//===-- Flang.cpp - Flang+LLVM ToolChain Implementations --------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//


#include "Flang.h"
#include "CommonArgs.h"

#include "clang/Driver/Options.h"

#include <cassert>

using namespace clang::driver;
using namespace clang::driver::tools;
using namespace clang;
using namespace llvm::opt;

void Flang::ConstructJob(Compilation &C, const JobAction &JA,
                         const InputInfo &Output, const InputInfoList &Inputs,
                         const ArgList &Args, const char *LinkingOutput) const {
  const auto &TC = getToolChain();
  const llvm::Triple &Triple = TC.getEffectiveTriple();
  const std::string &TripleStr = Triple.getTriple();

  ArgStringList CmdArgs;

  CmdArgs.push_back("-fc1");

  // TODO: Eventually all actions will require a triple (e.g. `-triple
  // aarch64-unknown-linux-gnu`). However, `-triple` is currently not supported
  // by `flang-new -fc1`, so we only add it selectively to actions that we
  // don't support/execute just yet.
  if (isa<PreprocessJobAction>(JA)) {
    if (C.getArgs().hasArg(options::OPT_test_io))
      CmdArgs.push_back("-test-io");
    else
      CmdArgs.push_back("-E");
  } else if (isa<CompileJobAction>(JA) || isa<BackendJobAction>(JA)) {
    CmdArgs.push_back("-triple");
    CmdArgs.push_back(Args.MakeArgString(TripleStr));
    if (JA.getType() == types::TY_Nothing) {
      CmdArgs.push_back("-fsyntax-only");
    } else if (JA.getType() == types::TY_AST) {
      CmdArgs.push_back("-emit-ast");
    } else if (JA.getType() == types::TY_LLVM_IR ||
               JA.getType() == types::TY_LTO_IR) {
      CmdArgs.push_back("-emit-llvm");
    } else if (JA.getType() == types::TY_LLVM_BC ||
               JA.getType() == types::TY_LTO_BC) {
      CmdArgs.push_back("-emit-llvm-bc");
    } else if (JA.getType() == types::TY_PP_Asm) {
      CmdArgs.push_back("-S");
    } else {
      assert(false && "Unexpected output type!");
    }
  } else if (isa<AssembleJobAction>(JA)) {
    CmdArgs.push_back("-triple");
    CmdArgs.push_back(Args.MakeArgString(TripleStr));
    CmdArgs.push_back("-emit-obj");
  } else {
    assert(false && "Unexpected action class for Flang tool.");
  }

  if (Output.isFilename()) {
    CmdArgs.push_back("-o");
    CmdArgs.push_back(Output.getFilename());
  } else {
    assert(Output.isNothing() && "Invalid output.");
  }

  const InputInfo &Input = Inputs[0];
  assert(Input.isFilename() && "Invalid input.");
  CmdArgs.push_back(Input.getFilename());

  const auto& D = C.getDriver();
  // TODO: Replace flang-new with flang once the new driver replaces the
  // throwaway driver
  const char *Exec = Args.MakeArgString(D.GetProgramPath("flang-new", TC));
  C.addCommand(std::make_unique<Command>(JA, *this,
                                         ResponseFileSupport::AtFileUTF8(),
                                         Exec, CmdArgs, Inputs, Output));
}

Flang::Flang(const ToolChain &TC) : Tool("flang-new", "flang frontend", TC) {}

Flang::~Flang() {}