ninja check-lld || true"
    end
  end

  def self.postinstall
    puts
    puts "To compile programs, use 'clang' or 'clang++'.".lightblue
    puts
  end
end