tools/llvm-as/llvm-as.cpp

   1 //===--- llvm-as.cpp - The low-level LLVM assembler -----------------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 //  This utility may be invoked in the following manner:
  11 //   llvm-as --help         - Output information about command line switches
  12 //   llvm-as [options]      - Read LLVM asm from stdin, write bitcode to stdout
  13 //   llvm-as [options] x.ll - Read LLVM asm from the x.ll file, write bitcode
  14 //                            to the x.bc file.
  15 //
  16 //===----------------------------------------------------------------------===//
  17
  18 #include "llvm/LLVMContext.h"
  19 #include "llvm/Module.h"
  20 #include "llvm/Assembly/Parser.h"
  21 #include "llvm/Analysis/Verifier.h"
  22 #include "llvm/Bitcode/ReaderWriter.h"
  23 #include "llvm/Support/CommandLine.h"
  24 #include "llvm/Support/ManagedStatic.h"
  25 #include "llvm/Support/PrettyStackTrace.h"
  26 #include "llvm/Support/SourceMgr.h"
  27 #include "llvm/Support/SystemUtils.h"
  28 #include "llvm/Support/raw_ostream.h"
  29 #include "llvm/System/Signals.h"
  30 #include <memory>
  31 using namespace llvm;
  32
  33 static cl::opt<std::string>
  34 InputFilename(cl::Positional, cl::desc("<input .llvm file>"), cl::init("-"));
  35
  36 static cl::opt<std::string>
  37 OutputFilename("o", cl::desc("Override output filename"),
  38                cl::value_desc("filename"));
  39
  40 static cl::opt<bool>
  41 Force("f", cl::desc("Enable binary output on terminals"));
  42
  43 static cl::opt<bool>
  44 DisableOutput("disable-output", cl::desc("Disable output"), cl::init(false));
  45
  46 static cl::opt<bool>
  47 DumpAsm("d", cl::desc("Print assembly as parsed"), cl::Hidden);
  48
  49 static cl::opt<bool>
  50 DisableVerify("disable-verify", cl::Hidden,
  51               cl::desc("Do not run verifier on input LLVM (dangerous!)"));
  52
  53 static void WriteOutputFile(const Module *M) {
  54   // Infer the output filename if needed.
  55   if (OutputFilename.empty()) {
  56     if (InputFilename == "-") {
  57       OutputFilename = "-";
  58     } else {
  59       std::string IFN = InputFilename;
  60       int Len = IFN.length();
  61       if (IFN[Len-3] == '.' && IFN[Len-2] == 'l' && IFN[Len-1] == 'l') {
  62         // Source ends in .ll
  63         OutputFilename = std::string(IFN.begin(), IFN.end()-3);
  64       } else {
  65         OutputFilename = IFN;   // Append a .bc to it
  66       }
  67       OutputFilename += ".bc";
  68     }
  69   }
  70
  71   // Make sure that the Out file gets unlinked from the disk if we get a
  72   // SIGINT.
  73   if (OutputFilename != "-")
  74     sys::RemoveFileOnSignal(sys::Path(OutputFilename));
  75
  76   std::string ErrorInfo;
  77   std::auto_ptr<raw_ostream> Out
  78   (new raw_fd_ostream(OutputFilename.c_str(), ErrorInfo,
  79                       raw_fd_ostream::F_Binary));
  80   if (!ErrorInfo.empty()) {
  81     errs() << ErrorInfo << '\n';
  82     exit(1);
  83   }
  84
  85   if (Force || !CheckBitcodeOutputToConsole(*Out, true))
  86     WriteBitcodeToFile(M, *Out);
  87 }
  88
  89 int main(int argc, char **argv) {
  90   // Print a stack trace if we signal out.
  91   sys::PrintStackTraceOnErrorSignal();
  92   PrettyStackTraceProgram X(argc, argv);
  93   LLVMContext &Context = getGlobalContext();
  94   llvm_shutdown_obj Y;  // Call llvm_shutdown() on exit.
  95   cl::ParseCommandLineOptions(argc, argv, "llvm .ll -> .bc assembler\n");
  96
  97   // Parse the file now...
  98   SMDiagnostic Err;
  99   std::auto_ptr<Module> M(ParseAssemblyFile(InputFilename, Err, Context));
 100   if (M.get() == 0) {
 101     Err.Print(argv[0], errs());
 102     return 1;
 103   }
 104
 105   if (!DisableVerify) {
 106     std::string Err;
 107     if (verifyModule(*M.get(), ReturnStatusAction, &Err)) {
 108       errs() << argv[0]
 109              << ": assembly parsed, but does not verify as correct!\n";
 110       errs() << Err;
 111       return 1;
 112     }
 113   }
 114
 115   if (DumpAsm) errs() << "Here's the assembly:\n" << *M.get();
 116
 117   if (!DisableOutput)
 118     WriteOutputFile(M.get());
 119
 120   return 0;
 121 }