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/Module.h"
  19 #include "llvm/Assembly/Parser.h"
  20 #include "llvm/Analysis/Verifier.h"
  21 #include "llvm/Bitcode/ReaderWriter.h"
  22 #include "llvm/Support/CommandLine.h"
  23 #include "llvm/Support/ManagedStatic.h"
  24 #include "llvm/Support/PrettyStackTrace.h"
  25 #include "llvm/Support/Streams.h"
  26 #include "llvm/Support/SystemUtils.h"
  27 #include "llvm/Support/raw_ostream.h"
  28 #include "llvm/System/Signals.h"
  29 #include <fstream>
  30 #include <iostream>
  31 #include <memory>
  32 using namespace llvm;
  33
  34 static cl::opt<std::string>
  35 InputFilename(cl::Positional, cl::desc("<input .llvm file>"), cl::init("-"));
  36
  37 static cl::opt<std::string>
  38 OutputFilename("o", cl::desc("Override output filename"),
  39                cl::value_desc("filename"));
  40
  41 static cl::opt<bool>
  42 Force("f", cl::desc("Overwrite output files"));
  43
  44 static cl::opt<bool>
  45 DisableOutput("disable-output", cl::desc("Disable output"), cl::init(false));
  46
  47 static cl::opt<bool>
  48 DumpAsm("d", cl::desc("Print assembly as parsed"), cl::Hidden);
  49
  50 static cl::opt<bool>
  51 DisableVerify("disable-verify", cl::Hidden,
  52               cl::desc("Do not run verifier on input LLVM (dangerous!)"));
  53
  54 int main(int argc, char **argv) {
  55   // Print a stack trace if we signal out.
  56   sys::PrintStackTraceOnErrorSignal();
  57   PrettyStackTraceProgram X(argc, argv);
  58   llvm_shutdown_obj Y;  // Call llvm_shutdown() on exit.
  59   cl::ParseCommandLineOptions(argc, argv, "llvm .ll -> .bc assembler\n");
  60
  61   int exitCode = 0;
  62   std::ostream *Out = 0;
  63   try {
  64     // Parse the file now...
  65     ParseError Err;
  66     std::auto_ptr<Module> M(ParseAssemblyFile(InputFilename, Err));
  67     if (M.get() == 0) {
  68       Err.PrintError(argv[0], errs());
  69       return 1;
  70     }
  71
  72     if (!DisableVerify) {
  73       std::string Err;
  74       if (verifyModule(*M.get(), ReturnStatusAction, &Err)) {
  75         cerr << argv[0]
  76              << ": assembly parsed, but does not verify as correct!\n";
  77         cerr << Err;
  78         return 1;
  79       }
  80     }
  81
  82     if (DumpAsm) cerr << "Here's the assembly:\n" << *M.get();
  83
  84     if (OutputFilename != "") {   // Specified an output filename?
  85       if (OutputFilename != "-") {  // Not stdout?
  86         if (!Force && std::ifstream(OutputFilename.c_str())) {
  87           // If force is not specified, make sure not to overwrite a file!
  88           cerr << argv[0] << ": error opening '" << OutputFilename
  89                << "': file exists!\n"
  90                << "Use -f command line argument to force output\n";
  91           return 1;
  92         }
  93         Out = new std::ofstream(OutputFilename.c_str(), std::ios::out |
  94                                 std::ios::trunc | std::ios::binary);
  95       } else {                      // Specified stdout
  96         // FIXME: cout is not binary!
  97         Out = &std::cout;
  98       }
  99     } else {
 100       if (InputFilename == "-") {
 101         OutputFilename = "-";
 102         Out = &std::cout;
 103       } else {
 104         std::string IFN = InputFilename;
 105         int Len = IFN.length();
 106         if (IFN[Len-3] == '.' && IFN[Len-2] == 'l' && IFN[Len-1] == 'l') {
 107           // Source ends in .ll
 108           OutputFilename = std::string(IFN.begin(), IFN.end()-3);
 109         } else {
 110           OutputFilename = IFN;   // Append a .bc to it
 111         }
 112         OutputFilename += ".bc";
 113
 114         if (!Force && std::ifstream(OutputFilename.c_str())) {
 115           // If force is not specified, make sure not to overwrite a file!
 116           cerr << argv[0] << ": error opening '" << OutputFilename
 117                << "': file exists!\n"
 118                << "Use -f command line argument to force output\n";
 119           return 1;
 120         }
 121
 122         Out = new std::ofstream(OutputFilename.c_str(), std::ios::out |
 123                                 std::ios::trunc | std::ios::binary);
 124         // Make sure that the Out file gets unlinked from the disk if we get a
 125         // SIGINT
 126         sys::RemoveFileOnSignal(sys::Path(OutputFilename));
 127       }
 128     }
 129
 130     if (!Out->good()) {
 131       cerr << argv[0] << ": error opening " << OutputFilename << "!\n";
 132       return 1;
 133     }
 134
 135     if (!DisableOutput)
 136       if (Force || !CheckBitcodeOutputToConsole(Out,true))
 137         WriteBitcodeToFile(M.get(), *Out);
 138   } catch (const std::string& msg) {
 139     cerr << argv[0] << ": " << msg << "\n";
 140     exitCode = 1;
 141   } catch (...) {
 142     cerr << argv[0] << ": Unexpected unknown exception occurred.\n";
 143     exitCode = 1;
 144   }
 145
 146   if (Out != &std::cout) delete Out;
 147   return exitCode;
 148 }
 149