flang/tools/flang-driver/fc1_main.cpp

   1 //===-- fc1_main.cpp - Flang FC1 Compiler Frontend ------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This is the entry point to the flang -fc1 functionality, which implements the
  10 // core compiler functionality along with a number of additional tools for
  11 // demonstration and testing purposes.
  12 //
  13 //===----------------------------------------------------------------------===//
  14 //
  15 // Coding style: https://mlir.llvm.org/getting_started/DeveloperGuide/
  16 //
  17 //===----------------------------------------------------------------------===//
  18
  19 #include "flang/Frontend/CompilerInstance.h"
  20 #include "flang/Frontend/CompilerInvocation.h"
  21 #include "flang/Frontend/TextDiagnosticBuffer.h"
  22 #include "flang/FrontendTool/Utils.h"
  23 #include "clang/Driver/DriverDiagnostic.h"
  24 #include "llvm/MC/TargetRegistry.h"
  25 #include "llvm/Option/Arg.h"
  26 #include "llvm/Option/ArgList.h"
  27 #include "llvm/Option/OptTable.h"
  28 #include "llvm/Support/TargetSelect.h"
  29 #include "llvm/Support/raw_ostream.h"
  30
  31 #include <cstdio>
  32
  33 using namespace Fortran::frontend;
  34
  35 /// Print supported cpus of the given target.
  36 static int printSupportedCPUs(llvm::StringRef triple) {
  37   std::string error;
  38   const llvm::Target *target =
  39       llvm::TargetRegistry::lookupTarget(triple, error);
  40   if (!target) {
  41     llvm::errs() << error;
  42     return 1;
  43   }
  44
  45   // the target machine will handle the mcpu printing
  46   llvm::TargetOptions targetOpts;
  47   std::unique_ptr<llvm::TargetMachine> targetMachine(
  48       target->createTargetMachine(triple, "", "+cpuhelp", targetOpts,
  49                                   std::nullopt));
  50   return 0;
  51 }
  52
  53 int fc1_main(llvm::ArrayRef<const char *> argv, const char *argv0) {
  54   // Create CompilerInstance
  55   std::unique_ptr<CompilerInstance> flang(new CompilerInstance());
  56
  57   // Create DiagnosticsEngine for the frontend driver
  58   flang->createDiagnostics();
  59   if (!flang->hasDiagnostics())
  60     return 1;
  61
  62   // We will buffer diagnostics from argument parsing so that we can output
  63   // them using a well formed diagnostic object.
  64   TextDiagnosticBuffer *diagsBuffer = new TextDiagnosticBuffer;
  65
  66   // Create CompilerInvocation - use a dedicated instance of DiagnosticsEngine
  67   // for parsing the arguments
  68   llvm::IntrusiveRefCntPtr<clang::DiagnosticIDs> diagID(
  69       new clang::DiagnosticIDs());
  70   llvm::IntrusiveRefCntPtr<clang::DiagnosticOptions> diagOpts =
  71       new clang::DiagnosticOptions();
  72   clang::DiagnosticsEngine diags(diagID, &*diagOpts, diagsBuffer);
  73   bool success = CompilerInvocation::createFromArgs(flang->getInvocation(),
  74                                                     argv, diags, argv0);
  75
  76   // Initialize targets first, so that --version shows registered targets.
  77   llvm::InitializeAllTargets();
  78   llvm::InitializeAllTargetMCs();
  79   llvm::InitializeAllAsmPrinters();
  80
  81   // --print-supported-cpus takes priority over the actual compilation.
  82   if (flang->getFrontendOpts().printSupportedCPUs)
  83     return printSupportedCPUs(flang->getInvocation().getTargetOpts().triple);
  84
  85   diagsBuffer->flushDiagnostics(flang->getDiagnostics());
  86
  87   if (!success)
  88     return 1;
  89
  90   // Execute the frontend actions.
  91   success = executeCompilerInvocation(flang.get());
  92
  93   // Delete output files to free Compiler Instance
  94   flang->clearOutputFiles(/*EraseFiles=*/false);
  95
  96   return !success;
  97 }